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Biomedical subjects

W Henry

Publications and source records attributed to W Henry.

At least 19 recordsLinked to original sources
PubMed1992

Increased serum apolipoprotein(a) in patients with chronic renal failure treated with continuous ambulatory peritoneal dialysis.

Patients with end-stage renal failure (ESRF) on renal replacement therapy are at significantly increased risk of cardiovascular disease. To determine whether altered concentrations of apolipoprotein(a) (apo(a)), the plasminogen-like protein moiety of the atherogenic particle lipoprotein(a), contributed to this increased risk, apo(a) concentrations were measured in 48 non-diabetic patients with ESRF treated by continuous ambulatory peritoneal dialysis (CAPD) therapy and compared with 65 controls. Apo(a) concentration was increased in CAPD patients compared to controls (geometric mean 419 units/l versus 137 units/l; ratio of means 3.06 (95% CI 1.95-4.80). We conclude that CAPD patients have increased apo(a) concentrations which may contribute to their increased risk of cardiovascular disease.

Adult↗
PubMed1991

Hemodynamic effects of endothelin-1 in the newborn piglet: influence on pulmonary and systemic vascular resistance.

The aim of this study was to investigate the influence of endothelin-1 (ET-1) on the pulmonary and systemic circulations in newborn piglets. Twelve piglets (mean age of 6.8 days, range of 1-12 days) were anesthetized with chloralose-urethane and ventilated at FiO2 = 1.0. Animals were instrumented to measure cardiac output (CO), pulmonary artery pressure (PAP), aortic pressure (AoP), left atrial pressure (LAP), and right atrial pressure (RAP). Six piglets received a control saline injection into the pulmonary artery (PA), and six piglets received one injection of ET-1 (500 ng/kg) into the PA while PAP, AoP, LAP, RAP, CO, and heart rate (HR) were measured simultaneously at 20-s intervals with pulmonary vascular resistance (PVR) and systemic vascular resistance (SVR) calculated by computer. Administration of ET-1 into the PA led to (a) a transient decrease in mean PAP (delta max of -4 +/- 2 mm Hg, p less than 0.001); (b) a biphasic response (an initial decline followed by a substantial increase) in PVR (delta max of -760 +/- 460 dyn cm/s5, p less than 0.01, and delta max of +1,490 +/- 1,360 dyn cm/s5, p less than 0.05) and in AoP (delta max of -12 +/- 7 mm Hg, p less than 0.005, and delta max of +11 +/- 6 mm Hg, p less than 0.005); (c) an increase in SVR (delta max of +5,930 +/- 2,330 dyn cm/s5, p less than 0.05); and (d) an initial increase in CO (delta max of +0.06 +/- 0.03 L/min, p less than 0.05) followed by a decrease (delta max of -0.09 +/- 0.05 L/min, p less than 0.05). These responses have not been observed in adult species and may indicate a developmental difference in the response of the pulmonary circulation to ET-1 administration.

Animals↗
PubMed1989

Laser-assisted thermal angioplasty in human peripheral artery occlusions: mechanism of recanalization.

Recanalization of completely occluded superficial femoral or popliteal arteries was attempted in 18 patients with use of an Argon laser-mediated thermal probe. The length of the occluded segments varied between 0.5 and 26.0 cm, but 67% of the occlusions were greater than 9 cm long. The initial success rate was 67%. Arterial perforation occurred in six patients but was not associated with major complications. To study the mechanism of the laser-mediated thermal probe, thermal recanalization was performed on 11 human arterial segments in vitro obtained after amputation, and mechanical recanalization was performed in vitro in 10 human peripheral arteries with use of a guide wire and catheter technique. An additional four arteries were studied with the laser probe as a non-heated mechanical device. Both the mechanical and thermal devices appear to follow a similar pathway through a complete obstruction. These studies suggest that the thermal probe burns through soft fibrous tissue but is mechanically deflected away from hard fibrocalcific plaque. The probe then advances along the plane between the intimal plaque and the media for a variable length before perforating through the adventitia. These observations suggest that the major mechanism of thermal probe recanalization may be a mechanical process. It appears that thermal probe devices do not inherently seek the true lumen of an occluded artery and that better guidance systems need to be developed.

Aged↗
PubMed1988

Isoniazid preventive therapy for tuberculosis. Are we losing our enthusiasm?

Contact investigation activities of the Tennessee Department of Health and Environment (TDHE) Tuberculosis (TB) Control Program from 1979 to 1985 were reviewed. Out of 32,722 identified contacts, 6,030 (20.1 percent) were infected (positive purified protein derivative [PPD]). Only 2,731 (45 percent) of the infected contacts were started on preventive therapy. Both the absolute number and the relative percentage of infected contacts starting on INH prevention therapy have gradually declined over the years. While 569 (67 percent) of the infected contacts were started on preventive treatment in 1979, only 296 (37.5 percent) received isoniazid (INH) preventive therapy in 1985. Although an increasing percentage of those starting preventive therapy completed the prescribed course, the enthusiasm for recommending preventive therapy has declined for the infected individuals above the age of 15. More enthusiasm and efforts are needed from physicians in initiating and maintaining INH preventive therapy to accomplish tuberculosis eradication.

Adolescent↗
PubMed1987

Glutamine metabolism in rat skeletal muscle wounded with lambda-carrageenan.

Wounding with lambda-carrageenan results in a marked decrease in the intracellular-free glutamine content of rat skeletal muscle. The potential mechanisms for this finding, including alterations in glutamine release, glutamine utilization, and glutamine synthesis, were investigated in rats under pentobarbital anesthesia. Wounding did not increase glutamine release from muscle during incubation or isolated hindlimb perfusion. Wounded muscle utilized more glutamine than nonwounded muscle, as measured both by the production of [14C]O2 and of -glutamate from labeled glutamine. Maximal glutamine synthetase activity was increased by wounding. The increase in glutamine synthetase activity in wounded muscle was prevented by adrenalectomy and restored by replacement doses of corticosterone in wounded adrenalectomized animals. The decrease in muscle free glutamine induced by wounding is therefore not mediated by an increase in the release of this amino acid, nor by a reduction in the tissue capacity for glutamine synthesis, but by an increase in glutamine utilization at the site of injury. This difference is apparently determined by the utilization of glutamine by the cellular components of the inflammatory infiltrate, which were shown to be capable of active glutaminolysis.

Adrenalectomy↗
PubMed1986

The relationship of purine metabolism to the macrophage-mediated increase of high energy phosphates in skeletal muscle.

Previous investigations have demonstrated that the high energy phosphate and adenine nucleotide content of wounded tissue are decreased. Purine metabolism was investigated in incubated lambda-carrageenan wounded skeletal muscle and in muscle exposed to peritoneal macrophages or macrophage-conditioned media. Wounded muscle released predominately uric acid into the incubation medium; whereas, nonwounded muscle released inosine, hypoxanthine, and xanthine as well as uric acid. Macrophages incubated with nonwounded muscle changed the purine release pattern toward one of wounded muscle. The conversion of inosine to allantoin and uric acid by macrophages increased linearly with the addition of up to 1 X 10(7) macrophages per incubation. Muscles incubated in macrophage-conditioned media had a decreased release of inosine and hypoxanthine and higher tissue levels of creatine phosphate, ATP, ADP, AMP, and adenosine compared to muscles incubated in standard media. These data suggest that the macrophage determines the pattern of purine release from wounded skeletal muscle in the incubated system and that in conditioned media a high energy phosphate promoting factor may exert its effect by mechanisms that augment the adenine purine pool.

Adenine Nucleotides↗
PubMed1985

Digital coronary roadmapping as an aid for performing coronary angioplasty.

In an attempt to improve visualization of the position of the guidewire and dilatation balloon during coronary angioplasty, a method was developed called digital coronary roadmapping. With this method a digitally acquired coronary angiogram is interlaced with the live fluoroscopic image of the guidewire and balloon catheter. The digital coronary angiogram is superimposed at the same magnification and radiologic projection as the live fluoroscopic image onto the video monitor above the catheterization table. The digital roadmap image thus provides immediate feedback to the angiographer to assist in directing the guidewire into the appropriate coronary artery branch and to help in placement of the balloon so that it straddles the site of stenosis.

Adult↗
PubMed1985

A macrophage-mediated factor that increases the high energy phosphate content of skeletal muscle.

A marked cellular infiltrate accompanies wounding. The phagocytic and bacteriocidal activities of this infiltrate require increased substrate and O2 consumption. This rapid utilization of available oxygen and substrates could jeopardize an already compromised resident cellular component of a wound. Recent studies have demonstrated macrophage-mediated cell stimulatory agents which induce proliferation of nonlymphoid mesenchymal cells. This study was designed to examine macrophage-resident tissue interactions and their possible significance in wounded tissue. A reconstituted wound system was designed which combines the major components of a lambda-carrageenan skeletal muscle wound (muscle + macrophages). The extensor digitorum longi (EDL) of male Fisher rats were incubated in a standardized fashion. The groups of EDL were muscle incubated alone, muscle with the addition to the incubate of activated peritoneal macrophages or muscle with the addition of a conditioned supernatant from the incubation of activated or nonactivated peritoneal macrophages. Muscle ATP and CP content were noted to be increased 46 and 22%, respectively, when macrophages and skeletal muscle were coincubated. Macrophage-conditioned media from activated or nonactivated macrophages increased the ATP and CP muscle content 44 and 37%, respectively. Preliminary characterization of this high energy phosphate (HEP) promoting factor demonstrates it to be heat and cold stable and less than 10,000 Da. Therefore, a macrophage-mediated transferable factor is capable of increasing the HEP content of skeletal muscle in an in vitro system. This may have important consequences in maintaining host cell integrity following injury.

Adenosine Triphosphate↗
PubMed1985

Macrophage interaction with skeletal muscle: a potential role of macrophages in determining the energy state of healing wounds.

A decrease in ATP and creatine phosphate (CP) is characteristic of local injury to skeletal muscle. Recent data have suggested adequate potential for high-energy phosphate production in the wounded tissue. Thus, an adequate explanation for the deficit in the high-energy tissue content in wounds was lacking. Since the wound has multiple components (muscle + cellular infiltrate), the tissue content represents the summation of these components. Therefore, a technique to separate these components was designed. Using a 0.5% solution of lambda-carrageenan as the wounding agent, the extensor digitorum longus muscles (EDL) of male Fisher rats were unilaterally wounded with intramuscular injections. Five days later, both wounded and contralateral nonwounded muscles were incubated in a standardized fashion. The groups of EDL were: wounded as described, contralateral nonwounded, or contralateral nonwounded with the addition to the incubate of 6 X 10(6)/ml lambda-carrageenan elicited peritoneal macrophages. Following incubation, the individual component parts of the system (muscle and macrophage) were rapidly frozen and assayed for high-energy phosphate and DNA content. Examination of the high-energy phosphate content of the separate components of a wound demonstrated that macrophages increased the ATP and CP content of normal skeletal muscle. Yet when total high-energy phosphate content was normalized for total DNA (muscle + macrophages) in the reconstituted system, the values approximated those of wounded muscle.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenosine Triphosphate↗
PubMed1984

Evidence for aerobic glycolysis in lambda-carrageenan-wounded skeletal muscle.

Classically, increased lactate production in wounded tissue is ascribed to anaerobic glycolysis although its oxygen consumption has been found to be similar to normal tissue. This apparent inconsistency was studied in a standardized isolated perfused wound model. Male Sprague-Dawley rats were wounded (group W) with intramuscular injections of lambda-carrageenan and fed ad lib.; not wounded and pair fed to the decreased food intake of the wounded animals (group PFC); or not wounded and fed ad lib. (group ALC). After 5 days, the hindlimbs of animals from each group were either perfused using a standard perfusate with added [U-14C]glucose or [1-14C]pyruvate or assayed for the tissue content of lactate and pyruvate. In addition, the effect of a 30% hemorrhage on the tissue lactate and pyruvate concentration was examined. Wounding increased glucose uptake and lactate production by 100 and 96%, respectively, above that seen in ALC animals. Oxygen consumption was unchanged by wounding (5.74, 5.14, and 5.83 mumole/min/100 g in W, PFC, and ALC, respectively). Glucose and pyruvate oxidation were also unaltered among the groups. Hemorrhage resulted in a comparable increase in lactate and pyruvate in tissue from wounded and pair-fed control animals (above those concentrations found in tissue harvested without preexisting hemorrhage). As a consequence, the same relationship in L/P ratio was maintained after hemorrhage. Taken together, these results confirm the presence of aerobic glycolysis in wounded tissue (unchanged oxygen consumption, glucose, and pyruvate oxidation). In addition, pyruvate dehydrogenase activity in the wound was apparently the same as that found in muscle from pair-fed control animals.

Aerobiosis↗
PubMed1981

Life-threatening complications of varicella.

We reviewed the records of 96 children hospitalized with varicella from July 1, 1975 to June 30, 1980. Eighty-one were immunologically normal and 15 were immunocompromised on the basis of neoplasia, immunosuppressive therapy, or genetic disease. These children experienced 106 complications including viral dissemination-encephalitis (44), bacterial infection (25), Reye's syndrome (17), unusual cutaneous lesions (eight), drug overdose (five), diabetic ketoacidosis (two), neonatal infection (two), dehydration (two), and exacerbation of preexisting nephrosis (one). The length of hospitalization varied from one to 38 days with a median of five days. There were ten varicella pneumonia (one), of neonatal varicella (one), and of a ruptured mycotic aneurysm secondary to septicemia (one). This review demonstrates (1) a substantial occurrence of life-threatening complications of varicella in childhood, and (2) a need for prospective epidemiologic data on the incidence of complications to determine the scope and extent of varicella vaccination.

Adolescent↗
PubMed1981

Cellulitis: initial management.

Although Staphylococcus aureus and Streptococcus pyogenes cause the majority of cellulitis, recent studies have shown a significant role for Hemophilus influenzae in facial, and less frequently, nonfacial infections. We devised an algorithm for the initial management of cellulitis based on our previous investigations showing a correlation of this organism with fever, leukocytosis, and facial involvement. Children were divided into four groups characterized as follows: Group I - extremity, temperature less than 38.5 C; Group II - extremity, temperature greater than 38.5 C, WBC less than 15,000/cu mm; Group III - extremity, temperature greater than 38.5 C, WBC greater than 15,000/cu mm; and Group IV - facial. Forty-five children were successfully followed. There were 34 in Group I, five in Group II, one in Group III, and five in Group IV. Two children in Group IV and the only child in Group III had H influenzae, recovered form the blood (3) or a direct aspirate (1). All three were febrile, with a range of 39.5 C to 40.1 C and has an elevated white blood cell count with a range of 19,200/cu mm to 26,000/cu mm. With one exception, children with cellulitis not due to H influenzae did not have both fever and leukocytosis. This algorithm allows the clinician to identify children with H influenzae cellulitis who are at risk for septic complications while minimizing unnecessary diagnostic or therapeutic interventions.

Adolescent↗
PubMed1980

Evaluation of cardiac function in patients with thalassemia major.

The application of noninvasive techniques to the evaluation of cardiac function in iron overload has identified a high incidence of abnormalities in asymptomatic patients prior to the onset of overt cardiac deterioration. Of the tests we have used, radionuclide cineangiography appears to be the most sensitive because it can be conveniently applied during the physiological stress of exercise. Other tests of cardiac function that include stress are also likely to be more sensitive than resting measurements of cardiac function. Systematic application of these techniques to the study of patients on iron chelation therapy should results in an early determination of the efficacy of such treatment.

Adolescent↗
PubMed1980

Hepatoma visualization with Tc-99m pyridoxylidene glutamate.

Tc-99m sulfur colloid is concentrated in Kupffer cells of the liver, whereas the new biliary agents are processed by hepatic parenchymal cells. A case of primary hepatocellular carcinoma, appearing as a defect on sulfur-colloid liver scan and visualized on a biliary scan, is presented. The possible role of biliary scanning in the evaluation of a defect on sulfur-colloid liver scan is discussed.

Aged↗
PubMed1976

In vitro studies on the use of penicillamine with tartar emetic against Schistosoma mansoni worms.

In vitro studies were carried out to test Sb125 tartar emetic (T.E.) in concentrations of 75, 100, 125, 150 and 200 mug/ml of rabbit serum and these concentrations together with penicillamine in ratios ranging from 1:1 to 1:6 for their effect on the motility and antimony uptake by Schistosoma mansoni worms. The motility was observed microscopically every half hour for six hours and the Sb125 content was measured by a scintillation counter at one hour intervals for five hours. Results indicate that the ratio in which penicillamine is used with T.E. is very important. The antimony uptake by the worm is reduced, and the onset of T.E. action is delayed when it is used with penicillamine in a ratio exceeding 1:2.

Animals↗