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B Ungar

Publications and source records attributed to B Ungar.

At least 19 recordsLinked to original sources
PubMed1999

Regional seroprevalence of Cryptosporidium parvum-specific IgG of cats in the United States.

The objective of this study was to determine the regional prevalence of Cryptosporidium parvum-specific IgG in the sera of cats in the United States. The continental United States was partitioned into eight regional areas. Serum samples from 75 cats from each region were assayed for C. parvum-specific IgG using an indirect enzyme-linked immunosorbent assay (ELISA). Age, sex, breed, and indoor/outdoor status were examined as possible risk factors for developing a positive C. parvum-specific IgG antibody titer. The presence of gastro-intestinal signs and Toxoplasma gondii-specific IgG in the serum were also evaluated for association with C. parvum seropositivity. Of the 600 samples assayed, 50 (8.3%) were positive for C. parvum-specific IgG. Regional seroprevalence ranged from 1.3% in the mid-Atlantic states to 14.7% in the south-eastern states. The oldest group of cats (>10 years) had the highest seroprevalence (15.3%). The prevalence of C. parvum-specific IgG was higher among male (10.1%) than among female cats (6.9%), although, the difference was not statistically significant (p = 0.17). Seropositivity was not associated with pure-bred status. C. parvum-specific IgG antibodies was detected most frequently in T. gondii-specific IgG seropositive cats, outdoor cats, and cats with gastro-intestinal signs. These results suggest that cats in the United States are commonly exposed to C. parvum.

Age Factors↗
PubMed1997

Enzyme-linked immunosorbent assay for the detection of Cryptosporidium parvum IgG in the serum of cats.

The objective was to develop an enzyme-linked immunosorbent assay (ELISA) for the detection of Cryptosporidium parvum IgG in the serum of cats. The ELISA was an indirect ELISA using soluble C. parvum oocyst antigens and a peroxidase-labeled anti-feline IgG secondary antibody. Sera from cats with Toxocara felis, Giardia spp., Aelurostrongylus abstrusus, Isospora felis, Isospora rivolta, Toxoplasma gondii, or Taenia spp. infections were assayed in specificity studies. Following optimization, the ELISA and fecal examination for oocysts were performed on samples from 170 client-owned or humane society source cats and 1 cat inoculated orally with C. parvum oocysts. Cryptosporidium parvum oocysts were detected in feces (4/170; 2.4%), and C. parvum IgG was detected in serum (26/170; 15.3%) from naturally exposed cats. The seroprevalence data suggest that some cats in the geographical area studied were exposed to C. parvum, but persistent oocyst shedding was less common. The ELISA is not useful for predicting oocyst shedding in individual cats.

Animals↗
PubMed1986

Immunological abnormalities in asymptomatic homosexual men: correlation with antibody to HTLV-III and sequential changes over two years.

A prospective study on 100 homosexual male volunteers was designed to examine immunological function in relation to sexual activity and infection with the human T cell lymphotropic virus Type III (HTLV-III). Complete data were available for 71 men. In a comparison with 100 age-matched heterosexual men, the study group of 100 men had a significantly higher mean serum IgG level (12.1 +/- SD 2.7 g/l vs. 10.9 +/- 2.4 g/l, p less than 0.01) and a significantly lower mean number of CD4 (T4) cells (845 +/- 310 X 10(-6)/l vs. 1128 +/- 375; p less than 0.01). For the study group, seropositivity for anti-HTLV-III was present initially in 22 per cent and was associated with a higher mean level of serum IgG and lower mean number of CD4 cells. Among seropositive homosexual men a low CD4/8 ratio was attributable to low numbers of CD4 cells in those without lymphadenopathy and to high numbers of CD8 cells in those with lymphadenopathy. For the seronegative homosexual men, a low CD4/8 ratio as a result of an increased CD8 cell count was present in 12 of 60, and was associated with numerous sexual partners and semen culture positive for cytomegalovirus. In two seropositive subjects a low CD4/8 ratio due to a decrease in the CD4 cell count was predictive of the development of AIDS by some two years. For the 71 men with complete data over two years, indices of cell-mediated immunity, including mean counts of CD4 cells, the CD4/8 ratio, and score for recall of cutaneous delayed type hypersensitivity increased during the first year but not during the second year in both seropositive and seronegative subjects. These increases occurred in association with changes in sexual practices and activity, but could not be attributed to any one particular factor.

AIDS-Related Complex↗
PubMed1985

Autoantibody to the gastrin receptor in pernicious anemia.

We examined serum IgG fractions from 20 patients with pernicious anemia and 25 control subjects for their capacity to inhibit binding of [125I]15-leu human gastrin-17 to parietal-cell-enriched gastric mucosal cells. IgG fractions from six patients reduced gastrin binding by 45.6 +/- 12.2 per cent, as compared with a reduction of 1.8 +/- 0.7 per cent by fractions from the 25 controls. The fractions from these six patients also reduced gastrin-stimulated [14C]aminopyrine uptake by gastric cells (an index of gastric acid secretory activity in vitro) by 50.2 +/- 8.4 per cent (mean +/- S.D.), as compared with 9.2 +/- 4.1 per cent for the controls. IgG fractions from six other patients that did not reduce gastrin binding also inhibited gastrin-stimulated [14C]aminopyrine uptake, by 48.1 +/- 9.1 per cent. These reductions in gastrin binding and aminopyrine uptake were abolished by absorption of the IgG fractions with suspensions of viable gastric mucosal cells but not by absorption with liver or kidney cells. The IgG fractions did not inhibit [3H]histamine binding or histamine-stimulated [14C]aminopyrine uptake. These results suggest that serum IgG from some patients with pernicious anemia contains autoantibodies to the gastrin receptor.

Adult↗
PubMed1985

Serum from patients with pernicious anaemia blocks gastrin stimulation of acid secretion by parietal cells.

We examined 51 sera from patients with pernicious anaemia for their capacity to block maximal gastrin stimulation of acid secretion by isolated rodent gastric parietal cells. 14C-aminopyrine accumulation was used as the index of acid secretion in vitro. Sera from patients with pernicious anaemia gave significantly (P less than 0.005) more block of maximal gastrin stimulation of acid secretion (61.7 +/- 37.8%) than sera from 10 patients with systemic lupus erythematosus (19.6 +/- 17.7%), 10 with scleroderma (34.2 +/- 22.3%), five with rheumatoid arthritis (22.4 +/- 15.6%) or 30 from healthy persons (27.4 +/- 12.8%). Maximal histamine stimulation of acid secretion was not inhibited. The blocking factor was present in serum IgG fractions, and serum and IgG fractions gave parallel dose-response and dilution curves. The serum block was abolished by absorption with gastric mucosal cells and correlated with the presence of parietal cell surface autoantibody. We conclude that serum immunoglobulin in pernicious anaemia can block gastrin stimulation of acid secretion and suggest that this block may be mediated by competition with gastrin for surface receptors on parietal cells.

Adult↗
PubMed1985

65-70 kD protein identified by immunoblotting as the presumptive gastric microsomal autoantigen in pernicious anaemia.

Sera from 20 of 24 patients with pernicious anaemia reacted by immunoblotting with a 65-70 kD protein in canine and rodent gastric mucosal cells enriched for 80-90% parietal cells, and in microsomal preparations derived from these cells. All 20 reactive sera were positive for parietal cell microsomal antibody demonstrated by immunofluorescence. Eighteen parietal cell microsomal antibody-positive sera from patients with unconfirmed pernicious anaemia also reacted with the same 65-70 kD protein. Serum reactivity with the same 65-70 kD protein was not seen with canine and rodent liver cells or with microsomal preparations derived from these cells. Sera from 10 patients with chronic active hepatitis, 10 with scleroderma and 10 with rheumatoid arthritis and 22 healthy persons did not react with the 65-70 kD protein. These results suggest that the 65-70 kD protein is probably the parietal cell microsomal autoantigen. A second antigen of 85-90 kD mol. wt. present only in canine gastric mucosal preparations also correlates with the presence of parietal cell microsomal antibody. However, the contribution of this second antigen to parietal cell microsomal antibody reactivity remains uncertain.

Anemia, Pernicious↗
PubMed1983

Autoantibodies cytotoxic to gastric parietal cells in serum of patients with pernicious anemia.

We measured the complement-dependent cytotoxic activity of serum in 60 patients with pernicious anemia. Canine gastric mucosal cells served as the indicator of cytotoxicity, which was expressed as a percentage of the maximal effect produced by a cytolytic agent (Triton X-100). Serum from patients with pernicious anemia showed a higher average activity (11.8 +/- 10.3 per cent, P less than 0.001) than serum from 29 patients with systemic lupus erythematosus (1.0 +/- 1.8 per cent), 10 with scleroderma (0.1 +/- 0.1 per cent), 10 with rheumatoid arthritis (0.6 +/- 0.6 per cent), 22 with multiple sclerosis (0.4 +/- 1.2 per cent), and 23 with chronic persistent hepatitis (0.03 +/- 0.1 per cent), and serum from 64 healthy persons (0.4 +/- 1.0 per cent). Serum from patients with pernicious anemia was not toxic to canine liver or kidney cells. Absorption with gastric mucosal cells and heat inactivation of complement abolished the cytotoxic reaction. The cytotoxic factor resided in the IgG fraction of immunoglobulin, and the amount of cytotoxicity was proportional to the IgG concentration. Cytotoxic activity correlated with the presence of parietal-cell-surface--reactive autoantibody demonstrated by immunofluorescence. We conclude that cytotoxic autoantibodies to parietal cells may contribute to the loss of such cells from the gastric mucosa of patients with pernicious anemia.

Adult↗
PubMed1983

Parietal cell surface reactive autoantibody in pernicious anaemia demonstrated by indirect membrane immunofluorescence.

We examined, in a 'double blind' study, 60 sera from patients with pernicious anaemia for immunofluorescence reactivity with the surface membranes of viable parietal cells isolated from dog stomachs. Fifty-three sera (88%) gave an IgG autoantibody reaction with the surface membranes of parietal cells. Surface staining was also seen with parietal cells from monkey, pig, rat and mouse. The parietal cell surface reactive autoantibody was not found in any of 14 sera from patients with chronic active hepatitis, 10 from patients with systemic lupus erythematosus and 50 from healthy persons. The surface reactivity autoantibody was present in 13 of 14 sera without parietal cell microsomal antibody, 28 of 31 sera without intrinsic factor antibody and in four of four sera without microsomal and intrinsic factor antibodies. Absorption with parietal cell enriched gastric mucosal cells neutralized the activity of the surface reactive but not the microsomal antibody and cross absorption with gastric microsomes neutralized the activity of the microsomal but not the surface reactive antibody. Surface staining of parietal cells was not abolished by absorption with dog or rat hepatocytes, dog or rat kidney cells, human fibroblasts or human AB red blood cells. The results suggest that the parietal cell surface reactive antibody is probably different from the microsomal antibody. Immune reactions of the cell surface reactive antibody with parietal cell surface antigens may play a role in the pathogenesis of the gastric lesion in pernicious anaemia.

Adult↗
PubMed1983

Flow microfluorimetric analysis of autoantibody reactions with parietal cell surface membranes in pernicious anaemia.

Using flow microfluorimetry (FMF), 60 sera from patients with pernicious anaemia (PA) were examined for immunoreactivity with the surface membranes of viable canine parietal cells. FMF analyses showed that the percentage of parietal cells giving a surface staining reaction with a fluorescence intensity greater than 50 arbitrary units was 44.5 +/- 17.5% for sera from 60 patients with PA compared to 13.7 +/- 2.7% for sera from 14 patients with chronic active hepatitis, 10.7 +/- 6.7% for sera from 10 patients with systemic lupus erythematosus and 16.5 +/- 4.4% for sera from 50 healthy persons. Surface staining detected by FMF was restricted to parietal cells and abolished by absorption with parietal cell enriched preparations but not by absorption with dog or rat hepatocytes, dog or rat kidney cells, human fibroblasts, human AB red blood cells or dog gastric microsomes. The intensity of the parietal cell surface staining reactions correlated with the presence of antibody reactions with parietal cell surfaces previously demonstrated by immunofluorescence microscopy but did not correlate with the presence of microsomal or intrinsic factor autoantibodies. The results provide further support for the presence of a parietal cell surface reactive autoantibody distinct from the conventional parietal cell microsomal autoantibody.

Anemia, Pernicious↗
PubMed1981

HLA-DR patterns in pernicious anaemia.

The pattern of HLA-DR antigens was studied in a group of 66 patients with Addisonian pernicious anaemia, comprising a subgroup of 18 patients with associated endocrine disease and a subgroup of 48 patients with no associated endocrine disease. Compared with a control group of 120 subjects all 66 patients showed an increase in HLA-DR2 and DR4 and a decrease in DR3 (p less than 0.02). Significant differences were also found between the endocrine and non-endocrine subgroups for patterns of HLA-DR antigens (p less than 0.005) and for pairwise combinations of HLA-DR antigens (p less than 0.01). Relative to controls, the endocrine subgroup showed an increase of HLA-DR3/DR4 (relative risk 4.0), contrasting with an increase of HLA-DR2/DR4 (relative risk 6.85) and DR4/DR5 (relative risk 5.38) in the non-endocrine subgroup. These observations suggest that HLA-DR antigens or closely linked genes may interact to influence susceptibility to pernicious anaemia (or endocrine disease, or both). Thus interactive effects related to HLA-DR2/DR4 and DR4/DR5 may predispose to pernicious anaemia without endocrine disease, whereas interactive effects related to HLA-DR3/DR4 may predispose to pernicious anaemia in association with endocrine disease.

Adult↗
PubMed1980

Adult non-endemic Burkitt's lymphoma. An Australian case report.

This report describes the occurence in Australia of non-endemic Burkitt's lymphoma in a 43-yr-old European migrant. The patient presented with cervical lymphadenopathy and massive bone marrow involvement, and died 6 mth later with intracranial spread of the tumour. The pathological features, course and treatment of the disease are described.

Adult↗
PubMed1979

Two cases of carcinoma of the lung characterized by a bone marrow agar culture pattern resembling acute myeloid leukemia.

In vitro agar culture patterns of bone marrow cells in acute myeloid leukemia may show several growth patterns, including cultures where no colonies or clusters develop, cultures with varying numbers of clusters and no colonies, or colony and cluster formation with an extremely high ratio of clusters to colonies. Twelve cases of carcinoma of the lung are described, of which two show an in vitro growth pattern of cluster formation alone, characteristic of that seen in acute myeloid leukemia. The remaining ten patients showed slightly reduced colony numbers compared to normal.

Bone Marrow↗
PubMed1979

Non-enzymic interactions of nicotinamide adenine dinucleotide, of some of its synthetic analogues and other compounds with orthophosphate.

Changes in the ultraviolet (UV) absorption spectra of nicotinamide adenine dinucleotide (NAD), of its synthetic analogues, and of adenosine and its derivatives in the presence of high concentrations of orthophosphate were studied. The role of the carboxamide group of the nicotinamide moiety of NAD on these spectral changes was investigated by replacing that group with an acetyl or aldehyde group. The effect of the 6-amino group of the purine was investigated by studying the interaction of deamino-NAD and various adenosine derivatives with orthophosphate. 2,4-Dinitrophenol was also found to give a charge transfer complex with phosphate. Molar extinction coefficients (E) and association constants (K) of these charge transfer reactions were determined.

Adenine Nucleotides↗
PubMed1978

Lymph node and splenic imprints: their value in diagnosis.

Comparison was made of the value of information obtained from imprints and from histological sections of lymph nodes from 100 biopsies on patients with mainly haematological disorders and 55 spleens removed surgically. The sections provided the definitive diagnosis. It was seldom possible to make a definite diagnosis from imprints, but they provide additional information useful in interpreting the histology of sections.

Hematologic Diseases↗
PubMed1978

Preliminary studies of the sodium borohydride stabilizable binding of phenylethylamine and tyramine to brain preparations.

The borohydride stabilizable binding of 2-phenylethylamine and p-tyramine to mouse brain homogenates was compared to that of tryptamine and of serotonin. The highest binding was found to be that of tryptamine, followed by that of serotonin, tyramine, and phenylethylamine. The stabilizable binding of phenylethylamine to calf midbrain (including corpus striatum) homogenates and synaptic membranes was decreased by dopamine; this amine and D-amphetamine also decreased the stabilizable binding of tyramine to rat brain homogenates. The subsynaptosomal distribution of the binding of phenylethylamine to synaptic calf midbrain fractions was also investigated. The highest binding capacity was found in the 0.8 M fraction, rich in myelin.

Animals↗
PubMed1977

HLA patterns in pernicious anaemia.

The pattern of HLA antigens was studied in 127 patients with Addisonian pernicious anaemia. The pattern in the whole group of patients differed significantly from that in 586 controls. But different subgroups of the patients had different HLA antigens. Among 27 patients with anaemia associated with endocrine disease there was an increased frequency of HLA-B8, B18, and BW15. The remaining 100 patients, who did not have endocrine disease, showed increased frequencies of HLA-B7 and B12. The positive association with HLA-B12 among this subgroup was confined to 62 patients with severly impaired vitamin B12 absorption, including 13 patients with vitamin B12 neuromyelopathy, who had the highest frequencies of HLA-B7 and B12. The significant heterogeneity in HLA patterns in different clinical subgroups of these patients indicates genetic heterogeneity in pernicious anaemia and explains previous discrepancies in the associations between HLA antigens and pernicious anaemia.

Anemia, Pernicious↗
PubMed1977

Tyramine-binding by synaptosomes from rat brain: effect of centrally active drugs.

Incubation of p-tyramine (TRM) with rat midbrain plus corpus striatum (MB+ CS) crude synaptosomal preparations, under conditions which reduce to a minimum amine uptake, results in appreciable binding of this amine by synaptosomes. This process is inhibited by preincubation with a number of drugs active in the CNS, e.g., chlorpromazine, desipramine, d-amphetamine, and diphenhydramine. Morphine, however, does not affect this binding. The Ki for each one of these compounds, as well as the K association constant and concentration of the binding sites of TRM, were determined. These results suggest a role for TRM in synaptic transmission mechanisms occurring in the nigrostriatal system, a function which could be regulated by a number of substances representing some of the major chemical classes of centrally active drugs (CD).

Animals↗