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61.
In 1994, naltrexone became the first medication approved by the Food and Drug Administration as an adjunct in alcoholism treatment in almost fifty years. Despite evidence of its efficacy, use of naltrexone is not widespread. Patient and physician focus groups were used to identify reasons naltrexone has not been prescribed more widely. Barriers to its widespread use include a lack of awareness, a lack of evidence of efficacy in practice, side effects, time for patient management, a reluctance to take medications, medication addiction concerns, Alcoholics Anonymous (AA) philosophy, and price. The study indicates that medications to treat alcoholism must overcome numerous barriers before becoming widely accepted.  相似文献   
62.
Social exploitation of vitellogenin   总被引:13,自引:0,他引:13       下载免费PDF全文
Vitellogenin is a female-specific glucolipoprotein yolk precursor produced by all oviparous animals. Vitellogenin expression is under hormonal control, and the protein is generally synthesized directly before yolk deposition. In the honeybee (Apis mellifera), vitellogenin is not only synthesized by the reproductive queen, but also by the functionally sterile workers. In summer, the worker population consists of a hive bee group performing a multitude of tasks including nursing inside the nest, and a forager group specialized in collecting nectar, pollen, water, and propolis. Vitellogenin is synthesized in large quantities by hive bees. When hive bees develop into foragers, their juvenile hormone titers increase, and this causes cessation of their vitellogenin production. This inverse relationship between vitellogenin synthesis and juvenile hormone is opposite to the norm in insects, and the underlying proximate processes and life-history reasons are still not understood. Here we document an alternative use of vitellogenin by showing that it is a source for the proteinaceous royal jelly that is produced by the hive bees. Hive bees use the jelly to feed larvae, queen, workers, and drones. This finding suggests that the evolution of a brood-rearing worker class and a specialized forager class in an advanced eusocial insect society has been directed by an alternative utilization of yolk protein.  相似文献   
63.
 Interferon (IFN)-α, a known inhibitor of myelopoiesis, is increasingly used to treat patients with systemic mastocytosis (SM). However, the mechanisms of IFN-α effects on mast cell (MC) growth remain unknown, and the treatment responses may be variable. In the present study, factor-dependent ex vivo differentiation of MCs from peripheral blood mononuclear cells (PBMNCs) was analyzed in a patient with SM treated with IFN-α2b (3 million U/day). The patient exhibited an extensive MC infiltration in his bone marrow (BM) and increasing serum total tryptase levels (spiking to >1400 ng/ml). PBMNCs were collected before and during IFN-α2b treatment and cultured in the presence or absence of stem cell factor (SCF, 100 ng/ml) for 42 days. In the absence of SCF, no MC growth was detectable. However, in the presence of SCF, MC containing tryptase appeared in the cultures. Treatment with IFN-α2b resulted in a time-dependent decrease in SCF-inducible formation of MCs from PB progenitor cells in vitro. Also, during IFN-α2b treatment, blood histamine concentrations decreased. Serum total tryptase levels initially increased despite IFN-α2b treatment. However, after a latency period of a few months, tryptase concentrations declined and then reached a plateau. In healthy individuals, the SCF-induced in vitro growth of MCs from their progenitor cells was also inhibitable by the addition of IFN-α2b. In summary, our data show that IFN-α2b can exhibit inhibitory effects on factor-dependent growth of MC progenitor cells. However, it still remains open which of the patients with mastocytosis can benefit from long-term IFN-α treatment. Received: 19 January 2000 / Accepted: 17 April 2000  相似文献   
64.
Idiopathic myointimal hyperplasia of mesenteric veins (IMHMV) is a rare and poorly understood disease that occurs in the rectosigmoid colon of predominantly young, previously healthy male patients. IMHMV typically requires segmental resection due to complications after a relatively protracted clinical course. This disease presents a challenging diagnostic dilemma for the clinician because it is initially often confused with chronic idiopathic inflammatory bowel disease. We report a case of IMHMV, illustrate endoscopic and histopathologic features, and review key characteristics of this rare entity.  相似文献   
65.
BACKGROUND & AIMS: Serotonin (5-HT) is a critical signaling molecule in the gut. 5-HT released from enterochromaffin cells initiates peristaltic, secretory, vasodilatory, vagal, and nociceptive reflexes. Despite being pathophysiologically divergent, ulcerative colitis (UC) and irritable bowel syndrome (IBS) are both associated with clinical symptoms that include alterations in the normal patterns of motility, secretion, and sensation. Our aim was to test whether enteric 5-HT signaling is defective in these disorders. METHODS: Rectal biopsy specimens were obtained from healthy controls and patients with UC, IBS with diarrhea (IBS-D), and IBS with constipation (IBS-C). Key elements of 5-HT signaling, including measures of 5-HT content, release, and reuptake, were analyzed with these samples. RESULTS: Mucosal 5-HT, tryptophan hydroxylase 1 messenger RNA, serotonin transporter messenger RNA, and serotonin transporter immunoreactivity were all significantly reduced in UC, IBS-C, and IBS-D. The enterochromaffin cell population was decreased in severe UC samples but was unchanged in IBS-C and IBS-D. When 5-HT release was investigated under basal and mechanical stimulation conditions, no changes were detected in any of the groups relative to controls. CONCLUSIONS: These data show that UC and IBS are associated with similar molecular changes in serotonergic signaling mechanisms. While UC and IBS have distinct pathophysiologic properties, these data suggest that shared defects in 5-HT signaling may underlie the altered motility, secretion, and sensation. These findings represent the first demonstration of significant molecular alterations specific to the gut in patients with IBS and support the assertion that disordered gastrointestinal function in IBS involves changes intrinsic to the bowel.  相似文献   
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68.
AnaConDa-100 ml (ACD-100, Sedana Medical, Uppsala, Sweden) is well established for inhalation sedation in the intensive care unit. But because of its large dead space, the system can retain carbon dioxide (CO2) and increase ventilatory demands. We therefore evaluated whether AnaConDa-50 ml (ACD-50), a device with half the internal volume, reduces CO2 retention and ventilatory demands during sedation of invasively ventilated, critically ill patients. Ten patients participated in this cross-over protocol. After sedation with isoflurane via ACD-100 for 24 h, the 5-h observation period started. During the first hour, ACD-100 was used; for the next 2 h, ACD-50; and for the last 2 h, ACD-100 was used again. Sedation was titrated to Richmond Agitation and Sedation Scale (RASS) score ??3 to ??4 and a processed electroencephalogram (Narcotrend Index, Narcotrend-Gruppe, Hannover, Germany) was recorded. Minute ventilation, CO2 elimination, and isoflurane consumption were compared. All patients were deeply sedated (Narcotrend Index, mean?±?SD: 38?±?10; RASS scores ??3 to ??5) and breathed spontaneously with pressure support throughout the observation period. Infusion rates of isoflurane and opioid, either remifentanil or sufentanil, as well as ventilator settings were unchanged. Minute ventilation and end-tidal CO2 were significantly reduced with the ACD-50, respiratory rate remained unchanged, and tidal volume decreased by 66?±?43 ml. End-tidal isoflurane concentrations were also slightly reduced while haemodynamic measures remained constant. The ACD-50 reduces the tidal volume needed to eliminate carbon dioxide without augmenting isoflurane consumption.  相似文献   
69.
Headaches are a frequent health problem among children and adolescents. The ocurrence of headaches and the resulting impairments in the quality of life and activities of daily living are modulated by biopsychosocial interactions, which necessitate a complex treatment program. The Dresden Childrens Headache Program (DreKiP) is a multidisciplinary therapy program consisting of eight modules for children and adolescents: education, stress relief, relaxation techniques, physical fitness, climbing therapy, art therapy and sensory training. In addition, there are six modules containing parallel workshops for parents. This outpatient program lasts 2–3 months and is performed parallel to the daily and school routine. Therapy groups consist of 6–8 patients in each age group. In total patients receive 15?h and the parents 7?h of therapy. Concomitant with the program, headache-associated data, such as headache frequency, medication use and school absence are documented. So far 32 children and adolescents in groups of 11, 14–15, 14–16, 17 and 17–18 years old completed the program. Of the 32 patients 19 presented with migraine and tension type headache, 6/32 with migraine and 7/32 with tension type headache only. The median number of headache days was 15 per month and 4 official school absence days per month. Preliminary results 6 months after the end of the therapy program showed reduced frequency of headaches in three quarters of our patients. The headache frequency was reduced from an initial median of 15 days per month to a median of 8 days per month after the program. The multidisciplinary program DreKiP improves the use of therapeutic means in children and adolescents with primary headaches. Children and adolescents with headache-related impairment in activities of daily life in school and leisure times constitute the target group of this therapy.  相似文献   
70.

Aim

Despite promising preclinical findings regarding clinical utility of farnesyltransferase inhibitors (FTI), such as lonafarnib, success of clinical trials is limited. A multicentre AGO-OVAR-15 phase II trial reported an unfavourable effect of lonafarnib on the outcome of patients with advanced ovarian cancer. This study was performed as a genetic subgroup analysis of the AGO-OVAR-15 trial, and investigated the utility of the promoter polymorphism rs11623866 of the farnesyltransferase ß-subunit gene (FNTB) in predicting the clinical effectiveness of lonafarnib.

Methods

The influence of rs11623866 (c.-609G > C) on FNTB promoter activity was investigated by electrophoretic-mobility-shift assay, luciferase-reporter assay and RT-qPCR. A total of 57 out of 105 patients from the AGO-OVAR-15 trial, treated with carboplatin and paclitaxel ± lonafarnib, was genotyped for rs11623866 by restriction fragment length polymorphism analysis. Genotype-dependent survival analysis was performed by Kaplan–Meier analysis.

Results

The presence of the G allele was associated with increased FNTB promoter activity compared with the C allele. An unfavourable effect of lonafarnib was limited to patients carrying a GG genotype (HRPFS 6.2, 95%CI = 2.01, 19.41, P = 0.002; HROS 9.6, 95%CI = 1.89, 48.54, P = 0.006). Median progression free survival (PFS) for patients with the GG genotype in the lonafarnib treated arm was 10 months, whereas median PFS without FTI-treatment was 40 months. Median overall survival (OS) in the lonafarnib-treated group was 19 months, whereas median OS was not reached in the untreated group.

Conclusions

Discrepancies between preclinical success and clinical failure may be due to the patients'' genetic variability of FNTB. Therefore, our results may encourage retrospective evaluation of FNTB polymorphisms in previous FTI studies, especially those reporting positive FTI response.  相似文献   
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