Bone marrow derived cells for brain repair: recent findings and current controversies

Adult stem cells were once thought to produce only the cell lineages characteristic of the tissues in which they reside. Recent studies suggest that cells derived from one adult tissue can be reprogrammed to change into cellular phenotypes not normally found in that tissue. Bone marrow (BM) derived cells have been demonstrated to differentiate into multiple lineages, including glial cells and neurons, both in vivo and in vitro. This unexpected plasticity of BM cells occurs not only under experimental conditions, but also in humans following BM transplantation. As a result, BM transplantation has emerged as a novel approach to enhance neural regeneration and restore injured brain tissue. Several research teams have reported that transplanted BM cells can differentiate into neural derivatives; indeed, some of these cells were capable of integration into the host brain, where they promoted functional recovery after brain injury. Other researchers conducting similar studies were unable to find any evidence of neural differentiation, concluding that differentiation 'from marrow to brain' is not a common phenomenon. More recently, two papers in Nature also cast doubt on the plasticity of adult stem cells, suggesting that the acquisition of different identities by grafted BM cells may merely reflect their fusion with host cells. Reasons for the wide discrepancies among findings in current BM stem cell research are unclear, making it difficult to understand the mechanisms by which transplanted marrow stem cells provide therapeutic benefit. Here, we summarize recent findings on this subject, and address some of the major controversies that have marked the evolution of adult stem cell research.

[Field trials on the efficacy of albendazole composite against intestinal nematodiasis]

AIM

To study the anthelmintic effect of albendazole composite (containing 67 mg of albendazole and 83.3 mg base of pyrantel pamoate per tablet).

METHODS

A randomized controlled study was carried out to compare the efficacy of a single dose of 3 or 2 tablets of albendazole composite versus a single dose of 400 mg of albendazole or 10 mg base/kg of pyrantel pamoate for treatment of intestinal nematodiasis including 1,864 cases infected with hookworm, 1,568 cases infected with Ascaris, 1,785 cases infected with Tricuris trichiura and 373 children infected with Enterobius vermicularis.

RESULTS

In adults, the egg negative conversion rate of a single dose of 3 or 2 tablets of albendazole composite reached 65.0% and 52.7% for hookworm infection (P < 0.01), 100% and 100% for Ascaris infection, and 26.5% and 19.2% for Trichuris infection (P < 0.01), respectively. There were significantly better effect against hookworm with 3 tablets of albendazole composite than that with single albendazole or pyrantel pamoate (65.0% vs. 47.6% and 38.5%, P < 0.01). The effect of 2 tablets of albendazole composite against hookworm was also higher than that of single pyrantel pamoate (P < 0.01) and equal to single albendazole but the anthelmintic effect against Trichuris infection was lower than that of single albendazole (19.2% vs. 26.5%). In 2-6-year-old children, the effect of 1.5 tablets of albendazole composite against Enterobius vermicularis infection showed an egg negative conversion rate of 100% which was higher than that of single pyrantel pamoate (100% vs. 83.0%, P < 0.01). The worm collection data showed that the worm-expelling action of albendazole composite was much more rapid than that of albendazole. There were no adverse effects of albendazole composite on blood picture, liver or renal function and ECG. The side effect of both 3 and 2 tablets of albendazole composite was mild and transcient.

CONCLUSION

Albendazole composite exhibits a synergistic effect of both albendazole and pyrantel pamoate.

[Exploration on conception of preventive medicine in Dong nationality]

On the basis of materials of folk medicine and traditional medical experience collected on the spot, the preventive methods in Dong nationality and its national customs and habits are analysed and systemitized preliminary exploration is made on its preventive conception, thus providing a valuable basis for systematizing the medical system of Dong medicine.

Ggamma in dictyostelium: its role in localization of gbetagamma to the membrane is required for chemotaxis in shallow gradients

G-protein-mediated signal transduction pathways play an essential role in the developmental program of the simple eukaryotic organism Dictyostelium discoideum. Database searches have yielded 11 Galpha-subunits, a single Gbeta-subunit, but no Ggamma-subunits. We report here the purification, cDNA isolation, and functional analysis of a Ggamma-subunit. Like Gbeta, the Ggamma appears to be unique and hybridization studies show that Ggamma and Gbeta are expressed in parallel during development. Species-wide sequence comparisons of Ggamma-subunits and gamma-like domains of RGS proteins reveal short stretches of highly conserved residues as well as the common CXXL motif at the COOH-terminal of Ggammas that target Gbetagammas to plasma membrane. Overexpression of a CSVL-deleted Ggamma (GgammaDelta) in wild-type cells shifts Gbetagamma to the cytosol and selectively impairs certain G-protein-mediated signal transduction pathways. These cells are able to respond to increments in the stimulus, but are unable to sense chemoattractant gradients. They neither move directionally nor recruit PH-domains to their leading edge. Thus, a full complement of membrane-tethered Gbetagamma is required for sensing shallow gradients, but is not essential for responses to increments in extracellular stimuli.

Construction and application of phenytoin anion-selective electrode based on bulk acoustic wave (BAW) sensing technique

This paper describes the construction of an anion-selective bulk acoustic wave (BAW) sensor for the direct determination of phenytoin sodium for the first time. Based on the sensitive mass response of a piezoelectric quartz crystal (PQC) and selective adsorption-desorption across the modified film, the BAW sensor was fabricated by coating a polyvinylchloride (PVC) film containing activator on one side of a PQC. The method was found to be sensitive, rapid and easy to handle without pretreatment of the sample. The logarithm of the frequency shift of the PQC shows a linear relationship to the logarithm of the concentration of phenytoin over the range 6.7 x 10(-8)-8.0 x 10(-4) M with a detection limit of 1.0 x 10(-8) M at pH 10.0. Recoveries were in the range 98.5-102.0%. Influencing factors were examined and optimized. Also discussed is the preliminary application of the phenytoin BAW sensor in serum and injection. The results for real samples obtained by the proposed method agreed with those obtained by conventional methods.

Determination of carbonyl compounds in air by electrochromatography

A new analytical procedure based on electrochromatography was developed for the separation and quantitation of 14 aldehydes and ketones (formaldehyde, acetaldehyde, acetone, acrolein, propionaldehyde, butanone, crotonaldehyde, isobutyraldehyde/butyraldehyde, 2-pentenaldehyde, isovaleraldehyde, valeraldehyde, benzaldehyde and hexanaldehyde) in ambient air currently to be regulated by the Hong Kong Environmental Protection Department. A volatile mobile phase using ammonium acetate compatible with mass spectrometry detection was developed and optimized as follows. Methanol: acetonitrile: aqueous buffer (4 mM ammonium acetate) = 65:5:30% v/v. With electrokinetic injection at 5 kV for 2 s, aqueous buffer pH adjusted to 8, applied voltage controlled at 25 kV, and detection at 360 nm in a fused-silica column packed with 3 microm ODS, a satisfactory separation was obtained for the 14 carbonyl compounds investigated. The working ranges in acetonitrile solution were found to vary from 0.25 to 79 mg/L with a correlation coefficient greater than 0.99, detection limits from 0.10 to 0.63 mg/L, and precision (relative standard deviation, n = 3) from 2.3 to 9.2%. Under an air flow rate of 0.3 L/min for a sampling time of 1 h, the working ranges varied from 0.030 to 11,000 microg/m3 and detection limits from 0.011 to 0.084 microg/ m3. The method has been successfully applied to monitor three carbonyl compounds in four urban and rural sites in Hong Kong and gave hourly readings of three carbonyl compounds for all the sites investigated with a separation time less than 25 min.

[The optimal concentration of drinking water in eastern Guangdong]

OBJECTIVE

The objectives were to explore the optimal concentration of drinking water in Eastern Guangdong and to provide information for the health administrative department to set up the criteria for fluoride concentration.

METHODS

Totally 1237 9-17 and 35-44 years old residents in Eastern Guangdong who drinking water containing 0.1-2.5 mg/L fluoride were recruited to investigate the occurrences of dental caries and dental fluorosis. Their background information and perceived appearances of teeth were also recorded.

RESULTS

The major factor influencing dental fluorosis was fluoride concentration in drinking water. Dental caries decreased when the fluoride concentration increased but dental fluorosis also increased at the same time. It was showed by calculation that the Dental Fluorosis Index would be 0.4 and 0.6 when the fluoride concentration was 0.57 mg/L and 0.7 mg/L respectively. The acceptation to the severity of dental fluorosis among the study subjects was in accordance with the Dean's criteria.

CONCLUSION

It suggests that the optimal fluoride concentration in Eastern Guangdong is 0.57 mg/L and should not exceed the upper limit of 0.7 mg/L.

Ion-selective piezoelectric sensor for niacinamide assay in serum and urine

An ion-selective piezoelectric (ISP) sensor was successfully applied for the determination of niacinamide in serum and urine. By coating a polyvinylchloride membrane containing niacinamide-silicotungstate on one electrode of a thickness-shear mode piezoelectric quartz crystal, the ISP device can adsorb niacinamide selectively. The amount of coating applied to the crystal was calculated from the Sauerbrey equation by monitoring the frequency change. The logarithm of the frequency shift was linear with the logarithm of niacinamide concentration over the range from 1.0 x 10(-9) to 1.0 x 10(-3) M with a detection limit of 1.0 x 10(-9) M at pH 7.0. Influencing factors were investigated and optimized. The results for real samples obtained by the proposed method were in good agreement with those obtained by the conventional methods.

The human ARHI tumor suppressor gene inhibits lactation and growth in transgenic mice

ARHI is a novel imprinted tumor suppressor gene. To study its function in vivo, we have developed transgenic mice that overexpress ARHI. Offspring bearing the transgene had significantly lower body weights than did nontransgenic littermates. In addition, strong expression of the ARHI transgene was associated with greatly impaired mammary gland development and lactation, failure of ovarian folliculogenesis resulting in decreased fertility, loss of neurons in the cerebellar cortex, and impaired development of the thymus. Decrease in body size and defects in the mammary glands correlated with the level of transgene expression. Immunohistochemical analysis indicated that expression of prolactin (PRL), but not growth hormone, was lower in the pituitary glands of mice with defective mammary gland development. The defect in pregnancy-associated mammary tissue proliferation was associated with decreased serum PRL and progesterone levels. Moreover, lower levels of estrogen receptor and progesterone receptor were observed in postpartum mammary glands and in the ovaries of mice that overexpressed ARHI. Our data suggest that ARHI can inhibit PRL secretion and act as a negative regulator in murine growth and development.

Right ventricular function of patients with septic shock: clinical significance

OBJECTIVE

To understand the effect of right ventricular dysfunction on circulatory supportive therapy in patients with septic shock.

METHODS

25 patients with septic shock who were admitted consecutively to the intensive care unit (ICU) of Peking Union Medical College Hospital were observed prospectively. Hemodynamic profile of the left side and right side heart was monitored with right ventricular ejection fraction catheter and transthoracic echocardiography. Intramucosal pH (pHi) and oxygen delivery were also monitored to illustrate any relation with patient outcome.

RESULTS

Stroke volume index (SVI) and right ventricular ejection fraction (RVEF) were significantly higher in survivors than in nonsurvivors (P < 0.01 and < 0.05, respectively). The pulmonary vascular resistance index (PVRI) was significantly lower in survivors (P < 0.01). At the onset of shock, the left ventricular end-diastolic volume index (LVEDVI) of both groups was very low, and steadily increased in survivors but not in nonsurvivors. Left ventricular ejection fraction (LVEF) and systemic vascular resistance index (SVRI) decreased during treatment, which were not different in both groups. Right ventricular end-diastolic volume index (RVEDVI) increased in both survivors and nonsurvivors. Oxygen delivery of nonsurvivors was significantly lower than that of survivors. LVEDVI and RVEF were correlated with SVI in both survivors and nonsurvivors.

CONCLUSIONS

The impairment of right heart function may be more severe than that of left heart function in the patients with early septic shock. "Right heart priority" must be seriously considered in supportive treatment of patients with septic shock. The present treatment of septic shock has significant limitations, and even aggravates the existing cardiac dysfunction.

[The research progress of using electromagnetic technology in treatment of bone diseases]

In these years, the study of the bioeffects of electromagnetic fields (EMFs) has been listed as the national important task in the field of biological physics. Using EMFs to treat bone diseases is associated with electric technology, biology and medicine. Previous medical studies have shown that EMFs can stimulate healing in bone fractures. But the effects are still controversial and the mechanism is not yet clear. Therefore, it is necessary to carry out experiments in vitro at cellular and molecular levels. Research workers have been exploring the effects of EMFs on bone formation and metabolism. The suggestion of using EMFs in the treatment of osteoporosis and other osseous diseases has been put forward.

Localization of the G protein betagamma complex in living cells during chemotaxis

Gradients of chemoattractants elicit signaling events at the leading edge of a cell even though chemoattractant receptors are uniformly distributed on the cell surface. In highly polarized Dictyostelium discoideum amoebas, membrane-associated betagamma subunits of heterotrimeric guanine nucleotide-binding proteins (G proteins) were localized in a shallow anterior-posterior gradient. A uniformly applied chemoattractant generated binding sites for pleckstrin homology (PH) domains on the inner surface of the membrane in a pattern similar to that of the Gbetagamma subunits. Loss of cell polarity resulted in uniform distribution of both the Gbetagamma subunits and the sensitivity of PH domain recruitment. These observations indicate that Gbetagamma subunits are not sufficiently localized to restrict signaling events to the leading edge but that their distribution may determine the relative chemotactic sensitivity of polarized cells.

[Study on esophageal motility and its effect by EVL in patients with esophageal varices]

OBJECTIVE

To investigate the esophageal motility and its effect by EVL in patients with cirrhotic esophageal varices.

METHODS

LESP, LESR, PA, PD, PV and 24 h pH-monitoring were measured by PC Polygraf HR system in subjects of control and cases of esophageal varices before and after EVL.

RESULTS

In varices group, PA, PD, and PV were significantly abnormal in comparison with those in control group (P < 0.001, 0.01, 0.01). There were pathologic acid-reflux in patients with esophageal varices. After EVL, PA, PV and acid-reflux were significantly recovered.

CONCLUSION

Patients with esophageal varices suffer from the significant abnormal esophageal motility and acid-reflux. All of the abnormal changes can be recovered by EVL treatment.

Removal and degradation of phenol in a saturated flow by in-situ electrokinetic remediation and Fenton-like process

In this laboratory study, a sandy loam soil saturated with phenol solution was treated by in-situ electrokinetics-Fenton process incorporated with a permeable reactive wall of scrap iron powder (SIP). The soil was contaminated and saturated with aqueous phenol solution of 90-115 mg/kg in concentration. It was then placed in a soil cell. The soil cell was assembled with an anode reservoir and a cathode reservoir at its ends. A bed of SIP (1.05-32.69 g) was inserted in the soil cell at a distance of 5 cm from the anode reservoir compartment. For the test runs, 0.3% H(2)O(2) was used as the anode reservoir fluid, whereas de-ionized water was used as the cathode reservoir fluid. An electric gradient of 1 V/cm was applied to enhance the saturated flow in the soil cell for a period of 10 days. Experimental results have shown that the electroosmotic (EO) flow quantity decreased as the amount of SIP increased. This phenomenon was in good agreement with the results showing the value of EO permeability increased with a decreasing amount of SIP. Results also showed that throughout the test period the cumulative, consumed mass of H(2)O(2) in the anode reservoir increased as the amount of SIP decreased. On the other hand, the cumulative, increased mass of phenol in the cathode reservoir was found to increase with a decreasing amount of SIP. Meanwhile, the residual phenol concentration in the soil cell was found to decrease with a decreasing amount of SIP. When 1.05 g scrap iron powder was used, an overall removal and destruction efficiency of phenol of 99.7% was obtained. Therefore, it is evident that an in-situ combined technology of electrokinetic remediation and Fenton-like process is capable of simultaneously removing and degrading the phenol in a saturated flow.

Construction and analytical application of ion-selective piezoelectric sensor for atropine sulfate

The method describes the use of a piezoelectric quartz crystal (PQC) as a substitute for ion-selective electrodes. The approach is feasible when the membrane materials are electrically non-conductive and membrane potential measurements are consequently not possible. An ion-selective piezoelectric sensor sensitive to atropine sulfate was constructed by coating a PVC membrane containing activant on one the side of a PQC. On the basis of selective adsorption of atropine ions across the modified film and the sensitive mass response of PQC, the method exhibits a sensitive, rapid response and is easy to operate without pretreatment of the sample. The logarithm of the frequency shift gave a linear relationship with the logarithm of atropine sulfate concentration in the 1.0 x 10(-8)-1.0 x 10(-3) M range with a detection limit of 5.0 x 10(-9) M at pH 7.0. Recoveries were from 98.7-102.2%. Two activants, atropine tetraphenylborate and atropine dipicrylaminate, were synthesized and investigated. Influencing factors were also examined and optimized. The results for real samples obtained by the proposed method agreed with those obtained by conventional methods.

Treatment of carotid-cavernous sinus fistulas retrograde via the superior ophthalmic vein (SOV)

BACKGROUND

Carotid-cavernous sinus fistula is an old difficulty in neurosurgery. At present, the main way to deal with it is by embolizing the fistula via an arterial route. But if the fistula is small or supplied by several branches, it is difficult to embolize via an arterial approach.

METHODS

In this report, 21 patients with carotid-cavernous sinus fistulae were successfully cured by embolizing the fistula via the SOV approach.

RESULTS

All patients were cured, and there were no serious postoperative complications. Follow-up has been carried out in 19 cases for 8 months to more than 4 years; no recurrence manifested.

CONCLUSION

For carotid-cavernous sinus fistulae that cannot be embolized arterially, the superior ophthalmic vein route is an easy, safe, effective and promising approach.

[Chromatographic properties of tetradecylamine bonded stationary phase for reversed-phase liquid chromatography]

A novel bonded stationary phase, tetradecylamine bonded stationary phase (TABP), for reversed-phase HPLC was prepared by bonding 1-tetradecylamine to YWG-80 silica gel through 3-glycidoxypropyltrimethoxysilane. Hydrophobicity, selectivity and silanophilic activity of TABP were evaluated by using aromatic compounds as analytes and methanol-water as binary mobile phase. The orgainc components including acidic, basic and neutral aromatic analytes could be separated satisfactorily with excellent selectivity and peak shape. The relative retention alpha for ethylbenzene-toluene was found to be 1.66 and the asymmetry factors of basic aniline, p-toluidine and N,N-dimethylaniline were found to be 1.26, 1.21 and 1.10, respectively, with the V(methanol):V(water) = 55:45 mobile phase. Aniline was eluted before phenol due to the suppress of the ion exchange activity of residual silanols by the internal masking interaction.

Desensitization of G-protein-coupled receptors. agonist-induced phosphorylation of the chemoattractant receptor cAR1 lowers its intrinsic affinity for cAMP

Agonist-induced phosphorylation of G-protein-coupled receptors has been shown to facilitate the desensitization processes, such as receptor internalization, decreased efficiency of coupling to G-proteins, or decreased ligand affinity. The lowered affinity may be an intrinsic property of the phosphorylated receptor or it may be the result of altered interactions between the modified receptor and downstream components such as G-proteins or arrestins. To address this issue, we purified cAR1, the major chemoattractant receptor of Dictyostelium discoideum by a strategy that is independent of the ligand binding capacity of the receptor. To our knowledge, this represents the first successful purification of a chemoattractant receptor. The hexyl-histidine-tagged receptor was solubilized from a highly enriched plasma membrane preparation and purified by Ni2+-chelating chromatography. The protocol offers a simple way to purify 100-500 micrograms of a G-protein coupled receptor that can be targeted to the plasma membrane of D. discoideum. The Kd value for the purified cAR1 was about 200 nM, consistent with that of receptors that are not coupled to G-proteins in intact cells. In contrast, the affinity of phosphorylated cAR1, purified from desensitized cells, was about three times lower. Treatment of the phosphorylated receptor with protein phosphatases caused dephosphorylation and parallel restoration of higher affinity. We propose that ligand-induced phosphorylation of G-protein-coupled receptors causes a decrease in intrinsic affinity and may be useful in maintaining the receptor's sensitivity at high agonist levels. This affinity decrease may precede other processes such as receptor internalization or uncoupling from G-proteins.

[Immunohistochemical study of oral mucosa precancerous lesion and expression of cytokeratin of squamous cell carcinoma]

OBJECTIVE:The aim of this study was to investigate the expression and distribution of cytokeratin in oral mucosa. METHODS: Polyclonal cytokeratin antibody A(575) and ABC immunohistochemical technique were used. RESULTS: A tendency of progressive increase of cytokeratin expression was demonstrated from normal mucosa,mild moderate and severe dysplasia to squamous cell carcinoma. A notable overexpression was found in moderate,severe dysplasia and squamous cell carcinoma.The poor-differentiatin was related to the low reaction of A(575).The cases of strong reaction of A(575)were more advanced stages and metastasized to lymph nodes frquently. CONCLUSION: The overexpression of cytokeratin could play a role in potentiation the effects of genetic factors and activate oncogenes in the affected cells.The cumulative effects of the potentiation would be accelerate the progression of precancerous conditions.The reaction of A(575) was correlated with clinical stages and lymph node metastasis.

[Study on the psychological status of video display terminal operator]

Occupational psychological test designed by the Labour Hygiene Department of West China University of Medical Sciences was applied to survey the mental health of 516 video display terminal (VDT) workers and 396 control workers in Chengdu. The results showed that mental health level of VDT workers was higher than that of controls. In the somatic disorder, anxious and hostile are increased obviously. With the prolonging of operating hours per week, somatic disorders, depression and obsession are increased, especially when VDT operating time is more than 30 hours per week and operating on VDT is more than ten years. This indicates that the operating hours should not be more than 30 hours per week. It is found by multiple factors analysis of data that the main adverse effects on mental health are age and VDT operating time.

A novel cytosolic regulator, Pianissimo, is required for chemoattractant receptor and G protein-mediated activation of the 12 transmembrane domain adenylyl cyclase in Dictyostelium

Genetic analysis was applied to identify novel genes involved in G protein-linked pathways controlling development. Using restriction enzyme-mediated integration (REMI), we have identified a new gene, Pianissimo (PiaA), involved in cAMP signaling in Dictyostelium discoideum. PiaA encodes a 130-kD cytosolic protein required for chemoattractant receptor and G protein-mediated activation of the 12 transmembrane domain adenylyl cyclase. In piaA- null mutants, neither chemoattractant stimulation of intact cells nor GTPgammaS treatment of lysates activates the enzyme; constitutive expression of PiaA reverses these defects. Cytosols of wild-type cells that contain Pia protein reconstitute the GTPgammaS stimulation of adenylyl cyclase activity in piaA- lysates, indicating that Pia is directly involved in the activation. Pia and CRAC, a previously identified cytosolic regulator, are both essential for activation of the enzyme as lysates of crac- piaA- double mutants require both proteins for reconstitution. Homologs of PiaA are found in Saccharomyces cerevisiae and Schizosaccaromyces pombe; disruption of the S. cerevisiae homolog results in lethality. We propose that homologs of Pia and similar modes of regulation of these ubiquitous G protein-linked pathways are likely to exist in higher eukaryotes.

[P53 expression and clinical significance in oral squamous cell carcinoma]

P53 protein expression was investigated in oral squamous cell carcinomas and oral premalignant lesions by monoclonal antibody Do-1 and immunohistochemistry technique. 4 of 12 (33.3%) samples of severe epithelial dysplasia and 25 of 44 (56.8%) samples of squamous cell carcinoma expressed P53 protein while all the normal mucosa, mild and moderate epithelial dysplasia were negative. The P53 expression in carcinomas was associated with differentiation, lymph node metastasis and tumour stage. This result indicated that P53 genic mutation might be an early event in oral mucosa carcinogenesis and related to oral tumor progression. Detection of P53 protein probably has clinical significance in identifying the premalignant lesions of oral mucosa and predicting the prognosis of oral carcinomas.

A novel chiral stationary phase derived from L-proline for liquid chromatographic resolution of chiral compounds

The design and preparation of a novel chiral stationary phase (CSP) were described. The chiral resolutions of N-3,5-dinitrobenzoyl-DL-amino acid methyl esters were performed on the CSP. The selectivities were between 1.04 and 1.18. The applications of the CSP and the optimization of the chromatographic conditions will be further studied.

Determination of traces of hemoglobin by square wave stripping voltammetry at a silver microelectrode

An electrochemical method was developed for the determination of traces of hemoglobin (Hb) by adsorption square wave voltammetric stripping at a bare silver microelectrode. Under optimum conditions the proposed method provided a linear response over the hemoglobin concentration range 5 to 100 nmol/L. The detection limit was 3 nmol/L. The relative standard deviation was 4.5% for 6 successive determinations at 50 nmol/L Hb. Other chemicals present in the sample did not interfere.

Zinc-containing innervation of the subicular region in the rat

The subiculum is densely innervated by zinc-containing axonal terminals, but the cells of origin of those zinc-containing afferents have not previously been identified. In the present work the zinc-specific retrograde tracing method was employed to locate the zinc-containing neurons afferent to the subicular complex. Following microinfusions into the subicular region, the somata of zinc-containing neurons were found in the hippocampus, the pre- and para subiculum, retrosplenial, cingulate, and perirhinal cortices, and in the anterodorsal nucleus of the thalamus. The results show another component of the zinc-containing associational network that interconnects the cerebral cortex and amygdalohippocampal systems of the brain.

[Some biochemical indexes in white rabbit's blood affected by acute high intensity microwave]

Irradiation of white rabbits by 10, 50, 100 and 200 mW/cm2 microwave respectively can cause the disorder of protein metabolism, the abnormality of blood sugar, and the change of the activity of serum alpha-hydroxybutyrate dehydrogenase, lactate dehydrogenase, glutamic oxalacetic transaminase, glutamic pyruvic transaminase, acid phosphatase ect. These changes can be used as indexes in the evaluation of the effect of acute high intensity microwave exposure. The effect on the organism mainly depends on the intensity of exposure provided the dose of microwave remains the same.

A zinc-containing fiber system of thalamic origin

Zinc-containing neurons are cells that sequester zinc presynaptically and release it when active. Previously such neurons have been found almost exclusively in cerebrocortical and amygdalar regions. Here we describe a thalamo-cortical pathway that is zinc-containing, namely, the projection from the anterodorsal nucleus of the thalamus to the subicular cortex. The pathway was identified by the zinc-specific retrograde transport methods; its addition to the zinc-containing cerebral circuitry reinforces the association of the zinc-containing terminals with cortico-limbic systems.

[Physiological changes in middle-aged persons and old people before and after tennis competition]

An examination of medical and physiological changes before and after tennis competition was performed on 71 middle-aged persons and old people in order to know whether they were adapted to this intense match or not. The result was that in the male group 1 (50-59 yrs), the heart rate, respiration rate and blood pressure before and after the tennis game had no significant differences (P > 0.05), indicating that this group was fit for the tennis competition, in the male group 2 (60-69 yrs) and male group 3 (70-79 yrs), as age advances, the number of unfitness to this game was increased gradually; in the female group (50-59 yrs), 28.5% of them showed a marked increase in the heart rate after the competition. We think that when persons have an electrocardiogram showing a significant undue changes of the ST segment and T wave after the contest, they are not suitable to this violent competition. So the medical surveillance is very important for the old people to play violent games such as tennis. The periodical health examination should be done before any exercise event with emphasis on the cardiovascular system so that the old sportsman can choose the proper exercise item and take self-control during the exercise.

Effects of deglycosylation of human thyroperoxidase on its enzymatic activity and immunoreactivity

Thyroid peroxidase (TPO) is a glycoprotein enzyme which catalyses the iodination of thyroglobulin and the coupling of iodinated tyrosines. Human TPO (hTPO) is the microsomal antigen recognized by the autoantibodies in the serum of patients with autoimmune thyroid disease. An active detergent-solubilized immunoaffinity-purified hTPO was deglycosylated, either by peptide N-glycosidase F (PNGase F) or by endo-beta-N-acetylglucosaminidase H (endo H), and the enzymatic activity and immunoreactivity of the native and deglycosylated forms were compared. Electrophoretic controls and affinoblotting with concanavalin A showed that deglycosylation was not total and that it was more pronounced with endo H than with PNGase F. The enzymatic activity of hTPO was inhibited by endo H deglycosylation, but not by PNGase F deglycosylation; this inhibition was not due to aggregation and/or insolubilization of the molecule subsequent to deglycosylation. Immunoreactivity was monitored by enzyme-linked immunosorbent assay (ELISA) with 13 mouse monoclonal antibodies, rabbit polyclonal antibodies and antibodies from serum of patients with Hashimoto's thyroiditis. In contrast with enzymatic activity, immunoreactivity was not modified or was slightly enhanced (with four monoclonal antibodies) by deglycosylation. The results indicate that strong, if not total, deglycosylation induces a modification of the tertiary structure of hTPO, which affects the enzymatic site but does not modify markedly the epitopes implicated in the recognition of the molecule by the antibodies tested.

Effect of N-glycan removal on the enzymatic activity of porcine thyroid peroxidase

Active porcine thyroid peroxidase (pTPO) has been purified either by deoxycholate extraction followed by immunoaffinity purification (pTPO A) or by trypsin/digitonin extraction followed by ion-exchange and gelfiltration chromatography (pTPO B); pTPO A appeared as a full-length molecule, while pTPO B appeared as peptide fragments. Purified pTPO were deglycosylated either by peptide N-glycosidase F (PNGase F) or by endo-beta-N-acetylglucosaminidase H (endo H) treatment. Electrophoretic controls and affinity blotting with concanavalin A indicated that deglycosylation was not total and that pTPO was more efficiently deglycosylated by endo H than by PNGase F. The enzymatic activity of pTPO A, checked by guaiacol and iodide oxidation, was inhibited by PNGase F and endo H deglycosylation, while that of pTPO B was not. After deglycosylation, the apparent Km of pTPO A for guaiacol and iodide increased, while the Vmax for both substrates decreased. The state of aggregation of pTPO A before and after deglycosylation was checked by sucrose density-gradient centrifugation. Results indicated that this inhibition was not due to a loss of pTPO A solubility. These observations suggest that deglycosylation induced a modification of the tertiary structure of pTPO A which affected the active-site domain of the enzyme.

[A study of textile noise influence on maternal function and embryo-growth]

Ninety hundred seventy-eight female textile workers exposed to noise (greater than or equal to 85 dB (A)) were recruited as the subjects of observation group, and 402 nonexposed female workers were chosen as the controls (less than 75 dB (A)). According to noise level, the observation group was subdivided into three groups: group 1, 100-104 dB (A), 416 workers; group 2, 95-99 dB, (A), 310 workers; group 3, 85-94 dB (A), 252 workers. Non-conditional logistic regression model was used to exclude the effect of mixed factors, such as age and working life. The result showed that noise-exposure could have some adverse effect on reproductive function of women and embryo growth. The workers exposed to noise had significantly increased incidence rates for irregular menstrual cycle, dysmenorrhea, lumbago, hypertension in pregnancy, threatened abortion, spontaneous abortion, premature labour, dystocia and low birth weight of newborns. When the noise intensity heightened, the sorts of abnormal function of reproduction increased and the risk of incidence raised too. These demonstrated a dose-response relationship between the noise intensity and incidence rate. The noise-working life had significant effects on the incidence of hypertension in pregnancy and prematurity. Although the age had some influence, it was not statistically significant. In terms of the maternal function and embryo growth, the factors in order of risk are: noise intensity greater than working life greater than age.

Inhibition of N-glycan processing affects iodide organification in porcine thyroid cells

The N-glycan-processing inhibitors swainsonine (Sw) and deoxymannojirimycin (dMM) were used to study the influence of N-glycans on iodide organification in cultured porcine thyroid cells. Incubations with [125I]NaI were followed by determination of labeled trichloroacetic acid-insoluble material in culture media, follicular contents and cells. In controls, most of this material was in the follicular contents. With Sw and dMM, total acid-insoluble material was less than 10% of control. Iodide uptake was slightly inhibited and hydrogen peroxide release was not affected by inhibitors. Cell-surface thyroid peroxidase (TPO) activity, assayed by its ability to iodinate bovine serum albumin, was strongly inhibited. Pronase glycopeptide analysis indicated that with drugs the content in complex-type N-glycans was strongly decreased while that in hybrid or oligomannosidic type was increased. In conclusion, inhibition of N-glycan processing prevents iodide organification in cultured porcine thyroid cells by decreasing the recovery of cell-surface TPO activity.