Method for the isolation of Escherichia coli relaxed mutants, utilizing near-ultraviolet irradiation

Near-ultraviolet radiation (300 to 380 nm) induces a transient growth inhibition in "stringent" (rel+) strains of Escherichia coli, whereas "relaxed" (rel-) strains are only mildly affected. This difference permits rapid isolation of large numbers of relaxed mutants of E. coli.     

Regulatory variants for the expression of H-2 antigens. I. Isolation and characterization

By subjecting "mutagenized" mouse myeloma cells repeatedly to selection with antiserum against H-2Kd, we isolated variants that expressed little or no H-2Kd alloantigens. The phenotype was unstable, with the culture accumulating revertants in the absence of selective pressure. The variants not only failed to express the selected antigen, but also the antigen coded by the closely liked H-2Dd gene. The cells reexpressed this antigen with the same kinetics as for the selected antigen. Several physiologic parameters (karyotype, cell morphology, size, and growth curves) were not altered by the loss of H-2 antigens.However,when injected iv, the H-2-deficient cells did not lodge in the spleen as readily as did the wild-type cells.     

The roles of muscarinic receptor subtypes in modulation of nasal ciliary action

OBJECTIVE: Clinicopathological features of mycobacteriosis were studied by means of microscopical examination of 34 autopsy cases in patients with acquired immunodeficiency syndrome (AIDS) and the diagnostic methods were evaluated. METHODS: All cases were anatomized, sampled, fixed and embedded routinely and stained with hematoxylin-eosin. Acid fast stain was applied to identify the mycobacteria. The pathological sections and files were reviewed systemically and retrospectively. RESULTS: Thirty-four cases of mycobacteriosis, including Mycobacterium avium-intracellular complex (MAI) infection (20 cases) and Mycobacterium tuberculosis (10 cases) and mixed infection of both pathogens (4 cases) were found out of 151 autopsy AIDS patients. MAI infection involved mostly the lymph nodes (21 cases) and followed by spleen, liver and lung, etc. The infection were often disseminated and characterized by proliferation of histocytes with foamy or vacuolar cytoplasm containing acid fast bacilli and formation of granulomatous nodules. Tuberculosis often involved the lung (10 cases) and lymph node (8 cases), the typical manifestations of which were caseous necrosis and tuberculation. Other opportunistic infections and neoplasmas occurred with mycobacteriosis in 25 cases. CONCLUSIONS: Mycobacteriosis, especially the tuberculosis and MAI infection are common in patients with AIDS, which are often disseminated and involved the lung and lymph node. The diagnosis can be made according to the specific pathological appearances and positive acid fast stain.     

Various aspects of price formation in public health

The main problems involved in estimating the cost of medical service are discussed. Up to the present time, there was no universal approaches to price formation in practical public health. Economists and public health organizers are not trained to cope with this task. Based on the results of five-year studies and published data, the author present in detail the methodology of practical price formation and offer the typical problems in price estimation. The recommendations contained in this paper will help improve the work of specialists in price formation and aid all those engaged in the sphere of paid medical service.     

The localization and functional significance of arylsulfatases in parasitic sarcosporidian protozoa in the tissue-cyst life cycle phase

Ten patients with perennial allergic rhinitis and 10 healthy subjects were studied to determine most discriminative nasal irrigation fluid marker(s) and to compare samples that were collected at baseline and over a 1-hour period, every 15 minutes. The latter were pooled and designated 1-hour sample. In the nasal irrigation we investigated the following inflammatory cells and soluble mediators: eosinophils, neutrophils, granulocyte-macrophage colony-stimulating factor, interleukin-4, interleukin-6, interleukin-8, ECP, EPX, MPO, leukotriene C4, leukotriene B4, prostaglandin E2, tryptase and fibrinogen. Patients with PAR were then treated for 2 weeks with the topical nasal steroid. The only marker that discriminated patients with perennial allergic rhinitis and healthy subjects was eosinophil count (EO%): correspondingly 14.01 +/- 5.8 and 0.18 +/- 0.09, (M +/- SD). Difference between the studied groups did not depend on the time of irrigation, baseline or 1-hour. EO% was also the only marker of a clinically successful treatment with the nasal steroid, 14.01 +/- 5.8 and 0.87 +/- 0.4, before and after treatment respectively. We conclude that EO% is the most sensitive inflammatory marker of perennial allergic rhinitis, and that baseline nasal irrigation can be used to study nasal mucosal inflammation.     

Sequence analysis of DNA randomly amplified from the Saccharomyces cerevisiae genome

OBJECTIVES: To report the features of malignancies responsible for a chest wall mass and involving the sternum, the sternocostal and/or sternoclavicular joints, the chondrocostal junction and/or the adjacent soft tissues. METHODS: The medical records of patients with a chest wall mass due to malignant disease were reviewed retrospectively. The following data were abstracted from each record: characteristics of the pain and mass, constitutional symptoms, physical findings, laboratory test results, findings from imaging studies (plain radiographs, computed tomography and magnetic resonance imaging of the chest, radionuclide bone scan), histologic features of the biopsy specimen from the chest wall mass and origin of the mass. RESULTS: Seven men and three women with a mean age of 53.1 years were included in the study. A single patient had a history of malignant disease (lymphoma); in the remaining nine patients the chest wall mass was the first manifestation of the malignancy. All ten patients had pain with a mixed time pattern. The mass was located on the sternum in half the patients and in a parasternal location in the other half. Erythrocyte sedimentation rate elevation was found in seven patients, an increased serum level of lactate dehydrogenase in one and a monoclonal immunoglobulin in three. Sternal lesions were visible on plain radiographs in four patients. Computed tomography of the chest consistently disclosed sternal or sternocostal lytic lesions with spread to the adjacent soft tissues; in five cases, enlarged lymph nodes were visible in the anterior part of the mediastinum. Magnetic resonance imaging of the chest did not add to the information provided by computed tomography. Radionuclide uptake on the bone scan was increased, decreased, or normal at the site of the lesion. The cause was Hodgkin's disease in two cases, non-Hodgkin's lymphoma in three, metastatic bone disease in two (from an adenocarcinoma of the lung and a hepatocarcinoma, respectively), multiple myeloma in one, and solitary plasmacytoma in two. CONCLUSION: A chest wall mass can be caused by a known or as yet undiagnosed malignancy. Chest wall involvement due to malignant disease in rare, however. The specific features of sternal metastases, lymphomas involving the sternum, and sternal plasmacytomas are discussed. Nonmalignant chest wall lesions that can manifest as a bulging or swelling of the chest wall are reviewed.