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31.
Developmental hip dysplasia (DDH) is a deformation of the locomotor system that can occur on previously normal bone structures in late fetal development. The study was undertaken to determine the value of continuous ultrasound screening in early diagnosis of DDH. In the area covered by the Labin Primary Health Center, clinical and ultrasound examination of the hips was performed in all children during the fourth month of life from 1989 to 2001. The incidence of DDH was 3.3%. The authors compared the obtained results with results of clinically examined hips in the period from 1968 to 1988 (incidence 1.7%), before the ultrasound diagnostics was introduced. The hip radiograms were performed only in children with clinically positive signs of higher degree of DHD. The ultrasound examination was performed with Hitachi EUB 410 real time linear transducer with a 5 MHz probe. The examiners used methods and criteria suggested by Graf. The most useful feature of the ultrasound method is that it allows the visualization of cartilaginous femoral head and its relationship to the acetabulum in infants. The method is non-invasive, repeatable, without risk of ionizing radiation or need for the contrast material administration. The results of the study revealed an important increase of DHD incidence after the introduction of ultrasound examination. US is highly sensitive in hip imaging and reveals the existence of a number of dislocated and subluxated hips that otherwise would be missed. The anomaly was discovered in the early period of life, which is very important for appropriate therapeutic effects.  相似文献   
32.

Key message

The olive tree response to sequential pollinations is a more accurate procedure in the assessment of effective pollination period and flower life span than procedure based on the calculation of the components of the pollen-pistil interaction.

Abstract

Effective pollination period (EPP) was defined by Williams (1965) as the period during which pollination can result in fruit set. EPP was proposed to be the time the ovules remain fertile minus the time needed for a pollen tube to reach the ovule, providing that this value does not exceed the length of stigma receptivity. The duration of the EPP in fruit trees can be estimated by the microscopic analyses of these three components, but also by the plant response to sequential pollinations in term of fruit set. Here, we compare the estimation of EPP duration under cross-pollination in the main olive cultivars (Olea europaea L.) grown for oil production in Croatia (‘Lastovka’, ‘Leccino’, and ‘Levantinka’) based on these two procedures to discuss the advantages and disadvantages of each estimation and propose the best methodology to assess EPP duration and the capacity of flowers of different age to set fruit. Our comparison highlights that the different procedures provide a contrasting duration of EPP in all olive cultivars here analyzed. EPP based on initial fruit set and final fruit set was between 2 and 3 days, while that based on the microscopic study of EPP components was between 5 and 12 days, depending on the cultivar. We defend that EPP based on fruit set is more accurate and more relevant for growers, and believe that the longer duration of EPP when the estimation is based on the study of the components could be due to wrong assessments of the duration of particular components. In this sense, pollen germination may be a better parameter than pollen adhesion to estimate stigma receptivity. Ovule longevity assessment based on the fluorescence emitted could be an overestimation of the actual ovule readiness for fertilization. Style suitability, not considered in Williams’ equation, plays an important role supporting pollen tube growth toward the ovules and might be also relevant in determining EPP duration.  相似文献   
33.
D-Ser(tBu)-L-Phe-L-Trp is described as a self-assembling tripeptide that yields nanofibrillar hydrogels at physiological conditions (phosphate buffer at pH 7.4). The peptide is characterized by several spectroscopic methods, such as circular dichroism and fluorescence, oscillatory rheometry, and transmission electron microscopy. Single-crystal X-ray diffraction reveals supramolecular packing into water-bound channels and allows the visualization of the intermolecular interactions holding together peptide stacks.  相似文献   
34.
The aim of the randomised, double blind, placebo controlled study was to evaluate the efficacy, tolerability and safety of solifenacin, a once-daily M3 selective receptor antagonist, in patients with overactive bladder syndrome. Following a single blind 2-week placebo run in period, patients who complained from symptoms of OAB for at least 6 months, were randomized to 4 weeks of solifenacin in 5 mg once daily doses or placebo. 171 patients were enrolled in the study and 157 patients completed the study. Patients with solifenacin had significantly improved micturitions per 24 hours after first week of treatment (1.75 +/- 0.63 vs. 2.64 +/- 0.48, p < 0.001), and after four weeks (1.56 +/- 0.58 vs. 2.71 +/- 0.45, p < 0.001) compared to placebo group. The mean number of urgency episodes per 24 hours had significantly decreased in patients with solifenacin compared to placebo after first week (5.75 +/- 1.43 vs. 6.65 +/- 0.65, p < 0.001), and after four weeks of treatment (5.77 +/- 1.33 vs. 6.54 +/- 0.50, p < 0.001). Solifenacin was also significantly more effective than placebo in reducing the mean number of episodes of severe urgency from baseline to end point (5.83 +/- 1.16 vs. 6.48 +/- 0.50, p < 0.001). Compared with changes obtained with placebo, episodes of urinary frequency were significanlty reduced after first week (0.3 vs. -0.5, p < 0.001) and four weeks check up periods in patients treated with solifenacin (0.19 vs. -0.15, p < 0.001). Episodes of nocturia was significantly reduced in patients treated with solifenacin after first week (0.3 vs. -0.5, p < 0.001), and after four weeks treatment period (0.45 vs. -0.50, p < 0.001). The number of incontinence episodes was also significantly decreased in solifenacin group compared to placebo group after first week (1.06 +/- 0.57 vs. 2.74 +/- 0.47, p < 0.001) and four weeks check up (0.96 +/- 0.57 vs. 2.75 +/- 0.43, p < 0.001). The most common adverse effects with solifenacin were dry mouth and constipation. Adverse effects were mild or moderate severity. The discontinuation rate owing to adverse effects was 4.5%-6.7% with solifenacin and 3.8%-6.1% with placebo, respectively. According to subjective estimation, significant improvement was achieved in 71 (92.21%) of patients treated with solifenacin and in 68 (85%) patients treated with placebo there was no change in OAB symptoms compared to baseline values. UDI score was significantly improved after solifenacin (22.26 +/- 5.91 vs. 29.61 +/- 8.45, p < 0.001) compared to placebo. IIQ score was significantly decreased in patients with solifenacin (36.25 +/- 10.34 vs. 46.86 +/- 6.81, p < 0.001) compared to placebo. In conclusion, solifenacin is a safe and effective treatment alternative for patients with overactive bladder symptoms.  相似文献   
35.
Bacterial fructansucrase enzymes belong to glycoside hydrolase family 68 and catalyze transglycosylation reactions with sucrose, resulting in the synthesis of fructooligosaccharides and/or a fructan polymer. Significant differences in fructansucrase enzyme product specificities can be observed, i.e. in the type of polymer (levan or inulin) synthesized, and in the ratio of polymer versus fructooligosaccharide synthesis. The Lactobacillus reuteri 121 inulosucrase enzyme produces a diverse range of fructooligosaccharide molecules and a minor amount of inulin polymer [with beta(2-1) linkages]. The three-dimensional structure of levansucrase (SacB) of Bacillus subtilis revealed eight amino acid residues interacting with sucrose. Sequence alignments showed that six of these eight amino acid residues, including the catalytic triad (D272, E523 and D424, inulosucrase numbering), are completely conserved in glycoside hydrolase family 68. The other three completely conserved residues are located at the -1 subsite (W271, W340 and R423). Our aim was to investigate the roles of these conserved amino acid residues in inulosucrase mutant proteins with regard to activity and product profile. Inulosucrase mutants W340N and R423H were virtually inactive, confirming the essential role of these residues in the inulosucrase active site. Inulosucrase mutants R423K and W271N were less strongly affected in activity, and displayed an altered fructooligosaccharide product pattern from sucrose, synthesizing a much lower amount of oligosaccharide and significantly more polymer. Our data show that the -1 subsite is not only important for substrate recognition and catalysis, but also plays an important role in determining the size of the products synthesized.  相似文献   
36.
Mesenchymal stromal/stem cells(MSCs) are adult stem cells of stromal origin that possess self-renewal capacity and the ability to differentiate into multiple mesodermal cell lineages. They play a critical role in tissue homeostasis and wound healing, as well as in regulating the inflammatory microenvironment through interactions with immune cells. Hence, MSCs have garnered great attention as promising candidates for tissue regeneration and cell therapy. Because the inflammatory niche plays a key role in triggering the reparative and immunomodulatory functions of MSCs, priming of MSCs with bioactive molecules has been proposed as a way to foster the therapeutic potential of these cells. In this paper, we review how soluble mediators of the inflammatory niche(cytokines and alarmins) influence the regenerative and immunomodulatory capacity of MSCs, highlighting the major advantages and concerns regarding the therapeutic potential of these inflammatory primed MSCs. The data summarized in this review may provide a significant starting point for future research on priming MSCs and establishing standardized methods for the application of preconditioned MSCs in cell therapy.  相似文献   
37.
Early development of the endemic dace Telestes karsticus is described in a Dinaric karst stream in Croatia. Larvae were acquired from successful rearing in an aquarium. Basic morphometric and meristic measures of larvae were taken during 55 days of observation. The mean total length of larvae at the time of hatching was 6.45 mm. The yolk sac was completely absorbed in all larvae by day 9 post-hatching (PH), when the mouth also opened and independent feeding and intestinal function were observed. Flexion of the urostyle was completed between days 12–16 PH. The caudal fin became completely forked on day 23 PH. Formation of fin rays was complete on day 48 PH when fish fully resembled juvenile specimens. The number of soft ray fins corresponds to the adult. Understanding the early development is particularly valuable in assessing environmental impacts and recovering of this endangered species and it is essential for effective monitoring and its conservation. This is the first report of the early development for the endemic Telestes karsticus, pointing out the importance of the obtained results for the effective conservation of the species.  相似文献   
38.
It is presented a case of a 32-year-old male with the three primary tumors diagnosed within a time period of 3 years; retroperitoneal nonseminoma in 2002, retroperitoneal mature teratoma in 2004, and metachronous testicular seminoma in 2005. We discuss the unusual presentation of these three rare events occurring in the same patient without known risk factors.  相似文献   
39.
The probiotic bacterium Lactobacillus?reuteri 121 produces two fructosyltransferase enzymes, a levansucrase and an inulosucrase. Although these two fructosyltransferase enzymes share high sequence similarity, they differ significantly in the type and size distribution of fructooligosaccharide products synthesized from sucrose, and in their activity levels. In order to examine the contribution of specific amino acids to such differences, 15 single and four multiple inulosucrase mutants were designed that affected residues that are conserved in inulosucrase enzymes, but not in levansucrase enzymes. The effects of the mutations were interpreted using the 3D structures of Bacillus?subtilis levansucrase (SacB) and Lactobacillus?johnsonii inulosucrase (InuJ). The wild-type inulosucrase synthesizes mostly fructooligosaccharides up to a degree of polymerization of 15 and relatively low amounts of inulin polymer. In contrast, wild-type levansucrase produces mainly levan polymer and fructooligosaccharides with a degree of polymerization < 5. Although most of the inulosucrase mutants in this study behaved similarly to the wild-type enzyme, the mutation G416E, at the rim of the active site pocket in loop 415-423, increased the hydrolytic activity twofold, without significantly changing the transglycosylation activity. The septuple mutant GM4 (T413K, K415R, G416E, A425P, S442N, W486L, P516L), which included two residues from the above-mentioned loop 415-423, synthesized 1-kestose only, but at low efficiency. Mutation A538S, located behind the general acid/base, increased the enzyme activity two to threefold. Mutation N543S, located adjacent to the +1/+2 sub-site residue R544, resulted in synthesis of not such a wide variety of fructooligosaccharides than the wild-type enzyme. The present study demonstrates that the product specificity of inulosucrase is easily altered by protein engineering, obtaining inulosucrase variants with higher transglycosylation specificity, higher catalytic rates and different fructooligosaccharide size distributions, without changing the β(2-1) linkage type in the product.  相似文献   
40.
The prevalence of obesity is increasing globally, and obesity is a major risk factor for metabolic diseases such as type 2 diabetes. Previously, we reported that oral administration of homobrassinolide (HB) to healthy rats triggered a selective anabolic response that was associated with lower blood glucose. Therefore, the aim of this study was to evaluate the effects of HB administration on glucose metabolism, insulin sensitivity, body composition, and gluconeogenic gene expression profiles in liver of C57BL/6J high-fat diet-induced obese mice. Acute oral administration of 50-300 mg/kg HB to obese mice resulted in a dose-dependent decrease in fasting blood glucose within 3 h of treatment. Daily chronic administration of HB (50 mg/kg for 8 wk) ameliorated hyperglycemia and improved oral glucose tolerance associated with obesity without significantly affecting body weight or body composition. These changes were accompanied by lower expression of two key gluconeogenic enzymes, phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G-6-Pase), and increased phosphorylation of AMP-activated protein kinase in the liver and muscle tissue. In vitro, HB treatment (1-15 μM) inhibited cyclic AMP-stimulated but not dexamethasone-stimulated upregulation of PEPCK and G-6-Pase mRNA levels in H4IIE rat hepatoma cells. Among a series of brassinosteroid analogs related to HB, only homocastasterone decreased glucose production in cell culture significantly. These results indicate the antidiabetic effects of brassinosteroids and begin to elucidate their putative cellular targets both in vitro and in vivo.  相似文献   
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