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Abstract: Nowadays, there is a growing interest towards pure hydrogen production for proton exchange membrane fuel cell applications. Methane steam reforming reaction is one of the most important industrial chemical processes for hydrogen production. This reaction is usually carried out in fixed bed reactors at 30–40 bar and at temperatures above 850 °C. In this work, a dense Pd–Ag membrane reactor packed with a Ni-based catalyst was used to carry out the methane steam reforming reaction between 400 and 500 °C and at relatively low pressure (1.0–3.0 bar) with the aim of obtaining higher methane conversion and hydrogen yield than a fixed bed reactor, operated at the same conditions. Furthermore, the Pd–Ag membrane reactor is able to produce a pure, or at least, a CO and CO2 free hydrogen stream. A 50% methane conversion was experimentally achieved in the membrane reactor at 450 °C and 3.0 bar whereas, at the same conditions, the fixed bed reactor reached a 6% methane conversion. Moreover, 70% of high-purity hydrogen on total hydrogen produced was collected with the sweep-gas in the permeate stream of the membrane reactor. From a modeling point of view, the mathematical model realized for the simulation of both the membrane and fixed bed reactors was satisfactorily validated with the experimental results obtained in this work. [ABSTRACT FROM AUTHOR]

The physical properties of in vitro iron-reconstituted and genetically engineered human heteropolymer ferritins were investigated. High-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), electron energy-loss spectroscopy (EELS), and 57 Fe Mössbauer spectroscopy were employed to ascertain (1) the microstructural, electronic, and micromagnetic properties of the nanosized iron cores, and (2) the effect of the H and L ferritin subunit ratios on these properties. Mössbauer spectroscopic signatures indicate that all iron within the core is in the high spin ferric state. Variable temperature Mössbauer spectroscopy for H-rich (H 21 /L 3 ) and L-rich (H 2 /L 22 ) ferritins reconstituted at 1000 57 Fe/protein indicates superparamagnetic behavior with blocking temperatures of 19 K and 28 K, while HAADF-STEM measurements give average core diameters of (3.7 ± 0.6) nm and (5.9 ± 1.0) nm, respectively. Most significantly, H-rich proteins reveal elongated, dumbbell, and crescent-shaped cores, while L-rich proteins present spherical cores, pointing to a correlation between core shape and protein shell composition. Assuming an attempt time for spin reversal of τ 0 = 10 -11 s, the Néel-Brown formula for spin-relaxation time predicts effective magnetic anisotropy energy densities of 6.83 × 10 4 J m -3 and 2.75 × 10 4 J m -3 for H-rich and L-rich proteins, respectively, due to differences in surface and shape contributions to magnetic anisotropy in the two heteropolymers. The observed differences in shape, size, and effective magnetic anisotropies of the derived biomineral cores are discussed in terms of the iron nucleation sites within the interior surface of the heteropolymer shells for H-rich and L-rich proteins. Overall, our results imply that site-directed nucleation and core growth within the protein cavity play a determinant role in the resulting core morphology. Our findings have relevance to iron biomineralization processes in nature and the growth of designer's magnetic nanoparticles within recombinant apoferritin nano-templates for nanotechnology., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Testicular cancer is relatively uncommon and accounts for <1% of all male tumors. However, it is the most common solid tumor in men between the ages of 20 and 34 years, and the global incidence has been steadily rising over the past several decades. Several risk factors for testicular cancer have been identified, including personal or family history of testicular cancer and cryptorchidism. Testicular germ cell tumors (GCTs) comprise 95% of malignant tumors arising in the testes and are categorized into 2 main histologic subtypes: seminoma and nonseminoma. Although nonseminoma is the more clinically aggressive tumor subtype, 5-year survival rates exceed 70% with current treatment options, even in patients with advanced or metastatic disease. Radical inguinal orchiectomy is the primary treatment for most patients with testicular GCTs. Postorchiectomy management is dictated by stage, histology, and risk classification; treatment options for nonseminoma include surveillance, systemic therapy, and nerve-sparing retroperitoneal lymph node dissection. Although rarely occurring, prognosis for patients with brain metastases remains poor, with >50% of patients dying within 1 year of diagnosis. This selection from the NCCN Guidelines for Testicular Cancer focuses on recommendations for the management of adult patients with nonseminomatous GCTs.

Exertional rhabdomyolysis is more common in sickle trait due to a predisposition to dehydration and inability to concentrate the urine. Spinning, an indoor cycling workout, has been associated with exertional rhabdomyolysis in recent reports. A consequence of rhabdomyolysis is acute kidney injury, which may be expected to be more common in patients with sickle trait. We report a case of spinning induced rhabdomyolysis in a woman with sickle trait that did not result in renal injury. "Spin rhabdo" is thought to be more severe than other causes of exertional rhabdomyolysis and is associated with higher creatine kinase levels than other causes of exertional rhabdomyolysis. Therefore, individuals with known sickle trait should visit their physician prior to participation in spin classes for the first time. We might also consider voluntary screening for sickle trait in at risk populations prior to enrolling in spin classes given that many patients are unaware of their sickle trait status., Competing Interests: No competing interests were disclosed.

Objectives: To investigate the potential association between body mass index (BMI) and clinicopathological features of clinically localized renal masses., Materials and Methods: An international, multi-institutional retrospective review of patients who underwent surgery for clinically localized renal masses between 2000 and 2010 was undertaken after an institutional review board approval. Patients were divided into 4 absolute BMI groups based on the entire cohort׳s percentiles and 4 relative BMI groups based on their respective population (American or Italian). Renal mass pathological diagnosis, renal cell carcinoma (RCC) subtype, Fuhrman grade (low and high), and clinical stage were compared among groups using Fisher׳s exact test, Kruskal-Wallis test, and the Cochran-Armitage trend test. A multivariate logistic analysis was performed to evaluate independent association between tumor and patient characteristics with tumor pathology (Fuhrman grade)., Results: A total of 1,748 patients having a median BMI of 28 (interquartile range 25-32) were evaluated. Benign masses and RCC cases had similar proportion across BMI groups (P = 0.4). The most common RCC subtype was clear cell followed by papillary carcinoma, chromophobe, and other subtypes. Their distribution was comparable across BMI groups (P = 0.7). Similarly, clinical stage distribution was comparable with the overall cohort. The distribution of Fuhrman grade in RCC, however, demonstrated an increased proportions of low grade with increasing BMI (P<0.05). This trend was maintained in subgroups according to gender, stage and age (P<0.05 in all subgroup analysis). In a multivariable model that included potential confounders (i.e., age, sex, and tumor size) higher BMI groups had lower odds of presenting a high Fuhrman grade., Conclusion: In this study, higher BMI was associated with lower grade of RCC in clinically localized renal masses. This may, in part, explain better survival rates in patients with higher BMI and may correlate with a possible link between adipose tissue and RCC biology., (Copyright © 2017 Elsevier Inc. All rights reserved.)

We completed targeted exome sequencing of the tumors of 50 patients with pTis-pT4b bladder cancer. Mutations were categorized by type, stratified against previously identified cancer loci in the Catalogue of Somatic Mutations in Cancer and The Cancer Genome Atlas databases, and evaluated in pathway analysis and comutation plots. We analyzed mutation associations with receipt of neoadjuvant chemotherapy, nodal involvement, metastatic disease development, and survival. Compared with The Cancer Genome Atlas, we found higher mutation rates in genes encoding products involved in epigenetic regulation and cell cycle regulation. Of the pathways examined, PI3K/mTOR and Cell Cycle/DNA Repair exhibited the greatest frequencies of mutation. RB1 and TP53, as well as NF1 and PIK3CA were frequently comutated. We identified no association between mutations in specific genes and key clinical outcomes of interest when corrected for multiple testing. Discovery phase analysis of the somatic mutations in 50 high-risk bladder cancer patients revealed novel mutations and mutational patterns, which may be useful for developing targeted therapy regimens or new biomarkers for patients at very high risk of disease metastasis and death., Patient Summary: In this report we found known, as well as previously unreported, genetic mutations in the tumors of patients with high-risk bladder cancer. These mutations, if validated, may serve as actionable targets for new trials., (Copyright © 2016 European Association of Urology. Published by Elsevier B.V. All rights reserved.)

Aim: to evaluate nutritional status in a representative sample of guests of residential homes for the elderly using the Mini Nutritional Assessment (MNA, Nestlè®) and compare results with data from literature., Design: cross-sectional study of prevalence using cluster sampling in two stages., Setting and Participants: the investigation focused on a sample of 420 guests of 37 facilities for the elderly, out of 2,967 residents in 89 facilities in the province of Trieste. The target population was characterised by age 65 years, with different degrees of self-sufficiency. Data were collected during 2010., Main Outcome Measures: nutritional status as defined by the MNA (good, bad, risk of malnutrition)., Results: the prevalence of malnutrition and risk of malnutrition are respectively 14.1% (CI95% 10.2-18.0) and 48.6% (CI95%43.4-53.8).The prevalence of malnutrition is higher among people residing in facilities for non self-sufficient guests: 21.4%(14.9 to 27.9) versus 9.5%(4.7 to 14.3) among people residing in facilities for self-sufficient guests. The intracluster correlation coefficients (ICC) and the relative standard error (ES) for the variables "normal nutritional status", "risk of malnutrition " and "bad nutrition" are respectively 0.19 (0.05); 0.02 (0.03); 0.05 (0.04)., Conclusion: the prevalence of malnutrition and risk of malnutrition in residential facilities for the elderly in the province of Trieste is in line with the literature. The adoption of systematic nutritional screening, under the supervision and the support of the Prevention Departments, would allow a timely adoption of preventive and targeted therapeutic interventions.

Mutations in the gene HR coding for the hairless protein are associated with atrichia with papular lesions (APL), an autosomal recessive form of alopecia universalis that is characterized by generalized scalp and body atrichia with papular lesions. We here describe a South Italian family of ancient Albanian heritage. The full phenotype with complete atrichia was expressed in 2 siblings, whereas the parents and one sister were unaffected. Direct sequencing of the gene coding for the hairless protein allowed the identification of a new mutation in exon 17. Consistent with the recessive inheritance of the disease, both the siblings were homozygous for the mutation, whereas the parents and the unaffected sister where heterozygous. A relevant discrepancy with a haplotype linkage study is reported, stressing the importance of gene sequencing in genetic diagnosis and counseling because linkage studies can be biased by recombination events.

Plasma C-reactive protein (CRP) concentration is a biomarker of systemic atherosclerosis and may also be associated with vein graft disease. It remains unclear whether CRP is also an important modulator of biological events in the vessel wall. We hypothesized that CRP influences vein graft healing by stimulating smooth muscle cells (SMCs) to undergo a phenotypic switch. Distribution of CRP was examined by immunohistochemistry in prebypass human saphenous veins (HSVs, n = 21) and failing vein grafts (n = 18, 25-4,400 days postoperatively). Quiescent HSV SMCs were stimulated with human CRP (5-50 microg/ml). SMC migration was assessed in modified Boyden chambers with platelet-derived growth factor (PDGF)-BB (5-10 ng/ml) as the chemoattractant. SMC viability and proliferation were assessed by trypan blue exclusion and reduction of Alamar Blue substrate, respectively. Expression of PDGF ligand and receptor (PDGFR) genes was examined at RNA and protein levels after 24-72 h of CRP exposure. CRP staining was present in 13 of 18 diseased vein grafts, where it localized to the deep media and adventitia, but it was minimally detectable in most prebypass veins. SMCs pretreated with CRP demonstrated a dose-dependent increase in migration to PDGF-BB (P = 0.02), which was inhibited by a PDGF-neutralizing antibody. SMCs treated with CRP showed a dose-dependent increase in PDGFRbeta expression and phosphorylation after 24-48 h. Exogenous CRP had no effect on SMC viability or proliferation. These data suggest that CRP is detectable within the wall of most diseased vein grafts, where it may exert local effects. Clinically relevant levels of CRP can stimulate SMC migration by a mechanism that may involve upregulation and activation of PDGFRbeta.

The contamination of the operating field by a number of substances including the starch used to lubricate surgical gloves is one of the causes of foreign body granuloma formation. The role of starch is particularly clearly documented in the peritoneal cavity where it may provide the basis of a well defined nosological phenomenon, "starch peritonitis", but it has also been reported in most other anatomical districts. The most logical solution to this problem is to use starch-free surgical gloves prepared using another type of lubricant without the aforesaid drawbacks. This paper analyses international clinical and experimental literature focusing on the damaging effects resulting from the introduction of starch into the peritoneal cavity.

New quaternary ammonium polymers, which in a previous work had shown relevant antibacterial properties, have been investigated as regards to their hemolytic activity (HA) in comparison with a low molecular weight commercial antibacterial agent, Steramine G (SG). All polymers exhibit negligible, or at most modest, HA at dosages and contact times at which SG is strongly hemolytic.

Hitherto the size of abdominal aortic aneurysms (AAA) has been considered the most important factor in determining the risk of rupture. For this reason most interest has been devoted to physical, echographic and tomographic analyses of the shape of AAA. However, it is known that rupture can also occur in small AAA. Other factors must be considered to have an important role in the natural history of aneurysms. The aim of this study was to characterise the mechanical stress in the wall of an AAA due to pressure in the presence of atherosclerosis, intraluminal thrombus and anatomical restraints. The Finite Elements Method (FEM) was used to determine wall stress distribution. Due to the simplicity of the AAA structure an axisymmetric model has been built. The results of the structural analysis confirms that maximum stress increases with diameter. These effects may be reduced by the presence of intraluminal thrombus, which in the models reduces maximum stress by up to 30%; however this is not the case for dissecting thrombus. On the other hand atherosclerotic plaques cause stress concentration and a significant increase in maximum wall stress. The risk of rupture can increase by about 200%. Finally the investigation shows the FEM is a versatile tool for studying the mechanics of vascular structures. It enables the influence of various parameters on wall stress to be quantified in diagnostic settings, and so could be useful for predicting the rupture of AAA, although at present such predictions are limited by data leakage and by the approximations used in the model.

A study was carried out to see if in patients with atherosclerotic lesions of the lower limbs the percentage of abdominal aneurysms is higher than in the general population. One hundred twenty five consecutive patients were studied in two different hospitals and compared with a control group. In the two groups with peripheral vascular diseases the patients had a prevalence of aneurysms of 12%, while in the control group the prevalence was of 3%. All patients were operated on successfully except two of them who are now in follow up with regular ultrasound assessment, one with an aortic aneurysm of 3.2 cm and the other with an aortic diameter of 4 cm and moderate liver failure.

Bacterial adherence to biomaterials as an element of clinical relevance is a well-known factor in the pathogenesis of sepsis. Drainages, intravascular catheters, surgical prostheses and other devices are susceptible to bacterial colonization with clinical consequences. In the last few years attention has been paid to coagulase-negative Staphylococcus (S. epidermidis), mainly to some strains able to produce a highly adhesive polysaccharide substance, called glycocalix or slime. This promotes adherence either interbacterial either between bacteria and biologic tissues or synthetic materials acting as a pathogenetic factor in sepsis being able to increase bacterial resistance to phagocytes and antibiotics. Bacterial contamination of 40 abdominal drainage tubes in patients operated in elective and in emergency surgery for various pathology has been evaluated. Sonication of the tip of the drainage was utilized in order to promote the detachment of adherent colonies and its effectiveness was compared to that of microcentrifugation. Culture of 25 drainages (62.5%) showed no bacterial contamination; 7 drainages (17.5%) have proved to be colonized by S. epidermidis, in 4 cases the isolated strains were also methicillin-resistant, 2 of which slime-producing. Out of the 7 drainages colonized by S. epidermidis, 4 were removed from patients operated in emergency: none of the isolated strains was slime-producing. Six drainages (15%) were colonized by Gram+ bacteria (S. fecalis, P-sensible cocci, rods), 1 (2.5%) by E. coli and 1 (2.5%) by P. aeruginosa, S. epidermidis appears to be the chief contaminant of abdominal drainages, especially in emergency surgery; slime production has always been observed in methicillin-resistant strains: this confirms the hypothesis that slime production is typical of specialized, virulent strains.(ABSTRACT TRUNCATED AT 250 WORDS)

Two cases of aorto-bisiliac aneurysms in monocorial twins in their sixties were observed. We report experimental and clinical data from the literature about genetic involvement in the formation of aneurysms, especially when associated with other risk factors. In addition to the genetic factors in the twins we studied, we also found other risk factors, such as hypertension and smoking, which took a long time to affect the patients before the aneurysms were detected.

On the basis of a recent case of fundic gastric heterotopia in the gallbladder, the principal, possible embryogenetic hypotheses of the malformation are described and discussed. The possibility that acid secretion of the gastric glands contained in the ectopic fundic mucosa determined part of the symptomatological and clinical picture accompanying signs of lithiasic cholecystopathy is also evaluated.

Recordings of blood velocity profiles and their behavior in the time domain in some peripheral human vessels (carotid arteries and limb vessels) are reported. Measurements have been obtained with a pulsed ultrasonic instrument based on the analysis of the cross-correlation function of blood-diffused echoes. The alterations of blood velocity profiles and of the velocity in the time domain, induced by known stenosis, have been studied in vitro as a function of the distance between stenosis and measuring point, and the position of the sample volume along the diameter. These studies may be useful for a better comprehension of blood velocity measurements made with ultrasound equipment for clinical noninvasive diagnostic purposes.

We have investigated the influence of changes of perfusion pressure and local peripheral resistance on blood flow velocity waveform and profile in normal human peripheral arteries. Blood flow velocity and profile were recorded from the distal end of the left brachial artery in ten normal subjects by means of an ultrasonic device. The records were obtained in basal conditions and after blood pressure in the brachial artery and local peripheral vascular resistance were changed, separately or together, by progressive inflation of two arm cuffs, one encircling the proximal half of the left arm and the other the middle part of the left forearm. Both blood flow velocity waveform and profile were shown to be markedly modified by changes in perfusion pressure and local peripheral vascular resistance. Reduction of perfusion pressure decreased both forward and reverse peak velocities, but had the largest effect upon reverse velocity. The upslope and the downslope of the forward velocity wave were left unchanged. Increase in local peripheral vascular resistance markedly augmented reverse peak velocity, whether perfusion pressure was normal or reduced. Increased resistance only slightly influenced peak forward velocity.

A case of biliopancreatic pathology studied with traditional (the old algorithm) and the latest (new algorithm) diagnostic techniques is examined. A comparative analysis reveals the second to be simpler, less expensive and less dangerous to the patient. The hope is expressed that doctors will become better informed of the diagnostic criteria to employ for the purpose of cost reduction.

The "quality" of poly(glycolic acid) as an absorbable suture material was investigated in comparison with catgut. Tissue reactions to poly(glycolic acid) and plain catgut were examined histomorphologically at different time intervals after implantation in rats, and compared. Four mechanical properties were also examined as relevant quality factors: elastic stiffness, tensile strength, toughness, and percent elongation at rupture of the suture material per se (unknotted). The variation of these properties in poly(glycolic acid) implants was followed since their insertion in the tissues. Histological behavior and mechanical properties appear to be more closely correlated in the case of poly(glycolic acid) than in the case of catgut, as a consequence of a greater regularity of tissue reaction towards the synthetic material. Both tissue reaction and tensile properties variation are independent of size in the case of the braided poly(glycolic acid) sutures examined. Elastic stiffness and tensile strength decrease steadily in time; toughness and ultimate elongation display an increase up to a maximum within one day since implantation, and then decrease.

Experiments were performed on 19 anaesthetized open-chest dog instrumented with polyethylene catheters inserted: into the aorta, in pulmonary artery and in left atrium and with an electromagnetic flow-transducer placed around the ascending aorta in order to record : systemic arterial and pulmonary pressures, mean left auricular pressure and phasic aortic flow. Heart rate, stroke volume, total systemic and pulmonary resistance, cardiac work were moreover calculated. Each dog was given intravenously by slow infusione : Dopamine (micrograms 5--10--20/kg/min/ 5 min), Isoproterenol (microgram 0.125--0.25--0.5/kg/min/5 min) and Norepinephrine (microgram 0.25--0.5--1 /kg/min/5 min). Results obtained on systemic hemodynamics agree with those reported by many other investigators. On pulmonary circulation : Isoproterenol, at the tested doses, elicited vasodilator effects, Norepinephrine increased total pulmonary resistance but not pulmonary vascular resistance, while Dopamine did not modify or slightly reduced vascular pulmonary tone.

Tissue reactions to polyglycol acid and plain catgut threads were compared. The second part of the paper deals with changes in the mechanical properties of the polymer. Their reduction after insertion in tissues was proportionally equal for threads of different sizes. This finding is explicable histologically, since it can be shown that cell and humoral attack of the single filaments is homogenous throughout the entire cross-section of the thread.

A rare case of persistent primitive sciatic artery with a small aneurysm in its proximal part is reported. The occlusion of this artery caused extensive lower limb ischemia which called for amputation. The diagnostic difficulties are stressed out.

Latero-lateral femoro-femoral arteriovenous fistulae (AVFs) were surgically created in mongrel dogs. After 7-9 months during which the dogs were trained on a treadmill, devices suitable for recording arterial pressure and aortic and coronary flow were chronically implanted. Haemodynamic parameters of the dogs were controlled either at rest or after effort, keeping AVFs open or manually closed. The results, when statistically processed, showed that haemodynamic changes induced by occlusion of AVFs at rest and under effort are similar from a qualitative point of view, but considerably more marked after muscular exercise. Under effort the shunt index calculated rose to a higher extent than cardiac output. The decrease in heart rate after AVFs occlusion was significantly correlated with flow in the fistulae. However, the Nicoladoni-Branham phenomenon ought to be used for indirect evaluation of the shunt flow.

An anatomical study shows that the vascular junctions are always very well rounded in accordance with the direction of the blood flow. When performing an anastomosis, the further one departs from this configuration, which we can define as perfect, the more flow disturbances are likely to arise. This may jeopardize the satisfactory outcome of surgery.

A physiopathological interpretation is offered of the possibilities given by recent selective or portally regulated reduction of pressure in achieving a balance between reduction of pressure and diversion. Classic demonstrations, in fact, prove effective in the prevention of haemorrhage due to rupture of oesophageal varices. On the other hand, by over-diversion of the portal flow from the liver, they may cause a further deterioration in liver performance and more imposing the greater the flow of portal blood through the liver preoperatively. Procedures aimed at de-tension of the portal system, particularly the gastro-oesophageal segment, and at ensuring an intrahepatic venous flow sufficient to obviate steal syndrome damage, are described. Some of these procedures are still at the experimental stage. The techniques involved are explained, along with the underlying principles achieved by or prospected for each of them.