几内亚首都科纳克里某校高中生艾滋病相关知识、态度的调查

目的了解几内亚首都科纳克里某校高中生艾滋病相关知识、态度的现状。方法2011年11月,采用横断面调查方法,用自制问卷调查几内亚首都科纳克里某中学294名高中生的艾滋病相关知识和态度。测量相关知识和态度的得分情况,并比较不同人口学特征学生得分的差异。结果回收有效问卷284份（96.6%）。调查对象年龄范围为15～18岁,其中男生148人,女生136人。艾滋病相关知识总分范围为4～25分（满分26分）,各条目答对率范围为35.9%～84.9%,只有78.2%的学生知识得分超过13分;被调查学生艾滋病相关态度总分范围为0～8分（满分10分）,各条目态度积极率范围为9.5%～90.5%,仅有27.1%的学生态度较积极;不同性别、年龄和城乡的学生之间知识及态度总分差异无统计学意义。结论几内亚高中生艾滋病知识面狭窄现象较明显,存在较消极态度,需大力加强艾滋病的健康教育工作。     

The azygos lobe: an unusual anatomical observation with pathological and surgical implications

The azygos lobe is a rare anomaly in broncho-pulmonary segmentation due to an unusual course of the azygos vein. Its radiological aspects are well known but there are few anatomical reports about its bronchial and vascular components. The authors describe the characteristic features in a particular case of the azygos lobe observed in the right lung after studying a fresh specimen and doing a casting of said specimen. This azygos lobe was in a position medial to the right upper lobe and above the hilum. It had the shape of an egg and was 5 cm high, 4 cm wide and 2 cm thick. The azygos fissure was of a vertical form. The lobe was ventilated by the posterior branch of the apical segmental bronchus (B1a). This latter was accompanied by two apical sub-segmental arteries (A1ai, A1aii) and the apical intersubsegmental vein (V1a). The new findings were that: first, the azygos lobe bronchus supplied a part of the right upper lobe; second, the passage of the azygos vein deformed the bronchus of the right upper lobe, and not that of the azygos lobe. This means that it was the right upper lobe, rather than the azygos lobe that was predisposed to the pathology. So, in excising this type of azygos lobe, particular precautions have to be taken to spare the bronchus of the azygos lobe that supplies the right upper lobe.     

Quantitation of HIV-1 RNA in dried blood spots by the real-time NucliSENS EasyQ HIV-1 assay in Senegal

Measurement of viral load in plasma remains the best marker for the follow-up of antiretroviral therapy. However, its use is limited in developing countries due to the lack of adequate facilities and equipment, and cryopreservation of plasma during storage and transportation. Practical and reliable methods adapted to field conditions for the collection, transportation and accurate measurement of HIV-1 viral load are needed for the optimum use of antiretroviral therapy in resource-limited countries. This study evaluated the use of dried blood spots (DBS) for the real-time quantitation of HIV-1 RNA levels with the NucliSENS EasyQ((R)) HIV-1 assay (bioMérieux, Lyon, France) under field conditions in Senegal (Africa). Dried blood spots and plasma from 41 patients living in suburban Dakar were used for determination of HIV-1 RNA concentrations and stability at 37 degrees C. Analysis was performed at the Dakar University Hospital laboratory. Extraction was done with the bioMérieux NucliSENS((R)) miniMAGtrade mark, and real-time detection was done with the bioMérieux NucliSENS((R)) EasyQ system. HIV-1 RNA concentrations in plasma were compared with concentrations in dried blood spots after 8 and 15 days at 37 degrees C. The study showed a strong concordance in RNA levels between plasma and dried blood spots, which appear to be very stable over time with no apparent degradation observed after 2 weeks at 37 degrees C (mean difference 0.065logIU/ml). These results suggest that the use of dried blood spots in combination with the NucliSENS EasyQ HIV-1 assay is well adapted for HIV-1 RNA level monitoring in centralized laboratories in developing countries.     

RNA versus DNA (NucliSENS EasyQ HIV-1 v1.2 versus Amplicor HIV-1 DNA test v1.5) for early diagnosis of HIV-1 infection in infants in Senegal

The objective of this study was to compare the performance of the NucliSENS EasyQ HIV-1 v1.2 platform (bioMérieux, France) to the Amplicor HIV-1 DNA test v1.5 (Roche Molecular Systems, Switzerland) in detecting HIV-1 infection in infants using venipuncture-derived whole blood in tubes and dried blood spots. A total of 149 dried blood spots and 43 EDTA-anticoagulated peripheral blood samples were collected throughout Dakar and other areas in Senegal from infants and children aged 3 weeks to 24 months who were born to HIV-1-infected mothers. Samples were tested using the NucliSENS and Amplicor technologies. The NucliSENS and Amplicor results were 100% concordant using either EDTA-anticoagulated peripheral blood or dried blood spots. Compared to Amplicor, the sensitivity and specificity of the NucliSENS test were 100%. The NucliSENS EasyQ HIV-1 RNA assay performed as well as the Amplicor HIV-1 DNA test in detecting HIV-1 infection in infants. In addition, this platform can give an indication of the viral load baseline. The NucliSENS EasyQ platform is a good alternative for early infant diagnosis of HIV-1 infection.     

Incidence and determinants of new AIDS-defining illnesses after HAART initiation in a Senegalese cohort

Background  

Although a dramatic decrease in AIDS progression has been observed after Highly Active Anti Retroviral Therapy (HAART) in both low- and high-resource settings, few data support that fact in low-resource settings.     

Evidence for Multiple B- and T-Cell Epitopes in Plasmodium falciparum Liver-Stage Antigen 3

Liver-stage antigen 3 (LSA-3) is a new vaccine candidate that can induce protection against Plasmodium falciparum sporozoite challenge. Using a series of long synthetic peptides (LSP) encompassing most of the 210-kDa LSA-3 protein, a study of the antigenicity of this protein was carried out in 203 inhabitants from the villages of Dielmo (n = 143) and Ndiop (n = 60) in Senegal (the level of malaria transmission differs in these two villages). Lymphocyte responses to each individual LSA-3 peptide were recorded, some at high prevalences (up to 43%). Antibodies were also detected to each of the 20 peptides, many at high prevalence (up to 84% of responders), and were directed to both nonrepeat and repeat regions. Immune responses to LSA-3 were detectable even in individuals of less than 5 years of age and increased with age and hence exposure to malaria, although they were not directly related to the level of malaria transmission. Thus, several valuable T- and B-cell epitopes were characterized all along the LSA-3 protein, supporting the antigenicity of this P. falciparum vaccine candidate. Finally, antibodies specific for peptide LSP10 located in a nonrepeat region of LSA-3 were found significantly associated with a lower risk of malaria attack over 1 year of daily clinical follow-up in children between the ages of 7 and 15 years, but not in older individuals.Preerythrocytic malaria antigens are critical targets of protective immune responses induced by irradiated sporozoites in humans (9, 22). The demonstration of T-cell-mediated protection in mice immunized by this means (10, 16), the acquisition of a significant level of protection against homologous Plasmodium falciparum challenge in human volunteers (22), and the induction by liver-stage antigens of a high level of protection against P. falciparum infection in chimpanzees (19, 31) all point to a major role for preerythrocytic stage antigens as vaccine candidates.Liver-stage antigen 3 (LSA-3) is a novel antigen expressed at the preerythrocytic stages (4). LSA-3 was selected by the differential immune response found between protected and nonprotected volunteers, both similarly immunized with irradiated sporozoites (4, 9). The gene encoding LSA-3 is unusually well-conserved (4), in contrast with many other malaria vaccine candidates (11, 19, 23). More than 10 dominant T-helper (Th), cytotoxic T-lymphocyte, and B-cell epitopes have already been characterized in LSA-3 (20), some of them displaying cross-reactivity with an homologous antigen in Plasmodium yoelii (2). The protective potential of LSA-3 was demonstrated by a series of experiments in chimpanzees and Aotus monkeys challenged with P. falciparum (4, 21) and in mice challenged by P. yoelii following immunization either by recombinant proteins with adjuvant or by formulations without adjuvant, such as recombinant proteins adsorbed on microparticles or lipopeptides in phosphate-buffered saline (PBS) (4), or DNA-based immunization (29). These convergent results stress the potential of LSA-3 as a prime vaccine candidate.We therefore decided to further analyze the antigenicity of LSA-3 and to investigate immune responses to discrete regions of the protein in exposed individuals living in areas where malaria is endemic.T- and B-cell responses were evaluated in subjects living in two villages in Senegal, West Africa, where malaria is endemic, using three small synthetic peptides and a series of 17 overlapping long synthetic peptides (LSP) encompassing most of the LSA-3 protein. In keeping with preliminary results (20), we found a high prevalence of responses to most regions of this preerythrocytic stage antigen in individuals of different age groups. These results bring additional arguments in favor of the potential of the LSA-3 protein for vaccine development.     

Priapism in sickle cell anaemia in Senegal: prevalence, attitudes and knowledge

We interviewed 108 sickle cell anaemia patients aged 5 years older on priapism, and 113 healthy subjects in a control group. They were recruited in the out-patient consultation of the two sickle cell anemia care units of the Fann teaching hospital in Dakar. Ten cases of priapism were identified, all in the group of sickle cell patients (the difference is significant, p = 0.004). Prevalence of priapism was 9.3%. Actuarial probability of having priapism was 8.3% by 10 years of age, and 38.9% +/- 5.7 by 20 years of age. Before the interview, only 10.2% of the sickle cell patients and 8% in the control group knew about priapism, and most of them were unaware of its association with sickle cell disease (75% of sickle cell anaemia patients and 80% of control subjects). This lack of information should be improved by an educational program.     

Ultrastructure of spermiogenesis and spermatozoa of Taenia parvaBaer, 1926 (Cestoda,Cyclophyllidea, Taeniidae), a parasite of the common genet ( Genetta genetta)

We studied the ultrastructure of spermiogenesis and of the mature spermatozoon of Taenia parva, an intestinal cestode of the common genet, Genetta genetta. Spermiogenesis in T. parva is characterized by the growth of the axoneme externally to a cytoplasmic extension. After a slight rotation, the free flagellum fuses with the cytoplasmic extension. This pattern corresponds to type III spermiogenesis according to the scheme proposed by Ba and Marchand. The zone of differentiation lacks both striated roots associated with the centrioles and the intercentriolar body between them. Nevertheless, the flagellar rotation of about 45 degrees is observed in this species. On the other hand, the mature spermatozoon of T. parva, as in other cestodes, is filiform, tapered at both extremities and lacks mitochondria. The presence of a single crest-like body, periaxonemal sheath, and transverse intracytoplasmic walls are also characteristic ultrastructural features. The pattern of spermiogenesis and the ultrastructural organization of the spermatozoon of T. parva are compared with the available data on cyclophyllideans and, in particular, species of the family Taeniidae.     

Comparison of time-resolved and continuous-wave near-infrared techniques for measuring cerebral blood flow in piglets

A primary focus of neurointensive care is monitoring the injured brain to detect harmful events that can impair cerebral blood flow (CBF), resulting in further injury. Since current noninvasive methods used in the clinic can only assess blood flow indirectly, the goal of this research is to develop an optical technique for measuring absolute CBF. A time-resolved near-infrared (TR-NIR) apparatus is built and CBF is determined by a bolus-tracking method using indocyanine green as an intravascular flow tracer. As a first step in the validation of this technique, CBF is measured in newborn piglets to avoid signal contamination from extracerebral tissue. Measurements are acquired under three conditions: normocapnia, hypercapnia, and following carotid occlusion. For comparison, CBF is concurrently measured by a previously developed continuous-wave NIR method. A strong correlation between CBF measurements from the two techniques is revealed with a slope of 0.79±0.06, an intercept of -2.2±2.5 ml∕100 g∕min, and an R2 of 0.810±0.088. Results demonstrate that TR-NIR can measure CBF with reasonable accuracy and is sensitive to flow changes. The discrepancy between the two methods at higher CBF could be caused by differences in depth sensitivities between continuous-wave and time-resolved measurements.