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PubMed1978

Eosinophilic gastroenteritis with obstruction. Immunological studies of seven patients.

We studied 7 patients with eosinophilic gastroenteritis presenting with obstruction of the gastrointestinal tract. Five had required surgical treatment for relief of obstructive symptoms or because of diagnostic uncertainty. Immunological studies, including serum immunoglobulins, serum complement, lymphocyte quantitation, and lymphocyte response to nonspecific mitogens revealed no striking abnormalities. None was clinically allergic or food sensitive, and serum IgE was normal in all. A review of the literature since 1970 suggests that the obstructive form of eosinophilic gastroenteritis accounts for about half of the reported cases. Allergy, especially hypersensitivity to food, is not required for the diagnosis.

Adolescent↗
PubMed1975

Immunofluorescence and anti-complement immunofluorescence absorption tests for quantitation of Epstein-Barr virus-associated antigens.

Immunofluorescence absorption methods are described which permit quantitative estimation and differentiation of Epstein-Barr virus (EBV)-associated antigens (virus capsid antigen, VCA, early antigen, EA and EBV-determined nuclear antigen, EBNA) in cell extracts. EBNA was present in all cell lines (producer and non-producer) which carried the EBV-genome, while VCA and EA were present in producer lines only. All the antigens were absent from a lymphoid cell line (MOLT-4) which lacked the EBV-genome, as well as from leukemia cells from peripheral blood. The techniques demonstrated antigenic identity of the various antigens when prepared from different cell lines.

Absorption↗
PubMed1995

The vif gene is essential for efficient replication of caprine arthritis encephalitis virus in goat synovial membrane cells and affects the late steps of the virus replication cycle.

Complex retrovirus genomes contain a variable number of accessory genes, among which is the vif gene. We investigated in vitro the role of the vif gene of caprine arthritis encephalitis virus (CAEV) by studying the phenotype of five vif mutants after infection of primary goat synovial membrane (GSM) cells and blood-derived monocytes/macrophages. Any deletion introduced into the vif gene resulted in slow and low viral replication and production of virions with an infectious titer lower than that of wild-type viral particles. The wild-type phenotype could be restored by the trans expression of the vif gene in a complementation assay. Quantitative PCR and reverse transcription-PCR analyses were performed in order to determine which stage of the replicative cycle was impaired by the vif deletion. Our results demonstrated that CAEV Vif did not act at the level of reverse transcription or transcription but rather at the late stage of virus formation and/or release, as lower amounts of virus were produced after a single replicative cycle. The vif-deleted CAEV produced after 24 h of infection was still able to infect GSM cells, indicating that the vif gene is not essential for virus infectivity but is required for efficient virus production.

Amino Acid Sequence↗
PubMed1979

Complement proteins and macrophages. 1. Quantitative estimation of factor B produced by mouse peritoneal macrophages.

Cobra venom factor was used for the detection of factor B synthesized by mouse peritoneal macrophages. This method was shown to be specific for factor B assay by neutralization by antimouse factor B antibody. The amount of factor B in the culture supernatant, assessed by this method, was found to be dependent on the medium used for cultivation of macrophages. The addition of 25% L cell-conditioned medium to minimal essential medium (LCM-MEM) enhanced the production of factor B and also of lysozyme. Kinetic analysis in LCM-MEM showed that factor B produced by 6 x 10(4) cells/cm2 increased up to 72 hr and reached a plateau at 96 hr. The amounts of factor B and lysozyme produced in LCM-MEM depended upon the number of macrophages. Production of factor B was completely inhibited by 1 microgram of cycloheximide per ml and was restored by its removal.

Animals↗
PubMed1988

A Golgi analysis of the gustatory zone of the nucleus of the solitary tract in the adult hamster.

The somal shapes, dendritic features, and orientations of the neurons within the gustatory zone of the nucleus of the solitary tract were studied with the rapid Golgi method in the adult hamster. These Golgi studies complement previous quantitative morphometric analyses of the distributions of large and small neurons within the gustatory zone. Class 1 neurons are usually fusiform and possess long, relatively unbranched dendrites that often extend beyond the cytoarchitectonic boundaries of the gustatory zone. Class II neurons are multipolar and possess more dendrites that are significantly shorter than those of class I neurons. Both classes of neurons are spine poor. Computer-generated three-dimensional rotational analyses demonstrate that the dendritic arborizations of neurons of the gustatory zone are oriented preferentially in the horizontal plane. Dendrites extend in parallel or perpendicular to the solitary tract, the source of peripheral gustatory inputs, and appear to be positioned spatially to maximize synaptic interactions with these peripheral fibers. These Golgi studies also suggest that individual gustatory neurons may be influenced by incoming gustatory fibers that innervate separate populations of taste buds, a finding that is not predictable from the topographical organization of the gustatory zone.

Animals↗
PubMed2026

Development and Validation of a Predictive Model for Identification of Cognitive Impairment Risk in Older Adults with Subjective Cognitive Decline：A Longitudinal Study.

BACKGROUND: Subjective cognitive decline (SCD) is a transitional state between objective cognitive impairment and cognitively intact mental status, providing a critical window for implementing preventive interventions to delay objective cognitive decline. AIMS: We aimed to develop a predictive model for SCD progression in older adults with mild cognitive impairment (MCI). This model will facilitate the identification of risk factors and establishment of targeted interventions for community-based SCD management. METHODS: Data from the China Health and Retirement Longitudinal Study (CHARLS) was utilized in this study, extracting 18 indicators. Potential predictors selected through univariate Cox regression and LASSO regression analyses were sequentially incorporated into a multivariable Cox regression model. A nomogram was constructed to establish a predictive model. Model validation encompassed Area Under Curve (AUC) metrics for discriminative capacity, complemented by quantitative assessments using calibration curve analysis for precision verification and decision curve analysis (DCA) for clinical utility evaluation. RESULTS: A total of 1099 older adults with SCD were included in the final analysis, of whom 114 (10.3%) developed MCI. Multivariable Cox regression identified residence, marital status, educational level, social participation, gait speed, and baseline cognitive function. The model demonstrated time-dependent AUC values of 0.885, 0.830, 0.839, and 0.836 in the training set when evaluating discriminative capacity at 2-, 4-, 7-, and 9-year, respectively. The predictive model showed excellent predictive ability according to AUC, calibration curve, and DCA. CONCLUSIONS: A predictive model was created to estimate the risk of developing MCI in older individuals with SCD, offering clinician-actionable intervention benchmarks for preventive care.

Humans↗
PubMed1985

A microtiter plate enzyme-linked immunosorbent assay for measuring C3b receptors on human erythrocytes.

An enzyme-linked immunosorbent assay was developed for quantitation of complement C3b receptors (C3bR) on human erythrocytes fixed in monolayer to microtiter plates. The disadvantages of macro test tube systems (large consumption of sample material and reagents, tedious washing procedures, cell loss and hemolysis) were avoided, and the fixed cells could be stored. In return a modest reduction in antigenicity induced by glutaraldehyde was inevitable. The calibration curve expressed a detection limit of about 10% and discrimination between levels of C3bR in the interval of about 10-120% of a standard erythrocyte with a high uptake of anti-C3b-receptor antibodies. The determinations of C3bR in normals as well as in patients varied within these limits, and showed a preponderance of low levels in the patients. The between-day coefficient of variation was 10.3%; the within-assay interplate and intraplate determinations respectively gave coefficients of variation of 9.7% and 6.2%. The method is suitable for further development and use for investigation of erythrocyte-bound immune complexes.

Antibodies, Monoclonal↗
PubMed1989

A new method for the estimation of C3d. Affinity clearance of C-determinant-bearing C3 molecules and fragments followed by estimation of C3d by ELISA.

A method is described to quantitate human complement fragment C3d. Test samples were treated with a predetermined excess of anti-C3c-Sepharose beads in the presence of EDTA to remove all the C-determinant-bearing C3 molecules or fragments. C3d left in the supernatant was then estimated by ELISA. Using this method, C3d could be estimated accurately in normal plasma samples. A good correlation (r = 0.93) was observed between C3d values obtained by this method and values obtained by the widely used method of Perrin and coworkers. The average C3d plasma concentration was 2.8 mg/l (SD = 0.7 mg/l, n = 21). The interassay coefficient of variation using a normal plasma pool (C3d 2.7 mg/l) was 8.3% and using normal plasma pools in which the C3d concentrations were raised to 10.3 and 17.4 mg/l by the addition of aged normal serum the levels were 8.0 and 7.5% respectively. Intra-assay coefficients of variation with these samples were 4.6, 3.0 and 2.8%, respectively. 16 patients with renal dysfunction had C3d levels in the range of 4.3-10.0 mg/l and 15 patients undergoing continued ambulant peritoneal dialysis had levels of 3.3-12.2 mg/l. The C3d content in peritoneal dialysate of patients undergoing dialysis varied from 9.3 to 383 micrograms/l.

Antibody Specificity↗
PubMedDate not supplied

Reflections on nurse-midwifery role and functions.

The role and functions of nurse-midwifery are currently being studied by the American College of Nurse-Midwives Certification Council. The remarks that were included on the comment sheet and comments included on the margins of the survey forms were subjected to content analysis. These narrative data complement the quantitative data derived from the research. They reflect a capsule view of contemporary role conflict in nurse-midwifery.

Data Collection↗
PubMed1997

Use of predictive microbiology in meat hygiene regulatory activity.

New Zealand is a supplier of refrigerated raw meat to world markets. To maintain this supply, from regulatory and commercial perspectives, production standards need to deliver products that are both hygienically adequate and commercially viable. A dynamic Temperature Function Integration (TFI) model, as a form of predictive microbiology, was used jointly by regulators and processors to develop justifiable criteria for the management of refrigeration during the production of hot and warm-boned meat, the post-slaughter handling of ovine carcasses and the handling of offals. Current processes operating according to accepted standards for Good Manufacturing Practice (GMP) were quantified in terms of TFI. The hygienic adequacy of new processes were similarly determined using the TFI model and compared to relevant GMP standards. From a regulatory perspective, the dynamic TFI model has provided a rapid and cost effective method of quantifying a temperature dependent process in terms of the potential for microbial proliferation. It has also produced a method for determining parameters for new or intended processes by comparing the potential for microbial proliferation with previously validated outputs, and has complemented traditional quantitative microbiology to provide a rapid, cost effective method of verifying that a process is performing according to design parameters. However, it could not be used to validate standards for processing in the absence of existing standards for GMP, or in the absence of microbial standards previously established using the principles of risk assessment.

Animals↗
PubMed1981

Semi-quantitative analysis of immunoglobulins and complement fractions 3 and 4 in the jejunal mucosa in coeliac disease and in food allergy in childhood. Immunohistochemical study by light and electron microscopy.

Immunoglobulins A, M, G and E and complement fractions 3 and 4 in jejunal biopsy specimens of 14 children were stained by the peroxidase-labelled antibody technique and studied in light and electron microscopy. In addition, cryostat sections were stained with FITC-conjugated anti-C3,-C4 and -IgE sera. Five patients had coeliac disease, three intestinal cow's milk or rye allergy, three eczema due to food allergy, and in three patients, who served as controls, intestinal and immunological diseases were excluded. This study showed that increased amounts of IgA and IgM both in coeliac disease and in food allergy are produced by the plasma cells in the lamina propria of the jejunum and are secreted into the gut through the epithelial cells in a similar manner as in the morphologically normal intestine. The amount of IgG produced locally or derived from serum, was increased in coeliac disease. IgE-producing cells were rare in all patients. No deposits of complement were seen in the basement membranes or epithelial cells.

Animals↗
PubMed1973

Antibody to HSV-2 induced tumor specific antigens in serums from patients with cervical carcinoma.

Antibody distinct from that involved in neutralization and directed to an antigen (AG-4) induced in HEp-2 cells by infection with herpesvirus type 2 was identified in serums from patients with cervical carcinoma by means of a quantitative micro complement fixation test. The presence of antibody to AG-4 correlates well with the extent of the tumor; antibody is virtually absent in matched control women and in women with therapy and without recurrent neoplasia. Reactivity is not observed with control antigen consisting of a cell extract prepared from uninfected HEp-2 cells. The possible prognostic significance of this antibody and its implications are discussed.

Adult↗
PubMed1967

Immunological studies on dermatophytes. I. Serological reactivities of neutral polysaccharides with rabbit antiserum to Microsporum quinckeanum.

Antiserum produced in the rabbit to autoclaved mycelial suspensions of Microsporum quinckeanum reacted with three neutral polysaccharides isolated from each of five species of dermatophytes, M. quinckeanum, Trichophyton granulosum, T. interdigitale, T. rubrum, and T. schönleinii. The serological reactivities of these polysaccharides, grouped as galactomannans I, galactomannans II, and glucans, were compared by qualitative precipitation analyses in gel and quantitative complement-fixation analyses. Significant differences were found among the glucans and galactomannans II but not among the galactomannans I of these species.

Complement Fixation Tests↗
PubMed1968

Immunological studies on dermatophytes. II.

The contribution of terminal galactofuranose residues to the antigenic specificity and to cross-reactivity of galactomannans isolated from five species of dermatophytes, Microsporum quinckeanum, Trichophyton granulosum, T. interdigitale, T. rubrum, and T. schoenleinii, was investigated. Galactofuranose units were removed from galactomannans I and galactomannans II by mild acid hydrolysis. The resulting mannans were tested for serological reactivity with rabbit antiserum to M. quinckeanum by qualitative precipitation in gel and by quantitative complement-fixation analyses. Our results showed that, with this antiserum, the galactofuranose residues contributed greatly to the antigenic specificity and to cross-reactivity of the galactomannans II, but these residues were less significant as antigenic determinants in the galactomannans I. We have shown that mannans isolated from three Candida species reacted with rabbit antiserum to M. quinckeanum.

Antigens↗
PubMed1978

Comparison of an enzyme-linked immunosorbent assay for quantitation of rotavirus antibodies with complement fixation in an epidemiological survey.

The development of a micro-scale enzyme-linked immunosorbent assay (ELISA) with horseradish peroxidase as the marker enzyme for the detection and measurement of human rotavirus antibodies is described. A semipurified preparation of the serologically related simian agent, SA-11 virus, was used as the antigen. Test sera were reacted with antigen-sensitized wells in disposable poly-vinyl microplates. Any attached antibody was detected by the addition of peroxidase-labeled anti-species immunoglobulin (conjugate) followed by assay of the enzyme reaction with its substrate, hydrogen peroxide plus 5-aminosalicylic acid. This micro-ELISA was compared with complement fixation in a seroepidemiological study of the age prevalence of rotavirus antibody in Aboriginal and European populations living in the same outback area in Australia. The ELISA (results read with the naked eye) proved to be approximately 16 times more sensitive than complement fixation. Of Aborigines, 71% had rotavirus complement-fixing antibody, as compared to 45% of Europeans. By ELISA 100% of both populations had rotavirus antibodies. Mean antibody titers in the different age groups were higher in Aborigines than in Europeans. Antibody levels rose steeply throughout the first 20 years of life, remained high during the next 20 years, then increased again at least up to the age of 60 years. The micro-ELISA was practical, simple to perform, and more suitable than complement fixation for large seroepidemiological rotavirus studies. It also has potential for serodiagnosis of the disease, both in the laboratory and in the field.

Adolescent↗
PubMed1978

Quantitative influence of antibody and complement coating of red cells on monocyte-mediated cell lysis.

Monocyte-mediated lysis in vitro of human red cells coated with measured amounts of immunoglobulin G (IgG) or complement were studied. 1,000-1,500 molecules of IgG anti-D are necessary to effect measurable lysis, and lysis increases linearly with increasing levels of antibody sensitization. 100 microgram/ml of IgG1 abolished lysis even at maximal levels of anti-D sensitization (15,000 molecules/cell). Two isoimmune IgG anti-A or anti-B antisera were 5 to 10-fold less efficient in promoting phagocytosis or lysis per molecule of IgG bound; however, because of the greater antigen density of A or B, more than 100,000 molecules IgG/cell could be bound, producing equivalent lysis to anti-D-coated cells. Although inhibition by IgG1 was similar at equivalent levels of sensitization with anti-A, anti-B, or anti-D at high levels of coating with anti-A or anti-B (not attainable with anti-D), lysis was not inhibited by IgG1. Cells coated with human complement components alone were not lysed by monocytes; however, complement coating augmented IgG-mediated lysis and reduced the quantity of anti-D necessary to produce lysis to less than 1,000 molecules/cell. After thorough degradation of C3b by serum to C3d, complement augmentation persisted.

ABO Blood-Group System↗
PubMed1984

Histochemical localization of estrogen and progesterone receptors: evaluation of a method.

A histochemical method for the detection of estrogen (ER) and progesterone (PR) receptors in human endometrium, using estrogen and progesterone derivatives linked to fluorochrome-labeled bovine serum albumin (E2-BSA-fluorescein isothiocyanate (FITC) and progesterone-BSA-tetramethylrhodamine isothiocyanate (TMRITC], has been evaluated. The fluorochrome-labeled steroids were bound to the cytoplasm--preferably in glandular epithelial cells but to a lesser extent also to stromal cells. The steroid specificity of the observed binding was studied by preincubating the sections with a series of unlabled steroids and nonsteroidal, hormonally active compounds (estradiol-17 beta, diethylstilbestrol, tamoxifen, 5 alpha-dihydrotestosterone and R 1881 for ER and ORG 2058, R 5020, dexamethasone, cortisol and 5 alpha-dihydrotestosterone for PR). The inhibition studies indicated that E2-BSA-FITC and progesterone-BSA-TMRITC bind to ER and PR in human endometrium with a reasonable degree of specificity. The method was reproducible and various procedural steps were tested, showing satisfactory technical stability. The method is applicable to small tissue samples, and is a valuable complement to quantitative biochemical receptor assays, as it localizes the receptors in tissue slices.

Binding Sites↗