Analysis of Factors Associated with Cough Persistence After Thoracoscopic Lung Cancer Resection in Elderly Lung Cancer Patients and Discussion of Prevention Strategies.

Objective: The aim was to investigate the factors associated with cough persistence after thoracoscopic lung cancer resection in elderly lung cancer patients and preventive strategies. Methods: In this study, 103 elderly patients with lung cancer who attended the department of thoracic surgery of our hospital from March 2019 to January 2023 were selected for retrospective analysis, all of whom underwent thoracoscopic lung cancer resection and were divided into the cough group (n = 37) and the no-cough group (n = 66) based on the presence or absence of persistent cough in the postoperative period. The clinical data of the patients were analyzed using univariate analysis and multifactorial logistic regression analysis. Results: The findings of the study show that there was no statistically significant difference when comparing the data of the two groups in terms of gender, age, history of diabetes mellitus, history of hypertension, pathologic type, TNM stage, intraoperative blood loss, and postoperative pleural fluid (P > .05). However, multifactorial analysis showed that preoperative history of smoking, the side of the operation being the right side, the extent of the operation being the lobes of the lungs, the time of tracheal intubation ≥172 min, the peritracheal lymph node clearance, and the occurrence of postoperative acid reflux were independent risk factors for the occurrence of persistent cough in patients after thoracoscopic lung cancer resection, while preoperative respiratory training was a protective factor (P < .05). Conclusion: There are many factors affecting persistent cough after thoracoscopic lung cancer resection. These factors need to be paid close attention to in the clinic and preventive measures should be taken to minimize the occurrence of persistent cough and promote postoperative recovery.

Studies on the Light-Induced Phase Transition of CsPbBr3 Metal Halide Perovskite Materials.

We investigate the internal mechanism of the light-induced phase transition of CsPbBr3 perovskite materials via density functional theory simulations. Although CsPbBr3 tends to appear in the orthorhombic structure, it can be changed easily by external stimulus. We find that the transition of photogenerated carriers plays the decisive role in this process. When the photogenerated carriers transit from the valence band maximum to conduction band minimum in the reciprocal space, they actually transit from Br ions to Pb ions in the real space, which are taken away by the Br atoms with higher electronegativity from Pb atoms during the initial formation of the CsPbBr3 lattice. The reverse transition of valence electrons leads to the weakening of bond strength, which is proved by our calculated Bader charge, electron localization function, and integral value of COHP results. This charge transition releases the distortion of the Pb-Br octahedral framework and expands the CsPbBr3 lattice, providing possibilities to the phase transition from the orthorhombic structure to tetragonal structure. This phase transition is a self-accelerating positive feedback process, increasing the light absorption efficiency of the CsPbBr3 material, which is of great significance for the widespread promotion and application of the photostriction effect. Our results are helpful to understand the performance of CsPbBr3 perovskite under a light irradiation environment.

Studies on the photoelectronic properties of a manganese (Mn)-doped lead-free double perovskite.

Taking Cs2NaBiCl6, Cs2AgInCl6 and Cs2AgBiCl6 as examples of lead-free double perovskites (DPs), we study the photoluminescence (PL) properties of Mn-doped DPs. The electron localization function (ELF) reveals the more ionic nature of the Na-Cl bond in Cs2NaBiCl6 than that of the Ag-Cl bond in Cs2AgBiCl6. Bader charge calculations confirm the nominal +2 valence state of Mn ions in both DPs. Mn2+ ions introduce two defect levels in the band gap of the Cs2NaBiCl6 host, accounting for the d-d transition (4T1-6A1 transition) of Mn2+ and thus the subsequent orange PL. The changes of the crystal field and their influences on the emission energy of Mn2+ ions in different DPs are evaluated by calculating the Racah parameters (B and C) and the crystal field strength (Dq) obtained from energies of the terms of d5 in the Cs2NaBiCl6:Mn2+ and Cs2AgInCl6:Mn2+ systems. The results show that Dq in Cs2AgInCl6:Mn2+ is stronger than that in Cs2NaBiCl6:Mn2+. The analyses on bonding interactions of the Mn-Cl bond via ELF and the integrated projected pCOHP also confirm the stronger ionic bonding interactions and thus the boost of the crystal field strength in the Cs2AgInCl6:Mn2+ system, which results in the blue-shift of the Mn2+ introduced PL peak from Cs2AgInCl6 to Cs2NaBiCl6. Our results provide a new strategy to modulate the emission wavelengths, i.e., tuning the crystal field.

The Prevalence of HIV-infected Patients with Virological Suppression but a CD4+ T-cell Count of ≤ 200 Cells/mm3 after Highly Active Antiretroviral Therapy Initiation: A Meta-analysis.

Highly active antiretroviral therapy (HAART) strongly inhibits HIV replication. However, many patients show suboptimal immune recovery (SIR), as defined by virological suppression (i.e. low viral load) with a CD4+ T-cell count of ≤ 200 cells/mm3, after HAART initiation. Here, we performed a systematic evaluation of the SIR prevalence among HIV-infected patients in cohort studies. We searched PubMed, Cochrane Library, Embase, CNKI, Wanfang database, and Chinese Biomedicine Database for cohort studies about HIV-infected participants whose CD4+ T-cell count was ≤ 200 cells/mm3 but still had virological suppression after HAART initiation. The SIR prevalence from each of those cohort studies was pooled into a random-effect meta-analysis. We obtained two kinds of pooled post-HARRT initiation SIR prevalence: one among participants with virological suppression (11 cohort studies involving 18,672 participants), and the other among all HIV-infected participants (seven cohort studies involving 12,063 participants). The pooled SIR prevalence among HIV-infected patients with virological suppression after HAART initiation was 43% (95% confidence interval [CI], 34-51%) at 6 months post-HAART initiation and 10% (95% CI, 5-18%) at 36 months post-HAART initiation; among all HIV-infected patients after HAART initiation, it was 17% (95% CI, 0-55%) and 5% (95% CI, 2-10%) at 6 and 36 months post-HAART initiation, respectively. The SIR prevalence among HIV-infected patients is high at 6 months post-HAART initiation, but its prevalence gradually reduces over time under continuous HAART. Thus, it is important to follow-up on variations in the CD4+ T-cell count and viral load.

Abnormal bone mineral density and bone turnover marker expression profiles in patients with primary spontaneous pneumothorax.

BACKGROUND: To examine the bone mineral density (BMD) and the role of bone biomarkers, including bone formation marker procollagen type I aminoterminal propeptide (PINP) and N-terminal midmolecule fragment osteocalcin (N-MID), bone resorption marker b-C-telopeptides of type I collagen (b-CTX) and tartrate-resistant acid phosphatase 5b (TRACP5b) in the pathogenesis of PSP. METHODS: Eighty-three consecutive primary spontaneous pneumothorax (PSP) patients (PSP group) and 87 healthy individuals (control group) were enrolled in this study. General data, including gender, age, height, weight, and body mass index (BMI), were recorded. Dual-energy X-ray absorptiometry, electrochemiluminescence immunoassay (ECLIA), and ELISA were used to evaluate bone mineral density and expression levels of bone metabolism markers, including PINP, b-CTX, TRACP5b, N-MID, and 25-hydroxyvitamin D (25-OH VD). RESULTS: Mean height was significantly greater in the PSP group compared with the control group, whereas weight and BMI were lower. Patients in the PSP group had significantly lower average bone mineral density, which mainly manifested as osteopenia (11/12, 91.7%); however, only one patient (8.3%) developed osteoporosis. Serum overexpression of PINP, b-CTX, TRACP5b, and N-MID were found in PSP patients. Expression of 25-OH VD was low in PSP patients. Bone resorption markers showed positive linear relationships with bone formation markers in all participants; whereas only TRACP5b expression negatively correlated with 25-OH VD. Expression levels of all bone turnover markers negatively correlated with BMI. Regression analysis identified risk factors of PSP as age, height, weight, and TRACP5b and 25-OH VD expression levels; whereas gender and PINP, b-CTX, and N-MID expression levels were not significantly associated with the onset of PSP. CONCLUSIONS: It had lower bone mineral density in PSP patients. Bone formation marker PINP, N-MID and bone resorption marker b-CTX, TRACP5b were upregulated in PSP patients. 25-OH VD expression was relatively low in this population of PSP patients. Age, height, weight, and expression levels of TRACP5b and 25-OH VD may be risk factors for PSP.

The surface termination effect on the quantum confinement and electron affinities of 3C-SiC quantum dots: a first-principles study.

In light of the established differences between the quantum confinement effect and the electron affinities between hydrogen-passivated C and Si quantum dots, we carried out theoretical investigations on SiC quantum dots, with surfaces uniformly terminated by C-H or Si-H bonds, to explore the role of surface terminations on these two aspects. Surprisingly, it was found that the quantum confinement effect is present (or absent) in the highest occupied (or lowest unoccupied) molecular orbital of the SiC quantum dots regardless of their surface terminations. Thus, the quantum confinement effect related to the energy gap observed experimentally (Phys. Rev. Lett., 2005, 94, 026102) is contributed to by the size-dependence of the highest occupied states; the absence of quantum confinement in the lowest unoccupied states is in contrary to the usual belief based on hydrogen-passivated C quantum dots. However, the cause of the absence of the quantum confinement in C nanodots is not transferable to SiC. We propose a model that provides a clear explanation for all findings on the basis of the nearest-neighbor and next-nearest-neighbor interactions between the valence atomic p-orbital in the frontier occupied/unoccupied states. We also found that the electron affinities of the SiC quantum dots, which closely depend on the surface environments, are negative for the C-H termination and positive for the Si-H termination. The prediction of negative electron affinities in SiC quantum dots by simple C-H termination indicates a promising application for these materials in electron-emitter devices. Our model predicts that GeC quantum dots with hydrogen passivation exhibit similar features to SiC quantum dots and our study confirms the crucial role that the surface environment plays in these nanoscale systems.

Electronic and magnetic properties of the two-dimensional C4H-type polymer with strain effects, intrinsic defects and foreign atom substitutions.

Following the two-dimensional periodic single-layer sheet successful synthesized experimentally very recently [Adv. Mater., 2011, 23, 4497], we present systematically the electronic and magnetic properties of this novel polymer (referred to as C(4)H) without and with strain-modifying, vacancy-doping, and nonmetal element (B, N, and P) doping by means of first-principles calculations. It was found that: (a) the C(4)H sheet is a nonmagnetic semiconductor with a wide indirect band gap. (b) The atomic structure, binding energies and electronic properties of the C(4)H sheet could be significantly modified by applying strain. (c) Vacancy defects can lead to intrinsic magnetism in C(4)H and, surprisingly, the induced spin polarization has large spatial extension; especially, room-temperature ferromagnetism in H vacancies-doped case is quite feasible. (d) Substitution of B, P and N at the unhydrogenated C site could form a local magnetic moment, whereas no spin-polarization could be induced for that with N at the hydrogenated C site. The present study provides theoretical insight leading to a better understanding of novel 2D structures, and further experimental studies are expected to confirm the attractive predictions.

[Comparison of changes in early pulmonary function and hemodynamic between unilateral and bilateral lung volume reduction for chronic obstructive pulmonary disease].

OBJECTIVE: To compare changes in early pulmonary function and hemodynamics between unilateral and bilateral lung volume reduction (LVRS) for severe chronic obstructive pulmonary disease (COPD). METHODS: Eighty-six patients with severe COPD underwent LVRS, 61 underwent unilateral LVRS and 25 underwent lateral LVRS. The results of lung function (FEV(1), RV, TLC), arterial blood gas analysis (PaO(2), PaCO(2)) and color Doppler echocardiography (CO, CI, EF, PAP) were evaluated preoperatively and 3, 6 months postoperatively. RESULTS: Six patients died. FEV(1), RV and TLC were improved significantly after (P < 0.05). PaO(2) increased (P < 0.05) and PaCO(2) decreased postoperatively (P < 0.05). According to the Doppler echocardiography there were no statistic difference in cardia functions (CO, CI, EF, PAP) between unilateral and bilateral LVRS preoperatively and 3, 6 months postoperatively. CONCLUSIONS: Unilateral and bilateral LVRS is safe and effective in the treatment of patients with severe COPD, the pulmonary function significantly improved postoperatively, but the results of bilateral LVRS is better than unilateral. Both unilateral and bilateral LVRS showed no significant deterioration in hemodynamics, there were no significant difference between preoperatively and postoperatively.

[Diagnosis and treatment for pulmonary thromboembolism in postthoracotomy patients].

OBJECTIVE: To report the experience in the diagnosis and treatment of pulmonary thromboembolism (PTE) in postthoracotomy patients and to analyze current problems in this field. METHODS: From January 2001 to June 2002 we diagnosed and treated 5 patient who had pulmonary thromboembolism, 72-168 hours after thoracotomy (male 4, female 1, mean age 63 years). Symptoms include breathholding, chest pain, palpitation, coma and so on. Physical signs include tachypnea, hypotension and tachycardia. We utilized spiral CT pulmonary artery angiography (SCTPA) and Doppler echocardiography to judge PTE. Pulmonary artery interventional therapy was used in 3 cases and total body thrombolysis in 1. RESULTS: 4 patients recovered with no complication and recurrence; 1 patient died from congestive heart failure and respiratory failure. CONCLUSION: Deep venous thrombosis (DVT) and PTE are related to the surgical intervention, chest tumor and thoracotomy is high risk factors. Screenage examination is primary to used. Pulmonary artery interventional therapy is safe to the postthoracotomy patients. Preventive measures is very important in the high-risk group.