Randomized study of chemoembolization as an adjuvant therapy for primary liver carcinoma after hepatectomy

From April 1990 to December 1993, 140 patients were recruited to a randomized study to evaluate transcatheter hepatic arterial chemoembolization (TACE) as an adjuvant therapy for primary liver carcinoma after hepatectomy. This study investigated the principle, techniques and results of TACE. The results showed that the intrahepatic recurrence rate was 48.9% in the patients who underwent radical resection only, but only 21.3% in the patients who also underwent TACE 3-4 weeks after hepatectomy (P < 0.01). The 1-, 2-, 3-, and 4-year survival rates were 72.3%, 52.7%, 35.1%, and 35.1% respectively for the patients who underwent radical resection only, and were 97.9%, 85.5%, 69.5%, and 56.9% for the patients who also underwent TACE 3-4 weeks after radical resection (P < 0.001). The 1-, 2-, 3-, and 4-year survival rates were 38.9%, 0%, 0%, and 0% for the patients who underwent palliative resection only, and were 68.3%, 32.3%, 21.5%, and 21.5% respectively for the patients undergoing TACE 3-4 weeks after palliative hepatectomy (P < 0.001).     

The rotator cuff-deficient arthritic shoulder: diagnosis and surgical management

The symptomatic rotator cuff-deficient, arthritic glenohumeral joint poses a complex problem for the orthopaedic surgeon. Surgical management can be facilitated by classifying the disorder in one of three diagnostic categories: (1) rotator cuff-tear arthropathy, (2) rheumatoid arthritic shoulder with cuff deficiency, or (3) degenerative arthritic (osteoarthritic) shoulder with cuff deficiency. If it is not possible to repair the cuff defect, surgical management may include prosthetic arthroplasty, with the recognition that only limited goals are attainable, particularly with respect to strength and active motion. Glenohumeral arthrodesis is a salvage procedure when other surgical measures have failed. Arthrodesis is also indicated in patients with deltoid muscle deficiency. Humeral hemiarthroplasty avoids the complications of glenoid loosening and is an attractive alternative to arthrodesis, resection arthroplasty, and total shoulder arthroplasty. The functionally intact coracoacromial arch should be preserved to reduce the risk of anterosuperior subluxation. Care should be taken not to "overstuff" the gleno-humeral joint with a prosthetic component. In cases of significant internal rotation contracture, subscapularis lengthening is necessary to restore anterior and posterior rotator cuff balance. If the less stringent criteria of Neer's "limited goals" rehabilitation are followed, approximately 80% to 90% of patients treated with humeral hemiarthroplasty can have satisfactory results.     

The increase in the cardiodepressant activity and vasopressin concentration in the sella turcica venous blood during vagal afferents stimulation or after angiotensin II infusion

It has previously been demonstrated that the cardiodepressant activity is present in the bovine hypothalamic extract and in the fluid incubating the posterior pituitary lobe "in situ". The present study was an attempt to reveal if the cardiodepressant factor and vasopressin were simultaneously released from the pituitary into blood. The samples of venous blood flowing from the sella turcica and, for comparison, from the posterior paw were collected in anaesthetized rats. Blood from the sella turcica was collected with a fine cannula inserted into the internal maxillary vein. The concentration of vasopressin in blood plasma was determined by radioimmunoassay and cardiodepressant activity--using a biological test on a spontaneously discharged pacemaker tissue of the right auricle of the right heart atrium. Stimulation of the central ends of the cut vagus nerves or intra-arterial infusion of angiotensin II simultaneously caused an increase in the cardiodepressant activity and vasopressin concentration in the sella turcica venous blood. The cardiodepressant activity and vasopressin concentration was also enhanced to some degree in blood outflowing from the posterior paw. Present results indicate that both vasopressin and the cardiodepressant factor are released into blood from the posterior pituitary lobe.     

Computational studies of 'whiplash' injuries

The term 'whiplash' was initially used to describe injuries to the neck caused by the head being forced backwards during a rear-end collision in cars without head restraints. The addition of head restraints in the 1970s was expected to solve this problem by preventing excessive extension of the neck but experience suggests the problem still exists. This paper reviews available experimental studies of whiplash and uses the data to construct a finite element model which is capable of dynamically simulating whiplash collisions and predicting the forces in all the relevant neck ligaments. For the first time, it is shown that trauma occurs long before the head hits the head restraint as a result of displacement between the head and the torso caused by the head's inertia leading to markedly different acceleration histories. It is concluded that experimental and computational studies must be used together to produce progress in biomechanical studies.     

Endothelin-1 does not contribute to ischemia/reperfusion-induced vasoconstriction in skeletal muscle

The experiment reported was designed to investigate whether endothelin-1 (ET-1) contributes to vasospasm and poor perfusion during the reperfusion after prolonged ischemia in skeletal muscle. Male Sprague-Dawley rats weighting 100 to 120 g were anesthetized with Nembutal. The vascular isolated rat cremaster muscle, coupled with local interarterial infusion, was the model used in this study. The diameters of feeding arterioles and terminal arterioles were measured utilizing intravital microscopy. The number of terminal arterioles with temporary cessation of flow were counted in each cremaster. Group 1: ET-dose response (8 rats)--various concentrations of ET-1 (from 10(-8) M to 10(-5) M) were infused into the cremaster to test whether this muscle was responsive to the agent in a dose-dependent manner. Group 2: ET-antagonist response (12 rats)--PD-142893, 10(-4) M (ETab receptor antagonist) plus ET-1 10(-7) M were infused into the cremaster to test whether vasospasm caused by exogenous ET-1 could be prevented by pretreatment with this specific ETab receptor antagonist. Group 3: ischemia/reperfusion response (12 rats)--PD-142893, 10(-4) M was infused into the cremaster before ischemia (4 hr warm ischemia) and during reperfusion to test whether ETab receptor antagonism was effective in preventing the vasospasm associated with ischemia/reperfusion injury. The results from this study show that a mixed ETab endothelin antagonist, PD-142893, infused before ischemia and during reperfusion at a dose which virtually abolished the vasoconstriction produced by a high concentration of exogenous endothelin-1, had no effect on ischemia/reperfusion-induced vasoconstriction in this model. These results suggest that ET-1 probably does not contribute to the ischemia/reperfusion-induced vasoconstriction and poor reflow in rat skeletal muscle.     

Salbutamol enhances isotonic contractile properties of rat diaphragm muscle

The effects of the beta2-adrenoceptor agonist salbutamol (Slb) on isometric and isotonic contractile properties of the rat diaphragm muscle (Diamus) were examined. A loading dose of 25 microg/kg Slb was administered intracardially before Diamus excision to ensure adequate diffusion. Studies were then performed with 0.05 microM Slb in the in vitro tissue chamber. cAMP levels were determined by radioimmunoassay. Compared with controls (Ctl), cAMP levels were elevated after Slb treatment. In Slb-treated rats, isometric twitch and maximum tetanic force were increased by approximately 40 and approximately 20%, respectively. Maximum shortening velocity increased by approximately 15% after Slb treatment, and maximum power output increased by approximately 25%. During repeated isotonic activation, the rate of fatigue was faster in the Slb-treated Diamus, but both Slb-treated and Ctl Diamus fatigued to the same maximum power output. Still, endurance time during repetitive isotonic contractions was approximately 10% shorter in the Slb-treated Diamus. These results are consistent with the hypothesis that beta-adrenoceptor stimulation by Slb enhances Diamus contractility and that these effects of Slb are likely mediated, at least in part, by elevated cAMP.     

Effects of guan-fu base a on experimental cardiac arrhythmias and myocardial contractility

Guan-fu base A (GFA) is a terpenoid alkaloid isolated from the tuber of Aconitum coreanum in our institute. GFA (20-30 mg.L-1) reduced the ventricular tachycardia (VT) and ventricular fibrillation (VF) rate induced by K(+)-free and high Ca2+ solution in Langendorf heart of rats. Pretreatment of conscious rats with GFA 2.5-10 mg.kg-1 iv, increased the amount of beiwutine necessary to produce arrhythmias. Ouabain-induced VT in conscious dogs was reverted to sinus rhythm in 1-2 min by iv GFA 9-10 mg.kg-1. GFA 10-20 mg.kg-1 iv was also found to be effective in protecting anesthetized dogs from atrial fibrillation induced by topical application of ACh. GFA 10 mg.kg-1 iv obviously decreased heart rate and prolonged the P-R interval, but slightly affected the myocardial contractility in anesthetized dogs. GFA showed no obvious effect on stroke volume and cardiac output in conscious dogs. In conclusion, GFA showed therapeutic and prophylactic effect on different models of experimental arrhythmias without causing marked effect on myocardial contractility.     

Comparison of antihypertensive effects of nicardipine with nitroglycerin for perioperative hypertension

BACKGROUND: To compare the efficacy of intravenous (iv) nicardipine with nitroglycerin for the treatment for patients with perioperative hypertension. METHODS: Forty patients with perioperative hypertension randomly divided into two groups were treated with intravenous calcium entry blocker, nicardipine, or vasodilator, nitroglycerin. Haemodynamic measurements including mean arterial and pulmonary arterial pressure, central venous and pulmonary capillary wedge pressure, and cardiac output were recorded; peripheral and pulmonary vascular resistance were calculated. RESULTS: Both medications were effective in reducing blood pressure and controlling haemodynamics. During the maintenance by continuous iv infusion, nicardipine controlled hypertension more rapidly than nitroglycerin (nicardipine 10.5 +/- 2.5 min and nitroglycerin 18.7 +/- 2.8 min, p < 0.05) without significant alteration in heart rate. The total frequency of dose adjustments required to achieve therapeutic response was significantly less in the nicardipine-treated group (2.5 +/- 0.3 for nicardipine and 6.2 +/- 1.4 for nitroglycerin, p < 0.05). Incidence of hypotensive episodes during the infusion were observed in both groups [nicardipine 5% (1/20) and nitroglycerin 30% (6/20), p < 0.05]. CONCLUSIONS: Intravenous nicardipine is as effective as nitroglycerin in the treatment of perioperative hypertension. Specific advantages have been identified such as stable dose-response effect, less hypotensive and tachycardial effects during the use of iv nicardipine in treatment of hypertensive patients.     

Different starting times of alpha-tocopherol and gamma-tocotrienol supplementation and tumor marker enzyme activities in the rat chemically induced with cancer

1. alpha-Tocopherol (alpha-T) and gamma-tocotrienol (gamma-T) were supplemented continuously for 8 weeks in the diets of normal rats and rats chemically induced with cancer using diethylnitrosamine (DEN), 2-acetylaminofluorene (AAF) and partial hepatectomy. Hepatocarcinogenesis was followed by determining the plasma gamma-glutamyl-transpeptidase (GGT) and alkaline phosphatase (ALP) activities as well as placental glutathione S-transferase (PGST) and GGT activities histochemically, at 4-week intervals. 2. Male Rattus norvegicus were supplemented alpha-T and gamma-T at two different doses of 30 and 300 mg/kg diet. The supplementation was started at three different times: simultaneously with DEN administration; 4 weeks; and 8 weeks after DEN administration. 3. Elevation of plasma GGT activities and formation of PGST and GGT positive foci were attenuated significantly (P < 0.05) when alpha-T and gamma-T were supplemented simultaneously with cancer induction. Supplementation begun 4 and 8 weeks after cancer induction did not affect plasma enzyme activities and formation of enzyme-positive foci. 4. alpha-T was more effective than gamma-T, and a lower dose of 30 mg/kg was found to be more effective in reducing the severity of hepatocarcinogenesis.