Organization of telomeric and sub-telomeric regions of chromosomes from the protozoan parasite Trypanosoma cruzi.

We present here a characterization of the telomeric and subtelomeric regions of Trypanosoma cruzi chromosomes, using three types of recombinants: cosmids from a genomic library, clones obtained by a vector-adaptor protocol, and a recombinant fragment cloned by a Bal31 trimming protocol. The last nine nucleotides of the T. cruzi overhang are 5'-GGGTTAGGG-3', and there are from 9 to 50 copies of the hexameric repeat 5'-TTAGGG-3', followed by a 189-bp junction sequence common to all recombinants.

Evaluation of recombinant antigens for serodiagnosis of Chagas' disease in South and Central America.

The commercially available diagnostic tests for Chagas' disease employ whole extracts or semipurified fractions of Trypanosoma cruzi epimastigotes. Considerable variation in the reproducibility and reliability of these tests has been reported by different research laboratories, mainly due to cross-reactivity with other pathogens and standardization of the reagents. The use of recombinant antigens for the serodiagnosis of Chagas' disease is recommended to increase the sensitivity and specificity of serological tests.

Omeprazole and ranitidine in long-term treatment of duodenal ulcer: a double-blind comparison of length of time in remission.

In most patients duodenal ulcer is a chronic relapsing disease. If no active maintenance treatment or eradication therapy is given after healing, around 70-100% of patients have a relapse during the first year. We conducted a double-blind multicenter study in 472 patients with duodenal ulcer.

Polymorphonuclear phagocytosis and killing in workers occupationally exposed to hexachlorobenzene.

Phagocytosis and intracellular killing of Candida albicans and Candida pseudotropicalis by neutrophils from 66 workers exposed to chlorinated compounds were studied. Phagocytosis with both antigens was normal in all the workers studied. However, lytic activity of the neutrophils in the presence of both antigens, C.

Mapping of B cell epitopes in an immunodominant antigen of Trypanosoma cruzi using fusions to the Escherichia coli LamB protein.

The JL8 protein antigen from Trypanosoma cruzi, a dominant immunogen in man, has been characterized as containing tandem amino acid repeats. Here, we describe the use of the LamB protein of Escherichia coli as a carrier of JL8 derived sequences in order to map the immunodominant B cell epitopes in this antigen. Five different sequences of JL8 were inserted in the LamB protein and the JL8-LamB fusion proteins were tested by ELISA with human chronic chagasic sera.

Imidazoline receptors of the paraventricular nucleus on the pressor response induced by stimulation of the subfornical organ.

In the present experiments we investigated a possible involvement of imidazoline receptors of the paraventricular nucleus (PVN) of the hypothalamus on the pressor effects of the angiotensin II (ANG II) injected into the subfornical organ (SFO), in male Holtzman rats (250-300 g) with a cannula implanted into the third ventricle (3rdV), PVN and SFO. At first we tested the participation of alpha 2 and imidazoline agonist and antagonist compounds on the pressor effect of ANG II injected into the 3rdV. Based on the results we may conclude that clonidine associated with rilmenidine was able to block the hypertensive response to ANG II.

The Trypanosoma cruzi genome project: nuclear karyotype and gene mapping of clone CL Brener.

By using improved pulsed field gel electrophoresis conditions, the molecular karyotype of the reference clone CL Brener selected for Trypanosoma cruzi genome project was established. A total of 20 uniform chromosomal bands ranging in size from 0.45 to 3.

Parasite genome projects and the Trypanosoma cruzi genome initiative.

Since the start of the human genome project, a great number of genome projects on other "model" organism have been initiated, some of them already completed. Several initiatives have also been started on parasite genomes, mainly through support from WHO/TDR, involving North-South and South-South collaborations, and great hopes are vested in that these initiatives will lead to new tools for disease control and prevention, as well as to the establishment of genomic research technology in developing countries. The Trypanosoma cruzi genome project, using the clone CL-Brener as starting point, has made considerable progress through the concerted action of more than 20 laboratories, most of them in the South.

Towards the physical map of the Trypanosoma cruzi nuclear genome: construction of YAC and BAC libraries of the reference clone T. cruzi CL-Brener.

Strategies to construct the physical map of the Trypanosoma cruzi nuclear genome have to capitalize on three main advantages of the parasite genome, namely (a) its small size, (b) the fact that all chromosomes can be defined, and many of them can be isolated by pulse field gel electrophoresis, and (c) the fact that simple Southern blots of electrophoretic karyotypes can be used to map sequence tagged sites and expressed sequence tags to chromosomal bands. A major drawback to cope with is the complexity of T. cruzi genetics, that hinders the construction of a comprehensive genetic map.

Electrophoretic karyotypes and genome sizing of the pathogenic fungus Paracoccidioides brasiliensis.

Here we present the karyotype analysis and genome sizing of Paracoccidioides brasiliensis, a pathogen refractory to conventional genetic analysis. We have established pulsed-field gel electrophoresis (PFGE) conditions to resolve the high-molecular-weight chromosomal bands of two clinical isolates of P. brasiliensis.

Characterization of an interspersed repetitive DNA element in the genome of Trypanosoma cruzi.

We report the molecular characterization of a middle repetitive DNA sequence, named C6, isolated from the Trypanosoma cruzi genome. C6 appears to be a composite repeated element since 3 subregions may be defined within it on the basis of sequence similarities with other T. cruzi genomic sequences.

Trypanosoma cruzi genome project: biological characteristics and molecular typing of clone CL Brener.

Clone CL Brener is the reference organism used in the Trypanosoma cruzi Genome Project. CL Brener was obtained by cloning procedures from bloodstream trypomastigotes isolated from mice infected with the CL strain. The doubling time of CL Brener epimastigotes cultured at 28 degrees C in liver infusion-tryptose (LIT) medium is 58 +/- 13 h.

Ventromedial hypothalamus lesions increase the dipsogenic responses and reduce the pressor responses to median preoptic area activation.

In this study, we investigated the participation of adrenergic receptors of the median preoptic area (MnPO) and the participation of ventromedial hypothalamus (VMH) in angiotensin II-(ANG II)-induced water intake and pressor responses. Male rats with sham or electrolytic VMH lesions and a stainless steel cannula implanted into the MnPO were used. Noradrenaline, clonidine (an alpha2-adrenergic receptor agonist), or phenylephrine (an alpha1-adrenergic receptor agonist) injected into the MnPO of sham-lesioned rats reduced water ingestion induced by ANG II injected into the same area.

Cloning and characterization of a gene encoding a novel immunodominant antigen of Trypanosoma cruzi.

A Trypanosoma cruzi genomic expression library was screened with a pool of sera obtained from chronic chagasic patients. The recombinant antigen (Tc40) isolated from this library reacted with a large number of serum samples of chronic chagasic patients, suggesting that the presence of anti-Tc40 antibodies may be specifically associated to Chagas' disease. The full-length sequence of the Tc40 gene was determined after isolation of genomic and cDNA clones.

Functional evidence that the central renin-angiotensin system plays a role in the pressor response induced by central injection of carbachol.

We investigated the effects of losartan, an AT1-receptor blocker, and ramipril, a converting enzyme inhibitor, on the pressor response induced by angiotensin II (ANG II) and carbachol (a cholinergic receptor agonist). Male Holtzman rats (250-300 g) with a stainless steel cannula implanted into the lateral ventricle (LV) were used. The injection of losartan (50 nmol/1 microliter) into the LV blocked the pressor response induced by ANG II (12 ng/1 microliter) and carbachol (2 nmol/1 microliter).

Nasal chondroma: a case report and review of the literature.

Although rare tumors, chondromas will on occasion be encountered by the otolaryngologist in his routine daily practice. The authors describe a nasal myxochondroma in an 8-year-old child, which was removed satisfactorily surgically, with no signs of recurrence even after 4 years of follow-up. Because chondromas may also present as nasal polyps, the knowledge of cartilaginous tumors in the nose plays a pivotal role for a better approach to these patients.

The needs of patients with cancer and their caregivers in rural areas.

Purpose/objectives: To describe physical and psychological needs, rank their importance, and identify needs that were not met of patients with cancer and their caregivers living in rural settings.

Design: Exploratory descriptive.

Setting: Rural Vermont.

Impact of nausea/vomiting on quality of life as a visual analogue scale-derived utility score.

Pharmacoeconomic analysis is often based upon incremental cost per increase in survival (cost-effectiveness). Using this definition supportive care measures, which increase quality but not quantity of life, generate a zero denominator and cannot be directly compared with other components of health care cost. Cost-utility analysis, which measures incremental cost per increase in quality-adjusted life-years (QALY), where QALY = utility score x time at risk, addresses this problem, since successful supportive intervention increases the utility score and thus provides a finite denominator in QALY even when absolute survival is unchanged.

Identification of a domain of Trypanosoma cruzi metacyclic trypomastigote surface molecule gp82 required for attachment and invasion of mammalian cells.

Recombinant proteins and synthetic peptides representing various sequences of gp82, a surface glycoprotein of Trypanosoma cruzi metacyclic trypomastigotes implicated in mammalian cell invasion, were used in this study aiming at the identification of the domain(s) of this molecule required for interaction with target cells. Invasion of cultured HeLa cells by metacyclic trypomastigotes was inhibited by about 80% in the presence of native gp82 or the corresponding recombinant construct J18. Inhibition by recombinant proteins J18a and J18b, containing respectively the N-terminal and the C-terminal portions of gp82, was on the order of 30% and 65%.

Role of the alpha 1-, and alpha 2- and beta-adrenoceptors of the median preoptic area on the water intake, renal excretion, and arterial pressure induced by ANG II.

The present experiments were conducted to investigate the role of the alpha 1-, alpha 2- and beta-adrenergic receptors of the median preoptic area (MnPO) on the water intake and urinary electrolyte excretion, elicited by central injections of angiotensin II (ANG II). Prazosin (an alpha 1-adrenergic receptor antagonist) and yohimbine (an alpha 2-adrenergic receptor antagonist) antagonized the water ingestion, Na+, K+, and urine excretion induced by ANG II. Administration of propranolol, a beta-adrenergic receptor antagonist increased the Na+, K+, and urine excretion induced by ANG II.

Inhibitory effect of DUP-753 on the drinking responses of rats to central administration of noradrenaline and angiotensin II and to dehydration.

We investigated the effect of losartan (DUP-753) on the dipsogenic responses produced by intracerebroventricular (icv) injection of noradrenaline (40 nmol/microliters) and angiotensin II (ANG II) (2 ng/microliters) in male Holtzman rats weighing 250-300 g. The effect of DUP-753 was also studied in animals submitted to water deprivation for 30 h. After control injections of isotonic saline (0.

Cloning, characterization, and epitope expression of the major diagnostic antigen of Paracoccidioides brasiliensis.

The 43,000-Da glycoprotein (gp43) of Paracoccidioides brasiliensis is an immunodominant antigen for antibody-dependent and immune cellular responses in patients with paracoccidioidomycosis. In order to identify the peptide epitopes involved in the immunological reactivities of the gp43 and to obtain highly specific recombinant molecules for diagnosis of the infection, genomic and cDNA clones representing the entire coding region of the antigen were sequenced. The gp43 open reading frame was found in a 1,329-base pair fragment with 2 exons interrupted by an intron of 78 nucleotides.

The role of angiotensin AT1 receptors in the diuretic, natriuretic, kaliuretic and blood pressure responses induced by angiotensin II activation of the median preoptic nucleus in conscious rats.

We determined the effects of two classical angiotensin II (ANG II) antagonists, [Sar1, Ala8]-ANG II and [Sar1, Thr8]-ANG II, and losartan (a nonpeptide and selective antagonist for the AT1 angiotensin receptors) on diuresis, natriuresis, kaliuresis and arterial blood pressure induced by ANG II administration into the median preoptic nucleus (MnPO) of male Holtzman rats weighing 250-300 g. Urine was collected in rats submitted to a water load (5% body weight) 1 h later. The volume of the drug solutions injected was 0.

Progesterone administration to ovariectomized rats reduces water and salt intake induced by central administration of angiotensin II.

We tested the effects of estradiol, progesterone and testosterone on water and salt intake induced by angiotensin II (ANG II) injected into the third ventricle of female Holtzman rats weighing 250-300 g. The water and salt ingestion observed after 120 min in the control experiments (injection of 0.5 microliter of 0.