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C B Daul

Publications and source records attributed to C B Daul.

31 records · Page 2Linked to original sources
PubMed1986

Immunologic studies in homosexual and hemophiliac subjects with persistent generalized lymphadenopathy: a comparative analysis.

Hemophiliac patients receiving factor VIII replacement therapy and homosexual subjects are at risk for the acquired immune deficiency syndrome. Immunologic abnormalities, especially depletion of helper T cell populations, have been noted in members of these groups and may parallel their clinical state. We have evaluated the peripheral blood immunologic status of a group of hemophiliac and homosexual subjects with and without persistent generalized lymphadenopathy (PGL). Although individuals with PGL had more abnormal T-lymphocyte parameters, including lower helper/suppressor ratios, than group members without lymphadenopathy, there were no significant differences noted within each respective risk group. However, differences between hemophiliac and homosexual patient groups were noted. T-lymphocyte subpopulations of hemophiliac patients with lymphadenopathy were significantly more abnormal than the corresponding homosexual groups. All groups had decreased lymphocyte proliferative responses to mitogen. Homosexual subjects with lymphadenopathy exhibited the most profoundly depressed lymphocyte mitogenic responses. We conclude that, although abnormalities of T-lymphocyte subpopulation and lymphocyte mitogenic responses exist within each risk group, homosexual subjects (both asymptomatic and with PGL) had lower mitogenic responses than would be expected for their T-lymphocyte helper/suppressor ratios as compared to either control subjects or hemophiliac patients. These findings suggest that additional factors are operative in the mononuclear cell populations of homosexual subjects that depress lymphocyte function. An analysis of these factors may help explain the higher incidence of AIDS in homosexual subjects as compared to hemophiliac patients.

Acquired Immunodeficiency Syndrome↗
PubMed1985

Hypersensitivity reactions to ingested crustacea: clinical evaluation and diagnostic studies in shrimp-sensitive individuals.

Adverse reactions to ingested crustacea are common and may be life-threatening. We studied 14 individuals with histories of such reactions to shrimp by immediate skin tests and RAST with extracts of shrimp, crab, crayfish, and lobster. Nine of these subjects (8/8 atopics and 1/6 nonatopics) had positive immediate skin tests (wheal greater than or equal to 2 mm) and RAST (ratios greater than 3.0) to shrimp. Their skin tests and RAST ratios to the other crustacea were also frequently positive even, in several cases, in the absence of prior exposure. In contrast, only 1/10 volunteers with no history of intolerance to crustacea had a weak positive skin test to raw shrimp. These studies suggest that both skin tests and RAST are useful in the confirmation of hypersensitivity to shrimp in atopic individuals and that cross-reactivity among crustacea may exist.

Adult↗
PubMed1985

Persistent lymphadenopathy associated with hypertransfusion in sickle-cell disease.

We report the results of an immunologic evaluation of two hypertransfused (HT) patients with sickle-cell disease (SCD) who have developed persistent generalized lymphadenopathy. In order to interpret the results of this evaluation, we studied seven other HT patients with SCD and seven nonhypertransfused patients with SCD. Patients with SCD had decreased percentages of T-lymphocytes to include both helper and suppressor subsets in their peripheral blood. These decreases resulted in T helper/suppressor ratios not different from those of healthy normal control subjects. Lymphocyte proliferative responses to mitogen were decreased in the nonhypertransfused group, whereas mononuclear cell populations from both patient groups had higher levels of spontaneous suppressor cell activity than did control subjects. The patients with lymphadenopathy were distinguished from other HT sickle-cell anemia patients by immunologic abnormalities that included decreased percentages of T4+ lymphocytes, decreased T helper/suppressor ratios, and decreased lymphocyte responses to mitogen. Furthermore, the serum of these patients contained antibody specific for human T cell lymphotropic virus type III (HTLV-III). We believe that these two patients have developed acquired immunodeficiency syndrome-related lymphadenopathy as the result of transfusion-acquired HTLV-III. We propose that hypertransfusion treatment in SCD, possibly in association with phenytoin administration, places individuals at risk for HTLV-III-associated syndromes.

Adolescent↗
PubMed1985

A longitudinal immunologic evaluation of hemophiliac patients.

Over an average span of one year, we performed a prospective clinical and immunologic evaluation of 30 patients with hemophilia. No patient developed life-threatening opportunistic infection or malignancy; however, the immunologic abnormalities and lymphadenopathy initially present in nine patients (lymphadenopathy group) persisted. In addition, five patients, representing 24% of the initial group without lymphadenopathy, developed generalized lymphadenopathy (converter group). One episode of idiopathic thrombocytopenia (ITP) and one episode of staphylococcal sepsis occurred in this "converter" group; one episode of ITP also occurred in the lymphadenopathy group. Sixteen patients remained asymptomatic. At the time of the follow-up evaluation, those differences in mononuclear cell (MNC) percentages and numbers noted initially among the three hemophiliac groups were no longer present. Natural killer cell function alone or in the presence of biologic response modifiers was not different among hemophiliac and control groups. Before developing lymphadenopathy, the converter group of patients had significantly better lymphocyte mitogenic function than did the other two groups of patients with hemophilia. However, lymphocyte mitogenic responses of all groups of patients with hemophilia significantly deteriorated over the course of the study. The abnormal mitogenic responses noted in these patients was explained in part by higher levels of spontaneous suppressor cell activity in mononuclear cell preparations from patients with hemophilia. We conclude that long-term immunologic studies of this patient population requires both quantitative and qualitative evaluations. Our data show that patients with hemophilia have progressive dysfunction of cell-mediated immunity.

Adolescent↗
PubMed1984

Acquired immune deficiency syndrome (AIDS). Medical challenge of the 80's.

Although the pathophysiology of acquired immune deficiency syndrome (AIDS) is not completely understood, we know a great deal about its epidemiology, risk factors, clinical manifestations, course, and immunologic features. Clinicians caring for high-risk individuals, particularly those in endemic urban areas, should remain alert for signs and symptoms of opportunistic infections or neoplasms associated with immunosuppression. It is clear that research on AIDS has increased exponentially; both physicians and patients should be encouraged by the fact that the apparent cause of this syndrome has been identified (human T-lymphotropic retrovirus HTLV-III) and that this breakthrough should result in effective therapeutic strategies in the near future.

Acquired Immunodeficiency Syndrome↗
PubMed1983

Acquired immune deficiency syndrome: an update and interpretation.

It is clear that there is a distinct new clinical entity of acquired immune deficiency which manifests itself by opportunistic infections and KS. It occurs in selected groups of the population but with an ever increasing spectrum. The clinical presentation is extremely varied and the spectrum of disease runs a wide gamut. Health professionals should be aware that there is a large pool of individuals at risk for AIDS; also AIDS may manifest itself in the limited forms with mild initial signs which continue for months before serious disease becomes apparent. There is at present no specific diagnostic laboratory test to identify these patients or those at greatest risk. Present evidence indicates that once life-threatening opportunistic infections or KS have become obvious, although the disease process may wax and wane, most patients follow an inexorable downhill course. That process has not been reversed by presently applied therapies. In view of the failure of conventional and experimental therapies, the only treatment appears to be prevention of disease by avoiding risk factors. With the ever increasing number of possible risk factors identified, such avoidance becomes continually more difficult. The most pressing problem is to delineate the pathogenesis of AIDS. Until then optimal preventive and therapeutic interventions can not be instituted fully. There are a number of major unanswered questions, foremost of which is the nature of the transmittable agent. Moreover, it is not entirely clear who is susceptible to this agent. With the vast numbers at risk and growing numbers of AIDS cases, it is imperative to uncover the initial events responsible for this syndrome. From the public health point of view, it is also crucial to determine whether those individuals in the high risk groups which exhibit immunological abnormalities will, given a long enough latent period, eventually progress to AIDS/KS or whether the majority are merely a forme fruste of AIDS. Because of the major public health impact of AIDS, all physicians should be aware of and knowledgeable about this new disease process.

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

Seroconversion to human immunodeficiency virus (HIV) in hemophiliacs. Relation to lymphadenopathy.

The authors studied the natural history of human immunodeficiency virus (HIV) exposure in 187 hemophiliacs followed for an average of 45 months. Overall, 55 percent developed antibody specific for HIV and 21 percent developed persistent generalized lymphadenopathy. Most patients seroconverted sometime between early 1982 and the end of 1984. Four patients developed acquired immune deficiency syndrome (AIDS) and four seropositive patients developed idiopathic thrombocytopenia (ITP). One of the four patients who developed AIDS and three of the four with ITP had preexisting lymphadenopathy. None of the 10 patients with lymphadenopathy or the 20 asymptomatic patients was seropositive for human T-lymphotropic virus, type I. Although seropositivity and lymphadenopathy have been found in many of the authors' patients, few have developed clinical disease that can be related to HIV infection.

AIDS-Related Complex↗
PubMedDate not supplied

Antigenic analysis (IgE and monoclonal antibodies) of the major shrimp allergen Pen a 1 (Tropomyosin) from Penaeus aztecus.

Pen a 1, the major shrimp allergen from the brown shrimp Penaeus aztecus was purified by preparative SDS-PAGE. Peptides were generated from Pen a 1 by CNBr cleavage and endoproteinase (Lys-C, Glu-C, trypsin, alkaline protease, Arg-C, chymotrypsin) digestion. The molecular weights of the resulting CNBr cleavage and enzymatic digestion products, separated by peptide SDS-PAGE, ranged from 1.5 to 20 kD. Following SDS-PAGE and semidry blotting, the analysis of monoclonal antibody (mAb) and subjects' IgE reactivities demonstrated that with the exception of alkaline protease, all cleavage procedures yielded IgE-binding peptides. However, since not all peptides of every digest bind IgE, it appears that IgE-binding epitopes are restricted to certain parts of the Pen a 1 molecule. mAbs bound to CNBr, Lys-C, trypsin, Glu-C and Arg-C peptides. Since mAbs reacted to several peptides from the same digest, Pen a 1 may have several similar epitopes. The comparison of IgE and mAb reactivities demonstrated similar but not identical binding patterns.

Allergens↗
PubMedDate not supplied

Characterization of recombinant shrimp allergen Pen a 1 (tropomyosin).

Tropomyosin (Pen a 1) from brown shrimp, Penaeus aztecus, has been identified as the only major shrimp allergen. Since beef, pork and chicken are other tropomyosin-containing foods that are not very allergenic, tropomyosins can serve to investigate the contribution of the structural properties of a protein to its allergenicity. The aim of this study was to determine the primary structure of Pen a 1 and to identify IgE-binding epitopes. The screening of a unidirectional expression cDNA library from shrimp tail muscle with the Pen-a-1-specific monoclonal antibody 4.9.5 resulted in 4 positive Escherichia coli clones. Immunoblot analysis with human sera from shrimp-allergic subjects demonstrated IgE binding of all 4 recombinant shrimp proteins. Three of 4 expressed recombinant proteins have a molecular weight of approximately 36 kD, consistent with the molecular weight of natural Pen a 1. The DNA sequence analysis identified these recombinant shrimp proteins as tropomyosin and could be aligned with the sequence of greasyback shrimp (Metapenaeus ensis) tropomyosin (Met e 1). In order to characterize contiguous IgE-binding epitopes of Pen a 1, a peptide library (Novagen epitope mapping system) expressing 10-30 amino-acid-residue-long recombinant Pen a 1 peptides was constructed and screened with human IgE. Four recombinant, IgE-reactive Pen a 1 peptides were selected and sequenced. They show various degrees of sequence identity with tropomyosins of other arthropods, such as fruitfly and house dust mite, helminths and vertebrates.

Allergens↗