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Richard Greenberg

Publications and source records attributed to Richard Greenberg.

5 recordsLinked to original sources
PubMed2004

Impact-induced seismic activity on asteroid 433 Eros: a surface modification process.

High-resolution images of the surface of asteroid 433 Eros revealed evidence of downslope movement of a loose regolith layer, as well as the degradation and erasure of small impact craters (less than approximately 100 meters in diameter). One hypothesis to explain these observations is seismic reverberation after impact events. We used a combination of seismic and geomorphic modeling to analyze the response of regolith-covered topography, particularly craters, to impact-induced seismic shaking. Applying these results to a stochastic cratering model for the surface of Eros produced good agreement with the observed size-frequency distribution of craters, including the paucity of small craters.

Journal Article↗
PubMed2003

Vinblastine and estramustine phosphate in metastatic renal cell carcinoma: a phase II trial of the Fox Chase Network.

BACKGROUND: It is well known that metastatic renal cell carcinoma (RCC) exhibits constitutive resistance to chemotherapeutic agents. Antimicrotubule agents such as vinblastine are associated with low but reproducible response rates (approximately 12%) in patients with RCC. Estramustine has been shown to potentiate the antimicrotubule effects of vinblastine. The authors sought to increase the activity of vinblastine in RCC through the addition of estramustine. METHODS: Twenty-one patients with metastatic RCC not previously treated with chemotherapy received oral estramustine phosphate, 600 mg/m(2), on Days 1, 2, and 3 weekly for 6 weeks, and intravenous vinblastine, 4 mg/m(2) on Day 2 weekly for 6 weeks, repeated every 8 weeks. Twenty-one patients received 31 cycles of therapy. RESULTS: Two patients experienced Grade 3 and 4 hematologic toxicity, and three patients had Grade 3 nonhematologic toxicity consisting of neurologic toxicity, hepatic toxicity, or angioneurotic edema. One patient had a partial response with decreased liver metastases for 48 weeks; 9 patients had stable disease, for a median duration of 14 weeks (range, 11-31 weeks); and 11 patients demonstrated disease progression. The median overall time to progression was 8 weeks and the median overall survival period was 24 weeks. CONCLUSIONS: Although well tolerated, the combination of oral estramustine phosphate with vinblastine administered on this schedule had minimal activity in patients with metastatic RCC.

Adult↗
PubMed2003

Clinical, demographic and psychosocial correlates of complementary and alternative medicine use by men diagnosed with localized prostate cancer.

PURPOSE: We examined complementary and alternative medicine (CAM) use among men who received standard therapy for localized prostate cancer. MATERIALS AND METHODS: A total of 417 men completed a questionnaire 6 months after their treatment decision assessing clinical and psychosocial variables and use of 41 available CAM therapies grouped into the 2 general categories of herbal/dietary and nonherbal (i.e. mind-body, bioelectromagnetic, traditional/folk medicine, pharmacological/biological). RESULTS: The prostate cancer diagnosis prompted 19% of our sample to start using some form of CAM for prostate health, and 67% of men reported having used some form of CAM for prostate health before being diagnosed. Initiation of CAM was associated with being a member of an ethnic minority group and a higher level of education. Initiation of nonherbal CAM was associated with being married, while use of herbal CAM therapies was significantly associated with choosing observation. Herbal use before diagnosis was associated with being white, higher level of education and being single. Prostate specific antigen at diagnosis, Gleason score, quality of life, participant perceptions of seriousness of prostate cancer or self-reported worry about prostate cancer were not related to initiation or prior use. Of those men reporting current use almost 50% did not inform their treating physician of using CAM therapies. CONCLUSIONS: Initiation of CAM therapies as a result of a prostate cancer diagnosis was fairly low, although two-thirds of men had used it before diagnosis. Half of the patients did not inform their physicians about such use and physicians should continue to probe patients about CAM use.

Adult↗
PubMed2002

Voriconazole compared with liposomal amphotericin B for empirical antifungal therapy in patients with neutropenia and persistent fever.

BACKGROUND: Patients with neutropenia and persistent fever are often treated empirically with amphotericin B or liposomal amphotericin B to prevent invasive fungal infections. Antifungal triazoles offer a potentially safer and effective alternative. METHODS: In a randomized, international, multicenter trial, we compared voriconazole, a new second-generation triazole, with liposomal amphotericin B for empirical antifungal therapy. RESULTS: A total of 837 patients (415 assigned to voriconazole and 422 to liposomal amphotericin B) were evaluated for success of treatment. The overall success rates were 26.0 percent with voriconazole and 30.6 percent with liposomal amphotericin B (95 percent confidence interval for the difference, -10.6 to 1.6 percentage points); these rates were independent of the administration of antifungal prophylaxis or the use of colony-stimulating factors. There were fewer documented breakthrough fungal infections in patients treated with voriconazole than in those treated with liposomal amphotericin B (8 [1.9 percent] vs. 21 [5.0 percent], P=0.02). The voriconazole group had fewer cases of severe infusion-related reactions (P<0.01) and of nephrotoxicity (P<0.001). The incidence of hepatotoxicity was similar in the two groups. Patients receiving voriconazole had more episodes of transient visual changes than those receiving liposomal amphotericin B (22 percent vs. 1 percent, P<0.001) and more hallucinations (4.3 percent vs. 0.5 percent, P<0.001). Parenteral voriconazole was changed to the oral formulation in 22 percent of the voriconazole group, with a reduction in the mean duration of hospitalization by one day in all patients (P=0.17) but by two days in patients at high risk (P=0.03). CONCLUSIONS: Voriconazole is a suitable alternative to amphotericin B preparations for empirical antifungal therapy in patients with neutropenia and persistent fever.

Adolescent↗