Dunaliella Ds-26-16 acts as a global regulator to enhance salt tolerance by coordinating multiple responses in Arabidopsis seedlings.

MAIN CONCLUSION: Based on phenotypic, physiological and proteomic analysis, the possible mechanism by which Ds-26-16 regulates salt tolerance in Arabidopsis seedlings was revealed. Functional and mechanistic characterization of salt tolerance genes isolated from natural resources is crucial for their application. In this study, we report the possible mechanism by which Ds-26-16, a gene from Dunaliella, and its point mutation gene EP-5, enhance salt tolerance in Arabidopsis seedlings. Both Ds-26-16 and EP-5 transgenic lines displayed higher seed germination rates, cotyledon-greening rates, soluble sugar contents, decreased relative conductivity and ROS accumulation when germinating under 150 mM NaCl conditions. Comparative proteomic analysis revealed that there were 470 or 391 differentially expressed proteins (DEPs) in Ds-26-16 or EP-5, respectively, compared with the control (3301) under salt stress. The GO and KEGG enrichment analyses showed the DEPs in Ds-26-16 vs. 3301 and EP-5 vs. 3301 were similar and mainly enriched in photosynthesis, regulation of gene expression, carbohydrate metabolism, redox homeostasis, hormonal signal and defense, and regulation of seed germination. Thirty-seven proteins were found to be stably expressed under salt stress due to the expression of Ds-26-16, and eleven of them contain the CCACGT motif which could be bound by the transcription factor in ABA signaling to repress gene transcription. Taken together, we propose that Ds-26-16, as a global regulator, improves salt-tolerance by coordinating stress-induced signal transduction and modulating multiple responses in Arabidopsis seedlings. These results provide valuable information for utilizing natural resources in crop improvement for breeding salt-tolerant crops.

Os4BGlu14, a monolignol ß-Glucosidase, negatively affects seed longevity by influencing primary metabolism in rice.

KEY MESSAGE: Os4BGlu14, a monolignol ß-glucosidase, plays a negative role in seed longevity by affecting primary metabolism during seed development and aging. Seed longevity is a crucial trait in agriculture and in the conservation of germplasm resources. ß-Glucosidases (BGlus) are multifunctional enzymes that affect plant growth and their adaptation to the environment. The function of rice BGlus in seed longevity, however, remains unknown. We report here that Os4BGlu14, a rice ß-Glucosidase, negatively affected seed longevity during accelerated aging. Os4BGlu14 was highly expressed in rice embryos and induced by accelerated aging. Compared to the wild type, rice lines overexpressing Os4BGlu14 had significantly greater grain length, but smaller grain width and thickness. Overexpressing (OE) lines also showed lower starch but higher glucose contents. After accelerated aging treatment, OE lines displayed a significantly lower germination percentage than the wild type. Additionally, these lines had higher lignin accumulation before and after accelerated aging. Metabolome analysis detected 217 metabolites in untreated and aged rice seeds. Comparison of the differential metabolites between WT and OE5 revealed that ten key metabolites, four of which (e.g., uridine 5'-diphosphoglucose-glucose, UDPG) were increased, while the other six (e.g., γ-aminobutyric acid and methionine) were decreased, might be the crucial factors that lead to seed deterioration. Further analysis confirmed higher UDPG levels and more severe programmed cell death in OE lines than in the wild type. Furthermore, OE lines presented a lower germination rate after abscisic acid and paclobutrazol treatment during germination, compared to the wild type. Our study provides a basis for understanding the function of Os4BGlu14 in seed longevity in rice.

Cloning and molecular characterization of the ORF5 gene from a PRRSV-SN strain from Southwest China.

To monitor the genetic variation of PRRSV, the ORF5 gene of the PRRSV-SN strain found in Suining City, Sichuan Province, was cloned and sequenced. The results showed that the PRRSV-SN strain was a highly pathogenic PRRSV (HP-PRRSV) variant strain with the North American (NA) genotype. Homology analysis showed that the ORF5 gene of the PRRSV-SN isolate shared 89.4% (86.5%) nucleotide (amino acid) sequence similarity with the North American strain VR-2332, 98.8% (96%) similarity with JXA1, and 63.8% (57.7%) similarity with the European type representative strain Lelystad virus. Phylogenetic analysis showed that PRRSV-SN belongs to the NA genotype and has the same subtype as other highly pathogenic PRRSV strains. Amino acid sequence analysis showed that compared with the VR2332 strain, PRRSV-SN has different degrees of variation in the signal peptide, transmembrane region (TM), primary neutralizing epitope (PNE), non-neutral epitopes and N-glycosylation sites. Antigenicity analysis showed that the PRRSV-SN ORF5 gene products and JXA1 have similar antigenic characteristics, and the antigenic epitopes are mainly located in aa30-39, aa50-60, aa128-141, aa146-155 and aa161-183 regions. In contrast, the antigenic characteristics of PRRSV-SN are quite different from those of the VR2332 strain. The main differences were that the PRRSV-SN strain was significantly narrower than the VR2332 strain in the aa30-39 and the aa50-60 regions but was significantly wider in the aa136-141 region. The results of this study showed that the epidemic strains that cause PRRSV outbreaks in the farm are still mainly JXA1 variants, but due to the more frequent use of live vaccine immunizations, the genes of the PRRSV epidemic strain still show constant variation. Vaccination with live PRRSV should be reduced, and surveillance of PRRSV strains should be enhanced.

[Excessive endoplasmic reticulum stress mediates brain damage in hypoxia hypercapnia induced pulmonary hypertension rats].

The purpose of the present study was to investigate the effect of excessive endoplasmic reticulum stress (ERS) on the brain damage in hypoxia hypercapnia induced pulmonary hypertension (HHPH) rats. Forty healthy SPF male SD rats were randomly divided into four groups (n = 10 for each): control group, hypoxia hypercapnia group, ERS pathway agonist tunicamycin (TM) group and ERS pathway inhibitor 4-phenylbutyric acid (4-PBA) group. The rats of control group lived in normal environment, while the rats of other three groups were raised for four weeks in the tank with 8.5%-11% O2 and 5%-6% CO2. TM (0.08 mg/kg, twice a week) and 4-PBA (80 mg/kg, daily) were respectively intraperitoneally injected into the rats of TM and 4-PBA groups, and the hypoxia hypercapnia group was given the same volume of normal saline. The mean pulmonary artery pressure and heart perfusion of the rats were determined and recorded after four-week raising. Then the brain tissue of the rats were quickly taken out for the brain water content measuring and morphological changes observing. The Caspase-3 activity and the apoptotic index of the brain cells were also determined. The protein and mRNA expressions of p-JNK, Caspase-12, CHOP and GRP78 in brain tissues were detected by Western blot and RT-PCR. The results showed that compared with the control group, the mean pulmonary artery pressure, brain water content and brain cells apoptotic index, Caspase-3 activity, the protein and mRNA levels of p-JNK, Caspase-12, CHOP and GRP78 were increased (P < 0.05), and the brain tissues of the rats were obviously damaged in the rats raised in the hypoxia hypercapnia environment; compared with hypoxia hypercapnia group, the mean pulmonary artery pressure, brain water content, brain apoptotic index and Caspase-3 activity, p-JNK, Caspase-12, CHOP, GRP78 protein and mRNA expressions in TM group were increased (P < 0.05), and the brain tissues of the rats were obviously damaged, while all above changes were relieved in 4-PBA group (P < 0.05). These results suggest that excessive ERS may participate in the brain injury induced by HHPH in rats and inhibition of excessive ERS can relieve the brain injury in the rats with HHPH.

[Role of TRPC6 in pulmonary artery smooth muscle cells proliferation and apoptosis under hypoxia and hypercapnia].

The present study was to investigate the role of TRPC6 in pulmonary artery smooth muscle cells (PASMCs) proliferation and apoptosis under hypoxia and hypercapnia. PASMCs were isolated from chloral hydrate-anesthetized male Sprague-Dawley (SD) rats. Cellular purity was assessed by immunofluorescence staining for smooth muscle α-actin under fluorescence microscopy. Passage 4-6 PASMCs were starved for 24 h in serum-free DMEM and divided into 5 groups randomly: normoxia, hypoxia and hypercapnia, DMSO, TRPC6 inhibitor SKF-96365 and TRPC6 activator OAG groups. The normoxic group was incubated under normoxia (5% CO2, 21% O2, 37 °C) for 24 h, and the others were incubated with corresponding drugs under hypoxic and hypercapnic (6% CO2, 5% O2, 37 °C) atmosphere for 24 h. TRPC6 mRNA was detected by reverse transcription-PCR. TRPC6 protein was detected by Western blotting. The proliferation of PASMCs was performed by CCK-8 kit. Apoptosis of the PASMCs was detected using TUNEL assay. The [Ca2+]i in the PASMCs was measured using Fura 2-AM fluorescence. The results showed that the expressions of TRPC6 mRNA and protein, and [Ca2+]i were upregulated under hypoxic and hypercapnic conditions. Hypoxia and hypercapnia promoted cellular proliferation and inhibited apoptosis in the PASMCs. OAG enhanced the above-mentioned effects of hypoxia and hypercapnia, whereas SKF-96365 reversed these effects. These results suggest that TRPC6 may play a role in PASMCs proliferation and apoptosis under hypoxia and hypercapnia by regulating [Ca2+]i.

Research progress in physicochemical characteristics of lactoferrin and its recombinant expression systems.

Lactoferrin is an iron-binding glycoprotein with a molecular weight of about 80 kDa that belongs to the transferrin family. Due to its unique physical and chemical properties, lactoferrin has a variety of biological functions including antibacterial, antiviral, anticancer, immunomodulatory activities and regulation of iron absorption. High-yield production of recombinant lactoferrin with biological activity and its application in clinical treatment have been a hot topic for long time. With the development of genetic engineering techniques, various expression systems have been developed to produce recombinant lactoferrin. In this review, we summarize physicochemical characteristics, biological activities, clinical studies and current recombinant expression systems of lactoferrin, in order to provide references for its clinical application.

Association of pain with falls and fractures among middle-aged Korean community-dwelling adults.

The relationship between pain and falls remains controversial. Therefore, this study explored the associations between pain and fall-related outcomes in 5,340 middle-aged (45-65 years) adults residing in the communities in Korea. Pain was defined as pain at any location, pain-related activity restriction (PAR), and persistent pain. The outcome measures included fall injuries, recurrent falls, injurious falls, and fall-related hip fractures. A multivariate logistic regression model was used to examine the relationship between pain and fall outcome. Among the study participants, 54.0% reported having experienced pain. During a follow-up period of up to 14 years, those who reported pain and PAR at baseline exhibited a positive association with the occurrence of fall injury (odds ratio [OR] 1.79, 95% confidence interval [CI] 1.27-2.53) and injurious falls (OR 1.72, 95% CI 1.20-2.48) but not with recurrent falls (OR 1.90, 95% CI 0.80-4.54). We also observed a positive association between persistent pain and the risk of fall injury (OR 1.41, 95% CI 1.13-1.91), whereas no consistent conclusions were drawn regarding the risk of recurrent falls and injurious falls. We also did not identify any correlation between pain and hip fractures resulting from falls. In conclusion, our findings of the positive correlations of pain and PAR at baseline with fall injuries and injurious falls but not recurrent falls during follow-up suggest that public health initiatives should prioritize pain screening, especially for participants reporting ankle and toe pain, and implement suitable interventions to mitigate the risk of falls and the associated adverse outcomes among middle-aged adults.

The association between depressive symptoms with fear of falling and cognitive decline in older adults in the Korean community: An analysis of the Korean Longitudinal Study of Aging (KLoSA), 2006-2020.

OBJECTIVES: This study aimed to investigate the effects of fear of falling (FOF) on cognitive decline in older adults in the Korean community, depending on the presence of accompanying depressive symptoms. METHODS: A total of 6263 individuals were included in the final analysis. Based on their baseline evaluation results for depressive symptoms and FOF, the subjects were divided into four groups: "normal control" (NC, n = 3783), "depression only" (Dep-only, n = 291), "fear of falling only" (FOF-only, n = 1755), and "depression with fear of falling" (Dep-FOF, n = 434). Cognitive decline was defined as a loss of more than three points in the K-MMSE score in participants with at least two years of follow-up. We examined the association between FOF accompanied by depressive symptoms and cognitive decline using a multivariate Cox proportional hazard model. RESULTS: Cognitive decline occurred in 76.3%, 68.5%, 63.9%, and 56.4% of the Dep-FOF, FOF-only, Dep-only, and NC groups, respectively. Our findings suggest that individuals with FOF do not always have cognitive decline (HR = 1.03, 95% CI = 0.95-1.12, P = 0.43) compared to individuals without FOF. Furthermore, depressive symptoms with FOF are associated with a higher risk of cognitive decline (HR = 1.23, 95% CI = 1.08-1.41, P = 0.002) in community-dwelling older adults in Korea. CONCLUSION: Healthcare providers should be attentive to community-dwelling older adults who experience both depressive symptoms and FOF because our findings suggest that this unique combination increases the risk of cognitive decline.

[Effect of silencing lycB gene on the carotenoid synthesis in Haematococcus pluvialis].

Haematococcus pluvialis is a freshwater planktonic single-cell microalgae. It will accumulate high amount of carotenoids under unfavorable environmental conditions. As one of carotenoids, lycopene is an important intermediate in the carotenoid biosynthesis pathway. Lycopene ß-cyclase (LycB) is the key enzyme that catalyzes the circularization of lycopene to form ß-carotene. In this study, we constructed a p1301-BS-RNAi vector using lycB from Dunaliella salina as the interference sequence with kanamycin and atrazine resistance marker, and then transformed it into H. pluvialis by electroporation. Sixteen independent transgenic lines were obtained after resistance selection, genome PCR, and RT-PCR analyses. Seven well-grown lines were selected to determine the contents of carotenoids by HPLC analysis after inducing by high light. The lycopene content in these lines was increased by 99.4% while the ß-carotene content was decreased by 48.4%, indicating that the interference by heterogenous lycB could inhibit the conversion of lycopene into ß-carotene. The amount of increase in lycopene was only 5% of the amount of decrease in ß-carotene, indicating that 95% of the decreased ß-carotene was converted into other metabolites. Therefore, in order to largely increase the lycopene content in H. pluvialis, it is necessary to coordinatively regulate other metabolic pathways.

Effect of mean heart rate on 30-day mortality in ischemic stroke with atrial fibrillation: Data from the MIMIC-IV database.

Background: The relationship of mean heart rate (MHR) with 30-day mortality in ischemic stroke patients with atrial fibrillation in the intensive care unit (ICU) remains unknown. This study aimed to investigate the association between MHR within 24 h of admission to the ICU and 30-day mortality among patients with atrial fibrillation and ischemic stroke. Methods: This retrospective cohort study used data on US adults from the Medical Information Mart for Intensive Care-IV (MIMIC-IV, version 1.0) database. Patients with ischemic stroke who had atrial fibrillation for and first time in ICU admission were identified from the MIMIC-IV database. We used multivariable Cox regression models, a restricted cubic spline model, and a two-piecewise Cox regression model to show the effect of the MHR within 24 h of ICU admission on 30-day mortality. Results: A total of 1403 patients with ischemic stroke and atrial fibrillation (mean [SD] age, 75.9 [11.4] years; mean [SD] heart rate, 83.8[16.1] bpm; 743 [53.0%] females) were included. A total of 212 (15.1%) patients died within 30 days after ICU admission. When MHR was assessed in tertials according to the 25th and 50th percentiles, the risk of 30-day mortality was higher in participants in group 1 (< 72 bpm; adjusted hazard ratio, 1.23; 95% CI, 0.79-1.91) and group 3 (≥82 bpm; adjusted hazard ratio, 1.77; 95% CI, 1.23-2.57) compared with those in group 2 (72-82 bpm). Consistently in the threshold analysis, for every 1-bpm increase in MHR, there was a 2.4% increase in 30-day mortality (adjusted HR, 1.024; 95% CI, 1.01-1.039) in those with MHR above 80 bpm. Based on these results, there was a J-shaped association between MHR and 30-day mortality in ischemic stroke patients with atrial fibrillation admitted to the ICU, with an inflection point at 80 bpm of MHR. Conclusion: In this retrospective cohort study, MHR within 24 h of admission was associated with 30-day mortality (nonlinear, J-shaped association) in patients with ischemic stroke and atrial fibrillation in the ICU, with an inflection point at about 80 bpm and a minimal risk observed at 72 to 81 bpm of MHR. This association was worthy of further investigation. If further confirmed, this association may provide a theoretical basis for formulating the target strategy of heart rate therapy for these patients.

Design and Experimental Research of Implantable Lower Esophageal Sphincter Stimulator Based on Android Bluetooth.

The aim of this study is to design an implantable Lower Esophageal Sphincter (LES) stimulator connected and controlled by an Android Bluetooth for the treatment of the gastroesophageal reflux disease (GERD). Then the animal experiments are carried out to evaluate the function of the system. The LES stimulator is composed of an external controller, an Android application (APP) via a smart phone and an implantable electronic device (IED). The external controller is designed to receive the settings parameters information sent by the Android APP via a Bluetooth module, and then is programmed to generate specific electrical stimulation pulses to the LES. The Android APP controls the start and stop of stimulation and the settings of stimulation parameters. The in vivo IED consists of a bipolar stimulating lead, a bipolar head connector and a receiving module. The bipolar stimulating lead is constructed of biocompatible materials: platinum-iridium electrodes which are coated with parylene and an outer silicone rubber sheathing. The size of the receiving module has been significantly decreased to 20×20×2 mm3, which is packaged by polydimethylsiloxane (PDMS) and proposed to deliver stimulation pulses from the external controller to the implantable lead. The one-month implantation experiment on rabbits has been performed to evaluate the LES stimulator. The results indicate that the proposed LES stimulator meets the requirements of the functions, effectiveness and safety.

Nitrogen-doped micro-nano carbon spheres with multi-scale pore structure obtained from interpenetrating polymer networks for electrochemical capacitors.

A chemical process was developed to prepare N-doped micro-nano carbon spheres with multi-scale pore structures via carbonization of N-PF/PMMA interpenetrating polymer networks, which contain melamine resin as the nitrogen source, PF as the carbon source, and polymethylmethacrylate (PMMA) as the pore-former. The N-content of N-doped micro-nano carbon spheres was controlled by adjusting the mass ratio of melamine and phenol before polymerization. The N-doped micro-nano carbon spheres as electrode materials possess appropriate pore size distribution, higher specific surface area (559 m2 g-1) and consistently dispersed nitrogen atoms with adjustable doping content. These distinct characteristics endow the prospective electrode materials with excellent performance in electrochemical capacitors. In particular, N-CS-IPN-4 exhibits the highest specific capacitance of 364 F g-1 at 0.5 A g-1 in 6 M KOH aqueous electrolyte in a three-electrode system. It also possesses superior rate capability (57.7% retention at current densities ranging from 0.5 to 50 A g-1) and excellent cycling performance at 2 A g-1 (100% retention after 10 000 cycles). All these results confirm that the N-doped micro-nano carbon spheres are promising electrochemical capacitor materials, which possesses the advantages of simple preparation procedure, multi-scale pore structures, higher specific surface areas, easy adjustment of N-content and excellent electrochemical properties.

[The role of endoplasmic reticulum stress in pulmonary hypertension in rat induced by chronic hypoxia and hypercapnia].

OBJECTIVE: To observe the pulmonary vascular remodeling in rats with pulmonary hypertension induced by hypoxia and hypercapnia, and to explore the role of endoplasmic reticulum stress in pulmonary hypertension. METHODS: Forty SD rats were random-ly divided into four groups:normoxic control group (N), hypoxia hypercapnia group (HH), ERS inhibitor 4-phenylbutyric acid group (4-PBA), endoplasmic reticulum stress (ERS) pathway agonist tunicamycin group (TM), ten rats in each group.The mean pulmona-ry artery pressure (mPAP), mean carotid artery pressure (mCAP) and right ventricular hypertrophy index of rats in each group were measured.Pulmonary artery smooth muscle cells were identified by immunofluorescence α-smooth muscle actin (α-SMA).Morphologi-cal changes of lung tissue and pulmonary artery were observed by electron microscope.The apoptotic index of pulmonary artery smooth muscle cells in each group was detected by TUNEL.Reverse transcription polymerase chain reaction (RT-PCR) and Western blot were used to detect the expression of glucose-regulated protein (GRP78), C/EBP homologous protein (CHOP), c-Jun N-terminal kinase (JNK) and cysteinyl aspartate specific proteinase-12 (caspase-12) mRNA and protein in each group. RESULTS: ①Compared with the N group, the mPAP, the ratio of right ventricle weight to left ventricle plus ventricular septum weight[RV/(LV+S)]and the ratio of pulmonary artery wall area to total tube area (WA/TA) were increased (P<0.01), and the ratio of pulmonary artery luminal area to total tube area (LA/TA) were decreased (P<0.01), pulmonary artery smooth muscle cell apoptosis index were decreased (P<0.05 or P<0.01) in HH group, 4-PBA group and TM group.ERS related protein and mRNA expressions were increased, the differences were statistically significant.②Compared with the HH group, the mPAP, [RV/(LV+S)]and WA/TA of 4-PBA group were decreased (P <0.01), LA/TA and pulmonary artery smooth muscle cell apoptosis index were increased (P<0.01, P<0.05).The expressions of ERS related protein and mRNA were all decreased (P<0.05 or P<0.01).③Compared with the HH group, the mPAP, [RV/(LV+S)]and WA/TA of TM group were increased (P<0.05 or P<0.01), pulmonary artery middle layer thickened, LA/TA and pulmonary artery smooth muscle cell apoptotic index were decreased (P<0.01).ERS related protein and mRNA expressions were increased with statistical significance except GRP78 protein. CONCLUSIONS: Pulmonary vascular remodeling in rats with pulmonary hypertension induced by hypoxia and hypercapnia may be related to the excessive proliferation of pulmonary artery smooth muscle cells and too little apopto-sis;ERS related factors (JNK, caspase-12 and CHOP) are involved in the regulation of pulmonary hypertension induced by hypoxia hypercapnia.

Decreased fragile histidine triad expression in colorectal cancer and its association with apoptosis inhibition.

AIM: To detect the expression of fragile histidine triad (FHIT) in normal colorectal tissue, colorectal adenoma and colorectal cancer (CRC) tissue, and to analyze its relationship with the clinicopathological features of CRC, and apoptosis-associated proteins (Bcl-2, Bax, survivin) and apoptosis in colorectal cancer. METHODS: FHIT mRNA analysis was performed by nested reverse transcription-polymerase chain reaction (RT-PCR) assay. Tissue microarray (TMA) was established to detect the expression of FHIT, Bcl-2, Bax and survivin genes in 80 CRC tissue specimens, 16 colorectal adenoma tissue specimens and 16 hemorrhoid (PPH) tissue specimens during the same period of time as the control. Citrate-microwave-SP was used as immunohistochemical method. The relationship between clinicopathological factors, such as differentiation grades and 5-year survival rate was observed. TUNEL assay was used to detect the apoptosis index in 80 CRC tissue specimens. RESULTS: Ten out of 26 (38.5%) CRC tissue specimens expressed aberrant FHIT transcripts, none of the aberrant FHIT transcripts was observed in the matched normal tissue and colorectal adenoma tissue by nested RT-PCR assay. The positive rate of FHIT gene expression in normal colorectal tissue, colorectal adenoma and carcinoma tissue was 93.75%, 68.75% and 46.25%, respectively. Clinicopathological analysis of patients showed that the decreased FHIT gene expression was not associated with age, sex, serum CEA levels, tumor site and size, histological classification. However, the expression of FHIT was correlated with differentiation grades, pathological stages, lymph node metastases and 5-year survival rate after operation. The positive rate of apoptosis-associated proteins (Bax, Bcl-2 and survivin) in CRC tissue was 72.50%, 51.25% and 77.50%, respectively. The expression of these apoptosis-associated proteins in CRC tissue was correlated with the expression of FHIT. The mean apoptosis index in FHIT negative tumors was significantly lower than that in FHIT positive tumors (5.41 +/- 0.23 vs 0.56 +/- 0.10, P < 0.01). CONCLUSION: The FHIT gene plays an important role in the regulation of apoptosis and decreased FHIT expression plays a key role in the initiation and progression of colorectal carcinoma.

[The regulation of MAPK signaling pathway on cell proliferation and apoptosis in hypoxic PASMCs of rats].

OBJECTIVE: To explore the relationship between hypoxic pulmonary arterial smooth muscle cells(PASMCs)proliferation, apop-tosis and mitogen-activated protein kinases(MAPK) signal pathway in rats. METHODS: PASMCs were obtained from male SD rats by the enzyme digestion method and primarily cultured; PASMCs were identified through two methods:immunofluorescence staining and light microscopy; the 4~6th generation PASMCs of logarithmic growth state of good growth period were selected, and randomly divided into 7 groups:normoxic con-trol group (N), hypoxia group (H), DMSO group (D), extracellular signal-regulated kinase1/2(ERK1/2) inhibitor-U0126 group (U) and p38MAPK inhibitor-SB203580 group (S), the p38MAPK activator-Anisomycin group (A), the ERK1/2 activator-Staurosporine Aglycone group (SA). When all the models were completed, the all groups joined the CCK-8 to measure cell proliferation; cell apoptosis of each group was detected by TUNEL kit after the modeling. RESULTS: Compared with N group, the expression of OD value in H group was up-regulated (0.990 ±0.041 vs 1.143 ±0.033,P < 0.01). There was no statistical significance on PASMCs apoptosis index(AI) in H group (4.913 ±0.451 vs 5.452 ±0.557, P > 0.05); Compared With H group, there were no statistical significance on the expression of PASMCs OD value and apoptosis index(AI)in D group (1.143 ±0.033 vs 1.142 ±0.049,5.452 ±0.557 vs 5.402 ±0.651,P > 0.05); the expression of OD value in U group was down-regulated, and the expression of AI was up-regulated (1.143 ±0.033 vs 0.985 ±0.078, 5.452 ±0.557 vs 10.145 ±2.545, P < 0.01); the expression of OD value in S group was up-regulated, and the expression of AI was down-regulated (1.143 ±0.033 vs 1.295 ±0.039, 5.452 ±0.557 vs 3.093 ±0.409, P < 0.01); the expression of OD value in A group was down-regulated, and the expres-sion of AI was up-regulated (1.143 ±0.033 vs 0.347 ±0.067, 5.452 ±0.557 vs 25.753 ±1.262, P < 0.01); the expression of OD value in SA group was up-regulated, and the expression of AI was down-regulated (1.143 ±0.033 vs 1.685 ±0.100, 5.452 ±0.557 vs 1.700 ±0.095, P < 0.01). CONCLUSIONS: The regulation of PASMCs' proliferation and apoptosis under hypoxia condition have a relationship with the participation of MAPK signal pathway.

[Expression of glutathione S-transferase zeta class genes in Saccharomyces cerevisiae].

The zeta class of glutathione S-transferase (GSTZs), which is an important multifunctional enzyme, relates to the cell metabolism and contamination elimination. The GSTZ genes from Arabidopsis thaliana L. and Brassica napus L. cv. Shan 2B and Ken C1 were cloned into the multi-cloning site of the shuttle expression vector pYES2. After the recombinants were obtained, the recombinant plasmids were isolated and introduced into the defective mutant INCSc1 of Saccharomyces cerevisiae. Then the recombinant strains Y2At, Y2BnB and Y2BnC were obtained after cultured on SC-U selective plates. When induced in the medium containing galactose and maltose, the recombinant yeast expressed as active GSTZs showing the dichloroacetic acid dechlorinating activity, which existed in the yeast cell as a soluble state. The comparison of different carbon sources showed that sucrose and glucose significantly exhibited the expression of GSTZ gene; glycerol somewhat affected the growth of yeast but increased the specific activity of GSTZ by 17%; and galactose slightly affected the yeast growth with no affection to the activity of GSTZ. Zero to ninety-six hrs induction experiments showed that specific activity of GSTZ in recombinant yeast reached highest when induced for 36 hours. The specific activity of AtGSTZ, BnGSTZ-B and BnGSTZ-C was 5.3 U/mg, 4.3 U/mg and 0.3 U/mg, respectively. The values are lower than that expressed in the E. coli and wheat-sperm cell-free protein synthesis system. However, the relative activity of three sources was similar in E. coli and wheat cell free system. The Km value of GSTZ genes from different sources was 0.59 mmol/L and 0.79 mmol/L for AtGSTZ and BnGSTZ-B, respectively, suggesting the GSTZ enzyme from Abrabidopsis thaliana has higher affinity to DCA than that from Brassica napus.

[Characteristics of SRAP marker in detecting polymorphism of cucumber genome].

When SRAP (Sequence-Related Amplified Polymorphism) marker was used in constructing genetic map and analyzing QTL for high temperature resistance in cucumber (Cucumis sativus L.), it exhibited certain characteristics in detecting genomic polymorphism. When each forward primer was combined with different reverse primers, the number of primer combinations that produced polymorphism ranged from five to eight. When each reverse primer was in combination with different forward primers, the number of polymorphic primer combinations ranged from two to eleven. The reverse primers SA4 or EM6 produced identical polymorphic bands when combined with all the forward primers tested. These bands might be amplified by the reverse primers. The polymorphic bands amplified from OD3ME11 co-segregated in the F2 population. The utilization of these characteristics in our research was discussed.

[Effects of xuebijing injection on cardiac function and structure in rats with myocardial hypoxia/reoxygenation injury].

OBJECTIVE: To investigate the protective effects of xuebijing (XBJ, Traditional Chinese Medicine Complex) injection on cardiac function in rats with myocardial hypoxia/reoxygenation(H/R) injury. METHODS: The isolated langendorff perfused rat heart model was established. One hundred and thirty SD rats were randomly divided into sham group, hypoxia/reoxygenation group, low dose XBJ(XBJL) group, middle dose XBJ(XBJM) group and high dose XBJ(XBJH) group. All groups except sham group were divided into three subgroups according to reoxygenation time(0.5 h,1 h, 2 h) (n=10). In sham group, left ventricular development pressure(LVDP), maximal rates of increase/decrease of the left ventricular pressure(±dp/dtmax), left ventricular pressure (LVP), and heart rates (HR) were recorded after 20 minutes balance perfusion. The creatine kinase-MB (CK-MB) in myocardium was detected by ELISA. In other groups, after 20 minutes balance perfusion, we perfused ThomasⅡto stop the hearts from beating for 30 minutes, then reperfused the K-H until hearts recover beating. The microstructure of myocardium was observed under light microscopy. LVDP, ±dp/dtmax, LVP and HR were continuously recorded in other four groups and the concentrations of CK-MB in myocardium were measured by ELISA at different time points after reoxygenation. Microstructure of myocardium in each group were observed under light microscopy. RESULTS: LVDP, ±dp/dtmax, LVP and HR of other groups were significantly lower than those of sham group(P<0.05). The levels of CK-MB were higher than that of sham group(P<0.05). LVDP, ±dp/dtmax, LVP and HR of XBJL, XBJM and XBJH groups were higher than those of I/R group at corresponding time points after reoxygenation(P<0.05). The levels of CK-MB were lower than that of I/R group(P<0.05) and the cardiac function was improved. The middle dose of XBJ had the best protective effect. CONCLUSIONS: Xuebijing injection can effectively improve cardiac function and structure in rats with myocardial hypoxia/reoxygenation injury, and middle dose of XBJ is the best.

[DNA damage, Bcl-2, Bax expression and ultrastructure change in spermatogenic cell of mice exposed to cadmium].

OBJECTIVE: To study DNA damage, Bcl-2 and Bax expression, and ultrastructure change in spermatogenic cell of mice by cadmium exposure. METHODS: Twenty-four male mice were divided into 4 groups: 3 groups treated with cadmium chloride of 1, 5, 10 micromol x kg(-1) x d(-1) i.p. respectively for 5 days, and one normal saline control group. The DNA damage of spermatogenic cell by single-cell gel electrophoresis technology was detected. The expression positive rate of Bcl-2, Bax protein in spermatogenic cell by the immunohistochemical method was assayed, and the ultrastructural change of spermatogenic cell by the transmission electron microscope was observed. RESULTS: DNA damage rates of of spermatogenic cell in 1, 5, 10 micromol/kg cadmium chloride groups were higher than that of normal group (P < 0.001). Bcl-2 protein expression positive rates were lower than that of normal group (P < 0.001). Bax protein positive expression rate in 5 micromol/kg group was higher than those in normal group, and 1, 10 micromol/kg groups. The ultrastructure of karyotis, karyotheca, mitochondria, endoplasmic reticulum in three treated groups had different degree of damage and the degree of ultrastructural change was increasing with rising concentration of cadmium. CONCLUSION: Cadmium exposure will cause the DNA break, Bcl-2 and Bax protein abnormal expression and ultrastructural change in spermatogenic cell.

DNA Marker Transmission and Linkage Analysis in Populations Derived from a Sugarcane (Saccharum spp.) x Erianthus arundinaceus Hybrid.

Introgression of Erianthus arundinaceus has been the focus of several sugarcane breeding programs in the world, because the species has desirable traits such as high biomass production, vigour, ratooning ability and good resistance to environmental stresses and disease. In this study four genetic maps were constructed for two intergeneric populations. The first population (BC1) was generated from a cross between an Erianthus/Saccharum hybrid YC96-40 and a commercial sugarcane variety CP84-1198. The second population (BC2) was generated from a cross between YCE01-116, a progeny of the BC1 cross and NJ57-416, a commercial sugarcane cultivar. Markers across both populations were generated using 35 AFLP and 23 SSR primer pairs. A total of 756 and 728 polymorphic markers were scored in the BC1 and BC2 populations, respectively. In the BC1 population, a higher proportion of markers was derived from the Erianthus ancestor than those from the Saccharum ancestor Badila. In the BC2 population, both the number and proportion of markers derived from Erianthus were approximately half of those in the BC1 population. Linkage analysis led to the construction of 38, 57, 36 and 47 linkage groups (LGs) for YC96-40, CP84-1198, YCE01-116, and NJ57-416, encompassing 116, 174, 97 and 159 markers (including single dose, double dose and bi-parental markers), respectively. These LGs could be further placed into four, five, five and six homology groups (HGs), respectively, based on information from multi-allelic SSR markers and repulsion phase linkages detected between LGs. Analysis of repulsion phase linkage indicated that Erianthus behaved like a true autopolyploid.