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591.
A majority of the novel orally administered, molecularly targeted anticancer therapies are weak bases that exhibit pH-dependent solubility, and suppression of gastric acidity with acid-reducing agents could impair their absorption. In addition, a majority of cancer patients frequently take acid-reducing agents to alleviate symptoms of gastroesophageal reflux disease, thereby raising the potential for a common but underappreciated drug-drug interaction (DDI) that could decrease the exposure of anticancer medication and result in subsequent failure of therapy. This article is a review of the available clinical literature describing the extent of the interaction between 15 orally administered, small-molecule targeted anticancer therapies and acid-reducing agents. The currently available clinical data suggest that the magnitude of this DDI is largest for compounds whose in vitro solubility varies over the pH range 1-4. This range represents the normal physiological gastric acidity (pH ~1) and gastric acidity while on an acid-reducing agent (pH ~4).  相似文献   
592.
Cytomegalovirus (CMV) reactivation occurs frequently in critically ill patients. The natural course of CMV infection and the interaction between CMV and the adaptive immune system in this setting remain poorly defined. Fifty‐three CMV‐seropositive patients in a surgical and trauma intensive care unit were included in this study. The CMV DNA load in tracheal aspirates (TA) and plasma (PL) was monitored by qPCR. CMV‐specific T‐cell immunity was assessed by intracellular cytokine staining. Plasma TNF‐α levels were determined by ELISA. CMV reactivation occurred in 39.7% of patients (23% had CMV DNA detected only in TA). The analysis of TA allowed an earlier diagnosis in 28% of patients. Clearance of CMV DNAemia preceded that of CMV DNA in TA in some episodes. Peak CMV DNA levels were significantly higher in TA than in PL (P = 0.02). CMV reactivation developed in the presence of CMV‐specific T cells. Termination of CMV reactivation was associated with an expansion of functional CMV‐specific T cells. Plasma levels of TNF‐α did not allow for the prediction of the occurrence of CMV reactivation. CMV‐specific T‐cell immunity is preserved in most critically ill patients experiencing CMV reactivation. Analysis of respiratory specimens is imperative for an optimal monitoring of CMV reactivation in this setting. J. Med. Virol. 82:1384–1391, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
593.
Diploid spermatozoa represent 0.2-0.3% of all spermatozoa in the normal population and cause 8.3% of diandric triploids. Errors in meiosis I and II are the most common mechanisms by which diploid spermatozoa are produced. Endoreduplication before meiosis has been suggested as a possible origin for tetraploid meiocytes, which might, in turn, produce diploid sperm. Synaptonemal complex (SC) spreads of a fertile man were immunolabelled (SCP3, MLH1 and CENP) and hybridized with subtelomere-specific multiplex fluorescent in situ hybridization (stM-FISH) assay for SCs identification. The unexpected finding of a tetraploid pachytene cell and the identification of all of its SCs demonstrate that synapsis and crossover events can occur in human tetraploid cells. Moreover, it indicates that diploid sperm may also originate from mitotic errors (endoreduplication) occurring before meiosis.  相似文献   
594.
Objective: To find out the efficacy of zinc supplementation in decreasing the levels of serum calprotectin and inflammatory cytokines with improvement in outcome in neonatal sepsis.

Methods: Neonates with clinical signs suggestive of sepsis and at least two screening tests positive were randomized into two groups – zinc group and control group. The zinc group received 3?mg/kg of zinc sulfate monohydrate twice a day orally for 10 days along with antibiotics. The control group received antibiotics and supportive care. Serum zinc, calprotectin, TNF-α and IL-6 were estimated in serum at recruitment and 10 days later after completion of antibiotics. The babies were monitored daily till discharge and mortality rate was compared between the groups.

Results: Baseline characteristics were similar between the groups. Serum zinc levels were considerably increased in the zinc group after supplementation. There was significant decline in concentrations of serum calprotectin, TNF-α and IL-6 (p?p?p=?0.12.

Conclusion: Neonates with sepsis who received zinc in addition to antibiotics showed significant reduction in serum calprotectin and inflammatory cytokines. Although mortality was lower in zinc group, it was not statistically significant.  相似文献   
595.
596.
Mechanisms of the Development of Allergy (MeDALL), a Seventh Framework Program European Union project, aims to generate novel knowledge on the mechanisms of initiation of allergy. Precise phenotypes of IgE-mediated allergic diseases will be defined in MeDALL. As part of MeDALL, a scientific seminar was held on January 24, 2011, to review current knowledge on the IgE-related phenotypes and to explore how a multidisciplinary effort could result in a new integrative translational approach. This article provides a summary of the meeting. It develops challenges in IgE-related phenotypes and new clinical and epidemiologic approaches to the investigation of allergic phenotypes, including cluster analysis, scale-free models, candidate biomarkers, and IgE microarrays; the particular case of severe asthma was reviewed. Then novel approaches to the IgE-associated phenotypes are reviewed from the individual mechanisms to the systems, including epigenetics, human in?vitro immunology, systems biology, and animal models. The last chapter deals with the understanding of the population-based IgE-associated phenotypes in children and adolescents, including age effect in terms of maturation, observed effects of early-life exposures and shift of focus from early life to pregnancy, gene-environment interactions, cohort effects, and time trends in patients with allergic diseases. This review helps to define phenotypes of allergic diseases in MeDALL.  相似文献   
597.
This study aimed to determine the aetiology of community-acquired pneumonia (CAP) by adding polymerase chain reaction (PCR) to conventional methods and to describe the clinical and laboratory features between patients with bacterial pneumonia (BP) and viral pneumonia (VP). Adults with CAP admitted from November 2009 to October 2010 were included. Demographics, comorbidities, severity and clinical features were recorded. Conventional microbiological methods included blood and sputum cultures, acute and convalescent serologic samples, and antigen urinary detection. New methods included multiplex PCR for Mycoplasma pneumoniae, Legionella pneumophila, Chlamydophila pneumoniae, Bordetella pertussis and 15 respiratory viruses. A total of 169 patients were included. Using conventional methods, we identified a pathogen in 51?% of cases. With PCR, up to 70?% of cases had an aetiological diagnosis. Forty-five patients had BP (34?%), 22 had VP (17?%) and 25 (19?%) had co-infection (BP and VP). Pneumococci and respiratory syncytial virus (RSV) were the most frequently identified pathogens. Procalcitonin (PCT) and C-reactive protein (CRP) median values were significantly higher in BP than in VP patients. Shaking chills, higher CURB score and shock were significantly more frequent in BP. A viral infection was identified in more than one-third of patients with CAP. Clinical and laboratory features could help to differentiate between VP and BP and to guide empirical therapy.  相似文献   
598.
BACKGROUND: Anomalies in meiotic prophase I have been related to partial or total meiotic arrest. These anomalies include an abnormal synaptic process, resulting in disorders in meiotic recombination. METHODS: In the present study, we analyse primary spermatocytes from 12 infertile men (four with non-obstructive azoospermia, six with oligoastenoteratozoospermia, one with astenoteratozoospermia and one normozoospermic) and five control fertile donors using immunocytological techniques for synaptonemal complex, meiotic recombination and centromeric proteins. RESULTS: Mean numbers of MLH1 foci per cell, frequencies of cells presenting an MLH1 focus in the XY pair and percentages of cells affected by abnormal synaptic patterns (gaps and splits) are reported for each of the infertile patients and control men. A positive correlation between the frequency of cells showing a recombination focus in the XY pair and the number of autosomal recombination foci per cell is found. CONCLUSIONS: Reduced recombination in the XY pair and an increased number of cells affected by gaps may explain some idiopathic male infertility cases. The results suggest that recombination in the XY pair could be an indicator for general recombination frequency and for a successful meiotic process.  相似文献   
599.
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