Defective interleukin 2 receptor expression is associated with the T cell disfunction subsequent to bone marrow transplantation

In the present work we have used monoclonal antibodies (mAb) as probes to attempt a dissection of the mechanisms underlying the immunodeficiency subsequent to bone marrow transplantation (BMT). To this end we have studied 19 allogeneic BMT recipients, analyzing the proliferative response of peripheral blood mononuclear cells (PBMC) after activation with either phytohemagglutinin (PHA), anti-CD3 or anti-CD2 mAb. All patients presented normal proportions of CD2+ and CD3+ lymphocytes, as assessed by flow cytometry. Our results indicated that in most cases both CD2 and CD3-mediated activation pathways were inefficient to trigger normal T cell proliferation. The addition of exogenous interleukin 2 (IL2) did not restore in most cases the proliferative response, pointing out that additional defects contribute to the hyporesponsiveness. This was more evident in the group of patients studied during the first 6 months. To further dissect the T cell defect we analyzed the effect of a phorbol ester (phorbol myristate acetate, PMA), which activates protein kinase C, on the anti-CD3-induced response. Our data showed that PMA synergized with anti-CD3 similarly to exogenous IL2, and restored the proliferative response only in certain cases. The expression of IL2 receptors (CD25) as assessed by cytofluorimetry, after either PHA or anti-CD3 and PMA stimulation, was shown to be depressed, and the addition of IL2 did not restore it. Finally, we observed that the early increase of intracytoplasmic Ca2+ after anti-CD3 stimulation was comparable to that detected in normal PBMC. Altogether these results indicate that a diminished CD25 expression is associated with the T cell defect, and cannot apparently be attributed to an inability of the CD3 molecule to transduce early activation signals thus suggesting that either protein kinase C itself or an as yet undefined metabolic step preceding IL2 receptor expression is abnormal in variable proportions of T cells after BMT, and constitutes another manifestation of this complex immunodeficiency.

[Ruptured adenoma of the liver with severe pulmonary embolism discovered during a cesarean section]

A ruptured adenoma of liver was detected during a caesarean in a multipara woman at full term with a severe pulmonary embolus. Therapy for this rare and curious case, with combined internal hemorrhage, severe pulmonary embolism and full term pregnancy in a multipara, is discussed.

Variability of the haemodynamic responses to laboratory tests employed in assessment of neural cardiovascular regulation in man

In man evaluation of neural cardiovascular regulation makes use of a variety of tests which address the excitatory and reflex inhibitory neural influences that control circulation. Because interpretation of these tests is largely based on the magnitude of the elicited haemodynamic responses, their reproducibility in any given subject is critical. In 39 subjects with continuous blood pressure (intra-arterial catheter) and heart rate monitoring we measured the blood pressure and heart rate rises during hand-grip and cold-pressor test, the heart rate changes occurring during baroreceptor stimulation and deactivation by injection of phenylephrine and trinitroglycerine, and the heart rate and blood pressure changes occurring with alteration in carotid baroreceptor activity by a neck chamber. Each test was carefully standardized and performed at 30 min intervals for a total of six times in each subject. The results showed that the responses to any test were clearly different from one another and that this occurred in all subjects studied. For the group as a whole the average response variability (coefficient of variation) ranged from 10.2% for the blood pressure response to carotid baroreceptor stimulation to 44.2% for the heart rate response to cold-pressor test. The variability of the responses was not related to basal blood pressure or heart rate, nor to the temporal sequence of the test performance. Thus tests employed for studying neural cardiovascular control in man produce responses whose reproducibility is limited. This phenomenon may make it more difficult to define the response magnitude typical of each subject, as well as its comparison in different conditions and diseases.

Endoscopic placement of enteral feeding tubes

The techniques for placement of feeding tubes using fiberscopes are described and an evaluation of the results obtained in the last 12 months is made. The techniques are discussed and compared with other methods of enteral feeding known at present. It is concluded that placement of feeding tubes by endoscopy can be achieved easily, that it is possible to choose the site of enteric liberation of nutrients under conditions which previously represented contraindications, and that this procedure is free of complications even during long periods of time.

Deep venous thrombosis: diagnosis in spinal cord injured patients

Because the acute spinal cord injured patient is at high risk for the development of deep venous thrombosis (DVT), accurate diagnosis is critical. Clinical evaluation is unreliable 50% of the time, however, and the two highly accurate diagnostic procedures--venography and 125I-labelled fibrinogen scanning--are invasive and present serious drawbacks. The literature concerning the effectiveness of the two most widely used noninvasive diagnostic alternatives (Doppler ultrasound and venous occlusion plethysmography [VOP]) is equivocal. In our systematic evaluation of a series of 21 patients, using clinical examination, Doppler ultrasound and VOP, all patients who developed DVT were identified by all three methods. Overall accuracy, sensitivity and specificity were 100%.

Thymopentin treatment in patients with chemotherapy-resistant lepromatous leprosy

Leprosy is a chronic infectious disease caused by Mycobacterium leprae; it is chiefly involving the skin and peripheral nerves. In lepromatous leprosy there are widespread loose infiltrates with M. leprae multiplying extensively in the skin macrophages and Schwann cells of peripheral nerves. Such patients reveal a decrease of circulating T helper cells, which is still more pronounced in the cutaneous lesions. Due to the ever increasing bacterial resistance to classical dapsone and combined chemotherapy as well, an immunomodulatory approach seemed reasonable: Eight patients with long-lasting (5-40 years) disease who had become resistant to combined chemotherapy were treated with thymopentin, 50 mg s.c., 3 times weekly for 5 weeks and thereafter combined with dapsone and clofazimine for 5 months. During the trial a statistically significant increase in E-rosette-forming cells (p less than 0.05) was observed, along with a steady improvement of the bacterial status of the nasal mucus. Although the skin lesions did not disappear within the observation period of the study, it is important to realize that long-term improvement of such lesions is always initiated by clearance of bacilli from the nasal mucus, hence, thymopentin treatment appears to be a promising approach to chemotherapy-resistant lepromatous lepra.

Haemodynamic effects of enalapril, a new converting enzyme inhibitor, in hypertensive patients

The haemodynamic effects of enalapril (EN), a new, long-acting, nonsulphhydryl converting enzyme inhibitor, were evaluated by non-invasive methods in 10 adult patients with mild to moderate essential hypertension (EH). Patients were randomly assigned, double blind to 2 treatment groups (EN 20 mg o.d. or 10 mg b.d.) for 4 weeks, and were crossed over to the other dosage regimen after a 2-week washout period. Measurements included mean arterial pressure (MAP), heart rate (HR), cardiac output (CO), limb blood flow (LBF), plasma aldosterone (ALD), plasma renin activity (PRA) and systolic time intervals (STI). Both regimens (b.d. and o.d.) significantly reduced MAP (15.3% and 16.3%, respectively), total peripheral resistance (20.3% and 21.8%, respectively), limb vascular resistance (24.1% and 24.9%) and ALD (33.5% and 36.9%) and increased CO (7.8% and 8.7%), LBF (10.9% and 11.6%) and PRA (10.4% and 9.5%). No significant change was observed in HR or STI. EN 20 mg o.d. or 10 mg b.d. reduced arterial pressure to a similar extent through a fall in total peripheral resistance. An increase in CO was also observed.

Role of cardiopulmonary receptors in reflex control of renin release in man

Animal studies have shown that renin release is reflexly modulated by cardiopulmonary and arterial baroreceptors, and that during changes in posture the former receptors play a major role. This role has been challenged in man, however, by reflex modulation of renin secretion which has been claimed to take place only if arterial and cardiopulmonary receptor areas are engaged together. We studied 19 normotensive and essential hypertensive subjects in which plasma renin activity was assessed by radioimmunoassay during a mild 20 min increase and a mild 20 min reduction in central venous pressure (+1.1 +/- 0.2 mmHg and -2.6 +/- 0.4 mmHg). The increase and reduction in central venous pressure were accompanied by no change in systolic blood pressure, diastolic blood pressure and heart rate which indicated that the increased and reduced stimulus had involved only cardiopulmonary receptors and not arterial baroreceptors as well. During the increase in central venous pressure plasma renin activity showed a significant (P less than 0.01) reduction (-18 +/- 3%) whereas during the reduction in central venous pressure it showed a significant (P less than 0.01) and more marked increased (+64 +/- 17%). The plasma renin activity increase observed during lower body suction was not significantly different from that observed during a 20 min tilting, a manoeuvre that reduced central venous pressure to an extent similar to that observed during lower body suction, but that also deactivated carotid baroreceptors by positioning the carotid sinuses above the heart and reducing their transmural pressure. Thus in normotensive and hypertensive humans renin release can be reflexly modulated by selective engagement of cardiopulmonary receptors.(ABSTRACT TRUNCATED AT 250 WORDS)

Systemic and cardiac haemodynamic interactions between guanfacine and hydrallazine in hypertensive patients

The effect of guanfacine and hydrallazine on cardiovascular haemodynamics and on sympathetic nervous activity has been studied in 16 patients with essential hypertension. Two groups of patients were investigated: in Group A guanfacine brought the blood pressure back to normal (diastolic blood pressure less than or equal to 90 mmHg), and in Group B diastolic blood pressure was greater than 90 mmHg and required the addition of hydrallazine. Guanfacine significantly decreased heart rate, plasma renin activity and urinary excretion of noradrenaline, without altering cardiac contractility. In Group B, guanfacine 2 to 6 mg/day produced a significant decrease in blood pressure from 178.7/112.4 to 164.4/102.9 mmHg and in heart rate from 77.1 to 62.7 beats/min after 4 weeks of treatment. Guanfacine did not significantly alter preejection period, cardiac output or total peripheral resistance. Hydrallazine 50 to 300 mg/day caused a further reduction in blood pressure from 164.4/102.9 to 150.7/90.2 mmHg and an increase in heart rate from 62.7 to 72.1 beats/min. Limb blood flow was increased from 4.55 to 5.93 ml/100 g/min and limb vascular resistance was decreased from 39.55 to 23.6 mmHg 100 g X min/ml. Hydrallazine also caused a slight increase in plasma renin activity and urinary excretion of noradrenaline. It is concluded that guanfacine is a useful agent to block a hydrallazine-induced increase in sympathetic nervous activity.

Reproducibility of laboratory tests evaluating neural cardiovascular regulation in man

In 31 normotensive and hypertensive subjects with continuous intra-arterial blood pressure (BP) and heart rate (HR) monitoring, we examined the short term reproducibility of the haemodynamic responses to a number of tests commonly employed in studies on neural cardiovascular regulation: (1) hand-grip exercise and cold pressor tests that increase BP and HR through central and reflex mechanisms; (2) bolus injections of phenylephrine and trinitroglycerine that reflexly reduce and increase HR through stimulation and inhibition of arterial baroreceptors; (3) negative and positive pressure alterations within a neck chamber that reflexly reduce and increase BP through stimulation and inhibition of carotid baroreceptors. Each test was standardized and repeated at 30 min intervals six times in each subject. In the group as a whole the BP and HR responses to hand-grip showed a variability (mean variation coefficient, VC) of 22 and 25% respectively. BP and HR responses to cold pressor test showed a VC of 17 and 44% and HR responses to trinitroglycerine showed a VC of 28%. HR responses to phenylephrine were slightly less (19%) and BP responses to neck chamber considerably less variable (14 and 10%). The variability of the responses was not related to basal BP or HR or to the time sequence of the tests. Thus, tests commonly employed for studying neural cardiovascular control in man have a limited short-term reproducibility. This implies that caution should be used in interpreting results obtained by a single performance of any given test, and in comparing results in different states or groups such as normotensive and hypertensive subjects, unless a relatively large number of responses is available.

Mechanisms of antihypertensive action of beta-adrenergic blocking drugs: evidence against potentiation of baroreflexes

A possibility that can be advanced to explain the antihypertensive effect of beta-blocking drugs is that they act through the baroreflex control of the cardiovascular system. In 38 essential hypertensive patients we measured 1) The lengthening and shortening in R-R interval caused by stimulation or deactivation of arterial baroreceptors (vasoactive drug technique); 2) The fall and rise in blood pressure caused by stimulation and deactivation of carotid baroreceptors (neck chamber); 3) The rise in forearm vascular resistance caused by deactivation of cardiopulmonary receptors (lower body suction). The study was made before and after 6-10 days' administration of nadolol (80-360 mg once a day) or acebutolol (200-600 mg t.i.d.). Nadolol and acebutolol similarly reduced blood pressure and heart rate. Either drug increased heart rate responses to arterial baroreceptor manipulation but the increase fell short of statistical significance. Blood pressure and vasomotor responses to carotid baroreceptor and cardiopulmonary receptor manipulation were also not significantly modified by beta blockade. The baroreceptor control of heart rate and blood pressure showed a modification, however, insofar as a resetting towards the lower blood pressure values occurred. These findings demonstrate that arterial baroreceptor and cardiopulmonary receptor control of circulation is not potentiated by beta-blocking drugs, and that therefore this mechanism cannot account for their antihypertensive effect. The resetting of the baroreflex that occurs during beta blockade may, however, contribute to maintain the hypotension obtained.

Cerebral protection in carotid surgery

We performed 956 carotid endarterectomies in 661 conscious patients who were under cervical block anesthesia and in whom the stroke rate was 2.5%. They were analyzed to determine the mechanisms of strokes and the risk factor for perioperative stroke. Twenty-three patients with perioperative strokes, regardless of severity, were analyzed as to the mechanism of cause. One half were due to technical problems, one quarter to intraoperative embolization, one sixth to intracerebral hemorrhage, and the remainder were not directly related to the operative procedures. Perioperative stroke rate varied by group from 0.6% to 28.4%, highest when the contralateral carotid was occluded, where there was a preoperative persistent neurologic deficit, and when the patient failed to tolerate carotid clamping. Regional block monitoring was accurate and no stroke could be ascribed to anesthetic technique. Standard reporting techniques should be used in classifying patients into appropriate risk groups to permit meaningful comparisons among groups using different techniques for cerebral protection.

Pulmonary circulation of the llama at high and low altitudes

We have studied the pulmonary circulation of three closely related animals, the llama, alpaca, and guanaco. The mean pulmonary arterial pressure of 12 llamas and one alpaca indigenous to high altitude in the Andes was found to be slightly but significantly higher than that of three llamas and three guanacos born and bred at low altitude in England. On the other hand, the medial thickness of the muscular pulmonary arteries and the relative weights of the two ventricles were the same in three llamas and one alpaca at high altitude as they were in one llama and two guanacos at low altitude. It is concluded that the pulmonary vasoconstrictive response to hypoxia, while present, is greatly reduced in this species and it is suggested that this may have taken place by evolutionary adaptation.

Effects of high-frequency harmonics on cardiac relaxation indices

This study was designed to determine the degree to which the systematic distortions in the pressure curve due to recording and filtering systems influence the relaxation indices. The purposes are 1) to analyze the dependency on the high frequencies of the relaxation and contractility parameters, 2) to determine the degree to which the catheter recordings modify those parameters, and 3) to test the monoexponential hypothesis in which the T index is based (Weiss, Frederiksen, and Weisfeldt, J. Clin. Invest. 58: 751-760, 1976). In 17 open-chest dogs, the left ventricular pressure (LVP) was recorded in four different ways: 1) with a large-bored metal cannula, 2) with a catheter-tip manometer, 3) with a Cournand catheter, and 4) with a pigtail catheter. The ECG and LVP were digitized by a computer. A Fourier analysis was performed, and the LVP waves were resynthesized with different numbers of harmonics. We conclude that 1) the catheter recordings are not recommended to calculate relaxation indices, 2) relaxation parameters present more sources of errors than contractility parameters, 3) the monoexponential hypothesis of T is fulfilled if the isovolumic relaxation is considered to end at the time the LVP is 10 mmHg more than left ventricular end-diastolic pressure level, 4) the dependency on higher harmonics of T index and +dP/dtmax is similar, and 5) -dP/dtmax is much more high-frequency dependent than T index.

Correlates and changes over time in drug and alcohol use within a barrio population

Extent and determinants of use of alcohol, marijuana, inhalants, and PCP were explored in a group of 339 Mexican American youths from the East Los Angeles Housing projects. Results from this study were compared to those from a similar survey carried out in the same area 2 years ago. Use of inhalants has declined markedly compared with prevalence reported in the previous report. However, use of alcohol and marijuana have increased across all age and sex cohorts. Prevalence of PCP use, explored for the first time in this report, was shown to be extremely high. Use of all drugs was generally predicted by age, sex, and number of peers reporting use. Self-concept factors, especially one's self-evaluation with respect to others, were also significant predictors to use of marijuana, inhalants, and PCP. However, alcohol use was not related to any self-concept factors. Language (Spanish-English) used both in the home and with peers was related to use of all substances studied. Limitations in the generalization of this study as a result of sampling problems are discussed.

Echocardiographic diagnosis of left ventricular thrombi

Left ventricular thrombi have not been commonly recognized by M-mode or by cross-sectional echocardiographic techniques despite their frequency at postmortem examination in patients dying of cardiovascular disease. We discuss two patients, with left ventricular throbmi recognized echocardiographically and confirmed by pathologic and/or angiographic evaluation, whose M-mode and cross-sectional echocardiographic abnormalities add to the variable spectrum of appearance of left ventricularl thrombi. The sensitivity and specificity of echocardiographic techniques in the diagnosis of intracardiac thrombi are discussed.

Ascending colon volvulus due to a vitelline duct remnant in an elderly patient

A 77-year old female is presented with volvulus of the ascending colon due to torsion around a vitelline duct remnant. Symptoms were mild and intermittent. Roentgenograms are presented which demonstrated this lesion preoperatively. At surgery the ascending colon was found to be twisted around a fibrous band extending from the umbilicus to the ileum.

Double-blind evaluation of chemonucleolysis for herniated lumbar discs. Late results

Sixty-six patients with symptomatic herniated lumbar discs refractory to the usual conservative management were allocated at random into one of two treatment groups according to a double-blind protocol: 31 received chymopapain intradiscally (chemonucleolysis) and 35 received a placebo intradiscally. Symptoms remained significantly improved 1 year or more after injection for 55% of those treated with chymopapain and for 46% of those treated with placebo. The difference is not statistically significant. However, to discard chemonucleolysis on the basis of this one small clinical trial may be premature. Since continuing controversy has re-established a climate in which another double-blind study of chemonucleolysis is ethically feasible and scientifically desirable, we favor additional clinical trials under a tightly controlled protocol to help resolve the issue.

[Effects of levophacetoperane, pemoline, fenozolone, and centrophenoxine on catecholamines and serotonin uptake in various parts of the rat brain]

These drugs, except centrophenoxine, inhibit in vitro in a competitive manner, norepinephrin uptake in Rat hypothalamus and cortex, and dopamine uptake in corpus striatum and cortex, at higher concentrations than d.l. amphetamine; this alone inhibits serotonin uptake in hypothalamus.

[Regional variations and particle binding of free amino acids in the rat brain: effects of amphetamine and methaqualone]

Amphetamine and methaqualone affected aspartate level in various regions of Rat brain. Increased aspartate level in cerebral cortex of methaqualone treated Rats was produced in the aspartate fraction whose binding to subcellular particules was Na+ dependant. This work suggest that aspartate level was altered only in brain fraction implicated in the pharmacological effects of the drugs.

Double-blind evaluation of intradiscal chymopapain for herniated lumbar discs. Early results

The authors report 66 patients with signs, symptoms, and a myelographic abnormality of herniated lumbar disc, who were not responsive to conservative treatment. The discs were injected at random with either chymopapain or a placebo. Neither patient nor surgeon knew which agent was used until after the results had been tabulated. Unless early laminectomy was necessary for intractable pain, all patients were followed for 2 months or more. There was no statistically significant difference in incidence or quality of improvement between the two groups: chymopapain was successful in 58% while placebo was successful in 49% (p = 0.15). Early results from this study indicate that most, if not all, of the putative effectiveness of chemonucleolysis probably derives from a placebo effect.

Attitudinal and behavioral reactions to fear-arousing communications

The present study tested the hypothesis that the relationship between fear arousal and persuasion is a curvilinear one. High-, moderate-, and low-fear messages were presented to over 900 students in 6 public schools. In addition to paper-and-pencil measures, a behavioral measure of toothbrushing was used. In general, the results did not support the curvilinear hypothesis but did tend to support studies showing a positive relationship between levels of fear and attitude change but not with respect to behavioral change. Problems dealing with the curvilinear model are discussed.

Effect of intracisternal phentolamine on cerebral blood flow after subarachnoid injection of blood

The hydrogen clearance method was used to measure total and focal cerebral blood flow (CBF) in the monkey before and for 5 hours after a simulated subarachnoid hemorrhage (SAH). Some monkeys also received 0.2 to 1.0 mg/kg phentolamine intracisternally 3 hours after SAH. Results show that SAH did not change cerebrovascular resistance, but as cerebral perfusion pressure decreased, CBF fell transiently. Phentolamine injected intracisternally 3 hours after SAH produced a significant fall in arterial blood pressure; cerebrovascular resistance did not change but CBF decreased significantly. These data indicate that intracisternal phentolamine cannot be considered potentially useful to treat ischemic encephalopathy after SAH.

The effect of a simulated subarachnoid hemorrhage on cerebral blood flow in the monkey

The hydrogen clearance method was used to measure local and total cerebral blood flow (CBF) in the rhesus monkey before and for five hours after a simulated subarachnoid hemorrhage (SAH). CBF remained stable after SAH unless SAH was associated with a fall in cerebral perfusion pressure. In addition, cerebrovascular resistance did not increase after SAH. These results suggest that vasoactive agents in fresh whole blood, and the arterial spasm they produce when added to cerebrospinal fluid (CSF), play only a limited role in the pathogenesis of ischemic encephalopathy that follows an SAH.

The effect of dexamethasone on the rate of formation of cerebrospinal fluid in the monkey

✓ The standard ventriculocisternal perfusion technique was used to determine what effect a single large intravenous dose of dexamethasone would have on CSF formation rate in the rhesus monkey over a 4-hour period. Three monkeys received 0.15 mg/kg, four received 0.4 mg/kg and five served as the untreated controls. With time, CSF formation rates decreased in both treated and control groups. The magnitude of the decrease in the treated and untreated controls did not differ significantly. We conclude that the therapeutic benefit of dexamethasone for intracranial spatial decompensation derives from a mechanism of action that leaves the rate of CSF formation unchanged.

Total cerebral blood flow in the monkey measured by hydrogen clearance

Simple hydrogen-sensitive polarographical electrodes of thin platinum wire were inserted into the torcular Herophili of Rhesus monkeys. Hydrogen was administered by inhalation for ten minutes, after which the hydrogen clearance was recorded from torcular blood. At a Paco 2 of 32 mm Hg (SD ± 2.3), flow in the fast flow compartment was 102 ml/100 gm per minute (SD ± 19.1), and flow in the slow flow compartment was 28 ml/100 gm per minute (SD ± 5.8). Mean total cerebral blood flow was 52 ml/100 gm per minute (SD ± 10.5). Coefficient of variation was less than 10%.

Our experience suggests that one may reliably measure average total cerebral blood flow in the experimental setting by following the clearance of hydrogen from torcular blood. The method is relatively simple, inexpensive and radiation-free. It can be easily combined with the standard hydrogen clearance technique for measuring local tissue blood flow, thereby permitting the simultaneous recording of both local and total brain blood flow.