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Objectives: This study compared the diagnostic value of 3D T1-weighted (T1W) gradient-echo (GRE) and 2D T1W in-phase and out-of-phase GRE sequences for appendicitis diagnosis in pregnant women. Material and Methods: This retrospective study included 25 pregnant patients with suspected appendicitis who underwent 1.5 Tesla abdominal magnetic resonance imaging and had definitive diagnoses. Four doctors approached four separate imaging groups: A (only T2-weighted image [T2WI] sequences), B (T2WI and 3D T1W GRE sequences), C (T2WI and T1W in-phase and out-of-phase GRE sequences), and D (T2WI, 3D T1W GRE, and T1W in-phase and out-of-phase GRE sequences). The kappa (κ) index was used to compare the appendicitis diagnostic results between groups. The diagnostic value of these sequences in the diagnosis of pregnancy appendicitis was also evaluated. Results: Groups A and C had average consistency with definitive diagnosis (κ = 0.6), lower than Groups B and D (κ= 0.865), indicating a high definite diagnosis consistency. Groups B and D had similarly high sensitivity (80%), specificity (100%), positive predictive value (100%), negative predictive value (95.2%), and accuracy (ACC) (96%), higher than Groups A and C (60%, 95%, 75%, 90.5%, and 88%, respectively). Conclusion: 3D T1W-GRE sequences improve appendicitis diagnosis in pregnancy compared to T2W sequences alone. Adding in and out phase GRE sequences do not increase diagnostic ACC. [ABSTRACT FROM AUTHOR]

High-entropy alloys (HEAs) stand out from multi-component alloys due to their attractive microstructures and mechanical properties. In this investigation, molecular dynamics (MD) simulation and machine learning (ML) were used to ascertain the deformation mechanism of AlCoCrCuFeNi HEAs under the influence of temperature, strain rate, and grain sizes. First, the MD simulation shows that the yield stress decreases significantly as the strain and temperature increase. In other cases, changes in strain rate and grain size have less effect on mechanical properties than changes in strain and temperature. The alloys exhibited superplastic behavior under all test conditions. The deformity mechanism discloses that strain and temperature are the main sources of beginning strain, and the shear bands move along the uniaxial tensile axis inside the workpiece. Furthermore, the fast phase shift of inclusion under mild strain indicates the relative instability of the inclusion phase of hexagonal close-packed (HCP). Ultimately, the dislocation evolution mechanism shows that the dislocations are transported to free surfaces under increased strain when they nucleate around the grain boundary. Surprisingly, the ML prediction results also confirm the same characteristics as those confirmed from the MD simulation. Hence, the combination of MD and ML reinforces the confidence in the findings of mechanical characteristics of HEA. Consequently, this combination fills the gaps between MD and ML, which can significantly save time, human power, and cost to conduct real experiments for testing HEA deformation in practice. [Display omitted] • The yield stress decreases significantly as the strain and temperature increase • Changes in strain rate and grain size have less effect on mechanical properties than changes in strain and temperature. • The ML prediction results also confirm the same characteristics as those confirmed from the MD simulation. • The combination of MD and ML reinforces the confidence in the findings of mechanical characteristics of HEA. • The combination fills the gaps between MD and ML, significantly saving time, human power, and cost to conduct real experiments for testing HEA deformation in practice. [ABSTRACT FROM AUTHOR]

We determined the value of computed tomography perfusion (CTP) for assessing the response of hepatocellular carcinoma (HCC) to transarterial chemoembolization (TACE). 20 post-TACE HCC patients were re-evaluated with contrast-enhanced computed tomography and CTP. Patients with persistent arterial vascularization [non-response (NR)] or those with no arterial vascularization in the mass, but with signs of new nodules, underwent digital subtraction angiography (DSA), which was used to analyze image characteristics and CTP parameters of TACE-treated HCC. 27 post-TACE HCC masses (mean size 4.21 cm, range 2-6.5 cm) were observed in the 20 patients. The values yielded by CTP were 78.30±40.41 mL/min/100g and 33.67±38.74 mL/min/100g for hepatic arterial blood flow (HABF) and 51.40±17.80% and 25.60±26.53% for hepatic arterial fraction (HAF) in the NR group and complete response group, respectively. The NR group's cutoff value of HABF was =55.95 mL/min/100g, with a sensitivity of 91.7% and specificity of 71.42%, and that of HAF was =32.55%, with a sensitivity of 92.3% and specificity of 83.33%. The CTP and DSA techniques showed high agreement in assessing the post-TACE responses of liver tumors (κ=0.872). The perfusion parameters HABF and HAF have high value for assessing post-TACE responses of HCC. [ABSTRACT FROM AUTHOR]

The stabilization of ruthenium nanoparticles is achieved by using for the first time multiple donor coordination site-type ligands, the N-phosphanylamidines . These ligands, in which the donor sites are directly connected to one another, lead to the formation of small ruthenium nanoparticles in the size range 1.7–3.1 nm that display narrow size distributions and a hexagonal close packed crystalline structure of ruthenium bulk. The characterization of these new samples by a combination of techniques gives information on the surface state of the particles such as the coordination mode of the ligand and the presence of hydrides. CO molecules can also coordinate suggesting that the surface of the particles is not saturated. This work confirms the interest of screening novel ligands for the synthesis of metal nanoparticles and more particularly, of studying their coordination to probe metal nanoparticles' surface properties. [ABSTRACT FROM AUTHOR]

Abstract: A simple and efficient method for the preparation of N-phosphonio formamidine derivatives of the general formula [R”2N−C(H)=N−P(R’)R2]+X− is described. The data recorded in solution and the single crystal X-ray studies revealed that these compounds are best described by the combination of the two mesomeric N-phosphonio formamidine [R”2N−C(H)=N−P(R’)R2]+ and iminium phosphazene [R”2N=C(H)−N=P(R’)R2]+ forms. Formamidine phosphorus ylides i Pr2N−C(H)=N−P(CH2)R2 were prepared after addition of t BuLi at –78°C from the corresponding N-phosphonio compounds. [(PhCN)2Pd(Cl)2] was reacted with i Pr2N−C(H)=N−P(CH2) i Pr2 to form the dimeric complex [( i Pr2N−C(H)=N−P(CH2) i Pr2)Pd(Cl)(μ-Cl)]2 which was structurally characterized by X-ray analysis. The deprotonation reactions conducted on [ i Pr2N−C(H)=N−PPh3]+X− occurred via an intramolecular rearrangement to give the cyanamide compound i Pr2N−C≡N and PPh3; transient formation of the amino-phosphazene-carbene i Pr2N−C−N=PPh3 was not observed. [Copyright &y& Elsevier]

The study evaluates chronic subdural hematoma (cSDH) middle meningeal artery (MMA) embolization efficacy and safety. A prospective interventional study was conducted in Viet Duc Hospital from November 2021 to April 2024. All consecutive cSDH MMA embolization patients were included. Clinical and imaging data were collected before and one month after treatment. The study included 31 42-cSDH patients. Of these, 25.8% had hematoma evacuation, 83.9% were treated with surgery and embolization, and 16.1% with embolization alone. 92.9% of procedures used polyvinyl alcohol particles. The success rate was 92.9% and complications 7.1%. Asymptomatic external carotid artery vasospasm and MMA rupture occurred. Functional improvement occurred in 91.7% of patients one month after treatment. Significantly lower mean modified Rankin Scale (mRS) score (0.2±0.7 vs. 1.7±0.9; P=0.000) and higher proportion of patients with =2 mRS score (95.8% vs. 74.1%) were observed after treatment. Hematoma thickness decreased significantly (P=0.00) from 21.5±7.9 mm to 8.3±4.1 mm. The midline shift decreased significantly from 7.4±5.0 mm to 0.7±1.2 mm (P=0.00). Just one patient (4.2%) needed surgery. MMA embolization alone or with surgery appears to treat cSDH safely and effectively. [ABSTRACT FROM AUTHOR]

Objective: Arteriovenous malformations (AVMs) are aggressive diseases with a high tendency to recur. AVM treatment is complex, especially in the anatomically difficult head and neck region. This study analyzed correlations between extracranial head and neck AVM presentations and the frequency of recurrence. Methods: We retrospectively assessed AVM recurrence among 55 patients with head and neck AVMs treated with embolization and resection between January 2008 and December 2015. Recurrence was defined as any evidence of AVM expansion following embolization and resection. Patient variables, including sex, age, AVM size, AVM location, stage, and treatment modalities, were examined for correlations with the recurrence of head and neck AVMs. Statistical analysis was performed using SPSS 20.0. Results: A total of 55 patients with at least 6 months of follow-up following AVM treatment with embolization and surgical resection were enrolled in this study. During follow-up, 14 of 55 patients experienced recurrence (the long-term recurrence rate was 25.5%). Sex, stage, AVM size, and treatment modality were identified as independent predictors of recurrence. Recurrence was less likely following the treatment of lower-stage or smaller lesions and did not correlate with age or location. Conclusions: AVMs of the head and neck are among the most challenging conditions to manage due to a high risk of recurrence. Early and total AVM resection is the best method for preventing recurrence. [ABSTRACT FROM AUTHOR]

The present retrospective study aimed to investigate the diagnostic capacity of and design a diagnostic algorithm for dynamic susceptibility contrast-enhanced MRI (DSCE-MRI) and proton magnetic resonance spectroscopy (1H-MRS) in grading low-grade glioma (LGG) and high-grade glioma (HGG). This retrospective study enrolled 57 patients, of which 14 had LGG and 43 had HGG, five had World Health Organization grade 1, nine had grade 2, 20 had grade 3 and 23 had grade 4 glioma. All subjects underwent a standard 3T MRI brain tumor protocol with conventional MRI (cMRI) and advanced techniques, including DSCE-MRI and 1H-MRS. The associations of grade categorization with parameters in tumor and peritumor regions in the DSCE-MRI were examined, including tumor relative cerebral blood volume (TrCBV) and peripheral relative (Pr)CBV, as well as Tr and Pr cerebral blood flow (CBF) and 1H-MRS, including the creatine (Cr) and N-acetyl aspartate (NAA) ratios of choline (Cho), i.e. the TCho/NAA, PCho/NAA, TCho/Cr and PCho/Cr metabolite ratios. The data were compared using the Mann-Whitney U-test, independent samples t-test, Chi-square test, Fisher's exact test and receiver operating characteristic curve analyses. Decision tree analysis established an algorithm based on cutoffs for specified significant parameters. The PrCBF had the highest performance in the preoperative prediction of histological glioma grading, followed by the TrCBV, PrCBF, TrCBV, PCho/NAA, PCho/Cr, TCho/NAA and TCho/Cr. An algorithm based on TrCBV, PrCBF and TCho/Cr had a diagnostic accuracy of 100% for LGG and 90.7% for HGG and a misclassification risk of 7%. The cutoffs (sensitivity and specificity) were 2.48 (86 and 100%) for TrCBV, 1.26 (83.7 and 100%) for PrCBF and 3.18 (69.8 and 78.6%) for TCho/Cr. In conclusion, the diagnostic algorithm using TrCBV, PrCBF and TCho/Cr values, which were obtained from DSCE-MRI and 1H-MRS, increased diagnostic accuracy to 100% for LGGs and 90.7% for HGGs compared to previous studies using conventional MRI. This non-invasive advanced MRI diagnostic algorithm is recommended for clinical application for constructing preoperative strategies and prognosis of patients with glioma. [ABSTRACT FROM AUTHOR]

B Conclusion: b Using liver hanging tape and selective hepatic pedicle control make segment 1, 4 resection become more safe and easier. We should consider to change from isolation segment 1 resection to segment 1 and 4 resection for large size tumour or suspicious for invading middle hepatic vein. [Extracted from the article]

Objectives: This study aimed to define variations in radiological C1 and C2 measurements among Vietnamese subjects and to determine the feasibility of implementing C1-2 fixation techniques. Material and Methods: From October 2017 to April 2018, 120 patients underwent thin slide computed tomography (CT) scans of the cervical spine, in our hospital. Various dimensions of the C1 and C2 were analyzed, using axial and sagittal reconstructions of CT images. Differences in characteristics between the two sides and between sexes were investigated, using Student's t-test, with significance at P < 0.05. Results: The mean anteroposterior dimension and the transverse width of the C1 lateral mass were 19.7 ± 2.1 mm and 12.2 ± 1.7 mm, respectively. The mean angles of the screw, directed to the maximal medial, lateral, cranial, and caudal directions, were 36.6 ± 2.8°, 28.2 ± 3.0°, 49.6 ± 4.1°, and 26.4 ± 5.5°, respectively. The average isthmus height, internal height, and pedicle width of the C2 were 5.8 ± 1.0 mm, 4.8 ± 1.3 mm, and 5.0 ± 1.3 mm, respectively. No significant differences were observed for any parameters, between the left and right side of the C1 or C2 or between the two sexes. Conclusion: This study revealed that the morphology of the C1 and C2 did not differ between genders in the studied subjects, but morphologic variations exist between Vietnamese subjects and other populations. Preoperative anatomy evaluations based on CT data are essential be performed for screw placement and trajectory planning to avoid neurovascular complications and to enhance the treatment outcome. [ABSTRACT FROM AUTHOR]

Background: Bowel and mesenteric injuries have high morbidity and mortality rates in the trauma group due to non-specific symptoms and are often obscured in the context of multiple traumas, contributing to an increased risk of peritonitis and sepsis. The purpose of this research was to assess the diagnostic accuracy of 16-slice multidetector computed tomography (MDCT) findings in the diagnosis of bowel and mesenteric injuries accompanied by the association of these findings with the treatment strategy. Methods: A retrospective study was performed on 86 blunt-abdominal-trauma patients, hospitalized at the emergency department of our institution from June 2018 to July 2019 (75 men and 11 women aged 4-76 years old with a median age of 40.88), who had 16-slice MDCT diagnosis of blunt bowel and mesenteric injuries and were treated by nonsurgical and surgical treatment. Ethical clearance was taken from the institute ethics committee with waiver of consent. Results: The specificity of bowel-wall rupture, active extravasation, and reduced bowel-wall enhancement were 100%, 98.15%, and 100%, respectively. Pneumoperitoneum had the highest sensitivity of 83.33%. Bowel-wall rupture, Janus signs, pneumoperitoneum, and mesenteric stranding were significantly correlated with surgical results. The existence of these results improved the likelihood of 7-, 6-, 29- and 3-fold surgical treatment, respectively. Inter-observer consensus was very strong for bowel-wall rupture, active extravasation, bowel hematoma, and pneumoperitoneum. Conclusion: Bowel-wall rupture was the definite sign of bowel injury and its connection with surgical treatment was important. Pneumoperitoneum was not a specific indication of blunt bowel injury; but when this is detected, emergency intervention should be suggested. [ABSTRACT FROM AUTHOR]

Background: This study aimed to evaluate the diagnostic function of 3-Tesla (T) magnetic resonance imaging (MRI) during the assessment of brachial plexus injury (BPI), in comparison with intraoperative findings. Methods: A retrospective study was performed on 60 patients (47 men and 13 women), who had clinical manifestations of BPI, underwent 3T MRI of the brachial plexus, and were surgically treated at the Viet Duc and Vinmec Times City hospitals, in Hanoi, Vietnam, from March 2016 to December 2019. Preganglionic and postganglionic lesion features were identified on MRI. The diagnostic function of MRI features for the determination of BPI was evaluated and correlated with intraoperative findings. Results: The root avulsion and pseudomeningocele preganglionic injuries were observed in 57% and 43% of MRIs, respectively, and were commonly observed at the C7 and C8 roots. Nerve disruption and never edema were observed in 47.56% and 33.53% of MRIs, respectively, and were commonly observed at the C5 and C6 roots. The sensitivity, specificity, accuracy, positive prognostic value, and negative prognostic value of 3T MRI were 64.12%, 92.90%, 80.33%, 87.50%, and 76.96%, respectively, for the diagnosis of total avulsion, and 68.52%, 83.33%, 80.67%, 47.44%, and 92.34%, respectively, for the diagnosis of nerve disruption. Conclusion: MRI offers valuable details regarding the location, morphology, and severity of both preganglionic and postganglionic injuries during the preoperative diagnosis of BPI. However, this modality played a moderate diagnostic role. Therefore, 3T MRI should be used as a supplemental evaluation, coupled with clinical tests and electromyography, to determine the most appropriate treatment strategies for BPI patients. [ABSTRACT FROM AUTHOR]

B Introduction: b Caudate lobe resection is a difficult and challenging operation even with hepatobiliary surgeons because of its deep location in the hepatic parenchyma and vascular involvement (beneath the root of hepatic veins, above the confluence of hepatic pedicle and in front of the inferior vena cava). Among these, 14 patients resected due to malignant solitary tumour (12 hepatocellular carcinoma patients, 1 cholangiocarcinoma patient and 1 colorectal liver metastasis patient). B Conclusion: b For radical liver resection, the resection of caudate lobe malignant tumour could be carried out the isolated caudate lobe resection (partial or complete) or in combination with other portions of liver and should be based on the location, size and vascular involvement. [Extracted from the article]