Knowledge, attitude, and practice (KAP) of HIV prevention and HIV infection risks among Congolese refugees in Tanzania

Little is known about HIV infection risks and risk behaviours of refugees living in resource-scarce post-emergency phase camps in Africa. Our study at Nyarugusu Camp in Tanzania, covering systematically selected refugees (n=1140) and refugees living with HIV/AIDS (PLWHA) (n=182), revealed that the level of HIV risk of systematically selected refugees increased after displacement, particularly regarding the number having transactional sex for money or gifts, while radio broadcast messages are perceived to promote a base of risk awareness within the refugee community. While condoms are yet to be widely used in the camp, some refugees having transactional sex tended to undertake their own health initiatives such as using a condom, under the influence of peer refugee health workers, particularly health information team (HIT) members. Nevertheless, PLWHA were less faithful to one partner and had more non-regular sexual partners than the HIV-negative group. Our study revealed that community-based outreach by refugee health workers is conducive to risk behaviour prevention in the post-emergency camp setting. It is recommended to increase the optimal use of “radio broadcast messages” and “HIT,” which can act as agents to reach out to wider populations, and to strengthen the focus on safer sex education for PLWHA; the aim being to achieve dual risk reduction for both refugees living with and without HIV/AIDS

Evidence for the Involvement of a Src-Related Tyrosine Kinase inXenopusEgg Activation

AbstractRecently, we have purified a Src-related tyrosine kinase, namedXenopustyrosine kinase (Xyk), from oocytes ofXenopus laevisand found that the enzyme is activated within 1 min following fertilization [Satoet al.(1996)J. Biol. Chem.271, 13250–13257]. A concomitant translocation of a part of the activated enzyme from the membrane fraction to the cytosolic fraction was also observed. In the present study, we show that parthenogenetic egg activation by a synthetic RGDS peptide [Y. Iwao and T. Fujimura, T. (1996)Dev. Biol.177, 558–567], an integrin-interacting peptide, but not by electrical shock or the calcium ionophore A23187 causes the kinase activation, tyrosine phosphorylation, and translocation of Xyk. A synthetic tyrosine kinase-specific inhibitor peptide was employed to analyze the importance of the Xyk activity in egg activation. We found that the peptide inhibits the kinase activity of purified Xyk at IC50of 8 μM. Further, egg activation induced by sperm or RGDS peptide but not by A23187 was inhibited by microinjection of the peptide. In the peptide-microinjected eggs, penetration of the sperm nucleus into the egg cytoplasm and meiotic resumption in the egg were blocked. Indirect immunofluorescence study demonstrates that Xyk is exclusively localized to the cortex ofXenopuseggs, indicating that Xyk can function in close proximity to the sperm–egg or RGDS peptide–egg interaction site. Taken together, these data suggest that the tyrosine kinase Xyk plays an important role in the early events ofXenopusegg activation in a manner independent or upstream of calcium signaling

Dynamic 11C-methionine PET analysis has an additional value for differentiating malignant tumors from granulomas : an experimental study using small animal PET

Purpose: We evaluated whether the dynamic profile of 11C-MET may have an additional value in differentiating malignant tumors from granulomas in experimental rat models by small animal PET. Methods: Rhodococcus aurantiacus and allogenic rat C6-glioma cells were inoculated respectively into the right and left calf muscles to generate a rat model bearing both granulomas and tumors (n = 6). Ten days after the inoculations, dynamic 11C-MET PET was performed by small-animal PET up to 120 min after injection of 11C-MET. The next day, after overnight fasting, the rats were injected with 18F-FDG, and dynamic 18F-FDG PET was performed up to 180 min. The time-activity curves, static images, and mean standardized uptake value (SUV) in the lesions were calculated. Results: 11C-MET uptake in the granuloma showed a slow exponential clearance after an initial distribution, while the uptake in the tumor gradually increased with time. The dynamic pattern of 11C-MET uptake in the granuloma was significantly different from that in the tumor (p < 0.001). In the static analysis of 11C-MET, visual assessment and SUV analysis could not differentiate the tumor from the granuloma in all cases, although the mean SUV in the granuloma (1.48 ± 0.09) was significantly lower than that in the tumor (1.72 ± 0.18, p < 0.01). The dynamic patterns, static images, and mean SUVs of 18F-FDG in the granuloma were similar to those in the tumor (p = NS). Conclusions: Dynamic 11C-MET PET has an additional value for differentiating malignant tumors from granulomatous lesions, which deserve further elucidation in clinical settings

Spontaneous clearance of hepatitis C virus after liver transplantation: a report of four cases

End-stage liver disease associated with hepatitis C virus (HCV) infection is the leading indication for liver transplantation. Hepatitis C virus infection recurrence in the graft is common under immunosuppression, leading to an accelerated rate of graft failure. We report the clinical features of four of our patients: three patients presenting with spontaneous hepatitis C virus clearance after liver transplantation and one presenting with transient disappearance of hepatitis C virus postoperatively. The transitional period from surgery to hepatitis C virus clearance was <5 months for all patients. The immunosuppression therapy included tacrolimus, mycophenolate mofetil, and corticosteroids. One ABO-incompatible patient presented spontaneous viral clearance postoperatively for the last 5 years. Two patients had episodes of severe bacterial infection, which resulted in a temporary reduction of immunosuppression. Two patients presented with a transient elevation of transaminase preceding spontaneous hepatitis C virus clearance. These clinical findings suggested that factors including surgical stress, severe bacterial infection, and temporary interruption of immunosuppression were correlated with the reactivation of nonspecific immune responses in the hosts, resulting in spontaneous hepatitis C virus clearance postoperatively

The NF90-NF45 Complex Functions as a Negative Regulator in the MicroRNA Processing Pathway▿ †

The positive regulatory machinery in the microRNA (miRNA) processing pathway is relatively well characterized, but negative regulation of the pathway is largely unknown. Here we show that a complex of nuclear factor 90 (NF90) and NF45 proteins functions as a negative regulator in miRNA biogenesis. Primary miRNA (pri-miRNA) processing into precursor miRNA (pre-miRNA) was inhibited by overexpression of the NF90 and NF45 proteins, and considerable amounts of pri-miRNAs accumulated in cells coexpressing NF90 and NF45. Treatment of cells overexpressing NF90 and NF45 with an RNA polymerase II inhibitor, α-amanitin, did not reduce the amounts of pri-miRNAs, suggesting that the accumulation of pri-miRNAs is not due to transcriptional activation. In addition, the NF90 and NF45 complex was not found to interact with the Microprocessor complex, which is a processing factor of pri-miRNAs, but was found to bind endogenous pri-miRNAs. NF90-NF45 exhibited higher binding activity for pri-let-7a than pri-miR-21. Of note, depletion of NF90 caused a reduction of pri-let-7a and an increase of mature let-7a miRNA, which has a potent antiproliferative activity, and caused growth suppression of transformed cells. These findings suggest that the association of the NF90-NF45 complex with pri-miRNAs impairs access of the Microprocessor complex to the pri-miRNAs, resulting in a reduction of mature miRNA production