Objective To observe the effects of positive end-expiratory pressure(PEEP) on oxygen utiliza-tion coefficient in patients with acute respiratory distress syndrome(ARDS). Methods 28 ARDS patients with me-chanical ventilation were studied. Catheter of central vein was laid. Increment levels of PEEP(0,5, 10, 15 and 20cmH2O) were applied sequentially. Hemodynamics and oxygen metabolism parameters were measured and calcula-tion of O2 UC [O2 UC = (SaO2 -SvO2.)/SaO2] were carried out respectively. O2 UC in 30 normal subject groups were carried out. Results Arterial oxygen tension(PaO2) increased significantly(P < 0.05) at PEEP 5cmH2O. Oxygen u-tilization coefficient (O2 UC), heart rate(HR) and mean blood pressure (MBP) were not significantly different (P >0.05) at PEEP 10cmH2O. At PEEP 15cmH2 O, O2UC and HR increased significantly (P < 0.05), but M BP reduced obviously(P < 0.05). Conclusions Too high PEEP can result in oxygen utilization coefficient of ARDS patient de-acend furthur, can not really correct oxygen difieiency condition in patients' organization cell. The optimal PEEP should be found, and blood capacity should be appropriately increased.

10.3969/j.issn.1007-3969.2013.05.009

Background and purpose:Primary malignant melanomas of the uterine cervix and vagina are rare neoplasms with very poor prognosis. This article aimed at investigating the clinicopathologic characteristics, treatment and prognosis of primary malignant melanomas of the cervix and vagina. Methods:The clinical data of 51 patients with primary malignant melanomas of the cervix and vagina treated at Fudan University Shanghai Cancer Center from Dec.1998 to Jul. 2011 were reviewed. Results:The 2-and 4-year progression-free survival (PFS) rates were 32.8%and 13.1%, respectively. The 2-and 4-year overall survival (OS) rates were 67.2%and 39.8%, respectively. Three patients survived more than 5 years. Twenty-nine (56.9%) patients had a recurrence. The common sites were vaginal stump/pelvis (10 patients, 34.5%), liver (4 patients, 13.9%), lung (3 patients, 10.3%), bone (3 patients, 10.3%) and vulva (3 patients, 10.3%). Larger tumor size and lymphovascular space invasion were the independent predictors of poor OS (P<0.05). Pelvic lymph nodes metastases were associated with shorter PFS (P=0.05). Among them, those who received combined immunotherapy and chemoradiotherapy achieved longer median time to progression (TTP) (17 months) compared with patients who had chemotherapy alone (9 months) or immunotherapy alone (11 months). Conclusion:Primary melanomas of cervix and vagina have a very poor prognosis. The multidisciplinary treatment of combining surgery, chemoradiotherapy, and immunotherapy can improve the patients’ prognosis.

Background and purpose: Ovarian lymphoma (OL) is usually misdiagnosed as ovarian cancer with bulk lymph node invasion (OC-BLN), and vice versa. Therefore, to distinguish these two types of disease, we compared their clinical characteristics in this study. Methods: This study retrospectively reviewed 14 OL and 14 OC-BLN patients from Fudan University Shanghai Cancer Center and Shanghai Eighth People's Hospital. The clinical char-acteristics, image and laboratory examination data were compared. Results: There was no significant difference in age, symptom, fever, weight loss and volume of ascitic fluid between the two groups. Comparing with OC-BLN, OL patients have larger tumor in ovaries [(13.04±5.94) cm vs (7.78±6.38) cm, P=0.033], and higher percentage of solid ovarian tumor (85.71% vs 28.5%, P=0.006). Lactate dehydrogenase(LDH)/CA125 was higher in OL (7.66±8.03) than OC-BLN (0.31±0.27, P=0.009). Using LDH/CA125 to diagnose OL, area under the curve (AUC) was 0.952. When the threshold value was set at 1, the sensitivity and specificity was 91.7% and 100%, respectively. Conclusion: OL and OC-BLN are easily to be misdiagnosed. OL has larger and more solid tumor than OC-BLN. LDH/CA125 can help to distinguish these two diseases and guide clinical decision making.

Objective: To investigate the potential mechanism of Wendan decoction in obesity by screening target genes with promoter region methylation changes and constructing a multiple signaling pathways network based on promoter methylation. Methods: The methylation degree of Itgad, Col8a1, Adra2b, Jund, Rab2a, Wnt8b, Fzd9, B4galt7, Pik3cd, Creb1, Stard8, and Mmp1 in the abdominal adipose tissue of obese rats was determined using the Agena MassARRAY system. Western blot was performed to assess protein expression levels. Target genes were identified based on the methylation degree in the promoter region and protein expression. Enrichment analysis of signaling pathways was conducted to identify relevant target genes and obtain a multiple signaling pathway network associated with obesity. Core and terminal effector molecules in the pathway networks were selected as research targets for reverse transcription-polymerase chain reaction (RT-PCR) analysis. Results: Four genes (Adra2b, Creb1, Itgad, and Pik3cd) showed a degree of promoter methylation consistent with their respective protein expression levels. Among them, Adra2b, Creb1, and Pik3cd expression increased, while that of Itgad decreased. Enrichment analysis revealed that Creb1 and Pik3cd were involved in 6 signaling pathways related to obesity: tumor necrosis factor (TNF) signaling pathway, growth hormone synthesis/secretion and action, adenosine 5′-monophosphate-activated protein kinase (AMPK) signaling pathway, relaxin signaling pathway, cyclic nucleotide (cAMP) signaling pathway, and phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) signaling pathway. Subsequently, a multiple signaling pathways network was constructed based on promoter methylation. Key molecules including protein kinase B (AKT), mechanistic target of rapamycin complex 1 (mTORC1), and unc-51 like autophagy activating kinase 1 (ULK1), as well as terminal effector molecules interleukin-1β (IL-1β), interleukin-6 (IL-6), and chemokine (C-X-C motif) ligand 2 (CXCL2) were selected as research targets. Wendan decoction decreased the expressions of AKT, mTORC1, IL-1β, IL-6, and CXCL2 while up-regulating ULK1 expression. Conclusion The mechanism of Wendan decoction in preventing obesity involves the regulation of multiple signaling pathways through the control of Creb1 and Pik3cd gene promoter methylation. However, the associated multi-path gene regulation mechanism in preventing obesity is complex. Thus, further exploration is needed to elucidate the role of methylation changes in this mechanism.

Objective:To explore the effect of hydrogen sulfide (H 2S) on modulating the subunit Kir6.2 of adenosine triphosphate sensitive potassium channels via the cyclic guanosine monophosphate-dependent protein kinase (cGMP/PKG) signaling pathway in epileptic rat models. Methods:Sixty adult male SD rats were randomly divided into the following six groups (10 rats in each group) by random number table method: control, epileptic, H 2S donor, H 2S donor+epileptic, KT5823 (one inhibitor of the cyclic guanosine monophosphate-dependent protein kinase)+H 2S donor+epileptic, and glibenclamide (one inhibitor of the adenosine triphosphate sensitive potassium channels)+H 2S donor+epileptic groups. Except the control group, SD rats were intraperitoneally injected with plentylenetetrazole to make the kindling models and their behaviours were recorded including the latency period, the grade, and the duration of the first epileptic seizure according to the Racine′s standard. The waveforms of electroencephalogram (EEG) in hippocampus were also recorded during the seizure. The mRNA and protein levels of PKG and Kir6.2 in hippocampus were evaluated by Western blotting and quantitative real-time polymerase chain reaction, and the hippocampal concentrations of cGMP and phosphorylation of cyclic guanosine monophosphate-dependent protein kinase (p-PKG) were detected by enzyme linked immunosorbent assay. Results:Rats in the epileptic group showed Ⅳ-Ⅴ grade of epileptic seizure [4.500 (4.000, 4.875)], short latency period [(10.37±8.21) min] but long duration [(69.50±24.37) s] of seizure. Compared to the epileptic group, rats in the H 2S donor group showed Ⅱ-Ⅲ grade of epileptic seizure ( P=0.004), significantly longer latency period ( P<0.001), and shorter duration of seizure ( P<0.001). Compared to the H 2S donor+epileptic group, rats in the KT5823+H 2S donor+epileptic group showed Ⅲ-Ⅳ grade of epileptic seizures, significantly shorter latency period ( P<0.001), and longer duration of seizure ( P<0.001). The results of EEG showed that the wave patterns in the epileptic group were spike or sharp waves and the amplitudes were largest [(190.570±23.590) μV]. Compared with the epileptic group, amplitudes were reduced ( P<0.001) in the H 2S donor+epileptic group. PKG mRNA and PKG protein were expressed differently among all groups (PKG mRNA: n=5, H=26.714, P<0.001; PKG protein: n=5, F=30.597, P<0.001). Compared with the control group, the expression of both PKG mRNA and PKG protein was decreased (PKG mRNA: 1.000±0.001 vs 0.782±0.064, P=0.023; PKG protein: 0.550±0.037 vs 0.145±0.020, P=0.042) in the epileptic group. Besides, Kir6.2 mRNA and Kir6.2 protein were expressed differently among all groups (Kir6.2 mRNA: n=5, H=27.761, P<0.001; Kir6.2 protein: n=5, F=60.659, P<0.001). Compared with the control group, the expression of both Kir6.2 mRNA and Kir6.2 protein was decreased (Kir6.2 mRNA: 1.000±0.001 vs 0.897±0.033, P=0.004; Kir6.2 protein: 0.384±0.035 vs 0.215±0.016, P=0.024) in the epileptic group. And the concentrations of cGMP and p-PKG were decreased (cGMP: P<0.001; p-PKG: P<0.001) in the epileptic group. The results in the H 2S donor+epileptic group were up-regulated (PKG mRNA: P=0.047; PKG protein: P<0.001; Kir6.2 mRNA: P=0.011; Kir6.2 protein: P<0.001; cGMP: P<0.001; p-PKG: P<0.001) compared with the epileptic group. However, the results in the KT5823+H 2S donor+epileptic group were down-regulated (PKG mRNA: P=0.015; PKG protein: P=0.027; Kir6.2 mRNA: P=0.013; Kir6.2 protein: P=0.017; cGMP: P=0.005; p-PKG: P<0.001) compared with the H 2S donor+epileptic group. Conclusion:A possible mechanism is that H 2S prevents the epileptic seizure from modulating the subunit Kir6.2 of ATP sensitive potassium channels via the cGMP/PKG signaling pathway.

Purpose: This study aimed to evaluate nursing students’ understanding of the prevention of COVID-19, as well as their anxiety towards the disease and their perception of their professional identity in the wake of the pandemic, in Zhengzhou, China. Methods: A cross-sectional study was designed to investigate 474 nursing students by cluster sampling using a stratified questionnaire from February 15 to March 31, 2020. Multiple linear regression was used to identify the factors affecting professional identity. Binary and multiple logistic regression were used to identify the factors affecting anxiety. Results: Responders with a high level of understanding of COVID-19 and frequent use of behavioral strategies for its prevention comprised 93.2% and 30.0% of the cohort, respectively. Professional identity was significantly associated with gender and anxiety (p < .050). The prevalence of anxiety among nursing students was 12.4%. Male (odds ratio [OR] = 2.39; 95% confidence interval [CI] = 1.26~4.52), sophomores (OR = 5.30; 95% CI = 1.61~7.45), and infrequent use of prevention measures (OR = 3.49; 95% CI = 1.16~5.19) had a significant effect on anxiety. Conclusion Anxiety during the COVID-19 epidemic gives an adverse effect on the professional identity of nursing in students. Nursing education institutions need to provide psychological counseling services for nursing students, in addition to improving their teaching of COVID-19 prevention strategies.

Objective To prepare the rat model of type 2 diabetes mellitus (T2DM), and to ob-serve the characteristics of peripheral neuropathy. Methods High fat and high sugar diets were fed for 8 weeks to induce insulin resistance and then low dose streptozotocin ( STZ) was injected intraperitoneally to induce type 2 diabetes mellitus models in Sprague Dawley rats. Blood glucose and serum insulin levels con-tinuous were monitored. Tactile allodynia in response to von Frey ( VF) filament stimulation of the plantar hind paws and paw withdrawal thermal latency ( PWTL) to plantar test were used as the criterion for diabetic neuropathy. Instruments AD was used to detect nerve conduction velocity ( NCV) of sciatic nerve in rat and the morphological and pathological changes of sciatic nerve were detected by electron microscope. Results The characteristics of T2DM rats by peripheral neuropathy in this method were that 50％ force withdrawal threshold and PWTL were measured. Both values of diabetic rats were decreased from the day of STZ injec-tion until 4 weeks after STZ injection, and then increased 8 weeks after STZ injection (50％ force withdraw-al threshold values, (11.8 ±0.8)g, (8.4 ±0.7)g and (16.2 ±1.4)g; PWTL (10.2 ±0.9)s, (8.3 ± 1. 2)s and (13. 2 ± 1. 0)s. These results indicated that tactile sensation changed from hypersensitive to hy-posensitive. Compared to the NC group, the sciatic nerve motor and sensory conduction velocity were signifi-cantly decreased at 4 and 8 weeks in DM group, respectively. Compared to DM group at 4 weeks, the sciat-ic nerve motor and sensory conduction velocities were further decreased in the DM group at 8 weeks. Con-clusively, sciatic nerve showed obvious demyelination and axonal collapse. Conclusions T2DM rat model was successfully induced by high fat and sugar diet combined with small dose of STZ injection. The rat mod-el has typical pathological change of peripheral nerve. It might provide a particularly advantageous tool for investigations of diabetes and its chronic complications.

COVID-19/prevention & control* ; Communicable Disease Control ; General Surgery/organization & administration* ; Guidelines as Topic ; Health Care Rationing ; Health Services Needs and Demand ; Health Workforce ; Humans ; Practice Guidelines as Topic ; SARS-CoV-2 ; Singapore/epidemiology* ; Surgical Procedures, Operative ; Triage

Objective:To investigate the influencing factors of recurrence after radical resection of middle and low rectal cancer, and to establish a prediction model based on magnetic resonance imaging (MRI) measurement of perirectal fat content and investigate its application value.Methods:The retrospective cohort study was constructed. The clinicopathological data of 254 patients with middle and low rectal cancer who were admitted to Tianjin Union Medical Center from December 2016 to December 2021 were collected. There were 188 males and 66 females, aged (61±9)years. All patients underwent radical resection of rectal cancer and routine pelvic MRI examina-tion. Observation indicators: (1) follow-up and quantitative measurement of perirectal fat content; (2) factors influencing tumor recurrence after radical resection of middle and low rectal cancer; (3) construction and evaluation of the nomogram prediction model of tumor recurrence after radical resection of middle and low rectal cancer. Measurement data with normal distribution were represented as Mean± SD, and measurement data with skewed distribution were represented as M(rang) and M( Q1, Q2). Count data were described as absolute numbers. Univariate and multivariate analyses were conducted using the COX regression model. The rms software package (4.1.3 version) was used to construct the nomogram and calibration curve. The survival software package (4.1.3 version) was used to calculate the C-index. The ggDCA software package (4.1.3 version) was used for decision curve analysis. Results:(1) Follow-up and quantitative measurement of perirectal fat content. All 254 patients were followed up for 41.0(range, 1.0?59.0)months after surgery. During the follow-up period, there were 81 patients undergoing tumor recurrence with the time to tumor recurrence as 15.0(range, 1.0?43.0)months, and there were 173 patients without tumor recurrence. The preoperative rectal mesangial fascia envelope volume, preoperative rectal mesangial fat area, preoperative rectal posterior mesangial thickness were 159.1(68.6,266.5)cm3, 17.0(5.1,34.4)cm2, 1.2(0.4,3.2)cm in the 81 patients with tumor recurrence, and 178.5(100.1,310.1)cm3, 19.8(5.3,40.2)cm2 and 1.6(0.3,3.7)cm in the 173 patients without tumor recurrence. (2) Factors influencing tumor recurrence after radical resection of middle and low rectal cancer. Results of multivariate analysis showed that poorly differentiated tumor, tumor pathological N staging as N1?N2 stage, rectal posterior mesangial thickness ≤1.43 cm, magnetic resonance extra mural vascular invasion, tumor invasion surrounding structures were independent risk factors of tumor recurrence after radical resection of middle and low rectal cancer ( hazard ratio=1.64, 2.20, 3.19, 1.69, 4.20, 95% confidence interval as 1.03?2.61, 1.29?3.74, 1.78?5.71, 1.02?2.81, 2.05?8.63, P<0.05). (3) Construction and evaluation of the nomogram prediction model of tumor recurrence after radical resection of middle and low rectal cancer. Based on the results of multivariate analysis, the tumor differentiation, tumor pathological N staging, rectal posterior mesangial thickness, magnetic resonance extra mural vascular invasion, tumor invasion surrounding structures were included to construct the nomogram predic-tion model of tumor recurrence after radical resection of middle and low rectal cancer. The total score of these index in the nomogram prediction model corresponded to the probability of post-operative tumor recurrence. The C-index of the nomogram was 0.80, indicating that the prediction model with good prediction accuracy. Results of calibration curve showed that the nomogram prediction model with good prediction ability. Results of decision curve showed that the prediction probability threshold range was wide when the nomogram prediction model had obvious net benefit rate, and the model had good clinical practicability. Conclusions:Poorly differentiated tumor, tumor pathological N staging as N1?N2 stage, rectal posterior mesangial thickness ≤1.43 cm, magnetic resonance extra mural vascular invasion, tumor invasion surrounding structures are independent risk factors of tumor recurrence after radical resection of middle and low rectal cancer. Nomogram prediction model based on MRI measurement of perirectal fat content can effectively predict the probability of postoperative tumor recurrence.