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61.
A number of studies have demonstrated that adolescent rodents are more sensitive to the rewarding effects of nicotine compared to adults. To help determine the potential brain circuitry involved, we investigated the effect of acute nicotine administration (0.4 or 0.8 mg/kg, s.c.) on the expression of c-fos mRNA in the brains of adolescent (P35) and adult (P67-70) male Wistar rats using in situ hybridization. Nicotine administration increased c-fos mRNA expression in several brain regions, including the central amygdala, locus coeruleus, nucleus accumbens core, paraventricular nucleus of the hypothalamus and lateral septum of adolescent and adult rats. Nicotine increased c-fos mRNA expression more robustly in the bed nucleus of the stria terminalis, nucleus accumbens shell and ventral tegmental area in adolescent rats. The current results suggest that nicotine may have greater activational effects in brain regions associated with reward in adolescent rats and may help to explain the differences between adolescents and adults in behavioral responses to nicotine.  相似文献   
62.
Current HIV/AIDS statistics show that women account for almost 60% of HIV infections in Sub-Saharan Africa. HIV prevention tools such as male and female condoms, abstinence and monogamy are not always feasible options for women due to various socio-economic and cultural factors. Microbicides are products designed to be inserted in the vagina or rectum prior to sex to prevent HIV acquisition.  相似文献   
63.
The clinical and biologic relevance of the t(14;18) and features of germinal center (GC) differentiation in diffuse large B-cell lymphoma (DLBCL) remain controversial. The authors examined the association of t(14;18) with GC-associated markers and clinical features in 44 de novo DLBCLs (22 nodal and 22 primary extranodal). CD10, bcl-2, and bcl-6 were expressed in 50%, 62%, and 54% of cases respectively. There were no significant differences in expression of these markers between nodal and extranodal cases. Coexpression of CD10 and bcl-6 was seen in 12 of 41 cases, and was more frequent in nodal than extranodal DLBCL (9 of 21 vs. 3 of 20; P = 0.05). A CD10+/bcl-6+ phenotype was not significantly associated with bcl-2 expression, stage, complete remission rate, or survival. The t(14;18) was found in 7 of 44 (16%) cases (6 nodal, 1 extranodal; P = 0.09). It was associated with a CD10+/bcl-6+ phenotype (5 of 7 vs. 7 of 27; P = 0.015) and a trend toward more frequent bcl-6 expression (6 of 7 vs. 15 of 34; P = 0.09), but no association with bcl-2 expression, CD10, clinical stage, complete remission, or survival. Among nodal or high-stage (III-IV) DLBCL, cases with the t(14;18) showed a trend toward decreased survival (P = 0.12).  相似文献   
64.
65.
Leukodystrophies are a heterogeneous group of heritable disorders characterized by abnormal brain white matter signal on magnetic resonance imaging (MRI) and primary involvement of the cellular components of myelin. Previous estimates suggest the incidence of leukodystrophies as a whole to be 1 in 7,000 individuals, however the frequency of specific diagnoses relative to others has not been described. Next generation sequencing approaches offer the opportunity to redefine our understanding of the relative frequency of different leukodystrophies. We assessed the relative frequency of all 30 leukodystrophies (associated with 55 genes) in more than 49,000 exomes. We identified a relatively high frequency of disorders previously thought of as very rare, including Aicardi Goutières Syndrome, TUBB4A‐related leukodystrophy, Peroxisomal biogenesis disorders, POLR3‐related Leukodystrophy, Vanishing White Matter, and Pelizaeus‐Merzbacher Disease. Despite the relative frequency of these conditions, carrier‐screening laboratories regularly test only 20 of the 55 leukodystrophy‐related genes, and do not test at all, or test only one or a few, genes for some of the higher frequency disorders. Relative frequency of leukodystrophies previously considered very rare suggests these disorders may benefit from expanded carrier screening.  相似文献   
66.
67.
The morphologic, cytogenetic, and clinical features of 58 patients with transformation of Philadelphia chromosome (Ph1) positive chronic myelogenous leukemia (CML) were evaluated. The patients were divided into two groups on the basis of blood and marrow findings: blast crisis and subacute transformation. The evolution of the leukemic process in 41 patients was classified as blast crisis based on one of three criteria: 30% or more blasts in blood and/or marrow smears, intramedullary focus of blast transformation in a marrow trephine biopsy, or blast transformation in an extramedullary site. The 17 patients with subacute transformation of CML had a deteriorating clinical and hematologic picture but did not manifest any of the criteria for blast crisis. The blood and marrow findings in this group of patients were characterized by several qualitative and quantitative changes, including anemia, thrombocytopenia, decreasing leukocyte count, increasing basophilia, myelofibrosis, dysplastic alterations in hematopoietic cells, and increased blasts which, however, never exceeded 25%. Chromosome abnormalities in addition to the Ph1 were found in 65% of the patients with blast crisis and 86% of the patients with subacute transformation. The 41 patients with blast crisis had a median survival of nine weeks; the 17 with subacute transformation had a median survival of 26 weeks. The shortest median survival for patients with blast crisis, four weeks, occurred in the patients with myeloid blast crisis with chromosome abnormalities in addition to the Ph. The longest median survival, 52 plus weeks, occurred in patients with lymphoid blast crisis with only the Ph1 at transformation.  相似文献   
68.
We describe 9 cases of precursor B-cell lymphoblastic lymphoma (LYL) without evidence of marrow or blood involvement. Four patients had superficial nodal disease, 2 cutaneous involvement, and 1 each ovarian, retroperitoneal, or tonsillar primary tumor. Six patients had limited disease; 3 patients were stage III. Immunophenotyping revealed a terminal deoxynucleotidyl transferase (TdT)-positive, immature B-cell population with variable expression of CD10, CD20, and CD45. All patients are in complete clinical remission (median follow-up, 14 months). A literature review yielded 105 patients with a diagnosis of precursor B-cell LYL based on less than 25% marrow involvement. Of these, 64% were younger than 18 years. Skin, lymph nodes, and bone were the most common sites of disease. Mediastinal involvement was uncommon. TdT, CD19, CD79a, CD10, and HLA-DR were the most frequently expressed antigens, while CD45 and CD20 were expressed in only two thirds of the cases. Cytogenetic analysis showed additional 21q material as a recurring karyotypic abnormality. At a median follow-up of 26 months, 74% of patients were alive; the median survival was 19 months for patients dying of disease. Comparison with precursor B-cell acute lymphoblastic leukemia showed several overlapping features, although distinct differences were identified.  相似文献   
69.
Various forms of private investment are considered necessary for the sustainability of biobanks, yet pose significant challenges to public trust. To manage this tension, it is vital to identify the concerns of relevant stakeholders to ensure effective and acceptable policy and practice. This research examines the aspects of commercialisation that are of most concern to the Australian public (n = 800) and patients who had donated their tissue to two large disease specific (cancer) public biobanks (n = 564). Overall, we found a commercialisation effect (higher support for public relative to private) in relation to funding, research location and access to stored biospecimens. The effect was strongest for research locations and access compared to funding. A latent class analysis revealed the pattern of concern differed, with the majority (34.1%) opposing all aspects of commercialisation, a minority supporting all (15.7%), one quarter (26.8%) opposing some (sharing and selling tissue) but not others (research locations and funding), and a group who were unsure about most aspects but opposed selling tissue (23.5%). Patient donors were found to be more accepting of and unsure about most aspects of commercialisation. Members of the (general) public who were motivated to participate in biobanking were more likely to oppose some aspects while supporting others, while those who indicated they would not donate to a biobank were more likely to oppose all aspects of commercialisation. The results suggest that approaches to policy, engagement and awareness raising need to be tailored for different publics and patient groups to increase participation.Subject terms: Genetics research, Ethics  相似文献   
70.

Background

Dupilumab blocks the shared receptor component for interleukin (IL)-4/IL-13, key drivers of type 2 inflammation. In phase 2b (NCT01854047) and phase 3 LIBERTY ASTHMA QUEST (NCT02414854), add-on dupilumab 200/300 mg every 2 weeks (q2w) reduced severe exacerbations, improved prebronchodilator (pre-BD) forced expiratory volume in 1 second (FEV1) and quality of life measures, and it was generally well tolerated in patients with uncontrolled, persistent (phase 2b), or moderate-to-severe (phase 3) asthma.

Methods

In patients on high-dose inhaled corticosteroids (ICS) with type 2-high asthma (subgroups including baseline blood eosinophils ≥150/300 cells/µL and/or fractional exhaled nitric oxide [FeNO] ≥25 ppb), annualized severe exacerbation rates over the treatment period, changes from baseline in pre-BD FEV1 and asthma control (5-item asthma control questionnaire [ACQ-5]) were analyzed.

Results

In high-dose ICS type 2-high subgroups, dupilumab 200/300 mg q2w vs placebo in the phase 2b (24 weeks) and phase 3 (52 weeks) studies significantly reduced severe exacerbations by 55%-69%/57%-60% (all P<.05) and 53%-69%/48%-66% (all < .001), respectively, except in patients with ≥ 300 eosinophils/µL in phase 2b study (24%/50% (= .52/0.15). Across subgroups, pre-BD FEV1 improved by 0.18-0.22 L/0.19-0.24 L (all < .05) and 0.23-0.36 L/0.15-0.25 L (all < .01) and ACQ-5 scores were reduced by 0.46-0.55/0.47-0.85 (all < .05) and 0.38-0.50/0.24-0.30 (all < .05), respectively, except dupilumab 200 mg q2w in phase 2b in patients with FeNO ≥ 25 ppb (0.41; = .09). Dupilumab was also effective in patients taking medium-dose ICS.

Conclusion

Dupilumab significantly reduced severe exacerbations and improved lung function and asthma control in patients with type 2-high asthma on high-dose ICS at baseline.
  相似文献   
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