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PubMed2000

Monitoring of the European corn borer (Lepidoptera: Crambidae) in central Maine.

Pheromone trap types and within-field trap locations were compared for their effectiveness in monitoring the flight activity of European corn borer, Ostrinia nubilalis (Hübner), and its relationship to egg mass density and crop damage in sweet corn in central Maine from 1995 to 1996. The use of both 3:97 Z:E-11-tetradecenyl acetate and 97:3 Z:E-11 tetradecenyl acetate pheromone blends confirmed that European corn borer in central Maine is attracted to both pheromone lure types. European corn borer moths were captured predominantly with the E-lure type than with the Z-lure type in both years. The Scentry Heliothis trap was more effective than the Multi-Pher trap, but similar to the pheromone-baited water pan trap for monitoring European corn borer flights. With the Scentry Heliothis trap, the grassy border and 1st corn rows were the best locations for moth capture during the early flight period, but during the peak flight period, traps located in the middle of the field caught the most moths. Corn damage was recorded before moth captures in some sites and before egg mass counts in others, indicating poor efficacy of traps for early flights. Significant and positive correlations were found between moth captures in the midfield location and egg mass counts, and corn leaf damage, and between egg mass counts and corn leaf damage. However, low coefficients of variation suggest that pheromone trap captures were not good predictors of European corn borer leaf damage in sweet corn.

Animals↗
PubMed1990

Alternative splicing of the human alpha 2(VI) collagen gene generates multiple mRNA transcripts which predict three protein variants with distinct carboxyl termini.

We recently reported the isolation and sequencing of two classes of human alpha 2(VI) collagen cDNA clones which share common sequences for the first two-thirds of the molecule but contain a different sequence of either 607 or 887 base pairs at their 3' ends (Chu, M.-L., Pan, T.-C., Conway, D., Kuo, H.-J., Glanville, R. W., Timpl, R., Mann, K., and Deutzmann, R. (1989) EMBO J. 8, 1939-1946). In the present study, we report the sequence of another cDNA clone, which is identical to one class of the previously isolated cDNAs except for a 293-base pair insertion between the common and variable regions. Together, the different classes of cDNAs, referred to as the alpha 2C2, alpha 2C2a, and alpha 2C2a' predict three variant alpha 2 chains of type VI collagen with carboxyl globular domains of 429, 328, and 238 amino acid residues, respectively. In order to explore the mechanisms by which the variations are generated, we isolated and characterized the 3' end of the human alpha 2(VI) collagen gene. The carboxyl globular domain was found to be encoded by six exons which appear to delineate its structural subdomains. The exon/intron arrangement clearly demonstrated that the cDNA variants arose from alternative splicing events by mutually exclusive utilization of the last two exons in conjunction with the selective usage of an internal splice acceptor site in the penultimate exon. The presence of the corresponding mature mRNA transcripts (3.2-3.5 kilobase pairs (kb] in human fibroblasts was shown by Northern blot hybridization, S1 nuclease protection assay, and the polymerase chain reaction. The results indicated that the alpha 2C2 mRNA is the major species, whereas the alpha 2C2a and alpha 2C2a' are the minor forms. Northern blot hybridization also revealed an alpha 2(VI) collagen mRNA of 6.0 kb. This mRNA retained a 2.3-kb intron located between the two alternatively spliced exons and predicted a translational product that is the same as the alpha 2C2a variant.

Amino Acid Sequence↗
PubMed2006

Analyses of 5' regulatory region polymorphisms in human SLC22A6 (OAT1) and SLC22A8 (OAT3).

Kidney excretion of numerous organic anionic drugs and endogenous metabolites is carried out by a family of multispecific organic anion transporters (OATs). Two closely related transporters, SLC22A6, initially identified by us as NKT and also known as OAT1, and SLC22A8, also known as OAT3 and ROCT, are thought to mediate the initial steps in the transport of organic anionic drugs between the blood and proximal tubule cells of the kidney. Coding region polymorphisms in these genes are infrequent and pairing of these genes in the genome suggests they may be coordinately regulated. Hence, 5' regulatory regions of these genes may be important factors in human variation in organic anionic drug handling. We have analyzed novel single nucleotide polymorphisms in the evolutionarily conserved 5' regulatory regions of the SLC22A6 and SLC22A8 genes (phylogenetic footprints) in an ethnically diverse sample of 96 individuals (192 haploid genomes). Only one polymorphism was found in the SLC22A6 5' regulatory region. In contrast, seven polymorphisms were found in the SLC22A8 5' regulatory region, two of which were common to all ethnic groups studied. Computational analysis permitted phase and haplotype reconstruction. Proximity of these non-coding polymorphisms to transcriptional regulatory elements (including potential sex steroid response elements) suggests a potential influence on the level of transcription of the SLC22A6 and/or SLC22A8 genes and will help define their role in variation in human drug, metabolite and toxin excretion. The clustering of OAT genes in the genome raises the possibility that nucleotide polymorphisms in SLC22A6 could also effect SLC22A8 expression, and vice versa.

Animals↗
PubMedDate not supplied

A perspective on medical infrared imaging.

Since the early days of thermography in the 1950s, image processing techniques, sensitivity of thermal sensors and spatial resolution have progressed greatly, holding out fresh promise for infrared (IR) imaging techniques. Applications in civil, industrial and healthcare fields are thus reaching a high level of technical performance. The relationship between body temperature and disease was documented since 400 bc. In many diseases there are variations in blood flow, and these in turn affect the skin temperature. IR imaging offers a useful and non-invasive approach to the diagnosis and treatment (as therapeutic aids) of many disorders, in particular in the areas of rheumatology, dermatology, orthopaedics and circulatory abnormalities. This paper reviews many usages (and hence the limitations) of thermography in biomedical fields.

Diagnostic Imaging↗
PubMed1975

Renal urate excretion in animal models.

Several aspects of the comparative physiology and pharmacology of renal urate handling are considered; with special attention to bidirectional transport, the existence of intrarenal urate synthesis and degradation in certain species, and the nature and sites of the reabsorptive and secretory processes. Interspecies variations in the sensitivity of the kidney to uricosuric agents and the degree of specificity of the secretory mechanism are discussed. A variety of techniques, especially as applied in certain nonhuman primates, have led to a concept of very rapid trans-tubular fluxes of urate--a concept which may apply in man.

Allopurinol↗
PubMed1994

A retrospective study of DNA ploidy of transitional cell carcinoma of urinary bladder using flow cytometry.

Transitional cell carcinoma is the most common malignancy of urothelial origin in urinary bladder. Its aggressive potential cannot be reliably predicted from the histologic appearance alone. Recently, there has been extensive studies of DNA ploidy using flow cytometry in prospective analysis of bladder tumors with fresh tissue. Techniques for the preparation of paraffin embedded tissue have been developed and successfully applied in retrospective evaluation of bladder tumors. These studies had demonstrated the correlation between histological grading and DNA ploidy, and between clinical staging and DNA ploidy. Our retrospective study showed that the cytometric method is superior to histologic grading in the predictability of patient's survival, especially in the low grade (grades 1 and 2) group. In the preparation of paraffin embedded tissue, the high background debris and wide range of coefficients of variation had some interference in the interpretation for the histogram of FCM (only 80% of the cases studied are interpretable). This interference might be due to the variation of conditions of tissue processing and fixation. The evaluation of S phase fraction and G2/M fraction is also difficult to perform because of the same problem. There was an encouraging result in the evaluation of DNA ploidy using flow cytometry with paraffin embedded tissue, although a relatively small number of patients were included in this study. The value of this technique application in clinical evaluation of the prognosticity was obvious.

Adult↗
PubMedDate not supplied

Variations in molar enamel thickness among primates.

Because of its hardness, resistance to abrasion and its influence on crown morphology, molar enamel thickness is an important factor in adaptation of the dentition to the diet. Enamel thickness has also been discussed extensively in relation to the phylogenetic relationships among the hominoids. The aims of this study were: (1) to analyse enamel thickness/tooth size relationships among primates as a whole, and (2) to evaluate variations in enamel thickness among hominoids against the background of the other primates. We employed measures of tooth size, and of enamel thickness and quantity based on measurements of areas in longitudinal sections of 125 molars of 39 species. Among primates, there were two grades of enamel thickness, prosimians having thinner enamel for a given tooth size or body weight than anthropoids. The scaling of enamel thickness with tooth size and body weight tended to show positive allometry among anthropoids. Comparison of hominoid enamel thicknesses with that in anthropoids led to the conclusion that Hylobates has enamel of average thickness, Homo has thick enamel and Gorilla has thin enamel, while Pan and Pongo had average or thin enamel, depending on tooth type. These results may be relevant to considerations of hominoid evolution.

Analysis of Variance↗
PubMed1997

Evidence for dominant wild female chimpanzees investing more in sons

Parents are expected to invest more resources in the offspring gender that promises more grandchildren. In a variety of vertebrate species skewed sex ratio at birth and differential parental investment in sons and daughters have been documented. Wild chimpanzees, Pan troglodytesliving in the Tai National Park, Cote d'Ivoire, were followed for 15 years. This community followed the typical species pattern in that males showed natal philopatry and the sex ratio at birth was almost 1:1. An analysis of 33 inter-birth intervals revealed that dominant females invested about 2 years more in sons, whereas subdominant females invested about 11 months more in daughters. The first difference is significant. Sons of dominant females had higher survival than other youngsters. The benefit of such a facultative investment is discussed. The absence of such a differential investment by mothers in other chimpanzee populations is compatible with an explanation based on variations within the female-biased dispersal pattern in this species and the possible role of maternal condition.Copyright 1997 The Association for the Study of Animal Behaviour1997The Association for the Study of Animal Behaviour

Journal Article↗
PubMed2005

Role of transmembrane segment 5 of the plant vacuolar H+-pyrophosphatase.

Vacuolar H+-translocating inorganic pyrophosphatase (V-PPase; EC 3.6.1.1) is a homodimeric proton translocase consisting of a single type of polypeptide with a molecular mass of approximately 81 kDa. Topological analysis tentatively predicts that mung bean V-PPase contains 14 transmembrane domains. Alignment analysis of V-PPase demonstrated that the transmembrane domain 5 (TM5) of the enzyme is highly conserved in plants and located at the N-terminal side of the putative substrate-binding loop. The hydropathic analysis of V-PPase showed a relatively lower degree of hydrophobicity in the TM5 region as compared to other domains. Accordingly, it appears that TM5 is probably involved in the proton translocation of V-PPase. In this study, we used site-directed mutagenesis to examine the functional role of amino acid residues in TM5 of V-PPase. A series of mutants singly replaced by alanine residues along TM5 were constructed and over-expressed in Saccharomyces cerevisiae; they were then used to determine their enzymatic activities and proton translocations. Our results indicate that several mutants displayed minor variations in enzymatic properties, while others including those mutated at E225, a GYG motif (residues from 229 to 231), A238, and R242, showed a serious decline in enzymatic activity, proton translocation, and coupling efficiency of V-PPase. Moreover, the mutation at Y230 relieved several cation effects on the V-PPase. The GYG motif presumably plays a significant role in maintaining structure and function of V-PPase.

Amino Acid Sequence↗
PubMed1998

Codon usage in highly expressed genes of Haemophillus influenzae and Mycobacterium tuberculosis: translational selection versus mutational bias.

Biases in the codon usage and base compositions at three codon sites in different genes of A+T-rich Gram-negative bacterium Haemophillus influenzae and G+C-rich Gram-positive bacterium Mycobacterium tuberculosis have been examined to address the following questions: (1) whether the synonymous codon usage in organisms having highly skewed base compositions is totally dictated by the mutational bias as reported previously (Sharp, P.M., Devine, K.M., 1989. Codon usage and gene expression level in Dictyostelium discoideum: highly expressed genes do 'prefer' optimal codons. Nucleic Acids Res. 17, 5029-5039), or is also controlled by translational selection; (2) whether preference of G in the first codon positions by highly expressed genes, as reported in Escherichia coli (Gutierrez, G., Marquez, L., Marin, A., 1996. Preference for guanosine at first codon position in highly expressed Escherichia coli genes. A relationship with translational efficiency. Nucleic Acids Res. 24, 2525-2527), is true in other bacteria; and (3) whether the usage of bases in three codon positions is species-specific. Result presented here show that even in organisms with high mutational bias, translational selection plays an important role in dictating the synonymous codon usage, though the set of optimal codons is chosen in accordance with the mutational pressure. The frequencies of G-starting codons are positively correlated to the level of expression of genes, as estimated by their Codon Adaptation Index (CAI) values, in M. tuberculosis as well as in H. influenzae in spite of having an A+T-rich genome. The present study on the codon preferences of two organisms with oppositely skewed base compositions thus suggests that the preference of G-starting codons by highly expressed genes might be a general feature of bacteria, irrespective of their overall G+C contents. The ranges of variations in the frequencies of individual bases at the first and second codon positions of genes of both H. influenzae and M. tuberculosis are similar to those of E. coli, implying that though the composition of all three codon positions is governed by a selection-mutation balance, the mutational pressure has little influence in the choice of bases at the first two codon positions, even in organisms with highly biased base compositions.

Animals↗
PubMed2006

Morphometric and hormonal changes during the chimpanzee menstrual cycle.

BACKGROUND: Sex steroids affect many peripheral tissue sites in female mammals. Receptors for these hormones have been found in skin, fat, and bone. In women, these tissues can show morphological changes during the menstrual cycle that may be directly related to steroid secretion. METHODS: The present study was done on chimpanzees to document morphometric markers associated with these tissues (anogenital swelling volume, skin fold thickness as indicator of subcutaneous fat, bony diameters of mandible, wrist, and elbow) and to compare them with cyclic patterns of estradiol, progesterone, testosterone, gonadotropins, and prolactin. RESULTS: Swelling volume changed significantly over the menstrual cycle. All other morphometric parameters showed variation without statistical significance. Skin folds were thickest during the luteal phase. Bony diameters displayed similar but less distinctive changes. Testosterone correlated positively with diameter sites, inversely with subcutaneous fat. No relationships with either estradiol or progesterone were found. We assume that subcutaneous fat and morphometric bone parameters exhibit cycle-dependent changes that may be caused by changes in steroid secretion.

Animals↗
PubMed2026

Evaluating a Genome-Wide Polygenic Score for Handgrip Strength and Its Interplay with Leisure-Time Physical Activity Across the IGEMS Twin Cohorts.

PURPOSE: Polygenic scores (PGSs) may help assess genetic predisposition to multifactorial traits. We examined whether age, sex, and leisure-time physical activity (LTPA) modify the association between a PGS for handgrip strength (HGS) and measured HGS in older adults. METHODS: PGS for HGS (PGS hgs) , based on Pan-UK Biobank genome-wide association study data, was calculated for 5103 participants (aged 40-96; 44% women) from eight twin cohorts in Denmark, Sweden, Australia, the United States, and Finland within the IGEMS consortium. Sex-standardized HGS and self-reported LTPA were assessed cross-sectionally. Linear mixed models estimated associations between PGS hgs and HGS, including interactions with age, country, and LTPA, as well as an association between PGS hgs and LTPA. Fixed-effect within-pair models were conducted to assess environmental contributions. RESULTS: Higher PGS hgs was associated with greater HGS (&#x3b2; = 2.14, SE = 0.15, P < 0.001), explaining 4.6% of HGS variance overall, with modest variation across countries. In sex-stratified models, PGS hgs explained 5.2% of the variance in females and 4.3% in males. No statistically significant interaction with age was found. A significant PGS hgs &#xd7; LTPA interaction (&#x3b2; = -0.034, P = 0.013) indicated that the association between LTPA and HGS was more pronounced among individuals with lower PGS hgs . The within-pair models offered limited support for the independent environmental impact of LTPA. CONCLUSIONS: The PGS hgs was associated with measured HGS in the meta-analysis, highlighting the potential of PGSs to capture individual differences in strength-related traits across populations. The association of PGS hgs with HGS was moderated by LTPA, such that the beneficial impact of LTPA on HGS was greater among individuals with a lower genetic propensity for HGS.

Humans↗
PubMed2001

Diurnal variation of leptin entry from blood to brain involving partial saturation of the transport system.

The blood-brain barrier (BBB) regulates the amount of peripherally produced leptin reaching the brain. Knowing that the blood concentration of leptin has a circadian rhythm, we investigated whether the influx of leptin at the BBB followed the same pattern in three main sets of experiments. (a): The entry of 125I-leptin from blood to brain was measured in mice every 4 h, as indicated by the influx rate of 125I-leptin 1-10 min after an iv bolus injection. The blood concentration of endogenous leptin was measured at the same times. Blood leptin concentrations were higher at night and early morning (peak at 0800 h) and lower during the day (nadir at 1600 h). By contrast, the influx of 125I-leptin was fastest at 2000 h and slowest at 0400 h. Addition of unlabeled leptin (1 microg/mouse) significantly decreased the influx rate of 125I-leptin at all time points, indicating saturability of the transport system. The unlabeled leptin also abolished the diurnal variation of the influx of 125I-leptin. (b): The entry of 125I-leptin into spinal cord was faster than that into brain and showed a different diurnal pattern. The greatest influx occurred at 2400 h and the slowest at 0800 h. In spinal cord, unlike brain, unlabeled leptin (1 microg/mouse) neither inhibited the influx of 125I-leptin nor abolished the diurnal rhythm. (c): Higher concentrations of unlabeled leptin (5 microg/mouse) inhibited the uptake of 125I-leptin in spinal cord as well as in brain, but not in muscle. This experiment measured uptake 10 min after iv injection at 0600 h (beginning of the light cycle) and 1800 h (beginning of the dark cycle). Thus, influx of 125I-leptin into the CNS shows diurnal variation, indicating a circadian rhythm in the transport system at the BBB, saturation of the leptin transport system shows differences between the brain and spinal cord, and blood concentrations of leptin suggest that partial saturation of the transport system occurs at physiological concentrations of circulating leptin, contributing to the differing diurnal patterns in brain and spinal cord. Together, the results show that the BBB is actively involved in the neuroendocrine regulation of feeding behavior.

Animals↗
PubMed1992

Foods predictive of nutrient intake in Chinese diet in Taiwan: II. Vitamin A, vitamin B1, vitamin B2, vitamin C and calcium.

Dietary consumption data obtained by food weighing for 539 households in Taiwan in 1980-1981 were used to search for predictor foods of individual intake of several vitamins and calcium. Stepwise multiple regression analysis was carried out on food items that were univariately and significantly associated with nutrient intakes, to screen for the important predictors. Less than ten foods were enough to explain more than 90% of the interperson variation for vitamin A, vitamin B1, and vitamin B2. For vitamin C and calcium, 20 food items could explain only 87% of the variation. Salt, brown sugar, and soy bean sauce were selected among calcium predictors. The information on foods predictive of nutrient intake is useful in designing food frequency questionnaires and materials for nutrition education. Although this paper provides such information for Chinese living in Taiwan, some issues described (such as the need to assess spices) may have been overlooked and could be generalized to populations using stir-frying as a major cooking method.

Ascorbic Acid↗
PubMedDate not supplied

Craniodental variation in the African macaque, with reference to various Asian species.

Based on twenty-seven craniodental measurements and ratios derived from them, the relationship between the African macaque (M. sylvanus) and the others in Asia were examined with principal components analyses (PCA) and Euclidean distance analysis based upon prior discriminant function analyses (DFA). Results based on analyses of raw measurements indicate that the variation between species lies in the first axis of PCA; the species are dispersed according to their differences in size. The variation between sexes (sexual dimorphism) lies in the second axis. In the analyses of ratio variables, though these two patterns of separation remain orthogonal, they lie at approximately forty-five degrees to each axis. Variables relating to anterior teeth were found to play an important role in variation analysis, and this may be related to the special food preferences of these monkeys: more frequent usage of the incisor teeth for processing frugivorous diets than in other primates that are mainly folivorous. The results from Euclidean distance analyses indicate that the average distance of species within the Asian group is shorter than that between Asian and African groups regardless of sex and variable type. In addition the variation between African and Asian groups is larger than that within Asian group. Thus, it is reasonable to suggest that the African macaque has a range of measurements and ratios quite distinct from the species found in Asia (though the greatest separations result from the analyses of ratio data). These results therefore support the view that M. sylvanus may be regarded as an independent species group in the genus Macaca as proposed by Delson [1980].

Africa↗
PubMed2026

Systematic analysis of the type VII secretion system in Streptococcus gallolyticus subsp. gallolyticus reveals genomic diversity and functional associations.

Streptococcus gallolyticus subsp. gallolyticus (Sgg) is an opportunistic pathobiont associated with bacteremia, infective endocarditis, and colorectal cancer. However, the genomic diversity of this subspecies and the distribution of key virulence determinants, particularly the type VII secretion system (T7SS), remain poorly characterized. Here, we performed genomic analyses of 76 Sgg strains from diverse geographic and host origins. Core- and pan-genome analyses, multi locus sequence typing, and phylogenetic reconstruction revealed dominant sequence types (STs) that correlate with geographic origin or source of isolation. Furthermore, systematic characterization of the T7SS locus identified five new T7SS subtypes and demonstrated a strong association between T7SS subtype and ST. We further expanded the known repertoire of T7SS LXG domain-containing polymorphic toxins (LXG toxins) in Sgg substantially through genome-wide searches. Distinct distribution patterns were observed for the LXG toxins across the strains. Lastly, our data indicated that T7SS subtype was significantly associated with biofilm formation capacity of Sgg strains. Together, these findings advance our understanding of Sgg genomic diversity, reveal substantial lineage-associated variation in T7SS architecture and effector repertoires, and suggest a previously unrecognized connection between T7SS and biofilm formation in Sgg.

LXG toxins↗
PubMed1993

[Crohn's disease of the small intestine: place of surgery in 1992].

Crohn's disease (CD) is a chronic pan-enteric inflammatory disease of unknown etiology. Although treatment of CD of small intestine is at present principally medical, in the majority of cases surgical intervention is unavoidable, essentially to treat complications such as occlusion, intra- and/or extra-abdominal abscess, certain fistulae, intraperitoneal perforation, profuse hemorrhage and neoplastic degeneration. Surgery may also be indicated during acute episodes of corticotherapy resistant CD, and as a valid alternative to only partially effective long term corticoid treatment of an active chronic disease. Experience has shown that surgery should be as conservative as possible, "stricturoplasty" being the treatment of choice for stenotic lesions. Postoperative follow-up conditions have still to be formulated because of the marked variations in manifestations of recurrence of the disease.

Abscess↗
PubMed2005

Human F7 sequence is split into three deep clades that are related to FVII plasma levels.

It is widely accepted that FVII levels are strongly, consistently, and independently related to cardiovascular risk. These levels are influenced by genetic and environmental factors. Among the genetic factors, only a limited number of polymorphisms in the F7 gene have been reported, and they explain only a small proportion of the genetic variability. Recently, we have accomplished the complete dissection of the F7 quantitative trait locus responsible for all of the genetic variability observed in FVII levels. Now, we present the thorough study of the haplotype organization of F7 DNA sequence variation among individuals and the evolutionary processes that produced this variation, by sequencing 15 kb of genomic DNA sequence from the F7 locus in 40 unrelated individual (80 chromosomes) from the genetic analysis of idiopathic thrombophilia (GAIT) project as well as four non-human primate species. Our study revealed 49 polymorphisms, of which 39 SNPs were further considered. Genotyping of these DNA variations in the whole family-based GAIT sample helped resolve linkage phases, and a total of 37 distinct haplotypes were identified.Tajima's D was significantly positive in this sample, suggesting balancing selection. This parameter was a reflection of the phylogenetic structure of F7 haplotype, which was deeply split into three well-supported clades or haplogroups, suggesting that functional differences among F7 variants do not depend on a few single-site variations. Moreover, haplogroup 2 was associated with high FVII levels and haplogroup 3 with low levels. In this study, we have for the first time established a clear relation between genotypic variability structure and phenotypic variability of a particular quantitative trait involved in a complex disease.

Animals↗