Biomedical subjects
Publications and source records attributed to J Perrault.
Gastric heterotopia within the biliary system is rare and is generally an incidental finding. Only a few patients have biliary symptoms specifically attributable to heterotopia. A unique case of symptomatic gastric heterotopia of the common bile duct is presented and the literature reviewed.
The purpose of this study was to carry out a long-term study of the ileoanal anastomosis (IAA) in children and young adults, comparing the straight IAA to the J pouch. One hundred twenty-one young people who had undergone IAA were studied, with 114 available for long-term follow-up. One hundred one were 18 years and under. Forty-nine patients had a straight IAA and 72 had a J-pouch reservoir. There were no deaths. After surgery, three children had intraabdominal sepsis and one had pelvic sepsis, but it did not lead to excision of the IAA. The mean stool frequency in all 114 patients was 5.0 +/- 2.5 per day and 1.2 +/- 1.1 at night. The mean number of stools for the straight IAA was 6 per day and 2.1 at night. The mean number of stools for the straight IAA with balloon dilations was 5.8 per day and 1.2 at night, and for the J pouch it was 4 per day and 1 at night. Patients with both the J pouch and straight IAA had good to excellent sensation, with patients with the J pouch always able to distinguish flatus from stool in 87% of patients and almost always in 13%. Daytime continence was very good in both groups. Moderate nighttime loss of stool occurred in 10 patients, 6 with a straight IAA and 4 with a J pouch. Ninety-five percent of the 114 patients were satisfied or very satisfied, with most children with a J pouch very satisfied. The J pouch remains the procedure of choice in young people.
The vesicular stomatitis virus (VSV) NS and M proteins are not only phosphorylated in vivo but are also further modified by the virion-associated protein kinase(s) concomitantly with the in vitro transcription process. Although NS phosphorylation is necessary for this transcription, no function has yet been ascribed for M protein phosphorylation. We show here that all phosphates added to M protein in vitro mapped to the trypsin-sensitive N-terminal basic domain (residues 1-43). The major site(s) (approximately 93%) corresponded to one or more of three serine residues within the first 17 amino acids. Nearly 1 mol phosphate/mol protein was added in vitro under optimal conditions suggesting that only one of these three candidate serine residues corresponds to the major site. This same M protein domain is thought to play an important role in virus RNA synthesis by inhibiting transcription. We show here that in vitro phosphorylation did not appear to affect this function. Two critical serine residues in the VSV NS protein were previously reported to be phosphorylated during in vitro transcription (D. Chattopadhyay and A. K. Banerjee, 1987, Cell 49, 407-414). The sequence flanking these NS serines is very acidic while that of all three candidate phosphoserines in the M protein is very basic. We therefore predict that at least two distinct serine-specific kinase activities are packaged in virions, one specific for M and one specific for NS.
We have carried out an exhaustive search for amino acid sequence similarities between vesicular stomatitis virus (VSV) proteins and database entries. Unexpectedly, we found that the L polymerase protein contains two blocks of sequence (residues 725-1102 and 1291-1671) with distant but statistically significant similarity to the catalytic domain of tyrosine-specific protein kinases. The first kinase-like region is most similar to members of the Abl subfamily, Fes and Fps (26.6% and 27.3% identity, respectively), whereas the second region is closest to members of the platelet-derived growth factor receptor (PDGFR) subfamily, PDGFR and Kit (30.4% and 25.9% identity, respectively). Multiple alignment of the catalytic domain of these kinases to all three rhabdovirus L protein sequences available (VSV Indiana, VSV New Jersey, and rabies) revealed that the polymerases contain many but not all residues well conserved in the protein kinase family. Similarity was highest for VSV Indiana and lowest for rabies. We conclude that the kinase-like regions in the rhabdoviral L proteins are probably very distantly related to the protein kinase family. The similarities could either reflect contemporary protein kinase activity or represent some other function(s) associated with these large multifunctional polymerase proteins. Our findings also shed new light on questions of the origins and evolution of RNA viruses.
The template for transcription of the vesicular stomatitis virus (VSV) genome consists of a negative-strand RNA (approximately 11 kb) tightly associated with approximately 1250 copies of the nucleocapsid or N protein (N-RNA template). The interaction between the virion-associated polymerase and this template was probed with a novel assay using purified N-RNA complexes added to detergent-disrupted uv-irradiated standard virions or unirradiated defective interfering (DI) particles. In contrast to the well-known stability of assembled cellular transcription complexes, the VSV polymerase copied exogenously added templates efficiently and yielded products indistinguishable from control virus transcription. Addition of uv-irradiated N-RNA templates to unirradiated virus effectively competed for transcription of endogenous template indicating that most or all of the polymerase can freely redistribute. Furthermore preincubation of virus and added templates at high ionic strength to solubilize L and NS polymerase proteins did not release additional active enzyme for redistribution. Pretranscription of virus also had little or no effect on redistributed activity indicating that polymerase complexes are capable of multiple rounds of synthesis beginning at the 3' end promoter. Unexpectedly, titration with saturating amounts of added N-RNA showed that active polymerase complexes are only in slight excess relative to template in standard or DI particles despite the large surplus of packaged L and NS polypeptides. Moreover, added standard virus templates competed equally well for the redistributing polymerase from DI particles or standard virus indicating no significant polymerase-binding preference for interfering templates. These findings bear important implications regarding mechanisms of VSV transcription and replication.
In a continuation of previous efforts to study the modified ATP requirements for RNA synthesis by poIR mutants of vesicular stomatitis virus (VSV), we have used a novel reconstitution assay to show that it is the template moiety of the mutants, not the polymerase proteins, which governs both the increased utilization of the ATP analog, beta, gamma-imido ATP (AMP-PMP), and the loss of a positive cooperativity-like response to varying ATP concentrations. Assays utilized uv-irradiated virus as a source of polymerase proteins and purified N-RNA as templates. Homologous and heterologous transcriptase reactions were carried out with wild-type (wt) virus and each of the two independently isolated poIR mutants. We show that in the presence of wt N-RNA template, substitution of AMP-PNP for ATP resulted in only approximately 5% of control RNA synthesis regardless of which source of polymerase was used. Furthermore, all reactions containing wt N-RNA template responded to varying ATP concentrations with a concave, upward-shaped Lineweaver-Burke plot generally indicative of positive cooperativity effects. In contrast, all reactions which utilized N-RNA templates from the poIR mutants showed an increased utilization of AMP-PNP (greater than 20%) and a more characteristic Michaelis-Menten response to changing ATP concentrations. These findings strongly support the notion that the template-associated nucleocapsid protein modulates the utilization of an ATP site which is directly or indirectly involved in VSV RNA synthesis.
We describe five patients who had chronic recurrent gastroduodenal ulcers and pain, intestinal obstruction, bleeding, or a combination of these symptoms. Four patients required surgical intervention because of a poor response to medical therapy. The ulcers recurred in all patients, despite evidence of achlorhydria in two of them. Although the patients denied the use of salicylates, all of them had therapeutic blood levels of salicylates. A salicylate level should be determined in patients with severe ulcer disease that is resistant to medical therapy or that is recurrent after appropriate surgical therapy when the presence of hypergastrinemia or hyperchlorhydria has been definitely excluded. A low serum level of uric acid can also be a clue to the abuse of salicylates.
We conducted a pilot study to assess the feasibility and efficacy of postdilution hemofiltration (PDHF) in the management of acute hepatic failure. From January 1984 through May 1986, we encountered seven patients with acute hepatic failure and entered these consecutive patients in the study; three had non-A, non-B hepatitis and one each had type B hepatitis, fulminant Wilson's disease (hepatolenticular degeneration), acute allograft (liver) failure, and acute fatty liver of pregnancy. Two of these seven patients were unable to undergo PDHF because of a precarious hemodynamic status. Of the five patients treated with PDHF, four had amelioration of hepatic encephalopathy; in two of these patients, a close temporal relationship was noted between the improvement and the procedure. Four patients had appreciable thrombocytopenia related to PDHF and bleeding complications. Our preliminary results support a possible role for PDHF as a temporary artificial liver support system for patients with acute hepatic failure.
We report a case of bleeding esophageal varices associated with lymphoma. Splenectomy alone reversed the patient's portal hypertension as assessed hemodynamically and clinically. Mechanisms leading to portal hypertension in the setting of splenomegaly from hematologic disorders are discussed. An approach to operative management of these patients, based on preoperative hemodynamic measurements, is suggested for future consideration.
An alternative technique for creation of a Drapanas shunt was used in a 12-year-old boy with upper gastrointestinal bleeding. Dissatisfaction with available prosthetic grafts and the inherent limitations of other autogenous materials led to the use of a spiral saphenous vein graft to bridge the superior mesenteric vein and the inferior vena cava. Patency of the graft was demonstrated 1 year postoperatively, and the patient has not had further bleeding episodes for 2 years postoperatively. Continued use of this operation is necessary to determine its usefulness.
We report a pedigree in which a syndrome that resembled familial Mediterranean fever occurred in four family members over three successive generations. All four patients had systemic amyloidosis. Typically, patients with familial Mediterranean fever show an autosomal recessive inheritance pattern. The disorder commonly afflicts Sephardic Jews, Arabs, and persons of Turkish descent. Colchicine therapy dramatically reduces the attack rate of serositis. The family described herein is unique because of their European ethnicity and the autosomal dominant inheritance pattern. Unlike typical familial Mediterranean fever, colchicine had no influence on the attacks and did not prevent amyloidosis in the three patients who received this treatment.
Collagenous colitis is an unusual cause of chronic, watery diarrhea. To characterize this disease, we reviewed biopsy specimens and the clinical records of 17 patients (9 women and 8 men) with this diagnosis. Intermittent diarrhea with symptom-free intervals lasting years was found in 7 of the 17 patients. Two patients had incapacitating arthralgias, and nine had a mild weight loss. Collagen deposition beneath the surface epithelium formed a continuous layer in 11 but was discontinuous in 5 of the 16 patients who had undergone rectal or colonic biopsies at our institution. The thickness of the collagen band was variable (maximum, 93 microns). The symptoms of the patients did not correlate with the thickness of the collagen layer. Variability in collagen thickness may be related to disease phase and increases the need to obtain multiple biopsy specimens from the sigmoid colon and rectum. The optimal treatment for collagenous colitis is difficult to determine because three of six patients treated only symptomatically in our study had resolution of their diarrhea.
Cleavage of the beta-gamma bond of ATP is required for wild-type (wt) vesicular stomatitis virus transcription in vitro. Recent findings have established that a domain-specific phosphorylation of the virus NS protein is necessary for activity. We report here that RNA synthesis catalyzed by purified standard wt virions responded cooperatively to various ATP concentrations, with half-maximal activity at approximately 500 microM. In contrast, mutant polR1 standard virions and wt defective interfering particles both showed conventional Michaelis-Menten kinetic profiles with Km values of approximately 143 and approximately 133 microM, respectively. The former synthesize readthrough products of the leader-N gene junction in addition to plus-strand leader RNA and mRNAs, whereas the latter synthesize only minus-strand leader RNA. The cooperative response of wt virus products, however, was specific to mRNAs; the small fraction of the total products corresponding to plus-strand leader approximated Michaelis-Menten behavior. Since the unique phenotype of the polR mutants correlates with the synthesis of replicationlike products in vitro, the affected ATP-requiring function most likely regulates both transcription and replication. We suggest that this mutated function involves phosphorylation of viral proteins.
In this communication we show that the RNA genomes of vesicular stomatitis, Sindbis, and reoviruses can specifically hybridize under stringent conditions to the large rRNAs present in HeLa cell cytoplasmic extracts. In addition, we show that some virus genome RNAs can also hybridize to each other. On the basis of our previous detailed studies identifying specific regions of hybridization between the poliovirus genome and 28S rRNA, we suggest that a similar phenomenon of "patchy complementary" may be responsible for the interactions described here (M. A. McClure and J. Perrault, Nucleic Acids Res. 13:6797-6816, 1985). The possible biological implications of these cross-reacting hybridizations and practical considerations in the use of viral probes for diagnosis are discussed.
The RNA genome of poliovirus hybridizes to 28S and 18S rRNAs of higher eukaryotes under stringent conditions. The hybridization detected by Northern blot analyses is specific since little or no signal was detected for yeast or prokaryotic rRNAs or other major cellular RNAs. Southern blot analysis of DNA clones of mouse rRNA genes leads us to conclude that several regions of 28S rRNA, and at least one region in 18S rRNA, are involved in the hybridization to polio RNA, and that G/C regions are not responsible for this phenomenon. We have precisely mapped one of these hybridizing regions in both molecules. Computer analysis confirms that extensive intermolecular base-pairing (81 out of 104 contiguous bases in the rRNA strand) could be responsible for this one particular site of interaction (polio genome, bases 5075-5250; 28S rRNA, bases 1097-1200). We discuss the possible functional and/or evolutionary significance of this novel type of interaction.
Recent improvements in the technique of colectomy, rectal mucosectomy, and endorectal ileoanal anastomosis allow a satisfactory result in most patients. However, the clinical outcome is not entirely satisfactory in about 5% to 10% of patients because of excessive stool frequency or episodic fecal incontinence or both. We evaluated anoneorectal function postoperatively to help explain the mechanisms of the difficulties. Six patients with imperfect functional results (group 1) and 6 with good functional results (group 2) after ileoanal anastomosis and closure of the loop ileostomy were compared with 12 healthy volunteers who had not had operation, through a series of tests designed to evaluate anal sphincter and neorectal function. All patients were instructed in balloon dilation of the neorectum to develop a reservoir while awaiting closure of the ileostomy. Anal sphincter manometric measurements of resting and squeeze pressures were obtained with a 4-channel probe attached to a noncompliant pneumohydraulic perfusion system. Incremental inflation of an intraluminal bag while pressures were simultaneously recorded allowed determinations of neorectal capacity and distensibility. The efficiency of neorectal evacuation was assessed by instilling a labeled synthetic viscous load into the distal bowel. Patients in group 1 had lower resting anal pressures (P less than 0.05), lower squeeze pressures (P less than 0.05), smaller neorectal capacities (P = 0.13), and less neorectal distensibility (P = 0.27) than patients in group 2. Furthermore, the values for patients in group 2 closely approximated those found in healthy volunteers.(ABSTRACT TRUNCATED AT 250 WORDS)
Indicine N-oxide is the first member of the large class of compounds comprised of pyrrolizidine alkaloids and their N-oxides to be studied in the treatment of cancer in humans. Twenty-two patients with refractory acute leukemia received indicine N-oxide daily for 5 consecutive days in a dose-seeking study. Of eight patients with refractory acute lymphocytic leukemia, one had a complete remission, and one had a partial remission. Of 11 patients with refractory acute nonlymphocytic leukemia, 2 patients had complete remissions. Of three patients with blast crisis of chronic granulocytic leukemia, one patient had a partial remission. Five patients had severe hepatic toxicity, probably due to veno-occlusive disease induced by the drug. Whether hepatotoxicity and antileukemic activity are a result of the same mechanism of action of indicine N-oxide is not known.
The genome structure and terminal sequences of a 'copyback' defective interfering (DI) particle ST1, and a novel complexly rearranged 'snapback' DI particle ST2 of vesicular stomatitis virus have been determined. The ST1 DI genome RNA possesses 54 base long inverted complementary termini, the 5' end of which is homologous to the standard virus genome 5' end. Following this region of inverted complementarity the DI RNA 5' end continues to be homologous to standard virus RNA 5' sequences, whereas the 3' end diverges into sequences within the virus L gene internal sequences. ST2 DI genome RNA does not contain colinear covalently linked plus and minus sense RNA copies of the standard infectious virus RNA 5' terminus as predicted from the prototype snapback DI structure, but instead appears to be a hairpin copy of the ST1 DI RNA genome. This is the first evidence suggesting that DI particles may be generated from RNA templates other than the standard virus RNA. Generation models and the implications of these findings for RNA virus evolution are discussed.