Chitosan nanoparticles: a new vehicle for the improvement of the delivery of drugs to the ocular surface. Application to cyclosporin A

Present limitations in the management of extraocular diseases include the inability to provide long-term extraocular drug delivery without compromising intraocular structures and/or systemic drug exposure. In the present study, the potential of chitosan (CS) nanoparticles as a new vehicle for the improvement of the delivery of drugs to the ocular mucosa was investigated. Cyclosporin A (CyA) was chosen as a model compound because of its potential usefulness for the treatment of these local diseases. An ionic gelation technique was conveniently modified in order to produce CyA-loaded CS nanoparticles. These nanoparticles had a mean size of 293 nm, a zeta potential of +37 mV and high CyA association efficiency and loading (73 and 9%, respectively). In vitro release studies, performed under sink conditions, revealed a fast release during the first hour followed by a more gradual drug release during a 24-h period. In vivo experiments showed that, following topical instillation of CyA-loaded CS nanoparticles to rabbits, it was possible to achieve therapeutic concentrations in external ocular tissues (i.e., cornea and conjunctiva) during at least 48 h while maintaining negligible or undetectable CyA levels in inner ocular structures (i.e., iris/ciliary body and aqueous humour), blood and plasma. These levels were significantly higher than those obtained following instillation of a CS solution containing CyA and an aqueous CyA suspension. From these results, we can conclude that CS nanoparticles may represent an interesting vehicle in order to enhance the therapeutic index of clinically challenging drugs with potential application at extraocular level.

Design of biodegradable particles for protein delivery

Major research issues in protein delivery include the stabilization of proteins in delivery devices and the design of appropriate protein carriers in order to overcome mucosal barriers. We have attempted to combine both issues through the conception of new biodegradable polymer nanoparticles: (i) poly(ethylene glycol) (PEG)-coated poly(lactic acid) (PLA) nanoparticles, chitosan (CS)-coated poly(lactic acid-glycolic acid (PLGA) nanoparticles and chitosan (CS) nanoparticles. These nanoparticles have been tested for their ability to load proteins, to deliver them in an active form, and to transport them across the nasal and intestinal mucosae. Additionally, the stability of some of these nanoparticles in simulated physiological fluids has been studied. Results showed that the PEG coating improves the stability of PLA nanoparticles in the gastrointestinal fluids and helps the transport of the encapsulated protein, tetanus toxoid, across the intestinal and nasal mucosae. Furthermore, intranasal administration of these nanoparticles provided high and long-lasting immune responses. On the other hand, the coating of PLGA nanoparticles with the mucoadhesive polymer CS improved the stability of the particles in the presence of lysozyme and enhanced the nasal transport of the encapsulated tetanus toxoid. Finally, nanoparticles made solely of CS were also stable upon incubation with lysozyme. Moreover, these particles were very efficient in improving the nasal absorption of insulin as well as the local and systemic immune responses to tetanus toxoid, following intranasal administration. In summary, these results show that a rational modification in the composition and structure of the nanoparticles, using safe materials, increases the prospects of their usefulness for mucosal protein delivery and transport.

Oncogenic potential of EAG K(+) channels

We have investigated the possible implication of the cell cycle-regulated K(+) channel ether à go-go (EAG) in cell proliferation and transformation. We show that transfection of EAG into mammalian cells confers a transformed phenotype. In addition, human EAG mRNA is detected in several somatic cancer cell lines, despite being preferentially expressed in brain among normal tissues. Inhibition of EAG expression in several of these cancer cell lines causes a significant reduction of cell proliferation. Moreover, the expression of EAG favours tumour progression when transfected cells are injected into immune-depressed mice. These data provide evidence for the oncogenic potential of EAG.

Advantages of real-time PCR assay for diagnosis and monitoring of canine leishmaniosis

The aim of the present study is to highlight the advantages of real-time quantitative PCR intended to aid in the diagnosis and monitoring of canine leishmaniosis. Diagnosis of canine leishmaniosis is extremely challenging, especially in endemic areas, due to the diverse and non-specific clinical manifestations, and due to the high seroprevalence rate in sub-clinical dogs. Veterinarian clinicians are usually confronted with cases that are compatible with the disease, and with several diagnostic tests, sometimes with contradictory results. We have developed a new TaqMan assay, targeting the kinetoplast, applied to 44 samples of bone marrow aspirate or peripheral blood. The dynamic range of detection of Leishmania DNA was established in 7 logs and the limit of detection is 0.001 parasites in the PCR reaction. At the time of diagnosis parasitemia ranges from less than 1 to 10(7)parasites/ml. The ability to quantify the parasite burden allowed: (i) to elucidate the status of positive dogs by conventional PCR, although larger studies are necessary to clarify the dividing line between infection and disease, (ii) to estimate the kinetics of the parasite load and the different response to the treatment in a follow-up and (iii) to validate blood as less invasive sample for qPCR. The continuous data provided by real-time qPCR could solve the dilemma for the clinician managing cases of canine leishmaniosis by differentiating between Leishmania-infected dogs or dogs with active disease of leishmaniosis.

Stealth PLA-PEG nanoparticles as protein carriers for nasal administration

PURPOSE

The aim of the study was to encapsulate a model protein antigen, tetanus toxoid (TT), within hydrophobic (PLA) and surface hydrophilic (PLA-PEG) nanoparticles and to evaluate the potential of these colloidal carriers for the transport of proteins through the nasal mucosa.

METHODS

TT-loaded nanoparticles, prepared by a modified water-in-oil-in-water solvent evaporation technique, were characterized in their size, zeta potential and hydrophobicity. Nanoparticles were also assayed in vitro for their ability to deliver active antigen for extended periods of time. Finally, 125I-TT-loaded nanoparticles were administered intranasally to rats and the amount of radioactivity recovered in the blood compartment, lymph nodes and other relevant tissues was monitored for up to 48 h.

RESULTS

PLA and PLA-PEG nanoparticles had a similar particle size (137-156 nm) and negative surface charge, but differed in their surface hydrophobicity: PLA were more hydrophobic than PLA-PEG nanoparticles. PLA-PEG nanoparticles, especially those containing gelatine as an stabilizer, provided extended delivery of the active protein. The transport of the radiolabeled protein through the rat nasal mucosa was highly affected by the surface properties of the nanoparticles: PLA-PEG nanoparticles led to a much greater penetration of TT into the blood circulation and the lymph nodes than PLA nanoparticles. Furthermore, after administration of 125I-TT-loaded PLA-PEG nanoparticles, it was found that a high amount of radioactivity persisted in the blood compartment for at least 48 h.

CONCLUSIONS

A novel nanoparticulate system has been developed with excellent characteristics for the transport of proteins through the nasal mucosa.

Reactive oxygen species (ROS) mediates the mitochondrial-dependent apoptosis induced by transforming growth factor (beta) in fetal hepatocytes

Treatment of fetal rat hepatocytes with transforming growth factor beta (TGF-beta) is followed by apoptotic cell death. Analysis of radical oxygen species (ROS) content and mitochondrial transmembrane potential (Deltapsim), using specific fluorescent probes in FACScan and confocal microscopy, showed that TGF-beta mediates ROS production that precedes the loss of Deltapsim, the release of cytochrome c, and the activation of caspase 3. TGF-beta induces a decrease in the protein and mRNA levels of bcl-xL, an antiapoptotic member of the Bcl-2 family. In contrast, there is no change in the expression and/or translocation of Bax, a proapoptotic member of the same family. EGF maintains Bcl-xL, preventing Deltapsim collapse and release of cytochrome c. The presence of radical scavengers blocks the decrease in bcl-xL levels, Deltapsim collapse, cytochrome c release, and activation of caspase 3; in contrast, the presence of glutathione synthesis inhibitors such as BSO accentuated the effect. The incubation of fetal hepatocytes in the presence of ter-butyl-hydroperoxide alone produces a decrease in bcl-xL. These results indicate that during the apoptosis mediated by TGF-beta in fetal hepatocytes, ROS may be responsible for the decrease in bcl-xL mRNA levels that precedes the loss of Deltapsim, the release of cytochrome c, and the activation of caspase 3, culminating in cell death.

A sustained activation of PI3K/NF-kappaB pathway is critical for the survival of chronic lymphocytic leukemia B cells

The progressive rise of mature CD5+ B lymphocytes, despite the low proportion of proliferating cells, has led to the notion that B cell chronic lymphocytic leukemia (B-CLL) is primarily related to defective apoptosis. The microenvironment likely plays a prominent role because the malignant cells progressively accumulate in vivo, whereas they rapidly undergo spontaneous apoptosis when cultured in vitro. To assess microenvironment-mediated survival signals, B-CLL cells were cultured with a murine fibroblast cell line, Ltk-, with and without an agonistic antibody to CD40. Spontaneous apoptosis was associated with the loss of Akt and NF-kappaB activities. Interactions with fibroblasts sustained a basal level of Akt and NF-kappaB activities, which was dependent on phosphatidylinositol-3 kinase (PI3K). Constitutive activity of the PI3K pathway in B-CLL cells when cultured with fibroblasts prevented the downregulation of the prosurvival Bcl-2 family protein Bcl-xL and the caspase inhibitor proteins FLIPL and XIAP, and consequently caspase-3 activation and apoptosis. CD40 crosslinking in B-CLL cells did not further prevent murine fibroblasts-mediated apoptosis but induced cell proliferation, which was associated with an increase of Akt and NF-kappaB activation compared with cells cultured with fibroblasts alone. The PI3K pathway seems to play a pivotal role in B-CLL cell survival and growth.

Apoptosis induced by transforming growth factor-beta in fetal hepatocyte primary cultures: involvement of reactive oxygen intermediates

Transforming growth factor-beta (TGF-beta), a growth regulator of fetal hepatocytes in primary culture, also regulates death of these cells. Dose-response analysis showed that the TGF-beta concentration needed to induce hepatocyte death (2.5 ng/ml) was 5 times that needed to inhibit growth in these cells (0.5 ng/ml). In response to TGF-beta, hepatocytes induced DNA fragmentation and the appearance of nuclei with a DNA content lower than 2C (diploid content), typical of a programmed cell death model. TGF-beta-induced apoptosis in fetal hepatocytes was preceded by an induction of reactive oxygen species production and a decrease in the glutathione intracellular content, indicating that this factor induces oxidative stress in fetal hepatocytes. Studies performed to analyze levels of c-fos mRNA, a gene whose expression is modulated by redox state, demonstrated that only high, apoptotic concentrations of TGF-beta (2.5 ng/ml) produced an increase in the mRNA levels of this gene, the level of induction being similar to that found when cells were incubated in the presence of tert-butyl hydroperoxide. Gel mobility shift assays showed that the c-fos-induced expression was coincident with an increase in AP-1 activity. Finally, cell death induced by TGF-beta in fetal hepatocytes was partially blocked by radical scavengers, which decreased the percentage of apoptotic cells, whereas these agents did not modify the growth-inhibitory effect elicited by TGF-beta in these cells. In summary, the results presented in this paper provide evidence for the involvement of an oxidative process in the apoptosis elicited by TGF-beta in fetal hepatocytes.

Differential regulation of chordin expression domains in mutant zebrafish

Patterning along the dorsal-ventral (D-V) axis of Xenopus and Drosophila embryos is believed to occur through a conserved molecular mechanism, with homologous proteins Chordin and Short gastrulation (Sog) antagonizing signaling by bone morphogenetic protein 4 (BMP-4) and Decapentaplegic (Dpp), respectively. We have isolated a zebrafish gene that is highly homologous to chordin and sog within cysteine-rich domains and exhibits conserved aspects of expression and function. As in Xenopus embryos, zebrafish chordin is expressed in the organizer region and transiently in axial mesoderm. Injection of zebrafish chordin mRNA to the ventral side of Xenopus embryos induced secondary axes. Ectopic overexpression in zebrafish resulted in an expansion of paraxial mesoderm and neurectoderm at the expense of more lateral and ventral derivatives, producing a range of defects similar to those of dorsalized zebrafish mutants (Mullins et al., 1996). In accordance with the proposed function of chordin in D-V patterning, dorsalized zebrafish mutants showed expanded domains of chordin expression by midgastrulation, while some ventralized mutants had reduced expression; however, in all mutants examined, early organizer expression was unaltered. In contrast to Xenopus, zebrafish chordin is also expressed in paraxial mesoderm and ectoderm and in localized regions of the developing brain, suggesting that there are additional roles for chordin in zebrafish embryonic development. Surprisingly, paraxial mesodermal expression of chordin appeared unaltered in spadetail mutants that later lack trunk muscle (Kimmel et al., 1989), while axial mesodermal expression was affected. This finding reveals an unexpected function for spadetail in midline mesoderm and in differential regulation of chordin expression during gastrulation.

Hepatic metastases from colorectal cancer: preoperative detection and assessment of resectability with helical CT

PURPOSE

To prospectively evaluate helical computed tomography (CT) in the preoperative detection of hepatic metastases and assessment of resectability with surgical, intraoperative ultrasonographic (US), and histopathologic correlation.

MATERIALS AND METHODS

Between October 1995 and December 1998, preoperative staging with helical CT (5-mm collimation; reconstruction interval, 5 mm) was performed in 157 patients with hepatic metastases. Iodinated contrast material was injected intravenously (160-170 mL; rate, 2.5-3.0 mL/sec); acquisition began at 60-70 seconds. Four radiologists prospectively assessed the metastatic involvement of the liver by indicating the number and location of the lesions; resection was indicated in 113 patients (119 instances). Helical CT findings were correlated with pathologic and surgical findings on a lesion-by-lesion basis.

RESULTS

Intraoperative US, palpation, and histopathologic examination revealed 290 liver metastases; helical CT correctly depicted 247. Helical CT results were the following: overall detection rate, 85.1% (95% CI: 80.8%, 89.3%); positive predictive value, 96.1% (95% CI: 92.9%, 98.1%); and false-positive rate, 3.9% (10 of 257 findings; 95% CI: 1.9%, 7.1%). False-positive findings were related to hemangioendothelioma, hemangioma, hepatic peliosis, biliary adenoma, centrilobar hemorrhage, biliary hamartoma, periportal fibrosis, and normal liver parenchyma. Curative resection was performed in 112 instances with a resectability rate of 94.1%. Four-year patient survival rate was 58.6%.

CONCLUSION

Helical CT is a noninvasive, reliable, and accurate technique for imaging the liver and should be considered as the standard preoperative work-up of hepatic metastases from colorectal cancer.

Fungal Planet description sheets: 400-468

Novel species of fungi described in the present study include the following from Australia: Vermiculariopsiella eucalypti, Mulderomyces natalis (incl. Mulderomyces gen. nov.), Fusicladium paraamoenum, Neotrimmatostroma paraexcentricum, and Pseudophloeospora eucalyptorum on leaves of Eucalyptus spp., Anungitea grevilleae (on leaves of Grevillea sp.), Pyrenochaeta acaciae (on leaves of Acacia sp.), and Brunneocarpos banksiae (incl. Brunneocarpos gen. nov.) on cones of Banksia attenuata. Novel foliicolous taxa from South Africa include Neosulcatispora strelitziae (on Strelitzia nicolai), Colletotrichum ledebouriae (on Ledebouria floridunda), Cylindrosympodioides brabejum (incl. Cylindrosympodioides gen. nov.) on Brabejum stellatifolium, Sclerostagonospora ericae (on Erica sp.), Setophoma cyperi (on Cyperus sphaerocephala), and Phaeosphaeria breonadiae (on Breonadia microcephala). Novelties described from Robben Island (South Africa) include Wojnowiciella cissampeli and Diaporthe cissampeli (both on Cissampelos capensis), Phaeotheca salicorniae (on Salicornia meyeriana), Paracylindrocarpon aloicola (incl. Paracylindrocarpon gen. nov.) on Aloe sp., and Libertasomyces myopori (incl. Libertasomyces gen. nov.) on Myoporum serratum. Several novelties are recorded from La Réunion (France), namely Phaeosphaeriopsis agapanthi (on Agapanthus sp.), Roussoella solani (on Solanum mauritianum), Vermiculariopsiella acaciae (on Acacia heterophylla), Dothiorella acacicola (on Acacia mearnsii), Chalara clidemiae (on Clidemia hirta), Cytospora tibouchinae (on Tibouchina semidecandra), Diaporthe ocoteae (on Ocotea obtusata), Castanediella eucalypticola, Phaeophleospora eucalypticola and Fusicladium eucalypticola (on Eucalyptus robusta), Lareunionomyces syzygii (incl. Lareunionomyces gen. nov.) and Parawiesneriomyces syzygii (incl. Parawiesneriomyces gen. nov.) on leaves of Syzygium jambos. Novel taxa from the USA include Meristemomyces arctostaphylos (on Arctostaphylos patula), Ochroconis dracaenae (on Dracaena reflexa), Rasamsonia columbiensis (air of a hotel conference room), Paecilomyces tabacinus (on Nicotiana tabacum), Toxicocladosporium hominis (from human broncoalveolar lavage fluid), Nothophoma macrospora (from respiratory secretion of a patient with pneumonia), and Penidiellopsis radicularis (incl. Penidiellopsis gen. nov.) from a human nail. Novel taxa described from Malaysia include Prosopidicola albizziae (on Albizzia falcataria), Proxipyricularia asari (on Asarum sp.), Diaporthe passifloricola (on Passiflora foetida), Paramycoleptodiscus albizziae (incl. Paramycoleptodiscus gen. nov.) on Albizzia falcataria, and Malaysiasca phaii (incl. Malaysiasca gen. nov.) on Phaius reflexipetalus. Two species are newly described from human patients in the Czech Republic, namely Microascus longicollis (from toenails of patient with suspected onychomycosis), and Chrysosporium echinulatum (from sole skin of patient). Furthermore, Alternaria quercicola is described on leaves of Quercus brantii (Iran), Stemphylium beticola on leaves of Beta vulgaris (The Netherlands), Scleroderma capeverdeanum on soil (Cape Verde Islands), Scleroderma dunensis on soil, and Blastobotrys meliponae from bee honey (Brazil), Ganoderma mbrekobenum on angiosperms (Ghana), Geoglossum raitviirii and Entoloma kruticianum on soil (Russia), Priceomyces vitoshaensis on Pterostichus melas (Carabidae) (Bulgaria) is the only one for which the family is listed, Ganoderma ecuadoriense on decaying wood (Ecuador), Thyrostroma cornicola on Cornus officinalis (Korea), Cercophora vinosa on decorticated branch of Salix sp. (France), Coprinus pinetorum, Coprinus littoralis and Xerocomellus poederi on soil (Spain). Two new genera from Colombia include Helminthosporiella and Uwemyces on leaves of Elaeis oleifera. Two species are described from India, namely Russula intervenosa (ectomycorrhizal with Shorea robusta), and Crinipellis odorata (on bark of Mytragyna parviflora). Novelties from Thailand include Cyphellophora gamsii (on leaf litter), Pisolithus aureosericeus and Corynascus citrinus (on soil). Two species are newly described from Citrus in Italy, namely Dendryphiella paravinosa on Citrus sinensis, and Ramularia citricola on Citrus floridana. Morphological and culture characteristics along with ITS nrDNA barcodes are provided for all taxa.

A type I interferon signature in monocytes is associated with poor response to interferon-beta in multiple sclerosis

The effect of interferon-beta in multiple sclerosis is modest and many patients do not respond to treatment. To date, no single biomarker reliably correlates with responsiveness to interferon-beta in multiple sclerosis. In the present study, genome-wide expression profiling was performed in peripheral blood mononuclear cells from 47 multiple sclerosis patients treated with interferon-beta for a minimum of 2 years and classified as responders and non-responders based on clinical criteria. A validation cohort of 30 multiple sclerosis patients was included in the study to replicate gene-expression findings. Before treatment, interferon-beta responders and non-responders were characterized by differential expression of type I interferon-induced genes with overexpression of the type interferon-induced genes in non-responders. Upon treatment the expression of these genes remained unaltered in non-responders, but was strongly upregulated in responders. Functional experiments showed a selective increase in phosphorylated STAT1 levels and interferon receptor 1 expression in monocytes of non-responders at baseline. When dissecting this type I interferon signature further, interferon-beta non-responders were characterized by increased monocyte type I interferon secretion upon innate immune stimuli via toll-like receptor 4, by increased endogenous production of type I interferon, and by an elevated activation status of myeloid dendritic cells. These findings indicate that perturbations of the type I interferon signalling pathway in monocytes are related to lack of response to interferon-beta, and type I interferon-regulated genes may be used as response markers in interferon-beta treatment.

Lack of efficacy of atenolol for the prevention of neurally mediated syncope in a highly symptomatic population: a prospective, double-blind, randomized and placebo-controlled study

OBJECTIVES

This study was designed to evaluate the efficacy of atenolol for the long-term management of patients with vasovagal syncope. The primary hypothesis was that atenolol is not superior to placebo for the treatment of vasovagal syncope.

BACKGROUND

There is no definitive well-controlled analysis of the efficacy of beta-adrenergic blocking agents in patients with recurrent vasovagal syncope.

METHODS

This is a prospective, randomized, double-blind, placebo-controlled study. Fifty patients with recurrent vasovagal syncope were included (at least two episodes in the last year). A baseline tilt test was performed. Twenty patients (40%) had a positive tilt test. Intravenous atenolol prevented a second positive tilt in five patients. The patients were randomized to receive either atenolol or a placebo (26 patients atenolol 50 mg/day, 24 patients placebo). The follow-up procedure lasted one year. The primary end point of the study was the time to first recurrence of syncope.

RESULTS

In the intention-to-treat analysis, the group treated with atenolol had a similar number of patients with recurrent syncopal episodes as the placebo group. The Kaplan-Meier actuarial estimates of time to first syncopal recurrence showed that the probability of remaining free of syncope drops similarly in both groups and that there was no statistical difference between both curves (patients treated with atenolol vs. the placebo) with a log-rank test p value of 0.4517.

CONCLUSIONS

The recurrence of neurocardiogenic syncope in highly symptomatic patients treated with atenolol is similar to that of patients treated with placebo.

Safety and patient-reported outcomes of atezolizumab, carboplatin, and etoposide in extensive-stage small-cell lung cancer (IMpower133): a randomized phase I/III trial

BACKGROUND

The addition of atezolizumab to carboplatin and etoposide (CP/ET) significantly improved progression-free and overall survival for patients with extensive-stage small-cell lung cancer (ES-SCLC) in the IMpower133 study (NCT02763579). We have evaluated adverse events (AEs) and patient-reported outcomes in IMpower133 to assess the benefit-risk profile of this regimen.

PATIENTS AND METHODS

Patients received four 21-day cycles of CP/ET plus intravenous atezolizumab 1200 mg or placebo (induction phase), followed by atezolizumab or placebo (maintenance phase) until progression or loss of benefit. AEs were assessed and patient-reported outcomes were evaluated every 3 weeks during treatment using the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire - Core 30 (QLQ-C30) and QLQ-LC13.

RESULTS

Overall, 394 patients were assessable for safety in the induction phase and 318 in the maintenance phase. The frequency of AEs, grade 3-4 AEs, and serious AEs was similar between arms in both phases. Immune-related AEs were more frequent in the atezolizumab arm during both induction (28% versus 17%; leading to atezolizumab/placebo interruption 9% versus 5%, leading to withdrawal 4% versus 0%) and maintenance (26% versus 15%; leading to atezolizumab/placebo interruption, 3% versus 2%, leading to withdrawal 1% versus 1%), most commonly rash (induction 11% versus 9%, maintenance 14% versus 4%), and hypothyroidism (induction 4.0% versus 0%, maintenance 10% versus 1%). Changes in patient-reported treatment-related symptoms commonly associated with quality of life impairment were generally similar during induction and most of the maintenance phase. Patient-reported function and health-related quality of life (HRQoL) improved in both arms after initiating treatment, with more pronounced and persistent HRQoL improvements in the atezolizumab arm.

CONCLUSIONS

In patients with ES-SCLC, atezolizumab plus CP/ET has a comparable safety profile to placebo plus CP/ET, and the addition of atezolizumab did not adversely impact patient-reported HRQoL. These data demonstrate the positive benefit-risk profile of first-line atezolizumab plus CP/ET in ES-SCLC and further support this regimen as a new standard of care in this setting.

CLINICAL TRIALS NUMBER

NCT02763579.

PLA-PEG particles as nasal protein carriers: the influence of the particle size

Previous studies have shown that PLA-PEG nanoparticles (NP) are able to enhance the transport of the encapsulated model protein, tetanus toxoid (TT), across the rat nasal mucosa. The aim of this work was to study if the size of PLA-PEG particles affects the nasal transport of the encapsulated protein and, also, the potential contribution of blank nanoparticles to the transport of the free protein. To achieve this purpose, 125I-TT was encapsulated into PLA-PEG particles of different sizes (200 nm, 1.5, 5 and 10 microm) prepared by the water-in-oil-in-water solvent evaporation technique. Firstly, in order to investigate the carrier role of the particles, two series of either conscious or anaesthetized rats were nasally treated with 125I-TT-loaded NP, free 125I-TT, and a physical mixture of blank NP and free 125I-TT. Secondly, the influence of the particle size on the nasal transport of TT encapsulated into PLA-PEG particles was evaluated in conscious rats. The amount of radioactivity recovered in the blood compartment, lymph nodes and other relevant tissues was monitored for up to 24h. Finally, the nasal bioavailability of 125I-TT-loaded PLA-PEG NP was calculated. The results indicated that the use of anaesthesia enhances the transport of 125I-TT and that the physical presence of PLA-PEG NP does not affect the transport of the toxoid. In contrast, when TT was encapsulated into the particles its transport across the nasal mucosa of conscious rats was significantly enhanced. Furthermore, the efficacy of this transport was related to the particle size, reaching the most important transport for the smallest particle size. The intensity of this transport was also illustrated by the high nasal bioavailability of TT encapsulated into nanoparticles (200 nm) (F = 70-80%). These results led us to conclude that PLA-PEG NP can be accepted as nasal protein carriers for nasal administration.

Inhibitory neurons in the human epileptogenic temporal neocortex. An immunocytochemical study

Immunocytochemical methods were used to study alterations in inhibitory neuronal circuits in human neocortex resected during surgical treatment of intractable temporal epilepsy associated or not with brain tumours. The epileptogenic cortex was characterized and divided into spiking or non-spiking zones by intraoperative electrocorticography (ECOG). The resected cortex was cut into blocks, sectioned and stained immunocytochemically for visualization of glutamic acid decarboxylase (GAD), the calcium-binding protein, parvalbumin (PV) and glial fibrillary acidic protein (GFAP). A variety of alterations in cortical neuronal circuits as revealed by immunocytochemical and histological methods were found. Similar alterations in inhibitory neuronal circuits appear to occur independently of the primary epileptogenic site and pathology associated with epilepsy, which suggests that there is possibly a common basic underlying mechanism that leads to seizure activity. These changes were apparently unrelated to ECOG findings at surgery, which bring into question the value of the use of interictal epileptic discharges recorded by ECOG to guide cortical resections. The most conspicuous and common change was the loss of chandelier cells. The finding that these cells are among the most vulnerable types of GABAergic interneurons in the epileptogenic temporal cortex indicates that they might be of great functional importance, since the axon terminals of chandelier cells are likely to exert powerful regulation of impulse generation in cortical pyramidal cells. Therefore, these cells might represent a key component in the aetiology of human epilepsy.

Cancer antigen 125 associated with multiple benign and malignant pathologies

BACKGROUND

Cancer antigen (CA) 125 tumor-associated antigen is a high molecular glycoprotein used for follow-up of epithelial ovarian cancer. The test is often requested as a differential diagnosis in patients with pleural or peritoneal fluid. This study analyzes the prevalence of CA-125 increases in a population of patients attending a general hospital and discusses the possible clinical implications of increased levels.

METHODS

On 4 different days, 380 CA-125 assays were performed in randomly selected patients attending our hospital. Serum CA-125 was measured with a commercial enzyme immunoassay, and clinical records were reviewed for assessment of clinical parameters.

RESULTS

Sixty-one patients (16%) had increased CA-125. The pathologies of these patients were heart failure in 9 (14.7%), lung disease 11 (18%), hepatic cirrhosis in 7 (11.4%), malignant tumors in 9 (14.7%), intra-abdominal nonhepatic disease in 6 (10%), previous surgery in 17 (27.8%), and miscellaneous in 2 (3%). Effusions were seen in 34 patients (55.7%).

CONCLUSIONS

Our data confirm the variety of benign and malignant pathologies coursing with increased CA-125. Cardiovascular and chronic liver disease were the most frequent diagnoses in patients with increased CA-125; this supports the opinion that CA-125 lacks utility as a marker for malignancy. CA-125 could have a role in the follow-up of cardiovascular, hepatic, and tumoral diseases with serosal involvement.

A QTL on pig chromosome 4 affects fatty acid metabolism: evidence from an Iberian by Landrace intercross

Three Iberian boars were bred to 31 Landrace sows to produce 79 F1 pigs. Six F1 boars were mated to 73 F1 sows. The F2 progeny from 33 full-sib families (250 individuals) were genotyped for seven microsatellites spanning the length of chromosome 4. Least squares procedures for interval mapping were used to detect quantitative trait loci (QTL). A permutation test was used to establish nominal significance levels associated with QTL effects, and resulting probability levels were corrected to a genomewide basis. Observed QTL effects were (genomewide significance, position of maximum significance in centimorgans): percentage of linoleic acid in subcutaneous adipose tissue (< 0.01, 81); backfat thickness (< 0.01, 83); backfat weight (< 0.01, 80); longissimus muscle area (0.02, 83); live weight (0.19, 88); and percentage of oleic acid in subcutaneous adipose tissue (0.25, 81). Gene action was primarily additive. The Iberian genotypes were fatter, slower growing, and had lower linoleic and higher oleic acid contents than Landrace genotypes. The interval from 80 to 83 cM contains the FAT1 and A-FABP loci that have been shown previously to affect fat deposition in pigs. This is the first report of a QTL affecting fatty acid composition of subcutaneous adipose tissue in pigs and provides a guide for the metabolic pathways affected by candidate genes described in this region of chromosome 4.

Principal mutation hotspot for central core disease and related myopathies in the C-terminal transmembrane region of the RYR1 gene

The congenital myopathies are a group of disorders characterised by the predominance of specific histological features observed in biopsied muscle. Central core disease and nemaline myopathy are examples of congenital myopathies that have specific histological characteristics but significantly overlapping clinical pictures. Central core disease is an autosomal dominant disorder with variable penetrance which has been linked principally to the gene for the skeletal muscle calcium release channel (RYR1). Two recent reports have identified the 3' transmembrane domain of this gene as a common site for mutations. Two other studies have reported single families that have features of both central core disease and nemaline myopathy (core/rod disease) caused by mutations in RYR1. Screening of the 3' region (exons 93-105) of the RYR1 gene for mutations in 27 apparently unrelated patients with either central core disease or core/rod disease by single strand conformation polymorphism analysis and DNA sequencing identified three described and nine novel mutations in 15 patients.

The value of capsule endoscopy in pediatric patients with a suspicion of Crohn's disease

BACKGROUND AND STUDY AIMS

The aim of this study was to assess the safety and usefulness of capsule endoscopy (CE) in pediatric patients with a suspicion of Crohn's disease.

PATIENTS AND METHODS

CE was used in 12 patients (four girls, eight boys; age 12-16; weight range 43-87 kg). The indication was a clinical suspicion of Crohn's disease not confirmed with traditional methods. Gastroscopy, colonoscopy, and small-bowel follow-through examinations were carried out in all of the patients, without any diagnostic findings. Ileoscopy was possible in 50 % of the patients, and the ileal mucosa and biopsies were normal in all cases.

RESULTS

The capsule was easily swallowed by all of the patients. They all excreted the capsule normally, and no complications were observed in any case. CE identified lesions suggestive of Crohn's disease in seven of the 12 (58.3 %), and the majority of the lesions were in the ileum.

CONCLUSIONS

CE is safe in pediatric patients over 12 years of age. The procedure appears to be a very useful diagnostic tool in children with Crohn's disease.

PEG-PLA nanoparticles as carriers for nasal vaccine delivery

This report presents an overview of the potential of nanoparticles as nasal carriers for drug/vaccine administration. In addition, this report shows, for the first time, the efficacy of polylactic acid nanoparticles coated with a hydrophilic polyethyleneglycol coating (PEG-PLA nanoparticles) as carriers for the nasal transport of bioactive compounds. For this purpose, tetanus toxoid (TT), a high molecular weight protein (Mw 150,000 Da), was chosen as a model antigen and encapsulated in the PEG-PLA nano- and microparticles (200 nm and 1.5 microm respectively). These nanosystems were first characterized for their stability in the presence of lysozyme and also for their size, electrical charge, loading efficiency, in vitro release of antigenically active toxoid and afterwards, these formulations were administered intranasally to mice and the systemic and mucosal anti-tetanus responses were evaluated for up to 24 weeks. Additionally, PEG-PLA particles labeled with rhodamine 6G were administered intranasally to rats in order to visualize their interaction with the nasal mucosae by fluorescence microscopy. Their behavior was compared with that of the well known PLA nanoparticles (200 nm). The results showed that PLA nanoparticles suffered an immediate aggregation upon incubation with lysozyme, whereas the PEG-coated nanoparticles remained totally stable. The antibody levels elicited following i.n. administration of PEG-coated nanoparticles were significantly higher than those corresponding to PLA nanoparticles. Furthermore, PEG-PLA nanoparticles generated an increasing and a long lasting response. The qualitative fluorescence microscopy studies revealed that PEG-PLA particles are able to cross the rat nasal epithelium. These studies indicate that the PEG coating around the particles has a role in stabilizing PLA particles in mucosal fluids and that it facilitates the transport of the nanoencapsulated antigen, hence eliciting a high and long lasting immune response.