CaO-B2O3-SiO2 glass fibers for wound healing.

It was reported by Jung and Day in 2011 that a cotton-like glass fiber pad made of borate glass 13-93B3 demonstrated a remarkable wound healing effect. It was approved for sale as a novel wound dressing in the management of acute and chronic wounds in 2016. However, the detailed mechanism of its wound healing effect has not been reported. In the present study, glass fibers of different composition in the system CaO-B2O3-SiO2 were prepared and their in vitro properties investigated to determine the role of the constituent components in wound healing. Fine glass fibers that were 0.6-2.0 µm in diameter were obtained by a melt blown method. However, these fibers were accompanied by small glass beads because of the low viscosity of the glass melts. 13-93B3 glass released an appreciable amount of borate and calcium ions into simulated body fluid (SBF). The amounts of these released ions decreased with partial replacement of the B2O3 in 13-93B3 with SiO2. The addition of large amounts of the borate and calcium ions into the culture medium decreased the viability of the L929 fibroblasts. Partial replacement of the B2O3 in 13-93B3 with SiO2 induced the formation of an apatite-like phase amenable to the adsorption of biological components on its surface in SBF. The wound healing effect of these glass fibers of different composition is worth examining in future animal experiments.

Forced expression of miR-143 and -145 in cardiomyocytes induces cardiomyopathy with a reductive redox shift.

BACKGROUND: Animal model studies show that reductive stress is involved in cardiomyopathy and myopathy, but the exact physiological relevance remains unknown. In addition, the microRNAs miR-143 and miR-145 have been shown to be upregulated in cardiac diseases, but the underlying mechanisms associated with these regulators have yet to be explored. METHODS: We developed transgenic mouse lines expressing exogenous miR-143 and miR-145 under the control of the alpha-myosin heavy chain (αMHC) promoter/enhancer. RESULTS: The two transgenic lines showed dilated cardiomyopathy-like characteristics and early lethality with markedly increased expression of miR-143. The expression of hexokinase 2 (HK2), a cardioprotective gene that is a target of miR-143, was strongly suppressed in the transgenic hearts, but the in vitro HK activity and adenosine triphosphate (ATP) content were comparable to those observed in wild-type mice. In addition, transgenic complementation of HK2 expression did not reduce mortality rates. Although HK2 is crucial for the pentose phosphate pathway (PPP) and glycolysis, the ratio of reduced glutathione (GSH) to oxidized glutathione (GSSG) was unexpectedly higher in the hearts of transgenic mice. The expression of gamma-glutamylcysteine synthetase heavy subunit (γ-GCSc) and the in vitro activity of glutathione reductase (GR) were also higher, suggesting that the recycling of GSH and its de novo biosynthesis were augmented in transgenic hearts. Furthermore, the expression levels of glucose-6-phosphate dehydrogenase (G6PD, a rate-limiting enzyme for the PPP) and p62/SQSTM1 (a potent inducer of glycolysis and glutathione production) were elevated, while p62/SQSTM1 was upregulated at the mRNA level rather than as a result of autophagy inhibition. Consistent with this observation, nuclear factor erythroid-2 related factor 2 (Nrf2), Jun N-terminal kinase (JNK) and inositol-requiring enzyme 1 alpha (IRE1α) were activated, all of which are known to induce p62/SQSTM1 expression. CONCLUSIONS: Overexpression of miR-143 and miR-145 leads to a unique dilated cardiomyopathy phenotype with a reductive redox shift despite marked downregulation of HK2 expression. Reductive stress may be involved in a wider range of cardiomyopathies than previously thought.

Effect of Using a Cardiac Catheterization Table-Stabilizing Stick on the Quality of Cardiopulmonary Resuscitation in the Cardiac Catheterization Laboratory: A Simulation-Based Study.

Rapid defibrillation and high-quality cardiopulmonary resuscitation (CPR) are necessary for patients with cardiopulmonary arrest, one of the most serious and frequently encountered complications in cardiac catheterization laboratories. However, when the catheterization table is withdrawn from its neutral position for fluoroscopy, it is unstable and unsuitable for resuscitation because of its cantilever structure. To stabilize the table in its withdrawn position, the use of a table-stabilizing stick might improve CPR quality. To investigate the effect of using a cardiac catheterization table-stabilizing stick on CPR quality, a CPR simulation mannequin was placed on a cardiac catheterization table that was withdrawn from the C-arm of the X-ray machine. CPR quality was assessed with or without the use of a table-stabilizing stick under the table. The CPR quality assessment (Q-CPR) scores were 79.6 ± 11.4% using the table-stabilizing stick and 47.7 ± 30.3% without the use of the stick device (p = 0.02). In this simulation-based study, the use of a table-stabilizing stick in a cardiac catheterization table withdrawn from the C-arm of the X-ray machine improved the quality of CPR.

Tetherin antagonism by V proteins is a common trait among the genus Rubulavirus.

Tetherin (BST-2/CD317/HM1.24) is an anti-viral factor that restricts the budding of several enveloped viruses. Most of these viruses have evolved to encode tetherin antagonists. Our previous study demonstrated that the growth of human parainfluenza virus type 2 (hPIV-2), a member of the genus Rubulavirus in the family Paramyxoviridae, was inhibited by tetherin, and its V protein decreases the amount of cell surface tetherin by the interaction. In the present study, we investigated whether tetherin inhibits the growth of other rubulaviruses including PIV-5, mumps virus (MuV), simian virus 41, and hPIV-4, and whether their V proteins act as tetherin antagonists. Plaque assay demonstrated that the growth of PIV-5 and MuV was inhibited by tetherin. Flow cytometry and immunoblot analyses revealed that the infection of PIV-5 and MuV caused reduction of cell surface tetherin without affecting total amount of tetherin. Immunoprecipitation analysis showed that all V proteins of rubulaviruses tested bound to tetherin. These results suggest that tetherin antagonism by V proteins is common among the genus Rubulavirus.

The Fusion Protein Specificity of the Parainfluenza Virus Hemagglutinin-Neuraminidase Protein Is Not Solely Defined by the Primary Structure of Its Stalk Domain.

UNLABELLED: Virus-specific interaction between the attachment protein (HN) and the fusion protein (F) is prerequisite for the induction of membrane fusion by parainfluenza viruses. This HN-F interaction presumably is mediated by particular amino acids in the HN stalk domain and those in the F head domain. We found in the present study, however, that a simian virus 41 (SV41) F-specific chimeric HPIV2 HN protein, SCA, whose cytoplasmic, transmembrane, and stalk domains were derived from the SV41 HN protein, could not induce cell-cell fusion of BHK-21 cells when coexpressed with an SV41 HN-specific chimeric PIV5 F protein, no. 36. Similarly, a headless form of the SV41 HN protein failed to induce fusion with chimera no. 36, whereas it was able to induce fusion with the SV41 F protein. Interestingly, replacement of 13 amino acids of the SCA head domain, which are located at or around the dimer interface of the head domain, with SV41 HN counterparts resulted in a chimeric HN protein, SCA-RII, which induced fusion with chimera no. 36 but not with the SV41 F protein. More interestingly, retroreplacement of 11 out of the 13 amino acids of SCA-RII with the SCA counterparts resulted in another chimeric HN protein, IM18, which induced fusion either with chimera no. 36 or with the SV41 F protein, similar to the SV41 HN protein. Thus, we conclude that the F protein specificity of the HN protein that is observed in the fusion event is not solely defined by the primary structure of the HN stalk domain. IMPORTANCE: It is appreciated that the HN head domain initially conceals the HN stalk domain but exposes it after the head domain has bound to the receptors, which allows particular amino acids in the stalk domain to interact with the F protein and trigger it to induce fusion. However, other regulatory roles of the HN head domain in the fusion event have been ill defined. We have shown in the current study that removal of the head domain or amino acid substitutions in a particular region of the head domain drastically change the F protein specificity of the HN protein, suggesting that the ability of a given HN protein to interact with an F protein is defined not only by the primary structure of the HN stalk domain but also by its conformation. This notion seems to account for the unidirectional substitutability among rubulavirus HN proteins in triggering noncognate F proteins.

CD98hc regulates the development of experimental colitis by controlling effector and regulatory CD4(+) T cells.

CD4(+) T cell activation is controlled by signaling through the T cell receptor in addition to various co-receptors, and is also affected by their interactions with effector and regulatory T cells in the microenvironment. Inflammatory bowel diseases (IBD) are caused by the persistent activation and expansion of auto-aggressive CD4(+) T cells that attack intestinal epithelial cells. However, the molecular basis for the persistent activation of CD4(+) T cells in IBD remains unclear. In this study, we investigated how the CD98 heavy chain (CD98hc, Slc3a2) affected the development of colitis in an experimental animal model. Transferring CD98hc-deficient CD4(+)CD25(-) T cells into Rag2(-/-) mice did not cause colitis accompanied by increasing Foxp3(+) inducible regulatory T cells. By comparison, CD98hc-deficient naturally occurring regulatory T cells (nTregs) had a decreased capability to suppress colitis induced by CD4(+)CD25(-) T cells, although CD98hc-deficient mice did not have a defect in the development of nTregs. Blocking CD98hc with an anti-CD98 blocking antibody prevented the development of colitis. Our results indicate that CD98hc regulates the expansion of autoimmune CD4(+) T cells in addition to controlling nTregs functions, which suggests the CD98hc as an important target molecule for establishing strategies for treating colitis.

Full conversion of the hemagglutinin-neuraminidase specificity of the parainfluenza virus 5 fusion protein by replacement of 21 amino acids in its head region with those of the simian virus 41 fusion protein.

For most parainfluenza viruses, a virus type-specific interaction between the hemagglutinin-neuraminidase (HN) and fusion (F) proteins is a prerequisite for mediating virus-cell fusion and cell-cell fusion. The molecular basis of this functional interaction is still obscure partly because it is unknown which region of the F protein is responsible for the physical interaction with the HN protein. Our previous cell-cell fusion assay using the chimeric F proteins of parainfluenza virus 5 (PIV5) and simian virus 41 (SV41) indicated that replacement of two domains in the head region of the PIV5 F protein with the SV41 F counterparts bestowed on the PIV5 F protein the ability to induce cell-cell fusion on coexpression with the SV41 HN protein while retaining its ability to induce fusion with the PIV5 HN protein. In the study presented here, we furthered the chimeric analysis of the F proteins of PIV5 and SV41, finding that the PIV5 F protein could be converted to an SV41 HN-specific chimeric F protein by replacing five domains in the head region with the SV41 F counterparts. The five SV41 F-protein-derived domains of this chimera were then divided into 16 segments; 9 out of 16 proved to be not involved in determining its specificity for the SV41 HN protein. Finally, mutational analyses of a chimeric F protein, which harbored seven SV41 F-protein-derived segments, revealed that replacement of at most 21 amino acids of the PIV5 F protein with the SV41 F-protein counterparts was enough to convert its HN protein specificity.

Association between the experience of exertional heat illness (EHI) and living conditions of collegiate student athletes.

Exertional heatstroke (EHS), a severe form of exertional heat illness (EHI), is the third leading cause of death in athletes; thus, early detection and prevention of EHI can help prevent EHS, which is a life-threatening condition. This study aimed to clarify the association between the cognizance of experiencing EHI and living conditions and specific EHI symptoms among collegiate athletes. This study was conducted in October 2022 by administering a questionnaire to 237 male collegiate athletes. Of the 215 (90.7%) respondents, 197 (91.6%) provided valid responses; among them, 88 (44.7%) responded they had experienced EHI, while 109 (55.3%) had not. A history of medical examinations due to EHI, having experienced headaches during summer activities, and having read the EHI manual were factors indicating cognizance of EHI. The number of times meals containing a staple food, main dish, and side dish were eaten in a day was a factor in preventing EHI. Early detection of EHI is important for its prevention, and it is important that athletes themselves have knowledge of symptoms and can correctly self-diagnose EHI. Emphasizing the potential of a well-balanced dietary intake has the potential to prevent EHI is crucial.

Factors Influencing Willingness to Undergo Lung Cancer Screening in the Future: A Cross-Sectional Study of Japanese University Students.

Lung cancer (LC) is currently the leading cause of cancer deaths in Japan. Early detection through lung cancer screening (LCS) is important for reducing mortality. Therefore, exploring the factors affecting willingness to undergo LCS, particularly among young people, is important. This study aimed to elucidate the inclination toward LCS and its determining factors among Japanese university students. This cross-sectional study, involving 10,969 Japanese university students, was conducted in April 2023. A Pearson's chi-square test and a binomial logistic regression analysis were used to analyze factors related to the dependent variable, willingness to undergo LCS in the future. Out of the 6779 participants (61.8%) involved in this study, 6504 (95.9%) provided valid responses, and 4609 (70.9%) expressed a willingness to undergo LCS in the future. Analysis revealed current smoking as a barrier to future willingness to undergo LCS. Other barriers included postponing the age of screening, anxiety about the screening content, and concerns about the possibility of having cancer after screening. Addressing barriers, such as current smoking and anxiety about screening, that prevent young people from undergoing LCS in the future is crucial. Therefore, universities should provide opportunities to educate students about LCS and explore various educational methods.

Enhancement of in vitro antibacterial activity and bioactivity of iodine-loaded titanium by micro-scale regulation using mixed-acid treatment.

Postoperative infection and subsequent device loss are serious complications in the use of titanium dental implants and plates for jawbone reconstruction. We have previously reported that NaOH-CaCl2 -thermal-ICl3 -treated titanium (NaCaThIo) has a nano-scale surface and exhibits antibacterial activity against Staphylococcus aureus. The present study examined the surface properties of mixed-acid treated and then iodine-treated titanium (MA-NaCaThIo), and evaluated oral antibacterial activity and cytotoxicity compared with the results obtained with NaCaThIo. MA-NaCaThIo formed a surface layer with a nano-scale network structure having microscale irregularities, and both the thickness of the surface layer (1.49 ± 0.16 µm) and the average surface roughness (0.35 ± 0.03 µm) were significantly higher than those of NaCaThIo. Furthermore, MA-NaCaThIo maintained high hydrophilicity with a contact angle of 7.5 ± 1.7° even after 4 weeks, as well as improved apatite formation, iodine ion release, and antibacterial activity against Prevotella intermedia compared to NaCaThIo. Cell culture test revealed that MA-NaCaThIo exhibited no cytotoxicity against MG-63 and Vero cells, while increased cell proliferation, ALP activity and mineralization of MG-63 compared to NaCaThIo. This treated titanium is expected to be useful for the development of next-generation titanium devices having both bone-bonding and antibacterial properties.

Mechanical, bioactive, and long-lasting antibacterial properties of a Ti scaffold with gradient pores releasing iodine ions.

The ideal bone implant would effectively prevent aseptic as well as septic loosening by minimizing stress shielding, maximizing bone ingrowth, and preventing implant-associated infections. Here, a novel gradient-pore-size titanium scaffold was designed and manufactured to address these requirements. The scaffold features a larger pore size (900 µm) on the top surface, gradually decreasing to small sizes (600 µm to 300 µm) towards the center, creating a gradient structure. To enhance its functionality, the additively manufactured scaffolds were biofunctionalized using simple chemical and heat treatments so as to incorporate calcium and iodine ions throughout the surface. This unique combination of varying pore sizes with a biofunctional surface provides highly desirable mechanical properties, bioactivity, and notably, long-lasting antibacterial activity. The target mechanical aspects, including low elastic modulus, high compression, compression-shear, and fatigue strength, were effectively achieved. Furthermore, the biofunctional surface exhibits remarkable in vitro bioactivity and potent antibacterial activity, even under conditions specifically altered to be favorable for bacterial growth. More importantly, the integration of small pores alongside larger ones ensures a sustained high release of iodine, resulting in antimicrobial activity that persisted for over three months, with full eradication of the bacteria. Taken together, this gradient structure exhibits obvious superiority in combining most of the desired properties, making it an ideal candidate for orthopedic and dental implant applications.

[A new radiographic technique for detecting avulsion fracture of the lateral malleolus in children].

The objectives of this study were to determine the usefulness of a newly-developed distal fibular axial view radiography modified method for depicting avulsion fracture of the lateral malleolus in children from a functional anatomy viewpoint. Conventional radiography was applied to sixty-nine avulsion fracture suspected ankles of 67 children. Average age and standard deviation at injury were 8.00 and 1.46, respectively. We compared the ability of the modified method to detect avulsion fractures of the lateral malleolus with those could not be depicted using the conventional method, and noted that 42 avulsion fractures (60.9%) could be depicted using the conventional method. We applied the modified method to 27 joints that the conventional method had diagnosed as normal. Of these, the modified method detected 13 avulsion fractures (48.1%). In conclusion, the modified radiography method made it possible to depict avulsion fracture of the lateral malleolus in cases that resisted detection by the conventional method.

Factors affecting health-related quality of life among firefighters during the COVID-19 pandemic: A single-center study.

During the coronavirus disease 2019 (COVID-19) outbreak, firefighters have been working in an environment that is both physically and mentally taxing. This study aimed to investigate factors affecting health-related quality of life (HRQOL) among firefighters in Japan during the COVID-19 pandemic. A total of 227 firefighters from a single firefighting organization were surveyed in June 2021, during the fourth infection spread period of COVID-19 in Japan. Regression analysis was performed to examine factors affecting HRQOL of firefighters measured with the SF-8. In the present study, factors affecting HRQOL among firefighters during the COVID-19 pandemic were lack of sleep, physical abnormalities due to infection control measures, exercise habits, living with family members, and history of suspected COVID-19 infection. The present findings may help develop support services for first responders, including firefighters during the COVID-19 pandemic.

Nicotine Dependence among College Students Uninterested in Smoking Cessation during the COVID-19 Pandemic: A Cross-Sectional Survey.

This study investigated nicotine dependence among Japanese university students who had reached the smoking age (20 years or older) by the time of the coronavirus disease 2019 (COVID-19) pandemic and examined factors that encourage early smoking cessation. Social dependence on nicotine was evaluated using the Kano Total Social Nicotine Dependence Level (KTSND), and physiological dependence was evaluated using the Fagerström Nicotine Dependence Index (FTND). Of the 356 college students who smoked (4.4% of the total), 182 (51.1%) stated that they were not interested in quitting. Furthermore, 124 (68.1%) of those with no interest in quitting smoking were aware that smoking is a high-risk factor for COVID-19, and 58 (31.9%) were unaware. The group not aware of this risk had significantly higher KTSND scores than the group aware of it. The examination of cigarette type that indicated the users of non-conventional cigarette products and dual-user groups scored significantly higher than the cigarette group on FTND items. Overall, the smokers scored above the normal range for social nicotine dependence, suggesting the need to reduce nicotine dependence to encourage college students who continue to smoke to quit smoking.

University students' living conditions during the COVID-19 pandemic and predictors of their subjective health views: A cross-sectional survey.

This study aimed to explore the factors influencing subjective health views based on the living conditions and concerns of university students during the coronavirus infection 2019 (COVID-19) pandemic. From March to April 2021, a questionnaire survey was administered to 8,547 Japanese university students, and logistic regression analysis was used to explore factors related to subjective health views. The results showed that satisfaction with quality of sleep (OR = 2.651, 95% Cl 2.370-2.966,p < 0.001), satisfaction with university life (OR = 2.486, 95%Cl 2.215-2.789, p < 0.001), satisfaction with diet (OR = 1.849, 95% CI: 1.496-2.285, p < 0.001), regular exercise (OR = 1.759, 95% CI: 1.594-1.941, p < 0.001), consciousness of nutritional balance (OR = 1.276, 95% CI: 1.147-1.420,p < 0.001), eating breakfast every day (OR = 1.247, 95% CI: 1.121-1.387, p < 0.001), and consuming soft drinks at least once a week (OR = 0.865, 95% CI: 0.755-0.966, p = 0.010) were positive factors for subjective views of health. On the other hand, anxiety about whether the necessary credits can be obtained (OR = 0.885, 95% CI: 0.799-0.980, p = 0.019), infection from minimal outings (OR = 0.881, 95% CI: 0.794-0.976, p = 0.016) building and maintaining friendships on campus (OR = 0.867, 95% CI: 0.767-0.980, p = 0.023), and being able to continue working (OR = 0.713, 95% CI: 0.640-0.795, p < 0.001) were identified as negative factors. To ensure a healthy university life during the COVID-19 pandemic or future pandemic, supports tailored to students' living conditions and measures to address their anxieties are required.

Identification of domains on the fusion (F) protein trimer that influence the hemagglutinin-neuraminidase specificity of the f protein in mediating cell-cell fusion.

For most paramyxoviruses, virus type-specific interaction between fusion (F) protein and attachment protein (hemagglutinin-neuraminidase [HN], hemagglutinin [H], or glycoprotein [G]) is a prerequisite for mediating virus-cell fusion and cell-cell fusion. Our previous cell-cell fusion assay using the chimeric F proteins of human parainfluenza virus 2 (HPIV2) and simian virus 41 (SV41) suggested that the middle region of the HPIV2 F protein contains the site(s) that determines its specificity for the HPIV2 HN protein. In the present study, we further investigated the sites of the F protein that could be critical for determining the HN protein specificity. By analyzing the reported structure of the F protein of parainfluenza virus 5 (PIV5), we found that four major domains (M1, M2, M3, and M4) and five minor domains (A to E) in the middle region of the PIV5 F protein were exposed on the trimer surface. We then replaced these domains with the SV41 F counterparts individually or in combination and examined whether the resulting chimeras could mediate cell-cell fusion when coexpressed with the SV41 HN protein. The results showed that a chimera designated M(1+2), which harbored SV41 F-derived domains M1 and M2, mediated cell-cell fusion with the coexpressed SV41 HN protein, suggesting that these domains are involved in determining the HN protein specificity. Intriguingly, another chimera which harbored the SV41 F-derived domain B in addition to domains M1 and M2 showed increased specificity for the SV41 HN protein compared to that of M(1+2), although it was capable of mediating cell-cell fusion by itself.

Human parainfluenza virus type 2 L protein regions required for interaction with other viral proteins and mRNA capping.

The large RNA polymerase (L) protein of human parainfluenza virus type 2 (hPIV2) binds the nucleocapsid, phosphoprotein, and V protein, as well as itself, and these interactions are essential for transcription and replication of the viral RNA genome. Although all of these interactions were found to be mediated through the domains within the N terminus of L, the C terminus of the L protein was also required for minigenome reporter gene expression. We have identified a highly conserved rubulavirus domain near the C terminus of the L protein that is required for mRNA synthesis but not for genome replication. Remarkably, this region of L shares homology with a conserved region of cellular capping enzymes that binds GTP and forms a lysyl-GMP enzyme intermediate, the first step in the cellular capping reaction. We propose that this conserved region of L also binds GTP (or GDP) to carry out the second step of the unconventional nonsegmented negative-strand virus capping reaction.

The role of CD98hc in mouse macrophage functions.

CD98hc is a type II transmembrane protein that covalently links to one of several L-type amino acid transporters. CD98hc was first identified as a lymphocyte activation marker. In this study, we examined the role that CD98hc plays in the functions of macrophages using tissue specific knock-out miceCD98hc (CD98hc(flox/-)LysM-cre mice). When isolated peritoneal macrophages were incubated for 48 h, the macrophages obtained from the knock-out mice showed round-shaped morphologies, while almost all of the cells obtained from the control mice were spindle-shaped. The macrophage functions such as the antigen-presenting, phagocytic, and fusion activities, have been reported to decrease in CD98hc-deficient peritoneal macrophages. In addition, when the CD98hc deficient macrophages were stimulated with either IFN-γ/LPS or IL-4, the production of NO(2) or arginase-I decreased in comparison to that observed in the control macrophages. These findings show that the CD98hc molecules play an important role in the activation and functions of macrophages.

Cross-infection risks of SARS-CoV-2 while playing catch using a baseball: Creating a safe sporting environment during the COVID-19 pandemic.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of the coronavirus disease (COVID-19), is found primarily in the respiratory tract secretions of infected individuals with one of the main routes of transmission being direct or indirect contact. In this study, using fluorescent paint, we evaluated the spread of contaminants while playing catch with a baseball. Fluorescent paint was applied to the right hand of a right-handed baseball player who then engaged in playing catch with 10 other right-handed players (partners) for 5 min each. The fluorescent paint was detected on the right hands (inside) and gloves (inside) of all the 10 partners as well as on the ball; in some partners it was also detected on the back of the right hands or the back of the gloves. However, except for their right hands, fluorescent paint was not detected on the surface of the bodies of the partners. These observations indicated that the fluorescent paint (mimicking virus-containing contaminants) on the hand spreads very efficiently from person to person during the throwing and catching of a baseball, suggesting that a thorough and frequent disinfection of the hands and equipment is important in the prevention of infections that may occur while playing baseball.

Reliability and validity of lower limb joint range of motion measurements using a smartphone.

This study aimed to examine the reliability and validity of using a smartphone to measure the multi-joint range of motion of the lower limbs. We measured the straight leg raise angle, ankle dorsiflexion angle, and hip internal rotation angle in each of the 40 lower extremities of 20 healthy adults. Measurements were compared between a conventional method using a goniometer and a smartphone application method. The intraclass correlation coefficient (ICC) was used to evaluate the reliability of each smartphone measurement, and Bland-Altman analysis was used to examine measurement errors. The criterion-related validity of the two methods was also examined. Intra-rater reliability (ICC 0.668-0.939) was substantial to almost perfect, with no systematic errors found for all items, and the standard errors of measurement were acceptable. Inter-rater reliability (ICC 0.701-0.936) was also substantial to almost perfect, but the straight leg raise angle and hip internal rotation angle showed fixation errors. For these two measurements, with more than one examiner, the limit of agreement of error needs to be considered. No systematic errors were found in the ankle dorsiflexion angle, and the standard error of measurement was within the acceptable range. A moderate to strong correlation (r = 0.626-0.915) was found between the conventional and smartphone methods, demonstrating good criterion-related validity. However, in the ankle dorsiflexion angle measurements, the reliability and validity were shown to be lower than the other two items. This suggested the necessity of changing the measurement conditions in order to use the ankle dorsiflexion angle in clinical practice.