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101.
T lineage commitment occurs in a discrete, stage-specific manner during thymic ontogeny. Intrathymic precursor transfer experiments and the identification of CD4(+)8+ double-positive (DP), V alpha 14J alpha 18 natural T (iNKT) cells suggest that commitment to this lineage might occur at the DP stage. Nevertheless, this matter remains contentious because others failed to detect V alpha 14J alpha 18-positive iNKT cells that are CD4(+)8+. In resolution to this issue, we demonstrate that retinoic acid receptor-related orphan receptor gamma (ROR gamma)0/0 thymi, which accumulate immature single-positive (ISP) thymocytes that precede the DP stage, do not rearrange V alpha 14-to-J alpha 18 gene segments, suggesting that this event occurs at a post-ISP stage. Mixed radiation bone marrow chimeras revealed that RORgamma functions in an iNKT cell lineage-specific manner. Further, introgression of a Bcl-x(L) transgene into ROR gamma(0/0) mice, which promotes survival and permits secondary rearrangements of distal V alpha and J alpha gene segments at the DP stage, rescues V alpha 14-to-J alpha 18 recombination. Similarly, introgression of a rearranged V alpha 14J alpha 18 transgene into ROR gamma(0/0) mice results in functional iNKT cells. Thus, our data support the "T cell receptor-instructive (mainstream precursor) model" of iNKT cell lineage specification where V alpha 14-to-J alpha 18 rearrangement, positive selection, and iNKT cell lineage commitment occur at or after the DP stage of ontogeny.  相似文献   
102.
103.

Objectives

Immune checkpoint inhibitors (ICIs) can successfully treat cancer, but their use can be hindered by serious immune-related adverse events. We report six patients receiving ICIs who presented with de novo myositis.

Methods

We identified patients with myositis who were receiving ICIs between January 2004 and September 2016 at The University of Texas MD Anderson Cancer Center.

Results

Six patients developed de novo myositis. The mean age was 64.3 years and five patients were male. Cancer types included melanoma, urothelial carcinoma, renal cell carcinoma, and prostate cancer. ICI regimens included single-agent ipilimumab (n = 1), pembrolizumab (n = 1), or atezolizumab (n = 1); nivolumab and ipilimumab (n = 3). The median time to development of de novo myositis from first infusion was 5.4 weeks (range: 2.1–17.1 weeks). All patients with myositis had elevated levels of creatinine kinase, ranging from 514 to 13,710 U/L. Two of them developed rhabdomyolysis, one with concurrent myocarditis. Five patients were treated with 1–2 mg/kg corticosteroids, with variable response rates; one patient received nonsteroidal anti-inflammatory drugs. Two patients with myositis died as a result of cancer progression.

Conclusion

We found several occurrences of de novo myositis following ICI therapy. These preliminary data suggest that myositis can occur early after onset of ICI therapy with serious adverse outcomes.  相似文献   
104.
Teicoplanin formulations are marketed as antibiotic mixtures with several compounds that share the same core structure. Recent studies conducted in vitro have reported differences in the composition ratio of different teicoplanin products. In this retrospective study, we examined the trough blood concentration of the originator brand and a generic teicoplanin product. Target patients were retrospectively assigned to the originator (Targocid) or generic group. The groups were matched 1:1 using propensity scores. The initial trough blood concentration analysis identified 44 matches. In both groups, the median dosing day for the first measurements was 4, respectively. The initial trough blood concentration of the originator group was significantly higher (mean ± SD, 16.3 ± 4.5 mg/L) than that of the generic group (12.8 ± 4.7 mg/L; 95% CI, ?5.4 to ?1.6). A significant difference was observed in the frequency of serum creatinine elevation in the study of the frequency of adverse events using Common Terminology Criteria for Adverse Events (originator group, 41.9% vs generic group, 20.9%). In cases where discontinuation was necessary due to side effects, there were three patients in the originator group and one patient in the generic group. This study found that trough blood concentration differed between formulations. Therefore, correction might be necessary while monitoring drug concentration in the blood. Trough blood concentrations are used as surrogate markers for efficacy and safety, so further studies on differences in efficacy and safety between formulations are required.  相似文献   
105.

Objective

The goal of this study was to develop and assess intra- and interrater reliability and validity of a clinical evaluation tool for breast cancer–related lymphedema, for use in the context of outcome evaluation in clinical trials.

Design

Blinded repeated measures observational study.

Setting

Outpatient research laboratory.

Participants

Breast cancer survivors with and without lymphedema (N=71).

Interventions

Not applicable.

Main Outcome Measure

The assessment of intraclass correlation coefficients (ICCs) for the Breast Cancer–Related Lymphedema of the Upper Extremity (CLUE) standardized clinical evaluation tool.

Results

Intrarater reliability for the CLUE tool was ICC: 0.88 (95% confidence interval [95% CI], 0.71-0.96). Interrater reliability for the CLUE tool was ICC: 0.90 (95% CI, 0.79-0.95). Concurrent validity of the CLUE score (Pearson r) was 0.79 with perometric interlimb difference and 0.53 with the Norman lymphedema overall score.

Conclusions

The CLUE tool shows excellent inter- and intrarater reliability. The overall CLUE score for the upper extremity also shows moderately strong concurrent validity with objective and subjective measures. This newly developed clinical, physical assessment of upper extremity lymphedema provides standardization and a single score that accounts for multiple constructs. Next steps include evaluation of sensitivity to change, which would establish usefulness to evaluate intervention efficacy.  相似文献   
106.
目的 :应用六西格玛(6σ)理论分析临床干化学检验项目质量控制数据,评价其分析性能,设计质量控制规则,并指导其质量改进。方法:收集2014年度临床干化学18个检验项目室内质量控制及室间质量评价的数据,按照生物学变异的质量规范(allowable total error,TEa)标准,使用Bio-Rad公司的Unity Real Time软件进行操作,计算σ值并绘制操作过程规范(OPSpecs)图和西格玛度量图,评价检验项目分析性能,设计质量控制方案;计算检验项目的质量目标指数(quality goal index,QGI),查找导致性能不佳的主要原因,提出优先改进方法。结果:18个临床干化学检验项目中,以生物学变异质量规范TEa取期望值为例,6个(33%)项目的性能大于6σ,1个(6%)大于4σ,11个(61%)小于3σ。所有项目的平均σ值4.23。在总分析性能未达到6σ的检验项目中,8个项目(QGI<0.8)需优先改进精密度,占67%;3个项目(0.8≤QGI1.2)需优先改进准确度,占8%。18个干化学项目最终质控方案是为,1个项目选择了最佳水平的生物学变异的质量规范,6个项目选择了期望水平,5个项目选择了最低水平。本实验室目前钠、氯、钙、碱性磷酸酶和白蛋白、总蛋白水平检测的性能不能满足最低水平生物学变异质量规范的要求,可降低质控目标的设置等级。结论:6σ质量管理方法可有效评价临床干化学检测性能,设计个性化的质量控制方案可更有效地控制测检质量,有助于不断提高临床实验室生化检验项目质量水平。  相似文献   
107.
Cohen NA  Stead SW 《Chest》2008,133(6):1489-1494
Specialists in pulmonary and critical care medicine frequently perform invasive procedures that may require sedation or anesthesia for patient comfort. The number and complexities of interventional pulmonary procedures that can be performed in the bronchoscopy suite or critical care unit continues to expand. Procedures that formerly were done only in the operating room on inpatients are now done routinely in the office, ambulatory surgery center, or hospital outpatient department. No matter the setting, the key to successfully performing these procedures is a safe, pain-free environment for the patient. Anesthesia care and procedural sedation services share the goals of providing the patient comfort during a painful procedure and the operating physician an acceptable working environment. Historically, anesthesiologists have applied the expertise gained in managing anesthesia for major surgeries to sedation care for minor procedures. While the supply of anesthesiologists and anesthetists has shown only a modest increase, the growth in minimally invasive procedures has been explosive in recent years. To meet demand, a service, originally known as conscious sedation and now referred to as moderate sedation, has become common, in which the operating physician supervises a specially trained sedation nurse. This article will provide a clinical definition of moderate sedation and then focus on ways to properly code and bill for pulmonary procedures performed with moderate sedation.  相似文献   
108.
Although 12 g/day sulbactam/ampicillin (SBT/ABPC) is approved in Japan, differences in the frequency of adverse effects induced by conventional (≤6 g/day) and high (≥9 g/day) doses remain unclear. We performed a retrospective observational study on SBT/ABPC-treated hospitalized adult patients with pneumonia from October 2015 to January 2018 to compare the safety between high and low doses. Patients were divided into high-dose (≥9 g/day, n = 200) and low-dose (≤6 g/day, n = 246) groups. We used logistic regression to determine propensity scores for the high-dose and low-dose groups and compared the incidence of adverse effects after propensity score adjustment (n = 200 in each group). Following propensity score adjustment, the frequency of elevated alanine aminotransferase (ALT) level was still significantly higher in the high-dose group than in the low-dose group (21% versus 11%, p = 0.006). In contrast, the frequencies of elevated alkaline phosphatase, aspartate aminotransferase, and serum creatinine levels and decreased white blood cell and platelet counts, and incidence of anemia, were not. Changes in blood urea nitrogen levels, erythrocyte count, and hematocrit were not significantly different between the two dose groups. There were two cases of rash reported to the Pharmaceuticals and Medical Devices Agency as an adverse effect in the high-dose group. Thirty-day mortality rates were not significantly different after propensity score adjustment. Our analysis suggests that an increase in the ALT grade was more frequent in patients treated with a daily dose of SBT/ABPC of ≥9 g.  相似文献   
109.
Although it is well established that neural cells are ectodermal derivatives in bilaterian animals, here we report the surprising discovery that some of the pharyngeal neurons of sea urchin embryos develop de novo from the endoderm. The appearance of these neurons is independent of mouth formation, in which the stomodeal ectoderm joins the foregut. The neurons do not derive from migration of ectoderm cells to the foregut, as shown by lineage tracing with the photoactivatable protein KikGR. Their specification and development depend on expression of Nkx3-2, which in turn depends on Six3, both of which are expressed in the foregut lineage. SoxB1, which is closely related to the vertebrate Sox factors that support a neural precursor state, is also expressed in the foregut throughout gastrulation, suggesting that this region of the fully formed archenteron retains an unexpected pluripotency. Together, these results lead to the unexpected conclusion that, within a cell lineage already specified to be endoderm by a well-established gene regulatory network [Peter IS, Davidson EH (2010) Dev Biol 340:188-199], there also operates a Six3/Nkx3-2-dependent pathway required for the de novo specification of some of the neurons in the pharynx. As a result, neuroendoderm precursors form in the foregut aided by retention of a SoxB1-dependent pluripotent state.  相似文献   
110.
The crystalline photoreceptor lattice in the Drosophila eye is a paradigm for pattern formation during development. During eye development, activation of proneural genes at a moving front adds new columns to a regular lattice of R8 photoreceptors. We present a mathematical model of the governing activator-inhibitor system, which indicates that the dynamics of positive induction play a central role in the selection of certain cells as R8s. The "switch and template" patterning mechanism we observe is mathematically very different from the well-known Turing instability. Unlike a standard lateral inhibition model, our picture implies that R8s are defined before the appearance of the complete group of proneural cells. The model reproduces the full time course of proneural gene expression and accounts for specific features of the refinement of proneural groups that had resisted explanation. It moreover predicts that perturbing the normal template can lead to eyes containing stripes of R8 cells. We observed these stripes experimentally after manipulation of the Notch and scabrous genes. Our results suggest an alternative to the generally assumed mode of operation for lateral inhibition during development; more generally, they hint at a broader role for bistable switches in the initial establishment of patterns as well as in their maintenance.  相似文献   
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