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Gui-you Li,1 Hai-long Tan,1 Pei Chen,1 Hui-Yu Hu,1 Mian Liu,1 Deng-jie Ou-yang,1 Rooh-afza Khushbu,1 Deepak Pun,1 Jin-dong Li,1 Zhi-peng Zhang,2 Qiong Yang,1 Peng Huang,1 Shi Chang1 1Department of General Surgery, Xiangya Hospital, Central South University, Changsha, Hunan, People’s Republic of China; 2Department of Geriatrics, Xiangya Hospital, Central South University, Changsha, Hunan, People’s Republic of ChinaCorrespondence: Peng Huang; Shi ChangDepartment of General Surgery, Xiangya Hospital, Central South University, Changsha, Hunan, People’s Republic of ChinaTel +86 15273124136; +86 13973192319Email xiangyahp@csu.edu.cn; changshi@csu.edu.cnBackground: Therapeutic lateral neck dissection (LND) is recommended in papillary thyroid carcinoma (PTC) patients with clinically lateral lymph node metastasis (LLNM), whether underwent level V LND remains controversial for lacking of sensitive predicting system. BRAFV600E mutation is associated with aggressive tumor behavior, recurrence, and disease-specific mortality of PTC. However, the relationship between BRAFV600E mutation and level V LNM is unclear.Methods: Univariate and multivariate analyses were retrospectively conducted on the potential predictive factors of 252 PTC patients who underwent initial treatment of neck lymph node dissection from September 2015 to October 2018 in our institute. BRAFV600E mutation and the clinicopathological characteristics of the two groups were compared.Results: LLNM was presented in 208 (82.5%) patients and level II–V LNM was present in 42.8%, 71.2%, 85.1%, 17.8% patients, respectively. BRAFV600E mutation was observed in 188 (74.6%) patients and was significantly associated with patients’ age, lymphocytic thyroiditis, capsule invasion, bilateral central lymph node metastasis (CLNM) and level V LNM in PTC. Univariate analysis revealed that lymphocytic thyroiditis, tumor size, number of CLNM, Level II LNM, Level III LNM, simultaneous Level II+III, simultaneous Level III+IV and simultaneous Level II+III+IV were significantly correlated with Level V LNM. In addition, multivariate analysis revealed that tumor size ≥ 2.5 cm, number of CLNM≥ 3, level II metastases and BRAFV600E mutation were independent Level V LNM predictors (odds ratio 3.910, 3.660, 8.410, 0.439; 95% CI 1.737– 10.135, 1.054– 12.713, 1.233– 57.355, 0.280– 0.827, respectively).Conclusion: In summary, we presented several independent predictive factors for level V LNM in PTC patients. We constructed a risk prediction model consisting of tumor size ≥ 2.5 cm, number of CLNM≥ 3 and level II metastases and BRAFV600E mutation that may guide surgeons to evaluate the nodal status in PTC and perform tailored therapeutic LND.Keywords: papillary thyroid carcinoma, BRAFV600E mutation, level V lymph nodes metastasis, pathological features

Qiong Yang,1 Pei Chen,1 Hui-Yu Hu,1 Hai-long Tan,1 Gui-you Li,1 Mian Liu,1 Deng-jie Ou-yang,1 Rooh-afza Khushbu,1 Deepak Pun,1 Zhi-peng Zhang,2 Peng Huang,1 Shi Chang1 1Department of General Surgery, Xiangya Hospital, Central South University, Changsha, Hunan, People’s Republic of China; 2Department of Geriatrics, Xiangya Hospital, Central South University, Changsha, Hunan, People’s Republic of ChinaCorrespondence: Peng Huang; Shi ChangDepartment of General Surgery, Xiangya Hospital, Central South University, Changsha, Hunan, People’s Republic of ChinaTel +86 15273124136Email xiangyahp@csu.edu.cn; changshi@csu.edu.cnBackground: Cervical lymph node metastasis (LNM) is an independent risk factor for poor prognosis of papillary thyroid carcinoma (PTC), but the scope of PTC lateral neck dissection (LND) is controversial. Solitary lateral lymph node metastasis (SLNM) is a special type of PTC with lateral LNM. Currently, study on the preoperative clinical characteristics of SLNM has been seldomly reported. This study evaluated the preoperative characteristics for predicting the SLNM of PTC.Methods: We included 391 patients diagnosed with PTC between May 2011 and July 2017. Among those patients, 44 had SLNM and 347 had multiple lateral neck node metastasis (MLNM). The clinicopathologic characteristics and other central lymph node metastasis risk factors were retrospectively analyzed.Results: Univariate analysis revealed that age and tumor size (≤ 1 cm) were significantly correlated with SLNM. In ROC curve analysis, the optimal cutoff age of preoperative predictors for the prediction of SLNM was 46.5 years (AUC=0.623, 0.536– 0.710). Besides, the frequency and mean number of CLNM was significantly less in the SLNM than MLNM group. The oval and round tumor shape and well-defined margin of the tumor were more common in the SLNM group (p =0.001; p=0.024, respectively). In addition, multivariate analysis revealed that age ≥ 47, capsular invasion, no extrathyroidal extension, with central lymph node metastases and irregular shape were independent SLNM predictors of PTCs (odds ratio 2.386, 0.173, 0.284, 0.239, 0.188; 95% CI 1.07– 5.140, 0.058– 0.840, 0.066– 0.926, 0.091– 0.437, 0.167– 0.864, respectively).Conclusion: This study supported that SLNM is more likely to happen in PTC patients with age ≥ 47 years, capsular invasion, no extrathyroidal extension, with central lymph node metastases and irregular shape. That denotes, selective single level neck dissection can be considered as an alternative to systemic lateral neck dissection in those patients.Keywords: solitary lateral lymph node metastasis, papillary thyroid carcinoma, central lymph node dissection

Abstract: The problem of robust stability in the state space model of linear time-varying systems with time-varying parameter uncertainties is considered. The Lyapunov approach is employed to obtain bounds on the uncertain time-varying parameters to guarantee the stability of the system. The robust stability bounds obtained are not necessarily symmetric with respect to the origin in the parameter space and can significantly reduce the conservatism in the previous results. Sufficient conditions for the stability of the steady-state responses of nonlinear systems (especially of piecewise linear systems) subjected to periodic excitations are proposed by using the results derived. Two numerical examples are used to demonstrate the accuracy of the formulation. [ABSTRACT FROM AUTHOR]

Introduction: ECG changes are associated with regular long-term intensive exercise due to electrical manifestations of increased vagal tone, increased ventricular wall thickness and enlarged chamber size. The aim of this study was to further understand the relationship of athletic ECG changes and athletic performance in an athletic population., Methods: A retrospective cohort study was performed in 195 Nepali civilian males undergoing selection to the Gurkhas. V̇O 2max (maximal oxygen consumption) was estimated from a 1.5-mile run time using Cooper's formula and correlated with athletic ECG adaptations. Variables were explored with univariable and multivariable linear regression., Results: The median number of athletic changes on ECG was 2 (IQR 1-2). There was no significant correlation (p=0.46) between the number of ECG adaptations and the degree of cardiovascular fitness by estimated V̇O 2max (estV̇O 2max ). We found a negligible but significant correlation between the presence of inferior T wave inversion (TWI) and estV̇O 2max (R 2 =0.03, p=0.02). The multivariable-fitted regression model was: estV̇O 2max ~Intercept+presence of RVH (right ventricular hypertrophy) voltage criteria+absence of sinus arrhythmia+T wave axis+inferior TWI. The overall regression was statistically significant: R 2 =0.10, F(df=4, df=189)=[5.4], p=0.0004). All variables in the multivariable model significantly predicted estV̇O 2max (p<0.04)., Conclusion: ECG changes of athleticism negligibly predict and differentiate athletic performance in our athletic population. The most predictive ECG markers being voltage criteria for left ventricular hypertrophy and RVH. Markers of increased vagal tone were not predictive. TWI, being a marker for disease, was also a marker for athletic performance in this cohort. The number of athletic ECG adaptations did not predict increased athletic performance., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. No commercial re-use. See rights and permissions. Published by BMJ.)

Background Insufficient physical activity and poor cardiopulmonary fitness increases the risk of chronic diseases and premature mortality. Sedentary lifestyle is observed among young health science students. Objective To assess cardiopulmonary fitness and physical activity levels among health science students at Jumla. Method A cross-sectional study was conducted on health science students at Karnali Academy, Jumla. Cardiopulmonary fitness was assessed using the Queen's College Step Test to calculate VO2max. International Physical Activity Questionnaire was applied to measure physical activity in terms of Metabolic Equivalent of Task (MET) value. Data analysis utilized GNU-PSPP software with descriptive and inferential statistics. Result Total 107 students participated (56 females), aged 18-37 years. Their median VO2max was 40.05 ml/kg/min, significantly higher in males [51.69 (IQR 45.81 - 57.57)] than females [36.37 (IQR 34.90 - 38.58)] (p<0.001). Median weekly physical activity was 1030 MET-minutes/week, with males reporting higher levels [1436 (962 - 2670)] than females [678 (414 - 1103)] (p<0.001). VO2max had a positive correlation with total MET value per week (r = 0.504, p<0.001), and negative correlation with body adiposity (p<0.02). Multiple linear regression revealed physical activity level, sex, and BMI as significant predictors of VO2max (p<0.01). Conclusion Health science students at Karnali Academy have average levels of cardiopulmonary fitness and physical activity, lower in females. Targeted interventions can improve their fitness, benefiting the wider population in future. Further research should explore barriers to physical activity and factors influencing healthy lifestyle adoption among health science students in this region.

Ziziphus mauritiana Lam. (Rhamnaceae) is a large spiny shrub or small tree, native to the Indian subcontinent that can reach a maximum height of 9-15 m. This plant stands as a renowned tropical fruit variety, commonly recognized as the Indian plum, Desert apple, or Indian Jujube. The objective of this study was to examine the standard physicochemical parameters of Z. mauritiana seed kernel oil and to formulate the ketoconazole soap (2 % w/w), using the obtained oil, as a base. The oil was obtained through hexane extraction from the seed kernels. To formulate pharmaceutical ketoconazole soap, Z. mauritiana seed kernel oil was subjected to a basic saponification reaction using potassium hydroxide. All the examined physicochemical parameters, namely acid value (4.71 mg KOH/g), saponification value (229.18 mg KOH/g), peroxide value (4.15 milliequivalents KOH/g), ester value (224.47 mg KOH/g), iodine value (11.19 mg KOH/g), refractive index (1.448), pH (5.93), viscosity (89 cP), and specific gravity (0.912 g/mL) were within the acceptable range for industrial purposes. The examination of quality control parameters, namely drug content (99.49 %), total fatty matter (71.13 %), foam retention time (17.21 min), foam height (18.56 cm), moisture content (9.14 %), and pH (7.16) indicated that the newly formulated ketoconazole soap complied with the acceptable limits. In summary, our research demonstrated the excellent physicochemical stability of Z. mauritiana seed kernel oil and its suitability as a soap base, supporting its promising prospects for cost-effective production of cosmetics, soaps, and shampoos in the pharmaceutical and cosmeceutical industries, reducing reliance on synthetic bases., Competing Interests: Not applicable., (© 2023 The Authors.)

Background The electrical activities of heart recorded as electrocardiogram (ECG) are mostly done in supine postures. The body postural changes have effects in these electrical activities in heart which needs to be properly recognized. Objective To find the variations in electrocardiogram during postural changes from supine to upright i.e. sitting and standing postures among apparently healthy young adults. Method A cross sectional study was carried out in Manipal College of Medical Sciences after the institutional ethical clearance. The apparently healthy 30 Nepalese male medical students between 18-25 years of age were enrolled. The electrocardiography was elicited in supine, sitting and standing postures in the participants after 5 minutes' interval between each procedure in each participant. Result The highest mean amplitudes of Q wave were seen in sitting postures (0.12±0.04 mm), R wave in standing postures (1.46±0.55 mm) and S wave also in standing postures (0.23±0.2 mm). The mean amplitudes of Q and S waves showed statistically significant difference when compared between supine and upright postures. The maximum QRS duration was found while sitting (0.08±0.01 ms)and maximum heart rate in standing posture (82.43±10.59/min). The mean comparison of heart rate was statistically highly significant when compared between supine and standing postures. The mean QRS frontal axis was comparatively increased while standing (64.30±39.29). Conclusion The electrical activities of heart vary during postural changes among apparently healthy young adults. These changes are most prominent when compared between supine and standing postures which urges for careful interpretation of electrocardiogram if it is done in upright postures.

Background: Therapeutic lateral neck dissection (LND) is recommended in papillary thyroid carcinoma (PTC) patients with clinically lateral lymph node metastasis (LLNM), whether underwent level V LND remains controversial for lacking of sensitive predicting system. BRAF V600E mutation is associated with aggressive tumor behavior, recurrence, and disease-specific mortality of PTC. However, the relationship between BRAF V600E mutation and level V LNM is unclear., Methods: Univariate and multivariate analyses were retrospectively conducted on the potential predictive factors of 252 PTC patients who underwent initial treatment of neck lymph node dissection from September 2015 to October 2018 in our institute. BRAF V600E mutation and the clinicopathological characteristics of the two groups were compared., Results: LLNM was presented in 208 (82.5%) patients and level II-V LNM was present in 42.8%, 71.2%, 85.1%, 17.8% patients, respectively. BRAF V600E mutation was observed in 188 (74.6%) patients and was significantly associated with patients' age, lymphocytic thyroiditis, capsule invasion, bilateral central lymph node metastasis (CLNM) and level V LNM in PTC. Univariate analysis revealed that lymphocytic thyroiditis, tumor size, number of CLNM, Level II LNM, Level III LNM, simultaneous Level II+III, simultaneous Level III+IV and simultaneous Level II+III+IV were significantly correlated with Level V LNM. In addition, multivariate analysis revealed that tumor size ≥2.5 cm, number of CLNM≥3, level II metastases and BRAF V600E mutation were independent Level V LNM predictors (odds ratio 3.910, 3.660, 8.410, 0.439; 95% CI 1.737-10.135, 1.054-12.713, 1.233-57.355, 0.280-0.827, respectively)., Conclusion: In summary, we presented several independent predictive factors for level V LNM in PTC patients. We constructed a risk prediction model consisting of tumor size ≥2.5 cm, number of CLNM≥3 and level II metastases and BRAF V600E mutation that may guide surgeons to evaluate the nodal status in PTC and perform tailored therapeutic LND., Competing Interests: The authors declare that they have no competing interests in this work., (© 2020 Li et al.)

An ice-templating process was used to fabricate polymer/MOF monoliths, specifically chitosan/UiO-66, as adsorbents for water treatment. The ice-templated macropores enhanced mass transport, while the monoliths could be easily recovered from solution. This was demonstrated by the adsorption of methylchlorophenoxypropionic acid (MCPP, a herbicide compound) from dilute aqueous solution. To enhance the stability, the freeze-dried monoliths were treated with NaOH solution, solvent exchanged, and dried. The treated chitosan/UiO-66 monolith achieved an adsorption capacity of 34.33 mg g -1 (a maximum theoretic value of 334 mg g -1 by the Langmuir model), closer to the capacity (36.00 mg g -1 ) of the freshly prepared UiO-66 nanoparticles and much higher than that of the NaOH-washed UiO-66 nanoparticles (18.55 mg g -1 ), by performing the tests in 60 ppm MCPP solution. The composite monolith could be easily picked up using tweezers and used for recycling tests. Over 80% of the adsorption capacity was retained after three more cycles. The powder X-ray diffraction and N 2 sorption studies suggested the crystalline structure of UiO-66 was destroyed during NaOH washing procedure. This, however, provides the potential to improve the adsorption capacity by developing methods to fabricate true polymer/MOF composites.

We have carried out a mechanistic investigation of aerobic dehydrogenation of cyclohexanones and cyclohexenones to phenols with a Pd(TFA)2/2-dimethylaminopyridine catalyst system. Numerous experimental methods, including kinetic studies, filtration tests, Hg poisoning experiments, transmission electron microscopy, and dynamic light scattering, provide compelling evidence that the initial Pd(II) catalyst mediates the first dehydrogenation of cyclohexanone to cyclohexenone, after which it evolves into soluble Pd nanoparticles that retain catalytic activity. This nanoparticle formation and stabilization is facilitated by each of the components in the catalytic reaction, including the ligand, TsOH, DMSO, substrate, and cyclohexenone intermediate.

The dehydrogenation of cyclohexanones affords cyclohexenones or phenols via removal of 1 or 2 equiv of H2, respectively. We recently reported several Pd(II) catalyst systems that effect aerobic dehydrogenation of cyclohexanones with different product selectivities. Pd(DMSO)2(TFA)2 is unique in its high chemoselectivity for the conversion of cyclohexanones to cyclohexenones, without promoting subsequent dehydrogenation of cyclohexenones to phenols. Kinetic and mechanistic studies of these reactions reveal the key role of the dimethylsulfoxide (DMSO) ligand in controlling this chemoselectivity. DMSO has minimal kinetic influence on the rate of Pd(TFA)2-catalyzed dehydrogenation of cyclohexanone to cyclohexenone, while it strongly inhibits the second dehydrogenation step, conversion of cyclohexenone to phenol. These contrasting kinetic effects of DMSO provide the basis for chemoselective formation of cyclohexenones.

Metallation of a variety of α,ω-dienes has been explored with an η(9),η(5)-bis(indenyl)zirconium sandwich compound and an ansa-titanocene dinitrogen complex. The η(9),η(5)-bis(indenyl)zirconium sandwich compound, (η(9)-C(9)H(5)-1,3-Pr(2))(η(5)-C(9)H(5)-1,3-(i)Pr(2))Zr, served as an isolable source of Negishi's reagent and readily formed a kinetic mixture of cis and trans diastereomers of the corresponding zirconacyclopentanes upon diene metallation. For pure hydrocarbon substrates such as 1,6-heptadiene and 1,7-octadiene, an equimolar amount of cis and trans diastereomers were the kinetic products; isomerization to the thermodynamically favoured trans isomers was observed over time at ambient temperature or upon heating to 105 °C, respectively. By contrast, substitution of the methylene or ethylene spacer in the α, ω-diene with a fluorenyl group (e.g. 9,9-diallylfluorene) resulted in exclusive kinetic formation of the trans diastereomer. Amino-substituted dienes were also readily cyclised and one example was characterised by single-crystal X-ray diffraction. Similar studies were also conducted with the ansa-titanocene dinitrogen complex, [Me(2)Si(η(5)-C(5)Me(4))(η(5)-C(5)H(3)-3-(t)Bu)Ti](2)(μ(2),η(1),η(1)-N(2)), and both kinetic and thermodynamic selectivities evaluated. The use of a C(1) symmetric ansa-metallocene increases the number of isomeric possibilities. For diallyl tert-butyl amine, diene metallation was more selective than for the bis(indenyl)zirconium sandwich compound and isomerization was also more rapid. Preliminary functionalisation reactivity for both the zircona- and titanocycles was also explored., (This journal is © The Royal Society of Chemistry 2011)

Aromatic molecules are key constituents of many pharmaceuticals, electronic materials, and commodity plastics. The utility of these molecules directly reflects the identity and pattern of substituents on the aromatic ring. Here, we report a palladium(II) catalyst system, incorporating an unconventional ortho-dimethylaminopyridine ligand, for the conversion of substituted cyclohexanones to the corresponding phenols. The reaction proceeds via successive dehydrogenation of two saturated carbon-carbon bonds of the six-membered ring and uses molecular oxygen as the hydrogen acceptor. This reactivity demonstrates a versatile and efficient strategy for the synthesis of substituted aromatic molecules with fundamentally different selectivity constraints from the numerous known synthetic methods that rely on substitution of a preexisting aromatic ring.

Sodium amalgam reduction of the bis(indenyl)zirconium dihalide complexes, (eta5-C9H5-1-iPr-3-Me)2ZrX2 (X = Cl, Br, I), yielded the corresponding end-on dinitrogen complexes, [(eta5-C9H5-1-iPr-3-Me)2Zr(NaX)]2(mu2, eta1, eta1-N2), with inclusion of 1 equiv of salt per zirconocene. The solid state structures of the chloro and iodo congeners establish short Zr N and elongated N N bonds, consistent with modest to strong activation of the coordinated dinitrogen molecule. Exposure of the N2 compounds to 1 atm of dihydrogen resulted in rapid N H bond formation to yield a hydrido zirconocene hydrazido compound concomitant with salt elimination. These studies establish a new structural type of zirconocene dinitrogen complex and demonstrate that side-on coordination of the N2 ligand in the ground state is not a prerequisite for dinitrogen hydrogenation.

Exposure of the isolable zirconocene sandwich compounds, (eta(5)-C5Me5)(eta(5)-C9H5-1-R(1)-3-R(2))Zr (R(1) = Me, (i)Pr, (t)Bu; R(2) = Me) to one atmosphere of dinitrogen resulted in N2 coordination. X-ray diffraction and NMR spectroscopy establish that the resulting dimeric dinitrogen compounds contain an unusual mu2,eta(2)-bridging indenyl ring and a weakly activated N2 ligand. N2 coordination from the isolable zirconium sandwich compounds is extremely sensitive to the number and size of the indenyl subsituents. Compounds bearing two [(i)Pr] or three methyl substituents are stable as eta(9) sandwich compounds for weeks under dinitrogen likely due to the inability to dimerize through a two-atom N2 bridge. Performing the reduction of (eta(5)-C5Me5)(eta(5)-C9H5-1-R(1)-3-R(2))ZrCl2 (R(1) = (i)Pr, (t)Bu; R(2) = Me; R(1) = R(2) = SiMe3) under an N2 atmosphere produced a different outcome; rare examples of side-on, end-on zirconium dinitrogen compounds were isolated and in one case, crystallographically characterized. Protonolysis studies with weak Brønsted acids were used to evaluate the relative activation of the bridging dinitrogen ligands.

Catalytic dehydrogenation of R(2)NHBH(3) (R = Me, H) promoted by a family of bis(cyclopentadienyl)titanium and bis(indenyl)zirconium compounds is reported; structure-reactivity relationships as a function of cyclopentadienyl and indenyl substituents have been examined.

Treatment of the eta9,eta5-bis(indenyl)zirconium sandwich complex, (eta9-C9H5-1,3-(SiMe3)2)(eta5-C9H5-1,3-(SiMe3)2)Zr, with dialkyl ethers such as diethyl ether, CH3OR (R=Et, nBu, tBu), nBu2O, or iPr2O resulted in facile C-O bond scission furnishing an eta5,eta5-bis(indenyl)zirconium alkoxy hydride complex and free olefin. In cases where ethylene is formed, trapping by the zirconocene sandwich yields a rare example of a crystallographically characterized, base-free eta5,eta5-bis(indenyl)zirconium ethylene complex. Observation of normal, primary kinetic isotope effects in combination with rate studies and the stability of various model compounds support a mechanism involving rate-determining C-H activation to yield an eta5,eta5-bis(indenyl)zirconium alkyl hydride intermediate followed by rapid beta-alkoxide elimination. For isolable eta6,eta5-bis(indenyl)zirconium THF compounds, thermolysis at 85 degrees C also resulted in C-O bond cleavage to yield the corresponding zirconacycle. Both mechanistic and computational studies again support a pathway involving haptotropic rearrangement to eta5,eta5-bis(indenyl)zirconium intermediates that promote rate-determining C-H activation and ultimately C-O bond scission.