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J Bowers

Publications and source records attributed to J Bowers.

At least 19 recordsLinked to original sources
PubMed2004

Real-time PCR quantification of Vibrio parahaemolyticus in oysters using an alternative matrix.

This study examined the relationship between levels of total Vibrio parahaemolyticus found in oyster tissues and mantle fluid with the goal of using mantle fluid as a template matrix in a new quantitative real-time PCR assay targeting the thermolabile hemolysin (tlh) gene for the enumeration of total V. parahaemolyticus in oysters. Oysters were collected near Mobile Bay, Ala., in June, July, and September and tested immediately after collection and storage at 26 degrees C for 24 h. Initial experiments using DNA colony hybridization targeting tlh demonstrated that natural V. parahaemolyticus levels in the mantle fluid of individual oysters were strongly correlated (r = 0.85, P < 0.05) with the levels found in their tissues. When known quantities of cultured V. parahaemolyticus cells were added to real-time PCR reactions that contained mantle fluid and oyster tissue matrices separately pooled from multiple oysters, a strong linear correlation was observed between the real-time PCR cycle threshold and the log concentration of cells inoculated into each PCR reaction (mantle fluid: r = 0.98, P < 0.05; and oyster: r = 0.99, P < 0.05). However, the mantle fluid exhibited less inhibition of the PCR amplification than the homogenized oyster tissue. Analysis of natural V. parahaemolyticus populations in mantle fluids using both colony hybridization and real-time PCR demonstrated a significant (P < 0.05) but reduced correlation (r = -0.48) between the two methods. Reductions in the efficiency of the real-time PCR that resulted from low population densities of V. parahaemolyticus and PCR inhibitors present in the mantle fluid of some oysters (with significant oyster-to-oyster variation) contributed to the reduction in correlation between the methods that was observed when testing natural V. parahaemolyticus populations. The V. parahaemolyticus-specific real-time PCR assay used for this study could estimate elevated V. parahaemolyticus levels in oyster mantle fluid within 1 h from sampling time.

Animals↗
PubMed2003

Oyster-to-oyster variability in levels of Vibrio parahaemolyticus.

This study examined the variability in the levels of total and pathogenic Vibrio parahaemolyticus in individual oysters. Twenty oysters were collected on three occasions (in June, July, and September 2001) from a site near Mobile Bay, Ala. Ten of these oysters were tested immediately, and 10 were tested after 24 h of storage at 26 degrees C. Levels of total and pathogenic V. parahaemolyticus were determined by alkaline phosphatase-labeled DNA probe procedures targeting the thermolabile hemolysin and thermostable direct hemolysin genes, respectively. Similar V. parahaemolyticus levels (200 to 2,000 CFU/g) were found in nearly 90% of the oysters (for all sampling occasions) prior to storage. The log-transformed densities (means +/- standard deviations) of V. parahaemolyticus in oysters immediately after harvest were 2.90 +/- 0.91, 2.88 +/- 0.36, and 2.47 +/- 0.26 log10 CFU/g for June, July, and September, respectively. After storage for 24 h at 26 degrees C, the mean V. parahaemolyticus densities increased approximately 13- to 26-fold. Before storage, pathogenic V. parahaemolyticus was detected in 40% (10 to 20 CFU/g) of the oysters collected in June and July but was not detected in any oysters collected in September. After storage, pathogenic V. parahaemolyticus was detected in some oysters at levels of > 100 CFU/g. These data should aid in the development of sampling protocols for oyster monitoring programs and in the determination of exposure distributions associated with raw oyster consumption.

Animals↗
PubMed2002

Growth and survival of Vibrio parahaemolyticus in postharvest American oysters.

Oysters at the retail stage of distribution generally contain greater densities of Vibrio parahaemolyticus than do oysters at harvest. The objective of this study was to determine the effects of postharvest storage at 26 and 3 degrees C on the growth and survival of naturally occurring V. parahaemolyticus in shellstock American oysters (Crassostrea virginica). Oysters were collected monthly from May 1998 through April 1999 from Mobile Bay, Alabama, and their V. parahaemolyticus densities were determined after 0, 5, 10, and 24 h of postharvest storage at 26 degrees C. After 24 h of storage at 26 degrees C, oysters were transferred to a refrigerator at 3 degrees C and analyzed 14 to 17 days later. V. parahaemolyticus numbers were determined by a direct plating method involving an alkaline-phosphatase-labeled DNA probe that targets the species-specific thermolabile hemolysin gene (tlh-AP) to identify suspect isolates. From April to December, when water temperatures at harvest were >20 degrees C, the geometric mean harvest density of V. parahaemolyticus was 130 CFU/g. When water temperatures were <20 degrees C, the geometric mean harvest density was 15 CFU/g. After harvest, V. parahaemolyticus multiplied rapidly in live oysters held at 26 degrees C, showing a 50-fold increase (1.7 log CFU/g) at 10 h and a 790-fold increase (2.9 log CFU/g) at 24 h (April through December). Average V. parahaemolyticus numbers showed a sixfold decrease (0.8 log CFU/g) after approximately 14 days of refrigeration. These results indicate that V. parahaemolyticus can grow rapidly in unrefrigerated oysters.

Animals↗
PubMed2001

MSH-MLH complexes formed at a DNA mismatch are disrupted by the PCNA sliding clamp.

In the yeast Saccharomyces cerevisiae, mismatch repair (MMR) is initiated by the binding of heterodimeric MutS homolog (MSH) complexes to mismatches that include single nucleotide and loop insertion/deletion mispairs. In in vitro experiments, the mismatch binding specificity of the MSH2-MSH6 heterodimer is eliminated if ATP is present. However, addition of the MutL homolog complex MLH1-PMS1 to binding reactions containing MSH2-MSH6, ATP, and mismatched substrate results in the formation of a stable ternary complex. The stability of this complex suggests that it represents an intermediate in MMR that is subsequently acted upon by other MMR factors. In support of this idea, we found that the replication processivity factor proliferating cell nuclear antigen (PCNA), which plays a critical role in MMR at step(s) prior to DNA resynthesis, disrupted preformed ternary complexes. These observations, in conjunction with experiments performed with streptavidin end-blocked mismatch substrates, suggested that PCNA interacts with an MSH-MLH complex formed on DNA mispairs.

Adaptor Proteins, Signal Transducing↗
PubMed2001

Populations of Vibrio parahaemolyticus in retail oysters from Florida using two methods.

Vibrio parahaemolyticus is a naturally occurring estuarine bacterium that is often associated with gastroenteritis in humans following consumption of raw molluscan shellfish. A number of studies have investigated the environmental distribution of V. parahaemolyticus, but little is known about the levels of this organism during distribution of oysters or at the point of consumption. Duplicate samples of shellstock oysters were collected monthly (September 1997 to May 1998) from the same four restaurants and three wholesale seafood markets in the Gainesville, Fla. area and analyzed for total V. parahaemolyticus densities using two methods: a standard MPN method (BAM-MPN) and a new direct plating procedure (direct-VPAP). Both methods employed an alkaline phosphatase-labeled DNA probe (VPAP) targeting the species-specific thermolabile hemolysin (tlh) gene to confirm suspect colonies as V. parahaemolyticus. The highest monthly geometric mean V. parahaemolyticus density was observed in October of 1997 (approximately 3,000/g) with similarly high values during September and November of 1997. From December 1997 to May 1998 mean densities were generally less than 100/g, falling to approximately 10/g in February and March. A strong correlation (r = 0.78) between the direct-VPAP and BAM-MPN methods for determining V. parahaemolyticus densities in market-level oysters was observed. The direct-VPAP method was more rapid and precise while the BAM-MPN was more sensitive and may better recover stressed cells. The utilization of the VPAP probe for identification of V. parahaemolyticus sharply reduced the labor for either method compared to biochemical identification techniques used in earlier V. parahaemolyticus surveys.

Animals↗
PubMed2001

The pitfalls of transthoracic echocardiography. A case of eustachian valve endocarditis.

A case of infective endocarditis involving the vestigial eustachian valve is presented and the available English medical literature is reviewed. Only 5 prior cases have been reported: 4 of those required transesophageal echocardiography for diagnosis, and the other was found at autopsy. This clinical entity is routinely missed on transthoracic echocardiography. Injection drug use is a common predisposing factor, and Staphylococcus aureus is the most commonly identified organism. This report broadens the differential diagnosis of endovascular infections in injection drug users and highlights the importance of transesophageal echocardiography for diagnosis in selected patients.

Adult↗
PubMed2001

Organisational implications of concentration orthopaedic services.

The re-organisation of the acute health services in 1999 is causing many acute trusts to consider the practical implications of concentrating services. This may be in terms of the complete merger of departments at different units or a less radical policy of the alternation of the responsibility for emergency receiving between units. The benefits may include the opportunity to improve the quality of care by providing more specialist services, more attractive working conditions with a larger pool of specialists providing the on-call rota and enhanced opportunity for training. Economic theory indicates that concentration should lead to economies of scale by greater sharing of fixed overhead costs, whilst statistical theory specifies that concentration should produce a relative decline in the variability of demand. This paper examines the effects of concentration on emergency admissions in an orthopaedic department by means of a series of simulation experiments. It examines the potential economies of scale for theatre utilisation and bed usage associated with increasing the volume of non-elective patients. As the volume of patients increases so the relative variability of demand decreases and the relative demand for emergency operating theatre time declines. Concentration could offer savings on theatre time allocated to trauma patients, but the impact on wards is less significant with concentration having a limited effect on the demand for beds.

Bed Occupancy↗
PubMed2000

Analysis of yeast MSH2-MSH6 suggests that the initiation of mismatch repair can be separated into discrete steps.

The yeast MSH2-MSH6 complex is required to repair both base-pair and single base insertion/deletion mismatches. MSH2-MSH6 binds to mismatch substrates and displays an ATPase activity that is modulated by mispairs that are repaired in vivo. To understand early steps in mismatch repair, we analyzed mismatch repair (MMR) defective MSH2-msh6-F337A and MSH2-msh6-340 complexes that contained amino acid substitutions in the MSH6 mismatch recognition domain. While both heterodimers were defective in forming stable complexes with mismatch substrates, only MSH2-msh6-340 bound to homoduplex DNA with an affinity that was similar to that observed for MSH2-MSH6. Additional analyses suggested that stable binding to a mispair is not sufficient to initiate recruitment of downstream repair factors. Previously, we observed that MSH2-MSH6 forms a stable complex with a palindromic insertion mismatch that escapes correction by MMR in vivo. Here we show that this binding is not accompanied by either a modulation in MSH2-MSH6 ATPase activity or an ATP-dependent recruitment of the MLH1-PMS1 complex. Together, these observations suggest that early stages in MMR can be divided into distinct recognition, stable binding, and downstream factor recruitment steps.

Adenosine Triphosphatases↗
PubMed2000

Band-shaped and whorled microcystic dystrophy of the corneal epithelium.

OBJECTIVE: To report the clinical, histopathologic, and electron microscopic features of band-shaped and whorled microcystic corneal epithelial dystrophy. DESIGN: Two interventional case reports. PARTICIPANTS: Two patients, two eyes. INTERVENTION: The involved area of corneal epithelium was scraped from each cornea. RESULTS: Histopathologic examination showed microscopic vacuoles in the epithelial cytoplasm in both cases. Electron microscopic examination revealed mainly empty cytoplasmic vacuoles with scant nonspecific osmophilic material. The process recurred clinically in one patient. Changes in corneal topography are documented in one patient. CONCLUSION: Clinical findings and pathologic studies seem nearly identical to those in the original report. No pattern of systemic disorder or medication use was found. The cause of this condition remains unknown.

Aged↗
PubMed2000

Behavioural treatment (biofeedback) for constipation following hysterectomy.

BACKGROUND: Constipation after hysterectomy has been postulated to be due to pelvic nerve damage, but there may be emotional or reversible physical factors of pathophysiological relevance. The aim of this study was to determine whether such constipation is responsive to behavioural treatment. METHODS: Three groups of patients who had completed a course of biofeedback treatment were compared: women with no history of abdominal or pelvic surgery (n = 25), women for whom a hysterectomy had led to no change in bowel function (n = 27) and women who stated that their constipation was precipitated (n = 18) or severely worsened (n = 8) by hysterectomy. Pretreatment and post-treatment details about bowel function and symptoms were assessed using structured interview, and pretreatment whole-gut transit time and anorectal physiology testing were assessed for prognostic relevance. RESULTS: Follow-up after completing treatment was a median of 28 (range 12-44) months. Forty-eight of 78 patients considered that their constipation had improved with treatment; the proportion in each group was similar (P = 0.73). Biofeedback reduced the need to strain, reduced abdominal pain, improved bowel frequency, and reduced laxative use to a similar degree in all three groups. Thirty-three of 53 patients with slow transit considered there was an improvement, compared with 15 of 22 with measured normal transit. Physiological testing did not predict outcome and did not differ between the three groups. CONCLUSION: The majority of patients complaining of constipation induced or worsened by hysterectomy respond subjectively to behavioural treatment, in a similar proportion to those with idiopathic constipation. In contrast to the widely held view that nerve damage is responsible for symptoms, reversible factors are likely to be important in many patients.

Adult↗
PubMed2000

Tensions used on girths on thoroughbred racehorses.

OBJECTIVE: To determine commonly used girth tensions in Thoroughbred racehorses in the Melbourne metropolitan area. DESIGN: A prospective industry survey. METHODS: Strappers were instructed to tension girths, using the same saddle, under-saddle packing and girth, sufficiently to hold the saddle for racing. These tensions were continuously recorded by an in-line load cell in the girth. Seventeen strappers from five stables participated in the study, which was conducted on 91 horses. RESULTS: Resting girth tensions varied considerably. The mean tension on inhalation was 13 +/- 0.4 kg. Male strappers recorded higher tensions than females for all indices measured. Age and girth size of the horse did not significantly influence results. CONCLUSION: This study confirms that there is no standard for application of a girth and saddle in the Thoroughbred racing industry and the range of tensions applied was large. Strappers were unable to reliably apply the same tensions between horses. Values recorded at the extremes of the range seem inappropriate for racing conditions as low values would result in slippage of the saddle and higher values may result in girth galls and possible reduction in athletic performance. Further work is necessary to determine the point at which girth tension affects performance.

Abdomen↗
PubMed2000

Environmental investigations of Vibrio parahaemolyticus in oysters after outbreaks in Washington, Texas, and New York (1997 and 1998).

Total Vibrio parahaemolyticus densities and the occurrence of pathogenic strains in shellfish were determined following outbreaks in Washington, Texas, and New York. Recently developed nonradioactive DNA probes were utilized for the first time for direct enumeration of V. parahaemolyticus in environmental shellfish samples. V. parahaemolyticus was prevalent in oysters from Puget Sound, Wash.; Galveston Bay, Tex.; and Long Island Sound, N.Y., in the weeks following shellfish-associated outbreaks linked to these areas. However, only two samples (one each from Washington and Texas) were found to harbor total V. parahaemolyticus densities exceeding the level of concern of 10,000 g(-1). Pathogenic strains, defined as those hybridizing with tdh and/or trh probes, were detected in a few samples, mostly Puget Sound oysters, and at low densities (usually <10 g(-1)). Intensive sampling in Galveston Bay demonstrated relatively constant water temperature (27.8 to 31.7 degrees C) and V. parahaemolyticus levels (100 to 1,000 g(-1)) during the summer. Salinity varied from 14.9 to 29.3 ppt. A slight but significant (P < 0.05) negative correlation (-0.25) was observed between V. parahaemolyticus density and salinity. Based on our data, findings of more than 10,000 g(-1) total V. parahaemolyticus or >10 g(-1) tdh- and/or trh-positive V. parahaemolyticus in environmental oysters should be considered extraordinary.

Animals↗
PubMed2000

Gut focused behavioural treatment (biofeedback) for constipation and faecal incontinence in multiple sclerosis.

OBJECTIVES: To determine whether gut focused behavioural treatment (biofeedback) is a useful therapy in multiple sclerosis patients referred for constipation, incontinence, or a combination of these symptoms. Most patients with multiple sclerosis complain of constipation, faecal incontinence, or a combination of the two. Patients rate these bowel symptoms as having a major impact on their life. Until now the management of these problems has been empirical, with a lack of evaluated therapeutic regimes. METHODS: Thirteen patients (eight women, median age 38 years, median duration of multiple sclerosis 10 years) complaining of constipation, with or without faecal incontinence underwent a median of four sessions of behavioural treatment. Anorectal physiological tests were performed before therapy. Impairment and disability were rated with the Kurtzke score and the Cambridge multiple sclerosis basic score (CAMBS). Patients were contacted a median of 14 months after completion of treatment. RESULTS: A beneficial effect was attributed to biofeedback in five patients. Mild to moderate disability, quiescent and non-relapsing disease, and absence of progression of multiple sclerosis over the year before biofeedback were predictive of symptom improvement. No physiological test predicted the response to therapy. CONCLUSION: Biofeedback retraining is an effective treatment in some patients with multiple sclerosis complaining of constipation or faecal incontinence. A response is more likely in patients with limited disability and a non-progressive disease course.

Adult↗
PubMed1999

Historical Genetics: The Parentage of Chardonnay, Gamay, and Other Wine Grapes of Northeastern France.

The origins of the classic European wine grapes (Vitis vinifera) have been the subject of much speculation. In a search for parental relationships, microsatellite loci were analyzed in more than 300 grape cultivars. Sixteen wine grapes that have long been grown in northeastern France, including 'Chardonnay', 'Gamay noir', 'Aligoté', and 'Melon', have microsatellite genotypes consistent with their being the progeny of a single pair of parents, 'Pinot' and 'Gouais blanc', both of which were widespread in this region in the Middle Ages. Parentage analysis at 32 microsatellite loci provides statistical support for these relationships.

Journal Article↗
PubMed1999

A mutation in the MSH6 subunit of the Saccharomyces cerevisiae MSH2-MSH6 complex disrupts mismatch recognition.

In yeast, MSH2 interacts with MSH6 to repair base pair mismatches and single nucleotide insertion/deletion mismatches and with MSH3 to recognize small loop insertion/deletion mismatches. We identified a msh6 mutation (msh6-F337A) that when overexpressed in wild type strains conferred a defect in both MSH2-MSH6- and MSH2-MSH3-dependent mismatch repair pathways. Genetic analysis suggested that this phenotype was due to msh6-F337A sequestering MSH2 and preventing it from interacting with MSH3 and MSH6. In UV cross-linking, filter binding, and gel retardation assays, the MSH2-msh6-F337A complex displayed a mismatch recognition defect. These observations, in conjunction with ATPase and dissociation rate analysis, suggested that MSH2-msh6-F337A formed an unproductive complex that was unable to stably bind to mismatch DNA.

Adenosine Triphosphatases↗
PubMed1999

Effects of an Intergenerational Choir for Community-Based Seniors and College Students on Age-Related Attitudes.

The purpose of this study was to examine attitudes of college students and senior citizens towards each other by incorporating successful components of a senior citizens' music program into the "Adopt-A-Choir" program established in a university music education/therapy program. Data collection was accomplished using the Age Group Evaluation and Description Inventory (AGED), providing insight into attitudes classified in 4 domains/evaluative scales: Goodness, Positiveness, Vitality, and Maturity. Subjects ware members of the Senior Singers (n = 15, 15) and music education/therapy students enrolled in the Woman's Glee Club at a local university (n = 15, 12). Results of the pre/post AGED survey warn compared using the Wilcoxon Matched Pairs test, with means increasing significantly for the four domains (p <.02). Gains were greatest for the seniors, suggesting a stronger move from negative to positive attitudes. Though the gains were smaller with the university students, all changes were positive, with one exception: in the "vitality" domain, university student attitude ratings decreased on the continuum for "timid-assertive." Informal predictors further suggested the partnership between seniors and university students was enjoyed by both sets of participants.

Journal Article↗