Clinical Implication of Toll-Like Receptors (TLR2 and TLR4) Polymorphisms in Adult Patients with Acute B-cell Lymphoblastic Leukemia.

BACKGROUNDS: Neutropenia after intensive chemotherapy of acute lymphoblastic leukemia (ALL) could lead to infectious complications that affect outcome of acute leukemia patients. Many single-nucleotide polymorphisms (SNPs) of Toll-like receptors (TLRs) can affect the genetic susceptibility to infections. We investigated the impact of different SNPs on the incidence of developing sepsis and pneumonia in patients with newly diagnosed B-ALL following induction chemotherapy. SUBJECTS AND METHODS: We analyzed three SNPs in the TLR2 (Arg753Gln) and TLR4 (Asp299Gly& Thr399Ile) genes using polymerase chain reaction - restriction fragment length polymorphism (PCR-RFLP) in a case control study of 40 precursor B-ALL patients and 50 control subjects. The risk of developing sepsis and pneumonia were assessed by multiple logistic regression analyses. RESULTS: The presence of the TLR-2 AG polymorphism was significantly associated with pneumonia in B-ALL patients. Furthermore, TLR4 Thr399Ile AG was a risk factor for sepsis in B-ALL patients. Moreover; Significant association between TLR-2 AA, TLR-4 CC and TL-4 AA genotypes and longer OS were detected in studied B-ALL patients. CONCLUSION: We concluded that TLR-4 (AG and CT) genotypes are associated with high susceptibility to sepsis and pneumonia respectively; while, TLR-2, TLR-4 AA and TLR-4 CC genotypes  could predict good B-ALL patients outcome.

Leukemic Stem Cell (CD34+/CD38-/TIM3+) Frequency in Patients with Acute Myeloid Leukemia: Clinical Implications.

This study aimed to address the prognostic relevance of CD34+/CD38-/TIM3+ leukemic stem cell (LSC) frequency in patients with acute myeloid leukemia (AML) and its impact on patient outcome. We analyzed the expression of LSC markers (CD34+/CD38-/TIM3+) using flow cytometry in bone marrow samples of 53 AML cases before and after induction chemotherapy. The LSC frequency at diagnosis was significantly higher compared with that postinduction (P < .001). Patients were categorized into high LSC expressers (≥ median) and low expressers (< median). Patients with AML with high number of LSCs at diagnosis had significantly lower induction of remission response (P = .0104), shorter disease-free survival, and shorter overall survival (P < .001 for both) compared with those with lower LSC count. Cox regression analysis revealed that LSC frequency at diagnosis is an independent prognostic factor in AML. Assessment of LSCs (CD34+/CD38-/TIM3+) at diagnosis is recommended for refining of AML risk stratification.

Implications of Glutathione Peroxidase 3 Expression in a Cohort of Egyptian Patients with Acute Myeloid Leukemia.

BACKGROUND: The impact of low expression of Glutathione peroxidase 3 (GPX3) on the clinical course of acute myeloid leukemia (AML) is poorly investigated. AIMS: To explore the status of GPX3 expression and analyze its clinical characteristics and prognosis in a cohort of Egyptian patients with AML. METHODS: GPX3 mRNA level was assessed by RT-q PCR in 40 newly diagnosed AML patients and 10 healthy controls. RESULTS: The gene expression level was significantly lower in AML patients than the control group (P < 0.001). A cut off value (0.1223) for the discrimination between AML and controls was obtained by ROC curve. According to this cutoff value; the patients were reassigned into 2 groups; 28 patients with lower GPX3 expression and 12 patients with high GPX3 expression. GPX3low expression was significantly associated with higher incidence of induction death (P= 0.037) and lower CR rate (P=0.048). Moreover, GPX3low expression was significantly associated with shorter cumulative 1-year overall survival (OS) (P = 0.001) and disease-free survival (DFS) (P=0.028). CONCLUSION: GPX3low expression status is considered a poor prognostic factor in AML predicting shorter OS and DFS. The study highlights the importance of targeting glutathione metabolism as a central component of the anti-leukemia therapy.

Clinical Implication of Toll-Like Receptors (TLR2 and TLR4) in Acute Myeloid Leukemia Patients.

BACKGROUNDS: Toll-like receptors 2; 4 (TLR2;4) are an essential component of the innate immunity and play an important role in immune-surveillance and immune response to various microorganisms. This study aimed to investigate the association between TLR2 and TLR4 polymorphism and the risk of acquiring severe infections, and impact on AML patient's outcome. SUBJECTS AND METHODS: Using polymerase chain reaction - restriction fragment length polymorphism (PCR-RFLP); we analyzed three SNPs in the TLR2 (Arg753Gln) and TLR4 (Asp299Gly and Thr399Ile) in 120 AML patients and 100 healthy control subjects. RESULTS: No significant differences in genotype or alleles frequency between healthy controls and AML patients regarding TLR2 Arg753Gln, TLR4 Asp299Gly and TLR4 Thr399Ile polymorphisms (P>0.05 for all). Neutropenic fever was detected in 110 out of 120 (91.7%) of the studied AML patients. The sepsis and pneumonia were identified in 20 out of 120 patients (16.7%). The incidence of sepsis was associated with TLR2 Arg753Gln: AG genotypes, A allele and TLR4 Asp299Gly: CT genotype and C allele as compared to other genotypes and alleles. Moreover; TLR2 (Arg753Gln) GG polymorphisms significantly associated with shortest overall survival (OS) and shortest disease-free survival (DFS); while TLR4 polymorphisms affect the DSF only but not OS. In AML patients TLR2 Arg753Gln gene polymorphism is associated with high susceptibility to sepsis and TLR4 (Asp299Gly and Thr399Ile) gene polymorphism is associated with high susceptibility for both pneumonia; and sepsis. CONCLUSION: TLR2 Arg753Gln (AG; GG genotype) polymorphisms are associated with shortest OS and DFS. Moreover; significant association between TLR2 polymorphisms, TLR4 Arg753Gln polymorphisms and risk of severe infections in AML patients was documented.
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Prognostic Significance of Absolute Lymphocyte Count, Absolute Monocyte Count, and Absolute Lymphocyte Count to Absolute Monocyte Count Ratio in Follicular Non-Hodgkin Lymphoma.

INTRODUCTION: Recently, the lymphocyte to monocyte ratio (LMR) has been proposed as an easily determinable prognostic factor in patients with cancer, including lymphomas. The objective of this study was the evaluation of the impact of baseline absolute lymphocyte count (ALC), absolute monocyte count (AMC), and the LMR on the treatment response and prognosis in follicular lymphoma (FL). PATIENTS AND METHODS: The data of 100 patients with a FL variant, admitted and treated between January 2009 and June 2018, were analyzed. RESULTS: The area under the receiver operator characteristic curve and cutoff values of ALC, AMC, and LMR for discrimination between survival times using receiver operating characteristic curves showed 0.57 × 109/L as the most discriminative ALC cutoff value, 1.235 ×109/L as the most discriminative AMC cutoff value, and 1.63 as the most discriminative LMR cutoff value. Progressive disease and stable disease after first-line therapy and mortality rate were significantly associated with lower ALC, higher AMC, and higher LMR. Shorter overall survival (OS) was significantly associated with patients with lower ALC when compared with those having higher ALC. Shorter OS and progression-free survival (PFS) were significantly associated with higher AMC when compared with those having lower AMC. Shorter OS and PFS were significantly associated with lower LMR when compared with those having higher LMR. High-risk Follicular Lymphoma International Prognostic Index as well as low LMR were considered as risk factors for prediction of OS in all the studied patients with FL in univariate analysis and multivariate analysis. CONCLUSION: ALC, AMC, and LMR at diagnosis are simple indices, which reflect the host systemic immunity and can predict the clinical outcomes in FL.

Clinical Significance of CD200 and CD56 Expression in Patients with Acute Myeloid Leukemia.

BACKGROUND: Acute myeloid leukemia (AML) escape from immunosurveillance by immunosuppression. CD200 and CD56 expression represented an independent prognostic factor in many hematological malignancies but its importance in AML patients remains to be identified. METHODS: CD200 and CD56 expression were assessed in the bone marrow blasts for Fifty-two (52) newly diagnosed AML by flowcytometry before start of therapy. RESULTS: CD200+ expression was reported in 28.8% of patients while 17.3% of patients showed CD56+ expression. M4 FAB revealed high frequency of both CD200+ and CD56+ expression. The overall survival of CD200+ patients was 19.2% compared to 35.3% in CD200- (P= 0.049). On the other hand, CD56+ patients had the lowest complete remission rate (22.2% vs. 53.4%). In addition, CD56+ population had significant bad influence on overall survival than those of CD56- population (11.1 % vs. 35.5 %, P= 0.047). CONCLUSIONS: CD200 and CD56 positive expression by myeloblasts at diagnosis denote poor prognostic indicator and correlated with poor cytogenetic findings. CD200 could be used as therapeutic target in AML.
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The prevalence and prognostic significance of autoimmune cytopenias in a cohort of Egyptian patients with chronic lymphocytic leukemia.

OBJECTIVE/BACKGROUND: The impact of autoimmune cytopenias (AICs) on the chronic lymphocytic leukemia (CLL) clinical course and its prognostic significance remain a matter of controversial debate. This could be due to exclusion of patients with cytopenia from most clinical trials for this particular complication and the lack of standard diagnostic criteria and treatment approaches. We herein evaluate the prevalence and the prognostic significance of AICs among patients with CLL. METHODS: This is an observational retrospective study. Data on 101 patients with CLL were derived from the Oncology Center, Mansoura University, Egypt, database, which contains information on demographic and clinical characteristics at diagnosis and follow-up records. RESULTS: The prevalence of immune cytopenias was 11.9% among patients studied. Autoimmune hemolytic anemia was the most common autoimmune form in patients with cytopenia due to pure immune etiology (C immune group) with a prevalence of 6.9%. Patients with AICs and those in the C immune subgroup presented with more unfavorable parameters. Besides, patients with AICs showed lesser response to treatment and on restaging after initial treatment, significantly more patients without AICs moved to a more favorable stage. However, no parallel significant difference in the overall survival was found between patients without AICs and those with AICs or with immune and combined or infiltrative cytopenia. CONCLUSION: We have shown a prevalence of 11.8% for AIC among our CLL patients. AIC was associated with unsatisfactory normalization of the hematological parameters even with therapy and lower number of patients with CLL downstaging in comparison with patients without AIC. These results suggest that AIC is a fingerprint of a biologically more aggressive disease even if no significant impact on overall survival was found.

Prognostic impact of CD200 and CD56 expression in adult acute lymphoblastic leukemia patients.

BACKGROUND: The aim of the study is to determine the prognostic relevance of CD200/ CD56 expression in adult acute lymphoblastic leukemia patients. METHODS: The expression of CD200 and CD56 by blast cells was assessed by flow cytometry before the start of chemotherapy in 70 B-ALL patients. RESULTS: Positive expression of CD200 was detected in forty-six patients (66%) and CD56 was detected in 7 patients (10%) out of 70 patients, respectively. Only three patients (4.3%) had co-expression for CD200+ and CD56+. Splenomegaly and thrombocytopenia were frequently observed more in CD200+ patients. Increased frequency of CD34+ was associated with CD200+and CD56+ patients. The CD200+ and CD56+ subgroups of B-ALL patients had inferior OS and disease free survival compared to CD 200- and CD 56- patients. CONCLUSIONS: CD200+ and/or CD56+ positive expression in B-ALL patients at diagnosis is a poor prognostic biomarker. Identification of CD200+ and CD56+ expression at diagnosis is recommended for a better stratification of adult B-ALL patients.

Hypercalcemia With Disseminated Osteolytic Lesions: A Rare Presentation of Adulthood Acute Lymphoblastic Leukemia.

Osteolytic bone lesions and hypercalcemia without peripheral blasts B-cell acute lymphoblastic leukemia (B-ALL) are reported in children but rarely seen in adults. Herein, we described two patients with B-ALL presenting with hypercalcemia and symptomatic osteolytic bone lesions. They were treated by standard induction chemotherapy after correction of hypercalcemia with supportive measures. With this two case reports we would like to emphasize the importance of clinical awareness of hypercalcemia and osteolytic bone lesions as rare presentations of ALL. The prognostic implication of bone lesions and hypercalcemia in ALL is unclear and needs to be verified in large prospective studies. However, immediate recognition and treatment of hypercalcemia and the underlying B-ALL are vital since a delay of diagnosis poses a possible life-threatening risk.

Pregnancy associated acute leukemia: Single center experience.

INTRODUCTION: Data regarding clinical characteristics, therapy, maternal and fetal outcomes of pregnancy-associated acute leukemia are limited. PATIENTS AND METHODS: We herein, present the data of 27 pregnancy associated acute leukemia [18 acute myeloid leukemia (AML) and 9 acute lymphatic leukemia (ALL)]. Their data were compared to an age matched group of 75 non-pregnant acute leukemia patients admitted and treated during the same period [53 AML and 22 ALL]. RESULTS: Complete remission rates, induction failure and induction deaths showed insignificant differences in pregnant versus non pregnant patients in both types of acute leukemia. Similarly, OS and DFS showed no significant difference between pregnant versus non pregnant patients in both types of acute leukemia. Cox regression analysis was conducted for prediction of OS and DFS in all the studied patients applying age, WBCs, BM blasts, LDH, cytogenetic abnormalities and pregnancy as covariates, Pregnancy was not considered as a risk factor for OS or PFS in univariate or multivariate analysis. CONCLUSION: Our report to the best of our knowledge is the first to present direct evidence that pregnancy has no significant impact on outcome of acute leukemia compared to non-pregnant patients. These results are limited by the small number of cases and should be confirmed in a prospectively larger cohort of patients.

Increased expression of costimulatory molecules CD86 and sCTLA-4 in patients with acute lymphoblastic leukemia.

We herein evaluate the role of the B7-family molecule CD86 and the Cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) as a possible immunopathogenic factors in patients with ALL. The results of 60 patients with de novo ALL were compared to 40 controls. A significant statistical difference between CD86 expression and sCTLA-4 levels in patients versus their controls has been detected. During follow up period of 28 months, patients suffered from relapse (16 patients) had significantly higher CD86 expression and sCTL-4 levels compared to those remained in complete remission (44 patients) (p = 0.005 and 0.03 respectively). Patients who died from the disease (9 patients) showed significantly higher CD 86 expression and sCTLA-4 levels than surviving patients (51 patients) (p = 0.004 and 0.01 respectively). In conclusion, the higher levels of sCTLA-4 and CD86 in B-ALL patients might be candidate parameters for poor prognosis and may serve to refine treatment stratification with intensification of therapy in those patients prone to relapse.

Mesenchymal stem cell-based therapy for the treatment of type 1 diabetes mellitus.

The pathophysiology of Type 1 diabetes (T1D) appears largely related to an innate defect in the immune system culminating in a loss of self tolerance and destruction of the insulin producing ß-cells. Currently, there is no definitive cure for diabetes. Insulin injection does not mimic the precise regulation of ß-cells on glucose homeostasis, leading long term to the development of complications. Other therapeutic approaches therefore, are necessary and cell therapy is thought to be a possible approach. In this sense, mesenchymal stem cells (MSCs) can offer a promising possibility that deserves to be explored. MSCs are multipotent non-hematopoietic progenitor cells. Their therapeutic potentials have recently been brought into the spotlights of many fields of research. Although the regenerative capabilities of MSCs have been a driving force to initiate studies testing their therapeutic effectiveness, their immunomodulatory properties have been equally exciting. MSCs possess specific immunomodulatory properties that would appear capable of disabling immune dysregulation that leads to ß-cell destruction in T1D. Furthermore, MSCs can be sequentially cultured in specially defined conditions and their differentiation extends toward the ß-cell phenotype and the formation of insulin producing cells (IPCs). To date, the role of MSCs in T1D remains completely unexplored. We herein summarize multiple strategies that have been proposed and tested for its potential therapeutic benefit for T1D.

The potential utility of bone marrow or umbilical cord blood transplantation for the treatment of type I diabetes mellitus.

The pathology of type 1 diabetes mellitus (T1D) involves the autoimmune destruction or malfunction of pancreatic ß cells, leading to a lack of insulin. The absence of insulin is life-threatening, necessitating daily hormone injections from an exogenous source. Insulin injections do not adequately mimic the precise regulation of ß cells on glucose homeostasis, however, eventually leading to complications in diabetic patients. There currently is no definitive cure for T1D. Pancreas transplantation, although quite successful, is an invasive intervention that is restricted to patients with advanced complications, requires constant immunosuppression, and is severely limited by donor availability. Recent progress in human islet cell isolation and immunosuppressive protocols has restored euglycemia in patients who received islet cells from 2 or 3 pancreas donors. However, because of the scarcity of cadaver pancreata and the low yield of islet cells obtained by the procedure, not all patients have access to this surgical intervention. Thus, other therapeutic approaches are needed to arrest immune aggression, preserve ß cell mass, and provide efficient replacement. In this sense, bone marrow and umbilical cord blood transplantation are promising possibilities that merit exploration. In this review, we summarize multiple strategies that have been proposed and tested for potential therapeutic benefit in patients with T1D.

A randomized controlled trial of transcatheter arterial chemoembolization with lipiodol, doxorubicin and cisplatin versus intravenous doxorubicin for patients with unresectable hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is a major and often therapeutically frustrating oncological problem. A total of 100 patients with unresectable HCC were recruited and randomized to be treated with either transcatheter arterial chemoembolization (TACE) or systemic chemotherapy. Fifty patients were treated with TACE using lipiodol, doxorubicin and cisplatin, while 50 patients were treated with systemic doxorubicin alone. Patients treated with TACE achieved a significantly higher response rate, with partial response achieved in 16 patients (32%) versus five patients (10%) in the chemotherapy arm (P = 0.007). A significantly more favourable tumour response to chemoembolization was found in patients with single lesions (P = 0.02), Child class A (P = 0.007), Okuda stage 1 (P = 0.005) and alpha-feto protein less than 400 ng/mL (P < 0.001). The probability of tumour progression was significantly lower in cases treated with TACE where the median progression free survival was 32 weeks (range, 16-70 weeks) versus 26 weeks (range, 14-54 weeks) for patients treated with systemic chemotherapy (P = 0.03). However, the median overall survival did not differ significantly in cases treated with TACE (38 weeks) compared with those treated with chemotherapy (32 weeks) (P = 0.08), except for patients with serum albumin >3.3 g/dL (60 vs. 36 weeks; P = 0.003). Multivariate Cox regression analysis showed that a rise of serum albumin by 1 g/dL is associated with a decrease in the risk of death by 33% (95% confidence interval: 0.12-0.94, P = 0.038). Mortality in the chemoembolization arm was due to tumour progression in 18 patients (53%), liver failure in 11 patients (32%) and gastro intestinal tract (GIT) bleeding in 5 patients (15%). Mortality in the chemotherapy arm was due to tumour progression in 23 patients (64%), liver failure in 9 patients (25%) and GIT bleeding in 4 patients (11%). Treatment-related mortality was 4% in the TACE arm versus 0% in the chemotherapy arm. In conclusion, the overall survival benefits of TACE and systemic doxorubicin are similar for patients with unresectable HCC amenable to either treatment. It is crucial to optimize the benefit-risk ratio of TACE. In this setting, serum albumin level is a candidate marker for selection of cases who may benefit from this procedure.

High-dose chemotherapy plus non-cryopreserved autologous peripheral blood stem cell transplantation rescue for patients with refractory or relapsed Hodgkin disease.

A simplified schedule of high-dose chemotherapy consisting of cyclophosphamide (60 mg.kg(-1).d(-1) for 2 days), etoposide (15 mg.kg(-1).d(-1) for 2 days), and carboplatin (400 mg/m(2) per day for 2 days) plus autologous non-cryopreserved peripheral blood stem cells (PBSCs) was used for treatment of patients with relapsed (n = 25) and refractory (n = 3) Hodgkin disease. The use of such PBSCs mobilized by granulocyte colony-stimulating factor after high-dose myeloablative therapy resulted in a rapid, complete, and sustained hematopoietic recovery. The median time to achieve an absolute neutrophil count >0.5 x 10(9)/L was 13 days (range, 7-18 days). The median time to a self-sustained platelet count >20 x 10(9)/L was 15 days (range, 7-20 days). Twelve of the 28 patients (43%) were alive and without disease at a median follow-up of 16 months (range, 9-86 months) for all surviving patients. The estimated 2-year overall survival and disease-free survival for all patients were 45% and 42%, respectively. Thirteen patients died of relapse or progressive disease, 2 died of infection, and 1 was still surviving in relapse by the time of the analysis. The median time to relapse was 10 months (range, 3-28 months) from PBSC infusion. High-dose chemotherapy with short-duration chemotherapy and non-cryopreserved bone marrow is an effective and safe treatment modality for patients with relapsed or resistant Hodgkin lymphoma.

Differential sensitivity of T lymphocytes and hematopoietic precursor cells to photochemotherapy with 8-methoxypsoralen and ultraviolet A light.

The combination of 8-methoxypsoralen (8-MOP) and long wave ultraviolet radiation (UV-A) has immunomodulatory effects and might abolish both graft-vs-host and host-vs-graft reactions after allogeneic hematopoietic stem cell transplantation. In the present study, we have confirmed the sensitivity of T lymphocytes to 8-MOP treatment plus UV-A exposure as evidenced by the abrogation of the alloreactivity in mixed lymphocyte cultures as well as the inhibition of the response to phytohemagglutinin A. However, the clonogenic capacity of the bone marrow hematopoietic progenitors was inhibited with UV-A doses lower than the doses needed to inhibit T-lymphocytes alloreactivity. Moreover, long-term bone marrow cultures showed that 8-MOP plus UV-A treatment had detrimental effects on the more immature bone marrow stem cells. These data were confirmed when murine bone marrow graft was treated with 8-MOP, exposed to UV-A, then transplanted into semiallogeneic recipient mice. The treated cells could not maintain their clonogenic capacity in vivo resulting in death of all animals. Taken together, these data show that ex vivo 8-MOP plus UV-A treatment of the marrow graft cannot be used to prevent post-bone marrow transplantation alloreactivity.

Chlorambucil plus theophylline vs chlorambucil alone as a front line therapy for B-cell chronic lymphatic leukemia.

B-cell chronic lymphatic leukemia (B-CLL) has emerged as a prototype of malignancies characterized by a defective apoptosis that leads to a progressive accumulation of monoclonal B cells in the bone marrow, lymphoid tissues and peripheral blood. Chlorambucil, an aromatic derivative of nitrogen mustards, is the most common treatment for chronic lymphatic leukemia (CLL). The response rate with its use is 40 to 60%, with 3 to 10% only of patients achieving a complete response (CR). To improve response rates, chlorambucil has been combined with steroids or other agents. Theophylline, a methylxanthine commonly used as a treatment for asthma, has been shown to induce apoptosis in CLL cells both in vitro and in vivo. Chlorambucil induces apoptosis in CLL cells as well and synergy has been shown between the two drugs without affecting the normal B lymphocytes. The aim of this work was to evaluate the potential utility of this combination as a therapeutic modality for B-CLL. A total of 210 B-CLL patients were recruited and randomized to receive either chlorambucil in an oral dose of 0.1 mg/kg/day indefinitely (109 patients) or chlorambucil 0.1 mg/kg/day plus theophylline 200 mg bid, orally (101 patients). The main endpoints were overall survival from the time of randomization, disease status after 9 months and time to disease progression. After 9 months of treatment, clinical and hematological remission was achieved in 14 patients (12.8%) in the chlorambucil group, compared to 26 (25.7%) in the chlorambucil plus theophylline group (P value 0.01). Partial remission was observed for 38 patients (34.9%) in the chlorambucil group and 36 patients (35.7%) in the chlorambucil plus theophylline group. In patients treated with chlorambucil alone, the median progression-free survival (PFS) was 30 months and in patients treated with chlorambucil plus theophylline it was 44 months. Probabilities of PFS at 24 months for the chlorambucil-treated patients were 59% and 85% for the chlorambucil plus theophylline-treated patients. The difference was statistically significant (P = 0.006). The 3-year and 5-year overall survival rates were, respectively 75% and 38% in the chlorambucil group as opposed to 76% and 46% in the chlorambucil plus theophylline group. The median survival time was 55 months in the chlorambucil group and 56 months in the chlorambucil plus theophylline group. Forty-nine patients died in the chlorambucil group compared to 44 patients in the chlorambucil plus theophylline group (P = 0.371). The trial has demonstrated that adding theophylline to the standard treatment of B-CLL significantly increases effectiveness of treatment in terms of tumor response and time to disease progression. It could not improve the overall survival. Treatment with theophylline does not compromise quality of life or add significant toxicity. As newer drugs have recently become available for treating patients with CLL like fludarabine, further trials are needed to evaluate the effect of combining theophylline with these drugs.