Search PubMed⌕ Search

Biomedical subjects

W Webb

Publications and source records attributed to W Webb.

At least 19 recordsLinked to original sources
PubMed2001

Nitric oxide synthase isoform expression in a porcine model of granulation tissue formation.

BACKGROUND: This study was designed to determine whether the nitric oxide (NO) pathway is involved in wound granulation tissue formation. METHODS: A section of the pig abdominal wall (excluding the skin) was excised, creating an incisional hernia. The resulting defect was repaired with silicone sheeting in a manner that mimics a temporary abdominal wall closure. During the 14-day experimental period, porcine omentum adhered to the peritoneal edges of the defect and a highly vascularized granulation tissue formed on both sides of the sheeting. Granulation tissue thickness and wound fluid volume were monitored by ultrasonography and epigastric artery flow velocity was monitored by color Doppler flow analysis at days 2, 4, 7, 9, 11, and 14. Fluid was serially harvested from the wound compartment at days 2, 4, 7, 9, 11, and 14 for nitrite/ nitrate (NOx) analysis. Finally, granulation tissue was harvested at day 14 for immunohistochemical and molecular analyses. RESULTS: There was a significant increase in granulation tissue thickness and wound fluid volume during the 14-day study period. Blood flow to the wound increased significantly by day 4 and returned toward baseline by day 14. Wound fluid NOx levels significantly increased from days 7 to 11 and then decreased to near baseline values by day 14. Wound fluid arginine levels significantly decreased when compared with peritoneal fluid and plasma levels at day 14, while wound fluid ornithine levels significantly increased. Immunohistochemical analysis of granulation tissue at day 14 revealed nitric oxide synthase (NOS) 2 was present in the majority of the cells in the granulation tissue. NOS 3 was expressed in endothelial cells only, and NOS 1 expression was not observed in the granulation tissue. CONCLUSIONS: This study suggests that NO, NOS 2, and arginine may play critical roles in granulation tissue formation and wound healing. Arginase and NOS 2 may compete for available arginine as a substrate, thereby limiting later NO production in favor of sustained ornithine synthesis.

Abdominal Injuries↗
PubMed2001

Using telemedicine to avoid transfer of rural emergency department patients.

Access to emergency treatment in rural areas can often mean the difference between life and death. Telemedicine technologies have the potential of providing earlier diagnosis and intervention, of saving lives and of avoiding unnecessary transfers from rural hospital emergency departments to urban hospitals. This study examined the hypothetical impact of telemedicine services on patients served by the emergency departments of two rural Missouri hospitals and the potential financial impact on the affected hospitals. Of the 246 patients transferred to the hub hospital from the two facilities during 1996, 161 medical records (65.4 percent) were analyzed. Using a conservative approach, only 12 of these cases were identified as potentially avoidable transfers with the use of telemedicine. Of these 12, 5 were admitted to the hub hospital after transfer. In addition to this conservative estimate of avoidable transfers based on current availability of resources in the rural hospitals, two more aggressive scenarios were developed, based on an assumption of increased service availability in the rural hospitals. Economic multipliers were used to estimate the financial impacts on communities in each scenario. This evaluation study demonstrates the potential value of telemedicine use in rural emergency departments to patients, rural hospitals and rural communities.

Diagnosis-Related Groups↗
PubMed2000

Peer teaching and computer-assisted learning: An effective combination for surgical skill training?

BACKGROUND: The surgical literature suggests that collaborative learning using peers may be a valid way to teach surgical skills and there is a growing interest in the use of computer-assisted learning for this purpose. Combining this evolving technology with this type of teaching would theoretically offer a number of advantages including a reduction in the amount of faculty time devoted to this task. In this study, we evaluate the efficacy of a type of collaborative learning in a computer-assisted learning environment. MATERIALS AND METHODS: We designed a prospective, randomized study comparing novice learners who were allowed to work in pairs with those who worked independently in a specially equipped computer-assisted learning classroom. Both pretest and posttest assessments were performed by videotaping this skill. Three experts then evaluated the videotapes, in a blinded fashion. Three different outcomes were assessed. RESULTS: Seventy-seven subjects were enrolled in and completed the study. Comparison of the outcome measures demonstrated no between group difference in the average performance scores or posttest times. The proportion of subjects who correctly tied a square knot was significantly lower in the computer-assisted peer teaching group when compared with the computer-assisted learning alone group (P = 0.04). CONCLUSIONS: Collaborative learning in a computer-assisted learning environment is not an effective combination for teaching surgical skills to novices.

Computer-Assisted Instruction↗
PubMed2000

An evaluation of satisfaction with telemedicine among health-care professionals.

A survey was conducted among non-doctor health-care professionals in six rural counties in Missouri. The purpose of the survey was to establish baseline data to evaluate the effect of changes in the health-care sector, especially technology changes, on the job satisfaction, career satisfaction, relationships and communication activities of health professionals. The survey included three rural counties in which integrated telecommunication and interactive video telemedicine services were being installed, but before significant activities had begun, and three comparator counties without substantial integrated telecommunications infrastructure and telemedicine services. During a one-month study period, 1108 questionnaires were distributed. The total response rate was 50.1% (n = 555). Of the respondents, 30.3% indicated that technology in health-care was having a large effect on their work, although only 18.2% indicated that telemedicine and telecommunications were having a large effect. No systematic differences were found among the health professionals in the two communities at the time telemedicine equipment was being installed.

Health Knowledge, Attitudes, Practice↗
PubMed1987

Accuracy of person perception: do people know what kinds of impressions they convey?

Do people know what kinds of impressions they convey to other people during particular social interactions? In a study designed to answer this question, subjects interacted individually with three partners on each of four different tasks. After each interaction, participants reported their impressions of the other person's likability and competence. They also postdicted the impressions they believed they conveyed to the other person along the same dimensions. Accuracy was computed as recommended by Cronbach (1955) and by Kenny's (1981) Social Relations Model. Subjects could tell to a significant degree how the impressions they conveyed to their partners changed over time (time accuracy) and how they changed over time in different ways with different partners (differential accuracy). They could also tell how their competence was differentially perceived by different partners (dyadic accuracy). However, they were not very accurate at discerning which partners perceived them as most competent or most likable across all interactions (person accuracy). Subjects believed that they conveyed similar impressions of themselves to all of their partners, although actually partners evidenced little agreement with each other in their impressions of a given subject. The implications of these findings for symbolic-interactionist theories of the development of the self and impression-management perspectives on social behavior are described.

Humans↗
PubMed1985

Emergency management of tracheal rupture.

We have described a patient in whom tracheal rupture occurred during prolonged mechanical ventilation. Appropriate intensive respiratory care management, including the use of the minimal leak technique, was used. Our patient unfortunately had nearly every known predisposing factor for tracheal damage.

Adult↗
PubMed1981

The effects of leucocyte elastase on the mechanical properties of adult human articular cartilage in tension.

The effects of leucocyte elastase on the tensile properties of adult human articular cartilage were examined in detail in 99 specimens from hip, knee and ankle joints in the age range 16-83 years. The results showed that elastase reduced the tensile stiffness of cartilage, both at low stress and at fracture. The tensile strength of cartilage was also considerably reduced by the action of elastase. Biochemical analysis of the incubation media, and the specimens, revealed that 90%, or more, of the proteoglycan was released from the cartilage, whilst the release of collagen was negligible. Leucocyte elastase is known to degrade the non-helical terminal peptides of cartilage collagen molecules and thereby disrupt the main intermolecular cross-links in collagen fibrils. A previous study (Kempson, G.E., Tuke, M.A., Dingle, J.T., Barrett, A.J. and Horsfield, P.H. (1976) Biochim. Biophys. Acta 428, 741-760) showed the lack of effect of proteoglycan degradation alone on the tensile strength and stiffness of cartilage. The reduction in strength and stiffness recorded in the present study can, therefore, be attributed to the action of elastase on the collagen in cartilage and it emphasises the important of covalent intermolecular cross-links to the mechanical properties of collagen fibrils.

Adolescent↗