Alginate/chitosan nanoparticles are effective for oral insulin delivery

PURPOSE

To evaluate the pharmacological activity of insulin-loaded alginate/chitosan nanoparticles following oral dosage in diabetic rats.

METHODS

Nanoparticles were prepared by ionotropic pre-gelation of an alginate core followed by chitosan polyelectrolyte complexation. In vivo activity was evaluated by measuring the decrease in blood glucose concentrations in streptozotocin induced, diabetic rats after oral administration and flourescein (FITC)-labelled insulin tracked by confocal microscopy.

RESULTS

Nanoparticles were negatively charged and had a mean size of 750 nm, suitable for uptake within the gastrointestinal tract due to their nanosize range and mucoadhesive properties. The insulin association efficiency was over 70% and insulin was released in a pH-dependent manner under simulated gastrointestinal conditions. Orally delivered nanoparticles lowered basal serum glucose levels by more than 40% with 50 and 100 IU/kg doses sustaining hypoglycemia for over 18 h. Pharmacological availability was 6.8 and 3.4% for the 50 and 100 IU/kg doses respectively, a significant increase over 1.6%, determined for oral insulin alone in solution and over other related studies at the same dose levels. Confocal microscopic examinations of FITC-labelled insulin nanoparticles showed clear adhesion to rat intestinal epithelium, and internalization of insulin within the intestinal mucosa.

CONCLUSION

The results indicate that the encapsulation of insulin into mucoadhesive nanoparticles was a key factor in the improvement of its oral absorption and oral bioactivity.

Endoscopic ultrasound-guided fine-needle aspiration and Trucut biopsy in thoracic lesions: when tissue is the issue

BACKGROUND

Endoscopic ultrasound-guided fine-needle aspiration (EUS FNA) has a high accuracy in the evaluation of mediastinal lesions. The use of a core biopsy needle for EUS guided biopsy (EUS TCB) may further improve the yield of EUS. The aims of this study are to evaluate the safety of EUS TCB in thoracic lesions and to compare the diagnostic accuracy of TCB with FNA and FNA + TCB.

METHODS

A single-center retrospective study. All patients underwent EUS-FNA and TCB. A cytopathologist was not present during the procedure. EUS FNA, TCB and FNA + TCB diagnostic accuracy were compared.

RESULTS

A total of 48 patients were included. The lesions sampled included 41 lymph nodes (six aorto-pulmonary window, 32 subcarinal, two right paratracheal, one paraesophageal ATS station 8), five lung masses, and two esophageal masses. Twenty-nine patients had malignant disease and 19 had benign disorders. The overall diagnostic accuracy of FNA, TCB and FNA + TCB was 79%, 79% and 98% respectively (p = 0.007). TCB changed the diagnosis in nine cases missed by FNA. EUS TCB was better than FNA for benign diseases (89% vs. 63%, p = 0.04). All eight patients with a prior failed biopsy had a correct diagnosis established by EUS. No patient required mediastinoscopy or thoracoscopy after EUS.

CONCLUSION

The combination of TCB and FNA is superior to FNA alone. EUS-guided TCB should be considered in patients with benign disorders of the mediastinum when other modalities fail to yield a diagnosis.

Analysis of the immune response to Neospora caninum in a model of intragastric infection in mice

To study experimental Neospora caninum infection initiated at the gastrointestinal tract, Toll-like Receptor 4- and functional IL-12Rbeta2 chain-deficient C57BL/10 ScCr mice were challenged intragastrically with 5 x 10(6) N. caninum tachyzoites. All parasite-inoculated mice eventually died with disseminated infection. In contrast, immunocompetent BALB/c mice challenged with 1 x 10(7) N. caninum tachyzoites by the intragastric (i.g.) or the intraperitoneal (i.p.) route remained alive for at least 6 months. Expansion of splenic B- and T-cells, the latter displaying both activated and regulatory phenotypes, and increased levels of IFN-gamma and IL-10 mRNA were detected in both groups of infected BALB/c mice compared with non-infected controls, whereas in the Peyer's patches only IFN-gamma mRNA levels were found to be increased. Parasite-specific IgG1, IgG2a and IgA antibody levels were elevated in the sera of all infected mice, whereas increased N. caninum-specific IgA levels were detected in intestinal lavage fluids of i.g. challenged mice only. These results show that N. caninum infection can be successfully established in mice by i.g. administration of tachyzoites. They also show that the immune response elicited in i.g. or i.p. infected BALB/c mice, although conferring some degree of protection, was not sufficient for complete parasite clearance.

Simultaneous Pancreas-Kidney Transplantation: Five-Year Results From a Single Center

We report the 5-year results of our simultaneous pancreas-kidney transplantation (SPKT) program, started on May 2, 2000. Forty-two SPKT were performed on 42 type I diabetic patients with chronic renal failure. The procedure was performed with enteric diversion and vascular anastomosis to the iliac vessels. Immunosuppressive protocol included antithymocyte globulin, tacrolimus, mycophenolate mofetil, and steroids. The 24 women and 18 men had a mean age of 33.5 +/- 6.3 years and mean 22.8 +/- 14.2 years time of diabetes evolution. Forty patients had been on dialysis for 34.3 +/- 24.1 months, and two were preemptive transplantations. Acute rejection episodes were treated in eight patients (19.1%): in three cases they affected both organs; in two only the kidney was affected; and the other three were pancreas graft rejections. The incidence of postoperative complications requiring re-operation was 42.9%, mostly pancreas graft related. Two patients died, one due to cardiovascular disease; the other was transplant related. Three kidney grafts were lost, and the causes were immunologic, thrombosis, and patient death. Pancreas graft loss occurred in seven patients: thrombosis (n = 3); infection (n = 3); immunologic (n = 1). The patients with surviving grafts were doing well, with normal kidney and pancreas function: serum creatinine = 0.89 +/- 0.15 mg/dL; fasting blood glucose = 79 +/- 16 mg/dL; HbA1c = 4.7 +/- 1.1%. The 1-year patient, kidney, and pancreas survival rates were 97.3%, 94.6%, and 83.8% and 5-year values, 91.7%, 89.2%, and 78.7%, respectively. In conclusion, these results are similar to the most recent UNOS/IPTR reports, leading us to consider our experience with SPKT very positive.

A phase II trial of capecitabine and docetaxel in patients with previously treated pancreatic cancer

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Background: There is no accepted standard treatment for patients with advanced pancreatic cancer who progress after gemcitabine-based therapy. Capecitabine and docetaxel have single-agent activity in pancreatic cancer and have documented synergy in both pre-clinical models and in the treatment of other solid tumors. Methods: A phase II trial with a 3-stage sequential design was planned to assess the efficacy (primary end-point: response rate) and toxicity of capecitabine 800 mg/m2 PO bid on days 1–14 in combination with docetaxel 30 mg/m2 IV on days 1 and 8 of each 21-day cycle in patients with advanced pancreatic cancer who failed first-line gemcitabine-based chemotherapy. If no responses are observed after 13 patients or less than 3 responses are seen after 26 patients, accrual will stop and the combination deemed ineffective. Results: Eight patients have been enrolled (5 women, 3 men). Median age was 67 years. ECOG PS was as follows: PS 1, three patients; PS 2, five patients. All patients had adequate organ function. A total of 26 cycles have been administered (median: 2 cycles, range 1 to 8). Four patients had stable disease (median duration 9 weeks, range 6 to 24), and 3 had progressed at the time of first evaluation (2 cycles). One patient has not yet completed 2 cycles and is therefore not assessable for radiologic response. Out of 7 patients with an elevated CA 19–9, four had a decrease of 50% or greater while on chemotherapy. Grade 1 or 2 toxicity was seen in 3 patients (diarrhea, 1 patient; fatigue, 2 patients). Grade 3 or 4 toxicity was as follows: fatigue, 2 patients; dehydration, 1 patient; neuropathy, 1 patient. There were no treatment related deaths. Enrollment continues. Efficacy data fulfilling the first stage sequential design should be available at the time of the meeting. Median survival for all patients is currently 13 weeks (range 7–23 weeks) Conclusions: Capecitabine in combination with docetaxel is a well-tolerated regimen in the treatment of patients with pancreatic cancer who have failed prior gemcitabine-based therapy. Four out of 8 patients have had stable disease. Four of 7 patients have had a decrease of 50% or greater in CA 19.9 levels. Enrollment continues. Median survival of 13 weeks underscores the poor prognosis of this patient population.

[Table: see text]

Possible applications for municipal solid waste fly ash

The present study focuses on existing practices related to the reuse of Municipal Solid Waste (MSW) fly ash and identifies new potential uses. Nine possible applications were identified and grouped into four main categories: construction materials (cement, concrete, ceramics, glass and glass-ceramics); geotechnical applications (road pavement, embankments); "agriculture" (soil amendment); and, miscellaneous (sorbent, sludge conditioning). Each application is analysed in detail, including final-product technical characteristics, with a special emphasis on environmental impacts. A comparative analysis of the different options is performed, stressing the advantages but also the weaknesses of each option. This information is systemized in order to provide a framework for the selection of best technology and final products. The results presented here show new possibilities for this waste reuse in a short-term, in a wide range of fields, resulting in great advantages in waste minimization as well as resources conservation.

Direct determination of chlorophenols in landfill leachates by solid-phase micro-extraction-gas chromatography-mass spectrometry

Landfill leachates represent a serious environmental concern with regard to trace priority pollutants introduced into the aquatic environment. From the analytical point of view, they constitute complex matrices because of their high organic matter content and competition with the trace analytes in the extraction procedure. Although the use of SPME to extract chlorophenols in leachates has already been described in several publications, the limited number of chlorophenols restricts this analysis field of application. This paper presents a new analytical methodology to determine 13 chlorophenols and phenol by SPME-GC-MS in landfill leachates. The overall analysis was performed in 90 min and the detection limits range from 0.005 microg/l (pentachlorophenol) to 2.5 microg/l (phenol). Reproducibility, expressed by the coefficient of variation of repeated extractions at different concentration levels of the analytes, was on average inferior to 10%. Recovery, evaluated by standard addition to leachates, was 86.2% on average. Pentachlorophenol, 2,3,4,5-tetrachlorophenol and 2,3,4,6-tetrachlorophenol were the sole analytes detected at nanogram level in the landfill leachates analysed.

[Uncomplicated acute myocardial infarction -- when should the patient be discharged?]

INTRODUCTION AND OBJECTIVES

Hospital discharge on day 10 after acute myocardial infarction (AMI) is still frequent in our hospital. The present study aims at evaluating the occurrence of cardiac events on day 5, 7 and 10, in patients with AMI who had an uncomplicated course for 72 hours after thrombolysis, as well as a cost-effectiveness analysis on an earlier discharge.

METHODS

We retrospectively studied consecutive patients admitted with AMI for a period of 5 years, submitted to thrombolysis who suffered no events (recurrent ischemia, reinfarction, coronary revascularization, heart failure, arrhythmias implicating electric cardioversion or dysfibrilation, pacemaker or death) within the first 72 hours (n = 128; 101 males and 27 females, mean age 64.1 +/- 12.8). Patients were divided into two groups, with no events occurring by discharge (group I, n = 119) or with events between 72 hours and discharge (group II, n = 9). The latter were subdivided according to whether events occurred between 72 hours and day 5, between days 6 and 7 or between 8 and 10.

RESULTS

Group I and II were not significantly different regarding vascular risk factors, prior coronary disease and infarction location. Group I was mainly constituted of males, younger than those in group II and with preserved systolic LV function. Between 72 hours and discharge, there were no events in 93% of the patients (119) and events occurred in 7% (9 patients). Two cases of cardiac events occurred until day 5 (1.6%) one angina and one death, two patients with complications between days 6 and 7 (1.6%), both heart failure, and 5 patients suffered events after day 7 (4%), 3 angina and 2 deaths. Dead patients (3 cases--2.3%) were older, had prior AMI, mostly with unpreserved systolic LV function and prior ischemic heart disease. All of them had sudden death. The most frequent non-fatal complications were recurrent ischemia and heart failure.

CONCLUSIONS AND IMPLICATIONS

In patients with AMI who had an uncomplicated course for 72 hours after thrombolysis, the risk of cardiac events by the 10th day is low. It occurs randomly in time. In this group of patients it seems of no effectiveness to lengthen hospitalization. An earlier discharge may be advantageous since it does not significantly increase the risk that a longer hospitalization could prevent.

Expression of results with uncertainty for the determination of pesticides in melon--experience in a proficiency test

The expression of results with an uncertainty through the "bottom-up" approach, involving the estimation and combination of all the sources of uncertainty, represents a challenge when the analytical method includes mass transfer steps (MTS). These steps (e.g. extraction, evaporation, digestion, etc.) with inherently different from 100% recoveries lack models capable of describing their precision and efficiency. Recently, a new methodology was published aimed at the estimation of the performance of these critical steps. Comparison of the experimental dispersion from the replicated analysis of spiked samples with the combination of the uncertainty associated with gravimetric, volumetric and instrumental quantification steps (described by well established models) allows the estimation of the MTS uncertainty. Evaluation of the behaviour of the MTS within the analytical range supports the use of developed estimations over a wide concentration range. This methodology was applied, with success, to the determination of pesticide residues in melon in one particular proficiency test organised by the Food Analysis Performance Assessment Scheme (FAPAS) between November 2000 and February 2001.

EUS-guided fine-needle aspiration combined with flow cytometry and immunocytochemistry in the diagnosis of lymphoma

BACKGROUND

Limited information is available regarding the use of EUS-guided fine-needle aspiration (EUS-FNA) in the diagnosis of lymphoproliferative disorders. The aim of this study was to evaluate the yield of this technique in the primary diagnosis of lymphoma.

METHODS

The records were reviewed of 38 consecutive patients with GI lesions and/or enlarged lymph nodes identified on imaging studies that raised a suspicion of lymphoma who underwent EUS-FNA of lymph nodes or the gut wall. Final diagnosis was based on clinical follow-up, imaging studies, or surgical findings.

RESULTS

Twenty-three patients with lymphoma and 15 patients with benign disease or reactive lymphadenopathy were identified. The overall sensitivity, specificity, and accuracy of EUS-FNA cytology with flow cytometry/immunocytochemistry (FC/IC) for the diagnosis of lymphoma were, respectively, 74%, 93%, and 81%. When comparing patients who had EUS-FNA with FC/IC versus those who had EUS-FNA without FC/IC, sensitivity was 86% versus 44% (p = 0.04), specificity was 100% versus 90% (not significant), and accuracy was 89% versus 68% (not significant).

CONCLUSION

EUS-FNA can provide cytology specimens diagnostic for lymphoma. Selective use of FC/IC in patients with suspected lymphoma improves the yield of EUS-FNA and may guide diagnostic evaluation and treatment decisions.

Localized hepatocellular carcinoma: therapeutic options

Hepatocellular carcinoma (HCC) is among the most common malignancies worldwide. Recent surveillance programs have allowed early detection and diagnosis, but overall survival of patients with HCC remains poor. This article provides a definition for localized HCC and summarizes the array of treatments that have emerged and the salient literature and findings for each. Among the treatments reviewed here are surgical resection, orthotopic liver transplantation, and local ablative therapies such as cryosurgery, percutaneous ethanol injection therapy, and transarterial chemoembolization.

Characterization of a Casuarina glauca nodule-specific subtilisin-like protease gene, a homolog of Alnus glutinosa ag12

In search of plant genes expressed during early interactions between Casuarina glauca and Frankia, we have isolated and characterized a C. glauca gene that has strong homology to subtilisin-like protease gene families of several plants including the actinorhizal nodulin gene ag12 of another actinorhizal plant, Alnus glutinosa. Based on the expression pattern of cg12 in the course of nodule development, it represents an early actinorhizal nodulin gene. Our results suggest that subtilisin-like proteases may be a common element in the process of infection of plant cells by Frankia in both Betulaceae (Alnus glutinosa) and Casuarinaceae (Casuarina glauca) symbioses.

A new cyclohexadecane derivative from Trixis vauthieri DC (Asteraceae)

The dichloromethane-methanol extract from the fresh leaves of Trixis vauthieri DC (Asteraceae) afforded trixol, a new cyclohexadecane derivative. The structural elucidation of this new compound, with a novel skeleton, was based on NMR studies of the natural product nd its derivatives.

The transforming growth factor beta(1)-inducible transcription factor TIEG1, mediates apoptosis through oxidative stress

Transforming growth factor beta(1) (TGF-beta(1))-inducible transcription factors have recently elicited interest because of their critical role in the regulation of cell proliferation, differentiation, and apoptosis. We have previously reported that the TGF-beta(1)-inducible transcription factor, TIEG1, induces apoptosis in a pancreas-derived cell line. However, the mechanisms underlying the apoptotic effects of this transcription factor remain to be defined. In this study, using the TGF-beta(1)-sensitive Hep 3B cell line, we have defined the mechanistic sequence of events that characterize TIEG1-mediated apoptosis and compared these events with the changes observed during TGF-beta(1)-induced apoptosis. Both TGF-beta(1)- and TIEG1-induced cell death were accompanied by an increase in the generation of reactive oxygen species and a loss of the mitochondrial membrane potential preceding the morphological changes of apoptosis. In contrast, increases in caspase 3-like activity and glutathione (GSH) depletion occurred later in the apoptotic process, concurrent with the morphological features of apoptosis. The antioxidant, trolox, decreased the formation of reactive oxygen species and apoptosis. These results demonstrate that similar to TGF-beta(1), TIEG1 induces apoptosis by a mechanism involving the formation of reactive oxygen species.

Non-coronary sinus of Valsalva aneurysm diagnosed after a road traffic accident

A 38 year old man with a huge unruptured sinus of Valsalva aneurysm, complicated with severe valvar aortic regurgitation, is described. The aneurysm was detected by echocardiography in the asymptomatic patient who presented with an intense precordial diastolic rumble after a road traffic accident. The patient had successful surgery for the aneurysm and aortic valve replacement. Possible aetiologies for the aneurysm and a brief revision of clinical aspects and treatment are discussed.