EFFECTS OF SPREADING CORTICAL DEPRESSION ON THE INCORPORATION OF [14C]LEUCINE INTO PROTEINS OF RAT BRAIN

Abstract— Incorporation of dl -[1-¹⁴C]leucine into proteins of the cerebral cortex of the rat was measured during spreading cortical depression (CSD) evoked by a single topical application of 25% (w/v) KCI. Maximal inhibition (42 per cent) of the rate of incorporation occurred 1 hr after application of KCI. Spreading depression of 2–3 hr duration was associated with 22 per cent and 13 per cent decreases, respectively, of incorporation of labelled leucine. Specific activity of the free pool leucine was not decreased during CSD but appeared to be higher than controls at 20 min after initiation of CSD. The specific activity of the total free pool amino acids was also increased at 10, 20, 60 and 120 min after application of KCI.
The inhibitory effect of CSD on incorporation of leucine into proteins was uniformly distributed among the crude mitochondrial, microsomal and soluble subcellular fractions from brains of adult animals, while in fractions from 25-day old animals there appeared to be relatively more inhibition in the crude mitochondrial fraction.     

THE CONDITIONS OF RECOVERY OF TRANSMISSIVITY OF NEWLY REPASSIVATED IRON WIRES IN NITRIC ACID

1. Passive steel wires were activated in a bath (Bath A) containing 70 v. per cent HNO₃ (in which they undergo prompt repassivation), and immediately transferred to a second bath (Bath B) containing HNO₃ of a concentration varying in different experiments. After varying intervals in this bath they were transferred while still passive to a third bath (Bath C) containing strong HNO₃ (70 or 100 v. per cent) and there immediately activated. 2. During the immersion in Bath B the wires progressively recover their ability to transmit activation waves in strong HNO₃. The measure of this recovery is the distance travelled by the activation waves in Bath C after the varying times of exposure in Bath B. Transmissivity as thus measured is at first incomplete (decremental) and later becomes complete. The minimal exposures in Bath B required to render wires completely transmissive in the strong acid of Bath C were determined for concentrations of HNO₃ between 10 and 100 v. per cent. With 100 v. per cent HNO₃ in Bath C, these exposures range from 40 minutes or more in 15 v. per cent to 10 minutes in 100 v. per cent HNO₃ (temperature 19–20° in all baths). 3. The time required for complete recovery varies inversely with the concentration of the acid in the recovery bath (Bath B), but increases rapidly with the concentration of the acid in the testing bath (Bath C). Hence at a time when a wire has recovered just sufficiently to transmit non-decrementally in a given strong acid (e.g., 70 v. per cent) it still transmits decrementally in a stronger acid. Complete recovery for transmission in 100 v. per cent HNO₃ requires about twice as long as for 70 v. per cent HNO₃. In HNO₃ of 50 v. per cent and less decremental transmission does not occur. 4. The indications are that recovery is an effect of the progressive solvent action of the external acid on the passivating oxide film, which at its first deposition appears to be relatively thick and hence resistant to electrochemical reduction. The final stage of recovery, when electrical sensitivity and speed of transmission are maximal, would on this hypothesis correspond to minimal thickness, possibly monomolecular. 5. The rate of recovery in Bath B is not far from proportional to the concentration of HNO₃ in the more dilute solutions, but in the higher, especially the strongly passivating, concentrations (70 to 100 v. per cent) the rate becomes appreciably slower than proportional, apparently because of the intense oxidizing action of these solutions, which reinforces the oxide sheet and retards the thinning process. 6. The bearing of these observations on the problem of the conditions of recovery in irritable living tissues (such as nerve) during the absolute and relative refractory periods is briefly discussed.     

Carbon dioxide output and mating in adult cabbage looper moths exposed to discrete light régimes

Carbon dioxide discharge and the number of spermatophores transferred were recorded from populations of adult cabbage loopers, Trichoplusia ni, maintained under various wavelengths and intensities of light. Nocturnal CO₂ output was enhanced by retaining 1 per cent of the diurnal intensity of near-u.v. and blue lights during the scotophase. However, addition of < 10 per cent of the diurnal intensities of u.v., blue, and white lights suppressed CO₂ production. Exposure to gold light resulted in the lowest 24 hr CO₂ accumulations, and red was intermediate. Similarly, maximum levels of mating occurred when cabbage loopers were exposed to nocturnal intensities of 1 per cent of the diurnal u.v., blue, or white lights, even though higher intensities were inhibitory. Considering all nocturnal intensities ranging from 0 to 100 per cent of diurnal levels, u.v. and red yielded the highest mating frequencies, blue and gold were intermediate, and white was lowest. Thus, relatively unique action spectra resulted from each régime.     

INTRAVENOUS ETHER ANESTHESIA

From a study of intravenous ether anesthesia, it was concluded that ether diluted to a 5 per cent solution in 5 per cent dextrose and water may be used to induce and maintain a smooth and easily controlled anesthetic state similar to that obtained with inhalation ether but without the dependence of the latter technique on ventilation. Cough and laryngospasm were absent. Adequate spontaneous respiration can be maintained with this technique. The technique is particularly useful in endoscopy during which the airway is often not available for anesthetic administration.     

Long Acting Single Injection Caudal Anesthesia—1,208 Obstetrical Deliveries with Mepivacaine

Long acting, single injection caudal anesthesia with mepivacaine was studied in 1,208 obstetrical cases.A 1 per cent solution was used in 671 patients and compared with a 1.5 per cent concentration in 537. No remarkable differences were found between the two groups. The 1 per cent solution provided relief of labor discomfort for from 60 to 180 minutes with an average of 110 minutes. In contrast, the 1.5 per cent solution provided an average of 115 minutes with a range of 80 to 210 minutes.A total volume of 30 ml of anesthetic agent yielded anesthesia to a level of the tenth thoracic vertebra or higher in 91 per cent of patients.Significant alterations in blood pressure were uncommon. About 1 per cent of patients required a vasopressor because of a drop in systolic blood pressure below 80 mm of mercury. Another 8 per cent had a drop of over 20 points in systolic pressure but from high enough levels that they did not require a vasopressor.Toxic effects similar to those of lidocaine were found in slightly more than 1 per cent of cases.This anesthesia requires a higher incidence of operative intervention for delivery.     

Respiratory and cardiovascular effects of thyrotropin-releasing hormone as modified by isoflurane, enflurane, pentobarbital and ketamine

Thyrotropin-releasing hormone (TRH) possesses significant arousing and cardio-respiratory stimulant actions. The effects of a 2 mg/kg i.v. bolus dose of TRH on respiration and systemic hemodynamics were compared in conscious, freely-moving rats and during anesthesia with 4 different anesthetics. Fifty-four male Sprague-Dawley rats weighing 285 +/- 4 g (mean +/- S.E.M.) were divided into 5 groups: conscious, enflurane (2%), isoflurane (1.4%), pentobarbital (8 mg/kg/h i.v.), and ketamine (60 mg/kg/h i.v.). Anesthetized rats were intubated and breathed oxygen or anesthetic/oxygen spontaneously. Aortic blood pressure, heart rate, cardiac output, respiratory rate, arterial blood pH, blood gases, lactate and glucose were measured, and data were collected over a 20 min baseline period and for 130 min post-TRH. TRH increased respiratory rate in all groups; concomitant changes in arterial PCO2 indicated increased minute ventilation in the inhalation agent groups but not in the i.v. anesthetic groups or in the awake group. Significant respiratory depression in the enflurane group was rapidly reversed by TRH. The respiratory stimulant and arousing effects of TRH were smallest with ketamine anesthesia. The hemodynamic responses to TRH were consistent with a pattern of sympathoadrenalmedullary activation and were relatively uniform across groups despite anesthetic-induced alterations in baseline values. TRH or its analogues may prove useful as an analeptic in clinical anesthesia.     

AN EVALUATION OF CESAREAN SECTION

The risks of cesarean section have been reduced in step with the increase in safety of all major surgical procedures.In a series of 13,153 deliveries, 1,265 (9.6 per cent) were by cesarean section. There were three obstetrical maternal deaths in 11,888 cases in which delivery was by the vaginal route—0.025 per cent. In the series of 1,265 deliveries by cesarean section there was one death attributable to the operation—0.08 per cent.The total uncorrected fetal loss following cesarean section was 3.8 per cent. This compares favorably with fetal loss of 3.2 per cent in the vaginal delivery group in this series, and with fetal loss rates reported from large obstetrical centers.Anesthesia by spinal injection is the method of choice in cesarean section. There were no maternal deaths or accidents attributable to spinal anesthetic, and in no case was it felt that fetal death was attributable to it.The incidence of maternal morbidity in the cesarean section group following spinal anesthesia was 15.8 per cent—less than half the incidence of morbidity following inhalation anesthesia.     

Chronic hemorrhagic iron deficiency. Sources of hemorrhage, blood loss and systematic iron substitution

In only 121/436 (28 per cent) patients with chronic haemorrhagic iron deficiency bleeding sources could be removed by appropriate management or healed spontaneously. In 61 per cent of all cases the disease lasted from 1 year to greater than 20 years. The fall of haemoglobin per month correlated closely with blood losses per month as calculated by determinations of 59Fe whole body iron loss. Over prolonged periods estimations of the magnitude of blood loss (range 1- greater than 721 per year) based on changes of the iron status under normal diets and under systematic iron substitution. Oral iron administration with appraisable bioavailability was able to compensate blood losses up to 151 and with increasing doses up to 361 per year with maintenance of normal or borderline haemoglobin values. However, side reactions increased considerably after years and with rising doses. Under such circumstances combinations of i.v. iron, oral iron and blood transfusions were successful over prolonged periods.     

MODERN TREATMENT OF PLACENTA PREVIA—A Study of 234 Cases

Study was made of 234 cases of placenta previa occurring in 48,752 deliveries at one hospital during the period 1947-1956. There was no maternal mortality. The uncorrected fetal mortality rate for all weight groups was 21.4 per cent. The rate varied from 88 per cent in babies under 1,500 grams to 5.7 per cent in babies over 2,500 grams. Initial conservative management to permit gestation to continue as close to term as possible is advisable.Ultimate termination of the pregnancy by cesarean section under spinal anesthesia gave the best results. The incidence of transverse and breech presentations in association with placenta previa was inordinately high. A progressive trend toward more conservative treatment of placenta previa was noted in the present series, with a concomitant reduction in fetal mortality rate.     

Modern treatment of placenta previa; a study of 234 cases

Study was made of 234 cases of placenta previa occurring in 48,752 deliveries at one hospital during the period 1947-1956. There was no maternal mortality. The uncorrected fetal mortality rate for all weight groups was 21.4 per cent. The rate varied from 88 per cent in babies under 1,500 grams to 5.7 per cent in babies over 2,500 grams. Initial conservative management to permit gestation to continue as close to term as possible is advisable. Ultimate termination of the pregnancy by cesarean section under spinal anesthesia gave the best results. The incidence of transverse and breech presentations in association with placenta previa was inordinately high. A progressive trend toward more conservative treatment of placenta previa was noted in the present series, with a concomitant reduction in fetal mortality rate.     

Antagonism by ethanol of endotoxin-induced tissue factor activation in relation to the depressed endotoxin binding to monocyte-like U937 cells

Our previous study has reported that ethanol (ETOH) partially inhibited the endotoxin (LPS)-induced tissue factor (TF)-activation in monocytes including blood peripheral monocytes as well as cultured leukemic U937 and THP-1 cells. The present study shows a strong correlation (r=0·92; p<0·01) between TF-activation and depression in LPS binding blocked by ETOH in U937 cells. The antagonism by ETOH of LPS binding was not due to a direct extracellular blockade, since ETOH did not affect the affinity of fluorescein isothiocyanate (FITC)-LPS or -anti CD14 mAb on U937 cells. After U937 cells were treated with 2 per cent (v/v) ETOH for 3 h, LPS binding was however drastically inhibited as shown by immunostaining with FITC-LPS which was viewed on a confocal laser scanning microscope. The results imply that cellular events of the ETOH effect mediate this inhibition of LPS binding. Anti-CD14 mAb (UCHM-1) inhibited LPS binding in a dose-dependent fashion, revealing a competitive specific binding to the LPS receptor. The results suggest that CD14 plays an important role in the recognition of LPS. FITC-UCHM-1 binding was significantly reduced in the cells pretreated with 2 per cent (v/v) ETOH for 3 h, indicating that ETOH modulates the ability to express CD14. CD14 expression was upregulated by priming with LPS which was offset by ETOH. Acetaldehyde, a possible metabolite of ETOH, was tested with no effect on CD14 expression. Taken together, our results show that ETOH downregulates the recognition of LPS, and suggest that the inhibitory action is likely to be mediated by the depression in CD14 expression which was also accompanied by a significantly altered membrane fluidity. Thus, the antagonism by ETOH of the binding of LPS results in a depression in the LPS-induced TF-activation. © 1997 John Wiley & Sons, Ltd.     

Physicians' Use of Relative Value Studies,Report of Bureau of Research and Planning

Data tabulated from the Study of the Characteristics of Physicians in California, conducted by the C.M.A. Bureau of Research and Planning, show that over 70 per cent of all physicians in active private practice utilize the Relative Value Studies, with over 41 per cent stating that they use it “all or most of the time.” Use figures range from almost 78 per cent of physicians who participate in some form of prepayment program to under 53 per cent of physicians who do not participate in any such program.Eighty per cent of all physicians in private practice who use the RVS expressed general satisfaction, with 11.8 per cent dissatisfied and 8.2 per cent stating no opinion as to their satisfaction. Of the 80 per cent who expressed satisfaction, two out of three use the RVS all or most of the time.     

A Large-scale Isolation Procedure for Cereal Mesophyll Protoplasts

A method suitable for the large-scale isolation of cereal protoplastsfrom up to 50 g of leaf material is described. Surface-sterilizedleaves from cultivars of wheat, barley, maize, sorghum, andTriticale were diced and vacuum infiltrated with enzyme mixturecomposed of cellulysin (1 per cent w/v), hemicellulase (1 percent w/v), and macerozyme (0.5 per cent w/v). With this procedure,yields of between 10⁶ to 10⁷ protoplasts per gram of leavescan be reproducibly obtained after only 1.5–3 h of enzymatictreatment. These protoplasts were almost 100 per cent viable(as determined by fluorescein diacetate staining) and incorporationof ³H-uridine and ¹⁴C-leucine into an acid-insoluble fractionwas demonstrated. Almost one-third of the ribosomes of theseisolated protoplasts were present as polysomes. cereals, leaf mesophyll, protoplast isolation     

In Vitro Induction of Haploid, Diploid, and Triploid Androgenic Embryoids and Plantlets in Datura metal L.

Pollen plantlets of Datura metel L. have been successfully rearedin vitro through anther culture on a nutrient medium supplementedwith coconut milk (15 per cent v/v) The early segmentation patternof the proembryos and their subsequent differentiation intoheart, torpedo, and cotyledonary stages were traced. More than100 plantlets were grown to maturity on soil. They grew normallyand produced flowers. Root-tip and leaf-squash preparationsshowed variable numbers of chromosomes in their cells, and thisindicated the occurrence of ploidy plants among the population.Frequency determinations showed the predominant types to bediploid (70 per cent), triploid (24 per cent), and haploid (6per cent). Differences in the morphology of mature plants inregard to floral size, meiotic irregularities in PMCs, formationof giant pollen grains, differential fruitset, somatic mosaicismin respect of chromosome number, and aneuploidy of cells, wererecorded. The origin of diploid and triploid plants is discussed.     

Cardiopulmonary,hematological, serum biochemical and behavioral effects of sevoflurane compared with isoflurane or halothane in spontaneously ventilating goats

This study compares cardiopulmonary, hematological, serum biochemical and behavioral effects of sevoflurane, isoflurane or halothane anesthesia in spontaneously breathing, conventionally medicated goats. Six male adult goats were anesthetized repeatedly at 2-week intervals with three anesthetics. Goats were administered atropine (0.1 mg/kg) intramuscularly, and 10 min later, induced to anesthesia by an intravenous infusion of thiopental (mean 14.3 mg/kg). After intubation, goats were anesthetized with halothane, isoflurane or sevoflurane in oxygen and maintained at surgical depth of anesthesia for 3 h. Recovery from anesthesia with sevoflurane was more rapid than that with isoflurane or halothane. Time-related hypercapnia and acidosis were observed during halothane anesthesia, but not observed during sevoflurane or isoflurane anesthesia. Both hypercapnia and acidosis during sevoflurane anesthesia did not differ from isoflurane anesthesia, but were less during halothane anesthesia, especially at prolonged maintenance period. There were no significant differences between anesthetics in respiration and heart rates, arterial pressures, hematological and serum biochemical values. It was concluded that sevoflurane is an effective inhalant for use in goats showing the most rapid recovery from anesthesia, and that cardiopulmonary effects of sevoflurane are similar to isoflurane than halothane.     

Effect of varying static and changing moisture levels during incubation on extractability of soil phosphate

Summary A sandy loam (pH 6.5) was incubated at 28°C at static moisture levels, ranging from 10 per cent saturation to 133 per cent saturation (waterlogging), for 6 and 12 weeks; other samples covering the same moisture range were first incubated for 6 weeks, and after changing all moisture levels to 50 per cent saturation were incubated for a further 6 weeks.With increasing static soil moisture level during incubation there was a slight reduction in Morgan-extractable phosphate up to 70 per cent saturation, but thereafter, due to anaerobic effects, there were considerable increases in extractable phosphate with increasing moisture level.With changing moisture level during incubation the effects of anaerobiosis became apparent where original moisture level was greater than 50 per cent saturation; extractable phosphate was reduced to levels lower than those occurring where the soil was maintained continuously at 50 per cent saturation. The extent of reduction in extractable phosphate increased with original soil saturation level.     

LOCAL ANESTHESIA IN OPHTHALMOLOGY

With local anesthesia for intraocular operations, postoperative agitation, nausea and vomiting are less frequent, which tends to reduce the number of intraocular complications. Bleeding is less troublesome, and secretions are better controlled. Fewer cardiac and pulmonary complications occur with local anesthesia.Meperidine hydrochloride (Demerol®) and pentobarbital sodium (nembutal) remain drugs of choice in preoperative medication. Lidocaine (Xylocaine®), 1 or 2 per cent, is a most satisfactory local anesthetic for intraocular operations.Complete akinesia of the eyelids has been achieved in every instance by a modified combination of the O''Brien and Van Lint techniques, using lidocaine 1 per cent.Nasolacrimal procedures can be performed satisfactorily by injecting the nasociliary and infraorbital nerves with lidocaine 2 per cent.     

THE CELL IN STARVATION: PHYSIOLOGICAL AND CHEMICAL OBSERVATIONS

Observations made on Amoeba proteus during total inanition revealed the following changes: Dry weight declined progressively, but at a decreasing rate to about 45 per cent of the initial levels when determined in surviving members of a dying population. Protein fell to about 70 per cent of the initial level. A hexane-alcohol extractable component fell during early starvation then rose to about its initial absolute level in the dying cells. While initially most of this component is probably lipide, it is not certain that other materials are not extracted during cell degeneration. Survival as a function of cell size was studied. No advantage in survival was apparent for any size class. Nucleate cell "halves" likewise showed no survival time differential, unlike a highly significant decrease in the survival of enucleate portions. The maintenance of the initial variance about the mean population weight (after hexane-alcohol extraction) during starvation, likewise supports the idea that survival depends largely on concentration parameters.     

Formation of Valine in the Presence of Sodium Acrylate Monomer by Glutamic Acid Producing Bacteria

Glutamic acid producing bacteria accumulated a large amount of valine in the presence of the excess biotin, when sodium acrylate monomer (Na-AM) was added at the earlier phase of culture. Brevibacterium roseum ATCC 13825, particularly, accumulated the large amount of valine among bacteria tested and the conditions of valine accumulation by this strain were investigated.

The most effective addition time of Na-AM was at the earlier phase of logarithmic phase. The optimal concentration of Na-AM for the accumulation of valine was 1.0 per cent (v/v). Most effective nitrogen sources were the combination of 1.0 per cent urea and 0.2 per cent ammonium sulphate. The additions of Mn²⁺ and Fe²⁺ increased valine accumulation. By the excess concentration of biotin for growth, 20 μg/liter or more, did not affected valine accumulation, while the presence of the suboptimal condition of biotin for growth was not good for the formation of valine even in the presence of Na-AM. The accumulation of valine reached 9.0 mg/ml from 75.0 mg/ml of glucose in the presence of 50 μg/liter of biotin and 1.0 per cent (v/v) of Na-AM.

This strain possessed considerable activity of valine formation regardless of the addition of Na-AM and promoted the accumulation of valine by the addition of Na-AM.     

Earlier Diagnosis of Cervical Cancer—An Analysis of Reports to the California Tumor Registry from 1942 to 1963

The mortality rate for cervical cancer in California declined during the period 1950-64. Indirect evidence shows that the incidence is also declining, but it is difficult to assess this decline because of the effect of the increasing use of cytologic examination on incidence rates for cervical cancer.Cervical cancer, in the 57 hospitals reporting to the California Tumor Registry, is being diagnosed at an earlier stage than in previous years. The proportion of cases diagnosed with the lesion still in the in situ stage rose from zero in 1942 to 56 per cent in 1963, and invasive cervical cancer, as a proportion of all invasive cancer in women, decreased from 15 per cent to 9 per cent. There is wide variation among hospitals in the proportion of cervical cancer cases that are in situ at time of diagnosis.