Vitellogenin genes are transcribed in Culex quinquefasciatus ovary

BACKGROUND Culex quinquefasciatus, a cosmopolitan, domestic, and highly anthropophilic mosquito, is a vector of pathogenic arboviruses such as West Nile virus and Rift Valley virus, as well as lymphatic filariasis. The current knowledge on its reproductive physiology regarding vitellogenin expression in different tissues is still limited. OBJECTIVES In this study, we analysed the transcriptional profiles of vitellogenin genes in the fat body and ovaries of C. quinquefasciatus females during the first gonotrophic cycle. METHODS C. quinquefasciatus ovaries and/or fat bodies were dissected in different times during the first gonotrophic cycle and total RNA was extracted and used for reverse transcription polymerase chain reaction, quantitative real time-PCR, and in situ hybridisation. FINDINGS We confirmed the classical descriptions of the vitellogenic process in mosquitoes by verifying that vitellogenin genes are transcribed in the fat bodies of C. quinquefasciatus females. Using RNA in situ hybridisation approach, we showed that vitellogenin genes are also transcribed in developing ovaries, specifically by the follicle cells. MAIN CONCLUSIONS This is the first time that vitellogenin transcripts are observed in mosquito ovaries. Studies to determine if Vg transcripts are translated into proteins and their contribution to the reproductive success of the mosquito need to be further investigated.

Occupational infection to Brucella abortus B19 vaccine despite antimicrobial prophylaxis / Infecção ocupacional pela cepa vacinal de Brucella abortus B19 apesar de profilaxia antimicrobiana

ABSTRACT: The authors report the case of a veterinarian who acquired brucellosis infection by accidental exposure to Brucella abortus vaccine (BRUCEL-VET B19) while performing animal vaccination. Antibiotic prophylaxis with doxycycline and rifampin for six weeks was indicated, but rifampin was discontinued after 10 days due to gastrointestinal in-tolerance. Despite prophylaxis, the patient seroconverted after 30 days, but was asymptomatic and did not require additional antibiotic therapy. Post-exposure prophylaxis of Brucella is not free from side effects and asymptomatic seroconversion can occur despite prophylaxis. (AU)

RESUMO: Os autores relatam o caso de um veterinário que adquiriu infecção por brucelose por exposição acidental à vacina Brucellaabortus (BRUCEL-VET B19) durante a vacinação animal. A profilaxia antibiótica com doxiciclina e rifampici-na por seis semanas foi indicada, mas a rifampicina foi descontinuada após 10 dias devido à intolerância gastroin-testinal. A profilaxia pós-exposição de Brucella não está isenta de efeitos colaterais e a soroconversãoassintomática pode ocorrer apesar da profilaxia. (AU)

Culex quinquefasciatus vitellogenesis: morphological and biochemical aspects

The vitellogenic process in Culex quinquefasciatus, which is triggered by a blood meal, involves the synthesis, distribution and storage of the nutrients necessary for embryo development. The fat body of an adult female Cx. quinquefasciatus revealed two cell types: large trophocytes and small, eosinophilic, "oenocyte-like" cells, which show no morphological changes throughout the gonotrophic cycle. Trophocytes, which only begin to synthesise vitellogenin (Vg) 12 h post-blood meal (PBM), undergo a series of morphological changes following engorgement. These changes include the expansion of the rough endoplasmic reticulum (RER) and Golgi complex, which are later destroyed by autophagosomes. At 84 h PBM, trophocytes return to their pre-engorgement morphology. The ovarian follicles of non-blood-fed Cx. quinquefasciatus contain a cluster of eight undifferentiated cells surrounded by follicular epithelium. After engorgement, the oocyte membrane facing the perioocytic space increases its absorptive surface by microvilli development; large amounts of Vg and lipids are stored between 24 and 48 h PBM. Along with yolk storage in the oocyte, follicular cells exhibit the development of RER cisternae and electron-dense granules begin to fill the perioocytic space, possibly giving rise to endochorion. Later in the gonotrophic cycle, electron-dense vesicles, which are possible exochorion precursors, fuse at the apical membrane of follicular cells. This fusion is followed by follicular cell degeneration.

The influence of HCV coinfection on clinical, immunological and virological responses to HAART in HIV-patients

The potential impact of the hepatitis C virus (HCV) on clinical, immunological and virological responses to initial highly active antiretroviral therapy (HAART) of patients infected with human immunodeficiency virus (HIV) is important to evaluate due to the high prevalence of HIV-HCV coinfection. A historical cohort study was conducted among 824 HIV-infected patients starting HAART at a public referral service in Belo Horizonte, Brazil, to assess the impact of HCV seropositivity on appearance of a new AIDS-defining opportunistic illness, AIDS-related death, suppression of viral load, and an increase in CD4-cell count. A total of 76 patients (9.2 percent) had a positive HCV test, 26 of whom (34.2 percent) had a history of intravenous drug use. In multivariate analysis, HCV seropositivity was associated with a smaller CD4-cell recovery (RH=0.68; 95 percent CI [0.49-0.92], but not with progression to a new AIDS-defining opportunistic illness or to AIDS-related death (RH=1.08; 95 percent CI [0.66-1.77]), nor to suppression of HIV-1 viral load (RH=0.81; 95 percent CI [0.56-1.17]) after starting HAART. These results indicate that although associated with a blunted CD4-cell recovery, HCV coinfection did not affect the morbidity or mortality related to AIDS or the virological response to initial HAART.