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Biomedical subjects

J Hofbauer

Publications and source records attributed to J Hofbauer.

At least 55 records · Page 3Linked to original sources
PubMed1990

Expression of the C3d/EBV receptor and of other cell membrane surface markers is altered upon HIV-1 infection of myeloid, T, and B cells.

Human cell lines (the T-cell lines H9, Jurkat, and HUT102, the myeloid lines U937 and HL60, and the Raji B cell line) were infected with HIV-1. HIV-1 antigen could be detected by immunofluorescence analysis in more than 50% of T cells and myeloid cells 15 days after infection. Infection of Raji cells took more than 2-3 months. Studies of cell surface marker expression revealed remarkable changes after HIV-1 infection of Raji cells: expression of CR2 (C3d/EBV receptor, CD19, CD20, CD22, CD23, CD10, and surface IgM) were highly reduced, in the case of CR2 and membrane-IgM from 100 to 0%, whereas levels of CD37 and CD38 remained unaltered by HIV-1 infection. U937 cells showed a reduction of CD4 expression from 14 to 5% after HIV-1 infection; the CR3 expression slightly increased from 25 to 30%. In contrast, HLA-DR was only expressed (21%) after HIV-1 infection but not in uninfected U937 cells. Expression of HLA-DR could be detected also in HL60 cells (33%) after HIV-1 infection. In H9 cells, CD4 was reduced from 60 to 30% after HIV-1 infection, whereas HLA-DR and CD25/IL-2 receptor expression increased from 16 to 90% and from 0 to 50%, respectively. CD4 was reduced from 70 to 0% from Jurkat cells after HIV-1 infection, whereas expression of CR2 was only slightly diminished from 8 to 4%. Expression of CR1 and HLA-DR was slightly increased in these cells (1 to 3%).(ABSTRACT TRUNCATED AT 250 WORDS)

Antigens, Differentiation, B-Lymphocyte↗
PubMed1990

[The value of physical therapy in genuine female stress incontinence].

In a prospective randomized study the efficiacy of physical therapy in female stress incontinence could be verified. The greatest success rate was achieved by medical gymnastics, whereas the perineal electrical stimulation should be used as supporting measure like a biofeedback mechanism because of its low effective intensity. Despite of the good therapeutic success (51.5%) with lasting effects no objective criteria to the use of physical therapy in female stress incontinence were found.

Adult↗
PubMed1990

E. coli antibodies do not cause false-positivity in recombinant anti-HIV assays.

129 sera with known antibody titres against E. coli 026 and E. coli 055 strains were tested with the Abbot second generation anti-HTLV III recombinant screening assay. No difference in the O.D. values was found between sera with high, normal and low anti-E. coli titres. In addition, no false-positive reactions were observed with the anti-HIV negative sera containing E. coli antibodies in high titres in a Western blot assay in which recombinant env antigen was applied. These results suggest that E. coli assays in which E. coli-produced recombinant antigens are used.

Antibodies, Bacterial↗
PubMed1989

Retroviral infections (HIV-1, HIV-2, and HTLV-I) in rural northwestern Tanzania. Clinical findings, epidemiology, and association with infections common in Africa.

During a three-week period in March/April 1987, the authors examined 253 consecutive patients referred to a rural hospital in northwestern Tanzania. Sera were tested for antibodies to human immunodeficiency virus type 1 (HIV-1), human immunodeficiency virus type 2 (HIV-2), and human T-lymphotropic virus type I (HTLV-I), as well as for various parasites, hepatitis B virus, and Treponema pallidum. Neopterin (urinary and serum) was chosen as the immunologic parameter. In eight of the 253 patients (3.2%), a clinical diagnosis of acquired immunodeficiency syndrome (AIDS) was established. Three of the AIDS patients had HIV-1 antibodies, two had HIV-1 antigen, one had both HIV-1 and HIV-2 antibodies, and in one patient, only HIV-2 antibodies were found. The total HIV-1 and HIV-2 seroprevalence (antibodies plus antigen) was 4.3%; HTLV-I seroprevalence was 9.9%. No correlation could be found between HIV (or HTLV-I) seropositivity and raised levels of antibody to the above pathogens. There was, however, a significantly positive correlation between HIV seropositivity and history of gonorrhea, whereas a history of operations, injections, vaccinations, blood transfusions, or scarification did not influence the level of HIV seropositivity. The most frequently noted epidemiologic association with HIV seropositivity was traveling to or coming from Uganda or Rwanda. Two thirds of the studied Tanzanians had elevated neopterin levels, and all seven HIV-seropositive patients with clinical signs of AIDS had extremely high serum and urinary neopterin levels compared with HIV-seropositive patients without signs of AIDS. Increased neopterin levels reflect a stimulation of the T-cell/macrophage system.

Acquired Immunodeficiency Syndrome↗
PubMed1989

Effect of D-penicillamine on the expression and propagation of the human immunodeficiency virus by H9 T-lymphoblastoid cells.

The effect of D-penicillamine on the replication of the Human Immunodeficiency Virus (HIV) in H9 T-lymphoblastoid cells was evaluated. HIV-infected and uninfected H9 cells were incubated for a period of 6 weeks with various concentrations of D-penicillamine. During the first 8 days, D-penicillamine (at concentrations of 0-150 micrograms/ml) did not influence growth and viability of H9/H9-IIIB cells. However, long term cultures and higher doses of the drug caused a decay in cell number and viability of the cultured cells. Up to the 8th day of culture, D-penicillamine did not exert an inhibiting effect on the number of HIV-infected cells but did suppress HIV-antigen production by up to 29%. After 6 weeks, in addition to a decrease of the relative viral antigen concentration from 390-500 ng/ml in the medium control to 210-320 ng/ml in cultures containing 150 micrograms D-penicillamine/ml, D-penicillamine also reduced the percentage of HIV-positive cells. Thus our results demonstrate an antiviral effect of D-penicillamine in H9 cultures.

Cells, Cultured↗
PubMed1988

Impact of allopurinol treatment on the prevention of hyperuricosuric calcium oxalate lithiasis.

The beneficial effect of allopurinol treatment in metaphylaxis of hyperuricosuric calcium oxalate lithiasis has been analyzed in a retrospective study covering 10 years. 83 patients with hyperuricosuric calcium oxalate lithiasis (48 recurrent stone formers, 35 patients with a single stone episode) were treated with 300 mg allopurinol for 33.1 +/- 11.5 months. Subsequently, each patient was controlled for 43.9 +/- 27 months without therapy. The overall relapse rate was 28.9% but there is no statistically significant difference between treatment with and without allopurinol (Mann-Whitney: p = 0.16). The only striking difference was the fact that, with one exception, stone relapses occurred only in the group of recurrent stone formers, whereas the group with single stone formation seemed to be at a clearly decreased risk for stone recurrence during follow-up. This would suggest that factors other than those investigated in this study are responsible for the phenomenon of recurrent stone formation.

Allopurinol↗
PubMed1987

Coexistence for systems governed by difference equations of Lotka-Volterra type.

The question of the long term survival of species in models governed by Lotka-Volterra difference equations is considered. The criterion used is the biologically realistic one of permanence, that is populations with all initial values positive must eventually all become greater than some fixed positive number. We show that in spite of the complex dynamics associated even with the simplest of such systems, it is possible to obtain readily applicable criteria for permanence in a wide range of cases.

Animals↗
PubMed1987

The "battle of the sexes": a genetic model with limit cycle behavior.

A two-locus genetic model, based on Dawkins "sex war" game, with the fitness of the genotypes at each locus depending on the gene frequencies at the other, is shown to give rise to a stable limit cycle. The mathematical analysis involves averaging techniques and elliptic integrals.

Animals↗
PubMed1986

Neopterin as tumour marker serum and urinary neopterin concentrations in malignant diseases.

Serum and urinary neopterin concentrations were measured in 142 patients suffering from various malignant diseases. Increased serum and urinary neopterin levels were found in 48% and 55% of patients respectively. Neopterin showed sufficient sensitivity in the detection of haematological disorders and hypernephroma, whereas the sensitivity of neopterin was rather poor in patients with other solid tumours. Comparison of serum alpha-fetoprotein (AFP) and human chorionic gonadotropin (HCG) concentrations and serum or urinary neopterin levels in testicular cancer patients showed that determination of neopterin provides no further information in the management of these patients. In testicular cancer patients receiving adjuvant chemotherapy, a significant increase in serum (p less than 0.005) and urinary (p less than 0.0005) neopterin concentrations was measured after chemotherapy, reflecting the release of neopterin from macrophages during the damage by cytotoxic drugs. In the adjuvant testicular tumour patients, known to be tumour free, 1 out of 16 patients showed elevated serum and 3 out of 15 patients showed false positive urinary neopterin levels. False positive serum (24%) and urinary (37%) neopterin values were also obtained in 28 patients with various nonmalignant diseases, but no evidence for an inflammatory process. In 23 patients with inflammatory diseases pathological serum and urinary neopterin levels were measured in 55% and 59% respectively. When a RIA was compared with a HPLC method, higher urinary neopterin values were obtained with the RIA, indicating that non-oxidized pterines are also determined by the RIA method. In conclusion, neopterin might be a helpful biological marker in monitoring patients with malignant haematological disorders and renal cell carcinoma, but provides no additional information in other solid tumours studied.

Adolescent↗
PubMed1986

[Urologic complications following curative radiotherapy of gynecologic cancers].

Seventy-nine patients with urological complications after radiotherapy of their gynecological carcinomas are presented. Twenty-eight patients underwent operation before irradiation. The time between radiotherapy and occurrence of urological complications varied from 0.5 to 27 years (mean 5.3 years). One third of the patients showed a combination of at least two side effects of radiotherapy. There were good results of infiltration therapy with orgotein in patients with radiation cystitis. Because of the unsatisfactory result from primary operation of fistulas, suprapubic urinary diversion is preferred. Gynecologic operation prior to radiotherapy did not influence the results of urological treatment. Seven patients (8.8%) died from urological complications or from complications after urologic treatment. 6 patients (7.6%) showed cancer of the radiated region (3 bladder cancers, 3 colon cancers) within 6 to 20 years after radiotherapy.

Combined Modality Therapy↗
PubMed1985

The selection mutation equation.

Fisher's Fundamental Theorem of Natural Selection is extended to the selection mutation model with mutation rates epsilon ij = epsilon i, i.e. depending only on the target gene, by constructing a simple Lyapunov function. For other mutation rates stable limit cycles are possible.

Gene Frequency↗
PubMed1984

[Value of sonography, computed tomography and angiography in adrenal diagnosis].

Between 1979 and 1982, 47 patients with pathological process of the adrenals were surgically treated after preceding thorough non-evasive angiographic diagnosis (6 phaeochromocytomas, 20 adrenal adenomas, 8 adrenal hyperplasias, 5 adrenal carcinomas, 5 adrenal cysts and 3 adrenal metastases). The most consistently accurate results were obtained via adrenal phlebography with an accuracy of 94%. This was followed by non-evasive computed tomography (87%). Compared with the data given in literature, hormone determination in the adrenal venous blood was less favourable (79%). Selective adrenal arteriography, which was used less often, yielded correct results in 83% of the cases, whereas the number of accurate diagnoses achieved via sonography was lowest with 54%.

Adenoma↗
PubMed1981

Familial Nevus of Ota.

A white family with three generations (one by history) showing the clinical picture of nevus of Ota is presented. In the two generations examined, no evidence of uveal malignant melanoma was found. This is the first such family reported in the English literature and the fifth family in the world literature. It shows the importance of a good family history in dealing with a patient with a nevus of Ota. Affected family members should be examined carefully to rule out uveal malignant melanoma until the questions surrounding its reported association with nevus of Ota can be resolved.

Aged↗
PubMed1978

Orbital extension of retinoblastoma: a clinicopathological study.

We have studied all cases of orbital extension of retinoblastomas at the Edward S. Harkness Eye Institute in New York since 1925. Only 9.4% of the patients lived more than 2 years after diagnosis. Orbital retinoblastoma is frequently associated with systemic metastases. We emphasize the significance of massive choroidal involvement and periemissarial extension. Careful handling of the enucleation specimen at the time of surgery and during histologic preparation is important to avoid cell spillage and artifacts. Treatment should be early, multidisciplinary and include adjuvant chemotherapy.

Child↗
PubMed1976

Invasion of the optic nerve by retinoblastoma: a clinicopathological study.

We have studied all cases of optic nerve invasion in retinoblastoma seen at the Edward S. Harkness Eye Institute in New York since 1925. Since 1959 optic nerve invasion has been less extensive--suggesting earlier diagnosis and management. Since 1959 there has also been an increase in the number surviving. Survival correlates with the extent of spread to optic nerve, choroid and extrabulbar tissues. Current and future therapy are discussed. The importance of subpial extension of retinoblastoma is noted and its relationship to the mode of therapy is emphasized.

Child↗