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Biomedical subjects

J M Webb

Publications and source records attributed to J M Webb.

At least 19 recordsLinked to original sources
PubMed2005

Revision of Heterocloeon McDunnough (Ephemeroptera: Baetidae).

The North American genus Heterocloeon McDunnough is redefined and shown to be distinct from other two-tailed Baetis complex genera, including Acentrella Bengtsson and Plauditus Lugo-Ortiz and McCafferty, which are also represented in North America. Heterocloeon is divided into three distinct subgenera, including Heterocloeon s.s., Iswaeon McCafferty and Webb, new subgenus, and Jubilatum McCafferty and Jacobus, new subgenus. Cladistic analysis supports the recognition of these subgenera within a genus defined by the presence of an apomorphic secondary ridge or denticle row on the larval claw; Heterocloeon s.s. and Jubilatum being sister groups, with their stem and Iswaeon branching basally within the Heterocloeon clade. The subgenus Heterocloeon, which possesses larval prothoracic osmobranchiae, retains the traditional species makeup of the genus. Iswaeon, which possesses a basally narrowed labial palp segment 2 and tibiae, and primary claw denticles of subequal length, includes a revalidated H. anoka (Daggy); H. davidi Waltz and McCafferty, new species; and H. rubrolaterale (McDunnough), new combination. Jubilatum, which posssesses an adenticulate secondary ridge on the claws and specialized tibial setation, includes H. amplum (Traver), new combination, and H. grande (Wiersema and Long), new combination. Previous confusion of H. anoka and Plaudituspunctiventris (McDunnough) is also resolved, with adult color patterns in Iswaeon and Plauditus shown to be of diagnostic importance.

Animals↗
PubMed2001

Interface pressure produced by the traction post on a standard orthopaedic table.

Lower limb traction is applied with counter traction in the groin. The resultant tissue pressures can be high and may result in skin necrosis or nerve palsies. Volunteers were positioned on a fracture table and traction applied to the left leg. Perineal contact pressures were measured using pressure transducers connected to a laptop computer. Pressure readings and pain scores were recorded with different types of padding, whilst the leg was repositioned. Maximal pressures exceeded the 70 mmHg limit known to cause tissue damage. Larger (10 cm) padding devices significantly reduced the pressures. When employing the perineal traction post, care should be taken to pad this carefully to avoid the sequelae of high tissue pressure.

Humans↗
PubMed2001

Quantified kinematics of the injury to the posterior cruciate ligament: a computer-aided design simulation study.

OBJECTIVE: To quantify the kinematics of the injury to the posterior cruciate and the other major knee ligaments as a function of the knee flexion angle at the moment of impact. DESIGN: Computer-aided design modelling was used to investigate the strain response of all major knee ligaments during antero-posterior abnormal tibio-femoral translation at 0-90 degrees knee flexion. BACKGROUND: It is generally believed that the likelihood of injury to the posterior cruciate ligament following anterior impact is higher in the flexed knee. However, there are no kinematical studies to quantify this clinical observation or investigate the role of the other knee ligaments in the above situation. METHODS: Computer calculations of the individual ligament strain were plotted against the magnitude of posterior tibial translation. Additionally, the strain rate for each ligament (defined as the ligament strain produced per mm of posterior tibial linear translation) was calculated as the slope of the strain-displacement curve for all tested degrees of knee flexion. RESULTS: The posterior cruciate ligament has been shown to be the primary restraint to posterior tibial translation in all degrees of knee flexion. However, at 90 degrees of knee flexion the strain rate of the posterior cruciate ligament is approximately half that in the fully extended knee and the posterior cruciate ligament is the only ligament to resist posterior tibial translation. CONCLUSIONS: The strain behaviour of the posterior cruciate ligament during injury is highly dependent on the knee flexion during the moment of impact. Forced posterior tibial translation in the 90 degrees flexed knee may result in isolated posterior cruciate ligament deficit rather than a complex ligament disruption. The strain rate of a ligament as introduced in the present study is a quantified parameter related to the resistance that the ligament imposes to an abnormal joint movement. Relevance. This study provides insight into the differential strain of the knee ligaments during impacts that result in posterior cruciate ligament injury. Studies that quantify the strain behaviour of individual knee ligaments are important to the understanding, diagnosis and prevention of injuries sustained during contact sports and high-energy road traffic accidents.

Biomechanical Phenomena↗
PubMed2000

Delirium in the intensive care unit: are we helping the patient?

The intensive care unit (ICU) represents a dynamic interaction between patient factors and interventional factors. The complexity of this situation can generate an impaired consciousness in the patients. The critical care provider is faced with deducing the etiology and treatment of delirium in the ICU. Many of the therapeutic agents that are used in the ICU may precipitate delirium. Patients may also experience delirium as part of their underlying medical conditions. Withdrawal syndromes, delirium tremens in particular, are known to cause delirium. By a combination of appropriate selection of medications and an awareness of delirium as a side effect, the patient in the ICU may be treated in a manner to minimize the clouding of consciousness. An understanding of the proposed pathophysiology of various types of delirium will allow appropriate clinical measures to be taken.

Alcohol Withdrawal Delirium↗
PubMed1999

Percutaneous repair of the ruptured tendo Achillis.

Percutaneous repair of the ruptured tendo Achillis has a low rate of failure and negligible complications with the wound, but the sural nerve may be damaged. We describe a new technique which minimises the risk of injury to this nerve. The repair is carried out using three midline stab incisions over the posterior aspect of the tendon. A No. 1 nylon suture on a 90 mm cutting needle approximates the tendon with two box stitches. The procedure can be carried out under local anaesthesia. We reviewed 27 patients who had a percutaneous repair at a median interval of 35 months after the injury. They returned to work at four weeks and to sport at 16. One developed a minor wound infection and another complex regional pain syndrome type II. There were no injuries to the sural nerve or late reruptures. This technique is simple to undertake and has a low rate of complications.

Achilles Tendon↗
PubMed1998

Endoscopic reconstruction for isolated anterior cruciate ligament rupture.

We treated 90 patients with an isolated injury to the anterior cruciate ligament (ACL) by reconstruction using a patellar tendon autograft and interference screw fixation. Of these, 82 (91%) were available for review at 24 months. Two grafts and two contralateral ACLs had ruptured during sport and there was one case of atraumatic graft resorption. Using the assessment of the International Knee Documentation Committee (IKDC), 86% of the remaining patients were normal or nearly normal. The median Lysholm knee score was 95/100 and 84% of patients were participating in moderate to strenuous activity. All had grade-0 or grade-1 Lachman, pivot-shift and anterior-drawer tests. Measurement with the KT1000 arthrometer gave a side-to-side difference of <3 mm of anterior tibial displacement in 90%. Sixty-six radiographs were IKDC grade A and one was grade B. Pain on kneeling was present in 31% and graft site pain in 44%. At 24 months after operation all patients had excellent knee stability, a high rate of return to sport and minimal radiological evidence of degenerative change. Our series therefore represents a basis for comparison of results using other techniques and after more severe injuries.

Adolescent↗
PubMed1998

The use of cold compression dressings after total knee replacement: a randomized controlled trial.

This prospective, controlled study compared cold compressive dressings with wool and crepe in the postoperative management of patients undergoing total knee replacement (TKR). Forty TKR patients were assessed for blood loss, pain, swelling, and range of motion. Patients in the cold compression group had less blood loss through suction drainage (982 mL versus 768 mL). A higher proportion of patients in the treatment group did not require blood transfusion postoperatively. Mean opiate requirements were lower in the cold compression group (0.57 versus 0.71 mg/kg/48 hours). The cold compression device appeared to reduce blood loss and pain following TKR.

Aged↗
PubMed1997

Treatment of liver injuries at level I and level II centers in a multi-institutional metropolitan trauma system. The Midwest Trauma Society Liver Trauma Study Group.

OBJECTIVE: The development of trauma systems and trauma centers has had a major impact on the fate of the critically injured patient. However, some have suggested that care may be compromised if too many trauma centers are designated for a given area. As of 1987, the state of Missouri had designated six adult trauma centers, two Level I and four Level II, for the metropolitan Kansas City, Mo, area, serving a population of approximately 1 million people. To determine whether care was comparable between the Level I and II centers, we conducted a concurrent evaluation of the fate of patients with a sentinel injury, hepatic trauma, over a 6-year period (1987-1992) who were treated at these six trauma centers. METHODS: All patients during the 6-year study period who suffered liver trauma and who survived long enough to be evaluated by computerized tomography or celiotomy were entered into the study. Patients with central nervous system trauma were excluded from analysis. Information concerning mechanism of injury, RTS, Injury Severity Score (ISS), presence of shock, liver injury scoring, mode of treatment, mortality, and length of stay were recorded on abstract forms for analysis. Care was evaluated by mortality, time to the operating room (OR), and intensive care unit (ICU) and hospital length of stay. RESULTS: Over the 6-year period 300 patients with non-central nervous system liver trauma were seen. Level I centers cared for 195 patients and Level II centers cared for 105. There was no difference in mean ISS or ISS > 25 between Level I and II centers. Fifty-five (28%) patients arrived in shock at Level I centers and 24 (23%) at Level II centers. Forty-eight patients (16%) died. Thirty-two (16%) died at Level I centers, and 16 (15%) died at Level II centers. Twenty of 55 patients (36%) in shock died at Level I centers, and 11 of 24 (46%) died at Level II centers (p = 0.428). Forty-three patients (22%) had liver scaling scores of IV-VI at Level I centers, and 10 (10%) had similar scores at Level II centers (p < 0.01). With liver scores IV-VI, 22 of 43 (51%) died at Level I centers and 10 of 14 (71%) died at Level II centers (p = 0.184). There was no difference in mean time or in delays beyond 1 hour to the OR for those patients in shock between Level I and II centers. There was a longer ICU stay at Level II centers (5.0 +/- 8.3 vs. 2.8 +/- 8.4 days, p = 0.04). This difference was confined to penetrating injuries. There was no difference in hospital length of stay. CONCLUSIONS: In a metropolitan trauma system, when Level I and II centers were compared for their ability to care for victims of hepatic trauma, there was no discernible difference in care rendered with respect to severity of injury, mortality, delays to the OR, or hospital length of stay. It was observed that more severe liver injuries were seen at Level I centers, but this did not seem to significantly affect care at Level II centers. There was a longer ICU stay observed at Level II centers owing to penetrating injuries, possibly because there were fewer penetrating injuries treated at these facilities. Although the bulk of patients were seen at Level I centers, care throughout the system was equivalent.

Adult↗
PubMed1997

Changes in crime rates and family-related values in selected East European countries.

Observations and longitudinal comparisons of emerging trends within formerly socialist East European countries offer a unique opportunity to observe some of the social policies typical of the capitalist and socialist systems and their influence on society. Some of the emerging trends in the Czech Republic, former East Germany, and Russia pertaining to general areas of public health, family, and crime are described. Effects of these changes are discussed within the framework of a recently proposed multiple regression model of criminal behavior in which criminality is attributed to the confluence of gross inequalities in the distribution of wealth and to the disintegration of the traditional family. The changes should be considered in the conduct of research.

Adult↗
PubMed1997

Autoimmune bullous diseases.

Patients with autoimmune bullous diseases are occasionally encountered in primary care practice, usually in middle-aged and older patients. The differential diagnosis includes nonimmune causes, such as contact dermatitis, infections and bullous reactions to drugs or insect bites. An autoimmune blistering disease may be distinguished by the age of the patient when the disease first appears, the morphology and distribution of the lesions and the presence or absence of mucosal lesions and scarring. Because the clinical presentations of blistering disorders are often similar, special immunofluorescence tests are used to confirm the specific diagnosis. Since diagnosis and management of an autoimmune bullous disease may involve systems other than the skin, coordination by the primary care physician is crucial.

Autoimmune Diseases↗
PubMed1996

State of dermatology training: the residents' perspective.

Changes in health care delivery necessitate modification in dermatology training. While the residents at The University of Alabama at Birmingham were planning their 1995-1996 curriculum, several questions regarding the most appropriate allocation of time and resources arose. Interest in other residency curricula prompted the development of a national survey of dermatology residents. Our purpose was to provide comprehensive data regarding the didactic, clinical, surgical, and other aspects of today's U.S. dermatology residency training from the perspective of the residents. It is hoped these data will assist dermatology residency programs with evaluation of their current curricula. A comprehensive 31-question multiplechoice survey was mailed to 631 residents in 70 U.S. dermatology residency programs. Results were tabulated and median values and percentages of responses were obtained. A Wilcoxon rank-sum test, a chi-square analysis, and logistic regression analysis were performed on survey items on the basis of residents' satisfaction with the training program. Two hundred forty-eight responses (39%) were returned with all years of training well represented. Median values and percentages obtained outlined the didactic, clinical, surgical, and other aspects of dermatology residency training. Seventeen percent of residents believed they were not being adequately trained. Satisfaction with training was noted with more didactic faculty involvement, consultations and research, and surgical procedures performed per month. Residents with enriched didactic, clinical, and surgical training experiences are more satisfied with their training programs.

Alabama↗
PubMed1993

Double gloving and surgical technique.

A comparison of double gloving versus single gloving was made with regard to its effects on tactile discrimination and dexterity in 17 surgeons of all grades and specialties. Surgeons were assessed by their ability to tie surgical knots, and Dellon's moving two-point discrimination test. Tests were performed single gloved, double gloved with the larger glove on the outside, and double gloved with the larger glove on the inside. Double gloving did not alter two-point discrimination or the ability to tie surgical knots in this study. Wearing the smaller glove on the outside of the larger glove was considered more comfortable than the conventional technique.

Attitude of Health Personnel↗
PubMed1990

How much processing do nonattended stimuli receive? Apparently very little, but....

The early versus late selection issue in attention models was examined by means of a new methodology. Through cues or precues, attention was directed to one location of a multistimulus visual display and, while attention was so engaged, the identity of a stimulus located at a different position in the display was changed. By varying the time after display onset before the stimulus was changed, we controlled the preview time that the original stimulus was represented on the retina. Then, using a marker cue, we directed the subject's attention to the location of the changed stimulus. The subject's response was a timed discrimination between two possible target letters. The data of main interest was the effect of preview time upon the subject's latency in identifying the new target that appeared in the changed location. We found that the preview time of the original stimulus, before RT was affected to the new target, depended upon whether the original stimulus was a neutral (noise) letter or whether it was the alternative target. When the original stimulus was a noise letter, RTs to the new target were just as fast as those obtained in the control condition in which the target was present throughout the preview interval and did not change its identity. Significant effects upon RT were obtained at preview times of 83 msec when the original stimulus was one of the targets that changed to the alternative target. Preview times also varied as a function of precuing. Preview times were correspondingly shortened when the first cue occurred 50 msec before display onset, thus providing an extra 50 msec for attention to be directed to the first display location. The results were interpreted in terms of two separate information-processing systems in the human: an automatic system and an attentional system. Even though a stimulus may have been automatically processed, when the attention system is directed to that stimulus, processing starts at the beginning again.

Adult↗