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J K Thompson

Publications and source records attributed to J K Thompson.

At least 37 records · Page 2Linked to original sources
PubMed1999

Complete sequence of plasmid pLH1 from lactobacillus helveticus ATCC15009: analysis reveals the presence of regions homologous to other native plasmids from the host strain.

The complete sequence for plasmid pLH1 from Lactobacillus helveticus ATCC15009 has been determined. Analysis of the 19,360-bp primary sequence revealed a putative replication origin and initiation protein, information that could provide the basis for the construction of cloning vectors for L. helveticus. Evidence that pLH1 is theta-replicating could be deduced from the plasmid size, from the homology to the replication protein of the Bacillus natto theta-replicating plasmid pLS32, and from the identification of a putative resolvase gene (orf-195). Although 14 open reading frames capable of encoding polypeptides longer than 100 amino acids were identified, none, on the basis of homology with known sequences, appeared to encode a well-characterized trait relevant to milk fermentation. Plasmid pLH1 revealed regions of identity with the smaller cryptic plasmids (pLH2 and pLH3) from the same strain and with other tracts of DNA, including insertion sequence elements, from a variety of other lactic acid bacteria. The presence of such regions provides a basis for developing an explanation of the phenotypic variability observed in these bacteria. The plasmid also appears to possess a number of genetic elements present in other lactic acid bacterial plasmids, conservation of which would be consistent with an important functional or evolutionary role. It could be argued that the plasmid complement of L. helveticus ATCC15009 consists of parasitic entities concerned only with their own replication and survival.

Amino Acid Sequence↗
PubMed1998

Relation of self-image to body size and weight loss attempts in black women: the CARDIA study. Coronary Artery Risk Development in Young Adults.

It has been suggested that the prevalence of obesity in black women is high partly because self-image in black women is not strongly dependent on body size. To determine associations between self-image, body size, and dieting behavior among black women, the authors assessed an Appearance Evaluation Subscale (AES) score (range, 1-5), a Body Image Satisfaction (BIS) score (range, 2-11), and reported dieting behavior in a population-based sample of 1,143 black women aged 24-42 years from the fourth follow-up examination (1992-1993) of the Coronary Artery Risk Development in Young Adults (CARDIA) Study. Lower AES and BIS scores indicate poorer self-image and lower body size satisfaction, respectively. After adjustment for age, education, smoking, and physical activity, women in the lowest, middle, and highest tertiles of body mass index (weight (kg)/height (m)2) had mean AES scores of 3.7, 3.3, and 2.9, respectively (p < 0.001), and mean BIS scores of 7.8, 6.7, and 5.9, respectively (p < 0.001). After additional control for body mass index as a continuous variable, both AES and BIS scores were inversely related to ever dieting, current dieting, and previous weight loss of 10 pounds (4.5 kg) or more in all tertiles of body mass index. These results suggest that among black women, a higher body mass index is associated with poorer self-image and lower body size satisfaction and that these perceptions may be an avenue to promoting weight control.

Adolescent↗
PubMed1998

Assessment of body image disturbance in obesity.

Disturbance in body image has long been noted as one of the most distressing psychological factors for obese individuals. Yet, only in recent years have researchers and clinicians begun to appreciate the need to integrate systematic evaluation of this component into intervention programs. Accordingly, this mini-review offers an overview of selected strategies for the assessment of body image disturbance in obesity.

Body Constitution↗
PubMed1998

Evidence of plasticity in the pontocerebellar conditioned stimulus pathway during classical conditioning of the eyeblink response in the rabbit.

Electrical stimulation thresholds required to elicit eyeblinks with either pontine or cerebellar interpositus stimulation were measured before and after classical eyeblink conditioning with paired pontine stimulation (conditioned stimulus, CS) and corneal airpuff (unconditioned stimulus, US). Pontine stimulation thresholds dropped dramatically after training and returned to baseline levels following extinction, whereas interpositus thresholds and input-output functions remained stable across training sessions. Learning rate, magnitude of threshold change, and electrode placements were correlated. Pontine projection patterns to the cerebellum were confirmed with retrograde labeling techniques. These results add to the body of literature suggesting that the pons relays CS information to the cerebellum and provide further evidence of synaptic plasticity in the cerebellar network.

Animals↗
PubMed1997

Prognostic value of MIB-1 in advanced ovarian carcinoma as determined using automated immunohistochemistry and quantitative image analysis.

BACKGROUND AND OBJECTIVES: The monoclonal antibody MIB-1 is an immunohistochemical marker reacting most strongly with cells in late S phase, G2, and M portions of the cell cycle. This antibody, reactive in formalin-fixed, paraffin-embedded tissue, allows the quantitation of a proliferation index (PI) in both current clinical cases and archival material using a computerized image analyzer (CIA). METHODS: Since many laboratories make use of automated immunohistochemistry (AIH), this study was performed to explore the technical feasibility of using AIH (Ventana ES 320) in combination with CIA (CAS 200) to evaluate MIB-1 PI as a prognostic marker as assessed by overall survival in 50 archival (formalin-fixed, paraffin-embedded), advanced stage primary ovarian carcinomas. RESULTS: Exploratory methods confirmed that 15% was a cutpoint that could dichotomize these 50 patients into two prognostic groups based on overall survival. The median survival of patients whose carcinoma had a high MIB-1 expression (> or = 15%) was 16 months compared with 30 months in the patients whose tumors demonstrated low MIB-1 expression (< 15%, P = 0.01). After adjustment for age, MIB-1 retained its prognostic significance (P = 0.02). Patients 60 years and older had shorter survival than younger patients (P = 0.06), but these two groups did not differ with respect to PI (P = 0.76). Those patients with a negative second look laparotomy had a longer median survival of 70 months compared with 18.5 months in patients with a positive second look (P < 0.001); the median PIs were 17% and 27%, respectively (P = 0.36). There were no significant relationships between clinical stage, nuclear grade, DNA ploidy, p53, and either survival or PI. CONCLUSIONS: In this study, we concluded that the combination of AIH and CIA yielded a reliable quantitation of MIB-1 proliferative index and that this proliferative marker had prognostic significance in late stage ovarian carcinoma. Further studies in a larger group of patients are needed to confirm the relationship between proliferation index and other known clinicopathologic and genetic variables.

Antibodies, Monoclonal↗
PubMed1997

Overt and covert sexual abuse: relationship to body image and eating disturbance.

OBJECTIVE: To separate forms of overt and covert sexual abuse and assess their independent contribution to the development of body image and eating disturbance. METHOD: A new measure was developed--the Covert-Overt Sexual Abuse Questionnaire (COSAQ)--and correlated with levels of body image, eating disturbance, social desirability, self-esteem, and depression. RESULTS: Factor analyses on three independent samples yielded two distinct subscales which were labelled Overt and Covert. Each scale had excellent internal consistency and test-retest reliability. Regression analyses demonstrated the ability of the Covert factor to explain variance associated with body image disturbance and eating dysfunction beyond that accounted for by levels of social desirability, self-esteem, depression, and overt sexual abuse. DISCUSSION: These findings support the importance of a more "subtle" form of early trauma--covert sexual abuse--in the development of body image and eating-related problems.

Adaptation, Psychological↗
PubMed1997

Associative learning.

This chapter reviews evidence demonstrating the essential role of the cerebellum and its associated circuitry in the learning and memory of classical conditioning of discrete behavioral responses (e.g., eyeblink, limb flexion, head turn). It now seems conclusive that the memory traces for this basic category of associative learning are formed and stored in the cerebellum. Lesion, neuronal recording, electrical microstimulation, and anatomical procedures have been used to identify the essential conditioned stimulus (CS) circuit, including the pontine mossy fiber projections to the cerebellum; the essential unconditioned stimulus (US) reinforcing or teaching circuit, including neurons in the inferior olive (dorsal accessory olive) projecting to the cerebellum as climbing fibers; and the essential conditioned response (CR) circuit, including the interpositus nucleus, its projection via the superior cerebellar peduncle to the magnocellular red nucleus, and rubral projections to premotor and motor nuclei. Each major component of the eyeblink CR circuit was reversibly inactivated both in trained animals and over the course of training. In all cases in trained animals, inactivation abolished the CR (and the UR as well when motor nuclei were inactivated). When animals were trained during inactivation (and not exhibiting CRs) and then tested without inactivation, animals with inactivation of the motor nuclei, red nucleus, and superior peduncle had fully learned, whereas animals with inactivation of a very localized region of the cerebellum (anterior interpositus and overlying cortex) had not learned at all. Consequently, the memory traces are formed and stored in the cerebellum. Several alternative possibilities are considered and ruled out. Both the cerebellar cortex and the interpositus nucleus are involved in the memory storage process, suggesting that a phenomenon-like long-term depression (LTD) is involved in the cerebellar cortex and long-term potentiation (LTP) is involved in the interpositus. The experimental findings reviewed in this chapter provide perhaps the first conclusive evidence for the localization of a basic form of memory storage to a particular brain region, namely the cerebellum, and indicate that the cerebellum is indeed a cognitive machine.

Animals↗
PubMed1997

The conditioned eyeblink response: a role for the GABA-B receptor?

In well-trained animals, infusion of the GABA-B agonist baclofen into the cerebellar interpositus nucleus and overlying cortex abolished the conditioned response (CR) with no effect on the unconditioned response (UR) with doses at or above 5.0 mM. Infusion of the GABA-B antagonist CGP 5584-5A alone had no effect on the CR or UR. However, administration of 5 mM baclofen soon after infusion of CGP 5584-5A (15 min) resulted in no reduction of percent CR and only partial reduction of CR amplitude. Naive animals given interpositus infusions of baclofen during training showed no learning, yet learned normally in postinfusion training. The distribution of (radiolabelled) baclofen was localized and remained within the cerebellum. The results presented here are consistent with a growing body of literature supporting the hypothesis that the memory trace for eyeblink conditioning is formed and stored in the cerebellum and may involve GABAergic mechanisms.

Animals↗
PubMed1997

The chromosomal organization of the Plasmodium falciparum var gene family is conserved.

The var gene family of Plasmodium falciparum encodes the protein PfEMP1 which is located on the surface of infected erythrocytes and is the receptor that mediates binding to ligands on endothelial cells. This family of proteins is responsible for antigenic variation and differences in binding phenotype to ligands such as CD36 and ICAM1. We have compared the organization of the var gene family in three in vitro cloned lines of P. falciparum and show that most var genes are located in the subtelomeric region of each chromosome closely linked to the repetitive sequence rep20. While most chromosomes possess var genes in the subtelomeric region, in each in vitro cloned line there are some chromosomes that have deleted subtelomeric repetitive regions which include var genes. Comparison of the location of var genes in a field isolate showed that it does not have any detectable subtelomeric deletions as all chromosomes contain var genes and rep20 sequences. We have detected three chromosomes (4, 7 and 12) that contain var gene loci in more stable central regions and the position of these genes on chromosome 4 in the cloned lines analysed is conserved. The location of most of the var gene family in the subtelomeric region of the genome of P. falciparum has important implications for the generation of antigenic diversity of the PfEMP1 protein.

Animals↗
PubMed1997

Body image and psychological sequelae of silicone breast explantation: preliminary findings.

Twenty-two breast explantation (implant removal) and 20 cholecystectomy patients were assessed preoperatively and postoperatively and compared with 20 nonsurgical control subjects on several body-image measures, depression, self-esteem, and self-reported health status. Explantation patients had higher breast anxiety and upper torso dissatisfaction than either control group and levels were unaffected by implant removal. The discrepancy between self-rated ideal and current breast size increased substantially after implant removal for the explantation group, but did not change for controls. Overall appearance satisfaction level and positive appearance-related cognitions decreased as a function of surgery for explantation patients, but remained unchanged in cholecystectomy and nonsurgical controls. Depression levels were elevated in explantation patients and did not change as a function of surgery; self-reported health status level improved for the explantation group, but levels still remained below those of both control groups after explantation. Therapeutic indications for the elevated depression levels and unique body-image issues that patients undergoing explantation experience are discussed.

Anxiety↗
PubMed1997

Electrotransformation of Lactobacillus plantarum using linearized plasmid DNA.

Evidence is presented that linearized plasmid DNA is capable of electrotransforming Lactobacillus plantarum at a frequency 500-fold lower than with the covalently closed circular molecule. When the linearized plasmid was religated prior to transformation the transformation efficiency was < 10-fold higher, suggesting that open circular plasmid was only slightly more efficient in the transformation of Lact. plantarum than linear DNA. This observation has implications for direct cloning into this species since the high background transformation frequency produced by the linear DNA could potentially obscure the recovery of clones. Nevertheless, using positive selection for enhanced chloramphenicol resistance, cloned fragments of Lact. helveticus DNA were obtained using the shuttle vector pGKV110.

Lactobacillus↗
PubMed1996

The var genes of Plasmodium falciparum are located in the subtelomeric region of most chromosomes.

PfEMP1, a Plasmodium falciparum-encoded protein on the surface of infected erythrocytes is a ligand that mediates binding to receptors on endothelial cells. The PfEMP1 protein, which is encoded by the large var gene family, shows antigenic variation and changes in binding phenotype associated with alterations in antigenicity. We have constructed a yeast artificial chromosome contig of chromosome 12 from P. falciparum and show that var genes are arranged in four clusters; two lie amongst repetitive subtelomeric sequences and two occur in the more conserved central region. Analysis of parasite chromosomes by pulsed field gel electrophoresis (PFGE) demonstrates that most contain var genes and two-dimensional PFGE has shown that var genes are located at chromosome ends interspersed amongst repetitive sequences present in the subtelomeric complex. Analysis of a var gene located in the subtelomeric region of chromosome 12 has shown that it has close homologues at the opposite end of the chromosome and in the subtelomeric region of two other chromosomes. This suggests that recombination between heterologous chromosomes has occurred in the subtelomeric regions of these chromosomes. The subtelomeric location of var genes dispersed amongst repetitive sequences has important implications for generation of antigenic variants and novel cytoadherent specificities of this protein.

Animals↗
PubMed1996

Explanations of body image disturbance: a test of maturational status, negative verbal commentary, social comparison, and sociocultural hypotheses.

OBJECTIVE: A number of hypotheses have been offered to explain the development and/or maintenance of body image disturbance. In this study, four factors which have been hypothesized to lead to body image problems were tested: maturational status (early physical development), negative verbal commentary (a history of being teased regarding physical appearance), behavioral social comparison, and awareness/internalization of sociocultural pressures. METHODS: One hundred sixty-two college females completed measures designed to index these four influences. Predictors were regressed onto multiple measures of body image and two indices of eating disturbance. RESULTS: Even with self-esteem and level of obesity removed as influences, social comparison and societal factors were significant predictors of body dissatisfaction and eating disturbance. Negative verbal commentary also explained a small part of the variance, however, maturational status did not contribute uniquely in any analysis. DISCUSSION: The findings offer further support for emerging theories of body image and eating disturbance.

Adolescent↗
PubMed1996

Current status of the Plasmodium falciparum genome project.

The Plasmodium falciparum Genome Project is a collaborative effort by many laboratories that will provide detailed molecular information about the parasite, which may be used for developing practical control measures. Initial goals are to prepare an electronically indexed clone bank containing partially sequenced clones representing up to 80% of the parasite's genes and to prepare an ordered set of overlapping clones spanning each of the parasite's 14 chromosomes. Currently, clones of genomic DNA, prepared as yeast artificial chromosomes, are arranged into contigs covering approximately 70% of the genome of parasite clone 3D7, gene sequence tags are available from more than contigs covering approximately 70% of the genome of parasite clone 3D7, gene sequence tags are available from more than 20% of the parasite's genes, and approximately 5% of the parasite's genes are tentatively identified from similarity searches of entries in the international sequence databases. A total of > 0.5 Mb of P. falciparum sequence tag data is available. The gene sequence tags are presently being used to complete YAC contig assembly and localize the cloned genes to positions on the physical map in preparation for sequencing the genome. Routes of access to project information and services are described.

Animals↗
PubMed1996

Characterization of a proteinaceous antimicrobial produced by Lactobacillus helveticus CNRZ450.

An antimicrobial substance which resembles a bacteriocin was identified in culture supernatant fluids of Lactobacillus helveticus strain CNRZ450. The bacteriocin was active against a narrow range of strains from closely related species of homofermentative lactobacilli. Its mode of action appeared to be bacteriostatic. Partial purification of the bacteriocin suggested that it was a complex protein with a mol. wt of between 30 and 50 kDa, although there is some evidence that the polypeptide monomer has a mol. wt of around 17 kDa. There was no evidence indicating an extrachromosomal location for its genetic determinant. PCR generated an amplicon from total DNA from strain CNRZ450 using primers based on the helJ gene sequence. A fragment showing homology to this amplicon was located in an EcoRI digest of total DNA from strain CNRZ450. The pattern obtained was different from that obtained with the helveticin J producer strain NCFB481. It is possible, therefore, that the antimicrobial from strain CNRZ450 is related to helveticin J at the DNA sequence level although the physical properties of the two antimicrobials reveal several differences.

Bacteriocins↗
PubMed1995

Development and validation of the Sociocultural Attitudes Towards Appearance Questionnaire.

The Sociocultural Attitudes Towards Appearance Questionnaire (SATAQ) was developed to assess women's recognition and acceptance of societally sanctioned standards of appearance. In Study 1, factor analyses revealed two clearcut factors: awareness/acknowledgment of a societal emphasis on appearance and an internalization/acceptance of these standards. These findings were cross-validated in Study 2, resulting in a six-item Awareness subscale (alpha = .71) and an eight-item Internalization subscale (alpha = .88). Study 3 obtained good convergence between both scales and multiple indices of body image and eating disturbance. Regression analyses indicated that both factors accounted for unique variance associated with body image and eating dysfunction, however, internalization of standards was a stronger predictor of disturbance. The SATAQ should prove useful for researchers and clinicians interested in body image and eating disorders.

Adolescent↗
PubMed1995

Development of body image, eating disturbance, and general psychological functioning in female adolescents: covariance structure modeling and longitudinal investigations.

OBJECTIVE: Covariance structure modeling (CSM) and longitudinal analyses were used to identify a possible causal sequence for factors that might lead to the development of body image and eating disturbance in adolescent females. METHOD: In Study 1, subjects were measured for level of obesity, perceived weight status, maturational timing, history of being teased about weight/size, body image, eating disturbance, and global psychological functioning. Study 2 was a systematic replication of Study 1 using different indices of body image and a more comprehensive assessment of eating disturbance. In Study 3, subjects from Study 1 were reassessed at a 3-year follow-up. RESULTS: The findings from Study 1 indicated that level of obesity and perceived weight, but not maturational timing, had a directional influence on the other variables. In addition, teasing history was significantly related to the development of body image and eating disturbance. CSM and path analyses with Studies 2 and 3 data generally replicated and extended the results from Study 1. DISCUSSION: These findings offer important insights into possible causal sequences for the development of body image and eating disturbance.

Adaptation, Psychological↗