Conventional measurement of mucosal turnover is based on labeling cellular DNA with [3H]thymidine, but because of the risk of genetic damage, this technique is not suitable for studies in normal human subjects. Consequently, we have measured mucosal protein turnover by a primed/continuous intravenous infusion of tracer quantities of [114C]leucine and measured its incorporation into mucosal protein at 4 hr in nine healthy adult volunteers. Mucosal samples were obtained by standard endoscopic techniques from the distal duodenum and gastric antrum. In addition, duodenal villous height and width were measured by microscopic micrometric techniques in order to calculate villous growth rate. Results demonstrated a mucosal protein turnover of 57±5%/day in gastric antrum and 39±2%/day in duodenum, suggesting a mucosal replacement rate of 1.8 and 2.6 days, respectively. Average duodenal villous height was 433±77 m, suggesting a villous growth rate of approximately 160 m/day. As our mucosal protein turnover rates are similar to epithelial turnover rates measured by cellular labeling techniques, our results support the intestinal proliferon theory that suggests all mucosal elements follow similar turnover characteristics. In conclusion, the technique should provide a practical alternative method of studying the effect of disease upon mucosal regeneration and repair. 相似文献
Background: this study was designed to characterize some of the biochemical and molecular genetic changes during reversion
of human fat cells. Methods: mature adipocytes were isolated from greater omental fat tissue of eight lean and 14 massively
obese persons by established methodology. Results: at day 7 of adherence to Leighton tubes, there was appreciable depletion
of triacylglycerol, as well as assumption of an elongated contour. Relatedly, there was an increase in the expression of β-actin
mRNA and a significant decrease in the specific activity of cytosolic glycerophosphate dehydrogenase. The decrement in the
specific activity of glycerophosphate dehydrogenase, after 7 days in culture, was significant at p < 0.001. Basic fibroblast growth factor at 10 ngml-1 accelerated significantly (p < 0.03) the decrease in the specific activity of glycerophosphate dehydrogenase in adipose cells from lean subjects. In contrast,
basic fibroblast growth factor had no significant influence on cells from massively obese persons. Conclusion: such resistance
may contribute to the intractability of massive obesity. 相似文献
Background: Vitamin B12 deficiency after gastric surgery for obesity is due to a failure of separation of vitamin B12 from protein foodstuffs and to a failure of absorption of crystalline vitamin B12 in the presence of intrinsic factor. The purpose of this study was to determine which of four oral doses of crystalline vitamin
B12 was most effective in treating vitamin B12 deficiency in 102 patients. Methods and Results: At time of entry into the study, the patients had a serum vitamin B12 < 100 pmol L −1, were 29.9 ± 21.7 months post-op, were 37 ± 8 years old and had a body mass index of 30 ± 6 kg m−2. Eight (8%) had had a vertical banded gastroplasty and 94 (92%) a gastric bypass. For the first 3 months all patients received
350 μg per day of crystalline vitamin B12 and all increased their serum vitamin B12 levels to over 100 pmol L−1. The patients were then assigned to receive for a further 3 month period one of four oral doses of crystalline vitamin B12-100 μg, 250 μg, 350 μg and 600 μg. Serum vitamin B12 levels were greater than 150 pmol L−1 after 6 months in 83.3% of patients who received 100 μg; 92.3% of patients who received 250 μg; 94.7% after 350 μg and 95.2%
after 600 μg (p%0.525). Conclusion: At least 350 μg per day is the appropriate oral dose of crystalline vitamin B12 after gastric surgery for obesity to correct low serum vitamin B12 levels in 95% of patients. 相似文献
Inositol is a simple polyol precursor in a second messenger system important in brain myo-insitol, the natural isomer, which
has been found to be therapeutically effective in depression, panic disorder, and obsessive-compulsive disorder in double-blind
controlled trials. Recently, epiinositol, an unnatural stereoisomer of myo-inositol, was found to have effects similar to
those of myo-inositol to reverse lithium-pilocarpine seizures. We measured the behavior of rats in an elevated plus maze model
of anxiety after chronic treatment of 11 daily intraperitoneal injections of epi-inositol, myo-inositol, or control solution.
Epi-inositol reduced anxiety levels of rats compared with controls, and its effect was stronger than that of myoinositol.
Lithium has been hypothesized to alleviate mania by reducing brain inositol levels. Inositol in brain derives from the second
messenger cycle, from new synthesis, or from diet via transport across the blood brain barrier. Because the first two are
inhibited by lithium, we propose that an inositol-free diet will augment lithium action in mania by enhancing restriction
of inositol. 相似文献
In vitro investigations into adipose cell dynamics have revealed intrinsic characteristics of massively obese individuals' cells that
could contribute to a relatively intractable expanded fat mass. Morbidly corpulent peoples' preadipocytes replicate to a greater
degree than those from lean individuals. Coupled with exaggerated differentiation this enhanced growth would result in a greater
number of fat cells which would increase adipose tissue mass. The relative resistance to de-differentiation that adipocytes
from the massively obese demonstrate would contribute to stability of an increased number of adipocytes further exacerbating
the problem. The increased message of an energy sensing protein, the obese gene product, suggests that the morbidly obese are insensitive to its action. Together these attributes provide a strong
argument for a significant genetic role in the pathogenesis of obesity. 相似文献
Objectives. Mexican Americans (MAs), compared to white non‐Hispanics (WNHs), have higher rates of biliary disease, noninsulin dependent diabetes, and endstage renal disease but lower rates of lung cancer, hip fractures, and mortality from coronary heart disease. Relatively little research has been done to identify other ethnic differences in disease incidence. We used surgical procedure rates to confirm known ethnic differences and to explore our clinical suspicion that MAs have higher rates of appendectomy than WNHs.
Methods. We used a registry of surgical procedures at two teaching hospitals in South Texas to calculate proportional operation ratios (PORs) for MAs versus WNHs. These two hospitals are the primary source of acute hospital care for the indigent in the area. The POR is arithmetically identical to proportional incidence and mortality ratios.
Results. MAs underwent appendectomy proportionally more often than WNHs at both hospitals (POR = 1.41 and 1.75, p < 0.0001). Other significant PORs were consistent with known ethnic disease differences in biliary tract operations, vascular access for chronic hemodialysis, lung cancer, and coronary artery bypass.
Conclusions. These findings support the hypothesis that MAs may undergo appendectomy more often than WNHs and so may be at higher risk of appendicitis. 相似文献
To determine whether "folk myths" regarding the relationships of penile size to body height and foot size have any basis in fact, 63 normally virilized men were studied. Height and stretched penile length were measured; shoe size was recorded and converted to foot length. Penile length was found to be statistically related to both body height and foot length, but with weak correlation coefficients. Height and foot size would not serve as practical estimators of penis length. 相似文献
BACKGROUND AND AIMS: The aim of this retrospective study was to compare the relative costs of treating simple and spiral wedge (requiring closed reduction under anaesthesia) tibial shaft fractures in a plaster cast or with intramedullary locking nail. MATERIAL AND METHODS: The material consisted of 26 fractures treated in a plaster cast and 51 fractures treated with an intramedullary locking nail. The costs caused by the direct costs (treatment, hospitalisation, and outpatient appointments) as well as indirect costs (lost productivity) were taken into account. Costs caused by complications were also included in the analysis. RESULTS: Mean direct costs per patient were FIM 22920 and FIM 26952 and mean overall costs per patient were FIM 120486 and FIM 82224 in plaster cast and intramedullary locking nailing groups, respectively (FIM 1 = USD 0.19). The higher mean overall costs of the plaster cast group were attributable to the longer sick leave periods in this group (218 days in plaster cast group and 124 in intramedullary nailing group). CONCLUSION: Plaster cast treatment of simple and spiral wedge tibial shaft fractures requiring closed reduction under anaesthesia is more expensive to society than operative treatment with intramedullary locking nail. 相似文献
CONTEXT: Despite advances in early detection and prevention of cervical cancer, women living in rural areas, and particularly in Appalachia, the rural South, the Texas/Mexico border, and the central valley of California, have had consistently higher rates of cervical cancer mortality than their counterparts in other areas during the past several decades. METHODS: This paper reviews the published literature from 1966 to July 2002 to assess three potential pathways underlying this excess mortality--high human papilloma virus (HPV) prevalence, lack of or infrequent screening and advanced disease at diagnosis, and under-use of recommended treatment and shorter survival. FINDINGS: Living in rural areas may impose barriers to cervical cancer control, including lack of transportation and medical care infrastructures. Population characteristics that place women at greater risk for developing and dying from cervical cancer, such as low income, lack of health insurance, and physician availability, are concentrated in rural areas. Published data, however, are insufficient to identify the key reasons for the observed mortality patterns. CONCLUSIONS: At this time, given the lack of definitive evidence in the published literature, decisions about priorities in areas with high rates of cervical cancer mortality will depend on knowledge of current levels of screening, incidence, and stage distribution; and service delivery infrastructures, resources, and acceptability of interventions to the target population. 相似文献