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101.

Background

Despite the introduction of direct-acting antiviral agents for chronic hepatitis C virus (HCV) infection, peginterferon alfa/ribavirin remains relevant in many resource-constrained settings. The non-randomized GUARD-C cohort investigated baseline predictors of safety-related dose reductions or discontinuations (sr-RD) and their impact on sustained virologic response (SVR) in patients receiving peginterferon alfa/ribavirin in routine practice.

Methods

A total of 3181 HCV-mono-infected treatment-naive patients were assigned to 24 or 48 weeks of peginterferon alfa/ribavirin by their physician. Patients were categorized by time-to-first sr-RD (Week 4/12). Detailed analyses of the impact of sr-RD on SVR24 (HCV RNA <50 IU/mL) were conducted in 951 Caucasian, noncirrhotic genotype (G)1 patients assigned to peginterferon alfa-2a/ribavirin for 48 weeks. The probability of SVR24 was identified by a baseline scoring system (range: 0–9 points) on which scores of 5 to 9 and <5 represent high and low probability of SVR24, respectively.

Results

SVR24 rates were 46.1% (754/1634), 77.1% (279/362), 68.0% (514/756), and 51.3% (203/396), respectively, in G1, 2, 3, and 4 patients. Overall, 16.9% and 21.8% patients experienced ≥1 sr-RD for peginterferon alfa and ribavirin, respectively. Among Caucasian noncirrhotic G1 patients: female sex, lower body mass index, pre-existing cardiovascular/pulmonary disease, and low hematological indices were prognostic factors of sr-RD; SVR24 was lower in patients with ≥1 vs. no sr-RD by Week 4 (37.9% vs. 54.4%; P = 0.0046) and Week 12 (41.7% vs. 55.3%; P = 0.0016); sr-RD by Week 4/12 significantly reduced SVR24 in patients with scores <5 but not ≥5.

Conclusions

In conclusion, sr-RD to peginterferon alfa-2a/ribavirin significantly impacts on SVR24 rates in treatment-naive G1 noncirrhotic Caucasian patients. Baseline characteristics can help select patients with a high probability of SVR24 and a low probability of sr-RD with peginterferon alfa-2a/ribavirin.  相似文献   
102.
Suspension cultures of Papaver bracteatum Arya II Lindl., grown without hormone in the presence of conidial extracts of Verticillium dahliae Kleb., accumulate millimolar quantities of the benzophenanthridine alkaloid, sanguinarine. Under the fluorescence microscope, the elicitor-treated cells display an orange-yellow fluorescence characteristic of sanguinarine, primarily near the periphery of the cells. Electron-microscopic inspection showed the presence of slightly dilated endoplasmic reticulum and of electron-dense protuberances on the tonoplast of large central vacuoles. These osmiophilic aggregates lining the tonoplast bud into spherical bodies, appear to become detached from the membrane and are released into the vacuole. Upon subcellular fractionation of elicited cells on Renografin step gradients, sanguinarine was found to be distributed in all bands but with 86% concentrated in the gradient pellet. Analysis of the pellet by electron microscopy showed that it contained electron-dense fragments similar to the osmiophilic bodies observed on the tonoplast of intact elicited cells. In elicited cell cultures, most of the sanguinarine was recovered from medium in a 100·g sedimenting, cell-free, particulate fraction accounting for as much as 85% of the media sanguinarine and 62% of the total sanguinarine. The sanguinarine-rich 100·g media pellet was determined to be two-thirds protein, one-third RNA and was essentially devoid of phenolics, phospholipid and DNA. The pellet consisted of electrondense material and cytoplasmic remnants resembling those found in the Renografin pellet and tonoplast aggregates of intact cells. When placed under hypotonic conditions or extracted with aqueous buffer, pH 3–11, the pellet did not release sanguinarine. These observations provide evidence for storage of sanguinarine at electron-dense deposits which occur on the tonoplast and as freely floating bodies in vacuoles.Abbreviations BA N6-benzyladenine - 2,4-D 2,4-dichlorophenoxyacetic acid - EM electron microscopy - ER endoplasmic reticulum - HPLC high-pressure liquid chromatography - MRST Murashige and Skoog's revised tobacco medium  相似文献   
103.
Interleukin 1 (IL-1) is a major soluble mediator of inflammation. Two human IL-1 genes, alpha and beta, have been isolated, which encode polypeptides with only 20-30% amino acid sequence homology. Unlike most secreted proteins, the two cytokines do not have a signal sequence, an unexpected finding in view of their biological role. Here we show that IL-1 beta is actively secreted by activated human monocytes via a pathway of secretion different from the classical endoplasmic reticulum--Golgi route. Drugs which block the intracellular transport of IL-6, of tumour necrosis factor alpha and of other secretory proteins do not inhibit secretion of IL-1 beta. Secretion of IL-1 beta is blocked by methylamine, low temperature or serum free medium, and is increased by raising the culture temperature to 42 degrees C or by the presence of calcium ionophores, brefeldin A, monensin, dinitrophenol or carbonyl cyanide chlorophenylhydrazone. IL-1 beta is contained in part within intracellular vesicles which protect it from protease digestion. In U937 cells large amounts of IL-1 beta are made but none is secreted. In these cells IL-1 beta is not found in the vesicular fraction, and all the protein is accessible to protease digestion. This suggests that intracellular vesicles that contain IL-1 beta are part of the protein secretory pathway. We conclude that IL-1 beta is released by activated monocytes via a novel mechanism of secretion which may involve translocation of intracellular membranes and is increased by stress conditions.  相似文献   
104.
Doubly-labeled [3H, 14C]tyrosines, [1-13C-]tyramine or [2-14C]tyramine, administered to the stems of intact Papaver somniferum L. plants, were found to be incorporated into the morphinan alkaloids of the plant with comparable efficiency. 3H/14C ratios of alkaloids from plants fed the tyrosines were consistent with an almost equal conversion of this amino acid into the tetrahydroisoquinoline (TIQ) and benzyl-derived segments. Nuclear magnetic resonance (NMR) analyses of morphine isolated after administration of [1-13C]tyramine demonstrated selective labeling of C-16 of the alkaloid, indicating the conversion of this amine primarily into the TIQ-derived moiety. Morphine and thebaine labeled by [2-14C]tyramine were degraded to phenanthridines and N,N-dimethyl ethylamines. Of the total radioactivity in the alkaloids 97% was found to be associated with the ethylamines, a distribution consistent with the NMR data. This preferential utilization of tyramine in the biosynthesis of morphinan alkaloids can be explained by the compartmentalization of intermediates and enzymes of the pathway.Abbreviations L-dopa L-3,4-dihydroxyphenylalanine - HPLC high-pressure liquid chromatography - NMR nuelear magnetic resonance - TIQ tetrahydroisoquinoline  相似文献   
105.
Obese people tend to have low zinc circulation levels; this is not always related to zinc intake but can reflect the distribution of zinc in relation to the proportion of body fat and factors related to the inflammatory processes that cause obesity. The purpose of this study was to assess zinc distribution in 15 obese adolescent girls before and after a nutritional orientation program. Participants ranged from 14 to 18 years old (postpubescent) and had a body fat percent (BF%) of >35 %. Zinc nutritional status and other zinc-dependent parameters, such as superoxide dismutase (SOD) and insulin levels, were assessed by biochemical analysis of plasma and erythrocytes, salivary sediment, and urine. Samples were collected before and after 4 months of dietary intervention. Dual energy X-ray absorptiometry (DXA) was used to verify BF% both at the beginning and at the end of the study. Food consumption was assessed in ten individual food questionnaires throughout the study; food groups were separated on the questionnaires in the same way as suggested by some authors to develop the Healthy Eating Index (HEI) but with the addition of zinc. After 4 months of nutritional orientation, 78 % of the participants showed a decrease in BF%. Intraerythrocytic zinc increased over the study period, while salivary sediment zinc, SOD, insulin, and Zn urinary24 h/creatinine all decreased (p?<?0.05). There was no difference in zinc intake throughout the study but participants did increase their consumption of fruits, dairy, and meats during the study (p?<?0.05). There were inverse and statistically significant correlations between the increased levels of intraerythrocytic zinc and decreased levels of SOD. There was also a statistically significant correlation between BF% and Zn urinary 24h/creatinine, and SOD. All these parameters were diminished at the end of the study. The dietary intervention for obese adolescent girls is effective with decrease of BF that led to the redistribution of zinc in the body as shown by the changes in erythrocytes, plasma, salivary, urine zinc, as well as the complementary parameters of insulin and SOD. These changes were not affected by zinc intake.  相似文献   
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109.
The range of pathologies that lymph node (LN) fine needle cytology (FNC) may encounter is extremely wide and ancillary techniques, in addition to traditional smears, are generally required to reach reliable cytologic diagnoses. Storing part of the cytologic material may be useful or necessary for molecular testing. The main difficulties concern the generally small size of the sample and the different methods of acquisition of LN‐FNC. Therefore, the preanalytic phase is extremely important for LN‐FNC. This article outlines the management of LN‐FNC material, vials, technical devices (e.g.: additional smears, cytospin slides, LBC slides, cards, resins, etc.) and main ancillary techniques to assess their optimal application, taking into account the different diagnostic needs and cell storage.  相似文献   
110.
The 2016 World Health Organisation revised classification of lymphoma has sub‐classified well‐defined entities and added a number of provisional entities on the basis of new knowledge on genetic, epigenetics and phenotypical data; prognostic and predictive features are also part of this classification. New knowledge on well‐defined entities further enlightens the mechanisms of lymphomagenesis, which are more complex and multifactorial than once believed. Therapies are also more complex because traditional clinical trials have been integrated with new drugs and compounds with unique mechanisms of actions against distinct molecular targets. As lymphoma acquires additional genetic and phenotypic features over the time, pathological assessment is also necessary. Histological evaluation and tissue collection by surgical biopsies are necessary for phenotypical and molecular purposes; however, these are demanding procedures for both the patient and the health care system. At the same time, the choice of the best treatment for a specific entity, in different phases and different patients requires information that may not be available when the biopsy is performed. Fine needle aspiration cytology (FNAC) is successfully used in lymph nodes (LNs) in combination with different ancillary techniques and might be used to assess the phenotypic and genetic profile of specific targets and to get key information for therapy, in different phases and stages of the disease, with the option to re‐check the same target over time, without surgical excision. This brief review describes LN‐FNAC diagnostic criteria, current therapies for lymphomas and the potential role of LN‐FNAC in selecting non‐Hodgkin lymphomas patients for specific targeted treatments.  相似文献   
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