Sexual risk behavior, alcohol use, and social media use among secondary school students in informal settlements in Cape Town and Port Elizabeth, South Africa.

South Africa's HIV prevalence among young people remains among the highest in the world. A cross-sectional study was carried out in 2012 to estimate prevalences of sexual risk behavior and hazardous alcohol use (HAU) (via the Alcohol Use Disorder Identification Test) as well as to investigate potential associations between these outcomes and social media use. In all, 4485 students (mean age 15.66 years, SD 1.39) at 46 secondary schools in informal settlements in Cape Town and Port Elizabeth completed mobile-phone-assisted, self-administered baseline questionnaires within a cluster-randomized trial. In all, 312 females (12.5 %) and 468 males (23.5 %) screened positive for HAU (AOR = 1.98, 95 % CI 1.69-2.34). 730 males (39.9 %) and 268 females (11.8 %) reported having had two or more partners in the last year (AOR = 3.46, 95 % CI 2.87-4.16). Among females, having a Facebook account was associated with reported multiple partnerships in the last year (AOR = 1.81, 95 % CI 1.19-2.74), age-disparate sex in the last year (AOR = 1.96, 95 % CI 1.16-3.32) and HAU (AOR = 1.97, 95 % CI 1.41-2.74). Using Mxit-a popular mobile instant messaging application-was associated with higher odds of reported multiple partnerships in the last year among both males (AOR = 1.70, 95 % CI 1.35-2.14) and females (AOR = 1.45, 95 % CI 1.07-1.96) and with HAU among both males (AOR = 1.47, 95 % CI 1.14-1.90) and females (AOR = 1.50, 95 % CI 1.18-1.90). Further longitudinal and qualitative research should explore in more depth the observed links between social media and risk behavior.

Effectiveness of sport-based HIV prevention interventions: a systematic review of the evidence.

Interest in sport as a tool for behavioral HIV prevention has grown substantially in the past decade. With dozens of organisations now using sport-based HIV prevention (SBHP) approaches and upcoming randomized controlled trials in South Africa and Zimbabwe, there is a pressing need to synthesize previous evaluation findings and identify gaps in existing research. A systematic review on the effectiveness of SBHP interventions was carried out, identifying both published and unpublished studies on SBHP interventions that measured effectiveness quantitatively. Study quality was scored using an adapted Newcastle-Ottawa Scale. Random-effects meta-analyses were carried out across studies for effects on six categories of HIV-related outcomes. The review identified 952 publications, 21 of which met inclusion criteria. No randomised controlled trials on SBHP interventions and no studies assessing biological outcomes were identified. Mean study quality score was 5.1 (SD 3.1) out of 20 points. Overall strong evidence was observed for positive effects on HIV-related knowledge (RR = 1.26, 95 % CI = 1.15-1.37), stigma (RR = 1.13, 95 % CI = 1.02-1.24), self-efficacy (RR = 1.22, 95 % CI = 1.02-1.41), reported communication (RR = 1.24, 95 % CI = 1.06-1.41), and reported recent condom use (RR = 1.29, 95 % CI = 1.00-1.59). Generally, the review found encouraging evidence for some short-term effects but relied predominantly on low-quality studies. More rigorous research on SBHP is needed to objectively assess effectiveness. Randomised controlled trials could play an important role in guiding policies, strategies, and funding related to SBHP.

Effectiveness of a sports-based HIV prevention intervention in the Dominican Republic: a quasi-experimental study.

Previous observational and quasi-experimental studies in sub-Saharan Africa have suggested the effectiveness of youth-targeted HIV prevention interventions using sport as an educational tool. No studies have yet assessed the effect of similar programs in the Caribbean. A quasi-experimental trial was conducted to assess the effectiveness of a sports-based intervention in six migrant settlements in the Puerto Plata Province of the Dominican Republic. A total of 397 structured interviews were conducted with 140 adolescents prior to, immediately following, and four months following 10-hour interventions using the Grassroot Soccer curriculum. Interview responses were coded, aggregated into composite scores, and analyzed using logistic regression, adjusting for baseline differences as well as age, sex, community, and descent. At post-intervention, significant differences were observed between groups in HIV-related knowledge (adjOR = 13.02, 95% CI = 8.26, 20.52), reported attitudes (adjOR = 12.01, 95% CI = 7.61, 18.94), and reported communication (adjOR = 3.13, 95% CI = 1.91, 5.12). These differences remained significant at four-month follow-up, though declines in post-intervention knowledge were observed in the Intervention group while gains in knowledge and reported attitudes were observed in the Control group. Results suggest that this sports-based intervention could play a valuable role in HIV prevention efforts in the Caribbean, particularly those targeting early adolescents. Further evaluation of sports-based interventions should include indicators assessing behavioral and biological outcomes, longer-term follow-up, a larger sample, randomization of study participants, and strenuous efforts to minimize loss-to-follow-up.

Zinc and the modulation of Nrf2 in human neuroblastoma cells.

Zinc plays a key role in the modulation of neuronal redox homeostasis. A decreased zinc availability is associated with neuronal NADPH oxidase and nitric oxide synthase activation, deregulation of redox signaling, and impaired glutathione synthesis. The present work tested the hypothesis that zinc is necessary in the neuronal defense response against dopamine (DA)-induced oxidative stress, in particular through heme oxygenase-1 (HO-1) upregulation. DA showed higher cytotoxicity when zinc availability was low. Human IMR-32 neuroblastoma cells responded to high DA concentrations (100 µM) by upregulating HO-1. This upregulation involved Nrf2 translocation to the nucleus, degradation of the Bach-1 repressor, and Nrf2-DNA binding, but it was independent of ERK1/2 activation. DA-mediated induction of HO-1 expression was dependent on the concentration of zinc in the medium. IMR-32 cells incubated in zinc deficient medium showed an impaired response to DA, with lower HO-1 mRNA and protein levels than control DA-challenged cells. This altered HO-1 upregulation was reversed by zinc supplementation. In the presence of DA, Nrf2 nuclear translocation and Bach-1 degradation were lower in zinc deficient cells. The mechanisms involved include: i) impaired Nrf2-tubulin interactions and ii) alterations in the proteasome-mediated degradation of Bach-1 secondary to a decreased ubiquitylation. Results suggest that zinc is crucial in the neuronal response to DA-induced oxidative stress in part through its role in the modulation of the Nrf2-and Bach-1-driven upregulation of HO-1 expression.

[Some problems of regressive evolution].

The concept of morphophysiological regress as one of the main ways to biological progress, as well as its major factors (the sedentary and parasitic modes of life), are discussed. Some notions of regressive evolution are critically reviewed. Special attention is paid to evolutionary transformations of the nervous system, one of the main integrating factors in the body. All theories of evolutionary progress based on sedentary organisms are demonstrated to be untenable. The entire progressive evolution of Metazoa has been related to mobile life. Since regressive trends are common in the evolution, the phylogenetic tree of Metazoa requires serious revision.

West Nile virus outbreak in Israel in 2015: phylogenetic and geographic characterization in humans and mosquitoes.

OBJECTIVES: West Nile Virus (WNV) is endemic in Israel and was responsible for several outbreaks in the past 16 years. The aim of the present study was to investigate the spatial distribution of WNV acute infections from an outbreak that occurred in 2015 in Israel and report the molecular and geographic characterization of WNV isolates from human cases and mosquito pools obtained during this outbreak. METHODS: Using a geographical layer comprising 51 continuous areas of Israel, the number of WNV infection cases per 100 000 people in each area and the locations of WNV-infected mosquitoes in 2015 were analysed. Sequencing and phylogenetic analyses followed by geographic localization were performed on 13 WNV human isolates and 19 WNV-infected mosquito pools. RESULTS: Substantial geographical variation in the prevalence of acute WNV in patients in Israel was found and an overall correlation with WNV-infected mosquitoes. All human patients sequenced were infected only with the Mediterranean subtype of WNV Lineage 1 and resided primarily in the coastal regions in central Israel. In contrast, mosquitoes were infected with both the Mediterranean and Eastern European subtypes of WNV lineage 1; however, only the Mediterranean subtype was found in mosquitoes from the coastal region in central Israel. CONCLUSION: These results demonstrate differential geographic dispersion in Israel of the two WNV subtypes and may also point to a differential pattern of human infections. As a geographical bridge between Europe, Asia and Africa, analysis of WNV circulation in humans and mosquitoes in Israel provides information relevant to WNV infections in Eurasia.

Side-effects of screening.

There has been a 42% increase in the number of mammograms performed outside the national screening programme (operating in Camberwell, southeast London) which was not anticipated in the Forrest Report, a document to the Health Ministers of the U.K. by a working group chaired by Sir Patrick Forrest. The report compiles recommendations on breast screening, using mammography and breast self-examination, to reduce the mortality in women aged 50-64 years. This 42% increase is attributable mainly to referrals from menopause clinics and general practitioners of patients mainly in the screening age group. When we looked at referrals from general practitioners, suspicious mammographic findings were reported in 20% of patients referred with a breast lump, in contrast to only 4% of patients referred with breast pain or nodularity. Better education of both the public and general practitioners, concerning the signs and symptoms of breast cancer, may reduce demands to perform mammographies outside the current national screening programme.

Topoisomerase IIalpha expression in ductal carcinoma in situ of the breast: a preliminary study.

Ductal carcinoma in situ (DCIS) of the breast, a precursor lesion of invasive breast cancer, is a heterogeneous disease in terms of histomorphologic features and biologic behavior. Our aim was to assess the proliferative activity, expressed as topoisomerase IIalpha (Topo IIalpha) immunoreactivity and c-erbB-2 expression in relation to morphologic features and architectural pattern of DCIS. The study included 26 DCIS, which were reclassified according to the recommendations of Consensus Conference. Topo-IIalpha and c-erbB-2 immunoreactivity were detected on paraffin sections. Topo IIalpha was consistently negative in normal ductal epithelium. Topo IIalpha-labeling index (Topo IIalpha-LI) was 0.7+/-0.6% for grade I, 4.3+/-3.9% for grade II, and 13.4+/-8.9 for grade III lesions (P<.01). For mixed nuclear grade DCIS, Topo IIalpha-LI was 6.8+/-4.8. There was no difference in Topo IIalpha-LI between different architectural patterns in low- and intermediate-grade lesions. In high nuclear grade DCIS, there was a progressive increase in Topo IIalpha-LI from solid toward cribriform and comedo-type DCIS. Positive c-erbB-2 immunoreactivity was found in 46% of DCIS, being highest in DCIS with high nuclear grade (78%) and in lesions with extensive necrosis. Topo IIalpha-LI was significantly higher in c-erbB-2-positive lesions (Topo IIalpha-LI- 12.4+/-8.5) as compared with negative lesions (Topo IIalpha-LI- 3.9+/-4.5, P<. 0001). Overexpression of c-erbB-2 and Topo IIalpha is associated with poorly differentiated lesions. Proliferative activity in individual ducts of DCIS depended primarily on the nuclear grade and was independent of architectural patterns of individual ducts in architecturally heterogeneous lesions.

Aberrant crypt foci in human colons: distribution and histomorphologic characteristics.

Aberrant crypt foci (ACF) are one of the earliest putative preneoplastic, and in some cases, neoplastic lesions in human colons. These microscopic lesions, identified on methylene blue-stained mucosa with a low-power-magnification microscope, are thought to be closely related to the earliest steps in multistage colonic tumorigenesis. We investigated the distribution pattern and histomorphological features of ACF in 74 patients with sporadic colorectal cancer. The distribution pattern shows a slightly higher prevalence with older age. The prevalence of the ACF in sigmoid colon was significantly higher in patients with colorectal cancer as compared with patients with benign colonic diseases. Also, significantly more ACF were detected in distal parts of the large bowel (descending, sigmoid colon, and rectum) than in proximal parts. Of 42 microdissected lesions, 12 were dysplastic and 30 were hyperplastic foci. The average size of dysplastic lesions was significantly larger than hyperplastic foci. More apoptotic bodies were found in dysplastic lesions. These lesions also showed an upward expansion of proliferative compartment and higher proliferation indices expressed as proliferating cell nuclear antigen-labeling index. Lymphoid follicles were frequently observed in the base of both hyperplastic and dysplastic foci (40% and 66.6%, respectively). The coincidence of lymphoid follicles was 2.5 to 8 times higher than expected. These features may be related to further progression of selected ACF during colorectal tumorigenesis.

Systemic prophylactic antibiotics in elective biliary surgery.

We tested the effectiveness of prophylactic antibiotics in elective cholecystectomy in 105 patients in a single-blind, controlled randomized trial. Fifty-six patients received prophylactic antibiotics and 49 patients entered the control group. Of the patients who received prophylactic antibiotics, 3.6% had wound infections, v24.5% in the control group. The rate of wound infection in patients with positive bile cultures, diabetes, appendectomies, and choledochotomies was 24.4%, v 3.4% in the group who had cholecystectomies only, with negative bile cultures and no diabetes. We concluded that prophylactic antibiotics are effective in patients with high-risk factors such as diabetes mellitus, exploration of the choledochus, and appendectomy, and in patients with positive bile cultures.

Application of comparative genomic hybridization in search for genetic aberrations in fibroadenomas of the breast.

We applied a comparative genomic hybridization (CGH) technique to paraffin-embedded tissue samples taken from fibroadenomas, benign breast tumors, to detect possible numerical and unbalanced genetic changes. We compared the results to those from previous cytogenetic studies of fibroadenomas. In concurrence with previous cytogenetic studies of fibroadenomas, we detected genetic aberrations in chromosomes 4-6, 8-13, 16, 18, 19, 20, and 22. In addition, with the CGH technique we were able to find two new aberrations, 15q+ and 16p-. Because these aberrations have also been reported to be present in breast cancer, the importance of this finding is yet to be determined.

Oncoprotein coexpression in human aberrant crypt foci and minute polypoid lesions of the large bowel.

BACKGROUND: Genetic aberrations observed in the large bowel during the neoplastic progression have a cumulative effect and are responsible for the propagation of the multistep malignant process. In the present study we evaluated the immunoreactivity of c-fos, ras, bcl-2 and p53 in aberrant crypt foci (ACF) and minute polyps of the large bowel obtained from patients with colorectal cancer. METHODS: ACF and minute polyps were collected from macroscopically normal colonic mucosa. Protein immunoreactivity was detected on parafin sections utilizing the biotin-streptavidin method on 25 hyperplastic, 10 dysplastic ACF, 5 hyperplastic and 10 dysplastic adenomas. RESULTS: 41% of the lesions displayed positive ras immunoreactivity. bcl-2 immunoreactivity was positive in six minute polyps of which five were neoplastic. fos immunoreactivity was detected in five ACF and seven minute polyps, mainly in dysplastic lesions. Two neoplastic polyps were positive for p53 immunoreactivity. Coexpression of two or more oncoproteins was found with increasing frequency in dysplastic versus hyperplastic lesions and in polypoid lesions versus ACF. CONCLUSION: Abnormal expression and coexpression in oncoproteins can be identified in the earliest stages of colorectal tumorigenesis and may contribute to the progression of selected lesions during ACF-adenoma-carcinoma sequence.

Single dose prophylaxis in elective cholecystectomy. A prospective, double-blind randomized study.

We tested the effectiveness of a single dose of prophylactic antibiotic (gentamicin) in elective cholecystectomy in a double-blind, controlled randomized study. All patients recognized preoperatively as being at risk were excluded. The treatment group comprised of 102 patients received a single dose of gentamicin and the 74 patients in the control group received a placebo. Of the patients who received gentamicin, wound infection developed in 4.9 percent versus 13.5 percent in the control group. Among 45 patients who had positive bile cultures, the wound infection rate for those in the treatment group was 14 percent versus 44 percent for those in the control group. Of 17 patients who underwent unexpected exploration of the choledochus, none of those in the treatment group had development of wound infection. The rate of wound infection in the control group was 50 percent. As 30 percent of the patients undergoing elective cholecystectomy were found to have risk factors for the development of wound infection which could not be identified preoperatively, we recommend single dose prophylaxis for all patients undergoing cholecystectomy.

Proliferating cell nuclear antigen as a marker of cell kinetics in aberrant crypt foci, hyperplastic polyps, adenomas, and adenocarcinomas of the human colon.

BACKGROUND: One of the first steps in multistage colonic carcinogenesis is increased cell proliferation and an upward shift of the proliferation zone of colonic crypts. In the present study, progression in cell kinetics was followed up at all sequential stages of colonic carcinogenesis, starting with aberrant crypt foci (ACF), the earliest putative preneoplastic lesions, hyperplastic and dysplastic polyps, and invasive carcinomas. MATERIALS AND METHODS: Colonic tissue and tumor specimens were prospectively obtained from 65 patients treated at our hospital for adenocarcinoma or malignant polyps. For identification of ACFs, dissected mucosal strips obtained from patients with colorectal cancer were stained with 0.1% methylene blue and scanned under dissecting microscope. Paraffin-embedded ACFs and macroscopic lesions were serially sectioned, deparaffinized, and stained with a monoclonal antiproliferating cell nuclear antigen (PCNA) antibody. The PCNA-labelling index (PCNA-LI), expressed as a ratio of positively stained nuclei to total nuclei counted, was calculated separately for basal, middle, and upper colonic crypt compartments. A comparison of the PCNA-LI was made for each compartment in normal mucosa, and hyperplastic and dysplastic lesions. RESULTS: A stepwise increase in the PCNA-LI was observed during neoplastic progression of colonic lesions. The two most important variables of increased cell proliferation, expressed as PCNA-LI per crypt compartment, were the presence of dysplasia and the size of dysplastic lesions. CONCLUSIONS: In colorectal carcinogenesis, hyperproliferation with upward expansion of proliferative compartment is a characteristic feature at all stages of malignant progression.

Frequency of sister-chromatid exchange among greenhouse farmers exposed to pesticides.

Sister-chromatid exchange (SCE) was measured in peripheral lymphocytes of 104 greenhouse farmers exposed to pesticides and 44 unexposed workers. The results of SCEs are expressed in two variables: (a) mean number of SCEs per chromosome and, (b) proportion of high frequency cells (cells with more than eight SCEs). A high correlation was found between these two variables. The adjusted means of both SCEs variables were significantly higher among the farmers compared with the unexposed group (P < 0.01). Adjustment was made for smoking, age, education, and origin. The adjusted means of both SCE variables, were significantly elevated (P < 0.05) among the farmers who prepared and applied more than 70% of the pesticides by themselves compared with those who prepared and applied less than 70% of the pesticides by themselves. Both SCEs variables were also significantly elevated (P < 0.05) among farmers who were involved in more than 7.4 sprays per year compared with those with 7.4 or less sprays per year (P < 0.05). We found a tendency towards elevation of the two variables of SCEs among those who did not use protective measures while preparing the pesticides. Evaluation of the influence of years of exposure on the frequency of SCEs showed that the two variables of SCEs were higher among those farmers who were exposed to pesticides for more than 21 years than among those with less than 21 years of exposure. The variables that had the most influence on the elevation of SCEs were self-preparation of the pesticide mixtures and the number of sprayings per year. Because the farmers used a mixture of almost 24 different chemical classes it was impossible to attribute exposure to a specific pesticide or group of pesticides to single farmers. Our finding of a significant increase of SCEs frequency in peripheral lymphocytes in greenhouse farmers indicates a potential cytogenetic hazard due to pesticides exposure.

Massive gastrointestinal bleeding caused by Dieulafoy's lesion.

Dieulafoy's lesion is an anomaly, difficult to diagnose, consisting of an abnormally dilated submucosal gastric blood vessel that can cause life-threatening gastric hemorrhage. Five patients with Dieulafoy's lesion and massive gastrointestinal bleeding are described. The diagnosis was made by endoscopy in two patients and during operation in the other three. On endoscopy the source of bleeding was localized to the stomach in all patients. This information was important for the operative approach. Conservative treatment failed to prevent rebleeding, and all patients required surgery. In three patients excision of the lesion was performed, and suture only in the other two. The difficulties in diagnosis of the lesion and the surgical options are discussed.

Acute cholecystitis in diabetic patients.

Postoperative outcome and severity of acute cholecystitis in 32 diabetic patients (DM) who underwent urgent cholecystectomy were compared on a case-control basis with 32 nondiabetic age/sex matched controls. There was no difference in incidence of renal and lung diseases or duration of acute symptoms before surgery. Cardiovascular diseases were more often seen in the diabetic group (16/32 in DM, 7/32 in controls, P = 0.03). Bactobilia was more often in diabetics (19 in DM, 11 in controls, p = 0.07). Postoperatively, there was a trend toward higher incidence in overall complication rate. Infectious complications (wound and respiratory infections, hepatic abscess) were higher in DM, although the difference was not statistically significant. One patient in DM group died as a result of multiorgan failure. There was no difference in total and postoperative hospital stay. The severity of acute cholecystitis was greater in diabetics (26 patients with moderate-to-severe cholecystitis in DM group, 18 in control group, P = 0.05). The study indicates that although pathological findings were more severe in DM group, the postoperative course is comparable in diabetics as compared to age and sex matched nondiabetic controls. Our findings justify reconsideration of prophylactic cholecystectomy in asymptomatic diabetic patients.

Cecal diverticulitis presented as a cecal tumor.

Seven patients diagnosed as having acute appendicitis were operated on and a cecal wall mass due to cecal diverticulitis was found. In two patients the mass could not be separated from the cecal wall and right colectomy was performed. In five patients, in whom the mass could be separated from the cecum, conservative operations (three diverticulectomies and two wedge resections) were performed, thus avoiding needless, more extensive surgery.

Subtotal gastrectomy in a teenager with gastroparesis.

Disorders of gastric emptying are rare in healthy infants and children. Delayed gastric emptying is encountered in adults after operations on the stomach, such as vagotomy and partial gastrectomy, and is extremely rare in young patients. The authors report on a 15-year-old patient with gastroparesis after three attempts to repair a congenital diaphragmatic hernia. Medical therapeutic trials consisting of all combinations of diet regimes with various gastrokinetic drugs failed to alleviate the intractable vomiting. All the patient's symptoms resolved after subtotal gastrectomy with gastroduodenostomy (Billroth I).

Pernicious anemia and adenocarcinoma of the stomach in an adolescent: clinical presentation and histopathology.

Primary gastric-carcinoma accounts for only 0.05% of pediatric gastrointestinal malignancies. Although elderly patients who have pernicious anemia are at greater risk of the development of atrophic gastritis and gastric carcinoma, pernicious anemia caused by vitamin B12 deficiency is extremely rare in otherwise healthy adolescents. The authors present a 14.5-year-old boy who had dimorphic anemia caused by vitamin B12 and iron deficiencies in whom atrophic gastritis and gastric carcinoma developed. To the best of our knowledge, this association has not been previously reported in children or adolescents.