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1.

Objective

Helicobacter pylori infection is common among Asians. However, evidence in the recent years has demonstrated a decrease in the prevalence of H. pylori infection among children and adults worldwide. Our aim was to update its prevalence in symptomatic children in our locality in the recent 12?years and compared to the results of our previous review published in 2005.

Methods

A retrospective review was carried out between 2005 and 2017. All children who presented with dyspepsia or gastrointestinal bleeding and underwent oesophagogastroduodenoscopy with antral biopsy taken were included. Patient demographics, endoscopic, or histological diagnosis and the H. pylori status were recorded.

Main Results

A total of 602 patients were included. There was a statistically significant decreasing trend of H. pylori infection rate between 2005 and 2017 (p?=?0.003). The overall infection rate from this study was 12.8%, compared to 25.6% from our previous review. Overall failure of eradication with first-line antibiotic therapy has increased to 29.3% from 10% in our previous review.

Conclusion

There was a decrease in the prevalence of H. pylori infection among symptomatic children for the recent 12?years, comparing to our previous data from 2005. We hypothesize that the reduction in prevalence of H. pylori infection among adults and the decrease in the practice of sharing chopsticks during meals have led to a decrease in transmission of the bacteria among family members in Hong Kong. However, the failure of eradication with first line treatment was higher, possibly due to the increase in antibiotics usage and resistance.

Level of Evidence

III  相似文献   
2.
3.

Introduction

There is an urgent need for new anti-tuberculosis (TB) drugs and optimization of current TB treatment. Moxifloxacin and linezolid are valuable options for the treatment of drug-resistant TB; however, it is crucial to find a dose at which these drugs not only show high efficacy but also suppress the development of further drug resistance.

Methods

Activity of moxifloxacin and linezolid against Mycobacterium tuberculosis was studied in the hollow-fiber infection model system in log-phase growth under neutral pH and slow growth in an acidic environment. Doses that achieved maximum bacterial kill while suppressing the emergence of drug resistance were determined. Through Monte Carlo simulations the quantitative output of this in vitro study was bridged to the human patient population to inform optimal dosage regimens while accounting for clinical minimum inhibitory concentration (MIC) distributions.

Results and Discussion

Moxifloxacin activity was significantly decreased in an acidified environment. The loss of activity was compensated by accumulation of the drug in TB lung lesions; therefore, moderate efficacy can be expected. Moxifloxacin 800 mg/day is the dose that most likely leads to resistance suppression while exerting maximum bacterial kill. Linezolid demonstrated very good activity even at a reduced pH. Linezolid 900 mg once-daily (QD) is likely to achieve a maximum killing effect and prevent the emergence of drug resistance; 600 mg QD in a robust drug regimen may have similar potential.  相似文献   
4.
5.

Background

Malnutrition is a significant problem for hospitalized patients. However, the true prevalence of reported malnutrition diagnosis in real-world clinical practice is largely unknown. Using a large collaborative multi-institutional database, the rate of malnutrition diagnosis was assessed and used to assess institutional variables associated with higher rates of malnutrition diagnosis.

Objective

The aim of this study was to define the prevalence of malnutrition diagnosis reported among inpatient hospitalizations.

Design

The University Health System Consortium (Vizient) database was retrospectively reviewed for reported rates of malnutrition diagnosis.

Participants/setting

All adult inpatient hospitalization at 105 member institutions during fiscal years 2014 and 2015 were evaluated.

Main outcome measures

Malnutrition diagnosis based on the presence of an International Classification of Diseases-Ninth Revision diagnosis code.

Statistical analysis

Hospital volume and publicly available hospital rankings and patient satisfaction scores were obtained. Multiple regression analysis was performed to assess the association between these variables and reported rates of malnutrition.

Results

A total of 5,896,792 hospitalizations were identified from 105 institutions during the 2-year period. It was found that 292,754 patients (5.0%) had a malnutrition diagnosis during their hospital stay. By institution, median rate of malnutrition diagnosis during hospitalization was 4.0%, whereas the rate of severe malnutrition diagnosis was 0.9%. There was a statistically significant increase in malnutrition diagnosis from 4.0% to 4.9% between 2014 and 2015 (P<0.01). Institutional factors associated with increased diagnosis of malnutrition were higher hospital volume, hospital ranking, and patient satisfaction scores (P<0.01).

Conclusions

Missing a malnutrition diagnosis appears to be a universal issue because the rate of malnutrition diagnosis was consistently low across academic medical centers. Institutional variables were associated with the prevalence of malnutrition diagnosis, which suggests that institutional culture influences malnutrition diagnosis. Quality improvement efforts aimed at improved structure and process appear to be needed to improve the identification of malnutrition.  相似文献   
6.
The lack of availability of novel antibiotic agents and the rise of resistance to existing therapies has led clinicians to utilise combination therapy to adequately treat bacterial infections. Here we examined how chelators may impact the in vitro activity of tigecycline (TIG) against Pseudomonas aeruginosa, Escherichia coli and Klebsiella pneumoniae. Minimum inhibitory concentrations (MICs) were determined by broth dilution with and without various combinations of chelators (EDTA and other tetracyclines) and metal ions (i.e. calcium, magnesium). Trimethoprim (TMP) was used as a non-chelating control. Addition of metal ions led to increases in MICs, whilst addition of EDTA led to decreases in MICs. The chelating effects of EDTA were reversed by addition of magnesium and most profoundly calcium. Similar effects of EDTA and calcium were observed for tetracycline (TET) and TMP. When other tetracyclines (TET, oxytetracycline (OXY) and chlortetracycline (CHL)) were used as chelators at concentrations below their MICs, TIG MICs decreased for P. aeruginosa but not for E. coli. Some decreases in TIG MICs were observed for K. pneumoniae when TET and CHL were added. A dose-dependent decrease in TIG MIC was observed for TET and was reversed by the addition of calcium. The presence of effects of EDTA and calcium on TMP MICs indicates that mechanisms outside of TIG chelation likely play a role in enhanced activity. Full characterisation of an unexpected interaction such as TIG–TET with different microorganisms could provide valuable insights into the underlying mechanisms and design of physiologically viable chelators as candidates for future combinations regimens.  相似文献   
7.
8.
9.
BackgroundThere is a lack of objective dynamic knee joint control measures that can be related to the status of the anterior cruciate ligament (ACL). The purpose of this study was to introduce two novel measures and apply a third to determine how dynamic knee joint control changes in relation to ACL status during dynamic movements.MethodsTwenty patients (13 male) were tested pre- (ACLd) and 10-months post- (ACLr) ACL reconstructive surgery and matched to an uninjured participant (CON). Kinetic and kinematic data were synchronously recorded with a force platform and motion capture system. Three objective control measures including dynamic angular stiffness, knee joint center excursion (KJCE), and knee joint center boundary (KJCB) were assessed for each participant when completing the side cut and hop tasks.ResultsDuring the side cut, stiffness was found to be significantly lower in ACLd (0.06 ± 0.01 Nm/kg/°) and ACLr (0.07 ± 0.02 Nm/kg/°) compared to CON (0.08 ± 0.02 Nm/kg/°), while there were no differences in stiffness during the hop. No significant differences were observed in the KJCE during the side cut, while KJCE was significantly greater (p = 0.006) during the hop in CON compared to the ACLd. There were no differences in KJCB.ConclusionsThese high-functioning ACL injured in both ACLd and ACLr phases, aside from reduced stiffness, were able to complete both tasks with similar dynamic control as the CON. Although improvements in self-perceived control between ACLd and ACLr have been observed, this lack of improvement in objective control demonstrates a gap between a patient's self-efficacy and the level of control.  相似文献   
10.

Purpose

Potential roles of inherited and environmental risk factors in pathogenesis of Langerhans cell histiocytosis (LCH), a myeloid neoplastic disorder, are undefined. We therefore evaluated the role of parental and perinatal factors on the risk of this childhood cancer.

Methods

Information on LCH cases (n = 162) for the period 1995–2011 was obtained from the Texas Cancer Registry. Birth certificate controls were frequency-matched on year of birth at a ratio of 10:1 for the same period. Variables evaluated included parental age, race/ethnicity, size for gestational age, and birth order. Logistic regression was used to generate an adjusted odds ratio (aOR) and 95% confidence interval (CI) testing the association between each factor and LCH.

Results

Few perinatal or parental factors were associated with LCH risk, with the exception of race/ethnicity. Mothers of Hispanic ethnicity were more likely to have children who developed LCH compared to non-Hispanic whites (aOR: 1.51; 95% CI: 1.02–2.25). This risk increased when both parents were Hispanic (aOR: 1.80; 95% CI: 1.13–2.87). Non-Hispanic black mothers were suggested as less likely to give birth to offspring who developed LCH compared to non-Hispanic whites (aOR: 0.50; 95% CI: 0.24–1.02).

Conclusions

LCH is characterized by somatic mutations in MAPK pathway genes in myeloid precursors. Increased risk for LCH in children of Hispanic parents suggests potential impact of inherited factors on LCH pathogenesis.  相似文献   
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