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Biomedical subjects

H Wei

Publications and source records attributed to H Wei.

At least 235 records · Page 13Linked to original sources
PubMed1989

Hepatocellular membrane function during chronic burn injury.

Hepatocellular membrane dysfunction, as indicated by depolarization of the membrane potential, occurs after acute injury and early bacteremia. To determine whether hepatocellular membrane dysfunction occurs in the setting of ongoing thermal injury and infection, Wistar rats were divided into four groups: (1) sham-burned, freely fed controls (FF); (2) rats sustaining approximately 30% total body surface area dorsal full-thickness scald burn (Burn); (3) rats sustaining burns as in group 2 followed by immediate inoculation of 1 x 10(8) CFU Pseudomonas aeruginosa (Burn/Inf); and (4) sham-burned rats pair-fed to the food intake of the Burn/Inf group (PF). On the third and seventh days postburn, body and liver weights were determined. In vivo hepatocellular transmembrane potentials were measured and hepatic ATP, RNA, DNA, and protein contents were assayed. By Day 7, despite greater weight loss in the Burn/Inf group than due to starvation alone (P less than 0.01 Burn/Inf vs FF and PF), hepatic mass was conserved. This was associated with hyperpolarization of the hepatic transmembrane potential (-46.6 +/- 1.5 vs -32.1 +/- 0.6 mV, Burn/Inf vs FF, P less than 0.01) and increases in RNA (141 +/- 9 vs 91 +/- 4 mg/liver, Burn/Inf vs FF, P less than 0.01) and DNA (37 +/- 5 vs 22 +/- 2 mg/liver, Burn/Inf vs FF, P less than 0.05) contents, with no change in ATP or hepatic protein contents. There was a significant hypercorticosteronemia observed in the Burn/Inf group (43 +/- 9 vs 2.8 +/- 0.7 micrograms/dl, Burn/Inf vs FF, P less than 0.01). This hepatic membrane hyperpolarization and augmented RNA content were not secondary to burn or starvation alone as the response in these groups was significantly less than that of the Burn/Inf group. It is suggested that this hepatic membrane hyperpolarization is one mechanism by which hepatic function is maintained during ongoing burn infection in the rat.

Adenosine Triphosphate↗
PubMed1989

Cachectin/tumor necrosis factor-alpha alters red blood cell kinetics and induces anemia in vivo.

Chronic inflammatory diseases are often associated with decreased red blood cell (RBC) mass. The cytokines cachectin/tumor necrosis factor-alpha (TNF) and interleukin 1 (IL 1) are produced by monocytes/macrophages in response to many inflammatory stimuli and have been implicated in the anemia of chronic disease. This study was undertaken to evaluate the mechanisms by which cachectin/TNF, IL 1, or endotoxin induce anemia. Hematologic parameters and RBC kinetics were quantitated in rats given chronic sublethal quantities of either recombinant human cachectin/TNF, recombinant human IL 1 alpha, or Salmonella endotoxin for 7 days. Cachectin/TNF or endotoxin treatment resulted in a 25 or 31% decrease, respectively, in total RBC mass, whereas RBC mass was unchanged by IL 1 administration. Anemia associated with either chronic cachectin or endotoxin administration was characterized by normal mean corpuscular volume, mean corpuscular hemoglobin content, and reticulocyte numbers. [59Fe]RBC survival was significantly shortened in animals given cachectin, IL 1 or endotoxin, but the magnitude of the response was greatest in cachectin/TNF-or endotoxin-treated rats. Although cachectin/TNF-IL 1-, or endotoxin treatment resulted in similar hypoferremia and shortened plasma iron half-life, endotoxin or cachectin/TNF treatment (but not IL 1) significantly reduced the incorporation of plasma 59Fe into newly synthesized RBCs. We conclude that chronic cachectin/TNF administration produces anemia by decreasing RBC synthesis and reducing the life span of circulating RBCs. An endogenous cachectin/TNF response during inflammatory disease may contribute to an associated anemic state, whereas the modestly reduced red cell life span induced by IL 1 does not lead to a net reduction in RBC mass, presumably owing to a preserved RBC synthetic rate.

Anemia↗
PubMed1989

Anticachectin/tumor necrosis factor-alpha antibodies attenuate development of cachexia in tumor models.

C57BL/6 mice bearing either a transplantable methylcholanthrene-induced sarcoma or Lewis lung adenocarcinoma were passively immunized every other day with a rabbit immunoglobulin fraction raised against murine cachectin/tumor necrosis factor-alpha. Mice bearing methylcholanthrene-induced sarcoma developed tumor-associated hypophagia that was attenuated by anticachectin immunoglobulin treatment. In the same tumor-bearing animals, anticachectin treatment also significantly reduced the extent of carcass protein and fat loss, and reduced tumor weight. Mice bearing Lewis lung adenocarcinoma did not develop significant anorexia or carcass lean tissue depletion as tumor growth progressed, but they lost carcass lipid. Treatment of Lewis lung adenocarcinoma bearing mice with anticachectin antibodies diminished the degree of carcass lipid depletion and prevented plasma hypertriglyceridemia. However, in both tumor models, anticachectin treatment did not affect either the development of anemia, hypoalbuminemia or the increase in serum amyloid P concentrations seen with increasing tumor burden. We conclude that an endogenous cachectin response, inhibitable by exogenously administered antibody, contributes to anorexia and to changes in body fat and protein metabolism in these tumor-bearing animals. Neutralizing endogenous cachectin production with antibodies offers the potential to reduce tissue wasting that is frequently associated with neoplastic disease, but it does not appear to affect all of the hematologic and acute phase responses in these murine tumor models.

Adenocarcinoma↗
PubMed1989

Cachectin/TNF or IL-1 alpha induces cachexia with redistribution of body proteins.

Macrophage secretory products are suspected to participate in the severe lean tissue wasting related to chronic illness. The protein metabolic effects of chronic, 7-day cachectin/tumor necrosis factor (cachectin) or interleukin 1 alpha (IL-1 alpha) administration in vivo were studied in male Wistar rats that were 1) freely fed, 2) pair fed, 3) total protein and calorie starved, 4) twice daily lipopolysaccharide (LPS) administered, 5) twice daily cachectin administered, and 6) twice daily IL-1 alpha administered. LPS, cachectin, or IL-1 alpha administration produced anorexia; weight loss in these groups was comparable to respective pair-fed animals. However, LPS, cachectin, or IL-1 alpha accelerated peripheral protein wasting while preserving liver protein content, unlike the pattern in the pair-fed or starved animals in which loss of liver proteins and relative preservation of skeletal muscle protein were observed. The decrease in skeletal muscle protein content in LPS- or cytokine-treated animals was associated with coordinate decreases in muscle mRNA levels for the myofibrillar proteins myosin heavy chain, myosin light chain, actin, and in the 18S and 28S subunits of ribosomal RNA. We conclude that chronic exposure to the cytokines, IL-1 alpha or cachectin, can simulate those body and muscle protein changes seen in experimental LPS administration or chronic disease and markedly differ from the pattern of protein redistribution due to caloric restriction.

Animals↗
PubMed1989

Immunosuppressive principles of Rehmannia glutinosa var. hueichingensis.

Separation of the immunosuppressive principles from Rehmanniae radix was done by monitoring hemolytic plaque-forming cells (HPFC) inhibitory activity to give two new phenethyl alcohol glycosides: jionosides A1 (4) and B1 (5), along with six known compounds: acetoside, isoacteoside, purpureaside C, echinacoside, and cistanosides A and F.

Animals↗
PubMed1988

Cachectin/tumor necrosis factor induces cachexia, anemia, and inflammation.

Cachexia is a potentially lethal syndrome of unknown etiology characterized by anorexia, weight loss, and protein wasting that frequently complicates the treatment of chronic inflammation and cancer. Cachectin/TNF was isolated during the search for a humoral mediator of cachexia and found to stimulate the breakdown of energy stores from adipocytes and myocytes in vitro, but the chronic effects of the monokine in vivo are not known. Sublethal doses of recombinant human cachectin administered twice daily for 7-10 d caused cachexia in rats, as evidenced by reduced food intake, weight loss, and depletion of whole-body lipid and protein stores. Significant anemia is also observed and found to be the result of decreased red blood cell mass, not expanded plasma volume. Leukocytosis and histopathological evidence of tissue injury and inflammation are observed in several organs, including omentum, liver, spleen, and heart. These data suggests that the exposure of the normal host to cachectin is capable of inducing a pathophysiological syndrome of cachexia, anemia, and inflammation similar to that observed during inflammatory states or malignancy.

Anemia↗
PubMed1988

Cachectin/TNF production in experimental burns and Pseudomonas infection.

Burn injury and infection result in significant losses of lean tissue. The cytokine cachectin/tumor necrosis factor has been implicated in this process but is not uniformly detected during infection. We sought to determine the relationship between body composition changes and in vivo hepatic levels of pretranslational message for cachectin (messenger RNA) in a burn and infection rodent model. Adult Wistar rats were grouped as follows: (1) freely fed, (2) 30% burn, (3) 30% burn with Pseudomonas aeruginosa infection, (4) pair fed, and (5) 30% burn and infection with recombinant cachectin. Compared with controls or animals only burned, burned and infected rats had a 100% increase in hepatic cachectin messenger RNA content, lost carcass protein, and exhibited muscle loss with sparing of liver mass. Tissue production of cachectin as well as other cytokines may be sufficient to mediate several body composition changes observed in response to injury and infection.

Animals↗
PubMed1987

Cachectin/tumor necrosis factor induces lethal shock and stress hormone responses in the dog.

Cachectin/tumor necrosis factor has been implicated as a mediator of lethal endotoxemia, but the metabolic and hemodynamic responses to this macrophage-derived peptide have been incompletely characterized. Cachectin was administered by intra-arterial infusion in two groups of beagle dogs at lethal (100 micrograms per kilogram) and sublethal (10 micrograms per kilogram) doses. The infusion produced serum cachectin levels (1 to 50 nanomoles per liter) similar to those achieved after experimental endotoxemia. The lethal response to cachectin was characterized by progressive hypotension, shock and death within three hours. Histopathologic findings included acute inflammation of the pulmonary interstitium, intravascular thrombosis with hemorrhagic necrosis, adrenal medullary necrosis and acute renal tubular necrosis. Cachectin infusion precipitated significant increases of plasma catecholamines, cortisol and glucagon in a dose response manner. Cachectin infused directly into the isolated hindlimb mediated reductions of skeletal muscle resting transmembrane potential and stimulated lactate efflux. Cachectin appears to occupy a crucial role in physiopathologic responses to infection, and likely participates in the mobilization of host energy stores, intravascular depletion and shock after lethal endotoxemia.

Animals↗
PubMed1979

The natural history of rheumatic fever and rheumatic heart disease in the Orient.

Studies published in the past 10 years suggest that group A streptococcal infections are frequent in the Orient and lead to a high incidence of rheumatic fever (RF) and rheumatic heart disease (RHD). In the present study, streptococcal infections were found to be more prevalent in Japan and Taiwan, whereas RF and RHD were more common and severe in the Philippines, Thailand, and Indonesia, particularly among the socioeconomically less privileged populations. The pattern of childhood RF varied: Carditis was the most common manifestation, occurring in 57% to 94% of the patients; polyarthritis was generally atypical and less common in the tropics; chorea minor and erythema marginatum were much more common in Japan, less common in Taiwan and rare in the tropics. RF recurrences were quite common and led to the development of new carditis, and deterioration or persistence of the pre-existing heart disease. The 5 year mortality rates differed greatly, ranging from zero to 42%. There was disappearance of the heart murmur in 16.5% to 37.5% of patients. Such apparent recovery was related to adherence to chemoprophylaxis. The major risk factors adversely affecting survival were the severity of carditis, inadequacy of medical service, non-compliance to chemoprophylaxis, RF recurrence, poor socioeconomic status, and high prevalence of group A streptococci. It is concluded that there is no uniform "Oriental-type" of natural history of RF and RHD. The natural history varies greatly among countries as is true in other parts of the world.

Adolescent↗
PubMed1976

Some problems in long-term prevention of streptococcal infection among children with rheumatic heart disease in Taiwan.

In Taiwan, rheumatic fever (RF) and rheumatic heart disease (RHD) remain widespread and constituting a health problem. The long-term prevention of streptococcal infections among rheumatic children has also failed to prevail, and yet has seldom been emphasized. Therefore, recurrence of RF remained prevalent. For an appraisal of the difficulties in the administration of long-term medication prophylaxis, a prospective study was started in 1967. One hundred and five consecutive cases of RF and RHD were followed up for more than 1 year to 6 years with an average of 4.4 years. One hundred and two cases received monthly injections of benzathine penicillin G for 6 months to 6 years, of whom 10 were switched to daily sulfa drugs; 1 case had oral penicillin daily for 6 years; in 12 cases, sulfa drugs were given for 6 months to 5 years. Fifty-one cases (48.6 %) stayed well in the program; 22 (21.0 %) stayed but were not compliant; 32 (30.4 %) dropped out soon or after staying in for more than 1 year. Major risk factors leading to non-compliance are; 1) apparent recovery from the illness or resumption of the normal activity; 2) cram session at school; 3) lack of easy medical care system; and 4) shortage of active participation by the health workers and general practitioners. The present study confirmed that the long-term prevention of streptococcal infection was effective and contributed to the decline of RF recurrence rate from more than 30 % down to 6%. Our study implicates that this important preventive program can not be achieved just only by the hospital staff, but should be approached jointly by all doctors, health and social workers, school teachers and the parents.

Birth Order↗
PubMed1976

Outcomes of children with rheumatic fever not diagnosed by revised (1965) Jones criteria.

The Jones criteria proposed in 1944 for the diagnosis of rheumatic fever (RF) underwent a modification in 1955, and then a revision in 1965. The importance of establishing antecedent streptococcal infection was stressed, and the criteria became more difficult to meet with. Thirty-two children, whose clinical and laboratory manifestations met the modified but not the revised Jones criteria were encountered at the National Taiwan University Hospital during 1967-1971. They were labeled as probable RF, and were treated and follwed for 1 month to 6 years (average 3.7 years). The diagnosis in each case was evaluated in the light of their outcomes. The diagnosis of RF was justified in 27 cases based upon the following observation: Favorable responses to anti-rheumatic treatment (27 cases); normalization of the enlarged heart with disappearance of the murmurs (3 cases); normalization of the enlarged heart with persistence of the murmurs (5 cases); significant reduction of the enlarged heart (12 cases); typical RF recurrence (8 cases); development of pure mitral stenosis (1 case); valvular pathology verified at surgery or autopsy (4 cases). The diagnosis in the rest of 5 cases remained not confirmed or negated because that: the enlarged heart stayed unchanged (1 case); the child remained uneventful and free of cardiac involvement (2 cases); and the patient died and no postmortem study obtained (2 cases). The risk factors leading to underdiagnosis in these patients are: 1) late coming under observation; 2) no response in ASO titers; 3) limited studies for the evidence of streptococcal infection; and 4) drug induced modification of the clinical manifestations. This study implicates that patients who are very suspicious of RF on the clinical grounds, yet fail to meet the revised Jones criteria, especially those with established valvular heart disease, should be labeled as cases of probable RF, and be treated, followed, and placed on prolonged chemoprophylaxis until proved otherwise. Recurrence of RF may thus by prevented, and the regression or even natural healing of the rheumatic heart disease will become a possibility.

Adolescent↗