Phase I study of BIIB028, a selective heat shock protein 90 inhibitor, in patients with refractory metastatic or locally advanced solid tumors

PURPOSE

Heat shot protein 90 (Hsp90) is a ubiquitous molecular chaperone involved in protein folding, activation, and assembly, including key mediators of signal transduction, cell-cycle control, and transcriptional regulation. We conducted a phase I dose-finding and pharmacokinetic/pharmacodynamic study of BIIB028, a prodrug designed to inhibit Hsp90 activity.

EXPERIMENTAL DESIGN

Patients with advanced solid tumors were enrolled and received escalating doses of BIIB028 intravenously twice a week in 21-day cycles (3+3 design). Response was evaluated after two cycles.

RESULTS

Forty-one patients received doses of 6 to 192 mg/m2. The maximum tolerated dose was 144 mg/m2. Dose-limiting toxicities were syncope (n=1) and fatigue (n=1). Common toxicities at least possibly related to drug were grades 1 to 2, including fatigue (46%), diarrhea (44%), nausea (44%), vomiting (29%), hot flushes (29%), and abnormal dreams (17%). The concentration-time curves for day 1 and day 18 for both prodrug and active metabolite (CF2772) showed a negligible difference. There was a dose-dependent increase in plasma exposure for BIIB028 (CF3647) and CF2772 with plasma half-life of 0.5 and 2.1 hours, respectively. Pharmacodynamic analyses showed significant increases in Hsp70 in peripheral blood mononuclear cells and significantly decreased circulating human EGF receptor-2 extracellular domain in all patients who received BIIB028 at dose levels of 48 mg/m2 or more. Stable disease for at least eight cycles (24 weeks) was achieved in 5 (12%) patients (for durations of 6, 6, 8, 12.5, and 19 months).

CONCLUSION

BIIB028 is a well-tolerated molecule that showed target impact and was associated with prolonged stable disease in two patients.

Stage I of a phase 2 study assessing the efficacy, safety, and tolerability of barasertib (AZD1152) versus low-dose cytosine arabinoside in elderly patients with acute myeloid leukemia

BACKGROUND

In this phase 2 study, the authors evaluated the efficacy, safety, and tolerability of the Aurora B kinase inhibitor barasertib compared with low-dose cytosine arabinoside (LDAC) in patients aged ≥ 60 years with acute myeloid leukemia (AML).

METHODS

Patients were randomized 2:1 to receive either open-label barasertib 1200 mg (as a 7-day intravenous infusion) or LDAC 20 mg (subcutaneously twice daily for 10 days) in 28-day cycles. The primary endpoint was the objective complete response rate (OCRR) (complete responses [CR] plus confirmed CRs with incomplete recovery of neutrophils or platelets [CRi] according to Cheson criteria [also requiring reconfirmation of CRi ≥21 days after the first appearance and associated with partial recovery of platelets and neutrophils]). Secondary endpoints included overall survival (OS) and safety.

RESULTS

In total, 74 patients (barasertib, n = 48; LDAC, n = 26) completed ≥1 cycle of treatment. A significant improvement in the OCRR was observed with barasertib (35.4% vs 11.5%; difference, 23.9%; 95% confidence interval, 2.7%-39.9%; P < .05). Although the study was not formally sized to compare OS data, the median OS with barasertib was 8.2 months versus 4.5 months with LDAC (hazard ratio, 0.88; 95% confidence interval, 0.49-1.58; P = .663). Stomatitis and febrile neutropenia were the most common adverse events with barasertib versus LDAC (71% vs 15% and 67% vs 19%, respectively).

CONCLUSIONS

Barasertib produced a significant improvement in the OCRR versus LDAC and had a more toxic but manageable safety profile, consistent with previous studies.

Steady-state pharmacokinetics, cord blood concentrations, and safety of ritonavir-boosted fosamprenavir in pregnancy

Steady-state pharmacokinetics in pregnant women prescribed ritonavir-boosted fosamprenavir (FPV) to prevent HIV transmission were assessed in the second trimester, third trimester, and postpartum. Compared with postpartum, geometric mean amprenavir (APV, FPVs active metabolite) area under the plasma concentration-time curves were 35% lower in the second trimester and 25% lower in the third trimester. Maternal APV concentrations were 9- to 15-fold above the mean APV protein-adjusted 50% inhibitory concentration for wild-type HIV. Median ratio of cord blood/maternal APV levels was 0.27, and all infants were HIV negative. FPV/ritonavir during pregnancy was well tolerated and led to virologic suppression.

Pharmacokinetics and Safety of Fosfluconazole after Single Intravenous Bolus Injection in Healthy Male Japanese Volunteers

This was a single blind, placebo-controlled, escalating single-dose, three-period crossover study using two subject cohorts to investigate the safety, tolerability, and pharmacokinetics in healthy male Japanese subjects after intravenous bolus injection of fosfluconazole 50 to 2000 mg, a phosphate prodrug of fluconazole (FLCZ). Fosfluconazole was rapidly converted to FLCZ with only minor amounts excreted in the urine (less than 4% of the dose). Fosfluconazole had a volume of distribution at the higher doses, which was similar to the extracellular volume in man (0.2 L/kg) and was eliminated with a terminal half-life of 1.5 to 2.5 hours. There was apparent dose proportionality in FLCZ pharmacokinetics. C(max) and AUC of FLCZ appeared to increase proportionally with increasing doses of fosfluconazole. There were no apparent dose-dependent trends in t(max), t(1/2), or mean residence time (MRT) of FLCZ. Bolus injection of fosfluconazole was well tolerated at doses of up to 2000 mg in healthy Japanese subjects.

Successful treatment of recurrent candidemia due to candidal thrombophlebitis associated with a central venous catheter using a combination of fosfluconazole and micafungin

We herein report the case of an 85-year-old woman presenting with right internal jugular vein candidal thrombophlebitis associated with central venous catheters (CTCVC). The infecting agent was Candida albicans, which caused recurrent candidemia five times in total. Micafungin (MCFG) alone was ineffective; however, the combination of MCFG with fosfluconazole (F-FLCZ) successfully treated the patient without a need for any anticoagulant or surgical therapies. To the extent of our knowledge, this is the first report of CTCVC being successfully treated with a combination of F-FLCZ and MCFG. These new antifungal agents have better efficacy, tolerability and bioavailability; therefore, they can be useful alternatives to classical combination therapies such as amphotericin-B and 5-fluorocytosine.

Nanoparticle deposition onto biofilms

We develop a mathematical model of nanoparticles depositing onto and penetrating into a biofilm grown in a parallel-plate flow cell. We carry out deposition experiments in a flow cell to support the modeling. The modeling and the experiments are motivated by the potential use of polymer nanoparticles as part of a treatment strategy for killing biofilms infecting the deep passages in the lungs. In the experiments and model, a fluid carrying polymer nanoparticles is injected into a parallel-plate flow cell in which a biofilm has grown over the bottom plate. The model consists of a system of transport equations describing the deposition and diffusion of nanoparticles. Standard asymptotic techniques that exploit the aspect ratio of the flow cell are applied to reduce the model to two coupled partial differential equations. We perform numerical simulations using the reduced model. We compare the experimental observations with the simulation results to estimate the nanoparticle sticking coefficient and the diffusion coefficient of the nanoparticles in the biofilm. The distributions of nanoparticles through the thickness of the biofilm are consistent with diffusive transport, and uniform distributions through the thickness are achieved in about four hours. Nanoparticle deposition does not appear to be strongly influenced by the flow rate in the cell for the low flow rates considered.

[Effect of aurora kinase B inhibitor AZD1152 in the treatment of cisplatin-resistant ovarian carcinoma]

OBJECTIVE

To investigate whether AZD1152 (AZD), the selective inhibitor of aurora kinase B, may play a role in the treatment of cisplatin-resistant ovarian carcinoma when administrated alone or in combination with cisplatin.

METHODS

Hey (cisplatin-resistant ovarian cancer cell line) cells were analyzed. According to the treatment plan, Hey cells were divided into four groups (AZD group, cisplatin group, AZD + cisplatin group and control group). Methyl thiazolyl tetrazolium (MTT) assay was used to test the cells proliferation, caspase-3/7 activity analysis was used to analyze cells apoptosis, and fluorescence in-situ hybridization (FISH) assay was used to determine the copy the number of chromosome 7 and checked the copy numbers of hTERC gene and C-myc gene.

RESULTS

MTT test showed that proliferation of AZD group was lower than that in control group (P < 0.01). The cells proliferation with the treatment with 10 and 20 nmol/L AZD for 24 hours was (81.4 ± 3.6)% and (81.4 ± 3.6)% respectively, and the cells proliferation for 48 hours was (43.1 ± 2.0)% and (38.5 ± 1.6)% respectively, which was significantly lower than control group (100%, P < 0.01); Treated with the same concentration of AZD, inhibition of proliferation was significantly enhanced as the time extended (P < 0.01). Proliferation in group AZD + cisplatin was lower than that in cisplatin group (P < 0.01) which suggest that there were additive effects after combined AZD with cisplatin. Compared with control group, caspase-3/7 activity in AZD group increased significantly (P = 0.000), and the same results was seen between AZD + cisplatin group and cisplatin group or AZD group (all P < 0.01). Compared with cisplatin group or control group, the copy numbers of hTERC, C-myc and the number of chromosome were significantly increased in AZD group and AZD + cisplat group (all P < 0.05).

CONCLUSIONS

AZD could inhibit ovarian cancer cells proliferation and induce cells apoptosis significantly. AZD alone or in combination with cisplatin may result in the increased cells polyploidy.

Seroprevalence of tick-borne infections in military working dogs in the Republic of Korea

In this study we endeavored to determine the seroprevalence of tick-borne infections in the military working dog (MWD) population in the Republic of Korea (ROK). Our sample population consisted of 182 serum samples from MWDs for 3 different years (1996, 2002, and 2007). In addition, 63 whole blood samples from 2007 were available for polymerase chain reaction (PCR). Serum samples were evaluated by a commercially available enzyme-linked immunosorbent assay (ELISA) and immunofluorescence assay (IFA) for Ehrlichia canis and Anaplasma phagocytophilum, and by ELISA only for Borrelia burgdorferi. PCR amplification of DNA was performed to screen for Ehrlichia canis, E. chaffeensis, E. ewingii, Anaplasma phagocytophilum, A. platys, Borrelia burgdorferi, and Rickettsia rickettsii, as well as Babesia and Theileria species using previously published primers and probes. A total of 56 (30.8%) MWDs were positive by at least one serologic test. Seroprevalences for Anaplasma and Ehrlichia were 4.4% and 0.6% based on the ELISA, and 24.7% and 22.5% based on the IFA, respectively. ELISA testing for Borrelia yielded 2 (1.1%) positive results. In parallel testing using both the ELISA and IFA tests, the percentages of dogs with one or more positive results were 34.1%, 25.9%, and 28.4%, for 1996, 2002, and 2007, respectively. There was no significant differences in seroprevalence based on location, year, breed, or sex of the MWD. There was poor agreement between IFA and ELISA test results. No MWD sample had a positive PCR result. MWDs stationed in Korea had serologic evidence of exposure to several tick-borne pathogens, but PCR testing did not identify any active infections.

Phase 1/2 study to assess the safety, efficacy, and pharmacokinetics of barasertib (AZD1152) in patients with advanced acute myeloid leukemia

The primary objective of this 2-part phase 1/2 study was to determine the maximum-tolerated dose (MTD) of the potent and selective Aurora B kinase inhibitor barasertib (AZD1152) in patients with newly diagnosed or relapsed acute myeloid leukemia (AML). Part A determined the MTD of barasertib administered as a continuous 7-day infusion every 21 days. In part B, the efficacy of barasertib was evaluated at the MTD. In part A, 32 patients were treated with barasertib 50 mg (n = 3), 100 mg (n = 3), 200 mg (n = 3), 400 mg (n = 4), 800 mg (n = 7), 1200 mg (n = 6), and 1600 mg (n = 6). Dose-limiting toxicities (stomatitis/mucosal inflammation events) were reported in the 800 mg (n = 1), 1200 mg (n = 1), and 1600 mg (n = 2) groups. The MTD was defined as 1200 mg. In part B, 32 patients received barasertib 1200 mg. In each part of the study, 8 of 32 patients had a hematologic response according to Cheson AML criteria. The most commonly reported grade ≥ 3 events were febrile neutropenia (n = 24) and stomatitis/mucosal inflammation (n = 16). We concluded that the MTD of barasertib is 1200 mg in patients with relapsed or newly diagnosed AML. Toxicity was manageable and barasertib treatment resulted in an overall hematologic response rate of 25%. This study is registered at www.ClinicalTrials.gov as NCT00497991.

Interactions between buprenorphine and the protease inhibitors darunavir-ritonavir and fosamprenavir-ritonavir

BACKGROUND

This study examined drug interactions between buprenorphine, a partial opioid agonist used for opioid dependence treatment and pain management, and the protease inhibitors (PIs) darunavir-ritonavir and fosamprenavir-ritonavir.

METHODS

The pharmacokinetics of buprenorphine and its metabolites and symptoms of opioid withdrawal or excess were compared in opioid-dependent, buprenorphine-naloxone-maintained, human immunodeficiency virus (HIV)-negative volunteers (11 for darunavir-ritonavir and 10 for fosamprenavir-ritonavir) before and after 15 days of PI administration. PI pharmacokinetics and adverse effects were compared between the buprenorphine-maintained participants and an equal number of sex-, age-, race-, and weight-matched, healthy, non-opioid-dependent volunteers who received darunavir-ritonavir or fosamprenavir-ritonavir but not buprenorphine.

RESULTS

There were no significant changes in buprenorphine or PI plasma levels and no significant changes in medication adverse effects or opioid withdrawal. Increased concentrations of the inactive metabolite buprenorphine-3-glucuronide suggested that darunavir-ritonavir and fosamprenavir-ritonavir induced glucuronidation of buprenorphine.

CONCLUSIONS

Dose adjustments are not likely to be necessary when buprenorphine and darunavir-ritonavir or fosamprenavir-ritonavir are coadministered for the treatment of opioid dependence and HIV disease.

DNA polymerase β as a novel target for chemotherapeutic intervention of colorectal cancer

Chemoprevention presents a major strategy for the medical management of colorectal cancer. Most drugs used for colorectal cancer therapy induce DNA-alkylation damage, which is primarily repaired by the base excision repair (BER) pathway. Thus, blockade of BER pathway is an attractive option to inhibit the spread of colorectal cancer. Using an in silico approach, we performed a structure-based screen by docking small-molecules onto DNA polymerase β (Pol-β) and identified a potent anti-Pol-β compound, NSC-124854. Our goal was to examine whether NSC-124854 could enhance the therapeutic efficacy of DNA-alkylating agent, Temozolomide (TMZ), by blocking BER. First, we determined the specificity of NSC-124854 for Pol-β by examining in vitro activities of APE1, Fen1, DNA ligase I, and Pol-β-directed single nucleotide (SN)- and long-patch (LP)-BER. Second, we investigated the effect of NSC-124854 on the efficacy of TMZ to inhibit the growth of mismatch repair (MMR)-deficient and MMR-proficient colon cancer cell lines using in vitro clonogenic assays. Third, we explored the effect of NSC-124854 on TMZ-induced in vivo tumor growth inhibition of MMR-deficient and MMR-proficient colonic xenografts implanted in female homozygous SCID mice. Our data showed that NSC-124854 has high specificity to Pol-β and blocked Pol-β-directed SN- and LP-BER activities in in vitro reconstituted system. Furthermore, NSC-124854 effectively induced the sensitivity of TMZ to MMR-deficient and MMR-proficient colon cancer cells both in vitro cell culture and in vivo xenograft models. Our findings suggest a potential novel strategy for the development of highly specific structure-based inhibitor for the prevention of colonic tumor progression.

Phase 2, randomized, double-blind, dose-ranging study evaluating the safety, tolerability, population pharmacokinetics, and efficacy of oral torezolid phosphate in patients with complicated skin and skin structure infections

Torezolid (TR-700) is the active moiety of the prodrug torezolid phosphate ([TP] TR-701), a second-generation oxazolidinone with 4- to 16-fold greater potency than linezolid against Gram-positive species including methicillin-resistant Staphylococcus aureus (MRSA). A double-blind phase 2 study evaluated three levels (200, 300, or 400 mg) of oral, once-daily TP over 5 to 7 days for complicated skin and skin structure infections (cSSSI). Patients 18 to 75 years old with cSSSI caused by suspected or confirmed Gram-positive pathogens were randomized 1:1:1. Of 188 treated patients, 76.6% had abscesses, 17.6% had extensive cellulitis, and 5.9% had wound infections. S. aureus, the most common pathogen, was isolated in 90.3% of patients (139/154) with a baseline pathogen; 80.6% were MRSA. Cure rates in clinically evaluable patients were 98.2% at 200 mg, 94.4% at 300 mg, and 94.4% at 400 mg. Cure rates were consistent across diagnoses, regardless of lesion size or the presence of systemic signs of infection. Clinical cure rates in patients with S. aureus isolated at baseline were 96.6% overall and 96.8% for MRSA. TP was safe and well tolerated at all dose levels. No patients discontinued treatment due to an adverse event. Three-stage hierarchical population pharmacokinetic modeling yielded a geometric mean clearance of 8.28 liters/h (between-patient variability, 32.3%), a volume of the central compartment of 71.4 liters (24.0%), and a volume of the peripheral compartment of 27.9 liters (35.7%). Results of this study show a high degree of efficacy at all three dose levels without significant differences in the safety profile and support the continued evaluation of TP for the treatment of cSSSI in phase 3 trials.

Assessment of acetylcholinesterase activity in Clarias gariepinus as a biomarker of organophosphate and carbamate exposure

The objective of this study was to investigate the response of acetylcholinesterase (AChE) activities in Clarias gariepinus in response to Organophosphates (Ops) and carbamate exposure. The AChE activities were determined in plasma, and eye and brain homogenates of unexposed and exposed fish using Ellman's method and 5,5'-dithiobis-2-nitrobenzoic acid (DTNB) chromophore. The baseline AChE activities in plasma, eyes and brain tissues in unexposed fish were comparable between males and females (P > 0.05). Concentrations of pesticides that inhibited 50% (IC(50)) of AChE activities in brain homogenates following in vitro exposures were 0.003, 0.03, 0.15, 190, 0.2, 0.003 and 0.002 microM for carbaryl, chlorfenvinphos, diazinon, dimethoate, fenitrothion, pirimiphosmethyl and profenofos, respectively. The in vivo dose-effect relationships were assessed using chlorfenvinphos and carbaryl at different concentrations that ranged from 0.0003 to 0.06 microM and 0.0005 to 0.05 microM, respectively. Acetylcholinesterase activities were comparable in plasma, and eye and brain homogenates from control and carbaryl-exposed fish. Following exposure of fish to chlorfenvinphos at concentrations above 0.03 microM, a significant inhibition of AChE activities in plasma (84%) and eye homogenate (50%) was observed. The AChE activities in brain homogenate were comparable between chlorfenvinphos-exposed fish and controls. Because carbaryl cause reversible inhibition of AChE activities was found to be more potent than chlorfenvinphos that cause irreversible inhibition following in vitro exposure. Contrary, carbaryl was less potent than chlorfenvinphos after in vivo exposure possibly due to more rapid biotransformation of carbaryl than chlorfenvinphos. Findings from this study have demonstrated that inhibition of AChE activity in C. gariepinus is a useful biomarker in assessing aquatic environment contaminated by anticholinesterases.

Impact of low abundance HIV variants on response to ritonavir-boosted atazanavir or fosamprenavir given once daily with tenofovir/emtricitabine in antiretroviral-naive HIV-infected patients

Population genotyping (PG) can underestimate resistance if resistance-containing low abundance variants go undetected. PG and clonal analysis (CA) results were compared in virologic failures (VFs) from a 48-week clinical trial that evaluated once-daily fosamprenavir/ritonavir (FPV/r) 1400 mg/100 mg or atazanavir/ritonavir (ATV/r) 300 mg/100 mg, each combined with tenofovir/emtricitabine, in antiretroviral-naive patients. VF was defined as confirmed HIV-1 RNA > or =400 copies/ml at > or =24 weeks or viral rebound >400 copies/ml any time following viral suppression. All patients had baseline PG. One hundred and six patients enrolled (53/arm). Baseline resistance mutations were more prevalent in patients receiving FPV/r (10/53) than ATV/r (3/53). Seven patients (7%) were VFs-four on FPV/r and three on ATV/r. In the four FPV/r-treated VFs, baseline HIV TAMs combinations and/or PI mutations were detected in one by PG at VF (RT: L210W + T215C; PR: M46I + L76V) and three others by CA alone (RT: L210W + T215Y; RT: M41L; RT: K65R + K70R; PR: I47V); all four had study drug-associated mutations (CA detecting more HIV-1 resistance mutations than PG). In the three ATV/r VFs, no baseline drug-associated mutations were detected by PG; for one patient CA detected RT: K65R; PR: I84V. Phylogenetic analysis revealed tight clustering for FPV/r-treated VFs with highly related clones, whereas HIV-1 from ATV/r-treated VFs had no outgrowth from baseline of low abundance resistance-containing variants. In conclusion, low-abundance HIV resistance-containing variants were detected in baseline samples from patients with VF. The archived viruses that reemerged under selection pressure and acquired additional mutations were found primarily in patients in the FPV/r arm. Despite this and a baseline resistance imbalance between the two arms, FPV/r and ATV/r provided similar virologic suppression through 48 weeks; however, these findings highlight the necessity for the development of quick and inexpensive methods for detection of minority species to better guide therapy selection.

Pharmacokinetics of DA-7218, a new oxazolidinone, and its active metabolite, DA-7157, after intravenous and oral administration of DA-7218 and DA-7157 to rats

DA-7218 (a prodrug of DA-7157), a new oxazolidinone, was hydrolysed via phosphatase to form its active metabolite, DA-7157, in rats. The pharmacokinetic parameters of DA-7218 and DA-7157 were evaluated after intravenous (5, 10 and 20 mg kg−1) and oral (20, 50 and 100 mg kg−1) administration of DA-7218 to rats. DA-7218 and DA-7157 exhibited dose-proportional pharmacokinetics after both intravenous and oral administration of DA-7218 to rats. The stability of DA-7218 and DA-7157, blood partition of DA-7157, and the plasma protein binding of DA-7157 were also evaluated. DA-7218 was unstable in rat blood, plasma, bile and liver homogenates, but DA-7157 was stable, suggesting that DA-7218 is hydrolysed via phosphatase. DA-7157 rapidly reached equilibrium between plasma and blood cells, and the mean equilibrium plasma-to-blood cells ratio was 3.18, indicating that binding of DA-7157 to blood cells was not considerable. The protein binding of DA-7157 in fresh rat plasma was 93.4%.

[Comparison of micafungin and fosfluconazole as prophylaxis for invasive fungal infection during neutropenia in children undergoing chemotherapy and hematopoietic stem cell transplantation]

Invasive fungal infection (IFI) is a serious complication of chemotherapy for hematological malignancies and autologous/allogeneic hematopoietic stem cell transplantation in children and shows a high mortality rate. We performed a randomized trial comparing micafungin (MCFG), a new anti-fungal agent, with fosfluconazole, a prodrug of fluconazole (FF) conventionally used as a prophylactic agent, for prophylaxis against IFI. Cefpirome was administered as prophylaxis against bacterial infection, and meropenem+minocycline as an empiric window therapy for febrile neutropenia. MCFG 2 mg/kg/day (max 100 mg/day) and FF 10 mg/kg/day (max 400 mg/day) were both safe and effective (event free ratio of IFI, MCFG 94.4% vs FF 94.3%) without significant difference. Thus, MCFG is safe and can be used for prophylaxis against IFI in children.

Most Common Intoxication in Nephrology Ward Organophosphate Poisoning

OBJECTIVES

In Taiwan, the widespread use of organophosphates (OPs) in agricultural and household environments results in numerous OP poisoning. To better understand the clinical significance of associated parameters on respiratory failure and patient outcome, we evaluate patients admitted to the Nephrology ward in our hospital with OP intoxication.

PATIENTS AND METHODS

Over a period of 2 years, a total of 42 consecutive patients with OP poisoning admitted to the nephrology ward or the Intensive Care Unit of Chang-Gung Memorial Hospital were the subjects in the study. The diagnosis of poisoning was based on history of ingestion and characteristic clinical features of anticholinesterase agent poisoning. Prior to treatment, all symptoms recorded at emergency room and blood samples for blood chemistry including plasma amylase and plasma acetyl-cholinesterase were collected from each patient immediately after the admission.

RESULTS

As clinical manifestations of OP show, nausea and vomiting and salivation were the leading manifestations, 45.2% and 33.3%, respectively. Patients who developed respiratory failure were older than those who did not (54.3+/-6.9 vs. 43.1+/-5.6, p<0.05). The dosage of atropine administered for treatment was significantly higher in the patient group with respiratory failure compared to those without respiratory failure (29.7+/-14.5 vs. 9.1+/-10.2, p<0.05). Plasma amylase level of the patient group with respiratory failure was significantly higher than those without respiratory failure (436.1+/-87.1 vs. 181.3+/-29.6, p<0.01). Of course, mean days of hospitalization in the respiratory failure group are significantly longer than the other group (12.1+/-2.1 vs. 5.4+/-1.9, p<0.05). Based on univariant analysis, bradycardia, hypotension, fasciculation and coma were significant factors associated with respiratory failure. The dose of atropine administered for treatment was significantly higher in the oral exposure group compared to nonoral exposure group (23.6+/-12.6 vs. 10.6+/-6.4, p<0.05). The same is true for the pralidoxime treatment (9.6+/-1.9 vs. 5.3+/-1.4, p<0.05). As for mean days of hospitalization (11.6+/-3.9 vs. 6.4+/-2.1, p<0.05) and fatality (2 vs. 0, p<0.05), those of oral exposure patients were significantly longer and higher than those with nonoral exposure.

CONCLUSIONS

We demonstrate that elevated plasma amylase concentration was related to the development of respiratory failure in OP intoxication. It also provided us various important risk factors to identify those patients with OP poisoning who would ultimately require ventilatory support.

The effects of chronic inorganic and organic phosphate exposure on bactericidal activity of the coelomic fluid of the sea urchin Lytechinus variegatus (Lamarck) (Echinodermata: Echinoidea)

The sea urchin Lytechinus variegatus can survive chronic exposure to sodium phosphate (inorganic phosphate) concentrations as high as 3.2 mg L-1, and triethyl phosphate (organic phosphate) concentrations of 1000 mg L-1. However, chronic exposure to low (0.8 mg L-1 inorganic and 10 mg L-1 organic phosphate), medium (1.6 mg L-1 inorganic and 100 mg L-1 organic phosphate) or high (3.2 mg L-1 inorganic and 1000 mg L-1 organic phosphate) sublethal concentrations of these phosphates inhibit bactericidal clearance of the marine bacterium Vibrio sp. Bacteria were exposed to coelomic fluid collected from individuals maintained in either artificial seawater, or three concentrations of either inorganic phosphate or organic phosphate. Sterile marine broth, natural seawater and cell free coelomic fluid (cfCF) were employed as controls. Bacterial survival indices were measured at 0, 24 and 48 h periods once a week for four weeks. Bacteria were readily eliminated from the whole coelomic fluid (wCF) of individuals maintained in artificial seawater. Individuals maintained in inorganic phosphates were able to clear bacteria following a two week exposure period, while individuals maintained at even low concentrations of organic phosphates failed to clear all bacteria from their coelomic fluid. Exposure to phosphates represses antimicrobial defenses and may ultimately compromise survival of L. variegatus in the nearshore environment.

Respiratory failure induced by acute organophosphate poisoning in rats: effects of vagotomy

Acute organophosphate (OP) poisoning causes respiratory failure through two mechanisms: central apnea and pulmonary dysfunction. The vagus nerve is involved in both the central control of respiratory rhythm as well as the control of pulmonary vasculature, airways and secretions. We used a rat model of acute OP poisoning with and without a surgical vagotomy to explore the role of the vagus in OP-induced respiratory failure. Dichlorvos (2,2-dichlorovinyl dimethyl phosphate) injection (100mg/kg subcutaneously, 3 x LD50) resulted in progressive hypoventilation and apnea in all animals, irrespective of whether or not the vagi were intact. However, vagotomized animals exhibited a more rapidly progressive decline in ventilation and oxygenation. Artificial mechanical ventilation initiated at onset of apnea resulted in improvement in oxygenation and arterial pressure in poisoned animals with no difference between vagus intact or vagotomized animals. Our observations suggest that vagal mechanisms have a beneficial effect during the poisoning process. We speculate that vagally mediated feedback signals from the lung to the brainstem serve as a modest protective mechanism against central respiratory depressive effects of the poison and that bulbar-generated efferent vagal signals do not cause sufficient pulmonary dysfunction to impair pulmonary gas exchange.

Optimal fosamprenavir regimen to prevent lipid abnormalities

We report our experience on the impact of different fosamprenavir boosted regimens on plasma lipid levels in 48 naive monoinfectd- HIV-seropositive patients. Eighteen months after starting antiretroviral therapy (ART), all patients showed a good immuno-virological response, with no statistically significant differences among the three groups; no changes in ART regimens were necessary and no adverse events were reported. On the contrary, a statistically significant difference among the three groups of patients was observed in cholesterol and triglyceride levels, since higher levels of cholesterol (including LDLs) and triglycerides were observed in patients taking the higher dose of ritonavir. (www.actabiomedica.it)

[Clinical efficacies of antifungal injections]

The incidence of fungal infection is increasing. Amphotericin B has been the gold standard in antifungal chemotherapy for a long time. Within the past few years, three novel antifungal agents have been approved to evaluate the clinical benefits in Japan. Liposomal amphotericin B is developed to reduce toxicities of amphotericin B. Voriconazole, a kind of the new broad-spectrum triazoles, is recommended for the primary treatment of invasive aspergillosis. Micafungin is a new lipopeptide antifungal agent of the echinocandin class. These drugs might provide an individualized and more effective antifungal therapy for each patient. On the other hand, we need to establish a new standard therapy.

Physicochemical characteristics andin vivodeposition of liposome-encapsulated tea catechins by topical and intratumor administrations

Tea polyphenols, including (+)-catechin, (-)-epicatechin, and (-)-epigallocatechin-3-gallate (EGCG), have been shown to possess potent antioxidant and anticancer activities. The aim of this study was to evaluate the possibility of using liposomes for the local delivery, including skin and tumor deposition, of these polyphenols. Liposomes containing egg phosphatidylcholine, cholesterol, or anionic species were prepared by a solvent evaporation method and then were subjected to a probe sonicator. The size, zeta potential and entrapment efficiency of these liposomal formulations were determined to provide correlations with results from a subsequent in vivo study. The release rate study showed that inclusion of an anionic species, such as deoxycholic acid (DA) or dicetyl phosphate (DP), increased the permeability of the lipid bilayers, leading to the rapid release of these formulations. No significant increase in skin deposition of catechins was observed after topical application of liposomes. On the other hand, a greater amount of catechins were delivered into the solid tumor by liposomes than by the aqueous solution. The drug release rate and vesicle size of liposomes may influence drug deposition in tumor tissues. The isomers, (+)-catechin and (-)-epicatechin, showed different physicochemical properties in liposomes and for local deposition in the skin and tumor. Finally, the presence of gallic acid ester in the structure of EGCG significantly increased the tissue uptake of catechins.