Loss Of Fibers Research Articles

Impact of NSD1 Alternative Transcripts in Actin Filament Formation and Cellular Division Pathways in Fibroblasts.

Germline variants in the NSD1 gene are responsible for Sotos syndrome, while somatic variants promote neoplastic cell transformation. Our previous studies revealed three alternative RNA isoforms of NSD1 present in fibroblast cell lines (FBs): the canonical full transcript and 2 alternative transcripts, termed AT2 (NSD1 Δ5Δ7) and AT3 (NSD1 Δ19-23 at the 5' end). The precise molecular pathways affected by each specific isoform of NSD1 are uncharacterized to date. To elucidate the role of these isoforms, their expression was suppressed by siRNA knockdown in FBs and protein expression and transcriptome data was explored. We demonstrate that one gene target of NSD1 isoform AT2 is ARP3 actin-related protein 3 homolog B (ACTR3B). We show that loss of both canonical NSD1 and AT2 isoforms impaired the ability of fibroblasts to regulate the actin cytoskeleton, and we observed that this caused selective loss of stress fibers. Our findings provide novel insights into NSD1 function by distinguishing isoform function and demonstrating an essential role of NSD1 in regulating the actin cytoskeleton and stress fiber formation in fibroblasts.

Effect of 28 days treatment of baricitinib on mechanical allodynia, osteopenia, and loss of nerve fibers in an experimental model of type-1 diabetes mellitus.

Type-1 diabetes mellitus (T1DM) is associated with numerous health problems, including peripheral neuropathy, osteoporosis, and bone denervation, all of which diminish quality of life. However, there are relatively few therapies to treat these T1DM-related complications. Recent studies have shown that Janus kinase (JAK) inhibitors reverse aging- and rheumatoid arthritis-induced bone loss and reduce pain associated with peripheral nerve injuries, and rheumatoid arthritis. Thus, we assessed whether a JAK1/JAK2 inhibitor, baricitinib, ameliorates mechanical pain sensitivity (a measure of peripheral neuropathy), osteoporosis, and bone denervation in the femur of mice with T1DM. Female ICR mice (13 weeks old) received five daily administrations of streptozotocin (ip, 50mg/kg) to induce T1DM. At thirty-one weeks of age, mice were treated with baricitinib (po; 40mg/kg/bid; for 28 days) or vehicle. Mechanical sensitivity was evaluated at 30, 33, and 35 weeks of age on the plantar surface of the right hind paw. At the end of the treatment, mice were sacrificed, and lower extremities were harvested for microcomputed tomography and immunohistochemistry analyses. Mice with T1DM exhibited greater blood glucose levels, hind paw mechanical hypersensitivity, trabecular bone loss, and decreased density of calcitonin gene-related peptide-positive and tyrosine hydroxylase-positive axons within the marrow of the femoral neck compared to control mice. Baricitinib treatment significantly reduced mechanical hypersensitivity and ameliorated sensory and sympathetic denervation at the femoral neck, but it did not reverse trabecular bone loss. Our findings suggest that baricitinib may represent a new therapeutic alternative to treat T1DM-induced peripheral neuropathy and bone denervation.

Neuroinflammation evoked mechanisms for neuropathic itch in the spared nerve injury mouse model of neuropathic pain

A large portion of neuropathic pain suffering patients may also concurrently experience neuropathic itch, with a negative impact on the quality of life. The limited understanding of neuropathic itch and the low efficacy of current anti-itch therapies dictate the urgent need of a better comprehension of molecular mechanisms involved and development of relevant animal models. This study was aimed to characterize the itching phenotype in a model of trauma-induced peripheral neuropathy, the spared nerve injury (SNI), and the molecular events underlying the overlap with the nociceptive behavior. SNI mice developed hyperknesis and spontaneous itch 7–14 days after surgery that was prevented by gabapentin treatment. Itch was associated with pain hypersensitivity, loss of intraepidermal nerve fiber (IENF) density and increased epidermal thickness. In coincidence with the peak of scratching behavior, SNI mice showed a spinal overexpression of IBA1 and GFAP, microglia and astrocyte markers respectively. An increase of the itch neuropeptide B-type natriuretic peptide (BNP) in NeuN+ cells, of its downstream effector interleukin 17 (IL17) along with increased pERK1/2 levels occurred in the spinal cord dorsal horn and DRG. A raise in BNP and IL17 was also detected at skin level. Stimulation of HaCat cells with conditioned medium from BV2-stimulated SH-SY5Y cells produced a dramatic reduction of HaCat cell viability. This study showed that SNI mice might represent a model for neuropathic itch and pain. Collectively, our finding suggest that neuropathic itch might initiate at spinal level, then affecting skin epidermis events, through a glia-mediated neuroinflammation-evoked BNP/IL17 mechanism.

Hidden hearing loss in a Charcot-Marie-Tooth type 1A mouse model.

Hidden hearing loss (HHL), a recently described auditory neuropathy characterized by normal audiometric thresholds but reduced sound-evoked cochlear compound action potentials, has been proposed to contribute to hearing difficulty in noisy environments in people with normal hearing thresholds, a widespread complaint. While most studies on HHL pathogenesis have focused on inner hair cell (IHC) synaptopathy, we recently showed that transient auditory nerve (AN) demyelination also causes HHL in mice. To test the impact of myelinopathy on hearing in a clinically relevant model, we studied a mouse model of Charcot-Marie-Tooth type 1A (CMT1A), the most prevalent hereditary peripheral neuropathy in humans. CMT1A mice exhibited the functional hallmarks of HHL together with disorganization of AN heminodes near the IHCs with minor loss of AN fibers. These results support the hypothesis that mild disruptions of AN myelination can cause HHL, and that heminodal defects contribute to the alterations in the sound-evoked cochlear compound action potentials seen in this mouse model. Also, these findings suggest that patients with CMT1A or other mild peripheral neuropathies are likely to suffer from HHL. Furthermore, these results suggest that studies of hearing in CMT1A patients might help develop robust clinical tests for HHL, which are currently lacking.

Protein-extending ACTN2 frameshift variants cause variable myopathy phenotypes by protein aggregation.

The objective of the study is to characterize the pathomechanisms underlying actininopathies. Distal myopathies are a group of rare, inherited muscular disorders characterized by progressive loss of muscle fibers that begin in the distal parts of arms and legs. Recently, variants in a new disease gene, ACTN2, have been shown to cause distal myopathy. ACTN2, a gene previously only associated with cardiomyopathies, encodes alpha-actinin-2, a protein expressed in both cardiac and skeletal sarcomeres. The primary function of alpha-actinin-2 is to link actin and titin to the sarcomere Z-disk. New ACTN2 variants are continuously discovered; however, the clinical significance of many variants remains unknown. Thus, lack of clear genotype-phenotype correlations in ACTN2-related diseases, actininopathies, persists. Functional characterization in C2C12 cell model of several ACTN2 variants is conducted, including frameshift and missense variants associated with dominant and recessive actininopathies. We assess the genotype-phenotype correlations of actininopathies using clinical data from several patients carrying these variants. The results show that the missense variants associated with a recessive form of actininopathy do not cause detectable alpha-actinin-2 aggregates in the cell model. Conversely, dominant frameshift variants causing a protein extension do form alpha-actinin-2 aggregates. The results suggest that alpha-actinin-2 aggregation is the disease mechanism underlying some dominant actininopathies, and thus, we recommend that protein-extending frameshift variants in ACTN2 should be classified as pathogenic. However, this mechanism is likely elicited by only a limited number of variants. Alternative functional characterization methods should be explored to further investigate other molecular mechanisms underlying actininopathies.

Electroacupuncture reduces corpus callosum injury in rats with permanent cerebral ischemia by inhibiting the activation of high-mobility group box 1 protein and the receptor for advanced glycation end products.

Previous studies have shown that cerebral ischemia can cause white matter injury in the brain. This study aimed to investigate the potential mechanism of electroacupuncture (EA) at the Baihui (GV20) and Zusanli (ST36) acupoints in protecting white matter. Sprague-Dawley rats were used to establish permanent middle cerebral artery occlusion (pMCAO) rat models. Comprehensive motor functions were assessed using the mesh experiment. Morphological changes in the myelin sheath were assessed with Luxol fast blue staining. Morphological changes in oligodendrocytes and myelinated axons were evaluated using Nissl staining. The expressions of high-mobility group box 1 protein (HMGB1) and the receptor for advanced glycation end products (RAGE) in the corpus callosum were detected by immunohistochemical staining and Western blot analysis. pMCAO caused severe injury to the corpus callosum, evidenced by significant loss of white matter fibers and myelinated axons, and induced overexpression of HMGB1 and RAGE in the corpus callosum. EA treatment significantly improved comprehensive motor function alleviated white matter damage, and downregulated the expression of HMGB1 and RAGE. Its effects were comparable to those of FPS-ZM1, a RAGE receptor inhibitor. In conclusion, EA effectively improves comprehensive motor function in rats with cerebral infarction and alleviates corpus callosum injury. This effect may be related to the inhibition of HMGB1 and RAGE overexpression.

Retrospective Single-Center Case Study of Clinical Variables and the Degree of Actinic Elastosis Associated with Rare Skin Cancers.

(1) Background: Rare skin cancers include epithelial, neuroendocrine, and hematopoietic neoplasias as well as cutaneous sarcomas. Ultraviolet (UV) radiation and sunburns are important drivers for the incidence of certain cutaneous sarcomas; however, the pathogenetic role of UV light is less clear in rare skin cancers compared to keratinocyte cancer and melanoma. In this study, we compared the degree of actinic elastosis (AE) as a surrogate for lifetime UV exposure among selected rare skin cancers (atypical fibroxanthoma [AFX], pleomorphic dermal sarcoma [PDS], dermatofibrosarcoma protuberans [DFSP], Kaposi sarcoma [KS], Merkel cell carcinoma [MCC], and leiomyosarcoma [LMS]) while taking into account relevant clinical variables (age, sex, and body site). (2) Methods: We newly established a semi-quantitative score for the degree of AE ranging from 0 = none to 3 = total loss of elastic fibers (basophilic degeneration) and multiplied it by the perilesional vertical extent (depth), measured histometrically (tumor-associated elastosis grade (TEG)). We matched the TEG of n = 210 rare skin cancers from 210 patients with their clinical variables. (3) Results: TEG values were correlated with age and whether tumors arose on UV-exposed body sites. TEG values were significantly higher in AFX and PDS cases compared to all other analyzed rare skin cancer types. As expected, TEG values were low in DFSP and KS, while MCC cases exhibited intermediate TEG values. (4) Conclusions: High cumulative UV exposure is more strongly associated with AFX/PDS and MCC than with other rare skin cancers. These important results expand the available data associated with rare skin cancers while also offering insight into the value of differentiating among these tumor types based on their relationship with sun exposure, potentially informing preventative, diagnostic and/or therapeutic approaches.

Brillouin-based fiber loss measurement for PON using ERA-BOTDA with differential width pairs of frequency-swept pump pulses.

We demonstrate Brillouin-based loss distribution measurement for passive optical networks with differential width pairs of frequency-swept pump pulses that can suppress the spatial resolution degradation, especially those created by large loss events typical of an 8-branch splitter. Based on the acoustic wave simulation of a frequency-swept pump pulse, we investigate the arrangement of the modulation frequency within the optical pulse. A preliminary experiment is conducted on a 5-dB loss event near an 8-branch splitter. The results show that the proposed technique can accurately measure loss events with a spatial resolution of better than 3 m.

Fibre persistence on submerged substrates: The effect of flow rate over extended submersion periods

Through both casework and research, fibres have been found to have the particularly useful ability to persist and remain exploitable after submersion. However, direct analysis of the persistence ability remains in early stages, and in particular, submersion times above a day have not been thoroughly studied. This study aims to both extend understanding of the impact of flow rate and submersion periods of up to 28 days. A blended polyester/cotton green fabric was abraded to increase transfer and then dragged over a black cotton substrate. Six replicates of these substrates were then submerged in artificial flow cells at various flow rates for 28 days. These were illuminated under UV light and photographed prior to submersion, at set times during submersion and after submersion. Another set of six replicates were imaged, submerged into a river and then recovered and re-imaged after 28 days. The population of fibres was then counted using these photographs, and a mix of one-way and two-way ANOVA tests were applied, in combination with Tukey’s HSD, to detect significant differences across time and flow rate categories. Loss predominantly occurred on within the first 24 hours, in agreement with previous work. However, distinct from previous work there was a slow, approximately logarithmic loss over the balance of the submersion period. While significant differences were found between flow categories, there was no clear relationship between flow rate and persistence. The behaviour of the river samples was well-predicted by laboratory samples. 100 % fibre loss was never observed, with the maximum instead being 95.45 %. These results extend the understanding of fibre persistence on submerged substrates beyond the short submersion times in previous literature, and provide some deeper understanding of the impact of flow rate.

Lichen sclerosus of the oral mucosa: a hidden phenomenon.

Oral lichen sclerosus (OLS) represents a diagnostic challenge even for expert dermatologists due to its rarity and subtle clinical manifestations. Only few cases have been reported in literature to date. OLS typically presents with whitish macules in the oral cavity. Histopathological examination remains crucial for definitive diagnosis, with characteristic features including epithelial atrophy, subepithelial hyalinization, loss of elastic fibers, and lymphocytic infiltration. Management strategies vary depending on lesion size and symptomatic presentation, with topical or intralesional corticosteroids being the most commonly used treatment modalities. Long-term monitoring is recommended due to the potential for malignant transformation, although no cases have been reported to date. Greater awareness and understanding of OLS are essential for accurate diagnosis and effective management. Based on these findings, we recommend performing an accurate evaluation of the oral mucosa, especially when dealing with patients affected by genital or extragenital lichen sclerosus (LS). Moreover, we emphasize the importance of multidisciplinary collaboration between dermatologists and other specialists of oral disorders, such as dentists. This short review briefly summarizes available data on OLS, highlighting its diverse clinical presentations and diagnostic challenges. Despite its infrequent occurrence, OLS should be considered in the differential diagnosis of white macules in the oral cavity.

Anti-Resonant Hollow-Core Fibers with High Birefringence and Low Loss for Terahertz Propagation

A new type of anti-resonant hollow-core fiber for terahertz waveguides is proposed. By introducing central support pillars and an elliptical structure, the fiber achieves high birefringence while maintaining low confinement loss and low material absorption loss. The fiber structure is optimized through simulation using the finite element method. The optimized fiber exhibits a birefringence of up to 1.22 × 10−2 at a frequency of 1 THz, with a confinement loss of 8.34 × 10−6 dB/cm and a material absorption loss of 7.17 × 10−3 dB/cm. Furthermore, when the bending radius of the fiber is greater than 12 cm, the bending loss of the anti-resonant optical fiber at 1 THz is less than 1.36 × 10−4 dB/cm, demonstrating good bending resistance and high practical value. It is expected to play a significant role in optical communication systems.

Comparative analysis of high index core micro structured optical fibers (HIMSOF) and hollow core band gap fibers (HCBGF) performance efficiency in fiber communication system

Abstract This paper has clarified comparative analysis of high index core micro structured optical fibers (HIMSOF) and hollow core band gap fibers (HCBGF) performance efficiency in the fiber communication system. Total fiber dispersion is clarified versus distance between holes in µm at the employment of 850 nm, 1,300 nm and 1,550 nm wavelength transmission. Besides, the total fiber dispersion is also demonstrated against the hole diameter in µm at the employment of 850 nm, 1,300 nm and 1,550 nm wavelength transmission. The total fiber confinement loss is studied and illustrated against the distance between holes in µm at the employment of various wavelength band transmission. Total fiber losses are demonstrated in relation to the distance between holes in µm at the employment of 850 nm, 1,300 nm and 1,550 nm wavelength transmission.

The Challenge of E-Spinning Sub-Millimeter Tubular Scaffolds-A Design-of-Experiments Study for Fiber Yield Improvement.

In tissue engineering, electrospinning has gained significant interest due to its highly porous structure with an excellent surface area to volume ratio and fiber diameters that can mimic the structure of the extracellular matrix. Bioactive substances such as growth factors and drugs are easily integrated. In many applications, there is an important need for small tubular structures (I.D. < 1 mm). However, fabricating sub-millimeter structures is challenging as it reduces the collector area and increases the disturbing factors, leading to significant fiber loss. This study aims to establish a reliable and reproducible electrospinning process for sub-millimeter tubular structures with minimized material loss. Influencing factors were analyzed, and disturbance factors were removed before optimizing control variables through the design-of-experiments method. Structural and morphological characterization was performed, including the yield, thickness, and fiber arrangement of the scaffold. We evaluated the electrospinning process to enhance the manufacturing efficiency and reduce material loss. The results indicated that adjusting the voltage settings and polarity significantly increased the fiber yield from 8% to 94%. Variations in the process parameters also affected the scaffold thickness and homogeneity. The results demonstrate the complex relationship between the process parameters and provide valuable insights for optimizing electrospinning, particularly for the cost-effective and reproducible production of small tubular diameters.

Circulating netrin-1 levels are reduced and related to corneal nerve fiber loss in patients with diabetic neuropathy.

Deficiency of neurotropic factors is implicated in diabetic neuropathy (DN). Netrin-1 is a neurotropic factor, but its association with DN has not been explored. We have assessed the association between serum netrin-1 levels and early diabetic neuropathy assessed by quantifying corneal nerve fiber loss using corneal confocal microscopy. A total of 72 participants with type 2 diabetes, without and with corneal nerve fiber loss (DN- n = 42, DN+ n = 30), and 45 healthy controls were studied. Serum netrin-1 levels were measured by enzyme-linked immunosorbent assay, and corneal nerve morphology was assessed using corneal confocal microscopy. Corneal nerve fiber density, branch density, fiber length and serum netrin-1 levels were significantly lower in the DN- and DN+ groups compared with controls (P < 0.001). Netrin-1 levels correlated with corneal nerve fiber length in the DN+ group (r = 0.51; P < 0.01). A receiver operating characteristic curve analysis showed that a netrin-1 cut-off value of 599.6 (pg/mL) had an area under the curve of 0.85, with a sensitivity of 76% and specificity of 74% (P < 0.001; 95% confidence interval 0.76-0.94) for differentiating patients with and without corneal nerve loss. Serum netrin-1 levels show a progressive decline with increasing severity of small nerve fiber damage in patients with diabetes. Netrin-1 could act as a biomarker for small nerve fiber damage in DN.

Hybrid pumped laser sources based hybrid traveling wave SOA and optical EDFA amplifies for signal quality improvement

Abstract This paper has demonstrated the hybrid pumped laser sources based hybrid traveling wave SOA and optical EDFA amplifies for the signal quality improvement. The previous effective noise figure and fiber loss variations are clarified against wavelength band with/without amplification. The related previous signal output power versus Raman/EDFA pumped amplification and signal power conversion efficiency are indicated versus the launched pump power with the Raman/EDFA pumped amplification. The signal quality factor/BER against the transmission distance with/without amplification after receiver side. The modified amplified light signal power is demonstrated after 300 km distance SMF channel with wavelength band variations. The modified amplified light signal power is clarified after 300 km distance SMF channel by using optical power meter. The modified amplified light signal power is clarified after 300 km distance SMF channel with time band variations. The modified amplified electrical signal power is demonstrated after 350 km distance SMF channel with frequency band variations. The modified amplified electrical signal power is clarified after 350 km distance SMF channel with time band variations. The modified amplified electrical signal power is demonstrated after 350 km distance SMF channel by using electrical power meter.

Verified of leakage loss, birefringence, nonlinear parameters and total number of modes in silica/silica doped and plastic fibers for fiber system efficiency improvement

Abstract This paper has clarified verified of leakage loss, birefringence, nonlinear parameters and total number of modes in silica/silica doped and plastic fibers for fiber system efficiency improvement. The signal power loss is demonstrated with silica/silica doped/plastic fibers at various ambient temperatures. The estimated number of fiber modes is clarified in the core against silica/silica doped/plastic fiber core radius. The fiber birefringence is studied against silica/silica doped/plastic fiber core radius. The silica/silica doped/plastic fibers effective refractive index is clarified versus ambient temperature variations. The nonlinear parameter is demonstrated based silica doped fiber against the dopant concentration ratio with different temperature variations. The effective area cross section is studied based silica doped fiber against the dopant concentration ratio with different temperature variations. The predicted fiber loss is demonstrated against the fiber operating wavelength for silica glass fibers/silica doped fibers/plastic fibers. As well as the predicted fiber loss is clarified and studied versus fiber core radius for silica glass/silica doped/plastic fibers.

Neuroprotective effects of Si-based hydrogen-producing agent on 6-hydroxydopamine-induced neurotoxicity in juvenile mouse model

Neurotoxins have been extensively investigated, particularly in the field of neuroscience. They induce toxic damage, oxidative stress, and inflammation on neurons, triggering neuronal dysfunction and neurodegenerative diseases. Here we demonstrate the neuroprotective effect of a silicon (Si)-based hydrogen-producing agent (Si-based agent) in a juvenile neurotoxic mouse model induced by 6-hydroxydopamine (6-OHDA). The Si-based agent produces hydrogen in bowels and functions as an antioxidant and anti-inflammatory agent. However, the effects of the Si-based agent on neural degeneration in areas other than the lesion and behavioral alterations caused by it are largely unknown. Moreover, the neuroprotective effects of Si-based agent in the context of lactation and use during infancy have not been explored in prior studies. In this study, we show the neuroprotective effect of the Si-based agent on 6-OHDA during lactation period and infancy using the mouse model. The Si-based agent safeguards against the degradation and neuronal cell death of dopaminergic neurons and loss of dopaminergic fibers in the striatum (STR) and ventral tegmental area (VTA) caused by 6-OHDA. Furthermore, the Si-based agent exhibits a neuroprotective effect on the length of axon initial segment (AIS) in the layer 2/3 (L2/3) neurons of the medial prefrontal cortex (mPFC). As a result, the Si-based agent mitigates hyperactive behavior in a juvenile neurotoxic mouse model induced by 6-OHDA. These results suggest that the Si-based agent serves as an effective neuroprotectant and antioxidant against neurotoxic effects in the brain, offering the possibility of the Si-based agent as a neuroprotectant for nervous system diseases.

Ocular toxicity of daily anti-tubercular treatment regimen: A prospective observational study

Context: India carries a significant burden of TB which is the commonest cause of infectious disease-related mortality. Anti-tubercular drugs can cause serious ocular toxic effects. Optical coherence tomography (OCT) can be used as a valuable tool in the quantitative analysis of anti-tubercular treatment (ATT)-induced toxic optic neuropathy. Aims: To study the changes in visual parameters in patients on ATT and to analyze the OCT changes in patients by taking measurements once before initiation of treatment and once during ongoing treatment (between three and six months). Settings and Design: Tertiary care center, Prospective observational study. Methods and Material: A prospective observational study was conducted in 140 eyes of 70 subjects undergoing ATT as per the latest RNTCP guidelines where the following determinants were examined, and the corresponding values were taken once before initiation of treatment and once during ongoing treatment (between three and six months) and results were analyzed. Around 90% of the subjects were examined at the end fourth month. Visual acuity was taken using the Log Mar chart, color vision using Ishihara’s chart, and slit lamp examination and fundus evaluation using a 90 D lens. OCT was done and average nasal, temporal, superior, and inferior quadrant retinal nerve fiber layer (RNFL) measurements were taken. Perimetry was also done; however, findings were not included in this study. Statistical Analysis Used: Frequency and percentage were applied to study the changes in visual parameters in patients on ATT. A paired t-test was applied for numerical variables to analyze the OCT changes in patients undergoing ATT. A P value &lt; 0.05 was considered statistically significant. Results: Despite a near-normal appearance of the fundus on ophthalmoscopy, OCT clearly demonstrated and quantified the loss of retinal nerve fibers. Statistically significant RNFL thinning (P value &lt; 0.001) was noted in the superior, temporal, and inferior quadrants and least in the nasal quadrant (P = 0.005). Significant deterioration in visual acuity was observed following three months of ATT (P = 0.001). Red-green color vision abnormalities were detected in 14 out of 140 eyes (10%). Conclusions: RNFL thickness was reduced on OCT. RNFL thickness quantification and assessment of other visual parameters especially color vision help in the early diagnosis of ocular toxic effects of ATT. Hence, awareness and active screening are imperative in preventing visual impairment and blindness.

Development of a smart artificial muscle using optical fibres

A McKibben artificial muscle is a fluid-driven soft actuator comprising sleeve fibres and rubber tube. However, as typical bulky and rigid displacement sensors are unsuitable as sensor elements in soft actuators, displacement sensing is challenging for the McKibben artificial muscle. Therefore, we propose an optical fibre-based smart artificial muscle (OSAM) to estimate self-displacement from the bending loss of the optical fibre used as the sleeve fibre. The optical fibre can be effortlessly integrated into the OSAM sleeve using a braiding machine, which is generally used for manufacturing strings, easing the mass production process. The radius of curvature of the optical fibre changed when the OSAM was driven. The displacement of the artificial muscle was estimated based on the sensor output. To demonstrate the usefulness of OSAM, displacement feedback control experiments were conducted using the optical fibre sensor integrated into OSAM. From the results, OSAM’s displacement showed a good response to the target displacement. Therefore, the developed artificial muscle can facilitate displacement feedback control without requiring external sensors, which in turn can improve the performance of rehabilitation and wearable devices.

Frailty: Focus on Regenerative Medicine

Frailty, as a specific condition of increased vulnerability and deterioration of general health associated with aging in the elderly, is an emerging problem worldwide with serious implications for clinical practice and public health. Frailty increases the risk of falls, hospitalization, disability, and death. Muscle aging is associated with progressive loss of skeletal muscle mass and function. Loss of muscle mass with age can be related to muscle fiber atrophy and loss of muscle fibers. With increasing human age, remodeling of bone tissue becomes more prone to slow and steady loss of bone mass, which is primarily associated with loss of bone formation by osteoblasts. Recent preclinical and clinical studies have confirmed the safety of mesenchymal stem/stromal cells (MSCs) in the treatment of frailty. MSCs are attracted to sites of damage where they act to reduce inflammation and promote cell repair. Thus, there is an assumption that frailty can be treated with cell therapy