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A Kiss

Publications and source records attributed to A Kiss.

At least 433 records · Page 24Linked to original sources

Developmental changes in brain angiotensin II receptors in the rat.

AII binding and distribution were measured in rat brain during development by autoradiographic techniques using radioiodinated [Sar1,Ile8]AII. At all ages, from 2 days to 7 weeks, binding was present in the circumventricular organs, and areas related to pituitary hormone secretion and modulation of sympathetic activity. At early stages of development, AII binding was transiently expressed in a number of motor- and sensory-related areas. These findings support a role for AII in the control of water intake and autonomic activity at all stages of development, and suggest that the peptide may be involved in the maturation of neuronal function during development.

Angiotensin II↗

Cloning of the promoters of an Escherichia coli rRNA gene. New experimental system to study the regulation of rRNA transcription.

The promoters of the rrnB gene of Escherichia coli have been cloned on a multicopy, pBR322-derived plasmid by deleting most of the structural part of rrnB and fusing the terminators of the gene immediately to the promoters. Several further deletions were constructed to vary the promoter-terminator distance, destroy or damage selectively any of the promoters or terminators, and vary the distance between the two pairs of P1 P2 and P3 P4 promoters. All these transcription signals were shown to function on the plasmids in vitro and in vivo. The truncated in vivo transcription products initiated at the P1 and P2 promoters of the recombinant plasmids were found to be stable, and the accumulated transcripts could be easily distinguished from the chromosome-coded rRNA. This provides a convenient experimental system to study the regulation of rRNA biosynthesis.

Chromosome Deletion↗

Molecular cloning and expression in Escherichia coli of two modification methylase genes of Bacillus subtilis.

Two modification methylase genes of Bacillus subtilis R were cloned in Escherichia coli by using a selection procedure which is based on the expression of these genes. Both genes code for DNA-methyltransferases which render the DNA of the cloning host E. coli HB101 insensitive to the BspRI (5'-GGCC) endonuclease of Bacillus sphaericus R. One of the cloned genes is part of the restriction-modification (RM) system BsuRI of B. subtilis R with specificity for 5'-GGCC. The other one is associated with the lysogenizing phage SP beta B and produces the methylase M.BsuP beta BI with specificity for 5'-GGCC. The fragment carrying the SP beta B-derived gene also directs the synthesis in E. coli of a third methylase activity (M.BsuP beta BII), which protects the host DNA against HpaII and MspI cleavage within the sequence 5'-CCGG. Indirect evidence suggests that the two SP beta B modification activities are encoded by the same gene. No cross-hybridization was detected either between the M.BsuRI and M.BsuP beta B genes or between these and the modification methylase gene of B. sphaericus R, which codes for the enzyme M.BspRI with 5'-GGCC specificity.

Bacillus subtilis↗

Behavioral effects of prenatal methoxy-ethyl-mercury chloride exposure in rat pups.

A number of neurotoxic drugs, when administered prenatally, induce neurobehavioral impairments and cause delay of the development of central nervous functions, without morphological malformations. Experiments were undertaken to clarify the behavioral teratogenicity of the fungicide methoxy-ethyl-mercury chloride (MEMC). CFY rat dams were treated with different doses of MEMC during 7th-15th days of gestation (2.0, 0.62 and 0.02 mg/kg daily), perorally. Development of gait, motor coordination, behavior patterns in an open field test, swimming, and conditioned avoidance learning were tested at different ages of rat pups. MEMC did not cause any mortality of dams, but there was a mild ataxia at the 2.0 mg/kg treatment. While birthweight, number of offspring, ear-eye opening and gait were normal, unexpectedly high mortality occurred perinatally. After weaning, open field behavior was nearly normal, there was a mild decrease of rearing, grooming and ambulation and an initial preference for the periphery of the open field decreased. Ambulation increased significantly in 90-day-old pups. Motor coordination on a rotorod decreased in 23- and 36-day-old pups, but increased in 90-day-old pups at the 2.0 mg/kg dose. There was no difference among groups in amphetamine sensitivity tested in a swim stress test. During avoidance conditioning, pups treated with the two higher doses performed poorly when compared to controls and the latency of the positive conditioned response was lengthened significantly. Our results show a dose-dependent behavioral teratogenicity of this organomercurial fungicide. The so called no effect level--as far as the neurobehavioral impairments due to prenatal exposure are concerned--is 0.02 mg/kg daily.

Aging↗

Behavioral consequences of prenatal exposure to the organophosphate insecticide sumithion.

Prenatal administration of Sumithion 50 EC, an organophosphate insecticide, to CFY rats at 5, 10 and 15 mg/kg from days 7 to 15 of gestation, resulted in dose related decreases in open field activity and motor coordination in the offspring treated with the two higher doses. Long lasting alterations in the acquisition and extinction of a conditioned escape response, as well as increased social interactions were observed in the adult offspring. The results indicate a no effect level at 5 mg/kg under the experimental conditions in the present study.

Animals↗

Behavioral deficits due to prenatal exposure to cadmium chloride in CFY rat pups.

The postnatal behavioral effects of 0.20, 0.62 and 2.0 mg/kg cadmium chloride administered to pregnant CFY rats on gestational days 7 through 15 were evaluated. Offspring were tested starting on postnatal day 23 on a rotorod for motor coordination, in an open field device for motor activity and emotionality, in a water-filled tube for stress responses, in the acquisition and extinction of an instrumental shock-escape response and in a social interaction situation. All behavioral measures showed significant alterations at the medium and high dose of cadmium exposure. The results suggest that doses of cadmium chloride that produce no overt toxicity in the dam can have long-lasting behavioral alterations in the offspring.

Aggression↗

Upper gastrointestinal endoscopy findings in patients with long-standing bulimia nervosa.

Bulimia nervosa, an eating disorder now recognized with increasing frequency, is receiving growing attention because of purported complications. Recent claims of a high frequency of erosions, ulceration, and bleeding in the esophagus, ascribed to repeated, self-induced vomiting, prompted us to investigate by endoscopy the upper gastrointestinal mucosa in 37 consecutive patients with long-standing bulimia nervosa. The endoscopic appearance of esophageal and gastric mucosa was normal in 23 patients. Signs of mild esophagitis observed in eight patients were not related to the duration or severity of bulimic behavior or to symptoms of gastroesophageal reflux; two of these eight patients had sliding hiatal hernias. The remaining six patients were found to have superficial mucosal erythema in the stomach or duodenum, but none showed actual erosions, ulcers, or bleeding. Our observations suggest that, in contrast to reports by others, mucosal injury consequent to chronic, self-induced vomiting in patients with bulimia nervosa is relatively infrequent and limited.

Adolescent↗

Hepatitis viruses and hepatocarcinogenesis.

Hepatocellular carcinoma (HCC) is among the most frequent malignancies worldwide. Hepatitis viruses, such as the hepatitis B virus (HBV) and hepatitis C virus (HCV) are undoubtedly listed in the etiology of HCC. Studies show that, in the near future, viral hepatitis will carry increasing weight in the etiology of HCC. This review briefly discusses the known carcinogenic effects of HBV and HCV in the light of experimental and human studies. The data show that viral proteins may directly interfere with gene products responsible for cell proliferation and cell growth. Many other signal transduction cascades may be affected as well. Direct integration of HBV viral sequences into the host genome increases the genomic instability. The genomic imbalance allows the development and survival of malignant clones bearing defected genomic information. HBV and HCV infection induces indirect and direct mechanisms through cellular damage, increased regeneration and cell proliferation, therefore enhancing the development of HCC.

Hepatitis B↗

Expression of a bacterial modification methylase gene in yeast.

Methylation of specific cytosines in the DNA is generally believed to play some role in the regulation of gene expression in eukaryotes. However, some eukaryotes, such as Drosophila and yeast (S. Hattman, personal communication) seem not to contain 5-methylcytosine in their DNA. It would be interesting to test, how gene expression in such organisms would respond to the methylation of specific cytosines in the genome. As a first step towards this goal, we have introduced the gene encoding the Bacillus sphaericus R modification methylase, which methylates the internal cytosine within the recognition sequence 5'-GGCC, into yeast cells. Southern-type hybridization to DNAs isolated from the transformed yeast clones revealed that the yeast plasmid carrying the prokaryotic methylase gene, as well as the two chromosomal genes tested (his3 and leu2) were methylated, whereas the bulk of the yeast DNA remained largely unmethylated. This indicates that the Bacillus sphaericus modification methylase was expressed in yeast but it modified only certain parts of the yeast DNA.

Bacillus↗

Improving communication skills--a randomized controlled behaviorally oriented intervention study for residents in internal medicine.

OBJECTIVE: We investigated whether patient-centered communication skills can be taught to residents in Internal Medicine by using a time-limited behaviorally oriented intervention. METHOD: Residents working at the Department of Internal Medicine were randomly assigned to an intervention group (IG; N = 19) or a control group (CG; N = 23). In addition to 6 hours of standard medical education per week, the IG received specific communication training of 22.5 hours duration within a 6-month period. Initially and 10 months later, participants performed interviews with simulated patients. Interviews were rated by blinded raters who used the Maastricht History and Advice Checklist-Revised. RESULTS: Compared with the CG, the IG improved substantially in many specific communication skills. Both groups improved in the "amount of medical information identified" and in the ability to "communicate about feasibility of treatment." CONCLUSION: Patient-centered communication skills such as those presented in this intervention study can be taught. The ability to gain medical information and the readiness to communicate about aspects of medical treatment seem to improve with more professional experience; however, they also profit from the intervention.

Adult↗

Cardiovascular indices of peripheral and central sympathetic activation.

OBJECTIVE: A number of sympathetic nervous system (SNS) parameters have been used in cardiovascular psychophysiology. This study aimed to describe the pattern and redundancy of a set of SNS parameters during peripherally induced changes of cardiac sympathetic activation and reflex modulation of central SNS control. Preejection period (PEP) was assessed as a marker of peripheral sympathetic activation. Low-frequency blood pressure variability (BPV) was assessed as an estimate of central SNS control. METHODS: Peripheral beta-sympathetic stimulation and blockade were achieved with epinephrine and esmolol hydrochloride (beta1-blockade), respectively. Changes in central SNS output were induced by loading and unloading arterial baroreceptors with norepinephrine and nitroprusside sodium, respectively. This single-blinded, crossover study in 24 healthy men also included two placebo control periods. PEP was derived from impedance cardiography and adjusted individually for heart rate. BPV was calculated by power spectral analyses of beat-to-beat heart rate and systolic blood pressure (Finapres system) data. RESULTS: PEP decreased during epinephrine infusion (-40.1 +/- 3.8 ms, p <.0001) and increased during esmolol infusion (+6.6 +/- 3.5 ms, p =.05). PEP was shortened after central SNS activation by nitroprusside (-16.8 +/- 2.9 ms, p < 0.0001). Systolic BPV in the low-frequency range (0.07-0.14 Hz, Mayer waves) increased during nitroprusside infusion (+0.44 +/- 0.19 ln mm Hg(2), p =.03) and decreased during norepinephrine infusion (-0.67 +/- 0.13 ln mm Hg(2), p < 0.0001). Low-frequency BPV did not change significantly during epinephrine or esmolol infusion. CONCLUSIONS: Our data provide empirical evidence of separable peripheral and central sympathetic response components. The combined report of low-frequency BPV and PEP gives distinct information on both central SNS control and the level of sympathetic cardiac activation achieved.

Adrenergic alpha-Agonists↗

Multicentric Castleman disease and systemic lupus erythematosus phenotype in a boy with Klinefelter syndrome: long-term disease stabilization with interferon therapy.

An 11-year-old boy with Klinefelter syndrome had Castleman disease (CD) of plasma cell type develop. Nonregulated antibody production mimicked systemic lupus erythematosus (SLE). Hepatitis C virus (HCV) infection caused significant disease worsening. The patient was treated with a daily dosage of 2 million units/m2 of IFN-alpha. Dramatic clinical improvement and decreasing autoimmune phenomenon were observed. HCV RNA were cleared. Hypergammaglobulinemia did not change. The boy has been living for 8 years with his disease. Plasma cell type CD can mimic collagenosis. Disease worsening is caused by HCV, though it can be reversed with IFN-alpha. Klinefelter syndrome may be a genetic susceptibility factor for CD in some cases.

Castleman Disease↗

Mutational analysis of the function of Met137 and Ile197, two amino acids implicated in sequence-specific DNA recognition by the EcoRI endonuclease.

The gene encoding the EcoRI endonuclease was altered by site-directed mutagenesis to introduce multiple substitutions of M137 and 1197, two amino acids which were suggested by the revised crystal structure to mediate recognition of the cytosines in the 5'-GAATTC-3' target sequence. Eight substitutions of M137 and ten substitutions of 1197 were isolated. With the exception of M137W, M137P and M137K, all mutant enzymes retained enough activity to damage cellular DNA in the absence of the EcoRI methyltransferase. All M137 replacements abolished the ability of the enzyme to restrict phage growth. Conservative replacements at 1197 (L, V) did not impair phage restriction, whereas non-conservative changes reduced (G, W) or abolished (D, P) restriction. In general, substitutions at M137 were more deleterious than substitutions at I197. Double mutants with combinations of M137G/A and I197G/A mutations exhibited a phenotype characteristic for the respective single M137 mutant. Double mutants carrying combinations of the M137G/A replacements and substitutions at R200 were viable even in the absence of the methyltransferase, suggesting that disrupting contacts to both bases of the GC base pair inactivates the enzyme. None of the replacements resulted in relaxed recognition specificity. In summary, our findings are consistent with a role for M137 but do not support such a role for I197 in substrate recognition by the EcoRI endonuclease.

Bacteriophage lambda↗

Insulin production rate in normal man as an estimate for calibration of continuous intravenous insulin infusion in insulin-dependent diabetic patients.

This study examines the feasibility of deriving the 24-h insulin requirement of insulin-dependent diabetic patients who were devoid of any endogenous insulin release (IDD) from the insulin-production rate (IPR) of healthy man (basal, 17 mU/min; stimulated 1.35 U/12.5 g glucose). To this end, continuous intravenous insulin infusion (CIVII) was initiated at a precalculated rate of 41.2 +/- 4.6 (SD) U/24 h in IDD (N - 12). Blood glucose profiles were compared with those obtained during intermittent subcutaneous (s.c.) insulin therapy (IIT) and those of healthy controls (N = 7). Regular insulin (Hoechst CS) was infused with an adapted Mill Hill Infuser at a basal infusion rate of 1.6 U/h (6:00 a.m. to 8:00 p.m.), and of 0.8 U/h from 8:00 p.m. to 6:00 a.m. Preprandial insulin (3.2-6.4 U) was added for breakfast, lunch, and dinner. Daily individual food intake totaled 7688 +/- 784 kJ (1836 +/- 187 kcal)/24 h including 184 +/- 37 g of glucose. Proper control of blood glucose (BG) (mean BG 105 +/- 10 mg/dl; mean amplitude of glycemic excursions 54 +/- 18 mg/dl; and 1 h postprandial BG levels not exceeding 160 mg/dl) and of plasma concentrations of beta-hydroxybutyrate and lactate was maintained by 41.4 +/- 4.4 U insulin/24 h. Although BG values only approximated the upper normal range as seen in healthy controls, they were well within the range reported by others during CIVII. Therefore, we conclude that in adult IDD completely devoid of endogenous insulin (1) the IPR of normal man can be used during CIVII as an estimate for the patient's minimal insulin requirement per 24 h, and (2) this approach allows for a blood glucose profile close to the upper range of a normal control group. Thus, deriving a patient's daily insulin dose from the insulin production rate of healthy man may add an additional experimental protocol which aids in making general calculations of a necessary insulin dose instead of using trial and error or a closed-loop insulin infusion system.

3-Hydroxybutyric Acid↗

[7-aza analogs of quinazolino-carboline alkaloids. Synthesis, structure, characterization].

The synthesis, structure and characterization of 8-substituted-7-azarutaecarpines (2) is described. These compounds were prepared by Fischer indolization of 3-amino-2-(1-phenylhydrazonoethyl)-4(3H)-quinazolin-one (5), followed by cyclocondensation with a series of aliphatic or aromatic aldehydes and formic acid or a Vilsmeyer-Haack reagent. The stereochemistry of compounds (2) was investigated by 1H nmr spectroscopy. It was found that the 8-substituents assume a quasi-axial position on the flattened boat conformation of ring C of (2), with the exception of ortho substituted phenyl groups, which occupy quasi-equatorial position. Semiempirical MO calculations support these conformational preferences.

Alkaloids↗