FUS regulates RAN translation through modulating the G-quadruplex structure of GGGGCC repeat RNA in C9orf72-linked ALS/FTD.

Abnormal expansions of GGGGCC repeat sequence in the noncoding region of the C9orf72 gene is the most common cause of familial amyotrophic lateral sclerosis and frontotemporal dementia (C9-ALS/FTD). The expanded repeat sequence is translated into dipeptide repeat proteins (DPRs) by noncanonical repeat-associated non-AUG (RAN) translation. Since DPRs play central roles in the pathogenesis of C9-ALS/FTD, we here investigate the regulatory mechanisms of RAN translation, focusing on the effects of RNA-binding proteins (RBPs) targeting GGGGCC repeat RNAs. Using C9-ALS/FTD model flies, we demonstrated that the ALS/FTD-linked RBP FUS suppresses RAN translation and neurodegeneration in an RNA-binding activity-dependent manner. Moreover, we found that FUS directly binds to and modulates the G-quadruplex structure of GGGGCC repeat RNA as an RNA chaperone, resulting in the suppression of RAN translation in vitro. These results reveal a previously unrecognized regulatory mechanism of RAN translation by G-quadruplex-targeting RBPs, providing therapeutic insights for C9-ALS/FTD and other repeat expansion diseases.

Simultaneous presence of the hepato-spleno-mesenteric trunk, a common trunk for both inferior phrenic arteries, the left gastric artery, and a common hepatic artery that ran behind the portal vein in a patient with gastric cancer.

The celiac artery usually trifurcates into the common hepatic artery, splenic artery, and left gastric artery, but it is known to present several anatomical variations. In such cases, detailed knowledge of the variation is needed preoperatively to safely perform surgery. A 77-year-old woman was referred to our hospital for the treatment of gastric cancer. She had a triple anatomical variation: simultaneous presence of the hepato-spleno-mesenteric trunk, a common trunk for both inferior phrenic arteries and the left gastric artery, and a common hepatic artery that ran behind the portal vein. We detected this variation on routine preoperative multidetector computed tomography angiography, and safely and adequately performed laparoscopic distal gastrectomy.

Description of the Vascular Anatomy of Livers with Absence of the Portal Bifurcation.

BACKGROUND: The absence of the portal bifurcation (APB) is a rare anatomic variation, in which the horizontal part of the left portal vein (PV) is missing. The aim of this study was to identify the vascular architecture in livers with APB. METHODS: Computed tomography data for 17,651 patients were reviewed; five patients (0.03%) were found to present with APB. The liver volume and anatomy of APB patients were compared with those of 30 patients with normal livers. RESULTS: All the APB patients exhibited an independent posterior branch of the PV. The intrahepatic left PV (LPV) ran through either the ventral (n = 2, 40%) or dorsal side (n = 3, 60%) of the middle hepatic vein. The frequency of medial branches diverging from the LPV was higher in patients with APB than in normal patients (p < 0.001). The left hepatic duct (LHD) ran through the inside of the left lobe along the left PV in 40% of the patients with APB, whereas in the remaining 60% of the patients with APB, the LHD ran on the outside of the liver separately from the left PV and joined the right hepatic duct. The liver volume of the left lateral section was significantly smaller (p = 0.014), and the posterior section was significantly larger (p = 0.014) in patients with APB than in patients with normal livers. CONCLUSION: The unique anatomical characteristics and the positional relation of the vessels should be considered preoperatively in patients with APB.

An aberrant venous channel mimicking the perilabyrinthine cells in the petrous bone of a patient with vestibular schwannoma: illustrative case.

BACKGROUND: Anatomical variations, such as high jugular bulbs and air cell development in the petrosal bone, should be evaluated before surgery. Most bone defects in the internal auditory canal (IAC) posterior wall are observed in the perilabyrinthine cells. An aberrant vascular structure passing through the petrous bone is rare. OBSERVATIONS: A 48-year-old man presented with a right ear hearing disturbance. Magnetic resonance imaging revealed a 23-mm contrast-enhancing mass in the right cerebellopontine angle extending into the IAC, consistent with a right vestibular schwannoma. Preoperative bone window computed tomographic scans showed bone defects in the IAC posterior wall, which ran farther posteroinferiorly in the petrous bone, reaching the medial part of the jugular bulb. The tumor was accessed via a lateral suboccipital approach. There was no other major vein in the cerebellomedullary cistern, except for the vein running from the brain stem to the IAC posterior wall. To avoid complications due to venous congestion, the authors did not drill out the IAC posterior wall or remove the tumor in the IAC. LESSONS: Several aberrant veins in the petrous bone are primitive head sinus remnants. Although rare, their surgical implication is critical in patients with vestibular schwannomas.

Topographical relationship between the accessory hepatic duct and the hepatic artery system.

Hepatic biliary injury is one of the most common complications in cholecystectomy and is frequently accompanied by arterial injuries. Because there are several anatomical variations of the hepatic ducts, including the accessory hepatic ducts (AHDs), it is important to consider not only the anatomical position of the hepatic ducts but also those of the AHDs in cholecystectomy. However, the topographical relationships between the AHDs and the hepatic arteries are still poorly understood. In the present study we show that AHDs were observed in 7 out of 59 (11.9%) of the cadavers. There was a single AHD in the 6 out of the 7 cadavers and double AHDs in one. In these cases, the right AHDs emerged from the anterior medial segment of the liver piercing the parenchyma, while the left AHDs emerged directly from the anterior part of the caudate lobe. The right AHDs ran anterior to the right hepatic artery, while the left AHDs ran posterior to the hepatic arteries. The topographical relationship between the AHD and the hepatic artery system was thus reversed in the cases of the right and the left AHDs.

Partial sleep deprivation after an acute exercise session does not augment hepcidin levels the following day.

The purpose of the present study was to determine the effects of partial sleep deprivation (PSD) after an exercise session in the evening on the endurance exercise-induced hepcidin response the following morning. Ten recreationally trained males participated under two different conditions. Each condition consisted of 2 consecutive days of training (days 1 and 2). On day 1, participants ran for 60 min at 75% of maximal oxygen uptake ( V˙ O2max ) followed by 100 drop jumps. Sleep duration at night was manipulated, with a normal length of sleep (CON condition, 23:00-07:00 hr) or a shortened length of sleep (PSD condition). On the morning of day 2, the participants ran for 60 min at 65% of V˙ O2max . Sleep duration was significantly shorter under the PSD condition (141.2 ± 13.3 min) than under the CON condition (469.0 ± 2.3 min, p < .0001). Serum hepcidin, plasma interleukin (IL)-6, serum haptoglobin, iron, and myoglobin levels did not differ significantly between the conditions (p > .05) on the morning (before exercise) of day 2. Additionally, the 3-hr postexercise levels for the hematological variables were not significantly different between the two conditions (p > .05). In conclusion, the present study demonstrated that a single night of PSD after an exercise session in the evening did not affect baseline serum hepcidin level the following morning. Moreover, a 60 min run the following morning increased serum hepcidin and plasma IL-6 levels significantly, but the exercise-induced elevations were not affected by PSD.

The DNA damage response (DDR) is induced by the C9orf72 repeat expansion in amyotrophic lateral sclerosis.

Amyotrophic lateral sclerosis (ALS) is a rapidly progressing neurodegenerative disease affecting motor neurons. Hexanucleotide (GGGGCC) repeat expansions in a non-coding region of C9orf72 are the major cause of familial ALS and frontotemporal dementia (FTD) worldwide. The C9orf72 repeat expansion undergoes repeat-associated non-ATG (RAN) translation to produce five dipeptide repeat proteins (DRPs), including poly(GR) and poly(PR). Whilst it remains unclear how mutations in C9orf72 lead to neurodegeneration in ALS/FTD, dysfunction to the nucleolus and R loop formation are implicated as pathogenic mechanisms. These events can damage DNA and hence genome integrity. Cells activate the DNA damage response (DDR) with the aim of repairing this damage. However, if the damage cannot be repaired, apoptosis is triggered. In lumbar motor neurons from C9orf72-positive ALS patients, we demonstrate significant up-regulation of markers of the DDR compared to controls: phosphorylated histone 2AX (γ-H2AX), phosphorylated ataxia telangiectasia mutated (p-ATM), cleaved poly (ADP-Ribose) polymerase 1 (PARP-1) and tumour suppressor p53-binding protein (53BP1). Similarly, significant up-regulation of γ-H2AX and p-ATM was detected in neuronal cells expressing poly(GR)100 and poly(PR)100 compared to controls, revealing that DNA damage is triggered by the DRPs. Nucleophosmin (NPM1) is a histone chaperone induced during the DDR, which interacts with APE1 to enhance DNA repair. We also demonstrate that more NPM1 precipitates with APE1 in C9orf72 patients compared to controls. Furthermore, overexpression of NPM1 inhibits apoptosis in cells expressing poly(GR)100 and poly(PR)100. This study therefore demonstrates that DNA damage is activated by the C9orf72 repeat expansion in ALS.

Anatomy of the superficial layer of superficial fascia around the nipple-areola complex.

BACKGROUND: The periareolar incision is the preferred method for mammaplasty because of the minimal scarring, and suturing of the superficial fascial system (SFS) is useful for avoiding hypertrophic scarring. In this report, we describe the anatomical location of the SFS around the nipple-areolar complex (NAC) and its histological structure. METHODS: To define the location of the SFS, 20 healthy women were assessed by ultrasonography, and sections of the NAC of 10 female cadavers were examined under a light microscope. RESULTS: Ultrasonographic examination of sagittal sections of the breast revealed a hyperdense line immediately beneath the skin, which ran parallel with the skin and turned under the NAC. At the turning point, the line thickened to an average of 3.09 mm. The distance between the nipple and the thickest point of the hyperdense line was 10.14 mm on average. Histological structures of the line were collagen and elastic fibers containing smooth muscles that were connected to the dermis and adipose tissue. At the turning point, nerves, blood vessels, and mammary ducts were irregularly observed in the area of collagen and elastic fibers. These structures were intermingled, and the fiber bundle was very thick. CONCLUSIONS: The thickest area of the turning point is an area of the superficial layer of superficial fascia, which is a key structure around the NAC. The detailed anatomical data shown in our study provide good morphological landmarks for the closure of periareolar incisions. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors http://www.springer.com/00266.

Conjoint pathologic cascades mediated by ALS/FTLD-U linked RNA-binding proteins TDP-43 and FUS.

The RNA-binding proteins TAR DNA-binding protein (TDP-43) and fused in sarcoma (FUS) play central roles in neurodegeneration associated with familial amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration with ubiquitin-positive inclusions (FTLD-U). Normally localized in the nucleus, in sites affected by ALS and FTLD-U they are mislocalized to the cytoplasm and form cytoplasmic inclusions. TDP-43 and FUS are transported to the nucleus in a Ran-GTPase-dependent manner via nuclear import receptors, but they also contribute to the formation of stress granules (SGs), which are intracytoplasmic structures incorporating RNA. C-terminal truncations of TDP-43 eliminate the nuclear transport signal and cause mislocalization of the protein to the cytoplasm, where it accumulates and forms SGs. ALS-associated FUS mutations impair nuclear transport and cause mislocalization of FUS to the cytoplasm, where it also contributes to assembly of SGs. Furthermore, the ALS susceptibility factor ataxin-2, recently identified as a potent modifier of TDP-43 toxicity, is also a predicted cytoplasmic RNA-binding protein and a constituent protein of SGs, suggesting that it is a part of the common pathologic cascade formed by TDP-43 and FUS. Thus, we propose that excessive mislocalization of the RNA-binding proteins TDP-43, FUS, and ataxin-2 into the cytoplasm leads to impairment of the RNA quality control system, forming the core of the ALS/FTLD-U degenerative cascade. In this review, we discuss the molecular basis of the novel disease spectrum of ALS/FTLD-U, including the neurodegenerative mechanism of the cytoplasmic RNA-binding proteins TDP-43 and FUS and the possibility of a novel therapeutic strategy.

Nuclear transport impairment of amyotrophic lateral sclerosis-linked mutations in FUS/TLS.

OBJECTIVE: The fused in sarcoma/translated in liposarcoma (FUS/TLS) protein was recently identified as a cause of familial amyotrophic lateral sclerosis (ALS), as well as a major component of the inclusion bodies found in subtypes of frontotemporal lobar degeneration (FTLD). These diseases now are collectively known as the novel clinical spectrum, FUS proteinopathy. ALS-linked mutations of FUS are clustered in the C-terminal region; however, the molecular properties of mutant FUS remain unclear. To gain insight into the pathogenesis of FUS proteinopathy, we examined the biochemical and cellular characteristics of mutant FUS in expressing cells. METHODS AND RESULTS: Expression of ALS-linked FUS mutations resulted in their assembly into cytoplasmic stress granules (SGs), cellular structures that package mRNA and RNA-binding proteins during cell stress. A deletion mutant series revealed that the C-terminal region in FUS is critical for nuclear retention via Ran guanosine triphosphatase-dependent transport machinery. A parallel study of subcellular distribution revealed that ALS-linked mutants additively disturb the function of the C-terminus for nuclear traffic, resulting in cytoplasmic accumulation and the formation of SGs. INTERPRETATION: This study demonstrates that mutant FUS, which is missing the nuclear traffic activity of the C-terminus, is dislocated to cytoplasm and assembled into SGs, indicating that disruption of translational regulation and metabolism of mRNA via inappropriate/excessive SGs may be crucial for FUS proteinopathies. Our findings provide new biological and pathological insights into the FUS protein that should help our understanding of the pathogenesis of ALS/FTLD.

Mechanical stress-induced reactive gliosis in the auditory nerve and cochlear nucleus.

OBJECT: Hearing levels following microsurgical treatment gradually deteriorate in a number of patients treated for vestibular schwannoma (VS), especially in the subacute postoperative stage. The cause of this late-onset deterioration of hearing is not completely understood. The aim of this study was to investigate the possibility that reactive gliosis is a contributory factor. METHODS: Mechanical damage to nerve tissue is a feature of complex surgical procedures. To explore this aspect of VS treatment, the authors compressed rat auditory nerves with 2 different degrees of injury while monitoring the compound action potentials of the auditory nerve and the auditory brainstem responses. In this experimental model, the axons of the auditory nerve were quantitatively and highly selectively damaged in the cerebellopontine angle without permanent compromise of the blood supply to the cochlea. The temporal bones were processed for immunohistochemical analysis at 1 week and at 8 weeks after compression. RESULTS: Reactive gliosis was induced not only in the auditory nerve but also in the cochlear nucleus following mechanical trauma in which the general shape of the auditory brainstem response was maintained. There was a substantial outgrowth of astrocytic processes from the transitional zone into the peripheral portion of the auditory nerve, leading to an invasion of dense gliotic tissue in the auditory nerve. The elongated astrocytic processes ran in parallel with the residual auditory neurons and entered much further into the cochlea. Confocal images disclosed fragments of neurons scattered in the gliotic tissue. In the cochlear nucleus, hypertrophic astrocytic processes were abundant around the soma of the neurons. The transverse diameter of the auditory nerve at and proximal to the compression site was considerably reduced, indicating atrophy, especially in rats in which the auditory nerve was profoundly compressed. CONCLUSIONS: The authors found for the first time that mechanical stress to the auditory nerve causes substantial reactive gliosis in both the peripheral and central auditory pathways within 1-8 weeks. Progressive reactive gliosis following surgical stress may cause dysfunction in the auditory pathways and may be a primary cause of progressive hearing loss following microsurgical treatment for VS.

The anterior branch of the left inferior phrenic artery arising from the right inferior phrenic artery: an angiographic and CT study.

The purpose of this study was to retrospectively analyze the frequency and anatomical pattern of the anterior branch of the left inferior phrenic artery (LIPA) arising from the right inferior phrenic artery (RIPA). Angiography of the RIPA for patients (n = 140) with hepatic malignancy was retrospectively reviewed. The frequency at which the anterior branch of the LIPA arose from the RIPA was 14.3% (20 of 140 patients [pts]). Among the three branches that may arise from the RIPA in these cases (the anterior branch of the LIPA and the anterior and posterior branches of the RIPA), the anterior branch of the LIPA was the first branch of the RIPA in 9 of 20 pts (45%), and the posterior branch of the RIPA in 11 of 20 pts (55%). The anterior branch of the LIPA ran along the ventral side of the esophagus or stomach and supplied the esophagogastric region and dome of the left diaphragm in all cases. In conclusion, the anterior branch of the LIPA arises from the RIPA at a comparatively high frequency. In embolization of the RIPA, to effectively treat and avoid possible complications, interventionalists should be aware of this potential variant anatomy.

Clinical anatomy in the neck region--the position of external and internal carotid arteries may be reversed.

Knowledge of clinical anatomy in the neck region is useful for the diagnosis of primary tumors and metastatic lymph nodes. Arteries and nerves in the neck region of forty Japanese cadavers (80 cases), 18 males (36 cases) and 22 females (44 sides) were studied by dissection. We obtained the following results. Reverse of the location of the external and internal carotid arteries was found in 5 cases (6.3%). The course of the hypoglossal nerve made an acute curve and ran anterior-inferior in the neck region. In regard to the height of bifurcation of the common carotid artery (CC), high bifurcation was seen in 25 (31.2%), standard bifurcation in 46 (57.5%), and low bifurcation in 9 (11.3%) in a total of 80 cases. Furthermore, the facial artery had the largest inner diameter among the branches of the external carotid artery. Based on these findings, the facial artery will be one of the most beneficial arteries for transplantation as a recipient artery.

Supernumerary extensor pollicis longus tendon: a case report.

We report a rare case in which the extensor pollicis longus (EPL) tendon was separated into 2 slips at the site of origin, ran an abnormal course across the wrist, and combined in the vicinity of the metacarpophalangeal (MCP) joint; the tendon on the radial side passed through another tendon sheath between the first and second compartments and the tendon on the ulnar side passed over the extensor retinaculum.

Ultrastructural study of acquired pili torti-like hair defects accompanying pseudopelade.

Acquired structural hair defects are caused by various physical and chemical manipulations. Plucked hairs and hair follicle biopsy specimens of pili torti-like hairs that arose from pseudopelade scalp were studied. In scanning electron microscopy, the hair shafts had a segmental pili torti-like appearance, accompanied by oblique or longitudinal grooves and ridges. In light microscopy, the hair follicles showed an asymmetric hair bulb and inner root sheath, and a shortened keratogenous zone within sclerosing fibrous connective tissue. In transmission electron microscopy, the numbers and thickness of the hair cuticle cells were different on the opposite sides of the hair shaft. The hair cuticle was irregularly shaped and formed asymmetric waves. The tonofilaments in the hair cortex ran almost parallel to the hair axis. From these findings, it was clear that the grooves and ridges were produced by the deformed hair cuticle and cortex, whose shapes were modulated by the asymmetric inner root sheath. This asymmetry most likely resulted from a dysfunctional dermal papilla, which was affected by fibrosis. The pili torti-like appearance appeared to be caused by the grooves and ridges that ran obliquely on the hair shaft surface.

Morphological investigation of the enteric nervous system in Hirschsprung's disease and hypoganglionosis using whole-mount colon preparation.

BACKGROUND/PURPOSE: A suction rectal mucosal biopsy with positive staining for acetylcholinesterase is a useful test for diagnosis of Hirschsprung's disease (HD). However, hypoganglionosis has not been diagnosed by a rectal mucosal biopsy. The authors morphologically examined the enteric nervous systems in HD and hypoganglionosis patients using whole-mount preparations. METHODS: Six HD patients, two hypoganglionosis patients, and 10 with normally innervated colons were examined. Colonic specimens were incubated with the primary antibodies against protein gene product 9.5 (PGP 9.5) mixed with S-100b protein, tyrosine hydroxylase (TH), calcitonin gene-related peptide (CGRP), substance P (SP), and neurofilament protein 200 kDa (NFH). They were observed by histochemical technique using light-microscopy in whole-mount preparations. RESULTS: The aganglionic distal colon had thick nerve strands stained with PGP 9.5 mixed with S100 or NFH located in the layer between the longitudinal muscle and the circular one, and the submucosal layer. The nerve strands in the myenteric layer contained few CGRP- and SP-positive fibers and ran along the long axis of the intestine. Ganglion cells appeared along with those thick nerve strands in the transitional zone of HD. In hypoganglionosis, we found small myenteric ganglia with no thick nerve strands. CONCLUSIONS: The enteric nervous system in oligoganglionic segments of HD morphologically differed from the one in hypoganglionosis. A suction rectal mucosal biopsy would be of no use in the diagnosis of hypoganglionosis.

Hereditary nephritis in children with and without characteristic glomerular basement membrane alterations.

Characteristic ultrastructural alterations of the glomerular basement membrane (GBM) have been reported in hereditary nephritis. However, these GBM changes are not present in all patients with hereditary nephritis. In a retrospective study of 42 children with hereditary nephritis characteristic GBM changes were found in 28. The clinical features, renal biopsy findings and subsequent course were compared with those in the 14 without such changes. All 42 patients had hematuria. Eighty-two percent of the patients with the GBM changes showed progression of nephritis and 39% showed neurosensory deafness when last seen. In contrast, all patients without the GBM changes had a normal audiogram, ran a nonprogressive course and had hematuria only when last seen. Light microscopy of renal biopsy specimens revealed segmental glomerular sclerosis and interstitial foam cells only in patients with the GBM changes. Our study shows that the presence or absence of these GBM changes is the most reliable indicator of the prognosis in children with hereditary nephritis.