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Evaluation Of An Education Intervention For The Staff On The Head Of The Bed Elevation In The Pediatric Intensive Care UnitJohnson, Randall 01 January 2007 (has links)
Elevating the head of bed (HOB) reduces risks for aspiration and ventilator associated pneumonia (VAP) in the adult population. Educational interventions have resulted in improvements in achieving a target HOB elevation of 30° in adults. Limited research has addressed this intervention in the pediatric intensive care unit (PICU). The aim of this study was to determine if an educational intervention for the PICU staff would result in improvement in the HOB elevation in the PICU. Four research questions were studied: 1) What is the common practice related to the elevation of the HOB in the PICU? 2) Is there a difference in the mean HOB elevation before and after an education intervention? 3) Is there a difference in the percent of time the HOB is at or above 30° after the intervention? and 4) What factors influence HOB elevation in the PICU? A quasi-experimental, pre, and post measurement, with nonequivalent comparison group design was used. The angle of the HOB elevation was measured with the “Pitch and Angle Locator” (PAL) (Johnson, Mequon, WI). Baseline measurements (n = 99) were obtained for patients admitted to a PICU at various days and times over a 2-week period. An educational intervention was done for the staff members in the PICU, with a focus on the importance of keeping the HOB up and strategies for measuring the HOB elevation. Posters to reinforce the information were placed on the unit. Post-intervention, measurements (n = 98) were obtained for another 2-week period. At the time of data collection, staff members caring for the PICU patients were asked to provide responses for what influenced them to place the patient at the documented HOB elevation. Children were older in the post-intervention group than in the pre-intervention (8.8 yrs, vs. 3.7, yrs, respectively, t = -6.67, df = 195, p= .000). The children also weighed more in the post-intervention group than in the pre-intervention (32.0 kg vs. 19.7 kg, respectively, t = -4.19, df= 195, p = .000). The mean HOB elevation was 23.5° before the intervention. After the intervention, the mean HOB increased to 26.5° (t = -1.19, df 195, p = .033). For ventilated patients, the mean HOB elevation went from 23.6° to 29.1° (t = -3.25, df 95, p= .001), and for patients mechanically ventilated and in an adult bed, the mean increased from 26° ± 7.89°, pre- intervention to 30° ± 8.59° postintervention (t = -1.80, df 63, p = .038). The percent of the time the measures were greater than 30° increased from 26% to 44% pre- and post-intervention respectively (χ2 6.71, df 1, p= .005). Responses (n = 230) related to the factors that influenced positioning were categorized as follows: physician order (3%), safety (7%), found this way (11%), therapeutic intervention (16%), comfort (24%), and patient condition (39%). An educational intervention can impact the practice of elevation of the HOB in a PICU, thus decreasing the risks of developing aspiration and VAP. Although the mean HOB increased statistically, the HOB was less than 30° in more than half of the post intervention measurements, indicating the need for ongoing reinforcement of the education. The PAL device was a new, reliable method for recording HOB elevation in both adult beds and cribs. Follow-up research is needed to determine if these gains in HOB elevation have been sustained over time and their impact on VAP.
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Dynamics and functions of protective lung B cells after pneumococcal infectionEtesami, Neelou Shirin 12 February 2024 (has links)
As lower respiratory infections are a leading cause of morbidity and mortality worldwide, and have been linked to periodic pandemics, there is a heightened interest in understanding how protective immune cells are mobilized in response to pathogens and contribute to local tissue resistance. The existence of non-recirculating lung resident memory B (BRM) cells was recently defined in an influenza virus infection model and inferred to be protective. Our body of knowledge has since grown significantly, but many unknowns including BRM cell establishment dynamics and requirements for maintenance remain.
We previously used a murine model of serotype-independent immunity against Streptococcus pneumoniae (Sp) to show that resident memory B (BRM) cells are seeded extravascularly in the lung after local bacterial exposures independently of mature tertiary lymphoid structure formation. Using a transgenic mouse model which allowed for the depletion of PD-L2+ memory B cells, we demonstrated that lung PD-L2+ BRM cells directly contribute to clearance of a heterotypic Sp challenge infection, and that their absence correlated with diminished local antibody secreting cell (ASC) activities. Our findings provide evidence of serotype-independent protection mediated by the PD-L2+ BRM cell population and suggest that this is due to their capacity to rapidly differentiate into local ASCs upon memory recall.
We carried out additional studies to elucidate lung B cell population dynamics, locations, and T-dependent requirements for establishment and maintenance after Sp infections. Singular exposure to self-limiting pneumococcal infection was insufficient to generate lasting BRM cells, as well as other heterogeneous extravascular B cell populations which were tracked over time. This included a transient population of proliferatively active lung GC B cells whose accumulation in the lung corresponded with the temporary appearance of organized lymphoid tissue. After an initial respiratory infection was administered to allow for immune priming in the lung and in draining lymph nodes, disruption of T cell interactions during a 2nd infection prevented pan extravascular B cell accumulation and abrogated lung BRM cells.
We posit that our findings are relevant for the development of improved serotype-independent preventative strategies against pneumococcal pneumonia, and all respiratory pathogens in general. Advancing our understanding of tissue-resident B cell populations will aid in the development of next generation vaccines that leverage mucosal memory against respiratory pathogens. / 2025-02-12T00:00:00Z
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Chlorhexidine in the prevention of ventilator associated pneumonia : a systematic reviewSnyders, Olivia Gayle 12 1900 (has links)
Thesis (MCur)--Stellenbosch University, 2011. / ENGLISH ABSTRACT: Ventilator-Associated Pneumonia (VAP) is a hospital acquired infection, not present or
incubating at the time of admission and developing in patients during the process of care within
the hospital setting. Between nine and twenty-seven percent of patients who are mechanically
ventilated will develop ventilator-associated pneumonia. Mortality rates for ventilated patients
who develop ventilator-associated pneumonia are estimated to be between 33-50%. The Institute
for Healthcare Improvements (IHI) in 2006 recommended the use of ‘care bundles’ to reduce
VAP but no statistically significant decline has been noted.
Despite the completion of an extensive literature search for purposes of this review, no statistical
data on nosocomial infections or nosocomial pneumonia relevant to South Africa was found.
Mechanical ventilation, a support therapy used in approximately one third of patients,
significantly increases the patient’s risk of developing this nosocomial pneumonia. Critically ill
patients are by virtue of their critical illness more prone to the development of infections,
especially ventilator-associated pneumonia. Consistent evidence suggests that oropharyngeal
colonization can be associated with the development of VAP. Studies focusing on standard oral
care, with or without the concurrent use of chlorhexidine, have not provided sufficient evidence
for the use of chlorhexidine in VAP prevention. Chlorhexidine is an antiseptic agent, which
when tested, proved to reduce total respiratory tract infections by up to 69% (DeRiso et al,
1996:1558).
Objective: The aim of this study was to systematically appraise and review evidence on the
effectiveness of chlorhexidine in reducing the incidence of ventilator-associated pneumonia in
adult patients. The secondary aim was to systematically summarize evidence on the use of
chlorhexidine in reducing mortality.
Methodology: An extensive literature search of studies published in English was undertaken.
Electronic databases searched were CENTRAL, CINAHL, EMBASE and MEDLINE. Reference
lists of articles, textbooks and conference summaries were examined. Literature searches were conducted using Medical Subject Headings (MeSH). These included: Ventilator-associated
pneumonia, chlorhexidine, VAP and oral care. Eight randomized controlled trials, investigating
the efficacy of Chlorhexidine in ventilator-associated pneumonia prevention in adults met the
inclusion criteria. The effect measure of choice was Risk ratio with 95% confidence intervals for
dichotomous data using the random effects (Mantel-Haenszel) model; (p=value of 0.05).
Heterogeneity was assessed using the Cochrane Q statistic and I².
Results: Eight randomized controlled trials met the inclusion criteria for this review. Pooled risk
ratio for the incidence of ventilator-associated pneumonia was 0.64 (95% CI; 0.44-0.91; p
=0.18). Treatment with chlorhexidine decreased the risk of ventilator-associated pneumonia by
36%. There was no evidence of Chlorhexidine reducing mortality.
Conclusions: Chlorhexidine is a cost effective safe treatment in the prevention of VAP. The use
of 2% chlorhexidine may be more effective in reducing the incidence of VAP. No studies were
found conducted in developing countries. More rigorously designed trials using 2%
chlorhexidine are recommended. / AFRIKAANSE OPSOMMING: Agtergrond
Ventilator-Geassosieerde Longontsteking (VAP) is 'n hospitaal verkry infeksie, nie teenwoordig
met toelating nie. Ventilator-geassosieerde longontsteking word ontwikkel in pasiënte tydens die
proses van sorg in die hospitaal. Tussen nege en sewe en twintig persent van pasiënte wat
meganies geventileer word kry ventilator-geassosieerde pneumonie. Sterftesyfers vir
geventileerde pasiënte wat ventilator-geassosieerde pneumonie ontwikkel is na raming tussen 33-
50%. Die Institute for Healthcare Improvements (IHI) het in 2006 die gebruik van 'sorg bundels'
aanbeveel om VAP te verminder, maar geen statisties beduidende daling is aangeteken nie.
Ten spyte van 'n uitgebreide literatuur soek, is geen statistiese data op nosokomiale infeksies of
nosokomiale longontsteking toepaslik tot Suid-Afrika gevind nie. Meganiese ventilasie, 'n
ondersteuningsterapie wat gebruik word in ongeveer een derde van die pasiënte, verhoog
aansienlik die pasiënt se risiko vir die ontwikkeling van hierdie nosokomiale longontsteking.
Kritiek siek pasiënte is op gronde van hul kritieke toestand meer geneig tot die ontwikkeling van
infeksies, veral ventilator-geassosieerde pneumonie. Konsekwente bewyse dui daarop dat
orofaringeale kolonisasie kan met die ontwikkeling van VAP geassosieer word. Studies wat
fokus op standaard mond sorg, met of sonder die gelyktydige gebruik van chlorhexidine, het nie
voldoende bewyse vir die gebruik van chlorhexidine in VAP voorkoming nie. Chlorhexidine is 'n
antiseptiese agent, wat wanneer in een verewekansigde gekontroleerde studies (VGS) getoets
was die totale respiratoriese kanaal infeksies verminder deur tot 69%.
Doel: Die doel van hierdie sistematiese literatuuroorsig was om stelselmatig te evalueer en
bewyse oor die effektiwiteit van chlorhexidine in die vermindering en voorkoms van ventilatorgeassosieerde
pneumonie in volwasse pasiënte te hersien. Die sekondêre doel was om
stelselmatig bewyse op te som op die gebruik van chlorhexidine in die vermindering van sterfte.
Metodiek: 'n Uitgebreide literatuursoektog van studies wat in Engels gepubliseer is was
onderneem. CENTRAL, CINAHL, EMBASE en MEDLINE was deursoek. Naslaanlyste van
artikels, handboeke en konferensie opsommings is ondersoek. Die literatuur soektog is uitgevoer
met behulp van Medical Subject Headings (MeSH). Dit sluit in: ventilator-geassosieerde pneumonie, chlorhexidine, VAP en mond sorg. Agt verewekansigde gekontroleerde studies
(VGS), wat die doeltreffendheid van Chlorhexidine in ventilator-geassosieerde pneumonie
voorkoming in volwassenes ondersoek, was ingesluit vir hierdie studie. Die effek mate van keuse
was risiko ratio (RR) met 95% vertrouensintervalle met behulp van die ewekansige effekte
(Mantel-Haenszel) model; (p = 0.05). Heterogeniteit is bepaal deur gebruik te maak van die
Cochrane Q- statistiek en I².
Hoof resultate: Agt verewekansigde gekontroleerde studies (VGS) het die insluiting kriteria vir
hierdie oorsig gepas. Gepoelde risiko ratio vir die voorkoms van ventilator-geassosieerde
pneumonie: Risiko Ratio (RR) was 0.64 (95% CI; 0.44-0.91; p=0.18).
Gevolgtrekkings: Behandeling met chlorhexidine het die risiko van ventilator-geassosieerde
pneumonie met 36% gedaal. Daar was geen bewyse van Chlorhexidine op die vermindering van
mortaliteit nie. Chlorhexidine is 'n koste-effektiewe veilige behandeling in die voorkoming van
VAP. Die gebruik van 2% chlorhexidine kan moontlik meer effektief wees in die vermindering
van die voorkoms van VAP. Meer streng ontwerp studies met 2% chlorhexidine word aanbeveel.
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Improving the quality of care for inpatient management of childhood pneumonia at the first level referral hospital : a country wide programmeEnarson, Penelope Marjorie 04 1900 (has links)
Thesis (MCur)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: Pneumonia is the greatest single cause of mortality in children less than five years of age throughout the world causing more deaths than those due to AIDS, malaria and tuberculosis combined. Approximately 50% of all childhood pneumonia deaths occur in sub-Saharan Africa. Children in developing countries being treated for pneumonia frequently have one or more comorbid conditions which increases their risk of dying. The proper management of the child with severe or very severe pneumonia is essential to reduce case fatality. Standard case management (SCM) of pneumonia, has been shown to be an effective intervention to reduce deaths from pneumonia, but what is lacking is a means of delivering it in low-resource/high burden countries.
A major barrier to wide application of this intervention in low-income countries is weak health-care systems with insufficient human and financial resources for implementing SCM to a sufficient number of children at a level of quality and coverage that would result in a significant impact. The objective of this dissertation is to address this issue by investigating ways of improving delivery of standard case management of pneumonia in district hospitals throughout Malawi, a high HIV-prevalent country which would result in a decrease in the in-hospital case fatality rates (CFR) from pneumonia in children less than five years of age.
We reviewed the evidence base for SCM. Then we evaluated the development and implementation of a national Child Lung Health Programme (CLHP) to deliver SCM of severe and very severe pneumonia and a programme to provide uninterrupted oxygen supply in all paediatric wards at District Hospitals throughout Malawi. We demonstrated that it was feasible to implement and maintain both programmes country-wide.
Thirdly we evaluated the trend in case fatality rates in infants and young children (0 to 59 months of age) hospitalized and treated for severe and very severe pneumonia over the course of the implementation of the CLHP. The findings from this study showed that in the majority (64%) of cases, who were aged 2-59 months with severe pneumonia there was a significant effect of the intervention that was sustained over time whereas in the same age group children treated for very severe pneumonia there was no interventional benefit. No benefit was observed for neonates.
Fourthly we investigated factors associated with poor outcome reported in the previous study, in a subset of this cohort to determine the individual factors including demographics of the study population, recognised co-morbidities and clinical management that were associated with inpatient death. This study identified a number of factors associated with poor pneumonia-related outcomes in young infants and children with very severe pneumonia. They included co-morbidities of malaria, malnutrition, severe anaemia and HIV infection. The study found that the majority of reported comorbid conditions were based on clinical signs alone indicating a need for more accurate diagnosis and improved management of these comorbidities that may lead to improved outcomes. Other identified factors included a number of potentially modifiable aspects of care where adjustments to the implementation of SCM are indicated. These included enhancing correct classification of the severity of the disease, the use of correct antibiotics according to standard case management, more extensive availability and use of oxygen together with oximetry to guide its use,.
Finally recommendations were made to address the identified reasons for poor outcomes and suggested future research. / AFRIKAANSE OPSOMMING: Pneumonie is die grootste enkele oorsaak van sterftes by kinders jonger as 5 jaar in die wêreld en veroorsaak meer kindersterftes as die menslike immuungebrekvirus (MIV), malaria en tuberkulose saam. Ongeveer 50% van kindersteftes van pneumonie kom in sub-Sahara-Afrika voor. Kinders in ontwikkilende lande, wie vir pneumonie behandel word, het dikwels een of meer bydraende toestande wat die doodsrisiko verhoog. Kinders wie ernstige of baie ernstige pneumonie onderlede het moet korrek behandel word om sterfte te voorkom. Die standaard protokolle om kinderpneumonie korrek te behandel het getoon om effektief te wees om die sterftesyfers te verlaag. In lae inkomste lande bestaan die strategieë nie om die protokolle aan te wend nie.
‘n Groot struikelblok in die aanwending van die pneumonie behandelingsprotokolle in lae-inkomste lande is die swak gesondheidsorgsisteme met onvoldoende menslike en finansiële hulpbronne. Die tekorte gee aanleiding tot die beperkte implementering van pneumonie protokolle wat die omvang en kwaliteit van die pneumonie protokolle beperk en daarom impakteer die protokolle nie op die kindersterftesyfer nie. Die doel van die verhandeling is om hierdie probleem aan te spreek deur navorsing hoe om die pneumonie protokolle landwyd in alle distrikhospitale in Malawi, ‘n land met ‘n hoë MIV prevalensie, aan te wend om sodoende die kindersterftesyfer (kinders jonger as 5 jaar) as gevolg van pneumonie te verlaag.
Ons het die getuienis van die pneumonie protokolle ondersoek. Hierna is ‘n nasionale Kinderlong Gesondheidsprogram ontwikkel en landwyd geïmplementeer. Volgens die program is kinders met ernstige en baie ernstige pneumonie volgens Wêreldgesondheidsorganisasie (WGO) protokolle behandel. Ononderbroke suurstoftoevoer in alle pediatriesesale in distrikshospitale in Malawi veskaf. Die navorsing het getoon dat die implementering en instandhouding van pneumonie behandelingsprotokolle is landwyd moontlik.
Verder het ons die tendens ondersoek of die kindersterftesyfer in babas en jong kinders (0 tot 59 maande) wat in die hospital opgeneem en behandel is vir ernstige en baie ernstige pneumonie tydens die implementering van pneumonie protokolle verminder het. Die bevindinge van hierdie verhandeling wys dat in die meerderheid (64%) van die kinders tussen 2 en 59 maande met ernstige pneumonie, en met die toepassing van die pneumonie protokolle, statistiesbetekenvol die sterfte syfer verlaag het. Die protokolle vir die behandeling van baie erstige pneumonie het nie dieselfde wenslike effek gehad nie. In neonate (jonger as 2 maande) was daar ook geen verlaging in die sterftesyfer nie. Laastens het ons die redes vir die swak uitkomste ondersoek in ‘n substudie en veral klem gelê op bydraende siektes en kliniesesorg tekorte geassosieer met pneumonie sterftes. Die studie het ‘n aantal faktore geïdentifiseer wat bygedra het tot die sterftesyfer in kinders met baie ernstige pneumonie en in neonate. Die geïdentifiseerde bydraende faktore het malaria, wanvoeding, erge anemie en MIV-infeksie ingesluit. Voorkomende maatreëls moet vir die geïdentifiseerde faktore ingestel word. Aanpassings in die pneumonie protokolle is voorgestel.
Ten slotte word aanbevelings gemaak om die geïdentifiseerde redes vir swak uitkomste aan te spreek en verdere navorsingidees word aanbeveel.
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Avaliação da presença de microrganismos periodontopatogênicos em amostras subglóticas de pacientes intubados e mecanicamente ventilados, submetidos a cirurgias eletivas / Evaluation of the presence of periodontopathogenic microorganisms in subglottic samples of intubated and mechanically ventilated patients submitted to elective surgeriesMorillo, Carlos Manuel Rubio 25 February 2019 (has links)
A pneumonia associada à ventilação mecânica (PAVM) é uma condição inflamatória infecciosa cuja etiopatogenia ainda está mal definida. Embora a principal via de infecção do trato respiratório inferior permaneça desconhecida, a colonização do trato orofaríngeo é geralmente considerada como a principal via de infecção para PAVM. Desta forma, o objetivo deste estudo foi avaliar a presença de microrganismos periodontopatogênicos em amostras subglóticas de pacientes intubados e mecanicamente ventilados, submetidos a cirurgias eletivas. Adicionalmente, este estudo avaliou o impacto do estado de saúde periodontal e da descontaminação bucal com clorexidina (CHX) na quantificação destes microrganismos. Foram incluídos 43 pacientes programados para cirurgia eletiva sob anestesia geral com intubação orotraqueal. Um exame periodontal de boca toda foi realizado anteriormente a cirurgia. A periodontite foi definida como: i) dois ou mais sítios interproximais com nível clínico de inserção (NIC) >=4 mm ou dois ou mais sítios interproximais com profundidade clínica de sondagem (PCS) >= 5 mm (Definição 1); ii) NCI >= 4 mm ou PCS >= 5 mm em pelo menos seis sítios interproximais (Definição 2); e iii) NCI >= 4 mm ou PCS >= 5 mm em pelo menos dois sítios interproximais em cada quadrante (Definição 3). No dia da cirurgia, os pacientes foram randomizados em dois grupos que fizeram um enxague intraoral com 15 ml de CHX 0,12% (teste) ou solução salina (controle) por 30 segundos. Após 3h de intubação orotraqueal, o conteúdo da região subglótica foi aspirado e armazenado a -80ºC. A quantificação de Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans), Porphyromonas gingivalis (P. gingivalis) e Tannerella forsythia (T. forsythia) foi feita pela reação em cadeia da polimerase quantitativa em tempo real. As contagens de P. gingivalis, T. forsythia e A. actinomycetemcomitans não diferiram entre pacientes periodontalmente saudáveis e aqueles diagnosticados com periodontite, independentemente da definição de periodontite (p> 0,05). De forma análoga, nenhum dos parâmetros periodontais avaliados tiveram impacto nas contagens subglóticas de P. gingivalis, T. forsythia e A. actinomycetemcomitans (p> 0,05). Por fim, o grupo que recebeu um enxague intraoral único pré-intubação com CHX 0,12% apresentou níveis reduzidos de P. gingivalis e A. actinomycetemcomitans em amostras do conteúdo subglótico. Em resumo, este estudo demonstrou presença de microrganismos periodontopatogênicos na região subglótica de pacientes intubados e mecanicamente ventilados. Enquanto a descontaminação intraoral em dose única com CHX foi associada com níveis reduzidos de A. actinomycetemcomitans e P. gingivalis, o estado de saúde periodontal não interferiu nos níveis de A. actinomycetemcomitans, P. gingivalis e T. forsythia na região subglótica. / Ventilator-associated pneumonia (VAP) is an infectious inflammatory condition whose etiopathogenesis is still poorly defined. Although the main route of infection to the lower respiratory tract remains unknown, colonization of the oropharyngeal tract is generally considered the main route of infection for VAP. Thus, the objective of this study was to evaluate the presence of periodontopathogenic microorganisms in subglottic samples of intubated and mechanically ventilated patients submitted to elective surgeries. Furthermore, this study evaluated the impact of periodontal health status and oral decontamination with chlorhexidine (CHX) on the quantification of these microorganisms. 43 patients scheduled for elective surgery under general anesthesia with orotracheal intubation were included. Full-mouth periodontal examination was performed prior to surgery. Periodontitis was defined as: i) two or more interproximal sites with clinical attachment level (CAL) >=4 mm or two or more interproximal sites with clinical probing depth (CPD) >= 5 mm (Definition 1); ii) CAL >= 4 mm or CPD >= 5 mm in at least six interproximal sites (Definition 2); and iii) CAL >= 4 mm or CPD >= 5 mm in at least two interproximal sites in each quadrant (Definition 3). On the day of surgery, patients were randomized into two groups that rinsed preoperatively with 15 ml CHX 0.12% (test) or saline (control) for 30 seconds. After 3h of orotracheal intubation, the contents of the subglottic region were aspirated and stored at -80°C. Quantification of Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans), Porphyromonas gingivalis (P. gingivalis) and Tannerella forsythia (T. forsythia) was done by quantitative real-time polymerase chain reaction. P. gingivalis, T. forsythia, and A. actinomycetemcomitans counts did not differ between periodontally healthy patients and those diagnosed with periodontitis, regardless of the definition of periodontitis (p> 0.05). Similarly, none of the periodontal parameters evaluated had an impact on the subglottic counts of P. gingivalis, T. forsythia and A. actinomycetemcomitans (p> 0.05). Finally, the group receiving a single pre-intubation intraoral rinse with CHX 0.12% presented reduced levels of P. gingivalis and A. actinomycetemcomitans in samples of the subglottic content. In summary, this study demonstrated the presence of periodontopathogenic microorganisms in the subglottic region of intubated and mechanically ventilated patients. While a single dose intraoral decontamination with CHX was associated with reduced levels of A. actinomycetemcomitans and P. gingivalis, the periodontal health status did not affect the levels of A. actinomycetemcomitans, P. gingivalis and T. forsythia in the subglottic region.
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Pneumonia no acidente vascular cerebral: frequência, preditores e desfechos associados / Pneumonia in stroke: frequency, predictors and associated outcomesMiranda, Rúbia Poliana Crisóstomo 11 June 2018 (has links)
Introdução: Pneumonia é uma das complicações mais frequentes após Acidente Vascular Cerebral (AVC), com incidência variando de 2,3% a 47,3%. Nesse estudo, nosso objetivo foi identificar a frequência e os fatores associados com pneumonia após AVC e avaliar o impacto da pneumonia quanto ao óbito intra-hospitalar e quanto aos desfechos dependência funcional e óbito em três meses após o AVC. Métodos: Participaram do estudo pacientes que preencheram os critérios de inclusão (Idade maior que 18 anos de ambos os sexos e diagnóstico médico de AVC isquêmico ou hemorrágico agudo, confirmado por exames de neuroimagem) e nenhum dos critérios de exclusão (Ataque Isquêmico Transitório, Hemorragia Subaracnóidea, Trombose Venosa Cerebral, outros quadros clínicos em que não foi confirmado diagnóstico de AVC, ictus antigo, AVC hemorrágico de causa secundária por malformação arteriovenosa, aneurisma cerebral, neoplasia craniana, distúrbios da coagulação, entre outros; não concordância em participar do estudo ou não assinatura do Termo de Consentimento Livre e Esclarecido). Estes pacientes foram admitidos na Unidade de Emergência do Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo (HCFMRP-USP) e incluídos no Registro de Acidente Vascular Encefálico (REAVER) no período de abril de 2015 a setembro de 2016. Os dados demográficos e clínicos foram coletados de forma prospectiva pelos coordenadores de pesquisa do REAVER. Quando possível, os pacientes foram submetidos à avaliação clínica da deglutição por três fonoaudiólogas. Os prontuários de todos os pacientes foram revisados por um infectologista para confirmar o diagnóstico de pneumonia. Resultados: Foram estudados 478 pacientes com AVC agudo. Considerando a amostra total do estudo, encontramos uma frequência relativa de 24% de pneumonia, 11,5% de óbito intra-hospitalar e 36,8% de dependência funcional ou óbito após três meses do AVC. Dos pacientes com pneumonia, 32,2% foram a óbito intra-hospitalar e 84,3% apresentaram dependência funcional ou óbito após três meses do ictus.Na análise multivariada por regressão logística para preditores de pneumonia após AVC, a gravidade do AVC (p=0,001), AVC hemorrágico (p=0,012) e disfagia (p=0,001) foram preditores independentes para pneumonia. Conclusão: Nosso estudo confirma que a pneumonia é uma complicação frequente após o AVC, sendo associada com gravidade do AVC, AVC hemorrágico e disfagia. Os pacientes com pneumonia apresentaram alta frequência de óbito intra-hospitalar e alta dependência funcional ou óbito após três meses do AVC. / Introduction: Pneumonia is one of the most frequent complications after stroke, with an incidence varying from 2.3% to 47.3%. In this study, our goal was to identify the frequency and factors associated with post-stroke pneumonia and to assess the impact of pneumonia on in-hospital death, functional dependence outcomes and death at three months after stroke. Methods: Were included in the study, patients who met the criteria for participation (over 18 years old for both sexes and medical diagnosis of acute hemorrhagic or ischemic stroke, confirmed by neuroimaging exams) and none of the exclusion criteria (Transient Ischemic Attack, Subarachnoid Hemorrhage, Cerebral Venous Thrombosis, clinical conditions in which a diagnosis of stroke was not confirmed, not acute stroke, hemorrhagic stroke due to arteriovenous malformation, brain aneurysm, brain tumor, coagulation disorders, other diagnosis; non-agreement to participate in the study or non-signing of the Informed Consent Form). These patients were admitted to the University Hospital Emergency Unit of the Medical School of Ribeirão Preto (HCFMRP-USP) and included in the Registry of Stroke (REAVER) from April 2015 to September 2016. Demographic and clinical data were collected prospectively by the REAVER research coordinators. The patients underwent clinical evaluation of swallowing by three speech therapists whenever possible. The medical records of all patients were reviewed by an infectious disease specialist to confirm the diagnosis of pneumonia. Results: A total of 478 patients with acute stroke were included. Considering the total sample of the study, we found a relative frequency of 24% of pneumonia, 11.5% of in-hospital death and 36.8% of functional dependence or death after three months of stroke. Regarding the patients with pneumonia, 32.2% died in the hospital and 84.3% had functional dependence or death after three months of stroke. In the multivariate logistic regression analysis for predictors of poststroke pneumonia, the severity of stroke (p = 0.001), hemorrhagic stroke (p = 0.012), and dysphagia (p = 0.001) were independent predictors for pneumonia. Conclusion: Our study confirms that pneumonia is a common complication afterstroke and is associated with severity of stroke, hemorrhagic stroke and dysphagia. Patients with pneumonia had a higher frequency of in-hospital death and greater functional dependence or death after three months of stroke.
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Imunização pulmonar com nanopartículas contendo o antígeno PspA (Pneumococcal surface protein A) / PULMONARY IMMUNIZATION WITH NANOPARTICLES CONTAINING THE ANTIGEN PspA (PNEUMOCOCCAL SURFACE PROTEIN A)Rodrigues, Tasson da Costa 09 April 2018 (has links)
Streptococcus pneumoniae, ou pneumococo, é um constituinte da microbiota humana, mas em alguns casos pode causar doenças, como pneumonia, bacteremia e meningite. Uma das principais formas de conter as infecções pneumocócicas foi o desenvolvimento de vacinas baseadas na indução de anticorpos contra o polissacarídeo capsular (PS). Como as vacinas pneumocócicas conjugadas (PCVs) possuem um número limitado de PSs e sua efetividade contra doenças não-invasivas ainda é controversa, o desenvolvimento de uma nova geração de vacinas que não sejam sorotipo-específicas continua sendo uma prioridade. Pneumococcal surface protein A (PspA) é um antígeno com grande potencial para uso em vacinas contra pneumococo. PspA apresenta certa variabilidade entre isolados e é dividida em família 1 (clados 1 e 2), família 2 (clados 3, 4 e 5) e família 3 (clado 6). O objetivo deste trabalho é avaliar a imunogenicidade e eficácia de nanopartículas (NPs) compostas do polímero poli(glicerol-adipato-co-ω-pentadecalactona) (PGA-co-PDL) contendo o antígeno PspA (PspA4Pro) e formuladas em partículas micrométricas (NP/NCMP PspA4Pro) em modelo murino de imunização pulmonar. Inicialmente, foram testadas três técnicas de inoculação para imunização pulmonar de camundongos. Tanto a utilização de um insuflador pulmonar para inoculação das NP/NCMPs sob a forma de pó quanto o uso de um microsprayer para inoculação das NP/NCMPs após ressuspensão em salina não foram capazes de induzir uma resposta de indução de IgG sérico de forma homogênea. Na terceira estratégia de imunização foi utilizada uma micropipeta para a imunização através de instilação por via nasal de duas doses da ressuspensão das NP/NCMPs. A imunização com NP/NCMP PspA4Pro através dessa técnica mostrou-se adequada, com a indução de IgG anti-PspA4 Pro no soro e no lavado broncoalveolar (BALF). Anticorpos IgG induzidos pela imunização com NP/NCMP PspA4Pro mostraram ligação à superfície de bactérias intactas expressando PspA dos clados 3, 4 e 5 (família 2), mas não foi observada ligação a bactérias expressando PspA dos clados 1 e 2 (família 1). Camundongos imunizados foram então desafiados com as linhagens ATCC6303 (sorotipo 3, PspA de clado 5) ou EF3030 (sorotipo 19F, PspA de clado 1) e o BALF foi coletado após 12 e 24 horas, respectivamente. Foi observada uma redução da carga bacteriana no BALF após desafio com a linhagem ATCC6303, além de uma redução na concentração de IL-6, TNF- KC/CXCL1 e MIP-2/CXCL2 em camundongos imunizados com NP/NCMP PspA4Pro. Todavia, esta redução da carga bacteriana no BALF não foi observada após desafio com a linhagem EF3030. Foi realizado ainda um desafio para avaliar a sobrevivência final após desafio com a linhagem ATCC6303 e foi observado que a imunização com NP/NCMP PspA4Pro foi capaz de induzir proteção parcial. A imunização pulmonar NP/NCMP PspA4Pro foi, portanto, capaz de induzir anticorpos no soro e pulmões dos camundongos, conferindo proteção contra uma linhagem de pneumococo expressando PspA da mesma família. Deste modo, estudos futuros são necessários para garantir maior proteção vacinal. / Streptococcus pneumoniae, or pneumococcus, is part of the human microbiota, but in some cases it can cause diseases, such as pneumonia, bacteremia and meningitis. One of the main forms of controlling pneumococcal infections was the development of vaccines based on the induction of antibodies against capsular polysaccharide (PS). Since a limited number of serotypes are included in pneumococcal conjugate vaccines (PCVs) and their effectiveness against non-invasive diseases is still controversial, the development of a new generation of serotype-independent vaccines is still a priority. Pneumococcal surface protein A (PspA) is an antigen with great potential for vaccine use. PspA shows some variability between strains and is divided in family 1 (clades 1 and 2), family 2 (clades 3, 4 and 5) and family 3 (clade 6). The aim of this work is to evaluate the immunogenicity and efficacy of poly (glycerol-adipate-co-&omega-pentadecalactone) (PGA-co-PDL) nanoparticles (NPs) containing PspA (PspA4Pro) and formulated in micrometric particles (NP/NCMP PspA4Pro) in a murine model of pulmonary immunization. Initially, three inoculation techniques were tested for lung immunization of mice. Both the inoculation of the NP/NCMPs as dry powder using a pulmonary insufflator and inoculation of the resuspension of the NP/NCMPs in saline using a microsprayer did not induce IgG serum antibodies reproducibly. For the third immunization strategy, a micropipette was used for immunization through nasal instillation of two doses of the resuspension of the NP/NCMPs. Immunization with NP/NCMP PspA4Pro using this technique showed reproducible results, with the induction of anti-PspA4Pro IgG in serum and bronchoalveolar lavage (BALF). IgG antibodies induced by immunization with NP/NCMP PspA4Pro showed binding to the surface of intact bacteria expressing PspA from clades 3, 4 and 5 (family 2), but no binding was observed for bacteria expressing PspA from clades 1 and 2 (family 1). Immunized mice were then challenged with strains ATCC6303 (serotype 3, PspA clade 5) or EF3030 (serotype 19F, PspA1) and BALF was collected after 12 and 24 hours, respectively. A reduction in bacterial load in BALF was observed in mice challenged with ATCC6303. A reduction in IL-6, TNF-KC/CXCL1 and MIP-2 CXCL2 levels in BALF of mice immunized with NP/NCMP PspA4Pro was also observed. Reduction in bacterial load was not observed for mice challenged with strain EF3030 though. A challenge with strain ATCC6303 strain was also performed to evaluate overall survival and partial protection was observed for the group immunized with NP/NCMP PspA4Pro. In conclusion, lung immunization with NP/NCMP PspA4Pro is able to induce antibodies in serum and lungs, conferring protection against a pneumococcal strain expressing PspA from the same family. Future studies are thus necessary to guarantee broader vaccine protection.
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Avaliação das prostaglandinas e leucotrienos na infecção pulmonar induzida por Achromobacter xylosoxidans / Evaluation of prostaglandin and leukotrienes in lung infection induced by Achromobacter xylosoxidans.Prado, Morgana Kelly Borges 24 February 2014 (has links)
Achromobacter xylosoxidans (A. xylosoxidans) é um bacilo gram negativo, aeróbio, móvel, não fermentador de glicose e oxidase positivo, que coloniza habitualmente o trato digestivo e auditivo de humanos. Este bacilo tem sido associado a infecções oportunistas graves, especialmente pneumonia, em indivíduos imunossuprimidos, que em geral, são de difícil controle devido principalmente a fatores de virulência, mecanismos de escape e mutirresistência a antibióticoterapia. Dentre as condições que predispõem o desenvolvimento de infecção pulmonar por A. xylosoxidans, o câncer, a fibrose cística (FC) e a doença pulmonar obstrutiva crônica (DPOC) são as mais comuns. Essas doenças apresentam produção aumentada de vários mediadores lipídicos, como LTB4 e PGE2. A PGE2 é um lipídeo imunossupressor atuante no sistema imune inato e adaptativo que regula, por exemplo, a liberação de citocinas e quimiocinas, a ativação de células T, além de inibir as funções efetoras dos macrófagos. O LTB4, por outro lado, está associado ao recrutamento de células para o foco infeccioso, a ativação dos mecanismos efetores dos macrófagos, e aumento de mediadores inflamatórios. Neste trabalho, nosso objetivo foi investigar se, esses mediadores são liberados durante a infecção pulmonar por A. xylosoxidans e o possível papel dos mesmos. Nossos resultados demonstram que os tratamentos com celecoxibe, inibidor da síntese de prostaglandinas (PGs), nas doses de 1mg/kg ou 5mg/kg, não alteram a sobrevida dos animais infectados com inóculo letal ou subletal de A. xylosoxidans. No entanto, o tratamento com MK886, um inibidor da produção de leucotrienos (LTs), resultou em aumento da mortalidade dos animais infectados com inóculos letal ou subletal, redução do recrutamento de neutrófilos no dia 1 após infecção, redução de IL-6 do dia 14 e aumento de TNF-, IL-1 e MIP-1 no dia 7, KC no dia 14 e PGE2, em todos os períodos estudados. Este tratamento também induziu no lavado broncoalveolar, a diminuição não significativa do extravasamento de proteínas no dia 1, mas aumento significativo no dia 3. Com base nesses dados, podemos sugerimos que o tratamento com MK886 aumenta a mortalidade dos animais, devido ao aumento da permeabilidade vascular, com consequente edema, que leva os animais a insuficiência respiratória. Outros experimentos serão realizados para determinar o papel das prostaglandinas (PGs) e/ou metabolitos do ácido araquidônico neste fenômeno. / Achromobacter xylosoxidans (A. xylosoxidans) is a gram negative bacilli, aerobic, mobile, glucose non fermenter and oxidase positive, which normally colonizes the digestive and auditory tract of humans. This bacillus has been associated with severe opportunistic infections, especially pneumonia, in immunocompromised individuals, which are generally difficult to control mainly due to virulence factors, mechanisms and exhaust multidrug resistance to antibiotic therapy. Among the conditions that predispose the development of pulmonary infection by A. xylosoxidans, cancer, cystic fibrosis (CF) and chronic obstructive pulmonary disease (COPD) are the most common. These diseases have increased production of various lipid mediators, such as LTB4 and PGE2. PGE2 is an immunosuppressive lipid active in the innate and adaptive immune system that regulates, for example, the release of cytokines and chemokines, activation of T cells and inhibits the effector functions of macrophages. LTB4, on the other hand, is associated with the recruitment of cells to the infection, and the activation of effector mechanisms of macrophages, and increased production of inflammatory mediators. In this study, our aim was to investigate whether these mediators are released during pulmonary infection by A. xylosoxidans and the possible role of the same. Our results demonstrate that treatment with celecoxib, prostaglandin synthesis inhibitor (PGs), at doses of 1mg/kg or 5mg/kg not alter the survival of animals infected with lethal or sublethal inoculum of A. xylosoxidans. However, treatment with MK886, an inhibitor of the production of leukotrienes (LTs) resulted in an increased mortality of the animals infected with lethal or sublethal inoculum, reduce the recruitment of neutrophils on day 1 after infection, reduction in IL-6 day 14 and increased TNF-, IL-1 and MIP-1 at day 7, KC in day 14 and PGE2 in all periods. This treatment also induced in the bronchoalveolar lavage, no significant decrease protein extravasation in the day 1, but significantly increased on day 3. Based on these data, we suggest that treatment with MK886 increases the mortality of animals due to increased vascular permeability, with consequent edema, which leads the animals to respiratory failure. Other experiments will be conducted to determine the role of prostaglandins (PGs) and/or metabolites of arachidonic acid in this phenomenon.
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Alterações anatomopatológicas em lobos-marinhos (Otariidae) encontrados na costa do Brasil / Anatomopathological changes in fur seals found ashore on the coast of BrazilReisfeld, Laura Chrispim 04 February 2016 (has links)
Diversas doenças emergentes, lesões e agentes infecciosos em mamíferos marinhos foram identificados pela primeira vez em animais encalhados. No Brasil, é comum a ocorrência de encalhes de lobos marinhos que se encontram debilitados e/ou enfermos. Devido à falta de estudos recentes que descrevam as principais causas de morte e alterações histopatológicas nos animais encalhados, o presente trabalho visa contribuir para a patologia comparada e, indiretamente, para a conservação de pinípedes por meio da investigação das principais lesões, enfermidades e causas de morte que acometem estas espécies no sul do Brasil. Para esse estudo, foram analisadas amostras de tecidos de 50 indivíduos de duas espécies de lobos marinhos: lobo-marinho-sul-americano (Arctocephalus australis) e lobo-marinho-subantártico (Artocephalus tropicalis), que foram encontrados ao longo da costa brasileira, incluindo cadáveres e animais recebidos vivos e que vieram a óbito em centros de reabilitação no Brasil. Essas amostras estão armazenadas no Banco de Tecido de Mamíferos Marinhos e foram avaliadas, identificadas e processadas no Laboratório de Histologia do VPT/FMVZ. Os achados histopatológicos que tiveram ocorrência superior ou igual a 30% foram: pneumonia (90%; 44/49), hiperplasia linfoide em linfonodo (59%; 19/32), congestão hepática (55%; 27/49), hiperplasia linfoide esplênica (55%; 24/44), edema pulmonar (53%; 26/49), enterite em intestino delgado (51%; 18/35), traqueíte (45%; 14/31), hepatite (43%; 21/49), enterite em intestino grosso (42%; 13/31), congestão pulmonar (33%; 16/49), expansão folicular em linfonodo (31%; 10/32) e glomerulonefrite membranosa (30%; 14/47). Dois casos de interesse especial foram reportados; um indíviduo de A. australis com possível causa de morte associada a meningoencefalite causada por protozoário da família Sarcocystidae e um indíviduo de A. tropicalis em que foi observado linfoma. Em uma análise geral, o principal sistema acometido foi o respiratório com 34% (17/50) dos casos, seguido por processos infecciosos, registrados em 28% (14/50) dos casos, sendo que infecções parasitárias por parafilaroides representaram 30,7% (4/13) das causas de morte de A. tropicalis. Dentre os infecciosos, a septicemia representou 42% (6/14) dos casos e foi reportada com maior frequência em A. australis. As outras causas de morte também observadas foram: nutricional (caquexia) 10% (5/50), indeterminada 10% (5/50), digestivo (enterite e hepatite) 6%(3/50), circulatório (choque) 6% (3/50), metabólico (estresse) 4% (2/50) e neoplasia (linfoma), observada em um único caso. Acreditamos que a análise dos dados obtidos no presente trabalho poderá fornecer um panorama sobre as doenças que indivíduos dessas espécies em vida livre possam apresentar em situações de encalhe e durante a reabilitação. Quantificar e entender as causas de encalhe de pinípedes irá fornecer importantes dados aos centros de reabilitação, que por sua vez, poderão utilizar essas informações para planejar cuidados veterinários adequados / Many emerging diseases, injuries and infectious agents in marine mammals have been identified for the first time in stranded animals. Stranding of fur seals that are weak and/or debilitated is common in Brazil. Due to lack of recent studies describing the main causes of death and histopathological changes in stranded animals, this paper aims to contribute to the comparative pathology and indirectly, for the conservation of pinnipeds, by investigating major injuries, illnesses and causes of death that affect these animals in southern Brazil. For this study, we analyzed tissue samples from 50 individuals from two species of sea lions: South American fur seal (Arctocephalus australis) and Sub-Antarctic fur seal (Artocephalus tropicalis), which were found along the Brazilian coast, including carcasses and animals that died in rehabilitation centers in Brazil. These samples are stored in the Marine Mammal Tissue Bank and were evaluated, identified and processed in the Laboratory of Histology (VPT/FMVZ). Histopathological findings that had occurrence equal to 30 % or higher were: pneumonia (90%; 44/49), lymphoid hyperplasia in lymph node (59%; 19/32), hepatic congestion (55%; 27/49), splenic lymphoid hyperplasia (55%; 24/44), pulmonary edema (53%; 26/49), small intestine enteritis (51%; 18/35), tracheitis (45%; 14/31), hepatitis (43%; 21/4 9), large intestine enteritis (42%; 13/31), pulmonary congestion (33%; 16/49), follicular expansion in lymph node (31%; 10/32) and membranous glomerulonephritis (30%; 14/47). Two cases of special interest were reported; one individual of A. australis, with cause of death possibly associated with meningoencephalitis caused by protozoa of Sarcocystidae family, and one individual of A. tropicalis, where lymphoma was observed. In an overview, the main affected system was respiratory with 34% (17/50) of the cases, followed by infectious processes, recorded in 28% (14/50) of the cases, in which Parafilaroides parasitic infections accounted for 30.7% (4/13) of the causes of death for A. tropicalis. Among the infectious process, septicemia accounted for 42% (6/14) of the cases and was more frequently reported in A. australis. Other causes of death that were also observed were: Nutritional (cachexia) 10% (5/50), undetermined 10% (5/50), digestive (enteritis and hepatitis) 6% (3/50), circulatory (shock) 6% (3/50), metabolic (stress) 4% (2/50) and neoplasia (lymphoma), observed in a single case. We believe that the analysis of the data obtained in this study may provide an overview of the diseases that wild individuals of these species can present in stranding situations and during rehabilitation. Quantifying and understanding the causes of strandings in pinnipeds, will provide important data for rehabilitation centers, which in turn may use this information to plan appropriate veterinary care
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Dinâmica de fagócitos sanguíneos e alveolares em bezerros com mannheimiose / Dynamics of blood and alveolar phagocytes in calves with mannheimioseBatista, Camila Freitas 11 September 2015 (has links)
A Mannheimia haemolytica é uma importante bactéria relacionada ao Complexo Doença Respiratória dos Bovinos e a essa atribui-se uma evolução para uma forma grave de pneumonia fibrinonecrótica. É considerada um habitante comensal da nasofaringe que em situações de comprometimento da resposta imune adquire um perfil oportunista. O presente estudo buscou observar por meio de modelo de infecção experimental, as possíveis alterações locais e sistêmicas causadas pela M. haemolytica em bezerros experimentalmente inoculados. Dessa forma seria possível de maneira longitudinal, acompanhar a dinâmica dos principais aspectos de defesa das vias aéreas posteriores durante a infecção e após o tratamento com o antimicrobiano norfloxacina associado ou não à flunexina meglumina. Avaliou-se por exame físico acrescido de broncoscopia, alterações funcionais das células de defesa e mediadores inflamatórios, tanto séricos quanto locais e a atividade in vitro da norfloxacina sobre a função dos fagócitos sanguíneos e do lavado broncoalveolar (LBA). Para tal foram utilizados 12 bezerros sadios que foram experimentalmente infectados por M. haemolytica dos quais foram avaliadas as alterações clínicas e, quantitativamente e funcionalmente, as populações leucocitárias no sangue e no LBA, assim como o efeito da norfloxacina sobre a atividade funcional dos fagócitos no sangue e no LBA. Os resultados do presente estudo demonstraram o sucesso da infecção experimental por M. haemolytica pelos achados clínicos, broncoscópicos e citológicos. Ademais, a infecção experimental por M. haemolytica foi associada a alterações nas subpopulações de linfócitos T CD8+ e уδ, na produção intracelular de espécies reativas de oxigênio (ERO), fagocitose e viabilidade pelas células CD14+ sanguíneas e do LBA e granulócitos do sangue e, expressão de L-selectina pelos leucócitos polimorfonucleares do sangue. Nenhuma alteração evidente foi observada na expressão de citocinas IL-1β, IL-8 e TNF-α nas células sanguíneas e do LBA. O tratamento com antimicrobiano associado ou não ao anti-inflamatório foi capaz de curar a infecção e reestabelecer os parâmetros avaliados à sua condição basal. Portanto, não se observou benefícios com a utilização adicional do anti-inflamatório no reestabelecimento do quadro clínico e da resposta imune neste experimento. Contudo, apesar de algumas alterações na resposta sistêmica durante o quadro infeccioso, as alterações locais foram mais perceptíveis. Outro aspecto importante encontrado foi o efeito in vitro da norfloxacina na produção intracelular de ERO, fagocitose bacteriana pelas células CD14+ sanguíneas e do LBA e em leucócitos polimorfonucleares no sangue. Conclui-se que as alterações funcionais dos fagócitos apresentaram papel importante na patogenia da mannheimiose, que foram condizentes com os achados clínicos da mannheimiose e da evolução do tratamento quando realizado no início do processo nosológico. / Mannheimia haemolytica is an important bacterial pathogen associated with Bovine Respiratory Disease Complex (BRDC) and it is believed to be the predominant cause of the disease’s evolution into a fibrinonecrotic pneumonia. A commensal inhabitant of the nasopharynx, M. haemolytica acts as an opportunist when host defenses are compromised. This study used an experimental infection model to investigate the possible local and systemic changes caused by M. haemolytica in inoculated calves. It sought to linearly follow the dynamics of the lower respiratory tract defense mechanisms, during the course of infection and after treatment with the antibacterial norfloxacin, which was administrated both with and without the anti-inflammatory flunixin meglumine. With clinical examination followed by bronchoscopy, this study evaluated the physiological modifications in defense cells and mediators of inflammation, and the in vitro influence of norfloxacin on phagocytes from the peripheral blood and Bronchoalveolar Lavage Fluid (BLF). Twelve (12) healthy calves were infected with M. haemolytica and posteriorly physically examined, and had samples of white cells from the peripheral blood and BLF analyzed for changes in count and physiology, further, the norfloxacin effect on phagocytes from the peripheral blood and BLF was also studied. The experimental infection proved itself to be successful based on clinical, bronchoscopic and cytological findings. Furthermore, the M. haemolytica experimental infection was associated with modifications in the subpopulations of lymphocytes CD8+ and уδ T cells, in intracellular production of Reactive Oxygen Species (ROS), viability and phagocytosis activity of CD14+ cells from the peripheral blood and BLF and granulocytes from the peripheral blood. No obvious change was observed in the expression of cytokines IL-1β, IL-8 e TNF-α by cells from the peripheral blood or BLF. The treatment with the antibacterial agent, with or without the anti-inflammatory, was proved to be successful in curing the disease, thus, the addition of an anti-inflammatory was considered unnecessary to revert the clinical infection and in the immune response. Although there was a systemic response during the course of infection, the local response was more noticeable. Another key finding of the present study was the in vitro effect of norfloxacin on the intracellular production of ROS and on phagocytosis activity of CD14+ cells from the peripheral blood and BLF and granulocytes from the peripheral blood. In conclusion, the functional changes in phagocytes play an important role in the pathogenesis of pulmonary infection caused by M. haemolytica, as they were consistent with the clinical findings of mannheimiosis and with the treatment when it was administrated in the beginning of the infection.
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