Summary of Thesis^*

Carréri-Bruno, Glória Cristina - Atividade de culicídeos em área de transição entre o ambiente florestal e o urbano, região do Vale do Ribeira, Estado de São Paulo. São Paulo, 1997. (Dissertação de Mestrado – Faculdade de Saúde Pública da Universidade de São Paulo).

The activity of Culicidae in a transitional area between forested and urban environments, Ribeira Valley region, State of São Paulo, Brazil.

Research on the Culicidae populations of Ribeira Valley is epidemiologically relevant in view of the occurrence of sylvatic cycles of infectious agents, which can cause disease in humans. Aiming at describing the specific composition, monthly distribution, crepuscular and pericrepuscular activity, and epidemiological potential of Culicidae in transitional areas between forested and urban environments, we carried out entomological captures in Parque das Fontes, municipality of Iguape, state of São Paulo, Brazil. Within the period from May 1994 to April 1995, we captured, by bimonthly use of human baits and CDC traps, a total of 8,101 Culicidae specimens, distributed into 13 genera and 75 species of taxonomic groups. The three most abundant species found were, in descending order: Aedes scapularis, Coquillettidia chrysonotum/albifera and Mansonia indubitans. The degree of biodiversity was highest in the forested, decreasing gradually towards the urban environment. Culicidae were captured throughout the year, peaks having been observed in November, March and May. Crepuscular and pericrepuscular activity showed a peak shortly after twilight. Although many species of Culicidae are potential vectors of infectious agents, Aedes scapularis, the most abundant species in all the environments covered in the study, was admittedly the most epidemiologically important, as it has endophagic habits, was captured throughout the year and its competence as a vector of Rocio encephalitis is recognized.

Summary of Thesis^*

CURADO, Izilda - Soroepidemiologia de malária em áreas de baixa endemicidade no Estado de São Paulo. São Paulo, 1995. (Dissertação de Mestrado - Instituto de Ciências Biomédicas da Universidade de São Paulo).

A seroepidemiological malaria survey was conducted in some localities in the Vale do Ribeira (VR), Serra do Mar (SM) and Litoral Norte (LN), State of São Paulo, in an area comprising a radius of 5 to 10 km around homes where autochthonous malaria cases had been reported recently by SUCEN (Superintendência de Controle de Endemias). Several species of monkeys, as well as Anopheles (Kerteszia) cruzii live in these regions, surrounded by Mata Atlântica and every year sporadic malaria cases with mild, atypical symptomatology and extremely low parasitemia are recorded.

The main objectives were: to determine the prevalence of antibodies against the asexual blood stages of P.vivax and anti CS P.vivax, P.vivax VK247, human P.vivax-like/P.simiovale and P.brasilianum/P.malariae antibodies.

Thick and thin blood films, as well as questionnaires comprising epidemiological data, were made of 393 individuals. In only two of these, one asymptomatic and the other with typical symptoms of the flu, a few trophozoites, resembling P.vivax were found. Sera were tested by Indirect Immunofluorescence Assay (IFA) with antigens of asexual forms of P.vivax and Enzyme Linked Immunosorbent Assay (ELISA) with synthetic peptides containing repetitive regions of the circumsporozoite proteins (CS) of "classic" P.vivax (DDAAD)9, P.vivax VK247 (ANGAGNQPG)4, P.malariae/P.brasilianum [(NAAG)4]4 and human P.vivax-like/P.simiovale (APGANQEGGAA)3.

These reactions were standardized and tested for sensitivity, specificity, reproducibility and cut off values. For ELISA cut off, 3 SD were added to mean optical densities of Blood Bank sera.

A surprisingly high positivity rate was obtained in IFA with P.vivax antigen: 54%, 24% and 52% in the 3 localities of VR, 38%, 28% and 7% in localities of SM, these differences being statistically significant, while 32% and 18% were found for LN.

At VR, in Shangrilá and Juquiazinho, there are two distinct populations: permanent residentes (home "caretakers") and home "owners", who go there only on week-ends or holidays. The prevalences of anti-asexual P.vivax antibodies were significantly higher in "caretakers".

IFA with P.malariae antigen were positive with those sera which reacted in ELISA with the CS peptide of this species, which were negative in IFA with P.vivax.

IFA with P.simiovale antigen carried out with all sera reacting in ELISA with this parasites CS peptide, showed that: 1) practically all sera reacting with asexual P.simiovale cross-react with the other two Plasmodium species, usually with a higher titer for the latter; 2) there was no correlation between ELISA positivity with the P.simiovale peptide and the IFA titer with this parasite; 3) tests with other sera also showed cross-reaction between IFA with P.simiovale, P.vivax and P.malariae; 4) practically all IFA negative sera with the two latter parasites were also negative when tested with P.simiovale. These findings make us infer that:

1) possibly P.simiovale, a simian parasite, although circulating in the region, may have resulted in aborted infections in humans, or 2) the asexual form of P.simiovale does not correspond to the human P.vivax-like parasite, since this is still an open question.

The positivity rate of the four peptide anti-CS antibodies was statistically different between closely located areas, with predominance of either one or the other.

1117 anophelines from Pai Mathias (PM) and 1161 from Juquitiba tested for P.malariae/P.brasilianum, P.vivax and P.vivax VK247 infection, resulted in 1 specimen from PM infected by "classic" P.vivax and 1 from Juquitiba by P.vivax VK247. In spite of this low infection rate, 3 employees from SUCEN contracted malaria during mosquito captures in PM.

In view of local conditions (presence of anopheline vectors and monkeys in the woods of these regions) and the high prevalence of anti-Plasmodium antibodies in human sera, as well as the low number of malaria cases and occasional finding of cases with mild symptomatology, we consider the possibility that simian parasites may be circulating in these populations.

Summary of Thesis^*

Montagnini, André Luis - Efeito da cloroquina sobre a pancreatite aguda. Estudo experimental em ratos. São Paulo. 1996. (Tese de Doutoramento - Faculdade de Medicina da Universidade de São Paulo).

Effect of chloroquine on acute pancreatitis. Experimental study in rats.

Acute pancreatitis has a large variety of different clinical pictures. Activation of digestive enzymes inside the zymogen ganule plays an important role and is an early event in acute pancreatitis pathogenesis. Catepsin B, a lysosomal enzyme, is believed to activate trypsinogen to trypsin and depends on an acidic pH inside the zymogen granule. Chloroquine can raise the pH in the zymogen granule. The aim of this study was to evaluate the effect of chloroquine pre administration on acute pancreatitis intensity. One hundred and twenty six male Wistar rats, between 200 and 250 gr., were divided in 4 groups: 1. control (saline administration and no pancreatitis), 2. chloroquine / control (chloroquine administration, 50 mg/kg/ 3 days), 3. pancreatitis (2 doses of 20 µgr/kg of cerulein), 4. chloroquine / pancreatitis (chloroquine pre treatment before pancreatitis induction). All groups were evaluated for serum amylase, water and Evans blue dye content in pancreatic tissue, catepsin B and trypsinogen in pancreatic tissue and histopathological quantification for edema and acinar necrosis. Acridine orange fluorescence was used to quantify zymogen granule pH. Control animals treated with chloroquine showed enlargement of Golgi complex at electron microscope examination, and higher levels of catepsin B in pancreatic tissue. Chroloquine penetrated pancreatitis animals showed significant lower water and dye content and histopathological scores. We concluded that chloroquine pretreatment has a protective effect on cerulein induced pancreatitis in rats.

*

This thesis is available at the Library of the Instituto de Medicina Tropical de São Paulo

Publication Dates

• Publication in this collection
  16 June 1999
• Date of issue
  Jan 1998