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Abstract
Serum immunoglobulin E (IgE) and absolute eosinophil count (AEC) were assayed in 48 children with idiopathic nephrotic syndrome and 20 controls. The mean serum IgE (p < 0.001) and AEC (p < 0.05) were significantly raised in active nephrotic syndrome compared with controls. The mean values of IgE and AEC in nephrotic patients were 228.6 and 164.5 per cent of the normal mean, respectively. The serum IgE and AEC were significantly abnormal in all the subgroups (first attack, infrequent, and frequent relapsers), except AEC in infrequent relapses, when compared with the controls. No significant differences in the parameters were observed among the different subgroups of cases. In remission, the mean IgE and AEC were unchanged in comparison with their corresponding values at diagnosis. Thus, the levels are raised not only in active but also in remission, reflecting abnormal immune status even in the disease-free state.
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152
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Ayers M, Symmans WF, Stec J, Damokosh AI, Clark E, Hess K, Lecocke M, Metivier J, Booser D, Ibrahim N, Valero V, Royce M, Arun B, Whitman G, Ross J, Sneige N, Hortobagyi GN, Pusztai L. Gene expression profiles predict complete pathologic response to neoadjuvant paclitaxel and fluorouracil, doxorubicin, and cyclophosphamide chemotherapy in breast cancer. J Clin Oncol 2004; 22:2284-93. [PMID: 15136595 DOI: 10.1200/jco.2004.05.166] [Citation(s) in RCA: 427] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
PURPOSE The goal of this study was to examine the feasibility of developing a multigene predictor of pathologic complete response (pCR) to sequential weekly paclitaxel and fluorouracil + doxorubicin + cyclophosphamide (T/FAC) neoadjuvant chemotherapy regimen for breast cancer. PATIENTS AND METHODS All patients underwent one-time pretreatment fine-needle aspiration to obtain RNA from the cancer for transcriptional profiling using cDNA arrays containing 30721 human sequence clones. Analysis was performed after profiling, and 42 patients' clinical results were available, 24 of which were used for predictive marker discovery; 18 patients' results were used as an independent validation set. RESULTS Thirty-one percent of patients had pCR (six discovery and seven validation), defined as disappearance of all invasive cancer in the breast after completion of chemotherapy. We could identify no single marker that was sufficiently associated with pCR to be used as an individual predictor. A multigene model with 74 markers (P <or=.09) was built using data from the discovery samples and tested on the validation samples. Overall, a 78% (14 of 18) predictive accuracy was observed, with a 100% (three of three) positive predictive value for pCR, a 73% (11 of 15) negative predictive value, a sensitivity of 43% (three of seven), and a specificity of 100% (11 of 11). The expected response rate to T/FAC neoadjuvant therapy in unselected patients is 28%. CONCLUSION Our results suggest that transcriptional profiling has the potential to identify a gene expression pattern in breast cancer that may lead to clinically useful predictors of pCR to T/FAC neoadjuvant therapy.
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Yahya A, Salleh F, Ibrahim N, Abd-Shukor R. Effects of Ti substitutions on superconductivity of TlSr-1212 ceramics. PHYSICA C: SUPERCONDUCTIVITY 2003; 388-389:371-372. [DOI: 10.1016/s0921-4534(02)02366-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
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154
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Kinrions P, Ibrahim N, Murphy K, Lehesjoki AE, Järvela I, Delanty N. Efficacy of levetiracetam in a patient with Unverricht-Lundborg progressive myoclonic epilepsy. Neurology 2003; 60:1394-5. [PMID: 12707458 DOI: 10.1212/01.wnl.0000058755.38892.80] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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155
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Ahmad A, Ibrahim N. Automated electrophoretic membrane cleaning for dead-end microfiltration and ultrafiltration. Sep Purif Technol 2002. [DOI: 10.1016/s1383-5866(02)00066-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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156
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Esmaeli B, Hortobagyi G, Esteva F, Valero V, Ahmadi MA, Booser D, Ibrahim N, Delpassand E, Arbuckle R. Canalicular stenosis secondary to weekly docetaxel: a potentially preventable side effect. Ann Oncol 2002; 13:218-21. [PMID: 11885997 DOI: 10.1093/annonc/mdf036] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND The purpose of this study was to describe canalicular stenosis as a mechanism for epiphora (excessive tearing) secondary to weekly docetaxel. PATIENTS AND METHODS Fourteen patients with metastatic breast cancer who developed epiphora during weekly docetaxel therapy underwent an ophthalmologic examination, and probing and irrigation of the nasolacrimal ducts. The total duration of docetaxel therapy, the duration of treatment at the time of onset of epiphora, the number of infusions, the cumulative dose of docetaxel and the severity of canalicular stenosis were recorded. RESULTS All 14 patients had anatomic narrowing of the canaliculi as the underlying mechanism for epiphora. Bicanalicular silicone intubation or dacryocystorhinostomy (DCR) was recommended for all 14 patients. Eleven patients underwent surgery and experienced resolution of their symptoms. The three patients who declined surgery continue to have epiphora at the time of this report. CONCLUSIONS Canalicular stenosis is an underlying mechanism for epiphora in patients receiving weekly docetaxel. Bicanalicular silicone intubation should be considered early in the course of weekly docetaxel therapy to prevent complete closure of the canaliculi. Once complete or near complete stenosis of the canaliculi occurs, DCR with a permanent pyrex glass tube placement may become necessary to overcome the blockage of tear outflow.
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157
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Shibuya I, Setiadji SV, Ibrahim N, Harayama N, Maruyama T, Ueta Y, Yamashita H. Involvement of postsynaptic EP4 and presynaptic EP3 receptors in actions of prostaglandin E2 in rat supraoptic neurones. J Neuroendocrinol 2002; 14:64-72. [PMID: 11903814 DOI: 10.1046/j.1365-2826.2002.00741.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We have reported that supraoptic nucleus (SON) neurones are excited by prostaglandin E2 (PGE2) presumably via dual postsynaptic PG receptors, FP receptors and unidentified EP receptors, and that presynaptic EP receptors may also be involved in the excitation. In the present study, to clarify the receptor mechanism of the PGE2-mediated actions on SON neurones, we studied the pre- and postsynaptic effects of four newly developed EP agonists that are selective for each of the four EP receptors, EP1-4, on rat SON neurones using extracellular recording and whole-cell patch-clamp techniques. The EP4 agonist ONO-AE1-329 mimicked the excitatory effects of PGE2, whereas the EP1 agonist ONO-DI-004, the EP2 agonist ONO-AE1-257 and the EP3 agonist ONO-AE-248 had little or no effect. The effects of ONO-AE1-329 were unaffected by the EP1/FP/TP antagonist, ONO-NT-012, which potently suppressed the excitation caused by the FP agonist fluprostenol and PGE2. ONO-AE1-329 caused marked excitation when responses to fluprostenol were desensitized by repeated applications of fluprostenol. Patch-clamp analysis in SON neurones showed that ONO-AE1-329 induced inward currents at a holding potential of -70 mV and the reversal potential of the currents was -35.1 +/- 2.3 mV. On the other hand, the frequency of spontaneous inhibitory postsynaptic currents recorded from SON slice preparations was suppressed by ONO-AE-248, but unaffected by the other three EP agonists. These results suggest that SON neurones possess postsynaptic EP4 receptors and that gamma-aminobutyric acid neurones innervating SON neurones possess presynaptic EP3 receptors in their terminals. Activation of the two EP receptors may be involved in the excitatory regulation of SON neurones by PGE2.
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MESH Headings
- Animals
- Dinoprostone/pharmacology
- Electrophysiology
- Extracellular Space/drug effects
- Extracellular Space/metabolism
- In Vitro Techniques
- Male
- Neurons/drug effects
- Patch-Clamp Techniques
- Prostaglandins F, Synthetic/pharmacology
- Rats
- Rats, Wistar
- Receptors, Presynaptic/drug effects
- Receptors, Presynaptic/physiology
- Receptors, Prostaglandin E/agonists
- Receptors, Prostaglandin E/antagonists & inhibitors
- Receptors, Prostaglandin E/drug effects
- Receptors, Prostaglandin E, EP3 Subtype
- Receptors, Prostaglandin E, EP4 Subtype
- Supraoptic Nucleus/cytology
- Supraoptic Nucleus/drug effects
- Supraoptic Nucleus/physiology
- Synapses/drug effects
- Synapses/metabolism
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158
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Cristofanilli M, Buzdar AU, Sneige N, Smith T, Wasaff B, Ibrahim N, Booser D, Rivera E, Murray JL, Valero V, Ueno N, Singletary ES, Hunt K, Strom E, McNeese M, Stelling C, Hortobagyi GN. Paclitaxel in the multimodality treatment for inflammatory breast carcinoma. Cancer 2001; 92:1775-82. [PMID: 11745249 DOI: 10.1002/1097-0142(20011001)92:7<1775::aid-cncr1693>3.0.co;2-e] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND Inflammatory breast carcinoma (IBC) is a rare but aggressive form of breast carcinoma. Anthracycline-based regimens represent the standard of treatment for IBC. Reports of significant clinical activity of paclitaxel in metastatic breast carcinoma led the authors to investigate the role of this drug in the management of IBC. METHODS Forty-four patients with IBC were enrolled between February 1994 and January 1998. The treatment plan consisted of induction chemotherapy (IC), mastectomy, adjuvant chemotherapy, and radiotherapy. Forty-two patients received IC with four cycles of fluorouracil, doxorubicin, and cyclophosphamide. If the clinical response was less than partial, patients were "crossed over" to paclitaxel before mastectomy. All patients received adjuvant paclitaxel. Patients unresectable after paclitaxel were offered high-dose chemotherapy with autologous peripheral blood progenitor cell support. RESULTS Thirty-four patients (81%) achieved an objective clinical remission; 3 patients (7%) achieved a clinical complete remission, 31 (74%) a partial remission. Six patients (14%) achieved pathologic complete remission. Sixteen patients were treated with paclitaxel, 7 of them (44%) were able to undergo mastectomy. Median time to progression (TTP) was 22 months. Median overall survival (OS) was 46 months. Concordance between clinical and pathologic response was documented in only 8 patients (24%). No differences in TTP and OS compared with a historical group of 178 IBC patients treated with anthracycline-based regimens. CONCLUSIONS Paclitaxel improves tumor resectability in anthracycline-refractory IBC. The impact of paclitaxel on the prognosis of IBC needs to be better evaluated in future trials using more dose-intensive schedules of administration. New imaging modalities may contribute to improve assessment of response to IC.
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159
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Pecora G, De Leonardis D, Ibrahim N, Bovi M, Cornelini R. The use of calcium sulphate in the surgical treatment of a 'through and through' periradicular lesion. Int Endod J 2001; 34:189-97. [PMID: 12193264 DOI: 10.1046/j.1365-2591.2001.00369.x] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AIM This randomized, controlled, clinical study was designed to evaluate the adjunctive effect of calcium sulphate grafts on the surgical treatment of through and through periradicular lesions. METHODOLOGY Twenty patients each with one tooth showing evidence radiologically of a periradicular lesion wider than 10 mm, with lack of both buccal and lingual cortical bony plates and an indication for surgery were selected for the study. Ten teeth were treated with apicectomy, root-end filling and grafting of the bone defect with calcium sulphate prior to suturing (test group). The other 10 teeth received the same surgical therapy but no grafting with calcium sulphate (control group). The outcome of the healing process was evaluated at 6 and 12 months radiographically following the criteria reported by Rud and Andreasen. RESULTS At the six- and 12-month evaluation the test group had seven teeth with complete healing and two with incomplete healing, whilst the control group showed three teeth with complete healing, five with incomplete healing and one with unsatisfactory healing. One tooth in each group had to be extracted because of a vertical fracture that occurred during the follow-up period. CONCLUSIONS The results of the study demonstrate that the addition of calcium sulphate as a bone graft during the conventional surgical treatment of through and through lesions improves the clinical outcome. Histological analysis is desirable to investigate the quality of tissues formed using the two surgical procedures.
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160
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Cristofanilli M, Fratarcangeli T, Esteva F, Rosales M, Booser D, Ibrahim N, Pusztai L, Bast R, Rivera E, Hortobagyi G. Weekly high-dose paclitaxel(HD-P) has significant antitumor activity in inflammatory breast cancer (IBC). Eur J Cancer 2001. [DOI: 10.1016/s0959-8049(01)81123-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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161
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Harrison GG, Galal OM, Ibrahim N, Khorshid A, Stormer A, Leslie J, Saleh NT. Underreporting of food intake by dietary recall is not universal: a comparison of data from egyptian and american women. J Nutr 2000; 130:2049-54. [PMID: 10917924 DOI: 10.1093/jn/130.8.2049] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Underreporting of dietary intake has been observed consistently in food consumption surveys in affluent societies and in clinical studies in a variety of settings. Almost one third of quantitative 24-h recalls provided by adults in U.S. surveys appear to result in estimates that are biologically implausible. Underreporting has been linked to obesity in both the U.S. and Europe, with heavier individuals underreporting to a greater degree than lean persons. A relative dearth of data exists from developing countries and those in transition to address the question whether such underreporting is universal. We present the first data from a large survey of women in a rapidly urbanizing developing country to address this question. More than 4500 adult women in Egypt provided quantitative 24-h recalls of food intake on the previous day in 1993-1994, and weights and heights were measured. We compared the data, in terms of the ratio of reported energy intake to estimated basal metabolic rate, to data from 3010 women in the 1994-1996 U.S. Continuing Survey of Food Intake by Individuals, on whom quantitative 24-h recalls were also conducted. The Egyptian women reported food intakes consistent with FAO/WHO recommendations for energy intakes for women of comparable activity levels, whereas the data for U.S. women showed underreporting consistent with other U.S. surveys. Only 10% of Egyptian women reported energy intakes below accepted criteria for plausibility, compared with one third of American women. We discuss possible reasons for this difference, including cultural and food supply differences, and methodological differences between the two surveys.
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162
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Shibuya I, Kabashima N, Ibrahim N, Setiadji SV, Ueta Y, Yamashita H. Pre- and postsynaptic modulation of the electrical activity of rat supraoptic neurones. Exp Physiol 2000; 85 Spec No:145S-151S. [PMID: 10795917 DOI: 10.1111/j.1469-445x.2000.tb00018.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The release of vasopressin and oxytocin is regulated by the electrical activity of magnocellular neurosecretory cells in the supraoptic and paraventricular nuclei, which is under the control of a great variety of neurotransmitters and neuromodulators. The major neural signals to the supraoptic nucleus are from excitatory glutamate inputs and inhibitory GABA inputs. In recent studies, the voltage-clamp mode of the whole-cell patch-clamp technique has been applied to slice preparations from rat hypothalamus to monitor synaptic inputs to supraoptic neurones. Spontaneous excitatory and inhibitory postsynaptic currents (EPSCs and IPSCs) are abolished by CNQX and picrotoxin, respectively, but are insensitive to tetrodotoxin, indicating that they represent quantal release of glutamate and GABA, respectively, from nerve terminals of presynaptic neurones. GABA and glutamate show remarkable suppressive effects on both EPSCs and IPSCs via presynaptic GABA(B) and mGlu receptors, respectively. Noradrenaline, which excites supraoptic neurones via postsynaptic alpha1-receptors, also suppresses IPSCs and potentiates EPSCs. On the other hand, prostaglandin E2, which excites supraoptic neurones via postsynaptic prostaglandin E2 (EP) receptors of the EP4 subclass, also suppresses IPSCs via EP3 receptors but has little effect on EPSCs. Thus pre- and postsynaptic mechanisms may act cooperatively to excite supraoptic neurones. Nitric oxide, which inhibits supraoptic neurones, potentiates IPSCs without affecting EPSCs. This provides another example for the preferential modulation of IPSCs of supraoptic neurones. On the other hand, PACAP, which causes a long-lasting increase in the firing frequency via the postsynaptic receptors, has no effect on EPSCs and IPSCs, suggesting that some ligands act only at postsynaptic receptors. Thus multiple patterns for pre- and postsynaptic modulation are present in the supraoptic nucleus, and the electrical activity of supraoptic neurones is regulated via complex mechanisms at both pre- and postsynaptic sites.
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163
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El-Shafei HA, Abd-El-Sabour H, Ibrahim N, Mostafa YA. Isolation, screening and characterization of bacteriocin-producing lactic acid bacteria isolated from traditional fermented food. Microbiol Res 2000; 154:321-31. [PMID: 10772154 DOI: 10.1016/s0944-5013(00)80006-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
100 lactic acid bacterial strains isolated from traditional fermented foods (yoghurt, milk cream, sour dough and milk) were screened for bacteriocin production. Twenty six strains producing a nisin-like bacteriocin were selected. Most of these isolates gave only a narrow inhibitory spectrum, although one showed a broad inhibitory spectrum against the indicator strains tested, this strain was determined as Lactococcus lactis. The influence of several parameters on the fermentative production of nisin by Lactococcus lactis was studied. Production of nisin was optimal at 30 degrees C and in the pH range 5.5-6.3. The effect of different sulphur and nitrogen sources on Lactococcus lactis growth and nisin production was studied. Magnesium sulfate and manganese sulfate were found to be the best sulphur sources while triammonium citrate was the best inorganic nitrogen source and meat extract, peptone and yeast extract were the best organic nitrogen source for nisin production.
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164
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Fulton TR, Ibrahim N, Losada MC, Grzegorski D, Tkacz JS. A melanin polyketide synthase (PKS) gene from Nodulisporium sp. that shows homology to the pks1 gene of Colletotrichum lagenarium. MOLECULAR & GENERAL GENETICS : MGG 1999; 262:714-20. [PMID: 10628853 DOI: 10.1007/s004380051133] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The melanin polyketide synthase (pks) gene of Nodulisporium sp. MF5954 (ATCC74245) was cloned by exploiting its homology to the Colletotrichum lagenarium pks1 gene. Sequence analysis demonstrated that this gene is 70% identical to the C. lagenarium pks1 gene. A gene disruption construct, designed to replace both the ketoacyl synthase and acyl transferase domains with a hygromycin resistance (Hyr) gene, was synthesized, and used to disrupt the Nodulisporium melanin pks1 gene via homologous recombination, resulting in a mel(-) phenotype. Sequence analyses of the gene and of cDNA segments generated by RT-PCR indicate that there are three introns in the 5' half of the gene. The proposed 2159-amino acid product is 72% identical and 78% similar to the 2187-amino acid sequence deduced from the C. lagenarium pks1 gene. This similarity is notable, considering that C. lagenarium is a member of the order Phyllachoales or Sordariales, whereas Nodulisporium is generally believed to be member of the order Xylariales. However, despite the strong resemblance between the amino acid sequences in the acyl transferase domains of the two proteins, only one in five codons are conserved in the DNA sequences that encode this motif. The Nodulisporium sp. pks1 gene sequence and the amino acid sequence deduced from its coding region have been deposited in Genbank under Accession No. AF151533.
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165
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Buzdar AU, Singletary SE, Theriault RL, Booser DJ, Valero V, Ibrahim N, Smith TL, Asmar L, Frye D, Manuel N, Kau SW, McNeese M, Strom E, Hunt K, Ames F, Hortobagyi GN. Prospective evaluation of paclitaxel versus combination chemotherapy with fluorouracil, doxorubicin, and cyclophosphamide as neoadjuvant therapy in patients with operable breast cancer. J Clin Oncol 1999; 17:3412-7. [PMID: 10550135 DOI: 10.1200/jco.1999.17.11.3412] [Citation(s) in RCA: 173] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
PURPOSE To compare prospectively the antitumor activity of single-agent paclitaxel to the three-drug combination of fluorouracil, doxorubicin, and cyclophosphamide (FAC) as neoadjuvant therapy in patients with operable breast cancer. PATIENTS AND METHODS Patients with T1-3N0-1M0 disease were randomized to receive either paclitaxel (250 mg/m(2)) as 24-hour infusion or FAC in standard doses at every-3-week intervals. Each patient was treated with four cycles of preoperative chemotherapy. Clinical response and extent of residual disease in the breast and lymph nodes was assessed after four cycles of induction chemotherapy. RESULTS A total of 174 patients were registered, and 87 were randomized to each arm of the study. Clinical response, ie, complete and partial responses, was similar in both arms of the study. Three patients in the FAC arm and one patient in the paclitaxel subgroup had progressive disease. The extent of residual disease by intent-to-treat analysis at the time of surgery was similar between the two arms of the study. CONCLUSION The results of this prospective study demonstrated that single-agent paclitaxel as neoadjuvant therapy has significant antitumor activity, and this was clinically comparable to FAC. Similar fractions of patients had clinical complete and partial responses, and very few patients had no response to either therapy. The value of alternate non-cross-resistant therapies as used in this protocol on the clinical course of this disease would require longer follow-up.
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166
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Ibrahim N, Shibuya I, Kabashima N, Sutarmo SV, Ueta Y, Yamashita H. Prostaglandin E2 inhibits spontaneous inhibitory postsynaptic currents in rat supraoptic neurones via presynaptic EP receptors. J Neuroendocrinol 1999; 11:879-86. [PMID: 10520139 DOI: 10.1046/j.1365-2826.1999.00404.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Prostaglandin E2 (PGE2) has been implicated in the excitatory regulation of magnocellular neurones in the supraoptic nucleus (SON). We have recently reported that PGE2 excited SON neurones by directly activating postsynaptic PGE2 receptors (EP receptors) of a subclass other than EP1-3, but did not affect excitatory postsynaptic currents (EPSCs). In the present study, we examined presynaptic effects of PGE2 on rat SON neurones by measuring spontaneous inhibitory postsynaptic currents (IPSCs) by a slice patch-clamp technique. PGE2 inhibited spontaneous IPSCs in a dose-dependent and reversible manner. PGE2 selectively suppressed the frequency of IPSCs without affecting the amplitude of IPSCs in the presence of tetrodotoxin, a blocker of Na+ channels, indicating that the effects were presynaptic. The inhibitory effects of PGE2 on the frequency of IPSCs were mimicked by the EP1/EP3 agonists, 17PT-PGE2 and sulprostone, and the EP2/EP3 agonist, misoprostol, whereas the EP2 agonist, butaprost, or the FP agonist, fluprostenol, had little effect. The effects of PGE2 on IPSCs were unaffected by the selective EP1 antagonist, SC-51322. They were unaffected also by antagonists of GABAB and alpha2 adrenergic receptors, which are present at presynaptic terminals of GABA neurones in the SON and cause suppression of spontaneous IPSCs. The inhibitor of PG synthesis, indomethacin, had little effect on spontaneous IPSCs and on the inhibitory effects of PGE2 as well as of the GABAB agonist, baclofen, and noradrenaline. These results suggest that PGE2 inhibits release of GABA from the GABAergic terminals innervating SON neurones by activating presynaptic EP receptors, presumably of the EP3 subclass, and that such a presynaptic mechanism may play a role in the excitatory regulation of SON neurones by PGE2.
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167
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House WJ, Ibrahim N. Fertility patterns of adolescent and older women in Pacific Island countries: programme implications. ASIA-PACIFIC POPULATION JOURNAL 1999; 14:3-22. [PMID: 12349401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
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168
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Sutarmo Setiadji V, Shibuya I, Kabashima N, Ibrahim N, Harayama N, Ueta Y, Yamashita H. Actions of prostaglandin E2 on rat supraoptic neurones. J Neuroendocrinol 1998; 10:927-36. [PMID: 9870750 DOI: 10.1046/j.1365-2826.1998.00282.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Prostaglandins (PGs) have been implicated in the regulation of vasopressin (VP) and oxytocin (OT) release in response to various stimuli. To examine the site and mechanism of actions of PGs, we studied effects of PGE2 and PG-receptor agonists on supraoptic nucleus (SON) neurones of rat hypothalamic slice preparations using extracellular recording and whole-cell patch-clamp techniques. PGE2 modulated the electrical activity of more than 80% of the neurones studied. The effects of PGE2 on both phasic and non-phasic neurones were mostly excitatory, and dose-dependent. The effects of PGE2 were mimicked by PGF2alpha or the FP agonist, fluprostenol, whereas PGD2 or the selective EP, IP or TP agonist was less effective or had no effect. The effects of PGE2 were unaffected by the EP1 antagonist, SC-51322, but reduced to 80% of control by the EP1/FP/TP antagonist, ONO-NT-012, which reduced the effects of fluprostenol to 32% of control. Moreover, some neurones responsive to PGE2 did not respond to fluprostenol. Patch-clamp analysis in SON slice preparations revealed that PGE2 at 10(-6) M depolarized the membrane potential by 3.9+/-0.3 mV from the resting membrane potential of -58.4+/-2.2 mV in the current-clamp mode. In the voltage-clamp mode, PGE2 induced inward currents at a holding potential of -70 or -80 mV, while it did not affect spontaneous excitatory postsynaptic currents. PGE2 induced currents also in dissociated SON neurones and the reversal potential of the currents was -35.5+/-0.9 mV, which was similar to that of currents induced by fluprostenol. These results suggest that SON neurones possess at least two types of PG receptors, FP receptors and EP receptors of a subclass different from EP1, EP2, or EP3, and that activation of these receptors leads to the opening of nonselective cation channels, membrane depolarization and increase of the action potential discharge.
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Le Chevalier T, Monnier A, Douillard JY, Ruffie P, Sun XS, Belli L, Ibrahim N, Bougon N, Bérille J. Docetaxel (Taxotere) plus cisplatin: an active and well-tolerated combination in patients with advanced non-small cell lung cancer. Eur J Cancer 1998; 34:2032-6. [PMID: 10070306 DOI: 10.1016/s0959-8049(98)00287-1] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The activity of the combination of intravenous docetaxel 75 mg/m2 plus cisplatin 100 mg/m2 administered every 3 weeks for 3 cycles then every 6 weeks was investigated in 51 chemotherapy naive patients with locally advanced or metastatic non-small cell lung cancer (NSCLC). The population was 92% male, with a median age of 54 years and median performance status of 1; 80% of patients had metastatic disease, including 37% with bone involvement. All patients received prophylactic premedication (ondansetron, dexamethasone plus cetirizine) and standard hyperhydration. With a median of 4 treatment cycles (range 1-9), 14 of 42 evaluable patients responded (overall response rate 33.3%, 95% CI 19.6-49.6%); the median response duration was 7.3 months, median survival 8.4 months, and 1-year survival rate 35%. The most common adverse event was neutropenia, occurring in two-thirds of patients. Neurosensory effects were cumulative but generally mild. No treatment-related deaths occurred. This combination of docetaxel/cisplatin showed activity in advanced NSCLC. While it was not clearly superior to single-agent docetaxel, due to differences in prognostic factors among the patients in open trials, a randomised study would be needed to demonstrate definitively whether cisplatin adds to the activity of docetaxel or not.
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Ibrahim N, Shibuya I, Kabashima N, Setiadji VS, Ueta Y, Yamashita H. GABAB receptor-mediated inhibition of spontaneous action potential discharge in rat supraoptic neurons in vitro. Brain Res 1998; 813:88-96. [PMID: 9824676 DOI: 10.1016/s0006-8993(98)01009-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
To elucidate the role of GABAB receptors in the regulation of the electrical activity of magnocellular neurons of the supraoptic nucleus (SON), the effects of GABAB agonist and antagonist on the firing rate of spontaneous action potentials were studied in SON slice preparations of rats by extracellular recordings. In the presence of the gamma-amino butyric acid (GABA)-gated chloride channel blocker, picrotoxin, the selective GABAB agonist, baclofen, reduced the firing rate of action potentials in both phasic and non-phasic neurons in a dose-dependent manner. The reduction in the firing rate induced by baclofen was reversed by the selective GABAB antagonist, 2-hydroxy saclofen (2OH-saclofen), also in a dose-dependent manner. In non-phasic neurons, 2OH-saclofen significantly increased the firing rate and the effect was additive to the effect of picrotoxin. In phasic neurons, 2OH-saclofen alone did not increase the firing rate, but it reversed suppression of the firing induced by increasing extracellular Ca2+ concentration to 2.1 mM. Baclofen also reduced the firing rate of non-phasic neurons of virgin and lactating female rats, indicating that the GABAB receptor-mediated inhibition is not confined to SON neurons of male rats. The evidence indicates that activation of GABAB receptors inhibits electrical activity of SON neurons of both male and female rats and that GABAB receptors may play an important role in the inhibitory regulation of the electrical activity of SON neurons by GABA.
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Ibrahim N. Determination of Natural Radioactivity in Fertilizers by Gamma Ray Spectroscopy. Radiat Phys Chem Oxf Engl 1993 1998. [DOI: 10.1016/s0969-806x(97)00222-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Yu D, Liu B, Jing T, Sun D, Price JE, Singletary SE, Ibrahim N, Hortobagyi GN, Hung MC. Overexpression of both p185c-erbB2 and p170mdr-1 renders breast cancer cells highly resistant to taxol. Oncogene 1998; 16:2087-94. [PMID: 9572489 DOI: 10.1038/sj.onc.1201729] [Citation(s) in RCA: 95] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
We recently found that overexpression of p185c-erbB2 in c-erbB2 transfected MDA-MB-435 breast cancer cells (435.eB transfectants) confers a 5-9-fold increase in Taxol resistance. To examine whether Taxol resistance is a common phenomenon in other c-erbB2 overexpressing breast cancer cell lines, we tested a panel of human breast cancer cell lines established from different patients and expressing pl85c-erbB2 at different levels for their sensitivity to Taxol and Taxotere, a synthetic taxoid. Higher expression of p185c-erbB2 in these breast cancer cell lines indeed correlated well with resistance to Taxol and Taxotere, and the degree of resistance was about 100-fold that in c-erbB2-overexpressing 435.eB transfectants, demonstrating that these breast cancer cells are highly resistant to Taxol. Since mdr-1-encoded p-glycoprotein (p170mdr-1) has been implicated in Taxol resistance, we next examined the p170mdr-1 levels in these breast cancer cell lines that are highly resistant to Taxol. Higher levels of p170mdr-1 expression were found in several breast cancer cell lines that are highly resistant to Taxol. Since these same breast cancer cell lines also expressed higher levels of p185c-erbB2, we sought to determine the relative contribution of p185c-erbB2 and p170mdr-1 overexpression to Taxol resistance. We first specifically down-regulated cell surface p185c-erbB2 using anti-p185c-erbB2 monoclonal antibodies and assayed sensitivity of these cells to Taxol. We next specifically inactivated p170mdr-1 function using p170mdr-1 blockers (thioridazine or verapamil) and again assayed Taxol sensitivity. Both p185c-erbB2 down-regulation and p170mdr-1 blockade significantly sensitized the breast cancer cell lines to Taxol. The results indicate that overexpression of either p185c-erbB2 or p170mdr-1 renders human breast cancer cells resistant to Taxol. Furthermore, p185c-erbB2 synergizes with p170mdr-1 conferring higher degrees of Taxol resistance. Finally, combination therapy (down-regulation of p185c-erbB2 plus blocking p170mdr-1 plus administration of Taxol) may be beneficial to breast cancer patients whose tumors express high levels of both p185c-erbB2 and p170mdr-1.
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Ahmed F, Vyas V, Saleem A, Li XG, Zamek R, Cornfield A, Haluska P, Ibrahim N, Rubin EH, Gupta E. High-performance liquid chromatographic quantitation of total and lactone 20(S)camptothecin in patients receiving oral 20(S)camptothecin. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 1998; 707:227-33. [PMID: 9613954 DOI: 10.1016/s0378-4347(97)00615-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
We have developed a sensitive high-performance liquid chromatography (HPLC) assay to quantitate total and lactone forms of 20(S)camptothecin (CPT) in human plasma. Lactone and total CPT were extracted using solid-phase extraction and liquid-liquid extraction, respectively. The extracted lactone samples could be stored without immediate HPLC analysis. The two forms of CPT were quantitated by reversed-phase HPLC with fluorescence detection. The extraction efficiencies were about 100% and 92% for the total and lactone forms, respectively. The lower limit of quantitation was 5.74 nM for the two forms. The method was reproducible with a mean interday and intraday variability of 6% for total CPT and 4% and 6%. respectively, for lactone CPT. The assay could effectively quantitate lactone and total CPT in patients receiving single dose and multiple doses of oral CPT.
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Abstract
BACKGROUND The authors reviewed the incidence of toxic skin reactions in patients with metastatic breast carcinoma (MBC) treated with vinorelbine as a continuous infusion. METHODS A Phase I/II protocol was designed in which vinorelbine was given as an 8-mg intravenous bolus followed by a 96-hour CI of 7-14 mg/m2/day. Sixty patients were enrolled in the study: all had MBC and had received prior chemotherapy, and they had no known dermatologic disorder. RESULTS Hand-foot syndrome (HFS) developed in 4 of the 60 patients. Patient 1 started with vinorelbine at 12 mg/m2/day. She developed typical HFS. In the second course, her dose was decreased to 11 mg/m2/day, but again she experienced HFS. In the third course, dexamethasone was added to the regimen, and no HFS was observed in the remaining six courses. Patient 2 started with a dose of 9 mg/m2/ day. She received four courses without complications; but when the vinorelbine dose was escalated to 10 mg/m2/day, HFS developed. Patient 3 started with a vinorelbine dose of 14 mg/m2/day. She developed mucositis during the first two courses and HFS during the third. Patient 4 received vinorelbine at a dose of 13 mg/m2/day and developed significant HFS. All patients had complete dermatologic recovery. No toxic skin reactions were observed in 14 patients receiving vinorelbine doses of <10 mg/m2/day, whereas 4 of 46 treated at 10-14 mg/m2/day developed HFS, suggesting a relationship of dose to HFS occurrence. CONCLUSIONS Longer infusions of vinorelbine are occasionally associated with HFS. The pathophysiology is not completely clear, but a relationship of HFS occurrence to dose is suggested. Steroids were effective as prophylaxis in one patient.
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Ibrahim N, Fujita H, Hara T, Endo T. Automated detection of clustered microcalcifications on mammograms: CAD system application to MIAS database. Phys Med Biol 1997; 42:2577-89. [PMID: 9434310 DOI: 10.1088/0031-9155/42/12/021] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
To investigate the detection performance of our automated detection scheme for clustered microcalcifications on mammograms, we applied our computer-aided diagnosis (CAD) system to the database of the Mammographic Image Analysis Society (MIAS) in the UK. Forty-three mammograms from this database were used in this study. In our scheme, the breast regions were firstly extracted by determining the skinline. Histograms of the original images were used to extract the high-density area within the breast region as the segmentation from the fatty area around the skinline. Then the contrast correction technique was employed. Gradient vectors of the image density were calculated on the contrast corrected images. To extract the specific features of the pattern of the microcalcifications, triple-ring filter analysis was employed. A variable-ring filter was used for more accurate detection after the triple-ring filter. The features of the detected candidate areas were then characterized by feature analysis. The areas which satisfied the characteristics and specific terms were classified and displayed as clusters. As a result, the sensitivity was 95.8% with the false-positive rate at 1.8 clusters per image. This demonstrates that the automated detection of clustered microcalcifications in our CAD system is reliable as an aid to radiologists.
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