Fourier transform infrared difference spectroscopy of bacteriorhodopsin and its photoproducts

Fourier transform infrared difference spectroscopy has been used to obtain the vibrational modes in the chromophore and apoprotein that change in intensity or position between light-adapted bacteriorhodopsin and the K and M intermediates in its photocycle and between dark-adapted and light-adapted bacteriorhodopsin. Our infrared measurements provide independent verification of resonance Raman results that in light-adapted bacteriorhodopsin the protein-chromophore linkage is a protonated Schiff base and in the M state the Schiff base is unprotonated. Although we cannot unambiguously identify the Schiff base stretching frequency in the K state, the most likely interpretation of deuterium shifts of the chromophore hydrogen out-of-plane vibrations is that the Schiff base in K is protonated. The intensity of the hydrogen out-of-plane vibrations in the K state compared with the intensities of those in light-adapted and dark-adapted bacteriorhodopsin shows that the conformation of the chromophore in K is considerably distorted. In addition, we find evidence that the conformation of the protein changes during the photocycle.

Electrolyte versus blood cardioplegia: randomized clinical and myocardial ultrastructural study

In 40 consecutive patients undergoing coronary artery bypass, one of two solutions for cardioplegia, each containing 30 mEq/L of K+ was used randomly. The groups were comparable except for intramyocardial temperature. With electrolyte solution (Group A), it was 16.5 degrees +/- 0.34 degrees C, while with blood from the pump-oxygenator (Group B) it was 20.3 degrees +/- 0.41 degrees C (p less than 0.001). After bypass left atrial pressure (LAP) was 11.9 +/- 0.67 torr in Group A and 8.1 +/- 0.49 torr in Group B (p less than 0.001). CPK-MB was elevated in 45% of Group A patients versus 15% in Group B (p less than 0.05). No patient died. Two myocardial infarctions occurred in Group A and one in Group B. Stereological morphometric electron microscopy was performed on biopsy specimens taken from the left ventricle (1) before perfusion, (2) after cardioplegia, and (3) 30 minutes after reperfusion. Group A showed marked intracellular edema, mitochondrial swelling, pronounced depletion of glycogen stores, and focal myofibrillary disorganization. Group B showed near normal myocardial ultrastructure with increased glycogen stores and minimal mitochondrial swelling. Morphometric analysis revealed a statistically significant increase in the degree of mitochondrial swelling (51%) in Group A compared with Group B after reperfusion (p less than 0.001). Thus, blood K+ cardioplegia resulted in better preservation of myocardial ultrastructure, lower ventricular filling pressure, and lesser CPK-MB release compared with this particular electrolyte cardioplegia.

Percutaneous vs surgical placement of intra-aortic balloon assist

Fifty-three patients required IABP over a one-year period. The type of insertion (percutaneous vs surgical) was used randomly. The hemodynamic effect, complication rate, and inability to insert the balloon were similar in both groups. Besides less trauma and cost-effectiveness, the most important advantage of percutaneous over surgical balloon insertion is shorter time interval between decision and insertion which thus allows faster stabilization of ischemic heart patients.

Evaluation of the role of coronary angioplasty in patients with unstable angina pectoris

Seventeen patients presenting with unstable angina pectoris underwent percutaneous transluminal coronary angioplasty (PTCA). Despite vigorous medical therapy, all patients were disabled with 10 experiencing refractory in-hospital angina. PTCA was judged successful in 13 patients and resulted in decreased coronary diameter narrowing from 80 +/- 16% to 34 +/- 13% and reduced transstenotic pressure gradient from 69 +/- 13 to 23 +/- 12 mm Hg. Regional coronary blood flow (CBF) and myocardial metabolism were assessed at rest and during pacing tachycardia in six patients with left anterior descending coronary stenosis. Prior to PTCA, neither regional CBF increased nor coronary vascular resistance declined during rapid pacing; myocardial lactate extraction fell, indicating a shift from aerobic to anerobic metabolism. Following PTCA, however, rapid pacing resulted in increased regional CBF, decreased coronary vascular resistance, and preservation of aerobic metabolism. Following PTCA, successfully dilated patients demonstrated marked relief of angina symptoms, increase in functional capacity, and objective exercise ECG and thallium scintigraphic evidence of relief of previously ischemic myocardium. This investigation demonstrates that PTCA, when combined with medical therapy, can be performed safely and successfully in selected patients who present with otherwise refractory unstable angina, and indicates the procedure deserves further study as a therapeutic alternative in this condition.

Relative effects of hyperbaric oxygen on cations and catecholamine metabolism in rats: protection by lithium against seizures

Analysis of lithium (Li+) in the brain and blood after intraperitoneal injection (i.p.) shows that initially its concentration is high in blood and negligible in the brain. Subsequently its concentration increases in the brain and disappears from the blood. Lithium itself affects neurological actions but the mechanisms remain obscure. It also modifies the toxic action of oxygen at high pressure (OHP), which causes convulsions, either suppressing or exacerbating it. These clearly separate effects correspond with the presence of Li+ in the blood (suppression) or in the brain (exacerbating). Determination of the effect of Li+ and OHP upon cations, catecholamines, ammonia, tyrosine hydroxylase, and monamine oxidase on brain and blood tissue showed that there was very little correspondence between changes in the cations either with Li+ or the toxic effects of OHP. On the other hand, OHP developed a sustained blood and brain hyperammonemia in rats which could be negatively modified by Li+ in the blood. The latter effect also corresponded with a prolongation of convulsive latency. Changes in brain catecholamines, tyrosine hydroxylase, monoamine oxidase and tyrosine were effected by Li+ and potentiated by OHP. These data suggest that Li+ and OHP mediate their effects relatively more through developing hyperammoneic states in both blood and brain than by altering cation concentrations in these tissues.

Restoration of normal coronary hemodynamics and myocardial metabolism after percutaneous transluminal coronary angioplasty

Regional coronary blood flow and myocardial metabolism were evaluated in a patient who underwent percutaneous transluminal coronary angioplasty (PTCA). Angioplasty increased coronary luminal diameter and reduced trans-stenotic gradient. Before PTCA, angina pectoris developed during sustained rapid atrial pacing and was associated with abnormal lactate metabolism and a mild increase in coronary flow and myocardial oxygen consumption. After PTCA, angina was absent during pacing and lactate extraction was preserved. Coronary flow and oxygen consumption were increased to a greater degree than before PTCA. The temporal response of changes in coronary blood flow due to an abrupt increase in heart rate was also evaluated. Floow reached peak value more rapidly after PTCA. These observations suggest that PTCA may result in improved regional coronary blood flow and restoration of normal flow regulatory mechanism and myocardial metabolism.

Genotype dependent radiosensitivity of autotetraploids in Trigonella foenum-graecum L

Different diploids of Trigonella foenum-graecum L. and their corresponding autotetraploids were seed-treated with 40 krad of γ-rays, and parameters such as germination, survival, growth reduction, pollen fertility, pod setting, etc. were recorded. A stimulation of seed germination due to the irradiation could be observed. Contrary to the general rule that polyploids are more radioresistant than their corresponding diploids, one 4x strain was completely killed while the 2x version survived comparatively well. Apparently gene reduplication is not the overall protective mechanism as was once earlier believed. The importance of genotypic influence on radiosensitivity was demonstrated at both the 2x and 4x level. The limitation of interphase chromosome volume and degree of ploidy in predicting radiosensitivity is discussed.

Intrathecal antitetanus serum (horse) with steroid in the treatment of neonatal tetanus

107 patients with neonatal tetanus were studied and the value of intrathecal antitetanus serum with steroid was noted. The mortality rate in a control group (68%) was significantly higher than that of the test group (37%). Furthermore, a delay in antitetanus serum administration was found to have a strong positive linear correlation with the mortality rate. In fact, the mortality rate for neonates who were given antitetanus serum 24 hours after the onset of convulsions was found to be as high as for the control group. This suggests that intrathecal antitetanus serum is ineffective unless it is administered within 24 hours of the onset of convulsions. There was no significant difference in mortality rate whether a dose of 100 units or one of 50 units antitetanus serum was given intrathecally. The mean duration in hospital for survivals of the test group (7.4 days) was significantly shorter than that for survivals of the control group (10.4 days). No complication of intrathecal antitetanus serum was observed during the study.

Effects of hexamethonium and methyl-p-tyrosine on normal rats subjected to convulsions induced by oxygen at high pressure

Hexamethonium infusion (intravenous) does not alter the concentrations of brain catecholamines, ammonia, and amino acids in rats under normal conditions. However, it decreases the concentration of blood adrenaline (A) and nonadrenaline (NA) significantly without affecting blood ammonia and amino acids. Injection of α-methyl-p-tyrosine (α-MPT) (intraperitoneal) decreases brain catecholamines without affecting the concentration of ammonia and amino acids in the brain or catecholamines, ammonia, and amino acids in the blood.In normal, hexamethonium-, and α-MFT-treated rats convulsed by exposure to oxygen at high pressure (OHP), the concentration of ammonia and glutamine plus aspargine increased and glutamate and γ-aminobutyric acid (GABA) (brain only) decreased significantly in both blood and brain. After convulsion, hexamethonium and α-MPT effect the same degree of concentration change for ammonia and amino acids in both blood and brain.When hexamethonium-treated rats are convulsed by OHP, the concentrations of A and NA in blood increased significantly. However, the postconvulsive concentration of A in these rats is significantly less than the preconvulsive control values of normal, undrugged rats. Hexamethonium also prolongs the latency period before convulsions induced by exposure of rats to OHP. This protective action of hexamethonium against oxygen toxicity is probably due to (a) some direct effect of low circulating catecholamines, or (b) delay in the production of toxic levels of ammonia from oxidative deamination of catecholamines, as initial low catecholamine concentration would hinder accumulation of ammonia from such deamination.α-MPT treatment was ineffective in producing an increased latency period before convulsion occurred despite the prevailing low brain catecholamine initially produced by α-MPT treatment. However, the concentration of brain A, NA, and total catecholamines decreased significantly after α-MPT-treated rats were convulsed by OHP exposure. The response of blood catecholamines to OHP-induced convulsions in these α-MPT-treated rats is the same as in normal rats.As α-MPT blocks the synthesis of catecholamines, a further decrease in brain catecholamine values after oxygen-induced convulsions in drugged animals suggests that brain catecholamines are oxidatively deaminated to produce ammonia. These observations suggest that, contrary to earlier reports, brain catecholamines do play an important role in producing ammonia during oxygen toxicity, which, in turn, induces convulsions.

Ovarian activity, and total gonadotrophin and gonadotrophin releasing hormone levels in response to some synthetic non-steroidal ovulating agents in the catfish, Heteropneustes fossilis (Bloch)

Effects of clomiphene citrate, cyclofenil and prostaglandins (PGE1 and PGF2 alpha) on ovarian 32P uptake, on gonadotrophin levels in the pituitary gland and blood serum and on a gonadotrophin releasing hormone-like (GnRH-like) substance in the hypothalamus were investigated in Heteropneustes fossilis. These drugs were very effective in increasing the serum level of gonadotrophin with a subsequent increase in ovarian 32P uptake in sham-hypophysectomized recipients. All the drugs except cyclofenil failed to stimulate 32P incorporation by the ovary in hypophysectomized fish. Clomiphene citrate and cyclofenil also induced a significant increase in the GnRH-like factor in the hypothalamus of H. fossilis. Such a response was not obtained in fish treated with PGE1 and PGF2 alpha. It seems likely that the action of clomiphene is routed through the hypothalamo-pituitary-ovarian axis and that of prostaglandins directly through the pituitary-ovarian axis. The action of cyclofenil is bimodal; one effect like that of clomiphene and the other direct upon the ovary probably by increasing its sensitivity to the available gonadotrophin.

Age-related changes in human thymus

Thymic biopsies obtained during open heart surgery were examined for age-related involution of the parenchyma and changes in cell surface characteristics. In parallel with the parenchymal atrophy, E-rosette-forming cells continuously decreased with age and were progressively replaced by an increasing proportion of 'null' lymphoid cells. These changes appeared to be independent of each other. The significance of these findings in the context of the host's immune mechanism is discussed.

Effect of adrenalectomy on convulsions induced by high-pressure oxygen

Adrenalectomized rats exposed to high pressure oxygen (OHP) until convulsion convulse much later than sham-operated or normal rats. No significant changes in the concentration of noradrenaline (NA) and total catecholamines (TC) in the brain were noted in sham-operated or adrenalectomized rats resulting from sham or real surgery and no change occurred in these variables in normal sham-operated or adrenalectomized animals after OHP leading to convulsion. Brain adrenaline (A) concentration, however, decreased significantly in all three groups following OHP-induced convulsions. Activity of catecholamine O-methyltransferase (COMT) decreased significantly only in adrenalectomized rats. Brain γ-aminobutyric acid (GABA), glutamate, and other amino acid level remained unchanged after adrenalectomy whereas the concentration of ammonia decreased significantly when normal rats were adrenalectomized. After OHP-induced convulsions, the concentrations of brain GABA and glutamate decreased and ammonia and glutamine plus asparagine increased significantly in normal, sham-operated, and adrenalectomized rats. In the blood no significant difference was noted in the concentration of the catecholamines, ammonia, and amino acids either in normal or sham-operated rats. In adrenalectomized rats, the blood A and NA concentrations decreased significantly and tyrosine increased significantly. The concentration of NA, ammonia, and glutamine plus asparagine in rats from all three groups increased after OHP-induced convulsions, whereas the concentration of glutamate decreased significantly. Since the concentration of A increased significantly after convulsions in normal and sham-operated rats but did not change in adrenalectomized rats, it might be proposed that adrenalectomy protects against OHP-induced convulsions by reducing the circulating concentration of A and ammonia.However, these are not the only factors involved in the protection since the sham-operated rats also convulsed much later than normal rats but had similar ammonia and A concentrations to normal animals.

Digitalis in pneumonectomy and its implication

Between 1968 and 1977, 87 patients underwent pneumonectomy at Rhode Island Hospital. Postoperatively, 25 patients developed arrhythmia (29 percent), giving rise to hemodynamic deterioration necessitating aggressive treatment. There were nine hospital deaths (10 percent). The effect of preoperative digitalis was analyzed in 68 patients over age 50 years.In Group 1, digoxin was not used until the onset of arrhythmia. There were 40 patients in this group; 18 developed arrhythmia (45 percent) with four deaths (22 percent).In Group 2, patients were given digitalis preoperatively. There were 28 patients; six developed arrhythmia (21 percent) with no deaths.Thus, the high incidence (45 percent in Group 1 and 21 percent in Group 2), as well as risk of mortality (4/18 patients) from arrhythmia following pneumonectomy, in patients over 50 years of age without digitalization, is a strong indication for preoperative digitalis.

The time course of brain and blood catecholamines, catechol O-methyltransferase, and amino acids in rats convulsed by oxygen at high pressure

The time course of changes in blood and brain catecholamines, catechol O-methyltransferase (COMT), ammonia, and amino acids leading to convulsion by high pressure oxygen breathing (OHP) in rats has been investigated. Brain catecholamines were suppressed by OHP. They changed in phase with brain COMT concentration and consequently were not due to the action of this degrading enzyme. Convulsive actions seem not to be influenced by brain catecholamine concentration. Blood adrenaline concentrations are, however, significantly elevated both prior to and during convulsions. In both brain and blood, ammonia concentration increases, glutamate decreases, and glutamine-aspargine increases. It is proposed that the efficacy of the glutamate-glutamine ammonia buffering system in blood and brain is important in the prevention of the onset of convulsions but that when brain gamma-aminobutyric acid is depressed to critical levels, convulsions result.

Seasonal fluctuation in lipid and cholesterol content of ovary, liver and blood serum in relation to annual sexual cycle in Heteropneustes fossilis (Bloch)

Seasonal fluctuation in lipid content of ovary and liver and cholesterol content of ovary, liver and serum in relation to annual reproductive cycle in H. fossilis has been worked out. Reduction in lipid content of liver was associated with decrease in hepatosomatic index (HSI) in prespawning and spawning phases. But there was an obvious increase in the lipid level of ovary in the above phases which coincided with enhanced gonadosomatic index (GSI) records. Serum and ovary showed a subsidence in their cholesterol contents in prespawning followed by increased level during spawning period. Substraction in liver cholesterol started in prespawning and continued till spawning phase and thereafter regained upward trend. Lipid and cholesterol levels in all organs studied along with GSI and HSI returned to initial values by the end of postspawning stage. Administration of clomid, sexovid, PGE1 and PGF2 alpha for a week did not induce any change in HSI, GSI, lipid and cholesterol values of liver and serum. However, these drugs were effective in suppressing the ovarian cholesterol within a week. The above drugs seem to affect cholesterol level indirectly since they trigger gonadotrophin secretion which in turn probably accelerated cholesterol utilization in ovary for increased steroid hormone output.

Ipsilateral absence of tonsil and microtia with ectopic salivary gland. A case report

This case of congenital unilateral absence of the faucial tonsil and microtia, with atresia of the external auditory canal, and an ectopic salivary gland has not been reported previously; it differs from other congenital abnormalities reported earlier.

Cell studies in prolymphocytic leukaemia

A case of prolymphocytic leukaemia, showing several features not yet reported in this disease, is reported. The majority of lymphocytes in the peripheral blood and bone marrow had markers of both B- and T-lymphocytes. The simultaneous presence of receptors for sheep RBC and surface immunoglobulins on individual cells was demonstrated and the endogenous origin of these markers was established. The lymphocytes had some of the functional characteristics seen in chronic lymphocytic leukaemia (CCL). In vitro cell death in the presence of colchicine (colchicine ultrasensitivity) and polystyrene bead column retention were of the same order as seen in CLL. In contrast with the findings in CLL, these cells were markedly radioresistant in vitro. The dominant clinical features--anaemia and constitutional symptoms--appeared to be related to hypersplenism associated with massive splenomegaly. The relevance of these findings is discussed.

Excitation of surface electromagnetic waves on water

Excitation of surface electromagnetic waves (SEW) on water was studied using optical coupling techniques at microwave frequencies. Excitation of SEW was also achieved using direct horn antenna coupling. The transmitted SEW power was increased by adding acid and salt to water. The horn antenna gave the maximum excitation efficiency 70%. It was increased to 75% by collimating the electromagnetic beam in the vertical direction. Excitation efficiency for the prism (0 degrees pitch angle) and grating couplers were 15.2% and 10.5% respectively. By changing the prism coupler pitch angle to +36 degrees , its excitation efficiency was increased to 82%.

Synthesis of substituted 1-hydroxy-2-naphthanilides as potential cestodicidal agents

A series of substituted 1-hydroxy-2-naphthanilides 4--14 has been synthesized by treating 1-hydroxy-2-naphthoic acids 2 with substituted anilines 3. The nitronaphthanilides, on reduction and subsequent treatment with thiophosgene, gave the corresponding substituted 2-naphthanilide isothiocyanates 30--33. Substitution of the chlorine of 8 by various cyclic amines gave 3'-nitro-4'-substituted 1-hydroxy-2-naphthanilides 15--21. Various 3-aryl-4-oxo-2,3-dihydro-1,3-naphthoxazine-2-thiones 34-43 and 3 aryl-2,4-dioxo-2,3-dihydro-1,3-naphthoxazines 44--51 have been prepared by reacting the corresonding naphthanilides with thiophosgene and ethyl chloroformate, respectively. All the compounds were tested for their cestodicidal activity against Hymenolepis nana infection in rats; 30 was found to be the most active compound of the series, showing 100% clearance of infection at a single oral dose of 7.5 mg/kg.

Measurement of thermoelectric power of solids up to 10 GPa

A method of measuring thermoelectric power of solids as a function of pressure up to nearly 10 GPa is described. A tungsten carbide opposed anvil setup is used to generate the pressure.

A guideline to the management of patent ductus arteriosus in infants and children

Experience with multiple ligation of the patent ductus arteriosus (PDA) at the Hospital for Sick Children, Great Ormond Street, London, is presented. One hundred and sixty-one consecutive cases between January 1971 and December 1974 have been reviewed. Fifty-four children (33%) were less than one year of age. In the majority of cases the diagnosis was made on clinical grounds. Cardiac catheterization and angiography were carried out when associated intracardiac lesions were suspected. The overall mortality was 2.5%. All the deaths occurred in infants less than six months of age who had associated cardiac lesions. There were no deaths in patients who had an uncomplicated PDA or who were more than one year of age. Multiple ligation of the PDA is a simple and safe operation. The risk of operative treatment is affected more by the presence of associated cardiac lesions and the age of the patient than by the surgical technique employed.

Successful correlation of type C complete atrio-ventricular (A-V) canal in infancy

Herein, a successful repair of Type C complete A-V canal in infancy is reported. With a better understanding of anatomy as well as improved perioperative care it appears the primary repair is more reasonable approach than the high risk palliative operation (pulmonary artery banding), when surgery is required in such disease.

Effects of 6-hydroxydopamine on brain and blood catecholamines, ammonia, and amino acids in rats

The effect of 6-hydroxydopamine (6-OHDA) upon brain and blood catecholamines, ammonia, and amino acids has been studied in rats subjected to increasing doses of the drug. Time dependent effects after injection have also been studied. Systemically injected 6-OHDA significantly, acutely reduced brain adrenaline (A), noradrenaline (NA), total catecholamines (TC), gamma-aminobutyric acid (GABA), and glutamic acid (Glu); concomitantly brain ammonia (NH3) increased. In blood, NA and TC were reduced and A and NH3 increased. The changes in brain monoamines are surprising since it has been reported that 6-OHDA does not cross the blood-brain barrier. We have proposed that these changes result from a general stress response or a reflex peripheral sympathetic response to falling blood pressure which in some manner communicates to the central nervous system. As the dose of 6-OHDA increased, brain NH3 increased and Glu decreased. A similar effect was seen from a single dose as the time after injection for sampling brain and blood constituents increased. Blood ammonia increases without change in Glu, glutamine, or asparagine. The source of NH3 may be from deamination of adenine nucleotide or catechols released from nerve terminals under the abnormal stimulus of 6-OHDA.

Effect of 6-hydroxydopamine on brain and blood catecholamine, ammonia, and amino acid metabolism in rats subjected to high pressure oxygen induced convulsions

Effects of 6-hydroxydopamine (6-OHDA) on rat brain and blood adrenaline (A), noradrenaline (NA), ammonia (NH3), gamma-aminobutyric acid (GABA), and amino acid metabolism prior to and after high pressure oxygen (OHP) induced convulsions have been studied. 6-OHDA reduces GABA and glutamate (Glu) rior to OHP exposure in rat brain so that the concentration is even equal to that seen in nondrugged animals after convulsion. Concomitantly, 6-OHDA reduces the latency of OHP-induced convulsion significantly, and increases brain NH3, glutamine, and asparagine significantly. Although 6-OHDA, in increasing dosage, elevates blood A concentration, convulsion produces a significant further increase in A. Blood NA was not significantly changed in drugged, convulsed animals and was much less than blood NA concentrations in nondrugged convulsed animals. Increasing doses of 6-OHDA also increase NH3 in the blood significantly and convulsion increases its concentration further. Latency of convulsion seems to be related to certain monoamine levels since in some drugged animals where A and total catecholamines are still reduced 96 h after the first of two doses of 6-OHDA, NA concentrations are recovered to relatively normal and the convulsion latency time is also increased although it remains significantly abbreviated from undrugged animals' convulsion time. Low brain GABA levels seem to be a prime effector of convulsive activity.

Left ventriculotomy for closure of muscular ventricular septal defects. Treatment of choice

Closure of muscular ventricular septal defects (VSDs) through the right atriotomy or right ventriculotomy may be difficult. These VSDs are often located behind the hypertrophied trabeculae carnae or papillary muscle. Residual or recurrent VSD may result from the difficult approach. Between March 1971 and December 1975, we have used the left ventriculotomy near the apex for closure of muscular VSDs in ten children. The patients' ages ranged from five months to eight years and three months. The diagnosis was established by cardiac catheterisation and left ventricular angiocardiogram in all patients. Six patients had multiple VSDs; in four patients VSD in the muscular septum was present (three apical, one midseptal). Operations were performed on cardiopulmonary bypass with moderate hypothermia and intermittent anoxic arrest. VSDs in the membranous septum were closed through the right atrium. Muscular VSDs were approached through a small vertical incision in the left ventricle near the apex. The postoperative course was uneventful in eight patients. Two patients, aged 16 months and eight years, died; histology showed grade IV pulmonary vascular disease in both. All survivors are well four months to five years after the operation, without clinical evidence of residual or recurrent VSD.

Ovarian 32P uptake in the homoplastic hypophysectomized catfish, Heteropneustes fossilis as an end point for gonadotropin bioassay

Ovarian 32P incorporation in hypophysectomized Heteropneustes fossilis in response to pituitary gland extract pooled from same species and mammalian gonadotropic preparations were studied. Maximum 32P uptake by ovary was obtained when a tracer dose of radiophosphorus was given 30 minutes after LH injection and fish were sacrificed 12 hours after the tracer shot. A log-dose response was observed between ovarian 32P uptake and gonadotropic content of pituitary extract or LH in hypophysectomized H. fossilis. This response was specific because FSH, TSH, prolactin and growth hormone injections failed to induce dose dependent and significant 32P uptake by ovary in similar assay recipients. However, FSH along with LH at higher dosage yielded an additive response. Also a parallelism of log-dose response was obtained between fish pituitary gonadotropin and ovine LH. Index of precision (lambda) was less than 0.214. Since donors and recipients were of the same species this bioassay of 12.5 hours for estimation of total gonadotropic potency seems to be rapid, reliable, sensitive and free from phylogenetic species specificity interaction between hormone and its receptor.

Mustard operation for transposition of the great arteries in a 3-day-old infant, complicated by acute renal failure

A successful operative treatment of a three day old girl with transposition of the great arteries is described. Post-operative course was complicated by furosemide resistant anuria which was treated by peritoneal dialysis. At the age of eight months, she is a pink, active baby, developing normally. This case report demonstrates the importance of aggressive treatment of severe congenital heart lesions in the first few days of life. The importance of post-operative care is emphasized.

Synthesis of 5-chloro-3'-nitro-4'-substituted salicylanilides, a new series of anthelmintic and antimicrobial agents

A number of 5-chloro-3'-nitro-4'-substituted salicylanilides (6--23) have been synthesized by treating 4',5-dichloro-3'-nitrosalicylanilide (5) with various sodium aryl oxides, alkoxides, or amines. These compounds have been tested against Hymenolepis nana infection in rats and have also been evaluated for their in vitro antimicrobial activity against various strains of bacteria and fungi. In the former test 17 was the most active cestodicidal agent showing activity at 30 mg/kg. In the antimicrobial screening, 22 inhibited the growth of all the bacteria and fungi used while 6 was active against the penicillin resistant Staphylococcus aureus at a minimum inhibitory concentration of 0.00609 microgram/mL.

Preoperative intra-aortic balloon assist in high risk revascularization patients

Sixty-five high risk myocardial revascularization patients had preoperative IABP with two operative deaths. Only six patients needed rapid institution of cardiopulmonary bypass after anesthesia induction despite marked blood pressure drop in half the patients. There were only two instances of postpump power failure. Preoperative IABP is a valid method of limiting morbidity associated with coronary surgery in high risk patients.

Respiratory characteristics of a microporous membrane oxygenator

A microporous membrane oxygenator has been used in 258 clinical perfusions for cardiac surgery. In 132 perfusions the oxygenator was ventilated with 100% O2, and in 126 perfusions 98% O2-2%CO2 was used. Patients' BSA was 0.4-2.3 M2. Bypass duration was up to 563 min. In the group ventilated with 100% O2, average PaCO2 was 30 mmHg, with arterial pH of 7.48. 98% O2-2% ventilation resulted in an average PaCO2 of 36 mmHg, with arterial pH of 7.41. CO2 transfer is influenced by gas flow rate, and data from selected cases demonstrate that increasing gas flow results in decreasing PaCO2, while decreasing gas flow increases PaCO2. The thickness of the blood film is decreased by increasing the "shim" pressure, so that increasing the "shim" presure results in higher PaO2. Oxygen saturation averaged 99% for the entire series. Addition of CO2 to the oxygen and appropriate changes in gas flow and "shim" pressure permit changes to be made in the ventilation of the device during perfusion to achieve desired levels of PaO2 and PaCO2 under widely disparate conditions of temperature and flow.

Effect of methallibure on gonadotrophic content, ovarian 32P uptake and gonadosomatic index in the freshwater catfish, Heteropneustes fossilis (Bloch)

Gonadotrophin content in the pituitary gland and blood serum as well as ovarian 32P uptake were studied in response to methallibure treatment in H. fossilis. There was a marked reduction in the gonadotrophic activity of the pituitary gland and blood serum within 3 weeks of methallibure treatment (100 microng/g). A simultaneous significant reduction was also recorded in the ovarian activity of these fish. The fall in ovarian activity caused by methallibure could not be prevented by the administration of LH, FSH or LH+FSH. After cessation of methallibure treatment, LH+FSH (50 microng each) administration restored ovarian activity. It is evident from these results that methallibure alters the secretion of gonadotrophin, and also prevents its action on the ovary.

Preoperative intra-aortic balloon support in surgery for left main coronary stenosis

Twenty-six patients with left main coronary (LMC) stenosis were operated upon with preoperative intra aortic balloon pump (IABP) support. There was no mortality, and no morbidity attributable to the balloon catheter. The most delicate facet of revascularization surgery in this entity is the pre-cardiopulmonary bypass phase including anesthesia induction during which blood pressure fluctuation may further diminish severely compromised coronary flow. Although systolic pressure dropped to below 100 mm Hg in 50% of patients during induction, there were only two patients with electrocardiographic evidence of perioperative myocardial infarction, and only one who needed rantic institution of cardiopulmonary bypass just after induction. Perioperative logistics were quite trouble free in all 26 patients, in marked contrast to 5 LMC patients operated upon prior to our preoperative IABP concent; 3 of these deteriorated upon induction, with two deaths resulting. Preoperative IABP is a reasonable supportive adjunct in surgery for LMC stenosis.

Pulmonary artery banding for truncus arteriosus in the first year of life

Results of pulmonary artery banding (PAB) for truncus arteriosus (TA) in infancy are reviewed in 15 children between 1957 and 1974. There were ten hospital and one late deaths (73%). A policy of early correction of severely symptomatic infants with TA was adopted in 1974. Since October, 1974, four infants with TA and one with hemitruncus had a complete correction. Three of these are surviving 22, 17, and 9 months after the operation. Their weight at operation was 4.7, 6.0, and 3.5 kg.

Left ventricle to pulmonary artery conduit in treatment of transposition of great arteries, restrictive ventricular septal defect, and acquired pulmonary atresia

Progressive cyanosis after banding of the pulmonary artery in infancy occurred in a child with transposition of the great arteries and a ventricular septal defect, and a Blalock-Taussig shunt operation had to be performed. At the time of correction a segment of pulmonary artery between the left ventricle and the band was found to be completely occluded so that continuity between the left ventricle and the pulmonary artery could not be restored. A Rastelli type of operation was not feasible as the ventricular septal defect was sited low in the muscular septum. Therefore, in addition to Mustard's operation, a Dacron conduit was inserted from the left ventricle to the main pulmonary artery to relieve the obstruction. Postoperative cardiac catheterization with angiocardiography indicated a satisfactory haemodynamic result. The patient remains well 11 months after the operation. This operation, a left ventricle to pulmonary artery conduit, may be used as an alternative procedure in patients with transposition of the great arteries, intact interventricular septum, and obstruction to the left ventricular outflow, if the obstruction cannot be adequately relieved.