Mechanics of the anterior drawer and talar tilt tests. A cadaveric study of lateral ligament injuries of the ankle.

We analyzed the changes in lateral ligament forces during anterior drawer and talar tilt testing and examined ankle joint motion during testing, following an isolated lesion of the anterior talofibular ligament (ATFL) or a combined lesion of the ATFL and calcaneofibular ligament (CFL). 8 cadaver specimens were held in a specially designed testing apparatus in which the ankle position (dorsiflexion-plantarflexion and supination-pronation) could be varied in a controlled manner. Ligament forces were measured with buckle transducers, and joint motion was measured with an instrumented spatial linkage.

Lipopolysaccharide depresses cardiac contractility and beta-adrenergic contractile response by decreasing myofilament response to Ca2+ in cardiac myocytes.

Lipopolysaccharide (LPS) plays a key role in the pathogenesis of sepsis. Cardiac function and the inotropic response to beta-adrenergic stimulation are impaired in sepsis. We hypothesized that LPS, in clinically relevant levels (1 ng/mL), directly depresses contractility and beta-adrenergic responses in cardiac myocytes.

Endothelin-1 ameliorates contractile depression by lipopolysaccharide in cardiac myocytes.

Lipopolysaccharide (LPS) induces cardiac depression by activating nitric oxide pathways to increase guanosine 3',5'-cyclic monophosphate (cGMP), a second messenger of nitric oxide. Endothelin-1 (ET-1) may interact with nitric oxide pathways. We hypothesized that ET-1 modulates LPS-induced contractile depression in cardiac myocytes.

Biomechanics of ankle ligament reconstruction. An in vitro comparison of the Broström repair, Watson-Jones reconstruction, and a new anatomic reconstruction technique.

We wanted to use biomechanical testing in a cadaveric model to compare the Broström repair, the Watson-Jones reconstruction, and a new anatomic reconstruction method. Eight specimens were held in a specially designed testing apparatus in which the ankle position (dorsiflexion-plantar flexion and supination-pronation) could be varied in a controlled manner. Testing was done with intact ligaments and was repeated after sectioning of the anterior talofibular ligament and the calcaneofibular ligament and after a Broström repair, a Watson-Jones reconstruction, and a new anatomic reconstruction were performed.

Depyrogenation of digestive enzymes reduces lipopolysaccharide tolerance in isolated cardiac myocytes.

The isolated myocyte is useful for examining the direct cardiac effects of substances such as lipopolysaccharide (LPS) and cytokines. However, the digestive enzymes used for standard cell isolation procedures are contaminated by several hundred ng/ml LPS. We depyrogenated the digestive enzymes with a series of Triton X-114 and Polymyxin B washes to remove 99.

Lipopolysaccharide induces cell shrinkage in rabbit ventricular cardiac myocytes.

The effects of 10 ng/ml of lipopolysaccharide (LPS) on cell volume were examined in rabbit left ventricular myocytes. The myocytes were isolated with depyrogenated digestive enzymes (< 0.7 ng/ml of LPS) to minimize tolerance.

Influenza neuraminidase inhibitors possessing a novel hydrophobic interaction in the enzyme active site: design, synthesis, and structural analysis of carbocyclic sialic acid analogues with potent anti-influenza activity.

The design, synthesis, and in vitro evaluation of the novel carbocycles as transition-state-based inhibitors of influenza neuraminidase (NA) are described. The double bond position in the carbocyclic analogues plays an important role in NA inhibition as demonstrated by the antiviral activity of 8 (IC50 = 6.3 microM) vs 9 (IC50 > 200 microM).

Endotoxin-induced cardiac depression is associated with decreased cardiac dihydropyridine receptors in rabbits.

Endotoxin depresses left ventricular (LV) contractility independently of alterations in loading conditions, acidosis, or hypoxia (Hung and Lew, 1993a). We evaluated if endotoxin-induced LV depression is associated with a decrease in functional L-type calcium channels, as reflected by the number of dihydropyridine receptors measured by [3H]-PN200-110 binding. New Zealand white rabbits were instrumented with sonomicrometers to measure the end-systolic pressure-volume relationship after i.

Intraoperative force-setting did not improve the mechanical properties of an augmented bone-tendon-bone anterior cruciate ligament graft in a goat model.

It has been hypothesized that load affects the mechanical properties of an anterior cruciate ligament graft while it remodels. The goal of this study was to use an existing goat model to evaluate the effect of intraoperative set force on the postoperative mechanical properties of an autograft that had been augmented with a synthetic segment. The following questions were addressed.

Serum tumor necrosis factor-alpha does not mediate endotoxin-induced myocardial depression in rabbits.

Tumor necrosis factor-alpha (TNF-alpha) is an endogenous mediator for several effects of endotoxin. To evaluate whether TNF-alpha mediates endotoxin-induced left ventricular (LV) dysfunction, we measured LV function (sonomicrometers) and serum TNF-alpha (cytolytic assay) in anesthetized rabbits given endotoxin (100 micrograms/kg iv). In the control group (n = 8), systolic depression (defined by a > 10% increase in end-systolic volume at a matched end-systolic pressure) developed in four rabbits and diastolic dilation (> 10% increase in end-diastolic volume at a matched end-diastolic pressure) developed in three rabbits.

Incidence of pulmonary tuberculosis in Korean civil servants.

Setting: Longitudinal epidemiological study based on civil servants in Korea.

Objective: To estimate the incidence of pulmonary tuberculosis (PTB) for the general population from a reliable sample.

Design: New active PTB developing between 1988 and 1990 in civil servants has been determined from (1) the findings of biennial medical examinations and (2) perusal of the medical records of those claiming health insurance for tuberculosis (TB).

Incidence of pulmonary tuberculosis among diabetics.

Setting: Longitudinal epidemiological study based on diabetic and non-diabetic civil servants in Korea.

Objective: To determine a comparative incidence of pulmonary tuberculosis (PTB) between diabetic and non-diabetic subjects.

Design: Investigation of newly developed PTB among diabetics and non-diabetics between 1988 and 1990, on the basis of biennial medical examination and the medical records of those who claimed health insurance for tuberculosis.

Survey of knowledge, attitudes and practices for tuberculosis among general practitioners.

Setting: Representative sample survey of knowledge, attitudes and practices (KAP) for tuberculosis among private general practitioners (GPs) in 1993 in Korea,

Objective: To investigate the KAP of general practitioners on the prevention and treatment of tuberculosis.

Design: Questionnaire surveys were performed for 923 private general practitioners through 29 health centres.

Results: 49% of GPs considered that the Korean tuberculosis situation is not serious.

Sarcoplasmic reticulum in cardiac length-dependent activation in rabbits.

After a step increase in length of rabbit right ventricular papillary muscles, active stress increased immediately followed by a further slow increase in stress over 15-20 min. We studied the contribution of the sarcoplasmic reticulum (SR) to the slow change in stress (SCS) after changing muscle length from 85 to 95% of length at which active force development was maximal. SCS amounted to 32.

Endotoxin-induced left ventricular depression is blocked by nitrogen mustard or dimethylthiourea in rabbits.

We examined endotoxin-induced myocardial depression in 31 anesthetized rabbits using left ventricular end-systolic and end-diastolic pressure-volume relationships (sonomicrometers). In the control group, endotoxin (100 micrograms/kg iv) induced systolic depression (> 10% increase in end-systolic volume at matched end-systolic pressure) in 9 of 16 and diastolic dilation (> 10% increase in end-diastolic volume at matched end-diastolic pressure) in 8 of 16 rabbits within 7 h, unrelated to hypotension, acidosis, or hypoxia. Seven rabbits were pretreated with nitrogen mustard (1-2 mg/kg iv 4 and 2 days before) to decrease circulating neutrophils and monocytes by 98%.

Active force in rabbit ventricular myocytes.

Although recent technical advances have established the feasibility of force measurements in single cardiac myocytes, the physiological relevance of this model has not been fully evaluated. We measured active force and sarcomere length in single rabbit left ventricular myocytes and compared their physiological responses to changes in stimulus interval, calcium concentration and sarcomere length to results from isolated papillary muscles. Myocytes were attached to two poly-L-lysine-coated glass plates and force was measured with a capacitive force transducer (Cambridge 406A).

Opposing effects of ultraviolet B irradiation on interleukin-1 receptor antagonist and interleukin-1 alpha messenger RNA expression in a human epidermoid carcinoma cell line.

Interleukin-1 receptor antagonist (IL-1RA) is a cytokine that acts to antagonize IL-1 activity without agonist function. The expression of IL-1RA has been reported in many cell types, including the keratinocyte that covers the outer most part of the skin. However the modulation of IL-1RA by ultraviolet B (UVB), which is the most biologically active UV, has not been reported yet.

Asynchrony and ryanodine modulate load-dependent relaxation in the canine left ventricle.

Load-dependent relaxation was studied in six anesthetized dogs by inflating an intra-aortic balloon to increase peak left ventricular (LV) pressure by 1-20 mmHg within a single cardiac cycle. A series of timed and graded pressure loads was produced by inflating the balloon either during diastole (early loads) or midsystole (midsystolic pressure loads). The rate of LV pressure fall was measured with the time constant (tau).

Method for establishing and measuring in vivo forces in an anterior cruciate ligament composite graft: response to differing levels of load sharing in a goat model.

In order to determine the appropriate load history for optimal remodeling of an anterior cruciate ligament graft, methods for establishing and measuring the graft force due to an external load could be set to a preselected value in in vivo are required. Our objectives with this study were to (a) develop a method in which the graft force due to an external load could be set to a preselected value in a living animal, (b) show that this force could be maintained after fixation, and (c) determine what happens to the forces after the animal has functioned for as long as 2 weeks postoperatively, when differing levels of load sharing between the segments had been set at surgery. The anterior cruciate ligament was reconstructed in 12 goats with use of a bone-patellar tendon-bone graft and a synthetic augmentation device.

Cardiac myocyte function and left ventricular strains after brief ischemia and reperfusion in rabbits.

Background: After a brief episode of ischemia, myocardial function may be depressed for prolonged periods despite reperfusion. The mechanisms of postischemic dysfunction differ depending on the experimental model. Regional ischemia and reperfusion in the intact animal provide a clinically relevant model, but experimental variables are difficult to control.

Hepatic uptake of a bone scan agent (99mTc-MDP) in a patient with amyloidosis associated with plasma cell dyscrasia.

This case report describes diffuse hepatic uptake of a diphosphonate bone scan agent (Technetium-99m-MDP) in a patient with amyloidosis associated with a plasma cell dyscrasia. Amyloid infiltration is one of the more rare, but well recognized, causes of hepatic uptake of bone scan tracer. Other causes are also discussed in this case report.

Mechanisms of volume-induced increase in left ventricular contractility.

Volume-induced increases in left ventricular (LV) contractility were studied in 18 anesthetized dogs. Denervation eliminated cardiac reflexes, and hearts were paced at 100 +/- 9 (SD) beats/min. Acute volume loading increased LV end-diastolic pressure from approximately 4 to 14 mmHg within 1 min.

The sixth Nationwide Tuberculosis Prevalence Survey in Korea, 1990.

Setting: Nationwide random sample survey for tuberculosis in 1990.

Objective: To investigate the prevalence of tuberculosis infection, morbidity and drug resistance and BCG coverage, and to compare the findings with those of the previous 5 surveys.

Design: The following investigations were performed: tuberculin test, BCG scar screening, chest miniature radiography (70 mm x 70 mm) for those aged over 5 years, sputum direct smear, culture and drug susceptibility test, and a questionnaire to obtain history of chemotherapy and symptoms.

Temporal sequence of endotoxin-induced systolic and diastolic myocardial depression in rabbits.

Twelve anesthetized rabbits received endotoxin (175 +/- 38 micrograms/kg i.v., mean +/- SD) to evaluate the temporal sequence of alterations in left ventricular (LV) function.