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991.
Based on pollen analysis, 17 honey samples collected in the Caatinga area from Nova Soure city were classified by botanical origin to identify the most important floral sources. Most of the honey samples were obtained in August and September. A total of 73 pollen types were identified belonging to 30 families, 64 genera and 30 species. The families best represented by their number of pollen types were Mimosaceae (11), Caesalpiniaceae (9), Rubiaceae and Fabaceae (5 each). Predominant pollen types were: Mimosa arenosa in four samples, M. sensitiva and M. tenuiflora in one sample. Pollen from Mimosa ursina was registered for the first time in the pollen spectrum of the Caatinga vegetation. The correspondence analysis showed a similarity among the honey samples based on pollen composition. The high representation of pollen from native species such as Chamaecrista nictitans, C. ramosa, C. swainsonii and Copaifera martii (Caesalpiniaceae); Aeschynomene martii and Zornia sericea (Fabaceae); Herissantia tiubae (Malvaceae); Mimosa arenosa, M. quadrivalvis, M. sensitiva, M. tenuiflora, M. ursina, Piptadenia moniliformis and Plathymenia reticulata (Mimosaceae), and Ziziphus joazeiro (Rhamnaceae) supports the origin of these honeys from Caatinga vegetation.  相似文献   
992.
993.
Myosin V (MyoV) motors have been implicated in the intracellular transport of diverse cargoes including vesicles, organelles, RNA-protein complexes, and regulatory proteins. Here, we have solved the cargo-binding domain (CBD) structures of the three human MyoV paralogs (Va, Vb, and Vc), revealing subtle structural changes that drive functional differentiation and a novel redox mechanism controlling the CBD dimerization process, which is unique for the MyoVc subclass. Moreover, the cargo- and motor-binding sites were structurally assigned, indicating the conservation of residues involved in the recognition of adaptors for peroxisome transport and providing high resolution insights into motor domain inhibition by CBD. These results contribute to understanding the structural requirements for cargo transport, autoinhibition, and regulatory mechanisms in myosin V motors.  相似文献   
994.

Purpose

In recent years, considerable concern has been expressed about the deleterious effects of reactive oxygen species (ROS) on sperm function, because ROS at high levels is potentially detrimental to sperm function and quality. Nitric oxide (NO) is a powerful anti-oxidant present in seminal plasma. The aim of the study was to analyze the distribution of the of endothelial nitric oxide synthase (eNOS) gene (T-786C, G894T, e 4a/b) polymorphisms in idiopathic infertile Brazilian men and evaluate the possible role of these polymorphisms in sperm count.

Methods

A case–control study was performed comprising 208 infertile men [n = 74 with non-obstructive azoospermia and n = 134 with severe oligozoospermia] and 201 fertile men as controls. Genotyping of eNOS polymorphisms was performed by real time (T-786C and G894T) and conventional PCR (4a/b). The results were analyzed statistically and a p-value < 0.05 was considered significant.

Results

According to the sperm count, relatively similar eNOS polymorphism genotypes and allele frequencies were found among the groups. Combined genotypes of the eNOS polymorphisms did not identify a haplotype associated with idiopathic infertility, even when the patients were separated in non-obstructive azoospermia or severe oligozoospermia.

Conclusion

In conclusion, the findings demonstrate that, in Brazilian population studied, genetic variations, T-786C, G894T, and e 4a/b, of the eNOS gene are not associated with male infertility.  相似文献   
995.
Maternal overnutrition during suckling period is associated with increased risk of metabolic disorders in the offspring. We aimed to assess the effect of Vitis vinifera L. grape skin extract (ACH09) on cardiovascular and metabolic disorders in adult male offspring of rats fed a high-fat (HF) diet during lactation. Four groups of female rats were fed: control diet (7% fat), ACH09 (7% fat plus 200 mg kg?1 d?1 ACH09 orally), HF (24% fat), and HF+ACH09 (24% fat plus 200 mg kg?1 d?1 ACH09 orally) during lactation. After weaning, all male offspring were fed a control diet and sacrificed at 90 or 180 days old. Systolic blood pressure was increased in adult offspring of HF-fed dams and ACH09 prevented the hypertension. Increased adiposity, plasma triglyceride, glucose levels and insulin resistance were observed in offspring from both ages, and those changes were reversed by ACH09. Expression of insulin cascade proteins IRS-1, AKT and GLUT4 in the soleus muscle was reduced in the HF group of both ages and increased by ACH09. The plasma oxidative damage assessed by malondialdehyde levels was increased, and nitrite levels decreased in the HF group of both ages, which were reversed by ACH09. In addition, ACH09 restored the decreased plasma and mesenteric arteries antioxidant activities of superoxide dismutase, catalase and glutathione peroxidase in the HF group. In conclusion, the treatment of HF-fed dams during lactation with ACH09 provides protection from later-life hypertension, body weight gain, insulin resistance and oxidative stress. The protective effect ACH09 may involve NO synthesis, antioxidant action and activation of insulin-signaling pathways.  相似文献   
996.
RABL6A (RAB-like 6 isoform A) is a novel protein that was originally identified based on its association with the Alternative Reading Frame (ARF) tumor suppressor. ARF acts through multiple p53-dependent and p53-independent pathways to prevent cancer. How RABL6A functions, to what extent it depends on ARF and p53 activity, and its importance in normal cell biology are entirely unknown. We examined the biological consequences of RABL6A silencing in primary mouse embryo fibroblasts (MEFs) that express or lack ARF, p53 or both proteins. We found that RABL6A depletion caused centrosome amplification, aneuploidy and multinucleation in MEFs regardless of ARF and p53 status. The centrosome amplification in RABL6A depleted p53−/− MEFs resulted from centrosome reduplication via Cdk2-mediated hyperphosphorylation of nucleophosmin (NPM) at threonine-199. Thus, RABL6A prevents centrosome amplification through an ARF/p53-independent mechanism that restricts NPM-T199 phosphorylation. These findings demonstrate an essential role for RABL6A in centrosome regulation and maintenance of chromosome stability in non-transformed cells, key processes that ensure genomic integrity and prevent tumorigenesis.  相似文献   
997.

Background

Due to a rising number of deaths from cancer and other chronic diseases a growing number of people experience complex symptoms and require palliative care towards the end of life. However, population-based data on the number of people receiving palliative care in Europe are scarce. The objective of this study is to examine, in four European countries, the number of people receiving palliative care in the last three months of life and the factors associated with receiving palliative care.

Methods

Cross-national retrospective study. Over two years (2009–2010), GPs belonging to representative epidemiological surveillance networks in Belgium, the Netherlands, Italy, and Spain registered weekly all deaths of patients (≥18 years) in their practices and the care they received in the last three months of life using a standardized form. Sudden deaths were excluded.

Results

We studied 4,466 deaths. GPs perceived to have delivered palliative care to 50% of patients in Belgium, 55% in Italy, 62% in the Netherlands, and 65% in Spain (p<.001). Palliative care specialists attended to 29% of patients in the Netherlands, 39% in Italy, 45% in Spain, and 47% in Belgium (p<.001). Specialist palliative care lasted a median (inter-quartile range) of 15 (23) days in Belgium to 30 (70) days in Italy (p<.001). Cancer patients were more likely than non-cancer patients to receive palliative care in all countries as were younger patients in Italy and Spain with regard to specialist palliative care.

Conclusions

Although palliative care is established in the countries studied, there are considerable differences in its provision. Two potentially underserved groups emerge non-cancer patients in all countries and older people in Italy and Spain. Future research should examine how differences in palliative care use relate to both patient characteristics and existing national health care policies.  相似文献   
998.

Introduction

In recent years, the incidence of sepsis has increased in critically ill HIV/AIDS patients, and the presence of severe sepsis emerged as a major determinant of outcomes in this population. The inflammatory response and deregulated cytokine production play key roles in the pathophysiology of sepsis; however, these mechanisms have not been fully characterized in HIV/AIDS septic patients.

Methods

We conducted a prospective cohort study that included HIV/AIDS and non-HIV patients with septic shock. We measured clinical parameters and biomarkers (C-reactive protein and cytokine levels) on the first day of septic shock and compared these parameters between HIV/AIDS and non-HIV patients.

Results

We included 30 HIV/AIDS septic shock patients and 30 non-HIV septic shock patients. The HIV/AIDS patients presented low CD4 cell counts (72 [7-268] cells/mm3), and 17 (57%) patients were on HAART before hospital admission. Both groups were similar according to the acute severity scores and hospital mortality. The IL-6, IL-10 and G-CSF levels were associated with hospital mortality in the HIV/AIDS septic group; however, the CRP levels and the surrogates of innate immune activation (cytokines) were similar among HIV/AIDS and non-HIV septic patients. Age (odds ratio 1.05, CI 95% 1.02-1.09, p=0.002) and the IL-6 levels (odds ratio 1.00, CI 95% 1.00-1.01, p=0.05) were independent risk factors for hospital mortality.

Conclusions

IL-6, IL-10 and G-CSF are biomarkers that can be used to predict prognosis and outcomes in HIV/AIDS septic patients. Although HIV/AIDS patients are immunocompromised, an innate immune response can be activated in these patients, which is similar to that in the non-HIV septic population. In addition, age and the IL-6 levels are independent risk factors for hospital mortality irrespective of HIV/AIDS disease.  相似文献   
999.
Granuloma formation involves a coordinated interaction between monocytes and macrophages, epithelioid cells, lymphocytes, eosinophils, neutrophils and fibroblasts. It has been established that extracellular communication via cytokines is important for the assembly of granulomas. However, the importance of gap junctions and intercellular communication to granuloma formation and development had never been assessed. Connexins are proteins that form gap junctions, and connexin 43 (Cx43) is present in macrophages, lymphoid cells, myelogenous cells, fibroblasts and others. We analyzed the effect of heterologous deletion of Gja1 (Cx43 gene) on the formation and development of hepatic granulomas induced by Schistosoma mansoni eggs. Heterozygous (Cx43(+/-)) and wild-type (Cx43(+/+)) mice were infected subcutaneously with S. mansoni cercarie and evaluated after 6, 8 and 12 weeks. Granuloma cells express Cx43, as revealed by real-time PCR in isolated granulomas, and by immunohistochemistry. Cx43 expression was reduced in Cx43(+/-) mice, as expected. No differences in the average area of granulomas or number of cells per granuloma were observed between mice of different genotypes. However, granuloma cells from Cx43(+/-) mice displayed a reduced index of the proliferating cell nuclear antigen (PCNA) labeling at 8 and 12 weeks post-infection. Moreover, Cx43(+/-) granulomas unexpectedly presented a higher degree of fibrosis, quantified by morphometric analysis in Sirius Red-stained slides. Our results indicate that the deletion of one allele of the Cx43 gene, and possibly the reduced gap junction intercellular communication capacity (GJIC), may impair the interactions between granuloma cells, reducing their proliferation and increasing their collagen content, thereby modifying the characteristics of S. mansoni granuloma in mice.  相似文献   
1000.
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