PubMed Health⌕ Search

Biomedical subjects

D Keisler

Publications and source records attributed to D Keisler.

14 recordsLinked to original sources
PubMed2001

Antioxidants suppress mortality in the female NZB x NZW F1 mouse model of systemic lupus erythematosus (SLE).

Inflammation produces reactive oxygen intermediates (ROI) that cause vascular damage and activate T lymphocytes. Conversely, antioxidants not only protect tissue from oxidative damage but also suppress immune reactivity. The objective of this study was to examine immunomodulatory effects of the non-enzymatic antioxidants, N-acetylcysteine (NAC) and cysteamine (CYST), on autoimmune disease, glomerulonephritis, and mortality in the female B/W mouse model of human systemic lupus erythematosus (SLE). The development of murine lupus was assessed during the lifespan of female B/W mice given NAC or CYST. Morbidity and mortality were assessed daily. At 6 week intervals mice were examined for weight change, albuminuria, serum BUN, antibodies to DNA, and IgG immunoglobulin levels. Serum prolactin, estrogen and progesterone were measured at 18 weeks of age. In a parallel study, NAC- and CYST-treated and control B/W mice were examined at 24 weeks of age for interval renal histopathology, lymphocyte adhesion molecule expression, and antibody titers and in vitro cytokine production in response to immunization with DNP-KLH. CYST significantly suppressed development of albuminuria and azotemia at 36 and 42 weeks of age compared to control and NAC-treated mice. NAC significantly suppressed anti-DNA antibody levels at 24 weeks. In contrast CYST significantly increased anti-DNA antibody levels at 18 weeks of age (P < 0.001 CYST vs control and NAC-treated mice). Kidneys of CYST-treated mice also had accelerated inflammatory histologic changes despite their lower incidence of albuminuria and azotemia. Mean (+/- s.e.m.) survival of control mice was 33 +/- 2 weeks compared to 38 +/- 2 weeks in NAC-treated mice (P < 0.05 vs control), and 48 +/- 2 weeks in the CYST-treated group (P < 0.01 vs control mice). The antioxidants, NAC and CYST, significantly improved mortality in the female B/W mouse model of SLE. NAC suppressed autoantibody formation and modestly prolonged survival. CYST, despite its augmentation of anti-DNA levels and renal inflammatory changes, inhibited the development of renal insufficiency and markedly improved survival. These findings suggest that ROIs play a role in the pathogenesis of lupus nephritis and that antioxidants reduce the damage causing renal insufficiency. Antioxidants may be a beneficial adjunctive therapy in the treatment of human SLE.

Acetylcysteine↗
PubMed1998

Effects of prolactin in stimulating disease activity in systemic lupus erythematosus.

Systemic lupus erythematosus (SLE), a chronic autoimmune illness, is influenced by hormones. High prolactin concentrations were associated with early death from autoimmune renal disease in NZB/NZW mice, an animal model of severe SLE. NZB/NZW mice that delivered and nursed pups and those that underwent pseudopregnancy had changes in serum IgG and autoantibodies. NZB/NZW mice treated with the prolactin-suppressing drug bromocriptine had prolonged lives. Elevated serum prolactin concentrations are reported in SLE patients of both sexes. We found four women with long-standing hyper-prolactinemia who developed SLE. A survey of premenopausal women whose sera were submitted for autoantibody testing showed that 20% with anti-ds-DNA antibodies also had high prolactin levels. Many hyperprolactinemic patients whose sera were referred to an endocrinology laboratory had positive FANA tests (women 33%, men 53%) but did not have SLE. Disease activity was suppressed in six of seven SLE patients treated with bromocriptine. All had elevated disease activity and five became unexpectedly hyperprolactinemic after treatment stopped. Manipulating serum prolactin affords a means of treating clinical SLE activity.

Bromocriptine↗
PubMed1998

Differential effects of estrogen and prolactin on autoimmune disease in the NZB/NZW F1 mouse model of systemic lupus erythematosus.

Estrogen and prolactin have been shown to modulate autoimmunity in the NZB/NZW F1 (B/W) mouse model of systemic lupus erythematosus (SLE). However, estrogen stimulates prolactin secretion. The goal of this study was to examine differential effects of estrogen and prolactin in the female B/W mouse model of SLE. B/W females were manipulated to create combinations of low and high concentrations of serum estrogen and prolactin. Hyperprolactinemic mice with either low or high serum estrogen levels had accelerated development of albuminuria at 24 and 32 weeks of age compared to normal and hypoprolatinemic mice. High estrogen/high prolactin mice also had a higher percentage of anti-DNA antibodies compared to mice in the low estrogen/low prolactin and the high estrogen/low prolactin groups. IgG levels were not significantly different between groups. Mean survival was shortest in the high estrogen/high prolactin group (34+/-1.0 weeks) and longest in the high estrogen/low prolactin group (42+/-1.2 weeks; P < 0.05). High levels of serum estrogen were associated with depressed in vitro lymphoproliferation and IL-2 production. This study suggests that high prolactin levels in either high or low serum estrogen states are associated with accelerated autoimmunity in the B/W mouse. This study further demonstrates that high estrogen levels do not accelerate murine SLE when the prolactin-stimulating property of estrogen is suppressed by bromocriptine. Further investigation of hormonal interactions in autoimmunity will provide a better understanding of hormonal immunoregulation and, perhaps, lead to improved clinical application of hormonal immunomodulation.

Animals↗
PubMed1998

Bone mineral density and biochemical markers of bone metabolism in ankylosing spondylitis.

OBJECTIVE: To determine (1) bone mineral density (BMD) of the axial and appendicular skeleton in men with moderate and severe ankylosing spondylitis (AS), and (2) associations between BMD and bone metabolism variables. METHODS: Nineteen men with AS and 19 healthy male controls were evaluated for osteoporosis by dual energy x-ray absorptiometry in both the hip and the lateral and posterior-anterior (PA) projections of the lumbar spine. Calcium homeostasis was evaluated by measuring minerals, calcitropic hormones, and markers of remodeling. Total testosterone levels were also measured. RESULTS: Osteopenia was noted in both the hip and spine of the subjects with AS. The lateral projection of L3 was a more sensitive indicator of the vertebral BMD compared to the PA projection. Calciuin homeostasis and testosterone levels were normal in subjects with AS. In most subjects, markers of bone formation and resorption were normal. CONCLUSION: BMD of subjects with AS is decreased, in spite of normal calcium homeostasis and bone remodeling indices.

Adult↗
PubMed1998

Overview of the Diabetes Initiative of South Carolina.

Implementation is underway for many of these programs, and there are descriptions of activities elsewhere in this symposium. The Board recognizes that in dealing with the complications of a chronic disease like diabetes, many years of intense effort will be needed before significant results may be appreciated. Progress will be monitored regularly by the Surveillance Council and SCDCP/DHEC, and modifications of the plan will be made by the Board at intervals after review of the data. We are optimistic that over the next decade, this system will make a significant impact to reduce mortality, morbidity, and costs of diabetes, and the result will be an increased quality of life for people affected by diabetes in South Carolina.

Diabetes Mellitus↗
PubMed1995

Elevated serum prolactin levels in children with juvenile rheumatoid arthritis and antinuclear antibody seropositivity.

OBJECTIVE: To determine if antinuclear antibody seropositivity in girls with juvenile rheumatoid arthritis (JRA) is associated with elevated serum levels of the anterior pituitary hormone prolactin. METHODS: Nineteen premenarchal girls meeting ACR classification criteria for JRA were evaluated for disease activity, antinuclear antibodies (ANA) seropositivity, and serum concentrations of prolactin, estrogen, and thyroid stimulating hormone. RESULTS: The mean serum prolactin concentration of ANA seropositive patients with JRA (10.9 +/- 1.9 micrograms/l) was significantly higher than that for ANA negative patients (5.7 +/- 1.0 micrograms/l; p = 0.043) and an age matched control group (5.8 +/- 1.3 micrograms/l; p = 0.048). CONCLUSION: Children with ANA seropositive JRA have elevated serum levels of the immunostimulatory hormone prolactin.

Antibodies, Antinuclear↗
PubMed1994

Hyperprolactinemia in male NZB/NZW (B/W) F1 mice: accelerated autoimmune disease with normal circulating testosterone.

It has been proposed that the immunostimulatory hormone, prolactin, is associated with flares of systemic lupus erythematosus (SLE). In autoimmune female NZB/NZW F1 (B/W) mice with accelerated lupus-like disease, hyperprolactinemia accelerated autoimmunity. The current study explored effects of moderate and severe hyperprolactinemia in male B/W mice, which have late-onset SLE. Autoimmune disease in B/W males was assessed by measurement of anti-DNA antibodies (anti-DNA), gp70-anti-gp70 immune complexes (gp70IC), IgM, IgG, and renal function. Serum testosterone concentrations were assayed serially. All mice were necropsied when moribund. Hyperprolactinemic B/W males were characterized by premature appearance of anti-DNA and gp70IC and elevation of IgM and IgG. Hyperprolactinemia accelerated mortality with vasculitis and renal disease compared to control mice. Serum testosterone concentrations were not suppressed. In male B/W mice, chronic hyperprolactinemia stimulated autoimmune disease activity; the deleterious effects of prolactin were not mediated through suppression of the immunoprotective hormone, testosterone. This observation supports the proposed association between elevated prolactin levels and exacerbations of SLE.

Animals↗
PubMed1994

Psychological, demographic and situational factors of family physicians which influence cigarette cessation interventions in office-based practice.

Sixty-five office-based family physicians completed a mailed questionnaire which sought to determine the extent to which these physicians offer cigarette cessation interventions to their patients. This information was related to 44 scales from 7 psychological tests completed by each physician during residency training. Ninety percent of these physicians intervene personally, while outside referral to an expert and internal referral to a nurse were each utilized by less than 12% of the sample. Over 45% of these private practitioners used supplemental video or written materials. A number of psychological characteristics but no demographic or situational variables discriminated physicians regarding the implementation of these cigarette cessation interventions.

Adult↗
PubMed1993

Training family physicians: a case study.

A survey of USC/RMH Family Medicine alumni indicated that a large proportion have remained in South Carolina, providing primary care especially in small towns and rural areas. These physicians engage in a broad range of clinical activities and feel comfortable with treating a wide spectrum of patient problems. The alumni are active participants in religious, cultural and civic programs in their communities and they express satisfaction with their decision to practice Family Medicine in South Carolina.

Adult↗
PubMed1993

Effects of parturition, suckling and pseudopregnancy on variables of disease activity in the B/W mouse model of systemic lupus erythematosus.

OBJECTIVE: The pituitary hormone, prolactin, accelerates systemic lupus erythematosus in NZB/NZW F1 (B/W) mice. Our study evaluated disease activity in B/W females experiencing the physiologic hyperprolactinemia of mating, pregnancy, suckling, and pseudopregnancy. METHODS: Nonsuckling postpartum, suckling and pseudopregnant mice were compared to virgin females. Serum prolactin, anti-DNA antibodies (anti-DNA), gp70-anti-gp70 immune complexes, IgM, IgG, albuminuria, and renal function were monitored serially. RESULTS: Females that whelped 2 litters had apparent stimulation of anti-DNA; those that suckled their young had similar premature appearance of anti-DNA as well as delayed, but marked, hypergammaglobulinemia. Pseudopregnant mice, which characteristically secrete repeated surges of prolactin, had significant acceleration of multiple variables of disease activity. CONCLUSIONS: Pregnancy, parturition and suckling did not immediately accelerate lupus in B/W dams, and longevity was not affected in females that had borne litters. Pseudopregnancy was the most effective stimulator of variables of autoimmunity.

Albuminuria↗
PubMed1991

Prolactin influences autoimmune disease activity in the female B/W mouse.

Prolactin, an anterior pituitary hormone, stimulates humoral and cell-mediated immunity. This study investigated effects of manipulating prolactin levels in the autoimmune B/W mouse model of SLE. A group of B/W females was treated with daily injections of the prolactin-suppressing drug, bromocriptine. These mice had delayed elevation of anti-DNA antibodies and serum IgG; longevity was increased compared to control mice. Functioning syngeneic pituitary glands, implanted under the renal capsule, produced prolonged hyperprolactinemia in a separate group of female B/W mice. Hyperprolactinemic animals were characterized by premature albuminuria, elevated circulating gp70IC and IgG, and accelerated mortality. Analyses of thymic and splenic lymphocytes revealed no differences in lymphocyte subpopulations in mice with altered prolactin levels. This is the first report to substantiate an immunomodulatory role for prolactin in B/W mice. Further evaluation of this model may identify specific means of intervening clinically with immunosuppressive hormone-modulating therapy in SLE.

Albuminuria↗
PubMed1991

Effect of injected bovine interferon-alpha I1 on estrous cycle length and pregnancy success in sheep.

In Exp. 1 twice daily i.m. injections of 2 mg recombinant bovine IFN-alpha I1 (rboIFN-alpha I1) (N = 24) or placebo (N = 25) were administered to ewes from Day 12 to Day 16 during a normal oestrous cycle. Treatment did not increase (P greater than 0.10) oestrous cycle length (20.7 +/- 1.2 versus 18.5 +/- 1.4 days). In Exp. 2, ewes were injected twice daily with 2 mg IFN (N = 34) or placebo (N = 36) from Days 11 to 18 after natural mating. The rboIFN-alpha I1 significantly (P = 0.05) improved pregnancy rate (79% versus 58%) as determined by a failure of ewes to return to oestrus within 50 days. The number of ewes that lambed was greatest in the rboIFN-alpha I1-treatment group (71% versus 50%; P = 0.07), and no teratogenic effects were observed in the young born to IFN-treated ewes. The study was repeated a second year with a more fecund group of ewes (Exp. 3). More (P = 0.08) ewes injected with rboIFN-alpha I1 (58/65) than placebo-treated ewes (48/61) were judged pregnant by ultrasound. Again more ewes lambed (55 versus 45) and more lambs were born (98 versus 80) from the rboIFN-alpha I1-treated group. Combining the data from both studies revealed a significant (P = 0.01) effect of treatment. The amount of antiviral activity in jugular vein blood of ewes injected with rboIFN-alpha I1 (2 mg) was determined over time in Exp. 4. Activity rose to a maximum (approximately 450 IRU/ml) within 1-2 h and declined by over 75% in 24 h. Single injections of 1, 2 and 5 mg in buffer or 2 mg emulsified in sesame oil all gave similar profiles of antiviral activity in jugular blood over a 48-h period. In Exp. 5, antiviral activity was measured in uterine vein, ovarian artery and jugular vein serum of untreated pregnant (N = 7) and non-pregnant (N = 11) ewes at Day 15 after mating. Activity was detected in the uterine vein (58 +/- 19 IRU/ml) of all pregnant ewes. The observations in Exps 1-5 are consistent with a role for conceptus-derived IFN-alpha in maternal recognition of pregnancy and suggest that supplemental IFN-alpha might be useful in improving pregnancy success in sheep.

Animals↗