Field evaluation of spatial repellency of metofluthrin-impregnated plastic strips against Anopheles gambiae complex in Bagamoyo, coastal Tanzania

Metofluthrin is a newly synthesized pyrethroid possessing high knockdown and lethal activity against mosquitoes. Studies of metofluthrin-impregnated plastic strips have been performed with dengue vectors. This study reports the efficacy of the new prototypes of metofluthrin-impregnated plastic strips against malaria vectors, Anopheles gambiae complex, in the Kongo villages of Bagamoyo district in coastal Tanzania. The study, using 20 houses, half intervention, half control, was conducted for a 124-day period. Pyrethrum spray sheets and Centers for Disease Control and Prevention light traps were used to sample mosquito population indices. The mosquito density indices of the intervention houses were observed to be significantly lower than those of the control houses when pyrethrum spray sheet collection was used (F = 4.61, 1 df, P = 0.038; 98.7% reduction of total mosquito collection compared with that for the controls). These low indices were observed despite the large openings found in Bagamoyo houses, which were predicted to have a considerable negative effect on the spatial repellency of metofluthrin. Based on the present results, the pyrethrum spray sheet collection was the better of the 2 collection methods.     

Adrenal function in patients with active tuberculosis.

Although tuberculosis is a recognised cause of adrenal insufficiency, little is known about adrenal function in patients with active tuberculosis. Ninety Melanesian adults with active tuberculosis (30 pulmonary, 30 miliary, 30 extrapulmonary) had adrenal function assessed prospectively before and three to four weeks after starting antituberculous chemotherapy. Basal serum cortisol concentrations were normal in 55 (61%) and raised in 35 (39%) of the subjects. No patient had a low basal cortisol concentration. After Synacthen stimulation, cortisol responses were normal in 81 (92%) of the patients and subnormal in seven (8%). After antituberculous chemotherapy the response to Synacthen stimulation was normal in all but one patient. It is concluded that adrenal dysfunction is an uncommon problem in patients with active tuberculosis, and that, contrary to recent reports, antituberculous chemotherapy regimens that include rifampicin do not have an adverse effect on adrenal function.     

Spinal intradural neuroepithelial cyst associated with multiple congenital anomalies in a child

A case of spinal intradural neuroepithelial cyst is presented. The patient, who had thoracolumbar hypertrichosis, underwent magnetic resonance imaging which demonstrated a cystic lesion within spinal canal. The cystic lesion was removed surgically. Histological study proved it to be a neuroepithelial cyst. Spinal intradural neuroepithelial cyst associated with other congenital malformations is a rare condition.     

Assessment of quality assurance in HIV testing in health facilities in Lake Victoria zone, Tanzania

Tanzania is currently implementing the antiretroviral treatment programme, and has a target of putting about 400,000 eligible HIV infected individuals on treatment by 2008. This will involve screening a large number of people, which will require non-laboratory personnel to be involved in doing HIV testing. In order to guarantee reliable and quality HIV test results, there is a need to ensure that quality assurance (QA) procedures are followed from specimen collection, testing and reporting of results. In light of the above a survey was conducted to assess QA in HIV testing in health facilities in Lake Victoria zone, Tanzania. A total of 89 health facilities (29 hospitals, 34 health centres, 9 dispensaries and 17 voluntary and counselling testing centres) were surveyed. Only three (10.3%) health facilities reported performing Uniform II ELISA for HIV diagnosis. All other health facilities reported to be using HIV rapid tests Capillus and Determine. Five (5.6%) of health facility laboratories performed CD4 counts. Internal quality control (IQC) were performed in 21 (63.6%) of the hospitals. Kits for HIV testing were reported to be readily available by 54 (60.7%) of the facilities. Only 16 (18%) of the health facilities had standard operating procedures in place. Systems of equipment calibration were reported by 13 (14.6%) of the health facilities. Counselling services were available in all health facilities and all counsellors had received the 6-week mandatory training course. These findings show that most of health facilities in the Lake Victoria zone do not adhere to QA procedures in HIV testing. There is therefore, a need to establish a monitoring system to laboratories performing HIV testing for the purpose of ensuring QA procedures are done. Personnel doing HIV testing should be re-trained at a regular basis to cope with new techniques and ensure QA procedures are followed.     

Microsatellite and mitochondrial genetic differentiation of Anopheles arabiensis (Diptera: Culicidae) from western Kenya, the Great Rift Valley, and coastal Kenya

The population genetic structure of the African malaria vector Anopheles arabiensis from western Kenya, the Great Rift Valley, and coastal Kenya was investigated using 12 microsatellite loci and a partial sequence of mtDNA dehydrogenase gene subunit 5 (ND5). The mean number of alleles and the observed heterozygosity were similar for the mosquito populations from the three regions as revealed by the microsatellite data. A total of 30 polymorphic sites in the ND5 gene defined 39 haplotypes. Six haplotypes were shared among four populations from the three distinct ecological conditions, and they constituted 92% of the total number of individuals sequenced. Mitochondrial haplotype and nucleotide diversity were high. Microsatellite markers within polymorphic inversions revealed a level of genetic differentiation (F(ST) = 0.116) four to seven times higher than markers outside inversions (F(ST) = 0.016) or inside fixed inversions (F(ST) = 0.027). Mitochondrial ND5 gene sequences did not reveal significant genetic differentiation for the same four populations (phi(ST) = -0.008). The contrasts in the level of genetic differentiation between microsatellite markers inside polymorphic inversions, the mitochondrial ND5 gene, and microsatellite markers outside inversions suggest that the level of genetic differentiation in An. arabiensis populations across the Great Rift Valley varies significantly among different areas of the genome. Variations in the degree of genetic differentiation with respect to the chromosomal location of microsatellite markers may result from intrinsic characteristics of the markers, demographic or historic factors affecting these populations, and the possible adaptive significance of chromosomal inversions to climatic conditions.     

Long-term cultures of polarized airway epithelial cells from patients with cystic fibrosis

The poor ability of respiratory epithelial cells to proliferate and differentiate in vitro into a pseudostratified mucociliated epithelium limits the general use of primary airway epithelial cell (AEC) cultures generated from patients with rare diseases, such as cystic fibrosis (CF). Here, we describe a procedure to amplify AEC isolated from nasal polyps and generate long-term cultures of the respiratory epithelium. AEC were seeded onto microporous permeable supports that carried on their undersurface a preformed feeder layer of primary human airway fibroblasts. The use of fibroblast feeder layers strongly stimulated the proliferation of epithelial cells, allowing the expansion of the cell pool with successive passages. AEC at increasing passage were seeded onto supports undercoated with airway fibroblasts and exposed to air. Either freshly isolated or amplified AEC could differentiate into a pseudostratified mucociliated epithelium for at least 10 mo. Thus, CF epithelia cultures showed elevated Na+ transport, drastic hyperabsorption of surface liquid, and absence of cAMP-induced Cl- secretion as compared with non-CF cultures. They were also characterized by thick apical secretion that hampered the movement of cell surface debris by cilia. However, CF respiratory epithelia did not show increased production of mucins or IL-8. The method described here is now routinely used in our laboratory to establish long-term cultures of well differentiated respiratory epithelia from human airway biopsies.     

Seminal plasma prostate-specific antigen level in benign prostatic hyperplasia

INTRODUCTION: We evaluated the role of the seminal plasma PSA level in the prediction of the response to alpha-blocker treatment in patients with benign prostatic hyperplasia. MATERIALS AND METHODS: 18 male patients with lower urinary tract symptoms were enrolled in the study. After their blood was sampled for PSA, ejaculates of all the subjects were obtained. Serum and seminal plasma PSA levels were calculated by Active PSA IRMA kit. Patients were given 4 mg/day doxazosin for a period of 6 weeks, following which their International Prostate Symptom Score (IPSS) evaluation was repeated. The correlation between serum PSA, seminal plasma PSA and PSA density levels and the percentage improvement in IPSS was investigated. RESULTS: The mean serum PSA level, the mean PSA density and the mean seminal PSA level of the patients were 2.7 +/- 1.2 ng/ml, 0.05 +/- 0.02 ng/ml/cm(3) and 0.7 +/- 0.39 g/l, respectively. The percentage improvement in IPSS varied from 26.9 to 53.5%. Serum PSA and serum PSA density were not useful in the prediction of the response to alpha-blocker treatment, but the seminal PSA levels correlated with the percentage improvement in the IPSS (p = 0.017). CONCLUSIONS: Seminal plasma PSA has been found to be a better predictor of the response to alpha-blocker treatment when compared to serum PSA and PSA density.