Occurrence of microplastics in the headwaters of Yellow River on the Tibetan Plateau: Source analysis and ecological risk assessment.

The widespread occurrence of Microplastics (MPs) has aroused increasing concerns. However, the fate of MPs in remote areas remains poorly understood. Here, the spatial distribution, potential sources, and environmental risks of MPs were analyzed in the headstream of the Yellow River on the eastern Tibetan Plateau. The average MP abundances are (464.3 ± 200.9) items /m3 and (63.6 ± 34.7) items /kg in the water and sediment, respectively, with both majority polymer is polypropylene (PP) (water: 28.7 %; sediment: 25.2 %). The structural equation modeling and conditional fragmentation model were used in this study to analyze the source and impact factors of riverine MPs. According to the models, MPs were influenced by water quality parameters and anthropogenic activities. Furthermore, the source analysis through MP characteristics and statistical analysis showed that the main sources of MPs include domestic sewage, plastic waste disposal, and the use of agricultural plastic film. Moreover, the differences in MP sources along the river were distinguished by the conditional fragmentation model. The potential ecological risks of MPs were evaluated, resulting in relatively medium-to-low levels. Our findings will serve as important references for improving the understanding of the plateau environmental impacts of MP distribution in the headwaters of large rivers.

Dissolved trace elements in the upper reaches of Lancang River, southeast Qinghai-Tibet Plateau: Current status and distribution, risk and source.

The environmental impact of dissolved trace element (DTE) pollution is becoming increasingly well understood. The southeastern edge of the Qinghai-Tibet Plateau is a region with high environmental vulnerability, making it highly susceptible to various anthropogenic disturbances. The Lancang River (LCR), as the most representative river in this area, serving as the largest international river in Southeast Asia, the LCR is crucial for the downstream regions, supporting fisheries, agriculture, and even economic development, earning it the title of the "water tower" for these areas. This study mainly focuses on the upstream unbuilt dam area. In this study, we gathered 25 surface water samples from the upstream of the LCR and examined the geographical distribution, primary sources, and associated human health risks of seven dissolved trace elements (Mn, Cr, Fe, Co, Cu, Ni, Zn). Cr, Fe, Co, Ni, and Cu in the main stream are primarily associated with natural sources, including rock weathering, soil erosion, and similar processes. Mn, however, predominantly originates from human activities such as industrial construction and road transportation. Zn mainly originates from the specialized fertilizers used for highland barley in plateau regions. Almost all DTE concentrations exhibited a downward trend from upstream to downstream. However, due to inputs from various sources along the way, there will be some abnormal points. The concentrations of DTE in the study area were within the acceptable limits set by drinking water standards in China, the USA, and the WHO. Overall, the water quality in this region is considered good. The results from a Monte Carlo simulation assessing health risks indicate that the non-carcinogenic health risk caused by DTE in the upper reaches of Lancang River was very weak. The primary pathway through which DTE can harm human health is ingestion, with children being particularly vulnerable. These findings offer a critical scientific basis for understanding the migration of DTE in aquatic environments and for the ecological stewardship of the Lancang River.

Tibetan lake change linked to large-scale atmospheric oscillations via hydroclimatic trajectory.

Lakes are known as sentinels of climate change, but their responses may differ from one to another leading to different strategies in lake protection. It is particularly the case in the Tibetan Plateau (TP) of multiple hydrological processes. We employed the Budyko framework to study Tibetan lakes from two lake-basins of contrasting climates for the period between 1980 and 2022: Taro Co Basin (TCB) in a sub-arid climate, and Ranwu Lake Basin (RLB) in a sub-humid climate. Our results showed that total lake area, surface air temperature, evapotranspiration, and potential evapotranspiration increased in both lake-basins, while precipitation and soil moisture increased in the TCB but decreased in the RLB. In the Budyko space, two basins had contrast hydroclimatic trajectories in terms of aridity and evaporative index. The TCB shifted from wetting to drying trend, while the RLB from drying to wetting in early 2000s. Notably, lake change was generally consistent with the drying/wetting phases in the TCB, but in contrast with that in the RLB, which can be attributed to warming-induced glacier melting. Despite of significant correlation with the large-scale atmospheric oscillations, it turned to be more plausible if lake area changes were substituted with basin's hydroclimatic trajectories. Among the large-scale oscillations, El Niño-Southern Oscillation (ENSO) is the most dominant control of lake trends and their drying/wetting shifts. Our findings offer a valuable insight into lake responses to climate change in the TP and other regions.

Prevalence and genotype distribution of human papillomavirus infection among 66000 women from 2014 to 2023 in the plateau region of Southwest China.

BACKGROUND: Persistent infection with high-risk human papillomavirus (HR-HPV) plays a key role in the onset of cervical cancer. This study was designed to examine the epidemiological trends and genotype distribution of HPV from 2014 to 2023 in the plateau region of Southwest China. METHODS: The findings could offer valuable insights for clinical screening of cervical cancer and the formulation of HPV vaccination policies. This retrospective study analyzed 66,000 women who received HPV-DNA testing at the First People's Hospital of Qujing, Yunnan, China, between 2014 and 2023. The cohort consisted of 33,512 outpatients, 3,816 inpatients, and 28,672 individuals undergoing health examinations. Cervical cells were collected for DNA extraction, and PCR amplification along with Luminex xMAP technology were used to detect 27 HPV genotypes. The data analysis was conducted using GraphPad Prism and IBM SPSS Statistics 27 software. RESULTS: The overall HPV infection rate at the First People's Hospital of Qujing declined from 24.92% in 2014 to 16.29% in 2023, averaging 16.02%. Specific infection rates were 18.50% among outpatients, 12.97% among inpatients, and 13.53% for health examination attendees. The predominant high-risk HPV genotypes identified were HPV52 (2.61%), HPV16 (2.06%), HPV58 (1.81%), HPV53 (1.55%), and HPV39 (1.09%). Meanwhile, the most frequent low-risk HPV genotypes were HPV6 (1.30%), HPV61 (1.21%), and HPV11 (0.85%). In HPV-positive cases, the distribution of single, double, triple, and quadruple or more infections were 79.90%, 15.17%, 3.59%, and 1.33%, respectively. The proportions of pure LR-HPV, pure HR-HPV, and mixed infections were 22.16%, 67.82%, and 10.02%, respectively. Age-specific analysis revealed a bimodal distribution of HPV infection, with the infection rate rapidly decreasing from 44.02% in the ≤ 19 age group to 19.55% in the 20-29 age group and 13.84% in the 30-39 age group, followed by a gradual increase to 14.64% in the 40-49 age group, 16.65% in the 50-59 age group, and 22.98% in the ≥ 60 age group. The coverage rates of the three available vaccines are all below 50%. The results of this study indicated a declining trend in HPV prevalence in the plateau region of Southwest China over the period from 2014 to 2023, especially in the reduction of genotypes targeted by vaccines. CONCLUSION: There were significant variations in the genotypes prevalent among different age groups, years, and patient sources within the same region. The underwhelming vaccination rates emphasize the critical need for developing either a multivalent vaccine or a personalized vaccine that targets the HPV genotypes common in the Chinese population. Furthermore, vaccinating adolescents to curb HPV infection and ensuring regular cervical cancer screenings for postmenopausal women are crucial steps.

The meniscotibial ligament does exist: An anatomic and histological description.

Purpose: To describe the anatomical and histological characteristics of the human MTL (meniscotibial ligament) that keeps the meniscus stable and are rarely discussed. Study design: Descriptive laboratory study. Methods: In total, six fresh-frozen adult cadaver knees were dissected, and the dissection protocol were designed by two experienced anatomy professors. The anatomical morphology of MTL was observed. The main anatomical specimens included meniscus, tibial plateau, MTL. The osteotome was used to excise the portion of the tibial plateau, which could obtain the complex including partial meniscus, MTL, and a tibial fragment. A histopathologic study was performed by two experienced pathologists. Results: Macroscopically, the MTL could be divided into two parts: medial meniscotibial ligament (MMTL)and lateral meniscotibial ligament (LMTL). The MMTL is distributed continuously, whereas the LMTL is discontinuous on the tibial plateau. The average length from the tibial attachment of the LMTL to the articular surface was 19 ± 1.0mm (mean ± SD). The average length from the tibial attachment of the MMTL to the articular surface was 10 ± 1.2 mm (mean ± SD). Microscopy of the MTL showed that the MTL is a ligamentous tissue, composed of a network of oriented collagenous fibers. Conclusions: In all knees, the MTL was inserted on the outer edge of the meniscus, attaching to the tibia below the level of articular cartilage, which was key to maintaining the rotational stability of knee and the meniscus in the physiological position on the tibial plateau. Histological analysis of this ligament demonstrated that the MTL is a veritable ligamentous structure, which is made up of collagen type I-expressing fibroblasts. Clinical relevance: This article contributes to the understanding of the anatomical and histological characteristics of the MTL. It is beneficial to promote the development of relevant surgical techniques for the MTL lesion.

Dynamic brain functional states associated with inhibition control under different altitudes.

Chronic exposure to the hypobaric hypoxia environment of plateau could influence human cognitive behaviours which are supported by dynamic brain connectivity states. Until now, how functional connectivity (FC) of the brain network changes with altitudes is still unclear. In this article, we used EEG data of the Go/NoGo paradigm from Weinan (347 m) and Nyingchi (2950 m). A combination of dynamic FC (dFC) and the K-means cluster was employed to extract dynamic FC states which were later distinguished by graph metrics. Besides, temporal properties of networks such as fractional windows (FW), transition numbers (TN) and mean dwell time (MDT) were calculated. Finally, we successfully extracted two different states from dFC matrices where State 1 was verified to have higher functional integration and segregation. The dFC states dynamically switched during the Go/NoGo tasks and the FW of State 1 showed a rise in the high-altitude participants. Also, in the regional analysis, we found higher state deviation in the fronto-parietal cortices and enhanced FC strength in the occipital lobe. These results demonstrated that long-term exposure to the high-altitude environment could lead brain networks to reorganize as networks with higher inter- and intra-networks information transfer efficiency, which could be attributed to a compensatory mechanism to the compromised brain function due to the plateau environment. This study provides a new perspective in considering how the plateau impacted cognitive impairment.

A clinical evaluation of variation in paediatric intracranial pressure waveforms.

Introduction: Intracranial pressure (ICP) monitoring is commonly used in investigating the aetiology of chronic paediatric neurological conditions. A series of high-amplitude spikes has been observed in overnight ICP recordings of some children, many of whom have hydrocephalus or craniosynostosis. Research question: This clinical evaluation aimed to define the spike pattern, describe the patient group in which it is most likely to occur, and conduct high-resolution waveform analysis. Material and methods: ICP waveforms from 40 patients aged 0-5 years (inclusive), recorded between 2017 and 2021 at the Royal Hospital for Children Glasgow, were retrospectively analysed. The pattern was defined through visual inspection of regions of interest by two reviewers. Patients were stratified using demographic and clinical data. R software was used to perform regression and high-resolution waveform analyses. Results: The spike pattern was defined as the presence of 2 consecutive spikes with an amplitude of at least 8 mmHg, with a gap of at least 30 min between spikes. In the adjusted Poisson regression, age was significantly associated with the number of spikes (IRR 0.8, 95% CI 0.70 to 0.92, p-value 0.001). Discussion and conclusion: Younger age was significantly associated with an increased number of spikes in this cohort. Investigation of clinical consequences of the spikes is warranted.

Total knee arthroplasty following surgical treatment of tibial plateau fractures - A retrospective cohort study.

BACKGROUND: Previous studies have shown the risk of post-traumatic osteoarthritis to be high following tibial plateau fracture surgery. Several investigations have examined the risk of total knee arthroplasty (TKA) following tibial plateau fracture treatment, but the risk of TKA in relation to the general population in Sweden has not previously been explored. AIM: To determine the incidence of TKA following surgical treatment of tibial plateau fractures and compare it with that of an age-matched population in Sweden. METHODS: A total of 349 tibial plateau fractures treated with open reduction internal fixation between 2002 and 2010 were identified from local hospital registers using diagnosis and surgical codes. The cohort was cross-matched with the Swedish Knee Arthroplasty Register to determine which patients had been treated with TKA within 10 years of fracture surgery. The incidence of primary TKA in the age-matched population in Sweden was obtained from the National Patient Register for comparison. RESULTS: Mortality-adjusted prevalence of TKA at 10 years following fracture surgery was 6.7% (relative risk (RR) = 5.5) and peaked during the second postoperative year (RR=19.3). High age was independently associated with increased risk of TKA (P=0.004); no other examined patient factors were significantly associated with TKA. CONCLUSION: The overall prevalence of TKA at 10 years following tibial plateau fracture surgery is low at 6.7%, however the risk is many times greater than that of the age-matched population in Sweden. The majority of patients require TKA within a few years of fracture treatment, hence post-traumatic osteoarthritis may arguably have not been the reason for TKA as this would have taken longer to develop.

The microbial community structure and nitrogen cycle of high-altitude pristine saline lakes on the Qinghai-Tibetan plateau.

The nitrogen (N) cycle is the foundation of the biogeochemistry on Earth and plays a crucial role in global climate stability. It is one of the most important nutrient cycles in high-altitude lakes. The biogeochemistry of nitrogen is almost entirely dependent on redox reactions mediated by microorganisms. However, the nitrogen cycling of microbial communities in the high-altitude saline lakes of the Qinghai-Tibet Plateau (QTP), the world's "third pole" has not been investigated extensively. In this study, we used a metagenomic approach to investigate the microbial communities in four high-altitude pristine saline lakes in the Altun mountain on the QTP. We observed that Proteobacteria, Bacteroidota, and Actinobacteriota were dominant in these lakes. We reconstructed 1,593 bacterial MAGs and 8 archaeal MAGs, 1,060 of which were found to contain nitrogen cycle related genes. Our analysis revealed that nitrite reduction, nitrogen fixation, and assimilatory nitrate reduction processes might be active in the lakes. Denitrification might be a major mechanism driving the potential nitrogen loss, while nitrification might be inactive. A wide variety of microorganisms in the lake, dominated by Proteobacteria, participate together in the nitrogen cycle. The prevalence of the dominant taxon Yoonia in these lakes may be attributed to its well-established nitrogen functions and the coupled proton dynamics. This study is the first to systematically investigate the structure and nitrogen function of the microbial community in the high-altitude pristine saline lakes in the Altun mountain on the QTP. As such, it contributes to a better comprehension of biogeochemistry of high-altitude saline lakes.

Tibiofemoral axial rotation in tibial plateau fractures: A retrospective radiographic assessment of 203 tibial plateau fractures.

BACKGROUND: Defining the injury-force mechanism in tibial plateau fractures (TPFs) could help define implant type and position, as well as soft tissues at risk. The aim of this study was to provide an analysis of injury-force-mechanisms in TPFs, including axial rotation. METHODS: The injury-force mechanism was determined for 203 fractures that presented over a period of 3.5 years. Fractures were classified as flexion-varus/valgus/neutral or (hyper)-extension-varus/valgus/neutral by observing articular depression area on CT/MRI. Fractures were subclassified into rotation-neutral, internal- or external-rotation according to the Gerdy-tibial-tuberosity-surgical-epicondylar-axis (GTT-SEA) angle. Soft-tissue injury was documented if MRI was performed. RESULTS: Flexion-valgus was the most common injury-force mechanism (n = 85, 41.9%), followed by extension-valgus (n = 57, 28.1%). Other mechanisms were less common (9.4% extension-varus, 5.9% flexion-neutral, 4.9% flexion-varus, 3.9% hyperextension-valgus, 3.4% extension-neutral and 2.5% hyperextension-varus). The GTT-SEA angle could be measured in 194 (95.6%) of 203 classified patients, revealing internal rotation in 83 (42.8%) and external rotation in 53 (27.3%). No significant difference was found between injury-force mechanism type and axial rotation group (P = 0.964) or extent of rotation (H(8) = 7.116, P = 0.524). Only 41 (21.1%) of 194 fully classified fractures underwent MRI, all revealing soft-tissue injury to some extent. High-grade posterolateral injuries occurred mainly in rotated TPF. CONCLUSION: Our results describe the common forms of axial rotation present in TPF and explore their association with injury-force mechanism and soft-tissue injury. Applying the injury-force mechanism patterns and addressing rotational forces could, together with preoperative MRI and intra-operative stability assessment, help determine the need to surgically address associated soft-tissue injury.

The changing permafrost environment under desertification and the heat transfer mechanism in the Qinghai-Tibetan Plateau.

With the development of desertification in the Qinghai-Tibet Plateau (QTP), aeolian sand becomes the remarkable local factor affecting the thermal state of permafrost along the Qinghai-Tibet Engineering Corridor (QTEC). In this study, a model experiment was conducted to analyze the impact of thickness and water content of aeolian sand on its thermal effect, and a hydro-thermo-vapor coupling model of frozen soil was carried out to reveal the heat transfer mechanism of the aeolian sand layer (ASL) with different thicknesses and its hydrothermal effect on permafrost. The results indicate that: (1) ASL with the thickness larger than 80 cm has the property of converting precipitation into soil water. The thicker the ASL, the more precipitation infiltrates and accumulates in the soil layer. (2) The cooling effect of ASL on permafrost results from the lower net surface radiation, causing the annual average surface heat flux shifting from heat inflow to heat outflow. The warming effect of ASL on permafrost results from the increasing convective heat accompanying the infiltrated precipitation. (3) As the ASL thickens, the thermal effect of ASL on permafrost gradually shifts from the cooling effect dominated by heat radiation and heat conduction to the warming effect dominated by precipitation infiltration and heat convection. The warming effect of thick ASL on permafrost requires a certain amount of years to manifest, and the critical thickness is suggested to be larger than 120 cm.

High biological N fixation potential dominated by heterotrophic diazotrophs in alpine permafrost rivers on the Qinghai‒Tibet Plateau.

Biological nitrogen (N) fixation is a pivotal N source in N-deficient ecosystems. The Qinghai‒Tibet Plateau (QTP) region, which is assumed to be N limited and suboxic, is an ideal habitat for diazotrophs. However, the diazotrophic communities and associated N fixation rates in these high-altitude alpine permafrost QTP rivers remain largely unknown. Herein, we examined diazotrophic communities in the sediment and biofilm of QTP rivers via the nitrogenase (nifH) gene sequencing and assessed their N fixing activities via a 15N isotope incubation assay. Strikingly, anaerobic heterotrophic diazotrophs, such as sulfate- and iron-reducing bacteria, had emerged as dominant N fixers. Remarkably, the nifH gene abundance and N fixation rates increased with altitude, and the average nifH gene abundance (2.57 ± 2.60 × 108 copies g-1) and N fixation rate (2.29 ± 3.36 nmol N g-1d-1) surpassed that documented in most aquatic environments (nifH gene abundance: 1.31 × 105 ∼ 2.57 × 108 copies g-1, nitrogen fixation rates: 2.34 × 10-4 ∼ 4.11 nmol N g-1d-1). Such distinctive heterotrophic diazotrophic communities and high N fixation potential in QTP rivers were associated with low-nitrogen, abundant organic carbon and unique C:N:P stoichiometries. Additionally, the significant presence of psychrophilic bacteria within the diazotrophic communities, along with the enhanced stability and complexity of the diazotrophic networks at higher altitudes, clearly demonstrate the adaptability of diazotrophic communities to extreme cold and high-altitude conditions in QTP rivers. We further determined that altitude, coupled with organic carbon and phosphorus, was the predominant driver shaping diazotrophic communities and their N-fixing activities. Overall, our study reveals high N fixation potential in N-deficient QTP rivers, which provides novel insights into nitrogen dynamics in alpine permafrost rivers.

Effects of the Direction of Two Kirschner Wires on Combined Tibial Plateau Leveling Osteotomy and Tibial Tuberosity Transposition in Miniature Breed Dogs: An Ex Vivo Study.

This study evaluates the impact of Kirschner wire (K-wire) insertion direction on the biomechanical properties of combined tibial plateau leveling osteotomy (TPLO) and tibial tuberosity transposition (TTT) procedures in small-breed dogs with cranial cruciate ligament rupture and medial patella luxation. Twenty-one cadaveric tibiae were divided into two groups; the specimens were divided into two groups; one underwent TPLO-TTT with a proximal pin placement (Group TTP), and the other received TPLO-TTT with a distal pin placement (Group TTD). For both pin placements, two additional subgroups were formed: one with a 0.56 mm tension band (Groups TTP0.56 and TTD0.56) and the other with a 0.76 mm tension band (Groups TTP0.76 and TTD0.76). The tensile force was applied, and failure load and mode were recorded. The distal pin direction in Group TTD0.56 exhibited a significantly higher mean failure load (380.1 N) compared to the proximal pin direction in Group TTP0.56 (302.2 N, p = 0.028). No significant differences were observed among the other groups. This study concludes that distal pin placement can provide similar or improved mechanical stability in cases with limited space for proximal pin placement during combined TPLO and TTT procedures.

Seasonal dynamics of free-living (FL) and particle-attached (PA) bacterial communities in a plateau reservoir.

In terms of lifestyle, bacterioplankton can be classified as free-living (FL) and particle-attached (PA) forms, and both play essential roles in biogeochemical cycling in aquatic ecosystems. Structure, distribution, and community assembly of FL and PA bacteria in plateau riverine waterbodies are largely unknown. Therefore, we explored the seasonal dynamics of FLand PA bacterial communities in the Wujiangdu reservoir, Yungui Plateau using 16S rRNA gene high-throughput sequencing. Results revealed there was a significant environmental heterogeneity in Wujiangdu reservoir seasonally. The dominant phylum was Actinomycetota for FL and Pseudomonadota for PA bacteria. Species richness and diversity was higher in autumn and winter compared to spring and summer. In general, PA diversity was greater than FL, but with some temporal variations. Species turnover was the major contributor to ß-diversity of both FL and PA lifestyles, and significant differences were noticed between FL and PA bacterial community composition. Distinct co-occurrence network patterns implied that more connections exist between FL bacteria, while more complex PA networks were in parallel to their greater diversity and stronger interactions in biofilms on particles. Dispersal limitation was the major driving force for both FL and PA bacterial community assembly. Deterministic processes were of relatively low importance, with homogeneous selection for FL and heterogeneous selection for PA bacteria. Temperature was the most important environmental driver of seasonal bacterial dynamics, followed by nitrate for FL and Secchi depth for PA bacteria. This study allows for a better understanding of the temporal variability of different bacteria lifestyles in reservoirs in the vulnerable and rapidly changing plateau environment, facilitating further microbial research related to global warming and eutrophication.

Maintenance of joint reduction and allograft incorporation in treating tibial plateau fractures. Retrospective case series using cortico-cancellous, non-irradiated, bone allograft.

Background: Restoring joint congruence and maintaining reduction until healing is imperative in treating tibial plateau fractures (TPF). The main objective of this study was to evaluate the feasibility of augmentation with impacted bone allograft (IBA) to prevent loss of reduction in tibial plateau fractures during healing and to evaluate its incorporation. Methods: We retrospectively analyzed all patients with an acute, closed tibial plateau fracture (Schatzker II, III, IV) treated between 2010 and 2019 with open reduction and internal fixation (ORIF) and impacted bone allograft (IBA), with a minimum follow-up of 24 months. We evaluated the postoperative radiographs by drawing a line along the tibial axis and another perpendicular to the healthy plateau to measure the reduction and subsequent behavior. The incorporation of the allograft was evaluated by radiological analysis assessing its integration, non-union, resorption, or sclerosis. We used the clinical-radiological Rasmussen system and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) to objectify the outcomes. Results: 78 TPFs were included, with a median age of 51.5 (40.7-62.2) years and a median follow-up of 66 (24-89) months. Two (2.5 %) patients presented loss of joint reduction (subsidence) during the follow-up regarding the achieved in the surgery. Seventy-six (94.7 %) patients presented integration, two (2.5 %) resorption, and one (1.3 %) sclerosis. Seventy-two (92.3 %) patients presented excellent and good results in the Rasmussen radiological score, and 72 (92.3 %) patients presented excellent or good clinical scores. The mean WOMAC at two years postoperatively was 15 ± 6.5. Conclusion: Our results demonstrate that allograft is an adjuvant in maintaining a reduction in type II, III, and IV Schatzker's tibial plateau fractures. Low rates of loss of reduction during follow-up can be expected with its use.

The Knee injury and Osteoarthritis Outcome Score (KOOS) for lateral tibial plateau fractures- relevance, reliability and responsiveness.

BACKGROUND: This study aimed to evaluate the patient-reported relevance, test-retest reliability, and responsiveness for each of the five KOOS subscales in patients with lateral tibial plateau fractures. METHODS: Adult patients with surgically treated lateral tibial plateau fractures (AO 41B) were included. The primary outcome measure was the KOOS subscales: Pain, Symptoms, Activity of Daily Living (ADL), Sport and Recreational Activities (Sport/rec), and kne-related Quality of Life (QOL). The KOOS was repeated at 14 and 15 days, six weeks, and 6 and 12 months. Content validity was partly evaluated by patients ranking the relevance of all the items in the KOOS, test-retest reliability by an interclass correlation coefficient, and responsiveness by effect size and based on 3 pre-defined hypotheses related the the global rating of change. RESULTS: Forty-one patients with a mean age of 54.8 years (ranging from 21 to 81 years) were included. The results showed an acceptable relevance of all the KOOS subscales. The test-retest reliability was moderate to high for all five subscales, with an interclass-correlation coefficient ranging from 0.6 to 0.9. At the 6- and 12-month follow-ups, the responsiveness showed large effect sizes for all the KOOS subscales, ranging from 0.9 to 2.1. Moderate to high correlations (r ≥ 0.4)was observed for the predefine hypotheses. CONCLUSION: The KOOS questionnaire showed acceptable relevance, high test-retest reliability and acceptable responsivness within one year following a lateral tibial plateau fracture. More research is needed for further validation of psychometric properties of KOOS for patients with lateral tibial plateau fractures.

Central nervous injury risk factors after endovascular repair of a thoracic aortic aneurysm with type B aortic dissection.

BACKGROUND: Aortic dissection is the deadliest disease of the cardiovascular system. Type B aortic dissection accounts for 30%-60% of aortic dissections and is mainly treated by endovascular repair of thoracic endovascular aneurysm repair (TEVAR). However, patients are prone to various complications after surgery, with central nervous system injury being the most common, which seriously affects their prognosis and increases the risk of disability and death. Therefore, exploring the risk factors of central nervous system injury after TEVAR can provide a basis for its prevention and control. AIM: To investigate the risk factors for central nervous system injury after the repair of a thoracic endovascular aneurysm with type B aortic dissection. METHODS: We enrolled 306 patients with type B aortic dissection who underwent TEVAR at our hospital between December 2019 and October 2022. The patients were categorized into injury (n = 159) and non-injury (n = 147) groups based on central nervous system injury following surgery. The risk factors for central nervous system injury after TEVAR for type B aortic dissection were screened by comparing the two groups. Multivariate logistic regression analysis was performed. RESULTS: The Association between age, history of hypertension, blood pH value, surgery, mechanical ventilation, intensive care unit stay, postoperative recovery times on the first day after surgery, and arterial partial pressure of oxygen on the first day after surgery differed substantially (P < 0.05). Multivariate logistic regression analysis indicated that age, surgery time, history of hypertension, duration of mechanical ventilation, and intensive care unit stay were independent risk factors for central nervous system injury after TEVAR of type B aortic dissection (P < 0.05). CONCLUSION: For high-risk patients with central nervous system injury after TEVAR of type B aortic dissection, early intervention measures should be implemented to lower the risk of neurological discomfort following surgery in high-risk patients with central nervous system injury after TEVAR for type B aortic dissection.

3D PRINTING IN COMPLEX TIBIAL FRACTURE CLASSIFICATION & PLANNING.

Objective: Tibial plateau fractures are common intra-articular fractures that pose classification and treatment challenges for orthopedic surgeons. Objective: This study examines the value of 3D printing for classifying and planning surgery for complex tibial plateau fractures. Methods: We reviewed 54 complex tibial plateau fractures treated at our hospital from January 2017 to January 2019. Patients underwent preoperative spiral CT scans, with DICOM data processed using Mimics software. 3D printing technology created accurate 1:1 scale models of the fractures. These models helped subdivide the fractures into seven types based on the tibial plateau's geometric planes. Surgical approaches and simulated operations, including fracture reduction and plate placement, were planned using these models. Results: The 3D models accurately depicted the direction and extent of fracture displacement and plateau collapse. They facilitated the preoperative planning, allowing for precise reconstruction strategies and matching intraoperative details with the pre-printed models. Post-surgery, the anatomical structure of the tibial plateau was significantly improved in all 54 cases. Conclusion: 3D printing effectively aids in the classification and preoperative planning of complex tibial plateau fractures, enhancing surgical outcomes and anatomical restoration. Level of Evidence IV, Prospective Study.

Objetivo: As fraturas do planalto tibial são fraturas intra-articulares comuns de classificação e tratamento desafiadores aos cirurgiões ortopédicos. Objetivo: Este estudo investiga o uso de impressão 3D para classificar e planejar a cirurgia de fraturas complexas do planalto tibial. Métodos: 54 fraturas complexas do planalto tibial tratadas em nosso hospital de janeiro de 2017 a janeiro de 2019 foram revisadas. Os pacientes foram submetidos a tomografias computadorizadas em espiral pré-operatórias, com dados DICOM processados usando o software Mimics. A tecnologia de impressão 3D gerou modelos precisos em escala 1:1 das fraturas. Estes modelos ajudaram a subdividir as fraturas em sete tipos com base nos planos geométricos do planalto tibial. As abordagens cirúrgicas e as operações simuladas, incluindo a redução da fratura e a colocação de placa, foram planejadas utilizando estes modelos. Resultados: Os modelos 3D representaram com precisão a direção e a extensão da deslocação da fratura e do colapso do planalto. Os modelos facilitaram o planejamento pré-operatório, viabilizando estratégias de reconstrução precisas e a correspondência dos detalhes intraoperatórios com os modelos pré-impressos. Após a cirurgia, a estrutura anatômica do planalto tibial melhorou significativamente em todos os 54 casos. Conclusão: A impressão 3D ajuda na classificação e no planejamento pré-operatório de fraturas complexas do planalto tibial, melhorando os resultados cirúrgicos e a restauração anatômica. Nível de Evidência IV, Estudo Prospectivo.

Bacteria-Like Gaiella Accelerate Soil Carbon Loss by Decomposing Organic Matter of Grazing Soils in Alpine Meadows on the Qinghai-Tibet Plateau.

The alpine meadows of the Qinghai-Tibet Plateau have significant potential for storing soil carbon, which is important to global carbon sequestration. Grazing is a major threat to its potential for carbon sequestration. However, grazing poses a major threat to this potential by speeding up the breakdown of organic matter in the soil and releasing carbon, which may further lead to positive carbon-climate change feedback and threaten ecological security. Therefore, in order to accurately explore the driving mechanism and regulatory factors of soil organic matter decomposition in grazing alpine meadows on the Qinghai-Tibet Plateau, we took the grazing sample plots of typical alpine meadows as the research object and set up grazing intensities of different life cycles, aiming to explore the relationship and main regulatory factors of grazing on soil organic matter decomposition and soil microorganisms. The results show the following: (1) soil microorganisms, especially Acidobacteria and Acidobacteria, drove the decomposition of organic matter in the soil, thereby accelerating the release of soil carbon, which was not conducive to soil carbon sequestration in grassland; (2) the grazing triggering effect formed a positive feedback with soil microbial carbon release, accelerating the decomposition of organic matter and soil carbon loss; and (3) the grazing ban and light grazing were more conducive to slowing down soil organic matter decomposition and increasing soil carbon sequestration.

Outpatient surgery for tibial plateau fractures.

PURPOSE: The purpose of this study was to determine the rates of compartment syndrome and other early complications following outpatient open reduction and internal fixation (ORIF) of tibial plateau fractures. METHODS: This was a retrospective cohort at a single US level I academic trauma centre of patients with tibial plateau fractures managed operatively. Inpatients received their definitive ORIF during their index hospital stay and were admitted post-operatively following ORIF. Outpatients were scheduled for ambulatory surgery during definitive ORIF. Exclusion criteria for outpatient surgery included compartment syndrome, polytrauma, open types IIIb/IIIc, and patients who received any internal fixation during index presentation. The primary outcome measure was post-operative compartment syndrome. Secondary outcomes were return to the 90-day return to the ED, 90-day readmission, surgical wound infection, thromboembolism, and 90-day mortality. An intention-to-treat (ITT) and as-treated (AT) analyses were performed. RESULTS: Totally, 71 inpatients and 47 outpatients were included. There were no cases of post-operative compartment syndrome. In the ITT analysis, there were no differences for inpatients vs outpatients for 90-day re-admission (22.5% vs 12.8%, p = 0.275), 90-day return to the ED (35.2% vs 17.0%, p = 0.052), infection (12.7% vs 2.1%, p = 0.094), DVT (7% vs 4.3%, p = 0.819), or PE 1.4% vs 0.0%, p = 1.000). The AT analysis showed a significantly higher 90-day re-admission (26.9% vs 2.5%, p = 0.003) and 90-day ED visit (38.5% vs 7.5%, p = 0.001) rate in the inpatient group. CONCLUSIONS: Appropriately selected patients with isolated tibial plateau fractures can have non-inferior rates of compartment syndrome and post-operative complications when compared to inpatients.