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51.
The carbonate production event in the Moravian part of the Carpathian Foredeep is known as a deposition of a carbonate–siliciclastic complex in the marginal part of the basin, correlating with the time period from the last occurrence of Helicosphaera waltrans (14.36 Ma) to the last occurrence of Sphenolithus heteromorphus (13.34 Ma). Sedimentological and microfacial data, analysis of foraminifera, calcareous nannoplankton, red algae, mollusks, palynology, as well as oxygen and carbon stable isotopes from foraminiferal tests, were used to interpret the specific paleoenvironment of the carbonate production event. The event was accelerated by a decrease of terrigenous input due to a large transgression and, primarily, an increasingly arid climate. Production of carbonate was related to oligotrophic conditions, expansion of sea-grass meadows, summer downwelling circulations and winter stratification of the water column. Autochthonous and semi-autochthonous carbonates were deposited in shallow-water near the fair-weather wave-base; allochthonous carbonates were transported to the outer shelf by gravity flows. Climatic instability and relative sea-level changes, induced mainly by substantial tectonic activity, caused the carbonate bodies to be small with a high ratio of siliciclastic components, indicating only a short-term and spatially restricted environment suitable for carbonate production. Exceptionally, carbonate production persisted longer during the whole sea-level cycle (“Rousínov Ridge”). Siliciclastic intercalations in these larger limestone bodies represent catastrophic rain events that transported a higher amount of terrigenous material into the basin. The specific climatic conditions of the carbonate production event, namely climatic instability and aridification with episodic intensive rain, were associated with the Middle Miocene climatic transition in the study area.  相似文献   
52.
The pathogenesis of nasal polyps is not completely understood. Oxidative damage contributes to polyp formation in the nasal mucosa. The paraoxonase 1 (PON1) enzyme is an important liver enzyme with high antioxidant activity. In this study, we investigated the correlation between Q192R genotypic polymorphism of the PON1 enzyme and nasal‐polyp disease. The study examined 62 nasal‐polyp patients and 88 controls. PON1 Q192R polymorphism was determined using polymerase chain reaction‐restriction fragment length polymorphism. The genotype distribution of the PON1 gene was significantly different between nasal‐polyp patients (QQ = 69.35%, QR = 25.81%, RR = 4.83%) and healthy controls (QQ = 52.27%, QR = 44.31%, RR = 3.40%). Our results suggest that the PON1 QQ genotype (odds ratio [OR] = 2.066, P = .036) is associated with a higher risk of developing the nasal‐polyp disease while QR genotype (OR = 0.437, P = .021) showed a lower risk.  相似文献   
53.
AimsThis study investigates the effects of vagus nerve stimulation (VNS) on seizure severity and blood–brain barrier (BBB) integrity in kindled rats with cortical dysplasia (CD).Main methodsPregnant rats were exposed to 145 cGy of gamma-irradiation on day 17 of pregnancy. In offsprings, kindling was induced by giving subconvulsive doses of pentylenetetrazole. Left VNS was performed for 48 h at output currents of 0.5 or 1 mA. Horseradish peroxidase (HRP) was used to study the BBB permeability. Immunohistochemistry for occludin and P-glycoprotein (P-gp) was also performed.Key findingsKindled rats with CD exhibited seizures with mean Racine's scores of 3.57 ± 1.2 during video EEG recording. Kindled animals with CD receiving VNS at 0.5 and 1.0 mA did not exhibit either clinical or electrophysiological signs of seizure. Immunostaining for occludin, a tight junction protein, in hippocampus remained relatively intact in all groups. VNS-treated and -untreated kindled animals with CD revealed intense immunostaining for P-gp in hippocampal formation (P < 0.01). Electron microscopic observations revealed frequent transport vesicles containing electron-dense HRP reaction products in the cytoplasm of brain capillary endothelial cells in both cerebral cortex and hippocampus of kindled animals with CD. Those which were exposed to 1 mA VNS were observed to have brain capillary endothelial cells largely devoid of HRP reaction products in both cerebral cortex and hippocampus.SignificanceThe results of this study suggest that VNS therapy at 1 mA inhibits seizure activity and protects BBB integrity by limiting the enhancement of transcellular pathway in kindled animals with CD.  相似文献   
54.
Therapy‐induced senescence is a state of cell cycle arrest that occurs as a response to various chemotherapeutic reagents, especially ones that cause DNA damage. Senescent cells display resistance to cell death and can impair the efficacy of chemotherapeutic strategies. Since lipids can exhibit pro‐survival activity, it is envisioned in this article that probing the lipidome could provide insights into novel lipids that are involved in senescence. Therefore, a tissue culture model system is established and the cellular lipidomes of senescent and proliferating cells are comparatively analyzed. Out of thousands of features detected, 17 species are identified that show significant changes in senescent cells. The majority of these species (11 out of 17) are atypical sphingolipids, 1‐deoxyceramides/dihydroceramides, which are produced as a result of the utilization of alanine, instead of serine during sphingolipid biosynthesis. These lipids are depleted in senescent cells. Elevating the levels of deoxyceramides by supplementing the growth medium with metabolic precursors or by directly adding deoxyceramide result in decreased senescence, suggesting that these species might play a key role in this process.  相似文献   
55.
The present report describes a case with the triad of yellow nail syndrome (YNS) and the use of low-pressure compression pump as treatment of lymphedema in YNS. A 71-year-old woman presented with bilateral lower extremity lymphedema, yellow nails, and recurrent bilateral pleural effusion. In this case, we specifically focused on lymphedema treatment of the legs besides other recommendations for YNS.  相似文献   
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57.
Endotoxin decreases mesenteric blood flow and inflicts organ injury via free radicals. We investigated whether taurine, an endogenous antioxidant and vasodilator, could attenuate the deleterious effects of endotoxin in a mouse model of sepsis. Swiss albino mice were allocated into four groups and treated either with taurine (150 mg/kg, i.p. at 0(th), 8(th), 16(th) h) or its solvent sterile saline (NaCl 0.9%, w/v) while E. coli endotoxin (20 mg/kg, i.p.) or its solvent saline were also given at 8(th) h. At 24(th) h the animals were anaesthetized and the mesenteric blood flow was measured by using perivascular ultrasonic Doppler-flowmeter. The animals were then exsanguinated, the spleen, liver, and kidneys were isolated for histopathological examination. Thiobarbituric acid-reacting substances (TBARS), glutathione, and myeloperoxidase activity were determined in the liver samples. Endotoxin significantly decreased the mesenteric blood flow and glutathione levels in liver while TBARS and myeloperoxidase activity were increased. However, taurine did not block the deleterious effects of endotoxin nor it did attenuate the histopathological injury. Therefore, we concluded that endotoxin-induced organ injury via free radicals is resistant to blockade by taurine.  相似文献   
58.
Objective: A recent study suggested that high concentrations of leptin enhance platelet aggregations. Therefore, the aim of this study was to investigate whether platelet aggregation is altered in patients with leptin gene mutations compared with obese subjects or controls. Research Methods and Procedures: Four men (one homozygous man and his three heterozygous brothers) carrying a leptin gene mutation; 20 age‐matched, healthy, unrelated men; and 18 age‐matched obese men were enrolled in the study. Adenosine diphosphate (ADP)‐, collagen‐, and epinephrine‐induced platelet aggregation were evaluated in all individuals. Results: Our results show that patients with the leptin gene mutation (both the homozygous and heterozygous patients) had significantly higher ADP‐induced (78.3 ± 3.4% vs. 57.9 ± 9.3%, p = 0.001), collagen‐induced (78.1 ± 2.9% vs. 56.7 ± 9.3%, p = 0.007), and epinephrine‐induced (76.5 ± 9.2% vs. 59.5 ± 7.70%, p = 0.003) platelet aggregation compared with controls. However, ADP‐, collagen‐, or epinephrine‐induced platelet aggregations were similar to those in obese patients. Platelet aggregation responses to a combination of pretreatment with leptin at concentrations of 20, 50, 100, or 500 ng/mL for 5 minutes and ADP at concentrations of 2 μmol/liter also were evaluated. However, we did not find significant increases in platelet aggregation even at high concentrations of leptin (100 or 500 ng/mL) in leptin‐deficient patients, obese subjects, or controls. Discussion: Our data show that similar to findings in obese humans, homozygous or heterozygous leptin deficiency is associated with increased platelet aggregation compared with controls, and that higher concentrations of leptin do not increase platelet aggregation.  相似文献   
59.
In this study, the effects of kaolin (M-99-099) applications on the total phenolic and antioxidant contents of tea leaves (Camellia sinensis (L.) O. Kuntze) harvested in three different periods were investigated. For this purpose, four different strategies including standard fertilizer application (T), 3% kaolin+standard fertilizer application (Ka1), 6% kaolin+standard fertilizer application (Ka2), and control (C) (nothing applied) were used to compare the effects of these strategies on total phenolic content, FRAP values, and DPPH radical scavenging capacities of tea leaves. It has been proven that the kaolin applications, Ka1 and Ka2, increase the phenolic content and antioxidant contents of tea samples. While the kaolin applications have higher values at 1st harvest than those of T and C, they have the lowest values at 3rd harvest.  相似文献   
60.
BackgroundExercise is associated with major benefits in patients with rheumatic diseases for both cardiovascular and rheumatic status. However, information about exercise generally is not collected systematically in routine rheumatology care. A multidimensional health assessment questionnaire (MDHAQ), which was designed for busy clinical settings, includes a query about exercise status. We analyzed possible associations between change in MDHAQ exercise scores and other MDHAQ measures in patients with various rheumatic diseases over one year.MethodsIn one rheumatology clinical setting, all patients, regardless of diagnosis, complete an MDHAQ before seeing a rheumatologist. The MDHAQ includes scores for physical function, pain, and patient global estimate, compiled into an index, routine assessment of patient index data (RAPID3), as well as a self-report joint count and a query about exercise. Patients were classified into four groups according to their exercise status at baseline and one year later as: EXER-Yes (regular exercise), EXER-Yes; EXER-No (no regular exercise), EXER-Yes; EXER-Yes, EXER-No; and EXER-No, EXER-No. These groups were compared using the chi square and Kruskal-Wallis tests and analysis of variance (ANOVA).ResultsPatients who reported regular exercise at baseline were younger, had higher formal education, and better clinical status than other patients. The EXER-No, EXER-Yes group had greater improvement in other MDHAQ variables than patients in the other three groups. By contrast, the EXER-Yes, EXER-No group was the only group with poorer status one year later.ConclusionsThe MDHAQ exercise query indicates that regular exercise is associated with better clinical status. Patients in the EXER-No, EXER-Yes group reported the best clinical improvement, although it is not known whether exercise preceded or followed the improved clinical status.  相似文献   
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