Effects of albiflorin on oxidative stress and inflammatory responses in rats with acute spinal cord injury.

INTRODUCTION: Oxidative stress and inflammatory responses are often the predominant detrimental factors associated with spinal cord injury (SCI). This study investigates the potential therapeutic effects of albiflorin (AF) on alleviating inflammation and oxidative stress in the rat model with SCI. METHODS: Initially, the behavior of SCI-induced rats is examined by Basso-Beattie-Bresnahan score and the inclined plane examination. Then, the immunohistochemical staining of inflammasome-related protein (for instance, NACHT, LRR, and PYD domains-containing protein 3, NLRP3) is performed in combination with enzyme-linked immunosorbent assay (ELISA) of corresponding proinflammatory factors to assess the immunomodulatory effects of AF. Further, the markers involved in oxidative stress are examined by ELISA and western blot analysis analyses. RESULTS: These findings indicated that AF could alleviate motor dysfunction and the loss of neuron cells in SCI-induced rats. Mechanistically, AF could attenuate the inflammatory responses by reducing oxidative stress and activating nuclear erythroid-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) pathway in SCI rats. Depleting the antioxidant capacity by inhibiting glutathione biosynthesis could counteract the anti-inflammatory activity of AF in SCI rats. CONCLUSIONS: Together, our data suggested that AF could serve as a potential therapeutic agent against the aggravation of SCI in rats.

Study on comprehensive evaluation of environmental pollution treatment effect in coal mine subsidence area: taking Xinglongzhuang mining area of Yanzhou energy as an example.

In order to explore the effective evaluation method of environmental pollution treatment effect in China's coal mine subsidence areas, based on the literature review and analysis of current situation, combined with the reality of environmental pollution treatment (EPT) in China's coal mine subsidence areas, this paper selected four categories, including a total of 21 evaluation indicators, and drew lessons from the latest research results in relevant fields to construct the spatial niche suitability model of comprehensive evaluation of environmental pollution treatment effect in coal mine subsidence area. Taking the collapse area of Xinglongzhuang coal mine of Yanzhou energy as an example, the comprehensive evaluation and application of environmental pollution treatment effect in coal mine subsidence area were studied. It is found that the environmental pollution treatment effect of the mining area has increased from moderate pollution (level III) in 2012 to mild pollution (level I) in 2020 within 9 years. The environmental pollution treatment effect has a rapid improvement relatively, but its growth rate has decreased year by year since 2016, and the environmental pollution indicator is still at a high level. Therefore, environmental pollution treatment in the subsidence area is still a long-term task of Dongtan coal mine. The research results of this paper provide an effective quantitative analysis method for the evaluation of environmental pollution treatment effect in coal mine subsidence area, which is conducive to the continuous improvement of environmental pollution treatment effect in mining area.

DR1-CSE/H2S pathway upregulates autophagy and inhibits H9C2 cells damage induced by high glucose.

In the cardiovascular system, long-term high glucose (HG) can lead to cardiomyocyte damage. Hydrogen sulfide (H2S) reduces cell autophagy in cardiomyocytes. Dopamine 1 receptors (DR1), a specific binding receptor for dopamine, which has a significant regulatory effect on cardiomyocytes. However, it is unclear whether DR1 inhibits HG-induced cardiomyocyte damage by regulating endogenous H2S production and the level of cell autophagy. The present data indicated that the expression of DR1 and cystathionine-γ-lyase (CSE, a key enzyme for endogenous H2S production) and H2S content were significantly reduced in HG-induced cardiomyocytes, which was reversed by SKF38393 (an agonist of DR1). NaHS (an exogenous H2S donor) only increased H2S content and the expression of CSE with no effect on DR1 expression. HG reduced cell viability, the expression of Bcl-2 and Beclin1, the production of autophagosomes and LC3 II/I ratio and increased the cell apoptotic ratio, the expression of cleaved caspase-3, cleaved caspase-9, cytochrome c, P62, and p-mTOR/t-mTOR ratio. SKF38393 and NaHS reversed the effects of HG. PPG (an inhibitor of CSE) and 3MA (an inhibitor of autophagy) abolished the beneficial effect of SKF38393. In addition, AICAR (an agonist of AMPK) and Rapamycin (an inhibitor of mTOR) increased the production of autophagosomes but decreased the p-mTOR/t-mTOR ratio, which was similar to the effects of SKF38393 and 3MA. Our findings suggest that DR1 reduces the HG-induced cardiomyocyte damage via up-regulating the CSE/H2S pathway, which increases cell autophagy by inhibiting the activation of mTOR.

Exogenous hydrogen sulfide inhibits the senescence of cardiomyocytes through modulating mitophagy in rats.

Hydrogen sulfide (H2S), a gaseous molecule, has been shown to be involved in the regulation of body pathophysiological processes. Aging is related to structural and functional alterations within the heart. There is evidence that diminished mitophagy accelerates the aging process. Studies in recent years have revealed that plasma levels of H2S in humans and old rats decrease with age, and H2S acts as a cytoprotective mediator in the aging process. However, it is unclear whether H2S can delay the senescence of cardiomyocytes by regulating mitophagy. Our present results showed that exogenous H2S inhibited mitochondrial damage, oxidative stress and cell apoptosis, and enhanced mitophagy through upregulating the SIRT1-PINK1-parkin pathway in myocardial tissues of aged rats and cultured aged cardiomyocytes. Furthermore, the effect of exogenous H2S on the above indicators was the same as that of SRT1720 (a SIRT1 agonist) and kinetin (a PINK1 activator). Our findings suggest that exogenous H2S inhibits the senescence of cardiomyocytes by increasing mitophagy via upregulation of the SIRT1-PINK1-parkin pathway in rats.

5-Methylindole kills various bacterial pathogens and potentiates aminoglycoside against methicillin-resistant Staphylococcus aureus.

Antibiotic resistance of bacterial pathogens has become a severe threat to human health. To counteract antibiotic resistance, it is of significance to discover new antibiotics and also improve the efficacy of existing antibiotics. Here we show that 5-methylindole, a derivative of the interspecies signaling molecule indole, is able to directly kill various Gram-positive pathogens (e.g., Staphylococcus aureus and Enterococcus faecalis) and also Gram-negative ones (e.g., Escherichia coli and Pseudomonas aeruginosa), with 2-methylindole being less potent. Particularly, 5-methylindole can kill methicillin-resistant S. aureus, multidrug-resistant Klebsiella pneumoniae, Mycobacterium tuberculosis, and antibiotic-tolerant S. aureus persisters. Furthermore, 5-methylindole significantly potentiates aminoglycoside antibiotics, but not fluoroquinolones, killing of S. aureus. In addition, 5-iodoindole also potentiates aminoglycosides. Our findings open a new avenue to develop indole derivatives like 5-methylindole as antibacterial agents or adjuvants of aminoglycoside.

DR1 Activation Inhibits the Proliferation of Vascular Smooth Muscle Cells through Increasing Endogenous H2S in Diabetes.

Tissue ischemia and hypoxia caused by the abnormal proliferation of smooth muscle cells (SMCs) in the diabetic state is an important pathological basis for diabetic microangiopathy. Studies in recent years have shown that the chronic complications of diabetes are related to the decrease of endogenous hydrogen sulfide (H2S) in diabetic patients, and it has been proven that H2S can inhibit the proliferation of vascular SMCs (VSMCs). Our study showed that the endogenous H2S content and the expression of cystathionine gamma-lyase (CSE), which is the key enzyme of H2S production, were decreased in arterial SMCs of diabetic mice. The expression of PCNA and Cyclin D1 was increased, and the expression of p21 was decreased in the diabetic state. After administration of dopamine 1-like receptors (DR1) agonist SKF38393 and exogenous H2S donor NaHS, the expression of CSE was increased and the change in proliferation-related proteins caused by diabetes was reversed. It was further verified by cell experiments that SKF38393 activated calmodulin (CaM) by increasing the intracellular calcium ([Ca2+]i) concentration, which activated the CSE/H2S pathway, enhancing the H2S content in vivo. We also found that SKF38393 and NaHS inhibited insulin-like growth factor-1 (IGF-1)/IGF-1R and heparin-binding EGF-like growth factor (HB-EGF)/EGFR, as well as their downstream PI3K/Akt, JAK2/STAT3 and ERK1/2 pathways. Taken together, our results suggest that DR1 activation up-regulates the CSE/H2S system by increasing Ca2+-CaM binding, which inhibits the IGF-1/IGF-1R and HB-EGF/EGFR pathways, thereby decreasing their downstream PI3K/Akt, JAK2/STAT3 and ERK1/2 pathways to achieve the effect of inhibiting HG-induced VSMCs proliferation.

Dopamine 1 receptors inhibit apoptosis via activating CSE/H2 S pathway in high glucose-induced vascular endothelial cells.

High glucose (HG)-induced dysfunction of vascular endothelial cells plays a crucial role in the development of diabetic vascular complications. Inhibition of cystathionine γ-synthase/hydrogen sulfide (CSE/H2 S) pathway is one of the causes of vascular endothelial cell injury induced by HG. Dopamine D1 receptors (DR1) are widely expressed and regulate important physiological functions in the vascular system. However, the effect of DR1 inhibition on HG-induced vascular endothelial apoptosis by regulating the CSE/H2 S pathway is unclear. Therefore, we aimed to determine if DR1 can regulate the CSE/H2 S pathway and regulate the effect of DR1 on HG-induced apoptosis in human umbilical vein endothelial cells. In this study, we found that HG treatment significantly decreased the expression of DR1 and CSE and the endogenous content of H2 S; DR1 agonist SKF 38393 reversed these effects, while sodium hydrosulfide (NaHS) only increased CSE expression and the endogenous H2 S production and had no effect on DR1 expression. Meanwhile, HG significantly increased the intracellular calcium concentration ([Ca2+ ]i ), and SKF 38393 further increased HG-induced [Ca2+ ]i . In addition, HG increased the lactate dehydrogenase activity, malondialdehyde and reactive oxygen species contents, apoptotic rate, the expression of cleaved caspase-3, caspase-9, and cytochrome c, and the activity of phosphorylated-inhibitor of nuclear factor-kappaBα (NF-κBα) (p-IκBα) and phosphorylated-NF-κB (p-NF-κB), and reduced cell viability, superoxide dismutase activity, and Bcl-2 expressions. SKF 38393 and NaHS markedly reversed the effect of HG. The effect of SKF 38393 was similar to N-acetyl- l-cysteine (an inhibitor of oxidative stress) or pyrrolidinedithiocarbamate ammonium (an NF-kB inhibitor). Taken together, DR1 upregulates the CSE/H2 S pathway by increasing the [Ca2+ ]i , which inhibits HG-induced apoptosis via downregulating NF-κB/IκBα pathway in vascular endothelial cells.

n-Butanol Potentiates Subinhibitory Aminoglycosides against Bacterial Persisters and Multidrug-Resistant MRSA by Rapidly Enhancing Antibiotic Uptake.

Potentiation of traditional antibiotics is of significance for combating antibiotic-resistant bacteria that have become a severe threat to human and animal health. Here, we report that 1 min co-treatment with n-butanol greatly and specifically enhances the bactericidal action of aminoglycosides by 5 orders of magnitude against stationary-phase Staphylococcus aureus cells, with n-propanol and isobutanol showing less potency. This combined treatment also rapidly kills various S. aureus persisters, methicillin-resistant S. aureus (MRSA) cells, and numerous Gram-positive and -negative pathogens including some clinically isolated multidrug-resistant pathogens (e.g., S. aureus, Staphylococcus epidermidis, and Enterococcus faecalis) in vitro, as well as S. aureus in mice. Mechanistically, the potentiation results from the actions of aminoglycosides on their conventional target ribosome rather than the antiseptic effect of n-butanol and is achieved by rapidly enhancing the bacterial uptake of aminoglycosides, while salts and inhibitors of proton motive force (e.g., CCCP) can diminish this uptake. Importantly, such n-butanol-enhanced antibiotic uptake even enables subinhibitory concentrations of aminoglycosides to rapidly kill both MRSA and conventional S. aureus cells. Given n-butanol is a non-metabolite in the pathogens we tested, our work may open avenues to develop a metabolite-independent strategy for aminoglycoside potentiation to rapidly eliminate antibiotic-resistant/tolerant pathogens, as well as for reducing the toxicity associated with aminoglycoside use.

SKF38393 prevents high glucose (HG)-induced endothelial dysfunction by inhibiting the effects of HG on cystathionine γ-lyase/hydrogen sulfide activity and via a RhoA/ROCK1 pathway.

BACKGROUND: Endothelial dysfunction plays a crucial role in diabetic vascular complications. A decrease in hydrogen sulfide (H2S) levels is increasingly becoming a vital factor contributing to high glucose (HG)-induced endothelial dysfunction. Dopamine D1-like receptors (DR1) activation has important physiological functions in the cardiovascular system. H2S decreases the dysfunction of vascular endothelial cells. However, no studies have reported whether DR1 protects the function of vascular endothelial cells by regulating H2S levels. AIM: The present study aimed to determine whether DR1 regulates the levels of endogenous H2S, which exerts protective effects against HG-induced injury of human umbilical vein endothelial cells (HUVECs) via Ras homolog gene family member A (RhoA)/Rho-associated coiled-coil containing kinase 1 (ROCK1) signalling. METHODS: HUVECs were exposed to HG (30 mM) or normal glucose (5.5 mM) after different treatments. Cell viability, proliferation and migration were measured by Cell Counting Kit-8, EdU cell proliferation assay, transwell assay and wound healing assay, respectively. H2S probe (7-Azido-4-Methylcoumarin) was used to detect levels of H2S. The intracellular calcium concentration ([Ca2+]i) were measured using Fluo-4 AM. The protein expressions were quantified by Western blot. RESULTS: We found that HG decreased the expression of DR1 and cystathionine γ-lyase (CSE) and H2S production. The DR1 agonist SKF38393 significantly increased DR1 and CSE expression and H2S production, whereas NaHS (a H2S donor) only increased CSE expression and H2S production but had no effect on DR1 expression. Meanwhile, SKF38393 further increased the [Ca2+]i induced by HG. In addition, HG reduced cell viability and the expression of Cyclin D1 and proliferating cell nuclear antigen and increased the expression of p21C⁢i⁢p/W⁢A⁢F-1, collagen I, collagen III, matrix metalloproteinase 9, osteopontin and α-smooth muscle actin and the activity of phosphorylated RhoA and ROCK1. SKF38393 and NaHS reversed these effects of HG. PPG (a CSE inhibitor) abolished the beneficial effect of SKF38393. These effects of SKF38393 were similar to those of Y-27632 (a ROCK inhibitor). CONCLUSION: Taken together, our results suggest that DR1 activation upregulates the CSE/H2S pathway by increasing the [Ca2+]i, which protects endothelial cells from HG-induced injury by inhibiting the RhoA/ROCK1 pathway.

The DR1­CSE/H2S system inhibits renal fibrosis by downregulating the ERK1/2 signaling pathway in diabetic mice.

Glomerular mesangial cell (MC) proliferation and extracellular matrix deposition are the main pathological changes in diabetic nephropathy. Hydrogen sulfide (H2S) inhibits the proliferation of MCs. Dopamine 1 receptors (DR1) are expressed in MCs and serve important physiological roles. However, it is unclear whether DR1 activation inhibits MC proliferation by increasing endogenous H2S. The present study found that the production of H2S and the expression of DR1 and cystathionine­Î³­lyase (CSE) were decreased in the renal tissues of diabetic mice and high glucose (HG)­induced MCs. SKF38393 (a DR1 agonist) increased the production of H2S and the expression of DR1 and CSE and NaHS (an exogenous H2S donor) only increased H2S production and CSE expression but not DR1 expression. HG increased the thickness of the glomerular basement membrane, cell viability and proliferation, the expression of cyclin D1, PCNA, collagen 1 and α­smooth muscle actin and the activity of phosphorylated ERK1/2 and decreased the expression of P21 and MMP9. SKF38393 and NaHS reversed the effects of HG. PPG (a CSE inhibitor) abolished the beneficial effects of SKF38393. The beneficial effects of SKF38393 were similar to those of PD98059 (an ERK1/2 inhibitor). Taken together, the findings suggested that the DR1­CSE/H2S pathway activation attenuated diabetic MC proliferation and extracellular matrix deposition by downregulating the ERK1/2 signaling pathway.

DR1 activation promotes vascular smooth muscle cell apoptosis via up-regulation of CSE/H2 S pathway in diabetic mice.

The important role of hydrogen sulfide (H2 S) as a novel gasotransmitter in inhibiting proliferation and promoting apoptosis of vascular smooth muscle cells (VSMCs) has been widely recognized. The dopamine D1 receptor (DR1), a G protein coupled receptor, inhibits atherosclerosis by suppressing VSMC proliferation. However, whether DR1 contributes to VSMC apoptosis via the induction of endogenous H2 S in diabetic mice is unclear. Here, we found that hyperglycemia decreased the expressions of DR1 and cystathionine-γ-lyase (CSE, a key enzyme for endogenous H2 S production) and reduced endogenous H2 S generation in mouse arteries and cultured VSMCs. DR1 agonist SKF38393 increased DR1 and CSE expressions and stimulated endogenous H2 S generation. Sodium hydrosulfide (NaHS, a H2 S donor) increased CSE expressions and H2 S generation but had no effect on DR1 expression. In addition, high glucose (HG) increased VSMC apoptosis, up-regulated IGF-1-IGF-1R and HB-EGF-EGFR, and stimulated ERK1/2 and PI3K-Akt pathways. Overexpression of DR1, the addition of SKF38393 or supply of NaHS further promoted VSMC apoptosis and down-regulated the above pathways. Knock out of CSE or the addition of the CSE inhibitor poly propylene glycol diminished the effect of SKF38393. Moreover, calmodulin (CaM) interacted with CSE in VSMCs; HG increased intracellular Ca2+ concentration and induced CaM expression, further strengthened the interaction of CaM with CSE in VSMCs, which were further enhanced by SKF38393. CaM inhibitor W-7, inositol 1,4,5-trisphosphate (IP3 ) inhibitor 2-APB, or ryanodine receptor inhibitor tetracaine abolished the stimulatory effect of SKF38393 on CaM expression and intracellular Ca2+ concentration. Taken together, these results suggest that DR1 up-regulates CSE/H2 S signaling by inducing the Ca2+ -CaM pathway followed by down-regulations of IGF-1-IGF-1R and HB-EGF-EGFR and their downstream ERK1/2 and PI3K-Akt, finally promoting the apoptosis of VSMCs in diabetic mice.

[Treatment of senile lumbar spinal stenosis by unilateral approach and bilateral decompression with large channel endoscopy].

OBJECTIVE: To evaluate clinical effect of unilateral approach and bilateral decompression via large channel endoscopic system for the treatment of lumbar spinal stenosis. METHODS: The clinical data of 32 patients with lumbar spinal tenosis treated by unilateral approach and bilateral decompression via large channel endoscopy from February 2018 to February 2019 were retrospectively analyzed. There were 18 males and 14 females, aged 65 to 84 years old with an average of (70.6± 8.4) years. The course of disease was from 1 to 12 years. All 32 cases were accompanied by numbness or pain in the lower limbs, of which 28 cases were accompanied by intermittent claudication. Narrow segments were L3, 4 of 2 cases, L4, 5 of 19 cases, L5S1 of 13 cases, including double segments of 2 cases. Preoperative imaging showed 3 cases of central canal stenosis, 21 cases of bilateral lateral recess stenosis and 8 cases of mixed stenosis. Operation time and complications were recorded. X-ray, CT and MRI were analyzed at 3 days, 3 months and 1 year after operation. Visual analogue scale(VAS), Oswestry Disability Index (ODI), single continuous walking distance(SCWD) were observed before and after operation. Modified Macnab standard were used to evaluate the clinical effect at 1 year after operation. RESULTS: All the patients were followed up for 12-24 (17.68±2.43) months and all operations were successfully completed with the operation time of 70-160(85.64±11.94) min. Spinal dural tear occurred in 1 case during the operation, and sensory disturbance in the other side of lower limb in a short period of time occurred in 2 cases, all improved after corresponding treatment. Postoperative imaging showed that the spinal canal was significantly enlarged and the nerve root was fully released. Before operation and 3 days, 3 months, 1 year after operation, VAS scores of low back pain were 4.62 ±1.41, 2.73 ±1.35, 1.21 ±1.17, 1.11 ±0.34, respectively;VAS scores of leg pain were 6.83 ± 1.71, 3.10±1.50, 1.08±0.19, 0.89±0.24, respectively. VAS scores of low back pain and leg pain each time point after operation were obvious improved (P<0.05); there was significant difference between 3 months and 3 days after operation(P<0.05), and there was no significant difference between 3 months and 1 year after operation (P>0.05). Before operation and 3 days, 3 months, 1 year after operation, ODI scores were 38.40 ±6.48, 18.42 ±2.40, 5.48 ±0.77, 3.05 ±0.28, respectively; SCWD was (47.48±5.32) m, (52.89±11.23) m, (245.43±18.94) m, (468.97±55.87) m, respectively. The differences in ODI score and SCWD postoperative time points were statistically significant compared with those before operation (P<0.05). The difference between 3 months and 3 days after operation was statistically significant (P<0.05). The difference between 1 year and 3 months after operation was statistically significant (P<0.05). According to Macnab standard to evaluate clinical effect at 1 year after operation, 15 cases got excellent results, 14 good, 3 fair. CONCLUSION: It is a safe and effective way to treat lumbar spinal stenosis with unilateral approach and bilateral decompression via large channel endoscopic system. It has the advantages of sufficient decompression, less trauma, fast recovery, high safety and low incidence of postoperative complications. It can minimize the damage to the stable structure of the lumbar spine and is an ideal minimally invasive operation for the treatment of lumbar spinal stenosis.

[Effects of exogenous H2S on hepatic fibrosis in diabetic mice and its mechanism].

OBJECTIVE: To investigate the effects of exogenous hydrogen sulfide (H2S) on the hepatic fibrosis in diabetic mice and its mechanism. METHODS: Twenty-four C57 male mice (weight 22±2 g) were randomly divided into three groups (n=8): ① Normal control group (Control): Mice were intraperitoneally injected equal amount of normal saline, the injection time was the same as that of the experimental groups; ② Diabetes model groups (HG): Streptozotocin (STZ) was injected intraperitoneally once according to body weight (150 mg/kg) to establish diabetes model; ③ NaHS treatment groups (HG + NaHS): Mice were intraperitoneally injected with NaHS (100 µmol/L·kg·d) once a day for 12 consecutive weeks. The hepatocyte injury was detected by HE staining; the hepatic fibrosis was observed through Masson staining; the protein expressions of cystathionine - ß - synthetase (CBS), collagen-I (CoL-I), collagen-III (CoL-III) and matrix metalloproteinase-9 (MMP-9) were detected by Western blot. RESULTS: Compared with the control group, the damage and fibrosis of hepatocyte were significantly aggravated, the expression of CBS proteins was decreased (P＜0.01), and the expression levels of CoL-I, CoL-III and MMP-9 proteins were increased (P＜0.01) in the diabetic model group. Compared with the diabetic model group, the damage and fibrosis of hepatocyte were significantly lightened, the expression of CBS proteins was obviously increased (P＜0.01), and the expression levels of CoL-I, CoL-III and MMP-9 proteins were markedly decreased (P＜ 0.01). CONCLUSION: H2S inhibits the hepatic fibrosis in diabetic mice, and its mechanism is related to the decrease of collagen and matrix metalloproteinase-9.

Posterior percutaneous endoscopic versus traditional surgery for cervical disc herniation: A protocol for systematic review and meta analysis.

BACKGROUND: Posterior percutaneous endoscopic cervical diskectomy (P-PECD) can be used posterior microdiscectomy for cervical disc herniation. But only some small sample sizes of clinical studies have evaluated the efficacy and safety of P-PECD. This study aim to evaluated the efficacy and safety of P-PECD compared with traditional open surgery. METHODS: We will search the following seven electronic databases from their initiation to the May 1, 2020: PubMed, Embase, Cochrane Library, Web of Science, China National Knowledge Infrastructure (CNKI), Chinese Biomedical Literature Database (CBM) and Wanfang database. All randomized controlled trials, non-randomized controlled trials and retrospective case controls that compared the efficacy and safety of P-PECD and traditional open surgery in the treatment of cervical disc herniation will be included. The pooled odds ratio with 95% credible intervals (CIs) was used for the dichotomous variables. The mean difference with 95% CIs was used for the continuous variables. All analyses were conducted by Comprehensive Meta Analysis 2.0. A 2-tailed P value < 0.05 is considered statistically significant. RESULTS: The results of systematic review and meta-analysis will be submitted to a peer-reviewed journal. CONCLUSION: Our study will provide clarity regarding for clinicians to choices best surgical approach for patients with cervical disc herniation. Any changes that need to be made during the process of this study will be explained in the final full-text publication. PROTOCOL REGISTRATION NUMBER: CRD42020164011.

[Transforaminal percutaneous endoscopic lumbar discectomy combined with anchorage technique of pedicle for the treatment of high prolapse free lumbar disc herniation].

OBJECTIVE: To investigate the clinical effects of percutaneous spinal endoscopy (percutaneous endoscopy) in the treatment of high prolapse free lumbar disc herniation. METHODS: From May 2016 to June 2018, 24 patients with highly prolapse free lumbar disc herniation were enrolled in this study, including 11 males and 13 females, ranging in age from 48 to 72 years old, with an average of (59.5±7.2) years old. There were 1 case of L2, 3, 5 cases of L3, 4, 18 cases of L4, 5. The course of disease ranged from 8 to 26 months, with an average of (16.2±6.3) months. All the patients were subjected to local infiltration anesthesia. The clinical outcomes were evaluated by visual analog scale (VAS) for leg pain, low backpain and Oswestry Disability Index (ODI) at preoperative, first day after operation and 6 month after surgery. All data were statisticed by SPSS 22.0. RESULTS: All the patients were followed up, and the duration ranged from 12 to 24 months, with a mean of (17.5±5.3) months. The average operation time was(69.8±14.2) minutes. One patient had cerebrospinal fluid leakage, which improved after supine rest. VAS scores of lower back pain were 6.36±1.27, 3.94±1.03, 1.62±0.87, 0.44±0.27, 0.37±0.29. VAS scores of leg pain were 8.28±1.74, 3.16±1.24, 2.83±1.13, 0.83±0.31, 0.46±0.31, and the differences were statistically significant (P<0.05). The ODI were (48.79±9.83)%, (36.51±11.24)%, (21.05±6.35)%, (9.83±4.62)% and (7.24±4.72)% 1 day before and 1 weeks, 3 months, 6 months and 1 year after the operation, respectively. One year after the operation, the modified Macnab evaluation system was used to evaluate the clinical efficacy of the patients, 19 patients got an excellent result, 3 good, 2 fair and 0 poor. CONCLUSION: Percutaneous endoscopic pedicle anchoring technique for the treatment of high prolapse free lumbar disc herniation can effectively improve the clinical symptoms of patients, and has the advantages of less trauma, less bleeding, rapid recovery, complete removal of the nucleus pulposus, and less pain of patients, etc., its clinical efficacy is accurate, operability is strong, it is worth promoting in the clinical use.

5-Methylindole Potentiates Aminoglycoside Against Gram-Positive Bacteria Including Staphylococcus aureus Persisters Under Hypoionic Conditions.

Antibiotic resistance/tolerance has become a severe threat to human and animal health. To combat antibiotic-resistant/tolerant bacteria, it is of significance to improve the efficacy of traditional antibiotics. Here we show that indole potentiates tobramycin to kill stationary-phase Staphylococcus aureus cells after a short, combined treatment, with its derivative 5-methylindole being the most potent compound tested and with the absence of ions as a prerequisite. Consistently, this combined treatment also kills various types of S. aureus persister cells as induced by the protonophore CCCP, nutrient shift, or starvation, as well as methicillin-resistant S. aureus (MRSA) cells. Importantly, 5-methylindole potentiates tobramycin killing of S. aureus persisters in a mouse acute skin wound model. Furthermore, 5-methylindole facilitates killing of many strains of gram-positive pathogens such as Staphylococcus epidermidis, Enterococcus faecalis, and Streptococcus pyogenes by aminoglycoside antibiotics, whereas it suppresses the action of aminoglycoside against the gram-negative pathogens Escherichia coli and Shigella flexneri. In conclusion, our work may pave the way for the development of indole derivatives as adjuvants to potentiate aminoglycosides against gram-positive pathogens.

Rapid Freezing Enables Aminoglycosides To Eradicate Bacterial Persisters via Enhancing Mechanosensitive Channel MscL-Mediated Antibiotic Uptake.

Bacterial persisters exhibit noninherited antibiotic tolerance and are linked to the recalcitrance of bacterial infections. It is very urgent but also challenging to develop antipersister strategies. Here, we report that 10-s freezing with liquid nitrogen dramatically enhances the bactericidal action of aminoglycoside antibiotics by 2 to 6 orders of magnitude against many Gram-negative pathogens, with weaker potentiation effects on Gram-positive bacteria. In particular, antibiotic-tolerant Escherichia coli and Pseudomonas aeruginosa persisters-which were prepared by treating exponential-phase cells with ampicillin, ofloxacin, the protonophore cyanide m-chlorophenyl hydrazone (CCCP), or bacteriostatic antibiotics-can be effectively killed. We demonstrated, as a proof of concept, that freezing potentiated the aminoglycosides' killing of P. aeruginosa persisters in a mouse acute skin wound model. Mechanistically, freezing dramatically increased the bacterial uptake of aminoglycosides regardless of the presence of CCCP, indicating that the effects are independent of the proton motive force (PMF). In line with these results, we found that the effects were linked to freezing-induced cell membrane damage and were attributable, at least partly, to the mechanosensitive ion channel MscL, which was able to directly mediate such freezing-enhanced aminoglycoside uptake. In view of these results, we propose that the freezing-induced aminoglycoside potentiation is achieved by freezing-induced cell membrane destabilization, which, in turn, activates the MscL channel, which is able to effectively take up aminoglycosides in a PMF-independent manner. Our work may pave the way for the development of antipersister strategies that utilize the same mechanism as freezing but do so without causing any injury to animal cells.IMPORTANCE Antibiotics have long been used to successfully kill bacterial pathogens, but antibiotic resistance/tolerance usually has led to the failure of antibiotic therapy, and it has become a severe threat to human health. How to improve the efficacy of existing antibiotics is of importance for combating antibiotic-resistant/tolerant pathogens. Here, we report that 10-s rapid freezing with liquid nitrogen dramatically enhanced the bactericidal action of aminoglycoside antibiotics by 2 to 6 orders of magnitude against many bacterial pathogens in vitro and also in a mouse skin wound model. In particular, such combined treatment was able to effectively kill persister cells of Escherichia coli and Pseudomonas aeruginosa, which are per se tolerant of conventional treatment with bactericidal antibiotics for several hours. We also demonstrated that freezing-induced aminoglycoside potentiation was apparently linked to freezing-induced cell membrane damage that may have activated the mechanosensitive ion channel MscL, which, in turn, was able to effectively uptake aminoglycoside antibiotics in a proton motive force-independent manner. Our report sheds light on the development of a new strategy against bacterial pathogens by combining existing antibiotics with a conventional physical treatment or with MscL agonists.

Hypoionic Shock Facilitates Aminoglycoside Killing of Both Nutrient Shift- and Starvation-Induced Bacterial Persister Cells by Rapidly Enhancing Aminoglycoside Uptake.

Bacterial persister cells are phenotypic variants that exhibit transient antibiotic tolerance and play a leading role in chronic infections and the development of antibiotic resistance. Determining the mechanism that underlies persister formation and developing anti-persister strategies, therefore, are clinically important goals. Here, we report that many gram-negative and gram-positive bacteria become highly tolerant to typical bactericidal antibiotics when the carbon source for their antibiotic-sensitive exponential growth phase is shifted to fumarate, suggesting a role for fumarate in persister induction. Nutrient shift-induced Escherichia coli but not Staphylococcus aureus persister cells can be killed by aminoglycosides upon hypoionic shock (i.e., the absence of ions), which is achieved by suspending the persisters in aminoglycoside-containing pure water for only 1 or 2 min. Such potentiation can be abolished by inhibitors of the electron transport chain (e.g., NaN3) or proton motive force (e.g., CCCP). Additionally, we show that hypoionic shock facilitates the eradication of starvation-induced E. coli but not S. aureus persisters by aminoglycosides, and that such potentiation can be significantly suppressed by NaN3 or CCCP. Mechanistically, hypoionic shock dramatically enhances aminoglycoside uptake by both nutrient shift- and starvation-induced E. coli persisters, whereas CCCP can diminish this uptake. Results of our study illustrate the general role of fumarate in bacterial persistence and may open new avenues for persister eradication and aminoglycoside use.

Accumulated autophagosomes and excessive apoptosis during the luteal development of pregnant rats.

Autophagy plays an important role in the regression of pseudopregnant corpus luteum, whereas the involvement of autophagy in the pregnant luteolysis still remains unknown. Therefore, the present study was designed to investigate the levels and effects of accumulated autophagosomes on excessive apoptosis during the luteal development of pregnant rats. Ovaries were obtained from the female rats at the early, middle or late phase of the pregnancy, which correspondingly had three groups; including the early (ELP), middle (MLP) and late luteal phase (LLP). The results of autophagy-associated protein LC-3 clearly showed that autophagy expressed during the pregnant CL and significantly increased at LLP, while the expression changes of apoptosis related proteins cleaved caspase-3 and Bax were similar with LC-3 expression changes, indicating autophagy may be involved in the initiation of pregnant luteolysis through the induction of cellular apoptosis at LLP of pregnant ovaries. The present study was further examined the expressions of other two autophagy-associated proteins p62 and LAMP-2, since the degradation failure of autophagosomes contributed to cellular apoptosis. The results demonstrated p62 protein was accumulated at LLP while its mRNA was maintained during the whole luteal development of pregnant rats. Interestingly, the expressions of LAMP-2 mRNA and premature protein were significantly increased at MLP and LLP, while the expression of mature LAMP-2 increased at MLP and then decreased at LLP, implying autophagosomes were accumulated at LLP. Together, to our knowledge, the present study firstly demonstrated that the insufficient of lysosomal functions contributed to the impaired degradation of autophagosomes and then activated caspase-3 dependent apoptotic pathway during the pregnant luteolysis of rat ovaries, which will provide a new insight into the important mechanism regulating the luteolysis of the pregnant ovaries in mammals.

[Epidemic condition and biological characteristics of non-O1/non-O139 Vibrio cholerae in Haizhu District of Guangzhou].

OBJECTIVE: To understand the epidemic condition, distribution and biological characteristics of non-O1/non-O139 Vibrio cholerae from 2001 to 2009 in Haizhu District, to provide a scientific basis for the prevention and control of acute diarrhea. METHODS: Referring to the detecting method written in "Cholera control handbook" in the fifth edition, 764 specimens from outside environment (including the water in the Pearl River, drinking water, water for breeding fish, aquatic products and delicatessen foods), 189 specimens of healthy population and 3398 intestinal samples of patients with diarrhea, summing up to 4351 specimens for non-O1/non-O139 Vibrio cholerae test. RESULTS: 4,351 specimens were detected of 101 strains of non O1/non O139 Vibrio cholerae, the total detection rate was 2.32%; 66 strains were identified by serotyping and grouped into 26 different serotypes, the typing rate was 65.3%. The strains VBO9, VBO38 and VBO76 were the dominant bacteria.Nine strains of the same type of non-O1/non-O139 Vibrio cholerae were found from external environments also from patients with diarrhea, suggesting that there might be a correlation between the two. CONCLUSION: Non-O1/non-O139 Vibrio cholerae have diversified serotypes, causing certain infection rate among the population in this region. These bacteria exist extensively in external environment and they are the potential hazard to the citizens.