[Lymphocyte apoptosis in asthmatic patients and its molecular mechanism]

OBJECTIVE

To assess the apoptosis rate of peripheral blood lymphocytes isolated from patients with asthma and explore its molecular mechanism.

METHODS

Lymphocytes were isolated with ficoll-hypaque gradient method and T lymphocytes were further isolated with nylon pili. T lymphocytes were stimulated by anti- CD3+ antibody for 0, 24, 48, 72 hours in vitro and the apoptosis rates were measured with in situ tailing technique. At the same time, Bcl-2 gene expression and Bax gene expression were observed with in situ hybridization.

RESULTS

The percentages of apoptosis cell in T lymphocytes from patients with asthma were significantly decreased and the timing delayed in comparison with those in normal controls (P < 0.01). The Bcl-2 mRNA expression in T lymphocytes was significantly increased in different time points than in normal controls (P < 0.01), but Bax mRNA expression in T lymphocytes was remarkably decreased (P < 0.01). The rates of Bcl-2/Bax mRNA could not reach the state of the controls until 72 hours from the begining of the stimulation with the anti-CD3+.

CONCLUSIONS

The inhibited apoptosis might be one of the reasons for the chronic persistent inflammation in the airways in asthmatic patients and the imbalance between Bcl-2 gene expression and Bax gene expression may be one of the molecular mechanisms for the inhibited apoptosis.

Phosphorylation of splicing factor SF1 on Ser20 by cGMP-dependent protein kinase regulates spliceosome assembly

Splicing factor 1 (SF1) functions at early stages of pre-mRNA splicing and contributes to splice site recognition by interacting with the essential splicing factor U2AF65 and binding to the intron branch site. We have identified an 80 kDa substrate of cGMP-dependent protein kinase-I (PKG-I) isolated from rat brain, which is identical to SF1. PKG phosphorylates SF1 at Ser20, which inhibits the SF1-U2AF65 interaction leading to a block of pre-spliceosome assembly. Mutation of Ser20 to Ala or Thr also inhibits the interaction with U2AF65, indicating that Ser20 is essential for binding. SF1 is phosphorylated in vitro by PKG, but not by cAMP-dependent protein kinase A (PKA). Phosphorylation of SF1 also occurs in cultured neuronal cells and is increased on Ser20 in response to a cGMP analogue. These results suggest a new role for PKG in mammalian pre-mRNA splicing by regulating in a phosphorylation-dependent manner the association of SF1 with U2AF65 and spliceosome assembly.

[Effect of anti-CD4+ human/murine chimeric antibody on the proliferation and apoptosis of lymphocyte in patients with asthma]

OBJECTIVE

To investigate the effects of anti-CD4+ human/murine chimeric antibody on the proliferation and the apoptosis of peripheral blood lymphocytes (PBL) in patients with asthma.

METHODS

PBL isolated from patients with asthma were cultured with 50 mg/L, 100 mg/L anti-CD4+ human/murine chimeric antibody and anti-CD3+ McAb (10 mg/L) for 0, 24, 48 h in vitro, the apoptosis cell percentage were detected by flow cytometry and in situ end-labeling technique of fragmental DNA as well as the proliferation of PBL were detected by MTT method.

RESULTS

Comparing with normal controls, the apoptosis cell percentage was significantly decreased by stimulation with anti-CD3+ McAb for 24 h and 48 h, the proliferation of lymphocyte was increased in patients with asthma; the apoptosis cell percentage of patients with asthma was significantly increased (P < 0.01, respectively) with the cell cultured with 50 mg/L or 100 mg/L anti-CD4+ human/murine chimeric antibody for 24 h or 48 h At the same time the lymphocyte proliferation was inhabited (P < 0.01, respectively).

CONCLUSIONS

It is demonstrated that the proliferation of PBL in patients with asthma were increased and the apoptosis cell percentage were decreased, anti-CD4+ human/murine chimeric antibody had inhibited the proliferation of T lymphocyte and had enhanced the T lymphocyte apoptosis. The anti-CD4+ human/murine chimeric antibody may be potentially useful for the biotherapy of asthma.

[Treatment of benign prostatic hyperplasia with laser through the endoscope]

OBJECTIVE

To evaluate the effect of transurethral laser prostatectomy (TULP) and its relation with the size of prostate.

METHODS

469 benign prostatic hyperplasia receiving TULP from 1988 to 1998 were reviewed retrospectively, and the methods of operation and preoperative and postoperative symptom were compared. The effect of 233 patients undergoing TULP was compared with the size of the prostate.

RESULTS

The average value for IPSS of 469 patients decreased from 26.7 (preoperation) to 14.2 (postoperation). The mean value of maximum uroflow rate increased from 6.2 ml/s (preoperation) to 11.8 ml/s (postoperation). No difference was seen in postoperative effect between the transurethral contact and noncontact laser prostatectomy. If the estimating weight of prostate exceeded 50 g, the maximum flow rate after 3 years was decreased evidently, the value of IPSS increased to over 20.

CONCLUSIONS

If the estimating weight of prostate is less than 50 g, TULP is indicated.

Prevalence of lesions and body condition scores among female swine at slaughter

OBJECTIVE

To determine prevalence of foot lesions, dermatitis, shoulder lesions, mammary gland abnormalities, and visceral lesions, and body condition scores among culled female swine at slaughter.

DESIGN

Observational study.

ANIMALS

Culled gilts and sows killed during a 1-week period at a Midwest slaughterhouse.

PROCEDURE

Carcasses were examined, and lesions were recorded. Body condition was scored on the basis of standard criteria.

RESULTS

58.9% (1,029/1,747) of the carcasses had foot lesions, 67.3% (1,178/1,751) had dermatitis, and 4.6% (80/1,751) had shoulder lesions. Body condition score was significantly associated with detection of dermatitis and shoulder lesions. Mean +/- SE number of teats (n = 1,432 carcasses) was 13.86 +/- 0.02. Mean numbers of normal-appearing teats in the left and right mammary chains were 6.57 +/- 0.02 and 6.58 +/- 0.02, respectively. Feet from 48% (688/1,433) of the carcasses were condemned. Visceral lesions were found in 48.8% (624/1,278) of the carcasses; of the carcasses with lesions, 412 (66%) had liver spots, and 268 (42.9%) had pneumonia.

CLINICAL IMPLICATIONS

Lesions that potentially could have adversely affected production were found in a large percentage of culled gilts and sows at slaughter. Knowledge of lesions commonly found at slaughter may help direct changes in herd health programs.

[Cloning and sequencing of fusion protein gene of recombinant GM-HBsAg]

GM-CSF is an effective adjuvant for immunology, it was used to improve the immunological function of antigen and to increase the anti-HBs responses. Through using polymerase chain reaction (PCR) technique, we amplified 384 bp and 846 bp gene fragments from GM-CSF and HBsAg. The products were extracted and purified; a 1230 bp gene fragment was obtained by T4 DNA linkage. This amplified product was cloned into pUC19 vector. The positive clones were screened and the inserted fragment was determined by restriction enzymes. The gene fragment length determined is 1230 bp, the sequence analysis showed that the gene fragment is GM-CSF-HBsAg gene. The successful construction of GM-HBsAg fusion protein gene provides basis for research of its biological activity and expression.

Influence of mating frequency on sow reproductive performance

Gilts and sows were bred one, two, or three times during a single estrous period in a commercial herd for evaluating the effect of mating frequency on reproductive performance. Estrus detection started at approximately 0630 daily by applying back pressure to females with the presence of a mature boar. Natural mating was used. Gilts detected in estrus were mated in the morning of d 1 (AM), the morning of d 1 and 2 (AM-AM), and the morning and afternoon of d 1 and morning of d 2 (AM-PM-AM) for mating frequencies 1, 2, and 3, respectively. Sows were bred in the AM, AM-AM, AM-PM-AM (1), and morning of d 1 and morning and afternoon of d 2 [AM-AM-PM (2)] for mating frequency 1, 2, 3 (1), and 3 (2), respectively. Breeding events in the morning and afternoon started at approximately 0730 and 1530. Females were randomly assigned to a mating frequency. Boars were randomly assigned to each breeding event. In total, 256 gilts and 766 sows were involved in the study. Gilts with a single mating (76.5%, P = .06) and triple matings (80.4%, P < .05) had higher farrowing rates than those with double matings (65.3%). No differences (P > .1) in the farrowing rates of sows were observed between mating frequencies 1, 2, 3 (1), and 3 (2). Double-mated gilts had more (P < .03) total born (9.7 vs 8.6) and pigs born alive (9.3 vs 8.2) than did single-mated gilts. There were no differences (P > .3) in total born and pigs born alive in sows between mating frequencies. We concluded that triple-mating gilts and sows did not improve farrowing rate and litter size compared with single and double matings. There were no differences in farrowing rate and litter size between double- and single-mated sows. Gilts with double matings had a larger litter size than those with a single mating.

Expression and localization of membrane type 1 matrix metalloproteinase in tooth tissues

Matrix metalloproteinases (MMPs) have been detected in forming dental enamel and are thought to play an important role during enamel biomineralization. Membrane-type 1 matrix metalloproteinase (MT1-MMP) is a membrane bound member of the MMP gene family that has previously been shown to be expressed by cells associated with bone and cartilage formation (osteoclasts, osteoblasts and chondrocytes). Thus, we asked if MT1-MMP was also expressed by the cells responsible for the formation of enamel and dentin. A porcine MT1-MMP cDNA composed of 3284 bp was isolated from an enamel organ-specific cDNA library. Multiple tissue Northern blot analysis revealed that the MT1-MMP message was expressed highly in the enamel organ and pulp organ when compared to the expression levels observed in other non-mineralizing tissues. Northern blot analysis of stage-specific enamel organs (early secretory, late secretory, or maturation stage) and their corresponding pulp organs revealed that MT1-MMP expression increased as the dentin matured. In the enamel organs, however, the MT1-MMP message level became reduced only during the late secretory stage. Immunohistochemical analysis showed that MT1-MMP was present on the surface of the cells (ameloblasts and odontoblasts) responsible for dentin and enamel formation. Thus, MT1-MMP is highly expressed in developing tooth tissues and may play a role in the biomineralization of enamel and dentin.

Influence of lactation length and feed intake on reproductive performance and blood concentrations of glucose, insulin and luteinizing hormone in primiparous sows

Twenty-four pregnant gilts were assigned to four experimental treatments in a 2 x 2 factorial arrangement. The first factor was lactation length (12 vs. 21 days) (LL); the second factor was a provided amount of diet (FF, full feeding vs. low, 2 kg/day). The same diet (1% lysine and 3.27 Mcal ME/kg) was used from farrowing to 1 day after weaning. Sow body weight, backfat thickness (BF), litter weights, and blood samples were measured prior to and 1 day after weaning. Sows were monitored for estrous once daily in the presence of a boar until 35 days after weaning or until estrous was detected. Average feed intake during lactation (ADFI) was 1.9 (low) and 4.0 (FF) kg/day. ADFI among individual sows varied from 1.8 to 4.9 kg/day. Positive effects of both LL and feed intake treatments were found (P < 0.05) on sow body weight loss, backfat loss, glucose concentrations, mean luteinizing hormone (LH) concentrations, and LH pulse frequency prior to weaning, and farrowing-to-estrous interval. Greater concentrations of insulin prior to weaning were associated only with feed intake treatment (P < 0.05). No interactions between LL and feed intake treatments were found in any measures except for sow body weight loss. Using regression analysis, greater lactation feed intake was associated with greater concentrations of insulin and glucose, greater LH pulse frequency prior to weaning and shorter farrowing-to-estrous interval in both LL treatments. We suggest that greater feed intake during lactation improves farrowing-to-estrous interval through LH release regardless of LL treatment.

[The influence of side-to-side portacaval shunt plus enhancement of perfusion of hepatic artery on cirrhotic liver: an experimental study]

OBJECTIVE

To for improving the perfusion of liver, we designed an operation of portacaval shunt (PCS) plus enhancement of perfusion of hepatic artery (EPHA).

METHOD

48 wistar rats were divided into 4 groups randomly. group I (normal control), group II (liver cirrhotic control), group III (PCS on liver cirrhosis), and group IV (PCS + EPHA on liver cirrhosis). The EPHA was performed by the ligation of the left gastric and splenic artery. Liver function tests, liver biopsy, and nuclide hepatobiliary dynamic imaging (NHDI) were performed on the 2nd week and the 6th month after operation.

RESULT

In NHDI, the peak time was short (P < 0.05) and the excretive rate was high (P < 0.01). The liver function and the proliferative degree of the fibrotic tissue of the liver were perfected significantly (P < 0.05) in the group IV compared with the group III after operation.

CONCLUSION

PCS + EPHA can increase the perfusion of the hepatic artery, maintain the liver function and delay liver cirrhosis, and overcome the side effects of PCS. It is a new surgical technique in treating portal hypertension.

Expression and regulation of hFIX minigene and cDNA driven by beta-casein gene in mouse mammary gland

Mammary gland specific expression vectors for human clotting factor IX (hFIX) and LacZ reporter gene driven by bovine beta-casein gene were constructed. Vectors were packaged by stearylamine (SA) liposome and were transferred to lactating mice via tail vein. Both hFIX and Lac2 gene could be expressed in the mammary gland of the treated mice. The highest production of hFIX protein was 80.28 ng per mL milk, and more than 85% of hFIX protein appeared to be gamma-carboxylation and biologically active. The results suggested that the 2.0 kb sequence of beta-casein gene including promoter, exon 1 was effective to drive hFIX gene expression in mammary gland and intron 1 of beta-casein gene had an effect on the tissue specific expression. The expression level in mouse milk injected with hFIX minigene vector containing hFIX endogenous intron 1 was increased by above 3 times of that injected with hFIX cDNA vector.

Management factors associated with swine breeding-herd productivity in the United States

A database containing 24 key production measurements was created by abstracting data files of 673 U.S. farms which participated in the PigCHAMP data-share program in 1995. Summary statistics for breeding-herd performance data were presented for the Cornbelt and the South or Eastern regions. Eight models were built to assess the association between production system, operation management factors and productivity outcomes. Lactation length, percentage of multiple matings, parity of culled sows, percent gilts in the breeding-female inventory, and female culling rate were the management factors identified as having important associations with productivity outcomes. For example, shorter lactation length, higher percentage of multiple matings, and lower culling rate were associated with more pigs weaned per mated female per year. In addition, a lower percentage of gilts in the breeding-female inventory and a higher percentage of multiple matings were associated with fewer average non-productive female days. We recommend that producers change their management systems to decrease lactation length, the percentage of gilts in the breeding-female inventory, and female culling rate, and increase percentage of multiple matings in order to improve breeding-herd productivity on swine farms.

[Longitudinal evaluation of vocal function following thyroplasty type I for the treatment of unilateral vocal paralysis]

Longitudinal changes of vocal efficiency and stability following thyroplasty type I were analysed. Fifty-three patients with unilateral vocal fold paralysis underwent vocal function evaluation preoperatively and 1, 3 and 6 months postoperatively. Vocal function assessment included videostrobolaryngoscopic examination, acoustical and aerodynamic analyses, and perceptual ratings of voice. Parameters including glottic gag size, maximum phonation time, glottic flow rate, jitter, harmonic to noise ratio, breathness, hoarseness, loudness and phrasing showed significant improvement after thyroplasty and remained stable within 1 month with only slight fluctuations over a 6 month period. Postoperative voice outcome was not affected by age, sex, duration of vocal symptoms, etiology of paralysis, or preoperative pulmonary function.

Incomplete embryonic lethality and fatal neonatal hemorrhage caused by prothrombin deficiency in mice

Deficiency of blood coagulation factor V or tissue factor causes the death of mouse embryos by 10.5 days of gestation, suggesting that part of the blood coagulation system is necessary for development. This function is proposed to require either generation of the serine protease thrombin and cell signaling through protease-activated receptors or an activity of tissue factor that is distinct from blood clotting. We find that murine deficiency of prothrombin clotting factor 2 (Cf2) was associated with the death of approximately 50% of Cf2(-/-) embryos by embryonic day 10.5 (E10.5), and surviving embryos had characteristic defects in yolk sac vasculature. Most of the remaining Cf2(-/-) embryos died by E15.5, but those surviving to E18.5 appeared normal. The rare Cf2(-/-) neonates died of hemorrhage on the first postnatal day. These studies suggest that a part of the blood coagulation system is adapted to perform a developmental function. Other mouse models show that the absence of platelets or of fibrinogen does not cause fetal wastage. Therefore, the role of thrombin in development may be independent of its effects on blood coagulation and instead may involve signal transduction on cells other than platelets.

Construction of mammary gland-specific expression vectors for human clotting factor IX and its secretory expression in goat milk

Two expression vectors comprised of mouse matrix attachment regions (MARs), bovine beta-casein gene sequence, human factor IX (hFIX) minigene, and cDNA, pMCIXm and pMCIX, were constructed for the purpose of a mammary gland bioreactor. A secretory expression system of hFIX protein in milk was made using stearylamine (SA) liposome to transfect plasmid DNA directly into the mammary gland lobule of a lactating goat. The highest production of hFIX in goat milk was 13.7 ng/ml 3 days after transfection, and the hFIX production in the goat mammary gland transfected with pMCIXm containing hFIX minigene was obviously higher than that transfected with pMCIX containing hFIX cDNA. Activity immuno-analysis and the barium citrate absorption method showed that > 90% hFIX protein in milk appeared to be a gamma-glycosylated and biological activity. This result confirmed the validity of the constructed vectors for further transgenic study, and this assay could also find its success in the evaluation of a foreign gene expression and secretion in the milk as a rapid detection system using liposome to transfect DNA directly into the goat mammary gland.

[Clinical analysis of laser prostatectomy]

OBJECTIVE

To study the effect of laser prostatectomy for benign hypertrophy of prostate by transurethral noncontact laser ablation.

METHOD

204 patients with benign prostatic hyperplasia were treated by transurethral noncontact laser ablation.

RESULT

163 patients resumed urination in a week, and 37 in two weeks. Four patients were treated by open procedure. Patients were followed up for 14 months. Symptomatic scores (I-PSS) exceeded the middle rank in 90% patients and the maximum urinary flow rate was 89%.

CONCLUSION

It is an effective method for adjusting the strength, direction, range and frequency of laser to prevent bleeding, perforation and long-term urethral stricture.

Suicide effect on rat gliomas mediated by recombinant adenovirus thymidine kinase/acyclovir system

OBJECTIVE

To establish the replicated-deficient recombinant adenovirus-mediated thymidine kinase/acyclovir (Adtk/ACV) system and to evaluate its suicide effect on rat C6 brain gliomas in vitro and in vivo.

METHODS

The plasmid pAdtk and pJM17 were co-infected into 293 cells (adenovector packaging cells) and the results were identified by polymerase chain reaction (PCR) assay. After the glioma C6 cells were transduced by Adtk at different multiplicity of infection (MOI) and exposed to different concentrations of ACV or gancyclovir (GCV), the cell survival curves were studied, and the cell surface was observed with scanning electronic microscopy (SEM). C6 gliomas in vivo at different inoculation days were injected with Adtk intratumorally and ACV intraperitoneally daily, and the survival duration and histologic changes of the rats were observed.

RESULTS

The infectious Adtk virions had a suicide effect which was enhanced with the increase in MOIs of Adtk and ACV doses along with bystander effect. Under scanning electronic microscope, special pathologic changes were observed. ACV had a similar effect as GCV but a higher dose was used. The survival duration in day 3, day 6 and day 8 groups exceeded 90 days, and the rats in day 10 group survived 28.5 +/- 4.6 days, but the survival duration in untreated C6 group and AdLacZ/ACV (adenovirus-mediated LacZ/ACV) treated group were 16.8 +/- 3.1 and 14.0 +/- 2.2 days respectively.

CONCLUSION

Adtk/ACV system can effectively kill the rat brain gliomas in vitro and in vivo.

Polymorphism of DXS102 locus in Chinese population and its application to gene diagnosis in hemophilia B family

OBJECTIVE

To establish the polymorphism of DXS102 locus from Xq26.3-27.1 in Chinese population for the gene diagnosis in Hemophilia B family.

METHODS

DNA was extracted from blood samples obtained from Shanghai unrelated volunteer donors with phenol-chloroform method. A total of 23x chromosomes (154 from females, 80 from males) were studied. A hemophilia B family in which a hemophilia B patient has received gene therapy was analyzed. The polymorphism of DXS102 locus in Chinese population was determined with amplified fragment length polymorphisms assay (Amp-FLP), denaturing polyacrylamide gel electrophoresis, silver stain detection. Short tandem repeats (STRs) linkage analysis was used to conduct gene diagnosis in hemophilia B family.

RESULTS

Eight alleles were found at DXS102 locus, of which two alleles were first reported. The repeated number of AC dinucleotide ranges from 13 to 21. And the values of the observed heterozygosity, calculated heterozygosity and polymorphism information content(PIC) were 0.87, 0.80, 0.80 respectively. It was also found that the difference of the allele frequencies of DXS102 in Chinese and European populations was significant. By using the linkage analysis of the DXS102 locus, a family with a hemophilia B patient receiving gene therapy in 1994 was analyzed and meanwhile a carrier in that family was then detected.

CONCLUSIONS

The polymorphism of DXS102 locus reveals significant difference between Chinese and European populations. DXS102 locus can be used as a promising marker for gene diagnosis in hemophilia B family.

[Application of capillary electrophoresis on environmental analysis]

A review of applications of capillary electrophoresis (CE) on environmental analysis is presented, based mainly on the worldwide published works in the latest years. The current achievements and application potential of CE in the field of environmental analysis are included with 58 references.

[Effects of nitric oxide on the airway inflammation and lymphocyte proliferation in sensitized rats]

OBJECTIVE

To investigate the relations between intrinsic nitric oxide (NO) and airway inflammation and lymphocyte proliferation in bronchial asthma.

METHOD

The rat model of asthmatic airway inflammation was established by first sensitizing and then challenging the animals with ovalbumin. NO synthase (NOS) inhibitor and NO precursor were then applied and their influences on the airway inflammatory cell numbers and on the numbers of mIL-2R positive lymphocytes were observed.

RESULT

In vivo experiments showed that normal control rats (n = 6) did not have eosinophils in their submucosal of airways while in the sensitized animals (n = 6) eosinophils [23 +/- 5 (average cell counts per microscopic visual field, the same below) as well as lymphocytes (34 +/- 5) and mIL-2R positive cells (12 +/- 3) were found in significantly increased numbers in the airways. The application of NOS inhibitor significantly reduced eosinophils (13 + 3, P < 0.05) and mIL-2R positive cells (4.3 +/- 1.6, P < 0.05) in the sensitized animals and the number of lymphocytes was also decreased (28 +/- 4) although it did not reach the significant level. At the same time the spleen cell proliferation was inhibited (P < 0.05) and the mIL-2R positive spleen cell numbers were reduced (P < 0.05). On the contrary, the application of NO precursor resulted in the further increase of the numbers of eosinophils, lymphocytes and mIL-2R positive cells although the differences were not statistically significant. In vitro experiments showed that NOS inhibitor inhibited the proliferation of cultured spleen lymphocytes as well as their mIL-2R expression (P < 0.05). NO precursor, when used in low dose, could promote the proliferation and mIL-2R expression of spleen cells (P < 0.05); but high dose of it showed inhibiting effect on the spleen cells (P < 0.05).

CONCLUSION

Intrinsic NO at a suitable level is important in the regulation of the proliferation and activation of lymphocytes in the airways with allergic inflammation in the sensitized rats. This research is conducive to the understanding of the pathogenesis of the asthmatic airway inflammation and to investigating of new therapeutic approaches.

[The influence of intrahepatic transplantation of hepatocytes and insular cells on liver cirrhosis]

OBJECTIVE

To protect liver function, we used the cirrhotic rats to study whether the postshunt intrahepatic transplantation of hepatocytes and insular cells via hepatic artery can improve liver function.

METHOD

We irrigated the cirrhotic liver of rat via hepatic artery with hepatocytes and insular cells and observed the influence of this method on liver function.

RESULT

The improvement of TP, ALB and TBIL in the experimental group were significant, and there was significant difference in these parameters between the experimental and control groups (P < 0.01). Light microscopic examination of liver fibrosis and immunohistochemistry and data analysis of I, II collagens also showed significant difference (P < 0.05).

CONCLUSION

The intrahepatic transplantation of hepatocytes and insular cells via hepatic artery can not only improve liver function, but also increase the degradation of liver collagens and reverse the course of liver cirrhosis.

[Determination of the polymorphism of DXS102 locus and its application in gene diagnosis]

OBJECTIVE

To determine the polymorphism of DXS102 and use it in gene diagnosis in hemophilia B.

METHODS

Amp-FLP and linkage analysis on 234 chromosomes.

RESULTS

Eight alleles were found at DXS102 locus. The number of AC dinucleotide repeats ranged from 13 to 21. And the observed heterozygosity, calculated heterozygosity and polymorphism information content(PIC) were 0.87, 0.80 and 0.80, respectively. It was noted that the difference of the allele frequencies of DXS102 in Chinese and European populations was significant. By using the linkage analysis of the DXS102 locus, a family with a hemophilia B patient receiving gene therapy in 1994 was analyzed and a carrier in that family was then detected.

CONCLUSION

The polymorphism of DXS102 locus reveals significant difference between Chinese and European populations. DXS102 locus can be used as a promising marker for gene diagnosis in hemophilia B family.

Purification, characterization, and cloning of enamel matrix serine proteinase 1

The maturation of dental enamel succeeds the degradation of organic matrix. Inhibition studies have shown that this degradation is accomplished by a serine-type proteinase. To isolate and characterize cDNA clones encoding this proteinase, we used two degenerate primer approaches to amplify part of the coding region using polymerase chain-reaction (PCR). First, we purified the proteinase from porcine transition-stage enamel matrix and characterized it by partial protein sequencing. The enzyme was isolated from the neutral soluble enamel extract by successive ammonium sulfate precipitations, hydroxyapatite HPLC, reverse-phase HPLC, DEAE ion exchange, and affinity chromatography with a Benzamidine Sepharose 6B column. The intact protein and lysylendopeptidase-generated cleavage products were characterized by amino acid sequence analyses. Degenerate oligonucleotide primers encoding two of the polypeptide sequences were synthesized. In a complementary strategy, degenerate oligonucleotide primers were designed against highly conserved active-site regions of chymotrypsin-like proteinases. Both approaches yielded PCR amplification products that served as probes for screening a porcine enamel organ epithelia-specific cDNA library. The longest full-length clone is 1133 nucleotides and encodes a preproprotein of 254 amino acids. We designate this protein enamel matrix serine proteinase 1 or EMSP1. The active protein has 224 amino acids, an isotope-averaged molecular mass of 24.1 kDa, and an isoelectric point of 6.0. Multiple-tissue Northern analysis indicates that EMSP1 is a tooth-specific protein. Gelatin enzymography shows a dramatic increase in EMSP1 activity in the transition-stage enamel matrix. EMSP1 is most homologous to kallikriens and trypsins.

[Lasting expression of hF IX mediated by myoblasts in mice]

OBJECTIVE

To develop experimentally gene therapy for hemophilia B by using C2C12 cells and C3H mice as models.

METHODS

The retroviral vector containing MCK enhancer and hCMV promoter was constructed and was used to transfect PA317 cells. Then the viral particles were used to transfect C2C12 cells and select the G418r clones,which were further confirmed by Southern, Northern, Western blots. And then the C2C12 cells expressing hF IX protein were injected into C3H mice and hF IX expression in vivo was studied.

RESULTS

The expression level of hF IX in vivo was positively correlated with the number of injected cells, and the in vitro expression level of these cell clones. The expression of hF IX could be enhanced and prolonged by immunosuppressive agents.

CONCLUSION

Allogeneic myoblasts transplantation leads to immunorejection, but repeated injections at a longer intervals could improve the existing rate of transplanted cells. And this might be helpful to gain insight into the myoblast-mediated gene therapy for hemophilia B patients.

[Endometrial cytology in normal postmenopausal women and during hormone replacement therapy]

OBJECTIVE

To explore the possibility of endometrial cyopathologic examination as a method of monitoring endometrium during hormone replacement therapy (HRT) in postmenopausal women.

METHODS

Endometrial cells were taken via tubal aspiration in 60 normal postmenopausal women (non-HRT group) and 41 with HRT for 3-18 months (HRT group). Their morphologic changes were observed and compared by cytopathologist.

RESULTS

Atrophic endometrium was found in 51.7% of the non-HRT group. Its proportion increased with age and the time after menopause. Macrophages were seen in 68.3% of this group. However, in the HRT group the occurrence of atrophic type and macrophage (12.2%, 7.0% respectively) was significantly lower than that in the non HRT group (P < 0.05). Heterogeneity of endometrial cell type was shown both in non-HRT (38.3%) and HRT (65.8%) groups.

CONCLUSIONS

Endometrial cells of postmenopausal women are not always atrophic in appearance. They change significantly during HRT. Endometrial cytological examination may be useful for monitoring during HRT.

[DNA polymorphism analysis by capillary electrophoresis]

A review is given here to describe the principle and methods of gene polymorphism analysis by capillary electrophoresis (CE). DNA length polymorphism and sequence polymorphism are very important phenomena in gene molecular biology. Some practical works of gene length polymorphism analysis and sequence polymorphism analysis are listed. SSCP and HPA methods detecting gene point mutations are demonstrated. Applications of gene polymorphism analysis by CE in clinical, forensic and biological research are also discussed in this paper.

Localization of the domains involved in ligand binding and activation of the glucose-dependent insulinotropic polypeptide receptor

The receptors for the two structurally related insulinotropic hormones Glucose-dependent Insulinotropic Polypeptide (GIP) and Glucagon-Like Peptide-1 (GLP-1) share approximately 40% sequence identity and demonstrate complete specificity for their endogenous ligands, while utilizing similar second messenger pathways. In the current study chimeric GIP-GLP-1 receptors were prepared, and the effect of domain-exchange on ligand binding and adenylyl cyclase activation examined. A chimera (CH-2) consisting of the first 132 amino acids of the external N-terminal (NT) domain bound 125I-GIP with high affinity (27.77 +/- 11.85 nM). However, for receptor coupling to cAMP production it was necessary to extend the NT into the first transmembrane (TM-1) region (CH-3: IC50 = 9.04 +/- 1.07 nM; EC50 = 17.1 +/- 3.5 nM). A chimera which included part of TM-3 (CH-4) demonstrated binding and signalling (IC50 = 8.33 +/- 0.14 nM; EC50 = 467.5 +/- 173.6 pM) similar to the wild type receptor (IC50 = 1.33 +/- 0.19 nM; EC50 = 497.9 +/- 211.7 pM). Surprisingly constructs CH-2 and CH-3, while devoid of detectable 125I-GLP-1 binding, were capable of eliciting GLP-1-specific cAMP production (EC50s CH-2 = 81.4 +/- 19.6 nM; CH-3 = 5.99 +/- 0.68 nM) suggesting that receptor activation is not completely dependent on high affinity receptor binding. These data clearly demonstrate that the NT domain of the GIP receptor acts as the ligand-specific binding domain and that the first transmembrane domain is important for receptor activation.

Association between lactation length and sow reproductive performance and longevity

OBJECTIVE

To determine whether lactation length was associated with reproductive performance or longevity of sows.

DESIGN

Cohort study.

SAMPLE POPULATION

Data collected between 1986 and 1992 for sows in 15 breeding herds in Minnesota and Iowa.

PROCEDURE

Sows were grouped into 4 genetic line categories according to their sources and 6 parity categories (1, 2, 3, 4, 5 or 6, and > or = 7). Multivariate regression analysis of reproductive performance was conducted, using the general linear model procedure Logistic regression was conducted with a dichotomous response variable for sow longevity (ie, removal from or retention in the herds). Odds ratios were obtained from estimated coefficients of the regression.

RESULTS

Herd, genetic line, parity, year, month, and lactation length were significant in statistical models for litter (eg, number of live pigs/litter) and interval (eg, weaning-to-mating interval) traits. Interactions between lactation length and year, lactation length and genetic line, lactation length and parity, and lactation length and genetic line and parity were also significant. Sows removed from herds had a significantly shorter lactation length than did sows of the same parity that were retained in the herds. Sows that had shorter lactation lengths were at higher risk of being removed from the herds than were those that had longer lactation lengths.

CLINICAL IMPLICATIONS

Lactation length is associated with reproductive performance and longevity, but genetic line and parity play a role as well. Thus, attention should be paid to genetic lines and parity of sows in the herd when implementing an early weaning production practice.

[The study of DSX-I type microcomputer autometic control injector system]

This paper studies the propulsive force of injector system controlled by 8031 single-chip microcomputer for Medical use By using one 8031 single-chip microcomputer as a microprocessor, the minimal autometic control system is constructed, which turns real-time control into reality. This product is a modern appliance used in diagnostic imaging medicine, in design of which the advanced instrument and electrical machinery are integrated into a unified structure. The clinic data demonstrate that the contrast medium can be injected to patients with rapidly and evenly. Dynamic CT Scanning can be intensified at any site of the body. x-ray dose exposed and lobour intensity to the operator can be decreased greatly, raise working efficiency.

Molecular cloning and mRNA tissue distribution of a novel matrix metalloproteinase isolated from porcine enamel organ

A cDNA encoding a novel matrix metalloproteinase (MMP) was isolated from a porcine enamel organ-specific cDNA library. Multiple tissue northern blot analysis revealed the presence of two mRNA transcripts which were expressed only in the enamel organ. The transcripts were 1968 bp or 3420 bp in length and resulted from the utilization of alternative polyadenylation sites. The open reading frame of the cloned mRNA encodes a protein composed of 483 amino acids. The MMP has a predicted molecular mass of 54.1 kDa, which is similar to that of the stromelysins or collagenases, although it is not a member of either of these two classes of MMPs. A motif analysis revealed that the cloned MMP does not contain a consensus hemopexin-like domain because it lacks a critical tryptophan and proline residue at the appropriate positions. Since the cloned MMP is a new member of the MMP gene family and its expression appears limited to the enamel organ, we have named it enamelysin.

Breed differences in boar taint: relationship between tissue levels boar taint compounds and sensory analysis of taint

A total of 228 intact male pigs form Duroc, Hampshire, Landrace, and Yorkshire breeds were used in the experiment. Samples of salivary gland and backfat were collected at slaughter for colorimetric assay of salivary and fat 16-androstene levels and fat skatole levels. Fat levels also were tested by a sensory panel using an R-index technique for detecting the presence of boar taint. The proportion of tainted carcasses determined by the sensory panel was 5.0% for androstenone and 11.4% for skatole, with a combined total of 15.0% tainted from either source. Sensory analysis of taint showed a lower proportion (P < .05) of tainted carcasses in Hampshire, with no difference in taint across the other three breeds. Analysis of taint compounds indicated that overall 14.5% of pigs had salivary gland 16-androstene levels and 20.9% had fat 16-androstene levels above acceptable limits. There was a higher (P < .05) proportion of Duroc pigs above the threshold levels for 16-androstenes in both salivary gland and fat. Landrace pigs had the lowest (P < .05) average tissue concentrations of steroids and skatole. Across breeds, only 1.8% of pigs had fat skatole concentrations above .25 ppm, which has been suggested as threshold levels of skatole for taint. The canonical correlation coefficient between fat compound levels and the R-indices of fat 16-androstenes and skatole was .40 (P < .001). Our results indicate breed differences in tissue levels of taint compounds and in taint assessed by a sensory panel. Levels of 16-androstene steroids were highly associated with taint, but more pigs had measured levels above the threshold than those identified as tainted by sensory analysis. Levels of fat skatole were low overall and did not account for all the pigs judged as tainted from skatole by sensory analysis.

[Transurethral noncontact laser ablation of the large prostate]

42 cases of the large benign hypertrophy of the prostate were treated by transurethral noncontact laser ablation. The results of the patients followed up no less than six months and treatment were reported. The technique of the procedure and its related problems were described and our experience was presented. If we use the technique of the procedure skill fully, noncontact laser ablation of large benign hypertrophy of the prostate is safe and effective.

Particulate air pollution and respiratory disease in Anchorage, Alaska

This paper examines the associations between average daily particulate matter less than 10 microns in diameter (PM10) and temperature with daily outpatient visits for respiratory disease including asthma, bronchitis, and upper respiratory illness in Anchorage, Alaska, where there are few industrial sources of air pollution. In Anchorage, PM10 is composed primarily of earth crustal material and volcanic ash. Carbon monoxide is measured only during the winter months. The number of outpatients visits for respiratory diagnoses during the period 1 May 1992 to 1 March 1994 were derived from medical insurance claims for state and municipal employees and their dependents covered by Aetna insurance. The data were filtered to reduce seasonal trends and serial autocorrelation and adjusted for day of the week. The results show that an increase of 10 micrograms/m3 in PM10 resulted in a 3-6% increase in visits for asthma and a 1-3% increase in visits for upper respiratory diseases. Winter CO concentrations were significantly associated with bronchitis and upper respiratory illness, but not with asthma. Winter CO was highly correlated with automobile exhaust emissions. These findings are consistent with the results of previous studies of particulate pollution in other urban areas and provide evidence that the coarse fraction of PM10 may affect the health of working people.

Intercommunity differences in acid aerosol (H+)/sulfate (SO4(2-) ratios

Exposures to acid aerosols have been associated with acute and chronic health effects. Beginning in 1988, extensive monitoring of acid aerosols (H+), sulfates (SO4(2-)), and ammonia (NH3) was conducted in 24 communities in the United States and Canada in order to characterize the seasonal and daily variations of these pollutants. More recently, in 1992 and 1993, summer monitoring of the same pollutants was conducted by Harvard researchers at multiple locations in Philadelphia, Pennsylvania to examine the factors causing spatial variation in the acidity levels in the greater metropolitan Philadelphia area. Earlier, a similar study also was conducted by Harvard in a more rural community, State College, Ohio, providing data on acidity, sulfate, and ammonia levels. In addition to these studies, New York University researchers have gathered substantial data on aerosol acidity, sulfates, and NH3 levels from sites in the New York City metropolitan region, Albany, Buffalo, and the Toronto metropolitan region between 1988 and 1992. This paper examines the relationships among H+, SO4(2-), ozone, and population density using summer measurements from sites in 24 cities across the United States and Canada, as well as Philadelphia, State College, the New York City region, Buffalo, and Albany. While past studies have consistently shown that H+ and SO4(2-) are correlated over time at sites in eastern North America, the results of our analysis show that spatial variations in the ratios of mean acid-to-sulfate levels also can be predicted satisfactorily with the use of either a linear or a quadratic model, once variations in population density are addressed (R2 = 0.6). These models may be useful in retrospective epidemiological investigations of acid aerosol exposures and health effects, using widely available sulfate measurements and data on local population size.

Personal exposure to airborne particles and metals: results from the Particle TEAM study in Riverside, California

The PTEAM Study was the first large-scale probability-based study of personal exposure to particles. Sponsored by the U.S. Environmental Protection Agency (EPA) and the Air Resources Board of California, it was carried out by the Research Triangle Institute (RTI) and the Harvard University School of Public Health (HSPH). HSPH designed and constructed a 4-lpm, battery-operated personal monitor for inhalable particles (PM10) that could be worn comfortably for up to 14 hours by persons from 10 to 70 years old. The monitor was worn for two consecutive 12-hour periods (day and night) during the fall of 1990 by 178 participants representing 139,000 nonsmoking residents of Riverside, California. Nearly identical monitors were employed to collect concurrent indoor and outdoor samples. The monitors were equipped with a different sampling nozzle to collect fine particles (PM2.5). Population-weighted daytime personal PM10 exposures averaged 150 +/- 9 (SE) micrograms/m3, compared to concurrent indoor and outdoor concentrations of 95 +/- 6 micrograms/m3. This suggested the existence of excess mass near the person, a "personal cloud" that appeared related to personal activities. Fourteen of 15 prevalent elements also were evaluated in the personal samples. The two major indoor sources of indoor particles were smoking and cooking; even in these homes, however, more than half of the indoor particles came from outdoors, and a substantial portion of the indoor particles were of undetermined indoor origin. Outdoor concentrations near the homes were well correlated with outdoor concentrations at the central site, supporting the idea of using the central site as an indicator of of ambient concentrations over a wider area. Indoor concentrations were only weakly correlated with outdoor concentrations, however, and personal exposures were even more poorly correlated with outdoor concentrations. Elemental profiles were obtained for environmental tobacco smoke (ETS) (major contributions from potassium and chlorine) and cooking emissions (aluminum, iron, calcium, and chlorine). These profiles can be used in future source apportionment studies.

Determination of polyamines in serum by high-performance capillary zone electrophoresis with indirect ultraviolet detection

A method for determining polyamines in serum by capillary zone electrophoresis (CZE) with indirect ultraviolet detection was established. The concentrations of polyamines in the sera of six healthy adults were determined and the results were in accordance with those obtained previously by high-performance liquid chromatography (HPLC). However, the CZE method is superior to HPLC in that it has high sensitivity, small sample consumption and easy sample pretreatment.

The unusual 5' splicing border GC is used in myrosinase genes of the Brassicaceae

Myrosinase (thioglucosidase glucohydrolase; EC 3.2.3.1) is a group of isoenzymes in the Brassicaceae, which hydrolyze glucosinolates. Genes encoding myrosinase contain 12 exons and 11 introns. Sequence comparison of two myrosinase genes from Arabidopsis thaliana, TGG1 and TGG2, with the corresponding cDNA from leaves, showed preferential use of a GC dinucleotide as the 5' splicing border in intron 1 instead of an adjacent GT dinucleotide four bp further 3'. This 5' GC splice site is conserved in all seven myrosinase genes characterized from three different species. Likewise, in the 3' region of intron 1 two AG dinucleotides are located seven bp apart. Only the most 5' of these dinucleotides was found to be used in splicing. Sequence analyses of TGG1 cDNA isolated from seeds, siliques and vegetative tissue using reverse transcription PCR showed that the splicing pattern of this intron is identical in these tissues for TGG1. The GT and the most 3' AG dinucleotides mentioned above have been assumed to be the intron borders of intron 1 in several myrosinase genes. The present investigation shows that this assumption is not correct.

A population-based exposure model for benzene

A model of daily-average inhalation exposures and total-absorbed doses of benzene to members of large populations was developed as part of a series of multimedia exposure and absorbed dose models. The benzene exposure and dose model is based upon probabilistic rather than sequential simulation of time-activity patterns, a simpler approach to modeling personal benzene exposures than other existing models. An important innovation of the benzene model is the incorporation of an anthropometric module for generating correlated exposure factors used to estimate absorbed doses occurring from inhalation, ingestion, and dermal absorption of benzene. A preliminary validation exercise indicates that the benzene model produces reasonable estimates of the distribution of benzene personal air concentrations expected for a large population. Uncertainty about specific percentiles of the predicted distributions of personal air concentrations was found to be dominated by uncertainty about microenvironmental benzene concentrations rather than time-activity patterns, and uncertainty about total absorbed doses was dominated by a lack of knowledge about the true absorption coefficient for benzene in the lung rather than knowledge gaps about microenvironmental concentrations or intake rates. The results of this modeling effort have implications for environmental control decisions, including evaluation of source control options, characterization of population and individual risk, and allocation of resources for future studies.

Regulation of human clotting factor IX cDNA expression in transgenic mice

To study the expression of human clotting factor IX cDNA in transgenic mice, which is an essential work on gene therapy for hemophilia B, 3 recombinant constructions containing different lengths of human clotting factor IX cDNA have been introduced into the cultured cells. All of the recombinant constructions were found to be expressed well in vitro. They were then microinjected into the male pronuclei of the fertilized mouse eggs respectively for generating transgenic mice. Unfortunately, none of them was expressed in any transgenic mice. These results show that the expression of the human clotting factor IX cDNA in the transgenic mice can be determined by cis regulatory element(s). As compared with the results from other related works, it is suggested that the cis regulatory element(s) is resided in the 5'-end non-coding region.

Construction and high expression of retroviral vector with human clotting factor IX cDNA in vitro

The construction of the high titer and highly expressed safety retroviral vector carrying human clotting factor IX cDNA is reported. Retroviral vectors LNCIX, LIXSN and LCIXSN, driven by hCMV, LTR and hCMV combined with LTR promoter respectively, were constructed, based on the retroviral vector LNL6, and transferred into packaging cell line PA317 with electroporation. Human clotting factor IX was detected in the cultured cells transduced with LNCIX and LIXSN but not in the cells transduced with LCIXSN. The viral titer of PA317/LNCIX was 800,000 CFU per mL. With ELISA detection, it was found that the cells transduced with this vector can express human clotting factor IX at the level of 3.3 micrograms per 10(6) cells in 24 h in human fibrosarcoma cells HT-1080 and 2.5 micrograms per 10(6) cells in 24 h in hemophilia B patients' skin fibroblast HSF cells, and more than 80% of them were biologically active. The viral titer and expression of human FIX were increased, and the construction of retroviral vector backbone was improved and the safety was guaranteed as compared to those vectors used previously. These vectors may produce a sufficient quantity of factor IX proteins to cause the phenotypic modification for hemophilia B patients.

Human thioredoxin reductase directly reduces lipid hydroperoxides by NADPH and selenocystine strongly stimulates the reaction via catalytically generated selenols

Human placenta thioredoxin reductase (HP-TR) in the presence of NADPH-catalyzed reduction of (15S)-hydroperoxy-(5Z),(8Z),11(Z),13(E)-eicosatetraenoic acid ((15S)-HPETE) into the corresponding alcohol ((15S)-HETE). Incubation of 50 nM HP-TR and 0.5 mM NADPH with 300 microM 15-HPETE for 5 min resulted in formation of 16.5 microM 15-HETE. After 60 min, 74.7 microM 15-HPETE was reduced. The rate of the reduction of 15-HPETE by the HP-TR/NADPH peroxidase system was increased 8-fold by the presence of 2.5 microM selenocystine, a diselenide amino acid. In this case, 15-HPETE was catalytically reduced by the selenol amino acid, selenocysteine, generated from the diselenide by the HP-TR/NADPH system. To a smaller extent, selenodiglutathione or human thioredoxin also potentiated the reduction of 15-HPETE by HP-TR. Hydrogen peroxide and 15-HPETE were reduced at approximately the same rate by HP-TR, thioredoxin, and selenocystine. In contrast, t-butyl hydroperoxide was reduced at a 10-fold lower rate. Our data suggest two novel pathways for the reduction and detoxification of lipid hydroperoxides, hydrogen peroxide, and organic hydroperoxides, i.e. the human thioredoxin reductase-dependent pathway and a coupled reduction in the presence of selenols or selenide resulting from the reduction of selenocystine or selenodiglutathione.

Characterization of bronchodilator effects and fate of S-nitrosothiols in the isolated perfused and ventilated guinea pig lung

In this study the effects of S-nitrosothiols, in particular S-nitrosoglutathione (GSNO), were evaluated with regard to their bronchodilating properties, both after infusion via the pulmonary circulation and after inhalation, in the isolated perfused and ventilated guinea pig lung. Infused GSNO induced bronchorelaxation of lungs that were precontracted with methacholine. During a 15-min period of single-passage perfusion with GSNO (10 microM), maximally 10% was taken up and/or degraded by the lung. A spontaneous breakdown of GSNO in the perfusion buffer was also observed, which was partially accompanied by the formation of nitrite. Low levels of nitric oxide (NO) were detected in the perfusion buffer when GSNO was present. This was due to the presence of contaminating transition metals, because EDTA and 2,2'-dipyridyl largely reduced the formation of NO. The NO-scavenging agents oxyhemoglobin and 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide abolished levels of NO in the buffer but did not abolish GSNO-induced bronchodilation. The effects of infused GSNO are therefore attributed to an action of the intact S-nitrosothiol and not to NO released from GSNO in the perfusion buffer. Similarly, perfusion with S-nitrosated glutathione isopropyl ester, cysteinyl glycine, N-acetyl-L-cysteine or N-acetyl-D,L-penicillamine, but not with nitrosated bovine serum albumin or sodium nitrite, was found to induce bronchodilation. Inhalation of nebulized GSNO induced bronchodilation of methacholine-precontracted lungs with a rapid onset of action, although it was a less potent bronchodilator than salbutamol. The results show that infused or inhaled S-nitrosothiols have bronchodilating properties in the isolated perfused and ventilated guinea pig lung.

The myrosinase gene family in Arabidopsis thaliana: gene organization, expression and evolution

Myrosinase (thioglucoside glucohydrolase, EC 3.2.3.1.) is in Brassicaceae species such as Brassica napus and Sinapis alba encoded by two differentially expressed gene families, MA and MB, consisting of about 4 and 10 genes, respectively. Southern blot analysis showed that Arabidopsis thaliana contains three myrosinase genes. These genes were isolated from a genomic library and two of them, TGG1 and TGG2, were sequenced. They were found to be located in an inverted mode with their 3' ends 4.4 kb apart. Their organization was highly conserved with 12 exons and 11 short introns. Comparison of nucleotide sequences of TGG1 and TGG2 exons revealed an overall 75% similarity. In contrast, the overall nucleotide sequence similarity in introns was only 42%. In intron 1 the unusual 5' splice border GC was used. Phylogenetic analyses using both distance matrix and parsimony programs suggested that the Arabidopsis genes could not be grouped with either MA or MB genes. Consequently, these two gene families arose only after Arabidopsis had diverged from the other Brassicaceae species. In situ hybridization experiments showed that TGG1 and TGG2 expressing cells are present in leaf, sepal, petal, and gynoecium. In developing seeds, a few cells reacting with the TGG1 probe, but not with the TGG2 probe, were found indicating a partly different expression of these genes.

[Effect of low dose rhTNF-alpha on immune function of lymphocytes in burned rats]

SD rats (200-230 g body weight) were randomly divided into three groups: (1) sham burn; (2) burn; (3) burn plus rhTNF-alpha. Third degree burn of 30% TBSA on the trunk was produced in groups 2 and 3. Intravenous rhTNF-alpha(10 micrograms/kg) was administered 6 hours postburn and once daily thereafter for 5 days in group 3. At 5 days postburn, splenic lymphocytes obtained from all the animals were used for the determination of distribution of T lymphocyte subsets with flowcytic analysis and activity of IL-2(Gills method). The results indicated that low dose rhTNF-alpha in vivo could improve distribution of splenic T lymphocyte subsets in burned rats by increasing the numbers of W3/25(Th) and decreasing the number of OX-8(Ts), and the ratio of W3/25/OX-8 was raised. In vitro the proliferation response of T lymphocytes to ConA was enhanced and the activity of IL-2 was increased by 108%, 149% and 168%, respectively, in group 3 compared with that in group 2. However, a dose-dependent effect, in that a small dose (< or = 10 ng/2.5 x 10(6) cells) of rhTNF-alpha improved the immune function of T lymphocytes, while a higher dose inhibited T lymphocyte immune function. These findings showed that rhTNF-alpha improved not only the distribution of T lymphocyte subsets but also their immune activity.

The thioredoxin and glutaredoxin systems are efficient electron donors to human plasma glutathione peroxidase

Human plasma glutathione peroxidase (GSH-Px) is a distinct extracellular selenoenzyme that detoxifies hydroperoxides when used with GSH in high (mM) non-physiological concentrations. We have discovered that NADPH and human thioredoxin reductase (TR) by itself or with thioredoxin (Trx) are efficient electron donors to this human plasma peroxidase. Incubation of 0.05 microM TR with 0.25 microM GSH-Px, in a system free from GSH, resulted in reduction of t-butyl hydroperoxide. Addition of Trx, 2.5 and 5 microM, respectively, further increased the rate of the reaction. These data were obtained using an assay measuring the oxidation of NADPH. A direct assay demonstrated the formation of cumyl alcohol from cumene hydroperoxide in this GSH-independent peroxidase reaction. Incubation of 0.25 microM GSH-Px with a low concentration of GSH (10 microM), representing the upper level in plasma, plus excess glutathione reductase and NADPH did not result in any reduction of t-butyl hydroperoxide. However, after addition of 2.5 microM human glutaredoxin, a linear peroxidase reaction started. The results suggest that extracellular TR, Trx, or glutaredoxin are reductants for the selenium-dependent peroxidase rather than GSH.