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Inflammation in the liver is an extraintestinal manifestation that is frequently seen during inflammatory bowel diseases (IBD). The authors investigated histopathologycal, ultrastructural and antioxidant effects of dexmedetomidine (Dex) on liver during trinitrobenzene sulfonic acid (TNBS)-induced inflammatory bowel disease. Thirty-two BALB/c mice were divided (n?=?8) as follows: control; Dex (dexmedetomidine) (30?μg/kg) for 6 days; TNBS 150?μL, TNBS?+?ethanol (50% w/v) intrarectally; TNBS?+?Dex. The histopathological and ultrastructural changes were evaluated. The levels of malondialdehyde (MDA), activity of antioxidant enzymes (GPx and SOD) were measured in liver tissue. Induction of colitis induced histopathological and ultrastructural changes of damage in liver. Those changes were markedly reduced in the TNBS?+?Dex group and that reduction was even significant in comparison to the TNBS group. MDA levels were significantly higher in the TNBS group and dexmedetomidine significantly elevated SOD levels in the TNBS?+?Dex group. These results suggest that the administration of dexmedetomidine reduces the histopathological and ultrastructural damage and increases the defense capacity against oxidative damage on liver in this IBD mice model.  相似文献   
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Beyond its impact on bone health, numerous studies have investigated the immune-regulatory properties of vitamin D and shown how its deficiency can affect outcomes in allogeneic hematopoietic stem cell transplantation (HSCT), particularly in acute or chronic graft-versus-host disease. This survey, carried out by the Transplant Complications Working Party of the European Society for Blood and Marrow Transplantation (EBMT), describes the current clinical practice discrepancies across the EBMT HSCT programs. We therefore recommend the development of evidence-based guidelines to standardize evaluation criteria and to harmonize the management of vitamin D deficiency in patients undergoing allogeneic HSCT.  相似文献   
5.
The main purpose of this study is to establish an effective cryopreservation protocol for the umbilical cord tissue as a source of mesenchymal stem cells (MSCs). In this context, it was aimed to use a cryoprotectant that could be an alternative to dimethyl sulfoxide (DMSO) which is commonly used despite the toxic side effects. Therefore, two different cryopreservation solutions were prepared using 10% DMSO and 10% 1,2 propanediol (PrOH). The fresh tissue group that was not performed cryopreservation was used as the control group. Following the cryopreservation step, MSCs were isolated from all groups and compared with each other to assess the efficiency of the cryopreservation solutions. The comparison was performed in terms of followings: morphology, immunophenotypes, growth kinetics, differentiation, and ultrastructural features. Based on the results, there were no significant morphological and immunophenotypic differences between the MSCs isolated from cryopreserved tissue groups and the MSCs isolated from the fresh tissue group. According to the growth kinetic analysis, the cells isolated from the PrOH group had a lower proliferation rate than the cells isolated from the fresh tissue. However, there was no significant difference between the cryopreserved groups in this respect. Osteogenic and adipogenic differentiation was observed in all groups. Upon comparison of the cryopreserved groups, PrOH group was discovered to hold a minor superiority in terms of these modes of differentiation. These results suggest that PrOH, which is considered as a cryoprotectant with low toxicity, could be used as a preferred cryoprotectant instead of DMSO concerning the process of cryopreservation of the umbilical cord.  相似文献   
6.
Etch-and-rinse adhesives can cause vasorelaxation via mechanisms occurring in the endothelium and smooth muscle, including the release of nitric oxide (NO). This effect might promote or aggravate bleeding if such adhesives are placed inadvertently on iatrogenic pulp microexposures. The present study assessed the vasoactive potential of a newer generation self-etch adhesive, Clearfil Protect Bond (CPB), on isolated rat aorta. Cumulative concentrations of the primer, bond, and mixture of CPB elicited concentration-dependent relaxation of phenylephrine-induced active tonus in the rat aorta, demonstrating that the tested self-etch adhesive can lead to vasorelaxation of pulp vessels that is mediated by Ca(2+) antagonistic effect. The vasorelaxant effect of CPB or its components was mediated neither via endothelium-dependent NO and prostanoid-dependent mechanisms nor by K(+) efflux through K(+) channels. Mechanical removal of the endothelium did not significantly alter the relaxation induced by CPB. Assuming these data can be extrapolated to the clinical situation, CPB, either in mixed form or by its components, can lead to vasorelaxation of pulp vessels that is mediated by a Ca(2+) antagonistic effect. If CPB is placed inadvertently on pulp microexposures during direct pulp capping, this effect might promote bleeding that might impair healing and, via plasma exatravasation, might compromise resin infiltration and polymerization.  相似文献   
7.
This study investigated the effects of 18β-glycyrrhetinic acid (GA) on neuronal damage in brain tissue caused by global cerebral ischemia/reperfusion (I/R) in C57BL/J6 mice. All subjects (n = 40) were equally divided into four groups: (1) sham-operated (SH), (2) I/R, (3) GA, and (4) GA+I/R. The SH group was used as a control. In the I/R group, the bilateral carotid arteries were clipped for 15 min, and the mice were treated with the vehicle for 10 days. In the GA group, mice were given GA (100 mg/kg) for 10 days following a median incision without carotid occlusion. In the GA+I/R group, the I/R model was applied to the mice exactly as in the I/R group, and they were then treated with the same dose of GA for 10 days. Cerebral I/R significantly induced oxidative stress via an increase in lipid peroxidaitons and a decrease in elements of the antioxidant defense systems. However, GA treatment was protective against the oxidative effects of I/R by inducing significant increases in antioxidant defense systems and a significant decrease of lipid peroxidations. Additionally, cerebral I/R increased the incidence of histopathological damage and apoptosis in brain tissue, but these neurodegenerative effects were eliminated by GA treatment. Therefore, the current study demonstrated that GA treatment effectively prevents oxidative and histological damage in the brain caused by global I/R. In this context, GA may be useful for the attenuation of the negative effects of global cerebral I/R and, in the future, it may be a viable and safe alternative treatment for ischemic stroke in humans.  相似文献   
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Graefe's Archive for Clinical and Experimental Ophthalmology - Microscale droplets act as coronaviruses (CoV) carriers in the air when released from an infected person and may infect others...  相似文献   
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OBJECTIVE: The role of psychological factors related to headache has long been a focus of investigation. The aim of this study was to evaluate depression, automatic thoughts, alexithymia, and assertiveness in persons with tension-type headache and to compare the results with those from healthy controls. METHODS: One hundred five subjects with tension-type headache (according to the criteria of the International Headache Society classification) and 70 controls were studied. The Beck Depression Inventory, Automatic Thoughts Scale, Toronto Alexithymia Scale, and Rathus Assertiveness Schedule were administered to both groups. Sociodemographic variables and headache features were evaluated via a semistructured scale. RESULTS: Compared with healthy controls, the subjects with headache had significantly higher scores on measures of depression, automatic thoughts, and alexithymia and lower scores on assertiveness. Subjects with chronic tension-type headache had higher depression and automatic thoughts scores than those with episodic tension-type headache. CONCLUSIONS: These findings suggested that persons with tension-type headache have high depression scores and also may have difficulty with expression of their emotions. Headache frequency appears to influence the likelihood of coexisting depression.  相似文献   
10.

Background

Partial internal biliary diversion (PIBD) is an alternative approach for the treatment of devastating pruritus in patients with progressive familial intrahepatic cholestasis (PFIC). In these patients quality of life can be improved and progression of liver disease can be delayed while waiting for liver transplantation. The aim of our study was to evaluate six patients with PFIC who have undergone PIBD in long-term follow-up.

Methods

Retrospective review of the records of six patients who underwent PIBD for PFIC between 2008 and 2010 was conducted to evaluate age, growth, clinical and laboratory studies for long-term outcome.

Results

Serum postoperative bile acid levels were reduced from a mean 340.1 μmol/L (range 851–105) preoperatively to a mean of 96.3 μmol/L at postoperative fifth year. The difference between pre- and postoperative bile acid levels was statistically significant (p = 0.018). AST decreased from 79.1 U/L (range 43–150 U/L) to 64.6 U/L (range 18–172 U/L), ALT decreased from 102.8 U/L (range 35-270 U/L) to 84.6 U/L and total bilirubin decreased from 2.9 μmol/L (range 0.35–6.4 μmol/L) to 1.53 μmol/L (range 0.3–2.4). Again, the decrease in total bilirubin levels was significant (p = 0.043). Pruritus was diminished from a mean of + 4 (range 4–4) preoperatively to a mean of + 2 (4–0). One patient who underwent liver transplantation owing to relapsing pruritus died from postoperative sepsis in the early postoperative period at the fifth year after PBID. Five symptom-free patients have not required liver transplantation at a mean period of 6.1 ± 0.83 years (5.1–7.0 years) follow-up.

Conclusion

PBID is an effective surgical procedure in the long-term and can delay the need for liver transplantation in children with PFIC by reducing jaundice and pruritus.  相似文献   
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