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Platelet α-granules release growth factors (GFs) that promote healing and tissue regeneration. Platelet-rich plasma (PRP) is shown to be beneficial in treating alopecia, and however, clinical response can be inconsistent. Due to several fold enrichment of platelets secreting large quantities of GFs following PRP injections, heterogeneity in amounts of GFs secreted by platelets may contribute to inconsistent clinical responses. Herein, we evaluated factors that could potentially contribute to heterogeneous secretion of GFs by platelets. We measured platelet secretion of transforming growth factor beta1 (TGFβ1), platelet-derived growth factor (PDGF-BB), epidermal growth factor (EGF), vascular endothelial growth factor (VEGF) and fibroblast growth factor (FGF2) in aliquots of de-identified PRP samples from female patients undergoing therapy in the hair disease clinic. Although secretion of GFs by platelets was comparable in PRP samples of patients with non-cicatricial and cicatricial alopecia, a Shapiro-Wilk test for normal distribution indicated significant variability across all patient samples. The amount of GF secreted by platelets was comparable when PRP prepared from two FDA-cleared devices with distinct techniques were compared. We provide evidence of platelets secreting heterogeneous amounts of GFs within each sample as high and low secretion of random factors could be simultaneously detected. These results suggest inherent heterogeneity in secretion of GFs by platelets in patient samples that are not influenced by the device used to prepare PRP. Since some GFs could have antagonistic effects on hair growth, a balance between amounts of growth promoting and inhibiting factors may be crucial in determining clinical response to PRP therapy.  相似文献   
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For patients who receive a liver transplant (LTX) for alcoholic liver disease (ALD), investigators are focusing beyond survival to determine specific alcohol use outcomes. Studies suggest the use of alcohol ranges from 8 to 22% for the first post-transplant year with cumulative rates reaching 30 to 40% by 5 years following transplantation. Yet while investigators are interested in determining specific rates of alcohol use and predictors of use, only three studies since 1990 have been prospective. In 1998, we began a prospective study of post-LTX alcohol consumption in ALD recipients using multiple repeated measures of alcohol use. After 5 years of follow-up, we found that 22% had used any alcohol by the first year and 42% had a drink by 5 years. By 5 years, 26% drank at a heavier use (binge) pattern and 20% drank in a frequent pattern. In a univariate model, predictors of alcohol use included pre-transplant length of sobriety, a diagnosis of alcohol dependence, a history of other substance use, and prior alcohol rehabilitation.  相似文献   
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Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a recently described familial cerebrovascular disorder shown to map to chromosome 19q12. Familial hemiplegic migraine has also been shown in some families to map close to the CADASIL locus. The fully developed CADASIL phenotype consists of recurrent strokes developing in the fourth decade, progressing to a pseudobulbar palsy, spastic quadriparesis, and subcortical dementia. In an Irish family 15 members were fully investigated by magnetic resonance scanning; 10 had typical magnetic resonance features of CADASIL. Five members of this family had familial hemiplegic migraine and 4 of these had magnetic resonance evidence of CADASIL. Two other members had migraine with and without aura as a presenting clinical symptom of CADASIL. This disorder has been shown by linkage analysis to map to the CADASIL locus at chromosome 19. The phenotype at presentation of CADASIL in this family was variable and age related and included familial hemiplegic migraine, migraine with and without aura, transient ischemic attacks, strokes, and spinal cord infarction. This family study increases our understanding of the spectrum of clinical manifestations of this underrecognized familial cerebrovascular disorder.  相似文献   
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AIM: Ultraviolet light (UV) is known to cause DNA damage in the epidermis. The damaged DNA is repaired or deleted by apoptosis to prevent the generation of cancer. It has been suggested that a deficient apoptotic mechanism may predispose individuals to skin cancer. Therefore, the response of normal controls and patients with basal cell carcinoma (BCC) to UV irradiation was investigated. METHODS: The buttock skin from normal volunteers and patients with BCC was irradiated using solar simulated radiation (SSR). SSR mimics the effect of natural sunlight. Skin biopsies were excised and examined for p53, p21, and Bax protein expression and for the induction of apoptosis. RESULTS: At 33 hours after UV irradiation, the induction of apoptosis was significantly higher (p = 0.04) in patients with BCC than in normal volunteers (Mann Whitney test). A trend towards higher p21 expression was found at 33 hours in patients with BCC (mean, 18.69 positive cells/field) than in normal volunteers (mean, 9.89), although this difference was not significant (p = 0.05 positive cells/field). CONCLUSION: These results may imply that patients with BCC have enhanced sensitivity to UV irradiation or that there is some defect in the cell arrest or repair pathways, which results in damaged cells been pushed into apoptosis rather than repair.  相似文献   
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Comprehensive genome scans involving many thousands of SNP assays will require significant amounts of genomic DNA from each sample. We report two successful methods for amplifying whole-genomic DNA prior to SNP analysis, multiple displacement amplification, and OmniPlex technology. We determined the coverage of amplification by analyzing a SNP linkage marker set that contained 2320 SNP markers spread across the genome at an average distance of 2.5 cM. We observed a concordance of >99.8% in genotyping results from genomic DNA and amplified DNA, strongly indicating the ability of both methods used to amplify genomic DNA in a highly representative manner. Furthermore, we were able to achieve a SNP call rate of >98% in both genomic and amplified DNA. The combination of whole-genome amplification and comprehensive SNP linkage analysis offers new opportunities for genetic analysis in clinical trials, disease association studies, and archiving of DNA samples.  相似文献   
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Polyphenols (PPs) are the naturally occurring bioactive components in fruits and vegetables, and they are the most abundant antioxidant in the human diet. Studies are suggesting that ingestion of PPs might be helpful to ameliorate metabolic syndromes that may contribute in the prevention of several chronic disorders like diabetes, obesity, hypertension, and colon cancer. PPs have structural diversity which impacts their bioavailability as they accumulate in the large intestine and are extensively metabolized through gut microbiota (GM). Intestinal microbiota transforms PPs into their metabolites to make them bioactive. Interestingly, not only GM act on PPs to metabolize them but PPs also modulate the composition of GM. Thus, change in GM from pathogenic to beneficial ones may be helpful to ameliorate gut health and associated diseases. However, to overcome the low bioavailability of PPs, various approaches have been developed to improve their solubility and transportation through the gut. In this review, we present evidence supporting the structural changes that occur after metabolic reactions in PPs (curcumin, quercetin, and catechins) and their effect on GM composition that leads to improving overall gut health and helping to ameliorate metabolic disorders.  相似文献   
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Most patients diagnosed with pancreatic cancer are classified as nonoperative candidates based on the contemporary guidelines of resectability. The advent of more potent control of systemic disease using neoadjuvant chemotherapy has enabled more aggressive operative interventions. In our multidisciplinary practice, patients with Stage III, locally advanced pancreatic cancer and superior mesenteric artery (SMA) encasement are now carefully triaged with high quality, preoperative imaging to determine if they can be considered candidates for operative resection with periadventitial dissection of the SMA. Patients displaying a “halo sign,” where the encased SMA remains fully patent and free from arterial invasion, are now candidates for SMA periadventitial dissection. This procedure involves the surgical stripping of the infiltrated neurolymphatic tissue off the SMA leaving behind a bare “skeletonized artery.” Alternatively, the “string sign” involving the SMA confers a more likely case of arterial invasion, where a complete oncologic resection cannot be achieved successfully. This method of patient selection in case of SMA involvement abandons the traditional metrics of circumferential degrees of the arterial encasement to guide surgical decisions. Our institutional approach has allowed us to meaningfully expand our operative methods of resection with the potential for improved longitudinal outcomes to pancreatic cancer patients who were deprived historically from the more effective and possibly curative treatment.  相似文献   
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IntroductionPolio, which is caused by poliovirus, is a contagious, potentially crippling, and deadly disease. Pakistan is one of the countries in which polio is still endemic in the 21st century. In 2019, 146 polio cases were reported across the country with some resulting in deaths. Following the spread of rumors insinuating that children were falling sick after receiving an anti-polio vaccine, a mob attacked and set fire to a small hospital in the Peshawar district in April 2019. The present study investigates readers’ discussions that emerged from Dawn’s online readers’ comments on polio-related news stories in Pakistan.MethodsUsing thematic analysis, we analyzed (N = 2216) comments made by readers in the polio-related news stories published on Dawn.com from January 1, 2012, to March 1, 2020.ResultsSeven major themes emerged from the analysis of the comments: 1) reasons for and challenges resulting in the failure to eradicate polio; 2) proposed solutions and policy changes to eradicate polio; 3) misinformation; 4) criticism, frustration, and shame; 5) comparison of Pakistan to other countries; 6) the internet as a public sphere; 7) suffering, empathy, and appreciation. Overall, our findings suggested that commenters are knowledgeable about polio vaccines and consider polio a serious threat to public health in Pakistan.ConclusionOur study not only validated previous study findings such as reasons, challenges, and issues related to polio vaccination, but also found new challenges in online news sites concerning misinformation on polio and polio vaccination in Pakistan.  相似文献   
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