ELO2 Participates in the Regulation of Osmotic Stress Response by Modulating Nitric Oxide Accumulation in Arabidopsis

The ELO family is involved in synthesizing very-long-chain fatty acids (VLCFAs) and VLCFAs play a crucial role in plant development, protein transport, and disease resistance, but the physiological function of the plant ELO family is largely unknown. Further, while nitric oxide synthase (NOS)-like activity acts in various plant environmental responses by modulating nitric oxide (NO) accumulation, how the NOS-like activity is regulated in such different stress responses remains misty. Here, we report that the yeast mutant Δelo3 is defective in H₂O₂-triggered cell apoptosis with decreased NOS-like activity and NO accumulation, while its Arabidopsis homologous gene ELO2 (ELO HOMOLOG 2) could complement such defects in Δelo3. The expression of this gene is enhanced and required in plant osmotic stress response because the T-DNA insertion mutant elo2 is more sensitive to the stress than wild-type plants, and ELO2 expression could rescue the sensitivity phenotype of elo2. In addition, osmotic stress-promoted NOS-like activity and NO accumulation are significantly repressed in elo2, while exogenous application of NO donors can rescue this sensitivity of elo2 in terms of germination rate, fresh weight, chlorophyll content, and ion leakage. Furthermore, stress-responsive gene expression, proline accumulation, and catalase activity are also repressed in elo2 compared with the wild type under osmotic stress. In conclusion, our study identifies ELO2 as a pivotal factor involved in plant osmotic stress response and reveals its role in regulating NOS-like activity and NO accumulation.

Coordination of plant growth and abiotic stress responses by tryptophan synthase β subunit 1 through modulation of tryptophan and ABA homeostasis in Arabidopsis

To adapt to changing environments, plants have evolved elaborate regulatory mechanisms balancing their growth with stress responses. It is currently unclear whether and how the tryptophan (Trp), the growth-related hormone auxin, and the stress hormone abscisic acid (ABA) are coordinated in this trade-off. Here, we show that tryptophan synthase β subunit 1 (TSB1) is involved in the coordination of Trp and ABA, thereby affecting plant growth and abiotic stress responses. Plants experiencing high salinity or drought display reduced TSB1 expression, resulting in decreased Trp and auxin accumulation and thus reduced growth. In comparison with the wild type, amiR-TSB1 lines and TSB1 mutants exhibited repressed growth under non-stress conditions but had enhanced ABA accumulation and stress tolerance when subjected to salt or drought stress. Furthermore, we found that TSB1 interacts with and inhibits β-glucosidase 1 (BG1), which hydrolyses glucose-conjugated ABA into active ABA. Mutation of BG1 in the amiR-TSB1 lines compromised their increased ABA accumulation and enhanced stress tolerance. Moreover, stress-induced H₂O₂ disrupted the interaction between TSB1 and BG1 by sulfenylating cysteine-308 of TSB1, relieving the TSB1-mediated inhibition of BG1 activity. Taken together, we revealed that TSB1 serves as a key coordinator of plant growth and stress responses by balancing Trp and ABA homeostasis.

[A case of high-temperature steel bar penetration injury from scrotum to buttocks]

On November 17, 2013, the Second Affiliated Hospital of Kunming Medical University admitted a 23-year-old male patient with a high-temperature steel bar penetration injury from scrotum to buttocks who was transferred from another hospital. Expanded debridement, suture, and drainage of the perineum, right thigh, and right hip were performed as soon as possible after admission. A sputum suction tube was used as the guide mark for expanded debridement during the operation to ensure the accuracy of the direction and scope of expanded debridement. The incision was treated with vacuum sealing drainage (VSD) and full drainage. On the 20th day after the operation (the 25th day after admission), the unhealed wound was transplanted with split-thickness skin graft from the right thigh, and the drainage of the operation area and dressing change were strengthened. On the 53rd day after injury, the patient was discharged after complete wound healing. This case suggests that VSD after early debridement is an effective means to treat high-temperature steel bar penetration injuries.

[Research advances on autologous hair transplantation in the treatment of secondary cicatricail alopecia]

Secondary cicatricial alopecia (hereinafter referred to as cicatricial alopecia) after burn and trauma affects the aesthetic appearance and even the physical and mental health of patients, and reduces their quality of life and happiness. Autologous hair transplantation provides an idea for the treatment of cicatricial alopecia, which makes the transplanted hair show a natural growth state. This paper introduces the cicatricial alopecia and autologous hair transplantation and reviews the application and limitations of autologous hair transplantation in treating cicatricial alopecia.

Determination of Azide Ions in Blood by Pentafluorobenzyl Derivation Followed by GC-MS

Abstract

Objective To establish a method for determination of the azide ions in blood by gas chromatography-mass spectrometry （GC-MS） following pentafluorobenzyl derivatization. Methods A blood sample of 0.2 mL was placed into a 10 mL glass test tube, and the internal standard sodium cyanide, derivatization reagent pentafluorobenzyl bromide and catalyst tetradecyl benzyl dimethyl ammonium chloride were added in turn. After vortex mixing, the mixture was heated with low-power microwave for 3 min. After centrifugation, the organic phase was taken for GC-MS analysis. Results The azide ions in blood had a good linear relationship in the mass concentration range of 0.5 to 20 μg/mL. The lowest detection limit was 0.25 μg/mL and the relative recovery was 91.36%-94.58%. The method was successfully applied to a case of death from sodium azide poisoning. The mass concentration of azide ions in the blood of the dead was 11.11 μg/mL. Conclusion The method developed in this paper has strong specificity and is easy to operate, which is suitable for the rapid detection of azide ions in blood.

Identification of Tiletamine, Zolazepam and Their Metabolites in Drug Facilitated Sexual Assault by GC-QTOF-MS

Objective To identify tiletamine, zolazepam and their metabolites in samples from drug facilitated sexual assault by gas chromatography-quadrupole time of flight mass spectrometry （GC-QTOF-MS）. Methods Urine samples of victims were collected, and detected by GC-QTOF-MS after liquid-liquid extraction and concentration. The molecular formula of fragments ions was identified by determination of accurate mass numbers, to detect related substances. Results Tiletamine, zolazepam, three metabolites of tiletamine and two metabolites of zolazepam were identified in urine samples from actual cases. Conclusion GC-QTOF-MS provides abundant and accurate information of fragment ions mass numbers, which can be used for qualitative identification of tiletamine, zolazepam and their metabolites in drug facilitated sexual assault.

Molecular characterization and phylogenetic analysis of Taenia multiceps from China

Taenia multiceps, one of the most widely distributed zoonotic tapeworm parasites, is able to parasitize the small intestine of canids. The metacestode of T.multiceps is fatal to ruminants and causes important economic losses in livestock. However, molecular characteristics of T.multiceps and coenurus in China are still unclear. In this study, 36 goat isolates of the coenurus stage and 18 dog isolates of the adult stage of T.multiceps were obtained from three geographical areas in China and the isolated parasite above were analyzed by amplifying the partial of cytochrome coxidase subunit 1(pcox1), 12S ribosomal RNA (12S rRNA) from mitochondrial DNA (mtDNA) regions and an internal transcribed spacer (ITS) of ribosomal DNA (rDNA). These DNA sequences obtained from T.multiceps and coenurus were employed to evaluate the nucleotide diversity and confirm the relationship between T.multiceps and coenurus. Sequences variation were 0-1.4%, 0-1.5%, 0-4.2% for pcox1, 12S rRNA and ITS, respectively, among T.multiceps and coenurus isolates obtained in this study. In Sichuan province, sequence variations for Coenurus cerebralis isolated from Yaan city were 0-1.4% for pcox1, 0-1.0% for 12S rRNA and 0-2.1% for ITS. In Hunan province, variations were 0-1.0%, 0-1.5% and 0-3.3% for corresponding genes for non-coenurus cerebralis isolated from Changsha city, while variations of T.multiceps isolates from Xiangxi autonomous prefecture were 0-1.0%, 0-1.1% and 0-3.4% for pcox1, 12S rRNA and ITS, respectively. Phylogenetic analysis based on pcox1 sequences indicated that all cerebral and noncerebral metacestodes belong to T.multiceps. These results provide reference values for future molecular epidemiological and biological study on T.multiceps in dogs and intermediate hosts.

[Diagnostic value of serum chitinase-3-like protein 1 in chronic liver disease of significant fibrosis and cirrhosis]

Objective: To study the correlation between the level of serum Chitinase-3-like protein 1 (CHI3L1) and the significant liver fibrosis and liver cirrhosis in patients with chronic liver disease, and to evaluate its diagnostic value. Methods: 165 patients with chronic liver disease were selected, liver histopathological examination was performed to detect serum CHI3L1 concentration. Four indexes of hepatic fibrosis (type III procollagen, collagen IV, laminin, hyaluronic acid), aspartate aminotransferase/platelet ratio index (APRI) and FIB-4 (fibrosis- 4) scores were based on the pathological findings of liver biopsy and compared the advantages and disadvantages of serum CHI3L1 with other methods for the diagnosis of hepatic fibrosis and liver cirrhosis. A multivariate regression analysis model was created, and receiver operating characteristic curve was analyzed. Results: The level of serum CHI3L1 increased with increase of fibrosis stage and was highest in liver cirrhosis stage. In the period of S0 to 1, the levels of S2 to 3 and S4 were 62.82 (41.40 ~ 87.20), 70.94 (48.47 to 122.60) and 141.06 (78.18 ~ 197.40), and there were statistically significant differences between the groups (P < 0.001). The area under the curve for the diagnosis of significant liver fibrosis was 0.68 (0.60 to 0.77), and 0.74 (0.65 to 0.83) for cirrhosis in CHI3L1. Multivariate regression analysis showed that CHI3L1 was an independent predictor of significant fibrosis and cirrhosis. The combined diagnostic model based on CHI3L1, collagen IV and FIB-4 scores further improved the diagnostic value. The area under the curve for the diagnosis of significant fibrosis and cirrhosis was 0.79 (0.72 to 0.86) and 0.80 (0.73 to 0.87), respectively. Conclusion: CHI3L1 has a good diagnostic value in patients with chronic liver disease with significant fibrosis and liver cirrhosis. The diagnostic model in combination with other markers like Collagen IV and FIB-4 scores could further improve the diagnostic value and is worthy of further study.

[Effects of caspase-1 inhibitor VX765 on cold-restraint stress-induced acute gastric ulcer in mice]

Objective: To investigate the protective effects of caspase-1 inhibitor VX765 on gastric mucosa of mice with cold-restraint stress-induced acute gastric ulcer. Methods: Twenty-four specific pathogen free male C57BL/6J mice were divided into normal control group (NC), cold restrain group (CR), VX765 pre-treatment+ cold restrain group (VCR), and rabeprazole pre-treatment+ cold restrain group (RCR) according to the random number table, with 6 mice in each group. Mice in group NC were injected intraperitoneally with solution of 10 mL/kg dimethylsulfoxide (DMSO) and phosphate buffer solution (PBS). Mice in group CR were inflicted with acute gastric ulcer induced by cold-restraint stress 30 minutes after intraperitoneal injection of solution of DMSO and PBS. Mice in groups VCR and RCR were inflicted with acute gastric ulcer as above 30 minutes after intraperitoneal injection of solution of DMSO and PBS with dose of 12.5 μmol/kg containing 10 mg VX765 and 40 mg/kg containing 20 mg rabeprazole, respectively. Four hour after cold-restraint stress, serum content of tumor necrosis factor alpha (TNF-α) and interleukin 6 (IL-6)was determined by enzyme-linked immunosorbent assay. Gross condition of gastric tissue was observed. Ulcer index was evaluated. Pathological change of gastric tissue was observed with HE staining. The relative expression of IL-1β, IL-18, and cleaved-caspase-1 in gastric tissue were detected by Western blotting. Mice in group NC were detected as above at the same time point. Data were processed with one-way analysis of variance and Bonferroni test. Results: The serum content of TNF-α and IL-6 and the relative expression of cleaved-caspase-1, IL-1β, and IL-18 in gastric tissue of mice in group NC were significantly lower than those in group CR (with P values below 0.01). The content of the above-mentioned inflammatory indexes in serum and gastric tissue of mice in group VCR was significantly lower than that in group CR (with P values below 0.01). There were no statistically significant differences in content of the above-mentioned inflammatory indexes in serum and gastric tissue of mice between groups RCR and CR (with P values above 0.05). The content of the above-mentioned inflammatory indexes in serum and gastric tissue of mice in group VCR was significantly lower than that in group RCR (with P values below 0.01). Surface of gastric mucosa was smooth and morphology of mucosal cells was normal with clear structure of mice in group NC. Multiple hemorrhage of gastric mucosa, disorderly arrangement of mucosal cells, and large number of inflammatory cell infiltration around necrotic tissue were observed in mice of group CR. Decreased number of gastric mucosa bleeding, intact mucosal structure, and small amount of inflammatory cell infiltration around necrotic tissue were observed in mice of groups VCR and RCR. The ulcer indexes of mice in groups NC, CR, VCR, and RCR were 0, 18.7±1.1, 6.3±1.5, and 8.2±1.3, respectively. The ulcer index of mice in group NC was significantly lower than that in the other 3 groups (with P values below 0.05). The ulcer indexes of mice in groups VCR and RCR were close (P>0.05), which were significantly lower than ulcer index of mice in group CR (with P values below 0.05). Conclusions: VX765 can effectively inhibit the activation of caspase-1, reduce production of inflammatory factor, and alleviate inflammatory response, which have protective effects on gastric mucosa of mice with cold-restraint stress-induced acute gastric ulcer.

CATALASE2 functions for seedling postgerminative growth by scavenging H2 O2 and stimulating ACX2/3 activity in Arabidopsis

Increased fatty acid β-oxidation is essential for early postgerminative growth in seedlings, but high levels of H₂ O₂ produced by β-oxidation can induce oxidative stress. Whether and how catalase (CAT) functions in fine-tuning H₂ O₂ homeostasis during seedling growth remain unclear. Here, we report that CAT2 functions in early seedling growth. Compared to the wild type, the cat2-1 mutant, with elevated H₂ O₂ levels, exhibited reduced root elongation on sucrose (Suc)-free medium, mimicking soils without exogenous sugar supply. Treatment with the H₂ O₂ scavenger potassium iodide rescued the mutant phenotype of cat2-1. In contrast to the wild type, the cat2-1 mutant was insensitive to the CAT inhibitor 3-amino-1,2,4-triazole in terms of root elongation when grown on Suc-free medium, suggesting that CAT2 modulates early seedling growth by altering H₂ O₂ accumulation. Furthermore, like cat2-1, the acyl-CoA oxidase (ACX) double mutant acx2-1 acx3-6 showed repressed root elongation, suggesting that CAT2 functions in early seedling growth by regulating ACX activity, as this activity was inhibited in cat2-1. Indeed, decreased ACX activity and short root of cat2-1 seedlings grown on Suc-free medium were rescued by overexpressing ACX3. Together, these findings suggest that CAT2 functions in early seedling growth by scavenging H₂ O₂ and stimulating ACX2/3 activity.

[Advances in preparation and clinical application of amniotic membrane graft]

Amniotic membrane has been used as wound dressing for more than 100 years. With the development of the preservation and preparation techniques, amniotic membrane is widely used in ophthalmology, burns, plastic surgery, dentistry, and neurosurgery. In recent years, as more and more amniotic membrane is used in chronic wounds, it will be a new treatment method for wounds. This paper is a brief review about advances in preparation and clinical application of amniotic membrane graft.

Defective expression of polarity protein Par3 promotes cervical tumorigenesis and metastasis

OBJECTIVES

The aim of this study was to investigate whether the partition-defective 3 protein (Par3) regulates cervical carcinoma growth and metastasis.

MATERIALS AND METHODS

Immunohistochemistry (IHC) was used to analyze the expression of Par3 protein in samples from 89 cervical squamous cell carcinoma (CSCC) patients among Uyghur women. The specific short hairpin (shRNA) vector as well as eu- karyotic expression vector of PARD3 was transfected into SiHa cell lines. The variation of migration and invasion after transfection was determined using Transwell assays, cell cycle, and apoptosis were assayed by flow cytometry, respectively.

RESULTS

The incidence of CSCC was associated with reduced expression of Par3. Downregulation of Par3 was significantly associated with more advanced tumors (i.e., higher histological grade, lymph node involvement, and higher tumor stages) (p < 0.05 for all). Lost expression of Par3 promotes prolif- eration, inhibits apoptosis, and enhances migration and invasion. Loss of Par3 induces MMP9 expression and epithelial to mesenchymal transition (EMT) related genes (N-cadherin, E-cadherin, and β-catenin) expression changed in SiHa cells.

CONCLUSIONS

The reduced Par3 expression in cervical cancer indicates tumor-suppressive properties of Par3 that may be a marker of poor prognosis in cervical cancer patients, and the molecular determinants of epithelial polarity which have tumorigenesis enhancing impact, might through EMT.

An early decrease in serum HBeAg titre is a strong predictor of virological response to entecavir in HBeAg-positive patients

Quantification of HBeAg levels has been found to be useful in monitoring and predicting the outcomes of interferon and lamivudine treatment in HBeAg-positive patients. The aim of this study was to determine whether quantification of HBeAg at baseline and on treatment could predict which patients would achieve HBeAg seroconversion after 96 weeks of entecavir therapy. Sixty-five HBeAg-positive naïve chronic hepatitis B patients who were treated with entecavir at a dose of 0.5 mg once daily for 96 weeks were evaluated. Serum HBV DNA levels were assessed at baseline, week 24, 48 and 96; serum HBeAg levels were assessed at baseline, week 12, 24, 48, 72 and 96. Serum HBeAg levels were associated with a higher likelihood of HBeAg seroconversion to entecavir at weeks 96 than serum HBV DNA levels both at baseline and on treatment (at baseline: OR = 9.932, P = 0.003 vs. OR = 5.045, P = 0.036; on treatment: OR = 112.5, P < 0.0001 vs. OR = 47.782, P < 0.0001). A maintained reduction in HBeAg > 65% of pretreatment HBeAg values after 24 weeks of entecavir therapy is the strongest predictor for HBeAg seroconversion at week 96 (OR = 70.578, P < 0.0001). Quantification of HBeAg at the start and early during therapy showed a higher predictive value than that of HBV DNA for HBeAg seroconversion by entecavir. A significant decrease in serum HBeAg levels at week 24 may be a useful on-treatment measurement in the early phase for predicting HBeAg seroconversion and identifying patients who will most likely benefit from finite entecavir treatment.

Preliminary observations on the antifatigue effects of longan (Dimocarpus longan Lour.) seed polysaccharides

The antifatigue effects of the hot-water extract of longan (Dimocarpus longan Lour.) seeds were studied in mice. Longan seed polysaccharides were administered at doses of 50, 100, 200 and 400 mg/kg and antifatigue activity was evaluated using a swimming test, along with the determination of serum urea nitrogen, hepatic glycogen and blood lactic acid content. The results show that longan seed polysaccharides, in doses ranging from 50 to 100 mg/kg, extended swimming time, increased hepatic glycogen (p < 0.01, n = 10), reduced blood urea nitrogen (p < 0.01, n = 10) and decreased blood lactic acid (p < 0.01, n = 10) in the mice. Therefore longan seed polysaccharides may have potential as an antifatigue agent.

[Studies on the chemical constituents of Zanthoxylum dimorphophyllum Hemsl. var spinifolium Rhed. et Wils]

AIM

To study the chemical components from the dried roots of Zanthoxylum dimorphophyllum Hemsl. var spinifolium Rhed. et Wils.

METHODS

Modern chromatography was used to isolate chemical components and the compounds isolated from Zanthoxylum dimorphophyllum Hems1. var spinifolium Rhed. et Wils were identified by various spectral methods.

RESULTS

Five compounds were isolated and identified as 6-(2',3'-dihydroxy-3'-methybutyl)-7-acetoxy-2H-1-benzopyran-2-one (I), 6-(2',3'-dihydroxy-3'-methybutyl)-7-(beta-D-glucopyranosyloxy)- 2H-1-benzopyran-2-one (II), hexacosanoci acid (III), aurepten (IV), 6-[6'-O-(-deoxy-alpha-L-mannopyranosyl)-beta-D-benzopyran-4-one (V).

CONCLUSION

All of the above compounds were isolated from the plant for the first time, among them, I is a new compound.

[Relationship between heat stress suppression of neuroapoptosis and activation of nuclear kappa B in primary cultured rat cerebellar granule cells]

It has been well demonstrated that heat stress response (HSR) plays a crucial role in protecting cells from injury induced by various pathological stimuli. However, the protective mechanism of HSR is only poorly understood. The object of this article was to further investigate the relationship between the protective role of heat stress response and activation of NF-kappa B in primary cultured rat cerebellar granule cells. Heat stress was induced by hyperthermia (43+/-0.5 degrees centigrade), and DNA binding activity of NF-kappa B was determined with electrophoretic mobility shift assay (EMSA). Neuroapoptosis was measured by Hoechst 33258, agarose gel electrophoresis and flow cytometry (FCM) analysis. The results showed that the neurons treated with low potassium for l6 h could induce neuroapoptosis and promote the activity of nuclear kappa B. Heat stress treatment for 30, 60 and 90 min could suppress neuroapoptosis and the activity of nuclear kappa B induced by low potassium in a time-dependent manner. Activation of NF-kappa B using 100 nmol/L phorbol 12-myristate l3-acetate (PMA) could promote antiapoptotic action of heat stress response. In contrast, when NF-kappa B activation was inhibited by 10 micromol/L pyrrolidine dithiocarbamate derivatives (PDTC), heat stress did not provide protection against cell apoptosis induced by low potassium. The results suggest that the neuroprotection of heat stress has no relation to the suppression of NF-kappa B activity, and activation of NF-kappa B may promote antiapoptotic action of heat stress.

[Studies on chemical constituents in root of Rumex patientia L]

OBJECTIVE

Investigating the chemical constituents in the root of Rumex patientia.

METHOD

Compounds were separated by rechromatography on silica gel. Their structures were determined by spectral analysis and chemical evidence.

RESULT

Eight compounds were isolated and identified as 5-methoxy-7-hydroxy-1 (3H)-benzofuranone (I), 5, 7-dihydroxy-1 (3H)-benzofuranone(II), nonadecanoic acid-2,3-dihydroxypropyl ester(III), torachrysone-8-O-beta-D-glucopyranoside(IV), gallic acid(V), beta-sitosterol(VI), beta-sitosterol-3-O-beta-D-glucopyranoside(VII) and catechin(VIII).

CONCLUSION

Compound III is a new natural products, and compounds I and II were obtained from this plant for the first time.

[Neuroprotective effect of alpha-dihydroergocryptine depends on activation of nuclear factor kappa B]

AIM

To investigate the relationship between the neuroprotective effect of alpha-dihydroergocryptine (alpha-DHEC) and the activation of nuclear factor Kappa B (NF-Kappa B).

METHODS

Adult male rats were subjected to cerebral ischemia induced by middle cerebral artery occlusion (MCAO). DNA binding activity of NF-Kappa B was determined with electrophoretic mobility shift assay (EMSA) in animals subjected to varying durations of cerebral ischemia. Neuroapoptosis induced by ischemic damage was measured by deoxynucleotidy transferase-mediated dUTP nick end labeling (TUNEL) assay and flow cytometry (FCM) analysis.

RESULTS

No change was observed in nuclear NF-Kappa B DNA binding in normal animal. A low level of constitutive NF-Kappa B DNA binding was detected in animals subjected to cerebral ischemia of 1 h, and significant increase in the amount of active NF-Kappa B in nuclear extracts was observed after cerebral ischemia of 3 h, 6 h, and 12 h. Peak of NF-Kappa B DNA binding was observed at the time point of 3 h. Animals subjected to cerebral ischemia of 3 h potentially initiates neuroapoptosis and activates NF-Kappa B in nuclear extract. Alpha-DHEC (100 micrograms.kg-1 and 150 micrograms.kg-1) showed significant protective effect on neuroapoptosis-induced by cerebral ischemia of 3 h, and inhibiting NF-Kappa B activation using 100 mg.kg-1 pyrrolidinedithiocarbamate (PDTC) in the continuous presence of alpha-DHEC, the neuroprotective effect of alpha-DHEC was blocked.

CONCLUSION

The findings suggest that the neuroprotetive effect of alpha-DHEC may depend on the activation of NF-Kappa B.

HLA and longevity or aging among Shanghai Chinese

Twenty-two centenarians and one hundred and seventy-nine nonagenarians (mean age 93 +/- 1.04 years) in the Shanghai Region of China were phenotyped for alleles of A (13 types), B (21 types) and C (6 types) loci of the human leukocyte antigen (HLA). The frequencies of HLA antigens were compared with 211 healthy adults whose ages ranged from 20 to 50 years. It was observed that A9 was highly associated with longevity (frequency in the longevity group is 38%, the control group 24%, P = 0.002). A30 showed marked inverse correlation (frequency in the longevity group is 8%, the control group 17%, P = 0.008). Cw3, Cw6 and Cw7 were also inversely correlated (P = 0.02, 0.04 and 0.02, respectively). Thus, it is likely that A9 may contribute to longevity while A30, Cw3, Cw6 and Cw7 may be associated with aging. The average superoxide dismutase (SOD) contents of erythrocytes in 48 cases with the HLA-A9 (without A30) antigen in the longevity group and in 13 cases with the HLA-A30 (without A9) antigen in the control group were 555 +/- 96 and 593 +/- 58 micrograms/gHb, respectively (t = 1.375, P > 0.05).

Effects of silica on serum phospholipid, lipid peroxide and morphological characteristics of rat lung

The effects of instilled silica have been studied on the serum-phospholipid (PL), lipid peroxide (LPO) and histopathology of rat lung up to 140 days from the first day of instillation. Silica induced relatively higher serum-PL throughout the experiment. The level of LPO also increased appreciably. They presented positive linear correlation. The early lesion was acute alveolitis with silica particles. These lesions became silicotic nodules on the 30th day, which then were enlarged gradually and fused by fibrosis. Alveolar macrophages (AM) were activated and surface structure was damaged. These results indicate that instilled silica can induce lipid peroxidation of cell membrane and selective accumulation of lung PL.

Serological identification of HLA-B13 subtypes

A serological approach is used to confirm subtypes of HLA-B13 originally observed by one-dimensional isoelectric focusing (1D-IEF). Sixty anti-B13 alloantibody sera were screened against Chinese panel cells. Two clusters of sera showing distinct reactive patterns were identified. One is a shorter reactive pattern than the other. Using these serological reaction patterns, the B13 antigen can be divided into two subtypes, B13.1 and B13.2, in the Chinese population. These serological subtypes appear to correlate well with the 1D-IEF patterns of B13 subtypes. The serological subtyping is also in agreement with the differences in nucleotide sequence previously determined to exist in B13 antigen subtypes. Family studies show that both B13.1 and B13.2 segregate as HLA-B locus alleles. Gene frequencies for B13.1 and B13.2 were 0.0676 and 0.0612, respectively, in our study population of 337 southern Han Chinese.

A "new" HLA-C specificity, CSH-2, restricted to Oriental populations

The high frequency of C-locus blank alleles in different races suggests the existence of an undetected antigen. We have identified a new C-locus antigen, tentatively named CSH-2, which is present in Oriental populations, but is apparently not present in Caucasoid, or Black populations. This new specificity was defined by a single strong monospecific antiserum, named ZHA114, which was obtained by planned immunization.