A family with a satellited Yq chromosome

Summary A large pedigree with a satellited Yq chromosome is described, Q, C, and NOR banding were performed. Family C proband suffers from a Klinefelter syndrome.     

Patterns of predation in a free-ranging troop of stumptail macaques (Macaca arctoides): Relations to the ecology II

Data on patterns of systematic and ocassional hunting of birds, mammals, reptiles, mollusks and insects by Stumptail macaques are reported for a period of ten months. Systematic hunting of water snails, terrestrial spiders, and land worms was conducted by all age classes, except infants, and both sexes. Of the occasional hunting of birds, large lizards, large frogs, and field mice, the adult females conducted 70%, the adult males 12%, the two year old females 12%, and the two year old males 6%. The differences between males and females were statistically significant (.05 confidence level). Females dominated the hunt and were more interested in meateating than the males. This contrasts strikingly with the data reported for baboons and chimpanzees in which the males dominate the hunt. Of all the prey hunted ocassionally, 76% was shared. The differences between shared and not sared prey were statistically significant (.05 confidence level). All age classes, including infants, participated in meat-sharing. Three types of meat-sharing are described: mother-offspring, hunter-close-friend, and piece-dropping. The prey was shared with genetic relatives, and with close and sistant friends in this order. Pearson’s correlation coeficients between rank of hunter and number of hunts and between rank of hunter and number of individuals with whom the prey was shared yielded +.866 and +.890 respectively. Meat-sharing seems to be similar to that observed for baboons but some differences exist between baboons and chimpanzees on the one hand and Stumptails on the other. Dominance relations in our Stumptails seem to act as the context determining the direction and the type of sharing. An increase in hunting activity during the study period is suggested to be the result of the prey’s migratory and breeding patterns, of environmental changes, and of the high activity scores and physiological states of the adult-females in the troop. Although not hunted, reactions to snakes, iguanas, scorpions, and gulls are also described. This work was supported by grants from Behavioral Sciences Foundation and by NSF Grant No. GB-42235.     

Purification and properties of mammalian toxins from the venom of the Brazilian scorpion Tityus serrulatus Lutz and Mello

The water-soluble part of the dried venom from the scorpion, Tityus serrulatus Lutz and Mello (range, Southeastern Brazil), showed 16 polypeptide bands on polyacrylamide gel electrophoresis. This material exhibited toxic and hyaluronidase activity but no phospholipase, phosphodiesterase, protease, or fibrinolytic activity. Fractionation on glycinamide-treated Sephadex G-50 afforded three protein fractions, which were non-toxic, equitoxic, and three times more toxic than the water-soluble venom. Subsequent separation of the toxic fractions on carboxymethyl-cellulose with phosphate buffers furnished five toxic components, which were further purified on carboxymethyl-cellulose with a salt gradient in acetate buffer. Toxin γ, the major and most basic toxin, is a 62-residue protein that, unlike other scorpion toxins, contains methionine. Automated Edman degradation showed the amino-terminal sequence to be H-Lys-Glu-Gly-Tyr-Leu-Met-Asp-His-Glu-Gly-Cys-Lys-Leu-Ser-Cys-Phe-Ile-Arg-Pro-Ser-Gly-Tyr-Cys-Gly-Arg-Glu-Cys-Gly-Ile-. Toxin γ is the first example of a fifth structural type of mammalian toxin from scorpion venom. Its amino-terminal sequence shows greater homology with toxins similar to Centruroides suffusus suffusus toxin III and Androctonus australis toxin II than with toxins similar to A. australis toxin I or Bhutus occitanus tunetanus toxin I.     

The interaction of phenylglyoxal with soluble and membrane-bound chloroplast coupling factor 1

The rate of inhibition of cyclic photophosphorylation in chloroplast thylakoids by the arginine reagent phenylglyoxal was enhanced in the light, i.e., under conditions where membrane energization occurred. Uncouplers, but not energy-transfer inhibitors, prevented the effect of light. Chemical modification of chloroplast thylakoids by phenylglyoxal under dark or in light conditions affected differently the light-induced exchange of tightly bound ADP. In both cases the exchange was less inhibited than photophosphorylation. Complete inhibition of ATPase activity of soluble CF₁ was correlated with the incorporation of 8 mol [¹⁴C]phenylglyoxal per mol enzyme. About 50% of the incorporated radioactivity was lost at different rates depending on the buffer present and suggesting a change in the stoichiometry of the adduct from 2:1 to 1:1. Inhibition of ATPase and photophosphorylating activities of chloroplasts by modification with [¹⁴C]phenylglyoxal in the dark was associated with the incorporation of 1 and 2 mol reagent per mol membrane-bound CF₁, respectively. In the light the rate of incorporation was enhanced and both reactions were inactivated when 2 mol $\text{[}{}^{14}\text{C]phenylglyoxal}\text{CF}{}_1$ were bound. In all the labelling experiments the radioactivity was mainly recovered from the α- and β-subunits.     

Diethyldithiocarbamate Potentiates the Neurotoxicity of In Vivo l-Methyl-4-Phenyl-1, 2, 3, 6-Tetrahydropyridine and of In Vitro 1-Methyl-4-Phenylpyridinium

Diethyldithiocarbamic acid (DDC) potentiates in vivo neurotoxicity of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and in vitro neurotoxicity of 1-methyl-4-phenylpyridinium (MPP+). Male C57B1/6 mice were given two or five injections of MPTP (30 mg/kg i.p.) preceded 0.5 h by DDC (400 mg/kg i.p.). The mice were tested for catalepsy, akinesia, or motor activity during and after the period of dosing. Striatal and hippocampal tissues were obtained at 2 and 7 days following the last injection and evaluated for dopamine and norepinephrine levels, respectively. These same tissues were also analyzed for the levels of glial fibrillary acidic protein (GFAP), an astrocyte-localized protein known to increase in response to neural injury. Pretreatment with DDC potentiated the effect of MPTP in striatum and resulted in substantially greater dopamine depletion, as well as a more pronounced elevation in GFAP. In hippocampus, the levels of norepinephrine and GFAP were not different from controls in mice receiving only MPTP, but pretreatment with DDC resulted in a sustained depletion of norepinephrine and an elevation of GFAP, suggesting that damage was extended to this brain area by the combined treatment. Mice receiving MPTP preceded by DDC also demonstrated a more profound, but reversible, catalepsy and akinesia compared to those receiving MPTP alone. Systemically administered MPP+ decreased heart norepinephrine, but did not alter the striatal levels of dopamine or GFAP, and pretreatment with DDC did not alter these effects, but did increase lethality. DDC is known to increase brain levels of MPP+ after MPTP, but our data indicate that this is not due to a movement of peripherally generated MPP+ into CNS.(ABSTRACT TRUNCATED AT 250 WORDS)     

Risk sensitivity in starlings: variability in food amount and food delay

Starlings' preferences for constant versus variable food sourceswere studied in the laboratory. The constant alternative gavea fixed amount of food after a fixed delay. The variable alternativeoffered either a varying amount of food after a fixed delay(treatment A) or a fixed amount of food after a variable delay(treatment B). In both treatments the ratio of amount of foodover trial length (the sum of intertrial interval plus delayand handling times) of the constant alternative equaled theaverage of the two ratios of the variable alternative. The variableratios were 30% higher and 30% smaller than the fixed ratio.In free-choice trials (both options available in each trial),the subjects were risk-averse or indifferent in treatment Aand indifferent or riskprone in treatment B. In no-choice trials(only one source available per trial), the latency to respondwas longer in the variable than in the constant source in treatmentA and the opposite in treatment B. The greater preference forvariability in time than for variability in reward amount isnot consistent with either maximizing the ratio of expectedenergy over expected time or the expected ratio of energy overtime for individual trials. There was a negative correlationbetween individual intake rate and degree of risk pronenessfor both kinds of variability. We present a model of choicebased on an information-processing theory for temporal memorythat accounts for the different effects of variability in delayand in amount but cannot explain the effects of intake rate.[Behav Ecol 1991;2:301–308]     

Characterization by photoaffinity labeling of a steroid binding protein in rat liver plasma membrane

Summary The mechanism of steroid uptake by the cell remains controversial. [³H]R5020 was utilized to characterize by photoaffinity labeling the steroid binding site in plasma membrane. This binding was saturable, reversible and had one type of binding site (K _d = 33 ± 4 nm, B _max = 32 ± 2 pmol/mg). [³H]R5020 could be prevented from binding by a variety of steroids (cortisol, progesterone, deoxycorticosterone, and levonorgestrel); estradiol did not have affinity for this binding site. The kinetics of R5020 photoactivation was time dependent and saturable. SDS-PAGE showed a specific band which corresponded to a 53-kDa peptide. The sucrose density gradient analysis has revealed the existence of a protein with a sedimentation coefficient of 3.6 ± 0.2 S. This polypeptide shows different characteristics than cytosolic steroid receptor or serum steroid binding proteins. This binding protein could correspond to the steroid binding site previously found in the plasma membrane.This work was supported by grants PB85-0461 from the Comisión Asesora de Investigatión Científica y Técnica and PGV-8612 from the Departamento de Educatión, Universidades e Investigation del Gobierno Vasco. We thank Roussel-Uclaf (France) for the nonradioactive RU-steroids kindly provided.     

Intraaortic administration of protamine: Method for heparin neutralization after cardiopulmonary bypass

In neutralizing heparin with intravenous protamine sulfate, hypotension may be prevented by administering the drug intraarterially. Forty patients underwent cardiac surgery with extracorporeal circulation in our hospital; each received a rapid injection of nondiluted protamine sulfate in the aortic root to reverse the effects of heparin. To maintain the blood volume at a constant level, volume expanders and inotropic drugs were avoided. The intraaortic injections ranged in duration from 0.2 min to 2.8 min, with a mean of 1.1 min. The mean systolic pressure only dropped from 92 mm Hg (SD +/- 21) before protamine injection to 85 mm Hg (SD +/- 23) after injection (p < 0.0001). In seven patients (18%), no hypotension was evident; in the remaining patients, the systolic pressure returned to preinjection values within a mean of 2.2 min. Coagulation was observed within 3 to 4 min (mean = 2.2 min) after the initiation of injection. This study indicates that intraaortic administration of protamine is a rapid and safe technique for heparin reversal after cardiopulmonary bypass.     

Abundant DNase I-Sensitive Bacterial DNA in Healthy Porcine Lungs and Its Implications for the Lung Microbiome

Human lungs are constantly exposed to bacteria in the environment, yet the prevailing dogma is that healthy lungs are sterile. DNA sequencing-based studies of pulmonary bacterial diversity challenge this notion. However, DNA-based microbial analysis currently fails to distinguish between DNA from live bacteria and that from bacteria that have been killed by lung immune mechanisms, potentially causing overestimation of bacterial abundance and diversity. We investigated whether bacterial DNA recovered from lungs represents live or dead bacteria in bronchoalveolar lavage (BAL) fluid and lung samples in young healthy pigs. Live bacterial DNA was DNase I resistant and became DNase I sensitive upon human antimicrobial-mediated killing in vitro. We determined live and total bacterial DNA loads in porcine BAL fluid and lung tissue by comparing DNase I-treated versus untreated samples. In contrast to the case for BAL fluid, we were unable to culture bacteria from most lung homogenates. Surprisingly, total bacterial DNA was abundant in both BAL fluid and lung homogenates. In BAL fluid, 63% was DNase I sensitive. In 6 out of 11 lung homogenates, all bacterial DNA was DNase I sensitive, suggesting a predominance of dead bacteria; in the remaining homogenates, 94% was DNase I sensitive, and bacterial diversity determined by 16S rRNA gene sequencing was similar in DNase I-treated and untreated samples. Healthy pig lungs are mostly sterile yet contain abundant DNase I-sensitive DNA from inhaled and aspirated bacteria killed by pulmonary host defense mechanisms. This approach and conceptual framework will improve analysis of the lung microbiome in disease.