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Biomedical subjects

S Ross

Publications and source records attributed to S Ross.

At least 199 records · Page 11Linked to original sources
PubMed1988

Role of a SER immune suppressor in immune surveillance.

A potent immunosuppressor factor, known as SER (suppressive E-receptor factor) has been identified in the body fluids of cancer patients. SER has been proven to be immunochemically analogous to the fetal form of haptoglobin. In this paper, we examine the role of SER immune suppressor in the immune surveillance mechanism of the host, using an affinity-purified SER. As shown in this study, SER, at microgram/ml concentrations, inhibits the T-cell proliferation induced with either monoclonal or polyclonal T-cell activators in vitro in human, and also inhibits the primary antibody response to T-dependent antigens in vivo in mice. Likewise, SER also inhibits the immunoglobulin synthesis of human B lymphocytes induced by a B-cell mitogen, pokeweed mitogen, in the presence of a tumour promoter, phorbol myristate acetate (PMA). In contrast to the T-dependent antibody response in vivo in mice or T-dependent mitogen response in vitro in human, SER does not interfere with the T-independent antibody responses to DNP-Ficoll or TNP-LPS in mice. SER also interferes with the natural killer cell function of human peripheral blood mononuclear cells. Although SER inhibits the phagocytic functions of human peripheral neutrophils, it requires at least 10-20 times the concentration of SER present in normal human plasma. Since this concentration of SER is attainable in the sera of solid tumour-bearing patients, highly elevated levels of SER could predispose the patients to microbial infections as well. This study demonstrates that purified SER manifests multi-faceted down-regulatory effects on the defence mechanism of hosts, thereby it could compromise the patients' cell-mediated immunity in vivo.

Animals↗
PubMed1987

Further analysis of spontaneous membrane potential activity and the hyperpolarizing response to parathyroid hormone in osteoblastlike cells.

Whole cell voltage clamp measurements using the patch technique on well-attached and well-spread cells of an osteoblastlike line (ROS 17/2.8) show the same spontaneous membrane potential activity as measurements with inserted microelectrodes. Furthermore, membrane potential measurements during the first 80 milliseconds (ms) following microelectrode penetration of the cell membrane usually show no decay. There is also good agreement between values of cell membrane resistance obtained by the microelectrode technique, the whole cell patch clamp technique, and the single channel patch clamp technique. These results indicate that our microelectrode measurements are not dominated by leak-induced artifacts, and that the spontaneous membrane potential activity is not induced by Ca2+ leakage around the microelectrode. The spontaneous membrane potential activity is eliminated in the presence of the Ca2+ ionophore A23187, also in serum-free medium, and by K+ and Ca2+ channel blockers, but it is not affected by the hyperpolarizing responses to parathyroid hormone (PTH) and dibutyryl cAMP, which persist under all of these conditions. These results support the hypothesis that the spontaneous membrane potential activity is related to repeated fluctuations of internal [Ca2+] and that such fluctuations result from a feedback loop involving Ca2+ channels or Ca2+ pumps in the cell membrane.

Animals↗
PubMed1987

An inexpensive dual-excitation apparatus for fluorescence microscopy.

Ion sensitive indicator molecules can be employed in conjunction with fluorescence microscopy in single cells to measure rapid changes in the intracellular concentration of several ionic species. A number of these probes (e.g. fura-2) require the capability of measuring emission intensity at two excitation wavelengths to quantitate properly intracellular ion concentration. We have developed a simple dual-excitation apparatus for use in such applications. The apparatus switches the excitation filter within 150 ms. This economical apparatus is well suited in situations where the ionic concentration of interest is changing relatively slowly. Moreover, by synchronizing the device's action with an external stimulus, rapid and reproducible ionic changes in excitable tissue also can be measured.

Animals↗
PubMed1986

Tolerance and pilot pharmacokinetics of amiflamine after increasing single oral doses in healthy subjects.

Oral doses of 1 to 100 mg amiflamine, a new reversible monoamine oxidase type A-selective inhibitor, were given for the first time in humans to six healthy men. No apparent pharmacologic effects were recorded until the 80 mg dose. After 100 mg, one subject developed symptoms indicative of an overdose. Amiflamine is extensively metabolized by two consecutive N-demethylations. The biotransformation patterns in plasma and urine were found to correlate with the debrisoquin metabolic ratio.

Adult↗
PubMed1986

Membrane Electrical Noise in Chara corallina: II. Effects of Inhibitors on the Low Frequency Spectral Component.

Certain inhibitors have been found to affect the low frequency spectral component of the electrical noise power spectrum in Chara corallina. Application of the ATPase inhibitor N,N'-dicyclohexylcarbodiimide removed the low frequency spectral component, strengthening the case that the component is produced by active proton pumping. Cytocholasin B, which inhibits cyclosis in internodes of C. corallina, removed the low frequency spectral component in a time-dependent fashion which was correlated with the cessation of streaming. The protonophore carbonyl cyanide m-chlorophenylhydrazone did not produce consistent effects on the low frequency spectral component in these cells.

Journal Article↗
PubMed1986

Constant inclined pelvic traction for treatment of low back pain.

The authors describe a technique of continuous pelvic traction applied to a select group of 46 patients with low back pain, who had not responded to at least two weeks of treatment by bed rest and analgesic medication before hospitalization. The traction technique included the use of force equivalent to 25% of body weight, directed at an angle of (15) to the plane of the bed. A mechanical analysis of the technique is described and the results of treatment and the efficacy of the technique discussed.

Back Pain↗
PubMed1986

A submucosal antral mass caused by cytomegalovirus infection in a patient with acquired immunodeficiency syndrome.

A 29-yr-old homosexual man with acquired immunodeficiency syndrome presented with watery diarrhea and fever. Upper gastrointestinal endoscopy was performed to obtain duodenal aspirates and biopsies. A 4-cm submucosal mass in the gastric antrum was identified. Subsequent abdominal CT scan confirmed the presence of this antral mass. An attempt at CT guided needle biopsy was nondiagnostic. Because the mass possibly represented a Kaposi's sarcoma or lymphoma, exploratory laparotomy and open biopsy was performed. Examination of the biopsy specimen showed inflammatory debris with multiple intranuclear cytomegalovirus inclusions. This report describes a case of a submucosal antral mass caused by localized cytomegalovirus infection in a patient with acquired immunodeficiency syndrome.

Acquired Immunodeficiency Syndrome↗
PubMed1985

Membrane Electrical Noise in Chara corallina: I. A Low Frequency Spectral Component.

Some aspects of the membrane physiology of the giant-celled alga Chara corallina have been studied using the techniques of membrane noise analysis. Cellular voltage noise was measured by means of a microelectrode inserted in the vacuole of the cell. The significant feature of spectra estimated from voltage noise signals in these cells was a low-frequency component possibly associated with the active, electrogenic proton pumping which occurs in these cells. The effect of high external pH is described.

Journal Article↗
PubMed1985

Computerized tomography as a guide in the diagnosis of temporomandibular joint disease.

As described, CT is a noninvasive method for providing detailed views of both the soft and hard tissues of the TMJ region. Because internal derangements of the joint involve both of these structures, CT can provide an invaluable tool in the study, diagnosis, and treatment of various disorders of this nature. It is extremely important, however, to create a close working relationship with the radiologist who will be performing these studies. Only with adequate clinical study and information communicated to the radiologist can true benefits be obtained. As CT scans are available nationwide, this technique should be available to nearly any practitioner in the country. CT can be useful in both diagnostic and therapeutic modalities. On a diagnostic basis, it can provide a tomographic study of the osseous structures of the condyle, fossa, articular eminence, and surrounding hard tissues. By varying the slices, views of the medial and lateral poles as well as the central portions of the region, can be obtained. In this way, various arthroses, tumors, cysts, fractures, true ankylosis, neoplasias, developmental abnormalities, and other bony abnormalities can be clearly found. Therapeutically, CT can evaluate the success of treatment aimed at reestablishing proper disk-condylar relationships. However, the major advantage of TMJ CT is the observation of the soft tissue of the articular disk. By the use of CT, especially enhanced by the blink mode, we can see how the disk relates to the condyle. If a series of views are taken in both the closed and open position, we can observe the disk-condylar relationship during this range of motion.(ABSTRACT TRUNCATED AT 250 WORDS)

Diagnosis, Differential↗
PubMed1985

[Embolization therapy of kidney tumors--experience with a group of 60 patients].

A series of 60 patients is reported, in whom embolization was carried out because of a kidney tumor. In 9 cases, this treatment was given for purely palliative reasons, but in the remaining 51 cases, this treatment was a preoperative measure in order to achieve coagulation or "dry the tumor out" intra vitam. Although we formerly used materials such as gel foam and muscle homogenates, in the last three years, Ethibloc or pure alcohol has been used exclusively. The risks involved in this therapy are discussed. In patients with large arteriovenous shunts or fistulas, alcohol should not be used and we prefer polyacrylic agents like Ethibloc.

Carcinoma, Renal Cell↗
PubMed1984

Bull's-eye lesions: a new gastrointestinal presentation of mastocytosis.

Systemic mastocytosis is a rare disorder that infrequently affects the GI tract. Bowel involvement in mastocytosis is characterized by thickened folds and small mucosal nodules, and there is an increased incidence of peptic ulcer disease and malabsorption. This paper describes a new case of mastocytosis that presented radiographically as 1.0-1.5 cm gastric and duodenal nodules. Some of the duodenal nodules were bull's-eye lesions with central collections of barium. Mastocytosis, along with primary neoplasms, aberrant pancreas, eosinophilic granuloma, and metastases should be included in the differential for bull's-eye lesions of the GI tract.

Adult↗