Ondansetron therapy for uremic pruritus in hemodialysis patients

Pruritus is a distressing symptom affecting up to 90% of dialysis patients. Conventional treatment with antihistamines is often ineffective and may have unacceptable side effects. Serotonin (5-hydroxytryptamine type 3 [5-HT(3)]) is known to enhance pain perception and pruritic symptoms through receptors on sensory nerve endings. Antagonism of 5-HT(3) receptors may be of use in treating uremic pruritus. We randomly assigned 16 hemodialysis patients with persistent pruritus to treatment with the 5-HT(3)-receptor antagonist, ondansetron (8 mg), or placebo three times daily for 2 weeks each in a prospective, placebo-controlled, double-blind crossover study. Patients scored their intensity of pruritus daily on a 0-to-10 visual analogue scale (0 = no pruritus, 10 = maximal pruritus), and daily use of antihistamines as escape medication was recorded. The median daily pruritus score did not change significantly during active or placebo treatment (preondansetron, 5. 3; interquartile range [IQR], 3.4 to 6.3; during ondansetron, 3.9; IQR, 2.7 to 5.0; P = not significant; preplacebo, 3.7; IQR, 3.0 to 4. 6; during placebo, 3.6; IQR, 2.4 to 4.8; P = not significant). The median daily percentage of escape medication use decreased from 21% (IQR, 9 to 61) to 9% (IQR, 0 to 33) with ondansetron (P = not significant) and from 53% (IQR, 0 to 88) to 5% (IQR, 0 to 31) with placebo (P = not significant). There was no difference in predialysis biochemistry test results or dialysis efficacy during treatment phases. Ondansetron does not improve pruritus in hemodialysis patients. Use of antihistamines decreased with both ondansetron and placebo.

Localization of an acromesomelic dysplasia on chromosome 9 by homozygosity mapping

The acromesomelic dysplasias (AMDs) are a group of genetic disorders that primarily affect the middle and distal segments of the extremities. A form of AMD is present on the isolated island of St Helena in the South Atlantic, which has a population of approximately 5500 derived from a number of founder individuals. DNA from four affected individuals and 11 first-degree relatives in four related nuclear families segregating an AMD was collected for gene mapping studies. Six consecutive markers on chromosome 9, spanning an approximately 5 cM region, showed identical homozygosity in all affected individuals, thus identifying a region of homozygosity by descent. Multipoint analysis generated a maximum lod score of Z = 2.85. These data localize the gene for this dysplasia to the pericentromeric region of chromosome 9 where the gene for the Maroteaux form of AMD is situated. The identification of the gene responsible for this disorder may shed further light on the complex processes involved in limb morphogenesis.

Large-scale discovery and genotyping of single-nucleotide polymorphisms in the mouse

Single-nucleotide polymorphisms (SNPs) have been the focus of much attention in human genetics because they are extremely abundant and well-suited for automated large-scale genotyping. Human SNPs, however, are less informative than other types of genetic markers (such as simple-sequence length polymorphisms or microsatellites) and thus more loci are required for mapping traits. SNPs offer similar advantages for experimental genetic organisms such as the mouse, but they entail no loss of informativeness because bi-allelic markers are fully informative in analysing crosses between inbred strains. Here we report a large-scale analysis of SNPs in the mouse genome. We characterized the rate of nucleotide polymorphism in eight mouse strains and identified a collection of 2,848 SNPs located in 1,755 sequence-tagged sites (STSs) using high-density oligonucleotide arrays. Three-quarters of these SNPs have been mapped on the mouse genome, providing a first-generation SNP map of the mouse. We have also developed a multiplex genotyping procedure by which a genome scan can be performed with only six genotyping reactions per animal.

Dyspepsia workload in urban general practice and implications of the British Society of Gastroenterology Dyspepsia guidelines (1996)

AIM

To define the characteristics of patients consulting with active dyspeptic symptoms in urban general practice, and to consider the implications of applying the British Society of Gastroenterology Dyspepsia management guidelines.

DESIGN

Prospective observational study over a period of 12 months.

SETTING

Two multipartner, two-centre general practices in the City of Leeds (UK) with a combined target population of 11 011 registered patients.

SUBJECTS

A total of 340 patients consulting with active dyspeptic symptoms (52% male; mean age 53 years, range 16-89 years).

RESULTS

Of the practice population, 3% consulted with dyspepsia (first-time consulter: 19%; previous consulter not yet investigated: 30%; previously investigated: 51%). Of 168 undiagnosed patients, 43% had upper abdominal pain (dysmotility-like symptoms in 42%), 35% had reflux symptoms, 22% had mixed symptoms, 12% had 'alarm' symptoms and 18% had a history of NSAID use. Patients < 45 years old with simple dyspepsia accounted for 32% of undiagnosed cases. A fifth of the workload was in dealing with undiagnosed dyspeptics over 45 years old. One per cent of the population would require endoscopy if all undiagnosed cases either > 45 years or with complicated dyspepsia were investigated. Of 172 previously investigated patients, 29% had negative tests, 25% had 'minor' findings, and 45% had evidence of acid-peptic disease. Patients with duodenal ulcer disease accounted for 12% of the total workload.

CONCLUSIONS

A knowledge of the characteristics of patients consulting with dyspepsia in primary care should allow the adaptation of guidelines, to ensure advice is relevant to local case mix and compatible with local resources.

Molecular characterization of Irish Salmonella enterica serotype typhimurium: detection of class I integrons and assessment of genetic relationships by DNA amplification fingerprinting

Salmonella enterica is among the principal etiological agents of food-borne illness in humans. Increasing antimicrobial resistance in S. enterica is a cause for worldwide concern. There is concern at present in relation to the increasing incidence of human infection with antimicrobial agent-resistant strains of S. enterica serotype Typhimurium, in particular of phage type DT104. Integrons appear to play an important role in the dissemination of antimicrobial resistance genes in many Enterobacteriaceae including S. enterica. In this study the antimicrobial susceptibilities and phage types of 74 randomly collected strains of S. enterica serotype Typhimurium from the Cork region of southern Ireland, obtained from human, animal (clinical), and food sources, were determined. Each strain was examined for integrons and typed by DNA amplification fingerprinting (DAF). Phage type DT104 predominated (n = 48). Phage types DT104b (n = 3), -193 (n = 9), -195 (n = 6), -208 (n = 3), -204a (n = 2), PT U302 (n = 1), and two nontypeable strains accounted for the remainder. All S. enterica serotype Typhimurium DT104 strains were resistant to ampicillin, chloramphenicol, streptomycin, Sulfonamide Duplex, and tetracycline, and one strain was additionally resistant to trimethoprim. All DT104 strains but one were of a uniform DAF type (designated DAF-I) and showed a uniform pattern of integrons (designated IP-I). The DT104b and PT U302 strains also exhibited the same resistance phenotype, and both had the DAF-I and IP-I patterns. The DAF-I pattern was also observed in a single DT193 strain in which no integrons were detectable. Greater diversity of antibiograms and DAF and IP patterns among non-DT104 phage types was observed. These data indicate a remarkable degree of homogeneity at a molecular level among contemporary isolates of S. enterica serotype Typhimurium DT104 from animal, human, and food sources in this region.

Engineering Deinococcus radiodurans for metal remediation in radioactive mixed waste environments

We have developed a radiation resistant bacterium for the treatment of mixed radioactive wastes containing ionic mercury. The high cost of remediating radioactive waste sites from nuclear weapons production has stimulated the development of bioremediation strategies using Deinococcus radiodurans, the most radiation resistant organism known. As a frequent constituent of these sites is the highly toxic ionic mercury (Hg) (II), we have generated several D. radiodurans strains expressing the cloned Hg (II) resistance gene (merA) from Escherichia coli strain BL308. We designed four different expression vectors for this purpose, and compared the relative advantages of each. The strains were shown to grow in the presence of both radiation and ionic mercury at concentrations well above those found in radioactive waste sites, and to effectively reduce Hg (II) to the less toxic volatile elemental mercury. We also demonstrated that different gene clusters could be used to engineer D. radiodurans for treatment of mixed radioactive wastes by developing a strain to detoxify both mercury and toluene. These expression systems could provide models to guide future D. radiodurans engineering efforts aimed at integrating several remediation functions into a single host.

Specific expansion of protein families in the radioresistant bacterium Deinococcus radiodurans

Computer analysis of the complete genome of Deinococcus radiodurans R1 reveals a number of protein families, which are over-represented in this organism, compared to most other bacteria with known genome sequences. These families include both previously characterized and uncharacterized proteins. Most of the families whose functions are known or could be predicted seem to be related to stress-response and elimination of damage products (cell-cleaning). The two most prominent family expansions are the Nudix (MutT) family of pyrophosphohydrolases and a previously unnoticed family of proteins related to Bacillus subtilis DinB that could possess a metal-dependent enzymatic activity whose exact nature remains to be determined. Several proteins of the expanded families, particularly the Nudix family, are fused to other domains and form multidomain proteins that are so far unique for Deinococcus. The domain composition of some of these proteins indicates that they could be involved in novel DNA-repair pathways. Such unique proteins are good targets for knock-out and gene expression studies, which are aimed to shed light on the unusual features of this interesting bacterium.

Integronlike structures in Campylobacter spp. of human and animal origin

Resistance to antimicrobial agents used to treat severe Campylobacter spp. gastroenteritis is increasing worldwide. We assessed the antimicrobial resistance patterns of Campylobacter spp. isolates of human and animal origin. More than half (n = 32) were resistant to sulphonamide, a feature known to be associated with the presence of integrons. Analysis of these integrons will further our understanding of Campylobacter spp. epidemiology.

Biological markers of risk in nipple aspirate fluid are associated with residual cancer and tumour size

We previously demonstrated that nipple aspirate fluid (NAF) can be obtained from virtually all non-Asian women between the ages of 30 and 72. The focus of this report is to (1) determine the association of candidate markers of breast cancer risk in NAF obtained from fresh mastectomy specimens with residual breast carcinoma, and (2) evaluate the association of the markers with breast tumour progression. Nipple aspiration was performed on 97 specimens. Cytology, DNA index (including % hypertetraploid cells), cell cycle parameters (S phase fraction, % cells in G2/M), prostate-specific antigen (PSA), epidermal growth factor (EGF), testosterone, carcinoembryonic antigen (CEA) and prostaglandin D synthase (PGDS) were evaluated in NAF for their association with (1) residual ductal carcinoma in situ (DCIS) or invasive cancer, and (2) pathologic tumour size. NAF was obtained from 99% (96/97) of specimens. Atypical and malignant NAF cytology were significantly associated with residual DCIS or invasive cancer (P = 0.001) and with larger tumours (P = 0.004). One hundred per cent and 88% of subjects with malignant and atypical NAF cytology, respectively, had residual carcinoma. The percentage of cells in G2/M and DNA index were associated both with risk of residual carcinoma (P = 0.01 for each) and larger tumour size (DNA index, P = 0.03; G2/M, P = 0.05), although neither biomarker improved the ability of NAF cytology, to predict residual breast cancer. Higher DNA index was associated with atypical cytology (P = 0.0001). In summary, atypical and malignant NAF cytology are associated with larger tumour size, and are highly predictive of residual carcinoma after needle or excisional biopsy of the breast.

Risky behaviors among Louisiana youth

The main threats to adolescents' health are the risky behaviors they engage in and the choices they make. There are six health-risk behaviors that adolescents engage in that account for the majority of morbidity and mortality in this age group: alcohol and drug use; tobacco use; risky sexual behaviors; behaviors leading to intentional and unintentional injury; physical inactivity; and unhealthy dietary behaviors. These behaviors also greatly impact academic achievement. Using morbidity and mortality data obtained from the Office of Public Health and survey data, risk behaviors among adolescents in Louisiana are considered. School-based health centers are one successful strategy for comprehensively addressing these behaviors.

Pregnancy and risk of early breast cancer in carriers of BRCA1 and BRCA2

BACKGROUND

Early age at first full-term pregnancy and increasing parity are associated with a reduced risk of breast cancer. However, whether pregnancy decreases the risk of early-onset hereditary breast cancer is unknown. There is concern that pregnancy may increase breast-cancer risk in carriers of BRCA1 and BRCA2 germline mutations. We aimed to establish whether pregnancy is a risk factor for hereditary breast cancer.

METHODS

We did a matched case-control study of breast cancer in women who carry deleterious BRCA1 or BRCA2 mutations. Cases were carriers who developed breast cancer by age 40 years, and controls were carriers of the same age without breast cancer, or who were diagnosed with breast cancer after age 40 years. Women who had undergone preventive mastectomy, hysterectomy, or oophorectomy, or who were diagnosed with ovarian cancer before the age at which breast cancer was diagnosed in the matched case were excluded. Information about pregnancies and pregnancy outcome was derived from a questionnaire completed by women in the course of genetic counselling.

FINDINGS

A higher proportion of cases than controls had had a full term pregnancy (173/236 vs 146/236; odds ratio 1.71 [95% CI 1.13-2.62], p=0.01). The mean number of births was also greater for cases than for controls (1.62 vs 1.38, p=0.04). The risk increased with the number of births and did not diminish with time since last pregnancy. There were no significant differences in age at first birth or age at last birth between cases and controls.

INTERPRETATION

Carriers of the BRCA1 and BRCA2 mutations who have children are significantly more likely to develop breast cancer by age 40 than carriers who are nulliparous. Each pregnancy is associated with an increased cancer risk. An early first pregnancy does not confer protection for carriers of BRCA1 or BRCA2 mutations.

Short repeats and IS elements in the extremely radiation-resistant bacterium Deinococcus radiodurans and comparison to other bacterial species

Computer analysis of the complete genome of Deinococcus radiodurans R1 has shown that the number of insertion sequences (ISs) and small noncoding repeats (SNRs) it contains is very high, and comparable with those of Escherichia coli. IS elements and several families of SNRs are described, together with their possible function in the D. radiodurans genome.

Whole-genome shotgun optical mapping of Deinococcus radiodurans

A whole-genome restriction map of Deinococcus radiodurans, a radiation-resistant bacterium able to survive up to 15,000 grays of ionizing radiation, was constructed without using DNA libraries, the polymerase chain reaction, or electrophoresis. Very large, randomly sheared, genomic DNA fragments were used to construct maps from individual DNA molecules that were assembled into two circular overlapping maps (2.6 and 0.415 megabases), without gaps. A third smaller chromosome (176 kilobases) was identified and characterized. Aberrant nonlinear DNA structures that may define chromosome structure and organization, as well as intermediates in DNA repair, were directly visualized by optical mapping techniques after gamma irradiation.

Ozone-induced acute lung injury: genetic analysis of F(2) mice generated from A/J and C57BL/6J strains

Acute lung injury (or acute respiratory distress syndrome) is a devastating and often lethal condition. This complex disease (trait) may be associated with numerous candidate genes. To discern the major gene(s) controlling mortality from acute lung injury, two inbred mouse strains displaying contrasting survival times to 10 parts/million ozone were identified. A/J (A) mice were sensitive [6.6 +/- 1 (SE) h] and C57BL/6J (B) were resistant (20.6 +/- 1 h). The designation for these phenotypes was 13 h, a point that clearly separated their survival time distributions. Our prior segregation studies suggested that survival time to ozone-induced acute lung injury was a quantitative trait, and genetic analysis identified three linked loci [acute lung injury-1, -2, and -3 (Ali1-3, respectively)]. In this report, acute lung injury in A or B mice was characterized histologically and by measuring lung wet-to-dry weight ratios at death. Ozone produced comparable effects in both strains. To further delineate genetic loci associated with reduced survival, a genomewide scan was performed with F(2) mice generated from the A and B strains. The results strengthen and extend our initial findings and firmly establish that Ali1 on mouse chromosome 11 has significant linkage to this phenotype. Ali3 was suggestive of linkage, supporting previous recombinant inbred analysis, whereas Ali2 showed no linkage. Together, our findings support the fact that several genes, including Ali1 and Ali3, control susceptibility to death after acute lung injury. Identification of these loci should allow a more focused effort to determine the key events leading to mortality after oxidant-induced acute lung injury.

Does postoperative irradiation play a role in the adjuvant therapy of stage T4 colon cancer?

PURPOSE

This study analyzes the long-term outcome of patients with stage T4 colon cancer who receive postoperative irradiation. The purpose of the study is to define the potential role of this modality with current systemic therapies.

PATIENTS AND METHODS

A retrospective analysis was performed of 152 patients undergoing resection of T4 colon cancer followed by moderate- to high-dose postoperative tumor bed irradiation with and without 5-fluorouracil-based chemotherapy. Of the 152 patients, 110 patients (T4N0 or T4N+) were treated adjuvantly, whereas 42 patients received irradiation for the control of gross or microscopic residual local tumor.

RESULTS

For 79 adjuvantly treated patients with stage T4N0 or T4N+ cancer with one lymph node metastasis, the 10-year actuarial rates of local control and recurrence-free survival were 88% and 58%, respectively. Results were less satisfactory for patients with more extensive nodal involvement. The 10-year actuarial rates of local control and recurrence-free survival of 39 patients with T4 tumors complicated by perforation or fistulas were 81% and 53%, respectively. For 42 patients with incompletely resected tumors, the 10-year actuarial recurrence-free survival was 19%.

CONCLUSIONS

In comparison with historical controls, postoperative tumor bed irradiation improves local control for some subsets of patients. In addition to standard 5-fluorouracil-based chemotherapy, adjuvant tumor bed irradiation should be considered when colon cancers invade adjoining structures, when they are complicated by perforation or fistulas, or when they are incompletely excised at the primary site.

A randomized trial of breast cancer risk counseling: the impact on self-reported mammography use

OBJECTIVES

We evaluated the impact of individualized breast cancer risk counseling on mammography use among women at risk for breast cancer.

METHODS

Participants (n = 508) were randomized to the breast cancer risk counseling intervention or a general health education control intervention, and 85% completed follow-up.

RESULTS

In multivariate modeling, a significant group-by-education interaction demonstrated that among less-educated participants, breast cancer risk counseling led to reduced mammography use. There was no intervention effect among the more-educated participants.

CONCLUSIONS

These results suggest that standard breast cancer risk counseling could have an adverse impact on the health behaviors of less-educated women.

Molecular analysis of Pseudomonas aeruginosa: epidemiological investigation of mastitis outbreaks in Irish dairy herds

Pseudomonas aeruginosa is a pathogen in both humans and animals. This bacterium, most often associated with respiratory infections in cystic fibrosis patients, was found to be the causative agent in bovine mastitis outbreaks among 11 Irish dairy herds. Epidemiological findings suggested that the infection was spread to all herds by teat wipes that had been contaminated with this organism. Two molecular-typing strategies were used in an attempt to determine the genomic relationship(s), if any, of the P. aeruginosa strains isolated from the various herds and to verify whether the same strain was responsible for each outbreak. Thirty-six isolates from the mastitis outbreaks were tested and compared to fourteen clinical isolates from Cork University Hospital. With one exception, all outbreak-linked strains produced identical patterns when ribotyped with ClaI and PvuII enzymes. Eight of the clinical isolates gave the same ClaI ribotype pattern as the mastitis-causing strains. However, PvuII proved more discriminatory, with only the outbreak isolates producing identical patterns. Similar results were obtained with RW3A-primed DNA amplification fingerprinting, with all outbreak isolates except one displaying the same fingerprint array. The clinical strains produced several fingerprint patterns, all of which were different from those of the mastitis-causing isolates. Fine-resolution DNA fingerprinting with a fluorescence-labelled RW3A primer also identified a number of low-molecular-weight polymorphisms that would have remained undetected by conventional methods. These data support the view that the same P. aeruginosa strain was responsible for the mastitis outbreaks in all 11 herds.

Salmonella tel-el-kebir and terrapins

OBJECTIVES

An outbreak of Salmonella tel-el-kebir occurring over a 6-month period is described in this report. This is the first outbreak of S. tel-el-kebir in the reported literature.

METHODS

S. tel-el-kebir was isolated from human faecal samples using conventional laboratory methods.

RESULTS

Eight patients had S. tel-el-kebir isolated from faeces. All patients were owners of, or in close contact with, pet terrapins. The terrapins were purchased in the same pet shop, where they were imported from America. The epidemiological link with these pets was confirmed, as S. tel-el-kebir was isolated from cloacal swabs from the terrapins, and from terrapin water. Molecular biology studies using DNA amplification fingerprinting (DAF) gave identical fingerprint patterns for all human and terrapin isolates.

CONCLUSIONS

Salmonellosis associated with exotic pets is a re-emerging disease in the 1990s, and measures to reduce this are discussed.

Exploring family relationships in cancer risk counseling using the genogram

OBJECTIVES

The genogram is a tool that has facilitated counseling in family therapy and social work for many years. It is hypothesized that genograms may also be useful in genetic counseling, because they help the counselor to acquire more objective and consistent information from the client, as well as to incorporate family dynamics and psychosocial issues into the counseling approach.

MATERIALS AND METHODS

A pilot study of genograms used as an adjunct to genetic counseling was performed at Fox Chase Cancer Center's Family Risk Assessment Program. A questionnaire was developed to elicit genograms from 38 women at risk for familial breast and/or ovarian cancer. After standard pedigree expansion, a series of questions was asked about the consultand's relationship with other family members, communication patterns within the family, attitudes toward genetic testing, family reactions to cancer, roles individuals play in the family, and significant historical or anniversary events. Relationships were defined by the consultand as close, very close, conflictual, fused and conflictual, distant, or estranged.

RESULTS

The majority of relationship types reported by 38 individuals was "very close" or "close." Eighty-one % reported having close/very close relationships with their spouses, 83% reported close/very close relationships with their mothers, and 70% reported close/very close relationships with their fathers. The degree of familial cohesion as depicted by the genogram correlates positively with scores obtained on the standardized Social Adjustment Scale Self-Report (P = 0.01).

CONCLUSIONS

Given the family-wide implications of genetic testing, the genogram may offer important guidance in family-targeted interventions.

Human evolutionary psychology and animal behaviour

Homo sapiens is increasingly being studied within the evolutionary (adaptationist, selectionist) framework favoured by animal behaviour researchers. There are various labels for such work, including evolutionary psychology, human behavioural ecology and human sociobiology. Collectively, we call these areas 'human evolutionary psychology' (HEP) because their shared objective is an evolutionary understanding of human information processing and decision making. Sexual selection and sex differences have been especially prominent in recent HEP research, but many other topics have been addressed, including parent-offspring relations, reciprocity and exploitation, foraging strategies and spatial cognition. Many HEP researchers began their scientific careers in animal behaviour, and in many ways, HEP research is scarcely distinguishable from other animal behaviour research. Currently controversial issues in HEP, such as the explanation(s) for observed levels of heritable diversity, the kinds of data needed to test adaptationist hypotheses, and the characterization of a species-typical 'environment of evolutionary adaptedness', are issues in animal behaviour as well. What gives HEP a distinct methodological flavour is that the research animal can talk, an ability that has both advantages and pitfalls for researchers. The proper use of self-reports and other verbal data in HEP might usefully become a subject of future research in its own right. Copyright 1999 The Association for the Study of Animal Behaviour.

Prostate cancer risk assessment program. A model for the early detection of prostate cancer

Prostate cancer is the most common form of cancer (except skin cancer) in men. Several factors have been associated with an increased risk for prostate cancer, including age, ethnicity, family history, lifestyle, and environmental exposures. Recognition of the importance of the interaction of these factors in prostate cancer has led to an interest in their evaluation as a model both for studying genetic susceptibility patterns and for studying and providing educational tools and preventive interventions. One such model has been developed at Fox Chase Cancer Center. Critical to the implementation of the model has been the establishment of the Prostate Cancer Risk Registry (PCRR) and Prostate Cancer Risk Assessment Program (PRAP). Together, they serve as a unique resource for investigating the interaction between environmental factors and genetic susceptibility patterns; exploring the early, premalignant biological markers of prostate cancer; and prospectively assessing the quality of life (QOL) of men at risk. In addition, PRAP facilitates the evaluation of models for prostate cancer risk counseling and screening in the community. This paper describes this model for early detection and risk reduction, along with preliminary data from its first two study aims. The program is particularly relevant in view of the wealth of genetic information emerging from the Human Genome Project.