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Biomedical subjects

S Venturoli

Publications and source records attributed to S Venturoli.

At least 91 records · Page 5Linked to original sources
PubMed1993

Nested polymerase chain reaction assay for the detection of B19 parvovirus DNA in human immunodeficiency virus patients.

Persistent B19 parvovirus infection has been recognized in immunocompromised patients, often occurring with a low-titer viremia. In this study, nested polymerase chain reaction (PCR) for the detection of B19 parvovirus DNA was carried out on the sera of 49 human immunodeficiency virus (HIV)-1-seropositive patients, negative for the detection of B19 DNA at dot blot hybridization assay and with different values of serum anti-B19 IgM (27 patients proved positive and 22 negative). Of the 49 HIV-seropositive samples tested by nested PCR, seven were positive for the detection of B19 DNA. All seven belonged to the group of subjects seropositive for specific anti-B19 IgM. The study shows that, in the presence of specific B19 IgM, circulating virus may still be present but can be detected only by PCR. In that B19 infection can occur with low-titer viremia in immunocompromised patients, PCR may be the only method for virus detection.

Adult↗
PubMed1993

In situ detection of B19 DNA in bone marrow of immunodeficient patients using a digoxigenin-labelled probe.

An in situ hybridization assay using a digoxigenin-labelled probe was developed to detect B19 DNA in bone marrow erythroid elements of immunodeficient patients with hypoplastic anaemia. A 700 bp Bam HI-Hin dIII fragment of B19 DNA was used to construct the probe by incorporating deoxyuridine triphosphate labelled with digoxigenin. The in situ hybridized B19 DNA probe was visualized by an immunoenzymatic reaction using antidigoxigenin Fab fragments labelled with alkaline phosphatase. Dark blue coloured inclusions at the enzyme site were detected in the nuclei of B19 infected erythroid cells at different stages of cell differentiation. Six out of the nine patients studied showed a positive reaction by in situ hybridization assay. The assay we developed proved highly specific and sensitive and it appears to be a suitable diagnostic test for investigating the possible role of B19 infection as a cause of haematopoietic disorders in immunocompromised hosts.

Anemia, Aplastic↗
PubMed1993

Microplate capture hybridization of amplified parvovirus B19 DNA fragment labelled with digoxigenin.

A capture hybridization technique in microplate has been developed for the identification of polymerase chain reaction (PCR) amplified B19 DNA fragment in clinical specimens. The amplified 104 bp B19 DNA fragment, located in the gene coding for structural proteins, was directly labelled during the amplification reaction by incorporation of digoxigenin-labelled dUTP. The amplified product was then captured by a probe immobilized on microplate wells. The capture hybridization reaction was visualized as an enzyme-linked immunosorbent assay using anti-digoxigenin Fab fragment labelled with peroxidase. Thirty-five serum samples were tested by our capture hybridization assay and the results were in accordance with the results obtained by Southern blot analysis of PCR amplified product. Our microplate capture hybridization assay showed a high sensitivity and reproducibility and appears to be a practical and reliable test for routine screening of B19 parvovirus DNA in clinical specimens.

Base Sequence↗
PubMed1993

Efficient parvovirus B19 DNA purification and molecular cloning.

A simple and efficient method of purification and molecular cloning of Parvovirus B19 DNA directly from small quantities of viremic sera was developed. Purified virions were lysed in annealing conditions, then viral DNA purification in double strand (ds) DNA form was achieved using an affinity DNA binding matrix. Affinity purification yielded a consistently high recovery of viral DNA. Using affinity purified ds viral DNA, we efficiently and stably cloned the complete coding internal unique sequence of B19 DNA. In our cloning strategy AatII and BamHI restriction endonuclease sites were exploited. This permitted cleavage of the 5.0 kbp AatII fragment in two AatII-BamHI fragments which could be efficiently cloned in a directional way in pUC18 plasmid vector. The availability of the two cloned AatII-BamHI fragments thus allowed the construction of a full length clone in a single ligation reaction.

Cloning, Molecular↗
PubMed1993

Symptomatic parvovirus B19 infection of one fetus in a twin pregnancy.

Twin pregnancies complicated by infection due to parvovirus B19 are uncommon. We report a case in which only one fetus developed a symptomatic infection, which presented at first as ascites and pleural effusion; later, meconium peritonitis developed. Hydrops spontaneously resolved, and at birth meconium peritonitis was successfully treated with surgery. However, even with the positive outcome of this pregnancy, a long-term follow-up is needed to exclude damage other than injury to the erythropoietic system.

Adult↗
PubMed1993

Insulin and androgen relationships with abdominal body fat distribution in women with and without hyperandrogenism.

This retrospective study was carried out to investigate, in a large group of hyperandrogenized women with polycystic ovary syndrome (PCOS) and nonhyperandrogenized control women, the interrelationships between sex steroids and indices of body fat distribution. Moreover, we investigated the relationships between these parameters and insulin blood levels, since obese women with abdominal pattern of fat distribution (A-BFD), as well as those with PCOS (either obese and nonobese) are characterized by moderate to severe hyperinsulinemia. A sample of 100 women with PCOS and that of 138 women without clinical signs of hyperandrogenism, who served as a control group, were investigated. The waist to hip circumference ratio (WHR) which was used to define different patterns of fat topography was significantly (p < 0.05) higher in PCOS (0.84 +/- 0.10) than in control women (0.81 +/- 0.08). In both groups, women with WHR values lower than or equal to 0.85 were considered as having a peripheral pattern of body fat distribution (P-BFD) whereas those having WHR values higher than 0.85 had A-BFD. Compared to controls, women with PCOS had higher LH, androgen and estrogen concentrations. In both PCOS and controls there were no differences in sex hormone levels between women with different patterns of fat distribution, except androstenedione, which levels were significantly higher in women with A-BFD than with P-BFD. Women with PCOS showed significantly higher insulin levels than controls. Moreover, in both groups fasting and stimulated insulin were significantly higher in women with A-BFD than in those with P-BFD.(ABSTRACT TRUNCATED AT 250 WORDS)

Abdomen↗
PubMed1993

Changes in brain catecholamine metabolism during bromocriptine treatment in polycystic ovary syndrome.

The role of dopaminomimetic drugs on the brain catecholamine metabolism in the neuroendocrine regulation of the polycystic ovary syndrome (PCO) was investigated. We measured, besides peptide hormones and sex steroids, urinary dopamine (DA), norepinephrine, epinephrine, vanillylmandelic acid, homovanillic acid (HVA), 3,4-dihydroxyphenylacetic acid (DOPAC) and total 3-methoxy-4-hydroxyphenylglycol (MHPG) levels by high-performance liquid chromatography with electrochemical detector in 10 women with PCO before and during long-term bromocriptine (BRC) administration. HVA and DOPAC concentrations were significantly lower (p < 0.001) in PCO patients compared with 12 control subjects in the early follicular phase, whereas MHPG concentrations were significantly higher (p < 0.01) in PCO patients. During BRC administration, HVA, DOPAC and MHPG levels increased significantly (p < 0.01 for HVA and DOPAC, and p < 0.05) for MHPG), prolactin levels dropped markedly (p < 0.01), whereas luteinizing hormone levels did not change (p = NS). These data show (1) a reduced DA activity in PCO which may be normalizable under BRC treatment, but also (2) no major effects of DA metabolism on the inappropriate gonadotropin secretion of the syndrome.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1993

Adeno-pituitary hormones in human hypothalamic hypophysial blood.

An in vivo technique for collecting blood from the pituitary stalk using transphenoidal microsurgery has recently been developed in men with nonfunctioning pituitary disease. To determine the origin of this blood and the direction of the stream, we measured contemporaneously the levels of LH, FSH, PRL, GH, TSH, and ACTH in hypothalamic-hypophysial blood (HHB) and peripheral blood (PB). Eleven patients with nonfunctioning pituitary adenomas entered the study. The surgical procedure used for collecting HHB consisted of periodically aspirating small amounts of blood using a microsuction apparatus, just after tumor removal, kept in the postero-superior corner of the sella turcica at the junction of the diaphragm with the dursum sellae. The data show clearly the existence of a dramatic concentration gap in HHB vs. PB in all adeno-pituitary hormones (P = 0.003). The HHB/PB ratio varied from 50-600 in the different hormones. The secretion of adeno-pituitary hormones in blood drawn at the pituitary stalk level in man was reported for the first time. The dramatic HHB/PB ratio of the hormone levels has been emphasized. The most likely explanation for the markedly elevated hormone concentration gradient between central and peripheral blood was sampling of peri- and/or suprapituitary blood. To consider the origin and direction of the HHB stream, two hypotheses have been further advanced: 1) a retrograde bloodflow from the pituitary, and 2) a central-hypothalamic secretion.

Adenoma↗
PubMed1992

Different syndromes associated with B19 parvovirus viraemia in paediatric patients: report of four cases.

The broad spectrum of clinical manifestations associated with B19 parvovirus often allows the infection to go unrecognized. We tested for the presence of B19 parvovirus and the specific serological response in serum from hospitalized patients submitted for viral investigations without any specific indications for B19 parvovirus. We diagnosed human parvovirus B19 infection in four paediatric patients showing different clinical manifestations. The patients, aged between 5 and 8 years, were admitted to hospital for: (1) petechial rash; (2) mononucleosis-like syndrome; (3) neurological syndrome; and (4) respiratory disease (in an immunodeficient patient).

Child↗
PubMed1992

Detection of CMV DNA in clinical samples of AIDS patients by chemiluminescence hybridization.

A sensitive chemiluminescence dot-blot hybridization assay for the detection of CMV DNA in clinical samples of AIDS patients is described. In the chemiluminescence hybridization assay, digoxigenin-labelled CMV DNA probes were used and when hybridized they were detected by anti-digoxigenin Fab fragments conjugated with alkaline phosphatase. Adamantyl 1,2-dioxetane phenyl phosphate was used as the chemiluminescent substrate. The results were recorded by instant photographic films. The results obtained with the chemiluminescence hybridization assay were compared with the results obtained by hybridization with colourimetric detection. The chemiluminescent assay proved specific, sensitive and reliable and thus can be used as a valuable routine diagnostic test for the detection of CMV DNA in clinical samples.

Acquired Immunodeficiency Syndrome↗
PubMed1992

Double in situ hybridization for detection of Herpes simplex virus and cytomegalovirus DNA using non-radioactive probes.

We describe a double in situ hybridization assay for the simultaneous detection of Herpes simplex virus (HSV) and cytomegalovirus (CMV) DNA in infected cell cultures using non-radioactive-labeled probes. This work used a biotinylated HSV DNA probe, which can be revealed by an avidin-biotin-peroxidase complex and a digoxigenin-labeled CMV DNA probe, visualized by anti-digoxigenin F(ab) fragments conjugated with alkaline phosphatase. Light microscopy visualization was achieved by the contrasting colors of appropriate peroxidase and alkaline phosphatase reaction products (red and dark blue, respectively). The time required to perform the double hybridization assay was about 3 hr. This double hybridization assay proved to be sensitive, specific, and provided good resolving power.

Acquired Immunodeficiency Syndrome↗
PubMed1992

Longitudinal evaluation of the different gonadotropin pulsatile patterns in anovulatory cycles of young girls.

We studied 13 adolescents (mean gynecological age 29.2 +/- 14.1 months) with anovulatory cycles and 7 women with ovulatory cycles (mean gynecological age 33.1 +/- 15.3 months) as a control group. Adolescents with anovulatory cycles were grouped on the basis of mean plasma LH values: group 1 (n = 7) with high LH values, and group 2 (n = 6) with normal LH values. In all women plasma gonadotropin concentrations were measured at 10-min intervals for 8 h on day 4 of the cycle. Pulsatile gonadotropin secretion was also studied in each subject a second time 40 months later, to establish the outcome of the different pulsatile patterns. Group 1 had more frequent and greater LH pulses than the other two groups (which were similar) and had the highest plasma 17 beta estradiol, testosterone, androstenedione, and 17 hydroxyprogesterone concentrations. Longitudinal control showed that: in group 1, three subjects out of seven acquired ovulatory cycles and there was a fall in mean LH plasma levels (30 +/- 5 vs. 9 +/- 4 IU/L; P less than 0.01), number of pulses (8.3 +/- 1.5 vs. 5 +/- 0; P less than 0.025), mean amplitude (13 +/- 3 vs. 5 +/- 2 IU/L; P less than 0.02) and an increase in interpulse interval (56 +/- 10 vs. 91 +/- 6 min; P less than 0.01). In four subjects anovulatory cycles persisted and the LH pulsatile profile remained unchanged. In group 2, five subjects out of six acquired ovulatory cycles, but there were no significant changes in the number of pulses (6 +/- 1 vs. 6 +/- 2; P = NS), interpulse interval (97 +/- 30 vs. 85 +/- 30 min; P = NS), or amplitude (5 +/- 2 vs. 4 +/- 2 IU/L; P = NS). The results indicate that: 1) anovulatory young women with early normal plasma LH values have an adequate GnRh pulsatile pattern which will easily lead to ovulation; 2) anovulatory young women with high LH plasma values may have a reproductive system blocked in a pathological condition, similar to that observed in polycystic ovary syndrome; 3) only few subjects with high plasma LH values are able to achieve ovulation and normalize LH pulsatile pattern as a consequence of a new mode of GnRh release.

Adolescent↗
PubMed1991

Chemiluminescence dot blot hybridization assay for detection of B19 parvovirus DNA in human sera.

A chemiluminescence dot blot hybridization assay was used for the detection of B19 parvovirus DNA in human sera by using digoxigenin-labeled probes. The probes were revealed immunoenzymatically by use of anti-digoxigenin Fab fragments conjugated with alkaline phosphatase. The chemiluminescence signal was obtained by reacting the labeled probe-target complex with an enzyme-triggerable dioxetane substrate. The emitted photons were detected with instant photographic films. In the search for B19 parvovirus DNA, 2,808 serum samples were analyzed.

DNA Probes↗
PubMed1991

Evidence for a pathological reduction in brain dopamine metabolism in idiopathic hyperprolactinemia.

The role of brain catecholamine activity in the neuroendocrine regulation of the dopamine-PRL system in idiopathic hyperprolactinemia was investigated by high-performance liquid chromatography with electrochemical detector. We measured urinary dopamine, norepinephrine, epinephrine, vanillylmandelic acid, homovanillic acid, 3,4-dihydroxyphenylacetic acid and total 3-methoxy-4-hydroxyphenylglycol levels in 12 women with idiopathic hyperprolactinemia before and during either peripheral dopa-decarboxylase blockade, by carbidopa, or dopamine beta-hydroxylase blockade, by disulfiram. Homovanillic acid and 3,4-dihydroxyphenylacetic acid concentrations were significantly lower (p less than 0.001 and p less than 0.005, respectively) in patients with idiopathic hyperprolactinemia compared with those in 12 control subjects in the early follicular phase, whereas they were similar to those in the control subjects in the pre-ovulatory phase. Dopamine, norepinephrine, epinephrine, vanillylmandelic acid and 3-methoxy-4-hydroxyphenylglycol concentrations were similar to those of the control subjects in both phases of the cycle. During carbidopa administration the levels of all urinary catecholamines and metabolites were unchanged, except that of dopamine which dropped remarkably (p less than 0.001). During disulfiram administration dopamine, homovanillic acid and 3,4-dihydroxyphenylacetic acid concentrations increased (p less than 0.05, p less than 0.001 and p less than 0.005, respectively) and those of norepinephrine, vanillylmandelic acid and 3-methoxy-4-hydroxyphenylglycol decreased (p less than 0.05, p less than 0.001 and p less than 0.005, respectively), whereas epinephrine levels remained unaltered. These data support the existence of a quantitatively reduced brain dopamine activity in idiopathic hyperprolactinemia.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1990

Rapid screening for B19 parvovirus DNA in clinical specimens with a digoxigenin-labeled DNA hybridization probe.

A rapid dot blot hybridization assay for the detection of B19 parvovirus DNA in human sera was developed. Small portions of four serum samples were mixed, filtered onto a nylon membrane, and hybridized with a digoxigenin-labeled DNA probe; for each membrane, 380 serum samples could be tested. When a dot was positive by the hybridization assay, the four serum samples dotted together were separately tested to identify the sample positive for B19 DNA. A total of 10,150 serum samples submitted for viral serological and laboratory investigation with no specific requests for B19 testing were analyzed. Nine serum samples were positive for B19 DNA by dot blot hybridization assay, and the results were confirmed by electron microscopy. This method has proven to be reliable, economical in terms of time and costs, and useful for large-scale screening of clinical specimens, both for diagnostic work and for a source of antigen.

DNA Probes↗
PubMed1990

Rapid detection of cytomegalovirus DNA in urine samples with a dot blot hybridization immunoenzymatic assay.

A dot blot hybridization immunoenzymatic assay for the rapid detection of cytomegalovirus DNA in urine samples was developed by using a digoxigenin-labeled probe which was immunoenzymatically visualized by antidigoxigenin Fab fragments labeled with alkaline phosphatase. A total of 516 urine samples from different groups of subjects were analyzed, and the hybridization assay was able to yield results within 24 h. The results obtained were compared with results for detection of cytomegalovirus antigens in infected cell cultures.

Antigens, Viral↗
PubMed1990

Ketoconazole therapy for women with acne and/or hirsutism.

The effects of ketoconazole, a synthetic imidazole derivate, were evaluated in 42 women affected by acne (17 cases) and/or hirsutism (36 cases) treated with 400 mg/day for 3-6 months. Androstenedione, total and free testosterone, 5 alpha dihydrotestosterone and dehydroepiandrosterone levels progressively dropped during treatment while 17 alpha hydroxyprogesterone, estradiol, ACTH, cortisol, LH and FSH levels increased. Dehydroepiandrosterone sulfate decreased only towards the end of treatment, while estrone, sex hormone binding globulin, and PRL remained unchanged. Daily mean +/- SD rate of hair growth, measured by a special image analysis processor, decreased within 3 months of therapy from 0.258 +/- 0.058 to 0.184 +/- 0.039 mm/day (P less than 0.02) and mean +/- SD hair diameter from 0.123 +/- 0.015 to 0.110 +/- 0.013 mm (P less than 0.05) together with decreasing hormone levels. The therapeutic effects of ketoconazole on hirsutism was evident at 6 months in only 14 subjects, while no significant change in hirsutism score was recorded in 22 women who failed to complete the therapy. Acne improved in all cases. Several side effects and complications arose during treatment, such as headache, nausea, loss of scalp hair, hepatitis, and biochemical changes. Even though ketoconazole improves hyperandrogenism, only selected patients are eligible for treatment as scrupulous monitoring is required.

Acne Vulgaris↗