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In this paper we addressed the expression of the HIV co-receptors CXCR-4 and CCR-5 in human thymocytes by phenotypic, molecular and functional approaches. Cytofluorimetric analysis disclosed that CXCR-4 was constitutively expressed by freshly isolated thymocytes (~10 000 molecules/cell in about 30% of thymocytes); the receptor was endowed with functional activity, as it mediated polarization, migration and intracellular Ca2+ increase in response to its ligand, SDF-1. On the contrary, CCR-5 expression in freshly isolated thymocytes was significantly lower (<4000 molecules/cell in less than 5% of the cells), and no functional response to CCR-5 agonists could be documented. Northern blot analysis of freshly isolated thymocytes showed high CXCR-4 mRNA levels, whereas the message for CCR-5 was barely detectable. On the other hand, a modest increase in the expression of CCR-5 was associated with in vitro thymocyte stimulation, and CCR-5 density at the cell surface attained CXCR-4 figures in most cases. None the less, no functional response to CCR-5 agonists could be documented in in vitro stimulated thymocytes. In vitro infection of thymocytes by CAT-expressing recombinant HIV bearing the envelope glycoproteins from different isolates showed that T-tropic strains, which use CXCR-4 as a co-receptor, were more efficient in infecting thymocytes than M-tropic strains, which preferentially use CCR-5. Altogether, these data indicate that expression of the major co-receptors involved in infection by M-tropic HIV strains is very poor in human thymocytes, and would suggest that thymocyte infection by M-tropic HIV strains may be a rare event in vivo.  相似文献   
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In light of the global crisis created by the outbreak of the coronavirus and the disease it causes, coronavirus disease 2019, the goal of the study was to detect factors that might enhance people's ability to experience positive psychological change during traumatic events. As such, this study examined the relationship between social participation and posttraumatic growth (PTG) during the coronavirus outbreak and tested the mediating role of hope, social support, and cognitive reappraisal in explaining this relationship. The sample consisted of 275 participants (21.8% male, and 78.2% female, with an average age of 33.42, SD = 13.63), subjected to social-distancing regulations during this period. Results demonstrated a serial mediation model in which social participation predicted PTG directly and indirectly through hope (pathways and agency), social support, and cognitive reappraisal. The importance of social participation in nourishing personal resources and practical implications including the need for prevention programs are discussed.  相似文献   
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Purpose

Does thawing cleavage embryos and culturing them for transfer as blastocysts improve pregnancy and perinatal outcomes compared to transferring thawed blastocysts?

Methods

Retrospective, observational cohort study performed at two assisted reproductive technology centers, 2014 to 2020. A total of 450 patients with 463 thawed embryo transfer cycles were divided into 2 groups according to the embryonic developmental stage at cryopreservation and transfer: 231 thawed blastocysts (day 5 group) and 232 thawed cleavage embryos that were cultured for 2 days and transferred as blastocysts (day 3–5 group). The two groups were compared for demographics, routine parameters of IVF treatment, pregnancy rates, and perinatal outcomes.

Results

Multivariable logistic regression analysis for ongoing pregnancy and delivery demonstrated that the day 3–5 group had a greater likelihood of achieving ongoing pregnancy and delivery compared to the day 5 group (OR 1.58, 95%CI 1.062–2.361, p?=?0.024). Perinatal outcomes were comparable between the three groups.

Conclusion

Our results support culturing post-thaw cleavage embryos for 2 days and transferring them as blastocysts to increase chances of ongoing pregnancy and delivery.

  相似文献   
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Background

Graft pseudoaneurysm (PSA) following pancreatic transplantation (PT) is a rarely reported complication that has significant morbidity and mortality. Few case reports and small series of this complication exist.

Methods

Retrospective review of files of 106 patients who underwent PT at the Tel-Aviv Sourasky Medical center between 1995 and 2010. Accessible asymptomatic patients (n = 35) were referred for graft PSA screening using ultrasound-Doppler.

Results

Eight patients developed graft PSA (8 %). All had early posttransplant sepsis. PSA incidence among patients who had perioperative sepsis is 13 %. Three patients developed early postoperative PSA, presenting as massive abdominal bleeding requiring urgent laparotomy and graft resection. Five patients were diagnosed with late-onset graft PSA between 3 months and 11 years posttransplant: clinical presentations were massive gastrointestinal bleeding (n = 2), acute renal failure (n = 1), and asymptomatic finding on screening ultrasound-Doppler (n = 2, 6 % of screened patients).

Conclusions

PSA following PT occurs in 8 % of patients. Perioperative infection is a risk factor. Early PSAs present as massive intra-abdominal bleeding. PSA may develop years posttransplant, may be asymptomatic, but late rupture is possible and presents as gastrointestinal bleeding. We recommend screening of patients at risk with ultrasound Doppler for early detection and treatment of asymptomatic PSAs.  相似文献   
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International Journal of Geriatic Psychiatry 2009; 24: 90–95 DOI: 10.1002/gps.2110 If has come to our attention that this Research Article was published with an incorrect SUMMARY. We now publish below, the entire SUMMARY as first intended.  相似文献   
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