Soft Perfusable Device to Culture Skeletal Muscle 3D Constructs in Air

Devices for in vitro culture of three-dimensional (3D) skeletal muscle tissues have multiple applications, including tissue engineering and muscle-powered biorobotics. In both cases, it is crucial to recreate a biomimetic environment by using tailored scaffolds at multiple length scales and to administer prodifferentiative biophysical stimuli (e.g., mechanical loading). On the contrary, there is an increasing need to develop flexible biohybrid robotic devices capable of maintaining their functionality beyond laboratory settings. In this study, we describe a stretchable and perfusable device to sustain cell culture and maintenance in a 3D scaffold. The device mimics the structure of a muscle connected to two tendons: Tendon-Muscle-Tendon (TMT). The TMT device is composed of a soft (E ∼ 6 kPa) porous (pore diameter: ∼650 μm) polyurethane scaffold, encased within a compliant silicone membrane to prevent medium evaporation. Two tendon-like hollow channels interface the scaffold with a fluidic circuit and a stretching device. We report an optimized protocol to sustain C2C12 adhesion by coating the scaffold with polydopamine and fibronectin. Then, we show the procedure for the soft scaffold inclusion in the TMT device, demonstrating the device's ability to bear multiple cycles of elongations, simulating a protocol for cell mechanical stimulation. By using computational fluid dynamic simulations, we show that a flow rate of 0.62 mL/min ensures a wall shear stress value safe for cells (<2 Pa) and 50% of scaffold coverage by an optimal fluid velocity. Finally, we demonstrate the effectiveness of the TMT device to sustain cell viability under perfusion for 24 h outside of the CO₂ incubator. We believe that the proposed TMT device can be considered an interesting platform to combine several biophysical stimuli, aimed at boosting skeletal muscle tissue differentiation in vitro, opening chances for the development of muscle-powered biohybrid soft robots with long-term operability in real-world environments.

Optimal low-intensity pulsed ultrasound stimulation for promoting anti-inflammatory effects in macrophages

In this paper, we stimulated M1-like macrophages (obtained from U937 cells) with low-intensity pulsed ultrasound (LIPUS) to lower pro-inflammatory cytokine production. A systematic screening of different frequencies, intensities, duty cycles, and exposure times was performed. The optimal stimulation conditions leading to a marked decrease in the release of inflammatory cytokines were determined to be 38 kHz, 250 mW/cm², 20%, and 90 min, respectively. Using these parameters, we verified that up to 72 h LIPUS did not affect cell viability, resulting in an increase in metabolic activity and in a reduction of reactive oxygen species (ROS) production. Moreover, we found that two mechanosensitive ion channels (PIEZO1 and TRPV1) were involved in the LIPUS-mediated cytokine release modulation. We also assessed the role of the nuclear factor κB (NF-κB) signaling pathway and observed an enhancement of actin polymerization. Finally, transcriptomic data suggested that the bioeffects of LIPUS treatment occur through the modulation of p38 MAPK signaling pathway.

Low-intensity pulsed ultrasound increases neurotrophic factors secretion and suppresses inflammation in in vitro models of peripheral neuropathies

OBJECTIVE

In this study, we aimed to verify the beneficial effects of low-intensity pulsed ultrasound (LIPUS) stimulation on two cell types: H2O2-treated RSC96 Schwann cells and THP-1 macrophages, used to model neuropathic inflammation. &#xD;Approach: Using a set-up guaranteeing a fine control of the ultrasound dose at the target, different frequencies (38 kHz, 1 MHz, 5 MHz) and different intensities (20, 100, 500 mW/cm2) were screened to find the most effective experimental conditions for triggering beneficial effects on metabolic activity and release of neurotrophic cytokines (-NGF, BDNF, GDNF) of RSC96 cells. The combination of parameters resulting the optimal one was applied to evaluate anti-inflammatory effects in terms of ROS and TNF- production, also investigating a possible anti-oxidant activity and mechanotransduction pathway for the anti-inflammatory process. The same optimal combination of parameters was then applied to THP-1 cells, differentiated into M1 and M2 phenotypes, to assess the effect on the expression and release of pro-inflammatory markers (TNF-, IL-1, IL-6, IL-8) and anti-inflammatory ones (IL-10 and CD206). &#xD;Main results: 5 MHz and 500 mW/cm2 were found as the optimal stimulation parameters on RSC96 cells Such parameters were also found to suppress ROS and TNF- in the same cell line, thus highlighting a possible anti-inflammatory effect, involving the NF-kB pathway An anti-oxidant effect induced by LIPUS was also observed. Finally, the same LIPUS parameters did not induce any differentiation towards the M1 phenotype of THP-1 cells, whereas they decreased TNF- and IL-8 gene expression, reduced IL-8 cytokine release and increased IL-10 cytokine release in M1-polarized THP-1 cells.&#xD;Significance: This study represents the first step towards the use of precisely controlled low-intensity pulsed ultrasound for the treatment of peripheral neuropathies. &#xD.

Cross-sectional serosurvey of Coxiella burnetii in healthy cattle and sheep from extensive grazing system in central Italy

A cross-sectional survey was carried out to estimate the seroprevalence of Coxiella burnetii in extensively grazed cattle and sheep from central Italy and to identify the related risk factors. Data on notified human Q fever cases in the area were also collected and described. A two-stage cluster sampling was performed. A total of 5083 animals (2210 cattle; 2873 sheep) belonging to 186 farms (92 herds; 94 flocks) were tested for the presence of antibodies against C. burnetii using a commercial enzyme-linked immunosorbent assay kit. The prevalence at the animal-level resulted three times higher in sheep compared to cattle (37.8% vs. 12.0%; χ2 = 270.10, P < 0.001). The prevalence at the herd-level was also higher in sheep than in cattle (87.2% vs. 68.5%; χ2 = 9.52, P < 0.01). The multivariate analysis showed a higher risk of seropositivity for cattle aged 67-107 months (OR 2.79, 95% CI 1.86-4.18), cattle >107 months of age (OR 2.07, 95% CI 1.36-3.14) and mixed breed cattle (OR 1.74, 95% CI 1.11-2.72). A herd size >92 animals was recognized as herd-level risk factor in cattle (OR 6.88, 95% CI 1.67-28.37). The risk of being seropositive was double in sheep belonging to flocks >600 animals (odds ratio (OR) 2.04, 95% CI 1.63-2.56). Sheep were confirmed to be the most exposed species. Nevertheless, the prevalence observed in cattle also suggests the potential involvement of this species in the circulation of the pathogen in the area. Seven confirmed human Q fever cases were reported. In five out of seven cases there was at least one exposed herd within a 5 km buffer. Even though the source of the infection was not identified, the possibility of C. burnetii circulating in the livestock and human population in the study area cannot be overlooked. The integration between veterinary and human surveillance will be crucial to understand the spread of this zoonosis and to support the adoption of appropriate control measures.

Growth trend during the first six months of life in male infants with different type of feeding

AIM

The aim of the study was to assess the differences in the growth trend of male infants fed with human milk (HM), formula feeding (FF) and both (HM+FF), focusing the attention on weight increase in the first six months of life.

METHODS

We enrolled 146 healthy male infants born from a spontaneous delivery; exclusion criteria were all conditions that required parenteral nutrition; the follow-up visits were at 1, 2, 3, 4, 5, 6 months of life. All infants were subsequently divided into three groups depending on the three feeding type (HM, FF, HM+FF) and then in other three subgroups depending on birth weight and gestational age (A, B, C).

RESULTS

The three feeding type groups appeared homogeneous for gestational age and birth weight at every time of follow-up. The weight differences between subgroup A, B, C were not statistically significant, showing a regular growth trends.

CONCLUSION

It is possible to assess the nutritional balance and the adequacy in composition of formula. This suggests that, in our population, the possible factors that could influence the rapid weight gain, characterized by a peak in the growth trend profile, do not concern the nutrition during the first six months of life but at most the weaning.

In vitro effect of gold and silver nanoparticles on human spermatozoa

The cytotoxicity of Au/Ag nanoparticles (NPs) on human spermatozoa was investigated in vitro. Semen from donors were incubated (37 °C, 60'-120') with 30, 60, 125, 250 and 500 μM Au/Ag-NPs. Sperm motility was evaluated following WHO guidelines; sperm viability was assessed with eosin Y test. Au-NPs were characterised and localised with field emission gun-based scanning transmission electron microscope/energy dispersive spectroscopy and transmission electron microscopy. Both tested NPs exerted a significant dose-dependent effect on motility and viability of human spermatozoa (P < 0.001). Ag-NPs seem to show a slightly elevated toxicity although not significant (P > 0.05). Au-NPs were localised in spermatozoa, whereas Ag-NPs were undetectable. In conclusion, Au-NPs and Ag-NPs do not appear to be harmful for human spermatozoa up to high concentrations (250-500 μM) that are probably difficult to reach in vivo. It is mandatory to explore the genotoxic effect of NPs in germ cells.

Validation of a diagnostic score for the diagnosis of autoinflammatory diseases in adults

Most autoinflammatory disorders typically come out in the pediatric population, although a limited number of patients may experience disease onset during adulthood. To date, a late disease onset has been described only in familial Mediterranean fever, caused by mutations in the MEFV gene, and in tumor necrosis factor receptor-associated periodic syndrome, caused by mutations in the TNFRSF1A gene. The relative rarity and lack of information on adult-onset autoinflammatory diseases make it likely that mutations will be found in an even smaller percentage of cases. With the aim of improving the genetic diagnosis in adults with suspected autoinflammatory disorders, we recently identified a set of variables related to the probability of detecting gene mutations in MEFV and TNFRSF1A and, in addition, we have also proposed a diagnostic score for identifying those patients at high risk of carrying mutations in these genes. In the present study we evaluated the preliminary score sensitivity and specificity on a wider number of patients in order to validate the goodness of fit of the model. Two hundred and nineteen consecutive patients with a clinical history of periodic fever attacks were screened for mutations in MEFV and TNFRSF1A genes; detailed information about family/personal history and clinical manifestations were also collected. For the validation of the score we considered data both from the 110 patients used to build the preliminary diagnostic score and from the additional 219 patients enrolled in the present study, for a total number of 329 patients. Early age at disease onset, positive family history for recurrent fever episodes, thoracic pain, abdominal pain and skin rash, which are the variables that had previously been shown to be significantly associated with a positive genetic test result (12), were used for validation. On univariate analysis the associations with a positive genetic test were: age at onset (odds ratio [OR] 0.43, p=0.003), positive family history for recurrent fever episodes (OR 5.81, p<0.001), thoracic pain (OR 3.17, p<0.001), abdominal pain (OR 3.80, p<0.001) and skin rash (OR 1.58, p=0.103). The diagnostic score was calculated using the linear combination of the estimated coefficients of the logistic multivariate model (cut-off equals to 0.24) revealing good sensitivity (0.778) and good specificity (0.718). In conclusion, our score may serve in the diagnostic evaluation of adult patients presenting with recurrent fever episodes suspected of having an autoinflammatory disorder, helping identify the few subjects among them who may be carriers of mutations in MEFV and TNFRSF1A genes.

Development and preliminary validation of a diagnostic score for identifying patients affected with adult-onset autoinflammatory disorders

To date, the rate of detection of autoinflammatory gene mutations in patients suspected of having an autoinflammatory disorder is very low. However, most of these data refer to pediatric populations. The relative rarity and lack of information on adult-onset autoinflammatory diseases make it likely that mutations will be found in an even smaller percentage of cases. Our aim was to develop and validate a set of variables for predicting the risk that a given adult patient presenting with recurrent fever episodes carries mutations in the MEFV or TNFRSF1A genes, in order to increase the probability of obtaining positive results on genetic testing. One hundred and ten consecutive patients with a clinical history of periodic fever attacks were screened for mutations in the TNFRSF1A and the MEFV genes. The mean age at disease onset was 27.85 years. Detailed information about each patient?s family history, personal history, and clinical manifestations were retrospectively collected. A diagnostic score was constructed based on univariate and multivariate analysis in a randomly-selected dataset (training set; n=40). The score was validated on an independent set of the remaining patients (validation set; n=70). Age at onset (odds ratio 0.958, P =0.050), positive family history of recurrent fever episodes (OR 5.738, P = 0.006 ), thoracic pain (OR 7.390, P = 0.002), abdominal pain (OR 2.853, P = 0.038) and skin involvement (OR 8.241, P = 0.003) were independently correlated with a positive genetic test result. A diagnostic score was calculated using the linear combination of the estimated coefficients of the logistic model (cut off equal to 0.24) revealing high sensitivity (0.94), high specificity (0.94) and high accuracy (0.94). We have identified variables that appear to be strongly related to the probability of detecting gene mutations in MEF and TNFRSF1A in adults, thus improving the evaluation of patients with suspected autoinflammatory disorders.

Proctorship for CAS training: a pilot study of safety and reproducibility

AIM

The literature continues reporting a high complication rate for carotid artery stenting (CAS) during the learning-curve phase (LCP). The aim of this study was to report a simple and reproducible method designed to improve CAS results during the LCP.

METHODS

Between February 2007 and December 2009, a qualified vascular surgeon ran a proctorship program for CAS. The program was divided into four practical phases: in the teaching phase (a) the first 20 CAS were performed by the proctor assisted by a trainee surgeon; in the training phase (b) for the 21st to the 50th CAS the trainee surgeon was supervised by the proctor; in the skilled phase (c), between the 51st and the 80th procedure, a trainee surgeon performed CAS while the proctor was scrubbed-in but operating only on demand; in the final phase (d), following the 81st CAS, the procedure was performed without the proctor's presence. The inclusion criterion was carotid stenosis ≥70% and patient selection was performed for the first 40 cases based on patient and lesion characteristics. The procedure for CAS was standardized.

RESULTS

Four trainees performed 604 CASs in two centers. The procedural success rate of CAS was 98.8% (N.=594/604) without any differences among the four trainees (P=0.902). The overall TIA, myocardial infarction, minor, major and fatal stroke rate at 30 days was respectively 1.7% (N.=10), 0.8% (N.=5), 1.2% (N.=7), 0.64% (N.=4) and 0.3% (N.=2). The effectiveness of this program was demonstrated by a significant decrease in the proctor's intervention between phase b and phase c (P<0.001) and by a similar trend in the complication rate achieved by the four trainees, in all phases and centers (P=0.075 and 0.788, respectively).

CONCLUSION

This preliminary experience of a proctorship program in the LCP, together with patient selection and standardization of the procedure and materials used, seems to be safe and reproducible. Moreover, possibly randomized, studies comparing different CAS training techniques are needed in order to validate our findings.

Carotid highly-calcified de novo stenosis and cutting-balloon angioplasty: a tool to prevent haemodynamic depression?

AIM

Severe highly-calcified de-novo lesions of carotid arteries are important predictors of haemodynamic depression (HD) after carotid artery stenting (CAS). Cutting-balloon angioplasty (CBA) using low-inflation pressures has been described as an effective method to achieve important luminal gain and avoid HD.

METHODS

from January 2005 to December 2007 102 consecutive patients (mean age 76.36+/-7.54 years) with severe highly-calcified de novo lesions of carotid artery undergoing CAS were prospectively observed and randomized in two groups: group 1 (N=50) underwent standard CAS, group 2 (N=52) underwent CAS with CBA. Patients with prior ipsilateral carotid endarterectomy (CEA), betablockers therapy or arrhytmias were excluded. HD was defined as periprocedural hypotension (systolic blood pressure <90 mmHg) or bradycardia (heart rate <60 beats/min). CBA angioplasty was carried out using CB coronary device, 0.014 inch compatible, from 3 to 4 mm or CB peripheral device, 0.018 inch compatible, from 5 to 6 mm in diameter, inflated at a mean-maximum value of 8.6 atmospheres; the average number of cuts per lesion was 2.7.

RESULTS

Demographic and clinical characteristic of both groups at the basal conditions were comparable. HD occurred in 18/50 (36%) procedures in group 1, and in 3/52 (5.76%) in group 2. The difference between the two groups concerning HD incidence was statistically significant (P<0.001). There was a strong (P<0.001) association between HD and CBA and the OR=0.109 (95%CI 0.019-0.425) confirmed the protective role of CBA. No major intraprocedural complications were observed in this series. Postprocedural Doppler ultrasound scan showed one case (2%) of in-stent restenosis in group 1 representing early failure due to recoil, and only 1 (1.92%) neurological adverse event (transient ischemic attack, TIA) in group 2.

CONCLUSIONS

HD is a common occurrence after CAS, especially in patients with both long and calcified plaque. Only a tailored procedure with a correct remodelling of the plaque allows to avoid both HD and elastic recoil of the target lesion.

Subintimal angioplasty with the aid of a re-entry device for TASC C and D lesions of the SFA

AIM

The aim of this prospective study was to assess the clinical effectiveness and related midterm patency of subintimal angioplasty (SAP) in patients suffering from critical limb ischaemia (CLI) in a single tertiary care university centre. The secondary aim was to evaluate the safety and clinical effectiveness of using a re-entry device when re-canalisation by SAP was unsuccessful.

METHODS

From January 2005 to December 2007, consecutive patients suffering from CLI (Rutherford clinical categories: 4-6) were treated with SAP. All patients included in the study had occluded SFA (TASC C and D) and underwent clinical and ultrasound follow-up examinations at day 30 and at 3, 6, 9 and 12 months, and then yearly. A re-entry device (Outback, Cordis Corporation, Miami Lakes, Florida, USA in all cases) was only used when re-canalisation by simple SAP was unsuccessful, and stenting was used when residual stenosis was >30% or there was a flow-limiting dissection. Factors that could modify the outcome were analysed.

RESULTS

In this study, 145 patients were treated, with a technical success rate of 83.5% (121 of 145) for simple SAP. Stenting was performed in 43% (n=62) of successful SAP procedures. No death occurred in the perioperative period, while the 30-day mortality was 4.8% (7 of 145). The re-entry device (Outback) was used in 24 cases (16.5%). The technical success of the re-entry device was 79% (19 of 24), with a 90% success rate of stent placement at the site of re-entry. Complications occurred in 6.2% of all procedures (n=9) (three arterial perforations (2.1%), three distal embolisations (2.1%), two femoral artery pseudo-aneurysms (1.4%) and one arterio-venous fistula (0.7%)). Factors capable of independently affecting the patency were renal insufficiency (p=0.03), current smoking (p=0.01) and diabetes (p=0.04). The primary patency at 1 and 3 years was 70% and 34% and the secondary patency at 1 and 3 years was 77% and 43%, respectively. At the same time intervals, the limb-salvage rate was 88% and 49%.

CONCLUSIONS

SAP with the aid of a re-entry device for TASC C and D lesions of the SFA seems to be safe and clinically effective in patients suffering from CLI, according to the experience at our centre. Further follow-up and more data are necessary to confirm these findings.

[New evidences on spa therapy in fibromyalgia]

Spa therapy is one of the most commonly used non-pharmacological approaches for many rheumatic diseases. In Fibromyalgia Syndrome (FS) it may be useful for the chronic widespread musculoskeletal pain. Because of the unknown aetiology and the not clear understood pathogenesis, there is no standard therapy regimen for FS. Also the mechanisms of action of spa therapy are not completely known, but most probably the benefits could be derived from mechanical, physical and chemical factors. Muscle tone and pain intensity can be positively influenced by mud packs and thermal baths. The review of international data from 2000 to 2007 confirms that spa therapy should be a valid tool in the multidisciplinary approach of the Primary FS.