Electroacupuncture for urinary retention after stroke: A systematic review and meta-analysis of randomized controlled trials.

BACKGROUND AND PURPOSE: Electroacupuncture (EA) is one of the non-pharmacological therapies in traditional Chinese medicine to treat urinary retention. The objective of this meta-analysis is to assess the efficacy of electroacupuncture in the treatment of urinary retention after stroke. METHODS: Overall, seven electronic databases were searched until December 31, 2023, and randomized control trials about EA for urinary retention after stroke were reviewed. Two reviewers independently screened the literature, extracted the data, and assessed the risk of bias for included studies. The meta-analysis was conducted by RevMan 5.4 and Stata/MP 17.0 software. RESULTS: Eleven studies with a total of 856 participants were included in this meta-analysis. EA treatment yielded an improved reduction in the post-void residual (PVR) (mean difference [MD]: 37.85, 95 % confidence interval [CI]: 55.09 to -20.61 p < 0.0001) and the weight of diaper pads (MD: 38.87, 95 % CI: 42.68 to -335.06). Further analysis indicated that EA improved the effectiveness ratio (risk ratio [RR]: 1.36, 95 % CI: 1.20 to 1.53, p < 0.00001), the function of the bladder (MD: 0.45, 95 % CI: 0.61 to -0.30), and the quality of life (MD: 1.15, 95 %: CI: 2.10 to -0.20) in comparison to normal treatment and simple acupuncture. CONCLUSION: EA may be an effective way and reasonable modality to incorporate into the multiple prevention and therapy for urinary retention after stroke. The wide application of EA could be associated with the improvement of bladder and life quality and decline in the PVR for patients after stroke with urinary retention.

Strain-Specific Benefits of Bacillus Probiotics in Hybrid Grouper: Growth Enhancement, Metabolic Health, Immune Modulation, and Vibrio harveyi Resistance.

In the realm of modern aquaculture, the utilization of probiotics has gained prominence, primarily due to their ability to enhance growth, boost immunity, and prevent diseases in aquatic species. This study primarily investigates the efficacy of Bacillus subtilis strains, both host-derived and from other sources, in influencing fish growth, immunity, lipid metabolism, and disease resistance. Employing a 42-day feeding trial, we divided hybrid grouper into four distinct groups: a control group on a basal diet and three experimental groups supplemented with 1 × 108 CFU/g of different Bacillus subtilis strains-BS, 6-3-1, and HAINUP40. Remarkably, the study demonstrated that the 6-3-1 and HAINUP40 groups exhibited significant enhancements across key growth parameters: final body weight (FBW), weight gain rate (WGR), feed intake (FI), feed efficiency ratio (FER), and feed conversion ratio (FCR). The investigation into lipid metabolism revealed that the 6-3-1 strain upregulated seven metabolism-related genes, HAINUP40 affected four metabolism-related genes, and the BS strain influenced two metabolism-related genes, indicating diverse metabolic impacts by different strains. Further, a notable reduction in liver enzymes AST and ALT was observed across all supplemented groups, implying improved liver health. Noteworthy was the BS strain's superior antioxidative capabilities, positively affecting all four measured parameters (CAT, GSH-Px, MDA). In the sphere of immune-related gene expression, the BS strain significantly decreased the expression of both inflammation and apoptosis-related genes, whereas the HAINUP40 strain demonstrated an upregulation in these genes. The challenge test results were particularly telling, showcasing improved survival rates against Vibrio harveyi infection in the BS and 6-3-1 groups, unlike the HAINUP40 group. These outcomes highlight the strain-specific nature of probiotics and their varying mechanisms of action within the host. In conclusion, this study reveals that probiotic strains, varying by source, demonstrate unique, strain-specific effects in promoting growth and modulating immunity in hybrid grouper. This research highlights the promise of tailored probiotic applications in improving aquaculture practices. Such advancements contribute to more sustainable and efficient fish farming methods.

Electroacupuncture Promotes Angiogenesis in Mice with Cerebral Ischemia by Inhibiting miR-7.

OBJECTIVE: To observe the angiogenesis effect of electroacupuncture (EA) at Shuigou acupoint (GV 26) in the treatment of cerebral ischemia, and explore the value of miRNA-7 (miR-7) in it. METHODS: First, 48 mice were randomly divided into sham operation, middle cerebral artery occlusion (MCAO) model, and EA treatment groups. Then 9 mice were divided into carrier control group, miR-7 knockout group and miR-7 overexpression group (n=3 each group). Finally, 20 mice were divided into model and carrier control group, model and miR-7 knockout group, EA treatment and carrier control group and EA treatment and miR-7 overexpression group, with 3-6 mice in each group. The MCAO model was established in the MCAO and EA groups. Neurological deficit score and 2,3,5-triphenyltetrazolium chloride (TTC) staining were used to evaluate the severity of cerebral ischemia. Hematoxylin-eosin staining was used to describe basic pathological changes. Immunohistochemistry was used to quantify cerebral microvessel density. Real-time PCR and Western blot were used to detect the expression of miR-7 and its downstream target genes Krüppel-like factor 4/vascular endothelial growth factor (KLF4/VEGF) and angiopoietin-2 (ANG-2) in the ischemic cerebral cortex. RESULTS: After EA, neurological deficit scores and infarction volumes decreased, and the density of cerebral microvessels increased. In the MCAO group, miR-7 expression was higher than that in the sham group (P<0.01). After EA at GV 26, miR-7 expression decreased (P<0.01) and the expression of downstream target genes KLF4/VEGF and ANG-2 increased as compared with the MCAO group (P<0.01). After EA combined with overexpression of miR-7, the expression of downstream target genes KLF4/VEGF and ANG-2 decreased compared to the control EA group (P<0.01). After miR-7 knockdown, the expression of KLF4/VEGF and ANG-2 increased (P<0.05 or P<0.01). CONCLUSIONS: EA could promote angiogenesis in MCAO mice likely by inhibiting the expression of miR-7 and relieving inhibition of downstream target genes KLF4/VEGF and ANG-2.

Research progress and prospects on gas-sensitive mechanisms of semiconductor sensors.

Semiconductor materials with wide bandgaps are extensively employed for gas detection due to their advantages of low cost, high sensitivity, fast speed, excellent stability, and distinctive selectivity. Previous studies have reported on different kinds of semiconductor materials and their complex synthesis procedures. However, the research progress on gas-sensitive mechanisms seriously lags behind the performance improvement. The research route of the gas-sensing mechanism is not clear, resulting in an unclear development direction of novel sensitive materials. This review aims to summarize existing approaches and their progress on the interpretation of gas-sensing mechanisms in semiconductors, such as the calculations based on density functional theory, semiconductor physics, and in situ experiments. Ultimately, a reasonable route for the mechanism investigation has been proposed. It guides the development direction of novel materials and reduces the cost of screening highly selective materials. Overall, this review can provide helpful guidance concerning the gas-sensitive mechanism for scholars.

Thionine-functionalized three-dimensional carbon nanomaterial-based aptasensor for analysis of Aß oligomers in serum.

How to sensitively detect early biomarkers of Alzheimer's disease (AD) is nowadays, one of the major challenges. In this work, Aß oligomers (AßO), one of the AD biomarkers, was analyzed using an electrochemical aptasensor, which was prepared based on thionine (Th) - functionalized three - dimensional carbon nanomaterials (reduced graphene oxide (rGO) and multi-wall carbon nanotubes (MWCNTs)) immobilized DNA-aptamer. Th, a positively charged planar aromatic molecule, form many π - π conjugated structures with rGO and MWCNTs, then improving the structural stability, electron transfer and the capacitive properties of Th-rGO-MWCNTs nanocomposites. Under the optimal conditions, differential pulse voltammetry (DPV) current responses decreased with the increase of AßO concentration. The obtained AßO aptasensor presented a wide linear range of 0.0443 pM-443.00 pM and limit of detection (LOD) was 10 fM. Meanwhile, AßO aptasensor displayed remarkable stability and selectivity. It has a great potential for early diagnosis of AD in human real serum samples.

The role of STAT3/p53 and PI3K-Akt-mTOR signaling pathway on DEHP-induced reproductive toxicity in pubertal male rat.

Di (2-ethylhexyl) phthalate (DEHP) is a known environmental endocrine disruptor that impairs development of testis and spermatogenesis. This study aims to explore the effects of STAT3/p53 and PI3K-Akt-mTOR signaling pathway on DEHP-induced reproductive toxicity in pubertal male rat. 24 6-week-old male Sprague-Dawley rats were randomly divided into 4 groups (Control, low-dose, middle-dose and high-dose group) and were treated with increasing concentration of DEHP (0, 250, 500, 1000 mg/kg/day) respectively for 28 consecutive days by intragastric administration. Our results showed that DEHP exposure induced obvious morphological changes of testis, decreased organ coefficient of testis and sperm count, and increased testicular cell apoptosis in the 500 and 1000 mg/kg/day DEHP groups (p < .05). The serum testosterone decreased in a dose-dependent manner after treatment with DEHP. Furthermore, the exposure of DEHP elevated the levels of oxidative stress accompanied by upregulated expression of p53 and reduced expression of STAT3. In addition, compared with the control group, the expression of PI3K, p-Akt and p-mTOR proteins significantly decreased, whereas the downstream autophagy-related proteins phosphorylated ULK1, Beclin-1, Atg7, LC3-II obviously increased in the 250 mg/kg/day DEHP group (p < .05). The expression of p62 was reduced in DEHP-treated groups. Our data indicated that autophagy could be activated to protect testes from DEHP-induced reproductive damage by inhibiting PI3K-Akt-mTOR signaling pathway in the 250 mg/kg/day DEHP group. STAT3/p53-mediated mitochondrial apoptosis pathway might play a major role to cause testis injury and reproductive dysfunction in the 500 and 1000 mg/kg/day DEHP groups.

COP9 signalosome complex subunit 5, an IFT20 binding partner, is essential to maintain male germ cell survival and acrosome biogenesis†.

Intraflagellar transport protein 20 (IFT20) is essential for spermatogenesis in mice. We discovered that COPS5 was a major binding partner of IFT20. COPS5 is the fifth component of the constitutive photomorphogenic-9 signalosome (COP9), which is involved in protein ubiquitination and degradation. COPS5 is highly abundant in mouse testis. Mice deficiency in COPS5 specifically in male germ cells showed dramatically reduced sperm numbers and were infertile. Testis weight was about one third compared to control adult mice, and germ cells underwent significant apoptosis at a premeiotic stage. Testicular poly (ADP-ribose) polymerase-1, a protein that helps cells to maintain viability, was dramatically decreased, and Caspase-3, a critical executioner of apoptosis, was increased in the mutant mice. Expression level of FANK1, a known COPS5 binding partner, and a key germ cell apoptosis regulator was also reduced. An acrosome marker, lectin PNA, was nearly absent in the few surviving spermatids, and expression level of sperm acrosome associated 1, another acrosomal component was significantly reduced. IFT20 expression level was significantly reduced in the Cops5 knockout mice, and it was no longer present in the acrosome, but remained in the Golgi apparatus of spermatocytes. In the conditional Ift20 mutant mice, COPS5 localization and testicular expression levels were not changed. COP9 has been shown to be involved in multiple signal pathways, particularly functioning as a co-factor for protein ubiquitination. COPS5 is believed to maintain normal spermatogenesis through multiple mechanisms, including maintaining male germ cell survival and acrosome biogenesis, possibly by modulating protein ubiquitination.

Mouse spermatogenesis-associated protein 1 (SPATA1), an IFT20 binding partner, is an acrosomal protein.

BACKGROUND: Intraflagellar transport is a motor-driven trafficking system that is required for the formation of cilia. Intraflagellar transport protein 20 (IFT20) is a master regulator for the control of spermatogenesis and male fertility in mice. However, the mechanism of how IFT20 regulates spermatogenesis is unknown. RESULTS: Spermatogenesis associated 1 (SPATA1) was identified to be a major potential binding partner of IFT20 by a yeast two-hybrid screening. The interaction between SPATA1 and IFT20 was examined by direct yeast two-hybrid, co-localization, and co-immunoprecipitation assays. SPATA1 is highly abundant in the mouse testis, and is also expressed in the heart and kidney. During the first wave of spermatogenesis, SPATA1 is detectable at postnatal day 24 and its expression is increased at day 30 and 35. Immunofluorescence staining of mouse testis sections and epididymal sperm demonstrated that SPATA1 is localized mainly in the acrosome of developing spermatids but not in epididymal sperm. IFT20 is also present in the acrosome area of round spermatids. In conditional Ift20 knockout mice, testicular expression level and acrosomal localization of SPATA1 are not changed. CONCLUSIONS: SPATA1 is an IFT20 binding protein and may provide a docking site for IFT20 complex binding to the acrosome area.

Development of a Label-Free Electrochemical Aptasensor for the Detection of Tau381 and its Preliminary Application in AD and Non-AD Patients' Sera.

The electrochemical aptamer sensor has been designed for detecting tau381, a critical biomarker of Alzheimer's disease in human serum. The aptasensor is obtained by immobilizing the aptamer on a carboxyl graphene/thionin/gold nanoparticle modified glassy-carbon electrode. As a probe and bridge molecule, thionin connected carboxyl graphene and gold nanoparticles, and gave the electrical signal. Under optimal conditions, the increment of differential pulse voltammetry signal increased linearly with the logarithm of tau381 concentration in the range from 1.0 pM to 100 pM, and limit of detection was 0.70 pM. The aptasensor reliability was evaluated by determining its selectivity, reproducibility, stability, detection limit, and recovery. Performance analysis of the tau381 aptasensor in 10 patients' serum samples showed that the aptasensor could screen patients with and without Alzheimer's disease. The proposed aptasensor has potential for use in clinically diagnosing Alzheimer's disease in the early stage.

The sperm-associated antigen 6 interactome and its role in spermatogenesis.

Mammalian SPAG6, the orthologue of Chlamydomonas reinhardtii PF16, is a component of the central apparatus of the '9 + 2' axoneme that controls ciliary/flagellar motility, including sperm motility. Recent studies revealed that SPAG6 has functions beyond its role in the central apparatus. Hence, we reexamined the role of SPAG6 in male fertility. In wild-type mice, SPAG6 was present in cytoplasmic vesicles in spermatocytes, the acrosome of round and elongating spermatids and the manchette of elongating spermatids. Spag6-deficient testes showed abnormal spermatogenesis, with abnormalities in male germ cell morphology consistent with the multi-compartment pattern of SPAG6 localization. The armadillo repeat domain of mouse SPAG6 was used as a bait in a yeast two-hybrid screen, and several proteins with diverse functions appeared multiple times, including Snapin, SPINK2 and COPS5. Snapin has a similar localization to SPAG6 in male germ cells, and SPINK2, a key protein in acrosome biogenesis, was dramatically reduced in Spag6-deficient mice which have defective acrosomes. SPAG16L, another SPAG6-binding partner, lost its localization to the manchette in Spag6-deficient mice. Our findings demonstrate that SPAG6 is a multi-functional protein that not only regulates sperm motility, but also plays roles in spermatogenesis in multiple cellular compartments involving multiple protein partners.

Di(2-ethylhexyl) phthalate induces apoptosis through mitochondrial pathway in GC-2spd cells.

Di(2-ethylhexyl) phthalate (DEHP), a plasticizer of synthetic polymers, is a well-known endocrine disrupting chemical (EDC) and reproductive toxicant. Addressing the unclear mechanism of DEHP-induced reproductive dysfunction, this study used GC-2spd cells to investigate the molecular mechanism involved in the DEHP-induced toxicity in the male reproductive system. The results indicated that the apoptotic cell death was significantly induced by DEHP exposure over 100 µM. Furthermore, DEHP treatment could induce oxidative stress in GC-2spd cells involving in the decrease of superoxide dismutase (SOD) activity (200 µM) and glutathione peroxidase (GSH-Px) activity (50 and 100 µM). In addition, DEHP induction also caused the elevated ratios of Bax/Bcl-2, release of cytochrome c and decomposition of procaspase-3 and procaspase-9 in GC-2spd cells. Taken together, our work provided the evidence that DEHP exposure might induce apoptosis of GC-2spd cells via mitochondria pathway mediated by oxidative stress. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 1055-1064, 2017.

Characterization of membrane occupation and recognition nexus repeat containing 3, meiosis expressed gene 1 binding partner, in mouse male germ cells.

Mammalian spermatogenesis is a well-organized process of cell development and differentiation. Meiosis expressed gene 1 (MEIG1) plays an essential role in the regulation of spermiogenesis. To explore potential mechanisms of MEIG1's action, a yeast two-hybrid screen was conducted, and several potential binding partners were identified; one of them was membrane occupation and recognition nexus repeat containing 3 (MORN3). MORN3 mRNA is only abundant in mouse testis. In the testis, Morn3 mRNA is highly expressed in the spermiogenesis stage. Specific anti-MORN3 polyclonal antibody was generated against N-terminus of the full-length MORN3 protein, and MORN3 expression and localization was examined in vitro and in vivo. In transfected Chinese hamster ovary cells, the antibody specifically crossed-reacted the full-length MORN3 protein, and immunofluorescence staining revealed that MORN3 was localized throughout the cytoplasm. Among multiple mouse tissues, about 25 kDa protein, was identified only in the testis. The protein was highly expressed after day 20 of birth. Immunofluorescence staining on mixed testicular cells isolated from adult wild-type mice demonstrated that MORN3 was expressed in the acrosome in germ cells throughout spermiogenesis. The protein was also present in the manchette of elongating spermatids. The total MORN3 expression and acrosome localization were not changed in the Meig 1-deficient mice. However, its expression in manchette was dramatically reduced in the mutant mice. Our studies suggest that MORN3 is another regulator for spermatogenesis, probably together with MEIG1.

Urinary S-phenylmercapturic acid as a key biomarker for measuring occupational exposure to low concentrations of benzene in Chinese workers: a pilot study.

OBJECTIVE: This study analyzed the level of urinary S-phenylmercapturic acid (U-SPMA) for low benzene exposure in a group of Chinese shoe-making workers. METHODS: Urinary samples from 55 workers exposed to benzene at levels lower than 10 parts per million (ppm) were collected at postshift. U-SPMA level was determined using high-performance liquid chromatography/mass spectrography (HPLC/MS) method. RESULTS: Good linearity of U-SPMA was observed within the range from 10 to 320 µg/L (r = 0.9994). Concentration of airborne benzene ranged from 0.71 to 32.17 mg/m³, and three segments were divided with different levels of exposure (≤6.0, 6.0 to 10.0, 10 to 32.5 mg/m³), the median U-SPMA concentrations were 49.55, 102.15, and 335.69 µg/g Cr, respectively. CONCLUSION: A good linear correlation was found between U-SPMA levels and airborne benzene concentrations. The selected method could be applied for detecting other working conditions in China.

[Construction of a recombinant plasmid of BC022687 and identification of its expression and localization in CHO cells].

OBJECTIVE: To construct a mammalian expression plasmid of the BC022687 gene and investigate the expression and localization of the fusion protein in Chinese hamster ovary (CHO) cells. METHODS: The BC022687 coding sequence was amplified by polymerase chain reaction (PCR) and subcloned into the pEGFP-C1 vector carrying the gene of green fluorescence protein (GFP). After the target region was sequenced, the recombinant plasmid was transfected into CHO cells, and its expression in the CHO cells was determined by Western blot. The localization of GFP-tagged BC022687 in the CHO cells was observed by laser scanning confocal microscopy. RESULTS: BC022687 was successfully cloned into the mammalian expression vector pEGFP-C1, with the restriction fragment length of 950 bp. The expression of the fusion protein was confirmed, with the relative molecular weight of 64 000. The GFP-tagged BC022687 protein was mainly localized in the cytoplasm, and also presented in the centrioles in the transfected CHO cells. CONCLUSION: The successful construction of the plasmid expressing BC022687 in CHO cells has laid a foundation for further studies on the role of this protein in ciliogenesis.

[A cross-sectional study about the effects of residential exposure to power transmission line on human nervous system symptoms and hematology].

OBJECTIVE: To investigate the possible effects on nervous system and health condition under the exposure to electromagnetic field. METHODS: Take the resident around the power transmission line as the objects and were divided into 3 groups by the distance from the power transmission line 20 m, 100 m and 500 m, respectively. Some living conditions and health conditions were recorded by face-to-face the questionnaire survey, and Hematological indices of each groups were examined including IgG, IgM, leukocyte formulae, erythrocyte, hemoglobin and platelet. RESULTS: There was no significant difference in each group, according exposure of daily life, such as drinking and smoking (P > 0.05). Compared with the each distance groups, it was presented significant difference between the distance from the power transmission line and the incidence of headache or dizziness, insomnia and easy weary and so on (P < 0.05). In hematology aspect, with the horizontal distance from the power transmission line decreasing, PLT level of residents was reductive and the difference was statistically significant (P < 0.001), whereas leukocyte formulae, erythrocyte, hemoglobin, IgG and IgM had no significant difference among each group (P < 0.05). CONCLUSION: Closely exposure to electromagnetic field may induce headache and so on and decrease the level of PLT.

Trans, trans-muconic acid as a biomarker of occupational exposure to high-level benzene in China.

OBJECTIVE: The work aimed to study the potential correlation between the high-level benzene exposure and its urinary metabolites S-phenylmercapturic acid (SPMA) and trans, trans-muconic acid (t,t-MA) in Chinese shoe-making workers. METHODS: Individual benzene-exposed levels were determined by gas chromatography analysis, urinary t,t-MA, and urinary SPMA were determined by high performance liquid chromatography-an ultraviolet detector and liquid chromatography/electrospray tandem mass spectrometry method, respectively. RESULTS: The concentration of benzene ranged from 2.57 to 146.11 mg/m³. And the correlation between benzene and t,t-MA was significantly higher than that of SPMA at the postshift, for example, the correlation coefficient was 0.905 and 0.537 for t,t-MA and SPMA, respectively. Moreover, The relative internal exposure index of t,t-MA (0.28 mg/g Cr: mg/m³) was more similar to the data supplied by American Conference of Governmental Industrial Hygienists compared to the index of SPMA (0.025 mg/g Cr:mg/m³). CONCLUSIONS: t,t-MA appeared to be a more specific biomarker than SPMA at high-level benzene exposure.

[Determination of S-phenylmercapturic acid in human urine by HPLC-MS].

OBJECTIVE: To establish the method to determine S-phenylmercapturic acid (S-PMA) in human urine, and the method was actually applied to determine S-PMA concentrations in the human urine from subjects occupationally exposed to benzene. METHODS: After the urine samples are hydrolyzed by acidification, and modulated to suitable pH value. S-PMA is obtained by liquid-liquid extraction and separated by HPLC. Use negative ion mode electric spray ion source MS to measure, and select the molecular ion peak m/z 238 and quantitative analysis is performed by peak area. RESULTS: This method has good linear in the range of 5-320 microg/L, and r = 0.9994 +/- 0.0003, and the detection limit is 1.2 microg/L (S/N = 3), recovery percentage is 86.8%-94.2%. Both the intra- and inter-day precisions are less than 7%. Use this method to measure the S-PMA in the end-of-shift urine of 55 workers occupationally exposed to benzene and perform the regression analysis for the S-PMA concentration and the benzene concentration in air (r = 0.8035, P < 0.05). CONCLUSION: The method established by this research is rapid, sensitive and selective, and the results are accurate and reliable.

Biphasic effect of cadmium on cell proliferation in human embryo lung fibroblast cells and its molecular mechanism.

Hormesis, a biphasic dose-response phenomenon, is characterized by a low-dose stimulation and a high-dose inhibition. However, the mechanisms underlying hormesis induced by environmental agents are not well elucidated. The present study was to investigate the relationship between the hormesis effect of cadmium (Cd) and activation of ERK1/2, JNK and p38 pathways in human embryo lung fibroblast cells. Results showed that Cd induced significant cell proliferation at low concentrations, but markedly inhibited cell growth at high concentrations. Our data indicated that cell proliferation promoted by low concentrations of Cd was blocked obviously by ERK1/2 inhibitor PD98059 and partly by JNK inhibitor SP600125; while the decreases of cell proliferation induced by high concentrations of Cd were significantly restored by p38 inhibitor SB203580. Further analysis showed that phospho-ERK1/2 and phospho-JNK activities were increased with different concentrations of Cd, whereas phospho-p38 activity was markedly increased at high concentrations. Our findings suggested that low concentration of Cd induces the ERK and JNK pathways and promotes cell proliferation; while high concentration of Cd induces p38 pathway and inhibits cell proliferation. Activation of the ERK1/2 pathways seems to play a more important role than the JNK pathway in the biphasic effect of Cd on cell proliferation.

Survivin may enhance DNA double-strand break repair capability by up-regulating Ku70 in human KB cells.

BACKGROUND: Survivin, expressed in almost all types of human malignancies, functions as a key factor in radioresistance primarily by inhibiting apoptosis. This study was conducted to investigate whether survivin plays a role in the DNA repair process in the KB human squamous cell carcinoma cell line. MATERIALS AND METHODS: A stable KB cell line overexpressing survivin was established through the use of pIRES2-EGFP vector containing the coding region of survivin. Cells were then irradiated with X-rays and evaluated for DNA double-strand breaks (DSBs) by comet assay and flow cytometry for phospho-histone gammaH2AX. The protein levels of some DSB repair genes were detected by Western blotting analysis. RESULTS: Comet assay and flow cytometry for phospho-histone gammaH2AX showed that overexpression of survivin resulted in significantly fewer DSBs in irradiated cells. Among the DSB repair genes detected, the protein level of Ku70 was up-regulated in survivin-overexpressing KB cells. CONCLUSION: This finding suggests that survivin may enhance DSB repair capability in KB cells by up-regulating Ku70.

[Establishment of biological limit value of urinary S-phenylmercapturic acid for occupational exposure to benzene].

OBJECTIVE: To establish the biological exposure limit values of urinary S-phenylmercapturic acid (SPMA) for assessing occupational exposure to benzene. METHODS: Study participants were selected from 55 workers of benzene exposures below 32.5 mg/m(3). The concentration of personal exposure to benzene was measured by gas chromatography and sampled with personal sampler. The urine samples were collected at the end of work shift and individual internal exposure level was evaluated by determination of SPMA in urine by HPLC/MS method. Comparison of external and internal exposure was assessed by the relative internal exposure (RIE) index. RESULTS: The benzene exposure level ranged from 0.71 to 32.17 mg/m(3) (geometric mean 6.98 mg/m(3), median 7.50 mg/m(3)). The urinary SPMA at the end of the work shift were significantly correlated with benzene exposure, (microg/g Cr) = -8.625 + 18.367X (mg/m(3)), r = 0.8035, (P < 0.01). According to the occupational exposure limit for benzene in China and calculation of regression equation, the expected value of urinary SPMA was 101.58 microg/g Cr. Mean level of biotransformation of per mg/m(3) benzene to urinary SPMA was 18.23 microg/g Cr and the metabolic efficiencies of benzene transformation to urinary SPMA decreased with benzene exposure increased. CONCLUSION: Based on abroad documents and data, biological limit value for occupational exposure to benzene in China is recommended as follows: 100 microg/g Cr (47 micromol/mol Cr) for SPMA in the urine at the end of shift.