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J Perrault

Publications and source records attributed to J Perrault.

At least 37 records · Page 2Linked to original sources
PubMed1994

Enteric protein loss after the Fontan operation.

OBJECTIVE: The current study was undertaken to assess the frequency of excessive enteric protein loss and protein-losing enteropathy in the relatively early period after the Fontan operation. DESIGN: Protein excretion was determined in 26 of 27 consecutive patients who underwent the Fontan procedure between January and June 1990 at the Mayo Clinic. MATERIAL AND METHODS: At two testing intervals during the first 4 months after the Fontan operation, alpha 1-antitrypsin clearance and fecal alpha 1-antitrypsin concentration studies were done. RESULTS: All results were normal for the first postoperative test period (2 to 8 weeks). For the second study period, all 17 patients tested had normal alpha 1-antitrypsin clearances. One of the 17 patients had an appreciably increased fecal alpha 1-antitrypsin concentration and transient protein-losing enteropathy. CONCLUSION: Excessive enteric protein loss and protein-losing enteropathy are relatively uncommon during the first 4 months after the Fontan operation.

Adolescent↗
PubMed1994

Hereditary pancreatitis.

Hereditary pancreatitis is a clinical condition in which typical pancreatitis is associated with an inheritance pattern strongly suggestive of an autosomal dominant trait. Different variants have been described, some with aminoaciduria and some with ductal anomalies. Recurrent attacks are typical and lead to complications more often than in the idiopathic variety. Pancreatic enzyme supplements or antioxidants may help reduce the frequency and/or severity of attacks.

Child↗
PubMed1993

Faithful and efficient in vitro reconstitution of vesicular stomatitis virus transcription using plasmid-encoded L and P proteins.

We demonstrate here that plasmid-expressed polymerase proteins of a negative-strand RNA virus can faithfully reconstitute all aspects of the transcription process carried out by virion cores in vitro. The assay is based on adding purified nucleocapsid templates of vesicular stomatitis virus to extracts of cells expressing L and P viral polymerase proteins via the vaccinia-T7 RNA polymerase recombinant virus. No significant differences were seen between the native virion core reaction and the optimally reconstituted system including ratio of transcripts produced, polyadenylation, net synthesis per template, amounts of polymerase proteins and template, and competence to initiate infection in vivo. Reconstitution was not dependent on cotranslation of P and L proteins in the same cell since nearly as much activity was obtained by mixing extracts expressing each protein individually. Cotransfection with P plasmid, however, stimulated L protein accumulation two- to fivefold relative to transfection with L alone. Surprisingly, deleting a small region in the C-terminal half of the L polymerase protein (amino acids 1638 to 1673) abolished transcription as well as stimulation by P coexpression. Since the polymerase domain of L presumably lies in the N-terminal half of the protein, these results suggest that the putative nucleotide-binding motif in the deleted segment may be involved in an accessory function essential for the transcription process.

Animals↗
PubMed1993

Assessment of the arterial tonometer (N-CAT) for the continuous blood pressure measurement in rapid atrial fibrillation.

The N-CAT is a newly developed arterial tonometer (TBP) able to determine systolic, diastolic and mean arterial blood pressures continuously and noninvasively. The aim of this study was to evaluate the accuracy and reliability of TBP relative to directly measured invasive blood pressure (IBP) in ten haemodynamically stable postoperative cardiac patients who were in rapid atrial fibrillation (HR > or = 100 bpm). There were differences between TBP and IBP for systolic (-1.7 mmHg) and diastolic (+0.9 mmHg) values but not for the mean arterial blood pressures. The N-CAT was able to follow blood pressure changes closely and demonstrated an average systolic, diastolic and mean bias (+/-SD) of -1.71 +/- 4.6, 0.99 +/- 4.6 and 0.33 +/- 4.2 mmHg, respectively. Although these biases are within the required standards for equivalency for noninvasive blood pressure to invasively determined blood pressure, approximately 20% of the readings were > +/- 10 mmHg while only 5% were > +/- 20 mmHg. Moreover, there were occasional discrepancies of sufficient magnitude and duration which may limit the clinical usefulness of the N-CAT in patients in whom continuous and accurate blood pressure measurement is required.

Arteries↗
PubMed1993

Low-dose aprotinin infusion is not clinically useful to reduce bleeding and transfusion of homologous blood products in high-risk cardiac surgical patients.

A high-dose regimen of aprotinin 5-6 million KIU is effective in reducing bleeding and the need for homologous blood products (HBP) associated with cardiopulmonary bypass (CPB). These high doses aim at achieving plasmin and plasma kallikrein concentrations which in vitro are inhibitory but, theoretically, smaller doses could suffice in vivo. Also, aprotinin is an expensive drug, so efficiency requires using the smallest effective dose. Therefore, the efficacy of prophylactic aprotinin 1 million KIU (the maximal dose approved currently) was evaluated in a patient population at high risk of bleeding and of being transfused. Forty-one patients undergoing reoperation or a complex surgical procedure were included in a prospective, randomized, placebo-controlled, double-blind study. Before skin incision, a bolus of 200,000 KIU aprotinin was administered in 20 min, followed by an infusion of 100,000 KIU.hr-1 over eight hours. Control patients received an equal volume of saline. Dryness of the operative field, chest drainage, transfusion of HBP, haemoglobin concentrations, and coagulation variables (including bleeding time) were compared. There were no differences between aprotinin and placebo-treated patients for all clinical and laboratory variables. The apparent ineffectiveness of aprotinin may be explained by the use of an insufficient dose, by a different protocol of administration (e.g., no bolus in CPB prime), or by the inability of aprotinin to decrease bleeding and transfusions any further. Also, the number of patients studied does not exclude the possibility of a Type II error.(ABSTRACT TRUNCATED AT 250 WORDS)

Aprotinin↗
PubMed1993

Amrinone, in combination with norepinephrine, is an effective first-line drug for difficult separation from cardiopulmonary bypass.

A crucial element for weaning patients from cardiopulmonary bypass (CPB) rests on the selection of an appropriate therapeutic regimen. Amrinone, a phosphodiesterase III inhibitor, combines inotropic support with pulmonary and systemic vasodilatation, without increasing heart rate (HR) or myocardial oxygen consumption. These characteristics should be useful in the failing heart during weaning from CPB. Nineteen patients were included in this prospective, open-labelled, phase IV study when systolic blood pressure (DPAP) > 15 mmHg or central venous pressure (CVP) > 15 mmHg, during progressive separation from CPB. At that moment, CPB flow was increased to alleviate heart failure and amrinone administered as a bolus (0.75 mg.kg-1) followed by an infusion (10 micrograms.kg-1.min-1). Weaning from CPB was then resumed and haemodynamic variables (SBP, DPAP, CVP and HR) were compared with those measured at CPB flow when failure had first occurred. Failure to wean from CPB occurred at 57 +/- 28% of full pump flow. After the amrinone bolus, DPAP and CVP decreased by 20% and 21% respectively. Subsequently, 16 patients required the infusion of norepinephrine (4-8 micrograms.min-1) to maintain a SBP > 80 mmHg. Heart rate remained unchanged after the bolus of amrinone, after separation from CPB, and no arrhythmias were noted. Successful weaning from CPB was possible 12 +/- 8 min after the amrinone bolus. Weaning resulted in a cardiac index similar to that measured pre-bypass. Amrinone is rapidly effective during weaning from CPB and, in combination with norepinephrine, provides the necessary inotropic support during this unstable period.

Aged↗
PubMed1993

A simple classification of the risk in cardiac surgery: the first decade.

Since 1980, the operative risk in all our cardiac surgical patients has been assessed before surgery. In light of reports of changes in cardiac surgical populations, we reexamined our practice and risk classification. The purpose of this study was to compare the surgery performed, the characteristics of the patients operated upon and the hospital mortality in our institution in two epochs ten years apart. In 1989-90, the 2029 consecutive cardiac surgical patients who had the same operations as the 500 patients of a 1980 study in our institution were prospectively stratified using our risk classification based on the number of risk factors (RFs) present: normal-risk patient = no RF, increased risk = 1 RF, high risk > or = 2 RFs. These two cohorts of patients were compared. From 1980 to 1990, the proportion of high-risk patients tripled whereas the proportion of normal-risk patients diminished by one third and the proportion of increased risk remained unchanged. The incidence of the following RFs increased: poor left ventricular function, advanced age, emergency surgery, reoperation and other systemic disorders. In coronary artery surgery patients, the incidence of unstable angina/recent myocardial infarction and of obesity also increased. In noncoronary artery surgery patients, the incidence of heart failure increased while obesity remained unchanged. The difference in hospital mortality among the three risk classes was significant within both study periods. The mortality in each risk class and total mortality did not change between 1980 and 1990.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗
PubMed1993

Multicenter trial of d-alpha-tocopheryl polyethylene glycol 1000 succinate for treatment of vitamin E deficiency in children with chronic cholestasis.

BACKGROUND: Malabsorption and deficiency of vitamin E causing neurological degeneration are common consequences of chronic childhood cholestatic liver disease. The objective of this study was to determine the long-term efficacy and safety of d-alpha-tocopheryl polyethylene glycol 1000 succinate (TPGS) in correcting vitamin E deficiency in children with chronic cholestasis who were unresponsive to other forms of oral vitamin E. METHODS: Sixty vitamin E-deficient children with chronic cholestasis unresponsive to 70-212 IU.kg-1.day-1 of oral vitamin E were entered into a trial at eight centers in the United States. After initial evaluation, treatment was started with 25 IU.kg-1.day-1 of TPGS. Vitamin E status, neurological function quantitated by a specific scoring system, and clinical and biochemical parameters were monitored during therapy. RESULTS: All children responded to TPGS with normalization of vitamin E status. Neurological function, which had deteriorated before entry in the trial, improved in 25 patients, stabilized in 27, and worsened in only 2 after a mean of 2.5 years of therapy. No adverse effects were observed. CONCLUSIONS: TPGS (20-25 IU.kg-1.day-1) appears to be a safe and effective form of vitamin E for reversing or preventing vitamin E deficiency during chronic childhood cholestasis.

Adolescent↗
PubMed1993

Long-term follow-up of young patients with chronic hereditary or idiopathic pancreatitis.

We conducted a retrospective study of patients younger than 20 years of age who had a diagnosis of chronic pancreatitis and underwent assessment at the Mayo Clinic between 1960 and 1990. Those with a known etiologic factor for the pancreatitis (such as a virus, trauma, alcohol, or hyperlipidemia) were excluded from the study. We compared the clinical course of the 42 patients who had hereditary pancreatitis (HP)--defined as at least two family members affected by the condition--with that of the 28 patients who had idiopathic pancreatitis (IP). The mean age at initial assessment was 7 years for those with HP and 12 years for those with IP. All patients in both groups had abdominal pain. Vomiting was more frequent in patients with HP than in those with IP; otherwise the initial symptoms were similar in both groups. Patients with HP, however, had more complications, including pseudocysts (seven patients), steatorrhea (four), ascites (three), portal hypertension (two), and diabetes (one), than did patients with IP (one each had diabetes, steatorrhea, and a pseudocyst). Complications or pain necessitated surgical intervention in 23 of 42 patients with HP versus 4 of 28 patients with IP. Overall in comparison with IP, HP seems to be a more severe variant of chronic pancreatitis, inasmuch as it is associated with more frequent complications and need for surgical intervention.

Celiac Disease↗
PubMed1992

Surgical therapy and long-term follow-up of childhood hereditary pancreatitis.

Treatment and a 15-year follow-up survey of 42 patients with hereditary pancreatitis (HP) were compared with 28 patients with idiopathic recurrent pancreatitis (RP) of childhood. There was no difference between the two groups except for pancreatic ductal dilatation and stones in patients with HP. Longitudinal pancreaticojejunostomy (20) or resection and drainage procedures (7) were more commonly required in patients with HP than RP (55% v 14%). There was no surgical mortality. Postoperatively, immediate and complete relief of symptoms was obtained in 43% of patients with HP and 25% of patients with RP. In the remainder, recurrent attacks of pancreatitis abated over 2 years such that 81% of the surgical patients were in good or excellent health. Occasional symptoms persisted in 52% of HP patients and 25% of RP patients. Of the 20 patients with HP or RP undergoing longitudinal pancreaticojejunostomy extending from the head to the tail, 75% were symptom-free on follow-up. However, 3 of 6 patients with poor results had also undergone this procedure. At long-term follow-up of patients who did not undergo operation, 75% of HP patients and 90% of RP patients reported excellent or good health despite the persistent symptoms in 68% and 42%, respectively. Surgery for childhood HP is dependent on the complications present. Longitudinal pancreaticojejunostomy is beneficial for ductal dilatation and associated pseudocysts or pancreatic ascites. The performance of this procedure in the absence of consistent pancreatic duct dilatation will give poor results. Patients without ductal dilatation and the majority of patients with RP may eventually lead near normal lives without resorting to surgery.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

Stepwise phosphorylation of vesicular stomatitis virus P protein by virion-associated kinases and uncoupling of second step from in vitro transcription.

Transcription-competent cores of vesicular stomatitis virus (VSV) contain two tightly bound protein kinase activities capable of phosphorylating the viral P protein (Beckes and Perrault, Virology 184, 383-386, 1991). We examined here the specificity of these kinases for the P protein substrate and their activity during the in vitro transcription process. Conditions favoring the VSVK1 kinase activity resulted in phosphorylation of the P1 species predominantly whereas conditions favoring VSVK2, or transcription conditions, led to an increase in the proportion of the faster migrating P2 and P3 species. A minimum of 2 mol phosphate/mol P protein was incorporated in 1 hr under optimal transcription conditions. Pulse-chase experiments revealed that the VSVK2 activity converted phosphorylated P1 to P2/P3 species. Most or all of the sites modified by VSVK1 (serines only) mapped to the 78 amino acid-long N-terminal fragment of the P protein; additional serine acceptor sites of undetermined location were also phosphorylated under VSVK2 conditions. Pretreatment of virion cores with 5'-p-fluorosulfonylbenzoyl adenosine had little or no effect on P1 phosphorylation but inhibited P1 to P2/P3 conversion nearly completely, with no effect on subsequent transcription. Likewise, the addition of cell extracts had relatively little effect on P1 phosphorylation but strongly inhibited the appearance of P2/P3, without affecting concurrent transcription. We conclude that phosphorylation of the P protein during transcription in vitro is a two-step process carried out by two distinct kinase activities, but only the first step may be essential for viral mRNA synthesis.

Adenosine Triphosphate↗
PubMed1992

Measurement of colonic tissue cyclosporine concentration in children with severe ulcerative colitis.

Recent studies suggest that cyclosporine may be an alternative to colectomy in children with severe ulcerative colitis who fail traditional therapy with bowel rest and high-dose corticosteroids. We report the clinical course of two such children. Patient 1 received oral cyclosporine at 15 mg/kg/day for 1 week followed by 8 mg/kg/day for 6 weeks. Clinical remission occurred within 5 days and has been sustained for 24 weeks after azathioprine was substituted for cyclosporine. Patient 2 received oral cyclosporine at 7-8 mg/kg/day for 7 days after which colectomy was performed due to lack of clinical improvement. Blood cyclosporine levels for patient 1 ranged from 95 to 406 ng/ml and for patient 2 from 36 to 65 ng/ml. Sigmoid colonic tissue cyclosporine concentrations for patients 1 and 2 were 10,058 and 3,205 ng/g, respectively. The patient who responded had significantly higher blood and colonic tissue cyclosporine concentrations than the patient who did not respond. Further studies with larger numbers of patients are needed to determine if there is a correlation between blood and colonic tissue cyclosporine concentrations and clinical response.

Administration, Oral↗
PubMed1991

The stratification of cardiac surgical procedures according to use of blood products: a retrospective analysis of 1480 cases.

The use of blood products in 1480 consecutive cases of adult cardiac surgical procedures over a period of 15 mth was studied retrospectively using the database of the Department of Anaesthesia of the Institut de Cardiologie de Montréal. Use of blood products was compared in patients having (1) coronary artery bypass grafting, (2) valvular surgery, (3) or a combination of 1 and 2. First operations were compared with reoperations. Overall, the use of homologous blood products was greatest in patients of Group 3, intermediate in patients of Group 2, and smallest in patients of Group 1. Reoperations were associated with an increase in intraoperative transfusion of packed red blood cells, but postoperative chest drainage was similar to first operations. When all blood products (packed red blood cells, fresh frozen plasma and platelets) were taken into consideration, patients undergoing primary CABG or valve surgery were the least exposed to homologous blood donors (five and six units transfused respectively). Repeat CABG was associated with an intermediate exposure to homologous blood products (eight units). Finally, primary and repeat combined procedures, and repeat valve surgery were associated with the greatest exposure to foreign blood products (10, 13 and 10 units respectively). The data presented in this study provide a rational basis for stratification of procedures according to the expected use of blood products, particularly in view of future studies which may be planned to examine the efficiency of blood conservation strategies.

Aged↗
PubMed1991

Two distinct protein kinase activities in vesicular stomatitis virions phosphorylate the NS transcription factor.

Two vesicular stomatitis virion proteins, NS and M, are phosphorylated in vivo before packaging and in vitro during the transcription process carried out with disrupted virions. Phosphorylation of NS is thought to be essential for transcription but which of the many acceptor sites is or are involved in this function and which protein kinase(s) is responsible still need to be resolved. We recently reported that the virion-associated kinase which modifies M protein is most likely a different enzyme than that phosphorylating NS (Beckes et al., Virology 169, 161-171 1989). Here we present additional evidence for the presence of distinct enzymes modifying M vs NS substrates and also show that at least two distinct kinase activities modify NS protein. Each of the three activities displayed different optimum reaction conditions, phosphate donor preferences, and sensitivity to inhibition by N-ethylmaleimide.

Capsid↗
PubMed1991

6-mercaptopurine therapy in selected cases of corticosteroid-dependent Crohn's disease.

Nineteen patients (12 children and 7 adults) with severe Crohn's disease, all of whom were dependent on corticosteroids, were treated with 6-mercaptopurine. All patients received a daily dose of 6-mercaptopurine of 50 mg; in two pediatric patients with a poor response after 2 months, the dosage was increased to 75 mg/day. A complete or partial response to 6-mercaptopurine therapy was noted in 47% of patients, and therapy failed in 53%. The age of the patients, prior resection, or initial symptoms did not influence the response. The clinical response was better in male than in female patients and in patients with involvement of both the small intestine and the colon than in those with only enteritis. 6-Mercaptopurine is a possible alternative to long-term corticosteroid therapy or surgical treatment in selected patients with severe Crohn's disease.

Adolescent↗
PubMed1990

The surgical management of children with ulcerative colitis. The old vs. the new.

The authors' experience with children who have chronic ulcerative colitis was reviewed to compare their current surgical approach (ileoanal anastomosis) with earlier methods of management. Between 1960 and 1984, 137 children with chronic ulcerative colitis underwent surgery (mean duration of follow-up, 7.1 years). In 91 patients, the procedures were a total proctocolectomy with ileostomy or Kock pouch (66) or a lesser colectomy with either an ileostomy (16) or an ileorectal anastomosis (9) (group I). Forty-six patients underwent an ileoanal anastomosis procedure (group II). Children in group I were more likely to have significant preoperative loss of weight, a debilitated condition, and malnutrition. Urgent or emergency surgical intervention was required in 25 percent of patients in group I but in only 4 percent of patients in group II. Trends included 1) a younger age at operation in group II, 2) a higher mortality in group I (7.7 percent) than group II (0 percent), and 3) a higher perioperative mortality with emergency operations (23 percent) than elective procedures (1.6 percent). In group I, 98 percent of patients had an abdominal ostomy, but no patients in group II had an abdominal ostomy. The children with an ileoanal anastomosis had an average of 4.8 stools during waking hours and 1.3 stools each night. On the basis of this experience, the authors recommend use of the ileoanal anastomosis procedure in the surgical treatment of chronic ulcerative colitis in children.

Adolescent↗