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71.
72.

Aim

The purpose of this study was to evaluate the influence of polymorphisms of the eNOS gene on the clinical status of patients with normal and high tension glaucoma.

Methods

266 Polish Caucasian patients with primary open angle glaucoma were studied. Of the 266, 156 had normal tension glaucoma (NTG) and 110 high tension glaucoma (HTG). DNA material was isolated from peripheral venous blood using commercial kits. Real-time PCR reaction was used to amplify the promoter site of the endothelial nitric oxide synthase (eNOS) gene, including the single nucleotide polymorphism (SNP) site T-786C and part of the 7th exon of eNOS, including G894T SNP. Genotypes were determined with TaqMan SNP Genotyping Assays.

Results

There were no significant differences in frequencies of the allelic variants of both polymorphisms. In G894T SNP, however, the wild GG form was more common in the HTG group. The SNP of the eNOS gene did not significantly influence the progression rate in either of the groups studied. There were no differences in variants of the eNOS gene regarding the necessity for and success of surgery and the progression of the disease. In the NTG group, no statistical correlation was observed between G894T, T786C polymorphism variants, and risk factors such as optic disc haemorrhages, optic disc notches, and peripapillary atrophy. Mean diastolic and systolic pressure during the day and night were lowest in NTG patients with the CC variant of the T786C polymorphism. No statistical correlation was observed between the G894T and T786C polymorphisms and capillaroscopic examination results.

Conclusions

Genotype frequencies are similar for both the eNOS G894T and T-786C polymorphisms in NTG and HTG patients. These polymorphisms do not correlate with risk factors and do not influence the state of the capillary system in NTG patients. Systolic blood pressure is lower in NTG patients with mutated alleles of both polymorphisms.  相似文献   
73.

Background

To determine the diagnostic efficacy of ultrasonographic malignancy risk features (UMRFs) in follicular lesions (FL) in a population with low risk of malignancy in FL and to compare it with a similar analysis in a group of patients with unequivocal cytology (UC): benign lesion (BL) or malignant neoplasm (MN).

Methods

Presence of UMRFs (hypoechogenicity, solid echostructure, taller-than-wide shape, pathological vascularization, irregular margins, microcalcifications and macrocalcifications) and their sets were assessed in 322 FL: 202 follicular lesions of undetermined significance (FLUS) and 120 suspicious for follicular neoplasm (SFN) and 300 nodules with UC: 200 BL and 100 MN, subsequently evaluated histopathologically.

Results

Cancers were confirmed in 100% nodules in MN group (89.0% of them were papillary carcinomas - PTC), in 6.4% FLUS nodules (69.2% PTC), and in 10.8% SFN nodules (30.8% PTC). In the UC group all UMRFs occurred more frequently in cancers than in benign lesions. In the FL group only calcifications were found in cancers more frequently – macro and microcalcifications together: 34.6 vs. 11.5% (p?=?0.001) and isolated macrocalcifications: 26.0 vs. 6.8% (p?=?0.001); the presence of those features increased the basic risk of malignancy in FL more than 2 times. The presence of at least 2 of the following URMFs: hypoechogenicity, solid echostructure, any type of calcifications and suspected shape, additionally improved sensitivity.

Conclusions

Evaluation of UMRFs in FLs is less effective than in nodules with UC, and its effectiveness decreases parallel to the decrease in percentage of PTCs among malignant neoplasms and to the increase of the percentage of adenomas among benign nodules. The presence of macrocalcifications in such FLs significantly increases the basic risk of malignancy in these nodules.
  相似文献   
74.
75.
The establishment of proper kinetochore-microtubule attachments facilitates faithful chromosome segregation. Incorrect attachments activate the spindle assembly checkpoint (SAC), which blocks anaphase onset via recruitment of a cohort of SAC components (Mph1/MPS1, Mad1, Mad2, Mad3/BubR1, Bub1 and Bub3) to kinetochores. KNL1, a component of the outer kinetochore KMN network (KNL1/Mis12 complex/Ndc80 complex), acts as a platform for Bub1 and Bub3 localization upon its phosphorylation by Mph1/MPS1. The Ndc80 protein, a major microtubule-binding site, is critical for MPS1 localization to the kinetochores in mammalian cells. Here we characterized the newly isolated mutant ndc80-AK01 in fission yeast, which contains a single point mutation within the hairpin region. This hairpin connects the preceding calponin-homology domain with the coiled-coil region. ndc80-AK01 was hypersensitive to microtubule depolymerizing reagents with no apparent growth defects without drugs. Subsequent analyses indicated that ndc80-AK01 is defective in SAC signaling, as mutant cells proceeded into lethal cell division in the absence of microtubules. Under mitotic arrest conditions, all SAC components (Ark1/Aurora B, Mph1, Bub1, Bub3, Mad3, Mad2 and Mad1) did not localize to the kinetochore. Further genetic analyses indicated that the Ndc80 hairpin region might act as a platform for the kinetochore recruitment of Mph1, which is one of the most upstream SAC components in the hierarchy. Intriguingly, artificial tethering of Mph1 to the kinetochore fully restored checkpoint signaling in ndc80-AK01 cells, further substantiating the notion that Ndc80 is a kinetochore platform for Mph1. The hairpin region of Ndc80, therefore, plays a critical role in kinetochore recruitment of Mph1.  相似文献   
76.
77.
Epilepsy, one of the most frequent neurological disorders, is still insufficiently treated in about 30% of patients. As a consequence, identification of novel anticonvulsant agents is an important issue in medicinal chemistry. In the present article we report synthesis, physicochemical, and pharmacological evaluation of N‐trans‐cinnamoyl derivatives of R and S‐2‐aminopropan‐1‐ol, as well as R and S‐2‐aminobutan‐1‐ol. The structures were confirmed by spectroscopy and for derivatives of 2‐aminopropan‐1‐ols the configuration was evaluated by means of crystallography. The investigated compounds were tested in rodent models of seizures: maximal electroshock (MES) and subcutaneous pentetrazol test (scPTZ), and also in a rodent model of epileptogenesis: pilocarpine‐induced status prevention. Additionally, derivatives of 2‐aminopropan‐1‐ols were tested in benzodiazepine‐resistant electrographic status epilepticus rat model as well as in vitro for inhibition of isoenzymes of cytochrome P450. All of the tested compounds showed promising anticonvulsant activity in MES. For R(–)‐(2E)‐N‐(1‐hydroxypropan‐2‐yl)‐3‐phenylprop‐2‐enamide pharmacological parameters were found as follows: ED50 = 76.7 (68.2–81.3) mg/kg (MES, mice i.p., time = 0.5 h), ED50 = 127.2 (102.1–157.9) mg/kg (scPTZ, mice i.p., time = 0.25 h), TD50 = 208.3 (151.4–230.6) mg/kg (rotarod, mice i.p., time = 0.25 h). Evaluation in pilocarpine status prevention proved that all of the reported compounds reduced spontaneous seizure activity and act as antiepileptogenic agents. Both enantiomers of 2‐aminopropan‐1‐ols did not influence cytochrome P450 isoenzymes activity in vitro and are likely not to interact with CYP substrates in vivo. Chirality 28:482–488, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   
78.
We investigated the effects of several tree species on dehydrogenase and urease activities in soils derived from two different parent materials (glaciofluvial sand and loess) in forested areas in southern Poland. We hypothesized that coniferous forests (pine, spruce) alter the soil cation exchange capacity (CEC) and decrease soil pH and, therefore, might decrease soil enzyme activities compared with broadleaf species growing on similar soils. Eight paired plots (12 × 12 m) were established on glaciofluvial sand in pine (Pinus sylvestris) + oak (Quercus robur) and spruce (Picea abies) + pine stands, as well as on loess-derived soils: beech (Fagus sylvatica) + pine and hornbeam (Carpinus betulus) + pine stands. Each plot was a 4 × 4 m grid with 16 sampling points. In soil samples pH, soil texture, and organic carbon, nitrogen, base cation contents, dehydrogenase and urease activities were determined. On both parent materials, the soil pH was lower under coniferous species than under broadleaf species. The acidifying effect of tree species on sandy soil was in the order of spruce = pine > oak, while that on loess was pine > beech > hornbeam. Hornbeam and oak increased the soil pH and stimulated enzyme activity in the soil. The content of fine fraction enhanced potential enzyme activities in soils, thus the loess soils had greater dehydrogenase and urease activity. The results suggest that pine stores more soil organic C in association with silt increasing the pool of stabilized soil organic C.  相似文献   
79.
Interactions between ecological communities of herbivores and microbes are commonly mediated by a shared plant. A tripartite interaction between a pathogenic fungus-host plant-herbivorous insect is an example of such mutual influences. In such a system a fungal pathogen commonly has a negative influence on the morphology and biochemistry of the host plant, with consequences for insect herbivore performance. Here we studied whether the biotrophic fbngus Podosphaera ferruginea, attacking the great burnet Sanguisorba officinalis, affects caterpillar performance of the endangered scarce large blue butterfly Phengaris teleius. Our results showed that the pathogenic ftmgus affected the number and size of inflorescences produced by food-plants and, more importantly, had in direct, plant-mediated effects on the abun dance, body mass and immune response of caterpillars. Specifically, we found the relationship between caterpillar abundance and variability in inflorescence size on a plant to be positive among healthy food-plants, and negative among infected food-plants. Caterpillars that fed on healthy food-plants were smaller than those that fed on infected food-plants in one studied season, while there was no such difference in the other season. We observed the relationship between caterpillar immune response and the proportion of infected great burnets within a habitat patch to be positive when caterpillars fed on healthy food-plants, and negative when caterpillars fed on infected food-plants. Our results suggest that this biotrophic fungal infection of the great burnet may impose a significant indirect influence on P. teleius caterpillar performance with potential consequences for the population dynamics and structure of this endangered butterfly.  相似文献   
80.
AimThe aim of the study was to assess the accuracy of radiological diagnosis of laryngeal cartilage infiltration by histopathological examination of laryngeal specimen after total laryngectomy.BackgroundDespite the development of new medical technologies and significant clinical advances allowing early diagnosis and treatment of laryngeal cancer, mortality is still on the rise. Neoplastic infiltration of the laryngeal cartilages is the most common source of error in the assessment of cancer staging. Furthermore, cartilage invasion is listed as a contraindication to partial surgical techniques as well as radiotherapy.Materials and methodsThe study was carried out on 21 larynges following total laryngectomy. Before taking the decision to perform surgery, high-resolution CT scans were performed in all cases. An extended histopathological examination was conducted using a unique vertical cross-section of the whole larynx.ResultsPathology reported 2 cases of arytenoid cartilage invasion, 5 cases of cricoid cartilage invasion, 12 cases of thyroid cartilage penetration, 1 case of internal cortex invasion and 9 cases of extra-laryngeal spread. CT imaging identified 8 of 13 cases (61.5%) of pathologically proven invasion of thyroid cartilage and only 2 cases (2/9, 22%) of extra-laryngeal spread. According to CT results, arytenoid cartilage invasion was correctly identified in 2 cases, cricoid cartilage invasion in 4 (4/5, 80%). The positive predictive values for thyroid, cricoid and arytenoid cartilage invasion and penetration were 80%, 66.7% and 50%, respectively. In case of pre-laryngeal spread the positive predictive value was 100%.ConclusionDespite increasingly advanced methods involved in the diagnosis of laryngeal cancer, many discrepancies may be observed between the radiological and histopathological assessments. CT imaging has limitations especially in thyroid cartilage penetration and extra-laryngeal spread assessment in advanced laryngeal cancer cases. An extended histopathological examination, involving vertical cross-sections of the whole larynx is a very precise study that allows a precise determination of local cancer staging (T).  相似文献   
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