PubMed Health⌕ Search

Biomedical subjects

B S Joseph

Publications and source records attributed to B S Joseph.

At least 19 recordsLinked to original sources
PubMed1994

Estimation of metabolic rate using qualitative job descriptors.

This project developed two methods to estimate metabolic rate that can be used easily and provide acceptable precision. The methods were developed from the measurement of oxygen consumption on 80 typical jobs in automotive manufacturing. The Ready-Reference Method uses three easily identified, dichotomous characteristics to classify the job into one of four levels of metabolic rate. The characteristics are based on motion of the hands, weights or forces, and walking; standard error of estimate was 68 kcal/hour. The Component Method has four terms that account for hand motion, walking/carrying, lifting, and pushing/pulling. Hand motions and lifting factors are characterized by three or four categories with a reference value to make the determination easier by using more qualitative data. Walking/carrying and pushing/pulling data are noted as typical distances traveled in one minute. The standard error of estimate for this method was 62 kcal/hour. In addition to a smaller standard error of estimate, the further advantage of the Component Method over the Ready-Reference Method is an ability to point toward the largest contributors to metabolic rate.

Automobiles↗
PubMed1989

Electrophysiologic responses of human sural nerve to temperature.

The purpose of this study was to assess the conduction, specifically the latency and amplitude of the sensory nerve action potential (SNAP), of the sural nerve as a function of intraneural temperature of the leg. The electrophysiologic responses of the sural nerve were determined at different temperatures in 22 healthy adults. Distal sensory latency and amplitude of the sural SNAP was determined at 1 degree C intervals over a limb temperature range of 23 degrees to 40 degrees C. Limb temperature was monitored with a thermistor probe placed subcutaneously near the sural nerve. Ice bath soaks were used for cooling and infrared radiation for warming the limbs. An analysis of covariance was performed for the SNAP latencies and amplitudes to determine the effect of gender and leg (right or left) at each temperature level. No effect of gender or leg on neural conduction was detected in individual subjects. A regression analysis was then used on pooled data to determine the effect of temperature on sural SNAP latency and amplitude. An inverse linear change in the latency of sural SNAP was observed over the temperature ranges used. Mean latency increased 0.1 msec per 1 degree C increase in subcutaneous temperature. A direct relationship between amplitude of the SNAP and temperature was determined. Mean amplitude increased 0.3 muV per 1 degree C increase in subcutaneous temperature. The results of this study support previous reports, which state that SNAP latency is indirectly related to the intraneural temperature. Clinical electromyographers must monitor the temperature of the lower leg and foot whenever sensorineural conduction of the lower limbs is performed.

Action Potentials↗
PubMed1982

Investigation of cumulative trauma disorders in a poultry processing plant.

Cumulative trauma disorders such as carpal tunnel syndrome and tenosynovitis can be caused, precipitated, or aggravated by repeated exertions with the hand. This paper describes a study in a poultry processing factory that proceeds from an analysis of health records to an analysis of work methods, postures and forces. Alternative work procedures and knife designs are recommended to reduce stressful work postures and forces.

Animals↗
PubMed1981

Multiple sclerosis serum and cerebrospinal fluid immunoglobulin binding to Fc receptors of oligodendrocytes.

Suspensions of bovine oligodendrocytes were used to study the immunofluorescent staining properties of sera from multiple sclerosis (MS) patients and normal individuals. All sera (14 MS patients, 8 patients with other neurological diseases, and 11 normal individuals) showed positive oligodendrocyte staining by indirect immunofluorescence. Staining persisted after extensive absorption of sera with bovine liver to remove nonspecific binding. Similar findings were obtained for cerebrospinal fluid from all 5 MS patients as well as all 5 patients with other neurological diseases. In additional studies to determine if binding is mediated by the Fc fragment of IgG, results were: (1) ultracentrifuged normal and MS sera failed to react with oligodendrocytes, (2) positive staining with oligodendrocytes was observed after heat aggregation of IgG, (3) ox red blood cells, complexed with antibody, reacted with oligodendrocytes to produce strong rosette formation, and (4) the rosette formation could be blocked by prior treatment of oligodendrocytes with heat-aggregated IgG. The studies fail to support a previous claim for specific binding of immunoglobulins to oligodendrocytes in MS. However, they confirm and extend previous findings that the binding of IgG to oligodendrocytes may not necessarily be an antigen-antibody reaction. Therefore, adherence reactions with a putative antibody must exclude Fc-mediated binding.

Animals↗
PubMed1976

Mechanism of injury of virus-infected cells by antiviral antibody and complement: participation of IgG, F(ab')2, and the alternative complement pathway.

Antibody-mediated C-dependent lysis of cell lines infected with herpes simplex type 1 virus, influenza A degrees virus, measles virus, and mumps virus occurred by the alternative C pathway with the participation of IgG antibodies. Lysis occurred only with immune human sera, Mg++ EGTA immune sera, and immune sera depleted of C4 or treated with Fab anti-C4. Lysis did not occur with nonimmune sera, Mg++ EDTA immune sera, and immune sera heated 50 degrees C for 25 min, depleted of factor B or treated with Fab antifactor B. Lysis was restored to heated and factor B immunodepleted immune sera by addition of factor B, but not by addition of an excess of C2. Further studies showed that lysis of HeLa cells infected with measles virus was induced by both immune IgG and F(ab')2 but not Fab' in the presence of a nonantibody-containing human C source. Lysis of measles virus-infected cells was also indpendent of movement of viral antigens on the surface of the infected cells, as inhibition of viral antigen capping by cytochalasin B or sodium azide was not associated with abrogation of immune lysis.

Antibodies, Viral↗
PubMed1976

Measurement of virus antigens on the surface of HeLa cells persistently infected with wild type and vaccine strains of measles virus by radioimmune assay.

Persistent states of measles virus infection have been established in HeLa cells by using Edmonston strain virus and two types of measles virus vaccine (M-VAC and Schwarz). The absolute amount of surface viral antigens expressed on these cells infected separately with the three viruses has been assessed by a newly developed method which employs [125I]-labelled Fab fragments of immunoglobulin G (IgG) from immune human sera. This method was used to determine the level of viral antigenic expression on acutely infected HeLa cells harvested at a time when 95 to 100% of cells could be lysed by antiviral antibody and complement. From our data, more than 1 X 10(6) antibody molecules must bind to each cell infected with measles virus before complement dependent lysis can occur in a homologous test system. Persistently infected cells bind 2 to 3 times less antibody than acutely infected cells and correspondingly exhibit less susceptibility to humorally-mediated immune lysis.

Antigens, Viral↗
PubMed1975

Immunologic injury in measles virus infection. II. Suppression of immune injury through antigenic modulation.

Upon the addition of antibody to measles virus, measles virus antigens expressed on the surface of infected cells can be modulated from the cell's membrane in vitro. Removal of measles virus antigens from the surface of cells occurs relatively rapidly and is accompanied by a parallel reduction in the ability of antibody and complement to lyse these cells. Modulation of surface viral antigens can occur in the absence of cap formation and is fully reversible once measles virus antibodies are removed from culture medium. Protracted exposure of acutely infected cells to measles virus antibodies results in a population of cells that exhibit normal cytomorphology and growth behavior. These cells continue to express measles virus antigens internally, but not at the cell surface, and are refractory to immune lysis. Once antiviral antibody is removed, measles virus antigens again appear on the cell surface, giant cell and syncytial formation occur, and cell death follows. These observations may explain the persistence of virus in spite of a vigorous host antiviral immune response in certain chronic infections of man.

Antibodies, Viral↗
PubMed1975

Immunologic injury of cultured cells infected with measles virus. I. role of IfG antibody and the alternative complement pathway.

In these studies, a number of human cell lines including epithelial, neural, glial, and lymphoid cells infected with several strains of measles virus were found to be lysed upon incubation with fresh sera from humans containing antibody measles virus. In all instances, the cytolytic event was mediated by alternative complement (C) pathway without a significant contribution from classical pathway. In contrast, isolated measles virus in conjunction with antibody was found to selectively activate the classical C pathway. Measles antibodies of the IgG class, but not the IgA class, possessed cytolytic potential against cells infected with measles virus. Human IgG antibodies could directly activate the alternative C pathway. No defect was found in cytolytic measles antibody in sera or cerebrospinal fluid from patients with subacute sclerosing panencephalitis, nor was the alternative C pathway impaired in sera from these patients. Sera from newborn humans exhibited a functional alternative C pathway.

Absorption↗
PubMed1975

Antibody-induced capping of measles virus antigens on plasma membrane studied by electron microscopy.

Antibodies specific for measles virus could redistribute ("cap") virus antigens on infected HeLa cells as shown by transmission and scanning electron microscopy. Using an indirect immunoperoxidase technique, infected cells showed diffuse, circumferential distribution of virus antigens over the cell surface when mixed with antibody at 4 C. At 37 C, virus-coated microvilli concentrated on one pole of the cell, leaving the remainder of the plasma membrane devoid of both viral antigens and microvillus projections. Whereas extreme polar displacement of virus-antibody complexes frequently occurred, endocytosis was rarely seen. The findings indicate that antiviral antibodies can move and cluster virus on plasma membranes and suggest that virus-antibody complexes are stripped and shed from the cell surface.

Antibodies, Viral↗
PubMed1975

Replication and persistence of measles virus in defined subpopulations of human leukocytes.

Replication of Edmonston strain measles virus was studied in several human lymphoblast lines, as well as in defined subpopulations of circulating human leukocytes. It was found that measles virus can productively infect T cells, B cells, and monocytes from human blood. These conclusions were derived from infectious center studies on segregated cell populations, as well as from ultrastructural analyses on cells labeled with specific markers. In contrast, mature polymorphonuclear cells failed to synthesize measles virus nucleocapsids even after infection at a relatively high multiplicity of infection. Measles virus replicated more efficiently in lymphocytes stimulated with mitogens than in unstimulated cells. However, both phytohemagglutinin and pokeweed mitogen had a negligible stimulatory effect on viral synthesis in purified populations of monocytes. In all instances the efficiency of measles virus replication by monocytes was appreciably less than that of mitogenically stimulated lymphocytes or of continuously culture lymphoblasts. Under standard conditions of infection, all of the surveyed lymphoblast lines produced equivalent amounts of measles virus regardless of the major histocompatibility (HL-A) haplotype. Hence, no evidence was found that the HL-A3,7 haplotype conferred either an advantage or disadvantage with respect to measles virus synthesis in an immunologically neutral environment. A persistent infection with measles virus could be established in both T and B lymphoblasts. The release of infectious virus from such persistently infected cells was stable over a period of several weeks and was approximately 100-fold less than peak viral titers obtained in each respective line after acute infection.

B-Lymphocytes↗