4,611 research outputs found
Liposomes characterization for market approval as pharmaceutical products: Analytical methods, guidelines and standardized protocols
Liposomes are nano-sized lipid-based vesicles widely studied for their drug delivery capabilities. Compared to standard carries they exhibit better properties such as improved site-targeting and drug release, protection of drugs from degradation and clearance, and lower toxic side effects. At present, scientific literature is rich of studies regarding liposomes-based systems, while 14 types of liposomal products have been authorized to the market by EMA and FDA and many others have been approved by national agencies. Although the interest in nanodevices and nanomedicine has steadily increased in the last two decades the development of documentation regulating and standardizing all the phases of their development and quality control still suffers from major inadequacy due to the intrinsic complexity of nano-systems characterization. Many generic documents (Type 1) discussing guidelines for the study of nano-systems (lipidic and not) have been proposed while there is a lack of robust and standardized methods (Type 2 documents). As a result, a widespread of different techniques, approaches and methodologies are being used, generating results of variable quality and hard to compare with each other. Additionally, such documents are often subject to updates and rewriting further complicating the topic. Within this context the aim of this work is focused on bridging the gap in liposome characterization: the most recent standardized methodologies suitable for liposomes characterization are here reported (with the corresponding Type 2 documents) and revised in a short and pragmatical way focused on providing the reader with a practical background of the state of the art. In particular, this paper will put the accent on the methodologies developed to evaluate the main critical quality attributes (CQAs) necessary for liposomes market approval
Modulation of Efficient Diiodo-BODIPY in vitro Phototoxicity to Cancer Cells by Carbon Nano-Onions
Photodynamic therapy is currently one of the most promising approaches for targeted cancer treatment. It is based on responses of vital physiological signals, namely, reactive oxygen species (ROS), which are associated with diseased condition development, such as tumors. This study presents the synthesis, incorporation, and application of a diiodo-BODIPYâbased photosensitizer, based on a non-covalent functionalization of carbon nano-onions (CNOs). In vitro assays demonstrate that HeLa cells internalize the diiodo-BODIPY molecules and their CNO nanohybrids. Upon cell internalization and light exposure, the pyreneâdiiodo-BODIPY molecules induce an increase of the ROS level of HeLa cells, resulting in remarkable photomediated cytotoxicity and apoptosis. Conversely, when HeLa cells internalize the diiodo-BODIPY/CNO nanohybrids, no significant cytotoxicity or ROS basal level increase can be detected. These results define a first step toward the understanding of carbon nanomaterials that function as molecular shuttles for photodynamic therapeutics, boosting the modulation of the photosensitizer
Entomological analysis for archeological reconstruction and conservation strategies design: the mummies of Cerreto di Spoleto (Central Italy)
Insects found in archeological contexts provide useful information for reconstructing past events. In the context of funerary archeology, insects may help in reconstructing funerary practices or rituals, and in the understanding of the taphonomic processes. Furthermore, studying these insects is fundamental for developing effective conservation strategies for cultural heritage. This article focuses on the entomological investigation of four mummies (nineteenth century) discovered in the church of Santa Maria Annunziata (Cerreto di Spoleto, Central Italy). The research aimed to verify and eventually support archeological hypotheses about the four bodies and to plan an effective conservation strategy. The predominant findings were Diptera puparia and adult Coleoptera. Alongside, common species typical of the hypogean burial, such as Hydrotaea capensis and several mycetophilous (mold feeder) species were also collected. The presence of blowfly remains (Calliphoridae) would suggest that the bodies were exposed before burial
Exopolysaccharides from vaginal lactobacilli modulate microbial biofilms
Background: Exopolysaccharides (EPS) secreted by beneficial lactobacilli exert a plethora of positive activities, but little is known about their effects on biofilms of opportunistic vaginal pathogens and especially on biofilms of lactobacilli themselves. Here, the EPS produced by six vaginal lactobacilli, belonging to Lactobacillus crispatus (BC1, BC4, BC5) and Lactobacillus gasseri (BC9, BC12, BC14) species were isolated from cultural supernatants and lyophilized. Results: Lactobacillus EPS were chemically characterized in terms of monosaccharide composition by liquid chromatography (LC) analysis coupled to UV and mass spectrometry (MS) detection. Moreover, the ability of EPS (0.1, 0.5, 1 mg/mL) to stimulate the biofilm formation of lactobacilli and to inhibit the formation of pathogensâ biofilms was evaluated by crystal violet (CV) staining and 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. Isolated EPS (yields 133â426 mg/L) were heteropolysaccharides mainly composed of d-mannose (40â52%) and d-glucose (11â30%). For the first time we demonstrated that Lactobacillus EPS were able to stimulate in a dose-dependent manner (p < 0.05) the formation of biofilms of ten strains belonging to L. crispatus, L. gasseri and Limosilactobacillus vaginalis species, in terms of cell viability (84â282% increase at 1 mg/mL) and especially biofilm biomass (40â195% increase at 1 mg/mL), quantified with MTT assay and CV staining, respectively. EPS released from L. crispatus and L. gasseri were found to better stimulate the biofilms of the same producer species rather than that of other species, including producing strains themselves and other strains. Conversely, the biofilm formation of bacterial (Escherichia coli, Staphylococcus spp., Enterococcus spp. and Streptococcus agalactiae) and fungal (Candida spp.) pathogens was inhibited. The anti-biofilm activity was dose-dependent and was more marked for L. gasseri-derived EPS (inhibition up to 86%, 70%, and 58% at 1 mg/mL, 0.5 mg/mL, and 0.1 mg/mL, respectively), whilst L. crispatus-derived EPS resulted overall less efficient (inhibition up to 58% at 1 mg/mL and 40% at 0.5 mg/mL) (p < 0.05). Conclusions: Lactobacilli-derived EPS favour the biofilm formation of lactobacilli preventing, at the same time, that of opportunistic pathogens. These results support the possible employment of EPS as postbiotics in medicine as a therapeutic/preventive strategy to counteract vaginal infections
Immunotherapeutic efficacy of retargeted ohsvs designed for propagation in an ad hoc cell line
Our laboratory has pursued the generation of cancerâspecific oncolytic herpes simplex viruses (oHSVs) which ensure high efficacy while maintaining a high safety profile. Their blueprint included retargeting to a TumorâAssociated Antigen, e.g., HER2, coupled to detargeting from natural receptors to avoid offâtarget and offâtumor infections and preservation of the full complement of unmodified viral genes. These oHSVs are âfully virulent in their target cancer cellsâ. The 3rd generation retargeted oHSVs carry two distinct retargeting moieties, which enable infection of a producer cell line and of the target cancer cells, respectively. They can be propagated in an ad hoc Vero cell derivative at about tenfold higher yields than 1st generation recombinants, and more effectively replicate in human cancer cell lines. The Râ335 and Râ337 prototypes were armed with murine ILâ12. Intratumorallyâadministered Râ337 conferred almost complete protection from LLCâ 1âHER2 primary tumors, unleashed the tumor microenvironment immunosuppression, synergized with the checkpoint blockade and conferred longâterm vaccination against distant challenge tumors. In summary, the problem intrinsic to the propagation of retargeted oHSVsâwhich strictly require cells positive for targeted receptorsâwas solved in 3rd generation viruses. They are effective as immunotherapeutic agents against primary tumors and as antigenâagnostic vaccines
A dimensional approach to the psychopathology of migrants: a cross-sectional matched sample study
Objectives
Moving to a foreign country, whether out of necessity, seeking refuge, opportunity or mere curiosity, makes the individual more vulnerable to mental disorders. Even in the same conditions, many factors contribute to make migrants more susceptible to this risk than the
natives. Among many, these include linguistic and cultural differences. Unfortunately, these differences lead to a higher frequency of ânot otherwise specifiedâ diagnoses in this part of the population. This limitation can lead to greater difficulties in therapeutic choices and epidemiological assessments. This study aims to enhance the clinicianâs resources by testing a
trans-diagnostic, dimensional, psychopathological approach in the assessment of a group of migrants and a control group of natives referred to a psychiatric outpatient service.
Methods
The two groups of patients were matched for gender, age, categorical diagnosis and level of clinical severity. The SVARAD scale was used for the dimensional assessment, diagnoses were assigned according to DSM IV-TR criteria.
Results
A total of n = 224 patients, including cases (n = 112) and controls (n = 112), were recruited and agreed to participate in the study. The dimensions somatization, obsessiveness, and activation showed a significant difference between groups (p = .018; .011; .004, respectively).
Given the same degree of severity and the same diagnosis, migrants with mental disorders showed less activation and greater somatization.
Conclusions
Cross-cultural aspects and language differences, as well as the same social status of âmigrantâ, are certainly implicated in these differences. By taking these dimensional aspects into
account, clinicians could achieve greater precision in the diagnostic process and determine a significant change in the care of this risk group
Caspase 3 and 8 deficiency in human neuroblastoma
An altered apoptotic response represents a pivotal feature of cancer and is involved in cancerogenesis
and resistance to chemotherapy. So far, however, only a few studies have been devoted to survey
caspase content in malignant cell lines and primary tumor specimens. In this report, we investigated
the expression of two pivotal caspases, 3 and 8, in 63 neuroblastoma specimens by three complementary
techniques (i.e., reverse transcriptase polymerase chain reaction, immunoblotting, and immunohistochemistry).
We confirmed the frequent absence of caspase 8 expression. Moreover and most
important, we demonstrated, for the first time to our knowledge, that a significant percentage of
neuroblastomas lack caspase 3 mRNA and protein. Both caspase alterations do not show any
correlation with tumor stage and MYCN status. Immunohistochemistry showed a large number
of caspase-negative cell islets also present in positive samples. Our findings suggest that the absence of
caspases might play an important role in neuroblastoma development and resistance to apoptosisbased
treatments
First case of typhoid fever due to extensively drug-resistant Salmonella enterica serovar typhi in Italy
Typhoid fever is a potentially severe and occasionally life-threatening bacteraemic illness caused by Salmonella enterica serovar Typhi (S. Typhi). In Pakistan, an outbreak of extensively drug-resistant (XDR) S. Typhi cases began in November 2016. We report on a five-year-old boy who contracted enteric fever while travelling in Pakistan and was diagnosed after returning to Italy in September 2019. Blood culture isolated Salmonella enterica serovar Typhi that was XDR to all first-line antibiotics, including ceftriaxone and fluoroquinolones. Empiric therapy was switched to meropenem, and the patient recovered completely. Whole-genome sequencing showed that this isolate was of haplotype H58. The XDR S. Typhi clone encoded a chromosomally located resistance region and harbored a plasmid encoding additional resistance elements, including the blaCTX-M-15 extended-spectrum ÎČ-lactamase and the qnrS fluoroquinolone resistance gene. This is the first case of typhoid fever due to XDR S. Typhi detected in Italy and one of the first paediatric cases reported outside Pakistan, highlighting the need to be vigilant for future cases. While new vaccines against typhoid are in development, clinicians should consider adapting their empiric approach for patients returning from regions at risk of XDR S. Typhi outbreak with typhoid symptoms
FFF-based high-throughput sequence shortlisting to support the development of aptamer-based analytical strategies
Aptamers are biomimetic receptors that are increasingly exploited for the development of optical and electrochemical aptasensors. They are selected in vitro by the SELEX (Systematic Evolution of Ligands by Exponential Enrichment) procedure, but although they are promising recognition elements, for their reliable applicability for analytical purposes, one cannot ignore sample components that cause matrix effects. This particularly applies when different SELEX-selected aptamers and related truncated sequences are available for a certain target, and the choice of the aptamer should be driven by the specific downstream application. In this context, the present work aimed at investigating the potentialities of asymmetrical flow field-flow fractionation (AF4) with UV detection for the development of a screening method of a large number of anti-lysozyme aptamers towards lysozyme, including randomized sequences and an interfering agent (serum albumin). The possibility to work in native conditions and selectively monitor the evolution of untagged aptamer signal as a result of aptamer-protein binding makes the devised method effective as a strategy for shortlisting the most promising aptamers both in terms of affinity and in terms of selectivity, to support subsequent development of aptamer-based analytical devices. Graphical abstract: [Figure not available: see fulltext.
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