Trazodone treatment increases plasma prolactin concentrations in depressed patients

m-Chlorophenylpiperazine (m-CPP), which is a metabolite of trazodone, is a serotonin agonist. To examine for the possibility that m-CPP is involved in biochemical effects during treatment with the parent compound, prolactin response to trazodone treatment (150 mg at bedtime for 3 weeks) was studied in 12 depressed patients. The means +/- S.D. of plasma prolactin concentrations before treatment, 12 h, and 1, 2 and 3 weeks after initiation of treatment were 9.1 +/- 5.6, 14.7 +/- 9.1, 15.3 +/- 8.5, 13.2 +/- 7.0 and 13.0 +/- 7.0 ng/ml, respectively. The mean prolactin concentrations at 12 h (p < 0.01), 1 week (p < 0.001) and 2 weeks (p < 0.05) were significantly higher than that before treatment. The present study thus shows that trazodone treatment increases prolactin concentrations, suggesting that m-CPP is involved in biochemical effects during treatment with the parent compound.

Two kinds of neutral serine proteinases in salted muscle of anchovy, Engraulis japonica

Two kinds of proteinases, type-I and type-II, were purified or partially purified from salted muscle of anchovy, Engraulis japonica. Mol. wts. of type-I and type-II proteinases were estimated to 25,000 and 37,000, respectively, on electrophoretic analysis. Both proteinases strongly hydrolyzed synthetic tri or tetrapeptide substrates specific to trypsin, alpha-thrombin, and an activated protein C, while they hardly hydrolyzed Arg-MCA and benzoyl Arg-MCA derivatives. The proteinases were inhibited by common trypsin inhibitors. Optimal pH for the proteinase activities were pH 6.8 (type-I) and pH 7.0 to 7.5 (type-II), and the proteinases showed the highest activities at 45 degrees C (type-I) and 50 degrees C (type-II). The N-terminal amino acid sequence of type-I proteinase, 1I-2V-3G-4G ... (29 residues were identified), was significantly similar to sequences of trypsins and tryptases. Based on these findings, both proteinases were presumed to be kinds of tryptases in E. japonica muscle.

Frequent loss of heterozygosity at the deleted in colorectal carcinoma gene locus and its association with histologic phenotypes in breast carcinoma

Loss of heterozygosity (LOH) at the deleted in colorectal carcinoma gene (DCC), a tumour suppressor gene that encodes a protein with high homology to the neural cell adhesion molecule, was investigated in 42 surgical specimens of primary breast carcinoma. LOH was analysed in breast carcinoma by amplifying the DNA, spanning a variable number of tandem repeats site and a restriction fragment length polymorphism site within DCC, using the polymerase chain reaction (PCR). Cell sorting was used to enrich carcinoma cells. The expression of the DCC gene was also investigated using a reverse transcription-PCR method followed by Southern blot hybridization. LOH at the DCC locus was detected in 15 (51.7%) of 29 informative cases and 10 of 13 cases having DCC-LOH showed distinct reduction or loss of DCC expression. The DCC-LOH was closely associated with certain histological phenotypes: DCC-LOH was more frequent in scirrhous carcinomas than in solid-tubular ones (P < 0.05), and was also more frequent in carcinomas with infiltration into fat tissue over the mammary gland than in those without infiltration (P < 0.05). DCC-LOH was detected in invasive lobular carcinomas (2/2), but in none of the noninvasive ductal carcinomas (0/2). These observations suggest that malignant histological phenotypes are associated with DCC-LOH.

Antigenic and genetic characteristics of H1N1 human influenza virus isolated from pigs in Japan

Two strains of influenza A virus were isolated from pigs in northern Japan in 1992. Serological tests showed that the haemagglutinin (HA) and neuraminidase (NA) antigens were more closely related to those of recent human H1N1 viruses than to those of swine H1N1 viruses. The HA and NA genes of isolate A/sw/Obihiro/5/92 were shown to be closely related to those of current human H1N1 viruses. Evolutionary trees constructed from nucleotide sequences showed that the HA and NA genes of A/sw/Obihiro/5/92 were apparently on a branch cluster containing human strains isolated between 1990 and 1992.

High-performance liquid chromatographic determination of trazodone and 1-m-chlorophenylpiperazine with ultraviolet and electrochemical detector

A high-performance liquid chromatographic (HPLC) assay was developed for the determination of trazodone and its metabolite, 1-m-chlorophenylpiperazine (m-CPP), in plasma. The high level of trazodone in plasma was detected by ultraviolet absorbance at 254 nm and the low level of m-CPP in plasma was detected by coulometric electrochemical detection at 840 mV on the series arrangement of two detectors. Pilsicainide as an internal standard for both compounds was monitored by both detectors. Trazodone and m-CPP in plasma were extracted by a rapid and simple procedure based on CN bonded-phase extraction, and C8 reversed-phase HPLC separation. Determination was possible for trazodone in the concentration range 100-2000 ng mL-1 and for m-CPP in the concentration range 5-100 ng mL-1. The recoveries of trazodone and m-CPP added to plasma were 81.0-84.2 and 68.0-73.2%, respectively, with coefficients of variation of less than 7.3 and 8.2%, respectively. The method is applicable to high level monitoring of trazodone and low level monitoring of m-CPP in plasma of healthy volunteers and patients treated with trazodone.

Rapid bulk replacement of acceptor membrane by donor membrane during phagosome to phagoacidosome transformation in Paramecium

The extent to which a donor membrane will be retrieved, or if it is retrieved at all after it fuses with an acceptor membrane, is usually difficult to determine. We have studied the dynamics of membrane retrieval in the phagosome system of Paramecium multimicronucleatum using six monoclonal antibody markers. Our previous freeze-fracture and transmission electron microscopic studies have indicated that extensive changes take place in the membrane of the young phagosome as it progresses through its cycle. Using immunofluorescence and immunoelectron microscopy to determine the times of entry and exit of these individual antigens into the digestive vacuole system, we showed that two hydrophilic antigens, one located on the cytosolic and one on the lumenal side of the discoidal membrane (phagosome membrane precursor), were completely retrieved from the phagosome by tubulation within the first three minutes. At the same time that this membrane was retrieved, membrane from a second population of vesicles, the acidosomes, fused with the phagosome to produce the phagoacidosome. On the basis of immunogold localization on cryosections of a total of six antigens, the two specific for phagosome/discoidal vesicle membrane as well as four specific for the acidosome/phagoacidosome membrane, this replacement is total. We also showed that in the presence of the actin-active drug cytochalasin B, this replacement was essentially prevented. However, when vacuole acidification was neutralized by ammonium chloride, this replacement process continued unaffected after a lag. Consequently, acidification, per se, is not required to trigger the replacement of the phagosome membrane. We conclude, on the basis of these studies as well as our previous freeze-fracture studies that during phagoacidosome formation most of the acceptor membrane is retrieved and is replaced by the donor membrane. This shows that at least one cell type possesses the mechanisms needed to substantially replace the membrane of a phagosomal compartment when radical and rapid changes are needed to modulate the digestive and absorptive processes.

[Corneal autofluorescence in patients with diabetic retinopathy]

Corneal autofluorescence was investigated by fluorophotometry in patients with non-insulin-dependent diabetes mellitus and healthy volunteers, and evaluated as to its correlation with diabetic retinopathy. The corneal autofluorescence of diabetes patients, which was significantly higher than that of healthy controls, correlated significantly with the severity of retinopathy. In addition, the corneal autofluorescence of burned-out retinopathy patients was significantly lower than that of proliferative retinopathy patients. These results suggest that corneal autofluorescence is correlated with retinal ischemia and that corneal autofluorescence can be an indicator of the activity of diabetic retinopathy. Corneal autofluorescence may originate in the accumulation of some factor induced by retinal ischemia within the corneal stroma.

Genetic analysis of porcine H3N2 viruses originating in southern China

From immunological and phylogenetic analyses of H3 influenza viruses isolated from pigs and ducks in the People's Republic of China (China), Hong Kong, Taiwan and Japan, between 1968 and 1982, we arrived at the following conclusions. The H3 haemagglutinin and N2 neuraminidase genes from swine isolates can be segregated into four mammalian lineages, including: (i) the earliest human strains; (ii) early swine strains including Hong Kong isolates from 1976-1977; (iii) an intermediate strain between the early swine and recent human strains; and (iv) recent human strains. In this study we found an unusual swine strain (sw/Hong Kong/127/82) belonging to the third lineage which behaved like those of the early swine-like lineage in the haemagglutination inhibition test; but neuraminidase inhibition profiles with monoclonal antibodies indicated that this virus is related to late human strains. On the basis of pairwise comparisons of complete or partial nucleotide sequences the genes encoding the three polymerase proteins (PB2, PB1, PA), the nucleoprotein, the membrane protein and possibly the nonstructural proteins of sw/Hong Kong/127/82 are of the swine H1N1 lineage, whereas genes encoding the two surface glycoproteins belong to the human H3N2 lineage. In contrast, all RNA segments of one swine isolate (sw/Hong Kong/81/78) are similar to those of recent human H3N2 viruses. This study indicated that frequent interspecies infections between human and swine hosts appeared to occur during 1976-82. Although the evolutionary rates of human (0.0122/site/year), swine (0.0127/site/year) and avian (0.0193/site/year) virus genes are similar when based upon synonymous substitutions, nonsynonymous substitutions indicated that viral genes derived from human and swine viruses evolved about three times faster (0.0026-0.0027/site/year) than those of avian viruses (0.0008/site/year). Furthermore, the evolutionary mechanism by which human and swine H3 haemagglutinin genes evolve at a similar rate, based on nonsynonymous substitutions, appeared to be quite different from previous evidence which showed that human H1 haemagglutinin genes evolved three times faster than those of swine viruses. However, comparison of the number of nonsynonymous substitutions in the antigenic sites (A-E) of haemagglutinin molecules demonstrated that swine viruses evolve at a rate that is about one fifth to one tenth that of human viruses, reflecting the conservative nature of the antigenic structure in the former.

Intraplatelet free calcium concentrations and alcohol-related blood pressure elevation in a middle-aged male population

Elevated intracellular free calcium (Ca2+) has been proposed as a mechanism of alcohol-induced hypertension from animal experimental studies, but this has not been confirmed in man. In the present study, intraplatelet Ca2+ concentration (plt.[Ca2+]i) was measured in 83 middle-aged men, and the associations between alcohol consumption, age, body mass index (BMI), hematological and serum biochemical variables, plt.[Ca2+]i and blood pressure were analyzed. Plt.[Ca2+]i did not show a significant univariate correlation with alcohol consumption or with blood pressure, but did so with serum gamma-glutamyl transpeptidase (gamma-GTP) levels. Age, BMI and serum gamma-GTP were selected as independent contributors to blood pressure, and gamma-GTP alone was selected as the determinant of plt.[Ca2+]i by multiple regression analyses. The association between gamma-GTP and plt.[Ca2+]i was shown to be common or at least very similar in both drinkers and nondrinkers by generalized linear model analysis. Therefore, chronic alcohol consumption in humans may relate to elevations of plt.[Ca2+]i, not mainly by the direct action of alcohol but by some metabolic alterations after alcohol consumption. The significance of elevated plt.[Ca2+]i in drinkers in the development of hypertension, however, remains obscure.

[Characterization of peripheral blood natural killer (NK) cells in two patients with CD16+ CD56- NK cell-lineage granular lymphocyte-proliferative disorder]

In normal peripheral blood natural killer (NK) cells, the subset of CD16+ CD56+ cells is predominant, and that of CD16+ CD56- cells is rarely present. Because we have found the expansion of CD16+ CD56- NK cells in the peripheral blood of two patients with NK cell-lineage granular lymphocyte-proliferative disorders (NK-GLPD), the clinical findings and cellular characteristics of these patients were compared with those of CD16+ CD56+ NK-GLPD patients. Although CD16+ CD56- and CD16+ CD56+ NK-GLPD cells were morphologically different, clinical findings and courses, and NK activity did not differ significantly. Because strong NK activity was demonstrated in CD16+ CD56- NK-GLPD cells, the CD56 antigen, one of the adhesion molecules, did not seem to play a major role in NK cell-mediated cytotoxicity. The CD56 antigen is known to be more strongly expressed by immature NK cells than by mature NK cells. However, because interleukin 2-activated CD16+ CD56- NK-GLPD cells rapidly expressed the CD56 antigen, the degree of CD56 antigen expression did not always correlate with the maturity of NK cells.

[Progressive pulmonary fibrosis in a case of Sjögren's syndrome with asbestos exposure]

A 62-year-old man had an occupational history of exposure to asbestos for 27 years (1947-1974). Dry mouth, dry eyes and swollen gums were noted in 1974. Sjögren's syndrome was diagnosed in 1975. The chest radiograph in 1984 showed bilateral pleural thickening and small reticular opacities in the left lower lung field. In 1990, he complained of dyspnea and cough, and diffuse interstitial pneumonia was diagnosed. While being treated for diffuse interstitial pneumonia, pulmonary fibrosis progressed rapidly, and advanced pulmonary fibrosis was obvious in 1992. Laboratory data showed hyper gamma-globulinemia (36.8%) and a high level of IgG (3772 mg/dl) in 1976. These values decreased to within the normal ranges during the subsequent clinical course. The results of lymphocyte subset counts in 1988 were normal. With the progression of diffuse interstitial pneumonia in 1990, the lymphocyte subset counts showed a low percentage of CD4 (19.2%), a low CD4/8 ratio (0.46), and a low percentage of CD20 (26.8%). In 1992, as pulmonary fibrosis progressed despite treatment, the disorder of lymphocyte subsets became worse. The CD4 percentage was very low (5.0%), as was the CD4/8 ratio (0.08), and the percentage of CD20 (1.4%); the CD8 percentage was high (64.7%), as was the percentage of Leu 7 (49.0%). These immunologic and pulmonary changes could be not explained by Sjögren's syndrome. Determining what factor induced these changes is difficult, but asbestos exposure is a likely cause.

Association between hepatic steatosis, insulin resistance and hyperinsulinaemia as related to hypertension in alcohol consumers and obese people

The presence of hepatic steatosis was determined in 180 middle-aged male workers by ultrasonography and was found in 39 (22%) of them. Body mass index (BMI), systolic and diastolic blood pressure (BP) and serum levels of asparate aminotransferase (AST), alanine aminotransferase (ALT) and gamma-glutamyl transpeptidase (gamma-GTP) were higher in the subjects with hepatic steatosis. Although the volume of alcohol consumed in a week did not differ between the subjects with and without hepatic steatosis, the hepatic steatosis was thought to relate to both increased body mass and alcohol consumption because the elevations of serum AST and gamma-GTP in the subjects depended largely on alcohol consumption but not on BMI. The results of 75 g oral glucose tolerance test showed a higher blood glucose at 120 minutes and a higher plasma immunoreactive insulin at baseline, 60 and 120 minutes in the subjects with hepatic steatosis, being adjusted for age, BMI and alcohol consumption. The significant association between serum gamma-GTP and BP, which had been often observed in alcohol consumers, was no longer significant after adjustment for plasma insulin levels whereas plasma insulin showed a significant association with BP. These results suggest the possibility that hypertension in alcohol consumers, and also in obese people, relates at least partly to hyperinsulinaemia associated with progression in hepatic steatosis.

Aberrations of the APC gene in primary breast carcinoma

Aberrations of the APC gene, which plays an important role in the genesis of familial adenomatous polyposis and colorectal carcinoma, were investigated in 31 surgical specimens of primary breast carcinoma. These studies utilized the polymerase chain reaction followed by restriction-fragment-length polymorphism and single-strand-conformation polymorphism analyses combined with tumor cell enrichment by cell sorting. Loss of heterozygosity at the APC locus was detected in 8 (38%) of 21 informative cases, but only 2 (6%) of 31 tumors carried a mutated APC gene. Direct DNA sequencing analysis confirmed mutations at codon 1081 (AGC to ATC) resulting in an amino acid substitution of serine for isoleucine, and at codon 1096 (CAG to CAT) resulting in a substitution of glutamine for histidine. There were no significant correlations between the loss of heterozygosity or mutation at the APC locus and any clinicopathological characteristics. Our present observations suggest that the mutations of the APC gene may play an important role in the genesis of certain breast carcinomas, and that another tumor-suppressor gene, which is the true target of frequent loss of heterozygosity, may exist near the APC gene.

Effects of age and sex on sodium chloride sensitivity: association with plasma renin activity

The mechanism by which excessive NaCl intake raises blood pressure has not been fully clarified. The present study was undertaken in 87 Japanese inpatients with essential hypertension to investigate the interrelation among effects of age, sex and the renin-angiotensin system on NaCl sensitivity. After ingesting a regular NaCl diet (170 mmol/day) for one week, subjects were placed sequentially on a week of low NaCl diet (50 mmol/day) and a week of high NaCl diet (340 mmol/day). NaCl sensitivity defined as the difference in mean blood pressure between the low and high NaCl diets did not differ between genders. NaCl sensitivity was positively correlated with age and the change in PRA. The fall in PRA after NaCl loading was significantly smaller in women than in men. By multiple regression analysis, age and the change in PRA independently contributed to the change in mean blood pressure. Furthermore, the interaction between sex and the change in PRA was selected as a statistically significant variable. In conclusion, NaCl sensitivity of blood pressure is independently associated with age and the inadequate suppression of the renin-angiotensin system. Because the contribution of the change in PRA to NaCl sensitivity was greater in women than in men, the mechanism of blood pressure elevation after NaCl loading may differ between genders.

Lack of increase in platelet Ca2+ and Na+ in deoxycorticosterone acetate-salt hypertensive rats

We have previously characterized abnormal Ca2+ handling in platelets of spontaneously hypertensive rats (SHRs). In this study, we investigated whether cellular Ca2+ metabolism and/or Na+ concentration is altered in platelets of deoxycorticosterone acetate-salt hypertensive rats (DOCA rats). The resting cytosolic Ca2+ concentration ([Ca2+]i) in platelets was significantly lower in DOCA rats than controls (54.5 +/- 1.4 vs. 61.2 +/- 2.3 nmol/l). The amplitude of the [Ca2+]i transient induced by thrombin was significantly increased in the absence, but not the presence, of external Ca2+ in DOCA rats compared with control rats. The [Ca2+]i response to 5 mumol/l ionomycin in the Ca(2+)-free buffer was greater in DOCA rats than in controls (546 +/- 23 vs. 470 +/- 18 nmol/l), indicating larger intracellular Ca2+ stores. The rate of recovery of [Ca2+]i after the peak response to thrombin was decreased in DOCA rats (79% at 0.1 U/ml and 91% at 1.0 U/ml thrombin of control rats). Cytosolic Na+ concentration ([Na+]i) in platelets was similar in DOCA and control rats. Altered Ca2+ levels are not correlated with [Na+]i in this salt-sensitive hypertensive model. Therefore, an increased [Ca2+]i is not an obligatory phenomenon in hypertension.

Erythrocyte Na+/K(+)-ATPase and membrane and serum lipid profiles: as related to alcohol, body mass index and blood pressure

Erythrocyte Na+/K(+)-pump activities have been measured in hypertensives, alcohol consumers and obese persons, but the results have been variously reported as decreased, increased or unchanged. We analyzed the relationships between erythrocyte Na+/K(+)-ATPase activities and the membrane and serum lipid profiles in 83 middle-aged men, to clarify the reasons for these inconsistencies. Increases in erythrocyte Na+/K(+)-ATPase activity related closely to decreases in cholesterol to phospholipid (C/P) ratio of the erythrocyte membrane. Decreases in the C/P ratio in turn related closely to elevations of serum triglycerides (TG) with increasing body mass index, and weakly to the volume of alcohol consumed. Thus, erythrocyte Na+/K(+)-ATPase activities depend largely on the membrane and serum lipid profiles as related to body weight and alcohol consumption, and which may be a cause of the previous conflicting findings. Erythrocyte Na+/K(+)-ATPase showed a positive association with blood pressure, independently of age, body mass index and serum gamma-glutamyl transpeptidase levels. Although the biological link of elevated erythrocyte Na+/K(+)-ATPase with the rise in blood pressure remains unclear, it may be a reflection of hyperinsulinemia in the subjects with a higher blood pressure due to overweight or excessive alcohol consumption.

Efficacy of inactivated vaccine in preventing antigenically drifted influenza type A and well-matched type B

OBJECTIVE

To evaluate the efficacy of currently used inactivated influenza vaccine during a severe epidemic caused by antigenically drifted influenza type A(H3N2) and well-matched type B viruses during the 1992-1993 season.

DESIGN

Prospective nonrandomized controlled trial.

SETTING

An urban general hospital pediatric asthma clinic in Japan.

PARTICIPANTS

A total of 137 children with moderate to severe asthma (mean age, 7.0 years; range, 2 to 14 years).

INTERVENTION

Eighty-five children received trivalent split-antigen vaccine containing A/Beijing/352/89 (H3N2) and B/Bangkok/163/90 (B/Panama/45/90-like strain). Fifty-two were unvaccinated.

MAIN OUTCOME MEASURES

Protection against infection was determined using hemagglutination inhibition test and virus isolation. Clinical efficacy was estimated based on febrile episodes with antibody rise or virus isolation.

RESULTS

Although marked antigenic drift in hemagglutinin was demonstrated in the epidemic virus (A/Beijing/32/92-like strain), the protection against influenza type A(H3N2) infection was 67.5% (P < .01). The protection against influenza type B infection was 43.7% (P < .01), although the epidemic influenza type B viruses were antigenically almost identical to the vaccine strain. Inactivated vaccine was not effective for protection against influenza type B infection in children younger than 7 years. High clinical effectiveness was demonstrated in children at least 7 years of age during the epidemic.

CONCLUSIONS

Our data suggest that current inactivated vaccine is highly effective for protection against influenza type A(H3N2) virus infection regardless of antigenic drift. In contrast, the protective efficacy obtained by vaccination may not be sufficient against influenza type B virus infection, and especially in young children, it does not offer protection.

A novel antagonist, phenylbenzene omega-phosphono-alpha-amino acid, for strychnine-sensitive glycine receptors in the rat spinal cord

1. 3-[2'-Phosphonomethyl[1,1'-biphenyl]-3-yl]alanine (PMBA) is a novel glycine antagonist at strychnine-sensitive receptors. The chemical structure of PMBA, possessing both a glycine moiety and a phosphono group, is quite different from that of strychnine. 2. In the spinal motoneurone of newborn rats, glycine (100 microM-1 mM) induced depolarizing responses in a concentration-dependent manner. PMBA effectively inhibited depolarizing responses to glycine and other agonists, such as taurine and beta-alanine. The dose-response curves for glycine were shifted to the right in an almost parallel manner (pA2 value: 5.30 +/- 0.23, n = 5) by PMBA which was about 60 times less potent than strychnine (pA2 value: 7.08 +/- 0.21, n = 5) as a glycine antagonist. 3. PMBA (1-100 microM) did not interact with modulatory glycine sites on N-methyl-D-aspartate (NMDA) receptors, which suggests a high selectivity of PMBA for strychnine-sensitive glycine receptors. At considerably high concentrations (0.1 mM-1 mM), PMBA depressed responses to GABA (pA2 value: 3.57 +/- 0.24, n = 3). 4. PMBA inhibited the binding of [3H]-strychnine to synaptosomes from adult rat spinal cords; the IC50 values of PMBA, glycine and strychnine were 8 +/- 2, 9 +/- 3 and 0.08 +/- 0.04 microM, respectively (n = 5) for [3H]-strychnine (4.8 nM). 5. PMBA is a central excitant drug with relatively high potency and selectivity and should be useful as a pharmacological probe for analysing the mechanisms underlying physiological functions of glycine receptors.