[Transsphenoidal microsurgery for pituitary adenoma: analysis of 3 fatal cases]

To prevent severe postoperative complications and increase the survival rate of patients with pituitary adenoma after transsphenoidal microsurgery, 3 fatal cases were analysed in terms of clinical features and caused of death. They included (1) the too deeply inserted suction apparatus with resultant midbrain damage; (2) bleeding from residual tumor into aphragma sellae and dura mater, entering the subarachnoid, causing spasm of the brain vessels. In order to avoid complication, it is necessary to follow strictly the rules for transsphenoidal microsurgery and improve surgical skills.

[Respiratory muscle function and serum enzymology in hyperthyroidism before and after treatment]

To investigate the effect of hyperthyroidism on respiratory muscle function and its possible mechanism, the thyroid function, serum enzymology, serum potassium, pulmonary function and respiratory muscle function were examined in 60 patients with Grave's disease before treatment and 26 patients among them after treatment, and 20 normal subjects as control. T3, T4, and FT4 increased while FVC and PImax, which reflect the respiratory muscle strength, and Pi/PImax, which reflects the reserve capacity of inspiratory muscle, decreased significantly in the 60 patients with Grave's disease, compared with the ones of normal subjects. The comparison of above measurements in the 26 patients between before- and after-treatment showed that respiratory muscle strength increased obviously along with the improvement of throid function. The serum enzymology, potassium and TSH, however, were not abnormal and not changed after treatment. The thyroid functions in 10 patients with hyperthyroid heart disease were not different, compared with the ones of other 50 patients without hyperthyroid heart disease, but their respiratory muscle strength was significantly lower than the ones of latter. The above results suggested that hyperthyroidism could lead to significant decrease of respiratory muscle strength and its reserve capacity, whereas treatment for hyperthyroidism would improve respiratory muscle function, so the measurement of respiratory muscle function in hyperthyroidism cases might be useful in prediction of hyperthyroid heart disease.

[Study on the NIR-Raman spectra and NIR-SERS spectra of amsacrine]

The near infrared surface-enhanced Raman spectra (NIR-SERS) of amsacrine,an anticancer agent, on silver collids were recored with high quality. The NIR-SERS enhancement factor is up to 10(4) magnitude. In comparison with the near infrared Raman (NIR-Raman) spectra of solid amsacrine, more information of vibrational structures of amsacrine molecules at low concentration and almost in its practical application envi ronment, can be given by the NIR-SERS. The enhancement mechanism is associated with the adsorption of acridyl ring and sulfonyl on silver surface.

BRCA1 physically associates with p53 and stimulates its transcriptional activity

Mutations of the BRCA1 tumor suppressor gene are the most commonly detected alterations in familial breast and ovarian cancer. Although BRCA1 is required for normal mouse development, the molecular basis for its tumor suppressive function remains poorly understood. We show here that BRCA1 increases p53-dependent transcription from the p21WAF1/CIP1 and bax promoters. We also show that BRCA1 and p53 proteins interact both in vitro and in vivo. The interacting regions map, in vitro, to aa 224-500 of BRCA1 and the C-terminal domain of p53. Tumor-derived transactivation-deficient BRCA1 mutants are defective in co-activation of p53-dependent transcription and a truncation mutant of BRCA1 that retains the p53-interacting region acts as a dominant inhibitor of p53-dependent transcription. BRCA1 and p53 cooperatively induce apoptosis of cancer cells. The results indicate that BRCA1 and p53 may coordinately regulate gene expression in their role as tumor suppressors.

[Oral low-dose magnesium gluconate preventing pregnancy induced hypertension]

OBJECTIVE

To study the effects of oral low-dose magnesium gluconate in prevention of pregnancy induced hypertension (PIH) and its mechanism.

METHODS

A prospective randomized double-blind study was carried out in 51 pregnant women as treatment group (including 22 cases as treatment group 1 and 29 cases as treatment group 2) and 51 pregnant women as controls (including 28 cases as controls group 1 and 23 cases as control group 2). Low-dose magnesium gluconate (3 g/day) or placebo was given from the 28th week of gestation to delivery consecutively.

RESULTS

4% of the pregnant women developed PIH after magnesium gluconate treatment, which was substantially lower than that in the control group (16%) (P < 0.05). In the treatment group 2, women showed higher concentration of 6-keto-prostaglandin F1 alpha (PGF1a) and 6-keto-/thromboxane B2(TXB2) (P/T) ratio than that of the control group 2. Moreover, TXB2 level was lower than that in the control group 2. In the treatment group 1 women showed higher ratio of P/T than that of the control group 1. There were no significant differences of serum magnesium concentration among all groups.

CONCLUSION

Low-dose magnesium gluconate may efficiently prevent PIH in high risk women. The mechanism of action of magnesium gluconate probably involves to keep the balance of PGI2 and TXA2, but not associates with serum magnesium level.

Molecular Transport and SAPO-11 Crystal Growth in an i-Pr2NH-AlPO4-H3PO4-SiO2-H2O System

The crystal growth of SAPO-11 molecular sieve synthesized with i-Pr2NH as a novel template from mixtures of Si, Al, and P sources were studied by XRD, MAS-NMR, IR, and AAS techniques. It was found that the crystallization was improved partially by the desorption of i-Pr2NH from the crystallite products at high temperatures. The growth on (010) face was enhanced by stepwise adding external silica sol to the reaction mixtures during the synthesis process. The molecular transport and mechanism of the crystallization were discussed. Copyright 1997 Academic Press. Copyright 1997Academic Press

The involvement of serine 175 and alanine 185 of cytochrome b of Rhodobacter sphaeroides cytochrome bc1 complex in interaction with iron-sulfur protein

An approach involving cysteine replacement of potentially noncritical amino acid residues, followed by chemical modification studies, was used to investigate structure-function of the "cd helix" of cytochrome b from Rhodobacter sphaeroides. Three amino acid residues, Ser-155, Ser-175, and Ala-185, which span this region of cytochrome b, were selected for this study. The S155C substitution yields cells unable to support photosynthetic growth, indicating that Ser-155 is a critical amino acid residue. Further mutational studies of Ser-155 indicate that the size of the amino acid side chain at this position is critical for photosynthetic growth of R. sphaeroides. On the other hand, the S175C and A185C substitutions yield cells with photosynthetic growth rates and enzyme kinetics of the bc1 complexes very similar to those of the unmutated complex, indicating that Ser-175 and Ala-185 are noncritical residues. Thus, engineered cysteines at these two positions of cytochrome b are suitable for membrane topology and domain/subunit interaction studies. Cys-175 does not react with a sulfhydryl-modifying reagent, N-ethylmaleimide (NEM), either in sealed, inside-out chromatophores or in detergent-disrupted chromatophores, indicating that position 175 of cytochrome b is inaccessible from both sides of the membrane and is probably buried within the protein complex. Cys-185 reacts with NEM only after detergent disruption of the sealed, inside-out chromatophores, indicating that this position of cytochrome b is accessible on the outer (periplasmic) surface of the membrane. These results place the cd helix of cytochrome b on the periplasmic side of the chromatophore membrane. When purified A185C-substituted bc1 complex was treated with NEM, about 87% of the activity was abolished due to NEM modification of Cys-185. The signature of the Rieske iron-sulfur center is broadened upon NEM modification of A185C, with the gx signal shifting from g = 1.80 to g = 1.75, suggesting that Ala-185 of cytochrome b interacts with the iron-sulfur protein. When purified S175C-substituted bc1 complex is treated with NEM, no change in the activity is observed, since Cys-175 is inaccessible to NEM. However, when the iron-sulfur protein is removed from the S175C-substituted bc1 complex, Cys-175 becomes accessible to NEM, indicating that Ser-175 of cytochrome b is shielded by the iron-sulfur protein in the bc1 complex.

Modulation of multidrug resistance by three bisbenzyl-isoquinolines in comparison with verapamil

AIM

To compare cycleanine (Cyc), insularine (Insr), insulanoline (Insn) and verapamil (Ver) in modulation of multidrug resistance (MDR) in vitro.

METHODS

The cytotoxic effect was determined by 3-[4, 5-dimethylthiazol-2-yl], 5-diphenyl tetarzolium bromide (MTT) assay. The intracellular doxorubincin (Dox) accumulation was assayed by spectrofluorometer.

RESULTS

Cyc, Insr, Insn, and Ver showed significant activities in modulating Dox and vincristine resistances in acquired resistant MCF-7/Adr and KBv200 cell lines in a dose-dependent manner. Cyc, Insr, Insn, and Ver increased intracellular Dox accumulation in MCF-7/Adr cells. Cyc and Insr had greater activities than Ver in modulating MDR, while Insn had similar activity to that of Ver.

CONCLUSION

MDR was modulated by Cyc, Insr, and Insn, due to the increase of intracellular Dox accumulation.

[Water vapor permeability measurement of the materials used as a wound covering]

This paper introduces a new apparatus and method that suits to measuring the water vapor transmission rate (WVTR) of wound covering materials. WVTR of synthetic materials, amniotic membrane, porcine and cadaveric skin was measured under different conditions of four temperatures, three mediums, and "water cup" or "inverted water cup". The temperature was in close relationship with the WVTR except Omiderm, amniotic membrane, and cadaveric skin between 30 degrees C and 37 degrees C groups. The medium did not affect the WVTR (P > 0.05). There was significant difference between the "water cup" and "inverted water cup" groups(P < 0.01). This study suggests that the apparatus is easy-to-operate, reliable and suitable for the measurement of WVTR of burn wound coverings and other membranous materials.

[Comparison of the Chinese LJ strain structural gene with HM175, MBB, LA strains and the expression of hepatitis A virus antigen by LJ/HM175 recombinant vaccinia virus]

The nucleotide and amino acid sequences of a Chinese hepatitis A virus Long-Jia (LJ) strain were compared with that of HM175, MBB and LA strains in structural genes (nt 630-3049). The most extensive nucleotide homology was identified between LJ and MBB strains. The identity rates of nucleotide were 95.4%, 96.7% and 91.4%, respectively. Variation rates of amino acid were 0.91%, 0.91% and 2.98%, respectively. A total of 23 amino acid differences located in whole capsid region between LJ and LA strain, especially in VP1. Only 7 amino acid differences located in VP2 and VP3 between LJ and HM175/MBB strain. Restriction enzyme sites increased 10, 13 and 30 sites in 56 restriction enzymes tested, and decreases 15, 1 and 27 sites, respectively. BstE II (nt 2810) and Pvu I (nt 2013) were the peculiar sites of LJ strain. Hind III, Pst I and Sac I sites were identical among the four strains. After structural gene (nt 745-2993) of HM175 strain was replaced by LJ strain, the complete hepatitis A virus cDNA open reading frame was inserted into pJSA1175 (vaccinia virus expression vector) downstream of promoter 7.5 k. Hepatitis A virus antigen expressed was 1:16 in titer by sandwich ELISA. Band-patterns of anti-VP0, anti-VP1 and anti-VP1, 2, 3, were as same as that of HM175 strain and natural hepatitis A virus antigen by Western blot analysis.

Expression and regulation of steroid 5 alpha-reductase in the genital tubercle of the fetal rat

The genital tubercle is a bipotential anlage that can develop into a penis or a clitoris. Formation of the penis requires synthesis within the tubercle of the androgen dihydrotestosterone by steroid 5 alpha-reductase isozymes. Isozyme 1 mRNA and protein were present in epithelial cells, whereas isozyme 2 transcripts were present in mesenchymal cells of developing genital tubercles from day 17, 19, and 21 rat embryos. These expression patterns were observed in both uncommitted anlagen and in committed male or female structures. Androgens did not significantly influence levels of 5 alpha-reductase mRNAs or affect their cellular distributions. Together with genetic data, the results implicate the mesenchyme as the crucial cell type in formation of the male external genitalia.

[A comparative study on effect of two bisbenzylisoquinolines, tetrandrine and berbamine, on reversal of multidrug resistance]

A comparative study on the effect of two bisbenzylisoquinolines, tetrandrine (TTD) and berbamine (BBM), and verapamil (VRP) on reversing multidrug resistance was reported. TTD, BBM and VRP showed significant activity in reversing adriamycin (ADR) and vincristine (VCR) resistance in acquired resistant MCF-7/Adr and KBv200 cell lines, and the effect was shown to be dose-dependent. TTD, at the concentration of 10 mumol.L-1, completely reversed ADR resistance in MCF-7/adr cells. TTD, BBM and VRP increased intracellular ADR accumulation in MCF-7/adr cells. There is minor difference in structure between TTD and BBM. TTD showed greater activity than VRP in reversing MDR, while BBM showed similar activity to that of VRP. TTD also showed significant activity in vivo in reversing ADR resistance in MDR MCF-7/Adr solid tumor in nude mice.

Molecular characterization of two mammalian bHLH-PAS domain proteins selectively expressed in the central nervous system

Here we describe two mammalian transcription factors selectively expressed in the central nervous system. Both proteins, neuronal PAS domain protein (NPAS) 1 and NPAS2, are members of the basic helix-loop-helix-PAS family of transcription factors. cDNAs encoding mouse and human forms of NPAS1 and NPAS2 have been isolated and sequenced. RNA blotting assays demonstrated the selective presence of NPAS1 and NPAS2 mRNAs in brain and spinal cord tissues of adult mice. NPAS1 mRNA was first detected at embryonic day 15 of mouse development, shortly after early organogenesis of the brain. NPAS2 mRNA was first detected during early postnatal development of the mouse brain. In situ hybridization assays using brain tissue of postnatal mice revealed an exclusively neuronal pattern of expression for NPAS1 and NPAS2 mRNAs. The human NPAS1 gene was mapped to chromosome 19q13.2-q13.3, and the mouse Npas1 gene to chromosome 7 at 2 centimorgans. Similarly, the human NPAS2 gene was assigned to chromosome 2p11.2-2q13, and the mouse Npas2 gene to chromosome 1 at 21-22 centimorgans. The chromosomal regions to which human NPAS1 and NPAS2 map are syntenic with those containing the mouse Npas1 and Npas2 genes, indicating that the mouse and human genes are true homologs.

Endothelial PAS domain protein 1 (EPAS1), a transcription factor selectively expressed in endothelial cells

Here we describe the cloning and characterization of a PAS domain transcription factor termed endothelial PAS-1 (EPAS1). This protein shares 48% sequence identity with hypoxia inducible factor (HIF-1alpha) and lesser similarity with other members of the basic helix-loop-helix/PAS domain family of transcription factors. Like HIF-1alpha, EPAS1 binds to and activates transcription from a DNA element originally isolated from the erythropoietin gene and containing the sequence 5'-GCCCTACGTGCTGTCTCA-3'. Activation by both HIF-1alpha and EPAS1 is stimulated by hypoxic conditions. EPAS1 forms a heterodimeric complex with the aryl hydrocarbon nuclear transporter prior to transcriptional activation of target genes. EPAS1 expression is limited to the endothelium of mouse embryos and, in agreement with its cell type-specific expression pattern, is capable of specifically activating the transcription of the endothelial tyrosine kinase gene Tie-2. These observations raise the possibility that EPAS1 may represent an important regulator of vascularization, perhaps involving the regulation of endothelial cell gene expression in response to hypoxia.

A simple and quick method to evaluate the influence of food price policy on population-based nutrition status and related nutrition intervention

Food price policies have a major influence on population food choice and nutritional status, especially for low-income families. Therefore, simple and quick methods to evaluate their influence is desirable. Consistent with nutritional rationality and economical feasibility, a mathematical model was developed by Linear Programming to appraise the influence and rationality of the subsidization of egg and pork in Tianjin, using the data about food varieties and their prices in Tianjin in 1990. It was found that food subsidism to influence choice was not rational for improvement in nutritional status of low-income families. The concept, of "food choice space" was developed and its implications for nutrition intervention explored. The model developed can be used to judge the nutritional effect of food price policies and provide baseline data for nutrition intervention.

Gamma radiation effect on vascular smooth muscle cells in culture

PURPOSE

Prior work in our laboratory demonstrated that external gamma irradiation administered within 48 h following balloon catheter carotid artery injury in rats produced a marked inhibition of intimal hyperplasia and restenosis. The current study used smooth muscle cells (SMC) in vitro to examine the radiation dose response and to investigate the cellular mechanism by which radiation inhibits SMC proliferation.

METHODS AND MATERIALS

Quiescent rat aortic SMC in plasma were refed with whole blood serum to stimulate synchronous proliferation and immediately irradiated with single fraction doses of 1.25-20 Gy.

RESULTS

Comparison between a micronucleus assay and a clonogenic assay indicated a dose-dependent inhibition of SMC growth, with an ED50 at 2-3 Gy. The micronucleus assay also demonstrated a dose-dependent increase in apparent chromosomal damage at 72 h after irradiation. Inhibition of SMC growth by radiation did not correlate with changes in intracellular or released mitogenic activity. Furthermore, there was no evidence of apoptosis in irradiated SMC up to 96 h after treatment.

CONCLUSION

Radiation likely inhibits SMC proliferation after arterial injury by a dose-dependent mechanism of lethal and/or sublethal cellular injury leading to clonogenic cell death.

[A study of insulin sensitivity and its related factors in patients with non-insulin dependent diabetes mellitus and impaired glucose tolerance]

In order to evaluate insulin sensitivity and its related factors in abnormal glucose tolerance, 572 cases of non-insulin dependent diabetes mellitus (NIDDM), 647 cases of impaired glucose tolerance (IGT) and 543 normal controls were studied. The results showed that fasting insulin levels (FIns) and the prevalence of hyperinsulinemia were higher in NIDDM than that in IGT and higher in IGT than that in normal controls (P < 0.01). Insulin sensitivity index (ISI) [-ln(FInx x fasting blood glucose)] ranked from high to low in the order of normal controls, IGT subjects, newly-diagnosed NIDDM patients and patients with known NIDDM (P < 0.01). In each group ISI was smaller in obese subjects or patients than in non-obese ones. Mono-factor analysis demonstrated that ISI in each group was negatively related to body mass index (BMI) and positively related to high density lipoprotein (HDL)-cholesterol. ISI in NIDDM and IGT group was negatively related to blood pressure. Multiple analysis showed that the ISI had significantly negative correlation with BMI and some correlation with blood pressure and blood lipids. In conclusion, the patients with abnormal glucose tolerance had hyperinsulinemia and insulin resistance. ISI was related to some risk factors of vascular diseases.

[The effects of intensive DMPA regimen in the treatment of Graves' ophthalmopathy]

35 patients with Graves' ophthalmopathy were treated with DMPA regimen which included dexamethasone (D) 20-30 mg and Methotrexate (M) 15-20 mg i.v. once a week and prednisone (P) 20 mg/d p. o. 4 times a week for 4 weeks followed by addition of azathioprine (A) or 6-MP 75-100 mg/d and the increment of prednisone (20 mg/d) to 5 times a week in the fifth and sixth weeks. The full intensive course of therapy lasted for 6 weeks. If necessary, the similar course of therapy might be repeated. Later on, each patient was mintainted on a therapy with P and A or P and 6-MP for another 1-2 months then the P and A or P and 6-MP for another 1-2 months, and then the P and A or 6-MP were tapered and finally discontinued at the end of sixth month. The symptoms and signs of the opthalmopathy were evaluated blindedly at the beginning and the end of the first and second courses of the therapy by two ophthalmologists. The results showed that the symptoms and signs were significantly improved in 33 (94.3%) cases. A decrease of eyeball protrusion of 1.22 +/- 1.15 and 1.28 +/- 1.15 mm in the left and right eyes respectively was shown by eophthalmometry reading (both P < 0.0005, compared with before and after the therapy). The decrease of exophthalmos was more remarkable in the cases with ophthalmopathy for < or = 1 year than that > 1 year. 11/22 patients recovered their ability to close eyes adequately. The diplopia was corrected in 8/15 cases. The mobility of eye ball returned to normal in 5/15 cases. Exposed lesion and/or ulceration of the cornea found in 7 patients were cured. Serious side and/or toxic effects of the drugs were not present during the course of therapy. It is suggested that DMPA regimen is an effective, safe and cheap approach to the treatment of Graves' ophthalmopathy.

Study of the prevalence of diabetes mellitus in adults in the Shougang Corporation in Beijing

The aim was to determine the burden of diabetes mellitus (DM) in an urban area of China to aid us in planning preventive measures for those at risk of DM. A survey was conducted among the 29,859 subjects aged between 30 and 64 belonging to 32 units of the Shougang Corporation (a heavy industry enterprise) within the Beijing area. WHO study protocols and diagnostic criteria were used to determine the prevalence of DM and impaired glucose tolerance (IGT). The results showed that the age-adjusted prevalence of DM and impaired glucose tolerance (IGT) was 3.63% and 4.19%, respectively, both increasing with age. Peak prevalence for both occurred in the 60-64 age group. Prevalence showed no difference between the sexes in DM but was higher for females in IGT. Obesity, being overweight, a family history of diabetes mellitus and in women, a history of delivering babies with macrosomia, all correlated closely with the prevalence of DM and IGT. High protein intake was also associated with DM, Smoking had no effect on either DM or IGT. Intellectual workers had a higher incidence of IGT than manual workers. Seventy per cent DM was undiagnosed prior to the survey. This survey, done according to the recommendation of WHO, and including appropriate adjustments, reflects the growing prevalence of DM and IGT in this population. It can be compared with other studies for epidemiological analysis.

[Prevalence and risk factors of hypertension and coronary heart disease in the subjects with abnormal glucose metabolism]

The prevalence and risk factors of hypertension and coronary heart disease (CHD) in subjects with abnormal glucose metabolism (AGM) were studied in a population of 29,960 in the Capital Iron and Steel Corporation. The results showed that the prevalences of hypertension and CHD were 37.37% and 9.32% in diabetes group and 29.88% and 6.25% in impaired glucose tolerance group respectively. Both aging and obesity were the risk factors for AGM, hypertension and CHD. Hyperglycemia and hyperlipidemia were related to the occurrence of hypertension and CHD. Our results indicate that the prevalence of CHD and hypertension is significantly increased in AGM subjects, and they have many other risk factors of cardiovascular disease.

Multiple organ injuries and failures caused by shock and reperfusion after gunshot wounds

Experiments were performed to observe the changes of multiple system organ failure (MSOF) and gut barrier function caused by shock and reperfusion after gunshot wounds. Eighteen dogs were divided randomly into two groups. In the experimental group, the dogs were subjected to 60 minutes of shock (40mm Hg), followed by reinfusion of shed blood after hindlimb gunshot wounds. In the control group, the dogs experienced pure gunshot wounds without shock and reperfusion. The results showed that dogs in the experimental group developed multiple system organ injuries or failures compared with the control group. The levels of malondialdehyde (MDA) values in plasma were significantly elevated in the experimental group when compared with preinjury and the control group. Gut flora disorder, bacillus intestinalis overgrowth, and bacterial translocation occurred in the experimental group. The pathological results support the gut barrier function injury. The results indicated that pure gunshot wounds do not easily injure gut barrier function and produce MSOF. Gunshot wounds with shock and reperfusion are capable of causing gut flora disorder, bacillus intestinalis overgrowth, and lead to bacterial translocation, furthermore causing MSOF. Although fluid resuscitation is a potential treatment modality, pathogenically, it can lead to MSOF.

In vivo effects of tumor necrosis factor-alpha on incised wound and gunshot wound healing

Recombinant tumor necrosis factor alpha (TNF-alpha) was applied to incised wounds (adult rats, n = 14) and gunshot wounds (dogs, n = 5). The accumulation of RNA and DNA in regenerative tissue, the wound disruption strength (WDS), and histology were examined. The results showed that a single dose of TNF-alpha in saline with highly purified bovine serum albumin increased the WDS and accumulation of RNA and DNA in regenerative tissue in incised wounds 3 days after surgery (p < 0.05). Also, TNF-alpha promoted the inflammatory reaction in the wounded area of gunshot wounds. Histology revealed increased capillary tube-like structures and collagen formation and fibroblast proliferation in both incised and gunshot wounds treated with TNF-alpha. The results indicated that locally applied TNF-alpha benefited the incised and gunshot wound healing. These mitogenic and inflammatory effects of TNF-alpha may be the synergistic effects with other growth factors such as platelet-derived growth factor (PDGF).

[An experimental study on injury of intestinal immuno-barrier in rat after scald]

A dynamic observation on injury of intestinal immuno-barrier in scalded rat was performed to investigate the relationship between the injury of intestinal immuno-barrier and bacterial translocation. After 40% TBSA third degree scald, a decrease of IgA in intestinal content and the number of CD3+ and CD4+ T lymphocyte, and reduction of IgA coat rate of intestinal bacteria were observed. At the same time, an increase in the incidence of bacterial translocation was detected. The results indicated that intestinal immuno-barrier was damaged and its protective function was weakened after an extensive thermal injury, and it suggested that the injury of intestinal immuno-barrier might play an important role on the development of postburn bacterial translocation and postburn sepsis.