Catalpol improves impaired neurovascular unit in ischemic stroke rats via enhancing VEGF-PI3K/AKT and VEGF-MEK1/2/ERK1/2 signaling.

Neurovascular unit (NVU) is organized multi-cellular and multi-component networks that are essential for brain health and brain homeostasis maintaining. Neurovascular unit dysfunction is the central pathogenesis process of ischemic stroke. Thus integrated protection of NVU holds great therapeutic potential for ischemic stroke. Catalpol, classified into the iridoid monosaccharide glycoside, is the main active ingredient of the radix from traditional Chinese medicine, Rehmannia glutinosa Libosch, that exhibits protective effects in several brain-related diseases. In the present study, we investigated whether catalpol exerted protective effects for NVU in ischemic stroke and the underlying mechanisms. MCAO rats were administered catalpol (2.5, 5.0, 10.0 mg·kg-1·d-1, i.v.) for 14 days. We showed that catalpol treatment dose-dependently reduced the infarction volume and significantly attenuated neurological deficits score in MCAO rats. Furthermore, catalpol treatment significantly ameliorated impaired NVU in ischemic region by protecting vessel-neuron-astrocyte structures and morphology, and promoting angiogenesis and neurogenesis to replenish lost vessels and neurons. Moreover, catalpol treatment significantly increased the expression of vascular endothelial growth factor (VEGF) through up-regulating PI3K/AKT signaling, followed by increasing FAK and Paxillin and activating PI3K/AKT and MEK1/2/ERK1/2 pathways. The protective mechanisms of catalpol were confirmed in an in vitro three-dimensional NVU model subjected to oxygen-glucose deprivation. In conclusion, catalpol protects NVU in ischemic region via activation of PI3K/AKT signaling and increased VEGF production; VEGF further enhances PI3K/AKT and MEK1/2/ERK1/2 signaling, which may trigger a partly feed-forward loop to protect NVU from ischemic stroke.

Sonographic features of secondary involvement of skin and subcutaneous tissues by hematologic malignancies.

OBJECTIVES: To evaluate the sonographic features of secondary involvement of skin and subcutaneous tissues by hematologic malignancies. METHODS: A review of the ultrasound and pathology databases yielded 10 cases with 13 skin and subcutaneous tissue lesions secondary to hematologic neoplasms, which were confirmed by pathology. We used ultrasound to assess the number, location, size, depth of involvement, echogenicity, and vascularity of the lesions. RESULTS: The study involved five male and five female patients, including four leukemia, two multiple myeloma, and four lymphoma patients. The average age was 45 years (17-66 years). Three patients presented with one lesion, four with two lesions, and three with more than two lesions. All the lesions were located in the trunk and extremities. The lesions ranged from 1.2 to 8.3 cm in size. A total of 10 lesions involved subcutaneous fat tissue. A total of 10 lesions displayed hypoechoic foci within a hyperechoic background, and three appeared hypoechoic, and most of them exhibited abundant vascularity (12 of 13 lesions). CONCLUSIONS: Secondary involvement of skin and subcutaneous tissues by hematologic malignancies often present with multiple palpable masses showing the following ultrasound features: (1) subcutaneous fat infiltration, (2) hypoechoic foci with a hyperechoic background, and (3) abundant vascularity.

Pre-harvest sprouting in cereals: genetic and biochemical mechanisms.

With the growth of the global population and the increasing frequency of natural disasters, crop yields must be steadily increased to enhance human adaptability to risks. Pre-harvest sprouting (PHS), a term mainly used to describe the phenomenon in which grains germinate on the mother plant directly before harvest, is a serious global problem for agricultural production. After domestication, the dormancy level of cultivated crops was generally lower than that of their wild ancestors. Although the shortened dormancy period likely improved the industrial performance of cereals such as wheat, barley, rice, and maize, the excessive germination rate has caused frequent PHS in areas with higher rainfall, resulting in great economic losses. Here, we systematically review the causes of PHS and its consequences, the major indicators and methods for PHS assessment, and emphasize the biological significance of PHS in crop production. Wheat quantitative trait loci functioning in the control of PHS are also comprehensively summarized in a meta-analysis. Finally, we use Arabidopsis as a model plant to develop more complete PHS regulatory networks for wheat. The integration of this information is conducive to the development of custom-made cultivated lines suitable for different demands and regions, and is of great significance for improving crop yields and economic benefits.

Effect of Hydrogen Sulfide on the Mitogen-Activated Protein Kinase Signaling Pathway in Cultured Skin Macrophages of Burned Rats.

BACKGROUND: This study aims to investigate the effect of hydrogen sulfide on the mitogen-activated protein kinases signaling pathway in in vitro cultured skin macrophages of burned rats. MATERIALS AND METHODS: Thirteen healthy Sprague-Dawley rats were divided into five groups: normal control group, burned control group, sodium hydrogen sulfide group, glibenclamide group, and sodium hydrogen sulfide + glibenclamide group. The burned rats were made into a deep II° 5% total body surface area flame burn injury model. The skin basement macrophages were separated from the skin of normal rats and the wound skin of burned rats and cultured. At 1, 6, and 12 h after intervention, extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and p38 protein levels were detected by Western blot, and ERK, p38, and JNK messenger RNA (mRNA) levels were detected by reverse transcription polymerase chain reaction. RESULTS: Differences in ERK, p38, and JNK mRNA and protein levels between the normal control group and burned control group were statistically significant (P < 0.05). At the same time point, the ERK, p38, and JNK mRNA and protein levels in the NaSH group were different from those in other groups, and the differences were statistically significant (P < 0.05). CONCLUSIONS: Hydrogen sulfide has a regulatory effect on ERK, JNK, and p38 in the mitogen-activated protein kinases signaling pathway in macrophages of burned rats.

[Exploration on mechanism of anti-influenza virus activity of genus Paeonia based on network pharmacology].

This paper aimed to investigate the anti-influenza virus activity of the genus Paeonia, screen potential anti-influenza virus compounds and predict targets of anti-influenza virus to explore the mechanism of anti-influenza virus activity. First of all, a total of 301 compounds of the genus Paeonia were summarized from the literatures in recent ten years. The candidate active ingredients from the genus Paeonia were identified by database such as PubChem and Chemical Book. The ligands were constructed by ChemDraw, Avogadro and Discovery Studio Visualizer. Secondly, 23 potential anti-influenza virus targets were developed by combining the target database and the literatures. Uniprot database was used to find the anti-influenza virus targets, and RCSB was used to identify targets associated with anti-influenza virus activity as docked receptor proteins. QuickVina 2.0 software was used for molecular docking. Finally, the Cytoscape 3.5.1 software was used to map the potential activity compounds of the genus Paeonia against influenza virus and the anti-influenza virus target network. Uniprot online database was used to analyze the target GO enrichment and KEGG metabolic pathways. The results showed that 74 compounds of the genus Paeonia had anti-influenza virus effect and 18 potential anti-influenza virus targets were screened. GO analysis concluded that the mechanism of the genus Paeonia anti-influenza virus is consistent with the mechanism of NA anti-influenza virus in order to stop the sprouting, dispersion and diffusion of virus and reduce the ability of virus to infect, so that the infection can be restricted so as to achieve the anti-influenza virus effect.

[Effect factors and mechanisms of borneol's bidirectional regulation on blood-brain barrier permeability].

In recent twenty years, there are a lot of studies about the effect of borneol on permeability of blood-brain barrier(BBB); however, it isDODOrt of regular conclusions of effect factors and in-depth analysis of functional mechanisms. The current researching data were collected and analyzed in this paper for illuminating the effect factors and mechanisms of borneol on permeability of BBB.The following conclusions were obtained: five factors about borneol influencing the permeability of BBB. First, opticity activity of borneol had no significant effect on action effects. Second, dose of borneol in the range of 50.00-200.00 mg•kg⁻¹, did not affect the effect direction, but only affect its action intensity either with use alone or combination use. Third, the borneol can increase the permeability of physiological BBB, and decrease the permeability of pathological BBB. Fourth, regardless of using singly or using compatibility with musk, borneol can decrease the permeability of BBB in different brain disease models. Fifth, when used with astragalus, catalpol or puerarin, borneol can increase the permeability of BBB and promote the drugs through BBB in pathological conditions. The target spots and mechanisms of borneol's bidirectional regulation on the permeability of BBB are related to the structure and function of cerebral endothelial cells, the exocytosis effects of P-gp and low pinocytosis internal transport effects. On one hand，borneol can down-regulate P-gp by inhibiting NF-κB to reduce the exocytosis effects of P-gp and promote the blood brain barrier pinocytosis to increase the permeability of BBB; On the other hand，borneol can reduce the degradation of basement membrane of blood vessel and tight junctions by inhibiting the expression of IL-1ß, MMP-9 to decrease the permeability of BBB；moreover，borneol has bidirectional regulation effects on blood-brain barrier permeability by influencing the signaling pathways of Ca2+-eNOS-NO, VEGF-eNOS-NO. However, the detailed mechanisms that borneol regulates and controls the permeability of BBB are so complicated, so they shall be further proved and clarified.

[Siwu decoction improves iron deficiency anemia in infant rats and regulates iron metabolism].

To investigate the effect of Siwu decoction on improving iron deficiency anemia in infant rats and observe its regulatory effects on iron metabolism. SD rats were fed with low iron fodder for 2 weeks, and then the rats with hemoglobin level less than 75 g•L ⁻¹ were screened out and randomly divided into model group, Ferrous succinate 50 mg•kg ⁻¹ group, Siwu decoction 4 g•kg ⁻¹, 8 g•kg ⁻¹ and 16 g•kg ⁻¹ groups. After 4 weeks' gavage administration, Wright-Giemsa's staining of blood smear and HE staining of the livers were conducted, and all rats were tested for blood routine, serum iron, total iron binding capacity, serum ferritin, serum hepcidin and liver hepcidin. The expression levels of liver ferritin, transferrin and transferrin receptor 1 were also detected. The results showed that as compared with normal group, the activity level of model group was decreased, and the color and lustre of auricles and toes were pale white; the number of red blood cells was decreased; the volume was smaller, with an increased zone of central pallor; the body weight and blood routine parameters were decreased significantly; the livers were pale red, and the hepatic cords around thecentral veins were unclear and misaligned; the serum iron, serum ferritin, liver iron levels and the expression of liver ferritin were decreased significantly; the total iron binding capacity, serum hepcidin, liver hepcidin, the expression levels of liver transferrin and transferrin receptor 1 were significantly increased, indicating successful establishment of models. As compared with the model group, activity was increased in Siwu decoction group; the color and lustre of auricles and toes were ruddy; the number of red blood cells was increased; the volume was larger, with a decreased zone of central pallor; the body weight and blood routine parameters were increased significantly; the livers were red, hepatic cords around the central veins were clear and aligned;the serum iron, serum ferritin, liver iron levels and the expression of liver ferritin were significantly increased, the total iron binding capacity, serum hepcidin, liver hepcidin, the expression of liver transferrin and transferrin receptor 1 were decreased significantly. The results demonstrated that Siwu decoction had a certain effect on improving iron deficiency anemia in infant rats, and the mechanism may be associated with the regulatory effect of hepcidin iron metabolism.

[Comprehensive regulation effect of traditional Chinese medicine on proliferation and differentiation of neural stem cells].

Since the discovery of neural stem cells(NSCs) in embryonic and adult mammalian central nervous systems, new approaches for proliferation and differentiation of NSCs have been put forward. One of the approaches to promote the clinical application of NSCs is to search effective methods to regulate the proliferation and differentiation. This problem is urgently to be solved in the medical field. Previous studies have shown that traditional Chinese medicine could promote the proliferation and differentiation of NSCs by regulating the relevant signaling pathway in vivo and in vitro. Domestic and foreign literatures for regulating the proliferation and differentiation of neural stem cells in recent 10 years and the reports for their target and signaling pathways were analyzed in this paper. Traditional Chinese medicine could regulate the proliferation and differentiation of NSCs through signaling pathways of Notch, PI3K/Akt, Wnt/ß-catenin and GFs. However, studies about NSCs and traditional Chinese medicine should be further deepened; the mechanism of multiple targets and the comprehensive regulation function of traditional Chinese medicine should be clarified.

Thermography and machine learning techniques for tomato freshness prediction.

The United States and China are the world's leading tomato producers. Tomatoes account for over $2 billion annually in farm sales in the U.S. Tomatoes also rank as the world's 8th most valuable agricultural product, valued at $58 billion dollars annually, and quality is highly prized. Nondestructive technologies, such as optical inspection and near-infrared spectrum analysis, have been developed to estimate tomato freshness (also known as grades in USDA parlance). However, determining the freshness of tomatoes is still an open problem. This research (1) illustrates the principle of theory on why thermography might be able to reveal the internal state of the tomatoes and (2) investigates the application of machine learning techniques-artificial neural networks (ANNs) and support vector machines (SVMs)-in combination with transient step heating, and thermography for freshness prediction, which refers to how soon the tomatoes will decay. Infrared images were captured at a sampling frequency of 1 Hz during 40 s of heating followed by 160 s of cooling. The temperatures of the acquired images were plotted. Regions with higher temperature differences between fresh and less fresh (rotten within three days) tomatoes of approximately uniform size and shape were used as the input nodes for ANN and SVM models. The ANN model built using heating and cooling data was relatively optimal. The overall regression coefficient was 0.99. These results suggest that a combination of infrared thermal imaging and ANN modeling methods can be used to predict tomato freshness with higher accuracy than SVM models.

[Borneol promotes catalpol and puerarin crossing through blood-brain barrier in focal cerebral ischemic rats].

Previous studies showed that borneol could promote some drugs crossing through the blood-brain-barrier (BBB) at certain conditions. However, the mechanism has not been clarified yet. This study aimed to investigate the effect of bornrol on promoting catalpol and puerarin through BBB and explore the relevant mechanism. The focal cerebral ischemic rats were divided into 7 groups randomly and then were administered corresponding drugs: model group (M, solvent), catalpol-puerarin group (ZG, catalpol 45 mg•kg⁻¹+puerarin 200 mg•kg⁻¹), catalpol-puerarin-bornrol group(ZGB, catalpol 45 mg•kg⁻¹+puerarin 200 mg•kg⁻¹ +bornrol 200 mg•kg⁻¹), catalpol-bornrol group(ZB, catalpol 45 mg•kg⁻¹ +bornrol 200 mg•kg⁻¹), puerarin-bornrol group(GB, puerarin 200 mg•kg⁻¹ +bornrol 200 mg•kg⁻¹), butoxamine-ZG group(BTX+ZG, butoxamine 1.5 mg•kg⁻¹+ catalpol 45 mg•kg⁻¹+puerarin 200 mg•kg⁻¹), and butoxamine-ZGB group(BTX+ZGB, butoxamine 1.5 mg•kg⁻¹+ catalpol 45 mg•kg⁻¹+puerarin 200 mg•kg⁻¹ +bornrol 200 mg•kg⁻¹). Another 10 sham-operated rats were set as control (S). Ten minutes after the administration, the cerebrospinal fluid was taken to test the content of catalpol and puerarin, and the brain tissue was taken to test the expression of ß2-adrenergic receptor, eNOS, and NO. Compared with the M group, the ZG group showed content of catalpol is 26.673 µg•L⁻¹ and the content of puerarin is below the detection limit;the expression levels of ß2-adrenergic receptor, eNOS and the contents of NO in brain tissue are no significant difference. Compared with the ZG group, the ZGB, ZB and GB groups showed significantly increased content of catalpol andpuerarin, as well as the expression of ß2-adrenergic receptor, eNOS and NO in the brain tissue (P<0.05). The content of catalpol in BTX+ZG group changed non-significantly. Compared with the ZGB group, the BTX+ZGB group presented significantly decreased content of catalpol and puerarin and reduced expression of eNOS and NO in the brain tissue (P<0.05）.The results demonstrated that borneol could dramatically promote catalpol and puerarin crossing through BBB in the focal cerebral ischemic rats. Moreover, the effect may be related to the up-regulation of ß2-adrenergic receptor and the increasing expression of eNOS and NO.

[Effect of zige lyophilized powder for injection in improving acute cerebral microcirculation disturbance in rats].

OBJECTIVE: To investigate the effect of Zige lyophilized powder for injection in improving the acute cerebral microcirculation disturbance in rats. METHOD: Window craniotomy was performed for rats after the drug administration for 14 days. The experimental microcirculation disturbance model was duplicated with high molecule dextran. After the drug administration, the micro-vein diameters of cerebral pla mater of various groups were observed and recorded under the biological microscope. The blood flow volume was monitored by laser Doppler flow-meter. HCT was measured by the electric resistance method. The hemorheological indexes were detected by the auto-hemorheological instrument. RESULT: Zige lyophilized powder for injection (16.40, 32.70, 65.40 mg x kg(-1)) could significantly expand the micro-vein diameter of cerebral pla mater, improve the downward trend of the blood flow volume, and reduce the various hemorheological indexes. CONCLUSION: Zige lyophilized powder for injection shows the effect in improving the cerebral microcirculation.

Yak meat content in feed and its impact on the growth of rats.

To evaluate the effects of varying proportions of yak meat in feed on the growth of rats and provide a theoretical basis for selecting the optimal feed proportion suitable for rats. This study was designed as a one-variable experiment. Fifty male rats were divided into five groups. The ratios of yak meat to basal feed of rats in four dietary treatment groups were 2:8, 4:6, 6:4, and 8:2, respectively, while those in the control group were only provided a basal diet. In the feeding experiment, the body weights of the rats were recorded on Day 0 and subsequently in the first, second, third, and fourth weeks, along with quantities of feed intake. The body and tail lengths, as well as the waist circumference of the rats, were measured, and blood samples were collected in the fourth week for routine blood and biochemistry investigations. The rats in the 4:6 feed group had the best body condition. They had normal body and tail lengths, smaller waist circumferences, good posture, and were in better overall health than rats in the other groups. The results indicate that the 4:6 diet was optimal for enhancing rats' growth performance compared to the other diets.

Effect of Yak Meat to the Daily Ration of Scalded Rats for Wound Healing.

Objective: Treatment of burn wound healing involves infection, nutrition, psychology and rehabilitation, and proper nutritional support can promote wound healing, enhance immune function and reduce the incidence of complications. This study aimed to investigate the effects of feed containing yak meat on scalded rats' body condition and wound healing. Methods: Adopting a two-factor factorial design, the growth performance, food intake, body weight, and Lee's index of rats were measured. The wound conditions of scalded rats with different feeds (basic, basic + yak meat, and basic + yellow beef) were observed at different periods, and their wounds' hematoxylin and eosin (H&E) staining states were detected. The proliferating cell nuclear antigen (PCNA)-positive cells and apoptosis were analyzed to evaluate the effects of feed on the wound healing of scalded rats. Results: The feed intake was the highest in the yellow beef feed group and the lowest in the yak meat feed group. The body weight was the highest in the yak meat feed group and the lowest in the yellow beef feed group. Furthermore, 45 days after scalding, the obesity index in the yak beef feed group was the closest to that of the rats before scalding. The wound recovery of the rats in the yak meat feed group was the best at 30 days, and the H&E staining results also proved that the recovery effect of the scalded rats in the yak meat feed group was better than other two groups. According to the results of PCNA and apoptosis, the yak meat feed group had lower positive cell rate and faster wound healing. Conclusion: The rats in the yak meat feed group recovered better than those in the other groups, and the yak beef feed had the best effect on the wound healing of the scalded rats.

[Protective effects of salidroside on vascular endothelial cells in rats with frostbite after chronic hypoxia].

Objective: To investigate the protective effects of salidroside on endothelial cells in rats with frostbite after chronic hypoxia. Methods: Healthy male SD rats, randomly divided into 3 groups with 10 rats in each group, which included the sham injury group, the model group, and the model +salidroside group. The rats in each group were placed in a composite low-pressure chamber to simulate a environment with a pressure of 54.1 kpa and a temperature of 23~25°C. The rats were exposed to hypoxia under these conditions for 14 days, during the experimental time the rats in the model+salidroside group were treated with 50 mg/kg salidroside daily. After the rats were removed from the low-pressure chamber, except for the sham injury group, frozen iron sheets were applied tightly to the back of the rats for 30 s, supplemented with low temperature for frostbite modeling. Blood and skin tissues were collected at 12 hours after modeling for testing. The structural changes in tissue and vascular endothelial cells were observed in the frostbite region. Vascular endothelial cell particulate EMP levels were detected. The levels of ICAM-1, sEPCR, vWF, ET-1 and NO secretion were determined. The expression levels of HIF-1α, p-PI3K, p-Akt and VEGF were detected by Western blot. Results: Salidroside could effectively reduce skin collapse in frostbitten areas. It could reduce the injury of frostbitten tissues, and improve the subcutaneous tissue necrosis and inflammatory cell infiltration. The autophagy of vascular endothelial cells was reduced. Compared with the model group (0.250±0.165)%, the expression of EMPs in the model+salidroside group (2.453±0.196)% was increased significantly (P＜0.01). In addition, the contents of NO (2.622±0.219)pg/ml was also significantly higher than that of the model group (1.616±0.152)pg/ml (P＜0.01), and the content of vWF (233.50±13.43)pg/ml was lower than that of the model group (315.60±8.78)pg/ml (P＜0.05). There was no significant difference in the levels of ICAM-1, sEPCR and ET-1. Salidroside significantly decreased the expressions of p-PI3K, p-Akt, VEGF and HIF-1α protein in vascular endothelial cells of rats with frostbite (P＜0.01). Conclusion: Salidroside can reduce endothelial cell damage, reduce endothelial cell autophagy and promote endothelial cell regeneration. Based on the PI3K/Akt pathway, salidroside has a good protective effect on endothelial cells of rats with frostbite after chronic hypoxia.

Systemic treatment for severe concentrated sulfuric acid burns in an adult male at high altitude: A case report.

BACKGROUND: The aim of this study was to report a case of a patient who suffered from severe concentrated sulfuric acid burns while working at high altitude. This patient recovered after systemic treatment. We also provide a literature review for a better understanding of the disease. CASE SUMMARY: A 30-year-old male, who was working in a local chemical plant in Xining (the Qinghai provincial capital, China) at an altitude of 2261 m, suffered from burns 85% TBSA (III° 70%TBSA, deep II° 15%TBSA) after a tank containing 80% concentration of sulfuric acid exploded. The patient immediately received a series of first aid treatments, as well as rigorous wound managements after admission, which included protection for the whole body and organs, prevention and treatment of eye burns, and the appropriate oxygen therapy. After 65 d of treatment, the burn wounds had completely healed, and the patient was transferred to another specialized hospital for further eye treatment. The first aid before admission and the emergency treatment of wounds following admission were appropriate. No severe complications of sepsis, severe renal insufficiency, septic costal chondritis, corneal perforation or other burns occurred during the treatment. CONCLUSION: The main causes of concentrated sulfuric acid burns consisted of accidental burns at work, accidents in the outside, factitious injuries and improper laboratory operations. The clinical manifestations were mostly deep II° and III° burns, with a formation of brown-black, leather-like eschar on the wound surface and locally embolized dendrite-like vessels. The clear cause of the injury and typical clinical manifestations in this case made it easy to diagnosis. However, adult cases with severe concentrated sulfuric acid burns in high altitude areas are rare, so the successful treatment of this case is of great significance.

hTERT promotes the invasion of telomerase-negative tumor cells in vitro.

Telomerase activation is a common feature of most types of human cancers. Although several studies have shown that activation of telomerase might participate in the progression of tumors, the mechanism by which telomerase activation causes the invasion and metastasis of tumors remains unclear. In this study, we transfected a vector containing the full-length cDNA of hTERT into a telomerase-negative osteosarcoma cell line U2OS (hTERT/U2OS). Vacant vector-transfected U2OS cells served as a control (EGFP/U2OS). We then compared the biological and vitodynamic changes in these transfected and untransfected U2OS cells. The hTERT protein was detected in hTERT/U2OS cells by Western blot analysis and immunochemistry assay. The telomere length in hTERT/U2OS cells was longer than that in EGFP/U2OS and untransfected U2OS cells. We also found using vacuum micropipette aspiration that hTERT transfection did not only promote the proliferation of hTERT-transfected U2OS cells but also increased the cellular adhesion capacity to the extracellular matrix. Transwell matrigel assay confirmed an increased invasion ability in hTERT/U2OS cells. These results strongly suggest that hTERT transfection promotes the invasion of telomerase-negative cells. Telomerase-mediated telomere maintenance enables these cells to achieve a fully malignant endpoint, including invasion and metastasis.

[Residues and Spatial Distribution Characteristics of Organochlorine Pesticides DDTs in Soil of Linyi City, Shandong Province].

Surface soil samples were collected every 36 km2 from Linyi City to study the residues, composition and origin, influencing factors, spatial distribution and environment quality characteristics of soil DDTs. Measurements were taken for DDTs, OrgC, N, etc. for all samples. The results indicated that the detectable rate of DDTs was 71. 75%, and the mean content of DDTs was 0. 035 µg.g-1. p,p'-DDT and p,p'-DDE were the predominant contaminant compounds, with mean concentrations of 0.033 µg.g-1 and 0.010 µg.g-1, and accounted for 60. 99% and 34. 62% of the detectable samples, respectively. The degradation rate of DDTs suggested that 58% surface soils were recently inputted, these newly inputted locations were especially distributed in the middle to south of the study area, meanwhile, p,p'-DDD/p,p'-DDE revealed that the degradation of DDTs was mainly under oxidizing condition, and o,p'-DDT/p,p'-DDT illustrated that 71. 37% DDTs in soils of the study area were concerned with technical DDTs sources. Besides, the correlation, analysis showed that the external factors affecting the distribution of DDTs included OrgC, N, C and pH etc. and the higher the p, p'-DDT proportion of DDTs, the greater the effect. The distribution of DDTs had an obvious point source characteristic, and significant concentration centers were located nearby the cities and counties, typically, the DDTs concentrations of middle to southern area were much higher. However, DDTs environmental quality assessment suggested that the pollution level was relatively low, and the soil was mainly classified into grade I or II, which accounted for 78. 95% and 21. 05% of the whole study area, respectively.

[Influence of hydrogen sulfide on important organs in rats with severe burn].

OBJECTIVE: To investigate the changes in hydrogen sulfide (H2S) and cystathionine gamma-lyase (CSE) in rats with severe burn, and to analyze the effects on important organs. METHODS: One hundred and four healthy male SD rats were divided into normal control group (NC, n = 8), burn group (B, n = 48), and H2S intervention group (HI, n = 48) according to the random number table. SD rats in HI group were intraperitoneally injected with NaHS (56 micromol/kg) once a day for 5 days. Then rats in HI and B groups were subjected to 30% TBSA full-thickness burn. Blood sample as well as heart, liver, lung, kidney, and stomach tissue samples were harvested from rats in B group at post burn hour (PBH) 2, 6, 12, 24, 48, and 96 respectively for determination of serum content of H2S and CSE activity. Serum content of alanine transaminase (ALT), aspartate aminotransferase (AST), MB isoenzyme of creatine kinase (CK-MB), urea nitrogen (BUN), and creatinine (Cr) in HI and B groups were examined at each time point. Samples were harvested from above organs in each group for histomorphological observation. Above-mentioned indexes were also determined in NC group as control. Data were processed with SNK- q test, t test, correlation analysis (between serum content of H2S and CSE activities, biochemical indexes). RESULTS: Serum content of H2S and CSE activities of above organs (except for lung tissue at PBH 48, 96) in B group within PBH 96 were lower than those in NC group, reaching minimum values at PBH 6 or 12. Compared with those in NC group, serum contents of all biochemical indexes in B group were obviously increased within PBH 48, in which serum contents of BUN [(32.5 +/- 9.8) mmol/L] and Cr [(65 +/- 9) micromol/L] reached peak at PBH 6, and serum contents of ALT [(423 +/- 59) U/L], AST [(993 +/- 60) U/L], and CK-MB [(49 261 +/- 6637) U/L] peaked at PBH 12. Serum contents of all biochemical indexes in HI group at each time point were significantly decreased as compared with those in B group, but the same change tendencies were showed in both groups. Histomorphological observation showed that all the organs were severely injured in B group at PBH 24, whereas those in HI group were markedly ameliorated. Serum content of H2S in B group was respectively correlated with CSE activities of all organs (with r value from 0.639 to 0.894, P values all below 0.005) and serum contents of biochemical indexes (with r value from 0.301 to 0.585, P values all below 0.001). CONCLUSIONS: H2S/CSE system may take part in pathophysiological process in rats with severe burn. Exogenous H2S replacement therapy can protect important organs of rats with severe burn.