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Gene expression of progesterone receptor isoforms in the rat brain.

Progesterone receptors (PRs) are known to exist in two forms: a larger molecular, form B, and a smaller one, form A. Rat PR cDNA corresponding to the region around the translation-initiation site (ATGB) of the putative PR form B mRNA was cloned, together with cloning of steroid-binding domain of the PR forms A and B. An imperfect "estrogen responsive element," GGTCG*** TGACT, was located around ATGB of the rat PR cDNA. The distribution of PR mRNA-containing neurons was mapped in the female adult rat brain by in situ hybridization, which was largely in agreement with that of PR proteins. Differential intracerebral distribution of the mRNAs, measured by the quantitative RT-PCR Southern blotting assay, was found between the total (A+B) and form B mRNA levels, indicating possible distinct mechanisms responsible for regulation of the expression of the PR mRNAs. A region-specific and stage-related gene expression of form B seems predominantly to be "turned on" first around birth, followed by that of form A around Days 8-12. The postnatal developmental pattern of PR form B mRNA in the cerebral cortex resembled that of the PR proteins. Noninducibility of the cortical PR by estrogen might be ascribable to the predominance of form B mRNA, which was reported to have little or no estrogen inducibility. A missmatch existed between PR from A and its mRNA levels, suggesting some impairment of the synthesis of form A. Thyroid hormone may be a regulator of gene expression of the receptor in the developing cortex.

Amino Acid Sequence↗

Mutations in the f165(1)A and f165(1)E fimbrial genes and regulation of their expression in an Escherichia coli strain causing septicemia in pigs.

Transposon (TnphoA) mutagenesis was used to study the expression of F165(1) fimbriae, related to Prs fimbriae, in the pathogenic Escherichia coli strain 5131 (O115:K "V165":F165). This strain causes septicemia in swine and also expresses F165(2) fimbriae, related to F1C. Adhesin-defective mutants from the wild-type pathogenic strain were produced and TnphoA insertions were localized either in the f165(1)A gene, which encodes the major fimbrial subunit or in the f165(1)E, gene, which encodes a minor fimbrial subunit. TnphoA gene fusions were used to measure expression of F165(1) fimbrial genes. Similar pattern of regulation of expression was observed in both f165(1)A and f165(1)E genes. Optimal expression of F165(1) fimbriae was obtained on solid minimal medium. Production of F165(1) fimbriae was negatively regulated by addition of glucose, leucine or alanine to the media, by growth at 18 degrees C, and by pH above or below 7.0.

Animals↗

Role of phosphorus in (Im)mobilization and bioavailability of heavy metals in the soil-plant system.

A large number of studies have provided conclusive evidence for the potential value of both water-soluble (e.g.. DAP) and water-insoluble (e.g., apatite, also known as PRs) P compounds to immobilize metals in soils, thereby reducing their bioavailability for plant uptake. It is, however, important to recognize that, depending on the nature of P compounds and the heavy metal species, application of these materials can cause either mobilization or immobilization of the metals. Furthermore, some of these materials contain high levels of metals and can act as an agent of metal introduction to soils. Accordingly. these materials should be scrutinized before their large-scale use as immobilizing agent in contaminated sites. Although mobilization by certain P compounds enhances the bioavailability of metals, immobilization inhibits their plant uptake and reduces their transport in soils and subsequent groundwater contamination. Whenever phytoremediation of contaminated sites is practicable, appropriate P compounds can be used to enhance the bioavailability of metals for plant uptake. Removal of metals through phytoremediation techniques and the subsequent recovery of the metals or their safe disposal are attracting research and commercial interests. Phosphate compounds can be used to enhance the solubilization of metals, leading to their increased uptake by plants. However, when it is not possible to remove the metals from the contaminated sites by phytoremediation, other viable options such as in situ immobilization should be considered as an integral part of risk management. One way to facilitate such immobilization is by altering the physicochemical properties of the metal-soil complex by introducing a multipurpose anion, such as phosphate, that enhances metal adsorption via anion-induced negative charge (i.e., CEC) and metal precipitation. It is important to recognize that large-scale use of P compounds can lead to surface and groundwater contamination of this element. It is therefore, important that future research should aim to focus on the role of P compounds on in situ remediation and natural attenuation in metal-contaminated sites, with minimum impact of P on quality of water sources.

Biological Availability↗

Phase II study of ifosfamide as a single drug for relapsed paediatric patients.

A total of 22 patients with different solid tumours refractory to previous chemotherapy were treated between May 1985 and December 1986 (osteosarcoma, 7; Wilms' tumour, 6; rhabdomyosarcoma, 2; Ewing's sarcoma, 2; non-Hodgkin's lymphoma, 2; retinoblastoma, 1; cavum lymphoepithelioma, 1; dyktioma, 1). Patients were aged between 3 and 20 years (mean, 10.6 years). There was a 3.4:1 male-to-female ratio. The treatment consisted of ifosfamide given i.v. as a single agent at a dose of 3,000 mg/m2 over 1 h on days 1 and 2. Mesna was given as a uroprotector at 600 mg/m2 every 4 h, up to a total of 13 doses. The courses were repeated every 3 weeks. Every patient except those with osteosarcoma had previously received cyclophosphamide. There were 3 (13.6%) complete responses (CRs) in 2 osteosarcomas and 1 abdominal non-Hodgkin's lymphoma, lasting 12, 8 and 2 months, respectively; 4 (18.2%) partial responses (PRs) in 2 Wilms' tumours, 1 Ewing's sarcoma and 1 abdominal non-Hodgkin's lymphoma; 4 absences of remission (ARs); and 11 (50%) cases of progressive disease (PD). In all, 81 courses were given, and the toxicities found were leukopenia (less than 2,000 leukocytes) in 15 courses, thrombocytopenia in 3, microhaematuria in 7, neurotoxicity in 8, fever in 8 and hypertension in 2. The overall response rate (31.8%) was encouraging and the toxicity, acceptable and reversible. These results demonstrate that ifosfamide should be considered for introduction into phase III protocols for the treatment of solid malignancies in children.

Adolescent↗

A phase II study of ifosfamide in paediatric solid tumours.

A total of 20 children with recurrent or unresponsive tumours (10 Wilms' tumours, 3 rhabdomyosarcomas, 4 Ewing's sarcomas, 1 osteosarcoma, 1 hepatoblastoma, 1 hepatoma) were given ifosfamide as a 24-h infusion (5 g/m2), with mesna as a uroprotector. The number of courses ranged from 1 to 13 (median, 3), and the interval between them was 2-3 weeks. In all, 16 of these patients had previously received cyclophosphamide. Complete clinical responses (CRs) were seen in 3 cases (2 Wilms' tumours and 1 Ewing's sarcoma) and lasted 5, 7, and 9 months. Partial responses (PRs) were seen in 3 instances; mixed response or stable disease, in 4; and progressive disease, in 10. Treatment was well tolerated in most patients, with no cystitis or severe myelosuppression, but two children developed transient neurological symptoms and one became hypertensive. Nausea and vomiting were controlled by high-dose dexamethasone in most children.

Adolescent↗

Very high dose chemotherapy with autologous bone marrow rescue in adult patients with resistant relapsed lymphoma.

Seventeen patients with advanced lymphoma were treated with high-dose chemotherapy with autologous bone marrow rescue. In 11 patients with non-Hodgkin's lymphoma (NHL) there were 2 complete remissions (CRs) and 2 partial remissions (PRs), and in 6 patients with Hodgkin's disease there were 5 CRs. Three patients remain well in unmaintained remission (days 874, 446 and 351), and a further 2 are alive and still receiving treatment (days 650 and 558). This type of therapy appears useful and should now be considered earlier in the course of the disease.

Adult↗

Treatment of acute myeloid leukemia and blastic phase of chronic myeloid leukemia with combined eflornithine (alpha difluoromethylornithine) and methylglyoxal-bis-guanyl hydrazone (methyl-GAG).

A combined eflornithine-MGBG treatment was studied in patients with acute myeloid leukemia (AML) or blastic transformation of chronic myeloid leukemia (BT CML). The first ten patients (5 AML, 5 BT CML) received i.v. or p.o. eflornithine 6 g m-2 day-1 and i.v. MGBG 500 mg/m2 once a week. The duration of treatment was 5-37 days (median 15) with one to five MGBG infusions (median 2). The results were complete response (CR) in one patient, partial response (PR) in four, minimal response (MR) in one and failure (F) in four. Pronounced side effects, including severe mucositis, gastrointestinal disturbances and skin infiltration, were observed in eight patients. As the four PRs were achieved in patients with BT CML, it was decided also to study ten patients with this indication. In attempts to decrease the incidence and severity of unwanted effects, lower doses of eflornithine-MGBG were used, i.e., eflornithine 4 g m-2 day-1 and MGBG 200 mg m-2 once a week. The duration of treatment was 9-110 days (median 46), with 2-14 MGBG infusions (median 6). Responses observed were CR in two patients (in one of whom it was only transient), transient PR in two, transient MR in four, and F in two. Treatment at lower doses was better tolerated, thus allowing a longer duration of treatment. Five of ten patients had moderate or severe gastrointestinal disturbances and one patient had a severe subjective hearing loss. The eflornithine-MGBG combination may prove to be a useful alternative treatment for AML and BT CML, but comparative trials will ultimately be necessary for a more definitive assessment of the combination.

Adult↗

Phase II study of carboplatin in recurrent ovarian cancer: severe hematologic toxicity in previously treated patients.

Carboplatin (CBDCA) is a second-generation cisplatin analog that has shown activity in early clinical trials. Its spectrum of toxicity is quantitatively and qualitatively different from that of the parent compound. Between November 1984 and September 1986 we conducted a phase II trial of CBDCA in 46 women with epithelial ovarian cancer. All patients had undergone at least one prior chemotherapy regimen; 41 (89%) had previously received cisplatin (mean cumulative dose, 540 mg/m2). The CBDCA dose was based on renal function and was injected i.v. once every 4 weeks. Patients were stratified on the basis of baseline creatinine clearance: those with a baseline creatinine clearance of greater than or equal to 60 ml/min received 400 mg/m2 CBDCA; those with a creatinine clearance between 30 and 60 ml/min received an initial dose calculated according to a previously published formula that corrected for renal insufficiency and projected nadir platelet counts of 75,000/mm3. Of 41 evaluable patients, 6 (15%) had an objective response [2 complete responses (CRs); 4 partial responses (PRs)]; 5 of the 6 responders had previously responded to cisplatin treatment. No responses were observed in 12 patients who had not responded to prior cisplatin therapy. Significant hematologic toxicity was seen. Of 18 patients with a creatinine clearance of greater than or equal to 60 ml/min (dose, 400 mg/m2), 6 had nadir platelet counts of less than 25,000/mm3, 4 with symptomatic bleeding. Of the 21 evaluable patients for whom the dose-modification formula was applied, 10 had nadir platelet counts of less than 75,000/mm3; 5 had counts of less than 50,000/mm3. CBDCA has activity even in patients who have previously undergone extensive cisplatin therapy; however, its toxicity is variable and thrombocytopenia is dose-limiting. We did not confirm the ability of the above-mentioned formula to calculate the CBDCA dose and accurately predict the nadir platelet count for all patients. Other factors, such as prior radiotherapy, may also be important in the dosing of CBDCA in pretreated patients.

Acute Disease↗

Linkage of phosphoribosylpyrophosphate synthetases 1 and 2, Prps1 and Prps2, on the mouse X chromosome.

The X Chromosome (Chr) genes for phosphoribosylpyrophosphate synthetases 1 and 2, Prps1 and Prps2, were mapped on the mouse X Chr with interspecific backcrosses between C57BL/6 (B6) and M. spretus (S). Southern analysis showed that Prps1 mapped between Plp and DXWas31, a mouse X Chr region that is homologous to Xq21-24 on the human X Chr while Prps2 mapped between DXWas31 and Amg, a region that is homologous to the map position of PRPS2 on Xp22 of the human X Chr. Additionally, other restriction fragments highlighted by PRS II showed autosomal segregation. In situ hybridization and FISH analysis of metaphase chromosome spreads prepared from lymphocytes of B6 or S male mice confirmed that there were in fact two different locations on the X Chr, X F1-2 and X F2-3 for Prps1 and 2 respectively, as well as two autosomal sites for Prps-like genes.

Animals↗

Characterization of a benzoate permease mutant of Pseudomonas putida.

A spontaneous mutant of Pseudomonas putida (PRS 2017) has been isolated which is incapable of growth on benzoate, does not induce the enzymes of the catechol branch of the beta-ketoadipate pathway when grown in the presence of benzoate, cannot accumulate radioactively labeled benzoate, yet grows well with mandelate as sole source of carbon and energy. This strain apparently lacks a benzoate permease, which in the wild type shows a Km of about 0.1 mM for benzoate, is inducible, and is not under the control of the regulatory system which governs the induction of the enzymes of the catechol branch of the beta-ketoadapate pathway. The lesion in PRS2017 is apparently single site and maps near other genes governing benzoate dissimilation.

Adipates↗

Phase I trial of combined therapy with bleomycin and the calmodulin antagonist, trifluoperazine.

Calmodulin antagonists, such as trifluoperazine, can enhance the cytotoxic effects of bleomycin both in tissue culture and in vivo. Therefore, we evaluated the effects of combination treatment with these drugs in a phase I clinical trial. Patients with objectively measurable or evaluable cancer refractory to conventional treatment who had an acceptable performance status (ECOG 0-2) and acceptable laboratory studies were eligible. All patients gave written informed consent. A cycle of therapy consisted of three weekly treatments with trifluoperazine (days 1-4) and 30 IU bleomycin (day 3). After three patients completed a cycle of therapy without experiencing dose-limiting toxicity, new patients were entered in the study and received a higher dose of trifluoperazine. The dose of bleomycin remained constant. Evaluable patients received at least 2 weeks of treatment and survived for 6 weeks; of 19 patients, 2 were unevaluable. The major toxicities were neurological and pulmonary and included one case of fatal pneumonia with interstitial pulmonary fibrosis. There was no hematologic toxicity. Two patients underwent partial responses (PRs) and two had complete responses (CRs). We conclude that trifluoperazine can safely be given with bleomycin and that further study of the potential efficacy of this treatment is indicated.

Adult↗

Salvage chemotherapy containing moderate-dose cytosine arabinoside and mitoxantrone for relapsed and resistant acute myeloid leukaemia.

A total of 29 evaluable patients with acute myeloid leukaemia (AML) either in relapse or resistant to initial induction daunorubicin-containing chemotherapy were given a salvage regimen consisting of moderate-dose cytosine arabinoside and mitoxantrone. There were 8 (28%) complete responders (CRs), 4 (14%) partial responders (PRs), and 17 (52%) nonresponders. The duration of CRs was 2+, 2+, 3+, 3, 4+, 4, 5 and 6 months respectively. Two of the eight CR patients were refractory to initial daunorubicin-containing induction therapy and another two had achieved a previous CR lasting less than 6 months. Four of the eight CR patients had received an amsacrine-containing salvage regimen (ATA) prior to administration of the present moderate-dose cytosine arabinoside and mitoxantrone regimen; this indicates the lack of absolute clinical cross-resistance between the present combination and the daunorubicin- or amsacrine-containing regimens. However, the duration of CRs achieved by these patients remains very short and should, if possible, be followed by allogeneic or autologous bone marrow transplantation.

Acute Disease↗

Treatment of metastatic breast cancer with the combination of ifosfamide, epirubicin and 5-fluorouracil.

An ongoing trial of combination chemotherapy using ifosfamide (Holoxan), epirubicin and 5-fluorouracil was started in 1987. A total of 30 patients with metastatic cancer of the breast received 1.5 g/m2 i.v. ifosfamide over 60 min on days 1-3, 50 mg/m2 i.v. epirubicin on day 1 and 500 mg/m2 i.v. 5-fluorouracil on day 1, followed by mesna (Uromitexan) given at 20% of the ifosfamide dose at 0, 4 and 8 h. The courses were repeated every 4 weeks. In all, 198 courses were given, ranging from 3 to 13 (median, 7) cycles/patient. The mean age of the 30 patients was 48 years (range, 35-66 years); 5 had not previously received chemotherapy and the others had failed prior cytotoxic and endocrine therapy. Overall, 28 patients were evaluable, 7 (25%) showed a complete response and 15 (54%) had a partial response, for an overall response rate of 22/28 (79%). Three patients showed stable disease with improved symptoms, and in three cases disease progression occurred. The median duration of response was 9 months (range, 3-20 months). Median survival was 11 months for all patients, 15 months for CRs, 10 months for PRs, 6 months for stable disease and 12 months for progressive disease (PD). Survival for the 22 responding patients was 12 months. Toxicity was acceptable and included alopecia, mucositis, nausea, vomiting, diarrhoea, mild cystitis and myelosuppression. Epirubicin did not appear to produce cardiac toxicity, and ifosfamide with mesna did not seem to result in severe urotoxicity. Chemotherapy with ifosfamide, epirubicin and 5-fluorouracil proved to be effective for treatment of advanced breast cancer and should be further studied in large, controlled trials.

Adult↗

Epirubicin and ifosfamide in patients with refractory breast cancer and other metastatic solid tumours.

The combination of ifosfamide (IFO) and epirubicin (EPI) has been found to be an effective regimen in the treatment of metastatic tumours and shows remarkable activity in heavily pretreated breast cancer patients. A combination of EPI (35 mg/m2 on days 1 and 2) and IFO (1.8-2.5 g/m2 on days 1-5) was given to 58 patients with refractory breast cancer (n = 23), metastatic sarcomas (n = 15) and other solid tumours (n = 20). Due to extensive prior therapy, the IFO dose had to be adapted to the individual haematological situation. In all, 55 patients were evaluable; we observed 5 complete (CRs) and 16 partial responses (PRs). In addition, 18 patients experienced a minor response (MR) or no change (NC). The median duration of all responses was 6.7 months. Toxicity was generally mild and closely related to previous therapy.

Antineoplastic Combined Chemotherapy Protocols↗

Palliative chemo-radiotherapy with ifosfamide and epirubicin as first-line treatment for high-risk metastatic breast cancer. Results of a prospective multicenter trial.

From June 1986 to December 1988, 107 patients (median age, 49 years; median performance score, 1) with haematogeneous metastases from breast carcinoma were treated with concomitant radiation and chemotherapy. Overall, 97% of the patients had been pretreated with surgery; 65%, with radiation; and 56%, with hormones. In all, 38% had received adjuvant chemotherapy. Patients with prior palliative chemotherapy were excluded from the study. All patients fulfilled at least two high-risk criteria. Chemotherapy was given according to the EI protocol (4-epirubicin and ifosfamide), and all patients simultaneously received radiation to the main tumour sites. Gastro-intestinal toxicity was moderate (11.1%, WHO grade 4), and bone marrow depression was marked in all cases. After three treatment courses, the overall response rate was 67% [21% complete response (CR), 46% partial response (PR)]. In all, 28% had stable disease (NC) and the rate of progressive disease (PD) was 5%. The median duration of tumour response was 8 months, with 12 months for CRs, 9 months for PRs and 6 months for NCs. The median survival was 13.5 months.

Adult↗

Phase II trial of carboplatin or iproplatin in cervical cancer.

From July 1984 to November 1987, 89 patients with recurrent measurable squamous-cell cancer of the uterine cervix were randomized in a single institution to receive treatment with either carboplatin (CBDCA) or iproplatin (CHIP). Objective response rates were similar: 2 complete regressions (CRs) and 10 partial regressions (PRs) were recorded both in the 46 evaluable patients treated with CBDCA (response rate, 26.1%; 95% confidence interval, 15-41%) and in the 40 evaluable patients treated with CHIP (response rate, 30%; 95% confidence interval, 17-47%). The median duration of response was 5.5 months for CBDCA and 6 months for CHIP; the median survival was 7.5 and 7.6 months, respectively. Both drugs were given in an outpatient setting and myelosuppression (thrombocytopenia) was the predominant toxicity. Analysis of all toxic events yielded additional interesting observations: the occurrence of moderate to severe platelet nadirs beyond cycle 1 was confined to CHIP, a higher incidence of gastrointestinal toxicity during treatment with CHIP, and five moderate to severe complaints of asthenia (recorded as neurologic events) during CHIP therapy versus only one during treatment with CBDCA. Because of its antitumor activity and its toxicologic advantage, a future role for CBDCA in the treatment of cervical cancer appears likely.

Antineoplastic Agents↗

Follow-up study of combination treatment (TAE and PEIT) for unresectable hepatocellular carcinoma.

The subjects were 35 patients with unresectable hepatocellular carcinoma. The patients were divided into a transcatheter arterial embolization group (TAE group, 18 cases) and a combination therapy group receiving both TAE and percutaneous ethanol injection therapy (TAE+PEIT group, 17 cases). The 50% survival period was 21.1 months for the TAE group and 37.8 months for the TAE+PEIT group (P < 0.05). The longest survival period in the TAE group was 89 months. In the TAE+PEIT group, one patient has survived for 59 months. The actuarial 1-, 2-, and 3-year survival rates for the TAE group were 82%, 45%, and 22%, respectively. For the TAE+PEIT group the rates were 83%, 64%, and 64%, respectively. The TAE+PEIT group showed a significantly higher survival rate in the 895- to 1,074-day period as compared with the TAE group (P < 0.05). Overall, the survival rate tended to be higher in the TAE-PEIT group (P < 0.1). The therapeutic responses of tumors were measured by the maximal reduction rate within 6 months of TAE and PEIT. In the TAE group, a PR was seen in only four cases. In the TAE+PEIT group, CRs and PRs were achieved significantly more frequently than in the TAE group. When the patients were divided into a responder group (CR, PR, and MR) and a nonresponder group (NC and PD), survival was significantly longer in the responder group. The findings of the present study suggest that the combination therapy was useful for improving the survival of patients with unresectable hepatocellular carcinoma.

Adult↗

Carboplatin/etoposide as first-line chemotherapy in advanced ovarian carcinoma: a pilot study.

In a pilot study, 18 patients with advanced ovarian cancer were evaluated for tolerance and response to a combination treatment with a fixed dose of carboplatin (350 mg/m2 given i.v. on day 1) and escalated doses of etoposide (70-130 mg/m2 daily given i.v. on days 1-3) as first-line chemotherapy. The maximum tolerated dose of etoposide was 130 mg/m2 when given i.v. on days 1-3 in combination with 350 mg/m2 carboplatin given i.v. every 4 weeks. At these dose levels, bone marrow toxicity was manageable and did not appear to be cumulative. In all, 12 objective responses, including 9 complete responses (CRs) and 3 partial responses (PRs), were achieved in 18 patients; 6 of the 9 CRs were confirmed as pathological CRs by second-look surgery.

Aged↗