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91.
Boogerd KJ Wong LY Christoffels VM Klarenbeek M Ruijter JM Moorman AF Barnett P 《Cardiovascular research》2008,78(3):485-493
AIMS: T-box factors Tbx2 and Tbx3 play key roles in the development of the cardiac conduction system, atrioventricular canal, and outflow tract of the heart. They regulate the gap-junction-encoding gene Connexin43 (Cx43) and other genes critical for heart development and function. Discovering protein partners of Tbx2 and Tbx3 will shed light on the mechanisms by which these factors regulate these gene programs. METHODS AND RESULTS: Employing an yeast 2-hybrid screen and subsequent in vitro pull-down experiments we demonstrate that muscle segment homeobox genes Msx1 and Msx2 are able to bind the cardiac T-box proteins Tbx2, Tbx3, and Tbx5. This interaction, as that of the related Nkx2.5 protein, is supported by the T-box and homeodomain alone. Overlapping spatiotemporal expression patterns of Msx1 and Msx2 together with the T-box genes during cardiac development in mouse and chicken underscore the biological significance of this interaction. We demonstrate that Msx proteins together with Tbx2 and Tbx3 suppress Cx43 promoter activity and down regulate Cx43 gene activity in a rat heart-derived cell line. Using chromatin immunoprecipitation analysis we demonstrate that Msx1 can bind the Cx43 promoter at a conserved binding site located in close proximity to a previously defined T-box binding site, and that the activity of Msx proteins on this promoter appears dependent in the presence of Tbx3. CONCLUSION: Msx1 and Msx2 can function in concert with the T-box proteins to suppress Cx43 and other working myocardial genes. 相似文献
92.
P. S. Ramanujam M.D. K. S. Venkatesh M.D. T. Co Barnett M.D. M. J. Fietz M.D. 《Diseases of the colon and rectum》1996,39(1):37-39
PURPOSE: The purpose of this study was to determine the incidence of human papillomavirus deoxyribonucleic acid (HPV DNA) in anal squamous carcinoma. METHODS: HPV DNA in situ hybridization for HPV Types 6, 11, 16, 18, 31, 33, and 35 was performed on the formalin-fixed, paraffinembedded tissue from 53 perianal and anal squamous carcinomas and 10 controls. RESULTS: HPV DNA sequences were identified in 18 of 53 anal squamous carcinomas (34 percent). All 10 controls were negative for HPV DNA. Of the 18 positive patients, 10 were perianal squamous carcinomas, and 8 were anal canal squamous carcinomas. Six of the perianal carcinomas were positive for HPV Types 6 and 11. The remaining four perianal carcinomas and all eight of the anal canal carcinomas were positive for HPV Types 16 and 18. CONCLUSION: HPV DNA sequences can be identified in anal squamous carcinomas. Anal squamous epithelium is another site where HPV infection may carry a risk for malignant transformation. One-third of anal squamous carcinomas may be associated with prior HPV infection. Patients with anogenital HPV infection should be routinely screened for anal squamous lesions. 相似文献
93.
β-Chemokines and neutralizing antibody titers correlate with sterilizing immunity generated in HIV-1 vaccinated macaques 下载免费PDF全文
Jonathan L. Heeney Vera J. P. Teeuwsen Marille van Gils Willy M. J. M. Bogers Carlo De Giuli Morghen Antonia Radaelli Susan Barnett Bror Morein Lennart kerblom Yufei Wang Thomas Lehner David Davis 《Proceedings of the National Academy of Sciences of the United States of America》1998,95(18):10803-10808
One of the obstacles to AIDS vaccine development is the variability of HIV-1 within individuals and within infected populations, enabling viral escape from highly specific vaccine induced immune responses. An understanding of the different immune mechanisms capable of inhibiting HIV infection may be of benefit in the eventual design of vaccines effective against HIV-1 variants. To study this we first compared the immune responses induced in Rhesus monkeys by using two different immunization strategies based on the same vaccine strain of HIV-1. We then utilized a chimeric simian/HIV that expressed the envelope of a dual tropic HIV-1 escape variant isolated from a later time point from the same patient from which the vaccine strain was isolated. Upon challenge, one vaccine group was completely protected from infection, whereas all of the other vaccinees and controls became infected. Protected macaques developed highest titers of heterologous neutralizing antibodies, and consistently elevated HIV-1-specific T helper responses. Furthermore, only protected animals had markedly increased concentrations of RANTES, macrophage inflammatory proteins 1α and 1β produced by circulating CD8+ T cells. These results suggest that vaccine strategies that induce multiple effector mechanisms in concert with β-chemokines may be desired in the generation of protective immune responses by HIV-1 vaccines. 相似文献
94.
Mitochondrial DNA A3243G mutation in patients with early- or late-onset type 2 diabetes mellitus in Hong Kong Chinese 总被引:6,自引:0,他引:6
Ng MC Yeung VT Chow CC Li JK Smith PR Mijovic CH Critchley JA Barnett AH Cockram CS Chan JC 《Clinical endocrinology》2000,52(5):557-564
BACKGROUND: AND OBJECTIVES: The mitochondrial DNA A to G mutation at nucleotide 3243 (mt3243) is associated with a subtype of diabetes characterized by maternal transmission and deafness. We have previously reported a 2.7% prevalence of this mutation in a cohort of young patients with either type 1 or type 2 diabetes. In this study, we aimed to confirm this finding by examining for the prevalence of this mutation in a large-scale study. SUBJECTS AND METHODS: Nine hundred and six unrelated Chinese patients with type 2 diabetes and 213 nondiabetic controls were studied. The presence of mt3243 mutation was determined by polymerase chain reaction amplification and ApaI digestion. RESULTS: This mutation was found in four of 133 (3.0%) patients with early onset (= 40 years) diabetes who also had a positive maternal family history, and in one of 348 (0.3%) patients with late-onset (> 40 years) diabetes and no family history. Basal pancreatic beta-cell function, as assessed by fasting plasma C-peptide, was variable amongst mutation carriers, and did not correlate with the level of heteroplasmy of mutation. CONCLUSIONS: In agreement with most studies, our results suggest that despite the high prevalence of positive maternal family history of diabetes amongst our type 2 diabetic patients, mt3243 mutation was not a major cause of diabetes in either early- or late-onset diabetic patients in Hong Kong. The role of other genetic, environmental and intrauterine factors needs further investigation. 相似文献
95.
An integrative review exploring the physical and psychological harm inherent in using restraint in mental health inpatient settings 下载免费PDF全文
Pauline Cusack PG Cert HE MSc BA Dip. SW. Sue McAndrew PhD MSc BSc Mick McKeown PhD BA DPSN RMN RGN Joy Duxbury PhD MA PG Cert HE BSc. 《International journal of mental health nursing》2018,27(3):1162-1176
In Western society, policy and legislation seeks to minimize restrictive interventions, including physical restraint; yet research suggests the use of such practices continues to raise concerns. Whilst international agreement has sought to define physical restraint, diversity in the way in which countries use restraint remains disparate. Research to date has reported on statistics regarding restraint, how and why it is used, and staff and service user perspectives about its use. However, there is limited evidence directly exploring the physical and psychological harm restraint may cause to people being cared for within mental health inpatient settings. This study reports on an integrative review of the literature exploring available evidence regarding the physical and psychological impact of restraint. The review included both experimental and nonexperimental research papers, using Cooper's (1998) five‐stage approach to synthesize the findings. Eight themes emerged: Trauma/retraumatization; Distress; Fear; Feeling ignored; Control; Power; Calm; and Dehumanizing conditions. In conclusion, whilst further research is required regarding the physical and psychological implications of physical restraint in mental health settings, mental health nurses are in a prime position to use their skills and knowledge to address the issues identified to eradicate the use of restraint and better meet the needs of those experiencing mental illness. 相似文献
96.
97.
Barbara A. Curbow Amy B. Dailey Evelyn C. King-Marshall Tracy E. Barnett Jessica R. Schumacher Shahnaz Sultan Thomas J. George Jr. 《American journal of public health》2015,105(4):e103-e111
Objectives. We aimed to highlight sociodemographic differences in how patients access colonoscopy.Methods. We invited all eligible patients (n = 2500) from 2 academy-affiliated colonoscopy centers in Alachua County, Florida (1 free standing, 1 hospital based), to participate in a precolonoscopy survey (September 2011–October 2013); patients agreeing to participate (n = 1841, response rate = 73.6%) received a $5.00 gift card.Results. We found sociodemographic differences in referral pathway, costs, and reasons associated with obtaining the procedure. Patients with the ideal pathway (referred by their regular doctor for age-appropriate screening) were more likely to be Black (compared with other minorities), male, high income, employed, and older. Having the colonoscopy because of symptoms was associated with being female, younger, and having lower income. We found significant differences for 1 previously underestimated barrier, having a spouse to accompany the patient to the procedure.Conclusions. Patients’ facilitators and barriers to colonoscopy differed by sociodemographics in our study, which implies that interventions based on a single facilitator will not be effective for all subgroups of a population.Colorectal cancer (CRC), the second leading cause of US cancer deaths in 2013 (50 830),1 is not distributed equally. Nationally, it is estimated that incidence is 25% higher, and mortality from CRC 50% higher, in Black Americans than in Whites.2,3 Most CRC diagnoses follow evaluation by colonoscopy. Although consumers have a range of CRC screening tests, from least invasive (fecal occult blood test, fecal immunochemical test) to most invasive (sigmoidoscopy, colonoscopy),4 if polyps are indicated, a colonoscopy is required as follow-up. Thus, colonoscopy is both an entry point and a pivotal event in the process of preventing, detecting, and treating CRC. CRC can be prevented through the removal of precancerous polyps or detected at an early, easily treatable stage5; findings indicate6 that colonoscopy with polypectomy reduces mortality from CRC by 53%. Although rates of CRC screening have increased,3 there is need for improvement. More than one third of Americans are not in compliance with screening guidelines,7 with rates being lower in the southern United States.8In 2008, Etzioni et al.9 presented a model of patient and provider-level factors that influence decision-making in colon cancer and that can lead to health disparities in disease recurrence and survival. The Etzioni model identifies key points of vulnerability in the treatment process where the potential to achieve high-quality, guideline-recommended care can be lost. The model captures patients after surgery, beginning with the decision to refer patients to a medical oncologist for adjuvant treatment; it is relevant because there is considerable evidence of inequities in who receives adjuvant treatment based on older age,10,11 comorbidities,12,13 low income,7 coverage with Medicaid rather than Medicare,13 Black race,14 female gender,15,16 and being unmarried.9We propose that this model starts too late in the process; health disparities originate prior to colonoscopy and can increase at each decision point along a continuum. In an elaborated model (Figure 1), we suggest that CRC health disparities research should begin with an investigation of entry into the health care system and the subsequent pathways to colonoscopy. Referral patterns, costs, and patient demographics influence patient access to care, colonoscopy compliance, and postcolonoscopy decision-making.Open in a separate windowFIGURE 1—Pathways to colonoscopy, treatment, and outcomes. 相似文献
98.
Kajua B Lor Julie T Truong Eric J Ip Mitchell J Barnett 《American journal of pharmaceutical education》2015,79(2)
Objective. To determine the impact of a single, 3-day intervention on empathy levels as measured by the validated Jefferson Scale of Empathy-Health Profession Students version (JSE-HPS).Methods. Forty second-year student pharmacists were recruited to participate in a non-blinded prospective study. Subjects were randomized to an intervention group (n=20) or control group (n=20) and completed the JSE-HPS at baseline, 7 days postintervention, and 90 days postintervention. The intervention group consisted of a 3-day simulation, each day including a designated activity with loss of dominant hand usage, vision, and speech.Results. The 3-day simulation increased empathy levels in the intervention group compared to the control group 7 days postintervention (p=0.035). However, there were no effects on empathy levels 90 days postintervention (p=0.38).Conclusion. Empathy scores increased but were not sustained in the long-term with a 3-day empathy intervention. 相似文献
99.
100.
BACKGROUND: Pre-medication with droperidol has been used to improve sedation during endoscopy, especially in patients with a history of alcohol or narcotic abuse. We studied whether routine use of droperidol pre-endoscopic retrograde cholangiopancreatography (ERCP) could improve patient and physician satisfaction with sedation. METHODS: Sixty-seven patients undergoing routine ERCP were enrolled in this double-blind placebo-controlled study. Patients were given either parenteral normal saline solution or 5 mg of droperidol 15 minutes before the procedure. After the ERCP, several parameters of procedural sedation were scored on an ordinal scale by the endoscopist, the endoscopy nurse, and the recovered patient. In addition, a follow-up telephone call was made to the patient after 24 hours. RESULTS: The mean procedural room time was similar in the two groups. Nearly 25% less meperidine and diazepam was used in the droperidol-treated patients, making the overall medication cost similar in both groups. The mean recovery room time was 113 minutes for the placebo group and 106 minutes for the droperidol group. Droperidol premedication significantly decreased post-procedure nausea and vomiting, reduced gagging at intubation, and decreased retching during the procedure. Droperidol also improved physician (p = 0.001), nurse (p = 0.001), and patient (p = 0.0001) impressions of overall sedation and decreased the need for physical restraint during the procedure. Droperidol significantly increased the number of patients with no memory of the procedure. CONCLUSION: Droperidol improved overall patient, physician, and nurse satisfaction with sedation during ERCP. It also reduced post-ERCP nausea and vomiting without increasing recovery time or medication cost. Droperidol is recommended for routine pre-ERCP sedation. (Gastrointest Endosc 2000;52:362-6). 相似文献