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Successful treatment of neurodegenerative diseases (NDDs), including Alzheimer’s disease (AD), Parkinson’s disease (PD), and Huntington’s disease (HD), remains a significant challenge for neurologists due to the undesirable curative outcomes. Apart from surgeries, most drugs are only used to relieve the patients’ symptoms without a permanent cure of the disease. The development of novel biomaterials targeting NDDs is greatly hindered by the limited understanding of underlying molecular mechanisms. Considering the difficulties in NDD drug development and clinical trials, a comprehensive and up-to-date review of disease pathogenesis and related novel therapies are needed. In the current article, the basic concepts and pathogenic characteristics of NDDs are firstly illustrated. Following the detailed description of molecular mechanisms underlying three common NDDs, recent advances of drug development based on targeting different pathogenic mechanisms are clarified. Hopefully, this review will be beneficial to address the gap between materials and targeted mechanisms while simultaneously provide suggestions for the future design of precise NDD medicine.

Ischemic stroke is still a serious threat to human life and health, but there are few therapeutic options available to treat stroke because of limited blood-brain penetration. The development of nanotechnology may overcome some of the problems related to traditional drug development. In this review, we focus on the potential applications of nanotechnology in stroke. First, we will discuss the main molecular pathological mechanisms of ischemic stroke to develop a targeted strategy. Second, considering the important role of the blood-brain barrier in stroke treatment, we also delve mechanisms by which the blood-brain barrier protects the brain, and the reasons why the therapeutics must pass through the blood-brain barrier to achieve efficacy. Lastly, we provide a comprehensive review related to the application of nanomaterials to treat stroke, including liposomes, polymers, metal nanoparticles, carbon nanotubes, graphene, black phosphorus, hydrogels and dendrimers. To conclude, we will summarize the challenges and future prospects of nanomedicine-based stroke treatments., Graphical abstract Image 1, Highlights • Discussed the main molecular pathological mechanisms of ischemic stroke. • Reviewed several treatments for stroke. • Discussed the blood-brain barrier in detail.Summarized the applications of various nanomaterials in stroke. • Summarized the challenges and future prospects of nanomedicine-based stroke treatment.

Photodynamic therapy (PDT) is a non-invasive or minimally-invasive treatment which applies photosensitizers (PSs) to create reactive oxygen species (ROS) exposed to light trigger to destroy cancer cells. PDT can activate host anti-tumor immune responses but not powerful enough to kill metastatic tumors. Because of its carrier advantage, imaging, and therapeutic function together with enhanced permeability and retention (EPR) effect, nano-materials have already been used in photo-immunotherapy. Herein, photodynamic immunotherapy (PDIT) based on nanotechnology seems to be a hopeful new form of cancer therapy. In this article, we firstly summarize the recent development in photodynamic immunotherapy based on nanotechnology.

In recent years, two-dimensional (2D) black phosphorus (BP) has been widely applied in many fields, such as (opto)electronics, transistors, catalysis and biomedical applications due to its large surface area, tunable direct bandgap, superior charge carrier mobility, and unique in-plane anisotropic structure. To exploit its full potential and push the limits, studies on functional 2D BP nanostructures fabricated by a variety of methods, such as surface functionalization and hybridization, are rapidly expanding for next-generation devices with unprecedented properties. In this review, firstly, the synthetic techniques and fundamental properties of functional 2D BP nanostructures, including surface-modified 2D BP nanostructures and mixed-dimensional 2D BP-based heterostructures, are systematically summarized. Secondly, the recent progress of functional 2D BP nanostructures in the fields of energy storage and conversion, (opto) electronics, catalysis, sensors, nonlinear photonics, and biomedical applications is highlighted. Last but not least, the challenges and future opportunities in these emerging areas are discussed. We hope that this review can provide fundamental guidance on new designs of high-performance functional 2D BP nanostructures to meet the growing demand of next-generation devices.

Photodynamic therapy (PDT) has been extensively investigated for decades for tumor treatment because of its non-invasiveness, spatiotemporal selectivity, lower side-effects, and immune activation ability. It can be a promising treatment modality in several medical fields, including oncology, immunology, urology, dermatology, ophthalmology, cardiology, pneumology, and dentistry. Nevertheless, the clinical application of PDT is largely restricted by the drawbacks of traditional photosensitizers, limited tissue penetrability of light, inefficient induction of tumor cell death, tumor resistance to the therapy, and the severe pain induced by the therapy. Recently, various photosensitizer formulations and therapy strategies have been developed to overcome these barriers. Significantly, the introduction of nanomaterials in PDT, as carriers or photosensitizers, may overcome the drawbacks of traditional photosensitizers. Based on this, nanocomposites excited by various light sources are applied in the PDT of deep-seated tumors. Modulation of cell death pathways with co-delivered reagents promotes PDT induced tumor cell death. Relief of tumor resistance to PDT with combined therapy strategies further promotes tumor inhibition. Also, the optimization of photosensitizer formulations and therapy procedures reduces pain in PDT. Here, a systematic summary of recent advances in the fabrication of photosensitizers and the design of therapy strategies to overcome barriers in PDT is presented. Several aspects important for the clinical application of PDT in cancer treatment are also discussed.

Objective: We sought to determine the long-term bioavailability of single doses of intramuscular (IM) vita-min D2 (D2) in healthy adults. Methods: Forty healthy volunteers with hypovitaminosis D received a single dose of 200,000, 400,000, or 600,000 IU intramuscular D2 or no treatment. Levels of 25-hydroxyvitamin D2 (25lOH]D2) and 25-hydroxyvitamin D3 (25lOH]D3) in serum were measured by liquid chromatography-tandem mass spectrometry. Vitamin D binding protein (DBP) and intact parathyroid hormone (iPTH), bone turnover markers (BTMs), and serum and urinary calcium were also measured. Results: After a single dose of D2 injection, the level of 25(OH)D2 increased slowly and reached a plateau at 8 weeks. The plateau remained stable for 12 weeks. The mean increase in 25(OH)D2 was 6.8, 9.6, or 15.6 ng/mL after injection of 200,000 IU, 400,000 IU, or 600,000 IU D2. Although endogenous 25(OH)D3 levels were reduced by IM D2, the total 25(OH)D levels increased by 5.0, 7.0, or 10.3 ng/mL in average after injection of 200,000 IU, 400,000 IU, or 600,000 IU D2. The iPTH levels were also decreased by IM D2. However, levels of serum calcium, BTMs, and DBP and urinary calcium were not altered by IM D2. Conclusion: A single dose of 200,000 IU, 400,000 IU, or 600,000 IU IM D2 raises total 25-hydroxyvitamin D levels by 5.0, 7.0, or 10.3 ng/mL on average for at least 12 weeks and reduces iPTH and endogenous 25(OH)D3 levels without affecting levels of serum calcium, BTMs, DBP, and urinary calcium.

Industrial production, environmental monitoring, and clinical medicine put forward urgent demands for high-performance gas sensors. Two-dimensional (2D) materials are regarded as promising gas-sensing materials owing to their large surface-to-volume ratio, high surface activity, and abundant surface-active sites. However, it is still challenging to achieve facilely prepared materials with high sensitivity, fast response, full recovery, and robustness in harsh environments for gas sensing. Here, a combination of experiments and density functional theory (DFT) calculations is performed to explore the application of tellurene in gas sensors. The prepared tellurene nanoflakes via facile liquid-phase exfoliation show an excellent response to NO2 (25 ppb, 201.8% and 150 ppb, 264.3%) and an ultralow theory detection limit (DL) of 0.214 ppb at room temperature, which is excellent compared to that of most reported 2D materials. Furthermore, tellurene sensors present a fast response (25 ppb, 83 s and 100 ppb, 26 s) and recovery (25 ppb, 458 s and 100 ppb, 290 s). The DFT calculations further clarify the reasons for enhanced electrical conductivity after NO2 adsorption because of the interfacial electron transfer from tellurene to NO2, revealing an underlying explanation for tellurene-based gas sensors. These results indicate that tellurene is eminently promising for detecting NO2 with superior sensitivity, favorable selectivity, an ultralow DL, fast response-recovery, and high stability.

Despite the large number of osteoporosis patients in China, the diagnosis and treatment rates remain low. The Fracture Risk Assessment Tool (FRAX) can be used to effectively evaluate fracture risk. In this study, we explored the Chinese-specific thresholds of FRAX without the T-score. In all, 264 postmenopausal women aged > 50 years were randomly recruited from community-medical centers. All subjects completed self-reported questionnaires, BMD measurements, and spinal radiographs. The 10-year hip and major osteoporotic fracture risks were calculated by FRAX. A new threshold for both 10-year hip and major osteoporotic fracture risk was explored with receiver operating characteristic (ROC) curve analysis. Overall, 92 subjects were diagnosed with osteoporosis. Among them, 14 participants with T-score > − 2.5 were diagnosed with osteoporosis based on clinical fractures. ROC analysis showed the cut-off value of the 10-year hip osteoporotic fracture for detecting osteoporosis was 0.95%, while that of 10-year major osteoporotic fracture was 4.95%. The sensitivity and specificity of the 10-year hip osteoporotic fracture probability for detecting osteoporosis were 0.86 and 0.59, respectively, while the guideline-recommended threshold had a sensitivity of 0.49 and specificity of 0.83. The sensitivity and specificity of the 10-year major osteoporotic fractures with the new threshold were 0.76 and 0.69, respectively, while the recommended threshold had a sensitivity of 0 and specificity of 1. Current guideline-recommended FRAX thresholds without BMD showed low sensitivity. Therefore, 10-year osteoporotic hip fracture probability ≥ 0.95% and 10-year osteoporotic major fracture probability ≥ 4.95% are recommended as the new thresholds.

In recent years, nanomaterials and nanotechnology have emerged as vital factors in the medical field with a unique contribution to cancer medicine. Given the increasing number of cancer patients, it is necessarily required to develop innovative strategies and therapeutic modalities to tackle hypoxia, which forms a hallmark and great barrier in treating solid tumors. The present review details the challenges in nanotechnology-based hypoxia, targeting the strategies and solutions for better therapeutic performances. The interaction between hypoxia and tumor is firstly introduced. Then, we review the recently developed engineered nanomaterials towards multimodal hypoxia tumor therapies, including chemotherapy, radiotherapy, and sonodynamic treatment. In the next part, we summarize the nanotechnology-based strategies for overcoming hypoxia problems. Finally, current challenges and future directions are proposed for successfully overcoming the hypoxia tumor problems.

Wonderful black phosphorus (BP) and some BP analogs (BPAs) have been increasingly studied for their biomedical applications owing to their fascinating properties and biodegradability, but opportunities and challenges have always coexisted in their study. Poor stability upon exposure to the natural environment is the major obstacle hampering their in vivo applications. BP/polymer and BPAs/polymer nanocomposites can not only efficiently prevent their oxidation and aggregation but also exhibit "biological activity" due to synergistic effects. In this review, we briefly describe the synthesis methods and stability strategies of BP/polymer and BPAs/polymer. Then, advances pertaining to their exciting therapeutic applications in various fields are systematically introduced, such as cancer therapy (phototherapy, drug delivery, and synergistic immunotherapy), bone regeneration, and neurogenesis. Some challenges for future clinical trials and possible directions for further study are finally discussed.

Background Fragility fracture is associated with bone mineral density (BMD), and most databases used in related researches are instrument-matched. Little is known about the relationship between BMD and fragility fracture risk of native Chinese, especially using local databases as reference databases. Objective To investigate relationship between BMD and risk of fragility fracture in native China. Methods 3,324 cases, including 2,423 women (67.7 ± 8.9 years) and 901 men (68.4 ± 11.6 years) having radiological fragility fractures and 3,324 age- and gender-matched controls participated in the study. We measured BMD at posteroanterior spine and hip using dual-energy X-ray absorptiometry (DXA), calculated BMD measurement parameters based on our own BMD reference database. Results BMDs and mean T-scores were lower in case group (with clinical fragility) than in control group (without clinical fragility). In patients with fragility fractures, prevalence of lumbar osteoporosis, low bone mass, and normal BMD were 78.9 %, 19.3 %, and 1.8 %, respectively, in women, and 49.5, 44.8 %, and 5.7 %, respectively, in men. In hip, these prevalence rates were 67.2 %, 28.4 %, and 4.4 % in females, and 43.2 %, 45.9 %, and 10.9 % in males, respectively, showing differences between females and males. Multivariate Cox regression analysis showed that after adjusting age, height, weight, and body mass index, fracture hazard ratio (HR) increased by 2.7–2.8 times (95 % CI 2.5–3.1) and 3.6–4.1 times (95 %CI 3.0–5.1) for women and men respectively with decreasing BMD parameters. In both sexes, risk of fragility fracture increased approximately 1.6–1.7 times (95 % CI 1.5–1.8) for every 1 T-score reduction in BMD. Conclusions Risk of clinical fragility fracture increases with decreasing BMD measurement parameters and anthropometric indicators in native China, and fracture HR varies from gender and site.

Objective To bridge the efficacy and compare the safety of the 24-week teriparatide treatment in a Chinese osteoporosis study ({"type":"clinical-trial","attrs":{"text":"NCT00414973","term_id":"NCT00414973"}}NCT00414973) to a large international trial (FPT, {"type":"clinical-trial","attrs":{"text":"NCT00670501","term_id":"NCT00670501"}}NCT00670501) to determine whether long-term results from the international study were applicable to Chinese patients.

Summary Introduction Vitamin D supplementation has been widely recommended to prevent falls. However, considerable controversy exists regarding the association of such supplementation and fall risk. Previous meta-analyses yielded inconsistent results because of differences in the baseline of 25-hydroxyvitamin D [25(OH)D] and dose of vitamin D and use of vitamin D or in combination with calcium in different studies. Furthermore, some studies published recently were not included in the previous meta-analyses. Therefore, an updated and comprehensive meta-analysis is warranted. Methods We systematically searched several literature databases including PubMed and the Embase from inception to September 2020. The protocol for this meta-analysis was registered with PROSPERO (CRD42021226380). Randomized clinical trials (RCTs) reporting the effect of vitamin D supplementation alone or with calcium on fall incidence were selected from studies. Qualitative and quantitative information was extracted; the random-effects model was conducted to pool the data for fall; statistical heterogeneity was assessed using the I2 test and potential for publication bias was assessed qualitatively by a visual estimate of the funnel plot and quantitatively by calculation of the Begg's test and the Egger's test. Results Of the citations retrieved, 31 eligible studies involving 57 867 participants met inclusion criteria, reporting 17 623 falls. A total of 21 RCTs of vitamin D alone and 10 RCTs of vitamin D plus calcium were included in the meta-analysis. The meta-analysis of 21 RCTs (51 984 participants) of vitamin D supplementation alone (daily or intermittent doses of 400–60 000 IU) did not show a reduced risk of falls (The risk ratio [RR] 1.00, 95% confidence intervals [CI] 0.95 to 1.05) compared to placebo or no treatment. Subgroup analyses showed that the baseline of serum 25(OH)D concentration less than 50 nmol/L resulted in a reduction of fall risk (RR 0.77, 95% CI 0.61 to 0.98). In contrast, the meta-analysis of 10 RCTs (5883 participants) of combined supplementation of vitamin D (daily doses of 700–1000 IU) and calcium (daily doses of 1000–1200 mg) showed a 12% reduction in the risk of fall (RR 0.88, 95% CI 0.80 to 0.97). Conclusions The combination of vitamin D and calcium have beneficial effects on prevention falls in old adults. Although vitamin D supplementation alone has no effect on fall risk in old adults with 25(OH)D levels higher than 50 nmol/L, vitamin D supplementation alone does have a benefit on prevention of falls in old adults with 25(OH)D levels lower than 50 nmol/L.

The aim was to compare the National Osteoporosis Foundation (NOF) and the UK National Osteoporosis Guideline Group (NOGG) guidelines for the detection of vertebral fractures in postmenopausal Chinese women. The NOF guidelines had higher accuracy than the UK guidelines for spinal radiography examination. To compare the National Osteoporosis Foundation (NOF) and the UK National Osteoporosis Guideline Group (NOGG) guidelines for the detection of vertebral fractures in postmenopausal Chinese women. A cross-sectional study on 255 community-dwelling postmenopausal women was conducted in Hunan province in 2017. Demographic and clinical characteristics and risk factors were recorded through questionnaires. Height and weight were measured using standard methods, and bone mineral density (BMD) was measured with dual-energy X-ray absorptiometry. Vertebral fractures were diagnosed by radiography using semi-quantitative morphometry. The prevalence of vertebral fractures was 9.4%. Women with vertebral fractures were significantly older and shorter, had higher years-since menopause and height loss values and lower BMD and T-scores at the femoral neck and total hip, and were more likely to have a history of previous fractures. The sensitivity and specificity of the NOF guidelines were 91.7% and 39.8%, respectively, while the NOGG guidelines had lower sensitivity (87.5%) and specificity (32.5%). However, a higher percentage had indications for radiography in the 50-64 years age group according to the NOGG guidelines, while a higher percentage had indications for radiography in the ≥ 65 year group according to the NOF guidelines. The NOF guidelines were better than the NOGG guidelines for spinal radiography examination in the Chinese postmenopausal women.

The present study demonstrated that the lower-extremity muscle performance in Chinese community-dwelling postmenopausal women with lower bone mineral density (BMD) was positively associated with hip BMD and negatively associated with estimated fracture risk. Postmenopausal women are at high risk for osteoporotic fractures. It has been shown that decreased lower-extremity muscle performance is associated with osteoporotic fractures. However, the relationship between muscle performance and bone mineral density in postmenopausal women is inconsistent in the literature. The present study was to investigate the relationship between lower-extremity muscle performance and BMD or estimated fracture risk in community-dwelling postmenopausal women. Two hundred forty-seven postmenopausal women aged 50–85 years were recruited in the study. The short physical performance battery (SPPB) tool including the chair stand test (CST), gait speed test (GST), and balance test (BT) was used to determine lower-extremity functioning and the CST, GST, BT, and SPPB total scores were recorded. The BMD of lumbar spine (LSBMD), femoral neck (FNBMD), and total hip (THBMD) were measured by dual-energy X-ray absorptiometry (DXA), and the vertebral fracture was confirmed by lateral spine X-rays radiographs. In addition, patients’ 10-year estimated major osteoporotic fracture risk (MOFR) and hip fracture risk (HFR) were assessed by the Fracture Risk Assessment Tool (FRAX). Linear regression analysis was used to analyze the association between muscle performance and BMD. The CST, GST, and SPPB total scores were positively associated with LSBMD, THBMD, and FNBMD before adjustment for age, height, and weight. The SPPB total score was positively associated with FNBMD and THBMD, but not with LSBMD after adjustment for age, height, and weight. The BT score was positively associated with FNBMD and THBMD, but not with LSBMD before and after adjustment for age, height, and weight. Moreover, the CST, GST, BT, and SPPB scores were negatively associated with the FRAX score. The lower-extremity muscle performance in community-dwelling postmenopausal women is positively associated with FNBMD and THBMD and negatively associated with the FRAX score.

The diagnosis and management of osteoporosis and osteoporotic fractures are challenging in rural and underdeveloped areas of China because medical resources are inaccessible; thus, a simple and accurate method is essential for the detection of vertebral fractures. We aimed to examine the relationship between historical height loss (HHL) and vertebral fractures in postmenopausal Chinese women.A cross-sectional study of 255 postmenopausal women aged 50 years or older was conducted in September 2017. Demographic data, including self-reported tallest historical height and current height were analyzed. Vertebral fractures were assessed using X-ray radiography and HHL thresholds were examined using specificity and sensitivity testing.The average age of the 255 participants was 66.3 ± 9.0 years and their mean HHL was 3.5 ± 2.8 cm. The 24 women who were found to have vertebral fractures were older, had more years since menopause (YSM), and a larger HHL compared to those without vertebral fractures. Logistic regression analysis showed that age was a better predictor of vertebral fractures than HHL was, and the cutoff age for detecting vertebral fractures was 71 years, with an area under the receiver operating characteristic curve of 0.750.Although the women in this study with vertebral fractures had a greater height loss than those without fractures, it was apparent that age, rather than HHL, is the best way to determine who is most likely to develop vertebral fractures.

Here, we describe a combination strategy of black phosphorus (BP)-based photothermal therapy together with anti-CD47 antibody (aCD47)-based immunotherapy to synergistically enhance cancer treatment. Tumour resistance to immune checkpoint blockades in most cancers due to immune escape from host surveillance, along with the initiation of metastasis through immunosuppressive cells in the tumour microenvironment, remains a significant challenge for cancer immunotherapy. aCD47, an agent for CD47/SIRPα axis blockade, induces modest phagocytic activity and a low response rate for monotherapy, resulting in failures in clinical trials. We showed that BP-mediated ablation of tumours through photothermal effects could serve as an effective strategy for specific immunological stimulation, improving the inherently poor immunogenicity of tumours, which is particularly useful for enhancing cancer immunotherapy. BP in combination with aCD47 blockade activates both innate and adaptive immunities and promotes local and systemic anticancer immune responses, thus offering a synergistically enhanced effect in suppression of tumour progression and in inducing abscopal effects for inhibition of metastatic cancers. Our combination strategy provides a promising platform in which photothermal agents could help to enhance the therapeutic efficacy of immunotherapy., Immunotherapy: enhancing the therapeutic effectiveness of photothermal cancer treatments By combining photothermal therapy and immunotherapy, scientists have improved cancer treatments. In cancer immunotherapy, the body’s immune system is artificially boosted to fight cancer. Some cancers, however, can protect themselves from immunotherapies by stimulating immune checkpoint targets, which regulate the immune system and prevent it from attacking non-cancerous cells. Checkpoint blockade immunotherapy helps the immune system to recognise and attack cancer cells. However, it is ineffective in treating patients suffering from most solid tumour cancers like melanomas. Now, a team of scientists, led by Paras Prasad from the State University of New York, have used a combination of black phosphorus-based photothermal therapy and antibody immunotherapy to enhance the therapeutic efficiency of the treatment. By exerting a synergistically enhanced antitumor effect, the technique has proved effective in suppressing the proliferation and growth of cancer cells.

Optical techniques using developed laser and optical devices have made a profound impact on modern medicine, with "biomedical optics" becoming an emerging field. Sophisticated technologies have been developed in cancer nanomedicine, such as photothermal therapy and photodynamic therapy, among others. However, single-mode phototherapy cannot completely treat persistent tumors, with the challenges of relapse or metastasis remaining; therefore, combinatorial strategies are being developed. In this review, the role of light in cancer therapy and the challenges of phototherapy are discussed. The development of combinatorial strategies with other therapeutic methods, including chemotherapy, immunotherapy, gene therapy, and radiotherapy, is presented and future directions are further discussed. This review aims to highlight the significance of light in cancer therapy and discuss the combinatorial strategies that show promise in addressing the challenges of phototherapy.

Parathyroid glands contain the vitamin D receptor (VDR) and 25-hydroxyvitamin D-1α-hydroxylase (CYP27B1) and 24-hydroxylase (CYP24A1), which catalyze the production and degradation of 1,25-dihydroxyvitamin D [1,25(OH)2D], respectively. Previous studies have shown that the serum level of intact parathyroid hormone (iPTH) increases with age. We hypothesized that the expression of CYP27B1 or VDR in parathyroid glands decreases with age, which might account for the increased serum levels of iPTH due to decreased suppression of parathyroid hormone (PTH) secretion by 1,25(OH)2D in older people. To test this hypothesis, we examined relative expression levels of VDR, CYP27B1, CYP24A1, and PTH in specimens from parathyroid glands unintentionally removed during thyroidectomy for 70 patients varying in age from 10 to 70 years. The results showed that there was an inverse correlation between age and VDR, CYP27B1, and CYP24A1 expression (p<0.05). A significant positive correlation between PTH expression levels and age was also observed (p<0.05). These data indicate that older age is associated with decreased levels of VDR, CYP27B1, and CYP24A1 and increased levels of PTH in human parathyroid glands.

Ovarian cysts are one of the most common gynecologic affections for females. The most effective therapy is surgery, but not for all conditions. An 18-year-old woman was referred to our hospital because of menstruation disorder and abdominal distension. Ultrasound and computer tomography of the abdomen revealed a giant ovarian cyst. Magnetic resonance imaging revealed profound pituitary enlargement. Laboratory studies showed severe hypothyroidism, mild anemia, hyperlipidemia, hyperprolactinemia and an elevated level of cancer antigen-125. Regression of the giant ovarian cyst and pituitary enlargement was observed after a 5-month levothyroxine replacement therapy. Thus, for patients with ovarian cysts, hypothyroidism should be taken into account. Making correct diagnosis would avoid unnecessary surgery.

Due to their prominent physicochemical properties, 2D materials are broadly applied in biomedicine. Currently, 2D materials have achieved great success in treating many diseases such as cancer and tissue engineering as well as bone therapy. Based on their different characteristics, 2D materials could function in various ways in different bone diseases. Herein, the application of 2D materials in bone tissue engineering, joint lubrication, infection of orthopedic implants, bone tumors, and osteoarthritis are firstly reviewed comprehensively together. Meanwhile, different mechanisms by which 2D materials function in each disease reviewed below are also reviewed in detail, which in turn reveals the versatile functions and application of 2D materials. At last, the outlook on how to further broaden applications of 2D materials in bone therapies based on their excellent properties is also discussed.

Two-dimensional (2D) monoelemental bismuth (Bi) crystal, one of the pnictogens (group VA), has recently attracted increasing interest because of its intriguing characteristics. Here, uniformly sized 2D Bi quantum dots (BiQDs) with an average diameter (thickness) of 4.9 ± 1.0 nm (2.6 ± 0.7 nm) were fabricated through a facile liquid-phase exfoliation (LPE) method, and the corresponding photoresponse was evaluated using photoelectrochemical (PEC) measurements. The as-fabricated BiQDs-based photodetector not only exhibits an appropriate capacity for self-driven broadband photoresponse but also shows high-performance photoresponse under low bias potentials ranging from UV to visible light in association with long-term stability of the ON/OFF switching behavior. In terms of these findings, it is further anticipated that the resultant BiQDs possess promising potential in UV–visible photodetection as well as in liquid optoelectronics. Our work may open a new avenue for delivering high-quality monoelemental pnict...

Importance The aging of the population is associated with an increasing burden of fractures worldwide. However, the epidemiological features of fractures in mainland China are not well known. Objective To assess the prevalence of and factors associated with osteoporosis, clinical fractures, and vertebral fractures in an adult population 40 years or older in mainland China. Design, setting. and participants This cross-sectional study, the China Osteoporosis Prevalence Study, was conducted from December 2017 to August 2018. A random sample of individuals aged 20 years or older who represented urban and rural areas of China were enrolled, with a 99% participation rate. Main outcomes and measures Weighted prevalence of osteoporosis, clinical fracture, and vertebral fracture by age, sex, and urban vs rural residence as determined by x-ray absorptiometry, questionnaire, and radiography. Results A total of 20 416 participants were included in this study; 20 164 (98.8%; 11 443 women [56.7%]; mean [SD] age, 53 [13] years) had a qualified x-ray absorptiometry image and completed the questionnaire, and 8423 of 8800 (95.7%) had a qualified spine radiograph. The prevalence of osteoporosis among those aged 40 years or older was 5.0% (95% CI, 4.2%-5.8%) among men and 20.6% (95% CI, 19.3%-22.0%) among women. The prevalence of vertebral fracture was 10.5% (95% CI, 9.0%-12.0%) among men and 9.7% (95% CI, 8.2%-11.1%) among women. The prevalence of clinical fracture in the past 5 years was 4.1% (95% CI, 3.3%-4.9%) among men and 4.2% (95% CI, 3.6%-4.7%) among women. Among men and women, 0.3% (95% CI, 0.0%-0.7%) and 1.4% (95% CI, 0.8%-2.0%), respectively, with osteoporosis diagnosed on the basis of bone mineral density or with fracture were receiving antiosteoporosis treatment to prevent fracture. Conclusions and relevance In this cross-sectional study of an adult population in mainland China, the prevalence of osteoporosis and vertebral fracture were high and the prevalence of vertebral fracture and clinical fracture was similarly high in men and women. These findings suggest that current guidelines for screening and treatment of fractures among patients in China should focus equally on men and women and should emphasize the prevention of vertebral fractures.

Purpose: We aimed to investigate the status of serum 25-hydroxyvitamin D [25(OH)D] among Chinese postmenopausal women in a multicenter cross-sectional study.Methods: Non-institutionalized postmenopausal women aged ≥55 years were recruited from urban and rural areas in 7 geographically different regions in China. Subject enrollment was executed during the summer and the winter. Vitamin D insufficiency and deficiency were defined as 25(OH)D < 30 and< 20 ng/ml, and was measured by liquid chromatography-tandem mass spectrometry. Women were referred to a dual-energy x-ray absorptiometry (DXA) if they had a medium-to-high fracture risk suggested by Osteoporosis Self-Assessment Tool for Asians (OSTA).Results: Among all subjects, 91.2% (1,535/1,684, 95%CI: 89.7, 92.5) had vitamin D insufficiency and 61.3% had vitamin D deficiency (1,033/1,684, 95%CI: 59.0, 63.7). The prevalence of vitamin D deficiency was significantly higher in urban dwellers (64.9 vs. 57.7% in rural, P = 0.002) and in winter-enrolled subjects (84.7 vs. 41.3% in summer, P < 0.0001). The prevalence of vitamin D inadequacy did not increase in trend by latitude and was numerically lower in women who had high fracture risk and osteoporosis. A non-curvilinear change of intact parathyroid hormone (iPTH) levels was observed at 25(OH)D >16.78 ng/mL.Conclusions: The prevalence of vitamin D inadequacy was remarkable among Chinese postmenopausal women and independent of fracture risk assessed by OSTA or osteoporosis suggested by DXA. Winter season, urban residence, however not latitude, were significantly associated with a higher likelihood of vitamin D deficiency. Optimal vitamin D status for iPTH and bone-related outcomes merits further investigation in this population.

Therapeutic targeting of the immune system, including chimeric antigen receptor-T cell therapy, immune checkpoint blockade therapy, neoantigen vaccines, and small molecule modulators emerges as one of the most effective therapeutic modalities for treating various cancers in human patients. However, clinical efficacies of these immunotherapeutics are generally modest and only a minority of cancer patients benefit from immunotherapy. Further, broad adverse effects, lack of reliable biomarkers, tumour relapses, drug resistance, and metastasis have become increasingly recognized concerns, which may restrain their clinical utility. Unlike most other anticancer strategies, nanomaterial-based therapeutics parade unique and distinct biological features to achieve precision targeting, local drug release, and enhancing therapeutic efficacy. As long-term and sustained release of immunotherapeutics are necessary for enhancing anticancer immunity, nanotechnology ensures accumulation of immunotherapuetics, controlled release, and precision delivery of immune drugs. Combination of these two therapeutic modalities would provide synergistic efficacy for effectively treating various cancers in human patients. To the best of our knowledge, the concept of combination therapy employing nanomaterials and immunotherapy has been overlooked. In this article, we discuss possible mechanisms underlying nano-immunotherapy and unique opportunities of nanotechnology in synergizing cancer treatment.

Photodynamic therapy (PDT), as a non-invasive therapeutic modality that is alternative to radiotherapy and chemotherapy, is extensively investigated for cancer treatments. Although conventional organic photosensitizers (PSs) are still widely used and have achieved great progresses in PDT, the disadvantages such as hydrophobicity, poor stability within PDT environment and low cell/tissue specificity largely limit their clinical applications. Consequently, nano-agents with promising physicochemical and optical properties have emerged as an attractive alternative to overcome these drawbacks of traditional PSs. Herein, the up-to-date advances in the fabrication and fascinating applications of various nanomaterials in PDT have been summarized, including various types of nanoparticles, carbon-based nanomaterials, and two-dimensional nanomaterials, etc. In addition, the current challenges for the clinical use of PDT, and the corresponding strategies to address these issues, as well as future perspectives on further improvement of PDT have also been discussed.

Water shortage is one of the most concerning global challenges in the 21st century. Solar‐inspired vaporization employing photothermal nanomaterials is considered to be a feasible and green technology for addressing the water challenge by virtue of abundant and clean solar energy. 2D nanomaterials aroused considerable attention in photothermal evaporation‐induced water production owing to their large absorption surface, strong absorption in broadband solar spectrum, and efficient photothermal conversion. Herein, the recent progress of 2D nanomaterials‐based photothermal evaporation, mainly including emerging Xenes (phosphorene, antimonene, tellurene, and borophene) and binary‐enes (MXenes and transition metal dichalcogenides), is reviewed. Then, the optimization strategies for higher evaporation performance are summarized in terms of modulation of the intrinsic photothermal performance of 2D nanomaterials and design of the complete evaporation system. Finally, the challenges and prospective of various kinds of 2D photothermal nanomaterials are discussed in terms of the photothermal performance, stability, environmental influence, and cost. One important principle is that solutions for water challenges should not introduce new environmental and social problems. This Review aims to highlight the role of 2D photothermal nanomaterials in solving water challenges and provides a viable scheme toward the practical use in photothermal materials selection, design, and evaporation systems building., The recent progress of two‐dimensional (2D) nanomaterials‐based photothermal evaporation owing to the unique advantages of 2D photothermal nanomaterials, such as the large absorption surface, strong absorption in broadband solar spectrum, and efficient photothermal conversion is reviewed. This Review aims to highlight the role of 2D photothermal nanomaterials in solving the water challenges through employing the abundant and clean solar energy.

cited By 2; International audience; In the framework of solid-state cooling technologies, four kinds of caloric effects, i.e., magnetocaloric (MC), electrocaloric (EC), barocaloric (BC) and elastocaloric (eC) effects, have been compared from the viewpoint of environmental issues and application cases. This field is primarily developed with the intention of protecting the environment. Currently, alternative caloric materials (called “good” materials) with properties such as being environmentally friendly, low-cost and practicable (low stimulus field) need to be found. All current caloric effects/materials are investigated for the common objective of cooling. Due to the variety of stimuli and intrinsic properties (different caloric performances for different dimensions) of caloric materials, they can exhibit unique advantages for various application cases. A “good” caloric material for large-scale cooling application is still rare and requires more research. © 2016 Elsevier Ltd

Black phosphorus (BP), a typical mono-elemental and two-dimensional (2D) material, has gathered significant attention owing to its distinct optoelectronic properties and promising applications, despite its main obstacle of long-term stability. Consequently, BP-analog materials with long-term chemical stability show additional potential. In this contribution, tin sulfide (SnS), a novel two-elemental and 2D structural BP-analog monochalcogenide, has been demonstrated to show enhanced stability under ambient conditions. The broadband nonlinear optical properties and carrier dynamics have been systematically investigated via Z-scan and transient absorption approaches. The excellent nonlinear absorption coefficient of 50.5×10−3 cm/GW, 1 order of magnitude larger than that of BP, endows the promising application of SnS in ultrafast laser generation. Two different decay times of τ1∼873 fs and τ2∼96.9 ps allow the alteration between pure Q switching and continuous-wave (CW) mode locking in an identical laser resonator. Both mode-locked and Q-switched operations have been experimentally demonstrated using an SnS saturable absorber at the telecommunication window. Femtosecond laser pulses with tunable wavelength and high stability are easily obtained, suggesting the promising potential of SnS as an efficient optical modulator for ultrafast photonics. This primary investigation may be considered an important step towards stable and high-performance BP-analog material-based photonic devices.

Two-dimensional (2D) materials exhibit many interesting properties, but most 2D materials are exfoliated from layered bulk materials, limiting the development of the 2D material group. Recently, non-layered 2D materials have aroused great attention due to their excellent catalysis performance, favored compatibility with silicon substrates and high chemical activity. With high photoconductivity, high responsivity and fast response time, non-layered selenium (Se) exhibits important applications in the field of optoelectronics. In this work, we use a simple liquid phase exfoliation method to fabricate 2D Se nanoflakes from bulk Se which possesses a unique chain structure. The thickness of 2D Se nanoflakes was measured to be in the range of 5-10 nm. As-fabricated Se nanoflakes were used in a photodetector by the photoelectrochemical method, showing a high photocurrent density (1.28 μA cm-2) and photoresponsivity (10.45 μA W-1). In addition, the long-term photoelectric measurements indicate that the 2D Se-based photodetector has good time and cycle stability. Our results show that 2D Se has promising potential in liquid-based photo-detectors.

Investigations into 2D nanomaterials are of considerable significance from both an academic and industrial point of view. The present work addresses, for the first time, the fabrication of 2D nonlayered ultrathin selenium through a facile liquid-phase exfoliation method. The results reveal that the as-prepared 2D Se nanosheets are 40–120 nm in lateral dimension and 3–6 nm in thickness. The nanosheets exhibit a trigonal crystalline phase similar to their bulk counterpart, indicating the conservation of the crystalline features during the exfoliation procedure. The successful preparation of 2D Se nanosheets from nonlayered bulk Se can be ascribed to two kinds of anisotropy: (1) that of crystalline bulk Se with chain-like structures, where strong intrachain SeSe covalent bonds coexist with weak interchain van der Waals forces, and (2) that of probe sonication in the vertical direction. The results also show that the 2D Se nanosheets possess a size-dependent band gap (E g), strong photoluminescence effect and robust, chemical stability under ambient conditions. Furthermore, a 2D Se-nanosheet-based optical modulation device is demonstrated that allows for excellent ultrashort pulse generation of an optical communication band. It is therefore anticipated that 2D Se nanosheets may find significant applications in both photoluminescence and ultrafast photonics.

Vitamin D deficiency is reportedly linked to a variety of autoimmune diseases. However, the relationship between thyroid autoimmunity in Graves disease (GD) and vitamin D deficiency is unclear. The goal of this study was to determine whether increased thyroid hormone autoantibody titer is associated with vitamin D deficiency in GD patients.A total of 70 patients with GD and 70 matched control subjects were recruited to our study. The levels of 25-hydroxyvitamin D (25[OH]D), calcium, parathyroid hormone (PTH), free triiodothyronine (FT3), free thyroxine (FT4), thyroid-stimulating hormone (TSH), thyrotropin-receptor antibody (TRAb), thyroid-peroxidase antibody (TPOAb), and thyroglobulin antibody (TGAb) in serum collected from these patients and controls were examined.The level of 25(OH)D in serum from TRAb-positive GD patients was significantly lower than that in serum of healthy controls or TRAb-negative patients. However, compared with control subjects, the level of PTH in serum was increased in TRAb-positive GD patients. The rate of vitamin D deficiency (defined as serum 25[OH]D50 nmol/L) in TRAb-positive GD patients was significantly higher than in healthy controls or TRAb-negative GD patients. The level of 25(OH)D in serum was inversely correlated with TRAb titer in serum of TRAb-positive GD patients. However, our results did not show a correlation between 25(OH)D level and the levels of TPOAb, TGAb, FT3, FT4, or TSH.Low vitamin D status is associated with increased TRAb titer in GD, suggesting a possible link between vitamin D status and increased thyroid autoimmunity in GD patients.

OBJECTIVES Recent studies suggest that serum lipid profiles are related to bone mineral density (BMD). But data about this relationship on Chinese population are scarce. We investigated the relationships between serum lipid and BMD in postmenopausal Chinese women. METHODS A cross-sectional study was conducted in 790 Chinese postmenopausal women. BMDs were measured by dual X-ray absorptiometry. Serum lipid profiles were obtained after a 12-h fasting. RESULTS Women with serum high-density lipoprotein cholesterol (HDL-C) levels of at least 1·55 mmol/l had a greater prevalence of osteoporosis compared with women with lower HDL-C (≤1·54 mmol/l). After controlling for age, menopausal duration, body mass index, serum creatinine levels, outdoor activity, smoking and alcohol intake, high HDL-C levels were associated with osteoporosis (OR = 1·64, 95%CI 1·16-2·33, P < 0·01). BMD at femoral neck and total hip was significantly lower in the higher HDL-C class than the lower class (0·722 ± 0·118 vs 0·744 ± 0·120 g/cm(2) , P < 0·01; 0·800 ± 0·126 vs 0·824 ± 0·125 g/cm(2) , P < 0·01, respectively). No association was found between total cholesterol (TC), triglyceride (TG) and low-density lipoprotein cholesterol (LDL-C) with BMD. CONCLUSIONS In Chinese postmenopausal women, elevated levels of serum HDL-C had a greater probability of being osteoporosis than the lower HDL-C levels. Our analysis showed higher HDL-C level that is favourable for cardiovascular diseases should be regarded as a risk factor for osteoporosis.

Over the past few decades, there has been a growing interest in understanding the multifunctional characteristics and clinical importance of vitamin D binding protein (DBP). Multiple studies have shed light on DBP, giving rise to hopes of identifying novel mechanisms as well as utilizing DBP as a potential therapeutic agent. The current issue is comprised of 6 manuscripts, two of which are review articles. The areas covered in this special issue mostly highlight the potential role of DBP in several conditions including periodontitis and frailty, implying that measurement of DBP may provide useful information in addition to total 25-hydroxy vitamin D concentration. In this issue, the review by P. Yousefzadeh et al. titled “Vitamin D binding protein impact on 25-hydroxyvitamin D levels under different physiologic and pathologic conditions” calls for the implementation of DBP testing during the interpretation of 25-hydroxyvitamin D [25(OH)D] results under different clinical situations. I. Bhan reviews the recent findings regarding the association between the differences in vitamin D binding protein levels and bone density in his paper titled “Vitamin D binding protein and bone health.” The author has compiled studies concerned with DBP, including DBP polymorphisms in relation to bone health and its association with vitamin D bioavailability. These findings may impact not only strategies for designing novel therapeutic agents that influence DBP or its binding, but also our understanding of the mechanism of vitamin D in the context of bone health. Evidence is emerging that the DBP polymorphisms are associated with race and ethnicity, resulting in differences in DBP levels and binding affinity that affect the transport and metabolism of vitamin D and its metabolites. Using serum samples from various populations with varying DBP levels, J. Freeman et al., in their paper titled “Influence of vitamin D binding protein on accuracy of 25-hydroxyvitamin D measurement using the ADVIA Centaur vitamin D total assay,” assessed the agreement between the ADVIA Centaur vitamin D total assay for 25(OH)D testing and the liquid chromatography mass spectrometry (LS-MS/MS) method and concluded that the ADVIA Centaur vitamin D total assay demonstrated good performance compared to the LS-MS/MS method across the normal range of DBP concentrations. This is one example of methods development in the field to ensure accurate and simpler protocols for measuring circulating 25(OH)D in future study. X. Zhang et al., in their paper titled “Vitamin D-binding protein levels in plasma and gingival crevicular fluid (GCF) of patients with generalized aggressive periodontitis,” examined the association of DBP with generalized aggressive periodontitis (GAgP). The authors found that GAgP patients had higher plasma DBP concentrations but lower GCF DBP concentrations than healthy controls, suggesting that decreased GCF-DBP level and increased plasma DBP level are associated with periodontitis. This study adds to the growing evidence of the potential role of DBP in the pathogenesis of periodontitis. Existing evidence shows an association of high circulating 25(OH)D levels with low TSH levels in younger individuals, but there is insufficient information on whether it is the same in the elderly and middle-aged. Q. Zhang et al., in their paper titled “Association of high vitamin D status with low circulating thyroid-stimulating hormone independent of thyroid hormone levels in middle-aged and elderly males,” report that such an association does exist in middle-aged and elderly males, independent of thyroid hormone levels. The authors also demonstrated the link between vitamin D insufficiency and serum thyroid antibody levels. Y. Wang et al., in their paper entitled “Vitamin D binding protein affects the correlation of 25(OH)D and frailty in the older men,” assessed the frailty status in elderly men of Changsha city, China, and concluded that serum DBP levels should be measured when evaluating the 25(OH)D- frailty relationship. We hope that these articles convey new insights to readers and researchers into the current renewed interest in vitamin D and DBP research. Zhongjian Xie Arthur C. Santora Sue A. Shapses Xiangbing Wang