Disaggregated Nano-Hydroxyapatite (DnHAP) with Inhibitory Effects on Biofilms and Demineralization

Nano-hydroxyapatite (nHAP) is considered a biocompatible agent that promotes the remineralization of dental hard tissue; however, its antibacterial efficacy is under scientific discussion. Therefore, this investigation aimed to specify the inhibitory effects of disaggregated nano-hydroxyapatite (DnHAP) on regrown biofilms and demineralization. Regrown biofilm models of single-species (Streptococcus mutans), dual-species (S. mutans and Candida albicans), and saliva-derived microcosm biofilms were established in vitro. Repeat treatment with DnHAP was applied to biofilms. The viability, lactic acid, biofilm structure, biomass, the inhibitory effect of demineralization, and virulence factors' expression were determined. In addition, the biofilm microbial community was analyzed by 16S ribosomal RNA gene sequencing. DnHAP inhibited metabolism, lactic acid production, biomass, and water-insoluble polysaccharide production (P < 0.05) of regrown single/dual-species biofilms. Concerning the saliva-derived biofilms, samples treated with DnHAP showed lower biofilm metabolic activity without significant differences from samples treated with sterile deionized water (P > 0.05); in addition, saliva-derived biofilms treated with DnHAP exhibited lower lactic acid production (P < 0.05). The demineralization of bovine enamel was the lowest in the DnHAP group, as detected by transverse microradiography, and the lesion depth and volume decreased significantly (P < 0.05). The application of DnHAP did not change the diversity of regrown saliva-derived microcosm biofilms. In conclusion, this investigation showed that DnHAP could be a promising solution for the management of regrown biofilms to combat dental caries.

[Clinical features and prognosis of 118 children with histiocytic necrotizing lymphadenitis]

Objective: To explore the clinical features and prognosis of children with histiocytic necrotizing lymphadenitis (HNL). Methods: The clinical data of 118 children with HNL diagnosed and treated in the Department of Rheumatology and Immunology of Children's Hospital, Capital Institute of Pediatrics from January 2014 to December 2021 were retrospectively analyzed. The clinical symptoms, laboratory examination, imaging examination, pathological findings, treatment and follow-up were analyzed. Results: Among the 118 patients, 69 were males and 49 were females. The age of onset was 10.0 (8.0, 12.0) years, ranging from 1.5 to 16.0 years. All the children had fever lymph node enlargement, blood system involvement in 74 cases (62.7%), skin injury in 39 cases (33.1%). The main manifestations of laboratory examination were increased erythrocyte sedimentation rate in 90 cases (76.3%), decreased hemoglobin in 58 cases (49.2%), decreased white blood cells in 54 cases (45.8%) and positive antinuclear antibody in 35 cases (29.7%). Ninety-seven cases (82.2%) underwent B-mode ultrasound of lymph nodes, showing nodular lesions with low echo in the neck; 22 cases (18.6%) underwent cervical X-ray and (or) CT; 7 cases (5.9%) underwent cervical magnetic resonance imaging. Lymph node biopsy was performed in all 118 cases, and the pathological results did not support malignant diseases such as lymphoma or Epstein-Barr virus infection, suggesting HNL. Fifty-seven cases (48.3%) recovered without treatment, 61 cases (51.7%) received oral steroid therapy, and 4 cases (3.4%) received indomethacin as anal stopper. The 118 cases were followed up for 4 (2, 6) years, ranging from 1 to 7 years, 87 cases (73.7%) had one onset and did not develop into other rheumatological diseases, and 24 cases (20.3%) had different degrees of recurrence, 7 cases (5.9%) had multiple system injuries, and all of the tested autoantibodies were positive for medium and high titers. All of them developed into other rheumatic immune diseases, among which 5 cases developed into systemic lupus erythematosus and 2 cases developed into Sjogren's syndrome; 7 cases were given oral steroid therapy, including 6 cases plus immunosuppressant and 2 cases receiving methylprednisolone 20 mg/kg shock therapy. Conclusions: The first-onset HNL portion is self-healing, hormone-sensitive and has a good prognosis. For HNL with repeated disease and multiple system injury, antinuclear antibody titer should be monitored during follow-up, and attention should be paid to the possibility of developing into other rheumatological diseases, with poor prognosis.

Modeling directed weighted network based on event coincidence analysis and its application on spatial propagation characteristics

The problem of synchronicity quantification, based on event occurrence time, has become the research focus in different fields. Methods of synchrony measurement provide an effective way to explore spatial propagation characteristics of extreme events. Using the synchrony measurement method of event coincidence analysis, we construct a directed weighted network and innovatively explore the direction of correlations between event sequences. Based on trigger event coincidence, the synchrony of traffic extreme events of base stations is measured. Analyzing topology characteristics of the network, we study the spatial propagation characteristics of traffic extreme events in the communication system, including the propagation area, propagation influence, and spatial aggregation. This study provides a framework of network modeling to quantify the propagation characteristics of extreme events, which is helpful for further research on the prediction of extreme events. In particular, our framework is effective for events that occurred in time aggregation. In addition, from the perspective of a directed network, we analyze differences between the precursor event coincidence and the trigger event coincidence and the impact of event aggregation on the synchrony measurement methods. The precursor event coincidence and the trigger event coincidence are consistent when identifying event synchronization, while there are differences when measuring the event synchronization extent. Our study can provide a reference for the analysis of extreme climatic events such as rainstorms, droughts, and others in the climate field.

Properties of Cosmic-Ray Sulfur and Determination of the Composition of Primary Cosmic-Ray Carbon, Neon, Magnesium, and Sulfur: Ten-Year Results from the Alpha Magnetic Spectrometer

We report the properties of primary cosmic-ray sulfur (S) in the rigidity range 2.15 GV to 3.0 TV based on 0.38×10^{6} sulfur nuclei collected by the Alpha Magnetic Spectrometer experiment (AMS). We observed that above 90 GV the rigidity dependence of the S flux is identical to the rigidity dependence of Ne-Mg-Si fluxes, which is different from the rigidity dependence of the He-C-O-Fe fluxes. We found that, similar to N, Na, and Al cosmic rays, over the entire rigidity range, the traditional primary cosmic rays S, Ne, Mg, and C all have sizeable secondary components, and the S, Ne, and Mg fluxes are well described by the weighted sum of the primary silicon flux and the secondary fluorine flux, and the C flux is well described by the weighted sum of the primary oxygen flux and the secondary boron flux. The primary and secondary contributions of the traditional primary cosmic-ray fluxes of C, Ne, Mg, and S (even Z elements) are distinctly different from the primary and secondary contributions of the N, Na, and Al (odd Z elements) fluxes. The abundance ratio at the source for S/Si is 0.167±0.006, for Ne/Si is 0.833±0.025, for Mg/Si is 0.994±0.029, and for C/O is 0.836±0.025. These values are determined independent of cosmic-ray propagation.

[EHHADH is a key gene in fatty acid metabolism pathways in hepatocellular carcinoma: a transcriptomic analysis]

OBJECTIVE

To explore the driving gene of hepatocellular carcinoma (HCC) occurrence and progression and its potential as new therapeutic target of HCC.

METHODS

The transcriptome and genomic data of 858 HCC tissues and 493 adjacent tissues were obtained from TCGA, GEO, and ICGC databases. Gene Set Enrichment Analysis (GSEA) identified EHHADH (encoding enoyl-CoA hydratase/L-3-hydroxyacyl-CoA dehydrogenase) as the hub gene in the significantly enriched differential pathways in HCC. The downregulation of EHHADH expression at the transcriptome level was found to correlate with TP53 mutation based on analysis of the TCGA- HCC dataset, and the mechanism by which TP53 mutation caused EHHADH downregulation was explored through correlation analysis. Analysis of the data from the Metascape database suggested that EHHADH was strongly correlated with the ferroptosis signaling pathway in HCC progression, and to verify this result, immunohistochemical staining was used to examine EHHADH expression in 30 HCC tissues and paired adjacent tissues.

RESULTS

All the 3 HCC datasets showed signficnatly lowered EHHADH expression in HCC tissues as compared with the adjacent tissues (P < 0.05) with a close correlation with the degree of hepatocyte de-differentiation (P < 0.01). The somatic landscape of HCC cohort in TCGA dataset showed that HCC patients had the highest genomic TP53 mutation rate. The transcriptomic level of PPARGC1A, the upstream gene of EHHADH, was significantly downregulated in HCC patients with TP53 mutation as compared with those without the mutation (P < 0.05), and was significantly correlated with EHHADH expression level. GO and KEGG enrichment analyses showed that EHHADH expression was significantly correlated with abnormal fatty acid metabolism in HCC. The immunohistochemical results showd that the expression level of EHHADH in HCC tissues was down-regulated, and its expression level was related to the degree of hepatocytes de-differentiation and the process of ferroptosis.

CONCLUSION

TP53 mutations may induce abnormal expression of PPARGC1A to cause downregulation of EHHADH expression in HCC. The low expression of EHHADH is closely associated with aggravation of de-differentiation and ferroptosis escape in HCC tissues, suggesting the potential of EHHADH as a therapeutic target for HCC.

A quinary WTaCrVHf nanocrystalline refractory high-entropy alloy withholding extreme irradiation environments

In the quest of new materials that can withstand severe irradiation and mechanical extremes for advanced applications (e.g. fission & fusion reactors, space applications, etc.), design, prediction and control of advanced materials beyond current material designs become paramount. Here, through a combined experimental and simulation methodology, we design a nanocrystalline refractory high entropy alloy (RHEA) system. Compositions assessed under extreme environments and in situ electron-microscopy reveal both high thermal stability and radiation resistance. We observe grain refinement under heavy ion irradiation and resistance to dual-beam irradiation and helium implantation in the form of low defect generation and evolution, as well as no detectable grain growth. The experimental and modeling results-showing a good agreement-can be applied to design and rapidly assess other alloys subjected to extreme environmental conditions.

2,3,4',5-Tetrahydroxystilbene-2-O-β-d-glucoside attenuates atherosclerotic progression by inhibiting inflammation via downregulation of TNF receptor-associated factor 6 expression

OBJECTIVE

Atherosclerosis (As) is an inflammatory disease, and 2,3,4',5-tetrahydroxystilbene-2-O-β-d-glucoside (TSG) has been shown to suppress inflammation. However, it is still unclear if TSG alleviates As by inhibiting inflammation.

MATERIALS AND METHODS

Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to assess the mRNA levels of tumor necrosis factor (TNF) receptor-associated factor 6 (TRAF6), TNF-α and interleukin-6 (IL-6) in lipoprotein E knockout (ApoE -/-) mice with As. Hematoxylin-eosin (H&E) staining was performed to examine the atherosclerotic plaques in the aortic sinus. QRT-PCR and western blotting were used to measure the expression levels of TRAF6, TNF-α, and IL-6 in human umbilical vein endothelial cells (HUVECs), and enzyme-linked immunosorbent assays (ELISAs) were performed to monitor the levels of TNF-α and IL-6 in serum and cell culture medium.

RESULTS

TSG inhibited subendothelial plaques formation in the aortic sinus and inhibited the levels of total cholesterol (TCHO), low-density lipoprotein (LDL), TRAF6, TNF-α and IL-6 in AS mice in a dose-dependent manner. Moreover, TSG attenuated the oxidatively modified LDL (ox-LDL)-induced increases in TRAF6, TNF-α and IL-6 expression, whereas TRAF6 overexpression reversed the TSG-induced decreases in TRAF6, TNF-α, and IL-6 expression in HUVECs.

CONCLUSIONS

TSG attenuates atherosclerotic progression by inhibiting inflammation via the downregulation of TRAF6 in ApoE-/- mice and HUVECs.

Spatial-temporal variation of the carbon sequestration rate of afforestation in China: Implications for carbon trade and planning

Afforestation and reforestation (A&R) are nature-based and cost-effective solutions for enhancing terrestrial carbon sinks and facilitating faster carbon neutrality. However, the lack of hierarchical spatial-temporal maps for the carbon sequestration rate (CSR) from A&R at the national scale impedes the scientific implementation of forest management planning to a large extent. Here, we assessed the spatial-temporal CSR per area for A&R at the provincial, prefectural, and county levels in China using a forest carbon sequestration model under three climate scenarios. Results showed that the CSR of vegetation (CSR_Veg), soil (CSR_Soil), and the ecosystem (CSR_Eco) significantly varied across space and time. In China, the CSR_Veg, CSR_Soil, and CSR_Eco were primarily regulated by the spatial variations in temperature and precipitation. Additionally, CSR_Veg was found to be positively influenced by precipitation and temperature, whereas temperature had a negative influence on CSR_Soil. Therefore, the differences between the CSR_Veg and CSR_Soil should be emphasized in the future. These information on the spatiotemporal variation of CSR of A&R (vegetation, soil, and ecosystem) on unit area basis and at levels of province, prefecture, and county in China, can be used as a comparable protocol to estimate the carbon sinks of A&R at different scales. Overall, these hierarchical spatiotemporal maps for CSR on A&R may help to identify priority areas of forest management planning and carbon trade policy to achieve faster carbon neutrality for China in the future.

Temporal Structures in Electron Spectra and Charge Sign Effects in Galactic Cosmic Rays

We present the precision measurements of 11 years of daily cosmic electron fluxes in the rigidity interval from 1.00 to 41.9 GV based on 2.0×10^{8} electrons collected with the Alpha Magnetic Spectrometer (AMS) aboard the International Space Station. The electron fluxes exhibit variations on multiple timescales. Recurrent electron flux variations with periods of 27 days, 13.5 days, and 9 days are observed. We find that the electron fluxes show distinctly different time variations from the proton fluxes. Remarkably, a hysteresis between the electron flux and the proton flux is observed with a significance of greater than 6σ at rigidities below 8.5 GV. Furthermore, significant structures in the electron-proton hysteresis are observed corresponding to sharp structures in both fluxes. This continuous daily electron data provide unique input to the understanding of the charge sign dependence of cosmic rays over an 11-year solar cycle.

[Comparative analysis of clinical diagnosis and treatment guidelines for drug-induced liver injury at home and abroad]

Drug-induced liver injury influencing factors are complex and have diverse clinical manifestations. Simple and reliable diagnostic methods are still deficient, and further classification of toxicological mechanisms is required. There are numerous pertinent discrepancies between domestic and international guidelines aimed at drug-induced liver injury diagnosis and treatment, with partial to no consensus on the content. The American Gastroenterological Association's 2021 Clinical Guidelines, the Asia-Pacific Association for the Study of the Liver's 2021 Consensus Guidelines, the Council for International Organizations of Medical Sciences' 2020 International Consensus, the European Society's Hepatology Committee's 2019 Clinical Practice Guidelines, and the 2015 Chinese Medical Association Guidelines are five influential clinical guidelines on drug-induced liver injury at home and abroad. The epidemiology, risk factors, diagnosis and evaluation, treatment management, and other contents, particularly traditional Chinese medicine, were compared and analyzed using other relevant consensus opinions or guidelines in order to improve understanding and provide a reference for clinical diagnosis and treatment of drug-induced liver injury.

The global prevalence of premature ovarian insufficiency: a systematic review and meta-analysis

OBJECTIVE

The objective of this review was to answer the global prevalence of premature ovarian insufficiency (POI), and explore the associated factors including etiopathology and regions with POI.

METHODS

The search was conducted on reports from a total of eight databases that comprised Chinese National Knowledge Infrastructure (CNKI), Wanfang, China BioMedical Literature Database (CBM), PubMed, the Cochrane Library, Embase, Web of Science and Ovid MEDLINE^® between 1946 and 2021. To analyze the source of heterogeneity, we performed subgroup analysis based on different etiologies and regions. Meta-analysis was carried out by Stata14.0 software.

RESULTS

The results showed that the global overall prevalence of POI among women was 3.5%. By subgroup analysis, the prevalence of POI among women with iatrogenic etiology was 11.2%, followed by autoimmunity (10.5%); the prevalence of POI by region was 11.3% at the highest in North America followed by South America (5.4%); and the prevalence of POI was 5.3% in a developing country, higher than 3.1% in a developed country. The trend of prevalence of POI over the past 20 years was on the rise (although p > 0.05).

CONCLUSION

We recommend that health and medical institutions strengthen public health awareness, achieve health-education goals related to POI and increase women's awareness of and attention to POI.

Functions and interaction of plant lipid signalling under abiotic stresses

Lipids are the primary form of energy storage and a major component of plasma membranes, which form the interface between the cell and the extracellular environment. Several lipids - including phosphoinositide, phosphatidic acid, sphingolipids, lysophospholipids, oxylipins, and free fatty acids - also serve as substrates for the generation of signalling molecules. Abiotic stresses, such as drought and temperature stress, are known to affect plant growth. In addition, abiotic stresses can activate certain lipid-dependent signalling pathways that control the expression of stress-responsive genes and contribute to plant stress adaptation. Many studies have focused either on the enzymatic production and metabolism of lipids, or on the mechanisms of abiotic stress response. However, there is little information regarding the roles of plant lipids in plant responses to abiotic stress. In this review, we describe the metabolism of plant lipids and discuss their involvement in plant responses to abiotic stress. As such, this review provides crucial background for further research on the interactions between plant lipids and abiotic stress.

[The mechanism, inducement and long-term effects of acquired weakness in intensive care units]

With the development of critical care medicine, the case fatality rate in intensive care units (ICU) patients has decreased significantly, but most patients still suffer from the long-term problems of related complications after discharge, which seriously affects the quality of life and social integration after discharge. Complications such as ICU acquired weakness (ICU-AW) and Post-ICU Syndrome (PICS) are not uncommon throughout the treatment of severe patients. The treatment of critically ill patients should not only focus on the treatment of the disease, but also gradually extend to the whole-process physiological-psychological-social medical intervention mode in the ICU, during the stay in the general ward and after discharge. On the basis of ensuring patient safety, patients' physical and psychological status assessment in the early stage of ICU admission, and disease prevention as soon as possible, which can reduce the long-term impact on the quality of life and social work after discharge.

Drug monitoring detects under- and overdosing in patients receiving 5-fluorouracil-containing chemotherapy-results of a prospective, multicenter German observational study

INTRODUCTION

Body surface area (BSA)-based dosing of 5-fluorouracil (5-FU) results in marked inter-individual variability in drug levels, whereas determination of plasma 5-FU concentration and area under the curve (AUC) is a more precise dosing method but has not been integrated into clinical routine. We conducted a multicenter, prospective study to study 5-FU AUC distributions and assess clinical factors predicting therapeutic dosing in patients receiving BSA-dosed 5-FU.

METHODS

Between June 2017 and January 2018, a total of 434 patients receiving continuous, infusional BSA-dosed 5-FU from 37 sites in Germany were included. Plasma 5-FU concentration and AUC were measured in venous blood samples at steady state. The primary objective was to determine 5-FU AUC distributions in relation to the target range, which is defined as 20-30 mg × h/l. The second objective was to explore clinical parameters that correlate with achievement of 5-FU AUC target range.

RESULTS

The primary tumor was mainly located in the gastrointestinal tract (96.3%), with colorectal cancer being the most common (71.2%) tumor entity. 5-FU was administered as monotherapy (8.1%) or as part of FOLFOX (33.2%), FOLFIRI (26.3%), or other regimens (12.4%). Treatment setting was adjuvant (31.3%) or metastatic (64.5%). The median AUC was 16 mg × h/l. Only 20.3% of patients received 5-FU treatment within the target range, whereas the majority of patients (60.6%) were underdosed and 19.1% of patients were overdosed. In the univariate logistic regression, treatment setting was the only clinical parameter that significantly correlated with achievement of the target range. Patients treated in the metastatic setting had a 2.1 (95% confidence interval 1.186-3.776, P = 0.011) higher odds to reach the target range compared with patients treated in the adjuvant setting.

CONCLUSIONS

The majority of patients received suboptimal doses of 5-FU using BSA dosing. Therapeutic drug monitoring of 5-FU is an option for optimized individualized cancer therapy and should be integrated into the clinical practice.

A stochastic animal life cycle simulation model for a whole dairy farm system model: Assessing the value of combined heifer and lactating dairy cow reproductive management programs

This analysis introduces a stochastic herd simulation model and evaluates the estimated reproductive and economic performance of combinations of reproductive management programs for both heifers and lactating cows. The model simulates the growth, reproductive performance, production, and culling for individual animals and integrates individual animal outcomes to represent herd dynamics daily. The model has an extensible structure, allowing for future modification and expansion, and has been integrated into the Ruminant Farm Systems model, a holistic dairy farm simulation model. The herd simulation model was used to compare outcomes of 10 reproductive management scenarios based on common practices on US farms with combinations of estrous detection (ED) and artificial insemination (AI), synchronized estrous detection (synch-ED) and AI, timed AI (TAI, 5-d CIDR-Synch) programs for heifers; and ED, a combination of ED and TAI (ED-TAI, Presynch-Ovsynch), and TAI (Double-Ovsynch) with or without ED during the reinsemination period for lactating cows. The simulation was run for a 1,000-cow (milking and dry) herd for 7 yr, and we used the outcomes from the final year to evaluate results. The model accounted for incomes from milk, sold calves, and culled heifers and cows, as well as costs from breeding, AI, semen, pregnancy diagnosis, and calf, heifer, and cow feed. We found that the interaction between heifer and lactating dairy cow reproductive management programs influences herd economic performance primarily due to heifer rearing costs and replacement heifer supply. The greatest net return (NR) was achieved when combining heifer TAI and cow TAI without ED during the reinsemination period, whereas the lowest NR was obtained when combining heifer synch-ED with cow ED.

Predicting inhabitable areas for locust based on field observation and multi-environmental factors in alpine grassland—A case study in the Qilian Mountain National Park, China

Alpine grassland is one of the most critical grassland types in the world, and it is vulnerable and sensitive to external disturbances. The development and outbreak of locust might result in the irreversible degradation. However, most locust studies have been on the tropical, temperate, and desert areas. Our knowledge of inhabitable areas in alpine grassland still needs to be explored. This study was carried out in the alpine grassland in the Qilian Mountain National Park. Environmental factors (remote sensing vegetation index, meteorology, soil, topography, and grassland types) and their impact on locust density were investigated. Finally, the inhabitable areas of locust in the study area were mapped. The results showed that: (1) six out of 26 factors [including precipitation, solar radiation (average and maximum value), normalized vegetation index (NDVI), soil, and temperature] had great influence on locust density, with a relative contribution (RC) more than 10%. (2) Among all locust density estimation models, those based on average and maximum solar radiation, maximum precipitation, maximum NDVI, average temperature, and clay content in deep soil performed better than others, with R ranging from 0.58 to 0.73 and root mean square error ranging from 21.70 to 25.82 head/m2. (3) The areas most suited for locust growth, development, and frequent outbreak were found in the south of Tianjun County, middle and northwest of Qilian County (account for 27% of the study area), while the inhabitability was weak in south of Gangcha County, northwest of Tianjun County, and most of Delingha City. Thus our study clarified the distribution region and occurrence variation of the locust and provided a scientific basis for locust prevention and control in alpine grassland in the Qilian Mountain National Park.

YKL-40 as a novel biomarker related to white matter damage and cognitive impairment in patients with cerebral small vessel disease

YKL-40 is a novel neuroinflammatory marker associated with white matter damage and cognitive dysfunction. 110 CSVD patients, including 54 with mild cognitive impairment (CSVD-MCI), 56 with no cognitive impairment (CSVD-NCI), and 40 healthy controls (HCs) underwent multimodal magnetic resonance examination, serum YKL-40 level detection and cognitive function assessment to investigate the association between YKL-40 and white matter damage and cognitive impairment in cerebral small vessel disease (CSVD) patients. White matter hyperintensities volume was calculated using the Wisconsin White Matter Hyperintensity Segmentation Toolbox (W2MHS) for white matter macrostructural damage evaluation. For white matter microstructural damage evaluation, fractional anisotropy (FA) and mean diffusivity (MD) indices of the region of interest were analyzed based on diffusion tensor imaging (DTI) images using the Tract-Based Spatial Statistics (TBSS) pipeline. The serum YKL-40 level of CSVD was significantly higher than those of HCs, and the CSVD-MCI was higher than in HCs and CSVD-NCI. Furthermore, serum YKL-40 provided high diagnostic accuracy for CSVD and CSVD-MCI. The macroscopic and microstructure of white matter in CSVD-NCI and CSVD-MCI patients indicated different degrees of damage. Disruption of white matter macroscopic and microstructure was significantly associated with YKL-40 levels and cognition deficits. Moreover, the white matter damage mediated the associations between the increased serum YKL-40 levels and cognitive impairment. Our findings demonstrated that YKL-40 might be a potential biomarker of white matter damage in CSVD, whereas white matter damage was associated with cognitive impairment. Serum YKL-40 measurement provides complementary information regarding the neural mechanism of CSVD and its associated cognitive impairment.

High prevalence of vertebral deformity in tumor-induced osteomalacia associated with impaired bone microstructure

PURPOSE

Patients with tumor-induced osteomalacia (TIO) often suffer from irreversible height loss due to vertebral deformity. However, the prevalence of vertebral deformity in TIO patients varies among limited studies. In addition, the distribution and type of vertebral deformity, as well as its risk factors, remain unknown. This study aimed to identify the prevalence, distribution, type and risk factors for vertebral deformity in a large cohort of TIO patients.

METHODS

A total of 164 TIO patients were enrolled in this retrospective study. Deformity in vertebrae T4-L4 by lateral thoracolumbar spine radiographs was evaluated according to the semiquantitative method of Genant. Bone microstructure was evaluated by trabecular bone score (TBS) and high-resolution peripheral QCT (HR-pQCT).

RESULTS

Ninety-nine (99/164, 60.4%) patients had 517 deformed vertebrae with a bimodal pattern of distribution (T7-9 and T11-L1), and biconcave deformity was the most common type (267/517, 51.6%). Compared with patients without vertebral deformity, those with vertebral deformity had a higher male/female ratio, longer disease duration, more height loss, lower serum phosphate, higher bone turnover markers, lower TBS, lower areal bone mineral density (aBMD), lower peripheral volumetric BMD (vBMD) and worse microstructure. Lower trabecular vBMD and worse trabecular microstructure in the peripheral bone and lower spine TBS were associated with an increased risk of vertebral deformity independently of aBMD. After adjusting for the number of deformed vertebrae, we found little difference in clinical indexes among the patients with different types of vertebral deformity. However, we found significant correlations of clinical indexes with the number of deformed vertebrae and the spinal deformity index.

CONCLUSION

We reported a high prevalence of vertebral deformity in the largest cohort of TIO patients and described the vertebral deformity in detail for the first time. Risk factors for vertebral deformity included male sex, long disease duration, height loss, abnormal biochemical indexes and bone impairment. Clinical manifestation, biochemical indexes and bone impairment were correlated with the number of deformed vertebrae and degree of deformity, but not the type of deformity.