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1.
Molecular probes that are tightly linked to and flank the Duchenne muscular dystrophy (DMD) locus, have been used to characterize DMD mutations and diagnose female carriers. Deletions within the Xp21 region were identified for 8 of 71 families studied. Using both DNA and CK studies, accurate (96 to 98%) carrier or noncarrier diagnoses were made for 51 of 75 females at risk in 24 families with a single affected male. DNA studies resulted in an alteration of predicted risk in 40% of the cases. Recombinant diagnostic methods are useful for carrier detection in families with one or more affected males.  相似文献   
2.
While an unstable CTG triplet repeat expansion is responsible for myotonic dystrophy, the mechanism whereby this genetic defect induces the disease remains unknown. To detect proteins binding to CTG triplet repeats, we performed bandshift analysis using as probes double- stranded DNA fragments having CTG repeats [ds(CTG)6-10] and single- stranded oligonucleotides having CTG repeats ss(CTG)8 or RNA CUG triplet repeats (CUG)8. The source of protein was nuclear and cytoplasmic extracts of HeLa cells, fibroblasts and myotubes. Proteins binding to the double-stranded DNA repeat [ds(CTG)6-10], were inhibited by nonlabeled ds(CTG)6-10, but not by a non-specific DNA fragment (USF/AD-ML). Another protein binding to ssCTG probe and RNA CUG probe was inhibited by nonlabeled (CTG)8 and (CUG)8. Nonlabeled oligos with different triplet repeat sequences, ss(CAG)8 or ss(CGG)8, did not inhibit binding to the ss(CTG)8 probe. However, when labeled as probes, the (CAG)8 and (CGG)8 bound to proteins distinct from the CTG proteins and binding was inhibited by nonlabeled (CAG)8 or (CGG)8 respectively. The protein binding only to the RNA repeat (CUG)8 was inhibited by nonlabeled (CUG)8 but not by nonlabeled single- or double-stranded CTG repeats. Furthermore, the CUG-BP exhibited no binding to an RNA oligonucleotide of triplet repeats of the same length but having a different sequence, CGG. The CUG binding protein was localized to the cytoplasm, whereas dsDNA binding proteins were localized to the nuclear extract. Thus, several trinucleotide binding proteins exist and their specificity is determined by the triplet sequence. The novel protein, CUG-BP, is particularly interesting since it binds to triplet repeats known to be present in myotonin protein kinase mRNA which is responsible for myotonic dystrophy.   相似文献   
3.
We present a patient with 45,X/46,X,+r(X) mosaicism and lack of inactivation of either the normal or the ring X in the 46,X,+r(X) cells. The patient has mental retardation, syndactyly, minor facial anomalies, and a congenital heart defect. Although most patients with 45,X/46,X,+r(X) have the Ullrich-Turner syndrome, 2 previously described patients with this karyotype also had a distinct phenotype consisting of severe mental retardation, syndactyly, and abnormal face. The unusually severe phenotype in these patients was thought to be due to lack of X-inactivation of the ring X chromosome. The findings in our patient support this hypothesis.  相似文献   
4.
Applications of recombinant DNA to pathologic diagnosis   总被引:1,自引:0,他引:1  
Recombinant DNA techniques are contributing to the understanding of the pathogeneses of genetic, neoplastic, and viral diseases, and are used in the diagnosis of certain genetic and viral diseases. Such techniques will have wider application in the future and will play an increasing role in the clinical laboratory. The technology of this field rests upon the cleavage of DNA by certain enzymes, restriction endonucleases, and upon the ability to locate specific sequences of nucleotides in a cleaved DNA sample by using known fragments of DNA ("probes") labeled with radioisotopes or biotin. To produce useful probes, one "clones" multiple copies of the same DNA fragment in bacteria. The use of DNA probes in the clinical laboratory is valuable in antenatal diagnosis, genetic counseling, and post-natal diagnosis of genetic diseases, especially hematologic diseases and inborn errors of metabolism. DNA probes can also be used to detect viral genetic material in clinical specimens.  相似文献   
5.
Early survivors of pediatric cancer are at increased risk of experiencing chronic conditions; however, little is known about the morbidity burden in this population. In this observational cohort study of commercially insured pediatric cancer survivors in the United States (2009–2014), we find that 22.5% of survivors had one chronic condition, and 36.3% had multiple. Compared with survivors without chronic conditions, the presence of multiple conditions significantly increased the odds of an emergency department visit by 70% (odds ratios [OR], 1.7; 95% confidence interval [CI], 1.4–2.1) and of a hospitalization almost four‐fold (OR, 3.8; 95% CI], 2.5–5.5). Findings are important for informing pediatric survivorship care plans in the years following completion of therapy.  相似文献   
6.
7.
Objective:To determine whether changes in primary attending (PA) doctor coverage frequency caused an increase in orthodontic treatment time or a decrease in the quality of treatment results in a postgraduate orthodontic clinic. The effect of T1 Peer Assessment Rating (PAR) scores on PA doctor coverage frequency, treatment times, and results was also evaluated.Materials and Methods:A sample of 191 postorthodontic subjects was divided into three groups based on PA doctor coverage (high, medium, or low). Treatment times, treatment results, and other variables were compared between the three PA coverage groups. Additionally, the sample was divided into three groups based on T1 PAR scores. Attending coverage frequency, treatment times, and results were compared between the T1 PAR groups.Results:No statistically significant differences were found in treatment time (P  =  .128) or results (P  =  .052). There were no statistically significant differences in the mean scores for T1 PAR (P  =  .056), T2 PAR (P  =  .602), patient age at T1 (P  =  .747), total appointments (P  =  .128), missed appointments (P  =  .177), or cancelled appointments (P  =  .183). Statistically significant differences were found between the low T1 PAR group and the medium and high T1 PAR groups (attending coverage, P  =  .008; results, P < .001; treatment time, P  =  .001).Conclusions:Under the conditions of this study, variations in PA doctor coverage frequency did not lengthen orthodontic treatment or reduce the quality of treatment results. Low T1 PAR scores were associated with less PA coverage, less change in PAR, and shorter treatment times.  相似文献   
8.
Diabetic skin wounds lack the ability to heal properly and constitute a major and significant complication of diabetes. Nontraumatic lower extremity amputations are the number one complication of diabetic skin wounds. The complexity of their pathophysiology requires an intervention at many levels to enhance healing and wound closure. Stem cells are a promising treatment for diabetic skin wounds as they have the ability to correct abnormal healing. Stem cell factor (SCF), a chemokine expressed in the skin, can induce stem cells migration, however the role of SCF in diabetic skin wound healing is still unknown. We hypothesize that SCF would correct the impairment and promote the healing of diabetic skin wounds. Our results show that SCF improved wound closure in diabetic mice and increased HIF‐1α and vascular endothelial growth factor (VEGF) expression levels in these wounds. SCF treatment also enhanced the migration of red fluorescent protein (RFP)‐labeled skin stem cells via in utero intra‐amniotic injection of lenti‐RFP at E8. Interestingly these RFP+ cells are present in the epidermis, stain negative for K15, and appear to be distinct from the already known hair follicle stem cells. These results demonstrate that SCF improves diabetic wound healing in part by increasing the recruitment of a unique stem cell population present in the skin.  相似文献   
9.
Older adults are among the highest at risk for completing suicide, and they are more likely to seek mental health services from providers outside of traditional mental health care, but providers across the spectrum of care have limited training in suicide risk assessment and management and particularly lack training in suicide prevention for older adults. An educational program was developed to increase awareness and improve suicide risk assessment and management training for a range of healthcare providers who may see older adults in their care settings. One hundred thirty-two participants from two Veterans Affairs Medical Centers participated in a 6.5-hour-long workshop in the assessment and management of suicide risk in older adults. Participants were asked to complete pre- and postworkshop case notes and report on subjective changes in knowledge, attitudes, and confidence in assessment and managing suicide risk in older adults. Participants included social workers, nurses, physicians, psychologists, and occupational therapists from a variety of care settings, including outpatient and inpatient medical, outpatient and inpatient mental health, specialty clinics, home, and community. After the workshop, participants demonstrated improvement in the overall quality of case notes (P = .001), greater ability to recognize important conceptual suicide risk categories (P = .003), and reported heightened awareness of the importance of late-life suicide. The results suggest that educational training may have beneficial effect on the ability of multidisciplinary care providers to identify and manage suicide risk in elderly adults.  相似文献   
10.

Background

Strategies to improve public health may benefit from targeting specific lifestyles associated with poor health behaviors and outcomes. The aim of this study was to characterize and examine the relationship between health and lifestyle-related attitudes (HLAs) and self-rated health and life-satisfaction.

Methods

Secondary analyses were conducted on data from a 2012 community wellness survey in Kirklees, UK. Using a validated HLA tool, respondents (n?=?9130) were categorized into five segments: health conscious realists (33%), balanced compensators (14%), live-for-todays (18%), hedonistic immortals (10%), and unconfident fatalists (25%). Multivariate regression was used to examine whether HLAs could explain self-rated health using the EQ-5D visual analog scale (EQ-VAS) and life-satisfaction. Health conscious realists served as the reference group.

Results

Self-rated health differed by HLA, with adjusted mean EQ-VAS scores being significantly higher (better) among balanced compensators (1.15, 95% CI 0.27, 2.03) and lower scores among unconfident fatalists (??9.02, 95% CI ??9.85, ??8.21) and live-for-todays (??1.96, 95% CI ??2.80, ??1.14). Balanced compensators were less likely to report low life-satisfaction (OR 0.75, 95% CI 0.62, 0.90), while unconfident fatalists were most likely to have low life-satisfaction (OR 3.51, 95% CI 2.92, 4.23).

Significance

Segmentation by HLA explained differences in self-rated health and life-satisfaction,with unconfident fatalists being a distinct segment with significantly worse healthperceptions and life-satisfaction. Health promotion efforts may benefit from considering the HLAsegment that predominates a patient group, especially unconfident fatalists.
  相似文献   
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