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51.
TP63 germ‐line mutations are responsible for a group of human ectodermal dysplasia syndromes, underlining the key role of P63 in the development of ectoderm‐derived tissues. Here, we report the identification of two TP63 alleles, G134V (p.Gly173Val) and insR155 (p.Thr193_Tyr194insArg), associated to ADULT and EEC syndromes, respectively. These alleles, along with previously identified G134D (p.Gly173Asp) and R204W (p.Arg243Trp), were functionally characterized in yeast, studied in a mammalian cell line and modeled based on the crystal structure of the P63 DNA‐binding domain. Although the p.Arg243Trp mutant showed both complete loss of transactivation function and ability to interfere over wild‐type P63, the impact of p.Gly173Asp, p.Gly173Val, and p.Thr193_Tyr194insArg varied depending on the response element (RE) tested. Interestingly, p.Gly173Asp and p.Gly173Val mutants were characterized by a severe defect in transactivation along with interfering ability on two DN‐P63α‐specific REs derived from genes closely related to the clinical manifestations of the TP63‐associated syndromes, namely PERP and COL18A1. The modeling of the mutations supported the distinct functional effect of each mutant. The present results highlight the importance of integrating different functional endpoints that take in account the features of P63 proteins' target sequences to examine the impact of TP63 mutations and the associated clinical variability.  相似文献   
52.
BACKGROUND: The objectives of this prospective study were: (i) to compare the efficacy of 1-week with 2-week pantoprazole-based triple therapy and (ii) to evaluate the impact of clarithromycin resistance on Helicobacter pylori (H. pylori) eradication rates. METHODS: Eighty dyspeptic patients were randomly allocated to two groups. The first group (PAC-1, n=40) received pantoprazole 40 mg, amoxicillin 1000 mg, and clarithromycin 500 mg twice a day for one week, and the second group (PAC-2, n=40) received the same regimen for two weeks. Endoscopy was repeated one month after the end of the treatment. RESULTS: DNA extraction for clarithromycin resistance could not be performed in seven cases. Five cases were lost to follow-up. Clarithromycin resistance was found to be 44.1% (15/34) in the PAC-1 group and 58.8% (20/34) in the PAC-2 group (p>0.05). Eradication was achieved in 16 (PP: 47.1%, ITT: 44.4%) and 25 (PP:73.5%, ITT: 67.6%) patients in the PAC-1 and PAC-2 groups, respectively (p>0.05). H. pylori was eradicated in 4 of 15 (PP: 26.7%, ITT: 26.7%) clarithromycin-resistant patients in the PAC-1 group and in 12 of 20 (PP: 60%, ITT: 60%) clarithromycin-resistant patients in the PAC-2 group (p>0.05). Among the clarithromycin-sensitive ones, eradication was achieved in 12 of 19 (PP: 63.2%, ITT: 57.1%) patients in the PAC-1 group and in 13 of 14 (PP: 92.8%, ITT: 76.5%) patients in the PAC-2 group (p>0.05). CONCLUSION: Although the 2-week regimen of pantoprazole-based triple therapy was effective for H. pylori eradication in clarithromycin-sensitive cases, highly effective H. pylori eradication protocols are needed for clarithromycin-resistant ones.  相似文献   
53.
54.
Reactive oxygen species (ROS) appear to play a role in limiting both cellular and organismic lifespan. However, because of their pleiotropic effects, it has been difficult to ascribe a specific role to ROS in initiating the process of cellular senescence. We have studied the effects of oxidative DNA damage on cell proliferation, believing that such damage is of central importance to triggering senescence. To do so, we devised a strategy to decouple levels of 8-oxoguanine, a major oxidative DNA lesion, from ROS levels. Suppression of MTH1 expression, which hydrolyzes 8-oxo-dGTP, was accompanied by increased total cellular 8-oxoguanine levels and caused early-passage primary and telomerase-immortalized human skin fibroblasts to rapidly undergo senescence, doing so without altering cellular ROS levels. This senescent phenotype recapitulated several salient features of replicative senescence, notably the presence of senescence-associated beta-galactosidase (SA beta-gal) activity, apparently irreparable genomic DNA breaks, and elevation of p21Cip1, p53, and p16INK4A tumor suppressor protein levels. Culturing cells under low oxygen tension (3%) largely prevented the shMTH1-dependent senescent phenotype. These results indicate that the nucleotide pool is a critical target of intracellular ROS and that oxidized nucleotides, unless continuously eliminated, can rapidly induce cell senescence through signaling pathways very similar to those activated during replicative senescence.  相似文献   
55.

Community implementation of evidence-based practices (EBPs) for Attention Deficit/Hyperactivity Disorder (ADHD) is greatly lacking. A recent randomized community-based trial of an EBP for ADHD (Supporting Teens’ Autonomy Daily; STAND) demonstrated suboptimal implementation and effectiveness outcomes. In the present study, we conducted an Innovation Tournament (IT) with agency staff stakeholders (N?=?26) to identify barriers to successful implementation of STAND and implementation strategies for a revised service delivery model. We conducted member-checking of agency staff-generated ideas with parents (N?=?226) and subsequent querying of additional parent (N?=?226) and youth-generated (N?=?205) strategies to improve care. Go-Zone plots were utilized to identify strategies with the highest feasibility and importance. Practical barriers (i.e., transportation, scheduling difficulties) and parent/youth engagement were the most commonly cited obstacles to successful implementation of STAND in community contexts. Eighteen “winning” implementation strategies were identified that survived member checking. These were classified as train and educate stakeholders (n?=?5; e.g., train agency supervisors to deliver supervision, digitize treatment materials and trainings), engage consumers (n?=?9; e.g., begin treatment with rapport building sessions, increase psychoeducation), provide interactive assistance (n?=?2; e.g., add group supervision, increase roleplay in supervision), and use of evaluative/iterative strategies (n?=?2; e.g., perform fidelity checks, supervisor review of session recordings). Parents and youth desired longer duration of treatment and increased focus on maintenance. Strategies will be developed and tested as part of a pilot effectiveness trial designed to refine STAND’s service delivery model.

Trial Registration NCT02694939 www.clinicaltrials.gov

  相似文献   
56.
Patients with incarcerated abdominal wall hernias (AWHs) are often encountered in emergency care units. Despite advances in anesthesia, antisepsis, antibiotic therapy, and fluid therapy, the morbidity and mortality rates for these patients remain high. Between 2006 and 2011, we retrospectively analyzed the cases of 131 patients who underwent emergency surgery for incarcerated abdominal wall hernias. Of these, there were 70 women (53.4%) and 61 men (46.6%) with an average age of 63.3 ± 17.4 years (range, 17–91 years). Morbidity was observed in 28 patients (21.4%), and the mortality rate was 2.3%. Intestinal resection, presence of concomitant disease, and general anesthesia were the independent variants that affected morbidity of patients with incarcerated abdominal wall hernias.  相似文献   
57.
Cardiorespiratory response to exercise in patients with thalassemia major   总被引:1,自引:0,他引:1  
The cardiorespiratory response to exercise was examined in 13 patients, 12 to 22 yr of age, who were in stable condition while receiving regular transfusions for thalassemia major. Before transfusion (Hgb, 10.8 g/dl), the patients had reduced peak oxygen consumption for body weight (by 25%, p less than 0.002) in comparison with 20 age- and sex-matched control subjects (Hgb, 13.8 g/dl). The ventilatory equivalent for carbon dioxide was significantly reduced at all work rates, and end-tidal PCO2 was abnormally high (46.3 versus 40.7 mm Hg, p less than 0.001), but ventilatory reserve, as estimated from pulmonary function tests, was normal. Both heart rate and cardiac output (as estimated by the indirect Fick method) were abnormally high during exercise; at an oxygen consumption of 19 ml/min/kg, heart rate was 13% higher (p less than 0.01) and, at 16 ml/min/kg, cardiac output was 28% higher (p less than 0.001) in the patients than in the control subjects. Nine patients were retested 3 to 8 days after transfusion (Hgb, 13.0 g/dl, p50, 26.4 mm Hg). Neither ventilatory nor circulatory abnormalities improved significantly. In patients 12 to 22 yr of age in stable condition with thalassemia major, we conclude: cardiac output, estimated by the CO2 rebreathing method, is high and arteriovenous O2 extraction is low during exercise; the high cardiac output during exercise is associated with hypoventilation; the high cardiac output is independent of short-term changes in hemoglobin concentration associated with transfusion.  相似文献   
58.
The pathogenesis of the late asthmatic response has been of interest due to the fact that its development has been associated with airway obstruction, airway inflammation, and airway hyperresponsiveness: all features of chronic asthma. In order to study more precisely late responses, a number of animal models have been developed. Previous reports have described alterations in airway mechanics at both 3 to 6 and 17 h after antigen challenge in sensitized guinea pigs. In these experiments, however, animals were challenged through the nose with aerosolized antigen, and airway conductance was measured using whole body plethysmography while the animals breathed through the upper airways. In rats similarly challenged, the predominant immediate change in resistance occurs in the upper airways. The purpose of this study, therefore, was to evaluate the contribution made by both the upper and lower airways to late changes after allergen challenge in guinea pigs. Outbred female Hartley guinea pigs were actively or passively sensitized (IgG1 antibody response) to three different antigens and challenged either by direct tracheal insufflation (sheep gamma globulin [SGG] or oxazolone-human serum albumin [OX-HSA]) or by aerosolization (ovalbumin [OA]). Lung resistance (RL) and dynamic compliance (Cdyn) were measured in anesthetized guinea pigs through a tracheostomy tube, and specific airway conductance (SGaw) was measured in unanesthetized, nose-breathing guinea pigs using a whole body plethysmograph. Late responses were defined as a RL greater than the mean + 2 SD RL or as a decrease in SGaw from baseline greater than 2 SD from the placebo-challenged (bovine serum albumin) group.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
59.
A 35-yr-old woman is described as having atypical McCune-Albright syndrome, associated with acromegaly and hyperprolactinemia due to pituitary adenoma. The patient did not present sexual precocity, but primary amenorrhea. After transphenoidal adenomectomy, the GH plasma levels returned to normal, whereas the PRL values decreased; bromocriptine therapy normalized PRL levels and induced ovulatory menses. After 4 uneventful yr the patient developed relapse of active acromegaly that did not recover after a second neurosurgical exploration. Bromocriptine treatment maintained normal PRL levels but did not significantly reduce GH ones; the association with long-acting somatostatin analog SMS 201-995 by continuous sc pump infusion induced definitive control of GH and somatomedin-C secretion. These results suggest an additive inhibitory effect on GH secretion exerted by the two drugs.  相似文献   
60.
Diarrhea is a significant problem in patients with acquired immunodeficiency syndrome (AIDS). The aim of this study was to determine octreotide effectiveness in refractory AIDS-associated diarrhea. In a 3-week protocol, 129 patients with a stool weight of >500 g/day despite standard antidiarrheal therapy were randomized to receive octreotide or placebo (3:2 ratio). Octreotide dose was increased 100 μg weekly to a maximum of 300 μg three times a day based on weekly 72-hour stool collections. Subsequently, patients received open-label octreotide at doses of up to 500 μg three times a day. A 30% decrease in stool weight defined response. After 3 weeks, 48% of octreotide- and 39% of placebo-treated patients had responded (P = 0.43). At 300 μg three times a day, 50% of octreotide- and 30.1% of placebo-treated patients responded (P = 0.12). At a baseline stool weight of 1000–2000 g/day, 57% of octreotide- and 25% of placebo-treated patients responded (P = 0.06). Response rates based on CD4 counts, diarrhea duration, body weight, human immunodeficiency virus risk factor, and presence or absence of pathogens showed no benefit of octreotide. Adverse events were more frequent in the octreotide-treated group. In the doses studied, octreotide was not more effective than placebo in patients with refractory AIDS-associated diarrhea. This lack of effectiveness may be attributable to inadequate sample size, doses, and duration of study treatment.  相似文献   
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