Biomedical subjects

G Biagini

Publications and source records attributed to G Biagini.

At least 73 records · Page 4Linked to original sources

PubMed1997

An experimental pilot study of tacalcitol activities during modulation of parakeratotic skin features.

Establishing guidelines and experimental models preclinical and clinical evaluations of new agents for treatment, and/or prevention of human diseases has become a task of crucial importance. Psoriasis is such one disease holding great interest for dermatology owing to its high rate of incidence and complexity of treatment. However the absence of psoriatic lesions in animals and the inability to induce them, calls for experimental techniques both in vitro and in vivo. The purpose of this study was to evaluate experimentally the effects of tacalcitol on cell proliferation and differentiation process. Thereafter a human pilot study on psoriatic patients has been developed.

Administration, Topical↗

PubMed1996

In vitro study of gingival fibroblasts from normal and inflamed tissue: age-related responsiveness.

The aim of this study was to characterize some phenotypic expressions of fibroblasts from the human oral mucosa. Gingival and lower forearm fibroblasts from young (20-30 years) and elderly (> 60 years) subjects were analyzed. Gingival fibroblasts were taken from donors with (P) and without (NP) periodontal disease, while skin biopsies were taken from healthy subjects. Cell proliferation was assessed by evaluating the cell multiplication coefficient (C.M.C.). The proliferation potential of gingival fibroblasts from elderly individuals with and without periodontopathy did not differ from that of young subjects in the same condition but differed significantly in the skin samples. Enzyme neutral endopeptidase (EC 3.4.24.11) (NEP) activity, studied as a possible marker of cell ageing, showed an age-related increase in human skin fibroblasts but not consistently in gingival fibroblasts from individuals with or without periodontal disease. Cell area and substrate adhesion were evaluated by morphometric analysis. There were no significant differences between elderly P and NP subjects, while significant differences were observed between young and elderly P subjects. In conclusion, proliferative capacity and NEP activity in gingival fibroblasts did not appear to be age-related, probably because their microenvironment is continually moistened by saliva, which continues to contain growth factors, notably EGF, even into senescence. Tissue reaction and repair are important clinical and therapeutic implications.

Adult↗

PubMed1996

The 72-kDa metalloproteinase immunostaining in cervical carcinoma: relationship with lymph nodal involvement.

OBJECTIVE: In the present study we detected 72-kDa metalloproteinase expression in our series of early stage cervical carcinomas and analyzed the relationship between 72-kDa metalloproteinase staining and risk of nodal involvement with the goal of identifying a parameter useful in predicting the metastatic potential of lesions. MATERIALS AND METHODS: The medical records of 34 patients with FIGO stage I squamous cell cervical carcinoma who had undergone primary radical surgery with systematic pelvic and para-aortic lymphadenectomy (Piver's type III) at the Institute of Gynecologic and Obstetrics, Ancona University, between January 1988 and January 1993 were recruited from our series of 57 consecutive cases and reviewed. Any characteristic that could be relevant for prognosis was recorded in all of the cases: histologic grade of differentiation, tumor size, lymphatic spread, and adjuvant radiotherapy. Immunohistochemical staining was performed on serial sections of tumors using the avidin-biotin complex technique (Vector Laboratories, Burlingame, CA). The affinity-purified rabbit anti-72-kDa metalloproteinase antibody was used. Positive staining was expressed as a percentage of positive cells per 10(3) counted neoplastic cells (the 72-kDa metalloproteinase index). RESULTS: The tissue 72-kDa metalloproteinase immunoreactivity was diffusely expressed in all cervical carcinomas (ranging from 8.6 to 51.9%, with a median of 17.8%) and showed a significant relationship with respect to lymphatic spread. In the presence of lymph nodal involvement, the 72-kDa metalloproteinase index was significantly higher than in the absence of nodal metastasis (32.9 +/- 12.2% versus 18.1 +/- 9.0%, means +/- standard deviations with P = 0.001); a significant relationship was also observed between the 72-kDa metalloproteinase index and the number of positive nodes (r = 0.8, with P = 0.01). No significant relationship was defined with respect to the other prognostic parameters. The Cox proportional hazard analysis showed a significant relationship between the 72-kDa metalloproteinase index and disease-free survival (P < 0.0001) that was independent of tumor size, nodal involvement, and lymphvascular space invasion. CONCLUSIONS: Although the small numbers do not allow any definitive conclusion, a significant relationship between the 72-kDa metalloproteinase index and the risk of lymphatic spread is defined in early stage cervical carcinoma. The 72-kDa metalloproteinase immunostaining seems to have a prognostic value, suggesting the possibility of an association between neoplastic aggressiveness and 72-kDa metalloproteinase expression.

Adult↗

PubMed1996

Recurrence patterns in locally advanced cervical carcinoma: role of nodal status and 72-kDa metalloproteinase index.

OBJECTIVE: The aim of the study was to analyze the relationship between lymph nodal involvement and regional and/or distant recurrences in locally advanced squamous cervical carcinomas, and also evaluate tumor 72-kDa metalloproteinase, as a biologic parameter useful for understanding the mechanisms of disease relapse and prognosis. In particular, 72-kDa metalloproteinase is an enzyme that specifically cleaves type IV collagen and seems to play a critical role in tumor invasion and metastatic dissemination. METHODS: The medical records of 62 patients with FIGO (International Federation of Gynecology and Obstetrics) stage Ib and IIa squamous cervical carcinoma who underwent primary radical surgery with systematic pelvic and paraaortic lymphadenectomy and then were routinely followed were recruited from our series of 76 consecutive cases and reviewed. Fifty-four patients with complete clinicopathologic information were considered eligible for the study. All recurrences were defined as histologically and/or cytologically documented disease, following a minimum 3-month disease-free interval. Sites of recurrences were classified as distant, or regional to the pelvis. Immunostaining with 72-kDa metalloproteinase was performed on serial sections of tumors using avidin-biotin complex technique. Affinity-purified rabbit anti-72-kDa metalloproteinase antibody was used. Positive staining was expressed as a percentage of positive cells per 10(3) counted neoplastic cells (72-kDa metalloproteinase index). RESULTS: After a median follow-up of 38 months (range 9-71 months), 11 patients recurred with a 20% overall incidence. Seven patients (64%) recurred regionally, with side-wall infiltration in 2 cases, and 4 patients (36%) recurred distantly. By Cox hazard multivariate analysis, lymph nodal status was significantly related to disease-free survival (P = 0.01); in particular, all the patients with side-wall or distant recurrences had lymph nodal involvement. A significant relationship was also observed between tumor 72-kDA metalloproteinase immunostaining and disease-free survival (P = 0.02). The 72-kDA metalloproteinase index was significantly higher in patients who recurred than in patients with disease-free follow-up (P < 0.001); in particular, the highest values were detected in patients who recurred distantly. A relationship between 72-kDa metalloproteinase staining and nodal status was observed (P < 0.001). CONCLUSIONS: In conclusion, nodal status and the 72-kDa metalloproteinase index were two independent prognostic parameters, significantly related to recurrence risk and pattern of recurrence in locally advanced cervical carcinoma. Although they are independent prognostic parameters, a relationship between nodal involvement and 72-kDa metalloproteinase was observed. A model of tumor recurrence in which intrinsic tumor factors exert their negative influence directly or by contributing to the development of nodal metastases seems possible.

Animals↗

PubMed1996

Microinvasive cervical carcinoma and cervical intraepithelial neoplasia: biologic significance and clinical implications of 72-kDa metalloproteinase immunostaining.

OBJECTIVE: The immunohistochemical expression of 72-kDa metalloproteinase was evaluated in cervical intraepithelial neoplasia (CIN) and microinvasive carcinoma, with the aim to define a relationship between 72-kDa metalloproteinase expression and neoplastic invasiveness, useful to identify subsets of intraepithelial lesions with higher risk of progression. MATERIALS AND METHODS: Cervical bioptic samples were obtained consecutively from 54 women who attended our Colposcopic Service from January 1993 to July 1993 because of abnormal pap smear, suspicious for cervical dysplasia and/or human papillomavirus infection. After written consent, 29 women with CIN were included in the study. All women with CIN 3 lesion underwent conization; in 21 women with mild or moderate cervical dysplasia, we did not perform any medical or physical treatment but followed them longitudinally at close interval. After 12 months, the clinical evolution was classified as spontaneous remission, persistence, or progression depending on the absence or presence of lesion and/or HPV infection in colposcopy, histology, and polymerase chain reaction findings. In the study we also included surgical specimens from 10 women with microinvasive squamous carcinoma who underwent primary radical surgery. Seventy-two kilodalton metalloproteinase positivity was immunohistochemically stained on serial sections by using the avidin-biotin complex technique (Vector Laboratories, Burlingame, CA) and expressed as percentage of cells per 10(3) counted neoplastic cells. RESULTS: Cytoplasmatic positive 72-kDa metalloproteinase immunostaining was significantly higher in microinvasive cervical carcinomas than in CIN lesion (Student's t test; P < 0.001). Considering only cervical intraepithelial neoplasias, a significant increase in 72-kDa metalloproteinase immunostaining was observed with CIN degree increasing (one-way analysis of variance; P = 0.002). No correlation was found between 72-kDa metalloproteinase immunostaining and HPV infection and lesion size defined by quadrants of the cervix involved with colposcopically evident dysplasia. By analyzing 72-kDa metalloproteinase positivity, regressive dysplasia showed low values of 72-kDa metalloproteinase immunostaining (median 1.2%, range 0.5-1.8%), while persistent (median 2.6%, range 1.9-3.6%) and progressive lesions (median 4.6%, range 2.3-6.9%) presented a significantly higher positivity (one-way analysis of variance; P < 0.001). DISCUSSION: In conclusion, the 72-kDa metalloproteinase expression is related to invasive potential with a significant increase in staining positivity in microinvasive carcinomas; 72-kDa metalloproteinase is detectable in cervical dysplasia, and it is related to the severity of cellular atypia. A clinical implication of 72-kDa metalloproteinase immunostaining seems to be indicated, by analyzing the differences in 72-kDa metalloproteinase positivity rates between regressive and persistent or progressive disease.

Adult↗

PubMed1996

Structural features of latex gloves in dental practice.

The aim of this study was to define from a morpho-structural point of view, using scanning electron microscopy, the features of various types of disposable latex gloves commonly used in Italian dental practice (Biogel D, Trend, Pagni, J&J, Latechnics, Pehasoft, Bantex). None of the brands examined was free from morphological flaws; however, while in some of these only slight depressions were found (Biogel D, Trend), in others (Latechnics, Bantex) there was a marked lack of homogeneity in the latex structure or real holes (Pehasoft). This study emphasizes the current difficulties faced by dentists in the search for safe working conditions.

Biocompatible Materials↗

PubMed1996

Computer-assisted mapping of basic fibroblast growth factor immunoreactive nerve cell populations in the rat brain.

We have performed a mapping of basic fibroblast growth factor (bFGF) immunoreactive (ir) glial and nerve cell populations in the male rat brain using a rabbit antibody raised against a synthetic peptide of bovine bFGF. Regional morphometric and microdensitometric analysis of the bFGF ir neuronal profiles in coronal brain sections was carried out by means of an automatic image analyser. The density and intensity of the bFGF ir glial profiles were subjectively evaluated. The bFGF immunoreactivity (IR) was detected within the cytoplasm of neurons, except within the pyramidal neurons of hippocampal CA2 region, the fasciola cinerea and the indusium griseum, where bFGF IR was present in the nucleus. In contrast, in glial cells bFGF IR was always found in the nucleus. Neuronal and glial IR was no longer observed after absorption of the bFGF antiserum with recombinant bFGF. Basic FGF IR was found in neuronal and glial cell populations throughout the brain as well as in the choroid plexus and in the ependymal cells lining the ventricles. Basic FGF ir nerve cells were found in all layers of both the neocortex and allocortex. Within the caudate putamen and the nucleus accumbens a low density of weak bFGF ir neuronal profiles was detected. The majority of the thalamic nuclei showed medium to high densities of moderate to strong bFGF ir neuronal profiles. All the hypothalamic nuclei, with the exception of the anterior and lateral hypothalamic area and of the ventral hypothalamic nucleus, contained a high density of bFGF ir profiles. The pons and the medulla oblongata were characterized by the presence of a large number of nuclei containing moderate to high densities of strong bFGF ir profiles. The Purkinje cell layer of the cerebellar cortex contained a high density of moderately bFGF ir profiles. A moderate density of strong bFGF ir nerve cell profiles was observed within all the laminae of the spinal cord, except within the II and III laminae where a high density of strongly ir profiles was found. Histogram analysis of total immunoreactivity showed that the distribution of bFGF ir profiles within the telencephalon and mesencephalon tend to be similar with regard to the central tendency and spread. Using Kendall's tau, a significant correlation between intensity and density values was obtained only in the diencephalon. The cytoplasmic bFGF IR found in distinct nerve cell populations all over the rat brain and spinal cord may represent forms of bFGF which can be released from the nerve cells via non-exocytotic mechanisms in view of the absence of an intracellular signal peptide in bFGF. The presence of nuclear bFGF IR within the glial cells all over the central nervous system (CNS) suggests an intracellular function of bFGF, such as the promotion of mitogenesis and/or participation in the transcriptional regulation of various genes.

Animals↗

PubMed1996

Activation of endothelial cells during insulin-dependent diabetes mellitus: a biochemical and morphological study.

Plasma membrane lipid dynamics and cellular morphology were evaluated in endothelial cells obtained from umbilical cords of five women affected by insulin-dependent diabetes mellitus (IDDM) and six healthy pregnant women of similar age and gestational age. Endothelial cells were prepared by an adaptation of the method of Jaffe et al. Membrane fluidity was studied by means of the steady-state fluorescence anisotropy (r) of 1-(4-trimethylaminophenyl)-6-phenyl-1,3,5-hexatriene (TMA-DPH), a fluorescent probe specifically anchoring at the membrane surface. Fluid phase endocytosis was evaluated by the measurement of the changes in fluorescence intensity of TMA-DPH at various times, owing to the internalization of the fluorescent marker in endocytic vesicles. The morphological and morphometric studies were performed by means of transmission electron microscopy (TEM). Endothelial cells obtained from IDDM women showed: (a) increased fluidity of the superficial region of the plasma membrane; (b) a more active fluid phase endocytosis compared with cells from healthy women; (c) increase in mitochondrial area, Weibel-Palade bodies and rough reticulum with wide cisternae. No statistically significant correlation was found between metabolic control and membrane fluidity and endocytosis. All the observed modifications suggest the presence of endothelial cell activation with membrane reshaping during IDDM. These alterations might play a central role in the pathophysiology of atherosclerosis and microangiopathy associated with diabetes mellitus.

Adult↗

PubMed1996

An electron microscopic study of clinical and laboratory-derived strains of teicoplanin-resistant Staphylococcus haemolyticus.

Staphylococcal resistance to glycopeptides (which involves more teicoplanin than vancomycin) is uncommon and largely confined to Staphylococcus haemolyticus, an emerging nosocomial pathogen with a tendency to develop antibiotic resistance. In this study, six S. haemolyticus strains, including two isogenic pairs of teicoplanin-susceptible/-resistant strains and two resistant clinical isolates, were used in a morphologic and morphometric electron microscope investigation. Cells from both clinical and laboratory-derived teicoplanin-resistant strains exhibited abnormally roughened, irregular outlines when observed by transmission electron microscopy. However, no significant differences in cell wall thickness resulted from morphometric analysis when the susceptible/resistant cells of the two isogenic pairs were compared. By scanning electron microscopy, an abnormally roughened, blistered surface was associated with teicoplanin-resistant cocci. A certain variability was noted between strains, not clearly related to the resistance level. In freeze-fracture investigations, a higher number per square micrometer of intramembrane particles, more significant in the E than in the P membrane fracture face, was observed in the laboratory-derived resistant clones as compared to susceptible parent strains. Further studies are needed to understand the cause-effect relation between these ultrastructural alterations and staphylococcal resistance to teicoplanin (but not to vancomycin).

Anti-Bacterial Agents↗

PubMed1996

72-kilodalton type IV collagenase, type IV collagen, and Ki 67 antigen in serous tumors or the ovary: a clinicopathologic, immunohistochemical, and Serological study.

The immunohistochemical expression of 72-kDa type IV collagenase [matrix-metalloproteinase (MMP)-21], basement membrane component type IV collagen and proliferation-related antigen Ki 67 were investigated in 43 benign, borderline, and malignant serous tumors of the ovary. The results were compared with the histotypes of ovarian serous tumors and with their clinical behavior. Serum evaluation of MMP-2 was performed in 14 patients with cystadenocarcinoma and the data compared with that of a control group. The basement membrane (BM) was continuous in benign cystadenomas and in some borderline tumors, whereas it was discontinuous or absent in other borderline tumors, in borderline tumors with microinvasion, and cystadenocarcinomas. The percentage of MMP-2- and Ki 67-expressing cells increased from cystadenomas to borderline tumors, being the highest in malignant tumors; a frequent basal disposition of the MMP-2 cytoplasmic granules also was observed in cystadenocarcinomas. Statistical analysis demonstrated that MMP-2 expression was inversely related to BM integrity. Serum MMP-2 values did not differ from that of the control group. Cox regression analysis showed that tumor stage and grade were significant prognostic factors, whereas MMP-2 and Ki 67 immunohistochemical expression added no further significant information to the prognosis. The investigators conclude that the correlation between increasing MMP-2 expression and BM alteration gives support to the hypothesis of a direct role of the metalloproteinase in the process of destructive stromal invasion. MMP-2, type IV collagen, and Ki 67 immunodetection varied according to the histologic classification of ovarian serous tumors. However, neither these factors nor the serum evaluation of MMP-2 appear useful as prognostic predictors in this series.

Antibodies, Monoclonal↗

PubMed1996

MIB 1 immunostaining in cervical intraepithelial neoplasia: prognostic significance in mild and moderate lesions.

OBJECTIVE: MIB 1 is a new monoclonal antibody which recognizes nuclei of proliferating cells throughout the cell cycle except during the G0 and early G1 phases. In the present study we analyzed the MIB 1 immunostaining as an index of cellular proliferation in cervical intraepithelial neoplasia (CIN) and microinvasive carcinoma, with the aim to identify a relationship with the degree of dysplastic lesion and the risk of neoplastic progression. A correlation between the MIB 1 index and human papillomavirus (HPV) DNA presence was also investigated METHODS: Cervical bioptic samples were consecutively obtained from 86 women who attended our Colposcopic Service from January 1993 to June 1994, because of abnormal pap smears suspicious for cervical dysplasia and/or HPV infection. On histologic evaluation, 41 women had CIN, 23 cervical condyloma, and 22 squamous metaplasia. Ten patients with microinvasive squamous cervical carcinoma, matched for age and demographic characteristics, were selected from our series of cervical carcinomas and immunohistochemically analyzed. The expression of primary tumor cellular proliferation was immunohistochemically evaluated by monoclonal MIB 1 antibody (Immunotech, Marseille Cedex, France) on microwave oven-processed formalin-fixed paraffin-embedded tissue. Positive staining was expressed as the percentage of positive cells per 10(3) counted dysplastic cells for each case. RESULTS: A progressive significant increase in positive MIB 1 immunostaining was observed from squamous metaplasia to microinvasive carcinoma throughout the CIN lesions (p < 0.001). Considering only CINs, the MIB 1 index showed a significant increase with respect to CIN degrees (p < 0.001); no correlation was found between MIB 1 immunostaining and HPV infection, and lesion size. By analyzing the MIB 1 index with respect to CIN outcome in mild and moderate dysplasias, regressive lesions had lower values of MIB 1 immunostaining, while persistent and progressive lesions presented significantly higher positivity (p < 0.001). CONCLUSIONS: Our data demonstrated: (1) that positive MIB 1 immunostaining increased progressively from squamous metaplasia to CIN and microinvasive carcinoma, suggesting that neoplastic transformation is associated with a dysfunctional proliferation of cervical epithelium; (2) that there was a significant correlation between the MIB 1 index and CIN degree but not with respect to HPV DNA presence, and (3) that MIB 1 immunostaining might be useful for a clinical evaluation of mild and moderate dysplastic lesions. However, a much larger study needs to be done over a longer period of time to truly determine the value of the technique in prognostically predicting which lesions might or might not regress.

Adult↗

PubMed1995

Morpho-functional modifications of human syncytiotrophoblast plasma membrane during pregnancy induced hypertension.

A decrease of Na+/K(+)-ATPase activity has been reported in syncytiotrophoblast plasma membrane (SPM) obtained from pregnancy induced hypertensive (PIH) women. The aim of the present work was to verify if the reported modifications in activity are due to a decreased number of enzymatic molecules or to a conformational change of the enzyme itself. Morphological studies were performed in order to better understand the relations between the enzymatic protein and the lipid bilayer. Kinetic studies were also performed. SPM obtained from PIH showed: i) an increased affinity of Na+/K(+)-ATPase for ouabain binding, ii) a significant change in the maximum velocity of the enzyme, iii) a higher distribution factor (DF) of intramembrane particles (IMPs) in the exoplasmic face of the membrane, iv) a decreased mean diameter of IMPs both in the protoplasmic and exoplasmic faces, v) a decreased number of IMPs in the exoplasmic face. In conclusion, a conformational modification seems to be at the basis of the decreased Na+/K(+)-ATPase activity during PIH as suggested by binding, ultrastructural and kinetic data herein reported.

Adult↗

PubMed1995

Ex vivo demonstration of nitric oxide in the rat brain: effects of intrastriatal endothelin-1 injection.

Nitric oxide (NO) is a novel transmitter with multiple functions in endothelium and neuronal tissue. In particular, it has been implicated in the pathogenesis of neurodegenerative diseases. The aim of the present study was to demonstrate the ex vivo detection of NO in basal conditions and after ET-1 intrastriatal injection by means of electron paramagnetic resonance (EPR) spectroscopy using locally injected hemoglobin (Hb) as a NO trapping agent. The extent of neostriatal damage after Hb and ET-1 injections was assessed by means of immunocytochemistry with a monoclonal antibody against dopamine and cAMP-phosphoprotein M(r) 32 (DARPP-32), which is considered a marker of striatal intrinsic neurons. In the absence of local Hb injection, no signal related to endogenous NO was detected in the neostriatum, suggesting that endogenous NO trapping agents are not sufficiently concentrated to allow NO detection with the present technique. Instead, 1 h after Hb injection, a clear nitrosyl-Hb signal can be detected in neostriatal homogenates. ET-1, a powerful vasoconstrictor agent, was used to cause neuronal loss in the neostriatum. No change in nitrosyl-Hb signal was observed in neostriatal 1 h after ET-1 injection, whereas an almost 3-fold increase in the signal intensity was present 24 h after ET-1 injection. The analysis of neostriatal damage showed that Hb injection did not cause either significant damage of striatal tissue or potentiation of ET-1-induced lesions. In conclusion, the present technique allows ex vivo detection of NO in the brain. The delayed increase in NO observed after ET-1 injection indicates that this molecule may participate in the development of slowly progressive neuronal damage occurring at late post-ischemic times.

Animals↗

PubMed1995

Diethyldithiocarbamate, a superoxide dismutase inhibitor, counteracts the maturation of ischemic-like lesions caused by endothelin-1 intrastriatal injection.

The effects of a focal lesion induced by endothelin-1 (ET-1, 0.8 microgram/0.8 microliter) on superoxide dismutase (SOD) were studied in the neostriatum of male rats. SOD activity was analyzed at several time intervals (5, 20, 60 min, 4, 24 h and 7 days) after the lesion. No significant changes were observed early after the injection, but SOD activity started to rise significantly at the 60-min time interval reaching a peak 24 h after the injection. In a second experiment the volume of ET-1-induced lesion was evaluated following treatments which induce variations of SOD activity. ET-1 caused a large lesion (9.20 +/- 1.32 mm3) in the neostriatum 24 h after the injection that was 3-fold greater than that observed 1 h after. Rats treated with the SOD inhibitor diethyldithiocarbamate showed a lesion equivalent to that observed 1 h after ET-1 injection, suggesting that SOD may be involved in the maturation of ET-1-induced neuronal damage.

Animals↗

PubMed1995

Biochemical-morphological modifications of platelet membranes during pregnancy-induced hypertension.

A platelet (PLT) function modification has been reported in normal pregnancies compared with the nonpregnant condition and it has been hypothesized to play a central role in the pathogenesis of pregnancy-induced hypertension (PIH). The aims of the present study were (i) to evaluate the lipid composition, fluidity at different depths, transport functions, and ultrastructural features of the PLT membrane in PIH and (ii) to ascertain whether similar modifications may be determined by the state of pregnancy in comparison with the nonpregnant condition. The platelets of healthy pregnant women (HPW) showed: (i) an increase in Ca2+ ATPase activity, (ii) a decreased fluidity of the deeper site of the membrane, (iii) a reduced cholesterol concentration, with an increased ratio between unsaturated and saturated fatty acids; (iv) a decreased intramembranous particles (IMP) distribution factor (DF) of the plasma membrane E face in comparison with healthy nonpregnant women. When comparing women affected by PIH with HPW, we observed (i) reduced Na+/K+ ATPase activity and enhanced Ca2+ ATPase activity and intraplatelet calcium concentrations, (ii) an increased membrane fluidity, (iii) an increased cholesterol concentration and ratio between unsaturated and saturated fatty acids, (iv) a reduction of the IMP number and the DF. Pregnancy produces a deep modification of the platelet plasma membrane, and PIH produces a more pronounced alteration of the maternal platelets, which can be responsible for the observed modifications in placental blood flow and in the fetomaternal exchange.

Blood Platelets↗

PubMed1995

Ki67 antigen immunostaining (MIB 1 monoclonal antibody) in serous ovarian tumors: index of proliferative activity with prognostic significance.

The purpose of this study was to evaluate the biological significance of Ki67 antigen expression in serous ovarian tumors, through the analysis of MIB 1 monoclonal antibody reactivity in cystoadenomas, borderline tumors, and invasive cystoadenocarcinomas; the correlation between this index of cell proliferation and clinicopathologic parameters (FIGO stage and grade, and disease-free survival) was also investigated in invasive cystoadenocarcinomas. Fifty-four patients with serous ovarian tumors, treated at the Institute of Gynecologic and Obstetrics, Ancona University, Italy, were used as study population; 10 women had serous cystoadenoma, 16 women had serous borderline tumor, and 28 women had invasive cystoadenocarcinoma. The expression of primary tumor proliferation related to Ki67 antigen was immunohistochemically evaluated by monoclonal MIB 1 antibody (Immunotech, Marseille Cedex, France) on microwave oven-processed formalin-fixed paraffin-embedded tissue. Compared to cystoadenomas and borderline tumors, the tissular Ki67 antigen immunostaining was significantly higher in cystoadenocarcinomas, with the highest values in architectural grade 2 and 3 neoplasms (P < 0.001). Within the cystoadenocarcinomas, a relationship was observed between the measured proliferation index and disease FIGO stage, but it was not significant (P = 0.92). However, patients who recurred and/or had disease progression presented a primitive neoplasm with significantly higher expression of Ki67 antigen than that of patients with disease-free survival (P = 0.01). A significant relationship was observed between the Ki67 index and disease-free survival, independent of histologic grade and stage, evaluated by Cox hazards analysis (P = 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1995

MIB 1 immunostaining in stage I squamous cervical carcinoma: relationship with natural killer cell activity.

The aim of the study was to investigate the prognostic significance of estimating tumor cell proliferation in stage I cervical squamous carcinoma by analyzing MIB 1 immunostaining with respect to the lesion size, lymphatic spread, and clinical outcome. A possible relationship between MIB 1 index and natural killer activity was also discussed. The medical records of 34 patients with stage I squamous cervical carcinoma who had undergone primary radical surgery at the Institute of Gynecologic and Obstetrics, Ancona University, between 1988 and 1993, were recruited from our series of 57 consecutive cases and reviewed. Thirty-one patients were considered eligible for the study and evaluated for age, demographic characteristics, tumor histologic grade, tumor size, lymphatic spread, and adjuvant radiotherapy. The expression of primary tumor proliferation related to Ki67 antigen was immunohistochemically evaluated by monoclonal MIB 1 antibody (Immunotech, Marseille Cedex, France) on microwave oven-processed formalin-fixed paraffin-embedded tissue. The basal natural killer cell activity of peripheral blood lymphocytes was evaluated against K562 cell line and expressed in lytic units for each patient. The MIB 1 immunostaining was significantly related with tumor size (P = 0.001) and lymphatic spread (P = 0.009); in contrast, there was no relationship between grade of histologic differentiation and MIB 1 immunostaining. The Cox proportional hazards analysis showed a significant independent relationship between MIB 1 immunostaining and disease-free survival (P = 0.004). The analysis of natural cytotoxicity defined a significant inverse relationship between peripheral blood lymphocyte's natural killer activity and tumor MIB 1 immunostaining (r = -0.07, with P = 0.03). Our data defined the prognostic significance of tumor cell proliferation immunostaining, an interesting parameter correlated with the disease-free survival in locally advanced cervical carcinoma. The relationship between MIB 1 index and natural killer activity is interesting; natural cytotoxicity seems to be altered in the host with respect to the cervical carcinoma characteristics.

Adult↗

PubMed1995

Effect of endothelin-1 induced ischemia on peroxidative damage and membrane properties in rat striatum synaptosomes.

Synaptosomes obtained from rat striata lesioned by central injection of endothelin-1 (ET-1) were analyzed for the levels of lipid peroxidation products, the susceptibility to lipid peroxidation, the phospholipid and free fatty acid composition and the activity of Na+,K(+)-ATPase one hour after ET-1 treatment. The intrastriatal injection of ET-1 promoted an increase of endogenous thiobarbituric reactive substances (TBARS), as index of free radical mediated lipid damage, and a greater susceptibility to iron/ascorbate-induced lipid peroxidation. The pattern of free fatty acids showed a significant decrease of arachidonic and docosahexaenoic acid consequent to ET-1 treatment. The analysis of lipid composition showed a significant loss of phospholipids: among phospholipid species, sphingomyelin and phosphatidylethanolamine plasmalogen were particularly reduced by ET-1 treatment. The activity of membrane-bound Na+,K(+)-ATPase was also significantly reduced in synaptosomes obtained from ET-1 lesioned striata. Taken together these results indicate a significant modification of synaptosomal membrane of ET-1 treated rat striata, possibly due to a free radical mediated damage.

Animals↗