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Biomedical subjects

J Baker

Publications and source records attributed to J Baker.

At least 343 records · Page 19Linked to original sources
PubMed1967

Mouse-protective properties of Bordetella pertussis serotypes in passive tests.

In a passive protection procedure in which the ed(50) values of Bordetella pertussis antisera were determined, groups of mice were given graded intraperitoneal doses of serum, followed the next day by intracerebral challenge with 100,000 organisms. Antiserum produced with B. pertussis culture 5373, serotype 1.3, protected mice against challenge with culture 18-323, serotype 1.2.3, as effectively as did an antiserum produced with a serotype 1.2.3 culture. When two groups of mice similarly treated with pertussis immune serum were challenged with culture 353Z (serotype 1) and 18-323, respectively, much lower ed(50) values were obtained with the animals challenged with 353Z. Passive protection tests with adsorbed antiserum gave equivocal results, suggesting that some of the adsorbing antigen remained in the serum and interfered with the tests. There was no evidence that serotype is related to protection.

Animals↗
PubMed1966

Bordetella pertussis culture having only species factor 1.

Eldering, Grace (Michigan Department of Public Health, Grand Rapids), Jack Holwerda, and Julia Baker. Bordetella pertussis culture having only species factor 1. J. Bacteriol. 91:1759-1762. 1966.-Preston's description of Bordetella pertussis 353-Z as a culture possessing only factor 1 was confirmed by agglutination and agglutinin-adsorption tests. The ld(50) values of this culture for mice inoculated by the intracerebral route were approximately the same as that of B. pertussis 18-323, the challenge culture in mouse potency tests of pertussis vaccine. In mouse protection tests, vaccine prepared with the factor 1 culture protected as well against challenge with B. pertussis 18-323, which has a broad antigenic pattern, as did vaccines made with cultures possessing factors 2, 3, 4, and 5 in addition to factor 1. When two groups of similarly immunized mice were challenged with 353-Z and 18-323, respectively, much lower ed(50) values were obtained with the animals challenged with 353-Z. This was true whether a factor 1 vaccine or a vaccine with factors 1, 2, 3, 4, and 5 was tested.

Agglutination↗
PubMedDate not supplied

Ectopic secretion of ACTH and met-enkephalin from a thymic carcinoid.

A 51-year old man presented with the classical features of Cushing's syndrome which had evolved over the previous 5 yr, and was found to have ACTH secretion from an atypical thymic carcinoid tumor. Tumor extract, assayed under conditions designed to prevent artefactual generation of peptides, was found to contain a wide variety of immunoreactive hormones including ACTH, alpha-MSH, CLIP, beta-endorphin and met-enkephalin. The ACTH-related peptides were probably derived from a common precursor, pro-opiocortin, but the presence of met-enkephalin suggests the production of a separate type of precursor molecule. The tumor was locally invasive and, depsite subtotal excision and radiotherapy, continued to secrete large amounts of ACTH. Hypercortisolism was controlled longterm with pharmacological adrenal blockade and steroid replacement.

Adrenocorticotropic Hormone↗
PubMedDate not supplied

Chlorpromazine and QX222 block 5-HT3 receptors in N1E-115 neuroblastoma cells.

The effects of chlorpromazine and the lidocaine derivative QX222, which block nicotinic acetylcholine receptors, were examined on 5-HT3 receptors in N1E-115 mouse neuroblastoma cells, using whole cell voltage-clamp and radioligand binding. Electrophysiological studies examining the effects of chlorpromazine and QX222 on 5-HT3 agonist-induced responses revealed IC50s of 0.2 and 8.5 microM respectively. The action was not voltage- or use-dependent and there was no blocking action when chlorpromazine was applied from inside the cell. Chlorpromazine and QX222 inhibited the binding of a radiolabelled 5-HT3 receptor antagonist, [3H]GR65630, with IC50s of 0.9 and 29 microM respectively. Scatchard plots revealed a decrease in affinity (Kd) in the presence of chlorpromazine, but no change in the maximum number of binding sites (Bmax). The results suggest differential actions of the compounds at 5-HT3 and acetylcholine receptors.

Affinity Labels↗
PubMedDate not supplied

Radioligand binding and photoaffinity labelling studies show a direct interaction of phenothiazines at 5-HT3 receptors.

The effects of a range of phenothiazines were examined on 5-hydroxytryptamine3 (5-HT3) receptors in membranes from NIE-115 neuroblastoma cells using radioligand binding. Chlorpromazine, fluphenazine, perphenazine, trifluoperazine and prochlorperazine inhibited specific binding of both the 5-HT3 receptor antagonist [3H]GR65630 and agonist [3H]meta-chlorophenylbiguanide (mCPBG), with Ki values ranging from 0.4 to 3.9 microM. The mode of action of chlorpromazine was further examined using photoaffinity labelling in the presence and absence of 5-HT. Saturation radioligand binding data with both [3H]GR65630 and [3H]mCPBG showed that photoaffinity labelling with chlorpromazine (1 microM) caused a decrease in the maximum number of binding sites observed (35% and 28% for agonist and antagonist, respectively). This decrease was not observed when the membranes were incubated in the presence of 5-HT. The results demonstrate a direct interaction of a range of phenothiazines at the 5-HT3 receptor binding site.

Affinity Labels↗
PubMedDate not supplied

Application of single-donor fibrin glue to burns.

Early tangential excision and immediate grafting of the burn-injured patient has been shown to be effective. Along with the use of this technique, however, comes the potential for significant blood loss, prolonged operative time, and partial loss of graft due to underlying hematoma formation. Based on experience using a pooled fibrinogen preparation, European and Japanese surgeons have provided evidence for the positive hemostatic and skin transplant fixation effects of fibrin glue. This commercial preparation, however, has not been approved by the U.S. Food and Drug Administration for use in the United States because of high risk of hepatitis and HIV transmission. Using a method of preparing highly concentrated fibrinogen utilizing standard blood bank techniques developed at the University of Virginia, we have applied single-donor fibrin glue as an adjunct in the early excision and grafting of 26 patients. Since we have been using fibrin glue, we have noted a marked reduction in operative blood loss and time involved in obtaining hemostasis. Additionally, we have found the application of the grafts to be facilitated by the "stickiness" of the recipient bed. In follow-up, grafts applied utilizing the fibrin glue technique have proceeded to uncomplicated wound healing with an overall 98% graft take.

Adult↗
PubMedDate not supplied

Depressive symptomatology in a general hospital sample of outpatients with temporal lobe epilepsy: a controlled study.

We compared temporal lobe epilepsy (TLE) outpatients attending a general hospital with depressed psychiatric patients and normal control subjects to investigate depressive symptomatology. Both clinician-rated measures and self-report questionnaires were used. Rates of depressive and anxious symptomatology in TLE subjects were higher than those in a normal control sample, but TLE subjects did not differ significantly from controls on anxiety measures. The depressed psychiatric group scored higher than the TLE and control groups on both depression and anxiety measures. Rates of depressive symptomatology in the TLE group were lower than those reported in previous studies for persons attending specialist epilepsy clinics, but similar to the findings of one community study.

Adult↗
PubMedDate not supplied

Granulocyte colony-stimulating factor use in cancer patients.

OBJECTIVE: To conduct a retrospective drug utilization evaluation comparing the use of granulocyte colony-stimulating factor (G-CSF) at a university medical center with the American Society of Clinical Oncology (ASCO) CSFs Practice Guidelines. METHODS: Patients who received G-CSF from June 1, 1996, to December 31, 1996, were identified through the pharmacy computer system and the medical records were reviewed for a randomly selected sample of 26% of the 289 patients identified. Outpatient, inpatient, and electronic medical records were reviewed for the indication, dosage, day of initiation, day of discontinuation, and absolute neutrophil count (ANC) monitoring plan for each course of G-CSF; these records were subsequently compared with the ASCO guidelines. RESULTS: The use of G-CSF after chemotherapy was evaluated in 51 patients who received a total of 182 courses of G-CSF. The goal of chemotherapy was curative in 61% of courses. Sixty-five percent of G-CSF courses were prescribed for primary prophylaxis. Of these, 74% followed chemotherapy in patients with an expected incidence of febrile neutropenia > or =40% or followed chemotherapy in patients with compromised marrow reserve secondary to extensive prior therapy or in patients older than 60 years. Most of the G-CSF courses (75%) were rounded to the nearest vial size. The areas of greatest departure from the ASCO guidelines included aspects of initiation and discontinuation of G-CSF courses and inadequate documentation of ANC recovery. CONCLUSIONS: These results demonstrate a number of specific opportunities for oncology pharmacists to improve the use of G-CSF in patients receiving chemotherapy. Recommendations were made to the pharmacy and therapeutics committee and medical oncologists to improve compliance with the ASCO guidelines.

Aged↗
PubMedDate not supplied

Dog heartworm causing necrotizing granuloma of the lung.

Pulmonary dirofilariasis was diagnosed in a 70-year-old woman by tissue examination after she underwent a right thoracotomy. The preliminary clinical diagnosis was pulmonary coin lesion of probable neoplastic nature. Pulmonary dirofilariasis, caused by the dog heartworm, is occurring with increased frequency in the United States and must be considered in the differential diagnosis of pulmonary coin lesions. We describe the clinicopathological features of this case with special emphasis on the gross examination of the specimen.

Aged↗