PubMed Health⌕ Search

Biomedical subjects

D K Wong

Publications and source records attributed to D K Wong.

34 records · Page 2Linked to original sources
PubMed1995

Cytotoxic activity of V beta 8+ T cells in Crohn's disease: the role of bacterial superantigens.

In Crohn's disease, disease-related stimuli could alter the T cell receptor (TCR) repertoire. To examine the possibility that changes in function may occur in T cell subsets without obvious changes in expression of TCR, we analysed the TCR repertoire of cytotoxic T lymphocytes in Crohn's disease peripheral blood. Furthermore, we examined the effect of bacterial superantigens, staphylococcal enterotoxin B (SEB) and E (SEE) on the cytotoxic function of T cell subsets bearing different TCR V genes using MoAbs specific for CD3 and TCR V gene products in a redirected cytotoxicity assay. There was no difference between patients and controls in the cytotoxicity measured in concanavalin A (Con A)-stimulated peripheral blood mononuclear cells (PBMC) with anti-CD3 or with six of seven anti-TCR V gene MoAbs. However, the cytotoxicity of V beta 8 T cells was decreased in Crohn's disease patients. This was not due to a decrease in total or CD8+ T cells expressing V beta 8. Furthermore, in normal subjects, PBMC stimulation with SEE and SEB selectively expanded and increased the cytotoxicity of V beta 8 and V beta 12 T cells, respectively. In Crohn's disease, although SEB stimulation increased the number and cytolytic function of the V beta 12 subset, SEE stimulation failed to increase cytolytic activity of V beta 8+ T cells in spite of the expansion of V beta 8+ T cells. These results suggest that the changes in cytotoxic function observed in V beta 8 T cells in Crohn's patients may reflect previous exposure to a V beta 8-selective superantigen.

Crohn Disease↗
PubMed1995

Rehabilitation of the geriatric orthopaedic patient.

Older patients who are referred for rehabilitation after undergoing orthopaedic procedures have numerous age-related conditions that may interfere with physical performance and safety. The general rehabilitation goals are to return each patient to the premorbid functional level of mobility and self-care, teach the exercises that are to be performed after hospital discharge, reduce the risk of falls, and ensure that the patient is discharged to a safe environment. Before elective surgery, the elderly orthopaedic patient should be instructed to perform breathing exercises to prevent pulmonary complications and active lower limb exercises to maintain good circulation and joint mobility, and be instructed in functional activities for mobilization in and out of bed. Postoperatively, the interdisciplinary rehabilitation team must facilitate early resumption of active exercises and self-care tasks and discourage prolonged bed rest and dependency on nursing staff and family members. Physical and occupational therapy should be provided to restore mobility and self-care functions. If discharge to home is planned, the home environment should be assessed and modifications recommended to reduce the risk of falls and ensure independent functioning to the extent possible. When the rehabilitation goals have been obtained, the patient should be discharged from the hospital, but additional therapy may be required, either at home or at an outpatient facility.

Accidental Falls↗
PubMed1994

The role of interferon in the treatment of viral hepatitis.

Chronic viral hepatitis, frequently an asymptomatic disease, can persist for decades. Despite the lack of symptoms, prolonged infection can lead to the complications of cirrhosis, liver failure and hepatocellular carcinoma. The goal of therapy is to reduce the risk of developing these complications and to eradicate the infectious pool. Patients with ongoing viral replication appear to be at greatest risk for developing complications. These patients have been targeted for treatment. Numerous randomized studies of interferon treatment of chronic hepatitis B and C have been published in the last 8 years. The experience from these studies and more recent developments will be reviewed.

Hepatitis B↗
PubMed1994

The accessory bile duct of Luschka and bile leakage in laparoscopic cholecystectomy.

Postoperative bile leakage has been reported to occur in 0.2% to 1.5% of patients undergoing laparoscopic cholecystectomy. One of the not-so-common causes is the unrecognized accessory cystic duct of Luschka. We have prepared a case report of bile leakage due to unrecognized accessory bile duct during a laparoscopic cholecystectomy and a recommended technique for recognition and prevention.

Bile Ducts↗
PubMed1993

Effect of alpha-interferon treatment in patients with hepatitis B e antigen-positive chronic hepatitis B. A meta-analysis.

PURPOSE: To determine whether alpha-interferon is effective in terminating viral replication and in eradicating the carrier state in patients with chronic hepatitis B virus (HBV) infection. DATA SOURCES: Randomized controlled studies published in the English literature between January 1966 and June 1992 were identified through a MEDLINE computer search. STUDY SELECTION: Fifteen randomized controlled studies with a total of 837 adult chronic HBV carriers who were positive for hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) were identified. Studies were included if patients were treated for at least 3 months and followed for at least 6 months after cessation of therapy. RESULTS: Overall, the loss of HBsAg occurred 6% more often in interferon-treated patients than the natural seroconversion seen in controls (7.8% compared with 1.8%, P = 0.001), and the loss of viral replication occurred approximately 20% more often in treated patients than in controls (33% compared with 12% for loss of HBeAg and 37% compared with 17% for the loss of HBV DNA, P = 0.0001) if patients received interferon for 3 to 6 months and were followed for 6 to 12 months. Interferon also had a significant treatment effect on the development of antibodies to HBsAg (anti-HBs), antibodies to HBeAg (anti-HBe), and on the normalization of alanine aminotransferase levels. CONCLUSIONS: Alpha-interferon is effective in terminating viral replication and in eradicating the carrier state in patients with chronic HBV infection who are HBeAg positive when these patients are treated for 3 to 6 months and followed for 6 to 12 months after cessation of therapy. Follow-up studies are required to determine whether interferon reduces the risk for developing cirrhosis or hepatocellular carcinoma.

Adolescent↗
PubMed1992

Microprocessor-based near real-time bedside blood chemistry monitor.

A microprocessor-based instrument which integrates the function of a volumetric infusion pump with a blood chemistry analyzer has been developed. Presently, the instrument is capable of measuring Na+, K+, Ca++ and pH within approximately 40 sec at a frequency of up to every 2 min. The system is set up as an intravenous (IV) infusion pump with the addition of an array of disposable sensors placed at the distal end of the IV set. An isotonic IV solution is used to keep the site patent while also serving as a calibrant for the sensors. The instrument first calibrates the sensors, then withdraws approximately 0.6 ml of blood to come in contact with the sensors. Within approximately 15 sec, it displays the results, flushes the blood back into the patient and resumes normal infusion. There is no blood loss to the patient and no need to handle blood. The system was first validated with known aqueous controls and then used on-line in a variety of animal studies where dynamic fluctuation of electrolytes and pH occurred. Excellent correlation was found with off-line samples tested on conventional STAT analyzers. Some preliminary patient data is also presented.

Animals↗
PubMed1991

Chronic pancreatitis progressing to duodenal obstruction in the absence of classic symptoms.

We report the case of a 34-year-old alcoholic who was initially seen in March 1985 because of acute pancreatitis. A mass was demonstrated in the head of the pancreas. Serial sonogram and computed tomography scans over 4 1/2 years revealed progressive encroachment of the duodenum without symptoms attributable to obstruction. In 1989, three separate endoscopies with multiple biopsies showed chronic inflammation and strictures. Hypotonic duodenography confirmed stricture and obstructed duodenum. Surgical intervention is being considered. Duodenal obstruction secondary to chronic pancreatitis is rare. It may proceed subclinically for several years independent of continued alcohol use. Only when obstruction became severe in our patient did the classic symptoms of postprandial nausea, emesis, and weight loss become manifest. Obstructive jaundice from chronic pancreatitis due to stricture in the pancreatic portion of the common bile duct is uncommon.

Adult↗
PubMed1980

Serum antibodies to human fetal antigens in patients with systemic lupus erythematosus (SLE).

Serum antibodies to human fetal antigens were measured by a radiolabeled anti-immunoglobulin binding assay by using human fetal fibroblasts (Flow cell line No. 1000) as target cells. High titers of IgG antibody to the fetal cells were found in sera of patients with systemic lupus erythematosus (SLE). The antibody reacted with surface membrane antigens shared by various fetal tissues of human and murine origin but not by adult tissues. The reaction of the SLE antibody to the fetal cells was inhibited by heterologous antiserum to the Flow 1000 cells and antiserum to murine embryonic fibroblasts, but not by antiserum to human alpha-fetoprotein or human fibronectin. Absorption of SLE serum with isolated nuclei did not abolish the reaction indicating that these were not anti-nuclear antibodies. The antibody activity was found to reside in the F(ab')2 fragment. The serum titer of the anti-fetal antibody was higher in SLE patients with active disease than those in clinical remission.

Animals↗
PubMed1976

Glucosamine resistance in yeast. I. A preliminary genetic analysis.

Mutants of the yeast Saccaromyces cerevisiae which can grow on glycerol medium in the presence of 0.05% D (+) glucosamine have been isolated. Genetic analysis of 13 of these glucosamine resistant (GR) mutants demonstrated two modes of inheritance. One group of mutants (GR 5, 6, 7, 8, 9 and 10) gave results characteristic of non-Mendelian inheritance and it is suggested that these mutants represent one or more new mitochondial loci. Four of the remaining mutants showed clear-cut Mendelian inheritance. These mutants fell into two complementation groups and subsequent mapping experiments demonstrated that two independent loci, gay 1 and gay 2, unlinked to each other or to the centromeres of chromosomes I, II, IV, VIII or IX, were responsible for conferring glucosamine resistance in these mutants.

Chromosome Mapping↗
PubMedDate not supplied

Penicillium marneffei in bronchoalveolar lavage fluid.

Penicillium marneffei is a rare human pathogen that may infect either healthy or immunocompromised hosts. In methenamine silver-stained preparations of bronchoalveolar lavage fluid from a patient with dermatomyositis on steroid treatment, round-to-oval intracellular and extracellular microorganisms were found. The finding of occasional septate and elongated forms established the microorganism as probably P marneffei, which was confirmed on culture. Distinguishing this rare fungus from Pneumocystis carinii is important because these two diseases require different forms of treatment.

Bronchoalveolar Lavage Fluid↗