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Biomedical subjects

P Callard

Publications and source records attributed to P Callard.

At least 55 records · Page 3Linked to original sources
PubMed1995

Enhancement of mRNA in situ hybridization signal by microwave heating.

BACKGROUND: Optimization of in situ hybridization protocols is of real interest when trying to detect small amounts of mRNA or when using low concentrations of probes. To enhance the hybridization signal, we have developed a modification of an in situ hybridization (ISH) protocol with radiolabeled cRNA probes. The detailed protocol of ISH used for paraffin sections is also described. EXPERIMENTAL DESIGN: In microwave (MW) heating, the tissue sections are heated in a sodium citrate buffer (0.01 M, pH 6). The effects of the pretreatment with MW were studied on kidneys and adrenals of young rats and on human pathologic samples using [35S]-RNA probes complementary to the mRNAs of some components of the renin angiotensin system. RESULTS: The heating pretreatment with the MW permitted us to obtain an enhancement of the hybridization signal, especially when using low doses of radioactive probes. This enhancement could be evaluated to 60 to 120% by computer-assisted quantification of the signal. Furthermore, the histologic structures and the staining with toluidine blue were not impaired by the heating treatment. CONCLUSIONS: The enhancing effect of the hybridization signal obtained using MW allows shorter autoradiographic exposure times and/or the use of lower concentrations of radioactive probes for the detection of mRNA or the detection of mRNA expressed at the threshold of detection with usual protocols.

Adrenal Glands↗
PubMed1995

Expression of p53 protein related to the presence of human papillomavirus infection in precancer lesions of the larynx.

The aim of this study was to gain some insight into the relationship of human papillomavirus (HPV) infection to p53 expression and to some pathological parameters in precancerous lesions of the larynx. Formalin-fixed paraffin-embedded tissue sections containing human laryngeal precancerous lesions were screened for p53 protein by immunohistochemistry with the monoclonal antibody DO7 and for the presence of HPV infection by polymerase chain reaction with consensus primers directed against the E6 gene. The presence of p53 protein was detected in 31 of 57 specimens (54.4%) including 7 of 9 cases with mild dysplasia (78%), in 4 of 9 cases with moderate dysplasia (44%), and in 15 of 23 cases with severe dysplasia (65%). Of 16 samples with keratotic benign squamous metaplasia, 5 were also p53 positive (31%). Of 6 samples that were HPV positive, all were of type 16. Interestingly, 3 of the 6 HPV-positive samples were p53 negative. There was 1 HPV-positive case with strong p53 staining and 2 HPV-positive cases with minimal p53 staining. The 2 HPV-positive cases with minimal p53 staining had mild dysplasia. The HPV-positive case with strong p53 staining displayed severe dysplasia. Of 23 cases that were both HPV and p53 negative, 11 presented with keratosis and no dysplasia, 5 with moderate dysplasia, and 7 with severe dysplasia. Our data indicate that nuclear accumulation of p53 protein, presumably resulting from p53 gene mutation, may occur in HPV-infected epithelial tissues. On the other hand, there are many precancer lesions, some exhibiting moderate or severe dysplasia, that are both HPV negative and p53 unreactive, suggesting that alterations of genes other than the E6 oncogene and the p53 tumor suppressor gene play a role in early laryngeal carcinogenesis.

Adult↗
PubMed1994

Long-term renal tolerance of cyclosporin A treatment in adult idiopathic nephrotic syndrome. Collaborative Group of the Société de Néphrologie.

Repeat renal biopsies and serial serum creatinine measurements were done in 36 adults who were treated for steroid-dependent or -resistant idiopathic nephrotic syndrome with 5.54 +/- 0.81 mg/kg/day of cyclosporin A (CsA). Pre-CsA renal biopsy (RB1) had been carried out 11.6 +/- 12.2 months prior to CsA treatment. It showed minimal glomerular changes (MCD) in 22, and 1 to 16 glomeruli with lesions of focal segmental glomerulosclerosis (FSGS) per biopsy in 14. Pretreatment serum creatinine levels were (mumol/liter) 97.6 +/- 39.4 and were higher in FSGS (117.1 +/- 48.3) than in MCD (85.2 +/- 26.9; P < 0.04). Repeat biopsy (RB2) was done after 19.6 +/- 15.2 months (6 to 78) of CsA treatment. At this time, in 15 patients the minimal glomerular lesions observed on RB1 were unchanged, whereas in 7 patients lesions of FSGS were now visible. In patients with FSGS on RB1 and RB2, serum creatinine at the end of CsA treatment was 130.6 +/- 60.1 mumol/liter, significantly greater (P = 0.022) than the corresponding levels in the subset with MCD (87.3 +/- 24.8). The contrast between the remarkable stability of renal function in the patients with MCD and the worsening of renal function in the subgroup with FSGS was explained in the latter by an aggravation of renal histologic lesions, with a greater number of glomeruli with FSGS, of obsolescent glomeruli, and of interstitial fibrosis/infiltrates. This aggravation of the primary renal disease was observed in some cases where CsA had obtained partial or even complete remission. Few of the tubular lesions and of vascular changes were typical of CsA toxicity but rather suggested development of the primary renal disease. In contrast, although some increase in the degree of tubulointerstitial lesions was observed on RB2, the rating of such lesions was much less severe in patients whose renal biopsy showed persistently normal glomeruli after exposure to CsA. Overall, the most severe interstitial/vascular lesions were observed in patients treated with the highest CsA dosages, and the "cut-off" of dosage safety appeared to be 5.5 mg/kg/day. Two patients died during the study period. Long-term surveillance of the extant 34 patients showed that 8, all of whom had FSGS, evolved to end-stage renal failure due to progression of their primary renal disease after ending CsA treatment. Four patients were failures of CsA and returned to conventional therapy. CsA treatment was continued for 12 to 60 months in fourteen patients who achieved remission.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗
PubMed1994

[Significance of type III serum N-terminal peptide procollagen assay in chronic viral hepatitis C].

The aim of this study was to evaluate the relationship between the serum N-terminal peptide of type III procollagen (PIIINP), Knodell's score and the response to treatment in 79 patients with viral C chronic hepatitis. Liver biopsy and serum PIIINP was assessed in all patients. Serum PIIINP was correlated with Knodell'score (r = 0.60; P = 10(-4)). Correlation between serum alanine amino-transferase and Knodell'score was smaller than for PIIINP (r = 0.38; P = 0.02). Forty-nine patients were treated with interferon alpha. A second biopsy and serum PIIINP determination were performed one year after treatment discontinuation. Means of serum PIIINP and Knodell'score significantly decreased after treatment (P < 0.01; P < 0.03). Among non-responder patients, serum PIIINP was initially more elevated: 37.5 +/- 12.6 ng/mL versus 22.6 +/- 3.8 (P < 10(-3)). Knodell's score decreased only among responder patients (P < 0.01 vs P < 0.7). Positive and negative predictive value for the response to treatment, evaluated by aminotransferases normalization, of serum PIIINP level < or = 24 ng/mL were 0.6 and 0.9 respectively. These findings suggest that serum PIIINP is a relevant marker of activity in patients with viral C chronic hepatitis and that it might have a predictive value of response to treatment.

Adult↗
PubMed1993

Histologic aspects of pulmonary barotrauma in critically ill patients with acute respiratory failure.

OBJECTIVE: To describe histologically pulmonary barotrauma in mechanically ventilated patients with severe acute respiratory failure. DESIGN: Assessment of histologic pulmonary barotrauma. SETTING: A 14-bed surgical intensive care unit (SICU) PATIENTS: The lungs of 30 young critically ill patients (mean age 34 +/- 10 years) were histologically examined in the immediate post-mortem period. None of them were suspected of pre-existing emphysema. MEASUREMENTS AND RESULTS: Clinical events and ventilatory settings used during mechanical ventilation were compared with lung histology. Airspace enlargement, defined as the presence of either alveolar overdistension in aerated lung areas or intraparenchymal pseudocysts in nonaerated lung areas, was found in 26 of the 30 lungs examined (86%). Patients with severe airspace enlargement (2.6-40 mm internal diameter) had a significantly greater incidence of pneumothorax (8 versus 2, p < 0.05), were ventilated using higher peak airway pressures (56 +/- 18 cmH2O versus 44 +/- 10 cmH2O, p < 0.05) and tidal volumes (12 +/- 3 ml/kg versus 9 +/- 2 ml/kg, p < 0.05), were exposed significantly longer to toxic levels of oxygen (8.6 +/- 9.4 days versus 1.9 +/- 2 days at FIO2 > 0.6, p < 0.05) and lost more weight (6.3 +/- 9.2 kg versus 0.75 +/- 5.8 kg, p < 0.05) than patients with mild airspace enlargement (1-2.5 mm internal diameter). CONCLUSION: Underlying histologic lesions responsible for clinical lung barotrauma consist of pleural cysts, bronchiolar dilatation, alveolar overdistension and intraprenchymal pseudocysts. Mechanical ventilation appears to be an aggravating factor, particularly when high peak airway pressures and large tidal volumes are delivered by the ventilator.

Adult↗
PubMed1993

[Comparison of six potential serum markers of hepatic fibrosis in alcoholic disease of the liver].

The aim of this study was to compare 6 potential serum markers for hepatic fibrosis in patients with alcoholic liver disease. Ninety-three patients (50 +/- 11 years old, 62 males) with biopsy-proven alcoholic liver disease were included in the study. A liver biopsy and serum assays of type I, type III and type IV collagens, N-terminal peptide of type III procollagen, laminin (by radioimmunoassays) and apolipoprotein A1 (by nephelometry) were performed in all patients. A histological score of hepatic fibrosis was established. Alcoholic hepatitis lesions and perisinusoidal fibrosis were assessed separately. A significant correlation was found between the score of hepatic fibrosis and serum levels of type I collagen (r = 0.44, P < 10(-3)), type III collagen (r = 0.36, P < 10(-2)), N-terminal peptide of type III procollagen (r = 0.50, P < 10(-3)), type IV collagen (r = 0.44, P < 10(-3)), laminin (r = 0.50, P < 10(-3)), and apolipoprotein A1 (r = 0.21, P < 0.05). After adjustment for the presence of lesions of alcoholic hepatitis and perisinusoidal fibrosis (partial correlation), serum levels of type I collagen, type III collagen, N-terminal peptide of type III procollagen, type IV collagen, and laminin remained significantly correlated with the score of hepatic fibrosis; in contrast, correlation with serum apolipoprotein A1 was no longer significant. Serum levels of N-terminal peptide of type III procollagen, type IV collagen and laminin were significantly higher in patients with perisinusoidal fibrosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Acute reversible renal failure with macroscopic haematuria in IgA nephropathy.

Macroscopic haematuria is common in IgA nephropathy, but its significance and influence on prognosis remains uncertain. We compared the clinical and pathological features of 11 adult patients with primary IgA nephropathy who had had a renal biopsy during or shortly after a bleeding episode. Six patients developed transient acute renal failure (ARF) (group 1) and five did not (group 2). Patients of group 1 had a higher percentage of tubular red-blood-cell (RBC) casts (P < 0.05) and of glomerular crescents (P < 0.001). However, crescents were focal and involved less than 50% of glomeruli. Acute tubular necrosis was only present in patients of group 1, and ARF was attributed to the acute tubular changes rather than to the glomerular lesions. Despite a prolonged duration of ARF (mean: 38 days), further outcome did not differ in patients of both groups. We suggest that acute tubular damage and/or tubular obstruction by RBC casts should be considered in any patient who develops ARF soon after a haematuric episode.

Acute Kidney Injury↗
PubMed1993

Systemic lupus erythematosus and chronic intestinal pseudoobstruction.

We describe the first case of a patient with systemic lupus erythematosus in which clinical and radiological features, small bowel manometry and histological studies were consistent with the diagnosis of chronic intestinal pseudoobstruction. Our patient developed a fatal form of lupus with cerebral angiitis and tubulointerstitial lupus nephritis, with no sign of progressive systemic sclerosis or dermatopolymyositis. Postmortem examination confirmed the presence of an extensive fibrotic process in the muscularis layers, whereas the muscularis mucosae and the innervation of the digestive wall were spared.

Adult↗
PubMed1992

Lymphocytic sialadenitis of Sjögren's syndrome associated with chronic hepatitis C virus liver disease.

Viral infection has often been suggested as a possible cause of Sjögren's syndrome or chronic lymphocytic sialadenitis, and Epstein-Barr virus has been found in the salivary glands of patients with this condition. After we had noted Sjögren's syndrome in several patients infected with hepatitis C virus (HCV), a virus also excreted in saliva, we set up a prospective study to investigate the association of chronic lymphocytic sialadenitis, with or without symptoms, to chronic HCV liver disease. The histological appearances of labial salivary glands in patients with proven HCV hepatitis or cirrhosis were compared with those in dead controls. Histological changes characteristic of Sjögren's syndrome were significantly more common in HCV-infected patients (16 of 28, 57%) compared with controls (1 of 20, 5%). Focal lymphocytic sialadenitis characteristic of Sjögren's syndrome (though only 10 patients had xerostomia and none complained of xerophthalmia) appears to be common in patients with chronic HCV liver disease; if this association is confirmed, identification of the underlying mechanism may improve our understanding of both disorders.

Adult↗
PubMed1992

Treatment of severe alcoholic hepatitis by infusion of insulin and glucagon: a multicenter sequential trial.

Severe alcoholic hepatitis is still a therapeutic challenge. It has been recently advocated that a 3-wk infusion with insulin and glucagon reduces its short-term mortality rate. A multicenter, randomized, single-blind, sequential trial was designed to compare this treatment with placebo. The triangular boundary was defined with alpha = 0.05, beta = 0.10 and estimated survival at 4 wk of 50% with placebo, 75% with treatment. Patients with biopsy-proven severe alcoholic hepatitis (presence of one or more of three criteria: encephalopathy, prothrombin activity less than or equal to 50%, bilirubinemia greater than or equal to 100 mumol/L) were randomized into two groups; one treatment group received an infusion (12 hr/day) of an association of insulin (30 IU) and glucagon (3 mg), and a control group received an infusion of glucose. Treatments were administered during a 3-wk period, and the mortality rate was noted at 4 wk. The decision to discontinue the trial was reached on the basis of results from the first 44 patients. Overall results were assessed in the 72 patients included at the time of this decision (treatment group: n = 37; control group: n = 35). Fifty-three patients had cirrhosis. No significant differences were noted between the two groups at inclusion on the basis of clinical, laboratory and histological criteria. The mortality rate was not significantly different in the two groups; 10 patients (27%) in the treatment group and 5 patients (14%) in the control group died. Causes of death were similar in the two groups and consisted primarily of gastrointestinal hemorrhage, hepatic failure and infectious events.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Serum type I collagen and N-terminal peptide of type III procollagen in patients with alcoholic liver disease: relationship to liver histology.

This study compared, in patients with alcoholic liver disease, the serum concentration of N-terminal peptide of type III procollagen and of a novel serum marker, type I collagen, with liver histological data and assessed the role of these markers in the diagnosis and follow-up of liver changes. Ninety-six patients (mean age 51 years, 61 men and 35 women) were included. All had alcoholic liver disease diagnosed on usual clinical, biochemical, and histological criteria. Two histological scores, one for alcoholic hepatitis and one for fibrosis, were established. Serum N-terminal peptide of type III procollagen and type I collagen were assayed by liquid phase radioimmunoassay. Significant correlations between serum type I collagen and score of fibrosis (r = 0.34, p less than 0.001) and between serum N-terminal peptide of type III procollagen and score of alcoholic hepatitis (r = 0.60, p less than 0.0001) were noted. There was no significant correlation between serum aminotransferases and the score of alcoholic hepatitis. In 25 patients with alcoholic hepatitis reassessed between 3 and 6 months, serum N-terminal peptide of type III procollagen significantly decreased (p less than 0.05) as did the score of alcoholic hepatitis, but serum type I collagen and the score of fibrosis were not modified. These serum markers of collagen metabolism could be useful for the assessment and follow-up in patients with alcoholic liver disease.

Adult↗
PubMed1992

High-resolution CT of parenchymal lung disease: precise correlation with histologic findings.

To provide a precise correlation between high-resolution computed tomographic (CT) findings and histologic studies of various parenchymal lung diseases, 20 fixed and inflated lungs were studied as follows: (a) Every lung was cut at the corresponding CT level into 1.5-mm-thick sections, (b) selected slices were cut into small blocks to prepare histologic slides, (c) each slide was photographed, and (d) the image of the entire lung section was reconstituted with the enlarged photographs (assembled as in a jigsaw puzzle). Results obtained in cases of normal lungs, pulmonary edema, alveolitis, hypersensitivity pneumonitis, emphysema, Pneumocystis carinii pneumonia, silicosis-asbestosis, and idiopathic pulmonary fibrosis demonstrated the method to be accurate in correlating high-resolution CT findings and the corresponding histologic data.

Alveolitis, Extrinsic Allergic↗
PubMed1992

Minimal change nephrotic syndrome revealing solid tumors.

In 2 patients with the nephrotic syndrome, unsuspected solid tumors were found. One was a small cell lung carcinoma, accompanied with the syndrome of inappropriate ADH secretion. The other was a cancer of the breast with lymph node and bone metastases. In both, renal biopsy showed minimal change disease without immune complex deposits. There are only 14 other reported cases of paraneoplastic lipoid nephrosis complicating solid tumors. Such cases lead to the discussion on the respective roles of tumor cell gene product(s) inducing proteinuria and of lymphokine secretion by lymphocytes directed against the tumor itself. Cancer should be considered as a possible etiology of the minimal change nephrotic syndrome in the adult.

Breast Neoplasms↗