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Biomedical subjects

J Benitez

Publications and source records attributed to J Benitez.

88 records · Page 5Linked to original sources
PubMed1986

Cytogenetic studies in 18 patients with secondary blood disorders.

Cytogenetic studies were carried out in 18 patients with secondary blood diseases; 15 patients had a history of prior malignancy, two had been professionally exposed to carcinogenic agents, and one patient had been treated with immunodepressors. The interval between initial therapy and secondary disease ranged from 13 to 123 months, with a mean of 57.8 months; the mean survival time from the diagnosis of secondary disease was 6 months. Cytogenetic abnormalities were present in 83% of cases, with a trend to hypodiploidy in 90%. The most often involved chromosomes were #5, #7, and 3p. A correlation between the cytogenetic abnormalities and etiologic factors has been analyzed; data from the present series and from the literature suggest a correlation between chromosome #7 and chemical agents, and chromosomes #11, #12, and #17 and physical agents.

Acute Disease↗
PubMed1986

Clinical pharmacological evaluation of an assay kit for intoxications with tricyclic antidepressants.

The performance of an enzyme immunoassay kit (EMIT) to diagnose intoxications with tricyclic antidepressants was compared with a high performance liquid chromatography (HPLC) technique in vitro and in vivo. The cut-off reference solution contained in the kit of nominally 1,140 nM nortriptyline varied from 1,250 to 1,600 nM. In vitro addition of antidepressants gave positive results (change in absorbance above the cut-off value) of approximately 1,100 nM for amitriptyline, imipramine, and desmethylimipramine and approximately 1,600 nM for clomipramine and desmethylclomipramine. In contrast, high concentrations of the tetracyclic antidepressant maprotiline (7,000 nM) and the bicyclic zimeldine (2,000 nM) gave negative results. False positive results were obtained with high concentrations of thioridazine (4,000 nM), chlorpromazine (300 nM), and alimemazine (trimeprazine) (5,000 nM). Of 51 patient samples, five gave readings above the cut-off value, consistent with a tricyclic antidepressant intoxication, but two of these were false positives as compared with the specific HPLC analysis. However, no false negative results were obtained with the EMIT. In conclusion, the EMIT kit is likely to detect intoxications with tricyclic antidepressants but miss intoxications with nontricyclic antidepressants. For a screening method, this is a serious drawback, since maprotiline and zimeldine together make up approximately 25% of the total of antidepressants used in Sweden. Users of the kit must also be aware that certain phenothiazines in high therapeutic doses or in intoxication cases could interfere with this test and might lead to the false diagnosis of intoxication with tricyclic antidepressants.

Antidepressive Agents, Tricyclic↗
PubMed1985

Plasma concentrations of nortriptyline and its 10-hydroxy metabolite in depressed patients--relationship to the debrisoquine hydroxylation metabolic ratio.

In 20 depressed patients treated with nortriptyline (NT) there was a significant relationship between the plasma concentration of NT and the debrisoquine metabolic ratio (rs = 0.77; P less than 0.01). (The debrisoquine test was performed after stopping NT treatment). This is in agreement with the hypothesis that the hydroxylations of NT and debrisoquine are mediated by similar enzymatic mechanisms. In contrast there was no significant relationship between the debrisoquine metabolic ratio and the plasma concentrations of the active metabolite 10-hydroxy-nortriptyline. In 11 of the patients the debrisoquine metabolic ratio was significantly higher during than after NT treatment. This may be due to an inhibition of the debrisoquine hydroxylation by NT.

Debrisoquin↗
PubMed1984

Two fertile Turner women in a family.

Two fertile women, mother and daughter, both presenting sex chromosomal mosaicism (45,X/46,XX/47,XXX and 45,X/46,Xr(X] are reported. The mechanisms through which a Turner women can eventually be fertile are discussed.

Abortion, Spontaneous↗
PubMed1983

Serial cytogenetic study of a human glioma cell line.

Chromosome studies were performed on a human glioma cell line. Nineteen passages were studied, and a heterogeneous chromosome complement with variable modal numbers was found. The main range varied from tetraploidy to triploidy. The presence of identical markers (9p-, 11p+, an increase in the copies of chromosome No. 7) in different passages suggests a clonal evolution.

Brain Neoplasms↗
PubMed1982

Chromosome banding patterns in patients with chronic myelocytic leukemia.

One hundred and nine patients with Ph1-positive chronic myelocytic leukemia were cytogenetically studied with banding methods. Seventy-eight patients were studied in the chronic phase and 39 patients in the blastic phase. The standard translocation was present in 107 cases. Two patients showed complex translocations involving chromosomes No. 6, 9, 22, 11 and No. 9, 22, 11, respectively. Ph1-negative cells were detected in 8 cases (7%). Chromosome aberrations in addition to the Ph1 chromosome were observed in 6 cases (8%) during the chronic phase. The karyotypic findings during the blastic phase were similar to those reported in the past [trisomy 8, iso(17q), and a second Ph1]. The significance of Ph1-negative cells, the geographic heterogeneity of the chromosomal aberrations, the effect of chemotherapy on the appearance of new clones, and the importance of the materials and methods used for the comparison of cytogenetic patterns at different laboratories are discussed.

Chromosome Aberrations↗
PubMed1981

Effect of pentobarbital on the reactivity of isolated human cerebral arteries.

The authors have analyzed the effect of pentobarbital (10(-5) M to 10(-3) M) on the contractile activity of isolated human cerebral arteries. Pentobarbital was found to inhibit both the spontaneous mechanical activity and the basal tone of these vessels. Relaxation induced by this drug was dose-dependent, and was more marked when the arterial tone was previously increased with noradrenalin, potassium chloride, or 5-hydroxytryptamine. In addition, pentobarbital inhibits, in a dose-dependent manner, the contractions elicited by these vasoconstrictor agents. The present findings indicate that barbiturates decrease cerebrovascular reactivity, and disagree with the hypothesis that these drugs reduce raised intracranial pressure by means of exerting a direct constrictive effect on the cerebral arteries.

Cerebral Arteries↗
PubMed1980

Autopsies on two native American Mummies.

An interdisciplinary team performed autopsies on an adult male and an infant male mummy from the American Southwest. Cause of death has not been determined for the infant. The presence of an unhealed skull fracture associated with an apparent hematoma in the adult male is suggestive of trauma as the cause of death in the adult. Evidence of disease is minimal. Analysis of powder thought to be dried blood from the thoracic cavity of the adult suggests the presence of human IgG. The instability of this protein may indicate the presence of proteolytic activity by enzymes that degrade immunoglobulins upon rehydration. The possibility of enzymatic degradation of proteins will be an important factor in future studies of such immunoglobulins in mummy remains and also indicates the importance of maintaining the desiccated condition of mummy tissues.

Adult↗
PubMedDate not supplied

Secretion and glycosylation of Clostridium thermocellum endoglucanase A encoded by the celA gene in Saccharomyces cerevisiae.

The Clostridium thermocellum celA gene encoding endoglucanase A is expressed in Saccharomyces cerevisiae but the enzyme produced from the native celA gene is not secreted. After removal of the bacterial signal peptide-coding sequence, the gene was fused to the promoter and prepro segment of the S. cerevisiae MF alpha 1 gene. This construction directs secretion of active endoglucanase A into the culture medium when introduced in yeast on either replicating or integrating vectors. Secretion of endoglucanase A required growth of transformants on rich medium. The secreted enzyme is a 97,000 Da glycoprotein containing about half of its molecular weight as carbohydrate. This new gene fusion could facilitate further research on protein secretion in yeast by using a cellulase as a marker enzyme.

Blotting, Southern↗
PubMedDate not supplied

[Obstructive uropathy in genital prolapse].

Two cases of genitourinary prolapse are presented, with a severe high obstructive uropathy complicated with lithiasis and infectious picture. Both cases were elderly patients and had had this problem for many years. They had received no urological or gynaecological examination that could have prevented later complications. As presentation frequency of this pathology is scarce, which undoubtedly is an index of health care, we have reviewed the existing literature to confirm the few descriptions currently reported. Incidence, different etiopathogenic theories explaining this picture, distinctive radiological data and treatment are analyzed.

Aged↗
PubMedDate not supplied

[Ultrasonic diagnosis of prostatic adenocarcinoma. Prospective study of a sample of 159 patients].

We studied the value of transrectal echography as the diagnostic means of prostate pathology. We carried out a prospective analysis of a sample of 159 patients, on whom we have anatomopathological documentation which we use as the reliability control for the clinical exploration by means of rectal touch and ultrasonography with transrectal transducer. We have obtained 137 prostate fibromuscular hyperplasias, 3 inflammatory pathologies and 19 adenocarcinomas. A 100% sensitivity in the echographic diagnosis of prostate adenocarcinoma was achieved for this sample.

Adenocarcinoma↗