Anatomical and physiological measures of auditory system in mice with peripheral myelin deficiency

Animal models with genetic abnormalities have been increasingly used in auditory research. Both TrJ mice and Po-DT-A mice are animals with peripheral myelin deficiency. In TrJ mice, the defect is due to a mutated PMP-22 gene. In Po-DT-A mice, the defect is produced by a transgene using the rat Po promotor to direct the expression of gene encoding for the bacterial diphtherial toxin A chain (DT-A). This study evaluates the auditory system both physiologically and histologically in these two strains of mice. Histological examination revealed that there was myelin deficiency of the auditory nerve fibers, accompanied by a loss of dendrites and a loss of spiral ganglion cell bodies in both strains of mice. In general, histological deficits in TrJ mice were greater than those in Po-DT-A mice. There was a strong correlation between the degree of myelin deficiency and the survival of spiral ganglion neurons. ABR measurements exhibited differences in threshold, latency and slope of the ABR growth function between myelin-deficient mice and their respective controls. These results suggest that the integrity of the myelin in the auditory nerve is important both for neural survival and for normal electrophysiological function of spiral ganglion neurons.

Physical and transcriptional map of an aflatoxin gene cluster in Aspergillus parasiticus and functional disruption of a gene involved early in the aflatoxin pathway

Two genes involved in aflatoxin B1 (AFB1) biosynthesis in Aspergillus parasiticus, nor-1 and ver-1, were localized to a 35-kb region on one A. parasiticus chromosome and to the genomic DNA fragment carried on a single cosmid, NorA. A physical and transcriptional map of the 35-kb genomic DNA insert in cosmid NorA was prepared to help determine whether other genes located in the nor-1-ver-1 region were involved in aflatoxin synthesis. Northern (RNA) analysis performed on RNA isolated from A. parasiticus SU1 grown in aflatoxin-inducing medium localized 14 RNA transcripts encoded by this region. Eight of these transcripts, previously unidentified, showed a pattern of accumulation similar to that of nor-1 and ver-1, suggesting possible involvement in AFB1 synthesis. To directly test this hypothesis, gene-1, encoding one of the eight transcripts, was disrupted in A. parasiticus CS10, which accumulates the aflatoxin precursor versicolorin A, by insertion of plasmid pAPNVES4. Thin-layer chromatography revealed that gene-1 disruptant clones no longer accumulated versicolorin A. Southern hybridization analysis of these clones indicated that gene-1 had been disrupted by insertion of the disruption vector. These data confirmed that gene-1 is directly involved in AFB1 synthesis. The predicted amino acid sequence of two regions of gene-1 showed a high degree of identity and similarity with the beta-ketoacyl-synthase and acyltransferase functional domains of polyketide synthases, consistent with a proposed role for gene-1 in polyketide backbone synthesis.

ImmunoMax. A maximized immunohistochemical method for the retrieval and enhancement of hidden antigens

BACKGROUND

Since the introduction of mAb, immunohistochemistry has become an important tool in research and in surgical pathology. The most widely used fixative in routine histopathology is formaldehyde, and it has become the gold standard for morphologic tissue preservation. Although the molecular mechanism underlying the tissue fixation is not well understood, it has become clear that available immunoreactive Ag are progressively lost during the fixation process. For a long time, it was thought that formalin-sensitive Ag might be irreversibly destroyed during the fixation process. Although monoclonal anti-Ig Ab frequently worked inadequately, polyclonal anti-Ig Ab were shown to produce reproducible staining results. It thus appeared possible that most cellular Ag might not be irreversibly destroyed but only masked.

EXPERIMENTAL DESIGN

Although some Ag may be retrieved under appropriate conditions, there might still be many for which available antigenic epitopes are still too sparse to be visualized, as observed for a large number of leukocyte differentiation Ag. One reliable approach to resolve this dilemma is the use of a combination of an optimized Ag retrieval system and a powerful immunohistochemical staining protocol introducing a biotin amplification step, in which signal amplification is accomplished by covalent deposition of biotin molecules.

RESULTS

Cryostat and paraffin sections were stained with the avidin-biotin complex technique and, for comparison, with the new maximized immunohistochemical staining protocol, termed the ImmunoMax method. Each step was monitored to establish how effectively it enhanced the overall sensitivity. Although pretreatment with detergent, protease, a chaotropic substance, or microwave heating resulted in only moderately improved immunostaining, the biotinylated tyramine enhancement step proved to be the most efficient one, although the latter is not sufficient for many Ag when used without pretreatment steps. The combination of an Ag retrieval step with the biotinylated tyramine enhancement step resulted in a 100 to 10,000-fold boost in sensitivity without loss of specificity.

CONCLUSIONS

With the ImmunoMax method, defined Ag can be reproducibly detected in formalin-fixed, paraffin-embedded tissues, and the sensitivity of the method is tremendously enhanced. Moreover, it also allows many previously unreactive or unsatisfactorily reactive Ag to be detected, as shown here for IgD, IgM, and CD7 with the use of mAb.

Immunogold labeling of oncogenic and tumor related proteins

Immunogold labeling electron microscopy technique has been used to study the ultrastructural localization of oncogenic proteins: Mos, Met, Ski, and the tumor-associated protein, Muc1, as well as their relationship with other tumor-related proteins. By pre- and postembedding immunogold labeling electron microscopy techniques, we showed that the Mos protein pp39mos colocalized with microtubule bundles, suggesting that microtubulin or microtubule-associated protein(s) may be the substrate of Mos. Met protein was labeled at the microvilli of the lumen that are formed in cultured T47D cells, implying its potential involvement in lumen formation. Ski localization experiments revealed a unique globular structure "Ski body" that is present inside the nucleus of interphase chicken embryo fibroblast infected with Ski cDNA FB29 and FB2-29. Ski bodies were also found scattered in the cytoplasm of metaphase FB29 and FB2-29 Ski expressing chicken embryo fibroblasts. In T47D cells, tumor-associated protein Muc1 was associated with both the plasma membrane and the membranes of secretory vesicles in the cytoplasm. In MUC1 infected NIH3T3 cells, however, labeling showed that in addition to the plasma membrane and the membranes of secretory vesicles, some Muc1 gold spheres were seen inside the secretory vesicles, suggesting that the subcellular localization of the protein may vary in different cell types.

[Comparative study of umbilical artery Doppler velocimetry, antenatal fetal heart rate monitoring and umbilical artery blood-gas analysis in the prediction of neonatal outcome]

One hundred and fifteen term pregnancies (62 normal pregnancies, 53 high risk pregnancies) were observed by umbilical artery Doppler velocimetry (UmA S/D ratio) and antenatal fetal heart rate monitoring (NST), and 37 of them were also observed by umbilical artery blood-gas analysis at birth. We compared the effects of these three methods to predict the neonatal outcome. The standards of the neonatal poor outcome were 5-min Apgar score < or = 7 and/or a birth weight < 2500g (SGA). The results were: (1) The neonatal poor outcome were more frequently observed in the abnormal UmA S/D ratio (> or = 3.0) group and in the UmA pH < or = 7.2 group (P < 0.005, P < 0.025, respectively), but there was no significant difference between the NST reactive or nonreactive groups (P > 0.05); (2) The neonatal acidosis at birth was also associated with the abnormal UmA S/D ratio (> or = 3.0); (3) The sensitivities of UmA S/D ratio, UmA pH, NST to predict the 5-min Apgar score < or = 7 were 60.0%, 60.0%, 20.0% respectively; the specificities 84.6%, 81.3%, 81.8% respectively. And their sensitivies to predict SGA were 100.0%, 100.0%, 40.0% respectively; the specificities 86.4%, 80.0%, 82.7% respectively. Our data show that UmA S/D ratio and UmA pH are better than NST in the prediction of neonatal outcome, and the abnormal UmA S/D ratio is closely associated with neonatal acidosis at birth.

Isolation and expression analysis of tyro3, a murine growth factor receptor tyrosine kinase preferentially expressed in adult brain

Growth factors and their receptors function in the nervous system to induce proliferation and differentiation of neuronal precursor cells and to support survival of mature neurons. We have isolated a murine growth factor receptor tyrosine kinase using an anti-phosphotyrosine antibody screening procedure and studied the pattern of expression. The deduced amino acid sequence of the kinase has all the characteristics of a growth factor receptor and consists of a putative extracellular domain, a transmembrane domain, and a tyrosine kinase domain. Sequence comparison with known receptor tyrosine kinases indicated that the murine kinase is a mouse homolog of tyro3. tyro3 belongs to the Axl/Ufo growth factor receptor family. In the putative extracellular domain, there are two Ig-like domains and two fibronectin type III repeats which are conserved in other members of the Axl/Ufo family receptors. Northern blot hybridization analysis showed that tyro3 is expressed at high levels in the brain of adult mice, although considerable expression was also observed in the testis. In situ hybridization analysis revealed that high levels of tyro3 are expressed in the cerebral cortex, the lateral septum, the hippocampus, the olfactory bulb, and in the cerebellum. The highest levels of tyro3 expression in the brain are associated with neurons. The preferential expression of tyro3 in specific regions of the adult mouse brain suggests that tyro3 may function as a novel neurotrophic factor receptor.

[The analysis of the causes and changes in maternal mortality in 42 years]

The causes and change of maternal death in this hospital from 1949 to 1990 was analyzed. The average maternal mortality of 42 years was 150.22/10(5) livebirths. The 42 years was divided into four periods which were 1949-1960, 1960-1970, 1971-1980 and 1981-1990. The results showed that the maternal mortality rate lowered from 365.31/10(5) livebirths in first period to 43.67/10(5) livebirths in the 4th period. The difference was markedly significant P < 0.01. The direct obstetric causes of maternal deaths in these periods were 30.00%, 23.81%, 25.00% and 55.56% respectively and increased in the 4th period. Obstetric hemorrhage (55.71%) pregnancy induced hypertension (31.43%) and preperal infection (11.43%) were the three main causes of maternal deaths in direct obstetric causes. Cardiac diseases (40.00%) was the leading cause in indirect causes.

Further observations on the human maximum safe dietary selenium intake in a seleniferous area of China

This report is a summarization of preliminary results from a study of dietary Se intake in a seleniferous area in order to determine safe levels. All patients have symptoms of toxicity: broken hair strands or various levels of nail damage. Finger-nail signs were the first symptoms used for diagnosis of selenosis in this work. Based upon the lowest blood-Se level of five subjects with persistent overt finger-nail signs of selenosis, it was found in 1986 that the individual marginal toxic blood Se level (LOAEL) and the corresponding Se intake were 1054 micrograms/L and 910 micrograms/d, respectively. To re-examine the clinical signs and blood Se levels of the five individuals and to see how the two are correlated, a study was conducted in July 1992 at the same location in the seleniferous area. The results showed that along with the absence of clinical signs, the average blood Se level had decreased from 1346 to 968 micrograms/L. The corresponding safe Se intake per day would be 819 +/- 126 micrograms (15 micrograms/kg B.W. or approximately 800 micrograms per day, which is suggested as the mean No Adverse Effect Level (NOAEL), and the lower limit of the 95% confidence interval, 600 micrograms per day would approximately the maximum individual safe Se intake. For safety, 400 micrograms is again proposed as the Maximum Safe Daily Dietary Se Intake. Problems inherent in this estimation have been discussed.

A serosurvey using enzyme-linked immunosorbent assay for antibodies against poultry pathogens in ostriches (Struthio camelus) from Zimbabwe

Horseradish peroxidase-conjugated goat anti-ostrich IgG was raised and used in commercial enzyme-linked immunosorbent assay kits to detect antibodies reactive with 11 poultry pathogens in sera from 149 ostriches from nine farms around Zimbabwe. Antibodies were detected to turkey rhinotracheitis virus (99%), Newcastle disease virus (23%), avian reovirus (19%), infectious bursal disease virus (15%), avian encephalomyelitis virus (15%), Mycoplasma gallisepticum and/or M. synoviae (11%), reticuloendotheliosis virus (10%), Salmonella enteritidis (8%), avian leukosis virus (3%), infectious bronchitis virus (2%), and Pasteurella multocida (< 1%). Although evidence of prior infection with turkey rhinotracheitis and newcastle disease virus was present on all farms tested, there was marked variation between farms in the prevalence of exposure to other poultry pathogens.

Quantitation of prostate-specific acid phosphatase in prostate cancer: reproducibility and correlation with subjective grade

In this study, we quantitatively evaluated the intensity and extent of prostate-specific acid phosphatase in immunocytochemically stained prostate carcinoma tissue sections by using a dual-wave-length-based image processing technique. Tissue sections were doubly stained in a standard way, i.e., prostate-specific acid phosphatase was immunocytochemically labeled by peroxidase-antiperoxidase (PAP) technique using diaminobenezidene (DAB) as the substrate and hematoxylin as a nuclear counterstain. Statistical analysis in this study indicated that the quantitative measures of the prostate-specific acid phosphatase staining (PAP-DAB) are reproducible. We found that the quantitative intensity was generally proportional to the subjective intensity (graded as 1 to 4+) of PAP-DAB. Although the quantitative extent measurements compared with the subjective estimates of the percentage of tumor showing staining with PAP-DAB had a similar tendency, there were significant overlaps between extent of tumor staining falling in the mid-ranges. Because subjective grading of immunocytochemical prostate-specific acid phosphatase has been thought to be a useful marker of tumor differentiation in patients with prostate carcinoma, we also evaluated the relationship of the quantitative measures of PAP-DAB staining to other predictors of patient outcome, including histologic grades (Gleason score and MD Anderson grading scheme) and clinical stage. We confirmed that quantitative intensity and extent of PAP-DAB staining were independent of histologic grades and stage, just as the subjective measures of intensity and extent were found to be. Possible explanations of this lack of correlation are discussed.

Direct observation of the effect of autoreceptors on stimulated release of catecholamines from adrenal cells

The direct effect of alpha 2-autoreceptors was studied by measuring the effects of piperoxan, an alpha 2-autoreceptor antagonist, and clonidine, an agonist on catecholamine exocytosis, from single bovine chromaffin cells in culture. Catecholamine release was elicited by stimulation with 100 microM nicotine and was monitored electrochemically with a carbon-fiber microelectrode placed adjacent to the cell. These electrodes allowed the number of exocytotic release events to be monitored and reported as total charge for release following a specific stimulus. Repeated stimulation with 100 microM nicotine showed that total release caused by the second exposure to nicotine was 32% of the first, and release caused by the third exposure to nicotine was 80% of the second. Total release of catecholamine increased significantly after application of 20 microM piperoxan relative to a control application of balanced salt solution. Application of 20 microM piperoxan alone did not cause release. After the cells were incubated in culture medium containing 20 microM clonidine, a significant decrease in nicotine-stimulated catecholamine release was observed. These results confirm that there are autoreceptors on chromaffin cells and, when relatively high levels of catecholamine are released, the catecholamine stimulates the alpha 2-autoreceptors, which inhibits subsequent release through a negative feedback mechanism. In addition to piperoxan, the sympathomimetic drug amphetamine also increases quantal release after application of nicotine. Amphetamine increases the extracellular concentration of catecholamine, and these data appear to indicate that at least part of the pharmacology of amphetamine might involve blocking catecholamine autoreceptors.

Isolation and characterization of Bsk, a growth factor receptor-like tyrosine kinase associated with the limbic system

Neuronal degeneration has been shown to be involved in various neurological disorders. Growth/trophic factors and their receptors are known to be important for the regeneration and survival of neurons. We report here the molecular cloning of a receptor-like protein tyrosine kinase, bsk, (for brain specific kinase). Bsk is highly related to the eph/elk receptor-like kinase family members. Northern blot analysis shows that it is expressed specifically in the brain, with no expression detected in adult heart, spleen, lung, liver, skeletal muscle, and kidney. In situ hybridization analysis of adult mouse brain sections indicates that bsk is expressed at high levels in the hippocampus, tenia tecta, indusium griseum, and the piriform cortex, major components of the limbic system that are important for learning and memory. In addition, elevated levels of expression are found in other areas of the limbic system such as the amygdala, medial septum, and nucleus of the diagonal band, and in the olfactory bulb, which has close connections to the limbic system. The highest level of expression is found in the CA3 region of the hippocampus and the pyramidal cell layer of the piriform cortex. In 16.5 day mouse embryos, bsk is expressed predominantly in the primordial cortex of the telencephalon. An antibody against a C-terminal peptide of bsk recognized a 105 kD protein in the 16.5 day embryonic head extract. Our analysis shows that bsk is a growth factor receptor-like protein tyrosine kinase and that its greatest expression in the adult brain is associated with components of the limbic system.

[A study on the transcriptional expression of oncogenes in human primary brain tumors]

The c-myc, L-myc, N-myc, Ha-ras, c-fos, and v-erbB oncogenes were used as probes to detect the total RNA of 5 cases of normal human brain tissues and 29 cases of brain tumor tissues by RNA dot hybridization analysis. The results showed that the increasing expressions of cerbB and c-fos were the highest, being 88.2% and 82.4%, respectively, the next was c-myc with an increased expression of 46.1%; the increasing expressions of L-myc (29.3%) and N-myc (31.6%) were observed in a few samples only. There was no significant difference of Ha-ras gene expression between normal brain and brain tumor. In addition, we observed the increasing expression of more than one oncogene in one sample. These results suggest that c-erbB and c-fos oncogenes may play an important role in the pathogenesis of human primary brain tumors, and that multiple genetic changes are implicated in genesis of human brain tumors.

Etiological investigation of acute post-transfusion non-A, non-B hepatitis in China

The etiology of acute post-transfusion hepatitis (PTH) non-A, non-B (NANB) in China was investigated with the combination of advanced techniques, including a second generation of enzyme immunoassay for detection of the antibodies to hepatitis C virus (anti-HCV), a reverse transcription and nested polymerase chain reaction (RT-nPCR) for HCV RNA, and a PCR for hepatitis B virus DNA. Of the 57 patients who were diagnosed as acute PTH-NANB, 46 (80.7%) were positive for anti-HCV and 41 (71.9%) had HCV RNA. Combining together, 53 (93.0%) were seropositive for anti-HCV and/or HCV RNA. Surprisingly, 18 of these with HCV markers were also positive for HBV DNA, although they were negative for HBsAg, suggesting that a portion of the patients with acute PTH NANB were coinfected by both HCV and HBV. In addition, 4 (7%) of the patients with acute PTH-NANB had no detectable HCV and HBV markers with the use of the above-mentioned techniques. These results indicate that etiologic agents(s) other than HCV and HBV may also cause acute PTH-NANB or that the current techniques may still not be sensitive enough to detect trace levels of HCV and HBV markers.

pp39mos is associated with p34cdc2 kinase in c-mosxe-transformed NIH 3T3 cells

We investigated the possible interactions between pp39mos and p34cdc2 kinase in NIH 3T3 cells transformed by c-mosxe. pp39mos is coprecipitated with p34cdc2 when using either anti-PSTAIR antibody or p13suc1-Sepharose beads. Likewise, p34cdc2 is coprecipitated with pp39mos when using anti-mos antibody. However, pp39mos was not present in histone H1 kinase-active p34cdc2 complexes precipitated with anti-p34cdc2 C-terminal peptide antibody even during metaphase of the cell cycle. The molar ratio of p34 to pp39mos in the p13suc1 complex is approximately 2:1. Consistent with the tight association between pp39mos and tubulin, tubulin was also present in equivalent amounts with pp39mos and p34 in the p13suc1 complex. This pp39mos-p34cdc2-tubulin complex may be important in transformation by the mos oncogene.

Correlation between the prevalence of serum HBV DNA and immunoserologic HBV markers in the subjects with or without hepatitis

The prevalence of serum HBV DNA, detected by polymerase chain reaction, and that of immunoserologic HBV markers (HBsAg, HBeAg, anti-HBs, and anti-HBc), determined by immunoassays, were compared among three groups of subjects: (A) chronic active hepatitis B patients, (B) chronic asymptomatic HBV carriers, and (C) normal individuals. Except five of the normal individuals, all of the subjects are positive for anti-HBc while some of them were also positive for other immunoserologic HBV markers, such as anti-HBs, HBsAg, and HBeAg. Serum HBV DNA were detected in 81% in group A, 52% in group B, and 20% in group C. In both group A and B, serum HBV DNA were detected in all the subjects with anti-HBc+/HBsAg+/HBeAg+. However, the percentage of seropositive HBV DNA in the subjects with anti-HBc+/HBsAg+ in Group A was much higher than that in Group B. Interestingly, the percent of serum HBV DNA+ in the individuals with anti-HBc+ only was markedly higher than that in the subjects with anti-HBc+/anti-HBs+ in both Group A and C, suggesting that anti-HBs may play a role in the inhibition of HBV replication and clearance of HBV virion from blood. Above serological profiles will provide important information concerning the significance of serum HBV DNA detection in judgement of HBV replication in the individuals with or without HBV infection. Cautions should be taken to clarify those so called normal individuals who have no symptoms of hepatitis B, no HBsAg in the sera and normal transaminase, but have HBV replication in their bodies.

Quantitative peroxidase-antiperoxidase complex-substrate mass determination in tissue sections by a dual wavelength method

The aim of this study was to develop a method of quantitating prostate-specific acid phosphatase (PSAP) in histologic sections of prostate tumor tissue labeled with the peroxidase-antiperoxidase (PAP) complex technique using diaminobenzidine (DAB) as a substrate. Studies of PAP-DAB- and hematoxylin-stained prostate tissue sections were performed with a black-and-white, computerized microscope image system. The mass of brown reaction product generated in PAP-DAB staining was the indicator of PSAP intensity. The mass of brown reaction product was determined by using a dual wavelength method in which two 10-nm bandpass filters, peaked at 450 and 510 nm in wavelength, were used. The wavelength-dependent ratio of mass absorptivity of PAP-DAB stain (brown product) and that of hematoxylin (blue product) were estimated at wavelengths of 450 and 510 nm by using slides stained with only PAP-DAB or hematoxylin. The accuracy of the mass measurements, investigated by relating the measurement to the true mass of the brown PAP-DAB product, is reported. There was no significant difference between the measurements at magnifications of 10x, 20x, 40x or 60x in the reproducibility investigation. The PSAP stain intensity was quantitatively determined by the difference of the PAP-DAB stain mass per pixel between the tumor and normal cell region. The relationship between the objective measurement and the conventional subjective grades is presented.

[Allergic asthma in Hubin rural area of Wujiang County in Suzhou]

An epidemiological investigation of allergic asthma was conducted in Hubin rural area of Wujiang county in Suzhou in 1984-1985. The prevalence rate found to be 7.8% (312/39951). The patients were seen in an Allergic Asthma Clinic (AAC) or found by village doctors under the guidance of a specialist from the AAC. They were treated with desensitizing therapy of acupoints and followed up for more than two years. It was found that after the therapy the seasonal attack of allergic asthma disappeared, the number of patients coming to the AAC for treatment decreased and 90% patients had their symptoms greatly improved.

Hepatitis B virus DNA in sera of virus carriers positive exclusively for antibodies to the hepatitis B core antigen

The prevalence of serum HBV DNA in individuals positive for anti-HBc alone was determined by the polymerase chain reaction in two groups with endemic HBV infection from Canton (group A) and Hainan (group B), provinces of China. Twenty-one out of 294 individuals in group A (7.2%) and 193 out of 1995 in group B (9.7%) were positive for anti-HBc but negative for other markers of ongoing or past HBV infection (HBsAg and anti-HBs). HBV DNA was detected in 6/21 sera in group A (28.6%) and 68/193 in group B (35.2%) in their initial serum specimen. One of the six HBV-DNA-positive individuals in group A became negative after 6 months and four of the 58 positive in group B became negative at 4 years of follow-up. All of the individuals remained positive for anti-HBc and negative for anti-HBs, but one of them became positive for HBsAg on follow-up. None of the anti-HBc- and HBV-DNA-positive subjects had symptoms of liver diseases. They were, therefore, defined as chronic asymptomatic HBV carriers with undetectable HBsAg. This type of carrier should be added to the typical HBsAg-positive carrier, who constitutes about 10-15% of the general Chinese population, to give a more complete estimate of asymptomatic HBV carriers in China.

[Effects of verticillatine on cerebral blood flow, cerebral vascular resistance and blood pressure in anesthetized dogs and cats]

The effects of verticillatine (Ver), hexamethonium (Hex) and nimodipine (Nim) on mean arterial pressure (MAP), cerebral blood flow (CBF) and cerebrovascular resistance (CVR) were determined in pentobarbital anesthetized animals using the method of electromagnetic flow meter in dogs and hydrogen clearance in cats. Ver or Nim iv induced significant reduction of MAP and CVR. CBF was increased in dogs and unaltered in cats. The Hex treated dogs and cats exhibited a fall of MAP and CBF with enhancement of CVR. In cats after middle cerebral artery occlusion (MCAO), regional cerebral blood flow (rCBF) was reduced from 190 +/- 70 to 90 +/- 20 ml.kg-1.min-1. Ver and Nim iv caused similar changes of MAP and CVR to those before MCAO. The results suggest that Ver and Nim may have vasodilation effect and improve the cerebral circulation. Thus, they would be beneficial to patients suffering from hypertension.

[Pulsed-wave Doppler ultrasound evaluation of flow velocity waveforms of fetal umbilical artery and uterine artery as predictors of neonatal outcome]

A pulsed-wave doppler ultrasound system was used to record arterial flow velocity time waveforms from the fetal umbilical artery (UmA) and the branches of the uterine artery (UtA) in the placental bed in term pregnancies. The systolic-diastolic ratio (S/D) of flow velocity was measured as an index of peripheral resistance in the placental bed. The UmA S/D ratio was measured in 123 pregnant women between 37- less than 42 gestational weeks and the UtA S/D ratio was measured in 121 of them simultaneously. The cutoff value of an abnormal UmA S/D ratio was 3.0 or higher, and UtA S/D ratio 2.5 or higher. Furthermore, the neonatal poor outcome was observed more frequently in both the abnormal ratio groups than in both the normal ratio groups. The sensitivity of the UmA, and UtA S/D ratios to predict an adverse neonatal outcome was 72.7%, 27.3%, respectively. The data showed the abnormal UmA S/D and abnormal UtA S/D ratios were associated with the neonatal poor outcome, but the former was the better test for screening for adverse neonatal outcome.

[Identification of HBV infection in HBsAg-negative chronic active hepatitis with polymerase chain reaction]

To explore the etiological agent(s) of HBsAg negative chronic active hepatitis, serum HBV DNA was tested in thirty-six of such cases with polymerase chain reaction. In total, viral DNA was detected in 24 cases (67%), including 11 of the 12 cases with positive anti-HBc alone, four of the nine cases with positive anti-HBs and nine of the 15 cases without any HBV markers. The results suggest that in cases of HBsAg-negative chronic active hepatitis, the etiology may still be hepatitis B virus, especially in cases with positive anti-HBc. Furthermore, the cause of activated histology might be due to viral replication.

Changes in intracellular calcium of porcine sperm during in vitro incubation with seminal plasma and a capacitating medium

The intracellular free Ca2+ concentration in ejaculated, porcine sperm was determined with a fluorescent, Ca2(+)-specific probe, Fura 2. Following suspension of sperm in a medium capable of sustaining capacitation and the acrosome reaction, the intracellular [Ca2+] increased from an initial value of about 75 nM to a peak value of 130 nM, after about 4 to 5 h of incubation. Within this period of time, a peak value of 246 nM was attained when sperm was incubated in seminal plasma. Ca2+ uptake is presumably not associated with membrane potential-dependent channels. The results indicate that a pronounced increase in intracellular free Ca2+ occurs towards the end of the incubation period when rather synchronous acrosome reactions take place in the sperm population, either in capacitating medium or in seminal plasma.

[On the establishment and development of a resource of Chinese medicinal materials]

The author attempts to elucidate the concept, properties, tasks, scope, historical background and some problems in developing the Resource of Chinese Medicinal Materials, a comprehensive subject which deals with the development, utilization and management of resources of Chinese medicinal materials. The major aim is to provide more and better Chinese crude drugs for clinical and pharmaceutical purposes.

Studies of safe maximal daily dietary Se-intake in a seleniferous area in China. Part II: Relation between Se-intake and the manifestation of clinical signs and certain biochemical alterations in blood and urine

Selenosis occurs in areas of Enshi county because of the high Se content of the food. Morphological changes in finger-nails were used as the main criterion for clinical diagnosis of selenosis. Pathological nails were observed to occur almost only in adults, not at all in young children and very seldom in teenagers. Symptoms of selenosis in susceptible patients were found at or above an Se-intake of 910 micrograms/d, corresponding to a blood Se level of 1.05 mg/L. There was no evidence for an increased susceptibility to dental caries due to high Se consumption, and an increase in Se-intake seems unlikely to reduce the beneficial effects of fluoride on caries. No abnormalities of liver or heart were seen by supersonic B or electrocardiographic examinations. The biochemical investigations showed that with increasing whole blood Se the ratio of plasma Se to erythrocyte Se tended to decrease. As Se-intake increases to over 750 micrograms daily, the ratio decreases to near a minimal level. Reduced glutathione in whole blood decreases within a blood Se range of 1.01 to 2.28 micrograms in the high Se area. The amount of trimethylselenonium ion excreted in urine increased with the increase of urinary Se. Cases with prolonged prothrombin time occurred as blood Se increased to a level above 1 mg/L. The white blood cell count also increased significantly. Quantitative values were obtained only for ratio of plasma-Se to erythrocyte-Se for prothrombin time and for maintenance of nail Symptoms of susceptible patients. The overall results indicated that a daily Se-intake of 750-850 micrograms [corrected] might be the marginal level of safe intake. When other variable factors are also taken into consideration a daily Se-intake of 400 micrograms [corrected] is suggested as the maximum daily safe intake. At this level of Se-intake the corresponding approximate tissue Se levels are: whole blood 0.559 mg/L, plasma 0.327 mg/L, urine excretion 173 micrograms/d, hair 3.60 mg/kg, toe-nails 4.25 mg/kg, and finger-nails 4.70 mg/kg.

Studies of safe maximal daily dietary selenium intake in a seleniferous area in China. I. Selenium intake and tissue selenium levels of the inhabitants

Studies of marginal safe Se-intake have been carried out in a seleniferous section of China since 1985. Three areas with low, medium and high Se levels were selected for this study. The respective average daily Se-intake (mean +/- SE) was 70.5 +/- 4.8 micrograms, 194.7 +/- 22.9 micrograms and 1438.2 +/- 76.3 micrograms for males, and 62.0 +/- 3.6 micrograms, 198.1 +/- 23.8 micrograms and 1238.5 +/- 64.6 micrograms for females (average body weight: male 55 Kg, female 53 Kg). When the increasing rate of Se-intake was compared with the corresponding tissue-Se levels it was found that the whole blood Se-level reflected more closely the physiological range of Se-intake, while at higher Se-intakes it became less sensitive than the levels in hair, finger-nail and toe-nail, which were comparable to the sensitivity of urine. It is suggested that hair, finger- and toe-nail may all act as excretory organs when excess amounts of Se are ingested. Hair- and blood-Cd are somewhat higher in residents of the high Se area, but whether they have influenced human Se-metabolism at the high level of Se-intake is not yet known. Significant correlations on log-log plots were obtained between levels of daily Se-intake and whole blood r = 0.878), breast milk (r = 0.899) and 24-h-urine (r = 0.859). Highly significant correlations on log-log plots between levels of tissue were also obtained: urine Se--plasma Se (r = 0.968), whole blood Se--hair Se (r = 0.952), fingernail Se--toenail Se (r = 0.919), hair Se--fingernail Se (r = 0.914), hair Se--toenail Se (r = 0.891), whole blood Se--toenail Se (r = 0.849) and whole blood Se--fingernail Se (r = 0.836). The highly significant correlations found between the Se-intake and the tissue-Se level, and also between the Se levels of various tissues, could possibly conveniently be used to convert the known tissue-Se level to the corresponding Se-intake. Taken together with the wide range of Se-intakes and corresponding tissue-Se levels this would provide the necessary conditions for studying the marginal and maximal safe Se-intakes in humans.

A dye release assay for determination of lysostaphin activity

We describe a method for determination of lysostaphin activity using Remazol Brilliant Blue R (RBB)-dyed staphylococcal cells or RBB-dyed staphylococcal peptidoglycan as substrate. The dyed substrates are easy to prepare and are stable for at least 6 months. Soluble hydrolytic products released by lysostaphin are measured spectrophotometrically at 595 nm after the insoluble substrate is removed by filtration or centrifugation. The dye release assay is more sensitive and more accurate than the previously described turbidimetric assay.

(-)-Gossypol: an active male antifertility agent

The enantiomers of gossypol have been resolved by preparative HPLC of diastereomeric Schiff's base derivatives on a chiral bonded phase. Whereas (+)-gossypol has previously been reported to be inactive, (-)-gossypol is now shown to be active as a male oral antifertility agent in hamsters.