Genes of renin angiotensin system and coronary heart disease

Coronary constriction, proliferation of smooth muscle cells and arrhythmia are involved in the pathophysiology of coronary heart disease and its complications such as myocardial infarction and sudden death. All these effects are favoured by high angiotensin II levels. Angiotensin II is the main effector molecule of the renin angiotensin system and it acts through angiotensin II type receptors. Genetically determined differences in the expression of the components of this system could adversely affect angiotensin II concentration and subsequently heart. Consequently each component of this system represents a potential candidate in the etiology of cardiovascular disease. In this article we review the variation of the angiotensin I converting enzyme, angiotensin II type I receptor and angiotensinogen genes and their association with cardiovascular disease.

Characterisation of the canine cardiac sarcolemma in experimental myocardial ischemia

The cardiac sarcolemma was characterized in 13 normal and 11 ischemic dog hearts by enzyme analysis and compositional assays. Significant decreases in the activities of the sodium-potassium and calcium pumps and structural compositional disturbances were observed in ischemia. High concentrations of oleic acid, a fatty acid and palmitoyl carnitine, a fatty acid intermediate caused inhibition of the enzyme pump activities of the normal sarcolemma. Thus, ischemia results in the functional impairment of the sarcolemma. Accumulation of fatty acid and fatty acid intermediates, occurring in myocardial ischemia, could be an underlying mechanism.

Platelet polymorphisms: frequency distribution and association with coronary artery disease in an Indian population

Platelets play a critical role in normal blood hemostasis and thrombus formation in myocardial infarction (MI). Several polymorphisms of genes involved in platelet activation and fibrinolysis have been reported to be associated with MI. The aim of the present study was to determine the frequency distribution and association of polymorphisms in these genes with coronary artery disease (CAD) among Indians. A case-control genetic association study was performed for polymorphisms in platelet glycoprotein receptors (GPIIb/IIIa [HPA1a/1b], GPIb-IX-V [VNTR], and GPIa/IIa [C807T]), fibrinogen β-chain (BclI), α-chain (Aα312), tissue plasminogen activator (tPA) [I/D] and plasminogen activator inhibitor-I (PAI-1) [4G/5G] in 473 healthy controls and 446 patients with stable and unstable angina. Genotyping was either by PCR-based restriction endonuclease digestion or allele-specific primers. The I allele frequency of the tPA I/D polymorphism was significantly higher in our patients (χ(2)=7.33, P<0.01) and no other polymorphisms varied significantly between patients and controls. Also, none of the polymorphisms seemed to affect the severity of the disease, the only exception being the mutant alleles of β chain of fibrinogen gene, which were significantly elevated in single vessel disease. This is the first study to evaluate the role of gene polymorphisms in both the thrombotic and fibrinolytic pathway in the Indian population and suggests that tPA I/D polymorphism confers CAD risk in our population.

Further observations on the polynucleotide-induced stimulation of protein synthesis by cell-free preparations from rabbit reticulocytes

1. The effect of high-molecular-weight RNA from reticulocyte polyribosomes (messenger RNA) on protein synthesis by subcellular fractions derived from reticulocytes, reported by Arnstein, Cox & Hunt (1964), has now been studied in detail. Optimum response of the cell-free system requires 30-50mm-K(+) and approx. 5mm-Mg(2+) in the pH range 7.4-7.6. 2. RNA stimulates the incorporation into protein of both free amino acids and of aminoacyl residues from s-RNA. Stimulation by either RNA or polyuridylic acid is dependent on a labile factor or enzyme, which is present in the ;pH5 fraction' and may be concerned with the formation of new polysomes. Quantitatively the response of the cell-free system to RNA is similar to that of polyuridylic acid, and there appears to be competition between messenger RNA and polyuridylic acid or polyadenylic acid.

Apolipoprotein E polymorphism and coronary heart disease

Apolipoprotein E is a constituent of various lipoproteins and plays an important role in the transport of cholesterol and other lipids among cells of various tissues. The gene is polymorphic with three alleles (epsilon2, epsilon3, and epsilon4) coding for isoforms E2, E3, and E4 and having different binding affinities for the apo E receptors. While the epsilon2 allele is associated with elevated triglyceride levels, epsilon4 allele is associated with increased cholesterol levels. Though several studies support the role of apo E polymorphism in CHD either directly or indirectly via its influence on lipid and lipoprotein levels, there are some studies, which show no association. With the increasing incidence of CHD among Indians, it becomes imperative to identify genetic markers that may predispose individuals to coronary events. It would be of importance to determine if apo E gene will become a usefuladjunct to assess cardiovascular risk profile when performing genetic studies in families.

Methylenetetrahydrofolate reductase gene mutation and hyperhomocysteinemia as a risk factor for coronary heart disease in the Indian population

OBJECTIVE

The screening and therapeutic guidelines for the management of lipid abnormalities are reasonably well established. However, other risk factors like hyperhomocysteinemia (HCA) and single nucleotide polymorphisms involving the angiotensin converting enzyme (ACE) and angiotensinogen genes, various clotting factors etc., have yet to be established firmly as other causative factors of atherothrombotic disease. Our study was aimed at finding the relationship between HCA, folate, vitamins B12 levels, and mutations in the 5,10-methylenetetrahydrofolate reductase (MTHFR) and cystathionine beta-synthase (CBS) genes.

METHODS

We studied 230 subjects, which included patients with angiographically documented coronary heart disease (CHD) (n=115) and controls (n=115) with no history of CHD.

RESULTS

Elevated levels of plasma homocysteine, above 18 nmoles/ml, were detected in 19.13% and 18.26% of our patients and controls, respectively. Homocysteine was significantly correlated to Apo A1 (r=0.51, p < 0.05) and Apo B (r=0.49, p < 0.05). The heterozygous MTHFR mutation was found to be 54.5% (12/22) in our patients with HCA. Of these, 31.8% (7/22) were deficient for plasma folate. Heterozygosity for T833C mutation in the CBS gene was observed in 9.99% (2/22) of our patients with HCA. Both these patients were also deficient for plasma folate and vitamin B12.

CONCLUSION

In our study, heterozygosity for the thermolabile MTHFR mutation was found to be associated with hyperhomocysteinemia (HCA). This genetic predisposition to HCA could be risk factor for CHD and can be correlated with vitamin supplementation. To the best of our knowledge this is the first report from India on plasma homocysteine levels and its genetic aspect in patients with CHD.

Identification of two LDL receptor mutations causing familial hypercholesterolemia in Indian subjects

Familial hypercholesterolemia (FH) is a genetic disorder caused by numerous mutations in the low-density lipoprotein receptor (LDLR) gene. Mutational analyses of Indians in South Africa suggest the possibility of a high frequency of FH in India. This study aimed at identifying mutations in exons 3, 4, 9, and 14 of the LDLR gene among Indians and at eventually developing population-directed molecular-based screening assays. DNA samples from 25 hypercholesterolemic patients with clinical features of FH and 25 normal controls were analyzed for four known point mutations: W66G (exon 3), E207K (exon 4), E387K (exon 9), and P664L (exon 14), which are those most reported among Indian immigrants in South Africa. Subsequently, samples were screened for other mutations by modified heteroduplex analysis in these exons. Point mutations predicted to be common among Indians were absent in the samples analyzed. Heteroduplex analysis and sequencing revealed the presence of novel insertion mutations in two patients. Both mutations are single-nucleotide "G" insertions at position 242 in exon 3 and position 397 in exon 4. The observed mutations are predicted to cause a translational frameshift, encoding truncated LDLR proteins due to premature termination. The mutant proteins are likely to be degraded intracellularly and, therefore, are pathogenic.

Molecular basis of familial hypercholesterolemia: An Indian experience

Familial hypercholesterolemia (FH) is an autosomal dominant disease caused by a multitude of low-density lipoprotein (LDL) receptor gene mutations. The LDL receptor is a cell surface trans-membrane protein that mediates the uptake & lysosomal degradation of plasma LDI., thereby providing cholesterol to cells. Affected individuals have elevated plasma levels of LDL, which causes premature coronary atherosclerosis. FH has an estimated worldwide prevalence of 0.2%. In some subpopulations there is an increased frequency of FH and specific LDL receptor mutations are found to be common due to 'founder gene effect'. Overall, more than 300 naturally occurring LDL receptor mutations have been described. To data upto ten LDL receptor gene mutations have been identified in Indians in South Africa, suggesting increased incidence of FH among Indians. Most mutations have occurred at CpG dinucleotide, a mutational hotspot in human genetic disease. In our study in 25 hypercholesterolemic subjects we have identified two novel insertion mutations in two patients. But the mutations underlying FH are still undefined in the majority of cases. Mutational heterogeneity on the other-hand has complicated disease diagnosis at DNA level. These findings warrant application of a generalized mutation screening method in search for new LDL receptor gene defects.

Changes in the composition of erythrocyte membrane during storage of blood in di-(2-ethyl hexyl) phthalate [DEHP] plasticized poly vinyl chloride (PVC) blood storage bags

Very little information is available on the changes in the erythrocyte membrane composition during storage of blood at 4 degrees C, particularly with respect to the glycosaminoglycans and glycoproteins. In view of this, a detailed study was carried out on the changes in the membrane proteins, glycosaminoglycans (GAG), carbohydrate components of glycoproteins, cholesterol, phospholipids and vitamin E in blood stored in glass bottles and a di-(2-ethyl hexyl) phthalate (DEHP) plasticized PVC bag (Penpol blood bag). Blood was collected in CPDA solution in glass bottles and in Penpol blood bags and kept at 4 +/- 1 degrees C. Analysis was made immediately after blood collection and after 28 and 42 days. Significant increase in the total protein in the erythrocyte membrane was observed during storage of whole blood in glass bottles and Penpol blood bag at 4 degrees C. This increase was progressively more with increase in storage time. Significant changes were also observed in GAG, carbohydrate components of glycoproteins, cholesterol, phospholipids and vitamin E in the erythrocyte membrane under these conditions. The protein:GAG ratio, protein:carbohydrate ratio, cholesterol:phospholipid ratio as well as protein:lipid ratio showed significant increase in the membrane. The extent of these changes was lower in the Penpol bag, indicating the stabilizing effect of DEHP on the erythrocyte membrane.

Clinical trial of benidipine in mild to moderate hypertension

Thirty four patients with mild to moderate hypertension, were put on benidipine 4 mg/day after two weeks of placebo therapy. Twenty five patients completed the trial successfully for 4 mg benidipine. The blood pressure of 20 patients was controlled with benidipine 4 mg/day (effective rate 80%). Five patients with unsatisfactory control on 4 mg/day benidipine were put on 8 mg/day. Four of them were controlled and one was considered as failure (effective rate 80%). Most of the patients tolerated the drug well. Three patients had mild side effects like headache and heaviness in the head. One of them also had puffiness of face and body (on benidipine 8 mg/day) and was withdrawn from the study. One patient had mild constipation. We conclude that benidipine is well tolerated in the dose of 4-8 mg/day and is an effective antihypertensive agent for treatment of patients with mild to moderate hypertension.

Angiotensin converting enzyme gene polymorphism in coronary artery disease: the Indian scenario

Angiotensin converting enzyme is a key component of the renin angiotensin system that plays an important role in cardiovascular regulation. It seems to modulate cardiovascular growth by virtue of its role in the conversion of angiotensin I to angiotensin II and degradation of kinins. A deletion polymorphism localized in intron 16 of the human angiotensin converting enzyme gene, corresponding to a 287 bp long Alu repetitive sequence, was found to be associated with increased risk of myocardial infarction in various subgroups, including European, French and Japanese coronary patients. This angiotensin converting enzyme gene I/D polymorphism was examined by the polymerase chain reaction in a cross-sectional study of 201 healthy Indian subjects and 150 patients (angiographically proven cases of coronary artery disease) whose serum angiotensin converting enzyme levels were concomitantly measured. The D/D, I/D and I/I genotypes were found in 20.66%, 46.66% and 32.66% of the Indian coronary heart disease patients and in 23.38%, 49.75% and 26.86% of controls respectively. One of the reasons for not finding an association between the D allele and coronary artery disease in this study could be the ethnic heterogeneity and disease status heterogeneity among the patients and controls. However the phenotypic variance of serum angiotensin converting enzyme levels is strongly influenced by this polymorphism. In the Indian population, the angiotensin converting enzyme gene I/D polymorphism is not associated with risk for coronary artery disease although it is associated with plasma angiotensin converting enzyme activity. Hence the angiotensin converting enzyme gene I/D polymorphism does not seem to be a useful marker for coronary artery disease in the Indian population.

Synthesis of NAD+ in erythrocytes incubated with nicotinic acid and the effect of di-(2-ethyl hexyl) phthalate (DEHP)

Synthesis of NAD+ from nicotinic acid by erythrocytes incubated in SAGM phosphate solution and effect of di-[2-ethyl hexyl] phthalate, a plasticizer commonly used in PVC blood/component storage bags, on this synthesis was studied. Erythrocytes are able to synthesise NAD+ in SAGM (sodium chloride, adenine, glucose, mannitol) phosphate solution and this synthesis was more in the presence of added nicotinic acid (optimum concentration 1 mM). The level of NAD+ decreased when the incubation period was increased from 24 to 48 hr. Glutamine had a deleterious effect on this synthesis, possibly due to the decrease in pH. Di-[2-ethyl hexyl] phthalate had an inhibitory effect on NAD+ synthesis when the cells were incubated in SAGM phosphate solution, either alone or in the presence of added nicotinic acid. There was significant decrease in the release of potassium and haemoglobin from the cells in the presence of nicotinic acid, indicating increased red cell stability.

Effect of DEHP [di-(2-ethyl hexyl) phthalate] on lipid peroxidation in liver in rats and in primary cultures of rat hepatocytes

The effect of DEHP [di-(2-ethly hexyl) phthalate] on lipid peroxidation in the liver in rats and in primary cultures of rat hepatocytes incubated with it was studied. The doses of DEHP used in this study corresponded to the low levels of this substance leaching into blood stored in DEHP plasticised PVC bags. Increased activity of superoxide dismutase (SOD) and catalase, increased concentration of malondialdehyde (MDA) and conjugated dienes and decrease in the concentration of glutathione and vitamin E have been observed in the liver of rats administered DEHP. Primary cultures of rat hepatocytes incubated with DEHP also showed increase in the activity of these enzymes, increase in the concentration of MDA and decrease in vitamin E. These results indicate that DEHP promotes lipid peroxidation. Incorporation of vitamin E along with DEHP into the culture medium containing hepatocytes counteracted these effects.

Toxic effect of systemic administration of low doses of the plasticizer di-(2-ethyl hexyl) phthalate [DEHP] in rats

DEHP [di-(2 ethyl hexyl) phthalate], a widely used plasticizer in blood storage bags, leaches out in appreciable amounts into blood (about 10 mg/100 ml) resulting in exposure of recipients of blood transfusion to this compound. Various reports indicate the toxicity of DEHP, particularly in liver and reproductive organs but all these studies used large doses (up to 2 g or more/Kg body weight) and oral route of administration which are not relevant to the intravenous administration during blood transfusion or the low amounts present in blood. We have studied changes in the activity of some important enzymes-gamma-GT, ALT, CPK, LDH, alkaline phosphatase, acid phosphatase, beta-glucuronidase and few other parameters like vitamin E, glutathione, serum albumin etc in rats administered low doses of DEHP (corresponding to transfusion of 2, 4, 6 and 10 units of blood). Histopathology of the organs has also been carried out. The results obtained indicate no serious toxic effects for DEHP at the level present in blood stored in DEHP plasticized blood bags as evidenced by the lack of any significant alteration in most of the biochemical parameters studied. Even in those cases where there was alteration (for e.g., decrease in the level of vitamin E) 24 hr after administration of DEHP, it returned to near normal level with in 72 hr to 7 days. No histopathological changes were observed in any of the organs at these levels of DEHP. It is concluded that DEHP did not cause any serious toxic effect even at doses corresponding to transfusion of several units of blood in a recipient.

Free radical generation and the role of allopurinol as a cardioprotective agent during coronary artery bypass grafting surgery

OBJECTIVES

To determine the time course of free radical generation and the role of allopurinol as a cardioprotective agent during coronary artery bypass surgery.

DESIGN

Patients were chosen on a strict 'first come, first chosen' basis, irrespective of their age and sex.

SETTING

Tertiary referral-based hospital and medical research centre.

PATIENTS

A total of 36 patients underwent nonurgent coronary artery bypass grafting surgery. Eighteen patients were treated with allopurinol and 18 patients acted as control.

INTERVENTIONS

Allopurinol 300 mg was administered orally, twice a day for one day preoperatively and a single dose (600 mg) was administered on the morning of the day of the operation.

MEASUREMENTS AND MAIN RESULTS

Lipid peroxidation products were measured by assays for thiobarbituric acid reactive substances, mainly malondialdehyde (MDA). There were no considerable changes in either MDA levels or creatine kinase isoenzyme with muscle and brain subunits (CK-MB) activity during the ischemic period. One minute after release of the cross-clamp the level of MDA was raised significantly (P<0.001). This rise correlated with the severity of ischemia in the group treated with allopurinol as well as the control group (r=0.58, P<0.05 and r=0.49, P<0.05, respectively). The level of MDA and the activity of CK-MB were significantly lower in patients treated with allopurinol (P<0.05 and P<0.001, respectively). The increase in CK-MB activity during reperfusion correlated with aortic cross-clamp time in both the groups (r=0.62, P<0.05 and r=0.69, P<0.05, respectively). Preliminary studies using electron spin resonance spin trapping technique also demonstrated a rise in free radical adducts during reperfusion and this corroborated well with the spectrophotometric method.

CONCLUSION

The results of this study show that, during bypass surgery, there is an increase in lipid peroxidation products and cardiac creatine kinase enzyme at the onset of reperfusion indicating increased free radical activity. It also suggests that pretreatment with allopurinol could effectively attenuate post-ischemic reperfusion injury.

Evidence for free-radical mediated injury during coronary artery bypass surgery

Prolonged global ischemia followed by reperfusion during coronary artery bypass graft (CABG) surgery leads to a burst of oxygen free-radical generation and subsequent myocardial impairment. Blood samples were collected at different time periods from the right atrium of patients (n = 55) who underwent CABG surgery. Free-radical activity was measured by assays for thiobarbituric acid reactive species (TBARS), mainly malondialdehyde (MDA), at zero minute (before aortic cross-clamp), one minute and 10 minutes after declamping i.e. reperfusion. There was a significant increase (p < 0.001) in the level of MDA at one minute of reperfusion which continued to be elevated up to 10 minutes. This increase was significantly correlated with aortic cross-clamp time (r = 0.525, p < 0.05). The activity of CPK and CPK-MB was raised by two fold (p < 0.001) after release of the clamp. Plasma Troponin-T level was estimated in 10 patients during CABG surgery and a significant increase (p < 0.01) was observed at one minute as well as 10 minutes of reperfusion which correlated well (r = 0.81, p < 0.01) with the severity of ischemia. The concomitant rise in TBARS (marker of free-radical activity), CPK, CPK-MB and Troponin-T (indicators of myocardial damage) on reperfusion implies that there is free-radical mediated damage to the cardiac membrane during CABG surgery.

Dyslipidemia in patients with chronic renal failure and in renal transplant patients

Indian studies on lipid profile abnormalities in chronic renal failure (CRF) have varied from no abnormalities at all to significant abnormality (hypertriglyceridemia and reduced HDL) as described in the Western literature. Moreover, there is no Indian study on the effect of renal transplantation on the abnormal lipid profile of CRF. The aim of our study was to determine the lipid profile of CRF patients on conservative treatment, end stage renal disease (ESRD) patients on maintenance hemodialysis (HD) treatment and renal transplant patients. We also looked at the effect of fish oil rich in polyunsaturated fatty acids (Max-EPA) on hypertriglyceridemia of CRF. The study included 4 groups; Gp I: control subjects (n = 9, age = 30 +/- 5 yrs), Gp II: CRF patients on conservative treatment (n = 9, age = 49 +/- 17 yrs), Gp III: ESRD patients on HD for at least 3 months (n = 19, age = 53 +/- 9 yrs), Gp IV: 3 months post-renal transplant patients (n = 9, age 31 +/- 11 yrs). The lipids and lipoproteins analysed include total cholesterol, HDL, LDL, triglycerides, Apo A1 and Apo B. It was observed that in Gp II patients triglycerides were significantly elevated (p < .05) and Apo A1/Apo B significantly abnormally lower (p < .001) compared to Gp I. In Gp IV patients, there was no significant difference in lipid profile compared to Gp I. With the use of Max-EPA in 5 patients with hypertriglyceridemia, there was a significant improvement in hypertriglyceridemia (p < .05). Our study suggests: 1) significant hypertriglyceridemia does develop in a majority of CRF patients. The abnormality probably improves with dialysis treatment and renal transplantation. 2) A lower Apo A1/Apo B ratio in CRF patients may account for higher risk of atherosclerosis. 3) Fish oil rich in polyunsaturated fatty acids improves hypertriglyceridemia of CRF.

A syndrome of osteogenesis imperfecta, optic atrophy, retinopathy and severe developmental delay in two sibs of consanguineous parents

We report on two sibs of consanguineous parents with osteogenesis imperfecta, wormian bones, optic atrophy, retinopathy, fits and severe psychomotor retardation.

Isolation of Legionella pneumophila from patients of respiratory tract disease & environmental samples

In this preliminary study 45 patients suffering from pneumonia were screened for L. pneumophila. Also 17 random environmental samples viz., water from cooling system used for air-conditioning units and samples from respirator-humidifier were screened. Four of 45 (9%) clinical specimens and 13 of 17 (76%) environmental samples showed presence of L. pneumophila. This is the first report from India of the isolation on L. pneumophila.

Bronchoalveolar lavage plasmacytosis in a patient with a plasma cell dyscrasia

A patient with serum monoclonal gammopathy, Bence-Jones proteinuria, and bone marrow plasmacytosis underwent fiberoptic bronchoscopic study for evaluation of interstitial lung disease. Bronchoalveolar lavage fluid contained 47 percent plasma cells, which were monoclonal by immunoperoxidase staining. This is the first time BAL plasmacytosis has been demonstrated in a patient with a plasma cell dyscrasia.

A phase II study of fluorodopan in the treatment of advanced colorectal cancer

In an early phase II study, fluorodopan (5-(2'-fluoroethyl-2'-chloroethyl)-amino-6-methyl uracil) was given to 17 patients with advanced colorectal cancer previously treated with multiple agents. Side effects included mild nausea and vomiting in 14 patients, platelet counts of less than 50,000/microliter in four patients, and wbc counts of less than 2000/microliter in two patients. Partial remission lasting 9 weeks was achieved in one patient, and stable disease with a mean duration of 7.1 weeks was achieved in ten patients. Given in this setting fluorodopan does not appear to have a significant effect in terms of regression of tumor or prolongation of survival.

Reversal of digoxin induced cardiac arrhythmias by nickel chloride

The effect of NiCl2 on digoxin induced cardiac arrhythmias were studied in anesthetized dogs and in isolated perfused hearts of rabbits, guinea pigs and rats. The results indicate that NiCl2 can effectively antagonize the digoxin induced cardiac arrhythmias in both intact as well as in isolated hearts. Sinus rhythm was restored and the cardiovascular status of the animal (which was digitoxic) eventually restored to normal. When not treated with NiCl2 the cardiovascular status of the dogs was progressively worsened leading to death. NiCl2 alone did not have any marked effect in normal hearts. It is likely that Ni2+ might be competing with Ca2+ at the cell membrane sites thereby antagonizing the toxic effects of digoxin. It is also possible that an increase in malic acid and oxaloacetic acid activity induced by NiCl2 may play a role in reversing the toxicity of digoxin.

Comparison of action of beta-methyldigoxin and digoxin utilizing systolic time intervals

The temporal course of orally and parenterally administered beta-methyldigoxin and orally administered digoxin was studied in a series of twenty patients who suffered from congestive heart failure due to a variety of causes. The parameters studied mainly were systolic time intervals. The incontrovertible conclusion was that beta-methyldigoxin acts almost immediately when administered intravenously and after 20 minutes when given by mouth. The peak action, however, by either route of administration was evident at the end of 45 minutes. Viewed in comparison, digoxin after oral administration acted after 2 hours, reaching its peak action after 8 hours. It must be admitted, however, that the magnitude of the response to both drugs, as measured by significant reduction in PEP/LVET ratio and increase in ejection fraction, was the same. Our study suggests that beta-methyldigoxin is as effective an inotropic agent as digoxin, with an additional characteristic of total and rapid gastrointestinal absorption, predictable and rapid onset and much shorter time interval for its peak action.

T-cell chronic lymphocytic leukemia: report of a case and review of the literature

We recently observed a unique case of T-cell type chronic lymphocytic leukemia, documented by cell surface marker analyses. Immunologic tests at the time of diagnosis were as follows: 1) skin tests were negative; 2) in vitro lymphocyte responses to antigens or pokeweed mitogen were absent; 3) in vitro lymphocyte responses to phytohemagglutinin, concanavalin-A or allogeneic cells were low but significant; and 4) stimulating capacity of leukemic T cells were absent. Chromosomal analysis of bone marrow showed a pattern of 45 chromosomes with a marker chromosome. Terminal deoxynucleotidyl transferase activity was very low. Patient responded extremely well to COP (cyclophosphamide-oncovin-prednisone) therapy. Patient died of recurrent transitional cell carcinoma while his leukemia was in complete remission, approximately 20 months after the diagnosis of T-cell CLL.

Neuropathy in tetanus

Thirty-four cases of severe tetanus were studied. On clinical examination weakness and sensory loss compatible with peripheral neuropathy was found in 27. The pattern was usually asymmetrical, the commonest nerves affected being ulnar, median and lateral popliteal, although occasionally circumflex, musculocutaneous, femoral and facial nerves were also involved. Electrophysiological studies showed spontaneous activity resembling denervation potentials, diphasic and positive sharp waves. In some muscles there was also activity resembling spontaneous firing of motor units. Motor and sensory conduction velocities in the affected nerves were moderately reduced and the amplitude of sensory potentials was also reduced. No conduction was found in 11 nerves in 8 patients on initial studies, but 4 out of 7 nerves that could be studied showed rapid recovery. Although most of the nerves in the rest of the patients showed clinical recovery, conduction velocities showed improvement most often when examined about 10 weeks after the onset of trismus. The clinical and electrophysiological evidence suggests the involvement of peripheral nerves in severe tetanus. Serum neuritis, hypersensitivity reaction to tetanus toxoid or drug-induced neuropathy have been ruled out.