Biomedical subjects
Publications and source records attributed to J Adams.
The proteasome is not simply a 'garbage disposal unit' but also has functions in the control of the cell cycle and immune responses. The structure of an archaebacterial proteasome has recently been determined to high resolution, and provides insight into the unusual mechanism of proteolytic cleavage by the proteasome.
Bone density measurements by dual X-ray absorptiometry (DXA) of the spine can now be made precisely, but there is no uniformity in reporting results and in presenting reference data. A European Union Concerted Action therefore devised a uniform procedure for cross-calibrating and standardizing instruments, using the European spine phantom (ESP) prototype. This phantom differs in a number of respects from the final version of the ESP. Eighteen centers in nine countries obtained 1619 records (1035 women) from Caucasian subjects, aged 20-80 years, drawn from normal populations. The DXA machines used were made by the Hologic, Lunar, and Norland companies. Highly statistically significant differences were evident between populations, both in apparent rates of bone loss with age and in the spread of values about the age-adjusted means. There were small residual differences in the results obtained with the three machine brands which could have been due to the relatively large between-center population differences we observed. The alternative or additional explanation that they were attributable, in part, to the design differences between the ESP prototype and the definitive ESP, which became available after this study was completed, was shown to be a valid possibility. Results from postmenopausal women reported in relation to the years that have elapsed since menopause showed reduced population variance when compared with conventional reporting in relation to age. After cross-calibration, the center with the highest age-adjusted normal density value averaged 23% more than the center with the lowest. It is therefore crucially important to select appropriate reference data in clinical and epidemiological studies.(ABSTRACT TRUNCATED AT 250 WORDS)
We present a case of bladder augmentation with stomach, via a laparoscopic approach. The patient was a 17-year-old girl with sacral agenesis and a poorly compliant bladder. A wedge of stomach, based on the right gastroepiploic pedicle, was obtained using a stapled technique. The bladder was opened and the gastric segment was sutured in place. A needle suspension was also carried out. Three months later, the patient was dry and catheterizing every 4 hours. Laparoscopic bladder augmentation is technically feasible and, in the properly selected patient, may be the preferred technique for creation of a compliant high-volume urinary reservoir.
OBJECTIVE: To evaluate the process and outcome of outpatient consultative geriatric assessment compared with traditional community care. DESIGN: Randomized, controlled clinical trial, with 12-month follow-up. SETTING: Four hospital-based ambulatory geriatric assessment clinics and community physicians' offices. PARTICIPANTS: 442 recruited older adults with a health problem or recent change in health status. INTERVENTION: Outpatient consultative geriatric assessment or usual physician assessment. MAIN OUTCOME MEASURES: Identification of health problems, mortality, nursing home admissions, health status, health services utilization, satisfaction with care, and caregiver well-being. RESULTS: Geriatric assessment, in comparison with usual community care, resulted in the identification of a significantly greater number of patients with cognitive impairment (P < .0001), depression (P = .0004) and incontinence (P < .0001). The group receiving a geriatric assessment had greater improvement in anxiety levels at 1 year (P = .036). Caregivers of participants in the geriatric assessment group had less caregiver stress at 1 year (P = .002). No outcome differences in mortality, nursing home admissions, cognitive health, functional health, or health services utilization were observed. Some evidence of greater patient satisfaction with respect to qualities of the physician was found for the geriatric assessment group. CONCLUSIONS: Consultative outpatient geriatric assessment led to significantly improved diagnosis of the common health problems of cognitive impairment, depression, and incontinence, to psychological and emotional benefits for patients, and to reduced levels of caregiver stress. Even with limited follow-up care and control of treatment, outpatient geriatric assessment has potential for significant positive effects.
Fourteen ambulatory patients with spastic cerebral palsy were evaluated prior to and 6 months following selective dorsal rhizotomy. An instrumented gait analysis identified significant improvements in foot contact patterns, velocity and stride length. The high incidence of postoperative valgus, excessive dorsiflexion and persistent knee flexion during gait was attributed to significant weakness and hypotonicity in the plantar flexors, as well as residual hamstring spasticity (p < 0.05). Sectioning of fewer S-1 rootlets may preserve plantar flexion strength and enhance stance stability by preventing postoperative increases in dorsiflexion and knee flexion. Orthotic prescription for ankle instability should be a routine postoperative consideration.
The authors recently published a meta-analysis of controlled trials of comprehensive geriatric assessment (CGA). The results supported the view that efficacy of CGA is strongly related to the patients, objectives, and basic design of CGA programs, and that particular program models and design features are associated with important health outcome improvements (e.g., survival, living at home, and functional improvement at follow-up). Present objectives include the outline of methods and how they were developed given the condition of the trial database and scientific context. Aspects of the approach, such as (a) survey of primary trialists to recover unpublished information and standardize data, (b) development of a program typology to guide the principal analysis, and (c) incorporation of program design features as covariates where statistical heterogeneity was detected, proved extremely useful, and have implications for other systematic reviews of similarly complex primary trials of new health care technologies, health services, and organizational interventions.
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PURPOSE: To provide paclitaxel, an investigational drug at the inception of this study, to women with chemotherapy-refractory metastatic breast cancer and to evaluate response and toxicity in these patients. PATIENTS AND METHODS: Two hundred sixty-seven patients with progressive disease (PD) following at least two chemotherapy regimens for metastatic breast cancer and a contraindication to further doxorubicin treatment received paclitaxel either at 175 mg/m2 intravenously (IV) over 24 hours or at 135 mg/m2 if they had prior irradiation to 30% of marrow-bearing bone or a cumulative dose of mitomycin > or = 20 mg/m2. RESULTS: In a subgroup of patients (n = 172) with measurable disease, four complete responses (CRs) and 36 partial responses (PRs) occurred, for an overall response rate of 23% (95% confidence interval [CI], 17% to 30%). No differences in response rates were noted according either to the number of prior chemotherapy regimens received or to whether patients were considered refractory to doxorubicin. The dose and schedule used in this trial resulted in febrile neutropenia in 45% of patients and a hospitalization rate of 49%. CONCLUSION: Paclitaxel's activity in this multiinstitutional trial in heavily pretreated patients confirms the encouraging results attained in single-institution trials. Although at this dose and schedule paclitaxel may be considered too myelosuppressive for palliative care, supportive measures such as colony-stimulating factors and antibiotics were not used prophylactically. Current research efforts are focusing on whether paclitaxel's activity against breast cancer is dose- and/or schedule-dependent, and on what role it has in patients with less advanced disease.
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PURPOSE: We attempted to apply laparoscopic orchiopexy to the high palpable testis. MATERIALS AND METHODS: Nine patients (12 testicles) were treated who ranged from 13 months to 13 years old. Laparoscopic techniques were used to mobilize the spermatic vessels and transfer the testis into the scrotum. RESULTS: Unilateral cases were completed in an average of 2.6 hours and bilateral cases in 3.0 hours with no complications. Tests maintained an intrascrotal position with no atrophy during a followup of 1 to 12 months. CONCLUSIONS: Laparoscopic orchiopexy for the high palpable undescended testis is possible with minimal morbidity and good short-term results.
1. The worksite is an emerging and appropriate setting for nurse practitioner provided primary care services. 2. Health risk appraisal has been identified in the literature and in employment settings as a valuable component of a worksite health program. 3. Nurse practitioners can use health risk appraisal, in combination with physical assessment, to target needs of those at high risk for certain health problems and to determine appropriate wellness oriented education and counseling. 4. Further research is needed to determine motivating factors for employees to make changes in high risk behaviors once they are identified through health risk appraisal.
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Recent work by Magnuson, Solomon and Grossman(1) adds to a growing body of evidence indicating that microorganisms possess sophisticated signaling systems that enable them to sense and respond to environmental challenges. Typically, this response results in morphological, physiological and even genetic differentiation, paralleling that observed among higher organisms. These signaling systems may be interpreted as adaptations that maximize the reproductive potential of a population.
The performance of a recently introduced Staphylococcus aureus identification system (Slidex Staph-Kit) was compared with that of currently available systems (Immuno Scan Staphlatex, Staphyloslide, Staphaurex and SeroSTAT II) for the identification of methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-susceptible Staphylococcus aureus. The new system, which detects a capsular antigen common in MRSA, performed with equal or greater sensitivity than the other systems. None of the commercial systems was adversely affected by the methicillin susceptibility of the staphylococci when isolates were recovered from non-selective media. The greatest advantage of the anti-capsular monoclonal reagent was its improved performance on isolates recovered from selective media.
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We have developed a general system, QGB, for performing complex queries on the information in the DDBJ/EMBL/GenBank databases, including queries over the structural features of sequences implied in the FEATURE TABLE. Queries are formed in a Structured Query Language (SQL)-like syntax with language extensions to support complex types (e.g., sets, ordered sets, and records) appropriate for representing and querying sequence data. A novel aspect of QGB is its ability to deduce missing features and infer relationships among features as a consequence of constructing a parse tree of sequence structure from information described in the FEATURE TABLE. The grammar for the parse tree is implemented in a customized form of the Definite Clause Grammar syntax of the logic programming language Prolog. The logic grammar formalism was chosen because it provides a perspicuous representation for features and constraints, and Prolog provides an execution model for the grammar rules. Construction of the parse tree also identifies inconsistencies and errors in the FEATURE TABLE that can in some cases be corrected automatically and used to generate an augmented version of the table.
Populations of Escherichia coli initiated with a single clone and maintained for long periods in glucose-limited continuous culture, become polymorphic. In one population, three clones were isolated and by means of reconstruction experiments were shown to be maintained in stable polymorphism, although they exhibited substantial differences in maximum specific growth rates and in glucose uptake kinetics. Analysis of these three clones revealed that their stable coexistence could be explained by differential patterns of the secretion and uptake of two alternative metabolites acetate and glycerol. Regulatory (constitutive and null) mutations in acetyl-coenzyme A synthetase accounted for different patterns of acetate secretion and uptake seen. Altered patterns in glycerol uptake are most likely explained by mutations which result in quantitative differences in the induction of the glycerol regulon and/or structural changes in glycerol kinase that reduce allosteric inhibition by effector molecules associated with glycolysis. The evolution of resource partitioning, and consequent polymorphisms which arise may illustrate incipient processes of speciation in asexual organisms.
The benefits of thrombolysis are believed to be related to the speed of reperfusion of the infarct-related artery. In this sub-study, evidence for the occurrence of reperfusion before admission to hospital has been sought. In a randomized double-blind controlled trial, 311 patients with suspected acute myocardial infarction were given anistreplase 30 units i.v., either at home at a median 101 min (early group, n = 163), or in hospital at a median 240 min after symptom onset (large group, n = 148). Paired electrocardiograms recorded at home and on admission to hospital were available for study in 143 and 137 patients in early and late groups. Reduction in ST elevation between home and hospital electrocardiograms of > 25% in a single lead was taken as evidence of reperfusion. Patients with significant ST elevation in either electrocardiogram comprised the sub-study groups, and numbered 63/143 (44%) and 68/137 (50%) in early and late groups respectively. A reduction of > 25% in the single lead demonstrating greatest ST elevation on the presenting electrocardiogram was observed in 37/63 (59%) and 23/68 (34%) patients in the early and late sub-study groups (difference 25%, 95% confidence interval 8% to 42%, P = 0.003). It was found that domiciliary thrombolysis was associated with electrocardiographic evidence of an increased rate of reperfusion occurring before admission to hospital. Evidence of reperfusion occurring pre-hospital, whether spontaneous or following thrombolytic therapy, was associated with a better outcome.