A retrospective evaluation of polyurethane, long-stay, peripheral venous cannulae in dogs undergoing radiotherapy.

OBJECTIVES: The aim of this retrospective study was to review placement duration and associated complications of long-stay, peripheral venous cannulae in dogs undergoing a radiotherapy protocol. Factors affecting duration of stay of the cannulae were evaluated. METHODS: The records of patients which had a single-lumen, 16-gauge, 16-cm polyurethane cannulae inserted into a peripheral vein between 2010 and 2014 were reviewed. RESULTS: Forty-one cannulae were placed in 41 patients. Median duration of cannula stay was 14 days (range 2 to 26). In 14 cases (~34%) the cannula was removed at the end of the radiotherapy course. In 13 (~32%) cases, cannula-related complications resulted in premature removal. Use of steroids and antibiotics appeared to be associated with a longer median duration of stay. CLINICAL SIGNIFICANCE: No life-threatening complications were encountered. Indwelling, polyurethane, saphenous cannulae were an effective and safe way to maintain venous access in this group of patients. Prednisolone and antibiotics were typically commenced for acute radiation side effects -midway through the protocol; therefore their association with length of stay may not be a direct result of their administration.

Nursing assessment and responsibilities in monitoring the preterm pregnancy.

Evaluating women for pregnancy-related problems that may result in preterm birth frequently requires electronic fetal monitoring at early gestational ages. Caution is needed to interpret information correctly from the preterm fetal heart rate and uterine activity tracings. Interpreting fetal heart rate tracings from preterm fetuses requires knowledge of fetal physiologic development. Obtaining clear tracings of preterm uterine activity remains a challenge and heightens the importance of thorough nursing assessment, including inquiry about risk factors for pregnancy complications.

Illness severity and costs of admissions at teaching and nonteaching hospitals.

This research examined the hypothesis that greater severity of illness explains the higher costs of hospitalizations at teaching compared with nonteaching hospitals. Medical records of 4439 cases within eight common conditions were reviewed at five tertiary teaching, five other teaching, and five nonteaching hospitals in metropolitan Boston, Mass. We assessed acute physiologic status, severity of the principal diagnosis, comorbidities, and functional status. The principal diagnosis was more severe for teaching hospital patients in four conditions, but few significant differences were found for the other severity dimensions by condition. Across all conditions combined, except for functional status, severity was significantly higher at teaching hospitals, but the absolute differences were small. After adjusting for diagnosis related groups, costs were higher at tertiary teaching compared with other teaching and nonteaching hospitals. Further adjusting for severity and other patient characteristics explained 18% (90% confidence interval, 4 to 33) of the higher costs at tertiary compared with nonteaching hospitals.

The relationship of oral contraceptive use to rheumatoid arthritis.

Current use of oral contraceptives among 71 women aged 17 to 45 diagnosed for the first time as having definite or probable rheumatoid arthritis at Group Health Cooperative of Puget Sound was compared with oral contraceptive use among matched controls. Twenty-three percent of cases and 13% of controls were current users of oral contraceptives at the index date (relative risk estimate = 2.0, 95% CI = 0.97-4.21). We conclude that current oral contraceptive use was not protective against the development of rheumatoid arthritis in this population.

PIP: A possible association between oral contraceptive (OC) use and rheumatoid arthritis was investigated in the 71 women aged 17-45 years of age enrolled at Washington's Group Health Cooperative who were newly diagnosed with this condition in the period 1977-86. 280 matched controls were randomly selected for the Cooperative's file of pharmacy users. Among women with rheumatoid arthritis, 16 (23%) were current OC users, 10 (14%) were past users, and 45 (63%) were never-users. Among controls, 37 (13%) were current users, 44 (16%) were past users, and 203 (71%) were never-users. The relative risk of rheumatoid arthritis was 2.0 (95% confidence interval, 0.97-4.2) in current OC users compared with never-users. The relative risk for past use compared with never-use was 1.0 (0.4-2.2). The duration of OC use or the OC's estrogen content did not have a significant impact on the risk of rheumatoid arthritis. These findings suggest that there is no association between OC use and rheumatoid arthritis and contradict earlier studies that found OC use to exert a protective effect on the development of rheumatoid arthritis. The only factor identified as predictive of a new diagnosis of rheumatoid arthritis was pregnancy completion within the past 24 months (relative risk, 4.1; 95% confidence interval, 1.5-11.2).

Coding of acute myocardial infarction. Clinical and policy implications.

STUDY OBJECTIVE: To evaluate the appropriateness of diagnostic coding of acute myocardial infarction across teaching and nonteaching hospitals. DESIGN: Retrospective review of a random sample of medical records to find evidence of the occurrence and active treatment of acute myocardial infarction during the admission. SETTING: Five tertiary teaching, five other teaching, and five nonteaching hospitals in metropolitan Boston. CASES: Random sample of hospital admissions assigned a discharge diagnosis of acute myocardial infarction between October 1984 and September 1985. MEASUREMENT AND MAIN RESULTS: Of the 1003 cases reviewed, 260 did not meet the clinical criteria for acute myocardial infarction. At tertiary hospitals, 175 (41.7%) failed to qualify, compared with 25 (9.1%) at nonteaching facilities. In a large fraction of the disqualified cases, the patients had been admitted to exclude the diagnosis of acute myocardial infarction; although explicitly "ruled out," an acute myocardial infarction code was assigned. Sixty-six cases from teaching hospitals did not qualify because the patient had been admitted only for coronary angiography after an uneventful postmyocardial infarction course. Almost one-third of these patients had had their infarcts from 5 to 8 weeks before the angiography admission. CONCLUSIONS: Cases with an inappropriate discharge diagnosis of acute myocardial infarction may be concentrated in teaching hospitals. This finding could have implications for Medicare's diagnosis-related group payment system and governmental and other research efforts that use these data for such purposes as drawing inferences about the quality of hospital care.

Apparent sensitivity of human K lymphocytes to the spatial orientation and organization of target cell-bound antibodies as measured by the efficiency of antibody-dependent cellular cytotoxicity (ADCC).

Although monoclonal antibodies (mAb) can elicit potent ADCC by human K lymphocytes, different mAb, even of the same antibody subclass or even of the same target antigen specificity, vary considerably as to their efficiency in eliciting ADCC. The extensive variability in ADCC efficiencies of murine IgG2a mAb is analyzed here. In cold-target inhibition experiments it was found that only cells coated with "ADCC-efficient" IgG2a mAb, and not "ADCC-inefficient" IgG2a mAb, inhibit K effector cell lysis of radiolabeled target cells by ADCC. This result indicates that the spatial orientation of the antibodies on the target cell membrane influences the net efficiency of ADCC reactions by affecting the efficiency of interaction between antibody and the Fc receptors (FcR) of K cells. It is proposed that a "favorable" orientation of antibodies on the target cell membrane is required for efficient ADCC reactions. This proposal is directly supported by the observation that one IgG2a mAb (20.8.4), which cross-reacts with several different H-2 alloantigens, was found to elicit efficient ADCC only when bound to certain of its possible target cell antigens. It was also observed in these studies that the organization of antibodies on a target cell membrane influences the net efficiency of ADCC reactions. It is proposed that a "favorable" antibody organization on the target cell membrane is also required for efficient ADCC reactions. This proposal is supported by the observation that certain antihuman beta 2m (anti-Hu beta 2m) IgG2a mAb, which elicit efficient ADCC lysis of human target cells, fail to elicit the lysis of murine cells having Hu beta 2m molecules coupled randomly to their external membrane surfaces. The differences in the way the Hu beta 2m was organized on the surfaces of the human cells and the murine-Hu beta 2m cell conjugates presumably caused differences in the way the bound antibodies were organized on the cell surfaces, which in turn resulted in the ADCC efficiency differences observed for the same mAb with the different target cell types. Because ADCC reactions appear to be sensitive to both the orientation and the organization of cell surface-bound antibodies, certain types of structural alterations or variations in the membrane molecules (relative to other neighboring structures on the target cell membrane) are potentially detectable by quantitative differences or variations in ADCC reactions.

Evidence of only one H-2D/L-related glycoprotein in H-2dm1 mutant cells.

Analyses of the H-2D/L-related glycoproteins from dm1 mutant cell extracts by sequential immunoprecipitation, by SDS gel electrophoresis and by tryptic peptide mapping indicate that dm1 cells express only a single glycoprotein with H-2D/L-related determinants. In contrast to the four H-2D/L-related antigens identified for the parental d haplotype viz. H-2Dd, H-2Md, H-2Ld and H-2Rd, separate and distinguishable "H-2Ddm1", "H-2Mdm1", "H-2Ldm1" and "H-2Rdm1" glycoprotein counterparts are apparently lacking in the dm1 mutant haplotype. Only a single H-2D/L-related glycoprotein is identified in dm1 extracts by standard serological methods and this glycoprotein is designated H-2D/Ldm1 because of its H-2Dd/H-2Ld hybrid characteristics, as recently shown by Burnside and colleagues (1984). Thus, the seemingly complex phenotype of the dm1 mutant appears to originate primarily from one molecule having properties of two (or more) molecules of the parental haplotype.

Rapid covalent coupling of proteins to cell surfaces: immunological characterization of viable protein-cell conjugates.

A rapid and efficient 2-step procedure is described for covalently attaching proteins to cell surfaces by using a heterobifunctional cross-linking agent, succinimidyl-4-(N-maleimidomethylcyclohexane)-1-carboxylate (SMCC). In the first step, protein is derivatized for about 30 min with a 1:1 (mole:mole) stoichiometric ratio of SMCC which creates 4-(N-maleimidomethylcyclohexane)-1-amidyl-protein (MCA-protein) covalent linkages with the primary amino groups of proteins. In the second step, cell-MCA-protein conjugates are rapidly prepared (in less than 30 min) by reacting MCA-protein with 'reduced' cells which have been pre-incubated (for about 1 h) with dithiothreitol (DTT). Stable protein-cell conjugates result from the covalent thioether linkages formed between the maleimido groups of the derivatized protein and the cell surface thiol groups created by DTT reduction. Protein-cell conjugates have been made in this way with several different proteins using several different types of cells. Such conjugates are characterized in this study by complement plus antibody-mediated cytotoxicity (CAMC) and by antibody-dependent cellular cytotoxicity (ADCC) with human effector lymphocytes. Because these protein-cell conjugates are shown to remain viable and to retain significant levels of coupled protein for at least 24 h in culture, they are potentially useful for probing various membrane-related phenomena such as the recognition of cell surface antigens by immune effector cells.

Breast cancer in mothers given diethylstilbestrol in pregnancy.

We compared the incidence of breast cancer in 3033 women who had taken diethylstilbestrol (DES) in pregnancy during the period from 1940 to 1960 with the incidence in a comparable group of unexposed parous women. We ascertained vital status in 95 per cent of the exposed women and in 93 per cent of the unexposed women and received completed questionnaires for 88 and 85 per cent, respectively. With over 85,000 woman-years of follow-up in each group, the incidence of breast cancer per 100,000 woman-years was 134 in the exposed group and 93 in the unexposed group, yielding a crude relative risk of 1.4 (95 per cent confidence interval, 1.1 to 1.9). The elevated incidence did not appear to be due to bias or to confounding by other risk factors measured in the study. Breast-cancer mortality was slightly higher in the exposed women (relative risk, 1.1) but not significantly so (95 per cent confidence interval, 0.7 to 2.0). We conclude that the incidence of breast cancer is moderately increased in women given DES, but we cannot exclude the possibility that some unrecognized concomitant of DES exposure accounts for this increase.

PIP: The authors compared the incidence of breast cancer in 3033 women who had taken diethylstilbestrol (DES) in pregnancy during the period 1940-60 with the incidence in a comparable group of unexposed parous women. The vital status was ascertained in 95% of the exposed women and in 93% of the unexposed women and completed questionnaires were received for 88 and 85% respectively. With over 85,000 women-years of follow-up in each group, the incidence of breast cancer/100,000 woman-years was 134 in the exposed group and 93 in the unexposed group, yielding a crude relative risk of 1.4 (95% confidence interval, 1.1-1.9). The elevated incidence did not appear to be due to bias or to confounding by other risk factors measured in the study. Breast cancer mortality was slightly higher in the exposed women (relative risk, 1.1) but not significantly so (95% confidence interval, 0.7-2.0). The incidence of breast cancer is moderately increased in women given DES, but the possibility cannot be excluded that some unrecognized concomitant of DES exposure accounts for this increase.

A molecular hybrid of the H-2Dd and H-2Ld genes expressed in the dm1 mutant.

Sequential immunoprecipitates show that H-2dm1 mutant cells express a hybrid "H-2D/L" antigen exhibiting determinants normally associated with two different gene products of the parental d haplotype-i.e., the H-2Dd and H-2Ld antigens. The hybrid H-2D/Ldm1 antigen appears to consist of a portion of the NH2-terminal extracellular half of the H-2Dd antigen "fused" to a portion of the COOH-terminal extracellular half of the H-2Ld antigen. This structure is inferred from the reactivity of dm1 antigens with cytotoxic T lymphocytes specific for H-2Ld determinants and with monoclonal antibodies specific for determinants in the structural domains of H-2Ld or H-2Dd. The H-2D/Ldm1 molecule apparently retains all of the third external domain (C2 or alpha 3) and part of the second external domain (C1 or alpha 2) of H-2Ld, but its first external domain (N or alpha 1) derives from H-2Dd. From these findings and from previous peptide mapping studies, we propose that the H-2D/Ldm1 antigen is the product of a hybrid gene that has resulted from an unequal crossover between the parental H-2Dd and H-2Ld genes, leaving the N exon and part of the C1 exon of the H-2Dd gene joined to the H-2Ld gene beginning somewhere within its C1 exon.