Study on an Animal Model of Seawater Immersion Injury Following Hemorrhagic Shock.

INTRODUCTION: To establish an animal model of delayed intravenous resuscitation following seawater immersion after hemorrhagic shock (HS). METHODS: Adult male SD rats were randomly divided into three groups: group NI (HS with no immersion), group SI (HS with skin immersion), and group VI (HS with visceral immersion). Controlled HS in rats was induced by withdrawing 45% of the calculated total blood volume within 30 min. In SI group, immediately after blood loss, 0.5 cm below the xiphoid process was immersed in artificial seawater, at (23 ± 1) °C, for 30 min. In VI group, the rats were performed by laparotomy and the abdominal organs were immersed in (23 ± 1) °C seawater for 30 min. Two hours after seawater immersion, the extractive blood and lactated Ringer's solution were delivered intravenously. The mean arterial pressure (MAP), lactate, and other biological parameters were investigated in different time points. The survival rate of 24 h after HS was recorded. RESULTS: After seawater immersion following HS, MAP and abdominal viscera blood flow decreased significantly, and the plasma levels of lactate and the organ function parameters were increased than the baseline. The above changes in VI group were more serious than those in SI and NI group, especially in myocardial and small intestine damage. The hypothermia, hypercoagulation, and metabolic acidosis were also observed after seawater immersion; the injury was more severely in VI group than that of SI group. However, the plasma levels of sodium, potassium, chlorine, and calcium in VI group were significantly higher than those before injury and in the other two groups. In the VI group, the level of plasma osmolality in instant, 2 h, and 5 h after immersion was 111%, 109%, and 108% of the SI group, respectively, all P < 0.01. The 24-h survival rate of VI group was 25%, which was significantly lower than that of SI group (50%) and NI group (70%), P < 0.05. CONCLUSIONS: The model fully simulated the key damage factors and field treatment conditions, reflected the effects of low temperature and hypertonic damage caused by seawater immersion on the severity and prognosis of naval combat wounds, and provided a practical and reliable animal model for the study of field treatment technology of marine combat shock.

131 I radiolabeled immune albumin nanospheres loaded with doxorubicin for in vivo combinatorial therapy.

For the purpose of providing new insights for high-efficiency radiochemotherapy of hepatoma, a radioimmunotherapy and chemotherapy combinatorial therapy albumin nanospheres 131 I-antiAFPMcAb-DOX-BSA-NPs was designed and prepared. It was obtained in a high radiolabeling yield approximately 65% with the radiochemical purity of over 98%. The transmission electron microscope showed that the nanospheres obtained in good monodispersion with a diameter of approximately 230 nm. The doxorubicin (DOX) loading capacity of the DOX-BSA-NPs nanoparticles was determined to be approximately 180 µg/mg and 95.79 ± 3.89%. DOX was released gradually in 6 days. In vivo tumor-growth inhibition experiments showed that after treating with 131 I-antiAFPMcAb-DOX-BSA-NPs for 14 days, the tumor volume decreased more obvious than that of other 2 time points and the control groups. All the results indicated that the radiolabeled immune albumin nanospheres 131 I-antiAFPMcAb-DOX-BSA-NPs could significantly inhibit the hepatoma tumor growth with the strategy of combinatorial radioimmunotherapy and chemotherapy.

Acacetin attenuates mice endotoxin-induced acute lung injury via augmentation of heme oxygenase-1 activity.

Acacetin, a natural product, has a wide spectrum of biological activities such as antioxidant properties. In the present study, we examined whether Acacetin has any beneficial role on lipopolysaccharide (LPS)-induced acute lung injury (ALI) and, if so, whether its effect is mediated via heme oxygenase-1 (HO-1), an antioxidant enzyme playing an important role in ALI. Male BALB/c mice were stimulated with LPS intratracheal instillation to induce ALI. Acacetin was administrated 2 h after LPS challenge. Samples were harvested 10 h after LPS administration. We demonstrated that LPS challenge significantly induced lung histological alterations such as inflammation and edema. Acacetin administration notably attenuated these changes and reduced tumor necrosis factor-α and interleukin-1ß in lung tissues. The LPS-induced reactive oxygen species generation was markedly suppressed by Acacetin. Furthermore, Acacetin treatment significantly elevated pulmonary HO-1 and nuclear factor erythroid-2-related factor 2 (Nrf2) activities. However, the beneficial action of Acacetin was markedly abolished when pretreated with zinc protoporphyrin, an inhibitor of HO-1. In in vitro studies, Acacetin notably increased the HO-1 expression in pulmonary microvascular endothelial cells. During knockdown of Nrf2 by siRNA, the effect of Acacetin on HO-1 expression was significantly reversed. Acacetin attenuates LPS-induced ALI in mice. This protective effect of Acacetin may be mediated, in part, through an HO-1-dependent pathway.

Comparison of titanium elastic intramedullary nailing versus injection of bone marrow in treatment of simple bone cysts in children: a retrospective study.

BACKGROUND: Simple bone cysts are common benign lytic bone lesions in children. The main goals of treatment for bone cysts are to prevent pathological fractures, support the healing process, and prevent recurrence. This retrospective study compared fixation with titanium elastic intramedullary nailing (TEN) versus aspiration and injection of autogenous bone marrow (ABM) for the treatment of simple bone cysts in children. METHODS: Forty-six patients (mean follow-up, 62 months; range, 34-71 months) who presented with bone cysts (30 in the humerus, 16 in the femur) from January 2006 to December 2012 were retrospectively evaluated. Patients were treated with either TEN or ABM injection. Radiographs were evaluated according to previously established criteria. Clinical evaluations of pain, infection, additional fractures, and range of motion were performed. RESULTS: After treatment, all patients were pain-free and had normal range of motion in adjacent joints. In the ABM group, 14 (60.9 %) bone cysts completely healed, six (26.1 %) healed with small residuals after two injections, and three (13.0 %) recurred. In the TEN group, 16 (69.6 %) bone cysts completely healed, four (17.4 %) healed with small residuals, and three (13.0 %) recurred. There were no significant differences in radiographic outcomes between groups at the final follow-up (P > 0.05). Three patients developed skin irritation as a result of the nail ends. Additional fractures occurred in four patients who underwent ABM injection and in two patients who underwent TEN. No significant associations were found between pathological fractures and cyst activity, location, or treatment outcomes in the patients studied. CONCLUSIONS: Both TEN and ABM injection are safe and effective treatment for bone cysts. ABM injection promotes osteogenic differentiation of bone marrow stromal cells; multiple injections can reduce the likelihood of recurrence. TEN stabilizes the affected bone and thus allows early limb mobilization. It also reduces pressure in the capsule wall by continuous decompression to promote cyst healing. ABM injections can be used to treat cyst recurrence after previous TEN, with favorable results.

Electroacupuncture ST36 prevents postoperative intra-abdominal adhesions formation.

BACKGROUND: We have recently proved electroacupuncture (EA) ST36 exerted an anti-inflammatory effect in the early phase of intra-abdominal adhesion formation. Evidences indicate that the anti-inflammatory effect of EA ST36 involves a cholinergic anti-inflammatory pathway-dependent mechanism via the vagus nerve. However, the exact effects and accurate vagal modulation of acupuncture in prevention of postoperative intra-abdominal adhesion formation has not been thoroughly evaluated. MATERIALS AND METHODS: Sprague-Dawley rats subjected to abdominal adhesion lesions operation at the cecum and abdominal wall were randomly divided into six groups as follows: (a) EAN: EA non-channel acupoints; (b) EA: EA ST36 after abdominal lesions; (c) VGX/EA: vagotomy (VGX) after abdominal lesions, then EA ST36; (d) VGX/EAN: VGX after abdominal lesions, then EAN; (e) α-BGT/EA: intraperitoneal injection of α-bungarotoxin (α-BGT, an antagonist of α7 subunit of cholinergic nicotinic receptor) before EA ST36, and (f) α-BGT/EAN group: α-BGT injection before EAN. Seven days after abdominal surgical lesions, the levels of tumor necrosis factor-α (TNF-α) and vascular endothelial growth factor (VEGF) in the adhesive tissue were evaluated, macroscopic observation and histopathologic evaluation of adhesion formation and assessment of angiogenesis by immunohistochemical staining of platelet endothelial cell adhesion molecule-1 (CD31) were performed. RESULTS: EA ST36 reduced TNF-α and VEGF levels in adhesive tissue homogenates 7 d after surgery, whereas vagotomy or intraperitoneal injection of α-BGT before EA ST36 reversed its suppressive effects. EA at non-channel acupoints with or without vagotomy or intraperitoneal injection of α-BGT before EA had no suppressive effects on TNF-α and VEGF levels. EA ST36 alleviated the adhesion formation, with both of macroscopic and histopathologic adhesion scores significantly lower than those of the EAN group (1.56 ± 0.29 versus 3.00 ± 0.82, 1.35 ± 0.4 versus 3.91 ± 0.8, respectively, both P < 0.05). Compared with the EAN group, EA ST36 significantly decreased angiogenesis evidenced by reduced CD31 positive microvessel density in adhesive tissue. CONCLUSIONS: EA ST36 might reduce the postoperative local inflammatory response, attenuate the angiogenesis, and alleviate the adhesion formation partly via activating the cholinergic anti-inflammatory mechanism.

Upregulating nonneuronal cholinergic activity decreases TNF release from lipopolysaccharide-stimulated RAW264.7 cells.

Nonneuronal cholinergic system plays a primary role in maintaining homeostasis. It has been proved that endogenous neuronal acetylcholine (ACh) could play an anti-inflammatory role, and exogenous cholinergic agonists could weaken macrophages inflammatory response to lipopolysaccharide (LPS) stimulation through activation of α7 subunit-containing nicotinic acetylcholine receptor (α7nAChR). We assumed that nonneuronal cholinergic system existing in macrophages could modulate inflammation through autocrine ACh and expressed α7nAChR on the cells. Therefore, we explored whether LPS continuous stimulation could upregulate the nonneuronal cholinergic activity in macrophages and whether increasing autocrine ACh could decrease TNF release from the macrophages. The results showed that, in RAW264.7 cells incubated with LPS for 20 hours, the secretion of ACh was significantly decreased at 4 h and then gradually increased, accompanied with the enhancement of α7nAChR expression level. The release of TNF was greatly increased from RAW264.7 cells at 4 h and 8 h exposure to LPS; however, it was suppressed at 20 h. Upregulating choline acetyltransferase (ChAT) expression through ChAT gene transfection could enhance ACh secretion and reduce TNF release from the infected RAW264. 7cells. The results indicated that LPS stimulation could modulate the activity of nonneuronal cholinergic system of RAW264.7 cells. Enhancing autocrine ACh production could attenuate TNF release from RAW264.7 cells.

Low osteotomy cut of Dega procedure for older children with developmental dysplasia of the hip.

The effect on acetabular management in developmental dysplasia of the hip (DDH) patients aged 7 or older with modified low Dega osteotomy procedure was evaluated. Patients between 7 and 14 years old were managed with modified low Dega osteotomy and open reduction and concomitant procedures to evaluate whether low level osteotomy improved the clinical and radiologic outcomes after treatment. Clinical status was assessed using the modified McKay's criteria; radiologic evaluations were assessed for the modified Severin classification, the mean acetabular index (AI), Sharp angle and center-edge (CE) angle. And occurrence of triradiate cartilage injury and complications was recorded. Forty-two DDH patients (57 hips) between 7 and 14 years old were managed with modified low Dega osteotomy. The results demonstrated the latest follow-up 43 hips (75.4%) were rated excellent and 10 hips (17.5%) rated good according to the modified McKay criteria and 41 hips (71.9%) were rated excellent and 11 hips (19.3%) rated good according to Modified Severin classification, respectively. The mean Hip Score improved from 69.53 ±â€…7.14 before the operation to 93.17 ±â€…8.43 at the final follow-up. The mean AI changed from 31.9° to 20.2°, mean Sharp angle decreased from 59.3° to 38.8° and mean CE angle increased from -10.9° to 35.2°, preoperatively and at latest follow-up, respectively. The modified low Dega osteotomy combined with open reduction and concomitant procedures were found to be adequate in improving instant and sustained clinical and radiographic outcomes for the late detected pediatric walking DDH patients.

Unveiling camouflaged and partially occluded colorectal polyps: Introducing CPSNet for accurate colon polyp segmentation.

BACKGROUND: Segmenting colorectal polyps presents a significant challenge due to the diverse variations in their size, shape, texture, and intricate backgrounds. Particularly demanding are the so-called "camouflaged" polyps, which are partially concealed by surrounding tissues or fluids, adding complexity to their detection. METHODS: We present CPSNet, an innovative model designed for camouflaged polyp segmentation. CPSNet incorporates three key modules: the Deep Multi-Scale-Feature Fusion Module, the Camouflaged Object Detection Module, and the Multi-Scale Feature Enhancement Module. These modules work collaboratively to improve the segmentation process, enhancing both robustness and accuracy. RESULTS: Our experiments confirm the effectiveness of CPSNet. When compared to state-of-the-art methods in colon polyp segmentation, CPSNet consistently outperforms the competition. Particularly noteworthy is its performance on the ETIS-LaribPolypDB dataset, where CPSNet achieved a remarkable 2.3% increase in the Dice coefficient compared to the Polyp-PVT model. CONCLUSION: In summary, CPSNet marks a significant advancement in the field of colorectal polyp segmentation. Its innovative approach, encompassing multi-scale feature fusion, camouflaged object detection, and feature enhancement, holds considerable promise for clinical applications.

Rapid Detection of Malaria Based on Hairpin-Mediated Amplification and Lateral Flow Detection.

Malaria is listed as one of the three most hazardous infectious diseases worldwide. Travelers and migrants passing through exit and entry ports are important sources of malaria pandemics globally. Developing accurate and rapid detection technology for malaria is important. Here, a novel hairpin-mediated amplification (HMA) technique was proposed for the detection of four Plasmodium species, including P. falciparum, P. vivax, P. malariae, and P. ovale. Based on the conserved nucleotide sequence of Plasmodium, specific primers and probes were designed for the HMA process, and the amplicon can be detected using lateral flow detection (LFD); the results can be read visually without specialized equipment. The specificity of HMA-LFD was evaluated using nucleic acids extracted from four different Plasmodium species and two virus species. The sensitivity of HMA-LFD was valued using 10× serial dilutions of plasmid containing the template sequence. Moreover, 78 blood samples were collected to compare HMA-LFD and qPCR. The HMA-LFD results were all positive for four different Plasmodium species and negative for the other two virus species. The sensitivity of HMA-LFD was tested to be near five copies/µL. The analysis of clinical samples indicated that the consistency of HMA-LFD and qPCR was approximately 96.15%. Based on these results, the HMA-LFD assay was demonstrated to be a rapid, sensitive, and specific technique for the detection of Plasmodium and has great advantages for on-site detection in low-resource areas and exit and entry ports.

Study on CAT activity of tomato leaf cells under salt stress based on microhyperspectral imaging and transfer learning algorithm.

Salt stress easily leads to oxidative stress and promotes the catalase (CAT) response in tomato leaves. For the changes in catalase activity in leaf subcells, there is a need for a visual in situ detection method and mechanism analysis. This paper, taking catalase in leaf subcells under salt stress as the starting point, describes the use of microscopic hyperspectral imaging technology to dynamically detect and study catalase activity from a microscopic perspective, and lay the theoretical foundation for exploring the detection limit of catalase activity under salt stress. In this study, a total of 298 microscopic images were obtained under different concentrations of salt stress (0 g/L, 1 g/L, 2 g/L, 3 g/L) in the spectral range of 400-1000 nm. With the increase in salt solution concentration and the advancement of the growth period, the CAT activity value increased. Regions of interest were extracted according to the reflectance of the samples, and the model was established by combining CAT activity. The characteristic wavelength was extracted by five methods (SPA, IVISSA, IRFJ, GAPLSR and CARS), and four models (PLSR, PCR, CNN and LSSVM) were established according to the characteristic wavelengths. The results show that the random sampling (RS) method was better for the selection samples of the correction set and prediction set. Raw wavelengths are optimized as the pretreatment method. The partial least-squares regression model based on the IRFJ method is the best, and the coefficient of correlation (Rp) and root mean square error of the prediction set (RMSEP) are 0.81 and 58.03 U/g, respectively. According to the ratio of microarea area to the area of the macroscopic tomato leaf slice, the Rp and RMSEP of the prediction model for the detection of microarea cells are 0.71 and 23.00 U/g, respectively. Finally, the optimal model was used for quantitative visualization analysis of CAT activity in tomato leaves, and the distribution of CAT activity was consistent with its color trend. The results show that it is feasible to detect the CAT activity in tomato leaves by microhyperspectral imaging combined with stoichiometry.

[Effects of PNU282987 on organ function and survival in dogs with lethal burn shock].

OBJECTIVE: To investigate the effects of PNU282987, a α7 nicotinic acetylcholine receptor agonist (α7nAChR), on organ function and survival rate in dogs with lethal burn shock. METHODS: Twelve adult male Beagle dogs were subjected to 50% total body surface area (TBSA) full-thickness flame injury, and then they were randomly divided into a burn group and a PNU282987 group (PNU group), each n=6. The dogs in PNU group received PNU282987 (0.38 mg/kg, venous pumping) and the dogs in burn group received equal amount of normal saline solution as the control group. The mean arterial pressure (MAP) and the plasma levels of tumor necrosis factor-α (TNF-α), alanine aminotransferase (ALT), MB isoenzyme of creatine kinase (CK-MB), creatinine (Cr), blood urea nitrogen (BUN) were continuously determined before and 0.5, 2, 4, 8, 12, 24 hours after burn. All the above measurements were performed with animals in conscious and cooperative state. At the end of 24-hours-period experiment, the survival rate was recorded. RESULTS: The MAP significantly decreased after burn compared with the baseline data before-injury. The level of MAP in PNU group were significantly higher than those of the burn group from 4 hours after burn, and it returned to 83.6% of baseline level at 24 hours. In contrast, those in the burn group progressively decreased with time till death. The plasma levels of TNF-α in PNU group were significantly lower than those of burn group at each time points post injury. The ALT, Cr, BUN and CK-MB of the burn group increased persistently, while those of the PNU group increased at first and decreased subsequently except for ALT increased persistently, and they were all significantly lower than those of the burn group till to the time point of 12 hours (ALT:51.2±7.0 U/L vs. 104.8±7.4 U/L, Cr:42.7±5.4 µmol/L vs. 88.5±4.8 µmol/L, BUN:4.9±1.2 mmol/L vs. 14.7±1.4 mmol/L, CK-MB:564.0±39.1 U/L vs. 734.0±35.9 U/L, all P<0.05). At the end of 24-hours-period experiment, the survival rate of the PNU group was 50% (3/6) and significantly higher than that of the burn group 0(0/6). CONCLUSIONS: The results indicated that PNU282987 decrease the levels of inflammatory cytokine, improve the organ functions and increase 24-hour survival rate in dogs with lethal burn injury. And PNU282987 may have potential clinical application.

Pyloric resection and delayed gastric liquid emptying in rats.

BACKGROUND: Surgical resection of the distal stomach impairs gastric emptying. Generally, pylorus and the antrum are removed in the distal gastrectomy, however, the pylorus is removed individually under specific circumstances. We focus on the relation between the pyloric resection and the gastric liquid emptying. AIMS: The present investigation aimed to explore the pylorectomy how to influence gastric liquid emptying in rats. METHODS: Pylorectomy and end-to-end gastroduodenal anastomosis were conducted in rats. Electrodes were implanted in the gastrointestinal serosal surface near the stoma. Total stomach, proximal stomach, distal stomach and duodenal liquid emptying, myoelectricities in the gastrointestinal tract near the stoma, and structures were examined with scintigraphy, electrode recording in vivo, and electron microscopy, respectively. RESULTS: Delayed total stomach and distal stomach emptying were found in pylorectomy rats (p<0.001). However, there was no difference in the proximal stomach and the duodenal liquid emptying compared to the controls (p>0.05). The myoelectricity of 3-5 cpm (cycles/min) in antrum and 10-12 cpm in duodenum were found in the controls and no retrograde or antegrade myoelectricities were recorded in the duodenum and antrum. High-frequency myoelectricities (tachygastria) were recorded in the antrum near the stoma (p<0.01), the retrograde and antegrade myoelectricities propagating through the stoma were recorded, and the regenerated interstitial cells of Cajal were found in stoma under electron microscope observation in pylorectomy rat. CONCLUSIONS: The gastroduodenal incoordination and abnormal myoelectricity related to impaired contraction in the antrum caused the delayed liquid gastric emptying in pylorectomy rats.

Edaravone attenuates smoke inhalation injury in rats by the Notch pathway.

OBJECTIVE: To explore the protective effect of inhaled edaravone (EDA) on inflammation, oxidative stress (OS), and pulmonary function (PF) in rats after smoke inhalation injury (SII), as well as its mechanisms. METHODS: Twenty-four rats were designated as group A (model group), group B (EBA prevention group), group C (low-dose group) and group D (high-dose group) (n=6 for each group). SII models were induced in all groups. After successful modeling, rats in each group were treated accordingly. After 6 hours of modeling, assessments of PF, oxygenation index (OI), inflammatory cytokine expression, oxidative stress index (OSI), wet/dry weight ratio (W/D), total lung water (TLW), and the expression of Notch markers were carried out. RESULTS: Compared with group A, the remaining groups had higher peak respiratory velocity (PEF), forced expiratory volume in the first second (FEV1), FEV1/forced vital capacity (FVC) and OI, as well as lower W/D and TLW; levels of serum superoxide dismutase (SOD), malondialdehyde (MDA), tumor necrosis factor-α (TNF-α), and interleukin (IL)-6 decreased, and those of serum myeloperoxidase (MPO) and IL-10 increased. Levels of PEF, FEV1, FVC, OI, MPO, and IL-10 were higher in group A than in groups C and D, and those of W/D, TLW, SOD, MDA, TNF-α, and IL-6 were lower. Levels of Notch markers NICD, Hes1 and Hes5 were downregulated in groups B, C, and D, and in group B were lower than those in groups C and D. CONCLUSION: Inhaled EDA is able to alleviate inflammation and OS and effectively improve PF in rats after SII, possibly by inhibiting the Notch pathway.

China county based COPD screening and cost-effectiveness analysis.

BACKGROUND: Early diagnosis and treatment of chronic obstructive pulmonary disease (COPD) can improve pulmonary function and reduce the incidence of exacerbations of acute COPD, thereby improving the patient's quality of life. In China, due to limited medical resources, COPD patients often cannot be diagnosed and treated early, so the benefits of early screening of patients with COPD high risk still lack effective supporting data. METHODS: Based on the data collected through the "Dual-lung screening initiative" performed by the Datan Health Center in Fengning Manchu Autonomous County on July 12 and July 19, 2020, the patients with COPD high risk who underwent early COPD screening were evaluated. The screened patients were mainly smokers aged over 45 and those with long-term exposure to secondhand smoke, underlying lung diseases, a family history of lung diseases, or respiratory symptoms. After filling out the COPD-population screener (COPD-PS) questionnaire, those who had a score of above 5 were subjected to the portable pulmonary function test. Subjects with a forced expiratory volume in 1 s/forced vital capacity (FEV1/FVC) ratio <0.7 were diagnosed with COPD. A cost-effectiveness analysis model was applied to assess the screening's economic efficiency. The model was constructed through a combination of a decision tree and a Markov model, which enabled the simulation of the disease progression of COPD high risk patients under the condition of being screened or not being screened, to evaluate the incremental cost-effectiveness ratio between the two conditions. RESULTS: A total of 700 questionnaires were issued for screening and 379 questionnaires were valid, and 92 patients were diagnosed with COPD (24.27%). The modeling results showed that among patients with COPD high risk, those receiving early screening had an increase in quality-adjusted life years (QALYs) by 0.28 units over those who did not, and a cost of 6,366.19 Renminbi (RMB) would be needed, which was much lower than the set willingness-to-pay threshold (70,888.99 RMB) [an equivalent of the 2019 per capita gross domestic product (GDP)]. CONCLUSIONS: For COPD high risk patients, receiving early screening has a cost-effective advantage over no screening. Therefore, early screening should be vigorously promoted to COPD high risk patients.

Purification and characterization of gelatinase-like proteinases from the dark muscle of common carp (Cyprinus carpio).

Gelatinolytic proteinases from common carp dark muscle were purified by 30-60% ammonium sulfate fractionation and a combination of chromatographic steps including ion exchange on DEAE-Sephacel, gel filtration on Sephacryl S-200, ion exchange on High-Q, and affinity on gelatin-Sepharose. The molecular masses of these proteinases as estimated by SDS-PAGE were 75, 67, and 64 kDa under nonreducing conditions. The enzymes revealed high activity at a slightly alkaline pH range, and their activities were investigated using gelatin as substrate. Metalloproteinase inhibitors, EDTA, EGTA, and 1,10-phenanthroline, almost completely suppressed the gelatinolytic activity, whereas other proteinase inhibitors did not show any inhibitory effect. Divalent metal ion Ca (2+) is essential for the gelatinolytic activity. Furthermore, these gelatinolytic proteinases hydrolyze native type I collagen effectively even at 4 degrees C, strongly suggesting their involvement in the texture softening of fish muscle during the post-mortem stage.

[Protective effects of valproic acid on gut barrier function after major burn injury and its mechanism].

OBJECTIVE: To investigate the potential protective effects of valproic acid (VPA) on gut barrier function after major burn injury in rats and its mechanism. METHODS: Forty male Sprague-Dawley (SD) rats were divided into sham + normal saline (NS), sham + VPA, scald + NS, and scald + VPA groups, with 10 rats in each group. Rat with 55% total body surface area (TBSA) third-degree severe-burns model was reproduced by immersing into 80 °C water, and the rats in sham groups were given sham-burns by immersing into 37 °C water. The rats after severe-burns were immediately treated with 0.25 mL of 300 mg/kg VPA or NS by subcutaneous injection. Rats were sacrificed at 2 hours and 6 hours after injury, and abdominal aortic blood and ileal tissue were harvested. The levels of vascular endothelial growth factor (VEGF) were determined by enzyme-linked immunosorbent assay (ELISA). The intestinal permeability was evaluated by fluorescein isothiocyanate-dextran (FITC-dextran) determination. The histomorphological changes in gut barrier were evaluated by Chiu grading system. Levels of acetylated lysine at the ninth position of histone 3 protein (Ac-H3K9), hypoxia-inducible factor 1α (HIF-1α), zona occludens 1 (ZO-1) and myosin light chain kinase (MLCK) were determined by immunofluorescence staining and Western Blot. RESULTS: Compared with sham + NS group, rats in scald + NS group showed intestinal mucosal damage 2 hours after burn injury, as well as increased mucosal permeability, protein expression levels of HIF-1α, VEGF, MLCK, and lowered levels of AC-H3K9 and ZO-1. These changes were much more prominent at 6 hours after injury. VPA treatment significantly attenuated the burn-induced intestinal damage. Compared with scald + NS group, the protective effects in scald + VPA group was not evident at 2 hours after injury; however, intestinal damage was much less severe at 6 hours after injury (Chiu score: 2.03±0.27 vs. 3.12±0.15), intestinal permeability was significantly decreased [FITC-dextran (µg/L): 709±76 vs. 1 138±75], histone acetylation was enhanced [Ac-H3K9 (gray value): 1.55±0.12 vs. 0.48±0.12], ZO-1 degradation was significantly inhibited (gray value: 0.69±0.12 vs. 0.43±0.16), the protein expression levels of VEGF and MLCK were significantly down-regulated [VEGF (ng/mg): 51.7±3.7 vs. 71.2±4.3, MLCK (gray value): 1.98±0.20 vs. 2.80±0.24], while the HIF-1α protein expression levels were significantly reduced at both 2 hours and 6 hours after injury (gray value: 2.50±0.39 vs. 3.88±0.42 at 2 hours, 1.83±0.42 vs. 4.42±0.41 at 6 hours, all P < 0.05). CONCLUSIONS: Severe burn injury can induce histone deacetylation, ZO-1 degradation and intestinal barrier dysfunction. VPA can improve the levels of histone acetylation and ZO-1, and protect intestinal epithelial barrier function. These may probably be mediated through inhibiting HIF-1α and its downstream gene VEGF and MLCK.

A novel hGHRH analog and its comparative activity.

Growth hormone releasing hormone is one of the hormones secreted from the hypothalamus. Because of its potential applications in agriculture and medicine, its short half-life and its expensive chemical synthesis, an analog with high GHRH activity and prolonged half-life was sought after. The fusion partner gene with 127 amino acid residues of the C-terminus from L-asparaginase was recombined with asp-pro-hGHRH(1-44) gene synthesized by PCR method to form one kind of fusion protein with unique acid labile linker Asp-Pro. The Pro-hGHRH(1-44) peptide was purified to homogeneity by means of cell disruption, washing, ethanol precipitation, acid hydrolysis, SP-Sephadex C-25, and Sephadex G-10 column chromatography. The peptide's molecular weight of 5,139 Da as measured by EIS-MS was coincident with the actual values. In the study of the activity, the doses of peptide were 0.1, 1.0, and 10 microg/ml for rat pituitary and 5 microg/ml for human pituitary. The peptide increased GH releases from rat pituitary in a concentration-dependent manner (P<0.05; P<0.01). At 1.0 microg/ml, there was a significant difference between Pro-Pro-hGHRH(1-44)-Gly-Gly-Cys and Pro-hGHRH(1-44) or Pro-Pro-hGHRH(1-44) (P<0.05), whereas the standard hGHRH(1-40) showed no measured rGH release. For human fetal pituitary, the Pro-hGHRH(1-44) peptides showed good GH-releasing activity, but there were no significant differences between them. The structure-activity relationship showed that for both rat and human fetal pituitary, the net GH-releasing activity of the Pro-hGHRH(1-44) analog was more than that of Pro-Pro-hGHRH(1-44). The results of the other hormones from human pituitary showed that the analog had good function-selectivity and species specificity.

Study on the constructions and activities of three novel hGHRH analogs with N-terminal prolyl modulation+.

Growth hormone releasing hormone is one of the hormones secreted by the hypothalamus. Because of its potential applications in agriculture and medicine, its short half-life and its expensive chemical synthesis, an analog with high GHRH activity and prolonged half-life has been looked for. The fusion partner gene with 127 amino acid residues of the C-terminus from L-asparaginase was recombined respectively with asp-pro-pro-hGHRH(1-44), asp-pro-hGHRH(1-44) or asp-1pro-GHRH(2-44) genes synthesized by PCR method to form three kinds of fusion proteins with unique acid labile linker Asp-Pro. The Pro-Pro-hGHRH(1-44), Pro-hGHRH(1-44), and 1Pro-GHRH(2-44) peptides were purified to homogeneity by means of cell disruption, washing of inclusion body, ethanol fraction precipitation, acid hydrolysis, SP-Sephadex C-25 and Sephadex G-10 column chromatography. The peptide molecular mass of 5235, 5139 or 4975 Da was determined by ESI mass spectroscopy and purity was determined by SDS-PAGE. In the study of in vitro activity, the antiserum kit against human GH and peptide doses of 0.1, 1.0 and 10 microg/ml were used. These peptides obviously increased GH releases both from human pituitary and from rat pituitary. The activity comparisons showed that there was significant difference between Pro-Pro-hGHRH(1-44)-Gly-Gly-Cys and Pro-Pro-hGHRH(1-44) at 1.0 microg/ml, or between 1Pro-hGHRH(2-44) and Pro-Pro-hGHRH(1-44) or Pro-hGHRH(1-44) at 10 microg/ml. The structure-activity relationships showed that at the original C-terminus, for rat pituitary the activity of the GHRH analog with 1Tyr-->Pro was more than that of Pro-Pro-hGHRH(1-44) or Pro-hGHRH(1-44). The results showed that the analogs had good GH-releasing activity and species specificity.

The Periosteal Autografts Transplantation for Cartilage Defects of the Hip in Older Children With Developmental Dysplasia as an Adjunctive Procedure.

Cartilage lesions are at a high prevalence in dysplastic hips and may relate to arthritic changes and hip joint dysfunction. To date, the effectiveness of repair of articular cartilage defects in the dysplastic hips has not yet been thoroughly evaluated. Here we retrospectively reviewed the effects of acetabuloplasty procedures with/without concomitant autologous tibial periosteal transplantation (ATPT) for articular cartilage defects of the hip in older children with developmental dysplasia of the hip (DDH).Older DDH children with focal cartilage defects of the acetabular or femoral cartilage or both in the hip joint were treated by acetabuloplasty procedures with (Group I) or without (Group II) concomitant ATPT to evaluate the improvements in range of motion (ROM), pain relief of hip, walking tolerability (WL), radiologic evaluations, and outcomes in the long-term follow-up.More satisfactory functional outcome is readily achieved among patients treated with combined acetabuloplasty and ATPT, evidenced by marked pain relief and improved ROM and WL. The latest favorable radiologic evaluation was 70.6% in Group I and 60.0% in Group II, respectively. More hips exhibited congruency between the femoral head and the shell, with less deformity of femoral head and acetabulum or narrowed joint space in Group I. Few major complications were recorded in Group I.Application of periosteal autograft for repair of cartilage defects within the hip joint might be an effective adjunctive treatment for acetabuloplasty in preventing stiffness, reducing pain, and improving ROM and outcomes in hip rehabilitation in the long-term follow-up in older children with DDH.

Electroacupuncture activates enteric glial cells and protects the gut barrier in hemorrhaged rats.

AIM: To investigate whether electroacupuncture ST36 activates enteric glial cells, and alleviates gut inflammation and barrier dysfunction following hemorrhagic shock. METHODS: Sprague-Dawley rats were subjected to approximately 45% total blood loss and randomly divided into seven groups: (1) sham: cannulation, but no hemorrhage; (2) subjected to hemorrhagic shock (HS); (3) electroacupuncture (EA) ST36 after hemorrhage; (4) vagotomy (VGX)/EA: VGX before hemorrhage, then EA ST36; (5) VGX: VGX before hemorrhage; (6) α-bungarotoxin (BGT)/EA: intraperitoneal injection of α-BGT before hemorrhage, then EA ST36; and (7) α-BGT group: α-BGT injection before hemorrhage. Morphological changes in enteric glial cells (EGCs) were observed by immunofluorescence, and glial fibrillary acidic protein (GFAP; a protein marker of enteric glial activation) was evaluated using reverse transcriptase polymerase chain reaction and western blot analysis. Intestinal cytokine levels, gut permeability to 4-kDa fluorescein isothiocyanate (FITC)-dextran, and the expression and distribution of tight junction protein zona occludens (ZO)-1 were also determined. RESULTS: EGCs were distorted following hemorrhage and showed morphological abnormalities. EA ST36 attenuated the morphological changes in EGCs at 6 h, as compared with the VGX, α-BGT and HS groups. EA ST36 increased GFAP expression to a greater degree than in the other groups. EA ST36 decreased intestinal permeability to FITC-dextran (760.5 ± 96.43 ng/mL vs 2466.7 ± 131.60 ng/mL, P < 0.05) and preserved ZO-1 protein expression and localization at 6 h after hemorrhage compared with the HS group. However, abdominal VGX and α-BGT treatment weakened or eliminated the effects of EA ST36. EA ST36 reduced tumor necrosis factor-α levels in intestinal homogenates after blood loss, while vagotomy or intraperitoneal injection of α-BGT before EA ST36 abolished its anti-inflammatory effects. CONCLUSION: EA ST36 attenuates hemorrhage-induced intestinal inflammatory insult, and protects the intestinal barrier integrity, partly via activation of EGCs.