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101.
CZ Chang  SC Wu  CL Lin  SL Hwang  AL Kwan 《Acta neurochirurgica》2012,154(10):1877-1885

Background

Increased nuclear factor κB (NF-κB) bioexpression, as well as TNF-α, IL-1β and IL-6 levels, were observed after aneurysmal subarachnoid hemorrhage (SAH). It is of interest to investigate the effect of 6-mercaptopurine (6-mp) on cytokines/NF-κB in this SAH model.

Materials and methods

A rodent double-hemorrhage SAH model was employed. Serum and cerebrospinal fluid (CSF) samples were collected to examine IL-1, IL-6 and TNF-α levels. NF-κB subunit p65 and its inhibitor of nuclear factor κB (IκB) were examined (by Western blot). TNF-α was used to induce the phosphorylation of IκB in the presence or absence of 6-mp.

Results

Nuclear NF-κB subunit p65/IκB kinase in the basilar artery was over-expressed, and cytokines was notably increased in the SAH groups, compared with the controls (P?P?Conclusions Through inhibiting IκB bioexpression, 6-mp decreases NF-κB-related IL-1β, IL-6, and TNF-α in the presence of SAH. The study suggests 6-mp exerts vascular anti-inflammatory properties through inhibiting IκB kinase and subsequently blocks bio-activation of NF-κB and related cytokines, which may contribute to its antivasospastic effect in animals subjected to SAH.  相似文献   
102.

Background

We evaluated vascular patency and potential changes in preserved spleens after laparoscopic spleen-preserving distal pancreatectomy (SPDP) with conservation of both splenic vessels.

Methods

We retrospectively analyzed the patency of conserved splenic vessels in patients who underwent laparoscopic or robotic splenic vessel-conserving SPDP from January 2006 to August 2010. The patency of the conserved splenic vessels was evaluated by abdominal computed tomography and classified into three grades according to the degree of severity.

Results

Among 30 patients with splenic vessel-conserving laparoscopic SPDP, 29 patients with complete follow-up data were included in this study. During the follow-up period (median: 13.2?months), grades 1 and 2 splenic arterial obliteration were observed in one patient each. A total of five patients (17.2%) showed grade 1 or 2 obliteration in conserved splenic veins. Most patients (82.8%) had patent conserved splenic vein. Four patients (13.8%) eventually developed collateral venous vessels around gastric fundus and reserved spleen, but no spleen infarction was found, and none presented clinical relevant symptoms, such as variceal bleeding. There was no statistical difference in vascular patency between the laparoscopic and robotic groups (P?>?0.05).

Conclusions

Most patients showed intact vascular patency in conserved splenic vessels and no secondary changes in the preserved spleen after laparoscopic splenic vessel-conserving SPDP.  相似文献   
103.
Background/AimsThe worldwide coronavirus disease 2019 pandemic has led endoscopists to use personal protective equipment (PPE) for infection prevention. This study aimed to investigate whether wearing a face shield as PPE affects the quality of colonoscopy.MethodsWe reviewed the medical records and colonoscopy findings of patients who underwent colonoscopies at Asan Medical Center, Korea from March 10 to May 31, 2020. The colonoscopies in this study were performed by five gastroenterology fellows and four expert endoscopists. We compared colonoscopy quality indicators, such as withdrawal time, adenoma detection rate (ADR), mean number of adenomas per colonoscopy (APC), polypectomy time, and polypectomy adverse events, both before and after face shields were added as PPE on April 13, 2020.ResultsOf the 1,344 colonoscopies analyzed, 715 and 629 were performed before and after the introduction of face shields, respectively. The median withdrawal time was similar between the face shield and no-face shield groups (8.72 minutes vs 8.68 minutes, p=0.816), as was the ADR (41.5% vs 39.8%, p=0.605) and APC (0.72 vs 0.77, p=0.510). Polypectomy-associated quality indicators, such as polypectomy time and polypectomy adverse events were also not different between the groups. Quality indicators were not different between the face shield and no-face shield groups of gastroenterology fellows, or of expert endoscopists.ConclusionsColonoscopy performance was not unfavorably affected by the use of a face shield. PPE, including face shields, can be recommended without a concern about colonoscopy quality deterioration.  相似文献   
104.
Several inflammatory cytokines that promote inflammation and pathogenesis in asthma signal through the Janus kinase 1 (JAK1) pathway. This phase I, randomized, placebo‐controlled trial assessed the pharmacokinetics and safety of single and multiple ascending doses up to 15 mg twice daily for 14 days of a JAK1 inhibitor, GDC‐0214, in healthy volunteers (HVs; n = 66). Doses were administered with a dry powder, capsule‐based inhaler. An accompanying open‐label gamma scintigraphy study in HVs examined the lung deposition of a single dose of inhaled Technetium‐99m (99mTc)‐radiolabeled GDC‐0214. GDC‐0214 plasma concentrations were linear and approximately dose‐proportional after both single and multiple doses. Peak plasma concentrations occurred at 15–30 min after dosing. The mean apparent elimination half‐life ranged from 32 to 56 h across all single and multiple dose cohorts. After single and multiple doses, all adverse events were mild or moderate, and none led to treatment withdrawal. There was no clear evidence of systemic toxicity due to JAK1 inhibition, and systemic exposure was low, with plasma concentrations at least 15‐fold less than the plasma protein binding‐corrected IC50 of JAK1 at the highest dose. Scintigraphy showed that approximately 50% of the emitted dose of radiolabeled GDC‐0214 was deposited in the lungs and was distributed well to the peripheral airways. 99mTc‐radiolabeled GDC‐0214 (1 mg) exhibited a mean plasma Cmax similar to that observed in phase I at the same dose level. Overall, inhaled GDC‐0214 exhibited pharmacokinetic properties favorable for inhaled administration.

Study Highlights
  • WHAT IS THE CURRENT KNOWLEDGE ON THE TOPIC?
Many factors drive asthma pathogenesis, including several cytokines that signal through the Janus kinase 1 (JAK1) pathway. Inhibition of JAK1 is a possible target for asthma treatments, but previous studies show oral JAK1 inhibitors lead to increased risk of severe infections, malignancy and cardiovascular events.
  • WHAT QUESTION DID THIS STUDY ADDRESS?
This study investigated the safety, pharmacokinetics, and lung deposition of GDC‐0214, an inhaled JAK1 inhibitor designed to target the lungs.
  • WHAT DOES THIS STUDY ADD TO OUR KNOWLEDGE?
Inhaled delivery of a JAK inhibitor for 14 days exhibited low systemic exposure, leading to few adverse events and limited systemic toxicity, while demonstrating high deposition in the lungs.
  • HOW MIGHT THIS CHANGE CLINICAL PHARMACOLOGY OR TRANSLATIONAL SCIENCE?
Local pulmonary application of JAK inhibitors may be an effective treatment for asthma with limited systemic risks.  相似文献   
105.
BackgroundThis study aimed to examine the prognostic significance of sarcopenia combined with systemic inflammation in patients who underwent curative hepatectomy for hepatocellular carcinoma (HCC).MethodsBetween January 2010 and July 2019, we identified 159 patients with HCC who underwent curative hepatectomy at three institutional centers. We retrospectively analyzed clinicopathological outcomes, surgical outcomes, platelet lymphocyte ratio (PLR) as a systemic inflammatory marker, and computed tomography (CT)-assessed sarcopenia at the third lumbar vertebra level (L3).ResultsSarcopenia was noted in 74 (46.5%) of 159 patients and was significantly associated with male sex, low body mass index (BMI), and high PLR. In the multivariate analysis, sarcopenia [hazard ratio (HR): 2.127, P=0.026] and high PLR (HR: 1.971, P=0.038) were associated with a decrease in overall survival (OS) but not in recurrence-free survival (RFS). The combination of sarcopenia and PLR status stratified the 5-year OS into 82.0% (non-sarcopenia and a low PLR), 68.3% (sarcopenia or a high PLR), and 44.4% (sarcopenia and a high PLR) (P=0.001). In the multivariate analysis, “sarcopenia and a high PLR” and “sarcopenia or a high PLR” were revealed to be significant predictors of OS (HR: 4.300, P=0.001 and HR: 2.723, P=0.010, respectively).ConclusionsSarcopenia and high PLR were significantly associated with poor OS. The combination of these two factors may be useful for predicting survival of patients with HCC undergoing curative hepatectomy.  相似文献   
106.
Type 1 diabetes (T1D) is caused by dysregulation of the immune system in the pancreatic islets, which eventually leads to insulin-producing pancreatic β-cell death and destabilization of glucose homeostasis. One of the major characteristics of T1D pathogenesis is the production of inflammatory mediators by macrophages that result in destruction or damage of pancreatic β-cells. In this study the inflammatory microenvironment of T1D was simulated with RAW264.7 cells and MIN6 cells, acting as macrophages and pancreatic β-cells respectably. In this setting, peroxiredoxin-1, an anti-oxidant enzyme was knocked down to observe its functions in the pathogenesis of T1D. RAW264.7 cells were primed with lipopolysaccharide and co-cultured with MIN6 cells while PRX-1 was knocked down in one or both cell types. Our results suggest that hindrance of PRX-1 activity or the deficiency of this enzyme in inflammatory conditions negatively affects pancreatic β-cell survival. The observed decrease in viability of MIN6 cells seems to be caused by nitric oxide production. Additionally, it seems that PRX-1 affects previously reported protective activity of IL-6 in pancreatic β cells as well. These results signify new, undiscovered roles for PRX-1 in inflammatory conditions and may contribute toward our understanding of autoimmunity.  相似文献   
107.
Activated T cells express inhibitory receptors such as CTLA-4 that can downregulate immune responses. Blockade of or genetic deficiency in CTLA-4 can result in autoimmunity. Therefore, strategies to increase the inhibitory function of CTLA-4 may be attractive in settings of undesirable T cell responses such as autoimmunity or transplant rejection. We have tested the hypothesis that transgenic constitutive expression of CTLA-4 can further attenuate immune responses when compared with normal inducible expression. Our results indicate that transgenic expression of CTLA-4 in mouse T cells (CTLA-4-Tg T cells) results in reduced cell cycle progression and increased apoptosis of TCR-stimulated T cells. CTLA-4-Tg T cells display reduced T cell proliferation in an in vivo model of graft versus host disease (GVHD). These results further our understanding of how CTLA-4 can be manipulated to inhibit immune responses and may help development of new therapeutic strategies for clinical settings of autoimmunity and transplantation.  相似文献   
108.
109.
110.
The removal or mitigation of cyanobacterial bloom and cyanotoxins is a necessity to ensure safe drinking water and recreational water. As a feasible agent to control cyanobacterial bloom, a novel plant-mineral composite (PMC) was developed and optimized through laboratory and field testing over the past 3 years. Based on previous studies, we treated cyanobacterial bloom water (mainly Microcystis and Synechocystis) with 0.05 mg/L PMC at the small eutrophic reservoir; 2 h later, we collected samples and analyzed them in the laboratory. The intra-cellular (c-MC) and dissolved microcystin-LR (d-MC) were measured using an ELISA method. The PMC exhibited a remarkable removal of both c-MC (47.3 %) and d-MC (95.8 %) within 2 days. In addition, notable decreases (on average, 78 % of the control) in the chlorophyll-a, suspended solids, total phosphorus and biochemical oxygen demand values, in zooplankton and in the phytoplankton density (83.9 %) were verified after 48 h. These results indicate that the PMC is more effective in controlling d-MC than c-MC, suggesting a possible method to mitigate such hazardous chemicals as agrochemicals and endocrine disrupters in aquatic ecosystems.  相似文献   
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