Biomedical subjects

H Blanchard

Publications and source records attributed to H Blanchard.

At least 19 recordsLinked to original sources

PubMed2001

[Blunt injuries of the pancreas in children].

STUDY AIM: Conservative management is mainly proposed for pancreatic trauma without ductal injuries. The aim of this retrospective study was to assess our experience with traumatic pancreatic injuries and to compare patients with medical or surgical treatment. PATIENTS AND METHOD: From January 1989 to December 1998, 21 children, 13 boys and 8 girls with a mean age of 8 years (range: 1 to 17 years) were treated for pancreatic injuries. Main mechanisms of injuries were bicycle's falls (n = 7), passengers in motor vehicle collision (n = 6), and other road collisions (n = 5). Diagnosis of pancreatic trauma in 17 patients was made through ultrasonography and/or CT scan. In 4 patients, the diagnosis was made intraoperatively. Associated injuries were splenic (n = 6), hepatic (n = 5) and duodenal (n = 5). Thirteen patients had only medical treatment and 8 patients required laparotomy. The two groups were comparable according to the rate of high grade pancreatic lesions. RESULTS: Two complications, a pancreatic fistula and a pseudocyst, occurred in the operative group and improved spontaneously. One death due to a head trauma, one acute pancreatitis and seven pancreatic pseudocysts (six required percutaneous drainage), occurred after medical treatment. The mean hospital stay, shorter after medical treatment, was not significantly different between the two groups (26 days vs 32 days). During the follow-up, no late complications have been observed. CONCLUSION: Traumatic pancreatic injuries are rarely lethal but are often associated with other intra-abdominal injuries. Conservative treatment is advocated for grade 1 to 4 isolated pancreatic injuries. This conservative approach may be associated with the development of post-traumatic pancreatic pseudocysts which are easily cured by percutaneous drainage.

Accidental Falls↗

PubMed2001

Nitric oxide in rheumatology.

Nitric oxide (NO) is attracting considerable interest because it mediates many functions. This gas is ubiquitously produced in the body by three enzymes, called NO synthases. Two NO synthases are constitutively expressed, one in the nervous system and the other in the blood vessels, where it regulates tissue perfusion. The third NO synthase can be induced by several stimuli (bacterial endotoxins, cytokines), most notably in inflammatory cells and chondrocytes. The effects of NO produced by the inducible NO synthase range from T-cell response modulation to formation of free radicals responsible fortissue damage and cartilage matrix degradation. Administration of NO synthase inhibitors in animal models of arthritis yields ambiguous effects, often with prevention of arthritis, but sometimes with worsening of established arthritis. The data available to date do not support the use of such inhibitors in the treatment of human arthritis.

Animals↗

PubMed2001

Portal venous decompression with H-type mesocaval shunt using autologous vein graft: a North American experience.

BACKGROUND/PURPOSE: Portal hypertension in children often is caused by prehepatic venous obstruction or intrahepatic fibrosis without cirrhosis. This situation is uniquely amenable to shunting; this report details the experience of 3 North American centers with an H-type mesocaval shunt using autologous vein, which has been widely used in European centers. METHODS: Retrospective chart review was conducted of records from 1980 through 1999 at 3 North American institutions. Charts were reviewed for etiology of portal hypertension, diagnostic workup, preoperative management, operative results and complications, postoperative shunt patency, patient well-being, and eventual need for liver transplantation. RESULTS: Twenty patients were identified with prehepatic causes of venous obstruction undergoing shunt therapy. Eleven had portal venous thrombosis or cavernous transformation. Of these, 3 had umbilical catheters placed in the neonatal period. Five children had American-Indian cirrhosis, 1 had congenital hepatic fibrosis, and 3 had hepatic fibrosis associated with polycystic kidney disease. Patients presented at a median age of 3.7 years and underwent follow-up for an average of 4.3 years after surgery. These patients had an average of 3.6 bleeding episodes, (with 3.9 attempts at sclerotherapy) and received 3 units of blood preoperatively. Average age at operation was 8 years, average weight was 30 kg, and perioperative blood requirement was 200 mL. In general, patients did well postoperatively; 2 patients required reoperation for lymphatic leaks, and there was 1 death caused by a leaking G-tube, unrelated to shunt functioning. Two patients had transient encephalopathy postoperatively, and 1 patient had severe pancreatitis. All shunts remain patent, with good function and no further bleeding. CONCLUSIONS: These results are encouraging, and we would suggest that the H-type mesocaval shunt utilizing autologous vein be considered for wider use in pediatric patients with prehepatic cause of portal hypertension. An algorithm for the work-up of pediatric patients with variceal bleeding is presented, with the recommendation that shunt surgery be considered early in patients with a prehepatic or fibrotic causes of portal hypertension.

Algorithms↗

PubMed2001

Surgical resection and chemotherapy improve survival rate for patients with hepatoblastoma.

BACKGROUND: The authors reviewed retrospectively their experience in 30 children with hepatoblastoma (HB). Despite an increased trend in the incidence of HB during the last 2 decades, an encouraging cure rate has been achieved with complete resection of the tumor and chemotherapy before or after surgery with cisplatin plus doxorubicin (Adriamycin) or cisplatin plus vincristine plus 5-Fluorouracil. RESULTS: There were 10 female and 20 male patients. For the period from 1963 to 1980 there were 8 patients, and for the period from 1981 to 1998 there were 22 patients. Their mean age at surgery was 16 months (range, 3.5 months to 5.5 years). Tumors were localized to the right lobe in 10 (42%), to the left lobe in 7 (29%), and in both lobes in 7 (29%) of the resected patients. Tumors were greater than 10 cm in size in 16 (67%) of these patients. Twenty-four patients (80%), underwent liver resection before or after chemotherapy. One patient (3%) with an unresectable tumor received chemotherapy and a liver transplant. In 5 patients (17%) the hepatic involvement was too extensive for resection. The types of resection performed were right lobectomy in 7, left lobectomy in 6, right trisegmentectomy in 8, left trisegmentectomy in 2, and middle hepatectomy in 1. The overall survival rate for 35 years of the study was 60% (18 of 30). With the association of surgery and chemotherapy (1981 through 1998) survival rate is 82% (14 of 17). Overall median follow-up in our study is 8 years (range, 2.5 to 24 years). CONCLUSIONS: There has been a dramatic improvement in the results of treatment of hepatoblastoma. Formerly, only 25% to 30% of patients were cured, whereas today, with combination of chemotherapy and surgery, 75% to 80% may be cured.

Actuarial Analysis↗

PubMed2001

Abdominal injuries associated with thoraco-lumbar fractures after motor vehicle collision.

PURPOSE: The goal of the current study was to evaluate the risk of intraabdominal injury in children who sustained spinal fractures in a motor vehicle collision (MVC). METHODS: Between 1980 and 1999, 48 patients, 24 girls and 24 boys, with a mean age of 12.8 years (range, 4 to 17) were reviewed. Twenty-nine were rear seat passengers, 12 front seat, and 7 unknown. Fifty-eight percent wore a seat belt. Thirty fractures involved the lumbar spine, 12 the thoracic, and 6 combined. Computed tomography (CT) scan, abdominal ultrasound, and peritoneal lavage were used to screen for abdominal injuries. RESULTS: Twenty-two of 48 patients had an intraabdominal injury. Eighteen (38%) required an early (<24 hours; n = 12) or delayed (n = 6) therapeutic laparotomy. Fourteen patients were rear seat passengers, 15 wore a seat belt, and 13 had an abdominal wall ecchymoses (AWE). They were 17 lumbar fractures (13 Chance) and one thoracic. The most common findings at laparotomy were hollow viscus injury (n = 12), mesenteric tear (n = 9), and solid organ injury (n = 8). Seventy-two percent of patients presenting with a lumbar fracture and AWE needed a therapeutic laparotomy. The overall survival rate was 98% with only 1 death. The mean hospital stay was 22.4 days. In this study, 38% of patients presenting with a spinal fracture required laparotomy, 68% of whom had simultaneous lumbar fracture and AWE. CONCLUSION: In light of these results, the authors propose that laparoscopy or laparotomy should be strongly considered in patients sustaining lumbar fracture and AWE after MVC. J Pediatr Surg 36:760-762.

Abdominal Injuries↗

PubMed2001

Crystallization and preliminary X-ray diffraction studies of FHA domains of Dun1 and Rad53 protein kinases.

Forkhead-associated (FHA) domains are modular protein-protein interaction domains of approximately 130 amino acids present in numerous signalling proteins. FHA-domain-dependent protein interactions are regulated by phosphorylation of target proteins and FHA domains may be multifunctional phosphopeptide-recognition modules. FHA domains of the budding yeast cell-cycle checkpoint protein kinases Dun1p and Rad53p have been crystallized. Crystals of the Dun1-FHA domain exhibit the symmetry of the space group P6(1)22 or P6(5)22, with unit-cell parameters a = b = 127.3, c = 386.3 A; diffraction data have been collected to 3.1 A resolution on a synchrotron source. Crystals of the N-terminal FHA domain (FHA1) of Rad53p diffract to 4.0 A resolution on a laboratory X-ray source and have Laue-group symmetry 4/mmm, with unit-cell parameters a = b = 61.7, c = 104.3 A.

Animals↗

PubMed2000

Caspase-8 specificity probed at subsite S(4): crystal structure of the caspase-8-Z-DEVD-cho complex.

Caspase-8 is an initiator enzyme in the Fas-mediated pathway of which the downstream executioner caspase-3 is a physiological target. Caspases are cysteine proteases that are specific for substrates with an aspartic acid residue at the P(1) position and have an optimal recognition motif that incorporates four amino acid residues N-terminal to the cleavage site. Caspase-8 has been classified as a group III caspase member because it shows a preference for a small hydrophobic residue at the P(4) substrate position. We report the X-ray crystallographic structure of caspase-8 in complex with benzyloxycarbonyl-Asp-Glu-Val-Asp-aldehyde (Z-DEVD), a specific group II caspase inhibitor. The structure shows that the inhibitor interacts favourably with the enzyme in subsite S(4). Kinetic data reveal that Z-DEVD (K(i) 2 nM) is an almost equally potent inhibitor of caspase-8 as the specific group III inhibitor Boc-IETD-aldehyde (K(i) 1 nM). In view of this finding, the original classification of caspases into three specificity groups needs to be modified, at least for caspase-8, which tolerates small hydrophobic residues as well as the acidic residue Asp in subsite S(4). We propose that the subsite S(3) must be considered as an important specificity-determining factor.

Binding Sites↗

PubMed2000

Animal models of the spondyloarthropathies.

Several lines of rats transgenic for human leukocyte antigen (HLA)-B27 spontaneously develop a multisystemic inflammatory disease resembling human spondyloarthropathies. This disease is mediated by cells of the immune system and is dependent on the presence of a normal bacterial flora. Both antigen-presenting cells expressing high levels of HLA-B27 and T cells appear to be of importance in the pathogenesis of this model. HLA-B27 transgenic/b2- microglobulin deficient mice also develop arthritis, under the influence of the bacterial flora. In both types of model, CD8+ T cells appear to be unnecessary, arguing against the "arthritogenic peptide" hypothesis.

Animals↗

PubMed2000

Repair of the huge umbilical hernia in black children.

Surgical repair of large umbilical hernias may present a challenging surgical problem. The currently described surgical techniques often yield disappointing results. The authors describe a new technique that allows for the repair of the fascial defect and the creation, with the use of a square cutaneous flap, of a neoumbilicus with sufficient depth and a good cosmetic appearance.

Black People↗

PubMed2000

Past and future of biliary atresia.

BACKGROUND: With the advent of liver transplantation the outcome of children with biliary atresia (BA) has improved. Is Kasai hepatic portoenterostomy (KHPE) still a valuable option for the treatment of these patients? METHODS: From 1974 to 1998, 77 patients with biliary atresia have been treated at our institution: 50 girls and 27 boys. RESULTS: Seventy-four patients had a KHPE, and 3 patients had no KHPE because of delay in diagnosis. A total of 65 of 74 patients (88%) had undergone KHPE type I, 4 patients (5.4%) KHPE type II, 3 patients (4%) had a Suruga modification, and 2 patients (2.6%) had a portocholecystostomy. Among the 74 patients, 11 were lost to follow-up and their cases were considered failures. Seventeen of our patients are alive at long-term follow-up after KHPE. Among the 77 patients, 33 (43%) had an orthotopic liver transplantation (OLT). Successful KHPE patients underwent transplant at a mean age of 9 years, and KHPE failed at a mean age of 11 months. A total of 25 of 77 (32%) of patients are alive thanks to OLT. In the cohort, the overall survival rate for the KHPE plus OLT is 42 of 77 (55%). Mortality and morbidity rates were more frequent among the younger patients who had early OLT after KHPE failure. In our series, overall survival rate was improved when the patient had a successful KHPE (P < .001). CONCLUSIONS: Kasai hepatic portoenterostomy (KHPE) continues to be a valuable procedure in the treatment of infants with biliary atresia (BA). Successful KHPE permits transplantation at an age at which mortality and morbidity are decreased leading to a better outcome.

Biliary Atresia↗

PubMed1999

The three-dimensional structure of caspase-8: an initiator enzyme in apoptosis.

BACKGROUND: In the initial stages of Fas-mediated apoptosis the cysteine protease caspase-8 is recruited to the cell receptor as a zymogen (procaspase-8) and is incorporated into the death-signalling complex. Procaspase-8 is subsequently activated leading to a cascade of proteolytic events, one of them being the activation of caspase-3, and ultimately resulting in cell destruction. Variations in the substrate specificity of different caspases have been reported. RESULTS: We report here the crystal structure of a complex of the activated human caspase-8 (proteolytic domain) with the irreversible peptidic inhibitor Z-Glu-Val-Asp-dichloromethylketone at 2.8 A resolution. This is the first structure of a representative of the long prodomain initiator caspases and of the group III substrate specificity class. The overall protein architecture resembles the caspase-1 and caspase-3 folds, but shows distinct structural differences in regions forming the active site. In particular, differences observed in subsites S(3), S(4) and the loops involved in inhibitor interactions explain the preference of caspase-8 for substrates with the sequence (Leu/Val)-Glu-X-Asp. CONCLUSIONS: The structural differences could be correlated with the observed substrate specificities of caspase-1, caspase-3 and caspase-8, as determined from kinetic experiments. This information will help us to understand the role of the various caspases in the propagation of the apoptotic signal. The information gained from this investigation should be useful for the design of specific inhibitors.

Amino Acid Sequence↗

PubMed1999

Pleuropulmonary blastoma: a rare pathology with an even rarer presentation.

BACKGROUND: Pleuropulmonary blastoma is among the rarest tumors of childhood. Three types have been described: cystic, solid, and mixed. To date, bilateral disease has not been documented. METHODS AND RESULTS: A 5-week-old girl presented with a history of fever. Chest x-ray showed bilateral diffuse cystic lesions. Bowel obstruction developed that required laparotomy. Multiple small bowel polyps were resected. The patient was readmitted 4 months later with deteriorating respiratory status. She underwent sequential thoracotomies for resection of multiple bullae under high-frequency oscillatory ventilation. Small bowel polypectomies were again required because of obstruction. Lung lesions were compatible with pulmonary blastoma but could not be correlated with intestinal polyposis. Bilateral cystic renal lesions were seen on ultrasound scan. Her disease progressed, despite chemotherapy, with the appearance of metastatic iris lesions. She again underwent laparotomies for multiple recurrent generalized small bowel polyps that were causing obstruction. Expanding renal cysts affected kidney function, and she died at 14 months of age. CONCLUSIONS: The rare association between pleuropulmonary blastoma and Wilms' tumor or nephroblastomatosis is known but rarely reported. Lacking pathological evidence, we can only speculate that this was the case. We have been unable to demonstrate any histological association between the renopulmonary and digestive lesions. Despite many unanswered questions, we are likely dealing with a "syndrome" of sorts with a dire outcome, despite aggressive treatments.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed1999

[Congenital absence of portal vein in a girl with biliary atresia treated with liver transplant].

The congenital absence of the portal vein is a rare malformation, which has been generally discovered in association with another anomalies like a cardiac, gastrointestinal or genitourinary defects. With portal hypertension and hepatic cirrhosis, this anomaly is similar to spontaneous porto-systemic derivation, and for that not collateral venous drainage is present. In these patients, total interruption of mesentaric venous drainage during procurement of liver transplant produce a very important bowel and mesenteric edema, which can promote an injert fatal evolution. The authors present the first paediatric liver transplant, in a patient with portal venous agenesia, with de piggy-back technique was done and this complication was obviated, and a review of the literature about this issue is done.

Biliary Atresia↗

PubMed1998

Spleno-caval shunt in children using internal jugular vein graft: a case report.

Several techniques for decompression of portal hypertension have been described. The spleno-caval shunt is an easy and safe technique described in adult patients. However, the procedures described in adults are not adapted to children. We report an adaptation of this technique in a child, using the internal jugular vein as an interposition graft for relief of portal hypertension.

Child, Preschool↗

PubMed1998

Circulating endotoxin during initial antibiotic treatment of severe gram-negative bacteremic infections.

The impact of antibiotics on total endotoxemia and circulating tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, and IL-8 in 18 patients with severe bacteremic sepsis or septic shock due to gram-negative species was investigated. Endotoxemia, TNF-alpha, IL-6, and IL-8 were assayed before (H0) and 1 h (H1) and 4 h (H4) after the first antibiotic infusion. Endotoxemia decreased from H0 (median, 0.4 EU/mL; interquartile interval, 0.09-1.23) to H1 (median, 0.19 EU/mL; interquartile interval, 0.07-0.75; P = .03) and remained stable between H1 and H4 (median, 0.12 EU/mL; interquartile interval, 0.09-0.30; P = .4). IL-6 levels fell between H0 and H4 (P = .01) and between H1 and H4 (P = .03). IL-8 was higher at H0 than at H1 (P = .04) and at H4 (P = .01). These results suggest that endotoxemia is not increased by antibiotherapy of severe gram-negative bacteremia.

Adult↗

PubMed1998

[Bartonella quintana endocarditis. Aortic localization and mitral valve abscess].

Bartonella Quintana is an exceptionally rare cause of endocarditis. The frequency of this condition is increasing and is probably underestimated because of the difficulty in diagnosing. The clinical context is that of socially deprived classes, the agent of transmission of the germ being body lice. The commonest valve affected is the aortic valve. This infection may also give rise to a mitral annulus abscess, as in this particular case. The diagnosis should be suspected in all cases of endocarditis with negative blood cultures in socially deprived patients as special diagnostic methods are required. Bartonellosis serology and drainage of effusions to perform a Gimenez stain to show intra-cellular bacteria and a polymerase chain reaction to sequence the nucleic acids, will give an accurate diagnosis. Similarly, the operative specimens should be sent to a specialised department for the culture of these bacteria (in France, the Marseille Ricketsioses Institute). The treatment of Bartonella endocarditis is very controversial. The usual recommendations are an association of betalactamines and an aminoside for one month and macrolides or tetracyclines. There is lack of consensus about follow-up. It would seem prudent to perform a clinical examination to search for a relapse of the infection and monthly serologies until they return to normal values.

Abscess↗

PubMed1997

Intrahepatic biliary-enteric bypass for complete extrahepatic biliary obstruction in children.

Intrahepatic biliary-enteric anastomosis is rarely practiced in pediatric surgery. The authors report on two children who have been successfully treated using this method. First described by Longmire and Sandford in 1948, intrahepatic biliary-enteric anastomosis is possible in children. This procedure is only indicated as a last recourse for circumstances in which the extrahepatic biliary tree is completely obstructed.

Anastomosis, Roux-en-Y↗

PubMed1997

Childhood adrenocortical tumors: case series and reevaluation of prognosis--a 24-year experience.

Adrenocortical neoplasms are rare in childhood and adolescence. The prognostic significance of tumor size, weight, and histological grade are still very much unclear. Eleven patients, (3 boys, 8 girls), with a median presentation age of 7 years (range, 0.8 to 16 years) were identified. Six presented with virilizing symptoms, two with cushingoid symptoms, one with both, and two others had nonspecific symptoms. The interval between onset of symptoms and diagnosis was an average of 18 months (median, 8 months). Hormonal profile correlated well with clinical presentation in nine patients. Two patients with nonspecific symptoms had an aldosterone-producing lesion and an androgen-secreting tumor. Ten patients underwent complete surgical excision, with one intraoperative spillage. Median tumor weight was 94.5 g (range, 4 to 750 g). Three lesions were less than 5 cm in maximal width, six were between 5 and 10 cm, and two were greater than 10 cm. Two tumors had capsular or vascular invasion. Three patients received chemotherapy: one who had inoperable metastatic disease, and two based on clinical and histopathologic findings. Ten patients are doing well, without evidence of recurrent disease with a median follow-up of 3 years (range, 9 months to 15 years), eight patients have been followed up for more than 2 years. The medically treated patient who had metastatic disease died 3 years after diagnosis. A review of the pediatric literature, in some cases, indicates that larger tumors have a worse prognosis, while other investigators claim histological grade is more important. The authors' results do not support these conclusions, but rather suggest that in the pediatric population, when excision is complete, guarded optimism is warranted even with tumors larger than 5 cm. Addendum: Since submission of the manuscript, patient 4 has been operated on twice for local recurrences 13 and 16 months after the initial surgery. She was the only patient in the series to have an intraoperative capsular tear. All other surgical patients remain free of disease.

Adolescent↗