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21.

Introduction

Intraocular hemorrhage in patients suffering from aneurysmal subarachnoid hemorrhage is known as Terson''s syndrome and is an underestimated but common pathology. We therefore designed a prospective single-blinded study to evaluate the validity of ocular ultrasound compared to the gold standard indirect funduscopy in the diagnosis of Terson''s syndrome.

Material and Methods

Fifty-two patients (104 eyes in total) suffering from aneurysmal subarachnoid hemorrhage were enrolled in this study. Two investigators independently performed a single-blinded ocular ultrasound using a standard intensive care ultrasound system to detect an intraocular hemorrhage. Indirect funduscopy following iatrogenic mydriasis served as the gold standard for confirmation or exclusion of an intraocular hemorrhage. Statistical analyses were performed to evaluate the sensitivity and specificity, positive and negative predictive values of the method as well as the learning curve of ocular ultrasound.

Results

Indirect funduscopy detected Terson''s syndrome in 11 of 52 (21.2%) respectively in 21 of 104 (20.2%) eyes in patients suffering from subarachnoid hemorrhage. Sensitivity and specificity increased with the number of ocular ultrasound examinations for both investigators, reaching 81.8% and 100% respectively. Positive and negative predictive values were different for both investigators (63.6% vs. 100% positive and 100% vs. 95.7% negative) but were both correlated to the amount of intraocular hemorrhage. A low Glasgow Coma scale (p = 0.015) and high Hunt & Hess grade (p = 0.003) was associated with a higher rate of Terson''s syndrome.

Conclusions

Ocular ultrasound using standard ultrasound equipment has been confirmed as a reliable, easy-to-handle bedside screening tool for detecting Terson''s syndrome. Nevertheless funduscopy remains the gold standard to detect Terson''s syndrome.  相似文献   
22.

Background

The gene encoding a thermostable cellulase of family 12 was previously isolated from a Rhodothermus marinus through functional screening. CelA is a protein of 260 aminoacyl residues with a 28-residue amino-terminal signal peptide. Mature CelA was poorly synthesized in some Escherichia coli strains and not at all in others. Here we present an alternative approach for its heterologous production as a secreted polypeptide in Streptomyces.

Results

CelA was successfully over-expressed as a secreted polypeptide in Streptomyces lividans TK24. To this end, CelA was fused C-terminally to the secretory signal peptide of the subtilisin inhibitor protein (Sianidis et al. in J Biotechnol. 121: 498–507, 2006) from Streptomyces venezuelae and a new cloning strategy developed. Optimal growth media and conditions that stall biomass production promote excessive CelA secretion. Under optimal growth conditions in nutrient broth medium, significant amounts of mature CelA (50–90 mg/L or 100–120 mg/g of dry cell weight) are secreted in the spent growth media after 7 days. A protocol to rapidly purify CelA to homogeneity from culture supernatants was developed and specific anti-sera raised against it. Biophysical, biochemical and immmuno-detection analyses indicate that the enzyme is intact, stable and fully functional. CelA is the most thermostable heterologous polypeptide shown to be secreted from S. lividans.

Conclusion

This study further validates and extends the use of the S. lividans platform for production of heterologous enzymes of industrial importance and extends it to active thermostable enzymes. This study contributes to developing a platform for poly-omics analysis of protein secretion in S. lividans.
  相似文献   
23.
Seasonal variations in the volume of milk in Norwegian goat dairy farming complicate the production of brand goat cheeses. In the specialised goat dairy farming system most kids are culled shortly after birth without utilising the meat. In this paper the farm economics of an alternative system with altered period of kidding (currently from January to March) combined with the production of meat and cashmere fibre, is examined. May kidding combined with raising the kids for 8 or 20 months yielded the most promising economical return. Raising the kids for 1 year is also profitable when kidding takes place in February while December kidding seems to perform best with the present system of culling the kids right after birth. Cashmere fibre production seems to be profitable on Norwegian dairy goat farms and fibre and meat could become an option in countries seeking to improve incomes on dairy goat farms. Compared to the present system the changes would also be favourable from an animal welfare point of view.  相似文献   
24.
Brucellosis is one of the most widespread bacterial zoonoses worldwide. Here, our aim was to identify the effector mechanisms controlling the early stages of intranasal infection with Brucella in C57BL/6 mice. During the first 48 hours of infection, alveolar macrophages (AMs) are the main cells infected in the lungs. Using RNA sequencing, we identified the aconitate decarboxylase 1 gene (Acod1; also known as Immune responsive gene 1), as one of the genes most upregulated in murine AMs in response to B. melitensis infection at 24 hours post-infection. Upregulation of Acod1 was confirmed by RT-qPCR in lungs infected with B. melitensis and B. abortus. We observed that Acod1-/- C57BL/6 mice display a higher bacterial load in their lungs than wild-type (wt) mice following B. melitensis or B. abortus infection, demonstrating that Acod1 participates in the control of pulmonary Brucella infection. The ACOD1 enzyme is mostly produced in mitochondria of macrophages, and converts cis-aconitate, a metabolite in the Krebs cycle, into itaconate. Dimethyl itaconate (DMI), a chemically-modified membrane permeable form of itaconate, has a dose-dependent inhibitory effect on Brucella growth in vitro. Interestingly, structural analysis suggests the binding of itaconate into the binding site of B. abortus isocitrate lyase. DMI does not inhibit multiplication of the isocitrate lyase deletion mutant ΔaceA B. abortus in vitro. Finally, we observed that, unlike the wt strain, the ΔaceA B. abortus strain multiplies similarly in wt and Acod1-/- C57BL/6 mice. These data suggest that bacterial isocitrate lyase might be a target of itaconate in AMs.  相似文献   
25.
26.
Human life expectancy is increasing faster lately and, consequently, the number of patients with age-related diseases such as type 2 diabetes (T2D) is rising every year. Cases of hyperinsulinemia have been extensively reported in elderly subjects and this alteration in blood insulin concentration is postulated to be a cause of insulin resistance, which in some cases triggers T2D onset. Thus, it is important to know the underlying mechanisms of age-dependent hyperinsulinemia to find new strategies to prevent T2D in elderly subjects. Two processes control blood insulin concentration: Insulin secretion by the endocrine portion of the pancreas and insulin clearance, which occurs mainly in the liver by the action of the insulin-degrading enzyme (IDE). Here, we demonstrated that 10-month-old mice (old) display increased body and fat pad weight, compared with 3-month-old mice (control), and these alterations were accompanied by glucose and insulin intolerance. We also confirm hyperinsulinemia in the old mice, which was related to increased insulin secretion but not to reduced insulin clearance. Although no changes in insulin clearance were observed, IDE activity was lower in the liver of old compared with the control mice. However, this decreased IDE activity was compensated by increased expression of IDE protein in the liver, thus explaining the similar insulin clearance observed in both groups. In conclusion, at the beginning of aging, 10-month-old mice do not display any alterations in insulin clearance. Therefore, hyperinsulinemia is initiated primarily due to a higher insulin secretion in the age-related metabolic dysfunction in mice.  相似文献   
27.
The outbreak of Shiga toxin producing E.coli O104:H4 in northern Germany in 2011 was one of the largest worldwide and involved mainly adults. Post-diarrheal hemolytic uremic syndrome (HUS) occurred in 22% of STEC positive patients. This study’s aim was to assess risk factors for HUS in STEC-infected patients and to develop a score from routine hospital parameters to estimate patient risks for developing HUS. In a cohort analysis, adult patients with STEC infection were included in five participating hospitals in northern Germany between May and July 2011. Clinical data were obtained from questionnaires and medical records, laboratory data were extracted from hospitals’ electronic data systems. HUS was defined as thrombocytopenia, hemolytic anemia and acute renal dysfunction. Random forests and multivariate logistic regression were used to identify risk factors for HUS and develop a score using the estimated coefficients as weights. Among 259 adults with STEC infection, vomiting (OR 3.48,95%CI 1.88–6.53), visible blood in stools (OR 3.91,95%CI1.20–16.01), age above 75 years (OR 3.27, 95%CI 1.12–9.70) and elevated leukocyte counts (OR 1.20, 95%CI 1.10–1.31, per 1000 cells/mm3) were identified as independent risk factors for HUS. A score using these variables has an area under the ROC curve of 0.74 (95%CI 0.68–0.80). Vomiting, visible blood in stools, higher leukocyte counts, and higher age indicate increased risk for developing HUS. A score using these variables might help to identify high risk patients who potentially benefit from aggressive pre-emptive treatment to prevent or mitigate the devastating consequences of HUS.  相似文献   
28.
In unstationary swimming (changing velocity), some of the water around the swimmer is set in motion. This can be thought of as an added mass (Ma) of water. The purpose of this study was to find added mass on human swimmers and investigate the effect of shape and body size. Thirty subjects were connected to a 2.8 m long bar with handles, attached with springs (stiffness k=318 N/m) and a force cell. By oscillating this system vertically and registering the period of oscillations it was possible to find the added mass of the swimmer, given the known masses of the bar and swimmer. Relative added mass (Ma%) for boys, women and men were, respectively, 26.8±2.9%, 23.6±1.6% and 26.8±2.3% of the subjects total mass. This study reported significantly lower added mass (p<0.001) and relative added mass (p<0.002) for women compared to men, which indicate that the possible body shape differences between genders may be an important factor for determining added mass. Boys had significantly lower (p<0.001) added mass than men. When added mass was scaled for body size there were no significant differences (p=0.996) between boys and men, which indicated that body size is an important factor that influences added mass. The added mass in this study seems to be lower and within a smaller range than previously reported (Klauck, 1999, Eik et al., 2008). It is concluded that the added mass in human swimmers, in extended gliding position, is approximately 1/4 of the subjects’ body mass.  相似文献   
29.
Obesity predisposes to glucose intolerance and type 2 diabetes (T2D). This disease is often characterized by insulin resistance, changes in insulin clearance, and β-cell dysfunction. However, studies indicate that, for T2D development, disruptions in glucagon physiology also occur. Herein, we investigated the involvement of glucagon in impaired glycemia control in monosodium glutamate (MSG)-obese mice. Male Swiss mice were subcutaneously injected daily, during the first 5 days after birth, with MSG (4 mg/g body weight [BW]) or saline (1.25 mg/g BW). At 90 days of age, MSG-obese mice were hyperglycemic, hyperinsulinemic, and hyperglucagonemic and had lost the capacity to increase their insulin/glucagon ratio when transitioning from the fasting to fed state, exacerbating hepatic glucose output. Furthermore, hepatic protein expressions of phosphorylated (p)-protein kinase A (PKA) and cAMP response element-binding protein (pCREB), and of phosphoenolpyruvate carboxykinase (PEPCK) enzyme were higher in fed MSG, before and after glucagon stimulation. Increased pPKA and phosphorylated hormone-sensitive lipase content were also observed in white fat of MSG. MSG islets hypersecreted glucagon in response to 11.1 and 0.5 mmol/L glucose, a phenomenon that persisted in the presence of insulin. Additionally, MSG α cells were hypertrophic displaying increased α-cell mass and immunoreactivity to phosphorylated mammalian target of rapamycin (pmTOR) protein. Therefore, severe glucose intolerance in MSG-obese mice was associated with increased hepatic glucose output, in association with hyperglucagonemia, caused by the refractory actions of glucose and insulin in α cells and via an effect that may be due to enhanced mTOR activation.  相似文献   
30.
A rapid and simple method for the simultaneous quantification of AFB1 and OTA in rat plasma, liver and kidney by UHPLC-FLD has been successfully validated according to the following criteria: selectivity, stability, linearity, precision, accuracy, recovery, robustness and limits of quantification and detection. The extraction method, calibration curves and chromatographic conditions are common for the three matrices. Plasma and homogenized tissue samples (100 μL) were extracted with acetonitrile:formic acid mixture (99:1) (300 μL). Chromatographic separation was performed with a mixture of water and acetonitrile:methanol (50:50), both acidified with 0.5% of formic acid using a gradient profile. The method avoids the use of immunoaffinity columns and allows reduction of sample and solvent volumes as well as toxic wastes. The detection is based on a photochemical reaction which enhances the AFB1 response without affecting the OTA signal before reaching the fluorescent detector. The mycotoxin recovery for each matrix was very efficient, between 93% and 96% for AFB1 and between 94% and 96% for OTA. For both mycotoxins the LOQs were 2μg/L in plasma and 8μg/kg in liver and kidney. The method has successfully been applied to rat samples after a single oral administration of a mixture of AFB1 and OTA and it could be a useful tool in toxicokinetic and toxicological studies.  相似文献   
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