Intrapatient variation in PD-L1 expression and tumor mutational burden and the impact on outcomes to immune checkpoint inhibitor therapy in patients with non-small cell lung cancer.

BACKGROUND: PD-L1 tumor proportion score (TPS) and tumor mutational burden (TMB) are key predictive biomarkers for immune checkpoint inhibitors (ICI) efficacy in non-small cell lung cancer (NSCLC). Data on their variation across multiple samples are limited. METHODS: Patients with NSCLC and multiple PD-L1 TPS and/or TMB assessments were included. Clinicopathologic and genomic data were analyzed according to PD-L1 and TMB variation. RESULTS: In total, 402 PD-L1 sample pairs and 413 TMB sample pairs were included. Concordance between pairs was moderate for PD-L1 (ρ=0.53, P<0.0001) and high for TMB (ρ=0.80, P<0.0001). Shorter time between biopsies correlated with higher concordance in PD-L1, but not in TMB. Major increases (ΔTPS≥+50%) and decreases (ΔTPS≤-50%) in PD-L1 were observed in 9.7% and 8.0% of cases, respectively. PD-L1, but not TMB, decreased with intervening ICI (P=0.02). Acquired copy number loss of CD274, PDCD1LG2, and JAK2 were associated with major decrease in PD-L1 (q<0.05). Among patients with multiple PD-L1 assessments before ICI, cases where all samples had a PD-L1 ≥1%, compared to cases with at least one sample with PD-L1 <1% and another with PD-L1 ≥1%, achieved improved objective response rate and progression-free survival (PFS). Among patients with at least one PD-L1 <1% and one ≥1% before ICI, cases where the most proximal sample was PD-L1 ≥1% had longer median PFS compared to cases where the most proximal PD-L1 was <1%. Among patients with multiple TMB assessments before ICI, patients with a TMB ≥10 mut/Mb based on the most recent assessment, as compared to those with a TMB <10 mut/Mb, achieved improved PFS and OS to ICI; instead, no differences were observed when patients were categorized using the oldest TMB assessment. CONCLUSION: Despite intrapatient concordance in PD-L1 and TMB, variation in these biomarkers can influence ICI outcomes, warranting consideration for reassessment prior to ICI initiation when feasible.

Tumor mutational burden for the prediction of PD-(L)1 blockade efficacy in cancer: challenges and opportunities.

Tumor mutational burden (TMB) is a biomarker that measures the number of somatic mutations in a tumor's genome. TMB has emerged as a predictor of response to immune checkpoint inhibitors (ICIs) in various cancer types, and several studies have shown that patients with high TMB have better outcomes when treated with programmed death-ligand 1-based therapies. Recently, the Food and Drug Administration has approved TMB as a companion diagnostic for the use of pembrolizumab in solid tumors. However, despite its potential, the use of TMB as a biomarker for immunotherapy efficacy is limited by several factors. Here we review the limitations of TMB in predicting immunotherapy outcomes in patients with cancer and discuss potential strategies to optimize its use in the clinic.

Clonal KEAP1 mutations with loss of heterozygosity share reduced immunotherapy efficacy and low immune cell infiltration in lung adenocarcinoma.

BACKGROUND: KEAP1 mutations have been associated with reduced survival in lung adenocarcinoma (LUAD) patients treated with immune checkpoint inhibitors (ICIs), particularly in the presence of STK11/KRAS alterations. We hypothesized that, beyond co-occurring genomic events, clonality prediction may help identify deleterious KEAP1 mutations and their counterparts with retained sensitivity to ICIs. PATIENTS AND METHODS: Beta-binomial modelling of sequencing read counts was used to infer KEAP1 clonal inactivation by combined somatic mutation and loss of heterozygosity (KEAP1 C-LOH) versus partial inactivation [KEAP1 clonal diploid-subclonal (KEAP1 CD-SC)] in the Memorial Sloan Kettering Cancer Center (MSK) MetTropism cohort (N = 2550). Clonality/LOH prediction was compared to a streamlined clinical classifier that relies on variant allele frequencies (VAFs) and tumor purity (TP) (VAF/TP ratio). The impact of this classification on survival outcomes was tested in two independent cohorts of LUAD patients treated with immunotherapy (MSK/Rome N = 237; DFCI N = 461). Immune-related features were studied by exploiting RNA-sequencing data (TCGA) and multiplexed immunofluorescence (DFCI mIF cohort). RESULTS: Clonality/LOH inference in the MSK MetTropism cohort overlapped with a clinical classification model defined by the VAF/TP ratio. In the ICI-treated MSK/Rome discovery cohort, predicted KEAP1 C-LOH mutations were associated with shorter progression-free survival (PFS) and overall survival (OS) compared to KEAP1 wild-type cases (PFS log-rank P = 0.001; OS log-rank P < 0.001). Similar results were obtained in the DFCI validation cohort (PFS log-rank P = 0.006; OS log-rank P = 0.014). In both cohorts, we did not observe any significant difference in survival outcomes when comparing KEAP1 CD-SC and wild-type tumors. Immune deconvolution and multiplexed immunofluorescence revealed that KEAP1 C-LOH and KEAP1 CD-SC differed for immune-related features. CONCLUSIONS: KEAP1 C-LOH mutations are associated with an immune-excluded phenotype and worse clinical outcomes among advanced LUAD patients treated with ICIs. By contrast, survival outcomes of patients whose tumors harbored KEAP1 CD-SC mutations were similar to those with KEAP1 wild-type LUADs.

Dissecting the clinicopathologic, genomic, and immunophenotypic correlates of KRASG12D-mutated non-small-cell lung cancer.

BACKGROUND: Allele-specific KRAS inhibitors are an emerging class of cancer therapies. KRAS-mutant (KRASMUT) non-small-cell lung cancers (NSCLCs) exhibit heterogeneous outcomes, driven by differences in underlying biology shaped by co-mutations. In contrast to KRASG12C NSCLC, KRASG12D NSCLC is associated with low/never-smoking status and is largely uncharacterized. PATIENTS AND METHODS: Clinicopathologic and genomic information were collected from patients with NSCLCs harboring a KRAS mutation at the Dana-Farber Cancer Institute (DFCI), Memorial Sloan Kettering Cancer Center, MD Anderson Cancer Center, and Imperial College of London. Multiplexed immunofluorescence for CK7, programmed cell death protein 1 (PD-1), programmed death-ligand 1 (PD-L1), Foxp3, and CD8 was carried out on a subset of samples with available tissue at the DFCI. Clinical outcomes to PD-(L)1 inhibition ± chemotherapy were analyzed according to KRAS mutation subtype. RESULTS: Of 2327 patients with KRAS-mutated (KRASMUT) NSCLC, 15% (n = 354) harbored KRASG12D. Compared to KRASnon-G12D NSCLC, KRASG12D NSCLC had a lower pack-year (py) smoking history (median 22.5 py versus 30.0 py, P < 0.0001) and was enriched in never smokers (22% versus 5%, P < 0.0001). KRASG12D had lower PD-L1 tumor proportion score (TPS) (median 1% versus 5%, P < 0.01) and lower tumor mutation burden (TMB) compared to KRASnon-G12D (median 8.4 versus 9.9 mt/Mb, P < 0.0001). Of the samples which underwent multiplexed immunofluorescence, KRASG12D had lower intratumoral and total CD8+PD1+ T cells (P < 0.05). Among 850 patients with advanced KRASMUT NSCLC who received PD-(L)1-based therapies, KRASG12D was associated with a worse objective response rate (ORR) (15.8% versus 28.4%, P = 0.03), progression-free survival (PFS) [hazard ratio (HR) 1.51, 95% confidence interval (CI) 1.45-2.00, P = 0.003], and overall survival (OS; HR 1.45, 1.05-1.99, P = 0.02) to PD-(L)1 inhibition alone but not to chemo-immunotherapy combinations [ORR 30.6% versus 35.7%, P = 0.51; PFS HR 1.28 (95%CI 0.92-1.77), P = 0.13; OS HR 1.36 (95%CI 0.95-1.96), P = 0.09] compared to KRASnon-G12D. CONCLUSIONS: KRASG12D lung cancers harbor distinct clinical, genomic, and immunologic features compared to other KRAS-mutated lung cancers and worse outcomes to PD-(L)1 blockade. Drug development for KRASG12D lung cancers will have to take these differences into account.

Antibiotic-exposed patients with non-small-cell lung cancer preserve efficacy outcomes following first-line chemo-immunotherapy.

BACKGROUND: Prior antibiotic therapy (pATB) is known to impair efficacy of single-agent immune checkpoint inhibitors (ICIs), potentially through the induction of gut dysbiosis. Whether ATB also affects outcomes to chemo-immunotherapy combinations is still unknown. PATIENTS AND METHODS: In this international multicentre study, we evaluated the association between pATB, concurrent ATB (cATB) and overall survival (OS), progression-free survival (PFS) and objective response rate (ORR) in patients with non-small-cell lung cancer (NSCLC) treated with first-line chemo-immunotherapy at eight referral institutions. RESULTS: Among 302 patients with stage IV NSCLC, 216 (71.5%) and 61 (20.2%) patients were former and current smokers, respectively. Programmed death-ligand 1 tumour expression in assessable patients (274, 90.7%) was ≥50% in 76 (25.2%), 1%-49% in 84 (27.9%) and <1% in 113 (37.5%). Multivariable analysis showed pATB-exposed patients to have similar OS {hazard ratio (HR) = 1.42 [95% confidence interval (CI): 0.91-2.22]; P = 0.1207} and PFS [HR = 1.12 (95% CI: 0.76-1.63); P = 0.5552], compared to unexposed patients, regardless of performance status. Similarly, no difference with respect to ORR was found across pATB exposure groups (42.6% versus 57.4%, P = 0.1794). No differential effect was found depending on pATB exposure duration (≥7 versus <7 days) and route of administration (intravenous versus oral). Similarly, cATB was not associated with OS [HR = 1.29 (95% CI: 0.91-1.84); P = 0.149] and PFS [HR = 1.20 (95% CI: 0.89-1.63); P = 0.222] when evaluated as time-varying covariate in multivariable analysis. CONCLUSIONS: In contrast to what has been reported in patients receiving single-agent ICIs, pATB does not impair clinical outcomes to first-line chemo-immunotherapy of patients with NSCLC. pATB status should integrate currently available clinico-pathologic factors for guiding first-line treatment decisions, whilst there should be no concern in offering cATB during chemo-immunotherapy when needed.

Second primary neoplasms in patients with lung and gastroenteropancreatic neuroendocrine neoplasms: Data from a retrospective multi-centric study.

BACKGROUND: Patients with sporadic neuroendocrine neoplasms may exhibit a higher risk of a second primary tumor than the general population. AIM: This study aimed to analyze the occurrence of second primary malignancies. METHODS: A retrospective cohort of 2757 patients with sporadic lung and gastro-entero-pancreatic neuroendocrine neoplasms, managed at eight Italian tertiary referral Centers, was included. RESULTS: Between 2000 and 2019, a second primary malignancy was observed in 271 (9.8%) neuroendocrine neoplasms patients with 32 developing a third tumor. There were 135 (49.8%) females and the median age was 64 years. The most frequent locations of the second tumors were breast (18.8%), prostate (12.5%), colon (9.6%), blood tumors (8.5%), and lung (7.7%). The second primary tumor was synchronous in 19.2% of cases, metachronous in 43.2%, and previous in 37.6%. As concerned the neuroendocrine neoplasms, the 5- and 10-year survival rates were 87.8% and 74.4%, respectively. PFS for patients with a second primary malignancy was shorter than for patients without a second primary malignancy. Death was mainly related to neuroendocrine neoplasms. CONCLUSION: In NEN patients the prevalence of second primary malignancies was not negligible, suggesting a possible neoplastic susceptibility. Overall survival was not affected by the occurrence of a second primary malignancy.

Risk of preoperative understaging of duodenal neuroendocrine neoplasms: a plea for caution in the treatment strategy.

PURPOSE: Pretreatment staging is the milestone for planning either surgical or endoscopic treatment in duodenal neuroendocrine neoplasms (dNENs). Herein, a series of surgically treated dNEN patients was evaluated to assess the concordance between the pre- and postsurgical staging. METHODS: Retrospective analysis of patients with a histologically confirmed diagnosis of dNENs, who underwent surgical resection observed at eight Italian tertiary referral centers. The presurgical TNM stage, based on the radiological and functional imaging, was compared with the pathological TNM stage, after surgery. RESULTS: From 2000 to 2019, 109 patients were included. Sixty-six patients had G1, 26 a G2, 7 a G3 dNEN (Ki-67 not available in 10 patients). In 46/109 patients (42%) there was disagreement between the pre- and postsurgical staging, being it understaged in 42 patients (38%), overstaged in 4 (3%). As regards understaging, in 25 patients (22.9%), metastatic loco-regional nodes (N) resulted undetected at both radiological and functional imaging. Understaging due to the presence of distal micrometastases (M) was observed in 2 cases (1.8%). Underestimation of tumor extent (T) was observed in 12 patients (11%); in three cases the tumor was understaged both in T and N extent. CONCLUSIONS: Conventional imaging has a poor detection rate for loco-regional nodes and micrometastases in the presurgical setting of the dNENs. These results represent important advice when local conservative approaches, such as endoscopy or local surgical excision are considered and it represents a strong recommendation to include endoscopic ultrasound in the preoperative tools for a more accurate local staging.

Engineering approaches for drug delivery systems production and characterization.

To find and to test the therapeutic effectiveness (and the limited adverse effects) of a new drug is a long and expensive process. It has been estimated a period of ten years and an expense of the order of one billion USD are required. Meanwhile, even if a promising molecule has been identified, there is the need for operative methods for its delivery. The extreme case is given by gene therapy, in which molecules with tremendous in-vitro efficacy cannot be used in practice because of the lack in useful vector systems to deliver them. Most of the recent efforts in pharmaceutical sciences are focused on the development of novel drug delivery systems (DDSs). In this review, the work done recently on the development and testing of novel DDSs, with particular emphasis on the results obtained by European research, is summarized. In the first section of the review the DDSs are analyzed accordingly with their scale-size: starting from nano-scale (liposomes, nanoparticles), up to the micro-scale (microparticles), until the macroscopic world is reached (granules, matrix systems). In the following two sections, non-conventional testing methods (mechanical methods and bio-relevant dissolution methods) are presented; at last, the importance of mathematical modeling to describe drug release and related phenomena is reported.

Clinicopathological and genomic correlates of programmed cell death ligand 1 (PD-L1) expression in nonsquamous non-small-cell lung cancer.

BACKGROUND: Programmed cell death ligand 1 (PD-L1) tumor proportion score (TPS) is the primary clinically-available biomarker of response to immunotherapy in non-small-cell lung cancer (NSCLC), but factors associated with PD-L1 expression are not well understood. MATERIALS AND METHODS: Consecutive nonsquamous NSCLCs with successful PD-L1 assessment and targeted next-generation sequencing were included in this retrospective study. Clinicopathological characteristics, gene mutations, and copy number changes in gene and chromosomal arms were compared among three PD-L1 expression groups: negative (TPS < 1%), low (TPS 1%-49%), and high (TPS ≥ 50%). A Q-value <0.25 was considered significant after multiple comparisons correction. RESULTS: A total of 909 nonsquamous NSCLCs were included. High PD-L1 expression compared with low and negative PD-L1 expression was associated with increased tobacco exposure (median pack-years: 25 versus 20 versus 20, respectively; P = 0.01), advanced stage at diagnosis (76% versus 67% versus 61% with advanced stage of disease, respectively; P < 0.001), and higher tumor mutational burden (TMB) (median 12.2 versus 10.6 versus 10.6 mutations/megabase, respectively; P < 0.001). Negative PD-L1 expression when compared with high PD-L1 expression was associated with: mutations in STK11 (19% versus 5%; Q < 0.001), EGFR (22% versus 11%; Q < 0.001), CTNNB1 (4.3% versus 0.4%; Q = 0.04), APC (5% versus 1%; Q = 0.17), and SMARCA4 (9% versus 4%; Q = 0.20); copy number loss of CD274 (PD-L1, 28% versus 6%; Q < 0.001), PDCD1LG2 (PD-L2, 28% versus 6%; Q < 0.001), and JAK2 genes (27% versus 7%; Q < 0.001), loss of chromosomal arm 9p (23% versus 10%; Q = 0.04), and gain of 1q (46% versus 21%; Q < 0.001). High PD-L1 expression compared with negative PD-L1 expression was associated with copy number gain of CD274 (11% versus 3%; Q = 0.01) and PDCD1LG2 (11% versus 3%; Q = 0.01). NSCLCs with CD274 loss, compared with those without loss, had a lower response rate (23% versus 9%; P = 0.006) and shorter progression-free survival (3.3 versus 2.0 months; P = 0.002) on immunotherapy. CONCLUSIONS: PD-L1 expression is associated with specific genomic alterations and clinicopathologic characteristics in nonsquamous NSCLC.

The functioning side of the pancreas: a review on insulinomas.

PURPOSE: Insulinomas are a rare type of neuroendocrine tumors, originating in the pancreas, difficult to diagnose and to treat. Due to its rarity, insulinomas are a not well-known pathological entity; thus, the diagnostic process is frequently a medical challenge with many possible differential diagnoses. The diagnostic process varies between non-invasive procedures, such as the fasting test or imaging techniques, and invasive ones. Insulinomas are rarely malignant, but the glycemic imbalance correlated with this tumor can frequently alter the quality of life of the patients and the consequent hypoglycemia can be extremely dangerous. Moreover, insulinomas can be associated with different genetic syndromes, such as Multiple Endocrine Neoplasia 1, accompanied by other specific symptoms. There are many different treatment strategies, depending on the need to control symptoms or control diseases progression, the only curative one being surgery. METHODS AND RESULTS: We reviewed the evidences present in the literature on insulinomas and reported its main clinical characteristics and management strategies. CONCLUSION: The aim of this review of the literature is to present the current knowledge on insulinomas, exploring the main clinical characteristics, the diagnostic tools, and the therapeutic strategies.

Hydrogels: experimental characterization and mathematical modelling of their mechanical and diffusive behaviour.

Hydrogels are materials widely used in countless applications, particularly in the biomedical, pharmaceutical, and nutraceutical fields, because of their biocompatibility and their mechanical and transport properties. Several approaches are known to evaluate their properties, but only a few approaches are under development to mathematically describe their behaviour, in terms of how the materials answer to mechanical stimuli and how incorporated active substances are released. In this review, the main properties of hydrogels are summarized and the structure-property relationships are investigated (i.e. how the macromolecular structure influences the properties of macroscopic samples made of hydrogels). A selection criterion is proposed based on the comparison of three characteristic times: relaxation time, diffusion time, and process time. Then, the most common experimental methods to investigate the hydrogel properties are summarized, along with the state-of-the-art of mathematical modelling, with reference to the mechanical and transport properties of hydrogels, with particular attention to the viscoelastic and poroelastic behaviours. Last but not least, some case histories which can be classified as viscoelastic, poroelastic, or poroviscoelastic behaviours are presented.

Determination of Mammalian Target of Rapamycin Hyperactivation as Prognostic Factor in Well-Differentiated Neuroendocrine Tumors.

PURPOSE: To evaluate the role of the activation of mTOR (phosphorylated mTOR, p-mTOR) and the expression SSTR2A and IGF-1R as prognostic factor in well-differentiated neuroendocrine tumors. METHODS: A retrospective study was conducted on data from patients with diagnosis of neuroendocrine tumor originated from pancreas (pNET) or gastrointestinal tract (stomach, appendix, and ileus; GI-NET) made between January 2003 and December 2004 and followed up at our institution. Archival material should be available for revision according to WHO 2010 neuroendocrine tumor classification and for p-mTOR, SSTR2A, and IGF-1R immunostaining, calculating a quantitative score (QS). We evaluated clinical, pathological, and immunohistochemistry features for association with the presence of advanced disease at diagnosis and disease relapse in patients who have undergone radical surgery. RESULTS: Archival material from 64 patients was analyzed (37 pNETs and 27 GI-NETs). In these patients, G2 grading, low SSTR2A QS, and high p-mTOR QS were associated with advanced disease at diagnosis at multivariate analysis. Risk of recurrence in 49 patients with R0-resected tumors was higher for G2 grading, stage IIIB-IV, low IGF-1R QS, and high p-mTOR QS at univariate analysis. CONCLUSIONS: With the limits of retrospective data, activation of m-TOR is correlated with advanced disease at diagnosis and with shorter disease-free survival after R0 resection. Validation through prospective studies is needed.

Recovery from vegetative state of patients with a severe brain injury: a 4-year real-practice prospective cohort study.

Patients who have suffered severe traumatic or nontraumatic brain injuries can show a progressive recovery, transitioning through a range of clinical conditions. They may progress from coma to a vegetative state (VS) and/or a minimally conscious state (MCS). A longer duration of the VS is known to be related to a lower probability of emergence from it; furthermore, the literature seems to lack evidence of late improvements in these patients. This real-practice prospective cohort study was conducted in inpatients in a VS following a severe brain injury, consecutively admitted to a vegetative state unit (VSU). The aim of the study was to assess their recovery in order to identify variables that might increase the probability of a VS patient transitioning to MCS. Rehabilitation treatment included passive joint mobilisation and helping/placing patients into an upright sitting position on a tilt table. All the patients underwent a specific assessment protocol every month to identify any emergence, however late, from the VS. Over a 4-year period, 194 patients suffering sequelae of a severe brain injury, consecutively seen, had an initial Glasgow Coma Scale score ≤ 8. Of these, 63 (32.5%) were in a VS, 84 (43.3%) in a MCS, and 47 (24.2%) in a coma; of the 63 patients admitted in a VS, 49 (57.1% males and 42.9% females, mean age 25.34 ± 19.12 years) were transferred to a specialist VSU and put on a slow-to-recover brain injury programme. Ten of these 49 patients were still in a VS after 36 months; of these 10, 3 recovered consciousness, transitioning to a MCS, 2 died, and 5 remained in a VS during the last 12 months of the observation. Univariate analysis identified male sex, youth, a shorter time from onset of the VS, diffuse brain injury, and the presence of status epilepticus as variables increasing the likelihood of transition to a MCS. Long-term monitoring of patients with chronic disorders of consciousness should be adequately implemented in order to optimise their access to rehabilitation services.

Analysis of Italian regulations on pathways of care for patients in a vegetative or minimally conscious state.

Different rehabilitation models for persons diagnosed with disorders of consciousness have been proposed in Europe during the last decade. In Italy, the Ministry of Health has defined a national healthcare model, although, to date, there is a lack of information on how this has been implemented at regional level. The INCARICO project collected information on different regional regulations, analysing ethical aspects and mapping care facilities (numbers of beds and medical units) in eleven regional territories. The researchers found a total of 106 laws; differences emerged both between regions and versus the national model, showing that patients with the same diagnosis may follow different pathways of care. An ongoing cultural shift from a treatment-oriented medical approach towards a care-oriented integrated biopsychosocial approach was found in all the welfare and healthcare systems analysed. Future studies are needed to explore the relationship between healthcare systems and the quality of services provided.

Modeling the modified drug release from curved shape drug delivery systems - Dome Matrix®.

The controlled drug release from hydrogel-based drug delivery systems is a topic of large interest for research in pharmacology. The mathematical modeling of the behavior of these systems is a tool of emerging relevance, since the simulations can be of use in the design of novel systems, in particular for complex shaped tablets. In this work a model, previously developed, was applied to complex-shaped oral drug delivery systems based on hydrogels (Dome Matrix®). Furthermore, the model was successfully adopted in the description of drug release from partially accessible Dome Matrix® systems (systems with some surfaces coated). In these simulations, the erosion rate was used asa fitting parameter, and its dependence upon the surface area/volume ratio and upon the local fluid dynamics was discussed. The model parameters were determined by comparison with the drug release profile from a cylindrical tablet, then the model was successfully used for the prediction of the drug release from a Dome Matrix® system, for simple module configuration and for module assembled (void and piled) configurations. It was also demonstrated that, given the same initial S/V ratio, the drug release is independent upon the shape of the tablets but it is only influenced by the S/V evolution. The model reveals itself able to describe the observed phenomena, and thus it can be of use for the design of oral drug delivery systems, even if complex shaped.

PoroViscoElastic model to describe hydrogels' behavior.

Hydrogels are three-dimensional, cross-linked hydrophilic polymeric network able of absorb large amount of water. The mechanics of these systems is strictly coupled with the water transport resulting in the peculiar behavior known as poroviscoelasticy. This can be considered as sum of the viscoelastic behavior of the polymeric network and the poroelastic behavior caused by the water movement within the hydrogel. In this work a 3D monophasic model able to depict the poroviscoelastic behavior of these systems, within the field of nonlinear solid mechanics, is developed. The mass and momentum balances equations, supported by constitutive equations from non-equilibrium thermodynamics and by initial and boundary conditions, is implemented through the weak formulation in a commercial FEM-based software. A parametric study is performed in order to assess the relative importance of the model parameters on hydrogels' behavior.

Ultrasonic energy in liposome production: process modelling and size calculation.

The use of liposomes in several fields of biotechnology, as well as in pharmaceutical and food sciences is continuously increasing. Liposomes can be used as carriers for drugs and other active molecules. Among other characteristics, one of the main features relevant to their target applications is the liposome size. The size of liposomes, which is determined during the production process, decreases due to the addition of energy. The energy is used to break the lipid bilayer into smaller pieces, then these pieces close themselves in spherical structures. In this work, the mechanisms of rupture of the lipid bilayer and the formation of spheres were modelled, accounting for how the energy, supplied by ultrasonic radiation, is stored within the layers, as the elastic energy due to the curvature and as the tension energy due to the edge, and to account for the kinetics of the bending phenomenon. An algorithm to solve the model equations was designed and the relative calculation code was written. A dedicated preparation protocol, which involves active periods during which the energy is supplied and passive periods during which the energy supply is set to zero, was defined and applied. The model predictions compare well with the experimental results, by using the energy supply rate and the time constant as fitting parameters. Working with liposomes of different sizes as the starting point of the experiments, the key parameter is the ratio between the energy supply rate and the initial surface area.

Therapeutic potential of nucleic acid-based drugs in coronary hyper- proliferative vascular diseases.

The thickening of the vessel wall (intimal hyperplasia) is a pathological process which often follows revascularization approaches such as transluminal angioplasty and artery bypass graft, procedures used to re-vascularize stenotic artery. Despite the significant improvements in the treatment of intimal hyperplasia obtained in the last years, the problem has not completely solved. Nucleic acid based-drugs (NABDs) represent an emergent class of molecules with potential therapeutic value for the treatment of intimal hyperplasia. NABDs of interest in the field of intimal hyperplasia are: ribozymes, DNAzymes, antisense oligonucleotides, decoy oligonucleotides, small interfering RNAs and micro interfering RNAs. These molecules can recognize, in a sequencespecific fashion, a target which, depending on the different NABDs, can be represented by a nucleic acid or a protein. Upon binding, NABDs can down-modulate the functions of the target (mRNA/proteins) and thus they are used to impair the functions of disease-causing biological molecules.In spite of the great therapeutic potential demonstrated by NABDs in many experimental model of intima hyperplasia, their practical use is hindered by the necessity to identify optimal delivery systems to the vasculature. In the first part of this review a brief description of the clinical problem related to intima hyperplasia formation after revascularization procedures is reported. In the second part, the attention is focused on the experimental evidences of NABD therapeutic potential in the prevention of intimal hyperplasia. Finally, in the third part, we will describe the strategies developed to optimize NABD delivery to the diseased vessel.

Rehabilitation of acquired brain injuries: a multicentric prospective survey.

BACKGROUND: The rehabilitation of the persons with Severe Acquired Brain Injury (ABI) is an important concern to be approached with a comprehensive program aimed to improve the recovery of patients.The efficacy of an early and intensive rehabilitation program has been shown in large number of studies. Few studies focused on the prevalence of TBI and the data are often extrapolated in indirect ways. AIM: An analysis of the demographic characteristics of the population included in the GISCAR (Gruppo Italiano per lo Studio delle Gravi Cerebrolesioni Acquisite e Riabilitazione- Italian Group for the Study of the severe ABI) database, type and conditions associated to the index event; the treatment administered during hospitalization; and the prognosis according to outcome measures. DESIGN: The study was an observational prospective survey looking at management of ABI (both traumatic and non-traumatic). SETTING: In hospital rehabilitation. POPULATION: Patients consecutively admitted in each of the 52 GISCAR centres. METHODS: Every centre included a consecutive cohort and recorded demographic data and index event characteristics. RESULTS: In the study population were included 2626 subjects suffering of a severe ABI. The difference of length of stay (LOS) was significantly different with 67.5 days for traumatic patients compared to the 80 days of non traumatic ones. In the study population the probability of discharge at home is significantly greater for the traumatic condition (odds ratio 0,4587; CI 0.3671-0.5731). The overall benefit of the rehabilitative treatment was encountered in a net gain in all disability scores taken into account: LCF classes; DRS as well as GOS scores. At discharge the main destination for severe ABI patients was home (67.2%). CONCLUSIONS: A large number of patients admitted in Italian rehabilitative facilities for a severe ABI suffered from a TBI, more often these subjects were young male victims of road accident. The majority of subjects during the rehabilitative hospitalization demonstrated a significant recovery. CLINICAL REHABILITATION IMPACT: Considering the evidence of an early treatment benefit the delay ofthe rehabilitation program start is far from being satisfactory. The high frequency of the home discharge indicate a good compliance of national family network.