Tremendous progress has been advanced by research into graphene and its derivatives with great benefits toward low-cost, portable, and real-time tactile sensors/electronic skin.The review presented herein direct future efforts aimed at high-quality graphene-based tactile sensors and their implications for the wider scientific community.The paper also are informative regarding some basic and crucial issues regarding graphene and its derivatives, such as charge-transport principles, doping/trapping behaviors, correlations between structure/morphology and properties/functions. Skin is the largest organ of the human body and can perceive and respond to complex environmental stimulations. Recently, the development of electronic skin (E-skin) for the mimicry of the human sensory system has drawn great attention due to its potential applications in wearable human health monitoring and care systems, advanced robotics, artificial intelligence, and human–machine interfaces. Tactile sense is one of the most important senses of human skin that has attracted special attention. The ability to obtain unique functions using diverse assembly processible methods has rapidly advanced the use of graphene, the most celebrated two-dimensional material, in electronic tactile sensing devices. With a special emphasis on the works achieved since 2016, this review begins with the assembly and modification of graphene materials and then critically and comprehensively summarizes the most advanced material assembly methods, device construction technologies and signal characterization approaches in pressure and strain detection based on graphene and its derivative materials. This review emphasizes on: (1) the underlying working principles of these types of sensors and the unique roles and advantages of graphene materials; (2) state-of-the-art protocols recently developed for high-performance tactile sensing, including representative examples; and (3) perspectives and current challenges for graphene-based tactile sensors in E-skin applications. A summary of these cutting-edge developments intends to provide readers with a deep understanding of the future design of high-quality tactile sensing devices and paves a path for their future commercial applications in the field of E-skin. A tactile sensor is a kind of device that simulates the tactile sense of human skin and can detect and analyze the strength, position and time sequence of an external mechanical force with micron-level resolution by micro/nano processing technology and intelligent data analysis. As one of the most important sensor components in electronic skin (E-skin), tactile sensors have become a popular international research area due to their potential applications in wearable human health monitoring and care systems, advanced robotics, artificial intelligence, and human–machine interfaces. Among all kinds of tactile sensors, flexible, low-cost, conformal, portable and wearable real-time-monitoring functional electronic devices based on graphene and its derivatives should be generally concerned as the next generation of sensing devices for E-skin applications –5. On onWith a special emphasis on the state-of-the-art works published in 2016, these latest developments use the most advanced methods of material assembly, device construction and signal characterization and represent the forefront of graphene-based tactile sensors, laying the foundation and identifying the direction for future commercial applications. The main contents of this review provide a general synopsis on the functional supramolecular nanoassemblies of graphene and its derivatives with respect to progress during the tactile sensing era for E-skin applications. Some historically significant seminal works achieved before 2016, which are of paramount importance in shaping this field, are also highlighted to provide a foundation. For other interesting yet earlier studies, we encourage the interested readers to consult other excellent reports. This review is organized as follows: First, we briefly introduce the related concepts and preparation methods of graphene and its derivatives for tactile sensors. Then, with an emphasis on the impactful protocols of how to improve the performance of this kind of sensor, the unique roles and advantages of the employed graphene materials are discussed and highlighted by addressing representative paradigms. Finally, the current perspective and challenges of graphene sensors are outlined. We hope that the discussions will be beneficial to future investigations aimed at high-quality graphene-based tactile sensors.sp2-hybridized crystal structure, where each carbon atom has three equivalent valence orbitals  together in a plane forming a triangle and a pz orbital perpendicular to the basal plane, which arranges the carbon atoms in a honeycomb lattice. The hybridization of one s and two p orbitals leads to the formation of covalent σ-bonds with other neighboring carbons, and the pz orbitals overlap each other to form delocalized π-bonds; the abundant delocalized electrons are responsible for the extraordinary electronic properties of graphene. The concentration of the electrons and holes of graphene can up to 1013 cm−2, and the mobility can reach 200,000 cm2 V−1 s−1 [Since Geim and Novoselov discovered graphene in 2004, it has received tremendous attention as an ideal material to construct electronic devices due to its unique physical properties . As is k V−1 s−1 –20. Thisπ–π stacking [π-conjugated molecules to realize a responsiveness to various stimuli, confirming graphene materials to be excellent scaffolds for various sensors [Additionally, graphene has a perfect 2D structure, which offers abundant active sites on the basal plane to react with functional groups by means of conjugation reactions or the absorption of various functional moieties via hydrophobic interactions, dipole–dipole interactions, or stacking . This chstacking –24. Part sensors –30.Moreover, graphene materials also possess excellent transmittance and mechanical properties with light transmittances of up to 97.7%, fracture strains of up to 25% and a Young’s modulus of ≈ 1.1 TPa, which provide graphene a significant opportunity for the construction of flexible and stretchable electronic devices used in tactile detection , 32.Most importantly, many studies have discussed the physical properties of graphene and its sample preparation routes –35. For C) of a parallel plate capacitor can be defined as C = ε0εA/d, where ε0, ε, d, and A are the vacuum dielectric constant, the relative permittivity of the elastomer dielectric, the distance, and the overlapped area between the two parallel plates, respectively. With excellent electrical properties, mechanical flexibility and optical transmittance, graphene has become one of the most promising materials for electrodes in tactile piezocapacitive sensors.In recent years, great progress has been made in fabricating pressure sensors based on different sensing mechanisms, including capacitive , 43, traFor example, to obtain a tunable-sensitivity flexible pressure sensor, a classic method was employed by Luo and coworkers, wherein graphene was used as the electrodes, and polydimethylsiloxane (PDMS) pyramids with different spacings were used as the dielectric layer . By a th2 wafer by wet etching. (3) On another substrate, a piece of Si/SiO2 wafer was patterned by deep reactive ion etching to form an array of circular or hexagonal holes of a given diameter, periodicity and depth, arranged in various patterns such as a hexagonally packed lattice. (4) The graphene-polymer membrane was aligned with the patterned SiO2 surface using a tape-supported transfer process. It was found that sensors covering an area of just 1 mm2 showed reproducible pressure transduction under static and dynamic loading up to pressures of 250 kPa. The measured capacitance change in response to pressure was in good agreement with calculations.In the above configurations, the tunable sensitivity was obtained by changing the space between the pyramids or the morphology of graphene; indeed, the tunability of the suspended membrane area and the dielectric gap were the most important factors to the sensing performance Fig. b. Althoue-beam evaporation, which are generally tedious to work and crosstalk between adjacent cells is inevitable. These drawbacks can be overcome simply by replacing the dielectric layer. Nylon netting composed of polyethylene terephthalate (PET) is a flexible, low-cost insulating polymer with a regular microporous structure and excellent mechanical properties, and was first selected and sandwiched between graphene films by He et al. [The microstructure dielectric layer of the abovementioned devices to some extent can overcome the slow response and relaxation times caused by the high viscoelasticity of PDMS, leading to a substantially higher sensitivity and faster response/relaxation time. However, the construction of such capacitive sensors often requires intricate processes such as traditional lithography and e et al.  as the d−1), rapid response (≈ 70 ms), and high stability over 2500 cycles of loading/unloading. The authors also demonstrated a pixelated sensor array for pressure mapping without any significant crosstalk between adjacent cells, as shown in Fig. An air gap between the surrounding spacers in each tactile cell is another effective method to reduce the difficulty in capacitive tactile sensor preparation. Pyo et al.  presente2 and 8 × 8 array (64 channels) was fabricated by Kang and coworkers [From the above examples we can see that most of the capacitive tactile sensors have mainly focused on pressure or strain sensors that transduce physical touch into electronic signals, which cannot fulfill the demands of E-skin applications. Indeed, in addition to a position-sensing capability through contact, a 3D-sensing capability for the recognition of 3D shapes and the distance of approaching objects before contact occurs is significantly important both in wearable electronics applications and in the robotics field . Furtheroworkers . As disp4HCO3 in a PDMS sponge, Kou and coworkers achieved a composite. When the sponge was sandwiched between two electrodes, a flexible wireless pressure sensor with a high sensitivity, wide operating rage, rapid response time, low detection limit, and good stability was obtained [Graphene and its derivatives are versatile and sometimes can be used as a good dielectric material for capacitive pressure sensors. By adjusting the proportion of graphene and NHobtained . Ho et aobtained  developeobtained . By utilobtained . With a As seen from the above examples, both graphene layer and graphene foam can be used to construct high-performance capacitive tactile sensors. Graphene layers with good morphology, high crystallinity and uniform thickness are usually obtained through CVD. The graphene electrodes of capacitive tactile sensors obtained in this way not only present excellent electrical properties but also control the transparency through altering the growth process. Furthermore, the electrodes can also conform to substrates of different surface morphologies, thus, realizing the patterning of electrodes and ultimately improving the tactile sensitivity of devices. What is more interesting is that the CVD method can achieve large-area graphene layers, making the realization of integrated of tactile sensor components easier and laying a solid foundation for tactile sensors with good spatial resolution. However, the high energy consumption, high cost and high pollution stemming from the production process pose difficulties to realizing industrial production. In contrast, graphene foams are usually obtained through GO, which can be prepared in large quantities by solution methods at room temperature. Furthermore, GO has different electrical properties due to the varying degrees of reduction, which enables it to be used as both electrodes and the insulating layer of capacitance tactile sensors. When the graphene foam, which is porous and flexible, acts as the dielectric layer, the distance between the two parallel plates is easily adjusted under the action of external forces, thus, greatly improving the sensing performance of capacitive tactile sensors. However, even with a strong reduction, the oxygen-containing functional groups do not completely disappear, which greatly reduces the crystallinity and conductivity of RGO, and results in the material not being a good electrode for capacitive tactile sensors. Therefore, due to the graphene layer and the graphene foam having respective advantages and disadvantages for constructing capacitive tactile sensors, suitable forms of graphene and its derivatives with different morphologies should be chosen according to the actual practical applications.R = ρL/A, where ρ is the resistivity, L is the length, and A is the average cross-sectional area. When sensors are in operation, various related parameters are used to evaluate their qualities. Among them, the most fundamental parameter is the gauge factor (GF), which reflects the sensitivity to external physical action. The GF is defined as GF = (∆R/R)/ε, where ΔR/R is the normalized resistance and ε is the mechanical strain/pressure. A higher GF means a higher sensitivity [Although capacitive tactile sensors based on versatile graphene materials forge ahead on wearable electronic devices, it has been widely accepted that high sensitivity, high resolution, and mass production can hardly be realized at the same time, and the constructed devices are still far from practical uses. Owning to the excellent electrical property of graphene and its nanoscale flexibility, minor stress deformations could lead to a dramatic change in resistance . Therefositivity . To achiAs the high aspect ratio of 1D architecture favors the rapid capture and release of external stimuli, increasing effort has been focused on fabricating pressure sensors based on 1D active material. However, the innate 2D structure of graphene makes obtaining 1D microscopic structure difficult. Thus, we need to search for other tools to help. As reported by Nakamura and coworkers, using a nickel wire as a template, 1D hollow tubing CVD graphene fibers (TGFs) could be obtained, coated with PDMS, and used as the active material for resistance-type strain sensors, as shown in Fig. Electrostatic spinning is a special fiber manufacturing process in which a polymer solution or melt is sprayed in a strong electric field. By taking advantage of this commonly used method, composite nanofibers of carbon nanotubes and graphene were fabricated by Lee et al.  as showc, whereiGO and RGO contain abundant oxygen functional groups on their basal plane and edges, which make their self-assembly into 1D fiber architectures via solution processes possible. Fu and coworkers prepared a kind of conductive glass fibers (GFs) fabric by dip-coating GO on the surfaces of GFs, followed with an HI reducing process . Taking With the increasing demand for high-conductivity films, 2D graphene films have attracted significant attention due to their transparency and flexibility for wide-ranging application in optoelectronics, light-emitting diodes, solar cells, and sensors . For tac3/Ar plasma treatment of graphene, changed its morphology, structure, chemical composition, and electrical properties. Due to the tunneling behavior originating at localized defects, the graphene structure doped with nitrogen atoms exhibited a significant increase in sensitivity by one order of magnitude compared to that of the unmodified graphene sheet, as shown in Fig. −1) was obtained, substantially higher than that of tactile sensor devices with relatively flat graphene electrodes. More interestingly, as the complete separation of the two graphene layers occurred when the sensor was not subjected to any pressure, such a device could be used as an on/off and energy-saving device.In addition to directly using CVD graphene as an active material in tactile sensors, the modification and microstructure of graphene can further improve the sensing performance of devices. From the point of view of material modification, Haniff et al.  found thAlthough CVD graphene-based tactile sensors show the high sensitivity and reliability needed for sensor devices, their low yield, high production costs, and complex processes hinder their development toward practical applications . Fortunaπ–π interface interactions between graphene sheets, those 3D materials with an ultralight density and flexibility also possess a high conductivity and mechanical strength. In addition, their scalable production makes for an attractive choice for practical implementation [Active materials based on a 3D porous structure are the most common well-shaped and self-supported graphene hierarchical nanostructures used in graphene-based tactile sensors. Based on the large stacking interfaces and the entation . Recentlentation –78, varientation –81, cellentation , multilaentation , all kinentation –86, and entation –89.A typical example using commercially available PU and PVC sponges as templates was reported by Zhang et al., wherein graphene-wrapped sponges were obtained by soaking sponges in a hydroquinone/GO mixed solution and then vacuum annealing under certain conditions . The as-As is known, the majority of sponges provided on the market are PU sponges. The production process for this kind of chemical product is neither environmentally friendly nor conducive to human health, so tactile sensors based on PU sponges are difficult to realize for practical applications of E-skin , 83. To In addition to natural fabrics, paper is another kind of environmentally friendly substrate with a 3D hierarchical nanostructure and good elasticity that also has potential to be a good alternative to improve the performance of pressure sensors. A typical paradigm was reported by Tao et al. , who mixAlthough the 3D graphene structures prepared through the abovementioned templates can significantly improve the sensing performance of tactile sensors, the opacity of sponges, fabrics and tissue paper hinders the construction of transparent E-skin , 92. PDMBeyond PDMS, other flexible porous polymers, such as porous inverse opal acetylcellulose (IOAC) films, thermoplastic polyurethane electrospun fibrous mats, poly, polyester textiles, and polyaniline (PANI) can also be used as templates to construct 3D graphene structures –97. The 2) and Ecoflex with such a GPN. It was found that the conformal nanostructure of MoS2 on the GPN surface could produce improved resistance variations against external strain and pressure. As a result, the MoS2/GPN/Ecoflex sensor exhibited noticeably improved sensitivity over that of previously reported GPN/PDMS sensors in a pressure test. Copper foil, as the most commonly used metal for the preparation of graphene by CVD, has also been used to fabricate porous graphene 3D structures [Flexible and transparent polymers to some extent can solve the problem of sensor transparency. Nevertheless, all of the porous structure cannot effectively remain in sensors after the polymer has infiltrated into the as-prepared graphene foam, and the pores can achieve enhanced sensing performances , 98. To ructures , 84.Fig.−1, an ultralow detection limit of approximately 0.1 Pa, and a superior separation of 0.2-pascal-scale difference.Generally, the size and distribution of the pores in the foam, as well as the thickness of the pore walls, are essential to the sensitivity of graphene foam-based pressure sensors . Therefoπ–π interactions. Then, the formed emulsions were immediately immersed into liquid nitrogen for 10 min to keep their macroporous structure. (3) The aerogels were obtained after lyophilization and a thermal treatment. Thereafter, the authors used polyethylene glycol sorbitol monooleate (Tween 80), instead of SDS, as a sparkling agent, and an automatic egg beater, instead of a blender, to obtain a sparkling graphene block (SGB) with bubbled cavities maintained well, as illustrated in Fig. −1), making this material a promising candidate for applications in actuators, elastic conductors, strain/pressure sensors, and wearable devices, as shown in Fig. 2, GaN, and CdS, to the graphene aerogel 3D structure could enhance the tactile sensing properties, where the piezoresistive response was considerably higher than that of the bare aerogel [To fabricate graphene aerogels with ultralight, superelastic, and excellent mechanical and multifunctional properties, surfactants and crosslinkers are often employed in the synthesis system –102. Qu’ aerogel , 105.FigFrom the abovementioned 3D graphene-based tactile sensing paradigms for E-skin applications, we can see that most of the developed strategies focused on high sensitivity, while sensors capable of combing high sensitivities and broad dynamic ranges have barely been proposed. This inequality is because such materials are prone to saturation responses when attempting to obtain measurements involving high pressures . By meanAs we all know, many well-adapted hierarchical structures have been developed through natural selection and are critical for the survival of organisms. For example, to climb a vertical wall, the feet of the gecko have developed a kind of special hierarchical structure so that maximized contact area and intermolecular interactions could be realized , the sel−1 over a wide linear range of 0-2.6 kPa. As shown in Fig. By using a bioinspired hierarchical structure based on the surfaces of organs and consisting of PDMS covered with monolayer graphene Fig. a, Bae anExcept for human epidermis, the epidermal ridges on the skin of the human fingertip, which serve to amplify subtle external stimulations, can also inspire us to design highly sensitive fingertip skin-like pressure sensors. As shown in Fig. In addition to human organs, microstructures from animal and plant organs also provide interesting ideas for the preparation of active materials for graphene-based tactile sensors. A more obtrusive example is the Shar-Pei dog, and the higher dimensional patterns of Shar-Pei skin can sustain large in-plane stretching and still provide tactile perceptions so that wrinkle-crumple RGO electrodes with a high stretchability and strain-insensitive resistance profiles were fabricated by means of sequential deformation processes, as shown in Fig. With the rapid development of materials science, micronano materials with various morphologies and functions have been designed and synthesized. To advance the applications of E-skin, these materials can be integrated with versatile graphene materials in various ways to achieve effects in tactile sensors exemplifying that the combination can be greater than the sum of the individuals .ZnO, as a common inorganic semiconductor possessing a large bandgap and exciton binding energy, an inherently high transparency and excellent luminescence at room temperature, has become a celebrated material widely used in liquid crystal displays, thin-film transistors, light-emitting diodes and other electronic products, particularly tactile sensors , 87. SunIn addition to ZnO, other inorganic materials can also be employed to construct functional composites to enhance the sensing performance of tactile sensors. For example, Ma et al.  synthesiAs an important member of the material family, polymers present many excellent properties, such as light weight, mechanical flexibility, and their generally good solution processability, as well as a good compatibility with large-area and flexible solid supports; all of these characteristics cannot be matched by other materials and endow polymers with the ability to manufacture various sensing devices . FurtherPoly(vinylidene fluoridetrifluoroethylene) (P(VDF-TrFE)), as a natural elastic conductive building block, is usually functionalized with graphene materials and has widely been used in the piezoresistive sensors , 127. Fo−1 at 3–1000 Pa and a high stability for 20,000 loading–unloading cycles could also be obtained [The abovementioned graphene/polymer composites were fabricated by simply mixing graphene and polymers together, hardly yielding well-defined composite materials and negatively affecting the performance of pressure-sensing devices based on such materials. To solve this problem, Lin and coworkers prepared a highly flexible self-healing conductive polymer composite consisting of graphene, poly(acrylic acid) and amorphous calcium carbonate by a biomineralization-inspired process . Strain obtained . Furtherobtained . The GF π-conjugated graphene fragments, GO, as a novel cousin of graphene, can be considered as a 2D surfactant for use as a dispersing agent or to generate Pickering emulsions [−1 and could detect subtle pulse beats and monitor various human movement behaviors in real time , metal carbides and nitrides (MXenes), and montmorillonite (MMT), have recently become a focus for advanced electronics [Another example related to reducing the efforts and cost of the fabrication techniques for the FET-based tactile sensor configuration was reported by Sahatiya and coworkers, wherein 2D graphene/MoSthe gate . Owing tctronics . From anctronics . Althougctronics . Howeverctronics . HoweverAlthough FET-based tactile sensors are generally very sensitive, easily integrated, realize real-time detection, the touch point of the abovementioned FET pressure sensors are mostly located in the gate or channel region . As a re−1, a limit of detection < 1 kPa, and a response time of ≈ 30 ms (Fig. In addition to piezopotential MIM capacitors, the induced triboelectric potential can also be able to couple with FETs for modulating the carrier transport in semiconductor channels and helping to obtain high-performance devices . For exa ms Fig. b. Meng eRecently, targeting high-performance graphene-based tactile sensors, great progress has been achieved mainly in terms of the sophisticatedly designed morphologies of graphene and its derivatives, the working principles aiming at providing a fundamental knowledge of the sensing processes, state-of-the-art protocols targeting high-performance sensing, and the development of synergy with other materials. Indeed, the tremendous advancements accumulated to date have brought tactile sensors a significant step closer to the potential applications of flexible and wearable E-skins, such as health monitoring devices, artificial intelligence, and human–machine interfaces. Continuous efforts to further improve the overall qualities of this kind of sensor, including sensitivity, detection range, pattern recognition and spatial resolution of external forces, response time, stability and reproducibility, limit of detection, capability of digital and intelligent readouts, real-time workability, etc., remain strongly desired. To achieve this improvement, the following aspects will continue to be the major subjects of this field in our opinion.First, the synthesis, assembly and modification of high-performance graphene materials are the basis for the fabrication of high-performance graphene-based tactile sensors. As we mentioned above, graphene and its derivative materials were usually used as conductive electrodes or sensitive materials. As electrodes, graphene has a variety of intrinsic excellent physical properties, such as a high electrical conductivity, transparency, and flexibility, which lay a good foundation for building high-performance wearable devices. However, on one hand, it is difficult to industrialize the production of large-area, high-quality materials via current production technology. On the other hand, ultrathin 2D structures are easily damaged during scratching by external forces, and the reuse of devices can only be realized through the application of complex packaging technologies. Therefore, exploring the preparation process of graphene electrodes remains the basis for commercial applications of graphene-based tactile sensors. From the point of view of sensitive materials, graphene materials are easy to assemble; are easy to modify; are easy to combine with other materials, enabling them to have diverse morphologies and properties; and can be used to improve the performance of tactile sensors. However, as a zero-bandgap semiconductor, the on/off ratio of graphene is relatively low, and the current is difficult to modulate. Although there are many ways to open the bandgap in graphene, these remain in the laboratory. Therefore, scientists should do their best to explore simpler and more effective ways to realize the commercial applications of graphene as an active material.Second, the launch of emerging sensing mechanisms in terms of molecular engineering, supramolecular assembly, and their combination with other protocols will undoubtedly be among the most important ways to construct new types of high-performance tensile sensors. For example, a self-powered sensation matrix could be constructed by sandwiching piezoelectric polymer materials between two graphene electrodes , 150. AcAs we have highlighted, numerous sophisticated strategies have been proposed to achieve high-performance tactile sensors based on graphene materials. However, most of the abovementioned works address only one or a few aspects of a sensor’s quality, which is still far from mimicking human skin. Clearly, a mechanically flexible and fully integrated sensor array for multiplexed monitoring of an individual’s activities, without interrupting or limiting the user’s motions, is still a formidable challenge that cannot be realized by a single capacitive-style, piezoresistive-style or FET-style array. The combination of a couple of the state-of-the-art strategies might be among the most feasible ways to address this topic to some extent.Finally, multifunctional tactile sensing devices capable of digital and intelligent readouts are important issues required by modern E-skin applications. Therefore, the construction of high-performance tactile sensing device arrays along with effective pattern recognition algorithms is particularly important. We believe that with the joint efforts of scientists in chemistry, physics, material science, micronano processing, computer science and other disciplines, the construction of high-performance graphene-based tactile sensing systems for potential commercial uses will soon become a reality.


Tolypocladium inflatum. The suggested nomenclature was proved feasible by naming introns present in mitogenomes of 16 fungi of different phyla, including both basal and higher fungal lineages although minor adjustment of the nomenclature is needed to fit certain special conditions. The nomenclature also had the potential to name plant/protist/animal mitochondrial introns. We hope future studies follow the proposed nomenclature to ensure direct comparison across different studies.Fungal mitochondrial genes are often invaded by group I or II introns, which represent an ideal marker for understanding fungal evolution. A standard nomenclature of mitochondrial introns is needed to avoid confusion when comparing different fungal mitogenomes. Currently, there has been a standard nomenclature for introns present in rRNA genes, but there is a lack of a standard nomenclature for introns present in protein-coding genes. In this study, we propose a new nomenclature system for introns in fungal mitochondrial protein-coding genes based on (1) three-letter abbreviation of host scientific name, (2) host gene name, (3), one capital letter P (for group I introns), S (for group II introns), or U (for introns with unknown types), and (4) intron insertion site in the host gene according to the cyclosporin-producing fungus The online version of this article (10.1186/s43008-019-0015-5) contains supplementary material, which is available to authorized users. Fungi constitute a huge group of highly diverse organisms, with 2.2–3.8 million estimated species and 144,000 currently known species on Earth    as the reference mitogenome. The 25,328-bp mitogenome of T. inflatum contains all the 15 protein-coding genes typically found in fungal mitogenomes, and there is no intron in any of these protein-coding genes , which is fast when aligning long sequences containing many introns and can always generate satisfactory alignment according to our experience. The default setting of MAFFT works well in most cases. If exon-intron boundaries are not correctly identified (probably due to the interference of intron sequences or presence of short exons) under the default settings, one may consider adjusting the alignment parameters  and/or importing additional sequences to align from a species closely related the test species. In addition, it is always advisable to refer to known annotation results and/or characteristic nucleotides at splice sites of group I/II introns  from Candida glabrata cox1 at position 240. Other examples are included in Table We propose a new nomenclature system for introns in fungal mitochondrial protein-coding genes based on 1) three-letter abbreviation of host scientific name, 2) host gene name, (3) one capital letter P , S , or U (for introns with unknown types), and (4) intron insertion site in the host gene according to  three-le host gennad5 in Candida pseudojiufengensis (Cpse.nad5U717) and Candida psychrophila (Cpsy.nad5P717)   Table . The intfungi from different phyla, including both basal and higher fungal lineages . From the intron insertion site numbers, one can also easily understand the phase of an intron, which is phase 0 when an intron inserts between two codons , and phase 1 or 2 when an intron inserts within a codon . These introns are often found at highly conserved regions  also contain group I or II introns in their mitochondrial genes  that are absent in fungal mitogenomes . Insertion site of group I introns are shown in red, group II introns in green, and introns with undetermined intron types in shade. (DOCX 21 kb)Sequences of protein-coding genes of Additional file 2:cob, cox1, cox2, nad1, and nad5 of different fungal taxa plus few non-fungal taxa were aligned by MAFFT, and visualization of the aligned sequences was performed using ESPript 3.0 (Robert and Gouet Intron insertion sites for 22 common introns. Exon sequences of


P = 2.66 × 10–4). Moreover, applying enterotyping on our samples stratified microbiomes into A, B, and C dermotypes. Dermotype C included overrepresentation of Pseudomonas, Staphylococcus and Stenotrophomonas and was markedly associated with delayed healing of RID. Strikingly, coexistence of diabetes mellitus and RID was remarkably correlated with a significant overrepresentation of Klebsiella or Pseudomonas and Staphylococcus. Metabolic abilities of skin microbiome could support their potential roles in the pathogenesis of RID. Cutaneous microbiome profiling at the early stages of RID could be indicative of prospective clinical outcomes and maybe a helpful guide for personalized therapy.Radiotherapy-induced dermatitis (RID) is an inflammatory cutaneous disorder that is acquired as an adverse effect of undergoing radiotherapy. Skin microbiome dysbiosis has been linked to the outcomes of several dermatological diseases. To explore the skin microbiota of RID and deduce their underlying impact on the outcome of RID, cutaneous microbiomes of 78 RID patients and 20 healthy subjects were characterized by sequencing V1-V3 regions of 16S rRNA gene. In total, a significantly apparent reduction in bacterial diversity was detected in microbiomes of RID in comparison to controls. Overall, the raised Proteobacteria/ Firmicutes ratio was significantly linked to delayed recovery or tendency toward the permanence of RID (Kruskal Wallis:  Recently, Egypt recorded an exponentially increased rate of cancer patients. Radiotherapy is substantially considered as a key element of treatment in breast cancer and nearly is applied to > 70% of cancer patients5.Worldwide, there is a raised incidence of cancer6. Overall, cutaneous dermatitis negatively affects individuals’ health and quality of life. Pathophysiology of cutaneous dermatitis was linked to a multitude of predisposing factors that could cause a disturbance in proinflammatory and profibrotic cytokines8. These factors include genetic and epigenetic predisposition in addition to arterial insufficiency, diabetes mellitus, chronic osteomyelitis, radiotherapy-induced dermatitis (RID), rheumatoid arthritis, skin tumors, trauma and venous ulcers10. Distinctly, the vast majority of cancer patients experience skin reactions upon radiation exposure. Several risk factors are assumed to directly trigger or influence the incidence and severity of RID. These risk factors may be intrinsic including age, ethnicity, gender, malnutrition, location and stage of the tumor, and concomitant diseases such as systemic inflammation and diabetes mellitus. While extrinsic factors include the kind and total dose of treatment, volume of treated area and radiotherapy technique11, in addition to bacterial infections12.Although the rapid advances in radiation oncology improved the effectiveness of cancer treatment, skin reactions, which are defined as radiation dermatitis, remain the most common adverse effect of radiation toxicity14.The anatomical and physiological structures of human skin represent the protective shield of the human body. The human skin is influenced by the surroundings and is the site where billions of microbial communities collectively constitute a unique ecosystem that constantly modulates host immunity and metabolism. The normal functions of human skin basically require integral collaborations between epidermal barriers, skin immunity and microbial inhabitants. Both the composition and structure of the microbial ecosystems associated with the human skin are influenced by several factors which include host-related such as age and gender, in addition to external stimuli as weather, lifestyle, and use of medicated preparationsDespite the skin microbiomes have been intensely investigated over the past years for their implication in several dermatological disorders, their roles in the pathogenesis and prognosis of RID demand comprehensive investigations. We aimed to provide new insight into the potential impact of skin microbiome on the prognosis of RID.The present study was approved by the ethics committee of the Faculty of Pharmacy, Port Said University, Egypt (Reference no. A-6-2019). This study was carried out following the principles of the Declaration of Helsinki. Recruited patients in this study provided informed consent at sampling time.16. The inclusion criterion was mainly based on patients with newly diagnosed and grade 2 confirmed RID. The exclusion criteria were: (1) systemic antibiotic intake; (2) topical application of corticosteroids and antibiotics. Besides, healthy subjects were involved in the current study. All recruited patients provided informed consent prior to sampling.This study was performed for over 16 months (between June 2019 and September 2020). Participants were prospectively enrolled at outpatient clinics of dermatology department, Al Mabarrah Health Insurance Hospital, Zagazig, Egypt. The prognosis of RID was identified by follow-up of patients for 12 months. Diagnosis and grading of RID were carried out according to CDC Cutaneous Radiation Injury: Fact Sheet for Physicians17. The collected swabs were used for genomic bacterial DNA extraction using DNeasy PowerSoil Kit Catalog No. 12888  with previously reported modifications18. V1-V3 hypervariable regions of 16S rRNA gene were amplified using the following primers (underlined bases define adaptors): Forward Primer 5′ AATGATACGGCGACCACCGAGATCTACACATCGTACGTATGGTAATTC AATTACCGCGGCT GCTGG; Reverse Primer 5′ CAAGCAGAAGACGGCATACGAGATAACTCTCGAG TCAGTCA GCCGAGTTTGATCMTGGCTCAG19. Then, PCR amplicons were sequenced by Illumina MiSeq at IGA Technology Services .Skin swabs were collected from patients by rubbing the site of RID with a premoistened swab (0.15 M NaCl with 0.1%Tween 20). Also, antecubital fossa, represents the moist sites, was rubbed by swab for collecting specimens from healthy subjects20, which included: trimming, filtering and denoising of row reads as previously described 21. Finally, high-resolution RSVs were generated by removing the potential chimeric sequences.The analysis and classification of 16S rRNA reads were mainly based on ribosomal sequence variants (RSV). QIIME2 platform with DADA2 plugin was used for sequence preprocessing23.RDP’s naive Bayesian classifier was applied on representative RSVs for taxonomy assignment against SILVA SSU Ref NR dataset v.132 at 99% sequence similarity24. The core genus in our dataset was defined as the genus that was detected in 80% of all samples, while the core genus for each study group was defined as the genus that was present in all samples of this group.Bacterial diversity was estimated using QIIME2 on the entire dataset without subsampling. Alpha diversity was determined using two approaches; regarding richness (number of observed species and Chao1 index) and evenness of communities (Shannon diversity index). The statistical significance of pairwise comparisons was assessed using unpaired Wilcoxon rank sum test, while multiple group comparisons were estimated using Kruskal–Wallis rank sum test and all P values were corrected using false discovery rate method (FDR)25. Similarity distances between cutaneous microbiomes were visualized by principal coordinates analysis (PCoA) based on weighted UniFrac distance matrix. Permutational Multivariate Analysis of Variance  was applied to define the significance of weighted UniFrac distance-based clustering of samples26.Phylogenetic relatedness of bacterial communities was identified using both unweighted and weighted UniFrac matrices27.To determine the dermotypes of cutaneous microbiomes, a widely used enterotyping pipeline was applied to all genera in our dataset. Clustering of samples and the optimum number of clusters were achieved using partitioning around medoids (PAM) algorithm, Jensen–Shannon divergence (JSD) and Calinski-Harabasz (CH) index28 against Greengenes database (V 13.8)29 at a 97% identity using closed-reference script for OTU picking in QIIME, v 1.9.129. Functional potential of cutaneous microbiomes was predicted using Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) for mapping the Kyoto Encyclopedia of Genes and Genome (KEGG) Orthology (KO) Database at level 332. LEfSe was applied to the metagenomic data to define the taxon or metabolic pathway (logarithmic LDA scores > 3.0 and α = 0.05) that were differentially abundant among healthy subjects and patients with RID (https://huttenhower.sph.harvard.edu/lefse/)33.For predicting the functional profile of cutaneous microbiota, representative RSVs were employed for further taxonomic classification using UCLUSTP ≤ 0. 01) using R package, Hamsic34. R packages; Phyloseq and ggpubr, were applied for calculation and plotting of diversity indices (https://rpkgs.datanovia.com/ggpubr/)36, while ggplot2 was used for graphical illustrations of results 37.Correlations between either communities’ members or structure of microbiota and patient’s clinical data were defined by Spearman correlation coefficient  and biosamples (SAMN168624511: SAMN16862528).16S rRNA row reads of this study have been deposited in NCBI bioproject under accession number PRJNA665254 (Ninety-eight subjects were included in this study (20 controls and 78 patients with RID). Patients’ data regarding clinical characteristics, demography and outcome were listed in Table In total, 11,276,243 row sequences  were inputted in Qiime2 for merging, quality checking, removal of low quality reads  and potential chimeric sequences  that were resulted in 9,283,731high quality sequences that were used for downstream analyses.P = 2.58 × 10–7: Spearman; r = -0.68, P = 0.001) . In contrast, microbiomes of chronic ulcers were significantly predominated by Proteobacteria and low abundance of Firmicutes .16S rRNA reads were taxonomically assigned to 19 phyla, 58 classes, 109 orders, 237 families, 658 genera and 4643 OTUs. In total, cutaneous microbiomes associated to RID showed a remarkable representation of certain bacterial taxa at different taxonomic levels that was in contrast to healthy subjects  . Cutaneous microbiomes of RID that turned to chronic ulcer had significantly reduced bacterial diversity in comparison to either healthy individuals or rapidly healed RID .Identification of bacterial diversity associated with RID was performed using both evenness and richness indices. Skin microbiomes of healthy subjects were significantly more diverse than those with RID (Wilcoxon test: –5) Fig. . SurprisBoth structure and composition of bacterial communities significantly drove the classification of cutaneous microbiomes to health-state based clustering Fig. a. PCoA bEnterobacteriaceae or Staphylococcaceae were the most predominant families in several RID specimens, while genus level analysis was provided a clear separation of genera belonging to the previous families .Studying the structure of RID microbiomes at the family level unable to provide a deep understanding of the potential causative agent of RID. For instance, either ies Fig. a. In genKlebsiella, Pseudomonas, Cutibacterium, Corynebacterium, Bacillus and uncultured Enterobacteriaceae were detected in all samples with variable abundance . Additionally, the predominance of these species was accompanied by a slightly enriched representation of uncultured Enterobacteriaceae species, Klebsiella varicola, Stenotrophomonas maltophilia, Rothia dentocariosa and Acinetobacter johnsonii. Nevertheless, unclassified sequences represented about 21.83% of cutaneous microbiomes of controls, while in RID microbiomes they were constituted 1.69%. Strikingly, K. pneumoniae was negatively correlated to P. aeruginosa in all study groups . Also, the strongest correlations were detected between P. aeruginosa, S. aureus and S. maltophilia.Species level analysis of RSVs revealed the significant enrichment of The collective metabolic functional profile of RID microbiome was significantly associated with the overrepresentation of metabolic pathways that could be attributed to impairments in epidermal integrity, alteration in pH and supporting microbial survival such as lipid metabolism, histidine metabolism, enhanced bacterial invasion of epithelial cells, signaling molecules of bacterial toxins, hedgehog signaling pathway, nitrogen metabolism and peptidases . Diabetes mellitus is a metabolic disorder that is significantly linked to developing chronic wounds due to the impairments in wound healing phases that provides favorable conditions for either opportunistic residents or pathogenic bacteria50. Also, colonization of wounds with certain microorganisms was strongly correlated to the persistence of wound via organism induced body changes that include epidermal barrier integrity, alteration in pH and dysregulation of the immune system53. Overall, developing chronic ulcer in diabetic patients with RID could potentially depend on the colonizing microorganisms through intensifying the epidermal disturbances produced by diabetes mellitus.One of the interesting findings is the significant association between diabetes mellitus and developing a chronic ulcer in RID patients (Spearman: r = 0.86; Klebsiella genus was inversely correlated to other predominant genera in all datasets, Pseudomonas, Staphylococcus and Stenotrophomonas have exhibited a significant coexistence especially in prolonged RID and chronic ulcers (Supplemental Table S. aureus and P. aeruginosa on the clinical outcome of cystic fibrosis is controversial, the comparisons with mono-infection of S. aureus or P. aeruginosa showed that the pair coexisting was significantly associated with prolonged hospitalization and exacerbation of the disease54. Also, the bidirectional interplay between this pair was manifested in the inhibition of phagocytosis, in addition to the promotion of staphylococcal biofilm formation by P. aeruginosa55. Additionally, Stenotrophomonas maltophilia was detected in our samples with significant prevalence especially in RID patients. S. maltophilia has emerged as an opportunistic pathogen with global concerns, due to its significant association with the high crude mortality in pneumonia and bacteremia of immunosuppressed patients56. S. maltophilia was also reported to cause wound infections, soft tissue infections, bone and joint infections, and cellulitis58. Interestingly, in our study, the coexistence of S. maltophilia and P. aeruginosa was strongly correlated to develop chronic ulcers in RID. This observation was in agreement with the previously reported cooperative pathogenicity of this pair in cystic fibrosis59.The main interesting finding of the present study is the collective correlations between community members. While Staphylococcus genus was defined as a core genus in healthy and diseased groups. Although S. aureus was significantly enriched in RID microbiomes, it was overrepresented in the rapidly healed RID. These findings were matched with the previous study which reported that the S. aureus infection was conjugated with limited exacerbations and a short duration of hospitalization54.As expected in the cutaneous microbiome, K. pneumoniae showed fluctuated representation in our specimens. In microbiomes of RID, K. pneumoniae was significantly overrepresented especially in samples that turned to a chronic ulcer, and its abundance was strongly linked to diabetes mellitus. As it is known that K. pneumoniae have been implicated in liver abscess, meningitis and psoas abscess60. Furthermore, K. pneumoniae may harbor diverse virulence characteristics including capsules, multidrug resistance and virulence factors that enhance invasion and promote epidermal deteriorations62. The coexistence of these characteristics and diabetes mellitus could boost epidermal damage, aggravate the inflammatory processes and retard the repair of the epidermal barrier.Notably, The limitations of this study are the slightly small sample size of each group, dependence on unculturable approach, lack of microbiome characterization at different sampling time and isolation of causative agents in order to define their virulence characteristics including antimicrobial resistance patterns.Klebsiella or coexistence of Pseudomonas, Staphylococcus and Stenotrophomonas potentially prompt the chronic ulcer formation in RID patients. Cutaneous microbiome profiling at the early stages of RID could be indicative of the prospective clinical outcomes and might be a helpful guide for personalized therapy and management of RID. Finally, shifts in the structure and prevalence of cutaneous microbiota that accompany the RID could support the candidate role of microbial dysbiosis in the pathogenesis of RID.We have studied the microbiome of patients with RID in order to accentuate the underlying bacterial structure and to provide new insight about the potential role of microbiota as an influential factor in pathogenesis and clinical outcome of RID as well. A notable positive correlation has existed between bacterial diversity and recovery rates of RID. The overwhelming predominance of Supplementary Information.


Neurofascin mRNA, encoding the cell adhesion molecule essential for paranode assembly and maintenance. Loss of TDP-43 triggers the retention of a previously unidentified cryptic exon, which targets Neurofascin mRNA for nonsense-mediated decay. Thus, TDP-43 is required for neurofascin expression, proper assembly and maintenance of paranodes, and rapid saltatory conduction. Our findings provide a framework and mechanism for how Schwann cell-autonomous dysfunction in nerve conduction is directly caused by TDP-43 loss-of-function.TDP-43 is extensively studied in neurons in physiological and pathological contexts. However, emerging evidence indicates that glial cells are also reliant on TDP-43 function. We demonstrate that deletion of TDP-43 in Schwann cells results in a dramatic delay in peripheral nerve conduction causing significant motor deficits in mice, which is directly attributed to the absence of paranodal axoglial junctions. By contrast, paranodes in the central nervous system are unaltered in oligodendrocytes lacking TDP-43. Mechanistically, TDP-43 binds directly to  Tardbp) is a nucleic acid-binding protein that regulates the processing of a wide range of coding and noncoding RNAs by directly binding to transcripts and/or interacting with key RNA-processing complexes , which encodes a glial cell adhesion molecule necessary for paranodal junction formation and maintenance, by repressing the usage of a cryptic exon during splicing. Our findings are the first demonstration of a functional role for TDP-43 in axon–glial interactions in the PNS and that the loss of function for TDP-43 in Schwann cells results in impaired conduction velocity and motor behavior.Not surprisingly, the function of TDP-43 is mainly focused in neurons . Howeverfl/flTardbp)   with Dhh channels and their associated protein complex from juxtaparanodal regions to paranodes  do not exhibit a gross neurological deficit when observed in their home cage. However, when challenged with the rotarod test, the cKO mice perform significantly worse than WT littermates . Intriguingly, when the sequencing reads are aligned to the Nfasc locus and analyzed, we find reads mapped to introns 17 and 18 of Nfasc. Because intron 17 contains a UG-rich sequence, a known consensus RNA-binding motif for TDP-43 . At 3 months post-tamoxifen injection, NFasc is absent from a similar proportion of Schmidt–Lanterman incisures in the sciatic nerves and ventral roots  . While Nnn cells . The pronn cells , suggestNfasc gene, which overlaps with TDP-43-binding sites. Schwann cell NFasc protein is known to be essential for paranodal junction assembly and maintenance  is highly enriched at the axon initial segments and nodes and is required for maintaining the high density of Nav channels therein  (Cnp-Cre (-/-Cntnap1 (Caspr KO) (Mpz-CreERT2 (P0-CreERT2)    ; Mpz-CreCreERT2) . All expThe following primary antibodies were used: mouse anti-actin , mouse anti-AnkB , mouse anti-AnkG , mouse anti-AnkG , mouse anti-βII spectrin , chicken anti-βIV spectrin (a gift from Dr. Matthew N. Rasband), rabbit anti-βIV spectrin , mouse anti-Caspr (Mab275) , rabbit The sciatic nerves, trigeminal nerves, and spinal cords were either dissected after transcardial perfusion and postfixed as described previously  or freshAfter air dried, the tissues on the coverslips were blocked with 10% (v/v) normal goat or donkey serum, 0.3% (v/v) Triton X-100 in PBS for 30 min, and stained with primary antibodies diluted in the blocking solution at 4°C overnight. After one wash with the blocking solution and two washes with PBS for 5 min each, the tissues were stained with secondary antibodies diluted in the blocking solution at room temperature for 1 hr. After one wash with the blocking solution and two washes with PBS, the coverslips were mounted onto glass slides in Vectashield Vibrance mountant (Vector Laboratories) or ProLong Diamond mountant (Thermo Fisher Scientific).Nerve conduction studies were performed as described previously with modification . In brieAfter sacrificing the mice, the sciatic nerves were exposed and the lower bodies of the mice were fixed in 4% (w/v) PFA, 2.5% (w/v) glutaraldehyde in 0.1 M sodium cacodylate, 5 mM calcium chloride, pH 7.4 at room temperature overnight, and at 4°C for 2 days. Nerves were dissected and stored in the same fixative at 4°C for at least 2 days. Nerves were then processed as previously described  and wereFour-week-old mice were first familiarized with the rotarod (Ugo Basile 47600 V04) at 4 rpm for 5 min. Thirty minutes later, the mice were challenged with accelerating rotarod from 4 to 40 rpm within 5 min for three trials, separated by 30 min. The next day, the mice were tested with the rotation speed increased from 4 rpm to 24 or 32 rpm within 30 s and maintained at 24 or 32 rpm, respectively, for another 60 s. Three trials were performed for each speed, and the mice were allowed to rest for at least 10 min between trials. The time periods for which each mouse remained on the rotarod at each speed were recorded and averaged.Sciatic nerves were homogenized with sonication in 320 mM sucrose, 5 mM sodium phosphate (pH 7.2), 0.2 mM sodium fluoride, 0.2 mM sodium orthovanadate, 1× cOmplete protease inhibitor cocktail (Roche), and 1 mM phenylmethylsulfonyl fluoride on ice. The protein concentration was determined with the BCA protein assay kit (Thermo Fisher Scientific) using the standard curve derived from a serial dilution of bovine serum albumin; 30 μg of total protein was subjected to western blotting.g for 15 min at 4°C. The total RNA was purified from the supernatant using the Direct-zol RNA Miniprep kit (Zymo Research) by following the manufacturer’s instruction including the in-column DNase I treatment. 0.5 μg of total RNA (concentration determined by the absorbance at 260 nm) was used in 20 μl of reverse transcription reaction with LunaScript RT SuperMix (New England Biolabs) and its No-RT Control Mix according to the manufacturer’s instruction. The RT and No-RT reactions were then diluted to 1/4× with deionized water, and 2 μl was used for qPCR in 25 μl of reaction containing 0.5 μM primers with Power SYBR Green PCR Master Mix and QuantStudio 3 Real-Time PCR System (Thermo Fisher Scientific). The thermocycling parameters are 95°C for 10 min, and 40 cycles of 95°C for 15 s and 60°C for 1 min, followed by melting curve analysis. The primers used in qPCR are as follows (from 5′ to 3′): Tardbp ex3 , Tardbp ex4-5 , pan Nfasc , NF155 , NF140+ex27 , NF140-ex27 , G6pdx , and Polr2a . Polr2a was chosen as the reference gene . The efficiency of each primer pair was validated to be between 90% and 110% with six points of threefold or fourfold serial dilutions of P16 mouse sciatic nerve cDNAs or P31 mouse spinal cord cDNAs. The primer specificity was screened on the Ensembl genome browser by using the BLASTN search tool against the cDNA database and genomic sequence, and confirmed by gel electrophoresis and sequencing from both ends of the PCR products. Technical triplicates of the RT reaction and duplicates of the No-RT reaction were performed for each biological replicate, and three biological replicates were analyzed. The relative transcript level was calculated by the ΔΔCq method. Comparison of cHet or cKO with WT was carried out by one-sample unpaired two-tailed t-tests with the test mean equal to 1.Sciatic nerves were homogenized in the TRIzol reagent (Thermo Fisher Scientific) using a Dounce homogenizer (Wheaton) and incubated at room temperature for 5 min. The homogenate was extracted with chloroform, incubated at room temperature for 3 min, and centrifuged at 12,000×nce gene , and theNfasc gene spanning exons 17 and 20 were (from 5′ to 3′): GCAAAGGCCTACCTCACTGT (forward) and CTCGTTGACAGCGATGACTC (reverse). Similar results were also obtained by using GACCAGGGCAGTTACACG  and TCACACTCCTCTCAGCCAG . The PCR products were resolved in agarose gel.Total RNA was extracted from sciatic nerves and spinal cords using the TRIzol reagent according to manufacturer’s instruction. After DNase treatment using RQ1 RNase-Free DNase (Promega), 0.5–1 μg of RNA was reverse transcribed using Maxima First Strand cDNA Synthesis Kit for RT-qPCR (Thermo Fisher Scientific) and subsequently used for PCR. Primers for mouse fl/flTardbp, fl/+Cnp-Cre;Tardbp, and fl/flCnp-Cre;Tardbp mice (n = 3 per genotype) were used to prepare RNA-seq libraries using the TruSeq RNA Sample Prep Kit (Illumina). Illumina HiSeq4000 was used for paired-end 151 bp sequencing and yielded 30–40 million reads per sample. This data has been deposited in NCBI's Gene Expression Omnibus . The data points of five or less were assumed to be drawn from normal distributions. For the ANOVA tests, homogeneity of variance was not rejected by Levene’s tests. Biological replication is achieved by analyzing different mice. Technical replication is achieved by repeating the experiments using the same samples. The number of mice or technical replicates used for each comparison is described in the figure legends and Materials and methods. No data points were excluded except that one WT mouse in the rotarod test was considered an outlier, which may have learned that the consequences of falling are innocuous  is reduced, while the neuronal splice form encoding NF186 is unaltered. While it is likely that TDP-43 affects additional transcripts in Schwann cells, this study reveals one key protein that is altered as a consequence of TDP-43 deletion. As loss of TDP-43 function is associated with numerous disease and injury states, the studies have important implications for the consequences of these changes in Schwann cells.During development, selective deletion of TDP-43 from Schwann cells revealed a cell-autonomous function in paranodal junction assembly and motor nerve conduction, but not formation of compact myelin. Mechanistic studies identified that the production of the glia-specific splice form of Decision letter after peer review:eLife. Your article has been reviewed by three peer reviewers, and the evaluation has been overseen by a Reviewing Editor and Gary Westbrook as the Senior Editor. The following individuals involved in review of your submission have agreed to reveal their identity: Roman Giger (Reviewer #1); James Salzer (Reviewer #2); Phil Wong (Reviewer #3). The reviewers have discussed the reviews with one another and the Reviewing Editor has drafted this decision to help you prepare a revised submission.Thank you for submitting your article "TDP-43 maximizes nerve conduction velocity by repressing a cryptic exon for paranodal junction assembly in Schwann cells" for consideration by eLife papers without additional data, even if they feel that they would make the manuscript stronger. Thus the revisions requested below only address clarity and presentation.We would like to draw your attention to changes in our revision policy that we have made in response to COVID-19 (https://elifesciences.org/articles/57162). Specifically, we are asking editors to accept without delay manuscripts, like yours, that they judge can stand as Summary:Nfasc mRNA  results in a premature stop codon, triggering nonsense-mediated decay of its mRNA. The absence of this protein provides an explanation for the altered assembly of paranodal junctions, the marked delay in peripheral nerve conduction and associated motor discoordination. Nuclear exclusion of TDP-43 occurs in many cell types following injury and progressive disease, raising the possibility that Schwann cell dysfunction may also contribute to pathological changes during these conditions.This study describes the consequences of selective deletion of the of the RNA binding protein TDP-43 from Schwann cells. Using in vivo genetic manipulations in mice, the authors show that TDP-43 is required for both the formation and maintenance of paranodal junctions in the peripheral nervous system. TDP-43 is known to suppress the incorporation of cryptic exons in diverse mRNAs. In Schwann cells lacking TDP-43 they find that inclusion of a cryptic exon in Essential revisions:1) Provide information about the characteristics of axons and myelin in the Tardbp cko mice . Changes in these features could also affect conduction velocities and contribute to paranodal defects. This is particularly important, given the large number of potential mRNA targets of TDP-43 and the observation that myelination is delayed in the conditional mutants, a phenomenon not normally observed in paranodal mutants. If this analysis is not possible in a reasonable time frame, please describe in detail the observations that can be made from existing electron micrographs and revise the text to discuss how alterations in other aspects of these myelinated nerves could contribute to the phenotypes exhibited by the Tardbp cKO mice.2) Revise Figure 1. It is difficult to appreciate that TDP-43 is present in normal Schwann cells without displaying the Sox10 channel alone. Quantification of overlap should be provided, along with evidence that nuclear TDP-43 in non-Schwann cells was not affected by this manipulation. In Figure 1A it appears that Sox10 is strongly upregulated in cKO nerves. If this is the case, provide quantification, if not, replace figure panel with a more representative example (or single channel images). Dhh-Cre is active in endoneurial fibroblast precursors , so it is unclear what cell type persistently express TDP43 in the P28 Dhh-Cre cKOs. The quality of the images of isolated nerves in panel D could be improved.3) Revise the discussion of TDP-43 splicing repression in human Schwann cells. The lack of conservation between cryptic exons between species make this hypothesis very speculative. It would enhance the impact of the study to search available databases for evidence in humans of TDP-43 targets related to paranodal junction genes. Such human data would provide strong clinical implications of findings from this manuscript. It is possible that other TDP-43 targets related to paranodal junction are impacted in ALS patients. However, inclusion of these data is not deemed necessary for publication.4) Revise Figure 2. Figure 2H: In assessing behavioral outcomes of TDP-43 cKO mice, a mild defect in rotarod test was observed and it appeared that there is a bimodal distribution where one group of mice show a deficit whereas the other group seemed normal. Can this be explained by extent of neurofascin cryptic exon inclusion or gender of mice? Is there assessment using an independent behavioral task to confirm this finding? Given the non-normal distribution, a standard t-test is not appropriate for this statistical comparison. Essential revisions:1) Provide information about the characteristics of axons and myelin in the Tardbp cko mice . Changes in these features could also affect conduction velocities and contribute to paranodal defects. This is particularly important, given the large number of potential mRNA targets of TDP-43 and the observation that myelination is delayed in the conditional mutants, a phenomenon not normally observed in paranodal mutants. If this analysis is not possible in a reasonable time frame, please describe in detail the observations that can be made from existing electron micrographs and revise the text to discuss how alterations in other aspects of these myelinated nerves could contribute to the phenotypes exhibited by the Tardbp cKO mice.t test). The myelin thickness of the WT and cKO is comparable and does not contribute to the conduction delay along the cKO nerves. We find that the myelinated axons in the cKO tend to have smaller diameters; however, because the absence of paranodal junctions is known to cause ~40-50% conduction delay , and we observed a 52% delay in the TDP-43 cKO, we believe that the smaller axon diameter in the cKO only contributes to a small portion in the delay of nerve conduction. We have revised the manuscript to discuss this variable.We want to thank the reviewer for this important comment, as it constitutes an alternative conclusion. We have now measured the g-ratios and axon diameters from sciatic nerves of three WT and three cKO mice at P21, and the data is now presented in Figure 1—figure supplement 2. The g-ratios between the WT and cKO mice are not statistically different (p = 0.1214 by 2) Revise Figure 1. It is difficult to appreciate that TDP-43 is present in normal Schwann cells without displaying the Sox10 channel alone. Quantification of overlap should be provided, along with evidence that nuclear TDP-43 in non-Schwann cells was not affected by this manipulation. In Figure 1A it appears that Sox10 is strongly upregulated in cKO nerves. If this is the case, provide quantification, if not, replace figure panel with a more representative example (or single channel images). Dhh-Cre is active in endoneurial fibroblast precursors , so it is unclear what cell type persistently express TDP43 in the P28 Dhh-Cre cKOs. The quality of the images of isolated nerves in panel D could be improved.We now include the single-channel images for TDP-43 and Sox10 from P28 in Figure 1—figure supplement 1, together with those from P3. All the Sox10-positive nuclei are TDP-43-positive in the WT. The intensity of Sox10 staining varies among different nuclei of the WT and cKO especially at P28, and we did not observe a change in the Sox10 levels in the cKO.We thank the reviewers for bringing our attention to the study by Joseph et al., 2004. We observed the complete loss of paranodal junctions in the PNS using three different Cre driver lines to conditionally knock out TDP-43 in our study—Dhh-Cre, P0-Cre and Cnp-Cre—and this strongly indicates that the phenotype we observe is cell-autonomous to Schwann cells. Furthermore, we have stained the endoneurial fibroblasts with PDGFRα and confirmed that the fibroblasts are among the TDP-43-positive/Sox10-negative population in the cKO mice (by Dhh-Cre), which includes other PDGFRα-negative, non-fibroblast cells as well . The apparent discrepancy between our observation and that of Joseph et al. with the Dhh-Cre in endoneurial fibroblasts may be attributed to the different floxed alleles involved. This has been shown to be the case for Cnp-Cre . In brief, when combining the Tardbp floxed allele and Dhh-Cre, we do not observe recombination in endoneurial fibroblasts.We have changed panel D of Figure 1 to improve the picture quality.3) Revise the discussion of TDP-43 splicing repression in human Schwann cells. The lack of conservation between cryptic exons between species make this hypothesis very speculative. It would enhance the impact of the study to search available databases for evidence in humans of TDP-43 targets related to paranodal junction genes. Such human data would provide strong clinical implications of findings from this manuscript. It is possible that other TDP-43 targets related to paranodal junction are impacted in ALS patients. However, inclusion of these data is not deemed necessary for publication.NFASC pre-mRNA  Revise Figure 2. Figure 2H: In assessing behavioral outcomes of TDP-43 cKO mice, a mild defect in rotarod test was observed and it appeared that there is a bimodal distribution where one group of mice show a deficit whereas the other group seemed normal. Can this be explained by extent of neurofascin cryptic exon inclusion or gender of mice? Is there assessment using an independent behavioral task to confirm this finding? Given the non-normal distribution, a standard t-test is not appropriate for this statistical comparison.The complete loss of paranodal junctions has been confirmed in at least two cKO mice per Cre driver line , and the paranodal phenotype has a 100% penetrance. We have included more mice in the rotarod analysis for a total of 10 mice per genotype. The cKO data points are now more evenly distributed , and the normality of the data point distribution is not rejected by the Shapiro-Wilk test (p = 0.1513 for 24 rpm and p = 0.1949 for 32 rpm). The majority of the WT mice could remain on the rotating rod until the cutoff time of 90 sec and indeed the normality of the WT distribution is rejected by the Shapiro-Wilk test. Therefore, we have switched to the Mann-Whitney statistical analysis and now present the data in box-and-whisker plots. The motor deficit of the cKO mice is now confirmed with a larger group of mice and by using the Mann-Whitney test (p = 0.0115 for 24 rpm and p = 0.0036 for 32 rpm). We have revised the manuscript and source data file accordingly.


AlGaN/GaN fin-shaped field-effect transistors (finFETs) with a graphene gate were fabricated and studied. These devices demonstrated ~8 order of magnitude on/off ratio, subthreshold slope of ~1.3, and low subthreshold current in the sub-picoamperes range. The effective trap density responsible for the 1/f low-frequency noise was found within the range of (1–5) · 1019 eV−1 cm−3. These values are of the same order of magnitude as reported earlier and in AlGaN/GaN transistors with Ni/Au Schottky gate studied as a reference in the current study. A good quality of graphene/AlGaN Schottky barrier diodes and AlGaN/GaN transistors opens the way for transparent GaN-based electronics and GaN-based devices exploring vertical electron transport in graphene.Electrical and noise properties of graphene contacts to AlGaN/GaN heterostructures were studied experimentally. It was found that graphene on AlGaN forms a high-quality Schottky barrier with the barrier height dependent on the bias. The apparent barrier heights for this kind of Schottky diode were found to be relatively high, varying within the range of φ The invention of graphene opened the road to new exciting physics and new devices based on the unique ultimate geometry of graphene and its specific physical properties and effects. Among them are extremely high carrier mobility ,2,3, quaThe majority of the graphene research deals with in-plane  current transport. A much less explored field is vertical transport through graphene and other two-dimensional materials. Indeed, there are just a few fields of research activity in this direction: transparent electrodes for light-emitting diodes and displays , verticaAnother promising field, which is the topic of the current letter, is graphene electrodes for electronic devices. It is known that graphene can form either an ohmic or Schottky barrier contact to semiconductors (see Reference  and refeThe combination of graphene on the top of the AlGaN layer in AlGaN/GaN high-electron-mobility transistors (HEMTs) and 2D electron gas (2DEG) on AlGaN/GaN interface create a unique system with two closely spaced high-conductivity 2D layers. This kind of system is a promising platform to study the Coulomb interactions  and two-Although graphene/AlGaN/GaN heterostructures are promising for several applications, the properties of them are only preliminary studied.In this work, we studied the properties of the graphene for AlGaN contact and the behavior of AlGaN/GaN finFETs with the graphene Schottky barrier gate. Special attention was paid to the low-frequency noise properties, which characterize the quality of the structures and are crucial for the majority of applications.0.15Ga0.85N barrier layer, 2.7 μm intentionally undoped GaN layers, and 100 nm Al0.03Ga0.97N buffer. The schematic of the layer sequence and qualitative band diagram of the structure are shown in The AlGaN/GaN structures were grown by the Metalorganic Vapour Phase Epitaxy method in the closed coupled showerhead 3 · 2 inch Aixtron reactor . The epistructure consisted of 2 nm GaN cap, 25 nm AlThe device processing was performed using a commercial laser writer system  for lithography processing with the 405 nm GaN laser source. In order to separate devices on the wafer, the shallow 150 nm mesas were etched using Inductively Coupled Plasma-Reactive Ion Etching (ICP-RIE)    starting from the edge of the stack. As a result, Gr/PMMA separated from Cu foil and remained floating on the electrolyte surface. After that, the detached Gr/PMMA stack was moved to deionized water to rinse the electrolyte residue, transferred onto AlGaN/GaN structure, and heated at ~130 °C to make better contact. Finally, the PMMA support was carefully removed in acetone, and the structure with graphene was rinsed in IPA. This procedure allowed us graphene deposition on large area substrates of 1 inch or more in diameter. Measurements of the back-gate transistors fabricated using this graphene indicated its p-type. We used a commercially available single-layer graphene  produced by chemical vapor deposition (CVD) method on the surface of thin copper foils . The ste−1), 2D (2680 cm−1), and D (1350 cm−1). Low Full Width at Half Maximum (FWHM about 32 cm−1) of the 2D peak, as well as a much higher intensity of the 2D mode by comparison with the intensity of the G peak (2D/G > 2) are characteristic of the monolayer of graphene. Very low D mode amplitude indicates the high quality of the graphene structures. After high-speed electrochemical delamination, graphene was patterned in oxygen plasma using an Oxford Instruments Plasmalab 80 Plus ICP-RIE system .The quality of the graphene layers was controlled with Raman spectroscopy and Scanning Electron Microscopy (SEM). The surface morphology of the transferred graphene samples was investigated by Auriga CrossBeam Workstation (Carl Zeiss) . As a result of the etching, graphene remained on the mesas leaving the short ends of the rectangular mesas free from it. These parts of the mesas were used to fabricate ohmic contacts to 2DEG. In order to form ohmic contacts, Ti/Al/Ni/Au (150/1000/400/500 Å) layers were deposited and rapid thermal annealed at 800 °C in the nitrogen atmosphere for 60 s. Parts of the graphene remained out of the mesas on GaN buffer and were used to fabricate Cr/Au (50/1850 Å) ohmic contacts to it. The resulting design represents finFET with the graphene gate. This design allowed us to study the properties of the graphene AlGaN Schottky barrier and the characteristics of the finFETs themselves.g = 5–20 µm and Wg = 4–20 µm, respectively. As a reference, finFETs with standard Ni/Au (250/750 Å) Schottky barrier gates were also fabricated.The schematic view of the fabricated finFET and optical microscope image of one of the graphene gate transistors are shown in v is the drain voltage fluctuations and Rd is the differential device resistance.All measurements were done at room temperature using a probe station. The spectral noise density of drain current fluctuations was calculated as g). In accordance with the thermionic emission (TE) model, the current–voltage characteristic of the Schottky diode at B is the Boltzmann constant, T is the temperature, A* is the modified Richardson constant, S is the contact area, and φb is the barrier height. Although under the TE model the ideality factor n = 1, experimental characteristics are always characterized by n > 1. The higher than unity ideality factor can be attributed to the effects of image force barrier lowering and the non-idealities of the barrier, such as inhomogeneity of the barrier height and the contribution of other current mechanisms . Therefore, the ideality factor is often used as a figure of merit of the barrier quality. The current-voltage characteristic of Au/Ni/AlGaN Schottky barrier diode in As seen, the Au/Ni/AlGaN Schottky barrier diode demonstrates exponential forward current–voltage characteristics I–exp  eV for all studied diodes. The apparent barrier heights for the graphene/AlGaN diode in b = (1.0–1.26) eV.Equation (1) allows us to estimate the saturation current and the barrier height. However, the ideality factor n > 1 is an indication of the non-ideality of the barrier. Therefore, the barrier height for the diodes with the ideality factor significantly higher than unity should be considered only as an apparent barrier height. We found φThe barrier height for Ni/AlGaN Schottky barrier reported in the publications is within the range of (0.85–0.99) eV  at frequency f = 10 Hz for three representative graphene gate transistors are shown in The dependences of the relative spectral noise density t is the effective trap density, s is the concentration, and γ is the attenuation coefficient of the electron wave function under the barrier:In the McWhorter model, the spectral noise density of the drain current fluctuations given by :(2)SII2=8 cm−1. For the AlGaN/GaN system, the attenuation coefficient is somewhat smaller: γ ≅ 0.45 × 108 cm−1 [Here m* is the electron effective mass, h is the Planck’s constant, and Φ is the tunneling barrier height at the interface. In Si MOSFETs, the γ value is usually taken to be γ = 10108 cm−1 .s ~ (Vg − Vt), the McWhorter model predicts the dependence of noise on the gate voltage as t on energy (gate voltage). As seen in Since in the linear regime nferences ,25). Them is the external transconductance, q is the electron charge, and C is the gate capacitance per unit area. This method allows us to get rid of the uncertainty of the threshold voltage and take into account the possible influence of the contact resistance [The effective trap density can be also found from the input gate voltage noisesistance .g. This effect can be due to the dependence of the trap density on the energy. At high gate voltage, the trap density is close to 1019 eV−1 cm−3. Similar or higher values of the effective trap density within the range of (1018–1020) eV−1 cm−3 were found in the majority of publications on Si MOSFETs with a high-k dielectric (see References [t ≅ 1017 eV−1 cm−3 [t = (1018–1020) eV−1 cm−3 (see t = (2.3 × 1019–1.7 × 1020) eV−1 cm−3 in AlGaN/GaN HEMT structures with Ni/Au gate.One can see that the effective trap density for studied devices only weakly depends on the gate voltage, reflecting the ferences ,29,30,312O or O2 plasma oxidation treatment of AlGaN surface strongly increases the noise. On the other hand, AlGaN/GaN transistors with insulated Al2O3 or SiO2 gate have shown to have lower noise [Although AlGaN/Schottky barrier interface is relatively far from the two-dimensional channel, it is known that this interface still may affect the noise originated from the channel. In Reference , it was er noise . Therefob = (1.0–1.26) eV. The relatively high value of the apparent barrier height in comparison with other published results is an indication of low defect concentration in AlGaN and good quality of the interface. AlGaN/GaN finFETs demonstrated good characteristics with ~8 order of magnitude on/off ratio and subthreshold slope of ~1.3. The effective trap density found from the low-frequency noise measurements was ≥1019 eV−1 cm−3, which is of the same order of magnitude as in the transistors with Ni/Au Schottky gate. This is an indication that graphene forms a high-quality Schottky barrier to AlGaN which can serve as a gate for various types of transistors. It is important that the open surface of graphene does not deteriorate electrical and noise properties of 2D gas on the AlGaN/GaN interface. These results pave the way towards transparent high-temperature GaN-based electronics and to study Coulomb interactions in the graphene/AlGaN/GaN system.In summary, we fabricated and studied graphene gate AlGaN/GaN finFETs. Study of the vertical transport in graphene/AlGaN Schottky diodes indicated the dependence of the Schottky barrier on the bias. The apparent barrier heights for the graphene/AlGaN diodes were found to be within the range of φ


Giant cell myocarditis (GCM) is a rare and rapidly fatal cardiovascular condition most often seen in young adults. It is characterized microscopically by myocardial necrosis with multinucleated giant cells in the absence of well-defined granulomas. This disorder has typically been attributed to manifest as heart failure, but in some individuals, GCM may present as sudden cardiac death. Herein, we present a fatal case of GCM in a 36-year-old male with a history of autoimmune disorders. The decedent presented to the emergency room due to vomiting and was treated for nausea due to suspected dehydration. He was discharged that night and found dead on his bathroom floor the following day. Postmortem examination revealed psoriasis and granulomatous lesions in the lungs consistent with sarcoidosis, further supporting circumstantial evidence existing between GCM and autoimmune disorders. Additionally, this case provides an opportunity to distinguish GCM from the distinct clinical entity of cardiac sarcoidosis (CS), especially in the setting of systemic sarcoidosis. We hope to raise awareness of this rare disease process and its potential to cause sudden cardiac death so that it may be considered in a differential diagnosis as immunosuppression and early cardiac transplantation largely determine the prognosis. Giant cell myocarditis (GCM), commonly referred to as idiopathic giant cell myocarditis (IGCM), is a rare disorder that typically affects young to middle-aged adults that was first described in 1905 as a mixed myocardial infiltrate with multinucleated giant cells and cardiomyocyte necrosis.,Giant cell myocarditis is extremely rare with less than 300 reported cases since its initial distinction from myocarditis in 1905,Herein, we present a case of SCD due to GCM in a patient also found to have probable pulmonary sarcoidosis with the goal of increasing our understanding of the defining characteristics, presentation, distinction, and etiology of GCM along with exploring the relationship of GCM with sarcoidosis and other autoimmune diseases.A 36-year-old white male who reported not feeling well was seen at the local emergency room for nausea and vomiting due to suspected dehydration. He was given intravenous fluids, ondansetron, and metoclopramide and then deemed stable for discharge. He was also prescribed promethazine for nausea and was instructed to continue taking his home medications, which included halobetasol, lisdexamfetamine, and sertraline. He was found unresponsive on his bathroom floor by his mother the following afternoon and death was pronounced that evening. The autopsy was performed the following morning. Access to previous encounters was not available.The decedent’s external examination was largely unremarkable, showing a well-developed, well-nourished, adult Caucasian male who weighed 75.8 kilograms and was 1.70 meters in height. Pink, scaly skin covered the extensor surfaces of his upper and lower extremities, consistent with his clinical history of psoriasis.The heart weighed 510 grams  and was otherwise unremarkable externally. Upon sectioning, the myocardium was dark, red-brown, and firm with multiple areas of yellow-tan discoloration involving both ventricles and extending from apex to base . These aThree sections were taken for microscopic examination, and revealed geographic replacement of myocardium by confluent areas of central fibrosis and necrosis with scattered multinucleate giant cells and a leading edge with a mixed inflammatory infiltrate with lymphocytes, plasma cells, eosinophils, and giant cells with associated myocyte necrosis 22C. AddiThe right and left lungs weighed 790 and 830 grams respectively  and were found to be edematous grossly. The upper and lower airways were patent, smooth, yellow-tan and largely unremarkable. There were notable focal dense fibrous adhesions of the left lung to the lateral chest wall adjacent to an old surgical site.Three microscopic sections were submitted and showed scattered, well-defined, non-caseating granulomas with minimal associated inflammation throughout the parenchyma, some containing prominent asteroid bodies .These granulomas were present within the interstitium and were both peribronchial and perivascular in distribution and consistent with pulmonary sarcoidosis. Bilateral hilar lymphadenopathy was appreciated.Other pathologies considered in the differential diagnosis for the pulmonary granulomas included mycobacterium tuberculosis, histoplasmosis, blastomycosis, bronchocentric granulomatosis, hypersensitivity pneumonitis, pneumoconiosis, foreign body granulomatosis, granulomatosis with polyangiitis, and eosinophilic granulomatosis with polyangiitis, but, no history of recent travel to endemic areas, environmental or occupational exposures, prior illnesses, IV drug use, or evidence of vasculitides make these etiologies less likely. The patient’s lack of systemic symptoms such as fever, night sweats, and weight loss also decreased concern for infection or malignancy. No foreign material was identified under polarized light and specialized stains for mycobacterium and fungal organisms were not deemed necessary. Hypersensitivity pneumonitis (HP) was given additional consideration, but HP granulomas are typically smaller, not discrete, and are associated with greater interstitial chronic inflammation. These characteristics were inconsistent with our findings.Gross examination of the other organs was unremarkable. The liver was enlarged and weighed 2240 grams , but there was no significant edema or cavity effusions. Single histopathologic sections were also taken from the liver, kidney, and brain. The liver section showed mild to moderate sinusoidal dilation and congestion but no necrosis or granulomas. No histopathological abnormalities were noted in the kidney and brain; the spinal cord was not examined. Toxicology of femoral blood was only positive for tetrahydrocannabinol (THC). The cause of death was determined to be sudden cardiac dysrhythmia due to giant cell myocarditis with a secondary post-mortem discovery of probable pulmonary sarcoidosis.This case contains characteristics typical of GCM but raises interesting questions concerning the defining attributes of GCM, its distinction and possible relationship to sarcoidosis, and overall relation to autoimmune disease. Search criteria on PubMed included “giant cell myocarditis” AND sarcoidosis and yielded 40 results. 34 papers were omitted by the authors, resulting in six included papers describing GCM in the setting of sarcoidosis-,-,Giant cell myocarditis is a rare pathologic entity that has been reported to occur in 0.007-067% of populations across the globe.Davies et al.’sTo further grasp GCM’s complex pathology, it must be differentiated from the similar-appearing cardiac sarcoidosis (CS), which depends solely on the histopathology of the myocardium.Additionally, Okura et al.’s,,,,GCM has diverse presenting symptoms seen throughout the literature including dyspnea, fatigue, palpitations, chest pain, hypotension, headache, runny nose, and myalgias among others.-,,Clinically, GCM and CS usually distinguish themselves quite clearly. Although congestive heart failure, ventricular arrhythmias, and heart block have been associated with both CS and GCM,Cooper et al.’s,-,,,,,-Throughout the literature, GCM has been commonly associated with or suggested to be an autoimmune disorder.,,Perhaps the most influential piece of evidence supporting an autoimmune etiology of GCM was an animal study in 1990.The decedent in this case presented with psoriasis and had the post-mortem diagnosis of probable pulmonary sarcoidosis, two diseases commonly considered to be autoimmune, further supporting the relationship between GCM and autoimmunity.Giant cell myocarditis involves a mixed inflammatory infiltrate of the heart with prominent giant cells and myocyte necrosis. The disease manifests itself most often as a ventricular dysrhythmia, congestive heart failure, or sudden cardiac death but presents with a wide variety of other symptoms. The etiology of the disease has not been officially established but many have noted GCM’s autoimmune nature, so this diagnosis must be considered in patients with pre-existing autoimmune diseases, including sarcoidosis, as seen in this case. Additionally, the presence of sarcoidosis in other organs does not preclude a diagnosis of GCM.The decedent’s cause of death was giant cell myocarditis manifesting as sudden cardiac death. His symptoms were atypical, presenting only with nausea and vomiting the day prior to his death. The history of psoriasis and post-mortem diagnosis of probable pulmonary sarcoidosis revealed an association with autoimmune disorders, a characteristic seen in about 20% of reported cases of GCM. This case demonstrates a unique and rapid manifestation of GCM and raises interesting questions concerning the future research, treatment course, and complex etiology of the disease.