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41.

Objective

To assess whether dietary supplements that are herbal and/or animal-derived products, marketed for enhancing metabolism or promoting energy, “adrenal fatigue,” or “adrenal support,” contain thyroid or steroid hormones.

Methods

Twelve dietary adrenal support supplements were purchased. Pregnenolone, androstenedione, 17-hydroxyprogesterone, cortisol, cortisone, dehydroepiandrosterone sulfate, synthetic glucocorticoids (betamethasone, dexamethasone, fludrocortisone, megestrol acetate, methylprednisolone, prednisolone, prednisone, budesonide, and triamcinolone acetonide) levels were measured twice in samples in a blinded fashion. This study was conducted between February 1, 2016, and November 1, 2016.

Results

Among steroids, pregnenolone was the most common hormone in the samples. Budesonide, 17-hydroxyprogesterone, androstenedione, cortisol, and cortisone were the others in order of prevalence. All the supplements revealed a detectable amount of triiodothyronine (T3) (63-394.9?ng/tablet), 42% contained pregnenolone (66.12-205.2?ng/tablet), 25% contained budesonide (119.5-610 ng/tablet), 17% contained androstenedione (1.27-7.25 ng/tablet), 8% contained 17-OH progesterone (30.09 ng/tablet), 8% contained cortisone (79.66 ng/tablet), and 8% contained cortisol (138.5 ng/tablet). Per label recommended doses daily exposure was up to 1322 ng for T3, 1231.2 ng for pregnenolone, 1276.4 ng for budesonide, 29 ng for androstenedione, 60.18 ng for 17-OH progesterone, 277 ng for cortisol, and 159.32 ng for cortisone.

Conclusion

All the supplements studied contained a small amount of thyroid hormone and most contained at least 1 steroid hormone. This is the first study that measured thyroid and steroid hormones in over-the-counter dietary “adrenal support” supplements in the United States. These results may highlight potential risks of hidden ingredients in unregulated supplements.  相似文献   
42.
Thirty-nine previously untreated or minimally treated patients with squamous cell carcinoma of the head and neck were entered onto a chemoradiotherapy protocol employing multiple courses of simultaneous radiation therapy, cisplatin, and a 4-day 5-FU infusion. Thirty-eight patients were evaluable for response and toxicity. Twenty-three patients underwent surgical resection midway through this therapy and 11 (48%) were pathologically free of disease. Thirty-five of the 38 patients (92%) were ultimately rendered disease-free by this combined modality protocol. Thirty-one patients remain disease-free, with a projected 2-year disease-free survival of 74%. Although the treatment-associated mucositis and myelo-suppression were significant, this chemoradiotherapeutic approach is promising and merits further study.  相似文献   
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Sex steroid levels and steroid metabolism were investigated in relation to early gonadal development in a mixed sex population of the tilapia Oreochromis niloticus. Androstenedione (AD), testosterone (T), 11-ketotestosterone (KT), and estradiol (E2) were quantified by radioimmunoassay (RIA) of whole body extracts. Androstenedione metabolism was assessed by incubations in vitro with 3H-AD and metabolites were identified by thin-layer chromatography coupled with radioisotope image analysis. Histology revealed the presence of gonadal structures at 15 days postfertilization (dpf) and ovaries at 36 dpf, with other individuals exhibiting undifferentiated gonads containing germinal cells, presumably eventual testes. Androgen levels were initially high in eggs then decreased severalfold prior to the emergence of gonads. A transient increase in the levels of T and KT occurred at 22 dpf. Levels of E2 were either low or undetectable except for a transient increase (43 dpf) after ovaries were present. Levels of T approached bimodality from 57 to 64 dpf. Steroid metabolism generally increased throughout development. Metabolites were generally similar, consisting of T predominantly as well as 5beta-reduced androgen derivatives and 11-oyxgenated derivatives. Estriol was tentatively identified. Conjugated steroids were not formed. Two types of steroid metabolic profiles occurred at 50 dpf. These results demonstrate that changes in the steroidogenic profile occur during early transitions of gonadal development. Notably, (1) steroid biosynthetic capacity preceeds gonadal differentiation, (2) evidence for estrogens occurs after ovarian development has begun, and (3) bimodality of levels of T and differential steroid metabolism later in development may reflect the onset of sexual divergence.  相似文献   
45.
46.
A 63 year old woman with Ehlers-Danlos syndrome and a malabsorption syndrome secondary to bacterial overgrowth in a megaduodenum is described. To our knowledge this is the first report of either a megaduodenum or a malabsorption state in association with the Ehlers-Danlos syndrome.  相似文献   
47.
ObjectivesDalbavancin is a lipoglycopeptide active against methicillin-resistant Staphylococcus aureus (MRSA). Its long half-life (8.5–16 days) allows for once-weekly or single-dose treatments but could prolong the mutant selection window, promoting resistance and cross-resistance to related antimicrobials such as vancomycin. The objective of this study was to evaluate the capacity of post-distributional pharmacokinetic exposures of dalbavancin to select for resistance and cross-resistance in MRSA.MethodsWe simulated average, post-distributional exposures of single-dose (1500 mg) dalbavancin (fCmax 9.9 μg/mL, β-elimination t1/2 204 h) in an in vitro pharmacokinetic/pharmacodynamic (PK/PD) model for 28 days (672 h) against five MRSA strains and one methicillin-susceptible strain (MSSA). Samples were collected at least daily, and surviving colonies were enumerated and screened for resistance on drug-free and dalbavancin-supplemented medium respectively. Isolates from resistance screening plates were subjected to whole-genome sequencing (WGS) and susceptibly testing against dalbavancin, vancomycin, daptomycin, and six β-lactams with varying penicillin-binding protein (PBP) affinities.ResultsDalbavancin was bactericidal against most strains for days 1–4 before regrowth of less susceptible subpopulations occurred. Isolates with eight-fold increases in dalbavancin MIC were detected as early as day 4 but increased 64–128-fold in all models by day 28. Vancomycin and daptomycin MICs increased 4–16-fold, exceeding the susceptibly breakpoints for both antibiotics; β-lactam MICs generally decreased by two-to eight-fold, suggesting a dalbavancin–β-lactam seesaw effect, but increased by eight-fold or more in certain isolates. Resistant isolates carried mutations in a variety of genes, most commonly walKR, apt, stp1, and atl.ConclusionsIn our in vitro system, post-distributional dalbavancin exposures selected for stable mutants with reduced susceptibility to dalbavancin, vancomycin, and daptomycin, and generally increased susceptibility to β-lactams in all strains of MRSA tested. The clinical significance of these findings remains unclear, but created an opportunity to genotype a unique collection of dalbavancin-resistant strains for the first time. Mutations involved genes previously associated with vancomycin intermediate susceptibility and daptomycin non-susceptibility, most commonly walKR-associated genes.  相似文献   
48.
49.
50.

Objectives

An epoxy resin worker developed hypersensitivity pneumonitis requiring lung transplantation and had an abnormal blood lymphocyte proliferation test (LPT) to an epoxy hardener. We assessed the prevalence of symptoms, abnormal spirometry, and abnormal epoxy resin LPT results in epoxy resin workers compared to unexposed workers.

Methods

Participants completed questionnaires and underwent spirometry. We collected blood for epoxy resin LPT and calculated stimulation indices for five epoxy resin products.

Results

We compared 38 exposed to 32 unexposed workers. Higher exposed workers were more likely to report cough (OR 10.86, [1.23‐infinity], p = 0.030) or wheeze (OR 4.44, [1.00‐22.25], p = 0.049) than unexposed workers, even controlling for smoking. Higher exposed workers were more likely to have abnormal FEV1 than unexposed workers (OR 10.51, [0.86‐589.9], p = 0.071), although not statistically significant when adjusted for smoking. There were no differences in proportion of abnormal epoxy resin system LPTs between exposed and unexposed workers.

Conclusions

In summary, workers exposed to epoxy resin system chemicals were more likely to report respiratory symptoms and have abnormal FEV1 than unexposed workers. Use of epoxy resin LPT was not helpful as a biomarker of exposure and sensitization.  相似文献   
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