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1.
C S Chung J D Niswander D W Runck S E Bilben M C Kau 《American journal of physical anthropology》1972,36(3):427-433
Racial comparisons of prevalences of dental anomalies were made on 13,473 Hawaiian-born children aged 12 to 18 years. Dental anomalies studied included supernumerary teeth, peg-shaped lateral incisors, dens in dente (invaginated tooth), hypoplasia, fusion (or gemination), and high cingulum of upper lateral incisors (barrel-shaped teeth) in the permanent dentition. The highest frequency of peg-shaped laterals was observed among Filipinos and part-Filipinos with no evidence of heterogeneity among other racial groups. Dens in dente was more common among Hawaiian descendents. Fusion or gemination was observed more commonly among children with Chinese parentage. High cingulum of laterals was fairly common in Orientals particularly in Filipinos and nil among Caucasians and Hawaiians. There was neither significant maternal effect nor effect (non-additive) of hybridity. 相似文献
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Tall and short Amazonian caatinga at La Esmeralda (rainfall 2600 mm yr–1) are described and compared with those at San Carlos de Río Negro (3600 mm yr-1). The tall forests have much in common: thin-boled trees, many with scleromorphic mesophylls, lack of thick-stemmed climbers and of herbs, species paucity in all life-forms, domination by Eperua, and a high proportion of Bombacaceae, Clusiaceae and Euphorbiaceae. The short caatingas are also structurally and floristically similar but at La Esmeralda the notophyll scrubland species are lacking. At La Esmeralda, the common tree species are autochorous, but the majority of plants (particularly understorey species) are zoochorous. Relatively high transmission of light to the floor of the tall caatinga (1.5% PAR) may explain how trees with light-demanding architecture regenerate in the understorey. The presence of Cecropia and weedy species in the caatinga only at San Carlos may be the result of greater human interference there. The soils at San Carlos and La Esmeralda are similar: thick humus overlying bleached sand, waterlogged most of the year. The water table at La Esmeralda drops to >1 m depth during the drier months, but tensiometers at 30 cm depth did not indicate significant water shortage. Soils are consistently wetter in the short caatinga than the tall. Shortage of nitrogen appears to determine the major structural and physiognomic features of the caatinga, and depth of aerated soil appears to determine its stature. Comparisons are made between tall caatinga, wallaba and swamp forest in the Guianas and heath forests of Malaysia.Abbreviations PRF
Palm-Rich Forest
- SC
Short Caatinga
- TC
Tall Caatinga 相似文献
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Govindan Selvakumar Muthugounder Mohan Satya N. Sushil Samaresh Kundu Jagadish C. Bhatt Hari S. Gupta 《Biocontrol Science and Technology》2007,17(5):525-534
White grubs (Coleoptera: Scarabaeidae) are cosmopolitan and polyphagous insect pests of agricultural crops, forests and pastures around the world. The lack of an environmentally sound approach for white grub management has prompted the exploration and detection of a novel microbial biocontrol agent against these sub-terranean insect pests. In this study we describe the isolation, establishment of pathogenesis, biochemical characterization and phylogenetic analysis of an entomopathogenic Bacillus cereus strain WGPSB-2 (MTCC 7182), isolated from an atrophied pupa of Anomala dimidiata, collected from the N.W. Indian Himalayas. The sequencing and subsequent comparison of the 16S rDNA revealed that the strain has100% similarity with Bacillus cereus sequences. Phylogenetic analysis of the 16S rDNA sequence revealed that the isolate is closely related to Bacillus thuringiensis and Bacillus sphaericus. In vitro bioassays showed that the isolate was able to infect and cause 92 and 67% mortality in second instar larvae of Anomala dimidiata and Holotrichia seticollis, respectively. The infected larvae exhibited bacterial septicemia like symptoms and mortality occurred between the third and ninth weeks after inoculation. The culture has been granted the accession number MTCC 7182 by the Microbial Type Culture Collection and Gene Bank, Institute of Microbial Technology, Chandigarh, India. 相似文献
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While ion pairs are readily identified in crystal structures, longer range electrostatic interactions cannot be identified from the three-dimensional structure alone. These interactions are likely to be important in large, multisubunit proteins that are regulated by allosteric interactions. In this paper, we show that these interactions are readily detected by electrostatic modeling, using, as an example, unliganded Escherichia coli aspartate transcarbamylase, a widely studied allosteric enzyme with 12 subunits and a molecular weight of 310 kD. The Born, dipolar, and site-site interaction terms of the free energy of protonation of the 810 titratable sites in the holoenzyme were calculated using the multigrid solution of the nonlinear Poisson-Boltzmann equation. Calculated titration curves are in good agreement with experimental titration curves, and the structural asymmetry observed in the crystal structure is readily apparent in the calculated free energies and pK1/2 values. Most of the residues with pK1/2 values that differ substantially from those of model compounds are buried in the low dielectric medium of the protein, particularly at the intersubunit interfaces. The dependence of the site-site interaction free energies on distance is complex, with a steep dependence at distances less than 5 Å and a more shallow dependence at longer distances. Interactions over distances of 6 to 15 Å require a bridging residue and are often not apparent in the structure. The network of interactions between ionizable groups extends across and between subunits and provides a potential mechanism for transmitting long-range structural effects and allosteric signals. © 1996 Wiley-Liss, Inc. 相似文献
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Asao Makioka Masahiro Kumagai Kazushi Hiranuka Seiki Kobayashi Tsutomu Takeuchi 《Experimental parasitology》2011,(1):195-201
The differentiation processes of excystation and encystation of Entamoeba are essential for infection and completion of their life-cycle, and the processes need cell motility and its control by actin cytoskeletal reorganization. This study investigated actin depolymerizing factor (ADF)/cofilin (Cfl) family proteins, which are important molecules in actin cytoskeletal reorganization, in Entamoeba invadens in relation to the encystation and excystation. Axenic culture systems were used to induce encystation and excystation. A homology search of the E. invadens genome database and molecular cloning identified three ADF/Cfl family proteins of the parasite (named for short as EiCfl-1, EiCfl-2, and EiCfl-3). This is different from other Entamoeba species, i.e. Entamoeba histolytica and Entamoeba dispar, each of which has only one ADF/Cfl family protein. These ADF/Cfl of E. invadens do not have Ser3 (serine locates third from first methionine), similar to E. histolytica, E. dispar, Saccharomyces cerevisiae and Schizosaccharomyces pombe, although the activity of ADF/Cfl is negatively regulated by phosphorylation of the Ser3 in metazoans. Phylogenetic analysis revealed that Entamoeba Cfl formed a distinctive clade that is separate from other organisms, and the branches of the tree were separated in two consistent with the presence and absence of Ser3. Rabbit anti-EiCfl-2 serum reacted with all recombinant EiCfls and EiCfl in lysates of cysts, trophozoites and metacystic amoebae. Immunofluorescence staining with this antiserum showed co-localization of EiCfl with actin beneath the cell membrane through the life stages. Both proteins proved to be rich in pseudopodia of trophozoites and metacystic amoebae. Real-time RT-PCR showed that mRNAs of EiCfl-2 and actins were highly expressed, but there were few mRNA of EiCfl-1 and EiCfl-3. Remarkably decreased mRNA levels were observed in EiCfl-2 and actins during encystation. All three EiCfls and actins became transcribed after the induction of excystation. The mRNAs of only EiCfl-1 and EiCfl-3 increased remarkably when the excystation was induced in the presence of cytochalasin D. These findings demonstrate that EiCfl-2 and actins co-localize beneath the cell membrane in trophozoites and cysts as well as metacystic amoebae being rich in pseudopodia, that EiCfl-1 and EiCfl-3 are expressed only after the induction of excystation, and that enhanced excystation by cytochalasin D is associated with high expression of EiCfl-1 and EiCfl-3. 相似文献
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Identification of keratins and analysis of their expression in carp and goldfish: comparison with the zebrafish and trout keratin catalog 总被引:1,自引:0,他引:1
García DM Bauer H Dietz T Schubert T Markl J Schaffeld M 《Cell and tissue research》2005,322(2):245-256
With more than 50 genes in human, keratins make up a large gene family, but the evolutionary pressure leading to their diversity
remains largely unclear. Nevertheless, this diversity offers a means to examine the evolutionary relationships among organisms
that express keratins. Here, we report the analysis of keratins expressed in two cyprinid fishes, goldfish and carp, by two-dimensional
polyacrylamide gel electrophoresis, complementary keratin blot binding assay, and immunoblotting. We further explore the expression
of keratins by immunofluorescence microscopy. Comparison is made with the keratin expression and catalogs of zebrafish and
rainbow trout. The keratins among these fishes exhibit a similar range of molecular weights and isoelectric points, with a
similar overall pattern on two-dimensional gels. In addition, immunofluorescence microscopy studies of goldfish and carp tissues
have revealed the expression of keratins in both epithelial and mesenchymally derived tissues, as reported previously for
zebrafish and trout. We conclude that keratin expression is qualitatively similar among these fishes, with goldfish and carp
patterns being more similar to each other than to zebrafish, and the cyprinid fishes being more similar to each other than
to the salmonid trout. Because of the detected similarity of keratin expression among the cyprinid fishes, we propose that,
for certain experiments, they are interchangeable. Although the zebrafish distinguishes itself as being a developmental and
genetic/genomic model organism, we have found that the goldfish, in particular, is a more suitable model for both biochemical
and histological studies of the cytoskeleton, especially since goldfish cytoskeletal preparations seem to be more resistant
to degradation than those from carp or zebrafish.
This work was supported by grants to J.M. from the Stiftung Rheinland Pfalz für Innovation (836-386261/138) and the Deutsche
Forschungsgemeinschaft (Ma 843/5-1) and a grant to D.G. from the National Science Foundation (INT-0078261). 相似文献
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Mohammad Hossein Hedayati Dariush Norouzian Mahdi Aminian Shahram Teimourian Reza Ahangari Cohan 《Preparative biochemistry & biotechnology》2017,47(10):990-997
Background: Oxidative degradation of human recombinant erythropoietin (hrEPO) may occur in manufacturing process or therapeutic applications. This unfavorable alteration may render EPO inefficient or inactive. We investigated the effect of methionine/54 oxidative changes on the amino acid sequences, glycoform distribution and biological activity of hrEPO. Methods: Mass spectrometry was applied to verify the sequence and determine the methionine oxidation level of hrEPO. Isoform distribution was studied by capillary zone electrophoresis method. In vivo normocythemic mice assay was used to assess the biological activity of three different batches (A, B, and C) of the proteins. Results: Nano-LC/ESI/MS/MS data analyses confirmed the amino acid sequences of all samples. The calculated area percent of three isoforms (2–4 of the 8 obtained isoforms) were decreased in samples of C, B, and A with 27.3, 16.7, and 6.8% of oxidation, respectively. Specific activities were estimated as 53671.54, 95826.47, and 112994.93?mg/mL for the samples of A, B, and C, respectively. Conclusion: The observed decrease in hrEPO biological activity, caused by increasing methionine oxidation levels, was rather independent of its amino acid structure and mainly associated with the higher contents of acidic isoforms. 相似文献
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Charlotte E. Mardle Layla R. Goddard Bailei C. Spelman Helen S. Atkins Louise E. Butt Paul A. Cox Darren M. Gowers Helen A. Vincent Anastasia J. Callaghan 《Biochemistry and Biophysics Reports》2020
Increasing resistance of bacteria to antibiotics is a serious global challenge and there is a need to unlock the potential of novel antibacterial targets. One such target is the essential prokaryotic endoribonuclease RNase E. Using a combination of in silico high-throughput screening and in vitro validation we have identified three novel small molecule inhibitors of RNase E that are active against RNase E from Escherichia coli, Francisella tularensis and Acinetobacter baumannii. Two of the inhibitors are non-natural small molecules that could be suitable as lead compounds for the development of broad-spectrum antibiotics targeting RNase E. The third small molecule inhibitor is glucosamine-6-phosphate, a precursor of bacterial cell envelope peptidoglycans and lipopolysaccharides, hinting at a novel metabolite-mediated mechanism of regulation of RNase E. 相似文献
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For a successful completion of a movement task the motor control system has to observe a multitude of internal constraints that govern the coordination of its segments. The purpose of this study was to apply principal component (PC) analysis to detect differences in the segmental coordination between healthy subjects and patients with medial knee osteoarthritis (OA). It was hypothesized that (1) systematic differences in patterns of whole body movement would be identifiable with this method even in small sample sized groups and that (2) these differences will include compensatory movements in the OA patients in both the lower and upper body segments. Marker positions and ground reaction forces of three gait trials of 5 healthy and 5 OA participants with full body marker sets were analyzed using a principal component analysis. Group differences in the PC-scores were determined for the first 10 PC-vectors and a linear combination of those PC-vectors where differences were found defined a discriminant vector. Projecting the original trials onto this discriminant vector yielded significant group differences (t(d=8)=3.011; p=0.017) with greater upper body movement in patients with knee OA that was correlated with the medial–lateral ground reaction force. These results help to characterize the adaptation of whole-body gait patterns to knee OA in a relatively small population and may provide an improved basis for the development of interventions to modify knee load. The PC-based motion analysis offered a highly sensitive approach to identify characteristic whole body patterns of movement associated with pathological gait. 相似文献
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Paola Barboro Erica Repaci Paola Orecchia Eligio Patrone 《Experimental cell research》2009,315(2):226-1479
Tumor progression is characterized by definite changes in the protein composition of the nuclear matrix (NM). The interactions of chromatin with the NM occur via specific DNA sequences called MARs (matrix attachment regions). In the present study, we applied a proteomic approach along with a Southwestern assay to detect both differentially expressed and MAR-binding NM proteins, in persistent hepatocyte nodules (PHN) in respect with normal hepatocytes (NH). In PHN, the NM undergoes changes both in morphology and in protein composition. We detected over 500 protein spots in each two dimensional map and 44 spots were identified. Twenty-three proteins were differentially expressed; among these, 15 spots were under-expressed and 8 spots were over-expressed in PHN compared to NH. These changes were synchronous with several modifications in both NM morphology and the ability of NM proteins to bind nuclear RNA and/or DNA containing MARs sequences. In PHN, we observed a general decrease in the expression of the basic proteins that bound nuclear RNA and the over-expression of two species of Mw 135 kDa and 81 kDa and pI 6.7-7.0 and 6.2-7.4, respectively, which exclusively bind to MARs. These results suggest that the deregulated expression of these species might be related to large-scale chromatin reorganization observed in the process of carcinogenesis by modulating the interaction between MARs and the scaffold structure. 相似文献
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《Journal of Genetic Engineering and Biotechnology》2014,12(1):27-35
178 bacterial strains were isolated from the soil samples collected from different regions of India out of which, 20 bacterial isolates were selected for alkaline protease production. The alkaline protease production efficiency of organisms was monitored at regular intervals (24 h) upto 7 days at 37 °C, pH 10. The 16S rDNA sequencing and RAPD-PCR based technique were used to identify the genetic variability among the 20 isolates of alkaline protease producing bacteria. The phylogenetic analysis indicated that the isolates can be separated into two clusters which could be further subdivided into five groups. Group 1 and 5 represented the family Bacillaceae, Groups 2 represented the Micrococcaceae family while Group 3 included the Arthrobacter bacterial group (family Micrococcaceae) from different geographical locations, respectively. Group 4 was identified as Pseudomonadaceae which was gram (−) bacteria. 21 different oligonucleotide primers were used to amplify approximately 261 fragments from each DNA sample. The bands were scored on the basis of their presence and absence and similarity between DNA samples was checked using Jaccard’s coefficient. Isolates were distinguished into distinct groups based on RAPD profiles from different geographical locations, morphological features and enzyme production efficiency. For cluster analysis the dendrogram was constructed using the unweighted pair group method with arithmetic averages (UPGMA). The results indicated that 16S rDNA and RAPD-PCR are suitable methods for rapid identification and differentiation of alkaline protease producing bacteria. 相似文献
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Mark A. Kay J. -Y. Zhang Marcelo Jacobs-Lorena 《Molecular & general genetics : MGG》1988,213(2-3):354-358
Summary
Minute loci represent a class of about 50 different Drosophila genes that appear to be functionally related. These genes may code for components of the protein synthetic apparatus. While one Minute locus has been recently shown to code for a ribosomal protein, it is not yet known whether any of the other Minute loci also code for ribosomal proteins. We have addressed this question by a combined molecular and genetic approach. In this report, a cloned DNA encoding the ribosomal protein rp21 is partially characterized. The rp21 gene maps to the same region (region 80 of chromosome 3L) as the temperature-sensitive Minute QIII gene. Using P-element mediated transformation, the rp21 gene was transformed into the germline of Drosophila. RNA blot experiments revealed that the transformed gene is expressed in transgenic flies. However, genetic complementation analysis indicated that the QIII locus and the rp21 gene are not identical. Implications of these findings for the relationship between Minutes and ribosomal protein genes are discussed. 相似文献
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Sigrid Jauris Karl P. Rücknagel Wolfgang H. Schwarz Peter Kratzsch Karin Bronnenmeier Walter L. Staudenbauer 《Molecular & general genetics : MGG》1990,223(2):258-267
Summary The nucleotide sequence of the celZ gene coding for a thermostable endo--1,4-glucanase (Avicelase I) of Clostridium stercorarium was determined. The structural gene consists of an open reading frame of 2958 by which encodes a preprotein of 986 amino acids with an Mr of 109000. The signal peptide cleavage site was identified by comparison with the N-terminal amino acid sequence of Avicelase I purified from C. stercorarium culture supernatants. The recombinant protein expressed in Escherichia coli is proteolytically cleaved into catalytic and cellulose-binding fragments of about 50 kDa each. Sequence comparison revealed that the N-terminal half of Avicelase I is closely related to avocado (Persea americana) cellulase. Homology is also observed with Clostridium thermocellum endoglucanase D and Pseudomonas fuorescens cellulase. The cellulose-binding region was located in the C-terminal half of Avicelase I. It consists of a reiterated domain of 88 amino acids flanked by a repeated sequence about 140 amino acids in length. The C-terminal flanking sequence is highly homologous to the non-catalytic domain of Bacillus subtilis endoglucanase and Caldocellum saccharolyticum endoglucanase B. It is proposed that the enhanced cellulolytic activity of Avicelase I is due to the presence of multiple cellulose-binding sites. 相似文献
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In this paper we identify new genetic profiles of eight Latin American cat populations. In addition, we combine data from
the present study and previously published data on 70 other American and European populations to discuss (1) the points of
introduction of mutant alleles for cat coat phenotypes from Europe into Latin America, (2) the heterozygosity levels at these
loci in the current Latin American cat populations, (3) the level of genetic heterogeneity among Latin American cat populations,
and how this compares with levels found in North American and European cat populations, and (4) how many different cat gene
pools are currently present in Latin America. We also include in our purview historical records of human migrations from Europe
to and within the Americas. Our analyses clearly support the view that the current genetic profiles and structuring of cat
populations in Latin America can be largely explained by the historical migration patterns of humans.
This work is dedicated to the memory of Dr Roy Robinson. May he rest in peace. 相似文献