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M Robert

Publications and source records attributed to M Robert.

At least 109 records · Page 6Linked to original sources
PubMed1995

Localization of the N-terminal and C-terminal ends of triadin with respect to the sarcoplasmic reticulum membrane of rabbit skeletal muscle.

Antibodies were raised against synthetic peptides corresponding to the N-terminal (residues 2-17) and C-terminal (residues 691-706) ends of rabbit skeletal muscle triadin, a 95 kDa protein located in the sarcoplasmic reticulum membrane at the triad junction. The specificity of the antibodies generated was tested by ELISA and Western blot analysis. These tests demonstrated the ability of the antibodies to react specifically with the proteins. The anti-N-terminus antibodies bound to sarcoplasmic reticulum vesicles, indicating that the N-terminal end of the membrane-embedded triadin is exposed on the cytoplasmic side of the vesicles. In contrast, the anti-C-terminus antibodies were able to react with sarcoplasmic reticulum vesicles only after permeabilization of the vesicles with a detergent, indicating that the C-terminal end is exposed on the luminal side of the vesicles. These immunological data were complemented by proteolysis experiments using carboxypeptidases and endoproteinase Arg C. A mixture of carboxypeptidases A, B and Y was used to induce degradation of the C-terminal end of triadin in sarcoplasmic reticulum vesicles. This degradation, and a concomitant loss of reactivity of the anti-C-terminus antibodies in Western blots, was observed only when the vesicles were permeabilized, providing further evidence for the luminal localization of the C-terminal end of triadin. Treatment of sarcoplasmic reticulum vesicles with endoproteinase Arg C resulted in the removal of the N-terminal end of triadin, probably due to cleavage after Arg-34. This is a further indication of the cytoplasmic localization of the N-terminal end of triadin (and of its first 34 amino acids). When the proteolysis with endoproteinase Arg C was carried out with permeabilized vesicles, the cleavage occurred after Arg-141 or Arg-157, indicating that at least one of these residues is luminal.

Amino Acid Sequence↗
PubMed1995

Perforin and granzyme B. Cytolytic proteins up-regulated during rejection of rat small intestine allografts.

Perforin and granzyme B are 2 cytolytic proteins specific to activated killer cells, particularly CTL. We have studied the mRNA expression of these 2 proteins by a reverse transcriptase polymerase chain reaction method in a unidirectional model of rat small intestine transplant rejection. The allograft group consisted of Lewis x Brown Norway F1 donors into Lewis recipients. The isograft controls were Lewis donors into Lewis recipients. Grafts were placed heterotopically and no immunosuppression was given. Five animals in each group were killed at postoperative days (POD) 3, 5, 7, 8, 9, 10, 12, and 14. mRNA was extracted and a semiquantitative reverse transcriptase polymerase chain reaction was performed. For the semiquantitative analysis, we compared scintillation counts from excised bands. Results were expressed as a percent activity compared with beta-actin. From the same tissue samples, a histologic evaluation was made and rejection was graded according to severity. The isograft controls showed no evidence of histologic rejection and a very low expression of mRNA for perforin and granzyme B from POD 3-14. In contrast, the allograft group began to show histologic evidence of mild rejection on POD 5. By day 7, rejection was moderately severe and associated with a significant up-regulation of perforin and granzyme B in the allografts compared with the controls (P < 0.01), which persisted through POD 14. Peak expression for perforin and granzyme B was on POD 10 and 8, respectively. We conclude that the up-regulation of perforin and granzyme B in rat small intestine transplant allografts is a useful marker of clinically important rejection.

Animals↗
PubMed1995

The management of upper urinary tract calculi by piezoelectric extracorporeal shock wave lithotripsy in spinal cord injury patients.

From May 1988 to September 1994, 15 spinal cord injury patients were treated by piezoelectric extracorporeal shock wave lithotripsy. Aged from 23 to 71 years (mean = 39), they presented with a total of 23 stones, of which 18 were located in the calyces, three in the renal pelvis and two in the proximal ureter. The maximum dimensions of calculi varied from 5 to 35 mm (mean = 11). Patients were placed in a dorsal decubitus position during the sessions, three being sedated with diazepam, while the other 12 remained unsedated. All were treated routinely with systemic antibiotics. Auxiliary procedures consisted of two pyelocalyceal flushings, three double J ureteral stenting and three ureteroscopies with fragment removal with a Dormia basket. No episode of autonomic dysreflexia was observed. Short term side effects were limited to a few cases of gross haematuria which regressed spontaneously. Overall, eight successes (53%), and seven failures (47%), were registered. Of the failures, one was the result of a partial fragmentation, while six were related to intrarenal retention of residual fragments resulting in four cases in rapid recurrences. Extracorporeal shock wave lithotripsy can be easily applied to spinal cord injury patients. Its usefulness and limitations need to be well understood and a global consideration must be applied to the prevention and early detection of the upper urinary calculi in this exposed population of patients.

Adult↗
PubMed1995

Sperm motility inhibitor from human seminal plasma: association with semen coagulum.

Human seminal plasma contains a sperm motility inhibitor (SPMI) originating from the seminal vesicles as a 52 kDa precursor form that is rapidly degraded by prostatic proteases after ejaculation. In this study, the distribution of SPMI biological activity and antigens was analysed in chemically induced, as well as naturally occurring, arrest of semen liquefaction. SPMI activity was detected exclusively in the coagulated semen fraction at 2200 +/- 560 IU, whereas total seminal plasma proteins separated more evenly between soluble and coagulated components (91 +/- 19 and 65 +/- 18 mg, respectively). An SPMI antiserum recognized different forms of SPMI precursors at 52, 38, 35, 33 and 20 kDa in the coagulum while the soluble protein fraction contained only one major immunoreactive band at 15 kDa. High levels of SPMI activity (1500 +/- 180 IU/ml) together with high molecular mass forms of SPMI precursor and low sperm motility (26%) were detected in semen samples that failed to liquefy spontaneously at room temperature. Addition of prostatic secretions to the non-liquefying samples caused a decrease of SPMI activity (330 +/- 17 IU/ml) and transformed the SPMI precursor into low molecular mass forms (14-22 kDa) with a concomitant increase in sperm motility to 49%. The results suggest that SPMI is highly associated with the seminal coagulum components as very active forms that may adversely affect sperm motility when not properly processed after ejaculation.

Adult↗
PubMed1995

Percentage area density of epithelial and mesenchymal components in benign prostatic hyperplasia: comparison of results between single biopsy, multiple biopsies and multiple tissue specimens.

OBJECTIVE: To determine whether histological analysis of six multiple random biopsies of the gland or analysis of only one biopsy provides a good estimate of the different components of the hyperplastic gland compared with the results obtained from tissue specimens (reference values). MATERIALS AND METHODS: The various components of prostate tissue obtained from 30 men undergoing suprapubic adenomectomy were investigated. The histological analysis was performed on multiple tissue specimens reflecting adenoma (reference values) and on one and six biopsies performed at random on the enucleated material of the hyperplastic gland. Immunohisto chemistry using anti-actin as a label of smooth muscle and specific histological staining coupled with computer-assisted quantitative morphometric analysis was used to ascertain the histological composition of the prostate. RESULTS: The mean ( +/- SD) area densities obtained from tissue specimens were 34.1 +/- 5%, 32.4 +/- 6.9%, 17.6 +/- 4.5% and 15.9 +/- 5.5% of smooth muscular and fibrous tissue, and epithelium and glandular lumen, respectively. The mean ratio of stromal to epithelial hyperplasia averaged 4.05 +/- 1.73. Both one and six biopsies gave a good estimate of fibrous tissue and glandular epithelium, but the percentage of smooth muscles was overestimated and the percentage of glandular lumen was underestimated. There was a significant relation between the prostate area densities of glandular epithelium (r = -0.41, P < 0.05), the percentage area density of prostate smooth muscle (r = 0.43, P < 0.05), and the weight of enucleated adenoma. No correlation was found with prostate-specific antigen (PSA). CONCLUSION: It seems feasible to propose medical treatment of benign prostatic hyperplasia (BPH) based on the histological composition of the prostate gland. One biopsy, reflecting in good proportions the nature of the adenoma, would be used to provide insight into the pathogenesis and therapy of BPH.

Aged↗
PubMed1995

In situ piezoelectric extracorporeal shock wave lithotripsy of ureteric stones.

OBJECTIVE: To evaluate the efficacy of the EDAP LT 02 lithotripter for the in situ treatment of ureteric calculi. PATIENTS AND METHODS: One hundred consecutive patients presenting with ureteric calculi were treated with in situ piezoelectric extracorporeal shock wave lithotripsy (ESWL) using the EDAP LT 02 lithotripter. There were 49 patients with upper, nine with mid and 42 with lower ureteric stones. The largest diameter of the stones varied from 7 to 21 mm (mean 9.6 mm). Mild or severe hydronephrosis was present in 53 cases. Mid and lower ureteric stones were treated with the patients in the prone position, with no anaesthesia or pre-medication, and upper ureteric stones in the supine position, with intravenous sedation in 44 cases. RESULTS: Localization of the stones was easy in 81 cases and more difficult in 19, but an intravenous pyelogram was only necessary in three cases. The number of sessions per patient varied from 1 to 3 (mean 1.17). Complete success rate was achieved in 75% of patients and partial success (residual stones < or = 3 mm) in 6%. The stone-free rate was statistically affected by stone size but was independent of stone localization or the degree of obstruction. The rate of infective and obstructive complications was 14% and auxiliary treatments were necessary in 5% of patients. CONCLUSION: In situ piezoelectric ESWL with the EDAP LT 02 device is a convenient and efficient method for the treatment of ureteric stones.

Adult↗
PubMed1995

E-4695, a new C-7 azetidinyl fluoronaphthyridine with enhanced activity against gram-positive and anaerobic pathogens.

E-4695, (-)-7-[3-(R)-amino-2-(S)-methyl-1-azetidinyl]-1-cyclopropyl-1,4- dihydro-6-fluoro-4-oxo-1,8-naphthyridine-3-carboxylic acid, is a new fluorinated naphthyridine with an azetidine moiety. The MICs of E-4695 at which 90% of the isolates were inhibited (MIC90s) were 0.06 to 0.5 microgram/ml for gram-positive cocci, including species of the genera Staphylococcus, Streptococcus, and Enterococcus, and the MIC90s against gram-negative pathogens such as members of the family Enterobacteriaceae (with the exception of Providencia spp. [MIC90, 8 micrograms/ml]) and Pseudomonas aeruginosa were 0.015 to 0.5 microgram/ml. E-4695 inhibited 90% of the Clostridium perfringens and Bacteroides fragilis isolates at 0.25 and 4 micrograms/ml, respectively. Against gram-positive cocci the potency of E-4695 was 2- to 8-fold higher than that of ciprofloxacin, 4- to 8-fold higher than that of ofloxacin, and 8- to 16-fold higher than that of fleroxacin. Against enteric bacteria and P. aeruginosa the potency of E-4695 was, in general, similar to that of ciprofloxacin and eightfold higher than those of ofloxacin and fleroxacin. E-4695 was four- and eightfold more potent than ciprofloxacin against C. perfringens and B. fragilis isolates, respectively. E-4695 and ciprofloxacin showed similar properties when the effects of pH or magnesium concentration were tested on them. E-4695 and ciprofloxacin had substantial reductions of activity only when pH decreased below 4.8. E-4695 and ciprofloxacin activities were not markedly affected by the presence of 5 or 10 mM Mg2+. The presence of serum and human urine at pH 7.2 decreased the activity of E-4695 between two- and fourfold. After an oral dose of 50 mg/kg of body weight, the maximum level in serum, the biological half-life, and the area under the concentration-time curve from 0 to 10 h for E-4695 were 13.2 microgram/ml, 3.3 h, and 45.6 microgram . h/ml, respectively. The area under the concentration-time curve from 0 to 4 h for ciprofloxacin was 2.3 microgram . h/ml at the same dose. Fifty-percent effective doses (ED50S) against Staphylococcus aureus HS-93 infections in mice were 4.5 mg/kg with E-4695 and 37.6 mg/kg with ciprofloxacin. Infection with Streptococcus pneumoniae 29206 was more effectively treated with E-4695 (ED50, 41,2 mg/kg) than with ciprofloxacin (ED50, 200 mg/kg). The ED50 of E-4695 for infections with Streptococcus pneumoniae 1625 was 132.2 mg/kg; ciprofloxacin was ineffective at 400 mg/kg against this strain. E-4695 was also more potent than ciprofloxacin in treatment of infections caused by gram-negative organisms such as Escherichia coli HM-42 (ED50S, 1.0 and 3.9 mg/kg, respectively). The ED50S of E-4695 and ciprofloxacin were 33.0 and 145.5 mg/kg against P. aeruginosa HS-116 and 9.6 and 18.9 mg/kg against P. aeruginosa B-120, respectively. The therapeutic efficacy of E-4695 may depend not only on its in vitro activity but also on its improved pharmacokinetic properties.

Animals↗
PubMed1995

Serial renal transplant surgery: technical reflections concerning third transplants.

From 1972 to 1993, we carried out 803 consecutive renal transplants including 8 third transplants. Exclusively cadaveric, these third renal transplants were implanted by intraperitoneal approach in right iliac position, without previous homolateral transplantectomy in 5 cases. The arterial anastomoses were common (7) or external iliac and hypogastric (1), and the venous anastomoses external (1) and common iliac (3), or inferior vena cava (4). Restoration of urinary continuity was by ureteronecystostomy (Politano-Leadbetter = 4, Grégoir-Lich = 3) or ureteroureteric anastomosis (1). The level of HLA compatibility varied from 2 to 5 identities (mean 3.1) and 4 of the 7 patients explored were hyperimmunized with lymphocytotoxic antibody levels > or = 80%. With the exception of the first of these third transplants, the immunosuppressive protocol associated azathioprine, prednisolone, antilymphocytic serum and cyclosporin. Postoperative sequels were marked by 3 vascular rejections and 1 death from hyperkalemia. Moreover, 1 urinary fistula on ureteroureteric anastomosis settled after percutaneous nephrostomy and placing of an uteric stent endoprosthesis. With a postoperative follow-up of 8-32 months (mean 24), 5 of the transplanted patients (62.5%) have a functional renal transplant with a serum creatinine from 120 to 180 microM/l (mean 140). This brief series, whose failures are exclusively immunological, reveals the remarkable technical reliability for these third renal transplants in right iliac implantation, by median transabdominal approach and above a former transplant site.

Adult↗
PubMed1995

Idiopathic calcium oxalate urinary lithiasis: usefulness of Parks' and Tiselius' indices in the evaluation of the risk of stone formation.

Different indices of the risk of urinary calcium oxalate crystallization were compared to determine their usefulness in detecting the stone-formers particularly prone to recurrence. Urine volume and calcium, oxalate, citrate, magnesium or creatinine were determined in 55 patients presenting with an idiopathic calcium oxalate urolithiasis, as well as in 50 control subjects. On 24-hour urine samples, these elements allowed for the calculation and comparison of different indices of lithogenous risk as proposed by Parks and Tiselius. Both Parks' indices and the urinary citrate-calcium ratio varied significantly between the two groups, but conversely Tiselius' indices were statistically comparable. The three Tiselius' indices taking the 24-hour urine volume into account were also strongly correlated. Parks' index and the urinary citrate-calcium ratio are highly discriminating and potentially relevant to select the stone-formers with a high risk of relapse. Tiselius' indices basically reflect urinary calcium oxalate saturation, and can only be used clinically to control the treatment interfering with this. In this respect, the formula based simply on urine volume, calcium and oxalate over 24 h (Ca0.71.Ox.V-1.2) appears to be sufficient.

Adolescent↗
PubMed1995

Vasopressin stimulates steroid secretion in human adrenal glands: comparison with angiotensin-II effect.

Autoradiographic experiments using iodinated vasopressin analog revealed the presence of specific vasopressin-binding sites in the human adrenal cortex (zona glomerulosa and zona fasciculata). These receptors exhibited a good affinity for arginine vasopressin (3.3 nM), with classical V1a pharmacology and densities of 65 and 135 fmol/mg protein-enriched membranes from zona glomerulosa and fasciculata, respectively. Vasopressin receptors present in both glomerulosa and fasciculata cell-enriched primary cultures were coupled to phospholipase C (ED50, 0.9 and 1.8 nM; maximal stimulation, 4.3- and 5.8-fold, respectively). Vasopressin also stimulated an increase in intracellular calcium through at least two distinct mechanisms: the mobilization of intracellular pools via vasopressin-stimulated inositol phosphate accumulation and the activation of calcium influx. In glomerulosa cell-enriched primary cultures, vasopressin increased aldosterone secretion (ED50, 0.4 nM; maximal stimulation, 2.5-fold) and was found to be as potent as angiotensin-II in stimulating aldosterone secretion, phosphoinositide turnover, and calcium mobilization. In fasciculata cells, vasopressin and angiotensin-II were also able to stimulate cortisol secretion and inositol phosphate accumulation. Moreover, perifusion experiments demonstrated that vasopressin was released from the adrenal medulla. Together, these results indicate that vasopressin can be considered a potent paracrine modulator of adrenal steroid secretion in man.

Adrenal Glands↗
PubMed1995

[Penal aspects of psychiatric intervention: management modes and impact of new criminal legislation].

Psychiatry and criminal justice have been closely related for a long time. Traces of such ties can already be found during the 19th century through the establishment of the contemporary systems of social control. Various questions that will mark the development of policies in this domain were important objects of discussion and analysis: Is mental illness a cause of criminality? Should the "insane" be held responsible for their crimes? What are the appropriate measures to heal, reform, control? In other words, should we consider the individual as sick or as criminal? If these questions are formulated differently nowadays they haven't lost any of their relevance. In this article, we will briefly present the forms of intervention available to the criminal justice system when dealing with persons suffering from mental health problems. This presentation is based on recent studies conducted in Montreal, elsewhere in Canada, as well as in the United States. The main stages of the criminal justice process will be examined, taking into account the recent modifications to the Canadian Criminal Code and its impact on the relations between the courts and psychiatric facilities. This type of situation is not without impact on community mental health for two main reasons. First, with the diminishing public funding of various health services there seems to be a growing practice of criminalization of persons suffering from mental health problems, especially the most vulnerable segments of this population. Secondly, there is a growing trend, in the criminal justice system, of requiring support from community groups or facilities to deal with these criminalized individuals. In the coming years criminalization will constitute an increasing and complex challenge for community mental health.

Canada↗
PubMed1995

[Morbidity of percutaneous biopsy of kidney transplants (Vim-Silverman and Tru-cut needles)].

OBJECTIVES: To evaluate the morbidity of renal transplant biopsies performed after simple ultrasonographic identification of the transplants, using a Vim-Silverman or Tru-cut needle. METHODS: From January 1987 to April 1991, 360 renal transplant biopsies were performed after simple ultrasonographic identification of the transplants, using a Vim-Silverman (n = 204) or Tru-cut (n-156) needle. In 221 transplants, these biopsies were performed because of a rise of serum creatinine (n = 319) or proteinuria (n = 17) or were even performed systematically (n = 24). One to 5 (mean = 1.6) transplant biopsies were performed systematically and the interval between renal transplantation and biopsy varied between 3 days and 11 years. RESULTS: 290 biopsies (80.6%) allowed the analysis of a minimum of 3 glomeruli (mean = 9.3). The yield of the Vim-Silverman needle was significantly greater than that of the Tru-cut model (p = 0.02). 147 biopsies (50.7%) demonstrated acute or chronic rejection, 57 (19.7%) revealed cyclosporin nephrotoxicity, 41 (14.1%) showed acute tubular necrosis and 14 (4.8%) showed glomerulopathy, while 31 (10.7%) were strictly normal. The morbidity of these biopsies was reflected by 37 complications (10.3%), including 30 minor and 7 major complications (2 cases of haemoperitoneum, 4 cases of obstructive anuria and 1 arteriovenous fistula). However, only one case required transplantectomy. These problems were significantly more frequent following inadequate biopsies (< 3 glomeruli, purely medullary, extra-renal). CONCLUSION: Despite the considerable risk of iatrogenic lesions, these biopsies were justified by their potential diagnostic and therapeutic benefit. The prophylaxis of complications of this procedure is based on strict respect of blood pressure and haematological criteria and on real-time ultrasound monitoring of the biopsy and miniaturization of the trocars. The treatment of severe complications has been greatly improved by the development of endourology and interventional radiology, but surgery, and especially transplantectomy, is still occasionally required.

Adolescent↗
PubMed1995

[Ureteral trauma during surgery for aneurysm of the subrenal abdominal aorta. Apropos of 2 complete sections discovered postoperatively].

The lombo-iliac ureter is particularly exposed in surgery of the aorta, particularly for bypass surgery and cure of aneurysms. Two recent cases of complete section of the ureter were discovered post-operatively. Endo-urologic techniques offer a promising means of protecting the upper urinary tract in these procedures. Percutaneous nephrostomy and ureteral catheterism have also been discussed as have been ureteral endoprosthesis and double J ureteroscopy.

Aged↗
PubMed1995

Doctor, would you drink water from your dental unit?

Contamination of dental unit water lines is not new to dentistry, but this problem takes on a new dimension when considering immuno-deficient patients and existing infection-control measures. This study identifies the bacteria involved in the contamination process, estimates the contamination levels and reviews the methods that may be used to control the contamination.

Bacteria↗