Sugar preferences of "black rats", Rattus rattus L.

The choice of "black rats", Rattus rattus L ., for common sugars - sucrose, jaggery, glucose, fructose and lactose are described. In laboratory colonies, the sugars were preferred in the order glucose > sucrose > jaggery > fructose > lactose; but in another sequence - sucrose > jaggery > glucose > fructose > lactose, in the free living colonies. The discrepancy is accounted for by the characteristics of sugars which influence consummatory behaviour in the two situations.     

Scanning electron microscopy of Fasciola hepatica L. during growth and maturation in the mouse.

Throughout the entire life of the fluke the spines anterior to the ventral sucker are arranged in approximately 60 rings each of 60 to 70 spines. The spines on the posterior body are scattered without any pattern of rings and by 1 week post infection (p.i.) their numbers have doubled (from 3,000 on the newly excysted juvenile) to 6,000 and by 3 weeks p.i. their numbers have multiplied by 8 to 24,000. Just prior to entry into the bile ducts, between 2 and 3 weeks p.i., all spines, anterior and posterior, have metamorphosed from single pointed to multipointed forms by division at the spine tips. Spines on the anterior body of mature flukes recovered from the bile ducts of mice 26 weeks p.i. have between 10 and 15 points whereas those on the posterior body have up to 30 points. The tegument forms a rectangular pattern of plateaux and valleys around each spine on the posterior body of mature flukes but this pattern is not present on the anterior body.     

"Mitochondrial Eve", "Y Chromosome Adam", testosterone, and human evolution.

I suggest primate evolution began as a consequence of increased testosterone in males which increased aggression and sexuality, therefore, reproduction and success. With time, negative effects of excessive testosterone reduced spermatogenesis and started a decline of the group. Approximately 30-40 million years ago, the gene DAZ (Deleted in AZoospermia) appeared on the Y chromosome, increased spermatogenesis, and rescued the early primates from extinction. (Note: DAZ is considered by some to specifically, positively affect spermatogenesis; others suggest it has no effect on spermatogenesis.) Hominid evolution continued with increasing testosterone. The advent of increased testosterone in females of Homo erectus (or Homo ergaster) increased the female-to-male body size ratio, and eventually produced another era of excessive testosterone. Excessive testosterone caused a reduction in population size (bottleneck) that produced the "Mitochondrial Eve" (ME) mechanism. (Only certain females continued during the bottleneck to transmit their mitochondrial DNA.) That is, the ME mechanism culminated, again, in excessive testosterone and reduced spermatogenesis in the hominid line. Approximately 50,000 to 200,000 years ago, a "doubling" of the DAZ gene occurred on the Y chromosome in hominid males which rescued the hominid line with increased spermatogenesis in certain males. This produced the "Y Chromosome Adam" event. The doubling of DAZ allowed further increases in testosterone in hominids that resulted in the increased size and development of the brain. Modern humans periodically fluctuate between the positive and negative consequences of increased levels of testosterone, currently identifiable as the secular trend, increased infections, and reduced spermatogenesis.     

The Transmission of Haemoproteus sp. of English Wood-pigeons by Ornithomyia avicularia

SYNOPSIS. Haemoproteus sp. (probably a subspecies of H., columbae Kruse, 1890) of Columba p. palumbus L. in England produces sporozoites in the salivary glands of Ornithomyia avicularia L. and has been transmitted by the bite of this insect. The parasite has also been isolated from naturallyinfected O. avicularia. Observations on experimentally-infected birds have shown that the macrogametocytes reach their full size in six days, and the microgametocytes in five. The taxonomy of the genus is briefly discussed.     

Nodulisporic acid side-chain modifications: access to the 2", 3", 4", and 6" registers

Efficient routes to access the 2", 3", 4", and 6" registers of the nodulisporic acid (NsA) side chain are disclosed. A mild one-carbon, Ph(2)CdoublebondNCH(2)CtriplebondN mediated homologation of NsA's 3"-aldehyde permitted access to the 4"-register. Curtius reaction of NsA's 3"-acid yielded the corresponding 2"-aldehyde 4 from which the unnatural Delta(2",3")-olefin isomer 2b was obtained. In addition, Arndt-Eistert reactions of the parent NsA permitted a one-carbon homologation to the 6" register. These efforts identified new analogues with significant flea activity and illustrated the biological significance of unsaturation at the 1",2" register.     

Antimicrobial activity of lactic acid bacteria from sour milk products "Narine", "Karine", and "Matsun"

We studied antimicrobial properties of lactic acid bacteria from sour milk products Narine, Karine, and Matsun. The whey of sour milk products included two major fractions of sugars and L-lactic acid and its sodium and calcium salts. Antimicrobial activity of Narine, Karine, and Matsun was related to the presence of L-lactic acid and its sodium and calcium salts.     

Helical order in tarantula thick filaments requires the "closed" conformation of the myosin head

Myosin heads are helically ordered on the thick filament surface in relaxed muscle. In mammalian and avian filaments this helical arrangement is dependent on temperature and it has been suggested that helical order is related to ATP hydrolysis by the heads. To test this hypothesis, we have used electron microscopy and image analysis to study the ability and temperature dependence of analogs of ATP and ADP.Pi to induce helical order in tarantula thick filaments. ATP or analogs were added to rigor myofibrils or purified thick filaments at 22 degrees C and 4 degrees C and the samples negatively stained. The ADP.Pi analogs ADP.AlF4 and ADP.Vi, and the ATP analogs ADP.BeFx, AMPPNP and ATPgammaNH2, all induced helical order in tarantula thick filaments, independent of temperature. In the absence of nucleotide, or in the presence of ADP or the ATP analog, ATPgammaS, there was no helical ordering. According to crystallographic and tryptophan fluorescence studies, all of these analogs, except ATPgammaS and ADP, induce the "closed" conformation of the myosin head (in which the gamma phosphate pocket is closed). We suggest that helical order requires the closed conformation of the myosin head but is not dependent on the hydrolysis of ATP.     

The discrimination of polarized light by the tarantula

Summary The present experiment compared the establishment of a position habit and three subsequent response shifts with and without discriminative stimuli. The discriminative stimuli employed were (a) 90° and 180° polarization patterns and (b) high and low intensity levels. A significant difference (0.05) was found between the running time performance of the polarization discrimination group and the uniform illumination and bright-dark discrimination groups. No similar difference was found with errors as the dependent measure, and no significant between group differences were found during the response shifts. The conclusion was drawn that the extra-ocular hypothesis could not account for the significant difference.This paper is taken from a Master's Thesis submitted to the Florida State University by the senior author, under the direction of the junior author, in partial fulfillment of the requirements for the degree of Master of Science. A portion of this paper was presented at the 1965 meeting of the American Psychological Association.This research was partially supported by a grant from the Florida State University Research Council. The statistical analyses were made possible in part by a National Science Foundation grant (# GP 671) to the Florida State University Computation Center. The authors are indebted to Dr. F. J. King, Institute of Human Learning, Florida State University, for his contribution to the data analysis.     

The effect of small amounts of sodium hypochlorite on the growth of Earl's "L" cells in suspension growth

Of several candidate disinfectants for use in tissue culture work, especially suspension cultures, sodium hypochlorite solution was selected to test its effect on growing cells. Metabolizing cells reduce, sodium hypochlorite oxidizes ; therefore NaOCl leakage into such systems must be neutralized with no untoward effects on the cells. Dilutions of routine disinfectant-grade sodium hypochlorite were tested against cell cultures. Those exposed to 15.62 to 31.25 ppm of NaOCl grew with no apparent cell damage.     

The "Dutch DNA Repair Group", in retrospect

The "Dutch DNA Repair Group" was established about 35 years ago. In this brief historical review some of the crucial decisions are described that have contributed to the relative success of the research of this group. The emphasis of the work of this group has been for many years on the genetic analysis of nucleotide excision repair (NER) and genetic diseases based on defects in this repair process: xeroderma pigmentosum (XP), Cockayne syndrome and trichothiodystrophy.     

Functional and structural roles of critical amino acids within the"N", "P", and "A" domains of the Ca2+ ATPase (SERCA) headpiece

Twenty five amino acids within the "N", "P", and "A" domains of the Ca(2+) ATPase (SERCA1) headpiece were subjected to site directed mutagenesis, taking advantage of a high yield expression system. Functional and conformational effects of mutations were interpreted systematically in the light of the high resolution WT structure, defining direct involvement in catalysis as well as in stabilization of various positions acquired by each domain upon substrate binding and utilization. Amino acids involved in binding of ATP (such as Phe487 and Arg560 in the N domain) or phosphate (such as Asp351, Thr625, Lys684, and Thr353 in the P domain) were characterized with respect to their binding mechanism. Further identified were "positional" roles of several amino acids that stabilize neighboring residues for optimal binding of substrate or Mg(2+), or interface between headpiece domains as they change their relative positions in the course of the catalytic cycle. These include cross-linking of the "N" and "P" domains (e.g., Arg560/Asp627 salt bridge to stabilize domain approximation by ATP binding), and stabilization of the "A", "N", and activated "P" domains in arrangements differing from the ground E2 state and driven by catalytic events. This stabilization is produced through hydrogen bonds at domain interfaces, which vary depending on the intermediate state (e.g., Glu486/T171 in E1P and E2P, as opposed to Glu486/H190 in E2). We demonstrate that specific arrangements of the headpiece domains shown in crystal structures are, in fact, required to trigger displacement of transmembrane segments during the enzyme cycle in solution, allowing long range linkage of catalytic and Ca(2+) binding functions.     

The growth pattern of chimpanzees: Somatic growth and reproductive maturation inPan troglodytes

Growth of chimpanzees reared at the Kumamoto Primates Park of Sanwa Kagaku Kenkyusho Co. Ltd. was studied cross-sectionally from the viewpoints of somatic growth and reproductive maturation. Distance and velocity curves were expressed using spline function method. Males showed adolescent growth acceleration in body weight, with a peak at 7.86 yrs of age, but not in trunk length. Females showed continuous rapid growth from mid-juvenile to adolescent phase in both body weight and trunk length, but no isolated adolescent spurt. The Sanwa chimpanzees matured at about 12.5 yrs of age for females and 15.0 yrs for males. The mean adult weights and trunk lengths were 53.2 kg and 507.8 mm for males and 42.7 kg and 481.6 mm for females. The Sanwa chimpanzees had similar growth patterns to those of the Yerkes chimpanzees, although they showed a slight delay in infancy, and a higher growth rate from the early juvenile phase onwards. Growth patterns in these two laboratories may be regarded as “normative” for laboratory-reared chimpanzees. They matured earlier than wild chimpanzees by more than two years. The major reason for the retarded maturation in wild chimpanzees is the delay of growth from infant to the early juvenile phases (0–4 yrs of age), probably owing to a limited nutritional supply from the mother. Development of the testes comprised three phases: slow growth from infant to juvenile (until 6.4 yrs); rapid growth around adolescence (until 9.2 yrs); and adult (mean testicular volume, 187 cm³). Setting the nutritional standard at 2,000–2,600 Cal/day (= Kcal/day) per adult, calories were considered for captive chimpanzees in each age class.     

Growth and maturation of roker Raja clavata L. in the Solway Firth

Two hundred and seventy-one Raja clavata taken by otter trawl from the Solway Firth were examined for size, sex and state of maturity. Size relationships for both sexes were similar. Total length and disc width were linearly related as were disc width with wing width. Males and females appear to mature at 42 and 45 cm disc width respectively. The Solway population is heavily exploited by an unrestricted commercial fishery and a considerable proportion (48·6%) of the presently retained catch is immature. It is suggested that fishing pressure has brought about a reduction in the size at which female fish mature.     

Growth, maturation and survival of frogs Rana temporaria L.

A total of 1560 breeding frogs were collected in three consecutive years at sites in the west of Ireland. Alt were weighed and measured and the ages of 702 individuals were determined by skeletochronology. The length-weight relationship differed between gravid females, spent females and males, with the gravid females showing the largest weight gain for any increase in length. The majority of males bred for the first time at two years, but most females delayed maturity until they were a year older. While the two-year olds were of similar size, the females subsequently grew at a faster rate and achieved larger maximal sizes than the males. However, both sexes exhibited a decelerating growth rate with age. There was no apparent difference between the sexes in post-maturation survival, which was estimated to be about 50% annually. The oldest frogs were seven years old.