Category: Statistics

Biomed Res Int. 2022 Feb 10;2022:2204745. doi: 10.1155/2022/2204745. eCollection 2022.

ABSTRACT

INTRODUCTION: The concept of selective neck dissection (SND) in locally advanced oral cancers is emerging. Contemporary studies support the feasibility of SND in selected node-positive oral cancers with early primaries. Nevertheless, the suitability of SND in clinically node-positive (cN+) oral cancers with advanced primaries (T3/T4) is unknown.

AIM: This study explores if patients with cN+ advanced primaries were suitable candidates for SND by spotting the involved lymph node distribution in various stations of the neck. Secondary objectives were to check if predictive clinicopathological factors for metastases to the neck in general also apply for lymph node metastases to levels IV and V.

METHODS: The present retrospective study analysed the distribution of pathologically involved lymph nodes in 134 patients and explored the interrelation of various predictive factors and cervical metastases overall and those specific to levels IV and V.

RESULTS: Level V was involved in 6.7% (6/83) of T4 and none of the T3 primaries. Depth of invasion (DOI), perineural invasion (PNI), and skin invasion were statistically significant predictors for nodal metastases in general on multivariate analysis.

CONCLUSION: Our analysis supports the option of considering SND, sparing level V in patients with cN+ oral cancers in a subset with T3 primary and nodal stage N2 and below.

PMID:35187160 | PMC:PMC8853780 | DOI:10.1155/2022/2204745

Biomed Res Int. 2022 Feb 9;2022:4946848. doi: 10.1155/2022/4946848. eCollection 2022.

ABSTRACT

BACKGROUND: Many complications occur after surgery in patients with spinal tuberculosis (STB); however, the severity varies in different patients. The complications’ severity is evaluated from grades I to V by the Clavien-Dindo classification (CDC), and grade V is the most severe. Most complications are mild, and only severe complications are life threatening, and thus, it is important to identify severe complications in patients with STB. The purpose of this study was to identify the risk factors of postoperative complication severity in patients with STB.

METHODS: Between January 2012 and May 2021, a retrospective study included 188 patients that underwent STB debridement surgery. The patients were divided into three groups based on postoperative complication severity. Clinical characteristics measured included age, sex, body mass index (BMI), comorbidities of diabetes mellitus and pulmonary tuberculosis, alcohol use and smoking history, course of disease, preoperative hemoglobin, preoperative serum albumin, preoperative lymphocytes, preoperative erythrocyte sedimentation rate (ESR), preoperative C-reactive protein (CRP), surgical approach, operating time, blood loss during surgery, postoperative hemoglobin, and postoperative serum albumin. The clinical characteristics of patients with STB who developed postoperative complications were evaluated using logistic regression analysis.

RESULTS: 188 patients suffered at least one postoperative complication; 77, 91, and 20 patients experienced grade I, II, and III-IV complications, respectively. In the univariate analysis, sex, diabetes mellitus, postoperative hemoglobin, and postoperative albumin are statistically significant. In the multivariable analysis, postoperative albumin (adjusted odds ratio (OR) = 0.861, P < 0.001) was an independent risk factor of the postoperative complication severity in patients with STB. Receiver operating characteristic (ROC) analysis showed that the optimal cutoff values for postoperative albumin were 32 g/L (sensitivity: 0.571, specificity: 0.714, area under the ROC curve: 0.680) and 30 g/L (sensitivity: 0.649, specificity: 0.800, area under the ROC curve: 0.697) for grade II and grade III-IV complications, respectively.

CONCLUSIONS: Postoperative albumin is an independent risk factor for postoperative complication severity in patients with STB. The improvement of postoperative albumin levels may reduce the risk of severe complications in patients with STB.

PMID:35187165 | PMC:PMC8850042 | DOI:10.1155/2022/4946848

Biomed Res Int. 2022 Feb 9;2022:1703869. doi: 10.1155/2022/1703869. eCollection 2022.

ABSTRACT

PURPOSE: To determine the hardness and Young’s moduli of both commercial and experimental vinyl poly siloxane (VPS).

METHODS: The purpose of this study was to develop a medium-bodied experimental (Exp-I, II, III, IV, and V) VPS impression materials and to analyse their effects on hardness and Young’s modulus and compare them with three commercial VPS materials (Aquasil, Elite, and Extrude) using Shore A hardness tester. Measurements were recorded after 1, 24, 72, and 168 hours of mixing. The results were analysed with one-way ANOVA and post hoc Tukey’s test using the SPSS PASW statistical 22 software.

RESULTS: Commercial and experimental vinyl polysiloxane exhibited higher Shore A hardness values with time (i.e., 1 hour after mixing, 24 hours after mixing, 72 hours after mixing, and 1 week after mixing). All Comml and Exp VPS demonstrated a significant increase (ANOVA, p < 0.05) in hardness at increasing time points. Generally, all commercial VPS exhibited significantly higher values for Shore A hardness compared to all Exp formulations. For commercial products, Elt M presented significantly highest values at all-time points followed by Aq M then Extr M. Exp-I was significantly harder than all other Exp VPS at all-time points. Young’s modulus values were directly related to Shore A hardness; materials with higher Shore A hardness values had higher Young’s moduli.

CONCLUSION: Continued polymerisation of elastomeric impression materials results in increased hardness over time. Hardness, Young’s moduli, and rigidity of the set commercial and experimental VPS materials were within the required limits. Shore A hardness and Young’s moduli were directly proportional to each other, and commercial and experimental materials had enough rigidity to contain the stone during pouring.

PMID:35187157 | PMC:PMC8849984 | DOI:10.1155/2022/1703869

Front Cardiovasc Med. 2022 Feb 3;9:817911. doi: 10.3389/fcvm.2022.817911. eCollection 2022.

ABSTRACT

BACKGROUNDS: Dynamic CT myocardial perfusion imaging (CT-MPI) allows absolute quantification of myocardial blood flow (MBF). Although appealing, CT-MPI has not yet been widely applied in clinical practice, partly due to our relatively limited knowledge of CT-MPI. Knowledge of distribution and variability of MBF in healthy subjects helps in recognition of physiological and pathological states of coronary artery disease (CAD).

OBJECTIVES: To describe the distribution and normal range of hyperemic MBF in healthy subjects obtained by dynamic CT-MPI and validate whether it can accurately identify functional myocardial ischemia when the cut-off value of hyperemia MBF is set to the lower limit of the normal range.

MATERIALS AND METHODS: Fifty-one healthy volunteers (age, 38 ± 12 years; 15 men) were prospectively recruited. Eighty patients (age, 58 ± 10 years; 55 men) with suspected or known CAD who underwent interventional coronary angiography (ICA) examinations were retrospectively recruited. Comprehensive CCTA + dynamic CT-MPI protocol was performed by the third – generation dual-source CT scanner. Invasive fractional flow reserve (FFR) measurements were performed in vessels with 30-90% diameter reduction. ICA/FFR was used as the reference standard for diagnosing functional ischemia. The normal range for the hyperemic MBF were defined as the mean ± 1.96 SD. The cut-off value of hyperemic MBF was set to the lower limit of the normal range.

RESULTS: The global hyperemic MBF were 164 ± 24 ml/100 ml/min and 123 ± 26 ml/100 ml/min for healthy participants and patients. The normal range of the hyperemic MBF was 116-211 ml/100 ml/min. Of vessels with an ICA/FFR result (n = 198), 67 (34%) were functionally significant. In the per-vessel analysis, an MBF cutoff value of <116 ml/100 ml/min can identify myocardial ischemia with a diagnostic accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of 85.9% (170/198), 91.0% (61/67), 83.2 % (109/131), 73.5% (61/83), and 94.8% (109/115). CT-MPI showed good consistency with ICA/FFR in diagnosing functional ischemia, with a Cohen’s kappa statistic of 0.7016 (95%CI, 0.6009 – 0.8023).

CONCLUSION: Recognizing hyperemic MBF in healthy subjects helps better understand myocardial ischemia in CAD patients.

PMID:35187130 | PMC:PMC8850642 | DOI:10.3389/fcvm.2022.817911

Front Cardiovasc Med. 2022 Feb 4;9:821938. doi: 10.3389/fcvm.2022.821938. eCollection 2022.

ABSTRACT

OBJECTIVE: To evaluate the efficiency of amiodarone in preventing the occurrence of reperfusion ventricular fibrillation (RVF) after aortic cross-clamp (ACC) release in patients undergoing open-heart surgery.

METHODS: We searched the Web of Science, Cochrane Library, EMBASE, and PubMed databases through January 2021 for relevant studies addressing the efficacy of amiodarone in preventing RVF after ACC release in patients undergoing cardiac surgery. A complete statistical analysis was performed using RevMan 5.3. Risk ratios (RRs) and 95% confidence intervals (CIs) were calculated to express the results of dichotomous outcomes using random or fixed-effect models. The chi-square test and I ² test were used to calculate heterogeneity.

RESULTS: Seven studies (856 enrolled patients; 311 in the amiodarone group, 268 in the lidocaine group, and 277 in the placebo group) were selected for the meta-analysis. The incidence of RVF was significantly decreased in the amiodarone group compared to the placebo group (RR = 0.69, 95%CI: 0.50-0.94, P = 0.02). However, amiodarone and lidocaine did not confer any significant difference (RR = 0.98, 95%CI: 0.61-1.59, P = 0.94). The percentage of patients requiring electric defibrillation counter shocks (DCSs) did not confer any significant difference between patients administered amiodarone and lidocaine or placebo (RR = 1.58, 95%CI: 0.29-8.74, P = 0.60; RR = 0.55, 95%CI: 0.27-1.10, P = 0.09; respectively).

CONCLUSIONS: Amiodarone is more effective than a placebo in preventing RVF after ACC release in cardiac surgery. However, the amiodarone group required the same number of electrical DCSs to terminate RVF as the lidocaine or placebo groups.

PMID:35187132 | PMC:PMC8854653 | DOI:10.3389/fcvm.2022.821938

Front Cardiovasc Med. 2022 Feb 4;9:775760. doi: 10.3389/fcvm.2022.775760. eCollection 2022.

ABSTRACT

BACKGROUND: Tranexamic acid (TXA) administered during off-pump coronary artery bypass (OPCAB) surgeries has achieved good blood control in small cohorts. We aimed to investigate the safety issues and hemostasis associated with TXA administration during OPCAB in a large retrospective cohort study.

METHODS: This study included 19,687 patients with OPCAB from 2009 to 2019. A total of 1,307 patients were excluded because they were younger than 18 years or certain values were missing. Among the remaining 18,380 patients, 10,969 were in the TXA group and 7,411 patients were in the no-TXA group. There were 4,889 patients whose TXA dose was ≥50 mg/kg, and the remaining 6,080 patients had a TXA dose of <50 mg/kg. Propensity score matching (PSM) was performed between the TXA and no-TXA groups and between the high-dose and low-dose groups, and statistical analysis was performed.

RESULTS: Tranexamic acid administration did not increase the risk of hospital death or thromboembolic events. Patients who administered TXA had less blood loss at 24 h (478.32 ± 276.41 vs. 641.28 ± 295.09, p < 0.001) and 48 h (730.59 ± 358.55 vs. 915.24 ± 390.13, p < 0.001) and total blood loss (989.00 ± 680.43 vs. 1,220.01 ± 720.68, p < 0.001) after OPCAB than the patients with non-TXA. Therefore, the risk of total blood exposure [odds ratio (OR) = 0.50, 95% CI 0.47-0.54, p < 0.001] or blood component exposure (p < 0.001) was decreased significantly in the patients who administered TXA. The TXA dosage did not impact the patient survival, thromboembolic events, or blood management.

CONCLUSIONS: The application of TXA was safe and provided blood control in patients with OPCAB, and the dosage did not affect these parameters.

PMID:35187119 | PMC:PMC8854353 | DOI:10.3389/fcvm.2022.775760

Front Cardiovasc Med. 2022 Feb 3;8:797976. doi: 10.3389/fcvm.2021.797976. eCollection 2021.

ABSTRACT

BACKGROUND: Ventricular premature complex (VPC) is one of the most common ventricular arrhythmias. The presence of VPC is associated with an increased risk of heart failure (HF).

METHOD: We designed a single-center, retrospective, and large population-based cohort to clarify the role of VPC burden in long-term prognosis in Taiwan. We analyzed the database from the National Cheng Kung University Hospital-Electronic Medical Record (NCKUH-EMR) and NCKUH-Holter (NCKUH-Holter). A total of 19,527 patients who underwent 24-h Holter ECG monitoring due to palpitation, syncope, and clinical suspicion of arrhythmias were enrolled in this study.

RESULTS: The clinical outcome of interests involved 5.65% noncardiovascular death and 1.53% cardiovascular-specific deaths between 2011 and 2018. Multivariate Cox regression analysis, Fine and Gray’s competing risk model, and propensity score matching demonstrated that both moderate (1,000-10,000/day) and high (>10,000/day) VPC burdens contributed to cardiovascular death in comparison with a low VPC burden (<1,000/day).

CONCLUSION: A higher VPC burden via Holter ECG is an independent risk factor of cardiovascular mortality.

PMID:35187109 | PMC:PMC8850345 | DOI:10.3389/fcvm.2021.797976

Front Cardiovasc Med. 2022 Feb 2;8:783358. doi: 10.3389/fcvm.2021.783358. eCollection 2021.

ABSTRACT

BACKGROUND: Percutaneous transluminal angioplasty (PTA) has been the conventional therapy to infrapopliteal arterial occlusion. Lately, cool excimer laser-assisted angioplasty has been proposed to be the alternate methods. We performed a systematic review and meta-analysis of prospective and retrospective cohort studies and randomized controlled trials to assess the effect of cool excimer laser-assisted angioplasty vs. tibial balloon angioplasty in patients with infrapopliteal arterial occlusion.

METHODS AND RESULTS: We systematically searched PubMed, Embase, Cochrane Central Register of Controlled Trials (CENTRAL) (all up to April, 2021). All prospective and retrospective cohort studies and randomized controlled trials comparing clinical outcomes between cool excimer laser-assisted angioplasty and tibial balloon angioplasty were included. The main endpoints were amputation-free survival (AFS), primary patency (6 months and 12 months) and free from target lesion revascularization (TLR) (3 years). Secondary outcomes included the major amputation (1 year), dissection, embolization and bailout stent. We chose the effect model according to studies’ heterogeneity. A total of 122 articles were found. According to inclusion criteria, 6 papers were finally selected for the detailed evaluation. Of the 6 papers, 4 were prospective cohort studies, and 2 were retrospective studies. Compared with PTA, CELA significantly increased the rate of patency (6 months: MD 13.01, 95% CI 3.12-22.90, P < 0.05; 12 months: MD 11.88 95% CI 8.38-15.37, P < 0.05) and the rate freedom from TLR (36 months: MD 7.51 95% CI 0.63-14.40, P < 0.05). There is no statistically difference of AFS, major amputation, dissection, embolization and bailout stent between CELA group and PTA group (MD -2.82, 95% CI -8.86-3.22, P = 0.36; MD -0.17, 95% CI -1.04-0.70, P = 0.39; MD 1.11, 95% CI 0.58-2.10, P = 0.75; MD 0.46, 95% CI 0.11-1.99, P = 0.30; MD 1.89, 95% CI 0.92-3.88, P = 0.09).

CONCLUSIONS: CELA had superior clinical (freedom from TLR) and angiographic outcomes (patency rate) for infrapopliteal arterial occlusion at the same time CELA does not have increased intervention-related complications compared to PTA. However, CELA is unable to improve the patient’s limb salvage rate compared with PTA.

PMID:35187104 | PMC:PMC8847249 | DOI:10.3389/fcvm.2021.783358

Front Cardiovasc Med. 2022 Feb 3;8:732122. doi: 10.3389/fcvm.2021.732122. eCollection 2021.

ABSTRACT

BACKGROUND: Insulin resistance (IR) plays a key role in the development of type 2 diabetes mellitus (T2DM) and is one of its most important characteristics. Previous studies have shown that IR and T2DM were independent risk factors for a variety of cardiovascular and cerebrovascular diseases. However, there are few studies on the relationship between IR and aortic dissection (AD). The goal of this research was to find evidence that IR promotes the occurrence of AD.

METHODS: Through the statistical analysis, we determined the proportion of glycosylated hemoglobin (HbA1c) abnormalities (HbA1c > 5.7) in people with acute thoracic aortic dissection (ATAD) and compared the difference of messenger RNA (mRNA) and protein expression of GluT1 in the thoracic aorta of normal people and those with ATAD to find evidence that IR is a causative factor in AD. The mouse model of IR and AD and the IR model of human aortic vascular smooth muscle cells (HA-VSMC) were established. Real time-PCR (RT-PCR) and Western blotting were used to study the mRNA and protein expression. Hematoxylin and eosin (H&E), Masson, and elastic fiber staining, and immunofluorescence were used to study the morphological structure.

RESULTS: The proportion of HbA1c abnormalities in patients with ATAD was 59.37%, and the mRNA and protein expression of GluT1 were significantly lower than that in normal people. Fasting glucose concentration (FGC), serum insulin concentration (SIC), and the homeostasis model assessment of insulin resistance (HOMA-IR) of mice was obviously increased in the high-fat diet group and the protein expressions of Glut1 and GluT4 were reduced, indicating that the mouse IR model was successfully established. The incidence of AD was different between the two groups (IR: 13/14, Ctrl: 6/14), and the protein expression of MMP2, MMP9, and OPN were upregulated and SM22 and α-SMA were downregulated in mice. The expressions of mRNA and protein of GluT1 and SM22 in HA-VSMCs with IR were reduced and OPN was increased.

CONCLUSION: Combined results of clinical findings, mouse models, and cell experiments show that IR induced the phenotypic switching of vascular smooth muscle cells (VSMCs) from contractile to synthetic, which contributes to the occurrence of AD. It provides a basis for further research on the specific mechanism of how IR results in AD and a new approach for the prevention and treatment of AD.

PMID:35187097 | PMC:PMC8850393 | DOI:10.3389/fcvm.2021.732122

Front Robot AI. 2022 Feb 3;8:667818. doi: 10.3389/frobt.2021.667818. eCollection 2021.

ABSTRACT

Collaborative robots (cobots) provide a wide range of opportunities to improve the ergonomics and efficiency of manual work stations. ISO/TS 15066 defines power and force limiting (PFL) as one of four safeguarding modes for these robots. PFL specifies biomechanical limits for hazardous impacts and pinching contacts that a cobot must not exceed to protect humans from serious injuries. Most of the limits in ISO/TS 15066 are preliminary, since they are based on unverified data from a literature survey. This article presents a human-subject study that provides new and experimentally verified limits for biomechanically safe interactions between humans and cobots. The new limits are specifically tailored to impact and pinching transferred through blunt and semi-sharp surfaces as they can occur in the event of human error or technical failures. Altogether 112 subjects participated in the study and were subjected to tests with emulated impact and pinching loads at 28 different body locations. During the experiments, the contact force was gradually increased until the load evoked a slightly painful feeling on the subject’s body location under test. The results confirm that the pain thresholds of males and females are different in specific body regions. Therefore, when defining biomechanical limits, the gender difference must be taken into account. A regression model was utilized to incorporate the gender effect as a covariate into a conventional statistical distribution model that can be used to calculate individual limits, precisely fitted to a specific percentile of a mixed group of male and female workers which interacting with cobots.

PMID:35187090 | PMC:PMC8850785 | DOI:10.3389/frobt.2021.667818