978 resultados para Alpha-(bedt-ttf)(2)mhg(scn)(4)
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Tubulo-interstitial fibrosis is a constant feature of chronic renal failure and it is suspected to contribute importantly to the deterioration of renal function. In the fibrotic kidney there exists, besides normal fibroblasts, a large population of myofibroblasts, which are supposedly responsible for the increased production of intercellular matrix. It has been proposed that myofibroblasts in chronic renal failure originate from the transformation of tubular cells via epithelial-mesenchymal transition (EMT) or from infiltration by bone marrow-derived precursors. Little attention has been paid to the possibility of a transformation of resident fibroblasts into myofibroblasts in renal fibrosis. Therefore we examined the fate of resident fibroblasts in the initial phase of renal fibrosis in the classical model of unilateral ureter obstruction (UUO) in the rat. Rats were perfusion-fixed on days 1, 2, 3 and 4 after ligature of the right ureter. Starting from 1 day of UUO an increasing expression of alpha-smooth muscle actin (alphaSMA) in resident fibroblasts was revealed by immunofluorescence and confirmed by the observation of bundles of microfilaments and webs of intermediate filaments in the electron microscope. Inversely, there was a decreased expression of 5'-nucleotidase (5'NT), a marker of renal cortical fibroblasts. The RER became more voluminous, suggesting an increased synthesis of matrix. Intercellular junctions, a characteristic feature of myofibroblasts, became more frequent. The mitotic activity in fibroblasts was strongly increased. Renal tubules underwent severe regressive changes but the cells retained their epithelial characteristics and there was no sign of EMT. In conclusion, after ureter ligature, resident peritubular fibroblasts proliferated and they showed progressive alterations, suggesting a transformation in myofibroblasts. Thus the resident fibroblasts likely play a central role in fibrosis in that model.
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Beneficial effects by both interferon-beta and statin treatment in patients with multiple sclerosis (MS) may be linked to interference with the Th1/Th2 cytokine balance. We determined patterns of Th1/Th2 cytokines (interleukin (IL)-1beta, IL-2, IL-6, IL-12p70, tumor-necrosis factor (TNF)-alpha and interferon-gamma, and IL-4, IL-5 and IL-10, respectively) in the serum of patients with relapsing-remitting MS treated with 250microg interferon-beta 1b or with interferon-beta plus 40mg atorvastatin. In treatment naïve patients with MS, a trend for lower TNF-alpha serum levels compared to controls was detected (P=0.08). Interferon-beta treatment increased TNF-alpha levels, while a trend for lowering of IL-5 serum levels was found (P=0.07). Addition of atorvastatin raised IL-12p70 serum levels (P<0.05). Mean levels of two Th2 cytokines (IL-4, IL-10) showed a non-significant increase after addition of atorvastatin. We conclude that interferon-beta and atorvastatin exert divergent action on Th1/Th2 serum cytokines levels in MS. Supplemental atorvastatin might promote a Th1-type response by raising IL-12p70. Further studies are required to support a Th2 cytokine shift by atorvastatin in patients with MS.
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BACKGROUND: The aim of this study was to determine the performance of a new, 3D-monitor based, objective stereotest in children under the age of four. METHODS: Random-dot circles (diameter 10 cm, crossed, disparity of 0.34 degrees) randomly changing their position were presented on an 3D-monitor while eye movements were monitored by infrared photo-oculography. If > or = 3 consecutive stimuli were seen, a positive response was assumed. One hundred thirty-four normal children aged 2 months to 4 years (average 17+/-15.3 months) were examined. RESULTS: Below the age of 12 months, we were not able to obtain a response to the 3D stimulus. For older children the following rates of positive responses were found: 12-18 months 25%, 18-24 months 10%, 24-30 months 16%, 30-36 months 57%, 36-42 months 100%, and 42-48 months 91%. Multiple linear logistic regression showed a significant influence on stimulus recognition of the explanatory variables age (p<0.00001) and child cooperation (p<0.001), but not of gender (p>0.1). CONCLUSIONS: This 3D-monitor based stereotest allows an objective measurement of random-dot stereopsis in younger children. It might open new ways to screen children for visual abnormalities and to study the development of stereovision. However, the current experimental setting does not allow determining random-dot stereopsis in children younger than 12 months.
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OBJECTIVE: The burnout syndrome has been associated with an increased risk of cardiovascular disease. The physiological mechanisms potentially involved in this link are underexplored. Knowing that a chronic low-grade systemic inflammatory state contributes to atherosclerosis, we investigated circulating cytokine levels in relation to burnout symptoms. METHODS: We studied 167 schoolteachers (median, 48 years; range, 23-63 years; 67% women) who completed the Maslach Burnout Inventory with its three subscales emotional exhaustion (EE), lack of accomplishment (LA), and depersonalization (DP). Levels of the proinflammatory cytokine tumor necrosis factor (TNF)-alpha and of the anti-inflammatory cytokines interleukin (IL)-4 and IL-10 were determined in fasting morning plasma samples. The TNF-alpha/IL-4 ratio and the TNF-alpha/IL-10 ratio were computed as two indices of increased inflammatory activity. Analyses were adjusted for demographic factors, medication, lifestyle factors (including sleep quality), metabolic factors, and symptoms of depression and anxiety. RESULTS: Higher levels of total burnout symptoms aggregating the EE, LA, and DP subscales independently predicted higher TNF-alpha levels (DeltaR(2)=.024, P=.046), lower IL-4 levels (DeltaR(2)=.021, P=.061), and a higher TNF-alpha/IL-4 ratio (DeltaR(2)=.040, P=.008). Higher levels of LA predicted decreased IL-4 levels (DeltaR(2)=.041, P=.008) and a higher TNF-alpha/IL-4 ratio (DeltaR(2)=.041, P=.007). The categorical dimensions of the various burnout scales (e.g., burnout yes vs. no) showed no independent relationship with any cytokine measure. CONCLUSION: Burnout was associated with increased systemic inflammation along a continuum of symptom severity rather than categorically. Given that low-grade systemic inflammation promotes atherosclerosis, our findings may provide one explanation for the increased cardiovascular risk previously observed in burned-out individuals.
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Leukocyte transmigration is mediated by endothelial cell (EC) junctional molecules, but the associated mechanisms remain unclear. Here we investigate how intercellular adhesion molecule-2 (ICAM-2), junctional adhesion molecule-A (JAM-A), and platelet endothelial cell adhesion molecule (PECAM-1) mediate neutrophil transmigration in a stimulus-dependent manner (eg, as induced by interleukin-1beta [IL-1beta] but not tumor necrosis factor-alpha [TNF-alpha]), and demonstrate their ability to act in sequence. Using a cell-transfer technique, transmigration responses of wild-type and TNF-alpha p55/p75 receptor-deficient leukocytes (TNFR(-/-)) through mouse cremasteric venules were quantified by fluorescence intravital microscopy. Whereas wild-type leukocytes showed a normal transmigration response to TNF-alpha in ICAM-2(-/-), JAM-A(-/-), and PECAM-1(-/-) recipient mice, TNFR(-/-) leukocytes exhibited a reduced transmigration response. Hence, when the ability of TNF-alpha to directly stimulate neutrophils is blocked, TNF-alpha-induced neutrophil transmigration is rendered dependent on ICAM-2, JAM-A, and PECAM-1, suggesting that the stimulus-dependent role of these molecules is governed by the target cell being activated. Furthermore, analysis of the site of arrest of neutrophils in inflamed tissues from ICAM-2(-/-), JAM-A(-/-), and PECAM-1(-/-) mice demonstrated that these molecules act sequentially to mediate transmigration. Collectively, the findings provide novel insights into the mechanisms of action of key molecules implicated in leukocyte transmigration.
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Various new oral hypoglycaemic agents have been developed recently and have changed the therapy of type 2 diabetes mellitus. Six different classes of agents are available: Biguanides, sulfonylureas, glinides, glitazones, alpha-glucosidase inhibitors and dipeptidyl peptidase-4 inhibitors. The increasing number of these drugs does not facilitate the choice of the best medication for an individual patient. In the article we describe the specific mechanisms of action, side effects, advantages and disadvantages of the different agents. Every drug therapy should be supported by lifestyle changes. Despite all the new drugs type 2 diabetes is still a chronic and slowly progressive disease without chance of cure. Therefore, it is important to prevent type 2 diabetes by normalizing body weight and increasing physical exercise.
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Insect bite hypersensitivity (IBH) is an allergic dermatitis of horses caused by bites of Culicoides and sometimes Simulium spp. The aim of this investigation was to identify Simulium allergens associated with IBH. A phage surface display cDNA library expressing recombinant Simulium vittatum salivary gland proteins was screened using sera of IBH-affected horses sensitized to S. vittatum salivary gland proteins as shown in immunoblot, resulting in the identification of seven cDNAs encoding IgE-binding proteins. The deduced amino acid sequences of these proteins showed sequence similarities to antigen 5 like protein (Sim v 1), to a serine protease inhibitor (Sim v 2), to two alpha-amylases (Sim v 3 and Sim v 4), and to three S. vittatum erythema proteins (SVEPs). The cDNA inserts were subcloned and expressed as [His](6)-tagged protein in Escherichia coli and purified using Ni(2+)-chelate affinity chromatography. Mice were immunised with the seven recombinant proteins and the antibodies tested against the recombinant proteins and salivary gland extract (SGE) of S. vittatum and Culicoides nubeculosus in immunoblot analyses. r-Sim v 1 specific mouse Abs recognized a band of about 32 kDa in immunoblots of both S. vittatum and C. nubeculosus SGE, detectable also by serum IgE of IBH-affected horses. Preincubation of horse serum with r-Sim v 1 completely inhibited IgE binding to the 32 kDa band demonstrating the presence of cross-reactive antigen 5 like proteins in both SGE. Determination of IgE levels against the r-Sim v proteins and crude S. vittatum extract by ELISA in sera from 25 IBH-affected and 20 control horses showed that IBH-affected horses had significantly higher IgE levels than controls against r-Sim v 1, 2, 3, 4 and S. vittatum extract, whereas the r-SVEP showed only marginal IgE binding. Further analyses showed that 60% of IBH-affected horses reacted to r-Sim v 1, suggesting that this could be a major allergen for IBH. Forty to twenty percent of the IBH-affected horses reacted with r-Sim v 2, 3 or 4. Combination of the results obtained with the 4 r-Sim v proteins showed that 92% of the IBH-affected but only 15% of the healthy horses had IgE levels against one or more of the 4 r-Sim v proteins. Seventy percent of the healthy horses had detectable IgE against S. vittatum extract, indicating a low specificity of the detection system used. Optimization of the ELISA system will be required to determine reliable cut-off values for the IBH-related allergens. Their in vivo relevance needs to be carefully assessed.
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INTRODUCTION To what extent haematocrit levels (Hct) and platelet counts (PLT) influence the measurement of parameters of thromboelastometry when assessed with the ROTEM® device is unclear. We investigated to what extent thromboelastometry measurements depend on Hct and PLT. MATERIALS AND METHODS Whole blood samples were taken for in-vitro preparations of mixtures with three different levels of PLT and a varying Hct. Maximum clot firmness (MCF), clotting time (CT), clot formation time (CFT) and alpha angle (α) for INTEM, EXTEM, FIBTEM and APTEM was recorded. RESULTS Measurements depended substantially on Hct and PLT. MCF readings were systematically lower with increasing Hct (0.2 vs. 0.4: -7.8 (-8.3 to -7.2); p<0.001, 0.2 vs. 0.55: -14.5 (-17.3 to -14.3); p<0.001) but higher with increasing PLT (50 vs. 125×10(9)/l: 8.2 (4.2 to 12.3); p=0.005, 50 vs. 250×10(9)/l: 12.0 (7.2 to 16.8); p=0.002). CT readings were systematically higher with increasing Hct (0.2 vs. 0.4: 9.2 (6.2 to 12.1); p=0.001, 0.2 vs. 0.55: 38.2 (21.5 to 54.9); p=0.003) while increasing PLT had no influence. CFT readings were also systematically higher with increasing Hct (0.2 vs. 0.4: 83.8 (40.2 to 127.6); p=0.006, 0.2 vs. 0.55: 226.2 (110.7 to 341.7); p=0.006) but systematically lower with increasing PLT (50 vs. 125×10(9)/l: -144.0 (-272.3 to -15.6); p=0.036, 50 vs. 250×10(9)/l: -189.2 (-330.4 to -48.0); p=0.02); readings of the alpha angle showed a similar pattern. CONCLUSIONS Our results suggest that readings of thromboelastometry parameters need to be adjusted by Hct and PLT to avoid potential confounding and miss-interpretations in clinical practice.
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Daunorubicin (DNR) is an anthracycline antibiotic used as a cancer chemotherapeutic agent. However, it causes mammary adenocarcinomas in female Sprague-Dawley (SD) rats. Vitamin E (E) has been found to reduce DNR carcinogenicity. I investigated the mechanism of DNR carcinogenicity and its interaction with E in SD rats by studying DNR-DNA adduct formation and the influence of E status on DNR clearance and free radical producing and detoxifying enzymes.^ The hypothesis was that DNR exerts its tumorigenic effect via free radicals generated during redox cycling and production of reactive intermediates capable of forming DNA adducts. E was postulated to act as a protective agent through a combination of its antioxidant property, modulation of drug clearance and levels of free radical producing and detoxifying enzymes.^ DNA adduct formation was measured by the nuclease P1 $\sp{32}$P-post labeling assay. In vitro, DNR was activated by rat liver microsomes and either NADPH or cumene hydrogen peroxide (CuOOH). Rat liver DNA incubated with this mixture formed two adducts when the cofactor was NADPH and three adducts when CuOOH was used. In vivo, SD rats were treated with i.v. doses of DNR. No detectable DNR-DNA adducts were formed in liver or mammary DNA in vivo, although there was an intensification of endogenous DNA adducts.^ Groups, 1, 2, 3 and 4 of weanling female SD rats were fed 0, 100, 1,000 and 10,000 mg $\alpha$-tocopheryl acetate/kg diet respectively. A comparison of Groups 1 and 4 showed no effect of E status on clearance of 10 mg tritiated DNR/kg body weight over 72 hours. However, liver cleared DNR at a faster rate than mammary epithelial cells (MEC).^ Xanthine oxidase, which catalyzes DNR redox cycling, was significantly decreased in liver and MEC of rats in group 4 compared to groups 1, 2, and 3. Detoxifying enzymes were not dramatically affected by E supplementation. Quinone reductase in MEC was significantly increased in group 4 compared to other groups. Overall, the liver had higher levels of free radical detoxifying enzymes compared to MEC.^ These data support a role of free radicals in DNR carcinogenicity because (1) endogenous DNA adducts formed due to free radical insult are further intensified by DNR treatment in vivo, (2) MEC, the specific target of DNR carcinogenicity, cannot rapidly clear DNR and have a lower free radical detoxifying capability than liver, (3) E supplementation caused lowering of free radical generating potential via xanthine oxidase, and increased DNR detoxification due to elevation of quinone reductase in MEC. ^
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Objective: Since the beginning of the integrated care model for severely ill patients with psychotic disorders ("Hamburg model") in 2007 different clinical parameters have been consecutively assessed within a naturalistic, observational, prospective study.Methods: Clinical outcome of the 2-year and 4-year follow-ups of n = 158 patients.Results: A significant and ongoing improvement of psychopathology, severity of illness, functional outcome, quality of life and satisfaction with care in this sample of severely ill and merely chronic patients with psychosis was shown. Moreover, medication adherence improved and quality and quantity of outpatient treatment increased.Conclusion: The ongoing psychosocial stabilisation of the patients most likely result from a combination of various factors: continuity of care, multimodal and individualized care, therapeutic specialisation and the multidisciplinary ACT team. Results provide clinical and scientific evidence for future implementations of the integrated care model "Hamburg Model" for the treatment of psychosis.
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Rolandic epilepsy (RE) is the most common idiopathic focal childhood epilepsy. Its molecular basis is largely unknown and a complex genetic etiology is assumed in the majority of affected individuals. The present study tested whether six large recurrent copy number variants at 1q21, 15q11.2, 15q13.3, 16p11.2, 16p13.11 and 22q11.2 previously associated with neurodevelopmental disorders also increase risk of RE. Our association analyses revealed a significant excess of the 600 kb genomic duplication at the 16p11.2 locus (chr16: 29.5-30.1 Mb) in 393 unrelated patients with typical (n = 339) and atypical (ARE; n = 54) RE compared with the prevalence in 65,046 European population controls (5/393 cases versus 32/65,046 controls; Fisher's exact test P = 2.83 × 10(-6), odds ratio = 26.2, 95% confidence interval: 7.9-68.2). In contrast, the 16p11.2 duplication was not detected in 1738 European epilepsy patients with either temporal lobe epilepsy (n = 330) and genetic generalized epilepsies (n = 1408), suggesting a selective enrichment of the 16p11.2 duplication in idiopathic focal childhood epilepsies (Fisher's exact test P = 2.1 × 10(-4)). In a subsequent screen among children carrying the 16p11.2 600 kb rearrangement we identified three patients with RE-spectrum epilepsies in 117 duplication carriers (2.6%) but none in 202 carriers of the reciprocal deletion. Our results suggest that the 16p11.2 duplication represents a significant genetic risk factor for typical and atypical RE.
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We present the first direct measurement of neutral oxygen in the lunar exosphere, detected by the Chandrayaan-1 Energetic Neutral Analyzer (CENA). With the lunar surface consisting of about 60% of oxygen in number, the neutral oxygen detected in CENA's energy range (11 eV−3.3 keV) is attributed to have originated from the lunar surface, where it was released through solar wind ion sputtering. Fitting of CENA's mass spectra with calibration spectra from ground and in-flight data resulted in the detection of a robust oxygen signal, with a flux of 0.2 to 0.4 times the flux of backscattered hydrogen, depending on the solar wind helium content and particle velocity. For the two solar wind types observed, we derive subsolar surface oxygen atom densities of N0= (1.1 ± 0.3) · 107m−3 and (1.4 ± 0.4) · 107m−3, respectively, which agree well with earlier model predictions and measured upper limits. From these surface densities, we derive column densities of NC= (1.5 ± 0.5) · 1013 m−2and (1.6 ± 0.5) · 1013 m−2. In addition, we identified for the first time a helium component. This helium is attributed to backscattering of solar wind helium (alpha particles) from the lunar surface as neutral energetic helium atoms, which has also been observed for the first time. This identification is supported by the characteristic energy of the measured helium atoms, which is roughly 4 times the energy of reflected solar wind hydrogen, and the correlation with solar wind helium content.
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di Georgio Philippo Telemann
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Cefepime is frequently prescribed to treat infections caused by AmpC-producing Gram-negative bacteria. CMY-2 is the most common plasmid-mediated AmpC (pAmpC) β-lactamase. Unfortunately, CMY variants conferring enhanced cefepime resistance are reported. Here, we describe the evolution of CMY-2 to an extended-spectrum AmpC (ESAC) in clonally identical E. coli isolates obtained from a patient. The CMY-2-producing E. coli (CMY-2-Ec) was isolated from a wound. Thirty days later, one CMY-33-producing E. coli (CMY-33-Ec) was detected in bronchoalveolar lavage. Two weeks before the isolation of CMY-33-Ec, the patient received cefepime.CMY-33-Ec and CMY-2-Ec were identical by rep-PCR, being of hyperepidemic ST131, but showed different β-lactam MICs (e.g., cefepime 16 vs. ≤0.5 μg/ml). Identical CMY-2-Ec isolates were also found in a rectal swab. CMY-33 differs from CMY-2 by a Leu293-Ala294 deletion. Expressed in E. coli DH10B, both CMYs conferred resistance to ceftazidime (≥256 μg/ml), but cefepime MICs were higher for CMY-33 than CMY-2 (8 vs. 0.25 μg/ml). The kcat/Km or kinact/KI (μM(-1) s(-1)) indicated that CMY-33 possesses an ESBL-like spectrum compared to CMY-2 (cefoxitin: 0.2 vs. 0.4; ceftazidime: 0.2 vs. not measurable; cefepime: 0.2 vs. not measurable; tazobactam 0.0018 vs. 0.0009). Using molecular modeling, we show that a widened active site (∼4 Å shift) may play a significant role in enhancing cefepime hydrolysis. This is the first in vivo demonstration of a pAmpC that under cephalosporin treatment expands its substrate spectrum resembling an ESBL. The prevalence of CMY-2-Ec isolates is rapidly increasing worldwide, therefore awareness that cefepime treatment may select for resistant isolates is critical.
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In monocotyledonous plants, 1,4-benzoxazin-3-ones, also referred to as benzoxazinoids or hydroxamic acids, are one of the most important chemical barriers against herbivores. However, knowledge about their behavior after attack, mode of action and potential detoxification by specialized insects remains limited. We chose an innovative analytical approach to understand the role of maize 1,4-benzoxazin-3-ones in plant–insect interactions. By combining unbiased metabolomics screening and simultaneous measurements of living and digested plant tissue, we created a quantitative dynamic map of 1,4-benzoxazin-3-ones at the plant–insect interface. Hypotheses derived from this map were tested by specifically developed in vitro assays using purified 1,4-benzoxazin-3-ones and active extracts from mutant plants lacking 1,4-benzoxazin-3-ones. Our data show that maize plants possess a two-step defensive system that effectively fends off both the generalist Spodoptera littoralis and the specialist Spodoptera frugiperda. In the first step, upon insect attack, large quantities of 2-β-d-glucopyranosyloxy-4,7-dimethoxy-1,4-benzoxazin-3-one (HDMBOA-Glc) are formed. In the second step, after tissue disruption by the herbivores, highly unstable 2-hydroxy-4,7-dimethoxy-1,4-benzoxazin-3-one (HDMBOA) is released by plant-derived β-glucosidases. HDMBOA acts as a strong deterrent to both S. littoralis and S. frugiperda. Although constitutively produced 1,4-benzoxazin-3-ones such as 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one (DIMBOA) are detoxified via glycosylation by the insects, no conjugation of HDMBOA in the insect gut was found, which may explain why even the specialist S. frugiperda has not evolved immunity against this plant defense. Taken together, our results show the benefit of using a plant–insect interface approach to elucidate plant defensive processes and unravel a potent resistance mechanism in maize.