Search PubMed⌕ Search

Biomedical subjects

M Candela

Publications and source records attributed to M Candela.

At least 37 records · Page 2Linked to original sources
PubMed1996

Hepatitis C virus infection and mixed cryoglobulinaemia: assessment of HCV RNA copy numbers in supernatant, cryoprecipitate and non-liver cells.

The aim of this study was to characterize hepatitis C virus (HCV) infection in patients with mixed cryoglobulinaemia (MC). The HCV RNA copy number was assayed in clinical specimens from 15 consecutive patients with MC and HCV infection. Absolute quantification of HCV RNA molecules was performed using a competitive reverse transcription-polymerase chain reaction (cRT-PCR). Specific HCV RNA sequences were detected and quantified in plasma samples from all patients (mean HCV RNA copy number 4.9 x 10(6) ml-1 plasma). A high concentration of HCV RNA molecules was detected in the cryoprecipitates of eight of the 15 patients, who had a cryoprecipitate/supernatant ratio higher than 3.0 (range 3.60 to 186.80): in the remaining seven patients this ratio was close to or lower than 1.0 (range 0.13 to 1.60). Quantitative analysis of HCV RNA molecules in cells other than hepatocytes (i.e. peripheral blood mononuclear cells (PBMCs) and bone marrow cells (BMCs), in which the HCV replicative intermediate was detected using strand specific RT-PCR, demonstrated that infection is detectable in nearly 60% of these extrahepatic cells. Quantitative analysis of HCV RNA in PBMCs and BMCs revealed low levels of viral nucleic acids.

Aged↗
PubMed1996

Neocytoapheresis in the treatment of polycythemia vera.

In absence of thrombocytosis, periodic bloodlettings represent the elective therapy of polycythemia vera. In the present study we tested if neocytoapheresis, a method able to remove large quantities of younger, and then bigger red cells could represent an alternative therapeutic choice in these patients. We found that the employment of neocytoapheresis produced a remarkable delay in the time of procedures with a mean interval of 100 +/- 55 days. The mean value of hematocrit before neocytopheresis is resulted statistically different in comparison with the hematocrit after the procedure (p = 0.0001). The reticulocyte count is resulted higher in apheresis product in comparison with the blood control measured before procedure (p = 0.0001). In the same way, the mean corpuscular volume in the collection bags was higher than the volume measured before neocytoapheresis (p = 0.0095). We did not find any variation about the mean values of white blood cells and platelets before and after neocytoapheresis in the patients examined. These preliminary data seem to underline a better withdrawal of big size cells by this technique suggesting the efficacy of neocytoapheresis in the treatment of polycythemia vera.

Blood Cell Count↗
PubMed1996

[Neuro-SLE. Models of its clinical expression].

In this paper we considered different models concerning the clinical expression of neuropsychiatric involvement in course of systemic lupus erythematosus (SLE). These models describe pathological conditions as multifocal cerebropathy, transverse myelitis, peripheral neuropathy and panic attacks. We have chosen these cases as clinical example of different pathogenic mechanisms responsible of CNS-lupus, as hypercoagulation due to antiphospholipid syndrome, immune-complex vasculitis, complement-mediated autoantibody damage and antibody-induced cytotoxicity. The prevalence of neuropsychiatric manifestations in 122 SLE patients is also reported. Finally, the paper reports some guidelines about diagnostic and therapeutic behaviour in course of CNS-lupus.

Adolescent↗
PubMed1994

Active hepatitis C virus infection in bone marrow and peripheral blood mononuclear cells from patients with mixed cryoglobulinaemia.

The presence of hepatitis C virus (HCV) genomic sequences was checked in plasma, liver, peripheral blood mononuclear cells (PBMC) and bone marrow cells from 11 patients with mixed cryoglobulinaemia positive for anti-HCV antibodies, and from 11 patients with chronic HCV hepatitis without serological evidence of cryoglobulinaemia. HCV RNA sequences were demonstrated by reverse transcription polymerase chain reaction in seven plasma samples, in six PBMC samples, and in seven bone marrow cell samples from the 11 cryoglobulinaemic subjects; otherwise, viral specific nucleic acids were detected in 10 plasma samples, in one PBMC sample, and in two bone marrow cell samples from the 11 patients with chronic hepatitis. The HCV replicative intermediate was evidenced in four of the six PBMC and in five of the seven bone marrow aspirate HCV RNA-positive samples. Analysis of subpopulations isolated from bone marrow and peripheral blood samples showed HCV RNA sequences in mononuclear cells belonging either the CD2+ subset or to the CD19+ subpopulation or to the adherent cells. Finally, we compared the nucleotide sequences of a large portion (-270 to -59) of the HCV 5'-untranslated region from five patients with mixed cryoglobulinaemia and from seven patients with chronic hepatitis without cryoglobulinaemia; the degree of heterogeneity, compared with the prototype HCV sequence, was similar in both groups. These findings from two groups of HCV-infected patients indicate that transient or permanent active HCV infection of bone marrow and PBMC is frequent in anti-HCV-positive patients with mixed cryoglobulinaemia, and suggest that extra-hepatic infection may play a major role in influencing the pathophysiology of this infection as well as the viral persistence.

Aged↗
PubMed1994

Presence of hepatitis C virus (HCV) genomic RNA and viral replicative intermediates in bone marrow and peripheral blood mononuclear cells from HCV-infected patients.

The cellular tropism of hepatitis C virus (HCV) was studied in vivo in samples from patients with persistent HCV infection. Plasma, liver, peripheral blood mononuclear cell (PBMC), and bone marrow cell (BMC) samples from 15 subjects positive for anti-HCV antibodies were tested for the presence of HCV RNA sequences by reverse transcription PCR. Virus-specific RNA sequences were found to be present in liver samples from all subjects (100%), in plasma samples from 13 of 15 patients (86.7%), in PBMC samples from 3 patients (20%), and in BMC samples from 9 (60%) of the 15 anti-HCV-positive patients enrolled in this study. The presence of the molecular intermediate of HCV replication (the negative-stranded HCV RNA) was evident in the two of the three PBMC and in five of the nine BMC HCV RNA-positive samples. Finally, we studied the nucleotide sequence of a large portion (-270 to -59) of the 5'untranslated region of HCV amplified from plasma samples of 12 of the 15 patients with and without HCV in BMCs; the degree of heterogeneity compared with the prototype HCV sequence was similar in both groups. The data principally indicate that HCV infection of PBMCs and BMCs is frequent in persistently infected patients, as shown by the occurrence of positive- and negative-stranded HCV RNA, thus suggesting the possibility of extrahepatic replication of HCV.

Adult↗
PubMed1994

Prognostic significance of basement membrane antigens and of soluble interleukin 2 receptor serum concentrations in heart transplant rejection.

Endomyocardial biopsy is still considered the only reliable method for diagnosing acute rejection. However, because of its invasive nature, this procedure cannot be performed on a daily basis. Therefore, for the noninvasive monitoring of transplanted patients, we tested the sensitivity of serum levels of basement membrane antigens, type IV collagen fragment NC1 and laminin fragment P1 (LP1), of antibodies against laminin and type IV collagen, and of soluble interleukin 2 receptor (sIL2R). In 17 patients who underwent heart transplantation no correlation was found between the degree of rejection and the levels of antibodies to type IV collagen and laminin. Serum laminin P1 and sIL2-R values were found increased in all the study groups even in absence of rejection; however, sIL2R levels were higher in patients with more severe rejection. NC1 levels were found significantly higher in patients with mild or moderate rejection than in those with no rejection or in controls. These preliminary data suggest a possible predictive role of basement membrane antigens in cardiac rejection, but further studies in a larger group of transplanted patients are needed.

Adolescent↗
PubMed1993

Fibroblast growth factor increases TNF alpha-mediated prostaglandin E2 production and TNF alpha receptor expression in human fibroblasts.

To examine the possible role of basic fibroblast growth factor (FGF) in regulating the effects of TNF alpha, we tested the effect of FGF on TNF alpha-mediated PGE2 production and TNF alpha receptor expression in human fibroblasts. We found that, while FGF alone had no effect on PGE2 production, it enhanced the amount of PGE2 produced in response to TNF alpha between 3 and 11-fold. FGF stimulated TNF alpha-induced PGE2 production independent of potential TNF alpha-mediated IL-1 production, as neither anti-IL-1 mAbs nor IL-1 receptor antagonist protein (IRAP) inhibited TNF alpha induced-PGE2 production or the stimulatory effect of FGF. A one minute exposure of cells to FGF prior to removal was sufficient to significantly enhance TNF alpha-induced PGE2 production; the maximal FGF effect was reached after a 6 h preincubation. We also found that FGF significantly enhanced TNF alpha receptor expression. Untreated fibroblasts expressed approximately 3,900 receptors/cell, while cells treated with FGF for 6 h expressed approximately 9,500 receptors/cell, a 2.4-fold increase in receptor number; there was no apparent change in affinity for TNF alpha (Kd 3.8 x 10(-11) M). The FGF-mediated increase in TNF alpha receptor expression and TNF alpha-mediated PGE2 production could be abolished by FGF mAbs, indicating a specific FGF effect. These results show that FGF increases TNF alpha receptor expression and suggest that this may account, at least in part, for the ability of FGF to enhance TNF alpha-mediated PGE2 production in human fibroblasts.

Antibodies, Monoclonal↗
PubMed1993

Immunohistochemical localization of intracellular and extracellular associated TGF beta in the skin of patients with systemic sclerosis (scleroderma) and primary Raynaud's phenomenon.

We have investigated the distribution of TGF beta using antibodies specific for its intracellular and extracellular forms in full-thickness biopsies of patients with SSc, primary Raynaud's phenomenon (PRP), systemic lupus erythematosus (SLE), and from normal subjects. Nine of 11 SSc biopsies demonstrated intracellular TGF beta in endothelial cells while only 6 exhibited extracellular TGF beta. Endothelial cells in skin biopsies of all PRP patients displayed both intracellular and extracellular TGF beta. All other control biopsies were negative. In patients with PRP, some positively staining fibroblasts were found scattered throughout the dermis. Lastly, extracellular TGF beta was localized in the papillary dermis of PRP and SSc biopsies and in all the dermal layers of SLE patients. No significant staining of TGF beta was observed in the endothelial cells, fibroblasts, or in the extracellular matrix of the majority of biopsies from normal subjects. These data suggest that TGF beta may be one of the cytokines involved in the early stages of pathogenesis of SSc, and that endothelial cells in SSc and PRP may be a source and/or a target of TGF beta.

Aged↗
PubMed1993

[Influence of sex, age, and profession on transient work disability at a health center].

OBJECTIVE: To analyse whether the variables of gender, age and type of job of those in full-time work affect short-term unfitness for work (SUW) in a study undertaken within our health area. DESIGN: A prospective and retrospective study of all the SUW. SETTING: Primary Care. An urban Health Centre. PARTICIPANTS: Those people with full-time jobs registered at the Centre. MAIN MEASUREMENTS AND RESULTS: The entire 1098 certificates of SUW issued in 1990 were processed. The population pyramid and job distribution among those in full-time work was obtained by a random sample of 5% of the active population. When time off for maternity (TOM) was excluded, women accounted for 44.8% of SUW and men 55.2%. There were no significant differences with the percentages these figures represent for the active population as a whole. The number of SUW per 100 people in work was 15.9 for men and 21.5 and 17.4 for women (including and excluding TOM, respectively). The average length of SUW, excluding maternity, was 27.06 days for men and 26.8 for women. On the question of age, those under 19 and over 40 contributed least to the SUW percentage. Additionally, those under 19 and over 60 were the proportions of the population least prone to SUW. On the question of type of job, we found a higher contribution to absenteeism than expected within Groups 3 and 4 and less in Groups 0/1, 5 and 7/8/9. The longest average length of time for SUW was in Group X (84.2 days/SUW). CONCLUSIONS: Excluding TOM, gender does not appear to be a variable that affects SUW. Age group and type of job are variables affecting SUW. It will be necessary to undertake research into whether there are additional social or labour factors which might explain.

Absenteeism↗
PubMed1992

Antibodies to mycobacterial 65 kDa heat shock protein in systemic sclerosis (scleroderma).

It has been reported that immunity to the 65 kDa heat shock protein of Mycobacterium tuberculosis (MT-hsp65) not only accompanies rheumatoid arthritis (RA), but may also be characteristic of chronic inflammation. We now report serum antibodies to MT-hsp65 in 47% of systemic sclerosis (SSc), 38% of primary Raynaud's phenomenon (PRP) and 5% of systemic lupus erythematosus (SLE). Antibody levels were higher in patients with active or progressive SSc and correlated with the degree of skin fibrosis. Thus, immunity to MT-hsp65 appears in SSc and is not limited to RA. However, it does show some degree of specificity beyond chronic inflammation: PRP patients have a higher reactivity than do SLE patients.

Adolescent↗
PubMed1991

Sphingosine synergistically stimulates tumor necrosis factor alpha-induced prostaglandin E2 production in human fibroblasts.

Sphingosine is a biologically active derivative of sphingomyelin. It affects diverse cellular functions and its mechanism(s) of action is poorly defined. Tumor necrosis factor alpha (TNF alpha) has recently been shown to rapidly induce sphingomyelin turnover, implicating this metabolic pathway in TNF alpha signal transduction. Because TNF alpha is known to induce prostaglandin E2 (PGE2) production in human fibroblasts, we tested the effect of sphingosine on TNF alpha-induced PGE2 production. We found that sphingosine enhanced TNF alpha-induced PGE2 production by as much as 18-fold over TNF alpha alone. Sphingosine appeared to stimulate TNF alpha-induced PGE2 production independent of TNF alpha-mediated interleukin 1 (IL-1) production, because anti-IL-1 antibodies and IL-1 receptor antagonist protein (IRAP) did not inhibit TNF alpha-induced PGE2 production or the stimulatory effect of sphingosine. TNF alpha stimulated PGE2 production to the same degree in normal and protein kinase C (PKC) downregulated cells in the presence and absence of sphingosine, indicating that neither TNF alpha nor sphingosine require active PKC to elicit their respective effects. The sphingosine analogues stearylamine and stearoyl-D-sphingosine had little or no effect on TNF alpha-mediated PGE2 production, supporting a specific role for sphingosine in the activation process. Short-term (1 min) exposure of cells to sphingosine dramatically increased TNF alpha-induced PGE2 production. A potential mechanism by which sphingosine could increase TNF alpha-induced PGE2 production involves enhancement of phospholipase A2 (PLA2) and/or cyclooxygenase (Cox) activity, the rate-limiting enzymes in PGE2 production. We found that both TNF alpha and sphingosine alone enhanced these enzymatic activities, and that sphingosine additively increased the effect of TNF alpha on phospholipase A2 activity. It appears that sphingosine affects TNF alpha-induced PGE2 production via a mechanism that is independent of PKC involvement, and that sphingosine may function as an endogenous second messenger capable of modulating the responsiveness of the cell to external stimuli.

Cell Line↗
PubMed1991

Oropharyngeal and esophageal function in scleroderma.

Fifty-one patients with systemic sclerosis (scleroderma) underwent videofluoroscopy during barium swallow to evaluate the incidence of oropharyngeal deglutition abnormalities and to correlate the radiologic patterns of esophageal motility abnormalities with patients' clinical features. Thirteen patients (26%) showed swallowing dysfunction, (e.g., oral leakage, retention, penetration, mild or moderate aspiration, and upper esophageal sphincter incoordination). These dysfunctions were more severe in patients with prominent esophageal dysmotility. Normal esophageal motility was not associated with swallowing alterations. Patients with an oropharyngeal disorder had a higher incidence of pulmonary disease. The clinical picture of the above-mentioned 13 patients was more severe, based on the duration of Raynaud's phenomenon and duration of skin sclerosis. Patients with primary Raynaud's phenomenon had no oral or esophageal abnormalities. The esophageal phase of swallowing was abnormal in 80% of the patients with scleroderma. Esophageal dysfunction, therefore, seems to be frequent in the early stages of the disease. However, patients with advanced or extensive disease may have normal esophageal function.

Adult↗
PubMed1991

Antibodies to mouse laminin in patients with systemic sclerosis (scleroderma) recognize galactosyl (alpha 1-3)-galactose epitopes.

Employing radioimmunoinhibition assays with distinct oligosaccharides as inhibitors, this study demonstrates that the epitope recognized on mouse laminin by sera from patients with systemic sclerosis (scleroderma) is a terminal galactosyl (alpha 1-3)-galactose disaccharide. The reaction with this alpha-digalactose was further confirmed when the sera were tested in radioimmunoassay (RIA) binding assay and in ELISA with synthetic galactose alpha 1-3 galactose coupled to human serum albumin. The circulating antibody appeared restricted to the IgG class and mostly to the subclass IgG3 and IgG4. Antibodies with the same specificity can be found in patients with American cutaneous leishmaniasis and Chagas disease; however, whilst in these diseases the antibody production is triggered by antigenic determinants present on the surface of the parasites, the events eliciting their appearance in systemic sclerosis are unknown.

Disaccharides↗
PubMed1990

[Correlation between the radiologic study of deglutition and the clinical picture in systemic sclerosis (scleroderma)].

Fifty-one patients with systemic sclerosis (scleroderma) were studied by means of videofluoroscopy in order to evaluate the abnormalities in the oropharyngeal and esophageal phases of deglutition and to correlate the radiological patterns with the clinical features of the disease. Thirteen patients (25.5%) exhibited swallowing disorders such as oral leakage, retention, penetration, mild or moderate aspiration and abnormal upper esophageal sphincter behavior. These dysfunctions were more evident in patients with esophageal motility abnormalities. A normal radiological pattern in the esophagus was not associated with swallowing alterations. Remarkably, patients with oral-pharyngeal disorders had a higher incidence of lung diseases. Forty-five patients (88%) exhibited disorders of the esophageal phase of deglutition, such as mild or severe motility abnormalities or hiatal hernia, gastro-esophageal reflux, reflux esophagitis, and stricture. Radiological findings in the esophagus can be abnormal in the early stages of the disease. On the other hand, the radiological pattern of esophageal motility can be occasionally negative in advanced or extensive disease. This indicates a discrepancy between clinical symptoms and radiological picture of the esophagus. The radiological examination of the oral-pharyngeal and esophageal phases of deglutition is important in patients with scleroderma in order to evaluate visceral involvement, motility disorders, and risk of aspiration. Such radiological information can be useful in preventing esophagitis and pulmonary complications.

Adult↗
PubMed1989

Clinical significance of the histomorphometric evaluation of diabetic microangiopathy in the oral mucosa.

Several structural parameters of the capillary vessels were measured in the oral mucosa of patients with diabetes mellitus of type 1 (D.1) and of type 2 (D.2), and of control cases (C), by means of an image analyser in histological sections of routinely processed biopsies. The studied parameters included: a) capillary wall thickness; b) capillary diameter; c) the ratio of capillary wall thickness and diameter; d) capillary wall area; e) capillary area; f) the ratio of capillary wall area and capillary area; g) density of capillary vessels in the lamina propria; h) density of endothelial cells; i) endothelial nuclear area. Clinical and laboratory parameters were also evaluated (duration of the disease, systolic and diastolic blood pressure levels, glycemia, glycosylated haemoglobin, glycosylated albumin, fructosamines, apolipoproteins A1 and B), in order to assess whether a relationship exists with the morphometric parameters studied. Statistically significant differences, at the level of p less than 0.05, were found in the following morphometric parameters between controls and each group of diabetic patients: mean and standard deviation of capillary wall thickness, mean capillary wall area, mean ratio of the capillary wall area and capillary area. A reduction in the capillary density, i.e. the number of capillary vessels per mm2 of lamina propria, was also observed in diabetic patients with respect to the control group, although it was not statistically significant (C vs. D.1: p less than 0.21; C vs. D.2: p less than 0.10).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMedDate not supplied

[The temporary work incapacities of professional administrative workers and nurses].

We show the results of a retrospective study designed to assess the features of transient job disability (TJD) episodes of workers from two groups (clerks and nurses) from an urban health basic zone with 24,536 inhabitants, out of which 6,009 were active workers registered in social security databases. Population pyramid and job distribution in active workers were obtained from a random sample including 5% of the active population, out of which 17% were clerks and 5.54% nurses. There were 1098 TJD episodes in 1990; 32.4% of them involved clerks and 8.3% nurses. The mean length of episodes was 28.2 days in nurses and 27.8 days among clerks, compared to 32.4 days in the active population. These differences remained (p < 0.001) even after excluding TJD episodes of pregnant women, in whose case the mean length of episodes involving male or female workers was the same. The percentage of TJD episodes was higher among female nurses and clerks, than among the whole female population. Influenza was responsible for 20.5% of TJD in clerks against 14.3% among nurses and 14.8% in the whole active population. We conclude that, in the groups studied, the rate of job absenteeism was higher than in the whole population, and higher in female than in males. However, in the whole population, there were no differences in TJD rates between males and females. We discuss that several factors other than illness may explain the differences among groups.

Absenteeism↗