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C S Johnson

Publications and source records attributed to C S Johnson.

At least 37 records · Page 2Linked to original sources
PubMed1999

Perceived social support among depressed elderly, middle-aged, and young-adult samples: cross-sectional and longitudinal analyses.

BACKGROUND: A number of studies have concluded that the perceived quality of support is more strongly associated with mental health than with the actual structure of personal networks. This study examined clinical, historical, and phenomenological variables associated cross-sectionally and longitudinally with perceived social support. METHODS: Participants included elderly, middle-aged, and young-adult depressed samples derived from the Duke Clinical Research Center for the Study of Depression in Late Life. RESULTS: Cross-sectional multivariate analyses revealed that perceived social support was: (1) for the elderly associated with pessimistic thinking, being divorced, having strange ideas, the degree of social interaction, and instrumental support; (2) for middle-age associated with dysthymia, divorce, pessimistic thoughts, social interaction, and instrumental support; and (3) among young adults with instrumental support only. Longitudinal multivariate analyses indicated that only perceived social support at Time 1 predicted perceived social support 1 year later among elderly and middle-aged subjects, whereas only instrumental support predicted perceived social support 1 year later among the young-adult sample. LIMITATIONS: The small number of subjects among the young-adult sample limit conclusions regarding this group. In addition, only patients provided data. Future studies should consider using multiple informants to enhance the accuracy of reported social support. CONCLUSIONS: Our findings indicate that in addition to whatever else they do for depressed patients, clinicians must endeavor to address relationship or social support difficulties, especially in the elderly.

Adult↗
PubMed1999

Correlates of suicidal ideation among an elderly depressed sample.

BACKGROUND: Suicidal ideation has been shown to be strongly associated with suicide completion and elders take their own lives more than any other age group. METHODS: The present study examined clinical and phenomenological correlates of suicidal ideation among an elderly sample (n = 167) derived from subjects enrolled in the Duke Clinical Research Center for the Study of Depression in Late Life. RESULTS: Bivariate results indicated that clinical variables associated with psychomotor retardation, a history of dysthymia, a previous psychiatric in-patient stay, and being a 'younger' elder were related to greater suicidal ideation. Multivariate analyses indicated that feeling guilty, sinful, or worthless was associated with over six times greater odds of having suicidal thoughts. LIMITATIONS: Findings are based on correlational analyses, and thus, the direction of causality cannot be inferred. CONCLUSIONS: This study provides evidence for clinicians of some of the 'red flags' associated with the presence of suicidal ideation among depressed older adults.

Aged↗
PubMed1999

New onset and remission of suicidal ideation among a depressed adult sample.

BACKGROUND: Previous research has demonstrated that suicidal ideation often predicts suicide completion. METHODS: The present study examined clinical and phenomenological variables associated with the presence, development and remission of suicidal ideation among depressed adults. The sample (n = 81) was derived from subjects enrolled in the Duke Clinical Research Center for the Study of Depression in Late Life. RESULTS: Greater pessimistic thinking at baseline predicted the development of suicidal ideation one year later and the older a person was when he or she first experienced depression, the more likely he or she was to report remission from suicidal ideation one year following onset. LIMITATIONS: Longitudinal analyses were based on relatively small samples. Variables that were not significant in these analyses might be in a larger sample. CONCLUSIONS: The longitudinal design of this study mitigates limitations associated with cross-sectional or retrospective designs and advances our understanding of a clinical profile associated with the development and remission of suicidal thoughts.

Adolescent↗
PubMed1999

Effect of treatment for 6 months with human parathyroid hormone (1-34) peptide in ovariectomized cynomolgus monkeys (Macaca fascicularis).

A potential negative side effect of intermittent parathyroid hormone (PTH) therapy to treat osteoporosis is the loss of cortical bone concomitant with increased cancellous bone mass. We addressed this issue by studying the effects of PTH on whole-body, axial, and appendicular bone mass in an animal model with haversian cortical bone remodeling. Ovariectomized, young adult female cynomolgus monkeys were assigned to placebo (n = 9) or PTH groups (n = 10). The PTH group received 10 microg/kg synthetic human PTH(1-34) peptide by subcutaneous injection, 3 days/week for 6 months, and the placebo group received vehicle. Multiple endpoints of bone mass, strength, and turnover in the axial and appendicular skeleton were assessed, including dual-energy X-ray absorptiometry (DEXA), quantitative computed tomography (qCT), analysis of serum (calcium, phosphorus, alkaline phosphatase, osteocalcin, and tartrate-resistant acid phosphatase) and urinary (calcium and creatinine) biomarkers, histomorphometry, and biomechanical testing. Compared with placebo-treated animals, PTH-treated monkeys had no change in whole-body bone mass, but a 6.7% increase in spinal areal bone mineral density (aBMD) was observed. Cortical bone mass measured by qCT at appendicular sites was not affected by PTH treatment, but there were significant increases in cancellous bone mass in the proximal tibia, and a similar trend in the distal radius. Small, transient increases in serum and urinary calcium were observed, but there were no treatment-related effects on other biochemical endpoints. Increased bone formation rate (BFR/BV) in the midradius and midfemur was accompanied by a nonsignificant increase in midfemur porosity. Increased vertebral cancellous bone volume (BV/TV) was associated with greater trabecular and interstitial thickness with no effect on wall thickness. Increases in bone strength were observed in both axial (vertebral maximum stress and load at fracture) and appendicular (femoral neck fracture load) skeleton. Together, these results indicate that PTH therapy in the cynomolgus monkey results in a net gain of spinal and appendicular cancellous bone mass with no adverse effect on cortical bone.

Absorptiometry, Photon↗
PubMed1999

Vitamin D in the prevention and treatment of prostate cancer.

Current approaches to the management of prostate cancer include surgery, radiation therapy, or hormonal manipulation either individually or in combination. With an increase in understanding of the etiology and natural history of prostate cancer, the influence of dietary factors on the disease is becoming more evident. There have been a number of studies in this regard that have demonstrated a relationship between prostate cancer and numerous dietary constituents including vitamins. The fat-soluble vitamins A and D have both been found to affect the growth of prostate cancer in preclinical experiments. Of the two, vitamin D has been the focus of greater attention in recent years, and there are indications that it may be useful both in the prevention and treatment of prostate cancer. This article reviews the current literature in this area to determine if treatment with vitamin D would be a viable management alternative for the patient described in the case study.

Animals↗
PubMed1999

A Phase I trial of calcitriol (1,25-dihydroxycholecalciferol) in patients with advanced malignancy.

Vitamin D is a steroid hormone best known for its activity in regulating calcium and bone metabolism. Epidemiological evidence suggests that vitamin D may play a role in inhibiting the development of colon and prostate cancer. Vitamin D receptors are expressed in many types of malignant cells; in vitro and in vivo vitamin D and vitamin D analogues are active in suppressing the development and inhibiting the growth of numerous human and animal tumors. The major toxicity of the active form of vitamin D, 1,25-dihydroxycholecalciferol (calcitriol), is the induction of hypercalcemia. There are no data indicating the maximum tolerated dose of calcitriol administered every other day (QOD) s.c. We hypothesized that this route and schedule would permit administration of higher doses of calcitriol, which might have anticancer activity. We conducted a Phase I trial of calcitriol given s.c. QOD in patients with advanced solid tumors. Thirty-six patients were entered at doses ranging from 2 to 10 microg QOD; dose-limiting toxicity (hypercalcemia) occurred in three of three patients entered at the 10-microg QOD dose. Hypercalciuria occurred at all dose levels examined. No other toxicity was seen. Assessment of serum calcitriol concentrations by a RIA revealed a decrease in concentration-time curves on day 7 compared to day 1 of therapy. A dose-dependent increase in peak serum level and estimated area under the concentration-time curve was seen. The maximum serum levels occurred at the 10-microg QOD dose: 288 +/- 74 and 321 +/- 36 pg/ml at days 1 and 7, respectively. The normal range of calcitriol serum concentration, determined using this assay, is 16-56 pg/ml. Serum calcitriol levels were maintained at near peak concentrations for at least 8 h following s.c. injection. This study indicates that substantial doses of calcitriol can be administered via this route with tolerable toxicity. Studies to explore approaches to ameliorate the hypercalcemia induced by calcitriol and to explore alternative schedules and interactions with other agents are warranted.

Adenocarcinoma↗
PubMed1998

Enhancement of 1,25-dihydroxyvitamin D3-mediated antitumor activity with dexamethasone.

BACKGROUND: The active metabolite of vitamin D, i.e., 1,25-dihydroxycholecalciferol (1,25-D3), inhibits the growth of murine SCCVII/SF squamous cell carcinoma cells, both in vitro and in vivo. However, in vivo use of 1,25-D3 is hampered as a result of hypercalcemia (i.e., elevated levels of calcium in the blood). Glucocorticoids, such as dexamethasone, affect calcium absorption and modulate vitamin D receptor binding and have been used to treat hypercalcemia. In this study, we examined the effect of dexamethasone on tumor growth inhibition by 1,25-D3. METHODS: The effects of 1,25-D3 and dexamethasone, alone and in combination, on the growth of SCCVII/SF cells in in vitro culture or in vivo in female C3H/HeJ mice were determined by clonogenic tumor cell assay and/or by actual changes in tumor volume. Vitamin D receptor-ligand-binding activities in whole-cell extracts from cells (in culture), tumors, and normal tissues were assayed by single-point saturation analysis and equilibrium binding. RESULTS: Treatment of cultured SCCVII/SF cells with 500 nM dexamethasone for 24 hours before addition of 1,25-D3 reduced their survival. The growth of SCCVII/SF tumors was inhibited in mice treated simultaneously with dexamethasone and 1,25-D3 (as compared with no treatment or single-agent treatment); hypercalcemia was also reduced. Total vitamin D receptor content in SCCVII/SF cells was increased after treatment with dexamethasone. Treatment of tumor-bearing animals with dexamethasone (9 microg/day) for 7 days led to increased vitamin D receptor-ligand-binding activities in whole-cell extracts from tumor or kidneys and decreased activity in intestinal mucosa. CONCLUSIONS: Dexamethasone may enhance the antitumor effect of 1,25-D3 by increasing vitamin D receptor-ligand-binding activity.

Animals↗
PubMed1998

Interleukin-12 gene therapy prevents establishment of SCC VII squamous cell carcinomas, inhibits tumor growth, and elicits long-term antitumor immunity in syngeneic C3H mice.

Interleukin-12 (IL-12) is an immunostimulatory agent with very promising antitumor activity. Using a retroviral expression vector, the authors have successfully transduced the genes encoding the two subunits of murine IL-12 to the squamous cell carcinoma cell line, SCC VII. Once IL-12 gene transcription and protein production were successfully verified, IL-12 expression was found to inhibit the establishment of SCC VII tumors in syngeneic C3H/HeJ mice inoculated with 1 x 10(6) SCC VII/IL-12 viable tumor cells. Mice immunized in this manner and rechallenged with parent SCC VII were capable of rejecting tumor up to 40% of the time. Treatment of established SCC VII tumors with irradiated IL-12-producing tumors cells led to significant tumor regression in a high percentage of animals.

Animals↗
PubMed1997

Potentiation of cisplatin antitumor activity using a vitamin D analogue in a murine squamous cell carcinoma model system.

In a murine squamous cell carcinoma (SCC) model, we have demonstrated that both 1,25-dihydroxycholecalciferol (1,25-D3) and the analogue 1,25-dihydroxy-16-ene-23-yne-cholecalciferol (Ro23-7553) have significant in vitro and in vivo antitumor activity. We have examined here the cell cycle effect of 1,25-D3 and Ro23-7553 on SCCVII/SF tumor cells by quantitating nuclear DNA using a detergent-trypsin method via flow cytometry analysis. Both 1,25-D3 and Ro23-7553 resulted in a significant increase of cells in G0-G1, with an accompanying decrease of cells in S phase. The ability to arrest cells in G0-G1 has been exploited by combining Ro23-7553 with the cytotoxic agent cisplatin (cis-diamminodichloroplatinum; cDDP). Using the in vitro clonogenic assay, pretreatment with Ro23-7553 for 24-48 h significantly enhanced cDDP-mediated tumor cell kill as compared to concurrent treatment with Ro23-7553 and cDDP or cDDP alone. To examine the effect of Ro23-7553 and cDDP in vivo, C3H/HeJ mice with 9-14-day SCC tumors were treated either for 3 days with varying i.p. doses of Ro23-7553 or for 7 days continuously through the use of Alzet pumps, and on the last day of Ro23-7553 treatment, cDDP (1-6 mg/kg) was administered. Using the in vivo excision tumor cell clonogenic assay, in which tumors were removed from animals 24 h after cDDP treatment and plated in a clonogenic assay, pretreatment with Ro23-7553 markedly enhanced cDDP-mediated clonogenic tumor cell kill, even at low doses of cDDP as compared to cDDP treatment alone. Similarly, a significant decrease in fractional tumor volume and increase in tumor regrowth delay was observed when animals were pretreated before cDDP with Ro23-7553 as compared to either agent alone. These results demonstrate a significant enhanced antitumor effect with Ro23-7553 pretreatment before cDDP both in vitro and in vivo and suggest that Ro23-7553 may potentiate cDDP cytotoxicity through effects on cell cycle progression.

Animals↗
PubMed1997

A new immunocompetent murine model for oral cancer.

OBJECTIVE: To develop and characterize a new immunocompetent murine model that attempts to parallel the clinical and biological nature of head and neck cancer. DESIGN: The growth rate and histologic characteristics of the SCC VII/SF cell line were initially determined in tissue culture experiments. Animal experiments were subsequently performed on C3H/HeJ mice. Using direct injection, 5 x 10(5) SCC VII/SF cells were delivered to the floor of the mouth of each animal. Animals were killed after 1, 2, and 3 weeks, and tumor growth, invasion, and regional and distant metastases were evaluated. RESULTS: Squamous cell carcinomas that could be palpated and measured externally were identified in the floor of the mouth of C3H/HeJ mice after 5 to 7 days. Local invasion into the mylohyoid musculature and mandible was present. Cervical lymph node and pulmonary metastases were identified between 2 and 3 weeks. CONCLUSIONS: This study introduces a new oral cancer animal model that shows initial locoregional tumor invasion, direct extension into the neck, early cervical metastases, and pulmonary metastases. These clinical and histopathologic attributes reflect the biological behavior and tumor progression seen in human oral cancer and therefore provide a model for clinically applicable research for primary and metastatic head and neck cancer.

Animals↗
PubMed1997

Interleukin-1alpha synergistic in vivo enhancement of cyclophosphamide- and carboplatin-mediated antitumor activity.

Interleukin-1alpha (IL-1alpha) has potent acute antitumor activity in vivo and can enhance the efficacy of chemotherapeutic drug-mediated antitumor responses. Studies were undertaken to examine the ability of IL-1alpha to enhance the activity of cyclophosphamide (CTX) administered in combination with carboplatin. To determine the in vivo effect of IL-1alpha, CTX and/or carboplatin, mice bearing 14-day RIF-1 tumors were treated on day 0 with a concurrent i.p. injection of varying doses of CTX (5-150 mg/kg), human IL-1alpha (125 microg/kg), and carboplatin (50 mg/kg) and examined 24 h later for the surviving fraction by the in vivo excision clonogenic-tumor-cell assay. Even at the lowest doses of CTX, IL-1alpha significantly enhanced the clonogenic tumor cell kill when compared to treatment with CTX alone. When carboplatin was added to the treatment schema, significantly greater clonogenic cell killing and tumor regrowth delay were observed as compared to any agent alone or a two-drug combination (CTX/IL-1alpha or CTX/carboplatin). Significant enhancement was observed even at low doses of CTX in combination with carboplatin and IL-1alpha. The interaction between the three-drug combination was found to be synergistic as determined by the median dose effect with significant dose reduction apparent for IL-1alpha and CTX when used in this combination. These results demonstrate that IL-1alpha can synergistically enhance the antitumor efficacy of CTX and the combination of CTX and carboplatin.

Animals↗
PubMed1997

Human tumor models in the severe combined immune deficient (scid) mouse.

PURPOSE: To test a number of established human tumor cell lines and early passage breast cancer (UACC2150) and melanoma cells (UACC1273) for growth in the scid mouse and the tumors' response to conventional chemotherapeutic drugs. METHODS: Established melanoma (A375, C81-61), colon (SW480), lung (A549), lymphomoblastoid leukemia (LCL-B), promyelocytic leukemia (HL60), prostate (PC-3, DU145), and breast (MCF7) cell lines were injected at subcutaneous (s.c.), intraperitoneal (i.p.), or mammary fat pad (MFP) sites. Tumor volume growth curves and survival curves were established for the various tumor cell lines. Carmustine (BCNU), cisplatin (CDDP), cyclophosphamide (CPA), doxorubicin, dacarbazine (DTIC), tamoxifen and vincristine were injected s.c. or i.p.. The chemotherapeutic drug effects on tumor volumes and survival were determined. RESULTS: Tumor growth occurred with each cell type. After i.p. injection, 90% mortality occurred within 26 to 60 days except for the early passage melanoma cell line UACC1273 with which mortality occurred within approximately 90 days. In the MCF7 breast model, treatment with tamoxifen (P < 0.001) and CPA (P < 0.0001) resulted in significant tumor growth delay compared with control groups. BCNU and CDDP resulted in significant tumor growth delays relative to control in SW480 colon cancer (P < 0.0014) and A375 melanoma (P < 0.0001) models, respectively. CPA and doxorubicin improved survival in the HL60 leukemia model (P = 0.0018). CONCLUSIONS: These scid mouse human tumor models appear to reflect the clinical situation in that clinically active chemotherapeutic drugs are similarly active in the scid mouse models. Therefore, the scid mouse models may be useful for testing new chemotherapeutic agents against various human cancer types.

Animals↗
PubMed1997

Vitamin D inhibition of prostate adenocarcinoma growth and metastasis in the Dunning rat prostate model system.

OBJECTIVES: Risk factors for prostate cancer (PCa)-related mortality include old age, black race, and residence in northern latitudes. The objectives of this study are to examine the in vitro and in vivo effects of 1,25-dihydroxycholecalciferol (1,25-D3) and less-hypercalcemic analogues on the Dunning rat prostate adenocarcinoma model. METHODS: To evaluate the effect of 1,25-D3 on PCa in vitro, we used the highly metastatic Mat-lylu (MLL) and moderately metastatic R3327-AT-2 (AT-2) Dunning prostate cell lines, and examined effects on growth, clonogenicity, differentiation, and cell cycle. In vivo analysis included examination of the effects of these compounds on tumor growth and metastasis. RESULTS: Using both the 3-day MTT and 7-day clonogenic assay, 1,25-D3 demonstrated a growth inhibitory effect with a concentration for 50% inhibition (IC50) of approximately 20 microM for both MLL and AT-2. Cell cycle analysis of treated MLL cells (10 microM 1,25-D3 for 48 hours) had 25% more cells in the G0/G1 phase than did control cells. To examine the in vivo effect of 1,25-D3 and the less hypercalcemic vitamin D analogue, Ro25-6760 (or 6760), on MLL PCa growth and metastasis, tumors (5 x 10(5) cells) were implanted subcutaneously into the flank of Copenhagen rats on the same day that treatment was initiated with 1,25-D3 (1 microgram) or 6760 (1 or 5 micrograms); rats received treatment three times a week. After 3 weeks, 1,25-D3 and 6760 (5 micrograms dosing) resulted in an inhibition of tumor volume and a reduction in the number and size of lung metastases. CONCLUSIONS: These preclinical studies demonstrate the profound in vitro, or in vivo, or both antiproliferative and differentiating effects of 1,25-D3 and 6760 on PCa and suggest that these drugs may have potential beneficial effects in the treatment of advanced PCa.

Adenocarcinoma↗
PubMed1997

Amifostine protects normal tissues from paclitaxel toxicity while cytotoxicity against tumour cells is maintained.

The objectives of this study were to evaluate the protective effects of amifostine against paclitaxel-induced toxicity to normal and malignant human tissues. Haematopoietic progenitor colony assays were used to establish the number of CFU-GEMM and BFU-E colonies after incubation with WR-1065 alone, Amifostine alone, paclitaxel (2.5 or 5 microM) +/- WR-1065 or amifostine. MTT and alkaline elution assays evaluated the in vitro growth inhibitory and DNA damaging effects, respectively, of paclitaxel with or without amifostine against normal human fibroblasts and human non-small cell lung cancer (NSCLC) cells. This combination was also evaluated in vivo using severe combined immune deficient (scid) mouse models of early (non-palpable tumours) and advanced (palpable tumours) human ovarian cancer. Human 2780 ovarian cancer cells were inoculated subcutaneously while paclitaxel and amifostine were administered intraperitoneally. A brief exposure (15 min) to amifostine not only protected human haematopoietic progenitor colonies from paclitaxel toxicity, but stimulated the growth of CFU-GEMM and BFU-E beyond control values. Amifostine protected normal human lung fibroblasts from paclitaxel-induced cytotoxicity and DNA single-strand breaks. However, paclitaxel cytotoxicity and DNA single-strand breaks were actually enhanced by pretreatment with amifostine in the NSCLC model. Importantly, amifostine did not interfere with paclitaxel antitumour activity even with prolonged exposure (24.5 h) of the lung cancer cells to high concentrations (1.2 mM) in vitro or following five repetitive high doses (200 mg/kg) given to scid mice with human ovarian cancer xenografts. Indeed, under certain circumstances, amifostine resulted in sensitisation of tumour cells to paclitaxel. Our results confirm previous reports of the ability of amifostine to protect normal tissues from the toxic effects of chemotherapy drugs and now extend these observations to paclitaxel.

Amifostine↗
PubMed1997

Prostatic asymmetry as a risk factor for prostatic carcinoma: serial prostate-specific antigen monitoring and cancer detection.

OBJECTIVE: To compare the rates of cancer detection in men with a normal, asymmetric, or suspicious prostate on digital rectal examination (DRE) initially and after 3 years of serial monitoring of prostate specific antigen (PSA) level. PATIENTS AND METHODS: Prostatic 'asymmetry' was defined as asymmetric growth of the lateral lobes of the prostate without induration or nodules, as assessed by a DRE. The study included 963 men with no clinical evidence of prostate cancer and whose serum PSA levels were monitored at 4 month intervals. Prostatic biopsy was recommended if the PSA level became persistently abnormal (> 4ng/mL) or increased by > 20% after having been initially abnormal. Cancer detection rates were compared among groups categorized by the initial DRE findings and serum PSA level. RESULTS: On comparing groups with suspicious and normal DREs, and abnormal with normal PSA levels both, as expected, were associated with a statistically significant increase in cancer detection. However, an asymmetric prostate did not carry an increased risk of detecting prostate cancer when compared with a normal prostate, regardless of PSA level. CONCLUSIONS: An asymmetric prostate does not appear to be an independent risk factor for detecting prostate cancer. Therefore, an asymmetric prostate with no abnormality in PSA level should not mandate prostatic biopsy, or even an increase in monitoring frequency above the presently recommended annual interval.

Aged↗
PubMed1997

Reduced asthma symptoms with n-3 fatty acid ingestion are related to 5-series leukotriene production.

Asthma may respond to dietary modification, thereby reducing the need for pharmacologic agents. This study determined the effectiveness of n-3 polyunsaturated fatty acid (PUFA) ingestion in ameliorating methacholine-induced respiratory distress in an asthmatic population. The ability of urinary leukotriene excretion to predict efficacy of n-3 PUFA ingestion was assessed. After n-3 PUFAs in ratios to n-6 PUFAs of 0.1:1 and 0.5:1 were ingested sequentially for 1 mo each; patient respiratory indexes were assessed after each treatment. Forced vital capacity (FVC), forced expiratory volume for 1 s (FEV1), peak expiratory flow (PEF), and forced expiratory flow 25-75% (FEF 25-75) were measured along with weekly 24-h urinary leukotriene concentrations. With low n-3 PUFA ingestion, methacholine-induced respiratory distress increased. With high n-3 PUFA ingestion, alterations in urinary 5-series leukotriene excretion predicted treatment efficacy. Elevated n-3 PUFA ingestion resulted in a positive methacholine bronchoprovocation dose change in > 40% of the test subjects (responders). The provocative dose to cause a 20% reduction (PD20) in FEV1, FVC, PEF, and FEF25-75 values could not be calculated because of a lack of significant respiratory reduction. Conversely, elevated n-3 PUFA ingestion caused some of the patients (nonresponders) to further lose respiratory capacity. Five-series leukotriene excretion with high n-3 PUFA ingestion was significantly greater for responders than for nonresponders. A urinary ratio of 4-series to 5-series leukotrienes < 1, induced by n-3 PUFA ingestion, may predict respiratory benefit.

Adult↗