Acetylation-mediated proteasomal degradation of core histones during DNA repair and spermatogenesis.

Histone acetylation plays critical roles in chromatin remodeling, DNA repair, and epigenetic regulation of gene expression, but the underlying mechanisms are unclear. Proteasomes usually catalyze ATP- and polyubiquitin-dependent proteolysis. Here, we show that the proteasomes containing the activator PA200 catalyze the polyubiquitin-independent degradation of histones. Most proteasomes in mammalian testes ("spermatoproteasomes") contain a spermatid/sperm-specific α subunit α4 s/PSMA8 and/or the catalytic ß subunits of immunoproteasomes in addition to PA200. Deletion of PA200 in mice abolishes acetylation-dependent degradation of somatic core histones during DNA double-strand breaks and delays core histone disappearance in elongated spermatids. Purified PA200 greatly promotes ATP-independent proteasomal degradation of the acetylated core histones, but not polyubiquitinated proteins. Furthermore, acetylation on histones is required for their binding to the bromodomain-like regions in PA200 and its yeast ortholog, Blm10. Thus, PA200/Blm10 specifically targets the core histones for acetylation-mediated degradation by proteasomes, providing mechanisms by which acetylation regulates histone degradation, DNA repair, and spermatogenesis.

Typical value ranges and signal patterns in patients with neurogenic bladder: Quality control in urodynamics using an air-charged catheter system.

PURPOSE: To establish typical value ranges (TVRs) of the air-charged catheter (ACC) system, and analyze the typical signal patterns (TSPs) of cough under different bladder volumes for quality control of a urodynamic study using the ACC system. MATERIALS AND METHODS: The urodynamic traces of 1977 patients with neurogenic bladder (NB) were analyzed for intravesical pressure (pves ), abdominal pressure (pabd ), and detrusor pressure (pdet ) in the cough test at our center from July 2017 to December 2021. The pdet cough signals were described and classified. The pdet cough signal patterns in different bladder volumes and postures were analyzed. RESULTS: The 50% range of the initial resting pves , pabd , and pdet in the supine and sitting positions were 7-15, 7-14, and 0-0 cmH2 O, and 24-33, 24-33, and 0-0 cmH2 O, respectively. The cough amplitudes for pves and pabd were similar in the 50% range, as follows: 10-27 and 8-25 cmH2 O in the supine position, respectively; and 18-43 and 17-40 cmH2 O in the sitting position, respectively. The cough amplitude of pves and pabd was not related to bladder volume (p > 0.05). The cough spikes of pdet were divided into three types: type I, in which pdet has a minimal change (<5 cmH2 O); type II, a monophasic cough spike, in which could be a positive (IIa, ≥5 cmH2 O) or negative spike (IIb, ≥5 cmH2 O); and type III, a biphasic spike, in which could be a positive-to-negative biphasic (IIIa) or negative-to-positive spike (IIIb). Under different bladder volumes, the cough signals of pdet were all expressed as type I, II, or III, and the cough signals were unrelated to bladder volume (p > 0.05). CONCLUSIONS: TVRs of the initial resting state in patients with NB were established to provide guidance for quantitative quality control of the ACC system. The TSPs of the pdet cough signal under different bladder volume and posture were described, which could be used for qualitative quality control of the ACC system.

Quercetin Treatment Improves Renal Function and Protects the Kidney in a Rat Model of Adenine-Induced Chronic Kidney Disease.

BACKGROUND The aim of this study was to examine the effects of the natural flavonoid, quercetin, in a rat model of adenine-induced chronic kidney disease. MATERIAL AND METHODS Forty male Wister rats were divided into four groups: normal (no adenine or quercetin) (n=10); untreated model (treated withadenine but not quercetin) (n=10); quercetin-treated model (5 mg/kg/day for 21 days) (n=10); quercetin-treated model (10 mg/kg/day for 21 days) (n=10). Urine and blood samples were collected and rat kidneys were examined histologically. RESULTS Comparison of the findings of the model rats treated with quercetin (n=20) with non-treated model rats (n=10) showed reduced levels of fibroblast growth factor 23 (FGF23): normal group, 19.6 pg/ml; untreated group, 73.6 pg/ml; quercetin-treated group (5 mg/kg), 34.25 pg/ml; and quercetin-treated group (10 mg/kg), 21.3 pg/ml. Quercetin-treated model rats had reduced serum levels of parathyroid hormone (PTH), inorganic phosphate, increased urine protein-to-creatinine ratio, increased urine antioxidants, serum lactate dehydrogenase (LDH), and interleukin (IL)-8 when compared with the untreated model group and the control group. Quercetin treatment 10 mg/kg (n=10) reduced the levels of creatinine, blood urea nitrogen (BUN), and urinary uric acid. Renal histopathology in model rats treated with quercetin (n=20) showed reduced inflammation compared with the untreated model rats (n=10). CONCLUSIONS In a rat model of adenine-induced chronic kidney disease, treatment with quercetin improved renal function, reduced oxidative stress factors, serum levels of FGF23, and kidney inflammation.

Increased Eps15 homology domain 1 and RAB11FIP3 expression regulate breast cancer progression via promoting epithelial growth factor receptor recycling.

Recent research indicates that the C-terminal Eps15 homology domain 1 is associated with epithelial growth factor receptor-mediated endocytosis recycling in non-small-cell lung cancer. The aim of this study was to determine the clinical significance of Eps15 homology domain 1 gene expression in relation to phosphorylation of epithelial growth factor receptor expression in patients with breast cancer. Primary breast cancer samples from 306 patients were analyzed for Eps15 homology domain 1, RAB11FIP3, and phosphorylation of epithelial growth factor receptor expression via immunohistochemistry. The clinical significance was assessed via a multivariate Cox regression analysis, Kaplan-Meier curves, and the log-rank test. Eps15 homology domain 1 and phosphorylation of epithelial growth factor receptor were upregulated in 60.46% (185/306) and 53.92% (165/306) of tumor tissues, respectively, as assessed by immunohistochemistry. The statistical correlation analysis indicated that Eps15 homology domain 1 overexpression was positively correlated with the increases in phosphorylation of epithelial growth factor receptor ( r = 0.242, p < 0.001) and RAB11FIP3 ( r = 0.165, p = 0.005) expression. The multivariate Cox proportional hazard model analysis demonstrated that the expression of Eps15 homology domain 1 alone is a significant prognostic marker of breast cancer for the overall survival in the total, chemotherapy, and human epidermal growth factor receptor 2 (-) groups. However, the use of combined expression of Eps15 homology domain 1 and phosphorylation of epithelial growth factor receptor markers is more effective for the disease-free survival in the overall population, chemotherapy, and human epidermal growth factor receptor 2 (-) groups. Moreover, the combined markers are also significant prognostic markers of breast cancer in the human epidermal growth factor receptor 2 (+), estrogen receptor (+), and estrogen receptor (-) groups. Eps15 homology domain 1 has a tumor suppressor function, and the combined marker of Eps15 homology domain 1/phosphorylation of epithelial growth factor receptor expression was identified as a better prognostic marker in breast cancer diagnosis. Furthermore, RAB11FIP3 combines with Eps15 homology domain 1 to promote the endocytosis recycling of phosphorylation of epithelial growth factor receptor.

A computational study of self-assembled hexapeptide inhibitors against amyloid-ß (Aß) aggregation.

The fibrillation and deposition of amyloid-ß (Aß) peptides in human brains are pathologically linked to Alzheimer's disease (AD). Development of different inhibitors (peptides, organic molecules, and nanoparticles) to prevent Aß aggregation becomes a promising therapeutic strategy for AD treatment. We recently propose a "like-interacts-like" design principle to computationally design/screen and experimentally validate a new set of hexapeptide inhibitors with completely different sequences from the Aß sequence. These hexapeptide inhibitors inhibit Aß aggregation and reduce Aß-induced cytotoxicity. However, inhibitory mechanisms of these hexapeptides and the underlying interactions between hexapeptides and Aß remain unclear. Herein we apply multi-scale computational methods (quantum-chemical calculations, molecular docking and explicit-solvent molecular dynamic simulation) to explore the structure, dynamics, and interaction between 3 identified hexapeptides (CTLWWG, GTVWWG, and CTIYWG) and different Aß-derived fragments and an Aß17-42 pentamer. When interacting with 6 Aß-derived fragments, 3 hexapeptide inhibitors show stronger interactions with two lysine-included fragments (16KLVFFA21 and 27NKGAII33) than other fragments, indicating different sequence-specific interactions with Aß. When interacting with the Aß17-42 pentamer, the 3 peptides show similar binding modes and interaction mechanisms by preferentially binding to the edge of the Aß17-42 pentamer to potentially block the Aß elongation pathway. This work provides structural-based binding information on further modification and optimization of these peptide inhibitors to experimentally enhance their inhibitory abilities against Aß aggregation.

Metformin inhibits proliferation and promotes apoptosis of HER2 positive breast cancer cells by downregulating HSP90.

PURPOSE: To investigate the effects and the possible molecular mechanisms of metformin on HER2 positive breast cancer cells. METHODS: SK-BR-3 HER2 positive breast cancer cells were treated with different concentrations of metformin. The growth inhibitory rate of the cells was calculated by MTT assay, apoptosis was detected by flow cytometry, and the expression level of heat shock protein 90 (HSP90) was performed by Western blot analysis. A control group consisted of cells treated with PBS. RESULTS: With increased concentrations of metformin, cell growth inhibitory rates increased. The growth inhibitory rates with 0.5 mM, 2mM or 8mM metformin were significantly higher compared with the control group (p<0.05). Apoptosis in the metformin treated cells was also significantly higher compared with the control group (p=0.003). The expression level of HSP90 in the metformin group was significantly lower than that in the control group. CONCLUSION: Metformin can inhibit the proliferation and promote apoptosis of HER2 positive breast cancer cells,which is maybe related to inhibition of HSP90.

Role of STAT3 Expression in Thyroid Cancer: A Meta-Analysis and Systematic Review Based on the Chinese Population.

Background: Signal transduction and activator of transcription 3 (STAT3) is an oncogene with transcriptional activity. In recent years, there have been several studies concerning the clinicopathological significance of the expression of the STAT3 protein in thyroid cancer. However, the results are still inconsistent. In this study, we conducted a meta-analysis to evaluate the relationship between the expression of STAT3 protein and thyroid cancer susceptibility and its clinicopathological characteristics. Methods: We searched the China National Knowledge Infrastructure (CNKI) database, Chinese Biomedical Literature Database (CBM), Chinese Scientific and Journal Database (VIP), Wanfang, PubMed, and EMBASE. The time frame of the publication search was from the establishment of each of the databases until December 2021. We performed a meta-analysis to quantitatively evaluate the relationship between the expression of the STAT3 protein in thyroid cancer and its clinicopathological characteristics. Results: A total of eight articles were included in the meta-analysis, covering 448 thyroid cancer patients and 227 controls. Results indicated that the expression of STAT3 protein in thyroid cancer tissue is highly expressed (OR = 14.41, 95% CI (6.94, 29.91), p < 0.001). Besides, we also discovered that STAT3 protein is negatively correlated with thyroid cancer tumor diameter and TNM stage (OR = 0.13, 95% CI (0.05, 0.33), p < 0.001; OR = 0.40, 95% CI (0.24, 0.67), p < 0.001) and positively correlated with lymph node metastasis (OR = 2.83, 95% CI (1.08, 7.46), p = 0.035). However, STAT3 expression is not related to gender (OR = 0.88, 95% CI (0.54, 1.44), p = 0.609), age (OR = 0.54, 95% CI (0.21, 1.36), p = 0.191), capsular invasion (OR = 2.98, 95% CI (0.23, 38.29), p = 0.403), or tumor multiplicity (OR = 0.25, 95% CI (0.003, 19.28), p = 0.533). Conclusions: This study reveals that STAT3 protein expression is significantly related to the susceptibility and clinicopathological characteristics of thyroid cancer. It also suggests that STAT3 may be a potential predictor of the clinical progression of thyroid cancer.

Spontaneous ventilation anesthesia combined with uniportal and tubeless thoracoscopic sympathectomy in selected patients with primary palmar hyperhidrosis.

BACKGROUND: To assess the feasibility and safety of tubeless video-assisted thoracoscopic sympathectomy (VATS) with a single 5 mm port under nonintubated, intravenous anesthesia with spontaneous ventilation in selected patients with primary palmar hyperhidrosis (PPH). METHODS: Adults (aged between 18 and 60 years) with moderate or severe PPH symptoms were enrolled. Demographic information and clinical data were obtained from 172 consecutive patients undergoing thoracoscopic surgery for PPH from March 2014 to December 2020. The primary outcomes were the rate of complications, including death, and the intraoperative conversion rate to 3-port VATS. The secondary outcomes were the conversion rate to intubated anesthesia during the operation and the surgical duration and pain score of postoperative day 0. RESULTS: In total, 172 patients were included with 88 males and 84 females. The median age was was 25 years (IQR:21-30 years). No mortalities or major morbidities occurred in any patient. The overall median surgical duration was 53 min (IQR:37-72 min). The median length of postoperative hospital stay was one day (IQR:one-one day). The median pain score of POD0 was 2 (IQR:2-2). Intraoperative conversion to 3-port VATS followed by drainage tube insertion occurred in one (0.6%) patient due to extensive pleural adhesions. No patients required conversion to intubated anesthesia during surgery. No postoperative mechanical ventilation was noted in any patient. CONCLUSIONS: For selected patients with PPH, tubeless VATS with a single 5 mm port using spontaneous ventilation anesthesia can be considered a feasible and safe operation. The surgical wound is extremely small and the operation time is shorter than the conventional technique. Trial registration This study was in conformity with the Declaration of Helsinki, and was approved by the National Ethics Committee of the University of the Hong Kong-Shenzhen Hospital (Approval number: [2020]70). We registered the study in the Chinese Clinical Trial Registry (Registration number: ChiCTR2100049063) in 2021.Informed consent was collected from all the participants of this study. URL for this clinical trial registration is: https://www.chictr.org.cn/index.aspx .

Spontaneous fermentation tunes the physicochemical properties of sweet potato starch by modifying the structure of starch molecules.

The effects of spontaneous fermentation on the molecular and physicochemical characteristics of sweet potato starch stored in tank during twelve months were investigated. From starch slurry collected during spontaneous fermentation, eight isolates showed amylolytic activity, which included two Acetobacter strains, five Bacillus strains and one Gluconacetobacter strain. By spontaneous fermentation, the amylose content and the average molecular weight of starch were significantly decreased. Besides, the native and fermented starches showed different amylopectin chain-length distribution patterns. Among them, no significant differences in granular morphology, granule size distribution, and crystalline structure. However, the thermal and pasting properties as well as the hardness of the starch gel differed significantly. Pearson's correlation analysis showed that the physicochemical properties was mainly influenced by the changes in the amylose content, amylopectin chain-length distribution as well as the average molecular weight of starch. These findings demonstrated the feasibility of spontaneous fermentation as a tool for modifying starches.

Combined caveolin-1 and epidermal growth factor receptor expression as a prognostic marker for breast cancer.

Previous studies have indicated that caveolin-1 (Cav-1) is able to bind the signal transduction factor epidermal growth factor receptor (EGFR) to regulate its tyrosine kinase activity. The aim of the present study was to evaluate the clinical significance of Cav-1 gene expression in association with the expression of EGFR in patients with breast cancer. Primary breast cancer samples from 306 patients were analyzed for Cav-1 and EGFR expression using immunohistochemistry, and clinical significance was assessed using multivariate Cox regression analysis, Kaplan-Meier estimator curves and the log-rank test. Stromal Cav-1 was downregulated in 38.56% (118/306) of tumor tissues, whereas cytoplasmic EGFR and Cav-1 were overexpressed in 53.92% (165/306) and 44.12% (135/306) of breast cancer tissues, respectively. EGFR expression was positively associated with cytoplasmic Cav-1 and not associated with stromal Cav-1 expression in breast cancer samples; however, low expression of stromal Cav-1 was negatively associated with cytoplasmic Cav-1 expression in total tumor tissues, and analogous results were identified in the chemotherapy group. Multivariate Cox's proportional hazards model analysis revealed that, for patients in the estrogen receptor (ER)(+) group, the expression of stromal Cav-1 alone was a significant prognostic marker of breast cancer. However, in the chemotherapy, human epidermal growth factor receptor 2 (HER-2)(-), HER-2(+) and ER(-) groups, the use of combined markers was more effective prognostic marker. Stromal Cav-1 has a tumor suppressor function, and the combined marker stromal Cav-1/EGFR expression was identified as an improved prognostic marker in the diagnosis of breast cancer. Parenchymal expression of Cav-1 is able to promote EGFR signaling in breast cancer, potentially being required for EGFR-mediated initiation of mitosis.

Comprehensive comparison of twenty structural characterization scales applied as QSAM of antimicrobial dodecapeptides derived from Bac2A against P. aeruginosa.

Informative numerical characterizations of amino acid residues are essential for quantitative sequence-activity modeling (QSAM). To date, a variety of structural characterization methods based on local amino acids have been proposed. However, limited detailed reports are available using same datasets and modeling methods to compare the ability to characterize structures of amino acids. Here, we evaluate the characterization capability of 20 descriptor sets on a set of antimicrobial peptides (AMPs) derived from Bac2A against P. aeruginosa. Results display the models by FASGAI, z-scales, VHSE, DPPS, HESH and ProtFP descriptors present qualified predictive capability. Moreover, the structural characterization of the studied AMPs should involve the hydrophobic, bulky and electronic properties of amino acids; besides, the secondary structural information should not be ignored. In parallel, the FASGAI-based model exhibits a more robust prediction than other models, and reasonably describe the structure-activity relationship of the studied dodecapeptides, which is in line with the reported experimental observations. This work provides references for methods of structural characterization as applied in QSAM of AMPs against P. aeruginosa.

[Spatial Heterogeneity of Soil Respiration in a Larch Plantation of North China at Different Sampling Scales].

Based on observations of soil respiration rate (Rs) and both biotic and abiotic factors in Pangquangou Nature Reserve at three sampling scales (4, 2, and 1 m), we studied the spatial heterogeneity of Rs and the factors, and analyzed impacts of soil temperature at the 5, 10 and 15 cm depth (T5, T10, T15), soil moisture over the depth of 0-10 cm (Ws), and soil total nitrogen (N), soil total organic carbon (C), ratio of carbon and nitrogen (C/N), soil total sulfur (S), litter fall mass (Lw) and litter fall moisture (Lm) on the spatial heterogeneity of Rs, respectively. We also calculated the minimum sampling number of all the factors at different confidence levels and under the responding estimation accuracy. The results showed that: (1) the spatial heterogeneity of C/N at 4 m sampling scale, Ws at 2 m sampling scale and T10, T15 at 1 m sampling scale had low variability, while the spatial variation of Rs and other related factors had medium variability. Coefficients of variation of Rs, C/N and S decreased with the increase of the sampling scales, but those of N, C, Ws, T5, T10, T15, Lw and Lm showed contrary trend; (2) the spatial autocorrelation of Rs, Ws, T5, T10, T15, Lw and Lm decreased with the decrease of sampling scales but the spatial autocorrelation of C, N, C/N increased with the decrease of sampling scales, and the spatial autocorrelation of S decreased with the decrease of the sampling scales at initial stage and then increased; (3) the key factors that influenced the spatial heterogeneity of soil respiration were different at different sampling scales. Soil temperature was the key factor influencing the spatial heterogeneity of Rs at a larger scale. However, at a smaller scale, the spatial heterogeneity of Rs was influenced by C, Lw and Lm; (4) the minimum sampling number for soil respiration measurement and its influencing factors reduced greatly with the decrease of confidence level and responding estimation accuracy. The sampling numbers of Rs, C/N and S increased with the decrease of sampling scales, while those of N, C, Ws, T5, T10, T15, Lw and Lm decreased.

RBMS3 is a tumor suppressor gene that acts as a favorable prognostic marker in lung squamous cell carcinoma.

Recent research indicates that RBMS3 may act as a tumor suppressor gene (TSG) in nasopharyngeal carcinoma (NPC) and esophageal squamous cell carcinoma (ESCC). It has been reported that RBMS3 directly binds to the promoter region of c-Myc in ESCC and that ß-catenin from both whole cell extracts and nuclear fractionation was significantly downregulated in RBMS3-transfected NPC cells compared to control cells. The aim of this study was to evaluate the clinical significance of the RBMS3 gene expression in relation to the expression of Wnt pathway components in patients with lung squamous cell carcinoma (LSCC). RBMS3, c-Myc and cytoplasmic ß-catenin were detected in 39.76, 56.63 and 89.16 % of 83 LSCC samples by immunohistochemistry, respectively, in 83 primary LSCC samples. Semiquantitative reverse transcriptase-polymerase chain reaction and Western blotting demonstrated decreased RBMS3 mRNA and expression in 33.33 % (10/30) and 36.67 % (11/30) tumor tissues, respectively. Statistical correlation analysis showed RBMS3 to be negatively correlated with c-Myc (r = -0.384, p < 0.001) and not correlated with cytoplasmic ß-catenin in the LSCC samples. Multivariate Cox proportional hazards model analysis showed that the combined marker RBMS3/c-Myc was an independent prognostic indicator of overall survival (p = 0.001; HR 3.470; IC 95 %, 1.652-7.290), and c-Myc was a prognostic indicator of disease-free survival (p < 0.001; HR 3.182; IC 95 %, 1.961-8.920). RBMS3 is a novel TSG in LSCC, and its downregulation facilitates development and progression of LSCC. Therefore, it is suggested that Rbms3 as a tumor marker may play an important role in diagnosis of LSCC.