Schistosomiasis is a major parasitic disease caused by parasitic helminths of the genus Schistosoma which affects children in Africa, with negative impacts on general health, growth and cognitive development. Infection and morbidity are controlled by treatment with the antihelminthic drug praziquantel. Preschool children (aged ≤5 years old) have been neglected both in terms of research and control, and it is only recently that the World Health Organization (WHO) recommended praziquantel treatment and the inclusion of preschool children in control programmes. However, the burden of disease in this age group still remains poorly understood, and the performance of the currently available tools for detecting infection and morbidity is still yet to be systematically evaluated. The aim of this thesis was to compare the utility of currently available tools for diagnosing S. haematobium infection and related morbidity. The initial study cohort consisted of 438 Zimbabwean children (age range: 1-10 years) who were endemically exposed. Point-of-care schistosome-related morbidity markers applicable in the field, as well as serological biomarkers (CHI3L1, CRP, ferritin, resistin and SLPI) and inflammatory cytokines (IL-4, IL-5, IL-10, IL-13 and IFN-γ) that could predict early stages of immune-mediated pathology due to schistosomiasis were measured. Using a combination of applied statistical methods, the effect of treatment on factors associated with S. haematobium exposure, infection and morbidity in children aged 1-5 years was determined and the findings compared with those observed in children aged between 6-10 years old, who are the current targets of the schistosome control programmes. In this thesis, I able to demonstrate that preschool children carried significant infection, further reiterating the need for their inclusion in control programmes. Furthermore, this study demonstrated the importance of using additional sensitive diagnostic methods as this has implications on the required intervention strategies for the targeted populations. This study further revealed that preschool children can be effectively screened for schistosome-related morbidity using the same currently available diagnostic tools applicable to older children. Urinalysis markers microhaematuria, proteinuria and albuminuria are recommended in this thesis as the best choice for rapid assessment of morbidity attributed to S. haematobium infection in the field. Additionally, it was shown that the praziquantel treatment regimens aimed at controlling schistosome infection and morbidity currently designated for primary school-aged children and older populations are applicable to preschool-aged children. The involvement of serum biomarkers and immune correlates in the biological processes of inflammation suggests that these markers can be potential early predictors of schistosome-related pathology. Further research efforts are required to establish the relationship between these biomarkers and presence of schistosome-related morbidity as measured using point-of-care indicators in larger cohorts of populations chronically exposed to schistosome infections. In summary, the findings of this thesis highlight the need for the refinement of existing diagnostic methods for accurate detection of infection and morbidity in children. This will enable appropriate and timely intervention strategies, aimed at improving the current and future health of preschool aged-children to be implemented. The findings presented here will aid researchers and other stakeholders in making informed choices about intervention tools for control programmes targeting young children.

The influence of temperature on the bionomics of Bulinus (Physopsis) globosus, Biomphalaria pfeifferi and Lymnaea natalensis has been studied both in the laboratory under controlled conditions and in the field under normal seasonal influences. Field studies were carried out in two different localities, one a semi-permanent pond and the other a temporary waterbody. For this purpose a sampling implement was developed. The results show the seasonal progression of these populations both with respect to estimated numbers and the size distribution of the snails. The rate of actual increase at different seasons was calculated for the three species where the data were sufficient. In the laboratory the snails were maintained at various temperatures, other conditions being kept standard. Daily records of mortality and fecundity of various cohorts reared from the egg stage enabled the compilation of life tables fof the speciesand from these data were calcualted the intrinsic rate of natural increase and other parameters. Effects of crowding in aquaria were studied. From the data obtained in the laboratory it was possible to predict the distribution and population potential for each species for snail of various environmental conditions. These predictions were, in fact, confirmed by field observation.

In dieser Arbeit wurden Bewohner/-innen der Würzburger Gemeinschaftsunterkünfte für Geflüchtete auf das Vorliegen einer Schistosomiasis gescreent. Lag eine behandlungsdürftige Infektion vor, wurden die Teilnehmenden mit Praziquantel behandelt, um im nachfolgenden Verlauf freiwillig an der Erstellung einer Schistosomen-DNA-Kinetik mitzuwirken. Eine Besonderheit der Studie lag dabei in der fehlenden Möglichkeit einer Reinfektion, da sich die Betroffenen während des Follow-ups in einem Endemie-freien Gebiet aufhielten. Für das Screening kamen ein CCA-Urin-Schnelltest sowie ein ICT zum Einsatz. Die Diagnosesicherung wurde durch die Mikroskopie oder die qPCR angestrebt. Es zeigte sich, dass die Kombination von CCA-Test und ICT einen positiven prädiktiven Wert von 80 % für das tatsächliche Vorliegen einer Schistosomen-Infektion liefert. Die Schistosomiasis-Prävalenz der hier untersuchten, in einem Nicht-Endemiegebiet lebenden Risikopopulation, wurde auf 3,9 % bestimmt und ist im Vergleich zu bisherigen Veröffentlichungen als niedrig anzusehen. Dabei ist zu beachten, dass die Prävalenz zum Teil deutlich überschätzt werden kann, sofern der CCA-Urin-Schnelltest als alleiniges Diagnosekriterium eingesetzt wird (PrävalenzCCA = 27,6 %). Die Erstellung der DNA-Kinetik mittels qPCR zeigte, dass die Behandlung mit Praziquantel einen nach 3 Tagen messbaren, signifikanten (p < 0,05) Anstieg der DNA-Konzentration im Serum zur Folge hatte, welcher im weiteren Verlauf kontinuierlich abfiel. Im Mittel wurde nach 48 Tagen der Schwellenwert der DNA-Konzentration unterschritten, der ohne vorausgegangene Behandlung als positiv und therapiebedürftig gewertet worden wäre. Durch Inter- und Extrapolation der gewonnen Daten, konnte eine Funktion errechnet werden, die den zeitlichen Verlauf des Zerfalls der Schistosomen-DNA beschreibt und somit zur Ermittlung weiterer Therapie- und Kontrollmöglichkeit der Schistosomiasis beitragen kann. / Residents of the Würzburg communal accommodation for refugees were screened for the presence of schistosomiasis. If an infection requiring treatment was present, the participants were treated with praziquantel. After the intervention several serum samples were taken to determine schistosoma DNA kinetics. A special feature of the study was the lack of possibility of reinfection, since those affected stayed in an non-endemic area during the follow-up. A rapid CCA urine test and an ICT were used for the screening. The diagnosis was confirmed by microscopy or qPCR. It was shown that the combination of CCA test and ICT provides a positive predictive value of 80% for the actual presence of schistosoma infection. The schistosomiasis prevalence of the risk population was determined at 3.9% and can be regarded as low compared to previous publications. It should be noted that the prevalence can in some cases be significantly overestimated if the rapid CCA urine test is used as the single diagnostic criteria (CCA prevalence = 27.6%). The determination of the DNA kinetics using qPCR showed that the treatment with praziquantel resulted in a measurable, significant (p < 0.05) increase in the DNA concentration in the serum after 3 days, which continued to decrease over time. On average, after 48 days the DNA concentration had fallen below the threshold value that would have detected a treatment requiring infection. By interpolating and extrapolating the data, a function that describes the the decay of the schistosoma DNA over time was calculated and can therefor contribute to the determination of further therapy and control of schistosomiasis.

Lok Chui-Lin. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 142-157). / Abstracts in English and Chinese. / Statement --- p.I / Acknowledgement --- p.II / Abstract --- p.IV / Chinese Abstract (摘要） --- p.VI / Abbreviation --- p.VIII / Table of Contents --- p.XIII / List of Tables --- p.XVII / List of Figures --- p.XVIII / Chapter Chapter One : --- Literature Review --- p.1 / Chapter 1.1 --- The Schistosoma Species --- p.1 / Chapter 1.1.1 --- The Schistosoma Gene Discovery --- p.3 / Chapter 1.1.2 --- Schistosome Transcriptome --- p.4 / Chapter 1.2 --- Schistosomiasis --- p.4 / Chapter 1.2.1 --- Immunopathology of Schistosomiasis --- p.5 / Chapter 1.2.2 --- Diagnosis of Schistosomiasis --- p.7 / Chapter 1.2.3 --- Treatment and Control for Schistosomiasis --- p.7 / Chapter 1.2.4 --- Vaccine Development for Schistosomiasis --- p.8 / Chapter 1.3 --- "The Species, Schistosoma japonicum" --- p.9 / Chapter 1.3.1 --- The Life Cycle of Schistosoma japonicum --- p.10 / Chapter 1.3.1.1 --- "The Egg, Miracidium Phase of the Life Cycle" --- p.12 / Chapter 1.3.1.2 --- Developmental Cycle within Mollusc Host --- p.12 / Chapter 1.3.1.3 --- The Cercaria Phase of Life Cycle --- p.13 / Chapter 1.3.1.4 --- Adult Schistosome in Definitive Host --- p.14 / Chapter 1.4 --- Invasion by Schistosome Cercariae --- p.15 / Chapter 1.5 --- "The Anti-inflammatory Protein, Sml6" --- p.16 / Chapter 1.5.1 --- Discovery of Sm 16 --- p.16 / Chapter 1.5.2 --- Cloning and Expression of Gene-encoding Sm 16 --- p.17 / Chapter 1.5.3 --- Potential Anti-inflammatory Therapy using Sm 16 --- p.18 / Chapter 1.6 --- Innate Immunity and Adaptive Immunity --- p.18 / Chapter 1.6.1 --- Macrophage --- p.18 / Chapter 1.6.2 --- Major Histocompatiblity Complex (MHC) --- p.20 / Chapter 1.6.3 --- Adaptive Immunity to Parasites --- p.20 / Chapter 1.7 --- Inflammation --- p.21 / Chapter 1.7.1 --- Cells of the Inflammatory Process --- p.23 / Chapter 1.7.2 --- Cytokines --- p.24 / Chapter 1.7.2.1 --- Interleukin-1 (IL-1) System --- p.26 / Chapter 1.7.2.2 --- Interferon (IFN) System --- p.27 / Chapter 1.7.3 --- Anti-inflammatory Therapy --- p.28 / Chapter 1.8 --- Aim of Study --- p.29 / Chapter Chapter Two : --- Materials and Methods --- p.30 / Chapter 2.1 --- Materials --- p.30 / Chapter 2.1.1 --- "Cell Lines, Mouse Strain and Bacterial Strains" --- p.30 / Chapter 2.1.2 --- Plasmids --- p.31 / Chapter 2.1.3 --- Chemicals --- p.31 / Chapter 2.1.4 --- "Kits, Nucleic Acids and Reagents" --- p.34 / Chapter 2.1.5 --- Antibodies and Immunoglobins --- p.35 / Chapter 2.1.6 --- Cell Culture Reagents --- p.35 / Chapter 2.1.7 --- Solutions --- p.36 / Chapter 2.1.8 --- Solutions of Reaction Kits --- p.39 / Chapter 2.1.9 --- Enzymes --- p.41 / Chapter 2.1.10 --- Major Equipments and Materials --- p.41 / Chapter 2.1.11 --- Primers --- p.43 / Chapter 2.1.11.1 --- Sequencing and Sj 16 Gene-coding Specific Primers --- p.43 / Chapter 2.1.11.2 --- Primers for Cytokines --- p.43 / Chapter 2.2 --- Methods --- p.45 / Chapter 2.2.1 --- Amplification of Sjl6 cDNA from Schistosoma japonicum Cercariae --- p.45 / Chapter 2.2.1.1 --- Isolation of Cercariae total RNA by Guanidinium Thiocyanate - Cesium Chloride Ultracentrifugation --- p.45 / Chapter 2.2.1.2 --- Reverse Transcription - Polymerase Chain Reaction (RT-PCR) --- p.46 / Chapter 2.2.1.2.1 --- Reverse Transcription (RT) --- p.46 / Chapter 2.2.1.2.2 --- Polymerase Chain Reaction (PCR) --- p.46 / Chapter 2.2.2 --- Cloning and Subcloning of Sj 16 --- p.47 / Chapter 2.2.2.1 --- Preparation of DH5a Competent Cells --- p.47 / Chapter 2.2.2.2 --- Purification of Plasmid DNA --- p.48 / Chapter 2.2.2.3 --- Restriction Enzyme Digestion of DNA --- p.49 / Chapter 2.2.2.4 --- Purification of DNA Fragments from Agarose Gel --- p.50 / Chapter 2.2.2.5 --- Ligation of Purified DNA Fragments --- p.51 / Chapter 2.2.2.6 --- Transformation of Recombinant Plasmid --- p.52 / Chapter 2.2.2.7 --- Selection of Transformed Clones --- p.52 / Chapter 2.2.2.7.1 --- Screening by X-gal and IPTG : a-complementation --- p.52 / Chapter 2.2.2.7.2 --- Screening by Polymerase Chain Reaction --- p.53 / Chapter 2.2.2.8 --- Cycle Sequencing --- p.53 / Chapter 2.2.3 --- Expression of the rSj 16 in Eukaryotic System --- p.55 / Chapter 2.2.3.1 --- Transfection of pSecTag2B/Sj 16 Plasmid into Animal Cells --- p.55 / Chapter 2.2.3.2 --- PCR Screening of Transfected Cells --- p.56 / Chapter 2.2.3.3 --- Analysis of mRNA Transcript by RT-PCR --- p.56 / Chapter 2.2.3.4 --- Concentration of the Condition Medium --- p.57 / Chapter 2.2.3.5 --- Western Blot analysis of rSjl6 Expression --- p.58 / Chapter 2.2.4 --- Expression of rSjl6 in Bacterial System --- p.59 / Chapter 2.2.4.1 --- Transformation of pET30a+/Sjl6 Plasmid into BL21 --- p.59 / Chapter 2.2.4.2 --- Optimization of rSj 16 Expression --- p.60 / Chapter 2.2.4.3 --- Solubility of the rSjl6 --- p.60 / Chapter 2.2.4.4 --- Estimation of rSj 16 Concentration --- p.62 / Chapter 2.2.4.5 --- Western Blot Analysis of rSj 16 --- p.62 / Chapter 2.2.5 --- Recombinant Protein Purification --- p.63 / Chapter 2.2.5.1 --- Affinity Chromatography of Recombinant Protein --- p.63 / Chapter 2.2.5.2 --- Dialysis of Eluted Recombinant Protein in PBS --- p.64 / Chapter 2.2.5.3 --- Estimation of Recombinant Protein Concentration --- p.65 / Chapter 2.2.6 --- Demonstrate the Anti-inflammatory Activity of rSj 16 --- p.65 / Chapter 2.2.6.1 --- Thioglycollate Induced Macrophage Recruitment --- p.65 / Chapter 2.2.6.2 --- Cytospin and Hemacolor Staining of PECs --- p.66 / Chapter 2.2.6.3 --- FACS Analysis of PECs --- p.67 / Chapter 2.2.6.4 --- Isolation of total RNA by TRIZOL Reagent --- p.67 / Chapter 2.2.7 --- Immunogenicity and Antigenicity of rSjl6 --- p.68 / Chapter 2.2.7.1 --- Western Blot of rSjl6 with Schistosoma japonicum infected rabbit serum --- p.69 / Chapter 2.2.7.2 --- Preparation of Anti-Sj 16 Serum --- p.69 / Chapter 2.2.7.3 --- Western Blot of rSjl6 with immunized mice serum --- p.70 / Chapter 2.2.8 --- FACS analysis of MHC (I) Expression --- p.71 / Chapter 2.2.9 --- Anti-proliferative Assay using BrdU Kit --- p.72 / Chapter Chapter Three : --- Results --- p.73 / Chapter 3.1 --- Amplification of Sj 16 cDNA from Schistosoma japonicum Cercariae total RNA --- p.73 / Chapter 3.2 --- Construction of pBluescript II SK(-) / Sjl6 --- p.75 / Chapter 3.3 --- Analysis of Sj 16 Nucleotide and Amino Acid Sequence --- p.78 / Chapter 3.3.1 --- Blastn Search Analysis --- p.80 / Chapter 3.3.2 --- Blastx Search Analysis --- p.82 / Chapter 3.3.3 --- Structural Analysis --- p.84 / Chapter 3.4 --- Subcloning of Sjl6 cDNA into pET30a+ and pSecTag2B Expression Vector --- p.88 / Chapter 3.5 --- Expression of the rSj 16 --- p.92 / Chapter 3.5.1 --- Animal Cell Expression --- p.92 / Chapter 3.5.1.1 --- Analysis of mRNA Transcript by RT-PCR --- p.93 / Chapter 3.5.1.2 --- Western Blot of Condition Medium --- p.95 / Chapter 3.5.2 --- Bacterial Cell Expression --- p.97 / Chapter 3.5.2.1 --- Optimization of rSjl6 Expression --- p.97 / Chapter 3.5.2.2 --- Estimation of rSjl6 Concentration --- p.98 / Chapter 3.5.2.3 --- Solubility of rSj16 --- p.99 / Chapter 3.5.2.4 --- Western Blot Analysis of rSjl6 --- p.100 / Chapter 3.6 --- Purification of Recombinant Protein --- p.101 / Chapter 3.6.1 --- Purification of rSj16 --- p.101 / Chapter 3.6.2 --- Purification of rSjCa8 --- p.104 / Chapter 3.7 --- Anti-inflammatory Activity of rSj 16 --- p.107 / Chapter 3.7.1 --- Analysis of PECs in Thioglycollate Induced Inflammation --- p.107 / Chapter 3.7.2 --- Hemacolor Staining of PECs --- p.110 / Chapter 3.7.3 --- FACS Analysis of PECs --- p.110 / Chapter 3.7.4 --- RT-PCR of RNA Isolated from PECs --- p.115 / Chapter 3.8 --- Immunogenicity and Antigenicity of rSjl6 --- p.117 / Chapter 3.8.1 --- Immunogenicity of rSj 16 --- p.117 / Chapter 3.8.2 --- Antigenicity of rSj16 --- p.117 / Chapter 3.9 --- Inhibitory Effect of rSj 16 on rMuIFN-a4 Induced Up-regulation of MHC(I) Expression --- p.120 / Chapter 3.9.1 --- Time Course of rMuIFN-α4 Induced Up-regulation of MHC(I) Expression --- p.120 / Chapter 3.9.2 --- Inhibitory Effect of rSjl6 on rMuIFN-α4 Induced MHC (I) Up-regulation --- p.120 / Chapter 3.9.3 --- "Anti-proliferation Effect of rMuIFN-a4, rSj 16 and rSjCa 8" --- p.124 / Chapter 3.9.4 --- Effect of Signal Transduction Inhibitors on rMuIFN-a4 Induced MHC (I) Up-regulation --- p.126 / Chapter Chapter Four : --- Discussion and Conclusion --- p.129 / Chapter 4.1 --- Discussion --- p.129 / Chapter 4.1.1 --- Overview --- p.129 / Chapter 4.1.2 --- Molecular and Structural Analysis of rSj 16 --- p.130 / Chapter 4.1.3 --- Relationship between Sml6 and Sjl6 --- p.131 / Chapter 4.1.4 --- Anti-inflammatory Activity of rSj 16 --- p.132 / Chapter 4.1.5 --- Immunogenicity and Antigenicity of rSjl6 --- p.137 / Chapter 4.1.6 --- Inhibitory Effect of rSjl6 on rMuIFN-a4 Induced Up-regulation of MHC (I) Expression --- p.138 / Chapter 4.1.7 --- Relation between Sj 16 and the Innate Immune System --- p.139 / Chapter 4.1.8 --- Further Study and Significance --- p.140 / Chapter 4.2 --- Conclusion --- p.141 / References --- p.142

Inauguraldissertation zur Erlangung der Würde einer Doktorin der Philosophie, vorgelegt der Philosophie-Naturwissenschaftlichen Fakultät der Universität Basel. / Literaturverz.

No description available.

INTRODUÇÃO: Existem várias doenças que evoluem com hipertensão pulmonar (HP), entre elas a Hipertensão Arterial Pulmonar Idiopática (HAPI) e a Esquistossomose. Acredita-se que um dos principais fatores desencadeantes da HP esteja relacionado com a disfunção endotelial. OBJETIVOS: 1. Avaliar a disfunção endotelial de pacientes com HAPI e esquistossomóticos com e sem HAP usando os marcadores plasmáticos Endotelina-1, Selectina E, VEGF, PDGFAB e PDGF-BB; 2.Avaliar se pacientes com HAP associada à esquistossomose possuem o mesmo grau de disfunção endotelial que pacientes com esquistossomose sem HAP. METODOLOGIA: Foram formados 4 grupos distintos: Controle (n=13), HAPI (n=11), pacientes com esquistossomose e HP (ESQ+HP) (n=13) e pacientes com esquistossomose sem HP (ESQ)(n=13). Os pacientes foram submetidos a avaliação clínica (caracterizados quanto a gravidade), funcional (realizaram ecocardiograma com medida de pressão sistólica de ventrículo direito, ultrassonografia abdominal quando indicada e exames para excluir outras doenças) e laboratorial (entre eles, contagem de leucócitos, plaquetas e dosagem de BNP). A avaliação hemodinâmica foi realizada nos pacientes com HP. Para a análise da disfunção endotelial, foram coletados 40 mL de sangue de todos os indivíduos para a dosagem de Endotelina-1, Selectina E, VEGF, PDGF-AB e PDGF-BB. RESULTADOS: Observou-se que os grupos não se diferiram quanto a idade, houve um predomínio do sexo feminino e os grupos controle e ESQ apresentaram valores de PSVD menores do que os grupos com HP (controles: 23,4±4,6, ESQ: 29,5±8,5, HAPI: 79,8±26,4 e ESQ+HP: 75,2±15,3 mmHg). As medidas hemodinâmicas foram semelhantes em ambos os grupos com HAP. Quanto aos marcadores da função endotelial, o grupo controle apresentou valores séricos de PDGF-BB mais aumentados (8,9±4,8x 103 pg/mL, p<0,001) que os grupos HAPI, ESQ+HP, ESQ (3,7±2,1; 5,2±3 ; 2,4±1,7 x 103 pg/mL, respectivamente). O grupo HAPI apresentou valores mais elevados de Selectina E (61,5±24,2 x 103 pg/mL) que os grupos controle, ESQ+HP e ESQ (14,5±12,2; 23,9±15,3; 21,4±18 x 103 pg/mL, respectivamente, p=0,005). Os valores séricos de PDGF-AB do grupo controle foram mais elevados que no grupo ESQ (p=0,006). Não foram encontradas diferenças significantes nos valores séricos de Endotelina-1 entre os grupos (p=0,281). Em relação ao VEGF, os pacientes com HAPI apresentaram valores séricos similares ao grupo ESQ+HP e mais elevados que o grupo controle e ESQ (p=0,002). O ponto de corte da dosagem da selectina E (43.806 pg/mL) para diferenciar pacientes com HAPI dos pacientes com ESQ+HP apresentou uma sensibilidade de 91% e a especificidade de 89%. O PDGF-BB apresentou uma boa acurácia para distinguir o grupo controle dos demais, com uma sensibilidade de 77% e uma especificidade de 83%. Além disso, a Selectina E apresentou uma forte correlação com o níveis séricos de BNP (r=0,74, p=0,006). O número de leucócitos e de plaquetas foram diferentes entre os três grupos do estudo. Pacientes com HAPI tinham maior número de leucócitos e plaquetas quando comparados com esquistossomóticos. CONCLUSÕES: 1.Pacientes com HAPI apresentaram valores séricos mais elevados de Selectina E do que pacientes com esquistossomose e controles; 2.Pacientes portadores de esquistossomose com e sem HP apresentaram os mesmos valores séricos dos marcadores de disfunção endotelial / INTRODUCTION: There are several diseases that cause Pulmonary hypertension (PH), such as Idiopathic Pulmonary Arterial Hypertension and Schistosomiasis. The mechanisms that lead to PH are thought to be related to endothelial dysfunction. OBJECTIVES: To evaluate endothelial dysfunction, using plasma markers such as Endothelin-1(ET-1), E-Selectin, VEGF, PDGF-AB and -BB, in patients with idiopathic pulmonary arterial hypertension (IPAH) and schistosomiasis patients with or without PH; and to evaluate if schistosomiasis groups have endothelial dysfunction in the same degree. METHODOLOGY: Patients were divided in 4 different groups: Patients with IPAH (n=11), Patients with PH associated to Schistosomiasis (SchPH)(n=13), Patients with Schistosomiasis without PH (Sch)(n=13) and Controls(n=13). PAH patients were classified according to severity. All groups were submitted to echocardiography and right ventricule systolic pressure(RVSP) was measured. Abdominal ultrassonography was used to rule in or rule out schistosomiasis diagnosis. PH patients went through haemodynamics evaluation and all patients had laboratorial assessment (leucocytes and platelet count and BNP levels) Soluble adhesion molecules such as E-Selectin, VEGF, PDGF-AB, PDGF-BB e ET-1 were determined by ELISA. Leucocytes and platelet counts as well as BNP levels were also evaluated. Results: Subjects did not differ according to age and there was a higher proportion of female patients. Controls and Sch subjects had lower RVSP compared to PH groups (Sch: 23.4±4.6, controls: 29.5±8.5, IPAH: 79.8±26.4 and Sch+HP: 75.2±15.3 mmHg). Haemodynamics data did not differ in PH patients. In IPAH group, E-selectin was elevated (61.5±24,2x103pg/mL) compared to controls, Sch+HP and Sch (14.5±12.2; 23.9±15.3; 21.4±18 x103pg/mL, respectively, p=0,005). PDGF-BB was decreased in IPAH, Sch+HP, Sch (3.7±2.1; 5.2±3; 2.4±1.7x103pg/mL, respectively) compared to controls (8.9±4.8x 103 pg/mL, p<0.001). PDGF-AB was elevated in controls (25.6±8.6x103pg/mL) when compared to Sch (11.4±8.6 x103pg/mL)(p=0.006). There were no differences in ET-1 levels within groups. In relation to VEGF, IPAH group had higher levels compared to controls and Sch (96,6±68,2, 38,4±28, 37,±19,2 pg/mL, respectively) (p=0,002). Based on ROC curve, E-selectin cutoff value of 43.806 pg/mL showed a sensitivity of 91% and a specificity of 89% to distinguish IPAH patients from other groups and PDGF-BB had a good accuracy to differentiate controls with a sensitivity of 77% and a specificity of 83%. Furthermore, E-selectin had a strong correlation with BNP levels (r=0,74, p=0,006). The number of leucocytes and platelets were different within groups. IPAH patients had the highest, and Sch group had the lowest blood cells and platelets count. Conclusions: 1. IPAH patients had higher levels of serum E-selectin and VEGF and controls had higher levels of PDGF-BB and AB; 2. Schistosomiasis patients with or without PH had the same levels of endothelial dysfunction serum markers

Schistosomiasis is a water-borne parasitic disease of great public health importance mainly in sub-Saharan African countries. The majority of current control programmes use the antihelminthic drug praziquantel to reduce disease burden in endemic areas. Praziquantel treatment has been reported to accelerate the development of protective immunity against re-infection that otherwise takes years to develop. To date, there is no licensed vaccine for schistosomiasis in humans but an attenuated schistosome parasite vaccine has been tested in animal models. Employing systematic review and meta-analysis approaches, my PhD research has four main objectives relating to attenuated schistosome vaccine and praziquantel treatment: 1) to identify predictors that determine protection levels after treatment with attenuated Schistosoma mansoni vaccines in the mouse model, 2) to quantify the influence of host and schistosome parasite species on attenuated parasite vaccine efficacy, 3) to explore the direction of change (increase/decrease) in schistosome parasite-specific antibody isotypes after praziquantel treatment in humans, 4) to identify predictors of praziquantel efficacy in humans. My analyses revealed three factors that have an influence on the protection levels provided by attenuated schistosome parasite vaccines: increasing numbers of immunizing parasites had a positive effect on the levels of protection whereas increasing the radiation dose and the time to challenge infection had negative effects. Analyses showed that the attenuated schistosome vaccine has the potential to achieve protection levels as high as 79% after a single dose in mice. Alongside this, baboon studies consistently reported protective effects of attenuated schistosome vaccines against re-infection. These results show there is a high potential for an attenuated schistosome parasite vaccine to be effective in humans. A meta-analysis of the influence of praziquantel treatment on the direction of change in schistosome-specific antibody isotypes was conducted. The analysis revealed considerable variability in the antibodies’ direction of change among populations. The results also demonstrated an increase of anti-worm IgA and IgE in the majority of studies. These antibodies have been reported to have a protective effect against re-infection. The combination of age and infection intensity, and the number of days after treatment were identified as influential predictors for some antibody isotypes, but there was no single predictor that consistently affected all antibody isotypes in the same way. Praziquantel efficacy levels in humans were investigated and the analyses revealed that cure rates for schistosomiasis increase with praziquantel dose, and were affected by the identity of the schistosome parasite species (S. mansoni vs. S. haematobium) and the age of the participants (children: 0-19 years old vs. adults: ≥ 20 years old). There has been no clear efficacy level reduction over the treatment years (1979-2013) suggesting that praziquantel is still effective in the treatment of schistosomiasis despite concerns about possible resistance. The development of a schistosome vaccine will benefit from a closer investigation into the mechanisms through which protection is acquired in attenuated schistosome parasite vaccine studies showing high potential efficacy in animal models. Nevertheless, it will take time to develop a schistosome vaccine for human use. The uptake of the vaccine will be made even more challenging by the lack of adequate infrastructure in schistosomiasis endemic areas. In the meantime, close monitoring of praziquantel efficacy levels is necessary to confirm the effectiveness of schistosomiasis control in endemic areas.

O presente trabalho é uma formulação teórica que permite estudar num modelo estocástico, a influência dos erros de classificação na mensuração da prevalência da esquistossomose mansônica. Os erros de classificação são desagregados e identificados como: falhas de leitura por parte do examinador ou preparo inadequado da lâmina; contingências biológicas que possibilitam o aparecimento de ovos não viáveis e a eliminação de ovos contínua por parte dos indivíduos. É apresentada uma solução geral para o problema, bem como soluções para os casos em que se conhece a distribuição de probabilidades do número de ovos de S.mansoni. Uma solução aproximada e independente da forma e dependente dos dois primeiros momentos da distribuição do número de ovos é sugerida. A influência dos erros de classificação pode quantitativamente ser apreciada, através de um conjunto de tabelas elaboradas com diversos valores dos parâmetros intervenientes no problema. / The present paper is a theoretical approach which will, allow studying the influence - in a stochastic model - of errors in classifying the measurement of the prevalence of Schistosomiasis mansoni. The misclassification errors considered are due to: (A) failure of the examiner in either (1) reading or (2) poor technique. (B) biological contingences which will allow for the appearence of (1) sterile eggs, or (2) discontinuity in the elimination of eggs by the carriers. An exact general solution of the problem is presented, as well as solutions for the particular cases in which the probability distribution of S.mansoni eggs counts in known. An approximate solution is suggested, which is independent from the way in which the number of eggs is distributed, but depends upon the first two moments of the probability distribution of the eggs counts. The influence of misclassification errors can be judged in a quantitative way, by means of a set of tables mande up for the different parametric values of the problem.

INTRODUÇÃO: Existem várias doenças que evoluem com hipertensão pulmonar (HP), entre elas a Hipertensão Arterial Pulmonar Idiopática (HAPI) e a Esquistossomose. Acredita-se que um dos principais fatores desencadeantes da HP esteja relacionado com a disfunção endotelial. OBJETIVOS: 1. Avaliar a disfunção endotelial de pacientes com HAPI e esquistossomóticos com e sem HAP usando os marcadores plasmáticos Endotelina-1, Selectina E, VEGF, PDGFAB e PDGF-BB; 2.Avaliar se pacientes com HAP associada à esquistossomose possuem o mesmo grau de disfunção endotelial que pacientes com esquistossomose sem HAP. METODOLOGIA: Foram formados 4 grupos distintos: Controle (n=13), HAPI (n=11), pacientes com esquistossomose e HP (ESQ+HP) (n=13) e pacientes com esquistossomose sem HP (ESQ)(n=13). Os pacientes foram submetidos a avaliação clínica (caracterizados quanto a gravidade), funcional (realizaram ecocardiograma com medida de pressão sistólica de ventrículo direito, ultrassonografia abdominal quando indicada e exames para excluir outras doenças) e laboratorial (entre eles, contagem de leucócitos, plaquetas e dosagem de BNP). A avaliação hemodinâmica foi realizada nos pacientes com HP. Para a análise da disfunção endotelial, foram coletados 40 mL de sangue de todos os indivíduos para a dosagem de Endotelina-1, Selectina E, VEGF, PDGF-AB e PDGF-BB. RESULTADOS: Observou-se que os grupos não se diferiram quanto a idade, houve um predomínio do sexo feminino e os grupos controle e ESQ apresentaram valores de PSVD menores do que os grupos com HP (controles: 23,4±4,6, ESQ: 29,5±8,5, HAPI: 79,8±26,4 e ESQ+HP: 75,2±15,3 mmHg). As medidas hemodinâmicas foram semelhantes em ambos os grupos com HAP. Quanto aos marcadores da função endotelial, o grupo controle apresentou valores séricos de PDGF-BB mais aumentados (8,9±4,8x 103 pg/mL, p<0,001) que os grupos HAPI, ESQ+HP, ESQ (3,7±2,1; 5,2±3 ; 2,4±1,7 x 103 pg/mL, respectivamente). O grupo HAPI apresentou valores mais elevados de Selectina E (61,5±24,2 x 103 pg/mL) que os grupos controle, ESQ+HP e ESQ (14,5±12,2; 23,9±15,3; 21,4±18 x 103 pg/mL, respectivamente, p=0,005). Os valores séricos de PDGF-AB do grupo controle foram mais elevados que no grupo ESQ (p=0,006). Não foram encontradas diferenças significantes nos valores séricos de Endotelina-1 entre os grupos (p=0,281). Em relação ao VEGF, os pacientes com HAPI apresentaram valores séricos similares ao grupo ESQ+HP e mais elevados que o grupo controle e ESQ (p=0,002). O ponto de corte da dosagem da selectina E (43.806 pg/mL) para diferenciar pacientes com HAPI dos pacientes com ESQ+HP apresentou uma sensibilidade de 91% e a especificidade de 89%. O PDGF-BB apresentou uma boa acurácia para distinguir o grupo controle dos demais, com uma sensibilidade de 77% e uma especificidade de 83%. Além disso, a Selectina E apresentou uma forte correlação com o níveis séricos de BNP (r=0,74, p=0,006). O número de leucócitos e de plaquetas foram diferentes entre os três grupos do estudo. Pacientes com HAPI tinham maior número de leucócitos e plaquetas quando comparados com esquistossomóticos. CONCLUSÕES: 1.Pacientes com HAPI apresentaram valores séricos mais elevados de Selectina E do que pacientes com esquistossomose e controles; 2.Pacientes portadores de esquistossomose com e sem HP apresentaram os mesmos valores séricos dos marcadores de disfunção endotelial / INTRODUCTION: There are several diseases that cause Pulmonary hypertension (PH), such as Idiopathic Pulmonary Arterial Hypertension and Schistosomiasis. The mechanisms that lead to PH are thought to be related to endothelial dysfunction. OBJECTIVES: To evaluate endothelial dysfunction, using plasma markers such as Endothelin-1(ET-1), E-Selectin, VEGF, PDGF-AB and -BB, in patients with idiopathic pulmonary arterial hypertension (IPAH) and schistosomiasis patients with or without PH; and to evaluate if schistosomiasis groups have endothelial dysfunction in the same degree. METHODOLOGY: Patients were divided in 4 different groups: Patients with IPAH (n=11), Patients with PH associated to Schistosomiasis (SchPH)(n=13), Patients with Schistosomiasis without PH (Sch)(n=13) and Controls(n=13). PAH patients were classified according to severity. All groups were submitted to echocardiography and right ventricule systolic pressure(RVSP) was measured. Abdominal ultrassonography was used to rule in or rule out schistosomiasis diagnosis. PH patients went through haemodynamics evaluation and all patients had laboratorial assessment (leucocytes and platelet count and BNP levels) Soluble adhesion molecules such as E-Selectin, VEGF, PDGF-AB, PDGF-BB e ET-1 were determined by ELISA. Leucocytes and platelet counts as well as BNP levels were also evaluated. Results: Subjects did not differ according to age and there was a higher proportion of female patients. Controls and Sch subjects had lower RVSP compared to PH groups (Sch: 23.4±4.6, controls: 29.5±8.5, IPAH: 79.8±26.4 and Sch+HP: 75.2±15.3 mmHg). Haemodynamics data did not differ in PH patients. In IPAH group, E-selectin was elevated (61.5±24,2x103pg/mL) compared to controls, Sch+HP and Sch (14.5±12.2; 23.9±15.3; 21.4±18 x103pg/mL, respectively, p=0,005). PDGF-BB was decreased in IPAH, Sch+HP, Sch (3.7±2.1; 5.2±3; 2.4±1.7x103pg/mL, respectively) compared to controls (8.9±4.8x 103 pg/mL, p<0.001). PDGF-AB was elevated in controls (25.6±8.6x103pg/mL) when compared to Sch (11.4±8.6 x103pg/mL)(p=0.006). There were no differences in ET-1 levels within groups. In relation to VEGF, IPAH group had higher levels compared to controls and Sch (96,6±68,2, 38,4±28, 37,±19,2 pg/mL, respectively) (p=0,002). Based on ROC curve, E-selectin cutoff value of 43.806 pg/mL showed a sensitivity of 91% and a specificity of 89% to distinguish IPAH patients from other groups and PDGF-BB had a good accuracy to differentiate controls with a sensitivity of 77% and a specificity of 83%. Furthermore, E-selectin had a strong correlation with BNP levels (r=0,74, p=0,006). The number of leucocytes and platelets were different within groups. IPAH patients had the highest, and Sch group had the lowest blood cells and platelets count. Conclusions: 1. IPAH patients had higher levels of serum E-selectin and VEGF and controls had higher levels of PDGF-BB and AB; 2. Schistosomiasis patients with or without PH had the same levels of endothelial dysfunction serum markers