Development, characterization and sterilisation of Nanocellulose-alginate-(hyaluronic acid)- bioinks and 3D bioprinted scaffolds for tissue engineering.

3D-bioprinting is an emerging technology of high potential in tissue engineering (TE), since it shows effective control over scaffold fabrication and cell distribution. Biopolymers such as alginate (Alg), nanofibrillated cellulose (NC) and hyaluronic acid (HA) offer excellent characteristics for use as bioinks due to their excellent biocompatibility and rheological properties. Cell incorporation into the bioink requires sterilisation assurance, and autoclave, ß-radiation and γ-radiation are widely used sterilisation techniques in biomedicine; however, their use in 3D-bioprinting for bioinks sterilisation is still in their early stages. In this study, different sterilisation procedures were applied on NC-Alg and NC-Alg-HA bioinks and their effect on several parameters was evaluated. Results demonstrated that NC-Alg and NC-Alg-HA bioinks suffered relevant rheological and physicochemical modifications after sterilisation; yet, it can be concluded that the short cycle autoclave is the best option to sterilise both NC-Alg based cell-free bioinks, and that the incorporation of HA to the NC-Alg bioink improves its characteristics. Additionally, 3D scaffolds were bioprinted and specifically characterized as well as the D1 mesenchymal stromal cells (D1-MSCs) embedded for cell viability analysis. Notably, the addition of HA demonstrates better scaffold properties, together with higher biocompatibility and cell viability in comparison with the NC-Alg scaffolds. Thus, the use of MSCs containing NC-Alg based scaffolds may become a feasible tissue engineering approach for regenerative medicine.

Type 1 Diabetes Mellitus reversal via implantation of magnetically purified microencapsulated pseudoislets.

Microencapsulation of pancreatic islets for the treatment of Type I Diabetes Mellitus (T1DM) generates a high quantity of empty microcapsules, resulting in high therapeutic graft volumes that can enhance the host's immune response. We report a 3D printed microfluidic magnetic sorting device for microcapsules purification with the objective to reduce the number of empty microcapsules prior transplantation. In this study, INS1E pseudoislets were microencapsulated within alginate (A) and alginate-poly-L-lysine-alginate (APA) microcapsules and purified through the microfluidic device. APA microcapsules demonstrated higher mechanical integrity and stability than A microcapsules, showing better pseudoislets viability and biological function. Importantly, we obtained a reduction of the graft volume of 77.5% for A microcapsules and 78.6% for APA microcapsules. After subcutaneous implantation of induced diabetic Wistar rats with magnetically purified APA microencapsulated pseudoislets, blood glucose levels were restored into normoglycemia (<200 mg/dL) for almost 17 weeks. In conclusion, our described microfluidic magnetic sorting device represents a great alternative approach for the graft volume reduction of microencapsulated pseudoislets and its application in T1DM disease.

Silk flow-diverter stent for the treatment of complex intracranial aneurysms: A one-year follow-up multicenter study.

Background Flow-diverter stents have been successfully used in the treatment of complex aneurysms with limited therapeutic alternatives. We report our experience using the Silk flow diverter (SFD; Balt Extrusion, Montmorency, France) for the treatment of complex aneurysms in four Argentine centers. Methods We conducted a retrospective review of 246 consecutive patients who were treated with the SFD at four Argentine centers between January 2009 and January 2017. The patient and aneurysm characteristics, as well as the details of the procedure, were analyzed. The angiographic and clinical findings were recorded during and immediately after the procedure and at 12-month follow-up. Results Angiography follow-up at 12 months was possible in 235 patients (95.5%) with 282 aneurysms. A total of 265 aneurysms (93.9%) presented with complete occlusion of the aneurysmal sac (class 1) and 17 aneurysms (6.1%) presented with partial occlusion (class 2). The 12-month clinical follow-up showed 11 patients with major events (seven, scale 2; five, scale 3; and two, scale 4). The morbidity and mortality rates were 4.2% (11/289) and 2.1% (5/289), respectively. Conclusions The treatment of aneurysms with the SFD was associated with a low rate of complications and a high percentage of aneurysmal occlusion. These findings suggest that SFD is an effective and safe alternative in the endovascular treatment of complex aneurysms.

Concordance between brain 18F-FDG PET and cerebrospinal fluid biomarkers in diagnosing Alzheimer's disease. / Concordancia entre la PET cerebral con 18F-FDG y los biomarcadores en líquido cefalorraquídeo en el diagnóstico de enfermedad de Alzheimer.

OBJECTIVES: Cortical posterior hypometabolism on PET imaging with 18F-FDG (FDG-PET), and altered levels of Aß1-42 peptide, total Tau (tTau) and phosphorylated Tau (pTau) proteins in cerebrospinal fluid (CSF) are established diagnostic biomarkers in Alzheimer's disease (AD). An evaluation has been made of the concordance and relationship between the results of FDG-PET and CSF biomarkers in symptomatic patients with suspected AD. MATERIAL AND METHODS: A retrospective review was carried out on 120 patients with cognitive impairment referred to our Cognitive Neurology Unit, and who were evaluated by brain FDG-PET and a lumbar puncture for CSF biomarkers. In order to calculate their Kappa coefficient of concordance, the result of the FDG-PET and the set of the three CSF biomarkers in each patient was classified as normal, inconclusive, or AD-compatible. The relationship between the results of both methods was further assessed using logistic regression analysis, including the Aß1-42, tTau and pTau levels as quantitative predictors, and the FDG-PET result as the dependent variable. RESULTS: The weighted Kappa coefficient between FDG-PET and CSF biomarkers was 0.46 (95% CI: 0.35-0.57). Logistic regression analysis showed that the Aß1-42 and tTau values together were capable of discriminating an FDG-PET result metabolically suggestive of AD from one non-suggestive of AD, with a 91% sensitivity and 93% specificity at the cut-off line Aß1-42=44+1.3×tTau. CONCLUSIONS: The level of concordance between FDG-PET and CSF biomarkers was moderate, indicating their complementary value in diagnosing AD. The Aß1-42 and tTau levels in CSF help to predict the patient FDG-PET cortical metabolic status.

Metal exposure influences the melanin and carotenoid-based colorations in great tits.

Metals are naturally found in the environment but are also emitted through anthropogenic activities, raising some concerns about the potential deleterious effects of these elements on wildlife. The potential effects of metals on bird coloration have been the focus of several recent studies since animal colored-signals often reflect the physiology of their bearers and are thus used by animals to assess the quality of another individual as a mate or competitor. These studies have shown that the melanin pigmentation seems to be positively associated and the carotenoid-based coloration negatively associated with metal exposure in wild birds. Although these studies have been very useful to show the associations between metal exposure and coloration, only few of them have actually quantified the levels of metal exposure at the individual level; always focusing on one or two of them. Here, we measured the concentrations of eight metals in great tits' feathers and then assessed how these levels of metals were associated with the carotenoid and melanin-based colorations. We found that the melanin pigmentation was positively associated with the copper concentration and negatively correlated with the chromium concentration in feathers. In addition, we have shown that the carotenoid-based coloration was negatively associated with the feather's mercury concentration. This study is the first one to identify some metals that might affect positively and negatively the deposition of melanin and carotenoid into the plumage of wild birds.

Darkness during early postnatal development is required for normal circadian patterns in the adult rat.

Early light experience influences the brain during development. Perinatal light exposure has an important effect on the development of the circadian system, although the role of quantity versus quality of light in this process is still unclear. We tested the development of the circadian rhythm of locomotor activity under constant bright light from the day of weaning, of six groups of rats raised under different light conditions during suckling. Results indicated that when rats received daily darkness during suckling (rats reared under constant darkness or light-dark cycles with dim or bright light) became arrhythmic when exposed to continuous bright light after weaning. However, those rats reared in the absence of darkness (constant dim or bright light, or alternating dim and bright light) developed a circadian rhythm, which was stronger and had a shorter period depending on the quantity of light received during suckling. Vasointestinal polypeptide immunoreactivity in the suprachiasmatic nucleus (SCN) was higher in those rats with weaker rhythms. However, no apparent differences among these groups were found in the melanopsin-expressing retinal ganglion cells, which provide the SCN with light input in the photoentrainment process. When bright light was shifted to dim light in three of the groups on day 57 after weaning, all of them generated a circadian rhythm with a longer period in those rats previously arrhythmic. Our results indicate the importance of the amount of light received at the early stages of life in the development of the circadian system and suggest that darkness is needed for the normal development of circadian behaviour.

[Palpitations in stress situations]. / Palpitaciones en situación de estrés.

Wolff-Parkinson-White (WPW) syndrome, a congenital heart abnormality, is the most common of the pre-excitation syndromes. The prevalence of WPW syndrome ranges from 0.1 to 3 cases per 1000 people. A large majority (80%) of patients with WPW syndrome develop supraventricular tachycardia, between 15% and 30% atrial fibrillation, and atrial flutter 5%. The clinical presentation can vary from vertigo, palpitations, breathlessness, chest tightness, to sudden death in rare cases. We report the case of a patient presenting with WPW syndrome after a stressful work situation.

Social interaction and sex differences influence rat temperature circadian rhythm under LD cycles and constant light.

Circadian rhythms produce an efficient organization of animal behaviour over the 24h day. In some species, social cues have been found to have a role as synchronizers of these rhythms. Here, the influence of social interaction on rat circadian behaviour was investigated, addressing the question of whether cohabitation would produce a delay in the appearance of arrhythmicity under constant light conditions. To this end, the circadian rhythms of male and female rat body temperature were studied for 10days under light-dark conditions, followed by 33days under constant bright light. Half of the animals were maintained in individual cages, whilst the others were maintained in larger cages in groups of three rats of the same sex. Results showed that individual circadian rhythms under 24hour light-dark (LD) cycles were more stable and with higher amplitude in grouped than in isolated animals, and higher in males than in females. During the first days under constant light (LL), the stability of the rhythm was also higher in males than in females, but there were no differences according to the group. Moreover, we did not find significant differences in the time of circadian rhythm loss under LL, since high individual variability was found for this variable. On the other hand, female rats living in isolation showed a delayed acrophase in the circadian rhythm under LD conditions compared with those living in groups. These results suggest that cohabitation increases the internal coherence of circadian behaviour, and could be interpreted as indicating that living in isolation may induce a level of stress that disturbs manifestation of the circadian rhythm, especially in females, which are also more reactive than males to external signals.

Variability and effects of bronchial colonisation in patients with moderate COPD.

Sputum and lung function were periodically assessed in stable moderate chronic obstructive pulmonary disease (COPD) outpatients to determine relationships between bronchial colonisation and inflammation. Relationships between potentially pathogenic microorganism (PPM) typology, bronchial inflammation (neutrophilia, tumour necrosis factor-alpha, interleukin (IL)-1beta, IL-6, IL-8, IL-10 and IL-12) and post-bronchodilator decline in forced expiratory volume in 1 s (FEV(1)) were analysed. PPMs periodically showing the same molecular profile using pulse field gel electrophoresis were considered long-term persistent. Bronchial colonisation was observed in 56 out of 79 follow-up examinations (70.9%) and was mainly due to Haemophilus influenzae, Pseudomonas aeruginosa and enterobacteria (n = 47). These PPMs were all related to sputum neutrophilia (p< or =0.05, Chi-squared test), and H. influenzae was related to higher levels of IL-1beta (p = 0.005) and IL-12 (p = 0.01), with a dose-response relationship (Spearman's correlation coefficient of 0.38 for IL-1beta (p = 0.001), and of 0.32 for IL-12 (p = 0.006)). Haemophilus parainfluenzae was not associated with an identifiable inflammatory response. Long-term persistence of the same strain was observed in 12 examinations (21.4%), mainly due to P. aeruginosa or enterobacteria. A neutrophilic bronchial inflammatory response was associated with a statistically significant decline in FEV(1) during follow-up (OR 2.67, 95% CI 1.07-6.62). A load-related relationship to bronchial inflammation in moderate COPD was observed for colonisation by H. influenzae, but not for colonisation by H. parainfluenzae.

Low-dose theophylline enhances the anti-inflammatory effects of steroids during exacerbations of COPD.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is characterised by an abnormal inflammatory response mainly to cigarette smoke that flares up during exacerbations of the disease (ECOPD). Reduced activity of histone deacetylases (HDAC) contributes to enhanced inflammation in stable COPD. It was hypothesised that HDAC activity is further reduced during ECOPD and that theophylline, an HDAC activator, potentiates the anti-inflammatory effect of steroids in these patients. A study was performed to investigate HDAC activity during ECOPD and the effects of theophylline on the anti-inflammatory effects of steroids in a randomised single-blind controlled study. METHODS: 35 patients hospitalised with ECOPD and treated according to international guidelines (including systemic steroids) were randomised to receive or not to receive low-dose oral theophylline (100 mg twice daily). Before treatment and 3 months after discharge, HDAC and nuclear factor-kappaB (NF-kappaB) activity in sputum macrophages, the concentration of nitric oxide in exhaled air (eNO) and total antioxidant status (TAS), tumour necrosis factor alpha (TNFalpha), interleukin (IL)-6 and IL8 levels in sputum supernatants were measured. RESULTS: Patients receiving standard therapy showed decreased NF-kappaB activity, eNO concentration and sputum levels of TNFalpha, IL6 and IL8, as well as increased TAS during recovery of ECOPD, but HDAC activity did not change. The addition of low-dose theophylline increased HDAC activity and further reduced IL8 and TNFalpha concentrations. CONCLUSIONS: During ECOPD, low-dose theophylline increases HDAC activity and improves the anti-inflammatory effects of steroids. TRIAL REGISTRATION NUMBER: NCT00671151.

The management of constipation in palliative care: clinical practice recommendations.

Constipation is one of the most common problems in patients receiving palliative care and can cause extreme suffering and discomfort. The aims of this study are to raise awareness of constipation in palliative care, provide clear, practical guidance on management and encourage further research in the area. A pan-European working group of physicians and nurses with significant experience in the management of constipation in palliative care met to evaluate the published evidence and produce these clinical practice recommendations. Four potentially relevant publications were identified, highlighting a lack of clear, practical guidance on the assessment, diagnosis and management of constipation in palliative care patients. Given the limited data available, our recommendations are based on expert clinical opinion, relevant research findings from other settings and best practice from the countries represented. Palliative care patients are at a high risk of constipation, and while general principles of prevention should be followed, pharmacological treatment is often necessary. The combination of a softener and stimulant laxative is generally recommended, and the choice of laxatives should be made on an individual basis. The current evidence base is poor and further research is required on many aspects of the assessment, diagnosis and management of constipation in palliative care.

Neonatal pulmonary tuberculosis evolving to a destroyed lung.

Tuberculosis (TB) in the newborn is infrequent, difficult to diagnose and often devastating. Congenital TB is rare, with most neonates and young infants becoming infected after birth. The incidence of neonatal TB might increase in industrialised countries as a result of immigration from countries with higher TB incidence among women of childbearing age. We report two cases of post-natally acquired pulmonary TB in newborns who developed marked lung destruction, a complication of TB which has seldom been described in the first month of life. A high index of clinical suspicion is required when evaluating pregnant women at risk for TB and their ill children, as early identification and treatment can prevent the devastating consequences of TB.

Ultrasonography of the pancreas. 1. Conventional imaging.

Ultrasound imaging has made significant advances in recent years and plays an important role in the detection, characterization and staging of pancreatic diseases. Conventional ultrasonography (US) is a noninvasive imaging modality, which continues to be the first diagnostic step in the evaluation of the pancreas. Over its various decades of application, US have detected pancreatic pathology of great diversity. This article reviews the wide utility of US and the many examinations techniques, such as filling the stomach with water, changing the patient's position or suspending inspiration or expiration, allowing us to visualize all portions of the pancreas in a high percentage of patients.

Intracellular cytokine profile of T lymphocytes in patients with chronic obstructive pulmonary disease.

Chronic obstructive pulmonary disease (COPD) is characterized by an excessive inflammatory response to inhaled particles, mainly tobacco smoking. T lymphocytes are important regulatory cells that secrete several cytokines and participate actively in this inflammatory response. According to the pattern of cytokines secreted, the immune response is classified as cytotoxic or type 1 [interferon (IFN)-gamma-, interleukin (IL)-2-dependent] and humoral or type 2 (IL-4-, IL-5-, IL-10- and IL-13-dependent). This paper sought to compare the intracellular profile of cytokine expression determined by flow cytometry in T lymphocytes harvested from bronchoalveolar lavage (BAL) and peripheral blood in patients with COPD, smokers with normal lung function and never smokers. We found that BAL T lymphocytes from COPD patients had a higher percentage of positive stained cells for most of the cytokines analysed when compared to never smokers or smokers with normal lung function. Differences reached statistical significance for IL-4, IL-10 and IL-13, particularly in CD8(+) T cells. Furthermore, the expression of most of these cytokines was related inversely to the degree of airflow obstruction present suggesting local activation and/or selective homing of T lymphocytes to the lungs in COPD patients. These observations were not reproduced in circulating T lymphocytes. These results suggest that BAL T lymphocytes in patients with COPD produce more cytokines than in controls and tend to show a type 2 pattern of intracellular cytokine expression, particularly a Tc-2 profile. This is related inversely to the degree of airflow obstruction present.

Motor activity rhythms of forced desynchronized rats subjected to restricted feeding.

Although light is the strongest zeitgeber for the circadian pacemaker, other stimuli can also produce entrainment. In the rat, periodic restricted feeding (RF) is a weak stimulus that may act as a zeitgeber. We tested the effect of RF on the motor activity rhythms of rats subjected to forced dissociation. In this situation two components, supposed to be related with the ventrolateral and dorsomedial areas of the suprachiasmatic nucleus, are detected in their motor activity. One component is entrained to the external light-dark cycle (Light Dependent Component, LDC) and thus has the same period, while the other has a period longer than 24 h (Non-Light Dependent Component, NLDC). This experiment examined whether RF can act on one or both of these two rhythms. Rats were maintained under the light-dark cycles of 22 h (T22) or 23 h (T23) for 44 days with food available for four hours per day. Afterwards the rats received food ad libitum, to test the effect of the previous RF condition. Results show that RF modifies the manifestation of the two initial rhythms, being this effect stronger under T23 than under T22. However RF does not affect the NLDC period. The results reveal that the animal can manifest simultaneously several rhythmic patterns.

CT features of abdominal plasma cell neoplasms.

The aim of this study was to describe the CT features of abdominal plasma cell neoplasms. We reviewed CT imaging findings in 11 patients (seven men, four women; mean age 62 years) with plasma cell neoplasms and abdominal involvement. Helical CT of the entire abdomen and pelvis was performed following intravenous administration of contrast material. Images were analyzed in consensus by two radiologists. Diagnoses were made from biopsy, surgery and/or clinical follow-up findings. Multiple myeloma was found in seven patients and extramedullary plasmacytoma in four patients. All patients with multiple myeloma had multifocal disease with involvement of perirenal space (4/7), retroperitoneal and pelvic lymph nodes (3/7), peritoneum (3/7), liver (2/7), subcutaneous tissues (2/7) and kidney (1/7). In three of the four patients with extramedullary plasmacytoma, a single site was involved, namely stomach, vagina and retroperitoneum. In the fourth patient, a double site of abdominal involvement was observed with rectal and jejunal masses. Plasma cell neoplasm should be considered in the differential diagnosis of single or multiple enhancing masses in the abdomen or pelvis. Abdominal plasma cell neoplasms were most frequently seen as well-defined enhancing masses (10/11).