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Presently, many economical and technical efforts are made by pipeline industry aimed to satisfy the needs to transport gas from far away regions to the final market and to set new solutions in terms of both design criteria and new high performance materials. Due to the fact that easy Oil and Gas is largely exploited and new fields will be more and more in deeper water (it means water depths greater 305 m), that means higher pressures and temperatures and more corrosive environments, material requirements are increasing. In this situation low-alloy carbon steels tend to be structurally satisfactory, but lack in terms of corrosion resistance. On the other hand stainless steels and nickel alloys resist to corrosion environments but are lack in terms of strength or extremely costly. Clad pipes, low-alloy carbon steel with a thin layer of a corrosion-resistant alloy, is presently considered, more and more, a suitable solution to the most demanding requirements of strength, corrosion resistance and cost-effectiveness. In a cladded pipe, the (generally) unalloyed carbon steel outer pipe handles the internal and external pressure, while the high-alloy cladding provides the corrosion protection. The paper describes the pipes and fittings production starting from metallurgical clad plates. In particular the experience developed by Allied Group is described. The developed products and components represent the ideal candidate for the most severe offshore and subsea applications typical of the Oil&Gas sector. [ABSTRACT FROM AUTHOR]

Lesch-Nyhan disease (LND) is a monogenic rare neurodevelopmental disorder caused by a deficiency in hypoxanthine-guanine phosphoribosyltransferase (HPRT), the key enzyme of the purines salvage pathway. Beyond its well-documented metabolic consequences, HPRT deficiency leads to a distinctive neurobehavioral syndrome characterized by motor disabilities, cognitive deficits, and self-injurious behavior. Although various cell and animal models have been developed to investigate LND pathology, none have adequately elucidated the underlying mechanisms of its neurological alterations. Recent advances in human pluripotent stem cell research and in vitro differentiation techniques have ushered in a new era in rare neurodevelopmental disorders research. Pluripotent stem cells, with their ability to propagate indefinitely and to differentiate into virtually any cell type, offer a valuable alternative for modeling rare diseases, allowing for the detection of pathological events from the earliest stages of neuronal network development. Furthermore, the generation of patient-derived induced pluripotent stem cells using reprogramming technology provides an opportunity to develop a disease-relevant model within the context of a patient-specific genome. In this review, we examine current stem cell-based models of LND and assess their potential as optimal models for exploring key pathological molecular events during neurogenesis and for the discovering novel treatment options. We also address the limitations, challenges, and future prospects for improving the use of iPSCs in LND research., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Success of total knee replacement (TKR) depends on the prosthetic design and materials. The use of metal components is well established with the disadvantage of allergic reactions. Ceramics have been recently proposed because of high wear resistance, excellent biocompatibility, wettability, and suitable mechanical properties. This study was aimed at investigating in vitro wear resistance of Zirconia Toughened Alumina (ZTA)/Ultra-high-molecular-weight polyethylene (UHMWPE) of TKR femoral components. An in vitro protocol was designed with the application of relevant load profile, 6-degrees-of-freedom knee simulator, and 8 × 10 5 cycles on the ZTA/UHMWPE configuration under bovine calf serum. Before and after wear test, the femoral components were investigated by using the Scanning Electron Microscope (SEM) and the X-Ray Diffraction (XRD) analyses, and stylus surface roughness measurements. The proposed pre-clinical test yielded repeatable results. In particular, gravimetric results showed that, after 8 × 10 5 cycles, the mean weight loss of the polyethylene mobile components is 5.3 ± 1.1 mg. The surface roughness measurements (Ra max ) performed after the wear test showed no significant variation on the UHMWPE menisci. A slight increase of roughness has been found on the ZTA (0.02 µm before wear test, 0.28 µm after the test). SEM observations did not show significant modification of the surface morphology. Tetragonal to monoclinic phase ratio was measured by XRD before and after wear test to evaluate stability of tetragonal ZrO 2 phase. Minimal conversion of tetragonal to monoclinic phase was found from 5.4 to 8%. Although this study is a preliminary evaluation limited to in vitro tests, it provides novel pre-clinical indications about the potential of ceramic TKR femoral components.

Six cases of malignant neuroendocrine tumours (3 bronchial, 1 ileocolic) are presented; diagnostic and clinical features, functional behaviour and the results of the treatment are discussed. Early functional manifestation (diarrhoea) was observed only in the first case of ileocolic tumour: in this patient the diarrhoea disappeared after the operation but further relapse occurred at the recurrence of the pathology. In the second ileocolic tumour diarrhoea with increased levels of 5 HT appeared later on, after the operation, expressing repeated disease. In one malignant bronchial carcinoid with early spinal secondary, the typical flushes appeared only after the explosion of metastatic spread. No functional disorders were observed in one patient with metastasis localised only in the bones. On the basis of actual knowledge the authors discuss the pathogenetic hypothesis of these events. Even though these experience limited, it may remark the importance of the quantity and quality of produced hormones, of the localization of metastasis in the liver and portal district and the unconstant production of clinical symptoms. The importance of A-chromogranin and of NSE as specific markers is discussed; the studies on the chromogranin have furthermore demonstrated the possible effect of the inhibitors of protonic pump on structural, hyper-dysplastic modification of gastric mucosa and this requires further investigation.

In order to support previous in vitro studies which had stressed a possible autocrine role for Insulin-like Growth Factor 1 (IGF-1) in thyroid growth regulation, we have investigated the presence of IGF-1, as detected by means of radioimmuno assay and of immunocytochemistry, in thyrocytes from normal thyroid and from multinodular goiter. Our study revealed that IGF-1 is detectable in thyroid cells from multinodular goiter and, to a lesser extent, from normal thyroid. Both techniques used in this study demonstrated that thyrocytes are the site of accumulation of IGF-1 and that stromal cells contain lower amounts of this growth factor. The findings of the present study seem to suggest that thyrocytes could produce IGF-1 in vivo. This feature gives further support to the hypothesis that IGF-1 may regulate thyroid growth and therefore it might be involved in the pathogenesis of multinodular goiter.

This study involves a multicenter trial aimed at evaluating the comparative beneficial therapy of somatostatin and traditional symptomatic therapy in the management of acute pancreatitis. According to our final data somatostatin has not proved to be any better than traditional medical treatment. Nevertheless, in our opinion, the advantage of a single and expeditious therapy makes somatostatin administration preferable to the combined employment of several therapeutic measures usually applied in these circumstances.

On the basis of observations made in 69 patients with traumatic lesions and those caused by foreign bodies in the colon and rectum, supplemented by the data emerging from literature, some clinical and therapeutic considerations are expressed on the subject. A tactic of treatment based on the material examined and, in the present state, advisable as a possible plan of treatment for the said lesions is also proposed.