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Abstract
A transgenic mouse insertional mutant displayed the phenotype of altered cranial morphology with sex-linked cleft palate. We have cloned the disrupted genomic X-linked locus and report the identification of the mCASK gene. The gene is transcribed to produce two messages of 4.5 and 9.5 kb expressed during development and in adult tissues, particularly the brain. We describe the isolation of two differentially spliced mouse cDNAs from the locus (mCASK-A and mCASK-B). The mCASK-B cDNA probably represents the full-length product of the 4.5-kb transcript. The identical N-termini of the predicted encoded proteins (mCASK-A and -B) are highly homologous to Ca2+/calmodulin-dependent protein kinase II, while the deduced C-terminus of mCASK-B is highly homologous to a family of multidomain proteins containing a guanylate kinase motif, the MAGUK proteins. mCASK-B is a new member of an emerging family of genes in which the encoded proteins combine these domains, termed here, the CAMGUKs, including rat CASK, Caenorhabditis elegans lin-2, and Drosophila caki/camguk. The CAMGUKs are likely to be effectors in signal transduction as regulatory partners of transmembrane molecules, modulated by calcium and nucleotides. The transgene in this mutant mouse line integrated into an intron that bisects the encoded calmodulin-binding domain, a potentially important regulatory domain of the predicted protein, generating hybrid transcripts.
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O'Brien SJ, Pagnani MJ, Fealy S, McGlynn SR, Wilson JB. The active compression test: a new and effective test for diagnosing labral tears and acromioclavicular joint abnormality. Am J Sports Med 1998; 26:610-3. [PMID: 9784804 DOI: 10.1177/03635465980260050201] [Citation(s) in RCA: 329] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Labral tears and acromioclavicular joint abnormalities were differentiated on physical examination using a new diagnostic test. The standing patient forward flexed the arm to 90 degrees with the elbow in full extension and then adducted the arm 10 degrees to 15 degrees medial to the sagittal plane of the body and internally rotated it so that the thumb pointed downward. The examiner, standing behind the patient, applied a uniform downward force to the arm. With the arm in the same position, the palm was then fully supinated and the maneuver was repeated. The test was considered positive if pain was elicited during the first maneuver, and was reduced or eliminated with the second. Pain localized to the acromioclavicular joint or "on top" was diagnostic of acromioclavicular joint abnormality, whereas pain or painful clicking described as "inside" the shoulder was considered indicative of labral abnormality. A prospective study was performed on 318 patients to determine the sensitivity, specificity, and positive and negative predictive values of the test. Fifty-three of 56 patients whose preoperative examinations indicated a labral tear had confirmed labral tears that were repaired at surgery. Fifty-five of 62 patients who had pain in the acromioclavicular joint and whose preoperative examinations indicated abnormalities in the joint had positive clinical, operative, or radiographic evidence of acromioclavicular injury. There were no false-negative results in either group.
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Caldwell RG, Wilson JB, Anderson SJ, Longnecker R. Epstein-Barr virus LMP2A drives B cell development and survival in the absence of normal B cell receptor signals. Immunity 1998; 9:405-11. [PMID: 9768760 DOI: 10.1016/s1074-7613(00)80623-8] [Citation(s) in RCA: 405] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Epstein-Barr virus (EBV) establishes a persistent latent infection in peripheral B lymphocytes in humans and is associated with a variety of malignancies and proliferative disorders. Latent membrane protein 2A (LMP2A) is one of only two viral proteins expressed in latently infected B lymphocytes in vivo. LMP2A blocks B cell receptor (BCR) signal transduction in vitro by binding the Syk and Lyn protein tyrosine kinases. To analyze the significance of LMP2A expression in vivo, transgenic mice with B cell lineage expression of LMP2A were generated. LMP2A expression results in the bypass of normal B lymphocyte developmental checkpoints allowing immunoglobulin-negative cells to colonize peripheral lymphoid organs, indicating that LMP2A possesses a constitutive signaling activity in nontransformed cells.
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MESH Headings
- Animals
- Animals, Genetically Modified
- B-Lymphocytes/cytology
- B-Lymphocytes/virology
- Bone Marrow Cells/cytology
- Bone Marrow Cells/drug effects
- Bone Marrow Cells/immunology
- Cell Differentiation
- Cell Survival
- Cells, Cultured
- Gene Rearrangement, B-Lymphocyte, Heavy Chain/drug effects
- Gene Rearrangement, B-Lymphocyte, Heavy Chain/physiology
- Genes, RAG-1/physiology
- Herpesvirus 4, Human/chemistry
- Herpesvirus 4, Human/immunology
- Interleukin-7/pharmacology
- Lymphocyte Activation/drug effects
- Mice
- Mice, Inbred C57BL
- Mice, Transgenic
- Receptors, Antigen, B-Cell/physiology
- Signal Transduction
- Transgenes/physiology
- Viral Matrix Proteins/genetics
- Viral Matrix Proteins/physiology
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Truett GE, Walker JA, Wilson JB, Redmann SM, Tulley RT, Eckardt GR, Plastow G, Lefevre M. ELISA detection of restriction site polymorphisms in the pig ryanodine receptor locus. Mamm Genome 1998; 9:629-32. [PMID: 9680382 DOI: 10.1007/s003359900834] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
We compare two strategies for ELISA detection of restriction site polymorphisms (EDRSP) that are suitable for high-throughput genotyping of the pig ryanodine receptor point mutation (RYR1(hal)). In both procedures, target DNA is amplified by PCR with one primer that is 5' biotinylated and a second primer that is 5' fluoresceinylated. PCR products are captured in duplicate wells on a streptavidin-coated, 96-well plate. The duplicates may be treated in two ways. In a single restriction enzyme assay, one duplicate is exposed to a restriction enzyme that cuts one allele specifically, and the second duplicate is exposed to no restriction enzyme. In a dual restriction enzyme assay, the second replicate is exposed to a second restriction enzyme that cuts the alternate allele specifically. Thereafter, the two procedures are similar; anti-fluorescein antibodies conjugated to peroxidase are allowed to bind to the fluoresceinylated ends, the plate is washed, and a substrate is converted to a colored end product. The ratio of the absorbances in the two wells is used to classify subjects by genotype. When the dual restriction enzyme assay is run, three genotype groups are easily distinguishable. When the single restriction enzyme assay is run, heterozygotes generate values that may overlap with those of the homozygotes that are not cut by the restriction enzyme. Dual restriction enzyme assays are more accurate than single restriction enzyme assays; however, single restriction enzyme assays are sufficient for identifying pigs that carry RYR1(hal).
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Michel P, Wilson JB, Martin SW, Clarke RC, McEwen SA, Gyles CL. A descriptive study of verocytotoxigenic Escherichia coli (VTEC) cases reported in Ontario, 1990-1994. CANADIAN JOURNAL OF PUBLIC HEALTH = REVUE CANADIENNE DE SANTE PUBLIQUE 1998; 89:253-7. [PMID: 9735519 PMCID: PMC6990236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Characteristics of VTEC cases identified through routine surveillance in Ontario between 1990 and 1994 are described. Information was extracted from the Reportable Disease Information System (RDIS) of Ontario and was evaluated for its completeness and internal validity. A total of 2,441 VTEC cases were identified for the five-year study period corresponding to an average annual rate of 4.8 cases per 100,000. Sixteen deaths were recorded. Bloody diarrhea was reported for 546 patients (40%) and was the most frequently reported symptom. For most cases, the home was recorded as the likely risk setting (36%). Food was incriminated as the source of infection for more than 36% of cases. Nine (69%) of the thirteen data fields compulsory for transmission to the Ontario Ministry of Health had less than 10% of combined missing and unspecified values. Fields describing risk factors had greater than 56% of entries missing or unspecified.
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Rahn K, Renwick SA, Johnson RP, Wilson JB, Clarke RC, Alves D, McEwen SA, Lior H, Spika J. Follow-up study of verocytotoxigenic Escherichia coli infection in dairy farm families. J Infect Dis 1998; 177:1139-40. [PMID: 9535003 DOI: 10.1086/517394] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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Smith KA, Kruth S, Hammermueller J, Gyles C, Wilson JB. A case-control study of verocytotoxigenic Escherichia coli infection in cats with diarrhea. CANADIAN JOURNAL OF VETERINARY RESEARCH = REVUE CANADIENNE DE RECHERCHE VETERINAIRE 1998; 62:87-92. [PMID: 9553706 PMCID: PMC1189453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The objectives of this study were to determine the prevalence of enteric verocytotoxigenic E. coli (VTEC) infection in a population of cats in Ontario, and to determine whether an association exists between the presence of VTEC and feline diarrhea. Fecal samples from 179 cats, representing 113 cats with diarrhea and 66 cats with normal feces, were cultured for E. coli. The fecal cultures were screened for verocytotoxin activity with a Vero cell assay. Confirmation of the presence of verocytotoxin (VT) genes was done with polymerase chain reaction (PCR) amplification; the frequency of occurrence of the genes for generic VT, VT1, and VT2 was determined. VTEC-positive samples were defined as those that demonstrated cytotoxicity on the Vero cell assay and yielded E. coli possessing one or more of the VT genes. All VTEC-positive isolates were serotyped. The overall prevalence of enteric VTEC infection in the cats was 12.3% (22/179). Statistical analysis of the case-control data showed no significant association between VTEC infection and diarrheal illness. The majority of the cats with VT-positive E. coli were positive for the presence of the generic VT, rather than for VT1 or VT2; it is therefore possible that a novel verocytotoxin gene may exist in E. coli isolated from cats. Eight VTEC strains were identified by serotyping; 4 of these serotypes have previously been isolated from humans, and 2 from cattle, suggesting that cats may be capable of acting as reservoirs for human and bovine VTEC serotypes.
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Wilson JB, Renwick SA, Clarke RC, Rahn K, Alves D, Johnson RP, Ellis AG, McEwen SA, Karmali MA, Lior H, Spika J. Risk factors for infection with verocytotoxigenic Escherichia coli in cattle on Ontario dairy farms. Prev Vet Med 1998; 34:227-36. [PMID: 9604270 DOI: 10.1016/s0167-5877(97)00010-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Risk factors for prevalent infection with verocytotoxigenic Escherichia coli (VTEC) were studied in a random sample of 886 cows and 592 calves under 3 months of age on 80 randomly selected dairy farms in southern Ontario. Fecal-culture supernatants from each animal were screened for verocytotoxicity using a Vero cell assay (VCA) and for verocytotoxin (VT) genes by a polymerase chain reaction (PCR) procedure. Up to 20 F. colt isolates from positive samples were tested for VT production using VCA and PCR. VTEC isolates were serotyped. Farm managers were interviewed using a standardized questionnaire to obtain information on farm- and individual animal-level management practices and characteristics. There was a significant (P < 0.001) positive association between age of calves and their VTEC infection status, and calves were significantly more likely to be infected than cows. The proportion of calves infected on the farm was positively associated with both the use of regular pails for feeding calves (as opposed to nipple bottles or nipple pails) and bringing new animals into the herd in the previous year.
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Jackson SG, Goodbrand RB, Johnson RP, Odorico VG, Alves D, Rahn K, Wilson JB, Welch MK, Khakhria R. Escherichia coli O157:H7 diarrhoea associated with well water and infected cattle on an Ontario farm. Epidemiol Infect 1998; 120:17-20. [PMID: 9528813 PMCID: PMC2809344 DOI: 10.1017/s0950268897008479] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
A 16-month old female child living on an Ontario dairy farm was taken to hospital suffering from bloody diarrhoea. Escherichia coli O157:H7 was isolated from her stool. Initial tests of well water samples were negative for E. coli by standard methods but culture of selected coliform colonies on sorbitol-MacConkey agar led to isolation of E. coli O157:H7. E. coli O157:H7 was also isolated from 63% of cattle on the farm. The E. coli O157:H7 isolates from the child, the water and the cattle were phage type 14, produced verotoxins 1 and 2, and were highly related on analysis by pulsed field gel electrophoresis. The child did not have known direct contact with the cattle and did not consume unpasteurized milk. Hydrogeological investigation revealed the design and location of the well would allow manure-contaminated surface water to flow into the well. This investigation demonstrates that cattle farm well water is a potential source of E. coli O157:H7 which may not be identified by standard screening for E. coli in water.
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Wilson JB, Collison AH, Richardson D, Kwofie G, Senah KA, Tinkorang EK. The maternity waiting home concept: the Nsawam, Ghana experience. The Accra PMM Team. Int J Gynaecol Obstet 1997; 59 Suppl 2:S165-72. [PMID: 9389628 DOI: 10.1016/s0020-7292(97)00162-8] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
PRELIMINARY STUDIES Focus group discussions with community members in Nsawam District, Ghana, identified poor roads, scarce transport and exorbitant fees for emergency transport as barriers to reaching the district hospital for treatment of an obstetric complication. INTERVENTIONS To minimize delay in the event of a complication, a maternity waiting home (MWH) was established in Nsawam in 1994. One ward of an abandoned hospital was renovated and furnished for this purpose. The objective was to encourage women at high risk of obstetric complications to move to the MWH so they could be transferred to the hospital when labor began. RESULTS Of 25 women referred to the MWH by health personnel over 12 months, only one complied, for one night. Focus group discussions with community members and hospital staff later revealed that cost and hardship of staying away from home, absence of health personnel, distance from hospital, desolate surroundings and lack of perceived need were reasons for poor utilization. COSTS The intervention cost approximately US $10,500, shared approximately equally between the project and government. The main government contribution was the building. CONCLUSIONS It is important to consult potential users not only to identify problems, but also to identify appropriate solutions. Careful 'market research' should be done before launching interventions.
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Senah KA, Richardson D, Kwofie G, Wilson JB, Collison AH, Tinkorang EK. From abandoned warehouse to life-saving facility, Pakro, Ghana. The Accra PMM Team. Int J Gynaecol Obstet 1997; 59 Suppl 2:S91-7. [PMID: 9389618 DOI: 10.1016/s0020-7292(97)00152-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
PRELIMINARY STUDIES Focus group discussions in Akwapim South District, Ghana, highlighted a lack of accessible health facilities as an important factor contributing to maternal deaths. INTERVENTIONS In 1991, a health center was established by rennovating an abandoned warehouse. The center was equipped with beds, a refrigerator, a safe water supply, drugs and supplies. With the posting of a community health nurse from the Ministry of Health (MOH), it began functioning as a maternal and child health/family planning clinic. A senior nurse-midwife was posted in 1992 and obstetric services were offered. Starting in 1994, community interventions focused on reducing the delay in seeking care. RESULTS An average of nine women with major obstetric complications were seen each 12-month period between 1992 and 1995. Many minor complications and non-obstetric ailments were also treated. COSTS The material costs of establishing the health center amounted to US $12,550: 47% came from the community, 43% came from non-governmental organizations (NGOs), 7% from PMM and 3% from MOH. The costs of staff salaries were paid by MOH. CONCLUSIONS It is possible to mobilize communities, government and NGOs to help provide emergency obstetric services. If emergency obstetric services are available, women will use them, even before the launching of community information and education campaigns.
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Rahn K, Renwick SA, Johnson RP, Wilson JB, Clarke RC, Alves D, McEwen S, Lior H, Spika J. Persistence of Escherichia coli O157:H7 in dairy cattle and the dairy farm environment. Epidemiol Infect 1997; 119:251-9. [PMID: 9363025 PMCID: PMC2808848 DOI: 10.1017/s0950268897007929] [Citation(s) in RCA: 99] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The persistence of Escherichia coli O157:H7 in cattle and the farm environment was investigated on eight Ontario dairy farms positive for E. coli O157:H7 in a longitudinal study commenced one year previously. Faecal samples from cows, calves, humans, cats, rodents, wild birds, a composite fly sample and numerous composite and individual environmental samples were cultured and tested for verotoxin-producing E. coli (VTEC). VTEC isolates were serotyped and E. coli O157:H7 isolates were phage typed. E. coli O157:H7 phage type 34 was isolated from one calf on each of two farms. The same phage type had been isolated on one of these farms 12 months earlier. Most E. coli O157:H7-positive animals and farms became culture-negative within 2 and 3 months, respectively. E. coli O157:H7 was not isolated from any environmental samples, although evidence of VTEC was found in composite samples from calf feeders (19.1%), calf barn surfaces (18%), cow feeders (14.9%), flies (12.5%), cow barn surfaces (11.3%), and individual milk filters (12.5%). VTEC belonging to 21 non-O157 serotypes were isolated from 24 cows (8.2%), 21 calves (18.3%), 2 cow feeder samples (3.0%), and 1 calf feeder sample (4.8%). Shedding of E. coli O157:H7 by infected dairy cattle appears to be transient and persistence of E. coli O157:H7 was not demonstrated from the farm environment sites tested.
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LeClere FB, Wilson JB. Smoking behavior of recent mothers, 18-44 years of age, before and after pregnancy: United States, 1990. ADVANCE DATA 1997:1-11. [PMID: 10182807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
OBJECTIVE This report presents a comprehensive review of data on the smoking behaviors of women with a recent birth from the 1990 National Health Interview Survey. Data on current and lifetime smoking status and smoking behaviors before and after learning of pregnancy are presented. Selected demographic characteristics of women--including age, race, education, and family income--are also presented. METHODS Data presented in this report are from the 1990 National Health Interview Survey on Health Promotion and Disease Prevention (NHIS-HPDP). Questions on pregnancy and smoking were administered as part of this supplement to women 18-44 years of age who either had a live birth in the 5 years preceding the interview, or who were pregnant at the time of the interview. These analyses were limited to women with a live birth in the 5 years preceding the 1990 NHIS who were not currently pregnant. RESULTS Of 13,674,000 women with a recent live birth, about 39 percent had ever smoked, 25 percent smoked in the year before they became pregnant, and 15 percent smoked during their most recent pregnancy. Women who smoked prior to learning of their pregnancy were most likely to be moderate smokers, white women, never married, and of lower income. Women who smoked after learning of their pregnancy were most likely to be light smokers, representing a shift in smoking behaviors after learning of pregnancy. Nearly 23 percent of women reported that they stopped smoking altogether after learning of their pregnancy. CONCLUSIONS These findings are consistent with data from other sources and provide support for recently observed trends in smoking and pregnancy. A majority of women who had ever smoked continued to smoke throughout pregnancy. Although many women altered their smoking behaviors, only about one quarter of women reported that they stopped smoking entirely. Public health service messages must continue to encourage women to stop smoking entirely during pregnancy to maximize the health benefits to their infants.
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Rahn K, Wilson JB, McFadden KA, Read SC, Ellis AG, Renwick SA, Clarke RC, Johnson RP. Comparison of Vero cell assay and PCR as indicators of the presence of verocytotoxigenic Escherichia coli in bovine and human fecal samples. Appl Environ Microbiol 1996; 62:4314-7. [PMID: 8953703 PMCID: PMC168258 DOI: 10.1128/aem.62.12.4314-4317.1996] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Comparisons were made between Vero cell assay (VCA) and PCR as indicators for the detection of verocytotoxigenic Escherichia coli (VTEC; also known as Shiga-like toxin-producing E. coli) and as predictors of VTEC isolation from bovine and human fecal samples. Fecal samples were collected as part of a survey on the prevalence of VTEC on dairy farms in southern Ontario (J. B. Wilson et al., J. Infect. Dis., 174:1021-1027, 1996). A total of 2,655 samples were examined by VCA and PCR, 2,153 originating from cattle and 502 originating from humans. Overall, 36.2% of the samples were positive in the VCA and 38.7% were positive by PCR. Of the VCA-positive samples screened, 41.6% yielded a VTEC isolate. For both human and bovine samples, a significant positive association between PCR result and VCA titer (P = 0.0001) was found. In addition, there was a significant positive association between the PCR result and VTEC isolation from VCA-positive samples for cattle (odds ratio = 9.1, P < 0.0001). For bovine samples positive in the VCA, VCA titer was significantly associated with the probability of obtaining a VTEC isolate. Agreement between VCA and PCR was good for both bovine and human samples (kappa = 0.69 and 0.64, respectively). The sensitivity and specificity of the PCR with respect to the VCA for bovine samples were 82.0 and 86.5%, respectively, and those for human samples were 59.3 and 98.1%, respectively. Although correlation between VCA and PCR results was not absolute, when used in conjunction, these tests complemented one another as predictors of VTEC isolation.
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Wilson JB, Clarke RC, Renwick SA, Rahn K, Johnson RP, Karmali MA, Lior H, Alves D, Gyles CL, Sandhu KS, McEwen SA, Spika JS. Vero cytotoxigenic Escherichia coli infection in dairy farm families. J Infect Dis 1996; 174:1021-7. [PMID: 8896504 DOI: 10.1093/infdis/174.5.1021] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Fecal samples from 335 dairy farm residents and 1458 cattle on 80 farms were tested for Vero cytotoxin (VT)-producing Escherichia coli (VTEC). Residents were also tested for antibodies to VT1 and O157 lipopolysaccharide (LPS). Residents and cattle on farms with VTEC-positive persons or E. coli O157:H7-positive cattle were retested. Twenty-one persons (6.3%) on 16 farms (20.8%) and 46% of cattle on 100% of the farms had VTEC in fecal samples. Human VTEC isolates included E. coli O157:H7 and 8 other serotypes, 4 of which were present in cattle on the same farms. More persons had antibodies to VT1 (41%) than to O157 LPS (12.5%). Seropositivity to O157 LPS was associated with isolation of E. coli O157:H7 on the farm (P = .022). Human VTEC infection was negatively associated with age (P < .05) and was not associated with clinical illness. Many dairy farm residents experience subclinical immunizing VTEC infections at a young age, which frequently involve non-O157 VTEC found in cattle.
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Wilson JB, Bell JL, Levine AJ. Expression of Epstein-Barr virus nuclear antigen-1 induces B cell neoplasia in transgenic mice. EMBO J 1996; 15:3117-26. [PMID: 8670812 PMCID: PMC450254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
The Epstein-Barr virus (EBV) nuclear antigen-1 (EBNA-1) is a pleiotropic protein which has been characterized extensively both biochemically and functionally. It is the only one of the identified latent protein-encoding genes to be consistently expressed in viral-associated endemic Burkitt's lymphoma cells. As such, it is the only candidate viral protein to possibly perform a maintenance function in the tumour pathology. Despite this, no oncogenic activity has been attributed to the protein in tissue culture assays. The experiments described here were initiated to explore the activity of the protein in B cells in vivo. EBNA-1 transgenic mice were generated with transgene expression directed to the B cell compartment using the mouse Ig heavy chain intron enhancer. Transgene expression was demonstrated in the lymphoid tissues of mice of two independent lines. Transgenic positive mice of both lines succumb to B cell lymphoma. The B cell tumours are monoclonal, frequently of follicular centre cell origin and remarkably similar to those induced by transgenic c-myc expression. These results demonstrate that EBNA-1 is oncogenic in vivo and suggest that the gene product may play a direct role in the pathogenesis of Burkitt's lymphoma and possibly other EBV-associated malignancies.
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Rodriguez Romero WE, Castillo M, Chaves MA, Saenz GF, Gu LH, Wilson JB, Baysal E, Smetanina NS, Leonova JY, Huisman TH. Hb Costa Rica or alpha 2 beta 2 77(EF1)His --> Arg: the first example of a somatic cell mutation in a globin gene. Hum Genet 1996; 97:829-33. [PMID: 8641705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
We have identified a minor hemoglobin component (approximately 5%) in the blood of a healthy Costa Rican female, but not in her mother and two brothers (father not studied), that has an His --> Arg replacement at position beta 77 (Hb Costa Rica). No other amino acid replacements were observed and no beta- or gamma-chain-like peptides were present. Hb Costa Rica has abnormal stability. Sequence analyses of numerous polymerase chain reaction (PCR)-amplified segments of DNA that contain exon 2 of the beta gene failed to identify a CAC --> CGC (His --> Arg) mutation. The same was the case when cDNA was sequenced, indicating that a beta-Costa Rica-mRNA could not be detected with this procedure. Gene mapping of genomic DNA with Bg/II, BamHI, and HindIII gave normal fragments only and with the same intensity as observed for the fragments of a normal control. The quantities of the beta chain variants Hb J-Iran and Hb Fukuyama with related mutations at beta 77 vary between 30% and 45% in heterozygotes, whereas that of Hb F-Kennestone with the same His --> Arg mutation but in the G gamma-globin gene, is a high 40%-45% (as percentage of total G gamma) in a heterozygous newborn. These different observations exclude a heterozygosity of the A --> G mutation at codon beta 77, as well as a deletion comparable to that of Hbs Lepore or Kenya, or a beta-globin gene duplication, and point to a nontraditional inheritance of Hb Costa Rica. Allele-specific amplification of cDNA with appropriate primers identified the presence of a low level of mutated mRNA in the reticulocytes of the patient, which was confirmed by dotblot analysis of the same material with 32P-labeled probes. Comparable amplification products were not observed in genomic DNA. The A --> G mutation apparently occurred in a somatic cell at a relatively early stage in the development of the hematopoietic cell system, and Hb Costa Rica accumulated through rapid cell divisions in patchy areas in the bone marrow (somatic mosaicism). An unequal distribution of Hb Costa Rica over the red cells supports this possibility.
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McFarlane M, Wilson JB. A model for the mechanism of precise integration of a microinjected transgene. Transgenic Res 1996; 5:171-7. [PMID: 8673144 DOI: 10.1007/bf01969706] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
A unique transgenic mouse line has undergone transgene integration in a very precise fashion. The phenotype displayed by mice of the line followed the predicted inheritance patterns for X-linked transgene insertion which has been confirmed. In order to investigate the mechanism of integration the DNA sequence of the transgene and cellular junctions have been determined. A comparison between wild type and transgenic mutant sequences at the site of insertion revealed that there was no loss or rearrangement of cellular DNA upon integration of the transgene. The cellular sequences at the transgene 5' and 3' joins are contiguous in the wild type. The integrant exists as a head to tail tandem dimer with minimal loss of sequence compared with the injected monomer. Analysis of the site of insertion has revealed a 5 bp homology between the 5' end of the transgene and the cellular sequences. In addition, adjacent to the site of insertion within the cellular sequences, there are several sequence motifs implicated in recombination events including a clustering of strong consensus sites of DNA topoisomerase type I and a region of homology to the human minisatellite consensus core sequence, the Escherichia coli Chi site and the meiotic recombination hotspot within the E beta gene of the murine major histocompatibility complex. This clustering of features is likely to have been factorial in the integrity of the insertion event. A model depicting the mechanism of this precise integration is proposed.
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MESH Headings
- Animals
- Base Sequence
- Cleft Palate/genetics
- DNA/genetics
- DNA Topoisomerases, Type I/metabolism
- DNA, Recombinant/genetics
- Epidermis/pathology
- Female
- Gene Conversion
- Genes, Viral
- Herpesvirus 4, Human/genetics
- Humans
- Hyperplasia
- Mice
- Mice, Inbred C57BL
- Mice, Transgenic/genetics
- Microinjections
- Models, Genetic
- Molecular Sequence Data
- Polyomavirus/genetics
- Recombination, Genetic
- Regulatory Sequences, Nucleic Acid
- Sequence Homology, Nucleic Acid
- Transgenes
- Viral Matrix Proteins/biosynthesis
- Viral Matrix Proteins/genetics
- X Chromosome/genetics
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Spitz AM, Velebil P, Koonin LM, Strauss LT, Goodman KA, Wingo P, Wilson JB, Morris L, Marks JS. Pregnancy, abortion, and birth rates among US adolescents--1980, 1985, and 1990. JAMA 1996; 275:989-94. [PMID: 8596256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
OBJECTIVE To analyze pregnancy, abortion, and birth rates among US adolescent girls in 1980, 1985, and 1990. DESIGN Retrospective analysis of trends in data on pregnancies, abortions, and births. POPULATION US adolescent girls aged 13 to 19 years. MAIN OUTCOME MEASURES Pregnancy, abortion, and birth rates (with and without adjustment for sexual experience) among teenaged girls aged 15 to 19 years and girls under 15 years. RESULTS Although pregnancy rates among all teenaged girls 15 to 19 years old remained fairly stable from 1980 to 1985, they increased by 9% during the last half of the decade, totaling 95.9 pregnancies per 1000 teenaged girls 15 to 19 years old by 1990. Because rates of sexual experience increased even faster, pregnancy rates among sexually experienced teens aged 15 to 19 actually declined between 1980 and 1990 by approximately 8%. Abortion rates among these teens remained stable during the 1980s, with 35.8 and 36.0 abortions per 1000 in 1980 and 1990, respectively. As with overall pregnancy rates, abortion rates among these sexually experienced teenaged girls declined during the 1980s. Between 1980 and 1985, birth rates among teenaged girls aged 15 to 19 years declined by 4%, but they increased by 18% during the latter half of the decade, totaling 59.9 births per 1000 in 1990. Among these sexually experienced teenagers, birth rates also declined between 1980 and 1985 and then increased over the next 5 years. In 1990, pregnancies and abortions among girls younger than 15 years accounted for only 3% of all adolescent pregnancies and abortions. However, the number of births among these younger adolescents increased by 15% over the decade. In that age group, trends in pregnancy, abortion and birth rates over the decade were similar to those for older teens. However, during the late 1980s, the abortion rate declined and the pregnancy rate remained stable, resulting in a 26% increase in the birth rate. CONCLUSIONS Despite efforts to reduce adolescent pregnancy in the United States, pregnancy and birth rates for that group continue to be the highest among developed countries. Considering that 95% of adolescent pregnancies are unintended, increased efforts to prevent these pregnancies are warranted.
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Obed SA, Armah JO, Wilson JB. Advanced maternal age and pregnancy. West Afr J Med 1995; 14:198-201. [PMID: 8634223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Advanced maternal age pregnancies are still prevalent due to ignorance and lack of effective contraception. These pregnancies have a poorer maternal and perinatal outcome.
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Lassey AT, Ghosh TS, Wilson JB. Management of difficult intra operative bleeding by abdominal packing: report of four cases. EAST AFRICAN MEDICAL JOURNAL 1995; 72:542-3. [PMID: 7588154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Difficult perioperative bleeding in four obstetric and gynaecology patients was managed with temporising abdominal packs left in place with abdominal closure for 48-72 hours in order to avoid deaths on the operating table when blood loss could not be adequately replaced and hemostasis could not be secured. Abdominal re-opening to remove the packs was undertaken. Three of the patients were eventually discharged home after satisfactory recovery. The fourth died of sepsis three weeks after the fourth re-operation and bilateral internal iliac artery ligation. Abdominal packing thus has a place in the management and salvage of patients with difficult obstetric and gynaecologic perioperative bleeding.
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Martey JO, Elkins TE, Wilson JB, Adadevoh SW, MacVicar J, Sciarra JJ. Innovative community-based postgraduate training for obstetrics and gynecology in west Africa. Obstet Gynecol 1995; 85:1042-6. [PMID: 7770252 DOI: 10.1016/0029-7844(95)00066-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
OBJECTIVE To describe a unique international effort to develop a training program in West Africa that would be of similar quality to any other in the world (but with sensitivity to cross-cultural needs) and would retain physicians in West Africa to improve women's health in that part of the world. METHODS Step-by-step formulation of a program included initial trainee recruitment, the inclusion of foreign guest faculty, and the establishment of institutional libraries. This was followed by a phase of curriculum development, recruitment of West African faculty, and organization of an innovative, community-based fourth year. RESULTS Between ten and 12 postgraduates will have completed the program by January 1996, and will be placed in Ghana. More than 60% of Ghanaian postgraduates have passed the relevant regional examinations, compared with less than 25% of candidates from other countries. Nine Ghanaian specialists have returned to Ghana to become faculty members in the program. Over 20 published peer-reviewed articles have resulted from this program since 1989. The number of residents being trained has increased from three to 28. Seven new residents joined the program in 1994. An early reduction in maternal mortality from 9.9 deaths per 1000 births in 1991 to 4.2 deaths per 1000 births in 1992 was noted when senior postgraduates took over labor and delivery at the teaching hospital in Accra, Ghana, where approximately 10,000 deliveries occur per year. CONCLUSION Specialty training in obstetrics and gynecology that is specifically aimed at meeting the needs of West Africa has been initiated successfully. Long-range success will require support from regional governments and continued long-term commitments from the international community of obstetricians and gynecologists.
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Prchal JT, Adler B, Wilson JB, Baysal E, Qin WB, Molchanova TP, Pobedimskaya DD, Kazanetz EG, Huisman TH. Hb Bibba or alpha 2 136(H19)Leu-->Pro beta 2 in a Caucasian family from Alabama. Hemoglobin 1995; 19:151-64. [PMID: 7558871 DOI: 10.3109/03630269509036935] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Several members of a large Caucasian family who presented with a congenital Heinz body hemolytic anemia were found to be carriers of the unstable Hb Bibba or alpha 2 136(H19)Leu-->Pro beta 2. Identification by protein analysis was hampered by the instability of the variant which complicated its isolation from shipped blood samples. Moreover, the detection of the CTG-->CCG mutation at codon 136 of the alpha 2 gene required the substitution of dGTP by dITP during the DNA sequencing process to prevent the occurrence of secondary structures and compressions in the sequencing gel. The first Hb Bibba heterozygote, characterized in 1968 (1), is believed to be a member of this family. The clinical expression of the disease is surprisingly variable.
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Kazanetz EG, Leonova JY, Wilson JB, McMillan SK, Walbrecht M, de Pablos Gallego JM, Huisman TH. Hb Anamosa or alpha 2(111)(G18)Ala-->Val beta 2 (alpha 2 mutation) and Hb Mulhacen or alpha 2(123)(H6)Ala-->Ser beta 2 (alpha 1 mutation) are two silent, stable variants detected by sequencing of amplified DNA. Hemoglobin 1995; 19:1-6. [PMID: 7615398 DOI: 10.3109/03630269509069724] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
We have identified silent amino acid substitutions in two alpha chain variants present in families from Iowa, USA, and Granada, Spain. Both involve an alanine residue in the core peptide, namely Ala-->Val at position 111 (codon change in the alpha 2 gene; GCC->GTC; Hb Anamosa) and Ala-->Ser at position 123 (codon change in the alpha 1 gene; GCC-->TCC; Hb Mulhacen). The two variants are stable. Sequencing of the amplified alpha 2- and alpha 1-globin genes greatly facilitated the characterization of the two variants.
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Johnson RP, Boag L, Anderson S, Holtslander R, Rahn K, Clarke RC, Renwick SA, Alves D, Wilson JB, Spika J. Brucella abortus serology in cattle naturally infected with Escherichia coli O157.H7. Vet Rec 1994; 135:382-3. [PMID: 7831743 DOI: 10.1136/vr.135.16.382] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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