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Yamada M, Sumazaki R, Adachi H, Ahmed T, Matsubara T, Hori T, Nakahara A, Takita H. Resolution of protein-losing hypertrophic gastropathy by eradication of Helicobacter pylori. Eur J Pediatr 1997; 156:182-5. [PMID: 9083755 DOI: 10.1007/s004310050578] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
UNLABELLED There is as yet no consensus about the need for treatment of Helicobacter pylori infections, except for H. pylori-associated peptic ulcer. We present a 3-year-old boy with a 3-month history of oedema and hypoproteinaemia associated with hypertrophic gastropathy. Abdominal scintigram using intravenous 99mTc-labelled human serum albumin scintigraphy and direct measurement of protein in gastric juice proved that serum proteins were massively secreted in the stomach. Histological findings of mucosal inflammation were observed and H. pylori was isolated from the gastric mucosa. The protein loss promptly stopped within 2 weeks of the beginning of eradication therapy. CONCLUSION Protein-losing hypertrophic gastropathy may be induced by Helicobacter pylori-associated gastritis and should therefore be carefully evaluated by histological and bacteriological examination to provide a basis for eradication of H. pylori.
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Ahmed T, Lake DE, Beer M, Feldman EJ, Preti RA, Seiter K, Helson L, Mittelman A, Kancherla R, Ascensao J, Akhtar T, Cook P, Goldberg R, Coleman M. Single and double autotransplants for relapsing/refractory Hodgkin's disease: results of two consecutive trials. Bone Marrow Transplant 1997; 19:449-54. [PMID: 9052910 DOI: 10.1038/sj.bmt.1700682] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
To evaluate a strategy of one cycle of dose-intensive chemotherapy for patients with Hodgkin's disease in sensitive relapse and two cycles for those with refractory disease, 122 patients received dose-intensive chemotherapy followed by autotransplant in two consecutive studies. Patients with refractory disease were offered a second transplant with different conditioning in the absence of progression or excessive toxicity. CR was present after treatment in 46% while 16% died in the peritransplant period. Of 41 patients with primary refractory disease and 42 with refractory relapse, 24 and 21 respectively received a second cycle. Of these 45 refractory patients, 12 were in CR and 11 in PR after the first cycle and 10 of these 11 in PR achieved a durable CR with the second transplant. The CR rate is 37% in patients with refractory relapse and 19% in those with primary refractory disease. At a median follow-up of 4 years, median survival is 45 months. Progression-free survival of the refractory patients who could receive a second cycle was similar to that of patients with sensitive disease. A sequential transplant strategy is feasible. A subgroup of patients with refractory disease can achieve long-term survival after sequential BMT.
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228
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Farley TJ, Ahmed T, Fitzgerald M, Preti RA. Optimization of CD34+ cell selection using immunomagnetic beads: implications for use in cryopreserved peripheral blood stem cell collections. JOURNAL OF HEMATOTHERAPY 1997; 6:53-60. [PMID: 9112218 DOI: 10.1089/scd.1.1997.6.53] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Isolation of CD34+ cells from bone marrow, umbilical cord blood, and mobilized peripheral blood stem cell (PBSC) collections has many potential clinical benefits. The aim of this study was to evaluate the use of the ISOLEX 300 system to select hematopoietic precursors and determine the effectiveness at depleting contaminating tumor cells from cryopreserved/thawed PBSC. Median recovery of CD34+ cells and CFU-GM colonies was 71% and 51.5%, respectively, using a protocol optimized for our laboratory. A mean 2.9 log10 decrease in contaminating breast carcinoma cells was seen after the selection process. Selected CD34+ cells underwent a second round of cryopreservation/thawing while retaining 85.6% viability and 72.3% recovery of CFU-GM colonies.
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Ahmed T, Kamota T, Sumazaki R, Shibasaki M, Hirano T, Takita H. Circulating antibodies to common food antigens in Japanese children with IDDM. Diabetes Care 1997; 20:74-6. [PMID: 9028698 DOI: 10.2337/diacare.20.1.74] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE To investigate the humoral immune response to common food antigens in Japanese children with IDDM. RESEARCH DESIGN AND METHODS IgG antibodies to cow's milk, beta-lactoglobulin, bovine serum albumin (BSA), alpha-lactalbumin, and hens egg ovalbumin were examined by enzyme-linked immunosorbent assay in the sera of 33 patients with IDDM, ages 11.8 +/- 3.4 years. The data were compared with that of 50 normal subjects, ages 10.3 +/- 5.1 years, who acted as control subjects. A positive antibody to a food antigen was defined as an antibody titer greater than the 95th percentile value in normal subjects. RESULTS Children with IDDM had significantly higher median titers of IgG antibodies to beta-lactoglobulin and ovalbumin (P = 0.03 and P = 0.0005 respectively). More children with IDDM than control subjects had positive IgG antibody to ovalbumin (21 vs. 6%, P = 0.04). Titers, as well as the number of positive antibodies to other food antigens, including BSA, did not differ between the two groups. CONCLUSIONS Japanese children with IDDM show an enhanced humoral immune response to beta-lactoglobulin and ovalbumin, a phenomenon that may be related to the pathogenesis of the disease.
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Obaid-ur-Rehman M, Ahmed T, Rehman S. The role of osmotic diuretics in the management of eclampsia in Karachi women. PAKISTAN JOURNAL OF PHARMACEUTICAL SCIENCES 1997; 10:39-45. [PMID: 16414791] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
In the present work, out of eighty (80) patients selected, suffering from eclampsia, thirty-five (35) were subjected to the combined therapy of diazepam (7-Chloro-1,3-dihydro-1-methyl-5-phenyl-2H-1, 4-benzo-diazepin-2-one) and mannitol (Osmotic diuretic) and forty-five (45) patients were administered diazepam only. Consequently it was inferred that osmotic diuretic (mannitol) exhibits beneficial effects on the management of eclampsia, thereby lowering the mortality and morbidity.
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Seiter K, Feldman EJ, Halicka HD, Traganos F, Darzynkiewicz Z, Lake D, Ahmed T. Phase I clinical and laboratory evaluation of topotecan and cytarabine in patients with acute leukemia. J Clin Oncol 1997; 15:44-51. [PMID: 8996123 DOI: 10.1200/jco.1997.15.1.44] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
PURPOSE To determine the maximal-tolerated dose (MTD) of topotecan with cytarabine in acute leukemia patients, and to evaluate leukemia cell apoptosis in these patients. PATIENTS AND METHODS Fifty-three patients with acute leukemia not responsive to standard therapy were treated at eight dose levels of topotecan (2.5 mg/m2/d to 7.75 mg/m2/d). Topotecan was given as a 30-minute infusion daily with cytarabine 1 g/m2/d, both for 5 days. Using a flow-cytometric technique, the percent apoptotic cells in blood and bone marrow samples was determined, and the cell cycle distribution of the leukemic cells studied. RESULTS Oropharyngeal mucositis was dose-limiting. The MTD of topotecan was 4.75 mg/m2/d for 5 days in high-risk patients and 7.0 mg/m2/d for 5 days in low-risk patients. The mean percent apoptotic cells in the peripheral blood reached a peak of 18.8%, a median of 48 hours following the first dose of topotecan. Patients with higher S-phase fractions, either before treatment or following cytarabine, were more likely to achieve bone marrow aplasia than those with lower S-phase fractions (P = .01 and P < .05, respectively). Clinical responses were seen in four of 39 patients with acute myelogenous leukemia (AML; of whom 32 had received prior high-dose cytarabine), three of six with acute lymphoblastic leukemia (ALL), and one of eight with chronic myelogenous leukemia in blast phase (CML-BP). CONCLUSION The recommended phase II dose of topotecan with intermediate-dose cytarabine is 4.75 mg/m2/d for high-risk patients and 7.0 mg/m2/d for low-risk patients. The percentage of cells in S phase was important in determining response to treatment.
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232
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Ahmed T, Kelly SM, Lawrence AJ, Mezna M, Price NC. Conformational changes associated with activation of bee venom phospholipase A2. J Biochem 1996; 120:1224-31. [PMID: 9010774 DOI: 10.1093/oxfordjournals.jbchem.a021545] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Bee venom PLA2 possesses a binding site for long-chain fatty acids that can be acylated by long-chain fatty acid imidazolides [Drainas, D. and Lawrence, A.J. (1978) Eur. J. Biochem. 91, 131-138]. Occupation of the site either by oleic acid or the oleoyl residue enhances the catalytic activity by 45.7-fold in the presence of 20% 1-propanol and occupation of the site by the oleoyl residue increases the lytic activity against rabbit erythrocytes by 60-fold. Treatment of the enzyme with oleic acid and glutaraldehyde is known to produce irreversible activation [Lawrence, A.J. and Moores, G.R. (1975) FEBS Lett. 49, 287-291]. Here we show that reduction of the glutaraldehyde-treated enzyme with borohydride stabilizes the activated state and enables the fatty acid to be removed, revealing that a large proportion of the induced activation does not require the presence of oleic acid and indicating that activation is due to a change in the conformation rather than the hydrophobicity of the protein. A kinetic study of enzyme activated by oleoyl imidazolide showed that this modification stabilizes the protein against reversible inactivation by 1-propanol. Comparison of the CD spectra of native and oleoyl imidazolide-activated enzyme shows a change in secondary structure with apparent increase in both alpha-helix and beta-sheet content. During reaction of the enzyme with oleoyl imidazolide, the protein fluorescence shows a biphasic response with an initial fall attributed to occupation of the binding site followed by a progressive decrease with a shift of the emission maximum from 341 to 348 nm. The rate of the second phase closely matched the rate of increase in catalytic activity of the enzyme. Free oleic acid caused a rapid fall in fluorescence emission without the subsequent slow change. These results support the proposal that oleic acid or the oleoyl residue occupy a very similar site on the protein and that occupation of this site increases the exposure of one or both of the Trp residues to the aqueous environment. Binding studies show that activation by oleoyl imidazolide does not increase the affinity of the enzyme for the erythrocyte membrane. It is proposed that occupation of a long-chain fatty acid binding site on the enzyme enhances catalytic activity by changing the conformation of the protein rather than acting as a hydrophobic anchor to the substrate surface.
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Ramu K, Perry CS, Ahmed T, Pakenham G, Kehrer JP. Studies on the basis for the toxicity of acrolein mercapturates. Toxicol Appl Pharmacol 1996; 140:487-98. [PMID: 8887466 DOI: 10.1006/taap.1996.0245] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Acrolein, 3-oxopropyl glutathione (oxoPrGSH), and S-3-hydroxypropyl N-acetylcysteine (hydroxyPrMCA) are confirmed metabolic products of cyclophosphamide. Other potential metabolites include the mercapturic acid S-3-oxopropyl N-acetylcysteine (oxoPrMCA), its sulfoxide, and their corresponding diacid forms. The reactivity of acrolein would appear to preclude its movement from the main site of formation (liver) to the sites of toxicity (lung and bladder). However, the rerelease of acrolein from various thiol conjugates via a beta-elimination reaction is possible. It is also possible that the parent conjugate is directly toxic. The current study examined the toxicity of various acrolein-thiol conjugates and related analogs to human lung adenoma A549 cells. The expected enhancement of acrolein, oxoPrMCA, and oxoPrMCA S-oxide toxicity (assessed as cell proliferation by the alamarBlue assay) following a 2-hr exposure of cells treated with diethyl maleate (DEM) to deplete GSH was observed. OxoPrGSH was toxic when present for 24 hr, and this toxicity was also enhanced by pretreatment with DEM. When treated with these conjugates alone, the depletion of intracellular GSH only occurred at doses above those needed to significantly inhibit cell proliferation. There were no changes in protein thiols as determined using the membrane impermeant fluorescent thiol probe para-sulfobenzoyloxybromobimane. The diacid conjugate was not toxic to A549 cells indicating further oxidation products of the mercapturic acids are not a factor in toxicity. ButanoneMCA, an analog of oxoPrMCA that cannot exist in the geminal diol form, inhibited A549 cell growth only slightly less effectively than oxoPrMCA, suggesting the geminal diol is not toxicologically significant. OxoBuMCA, which cannot undergo beta-elimination of acrolein, showed no toxicity to these cells, suggesting that the release of acrolein could be required. Exogenous GSH provided protection from all toxic compounds suggesting that the toxic species is electrophilic. Overall, the data suggest that toxicity, in terms of an inhibition of cell proliferation, is not due to the parent molecule but rather is the result of rereleased acrolein that then affects factors necessary for cell proliferation.
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Easaw SJ, Lake DE, Beer M, Seiter K, Feldman EJ, Ahmed T. Graft-versus-host disease. Possible higher risk for African American patients. Cancer 1996; 78:1492-7. [PMID: 8839556] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
BACKGROUND Race is not generally recognized as a factor in the severity or incidence of graft-versus-host disease (GVHD) after allogeneic bone marrow transplantation. The impression that African American patients had more frequent and severe GVHD prompted this retrospective survey. METHODS The records of 75 consecutive patients treated with a human leukocyte antigen-identical sibling bone marrow transplant from 1985 to 1993 were reviewed. GVHD prophylaxis uniformly employed cyclosporine and steroids. Treatment of GVHD included cyclosporine and high dose steroids in all cases. Antithymocyte globulin and other immunosuppressants were used in severe cases. RESULTS Of 75 patients, 56 (75%) were white, 11 (15%) were listed as "Hispanic", 7 (9%) were African Americans, and 1 was of Far-Eastern origin. Four of the African American patients had chronic myelogenous leukemia and 2 had acute leukemia, whereas 21 of the other 68 patients (31%) had chronic myelogenous leukemia, 31 (46%) had acute leukemia, and the remainder (33%) had miscellaneous hematologic malignancies. Transplants from a female donor to a male recipient were performed in 2 of 7 African Americans and 19 of 68 patients (28%) of other origins. Five of the 6 evaluable African American patients (83%; 95% confidence interval, 36-100%) had Grade 4 GVHD, as opposed to 5 of 61 patients of other racial origins (8%; 95% confidence interval, 3-18%). All African American patients died within 90 days of transplant. CONCLUSIONS Patients of African American origin possibly have a greater risk of GVHD.
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Ahmed T, D'Brot J, Abraham WM, Lucio J, Mendelssohn R, Robinson MJ, Shakir S, Sanpedro B. Heterogeneity of allergic airway responses in sheep: differences in signal transduction? Am J Respir Crit Care Med 1996; 154:843-9. [PMID: 8887573 DOI: 10.1164/ajrccm.154.4.8887573] [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: 02/02/2023] Open
Abstract
In preliminary studies we have observed that inhaled heparin blocks antigen-induced airway responses in sheep that develop only acute responses to inhaled antigen (acute responders), but not in sheep that develop both acute and later responses (dual responders). Because heparin is an antagonist of inositol triphosphate (IP3) (one of the pathways involved in stimulus-secretion-coupling in mast cells), the differential effect of inhaled heparin in acute responders and dual responders might indicate the involvement of different signaling pathways during IgE-mediated mast cell reactions. Therefore, in this study we compared the effects of heparin on antigen-induced bronchconstriction, allergic cutaneous reaction, and histamine release into bronchoalveolar lavage fluid (BAL) in sheep that develop only acute responses or dual responses to inhaled Ascaris suum antigen. Specific lung resistance (SRL) was measured in 21 sheep (eight acute responders; 13 dual responders) before and after inhalation challenge with antigen, without and after pretreatment with inhaled heparin (1,000 units/kg). Histamine in BAL was measured by RIA before and after segmental antigen challenge, without and after pretreatment with inhaled heparin (eight acute responders; eight dual responders). In acute responders, mean +/- SE SRL increased by 197 +/- 21% with antigen; this was prevented by inhaled heparin (deltaSRL = 15 +/- 7%; p < 0.05). In dual responders, inhaled heparin had no effect on antigen-induced early (deltaSRL = 328 +/- 51% versus 305 +/- 76%) or late (deltaSRL = 201 +/- 33% versus 163 +/- 15%) responses. After segmental antigen challenge, BAL mean +/- SE histamine increased from 2.09 +/- 0.8 nM to 75.4 +/- 21.1 nM in acute responders and 1.58 +/- 0.7 nM to 66.8 +/- 27.3 nM in dual responders (p < 0.01). Inhaled heparin inhibited the increase in BAL histamine by 81% in acute responders (p < 0.05) and by only 19% in dual responders (p = NS). As was seen in the airways, heparin attenuated the allergic cutaneous reaction in acute responders by 46% (p < 0.05), but it was ineffective in dual responders. In contrast, H-7, a nonspecific protein kinase C inhibitor, attenuated the cutaneous reaction in dual responders by 28% (p < 0.05), but it was ineffective in acute responders. These data suggest that heterogeneity of allergic airway response is related to difference in mast cell signal transduction; IP3 is the predominant second messenger in acute responders, whereas non-IP3 pathways may be involved in dual responders.
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Xu W, Seiter K, Feldman E, Ahmed T, Chiao JW. The differentiation and maturation mediator for human myeloid leukemia cells shares homology with neuroleukin or phosphoglucose isomerase. Blood 1996; 87:4502-6. [PMID: 8639816] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
The identity of the maturation inducer capable of mediating the differentiation of human myeloid leukemic HL-60 calls to terminal monocytic cells was investigated. One of such inducers from T cells was purified as a 54.3-kD peptide. The amino acid sequence of a tryptic peptide and the enzyme cleavage sites revealed 100% homology to neuroleukin or phosphoglucose isomerase (PGI). Neuroleukin mediates differentiation of neurons and is homologous to PGI, which catalyzes the interconversion of glucose-6-phosphate and fructose-6-phosphate. The 54.3-kD inducer was shown to have PGI enzymatic activity. Separately purified PGI by substrate-elution exhibited identical specificity as the maturation inducer for HL-60 cell differentiation. They mediated a reduction of proliferating S and G2M cells, and the mature monocytic calls acquired complement receptors, phagocytic capacity, and adherence morphology. The magnitude of differentiation was dosage dependent on the inducer, with a bell-shaped curve. At the excess dose range cells did not undergo differentiation and remained in a proliferating cycle. Abnormally elevated PGI enzyme activities were detected in the plasma of acute myelogenous leukemia patients. Whether they represent an excess of the differentiation regulator in patients and are important in leukemogenesis remain to be investigated.
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MESH Headings
- Aged
- Amino Acid Sequence
- Biological Factors/chemistry
- Biological Factors/isolation & purification
- Biological Factors/pharmacology
- Cell Differentiation/drug effects
- Cells, Cultured
- Culture Media, Conditioned/chemistry
- DNA, Complementary/genetics
- Glucose-6-Phosphate Isomerase/blood
- Glucose-6-Phosphate Isomerase/chemistry
- Glucose-6-Phosphate Isomerase/pharmacology
- HL-60 Cells/drug effects
- Humans
- Leukemia, Erythroblastic, Acute/enzymology
- Leukemia, Monocytic, Acute/enzymology
- Leukemia, Myeloid, Acute/enzymology
- Lymphocyte Activation/drug effects
- Male
- Middle Aged
- Molecular Sequence Data
- Molecular Weight
- Neoplasm Proteins/blood
- Phytohemagglutinins/pharmacology
- Sequence Homology, Amino Acid
- T-Lymphocytes/chemistry
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Abraham WM, Abraham MK, Ahmed T. Protective effect of heparin on immunologically induced tracheal smooth muscle contraction in vitro. Int Arch Allergy Immunol 1996; 110:79-84. [PMID: 8645983 DOI: 10.1159/000237315] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Our previous studies have shown that heparin, a competitive inhibitor of inositol triphosphate receptors, inhibits airway anaphylaxis in vivo. In the present study, we tested the hypothesis that heparin blocks immunologically induced tracheal smooth muscle (TSM) contraction in vitro. TSM was obtained from sheep allergic to Ascaris suum antigen, and was suspended in an organ bath containing oxygenated (95% O2, 5% CO2) Krebs-Henseleit buffer at 39 degrees C. After an equilibration period, the tissues were treated with heparin dissolved in 10 microliters DMSO, at concentrations of 1, 10, or 100 U/ml (final concentration in the bath). Two types of controls were used: vehicle (10 microliters DMSO)-treated tissues and tissues treated with the anti-asthmatic nedocromil sodium (10(-5) M). After 30 min pretreatment, tissues were challenged with 10, 30 and 100 microliters of antigen. Contractions induced by antigen were expressed as percentage of the contraction elicited by the maximum effective concentration of acetylcholine (ACh, 10(-2) M). Antigen produced dose-dependent increases in tension, which were blocked by heparin and nedocromil sodium; maximal inhibition was 43 and 52%, respectively. Neither heparin nor nedocromil sodium affected the dose-response curve or the maximum response to Ach. The addition of the heparin preservative (benzyl alcohol) did not reverse ACh-induced contractions, or inhibit antigen-induced contractile responses. These results suggest that heparin blocks immunologically induced TSM contraction, without affecting the contractile response to the airway smooth muscle agonist, ACh. This action of heparin is similar to that of the anti-asthmatic nedocromil sodium and may be related to inhibition of mast cell mediator release.
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Garrigo J, Danta I, Ahmed T. Time course of the protective effect of inhaled heparin on exercise-induced asthma. Am J Respir Crit Care Med 1996; 153:1702-7. [PMID: 8630624 DOI: 10.1164/ajrccm.153.5.8630624] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
We have previously shown that heparin attenuates allergic bronchoconstriction in sheep, inhibits anti-IgE mediated histamine release in isolated mast cells, and prevents the bronchoconstrictor response in subjects with exercise-induced asthma (EIA). The purpose of the present study was to determine the pharmacokinetics of anti-asthmatic activity of inhaled heparin in EIA and compare it with cromolyn sodium, a mast cell stabilizing agent with established efficacy in EIA. Nine subjects with a history of EIA were studied on 10 different experiment days. After obtaining baseline pulmonary functions on day 1, subjects performed a standardized exercise challenge to document the presence of EIA. While monitoring minute ventilation and heart rate, exercise challenge was performed on a treadmill with increasing workload, until 85% of predicted maximum heart rate was achieved. The subjects then continued the exercise at that workload for 10 min. EIA was assessed by measurements of specific airway conductance (SGaw) before and after exercise. On experiment days 2-10, the exercise challenge was performed after the subjects inhaled 4 ml of either heparin (20,000 u/ml), cromolyn (20 mg), or placebo solutions with increasing pretreatment intervals of 15 min, 1 h, 3 h, or 6 h in a single-blind, randomized fashion. Maximum decreases in SGaw (mean +/- SE) at 3 to 5 min after exercise on control (39 +/- 2.1%) and placebo (37 +/- 2.6%) days were reproducible. Heparin and cromolyn had no effect on baseline SGaw but attenuated the EIA in a time-dependent fashion. Heparin inhibited the bronchoconstrictor responses to exercise by 58%, 78%, and 67% (p < 0.05) when nebulized 15 min, 1 h and 3 h, respectively, before exercise; cromolyn attenuated the responses by 37%, 46%, and 41%, respectively, (p < 0.05). Although heparin offered greater protection than cromolyn (at 1 to 3 h), both agents were ineffective when administered 6 h before exercise. These data demonstrate that inhaled heparin prevents EIA for up to 3 h and is more effective than cromolyn.
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Carere RG, Webb JG, Ahmed T, Dodek AA. Initial experience using Prostar: a new device for percutaneous suture-mediated closure of arterial puncture sites. CATHETERIZATION AND CARDIOVASCULAR DIAGNOSIS 1996; 37:367-72. [PMID: 8721692 DOI: 10.1002/(sici)1097-0304(199604)37:4<367::aid-ccd5>3.0.co;2-9] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
A new device that enables closure of the femoral artery puncture site by percutaneous placement of two nonabsorbable sutures (Prostar) was evaluated. Our initial experience included 32 insertion attempts at 29 femoral arterial puncture sites and one femoral venous puncture site. The device was applied at arterial puncture sites that had been used to carry out 12 balloon angioplasties (41%), seven intracoronary stent placements (24%), five intraaortic balloon pump insertions (17%), four diagnostic angiographies (14%), and one rotational ablation (3%). The venous access site closed was in a patient who had undergone balloon angioplasty and intracoronary thrombolysis. Most patients were anticoagulated with an average activated clotting time (ACT) of 306 +/- 123 sec (12 patients) or an average PTT of 68 +/- 29 sec (14 patients). There were four failures to achieve hemostasis using the device due to: inability to place the device because of peripheral vascular disease, entrapment of cutaneous tissue in the suture, a suture break that prevented hemostasis from being achieved, and avulsion of the sutures from the needles. Although three other suture breaks occurred, these did not prevent hemostasis from being achieved. Thus, 88% (28/32) of attempted uses were successful, and by using a second device in two of the failed attempts, 94% (30/32) of the puncture sites were successfully closed using the device. There was one late rebleed that required 1 hr of groin clamp pressure in an angioplasty patient who had received intracoronary urokinase. An ooze of blood occurred in 4 patients, but in only 2 was this more than trivial, resulting in discontinuation of heparin in one patient and a small hematoma in the other. We conclude that this device can be used safely and effectively, even in fully anticoagulated patients who have undergone complex procedures. The ultimate role of the device will require further experience and appropriate randomized studies.
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Siddiqui A, Melamed MR, Abbi R, Ahmed T. Mucinous (colloid) carcinoma of urinary bladder following long-term cyclophosphamide therapy for Waldenstrom's macroglobulinemia. Am J Surg Pathol 1996; 20:500-4. [PMID: 8604819 DOI: 10.1097/00000478-199604000-00015] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Carcinoma of the urinary bladder is a known complication of cyclophosphamide therapy. Almost all such cases have been transitional cell carcinomas. We report here the second example of an adenocarcinoma of bladder and the first purely mucinous (colloid) carcinoma of urinary bladder developing after long-term cyclophosphamide therapy. The patient, a 77-year-old woman, had been treated for Waldenstrom's macroglobulinemia for at least 24 years, during which time treatment for this disease varied from 50 to 100 mg per day. The disease terminated in acute myelogenous leukemia, and she died of severe disseminated intravascular coagulopathy associated with hypermacroglobulinemia. The mucinous (colloid) carcinoma of the urinary bladder was an incidental finding at autopsy.
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Haq SA, Alam MN, Hossain SM, Dhar UK, Rahim S, Rahman M, Ahmed T, Tahir M. A study of prolonged pyrexia in Dhaka. BANGLADESH MEDICAL RESEARCH COUNCIL BULLETIN 1996; 22:33-42. [PMID: 9037843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
In a prospective study conducted in the Institute of Postgraduate Medicine & Research (IPGMR), Dhaka, 212 patients with prolonged pyrexia were thoroughly evaluated clinically and with the help of laboratory investigations with a view to reaching the diagnosis. Their clinical and laboratory data were recorded. Clinical features pertaining to a particular organ gave appropriate clue in 52% cases. Imaging techniques were instrumental in 24%, microbiological or serological investigations in 35%, invasive procedures were diagnostic in 42%, laparotomy had to be resorted to in five cases. Infectious diseases were the commonest causes of prolonged pyrexia accounting for about 63.21% of cases followed by neoplasms (12.74%) and connective tissue disorders (10.85%). Tuberculosis was the most common infection (24.53% of all cases) followed by enteric fever (12.74%) and visceral leishmaniasis (9.43%). Pleura was the commonest seat for tuberculosis followed by lymph nodes and abdomen. Leukemias were the commonest neoplasm and SLE the commonest connective tissue disorder presenting with prolonged fever. Several fundamental observations were made in the study. Infections are the commonest cause of prolonged fever in our community, neoplasms and connective tissue disorders are also not rare. Secondly, patients with temperature between 100 to 101 degrees F should not be denied evaluation with the apprehension of unnecessarily investigating for habitual hyperthermia, as the condition was distinctly rare in the series. Thirdly, analysis of materials from organs or systems suspected to be abnormal clinically or by simple imaging techniques had high diagnostic yield. Finally, usual causes of prolonged fever are illnesses ordinarily encountered in clinical practice, pyrexia becomes protracted either because the presentation is atypical or incomplete, or because we fail to make proper use of available clinical or paraclinical information.
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Feldman EJ, Seiter KP, Ahmed T, Baskind P, Arlin ZA. Homoharringtonine in patients with myelodysplastic syndrome (MDS) and MDS evolving to acute myeloid leukemia. Leukemia 1996; 10:40-2. [PMID: 8558935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Current anti-leukemic chemotherapy in patients with myelodysplastic syndromes (MDS) and MDS evolving to acute myeloid leukemia (AML) is associated with low response rates and high treatment-related toxicity. Homoharringtonine (HHT) is a novel cephalotaxime alkaloid with reported efficacy in relapsed and de novo AML and more recently, chronic myeloid leukemia. Although its mechanism(s) of action is not completely understood, in vitro studies have demonstrated both cytotoxic and differentiating activity in leukemic cells, as well as intra-cellular changes suggestive of apoptotic cell death. In a phase II trial, HHT was administered at a dose od 5 mg/m2 by 24-h continuous infusion daily for 9 days to patients with MDS and MDS evolving to AML (MDS/AML). Twenty-eight patients (MDS 16, MDS/AML 12) with a median age of 67 years (range 23-83) were entered. A complete remission was achieved in seven patients, a partial remission was achieved in one patient for an overall response rate of 28% (8/28). There were four of 13 responders in MDS/AML patients and four of 15 in patients with MDS. The median duration of complete response was 7 months (range 2-10). Significant myelosuppression was universal and resulted in a high incidence of induction deaths (13/28) due to neutropenic-related infections. Extramedullary toxicity was mild and consisted of hypo-tension, fluid retention, hypoglycemia, diarrhea, nausea and vomiting. HHT given in this dose and schedule demonstrated limited activity in MDS and MDS/AML and was associated with prolonged pancytopenia and marrow hypoplasia in many patients. Administration of HHT at a lower dose or in combination with hematopoietic growth factors may lead to better results, but treatment with HHT as single agent at this dose and schedule is not currently recommended for these patients.
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Ahmed T, Lake D, Feldman E, Seiter K, Helson L, Mittelman A, Puccio C, Chun H, Grima K, Akhtar T. Factors influencing prognosis after dose-intensive therapy for recurrent or refractory Hodgkin's disease. Results of sequential trials: a case for treating patients with resistant disease. Ann N Y Acad Sci 1995; 770:305-14. [PMID: 8597368 DOI: 10.1111/j.1749-6632.1995.tb31063.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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244
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Seiter K, Feldman EJ, Traganos F, Li X, Halicka HD, Darzynkiewicz Z, Lederman CA, Romero MB, Ahmed T. Evaluation of in vivo induction of apoptosis in patients with acute leukemia treated on a phase I study of paclitaxel. Leukemia 1995; 9:1961-6. [PMID: 7475290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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245
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Ahmed T, Silagy C. The move towards evidence-based medicine. Med J Aust 1995; 163:60-1. [PMID: 7616896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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246
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Rahman MO, Ahmed T. An analysis of serum estradiol and serum progesterone in postmenopausal women of karachi suffering from breast cancer. PAKISTAN JOURNAL OF PHARMACEUTICAL SCIENCES 1995; 8:39-45. [PMID: 16420999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
The cancer patients (39) and control (12) were subjected to postmenopausal hormonal evaluation in which serum estradiol and serum progesterone values were found to be 54.56 +/- 10.20 pg/ml as compared to 18.66 +/- 6.31 pg/ml and 0.170 +/- 0.01 ng/ml as compared to 0.229 +/- 0.01 ng/ml respectively. Consequently it was inferred that in cancer postmenopausal patients when serum estradiol level increases the serum progesterone level decrease and vice versa.
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Ramu K, Fraiser LH, Mamiya B, Ahmed T, Kehrer JP. Acrolein mercapturates: synthesis, characterization, and assessment of their role in the bladder toxicity of cyclophosphamide. Chem Res Toxicol 1995; 8:515-24. [PMID: 7548731 DOI: 10.1021/tx00046a005] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Acrolein is the metabolite of cyclophosphamide (CP) believed to be involved in the bladder toxicity associated with this anticancer drug. The mechanism by which this extremely reactive intermediate is delivered to the bladder is not known. Glutathione (GSH) readily conjugates with acrolein, and the acrolein mercapturate S-(3-hydroxypropyl)-N-acetylcysteine (3-hydroxy-PrMCA) has been found in the urine of animals and man given CP. The objectives of this study were to prepare and characterize synthetic standards of the GSH acrolein adduct (3-oxopropyl)glutathione (3-oxoPrGSH), the acrolein mercapturates S-(3-oxopropyl)-N-acetylcysteine (3-oxoPrMCA) and 3-hydroxyPrMCA, and the S-oxidation product of 3-oxoPrMCA (3-oxoPrMCA S-oxide). In addition, the release of acrolein from, and the bladder toxicity of, these conjugates was determined. 3-OxoPrGSH and 3-oxoPrMCA were prepared with a 99% yield by condensing acrolein with GSH and N-acetylcysteine, respectively. 3-HydroxyPrMCA was prepared with a 63% yield by refluxing 3-chloropropanol and N-acetylcysteine in a basic medium. Oxidation of 3-oxoPrMCA with H2O2 was used to prepare 3-oxoPrMCA S-oxide. By decreasing the reaction time to 1 h, and adjusting the ratio of 3-oxoPrMCA to H2O2, the yield of 3-oxoPrMCA S-oxide was increased to 96%. The anhydrous aldehyde, 3-oxoPrMCA, afforded characteristic aldehydic proton resonances (1H NMR) in deuterated dimethyl sulfoxide. New resonances were observed in deuterated water, indicating a 75% hydration of the aldehyde to the corresponding geminal diol. This phenomenon was enhanced with 3-oxoPrMCA S-oxide where approximately 100% hydration of the aldehyde to the corresponding geminal diol was observed. When incubated at 25 degrees C in 100 mM potassium phosphate buffer containing 1 M KCl, pH 8.0, 3-oxoPrMCA released approximately 6% and 3-oxoPrMCA S-oxide released approximately 16-18% of the theoretical maximum yield of acrolein after 30 min, as indicated by an increase in absorbance at 210 nm and confirmed by trapping this aldehyde as a semicarbazone. There was less than a 2% yield of acrolein from 3-hydroxyPrMCA or 3-oxoPrGSH under similar conditions. At pH 7.4 the release of acrolein from 3-oxoPrMCA and 3-oxoPrMCA S-oxide was decreased by 50%. An assay where aldehydes are reacted with m-aminophenol in acid media produced fluorescence consistent with 72%, 46%, 23%, and 1% yields of acrolein from 3-oxoPrMCA S-oxide, 3-oxoPrMCA, 3-oxoPrGSH, and 3-hydroxyPrMCA, respectively.(ABSTRACT TRUNCATED AT 400 WORDS)
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Novichenko N, Konno S, Nakajima Y, Hsieh TC, Xu W, Turo K, Ahmed T, Chiao JW. Growth attenuation in a human prostate cell line mediated by a phorbol ester. PROCEEDINGS OF THE SOCIETY FOR EXPERIMENTAL BIOLOGY AND MEDICINE. SOCIETY FOR EXPERIMENTAL BIOLOGY AND MEDICINE (NEW YORK, N.Y.) 1995; 209:152-6. [PMID: 7770465 DOI: 10.3181/00379727-209-43889] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Human prostatic cancer cells JCA-1 were induced with a phorbol ester 12-o-tetradecanoylphorbol-13-acetate (TPA), and cell growth differentiation were analyzed. Within hours of exposure to TPA, cell proliferation decreased and reached approximately 80% reduction after 3 days, as determined by [3H]thymidine incorporation and cell counting. Cell cycle analysis revealed a blocking of cells entering into the replicating S and G2M phases from the G1 phase. The TPA induced cells had a reduced growth rate but remained viable. The growth-modulating activity of TPA was similarly observed with LNCaP cells. Agarose gel electrophoresis of the chromosomal DNA from induced cells exhibited a non-fragmented pattern excluding the possibility of cell apoptosis. In parallel to the growth reduction, the TPA induced cells became larger in size showing dendrite like cytoplasmic extensions. Furthermore, JCA-1 cells treated with TPA acquired the expression of cytokeratin 18 and increased the expression of actin and vimentin by 300%. These results indicate an induced growth reduction accompanied by cellular differentiation of the prostatic cancer cells.
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249
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Ahmed T. The population of persons with disabilities in Pakistan. ASIA-PACIFIC POPULATION JOURNAL 1995; 10:39-62. [PMID: 12319484] [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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250
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Ahmed T, Lake D, Feldman E, Seiter K, Ali M, Beer M. Marrow transplantation for Hodgkin's disease: points to ponder. Leuk Lymphoma 1995; 15 Suppl 1:25-6. [PMID: 7767255 DOI: 10.3109/10428199509052701] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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