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The Nyainqentanglha Metallogenic Belt (NMB) is an economically important lead-zinc ore province located in the Central and Southern Lhasa subterrane, Tibet. The NMB consists mainly of skarn-type lead-zinc polymetallic deposits that form at the contact between Late Cretaceous-Eocene intrusive rocks and carbonatite/volcanic-sedimentary strata. These deposits are generally considered to be related to S-type granites formed by the Indo-Asian continental collision. However, the εHf(t) (ave. −1.6) of zircons from the mineralization-related granitoids indicates that it is crust-mantle mixing products. In addition, the volcanic rocks of the Dianzhong Formation, which have a close spatio-temporal relationship with the skarn-type deposits, typically show mantle-derived features. Therefore, the occurrence of AFC processes in mantle-derived material passing through the thick basement of the Lhasa Terrane may better explain the genesis of the mineralization-related granitoids. In this study, we present results on zircon U–Pb ages, major and trace elements of the granitoids associated with skarn-type mineralization from the Narusongduo district. LA-ICP-MS zircon U–Pb dating shows that the granite formed in the Paleocene (58.6 ± 0.5 Ma). Combined with published regional data, we propose the mineralization age of the skarn-type deposits in the NMB ranges from the Late Cretaceous to Eocene. Detailed petrology and geochemistry of mineralization-related granitoids are evaluated to constrain the magmatic evolution process. The granitoids have high contents of SiO2 (mean 72.8 %), K2O (mean 4.0 %), Rb (mean 186.9 ppm), DI (differentiation index) 84.7, A/CNK (mean 1.3), and low contents of MgO, TFe, suggesting that the granitoids have undergone strong differentiation. In addition, the continuous decrease of P2O5 with progressive differentiation and the lower average P2O5 abundance suggest that the mineralization-related granitoids belong to the I-type granite. The results suggest that the mineralization-related granitoids in the NMB originated from the mantle and is the fractionated I-type granite formed by the process of AFC (Assimilation and Fractional Crystallization). Considering that Pb and Zn often coexist in deposits, we suggest that magmatic differentiation may play an important role in the formation of the granite-related Pb and Zn mineralization.

Nanhong agate, esteemed for its vivid color and natural shine, is experiencing a scarcity in supply despite its high demand. The primary deposits of agate, typically found near the surface, have not been extensively explored due to the predominance of traditional manual excavation methods. This research examined the Nanhong agate deposits in the Zhaojue–Meigu region of Liangshan, China, employing the integration of geological and geophysical surveys. Field geological surveys allowed us to outline the general areas where agate is found. Following this, using magnetic surveys, vertical electrical sounding, and controlled-source audio magnetotellurics, agate deposits were located within the conglomerate layer of the second member of the Feixianguan Formation from the Lower Triassic period at depths of less than 100 m. Our results identify mineralized layers, Xuanwei Formation mudstone, and the underlying bedrock, thus supporting the creation of a mineral prediction map. This research provides essential insights and guidance for agate exploration and the development of associated mineral resources. [ABSTRACT FROM AUTHOR]

Purpose: To compare the safety and efficacy of percutaneous (PEVAR) vs open femoral access (OFA) techniques for endovascular aneurysm repair (EVAR).Methods: A systematic review of English-language articles (Medline, EMBASE, and Cochrane databases) between January 1999 and August 2016 returned 11 studies including 1650 patients with 2500 groin accesses eligible for the meta-analysis. Data extracted from each study were synthesized to evaluate technical success rates, procedure time, and complications for the 2 access approaches. Data are presented as the odds ratio (OR) or mean difference (MD) with 95% confidence intervals (CI). The quality of individual studies was evaluated based on the Newcastle-Ottawa scale.Results: The mean technical success rate in the PEVAR group was 94.5% (785/831). The overall OR was 0.38 (95% CI 0.12 to 1.18, p=0.09), indicating no significant difference between the methods. The procedure time in PEVAR was shorter than OFA (mean difference -24.52, 95% CI -46.45 to -22.60, p<0.001). Overall, the total complication rate was 15.3% in the OFA group vs 7.8% in the PEVAR group (OR 0.52, 95% CI 0.37 to 0.73, p<0.001). The meta-analysis identified significant differences between groups for all complications (p<0.001) and the following individual adverse events: wound infection (OR 0.28, 95% CI 0.10 to 0.81, p=0.02), pseudoaneurysm (OR 8.07, 95% CI 1.54 to 42.32, p=0.01), seroma (OR 0.10, 95% CI 0.02 to 0.55, p=0.008), and lymphocele or lymph leak (OR 0.19, 95% CI 0.04 to 0.92, p=0.04).Conclusion: PEVAR had a similar technical success rate, shorter procedure time, and lower complication rate compared with OFA. Thus, percutaneous access appears to be the preferential approach for EVAR. However, larger and randomized studies are needed to draw definitive conclusions. [ABSTRACT FROM AUTHOR]

Objective: Acute mesenteric artery obstruction is a severe cause of acute mesenteric ischemia, associated with significant morbidity and mortality. However, there is limited guidance on choosing between traditional and minimally invasive techniques comprehensively. This study introduces a selective, minimally invasive strategy designed to improve the survival and prognosis of patients with acute superior mesenteric artery obstruction., Methods: In this prospective, single-arm trial conducted between 2020 and 2023, patients with acute mesenteric ischemia due to acute superior mesenteric artery obstruction were enrolled. A total of 42 patients were included, meeting the predetermined sample size. The primary outcome was the 30-day chronic intestinal failure (CIF)-free survival rate. Based on an algorithm incorporating preoperative radiographic findings, physical signs, and laboratory markers, patients were assigned to one of three therapeutic pathways: traditional laparotomy with thrombectomy, laparoscopy combined with endovascular therapy, or endovascular therapy alone., Results: The CIF-free survival rates at 30 days and 2 years were 71% (30/42) and 60%, respectively. Short-term mortality, including 30-day and in-hospital mortality, was 11.9%, indicating an improvement compared to historical cohorts. The cumulative mortality rates at 6 months, 1 year, and 2 years were 26%, 32%, and 32%, respectively. The primary and assisted patency rates at 1 year were 90% and 97%, respectively. Transition to laparotomy was required in 43% of patients undergoing laparoscopic exploration. Improved blood supply was observed in 73% of the patients who underwent two laparoscopic procedures (15 patients), and bowel resection was avoided in 40% of cases. The median durations of hospitalization and intensive care unit stay were 19 days (IQR 11-31) and 2 days (IQR 0-6), respectively., Conclusions: This selective, minimally invasive strategy for managing acute mesenteric ischemia demonstrated high 30-day CIF-free survival rates and reduced short-term mortality. These findings suggest the potential advantages of this approach in improving outcomes for patients with acute mesenteric ischemia., (Copyright © 2025. Published by Elsevier Inc.)

Background: This cross-sectional study sought to explore the possible risk factors assessed with magnetic resonance (MR) vessel wall imaging for hemodynamic instability (HI) during carotid artery stenting (CAS)., Methods: Patients with carotid stenosis who were referred for CAS from January 2017 to December 2019 were recruited and underwent carotid MR vessel wall imaging. The vulnerable plaque features, including lipid-rich necrotic core (LRNC), intraplaque hemorrhage (IPH), fibrous cap rupture, and plaque morphology, were evaluated. The HI was defined as a drop of systolic blood pressure (SBP) of ≥30 mmHg or the lowest SBP measurement of <90 mmHg after stent implantation. The carotid plaque characteristics were compared between the HI and non-HI groups. The association between carotid plaque characteristics and HI was analyzed., Results: A total of 56 participants (mean age 68.7±8.3 years; 44 males) were recruited. Patients in the HI group (n=26, 46%) had a significantly greater wall area [median 43.2 (IQR, 34.9-50.5) vs. 35.9 (IQR, 32.3-39.4) mm 2 ; P=0.008], total vessel area (79.7±17.2 vs. 69.9±17.3 mm 2 ; P=0.03), prevalence of IPH (62% vs. 30%; P=0.02), prevalence of vulnerable plaque (77% vs. 43%; P=0.01), and volume of LRNC [median 344.7 (IQR, 155.1-665.7) vs. 103.1 (IQR, 53.9-162.9) mm 3 ; P=0.001] in carotid plaque compared to those in non-HI group (n=30, 54%). Carotid LRNC volume (OR =1.005, 95% CI: 1.001-1.009; P=0.01) and presence of vulnerable plaque (OR =4.038, 95% CI: 0.955-17.070; P=0.06) were significantly and marginally associated with HI, respectively., Conclusions: Carotid plaque burden and vulnerable plaque features, particularly a larger LRNC, might be effective predictors for HI during the CAS procedure., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://qims.amegroups.com/article/view/10.21037/qims-22-865/coif). The authors have no conflicts of interest to declare., (2023 Quantitative Imaging in Medicine and Surgery. All rights reserved.)

Objective: To evaluate the use of percutaneous mechanical thrombectomy in the treatment of acute deep venous thrombosis., Methods: Eight cases of acute deep venous thrombosis were reviewed who had received percutaneous mechanical thrombectomy from January to July, 2015 in Beijing Tsinghua Changgung Hospital. All cases were diagnosed as iliofemoral venous thrombosis, 2 cases with vena cava thrombosis. All cases received anticoagulation treatment for 3 to 6 months and pressure treatment after the procedure. Every patient was scheduled to follow up at 1, 3, 6 months, respectively., Results: Technical success were achieved in all cases with restoring of good flow in previous lesions. Grade Ⅲ (complete) lysis was achieved in 2 cases and grade Ⅱ(50%-99% ) lysis in 6 cases, swelling legs were mostly fade away. Of all study follow up , only one case with mild post-thrombotic syndrome after six months., Conclusion: Percutaneous mechanical thrombectomy is safe and effective in the treatment of acute deep venous thrombosis.

Objective: To evaluate the perioperative complications and effectiveness of carotid endarterectomy (CEA) with diabetes mellitus (DM)., Methods: A total of 148 patients with carotid stenosis undergone CEA from December 2010 to December 2013 were collected and analyzed retrospectively. The patients were distributed into DM group (n=83) and the control group (n=65) according to the comorbidities. Age, gender, risk factors, stenosis degree, cerebral ischemic symptom, shunt in operation, perioperative complications and restenosis after one year in the two groups were analyzed and compared., Results: There were no statistical difference between the two groups in terms of the general characteristic, clinical ischemic symptoms, concomitant disease, operative time, the amount of bleeding, the ratio of shunt (P>0.05). The rates of perioperative complications observed in DM group, including postoperative infection, neck hematoma, cranial nerves injured, acute cardiac infarction, stroke, hyperperfusion syndrome, all-cause mortality and one year restenosis after operation were 7.2%, 12.0%, 10.8%, 3.6%, 6.0%, 9.6%, 2.4% and 9.6% respectively. The complication rates observed in the control group, on the other hand were 3.1%, 9.2%, 4.6%, 1.5%, 4.6%, 7.7%, 1.5% and 3.1% respectively. There were no significant statistical difference between the two groups (χ² =0.551, 0.300, 1.898, 0.069, 0, 0.172, 0.138, 1.559, P>0.05)., Conclusion: CEA may be safe and effective in diabetic patients suffering from carotid stenosis, on the condition that the blood glucoses of the patients are controlled well, and the cardio cerebral vascular system is carefully assessed and intervened before the operation.