Increased sensitivity to natural killing in Raji cells is due to effector recognition of molecules appearing on target cell membranes following EBV cycle induction

Previous studies demonstrated that NK resistant Epstein-Barr virus (EBV) carrying human lymphoblastoid cell lines become sensitive to NK cell-mediated destruction following induction of the viral cycle by superinfection with the P3HR-1 substrain of EBV or chemicals. In the present report we analysed the cellular membrane changes that were related to the development of sensitivity to NK activity in Raji cells with metabolic inhibitors. NK sensitivity does not develop in P3HR-1 superinfected Raji cells that are cultured in the presence of the RNA synthesis inhibitor actinomycin D and drops to half the amount usually detected in superinfected cells that are grown with the protein synthesis inhibitor cyclohexamide. In experiments with cyclohexamide blocks removed after 24 h, the target cell sensitivity to NK returns to normal levels. Control Raji cells cultured with the same inhibitors for up to 72 h do not develop any sensitivity to NK cell activity. These findings suggest that the development of sensitivity to NK destruction in Raji cells following superinfection is due to the addition to the cell membrane of a virally promoted molecule(s) that requires active RNA and protein synthesis.

Massive gastric hemorrhage: an unusual complication of Henoch-Schönlein purpura

Two severely ill children with multisystem involvement of Henoch-Schönlein purpura developed massive upper gastrointestinal hemorrhage, requiring operative ligation of gastric stress ulcers, and vagotomy and pyloroplasty. Arteriographic embolization was also used in one of the children when she developed recurrent hemorrhage. Survival in both children emphasizes the need for aggressive management of the many complications these children may develop.

Ten-year oral toxicity study with Norlestrin in rhesus monkeys

The long term effects of the oral contraceptive, Norlestrin, were evaluated in sexually mature female rhesus (Macaca mulatta) monkeys over a 10 year period. Norlestrin, a combination of norethindrone acetate and ethinylestradiol (50:1) was given orally on a continuous cyclic regimen of 21 d of dosing followed by 7 d without treatment. Groups of 16 monkeys each received the drug at dose levels of 0.05, 0.51, and 2.55 mg/kg representing multiples of 1, 10, and 50 times the human dose, respectively. A comparable group of 16 animals remained untreated and served as controls. Selected clinical and laboratory parameters were monitored throughout the study and all animals were necropsied and evaluated for gross and histopathologic changes. All dose levels were well tolerated and survival was not affected. There were no consistent treatment-related alterations in coagulation or other clinical laboratory parameters. Ophthalmologically, macular pigmentary anomalies were observed in all groups. Treatment-associated pathologic findings, representing exaggerated pharmacological responses with superimposed senile changes, including ovarian and uterine atrophy and dilatation of acini and ducts in the mammary gland. Periodic vaginal cytologic examination and mammary gland palpation did not demonstrate drug related changes. A small number of neoplasms was seen in all groups and a granulosa cell carcinoma of the ovary occurred in a control animal. The benign tumors consisted of three cutaneous papillomas: one in a low dose and one in a high dose animal, a uterine leiomyoma in one high dose animal, and a pancreatic duct adenoma in one low dose animal. The results of this study indicate that Norlestrin had no significant toxic manifestations or tumorigenic potential when administered on a cyclic regimen to female rhesus monkeys at levels up to 50 times the human dose for ten yr.

Growth and sexual maturation in ewes: the role of photoperiod, diet and temperature on growth rate and the control of prolactin, thyroxine and luteinizing hormone secretion

The relationship of photoperiod, temperature and diet on growth rate and serum concentrations of thyroxine (T4), prolactin (PRL) and luteinizing hormone (LH) were studied in ewe lambs from 9 to 32 wk of age. Lambs reared on a diet supplying 1.78 Kcal/g net energy had higher (P less than .025) serum T4 concentrations and greater average daily gain (ADG) than lambs fed a lower energy ration (1.5 Kcal/g). Long artificial photoperiod of 16 h of light neither improved ADG nor altered T4 concentrations compared with ambient (natural light) or a short artificial photoperiod of 8 h light. Serum PRL concentrations were correlated (r = .83 to .74; P less than .01) to ambient temperature during the seasonal transition from summer to fall and temperature also determined the magnitude of photoperiodic stimulation of PRL levels in winter. Temperature had no effect on basal LH concentrations for lambs kept in warm (15 to 20 C) vs cold (0 to 15 C) environments for 6 wk, but the LH surge induced by estradiol was delayed (P less than .05) by the warm environment. The correlation (r = .015) between serum PRL levels and ADG was not significant, although serum PRL concentrations were dependent upon dietary energy levels. These observations do not support a positive relationship of PRL or photoperiod to ADG in the ewe lamb.

A clinical experience with the NCGT graft

A comparison of 130 grafts done in 101 patients included 47 veins, 25 Johnson & Johnson dialdehyde-starch-tanned collagen prostheses, and 58 NCGT grafts that had been followed for a 40-month period. This study had documented the fact that in spite of frequent poor runoff, a useful result is provided by the NCGT graft apparently due in part to its built-in nonthrombogenic structure providing a cumulative patency of 73%. The patency rate was even superior with venous bypasses. Therefore, we still feel that the autogenous vein provides the most useful bypass conduit available in vascular reconstruction. In situations where a vein could not be used or was not available the NCGT graft offers an equally useful nonthrombogenic surface to maintain prolonged patency. Thus, collagen appropriately modified can provide a useful prosthesis in vascular reconstruction.

A new effective intraoperative hemostat - Superstat

A new effective solvating hemostatic agent, Superstat, has been developed and evaluated in animals and man. It appears to work in part because of its large electron absorbing surface and in part due to the physiologic concentration of contained calcium. The available information from the first 130 patients in which it has been evaluated suggest that it has few, if any, side effects, leaves no residue following use, and is an extremely effective hemostat under most conditions and in all tested operative areas in man. Available data indicate that it has local effects which represent biochemical and ultra-structural interactions with shed blood.

Long-term function of NCGT vascular conduits in a multicenter trial: evaluation of physical chemical parameters

Our experience with the NCGT graft has now encompassed 12 years in experimental animals and 4.5 years clinical experience with 134 grafts in man. It has previously been suggested that vessel wall structure, interface-charge, electric potential, and polarity of the blood intimal interface appear critical in the prevention of intravascular thrombosis in all vascular prosthetic bypass grafts. This concept has now been confirmed using ferritin, colloidal iron and fluorescamine intimal labelling. These provide a quantitative special characterization of the surface charges of several grafts, including the NCGT graft. Study indicates that each step in the production of the NCGT graft results in a cumulative increase in the structured negative charge of the vascular interface. The more dense the structured negative charge of the prosthesis, the more resistant is the graft to short and long-term thrombosis in experimental animals and man. The experience has been confirmed with a comparative analysis of implantation results in 105 patients up to 4.5 years with 65 to 70% patency rate over that time interval. Statistical analysis of parameters confirm again that the polarity and structure of the vascular interface is important in the effective function and patency rate of the grafts.

Diencephalic syndrome and its relation to opticochiasmatic glioma: review of twelve cases

This report, which includes 12 cases of opticochiasmatic glioma with diencephalic syndrome, is a 22-year review of such cases at Indiana University Medical Center. These patients were initially seen because of their failure to thrive, and all were without significant subcutaneous fat. All had pneumoencephalography or ventriculography that showed a suprasellar mass displacing the anterior 3rd ventricle. Surgical confirmation of the diagnosis was obtained in every case. Ten patients underwent radiotherapy with subsequent reversal of the diencephalic syndrome.

pH homeostasis during cardiopulmonary resuscitation in critically ill patients

We investigated the effect of repeated administration of sodium bicarbonate on acid-base balance and serum chemistry in a group of patients who developed cardiac arrest. A mixed acidosis persisted throughout the duration of resuscitation in the majority of patients in spite of the large ventilatory volume and multiple doses of bicarbonate they received. However, the repeated administration of bicarbonate prevented a severe fall in serum pH. Our study demonstrated the beneficial role of bicarbonate in the treatment of metabolic acidosis associated with cardiac arrest of prolonged duration. Analysis of our data strongly indicated that the primary factors which determine the serum pH during cardiopulmonary resuscitation are the duration of circulatory arrest, adequacy of ventilation and circulation, pH immediately before arrest, and quantity of bicarbonate administered and its volume of distribution in the various fluid and tissue compartments.

Response optimization of drug dosage: antiarrhythmic studies with tocainide

The benefits of using antiarrhythmic response to optimize dosage regimens of antiarrhythmic drugs in individual patients have been examined. Graded antiarrhythmic response and simultaneously measured plasma drug concentrations have been obtained in 15 patients receiving multiple oral doses of a new antiarrhythmic, tocainide. Plasma drug concentration-antiarrhythmic response data from each of 11 subjects responding to the drug have been fitted by a generalized concentration effect function which is valid over the entire range of response. With the use of experimentally determined pharmacokinetic parameters to define the dose-plasma concentration relationship and plasma drug concentration-response parameters estimated for individual patients, simulations were carried out to show the effect of various dosage regimens on antiarrhythmic response in individual patients. Such simulations provide a means of assessing antiarrhythmic effect in the range of clinical interest (80% to 100% of maximum effect), where the antiarrhythmic effect is a nonlinear function of dose, plasma drug concentration, or their logarithms. The simulations also demonstrate that for identical daily doses and dosing intervals patients show marked variability in antiarrhythmic response.

The assessment of mitral stenosis and prosthetic mitral valve obstruction, using the posterior aortic wall echocardiogram

The echocardiographic motion of the aortic root reflects, in part, left atrial filling and emptying. Patients with mitral valve obstruction were studied to determine whether clinically important alterations in patterns of left atrial emptying would alter motion of the posterior aortic wall. Patients with mitral stenosis had a characteristic pattern of slowing of left atrial emptying in early diastole, with loss of the conduit phase in mid-diastole. The atrial emptying index, defined as the fraction of passive posterior aortic wall motion occurring in the first third of diastole, was significantly related to the mitral valve area index (r = 0.86), and thus provides a noninvasive quantitation of the degree of mitral stenosis. Determination of the atrial emptying index also proved useful in the evaluation of patients with prosthetic mitral valve obstruction and in documenting improvement in left atrial emptying after mitral valve surgery.

Hemodynamic changes at the onset of spontaneous versus pacing-induced angina

To determine the origin of angina pectoris at rest hemodynamic monitoring was performed for 24 to 72 hours in 25 patients with unstable angina who had pacing-induced angina during cardiac catheterization. During the monitoring period, seven patients had spontaneous epidsodes of angina at rest that could be compared with the pain-free periods and periods of pacing-induced angina. At the onset of spontaneous angina, the patients had a significantly lower mean double product (P is less than 0.005) and triple product (P is less than 0.025) than at the onset of pacing-induced angina. The mean double product (heart rate x systolic blood pressure) was 9,411 +/- 2,815 mm Hg/min during pain-free rest, 10,635 +/- 2,587 at the onset of spontaneous angina and 16,623 +/- 3,904 during pacing-induced angina. The mean resting pain-free triple product (heart rate x systolic blood pressure x ejection time) was 3,023 +/- 703 and 3,536 +/- 931 mm Hg/sec per min during, respectively, pain-free rest and spontaneous angina, and 4,350 +/- 938 mm Hg/sec per min during pacing-induced angina. These marked differences in the double and triple products were associated with a mean increase in pulmonary arterial diastolic pressure (from 10.7 mm Hg at rest to 14 mm Hg) at the onset of both spontaneous and pacing-induced angina. Although indirect, these data suggest that transient changes in coronary blood flow, rather than changes in myocardial work, may be primarily responsible for spontaneous angina at rest in certain patients with the syndrome of unstable angina.

Afterload reduction in the management of postinfarction ventricular septal defect

The primary goal in the medical management of ventricular septal defect complicating myocardial infarction is to support cardiac function and control symptoms, if possible, for a period of 4 to 6 weeks. If the patient survives this period, surgical correction of the defect is technically easier and safer. In many cases, However, cardiac function is severly compromised, intractable biventricular failure develops,early operation is necessary and the likelihood of successful repair is diminished.

Diagnosis and quantification of arrhythmias in ambulatory patients using an improved R-R interval plotting system

An improved technique for identification, diagnosis and quantification of arrhythmias during rest or ambulatory electrocardiographic recording is described. With simultaneous plotting of the R-R interval and the QRS duration and QRS vector measurement of each beat versus time, all periods of arrhythmias or abnormal complexes can be identified and characterized. Analog electrocardiographic samplings are used to confirm the diagnosis of the arrhythmia and to exclude artifact. The availability of a permanent record for the characterization of each QRS complex enables the physician to check the technician's analysis of the recording and to relate all events to the patient's heart rate and clinical symptoms. This technique also provides data for quantification of ventricular arrhythmias.