[Research progress of pyroptosis in respiratory diseases].

Pyroptosis is a programmed death mode dependent on Caspase-1/4/5/11, which is caused by activation of inflammasome, accompanied by cell membrane rupture, pore formation and cell content release. As a new type of cell death, it is widely involved in respiratory diseases, such as pulmonary fibrosis, acute lung injury, bronchopulmonary dysplasia, chronic obstructive pulmonary disease and asthma. This article reviews the mechanism of pyroptosis and its role in different respiratory diseases, in order to provide new ideas for the treatment of respiratory diseases.

[Research progress of ferroptosis-related mechanism and diseases].

Ferroptosis is a new programmed cell death characterized by iron dependent and intracellular oxidative accumulation. Current studies have confirmed that ferroptosis is involved in the occurrence and development of neurotoxicity injury, tumors, cardiovascular diseases and other diseases. This paper reviews the mechanisms of ferroptosis and its role in related diseases based on recent studies.

[Repair effect of adipose-derived mesenchymal stem cells on lung injury in rats exposed to silica].

Objective: To observe the repairing effect of adipose mesenchymal stem cells (ADSCs) on lung injury induced by silica in rats. Methods: Primary ADSCs-GFP was obtained from rats. ADSCs-GFP was injected into tail vein of silicosis model rats. The expression of green fluorescence in lungs was observed regularly to determine the homing ability of ADSCs. Primary ADSCs of rats were obtained and randomly divided into control group, exposure group, vehicle group and ADSCs group. Silicosis rat model was established by non-exposed tracheal drip method. 24 hours after silica exposure, rats in ADSCs group were injected with ADSCs of 1×10(6)/kg body weight through tail vein, and the pathological changes of lung tissue were observed and evaluated 28 days after intervention. To explore the early intervention mechanism of ADSCs on pulmonary fibrosis in silicosis model rats, apoptosis-related proteins were detected by immunohistochemistry. Results: 28 days after exposure to silica, rats in the exposure group showed obvious pulmonary fibrosis. Compared with exposure group and vehicle group, ADSCs group showed less pulmonary inflammation, less silica nodules and less collagen deposition area. Immunohistochemical results showed that the expression of Caspase-3 and cytochrome C protein decreased and Bcl-2 protein increased after ADSCs transplantation. Conclusion: ADSCs infusion has an obvious intervention effect on postponing early silicosis fibrosis in rats exposed to silica, and its mechanism is related to the regulation of apoptotic process.

Induction of apoptosis by capsaicin in hepatocellular cancer cell line SMMC-7721 is mediated through ROS generation and activation of JNK and p38 MAPK pathways.

Capsaicin, one of the major pungent ingredients found in red peppers, has been shown to have anti-carcinogenic effect on various cancer cells through multiple mechanisms. In this study, we investigated the apoptotic effect of capsaicin on human hepatocellular cancer cell line SMMC-7721, as well as the possible mechanisms involved. Treatment of SMMC-7721 cells with capsaicin resulted in a dose-dependent inhibition of cell-viability and induction of apoptosis which was associated with the generation of ROS and persistent disruption of mitochondrial membrane potential. These effects were significantly blocked when cells were pretreated with a general antioxidant N-acetyl cysteine (NAC). We also found that capsaicin induced JNK and p38 MAPK phosphorylation. JNK and p38 MAPK inhibitor effectively blocked capsaicin-induced SMMC-7721 cell apoptosis. In addition, NAC completely blocked phosphorylation of JNK and p38 MAPK induced by capsaicin. Our results indicate that capsaicin induced in SMMC-7721 cell apoptosis through generation of intracellular ROS and activation of JNK and p38 MAPK pathways.

[Comparison of safety of total laparoscopic versus laparoscopic-assisted radical gastrectomy for distal gastric cancer in older patients].

Objective: To compare the effectiveness of total laparoscopic versus laparoscopic-assisted distal gastrectomy and investigate the safety and replicability of total laparoscopic distal gastrectomy in older patients. Methods: This was a retrospective cohort study. The inclusion criteria were as follows: (1) age ≥65 years; (2) malignant gastric tumor diagnosed pathologically preoperatively; (3) Eastern Cooperative Oncology Group performance status score 0-1; (4) Grade I-III American Society of Anesthesiologists physical status; (5) preoperative clinical tumor stage I-III; (6) total laparoscopic or laparoscopic-assisted distal gastrectomy performed; and (7) gastrointestinal tract reconstruction using uncut Roux-en-Y or Billroth-II+Braun procedure. Patients who had received neoadjuvant therapy, undergone conversion to open surgery, or had serious comorbidities or incomplete data were excluded. The clinical data of 129 patients who met the above criteria and had undergone laparoscopic surgery for gastric cancer from January 2012 to December 2021 in the Gastrointestinal Cancer Center in the Beijing Cancer Hospital were analyzed. According to the operation method, the patients were divided into total laparoscopic group and laparoscopic-assisted group. Variables studied comprised: (1) surgical procedure and postoperative recovery; (2) postoperative pathological findings; and (3) postoperative complications. Measurement data with skewed distribution are represented as mean(quartile 1, quartile 3). Comparisons between groups were evaluated using the Mann-Whitney U test. Results: After propensity score matching in a 1:1 ratio, there were 40 patients in the total laparoscopic distal gastrectomy group and 40 in the laparoscopic-assisted distal gastrectomy group. Baseline characteristics did not differ significantly between the two groups (all P>0.05).Compared with the laparoscopic-assisted group, the total laparoscopic group had shorter main incisions (4.1±1.0 cm vs. 8.5±2.8 cm, t=9.375, P<0.001), time to fluid intake [4.0 (3.0, 4.8) days vs. 5.0 (4.0, 6.0) days, Z=2.167, P=0.030], and duration of indwelling abdominal drainage catheter [6.0 (6.0, 7.0) days vs. 7.0 (6.0, 8.0) days, Z=2.323, P=0.020]. Numerical Rating Scale scores on postoperative days 1 and 2 were higher in the total laparoscopic than the laparoscopic-assisted group [2.5 (1.0, 3.0) vs. 1.5 (1.0, 2.0), Z=1.980, P=0.048; 2.0 (1.0, 3.0) vs. 1.0 (1.0, 2.0), Z=2.334, P=0.020, respectively]. However, there were no significant differences between the groups in operation time, intraoperative blood loss, white blood cell count, hemoglobin concentration, or albumin concentration on postoperative day 1, time to ambulation, mean time to bowel movement, postoperative admission to the intensive care unit, length of postoperative hospital stay, or Numerical Rating Scale scores on postoperative day 3 (all P>0.05). There were also no significant differences between the two groups in maximum tumor diameter, pathological tumor type, total number of lymph nodes dissected, or total number of positive lymph nodes (all P>0.05). The incidence of postoperative complications was 15.0% (6/40) in the total laparoscopic group and the laparoscopic-assisted group; these differences are not significant (χ2<0.001, P>0.999). Conclusions: Compared with laparoscopic-assisted radical gastrectomy for distal gastric cancer, total laparoscopic surgery has the advantages of shorter incision, shorter time to fluid intake, and shorter duration of indwelling abdominal drainage catheter in older patients (age ≥65 years). Total laparoscopic radical gastrectomy for distal gastric cancer does not increase the risk of postoperative complications and could therefore be performed more frequently.

Response of AMP-activated protein kinase and lactate metabolism of largemouth bass (Micropterus salmoides) under acute hypoxic stress.

To study adaptation of largemouth bass (Micropterus salmoides) to hypoxic stress, we investigated physiological responses and lactate metabolism of the fish under acute hypoxia. The objectives of this study were to (a) observe changes in glucose, glycogen, and lactate content; (b) detect the activity of lactate dehydrogenase (LDH) in serum, brain, heart, and liver tissues; and (c) quantify the dynamic gene expression of AMP activated protein kinase alpha (AMPKα), hypoxia-inducible factor-1 alpha (HIF-1α), monocarboxylate transporter 1 (MCT1), monocarboxylate transporter 4 (MCT4), and lactate dehydrogenase-a (LDHa) following exposure to hypoxia. The fish were subjected to two hypoxia stresses (dissolved oxygen [DO] 1.20 ±â€¯0.2 mg/L and 3.50 ±â€¯0.3 mg/L, respectively) for 24 h. Our results showed that hypoxic stress significantly increased the decomposition of liver glycogen and significantly increased the concentration of blood glucose; however, the muscle glycogen content was not significantly decreased, which indicates that liver glycogen was the main energy source under acute hypoxia. Moreover, hypoxia led to accumulation of a large amount of lactic acid in tissues, possibly due to the activity of lactic acid dehydrogenase, but this process was delayed in the heart and brain relative to the liver. Additionally, hypoxia induced the expression of AMPKα, HIF-1α, MCT1, MCT4, and LDHa, suggesting that glycometabolism had switched from aerobic to anaerobic. Our results contribute to a better understanding of the molecular mechanisms of the response to hypoxia in largemouth bass.

PCR and molecular detection for differentiating Vibrio species.

Vibriosis is an economically important disease of fish, marine invertebrates (particularly penaeid shrimps), and large marine mammals and is responsible for high mortality rates in aquaculture worldwide. Some Vibrio species are also responsible for zoonoses, whereas others are relatively nonpathogenic. Using 16S- and 23S-based PCR reactions, we obtained species-specific patterns and a 470-bp band, respectively. DNA sequences obtained on the 23S rRNA gene allowed us to identify species-specific probes for Vibrio parahaemolyticus, V. alginolyticus, V. anguillarum and for a cluster of taxonomically related species: V. carchariae/harveyi/campbelii. A phylogenetic tree based on the 23S sequences confirmed previous results obtained by Western blotting.

Oestrogen replacement therapy promotes bone healing around dental implants in osteoporotic rats.

The aim of this study was to investigate the effect of oestrogen replacement therapy on bone healing around titanium implants in osteoporotic rats. Sixty 32-week-old female SD rats were used in this study. Ovariectomies were performed in 40 rats, and other 20 rats had sham operation. Eighty-four days after surgery, osteoporotic changes in proximal tibiae were seen in four ovariectomized rats when compared with two sham-operated rats. Then pure titanium implants were placed in the bilateral proximal metaphyses of the tibiae of the remaining animals. Oestrogen replacement therapy was administrated in 18 ovariectomized rats after implantation. Nine rats from each group (ovariectomized, oestrogen-treated and sham-operated) were killed at 28 and 84 days after implantation surgery respectively, and the tibiae specimens were harvested and examined. Both at 28 and 84 days after implantation surgery, most bone histomorphometric indices in the oestrogen-treated group were significantly increased compared with those in the ovariectomized group (P < 0.05 or P < 0.01). Although the oestrogen-treated group showed lower trabecular bone volume at 28 days after implant surgery and lower mineralization rate at both the two time points than the sham-operated group, there were no significant differences in other bone histomorphometric indices between the oestrogen-treated group and the sham-operated group both at 24 and 84 days after implantation. The results of this study suggest that oestrogen replacement therapy may promote bone healing around titanium implants under osteoporotic state, and therefore it seemed to be beneficial to long-term success of dental implants in clinical postmenopausal patients.

Design methodology and performance analysis of application-oriented flexure hinges.

Flexure hinges are widely employed in miniature and ultra-precision equipments with the development of precision engineering. In this paper, Castigliano's theorem and Labotto quadrature formula are utilized to derive the compliance matrix. An exclusive longitudinal section of corner-filleted flexure hinges is proposed and the curve of the cross-section is expressed by basic design parameters (r0, d, and l) and machining error parameter (η). The influences of parameters are analyzed by the defined evaluation indexes, i.e., rotation capacity, relative flexibility, and relative rotation error, which are used to assess the quality of flexure hinges. The analysis results indicate small d and optimized values of r0, l, and η will improve flexure hinges' performances. The proposed method is verified by finite element method and experiments within a 5% margin of error.

Streptococcus agalactiae, an emerging pathogen for cultured ya-fish, Schizothorax prenanti, in China.

Streptococcus agalactiae (Group B streptococcus) has emerged as an important pathogen that affects humans and animals, including aquatic species. S. agalactiae infections are becoming an increasing problem in aquaculture and have been reported worldwide in a variety of fish species, especially those living in warm water. Recently, a very serious infectious disease of unknown aetiology broke out in ya-fish (Schizothorax prenanti) farms in Sichuan Province. A Gram-positive, chain-forming coccus was isolated from moribund cultured ya-fish. The goals of this study were to identify the bacterial strains isolated from diseased fish between 2009 and 2011 in Sichuan Province, China, to evaluate the pathogenicity of the pathogen in ya-fish, crucian carp (Carassius carassius) and the Nile tilapia (Oreochromis niloticus); and to determine the susceptibility of the pathogen strains to many currently available anti-microbial agents. The virulence tests were conducted by intraperitoneal injection of bacterial suspensions. In this study, four strains of a Gram-positive, chain-forming coccus were isolated from moribund cultured ya-fish (S. prenanti). The coccoid microorganism was identified as S. agalactiae using a commercial streptococcal grouping kit and 16S rDNA sequencing analysis. Susceptibility of the isolates to 22 antibiotics was tested using the disc diffusion method. All isolates showed a similar antibiotic susceptibility, which were sensitive to amoxicillin, ciprofloxacin, lomefloxacin, chloramphenicol, rifampin, vancomycin, azithromycin, florfenicol, cefalexin, cefradine and deoxycycline and resistant to gentamicin, sinomin (SMZ/TMP), penicillin, tenemycin, fradiomycin and streptomycin. Furthermore, the virulence tests were conducted by intraperitoneal injection of the isolated strain GY101 in ya-fish, crucian carp and the Nile tilapia. This coccus was lethal to ya-fish, Nile tilapia and crucian carp. The mortality rates of infected ya-fish were 100%, 100%, 60% and 20% at doses of 1.0 × 107, 1.0 × 106, 1.0 × 105 and 1.0 × 104 CFU/fish, respectively. The values were 100%, 80%, 60% and 30% for Nile tilapia and 100%, 60%, 10% and 0% for crucian carp. To our knowledge, this is the first report of S. agalactiae as a pathogen of ya-fish.

Urethane-induced hyperglycemia.

AIM: To study the effects of urethane, at anesthetic dose, on the blood glucose levels in normal rats and hyperglycemic rats, and its effects on the hypoglycemic action of exogenous insulin in alloxan-treated rats. METHODS: Blood glucose concentration was measured with the glucose oxidase method. RESULTS: Urethane at anesthetic dose 1.5 g.kg-1 increased the blood glucose levels in fasting (to 2.6 +/- 0.3 g.L-1, P < 0.01) or glucose-loaded (to 3.9 +/- 0.4 g.L-1, P < 0.01) rats. It did not modify the hyperglycemia induced by epinephrine (normal islet beta-cells) or alloxan (impaired islet beta-cells). In the rats treated with alloxan, blood glucose level decreased to 1.8 +/- 0.7 g.L-1 at 200 min after administration of insulin from control level of 7.0 +/- 2.3 g.L-1, but the hypoglycemic action of exogenous insulin was abolished by urethane. CONCLUSION: Hyperglycemic action of urethane was due to its inhibiting effect on the hypoglycemic effect of insulin, except for its known mechanism of increased sympathetic release.

Adhesion of lymphoid cell lines to fibronectin-coated substratum: biochemical and physiological characterization and the identification of a 140-kDa fibronectin receptor.

Little information is available on the interaction between lymphocytes and fibronectin (fn). To gain a better understanding on this issue we examined the adhesion of 12 lymphoid cell lines, each exhibiting different phenotypic characteristics, to fn-coated substratum. Of the cell lines tested, five that adhered to fn possessed B-cell characteristics, while neither the T-cell lines nor the pre-B-cell line adhered. The physiology and biochemistry of adhesion of a B-cell line, MOPC 315, were examined in detail. Our results indicated that (1) the adhesion was a specific and time-dependent process, (2) the adhesion was temperature-dependent and inhibited by metabolic inhibitors, such as KCN and 2-deoxyglucose, (3) the presence of cycloheximide and pretreatment of cells with trypsin inhibited adhesion, (4) a 140-kDa surface protein was immunoprecipitated by anti-fn receptor antibodies, (5) the presence of divalent cations was essential for adhesion, (6) the presence of colchicine had no effect on adhesion, while cytochalasin B partially inhibited adhesion, and (7) the treatment of cells by both phorbol 12-myristate 13-acetate and calcium ionophore A23187 enhanced adhesion. In this study, we have established the interaction between lymphoid cell lines and fn. Such an interaction might play an important role in the behavior of lymphocytes in tissues.