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Biomedical subjects

L Bruno

Publications and source records attributed to L Bruno.

At least 37 records · Page 2Linked to original sources
PubMed2000

[Psychologic consequences of a case of aortic perforation during an intervention of laparoscopic surgery].

Although rare, the severe complications inherent in the laparoscopic technique can be physically devastating, whereas from a psychological point of view they may be very traumatic because they are perceived by the patient as unexpected and totally out of proportion compared to the perceived expectation of risk prior to surgery. The possible psychological consequences of a case of aortic perforation with cardiac arrest were evaluated using the Rorschach test in a patient who had undergone exploratory laparoscopy for secondary amenorrhea. An analysis of the test did not show psychotraumatic data attributable with certainty to this experience.

Adult↗
PubMed1999

Threshold of pre-T-cell-receptor surface expression is associated with alphabeta T-cell lineage commitment.

BACKGROUND: The development of immature thymocytes is regulated by the pre-T-cell receptor (pre-TCR). The pre-TCR is involved in several developmental processes including rescuing cells from programmed cell death, allelic exclusion and alphabeta versus gammadelta T-cell lineage commitment. A major issue is how the pre-TCR functions to integrate these processes in developing thymocytes. RESULTS: We have used a sensitive immunofluorescence technique to reveal the surface-expression profile of the pre-TCR on immature thymocyte subsets. We show that early pre-T cells (CD25(+)CD44(-)) can be subdivided on the basis of the level of surface pre-TCR expression. Detectable surface pre-TCR expression identified a rapidly cycling population of early pre-T cells which had successfully undergone beta-selection and been rescued from programmed cell death. Late pre-T cells (CD25(-)CD44(-)), which had traversed the beta-selection checkpoint, expressed surprisingly heterogeneous surface levels of the pre-TCR: high levels of surface pre-TCR expression were associated with commitment to the alphabeta T-cell lineage, whereas late pre-T cells with lower levels of surface pre-TCR could develop along both the alphabeta or gammadelta T-cell lineages. CONCLUSIONS: These data demonstrate that the surface expression of the pre-TCR can be used to reveal newly identified stages of T-cell development and to provide insights into alphabeta T-cell lineage commitment. They show that, although pre-TCR expression does not act as a developmental switch per se, its level of surface expression on late pre-T cells predicts their developmental potential.

Animals↗
PubMed1999

Screening for gestational diabetes in Sicily.

OBJECTIVE: To establish the prevalence of gestational diabetes in a universally screened population living in Messina, Sicily, as the first step in evaluating the cost: benefit ratio of screening for carbohydrate intolerance in pregnancy. STUDY DESIGN: Between October 1989 and March 1995, 1,000 pregnant women underwent screening for gestational diabetes with a 50-g, one-hour glucose challenge test. All the risk factors were registered. RESULTS: Two hundred sixty subjects had a value of > or = 135 mg/dL and underwent a full three-hour oral glucose tolerance test. Of them, 46 (4.6%) met the Carpenter-Coustan diagnostic criteria for gestational diabetes. CONCLUSION: The apparent incidence of gestational diabetes (1.2%) prior to screening was only 25% of the incidence determined with the protocol of universal screening (4.6%). If we assume that timely diagnosis and treatment of gestational diabetes provides an important opportunity to improve obstetric outcome and reduce perinatal morbidity, and since women with gestational diabetes are at increased risk of developing diabetes later, the knowledge that the true prevalence is almost four times that previously reported is a determinant of a future evaluation of the cost:benefit ratio of screening universally for gestational diabetes.

Adult↗
PubMed1999

Glucose tolerance and insulin secretion in pregnancy.

The authors have studied the behaviour of plasma glucose, insulinaemia and insulin-glucose ratio in 2 groups of pregnant women with BMI values > or = or <26, respectively. Each group was divided into 3 subgroups on the basis of an oral glucose tolerance test (OGTT) response: GIGT (gestational impaired glucose tolerance), GD (gestational diabetes), and C (normal controls). Data from non-obese pregnant women demonstrate that both basal and OGTT-stimulated glucose levels were significantly different in all subgroups. The total insulin amount in the GIGT and GD subgroups is quite similar to or greater than the controls, but with a significant reduction of the insulin-glucose ratio. In GD also an absolute deficiency of insulin rise at 30 min during the glucose load, as in subjects with Type 2 diabetes mellitus (T2DM), was observed. The behaviour of these parameters in obese pregnant women seems to be similar, even though with some significant differences: in these subjects, there is a less clear-cut differentiation among all subgroups, and the appearance of gestational diabetes is not accompanied by a significant decrease of insulin secretion at 30 min. Our data seem to demonstrate that insulin resistance with an inadequate hyperinsulinaemia is a common factor for the alterations of carbohydrate metabolism during pregnancy. Only in the non-obese patients with gestational diabetes, is there an absolute defect of early insulin response to the glucose load, as it is seen in T2DM.

Adult↗
PubMed1998

[Digestive anastomosis in general surgery].

Still today the digestive anastomoses are a subject very discuss and controversial in relation to the better technique. In fact the introduction of mechanical suture has placed the problem between this instrumentation and the classic technique. The Authors, comparing these two techniques, observe the peculiar aspects of each one and relate on the progresses, in last years, whether of the mechanical suture, with the improvement of the handy and the resistance of the anastomosis, or the threads of suture, ever more inert and resistant. Subsequently, the Authors relate your experience showing the form of realization of the anastomoses in the esophagogastric surgery, small intestine, colon-rectum, hepato-biliary and pancreatic surgery. In particularly, about the hand-sewn anastomosis, the Authors relate personal technique of reconstruction with extramucosal continuous suture, one-layer, with synthetic slow absorbable one-filament (PDS). In conclusion, the Authors declare that the introduction of the mechanical suture has certainly influenced the development of the new therapeutic solutions and has allowed intestinal anastomosis in sites of difficult access (abdominal esophagus, low rectum), but they think that the surgeon must to learn to know when is useless or neoplastic mechanical suture and he can realize manually the same anastomosis with quickness and safety.

Anastomosis, Surgical↗
PubMed1997

Identification of a committed T cell precursor population in adult human peripheral blood.

Here, we report data concerning the discovery in adult human peripheral blood of a precursor cell population able to differentiate into CD4+CD3+ alpha beta + mature T cells. These cells, which represent 0.1-0.5% of total peripheral blood mononuclear cells (PBMC), express substantial levels of CD4, but lack CD3 surface expression. At a molecular level, they express the pre-T cell receptor alpha (pT alpha) gene, CD3-gamma, CD-delta and CD-epsilon, and RAG-1 recombination enzyme and have initiated rearrangements in the T cell receptor (TCR)-beta locus (D-J). Moreover, low levels of CD3 epsilon protein, but not of TCR-beta chain, can be detected in their cytoplasm. Our results suggest that CD4+CD3- cells identified in peripheral blood are different from CD3-CD4+CD8- thymocytes and may contain precursors of an extrathymic T cell differentiation pathway.

Adult↗
PubMed1997

Direct in situ transcriptase polymerase chain reaction for the detection of Enterovirus genome in liver tissues.

Adolescent female mice were inoculated intraperitoneally with coxsackievirus B3 Nancy strain, sacrificed 3 and 5 days later and the livers harvested. A protocol for direct reverse transcriptase in situ PCR (RT-ISPCR) detection of enteroviral RNA in paraffin-embedded liver tissues was developed. The optimal conditions for the assay were determined. The best results were obtained when the tissue was fixed in formalin, prior to being embedded in paraffin, then cut in 5 micron thick sections, and mounted onto silanized slides. After deparaffination the slides were incubated in 1 microgram/m1 Proteinase K for 10 min and cDNA synthesis was carried out. For successful RT-ISPCR 40-50 cycles of amplification were necessary. The optimal concentrations of dNTP, primers and Taq Polymerase for RT-ISPCR were determined by serial dilution assays. Primers were selected from highly conserved sequences in the 5' non-coding region (5'NTR). To detect the viral RNA in the liver, digoxigenin-dUTP was incorporated during amplification, subsequently bound with an antidigoxigenin antibody conjugated to alkaline phosphatase (AP), followed by colorimetric detection with nitroblue tetrazolium salt (NBT) and 5-brom-4chloro-3indolyl-phosphate (BCIP). The result was a blue precipitate in the cytoplasm of hepatocytes from infected mice. Fibroblasts, endothelial cells, lymphocytes and the nuclei of hepatocytes were negative. Thus, RT-ISPCR is a specific method for the detection of enterovirus RNA in the hepatocytes of infected mice, and can be of use for the determination of EV liver disease in man.

Animals↗
PubMed1996

RAG1, RAG2 and pre-T cell receptor alpha chain expression by adult human hepatic T cells: evidence for extrathymic T cell maturation.

Flow cytometric analysis of cell suspensions obtained from normal adult liver tissue at the time of transplantation revealed significant populations of T lymphocytes. These were examined for molecular evidence of local T cell maturation using reverse transcription-polymerase chain reaction to detect expression of recombination activation gene 1 (RAG1), RAG2 and pre-T cell receptor alpha chain (pTalpha), which occurs only in early thymocyte development. Four specimens of whole liver were positive for RAG1 and RAG2 expression, whereas peripheral blood mononuclear cells from the same individuals were negative. To localize RAG expression, immature (CD2+CD7+) and mature (CD45R0+) T cell subpopulations were isolated by magnetic separation from hepatic and peripheral blood mononuclear cell preparations. We detected the expression of RAG1, RAG2 and pre-TCRalpha in five specimens of hepatic CD2+CD7+ but not in CD45RO+ hepatic lymphocytes. Four out of six specimens of CD2+CD7+ cells from the peripheral blood were negative for RAG1 and RAG2 while all six specimens were positive for pTalpha expression. These results suggest that pre-T cells are trafficking from the bone marrow or the thymus to other tissues to continue differentiation and selection in the context of an appropriate cellular and molecular environment. The presence of immature populations of T cells in the adult liver and high levels of RAG expression suggests that the adult liver provides such an environment for extrathymic T cell maturation. These findings may have important implications for tolerance induction after liver transplantation and offer help in understanding the etiology of autoimmune liver disease.

Adult↗
PubMed1996

Cell division in the compartment of naive and memory T lymphocytes.

Expression of activation markers and proliferative status were measured in peripheral CD4+ and CD8+ T cells of various T cell receptor (TCR)-transgenic mice either before or after intentional antigenic stimulation. In the absence of intentional immunization, CD4+ T cells persisted as resting or partially activated and cycling cells depending on the specificity of their TCR. Similar results were obtained following transfer into T cell-deficient recipients, i.e. T cells that were not cycling in situ did not cycle after transfer, whereas cells that were proliferating in situ also cycled after transfer. Thus, the TCR of some cells in the absence of intentional antigenic stimulation may bind to some unidentified ligand that does not induce tolerance, but rather slow expansion. In a different sort of experiment, activated T cells that were derived from noncycling naive T cells by deliberate antigenic stimulation continued to cycle slowly even a long time after transfer into antigen-free recipients that did not induce proliferation of the naive cells. Thus, lymphokines or ligands that do not induce activation of naive T cells may be responsible for the maintenance of memory cells. Our experiments show that the latter does not depend on a second TCR expressed by the memory cells, since memory T cells from RAG-2(-/-) TCR-transgenic mice persisted to a similar extent.

Animals↗
PubMed1996

The alpha beta T cell receptor can replace the gamma delta receptor in the development of gamma delta lineage cells.

In peripheral lymphoid tissues of TCR transgenic mice that express the nominal antigen (HY peptide plus H-2Db MHC) recognized by the transgenic TCR, there exist unusual CD4-CD8- and CD4-CD8low cells bearing the transgenic TCR. Here we show that, unlike TCR alpha beta T cells that are generated in the absence of nominal antigen, these unusual cells do not express endogenous TCR alpha genes, have maintained the TCR delta locus on both chromosomes, and can coexpress TCR alpha beta and TCR gamma delta chains on the cell surface. The latter is also true for CD4-CD8-, HSA+ TCR alpha beta + thymocytes in male and female TCR transgenic mice. The number of TCR alpha beta and TCR gamma delta coexpressing cells is increased in pre-TCR-deficient mice. The data indicate that the TCR alpha beta can replace the TCR gamma delta in the development of gamma delta lineage cells and that the pre-TCR interferes with the generation of gamma delta-expressing cells.

Animals↗
PubMed1996

Adjuvant chemotherapy after gastric resection in node-positive cancer patients: a multicentre randomised study.

After curative resection for gastric adenocarcinoma, 103 patients, all with positive nodes, were randomised so that 48 received adjuvant chemotherapy of epidoxorubicin (EPI) 75 mg m-2 on day 1, leucovorin (LV) 200 mg m-2 on days 1-3 and 5-fluorouracil (5-FU) 450 mg m-2 on days 1-3, every 21 days for 7 months, whereas the remaining 55 did not. During the first year of observation, 21 control patients (38%) and five treated patients had recurrences. After a follow-up period of 36 months, 12 of the treated patients (25%) and only seven controls (13%) were still alive. At that point, the median survival was 13.6 months for the 55 untreated patients and 20.4 months for the 48 treated patients, a significant difference. We found a survival advantage for patients treated with the EPI-LV-5-FU regimen and a consistent delay in the appearance of recurrent or metastatic cancer. Acute toxicity was mild and treatment was well accepted by all patients. There was no long-term toxicity or any cardiac toxicity. We conclude that this particular chemotherapy, administered shortly after gastric resection, improves survival rate in node-positive gastric cancer patients, even although final assessment of this particular adjuvant approach must await completion of the trial.

Adenocarcinoma↗
PubMed1995

Cloning and comparative analysis of the human pre-T-cell receptor alpha-chain gene.

In immature T cells the T-cell receptor (TCR) beta-chain gene is rearranged and expressed before the TCR alpha-chain gene. At this stage TCR beta chain can form disulfide-linked heterodimers with the pre-T-cell receptor alpha chain (pTalpha). Using the recently isolated murine pTalpha cDNA as a probe, we have isolated the human pTalpha cDNA. The complete nucleotide sequence predicts a mature protein of 282 aa consisting of an extracellular immunoglobulin-like domain, a connecting peptide, a transmembrane region, and a long cytoplasmic tail. Amino acid sequence comparison of human pTalpha with the mouse pTalpha molecule reveals high sequence homology in the extracellular as well as the transmembrane region. In contrast, the cytoplasmic region differs in amino acid composition and in length from the murine homologue. The human pTalpha gene is expressed in immature but not mature T cells and is located at the p21.2-p12 region of the short arm of chromosome 6.

Amino Acid Sequence↗
PubMed1995

Intra- and extra-thymic expression of the pre-T cell receptor alpha gene.

We have analyzed pre-T cell receptor alpha (pT alpha) gene expression in cells from various anatomical sites to investigate the lineage specificity of pT alpha RNA as well as its presence in pro-T cells and in sites of extrathymic T cell development. pT alpha RNA is found in precursors of alpha beta T cells but is absent from mature alpha beta T cells as well as T cells that express the gamma delta T cell receptor on the cell surface. pT alpha expression is exquisitely T lineage specific in that mature and immature B cells, myeloid cells, NK cells and pluripotent stem cells are pT alpha negative. On the other hand, pT alpha expression is found in pro-T cells outside the thymus as well as in intra- and extra-thymic sites of T cell development. The latter finding is consistent with the notion that early steps of T cell development within and outside the thymus may be similar.

Animals↗
PubMed1995

On the cellular basis of immunological T cell memory.

We have studied memory in T cell receptor (TCR) transgenic mice expressing a Db-restricted TCR specific for the male peptide (H-Y). CD8+ T cells from female TCR transgenic C57BL/6 (B6) mice were activated by transferring them into X-irradiated male (B6 x bm12)F1 hybrid recipients. Subsequently, they were highly purified by cell sorting and transferred for various lengths of time into female B6 nu/nu recipient mice. Other nu/nu recipient mice received highly purified naive T cells expressing the transgenic TCR. The functional potential of naive and "memory" T cells was analyzed by stimulation with male cells in vivo. The results show that memory cells can be derived from activated T cells and persist in the absence of antigen for at least 13 weeks. Naive and memory T cells differ in that memory T cells give a more vigorous and sustained response than naive T cells.

Animals↗
PubMed1995

Presurgical localization of functional cortex using magnetic source imaging.

The boundaries of somatosensory cortex were localized noninvasively by means of a large-array biomagnetometer in six patients with mass lesions in or near eloquent cortex. The results were used by neurosurgeons and neurologists in preoperative planning and for reference in the operating room. The magnetic source imaging (MSI) localizations from somatosensory evoked potentials were used to predict the pattern of phase reversals measurable intraoperatively on the cortical surface, providing a quantitative comparison between the two measures. The magnetic localizations were found to be predictive in all six cases, with the two sets of localizations falling within an 8-mm distance on average. Somatosensory localizations using MSI offer accuracy in localizing somatosensory cortex stereotactically and in depicting its relationship to lesions. Such data are valuable preoperatively in assessing the risks associated with a proposed surgical procedure and for optimizing subsequent minimum-risk surgical strategy.

Adult↗
PubMed1994

Analysis and expression of a cloned pre-T cell receptor gene.

The T cell antigen receptor (TCR) beta chain regulates early T cell development in the absence of the TCR alpha chain. The developmentally controlled gene described here encodes the pre-TCR alpha (pT alpha) chain, which covalently associates with TCR beta and with the CD3 proteins forms a pre-TCR complex that transduces signals in immature thymocytes. Unlike the lambda 5 pre-B cell receptor protein, the pT alpha chain is a type I transmembrane protein whose cytoplasmic tail contains two potential phosphorylation sites and a Src homology 3 (SH3)-domain binding sequence. Pre-TCR alpha transfection experiments indicated that surface expression of the pre-TCR is controlled by additional developmentally regulated proteins. Identification of the pT alpha gene represents an essential step in the structure-function analysis of the pre-TCR complex.

Amino Acid Sequence↗