Organization of repeated sequences in the region downstream to rRNA genes in the rDNA episome of Entamoeba histolytica.

The E. histolytica rDNA episome consists of a 3.7 kb HindIII fragment located downstream of the rDNA inverted repeats. We have determined the complete nucleotide sequence of this fragment and have shown that it is comprised of two families of short tandem repeats, the 170 bp DraI repeat and the 144 bp ScaI repeat. Each DraI repeat unit consists of 12-mer sequences with near complete homology to yeast consensus autonomously replicating sequence. In addition, a 21-mer subrepeat structure is also present in each unit. The sequence of the ScaI repeat is about 90% homologous with the sequence of another family of 145 bp tandem repeats, the PvuI repeats reported to be present upstream of the rRNA genes (3). Compared with most other parts of the rDNA episome, the downstream region showed frequent restriction fragment length polymorphism. This was due to changes in the number of tandem DraI repeat units. The loss of these repeats might explain how rDNA length heterogeneity observed in the clones of HM1:IMSS could have arisen. On the other hand, the number of ScaI repeat units in these clones remained unchanged. The repeat units found in the 3.7 kb HindIII fragment show superficial resemblance to equivalent regions of the intergenic spacers of higher eukaryotes. Moreover, these repeated sequences seem to be specific for the pathogenic strain of E. histolytica.


P-glycoprotein genes of Entamoeba histolytica.

Six different P-glycoprotein gene segments were identified from an emetine-resistant E. histolytica mutant, which overexpresses mRNAs homologous to segments of the human mdr1 (P-glycoprotein) gene. The open reading frames of two completely sequenced genes EhPgp1 and EhPgp2 were 1,302 and 1,310 amino acids long, respectively, and showed a 67% positional identity with each other and 41 and 40% positional identities, respectively, with human mdr1 gene. Within each ameba P-glycoprotein were the ATP-binding sites found twice in eukaryotic P-glycoproteins and once in prokaryotic transport proteins. A phylogenetic tree showed that Entamoeba P-glycoproteins are more related to the human and mouse P-glycoproteins than to the Plasmodium and Leishmania P-glycoproteins. In addition, there were two P-glycoprotein pseudogenes, each with a frame shift and stop codons in identical places within the amino ATP-binding site.


Ciguatoxic fish in the French West Indies.

An epidemiological study on ciguatera fish poisoning in the French West Indies on St-Barthelemy, St-Martin and Anguilla was conducted in the years 1985-1986-1987 and 1991-1992. A study on the toxicity of coral fish was realized. The toxicity of 700 fish belonging to 57 species was evaluated by bio-assays. 430 mosquito-bio-assays were performed on individual fish (flesh or liver) and 19 on pools (flesh or liver; with 4 to 24 fish). A second group was evaluated on liver by the chick feeding-test (33 individual and 64 on pools with 2 to 24 fish). The results showed that many species are involved in the toxic food chain. At least 25% may have a high level of toxicity, 32.5% are intermediate and 10% are doubtful. Major results concern: (1) high risk species (Caranx bartholomaei, C. lugubris, Lutjanus apodus, L. jocu, Gymnothorax funebris, G. moringa, Mycteroperca venenosa, M. tigris, Epinephelus morio, Sphyraena barracuda); (2) intermediate species (Caranx latus, C. ruber, Lutjanus buccanella); (3) low risk species (Balistes vetula, Haemulon album, Priacantus arenatus, Alphestes afer). Occasionally other species or new species are involved Etelis oculatus, Lutjanus analis, Pristipomoides macrophtalmus, Rhomboplites aurorubens, Haemulon album, Scarus vetula.(ABSTRACT TRUNCATED AT 250 WORDS)


Evolution of Gambierdiscus toxicus populations in the coral reef complex of Mayotte Island (SW Indian Ocean) during the 1985-1991 period.

Evolution of the Gambierdiscus toxicus populations during the 1979/1985-1991 period shows an increase of the average densities until 1988-Sept. that seems linked with climatic parameters (insolation, rainfalls) but mainly with anthropogenetic disturbances. After a bloom the populations are now stabilized at a level higher than at the beginning of the monitoring. Without clear correlation, Gtx densities seems associated to physical and chemical features of the lagoonal and reefal waters.


Are Streptomyces bacteria involved in the ciguatoxicity of the surgeon fish Ctenochaetus striatus?

Several Streptomyces strains have been isolated from the digestive tract of the herbivorous fish C. striatus, a preeminent ciguateric fish of Polynesian waters. In order to study the possible role played by these bacteria in the toxicity of this fish, the quantitative and qualitative distributions of these isolates within toxic and non toxic fish are compared. The preliminary results are discussed.


Light and electron microscopic observation of experimental palytoxin poisoning in mice.

The effects of palytoxin on young male ICR mice were compared with the combined effects of palytoxin and ouabain or those of several cations as well as the effects of potassium. The target organs of palytoxin were the heart, kidney, pancreas, small intestine and liver. Pathomorphological changes of the heart induced by palytoxin were similar those of a lethal dose of KC1. However, the KC1-treated animals did not show any changes in the kidney. Mice given ouabain at doses up to 5 mg/kg also showed similar injuries in proximal as well as distal convoluted urinary tubules, while the heart of mice given ouabain at the same doses showed no discernible morphological changes. Ouabain 5 mg/kg did not influence the severity of injuries both in the heart and kidney induced by palytoxin at 4 micrograms/kg. Therefore, it may be assumed that palytoxin poisoning is a symptom-complex of hyperkalemia and causes a profound inhibition of Na+, K(+)-ATPase.


Chronic in utero beta-blockade alters fetal lung development.

Pregnant rats received propranolol (5 or 10 mg/kg/day) from day 10 of gestation; controls were untreated. Lung wet:dry weight ratios were increased in treated fetuses delivered by hysterotomy at day 21; no difference was seen at birth after vaginal delivery. On subsequent days, treated pups exhibited higher wet:dry weight ratios, implying impaired postnatal lung water clearance. Surfactant pools were decreased proportionately at both doses. Ongoing surfactant synthesis was unaffected at either dose. Baseline secretion was reduced for those exposed to 10 mg/kg/day. Secretory response to beta-agonist stimulation was impaired in both treatment groups. Chronic beta-blockade alters fetal lung water clearance, surfactant stores, and secretory response to beta-agonists.


Two RNA-binding motifs in the double-stranded RNA-activated protein kinase, DAI.

The protein kinase DAI, the double-stranded RNA-activated inhibitor of translation, is an essential component of the interferon-induced cellular antiviral response. The enzyme is regulated by the binding of activator and inhibitor RNAs. We synthesized DAI in vitro and located its RNA-binding domain within the amino-terminal 171 residues. This domain contains two copies of an RNA-binding motif characterized by a high density of basic amino acids, by the presence of conserved residues, and by a probable alpha-helical structure. Deletion of either of the two motifs prevents the binding of dsRNA, but their relative positions can be exchanged, suggesting that they cooperate to interact with dsRNA. Clustered point mutations within the RNA-binding motifs and duplications of the individual motifs indicate that the first copy of the motif plays the more important role. Mutations that impair binding have similar effects on the binding of double-stranded RNAs of various lengths and of adenovirus VA RNAI, implying that discrimination between activator and inhibitory RNAs takes place subsequent to RNA binding.


Age related decline in the expression of proliferating cell nuclear antigen in human diploid fibroblasts.

Proliferating cell nuclear antigen mRNA and protein levels were determined in human diploid fibroblasts of different in vitro ages as they progressed through the cell cycle. Cells were analyzed at G0; at various stages of G1, including the G1/S interface; and during S. At all in vitro ages, PCNA message levels were low to undetectable at G0, were evident 8 to 12 h following entrance into G1, peaked at G1/S and declined during S phase. Message levels were 2-3-fold lower in older populations at all stages of the cell cycle tested. PCNA protein increased from G0 through S phase in both age groups with 2-3-fold less being found in older cells. The decline in PCNA mRNA in older populations was not the result of changes in mRNA turnover or transcription. The results suggest that the reduction in PCNA expression is due to an age related alteration in a post-transcriptional regulatory function. The decline in the expression of the PCNA gene would contribute to the inability of older cells to initiate replicative DNA synthesis.


[Interactions of the macrocellular neurosecretory system of the hypothalamus and the endocrine pancreas of rats in adaptation to hypoxia].

Daily hypoxia (6 h, 6000 m) changed the functional state of endocrine pancrease of male and female Wistar rats. The actions of hypoxia on functional state of supraoptic (SO) and paraventricular (PV) nuclei of hypothalamus and islet cells of endocrine pancreas were examined using immunocytochemical, histochemical, morphometric and radioimmunoassay methods. Increase of insulin biosynthesis in beta cells and glucagon secretion of alpha cells, and decrease of the somatostatin contents in delta cells of pancrease islets have been investigated. The functional activity of vasopressinergic magnocellular subnucleus of PV increased, but that of SO decreased with reduction of vasopressin blood concentration at the same time. The functional state of oxytocin synthesis subdivisions of PV and SO were sex dependent, but the oxytocin contents in median eminence increased.


Cellular immune and cytokine pathways resulting in tissue factor expression and relevance to septic shock.

Cells of monocyte lineage serve as effector cells in the cellular immune response. In addition, they respond to LPS and cytokines with activation and expression of inflammatory effector gene products similar to those elicited by the antigen driven response. The response to antigen proceeds at the T helper cell level through two independent forms of cellular collaboration, contact and lymphokine. We review the control of expression of the Tissue Factor (TF) gene and the function of the TF protein. The enhanced initiation of transcription of the TF gene appears to require engagement of a 56 bp LPS Response Element, an enhancer that is engaged by both AP-1 type heterodimeric complexes as well as NF kappa B like heterodimeric complexes. Dissociation of NF kappa B from Ig kappa B by cytokine and LPS stimulation, and possibly activated T cells, may represent a common pathway to induction of the TF and other inflammatory genes. Enhancement of expression of TF is observed upon adhesion of Mo to endothelial cells and extracellular matrix proteins, as well as upon engagement of leukocyte integrins. The biological effects that follow from expression of TF by vascular cells have been resolved by analysis of function aided by the use of recombinant full length TF and truncated surface domain of TF. The rules of assembly of the cognate ligands of TF, namely the zymogen plasma factors VII and the serine protease factor VIIa, with the soluble surface domain of TF in free solution, in the presence of phospholipid surfaces and cell surface and of the anchored TF molecule have been described. It is evident that assembly of the surface domain of TF with VIIa to form the binary TF.VIIa complex induces a significant increase in the Kcat of the catalytic domain of VIIa for small peptidyl substrates and more profoundly for protein substrate. This provides substantial evidence for an allosteric effect on the catalytic cleft of VIIa that is imparted by binding to TF, its cognate catalytic cofactor. It is also evident that the TF.VIIa complex is proteolytically active and can activate the zymogen plasma factor X to the serine protease Xa in free solution, inferring that extended substrate recognition by induced structural loci of the TF.VIIa complex are created from either or both proteins to constitute a new recognition structure. It is also evident that association of X with charged phospholipid surfaces enhances the proteolytic activation of this zymogen by increasing recognition and susceptibility of the sessile peptide bond deduced from the markedly decreased Km and increased Kcat.(ABSTRACT TRUNCATED AT 400 WORDS)


[Thrombosis prophylaxis using plasmin and its combination with alpha-adrenoreceptor antagonists].

Using two models of experimental thrombosis (arterio-venous shunt and Wessler's model) the effect of plasmin and its combination with alpha-adrenoreceptor antagonists on the formation of thrombus was studied on white rats. It was established that the efficacy of prophylactic of thrombosis by plasmin only was low: middle ball of thrombosis was 2.5-3.0. The combination of plasmin with alpha-adrenoblockers dihydroergotoxine or prazosin under these conditions is most efficient against the formation of thrombus (middle ball of thrombus in this case was 0.8-1.1). Prazosin under certain conditions have some advantages.


[Effect of dietary polyunsaturated fatty acids on the content and metabolism of glutathione in rat kidney].

The effect of dietary polyunsaturated fatty acids (PIFA) upon the content of reduced glutathione (GSH) of the kidney was studied in 32 male Wistar rats. Two equal size groups were fed diets supplemented with either 10% or 18% corn oil. Sixteen hours before death, half of each experimental group was submitted to fasting. The content of GSH and the activity of gamma glutamyl transpeptidase (GGTP) and gamma glutamyl cysteine synthetase was determined in kidney tissue. Fasting led to a reduction of GSH from 3.21 +/- 0.54 to 1.25 +/- 0.20 mumol per gm in the group fed 10%. PIFA. Equivalent figures for the group fed 18% PIFA were 3.49 +/- 0.54 and 0.49 +/- 0.08, respectively. GGTP activity increased significantly after fasting but no differences were observed according to level of PIFA intake. The exaggerated reduction of GSH during fasting after a high PIFA intake may expose the animals to risk of cell damage induced by peroxides or other oxidating agents.


[Familial acromegaly. Apropos of a case. Review of the literature].

Two brothers and a sister with acromegaly--one of them with acromegalogigantism--are described. They all presented pituitary adenomas, and the diagnosis was made between the ages of 17 and 29. There was no feature of multiple endocrine neoplasia. The familial investigation consisted of detailed interrogation, basal hormonal evaluation and HLA determination (haplotypes A and B) in 14 members, including the patients themselves. Despite basal plasma GH levels ranging from 8.00 to 10.00 ng/ml in 3 other family members, the normality of both GH response to induced-hyperglycemia and CT-imaging of the pituitary gland excluded the diagnosis of acromegaly in these subjects. No correlation with the HLA haplotypes was observed. Differential diagnosis with familial multiple endocrine neoplasia (MEN type 1) is discussed. Previous reports of familial acromegaly are reviewed and analysed. It appears that familial acromegaly may be considered as a specific entity for two main reasons: 1) owing to the low incidence of acromegaly in the general population, familial cases are unlikely to be fortuitous. 2) most of the reported cases share some common clinical features, such as a male predominance, a high incidence of acromegalogigantism, and the presence of a pituitary macroadenoma. However, the primitive disorder and the genetic transmission of the disease are still unknown.


Gene expression during cardiac development.

The vertebrate heart forms as two concentric epithelial cylinders of myocardium and endocardium separated by an extended basement membrane matrix commonly referred to as cardiac jelly. Subsequent maturation involves a complex series of events including asymmetric changes in cell shape and division which contribute to bending and the formation of the bulboventricular loop, the formation of specialised tissues including endocardial cushion tissue of the atrioventricular (AV) and outflow tract regions, the development of conductive tissue and myocyte maturation leading to the overall pattern of expression characteristic of mature heart muscle. These processes depend on a precise spatial and temporal control of gene expression both of genes encoding regulatory molecules and those encoding structural components of the heart. In this chapter we address three aspects of cardiac development, namely, the determination of cell fate during formation of endocardial cushion tissue in the embryonic heart, transitions in troponin gene expression during fetal myocyte maturation, and the use of cloning techniques based on the polymerase chain reaction for identifying transcription factors present in the heart.


[Erythrocyte membrane transport of amino acid precursors of monoamines in schizophrenic patients. Comparison with depressive patients].

The study concerned 72 schizophrenic and 200 depressed patients hospitalised between 1983 and 1990. The erythrocyte membrane transports (EMT) of L-tyrosine and L-tryptophan (at 37 degrees, 0 degrees and 37-0 degrees) of schizophrenics without treatment nor depression were different compared to controls and depressed patients. The schizophrenics under neuroleptic treatment and/or depressed showed same means of EMT values as depressed patients. The slopes of the correlations between EMT of tyrosine or tryptophan at 37 degrees, 0 degrees and 37-0 degrees, as well as that between plasma levels of these amino acids, were parallel. However the slopes of the correlations between EMT of tyrosine and tryptophan were different according to the subgroups of patients: the perturbations of EMT were related to the clinical characteristics. In depressed patients and in schizophrenic patients under neuroleptic treatment and/or depressed, little changes in EMT of tyrosine were related to high changes of EMT of tryptophan.


[Visual and motor functions in schizophrenic patients].

In the present work, visual and motor functions have been explored in 26 chronic schizophrenic patients, and 7 acute schizophrenic patients, compared with 26 normal controls, by means of the Bender-Gestalt Test. Parameters under consideration were: Form distortion, rotation, integration, perseveration, use of space, subtle motricity, score (global parameter), and time employed. As regards distortion and rotation there have been highly significant differences between chronic patients and control group. Among acute patients, it was observed that perseveration was also highly significant. Conversely, integration and use of space did not differ significantly among the three groups involved. The global score, resulting from all the above mentioned parameters showed important differences between both patient groups on the one hand, and control group on the other hand. Taking into account that patients were being administered neuroleptic drugs, it can safely be said, however, that the Bender-Gestalt Test allows to recognize alteration in perceptual closure consistent with a loss of the objective structure of perceived phenomena, in both chronic and acute patients.


Genetic aspects of multidrug resistance.

Gene amplification is responsible both for dihydrofolate reductase induced methotrexate resistance, and for the P-glycoprotein encoding multigene family induced multidrug resistance. The 6 pairs of hydrophobic regions of the P-glycoprotein fold up in a snake-like structure through the lipidic layers of the cell membrane. Other detoxification mechanisms include the glutathione S-transferase 'pi', but without gene amplification.


Neural, hormonal, and paracrine regulation of gastrin and acid secretion.

Physiological stimuli from inside and outside the stomach coverage on gastric effector neurons that are the primary regulators of acid secretion. The effector neurons comprise cholinergic neurons and two types of non-cholinergic neurons: bombesin/GRP and VIP neurons. The neurons act directly on target cells or indirectly by regulating release of the hormone, gastrin, the stimulatory paracrine amine, histamine, and the inhibitory paracrine peptide, somatostatin. In the antrum, cholinergic and bombesin/GRP neurons activated by intraluminal proteins stimulate gastrin secretion directly and, in the case of cholinergic neurons, indirectly by eliminating the inhibitory influence of somatostatin (disinhibition). In turn, gastrin acts on adjacent somatostatin cells to restore the secretion of somatostatin. The dual paracrine circuit activated by antral neurons determines the magnitude of gastrin secretion. Low-level distention of the antrum activates, preferentially, VIP neurons that stimulate somatostatin secretion and thus inhibit gastrin secretion. Higher levels of distention activate predominantly cholinergic neurons that suppress antral somatostatin secretion and thus stimulate gastrin secretion. In the fundus, cholinergic neurons activated by distention or proteins stimulate acid secretion directly and indirectly by eliminating the inhibitory influence of somatostatin. The same stimuli activate bombesin/GRP and VIP neurons that stimulate somatostatin secretion and thus attenuate acid secretion. In addition, gastrin and fundic somatostatin influence acid secretion directly and indirectly by regulating histamine release. Acid in the lumen stimulates somatostatin secretion, which attenuates acid secretion in the fundus and gastrin secretion in the antrum.


The multiple drug resistance gene, MDR1: expression at the protein and RNA levels.

A comparison of three different approaches to detect MDR1 expression in myeloid leukemia cells was undertaken. With respect to the 4 different antibodies studied, a high proportion of false positive reactions were detected. Substantial discordance between MDR1 expression as indicated by Northern blot analysis, PCR, and immunohistochemistry was found. These findings complicate the clinical interpretation of data derived from these methods.


Short communication: possible activity of beta-carotene in patients with the AIDS related complex. A pilot study.

In a pilot single blind study, beta-carotene (BC) supplementation produced, in ARC patients under current treatment, apparent recovery from asthenia, fever, nocturnal sweating, diarrhoea, loss in weight, and led as a result to an improvement in general health and working efficiency, but not to an improvement in multiple district lympho-adenopathies. Nevertheless, BC appeared to prevent progress to AIDS and, in addition, to lower the effective dosage of AZT used in one case of ARC developed into AIDS, producing a recovery from opportunistic infections and an inhibition of Kaposi sarcoma diffusion, in line with a two-fold rise in CD4 counts.


The H2-receptor antagonist era in duodenal ulcer disease.

This paper reviews the remarkable impact of H2-receptor antagonists on duodenal ulcer management. The development and the scientific rationale of these agents are presented, and efficacy and safety aspects in the short- and long-term treatment of duodenal ulcer disease discussed. Attention is focused on the possible role of "acid rebound" in ulcer relapse following the withdrawal of therapy and on the clinical relevance of prolonged suppression of acid secretion in patients on long-term therapy.


Effects of heat treatment on mechanical properties of base metal wrought wire clasps.

The purpose of this study is to determine the effects of heat treatment and soldering on the change of shape and mechanical properties of cobalt-chromium-nickel alloy wrought wire clasps. The change of distance between the tips of the clasp arm was measured and mechanical properties were examined using the bending test. The following results were obtained. 1) By heat treatment at 500-700 degrees C for 10 minutes, bending rigidity and deflection at the proportional limit of the clasp arm increased significantly (p < 0.01), while permanent deformation after the bending test decreased considerably (p < 0.01). Concerning the deformation of clasp arms by heating, the distance between clasp tips increased remarkably above 500 degrees C (p < 0.01). 2) These mechanical properties of clasp arms were improved both by electric resistance soldering with silver solder and by heat treatment at 500 degrees C for 10 minutes after soldering. From these results, it was concluded that electric resistance soldering and adequate heat treatment were very effective to improve the mechanical properties of the clasp arm, especially to increase the deflection at the proportional limit and reduce the permanent deformation.


Influence of dimensional factors and heat treatment on permanent deformation of wrought wire clasps.

The purpose of this study is to examine the fatigue profiles of wrought wire clasps during the clinical use. Cobalt-chromium-nickel alloy wires were bent into circular beams, which dimensions and fabrication methods were similar to the clinical cases. Deflections of 0.5 mm in a normal direction were applied 10,000 times to the tips of clasp arm and permanent deformations were measured. The following results were obtained. 1) The clasp arms with larger cross sectional diameter, shorter length and smaller radius of curvature showed larger amounts of permanent deformation. 2) The amounts of permanent deformation of the clasp arm remarkably decreased by electric resistance soldering and decreased further more by heat treatment at 500 degrees C for 10 minutes after soldering regardless of the number of deflection. From the results of this study, it was concluded that dimensional factors and heat treatment influenced the permanent deformation of the wrought wire clasps remarkably. Therefore, considering these factors, wrought wire clasps could be designed to reduce permanent deformation.


P-glycoprotein expression in refractory hematological neoplasms and circumvention of resistance with verapamil or cyclosporine A containing protocols.

Either p-glycoprotein (pgp) or the encoding gene mdr1 expression has been reported to be correlated with multidrug resistance and poor treatment response. To investigate the incidence of pgp in refractory hematological neoplasms we analyzed malignant cells from 40 patients by an immunoperoxidase method using the monoclonal antibody C219. Pgp was positive in 75% of acute nonlymphoblastic leukemia (ANLL) and 50% of acute lymphoblastic leukemia (ALL). Pgp positivity was similarly distributed in both Tdt (-) and (+) ANLLs (64% versus 100%). Addition of Verapamil (VRP) (12 patients) or Cyclosporine A (CsA) (7 patients) to the previous chemotherapy protocol resulted in complete response in 7 (58%) and 3 (43%) of the patients respectively. Partial response was observed in one patient who received CsA. Both chemosensitizers were tolerated well with few reversible side effects. The preliminary results of this study have been presented in the 15th International Cancer Congress, August 1990 Hamburg, Germany.


Memory consolidation of a habituation task: role of N-methyl-D-aspartate, cholinergic muscarinic and GABA-A receptors in different brain regions.

1. The immediate post-training microinjection of the N-methyl-D-aspartate receptor antagonist amino-5-phosphonopentanoic acid (5 micrograms) or of scopolamine, the cholinergic muscarinic antagonist (2 micrograms), into the dorsal hippocampus of rats caused retrograde amnesia for habituation to a novel environment, as measured by the number of rearings and crossings performed in a test session. In contrast, picrotoxin (0.08 microgram), the indirect GABA-A antagonist, caused retrograde memory facilitation. 2. Receptor agonists administered into the hippocampus had effects opposite to those of the respective antagonists: glutamate (5 micrograms) and oxotremorine (2 micrograms) enhanced memory and muscimol (0.03 microgram) was amnestic. 3. Aminophosphonopentanoic acid, scopolamine and picrotoxin had no effect when injected into the amygdala or medial septum. Our result contrasted with the recent report of an inhibitory avoidance task in which these drugs, at the doses used here, were effective when injected post-training into any of the three structures. 4. These findings suggest that similar neurotransmitter mechanisms operate in different brain regions in order to regulate memory consolidation processes; however, there is a specialization of these brain regions in relation to different types or components of memory.


Electrophysiological effects of somatostatin at the supraventricular level of isolated guinea pig hearts.

1. The objective of the present study was to evaluate the electrophysiological effects of the peptide somatostatin (SST) at the supraventricular level in isolated guinea pig hearts. 2. ECG recording from isolated hearts perfused by the Langendorff method indicated that 1.0 microM SST induced a decrease in heart rate from 174 +/- 15 to 157 +/- 9 bpm (N = 6, P < 0.05), blocked AV conduction (the PR interval increased from 92 +/- 11 ms to 106 +/- 5 ms, N = 5, P < 0.05) and increased the QTc interval from 210 +/- 0 to 232 +/- 4 ms (N = 5, P < 0.05). The supraventricular effects of SST, particularly upon the AV conduction, were potentiated by a reduction in calcium concentration from 2.5 to 0.5 mM in the perfusing solution. Thus, 1.0 microM SST induced 2nd degree AV conduction block progressing to AV dissociation in 75% of the hearts in the low calcium medium instead of the first degree conduction block observed in all hearts in normal calcium medium. 3. His bundle electrogram evidenced a complete A-H dissociation without significant change in the H-V interval and microelectrode studies showed a complete abolition of the AV node action potential in the presence of 1.0 microM SST. Both results demonstrate that the site of AV conduction block induced by SST is at the AV node. 4. All the supraventricular effects of SST were transitory, subsiding within about 10 min of hormone exposition, showing desensitization. 5. The effects of somatostatin here described were not blocked by 10 microM atropine, indicating that they are not mediated by muscarinic receptors. 6. These data provide a direct electrophysiological demonstration of the supraventricular effects of SST, and suggest that this peptide decreases calcium influx during the action potential.


The X-linked dystonia-parkinsonism syndrome (XDP): clinical and molecular genetic analysis.

Dystonia and parkinsonism are two major representatives of movement disorders. The X-linked dystonia-parkinsonism syndrome (XDP) serves as a model system for the study of both dystonia and parkinsonism since both symptom complexes occur together and are inherited as Mendelian traits with very high penetrance. XDP, which is endemic to the Philippine island of Panay, originated by a single mutation ("genetic founder effect"), thus assuring homogeneity of the disorder at the molecular level. The disease locus, DYT3, has been assigned to the proximal long arm (Xq12-21.1) of the human X chromosome. A strategy is described to isolate this gene by positional cloning. The rationale of this strategy, the major methods involved and technical terms are explained.


DNA fingerprints of Pseudomonas spp. using rotating field electrophoresis.

Rotating field electrophoresis (RFE) was applied to evaluate the usefulness of this technique for identification of several Pseudomonas strains with suspected importance in deliberate releases. Genomes of common wild-type or genetically modified strains of Pseudomonas fluorescens, Pseudomonas stutzeri, Pseudomonas putida and Pseudomonas aeruginosa were digested with rare-cutting restriction endonucleases and subjected to pulsed field gel electrophoresis. Restrictions with SpeI or XbaI produced 11-28 large DNA fragments in the range of 50-500 kb pairs. The specific genomic fingerprints were different for most strains of the same species, but identical for closely related strains. Differences were not affected by the presence of natural or genetically modified plasmids.


Neuroendocrine regulation of immunity: the effects of noradrenaline in Xenopus laevis, the South African clawed toad.

A functional association between the peripheral nervous and the immune system in Xenopus laevis, the South African clawed toad, is demonstrated. This association involves the neurotransmitter noradrenaline (NA), produced and released by the sympathetic nerves of the spleen. Chemical sympathectomy prior to immunization reduces splenic NA, and decreases thymus-dependent (TD), but increases thymus-independent (TI), antibody responses. Immune challenge with representatives of the three antigen classes affects splenic NA levels differentially. Thus, the modulatory effect of NA on immunity will depend on the immunogen used. Carrier-priming of helper function in TD responses stimulates a transitory NA release in the spleen, while subsequent immunization activates a more prolonged release. The two types of challenge differ in the antigenic dose given. The effects of NA also depend on the time when it is applied. If used early in the in vivo TD response, antibody production is increased, but if given later, suppressor function is stimulated, thus decreasing antibody production. NA increases both amplifying and suppressing T cell functions in TD responses through stimulation of the alpha 2 adrenoceptor. Alpha 2 adrenoceptor stimulation decreases, and beta adrenoceptor stimulation increases, anti-TNP reactivity. Since an alpha 2 receptor agonist does not affect lectin-stimulated T cell mitogenesis, while a beta receptor agonist depresses it, NA appears to up-regulate T cell functions by affecting their maturation, rather than their clonal expansion.


Behavioral effects of gut hormones in neonatal rats: I. Somatostatin administration during the first postnatal week.

This exploratory study attempted to uncover behavioral and physical outcomes of changes in the peripheral SMS system in the first postnatal week. On postnatal days 1-7, Sprague-Dawley rat pups received daily s.c. injections of Somatostatin (SMS; 8 or 40 micrograms/kg), saline, or CPP-1 (8 or 40 micrograms/kg), a putative SMS receptor antagonist. Physical growth and neurobehavioral development of the pups, assessed on days 3, 6, 9 and 12, were not affected, in 3 separate replications (n = 11/treatment/replication). In contrast, neonatal CPP-1 (40 micrograms/kg) reduced separation distress on day 14, as measured by ultrasonic vocalization and activity. In addition, neonatal SMS (40 micrograms/kg) tended to impair learning on a milk-rewarded Y-maze on days 15-16. These findings support further examination of the potential role of SMS in behavioral development.


Monozygotic twins with discordant sex.

A nine-year-old girl with short stature was referred to the department of pediatrics at Kyushu University. The clinical diagnosis was Turner syndrome; karyotypic analysis performed on peripheral blood, using GTG techniques, demonstrated a 45,X/47,XYY (17:83) mosaicism. Her twin brother, a phenotypically normal male, had the same karyotype; 45,X/47,XYY (3:97) on peripheral blood. Their skin fibroblast karyotypes showed the same mosaicism, ie. 45,X/47,XYY (41:59 and 31:69 respectively). On eleven biochemical genetic markers the twin pair were concordant, thus the likelihood of monozygosity was 0.99527034. In addition, the analysis of variable number of tandem repeat (VNTR) markers revealed the likelihood of monozygosity to be 0.99944386. The most plausible explanation of the X/XYY mosaicism was nondisjunction of the Y in the first cleavage division of the 46,XY zygote. A disproportionate rate of cell populations with 45,X and 47,XYY in the twinning process of the X/XYY embryo, especially in the germ lines, would result in discordant sex in twin pairs.


Evidence for two independent mechanisms of GABA release induced by veratridine and glutamate in monolayer cultures of chick embryo retinal cells.

GABA is a major inhibitory neurotransmitter in the central nervous system, including the retina. In the present paper we present evidence for the existence of two independent mechanisms for GABA release in cultured retina cells. Eight-day-old chick embryo retinas were dissociated and plated in 35-mm plastic dishes and cultured for 3 or 7 days at 37 degrees C. An increase of 3 to 5-fold in GABA release was observed in cultures of 3 or 7 days in vitro preloaded with 0.5 microCi [3H]GABA and stimulated with glutamate (100 microM) or veratridine (100 microM). Tetrodotoxin (1 microM) blocked the release induced by veratridine but not by glutamate. In contrast, the non-N-methyl-D-aspartate (NMDA) glutamate antagonist 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX, 100 microM) was able to inhibit GABA release promoted by glutamate but not by veratridine. These results indicate that depolarization of retinal cells by opening of voltage-dependent sodium channels or activation of non-NMDA glutamate receptors can trigger intracellular events that lead to calcium-independent GABA release.


The role of melatonin in the antipsychotic and motor-side effects of neuroleptics: a hypothesis.

Three phenomena concerning the antipsychotic action of classic neuroleptic drugs have not been adequately explained by the dopamine hypothesis: (1) administration of neuroleptic drugs is commonly associated with an initial period of 3-6 weeks prior to demonstration of antipsychotic effects; (2) similarly, neuroleptic-induced Parkinsonism commonly emerges only after several weeks of neuroleptic therapy; (3) moreover, Parkinsonism may disappear despite continuous neuroleptic treatment. An understanding of these phenomena might shed new light into the nature of the antipsychotic actions of these agents, and hence the pathophysiology of schizophrenia. We propose that the increase in melatonin secretion, which occurs with the initiation of neuroleptic therapy, may be responsible for the delay in the antipsychotic effects of neuroleptics and may also account for the lag in the development of drug-induced Parkinsonism as well as its disappearance. The implications of this hypothesis for the treatment of schizophrenia and the prophylaxis of drug-induced Parkinsonism are discussed.


Brain serotoninergic stimulation reduces the water intake induced by systemic and central beta-adrenergic administration.

1. This study was undertaken to determine if the stimulation of central serotoninergic receptors affects the thirst-inducing action of systemically or intracerebroventricularly (icv) injected isoproterenol. 2. Male Wistar rats weighing 220-300 g were used in groups of 10-14 animals each. Normally hydrated rats implanted with a delay cannula into the third ventricle were injected icv with the 5HT1C/5HT2 agonist MK212 (50 nmol/2 microliters) prior to administration of isoproterenol sc (330 micrograms/kg body weight) or icv (10 and 25 and 50 micrograms/2 microliters). 3. Icv injections of MK212 reduced the water intake induced by isoproterenol injected systemically (56%) and by the two lowest doses of isoproterenol injected icv (76 and 86%, respectively). 4. The results suggest that the central serotoninergic system modulates the central beta-adrenergic system involved in water intake. 5. Taken together with previous results showing that the activation of 5HT1C/5HT2 receptors promotes a reduction of the dipsogenic response evoked by water deprivation or by icv injection of angiotensin II or carbachol, the present data suggest that the central serotoninergic system plays a ubiquitous role in the modulation of water intake behavior.


Identification of mechanisms that may modulate the role of lipoprotein(a) in thrombosis and atherogenesis.

In this report, we review recent findings concerning the identification of mechanisms that may modulate the role of lipoprotein(a), or Lp(a), in thrombosis and atherogenesis. Lp(a) binds to surface-immobilized plasmin-modified fibrin, thus providing a mechanism for incorporating Lp(a) into the vessel wall. We found that homocysteine and other sulfhydryl-containing amino acids markedly increase the binding of Lp(a) to plasmin-modified fibrin. Our results suggest that homocysteine alters the structure of Lp(a) to expose lysine-binding sites on the apolipoprotein(a) portion of the molecule, and thus provide a potential biochemical link between thrombosis and atherogenesis. We also found that transglutaminases catalyze the incorporation of primary amines into Lp(a). Studies in cell culture systems have found that Lp(a) stimulates endothelial cells to synthesize and release plasminogen activator inhibitor-1. Further, Lp(a) inhibits the activation of transforming growth factor-beta in a coculture of bovine endothelial and smooth muscle cells.


[Fragile X syndrome: current knowledge].

Fragile X syndromes is a disease characterized by the association of mental retardation and dysmorphic features to a fragile site on Xq27-3. It is a frequent genetic disorder (1 in 1,500 males) recognized only 20 years ago but remaining difficult to understand, because its transmission among generations does not correspond to the classical model of recessivity linked to chromosome X. In fact, carrier females can express the disease and transmitting males can be normal. With DNA probes, molecular biology has contributed to genetic counselling and prenatal diagnosis. Restriction polymorphisms have long been used to study the inheritance of fragile X syndrome and DNA markers' analysis improved risk estimates for carriers. From a clinical viewpoint, there was a need for more closely linked probes to help in prenatal diagnosis and to assess carrier status and hence reduce risk of recombination. In 1991, new probes allowed direct diagnosis of the Fra (X) mutation and a gene was sequenced. Nevertheless the understanding of the mechanism involved in the underlying mutation is still unknown. Geneticists, cytogeneticists and biologists must collaborate further to elucidate the fragile site mystery.


[Hereditary porphyria and acquired porphyria in the child. Five case reports].

Two cases of inherited porphyrinopathies and three cases of acquired porphyrinopathies are described. The two inherited cases were cutaneous porphyrias with 50% reduction of enzyme activities: one case of erythropoietic protoporphyria in a 2 year-old male and one case of familial cutaneous porphyria in a 7 year-old boy. The three cases of acquired porphyrinopathy included one case of lead poisoning in a 3 year-old boy and 2 cases of hereditary tyrosinemia in 1 and 2 year-old infants. Urinary and erythrocytes porphyrins and precursors (5 aminolevulinic acid and porphobilinogen) levels were used for diagnosis and to follow the response to treatment.


[HIV infection in the child after materno-fetal transmission: early treatment with azidothymidine and prevention of secondary infectious complications].

Twenty-four perinatally HIV infected children received early treatment as soon as the diagnosis of viral contamination was established. In 13 cases (group 1), this diagnosis was based on a viremia and/or antigenemia during the first 6 months of life. In 11 cases (group 2), children were more than 15 months-old and had a positive HIV antibody test. Therapy included azidothymidine (AZT, 400 mg/m2/d) and the prevention of secondary infectious complications with intravenous immunoglobulin and cotrimoxazole. With a median follow-up of 26 months, we reported no case of severe secondary infection and no case of encephalopathy. Hematological side effects of AZT were rarely observed. Only one patient developed anemia. In all other cases, the only hematological abnormality was macrocytosis of red blood cells. Before treatment, the mean value of T4 cells age-adjusted count was 96, 86 and 91%, respectively, for groups 1, 2 and the entire study group. At the time of analysis, these values were 64, 62 and 63% respectively. This decrease was statistically significant for group 1 and for the entire study group, but did not reach statistical significance for group 2. These data show that AZT is probably insufficient as a long-term therapy for HIV infected children. Other therapeutic approaches need to be developed in the future, notably the combination of anti-retroviral drugs.


[Platelet serotonin in infantile autism. Cross-over effects of a dopamine agonist and an antagonist].

In infantile autism, the serotoninergic (5-HT) hypothesis is corroborated by biological dosages and therapeutic effects of fenfluramine which decrease blood serotonin. However other drugs, such as dopaminergic agonists or antagonists, have therapeutic effects. Therefore, we tested the hypothesis that two dopaminergic (DA) drugs have a similar 5-HT effect underlying the therapeutic efficiency. We evaluated in a randomized, double-blind and cross-over study, the effects of a DA agonist (bromocriptine) and a DA antagonist (amisulpride) on platelet 5-HT in infantile autism. The prolactinemia, reflecting the DA action, has been also measured. Nine children, aged from 4 to 13 years, according to the DSM III for infantile autism, received either drug in a random order during four weeks with an in-between placebo period of six weeks. The dosages of platelet 5-HT and serum prolactin were carried out at the beginning and at the end of every phase of treatment (active or placebo) with radioenzymology and radioimmunoassay methods respectively. The principal results on serum prolactin show neither order x treatment interaction, nor order effect but a significant treatment effect (p < 0.01): amisulpride increases serum prolactin whereas bromocriptine decreases according to the usual data. About platelet 5-HT, there is neither order x treatment interaction, nor treatment effect but a significant order effect (p < 0.01). Both drugs increase platelet 5-HT in the first phase of treatment. This order effect could be explained by a remanent effect of amisulpride after 6 wash-out weeks.(ABSTRACT TRUNCATED AT 250 WORDS)


Graves' disease: evolution and prognosis after eight months of treatment with methimazole.

We studied 26 patients with Graves' disease, from a population with sufficient iodine supply, treated with high doses of methyl mercaptoimidazole (MMI) during eight moths. We evaluated: a) their evolution after treatment withdrawal; b) the correlation between evolution and TSH-receptor antibodies (TRAb), thyroid hormone levels, microsomal antibodies (MAb), T3/T4 index and clinical data; c) their prognosis. The patients were followed during 12-60 months, and blood samples were collected before treatment withdrawal. Out of 26 patients, 20 relapsed, with T3/T4 index and TRAb significantly higher than those under remission. The T3/T4 index correlated with TRAb. All the TRAb-positive patients, and only 57.1% of the negatives, relapsed. The relapses were significantly more frequent prior to the 6th month in the TRAb-positive patients than afterwards. The TRAb-negatives who relapsed during that period, showed TRAb and age means significantly higher than those under remission. The TRAb test, as a prognostic marker of evolution, showed a sensitivity of 60% and a specificity of 100%. No significant differences were found between evolution to relapse or to remission and the other parameters. It can be concluded that TRAb and T3/T4 index were different in the group that relapsed from that which remitted, and that a TRAb positive value, at the moment of treatment withdrawal, is a useful marker of relapse.


[Relevant pharmacologic data as a guide for use of beta-blockers in psychiatry].

In addition to their competitive blockade of the beta-receptors, beta-adrenergic-blocking drugs possess ancillary properties that may modulate their clinical effects. Among these properties, beta 1-selectivity, intrinsic sympathomimetic activity, lipid solubility, may affect pharmacokinetic and pharmacodynamic properties of beta-blockers. It could appear that lipid soluble drugs gain access to the Central Nervous System (CNS) more easily. But CNS effects of beta-blockers are probably modulated by other parameters. With those pharmacological data, the authors propose briefly a schematic use of main beta-blockers in psychiatry.


[AIDS and tuberculosis: the immunopathogenic processes].

HIV infection is characterized by CD4+ lymphocyte depletion manifested through the loss of the immune response capacity. The resulting immunodeficit is expressed by the blocking of immune surveillance mechanisms and, thus, by the establishment of favourable conditions to the development of opportunistic infections and/or malignant processes. In tuberculosis, the immunodeficiency associated with HIV infection makes possible the evolution of a latent infection to a clinically manifest disease. Latent tuberculosis is characterized by the intracellular persistence of some metabolically inactive Tb bacillus forms which are incapable of multiplication. The conversion of these inactive into metabolically active forms capable of multiplication is usually neutralized by immunosurveillance mechanisms. The blocking of such mechanisms in case of CD4+ cell depletion will allow the multiplication of metabolically active Tb bacillus forms, and the development of a clinically manifest tuberculosis. CD4+ lymphocyte depletion is the result of facilitating antibodies and certain cytokines, and of some autoimmune processes which also affect the non-infected CD4+ cells. Therefore, it is necessary that Tb chemoprophylaxis in HIV infected subjects should also be addressed to the processes initiating the immune deficit, which include autoimmune mechanisms as well as those facilitating HIV infection.


Antihistamine activity of Bryophyllum calycinum.

1. The juice obtained by pressing the leaves of Bryophyllum calycinum (Crassulaceae) exhibited histamine-blocking activity. 2. The juice contains flavonoid compounds, carbohydrates and mineral salts. A flavonoid fraction (fraction B) obtained by partitioning the juice between n-butanol and water contained the substance responsible for the antihistamine activity. 3. When assayed on the isolated guinea pig ileum, 50 mg/ml juice and 0.15 mg/ml fraction B produced parallel and concentration-dependent rightward displacement of the concentration-response curve to histamine (EC50 (FL): 1.30 (0.26-5.28) x 10(-7) M, 15.80 (5.90-23.30) x 10(-7) M, 12.50 (7.62-14.90) x 10(-7) M, in the absence and presence of 50 mg/ml juice and 12 mg/ml fraction B, respectively) apparently in a competitive manner. The antagonism was specific for histamine, i.e., did not modify the response to acetylcholine, KCl and BaCl2 and was reversible upon washing. Vascular permeability responses of rats to intracutaneous 1.0, 5.0 or 10.0 micrograms histamine were decreased by about 20-25% in animals pretreated with 4 ml/kg of juice or with 12 mg/kg fraction B. The juice (4 ml/kg) protected guinea pigs from death by asphyxia induced by 5 mg histamine and the protection lasted at least 1 h. 4. However, since the juice was ineffective in protecting the gastric mucosa from histamine-induced ulceration, we conclude that the antihistamine effect of the juice and fraction B was produced by blockade of H1 and not H2 receptors.


Sequence and secondary structure comparisons of ITS rDNA in mosquitoes (Diptera: Culicidae).

Sequences of the internal transcribed spacers (ITS1 and ITS2) of the mosquito Aedes aegypti, and the ITS2 of six related species, A. simpsoni, A. albopictus, A. vexans, A. triseriatus, Haemagogus mesodentatus, and Psorophora ferox are reported. Intraspecific variation in A. aegypti ITS1 is 1.07% among four clones from three individuals, and in the ITS2 is 1.17% among 15 clones from four individuals. In A. simpsoni, intraspecific ITS2 variation is 0.46% among 10 clones from a single individual. Alignment of the ITS2 sequence of the seven species reveals several homologous domains. Secondary structure predictions for the ITS2 region indicate that these domains base pair to form a core region central to several stem features. The sequence outside the ITS2 homologous domains tends to be GC-rich and characteristically slippage generated; these areas preserve or add to the stem length of the predicted secondary structures. These ITS2 intraspacer variable regions resemble previously described expansion segments of the 28S gene region. Evolutionary analysis of the ITS2 of these species, using both sequence and secondary structure information, leads to the prediction of divergence in the mosquito tribe Aedini that is not clearly reflected in current taxonomic designations.


Distinguishing between monoclonal rearrangements and allelic forms of the immunoglobulin lambda light chain constant region genes. Significance in the diagnosis of non-Hodgkin's lymphoma.

Four allelic forms of the immunoglobulin lambda light chain constant region (C lambda) genes are found in the caucasoid population and are recognised by the presence of Eco RI restriction fragments of sizes 8, 13, 18, and 23 kb hybridising with a C lambda probe. The less common allelic forms of the C lambda genes are marked by the 13, 18, and 23 kb fragments, and these may be misinterpreted as rearranged fragments derived from a monoclonal population of B-cells. The 13, 18, and 23 kb alleles result from the insertion of one, two, and three copies, respectively, of a 5.2 kb repeat unit that can be demonstrated by hybridising genomic DNA digested with Hind III with a C lambda probe. Using selected histologically and immunophenotypically well-defined cases, we assessed the usefulness of the 5.2 kb Hind III/C lambda fragment in distinguishing between rearrangements indicative of a B-cell lymphoma and germline configurations representing uncommon allelic forms of the C lambda genes. From these studies, we conclude that Hind III digestion should routinely be performed when using the C lambda probe to assess B-cell monoclonality. Identification of the 5.2 kb Hind III fragment obviates the need to examine DNA from normal peripheral blood granulocytes to exclude allelism of the C lambda genes in cases exhibiting the uncommon restriction fragments after Eco RI digestion.


Nephrotic syndrome and respiratory allergy in childhood.

The etiology and pathogenesis of idiopathic nephrotic syndrome remain obscure. Several investigations have reported a role for allergy in the development and maintenance of this disease, especially in childhood. We have studied 20 pediatric patients with relapses of nephrotic syndrome related in time to respiratory symptoms. Sensitization was demonstrated to one or more allergens in 7 patients with episodes of proteinuria of seasonal tendency. Preventive management with disodium cromoglycate was successful in preventing new relapses in 3 patients; specific immunotherapy was assayed in another 2 without beneficial outcome. There appears to be a pathogenic relationship between respiratory allergy and proteinuria in some cases of nephrotic syndrome.


Abnormal p53 expression in lung neuroendocrine tumors. Diagnostic and prognostic implications.

The diagnostic and prognostic implications of p53 immunostaining have been investigated in 59 pulmonary neuroendocrine tumors, including typical carcinoids (n = 15), so-called "atypical carcinoids" (n = 22), and small cell lung carcinomas (SCLCs; n = 22). Immunocytochemistry was performed on formalin-fixed, paraffin-embedded samples using the monoclonal antibody PAb1801, which has been shown to be suitable for staining fixed and embedded tissue sections. p53 immunoreactivity was restricted to atypical carcinoids (45% of the cases being immunoreactive) and to SCLCs (which were positively stained in 59% of the cases), whereas it was consistently lacking in typical carcinoid tumors. When the group of the so-called "atypical carcinoids" was further reclassified, p53 immunostaining was strictly confined to those cases belonging to the histologically more aggressive subsets (well differentiated neuroendocrine carcinoma subsets II and III). Within the same tumor type, however, p53 immunoreactivity did not correlate with the clinical outcome of the disease and was not predictive of the length of survival. The data indicate that abnormal p53 expression (which is strictly dependent on structural abnormalities of the p53 gene) is detectable in the majority of neuroendocrine carcinomas of the lung and might represent a useful adjunct in the differential diagnosis of pulmonary neuroendocrine neoplasms, particularly in routinely fixed and embedded small bronchoscopic biopsies.


Rapid in situ detection of PCR-amplified HIV-1 DNA.

The low copy number of human immunodeficiency virus 1 (HIV-1) DNA infected cells precludes routine detection by in situ hybridization. The inability to detect cells latently infected by HIV-1 makes difficult the study of factors that induce viral transcription, an essential factor in the development of the acquired immune deficiency syndrome (AIDS). A sensitive and rapid technique to detect HIV-1 DNA could be used as a diagnostic test for AIDS and to differentiate latent versus active viral infection. We describe a 3-h technique whereby HIV-1 DNA is amplified by hot start polymerase chain reaction (PCR) and detected directly in infected cells. The specificity of the assay was demonstrated by double labeling the positive cells with CD4. Using a CR10 HIV-1-infected cell line, the 90% of cells that were HIV-1 DNA positive could be distinguished from the 10% that were actively expressing HIV-1 RNA. The PCR in situ technique should allow for the direct localization of DNA sequences in cells that would otherwise be undetectable by conventional in situ analysis.


Does C-reactive protein modulate T-lymphocyte function in methotrexate-treated rheumatoid arthritis patients?

Thirty-four patients with rheumatoid arthritis were treated with oral methotrexate for 6 months. Methotrexate was given as a single weekly dose of 7.5-10 mg. A correlation between serum concentration of CRP and proportion of CD8+ lymphocytes in peripheral blood was found in this group of patients. This correlation can be described by a linear regression equation. According to the results obtained, CRP suppresses lymphocyte function in patients with RA. This is the consequence of the stimulating effect on suppressor mechanisms.


Identification of donor melanoma in a renal transplant recipient.

A patient with chronic renal failure received a closely matched cadaveric kidney. Approximately 3 months after transplantation, the patient developed a metastatic malignant melanoma. A large retroperitoneal mass consisting of large pleomorphic polygonal neoplastic cells was found close to the donated kidney. This tumor was diagnosed as a malignant melanoma. DNA analysis of this tumor, the donated kidney, and the recipient indicated that the melanoma originated from the donor. Although this is not the first report of a donated melanoma, it is the first report of definitive DNA analysis of the origin of the malignant cells.


A comparison of new nonsedating and classical antihistamines in the treatment of primary acquired cold urticaria (ACU).

The efficacy of the new nonsedating antihistamines loratadine and cetirizine was compared in a randomized, single-blind, crossover, controlled study with that of the classical antihistamines cyproheptadine and ketotifen in seven patients with primary acquired cold urticaria (ACU). The patients received each of the four drugs for 14 consecutive days with a 7-day interval between drugs. We evaluated clinical symptomatology, adverse effects, minimum time of cold contact stimulation required to induce an immediate coalescent wheal (CSTT), and inhibition of histamine-induced wheal response. Both loratadine and cetirizine showed suppression of symptoms with infrequent adverse effects. Important side-effects were observed in patients receiving cyproheptadine. Improvement in CSTT was statistically significant for all drugs compared with baseline values, without differences among them. The histamine-induced skin test was significantly inhibited by all antihistamines. Wheal reductions were 34.6% for loratadine and 50.9% for cetirizine. This study suggests that both loratadine and cetirizine may be effective in the treatment of primary ACU.


[H2 antagonists as inhibitors of cytochrome P-450 in rat liver: in vitro and in vivo effects].

Cytochrome P-50 is a well known participant in the metabolism of xenobiotics as well as an activator or inactivator of hepatotoxic substances and carcinogenic agents. H2 antagonists, cimetidine, famotidine and ranitidine were used to inhibit cytochrome P-450 in rat liver. After 200 mg cimetidine, 85% inhibition of cytochrome P-450 in vitro and 50% in vivo were demonstrated through demethylation of aminopyrine. Inhibition was further confirmed by differential absorption spectra (Type II). The percentage inhibition obtained with famotidine or ranitidine were lower than those obtained with cimetidine. Inhibition of the microsomal oxidative system by cimetidine could lead to decreased production of superoxide radicals and protection against damage induced by toxic agents activated in the liver.


Induction of apoptosis in thymocytes by prostaglandin E2 in vivo.

In vivo administration in mice of a synthetic analog of prostaglandin E2 (PGE2) caused a selective and dramatic decrease of CD4+CD8+ double-positive, CD3/T-cell-receptor-alpha beta(lo) cells in the thymus. This loss was corticosteroid-independent and not affected by Cyclosporin A. The disappearance of CD4+CD8+ thymocytes was strictly correlated with the induction of apoptosis inside the thymus as shown by morphological studies and by the induction of intracellular transglutaminase expression. Considering that PGE2 has been found to be produced by different cell populations inside the thymus, these results indicate that PGE2 may act as endogenous signals for apoptosis during T-cell differentiation.


The acquisition of a memory phenotype by murine CD4+ T cells is accompanied by a loss in their capacity to increase intracellular calcium.

During the process of aging, the fraction of CD4+ T cells with a naive phenotype, that is, Pgp-1- CD45RBHighMEL-14+, decreases in favor of CD4+ T memory cells. Total CD4+ T cells from aged mice displayed a diminished calcium response to anti-CD3 and even ionomycin as compared to the cells from young mice, and this was related to the changed composition of the CD4+ T-cell population. Regardless the age of the donor mice, naive CD4+ T cells effectively increased intracellular calcium, whereas memory CD4+ T cells were impaired in this regard. In addition, a heterogeneity in the differentiation stage of the naive CD4+ T cells was shown by the observation that calcium mobilization in naive CD4+ T cells from young mice was more profound than that in their aged counterparts. These data thus indicate that during the acquisition of a memory phenotype, murine CD4+ T cells lose the capacity to increase intracellular calcium, which in turn may be responsible for the decreased level of IL-2 production by these cells.


Neurochemical mechanisms of memory control.

Modulation of memory trace retrieval in emotiogenic brain structures, cortex and brainstem reticular formation by postsynaptic noradrenergic and dopaminergic drugs was found. At the initial stage of latent inhibition-a most significant mechanism of information selection-memory trace retrieval is retarded in all structures and in the cortex and the zona incerta later on. A haloperidol model of latent inhibition was obtained. Most important role of dopaminergic system in latent inhibition was shown. Inhibition of the GABA-benzodiazepine-ionophore complex by the blockade of GABA-receptors induced by bicuculline, the chloride channels by picrotoxin, the benzodiazepine receptors by flumazenil (R015-1788) and R015-3505 facilitates the memory trace retrieval damaged by amnesic agent. The dopaminergic activation enhances the dominant state and developes conditions for switching on the interferential GABA-ergic inhibition.


Antihypertensive drugs and cardioprotection.

Cardioprotection is a broad term; this short review deals with six aspects: 1. Secondary prevention of myocardial infarction (MI) has been shown for beta-blockers in both early and late intervention studies. Dihydropyridine calcium antagonists are associated with an excess incidence of coronary events, whereas non-dihydropyridines prevent reinfarction provided left ventricular (LV) function is adequate; dihydropyridines tend to increase heart rate and stimulate the sympathetic and renin-angiotensin systems. 2. Primary prevention of MI has been shown for beta-blockers in younger/middle-aged hypertensives but not in the elderly. Diuretics, by contrast, possibly increase the risk of coronary events in younger/middle-aged hypertensives but significantly reduce coronary events in older hypertensives. These results might be explained by the larger, noncompliant left ventricle of the elderly hypertensive, which, in the absence of overt ischemia, responds poorly to beta-blockade (further enlargement with increased wall stress and impaired coronary reserve), while diuretics have the opposite effect. Primary prevention of coronary events in patients with chronic angina is likely to occur with beta-blockers, while studies with calcium antagonists have shown a significant excess of coronary events. 3. Ischemic events occurring during the "vulnerable" period between 7 and 10 AM (when sympathetic activity is maximal) are significantly reduced by beta-blockers but not by calcium antagonists. 4. Stress-induced myocardial necrosis in humans is markedly reduced by beta-blockers. 5. Coronary risk factors, such as elevated blood lipids, hyperglycemia, and insulin resistance, are possibly adversely affected by diuretics and beta-blockers, with the former also increasing heart rate, plasma renin activity, and plasma catecholamine levels.(ABSTRACT TRUNCATED AT 250 WORDS)


Therapy of a case of psychotic personality organization manifesting gender identity disorder.

The author relates his experience with a case of psychotic personality organization manifesting transsexualism spanning about 10 years. This paper presents the case and discusses the psychodynamics together with the course of therapy. The patient was a case of primary transsexualism who fell into hallucinatory-delusional states each time he seriously tried to become a woman. His transsexual wish was identification with his idealized grandmother image, for defense of his helpless and vulnerable self, and an attempt to reestablish his self which was facing a crisis of disintegration due to disorganization of his ego. Over about 4 years of psychoanalytic psychotherapy, the conflict between "becoming a woman" and "taking over as head of the house" was an integral issue. The psychotherapy was brought to a tentative conclusion by the patient giving up the idea of "becoming a woman" and deciding to "take over as head of the house".


Isometric developed tension and histopathology of myocardium of chagasic mice. II.

In a preceding paper we reported the evolution of chagasic cardiopathy in mice inoculated with low number of T. cruzi from 2 days to 75 days post-infection (p.i.). The present work analyzed the contractility, pharmacological response and histopathology of myocardium isolated from chronic chagasic mice from 90 days until 180 days. p.i. Myocardium contractile force reached values similar to controls until 165 days p.i. From this to the end contractility was significantly lower. At 90 days p.i. NE provoked negative inotropic effect or had no effect in 13% of the cases tested. The others had a reactivity to NE similar to normal ventricles. From 105 days until 180 days p.i. NE induced to a positive inotropic effect significantly lower than in normal. ACh effect was significantly smaller from 165 days to the end. Previously ACh ventricles responses were as control. The effects of dibenamine, propranolol and atropine (10-6M) on chagasic ventricles were similar to those observed in normal tissues. At 90 days p.i. the histopathology showed focalized inflammatory infiltrates. At 180 days p.i. fibers fragmentations and loss of typical striated characteristic of cardiac tissue. The abnormal pharmacological response described could be attributed to alterations in cardiac beta and muscarinic receptors probably due to a lower oxygen support. The present paper shows that during chronic Chagas' disease myocardial function and pharmacological reactivity are seriously and definitively compromised.


The effect of jejunal nutrition on pancreatic exocrine function.

Pancreatic juice was continuously diverted from the Wirsungial duct by nasopancreatic drainage of the remnant of the gland after pylorus preserving partial pancreato-duodenectomy in 14 patients. On the 7th postoperative day with stabilized pancreatic secretion the juice was collected in 10 min fractions, while interdigestive secretory phases of the parenchyma were established by volume changes. At the beginning of a phase, 100 ml slightly hyperosmolar (400 mOsm/l) oligopeptide diet with 360 kJ (90) kCal) was given as a bolus injection to another 7 patients or 60 min infusion into the second jejunal loop by fine-needle catheter jejunostomy to another 7 patients. Pancreatic water, bicarbonate, protein, chymotrypsin, peak amylase levels, and integrated secretory responses were measured. It was observed that infusion of the diet did not disturb cycling interdigestive phases and did not increase peak and integrated outputs. Bolus administration interrupted interdigestive phases and stimulated pancreatic water, bicarbonate, protein, chymotrypsin and amylase outputs nonparallelly. On the basis of the data it was concluded that pancreatic secretion seems to be well preserved without duodenal regulatory mechanisms, and continuous jejunal infusion feeding seems to be useful in pancreatic disease and in other postoperative states when pancreas has to be put into rest.


Presynaptic calcium signals during neurotransmitter release: detection with fluorescent indicators and other calcium chelators.

Synthetic calcium buffers, including fluorescent calcium indicators, were microinjected into squid 'giant' presynaptic nerve terminals to investigate the calcium signal that triggers neurotransmitter secretion. Digital imaging methods, applied in conjunction with the fluorescent calcium indicator dye fura-2, reveal that transient rises in presynaptic calcium concentration are associated with action potentials. Transmitter release terminates within 1-2 ms after a train of action potentials, even though presynaptic calcium concentration remains at micromolar levels for many seconds longer. Microinjection of the calcium buffer, EGTA, into the presynaptic terminal has no effect on transmitter release evoked by single presynaptic action potentials. EGTA injection does, however, block the change in calcium concentration measured by fura-2. Therefore, the calcium signal measured by fura-2 is not responsible for triggering release. These results suggest that the rise in presynaptic calcium concentration that triggers release must be highly localized to escape detection with fura-2 imaging. Unlike EGTA, microinjection of BAPTA--a calcium buffer with an equilibrium affinity for calcium similar to that of EGTA--produces a potent, dose-dependent, and reversible block of action-potential evoked transmitter release. The superior ability of BAPTA to block transmitter release apparently is due to the more rapid calcium-binding kinetics of BAPTA compared to EGTA. Because EGTA should bind calcium within a few tens of microseconds under the conditions of our experiments, the inability of EGTA to block release indicates that transmitter release is triggered within a few tens of microseconds after the entry of calcium into the presynaptic terminal.(ABSTRACT TRUNCATED AT 250 WORDS)


The effect of early postoperative nutrition on exocrine pancreatic function.

Subsequent to pancreato-duodenectomy with preservation of the pylorus in 12 patients the effect of parenteral and enteral nutrition on pancreatic secretion were compared. The pancreatic juice was continuously diverted from the Wirsung duct by nasopancreatic drainage. Postoperative feeding was administered by fine-needle catheter jejunostomy in 7 patients and 5 patients received total parenteral nutrition. The pancreatic juice was collected in four-hour fractions and it was analysed for volume, bicarbonate, protein, chymotrypsin and amylase. It has been found that on the first two days after the operation there was a slow increase in the measured values and on the third postoperative day after an abrupt rise the pancreatic secretion became steady. No differences in exocrine pancreatic secretion were observed between the enteral and parenteral methods of feeding. According to these data the two methods seem to be of the same value in the postoperative therapy.


Presynaptic calcium concentration microdomains and transmitter release.

n-Aequorin J, a luminescent protein which responds to calcium concentration changes in the order of several hundred micromoles, was injected into the preterminal fiber in the squid giant synapse. The activation of the presynaptic terminal leading to release of transmitter was accompanied by light emission at well-defined sites at the active zone in the presynaptic terminal. Location of these light emission sites was very much the same from one stimulus to the next, indicating that light emission was triggered by the inward calcium current occurring at specific and invariant locations. The distribution, size and number of these QEDs (quantum emission domains) coincides well with the location and number of active zones in the presynaptic terminal. The results imply that transmitter release is triggered by very well-localized calcium concentration changes that may be as high as several hundred micromoles.


[Schizophrenia and immunity].

In schizophrenia, various modifications of the immune system have been reported. A decrease of interleukin-2 production by T lymphocytes and an increase of IL-2 receptors were observed by several authors. Not only cellular but humoral immunity seems to be modified: apart from the viral hypothesis, an auto-immune hypothesis holds that auto-antibodies may play a role in the biology of schizophrenia. Natural auto-antibodies, preexisting any antigenic stimulation, may also be involved, particularly in the response to neuroleptic drugs.


Sodium, calcium and exocytosis: confessions of calcified scientists.

Stimulated exocytotic secretion from nerve endings is initiated by an increase in intracellular free calcium concentration. We summarize here our latest findings regarding the temporal relationship between depolarization, elevation of [Ca2+]i and exocytosis in single vertebrate neuroendocrine nerve endings. In addition, we present surprising findings for a regulatory role of intracellular Na+ on exocytosis.


Synergistic regulation of cytosolic Ca2+ concentration by somatostatin and alpha 1-adrenergic agonists in mouse astrocytes.

The effects of somatostatin and alpha 1-adrenergic receptor agonists on cytosolic Ca2+ in striatal astrocytes from the embryonic mouse in primary culture have been investigated by microfluorimetry. Methoxamine or somatostatin induced a transitory increase in cytosolic Ca2+, but their combined addition led to a sustained increase in cytosolic Ca2+ which seems to be due to a Ca2+ influx since it was not observed in the absence of external Ca2+. Voltage-independent Ca2+ channels contribute to this process. Indeed, voltage-operated calcium channels are not involved since neither dihydropyridines nor La3+ were effective in suppressing the sustained cytosolic Ca2+ elevation. Moreover, depolarization by 50 mM KCl, which was ineffective alone, suppressed the effect of somatostatin observed in the presence of the alpha 1 agonist, methoxamine. The implication of arachidonic acid in the observed potentiation is suggested by the following observations: 1) arachidonic acid induced a sustained elevation of cytosolic Ca2+ similar to that evoked by the co-application of methoxamine and somatostatin; 2) the addition of ETYA, an inactive and non-metabolizable analogue of arachidonic acid suppressed the calcium plateau produced by the agonists. In addition, direct activation of PKC by an exogeneous diacylglycerol analogue allowed somatostatin alone to evoke a sustained elevation of cytosolic Ca2+. Therefore, methoxamine through the successive activation of PLC and PKC could allow a lipase, probably PLA2, to be stimulated by somatostatin. Since arachidonic acid has already been shown to trigger the opening of K+ channels and the formation of inositol phosphates, somatostatin, through the arachidonic acid-mediated hyperpolarization could increase the Ca2+ driving force and thus improve Ca2+ influx through the inositol phosphate gated channels.


Enkephalin biosynthesis is coupled to secretory activity via transcription of the proenkephalin A gene.

The molecular mechanisms regulating neuropeptide and secretory protein biosynthesis in neuroendocrine cells were examined using the prototype neuropeptide and secretory proteins enkephalin and chromogranin A (CGA). Treatment with the secretogogue nicotine results in the calcium-dependent secretion of enkephalin peptides from bovine chromaffin cells in primary culture and a concomitant increase in enkephalin peptide biosynthesis. Both secretion and biosynthesis are also stimulated by cell depolarization with elevated potassium. Elevation of intracellular cyclic AMP, on the other hand, results in stimulation of enkephalin biosynthesis and long-term, but not acute, secretion of enkephalin peptides. Coupling of enkephalin biosynthesis to calcium influx occurs at the level of transcription of the enkephalin gene. Thus, potassium depolarization causes a calcium-dependent elevation of enkephalin mRNA which is preceded by an increase in the rate of transcription of the enkephalin gene in the chromaffin cell. The accumulation of enkephalin message or peptide by potassium depolarization or treatment with nicotine is prevented by D600 or hexamethonium respectively, added 1 h after addition of nicotine or KCl and following acute release, suggesting that calcium acts as a continuous rather than triggering stimulus for enkephalin biosynthesis. Sequence analysis of the bovine enkephalin promoter identified sequence conservation of three enhancers previously reported in the human gene which are required for regulation of the gene by calcium, cAMP, and phorbol ester in vitro. In contrast to the regulation of the enkephalin system, no increase in either CGA or CGB mRNA or gene transcription attended depolarization-induced secretion from chromaffin cells. Since enkephalin and CGA are co-stored in and co-released from the same secretory vesicles in these cells, the results imply that a surplus of CGA is constitutively synthesized in chromaffin cells such that compensatory up-regulation during changes in the secretory state of the cell, such as occurs for enkephalin, is not required for the secretory proteins.


Comparison of the effect of midazolam or vecuronium on blood pressure and cerebral blood flow velocity in the premature newborn.

The effect of midazolam and vecuronium on mean arterial pressure (MAP) and mean cerebral blood flow velocity (MCBFV) was evaluated in premature infants (birthweight 550-2,560 g; gestational age 26-36 weeks) randomised to receive either 0.1 mg/kg midazolam (n = 7) or 0.05 mg/kg vecuronium (n = 8) intravenously. MAP, by means of an indwelling arterial catheter, and MCBFV, by means of non-invasive pulsed-Doppler of the middle cerebral artery, were measured every 5 min, starting at 10 min prior to until 1 h after drug administration. A transient 25-43% decrease in MCBFV (mean 0.06 m/s) dependent on a 8-23% decrease in blood pressure (mean 9 mm Hg) was noted in all patients within 15 min following administration of midazolam, which returned to baseline values within 1 h. In 2 out of 7 infants, a plasma expander was required. In contrast, vecuronium only decreased the MCBFV in 3 of 8 infants. Thus, a bolus of midazolam transiently decreased blood pressure and MCBFV, and should be used cautiously in sick preterm infants.


The Pf332 gene codes for a megadalton protein of Plasmodium falciparum asexual blood stages.

We characterized the Plasmodium falciparum antigen 332 (Ag332) which is specifically expressed during the asexual intraerythrocytic cycle of the parasite. The corresponding Pf332 gene has been located in the subtelomeric region of chromosome 11. Furthermore, it is present in all strains so far analyzed and shows marked restriction length fragment polymorphism. Partial sequence and restriction endonuclease digestion of cloned fragments revealed that the Pf332 gene is composed of highly degenerated repeats rich in glutamic acid. Mung been nuclease digestion and Northern blot analysis suggested that the Pf332 gene codes for a protein of about 700 kDa. These data were further confirmed by Western blot and immunoprecipitation of parasites extracts with an antiserum raised against a recombinant clone expressing part of the Ag332. Confocal immunofluorescence showed that Ag332 is translocated from the parasite to the surface of infected red blood cells within vesicle-like structures. In addition, Ag332 was detected on the surface of monkey erythrocytes infected with Plasmodium falciparum.


Transmission immunity in malaria: reflections on the underlying immune mechanisms during natural infections and following artificial immunization.

Malaria transmission-blocking immunity has been studied in natural malarial infections in man, during infections in animals and following artificial immunization of animals with sexual stage malaria parasites. Effective immunity, which prevents infectivity of a malarial infection to mosquitoes, has been observed under all of these circumstances. Two general types of effector mechanism have been identified. One is an antibody mediated mechanism which acts against the extracellular sexual stages of the parasite within the midgut of a blood feeding mosquito. The other is a cytokine mediated mechanism which inactivates the gametocytes of the parasites while still in the circulation of the vertebrate host. Both effects have been observed during natural infections and following artificial immunization. The basis of induction of transmission-blocking immunity, including the nature of the memory for such immunity, however, may be very different in different host/parasite systems and during natural infection or following artificial immunization. Following artificial immunization a strong immune memory for transmission blocking immunity has been observed in animal systems. By contrast, following natural infections in man immune memory for transmission blocking immunity has been found to be weak and short lived if it occurs at all. It is suggested that the immunogens which induce natural transmission blocking immunity may be CD4+ independent.


T cell responses to repeat and non-repeat regions of the circumsporozoite protein detected in volunteers immunized with Plasmodium falciparum sporozoites.

The design of a malarial vaccine based on the circumsporozoite (CS) protein, a major surface antigen of the sporozoite stage of the malaria parasite, requires the identification of T and B cell epitopes for inclusion in recombinant or synthetic vaccine candidates. We have investigated the specificity and function of a series of T cell clones, derived from volunteers immunized with Plasmodium falciparum sporozoites, in an effort to identify relevant epitopes in the immune response to the pre-erythrocytic stages of the parasite. CD4+ T cell clones were obtained which specifically recognized a repetitive epitope located in the 5' repeat region of the CS protein. This epitope, when conjugated to the 3' repeat region in a synthetic MAPs construct, induced high titers of antisporozoite antibodies in C57BL mice. A second T cell epitope, which mapped to aa 326-345 of the carboxy terminal, was recognized by lytic, as well as non-lytic, CD4+ T cells derived from the sporozoite-immunized volunteers. The demonstration of CD4+ CTL in the human volunteers, and the recent studies in the rodent model (Renia et al., 1991; Tsuji et al., 1990), suggest that CS-specific CD4+ T cells, in addition to their indirect role as helper cells in the induction of antibody and CD8+ effector cells, may also play a direct role in protection against sporozoite challenge by targeting EEF within the liver.


South American monkeys in the development and testing of malarial vaccines--a review.

South American Aotus and Saimiri monkeys, which are susceptible to infection with human malarias, have been used to develop models for the testing of human malaria vaccines. Studies indicate that blood-stage and sporozoite vaccines can be tested in these monkeys using appropriate strains of parasites.


Molecular biological approaches to the study of vectors in relation to malaria control.

To a large extent, control of malaria vectors relies on the elimination of breeding sites and the application of chemical agents. There are increasing problems associated with the use of synthetic insecticides for vector control, including the evolution of resistance, the high cost of developing and registering new insecticides and an awareness of pollution from insecticide residues. These factors have stimulated interest in the application of molecular biology to the study of mosquito vectors of malaria; focussing primarily on two aspects. First, the improvement of existing control measures through the development of simplified DNA probe systems suitable for identification of vectors of malaria. The development of synthetic, non-radioactive DNA probes suitable for the identification of species in the Anopheles gambiae complex is described with the aim of defining a simplified methodology which is suitable for entomologist in the field. The second aspect to be considered is the development of completely novel strategies through the genetic manipulation of insect vectors of malaria in order to alter their ability to transmit the disease. The major requirements for producing transgenic mosquitoes are outlined together with the progress which has been made to date and discussed in relation to the prospects which this type of approach has for the future control of malaria.


CD4+ lymphocyte involvement in ocular Behçet's disease.

Despite extensive study, the pathogenic mechanisms of Behçet's disease remain uncertain. The ocular inflammation caused by this disease is severe, often causing significant visual loss and, although the nature of the cellular infiltrate has been examined in many of the involved organs, the infiltrating cells in inflamed eyes have not. To investigate the mechanisms involved in perpetuating the ocular inflammation, five enucleated eyes from patients with Behçet's disease were examined by immunohistochemical staining using a panel of monoclonal and polyclonal antibodies. Control eyes from patients with chronic intraocular inflammation from other causes were also examined. Cellular infiltrates were a consistent finding in choroid and periretinal scar tissue, formed almost entirely by mononuclear cells. T lymphocytes were found to predominate (largely the CD4+ subset). B lymphocytes and NK cells were infrequent findings but macrophages were present in significant numbers. No complement or immunoglobulin deposits were found. Infiltrating lymphocytes and macrophages were HLA DR positive. Retinal vascular and retinal pigment epithelium were only occasionally positive. Our findings suggest that cell mediated immunity, rather than immune complex deposition is responsible for the perpetuation of the ocular inflammation in Behçet's disease and that CD4+ T lymphocytes play a central role in this.


Results of therapy for beta-thalassemia major.

During the last 10 years, 92 transfusion-dependent beta-thalassemia patients have been encountered at the National Taiwan University Hospital and Provincial Taoyuan General Hospital. Seventy-seven of them were followed up regularly. Long-term results of conventional therapy in 63 cases and allogeneic bone marrow transplantation (BMT) in 14 cases are reported. The conventional therapy included regular red cell transfusion and desferrioxamine iron chelation therapy. Preliminary results of conventional therapy showed a mortality of 7/63 (11%). Of those who were alive, the morbidity was 56/56 (100%). There was no disease-free-survival (0/56; 0%). BMT was performed after preparatory regimens of busulfan, cyclophosphamide, and/or total body or lymphoid irradiation. Preliminary results of BMT showed a mortality of 5/14 (36%). For those who were alive, the morbidity was 3/9 (33%), and the disease-free-survival rate was 6/9 (67%) during a follow-up period of three to six years. It is concluded that the only way to cure beta-thalassemia major at present is BMT. However, the risks of BMT and donor non-availability make conventional therapy unavoidable. Further study is needed to decrease the risk of BMT and to improve the efficacy of conventional therapy.


Single-breath carbon monoxide diffusing capacity: effect of body size and age in healthy nonsmoking Chinese.

Because of unanswered questions about reference values for single-breath carbon monoxide diffusing capacity (DLCO) in Chinese, standardized DLCO measurements were carried out in a selected sample of 257 healthy nonsmoking Chinese aged 20-70 years. The methods of measurement essentially followed the American Thoracic Society (ATS) recommendations. The measured DLCO was corrected to a standard hemoglobin value. Observed mean values for DLCO were 25.87 +/- 5.64 mL/min/mmHg in men and 21.16 +/- 3.88 mL/min/mmHg in women. Correlations of DLCO indices with anthropometric variables revealed that DLCO was best correlated with age in both sexes (r = -0.71 for men and r = -0.61 for women, p < 0.001). For alveolar volume (VA), the most significant correlation was found with height. For specific diffusing capacity (DLCO/VA), there was a significant negative relationship with age. Reference equations using age and body surface area (BSA) as independent variables for DLCO, VA and DLCO/VA were derived separately for men and women. An analysis of the distribution of residuals was Gaussian with simple linear regressions. Predicted values for DLCO and VA, as estimated in the present study, were much lower than equations derived from Caucasian populations. On the contrary, DLCO/VA values, as predicted by the present set of equations, were comparable to those of Caucasian equations. Therefore, differences in DLCO values between Chinese and Caucasians may be explained by differences in lung volume rather than by ethnic variations in the inherent characteristics of the alveolar capillary membrane. Predicted values for Chinese should be obtained from equations established from this study rather than extrapolated from those of Caucasians. The results of this study will be of value to clinical laboratories dealing with pulmonary function testing for Chinese patients.


Age trends in lung cancer.

To investigate the relationship between the stages of cancer development and the age trends in histologic type found at the time of disease diagnosis, we studied 1,669 patients with histologically proven lung cancer. These patients were examined at the National Taiwan University Hospital using Mantel-Haenszel Chi-square testing to determine a linear trend. These patients were divided into three age groups: group 1 (< 45 years), 141 patients (8%); group 2 (45-64 years), 946 patients (57%); group 3 (65 years or more), 582 patients (35%). The ratio of men to women was 1.4 in group 1, 2.5 in group 2 and 2.3 in group 3. In men, there was a significant trend for the proportion of squamous cell carcinoma to increase from 26% to 42% and that of adenocarcinoma to decrease from 52% to 34% as age increased. In women, an age trend for histologic type was not observed. There was also a significant trend for local-stage squamous cell carcinoma in men to increase from 18% in group 1 to 35% in group 2 and to 42% in group 3. In men, but not in women, local-stage large cell carcinoma increased from 20% in group 1 to 31% in group 2 and to 64% in group 3. However, the age-stage trend for other cell types was not significant in men.(ABSTRACT TRUNCATED AT 250 WORDS)


Clinical manifestations of bronchogenic carcinoma.

A retrospective clinical study was carried out on 227 pathologically proven cases of bronchogenic carcinoma from eastern Taiwan, between October 1986 and March 1990. The ratio of males to females was low (2.15:1). The most common cell type was adenocarcinoma (39.2%), with squamous cell carcinoma (36.1%) being the second most common. Adenocarcinoma contributed to 51.4% of the bronchogenic carcinoma in women and 33.5% in men. History of cigarette smoking was strongly associated with squamous cell carcinoma and small cell carcinoma. The most common symptom was a cough (69%). The majority of small cell carcinoma and squamous cell carcinoma appeared to be of the central type in location while most adenocarcinoma appeared to be of the peripheral type. Bronchoscopic examination was the most valuable method for confirming the diagnosis of bronchogenic carcinoma. Most patients presented late and only 19 cases (8.4%) underwent surgery. Aborigines have a lower risk of developing bronchogenic carcinoma. The clinical manifestations of bronchogenic carcinoma in eastern Taiwan are similar to those found in Taiwan as a whole.


Cytomorphometric and flow cytometric analysis of bladder transitional cell carcinoma using acridine orange fluorochrome: correlation with histopathology and clinical behavior.

Cell material from 79 cases of archival paraffin-embedded tumor specimens of newly diagnosed transitional cell carcinomas of the urinary bladder was studied retrospectively using rapid flow cytofluorometric DNA analysis. The male to female ratio was 62/17. The mean age at diagnosis was 65.3 +/- 10.8 years. Clinical characteristics, including survival, recurrence and progression were closely related to the histopathologic grading and tumor staging. The tumors were classified as diploid (DI = 0.9-1.1) or aneuploid. Total aneuploid occurrence was 46%. The aneuploid frequency for the various tumor grades was 25% for grade 1, 37% for grade 2 and 78% for grade 3. Stages Ta (O) and Tl (A) tumors differed from muscle-invasive tumors (T2-4) in that they had a lower frequency of aneuploid occurrence (34%, 41% vs 50%, 73%, and 75%). Multiple aneuploid stem cell lines had no influence on tumor grade or stage. The DNA ploidy was closely related to the five-year survival rate, the probability of tumor recurrence and progression. On the contrary, the modal nuclear size of the tumor cells had no correlation with histopathology or the clinical characteristics. Bladder tumors of an intermediate grade (grade 2) may be subdivided into two groups with different outcomes on the basis of flow cytometric characteristics. It is concluded that DNA flow cytometry can serve as an additional prognostic parameter for bladder cancer patients in addition to conventional histopathology.


Total cavopulmonary connection for surgical treatment of complex congenital heart disease.

Diversion of vena caval flow directly into the pulmonary circulation--total cavopulmonary connection--has been tried at our hospital for two years as an alternative to the modified Fontan procedure for surgical treatment of complex congenital heart disease other than tricuspid atresia in 26 cases with six operative mortalities. The causes of death were low cardiac output in four, uncontrollable paroxysmal supraventricular tachycardia in one and airway obstruction in one. Except for one late death which occurred three months after surgery due to sepsis, the 19 patients who survived the operation were followed up for four to 27 months (mean 15 months). All of them improved clinically (NYHA Class 1). Graded bicycle exercise tests were performed in five of them at three to 12 months after surgery, and their exercise tolerance was comparable to that of patients with an atriopulmonary connection. In conclusion, total cavopulmonary connection is an acceptable alternative to the modified Fontan operation for surgical treatment of complex congenital heart disease, although longer follow-up is necessary.


Endoscopic approaches in the diagnosis of obstructive jaundice--with special reference to endoscopic retrograde cholangiopancreatography.

Duodenofiberscopy with endoscopic retrograde cholangiopancreatography (ERCP) was performed in 102 patients with obstructive jaundice. Peritoneoscopy and peritoneoscopic cholecystocholangiography were done in patients whose ERCP was inconclusive. The causes of obstructive jaundice were carcinoma of the pancreas in 14 cases, carcinoma of the papilla of Vater in 12 cases, choledocholithiasis in 37 cases, carcinoma of the common bile duct in seven cases, hepatocellular carcinoma (HCC) in seven cases, intrahepatic cholestasis in three cases and miscellaneous causes in eight cases. No final diagnosis was made in 14 patients. The duodenofiberscopic examination with biopsy revealed the cause of obstructive jaundice directly in eight cases, when carcinoma of the pancreas or papilla of Vater extended to the duodenal mucosal surface. In 34 of the 37 patients with choledocholithiasis, ERCP alone was successful in making the diagnosis. Percutaneous transhepatic cholangiography and ERCP were used together to reach a diagnosis in the remaining three patients. We propose a classification for HCC on ERCP which may be useful for the study of icteric type HCC.