Automated knowledge extraction from the UMLS

This paper presents our work in extracting disease-chemical relationship knowledge from the UMLS Co-occurrence table (MRCOC) using an automated method. We evaluated the quality of the knowledge from UMLS MRCOC by comparing it with knowledge from other sources: For disease-lab chemical relationships, knowledge was obtained from a decision support system (DXplain) and our own knowledge base of medical terminology (MED) through automated processes. For disease-drug chemical relationships, knowledge was manually acquired from the medical literature. Evaluations showed that the UMLS MRCOC knowledge has good sensitivity, especially regarding disease-drug relationships. We are using this knowledge to produce disease-specific views of patients' electronic patient record.

Calibration inference based on multiple runs of an immunoassay

Several authors have documented the poor performance of usual large-sample, individual calibration confidence intervals based on a single run of an immunoassay. Inaccuracy of these intervals may be attributed to the paucity of information on model parameters available in a single run. Methods for combining information from multiple runs to estimate assay response variance parameters and to refine characterization of the standard curve for the current run via empirical Bayes techniques have been proposed. We investigate formally the utility of these techniques for improving the quality of routine individual calibration inference.

Testing homogeneity of intra-run variance parameters in immunoassay

A common assumption in the analysis of immunoassay data is a similar pattern of within-run variation across runs of the assays. One makes this assumption without formal investigation of its validity, despite the widely acknowledged fact that accurate understanding of intra-run variation is critical to reliable calibration inference. We propose a simple procedure for a formal test of the assumption of the homogeneity of parameters that characterize intra-run variation based on representation of standard curve data from multiple assay runs by a non-linear mixed effects model. We examine the performance of the procedure and investigate the robustness of calibration inference to incorrect assumptions about the pattern of intra-run variation.

Inhibition of epidermal growth factor receptor gene expression and function decreases proliferation of head and neck squamous carcinoma but not normal mucosal epithelial cells

Previous reports have shown that fresh tissues and cell lines from patients with squamous cell carcinoma of the head and neck (SCCHN) overexpress transforming growth factor alpha (TGF-alpha) and its receptor, the epidermal growth factor receptor (EGFR) at both the mRNA and protein levels. Protein localization studies confirm that TGF-alpha and EGFR are produced by the same epithelial cells in tissues from head and neck cancer patients further supporting an autocrine growth pathway. Using three strategies, we examined the hypothesis that downmodulation of EGFR would reduce the proliferation of SCCHN cells. We targeted EGFR mRNA using antisense oligonucleotides and the mature EGFR protein at two sites, the ligand-binding domain and the kinase domain, and determined the effects of this targeting on SCCHN proliferation. Treatment of several SCCHN cell lines with a pair of antisense oligodeoxynucleotides directed against the translation start site and first intron-exon splice junction of the human EGFR gene resulted in decreased EGFR protein production and inhibited growth by 86% compared to a 13% reduction in cells treated with sense oligonucleotides (P=0.03). Growth inhibition was specific for carcinoma cells since the same EGFR antisense oligonucleotides had no effect on the proliferation of normal mucosa cells harvested from non-cancer patients. Two monoclonal antibodies which block ligand binding to EGFR (MAbs 425 and 528) inhibited the growth of several SCCHN cell lines by up to 97% which suggests that EGFR is participating in an autocrine pathway in SCCHN that is, at least in part, external. An EGFR-specific tyrosine kinase inhibitor (PD 153035) was found to inhibit EGFR phosphorylation in SCCHN cell lines and to reduce growth by 68% although it had no effect on the growth rate of normal mucosal epithelial cells. These experiments indicate that EGFR gene expression and function is critical for SCCHN cell growth but not for growth of normal mucosa cells and therefore may serve as a tumor-specific target for preventive and therapeutic strategies in head and neck cancer.

Contribution of the C-terminal tail of U1A RBD1 to RNA recognition and protein stability

The N-terminal RNA binding domain (RBD1) of the human U1A protein interacts specifically with a short RNA hairpin containing the U1 snRNA stem/loop II sequence. Previous RNA binding studies have suggested that the C-terminal tail of RBD1 contributes to RNA recognition in addition to interactions on the beta-sheet surface of the protein. To evaluate the contributions of these C-terminal residues in RBD1 to RNA binding affinity and specificity, as well as to study the thermodynamic stability of RBDs, a number of RBD1 mutants with truncated tails, with single amino acid substitutions, and with both a truncation and an amino acid substitution, have been constructed. The thermodynamic stabilities of these mutants have been measured and compared by GdnHCI unfolding experiments. The RNA binding affinity and specificity of these mutant proteins have been assessed by measuring the binding of each protein to the wild-type RNA hairpin and to selected RNA mutants with nucleotide substitutions in the RNA loop. The results demonstrate first that, although the C-terminal tail of RBD1 makes significant contributions to RNA binding affinity, it is not required for RNA binding, and second, its contributions to binding specificity are mediated only through selected nucleotides in the RNA loop, for in the absence of the tail, the protein continues to use other nucleotides to discriminate among RNAs. In these truncated proteins, the secondary structure intrinsic to the C-terminal tail is absent, yet their affinity and discrimination for RNAs are not lost. Thus, a structured tail is not required for RNA recognition.

[10-year epidemiological study on rheumatic diseases in Shantou area]

22,049 adults were surveyed in a ten-year epidemiological study. The frequency of common rheumatic symptoms in Shantou population was much lower than that in northern China. The prevalence of ankylosing spondylitis, rheumatoid arthritis, osteoarthritis, osteoporosis and gout was 0.20%-0.32%, 0.20%-0.26%, 8.3%-10.8%, 12.4% and 0.15%-0.17% respectively. The frequency of HLA-B27 was 4.1% among general population and 90.6% in ankylosing spondylitis. The most commonly involved sites of osteoarthritis were lumbar spine, neck, and knee; but hands and hip were rarely involved. 85% subjects under investigation were found to be short of calcium intake. The differences between the north and the south of China in the prevalence of rheumatic symptoms may be related to the diversities in consciousness of seeking medical advice, reduction of bone content, climate and ergonomics.

Supporting infobuttons with terminological knowledge

We have developed several prototype applications which integrate clinical systems with on-line information resources by using patient data to drive queries in response to user information needs. We refer to these collectively as infobuttons because they are evoked with a minimum of keyboard entry. We make use of knowledge in our terminology, the Medical Entities Dictionary (MED) to assist with the selection of appropriate queries and resources, as well as the translation of patient data to forms recognized by the resources. This paper describes the kinds of knowledge in the MED, including literal attributes, hierarchical links and other semantic links, and how this knowledge is used in system integration.

Linking a clinical system to heterogeneous information resources

We present a model for providing clinical information system (CIS) users with quick access to high quality information resources. We have developed a chest X-ray information button application which is attached to the chest X-ray reports in the CIS at the Columbia Presbyterian Medical Center. The application generates questions based on clinical information, user interest, generic question templates, and resource availability. It then provides answers to the questions through integrated access to heterogeneous information resources including the CIS itself and publicly accessible Web resources.

[Combustion under microgravity and technique of fire prevention and suppression in space cabin]

This is a brief review on microgravity combustion, along with the discussion of the fundamental characteristics of combustion and fire processes under microgravity. Recent research activities in microgravity combustion and space fire prevention were emphasized. In addition, the potential use of flame-inhibiting atmospheres in the space cabin was introduced. The technique of fire detection and extinguishment in spacecraft environments was also discussed.

Exact solution to the electric field of the double-sided electrode structure in a lead lanthanum zirconated titanate transverse electro-optic modulator

Analytical expressions for the electric field and the capacitance of a double-sided electrode structure are derived by the conformal-mapping method. A clear picture of the electric field is given for an analysis of the quadratic electro-optic effect in a lead lanthanum zirconated titanate transverse modulator. The excess birefringence in the region near the edge of the electrodes causes a reduction of the nonuniformity in the intensity modulation of a double-sided electrode structure compared with that of single-sided electrodes; this reduction is calculated.

Measuring self-efficacy in people with multiple sclerosis: a validation study

OBJECTIVE

To assess the psychometric properties of a measure of self-efficacy in people with multiple sclerosis (MS).

DESIGN

Cross-sectional study by mail with retest.

SETTING

MS Clinic registry of a large Boston teaching hospital .

PATIENTS

141 MS patients representing a broad range of disability.

MAIN OUTCOME MEASURES

The MS Self-Efficacy Scale (MSSE), the Expanded Disability Status Scale, the Sickness Impact Profile, and the mastery subscale of the Ryff Happiness Scale.

RESULTS

The MSSE has high internal consistency and test-retest reliability, both for the overall scale and for the SE Function and SE Control subscales. Results of convergent and divergent validity analyses suggest that the scale is both sensitive and specific.

CONCLUSIONS

We conclude that MSSE is appropriate for assessing self-efficacy in the MS population.

Psychosocial correlates of fatigue in multiple sclerosis

OBJECTIVE

To explore: (1) the interrelation among the neuropsychological, psychological, and psychosocial factors and fatigue as measured by the Multidimensional Assessment of Fatigue scale, and (2) the impact of fatigue on role performance.

DESIGN

Clinical interview with neuropsychological testing and cross-sectional study by mail.

SETTING

Multiple sclerosis (MS) clinic registry of a large Boston teaching hospital.

PATIENTS

139 MS patients representing a broad range of disability.

MAIN OUTCOME MEASURES

The Multidimensional Assessment of Fatigue (MAF) scale, the Extended Disability Status Scale, the Sickness Impact Profile, Rao cognitive battery, the Trailmaking Test, depression, anxiety, and social activity limitations subscales from the Arthritis Impact Measurement Scales, and the Ryff Happiness Scale.

RESULTS

Stepwise multiple regression analyses revealed that having a low sense of environmental mastery was the best psychosocial predictor of both global fatigue and fatigue-related distress, after adjusting for sociodemographic and medical factors. Further, people who reported being more depressed tended to report more severe fatigue. Neuropsychological performance was not associated with fatigue. Fatigue was found to limit social, work, and overall role performance, but not physical role performance.

CONCLUSIONS

People who feel that they can choose or create environments suitable to their psychic or physical conditions report less global fatigue and less fatigue-related distress, and fatigue can have an important impact on role performance. The implications of these findings for designing fatigue management interventions are discussed.

Retinoic acid normalizes the increased gene transcription rate of TGF-alpha and EGFR in head and neck cancer cell lines

Retinoic acid (RA) has been shown to be effective in eradicating premalignant lesions and preventing second primary malignancies in patients cured of squamous cell carcinoma of the head and neck (SCCHN) in clinical trials. The basis for this effect is unclear. We have previously demonstrated that messenger RNA from tumor growth factor-alpha (TGF-alpha) and its receptor, the epidermal growth factor (EGFR), is unregulated in tumors and histologically normal mucosal samples from patients with SCCHN compared with control normal mucosa from patients without cancer, implicating this ligand-receptor pair in an autocrine growth pathway early in the molecular pathogenesis of this disease. In this report, we examined the hypothesis that the action of RA on the mucosa of the upper aerodigestive tract is mediated via downregulation of steady-state TGF-alpha and/or EGFR mRNA levels. Following exposure to all-trans-RA, a series of SCCHN cell lines demonstrated a 35.4% reduction in TGF-alpha mRNA expression (P = 0.022) and 58.5% reduction in EGFR mRNA (P = 0.0027). Nuclear run-on analysis indicated that the RA-mediated reduction of TGF-alpha and EGFR steady-state mRNA levels was a result of decreased gene transcription. These results suggest that the clinical effects of RA in SCCHN patients may be due to a downmodulation of TGF-alpha and EGFR mRNA production.

The N-terminal domain of TFIIB from Pyrococcus furiosus forms a zinc ribbon

The three-dimensional structure of the N-terminal domain of an archaeal TFIIB, which has high sequence homology with eucaryal analogues, is strikingly similar to that of the C-terminal zinc ribbon of the eucaryal transcription elongation factor TFIIB.

Mapping medical vocabularies to the Unified Medical Language System

This paper presents our work in automated mapping of medical vocabularies to the National Library of Medicine's Unified Medical Language System (UMLS). We used the UMLS Knowledge Source (KS) tool to map terms from several sources to UMLS Metathesaurus concepts. We compared performance of the KS tools with our own Minimal Representable Units Method (MRUM). The KS tools were able to map terms from 13% to 54% of the time, depending on the term set and the KS options used. Our MRUM method mapped between 96% and 99% of the terms. Based on our experience, we believe that questions remain about the best method by which the UMLS can be used to achieve automated term translation.

Insect-resistant tobacco plants expressing insect-specific neurotoxin AaIT

The recombinant plant expression vector pNGY-2 with designed and synthesized AaIT gene had been constructed. The AaIT gene was fused behind the sequence of TMV and inserted into expression vector under the control of two linked 35s promoters. The recombinant plasmid pNGY-2 was transferred into tobacco NC89 by agrobacterium-mediated transfer system. The GUS activity analysis and Southern blotting of regenerated plants indicated that AaIT gene had been integrated into tobacco genome. Insect bioassays showed that some transgenic plants had notable insect-resistant activity.

Glycoconjugates and keratin 18 define subsets of taste cells

Sections of neonatal, normal adult and denervated adult rat tongue were examined with lectin histochemistry. Attention was focused upon intragemmal cells (cells within the taste bud) and the surrounding perigemmal cells. Informative staining patterns were observed with four of 12 lectins: Ulex europaeus (UEA-I), Bauhinia purpurea (BPA), Helix pomatia (HPA) and Lotus tetragonolobus (LTA) agglutinins. In normal adult tongues, BPA bound to those lingual epithelial cells lacking contact with the basal lamina. After they formed, vallate taste buds were laterally surrounded by distinctive BPA-positive cells. HPA reacted selectively with 28% and LTA with 23% of the intragemmal cells in vallate/foliate taste buds. In double-stained taste buds there was a statistically significant overlap of LTA-positive cells and keratin 18-positive cells. The overlap between HPA binding and keratin 18 was more marked: double-stained cells comprized 67% of all stained cells. During taste bud development in neonates keratin 18 synthesis preceded HPA binding. In contrast, during the replacement of adult taste cells, keratin 18 synthesis and HPA binding were generally concurrent. Keratin 18 and HPA probably identify the same subset of older taste receptor cells. HPA may bind to glycoconjugates on the surface of keratin 18-positive cells. In denervated adult tongue the loss of all UEA-I-positive or BPA-positive perigemmal cells suggests that perigemmal as well as intragemmal cells are nerve-dependent.

[Plasma nitric oxide in patients with renal transplants]

The plasma nitric oxide (NO) in 32 patients with renal allografts was observed before transplantation and in the early period of three months after transplantation. Endothelin (ET), cyclosporin A blood concentration, Creatinine (Cr), blood urea nitrogen (BUN) were measured simultaneously. The results showed that plasma NO level (24.01 +/- 1.15 mumol/L) before transplantation was significantly higher than that after transplantation. There was significant correlation between plasma NO level and ET, Cr, BUN and blood pressure. We consider that plasma NO concentration may reflect the function of renal transplant and play an important role in early renal injury after kidney transplantation.

Keratin 18 is associated with a subset of older taste cells in the rat

All or nearly all intragemmal (elongated) cells of rat taste buds were immunopositive for keratins 7, 8, and 19. In contrast, keratin 18 was detected in 19 +/- 5 cells per taste bud (mean +/- sd), or about 25% of the intragemmal cells. During taste bud development keratins 7, 8, and 19 were evident initially in polygonal cells and later in elongated taste cells. Keratin 8 appeared in vallate taste cells at P0 (postnatal day 0), followed by keratins 7 and 19 at P1, and keratin 18 at P2-P3. Keratin 18 was always limited to elongated cells. The assemblage of elongated taste cells comprising a taste bud began with a single elongated cell, rather than with the synchronous elongation of a cluster of cells. Developmental errors were observed at P2-P3, e.g., some vallate taste cells had a misoriented axis. In order to study the pace of keratin differentiation during cell turnover we injected bromodeoxyuridine (BrdU) into adult rats to monitor taste cell age. Keratin-19-positive intragemmal cells differentiated within 1 day. In contrast, keratin 18 was first detected in cells aged 3 days. Hence, both in taste cell development and replacement, keratin 18 was restricted to the older cells; it was the last taste cell keratin to become expressed during differentiation.

An apolipoprotein CIII marker associated with hypertriglyceridemia in Caucasians also confers increased risk in a west Japanese population

Polymorphisms and haplotypes at the adjacent apolipoprotein (apo) AI and CIII gene loci were investigated in 61 Japanese patients with triglycerides greater than 350 mg/dl and in 66 unrelated normolipidemic subjects. The polymorphic sites were the SstI site in the apoCIII 3' untranslated region, whose presence has previously been shown to be associated with hypertriglyceridemia (HTG) in Caucasians, and the MspI site in the third intron of the apoAI gene. The frequencies of the SstI minor allele (S2) were 0.48 in HTG patients and 0.25 in normolipidemic subjects (P < 0.00015). The frequencies of the MspI minor allele (M2) were 0.61 in HTG patients and 0.33 in normolipidemic subjects (P < 0.00001). The two polymorphic sites were in strong linkage disequilibrium, and maximum likelihood analysis supported the existence of three of the four possible haplotypes: S1-M1, S1-M2, and S2-M2. Since all S2 alleles were estimated to be present on M2-bearing chromosomes, the HTG-associated S2-M2 haplotype conferred the same approximate relative risk as the S2 allele alone when compared with the other two haplotypes (odds ratio 2.8). This study demonstrates that the S2 allele is a marker for HTG among west Japanese subjects as well as among Caucasians. The results suggest that S2-M2 chromosomes carry HTG susceptibility sequences that predate the separation of the Asian and Caucasian races.

[Osteoarthritis: clinical and epidemiological investigation]

A population study of 1,722 adults in Chenghai city, Guangdong province showed that the prevalence of osteoarthritis (OA) was 8.3% and there was no significant difference between male and female. The prevalence of OA increased after the age of 40 and reached a peak at 50-55 years. The prevalence of osteoporosis (OP) in OA patients of this population survey and in patients in our clinic was around 30%. OA accompanying OP was more frequently seen in female than male, especially in postmenopausal women. The results of CT screen of lumbar spine in 66 OA patients showed: 89.4% (59 cases) was associated with the protrusion of intervertebrale disc, occurring frequently at L4 and L5. MR imaging of 20 knee joints in 10 cases of OA patients with knee involvement showed: all of the patients were associated with one or all of the following conditions: chondropathies, degeneration or injury of semilunar plate, bursitis and synovitis. It is suggested that OA is a heterogeneous disorder and must be treated with different ways.

[Olfactory neuroblastoma: a histopathological ultrastructural and immunohistochemical study of 11 cases]

Eleven cases of olfactory neuroblastoma (ONB) were studied histopathologically, ultrastructurally and immunohistochemically. Light microscopical examination showed the tumor cell nests separated by fibrous connective tissue (present in 10/11 ONB), Homer-Wright rosette and/or Flexner rosette (9/11 ONB) and acidophilic fibrillary background (8/11 ONB). Ultrastructurally, there were neurosecretory granules (2/2 ONB) and neurofibrils (1/2 ONB) in cytoplasm of tumor cells. A panel of antibodies were used to characterize the immunohistochemical staining profile of ONB. The following results were obtained for the 11 neoplasms that were immunostained: NSE 11/11 (+), S-100 3/11 (+), Vimentin 4/11 (+), Keratin 1/11 (+) and NF, EMA, CEA, LCA all negative respectively. The significance of the morphological and immunohistochemical features of ONB in diagnosis and differential diagnosis were discussed.

[Rheumatic diseases in China]

To determine the prevalence of rheumatic diseases in Chinese of Han nationality in the north and the south of China, samples of 4,192 adults in Beijing (north) and 5,057 in Shantou (south) area were studied. The same questionnaire was administered to each subject surveyed. Physical examinations were done in all who gave positive answers. For those who gave positive response to certain set of questions, blood antinuclear antibody and rheumatoid factor tests and radiographs of hand and/or sacroiliac joint were done. The prevalence of definite rheumatoid arthritis (RA) was 0.34% in the north (95% confidence interval 0.20-0.51) and 0.32% (0.95% CI 0.16-0.47) in the south and ankylosing spondilitis was noted in 0.26% of both samples (95% confidence interval in the north 0.11-0.42 and in the south 0.14-0.40). Only 3 cases of systemic lupus erythematosus in the north and one in the south were identified. General rheumatic pain was reported more frequently in the north. Lumbar problems were recorded on examinations 5 times more commonly in the north than in the south (men 25.0% vs 5.3%, women 38.0% vs 6.5%) and knee problems 10 times (men 24.0% vs 1.8%, women 36.0% vs 3.4%) more commonly in the north; the difference was greatest in the age of 55-64. A further study in the south is planned to assess the contribution of inter-observer error and/or difference in cultural response to the north/south difference observed in the prevalence of general rheumatic symptoms and back pain. A search for environmental risk factors such as climate, diet, degeneration or overuse would then be indicated to explain these differences.

Expression of a rat vasopressin transgene in rat testes

The rat vasopressin gene contains two transcriptional promoters; the activity of one is confined to the hypothalamus, while the other is testis specific. To define the sequences mediating the cell-specific expression of the vasopressin gene, we introduced rat vasopressin transgenes into the rat germ line. Neither transgene 1.5-V beta gal-0.2, which consists of the entire vasopressin structural gene containing a 3 kbp beta-galactosidase reporter element in exon III, flanked by 1.5 kbp upstream of the start of hypothalamic transcription and 0.2 kbp downstream of the polyadenylation site, nor transgene 3-V beta gal-0.2, which consists of the entire VP structural gene containing a 3 kbp beta-galactosidase reporter element in exon III, flanked by 3 kbp upstream of the start of hypothalamic transcription and 0.2kbp downstream of the polyadenylation site, were expressed in the hypothalamus. This contrasts with a previously described transgene consisting of the rat vasopressin structural gene containing a reporter in exon III, flanked by 5 kbp of upstream and 3 kbp of downstream sequences, which is expressed in vasopressinergic hypothalamic neurons. Both the 3-V beta gal-0.2 and 1.5-V beta gal-0.2 transgenes were expressed in testicular germ cells using a promoter located within the beta-galactosidase reporter element. Transgene RNA was most abundant during the late stages of meiosis. Rats bearing vasopressin-beta-galactosidase transgenes provide new models for the study of the mechanisms whereby an epigenetic choice is made between the use of a germ cell or a somatic promoter, and the stage-specific transcriptional regulation of a germ cell promoter during spermatogenesis.

Target-promoted alkylation of DNA

Inducible and selective alkylation of DNA was accomplished under neutral conditions by use of a silyl-protected phenol that served as a precursor for a highly reactive quinone methide. As expected, addition of fluoride triggered reaction of a model compound, 3-(tert-butyldimethylsiloxy)-4-[(p-nitrophenoxy)methyl]benzamide, and its oligodeoxynucleotide conjugate. Surprisingly, the silyl phenol was also specifically yet more slowly activated by the environment of duplex DNA in the absence of fluoride. This alternative process was associated with the hybridization of probe and target strands, and single-stranded DNA was unable to induce a similar activation. Therefore, DNA appears to effect its own alkylation by promoting the formation of an electrophilic and nondiffusible intermediate.

Cell specific expression of a vasopressin transgene in rats

A transgene consisting of the rat vasopressin structural gene containing a reporter in exon III, flanked by 5 kb of upstream and 3 kb of downstream sequences, is expressed in vasopressinergic, but not oxytocinergic, magnocellular neurons of rats. Functionally appropriate physiological stimuli increase transgene expression in magnocellular neurons in an exaggerated fashion; the magnitude of the transgene response to osmotic challenge exceeds that of the endogenous gene by 10-15 fold. Magnocellular vasopressinergic neurons in the rat are now accessible to rational and precise genetic perturbation of function and regulation.

Effects of Panax notoginseng saponins on myocardial adenosinetriphosphatase

Effects of total Panax notoginseng saponins (PNS) and Panax notoginseng saponin monomers Rb1 and Rg1 (Rb1, Rg1) on total ATPase and Na(+)-K(+)-exchanging ATPase of guinea pig heart were studied. It was found that PNS inhibited the total myocardial ATPase, but had no significant effect on the myocardial Na(+)-K(+)-exchanging ATPase. The total ATPase was inhibited by Rg1, and more clearly by Rb1. The automaticity and contractility of isolated guinea pig atria were inhibited by Rb1. Rg1 decreased the spontaneous frequency of isolated guinea pig right atrium, but not markedly the contractility of the left atrium. These results demonstrate that Rb1 is the main ingredient in PNS.

Observation on the changes of plasma cardionatrion before and after microwave acupuncture in coronary heart disease

This paper reports the therapeutic effect of microwave acupuncture (MWA) and its influence on the plasma level of cardionatrion. Twenty-eight cases with coronary heart disease (CHD) were systemically observed and investigated. Atrial natriuretic polypeptides (ANP) were determined by radioimmunoassay. Plasma level of ANP was elevated, the rising rate being 100%. The therapeutic effect of MWA in the 28 cases with CHD was 85.7%, the ECG improving rate was 82.2%. Effect of MWA was briefly discussed. The authors consider that the therapeutic effect of MWA in the treatment of CHD could be ascertained, and the measurement of plasma ANP concentration is a useful method and an objective parameter for further research.

Small-for-size liver transplanted into larger recipient: a model of hepatic regeneration

Orthotopic liver transplantation was performed in 60 recipient rats weighing 200 to 250 gm. Sixty rats of the same strain were used as liver donors, 30 weighing 100 to 140 gm (small for size) and the other 30 weighing 200 to 250 gm (same size). After 1, 2, 3, 4, 7 and 14 days (n = 5 each) DNA synthesis, nuclear thymidine labeling and mitoses were increased in both the small-for-size and same-size groups, but significantly more in the former. These changes were maximal after 48 to 72 hr, similar to but later than the well-known regeneration response after partial hepatectomy, which peaks at 24 hr in rats. Indirect indexes of regeneration of the transplanted livers also were measured: plasma or serum ornithine decarboxylase; insulin and glucagon serum levels; estradiol and testosterone serum levels (and their nuclear and cytosolic receptors); and transforming growth factor-beta, c-Ha-ras and c-jun mRNA expressions. With the small-for-size transplantation, these followed the same delayed pattern as the direct regeneration parameters. The small livers gradually increased in size over the course of 1 to 2 wk and achieved a volume equal to that of the liver originally present in the recipient. In contrast, no significant liver weight gain occurred in the transplanted livers from same-size donors despite the evidence of regeneration by direct indexes, but not by most of the surrogate parameters, including ornithine decarboxylase.

Cloning, sequencing and expression in E. coli of interferon-omega 1 gene

Human interferon omega 1 (huIFN-omega 1) gene was isolated and cloned from chromosome DNA derived from a Chinese fetal liver via polymerase chain reaction (PCR). By determining its nucleotide sequence we proved that the 88th codon should be GGA, coding for Gly. After engineering the original IFN-omega 1 gene clone to a form that may be expressed as a nonfused protein, we also took the IFN-omega 1 gene under the control of the PRPL promoter with an expression vector pBV220 in E. coli. The antivirus activity of the recombinant IFN-omega 1 is about 6.5 x 10(7) units/L CULTURE (OD600 = 0.75). Since IFN-omega 1 not only has antivirus activity but also shows considerably high homology with animal trophoblast proteins which have been proved antiluteolysins as a maternal recognition signal for pregnancy, we believe that study on it will be practically and theoretically significant.

[Determination of plasma endothelin-1 in aged patients with chronic obstructive pulmonary disease in its clinical significance]

The levels of plasma endothelin-1 (ET-1) were determined by radioimmunoassay in 25 aged healty men and 88 aged patients with chronic obstructive pulmonary disease (COPD) at different stages. The results showed that plasma ET-1 levels of stable patients with COPD did not significantly change, but it were significantly higher during attacks than that in healthy subjects; The levels of plasma ET-1 in the patients with cor pulmonale were significantly higher than those in the healthy and COPD patients. Plasma ET-1 levels of patients with cor pulmonale at acute exacerbation stage were the highest in all groups. It was demonstrated that ET-1 correlated negatively to PaO2 and PH and correlated positively to PaCO2 and blood creatinine. This study suggested that the elevation of ET-1 level may contribute to the pathophysiological changes in patients with COPD and cor pulmonale.

Rapid and simultaneous determination of monoamine oxidase A and monoamine oxidase B activities in mouse brain homogenates by liquid chromatography with electrochemical detection

Sensitive and rapid enzymatic assays have been developed and optimized to measure the separate and combined activities of monoamine oxidase A (MAO-A) and monoamine oxidase B (MAO-B) in mouse brain tissue homogenates using liquid chromatography with electrochemical detection (LCEC). The selectivity for the two isozymes is primarily afforded by use of selective substrates, 5-hydroxytryptamine (5-HT) for MAO-A and 3-methoxy-4-hydroxybenzylamine (MHBA) for MAO-B. The selectivity of the separate assays is further enhanced by the use of inhibitors, deprenyl to block MAO-B and clorgyline to block MAO-A. The dual assay procedure, which employs no inhibitors, shows remarkably enhanced selectivity for each of the isozymes through the use of the two substrates; the preferred substrate for one isozyme acts as an effective competitive inhibitor of the nontargeted substrate for that isozyme, leading to substantially decreased activity for the latter substrate. Using the dual assay, kinetic constants determined for MAO-A (mean +/- SD) were: Km,5-HT = 39 +/- 7 microM, Vmax,5-HT = 37.6 +/- 2.1 pmol/mg wet tissue/min, Km,MHBA = 341 +/- 75 microM, and Vmax,MHBA = 27.7 +/- 2.3 pmol/mg wet tissue/min; those for MAO-B were: Km,MHBA = 108 +/- 11 microM, Vmax,MHBA = 44.3 +/- 1.2 pmol/mg wet tissue/min, Km,5-HT = 1704 +/- 122 microM, and Vmax,5-HT = 12.0 +/- 0.3 pmol/mg wet tissue/min. The separate isozyme procedures, when used without selective inhibitors, reflect only 88.3% of the MAO-A activity using the 5-HT velocity and only 66.0% of the MAO-B activity using the MHBA velocity. On the other hand, when the dual assay is employed, 98% of the observed 5-HT velocity can be directly attributed to MAO-A, and 94% of the observed MHBA velocity can be directly attributed to MAO-B. The dual assay was employed to demonstrate the relative change in the activity of these two enzymes in whole mouse brain between 27 and 74 days of age. During this time, the MAO-B activity increased from approximately 40 to approximately 60% of the total MAO activity. Under typical conditions, results can be easily obtained from any of the three procedures outlined for 100 samples in less than 2 working days, including only 3.5 h for the LCEC portion.

[Effects of Panax notoginseng saponins on monophasic action potentials of heart and automaticity and contractility of isolated atria]

The effects of Panax notoginseng saponins (PNS) on monophasic action potentials (MAP) recorded from the myocardial surface by means of contact electrode were studied in 30 open-chest rabbits. The MAPA was increased and MAPD50, MAPD90 were prolonged with PNS (100, 200 mg.kg-1, iv), while the Vmax remained unchanged. PNS (300-1200 micrograms.ml-1) inhibited the automaticity of isolated guinea pig right atria and the contractility of the left atria. The positive inotropic action of ouabain (0.2 mumol.L-1) on isolated guinea pig left atria was decreased in the presence of PNS 300 micrograms.ml-1.

[Volatile oil in Ephedra sinica Stapf. and its processed products by GC-MS]

This paper deals with the changes in contents and chemical composition in the volatile oil of Ephedra sinica before and after processing. The results indicate that after processing, the more the substances of low boiling point, the higher their contents and vice versa. The changes are particularly obvious in yellow-fried Ephedra sinica.

Neuropeptide gene expression in transgenic animals

Transgenic animal techniques offer today's neuroscientist the ability to experimentally manipulate neurosecretory systems with a precision undreamt of by our predecessors. The range of techniques now available, building as it does on our growing knowledge of physiological systems at the inter- and intercellular level, allows us to critically define molecular lesions and ask about their consequences to the whole organism. Neuroscientist should grasp the opportunities afforded by these recent developments.

[Clinical observation of macular disease in patients with diabetic retinopathy]

The population was 65 cases (122 eyes) of diabetic macular disease. Background diabetic retinopathy was observed in 40 eyes, i.e., 32.80%. For the 82 eyes present proliferative diabetic retinopathy, i.e., 67.20%. According to Sigelmen's classification, 17 eyes were in stage I, i.e., 13.93% of the cases; 41 eyes were in stage II, i.e., 33.60% of the cases; 40 eyes were in stage III, i.e., 32.80% of the cases; 24 eyes were in stage IV, i.e., 19.67% of the cases. There were 122 eyes in this group. The visual acuity of 66 eyes showed > or = 0.3, i.e., 54.00%, while that of 56 eyes showed 40.3 i.e. 46.00%. Nearly half patients showed low visual acuity and loss of vision. This result was responsible for the cases who were at the late stage of diabetic and with a long history of diabetic or the diabetic was poorly controlled. So the writer appeal to ophthalmologists and physicians to prescribe the effective guides to all the diabetic patients. We suggest that it is important that dynamic observation be carried out of hemorhelological manifestation and early treatment diabetic retinopathy for the clinical prevention and treatment of diabetic retinopathy.

Augmentation of rat liver regeneration by FK 506 compared with cyclosporin

The immunosuppressive drug, FK 506, increased the regeneration response that follows 40% and 70% hepatectomy in rats. The effect was similar to that obtained with cyclosporin.

The effect of different types of hepatic injury on the estrogen and androgen receptor activity of liver

Mammalian liver contains receptors for both estrogens and androgens. Hepatic regeneration after partial hepatectomy in male rats is associated with a loss of certain male-specific hepatic characteristics. In this study we investigated the effects of lesser forms of hepatic injury on the levels of estrogen and androgen receptor activity in the liver. Adult male rats were subjected to portacaval shunt, partial portal vein ligation, hepatic artery ligation, or two-thirds partial hepatectomy. Another group of animals was treated with cyclosporine. At the time of sacrifice the livers were removed and used to determine the estrogen and androgen receptor activity in the hepatic cytosol. A significant reduction (p less than 0.05) in the hepatic cytosolic androgen receptor activity and a slight increase in the estrogen receptor activity occurred following total portosystemic shunting. Partial ligation of the portal vein, which produces a lesser degree of portosystemic shunting, had no effect on the levels of the estrogen and androgen receptor activity present within hepatic cytosol. Cyclosporine-treated animals had significantly greater (p less than 0.01) levels of estrogen receptor activity in the hepatic cytosol compared to vehicle-treated control animals. Levels of estrogen and androgen receptor activity within the hepatic cytosol remained unchanged after ligation of the hepatic artery. The reduction in the cytosolic estrogen and androgen receptor activity in the liver after partial hepatectomy was confirmed. In summary, certain types of hepatic injury are associated with profound changes in the estrogen and androgen receptor content within the liver.

Studies on the regulation of renin genes using transgenic mice

Transgenic mice are being used as an assay to identify the DNA sequences that direct the tissue specificity and physiological regulation of murine renin gene expression. In initial studies, a DNA segment encoding the duplicated renin gene, Ren-2, has been injected into the pronuclei of fertilized eggs homozygous for the Ren-1c allele. The 24 kb XhoI fragment utilized consists of 5.3 kb of upstream flanking sequences and 9.5 kb of 3' flanking sequence in addition to the 10 kb segment encoding the 9 exons of the natural gene. Seventeen transgenic founder mice were identified of which at least 7 exhibited evidence of transgene expression. The 4 expressing lines that have been studied in detail integrated from 5 to 15 copies of the transgene but expression was not proportional to the number of copies integrated. Qualitatively, expression is detected in the correct spectrum of tissues, and submandibular gland expression of the transgene responds appropriately to known hormonal modulators. However, quantitatively, the levels of expression deviate considerably from normal.

Effect of partial portal vein ligation on hepatic regeneration

To evaluate the effect of portal hypertension and diminished portal venous blood flow to the liver on hepatic regeneration, male rats were subjected to partial portal vein ligation and subsequently to a two-thirds partial hepatectomy. The levels of ornithine decarboxylase activity at 6 h after partial hepatectomy were greater (p less than 0.001) in the rats with prior partial portal vein ligation than in those without portal hypertension. The rats with prior partial portal vein ligation also had greater (p less than 0.005) levels of thymidine kinase activity at 48 h after partial hepatectomy than did those without portal hypertension. Hepatic sex hormone receptor activity was not affected by prior partial portal vein ligation either before or after partial hepatectomy. The reductions in both estrogen and androgen receptor activity observed in the hepatic cytosol after partial hepatectomy were similar to those observed in control animals. These data indicate that animals with portal hypertension having a diminished hepatic portal blood flow have a normal capacity to regenerate hepatic mass following a hepatic resection.

Mapping of the mouse atrial natriuretic factor gene. Evidence for tight linkage to the Fv-1 locus

The importance of atrial natriuretic factor (ANF) in the regulation of salt balance and blood pressure is now widely recognized, and it would be extremely informative for both physiologists and molecular biologists to have mutants available that exhibit abnormal expression of this peptide hormone. The most direct mutation would affect the structural gene itself by altering either its coding potential or its regulation. With this aim in mind, it is of considerable interest to accurately determine the chromosomal position of the ANF gene (Anf) in the mouse. This information would permit a comparison with known mutations and provide a means of screening for mutations at this locus. Using recombinant inbred mouse strains, we undertook the mapping of the mouse Anf gene and demonstrated linkage of the gene to the Friend virus susceptibility-1 (Fv-1) locus on chromosome 4. The mapping was performed using a restriction fragment length polymorphism extant between the two parental strains. No recombination event between Anf and the Fv-1 locus was evident in any of the 34 strains tested. The assignment of Anf to this region of chromosome 4 coincides with the reported position of the cribriform degeneration mutation, which includes in its phenotype an abnormal electrolyte distribution. We have, therefore, begun studying this mutation to determine whether a defect in ANF expression is the underlying cause of the phenotype. Thus far, we have found no major DNA rearrangement close to the Anf gene.