Nonplanar Aromaticity of Dinuclear Rare-Earth Metallacycles.

While the concept of metalla-aromaticity has well been extended to transition organometallic compounds in diverse geometries, aromatic rare-earth organometallic complexes are rare due to the special (n - 1)d0 configuration and high-lying (n - 1)d orbitals of rare-earth centers. In particular, nonplanar cases of rare-earth complexes have not been reported so far. Here, we disclose the nonplanar aromaticity of dinuclear scandium and samarium metallacycles characterized by various aromaticity indices (nucleus-independent chemical shift, isochemical shielding surface, anisotropy of induced current density, and isomerization stabilization energy). Bonding analyses (Kohn-Sham molecular orbital, adaptive natural density partitioning, multicenter bond indices, and principal interacting orbital) reveal that three delocalized π orbitals, predominantly contributed by the 2-butene tetraanion ligand, result in the formation of six-electron conjugated systems. Guided by these findings, we predicted that the lutetium and gadolinium analogues of dinuclear rare-earth metallacycles should be aromatic, which have been verified by the successful synthesis of real molecules. This work extends the concept of nonplanar aromaticity to the field of rare-earth metallacycles and illuminates the path for designing and synthesizing various rare-earth metalla-aromatics.

Diagnostic delay, treatment duration and outcomes since the implementation of integrated model of tuberculosis control and their associated factors in a county in East China.

OBJECTIVE: This study assesses the diagnostic delay, treatment duration and treatment outcomes of tuberculosis (TB) patients since the implementation of the integrated model of TB control in a county in eastern China. It further identifies factors associated with diagnostic delay and treatment duration in the integrated model. METHODS: We collected data through the Chinese Tuberculosis Information Management System (TBIMS) for Cangnan County in Zhejiang Province. Chi-square and Mann-Whitney tests were adopted to identify factors associated with duration of treatment and treatment delay for TB patients within the integrated model. Multiple regression analysis was subsequently performed to confirm the identified factors. RESULTS: In the integrated model from 2012 to 2018, the median health system delay was maintained at 1 day, and the median patient delay decreased from 14 to 9 days and the median total delay decreased from 15 to 11 days. In addition, the proportion of patients who experienced patient delay > 14 days and total delay > 28 days decreased from 49% to 35% and from 32% to 29% respectively. However, the proportion of patients who had health system delay > 14 days increased from 0.2% to 13% from 2012 to 2018. The median treatment duration increased from 199 to 366 days and the number of TB patients lost to follow-up showed an overall upward trend from 2012 to 2018. The multivariable regression analysis indicated that migrant TB patients and TB patients initially diagnosed in hospitals at the prefectural level and above tended to experience total delay > 28 days (p < 0.001). Linear regression analysis confirmed that new TB patients>60 years tended to have longer treatment duration (p < 0.05). CONCLUSIONS: While our study may suggest the potential of the integrated model in early detection and diagnosis of TB, it also suggests the importance of strengthening supervision and management of designated hospitals to optimize the treatment duration and improve retention of patients in TB care. Enhancing health education for TB patients, especially amongst migrant patients, and training in TB identification and referral for non-TB doctors are also key for early TB detection and diagnosis in the integrated model.

Metal-Ligand Bonds in Rare Earth Metal-Biphenyl Complexes.

A series of theoretical methods, including density functional theory, multiconfiguration molecular orbital theory, and ab initio valence bond theory, are devoted to understanding the metal-ligand bonds in M-BP (BP = biphenyl; M = Sc, Y, or La) complexes. Different from most transition metal-BP complexes, the most stable metal-biphenyl conformers are not half-sandwich but clamshell. Energy decomposition analysis results reveal that the M-BP bonds in the clamshell conformers possess extra-large orbital relaxation. According to the wave function analysis, 2-fold donations and 2-fold back-donations exist in the clamshell M-BP bonds. The back-donations from M to BP are quite strong, while donations from BP to M are quite weak. Our work improves our understanding of the metal-ligand bonds, which can be considered as the "reversed" Dewar-Chatt-Duncanson model.

Delayed diagnosis of tuberculosis in patients with diabetes mellitus co-morbidity and its associated factors in Zhejiang Province, China.

BACKGROUND: Tuberculosis (TB) remains a significant global public health problem. China has the second highest TB burden in the world. With a growing TB population with diabetes mellitus (DM), the TB control system faces mounting challenges. To date, evidence remains inconclusive regarding the association between TB-DM co-morbidity and delayed diagnosis of TB patients. This study aims to assess the diagnostic delay of TB patients with known DM and identify the factors associated with this delay. METHODS: Data was collected from China's Tuberculosis information management system in two counties of Zhejiang province, China. Patient delay, health system delay and total diagnostic delay are defined as follows: 1) the interval between the onset of TB symptoms and first visit to any health facility; 2) from the first visit to the health facility to the confirmed TB diagnosis in the designated hospital; 3) the sum of patient and health system's respective delays. Comparison of these delays was made between TB patients with and without DM using Mann-Whitney U test and Chi-square test. Univariate and multivariate regression analysis was used to identify factors influencing delays among TB patients with DM. RESULTS: Of 969 TB patients, 67 (7%) TB patients had DM co-morbidity. Compared with TB patients without DM, TB patients with DM experienced significantly shorter health system delays (p < 0.05), and there was a significantly lower proportion of patients whose health system delayed> 14 days (7.0% vs. 18%, p < 0.05). However, no significant difference was observed between both patient categories regarding patient delay and total diagnostic delay. The multivariate regression analysis suggested that TB patients with DM who were aged < 60 years (AOR = 3.424, 95%CI: 1.008-11.627, p < 0.05) and non-severe cases (AOR = 9.725, 95%CI: 2.582-36.626, p < 0.05) were more likely to have a total diagnostic delay of> 14 days. CONCLUSIONS: Our study suggests that DM does not contribute to further diagnostic delay as expected. Instead, we observed significantly improved health system delay among TB patients with DM. The findings indicate the importance of early screening and diagnosis for TB among diabetic patients and of strengthening the integrated control and management of TB and diabetic programs.

[Comparison of minimally invasive using a tubular retraction system versus open transforaminal lumbar interbody fusion for the treatment of lumbar degenerative diseases].

OBJECTIVE: To compare the clinical effect of minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) using a tubular retraction system with traditional transforaminal lumbar interbody fusion (TLIF) for the treatment of lumbar degenerative diseases. METHOD: From June 2009 to June 2013, a total of 96 patients in Department of Orthopaedics, Armed Police Jiangxi Corps Hospital, suffering from lumbar degenerative diseases were divided into 2 groups randomly. 42 patients underwent MIS-TLIF using a tubular retraction system. There were 23 males and 19 females with the age of 64.4 ± 4.9. The preoperative diagnosis included lumbar disc herniation with instability (17 cases), lumbar spinal stenosis (13 cases), lumbar degenerative spondylolisthesis (12 cases). 54 patients underwent traditional TLIF. There were 32 males and 22 females with the age of 66.5 ± 7.6. The preoperative diagnosis included lumbar disc herniation with instability (22 cases), lumbar spinal stenosis (17 cases), lumbar degenerative spondylolisthesis (15 cases). The general data, operating time, blood loss and volume of drainage after operation were compared between two groups. VAS, ODI evaluating standards were applied to evaluate the therapeutic effect. The intervertebral fusion were observed by X ray or CT scan. RESULTS: All patients underwent surgery safely without severe complication occurred. There was no significant difference in operation time between MIS-TLIF group (96±37) min and TLIF group (83 ± 25) min, P>0.05; the blood, volume of drainage after operation in MIS-TLIF group were significantly less than TLIF group (P<0.05). The follow-up time was( 26 ± 7) months in MIS-TLIF group and (27 ± 8) months in TLIF group. Compared with preoperative parameters, the scores of VAS and ODI were significantly decreased after surgery and at the final follow-up in both groups (P<0.05). Compared with TLIF group, VAS in MIS-TLIF group of post-operation and the final follow-up were improved, respectively (P<0.05), but there is no significant difference in ODI score. There occurred cage dislocation with no nerve symptom in MIS-TLIF group in 1 case and fat liquefaction in TLIF group in 1 case. At the follow-up after 6.5 months postoperatively, all the operated segments achieved fusion standard and no internal screw were loose or broken. CONCLUSION: MIS-TLIF technique could provide less operation trauma, blood lose and achieve the similar satisfied short-term effect as traditional TLIF.

Design, synthesis, and antitumor activity of novel podophyllotoxin derivatives as potent anticancer agents.

In order to find novel synthetic compounds with superior antitumor activity and overcome multidrug resistance, a series of novel 4ß-N-substituted podophyllotoxin derivatives were synthesized under mild conditions with satisfactory yield. Nine novel podophyllotoxin derivatives were synthesized by linking 4ß-amino-podophyllotoxin with aldehydes via the formation of a Schiff's base, and imines were reducted to secondary amines. These novel derivatives have been evaluated for cytotoxicity against human cancer cell lines Hela, K562, and K562/AO2. The results indicated that these compounds possess superior bioactivity (IC50 values were found at the range of 10(- 6)-10(- 8) mol/l) and weak multidrug resistance.

Comparison of Delay in Tuberculosis Diagnosis Between Migrants and Local Residents in an Eastern County of China: An Analysis of the Electronic Data Between 2015 and 2019.

Introduction: China continues to rank among one of the countries with the highest number of tuberculosis (TB) cases globally. Migrants are a particularly at-risk subgroup for TB and pose a challenge for case management in contemporary China. The early diagnosis and treatment of patients with TB are pivotal for effective TB control. This study investigates the delay in the TB diagnosis of migrants as compared with residents, to provide an evidence base for improved case detection and the better management of migrant patients with TB. Materials and Methods: The data was collected from the Tuberculosis Information Management System (TBIMS) (2015-2019) in an eastern county of China. The total diagnostic delay, consisting of patient delay and health system delay, is defined as the interval between the onset of TB symptoms and the confirmation of TB diagnosis in the designated TB hospital. The comparison of the delay in the TB diagnosis between migrants and residents was conducted using a Mann-Whitney U-test and chi-square test. The difference in the delay curves between these two groups was examined using a log-rank test. Results: Of 2,487 patients with TB, 539 (22%) were migrants. The migrants tended to be younger, presented with less severe conditions, received an initial diagnosis at prefectural and above-level hospitals. Compared with the local patients with TB, the migrant patients with TB had a longer median total diagnostic delay (30 vs. 9, P = 0.000) and a higher proportion of patients with this delay >28 days (52 vs. 13%, P = 0.000). Similarly, the migrant patients with TB also had a longer median patient delay (13 vs. 9, P = 0.000) and a higher proportion of patients with this delay >14 days (47 vs. 30%, P = 0.000), longer median health system delay (9 vs. 0, P = 0.000), and a higher proportion of patients with this delay >14 days (42 vs. 0.5%, P = 0.000) than the local patients with TB. The survival curves of delay showed that the longer the time interval was, the more likely the migrant patients with TB were to be diagnosed (P < 0.05). Conclusions: Diagnosis is significantly delayed among migrant patients with TB. Our study highlights the importance of early screening and diagnosis for TB especially among migrants, to improve access and ensure better management for all patients with TB.