Search PubMed⌕ Search

Biomedical subjects

B Anderson

Publications and source records attributed to B Anderson.

At least 217 records · Page 12Linked to original sources

Detection of Rochalimaea henselae in cat-scratch disease skin test antigens.

One of the diagnostic criteria for cat-scratch disease is a positive delayed-type hypersensitivity skin test reaction to an antigen prepared from purulent material aspirated from a cat-scratch disease-involved lymph node. Polymerase chain reaction coupled with DNA sequence analysis was used to identify organisms found in these skin test antigen preparations that may be responsible for eliciting this response. Two independent sources of cat-scratch disease skin test antigens yielded DNA sequences characteristic of the newly described rickettsia, Rochalimaea henselae. These results coupled with previous serologic data strongly suggest that R. henselae plays a central role in the etiology of cat-scratch disease.

Antigens, Bacterial↗

The predictive accuracy of home oximetry in patients with suspected obstructive sleep apnea.

To evaluate the predictive accuracy of home oximetry, we have performed a questionnaire, physical examination and home oximetry on 96 patients with suspected obstructive sleep apnea (OSA) within 2 weeks of laboratory polysomnography. We have developed a predictive equation that includes questionnaire, anthropometric and home oximetry data to diagnose OSA. We could confidently diagnose OSA in 20% of patients and exclude OSA in 5% of patients based on this prediction model and the population distribution.

Adult↗

Monitoring the activity of antiviral therapy for HIV infection using a polymerase chain reaction method coupled with reverse transcription.

AIM: To monitor the anti-HIV-1 activity of antiretroviral agents in patients with HIV-1 infection. METHOD: Quantification of viral RNA copy in plasma or serum using a polymerase chain reaction method coupled with reverse transcription. CONCLUSIONS: The HIV-1 RNA copy number represents the HIV-1 viremia status in patients with HIV-1 infection. This copy number is likely to be useful in monitoring the effectiveness of antiviral therapy and the method is likely to be built into every clinical trial of anti-HIV-1 therapy in the near future.

Antiviral Agents↗

Enzyme-linked immunosorbent assay for detection of human immunoglobulin G to lipopolysaccharide of spotted fever group rickettsiae.

An enzyme-linked immunosorbent assay for detecting human immunoglobulin G to spotted fever group rickettsiae was developed and tested. The assay uses proteinase K-resistant material, characteristic of the rickettsial lipopolysaccharides shown to be group specific by immunoblots, as the antigen. The results indicate that the assay provides a sensitive, yet specific, alternative method for diagnosing rickettsial diseases.

Endopeptidase K↗

Cervical cancer: application of MR imaging in radiation therapy.

PURPOSE: To evaluate magnetic resonance (MR) imaging in the planning of radiation therapy for patients with cervical cancer. MATERIALS AND METHODS: MR imaging was performed in 15 patients with predominantly advanced cervical carcinomas. Skin markings of the radiation ports were labeled with MR-detectable tubing and beads to assess the adequacy of port placement. Volume and extent of tumor at MR imaging were compared with those at physical and computed tomographic (CT) examinations. RESULTS: Tumor involvement of normal structures (parametrium, vagina, endometrium) was more extensive at MR imaging than at clinical examination in six patients (40%) and at CT in five patients (33%), resulting in modification of the radiation fields in eight patients (53%). Tumor size was larger on MR images than at clinical examination in 11 patients (73%). CONCLUSION: MR imaging can depict tumor volume and better delineate the extent of involvement than physical and CT examination. This can be useful for placement of radiation ports, especially when small boost fields are used.

Adult↗

Executive impairment among the functionally dependent: comparisons between schizophrenic and elderly subjects.

OBJECTIVE: Executive deficits have traditionally been associated with frontal lobe brain damage. They are relevant to a variety of disabling mental conditions, including schizophrenia and Alzheimer's disease. To measure these deficits, the authors developed the Executive Interview, a 25-item, 15-minute interview. It has been validated among elderly subjects across a wide range of functional impairment. METHODS: Forty young, chronically ill schizophrenic residents of a state mental health facility and 104 elderly residents, representing three levels of care, of a comprehensive retirement community were tested with the Executive Interview and the Mini-Mental State. RESULTS: When age, gender, education, and number of prescribed medications were controlled, cognitive impairment on the Executive Interview and Mini-Mental State rose with level of care. The Executive Interview alone discriminated between subjects at each level of care, and it was more sensitive to cognitive impairment than the Mini-Mental State. Executive Interview scores correlated the strongest with level of care. Mini-Mental State scores, number of prescribed medications, and age also correlated significantly. Schizophrenic patients showed as much executive impairment on the Executive Interview as elderly subjects at the same level of care despite significant differences in age, sex, and neuroleptic use. Executive Interview and Mini-Mental State scores were highly correlated among the elderly but less so among the schizophrenic patients. Cross-group differences were also found in the pattern of failure on selected Executive Interview items despite similar total Executive Interview scores. CONCLUSIONS: Increasing executive dyscontrol is associated with the need for increasing levels of care and supervision. This finding is neither age nor disease specific. Cross-group differences on selected Executive Interview items suggest the existence of disease-specific patterns of failure. Their recognition could prove useful in the identification of anatomically or pathophysiologically distinct subgroups among patients with executive dyscontrol.

Activities of Daily Living↗

Neuman's framework and ventilator dependency: a pilot study.

The purpose of this article is to illustrate how the Neuman systems model guided a pilot study with ventilator-dependent patients. Mechanical ventilation was the external stressor to which these subjects reacted. The interaction of Neuman's client system variables was investigated to see which variables most influenced the weaning process. The pilot served to link model concepts with research variables and to identify appropriate procedures and tools for data collection.

Activities of Daily Living↗

An examination of cluster-based classification schemes for DUI offenders.

This study examines the utility of cluster-based classification schemes for DUI offenders. Variables from previous empirical typologies and multiple domains were used in a series of cluster analyses in order to examine replicability across independent samples, across clustering algorithms and across sets of psychometric indicators. The arbitrary nature of cluster solutions and the external validity of cluster-based schemes, with respect to an outcome criterion constructed synthetically from earlier research, was examined. Only three of eight cluster techniques (Ward's, K means, and complete linkage) yielded meaningful results. For these techniques, replicability was poor across samples, algorithms and sets of psychometric indicators. Results indicated that identified clusters were arbitrary. Although external validity analysis yielded positive results, the possibility that external validity was a function of underlying dimensions was discussed, as were other implications of the findings.

Adult↗

Koelliker on Cajal: translated excerpts from Erinnerungen aus meinem Leben.

Albert Koelliker was the foremost histologist of the late 1800s. Koelliker personally worked on many of the same issues as Santiago Ramón y Cajal and was well placed to provide a contemporary commentary on the reception of Cajal's ideas. We have translated selected excerpts from Koelliker's autobiography, Erinnerungen aus meinem Leben, which discuss the ideas of Cajal which were treated no differently than most present day hypotheses; they were disputed on logical, technical, and personal grounds.

Histology↗

Comparison of the in vitro and in vivo cardiovascular effects of two structurally distinct Ca++ channel activators, BAY K 8644 and FPL 64176.

We compared the cardiovascular effects of two structurally distinct L-type Ca++ channel activators, the 1,4-dihydropyridine Bay K 8644 and the benzoylpyrrole FPL 64176. Both compounds prolonged action potential duration and enhanced contractility in guinea pig papillary muscle with these responses being greater in the presence of FPL 64176 compared to (S)-Bay K 8644. (S)-Bay K 8644 (300 nM) and FPL 64176 (300 nM) increased whole-cell Ca++ channel current amplitude in neonatal rat ventricular cells by 249 +/- 14 and 484 +/- 100%, respectively. (S)-Bay K 8644 had little effect on Ca++ channel activation but significantly enhanced the rate of Ca++ channel current inactivation. FPL 64176 significantly slowed Ca++ channel current activation and inactivation. Tail current decay at -50 mV was monoexponential in the presence of (S)-Bay K 8644 and had a time constant of 4.59 +/- 0.16 msec. FPL 64176 produced biexponential tail current decays at -50 mV with fast and slow time constants of 4.30 +/- 0.30 and 44.52 +/- 4.56 msec, respectively. Intravenous administration (1-100 micrograms/kg) of Bay K 8644 and FPL 64176 produced large increases in cardiac contractile force and diastolic blood pressure in anesthetized dogs. Pretreatment with nifedipine attenuated the blood pressure response to FPL 64176 but not the effects on cardiac contractility. This study demonstrates that the benzoylpyrrole FPL 64176 defines a new and potent class of Ca++ channel agonist molecule and that this compound has pharmacological activity that differs, at least in some respects, from the 1,4-dihydropyridine group of agonists.

3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethy↗

Molecular biology of the peptide hormone families.

The application of recombinant molecular biology has lead to remarkable advances in our understanding of the basic mechanisms of cell function in general and of the polarized GI endocrine cell in particular. This article focuses on some of the advances made towards determining the contribution of peptide hormone gene regulation to the regulation of physiological events in the GI tract. Application of these techniques to other subcellular processes involved in peptide hormone physiology such as subcellular trafficing in the regulated secretory pathway and post-translational processing have been equally impressive. For example, many of the key enzymes in the peptide hormone processing cascade have been cloned and are being studied at a molecular level. We have focused this article on the SS and gastrin peptides because of their known physiologic importance and interactions, and the depth of analysis accomplished to date. Studies using SS and gastrin as models have established principals that cover the spectrum of luminal regulation of gene activity to the identification of a single amino acid residue responsible for cAMP induction of SS gene expression. Many genes in the GI endocrine system have been cloned and the article by Dr. Habener (elsewhere in this issue) discusses progress made in understanding the complex regulation of the glucagon gene. We anticipate similar advances in studies of cholecystokinin, secretin, motilin, VIP, pancreatic polypeptide, and neuropeptide Y, whose genes have been cloned and initially characterized. Finally, as outlined in this article, the mechanisms of regulation of a specific gene often differ between sites of expression, even within the GI tract. Direct studies of the subcellular mechanisms regulating gene expression and other processes in GI endocrine cells await novel methods to maintain and propagate these cells. These studies will almost certainly involve new and creative uses of recombinant molecular biology.

Animals↗

Salmonella mutagenicity tests: V. Results from the testing of 311 chemicals.

311 chemicals were tested under code, for mutagenicity, in Salmonella typhimurium; 35 of the chemicals were tested more than once in the same or different laboratories. The tests were conducted using a preincubation protocol in the absence of exogenous metabolic activation, and in the presence of liver S-9 from Aroclor-induced male Sprague-Dawley rats and Syrian hamsters. Some of the volatile chemicals were also tested in desiccators. A total of 120 chemicals were mutagenic or weakly mutagenic, 3 were judged questionable, and 172 were non-mutagenic. The remaining 16 chemicals produced different responses in the two or three laboratories in which they were tested. The results and data from these tests are presented.

Animals↗

An inside-out theory of attention.

The brain has two attentional systems; one attentional system is devoted to intrapersonal space and the second attentional system to extrapersonal space. The development of these two attentional systems with inward or outward focus arose from the hemispheral neural systems designed for attending to extrapersonal contralateral space. As a necessary consequence of the brain changes to develop language, one of the hemispheral attentional systems was altered for intrapersonal attention while the other hemispheral attentional system became obligated to attend to all of extrapersonal space. This conceptualization of attention provides a coherent explanation for the confusing hemispheral dominance proposed for attention on the basis of clinical hemineglect, i.e. that the left hemisphere attends to right extrapersonal space and that the right hemisphere attends to both left and right extrapersonal space. This conceptualization also provides a meaningful account of denial of limbs (anosognosia) and imagery.

Animals↗

Extended field irradiation for carcinoma of the uterine cervix with positive periaortic nodes.

Forty-three patients were treated with extended field irradiation for periaortic metastasis from carcinoma of the uterine cervix (FIGO stages IB-IV). Twelve patients (28%) remained continuously free of disease to the time of analysis or death from intercurrent disease, 20 (46%) had persistent cancer within the pelvis, 11 (26%) had persistent periaortic disease, and 23 (53%) developed distant metastasis. The actuarial 5-year survival rate was 32%. The results correlated well with the periaortic tumor burden at the time of irradiation. None of 19 patients (0%) with microscopic or small (less than 2 cm) periaortic disease had periaortic failures, compared to 29% (4/14) of those with moderate-sized (2-5 cm) disease and 70% (7/10) of those with massive (greater than 5 cm) periaortic metastasis. Similarly, the 5-year survival rates were 50% (6/12) with microscopic disease, 33% (2/6) with small gross disease, 23% (3/13) with moderate-sized disease, and 0% (0/10) with massive periaortic metastases. Only 10% (1/10) of patients whose tumor extended to the L1-2 level survived 5 years, compared with 31% (9/29) of those whose disease extended no higher than the L3-4 level. The periaortic failure rates correlated to some extent with the dose delivered through extended fields, although the difference was not statistically significant. Only 8% (1/13) of those who had undergone extraperitoneal lymphadenectomies developed small bowel complications, compared with 25% (7/29) of those who had had transperitoneal lymphadenectomies. The incidence of small bowel obstruction was 8% (1/13) following periaortic doses of 4000-4500 cGy, 10% (1/10) after 5000 cGy, and 32% (6/19) after approximately 5500 cGy. From this, we concluded that the subset of patients who would benefit most from extended field irradiation are those in whom the residual disease in the periaortic area measures less than 2 cm in size at the time of treatment, whose disease extends no higher than L3, and whose cancer within the pelvis has a reasonable chance of control with standard radiation therapy techniques.

Adult↗

Dorsal penile nerve block in neonatal circumcision: chloroprocaine versus lidocaine.

Dorsal penile nerve blocking (DPNB) has been used with success in decreasing neonatal stress during circumcision. This study was designed to confirm the effectiveness of lidocaine in DPNB and to demonstrate that chloroprocaine, a shorter acting anesthetic, is as effective in blocking circumcision stress as lidocaine, but, because of its shorter plasma elimination half-life and time of onset of action, is safer. Five groups of 15 neonates were matched for weight, age, and Apgar scores and randomly assigned to a control group, one lidocaine group and three chloroprocaine groups with 2-, 3- and 5-minute postinjection waiting periods. Each neonate was subjected to six events during circumcision for which heart rate, tissue oxygenation, and cry duration were recorded. We found that, as in previous investigations, DPNB with lidocaine was effective in reducing neonatal stress, as was evident from decreased excursion from baseline heart rate, tissue oxygenation, and cry duration when compared with the control group (nonblocked). Furthermore, chloroprocaine DPNB approximates the effectiveness of lidocaine, as was evident from decreased change from baseline cry duration, tissue oxygenation, and heart rate during the most stressful events, particularly in the 3-minute wait chloroprocaine group. This more rapid onset of regional anesthesia decreases DPNB circumcision time and benefits patients, parents, and physicians.

Anesthetics, Local↗