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11.
BACKGROUND: Flexion distraction has gained increased credibility as a therapeutic modality for treatment of low back pain. Although important work in the area has elucidated the intradiskal pressure profiles during flexion distraction, the accompanying neural responses have yet to be described. OBJECTIVE: The purpose of this pilot study was to assess neural reflex responses to motion with 3 degrees of freedom applied to the lumbar spine and to evaluate H-reflex responses of the soleus. METHODS: Subjects (n = 12) were measured for H-maximum reflexes determined from stimulus response recruitment curves measured in neutral prone position. The mean of 10 evoked H-waves (at H-maximum stimulus intensity) were measured in neutral position, flexion, left and right lateral flexion, and axial rotation of the trunk on an adjusting table. H-reflexes were expressed as a percentage of maximal M-wave for the criterion measure. Spinal range of motion was quantified by digitization. RESULTS: The data showed variation in some movement ranges, notwithstanding identical table positioning for all subjects. Mean H-reflex amplitude was decreased (15.2 +/- 5.8 mV to 13.8 +/- 5.8 mV), and the H/M ratio was also decreased in flexion compared with neutral (55.0% +/- 19.1% to 50.3% +/- 19.4%; P <.05). CONCLUSIONS: Trunk flexion is accompanied by inhibition of the motor neuron pool. Slight perturbations in numerous afferent receptors are known to significantly alter the H-reflex. The absence of measurable changes in lateral flexion and trunk rotation may indicate that both slow- and fast-adapting receptors could be involved in lumbar motion. These preliminary findings suggest the need for further dynamic motion studies of the flexion distraction neurophysiologic condition.  相似文献   
12.
Carcinogenesis of Helicobacter pylori   总被引:9,自引:0,他引:9  
Helicobacter infection is the leading cause of gastric cancer worldwide. Infection with this ubiquitous bacterium incites a chronic active immune response that persists for the life of the host, in the absence of antibiotic-induced eradication. It is the combination of bacterial factors, environmental insults, and the host immune response that drives the initiation and progression of mucosal atrophy, metaplasia, and dysplasia toward gastric cancer. Although it may seem intuitively obvious that removing the offending organism would negate the cancer risk, this approach is neither feasible (half of the world harbors this infection) nor is it straightforward. Most patients are infected in childhood, and present with various degrees of mucosal damage before any therapy. This review outlines the histologic progression of human Helicobacter infection from the early stages of inflammation through the development of metaplasia, dysplasia, and, finally, cancer. The effects of dietary and bacterial eradication therapy on disease progression and lesion reversibility are reviewed within the context of population studies and compared between study designs and populations tested. Eradication studies in the mouse model of infection prevents the formation of gastric cancer, and allows regression of established lesions, providing a useful model to study interaction between bacterium, environment, and host, without the difficulties inherent in human population studies. Recent advances in identifying the bone marrow-derived stem cell as the cell of origin of Helicobacter-induced gastric cancer in the murine model are discussed and interpreted in the context of human disease, and implications for future treatment are discussed.  相似文献   
13.
OBJECTIVE: The purpose of this study was to report preliminary data on the effects of tea and high-protein meal replacement shakes on weight loss, waist-to-hip ratios, and lipid profiles in healthy subjects. Secondary analyses of urine samples assessed pre-post changes in cellular biochemistry, neurochemistry, and microbial metabolism. METHODS: This study used a pre-post intervention design without a control group. Thirty healthy subjects (20-60 years of age; 23 women and 7 men) participated in a 28-day diet intervention program consisting of a cleansing day and 6 restricted diet days per week. On cleansing days, the subjects drank 4 oz of tea 4 times per day with a recommendation to drink at least 64 oz of filtered water. On the restricted diet days, the subjects drank 2 high-protein meal replacement shakes, consumed one 400- to 600-cal (1674.3-2511.5 joules) meal consisting of low-glycemic index foods, and drank at least 64 oz of filtered water. RESULTS: Multiple paired t tests detected reductions in weight (6.4 lb), waist (1.9 in), and hip (1.1 in) measurements and in total cholesterol (13.3 mg/dL) and low-density lipoprotein cholesterol (11.4 mg/dL) (P < .05). Multiple paired t tests detected significant increases in energy metabolism from carbohydrates and amino acids and concomitant increases in oxidative stress (P < .05). CONCLUSION: The data support the concept that a low-glycemic load diet intervention incorporating tea and high-protein meal replacement shakes may cause weight loss and improve lipid profiles. The significant physiologic changes from the urine samples did not reflect meaningful metabolic effects.  相似文献   
14.

Objective

Although not recommended as first line therapy by consensus guidelines, opioid analgesics are commonly used to treat headaches. This study evaluates trends in opioid use for headaches in US emergency departments (EDs).

Methods

We performed a retrospective review of the National Hospital Ambulatory Medical Care Survey, 2001 through 2010. Adult headache-related visits were identified. Medications (opioid and nonopioid) used for the treatment of headache were categorized based on medication class. Trends in ED use of the most common opioids (codeine, hydrocodone, hydromorphone, morphine, and oxycodone) were explored. The proportion of visits for which each medication was used was tabulated, and trends were analyzed using survey-weighted logistic regression.

Results

Headache visits during which any opioid was used increased between 2001 (20.6%; 95% confidence interval [CI], 18.1-23.4) and 2010 (35.0%; 95% CI, 31.8-38.4; P < .001). Prescribing of hydromorphone, morphine, and oxycodone increased, with the largest relative increase (461.1%) in hydromorphone (2001, 1.8% [95% CI, 1.2-2.6]; 2010, 10.1% [95% CI, 8.2-12.4]). Codeine use declined, and hydrocodone use remained stable. Use of opioid alternatives, including acetaminophen, butalbital, and triptans did not change over the study period, whereas use of nonsteroidal anti-inflammatory drugs increased from 26.2% (95% CI, 23.0-29.7) to 31.4% (95% CI, 28.6-34.3). Prescribing of antiemetic agents decreased from 24.1% (95% CI, 19.6-29.2) to 23.5% (95% CI, 21.1-26.0). Intravenous fluid use increased from 20.0% (95% CI, 17.0-23.4) to 34.5% (95% CI, 31.0-38.2) of visits.

Conclusions

Despite limited endorsement by consensus guidelines, there was increased use of opioid analgesics to treat headaches in US EDs over the past decade.  相似文献   
15.
An increasing percentage of US cocaine has been adulterated with levamisole, an immunomodulator associated with agranulocytosis. We describe 3 emergency department patients with hyponatremia and cocaine use. Despite extensive evaluation, the cause of the hyponatremia was not elucidated but resolved during hospitalization. Because hyponatremia has not previously been associated with cocaine, we sought to uncover a plausible explanation that might be contributing to this new finding. Levamisole was detected in all 3 patients. Although we are unable to confirm causality, we propose that levamisole-adulterated cocaine may have contributed to the hyponatremia described in these patients.  相似文献   
16.
17.
Escape from normal apoptotic controls is thought to be essential for the development of cancer. During Helicobacter pylori infection, the leading cause of gastric cancer, activation of the Fas antigen (Fas Ag) apoptotic pathway is responsible for early atrophy and tissue loss. As disease progresses, metaplastic and dysplastic glands arise which express Fas Ag but are resistant to apoptosis and are believed to be the precursor cells for adenocarcinoma. In this report, we show that one mechanism of acquired Fas resistance is inhibition of receptor aggregation via a major histocompatibility complex class II (MHCII)-mediated, actin-dependent mechanism. For these studies we used the well-described C57BL/6 mouse model of Helicobacter pylori and Helicobacter felis infection. Under normal conditions, Fas Ag is expressed at low levels, and MHCII expression on gastric mucosal cells is negligible. With infection and inflammation, both receptors are upregulated, and 6.1% of gastric mucosal cells express MHCII in combination with Fas Ag. Using the rat gastric mucosal cell line RGM-1 transfected with murine Fas Ag and MHCIIalphabeta chains, we demonstrate that MHCII prevents Fas receptor aggregation and inhibits Fas-mediated signaling through its effects on the actin cytoskeleton. Depolymerization of actin with cytochalasin D allows receptors to aggregate and restores Fas sensitivity. These findings offer one mechanism by which gastric mucosal cells acquire Fas resistance.  相似文献   
18.
This report describes the development and pre-clinical testing of a new, random-access RNA sample preparation system (TruTip) for nasopharyngeal samples. The system is based on a monolithic, porous nucleic acid binding matrix embedded within an aerosol-resistant pipette tip and can be operated with single or multi-channel pipettors. Equivalent extraction efficiencies were obtained between automated QIAcube and manual TruTip methods at 10(6) gene copies influenza A per mL nasopharyngeal aspirate. Influenza A and B amended into nasopharyngeal swabs (in viral transport medium) were detected by real-time RT-PCR at approximately 745 and 370 gene copies per extraction, respectively. RNA extraction efficiency in nasopharyngeal swabs was also comparable to that obtained on an automated QIAcube instrument over a range of input concentrations; the correlation between threshold cycles (or nucleic acid recovery) for TruTip and QIAcube-purified RNA was R(2)>0.99. Preclinical testing of TruTip on blinded nasopharyngeal swab samples resulted in 98% detection accuracy relative to a clinically validated easyMAG extraction method. The physical properties of the TruTip binding matrix and ability to customize its shape and dimensions likewise make it amenable to automation and/or fluidic integration.  相似文献   
19.

Objective

An ink pad and paper, pressure-sensitive platforms, and photography have previously been used to collect footprint data used in clinical assessment. Digital scanners have been widely used more recently to collect such data. The purpose of this study was to evaluate the intra- and interrater reliability of a flatbed digital image scanning technology to capture footprint data.

Methods

This study used a repeated-measures design on 32 (16 male 16 female) healthy subjects. The following measured indices of footprint were recorded from 2-dimensional images of the plantar surface of the foot recorded with an Associate Platinum (Foot Levelers Inc, Roanoke, VA) digital foot scanner: Staheli index, Chippaux-Smirak index, arch angle, and arch index. Intraclass correlation coefficient (ICC) values were calculated to evaluate intrarater, interday, and interclinician reliability.

Results

The ICC values for intrarater reliability were greater than or equal to .817, indicating an excellent level of reproducibility in assessing the collected images. Analyses of variance revealed that there were no significant differences between raters for each index (P > .05). The ICC values also indicated excellent reliability (.881-.971) between days and clinicians in all but one of the indices of footprint, arch angle (.689), with good reliability between clinicians. The full-factorial analysis of variance model did not reveal any interaction effects (P > .05), which indicated that indices of footprint were not changing across days and clinicians.

Conclusions

Scanning technology used in this study demonstrated good intra- and interrater reliability measurements of footprint indices, as demonstrated by high ICC values.  相似文献   
20.
The Office of the U.S. Surgeon General has described osteoporosis as a major public health concern that is both underdiagnosed and undertreated. Educating women about modifiable risk factors and encouraging them to alter and maintain lifestyle choices that improve bone density is essential for their bone health. Evaluating those at risk using laboratory measures and dual X‐ray absorptiometry (DXA), and appropriate therapeutic intervention followed by monitoring for compliance and treatment effectiveness should result in risk reduction and improved bone health.  相似文献   
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