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1.

Background and aims

It is not known whether non alcoholic fatty liver disease (NAFLD) is a risk factor for diabetes in non obese, non centrally-obese subjects. Our aim was to investigate relationships between fatty liver, insulin resistance and a biomarker score for liver fibrosis with incident diabetes at follow up, in subjects who were neither obese nor centrally-obese.

Methods and results

As many as 70,303 subjects with a body mass index (BMI) < 25 kg/m2 and without diabetes were followed up for a maximum of 7.9 years. At baseline, fatty liver was identified by liver ultrasound, insulin resistance (IR) by homeostatic model assessment of insulin resistance (HOMA-IR) ≥2.0, and central obesity by waist circumference (waist circumference ≥90 cm (men) and ≥85 cm (women). The Fibrosis-4 (FIB-4 score) was used to estimate extent of liver fibrosis. Cox proportional hazards models adjusted for confounders were used to estimate hazard ratios (aHRs) for incident diabetes. As many as 852 incident cases of diabetes occurred during follow up (median [IQR] 3.71 [2.03] years). Mean ± SD BMI was 22.8 ± 1.8 and 21.7 ± 2.0 kg/m2 in subjects with and without diabetes at follow up. In subjects without central obesity and with fatty liver, aHRs (95% CI) for incident diabetes at follow up were 2.17 (1.56, 3.03) for men, and 2.86 (1.50,5.46) for women. Similar aHRs for incident diabetes occurred with fatty liver, IR and the highest quartile of FIB-4 combined, in men; and there was a non significant trend toward increased risk in women.

Conclusions

In normal weight, non-centrally obese subjects NAFLD is an independent risk factor for incident diabetes.  相似文献   
2.
Although surgical lung resection could improve prognosis in some patients with multidrug-resistant tuberculosis (MDR-TB), there are no reports on the optimal candidates for this surgery. The aim of the present study was to elucidate the prognostic factors for surgery in patients with MDR-TB. Patients who underwent lung resection for the treatment of MDR-TB between March 1993 and December 2004 were included in the present study. Treatment failure was defined as greater than or equal to two of the five cultures recorded in the final 12 months of treatment being positive, any one of the final three cultures being positive, or the patient having died during treatment. The variables that affected treatment outcomes were identified through univariate and multivariate logistic regression analysis. In total, 79 patients with MDR-TB were included in the present study. The treatment outcomes of 22 (27.8%) patients were classified as failure. A body mass index <18.5 kg x m(-2), primary resistance, resistance to ofloxacin and the presence of a cavitary lesion beyond the range of the surgical resection were associated with treatment failure. Low body mass index, primary resistance, resistance to ofloxacin and cavitary lesions beyond the range of resection are possible poor prognostic factors for surgical lung resection in multidrug-resistant tuberculosis patients.  相似文献   
3.
Generally, a computed tomography scan is conducted for the diagnosis of stroke in the emergency department, because these scans are easier and faster in the detection of stroke. If there are no signs of hemorrhage on computed tomography scan, an ischemic stroke is diagnosed and treated accordingly. A magnetic resonance imaging scan may be taken in order to verify ischemic stroke. This process may lead to improper treatment and is time consuming. To address this situation, case studies are presented in which magnetic resonance imaging diffusion-weighted imaging and gradient recalled echo were performed to detect hemorrhagic and ischemic stroke and particularly, subarachnoid hemorrhage, which is undetectable with a computed tomography scan.  相似文献   
4.
Pituitary abscess is a rare and potentially lethal condition. Pituitary abscess in a pregnant woman has not been previously described. A 38-year-old pregnant woman (34 weeks gestation) with a pituitary mass complained of a progressive headache and sudden visual impairment. She was afebrile and had no inflammatory symptoms on admission. On MRI, the preoperative diagnosis was pituitary adenoma with sphenoid sinusitis. She underwent an uncomplicated transsphenoidal procedure for removal of the pituitary mass. The next day, labor commenced and a healthy preterm baby was delivered. Pathologic examination of the intrasellar mass showed polymorphonuclear cells, debris and no tumor cells. The sellar contents were cultured and Streptococcus viridans was grown. To our knowledge this is the first case of pituitary abscess reported during pregnancy. Although the patient was pregnant, the transsphenoidal approach was safe for the mother and the fetus. Surgical drainage and antibiotic therapy are required for the definitive treatment of this condition.  相似文献   
5.
The development and testing of candidate vaccines for trachoma are constrained because only humans and nonhuman primates are susceptible to conjunctival infection with Chlamydia trachomatis. Guinea pig inclusion conjunctivitis (GPIC), an analogous disease of guinea pigs, provides a useful, less expensive model to study ocular chlamydial infections. GPIC is caused by a Chlamydia psittaci strain whose external constituents are very similar to those of C. trachomatis. To develop a better model for studying GPIC immunity, conjunctival pockets were established under the abdominal skin of guinea pigs by subcutaneous implantation. Up to six implants could be produced in each animal. The success rate of implantation was 79.0% (n = 148). These pockets were then infected with GPIC. The organism was recovered from the autografts indicating local replication, and tests for serum antibody by microimmunofluorescence showed production of GPIC-specific antibody of IgG and IgM classes after infection. There was minimal antibody response after moderate inoculating doses to the implants, and the titers increased more slowly than after eye infection with GPIC; with higher concentration of the inoculum, however, the antibody response increased to the same levels as with the ocular challenge but more slowly. Inoculation of pockets with GPIC also produced acute inflammatory changes in infected autografts (n = 101). Histologic examination of infected grafts showed chlamydial inclusions in epithelial cells and significant infiltration with lymphocytes and polymorphonuclear cells. Subcutaneous autografts may provide a useful model for chronologic studies of chlamydial infection. The delayed immunologic response, however, suggests that these pockets of implanted epithelium do not have full access to the immune system.  相似文献   
6.
Transforming growth factor-β1 (TGF-β1) is known to be a potent growth inhibitor for many cell types, including most epithelial cells. In skin keratinocytes, TGF-β1 has been shown to inhibit growth and to rapidly reduce c-mycexpression. However, the molecular mechanism of TGF-β1 action on cell growth of cervical carcinoma has not yet been elucidated. We thus assessed the effect of TGF-β1 on the growth of cervical carcinoma cell lines. Two cervical squamous carcinoma cell lines, CUMC-3 and CUMC-6, were incubated with varying concentrations of TGF-β1, and growth inhibition was evaluated with tetrazolium-based colorimetric assay. After culture in TGF-β1 for 24 h, inhibition of growth was detected in a dose-dependent manner at concentrations of 0.1–10 ng/ml in both cell lines. This effect of TGF-β1 on cultured carcinoma cells was associated with apoptotic process including oligonucleosomal ladder DNA and apoptotic body formations. Northern blot analysis revealed c-mycmRNA expression was suppressed by 10 ng/ml of TGF-β1 following 3 h of treatment in both cell lines. Western blot analysis showed that the level of p27Kip1protein was increased after TGF-β1 treatment in both cell lines. These results suggest that the mechanisms by which TGF-β1 inhibits the growth of cervical carcinoma are complex and may include effects on down-regulation of c-mycgene, and overexpression of p27Kip1protein.  相似文献   
7.
8.
Effects of sodium salts of various monovalent inorganic anions on transdermal permeation of salicylic acid were investigated. In in-vitro experiment using a Franz-type diffusion cell and excised mouse skin, the permeation-enhancing activities of the sodium salts of inorganic anions were roughly proportional to lyotropic Hofmeister swelling abilities of the anions; F?<SO4 2?<Cl? <ClO4 ?<NO3 <SCN? <Br <I?, i.e. l, Br and SCN increased the flux of drugs through the mouse skin, while F?, SO4 2?, Cl?, ClO4 ? and NO3 ? decreased or did not affect the flux. In invivo experiment using the rabbit as the test animal, the plasma concentration of salicylic acid of the rabbit to which 10%-salicylic acid ointment containing 5%-Nal or NaBr was applied was significantly higher than that of the rabbit to which the ointment without the electrolytes was applied. The amounts of sterol leached out of stratum corneum sheet when the sheet was immersed in aqueous solutions of Nal, NaBr, or NaSCN were much more than that of stratum corneum immersed in aqueous solutions of the other inorganic anions. The FTIR/ATR spectroscopy showed that the peaks at 2853 cm?1 and 2924 cm?1 in the IR absorption spectrum of the stratum corneum sheet of the mouse were shifted to higher frequencies by the anions which enhanced the transdermal drug permeation, while not shifted by the anions which did not have any permeation-enhancing activities or have permeation-reducing activities. These results suggest that sodium salts of some anions such as iodide, bromide and thiocyanate enhance transdermal permeation of salicylic acid through swelling and perturbation of the skin structure by these anions.  相似文献   
9.
10.
Performance measurement of the microPET focus 120 scanner.   总被引:6,自引:0,他引:6  
The microPET Focus 120 scanner is a third-generation animal PET scanner dedicated to rodent imaging. Here, we report the results of scanner performance testing. METHODS: A (68)Ge point source was used to measure energy resolution, which was determined for each crystal and averaged. Spatial resolution was measured using a (22)Na point source with a nominal size of 0.25 mm at the system center and various off-center positions. Absolute sensitivity without attenuation was determined by extrapolating the data measured using an (18)F line source and multiple layers of absorbers. Scatter fraction and counting rate performance were measured using 2 different cylindric phantoms simulating rat and mouse bodies. Sensitivity, scatter fraction, and noise equivalent counting rate (NECR) experiments were repeated under 4 different conditions (energy window, 250 approximately 750 keV or 350 approximately 650 keV; coincidence window, 6 or 10 ns). A performance phantom with hot-rod inserts of various sizes was scanned, and several animal studies were also performed. RESULTS: Energy resolution at a 511-keV photopeak was 18.3% on average. Radial, tangential, and axial resolution of images reconstructed with the Fourier rebinning (FORE) and filtered backprojection (FBP) algorithms were 1.18 (radial), 1.13 (tangential), and 1.45 mm full width at half maximum (FWHM) (axial) at center and 2.35 (radial), 1.66 (tangential), and 2.00 mm FWHM (axial) at a radial offset of 2 cm. Absolute sensitivities at transaxial and axial centers were 7.0% (250 approximately 750 keV, 10 ns), 6.7% (250 approximately 750 keV, 6 ns), 4.0% (350 approximately 650 keV, 10 ns), and 3.8% (350 approximately 650 keV, 6 ns). Scatter fractions were 15.9% (mouse phantom) and 35.0% (rat phantom) for 250 approximately 750 keV and 6 ns. Peak NECR was 869 kcps at 3,242 kBq/mL (mouse phantom) and 228 kcps at 290 kBq/mL (rat phantom) at 250 approximately 750 keV and 6 ns. Hot-rod inserts of 1.6-mm diameter were clearly identified, and animal studies illustrated the feasibility of this system for studies of whole rodents and mid-sized animal brains. CONCLUSION: The results of this independent field test showed the improved physical characteristics of the F120 scanner over the previous microPET series systems. This system will be useful for imaging studies on small rodents and brains of larger animals.  相似文献   
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