Hydrogels have been widely used in many fields including biomedicine and water treatment. Significant achievements have been made in these fields due to the extraordinary properties of hydrogels, such as facile processability and tissue similarity. However, based on the in-depth study of the microstructures of hydrogels, as a result of the enhancement of biomedical requirements in drug delivery, cell encapsulation, cartilage regeneration, and other aspects, it is challenge for conventional homogeneous hydrogels to simultaneously meet different needs. Fortunately, heterogeneous multilayer hydrogels have emerged and become an important branch of hydrogels research. In this review, their main preparation processes and mechanisms as well as their composites from different resources and methods, are introduced. Moreover, the more recent achievements and potential applications are also highlighted, and their future development prospects are clarified and briefly discussed. Hydrogel is a kind of hydrophilic material with a three-dimensional crosslinked network structure, which is infiltrated with water . It can The research and design of polymer-based hydrogels are mainly based on the overall consideration of their properties, and the resultant hydrogels are usually homogeneous materials . HoweverIn this review, we summarize the recent progress of the multilayer hydrogels and their composites. Particularly, we review the preparation processes and mechanisms of multilayer hydrogels and their innovative applications in different fields, especially in the biomedical field, including drug delivery, cell carrier or encapsulation, wound dressings (coatings), and bone repair. Finally, we provide a brief perspective on the future development of multilayer hydrogels, hoping to provide some theoretical guidance on broadening hydrogels’ application.Many different preparation methods for multilayer hydrogels have been developed in recent years according to different raw materials, crosslinking structures , and potential applications. These methods can be generally divided into two pathways according to the formation direction of hydrogel layers: from the inside to the outside and from the outside to the inside.More recently, the preparation of multilayer hydrogels from inside to outside has been widely studied, and its main preparation technology is as follows: First, suitable materials are selected to prepare inner gel cores  with special shapes according to application requirements. Then, a first gel layer is formed on the gel core by different crosslinking or coagulation methods through pretreating the gel core with subsequent soaking in certain solutions. Finally, the fabrication process is repeated several times to generate multilayer hydrogels with the desired number of layers. The volume of multilayer hydrogels continues to grow until the preparation process of the multilayer structure is completed by gradually wrapping or covering the gel cores with gel layers.Compared with the pathway from inside to outside, the preparation of multilayer hydrogels from outside to inside has been studied much less, although this form appeared earlier. The main preparation process is as follows: First, suitable raw materials are selected to prepare the hydrogel shells, which can wrap the solutions corresponding to the following gel layers. Second, a first gel layer is formed on the inner wall of the shell by different coagulation or crosslinking methods. Finally, the above fabrication process is repeated several times to generate multilayer hydrogels with the desired number of layers. The total volume of multilayer hydrogels prepared from outside to inside cannot increase after the formation of the shells. All the gelation processes occur inside the shells and move from the shell to the center of the gel with a gradual layer-by-layer (LBL) formation.Detailed preparation methods are commonly used for the above two pathways, which can be roughly divided into the lLBL method and non-LBL method, as follows.At present, LBL assembly is the most widely used method for the preparation of multilayer hydrogels from different polymers such as polysaccharides. LBL assembly can be used to prepare multilayer structures by different driving forces or crosslinking types. Different LBL assembly methods are suitable for the preparation of multilayer hydrogels with different performances and application requirements. In the following discussion, several commonly used LBL methods are analyzed from the aspects of preparation principle, advantages, and application prospects.Chemical crosslinking is a common method of preparing homogenous hydrogels via the use of crosslinking agents. Interestingly, multilayer hydrogels with arbitrary shapes, including onion-like, tubular, and star-like, can be readily prepared using the chemical crosslinking method a–d throuFor chemically crosslinked multilayer hydrogels by the LBL process, reasonable and rapid crosslinking is essential for successful preparation. The formation and growth of each gel layer are related to the diffusion of the crosslinker. The inter-layer space canbe adjusted by changing the crosslinking degree of gel layers. Moreover, the chemically cross-linked chitosan multilayer hydrogels have a unique sub-layer structure . The chi2+ was prepared by diffusing Ca2+ into the sodium alginate solution to crosslink alginate molecule chains. Second, the above gel core was immersed in the sodium alginate solution for a given time to prepare a hydrogel layer, which was further cured in the Ca2+ solution. Finally, alginate-based multilayer hydrogels with the desired layers could be prepared by repeating the above-mentioned process. In addition, carboxymethyl cellulose and other polyanions can be crosslinked by Ca2+, Al3+, and other polyvalent inorganic cations to form hydrogels . I. I2, whi process a. Finall− to the CS solution , and bone repair. The achievements and practical applications of multilayer hydrogels have mainly focused on the biomedical field. Moreover, multilayer hydrogels have also been used in other fields, such as tuning ice nucleation and propagation, dye adsorptions, and forward-osmosis (FO) desalination, due to their unique structure, modifiable properties, and higher surface area.Natural polymer-based multilayer hydrogels usually have excellent biocompatibility, and multilayer hydrogels in the forms of microspheres or capsules can effectively encapsulate and release drugs and bioactive substances. Inspired by biologic lipid bilayers , the devCM) ..72]. The E. coli c,d. MoreTürkŏglu et al. fabricated a wheat germ oil (WGO)-loaded multilayer hydrogel dressing by cross-linking sodium alginate (SA) with poly(ethylene glycol) diglycidyl ether (PEGDGE) on textile nonwovens . This muIn addition to dressings, coatings from organic and inorganic materials can also be considered an excellent strategy to prevent bacterial adhesion, bacterial infection, and subsequent biofilm formation . MultilaShi’s group fabricated a chitosan/silver nanoparticle (AgNP) multilayer hydrogel coating via the combination of in situ synthesis of AgNPs on a pre-deposited chitosan multilayer hydrogel . The coaIn addition to the large number of achievements and applications in the biomedical field, multilayer hydrogels can also be used in other fields. Three selected different application fields are introduced in the following.The tuning of both ice nucleation and ice propagation via a simple anti-icing coating method is an important research topic, and was first investigated by Guo et al. using multilayer hydrogels . Figure To solve the bottleneck of the lack of suitable draw agents in the development of FO desalination, Zeng et al. developed a multilayer temperature-responsive hydrogel on the basis of poly(N-isopropylacrylamide-co-sodium acrylate) (P(NIPAAm-co-SA)) . The mulAs a result of the continuous improvement in people’s living standards and the deepening of research in various fields, hydrogels have been widely developed and studied. Although many homogenous hydrogels with different excellent properties have been developed and improved continuously in recent decades, significant room remains for further development of hydrogels, because it is a challenge for these homogeneous hydrogels to simultaneously meet different needs due to the restrictions of their structure. Fortunately, novel multilayer hydrogels from different resources have emerged as required and become a new branch of hydrogels. Multilayer hydrogels have attracted significant attention and been studied and utilized in various fields due to their unique structure and excellent properties, as outlined above. Most preparation techniques (roughly classified as LBL and non-LBL) and related mechanisms of different multilayer hydrogels were cited and systematically discussed in this review. These impressive works will not only have a significant impact on the construction of multilayer hydrogels in the future, but also shed light on industrial processing for exploiting multilayer hydrogels in daily life.However, in general, recent research and applications of multilayer hydrogels remain insufficient and lack maturity. Moreover, commercial products have not yet emerged because the existing methods for the production of multilayer hydrogels are relatively complex and difficult to apply in industrial settings. In addition, it is a challenge to implement the main biomedical applications, particularly in the clinical phase, because caution is needed in the evaluation of biomedical materials. Thus, further effort is required to develop novel methods and accelerate the evaluation of the long-term biocompatibility of multilayer hydrogels as implants. As a result of the continuous development of science and technology, prolific creativity, and effective cooperation, we believe that the preparation process of multilayer hydrogels will be optimized, and their properties will be continuously improved. Therefore, the issues relating to industrialization and biomedical applications of multilayer hydrogels may be solved based on the in-depth study of abundant resources, modifiable layers, and advanced technologies, and multilayer hydrogels can be eventually applied to every aspect of our lives.


Determining the diagnostic value of available biomarkers in predicting rhabdomyolysis-induced acute kidney injury (AKI) is a priority. This study aimed to review the current evidence about the value of lactate dehydrogenase (LDH) in this regard.In this narrative review, the papers in PubMed, Embase, and web of science were studied. The keywords prognosis, prognoses, prognostic, LDH, rhabdomyolysis, emergency patients, and acute kidney failure or AKI had been selected from MeSH medical dictionary. Related papers written in English and published from November 2007 to December 2020 were selected. Finally, 14 articles were accepted for analysis. Among the selected articles, four were randomized clinical trials, seven were cross-sectional, and three were case-control studies. The results of the present review showed that abuse of illegal drugs is the most common cause of rhabdomyolysis. AKI is the most serious complication of rhabdomyolysis reported in the studies. These studies have shown a three-fold increase in AKI following drug-induced rhabdomyolysis. The review of the included articles shows that high LDH can predicts AKI, especially in critical and emergency situations such as rhabdomyolysis where there is a risk of death if diagnosed late. These studies show that LDH increases in the presence of renal failure and tissue damage. Serum LDH is an appropriate and cost-effective prognostic indicator that can be used for risk classification of patients at risk for rhabdomyolysis-induced AKI.  Rhabdomyolysis accounts for 5 to 25% of all acute kidney injuries (AKIs) . The oveConsidering the importance of early diagnosis of at-risk patients in emergency department, determining the diagnostic value of available biomarkers in predicting rhabdomyolysis induced AKI is a priority , 6.Muscle damage leads to membrane disruption, extracellular fluid leakage, and increased serum level of creatine phosphokinase (CK) and lactate dehydrogenase (LDH) enzymes -10. LDH Various studies have evaluated the level of this enzyme at the time of kidney damage and have shown that in most cases, very high concentrations of LDH have been observed in the serum of patients with rhabdomyolysis, which indicates that it can be useful in predicting renal failure , 14. BasStudy design In this narrative review, the keywords prognosis, prognose, prognostic, lactate dehydrogenase (LDH), rhabdomyolysis, emergency patients, and acute kidney injury or acute renal failure had been selected from MeSH medical dictionary. Related papers written in English and published from November 2007 to December 2020 were searched in PubMed, Embase, and web of science. Original researches with available full text, which had evaluated the value of LDH in detection of at-risk patients for rhabdomyolysis-induced AKI were selected. Case reports, letters to the editors, and review papers were omitted. Search process and assessment of papersThere was no restriction on duration of intervention, type of participants, and place of study. The steps for selecting the papers were as follows: First the initial search was performed by two researchers separately and the duplicate papers were removed, then with the aim of eliminating unrelated articles, the abstract and the title of each article were reviewed, potentially related papers meeting the inclusion criteria were identified. The full texts of the papers were reviewed by two authors and discussed until consensus was reached regarding their suitability.After compiling a list of study titles and abstracts in the databases, the Strobe standard checklist was used to determine the quality of the studies. The Strobe checklist consists of 22 different sections that assess various aspects of methodology including sampling methods, statistical analysis, confounding factor adjustment, measurement of variables, validity and reliability of the tools used, and the objectives of the study. Data extractionThe specific characteristics of each study were extracted by the researchers using a standard form. Two researchers examined the data independently, based on the inclusion criteria. In case of disagreement between the researchers, help was sought from a third researcher.The differences in findings were resolved using the method of benchmarking the overall conclusions of the articles and in this study, it was organized. Findings on rhabdomyolysis, AKI, and their association with lactate dehydrogenase were derived.231 titles were extracted. In the initial screening stage, the title and type of articles were reviewed and finally 140 articles were excluded. Then, the full text of the articles was studied and 50 articles were excluded due to differences in purpose. Of the remaining 41 articles, 27 articles were excluded due to duplication of content and exclusion criteria, and finally, 14 articles were accepted for analysis . The speAmong the selected articles, four were randomized clinical trials, seven were cross-sectional, and three were case-control studies. The studies, either specifically or generally, examined serum level condition and prognostic ability of LDH in predicting rhabdomyolysis-induced AKI. Amongst the fourteen articles, eight  reported a high serum level and prognostic value of LDH in kidney disease. The target groups were often 30-60 year-old individuals and a case-control study was conducted on rats. The results of the present review showed that abuse of illegal drugs is the most common cause of rhabdomyolysis. AKI is the most serious complication of rhabdomyolysis reported in the studies -18. ThesThe studies showed that the serum level of LDH was high in patients with renal impairment and the concentration of this enzyme significantly increased in patients with rhabdomyolysis. Studies have also shown that LDH can be useful in early diagnosis of acute renal failure in children. The exact process or processes of the development of rhabdomyolysis-induced AKI are not yet clear. A number of proposed processes include mechanical damage to renal tubules caused by myoglobin deposition, and direct effect of the toxic property of free iron on renal tubules and volume depletion , 20, 21.The researchers reported that LDH levels significantly increased in acute renal failure, especially in conditions caused by rhabdomyolysis -18. UndeIn the analysis of the reviewed studies, it can be concluded that serum LDH is an appropriate and cost-effective prognostic indicator that can be used for risk classification of patients with acute renal failure due to rhabdomyolysis. Given the importance of rhabdomyolysis-induced acute renal failure, it is recommended that serum LDH level be measured at the time of admission to the emergency department and in the event of symptoms such as coma, convulsions, and elevated body temperature during the hours after hospitalization in order to promptly start treatment if rhabdomyolysis is proven.Further understanding of the value of LDH in predicting rhabdomyolysis-induced AKI could be the subject of more extensive research, as present studies in this area are limited to a small number of randomized controlled trials, case studies, and retrospective studies. We need to conduct more multi-centered studies to confirm the findings of the present review and deeply explore the mechanism.The results showed that the level of LDH was high in patients with renal impairment and this enzyme significantly increased in patients with rhabdomyolysis. Studies have also shown that LDH can be useful in early diagnosis of acute renal failure in children.


The COVID-19 pandemic has had disproportionately severe impacts on Indigenous peoples in the United States compared to non-Indigenous populations. In addition to the threat of viral infection, COVID-19 poses increased risk for psychosocial stress that may widen already existing physical, mental, and behavioral health inequities experienced by Indigenous communities. In recognition of the impact of COVID-19 related psychosocial stressors on our tribal community partners, the Johns Hopkins Center for American Indian Health Great Lakes Hub began sending holistic wellness boxes to our community partners in 11 tribal communities in the Midwestern United States and Canada in summer of 2020. Designed specifically to draw on culturally relevant sources of strength and resilience, these boxes contained a variety of items to support mental, emotional, cultural, and physical wellbeing. Feedback from recipients suggest that these wellness boxes provided a unique form of COVID-19 relief. Additional Johns Hopkins Center for American Indian Health offices have begun to adapt wellness boxes for the cultural context of their regions. This case study describes the conceptualization, creation, and contents of these wellness boxes and orients this intervention within a reflection on foundations of community-based participatory research, holistic relief, and drawing on cultural strengths in responding to COVID-19. American Indian and Alaska Native peoples, hereafter referred to as Indigenous peoples, have long experienced poorer mental and physical health outcomes than non-Indigenous Americans, including high rates of suicide, type 2 diabetes, cardiovascular disease, liver disease, and a variety of infectious diseases . From thCOVID-19 in Indigenous communities also elevates psychosocial stressors and exacerbates health inequities. Psychosocial stress is an etiological contributor to behavioral, mental, and physical health problems . Prior rThe Johns Hopkins Center for American Indian Health (CAIH) partners with Indigenous communities across North America to promote health, health leadership, and self-sufficiency. Founded in 1991, the CAIH works collaboratively with tribal partners in the areas of infectious disease prevention and treatment, behavioral health promotion, and training of Indigenous health professionals. In August of 2019, the authorship team of the current manuscript joined the CAIH as the CAIH Great Lakes Hub (GLH). The GLH research team includes over 100 tribal members across 11 Indigenous communities in the upper Midwestern United States and Canada. Our team is engaged in numerous health-related studies and intervention projects, primarily on reservation/reserve lands. All GLH studies and projects are co-led by university-based investigators and Community Research Councils comprised of tribal community members. Many of our team members have worked in partnership for nearly 20 years. All of our projects are rooted in community-based participatory research (CBPR), an approach to research that recognizes communities as necessary and equal partners in the creation of knowledge and in its application . The appAs the COVID-19 pandemic progressed, our research team temporarily paused projects, regrouped, and adapted to web and phone-based modalities. Tribally-based team members persisted in their work even as communities closed key operations and schools, caregiving roles were amplified, and financial, health, and race-related stressors peaked. Yet, the strains of social isolation and accumulating pressures were palpable among our team, particularly as the pandemic contributed to disconnection from seasonal cultural activities, ceremonies, and social gatherings—all known protective factors for health in Indigenous communities .In March of 2020, the CAIH moved quickly to dedicate resources to respond to the COVID-19 pandemic. Deep seated relationships, existing team structures, and momentum of our CBPR team enabled us to shift efforts rapidly to address the pandemic. One response effort by the GLH was the creation of holistic wellness boxes, which is the focus of the current manuscript. In April of 2020, both U.S. states within which our research team operates were granted disaster declarations by the federal government . In recoAs the pandemic persisted and our team continued regular video calls, community-based research team members voiced an increasing need for a more holistic COVID-19 response approach that would address not only physical health, but also cultural, spiritual, emotional, and mental health. Years of collaborative work on issues of Indigenous health equity allowed our team to draw on a shared understanding of culture as a source of strength and healing that can strengthen efforts to address modern day health inequities—including the disproportionate impact of COVID-19 on Indigenous peoples. Thus, to meet the need for culturally relevant psychosocial support, we designed and distributed holistic wellness boxes and aimed for box contents to be: 1) evidence-based; 2) responsive to the needs voiced by community partners; 3) culturally relevant and; 4) logistically feasible. We also gave attention to sourcing box supplies from local and Indigenous retailers as much as possible.Traditional Indigenous foods are highly nutritious. They’re healing, spiritual and comforting. They are home to our people. When we provide traditional foods to our people, we are healing as well.  a foundation of CBPR; 2) a holistic approach to relief and; 3) fostering resilience and wellbeing by drawing on cultural strengths.Building a base and alliances. Our research team includes over 100 individuals from 11 tribal nations, many of whom are members of tribal government or who represent tribal agencies or clinics. Leadership. Each partner community is represented in our CBPR efforts by a Community Research Council, the members of whom share leadership with university based researchers. Ideas and vision. As already discussed, many years of partnership in working toward Indigenous health equity has enabled our team to reach a unified understanding of historically rooted social determinants as the underlying cause of modern day health inequities and of the capacity of culture to promote health. Infrastructure for advocacy. Through networks and relationships forged over decades with individuals, organizations, and tribal governments, the research of our team has led to the implementation of a number of evidence-based, culturally relevant interventions in partnership with tribal communities. During COVID-19, established patterns of communication and collaboration with community partners allowed us to understand what needs were most urgent, quickly adapt to changing priorities, tailor the wellness boxes to address contextually specific stressors, and draw on community specific strengths.Fundamental to our COVID-19 response approach and the creation of the wellness boxes was communication and engagement with community partners built on a foundation of many years of partnership and collaboration. As mentioned above, all of the work of our team operates within a framework of CBPR. CBPR involves equal partnership between communities and academic institutions in the generation and application of knowledge . DefininThe COVID-19 pandemic is disproportionately affecting the physical and psychosocial health of Indigenous communities . DisasteA foundational element of CBPR is building on the strengths that already exist within communities . SimilarIndigenous communities hold within themselves reservoirs of cultural knowledge, teachings, and practices that have the capacity to protect and promote holistic health. The boxes provided by the CAIH GLH are one example—rooted in cultural strengths and scientific evidence—of an intervention designed and driven by community feedback to holistically address wellbeing in the time of COVID-19.Due to the need to distribute boxes quickly, there was no empirical evaluation of the impact of the holistic boxes on health outcomes. Developing a pre/post evaluation would have considerably delayed distribution of the boxes. Thus, the impact of the wellness boxes on COVID-19 related physical and psychosocial health outcomes cannot be fully known. Future similar interventions could investigate the empirical impact of similar, culturally and scientifically grounded care packages on physical and psychosocial health. There are numerous innovative and Indigenous approaches to evaluation including storytelling, sharing circles, photovoice, and open-ended interviews, which may afford appropriate venues through which to explore the impact of these forms of gifting on holistic health . DespiteFor centuries, the Indigenous populations of North America have experienced disproportionate impacts from infectious diseases . The emeCOVID-19 has taken a toll not only on physical health, but also on mental, spiritual, emotional, and cultural health. A holistic response approach that strengthens existing sources of strength, resilience, and healing may be a useful addition to interventions striving to address physical and psychosocial wellbeing during COVID-19. In Indigenous communities, drawing on cultural strengths, knowledge, and teachings can be a powerful tool for protecting and promoting health . The hol


Purpose of Review: The purpose of this review is to summarize recent literature regarding the latest design modifications and biomechanical evolutions of reverse total shoulder arthroplasty and their impact on postoperative outcomes. Recent findings: Over the past decade, worldwide implantation rates of reverse total shoulder arthroplasty have drastically increased for various shoulder pathologies. While Paul Grammont’s design principles first published in 1985 for reverse total shoulder arthroplasty remained unchanged, several adjustments were made to address postoperative clinical and biomechanical challenges such as implant glenoid loosening, scapular notching, or limited range of motion in order to maximize functional outcomes and increase the longevity of reverse total shoulder arthroplasty. However, the adequate and stable fixation of prosthetic components can be challenging, especially in massive osteoarthritis with concomitant bone loss. To overcome such issues, surgical navigation and patient-specific instruments may be a viable tool to improve accurate prosthetic component positioning. Nevertheless, larger clinical series on the accuracy and possible complications of this novel technique are still missing. The idea of reverse total shoulder arthroplasty (RTSA) was first introduced in 1974 by Charles Neer and has considerably progressed ever since ,3. The gIn 1985, Paul Grammont introduced the novel “ball-and-socket” design, which was based on four key principles: (1) shifting the center of rotation medially to decrease the mechanical torque at the glenoid component, thus avoiding glenoid loosening; 2) lowering the humerus to tension the deltoid muscle, which increases muscle fiber recruitment of the anterior and posterior deltoid in order to compensate a deficient rotator cuff; 3) a fixed center of rotation distalized and medialized to the glenoid joint line, leading to an inherently stable implant; (4) a large glenosphere increasing the range of motion through a semi-constrained implant feature . In 1987 lowering a fixed Although RTSA has been performed for more than 30 years, varying outcomes have been published, reporting complication rates ranging from 0 to 69% ,14,15,16From a biomechanical point of view, modern modifications of implant designs and component’ configurations are still based on the four key principles of Paul Grammont’s design . CompareBy distalization and medialization of the center of rotation, RTSA changes the biomechanics of the glenohumeral joint in a way that maximizes deltoid efficiency, thus enabling the patient’s deltoid muscle force by permission of a higher preload of the muscle fibers and a reduction in the deltoid muscle in relation to the joint’s center of rotation ,21. ThisAfter the failure of a directly cemented fixation of the two-thirds of a sphere-shaped glenosphere to the glenoid bone stock, the original design of the glenoid baseplate, according to Paul Grammont, was fixed using a central press-fit, hydroxy-apatite-coated cylindric peg and two additional peripheral divergent screws . NowadayAnatomically, a pear-shaped or ovoid glenoid baseplate may improve primary implant fixation and bone ingrowth by an increased contact area of the implant to the glenoid . In a biRegarding different anchoring possibilities for glenoid baseplate fixation, no scientific evidence on superior or inferior stability exists between screwed, keeled, single-pegged, or double-pegged glenoids ,31. HoweFor the ultimate fixation of the glenoid baseplate, cortical non-locking screws with compression, locking screws, and compression screws can be used . HoweverTo overcome complications of glenoid baseplate loosening in the early designs of RTSA, the center of rotation was consequently medialized to reduce the mechanical torque at the glenoid component ,36. As aTo overcome this issue, a lateralization of the glenoid side relative to the medialized center of rotation was expected to reduce postoperative scapular notching . In a biLateralization of the glenosphere by using a bony augmentation or a metal-augmented baseplate represents a novel option to overcome complications such as scapular notching and compromised external rotation ,47. The Recent studies have pointed out the importance of the superior–inferior orientation of glenoid erosion. Humeral head migration in rotator cuff arthropathy might influence the pattern of glenoid wear ,58. In tThe original glenosphere, according to Paul Grammont, was designed corresponding to two-thirds of a sphere and thereby led to a medialization of the center of rotation . GlenospTo decrease polyethylene wear and concomitant osteolysis, several studies focused on the inversion of mechanical bearings in RTSA, resulting in a glenosphere made of polyethylene and an articulating humeral liner consisting of metal or ceramic ,65,66. PTo improve the range of motion after RTSA, larger diameter glenospheres became more popular over the last years. In a cadaver study, a glenosphere with a diameter of 42 mm and a lateralized spacer of 7 mm or 10 mm showed the best range of motion for internal and external rotation. However, active range of motion is dependent on muscle strength and can therefore not be evaluated in a cadaver study . Mollon Lateralization of 6 mm to 8 mm was shown to positively improve active axial glenohumeral rotation and impingement-free range of motion ,53,56,75Besides an inferior overhang, the glenosphere can be implanted with an inferior tilt, leading to further distalization and medialization of the center of rotation with a possible benefit for patients suffering from a rotator cuff tear arthropathy . In a viUntil now, positioning of the glenoid component remains a crucial step in RTSA, since it affects the long-term survival and functional outcomes of prosthesis ,83. InacIn his first design, Paul Grammont proposed a long and straight cemented stem . HoweverAn important point in humeral component implantation was the decision on the use of bone cement to ensure a sufficient fixation. In recent years, uncemented humeral fixation has become more successful and has allowed the development of bone preserving short-stem and stemless humeral prosthesis ,90,91. NLimitations in internal and external rotation remain a challenge in modern RTSA . RotatioThe original polyethylene humeral inlay from Paul Grammont was designed at a neck-shaft-angle (NSA) of 155° with a depth of 8 mm . Since tThe NSA plays a crucial role in implant stability and has a major influence on clinical outcomes. The NSA is measured by a line along the central intramedullary axis of the humeral shaft and a tangent passing through the anatomic neck-head junction ,104. AccIn the case of prosthetic joint instability, the use of a more constrained or retentive inlay is suggested ,107. WhiIn order to implant the polyethylene cup within the metaphyseal component of the humeral shaft, reaming of the metaphyseal area is mandatory. However, this might cause excessive bone loss, ultimately leading to resorption of the tuberosities. To overcome this issue, another design change was made to RTSA, leading to novel onlay polyethylene liners being placed just above the metaphysis at the level of the humeral head osteotomy. This onlay design results in a lateralization of the humerus by mechanical shifting of the humeral stem from the glenosphere, which might lead to an overstuffing of the joint, eventually causing impaired range of motion or failure of RTSA due to excessive shear forces and mechanical torque ,112,113.Since adequate and stable fixation of prosthetic components can be challenging, especially in massive osteoarthritis and concomitant bone loss, surgical navigation and patient-specific instrument (PSI) techniques were first introduced in the mid-to-late 2000s and later adapted in 2014 by Ianotti et al. . PSI andSeveral software tools are available using standard preoperative computed tomography scans of the shoulder to define the optimal positioning of the implants ,120. CurUltimately, patient-specific drill guides became available for the surgical procedure . Until nOne of the most common failures following RTSA is the malpositioning of the glenoid component, which is associated with increased humeral instability, leading to inferior outcomes and ultimately to component loosening ,83,126.A new approach to improve RTSA is the use of mixed reality-guided implantation. Augmented reality, a technique that allows the superimposing of a digital image on top of the visual field, may be a key tool for the future . In 2018Despite satisfying clinical results ,125, theRTSA has revolutionized the management of many shoulder pathologies over the past years. Constant changes in prosthetic designs were made to overcome complications such as implant loosening, scapular notching, or limited range of motion. By the medialization of the glenohumeral center of rotation, as originally suggested by Paul Grammont in his first design of RTSA, deltoid abduction effectiveness could be increased by up to 30% compared to native anatomy. On the other hand, lateralization of the center of rotation using an autologous bone graft or a metal-augmented baseplate is associated with lower rates of scapular notching and improved shoulder rotation capacity. The use of novel PSI techniques and computer navigation may be a viable tool with which to improve accurate component positioning, leading to a patient-oriented, tailor-made RTSA.


At times, leaves must operate under light limiting conditions while at other instances , the same leaves must modulate light capture to avoid photoinhibition and achieve a uniform internal light gradient. The light-harvesting capacity and the photosynthetic performance of a given leaf are both determined by the organization and the properties of its structural elements, with some of these having evolved as adaptations to stressful environments. In this respect, the present review focuses on the optical roles of particular leaf structural elements (the light capture module) while integrating their involvement in other important functional modules. Superficial leaf tissues (epidermis including cuticle) and structures  play a crucial role against light interception. The epidermis, together with the cuticle, behaves as a reflector, as a selective UV filter and, in some cases, each epidermal cell acts as a lens focusing light to the interior. Non glandular trichomes reflect a considerable part of the solar radiation and absorb mainly in the UV spectral band. Mesophyll photosynthetic tissues and biominerals are involved in the efficient propagation of light within the mesophyll. Bundle sheath extensions and sclereids transfer light to internal layers of the mesophyll, particularly important in thick and compact leaves or in leaves with a flutter habit. All of the aforementioned structural elements have been typically optimized during evolution for multiple functions, thus offering adaptive advantages in challenging environments. Hence, each particular leaf design incorporates suitable optical traits advantageously and cost-effectively with the other fundamental functions of the leaf.Leaves have evolved to effectively harvest light, and, in parallel, to balance photosynthetic CO Each moLeaf functions must be harmonized with all environmental variables, including the light regime, in order for photosynthesis to proceed under favorable circumstances. At times, leaves must operate under light limiting conditions, meaning that they must maximize light capture, while at other instances the same leaves may function under very strong light and must modulate light capture to avoid photo-inhibition . These c2 acquisition and minimal water losses. In contrast, the very low energy supply in the forest understory requires suitable optical elements for effective maximal light harvesting.The strong variability of the structural elements comprising the light capture module  has led In this review we examine the following: (1) the optical role of specific leaf structural elements within the frame of the light capture module and (2) the potential involvement of these elements in the function of the other three modules, as well as their probable combination with other leaf structural traits.The leaf surface has a key role in protection against multiple stress factors such as water loss, insect or pathogen attack, excess PAR and UV radiation. and overheating. Superficial leaf tissues (epidermis including cuticle) and structures  play a crucial role against light interception  Figure a–e. As tThe epidermis is usually one compact layer of chloroplast-free cells without intercellular spaces. The outer walls of epidermal cells are overlaid by the structurally complex layer of the cuticle, which consists mainly of polymerized lipid materials such as cutin or cutan and intra- and epi-cuticular waxes ,10,11. TIt should be pointed out that the UV-screening function of epidermal phenolic compounds is only one of the multifaceted roles of these metabolites. Photo-protection itself is also provided by the radical scavenging ability of phenolic compounds , while iThe epicuticular waxes and the cuticle covering the surface of all aerial plant parts reflect both UV and PAR, but not necessarily to the same extent, with UV (and blue) reflectance being greater in some cases  due to RWhile UV reflectance appears to occur from the cuticle–air interface, PAR reflectance appears largely from the mesophyll as a result of diffused internal reflectance ,39. As sSilicon (Si) is a key beneficial structural element in grasses as it enhances the leaf strength and mitigates various stress effects. Si is deposited in the form of phytoliths in the epidermis of the leaves, including epidermal long cells, bulliform cells, guard cells, and prickle hairs. Although there is no direct evidence, there are some indications that these structural elements can reflect the incident UV radiation, thereby protecting the underlying tissues from photo-inhibitory damage ,41,42,43Anthurium and Begonia. Understory plants grow on the forest floor beneath a dense canopy where the light regime is typically diffuse and photon flux density (PFD) values are very low, even to attain gross photosynthetic rates higher than the light compensation point. Direct light can penetrate to the understory only in the form of sunflecks. Aside from these intense rays of direct light, the photosynthetic performance of understory plants relies mainly on low PFD diffuse light. These epidermal cells behave as convex lenses concentrating collimated light (such as direct sunlight) in the mesophyll area , native in South Africa, display some of the most peculiar structural and functional adaptations in the plant kingdom to tolerate adverse conditions  in their growth environment. The major part of the biomass of these plants, including much of their photosynthetic tissue, is located underground [Lithops protects the plant from herbivory by small mammals through camouflage. Light enrichment through the epidermal windows is expected to benefit carbon assimilation. However, covering these windows did not seem to reduce net assimilation rates in three succulent species [Lithops plants have sufficient biochemical flexibility to respond to variable light conditions within the same leaf (extreme high light intensity in the above ground region and moderate or low intensity in the below ground) [Succulent species of the genus erground . The experground ,54. Thus species . The pre species ). This m species , as the  species . At the  species . Moreove ground) ,59.Trichomes (or hairs) are unicellular or multi-cellular superficial appendages of an epidermal origin, classified either as glandular or non-glandular . GlandulRecretohalophytes are halophytes able to secrete salt out of the leaf interior directly onto the leaf surface, due to the occurrence of superficial salt glands . The excSpecies of the major Southern Hemisphere family, Proteaceae, are characterized by sclerophyllous leaves with very thick cuticles and multiseriate sclerified pseudohypodermis beneath the epidermis and hypodermis a. Based Leaf tissues, both photosynthetic and non-photosynthetic, as well as other structural components, such as phytominerals and idioblasts, participate in the modulation of the internal light environment. Light propagation should be such as to allow for deep light penetration and a uniform light environment, i.e., form a smooth internal light gradient along the mesophyll depth. This is particularly important under conditions of strong collimated light, because such light conditions may favour steep light gradients inside the mesophyll. On the other hand, a strong incident light is a prerequisite for an optimal photosynthetic rate which, in turn, requires a smooth light gradient inside the mesophyll in order to allow all of the photosynthetic cells to photosynthesize at a quite high rate . The lig2 from the stomata, usually located at the abaxial epidermis in bifacial leaves, to the upper palisade layer where the larger proportion of photosynthesis takes place [The optical properties of the photosynthetic cells affect the light interception efficiency of the leaves. The most prominent example is the structural design of bifacial leaves. In these leaves, the mesophyll is usually differentiated into two distinct regions, the upper palisade and the lower spongy parenchyma layer. The palisade cells are elongated, with their axis mostly parallel to the direction of the incident collimated light. This arrangement allows these cells to operate as optical fibres, facilitating light channelling deeper into the leaf ,80,88,89es place .3-lime) cystoliths are common cellular solid calcium-carbon inclusions in plants (CaCIs) [3 deposition occurs mainly in four members of the order Urticales, i.e., Cannabaceae, Moraceae, Ulmaceae, and Urticaceae, as an encrustation on cell walls or in an unusual deposit called cystolith located in enlarged idioblasts, the lithocysts [3 cystoliths are directly involved in light scattering, reducing the steep light gradient within mesophyll and thus enabling a more efficient use of the incident PAR [Lithops aucampiae leaves may scatter light within the below-ground region of the leaves, thus enriching the lower tissues with photons [As representatives of the biomineralization process, calcium oxalate (CaOx) crystals and calcium carbonate (CaCO (CaCIs) ,97,98. Cthocysts   and common aspen (Populus tremula). The leaves of many grass species are also strongly heterobaric. All of these species must benefit from this leaf design, despite the fact that leaves are not always very thick. So, there it seems possible that, in such cases, another property of heterobaric construction is advantageous. As most of these leaves move continuously, oscillate, or tremble due to the wind, the angle of incidence of solar radiation changes accordingly. The BSE network in this case may contribute to the homogenization of light harvesting both spatially  and temporally (smoothing the intense variations due to oscillations of the lead lamina), thus enhancing uninterrupted photosynthesis.Heterobaric leaves are also common in complex canopy species (trees and shrubs) of which some species bear flexible long petioles such as in grapevine . These cells extend more or less perpendicularly from each side of a bundle sheath into the middle of the mesophyll, with their long axis parallel to the epidermis i. FusoidAs noted in the introductory section, the evolution of different leaf designs is driven by the maximization of economic efficiency, achieved by a profitable combination of the most suitable optical properties in the structural elements of the light capture module with the functions of the other three, i.e., the water–nutrient flow, gas exchange, and defense–protection module. Under this prism, single structural elements are typically optimized to participate in multiple functions served by different modules . Thus, mSuperficial structural elements are manifold interfaces between the plant and the biotic and abiotic environment. The epidermis is a key structural element, involved not only in the function of the light capture module, but also in the function of the other three modules. This tissue, together with the highly hydrophobic lipid-rich cuticle, protects the leaf against uncontrolled water losses and regulates gas exchange through the stomata (water–nutrient flow and gas exchange modules) ,122. It An important link for these multiple functions of the epidermis and the non-glandular trichomes is the occurrence of the phenolic compounds, i.e., multifunctional compounds that behave not only as UV filters and antioxidants (protection module), but also act as pro-oxidant, antifeeding agents, or toxic factors (defense module) ,31). As Sclereid idioblasts and lignified BSEs often occur in xeromorphic leaves, possibly playing a role in preventing tissue damage under drought or mechanical stress , hours , months , and years (gap formation in a canopy or forest) . Plants The presence of light conducting elements  is more intense in sun compared with shade leaves. This significant difference is compatible with the light transferring function of these structural elements, as sun leaves are also thicker and light-deficient deep cell layers may occur despite having access to full sunlight compared with shade leaves ,129). PrPhillyrea latifolia [The indumentum of mature leaves of many plants is considered as a fixed and static structural element because usually the cells of the trichomes are dead at maturity, hence there is no chance for further structural or biochemical changes . Howeveratifolia . Moreoveatifolia ,157.The evidence from the great variability, both in terms of adaptation  and acclimatization , suggests that light capture has been optimized to increase leaf photosynthetic efficiency, but also to protect leaves from high intensities of PAR and UV radiation. The optical properties of virtually all structural elements of leaves are integrated, with many able to undergo considerable modulation so as to be efficient not only in terms of the light capture module, but also functionally incorporated with other functional modules of the leaf entity. This tremendously sophisticated design proves the critical importance of the structural and functional optimization of the leaf optical properties in plant survival and productivity under fluctuating environments.The optical role of several structural elements (components of the light capture module) is still under debate. For example, the role of non-photosynthesizing tissues in complex optical phenomena (detour effect and sieve effect) is not definite, especially in regards to the geometry of light (collimated or diffuse). The answer to these questions is an important challenge, both because these phenomena are universal, and because it will be useful for plant improvement programs and for planning elements of modern crop systems such as artificial lighting in plant factories, etc. Secondly, understanding the reasons for the notable variety in leaf designs (in terms of adaptation) and plasticity (in terms of acclimatization) on photosynthesis requires long-term research and new analytical, simulating, and modeling tools that will allow us to reconstruct this complexity and elucidate the role of each component and as a whole. A third challenge will come from the necessity to scale-up this cell-, tissue-, and leaf-level structure to function model at larger levels of organization , as well as to further integrate functional anatomy with photosynthesis and other functions of the leaf (the other three modules). This integration will allow us to predict how plants with specific characteristics behave under particular environments.


The second is the quality of oocytes, including the correctness of meiotic divisions, among other factors. Notably, the increased rate of sub- and infertility, aneuploidy, miscarriages, and birth defects are associated with advanced maternal age, especially in women above 35 years of age. This postponement is also relevant for human evolution; decades ago, the female aging-related fertility drop was not as important as it is today because women were having their children at a younger age. Spindle assembly is crucial for chromosome segregation during each cell division and oocyte maturation, making it an important event for euploidy. Consequently, aberrations in this segregation process, especially during the first meiotic division in human eggs, can lead to implantation failure or spontaneous abortion. Today, human reproductive medicine is also facing a high prevalence of aneuploidy, even in young females. However, the shift in the reproductive phase of humans and the strong increase in errors make the problem much more dramatic at later stages of the female reproductive phase. Aneuploidy in human eggs could be the result of the non-disjunction of entire chromosomes or sister chromatids during oocyte meiosis, but partial or segmental aneuploidies are also relevant. In this review, we intend to describe the relevance of the spindle apparatus during oocyte maturation for proper chromosome segregation in the context of maternal aging and the female reproductive lifespan.Human female fertility and reproductive lifespan decrease significantly with age, resulting in an extended post-reproductive period. The central dogma in human female reproduction contains two important aspects. One is the pool of oocytes in the human ovary (the ovarian reserve; approximately 10 Following great improvement in education and lifestyle, maternal age has significantly increased in developed countries compared with the last few decades, and in parallel, the age at which women have their first child has also increased . One of Multiple potential mechanisms have been suggested to be responsible for the age-associated decline in oocyte quality, such as mitochondrial dysfunction, epigenetic alterations, DNA damage, and chronic exposure to oxidative stress, which are not discussed in this review. Another crucial factor for the aging-related decline of oocytes is the meiotic spindle apparatus, which has piqued researchers’ interest. During mammalian oocyte maturation, proper spindle assembly ensures even distribution and segregation of chromosomes during meiosis . HerewitIn this review, the significance of proper meiotic spindle assembly of the mammalian oocyte in advanced maternal age and its importance for chromosome segregation is presented. Additionally, this review covers specific key pathways, checkpoints of meiotic spindle formation, and the causes of spindle abnormalities. Finally, we describe the aspects related to euploidy relevant for in vitro fertilization (IVF) clinics.Proper spindle formation in oocytes ensures error-free meiosis. It involves a sequence of events, such as microtubule nucleation, organization in a bipolar fashion, and chromosome alignment at the equator of the spindle, to enable correct segregation . SimilarDifferent models of chromosome assembly at the meiotic spindle equator have been proposed in the past. During mitosis, the “search and capture” model relies on the capture and stabilization of centrosome-nucleated microtubules by the kinetochores of both sister chromatids of each chromosome . HoweverAsymmetric cytokinesis is an attribute of both meiotic divisions in oocytes and results in the formation of the large oocyte and the small polar bodies. It is well-established that spindle relocation from the center to the cortex of the oocyte is guided by the cytoplasmic actin microfilaments ,22. DefiInterestingly, microtubule organizing centers (MTOCs) in oocytes usually do not possess centrioles; however, they contain pericentriolar matrix (PCM) proteins, which are typical for mitotic centrosomes, such as pericentrin, γ-tubulin, NEDD1, and nuclear mitotic apparatus protein (NuMA) . In miceIn summary, the RAN-GTP gradient is crucial for microtubule nucleation, especially in human eggs, and the importance of MTOCs and their interplay with other proteins cannot be neglected. How advanced maternal age influences these processes will be discussed in the following section.Perhaps the most well-documented effect of the aging-related phenotype in the oocyte is chromosome segregation failure, in other words, the increasing prevalence of aneuploidy. This hallmark of aging in oocytes frequently occurs during the first meiotic division. Aneuploidy is known to be the cause of miscarriage and mental retardation ,47 and cAs mentioned in the previous sections, the SAC is a signaling system composed of different proteins, such as monopolar spindle 1 (MPS1) , membersAlong with the relevance of the SAC proteins, age-associated chromosomal segregation failures might be due to weakened cohesion between sister chromatids during meiosis I ,70,71,72In summary, aneuploidy in human eggs is caused by the nondisjunction of entire chromosomes or sister chromatids during oocyte meiosis, but partial or segmental aneuploidies were also described , resultiThe process of chromosome segregation is extremely sensitive, even to minor changes in the timing or biochemistry of spindle formation. Confocal microscopy studies have shown that human oocytes from women over 40 years of age who reproduce naturally have a high incidence of meiotic spindle aberrations, such as altered tubulin localization and the displacement of the chromosome from the metaphase plate of meiosis II . AnalogoDuring the IVF procedure, the meiotic spindle of oocytes is very susceptible to disruption due to temperature imbalances. This issue has been addressed in many studies investigating the effects of temperature alterations on ultrastructural and molecular characteristics of human oocytes ,95,96,97Findings related to the incidence of aneuploidy in oocytes that were matured in vitro compared with those matured in vivo are contradictory. On one hand, a study by Cooper et al.  providedThe undisturbed functioning of the meiotic spindle during the first and second meiotic divisions of the oocyte is critical for producing viable oocytes and significantly determines the future development of the embryo, the successful establishment of pregnancy, and the ultimate success—healthy offspring. Abnormalities in the meiotic spindle in oocytes lead to disorders of chromosome segregation and, consequently, aneuploidy of the embryo , which uWell-known phenotypes associated with aneuploidy in humans are trisomies of chromosome 21 (Down syndrome), chromosome 18 (Edwards syndrome), and chromosome 13 (Patau syndrome) . In the Unfortunately, there are limited options to select euploid human oocytes for in vitro fertilization under clinical conditions, as techniques that allow the detailed visualization of the spindle cannot be performed because of their invasive nature. However, the use of polarized light microscopy (commonly available in IVF laboratories) is not satisfactory, as it provides insufficient information on spindle morphology. Another type of aneuploidy is a consequence of mitotic errors that occur during early embryonic cleavages. In some cases, aneuploid embryos contain both euploid and aneuploid blastomeres, but these blastocysts are not selected for embryo transfer . FurtherSeveral studies provide evidence that it is worth performing preimplantation genetic testing to detect aneuploidy in embryos generated from women of advanced age, and using this procedure, the live birth rate can be increased ,133,134.On the basis of the above-mentioned studies, one can conclude that the generation of aneuploid gametes due to factors such as aging and the environment can have fatal consequences and, therefore, a significant clinical relevance for female patients. Especially in oocytes, the process of spindle formation and the involved proteins and pathways are very sensitive to the earlier mentioned factors, which can give rise to aneuploid embryos. Reasonable testing for aneuploidy should be performed if possible.In conclusion, the proper arrangement of the meiotic spindle is essential for the euploidy of human oocytes. The challenging mechanisms, particularly of meiosis I spindle formation, are, however, progressively decompensated in individuals of advanced maternal age. A growing number of studies have shown that the process of spindle formation in oocytes is a critical determinant of oocyte developmental ability and the survival of the early embryo. This has sparked the interest of researchers studying molecular reproductive medicine to better understand, diagnose, and potentially prevent age-related spindle defects and meiotic nondisjunction. Advances and improvements in assisted reproductive technologies and biotechnologies over the past thirty years have made it possible to create animal models to study the interplay of individual pathways and processes in oocytes during meiosis. All in all, our review aimed to stimulate new research ideas on this interesting topic that could help in the development of new animal models.


Microfluidics is a growing research field that requires a working knowledge of physics, biology, chemistry, and engineering. It has the potential to influence subject areas from chemical synthesis and biological analysis to optics and information technology. However, the impact of microfluidic systems will only become apparent when everyone has easy access to use it. At the current stage, however, detailed information relating to experimental design, troubleshooting, data analysis, etc. for the microfluidic system is still limited in published literature, which may inhibit the broad application of this technology.-Fabrication of multi-layer microfluidic chips, control of the membrane deflection to screen cell size, and printing of single cells-Microfluidic devices enabled colorimetric whole blood glucose sensing assay without the need for blood cell separation-Coiled flow inverter microreactor for controlled production of metal-organic frameworks-Method for the precise measurement of mechanical properties of single cells deformed to a large extent-Methods for the use of microfluidics to model embryonic circulation using differentiated pluripotent stem cells-Using commercially available microfluidic systems for the formation of tunable particle-size droplets loaded with growth factors-Colorimetric technique of resazurin for mass transfer characterizationThe list of papers attached to this SI collection provides essential guidelines for the fabrication of novel microfluidic systems for various applications, such as:Overall this SI should be of interest to researchers who want to establish new experimental rigs and protocols using microfluidic systems.Finally, as Guest Editor of this VSI, we would like to thank all the authors for their excellent contribution, all the reviewers for their time and valuable comments and the Methods X team for their professional supports.


Despite the neuroanatomy knowledge of the prostate described initially in the 1980's and the robotic surgery advantages in terms of operative view magnification, potency outcomes following robotic-assisted radical prostatectomy still challenge surgeons and patients due to its multifactorial etiology. Recent studies performed in our center have described that, in addition to the surgical technique, some important factors are associated with erectile dysfunction (ED) following robotic-assisted radical prostatectomy (RARP). These include preoperative Sexual Health Inventory for Men (SHIM) score, age, preoperative Gleason score, and Charlson Comorbidity Index (CCI). After performing 15,000 cases, in this article we described our current Robotic-assisted Radical Prostatectomy technique with details and considerations regarding the optimal approach to neurovascular bundle preservation. The surgical treatment for localized prostate cancer has been described beginning in the early 1900s . This stIn the following years, open retropubic radical prostatectomy with nerve-sparing technique became the standard of care for patients diagnosed with localized prostate cancer. However, the advent of robotic surgery changed the standard treatment. But even with the advantages of this technology over the open and laparoscopic approaches, erectile outcomes remain a challenge for patients and surgeons –6. RecenSeveral authors have described the neuroanatomy and physiology of erectile function. These studies have shown that corpora cavernosa neurovascular supply preservation plays a crucial role in potency recovery following RP. By conserving the arterial supply of the pudendal artery and its variants (accessory pudenda), neural ischemia is minimized. In addition, preserving the cavernous nerves at the tip of the seminal vesicles also optimizes potency recovery , 11. AnoWe have previously described different anatomical studies regarding the grades of neurovascular bundle (NVB) preservation using the prostatic arteries as vasculature landmarks. The NVB preservation is based on the medial or lateral plane of dissection of these arteries. The Grades of dissection vary from Grade one (no nerve-sparing) to five (≥95% of nerve preservation) , 15. AccIntrafascial dissection represents the plane between the prostatic capsule and prostatic fascia at the posterolateral and anterolateral portions of the prostate. At this plane of dissection, the surgeon maximizes the NVB preservation achieving the best potency outcomes. However, this plane of dissection is associated with the highest positive surgical margins (PSM) rates in T3 tumors .The interfascial space is located between the prostatic fascia layers. The NVB preservation and postoperative erectile recovery of this dissection are inferior when compared to the Intrafascial approach. When accessing this plane, the lateral prostatic fascia is resected and is visualized attached to the final specimen .This plane of dissection is located lateral to the prostatic fascia and is associated with complete NVB removal and the worst postoperative potency recovery. However, in terms of oncologic dissection, it is the safest and most indicated in patients with extracapsular extension (ECE) due to the increased margin removal , 19.Several authors have described different techniques to optimize the NVB preservation since Binder and Kramer described the first NS-RARP. In their study, ten patients with prostate cancer were operated on, and according to the authors, the NS technique combined the Walsh retrograde dissection with Campbell's anterograde approach . After mWith this approach, the prostate is lifted by the seminal vesicles, and the NVB dissection is performed from the base to the apex. After creating the inferior plane between the Denonvilliers layers, the anterior dissection creates a space between the Denonvilliers fascia, lateral pelvic fascia, and prostate. Then, the prostatic pedicle is controlled with hem-o-lok clips or bipolar . In sequInitially described by Manon et al. in 2006, this approach is also known as high anterior release of the prostate. A plane between the prostate capsule and fascia is created posteriorly at the base of the seminal vesicles. In sequence, the bilateral NVB release  is performed from 5 to 1 o’clock on the right side and from 7 to 11 o’clock on the left side. At the end of this dissection, the periprostatic tissue (Veil of Aphrodite) is suspended bilaterally, resembling a curtain from the pubourethral ligament , 22.In our routine, the retrograde release of the Neurovascular Bundles is the technique performed in all NS-RARP, despite the robotic approach (da Vinci Xi or da Vinci SP) , 23–27. After releasing the posterior portion of the prostate, the dissection is performed from the apex to the base by incising the endopelvic fascia close to the prostate and communicating the lateral with the posterior planes. At this moment, the identification of the prostatic arteries, as mentioned before, guides the Degrees of NVB preservation. In some cases, it is not possible to visualize the posteromedial and anteromedial arteries. Therefore, we perform the dissection at the usual arterial topography and cautiously peel the NVB to reach the correct planes. Finally, the prostatic pedicles are controlled with hem-o-lok clips and athermal technique.The postoperative potency outcomes of this technique were previously described by our group in a study comparing the anterograde with the retrograde approach. In this report, we have defined two groups of 172 patients who underwent NS-RARP, and the retrograde NVB dissection was associated with early potency recovery at 3, 6, and 9 months’ post-surgery .Recently, we have described the modification of our technique by performing a modified apical dissection underneath the puboprostatic ligaments preserving the maximum amount of urethra length and periurethral tissues. This technique also preserves the lateral prostatic fascia in selected patients with small tumor burden . By adop7. In our routine, the NVB preservation is planned according to the preoperative tumoral staging with imaging (MRI) and biopsy report  plays a crucial role during the posterior dissection between the DNV fascia. Using the toggle command, the scope faces the posterior aspect of the prostate (30-degrees up), achieving the optimal anatomical visualization necessary to release the NVB on both sides . FinallyIn patients undergoing full nerve-sparing, we use the landmark arteries , especiaIn patients with aggressive tumors or MRI imaging suggesting NVB invasion, we usually perform a wider dissection but still achieving a degree of neural preservation. In such cases, the dissection is guided using the lateral plane of the anterior medial and posterior medial arteries. Therefore, the arteries can be visualized attached to the prostate in the pathology analysis .After performing more than 15,000 cases, we believe that the NS-RARP learning curve and surgical technique are continuously evolving because the rates of postoperative functional and oncological outcomes are still inferior to 100%. Evaluating the results of our previous techniques is a crucial factor in identifying surgical steps that can be modified and improved. In addition, it is vital to know the prostate anatomy and physiology to respect the planes with careful dissection. We also consider that basic concepts, such as minimizing the amount of traction used on dissection, avoiding excessive cautery (energy) during hemostasis, and neural preservation based on anatomical landmarks (arteries and planes of dissection), should be common to all Nerve-sparing techniques.


Diabetes mellitus (DM) is becoming a growing risk factor for public health worldwide. It is a very common disease and is widely known for its susceptibility to multiple complications which do great harm to the life and health of patients, some even lead to death. To date, there are many mechanisms for the complications of diabetes, including the generation of reactive oxygen species (ROS) and the abnormal changes of gas transmitters, which ultimately lead to injuries of cells, tissues and organs. Normally, even if injured, the body can quickly repair and maintain its homeostasis. This is closely associated with the repair and regeneration ability of stem cells. However, many studies have demonstrated that stem cells happen to be damaged under DM, which may be a nonnegligible factor in the occurrence and progression of diabetic complications. Therefore, this review summarizes how diabetes causes the corresponding complications by affecting stem cells from two aspects: stem cells dysfunctions and stem cells quantity alteration. In addition, since mesenchymal stem cells (MSCs), especially bone marrow mesenchymal stem cells (BMMSCs), have the advantages of strong differentiation ability, large quantity and wide application, we mainly focus on the impact of diabetes on them. The review also puts forward the basis of using exogenous stem cells to treat diabetic complications. It is hoped that through this review, researchers can have a clearer understanding of the roles of stem cells in diabetic complications, thus promoting the process of using stem cells to treat diabetic complications. At present, with the improvement of living standard, the morbidity and incidence of diabetes are increasing rapidly all over the world, projected to affect 10.9% (700 million) people worldwide by 2045 . DiabetePolydipsia, polyuria, polyphagia and emaciation are typical symptoms of DM, which reduce patients’ quality of life. In addition to the harm that “more than three a little” symptoms bring to patients, the complications caused by diabetes are the major cause of death in diabetic patients . Among aThe burden of diabetic complications is directly related to cell, tissue and organ damage, and is also associated with defects in endogenous repair mechanisms. The role of their imbalance in the occurrence and development of the diseases cannot be ignored . As we aThe aim of this review was to address the specific alteration of the quality and quantity of stem cells, especially MSCs and BMMSCs, in diabetes, briefly discuss the mechanisms of stem cells damage in DM and the relationship between diabetic complications and stem cells changes, and propose a potential modality to manage diabetic complications with stem cell-based therapies. In particular, we explored the properties of diabetic stem cells in terms of 1) dysfunctions, including mobilization, differentiation potential, migration ability, cytokine secretion and et al. 2) the alteration of quantity. By understanding the body of literature devoted to these topics, researchers and practitioners may gain valuable insights into prevention, treatment, and management of diabetic complications. Additionally, it is important to illuminate the changes in the diabetic stem cells microenvironment, which may facilitate the development and improvement of future stem cell-based therapies.Despite the difference in pathophysiology, chronic hyperglycemia is the master switch of diabetic complications in both T1DM and T2DM. As the initiating factor, hyperglycemia ultimately results in endothelial dysfunctions and a variety of cells, tissues and organs damages through different pathways . The undUnder the condition of DM, the homeostasis of body is also damaged through the above mechanisms, leading to changes in cell microenvironment. Long-term exposure to diabetic microenvironment could do great harm to stem cells. The combined effects of oxidative stress, inflammation, abnormal levels of cytokines and et al. initiated by high glucose in diabetic patients may be responsible for the adverse changes in quality and quantity of stem cells . In addiStem cells are one of the damaged members which play a significant role in the development of diabetic complications. Stem cells are a population of relatively undifferentiated cells that retain the ability to divide and proliferate throughout postnatal life to provide progenitor cells that can differentiate into specialized cells. Self-renewal and differentiation ability are the most prominent characteristics of stem cells. The ability of self-renewal refers to the process in which stem cells divide symmetrically or asymmetrically to produce at least one daughter cell that retains the characteristics of stem cells . The difAmong different types of stem cells, mesenchymal stem cells (MSCs), especially bone marrow mesenchymal stem cells (BMMSCs), are most widely applied in treatments for various diseases as a novel potential therapeutic intervention . This caMobilization from BM into the circulation is the primary step for stem cells to realize their effects in cell recovery and tissue repair after injury. However, under the condition of DM, stem cells and progenitor cells suffer from “mobilopathy” and are unable to be activated for tissue repair, inducing the progression of diabetic complications.The BM niches provide the essential microenvironment for maintenance of stem cells function. Hematopoietic stem and progenitor cells (HSPCs) are important kinds of stem cells in BM which can differentiate into mature blood cells with various functions and maintain the homeostasis of blood system. Their abnormalities are related to lowered immunity, difficulty of wound healing and et al. which aggravate the complications. Adhesion molecules, chemokines, cytokines, and proteolytic enzymes form part of the microenvironment and their complex interactions are involved in the regulation of HSPCs mobilization . In diabIn addition, diabetic autonomic neuropathy is involved in the mobilopathy of stem cells. The sympathetic nervous system is prominently involved in BM-derived stem cells trafficking, and the function of sympathetic nervous system in BM is abnormal under the condition of DM. Ferraro et al. found that HSPCs are aberrantly localized in the marrow niche of the diabetic mice, and abnormalities in the number and function of sympathetic nerve termini are associated with this mis-localization. The MSCs innervated by these sympathetic nervous system fibers fail to downregulate chemokine CXCL12 in response to G-CSF or adrenergic stimulation, thus inhibiting the release of HSPCs from BM and making it aberrantly localized in the marrow niche . Furthervia a mitogen-activated protein kinase kinase-p38-signal transducer and activator of a transcription 3-dependent pathway . As one of the most common and severe complication of DM, DCM is characterized by abnormal myocardial metabolism, diastolic cardiac dysfunction, heart failure, cardiomyocyte hypertrophy, cardiac fibrosis and even death in severe patients . It has Many patients with diabetes, both T1DM and T2DM, also suffer from an increased risk of osteoporosis-associated fractures according to the influence of DM on skeletal metabolism. In T1DM, patients have reduced bone mineral density (BMD) which may ultimately increase risk of fracture . This suMost diabetics usually weigh in an abnormal range, either overweight or underweight and some of them also have lipodystrophy. Lipodystrophy is an adipose dysfunction in which your body produces, uses, and stores fat. This kind of disease is mainly related to the obstacle of differentiation of adipose derived stem cells (ASCs) . ScientiMoreover, male reproductive disorder are serious complications of T1DM. There are three main cells in the male reproductive system that are related to the disorder, spermatogonia stem cells (SSCs), Sertoli cells and Leydig cells. T1DM results in the inflammation development in the testes and further decreases the number of Leydig cells located in the interstitial tissue of testicles. A great decrease in the number of Leydig cells thus decreases the testosterone level and disturbs the differentiation ability of SSCs. On the contrary, Sertoli cells are hardly affected and form a niche for SSCs, thus minimizing the severity of spermatogenesis disorders in T1DM .in vivo indicate that the differentiation abilities of stem cells in diabetic microenvironment are modified. Interestingly, an in vitro study found that the properties of stem cells impaired by the diabetic inner environment seems to be irreversible. BMMSCs cultured in vitro under normal culture conditions possess decreased myogenic differentiation in induced differentiation experiment, suggesting that the impairment cannot be recovered by ex-vivo culture  has been found under diabetic environment. The delayed wound healing in diabetes is closely related to it . Accordivia suppression of proinflammatory genes and inhibition of TGF-β1/Smad2 signaling pathway, respectively , which reflects poor glycemic control, significantly inhibits MSCs proliferation .Additionally, the location of stem cells may also be connected with their quantity. The number of circulating endothelial progenitor cells (EPCs) significantly decreases in BM and peripheral blood, but paradoxically increases in spleen under diabetic conditions. This may be attributed to the damage of EPCs production in BM and the reduction of mobilization of spleen EPCs . Howevervia secretion of various factors. Thus, the number of SCCs with c-kit-/CD90+ immunophenotype significantly decreases and the number of differentiating c-kit+/CD90+ SSC and CD51-/CD24+/CD52+ SSCs significantly increases (A study further claimed that this quantity change was not overall or random. For ASCs, diabetes selectively depletes a subpopulation with a highly vasculogenic transcriptional profile, thus impairing new blood vessel formation and wound healing . Among tncreases .in vitro experiments and animal experiments. But to the best of our knowledge, existing clinical studies are of low quality and none has proven clinical safety nor efficacy (We can see that diabetes indeed does damage to the endogenous stem cells of the body in all aspects, which leads to severe diabetic complications. Therefore, it is possible that exogenous stem cells can be used to treat the complications. Some studies have reported the effectiveness of the treatment basic efficacy . Here, wDiabetes damages stem cells from quality and quantity. In most cases, the number of stem cells decreases under DM. Therefore, supplementing exogenous stem cells can relieve the damage of diabetes on the quality of stem cells. Additionally, stem cell dysfunctions caused by diabetes can also be relieved through the normal function of exogenous stem cells. Three specific mechanisms might play a role, including migration, differentiation and secretion ability. Firstly, stem cells undergo homing and further migrate to the injured site, which may be due to chemoattraction mediated by cell surface receptors . SecondlThe microvascular complications of diabetes mainly include retinopathy, neuropathy, and nephropathy. These three major microvascular complications seriously affect the quality of life of diabetic patients and even threaten their lives. Stem cells seem to be an effective long-term treatment option for these complications due to their repair and regeneration potential.It has been reported that stem cells may delay the progression and alleviate the symptoms of diabetic retinopathy through secretion and differentiation abilities . Recent Effectiveness for reversing various manifestations of experimental diabetic neuropathy has also been proved through attempts for treating experimental diabetic neuropathy with BM-derived stem or progenitor cells. In previous studies, MSCs transplantation has been reported to have therapeutic effects on diabetic neuropathy through paracrine actions of growth factors . AdditioFor the treatment of diabetic nephropathy, some studies have reported that in the presence of certain growth factors, embryonic stem cells can differentiate into renal cells and play a therapeutic effect on diabetic neuropathy . iPSCs hDiabetic patients are prone to atherosclerosis, and eventually develop into macrovascular complications. Vascular stem cells have the ability to differentiate into EPCs, which is a potential target for the treatment of diabetic macrovascular complications .Diabetes causes various stem cells dysfunctions such as mobilopathy, abnormal differentiation, migration dysfunctions, secretory dysfunctions and et al. through different molecular pathways. DM also results in abnormal changes in the number of stem cells, which may due to abnormal proliferating rate, increased apoptosis and et al. These may further lead to diabetic complications, which are the main cause of high mortality in patients with diabetes.Fortunately, in the past few years, the role of stem cells in the treatment of diabetic pathology and related complications has been widely studied. The ability of stem cells to regenerate and differentiate makes it possible for researchers to explore their potential in treating diabetic complications. It has been suggested that normal functional exogenous stem cells might improve microvascular complications and macrovascular complications, which are the major complications of DM. This therapeutic approach not only helps to overcome the limitations of modern treatment, but also provides a new way for long-term treatment of diabetic complications. Therefore, the use of exogenous stem cells in the treatment of diabetic complications is very promising, worthy of further exploration. However, it can’t be denied that stem cells therapy for diabetic complications is still in the imperfect stage of exploration. Extensive research is needed to establish a standard procedure for stem cells therapy of diabetic complications. We hope that this review can provide an in-depth understanding of the association between stem cells and diabetic complications, pave the way for novel insights into the mechanisms underlying diabetes complications, and inspire more researchers to explore new methods for the treatment of diabetic complications.