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Biomedical subjects

B H Jones

Publications and source records attributed to B H Jones.

At least 19 recordsLinked to original sources
PubMed2006

Ambulatory physical activity during United States Army basic combat training.

Electronic pedometers were used to quantify locomotor physical activity during an entire 9-week United States Army Basic Combat Training (BCT) cycle. Pedometers were worn on the hips of 4 trainees in each of 10 BCT companies during all BCT activities. Investigators obtained pedometer readings (steps) on a daily basis, and estimated travel distances were obtained by multiplying steps by the average individual step length. A short questionnaire was administered daily to assure trainees wore the pedometers and trained with their companies all day. Trainees performed an average +/- SD of 16 311 +/- 5826 steps/day and traveled an estimated 11.7 +/- 4.4 kilometers/day. The highest daily locomotor activity was during the field training exercise in which trainees took an average +/- SD of 22 372 +/- 12 517 steps/day traveling an estimated 16.2 +/- 9.7 kilometers/day. Differences among the 10 companies ranged from 14 720 +/- 6649 steps/day to 18 729 +/- 6328 steps/day. This survey provided the first examination of locomotor physical activity during an entire BCT cycle.

Adult↗
PubMed2006

Temporal and spatial variability of fecal indicator bacteria in the surf zone off Huntington Beach, CA.

Fecal indicator bacteria concentrations measured in the surf zone off Huntington Beach, CA from July 1998-December 2001 were analyzed with respect to their spatial patterns along 23 km of beach, and temporal variability on time scales from hourly to fortnightly. The majority of samples had bacterial concentrations less than, or equal to, the minimum detection limit, but a small percentage exceeded the California recreational water standards. Areas where coliform bacteria exceeded standards were more prevalent north of the Santa Ana River, whereas enterococci exceedances covered a broad area both north and south of the river. Higher concentrations of bacteria were associated with spring tides. No temporal correspondence was found between these bacterial events and either the timing of cold water pulses near shore due to internal tides, or the presence of southerly swell in the surface wave field. All three fecal indicator bacteria exhibited a diel cycle, but enterococci rebounded to high nighttime values almost as soon as the sun went down, whereas coliform levels were highest near the nighttime low tide, which was also the lower low tide.

Bacterial Physiological Phenomena↗
PubMed2005

Interventions to prevent softball related injuries: a review of the literature.

OBJECTIVES: To examine the published evidence on interventions to prevent softball related injuries among adults, and to encourage more epidemiologic research as a foundation for future softball injury prevention efforts. METHODS: The authors reviewed literature identified from six electronic databases for studies on softball related injuries. The search was limited to studies written in the English language, published between 1970 and 2002, and involving adult populations. Research was excluded that evaluated baseball ("hard ball") related injuries or was aimed at injury treatment. Identified studies were categorized by study design. Intervention/prevention papers were evaluated further and described in detail. RESULTS: The search strategy identified 39 studies specifically related to softball. Most studies were case reports/case series (n=13) or descriptive studies (n=11); only four were analytic or intervention/prevention studies. Studies collected data in a variety of ways, often without denominator data to permit calculation of injury rates. Studies also did not differentiate between slow or fast pitch softball activities and most did not mention the type of softball that was used. CONCLUSIONS: Surprisingly few studies exist on interventions to reduce injuries during softball, one of the most popular recreational sports in the US. Of the existing literature, much attention has been on sliding related injuries, which comprise only a segment of softball injuries. Basic epidemiologic studies describing the nature, severity, and risk factors for softball injuries in a variety of populations are needed, followed by additional intervention evaluation studies aimed at modifiable risk factors.

Adult↗
PubMed2004

Histological quality of polyps resected using the cold versus hot biopsy technique.

BACKGROUND AND STUDY AIMS: The monopolar hot biopsy technique is a widespread method of removing and cauterizing small colonic polyps. Due to the insulated cups of the biopsy forceps, it also allows adequate histological interpretation of the resected specimen. In our experience, polyps removed using the monopolar hot biopsy technique have been less histologically interpretable in comparison with polyps removed using cold biopsy forceps. The aim of this study was to assess and compare the diagnostic quality of polyps obtained using the hot biopsy and cold biopsy techniques. PATIENTS AND METHODS: This was a prospective study of consecutive patients undergoing colonoscopy with removal of polyps using either hot biopsy or cold biopsy techniques. One experienced endoscopist using the same techniques carried out the biopsies. An experienced gastrointestinal pathologist, blinded to the technique used, evaluated the specimens for diameter, artifacts, cautery damage, tissue fragmentation, and general histological and diagnostic quality. Statistical analysis was carried out using the chi-squared test, Fisher's exact test, and Student's t-test. RESULTS: Forty-three consecutive patients (84 % men; mean age 63.8 +/- 15 years) underwent 88 biopsies (45 hot biopsies and 43 cold biopsies). There were no statistically significant differences between the two study groups with regard to demographic data, indications for colonoscopy, endoscopic findings, or polyp size. Cautery damage, architectural distortion, and tissue fragmentation occurred more frequently in polyps resected using the hot biopsy technique ( P < 0.001). CONCLUSIONS: The quality of the specimens removed by cold biopsy was generally better than when using hot biopsy technique. Histological evaluation is more difficult in polyps resected with the hot biopsy technique in comparison with the cold biopsy technique. When the nature of polyps affects the patient's management, a biopsy may be obtained before polyp coagulation.

Aged↗
PubMed2004

Influence of an injury reduction program on injury and fitness outcomes among soldiers.

OBJECTIVE: This study evaluated the influence of a multiple injury control intervention on injury and physical fitness outcomes among soldiers attending United States Army Ordnance School Advanced Individual Training. METHODS: The study design was quasiexperimental involving a historical control group (n = 2559) that was compared to a multiple intervention group (n = 1283). Interventions in the multiple intervention group included modified physical training, injury education, and a unit based injury surveillance system (UBISS). The management responsible for training independently formed an Injury Control Advisory Committee that examined surveillance reports from the UBISS and recommended changes to training. On arrival at school, individual soldiers completed a demographics and lifestyle questionnaire and took an army physical fitness test (APFT: push-ups, sit-ups, and two mile run). Injuries among soldiers were tracked by a clinic based injury surveillance system that was separate from the UBISS. Soldiers completed a final APFT eight weeks after arrival at school. RESULTS: Cox regression (survival analysis) was used to examine differences in time to the first injury while controlling for group differences in demographics, lifestyle characteristics, and physical fitness. The adjusted relative risk of a time loss injury was 1.5 (95% confidence interval 1.2 to 1.8) times higher in the historical control men and 1.8 (95% confidence interval 1.1 to 2.8) times higher in the historical control women compared with the multiple intervention men and women, respectively. After correcting for the lower initial fitness of the multiple intervention group, there were no significant differences between the multiple intervention and historical control groups in terms of improvements in push-ups, sit-ups, or two mile run performance. CONCLUSIONS: This multiple intervention program contributed to a reduction in injuries while improvements in physical fitness were similar to a traditional physical training program previously used at the school.

Adolescent↗
PubMed2003

Automated high-throughput probe production for DNA microarray analysis.

DNA microarrays have become an established tool for gene expression profiling. Construction of these microarrays using immobilized cDNAs is a common experimental strategy. However, this is extremely laborious, requiring the preparation of hundreds or thousands of cDNA probes. To minimize this initial bottleneck, we developed a comprehensive high-throughput robotic system to prepare DNA probes suitable for microarray analysis with minimal user intervention. We describe an automated system using the MultiPROBE Nucleic Acid Purification Workstation to provide the liquid handling and other functions needed to optimize this process. We were able to carry out fully automated plasmid cDNA isolation, PCR assay setup, and PCR purification and also to direct the characterization and tracking of DNA probes during processing. Protocols began with the initial preparation of a plasmid DNA archive of bacterial stocks in parallel 96-well plates (192 samples/run) and continued through to the dilution and reformatting of chip-ready DNA probes in 384-well format. These and other probe production procedures and additional instrument systems were used to process fully a set of mouse cDNA clones that were then validated by differential gene expression analysis.

Animals↗
PubMed2001

Expression and localization of caveolin-1, and the presence of membrane rafts, in mouse and Guinea pig spermatozoa.

In somatic cells, caveolin-1 plays several roles in membrane dynamics, including organization of detergent-insoluble lipid rafts, trafficking of cholesterol, and anchoring of signaling molecules. Events in sperm capacitation and fertilization require similar cellular functions, suggesting a possible role for caveolin-1 in spermatozoa. Immunoblot analysis demonstrated that caveolin-1 was indeed present in developing mouse male germ cells and both mouse and guinea pig spermatozoa. In mature spermatozoa, caveolin-1 was enriched in a Triton X-100-insoluble membrane fraction, as well as in membrane subdomains separable by means of their light buoyant densities through sucrose density gradient centrifugation. These data indicated the presence of membrane rafts enriched in caveolin-1 in spermatozoa. Indirect immunofluorescence analysis revealed caveolin-1 in the regions of the acrosome and flagellum in sperm of both species. Confocal immunofluorescence analysis of developing mouse male germ cells demonstrated partial co-localization with a marker for the acrosome. Furthermore, syntaxin-2, a protein involved in acrosomal exocytosis, was present in both raft and nonraft fractions in mature sperm. Together, these data indicated that sperm membranes possess distinct raft subdomains, and that caveolin-1 localized to regions appropriate for involvement with acrosomal biogenesis and exocytosis, as well as signaling pathways regulating such processes as capacitation and flagellar motility.

Acrosome↗
PubMed2001

Generation of enterococci bacteria in a coastal saltwater marsh and its impact on surf zone water quality.

Elevated levels of enterococci bacteria, an indicator of fecal pollution, are routinely detected in the surf zone at Huntington State and City Beaches in southern California. A multidisciplinary study was carried out to identify sources of enterococci bacteria landward of the coastline. We find that enterococci bacteria are present at high concentrations in urban runoff, bird feces, marsh sediments, and on marine vegetation. Surprisingly, urban runoff appears to have relatively little impact on surf zone water quality because of the long time required for this water to travel from its source to the ocean. On the other hand, enterococci bacteria generated in a tidal saltwater marsh located near the beach significantly impact surf zone water quality. This study identifies a potential tradeoff between restoring coastal wetlands and protecting beach water quality and calls into question the use of ocean bathing water standards based on enterococci at locations near coastal wetlands.

Conservation of Natural Resources↗
PubMed2001

Risk factors for training-related injuries among men and women in basic combat training.

PURPOSE: Past investigations indicate that training-related injuries are associated with certain performance-oriented measures of physical fitness and certain lifestyle characteristics. This study examined associations between injuries, direct (physiological) measures of physical fitness, and lifestyle characteristics. METHODS: Subjects were 756 men and 474 women performing the standardized activities involved in U.S. Army Basic Combat Training (BCT). Before BCT, a subsample of subjects (182 men and 168 women) were administered a series of tests that included a treadmill running test (peak VO2), dual-energy x-ray absorptiometry (for body composition), several measures of muscle strength, a hamstring flexibility test, and a vertical jump. A questionnaire addressed smoking habits and prior physical activity. All subjects were administered the Army Physical Fitness test consisting of push-ups, sit-ups, and a 3.2-km run. Gender, age, stature, and body mass were obtained from physical examination records. Injuries incurred during BCT were transcribed from medical records; for each medical visit, the diagnosis, anatomical location, disposition (final outcome of visit), and days of limited duty were recorded. RESULTS: Women had over twice the injury rate of men. For men and women, fewer push-ups, slower 3.2-km run times, lower peak VO2, and cigarette smoking were risk factors for time-loss injury. Among the men only, lower levels of physical activity before BCT and both high and low levels of flexibility were also time-loss injury risk factors. Multivariate analysis revealed that lower peak VO2 and cigarette smoking were independent risk factors for time-loss injury. CONCLUSIONS: Lower aerobic capacity and cigarette smoking were independently associated with a higher likelihood of injury in both men and women during a standardized program of physical training. Further studies are needed to assess associations between injury and body composition and muscular strength.

Adolescent↗
PubMed2000

Functional relationships between capacitation-dependent cell signaling and compartmentalized metabolic pathways in murine spermatozoa.

Spermatozoa are highly polarized cells with specific metabolic pathways compartmentalized in different regions. Previously, we hypothesized that glycolysis is organized in the fibrous sheath of the flagellum to provide ATP to dynein ATPases that generate motility and to protein kinases that regulate motility. Although a recent report suggested that glucose is not essential for murine sperm capacitation, we demonstrated that glucose (but not lactate or pyruvate) was necessary and sufficient to support the protein tyrosine phosphorylation events associated with capacitation. The effect of glucose on this signaling pathway was downstream of cAMP, and appeared to arise indirectly as a consequence of metabolism as opposed to a direct signaling effect. Moreover, the phosphorylation events were not affected by uncouplers of oxidative respiration, inhibitors of electron transfer, or by a lack of substrates for oxidative respiration in the medium. Further experiments aimed at identifying potential regulators of sperm glycolysis focused on a germ cell-specific isoform of hexokinase, HK1-SC, which localizes to the fibrous sheath. HK1-SC activity and biochemical localization did not change during sperm capacitation, suggesting that glycolysis in sperm is regulated either at the level of substrate availability or by downstream enzymes. These data support the hypothesis that ATP specifically produced by a compartmentalized glycolytic pathway in the principal piece of the flagellum, as opposed to ATP generated by mitochondria in the mid-piece, is strictly required for protein tyrosine phosphorylation events that take place during sperm capacitation. The relationship between these pathways suggests that spermatozoa offer a model system for the study of integration of compartmentalized metabolic and signaling pathways.

Adenosine Triphosphate↗
PubMed2000

Transcriptional regulation of the adipocyte fatty acid synthase gene by agouti: interaction with insulin.

Mice carrying dominant mutations at the agouti locus exhibit ectopic expression of agouti gene transcripts, obesity, and type II diabetes through unknown mechanisms. To gain insight into the role of agouti protein in modulating adiposity, we investigated regulation of a key lipogenic gene, fatty acid synthase (FAS) by agouti alone and in combination with insulin. Both agouti and insulin increase FAS activity in 3T3-L1 and in human adipocytes. Agouti and insulin independently and additively increase FAS activity in 3T3-L1 adipocytes. We further investigated the mechanism responsible for the agouti-induced FAS expression in these cells and demonstrated that both insulin (3-fold increase) and agouti (2-fold) increased FAS gene expression at the transcriptional level. Furthermore, insulin and agouti together exerted additive effects (5-fold increase) on FAS gene transcription. Transfection assays of FAS promoter-luciferase fusion gene constructs into 3T3-L1 adipocytes indicated that the agouti response element(s) is (are) located in the -435 to -415 region (-435/-415) of the FAS promoter. Nuclear proteins binding to this novel sequence are adipocyte specific. Thus the agouti response sequences mapped to a region upstream of the insulin-responsive element (which we previously reported to be located at -67/-52), consistent with additive effects of these two factors on FAS gene transcription.

3T3 Cells↗
PubMed2000

Exercise-related injuries among women: strategies for prevention from civilian and military studies.

SCOPE OF THE PROBLEM: The numerous health benefits of physical activity have been well documented, resulting in public health support of regular physical activity and exercise. Although beneficial, exercise also has corresponding risks, including musculoskeletal injuries. The incidence and risk factors for exercise-related injury have been poorly assessed in women. Many civilian exercise activities (e.g., jogging, walking, and erobics) have corollaries in military physical training; injury incidence and risk factors associated with military physical training have been more thoroughly studied. ETIOLOGIC FACTORS: Injury risks increase as the amount of training increases (increased xposure). The same exercise parameters that can be modified to enhance physical fitness (i.e., frequency, duration, and intensity) also influence the risk for injury in a dose-response manner. Higher levels of current physical fitness (aerobic fitness) protect the participant against future injury. A history of previous injury is a risk factor for future injury. Smoking cigarettes has been associated with increased risk for exercise-related injury. Studies conducted in military populations suggest that the most important risk factor for injuries among persons engaged in vigorous weight-bearing aerobic physical activity might be low aerobic fitness rather than female sex. RECOMMENDATIONS FOR PREVENTION: Because of the limited scientific research regarding women engaging in exercise, general recommendations are provided. Women starting exercise programs should be realistic about their goals and start slowly at frequency, duration, and intensity levels commensurate with their current physical fitness condition. Women should be informed about the early indicators of potential injury. Women who have sustained an injury should take precautions to prevent reinjury (e.g., ensuring appropriate recovery and rehabilitation). RESEARCH AGENDA: In general, a combination of factors affects the risk for exercise-related injury in women. How these factors act singly and in combination to influence injury risk is not well understood. Additional research regarding exercise-related injury in women is needed to answer many of the remaining epidemiologic questions and to help develop exercise programs that improve health while reducing the risk for injury. CONCLUSION: Exercise is an important component in improving and maintaining health; however, injury is also an accompanying risk. A review of key military and civilian research studies regarding exercise-related injuries provides some clues to reducing these injuries in women. Greater adherence to exercise guidelines can help decrease these risks.

Athletic Injuries↗
PubMed2000

Validation of a peptide mapping method for a therapeutic monoclonal antibody: what could we possibly learn about a method we have run 100 times?

Peptide mapping is a key analytical method for studying the primary structure of proteins. The sensitivity of the peptide map to even the smallest change in the covalent structure of the protein makes it a valuable 'finger-print' for identity testing and process monitoring. We recently conducted a full method validation study of an optimised reverse-phase high-performance liquid chromatography (RP-HPLC) tryptic map of a therapeutic anti-CD4 IgG1 monoclonal antibody. We have used this method routinely for over 1 year to support bioprocess development and test production lots for clinical trials. Herein we summarize the precision and ruggedness of the testing procedure and the main findings with respect to 'coverage of amino acid sequence' and limits-of-detection for various hypothetical structural variants. We also describe, in more detail, two unanticipated insights into the method gained from the validation study. The first of these is a potentially troublesome side-product arising during the reduction/alkylation step. Once the cause of this side-product was identified, it was easily prevented. We also report on subtle changes to the peptide map upon extended storage of the digest in the autosampler. These findings helped us to develop a 'robust' method for implementation in a quality control laboratory.

Amino Acid Sequence↗
PubMed2000

Cigarette smoking and exercise-related injuries among young men and women.

BACKGROUND: We evaluate whether a recent history of cigarette smoking is a risk factor for exercise-related injuries sustained during Army basic training, controlling for factors such as demographic, physical fitness, and health variables. METHODS: We conducted an observational cohort study in 1087 male and 915 female Army recruits undergoing 8-week basic military training. Data were collected from questionnaires, anthropometric measurements, physical fitness tests, company training logs, and medical records of all clinic visits. RESULTS: During the 8-week training period, 33% of men and 50% of women had at least one clinic visit for injury, including 14% of men and 25% of women who lost more than 5 days of training due to injury. Recruits who reported smoking at least one cigarette in the month prior to beginning basic training (which was conducted in a smoke-free environment) had significantly higher injury rates during training than those who did not report smoking (40% versus 29% for men, and 56% versus 46% for women). The relationship with smoking history was present most strongly for overuse injuries (32% versus 24% in men and 51% versus 40% in women). Multiple logistic regression analyses controlling for all other factors consistently showed adjusted odds ratios of about 1.5 for injury rate in those with a history of smoking compared to those without. CONCLUSIONS: The association of history of cigarette smoking with injury occurrence was consistent throughout the analyses, with very little confounding by other factors. The detrimental effects of smoking on injuries appears to persist at least several weeks after cessation of smoking.

Adolescent↗
PubMed2000

Effect of rest from running on overuse injuries in army basic training.

BACKGROUND: It has been hypothesized that a period of rest from running in the early weeks of basic military training will prevent stress fractures among recruits. DESIGN: Modification of running schedules in companies of Army recruits undergoing basic military training was assigned. SETTING/PARTICIPANTS: Six male training companies were enrolled and followed during their 8 weeks of basic military training at Fort Bliss, Texas, in summer/fall 1989. INTERVENTION: Intervention companies were asked to rest from running during the second, third, or fourth week of basic military training. MAIN OUTCOME MEASURES: Data were collected from questionnaires, anthropometric measurements, Army physical fitness tests, company training logs, and medical record abstraction of all clinic visits. RESULTS: Among the 1357 enrolled male recruits, there were 236 (17%) with overuse injury and 144 (11%) with traumatic injury, resulting in 535 clinic visits and 1927 training days lost. Stress fracture/reaction rates varied from 3 to 8 per 100 recruits among the intervention companies and 2 to 7 per 100 recruits among the non-intervention companies. Total injury rates were 18 to 35 per 100 recruits in the intervention companies and 18 to 29 per 100 recruits in the non-intervention companies. CONCLUSIONS: The study provided no evidence for a protective effect on overuse injuries of resting from running for 1 week early in basic military training. There was varied physical training among the companies, however, with variation of injury rates that likely related to factors other than the intervention.

Adolescent↗
PubMed2000

Self-reported risk-taking behaviors and hospitalization for motor vehicle injury among active duty army personnel.

BACKGROUND: Motor vehicle crashes are a leading cause of injury in the Army. Behaviors increasing risk for motor vehicle crashes are also prevalent, but research has not linked these behaviors directly to injury outcomes (e.g., hospitalizations). METHODS: To evaluate the relationship between behavior and motor vehicle crash injuries, 99, 981 Army personnel who completed Health Risk Appraisal surveys in 1992 were followed for up to 6 years. Cox proportional hazards modeling was used to evaluate speeding, seat belt use, drinking patterns, and demographics. RESULTS: A total of 429 soldiers were hospitalized for motor vehicle injury. Unadjusted analyses revealed that heavy drinking, drinking and driving, speeding, low seat belt use, younger age, minority race/ethnicity, and enlisted rank were significantly associated with motor vehicle injury, but neither smoking nor gender was. Multivariate models showed a significant trend of increasing injury risk with younger ages. Soldiers under age 21 were injured almost five times more often than those over age 40 (HR 4.89, 2.56-9.33). Also associated with risk for hospitalizations were minority race (HR 1.78, 1.46-2.18), heaviest drinkers versus abstainers (HR 1.81, 1.11-2.94), and seat belt use of 50% or less versus 100% (HR 1.40, 1.07-1.85). Although nonsignificant, there was evidence of an age-drinking interaction where the difference in injury risk between those older and those younger than 21 was greatest at low alcohol consumption levels. CONCLUSIONS: Modifiable risk factors associated with motor vehicle injuries include heavy drinking and low seat belt use. Programs targeting these behaviors that meet the needs of young and minority soldiers are needed. The high density of young, at-risk soldiers residing in base housing may provide a unique opportunity for a residential intervention program.

Accidents, Traffic↗