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B Bass

Publications and source records attributed to B Bass.

At least 19 recordsLinked to original sources
PubMed2001

Comparison of surgical outcomes between teaching and nonteaching hospitals in the Department of Veterans Affairs.

OBJECTIVE: To determine whether the investment in postgraduate education and training places patients at risk for worse outcomes and higher costs than if medical and surgical care was delivered in nonteaching settings. SUMMARY BACKGROUND DATA: The Veterans Health Administration (VA) plays a major role in the training of medical students, residents, and fellows. METHODS: The database of the VA National Surgical Quality Improvement Program was analyzed for all major noncardiac operations performed during fiscal years 1997, 1998, and 1999. Teaching status of a hospital was determined on the basis of a background and structure questionnaire that was independently verified by a research fellow. Stepwise logistic regression was used to construct separate models predictive of 30-day mortality and morbidity for each of seven surgical specialties and eight operations. Based on these models, a severity index for each patient was calculated. Hierarchical logistic regression models were then created to examine the relationship between teaching versus nonteaching hospitals and 30-day postoperative mortality and morbidity, after adjusting for patient severity. RESULTS: Teaching hospitals performed 81% of the total surgical workload and 90% of the major surgery workload. In most specialties in teaching hospitals, the residents were the primary surgeons in more than 90% of the operations. Compared with nonteaching hospitals, the patient populations in teaching hospitals had a higher prevalence of risk factors, underwent more complex operations, and had longer operation times. Risk-adjusted mortality rates were not different between the teaching and nonteaching hospitals in the specialties and operations studied. The unadjusted complication rate was higher in teaching hospitals in six of seven specialties and four of eight operations. Risk adjustment did not eliminate completely these differences, probably reflecting the relatively poor predictive validity of some of the risk adjustment models for morbidity. Length of stay after major operations was not consistently different between teaching and nonteaching hospitals. CONCLUSION: Compared with nonteaching hospitals, teaching hospitals in the VA perform the majority of complex and high-risk major procedures, with comparable risk-adjusted 30-day mortality rates. Risk-adjusted 30-day morbidity rates in teaching hospitals are higher in some specialties and operations than in nonteaching hospitals. Although this may reflect the weak predictive validity of some of the risk adjustment models for morbidity, it may also represent suboptimal processes and structures of care that are unique to teaching hospitals. Despite good quality of care in teaching hospitals, as evidenced by the 30-day mortality data, efforts should be made to examine further the structures and processes of surgical care prevailing in these hospitals.

Education, Medical, Graduate↗
PubMed1999

Marital interaction in dyadic and triadic contexts: continuities and discontinuities.

While the systemic metaphor used in much current family research requires examination of the interrelationships among individuals, relationships, and the family as a whole, work on triadic relationships has generally been missing. This research examined the presence of second-order effects in marital interaction: changes in interactions between spouses when the husband-wife dyad became a parent-parent-child triad. Results indicated the presence of consistent context effects. Parental behavior when alone was not a good predictor of parental behavior in the presence of a child: behaviors occurred at significantly lower levels in parental dyads than in parent-parent-child triads, and correlations across the two contexts were less than consistent. Results are discussed in light of their implications for observations of families.

Adult↗
PubMed1998

Role of insulin-like growth factor-I (IGF-I) receptor, IGF-I, and IGF binding protein-2 in human colorectal cancers.

The identification of novel autocrine/paracrine signaling pathways and possible markers represents an important component in the understanding of tumor growth control. In this study, we assessed the potential role of insulin-like growth factor-I (IGF-I), the IGF-I receptor (IGF-IR) and IGF binding protein-2 (IGFBP-2) in human colorectal cancer. Initial studies demonstrating increased IGF-I binding and IGF-IR density in human colon cancer tissue revealed that a component of iodinated (3-[125-I]iodotyrosyl) IGF-I (125I-ICGF-I) binding was not attributable to IGF-IR. Binding studies and Western blot analysis suggested that this second component of 125I-IGF-I binding could be due to IGFBP-2. Further analysis by a specific solution hybridization/RNase protection assay for IGF-IR mRNA levels, IGFBP-2 mRNA levels and in situ hybridization for IGFBP-2 localization, was carried out in nine patients with colon cancer. IGF-IR mRNA levels by RNAse protection assays were unchanged, whereas IGFBP-2 mRNA levels were increased 4-8-fold in patients with colon cancer compared to controls. Three patients with Dukes stage C disease had the highest levels of IGFBP-2 mRNA. In situ hybridization studies localized IGFBP-2 mRNA to malignant cells and not to the surrounding stromal cells, suggesting an autocrine role for IGFBP-2. The discrepancy between increased IGF-I binding, IGF-IR density, IGFBP-2 mRNA and the minimal modulation of the IGF-IR mRNA implies post-transcriptional regulation of IGF-IRs. Our results suggest that IGFBP-2 may be implicated in colon cancer metastases and prognosis. Its usefulness as a potential tumor marker should be further investigated.

Autoradiography↗
PubMed1997

Breast screening.

Explore the source record for details and available documents.

Attitude of Health Personnel↗
PubMed1995

Ketorolac versus meperidine-plus-promethazine treatment of migraine headache: evaluations by patients.

This study was designed to compare and contrast the speed and efficacy of meperidine (75 mg)/promethazine (25 mg) intramuscularly to ketorolac (60 mg) intramuscularly, in a double-blind study in reducing the symptoms of migraine headache. Forty-two patients who presented to the emergency department between July 1992 and February 1993, with previous diagnoses of migraine headache, were considered for this study. Patients subjectively evaluated parameters of their migraine headaches (eg, pain and nausea) using a numeric scale and were later asked to reevaluate these same parameters at 30, 60, and 360 minutes after a single intramuscular injection of either ketorolac (60 mg) or meperidine (75 mg)/promethazine (25 mg). Sixty-eight percent of patients given meperidine/promethazine responded whereas 55% of patients given ketorolac responded. The responder group showed a statistically significant reduction in headache within 30 minutes with both drug regimens. There was no statistically significant difference between the number of responders in either group. The responders from both groups had relief that lasted 6 hours after injection. In the nonresponder groups, most of the patients withdrew within 1 hour after treatment. As determined by patient response to treatment of their migraine headaches, there was no statistically significant difference between the ketorolac and the meperidine/promethazine groups.

Adult↗
PubMed1994

Contradictions in women's health care provision: a case study of attendance for breast cancer screening.

Breast cancer screening facilities operated by the Ontario Breast Screening Program (OBSP) have recently been added to the existing geography of diagnostic mammography facilities in hospitals and private clinics in Eastern Ontario. While diagnostic facilities require a physician's referral for access, the new centres offer mammograms by self-referral. Other work has shown the utilization of mammography screening services to be quite low despite widespread acceptance of early diagnosis through mammographic screening as the best method to lower breast cancer mortality. Major findings are that spatial variation does exist in attendance rates in the townships and census tracts surrounding the screening centre. At the regional level, physician referral patterns and the presence of local diagnostic mammography units appear to affect the uptake of screening at the Kingston facility. The individual level analysis confirms the importance of the primary care physician's referral with two-thirds of the client sample indicating that they were referred for screening by their family physician. The sample of clients are also very mobile women who have comparatively greater access to financial resources than other women of screening age. The results of ecological and individual level analyses of attendance at OBSP's Kingston Centre reveal contradictions in the provision of this service. Spatially, the centres follow a location pattern of a much higher order health facility yet women are expected to include screening as part of their routine care. Attenders at the Centre were found to be of higher socioeconomic status, married and have access to a private automobile. The finding that the primary care physician's referral is an important prerequisite for attendance raises questions about the feasibility of providing health care for women which encourages individual responsibility for health within the existing paternalistic health care system.

Aged↗
PubMed1994

Recruitment for breast screening in a rural practice. Trial of a physician's letter of invitation.

OBJECTIVE: To evaluate a systematic effort to recruit women for breast screening. DESIGN AND SETTING: Individually addressed letters, signed by the woman's physician (followed by reminder letters and telephone calls as necessary) were sent to women in a rural family practice, prompting them to make an appointment for breast screening at the Ontario Breast Screening Program-the Kingston Centre. PARTICIPANTS: Women were eligible to receive a letter if they were aged 50 to 69, had not had a mammogram for at least 12 months, and did not have a previous diagnosis of breast cancer or current acute symptoms of breast disease. MAIN OUTCOME MEASURES: Response rates were measured to the initial letter, the reminder letter, and the telephone call. Women who came to the breast screening centre as a result of this recruitment effort were surveyed on their reaction to the letter. RESULTS: The response rate, as measured 9 months after the initial letters were sent, was 57.5%; 38% of respondents to the initial letter and 49% of respondents to the reminder letter said they would not have come to the centre without the letter. Both the breast screening program managers and the family physicians involved considered the project a success. CONCLUSION: Integrating with an organized breast screening program is one way for busy family physicians systematically to involve their patients in an early detection program without unduly burdening physicians or disrupting normal patient care.

Aged↗
PubMed1993

Ketorolac as a rapid and effective treatment of migraine headache: evaluations by patients.

The objective of this study was to determine the speed and efficiency of ketorolac in reducing the symptoms of migraine headache. Twenty-three patients who presented in the emergency department during the period between April and July 1992 with a previous diagnosis of migraine headache were considered for the study. Patients subjectively evaluated parameters of their migraine headaches (eg, pain and nausea) with a numerical scale and were asked to re-evaluate these same parameters at 30, 60, and 360 minutes after a single injection of Ketorolac. Seventeen (74%) patients reported a decrease in headache symptoms that was significant (P < .005) after 1 hour. Relief lasted at least 6 hours after injection.

Acute Disease↗
PubMed1992

A double-blind, randomized, crossover trial of pemoline in fatigue associated with multiple sclerosis.

Fatigue occurs in a majority of patients with MS and is generally independent of measurable neurologic disability. Few options for treatment are available. We conducted a double-blind, placebo-controlled, crossover trial for each of two 4-week treatment periods. Forty-six eligible patients entered and five dropped out due to concurrent exacerbations. Nineteen patients (46.3%) experienced excellent or good relief of fatigue with pemoline, and eight patients (19.5%) with placebo (p = 0.06, Fisher's exact test). One-fourth of patients did not tolerate the drug well, and 7% had to discontinue pemoline during the study due to side effects. The most common side effects were anorexia, irritability, and insomnia. Pemoline may be an effective short-term treatment for fatigue associated with MS, but its adverse effects are not well tolerated by many patients.

Adult↗
PubMed1991

Tat-dependent adenosine-to-inosine modification of wild-type transactivation response RNA.

Tat is a potent activator of gene expression in human immunodeficiency virus type 1 (HIV-1). Activation by Tat requires a cis-acting element, the transactivation response (TAR) site, located in the viral long terminal repeat and the 5' end of all viral mRNAs. Sequences in TAR RNA can fold into a specific stem-loop structure, and certain features of the stem-loop are essential for Tat-mediated transactivation. In Xenopus oocytes, TAR sequences can inhibit the translation of 3' cis-linked mRNAs. However, coinjection of Tat and the TAR-containing RNA into oocyte nuclei relieves this translational inhibition [Braddock, M., Chambers, A., Wilson, W., Esnout, M. A., Adams, S.E. & Kingsman, S.M. (1989) Cell 58, 269-279]. We report here that the intramolecular TAR stem-loop structure is a substrate for the double-stranded RNA (dsRNA)-modifying activity, which converts adenosines to inosines. This activity is located in the nuclei of Xenopus oocytes. The specificity and extent of modification of adenosines in TAR is dependent on Tat. We propose that the dsRNA-modifying activity may be one of the cellular proteins that interacts with TAR in the nucleus. The possible role of TAR RNA modification in the expression of HIV-1 is discussed.

Adenosine↗
PubMed1991

PEG ileus. A new cause of small bowel obstruction.

A case of small bowel obstruction due to a lodged percutaneous endoscopic gastrostomy tube inner bumper is described. Most probably inner bumper lodgement in the terminal ileum is related to its size. Laparotomy was required to remove the bumper and relieve the obstruction. We suggest that all percutaneous endoscopic gastrostomy bumpers be retrieved endoscopically when the PEG tube is removed or replaced unless a collapsible inner bumper is used.

Aged↗
PubMed1991

An open trial of OKT3 in patients with multiple sclerosis.

We report our experience with treatment with Muromonab-CD3 (Orthoclone OKT3) of 16 patients with multiple sclerosis (MS) who were in a progressive phase of their disease (n = 13) or in an acute severe attack lasting longer than 1 month without recovery (n = 3). We induced acute severe T-cytopenia with OKT3. Fifteen patients completed treatment for 10 days. Side effects were common and severe and included hypotension, nausea and vomiting, diarrhea, fever, and myalgia. In two of two patients tested, there was a transient though major rise in the levels of interferon gamma and tumor necrosis factor in the first 12 hours of treatment. Nonetheless, we did not detect new clinical or MRI activity of MS during the period of treatment, although many patients deteriorated transiently in disability scores. At the conclusion of follow-up, only four patients had deteriorated by 1.0 or more points on the Expanded Disability Status Scale of Kurtzke (EDSS) (73% stabilization rate). Of those patients who deteriorated, two died of complications of MS (EDSS 10). Only two patients had clinical improvement at 1 year follow-up. The attendant toxicity of OKT3 makes it unlikely that it will play a major role in the treatment of MS.

Antibodies, Monoclonal↗
PubMed1990

Preclinical evaluation of immunoconjugates consisting of doxorubicin linked to complement-fixing monoclonal antibody DLC-48 for bone marrow purging of B-cell lymphomas.

Complement-fixing monoclonal antibody DLC-48 was linked covalently to doxorubicin using two methodologies, and the resulting conjugates were evaluated for their usefulness in purging B-cell lymphomas from human bone marrow autografts using a clonogenic assay for the large cell lymphoma cell line SU-DHL-4. Conjugation did not impair the reactivity of the antibodies. The resultant molar ratios provided for maximal immunoreactivity at doxorubicin concentrations that would permit the growth of CFU-GM. Conjugate DLC-48D-G retained its complement-fixing capacity, and was more cytotoxic to SU-DHL-4 cells, even in the absence of complement, than equivalent doses of doxorubicin. This effect appeared to be non-specific, in that CFU-GM were eliminated, even at low concentrations. DLC-48D-G was no more effective than equivalent doses of doxorubicin, and equally cytotoxic to CFU-GM. Mixtures of unconjugated DLC-48 and doxorubicin, however, were more effective than doxorubicin alone. The mechanism of action of these conjugates is under study. Alternative methods of conjugation will be investigated.

Animals↗
PubMed1989

Distribution of vasoactive intestinal polypeptide and substance P receptors in human colon and small intestine.

Vasoactive intestinal polypeptide (VIP) and substance P are found in neurons in the lamina propria and submucosa and muscularis propria of human small intestine and colon. VIP receptors coupled to adenylate cyclase are present on epithelial, smooth muscle, and mononuclear cells. This study analyzes the distribution of [125I]VIP binding and [125I]substance P in human colon and small intestine using autoradiographic techniques. [125I]VIP binding was present in high density in the mucosal layer of colon and small intestine. [125I]VIP binding was not significantly greater than nonspecific binding in smooth muscle layers or the lymphoid follicles. In contrast, [125I]substance P binding was present in high density over the colonic muscle but was not present over the mucosal layer. In human colon cancer, [125I]VIP grain density over the malignant tissue was only slightly higher than background. These autoradiographic studies of [125I]VIP binding indicate that the highest density of VIP receptors was found in the small intestine and superficial colonic mucosa, whereas the density of substance P receptors was highest over the smooth muscle layers. These findings suggest a mismatch between immunochemical content of the peptide and autoradiographic density of the receptor.

Autoradiography↗
PubMed1989

The elimination of malignant B lymphocytes from human bone marrow using monoclonal antibodies DLC-48 and LN-1 and human serum: a preclinical study.

Monoclonal antibodies DLC-48 and LN-1 were evaluated for use in purging malignant lymphoma cells from human bone marrow. Using a 51Cr-release assay and sensitive clonogenic assay for the SU-DHL-2 and -4 cell lines, it was established that greater than four logs of malignant lymphoid cells can be eliminated from human bone marrow autografts with three treatments of antibody and autologous human serum at a final cell concentration of 1 X 10(7) cells/ml. A combination of DLC-48 and LN-1 was more effective than either antibody alone. Treatment with antibody and autologous serum had no effect on the growth of human hematopoietic progenitor cells. The clinical effects of marrow treatment with DLC-48 and LN-1 will be evaluated in upcoming clinical trials.

Animals↗
PubMed1989

The natural history of multiple sclerosis: a geographically based study. I. Clinical course and disability.

The outcome of multiple sclerosis (MS), assessed according to the Kurtzke Disability Status Scale (DSS), was reviewed in 1,099 consecutive patients followed in London, Canada, between 1972 and 1984. A geographically based subgroup of 196 patients representing 90% of Middlesex County MS patients as well as a group of 197 patients seen from onset of disease were separately analysed. The clinical course was progressive from onset in 33% of the total population and in 28% of the Middlesex County subgroup. Of those with duration of 6-10 yrs, 30-40% with initially remitting disease developed progressive MS. The cross-sectional distribution of disability was bimodal with peaks at DSS 1 (no disability) and DSS 6 (assistance required for walking). Actuarial analysis showed that the median time to reach DSS 6 from onset of MS was 14.97 +/- 0.31 yrs in the total population and 9.42 +/- 0.44 yrs in the "seen from onset' subgroup. Survival was minimally altered; 87% of patients followed up to 40 yrs were still alive, although ascertainment of cases with this duration of MS was incomplete. Data describing the rate at which disability develops after the onset of a progressive phase of MS are also presented. The implications of these data in planning and interpretation of clinical therapeutic trials are discussed.

Canada↗
PubMed1989

The natural history of multiple sclerosis: a geographically based study. 2. Predictive value of the early clinical course.

Controversy exists regarding the predictive value of the early clinical course of multiple sclerosis (MS). Three parameters often considered are the attack rate, the first interattack interval and the rate at which disability develops in the early years of the disease. We have recorded the time to reach successive levels of disability defined by the Kurtzke Disability Status Scale (DSS) in 1,099 MS patients followed at University Hospital, London, Canada between 1972 and 1984. Our population is particularly suitable because of its size, the high degree of ascertainment of cases in the community, and the regular follow-up provided. Life table analysis was used to compare survival in patients stratified according to the above three parameters using DSS 6 as end point. Significant differences were evident in the survival distributions. Despite the extensive interindividual variation in the rate at which disability developed, the early course of MS may be useful in determining the relative risk of rapid progression.

Disability Evaluation↗