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Biomedical subjects

A Ben-Yehuda

Publications and source records attributed to A Ben-Yehuda.

At least 37 records · Page 2Linked to original sources

Scavenger receptor activity and expression of apolipoprotein E mRNA in monocyte-derived macrophages of young and old healthy men.

The aim of this study was to compare some aspects of lipid metabolism in monocyte-derived macrophages isolated from young males, aged 18-24 years, and old males, aged 74-90 years, who were found healthy in accordance with the Senieur protocol. The parameters tested were metabolism of 125I-acetylated low-density lipoproteins (LDL) and oxidized LDL, incorporation of [3H]cholesterol into cholesteryl ester and expression of apolipoprotein E (apo E) mRNA. Cell association and degradation of 125I-acetylated LDL by macrophages of old and young subjects, respectively, was 15,978 +/- 2492 and 9300 +/- 1416 ng/mg cell protein per 24 h. Incorporation of [3H]cholesterol into cellular [3H]cholesteryl ester in the presence of acetylated LDL in cells isolated from old subjects was twice that in cells from young subjects. The macrophages from both age groups metabolized less 125I-oxidized LDL than 125I-acetylated LDL. Cell association and degradation of 125I-oxidized LDL in cells from old and young subjects, respectively, was 6779 +/- 1398 and 3219 +/- 643 ng/mg cell protein per 24 h. Expression of apo E mRNA was determined by reverse transcriptase polymerase chain reaction. In the basal state, it was 5.8 +/- 0.4 and 2.4 +/- 0.2 photo-stimulated luminescence (PSL) units in cells from the old and young subjects, respectively, and increased after exposure to acetylated LDL. In conclusion, these findings suggest that a combination of higher scavenger receptor activity and increased expression of apo E mRNA in macrophages could contribute to (a) enhanced metabolism of modified LDL and (b) more efficient removal of cholesterol from arteries, thus leading to healthy old age.

Acetylation↗

The syndrome of inappropriate antidiuretic hormone secretion in the elderly.

OBJECTIVE: To determine clinical characteristics of elderly patients presenting with the syndrome of inappropriate antidiuretic hormone secretion (SIADH), their outcome, and the extent of evaluation that is warranted. DESIGN: A retrospective study. SETTING: An 800-bed primary and tertiary care center in Jerusalem, Israel. PATIENTS: Fifty elderly patients, hospitalized with serum sodium levels below 130 mmol/L consistent with a diagnosis of SIADH. MEASUREMENTS: Data collection of the medical history, functional status, physical examination, laboratory evaluation, length of hospital stay, treatment, and outcome. RESULTS: The neurological clinical presentation on admission ranged widely: 48% were fully alert, 42% were stuporotic, and 10% had seizures. Sensorial impairment was significantly associated only with sodium values of less than 110 mmol/L. The majority of patients underwent a comprehensive work-up including chest x-ray, computerized tomography (CT) scans, and thyroid and adrenal function tests. The cause of SIADH in most of the patients remained obscure (60% of cases were idiopathic). The 2 main causes identified were pneumonia in 9 cases (18%) and medication in 6 cases (12%). Most of the patients survived the event; only two patients died, both because of sepsis and not due to hyponatremia. The average hospital stay was 12.8 +/- 9 days. CONCLUSIONS: Elderly patients with SIADH usually have an idiopathic form of this condition and a benign course. Extensive routine diagnostic procedures are not warranted. Simple measures like medical history taking with special emphasis on medications, physical examination, and chest x-rays can lead to a treatable diagnosis in most patients who do not have the idiopathic form of SIADH.

Aged↗

Legionella feeleii pneumonia and pericarditis.

Legionella feeleii pneumonia has been described in seven cases, three of them being immunocompromised. We describe a case of L. feeleii pneumonia and pericarditis in a healthy man. Epidemiological survey was not conclusive. To the best of our knowledge, there have been no previous descriptions of pericarditis caused by this organism.

Humans↗

Interleukin-7-enhanced cytotoxic T lymphocyte activity after viral infection in marrow transplanted mice.

Lethally irradiated BALB/c mice were reconstituted by syngeneic bone marrow transplantation (BMT), and injected with recombinant interleukin 7 (rIL-7), recombinant interleukin 2 (rIL-2), or saline 10 days post-transplantation. Intranasal infection with A/PR8/34 influenza virus 2 weeks after BMT was associated with the highest survival rate in the rIL-7 treated group. The protective mechanism elicited by rIL-7, as manifested by very low virus titers in the lung, involves T and B cell functions. High hemagglutinin inhibition antibody levels were observed on days 7 and 12 post-challenge in the rIL-7 mice. Moreover, the anti-influenza cytotoxic T lymphocyte activity was induced primarily by rIL-7, leaving the effect of rIL-2 on the same level as that of the control. Thus, rIL-7 promotes both T cell-mediated function and B cell production during the immunodeficient state after BMT. This cytokine may prove a potential immunotherapeutic modality in BMT recipients.

Animals↗

Dehydroepiandrosterone treatment is not beneficial to the immune response to influenza in elderly subjects.

BACKGROUND: Dehydroepiandrosterone (DHEA) is a native steroid with an immunomodulating activity that was suggested to counter-regulate some phenomena of immunosenescence. Recently, it was shown to reverse the age-associated decline of immune response against influenza vaccine in aged mice. The present study was designed to evaluate the effect of DHEA on the immunization of elderly volunteers against influenza. METHODS: Seventy-one elderly volunteers age 61-89 yr were enrolled in a prospective randomized, double-blind study to receive either DHEA (50 mg qd p.o. for four consecutive days starting two days before immunization) or placebo. Antibody response to the vaccine was measured before and 28 days after vaccination. RESULTS: DHEA treatment significantly increased serum DHEA-sulfate (DHEA-S). No enhancement in established immunity was observed. A significant decrease in attainment of protective antibody titer (1:40 or higher) against the A/Texas strain in subjects with nonprotective baseline antibody titer was recorded following DHEA treatment compared with placebo (52% vs. 84%, P < 0.05). Baseline DHEA-S serum levels were inversely related to attainment of immunization in DHEA-treated subjects. Influenza-like morbidity during the winter was low in the study group with no difference between the DHEA and placebo groups. CONCLUSIONS: Although highly effective in aged rodents, a short course of DHEA treatment did not improve the age-related declined response to immunization against influenza in human subjects. Higher baseline DHEA-S levels are not predictive of better immunization against influenza in the elderly.

Aged↗

Primary non-Hodgkin's lymphoma of the lung presenting as bronchiolitis obliterans organizing pneumonia.

A 44-year-old man presented with fever, dyspnea, and bilateral cavitary lung lesions. Following percutaneous transthoracic CT guided needle biopsy of the lung, a diagnosis of bronchiolitis obliterans organizing pneumonia (BOOP) was made and the patient was treated with corticosteroids. Despite a good initial response he developed new lung lesions within six months, associated with a lack of response to corticosteroids. Due to further deterioration and the development of Guillian-Barre' syndrome an open lung biopsy was performed and revealed T-cell rich, B-cell non Hodgkin's lymphoma with BOOP. We suggest that BOOP may be the presenting manifestation of primary lung lymphoma. We recommend that when BOOP has an atypical course or does not respond to corticosteroids open lung biopsy should be performed in order to exclude pulmonary lymphoma.

Adult↗

Salmonella infection and pneumonia in a patient with kyphoscoliosis.

Pulmonary involvement is an uncommon extraintestinal manifestation of salmonellosis. We describe a 30 year old man with mental retardation, presenting with salmonella gastroenteritis and bacteremia. An early pneumonia evolving in the clinical setting of severe kyphoscoliosis, suggests that hematogenous spread to the lungs may occur as a result of abnormalities of the chest wall.

Adult↗

Metformin-induced lactic acidosis associated with acute renal failure.

A 69-year-old diabetic woman with diffuse atherosclerosis presented with acute renal failure due to contrast nephropathy and severe metformin-induced lactic acidosis. There was a discrepancy between the patient's elevated serum creatinine level, indicative of severe renal insufficiency, and her very low blood urea nitrogen content. It is postulated that the patient's extremely severe acidosis interfered with her hepatic urea generation, contributing to this unusual biochemical abnormality.

Acidosis, Lactic↗

Lymph node cell vaccination against the lupus syndrome of MRL/lpr/lpr mice.

Immunization with pathogenic lymphoid cells has been shown to induce resistance to disease in experimental animal models of cell mediated autoimmunity. In the present work we tested the effectiveness of this approach in a spontaneous murine autoimmune disease, the MRL/lpr/lpr (MRL/1) murine lupus model. We now report that the anti-DNA antibodies and glomerulonephritis of MRL/1 mice could be prevented by the adoptive transfer of spleen cells from MRL/+ mice that had been vaccinated with MRL/1 lymph node T lymphocytes, but not by direct vaccination of MRL/1 mice with their cells. These results indicate that the lupus of MRL/1 mice is susceptible to regulation by adoptive vaccination and that these autoimmune mice lack the ability to raise a suppressive response against their own pathogenic cells.

Adoptive Transfer↗

Stimulation of immune reconstitution by interleukin-7 after syngeneic bone marrow transplantation in mice.

Successful outcome of autologous bone marrow transplantation (BMT) is severely handicapped by susceptibility to infection and by a high rate of relapse. While quantitative aspects of the immune system generally return to normal within the first 3-4 months after BMT, the recovery of qualitative immune functions is prolonged. Since interleukin-7 (IL-7) has growth-promoting and differentiating effects on pre-B cells and immature thymocytes, its role in the recovery of immune functions was investigated in BALB/c mice after syngeneic BMT (sBMT). After sBMT, mice treated with human recombinant IL-7 (rIL-7) showed an 11.9-fold increase in thymic cellularity associated with an enhanced response to a mitogenic stimulus compared with the controls. rIL-7 significantly increased RAG-1 expression and promoted V beta 8(D)J gene rearrangement of the T cell receptor in the thymus. Further, the cytokine boosted survival after challenge with influenza virus following sBMT. The finding that rIL-7 induces differentiation and proliferation of immature thymocytes and counteracts post-BMT immune deficiency makes it a promising medium for clinical application in BMT patients.

Animals↗

Dehydroepiandrosterone enhances influenza immunization in aged mice.

The effect of DHEA administration on the age-associated decline in immunity against influenza vaccine was studied. Increased humoral response was observed in 16- and 24-month-old mice immunized by live A/PR/8/34 (H1N1) influenza virus following DHEA treatment (a single injection adjacent to immunization). Furthermore, DHEA-treated mice demonstrated increased resistance to postvaccination intranasal challenge with live influenza virus. Thus, DHEA treatment overcomes the age-related defect in the immunity of old mice against influenza.

Aging↗

Effect of transforming growth factor-beta on lipoprotein lipase in rat mesenchymal heart cell cultures.

The effect of recombinant transforming growth factor-beta 2 (rTGF-beta 2) on lipoprotein lipase (LPL) synthesis was studied in mesenchymal rat heart cell cultures. Addition of rTGF-beta 2 to culture medium containing 20% serum resulted in a time-dependent decrease in LPL activity. With 10 ng/ml a 30% fall occurred after 12 h and only 20% of enzyme activity remained after 24 h with 5 or 10 ng/ml. The minimal effective dose of rTGF-beta 2 was 0.1 ng/ml and a 20% decrease occurred after exposure for 24 h. Antibodies specific to TGF-beta 2 blocked this effect. The decrease in enzymic activity was accompanied by a decrease in enzyme mass and LPL mRNA. Addition of rTGF-beta 2 was effective only during the first week in culture, when enzyme activity was increasing but not after 12 days when the cultures were overconfluent, and the enzyme activity was high.

Animals↗

The urine of SLE patients contains antibodies that bind to the laminin component of the extracellular matrix.

Direct immunofluorescence of tissues derived from patients affected with SLE demonstrates antibodies bound to the extracellular matrix (ECM). In the present work we have tested whether such antibodies are found in the serum and urine of lupus patients and mice. We found that the urine of patients with active SLE and of MRL/lpr/lpr mice contains antibodies that bind ECM and that a major target for these antibodies is the 200 kDa light chain of laminin which is one of the matrix components. The level of the anti-ECM, anti-laminin antibodies correlates with disease activity.

Albuminuria↗