1,111 research outputs found
Integrin-mediated membrane blebbing is dependent on the NHE1 and NCX1 activities.
Integrin-mediated signal transduction and membrane blebbing have been well studied to modulate cell adhesion, spreading and migration^1-6^. However, the relationship between membrane blebbing and integrin signaling has not been explored. Here we show that integrin-ligand interaction induces membrane blebbing and membrane permeability change. We found that sodium-proton exchanger 1 (NHE1) and sodium-calcium exchanger 1 (NCX1) are located in the membrane blebbing sites and inhibition of NHE1 disrupts membrane blebbing and decreases membrane permeability change. However, inhibition of NCX1 enhances cell blebbing to cause cell swelling which is correlated with an intracellular sodium accumulation induced by NHE17. These data suggest that sodium influx induced by NHE1 is a driving force for membrane blebbing growth, while sodium efflux induced by NCX1 in a reverse mode causes membrane blebbing retraction. Together, these data reveal a novel function of NHE1 and NCX1 in membrane permeability change and blebbing and provide the link for integrin signaling and membrane blebbing
Sixteen prescribed Chinese herbal medicines provide time-dependent cardiorenal and survival benefits in patients with overall and advanced diabetic kidney disease: a real-world study in Taiwan
BackgroundA causal connection between oxidative stress and inflammation in diabetes, along with its associated renal and cardiovascular complications, has been established. Sixteen prescribed potentially renoprotective Chinese herbal medicines for diabetic kidney disease (PRCHMDKD), which are scientific Chinese medicine (botanical drug) and categorized into five classes (clearing heat, nourishing yin, dampness dispelling, tonifying qi, and harmonizing formulas), exhibit shared antioxidative properties and target multiple oxidative stress pathways. However, the time-response, cumulative effects, and safety (hyperkalemia risk) of these sixteen PRCHMDKD on cardiorenal and survival outcomes in patients with overall and advanced DKD remain unresolved.MethodsThis retrospective cohort study analyzed national health insurance claims data in 2000–2017. Four statistical methods, including Cox proportional hazards models, complementary restricted mean survival time (RMST), propensity score matching, and competing risk analysis for end-stage renal disease (ESRD), were employed to investigate this relationship. The study included 43,480 PRCHMDKD users and an equal number of matched nonusers within the overall DKD patient population. For advanced DKD patients, the cohort comprised 1,422 PRCHMDKD users and an equivalent number of matched nonusers.ResultsPRCHMDKD use in overall and advanced, respectively, DKD patients was associated with time-dependent reductions in adjusted hazard ratios for ESRD (0.66; 95% CI, 0.61–0.70 vs. 0.81; 0.65–0.99), all-cause mortality (0.48; 0.47–0.49 vs. 0.59; 0.50–0.70), and cardiovascular mortality (0.50; 0.48–0.53 vs. 0.61; 0.45–0.82). Significant differences in RMST were observed in overall and advanced, respectively, DKD patients, favoring PRCHMDKD use: 0.31 years (95% CI, 0.24–0.38) vs. 0.61 years (0.13–1.10) for ESRD, 2.71 years (2.60–2.82) vs. 1.50 years (1.03–1.98) for all-cause mortality, and 1.18 years (1.09–1.28) vs. 0.59 years (0.22–0.95) for cardiovascular mortality. Additionally, hyperkalemia risk did not increase. These findings remained consistent despite multiple sensitivity analyses. Notably, the cumulative effects of utilizing at least four or five classes and multiple botanical drugs from the sixteen PRCHMDKD provided enhanced renoprotection for patients with both overall and advanced DKD. This suggests that there is involvement of multiple targets within the oxidative stress pathways associated with DKD.ConclusionThis real-world study suggests that using these sixteen PRCHMDKD provides time-dependent cardiorenal and survival benefits while ensuring safety for DKD patients
Synthesis and Characterization of a Photoelectrode with a Novel 3D Structure for Dye-Sensitized Solar Cells
This study designs a novel dye-sensitized solar cell (DSSC) in which the photoanode is derived from its three-dimensional (3D) structure. The inside of the cell has a positive illumination structure, with the purposes of increasing the area of photoelectrode thin film and of increasing the illuminated area within a fixed area in order to achieve the objective of enhancing the photoelectric conversion efficiency of cell. For the cell structure experiment, the study uses graphite paper, carbon and platinum as counter electrode materials, and then conducts measurement with cell heights of 3 mm, 5 mm, and 7 mm. The electrolyte used is a gel polymer electrolyte. The assembly of the cell is divided into vertical assembly, inclined assembly, and tandem assembly. In the 3D tandem cell experiment, the counter electrode material is platinum. Experimental results show that when cell height is 7 mm and illuminated area is 0.28 cm2, open-loop voltage is 0.662 V, short-circuit current density is 18.42 mA/cm2, fill factor is 0.31, and the photoelectric conversion efficiency is 3.85%, which is 1.65 times that under vertical assembly (2.34%) and 2.15 times that of the flat cell (1.79%)
Prevention and early management of carotid blowout syndrome for patients receiving head and neck salvage boron neutron capture therapy (BNCT)
Background/purpose
The incidence rate of oral and pharyngeal cancers in Taiwan has increased gradually over the past few decades. The standard treatment strategy for oral and pharyngeal cancers includes surgery or radiotherapy, with concurrent chemotherapy in certain types of tumors. Unfortunately, in-field recurrence is sometimes inexorable. Furthermore, re-irradiation of the recurrence site may cause severe complications due to the tolerance of normal tissue to radiation therapy. One fatal complication is carotid blowout syndrome (CBS). Boron neutron capture therapy (BNCT) is a new modality of radiation therapy, which is also mentioned as targeted radiotherapy. It is a feasible treatment that has the potential to spare normal tissue from being damaged by irradiation while simultaneously treating the primary tumor. In this presentation, we will share our experience with BNCT in treating recurrent head and neck cancers, as well as the prevention and management of CBS.
Materials and methods
We evaluated 4 patients with head and neck cancers treated by BNCT in Taiwan. All patients had undergone surgery previously and had received postoperative concurrent chemoradiotherapy.
Results
The 4 patients in this study were diagnosed with head and neck malignancies. The median follow-up period after the first course of BNCT was 15.1 months. After BNCT, 2 patients developed impending CBS, and 1 of them died. The remaining 3 patients survived until the last date of follow-up.
Conclusion
Pre-BNCT carotid artery evaluation through computed tomography angiography and early intervention if necessary is crucial when treating patients with recurrent head and neck cancers by BNCT
An Extract of Antrodia camphorata Mycelia Attenuates the Progression of Nephritis in Systemic Lupus Erythematosus-Prone NZB/W F1 Mice
Antrodia camphorata is used in folk medicine for the treatment of inflammation syndromes and liver-related diseases in Taiwan. The goal of this study was to evaluate the efficacy of the mycelial extract of A. camphorata (ACE) for the treatment of systemic lupus erythematosus (SLE) in SLE-prone NZB/W F1 mice. After antibodies against double-stranded DNA appeared in NZB/W mice, the mice were orally administered varying dosages of ACE (100, 200 and 400 mg kg−1) for 5 consecutive days per week for 12 weeks via gavage. To assess the efficacy of ACE, we measured SLE-associated biochemical and histopathological biomarkers levels of blood urine nitrogen (BUN), blood creatinine, urine protein and urine creatinine and thickness of the kidney glomerular basement membrane by staining with periodic acid-Schiff. Antroquinonol, an active component of ACE, was investigated for anti-inflammation activity in lipopolysaccharide-induced RAW 267.4 cells. ACE at 400 mg kg−1 significantly suppressed urine protein and serum BUN levels and decreased the thickness of the kidney glomerular basement membrane. Antroquinonol significantly inhibited the production of tumor necrosis factor-α and interleukin-1β by 75 and 78%, respectively. In conclusion, ACE reduced urine protein and creatinine levels and suppressed the thickening of the kidney glomerular basement membrane, suggesting that ACE protects the kidney from immunological damage resulting from autoimmune disease
Topographic Study of Extracted Molars with Advanced Furcation Involvement: Furcation Entrance Dimension and Molar Type
This study investigated the topography of the furcation entrance dimension (FED) on molars with advanced furcation involvement (FI). The sample pool consisted of 169 maxillary and mandibular molars from a group of 165 individuals with severely advanced periodontal destruction. The subjects included men and women aged 24 to 84 years (mean, 47.8 ± 7.2 years). The FEDs of the maxillary buccal, mesial, and distal surfaces as well as the mandibular buccal and lingual surfaces were measured under a stereomicroscope and clarified into grades I (FED < 0.55 mm), II (0.55-0.75 mm), and III (> 0.75 mm) using automatic grading system software designed by our research associates. The differences and relationships among molar location, furcation site, and FED grade were analyzed using the chi-square test. There was a significant difference among buccal (BFED), mesial (MFED), and distal (DFED) FEDs in both the maxillary first (χ24 = 58.915, p < 0.001) and second (χ24 = 66.839, p < 0.001) molars. The relationship between molar type and FED grade was statistically significant for both the BFED (p < 0.001) and the DFED (p < 0.001) of maxillary molars, as well as for both the BFED (p < 0.0001) and LFED (p < 0.0001). The difference in FED grade between the first and second molars was statistically significant in both maxillary (p < 0.001) and mandibular (p < 0.0001) molars. There was a significant relationship between FED grade and tooth location at molars with advanced FI
Invasive fungal sinusitis in patients with hematological malignancy: 15 years experience in a single university hospital in Taiwan
<p>Abstract</p> <p>Background</p> <p>Risk factors and outcomes in hematological patients who acquire invasive fungal sinusitis (IFS) are infrequently reported in the modern medical era.</p> <p>Method</p> <p>A retrospective study of hospitalized patients with hematological disease was conducted at National Taiwan University Hospital between January 1995 and December 2009.</p> <p>Results</p> <p>Clinical characteristics and outcomes with their associated radiographic and microbiological findings were analyzed. Forty-six patients with IFS and 64 patients with chronic non-invasive sinusitis were enrolled as comparsion. IFS developed more commonly in patients with acute myeloid leukemia (AML) and with prolonged neutropenia (absolute neutrophil count less than 500/mm<sup>3 </sup>for more than 10 days) (<it>p </it>< 0.001). <it>Aspergillus flavus </it>was the most common pathogen isolated (44%). Serum <it>Aspergillus </it>galactomannan antigen was elevated in seven of eleven patients (64%) with IFS caused by aspergillosis but negative for all three patients with mucormycosis. Bony erosion and extra-sinus infiltration was found in 15 of 46 (33%) patients on imaging. Overall, 19 of 46 patients (41.3%) died within 6 weeks. Patients with disease subtype of AML (p = 0.044; Odds Ratio [OR], 5.84; 95% confidence interval [95% CI], 1.02-30.56) and refractory leukemia status (p = 0.05; OR, 4.27; 95% CI, 1.003-18.15) had worse prognosis. Multivariate analysis identified surgical debridement as an independent good prognostic factor (p = 0.047) in patients with IFS.</p> <p>Conclusions</p> <p>Patients of AML with prolonged neutropenia (> 10 days) had significantly higher risk of IFS. Early introduction of anti-fungal agent and aggressive surgical debridement potentially decrease morbidity and mortality in high risk patients with IFS.</p
Phosphorylated OmpR Is Required for Type 3 Fimbriae Expression in Klebsiella pneumoniae Under Hypertonic Conditions
OmpR/EnvZ is a two-component system that senses osmotic signals and controls downstream gene expression in many species of Enterobacteriaceae. However, the role of OmpR/EnvZ in Klebsiella pneumoniae remains unknown. In this study, we found that production of MrkA, the major subunit of type 3 fimbriae, was decreased under hypertonic conditions. A deletion mutant of ompR and a site-directed mutant with a single amino acid substitution of aspartate 55 to alanine (D55A), which mimics the unphosphorylated form of OmpR, markedly reduced MrkA production under hypertonic conditions. These results indicate that K. pneumoniae type 3 fimbriae expression is activated by the phosphorylated form of OmpR (OmpR∼P). Although no typical OmpR∼P binding site was found in the PmrkA sequence, mrkA mRNA levels and PmrkA activity were decreased in the ΔompR and ompRD55A strains compared with the wild type (WT) strain, indicating that OmpR∼P mediates type 3 fimbriae expression at the transcriptional level. Previous reports have demonstrated that a cyclic-di-GMP (c-di-GMP) related gene cluster, mrkHIJ, regulates the expression of type 3 fimbriae. We found that both the ompR and ompRD55A mutants exhibited decreased mrkHIJ mRNA levels, intracellular c-di-GMP concentration, and bacterial biofilm amount, but increased total intracellular phosphodiesterase activity in response to hypertonic conditions. These results indicate that OmpR∼P regulates type 3 fimbriae expression to influence K. pneumoniae biofilm formation via MrkHIJ and modulation of intracellular c-di-GMP levels. Taken together, we herein provide evidence that OmpR∼P acts as a critical factor in the regulation of the c-di-GMP signaling pathway, type 3 fimbriae expression, and biofilm amount in K. pneumoniae in response to osmotic stresses
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