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21.
Site selective mono‐ and dimetalation methods have been developed for the functionalization of 1‐[(1,1′‐biphenyl)‐2‐yl]‐1H‐pyrrole. Optical resolution of the prepared 1‐[(3‐carboxy‐1,1′‐biphenyl)‐2‐yl]pyrrole‐2‐carboxylic acid provided new atropisomeric 1‐arylpyrrole derivatives. The absolute configuration of the pure dicarboxylic acid enantiomers was determined by single crystal X‐ray diffraction and CD spectroscopy. Chirality 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
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In the last decades, several expeditions were organized in Europe by the researchers of the Hungarian Natural History Museum to collect snails, aquatic insects and soil animals (mites, springtails, nematodes, and earthworms). In this study, scale insect (Hemiptera: Coccomorpha) specimens extracted from Hungarian Natural History Museum soil samples (2970 samples in total), all of which were collected using soil and litter sampling devices, and extracted by Berlese funnel, were examined. From these samples, 43 scale insect species (Acanthococcidae 4, Coccidae 2, Micrococcidae 1, Ortheziidae 7, Pseudococcidae 21, Putoidae 1 and Rhizoecidae 7) were found in 16 European countries. In addition, a new species belonging to the family Pseudococcidae, Brevennia larvalis Kaydan, sp. n. and a new species of Ortheziidae, Ortheziola editae Szita & Konczné Benedicty, sp. n. are described and illustrated based on the adult female stage. Revised keys to the adult females of Brevennia and Ortheziola are presented.  相似文献   
24.
In the period 1971 to 1976, 200 non-cholera vibrio (NCV) strains were isolated in Hungary; 18 of the cultures were derived from 34 729 faecal and 182 from 237 surface water samples. Ninety-two strains belonged to the Heiberg-Smith group I and 108 to group II. Two strains failed to give the string test and 3 were pteridine resistant. The strains were classified into 48 serotypes according to Smith's system. Faecal NCV strains belonged to serotypes 46 and 328; these serotypes did not occur in water. Of the 18 faecal strains 13 were isolated from 18 048 persons who had travelled in cholera-infected areas, and 5 strains from persons who had never left Hungary (2 from 4559 patients with diarrhoea and 3 from 6061 healthy individuals). These data indicate that although NCV are present in the environment, they play an insignificant role in enteric infections in Hungary.  相似文献   
25.
Monitoring and control of pH is essential for the control of reaction conditions and reaction progress for any biocatalytic or biotechnological process. Microfluidic enzymatic reactors are increasingly proposed for process development, however typically lack instrumentation, such as pH monitoring. We present a microfluidic side‐entry reactor (μSER) and demonstrate for the first time real‐time pH monitoring of the progression of an enzymatic reaction in a microfluidic reactor as a first step towards achieving pH control. Two different types of optical pH sensors were integrated at several positions in the reactor channel which enabled pH monitoring between pH 3.5 and pH 8.5, thus a broader range than typically reported. The sensors withstood the thermal bonding temperatures typical of microfluidic device fabrication. Additionally, fluidic inputs along the reaction channel were implemented to adjust the pH of the reaction. Time‐course profiles of pH were recorded for a transketolase and a penicillin G acylase catalyzed reaction. Without pH adjustment, the former showed a pH increase of 1 pH unit and the latter a pH decrease of about 2.5 pH units. With pH adjustment, the pH drop of the penicillin G acylase catalyzed reaction was significantly attenuated, the reaction condition kept at a pH suitable for the operation of the enzyme, and the product yield increased. This contribution represents a further step towards fully instrumented and controlled microfluidic reactors for biocatalytic process development.  相似文献   
26.

Background

Pericardial fluid (PF) contains several biologically active substances, which may provide information regarding the cardiac conditions. Nitric oxide (NO) has been implicated in cardiac remodeling. We hypothesized that L-arginine (L-Arg) precursor of NO-synthase (NOS) and asymmetric dimethylarginine (ADMA), an inhibitor of NOS, are present in PF of cardiac patients and their altered levels may contribute to altered cardiac morphology.

Methods

L-Arg and ADMA concentrations in plasma and PF, and echocardiographic parameters of patients undergoing coronary artery bypass graft (CABG, n = 28) or valve replacement (VR, n = 25) were determined.

Results

We have found LV hypertrophy in 35.7% of CABG, and 80% of VR patients. In all groups, plasma and PF L-Arg levels were higher than that of ADMA. Plasma L-Arg level was higher in CABG than VR (75.7±4.6 μmol/L vs. 58.1±4.9 μmol/L, p = 0.011), whereas PF ADMA level was higher in VR than CABG (0.9±0.0 μmol/L vs. 0.7±0.0 μmol/L, p = 0.009). L-Arg/ADMA ratio was lower in the VR than CABG (VRplasma: 76.1±6.6 vs. CABGplasma: 125.4±10.7, p = 0.004; VRPF: 81.7±4.8 vs. CABGPF: 110.4±7.2, p = 0.009). There was a positive correlation between plasma L-Arg and ADMA in CABG (r = 0.539, p = 0.015); and plasma and PF L-Arg in CABG (r = 0.357, p = 0.031); and plasma and PF ADMA in VR (r = 0.529, p = 0.003); and PF L-Arg and ADMA in both CABG and VR (CABG: r = 0.468, p = 0.006; VR: r = 0.371, p = 0.034). The following echocardiographic parameters were higher in VR compared to CABG: interventricular septum (14.7±0.5 mm vs. 11.9±0.4 mm, p = 0.000); posterior wall thickness (12.6±0.3 mm vs. 11.5±0.2 mm, p = 0.000); left ventricular (LV) mass (318.6±23.5 g vs. 234.6±12.3 g, p = 0.007); right ventricular (RV) (33.9±0.9 cm2 vs. 29.7±0.7 cm2, p = 0.004); right atrial (18.6±1.0 cm2 vs. 15.4±0.6 cm2, p = 0.020); left atrial (19.8±1.0 cm2 vs. 16.9±0.6 cm2, p = 0.033) areas. There was a positive correlation between plasma ADMA and RV area (r = 0.453, p = 0.011); PF ADMA and end-diastolic (r = 0.434, p = 0.015) and systolic diameter of LV (r = 0.487, p = 0.007); and negative correlation between PF ADMA and LV ejection fraction (r = -0.445, p = 0.013) in VR.

Conclusion

We suggest that elevated levels of ADMA in the PF of patients indicate upregulated RAS and reduced bioavailability of NO, which can contribute to the development of cardiac hypertrophy and remodeling.  相似文献   
27.
The capacity of milli and micro litre bioreactors to accelerate process development has been successfully demonstrated in traditional biotechnology. However, for regenerative medicine present smaller scale culture methods cannot cope with the wide range of processing variables that need to be evaluated. Existing microfabricated culture devices, which could test different culture variables with a minimum amount of resources (e.g. expensive culture medium), are typically not designed with process development in mind. We present a novel, autoclavable, and microfabricated scale-down device designed for regenerative medicine process development. The microfabricated device contains a re-sealable culture chamber that facilitates use of standard culture protocols, creating a link with traditional small-scale culture devices for validation and scale-up studies. Further, the modular design can easily accommodate investigation of different culture substrate/extra-cellular matrix combinations. Inactivated mouse embryonic fibroblasts (iMEF) and human embryonic stem cell (hESC) colonies were successfully seeded on gelatine-coated tissue culture polystyrene (TC-PS) using standard static seeding protocols. The microfluidic chip included in the device offers precise and accurate control over the culture medium flow rate and resulting shear stresses in the device. Cells were cultured for two days with media perfused at 300 µl.h−1 resulting in a modelled shear stress of 1.1×10−4 Pa. Following perfusion, hESC colonies stained positively for different pluripotency markers and retained an undifferentiated morphology. An image processing algorithm was developed which permits quantification of co-cultured colony-forming cells from phase contrast microscope images. hESC colony sizes were quantified against the background of the feeder cells (iMEF) in less than 45 seconds for high-resolution images, which will permit real-time monitoring of culture progress in future experiments. The presented device is a first step to harness the advantages of microfluidics for regenerative medicine process development.  相似文献   
28.
Pregnant women were examined following healthy pregnancies at term. Amniotic fluids were sampled before arteficial rupture of membranes using closed vacutainer system. Blood samples were also taken from the pregnants simultaneously. Endotoxin concentrations of amniotic fluids were tested by the semiquantitative Limulus amebocyte lysate. Both amniotic fluids and blood samples were tested for the presence of DNA of lymphotropic human herpesviruses. The DNA of human papillomaviruses were tested only in the amniotic fluid samples. One-third of the amniotic fluids tested were found to contain measurable amounts of endotoxin. Lymphotropic herpesvirus DNA was deteced in every fourth amniotic fluid sample and in every 8th blood sample. The prevalence of papillomaviruses was 7 of 96 samples. No significant correlation was found between the presence of endotoxin and viruses in the amniotic fluids. Epstein-Barr virus, human cytomegalovirus and human herpesvirus type 7 were found more frequently in the amniotic fluids than in blood samples (7 to 1). The prevalence of human herpesvirus 6 and 8 was higher in the blood samples than that in the amniotic fluids. The mean weight of the neonates were not impaired significantly by the presence of either viruses or endotoxin. Possible post partum consequences, i.e. partial immunotolerance to viruses is discussed.  相似文献   
29.
Pituitary adenylate cyclase activating polypeptide (PACAP) is present in the cranial arteries and trigeminal sensory neurons. We therefore examined the alterations in PACAP-like immunoreactivity (PACAP-LI) in a time-dependent manner in two rat models of trigeminovascular system (TS) activation. In one group chemical stimulation (CS) was performed with i.p. nitroglycerol (NTG), and in the other one the trigeminal ganglia (TRG) were subjected to electrical stimulation (ES). The two biologically active forms, PACAP-38 and PACAP-27, were determined by means of radioimmunoassay (RIA) and mass spectrometry (MS) in the plasma, the cerebrospinal fluid (CSF), the trigeminal nucleus caudalis (TNC), the spinal cord (SC) and the TRG. The tissue concentrations of PACAP-27 were 10 times lower than those of PACAP-38 in the TNC and SC, but about half in the TRG. PACAP-38, but not PACAP-27, was present in the plasma. Neither form could be identified in the CSF. PACAP-38-LI in the plasma, SC and TRG remained unchanged after CS, but it was increased significantly in the TNC 90 and 180 min after NTG injection. In response to ES of the TRG, the level of PACAP-38 in the plasma and the TNC was significantly elevated 90 and 180 min later, but not in the SC or the TRG. The alterations in the levels of PACAP-27 in the tissue homogenates in response to both forms of stimulation were identical to those of PACAP-38. The selective increases in both forms of PACAP in the TNC suggest its important role in the central sensitization involved in migraine-like headache.  相似文献   
30.
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