Identification and molecular characterization of a novel protein Saglin as a target of monoclonal antibodies affecting salivary gland infectivity of Plasmodium sporozoites

Molecular mechanisms underlying the interaction between malarial sporozoites and putative receptor(s) on the salivary glands of Anopheles gambiae remain largely unknown. In previous studies, a salivary gland protein of ~100 kDa was identified as a putative target based on recognition of the protein by a monoclonal antibody (mAb) 2A3 that caused a >/= 70% reduction in the average number of sporozoites per infected salivary gland when fed to mosquitoes. Using affinity purification we purified the target of this mAb from extracts of female A. gambiae salivary glands and it was found to be a novel protein by tandem mass spectrometric analysis. Biochemical and molecular characterization of the 100 kDa protein showed that this molecule, designated Saglin, exists as a disulphide-bonded homodimer of 50 kDa subunits. The ability to form homodimers was retained even in the recombinant Saglin expressed in mammalian cells (HEK293). The amino acid sequence of Saglin contains a signal peptide suggesting that Saglin is a secreted protein. If Saglin is indeed involved in the process of invasion of A. gambiae salivary glands by sporozoites of Plasmodium, it could provide a novel target for future investigations aimed at interruption of malaria transmission.

Sequential therapy using high-dose esomeprazole-amoxicillin followed by gatifloxacin for Helicobacter pylori infection

BACKGROUND

The success rate of current anti-Helicobacter pylori triple therapies in now generally 80% or less. Sequential therapy has proved superior.

AIM

To test a new sequential therapy for H. pylori eradication.

METHODS

This was a pilot study of a sequential therapy consisting of 40 mg of esomeprazole and 1 g amoxicillin t.d.s., for 12 days. On days 6 through 12 gatifloxacin (400 mg in the morning) was added. Outcome was accessed 4 or more weeks after ending antibiotic therapy. Both naive and treatment failures were eligible.

RESULTS

Thirty patients were entered in the study. One was lost to follow-up and one stopped early because of side effects. The success rate intention-to-treat was 80% (95% CI: 61-92%). The per-protocol eradication rate was 85.7% (95% CI: 67-95%); two of the four failures had pre-treatment gatifloxacin-resistant H. pylori. Side effects were reported by 13 patients (46%) and were generally mild with diarrhoea being most common (n = 6). Only one patient stopped medicine because of side effects of dizziness (severe) and diarrhoea (mild).

CONCLUSIONS

Sequential therapy using the combination of a high dose of proton-pump inhibitor and amoxicillin followed gatifloxacin was effective, but pre-treatment susceptibility testing may become necessary as fluoroquinolone resistance increases.

Phase I study of ON-01910.Na, a novel cell cycle inhibitor in adult patients with solid tumors

13026

Background: ON-1910.Na is a new chemical entity, novel cell cycle inhibitor which arrests cells in G2/M, affects phosphorylation of several regulatory kinases and lacks cross resistance to other standard chemotherapy agents. This is a first-in-man Phase I dose escalation study to determine the dose limiting toxicities, recommended Phase II dose, and pharmacokinetic (PK) profile, and to document any antitumor activity of ON-01910.Na. Methods: Patients had histologically confirmed solid tumors refractory to standard therapy. ON-1910.Na, formulated as a solution in PEG400, was administered as a 2-hour infusion on days 1, 4, 8, 11, 15, and 18 followed by a 10 day observation period for a total of 28 days per cycle. The initial dose was 80 mg and was escalated using an accelerated titration schedule; one patient was treated per cohort until grade 2 toxicity was documented. A dose confirmation cohort of up to 12 patients will be treated at the maximun tolerated dose (MTD). A comprehensive PK study was performed on days 1 and 15 of the first cycle, plus trough samples were collected. Results: Thirteen patients (7F, 6M; ages 46–73) have received 20 cycles. Dose levels of 80, 160, 320, 480, 800, 1280, 2080, and 3120 mg were evaluated in 8 patients, and a further dose of 4370 mg has been evaluated in 5 patients. Toxicities have been anemia (2 G1, 1 G2), leucopenia (1 G1, 1 G2), hyperglycemia (2 G1), elevated AST/ALT (1 G1, 1 G2), nausea (3 G1), diarrhea (3 G1), skeletal pain (5 G1, 1 G2), abdominal pain (2 G1), tumor pain (1 G2), and fatigue (3 G1, 1 G2), and have clustered at the latter 3 dose levels. PK analysis shows increasing ON-1910.Na exposure with increasing doses. ON-1910.Na has a low clearance (13 L/h), long half-life (20 h), distribution in excess of blood volume (58 L) and PK parameters are similar on days 1 and 15. Approximately 3-fold and 5-fold inter-subject variation in ON-1910.Na clearance was observed on days 1 and 15, respectively. No antitumor activity has been documented by standard criteria. Conclusions: Dose escalation is continuing.

[Table: see text]

Helicobacter pylori outer membrane proteins and gastroduodenal disease

BACKGROUND AND AIMS

A number of Helicobacter pylori outer membrane proteins (OMPs) undergo phase variations. This study examined the relation between OMP phase variations and clinical outcome.

METHODS

Expression of H pylori BabA, BabB, SabA, and OipA proteins was determined by immunoblot. Multiple regression analysis was performed to determine the relation among OMP expression, clinical outcome, and mucosal histology.

RESULTS

H pylori were cultured from 200 patients (80 with gastritis, 80 with duodenal ulcer (DU), and 40 with gastric cancer). The most reliable results were obtained using cultures from single colonies of low passage number. Stability of expression with passage varied with OipA > BabA > BabB > SabA. OipA positive status was significantly associated with the presence of DU and gastric cancer, high H pylori density, and severe neutrophil infiltration. SabA positive status was associated with gastric cancer, intestinal metaplasia, and corpus atrophy, and negatively associated with DU and neutrophil infiltration. The Sydney system underestimated the prevalence of intestinal metaplasia/atrophy compared with systems using proximal and distal corpus biopsies. SabA expression dramatically decreased following exposure of H pylori to pH 5.0 for two hours.

CONCLUSIONS

SabA expression frequently switched on or off, suggesting that SabA expression can rapidly respond to changing conditions in the stomach or in different regions of the stomach. SabA positive status was inversely related to the ability of the stomach to secrete acid, suggesting that its expression may be regulated by changes in acid secretion and/or in antigens expressed by the atrophic mucosa.

Treatment of asymptomatic carotid artery disease: Similar early outcomes after carotid stenting for high-risk patients and endarterectomy for standard-risk patients

BACKGROUND

The role of carotid angioplasty and stenting (CAS) in the treatment of asymptomatic patients with carotid disease remains controversial. The purpose of this report is to compare outcomes in asymptomatic patients treated with CAS and carotid endarterectomy (CEA). This was the initial experience performing CAS for most of the surgeons. For comparison, we also report our outcomes in standard-risk patients treated concurrently with CEA during the same period of time.

METHODS

A retrospective, nonrandomized review of asymptomatic patients undergoing CEA or CAS at Washington University Medical Center in St. Louis was done. Patients with >70% asymptomatic carotid stenosis treated between September 2003 and April 2005 were identified. CEA was the first therapeutic consideration in all patients. CAS was reserved for high-risk patients. Thirty-day outcomes of stroke or death were recorded. During this time interval, 248 patients were treated including with 93 CAS and with 145 CEA. Symptomatic or clinically detected adverse outcomes such as myocardial infarction (MI), arrhythmia, renal failure, or pulmonary complications were noted but were not the primary end points of this review. This study addresses only the periprocedural outcomes of CEA and CAS in asymptomatic patients. No data >30-day follow-up are included.

RESULTS

During this period, 93 CAS and 145 CEA procedures were done in asymptomatic patients. Patient characteristics in both groups were similar. Carotid protection devices were used in 91.4% of CAS patients. The results in the CAS group showed one death (1.1%) and one stroke (1.1%). In the CEA group, three strokes occurred (2.1%, P = 0.9999), one associated with death (0.7%, P = 0.9999). The CAS group had 1.34 +/- 0.83 risk factors vs 0.39 +/- 0.58 in the CEA group (P < .0001). Median CAS and CEA length of stay was 1 day.

CONCLUSIONS

CAS for asymptomatic carotid stenosis demonstrated equivalent outcomes compared with CEA, despite CAS being reserved for use in a disadvantaged subset of high-risk patients owing to anatomic risk factors or medical comorbidities. These results suggest CAS should be considered a reasonable treatment option in the high-risk but asymptomatic patient. Enthusiasm for CAS should be tempered by the recognition that long-term outcomes in CAS-treated asymptomatic patients remain unknown.

Radioprotective effect of abana, a polyherbal drug following total body irradiation

Effects of 20 mg/kg body weight of abana (ABE) on radiation-induced sickness and mortality in mice exposed to 7 Gy to 12 Gy of gamma irradiation were studied. Treatment of mice with abana 1 h before irradiation delayed the onset of mortality and reduced the symptoms of radiation sickness when compared with the non-drug treated irradiated controls (double distilled water, DDW). Abana provided protection against both the gastrointestinal and haemopoietic deaths. However, animals of both the ABE+irradiation and DDW+irradiation groups did not survive up to 30 days post-irradiation beyond 11 Gy irradiation. The LD(50/30) was found to be 8.5 Gy for the DDW+irradiation group and 10.3 Gy for ABE+irradiation group. The administration of abana resulted in an increase in radiation tolerance by 1.8 Gy, and the dose modification factor (DMF) was found to be 1.2. The irradiation of animals resulted in a dose dependent elevation in lipid peroxidation, and a reduction in glutathione (GSH) concentration on day 31 post-irradiation. Treatment of mice with abana before irradiation caused a significant depletion in lipid peroxidation followed by a significant elevation in GSH concentration in the liver of mice at day 31 post-irradiation. Abana scavenged (*)OH, DPPH, ABTS(*+) and NO(*) in a concentration dependent manner in vitro. Our results indicate that the radioprotective activity of abana may be due to free radical scavenging and increased GSH level in irradiated mice.

Potentiation of paclitaxel cytotoxicity in lung and esophageal cancer cells by pharmacologic inhibition of the phosphoinositide 3-kinase/protein kinase B (Akt)-mediated signaling pathway

BACKGROUND

Constitutive activation of the phosphoinositide 3-kinase/protein kinase B survival signal transduction pathway influences the intrinsic chemoresistance of cancer cells. This study evaluates the effect of LY294002, a pharmacologic inhibitor of phosphoinositide 3-kinase, on the sensitivity of lung and esophageal cancer cells to paclitaxel (Taxol) in vitro. Materials and methods Cell viability and apoptosis of cancer cells treated with paclitaxel + LY294002 combinations were quantitated by methyl-thiazol-diphenyl-tetrazolium and terminal deoxynucleotidyltransferase-mediated dUTP nick-end labeling-based ApoBrdU assays, respectively. The effect of LY294002-mediated phosphoinositide 3-kinase inhibition on protein kinase B (Akt) activation and nuclear factor-kappaB signaling was determined by Western blot analysis. Nuclear factor-kappaB transcription activity in cultured cancer cells either at baseline or after treatments with LY294002 or BAY11-0782 (a pharmacologic inhibitor of nuclear factor-kappaB) was determined by the nuclear factor-kappaB-Luciferase reporter system.

RESULTS

A 4- to more than 20-fold reduction of paclitaxel IC(50) values was observed in cancer cells treated with paclitaxel + LY294002 combinations. This was paralleled with synergistic induction of apoptosis. LY294002 treatment caused a significant dose-dependent inhibition of protein kinase B (Akt) activation and suppression of nuclear factor-kappaB transcriptional activity that was accompanied by elevation of IkappaB, the intrinsic inhibitor of nuclear factor-kappaB, and concomitant reduction of nuclear factor-kappaB-regulated antiapoptotic proteins cIAP1, cIAP2, and BclXL. Direct inhibition of nuclear factor-kappaB activity by BAY11-0782 also resulted in profound enhancement of paclitaxel sensitivity and paclitaxel-mediated induction of apoptosis in lung and esophageal cancer cells.

CONCLUSION

LY294002-mediated inhibition of the phosphoinositide 3-kinase/protein kinase B-dependent survival pathway with secondary suppression of nuclear factor-kappaB transcriptional activity was associated with enhancement of paclitaxel cytotoxicity in lung and esophageal cancer cells. Direct inhibition of nuclear factor-kappaB by BAY11-0782 also sensitized these cancer cells to paclitaxel, indicating that nuclear factor-kappaB may be the crucial intermediary step connecting phosphoinositide 3-kinase/protein kinase B (Akt) to the intrinsic susceptibility of cancer cells to chemotherapeutic agents.

Analysis of Fusarium Graminearum Mycotoxins in Different Biological Matrices by LC/MS

The purpose of this study was to develop an LC/MS assay to accurately detect three mycotoxins produced by Fusarium graminearum in various matrices. Using different LC conditions, deoxynivalenol (DON), 15-acetyldeoxynivalenol (15-ADON), and zearalenone (ZEN) were detected in four different matrices (fungal liquid cultures, maize grain, insect larvae and pig serum). The sensitivity of MS detection allowed us to detect concentrations as low as 8 ppb of DON and 12 ppb of ZEN. A very small quantity of matrix was therefore necessary for successful analysis of these toxins and a variety of experimental situations were successfully investigated using this technique. Production of 15-ADON and butenolide was monitored in a liquid culture of F. graminearum under controlled conditions. Using simple extraction procedures, the differential accumulation of DON and 15-ADON was followed in inoculated maize genotypes varying in susceptibility to F. graminearum. Toxicokinetic studies were carried out with maize insect pests reared continually on artificial diets containing ZEN and suggested that larvae may possess the ability to degrade ZEN. Finally, persistence of DON was assessed in pigs fed diet supplemented with DON, results indicated that DON accumulates quickly in pig blood and then levels decline progressively for 12 hours thereafter. The LC/MS study reported here is very useful and flexible for the detection of these mycotoxins in different media and at very low concentrations.

Effect of 3M™ Coban™ Self-Adherent Wraps on Edema and Function of the Burned Hand: A Case Study

Edema and limited function are common acute problems associated with hand burns. This case study examined the effects of 3M Coban Self-Adherent Wraps on edema and function in a 59-year-old male (46% TBSA flame injury) with newly skin grafted dorsally burned hands. At the time of each dressing change, circumferential measurements were taken of both hands and weekly active range of motion and grip strength measurements were recorded. The nine-hole peg test was used to appraise dexterity. During the 4-week study period, there was less edema, greater active range of motion and grip strength, and greater dexterity in the hand with 3M Coban Self-Adherent Wraps as compared with the control hand. This case study suggests that 3M Coban Self-Adherent Wraps were effective in reducing edema in the skin-grafted hand after skin grafting. It further appeared that the reduced edema may have contributed to improved hand function and that 3M Coban Self-Adherent Wraps as a compressive dressing do not impede hand function

Interleukin-2 receptors and interleukin-2-mediated signaling in myelin: activation of diacylglycerol kinase and phosphatidylinositol 3-kinase

Myelin was previously shown to possess neurotransmitter and cytokine receptors that trigger well-defined signaling mechanisms within the multilamellar structure. The present study reveals the presence of an interleukin-2 (IL-2) receptor in isolated mouse CNS myelin that responds to recombinant mouse IL-2 by activating diacylglycerol kinase (DAGK) and phosphoinositide 3-kinase (PI3K); additional evidence suggests participation by protein tyrosine kinase. Activation of myelin DAGK by IL-2 occurred in brain stem tissue mince and was blocked by chelerythrin chloride, indicating an essential role for myelin-localized protein kinase C. Two inhibitors of PI3K, wortmannin and LY294002, blocked endogenous PI3K as well as that enhanced by IL-2. Activation of PI3K by IL-2 was also blocked by tyrphostin A25, a selective inhibitor of PTK, suggesting activation of the latter by IL-2 is upstream to PI3K activation. This reaction resulted in tyrosine phosphorylation of a protein tentatively identified as the p85 subunit of PI3K. Developmental changes were noted in that receptor density and signaling activity were robust during the period of rapid myelination and declined rapidly thereafter.

The safety and tolerability of daily infergen plus ribavirin in the treatment of naíïve chronic hepatitis C patients

The treatment of chronic hepatitis C patients was enhanced when the combination of interferon alfa-2b and ribavirin was shown to be safe and more effective than interferon monotherapy. To date, no published reports have addressed the use of consensus interferon (CIFN) when combined with ribavirin. We conducted a pilot study to compare the safety and tolerability of daily CIFN plus ribavirin to CIFN monotherapy for the initial treatment of chronic hepatitis C patients. Forty subjects were randomized to two treatment groups; CIFN 9 microg daily, or CIFN 9 microg daily plus ribavirin 1000 or 1200 mg daily. All subjects received 48 weeks of therapy except for nongenotype 1 subjects in the combination treatment group who received only 24 weeks of therapy. The results show that at baseline, age, gender, risk factors, race, RNA titres, and liver histology were not different between the two groups. The proportion of subjects with genotype 1 infection was 50% (10/20) and 55% (11/20) for the monotherapy and combination therapy groups, respectively. Fifty (10/20) and sixty-five (13/20) per cent of subjects in the monotherapy and combination therapy groups exhibited a 2-log or greater decrease in viral titre at week 12 (P = NS). Using intent-to-treat analysis, 20% and 40% of enrolled subjects exhibited a sustained viral response in the monotherapy and combination therapy groups, respectively (P = NS). The proportion of subjects requiring dose reduction was 55% (11/20) and 65% (13/20), respectively. Study discontinuations for any reason were 25% (5/20) and 35% (7/20) for the monotherapy and combination groups, respectively. Discontinuations due to adverse events related to study drug were 20% (4/20) and 25% (5/20), respectively. A total of four serious adverse events occurred, two in each treatment group, only one of which was determined to be study-drug related. It is concluded that the safety and tolerability profiles of the two treatments were similar suggesting that daily dosing of CIFN may be difficult to tolerate resulting in discontinuation of therapy in a significant proportion of patients. The combination regimen resulted in a trend towards a higher viral response rate than monotherapy treatment. These data suggest that CIFN may be safely combined with ribavirin and may enhance the sustained response rate but is not well tolerated in US patients when given in a daily dosing regimen.

T(1rho) relaxation can assess longitudinal proteoglycan loss from articular cartilage in vitro

Objective To assess the correlation between changes in spin-lattice relaxation in the rotating frame (T(1rho)) and proteoglycan (PG) loss from bovine articular cartilage and to demonstrate the feasibility of performing T(1rho) MR imaging on a 1.5T clinical scanner. Design MR relaxation times (T(1rho), T(2) and T(1)) were measured from excised cartilage plugs (N=3) before and after two sequential digestions with trypsin on a 2T whole-body magnet. Proteoglycan and collagen loss induced by the trypsin digestion was measured using standard biochemical techniques. The correlation between changes in relaxation times and PG loss were tested with regression analysis. T(1rho) MRI was also performed on a clinical 1.5T MRI system to determine whether the spatial distribution of PG loss could be detected. The MRI results were compared with histology sections of native and PG-depleted tissue. Results Increase in T(1rho) relaxation times correlated with PG loss (R(2)=0.81). T(1rho) measurements alone were indicative of PG loss (R(2)=0.8), the addition of T1 and T2 data into the statistical model did not improve the correlation substantially (R(2)=0.83). T(1rho)-weighted imaging demonstrated a hyperintense lamina at the articular surface of the digested tissue, which was subjected to trypsin digestion that correlated with a superficial zone of PG loss observed on histological sections. Conclusion The results of this study demonstrate that T(1rho) relaxation changes are correlated with PG loss in vitro. Furthermore, T(1rho) measurements alone can be used to indicate PG loss data. T(1rho) MRI may thus be developed into a useful adjunct to existing techniques for the evaluation of cartilage disease.