Search PubMed⌕ Search

Biomedical subjects

J P Welch

Publications and source records attributed to J P Welch.

At least 19 recordsLinked to original sources
PubMed1992

Unbalanced translocation of chromosome 3p in Wilms' tumor.

Genetic studies in Wilms' tumor have most commonly shown a deletion involving band 13 on the p arm of chromosome 11 in association with aniridia. Structural rearrangements of chromosome 3p have been found in carcinoma of renal cell and lung origin but have not been previously reported in Wilms' tumors. We present two phenotypically normal, unrelated patients with Wilms' tumors, one of which was bilateral, in which cytogenetic analysis of the tumors showed an unbalanced translocation of the p arm of chromosome 3. Two biopsies were done in the patient with bilateral Wilms' tumor. The first biopsy specimen showed a translocation between chromosome 3 and 13 with partial trisomy of 3p and loss of material from 13q. The second biopsy three and a half months later again showed trisomy of chromosome 3p. The unilateral Wilms' tumor showed trisomy of 3p with partial loss of 7p. Neither patient showed a constitutional chromosomal abnormality and neither tumor showed any cytogenetic abnormality involving chromosome 11p. Quantitative DNA analysis was performed in the tumors of both patients. The bilateral Wilms' tumor was nearly diploid with a DNA index of 1.284 (mean ploidy, 2.45; SD, 0.854) while the unilateral Wilms' tumor was aneuploid with a DNA index of 1.531 (mean ploidy, 3.35; SD, 0.976). DNA analysis results are discussed in relationship to the chromosome abnormality seen on the karyotype analysis. These cytogenetic findings suggest that genetic oncogenesis in Wilms' tumor is heterogenous.

Aniridia↗
PubMed1992

A pseudodeficiency allele common in non-Jewish Tay-Sachs carriers: implications for carrier screening.

Deficiency of beta-hexosaminidase A (Hex A) activity typically results in Tay-Sachs disease. However, healthy subjects found to be deficient in Hex A activity (i.e., pseudodeficient) by means of in vitro biochemical tests have been described. We analyzed the HEXA gene of one pseudodeficient subject and identified both a C739-to-T substitution that changes Arg247----Trp on one allele and a previously identified Tay-Sachs disease mutation on the second allele. Six additional pseudodeficient subjects were found to have the C739-to-T mutation. This allele accounted for 32% (20/62) of non-Jewish enzyme-defined Tay-Sachs disease carriers but for none of 36 Jewish enzyme-defined carriers who did not have one of three known mutations common to this group. The C739-to-T allele, together with a "true" Tay-Sachs disease allele, causes Hex A pseudodeficiency. Given both the large proportion of non-Jewish carriers with this allele and that standard biochemical screening cannot differentiate between heterozygotes for the C739-to-T mutations and Tay-Sachs disease carriers, DNA testing for this mutation in at-risk couples is essential. This could prevent unnecessary or incorrect prenatal diagnoses.

Amino Acid Sequence↗
PubMed1992

Acute mesenteric ischemia caused by isolated superior mesenteric artery dissection.

Isolated dissection of a peripheral artery is a rare event. Only 11 reports exist in the literature of dissection of the superior mesenteric artery, most of which have been fatal. This is the first documented case of the successful treatment of an acute ischemic event caused by a superior mesenteric artery dissection. In addition, the new technique of right gastroepiploic artery-to-superior mesenteric artery bypass is introduced as a satisfactory method of revascularization.

Acute Disease↗
PubMed1992

Management of benign, giant gastric ulcers.

Giant gastric ulcers (greater than 3 cm in diameter) have traditionally been considered to be refractory to medical therapy and were commonly thought to initially appear as life-threatening hemorrhage requiring emergent operative therapy. This study was undertaken to evaluate the results of medical and surgical treatment of benign, giant gastric ulcers and the validity of these traditional teachings. A retrospective review of 44 patients with giant gastric ulcers was performed to evaluate the results of medical and surgical therapy at Hartford Hospital (Hartford, CT). The majority of these patients received medical therapy. Over 57 per cent received only medical therapy, while 25 per cent received primary, operative therapy. Contrary to popular belief, the authors found that patients who received initial medical therapy did not have high morbidity or mortality rates. Therefore, while the necessity of early surgical intervention following perforation or in patients with signs of hemorrhagic shock can not be refuted, the authors conclude that medical therapy of benign, giant gastric ulcers is often effective and not unduly hazardous. Giant gastric ulcers, in and of themselves, are not an indication for surgery.

Adult↗
PubMed1979

Acute diverticulitis of the transverse colon with perforation: report of three cases and review of the literature.

Three cases of perforated diverticulitis of the transverse colon are added to 19 case reports in the English literature. This unusual disease entity is usually confused with acute appendicitis prior to operation and with carcinoma of the colon during the procedure. The cause of these diverticula is unclear, and their clinical presentation resembles that of right-sided diverticula. Segmental resection of the transverse colon together with end-to-end anastomosis is the treatment of choice, except in the occasional instance of a large intra-abdominal abscess, when anastomosis may be deferred.

Diverticulitis, Colonic↗
PubMed1979

Giant diverticular of the sigmoid colon: a review of differential diagnosis and operative management.

Giant sigmoid diverticula ("giant gas cysts," "giant sigmoid cysts") are an unusual complication of diverticulitis. We have recently seen two patients with such lesions, bringing the total number of reported cases to 48. Most patients are elderly and complain of abdominal pain or the presence of an abdominal mass. Air trapping by a ball-valve mechanism may be responsible for formation of the fibrous cysts. The gas-filled structures can usually be differentiated from other conditions by contrast studies. Excision of the cyst and adjacent colon with anastomosis can usually be accomplished safely under elective circumstances.

Adult↗
PubMed1979

Operative management of radiation injuries of the intestinal tract.

A review of forty cases of radiation-induced gastrointestinal injuries is presented. Based on this experience and reports in the literature, preoperative management and operative technics are discussed. The increased risk of radiation bowel injury is recognized in patients who have had previous operations. Preradiation contrast studies are advised to identify trapped loops of intestine in the pelvis. Small bowel resection is recommended with localized segments of disease. Bypass operations are preferable to avoid any extensive dissections. Bypass operations have anastomotic dehiscence rates similar to those of resections. Proctocolitis is usually managed by diverting colostomy, with resection in a few favorable cases or with treatment failures. Most rectovaginal fistulas are managed by permanent colostomy. Small bowel fistulas are best treated by bypass with partial or total exclusion rather than by primary resection. Vigorous preoperative and postoperative nutritional support and evaluation are vital because of the poor healing qualities of irradiated bowel. Multiple operative procedures should be anticipated because the natural history of radiation bowel injury is slowly progressive.

Aged↗
PubMed1979

The clinical correlation of an autopsy study of recurrent colorectal cancer.

The complete autopsies of 145 patients dying of colorectal cancer are reviewed. Isolated local or distant metastases are infrequent, compared to disseminated disease. Solitary local recurrences are most common after resection of rectal tumors. Right colon tumors spread to local and distant sites in 90% of autopsies, and to distant sites alone in 10%. Rectal tumors spread locally only in 25% of cases, to distant site alone in 25%, and to both in 50%. Regardless of the origin of the primary tumor, the liver is the most common site of metastasis, followed by the regional lymph nodes and the lungs. Two-thirds of the patients with right colon lesions died of liver metastases, and three-quarters of those with rectal tumors succumbed to disseminated disease. The current curative and palliative treatment of recurrent colorectal cancer in clinical medicine by surgery, radiotherapy, and chemotherapy is reviewed. It is suggested that an understanding of the anatomic patterns of cancer recurrence will increase in importance as advances in the modalities of treatment are made,

Aged↗
PubMed1978

Detection and treatment of recurrent cancer of the colon and rectum.

A series of 177 patients with recurrent colorectal cancer treated at the Massachusetts General Hospital is examined retrospectively. Two thirds of recurrences were observed by the second postoperative year, and 15% of patients were asymptomatic. Pelvic recurrences were usually attributable to rectal or sigmoid tumors, whereas right-sided carcinomas frequently spread to the liver. The commonest methods of clinical discovery of recurrence included findings of abdominal and pelvic masses, hepatomegaly, and positive chest films. The average survival after discovery of recurrence was only eleven months, but 23 patients having reresections for cure lived an average of thirty-three months. Seven patients (30%) undergoing reresection for cure represented probable cures. Chemotherapy with intravenous 5-FU provided poor palliation, but radiotherapy gave satisfactory relief of symptoms in approximately 50% of patients, particularly those with rectal or low colon lesions. A program of follow-up is offered since there is evidence that even the symptomatic patient may be well palliated or even cured by surgical resection of the recurrence or palliative therapy.

Aged↗
PubMed1978

Extrahepatic biliary obstruction by metastatic colon carcinoma.

Extrahepatic biliary obstruction can be caused by cancer metastatic from the colon to the lymph nodes adjacent to the bile duct. This report details our experience with eight such cases treated at the Massachusetts General Hospital in the last seven years. The interval between resection of the primary tumor and appearance of jaundice averaged 13 months. The location of the obstruction, preferably defined preoperatively by cholangiography, was low on the common duct in three cases and high in the porta hepatis in five. Relief of biliary obstruction was accomplished by biliary-enteric bypass (four cases), internal biliary stenting by permanent indwelling tube (two cases), or by portal irradiation (two cases). In addition to palliating the symptoms of obstructive jaundice, the period of comfortable survival appears to have been extended: the bypassed patients lived 13-38 months. Erosion of tumor into the duodenum, with resulting gastrointestinal hemorrhage, was an additional problem in three patients. Our overall experience illustrates the value of distinguishing this subgroup of patients from the larger number whose jaundice results from extensive liver metastases, and of treating aggressively those with extrahepatic biliary obstruction.

Adenocarcinoma↗
PubMed1978

Genetic and demographic aspects of Nova Scotia Niemann-Pick disease (type D).

All known cases of Nova Scotia Niemann-Pick Disease (type D) were traced to a couple born in Nova Scotia in the late 1600s. It is speculated that this disease is the result of a single mutation in one of the ancestors of Yarmouth County French Acadians. In the district where most affected children lived, the heterozygote frequency was estimated to be between 10% and 26%.

Computers↗
PubMed1977

Prevention of congenital rubella.

The vaccine of choice for rubella vaccination is considered to be RA 27/3, based on frequency of side effects, duration of immunity, antigenic potential and rate of reinfection by wild virus. The most appropriate individuals to be vaccinated are prepubertal schoolgirls and susceptible members of other high-risk groups, and a nationwide immunization program is suggested. Premarital determination of rubella-immune status should be mandatory for all women of childbearing age. A favourable cost/benefit ratio for rubella vaccination seems highly probable. The use of a rubella "fact sheet" to provide education and information for those at risk is strongly recommended.

Canada↗
PubMed1977

Isolated small bowel obstruction as the presenting feature of colonic disease.

Small intestinal obstruction without colonic dilation can be the mode of presentation in a variety of colonic diseases, including carcinoma, diverticulitis, and colitis. Plain abdominal roentgenograms may lead the unwary physician into errors of diagnosis and treatment by suggesting primary small bowel disease. Barium enema examination of the colon will keep the wary physician out of such traps. We describe five patients with small bowel obstruction who had a variety of colonic diseases diagnosed by barium contrast studies. If the reason for intestinal obstruction is not apparent and the need for emergency surgery is not compelling, we recommend an immediate contrast study of the colon to aid in evaluating possible colonic pathology.

Adult↗