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Abstract Nicotinamide adenine dinucleotide (NAD +) plays a pivotal role in numerous cellular functions. Reduced NAD + levels are postulated to be associated with cancer. As interest in understanding NAD + dynamics in cancer patients with therapeutic applications in mind grows, there remains a shortage of comprehensive data. This study delves into NAD + dynamics in patients undergoing surgery for different digestive system cancers. This prospective study enrolled 99 patients with eight different cancers. Fasting blood samples were obtained during the perioperative period. The concentrations of NAD + , nicotinamide mononucleotide (NMN), and nicotinamide riboside were analyzed using tandem mass spectrometry. After erythrocyte volume adjustment, NAD + remained relatively stable after surgery. Meanwhile, NMN decreased the day after surgery and displayed a recovery trend. Interestingly, liver and pancreatic cancer patients exhibited poor postoperative NMN recovery, suggesting a potential cancer type-specific influence on NAD + metabolism. This study illuminated the behavior of NAD + in surgically treated cancer patients. We identified which cancer types have particularly low levels and at what point depletion occurs during the perioperative period. These insights suggest the need for personalized NAD + supplementation strategies, calibrated to individual patient needs and treatment timelines. Clinical trial registration jRCT1020210066.

Abstract Monitoring dynamic changes in near vision is important for early detection of presbyopia. This study assessed the accuracy and reliability of a new smartphone-based application, the Smart Vision Check (SVC), compared with those of a conventional device (AS-28; Kowa, Aichi, Japan), for measuring near functional visual acuity (NFVA). We enrolled 115 healthy volunteers aged ≥ 20 years with bilateral best-corrected visual acuity of ≥ 20/25. The SVC was designed for use on an Apple iPhone SE2 to measure NFVA by tapping on the orientation icon manually. Conventional FVA was measured using the AS-28 with − 2.50 D added to the best distance correction at baseline. There was no significant difference in NFVA-related measurements between the AS-28 and SVC (P > 0.05). The Spearman correlation coefficients of NFVA measurements between the two devices were over 0.60 (P

Perineural invasion (PNI) is a characteristic invasion pattern of distal cholangiocarcinoma (DCC). Conventional histopathologic examination is a challenging approach to analyze the spatial relationship between cancer and neural tissue in full-thickness bile duct specimens. Therefore, we used a tissue clearing method to examine PNI in DCC with three-dimensional (3D) structural analysis. The immunolabeling-enabled 3D imaging of solvent-cleared organs method was performed to examine 20 DCC specimens from five patients and 8 non-neoplastic bile duct specimens from two controls. The bile duct epithelium and neural tissue were labeled with CK19 and S100 antibodies, respectively. Two-dimensional hematoxylin/eosin staining revealed only PNI around thick nerve fibers in the deep layer of the bile duct, whereas PNI was not identified in the superficial layer. 3D analysis revealed that the parts of DCC closer to the mucosa exhibited more nerves than the normal bile duct. The nerve fibers were continuously branched and connected with thick nerve fibers in the deep layer of the bile duct. DCC formed a tubular structure invading from the epithelium and extending around thin nerve fibers in the superficial layer. DCC exhibited continuous infiltration around the thick nerve fibers in the deep layer. This is the first study using a tissue clearing method to examine the PNI of DCC, providing new insights into the underlying mechanisms.

Abstract Preoperatively accurate evaluation of risk for early postoperative recurrence contributes to maximizing the therapeutic success for intrahepatic cholangiocarcinoma (iCCA) patients. This study aimed to investigate the potential of deep learning (DL) algorithms for predicting postoperative early recurrence through the use of preoperative images. We collected the dataset, including preoperative plain computed tomography (CT) images, from 41 patients undergoing curative surgery for iCCA at multiple institutions. We built a CT patch-based predictive model using a residual convolutional neural network and used fivefold cross-validation. The prediction accuracy of the model was analyzed. We defined early recurrence as recurrence within a year after surgical resection. Of the 41 patients, early recurrence was observed in 20 (48.8%). A total of 71,081 patches were extracted from the entire segmented tumor area of each patient. The average accuracy of the ResNet model for predicting early recurrence was 98.2% for the training dataset. In the validation dataset, the average sensitivity, specificity, and accuracy were 97.8%, 94.0%, and 96.5%, respectively. Furthermore, the area under the receiver operating characteristic curve was 0.994. Our CT-based DL model exhibited high predictive performance in projecting postoperative early recurrence, proposing a novel insight into iCCA management.

Abstract Background Determine whether robotic surgery is more effective than transanal and conventional laparoscopic surgery in preserving bowel and urinary function after total mesorectal excision (TME). Methods Of 79 lower rectal cancer patients who underwent function-preserving TME between 2016 and 2020, 64 patients consented to a prospective questionnaire-based functional observation study (52 responded). At 6 months post-resection or ileostomy closure, Wexner, low anterior resection syndrome (LARS), modified fecal incontinence quality of life, and international prostate symptom scores were used to evaluate bowel and urinary function, comparing robotic surgery (RTME) with transanal (taTME) or conventional laparoscopic surgery (LTME). Results RTME was performed in 35 patients (54.7%), taTME in 15 (23.4%), and LTME in 14 (21.9%). While preoperative bowel/urinary functions were similar in all three procedures, and the distance from the anal verge to tumor was almost the same, more hand-sewn anastomoses were performed and the anastomotic height from the anal verge was shorter in taTME than RTME. At 2 years post-resection, 8 patients (12.5%) had a permanent stoma; RTME showed a significantly lower rate of permanent stoma than taTME (2.9% vs. 40%, p

Abstract The incidence of dry eye disease is increasing worldwide because of the aging population and increasing use of information technology. Dry eye disease manifests as tear-layer instability and inflammation caused by osmotic hypersensitization in tear fluids; however, to our knowledge, no agent that treats both pathologies simultaneously is available. Molecular hydrogen (H2) is known to be effective against various diseases; therefore, we aimed to elucidate the effects of H2 on tear dynamics and the treatment of dry eye disease. We revealed that administering a persistent H2-generating supplement increased the human exhaled H2 concentration (p

Massive intraoperative blood loss (IBL) negatively influence outcomes after surgery for pancreatic ductal adenocarcinoma (PDAC). However, few data or predictive models are available for the identification of patients with a high risk for massive IBL. This study aimed to build a model for massive IBL prediction using a decision tree algorithm, which is one machine learning method. One hundred and seventy-five patients undergoing curative surgery for resectable PDAC at our facility between January 2007 and October 2020 were allocated to training (n = 128) and testing (n = 47) sets. Using the preoperatively available data of the patients (34 variables), we built a decision tree classification algorithm. Of the 175 patients, massive IBL occurred in 88 patients (50.3%). Binary logistic regression analysis indicated that alanine aminotransferase and distal pancreatectomy were significant predictors of massive IBL occurrence with an overall correct prediction rate of 70.3%. Decision tree analysis automatically selected 14 predictive variables. The best predictor was the surgical procedure. Though massive IBL was not common, the outcome of patients with distal pancreatectomy was secondarily split by glutamyl transpeptidase. Among patients who underwent PD (n = 83), diabetes mellitus (DM) was selected as the variable in the second split. Of the 21 patients with DM, massive IBL occurred in 85.7%. Decision tree sensitivity was 98.5% in the training data set and 100% in the testing data set. Our findings suggested that a decision tree can provide a new potential approach to predict massive IBL in surgery for resectable PDAC.

Leber congenital amaurosis type nine is an autosomal recessive retinopathy caused by mutations of the NAD+ synthesis enzyme NMNAT1. Despite the ubiquitous expression of NMNAT1, patients do not manifest pathologies other than retinal degeneration. Here we demonstrate that widespread NMNAT1 depletion in adult mice mirrors the human pathology, with selective loss of photoreceptors highlighting the exquisite vulnerability of these cells to NMNAT1 loss. Conditional deletion demonstrates that NMNAT1 is required within the photoreceptor. Mechanistically, loss of NMNAT1 activates the NADase SARM1, the central executioner of axon degeneration, to trigger photoreceptor death and vision loss. Hence, the essential function of NMNAT1 in photoreceptors is to inhibit SARM1, highlighting an unexpected shared mechanism between axonal degeneration and photoreceptor neurodegeneration. These results define a novel SARM1-dependent photoreceptor cell death pathway and identifies SARM1 as a therapeutic candidate for retinopathies.

Presbyopia treatments using various modalities have been developed recently; however, no standard criteria exist for the diagnosis and treatment endpoint. This study assessed the relationship between the near visual acuity (NVA) and the subjective symptoms of phakic presbyopia and determined the numerical NVA threshold to diagnose phakic presbyopia and evaluate the effectiveness of presbyopia treatment. The binocular distance, NVA with habitual correction, and monocular conventional VA were measured. Patients were asked about their awareness of presbyopia and difficulty performing near tasks. This prospective observational study included 70 patients (mean age, 56 years; range, 32–77). Most patients became aware of presbyopia in their late forties, although some had difficulty with vision-related near tasks before becoming aware of presbyopia. Eighty three percent of patients (20/24) experienced difficulty with near vision-related tasks even with excellent NVA at 40 cm with habitual correction of 0.0 logMAR (20/20 in Snellen VA). In conclusion, the current study showed that patients became aware of presbyopia in their late forties, although some had difficulty with near vision-related tasks before becoming aware of presbyopia. Further investigation should include the proposal of appropriate diagnostic criteria for presbyopia and better management for patients with presbyopia.

Author Summary Sirtuins are nicotinamide adenine dinucleotide-dependent protein deacetylases. Among seven sirtuins, SIRT3 is a key regulator of mitochondrial function. However, functions of SIRT3 in the retina are largely unknown. In this study, we investigated the role of retinal SIRT3 in a mouse model of light-induced retinal degeneration, found that SIRT3 has neuroprotective role in the retina. We demonstrate that SIRT3 deficiency causes acute reactive oxygen species accumulation and endoplasmic reticulum stress in the retina after the light exposure, which leads to increased photoreceptor death, retinal thinning, and decreased retinal function. Using a photoreceptor-derived cell line, we revealed that reactive oxygen species were the upstream initiators of endoplasmic reticulum stress, and decreased superoxide dismutase 2 activity led to elevated intracellular reactive oxygen species. These results suggest that SIRT3 might be a therapeutic target for oxidative stress-induced retinal disorders.

Photoreceptor death is the endpoint of many blinding diseases. Identifying unifying pathogenic mechanisms in these diseases may offer global approaches for facilitating photoreceptor survival. We found that rod or cone photoreceptor-specific deletion of nicotinamide phosphoribosyltransferase (Nampt), the rate-limiting enzyme in the major NAD+ biosynthetic pathway beginning with nicotinamide, caused retinal degeneration. In both cases, we could rescue vision with nicotinamide mononucleotide (NMN). Significantly, retinal NAD+ deficiency was an early feature of multiple mouse models of retinal dysfunction, including light-induced degeneration, streptozotocin-induced diabetic retinopathy, and age-associated dysfunction. Mechanistically, NAD+ deficiency caused metabolic dysfunction and consequent photoreceptor death. We further demonstrate that the NAD+-dependent mitochondrial deacylases SIRT3 and SIRT5 play important roles in retinal homeostasis and that NAD+ deficiency causes SIRT3 dysfunction. These findings demonstrate that NAD+ biosynthesis is essential for vision, provide a foundation for future work to further clarify the mechanisms involved, and identify a unifying therapeutic target for diverse blinding diseases.

Presbyopia is increasing globally due to aging and the widespread use of visual display terminals. Presbyopia is a decrease in the eye’s amplitude of accommodation (AA) due to loss of crystalline lens elasticity. AA differs widely among individuals. We aimed to determine the factors that cause presbyopia, other than advanced age, for early medical intervention. We examined 95 eyes of 95 healthy volunteers (33 men, 62 women) aged 22–62 years (mean: 37.22 ± 9.77 years) with a corrected visual acuity of ≥1.0 and without other eye afflictions except ametropia. Subjective refraction, AA, maximum and minimum pupillary diameters during accommodation, axial length of the eye, and crystalline lens thickness were measured. AA was measured using an auto refractometer/keratometer/tonometer/pachymeter. The difference between maximum and minimum pupillary diameters was calculated. On multiple regression analysis, age and difference in pupillary diameter were both significantly and independently associated with AA in participants aged

Recent progress in molecular analysis has revealed the possible involvement of multiple inflammatory signaling pathways in pathogenesis of retinal degeneration. However, how aberrant signaling pathways cause tissue damage and dysfunction is still being elucidated. Here, we focus on 5'-adenosine monophosphate (AMP)-activated protein kinase (AMPK), originally recognized as a key regulator of energy homeostasis. AMPK is also modulated in response to inflammatory signals, although its functions in inflamed tissue are obscure. We investigated the role of activated AMPK in the retinal neural damage and visual function impairment caused by inflammation. For this purpose, we used a mouse model of lipopolysaccharide-induced inflammation in the retina, and examined the effects of an AMPK activator, 5-aminoimidazole-4-carboxamide ribonucleoside (AICAR). During inflammation, activated AMPK in the neural retina was decreased, but AICAR treatment prevented this change. Moreover, the electroretinogram (ERG) a-wave response, representing photoreceptor function, showed visual dysfunction in this model that was prevented by AICAR. Consistently, the model showed shortened photoreceptor outer segments (OSs) with reduced levels of rhodopsin, a visual pigment concentrated in the OSs, in a post-transcriptional manner, and these effects were also prevented by AICAR. In parallel, the level of activated NF-κB increased in the retina during inflammation, and this increase was suppressed by AICAR. Treatment with an NF-κB inhibitor, dehydroxymethylepoxyquinomicin (DHMEQ) preserved the rhodopsin level during inflammation, suppressing NF-κB. These findings indicated that AMPK activation by AICAR and subsequent NF-κB inhibition had a protective effect on visual function, and that AMPK activation played a neuroprotective role during retinal inflammation.

The retina is one of the major energy consuming tissues within the body. In this context, synaptic transmission between light-excited rod and cone photoreceptors and downstream ON-bipolar neurons is a highly demanding energy consuming process. Sirtuin 6 (SIRT6), a NAD-dependent deacylase, plays a key role in regulating glucose metabolism. In this study, we demonstrate that SIRT6 is highly expressed in the retina, controlling levels of histone H3K9 and H3K56 acetylation. Notably, despite apparent normal histology, SIRT6 deficiency caused major retinal transmission defects concomitant to changes in expression of glycolytic genes and glutamate receptors, as well as elevated levels of apoptosis in inner retina cells. Our results identify SIRT6 as a critical modulator of retinal function, likely through its effects on chromatin.

Background: Hearing preservation after large vestibular schwannoma (VS) removal is challenging and the long‑term outcomes of postoperatively preserved hearing have not been elucidated. Objective: We aimed to clarify long‑term outcomes of hearing preservation after the retrosigmoid large VS removal and to recommend a strategy for treating large VS. Materials and Methods: Hearing preservation with total/nearly total (T/NT) tumor removal was accomplished in six of 129 patients who underwent retrosigmoid large VS (≥3 cm) removal. We evaluated the long‑term outcomes of these six patients. Results: Preoperative hearing of these six patients was 15–68 dB by pure tone audiometry (PTA) (Class I: 2, II: 3, and III: 1 by the Gardner‑Robertson (GR) classification). Postoperatively, magnetic resonance imaging (MRI) with gadolinium administration confirmed T/NT removal, the preserved hearing was 36–88 dB (Class II: 4 and III: 2), and no facial palsy occurred. After long‑term follow‑up (8–16 [median: 11.5] years), five patients maintained hearing of 46–75 dB (Class II: 1 and III: 4) while one lost hearing. Three patients showed small tumor recurrence on MRI; two recurrences were controlled by gamma knife (GK) and one showed minimal change only by observation. Conclusions: Hearing preserved after T/NT removal of large VS is maintained for a long time (>10 years), though tumor recurrence on MRI is somewhat common. Detecting small recurrence early, and regular MRI follow‑up contributes to the long‑term maintenance of hearing. Hearing preservation with tumor removal is a challenging yet worthwhile strategy in large VS patients with preoperative hearing. [ABSTRACT FROM AUTHOR]

Gallium nitride (GaN)-based P-channel (Pch) and N-channel (Nch) metal-oxide-semiconductor field-effect transistors (MOSFETs) with normally off operations were realised. Both Pch and Nch MOSFETs were monolithically fabricated in a polarisation-junction platform wafer. The platform wafer was constructed with a GaN/aluminium GaN/GaN double heterostructure, which has both two-dimensional hole gas (2DHG) and 2D electron gas (2DEG). The drain currents of Pch and Nch MOSFETs flow through 2DHG and 2DEG, respectively. The threshold gate voltages of the fabricated Pch and Nch MOSFETs were -2.7 and 6.7 V, respectively. It was shown that the threshold voltage and the on-state resistance of the Pch MOSFET can be controlled by adjusting the 2DEG potential. Furthermore, using Pch and Nch MOSFETs, complementary MOS inverter operation was demonstrated. [ABSTRACT FROM AUTHOR]

Nicotinamide adenine dinucleotide (NAD+) is an enzyme cofactor or cosubstrate in many essential biological pathways. To date, the primary source of neuronal NAD+ has been unclear. NAD+ can be synthesized from several different precursors, among which nicotinamide is the substrate predominantly used in mammals. The rate-limiting step in the NAD+ biosynthetic pathway from nicotinamide is performed by nicotinamide phosphoribosyltransferase (Nampt). Here, we tested the hypothesis that neurons use intracellular Nampt-mediated NAD+ biosynthesis by generating and evaluating mice lacking Nampt in forebrain excitatory neurons (CaMKIIαNampt-/- mice). CaMKIIαNampt-/- mice showed hippocampal and cortical atrophy, astrogliosis, microgliosis, and abnormal CA1 dendritic morphology by 2-3 months of age. Importantly, these histological changes occurred with altered intrahippocampal connectivity and abnormal behavior; including hyperactivity, some defects in motor skills, memory impairment, and reduced anxiety, but in the absence of impaired sensory processes or long-term potentiation of the Schaffer collateral pathway. These results clearly demonstrate that forebrain excitatory neurons mainly use intracellular Nampt-mediated NAD+ biosynthesis to mediate their survival and function. Studying this particular NAD+ biosynthetic pathway in these neurons provides critical insight into their vulnerability to pathophysiological stimuli and the development of therapeutic and preventive interventions for their preservation. [ABSTRACT FROM AUTHOR]

The article discusses the results of a study which examines the role of fission yeast leucine-rich repeat protein Lrp1 in the morphogenesis of cell. The authors explained that cell morphogenesis is coordinately regulated in eukaryotes with cell cycle. They showed that Lrp1 is vital for cell growth and cell morphogenesis as a recognized component of morphogenesis Orb6 network. The localization of Lrp1 to the spindle pole bodies and its interaction with protein Nak1 are explained.

AbstractThe process of aging involves the accumulating changes in the microenvironment that lead to cell senescence or apoptosis, and subsequent tissue or organ dysfunction. Multiple extrinsic and intrinsic events that cause DNA instability are associated with aging. Cells containing unstable DNA are biologically vulnerable, and if the DNA damage is too great for the cell to repair, it becomes senescent or dies by apoptosis. Thus, the cell’s capacity to repair its DNA determines the progress of aging, at least in part. Here, we focus on the sirtuins, the mammalian homologs of the yeast life-span-extending molecule, Sir2. Among the sirtuin family proteins in mammals, the one most similar to yeast Sir2 is SIRT1, which is involved in multiple pathways, including the repair of DNA double-strand breaks. Although the role of SIRT1 in mammalian longevity is not clear, it is expressed throughout the retina, where it may suppress aging. In fact, a mutant mouse model of retinal degeneration shows an abnormal subcellular localization of SIRT1 protein and accelerated retinal cell apoptosis. Further analyses are required to elucidate the mechanism of DNA damage and repair, including the contributions of the sirtuins, in the aged or diseased retinas, which will help us understand the mechanisms of retinal aging.Copyright © 2010 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]