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J F Charles

Publications and source records attributed to J F Charles.

At least 37 records · Page 2Linked to original sources
PubMed1995

Comparison of toxin overlay and solid-phase binding assays to identify diverse CryIA(c) toxin-binding proteins in Heliothis virescens midgut.

The binding proteins, or receptors, for insecticidal Bacillus thuringiensis subsp. kurstaki delta-endotoxins are located in the brush border membranes of susceptible insect midguts. The interaction of one of these toxins, CryIA(c), with proteins isolated from Heliothis virescens larval midguts was investigated. To facilitate the identification of solubilized putative toxin-binding proteins, a solid-phase binding assay was developed and compared with toxin overlay assays. The overlay assays demonstrated that a number of proteins of 170, 140, 120, 90, 75, 60, and 50 kDa bound the radiolabeled CryIA(c) toxin. Anion-exchange fractionation allowed the separation of these proteins into three toxin binding fractions, or pools. Toxin overlay assays demonstrated that although the three pools had distinct protein profiles, similar-size proteins could be detected in these three pools. However, determination of toxin affinity by using the solid-phase binding assay showed that only one of the three pools contained high-affinity binding proteins. The Kd obtained, 0.65 nM, is similar to that of the unsolubilized brush border membrane vesicles. Thus, the solid-phase binding assay in combination with the toxin overlay assay facilitates the identification and purification of high-affinity B. thuringiensis toxin-binding proteins from the insect midgut.

Animals↗
PubMed1994

[Value of colonic irrigation. Long-term followed-up in 432 colostomized patients].

OBJECTIVES: Irrigating colostomies allows patients to achieve nearly complete fecal continence using a simple technique. We assessed long-term results in our series of 432 patients. METHODS: From 1979 to 1992, we followed 432 patients who had undergone definitive colostomy surgery (mean follow-up = 8.4 years). RESULTS: Colonic irrigation was impossible in 281 cases mainly due to retarded patient information (42%) or patient incapacity (31%). It was possible in 151 patients (globally 31%). In patients with abdominoperineal amputations the rate was 63%, for Hartmann procedures 17% and for derivations 6%. Most of the derivations were supraombilical colostomies (n = 51) including 6 who used colonic irrigation. No complications related to the technique were observed and minor incidents (usually problems with the cannula and/or pain) occurred in 61 patients. Thirteen patients (9%) abandoned the technique including 5 who complained of incontinence. CONCLUSIONS: Based on these observations, we conclude that colonic irrigation is not used enough. The key to success is a quality stomy and early patient information and training. This technique is particularly adapted for active patients. It is performed every 48 hours and lasts about 35 minutes.

Adult↗
PubMed1994

[Cavernous hemangioma of the spleen: values and limitations of ultrasonic and computed tomographic diagnosis].

A case of a cavernous haemangioma associated with an hepatic haemangioma is reported. It presented in the form of a hyperechogenic mass on ultrasound imaging. On the Computed Tomography scan with contrast, the splenic tumour became progressively hyperdense: this last characteristic is observed in 6 out of 9 cases reported in the literature. MR imaging seems to allow an accurate preoperative diagnosis; nevertheless, splenectomy is often indicated because of the risk of rupture, in which case histological examination removes any doubt concerning an exceptional malignant form.

Female↗
PubMed1993

TP53 gene mutation profile in esophageal squamous cell carcinomas.

Esophageal squamous cell carcinoma is a form of cancer occurring most commonly in males, particularly those living in some areas of Asia, Africa, and western Europe. In some of these tumors, a sequence alteration has been identified in the coding region of the TP53 gene which is known to inactivate the tumor suppressor function of its product. Using a GC clamp (i.e., a GC rich domain) denaturing gradient gel electrophoresis assay we have been able to identify sequence modifications in 27 of the 32 tumor samples analyzed (84%). Most of the mutations occur in exon 6, a region of the gene which has not previously been reported as being a hot spot for the mutations of other cancers. Twelve of the mutations reported here have not been described in other types of tumors and these consist mostly of frameshift or splice mutations. The distribution of mutations [transitions (45%), transversions (34%), and frameshift (21%)] suggests that the etiological contribution of genotoxic factors might be complex and might associate different exogenous and endogenous mutagen exposures.

Adult↗
PubMed1993

Clostridium bifermentans serovar malaysia: characterization of putative mosquito larvicidal proteins.

The toxicity of Clostridium bifermentans serovar malaysia to mosquito larvae is due to protein toxins, belonging to a novel class of insecticidal toxins. Toxic extracts contains three major proteins of 66, 18 and 16 kDa. The 18-kDa and 16-kDa proteins are probably involved in toxicity. They are synthesised during sporulation, concomitant with activity. They are absent from non-toxic strains of C. bifermentans and are present at very low levels in non-toxic C. bifermentans serovar malaysia cultures produced at 42 degrees C. The 66-kDa protein is present throughout the growth phases of C. bifermentans serovar malaysia, and an immunologically related 66-kDa protein is present in non-toxic C. bifermentans strains.

Animals↗
PubMed1993

[Postoperative obstructions].

The intestinal obstructions after a laparotomy in adult may be caused by an inflammatory or a mechanic pathology; the incidence of the bowel obstruction in the early postoperative period is about 0.5 to 2% of all surgical procedures; these obstructions are often related to the degree of contamination or infection; contrary to postoperative paralytic ileus, they result in a reoperation, so as a peritonitis may be associated. In the later postoperative period intestinal obstructions may be caused by adhesions, internal strangulation or fibrosis bridles; these obstructions are frequent and they affect especially the small intestine (5% of laparotomies will be complicated by small bowel obstruction). The intestine volvulus due to bridles or adhesions is observed in approximately 10% of cases and the diagnosis must be conjured up in principle because it necessities an operation immediately; it's the same for the strangulation by incarceration. The absence of classic indicators of gangrene permits a non-operative treatment using a naso-gastric tube decompression during 24 to 48 hours: generally the causes of obstruction are small bowel adhesions, nevertheless it's important to eliminate a colonic obstruction. The management of chronic postoperative adherences is a difficult problem because the iterative operations increase the risk of intestinal obstructions; the video-laparoscopic surgery seems to be a promising technique to prevent and to treat (laparoscopic adhesiolysis) the post-operative adherences; its results are not evaluated.

Humans↗
PubMed1993

Respective role of the 42- and 51-kDa components of the Bacillus sphaericus toxin overexpressed in Bacillus thuringiensis.

The 42- and 51-kDa protein genes of Bacillus sphaericus 1593 have been subcloned independently downstream from the cytA gene promoter of Bacillus thuringiensis serovar israelensis and introduced into a non-mosquitocidal strain of Bacillus thuringiensis. Consequently, each protein was overproduced and accumulated as inclusion bodies which were purified. For the first time, the 42-kDa protein inclusions alone were found to be toxic to Culex pipiens larvae (LC50 at 48 h 300 ng ml-1); in contrast, the 51-kDa protein inclusions were not. Moreover, a synergistic effect between these two components was observed.

Animals↗
PubMed1993

Immunological localization of Bacillus thuringiensis serovar israelensis toxins in midgut cells of intoxicated Anopheles gambiae larvae (Diptera: Culicidae).

Fourth instar larvae of Anopheles gambiae were intoxicated with doses of purified crystals from Bacillus thuringiensis serovar israelensis (Bti) corresponding to 50-fold the LC50 after 24 h. Midguts were dissected after various contact times, then processed for immuno-light and -electron microscopy. Immunodetection on thin sections was performed using affinity-purified rabbit IgG against Bti crystal CryIVD or CytA polypeptides, in combination with anti-rabbit IgG/peroxidase. Both polypeptides were detected by optical and electron microscopy after 15 min of contact with Bti crystals on the apical brush border of midgut cells, but only in the gastric caeca and posterior stomach. No specific signal was detected in the other parts of the midgut, i.e. the cardia cells and the anterior stomach. These results confirm that mosquito midgut cells are the primary target for the toxins and that binding to specific receptors on the apical microvilli membrane is the initial step of delta-endotoxin action.

Animals↗
PubMed1993

Inclusion bodies and crystals of Bacillus sphaericus mosquitocidal proteins expressed in various bacterial hosts.

Mosquitocidal proteins of 42 and 51 kDa from Bacillus sphaericus were produced in acrystallogenic B. sphaericus and B. subtilis strains. In both species, transformants containing each protein expressed individually were non-toxic for mosquito larvae and produced small inclusions which did not have a crystalline ultrastructure. When both components of the binary toxin were expressed together, toxicity was restored: oval and round amorphous inclusions were produced in B. subtilis, and typical native-type crystals were synthesized in B. sphaericus. In B. subtilis, native-type crystals were produced only when the two components of the binary toxin were synthesized as a 93-kDa fusion protein.

Bacillus↗
PubMed1993

[Isolated portal vein thrombosis: a rare complication of chronic pancreatitis].

In chronic pancreatitis (CP) portal vein thrombosis (PT) is a less well known complication than splenic vein thrombosis (ST). In the literature up until 1990, 26 cases with PT, have been reported and only 10 cases presented a isolated PT, without ST. We report a new case of isolated PT without ST in a non alcoholic man, who presented with gastroesophageal CP and a cavernomatous transformation of the portal vein. No varices ere detected by endoscopy; because the risk of bleeding was very small, a prophylactic treatment was unnecessary. The pancreas was resected preserving the spleen and cavernomatous transformation or the periportal veins and the patient was cured from his pains. The surgical tactic is an original treatment, particularly when curable pancreatic cancer is suspected.

Adult↗
PubMed1992

Binding of Bacillus sphaericus binary toxin to a specific receptor on midgut brush-border membranes from mosquito larvae.

The presence of specific receptors for Bacillus sphaericus binary toxin on brush-border membrane fractions (BBMF) from Culex pipiens larvae midgut cells was demonstrated by an in vitro binding assay. Both activated and radiolabelled polypeptides from the 51-kDa and 42-kDa binary toxin of B. sphaericus 1593 specifically bound to BBMF. Direct binding and homologous competition experiments indicated a single class of B. sphaericus toxin receptors, with a dissociation constant (Kd) of approximately 20 nM and a maximum binding capacity (Bmax) of approximately 7 pmol/mg BBMF protein. The sugars GalNAc, GlcNAc and N-acetyl neuraminic acid had no detectable inhibitory effect on toxin binding to C. pipiens BBMF. Binding experiments with the non-susceptible mosquito species Aedes aegypti failed to detect significant binding of B. sphaericus binary toxin to A. aegypti BBMF.

Acetylgalactosamine↗
PubMed1992

[Primary colonic intussusception protruding from the anus in adults. Two cases].

The authors report two cases of colonic intussusception in the adult protruding from the anus--or colon-anal intussusception--, not due to a tumor. The first case was a chronic ileo-caeco-colique intussusception, the second case was an acute colo-rectal intussusception. Colo-anal intussusceptions are very rare: less than twenty cases have been described since 1925 in adults. The absence of a tumor origin in our cases represents a special feature, as only three other similar cases have been described. The surgical treatment in both cases was primary colonic resection without colostomy. The surgical treatment of the first case was subtotal colectomy with ileo-rectal anastomosis. The second case was primarily reduced by barium enema which allowed optimal secondary surgical resection of a prepared colon.

Adolescent↗
PubMed1992

[Ivor Lewis' operation for epidermoid cancer of the esophagus. Immediate and late results. Apropos of 168 cases].

168 Ivor Lewis operations for squamous carcinoma of the lower esophagus are reviewed. 155 men and 13 women with a mean age of 59 years were operated on. 46 tumors were stage I and II, and 122 were stage III. Operations were considered to be curative for 120 patients and only palliative for 48. An esophagectomy associated with lymphadenectomy was performed through laparotomy and right thoracotomy. Feeding jejunostomy and pyloroplasty were routine. EEA or ILS 25 staplers were used to perform esophagogastric anastomosis and the gastroplasty tube was fashioned by TA 90 stapler. In every case an extended esophagectomy was performed with anastomosis between 3 ans 7 cm below the pharyngo-esophageal junction. Postoperative mortality was 4.7%. There were 10 leaks (6%) and 28 pulmonary complications. Median actuarial survival is 17 months. Actuarial survival at 2 years is significantly greater for stages I and II (68.4%) than for stage III (23.2%) (p < 0.01). Ivor Lewis esophagectomy is a reliable procedure to treat squamous carcinoma of the lower two thirds of the esophagus ensuring a good quality of life.

Adult↗
PubMed1992

[Primary colonic intussusception protruding from the anus in adults. Two cases].

The authors report two cases of colonic intussusception in the adult protruding from the anus--or colo-anal intussusception--, not due to a tumor. The first case was a chronic ileo-caeco-colique intussusception, the second case was an acute colo-rectal intussusception. Colo-anal intussusceptions are very rare: less than twenty cases have been described since 1925 in adults. The absence of a tumor origin in our cases represents a special feature, as only three other similar cases have been described. The surgical treatment in both cases was primary colonic resection without colostomy. The surgical treatment of the first case was subtotal colectomy with ileo-rectal anastomosis. The second case was primarily reduced by barium enema which allowed optimal secondary surgical resection of a prepared colon.

Acute Disease↗
PubMed1991

Ivor Lewis operation for epidermoid carcinoma of the esophagus.

One hundred patients, 95 men and 5 women with a mean age of 59 years (age range, 35 to 77 years), were treated by the same initiate surgeon in practice from 1982 to 1988 for epidermoid carcinoma of the lower two-thirds of the esophagus using the Ivor Lewis procedure. Fifty-eight tumors were located in the middle third of the esophagus and 42, in the lower third. Postoperative staging revealed 30 stage I/II and 70 stage III carcinomas (ie, tumors extending beyond the esophageal wall or lymph node extension). Operative procedure was considered curative in 70 patients and palliative in 30 patients. The same procedure has been used for all patients. In all patients we were able to perform extended esophagectomy with anastomosis located 3 to 7 cm under the pharyngoesophageal junction. Postoperative mortality was 4%. Morbidity due to leakage was 7%; proper drainage enabled spontaneous healing in 5 patients. Fifteen patients had pulmonary complications, none of which fatal, Median actuarial survival was 17 months. Actuarial survival at 24 months is significantly higher for patients in stage I and II (68.4%) than for patients in stage III (23.2%) (p less than 0.01). The Ivor Lewis procedure is a safe surgical approach for the treatment of the esophageal carcinoma that has a high survival rate and allows a good quality of life.

Actuarial Analysis↗