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Parenteral nutrition (PN) provides support for patients lacking sufficient intestinal absorption of nutrients. Historically, the need for trace element (TE) supplementation was poorly appreciated, and multi-TE products were not initially subjected to rigorous oversight by the United States Food and Drug Administration (FDA). Subsequently, the American Society for Parenteral and Enteral Nutrition (ASPEN) issued dosage recommendations for PN, which are updated periodically. The FDA has implemented review and approval processes to ensure access to safer and more effective TE products. The development of a multi-TE product meeting ASPEN recommendations and FDA requirements is the result of a partnership between the FDA, industry, and clinicians with expertise in PN. This article examines the rationale for the development of TRALEMENT® (Trace Elements Injection 4*) and the FDA’s rigorous requirements leading to its review and approval. This combination product contains copper, manganese, selenium, and zinc and is indicated for use in adults and pediatric patients weighing ≥10 kg. Comprehensive management of PN therapy requires consideration of many factors when prescribing, reviewing, preparing, and administering PN, as well as monitoring the nutritional status of patients receiving PN. Understanding patients’ TE requirements and incorporating them into PN is an important part of contemporary PN therapy. 相似文献
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Esophageal diverticula are rare. The association of cancer and diverticula has been described. Some authors adopt a conservative non‐surgical approach in selected patients with diverticula whereas others treat the symptoms by diverticulopexy or myotomy only, leaving the diverticulum in situ. However, the risk of malignant degeneration should be may be taken in account if the diverticulum is not resected. The correct evaluation of the possible risk factors for malignancy may help in the decision making process. We performed a literature review of esophageal diverticula and cancer. The incidence of cancer in a diverticulum is 0.3–7, 1.8, and 0.6% for pharyngoesophageal, midesophageal, and epiphrenic diverticula, respectively. Symptoms may mimic those of the diverticulum or underlying motor disorder. Progressive dysphagia, unintentional weight loss, the presence of blood in the regurgitated material, regurgitation of peaces of the tumor, odynophagia, melena, hemathemesis, and hemoptysis are key symptoms. Risk factors for malignancy are old age, male gender, long‐standing history, and larger diverticula. A carcinoma may develop in treated diverticula, even after resection. Outcomes are usually quoted as dismal because of a delayed diagnosis but several cases of superficial carcinoma have been described. The treatment follows the same principals as the therapy for esophageal cancer; however, diverticulectomy is enough in cases of superficial carcinomas. Patients must be carefully evaluated before therapy and a long‐term follow‐up is advisable. 相似文献
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Stephanie Powell MA Ann Trotter MA Patti Thobro MA Robin Haas MSW 《Residential treatment for children & youth》2013,30(4):327-344
This study used a multimethod approach to evaluate the relationship of alexithymia (as measured by the 20-item Toronto Alexithymia Scale and the 30-item Emotion Awareness Questionnaire), psychosocial development (assessed with the Measure of Psychosocial Development), and risk behavior (as measured by the Youth Comprehensive Risk Assessment) in 67 adolescents (85% from rural communities) in a rural residential treatment facility. Results revealed that both measures of alexithymia demonstrated good internal consistency and convergent validity. The EAQ-30 demonstrated stronger convergent validity over the TAS-20 with psychosocial measures of shame, inferiority, and role confusion and was more robust in differentiating risk behavior among males and females. Adolescent females scored higher on measures of alexithymia than males and demonstrated significantly more shame, diminished bodily awareness, and risk to self; whereas, males demonstrated significantly more risk to others. Overall, this study contributes to the current literature of alexithymia, provides further support for the validity of the alexithymia construct with adolescents, and sheds light on the importance of emotional awareness and expression in adolescent psychosocial development. Although exploratory, this study also increases clinical understanding of how risk behavior develops and manifests differently in male and female adolescents, specifically with regard to shame and diminished bodily awareness. 相似文献
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Signal transduction by the platelet Fc receptor 总被引:6,自引:1,他引:6
We have evaluated the mechanism by which crosslinking human platelet Fc receptor (FcR) for IgG triggers platelet aggregation and the platelet release reaction. Platelet FcR was crosslinked by incubating purified human platelets with anti-FcRII monoclonal antibody and F(ab')2 anti- mouse Ig. The resultant [Ca2+]i increase, monitored by Fura-2 and measured in the absence of extracellular Ca2+, reached a peak of 750 +/- 50 nmol/L. The effects of cyclooxygenase inhibitors, aspirin and indomethacin, and a phospholipase A2 inhibitor, dibromoacetophenone, were examined. Regardless of the inhibitor, at least 25% of the [Ca2+]i increase remained. Thrombin (0.2 U/mL) stimulated an immediate [Ca2+]i increase that reached 1.95 +/- 0.8 mumol/L. The [Ca2+]i increase generated by thrombin was only slightly reduced by these inhibitors. Crosslinking the FcRII of platelets resulted in a fivefold increase in the production of [3H]inositol phosphates, (IP) which, in the absence of extracellular Ca2+ was insensitive to aspirin. The activation of a [Ca2+]i increase along with the measured increases in IP indicate that FcRII crosslinking leads to the activation of phospholipase C (PLC). In contrast to thrombin, platelet activation via FcRII depends to a large extent on arachidonic acid metabolites. However, neither cyclooxygenase nor phospholipase A2 inhibitors completely blocked FcRII-stimulated [Ca2+]i increase. These observations led us to propose that crosslinking of platelet FcRII initially activates PLC. 相似文献
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Mackewicz CE Yuan J Tran P Diaz L Mack E Selsted ME Levy JA 《AIDS (London, England)》2003,17(14):F23-F32
BACKGROUND: CD8 T cells from healthy HIV-infected individuals inhibit HIV replication in infected CD4 T cells by a non-cytotoxic mechanism mediated by a soluble CD8 cell antiviral factor, CAF. Recently, the antimicrobial peptides, alpha-defensins, were reported to constitute CAF. OBJECTIVE: To examine the antiviral activity of alpha-defensins and address their potential role in CD8 cell non-cytotoxic antiviral responses. DESIGN AND METHODS: A purified mixture of human neutrophil proteins (HNP) 1-3 (alpha-defensins) was used to examine the effect of alpha-defensins on HIV virions and on HIV replication in CD4 cells treated prior to or post infection. alpha-Defensin expression was analyzed at the RNA and protein level in CD8 cells as well as in various other cell types. Antibodies to the defensins were tested for their ability to inhibit CAF activity in CD8 cell culture fluids. RESULTS: The alpha-defensins exhibited anti-HIV activity on at least two levels: directly inactivating virus particles; and affecting the ability of target CD4 cells to replicate the virus. However, while we could demonstrate alpha-defensins in neutrophils and monocytes, we found no evidence for the production of these peptides by CD8 T cells. No messenger RNA encoding these proteins was detected in purified CD8 T cells, nor did these cells produce intracellular or extracellular alpha-defensin peptides. Moreover, antibodies specific for human alpha-defensins 1, 2, and 3 did not block the antiviral activity of CAF-active CD8 cell culture fluids. CONCLUSIONS: The alpha-defensins are not produced by CD8 cells but unexpectedly were found to be expressed in monocytes. alpha-Defensins can have anti-HIV activity but are not CD8 cell antiviral factors. 相似文献
28.
CL Sanchez CS Biskup S Herpertz TJ Gaber CM Kuhn SH Hood FD Zepf 《The international journal of neuropsychopharmacology / official scientific journal of the Collegium Internationale Neuropsychopharmacologicum (CINP)》2015,18(10)
The neurotransmitters serotonin and dopamine both have a critical role in the underlying neurobiology of different behaviors. With focus on the interplay between dopamine and serotonin, it has been proposed that dopamine biases behavior towards habitual responding, and with serotonin offsetting this phenomenon and directing the balance toward more flexible, goal-directed responding. The present focus paper stands in close relationship to the publication by Worbe et al. (2015), which deals with the effects of acute tryptophan depletion, a neurodietary physiological method to decrease central nervous serotonin synthesis in humans for a short period of time, on the balance between hypothetical goal-directed and habitual systems. In that research, acute tryptophan depletion challenge administration and a following short-term reduction in central nervous serotonin synthesis were associated with a shift of behavioral performance towards habitual responding, providing further evidence that central nervous serotonin function modulates the balance between goal-directed and stimulus-response habitual systems of behavioral control. In the present focus paper, we discuss the findings by Worbe and colleagues in light of animal experiments as well as clinical implications and discuss potential future avenues for related research. 相似文献
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Emanuele D’Amico Silvia Messina Cinzia Caserta Francesco Patti 《Expert opinion on drug safety》2015,14(7):1157-1168
Introduction: Daclizumab (DAC) is a mAb that binds to CD25, a receptor on the surface of lymphocytes for IL-2, a chemical messenger in the immune system. This prevents activation and proliferation of lymphocytes, which are involved in the immune attack in multiple sclerosis (MS).Areas covered: In this review, we will focus on newly emerging DAC-high-yield process (HYP) therapy for MS. Based on published original articles and citable meeting abstracts, we will discuss its mode of action as well as data on efficacy and safety.Expert opinion: DAC has been observed to have multiple (biological) effects, which may contribute to beneficial effects in immune-related disease and particularly in relapsing-remitting MS. The positive results in the clinical studies represent achievement of an important milestone in the development of DAC-HYP as a potential new treatment option for MS patients. The benefit/risk ratios of this new biological agent in MS therapy are still being evaluated. Soon, DAC-HYP might qualify as MS therapy. A safety monitoring program is recommended in the clinical practice. 相似文献
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