Immunohistochemical localization of the D1 dopamine receptor in rat brain reveals its axonal transport, pre- and postsynaptic localization, and prevalence in the basal ganglia, limbic system, and thalamic reticular nucleus

D1 dopamine receptor localization was examined by immunohistochemistry using a polyclonal anti-peptide antibody which (i) immunoprecipitated a protein fragment encoded by a D1 receptor cDNA and (ii) on Western blots of solubilized striatal and hippocampal membranes recognized two proteins of approximately 50 kDa and 75 kDa, corresponding to reported sizes of D1 receptor proteins. Immunoreactivity overlapped with dopamine-containing pathways, patterns of D1 receptor binding, and mRNA expression. Staining was concentrated in prefrontal, cingulate, parietal, piriform, entorhinal, and hippocampal cortical areas and subcortically in the basal ganglia, amygdala, septal area, substantia inominata, thalamus, hypothalamus, and neurohypophysis. Prominent labeling was seen in the thalamic reticular nucleus, a region known to integrate ascending basal forebrain inputs with thalamocortical and corticothalamic pathways and in fiber bundles interconnecting limbic areas. In striatal neuropil, staining appeared in spines (heads and necks), at postsynaptic sites in dendrites, and in axon terminals; in the pars reticulata of the substantia nigra, labeling was prevalent in myelinated and unmyelinated axons and dendrites. These data provide direct evidence for the regional and subcellular distribution of D1 receptor protein in the brain and for its pre- and postsynaptic localization in the basal ganglia. The prominent immunoreactivity seen in the limbic system and thalamic reticular nucleus supports an important role for this receptor subtype in mediating integrative processes involved with learning, memory, and cognition.

Kinetic properties of aromatase mutants Pro308Phe, Asp309Asn, and Asp309Ala and their interactions with aromatase inhibitors

Mutant forms of aromatase cytochrome P-450 bearing modifications of amino acid residues Pro308 and Asp309 and expressed in transfected Chinese hamster ovary cells were subjected to kinetic analysis and inhibition studies. The Km for androstenedione for expressed wild type (11.0 +/- 0.3 nM SEM, n = 3) increased 4-, 25- and 31-fold for mutants Pro308Phe, Asp309Asn and Asp309Ala, respectively. There were significant differences in sensitivity among wild type and mutants to highly selective inhibitors of estrogen biosynthesis. 4-Hydroxyandrostenedione (4-OHA) a strong inhibitor of wild type aromatase activity (IC50 = 21 nM and Ki = 10 nM), was even more effective against mutant Pro308Phe (IC50 = 13 nM and Ki = 2.8 nM), but inhibition of mutants Asp309Asn and Asp309Ala was considerably less (IC50 = 345 and 330 nM and Ki = 55 and 79 nM, respectively). Expressed wild type aromatase and Pro308Phe aromatase were strongly inhibited by CGS 16949A (IC50 = 4.0 and 4.6 nM, respectively) whereas mutants Asp309Asn and Asp309Ala were markedly less sensitive (IC50 = 140 and 150 nM, respectively). CGS 18320B produced similar inhibition. Kinetic analyses produced Ki = 0.4 nM for CGS 16949A inhibition of wild type versus 1.1, 37 and 58 nM, respectively, against Pro308Phe, Asp309Asn and Asp309Ala. The results demonstrate significant changes in function resulting from single amino acid modifications of the aromatase enzyme. Our data indicate that mutation in Asp309 creates a major distortion in the substrate binding site, rendering the enzyme much less efficient for androstenedione aromatization. The substitution of Pro308 with Phe produces weaker affinity for androstenedione in the substrate pocket, but this alteration favors 4-OHA binding. Similarly, mutant Pro308Phe exhibits a slightly greater sensitivity to inhibition by CGS 18320B than does the wild type. These results indicate that residues Pro308 and Asp309 play critical roles in determining substrate specificity and catalytic capability in aromatase.

Functional domains of aromatase cytochrome P450 inferred from comparative analyses of amino acid sequences and substantiated by site-directed mutagenesis experiments

Several functional domains, especially the active site regions, in aromatase cytochrome P450 were inferred by alignment of amino acid sequences of the enzyme from five species, human, rat, mouse, chicken, and trout, and that of Pseudomonas putida cytochrome P450cam, whose x-ray structure has been determined (Poulos, T.L., Finzel, B.C., and Howard, A.J. (1987) J. Mol. Biol. 195, 687-700). The predicted functions of these domains have been evaluated by site-directed mutagenesis. Eighteen mutants, including seven new mutants, have been generated in this laboratory. The seven newly prepared mutants are Q123E, Q123H, T310S, T310C, R365K, R365A, and N delta 20 (a mutant without the first 20 amino acids). The preparation and characterization of these new mutants are described. The structural model described in this paper should be very useful for future structure-function studies of aromatase by site-directed mutagenesis.

Effect of exogenous sialylation of the lipooligosaccharide of Neisseria gonorrhoeae on opsonophagocytosis

Serum-sensitive Neisseria gonorrhoeae strains become serum resistant when grown in the presence of a sialic acid precursor, cytidine monophospho-N-acetylneuraminic acid. We examined the abilities of human neutrophils to phagocytose sialylated and nonsialylated gonococci and observed a decrease in the complement-dependent phagocytosis of sialylated gonococci compared with that of nonsialylated gonococci (50.7 versus 25.9% survival at 30 min). This decrease in opsonophagocytosis after sialylation may contribute to the pathogenicity of gonococcal infections.

[Effect of poly-saccharide sulphate on thixotropic properties of whole blood in patients with cerebral thrombosis]

Using Low shear 30 rheometer, we measured the thixotropic parameters of blood from 30 patients suffering from cerebral thrombosis. The result showed that the yield stress (tau 0), non-Newtonian contribution of viscosity (eta s-mu) and viscosity of plasma (eta p) were significantly higher than those in the control group. Those patients were randomly divided into two groups. Each group included 15 patients. The patients in group 1 and group 2 were treated with poly-saccharide sulphate (PSS) and DX40 respectively by intravenous drip for 14 days. The results showed that tau 0, A, (eta s-mu) were significant decreased in group 1 after treatment, but no significantly change in the thixotropic parameters was found in group 2 after treatment. The total curative rate in group 1 was higher than that in group 2. These results suggest that the patients with cerebral thrombosis had evidently increased degree of RBC aggregation. PSS could decrease the aggregation of RBC more significantly than DX40 did. It was probably one of the reasons why the therapeutic effect of PSS on cerebral thrombosis was better than that of DX40.

Reductions of neural activities to upper airway muscles after elevations in static lung volume

We evaluated the hypothesis that the tonic discharge of pulmonary stretch receptors significantly influences the respiratory-modulated activities of cranial nerves. Decerebrate and paralyzed cats were ventilated with a servo-respirator, which produced changes in lung volume in parallel with integrated phrenic activity. Activities of the facial, hypoglossal, and recurrent laryngeal nerves and nerves to the thyroarytenoid muscle and triangularis sterni were recorded. After a stereotyped pattern of lung inflation, tracheal pressure was held at 1, 2, 4, or 6 cmH2O during the subsequent ventilatory cycle. Increases in tracheal pressure caused progressive reductions in both inspiratory and expiratory cranial nerve activities and progressive elevations in triangularis sterni discharge; peak levels of phrenic activity declined modestly. Similar changes were observed in normocapnia and hypercapnia. We conclude that the tonic discharge of pulmonary stretch receptors is an important determinant of the presence and magnitude of respiratory-modulated cranial nerve activity. This reflex mechanism may maintain upper airway patency and also regulate expiratory airflow.

5-(p-aminophenyl)-1,2,3,4-tetrahydroxypentane, a structural component of the modified folate in Sulfolobus solfataricus

The partial characterization of the modified folate present in Sulfolobus solfataricus has been carried out. Separation of ethanol-water extracts of these cells on a DEAE-Sephadex column led to the isolation of a small amount of intact oxidized cofactor, which, when subjected to reductive cleavage with Zn-HCl, produced 6-methylpterin. This indicated that the modified folate in these cells contained a nonmethylated pterin linked, via a methylene group at the C-6 position of the pterin, to an arylamine, as is found in folate. Oxidative cleavage of intact reduced cofactor produced pterin and a single arylamine. The azo dye derivative of this arylamine was prepared and purified by chromatography on a Bio-Gel P-6 column. The resulting purified compound was shown to be readily hydrolyzed in dilute acid to the azo dye derivative of 5-(p-aminophenyl)-1,2,3,4-tetrahydroxypantane, which was, in turn, readily cleaved to 5-(p-aminophenyl)-1,2,3,4- tetrahydroxypentane by Zn-HCl reduction. The stereochemistry of the resulting 5-(p-aminophenyl)-1,2,3,4-tetrahydroxypentane was shown to be ribo, the same as that of the 5-(p-aminophenyl)-1,2,3,4- tetrahydroxypentane moiety found in methanopterin. The complete arylamine side chain of the modified folate thus contains 5-(p-aminophenyl)-1,2,3,4-tetrahydroxypentane attached, via an acid-labile bond, to a currently unidentified substituent. The modified folate present in S. solfataricus thus contains structural features common to both folates and methanopterin.

Radioiodinated anti-hepatocellular carcinoma (HCC) ferritin. Targeting therapy, tumor imaging and anti-antibody response in HCC patients with hepatic arterial infusion

Radioimmunoimaging and radioimmunotherapy with radioiodinated anti-(hepatocellular carcinoma ferritin) antibody (131I- or 125I-FtAb) have been applied in patients with primary liver cancer. A total of 41 patients with surgically unresectable hepatocellular carcinoma (HCC) and receiving hepatic artery ligation and cannulation during exploratory laparotomy were treated with this regimen by intrahepatic arterial infusion. Compared with the control group, a decline of serum alpha-fetoprotein (65.7% versus 42.9%) and shrinkage of tumor (68.3% versus 33.9%) were observed in the treated group, and a higher second-look resection rate (31.7% versus 5.1%) and longer survival (1-year: 61.0% versus 37.3%, 3-year: 25.0% versus 6.9%) resulted. The administration of antibody through a hepatic arterial catheter (n = 16) was compared with intravenous injection (n = 17) in terms of the tumor-imaging sensitivity in 33 patients with liver cancer. The results indicated that hepatic arterial infusion was superior to intravenous injection. The sensitivity 7 days after the administration was 100% in the i.a. group and 76.5% in the i.v. group, the uptake ratio of tumor to liver being 1.74 +/- 0.57 in the former and 1.34 +/- 0.29 in the latter. Furthermore, intrahepatic arterial infusion revealed a lower anti-antibody detection rate than intravenous injection (0/14 versus 4/11).

Liquid chromatographic separation of alkanesulfonate and alkyl sulfate surfactants: effect of ionic strength

The retention of alkanesulfonate and alkyl sulfate surfactants, which was determined on a reversed stationary phase as a function of mobile-phase ionic strength, is consistent with a double-layer type interaction at the stationary-phase surface. Increasing the mobile-phase ionic strength not only increases retention but also improves resolution because peak widths are significantly reduced. The type of cation provided by the ionic strength salt also enhances retention, reduces peak width, and improves resolution. Lithium hydroxide is an ideal electrolyte for the separation of multicomponent mixtures of alkanesulfonate and alkyl sulfate surfactants. When the column effluent is passed through a postcolumn anion micromembrane suppressor, the conductivity due to the electrolyte is minimized and conductivity detection is sensitive, yielding a detection limit of about 0.3 nmol of injected analyte for a 3:1 signal:noise ratio. Multicomponent alkanesulfonate and alkyl sulfate mixtures from C2 to C18 are baseline resolved by using a mobile-phase gradient whereby CH3CN concentration increases and LiOH concentration decreases.

In vitro and in vivo evaluation of microencapsulated porcine islets

To provide a plentiful supply of pancreatic islets for future clinical transplants into diabetic patients, the authors have developed a simple and consistent method of isolation of porcine islets. Both in vitro and in vivo studies demonstrated that the islets were viable and functional. Xenotransplants of 1.5 x 10(3) - 2.5 x 10(3) of microencapsulated porcine islets into diabetic mice resulted in restoration of normoglycemia in 13 of 18 experimental animals for up to 10 months. A xenograft of 50 x 10(3) microencapsulated porcine islets into a spontaneously diabetic monkey normalized hyperglycemia for more than 150 days. This experiment indicated that the transplantation of encapsulated porcine islets has great potential as a clinical treatment in diabetes mellitus.

Neurobiotin, a useful neuroanatomical tracer for in vivo anterograde, retrograde and transneuronal tract-tracing and for in vitro labeling of neurons

The biotin derivative, N-(2-aminoethyl) biotinamide hydrochloride, or Neurobiotin, has been shown recently to be a useful marker for intracellular and anterograde tracing. The properties of Neurobiotin as a tracer were further examined in this study by making pressure injections into different regions of the cerebral cortex or the rostral neostriatum of rats or by incubating striatal cells in culture with the tracer. Results showed extensive anterograde transport of Neurobiotin in cortical axons and terminals within the neostriatum 2-70 h after single or multiple cortical injections of the tracer. Similarly, profuse axonal projections to the medial portion of the globus pallidus were seen after an injection of Neurobiotin into the rostral neostriatum. Transneuronal labeling of medium-size neostriatal neurons was observed following injections of Neurobiotin into the prefrontal cortex. At the ultrastructural level, anterogradely labeled cortical axon terminals and transneuronally labeled neurons were readily identified in the caudate-putamen by the presence of both fine particulate and large punctate reaction products. Retrograde fillings of neurons resembling a Golgi-impregnation were seen in the ventral posterior complex of the thalamus after injections in the sensorimotor cortex. Neurons in the medial globus pallidus were also retrogradely labeled following tracer injections in the rostral caudate-putamen. Finally, Neurobiotin was readily and selectively taken up by striatal neurons in culture, where it extensively labeled somata and neurites. These results show that Neurobiotin is a versatile new tracer, which can be potentially useful for the study of neuronal organization in vivo and in vitro.

Rostral pontile mechanisms regulate durations of expiratory phases

Neural expiration can be divided into two phases. Phase I corresponds to the period of laryngeal adduction, whereas many spinal nerves reach peak discharge in phase II. The present studies evaluated the hypothesis that rostral pontile mechanisms contribute to determining the time of onset of spinal motoneuronal activities in phase II. In decerebrate and paralyzed cats, efferent activities were recorded from the phrenic nerve and from single fibers of the branch of the intercostal nerve innervating the triangularis sterni muscle. These activities were recorded in eupnea and apneusis; the latter was produced by cooling the rostral pons by a fork thermode. In eupnea, there was a delay between the rapid decline of phrenic discharge from peak levels and the commencement of activities of motoneurons of the triangularis sterni. This delay was significantly reduced in apneusis. Peak discharge frequencies of triangularis sterni motoneurons were the same in eupnea and apneusis. We conclude that rostral pontile mechanisms contribute significantly to defining the phases of neural expiration.

[Comparison of the effects of 4 psychiatric treatments on rat brain beta 5HT2 receptors]

Four psychiatric treatments, such as electro-convulsive treatment (ECT), insulin coma, electroacupuncture (EA) and antidepressants were given to rats chronically, and the brain cortex beta and serotonin2 receptors were measured. Comparing with their control groups we found that chronic ECT, insulin coma and EA have similar effect to down-regulate the specific coma and EA have receptor, but almost no effect on serotonin2 receptor. Antidepressants have various effects on brain monoamine receptors. The major effects of desipramine and imipramine were down-regulate B receptor, while of amitriptyline was down-regulate 5HT2 receptor. Our data suggested that different psychiatric treatment might effort their therapeutic effects mediated by different monoamine function in CNS.

Pathologic concentrations of interleukin 6 inhibit T cell responses via induction of activation of TGF-beta

Interleukin 6 levels are increased in a variety of clinical conditions including bacterial and viral infections, HIV infection, autoimmune diseases, certain neoplasias, and traumatic injury. In general, all these conditions are characterized by suppression of one or more manifestations of the immune response. Concentrations of IL 6 comparable to those found in the sera of immunosuppressed, thermally injured patients selectively inhibit T cell proliferative responses. This suppression is independent of IL 2-mediated responses, is dependent on macrophage activity, and is reversed by antisera specific for transforming growth factor-beta (TGF-beta).

[Study on ursodeoxycholic acid biotransformation by three strains of clostridia]

Using the improved TLC procedure, we measured the conversion rates of ursodeoxycholic acid(UDCA) from chenodeoxycholic acid (CDCA) by 3 strains of clostridia--C. perfringens HS-10, C. butyricum DL-20 and LQ-29 isolated. The orthogonal test was used to determine the optical conditions of biotransformation for HS-10. It was found that the conversion rate of UDCA by HS-10 was over 80% during 6-48 h in RCM medium containing 0.2 mmol/L CDCA. The UDCA conversion rates were still over 70% when the CDCA concentrations were as high as 0.8-1.0 mmol/L. In addition, the WW-BCP (Waste water from bean curd production) without any supplemental nutrients was preliminarily proved to be a potential inexpensive conversion medium.

[Long-term pathological findings of cerebral arteriovenous malformation after embolization]

Cerebral arteriovenous malformation was resected after embolization with Aron alpha and ZT plastic in 2 cases. Pathological examination in one patient revealed intravascular residual foreign-body giant-cell reaction and slight chronic inflammation in the adjacent parenchyma of the brain tissue 1.5 years after embolization. The other 1 patient was treated with embolization 4.5 years ago. No pathological changes were found either in the vessels or in the brain tissue. It is indicated that chronic inflammation after embolization with cyanoacrylate disapproved several years later.

Vestibular and cerebellar modulation of expiratory motor activities in the cat

1. The purpose of our investigation was to evaluate the hypothesis that components of the vestibular and cerebellar systems regulate efferent respiratory-modulated activities of cranial and spinal nerves. The hypothesis was based upon the observation that spinal neural activities during expiration are greatly altered subsequent to a change in posture. 2. In decerebrate and paralysed cats, efferent activities were recorded from the central cut ends of the phrenic nerve, intercostal nerve, branch of the intercostal nerve innervating the triangularis sterni, cranial iliohypogastric (abdominal) nerve and recurrent laryngeal nerve. 3. Animals were artificially ventilated. Those with intact vagi were ventilated by a servo-respirator which produced changes in lung volume in parallel with alterations in integrated activity of the phrenic nerve. Animals with bilateral vagotomy were ventilated with a standard respirator. 4. Aspiration of the entire cerebellar cortex did not produce alterations in levels of neural activities; the respiratory frequency was increased modestly. Following ablation of the ventrolateral portion of corpus medullare and cerebellar peduncles, expiratory activities of spinal nerves were completely eliminated whereas inspiratory activities were not greatly altered. Results were similar in animals having either intact or sectioned vagi. 5. Electrical stimulation or chemical stimulation by glutamate of regions of the ventrolateral cerebellum produced little change in respiratory neural activities except when these stimulations were within the infracerebellar nucleus. Stimulations in this nucleus caused pronounced increases in expiratory activities of spinal nerves. Neither inspiratory activities of spinal nerves nor inspiratory or expiratory activities of the recurrent laryngeal nerve were altered. Studies in animals having intact or sectioned vagi yielded similar results. 6. Bilateral lesions of neurons in the infracerebellar nucleus by injections of kainic acid in animals having intact or sectioned vagi caused an irreversible loss of expiratory activities of spinal nerves with neither inspiratory spinal activities nor inspiratory and expiratory laryngeal activities being altered. Similar findings were obtained following unilateral ablation of the infracerebellar nucleus in vagotomized cats. However, in cats with intact vagi, unilateral ablation of the infracerebellar nucleus produced only transient changes in either inspiratory or expiratory neural activities.(ABSTRACT TRUNCATED AT 400 WORDS)

Transsulfuration in archaebacteria

The transfer of sulfur from methionine to cysteine in the archaebacteria Sulfolobus acidocaldarius and Halobacterium marismortui was studied by feeding 34S-labeled methionine to cells and measuring the incorporation of 34S into protein-bound cellular cysteine and methionine by mass spectrometry. It was found that, as are eucaryotes, both of these archaebacteria were able to convert the sulfur of methionine to cysteine.

Differing activities of medullary respiratory neurons in eupnea and gasping

Our purpose was to compare further eupneic ventilatory activity with that of gasping. Decerebrate, paralyzed, and ventilated cats were used; the vagi were sectioned within the thorax caudal to the laryngeal branches. Activities of the phrenic nerve and medullary respiratory neurons were recorded. Antidromic invasion was used to define bulbospinal, laryngeal, or not antidromically activated units. The ventilatory pattern was reversibly altered to gasping by exposure to 1% carbon monoxide in air. In eupnea, activities of inspiratory neurons commenced at various times during inspiration, and for most the discharge frequency gradually increased. In gasping, the peak discharge frequency of inspiratory neurons was unaltered. However, all commenced activities at the start of the phrenic burst and reached peak discharge almost immediately. The discharge frequencies of all groups of expiratory neurons fell in gasping, with many neurons ceasing activity entirely. These data are consistent with the hypothesis that brain stem mechanisms controlling eupnea and gasping differ fundamentally.

[Research on thixotropic properties of whole blood in patients with ischemic stroke and its high risk]

So far, few papers on alteration of thixotropic properties of blood from patients with cerebrovascular disease have been found. We measured the thixotropic parameters of blood from 92 patients suffering from cerebrovascular diseases. These patients were divided into five groups. Group I consisted of 14 male patients with cerebral arteriosclerosis (CA) (aged 61.7 +/- 8.2 years) and Group II, 12 male patients with transient cerebral ischemic attack (TIA) (64.4 +/- 7.8 years). All of patients in groups III (22 male old patients, 66.6 +/- 5.1 years), IV (24 male middle-aged patients 53.7 +/- 2.8 years), and V (20 female patients 58.4 +/- 13.8 years) were suffering from cerebral thrombosis. These 92 patients and 92 selected healthy subjects were pair matched in sex and age. Using paired t-test, we compared their thixotropic parameters. The results showed that the yield stress (tau 0), the equilibrium value of the structural parameter (A), the apparent viscosity at 2.37 s-1 (eta s), and non-Newtonian contribution of viscosity (eta s-mu) in groups I, II and III were significantly higher than those in the corresponding control groups. The values of tau 0, A, eta s, (eta s-mu) and eta p of blood in group V were higher than those in the control group; only the values of tau 0, eta p, (eta s-mu) of blood in group IV were higher than those in the control group. No significant difference in the thixotropic parameters was noted among groups I, II and III. The results suggest that the patients with cerebrovascular diseases had evidently increased number and degree of RBC aggregation.(ABSTRACT TRUNCATED AT 250 WORDS)

Expression of anionic glutathione S transferase (GST pi) gene in carcinomas of the uterine cervix and in normal cervices

The aim of the present study was to analyse in invasive carcinomas of the uterine cervix, the anionic glutathione S transferase (GST pi) gene, possibly implicated in the drug resistance of human cancers. Total RNA preparations obtained from invasive cervical cancers (106 specimens), carcinomas in situ (CIS) (three specimens) and normal cervical epitheliums (24 specimens) were analysed by Northern and slot blot hybridisation. A 0.7 kb GST pi transcript band was detected in all the cervical specimens. GST pi mRNA levels were lower in normal cervix (mean: 0.7 +/- 0.1 arbitrary units) than in invasive carcinomas (mean: 2.5 +/- 1.5 units) (Student test P less than 10(-4)). However no significant difference was observed between invasive cancers of advanced stages (III and IV) and those of early stages (I and II). The presence of human papillomavirus in cancers and in normal cervices did not influence significantly the GST pi mRNA level. Neither amplification nor gross rearrangement of GST pi gene could be observed after Southern blot analysis of genomic DNA. In conclusion, our data indicate that the presence of high levels of GST pi transcripts in invasive cancers may be a consequence of the multiple biochemical changes which accompany cervical carcinogenesis.

Expression of multidrug-resistance (MDR1) gene in normal epithelia and in invasive carcinomas of the uterine cervix

Total RNA from 92 invasive cervical cancers was analyzed for the presence of multidrug-resistance (MDR1) gene (also known as PGY1) transcripts. A 4.5-kilobase MDR1 transcript band was detected in 40 (43%) of 92 invasive cervical carcinomas and in 15 (68%) of 22 normal cervices. MDR1 levels were low [mean, 2.5 arbitrary units (U)] except in one liver metastasis (50 U) treated with a drug regimen including vincristine. Of eight carcinomas treated by radiotherapy and/or chemotherapy, seven (88%) exhibited MDR1 transcripts as compared with 24 (35%) of 69 untreated carcinomas (Fisher's exact test; P = .01). In conclusion, our data suggest that the MDR1 gene plays a role in drug resistance of certain cervical cancers, but also that other mechanisms may be involved.

Discharge of vagal pulmonary receptors differentially alters neural activities during various stages of expiration in the cat

1. The purpose was to evaluate the hypothesis that neural expiration is composed of two phases: I, a post inspiratory period; and II, the period at which expiratory activities of spinal nerves reach peak values. We hypothesized that the discharge of pulmonary stretch receptors might differentially alter neural activities during these two phases. 2. Activities of the phrenic nerve, intercostal nerve and nerves innervating the thyroarytenoid muscle of the larynx and triangularis sterni muscle of the chest wall were recorded in decerebrate and paralysed cats. 3. The experimental animals were ventilated with a servo-respirator which produced changes in tracheal pressure, and lung volume, in parallel with alterations in integrated activity of the phrenic nerve. 4. In order to assess the influence of the discharge of slowly adapting pulmonary stretch receptors upon neural activities during expiration, lung volume was held at end-expiratory or end-inspiratory levels for individual respiratory cycles. 5. When pulmonary inflation was prevented, phrenic activity increased, as did activity of the thyroarytenoid nerve during early expiration. In contrast, activities of the triangularis sterni and intercostal nerves during mid- to late expiration declined. 6. Holding the lungs at end-inspiratory levels caused a reduction of thyroarytenoid activity and increases in peak triangularis sterni and intercostal activities. Neural expiration typically continued as long as the lungs were maintained at the end-inspiratory level. 7. Responses were qualitatively similar in hypocapnia, normocapnia and hypercapnia, but the magnitude of changes in neural activities was typically augmented with elevations in end-tidal fractional concentrations of CO2. 8. We conclude that the discharge of slowly adapting pulmonary stretch receptors inhibits neural activities during early expiration and augments activities during mid-to late expiration. Hence, our data support the concept that neural expiration is composed of two stages in which neural activities may be differentially controlled.

[Research on thixotropic parameters of whole blood from Chinese adult subjects]

This study measured the thixotropic parameters of whole blood from 314 healthy subjects (154 women, 160 men) with our modified method by Low Shear-30 Rheometer according to Huang's equation. We suggested the range of normal values of thixotropic parameters from man and woman group. The results demonstrated that no significant differences existed in the plasma viscosity (eta p) and fibrinogen between man and woman group. Man group had significantly higher values than those in woman group in hematocrit (HCT), yield stress (tau 0), Newtonian contribution of viscosity (mu), non-Newtonion contribution of viscosity (eta s-mu), apparent viscosity at 2.37s-1 (eta s), the equilibrium value of the structural parameter (A) and apparent kinetic rate constant of rouleaux breakdown (ARC). The man and woman groups could be separately divided into five subgroups on the basis of age. All parameters were compared with one another and treated statistically. We found that the levels of fibrinogen and eta p had an increasing trend with aging. In the old subgroup (greater than or equal to 60 years) of man and woman, HCT, tau 0, mu, eta s, (eta s-mu) and A had significantly lower values than those in young and middle age subgroups. However, it was very interesting that there were differences of ARC versus age between the man and woman groups, i.e., ARC in the man subgroup 3, 4 had lower values and in the woman subgroup 2, 3, 4 had higher values than their respective older subgroups did.

Biosynthesis of caldariellaquinone in Sulfolobus spp

The biosynthesis of caldariellaquionone (CQ) was studied in species of Sulfolobus by measuring the incorporation of stable isotopically labeled tyrosines into CQ. By feeding a series of tyrosines labeled with deuterium or 13C and then measuring the extent and position at which label was incorporated into CQ by mass spectrometry, it was shown that more than 95% of the label was incorporated into the benzo[b]thiophen-4,7-quinone moiety of CQ. From the labeling experiments, it is concluded that the benzo[b]thiophen-4,7-quinone is derived as an intact unit from all of the carbons of tyrosine except C-1.

Tissue-specific expression of c-Ha-ras in premalignant gastrointestinal mucosae

The molecular mechanisms underlying premalignant gastrointestinal diseases, such as ulcerative colitis and Barrett's esophagus, remain unknown. For this reason, the expression of the protooncogene c-Ha-ras was studied in ulcerative colitis and Barrett's esophagus. Total cellular RNA was extracted from different regions of the gastrointestinal tract in these two diseases. Expression of c-Ha-ras was greater in proximal than in distal colon and undetectable in Barrett's esophagus. These regional differences in expression were not seen with the control gene beta-actin or with the protooncogenes c-myc and p53. In order to evaluate structural factors contributing to expression, amplification and methylation of c-Ha-ras DNA were studied in these tissues by Southern and slot blotting. No amplification of c-Ha-ras or six other protooncogenes was detected. These data suggest tissue-specific regulation of c-Ha-ras expression in the gastrointestinal tract in certain premalignant disease states.

Differing control of neural activities during various portions of expiration in the cat

1. Activities of the phrenic nerve, intercostal nerve and nerves innervating the thyroarytenoid (TA) muscle of the larynx and triangularis sterni (TS) muscle of the chest wall were recorded in decerebrate, vagotomized, paralysed and ventilated cats. 2. Neural inspiration was defined by the phase of phrenic activity. Neural expiration was divided into two phases with phase I corresponding to the duration of TA activity and phase II to TS activity: intercostal nerves discharged across both phases. 3. Phrenic activity was terminated prematurely by electrical stimulation of the superior laryngeal nerve or of the dorsolateral region of the rostral pons. Following stimulation, neural activities during phase I of expiration rose and those during phase II fell in most animals. 4. Stimulation of the superior laryngeal nerve during phase I caused augmentations of both TA and TS activity. At the termination of stimulation, a phase of TA discharge was recorded followed by a phase of TS activity. The durations of these post-stimulation phases of TA and TS activities approximated those of cycles without stimulation. 5. Stimulation of the superior laryngeal nerve during phase II caused a resetting of neural expiration. Following stimulation, phases of TA and TS activity were recorded which had durations approximating those of cycles without stimulation. 6. The current required to induce a premature onset of phrenic activity by stimulation of the dorsolateral region of the rostral pons fell dramatically with the change from phase I to phase II of expiration. 7. We conclude that the control of neural activities differs markedly between phase I and phase II of expiration. The data support the hypothesis that post-inspiratory medullary respiratory neurones play a fundamental role in the definition of the ventilatory cycle.

Characterization of expiratory intercostal activity to triangularis sterni in cats

Our purpose was to characterize activity of the intercostal nerve branch innervating the triangularis sterni muscle and the motoneuronal activities comprising this nerve discharge. In decerebrate, vagotomized, paralyzed, and ventilated cats, phasic triangularis sterni neural activity was evident in normocapnia. In most cats, activity did not commence until midexpiration. Activity then rose progressively to terminate at end expiration. Peak neural activities increased in parallel with phrenic activity in hypercapnia and fell in hypocapnia. The progressive increase in triangularis sterni neural activity within each respiratory cycle resulted from recruitment of motoneuronal activities throughout expiration. Once recruited, many motoneurons had a decrementing or constant discharge frequency. In hypercapnia, motoneuronal discharge frequencies increased, and additional activities were recruited. The number of active motoneurons and their discharge frequencies fell in hypocapnia. A similar pattern of motoneuronal activities and responses to stimuli was observed in cats with intact vagi. Factors are considered that may underlie the recruitment pattern of triangularis sterni motoneuronal activities and the inhibition of these in early expiration.

Direct sequencing analysis of exon 1 of the c-K-ras gene shows a low frequency of mutations in human pancreatic adenocarcinomas

We have applied direct dideoxy sequencing of DNA fragments amplified in vitro by the polymerase chain reaction to the detection of mutations in exon 1 of the c-K-ras gene in human pancreatic adenocarcinomas. Four fresh frozen primary tumors, one metastatic tumor, and twelve formalin-fixed paraffin embedded tumors were analysed. Only three cases showed a possible mutation in codon 12 in a small population of cells, in contrast to the high frequency reported for this alteration with the RNAase A protection assay and allele-specific oligoxynucleotide hybridization. No major difference in sensitivity was found between DNA sequence analysis, and the latter method. Our results suggest that if c-K-ras mutations are indeed present in pancreatic adenocarcinomas at the high frequency reported by others, they must be confined to a small fraction of the cell population to escape detection by direct sequencing. Such a phenomenon would have implications for c-K-ras mutations in the pathogenesis of pancreatic adenocarcinomas.

Respiratory activities of intralaryngeal branches of the recurrent laryngeal nerve

To distinguish experimentally between motor nerve activity destined for vocal cord abductor muscles and that bound for muscles that adduct the cords, we recorded efferent activities of intralaryngeal branches of the recurrent laryngeal nerve (RLN) in decerebrate, vagotomized, paralyzed, ventilated cats. Activities of the whole RLN and phrenic nerve were also recorded. Nerve activities were assessed at several steady-state end-tidal O2 and CO2 concentrations. The nerve to the thyroarytenoid (TA) muscle, a vocal cord adductor, was only slightly active under base-line (normocapnic, hyperoxic) conditions but in most cats developed strong activity during expiration in hypocapnia or hypoxia. In severe hypocapnia, phasic expiratory TA activity persisted even during phrenic apnea, indicating continuing activity of the respiratory rhythm generator. The nerve to the posterior cricoarytenoid (PCA) muscle, the vocal cord abductor, was always active in inspiration but often showed expiratory activity as well. This expiratory activity was usually enhanced by hypercapnia and often inhibited by hypoxia. The results are consistent with previous electromyographic findings and emphasize the importance of distinguishing abductor from adductor activity in studies of laryngeal control.

Influence of lung volume on activities of branches of the recurrent laryngeal nerve

To investigate the influence of inspiratory lung inflation on the respiratory activities of laryngeal motor nerves, vagally intact decerebrate paralyzed cats were ventilated by a servorespirator in accordance with their own phrenic nerve activity. Records were made of the activities of the phrenic nerve, the superior laryngeal nerve (SLN), the recurrent laryngeal nerve (RLN), and the intralaryngeal branches of the RLN serving the thyroarytenoid (TA) and posterior cricoarytenoid (PCA) muscles. Neural activities were assessed in the steady state at different end-tidal O2 and CO2 concentrations. Transient responses to withholding inspiratory lung inflation and to preventing expiratory lung emptying were also studied. Hypercapnia and hypoxia increased the inspiratory activities of the phrenic nerve, SLN, RLN, and its PCA branch. TA inspiratory activity was not changed. Expiratory activities of RLN, PCA, and TA were all increased in hypoxia. When lung inflation was withheld, neural inspiratory duration and the inspiratory activities of all nerves increased. The subsequent period of neural expiration was marked by an exaggerated burst of activity by the TA branch of the RLN. TA expiratory activity was also sharply increased after inspiratory efforts that were reflexly delayed by the prevention of lung emptying. TA activity in expiration was enhanced after vagotomy and was usually more prominent than when lung inflation was withheld before vagal section. The results demonstrate the importance and complexity of the influence of vagal afferents on laryngeal motor activity.

Activities of pulmonary stretch receptors during ventilatory cycles without lung inflation

When lung inflation is temporarily withheld in paralyzed, ventilated cats with intact vagi, the activities of inspiratory motor nerves are greater during the second cycle without inflation than during the first. This response is not easily attributable to increasing drive from chemoreceptors as it is abolished by vagotomy. We examined the hypothesis that the increasing inspiratory activity is the result of decreasing inhibitory feedback from pulmonary stretch receptors (PSRs). Decerebrate, paralyzed cats were ventilated by a servo-respirator in accordance with their own phrenic nerve activity. Afferent activities from individual PSRs were recorded from a few cut fibers of one vagus nerve; the vagi were otherwise intact. When lung inflation was withheld, phrenic and hypoglossal nerve activities and the durations of inspiration and expiration all increased and were significantly greater during the second cycle without inflation than during the first. The frequency of PSR discharge was also greater during the second cycle and thus did not account for the responses recorded from the motor nerves. We conclude that the latter responses probably reflect neural processes within the brain stem, involving a persistent inhibitory influence from lung inflation, which outlasts the inflation itself.

[Immunologic changes in serum CuZn-containing superoxide dismutase in patients with lung cancer]

Serum immunologic changed CuZn-containing superoxide dismutase (CuZn-SOD) level was determined in 45 patients with lung cancer and the results were compared with those in 22 normal persons and 19 cases with benign pulmonary diseases. The results were as follows: x +/- Sx of CuZn-SOD in the lung cancer group was 16.11 +/- 0.78 ng/ml, that in the benign pulmonary disease group was 9.51 +/- 0.61 ng/ml and that in the normal adults group was 7.22 +/- 0.79 ng/ml. The mean of the activity of serum immunologic changed CuZn-SOD in patients with lung cancer was significantly high than that in the other two groups. (P less than 0.001). If a serum immunologic changed CuZn-SOD level of 11.98 ng/ml and over is considered as Positive, the positive rate will be 80%, 11%, and 4.5% in the three groups respectively. In the light of the above findings, we suggest that determination of the activity of serum immunologic changed CuZn-SOD is helpful in the diagnosis of lung cancer.

Functions of the retrofacial nucleus in chemosensitivity and ventilatory neurogenesis

The hypothesis was evaluated that neurons within the retrofacial nucleus of medulla integrate afferent stimuli from the central chemoreceptors. In decerebrate, vagotomized, paralyzed and ventilated cats, activity of the phrenic nerve was monitored. Peak integrated phrenic activity increased in hypercapnia; the frequency of phrenic bursts typically declined slightly. The retrofacial nucleus was ablated by radio-frequency lesions or neurons within this nucleus were destroyed by microinjections of kainic acid. Results were similar following lesions or injections. Following unilateral ablations, peak phrenic activity was greatly reduced at normocapnia and hypercapnia; the frequency of phrenic bursts typically rose. Both frequency and peak phrenic activity fell further after the contralateral destruction with a cessation of all phasic phrenic discharge being observed in most animals. Injections of kainic acid in regions rostral, caudal or medial to the retrofacial nucleus produced no consistent changes in phrenic activity. We conclude that neuronal activities in the region of the retrofacial nucleus are important both in the integration of stimuli from the central chemoreceptors and in defining the discharge patterns of respiratory neurons.

Expiratory neural activities in gasping

The purpose was to characterize expiratory-related neural activities in eupnea and gasping. In decerebrate and vagotomized cats, activities were recorded from the phrenic nerve, spinal intercostal and abdominal nerves, and recurrent laryngeal nerve and its branches. Neural inspiration was defined by phrenic discharge. The spinal and laryngeal nerves discharged in inspiration, expiration, or during both phases. Gasping was induced by freezing the brain stem at the pontomedullary junction, exposure to asphyxia or anoxia, or ligation of the basilar artery and its branches. In gasping, peak phrenic activity typically increased as did inspiratory-related activities of laryngeal and spinal nerves. Expiratory activities were greatly reduced in gasping, with some activities being completely eliminated. Reductions of expiratory activity were more prominent for spinal than laryngeal nerves. Similar results were obtained in cats having intact vagi that were ventilated with a servo-respirator so that lung inflation paralleled phrenic activity. The concept that gasping differs fundamentally form other ventilatory patterns is discussed.

Association of multiple copies of the c-erbB-2 oncogene with spread of breast cancer

Amplification of c-erbB-2 was at least three times more frequent in breast cancer than in most other types of carcinoma, and was not found in sarcomas or hematological malignancies. Amplification of c-erbB-2 was found in 15 of 86 primary breast cancers and in 3 of 12 secondary breast cancers. Amplification was more common in breast tumors of advanced stage, and in tumors which had metastasized to regional lymph nodes sites. Gene amplification was observed in 21% (4 of 19) of primary tumors which recurred within 3 years of mastectomy and in 6% (2 of 32) of nonrecurrent tumors.

The effects of a stable analogue of PGE1 on the IgG subclass response to particulate bovine tubular basement membrane in the brown-Norway rat

The IgG subclass and the IgM isotype response to immunization with particulate bovine tubular basement membrane (TBM) and adjuvants was studied in Brown-Norway rats receiving daily injections of a stable analogue of PGE1 (M-PGE1). M-PGE1 slightly reduced the average quantity of circulating TBM antibody as well as the average quantity of eluted IgG per gram of renal tissue as compared to controls. However, M-PGE1 did not qualitatively affect the distribution of the IgG subclass or IgM isotype response to TBM. The IgG response, which occurred predominantly in the IgG1 and IgG2a subclasses, increased from Days 8 to 14 after immunization, while the IgM response decreased over the same time period. The percentage of TBM antibody in the IgG2b subclass was markedly decreased as compared to the percentage of IgG2b antibody in total IgG. A substantial heterogeneity in the IgG subclass response was noted among individual rats with IgG1 constituting from 46 to 82% of circulating TBM antibody. Although no correlation between the IgG subclass response and the severity of tubulointerstitial nephritis was noted, heterogeneity in the IgG subclass response to autoantigens may, nevertheless, theoretically play an important role in the pathogenesis of autoimmune inflammatory phenomena.