[Research Progress of SOA Formation from Anthropogenic VOCs Under Complex Pollution Condition].

Although the air quality in China has been greatly improved in recent years, the air pollution remains severe. The annual mean PM2.5 concentrations have not met the second grade of the National Ambient Air Quality Standards in China and are still much higher than the guideline value of the World Health Organization. Thus, the PM2.5 concentration needs to be further reduced. Secondary organic aerosol (SOA) is an important component of PM2.5 and has an important impact on air quality, global climate change, and human health. Therefore, understanding the formation mechanism of SOA is an important basis to control SOA and further reduce PM2.5. As an important precursor of SOA, volatile organic compounds (VOCs) can be oxidized by oxidants such as ·OH, NO3[KG-*2/3]·, Cl·, and O3 to generate low volatile organic compounds and further to form SOA through gas-particle partitioning, homogeneous nucleation, aqueous phase reaction, and heterogeneous reaction processes. The formation of SOA can be affected by many factors, such as the types and initial concentrations of VOCs, VOCs/NOx ratios, relative humidity (RH), temperature (T), seed aerosols, oxidants, aqueous phase process, and photochemical process. The observed SOA concentration is always underestimated by air quality models because a comprehensive understanding of the complexity of SOA chemical composition and formation mechanisms is still lacking, especially that under the highly complex air pollution conditions in China. Therefore, the formation mechanism and influencing factors of SOA under highly complex air pollution conditions have become an important concern in the field of atmospheric sciences. Recently, much laboratory work has focused on the formation of SOA under complex conditions. The research progress of SOA formation from different anthropogenic VOCs are reviewed here, and the methods used and the impact of different influencing factors on SOA formation are introduced. Finally, the key scientific issues that exist in the research of the SOA mechanism at present are put forward, and the future research direction is projected.

Perioperative risk factors associated with unplanned neurological intensive care unit readmission following elective supratentorial brain tumor resection.

OBJECTIVE: The aim of this study was to describe the clinical and procedural risk factors associated with the unplanned neurosurgical intensive care unit (NICU) readmission of patients after elective supratentorial brain tumor resection and serves as an exploratory analysis toward the development of a risk stratification tool that may be prospectively applied to this patient population. METHODS: This was a retrospective observational cohort study. The electronic medical records of patients admitted to an institutional NICU between September 2018 and November 2021 after elective supratentorial brain tumor resection were reviewed. Demographic and perioperative clinical factors were recorded. A prognostic model was derived from the data of 4892 patients recruited between September 2018 and May 2021 (development cohort). A nomogram was created to display these predictor variables and their corresponding points and risks of readmission. External validation was evaluated using a series of 1118 patients recruited between June 2021 and November 2021 (validation cohort). Finally, a decision curve analysis was performed to determine the clinical usefulness of the prognostic model. RESULTS: Of the 4892 patients in the development cohort, 220 (4.5%) had an unplanned NICU readmission. Older age, lesion type, Karnofsky Performance Status (KPS) < 70 at admission, longer duration of surgery, retention of endotracheal intubation on NICU entry, and longer NICU length of stay (LOS) after surgery were independently associated with an unplanned NICU readmission. A total of 1118 patients recruited between June 2021 and November 2021 were included for external validation, and the model's discrimination remained acceptable (C-statistic = 0.744, 95% CI 0.675-0.814). The decision curve analysis for the prognostic model in the development and validation cohorts showed that at a threshold probability between 0.05 and 0.8, the prognostic model showed a positive net benefit. CONCLUSIONS: A predictive model that included age, lesion type, KPS < 70 at admission, duration of surgery, retention of endotracheal intubation on NICU entry, and NICU LOS after surgery had an acceptable ability to identify elective supratentorial brain tumor resection patients at high risk for an unplanned NICU readmission. These risk factors and this prediction model may facilitate better resource allocation in the NICU and improve patient outcomes.

Perioperative Risk Factors Associated with Unplanned Neurological Intensive Care Unit Events Following Elective Infratentorial Brain Tumor Resection.

BACKGROUND: Our aim of this study was to identify risk factors and develop a prediction model for unplanned neurological intensive care unit (NICU) events after elective infratentorial brain tumor resection in order to propose an individualized admission to the NICU tailored to patient needs. METHODS: Patients admitted to our NICU between September 2018 and May 2021 after elective infratentorial brain tumor resection were reviewed. Prolonged NICU stays and unplanned NICU admissions were defined as unplanned NICU events. The prognostic model of unplanned NICU events was developed using a forward stepwise logistic regression analysis, and external validation was evaluated. The C-statistic was used to assess discrimination, and a smooth, nonparametric calibration line was used to assess calibration graphically in the model. RESULTS: Of the 1,710 patients in the development cohort, unplanned NICU events occurred in 162 (9.5%). Based on the lesion type, a Karnofsky Performance Status score <70 at admission, longer duration of surgery, bleeding in the operative area evident on postoperative computed tomography, higher fibrinogen and blood glucose levels at admission, and more intraoperative blood loss were independently associated with unplanned NICU events. The external validation test showed good discrimination (C-statistic = 0.811) and calibration (Hosmer-Lemeshow P = 0.141) for unplanned NICU events. CONCLUSIONS: Several patient and operative characteristics are associated with a greater likelihood of the occurrence of unplanned NICU events. In the future, we may be able to provide better help for the resource allocation of NICUs according to these risk factors and prediction models.

Clinical effect of minimally invasive duodenum preserving pancreatic head resection for benign and pre-malignant lesions of pancreatic head / 中华外科杂志

Objective: To examine the clinical effect of minimally invasive duodenum preserving pancreatic head resection(DPPHR) for benign and pre-malignant lesions of pancreatic head. Methods: The clinical data of patients with diagnosis of benign or pre-malignant pancreatic head tumor were retrospectively collected and analyzed,all of them underwent laparoscopic or robotic DPPHR between October 2015 and September 2021 at Division of Gastrointestinal and Pancreatic surgery,Zhejiang Provincial People's Hospital. Thirty-three patients were enrolled with 10 males and 23 females. The age(M(IQR)) was 54(32) years old(range: 11 to 77 years old) and the body mass index was 21.9(2.9)kg/m2(range: 18.1 to 30.1 kg/m2). The presenting symptoms included abdominal pain(n=12), Whipple triad(n=2), and asymptomatic(n=19). There were 7 patients with hypertension and 1 patient with diabetes mellitus. There were 19 patients who were diagnosed as American Society of Anesthesiologists class Ⅰ and 14 patients who were diagnosed as class Ⅱ. The student t test,U test, χ2 test or Fisher exact test was used to compare continuous data or categorized data,respectively. All the perioperative data and metabolic morbidity were analyzed and experiences on minimally invasive DPPHR were concluded. Results: Fourteen patients underwent laparoscopic DPPHR,while the rest of 19 patients received robotic DPPHR. Indocyanine green fluorescence imaging was used in 19 patients to guide operation. Five patients were performed pancreatico-gastrostomy and the rest 28 patients underwent pancreaticojejunostomy. Pathological outcomes confirmed 9 solid pseudo-papillary neoplasms, 9 intraductal papillary mucinous neoplasms, 7 serous cystic neoplasms, 6 pancreatic neuroendocrine tumors, 1 mucous cystic neoplasm, 1 chronic pancreatitis. The operative time was (309.4±50.3) minutes(range:180 to 420 minutes),and the blood loss was (97.9±48.3)ml(range:20 to 200 ml). Eighteen patients suffered from postoperative complications,including 3 patients experienced severe complications(Clavien-Dindo Grade ≥Ⅲ). Pancreatic fistula occurred in 16 patients,including 8 patients with biochemical leak,7 patients with grade B pancreatic fistula and 1 patient with grade C pancreatic fistula. No one suffered from the duodenal necrosis and none perioperative death was occurred. The length of hospital stay was 14(7) days (range:6 to 87 days). The follow-up was 22.6(24.5)months(range:2 to 74 months). None suffered from recurrence or metastasis. During the follow-up,all the patients were free of refractory cholangitis. Moreover,in the term of endocrine dysfunction,no postoperative new onset of diabetes mellitus were observed in the long-term follow-up. However,in the view of exocrine insufficiency,pancreatic exocrine insufficiency and non-alcoholic fatty liver disease (NAFLD) was complicated in 2 and 1 patient,respectively,with the supplement of pancreatic enzyme,steatorrhea and weight loss relieved,but NAFLD was awaited to be seen. Conclusions: Minimally invasive DPPHR is feasible and safe for benign or pre-malignant lesions of pancreatic head. Moreover,it is oncological equivalent to pancreaticoduodenectomy with preservation of metabolic function without refractory cholangitis.

Lateral or Medial Surgical Approaches for Thalamic Gliomas Resection?

OBJECTIVE: This study aimed to investigate the selection, safety, and prognosis of medial (transcorpus callosal) and lateral (translateral brain gyrus) approaches for adult thalamic glioma resection. METHODS: The medical records of adult patients with thalamic glioma between March 2006 and March 2016 in Huashan Hospital were reviewed. The probabilistic map of the gliomas was shown in Montreal Neurological Institute (MNI) space, and a paralleling midline was delineated to decide the approach. The extent of resection, complications, adjuvant treatment, and survival data were analyzed. A literature review was also conducted. RESULTS: Fifty-three patients with thalamic glioma were enrolled. Eighteen patients received tumor resection by a medial approach and 35 by a lateral approach. The probabilistic map based on 20 patients showed that 9 gliomas with ≥45% located in the medial side were treated medially and the other 11 gliomas were treated laterally. Both approaches achieved adequate extent of resection with similar morbidity. Kaplan-Meier analysis showed no significant difference of overall survival by a transcorpus callosal or translateral brain gyrus approach. Total resection (TR) or subtotal resection (STR) (P = 0.0003), radiochemotherapy (P < 0.0001), and low-grade glioma (P = 0.031) were correlated with better OS. Multivariate Cox regression analysis showed that TR/STR (P = 0.007; 95% confidence interval, 1.345-6.287) and radiochemotherapy (P < 0.0001; 95% confidence interval, 4.740-71.569) were independent prognostic factors for adult thalamic gliomas. CONCLUSIONS: Both medial and lateral approaches are feasible and adequate for resection of thalamic gliomas. The paramidline paralleling midline crossing the genu of the internal capsule could help make the choice. TR/STR, radiochemotherapy, and low-grade glioma could benefit the prognosis.

[Diurnal Variation of SOA Formation Potential from Ambient Air at an Urban Site in Beijing].

Secondary organic aerosol (SOA) is an important component of atmospheric fine particles (PM2.5). The study of the diurnal variation of SOA formation potential is important for understanding the evolution of SOA and its contribution to fine particle pollution. The oxidation flow reactor (OFR) was used to study the SOA formation potential of ambient air in summer at an urban site in Beijing. The high concentration of OH radicals in the reactor can oxidize the volatile organic compounds (VOCs) and lead to SOA formation. The hour average SOA formation potential varied between 3.9-9.4 µg·m-3 in a day and had a higher value at night than in the daytime. The lowest value of SOA formation potential was about 3.9 µg·m-3 observed at 16:00 in the afternoon. This variation of SOA formation potential is consistent with the typical VOCs, such as toluene, and inversely related to the concentration of ozone. In addition to the impact of change in the height of the boundary layer, experimental data showed that the reduction of VOCs in photo-oxidation in the daytime was an important reason for the decrease of SOA formation potential in daytime. Compared to similar studies in developed countries, the SOA formation potential was higher in Beijing due to the higher concentrations of VOCs and might make an important contribution to the fine particle pollution in Beijing.

A study on the anatomy of the transcorpus callosal ventricle approach to the thalamic region using the mi- croscope and neuroendoscope / 中国神经精神疾病杂志

Objective To investigate the anatomic landmarks during the exposure of thalamus via the transcorpus callosal ventricle approach between microscope and endoscope to provide an anatomic foundation for clinical application. Methods The transcorpus callosal ventricle approach to expose the thalamus was simulated in selected 6 (12 sides) red and blue latex-perfused cadaver head specimens. The anatomic structures of four stages-interhemispheric, septum pellu?cidum cavity, lateral ventricle and third ventricle were examined by microscope and endoscope and relevant anatomic date was obtained during the process. Results Both microscope and endoscope could show the anatomic structures clear?ly during the interhemispheric and septum pellucidum cavity stages. The major landmarks of the interhemispheric cavity included callosal margin artery, cingulate sulcus, pericallosal artery and corpus callosum, and landmarks of septum pellu?cidum cavity included the septum pellucidum and body of fornix. Lateral ventricle stage-the major landmarks contained foramen of monro, septum vein, thalamus striatum vein, choroid plexus, body of fornix and body of caudate nucleus. The blind field under microscope such as anterior part of frontal horn (25.7mm±1.7mm vs. 14.2mm±1.2mm, P<0.05), lateral part (1/3) (12.1mm ± 0.7mm vs. 7.0mm ± 0.9mm, P<0.05) and posterior part (2/5) (28.8mm ± 1.4mm vs. 18.7mm ± 1.4mm, P<0.05) of thalamus could be made up by endoscope. Third ventricle stage-neither microscope nor endoscope could show the medial part of thalamus effectively due to the restriction of fornix and internal cerebral vein. Conclusions The anatomic landmarks can be identified during the exposure of thalamus via the transcorpus callosal ventricle approach. The coordination of microscope and endoscope can be helpful to identify eloquent structures and make up blind surgical field.

[A study of efficiacy of infliximab treatment for Crohn's disease.].

OBJECTIVE: To investigated the potential and safety of the monoclonal antibody to TNFalpha infliximab (IFX) in the treatment of active Crohn's disease (CD). METHODS: Patients who were confirmed diagnosis of CD and were unresponsive to the conventional treatments, or recurred after surgeries, or discontinued treatment due to drug intolerance, were treated with IFX intravenously in a dose of 5 mg/kg at week 0, 2, 6 (IFX infusion continued at an interval of every 8 weeks if respond to initial dosing). Clinical assessments, including disease activity, blood biological markers and colonoscopic findings, were performed at baseline (week 0) and each week (4 weeks or later for colonoscopy) after IFX infusion were conducted until the week before 4(th) infusion from initiated. RESULTS: Ten patients (8 male, 2 female) with mean age of 31.4 years (ranged from 15 to 65 years old) were included in the analysis. The mean subjective score from baseline to week 14 was decreased from 2.2 +/- 0.6 to 1.2 +/- 0.4 (P < 0.05). The mean Harvey-Bradshaw index was 6.6 +/- 1.6 at baseline and 2.1 +/- 1.0 at week 14. The levels of ESR, CRP, serum total protein (TP) and albumin (Alb) were significantly improved during the 14-week period. Colonoscopy showed a remarkable improvement of Crohn's Disease Endoscopic Index of Severity (CDEIS). No infusion-related reaction was observed in all patients during the treatment. Mild or transient skin itching and headache were respectively reported in two patients. Transient elevation of serum ALT and AST after 3(rd) infusion in one patient, and severe anemia including leucopenia and thrombocytopenia at week 35 after 1(st) infusion in one male patient were observed. CONCLUSIONS: Treatment with three infusions of IFX in a dose of 5 mg/kg was effective for induction of remission for active and complex CD patients who failed to respond to conventional treatment. Long-term safety of the therapy effect was warranted in further investigations.