The population characteristics of howler monkeys (Alouatta caraya) in Northern Argentina

Howler monkeys, Alouatta caraya, were collected in family groups from islands in the Rio Parana in northern Argentina. The body weights, lens weights, dental age and reproductive status of 261 individuals illustrated sexually dimorphic body weights after a period of accommodation as young adults, a large proportion of older females (even though there are more young adult males than females) and a higher percentage of pregnancies among these older females. Seventeen families, representing the entire social system of one island, showed that about three quarters were adult (equally divided between the sexes but with fewer older males than females) and the remaining quarter were immature (with an equal sex ratio). Half of the adult females were either pregnant or suckling young. The mean family size is seven which includes peripheral males. Group size and composition as well as adult to immature proportions compared closely with data on A. caraya in the Chaco of Argentina and the 1951 census of A. palliata on Barro Colorado Island. It can be said that when these two species of Alouatta occur in small size families, they have in common: a high proportion of adults to immature, a low proportion of infants, and can have either an equal sex ratio (A. caraya) or preponderance of females (A. palliata).     

Myasthenia Gravis: Anesthetic and Surgical Management of the Patient Undergoing Thymectomy

Experience in the anesthetic and surgical management of 25 patients with myasthenia gravis is recorded. These are subdivided into two groups: those operated on during the period 1950-1958 and those operated on during the period 1959-1964. The purpose of this paper is to indicate improvement in mortality and morbidity due to three major advances: (1) use of the decamethonium diagnostic test in a myasthenia gravis clinic; (2) improvements in assessment and management of respiratory insufficiency; and (3) avoidance of anticholinesterase treatment in the immediate and early postoperative recovery period.Fourteen patients with myasthenia gravis, including five with thymoma and two who were refractory to medication, were in the second (1959-1964) group. There were no deaths and no myasthenic or cholinergic crises. Three prophylactic tracheostomies were performed. No emergency bronchoscopies or tracheostomies were required.     

Single base mutation in the type III procollagen gene that converts the codon for glycine 883 to aspartate in a mild variant of Ehlers-Danlos syndrome IV

Experiments were carried out to test the hypothesis that a 19-year-old proband with a mild variant of Ehlers-Danlos syndrome type IV had a mutation in the gene for type III procollagen. cDNA and genomic DNA were analyzed by using the polymerase chain reaction and cloning of the products into M13 filamentous phage. A mutation was found that converted the codon for glycine 883 of the triple-helical domain in one allele for type III procollagen to a codon for aspartate. The polymerase chain reaction introduced a few artifactual single base substitutions. Also, it was difficult to distinguish copies from the two alleles in many of the M13 clones. Therefore, several different strategies and analyses of about 50,000 nucleotide sequences in a series of clones were used to demonstrate that the mutation in the codon for glycine 883 was the only mutation in coding sequences for the triple-helical domain of type III procollagen that could have contributed to the phenotype. The same mutation in the codon for glycine 883 in one allele for type III procollagen was found in the proband's 52-year-old father who also had a mild variant of Ehlers-Danlos syndrome type IV. The type III procollagen synthesized by the proband's fibroblasts was analyzed by polyacrylamide gel electrophoresis. Less type III procollagen was secreted by the proband's fibroblasts than by control fibroblasts. Also, the thermal stability of the type III procollagen synthesized by the proband's fibroblasts was lower than the thermal stability of normal type III procollagen as assayed by brief protease digestion. The results, therefore, demonstrated that the single base mutation that converted the codon of glycine 883 to a codon for aspartate destabilized the entire triple helix of type III procollagen and probably accounted for the mild phenotype of Ehlers-Danlos syndrome type IV seen in the proband and her father.     

Characterisation of chloride transport at the tonoplast of higher plants using a chloride-sensitive fluorescent probe

The characteristics of Cl^– transport in isolated tonoplast vesicles from red-beet (Beta vulgaris L.) storage tissue have been investigated using the Cl^–-sensitive fluorescent probe, 6-methoxy-1-(3-sulfonatopropyl)-quinolinium (SPQ). The imposition of (inside) positive diffusion potentials, generated with K⁺ and valinomycin, increased the initial rate of Cl^– transport, demonstrating that Cl^– could be electrically driven into the vesicles. Chloride influx was unaffected by SO ₄ ^2- , but was competitively blocked by NO ₃ ^– , indicating that both Cl^– and NO ₃ ^– may be transported by the same porter. In some preparations, increases in free-Ca²⁺ concentration from 10^–8 to 10^–5 mol·dm^–3 caused a significant decrease in Cl^– influx, which may indicate that cytosolic Ca²⁺ concentration has a role in controlling Cl^– fluxes at the tonoplast. However, this effect was only seen in about 50% of membrane preparations and some doubt remains over its physiological significance. A range of compounds known to block anion transport in other systems was tested, and some partially blocked Cl^– transport. However, many of these inhibitors interfered with SPQ fluorescence and so only irreversible effects could be tested. The results are discussed in the context of recent advances made using the patch-clamp technique on isolated vacuoles.Abbreviations and Symbols BTP 1,3-bis[tris(hydroxymethyl)-methylamino]propane - DTT dithiothreitol - EDTA ethylenediaminetetraacetic acid - membrane potential - pH pH gradient - SPQ 6-methoxy-1-(3-sulfonatopropyl)quinolinium - Tricine N-[2-hydroxy-1,1-bis(hydroxymethyl)ethyl] glycine     

Mutation of the Axonal Transport Motor Kinesin Enhances Paralytic and Suppresses Shaker in Drosophila

To investigate the possibility that kinesin transports vesicles bearing proteins essential for ion channel activity, the effects of kinesin (Khc) and ion channel mutations were compared in Drosophila using established tests. Our results show that Khc mutations produce defects and genetic interactions characteristic of paralytic (para) and maleless (mle) mutations that cause reduced expression or function of the alpha-subunit of voltage-gated sodium channels. Like para and mle mutations, Khc mutations cause temperature-sensitive (TS) paralysis. When combined with para or mle mutations, Khc mutations cause synthetic lethality and a synergistic enhancement of TS-paralysis. Furthermore, Khc mutations suppress Shaker and ether-a-go-go mutations that disrupt potassium channel activity. In light of previous physiological tests that show that Khc mutations inhibit compound action potential propagation in segmental nerves, these data indicate that kinesin activity is required for normal inward sodium currents during neuronal action potentials. Tests for phenotypic similarities and genetic interactions between kinesin and sodium/potassium ATPase mutations suggest that impaired kinesin function does not affect the driving force on sodium ions. We hypothesize that a loss of kinesin function inhibits the anterograde axonal transport of vesicles bearing sodium channels.     

Effects of progesterone pretreatment on fertility of gilts mated at an induced pubertal estrus

The effects of progesterone (100 mg/d, im) on pubertal fertility were examined in 247 gilts over 3 experiments. In the first experiment, 128 gilts were exposed to progesterone for 0, 2, 4 or 8 d before receiving PMSG (750 IU) 1 d later. The number of large (>4mm) follicles or corpora lutea (CL) were determined on the day of PMSG injection, Day 0 (onset of estrus), Day 1 or Day 10 (n=8). In the second experiment, embryonic survival was observed in 68 gilts after induction of estrus with PG600 (400 IU PMSG, 200 IU hCG). Vehicle or progesterone was previously administered for 2 d to these gilts, and they were allowed 1, 2, or 3 d between the last progesterone injection and PG600. In Experiment 3, a field trial was conducted in which 51 gilts received vehicle or progesterone for 2 d, followed by a 3-d interval before injection of PG600 to induce estrus. The gilts were allowed to farrow. Treatment with progesterone 1 d before PMSG increased (P<0.05) the number and size of preovulatory follicles and increased (P<0.05) the number of corpora lutea. However, the percentage of gilts pregnant by Day 10, the number of embryos recovered per gilt and embryonic survival were reduced (P<0.05) with progesterone pretreatment. Utilizing a smaller dose of PMSG (750 vs 400 IU) with PG600 negated the effects of progesterone pretreatment on ovulation rate. When the interval between progesterone treatment and PG600 was lengthened to 3 d embryonic survival to Day 30 improved but was similar to that of the vehicle/PG600 treated gilts. Fertility, as defined as conception rate and litter size, was similar between gilts exposed to vehicle or progesterone. These results indicate that pretreatment with progesterone up to the day before PMSG might improve follicular development and ovulation rate at the pubertal estrus with a dose of 750 IU of PMSG but not with the 400 IU (PG600). Reducing the dose of PMSG to 400 IU and allowing for 3 d between progesterone and gonadotropin treatment reduced the incidence of uterine infections but resulted in a fertility rate similar to that of gilts receiving PG600 alone.