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31.
Summary LL-D491941 is a new cytotoxic antibiotic selected for clinical phase I study because of its impressive pre-clinical anti-tumour activity and its low toxicity profile in experimental animals. A total of 15 patients were treated in centres in Glasgow and Amsterdam at doses ranging from 0.25 to 4 mg/m2. One minor response was noted in a patient with colonic carcinoma. The study was suspended following the discovery of unexpected cardiotoxicity. As this toxicity was not consistent with the standard (EORTC) European Organisation for Research and Treatment of Cancer toxicology profile, we chose to investigate the pharmacokinetics of LL-D491941 in mice and humans in more detail to try to explain this phenomenon. A major difference in plasma protein binding was discovered between mice and patients, with a suggestion of non-linear kinetics being noted at higher doses in humans. It is likely that these differences in drug handling account for the unexpected and serious toxicity encountered in this trial.  相似文献   
32.
Breast cancer is the most common malignancy in women, accounting for about 18% of female cancers, and over half a million new cases are diagnosed worldwide each year. Its incidence increases with age and is currently rising. Although the increased availability of screening programs has allowed earlier detection and treatment of primary breast cancers, many patients relapse with metastases after apparently successful treatment of their primary tumor and over 15,000 women in the UK and about 50,000 in the USA die from advanced disease each year. The natural course of breast cancer is very variable even after the development of metastases, and depends on a variety of tumor characteristics and prognostic factors. This is reflected in the large number of treatments currently employed. However, despite this wide choice and considerable research over the years, treatment of metastatic breast cancer (MBC) prolongs average survival times only slightly. Current therapy is aimed at achieving a balance between producing maximal tumor shrinkage to produce the most effective possible palliation of symptoms, and minimizing adverse effects. Anticancer chemotherapy is the preferred option in patients who do not respond to hormones, those with hormone-independent tumors, those with aggressive breast cancer subtypes. A variety of anticancer chemotherapy regimens, using both single and combined agents, have been shown to be effective in achieving tumor regression in MBC. Anthracyclines (doxorubicin, epirubicin) are the most active of the established monotherapies, typically producing response rates of 50-60% during initial (first-line) treatment for metastatic disease, but being effective in fewer than 25% of patients requiring second-line therapy. The drawbacks of anthracyclines include dose-limiting cumulative cardiotoxicity and the development of resistant tumor clones after the use of anthracyclines for adjuvant or first-line therapy, especially if subsequent courses are required within a year. The success of these established chemotherapeutic agents depends greatly on the number and location of metastatic sites. Lymph node and soft tissue secondaries tend to respond well, while visceral metastases (especially in the liver) carry a particularly poor prognosis despite treatment. The outlook for patients with metastases involving more than two organ systems is also bleak. Although some patients can live for years with metastatic disease, the average survival time in patients with MBC is 18-24 months, while in those with liver metastases, life expectancy averages only 6 months. High-dose anticancer chemotherapy with granulocyte-colony stimulating factor (G-CSF) or autologous bone marrow transplantation has allowed the dose intensity of anthracyclines to be increased, and has improved the response rate to about 70% in selected patients with MBC. However, this approach has not been proven to improve survival, involves the risk of greater toxicity and drug-related mortality, and patients with reduced clearance of anthracyclines due to hepatic dysfunction from liver metastases may not be suitable candidates. A number of new anticancer agents have also recently been introduced in an attempt to improve on the performance and avoid the tolerability problems associated with anthracyclines. Among these, antitubulin agents (taxoids and vinorelbine) have shown highly promising activity in MBC. This paper reviews the preclinical, phase I and phase II data for one taxoid, docetaxel. Docetaxel (Taxotere) belongs to the taxoid class of cytotoxic agents, the development of which began more than 20 years ago. In 1971, paclitaxel (Taxol) was identified as the active compound of the crude extract of the bark of the Pacific Yew tree Taxus brevifolia. However, at that time the development of paclitaxel was hampered because of the limited source of the drug and difficulties with isolation, extraction and formulation. The second active taxoid, docetaxel, was isolated by Potier et al. in 1986. Docetaxel is prepared from a non-cytotoxic precursor, extracted from the needles of the European Yew tree Taxus baccata, that is condensed with a chemically-synthesized side-chain. As the docetaxel precursor is freely available because of the regenerating capacity of the needles the development of docetaxel has thus been rapid.  相似文献   
33.
PURPOSE:: To test the antitumor activity of Elsamitrucin in metastaticcancer of the breast, colon and rectum, non-small cell lungand ovary. PATIENTS AND METHODS:: Eligibility required histologically proven cancer. Patientswith colorectal or non-small cell lung cancer could not havereceived prior chemotherapy. Patients were entered if WHO PSwas 2 and organ functions were normal. Treatment consisted ofElsamitrucin 25 mg/m2/week given as a 5–10 min infusionfor at least 3–6 weekly doses. RESULTS:: One hundred and five patients entered the studies, 97 were eligible,94 are evaluable for toxicity and 75 for response. Toxicitymainly consisted of mild nausea/vomiting, and less frequentlyreversible hepatotoxicity and malaise. No objective responseswere seen. CONCLUSION:: Elsamitrucin at this dose and schedule is not an active drugin metastatic breast cancer, colorectal cancer, non-small celllung cancer or ovarian cancer. Elsamitrucin, phase II, breast, colorectum, nonsmall cell lung, ovary  相似文献   
34.
A four years-old boy with Xanthogranulomatous pyelonephritis was surgically treated at the Pediatric Surgery Unit of the Santa Casa de Misericórdia of Maceió. Comments are made upon pathology, pre-operative diagnostic difficulties, differential diagnosis, and the rare occurrence in children.  相似文献   
35.
OBJECTIVE: To evaluate a cardiovascular nutrition education package designed for African-American adults with a wide range of literacy skills. DESIGN: Comparison of a self-help group and a full-instruction group; each group received nutrition counseling and clinical monitoring every 4 months. SUBJECTS: Three hundred thirty African-American adults, aged 40 to 70 years, with elevated cholesterol level or high blood pressure were randomly assigned to the self-help or full-instruction group; 255 completed the 12-month follow-up. INTERVENTIONS: Counseling to reduce intake of dietary fat, cholesterol, and sodium was based on Cardiovascular Dietary Education System (CARDES) materials, which included food-picture cards, a nutrition guide (self-help and full-instruction group), a video and audiotape series, and 4 classes (full-instruction group only). MAIN OUTCOME MEASURES: Changes in lipid levels and blood pressure after 12 months. STATISTICAL ANALYSES PERFORMED: Primary analyses consisted of repeated-measures analysis of variance to examine effects of time and randomization group on outcomes. RESULTS: Total cholesterol and low-density lipoprotein cholesterol level decreased by 7% to 8% in the self-help and full-instruction groups of men and women (P < .01). The ratio of total cholesterol to high-density lipoprotein cholesterol (HDL-C) decreased in both groups of women and in the men in the full-instruction group (P < .01). In full-instruction and self-help participants with elevated blood pressure at baseline, systolic blood pressure decreased by 7 to 11 mm Hg and diastolic blood pressure decreased by 4 to 7 mm Hg (P < .01). Outcomes did not differ by literacy scores but were positively related to the reported initial frequency of using CARDES materials. APPLICATIONS/CONCLUSIONS: These results suggest that periodic nutrition counseling based on CARDES materials used for home study can enhance management of lipid levels and blood pressure in African-American outpatients.  相似文献   
36.
Systemic administration of the mitochondrial toxin 3-nitropropionic acid (3-NP) to rats results in selective striatal lesions and serves as an experimental model of Huntington's disease (HD). However, the effects of the 3-NP treatment are unpredictable and result in lesions of variable severity. The present study was aimed at further characterizing the variability of the striatal lesions induced by systemic administration of 3-NP using osmotic pumps. Hematoxylin-eosin (HE) and Nissl stains as well as immunohistochemical labelling of astrocytes and striatal neurones were performed to analyse the neurotoxic effects of 3-NP. In general, chronic systemic administration of 3-NP resulted in obvious bilateral striatal lesions, which ranged from mild to severe, together with a subtle, but detectable behavioural lesion. Severe type lesions showed marked neuronal loss and an increased expression of glial fibrillary acidic protein (GFAP) in astrocytes surrounding the lesion area, whereas in the core of the lesion GFAP-immunoreactivity was absent. The mild type lesion was characterized by a substantial loss of striatal neurones and an increased expression of GFAP-positive astrocytes throughout the lesion. In a number of 3-NP-treated animals, neither type of lesion was observed, although these animals demonstrated behavioural changes in the paw test compared to controls. In the striatum of these tested 3-NP-treated animals, compromised rk' neurones were detected, suggestive of subtle and early 3-NP-induced neuronal injury. Similar dark neurones were also detected in mild and severe lesions and were immunocytochemically characterized as gamma-aminobutyric acid (GABA) and substance P containing spiny neurones, which belong to the neuronal population that is affected in early HD. These results indicate that systemic administration of 3-NP to rats may result in a spectrum of striatal pathology of which the morphology of the mild type lesion resembles the characteristic HD neuropathology most closely.  相似文献   
37.
Marrow regeneration after mechanical depletion   总被引:1,自引:0,他引:1  
Brecher  G; Tjio  JH; Smith  WW; Haley  JE 《Blood》1976,48(5):679-686
The origin of marrow regeneration after mechanical depletion was reinvestigated in mouse chimeras. The results were compatible with the local origin of stem cells from remnants of incompletely removed marrow, but not with their origin from a common precursor of both bone and hemopoietic cell lines. In transplanted femurs depleted by a modified technique of in vivo evacuation of marrow, hemopoietic regeneration failed to occur. The presence of hemopoietic stem cells in the Haversian canals was thus excluded. The demonstration of ample hemopoiesis with minimal bone formation in nondepleted controls in which bone marrow initially became necrotic provided new evidence that osteogenesis was not a prerequisite of hemopoietic regeneration.  相似文献   
38.
39.
The purpose of the present study was to identify a subset of high-risk patients among surgically treated node-positive patients with stage IB and IIA cervical carcinoma. From 1982 through 1991, 334 patients underwent radical hysterectomy for FIGO stage IB and IIA cervical carcinoma. In 68 patients pathological analysis of the surgical specimen revealed positive pelvic nodes. In this group, a Cox proportional hazard analysis was performed to examine the prognostic significance of clinicopathological variables. Only for adenocarcinoma (P= 0.002) and parametrium infiltration (P= 0.003) was evidence of an association with prognosis found. Based on these two factors, patients with positive pelvic nodes were categorized into a low-risk group (squamous cell carcinoma without parametrium infiltration,N= 33) and a high-risk group (squamous cell carcinoma with parametrium infiltration or adenocarcinoma,N= 34). The 5-year disease-specific survival in the low-risk group was 94% compared with 60% in the high-risk group (P= 0.003). For patients in the high-risk group, there is an urgent need for alternative adjuvant treatment to improve outcome.  相似文献   
40.
The antitumor activity of zeniplatin, a third-generation, water-soluble platinum compound that has shown broad preclinical antitumor activity and no significant nephrotoxicity in phase I trials, was tested in patients with advanced malignant melanoma and advanced renal cancer. Patients who had not previously been treated, except with local limb perfusion and immunotherapy, were given zeniplatin as bolus injections at 125 mg/m2 every 3 weeks. The main hematological toxicity was leukopenia (7/30 patients, WHO grade ≥ 3) and the main nonhematological toxicity was nausea and vomiting (21/30 patients, WHO grade ≥ 2). Serious nephrotoxicity was observed early in the renal cancer study and, later, also in the melanoma study. Hyperhydration did not prevent the nephrotoxicity, and the studies were stopped after 6 renal cancer patients and 24 malignant melanoma patients had been included. Zeniplatin gave objective responses in 3 of the 21 evaluable malignant melanoma patients [2 complete responses (CRs) in patients with lymph-node metastases lasted 5 and 14 months, respectively; 1 partial response (PR) in a patient with lymph-node and liver metastases lasted 6 months]. In the renal cancer study, only four patients were evaluable for response and none responded. The results show that zeniplatin has some activity (14%) in patients with advanced malignant melanoma, but no conclusion can be drawn regarding the activity of zeniplatin in renal cancer as the number of patients was too low. The main toxicities were leukopenia and nausea and vomiting. Unexpected and serious nephrotoxicity was observed, and for this reason the studies were terminated before the planned number of patients had been included. A possible explanation for the nephrotoxicity may be drug interactions, but no firm conclusion can yet be drawn. Received: 16 March 1996 / Accepted: 25 March 1997  相似文献   
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