Search PubMedSearch

Biomedical subjects

D Robbins

Publications and source records attributed to D Robbins.

At least 19 recordsLinked to original sources

Allotype-dependent stimulation of peripheral blood and synovial lymphocytes by IgG3 in rheumatoid arthritis.

The immunopathologic process of rheumatoid arthritis (RA) is primarily expressed in the synovium where rheumatoid factor (RF) synthesis is concentrated. We hypothesized that RF synthesized by rheumatoid synovial cells (RSC) may be driven via a T cell-mediated immune response developed against IgG3 epitopes. To identify and characterize specific RSC RF epitopes and T cell antigens, two 28 amino acid peptides homologous with the C-terminus of IgG1 (P1) and IgG3 [G3m(5)] (P3) were synthesized and used in RF-binding studies and lymphocyte proliferation assays. Our results indicate that (i) the C-terminus of the CH3 domain contains epitopes for IgG3-reactive RSC RF; (ii) IgG3-reactive RSC RF binds primarily to IgG3 [G3m(5)]; (iii) P3 stimulated proliferation of T lymphocytes from both RA peripheral blood and RSC; and (iv) RF production was enhanced by P3 in selected RA cell cultures. These observations suggest that the C-terminus of IgG3 allotype G3m(5) may be important in T cell activation and RF production in RA.

Amino Acid Sequence

Prenatal detection and management of quadruple nuchal cord. A case report.

As imaging techniques improve, nuchal cords are often being identified prior to labor. Nuchal cords are encountered in up to 25% of deliveries and are usually not clinically significant. They may, however, have devastating results. Nuchal cords may be associated with abnormal fetal activity and testing, but there is often no clinical warning of a nuchal cord during pregnancy, labor or delivery. We report a case of a quadruple nuchal cord discovered after the mother complained of decreased fetal movement. The clinical course of this patient highlights many of the difficulties encountered in the management of antenatally diagnosed nuchal cords, particularly in the preterm fetus.

Acidosis

Home visits for pregnant diabetic women: environmental assessment as a basis for nursing intervention.

A major goal in management of pregnancies complicated with diabetes is strict control of blood glucose levels. After glucose control is achieved, home visits by the Perinatal Clinical Nurse Specialist (PCNS) who has advanced knowledge and skills in the management of high risk pregnancies can be invaluable. The PCNS systematically assesses the client's environment and its effects upon the client's ability to carry out the many therapeutic self-care demands associated with the diabetic pregnancy. These include the client's ability to: identify and act upon episodes of hypo- or hyperglycemia, monitor blood glucose levels, self-administer insulin, self-monitor fetal activity, and identify and act upon danger signs in pregnancy and signs of labor. The PCNS, by assessing and planning within the framework of the client's environment, facilitates continued control of diabetes as the woman makes the transition from the hospital to the home and/or work environment.

Female

An immunological study in patients with seborrhoeic dermatitis.

The humoral and cellular immune-status was studied in 30 patients with seborrhoeic dermatitis. Increased frequencies of natural killer cells were found in 46% of patients. Furthermore, subnormal mitogen stimulation responses were demonstrated in 13 patients, whereas two individuals were found to have very high numbers of activated T lymphocytes in peripheral blood. Higher-than-normal total serum IgG and IgA was observed in 14 and 11 patients, respectively. For nine of 12 patients with skin lesions, dermal perivascular cell infiltrates were seen. The majority of the infiltrating cells reacted with anti-CD4 antibodies. HLA-DR-expressing keratinocytes were found in two biopsies. The study suggests that patients with seborrhoeic dermatitis may have depressed T-cell function. This could have a bearing on their susceptibility to the Pityrosporum ovale-associated dermatitis. The very high frequencies of activated T cells observed in the peripheral blood of two otherwise healthy seborrhoeic individuals suggests that intermittent systemic immune activation may occur. Seborrhoeic dermatitis is a common skin disease. It can be diagnosed by its characteristic red to yellow-brown lesions covered with greasy scales distributed in areas with a high number of sebaceous glands, such as the scalp, face and upper trunk. There is an association between seborrhoeic dermatitis and the lipophilic yeast Pityrosporum ovale but its exact aetiological role is not known. The yeast is a member of the normal cutaneous flora but also the aetiological agent of pityriasis versicolor and Pityrosporum folliculitis. P. ovale can activate complement via the direct and alternative pathways. This may play some part in the induction of inflammation.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult

The evaluation of various methods and antigens for the detection of antibodies against Pityrosporum ovale in patients with seborrhoeic dermatitis.

Sera from 10 patients with seborrhoeic dermatitis and from 10 age-matched healthy individuals were examined for IgG activity against Pityrosporum ovale. The IgG activity was analysed using the following techniques: an enzyme-linked immunosorbent assay (ELISA) against whole P. ovale cells, purified cell-wall carbohydrate or protein extract, an indirect slide-immunofluorescence assay and fluorescence-activated flow cytometry using the whole organism as antigen. The ELISA method using the protein antigen was the only technique that showed a significant difference between patients and controls; a lower antibody response was found in the seborrhoeic dermatitis patients compared to healthy controls.

Adult

Opinions on treatment of women with habitual abortion based on investigations for blocking antibody and autoantibodies.

Three hundred and thirty-seven women with habitual abortion of unknown etiology were studied for cellular reactivity and blocking antibody in one-way mixed lymphocyte culture. Their sera were investigated for anti-cardiolipin antibodies, antinuclear antibodies, and antibodies against DNA, and the activated partial thromboplastin time (APTT) and complement levels of their plasma were determined. Increased anti-cardiolipin antibody levels were demonstrated in 77 (22%) of the 337 women, all of whom were considered healthy and had no signs of autoimmune disease. Most patients with high anti-cardiolipin antibody levels displayed lowered values of complement factor C4. According to our experiences, the mere occurrence of anti-cardiolipin antibody in women with habitual abortion is no absolute cause for treatment with prednisolone, not even in cases with greatly elevated anti-cardiolipin values. Therapy with prednisolone and acethylsalicylic acid (ASA) during pregnancy should be given to those women who have high levels of anti-cardiolipin antibodies concomitant with high APTT values, low values of complement C4, and strong blocking antibody. Anti-cardiolipin antibody has been investigated during pregnancy in 136 normal pregnant women, 11 of whom (8%) were positive at any sampling occasion, but only one of whom (1%) had high levels. Evidently the development of anti-cardiolipin antibody is no normal feature of pregnancy among Swedish women and thus the high frequency found among healthy Swedish women with habitual abortion remains unexplained. We have introduced an immunization program of leukocyte transfusions in habitual abortion. The development of previously absent blocking antibody seems to be a valuable prognostic sign of possible success for immunization therapy against habitual abortion.

Abortion, Habitual

Proteus mirabilis flagella and MR/P fimbriae: isolation, purification, N-terminal analysis, and serum antibody response following experimental urinary tract infection.

Urinary tract infection with Proteus mirabilis may lead to serious complications, including cystitis, acute pyelonephritis, fever, bacteremia, and death. In addition to the production of hemolysin and the enzyme urease, fimbriae and flagellum-mediated motility have been postulated as virulence factors for this species. We purified mannose-resistant/proteuslike (MR/P) fimbriae and flagella from strains CFT322 and HU2450, respectively. Electron microscopy revealed highly concentrated preparations of fimbriae and flagella. Fimbrial and flagellar structural subunits were estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis to be 18.5 and 41 kDa, respectively. N-terminal sequencing revealed that 10 of the first 20 amino acids of the major MR/P subunit matched the sequence of the P. mirabilis uroepithelial cell adhesin N terminus and 11 of 20 amino acids matched the predicted amino acid sequence of the Escherichia coli P fimbriae structural subunit, PapA. In addition, 90 and 80% homologies were found between the first 20 amino acids of P. mirabilis flagellin and those of Salmonella typhimurium phase-1 flagellin and the E. coli hag gene product, respectively. An enzyme-linked immunosorbent assay using purified antigens showed a strong reaction between the MR/P fimbriae or flagella and sera of CBA mice challenged transurethrally with P. mirabilis. A possible role for MR/P fimbriae in the pathogenesis of urinary tract infection is supported by (i) a strong immune response to the antigen in experimentally infected animals, (ii) amino acid sequence similarity to other enteric surface structure, and (iii) our previously reported observation that MR/P fimbriae are expressed preferentially as the sole fimbrial type in human pyelonephritis isolates.

Amino Acid Sequence

Coexistent Felty's syndrome and palindromic rheumatism.

Palindromic rheumatism is a syndrome of intermittent abrupt onset monoarthritis with asymptomatic intercritical periods of variable duration, which commonly evolves into rheumatoid arthritis. Felty's syndrome consists of leucopenia (selective neutropenia) and splenomegaly, usually occurring in longstanding classic rheumatoid arthritis. Felty's syndrome can be confused with the more recently recognised rheumatoid arthritis associated large granular lymphocyte proliferative disease. This paper describes a patient with palindromic rheumatism presenting with Felty's syndrome in whom large granular lymphocyte proliferative disease was ruled out by lymphocyte phenotyping.

Cell Count

Mesangial glomerulopathy and IgM rheumatoid factor in rheumatoid arthritis.

Hematuria and proteinuria in rheumatoid arthritis (RA) are commonly associated with drug therapy but occur independently of drugs, amyloid or urologic disorders. The latter occurrences suggest a primary renal lesion associated with RA. Review of reported renal biopsies identifies mesangial glomerulopathy as a common finding in RA patients without associated drug therapy and that it is frequently associated with hematuria in nonrheumatoid patients. Moreover, immunoglobulins have been shown to concentrate in the mesangium in experimental animals, suggesting that a functional response by the kidney mesangium to remove IgM rheumatoid factor (RF)-IgG complexes could lead to this mesangial lesion. We describe 3 patients with RA who had a mesangiopathy characterized by increased quantities of mesangial matrix and deposition of IgM without other lesions. Together, these observations suggest that: (1) mesangial glomerulopathy is common in RA; (2) removal of circulating RF-IgG complexes is a function of the mesangium and might produce this renal lesion; (3) mesangial glomerulopathy may be responsible for much of the hematuria observed in RA patients and, in many cases, may not be drug related and thus may not require discontinuing beneficial therapy.

Adult

Misoprostol heals gastroduodenal injury in patients with rheumatoid arthritis receiving aspirin.

High-dose aspirin therapy for rheumatoid arthritis is frequently associated with severe gastrointestinal injury. To explore the possibility of reversing such damage, we conducted a double-blind, multicenter study with misoprostol, a prostaglandin E1 analog, which has demonstrated mucosal protective, gastric antisecretory, and ulcer healing properties. We also studied possible interference of misoprostol with continuing aspirin treatment in the management of patients with rheumatoid arthritis. Patients with confirmed rheumatoid arthritis and endoscopically documented gastroduodenal lesions were randomly assigned to receive 200 micrograms of misoprostol four times a day (123 patients) or placebo (116 patients). Each concurrently received 650 to 1300 mg of aspirin four times a day. After eight weeks of treatment, misoprostol was statistically superior to placebo in healing gastric mucosal injury (70% vs 25%) and duodenal mucosal injury (86% vs 53%). Patients with gastric or duodenal ulcers on admission had superior ulcer healing rates with misoprostol (67% vs 26%). There was no evidence of interference with the antirheumatic properties of aspirin. Mild to moderate adverse experiences were equally noted in misoprostol and placebo groups. Misoprostol, coadministered with aspirin, is well tolerated and highly effective in healing aspirin-associated gastroduodenal lesions in patients with rheumatoid arthritis without altering the therapeutic benefits of aspirin.

Adult

Activated terminal complement in cerebrospinal fluid in Guillain-Barré syndrome and multiple sclerosis.

A quantitative enzyme-linked immunosorbent assay was used to measure the concentration of fluid-phase complement C5b-9 complexes (SC5b-9) in the cerebrospinal fluid (CSF) of 14 patients with acute monophasic Guillain-Barré Syndrome (GBS), 21 patients with multiple sclerosis (MS), and 11 patients with noninflammatory central nervous system (CNS) diseases. SC5b-9 complexes were detected in the CSF of 13 of 14 patients with acute GBS (mean, 3.08 micrograms/ml; range, 0 to 7.1 micrograms/ml) and 16 of 21 patients with MS (mean, 1.83 micrograms/ml; range, 0 to 7.5 micrograms/ml). In the control group of patients with noninflammatory CNS diseases, SC5b-9 was not detected in eight of 11 and was present in low concentrations in the remaining three patients (mean, 0.28 micrograms/ml; range, 0 to 1.7 micrograms/ml). The finding of SC5b-9 complexes in the CSF of patients with GBS and MS suggests that terminal complement components may participate in the tissue-damaging processes in these diseases.

Complement Activation

Comparison of ribosomal entry and acceptor transfer ribonucleic acid binding sites on Escherichia coli 70S ribosomes. Fluorescence energy transfer measurements from Phe-tRNAPhe to the 3' end of 16S ribonucleic acid.

Distances were measured by nonradiative energy transfer from fluorescent probes specifically located on one of three points of yeast or Escherichia coli Phe-tRNAPhe enzymatically bound to the entry site or to the acceptor site of E. coli 70S ribosomes to energy-accepting probes on the 3' end of the 16S ribonucleic acid (RNA) of the 30S subunit. The Y base in the anticodon loop of yeast tRNAPhe was replaced by proflavin. Fluorescein isothiocyanate was attached to the X base (position 47) of E. coli tRNAPhe. E. coli tRNAPhe which had been photochemically cross-linked between positions 8 and 13 followed by chemical reduction to form a fluorescent probe was also used. Labeled tRNAs were aminoacylated and enzymatically bound to the ribosome in the presence of elongation factor Tu and guanosine 5'-triphosphate (acceptor-site binding) or a nonhydrolyzable analogue (entry-site binding). Nonradiative energy transfer measurements were made of the distances between fluorophores located on the Phe-tRNA and the fluorophore at the 3' end of 16S RNA. Calculations were based on comparison of the fluorescence lifetime of the energy donor, located on the Phe-tRNA, in the absence and presence of an energy acceptor on the 3' end of the 16S RNA. Under both sets of binding conditions, the distances to the 3' end of 16S RNA were found to be the following: cross-linked tRNA, greater than 69 A; Y base of tRNA, greater than 61 A. The distance between the 3' end of 16S RNA and the X base of tRNA was found to be 81 A under acceptor-site binding conditions but greater than 86 A under entry-site binding conditions.

Energy Transfer

A cluster of adolescent suicide attempts: is suicide contagious?

Adolescent self-destructive behavior has increased during recent decades. Suicide now ranks third as a cause of death among older teenagers. Although recent studies have highlighted multiple risk factors for this behavior, little attention has been paid to the role of contagion as a possible cause for suicide attempts. Within a 6-month period, a small suburban community experienced two adolescent deaths from suicide followed by five attempts and an admission for suicidal ideation, within 7 weeks subsequent to the second fatality. The six patients were among a group of students from the same high school who not only related to each other during the school day but who also visited each other at the time of hospitalization for suicidal behavior. The possible role of suicidal behavior precipitating other self-destructive attempts within a peer group is explored. The development of strategies for dealing with issues of depression and suicide within a high-school environment may be needed.

Adolescent