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PubMed1977

Tactile sensitivity: development of a behavioral responses checklist.

Tactile defensiveness or sensitivity to being touched is a phenomenon observed by therapists during clinical testing and is reported based only on subjective data. The purpose of this study was to develop a more objective means of identifying this phenomenon. Videotaped observations of five-year-old boys being administered the Southern California Kinesthesia and Tactile Perception Test battery were used to identify behavioral reactions indicative of sensitivity to tactile stimulation. The population tested for a wide range of behaviors included hyperactive and normal five-year-old boys. These reactions were defined and categorized into a checklist of tactile-sensitive behaviroal responses. This checklist was then used on videotapes of 10 five-year-old boys by two raters to establish a measure of the reliability of this method of observing and recording behaviors. A reliability of .89 agreement with consensus was reached. These behavioral categories offer objective guides in identifying children with tactile defensiveness or sensitivity to tactile stimulation.

Child Behavior↗
PubMed2004

Immobilization of infant fecal microbiota and utilization in an in vitro colonic fermentation model.

Bacteria isolated from infant feces were immobilized in polysaccharide gel beads (2.5% gellan gum, 0.25% xanthan gum) using a two-phase dispersion process. A 52-day continuous culture was carried out in a single-stage chemostat containing precolonized beads and fed with a medium formulated to approximate the composition of infant chyme. Different dilution rates and pH conditions were tested to simulate the proximal (PCS), transverse (TCS), and distal (DCS) colons. Immobilization preserved all nine bacterial groups tested with survival rates between 3 and 56%. After 1 week fermentation, beads were highly colonized with all populations tested (excepted Staphylococcus spp. present in low numbers), which remained stable throughout the 7.5 weeks of fermentation, with variations below 1 log unit. However, free-cell populations in the circulating liquid medium, produced by immobilized cell growth, cell-release activity from gel beads, and free-cell growth, were altered considerably by culture conditions. Compared to the stabilization period, PCS was characterized by a considerable and rapid increase in Bifidobacterium spp. concentrations (7.4 to 9.6 log CFU/mL), whereas Bifidobacterium spp., Lactobacillus spp., and Clostridium spp. concentrations decreased and Staphylococcus spp. and coliforms increased during TCS and DCS. Under pseudo-steady-state conditions, the community structure developed in the chemostat reflected the relative proportions of viable bacterial numbers and metabolites generally encountered in infant feces. This work showed that a complex microbiota such as infant fecal bacteria can be immobilized and used in a continuous in vitro intestinal fermentation model to reproduce the high bacterial concentration and bacterial diversity of the feces inoculum, at least at the genera level, with a high stability during long-term experiment.

Analysis of Variance↗
PubMed1986

Prevalence in human beings of antibodies to Chlamydia IOL-207, an atypical strain of chlamydia.

Samples of serum from 18353 persons from the U.K. and abroad, were tested for type-specific antibodies to Chlamydia spp. Antibodies to an atypical strain, Chlamydia IOL-207, were detected in each population tested. Overall, the prevalence of these antibodies (19.9%) was similar to that of antibodies to C. trachomatis (21.6%). In the U.K., antibodies to C. IOL-207 were rare in children under the age of 5 years but became more common with increasing age. In adults the prevalence of these antibodies increased annually between 1979 and 1984. Antibodies to C. IOL-207 were not associated with sexually transmitted disease and only rarely with ocular disease. Their association with a common complaint such as mild respiratory illness is postulated. The presence of these antibodies within a population may lead to the over-diagnosis of C. trachomatis infections or psittacosis if only genus-specific serological tests are used.

Adolescent↗
PubMed2003

A cyclophilin gene marker confirming geographical differentiation of Norway spruce populations and indicating viability response on excess soil-born salinity.

A newly identified cyclophilin-encoding cDNA clone was used to design a codominant inherited EST-PCR marker in Norway spruce. The study of the current minor polymorphism revealed a geographically structured differentiation pattern across 17 test populations, showing a slight clinal variation south-north through Europe. Based on the frequency of alleles, isolation-by-distance analysis and the Ewens-Watterson test, we conclude that a selectively neutral random-drift mutation recently occurred within the Alpine population group, thus being responsible for the genetic variation detected. Analysis of tolerant and susceptible subsets of two adjacent Bavarian spruce populations affected by soil-born NaCl pollution, revealed that the cyclophilin marker locus also confirms biased genotype frequencies. Considering an unlinked PCR marker of a ribosomal protein-encoding EST clone, deviations between pooled tolerant subsets and pooled sensitive subsets were proven to be more significant for two-locus homozygous genotypes than for each locus alone. We suggest that both loci are linked to adaptive genomic regions. Their potential to test the feasibility of marker-assisted selection of both NaCl-tolerant and drought resistant tree populations is discussed.

Adaptation, Physiological↗
PubMed2001

Multiplex amplified product-length polymorphism analysis for rapid detection of human mitochondrial DNA variations.

A number of mutations in coding and noncoding regions of mitochondrial DNA (mtDNA) have previously been studied. In the present study, we simultaneously typed six mutation sites in the coding region by use of amplified product-length polymorphism (APLP) analysis. The mtDNA variations of 2471 individuals from 20 populations of Japanese, Korean, Chinese, and German were examined and classified into 18 haplotypes. Two of these haplotypes, B1 (estimated ancestral haplotype) and C1, were distributed among all populations tested. However, the haplotypes A1, A2, B2, B3, and C2 were mostly restricted to the Mongoloid populations, whereas haplotypes B5 and C5 appeared almost exclusively in the German population. Phylogenetic analysis by the neighbor-joining method revealed that the Japanese populations were more closely related to each other than to the other East Asian populations surveyed. The multiplex APLP method is suitable for large-scale screening studies of mtDNA variability because it is both rapid and economical.

DNA, Mitochondrial↗
PubMed2005

Genetic structure of wild rice Oryza glumaepatula populations in three Brazilian biomes using microsatellite markers.

The existence of Oryza glumaepatula is threatened by devastation and, thus, the implementation of conservation strategies is extremely relevant. This study aimed to characterize the genetic variability and estimate population parameters of 30 O. glumaepatula populations from three Brazilian biomes using 10 microsatellite markers. The levels of allelic variability for the SSR loci presented a mean of 10.3 alleles per locus and a value of 0.10 for the average allelic frequency value. The expected total heterozygosity (H(e)) ranged from 0.63 to 0.86. For the 30 populations tested, the mean observed (H(o)) and expected heterozygosities (H(e)) were 0.03 and 0.11 within population, respectively, indicating an excess of homozygotes resulting from the preferentially self-pollinating reproduction habit. The estimated fixation index ( (IS) ) was 0.79 that differed significantly from zero, indicating high inbreeding within each O. glumaepatula population. The total inbreeding of the species ((IT) ) was 0.98 and the genetic diversity indexes among populations, (ST) and (ST), were 0.85 and 0.90, respectively, indicating high genetic variability among them. Thus, especially for populations located in regions threatened with devastation, it is urgent that in situ preservation conditions should be created or that collections be made for ex situ preservation to prevent loss of the species genetic variability.

Alleles↗
PubMed1981

Trophic activities for dorsal root and sympathetic ganglionic neurons in media conditioned by Schwann and other peripheral cells.

We describe here the use of 3 established nerve growth factor (NGF) targets (cultured neurons from dissociated chick embryo sympathetic ganglia, and chick embryo or neonatal mouse dorsal root ganglia) to investigate neuronotrophic activities in conditioned media (CMs) from: (i) chick embryo heart; (ii) purified mouse Schwann cells; and (iii) clonal rat Schwannoma RN22 cells. In chick sympathetic and mouse dorsal root ganglionic cultures, all 3 CMs supported survival of the same number of neurons as did mouse submaxillary NGF, and in most cases no increased survival resulted from concurrent administration of NGF and any one CM. NGF and CM activities were quantitated in each of the responsive cell systems. No differences were seen when either test population was used for the same agent, or when different CMs were examined on the same test cells. The CM activity, unlike that of NGF, was not blocked by even excess amounts of antiserum against mouse submaxillary NGF. The neuronotrophic activity of CMs appears to reside with macromolecular constituents. None of the CMs displayed trophic activity on chick embryo dorsal root ganglionic neurons. However, at least one of them (RN22 medium) had drastic effects on these ganglionic cells even in the presence of NGF, leaving open the possibility of a 'toxic' factor overriding putative trophic agents.

Animals↗
PubMed2006

The effect of decreased visual acuity on clinical color vision testing.

PURPOSE: Evaluate the effect of visual acuity on color vision testing. DESIGN: University based clinical experimental study. METHODS: Right eyes of 12 healthy subjects were fogged with plus lenses to logMAR 1.88 and assessed with D-15 panel, Ishihara, and Hardy-Rand-Rittler (HRR) plates. Subjects were tested at lesser degrees of fogging, 0.1 logMAR intervals. The acuity at which 5% of the population tests abnormally was estimated as follows. The average acuity at which a 10% reduction in correct responses occurred was determined. From this, two standard deviations were subtracted. Examination devices were compared using repeated measures analysis of variance. RESULTS: Color vision testing did not significantly differ from baseline up to logMAR 1.40 (D-15 panel), 1.10 (HRR plates), and 0.72 (Ishihara plates). Testing devices were significantly different (P < .005). CONCLUSIONS: Color vision testing is accurate up to logMAR 1.40 (20/501) with D-15 panel, 1.10 (20/252) with HRR plates, and 0.72 (20/106) with Ishihara plates.

Adult↗
PubMedDate not supplied

The Yt blood groups in Israeli Jews, Arabs, and Druse.

The Yta and Ytb allelic frequencies were determined by examining the red cells of 1683 blood samples from Israeli Jews, Arabs, and Druse with anti-Yta and -Ytb. The Ytb allelic frequencies ranged between 0.1005 and 0.1522 in the Jewish communities and were 0.1294 and 0.1429 in the Arab and Druse communities, respectively. These are the highest Ytb allelic frequencies observed so far in any population tested, so the Yt blood group system can be used as a genetic marker in these populations. No factors were recognized that may have influenced the selection for the Ytb allele.

Alleles↗
PubMed1976

Chromosome studies in wild populations of D. melanogaster.

Chromosome studies of wild D. melanogaster populations from Missouri, Mississippi, Louisiana and Texas uncovered 58 inversions. Six were common and cosmopolitan; 52 were new, rare and generally endemic. In one of two Missouri populations tested, structurally heterozygous females carried significantly more sperm at capture than did the homozygotes. In both populations comparisons of wild sperms with the females carrying them indicated significant positive assortative mating and an excess production of homozygotes among the F1 progeny. Wild females structurally heterozygous in up to three major autosomal arms showed no associated nondisjunctional egg lethality; those heterozygous in all four arms produced from 0% to 24% dead eggs, suggesting the presence of intrapopulational gene modifiers of meiosis. Texas populations supported on windfall citrus fruit showed a slight but significant difference in inversion frequencies between flies breeding on oranges and those breeding on grapefruit. Within these populations inversions were not distributed at random among individuals; rather there was an observed excess of individuals carrying intermediate numbers, and a deficiency of those carrying very few or very many inversions. While there was no significant linkage disequilibrium associated with this central tendency, there was a significant interchromosomal interaction: flies carrying inversions in chromosome 2 tended not to carry them in chromosome 3, and vice versa.

Animals↗
PubMed1993

Detection of Mycobacterium leprae nasal carriers in populations for which leprosy is endemic.

In order to better understand the role of Mycobacterium leprae nasal carriage in the maintenance of infection reservoirs and transmission of leprosy, we applied a polymerase chain reaction (PCR) that detected a 531-bp fragment of the pra gene of M. leprae on nasal swab specimens collected through a total population survey from individuals living in an area in which leprosy is endemic. Among the total tested population of 1,228 people, 7.8% were found to be PCR positive. PCR positivity was shown to be randomly distributed among the population for which leprosy is endemic. No association was observed between PCR positivity, age, or sex. The observed distribution of PCR positivity among households of different sizes confirmed the expected values, with the exception of two households, each with three people with PCR-positive nasal swab specimens. Although nasal carriage does not necessarily imply infection or excretion of bacilli, the finding of nasal carriage supports the theory of a disseminated occurrence of M. leprae in populations for which leprosy is endemic.

Adolescent↗
PubMed1989

Heterozygote deficiency in natural populations of Aedes caspius Pallas from Egypt.

Aedes caspius Pallas populations from the Mediterranean regions are genetically highly polymorphic, and may diverge into 2 genetically isolated forms. We examined the genetic structure of 3 mosquito populations from Faiyum oasis, using starch gel electrophoresis at 8 gene loci, from which only one was monomorphic. Genetic variability was high (A = 1.97; H = 0.12; P = 54.2, 66.7). Eleven out of 16 population--enzyme combinations with variability exhibited heterozygote deficiency from Hardy--Weinberg expectations. These results suggest that tested populations represent a mosquito complex, although no genetic divergence was detected (D = 0.012) since presumed sympatric gamodemes were sampled as a single population. It is of prime importance to detect cryptic gamodemes and to elucidate the present status of Ae. caspius, as this may greatly influence control strategies.

Aedes↗
PubMed1989

Proficiency testing in a medical-needs context.

Proficiency testing by State and Federal agencies is an ongoing activity of clinical laboratories and an occasional source of anxiety; strict statistical evaluations of "snapshot" laboratory values are inappropriate and medical-needs criteria should be used. The quality of laboratory results largely depends on available technology. Fortunately, for most of the common clinical chemistry analytes there has been a steady reduction of imprecision during the past 20 years. Proficiency testing may have been the stimulus for this improved performance. Medical-needs criteria differ, depending on the testing goal. For proficiency testing, population screening criteria are appropriate, e.g., the College of American Pathologists fixed criteria for the common tests. Stricter criteria are needed for short-term (inpatient) and long-term (outpatient) monitoring of laboratory data. Explicit proficiency-testing limits are given here for nine of the common clinical chemistry tests for each of the three medical-needs criteria described above. The limits consider total error--i.e., bias from the believed correct value, and imprecision. Rather broad limits are acceptable for the commonly performed enzyme tests when used for screening purposes.

Blood Chemical Analysis↗
PubMed1979

Clinical experience with brain stem audiometry performed under general anesthesia.

Hearing tests were given to 22 difficult-to-test children using brain stem audiometry performed under general anesthesia. The effect of halothane and sodium thiopental on the brain stem response was assessed as well as the feasibility of using this technique with a difficult-to-test population. No effect on brain stem responses was observed to various levels of anesthesia. Successful hearing tests were carried out on all the children and results were helpful in their management. Brain stem audiometry perfromed under general anesthesia appears to be an effective and helpful technique for testing challenging diagnostic cases.

Adolescent↗
PubMed2006

Analysis of polymorphisms of the interleukin-18 gene in type 1 diabetes and Hardy-Weinberg equilibrium testing.

Recently, the interleukin-18 cytokine gene (IL18) was reported to be associated with type 1 diabetes. In the present report, we calculated that the reported genotypes of the two 5' region/promoter single nucleotide polymorphisms (SNPs), -607 (C-->A) (rs1946518) and -137 (G-->C) (rs187238), were not in Hardy-Weinberg equilibrium (HWE). We therefore investigated the association of the -607 and -137 SNPs in a U.K. type 1 diabetic Caucasian case-control collection (1,560 case and 1,715 control subjects tested at -607 and 4,323 case and 4,610 control subjects tested at -137) as well as a type 1 diabetic Caucasian collection comprised of families of European ancestry (1,347 families tested at -137 and 1,356 families tested at -607). No evidence for association with type 1 diabetes was found, including for the -607 A/A and C/A genotypes. To evaluate whether common variation elsewhere in the gene was associated with disease susceptibility, we analyzed eight IL18 tag SNPs in a type 1 diabetic case-control collection (1,561 case and 1,721 control subjects). No evidence for association was obtained (P = 0.11). We conclude that common allelic variation in IL18 is unlikely to contribute substantially to type 1 diabetes susceptibility in the populations tested and recommend routine application of tests for HWE in population-based studies for genetic association.

Alleles↗
PubMed2004

Chlamydia trachomatis in the United Kingdom: a systematic review and analysis of prevalence studies.

OBJECTIVES: To undertake a systematic review to obtain estimates of genital Chlamydia trachomatis prevalence in various populations in the United Kingdom and Ireland; to determine which populations have the highest rates of infection; and to explore the most important determinants of infection. METHODS: Electronic databases were searched using the keywords "chlamydia" and "England," "Wales," "UK," "Scotland," "Ireland," or "Britain." Additional unpublished data and references were solicited from experts. Studies were included in the analysis if C trachomatis prevalence was reported, and if they met inclusion criteria. Nine variables identified as potentially important descriptors of chlamydia prevalence were extracted from each study and analysed using various logistic regression models. Only studies reporting prevalence in female populations were included in the models, because there were few data from males. RESULTS: 357 studies were identified using the search methods, 90 of which met inclusion criteria, and 19 of which contributed to the final model. The most influential variables on prevalence were age and setting of the population tested. In general practice surgeries, the under 20 year old age group had an estimated prevalence of 8.1% (95% CI 6.5 to 9.9), 20-24 year olds 5.2% (95% CI 4.3 to 6.3), 25-29 year olds 2.6% (95% CI 2.0 to 3.3), decreasing to 1.4% (95% CI 1.0 to 1.9) in those aged over 30 years. Overall, healthcare settings had higher prevalence estimates than population based studies. For example, among under 20 year olds, estimates were 17.3% (95% CI 13.6 to 21.8) in genitourinary medicine clinics, 12.6% (95% CI 6.4 to 23.2) in antenatal clinics, 12.3% (95% CI 9.8 to 15.3) in termination of pregnancy clinics, 10.7% (95% CI 8.3 to 13.8) in youth clinics, 10.0% (95% CI 8.7 to 11.5) in family planning clinics, and 8.1% (95% CI 6.5 to 9.9) in general practice, compared to 5.0% (95% CI 3.2 to 7.6) in population based studies. The type of test, specimen used, date, and location of test were not strongly associated with chlamydia prevalence. CONCLUSION: The chlamydia prevalence estimates by age and setting from the model may be used to inform chlamydia screening strategies. The systematic review revealed much heterogeneity in the studies identified, but with clear patterns of prevalence. It also indicated gaps in the knowledge about chlamydia prevalence in certain subgroups such as men and the general population.

Adolescent↗
PubMed1990

Prevalence of antibodies interactive with HTLV-I antigens in selected Solomon Islands populations.

Serum samples obtained in 1986 from healthy individuals in three distinct Solomon Islands populations were screened for antibodies to human lymphotropic virus type I (HTLV-I). One of the populations tested lives on the remote Polynesian outlier atoll, Ontong Java. The other two groups, the Baegu and the Lau, are Melanesians living on Malaita, the most populous of the larger Solomon Islands. Eighty-eight of a total of 601 (14.6%) sera tested were repeatably reactive in an enzyme-linked immunosorbent assay (ELISA) that uses as antigen a lysate of HTLV-I viral particles. The prevalence of antibodies interactive with HTLV-I viral particles. The prevalence of antibodies interactive with HTLV-I antigens varied among the three groups, ranging from 8.5% (16/188) in the Baegu, through 13% (7/54) in the Lau, to 18.1% (65/359) among the Ontong Java population. The specificity of the screening ELISA was confirmed by protein immunoblot. No serum samples were obtained from children under 9 years of age. Although 121 of the 601 sera came from children between the ages of 9 and 19, none of these were reactive in the HTLV-I ELISA. Starting in the third decade, the prevalence of HTLV-I seropositivity increased with age, from 8.8% (10/113) between the ages of 20 and 29 to a peak of 25.9% (15/58) and 25% (15/60) in the sixth and seventh decade, respectively. This age-specific prevalence pattern is strikingly similar to that which is seen in populations where HTLV-I infection is endemic.

Adolescent↗
PubMedDate not supplied

Genetic variation in susceptibility to Marek's disease in a commercial broiler population.

Two commercial broiler pure lines that were previously identified to differ in their susceptibility to Marek's disease (MD) were line-crossed to generate an F1 population. Eight F1 males were randomly mated to four or five F1 females to produce an F2 test population that would be segregating for genes affecting MD. All F2 progeny (four hatches) were pedigreed at hatch and placed in colony houses as nonvaccinated. At 5 days of age, they were challenged intraabdominally with MD virus RB1B. Clinical signs, mortality, and gross and microscopic lesions were recorded during the MD challenge. At 8 wk postchallenge, all remaining birds were euthanatized and necropsied. During the MD challenge of the first two hatches, we observed that several severely stunted broilers originated from certain families and the differences in body weight among birds appeared as early as 3 wk postchallenge. To confirm this observation, body weight at 6 wk postchallenge was determined for all surviving birds in hatches 3 and 4 (n = 242). Genetic variation in body weight among broiler sire families was apparent; the average body weight for males at this time was 2.07 kg, whereas with females, it was 1.87 kg. At least 12.2% of the broilers, including both sexes, weighed less than 1 kg ("severely stunted") at this time. The incidence of these growth-stunted birds within each broiler sire family ranged from 0 to 26% and for dam families, 0 to 60%. Correlation analyses between stunting and other MD-associated traits revealed that the incidence of stunting had a significant and positive association with paralysis (r = 0.50). Therefore, the data suggest that there may be a genetic component affecting body weight loss during MD infection. The genetic component is speculated to affect susceptibility to MD paralysis with an indirect effect on the body weight of birds. The significance of this finding is best exemplified by the identification of a broiler sire family with over 26% of its progeny affected by this MD-associated trait.

Animals↗