Rare congenital Dyserythropoietic anemia of childhood: A case report.

Congenital dyserythropoietic anemias (CDA) is a heterogeneous class of anemia of varying degrees of ineffective erythropoiesis and secondary hemochromatosis. We reported a case of CDA and showed our approach to reaching a diagnosis, highlighting the importance of the typical morphological appearance of bone marrow erythroblasts to reach the diagnosis.

Key determinants of deposits volume using CAMEL rating system: The case of Saudi banks.

CAMEL is considered one of the well-known banking rating systems used to build a proper bank ranking. In our paper, we investigate the CAMEL rating for Saudi banks, which is considered the second largest banking sector in GCC. The Saudi banking sector consists of 11 banks and is the leading sector in the Saudi stock index (TASI). In this research, we aim to determine the ranking of Saudi banks according to CAMEL composite and CAMEL overall ratings and explore the effects of these ratings on banks' total deposits for the period from 2014 to 2018. The methodology involves four phases. In the first phase, we calculate the key financial ratios of CAMEL's composites for each bank. In the second phase, we rank the banks from 1 to 11 to each one of CAMEL's composites for each bank per year. In the third phase, we rank Saudi banks according to CAMEL composite and CAMEL overall. Finally, in the fourth phase, we run a regression model using CAMEL financial ratios rank as independent variable and banks' total deposits as a dependent variable. Using the stepwise regression method, the results indicated that the best regression model has an adjusted R2 of 73.4% and a standard error of around 0.58. The results further indicated that capital measured by CAR, management as an efficiency ratio, earning with ROE proxy, and liquidity as loans to deposits have positive effects on banks' total deposits. Meanwhile, earnings as net interest income to net revenue and liquidity calculated by CASA have a negative effect on banks' total deposits. Finally, asset quality ratios and the rest of the ratios have no significant effect on banks' total deposits.

Hepatitis C virus therapy is associated with lower health care costs not only in noncirrhotic patients but also in patients with end-stage liver disease.

BACKGROUND: The effect of anti-viral treatment on downstream costs for hepatitis C virus (HCV)-infected patients is unknown. AIM: To evaluate follow-up costs in patients with chronic HCV, stratified by liver disease severity. METHODS: Using a US private insurance database, mean all-cause per-patient-per-month (PPPM) US (2010) medical costs were calculated for HCV-infected persons who did and did not receive anti-HCV treatment between January 2002 and August 2010. Analysis was stratified by liver disease severity [noncirrhotic disease (NCD), compensated cirrhosis (CC) or end-stage liver disease (ESLD)] defined by ICD-9 and CPT codes. RESULTS: A total of 33 309 patients were included (78% NCD, 7% CC and 15% ESLD); 4111 individuals (12%) received anti-HCV treatment during the 2-year baseline period. Mean PPPM follow-up health care costs were significantly lower among treated patients with NCD ($900 vs. $1378 in untreated patients, P < 0.001) and ESLD ($3634 vs. $5071, P < 0.001) groups but not in the CC group ($1404 vs. $1795, P < 0.071; t-test). In a multivariable model adjusted for demographic characteristics, comorbidities, index date and geographical region, incremental cost ratios for total health care costs differed significantly (P < 0.001) between treated and untreated patients in the NCD and ESLD groups but not in the CC group. From this model, mean PPPM total health care costs between treated and untreated patients were $885 and $1370 in the NCD, $1369 and $1802 in the CC, and $3547 and $5137 in the ESLD groups, respectively. CONCLUSIONS: Anti-HCV therapy was associated with lower follow-up US health care costs, and these savings were independent of baseline patient comorbidities and stage of disease.

Characterization of nonrapid virologic response patients infected with HCV genotype 1 who may relapse after standard therapy with peginterferon plus ribavirin.

Approximately 50% of patients with hepatitis C virus (HCV) genotype 1 treated with peginterferon alfa-2a/ribavirin discontinue treatment early or experience a suboptimal response despite 48 weeks of therapy. The objective of this analysis was to develop a model to identify nonrapid virologic response (non-RVR) patients who may be candidates for intensified therapy that would increase treatment response. The retrospective analysis included non-RVR patients from four trials of 48-week peginterferon alfa-2a/ribavirin treatment. Patients were grouped into those who cleared virus between weeks 5 and 12 (complete early virologic responders, cEVR) or between weeks 13 and 24 (slow responders). A model was developed to predict relapse at the end of follow-up (week 72). An optimal model was evaluated and compared with current practice by using receiver operating characteristic curves, sensitivity and specificity. In total, 539 non-RVR patients were eligible for analysis of which 72% experienced cEVR and 28% were slow responders. Variables associated with relapse included age, ethnicity, baseline HCV RNA and interval of time to HCV RNA undetectable. The optimal model was most accurate at predicting patients at risk for relapse. The practice of considering treatment intensification (e.g. extending treatment duration) in all slow responders was less accurate but likely most practical. A week 4 HCV <2-log reduction was the earliest but least accurate marker. We developed a model that could identify non-RVR patients at high risk for relapse after 48 weeks of peginterferon alfa-2a plus ribavirin and who may benefit from intensified therapy to reduce this risk of relapse.

Factors associated with rapid and early virologic response to peginterferon alfa-2a/ribavirin treatment in HCV genotype 1 patients representative of the general chronic hepatitis C population.

Rapid virologic response (RVR) and complete early virologic response (cEVR) are associated with sustained virologic response to hepatitis C virus (HCV) therapy. We retrospectively examined baseline and on-treatment factors associated with RVR (HCV RNA undetectable at week 4) and cEVR (HCV RNA undetectable at week 12, regardless of week 4 response). The analysis comprised 1550 HCV genotype-1 patients from five clinical trials, including three enriched with difficult-to-treat populations, randomized to peginterferon alfa-2a 180 microg/week plus ribavirin 1000-1200 mg/day. Overall, 15.6% achieved RVR and 54.0% achieved cEVR. Baseline factors predictive of RVR were serum HCV RNA 3 x ULN (OR: 2.01; P < 0.0001), non-cirrhotic status (OR: 1.92; P = 0.0087), age 13 mg/kg/day was predictive of RVR (OR: 1.69; P = 0.005) and cEVR (OR: 1.24; P = 0.09), whereas peginterferon alfa-2a dose reduction was not. Greater decreases in haematologic parameters were observed in patients who achieved cEVR compared with patients who did not. In conclusion, several baseline and on-treatment factors were associated with RVR and cEVR to peginterferon alfa-2a plus ribavirin in difficult-to-treat HCV genotype-1 patients, providing important prognostic information on the antiviral response in a patient cohort that is reflective of the general chronic hepatitis C population.

Peginterferon alfa-2a/ribavirin in hepatitis C virus patients nontolerant or nonresponsive to peginterferon alfa-2b/ribavirin.

BACKGROUND: Peginterferon alfa-2a/ribavirin treatment resulted in fewer incidences of depression and flu-like symptoms than that of standard interferon/ribavirin, whereas peginterferon alfa-2b/ribavirin and standard interferon/ribavirin treatment resulted in similar incidences of these adverse events (AEs). AIM: To assess the efficacy and safety of peginterferon alfa-2a/ribavirin in genotype 1-infected patients treated for up to 12 weeks with peginterferon alfa-2b/ribavirin but not achieving early virologic response (EVR) (non-EVR) or nontolerant (NT) because of depression, fatigue, flu-like symptoms, or injection-site reactions. METHODS: Nontolerants were treated for an additional 36 weeks and non-EVRs for an additional 60 weeks with peginterferon alfa-2a (180 microg/week)/ribavirin (1000/1200 mg/day). Patients with detectable HCV RNA after 12 weeks were discontinued. RESULTS: Of 25 NTs, 23 (92%) were HCV-RNA negative after 12 weeks on peginterferon alfa-2a/ribavirin and 14 (56%) achieved sustained virologic response. Of 32 non-EVRs to peginterferon alfa-2b/ribavirin, four (13%) achieved EVR with peginterferon alfa-2a/ribavirin and one (3%) achieved sustained virologic response. Four non-EVRs and 0 NTs were withdrawn for AEs; 26 (81%) and 24 (96%), respectively, completed peginterferon alfa-2a/ribavirin treatment or were withdrawn for insufficient response at week 12. In NTs, depression, fatigue, flu-like symptoms, and injection-site reactions declined during treatment. CONCLUSION: Most patients who did not tolerate peginterferon alfa-2b/ribavirin because of AEs, and who completed the full 36-week course of peginterferon alfa-2a/ribavirin treatment, achieved sustained virologic response.

Early virologic response after peginterferon alpha-2a plus ribavirin or peginterferon alpha-2b plus ribavirin treatment in patients with chronic hepatitis C.

Patients infected with hepatitis C virus (HCV) genotype 1 and with serum HCV RNA concentrations over 800 000 IU/mL have relatively low rates of virologic response to pegylated interferons. The 2 forms of pegylated interferon have different pharmacokinetic profiles, and pilot studies comparing them have yielded varying results. We compared the virologic response to 12 weeks of treatment with peginterferon alpha-2a plus ribavirin vs peginterferon alpha-2b plus ribavirin in 380 patients who were infected with HCV genotype 1 and had high viral loads. We observed no between-group differences in viral load reduction over time and no differences in the percentage of patients treated with peginterferon alpha-2a or peginterferon alpha-2b plus ribavirin who achieved early virologic response (EVR), defined as >/=2-log reduction in HCV RNA concentration or undetectable HCV RNA at 12 weeks (66%vs 63%). Serum levels of interferon were more frequently below the level of quantitation in patients treated with peginterferon alpha-2b plus ribavirin (58-68%) than in those treated with peginterferon alpha-2a plus ribavirin (1-2%). Patients treated with peginterferon alpha-2b plus ribavirin had higher rates of discontinuation for safety reasons (6%vs 1%). In conclusion, a substantial percentage of patients infected with HCV genotype 1 and high viral load can achieve EVR when treated with peginterferon and ribavirin. The 2 pegylated interferons showed comparable anti-HCV activity during the first 12 weeks of treatment when combined with the same doses of ribavirin (1000-1200 mg/day), but discontinuations for safety reasons were higher in the patients treated with peginterferon alpha-2b plus ribavirin.

Improved CNS tolerability following conversion from immediate- to extended-release carbamazepine.

OBJECTIVES: Tolerability of 'narrow therapeutic ratio' (NTR) antiepileptic drugs may improve with uniform drug delivery. We determined whether conversion from immediate-release carbamazepine (IR-CBZ) to extended-release carbamazepine (ER-CBZ) decreased the incidence of CNS side-effects associated with drug concentration oscillations. METHODS: We compared CNS side effects and seizure frequency for patients with partial-onset seizures (n = 61) treated with IR-CBZ for > or =1 year with conversion to ER-CBZ for > or =1 year. We compared tolerability findings with absorption variability of the formulations. RESULTS: Incidence of CNS side-effects decreased from 49% during IR-CBZ treatment to 20% following conversion to ER-CBZ. Patients also had improved tolerability of high doses (> or =1200 mg/day) during ER-CBZ treatment. Pharmacokinetic analysis showed absorption and drug concentration were much more variable for the immediate-release formulation. CONCLUSIONS: This study suggests that ER-CBZ formulations, with smoother drug delivery and less variable absorption, provide improved CNS tolerability compared with immediate-release formulations.

Induction of Epstein-Barr virus kinases to sensitize tumor cells to nucleoside analogues.

The presence of Epstein-Barr virus (EBV) in the tumor cells of some EBV-associated malignancies may facilitate selective killing of these tumor cells. We show that treatment of an EBV(+) Burkitt's lymphoma cell line with 5-azacytidine led to a dose-dependent induction of EBV lytic antigen expression, including expression of the viral thymidine kinase (TK) and phosphotransferase (PT). Azacytidine treatment for 24 h modestly sensitized the cell line to all nucleosides tested. To better characterize EBV TK with regard to various nucleoside analogues, we expressed EBV TK in stable cell clones. Two EBV TK-expressing clones were moderately sensitive to high doses of acyclovir and penciclovir (PCV) (62.5 to 500 microM) and to lower doses of ganciclovir (GCV) and bromovinyldeoxyuridine (BVdU) (10 to 100 microM) compared to a control clone and were shown to phosphorylate GCV. Similar experiments in a transient overexpression system showed more killing of cells transfected with the EBV TK expression vector than of cells transfected with the control mutant vector (50 microM GCV for 4 days). A putative PT was also studied in the transient transfection system and appeared similar to the TK in phosphorylating GCV and conferring sensitivity to GCV, but not in BVdU- or PCV-mediated cell killing. Induction of EBV kinases in combination with agents such as GCV merits further evaluation as an alternative strategy to gene therapy for selective killing of EBV-infected cells.

Chemotherapy for human immunodeficiency virus-associated non-Hodgkin's lymphoma in combination with highly active antiretroviral therapy.

PURPOSE: This study investigated the efficacy, toxicity, and pharmacokinetic interactions resulting from simultaneous combination chemotherapy and highly active antiretroviral therapy (HAART) for patients with human immunodeficiency virus (HIV)-associated non-Hodgkin's lymphoma (NHL). In addition, the effects on viral load, CD4 counts, and opportunistic infections were examined with the use of combination chemotherapy combined with HAART. PATIENTS AND METHODS: Sixty-five patients with previously untreated and measurable disease at any stage of HIV-associated NHL of intermediate or high grade were entered onto this study at 17 different centers. The first 40 patients entered onto the study received reduced doses of cyclophosphamide and doxorubicin, combined with vincristine and prednisone (modified CHOP [mCHOP]), whereas the subsequent 25 patients entered onto the study received full doses of CHOP combined with granulocyte colony-stimulating factor (G-CSF). All patients also received stavudine, lamivudine, and indinavir. RESULTS: The complete response rates were 30% and 48% among patients who received mCHOP and full-dose CHOP combined with HAART, respectively. Grade 3 or 4 neutropenia occurred in 25% of patients receiving mCHOP and 12% of those receiving full-dose CHOP combined with G-CSF (25% v 12%). There were similar numbers of patients with grade 3 or 4 hyperbilirubinemia (12% and 17%), constipation and abdominal pain (18% and 17%), and transaminase elevation (48% and 52%) on the modified and full-dose arms of the study, respectively. Doxorubicin clearance and indinavir concentration curves were similar among patients on this study and historical controls, whereas cyclophosphamide clearance was 1.5-fold reduced as compared with control values. Human immunodeficiency virus (HIV) load declined from a median baseline value of 29,000 copies/mL to a median minimum value on therapy of 500 copies/mL. CONCLUSION: Either modified-dose or full-dose CHOP chemotherapy for HIV-NHL, delivered with HAART, is effective and tolerable.

Clinical and pathological findings of a newly recognized disease of elephants caused by endotheliotropic herpesviruses.

The unique clinical and pathological findings in nine Asian (Elephas maximus) and two African (Loxodonta africana) elephants from North American Zoos with a highly fatal disease caused by novel endotheliotropic herpesviruses are described. Identification of the viruses by molecular techniques and some epidemiological aspects of the disease were previously reported. Consensus primer polymerase chain reaction (PCR) combined with sequencing yielded molecular evidence that confirmed the presence of two novel but related herpesviruses associated with the disease, one in Asian elephants and the second in African elephants. Disease onset was acute, with lethargy, edema of the head and thoracic limbs, oral ulceration and cyanosis of the tongue followed by death of most animals in 1 to 7 days. Pertinent laboratory findings in two of three clinically evaluated animals included lymphocytopenia and thrombocytopenia. Two affected young Asian elephants recovered after a 3 to 4 wk course of therapy with the anti-herpesvirus drug famciclovir. Necropsy findings in the fatal cases included pericardial effusion and extensive petechial hemorrhages in the heart and throughout the peritoneal cavity, hepatomegaly, cyanosis of the tongue, intestinal hemorrhage, and ulceration. Histologically, there were extensive microhemorrhages and edema throughout the myocardium and mild, subacute myocarditis. Similar hemorrhagic lesions with inflammation were evident in the tongue, liver, and large intestine. Lesions in these target organs were accompanied by amphophilic to basophilic intranuclear viral inclusion bodies in capillary endothelial cells. Transmission electron microscopy of the endothelial inclusion bodies revealed 80 to 92 nm diameter viral capsids consistent with herpesvirus morphology. The short course of the herpesvirus infections, with sudden deaths in all but the two surviving elephants, was ascribed to acute cardiac failure attributed to herpesvirus-induced capillary injury with extensive myocardial hemorrhage and edema.

Febrile neutropenia in cancer patients in a tertiary care medical center in Lebanon: microbial spectrum and outcome.

We prospectively analyzed the episodes of febrile neutropenia at the American University of Beirut Medical Center. One hundred and four episodes were studied in 64 patients over a period of 15 months: 81 (78%) with leukemia, 11 (10.5%) with lymphoma, 3 (2.8%) with multiple myeloma, and 9 (8.6%) with solid tumors. Bacteremia was confirmed in 30 episodes (29%), of which 18 (60%) were caused by gram-negative bacilli and 12 (40%) by gram-positive cocci. The predominant organisms were: E. coli (9), coagulase negative staphylococci (CNS) (6), Pseudomonas aeruginosa (5), and S. aureus (4). In seven episodes (6.7%) urinary tract infections were diagnosed, 6 with E. coli. Sputum cultures were positive in eight episodes (7%), 2 with P. aeruginosa, and 2 with methicillin resistant S. aureus. All patients were started empirically on antibacterial agents. In twenty-one episodes, a single antibiotic was started, ceftazidime being the most commonly used agent. In most cases, however, 2 or 3 antibacterial agents were started empirically. Antifungal therapy with amphotericin B (11) or fluconazole (20) was added because of persistent fever despite broad antibacterial coverage. Thirteen patients died (20%), 6 of them had bacteremia; 2 with gram-negative bacilli, and 4 with gram-positive cocci. Except for one, all patients had been started, at the onset of the fever, on antimicrobial agents to which the isolated microorganisms turned out to be susceptible. Our results show that infections with gram-negative bacteria continue to predominate unlike what has been reported recently from European and North American trials. A trend toward a higher mortality of infections caused by gram-positive cocci was noted.

Human herpesvirus 8-encoded thymidine kinase and phosphotransferase homologues confer sensitivity to ganciclovir.

Human herpesvirus 8 (HHV-8) sensitivity to the nucleoside analog ganciclovir (GCV) suggests the presence of a virally encoded kinase that catalyzes the initial phosphorylation of GCV. Analysis of the HHV-8 genome identified two candidate kinases: proteins encoded by open reading frame (ORF) 21, with homology to the herpesvirus thymidine kinases (TK), and ORF 36, with homology to the herpesvirus phosphotransferases (PT). Experiments presented here show that both ORF 21 and ORF 36 encode GCV kinase activities as demonstrated by GCV phosphorylation and GCV-mediated cell death. In both regards the PT homologue ORF 36 was more active than the TK homologue ORF 21. ORF 21, but not ORF 36, weakly sensitized cells to killing by penciclovir. Neither ORF sensitized cells to killing by (E)-5-(2-bromovinyl)-2'-deoxyuridine.

Quantitation of vaginally administered nonoxynol-9 in premenopausal women.

A feasibility study was performed in 11 healthy nonpregnant premenopausal women to determine a method for collection and recovery of vaginally administered nonoxynol-9. We also determined if nonoxynol-9 could be quantitated in vaginal lavage fluid obtained 2 h after instillation of a standard precoitol dose of a foam formulation of nonoxynol-9. Samples were analyzed in batch using a validated normal phase high-performance liquid chromatography (HPLC) method. Two hours after instillation of one dose of Delfen Contraceptive Foam (100 mg), the quantity of nonoxynol-9 collected ranged from 10.8 to 67.8 mg (mean: 35.4 mg). This corresponds to a recovery of 11.70%, of the administered dose. Quantitation of vaginally administered nonoxynol-9 is both practical and feasible. These data represent a critical first step in the evaluation of the safety and effectiveness of nonoxynol-9-containing products in the prevention of sexually transmitted diseases.

PIP: In clinical trials, nonoxynol-9 has been shown to protect against the transmission of sexually transmitted pathogens. Conversely, there are concerns that frequent use may lead to vaginal irritation and thus increase the risk of transmission of sexually transmitted diseases (STDs), including human immunodeficiency virus (HIV). Nonoxynol-9 is available as a foam, cream, gel, film, and suppository. These routes of administration differ from each other in their total unit dose, ability to irritate genital tissues, rates of dissolution, and ability to coat the vagina. To determine a method for collection and recovery of vaginally administered nonoxynol-9, and thereby facilitate research on the role of nonoxynol-9 in the prevention of HIV, a feasibility study was performed in 11 healthy, premenopausal US women. Also investigated was whether nonoxynol-9 could be quantitated in vaginal lavage fluid obtained 2 hours after instillation of 100 mg of nonoxynol-9 foam (Delfen). The quantity of nonoxynol-9 collected at this time ranged from 10.8-67.8 mg (mean, 35.4 mg), corresponding to a recovery rate of 11-70% of the original dose. Although further studies are needed to optimize methods for nonoxynol-9 recovery from the vagina, this study suggests it is feasible to quantitate nonoxynol-9 after single-dose vaginal administration.

9-[(3-[18F]-fluoro-1-hydroxy-2-propoxy)methyl]guanine ([18F]-FHPG): a potential imaging agent of viral infection and gene therapy using PET.

A no-carrier-added synthesis of 9-[(3-[18F]-fluoro-1-hydroxy-2-propoxy)methyl]-guanine ([18F]-FHPG) is reported. The 9-[(1,3-dihydroxy-2-propoxy)methyl)guanine (DHPG) was converted to 9-[N2,O-bis(methoxytrityl)-3-(tosyl)-2-propoxy-methyl]guanine by treatment with methoxytrityl chloride followed by tosylation. The tosylate was reacted with [18F]-KF in the presence of kryptofix 2.2.2. to produce the 3-fluoro-N2-O-bis-(methoxytrityl) derivative. Removal of the methoxytrityl protecting groups by acid hydrolysis produced [18F]-FHPG. The labeled product was purified by HPLC on a reverse-phase C18 column, and eluted in 9 min with a mobile phase of 5% acetonitrile in water. The radiochemical yield was 7-17%, with an average of 10% in 10 runs (corrected for decay to EOB). The radiochemical purity was > 99%, and specific activities with an average of 526 mCi/mumol were obtained. The synthesis time was 70-80 min, including HPLC purification and determination of radiochemical purity and specific activity.

Determination of the spermicide nonoxynol-9 in vaginal lavage by high-performance liquid chromatography.

A sensitive normal-phase high-performance liquid chromatographic method using a bonded-phase aminosilica column has been developed for the measurement of the spermicide nonoxynol-9 in vaginal lavage fluid. The mean multiple correlation coefficient (r2) for nonoxynol-9 was 0.999 over the calibration range 3.125-50 micrograms/ml for the standards. Quality control samples measured at two different concentration levels gave intra-day precision values (coefficient of variation, C.V.) in the range of 0.61 to 1.63% and the intra-day accuracy values (mean relative error, M.R.E.) in the range of 0.13-0.62%. Inter-day precision and accuracy values from five different calibration standard concentration values ranged from 2.25 to 5.09% C.V. and 4.02 to 7.56% M.R.E. Nonoxynol-9 samples examined for peak area stability at room temperature over a 24-h time period had a M.R.E. of 14.9%. Quality control samples stored at -70 degrees C, and tested after one month by comparison to baseline samples, had a M.R.E. of -10% and 7.53% for the low and high quality control samples, respectively. The method is sensitive and simple, with short runtimes, to enable the processing of numerous samples from a clinical trial.

Anticytomegaloviral activity of methotrexate associated with preferential accumulation of drug by cytomegalovirus-infected cells.

We extend the observation that inhibitors of pyrimidine biosynthesis are active against human cytomegalovirus by demonstrating that methotrexate (MTX) has preferential activity against cytomegalovirus replication. The 50% and 90% inhibitory concentrations of MTX for inhibition of cytomegaloviral DNA replication at 3 days postinfection in MRC-5 cells were 0.05 and 0.2 microM, respectively. No cell toxicity was observed in uninfected confluent cells at the highest concentration tested (1 microM). Under similar conditions (3 days of treatment with 0.2 microM MTX), intracellular dTTP pools were diminished in cytomegalovirus-infected cells (87% decrease relative to untreated infected cells, P < 0.001) but were not reduced in uninfected cells. A potential explanation for the preferential antiviral effect of MTX was that human cytomegalovirus-infected cells preferentially accumulated MTX. Increased intracellular accumulation and increased polyglutamation of MTX were observed in cytomegalovirus-infected cells compared with uninfected cells. Increased uptake of [3H]MTX by cytomegalovirus-infected cells was first observed at 48 h postinfection, with threefold-higher accumulation within infected cells. By 96 h, accumulation had increased to approximately fourfold in comparison with uninfected cells. The uptake of [3H]MTX was saturable and was blocked by addition of unlabelled MTX. Intracellular MTX in infected cells was almost entirely in the polyglutamated form, as demonstrated by thin-layer chromatography, whereas intracellular MTX was almost exclusively in the parent form in uninfected cells.

A randomized trial of the activity and safety of Ro 24-7429 (Tat antagonist) versus nucleoside for human immunodeficiency virus infection. The AIDS Clinical Trials Group 213 Team.

Ro 24-7429, a Tat antagonist, dosed at 75, 150, or 300 mg/day, was compared with nucleoside analogue (zidovudine or didanosine) for 12 weeks in 96 human immunodeficiency virus (HIV)-infected patients to assess safety and activity. The primary adverse effect of Ro 24-7429 was rash, which necessitated treatment discontinuation in 6 of 71 patients. Nucleoside analogue treatment produced an average increase in CD4 cell count of 28 cells/mm3 at week 8 versus a decrease of 27 cells/mm3 in recipients of Ro 24-7429 (P < .001). Serum HIV p24 antigen levels decreased by an average of 111 pg/mL in nucleoside recipients at week 8 compared with an increase of 41 pg/mL in recipients of Ro 24-7429 (P = .007). Nucleoside-treated patients had a mean 0.66 log10 reduction in infectious peripheral blood mononuclear cells, while Ro 24-7429 recipients had a mean 0.02 log10 reduction (P = .02). No dose-response relationships were observed in the Ro 24-7429 groups. In this study, Ro 24-7429 treatment showed no evidence of antiviral activity.

Activity of (S)-1-(3-hydroxy-2-phosphonylmethoxypropyl) cytosine against human cytomegalovirus when administered as single-bolus dose and continuous infusion in in vitro cell culture perfusion system.

HPMPC [(S)-1-(3-hydroxy-2-phosphonylmethoxypropyl)cytosine] is a potent inhibitor of human cytomegalovirus (HCMV) replication as determined by conventional tissue culture methods in which the drug concentration remains constant over time. Previous studies have shown HPMPC to have a long intracellular half-life. Despite its relatively short extracellular half-life, HPMPC might provide significant anti-HCMV activity long after the elimination of the drug by first-order kinetics. We addressed this hypothesis by measuring the activity of HPMPC in a novel cell culture perfusion system. This system allows us to compare the activity of HPMPC when given as a continuous infusion with its activity when given as a single-bolus dose followed by elimination that simulates the drug's in vivo pharmacokinetics. We show that continuous infusions maintaining maximum concentrations (Cmaxs) of 0.05, 0.10, 0.31, and 1.0 micrograms/ml and achieving areas under the drug concentration-time curves (AUCs) of 8.4, 17, 50, and 162 micrograms.h/ml, respectively, result in 27, 56, 63, and 88% inhibition of viral DNA accumulation, respectively, compared with an untreated control. Single-bolus doses achieving Cmaxs of 0.10, 1.25, 3.0, and 7.7 micrograms/ml with an elimination half-life of 20 h achieved AUCs of 2.4, 32, 78, and 138 micrograms.h/ml and resulted in 0, 48, 69, and 87% inhibition of HCMV DNA accumulation. Single-bolus doses achieving Cmaxs of 3.9 and 12 micrograms/ml with an elimination half-life of 6.5 h achieved AUCs of 34 and 105 micrograms.h/ml, respectively, resulting in 15 and 76% inhibition of viral DNA accumulation. Comparison of Cmax-versus-effect curves for these three regimens suggests that maximum concentration is not the only important pharmacokinetic determinant of HPMPC's antiviral activity. Similar comparisons of AUC-versus-effect curves for continuous and bolus dosing suggest that the AUC is an important determinant of antiviral activity for AUCs greater than 100 micrograms . h/ml. We conclude that single-bolus doses of HPMPC potently inhibit HCMV DNA accumulation but that this activity is more heavily influenced by the AUC than the Cmax at the upper end of the AUC range tested. At lower AUCs, some other parameter may be the primary determinant of antiviral activity. Our cell culture perfusion system provides a novel, efficient, and convenient method for addressing questions relating the effects of constantly changing drug concentrations to antiviral effects.

2-Acetylpyridine 5-[(dimethylamino)thiocarbonyl]-thiocarbonohydrazone (1110U81) potently inhibits human cytomegalovirus replication and potentiates the antiviral effects of ganciclovir.

We studied the effects of 2-acetylpyridine 5-[(dimethylamino)thiocarbonyl]-thiocarbonohydrazone (1110U81 or A1110U), a potent inhibitor of the ribonucleotide reductases encoded by herpes simplex virus types 1 and 2 and by varicella-zoster virus, against human cytomegalovirus (HCMV) replication in infected MRC-5 cells. We show that 1110U81 is a potent inhibitor of HCMV DNA replication (50% inhibitory concentration [IC50], 3.6 microM; IC90, 5.6 microM) and also potentiates the effects of ganciclovir (GCV) against HCMV. The IC90 of GCV is reduced from 65 microM when GCV alone is given to 2.8 microM when GCV is combined with 1110U81 at a molar ratio of 1:1.