Anthropological studies in Assam, India. 6. Differentiation processes among Assamese populations

In 1978-79 13 Assamese populations--two Muslim groups, five Mongoloid groups and 6 Hindu caste groups--have been investigated for the distribution of anthropometric, anthroposcopic and dermatoglyphic traits as well as for the distribution of ABO blood groups and PTC taste sensitivity. Except for finger ridge patterns all traits under investigation showed a marked intergroup variability. For anthropometric, anthroposcopic and dermatoglyphic traits a clear differentiation in Mongoloid populations on one hand and Hindu caste groups on the other could be observed and be substantiated by results of corresponding distance analyses. With regard to Muslims it has to be distinguished between Marias who seem to be more closely related to Mongoloid populations and Sheikhs whose phenotypic appearance is more like that of the Hindu caste groups. The results are discussed.     

Anthropological studies in Assam, India. 4. Observations on the Kalitas

Five regional groups of the Kalitas, an Assamese caste group, have been investigated for the distribution of anthropometric and dermatoglyphic traits as well as for the distribution of ABO blood groups and PTC taste sensitivity. The intergroup variability is to some extent considerable. The possible reasons for that are discussed.     

Anthropological studies in Assam, India. 2. Observations on Muslims

Six Muslim groups from various parts of Assam (Goalpara, Kamrup, Darrang, Nowgong, Sibsagar and Dibrugarh) have been analysed for the distribution of anthropometric and dermatoglyphic traits as well as for that of AB0 blood groups and PTC taste sensitivity. The intergroup variability in the distribution of all these anthropological characters is considerable. The possible reasons therefore are discussed.     

Anthropological studies in Assam, India. 1. Observations on five Mongoloid populations

Five Mongoloid population groups from Upper Assam (Ahom, Chutia, Deuri, Mishing and Moran) have been investigated for the distribution of anthropometric and dermatoglyphic traits as well as for that of ABO blood groups and PTC taste sensitivity. The results are discussed with special reference to extent and causes of intergroup variability.     

Meiosis in triploid Lolium. I. Synaptonemal complex formation and chromosome configurations at metaphase I in aneuploid autotriploid L. multiflorum.

A spreading technique for synaptonemal complexes (SCs) was applied to pollen mother cells of two aneuploid genotypes of autotriploid Lolium multiflorum (2n = 3x + 1 = 22). In the earliest nuclei analyzed the axial elements are in six groups of 3 and one group of 4. Most groups have formed multivalents with from one to five pairing partner exchanges, but there are also groups that have formed bivalents and univalents. Some axial elements have formed triple associations, in one case for the length of the trivalent. Unsynapsed axial elements remain aligned with their homologous SCs into pachytene, but this alignment is abolished as these axes pair heterologously among themselves until the entire axial element complement is synapsed. At metaphase I most chromosomes are associated as trivalents and quadrivalents.     

Chemical classification of cattle. 1. Breed groups

From approximately 1000 papers with data on protein polymorphism in some 216 breeds of cattle, 10 polymorphic proteins were compared in means and variances of gene frequencies (arcsin p 1/2) for ten well-recognized breed groups for 196 of the breeds. The polymorphic proteins were alpha-lactalbumin, beta-lactoglobulin, caseins (alpha s1, beta and chi), serum albumin, transferrin, haemoglobin, amylase I and carbonic anhydrase II. The breed groups were North European, Pied Lowland, European Red brachyceros, Channel Island brachyceros, Upland brachyceros, primigenius-brachyceros mixed, primigenius, Indian Zebu, African Humped (with Zebu admixture), and African Humped (Sanga). The coherence within groups and the differences between groups are often impressive. Only carbonic anhydrase II fails to differentiate at least some of the major breed groups. In some cases paradoxical distributions of rare genetic variants can be explained by a more detailed inspection of breed history. The chemical data support the morphological and geographical divisions of cattle into major breed groups. There are three distinct but related brachyceros groups; for some polymorphisms the two Channel Island breeds, the Jersey and the Guernsey, are quite divergent. Although some authorities have considered the Pied Lowland as primigenius, it is a very distinct breed group.     

Chemical classification of cattle. 1. Breed groups

From approximately 1000 papers with data on protein polymorphism in some 216 breeds of cattle, 10 polymorphic proteins were compared in means and variances of gene frequencies (arcsin p½) for ten well-recognized breed groups for 196 of the breeds. The polymorphic proteins were α-lactalbumin, β-lactoglobulin, caseins (α_sl, β and x), serum albumin, transferrin, haemoglobin, amylase I and carbonic anhydrase II. The breed groups were North European, Pied Lowland, European Red brachyceros, Channel Island brachyceros, Upland brachyceros, primigenius-brachyceros mixed, primigenius, Indian Zebu, African Humped (with Zebu admixture), and African Humped (Sanga).
The coherence within groups and the differences between groups are often impressive. Only carbonic anhydrase II fails to differentiate at least some of the major breed groups.
In some cases paradoxical distributions of rare genetic variants can be explained by a more detailed inspection of breed history.
The chemical data support the morphological and geographical divisions of cattle into major breed groups. There are three distinct but related brachyceros groups; for some polymorphisms the two Channel Island breeds, the Jersey and the Guernsey, are quite divergent. Although some authorities have considered the Pied Lowland as primigenius, it is a very distinct breed group.     

White noise analysis of Phycomyces light growth response system. III. Photomutants.

Wiener kernels have been measured for the light growth response of a number of mutants of Phycomyces which show abnormal phototropism (mad mutants). Representative mutants were chosen from the six complementation groups (madA to madF) associated with the light response pathway. One group, madA, associated with the input part of the pathway, exhibits an essentially normal response provided it is tested above its moderate threshold. The groups madB and madC appear more defective, in that their kernel amplitudes are very small even above their thresholds. Their similarity to each other suggests a close functional connection between the respective genes. The remaining three groups (madD, madE, and madF) have all been associated with the output of the pathway. Tbe kernels for all three indicate a gain reduction, which depends gradually on intensity. These three groups appear to have the same absolute threshold as wild-type. None of the mutants studied shows special behavior at high intensity that could be evidence of alterations in the photoreceptor complex.     

Fine structure of ribosomal RNA. II. Distribution of methylated sequences within Xenopus laevis rRNA.

The distribution of methyl groups in rRNA from Xenopus laevis was analyzed by hybridization of rRNA to subfragments of either of two cloned rDNA fragments, X1r11 and X1r12, which together constitute a complete rDNA repeat unit. Using a mixture of 3H-methyl plus 32P-labelled rRNA as probe, the molar yield of methyl groups per rRNA region in hybrid could be calculated. For this calculation the length of the rRNA coding region in each DNA subfragment is needed, which was determined for X1r11 subfragments by the nuclease S1 mapping method of Berk and Sharp. The results show that both in 18S and 28S rRNA the methyl groups are nonrandomly distributed. For 18S rRNA, clustering was found within a 3' terminal fragment of 310 nucleotides. For 28S rRNA, clustering of methyl groups was found within a region of 750 nucleotides in length, which ends 500 nucleotides from the 3' end. In contrast, the 28S rRNA 5' terminal region of 900 nucleotides is clearly undermethylated. The general position of methyl groups in 28S rRNA correlates with the location of evolutionarily conserved sequences in this molecule, as recently determined in our laboratory.     

Free radicals in U.V.-irradiated aqueous solutions of substituted amides: an e.s.r. and spin-trapping study.

The radicals produced by reactions of hydroxyl radicals with alkyl substituted ureas and amides in aqueous solutions have been investigated. Hydroxyl radicals were produced by U.V. photolysis of H2O2 and the short-lived amide and urea radicals were spin-trapped by t-nitrosobutane and identified by e.s.r. For all N-alkyl derivatives of urea and acetamide, and for N,N-dimethyl propionamide and N,N-diethyl formamide, only radicals centred on N-alkyl groups were detected. Radicals situated only on alkyl groups attached to the carbonyl carbon were observed for dimethyl acetamide, trimethyl acetamide and butyramide. However, for N,N-dimethyl butyramide, N, N-diethyl butyramide, N-methyl propionamide and N, N-diethyl propionamide, free radicals were formed which were localized on the alkyl group attached to the amide carbon as well as those attached to nitrogen. The hydrogen atom bound to the carbonyl carbon was abstracted in N-ethyl formamide. Acyl radicals formed by C-N scission due to direct U.V. photolysis of N, N-dimethyl butyramide and N,N-dimethyl propionamide were also detected.     

Selection in Reference to Biological Groups. V. Analysis of Full-Sib Groups

Previous studies in this series have dealt with the consequences of truncation selection operating with respect to random groups within which geno-full-sib group structure. The objective is to compare the results of individual and group selection as these methods operate on populations of random versus typic interaction may exist. The present study deal with a non-random, full-sib groups. In almost all comparisons individual selection is found to be qualitatively and quantitatively superior when used in conjunction with full-sib groups. This is due to the fact that the change in gene frequency for full-sib groups is a function of both direct and associate effects, whereas with random groups it is a function of direct effects only. With regard to group selection the efficiency is invariably superior when selection operates on non-random, full-sib rather than random groups.     

Incompatibility during transplantation of nuclei in amoeba. IV. Transplantation compatibility in different strains of Amoeba proteus]

Seven laboratory Amoeba proteus strains of different origin were tested for their transplantation compatibility (i.e. viability of artificially produced heterokaryons) in all possible pair combinations. Incompatible combinations (14) as well as completely compatible ones (7) were found. Compatibility was distributed among strain combinations non-randomly. All the strains studied could be classified into three groups with respect to compatibility ("compatibility groups") involving 1, 2 and 4 strains, respectively. Within the third group any pair of strains was compatible, as well as both strains of the second group. On the contrary, any strains from different groups were always incompatible. Possible nature of the compatibility groups is discussed. It is suggested that they might be analogous to syngens of Ciliates.     

Genetic studies in relation to Kuru. VI. Evaluation of increased liability to Kuru in Gc Ab-Ab individuals.

The validity of the reported association between GcAb and kuru is analyzed. Phenotypes with one or more GcAb genes have an increased incidence of the disease at the expense of Gc 1-1 and Gc 2-2. Incidence ratios of kuru associated with various phenotypes examined over the linguistic groups studied indicate that only Gc Ab-Ab persons have a significantly greater chance of dying of kuru. The association X2 for the incidence ratio for those phenotypes possessing only one GcAb gene is significant, but there is significant heterogeneity between groups studied. Those of the Gc Ab-Ab phenotype are six times as likely to contract kuru as the baseline group. Criticisms of this analysis include difficulties defining an adequate control group in such heterogeneous populations, errors in determination of Gc phenotypes, inclusion of persons incubating kuru in the control groups, and questions of validity of statistical tests in isolated inbred populations.     

Differential polarization imaging. IV. Images in higher Born approximations.

The theory of differential polarization imaging developed previously within the framework of the first Born approximation is extended to higher Born approximations, taking into account interactions among the polarizable groups in the object. Several properties of differential polarization images, originally described using first Born approximation are modified when higher Born approximations are used. In particular, (a) when the polarizable groups are spherically symmetric, the off-diagonal Mueller elements Mij (i not equal to j) in bright field do not vanish in higher Born approximations, as they do in the first Born approximation case. (b) In higher Born approximations, the dark field Mi4 and M4i (i = 1, 2, 3) images do not vanish as in the first Born approximation, due to the anisotropy induced by the interactions among the groups. (c) When the polarizability tensor of each group is symmetric and real, the bright field M14 and M41 images always vanish in the first Born approximation. In higher Born approximations, these terms do not vanish if the groups bear a chiral relationship to each other. Quantitative criteria for the validity of the first Born approximation in differential polarization imaging are explicitly derived for three different types of media: (a) linearly anisotropic, (b) circularly anisotropic, and (c) linearly and circularly anisotropic (medium displaying linear birefringence and circular birefringence). These criteria define the limits of thickness and the degree of anisotropy of optically thin media. Finally, the possibility to perform optical sectioning in differential polarization imaging in the presence and absence of group interactions is discussed.     

Selective O-phosphitilation with nucleoside phosphoramidite reagents.

In contrast to tetrazole, pyridine hydrochloride/imidazole converts nucleoside phosphoramidites to intermediates that show a high preference for phosphitilating hydroxyl groups relative to nucleoside amino groups. Use of this activating agent and incorporation of a pyridine hydrochloride/aniline wash step in the synthetic cycles permit synthesis of mixed base twenty-mer oligonucleotides from nucleoside reagents containing unprotected amino groups. This approach should be useful for the synthesis of oligonucleotide analogues containing substituents sensitive to reagents used in conventional deblocking steps. Pyridine hydrochloride itself is an effective reagent for activating nucleoside methylphosphonoamidites and ribonucleoside phosphoramidites, as well as deoxyribonucleoside phosphoramidites, when high O/N selectivety is not needed.     

Infrageneric groups in Senecio,S.L., and Cacalia,S.L. (Asteraceae: Senecioneae) in Mexico and Central America

The Mexican and Central American complex of Senecio, s.l., and Cacalia, s.l., is divided into eleven informal groups, with several subgroups, in order to define more or less natural assemblages for detailed revisionary studies. The groups are separated by a key. The discussion accounts for the disposition of the segragate genera recognized by H. Robinson and co-workers, as well as the subgenera employed by Greenman.     

Glutamine active site of formylglycinamide ribonucleotide amidotransferase. 1. Labeling of the enzyme with iodoacetate.

A two-step method for labeling the glutamine active site of formyglycinamide ribonucleotide (FGAR) amidotransferase from chicken liver has been developed in which reaction of all other reactive groups with unlabeled iodoacetate is followed by specific labeling of the glutamine site with radioactive reagent. A study of the reaction as a function of duration, temperature, and pH of the incubation as well as concentration of iodoacetate has revealed that two nonessential groups of the enzyme react in the presence of glutamine and that this modified enzyme is relatively resistant to further carboxymethylation. When this modified enzyme was incubated with radioactive iodoacetate in the presence of FGAR, ATP, and Mg2+ after removal of glutamine by dialysis, about 1 mol of radioactive iodoacetate was incorporated per mol of enzyme with inactivation. This method permits labeling of the active site for glutamine without the use of glutamine analogues.     

Fusobacterium nucleatum subsp. fusiforme subsp. nov. and Fusobacterium nucleatum subsp. animalis subsp. nov. as additional subspecies within Fusobacterium nucleatum.

Using a variety of physiological, biochemical, and molecular systematic analyses, we have shown previously that there are four groups within the species Fusobacterium nucleatum. Two of these groups of strains correspond to the recently proposed taxa F. nucleatum subsp. nucleatum and F. nucleatum subsp. polymorphum. In this paper we show that the two remaining groups are distinct and formally propose that they should be recognized as F. nucleatum subsp. fusiforme (type strain, NCTC 11326) and F. nucleatum subsp. animalis (type strain, NCTC 12276). The tests which we used did not allow a full assessment of the status of F. nucleatum subsp. vincentii compared with F. nucleatum subsp. nucleatum.     

Thermodynamics of barnase unfolding.

The thermodynamics of barnase denaturation has been studied calorimetrically over a broad range of temperature and pH. It is shown that in acidic solutions the heat denaturation of barnase is well approximated by a 2-state transition. The heat denaturation of barnase proceeds with a significant increase of heat capacity, which determines the temperature dependencies of the enthalpy and entropy of its denaturation. The partial specific heat capacity of denatured barnase is very close to that expected for the completely unfolded protein. The specific denaturation enthalpy value extrapolated to 130 degrees C is also close to the value expected for the full unfolding. Therefore, the calorimetrically determined thermodynamic characteristics of barnase denaturation can be considered as characteristics of its complete unfolding and can be correlated with structural features--the number of hydrogen bonds, extent of van der Waals contacts, and the surface areas of polar and nonpolar groups. Using this information and thermodynamic information on transfer of protein groups into water, the contribution of various factors to the stabilization of the native structure of barnase has been estimated. The main contributors to the stabilization of the native state of barnase appear to be intramolecular hydrogen bonds. The contributions of van der Waals interactions between nonpolar groups and those of hydration effects of these groups are not as large if considered separately, but the combination of these 2 factors, known as hydrophobic interactions, is of the same order of magnitude as the contribution of hydrogen bonding.     

Salmonella plasmids of the pre-antibiotic era.

In order to provide a profile of the plasmid gene pool in Salmonella prior to the clinical use of antibiotics, a molecular genetic analysis was made of plasmids in strains collected by E.D.G. Murray between 1917 and 1954. These pre-antibiotic era (PAE) salmonellae contain conjugative plasmids of the same incompatibility groups as contemporary enterobacterial plasmids. Upon analysis of total plasmid content, 42 plasmids, sized between 23 and 72 MDa, were found. We defined and investigated six groups of these PAE Salmonella plasmids in terms of three groups of genes; those involved in plasmid maintenance and incompatibility, DNA repair and virulence. Of the five groups, three were replicon-typed to groups IncI1, IncX and IncFII; one group exhibited no homology to contemporary Inc/Rep probes, and one group represented virulence plasmids containing a common plasmid-partitioning locus. The results indicated that most of the PAE groups were progenitors of contemporary R-plasmids, except for the virulence plasmids, which have generally not evolved as vectors of antibiotic resistance.