PubMed Health⌕ Search

Biomedical subjects

M Albrizio

Publications and source records attributed to M Albrizio.

At least 19 recordsLinked to original sources
PubMed2006

Relationship of body mass index to early complications in hip replacement surgery : study performed at Hinchingbrooke Hospital, Orthopaedic Directorate, Huntingdon, Cambridgeshire.

The purpose of this study was to evaluate the relationship between body mass index and early complications following total hip replacements. Five hundred and fifty patients who underwent primary total hip replacement were recruited. All these patients were subjected to a pre-operative assessment and follow-up at 6 weeks and 1 year following surgery. Any complications occurring during this period were recorded. Complications were grouped into systemic and local, both subdivided into minor and major depending on the risk involved. Fifty-six patients (10.2%) had an early complication following hip replacement surgery. Forty-four patients (8%) had a major local complication. Overall, there did seem to be a weak correlation between BMI and the rate of complications, with a p value of 0.104. A correlation was also found between the surgeon and presence of complications with a p value of 0.736. There is a weak correlation between BMI and early complications following hip replacement surgery, and there also seems to be a correlation between the operating surgeon and early complications, but this is not statistically significant.

Adult↗
PubMed2006

Opioid agonist/antagonist effect of naloxone in modulating rabbit jejunum contractility in vitro.

Opioid peptides are the most effective drugs in controlling pain; their action is elicited by binding to specific membrane receptors. The gastrointestinal tract represents, after the nervous system, the site in which the opioid receptors are expressed at high levels. The opioid agonist morphine has a significant inhibitory effect on intestinal motility, this action is blocked by naloxone an opioid antagonist mainly active at mu and kappa receptors. In this study the presence of mu opioid receptor on rabbit jejunum was investigated by western blot. The effects of beta-endorphin, the endogenous opioid peptide with the highest affinity to the mu opioid receptor and those of naloxone on spontaneous rabbit jejunum contractions were evaluated. Beta-endorphin (10(-6) M) showed a relaxant effect on jejunum contractility while naloxone showed a dual effect inducing an increase of spontaneous contractility at low concentrations (10(-6) M, 10(-7) M, 10(-8) M) and a decrease when high concentrations (10(-3) M, 10(-4) M, 10(-5) M) were utilized. The obtained results demonstrate that mu opioid receptor is expressed in rabbit jejunum and suggest that this receptor may be involved in mediating the effects of both opioid agonist and antagonist on jejunum contractions.

Analysis of Variance↗
PubMed2002

Effects of beta-endorphin and Naloxone on in vitro maturation of bovine oocytes.

Bovine cumulus-oocyte complexes (COCs) and mural granulosa cells express the mRNA coding for the micro-opioid receptor. The addition of beta-endorphin (beta-end) to oocytes cultured in hormonally-supplemented in vitro maturation (IVM) medium had no effect on the rates of oocytes reaching the metaphase II (MII) stage, but significantly decreased the maturation rate (P < 0.05) and arrested oocytes at metaphase I (MI) after culture in hormone-free medium (P < 0.001). Naloxone (Nx) reverted this inhibitory effect of beta-end. Moreover, Nx "per se" showed a dose-dependent dual effect. When added at high concentration (10 x (-3) M), it significantly reduced the rate of oocytes in MII (P < 0.001), thus increasing the rate of oocytes arrested in MI. However, Nx added at low concentration (10 x (-8) M) significantly increased oocyte maturation (P < 0.001). High concentration of Nx induced an increase in both intracellular calcium concentration ([Ca(2+)](i)) and in the activity of the mitogen-activated protein kinase (MAPK) also called extracellular-regulated kinase (ERK) in cumulus cells of bovine COCs. Blocking the rise in [Ca(2+)](i) with the calcium chelator acetoxymethylester-derived form of bis (o-aminophenoxy) ethane-N,N,N',N'-tetraacetic acid (BAPTA-AM) reversed the Nx-dependent inhibition of meiotic maturation observed at high Nx concentrations. Whereas blocking ERK with the MAPK/ERK kinase (MEK) inhibitor, PD98059, had no effect on this process. Therefore, we concluded that the mocro-opioid receptor, by inducing [Ca(2+)](i) increase, participates in the cumulus-oocyte coupled signaling associated with oocyte maturation.

Animals↗
PubMed2001

Naloxone inhibits A6 cell Na(+)/H(+) exchange by activating protein kinase C via the mobilization of intracellular calcium.

The opioid receptor antagonist, naloxone, has been shown to have beneficial effects in the kidney and to be implicated in renal salt and water balance. In the present study the signal transduction pathways utilized by naloxone were studied in an epithelial cell line model of the cortical collecting duct, A6 cells. We found that naloxone has a dual effect depending on the concentration used: at a low concentration (10(-6) M) it antagonized the beta-endorphin-dependent increase in cytoplasmic calcium [Ca(2+)](i), while at higher concentrations (>10(-5) M) it increased [Ca(2+)](i) and intracellular inositol phosphate levels. While naloxone-induced increases in [Ca(2+)](i) occurred in the absence of external calcium, it was significantly stimulated by increasing the external calcium concentration, suggesting that naloxone increases [Ca(2+)](i) via both calcium release and calcium influx. In polarized A6 cell monolayers naloxone inhibited the activity of the Na(+)/H(+) exchanger (NHE) only when added to the basolateral cell surface. This inhibition of the NHE was prevented by pretreatment of the cells with either the intracellular calcium chelator, BAPTA or with the protein kinase C inhibitor, calphostin C. These findings demonstrate that naloxone induces a rapid increase in intracellular calcium which inhibits the NHE via the calcium-dependent protein kinase C regulatory pathway.

Animals↗
PubMed1997

Characterisation of CAH alleles with non-radioactive DNA single strand conformation polymorphism analysis of the CYP21 gene.

The major cause of congenital adrenal hyperplasia (CAH), a common recessive genetic disease, is the deficiency of steroid 21-hydroxylase (21OH), a microsomal enzyme encoded by the CYP21 gene. Although several CAH causing mutations have been identified in the CYP21 gene of patients with 21OH deficiency, genotyping of the 21OH locus is quite complex because of the high frequency of gene conversion and the presence of multiple mutations on single CAH alleles. In order to perform the complete characterisation of the CYP21 gene coding region more simply, we developed a highly sensitive, non-radioactive method allowing DNA single strand conformation polymorphism (DNA-SSCP) analysis. This method was applied to the characterisation of all the exons and intron-exon junctions of the CYP21 gene in five patients affected by the simple virilising form and one affected by the salt wasting form. In all samples showing SSCP signals, direct sequence analysis showed the presence of more than one single sequence variant. In particular, four mutations which are already known to cause the disease, 16 polymorphisms, and one newly identified C to T transition at position 849 were detected. A random sequence analysis, performed on 31 out of 81 exons showing a normal SSCP pattern, shows the method to be highly sensitive: no sequence variant was detected, thus confirming the validity of this non-radioactive DNA-SSCP analysis in characterising the CYP21 gene in patients with steroid 21OH deficiency. Notwithstanding the complete characterisation of all exons and exon/intron junctions of the CYP21 gene, no complete genotype/phenotype correlation was found in the panel of patients analysed, thus suggesting that characterisation of CAH alleles must be extended to outside the coding region of the CYP21 gene, most probably into the promoter region.

Adrenal Hyperplasia, Congenital↗
PubMed1995

Polymerase chain reaction in liposomes.

BACKGROUND: Compartmentalization of biochemical reactions within a spherically closed bilayer is an important step in the molecular evolution of cells. Liposomes are the most suitable structures to model this kind of chemistry. We have used the polymerase chain reaction (PCR) to demonstrate that complex biochemical reactions such as DNA replication can be carried out inside these compartments. RESULTS: We describe the first example of DNA amplification by the PCR occurring inside liposomes composed of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC), or of a mixture of POPC and phosphatidylserine. We show that these liposomes are stable even under the high temperature conditions used for PCR. Although only a very small fraction of liposomes contains all eight different reagents together, a significant amount of DNA is produced which can be observed by polyacrylamide gel electrophoresis. CONCLUSIONS: This work shows that it is possible to carry out complex biochemical reactions within liposomes, which may be germane to the question of the origin of living cells. We have established the parameters and conditions that are critical for carrying out this complex reaction within the liposome compartment.

Animals↗
PubMed1995

Tubular adenoma of the breast: an immunohistochemical study of ten cases.

Ten cases of so-called "tubular" adenoma and six cases of fibroadenoma of the breast have been investigated with an immunohistochemical technique with the aim of providing both more details on their immunophenotype and of ascertaining the possible relationships between tubular adenoma and fibroadenoma. Smooth Muscle Actin, Cytokeratin 14, GFAP, S-100 Protein and Vimentin immunoreactivity have clearly demonstrated that cells with myoepithelial immunophenotype are one of the major cell components in breast adenomas. Epithelial Membrane Antigen (EMA), Human Milk Fat Globule II (HMFG II), Estrogen and Progesterone receptors have been detected in adluminal epithelial cells exclusively. Furthermore, Smooth Muscle Actin and Vimentin highlighted an abundant myofibroblastic component, intermingled with tubular structures in both tumor types. A low percentage (10-22%) of adluminal cells and of myofibroblasts showed Ki-67 immunoreactivity in tubular adenomas and in fibroadenomas, whereas only rare myoepithelial cells demonstrated Ki-67 positivity in both tumor types. These data seem to indicate that several cell components of both epithelial and mesenchymal origin (epithelial cells, myoepithelial cells, myofibroblasts) are involved in the genesis of tubular adenomas. The morphological and immunohistochemical features of tubular adenomas closely resemble, in some areas of the tumors, those of fibroadenoma. Therefore, they may represent histogenetically related neoplasms with exuberant ductular component in tubular adenomas and predominant stromal component in fibroadenoma.

Actins↗
PubMed1992

Occupational exposure to asbestos and urinary bladder cancer.

By the use of transmission electron microscopy (TEM) and energy dispersion spectrometry the amount (mean value mean = 191 +/- 94 fibers/mg of tissue) and the type (chrysotile and tremolite) of asbestos fibers have been determined in tissue samples of four bladder cancer patients affected by pulmonary asbestosis, working in the same plant producing asbestos-cement pipes and boards. Similar measurements were carried out on samples of bladder cancers of eight control patients not professionally exposed to asbestos. Only five of them also revealed chrysotile fibers (mean = 151 +/- 196 fibers/mg of tissue). The paucity of the study and control cases and the small quantitative difference between them regarding the presence of infraneoplastic asbestos fibers does not consent us to hypothesize a causal relationship between tumor and occupational exposure.

Aged↗
PubMed1992

An exploration of the variables involved when instituting a do-not-resuscitate order for patients undergoing bone marrow transplantation.

Written do-not-resuscitate (DNR) orders can facilitate the transition from aggressive care to supportive care in patients undergoing bone marrow transplantation who are critically ill. The DNR decision often is complicated by clinical and ethical problems. To assist nurses in analyzing these complex situations, a retrospective review was conducted on medical records of 40 patients who died on an eight-bed bone marrow transplant unit in which a formal DNR policy was in place. A review of specific variables for patients designated DNR and non-DNR showed that the groups did not vary in age, diagnosis, disease, or type of transplant. The non-DNR group developed life-threatening complications earlier in their transplant course, whereas multisystem failure was the common factor among the patients with DNR designation. The few ethical problems documented in the medical records did not appear to reflect the complexity of the DNR decision.

Adolescent↗
PubMed1990

[Ileal stenosis caused by chronic granulomatous inflammation secondary to a foreign body simulating Crohn disease].

A case of ileal stenosis due to foreign body induced chronic granulomatous inflammation simulating Crohn's disease with onset on an ileo-ileostomy carried out 23 years before due to iatrogenic rupture of ileal loop following clandestine abortion is reported. After noting the problem of attributing to the foreign body alone responsibility for the stenosis, the hypothesis that it might have been an acute occurrence of Crohn's disease or the expression of an association of Crohn's disease and granulomatous inflammation due to surgical material is advanced. This for the moment is the only plausible cause. It is concluded that for accurate nosological classification and, therefore, definitive clinical diagnosis, prolonged clinical control of the patient is indispensable.

Constriction, Pathologic↗
PubMedDate not supplied

Immunohistochemical reactivity of anti-melanoma monoclonal antibody 225.28S in human breast cancer biopsies.

The high molecular weight melanoma-associated antigen, defined by murine monoclonal antibody (IgG1) 225.28S is largely expressed by melanoma cells and weakly expressed by other human tumors originating from neural crest. In this study, we analyzed the immunohistochemical reactivity of MoAb 225.28S in human breast cancer biopsies. A total of 92 breast cancer biopsies (66 infiltrating lobular and 26 infiltrating ductal carcinomas) were initially tested along with 26 melanomas (positive controls), 23 gastric/colonic adenocarcinomas and 13 neuroendocrine tumors. Forty-four out of 66 lobular breast carcinomas showed positive immunostaining with 225.28S MoAb as well as only 6 out of 26 infiltrating ductal histotype and 12 out of 26 melanomas. Conversely, gastric and colonic adenocarcinomas and neuroendocrine tumors were completely negative. The pattern of positivity in breast carcinomas was associated with malignant cells, rather than with the stroma or histiocytes infiltrating the lesions. Nonspecific cross-reactivity of 225.28S with breast carcinomas was excluded using a similar murine antithyreoglobulin MoAb, which gave negative staining in all biopsies. These results indicated that HMW-MAA or a similar sequence recognized by 225.28S MoAb is often expressed by lobular breast carcinomas but rarely by ductal adenocarcinomas. This seems to suggest that lobular breast carcinoma has common "ancestor" antigens with melanoma.

Antibodies, Monoclonal↗
PubMedDate not supplied

[Identification of mucin-secretion characteristics in cells from serous effusions: consideration of histochemical and immunohistochemical aspects].

Fourty-two cell-blocks of serous effusions (thirty malignant and twelve reactive) were tested by anti Secretory Component Ab (policlonal) using the s.-Ab method, and by histochemical tests: PAS, PAS Diastase and Alcian blue pH 2.5. Immunohistochemical and histochemical features were compared to identify their meaning and correlation in epithelial mucin detection. This study suggests the evident correlation between SC and PAS diastase (better than between SC and Alcian blue) and possibility to replace the old traditional test of PAS diastase with anti SC antibody (much more sensible than PAS diastase) in routine mucin detection histochemical tests.

Alcian Blue↗
PubMedDate not supplied

[Right temporo-occipital ganglioglioma in a 10-year-old patient].

Authors describe an operated case of ganglioglioma of the right temporo-occipital region in a ten year old patient. After case presentation and an analysis of the literature, the diagnostic pre-operative problems are discussed analysing the CT aspects of the lesion.

Brain Neoplasms↗