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Biomedical subjects

J C McDonald

Publications and source records attributed to J C McDonald.

At least 19 recordsLinked to original sources
PubMed1996

Association of serum concentration of soluble class I HLA with HLA allotypes.

We correlated serum concentrations of soluble class I HLA antigens (S-HLA-I) with HLA allotypes in 82 unrelated Caucasian and 58 unrelated African-American putatively normal subjects, as well as in 31 individuals with stable, normally functioning liver transplants. Caucasian and African-American subjects with HLA-A23 or HLA-A24 were high secretors of S-HLA-I. We also observed that some HLA-A allotypes associated with high serum concentrations of S-HLA-I were ethnicity specific. HLA-A33 was associated with high S-HLA-I secretion in African-Americans but not in Caucasians. HLA-A29 was associated with high S-HLA-I secretion in Caucasians but not in African-Americans. All liver transplant recipients studied who were high secretors of S-HLA-I postoperatively carried HLA-A24 or HLA-A29. (There were no HLA-A33 or HLA-A23 allotypes in this group.) The "secretor genes," however, may be autogenous or allogenic (i.e., either donor or recipient HLA-A24 or HLA-A29 resulted in the observed high secretor status in liver transplant recipients after transplantation). It is noteworthy that serum S-HLA-I concentrations were low in all subjects with HLA-A2 regardless of whether the HLA-A2 was of recipient or donor origin. This finding suggests that HLA-A2 could have a suppressive effect on S-HLA-I secretion.

Black People↗
PubMed1996

Endoscopic diagnosis and management of biliary complications following orthotopic liver transplantation.

Nonoperative management of biliary complications (BC) with endoscopic retrograde cholangiopancreatography (ERCP) is a natural sequel to the emergence of choledochocholedochostomy as the preferred biliary reconstruction for orthotopic liver transplantation (OLT). Overall, therapeutic ERCP's efficacy for posttransplant BC is difficult to assess because most published data are retrospective, anecdotal, or in abstract form, and there are no prospective, randomized studies. Thus, endoscopic management of posttransplant BC must be individualized. While T-tube-related late bile leaks and ductal calculi are amenable to endoscopic therapy, its efficacy for strictures is more difficult to define. Refined surgical technique has prevented many unifocal anastomotic lesions, while multifocal strictures (for which endoscopic therapeutic experience is minimal) are increasingly prevalent. Whether endoscopic sphincterotomy is appropriate for posttransplant sphincter of Oddi dysfunction is controversial, because the disorder may be transient and the risk significant. Multicenter, prospective studies are needed to determine more accurately the optimal role of endoscopic therapy after OLT.

Biliary Tract Diseases↗
PubMed1996

A retrospective study of the efficacy of transjugular intrahepatic portosystemic shunts.

Transjugular intrahepatic portosystemic shunts (TIPS) are being used increasingly for complications of portal hypertension, including active and recurrent variceal hemorrhage and intractable ascites, as well as for portal decompression in patients awaiting orthotopic liver transplantation. We reviewed the initial 2-year experience with TIPS at Louisiana State University Medical Center-Shreveport and Willis-Knighton Medical Center, Shreveport, Louisiana, which involved 31 patients. Clinical findings (with some patients having more than one finding) revealed that 16 per cent (five) of the patients had active hemorrhage; 61 per cent (19), multiple episodes of (recurrent) variceal hemorrhage; and 48 per cent (15), ascites. The mean follow-up period was 6.2 months, with a patient mortality of 13 per cent. Results showed that in 87 per cent (27 of 31) of patients the TIPS procedure was successfully placed. There was 100 per cent control of active variceal hemorrhage (five patients) and ascites (12 patients; excludes three patients who died). Rebleeding occurred in 18 per cent (four of 22) of patients, all related to stenosis or occlusion of the TIPS. The overall incidence of occlusion and stenosis was 11 per cent and 22 per cent, respectively. Seventy-seven per cent (seven of nine) of the patients experiencing the latter complications underwent successful angioplasty or revision of their TIPS. The results of our experience indicate that TIPS placement can be performed successfully with low procedural morbidity. The procedure is effective in controlling active variceal hemorrhage refractory to endoscopic sclerotherapy. The use of TIPS may be particularly beneficial for patients who are either awaiting liver transplantation or poor candidates for surgical shunt procedures. TIPS may not be a long-term solution for patients with portal hypertension, given the current rates of occlusion and stenosis.

Adult↗
PubMed1995

The risks, benefits, and costs of expanding donor criteria. A collaborative prospective three-year study.

The study purpose was to identify risks, benefits and costs associated with an expanded donor protocol. The protocol design evaluated organs rescued using expanded donor criteria and weighed all costs associated with doing so. Costs were measured against conditions experienced with expanded and traditional criteria and recipient outcome. Traditional donors were between 5 and 55, with negative serologies, and no history of hypertension or diabetes. "Expanded donors" were between 55 and 75 or less than 5, with a history of hypertension, diabetes and/or sero-positive for Hepatitis C. During this study 73 donors met criteria from which 200 organs were transplanted. Defined costs and outcomes for recipients were tracked. Using expanded criteria: costs averaged 20% more per organ; OPO personnel spent an average of 6 hours more time on-site; an additional 12-14 hours in placement activity; and average organs per donor decreased. Heart patient and graft survival rates for traditional and expanded donor organs were comparable. Kidney patients transplanted from this pool experienced a decrease in patient (P = .14) and a significant decrease in graft (P = .02) survival rates. Patient (P = .05) and graft (P = .01) survival rates were significantly lower in liver patients transplanted with expanded donor organs. Two hundred transplants occurred using expanded donor criteria. Costs for the OPO increased appreciably. Heart and kidney utilization from these donors seems justified. It is thought that liver recipients' results were due to utilizing them in sicker patients. Recovery of organs from donors using expanded criteria appears to be a reasonable way of increasing organ supply.

Adolescent↗
PubMed1995

A critical review of the Couinaud technique of hepatic resection.

The Couinaud technique of left hepatic lobectomy involves the isolation and division of portal vein, hepatic artery, and biliary tributaries as a unit within the liver parenchyma. It saves time and minimizes blood loss by virtue of the common investment of the portal structures in a thick connective tissue sheath. Right hepatic lobectomy can be performed in a similar manner based on the same assumption that the biliary and vascular tributaries maintain a constant anatomic relationship with one another. We describe a patient who underwent right hepatic lobectomy by the Couinaud technique who (in retrospect) had congenital absence of a left hepatic duct. Because small bile ducts from the left lobe drained into the right hepatic duct deep to the sight of resection, obstructive jaundice resulted postoperatively, necessitating orthotopic liver transplantation. Presently, the patient is doing well 1 year after transplantation. When the Couinaud technique is used in the setting of a biliary anatomic variant, the results can be disastrous. This case illustrates that the Couinaud technique is unsafe unless biliary anatomic variants are excluded prior to hepatic lobectomy.

Bile Ducts↗
PubMed1995

SWORD '94: surveillance of work-related and occupational respiratory disease in the UK.

Chest and occupational physicians participating in SWORD are estimated to have seen some 3300 cases of work-related respiratory disease in 1994, similar to the totals for 1992-1993. Occupational asthma was the single most frequent diagnosis (941 cases), but asbestos exposure was considered the cause in 1529 cases of diseases of long latency. Large-scale follow-up studies showed (i) that most patients with occupational asthma failed to recover and that half had left their employer, and (ii) that many patients had long-term respiratory illness including asthma following inhalation accidents. Over the six years of the scheme there have been slight changes in attributed agents for occupational asthma and in the frequency of various diagnoses; for example, there has been a gradual reduction in reports of pneumoconiosis. A decline with birth cohort in the proportion of mesotheliomas in men employed in shipyards is shown, with some evidence of a compensatory trend in construction trades.

Adult↗
PubMed1995

Sequential endoscopic/laparoscopic management of sickle hemoglobinopathy-associated cholelithiasis and suspected choledocholithiasis.

We reviewed the medical records of 17 patients with sickle hemoglobinopathy-associated cholelithiasis who were candidates for laparoscopic cholecystectomy (LC) between 1991 and 1994. Eight patients with suspected choledocholithiasis (CDL) were identified, all of whom had preoperative endoscopic retrograde cholangiopancreatography (ERCP), which revealed CDL in 3 patients (18%), all of whom had endoscopic ductal clearance. Choledocholithiasis was suspected because of hyperbilirubinemia or serum liver enzyme abnormalities. Incremental hyperbilirubinemia exceeding "baseline" values by > 5 mg/dL was the best predictor of CDL. Subsequent LC was successful with discharge within 2 days of LC in all but one patient, who was converted to open cholecystectomy. This small series suggests that in sickle hemoglobinopathy patients with cholelithiasis (1) CDL is relatively common among patients with an increase above baseline hyperbilirubinemia, (2) bile duct dilatation, alkaline phosphatase, and serum aminotransferase levels are poor predictors of CDL, and (3) sequential endoscopic/laparoscopic management of cholelithiasis and suspected CDL is successful.

Adult↗
PubMed1995

Soluble class I HLA antigens in patients with rheumatoid arthritis and their families.

OBJECTIVE: To study Class I soluble HLA in black patients with rheumatoid arthritis (RA) and their families, and to compare the findings to a group of healthy families of the same racial background. METHODS: ELISA was developed measure soluble HLA Class I (sHLAI) in the serum of 25 patients with RA. Family studies were performed in seven patients with RA and their 28 first degree relatives. These family studies were compared to similar measurements for 66 members of 13 healthy families. RESULTS: Mean sHLAI values were higher in patients with RA than those observed in healthy black individuals. Patients with RA were characterized by elevated serum HLAI, while no change was observed between patients with RA positive or negative for rheumatoid factor. The relatives of patients with RA had high concentrations of sHLAI, compared to families without RA. Highest serum concentrations of sHLAI were found in individuals who were HLA-A23 or HLA-Aw33 positive. CONCLUSION: sHLAI may play a role in the pathophysiology of RA, and there is an association between either augmented release or production of sHLAI and specific HLA allotypes.

Alleles↗
PubMed1994

Soluble HLA class II concentrations in normal individuals and transplant recipients. Comparison with soluble HLA class I concentrations.

We developed an ELISA to quantify soluble HLA class II (S-HLA-II) in 702 sera obtained from normal subjects, patients with end-stage renal disease, and recipients of renal, hepatic, and cardiac transplants. Concentrations of S-HLA-II were detectable in 124 of 126 normal individuals. The distribution of normal values described a monophasic curve with a skewed distribution. In transplant recipients, there were no differences between preoperative and posttransplant values, but values in liver patients were significantly higher than in kidney patients, and values for heart patients were lowest of all groups. There were periodic variations in concentrations in individual patients, but these were unrelated to rejection, infection, or any other apparent clinical event. S-HLA-II was consistently present in the urine. All of these observations contrast with previous observations concerning soluble HLA class I (S-HLA-I) molecules, which were almost the precise reverse. It seems likely that these clear differences in S-HLA-II and S-HLA-I concentrations relate to different physiologic processes in either production, function, or elimination.

Graft Rejection↗
PubMed1994

Transplantation and quality of care for end-stage renal disease: 1993.

We describe a group of renal transplant recipients whose allografts are in general considered to be successful statistically, but who are not greatly benefitted clinically. Grafts in these recipients survive somewhat longer than 6 months, but generally less than 3 years. Many of these individuals are chronically ill. They have many hospitalizations, experience most of the complications associated with transplantation, and incur more mortality and less benefit. Research initiatives need to be focused on this group of patients. A major study of more sensitive methods of detecting presensitization might be beneficial.

Adult↗
PubMed1994

SWORD '93. Surveillance of work-related and occupational respiratory disease in the UK.

Some 3500 new cases of occupational respiratory disease are estimated to have been seen annually by SWORD participants in 1992 and 1993 with little important difference between the two years. As the number of new cases recognized and reported by chest physicians is close to complete, the estimated incidence is essentially correct. The pattern of disease which clearly emerges shows that at least half is attributable to asbestos exposure, despite the fact that lung cancer from this cause may be under-reported. Benign pleural disease comprises a large proportion of the cases, the long-term implications of which are unknown. Almost 40% of the cases reported are of occupational asthma or inhalation accidents, both due to a very large number of different agents and affecting many and varied occupations. These cases are preventable providing their occupational aetiology is recognized and appropriate measures of control are intensified.

Aged↗
PubMed1994

Work-related respiratory disease in the United Kingdom, 1989-1992: report on the SWORD project.

The objective of this project is the creation of a reliable and cost-effective national system of surveillance for work-related respiratory disease as a basis for control and simple epidemiological research. With the voluntary participation of almost 800 chest and occupational physicians from throughout the UK, newly diagnosed cases of respiratory illness thought to be due to occupational factors have been reported regularly since January 1989. Since January 1992, reports from chest physicians have been submitted monthly by a core group with special interest in occupational lung disease (n = 32) and rotating random samples of the remainder. Between 1989 and 1991, 5576 new cases were reported, of which half were diseases of long latency mainly due to asbestos, 28% were occupational asthma, and the rest were divided between inhalation accidents (10%) and a variety of other acute diseases (14%). Disease incidence rates, with denominators from the Labour Force Survey, showed a very high risk of asthma among paint sprayers, chemical and food processors, laboratory staff, plastics and metal treatment workers, and in welding and electronic assembly. Some of the same groups also experienced high rates of inhalation accidents and bronchitis. The risk of diseases of long latency, using denominators from the 1961 census, was highest in shipyard and dock workers, miners and construction workers. The SWORD scheme has provided estimates of disease incidence not previously available, has encouraged awareness of occupational factors among chest physicians, has assisted those responsible for prevention and control, and has demonstrated the feasibility of this approach to surveillance.

Adolescent↗
PubMed1994

Recent advances in the management of gallstones.

Demands for less invasive, more cost-effective therapy have revolutionized the management of gallstones over the past 10 years. There are no reliable methods of permanently reversing the pathophysiologic defects that cause gallstones. Open cholecystectomy (OC), the gold standard for managing symptomatic cholelithiasis, has been largely replaced by laparoscopic cholecystectomy (LC), which has the advantages of a minimal hospital stay and quicker return to work. Other adjunctive therapies, limited in applicability to selected patients, include oral bile acid therapy (BAT), dissolutional agents, and extracorporeal shock wave lithotripsy. Choledocholithiasis (CDL), formerly managed exclusively with surgical common duct exploration, is increasingly treated with therapeutic biliary endoscopy. Methods of laparoscopic common bile duct exploration are being developed. Optimal algorithms for applying these techniques to patients undergoing LC are evolving. In a sense, the solution to all, or certainly most, gallstones now can be seen through a scope.

Bile Acids and Salts↗