• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 50
  • 47
  • 7
  • 5
  • 4
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 143
  • 20
  • 17
  • 17
  • 15
  • 15
  • 15
  • 14
  • 13
  • 12
  • 10
  • 10
  • 10
  • 9
  • 9
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
131

Maternal-infant Predictors of Attendance at Neonatal Follow-up Programs

Ballantyne, Marilyn 04 August 2010 (has links)
Attendance at Neonatal Follow-up (NFU) programs is crucial for parents to gain access to timely diagnostic expertise, psychosocial support, and referral to needed services for their infants. Although NFU programs are considered beneficial, up to 50% of parents do not attend these programs with their infants. Non-attending infants have poorer outcomes (e.g., higher rates of disabilities and less access to required services) as compared to attenders. The purpose was to determine factors that predicted attendance at NFU. Naturally occurring attendance was monitored and maternal-infant factors including predisposing, enabling, and needs factors were investigated, guided by the Socio-Behavioral Model of Health Services Use. A prospective two-phase multi-site descriptive cohort study was conducted in 3 Canadian Neonatal Intensive Care Units that refer to 2 NFU programs. In Phase 1, standardized questionnaires were completed by 357 mothers (66% response rate) prior to their infant’s (N= 400 infants) NICU discharge. In Phase 2, attendance patterns at NFU were followed for 12 months. Higher maternal stress at the time of the infant’s NICU hospitalization was predictive of attendance at NFU. Parenting alone, more worry about maternal alcohol or drug use, and greater distance to NFU were predictive of non-attendance at NFU. Attendance at NFU decreased over time from 84% at the first appointment to 74% by 12 months. Two distinct attendance patterns emerged: no or minimal attendance (18.5%) and attendance at all or the majority of scheduled appointments (81.5%). The most frequent point of withdrawal from NFU occurred between NICU discharge and the first scheduled appointment; followed by drop-out following the first NFU appointment. These results provide new insight into patterns of attendance and the maternal-infant factors that characterize attenders/non-attenders at NFU and serve as the critical first step in developing interventions targeted at improving attendance, infant outcomes, and reporting of developmental sequelae.
132

Sulphur Amino Acid Requirement and Metabolism in the Total Parenteral Nutrition (TPN) Fed Human Neonate

Courtney-Martin, Glenda 23 September 2009 (has links)
Except for tyrosine, the amino acid requirement of parenterally fed (PN) human neonates has not been derived. Methionine and cysteine are indispensable and dispensable sulphur amino acids respectively. Cysteine is synthesized from methionine. Cysteine is unstable in solution, and is left out or added in very small amounts to amino acid solutions. Methionine is added to compensate for the lack of cysteine, assuming that the neonate will convert methionine to cysteine to meet the body’s metabolic demand. Methionine is hepatotoxic and there is evidence that the neonate has limited ability for its conversion to cysteine. To determine the requirement of the neonate for methionine, PN-fed, stable, post-surgical neonates received graded intakes of methionine. The mean methionine requirement was estimated to be 49 mg.kg-1.day-1, which is 48 to 90% of the methionine content of current commercial amino acid solutions. Because cysteine is the rate limiting substrate for glutathione (GSH) synthesis and current methods of determining amino acid requirement measure requirement for protein synthesis, SAA requirements for maintenance of GSH status was deleniated in healthy adult males and in PN-fed human neonates. GSH kinetics was measured in healthy men receiving the mean methionine requirement and graded intakes of cysteine. GSH synthesis did not change with the addition of cysteine. Additionally, PN-fed post-surgical neonates recieved a methionine-adequate cysteine-free PN followed by cysteine supplemented PN for two 3-day periods and GSH kinetics measured on days 3 and 6. There was no change in GSH synthesis in response to cysteine supplementation. It is concluded that the PN-fed human neonate is capable of synthesizing enough cysteine from methionine not only for protein synthesis but for GSH synthesis. For both healthy men and stable post-surgical neonates, the requirement for GSH synthesis is met at the sulphur amino acid requirement derived using the indicator amino acid technique
133

Sulphur Amino Acid Requirement and Metabolism in the Total Parenteral Nutrition (TPN) Fed Human Neonate

Courtney-Martin, Glenda 23 September 2009 (has links)
Except for tyrosine, the amino acid requirement of parenterally fed (PN) human neonates has not been derived. Methionine and cysteine are indispensable and dispensable sulphur amino acids respectively. Cysteine is synthesized from methionine. Cysteine is unstable in solution, and is left out or added in very small amounts to amino acid solutions. Methionine is added to compensate for the lack of cysteine, assuming that the neonate will convert methionine to cysteine to meet the body’s metabolic demand. Methionine is hepatotoxic and there is evidence that the neonate has limited ability for its conversion to cysteine. To determine the requirement of the neonate for methionine, PN-fed, stable, post-surgical neonates received graded intakes of methionine. The mean methionine requirement was estimated to be 49 mg.kg-1.day-1, which is 48 to 90% of the methionine content of current commercial amino acid solutions. Because cysteine is the rate limiting substrate for glutathione (GSH) synthesis and current methods of determining amino acid requirement measure requirement for protein synthesis, SAA requirements for maintenance of GSH status was deleniated in healthy adult males and in PN-fed human neonates. GSH kinetics was measured in healthy men receiving the mean methionine requirement and graded intakes of cysteine. GSH synthesis did not change with the addition of cysteine. Additionally, PN-fed post-surgical neonates recieved a methionine-adequate cysteine-free PN followed by cysteine supplemented PN for two 3-day periods and GSH kinetics measured on days 3 and 6. There was no change in GSH synthesis in response to cysteine supplementation. It is concluded that the PN-fed human neonate is capable of synthesizing enough cysteine from methionine not only for protein synthesis but for GSH synthesis. For both healthy men and stable post-surgical neonates, the requirement for GSH synthesis is met at the sulphur amino acid requirement derived using the indicator amino acid technique
134

Newborn EEG seizure detection using adaptive time-frequency signal processing

Rankine, Luke January 2006 (has links)
Dysfunction in the central nervous system of the neonate is often first identified through seizures. The diffculty in detecting clinical seizures, which involves the observation of physical manifestations characteristic to newborn seizure, has placed greater emphasis on the detection of newborn electroencephalographic (EEG) seizure. The high incidence of newborn seizure has resulted in considerable mortality and morbidity rates in the neonate. Accurate and rapid diagnosis of neonatal seizure is essential for proper treatment and therapy. This has impelled researchers to investigate possible methods for the automatic detection of newborn EEG seizure. This thesis is focused on the development of algorithms for the automatic detection of newborn EEG seizure using adaptive time-frequency signal processing. The assessment of newborn EEG seizure detection algorithms requires large datasets of nonseizure and seizure EEG which are not always readily available and often hard to acquire. This has led to the proposition of realistic models of newborn EEG which can be used to create large datasets for the evaluation and comparison of newborn EEG seizure detection algorithms. In this thesis, we develop two simulation methods which produce synthetic newborn EEG background and seizure. The simulation methods use nonlinear and time-frequency signal processing techniques to allow for the demonstrated nonlinear and nonstationary characteristics of the newborn EEG. Atomic decomposition techniques incorporating redundant time-frequency dictionaries are exciting new signal processing methods which deliver adaptive signal representations or approximations. In this thesis we have investigated two prominent atomic decomposition techniques, matching pursuit and basis pursuit, for their possible use in an automatic seizure detection algorithm. In our investigation, it was shown that matching pursuit generally provided the sparsest (i.e. most compact) approximation for various real and synthetic signals over a wide range of signal approximation levels. For this reason, we chose MP as our preferred atomic decomposition technique for this thesis. A new measure, referred to as structural complexity, which quantifes the level or degree of correlation between signal structures and the decomposition dictionary was proposed. Using the change in structural complexity, a generic method of detecting changes in signal structure was proposed. This detection methodology was then applied to the newborn EEG for the detection of state transition (i.e. nonseizure to seizure state) in the EEG signal. To optimize the seizure detection process, we developed a time-frequency dictionary that is coherent with the newborn EEG seizure state based on the time-frequency analysis of the newborn EEG seizure. It was shown that using the new coherent time-frequency dictionary and the change in structural complexity, we can detect the transition from nonseizure to seizure states in synthetic and real newborn EEG. Repetitive spiking in the EEG is a classic feature of newborn EEG seizure. Therefore, the automatic detection of spikes can be fundamental in the detection of newborn EEG seizure. The capacity of two adaptive time-frequency signal processing techniques to detect spikes was investigated. It was shown that a relationship between the EEG epoch length and the number of repetitive spikes governs the ability of both matching pursuit and adaptive spectrogram in detecting repetitive spikes. However, it was demonstrated that the law was less restrictive forth eadaptive spectrogram and it was shown to outperform matching pursuit in detecting repetitive spikes. The method of adapting the window length associated with the adaptive spectrogram used in this thesis was the maximum correlation criterion. It was observed that for the time instants where signal spikes occurred, the optimal window lengths selected by the maximum correlation criterion were small. Therefore, spike detection directly from the adaptive window optimization method was demonstrated and also shown to outperform matching pursuit. An automatic newborn EEG seizure detection algorithm was proposed based on the detection of repetitive spikes using the adaptive window optimization method. The algorithm shows excellent performance with real EEG data. A comparison of the proposed algorithm with four well documented newborn EEG seizure detection algorithms is provided. The results of the comparison show that the proposed algorithm has significantly better performance than the existing algorithms (i.e. Our proposed algorithm achieved a good detection rate (GDR) of 94% and false detection rate (FDR) of 2.3% compared with the leading algorithm which only produced a GDR of 62% and FDR of 16%). In summary, the novel contribution of this thesis to the fields of time-frequency signal processing and biomedical engineering is the successful development and application of sophisticated algorithms based on adaptive time-frequency signal processing techniques to the solution of automatic newborn EEG seizure detection.
135

Chlamydia trachomatis infections in neonates and infants

Honkila, M. (Minna) 18 September 2018 (has links)
Abstract Around 3% of pregnant women in Finland have genital Chlamydia trachomatis infection, which can be transmitted from mother to newborn at birth. The risk of transmission has been reported to be 10–70% in vaginal deliveries resulting in conjunctivitis in 10–30% of cases and lower respiratory tract infection in 0–20% of cases. Although usually benign, Chlamydia trachomatis infections in infancy may result in long-term consequences, including conjunctival and corneal scarring, chronic cough and abnormal lung function. Based on the transmission rates published in prior studies, chlamydial conjunctivitis should occur in approximately 200 infants and chlamydial lower respiratory tract infection in 100 infants each year in our country, but in clinical practice we rarely encounter or diagnose infants with Chlamydia trachomatis infections. To investigate the reason for this discrepancy and to improve the recognition of Chlamydia trachomatis-infected infants, we set out to study the risk of vertical transmission of Chlamydia trachomatis in a population-based setting, to describe the typical features of Chlamydia trachomatis infections in infants and to evaluate the occurrence of Chlamydia trachomatis in both neonatal conjunctivitis and lower respiratory tract infections in infants. When studying the probability of vertical transmission of Chlamydia trachomatis a search through two national health registers for 1996–2011 yielded 206 children aged less than four years with a possible Chlamydia trachomatis infection. In a cohort of 933 823 births this represented an occurrence of 0.22 per 1000 live births (95% confidence interval 0.19–0.25). The risk of vertical transmission of Chlamydia trachomatis leading to a symptomatic infection in infancy was 0.8–1.8%. A review of patient charts to evaluate the typical features of Chlamydia trachomatis infections in infants (124/206) revealed that one-third of the infants with chlamydial conjunctivitis (33/124) had spontaneous bloody discharge from the infected eyes. Almost half of the infants with chlamydial lower respiratory tract infection (15/32) had wheezing, but the characteristic staccato cough was not recorded in any of them. The median diagnostic delay from the onset of symptoms was 13 (range 4–374) days for conjunctivitis and 25 (range 10–149) days for lower respiratory tract infection. One neglected child developed bilateral corneal scars due to untreated chlamydial conjunctivitis. To investigate the occurrence of Chlamydia trachomatis in neonatal conjunctivitis, 173 neonates with clinical conjunctivitis at child health clinics were examined prospectively during 2010–2015 and none of the 163 cases tested had chlamydial or gonococcal conjunctivitis (0%; 95% confidence interval 0%–2.2%). Viral conjunctivitis was diagnosed in 8/167 cases (4.8%; 95% confidence interval 2.1%–9.2%) and non-chlamydial bacterial conjunctivitis in 58/160 (36%; 95% confidence interval 29%–44%). To investigate the occurrence of Chlamydia trachomatis in lower respiratory tract infections, 228 infants aged less than six months with lower respiratory tract infection presenting at the paediatric emergency department of Oulu University Hospital were examined prospectively over a period of a complete epidemiological year. One infant (0.4%; 95% confidence interval 0.01%–2.4%) had lower respiratory tract infection caused by Chlamydia trachomatis and another was diagnosed with whooping cough (0.4%; 95% confidence interval 0.01%–2.4%). The majority of the infants with lower respiratory tract infection (203/228) had a respiratory viral infection. It may be concluded that the risk of mother-to-child transmission of Chlamydia trachomatis leading to a clinical illness in the infant in this era of nucleic acid-based diagnostics was less than 2%, which is significantly lower than in earlier studies. The population-based prevalence of neonatal chlamydial conjunctivitis in primary care was less than 2% and that of chlamydial lower respiratory tract infection in a hospital setting less than 2.5%. The long-term prognosis for Chlamydia trachomatis infections in infancy was good. Common respiratory viruses were detected in 5% of the neonatal conjunctivitis cases. / Tiivistelmä Noin 3 %:lla suomalaisista raskaana olevista naisista on klamydian (Chlamydia trachomatis) aiheuttama sukupuolitauti, joka voi tarttua äidistä lapseen synnytyksessä. Tartuntariskin on raportoitu olevan alatiesynnytyksessä noin 10–70 %. Noin 10–30 % tartunnan saaneista lapsista sairastuu silmätulehdukseen ja 0–20 % keuhkokuumeeseen. Vaikka imeväisten klamydiainfektiot ovat useimmiten lieviä tauteja, imeväisiällä sairastettu klamydiainfektio voi aiheuttaa silmän side- ja sarveiskalvon arpeutumista, pitkittynyttä yskää ja keuhkofunktion alenemaa. Aiempien tutkimusten perusteella arvioimme, että Suomessa sairastuu vuosittain noin 200 imeväistä klamydian aiheuttamaan silmätulehdukseen ja noin 100 imeväistä klamydiakeuhkokuumeeseen. Kliininen kokemuksemme on kuitenkin, että kohtaamme klamydiaa sairastavia imeväisiä varsin harvoin. Tämän ongelman ratkaisemiseksi ja klamydiaa sairastavien imeväisten paremmaksi tunnistamiseksi suunnittelimme tutkimuksen, jonka tarkoituksena on selvittää väestöpohjainen riski klamydian tarttumiselle äidistä vastasyntyneeseen, kuvata imeväisten klamydiainfektioiden tyypilliset piirteet sekä selvittää klamydian osuus imeväisten silmätulehduksissa ja alle kuuden kuukauden ikäisten imeväisten alahengitystieinfektioissa. Klamydian sairastaneet lapset poimittiin kahdesta suomalaisesta terveydenhuoltorekisteristä vuosina 1996–2011. Tuona aikana 206 lasta oli sairastanut mahdollisen klamydiainfektion, joten klamydian ilmaantuvuus oli 0,22/1000:tta elävänä syntynyttä kohti (95 % luottamusväli 0,19–0,25). Väestöpohjainen riski äidin sukupuoliklamydian tarttumiselle vastasyntyneeseen niin että lapselle aiheutuu oireinen infektio oli 0,8–1,8 %. Saatavilla olevien potilasasiakirjojen (124/206) perusteella kolmasosalla (33/124) imeväisistä, jotka sairastivat klamydian aiheuttamaa silmätulehdusta, oli oireena spontaani verinen kyynel- tai rähmäerite. Klamydiakeuhkokuumetta sairastavista puolella (15/32) esiintyi hengityksen vinkumista, mutta klamydiakeuhkokuumeelle tyypillistä hakkaavaa yskää (”staccato-yskä”) ei todettu yhdelläkään imeväisellä. Diagnostinen viive oli verrattain pitkä: 13 päivää (vaihteluväli 4–374) silmätulehduksessa ja 25 päivää (vaihteluväli 10–149) keuhkokuumeessa. Yhdelle laiminlyödylle lapselle kehittyi molemminpuoliset sarveiskalvoarvet hoitamattoman klamydiainfektion seurauksena. Vastasyntyneen silmätulehdustutkimukseen rekrytoitiin 173 alle 30 päivän ikäistä lasta Oulun kaupungin lastenneuvoloissa vuosina 2010–2015. Klamydian tai tippurin aiheuttamaa silmätulehdusta ei todettu yhdelläkään 163:sta tutkitusta vauvasta (0 %; 95 % luottamusväli 0 %–2,2 %). Viruksen aiheuttama silmätulehdus todettiin kahdeksalla vauvalla (4,8 %; 95 % luottamusväli 2,1 %–9,2 %) ja jonkin muun bakteerin kuin klamydian aiheuttama silmätulehdus 58:lla vauvalla (36 %; 95 % luottamusväli 29 %–44 %). Imeväisten alahengitystieinfektiotutkimukseen rekrytoitiin 228 alle kuuden kuukauden ikäistä imeväistä yliopistosairaalan lastenpäivystyksessä yhden epidemiologisen vuoden aikana. Klamydian aiheuttama hengitystieinfektio diagnosoitiin yhdellä imeväisellä (0,4 %; 95 % luottamusväli 0,01 %–2,4 %) ja hinkuyskä niin ikään yhdellä (0,4 %; 95 % luottamusväli 0,01 %–2,4 %). Valtaosalla (203/228) alahengitystieinfektio-oireisista imeväisistä oli viruksen aiheuttama infektio. Yhteenvetona voimme todeta, että klamydia tarttui äidistä lapseen alle 2 %:ssa synnytyksistä, mikä on huomattavasti harvinaisempaa kuin aiemmin on luultu. Klamydian aiheuttamien silmätulehdusten esiintyvyys oli alle 2 % ja alahengitystieinfektioiden alle 2,5 % alueemme lapsiväestössä. Klamydian aiheuttamat pitkäaikaishaitat olivat harvinaisia. Tavallisten hengitystievirusten osuus vastasyntyneiden silmätulehduksissa oli 5 %.
136

Influência das alterações imunes em gestantes infectadas pelo HIV-1 no perfil funcional das células T de neonatos não infectados / Impact of immune alterations in pregnant women infected with HIV-1 in the functional profile of T cells from uninfected newborns

Joana Hygino da Silva Machado 19 August 2013 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O número de mulheres jovens infectadas pelo HIV-1 vem crescendo desde o início da epidemia da aids, principalmente nos países em desenvolvimento, onde a frequência de gravidez é elevada. O desenvolvimento de estratégias para evitar a transmissão vertical tem aumentado o número de recém-nascidos não infectados nascidos de gestantes portadora do vírus. O objetivo da presente tese foi avaliar, in vivo e in vitro, o perfil de citocinas de neonatos não infectados, porém nascidos de mulheres infectadas pelo HIV-1. Os resultados demonstraram elevados níveis de citocinas pró-inflamatórias relacionadas ao fenótipo Th17, associadas à baixa produção de IL-10, tanto nos plasmas quanto nos sobrenadantes das culturas de células T ativadas obtidas do sangue do cordão umbilical de neonatos nascidos de gestantes infectadas pelo HIV-1 com cargas virais plasmáticas(PVL) detectáveis. De modo interessante, um perfil similar pró-inflamatório foi observado em amostras de sangue periférico de suas respectivas mães. Por outro lado, níveis elevados de IL-10, associados à reduzida produção de citocinas inflamatórias, foram dosados no sangue e nos sobrenadantes das culturas de células T ativadas de gestantes que controlavam a PVL, assim como de seus neonatos. Com relação à caracterização fenotípica das células T maternas produtoras de IL-10, a análise por citometria de fluxo demonstrou que essa citocina é majoritariamente produzida por células T CD4+Foxp3-. Curiosamente, a replicação viral in vitro do HIV-1 foi inferior nas culturas das gestantes infectadas pelo HIV-1 e foi relacionada aos efeitos inibitórios da IL-10 sobre a produção de TNF-α. Por fim, os neonatos não infectados expostosin utero à terapia antirretroviral (ART) apresentaram um menor peso ao nascer, e este achado foi inversamente correlacionado com os níveis periféricos maternos de TNF-α. Em conclusão, nossos achados sugerem que gestantes que conseguem controlar a PVL, e o incremento na produção de IL-10 materna possam favorecer a expansão das células Tr-1, as quais podem auxiliar em reduzir o risco de transmissão vertical do HIV-1 por reduzir a taxa de replicação viral. Por outro lado, outros resultados também apresentados aqui, apesar de preliminares, revelaram efeitos adversos da replicação viral e da ART em gestantes infectadas pelo HIV-1 no desenvolvimento funcional das células T de neonatos não infectados. Esses dados podem ajudar a explicar por que algumas dessas crianças apresentam elevado risco à morbidade e mortalidade devido a um estado basal de hipersensibilidade patológica. / The number of HIV-1-infected young women has been increasing since the beginning of the AIDS epidemic, mainly in developing countries, where the frequency of pregnancy among them is also elevated. The development of strategies for vertical transmission avoidance has enhanced the number of uninfected neonates born from infected mothers. The objective of the present study was to evaluate, in vivo and in vitro, the cytokine profile of uninfected neonates born from pregnant women infected with HIV-1.The results demonstrated high levels of proinflammatory cytokines related to Th17 phenotype associated with low IL-10 production, in plasma as well as in culture supernatants of activated T cells obtained from umbilical cord blood of neonates born from mothers infected with HIV -1 with plasma viral load (PVL) detectable.Interestingly, a similar pro-inflammatory cytokine profile was observed in peripheral blood samples from their respective mothers.On the other hand, high levels of IL-10 associated to reduced production of inflammatory cytokines were measured in blood and in the supernatants of activated T cells culturesfrom women that controlled the PVL, as well as their neonates.Regarding the phenotypic profile of pregnant women infected of HIV-1, the main T lymphocyte subset involved in producing IL-10 was CD4+Foxp3-. Interestingly, the in vitro HIV-1 replication was lower in cell cultures from pregnant patients, and it was related to the inhibitory effects of IL-10 on the production of TNF-α. Finally, ART-in utero-exposed neonates showed to be born with lower weight, and it was inversely correlated with maternal peripheral TNF-α level. In conclusion, the results suggest that pregnant women that are able to control the PVL, and the increment in the production of IL-10 may favor maternal Tr-1 cell expansion, which could help to reduce the risk of vertical transmission of HIV-1 by reducing the rate of viral replication.However, other results also presented here, although preliminary, have revealed adverse effects of viral replication, as well as the use of ART by pregnant women infected with HIV-1 in the development of functional T cells from uninfected newborns.These data may help to explain why some of these children have elevated risk of clinical morbidity and mortality due to a baseline state of pathological hypersensitivity.
137

Influência das alterações imunes em gestantes infectadas pelo HIV-1 no perfil funcional das células T de neonatos não infectados / Impact of immune alterations in pregnant women infected with HIV-1 in the functional profile of T cells from uninfected newborns

Joana Hygino da Silva Machado 19 August 2013 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O número de mulheres jovens infectadas pelo HIV-1 vem crescendo desde o início da epidemia da aids, principalmente nos países em desenvolvimento, onde a frequência de gravidez é elevada. O desenvolvimento de estratégias para evitar a transmissão vertical tem aumentado o número de recém-nascidos não infectados nascidos de gestantes portadora do vírus. O objetivo da presente tese foi avaliar, in vivo e in vitro, o perfil de citocinas de neonatos não infectados, porém nascidos de mulheres infectadas pelo HIV-1. Os resultados demonstraram elevados níveis de citocinas pró-inflamatórias relacionadas ao fenótipo Th17, associadas à baixa produção de IL-10, tanto nos plasmas quanto nos sobrenadantes das culturas de células T ativadas obtidas do sangue do cordão umbilical de neonatos nascidos de gestantes infectadas pelo HIV-1 com cargas virais plasmáticas(PVL) detectáveis. De modo interessante, um perfil similar pró-inflamatório foi observado em amostras de sangue periférico de suas respectivas mães. Por outro lado, níveis elevados de IL-10, associados à reduzida produção de citocinas inflamatórias, foram dosados no sangue e nos sobrenadantes das culturas de células T ativadas de gestantes que controlavam a PVL, assim como de seus neonatos. Com relação à caracterização fenotípica das células T maternas produtoras de IL-10, a análise por citometria de fluxo demonstrou que essa citocina é majoritariamente produzida por células T CD4+Foxp3-. Curiosamente, a replicação viral in vitro do HIV-1 foi inferior nas culturas das gestantes infectadas pelo HIV-1 e foi relacionada aos efeitos inibitórios da IL-10 sobre a produção de TNF-α. Por fim, os neonatos não infectados expostosin utero à terapia antirretroviral (ART) apresentaram um menor peso ao nascer, e este achado foi inversamente correlacionado com os níveis periféricos maternos de TNF-α. Em conclusão, nossos achados sugerem que gestantes que conseguem controlar a PVL, e o incremento na produção de IL-10 materna possam favorecer a expansão das células Tr-1, as quais podem auxiliar em reduzir o risco de transmissão vertical do HIV-1 por reduzir a taxa de replicação viral. Por outro lado, outros resultados também apresentados aqui, apesar de preliminares, revelaram efeitos adversos da replicação viral e da ART em gestantes infectadas pelo HIV-1 no desenvolvimento funcional das células T de neonatos não infectados. Esses dados podem ajudar a explicar por que algumas dessas crianças apresentam elevado risco à morbidade e mortalidade devido a um estado basal de hipersensibilidade patológica. / The number of HIV-1-infected young women has been increasing since the beginning of the AIDS epidemic, mainly in developing countries, where the frequency of pregnancy among them is also elevated. The development of strategies for vertical transmission avoidance has enhanced the number of uninfected neonates born from infected mothers. The objective of the present study was to evaluate, in vivo and in vitro, the cytokine profile of uninfected neonates born from pregnant women infected with HIV-1.The results demonstrated high levels of proinflammatory cytokines related to Th17 phenotype associated with low IL-10 production, in plasma as well as in culture supernatants of activated T cells obtained from umbilical cord blood of neonates born from mothers infected with HIV -1 with plasma viral load (PVL) detectable.Interestingly, a similar pro-inflammatory cytokine profile was observed in peripheral blood samples from their respective mothers.On the other hand, high levels of IL-10 associated to reduced production of inflammatory cytokines were measured in blood and in the supernatants of activated T cells culturesfrom women that controlled the PVL, as well as their neonates.Regarding the phenotypic profile of pregnant women infected of HIV-1, the main T lymphocyte subset involved in producing IL-10 was CD4+Foxp3-. Interestingly, the in vitro HIV-1 replication was lower in cell cultures from pregnant patients, and it was related to the inhibitory effects of IL-10 on the production of TNF-α. Finally, ART-in utero-exposed neonates showed to be born with lower weight, and it was inversely correlated with maternal peripheral TNF-α level. In conclusion, the results suggest that pregnant women that are able to control the PVL, and the increment in the production of IL-10 may favor maternal Tr-1 cell expansion, which could help to reduce the risk of vertical transmission of HIV-1 by reducing the rate of viral replication.However, other results also presented here, although preliminary, have revealed adverse effects of viral replication, as well as the use of ART by pregnant women infected with HIV-1 in the development of functional T cells from uninfected newborns.These data may help to explain why some of these children have elevated risk of clinical morbidity and mortality due to a baseline state of pathological hypersensitivity.
138

Perfil da utilização de medicamentos não licenciados e sem indicação para crianças em UTI neonatal de Hospital Universitário de média complexidade / The use of unlicensed and off label medicines for children admitted to the neonatal intensive care unit of a median complexity university Hospital in São Paulo

Sandra Cristina Brassica 03 November 2009 (has links)
Introdução. Medicamentos não licenciados e sem indicação são utilizados com grande frequência em pediatria por razões éticas e econômicas. A utilização destes medicamentos não constitui um preceito ilegal, mas pode oferecer risco aos pacientes, sendo responsabilidade do médico e do farmacêutico qualquer evento adverso ocasionado. Alguns estudos nesta população sugerem aumento do risco de reações adversas relacionadas ao uso de medicamentos fora das indicações licenciadas. Objetivo. Analisar a exposição a medicamentos não licenciados e sem indicação em neonatos admitidos em Unidade de Terapia Intensiva (UTINEO) em hospital universitário de média complexidade de São Paulo, Brasil. Método. Estudo descritivo transversal dos medicamentos prescritos nas primeiras 24 horas de internação para 79 pacientes admitidos na Unidade de Terapia Intensiva Neonatal, do Hospital Universitário da Universidade de São Paulo (HU-USP), campus de São Paulo, no período de 12/03/08 a 03/11/08. Os medicamentos foram classificados em não licenciados e sem indicação para utilização por população neonatal de acordo com critérios de registro brasileiros e americanos. Resultados: foram prescritos 346 medicamentos. De acordo com os critérios brasileiros de licenciamento 58% não estavam licenciados, 9,5% não eram indicados, sendo que 66 % dos pacientes foram expostos a ao menos 1 item não licenciado e 18% a pelo menos 1 item sem indicação. A avaliação com base nos critérios americanos demonstrou que 53% dos medicamentos não estavam licenciados, 10,9% não tinham indicação, sendo que 63% dos pacientes foram expostos a ao menos 1 item não licenciado e 20% a pelo menos 1 item sem indicação.Conclusões: Os neonatos brasileiros estão expostos a medicamentos não licenciados e sem indicação nas primeiras 24 horas de internação. Embora esforços tenham sido empregados em diversos países para diminuir tal prática, o problema não foi equacionado. No Brasil, ainda, há informações distintas em bulas de medicamentos licenciados e, em relação, aos medicamentos não licenciados ou sem indicação não há nenhuma política estabelecida. / Introduction. In pediatrics utilization of unlicensed an off-label drugs are a common practice and this account for ethical and economic reasons. The utilization of unlicensed and off label drugs is not illegal, but can expose patients to risk of harm. Physicians and pharmacists have legal responsibility for any adverse event that may result from this use. Some studies in the pediatric field suggest an increased risk to adverse reactions related to unlicensed and off label use. Objective. To assess the exposure to unlicensed and off-label medicines in neonates admitted to the Neonatal Intensive Care Unit (NICU) in a Brazilian medium complexity University Hospital. Materials and Methods. A cross sectional descriptive study was conducted of prescribed medicines in the first 24 hours of admission for 79 patients admitted to the Neonatal Intensive Care Unit (NICU) in the University Hospital of the University of São Paulo (HU-USP), campus of São Paulo in the period of 12/03/08 to 03/11/08. The medicines were classified as unlicensed and off-label for use in neonatal population according to the criteria for licensing of medicines in Brazil and US. Results: There were a total of 346 medicines prescribed and according to the established criteria in Brazil 58% were unlicensed, 9.5% were off-label; 66% of patients were exposed to at least 1 item unlicensed and 18% at least 1 item off-label. In relation to the criteria in USA 53% were not licensed, 10.9% were off-label, and 63% of patients were exposed to at least 1 item unlicensed and 20% at least 1 item off-label. Conclusions: Brazilian neonates are exposed to unlicensed and off-label medicines already in the first 24 hours of hospitalization. Although efforts have been employed in several countries to reduce this practice, the problem was not solved. In Brazil, there is even different information in leaflets for medicines licensed in and, in relation, to unlicensed or off-label medicines there is no established policy.
139

Study of the development of Th17-type immune response in early life / Etude du développement des réponses immunitaires de type Th17 en début de vie

Debock, Isabelle 23 May 2012 (has links)
Par rapport à l’adulte, le nouveau-né présente une susceptibilité accrue aux agents infectieux et au développement d’allergies. Une polarisation de l’immunité acquise vers des réponses de type Th2, productrices d’IL-4, d’IL-5 et d’IL-13, et un défaut de réponses immunes de type Th1, sécrétant de l’IFN-γ, peuvent rendre compte de ce statut immunitaire particulier. De plus, un retard de production et de maturation des anticorps, caractéristiques de l’immunité humorale, s’observe en début de vie. <p>Récemment, de nouveaux lymphocytes T auxiliaires ont été décrits, les lymphocytes Th17, producteurs d’IL-17A, d’IL-17F et d’IL-22, d’une part, et les lymphocytes Tfh, sécrétant de l’IL-21 et exprimant CXCR5, ICOS et PD-1, d’autre part. La différenciation des lymphocytes Th17 dépend de la présence d’IL-6 ou d’IL-21 et de TGF-β, et est inhibée par l’IL-4 ;tandis que les lymphocytes Tfh sont induits en présence d’IL-21, d’IL-6 et du répresseur transcriptionnel Bcl6. Alors que les lymphocytes Th17 sont associés à des réponses inflammatoires par le recrutement de neutrophiles, les lymphocytes Tfh aident les lymphocytes B à produire des anticorps de haute affinité.<p><p>L’objectif principal de notre travail est l’étude du développement potentiel de réponses de type Th17 chez le nouveau-né de souris soumis à une stimulation allogénique et au manque d’IL-4. De plus, l’existence potentielle de lymphocytes Tfh induits chez le nouveau-né immunisé avec un vaccin constitué d’ovalbumine de poulet et d’Alum, sera investiguée.<p><p>Dans notre modèle de tolérance néonatale, l’immunisation de nouveau-nés BALB/c à l’aide de cellules spléniques semi-allogéniques F1 (AJAX x BALB/c) induit une polarisation de type Th2, associée à l’établissement d’un chimérisme lymphoïde et à l’acceptation d’une greffe de peau présentant les alloantigènes rencontrés à la naissance. Des nouveau-nés soumis à cette immunisation allogénique et à la privation d’IL-4, réalisée par l’utilisation d’anticorps monoclonaux ou de souris IL-4-/-, rejettent de façon aiguë les greffons de peau et présentent une proportion réduite de cellules chimériques. Cette rupture de la tolérance néonatale est associée à l’inhibition de la réponse allospécifique de type Th2 et au développement de lymphocytes Th17 alloréactifs, produisant de l’IL-17A. L’inhibition de la voie Th17 ne conduit toutefois pas à l’acceptation des allogreffes de peau. Par contre, la neutralisation de l’IL-6 ou de l’IL-17A et la réduction du nombre de neutrophiles restaurent la proportion de cellules chimériques présentes dans la rate, démontrant que la réponse de type Th17 allospécifique néonatale contrôle le chimérisme lymphoïde. <p><p>En réponse au vaccin OVA-Alum, les nouveau-nés présentent une proportion accrue de lymphocytes Tfh CXCR5+ PD-1+, bien que cette proportion lymphocytaire soit significativement diminuée par rapport aux adultes. Les lymphocytes Tfh néonataux expriment en outre des taux moindres des ARNm d’IL-21, d’IL-4 et de Bcl6, suggérant que la génération de lymphocytes Tfh est altérée en début de vie. En parallèle, les titres et la maturation des anticorps produits suite à la vaccination sont réduits chez les nouveau-nés, en comparaison avec les adultes. Cependant, qu’ils soient déficients en IL-4 ou non, des lymphocytes T CD4+ néonataux activés in vitro en présence d’IL-6 induisent une production d’anticorps par des lymphocytes B compétents, suggérant qu’il n’y a pas de défaut intrinsèque des lymphocytes T du nouveau-né à développer une capacité d’aide aux lymphocytes B.<p><p>En conclusion, nous avons montré que la polarisation de type Th2 néonatale inhibe la différenciation de lymphocytes Th17 alloréactifs contrôlant le rejet de cellules allogéniques, un mécanisme pouvant intervenir dans la relation immunitaire entre la mère et l’enfant. Nos résultats indiquent également que le nouveau-né est capable de différencier des lymphocytes Tfh, bien que le développement de ces derniers semble réduit. \ / Doctorat en Sciences biomédicales et pharmaceutiques / info:eu-repo/semantics/nonPublished
140

Výchovné styly rodičů předčasně narozených dětí / Educational styles of parents of preterm children

Lukáčová, Monika January 2018 (has links)
BACKGROUND: The most numerous group from children due to perinatal burden is a group of prematurely born children and whose number continues to increase constantly. The children have higher probability of health problems and they are at risk of a complex threat to their successful development. Premature childbirth is a complicated difficult life situation for parents. Strongly reduced mental well- being is often developed at these parents and sometimes even some clinical symptoms (especially depression, anxiety, posttraumatic stress disorder). Such parenting (as well as other factors) greatly diminishes the overall interaction and communication with the child (especially their sensitivity and responsiveness) which can also be reflected in the parental style. AIM: The aim of the empirical part was to describe the occurrence of individual educational styles in healthy preterm infants 8-12 years old. METHODS: A Questionnaire of parental styles for children between the ages of 8 and 12 was used for this purpose (Čáp, Čechová & Boschek, 2000). RESULTS: A sample of 35 children showed that the most perceived parental style was a style characterized by a negative emotional relationship combined with a strong direction. CONCLUSION: The importance of the results can be seen in the practical application for...

Page generated in 0.3542 seconds