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1.
Ndembi N Takehisa J Zekeng L Kobayashi E Ngansop C Songok EM Kageyama S Takemura T Ido E Hayami M Kaptue L Ichimura H 《Journal of acquired immune deficiency syndromes (1999)》2004,37(5):1641-1650
To monitor the presence of genotypic HIV-1 variants circulating in eastern Cameroon, blood samples from 57 HIV-1-infected individuals attending 3 local health centers in the bordering rural villages with Central African Republic (CAR) were collected and analyzed phylogenetically. Out of the 40 HIV-1 strains with positive polymerase chain reaction (PCR) profile for both gag and env-C2V3,12 (30.0%) had discordant subtype or CRF designation: 2 subtype B/A (gag/env), 1 B/CRF01, 2 B/CRF02, 1 CRF01/CRF01.A, 2 CRF11/CRF01, 1 CRF13/A, 1 CRF13/CRF01, 1 CRF13/CRF11, and 1 G/U (unclassified). Twenty-eight strains (70.0%) had concordant subtypes or CRF designation between gag and env: 27 subtype A and 1 F2. Out of the remaining 17HIV-1 strains negative for PCR with the env-C2V3 primers used, 10 (58.8%) had discordant subtype or CRF, and 7 (41.2%) had concordant one based on gag/pol/env-gp41 analysis. Altogether, a high proportion (22/57, 38.6%) of the isolates were found to be recombinant strains. In addition, an emergence of new forms of HIV-1 strains, such as subtype B/A (gag/env), B/CRF01 and B/CRF02, was identified. The epidemiologic pattern of HIV-1 in eastern Cameroon, relatively low and high prevalence of CRF02 and CRF11, respectively, was more closely related to those of CAR and Chad than that of other regions of Cameroon, where CRF02 is the most predominant HIV-1 strain. These findings strongly suggest that this part of Cameroon is a potential hotspot of HIV-1 recombination, with a likelihood of an active generation of new forms of HIV-1 variants, though epidemiologic significance of new HIV-1 forms is unknown. 相似文献
2.
One group of 5 pigmented rabbits, during a period of 10 weeks, and two groups of 8 albino rabbits, during 16 weeks, showed a fall in aqueous turnover rate and outflow facility of about 30%. A fall in intraocular pressure also occurred of about 10 mm Hg. The biochemical correlative mechanism, systemic and/or local, is conjectural (reduction of "stress"; homeostasis). Empirically a parallel completely untreated control group should accompany any longitudinal study group in order to differentiate these temporal trends from experimental effects. 相似文献
3.
Fabio Casciani Maxwell T. Trudeau Horacio J. Asbun Chad G. Ball Claudio Bassi Stephen W. Behrman Adam C. Berger Mark P. Bloomston Mark P. Callery John D. Christein Massimo Falconi Carlos Fernandez-del Castillo Mary E. Dillhoff Euan J. Dickson Elijah Dixon William E. Fisher Michael G. House Steven J. Hughes John W. Kunstman 《Surgery》2021,169(4):708-720
BackgroundPancreatoduodenectomies at high risk for clinically relevant pancreatic fistula are uncommon, yet intimidating, situations. In such scenarios, the impact of individual surgeon experience on outcomes is poorly understood.MethodsThe fistula risk score was applied to identify high-risk patients (fistula risk score 7–10) from 7,706 pancreatoduodenectomies performed at 18 international institutions (2003–2020). For each case, surgeon pancreatoduodenectomy career volume and years of practice were linked to intraoperative fistula mitigation strategy adoption and outcomes. Consequently, best operative approaches for clinically relevant pancreatic fistula prevention and best performer profiles were identified through multivariable analysis models.ResultsEight hundred and thirty high-risk pancreatoduodenectomies, performed by 64 surgeons, displayed an overall clinically relevant pancreatic fistula rate of 33.7%. Clinically relevant pancreatic fistula rates decreased with escalating surgeon career pancreatoduodenectomy (–49.7%) and career length (–41.2%; both P < .001), as did transfusion and reoperation rates, postoperative morbidity index, and duration of stay. Great experience (≥400 pancreatoduodenectomies performed or ≥21-year-long career) was a significant predictor of clinically relevant pancreatic fistula prevention (odds ratio 0.52, 95% confidence interval 0.35–0.76) and was more often associated with pancreatojejunostomy reconstruction and prophylactic octreotide omission, which were both independently associated with clinically relevant pancreatic fistula reduction. A risk-adjusted performance analysis also correlated with experience. Moreover, minimizing blood loss (≤400 mL) significantly contributed to clinically relevant pancreatic fistula prevention (odds ratio 0.40, 95% confidence interval 0.22–0.74).ConclusionSurgeon experience is a key contributor to achieve better outcomes after high-risk pancreatoduodenectomy. Surgeons can improve their performance in these challenging situations by employing pancreatojejunostomy reconstruction, omitting prophylactic octreotide, and minimizing blood loss. 相似文献
4.
Tizabi Y Overstreet DH Rezvani AH Louis VA Clark E Janowsky DS Kling MA 《Psychopharmacology》1999,142(2):193-199
Epidemiological studies indicate a high incidence of cigarette smoking among depressed individuals. Moreover, individuals
with a history of depression have a much harder time giving up smoking. It has been postulated that smoking may reflect an
attempt at self-medication with nicotine by these individuals. Although some animal and human studies suggest that nicotine
may act as an antidepressant, further verification of this hypothesis and involvement of nicotinic cholinergic system in depressive
symptoms is required. Flinders Sensitive Line (FSL) rats have been proposed as an animal model of depression. These rats,
selectively bred for their hyperresponsiveness to cholinergic stimulation, show an exaggerated immobility in the forced swim
test compared to their control Flinders Resistant Line (FRL) rats. Acute or chronic (14 days) administration of nicotine (0.4 mg/kg
SC) significantly improved the performance of the FSL but not the FRL rats in the swim test. The effects of nicotine on swim
test were dissociable from its effects on locomotor activity. Moreover, the FSL rats had significantly higher [3H]cytisine binding (selective for the α4β2 nicotinic receptor subtype) but not [125I]alpha-bungarotoxin binding (selective for the α7 subtype) in the frontal cortex, striatum, midbrain and colliculi compared to FRL rats. These data strongly implicate the
involvement of central nicotinic receptors in the depressive characteristics of the FSL rats, and suggest that nicotinic agonists
may have therapeutic benefits in depressive disorders.
Received: 9 June 1998/Final version: 6 August 1998 相似文献
5.
Emanuel Noam Kedar Eli Bolotin Elijah M. Smorodinsky Nechama I. Barenholz Yechezkel 《Pharmaceutical research》1996,13(6):861-868
Purpose. To evaluate benefits in tumor localization, availability, and noncancerous organ distribution of doxorubicin (DOX) delivered via small (120 nm) sterically stabilized immunoliposomes targeted against a tumor-associated antigen in fibrosarcoma-bearing mice.
Methods. DOX-loaded liposomes were prepared with (i) specific monoclonal IgG3 antibody (32/2, D-SSIL-32/2); (ii) non-specific IgG3 (D-SSIL-IgG); or (iii) no IgG (D-SSL) on their surface. Equal DOX amounts were injected intravenously via each type of liposome into BALB/c mice carrying experimental lung metastases of a polyoma virus-induced fibrosarcoma (A9 etc 220) expressing a polyoma virus-induced tumor-associated antigen (PAA) on their surface. Metastases occurred mainly in lung. Mice were treated at 3 stages of tumor development (micrometastases, medium-size metastases, and large, necrotic metastases). Performance evaluation was based on time-dependent quantification of DOX and DOX metabolites (DOX-M) in lung tumor, noncancerous organs, and plasma.
Results. (i) DOX delivered via both SSIL retained the prolonged circulation time typical of DOX delivered via D-SSL. (ii) DOX accumulation in noncancerous organs was similar for all preparations. Low levels of DOX-M were obtained for all three preparations in all organs except liver, suggesting a similar processing, (iii) Preparations differed in behavior in lung tumor depending on tumor size and microanatomy. Only at the micrometastases stage were the specifically targeted D-SSIL-32/2 superior to D-SSL and D-SSIL-IgG, delivering 2–4 times more drug into the tumor, (iv) DOX-M level in all three tumor stages was in the following order: D-SSIL-32/2 >> D-SSL >> D-SSIL-IgG, suggesting that DOX delivered as D-SSIL-32/2 is most available to tumor cells.
Conclusions. The advantage of specific targeting of sterically stabilized liposomes is expressed mainly in increasing availability of DOX to tumor cells in a way which is dependent on tumor microanatomy. The impact of this advantage to therapeutic efficacy remains to be determined. 相似文献
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Pediatric HIV remains a significant global health dilemma, especially in resource-constrained nations. As access to ART increases around the world, areas of concern in pediatric HIV treatment include age-appropriate disclosure of HIV status to children and development of adherence habits over time. This review was conducted to synthesize quantitative associations reported between disclosure and adherence among children living with HIV in resource-limited settings. An electronic database search of PubMed, MEDLINE and Cochrane returned 1348 results after removal of duplicates, 14 of which were found to meet inclusion criteria. Review of these reports showed conflicting results regarding the impact of disclosure on adherence, with 5 showing no association, 4 showing a negative impact of disclosure on adherence, and 5 showing positive benefits of disclosure for adherence habits. Thus, there was no clear consensus on the effect, if any, that disclosure has on medication adherence. Longitudinal, prospective research needs to be conducted to evaluate further impacts that disclosure may have on adherence habits over time, and interventions must be structured to link the two processes together in order to maximize health benefit to the child or adolescent. 相似文献
10.
Tixier Emily N. Verheyen Elijah Luo Yuying Grinspan Lauren Tal Du Charles H. Ungaro Ryan C. Walsh Samantha Grinspan Ari M. 《Digestive diseases and sciences》2022,67(3):978-988
Digestive Diseases and Sciences - Severe and fulminant Clostridioides difficile infection (CDI) is associated with significant morbidity and mortality. While fecal microbiota transplantation (FMT)... 相似文献