Electromyographic differences of the gluteus maximus, gluteus medius, biceps femoris, and vastus lateralis between the barbell hip thrust and barbell glute bridge

Hip extensor muscles are critical to sport performance as events requiring sprinting and forceful landings are highly dependent on these muscles. Despite biomechanical differences between the barbell hip thrust (BHT) and the barbell glute bridge (BGB), both are biomechanically efficient ways to load this musculature for training purposes. Research investigating the differences in muscular activity between the BHT and BGB has yet been conducted. The aim of this study was to investigate, through surface electromyography, if one exercise is more optimal than the other in producing greater muscle activation for specific hip extensor muscles. Ten male participants completed a two-part study protocol. Results revealed the BHT elicited significantly greater muscle activity within the vastus lateralis for peak and mean outcomes; however, the BGB elicited significantly greater muscle activity in the upper and lower gluteus maximus for peak and mean outcomes and mean outcome in the gluteus medius. Current findings suggest, the BGB is, at minimum, a superior substitute for the BHT for eliciting a larger magnitude of activity in the gluteus maximus. Future studies between the two exercises are warranted to discern which produces greater hypertrophy and whether adaption of the BHT or BGB transfers more optimally to sport performance.

Incidental germline variants in 1000 advanced cancers on a prospective somatic genomic profiling protocol

BACKGROUND

Next-generation sequencing in cancer research may reveal germline variants of clinical significance. We report patient preferences for return of results and the prevalence of incidental pathogenic germline variants (PGVs).

PATIENTS AND METHODS

Targeted exome sequencing of 202 genes was carried out in 1000 advanced cancers using tumor and normal DNA in a research laboratory. Pathogenic variants in 18 genes, recommended for return by The American College of Medical Genetics and Genomics, as well as PALB2, were considered actionable. Patient preferences of return of incidental germline results were collected. Return of results was initiated with genetic counseling and repeat CLIA testing.

RESULTS

Of the 1000 patients who underwent sequencing, 43 had likely PGVs: APC (1), BRCA1 (11), BRCA2 (10), TP53 (10), MSH2 (1), MSH6 (4), PALB2 (2), PTEN (2), TSC2 (1), and RB1 (1). Twenty (47%) of 43 variants were previously known based on clinical genetic testing. Of the 1167 patients who consented for a germline testing protocol, 1157 (99%) desired to be informed of incidental results. Twenty-three previously unrecognized mutations identified in the research environment were confirmed with an orthogonal CLIA platform. All patients approached decided to proceed with formal genetic counseling; in all cases where formal genetic testing was carried out, the germline variant of concern validated with clinical genetic testing.

CONCLUSIONS

In this series, 2.3% patients had previously unrecognized pathogenic germline mutations in 19 cancer-related genes. Thus, genomic sequencing must be accompanied by a plan for return of germline results, in partnership with genetic counseling.

Clinical factors that affect breast cancer risk reduction decisions in high risk women tested for the BRCA1/2 genetic mutation

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Background: Women with an increased risk for breast cancer have many risk reduction options including: prophylactic mastectomy, prophylactic oophorectomy, chemoprevention, and screening. Women without breast cancer make such decisions in a purely preventive setting and factors that affect their decisions are unclear. Method: We performed an IRB approved retrospective review of the medical records on women who underwent BRCA testing. We evaluated the women without a history of breast cancer to assess clinical characteristics and their relation to decision making. The risk reduction categories analyzed were: prophylactic mastectomy, prophylactic oophorectomy, tamoxifen, increased surveillance with MRI, and standard screening (clinical breast exam and mammography). Patient characteristics were tabulated by clinical decision group and the chi-square test or Fisher’s exact test was used. Results: From 2001, 627 patients have undergone genetic testing. 202 of these women did not have a history of breast cancer among whom 58 were mutation carriers. Most patients chose standard screening (47%) or increased surveillance (38%). 4% chose tamoxifen, 7% chose prophylactic mastectomy, 3% chose both prophylactic mastectomy and oophorectomy, and 5% chose oophorectomy. The tamoxifen group was too small to do further analysis. Increased surveillance did not show any significant association with any of the clinical factors that we evaluated. The majority of women who chose standard screening had a personal history of ovarian cancer (p<0.0001) and had no family history of ovarian cancer (p=0.02). Prophylactic surgeries were significantly associated with positive BRCA status (p=0.01). Women with a family history of ovarian cancer tended to have prophylactic surgery (p=0.02). Women who had DCIS or a breast biopsy tended to have prophylactic mastectomies (p=0.0001 and p<0.001 respectively). Conclusion: In breast cancer free women, BRCA status, family history of ovarian cancer, DCIS, and breast biopsy were associated with prophylactic surgeries. Having ovarian cancer or no family history of ovarian cancer were associated with standard screening. We are performing a questionnaire study to determine the reasons behind these women’s choices.

No significant financial relationships to disclose.

Familial gastrointestinal stromal tumor with homo-/hemizygous kit exon 11 deletion: Genotypic, histopathologic, radiographic, and therapeutic findings

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Background: Germ-line mutations in the kit receptor tyrosine kinase gene have been described in families with a propensity to develop gastrointestinal stromal tumor (GIST). We describe a large kindred with multiple individuals with GIST and describe the genotype, clinical presentation, radiographic imaging, surgical findings, imatinib-sensitivity, and histopathologic appearance. Patients and Methods: A large kindred with multiple GISTs were identified after the proband patient was referred to our institution. The history of each affected and unaffected family member was obtained in person or via telephone. A medical questionnaire was sent to family members and appropriate medical records, tumor tissue and radiographic imaging was obtained. Histopathologic specimens from four of the family members with GIST was obtained, the diagnosis confirmed and three specimens were used to sequence kit exon 9, 11, 13, 15 and 17. Results: Fifteen members were identified in this family with histopathologic diagnosis of GIST or probable GIST. Surgical findings revealed multiple tumors arising from the submucosa of the small intestine. Histopathology revealed microscopic proliferation of the myenteric plexus with areas of microscopic tumor nodularity. Four patients in this kindred were treated with imatinib and had radiographic and clinical evidence of therapeutic benefit. A deletion of codon 579 in exon 11 of the kit gene was identified in tumor and normal tissue of this family. Evaluation of one GIST revealed loss of heterozygosity in kit exon 11 suggesting a homozygous mutation or loss of the wild-type locus. Conclusion: This study describes a kindred with a propensity to develop GIST in association with hyperpigmentation and melanocytic nevi, but not dysphagia. The germline deletion of codon 579 appears to confer proliferation and nodularity of the myenteric plexus, synchronous tumors at presentation, a metastatic phenotype, and in vivo sensitivivity to imatinib therapy.

No significant financial relationships to disclose.

HIV testing in the setting of inpatient acute substance abuse treatment

We examined patients' attitudes toward HIV testing in the setting of acute substance abuse treatment and determined the prevalence of offering routine on-site testing for human immunodeficiency virus (HIV) in inpatient state-funded detoxification centers in New England. Voluntary questionnaires were administered to patients (N = 66 respondents) at the only two state-funded inpatient drug detoxification treatment centers in Rhode Island, and a telephone survey of all state-funded inpatient detoxification facilities across the New England area was conducted. In New England, 17/38 (44.7%) of all state-funded inpatient detoxification facilities didnot routinely offer on-site HIV testing to clients. Of participants, 97% responded positively to the question, "Do you think HIV testing should be available to patients in drug detoxification facilities such as this one?" There were 89% who reported that they would cope "about the same" or "better" with receiving a positive HIV test result while in detoxification treatment versus elsewhere. The greatest number of participants ranked the Orasure HIV test, an assay for HIV-1 transmucosal antibody, as the test they would most prefer while in drug treatment. However, 59% of patients responded that the type of test offered would not make a difference in whether they chose testing. Most patients indicated that they would want to see a physician within a few days of a positive diagnosis of HIV infection. Despite the controversy surrounding the provision of HIV testing to patients in inpatient acute substance abuse treatment, HIV testing is desired among these patients provided that HIV clinical care is readily available.

In vitro insecticidal effects of fipronil and beta-cyfluthrin on larvae of the blowfly Lucilia sericata

The insecticidal effects of the phenylpyrazole, fipronil, and a pyrethroid, beta-cyfluthrin, on larvae of the blowfly Lucilia sericata were determined in laboratory assays. When first stage larvae of L. sericata were reared on homogenized pig liver which had been treated with known amounts of test compounds, both fipronil and beta-cyfluthrin induced significant levels of mortality compared to acetone and water controls. However, fipronil was approximately 10 times more toxic than beta-cyfluthrin to L. sericata larvae following ingestion. Beta-cyfluthrin had little effect on mortality until concentrations of approximately 0.5 ppm were reached. In contrast, fipronil effected L. sericata mortality at a concentration of 0.05 ppm and 100% mortality was reached by 0.5 ppm. The lethal concentration (LC50) value for beta-cyfluthrin was 1.56 ppm as compared to 0.14 ppm for fipronil. Following contact of first and third stage larvae with cloth impregnated with known amounts of test compound, the mortality profiles of fipronil and beta-cyfluthrin were similar. At short contact times, the LC50 values for fipronil were lower than those for beta-cyfluthrin. However, at the highest contact time evaluated for the first stage larvae, 300 s, there was a reversal in this trend. The results suggest that the phenylpyrazole fipronil may represent a new potential insecticide for development against blowfly strike of sheep.

TP53 mutation and haplotype analysis of two large African American families

Two large apparently unrelated African American families with a high incidence of breast cancer and other tumors characteristic of Li-Fraumeni breast sarcoma cancer family syndrome were studied. Mutation screening revealed that in both families the affected members carried a germline mutation of the TP53 gene at codon 133 (ATG--> ACG, M133T). In order to determine whether an ancestral haplotype was shared by these two families, polymorphic markers within and flanking the TP53 gene were studied. Haplotype analysis using five markers revealed an identical haplotype shared by the two families. Loss of heterozygosity at the TP53 locus in the probands' tumor tissues from each family was observed; in each case, the retained allele carried the common haplotype. The frequency of this haplotype in the general African American population is <0.003. This unique haplotype, combined with the rare TP53 mutation, suggests that these African American families share a common ancestry. This finding suggests that other African Americans may be carriers of this mutation and thus may be at risk of early-onset breast cancer or other cancers characteristic of the Li-Fraumeni breast sarcoma cancer family syndrome. The finding of recurring mutations in African Americans may facilitate carrier screening and identification in this population.

Obstacles to needle exchange participation in Rhode Island

OBJECTIVE

This study explores obstacles to participation in needle exchange programs (NEPs) among injection drug users (IDUs) in the state of Rhode Island, U.S.A.

METHODS

A written questionnaire was administered at two Rhode Island drug detoxification sites in 1998.

RESULTS

488 self-administered surveys were completed, 226 (46.3%) respondents had injected drugs in the past 6 months. 62.1% reported sharing syringes in the past 6 months, and each syringe was used a mean of 10.7 times. Major obstacles to NEP participation were a lack of awareness of the program (25.6%), inconvenient location or hours (15.9%), and fear of identification and/or police harassment (12.2%). Non-white race was a significant predictor of being unaware of the NEP (p = .01) and not participating in the NEP (p = .03). 13.1% of IDUs who used the NEP were referred to the detoxification program by the NEP. Among all IDUs surveyed, 51.0% had participated in a NEP.

CONCLUSIONS

NEPs are important in reducing the spread of bloodborne pathogens among IDUs and are effective referral sources for drug treatment. Surveys of IDUs at sites other than NEPs, such as detoxification facilities, can identify obstacles to the use of NEPs.

Confirmation of FWT1 as a Wilms' tumour susceptibility gene and phenotypic characteristics of Wilms' tumour attributable to FWT1

A susceptibility gene for Wilms' tumour (WT), designated FWT1, was previously mapped to chromosome 17q12-q21 by linkage analysis of a single family. We now confirm the existence of this gene by analysis of additional cases in the original family (3-point LOD score=5.69), and by detecting strong evidence of linkage to this region in an unrelated pedigree with seven cases of WT (3-point LOD score=2.56). Analysis of 11 smaller WT families confirms that there is genetic heterogeneity in familial WT, as three families exhibit strong evidence against linkage to FWT1. One of these was subsequently found to have a predisposing WT1 mutation. However, the other two families show evidence against both FWT1 and WT1, suggesting that at least one further familial WT gene exists. Analysis of the phenotype of 16 WT cases from the families linked to FWT1 demonstrates that they present at a significantly older age and a significantly later stage than both sporadic WT and the six cases from two families unlinked to either FWT1 or WT1. The results confirm the role of FWT1 in susceptibility to WT, provide strong evidence for genetic heterogeneity in familial WT and suggest there are phenotypic differences between familial WT due to FWT1, familial WT due to other genes and non-familial WT.

De novo germline mutations of the p53 gene in young children with sarcomas

Germline p53 mutations are associated with cancer predisposition in Li-Fraumeni families as well as in individuals with component tumors of the syndrome. In the majority of cases these mutations have been shown to be inherited rather than de novo. We screened 59 children with primary bone or soft tissue sarcomas. Germline p53 mutations were identified in 2 patients. Interestingly, analysis revealed that both mutations were de novo. Although the frequency of germline p53 mutations in primary pediatric sarcoma patients is low, there is evidence for the importance of considering pediatric patients for testing for de novo mutations.

False aneurysm--a complication following an inversion ankle sprain: a case report

Sprains of the lateral ligamentous structures of the ankle joint as a result of inversion are common and frequently result in pain. In most cases, the pain is related to soft-tissue injury and the associated hemorrhage and swelling. This case report describes the complication of posttraumatic false aneurysm of the peroneal artery following an inversion ankle sprain in a 22-year-old athlete, a complication which should be added to the differential diagnosis as a rare, but important possibility. Emphasis of the case report is placed on the rehabilitation of the patient following medical intervention.

The effect of faecally excreted ivermectin and fenbendazole on the insect colonisation of cattle dung following the oral administration of sustained-release boluses

The effects of faecal drug residues following the administration of anthelmintics in the form of sustained-release boluses, on dung-colonising Coleoptera and Diptera are reported. In blind field trials, pats of standard weight and size were prepared from the dung of cattle treated with an ivermectin (Ivomec SR Bolus, MSD Agvet) or a fenbendazole (Panacur Bolus, Hoechst) sustained-release bolus, and from a third control group of cattle that received no treatment. Pats were recovered after 7, 14, 21 and 42 days in the field and searched for invertebrates. There were no differences in the numbers of adult beetles found in the pats from the three treatment groups. Pats made from the dung of ivermectin-treated animals contained no larval Diptera Cyclorrhapha and significantly fewer larval Scarabaeidae than pats made from the dung of the other two groups. Furthermore, larval Scarabaeidae in the ivermectin pats were inhibited in their development. The pats from fenbendazole-treated animals contained similar numbers of larval Scarabaeidae and Diptera to the pats from untreated animals throughout the trial. At 42 days, the solid matter of the control and fenbendazole-containing cow pats were reduced to a crumbling, granular texture, while the pats from the ivermectin-treated animals were solid and compacted. Pitfall trapping, using traps baited with dung from the three groups, showed no significant difference between the numbers of adult Scarabaeidae attracted, though a trend towards higher numbers attracted to the dung of both anthelmintic-treated groups was evident. The results provide evidence of the toxic effects of excreted ivermectin on key dung-colonising families of insects, and show that fenbendazole lacks such toxic effects.

Pleuropulmonary blastoma: a marker for familial disease

OBJECTIVE

To catalog and evaluate patterns of disease in families of children with pleuropulmonary blastoma (PPB).

METHODS

Data have been collected since 1988 on 45 children with PPB and their families. All pathologic materials were centrally reviewed. Preliminary molecular genetic analyses were performed when possible.

RESULTS

In 12 of 45 patients, an association was found between PPB and other dysplasias, neoplasias, or malignancies in the patients with or in their young relatives. The diseases found to be associated with PPB include other cases of PPB, pulmonary cysts, cystic nephromas, sarcomas, medulloblastomas, thyroid dysplasias and neoplasias, malignant germ cell tumors, Hodgkin disease, leukemia, and Langerhans cell histiocytosis. Abnormalities of the p53 tumor suppressor gene, Wilms tumor suppressor gene (WT1), and the putative second genetic locus for Wilms tumor (WT2) were not found in preliminary investigations.

CONCLUSIONS

The occurrence of PPB appears to herald a constitutional and heritable predisposition to dysplastic or neoplastic disease in approximately 25% of cases. All patients with PPB and their families should be investigated carefully. Further research of this new family cancer syndrome may provide insight into the genetic basis of these diseases.

Met proto-oncogene product is overexpressed in tumors of p53-deficient mice and tumors of Li-Fraumeni patients

Inappropriate expression of Met, the receptor for hepatocyte growth factor/scatter factor, has been implicated in sarcomagenesis via an autocrine mechanism. Sarcomas occur at high frequency in individuals with Li-Fraumeni syndrome as well as in p53-deficient mice. Here we show that these tumors express high levels of Met. Moreover, late passage fibroblast cell lines established from p53-deficient animals overexpress Met and can be tumorigenic in athymic nude mice, suggesting that progression occurs in vitro. The tumor explants display increased hepatocyte growth factor/scatter factor expression and Met turnover, indicating that autocrine Met activation contributes to tumor progression. Thus, the loss of wild-type p53 appears to greatly enhance the opportunity for inappropriate Met expression. Loss of p53 function does not by itself cause transformation, but inappropriate Met expression may be an important factor in sarcomagenesis.

Structural analysis of the human nov proto-oncogene and expression in Wilms tumor

We have cloned and sequenced the nov gene (novH) which is the homolog of the chicken nov proto-oncogene overexpressed in avian nephroblastomas. The novH gene is highly conserved and encodes a putative IGF-binding protein similar to that of chicken. We report that relative to autologous normal kidney expression of novH is elevated in Wilms tumors containing predominantly stromal elements and is inversely correlated in these tumors to the expression of WT1. Our results suggest that the regulation of IGFII expression by WT1 and increase of novH in Wilms tumors might be interrelated and represent a key element in tumor development in human.

Concordance between parental origin of chromosome 13q loss and chromosome 6p duplication in sporadic retinoblastoma

Two hypotheses are capable of explaining nonrandom loss of one parent's alleles at tumor suppressor loci in sporadic cases of several pediatric cancers, including retinoblastoma--namely, preferential germ-line mutation or chromosome imprinting. We have examined 74 cases of sporadic retinoblastoma for tumors in which at least two genetic events--loss of heterozygosity for chromosome 13q markers and formation of an isochromosome 6p--have occurred. Sixteen cases were found to contain both events. In 13 of 16 such tumors, the chromosomes 13q that were lost and chromosomes 6p that were duplicated are derived from the same parent. These data may be explained within the framework of the genome imprinting model but are not predicted by preferential germ-line mutation.

Forty-year experience with second malignancies after treatment of childhood cancer: analysis of outcome following the development of the second malignancy

As the cure rate for childhood malignancies increases, the number of patients at risk for development of second malignancies also increases. Due to the potentially long remaining life span, long-term follow-up is difficult and patients are often at risk after presumptive cures. Some authors believe that cure rates for second malignancies are similar to cure rates for primary malignancies. We reviewed the records of 162 patients seen at our institution who had developed a second malignancy after treatment for childhood cancer. Presentation, age at diagnosis, tumor histology, extent of tumor, treatment (including radiotherapy with dosage when available, and chemotherapy) plus outcome were recorded. Mean age at diagnosis of the primary malignancy was 10.3 years. The most common primary malignancy was Hodgkin's disease (33) followed by soft tissue sarcoma (28), retinoblastoma (20), bone tumor (17), central nervous system (CNS) tumor (13), leukemia (8), Wilms' tumor (7), non-Hodgkin's lymphoma (6), neuroblastoma (5), thyroid neoplasm (5), and others (20). The average interval between diagnosis of the first and second malignancy was 10.8 years. These second tumors carried a high mortality. Only 56 patients have no evidence of disease. Five patients are known to be alive with disease and 92 patients have expired due to their second malignancy. Disease status in 8 patients is unknown. The most common second malignancy was osteosarcoma (35) followed by soft tissue sarcoma (24), breast cancer (15), leukemia (14), thyroid carcinoma (14), CNS tumors (12), melanoma (8), nonmelanomatous skin cancer (8), lymphoma (5), and others (27).(ABSTRACT TRUNCATED AT 250 WORDS)

Overview: the impact of avermectins on pastureland ecology

Avermectins, a relatively new class of broad spectrum pesticides, are used widely to control livestock parasites. Following treatment, avermectins are eliminated in the livestock faeces where they also have a wide range of harmful affects upon certain characteristic insects that breed in dung, few of which are pests, and many of which are beneficial. The effects range from acute toxicity in larvae and adults, through disruption of metamorphosis, to interference with reproduction. Different methods of drug administration lead to different concentrations of drug residues in the faeces, which in turn influence the responses of non-target organisms. Higher Diptera are particularly sensitive to drug residues and show a wide range of responses from death of larvae to developmental abnormalities in the adults. Larvae and immature adults of Coleoptera show some mortality in the dung of recently treated animals, while delayed effects upon reproduction and physiology have been observed in adults feeding on dung at longer post-treatment times. Although the impact of lethal doses has been described in some species, the effects of sub-lethal doses have hardly been recognised at the present time. Correlated with the deleterious effect upon dung-breeding insects, a retardation in the rate of loss of biomass of dung pats from avermectin-treated cattle has been observed following the various forms of drug administration. Differences in methodology, inappropriate statistics, and/or extremes of climatic conditions prevailing at the time of testing, explain the results of those studies where such delays have not been observed. It is short-sighted to consider only dung dispersal in relation to avermectin usage, a practice that overlooks the impact on the insects themselves and their diverse roles in pastureland ecology.

Research recommendations

Delegates met on the final morning to identify areas where information is lacking and to highlight priority areas for future research. Five principal topics were discussed: veterinary usage, methodology, invertebrate populations, agricultural impact and integrated pest management.

Some effects of ivermectin on the yellow dung fly, Scatophaga stercoraria

Ivermectin was added to fresh cattle dung at a range of concentrations based on those found in faeces of livestock treated by injection. Newly hatched larvae of Scatophaga stercoraria were then reared in the dung as a bioassay. The EC50 values for 24 h and 48 h larval mortalities were 0.051 ppm and 0.036 ppm (wet wt.) respectively. When the dung concentration was 0.015 ppm, 50% of the insects failed to pupariate and a level of 0.001 ppm prevented adult emergence in 50% of the insects. When batches of larvae were reared in dung containing as little as 0.0005 ppm, the emerging adults showed developmental abnormalities in wing morphology. In addition to the significantly higher level of fluctuating asymmetry, 23% of the treated insects developed new veins and new cells in the wings. The observations are discussed in relation to previous work and attention is drawn to the practice of failing to observe the full impact of sublethal effects, which can be as serious as those of acute toxicity.

Sn-chlorin e6 antibacterial immunoconjugates. An in vitro and in vivo analysis

Monoclonal antibody-Sn-chlorin e6 immunoconjugates were prepared by the site-selective covalent modification of the monoclonal oligosaccharide moiety. By carefully controlling the reaction conditions and introducing triethanolamine groups as axial ligands of the Sn moiety, conjugates with in vivo biodistribution properties similar to underivatized IgG were prepared. By varying the reaction conditions, conjugates were reproducibly prepared with a range of photosensitizer to mAb molar ratios from 1.6 to 10. Based on a competitive inhibition radioimmunoassay, conjugates prepared by this method showed selectivity and binding affinity comparable to the unmodified antibody. The immunoconjugates had only slightly lower singlet oxygen yields than that observed with the Sn-chlorin e6 precursor indicating that negligible aggregation or structural modification of the chromophores occurred during the synthesis process. In vitro cell killing experiments demonstrated that all conjugates possessed significant cytotoxic activity. Biodistribution studies in mice showed that conjugates prepared with axial ligands had significant serum retention 24 h after injection while conjugates prepared without the triethanolamine ligand were much more rapidly cleared. In vivo specificity was demonstrated using rats infected with Fisher immunotype I P. aeruginosa at a site in the left posterior thigh muscle. Target to background ratios exceeded 60 at 120 h after conjugate injection of the specific immunoconjugate, compared to a ratio of only 6 for a non-specific mouse IgG conjugate. Biodistribution patterns at 120 h post injection indicate that the conjugates were both biologically active and structurally intact.

Genetic characterization of the APC locus involved in familial adenomatous polyposis

Familial adenomatous polyposis is a rare disease inherited in a Mendelian dominant fashion. It is characterized by the occurrence of more than 100 adenomatous polyps in the large bowels of affected individuals. The genetic defect responsible for adenomatous polyposis resides at a locus called APC which has been localized to the long arm of human chromosome 5. In this study, the APC locus was mapped with respect to 11 markers known to map to this chromosomal segment. Linkage of APC to four of these markers had been previously reported. Three additional markers are shown here to be linked to APC. By multipoint analysis, the APC locus maps to an interval bounded by D5S49 and D5S58. The refined map of the APC locus and the new markers described here improve the informativeness and accuracy of the presymptomatic diagnosis of familial adenomatous polyposis.

The chemical control of livestock parasites: Problems and alternatives

Over 200 classes of chemical compounds are currently in use for the treatment of livestock parasites. Here Les Strong and Richard Wall review some of the problems arising from the total reliance on chemical control and consider some of the alternative methods that might be given more thought and application.

Perioral blisters in a bug-biting baby

We report peri-oral blistering caused by biting a bug, Palomena prasina, commonly found in the U.K. This is just one of a number of insects commonly found in the U.K. which produce chemicals for defensive purposes that may injure human skin. Contact with insects should, therefore, be considered as a cause of blistering eruptions, even in Britain, especially in the young who are more likely to handle insects.

Environmental consequences of treating cattle with the antiparasitic drug ivermectin

Ivermectin (22,23-dihydroavermectin B1) is a recently discovered, persistent, broad-spectrum, antiparasitic drug of unpredecented potency which is now routinely administered to cattle, horses, sheep and pigs in many countries. In cattle, it is an efficient control for parasitic gastrointestinal and respiratory tract nematodes, warble fly, mites, lice and ticks. However, most of the ivermectin dose is ultimately eliminated in the faeces of the treated animals where it has been shown to have an insecticidal effect on the larvae of economically important, dung-breeding, haematophagous Diptera. Nevertheless, the effects of excreted ivermectin on the cowpat fauna as a whole and the wider consequences of such effects have not previously been considered. In field trials reported here, the faeces of calves fitted with rumenal boluses delivering ivermectin at 40 micrograms per kg per day, failed to degrade in the normal way and this failure was associated with the absence of dung-degrading insects. Faeces from placebo-treated controls contained a characteristic dung-degrading invertebrate community and were largely degraded within 100 days. These results indicate that the increasing widespread use of ivermectin may have important environmental consequences for pastureland.

Extended haplotypes of chromosome 6 in adult rheumatoid arthritis

In 46 patients with rheumatoid arthritis (RA) the allele C4B*3 occurred in 6 patients, while among 350 normal controls, it occurred 6 times (P less than 0.00002). Among 9 white and 1 black families, each of which had 2 or more members with RA, there were 36 haplotypes associated with RA. An extended haplotype (specific HLA-B, DR, complotype haplotypes in significant linkage disequilibrium) containing C4B*3: HLA-B15, DR4, BF*S, C2*C, C4A*3, C4B*3, was found twice (P less than 0.001) among whites with the disease-associated chromosomes.

Human C4 haplotypes with duplicated C4A or C4B

In the course of study of families for the sixth chromosome markers HLA-A, C, B, D/DR, BF, and C2, the two loci for C4, C4A, and C4B, and glyoxalase I, we encountered five examples of probable duplication of one or the other of the two loci for C4. In one of these, both parents and one sib expressed two different structural genes for C4B, one sib expressed one, and one sib expressed none, suggesting that two C4B alleles were carried on a single haplotype: HLA-A2, B7, DR3, BFS1, C2C, C4A2, C4B1, C4B2, GLO1. In a second case, two siblings inherited C4B*1 and C4B*2 from one parent and C4B*Q0 from the other. This duplication appeared on the chromosome as HLA-AW33, B14, DR1, BFS, C2C, C4A2, C4B1, C4B2, GLO2. In a third, very large family with 3 generations, a duplication of the C4B locus occurred which was followed in 2 generations. In one individual, there were three C4B alleles and two C4A alleles. One of the C4B alleles had a hemolytically active product with electrophoretic mobility near C4B2 and was designated C4B*22. It segregated with C4B1 in the family studied. The complete haplotype was HLA-A11, CW1, BW56, DR5, BFS, C2C, C4A3, C4B22, C4B1, GLO2. In another family with 12 siblings, one parent and eight children expressed two C4A alleles on the haplotype HLA-AW30, BW38, DR1, BFF, C2C, C4A3, C4A2, C4BQ0, GLO1.(ABSTRACT TRUNCATED AT 250 WORDS)

The interrelationship between vesico-ureteric reflux, trigonal abnormalities and a bifid pelvicalyceal collecting system: a family study

3 investigations have been undertaken to study the interrelationship between a bifid pelvicalyceal collecting system, vesico-ureteric reflux and lateral ectopia of the ureteric orifice. Firstly, in 30 families investigated to confirm the familial incidence of bifid and double ureters there were 3 families in which siblings were found with primary reflux. Secondly, reflux was found in 62 of 110 patients investigated with a duplex pelvicalyceal system. Reflux was to the ipsilateral kidney in 48 patients but occurred to the contralateral kidney, unaffected by duplicity, in 14. This high incidence of reflux is related to lateral ectopia of the ureteric orifice which may be either bilateral or unilateral. Thirdly, the incidence of a bifid pelvicalyceal system was determined in the parents and siblings of a series of 32 patients with primary reflux. The results support the hypothesis that primary reflux may be inherited by an autosomal dominant gene of variable penetrance in a manner similar to the inheritance of a duplex urinary tract. Thus there is a direct genetic relationship between primary vesico-ureteric reflux, lateral ectopia of the ureteric orifices and a duplex pelvicalyceal system.

Incontinentia pigmenti (Bloch-Sulzberger syndrome) associated with acute granulocytic leukemia

Incontinentia pigmenti, a syndrome of developmental defects, was found to be associated with acute granulocytic leukemia in a 4-month-old black girl. She has been responsive to antileukemic drugs, and remission has been induced without difficulty after each relapse. Although survival time was expected to be very short because of her age, race, type of leukemia, and initial peripheral leukocyte count at time of diagnosis, she is still alive 35 months after diagnosis of leukemia. One may speculate that the prolonged survival time might be related to the unknown genetic defect.