Final epidemic size of a two-community SIR model with asymmetric coupling.

Communities are commonly not isolated but interact asymmetrically with each other, allowing the propagation of infectious diseases within the same community and between different communities. To reveal the impact of asymmetrical interactions and contact heterogeneity on disease transmission, we formulate a two-community SIR epidemic model, in which each community has its contact structure while communication between communities occurs through temporary commuters. We derive an explicit formula for the basic reproduction number R 0 , give an implicit equation for the final epidemic size z, and analyze the relationship between them. Unlike the typical positive correlation between R 0 and z in the classic SIR model, we find a negatively correlated relationship between counterparts of our model deviating from homogeneous populations. Moreover, we investigate the impact of asymmetric coupling mechanisms on R 0 . The results suggest that, in scenarios with restricted movement of susceptible individuals within a community, R 0 does not follow a simple monotonous relationship, indicating that an unbending decrease in the movement of susceptible individuals may increase R 0 . We further demonstrate that network contacts within communities have a greater effect on R 0 than casual contacts between communities. Finally, we develop an epidemic model without restriction on the movement of susceptible individuals, and the numerical simulations suggest that the increase in human flow between communities leads to a larger R 0 .

Detection of epistasis interaction loci for fiber quality-related trait via 3VmrMLM in upland cotton.

Cotton fiber quality-related traits, such as fiber length, fiber strength, and fiber elongation, are affected by complex mechanisms controlled by multiple genes. Determining the QTN-by-QTN interactions (QQIs) associated with fiber quality-related traits is therefore essential for accelerating the genetic enhancement of cotton breeding. In this study, a natural population of 1,245 upland cotton varieties with 1,122,352 SNPs was used for detecting the main-effect QTNs and QQIs using the 3V multi-locus random-SNP-effect mixed linear model (3VmrMLM) method. A total of 171 significant main-effect QTNs and 42 QQIs were detected, of which 22 were both main-effect QTNs and QQIs. Of the detected 42 QQIs, a total of 13 significant loci and 5 candidate genes were reported in previous studies. Among the three interaction types, the AD interaction type has a preference for the trait of FE. Additionally, the QQIs have a substantial impact on the enhancement predictability for fiber quality-related traits. The study of QQIs is crucial for elucidating the genetic mechanism of cotton fiber quality and enhancing breeding efficiency.

Development of an Independent Prognostic Signature Based on Three Hypoxia-Related Genes for Breast Cancer.

Background: Hypoxia was considered to be a prognostic indicator in a variety of solid tumors. This study aims at identifying the hypoxia-related genes (HRGs) in breast cancer (BC) and the feasibility of HRGs as a prognostic indicator. Methods: We downloaded the mRNA expression data of BC patients from TCGA and GEO databases. The LASSO Cox regression analysis was applied to screen the hub HRGs to establish a prognostic Risk Score. The independence of Risk Score was assessed by multivariate Cox regression analysis. And the immune checkpoint analysis was also performed. In addition, we also detected the expression level of hub HRGs in MCF-10A cells, MCF-7 cells, and SK-BR-3 cells by RT-qPCR. Results: Three HRGs were identified as hub genes with prognostic value in BC, including CA9, PGK1, and SDC1. The Risk Score constructed by these three genes could efficiently distinguish the prognosis of different BC patients and has been shown to be an independent prognostic indicator. In the high-risk group, patients had lower overall survival and poorer prognosis. In addition, the expression levels of five immune checkpoints (PD1, CTLA4, TIGIT, LAG3, and TIM3) in the high-risk group were significantly higher than those in the low-risk group. Moreover, the expression levels of PGK1 and SDC1 in BC cells were significantly increased. Conclusion: In this study, we established an efficiently model based on three optimal HRGs (CA9, PGK1, and SDC1) could clearly distinguish the prognosis of different BC patients.

Knockdown of miR-372-3p Inhibits the Development of Diabetic Cardiomyopathy by Accelerating Angiogenesis via Activating the PI3K/AKT/mTOR/HIF-1α Signaling Pathway and Suppressing Oxidative Stress.

Background: DCM is the most common and malignant complication of diabetes. It is characterized by myocardial dilatation, hypertrophy, fibrosis, ventricular remodeling, and contractile dysfunction. Although many studies have demonstrated the function of miRNAs in the progression of DCM, but the specific role of miR-372-3p in DCM remains unknown. Methods: C57/BL6J mice were used to construct mouse models of DCM by intraperitoneal injection of STZ (50 mg/kg/d) for 5 consecutive days. Then the mice were randomly divided into model group (intramyocardial injection of empty lentivirus) and miR-372-3p KD group (intramyocardial injection of miR-372-3p KD lentivirus at 109/mouse). Besides, the control group (injection of 0.9% normal saline) was also set up. LY294002, a PI3K inhibitor, was employed in the current study. Western blotting, immunofluorescence staining, quantitative ultrasound method, Masson's trichrome staining, and bioinformatics analysis were performed. Results: It was found that miR-372-3p KD significantly improved left ventricular dysfunction and cardiac hypertrophy in DCM mice. Furthermore, it also improved myocardial interstitial fibrosis and remodeling in DCM mice. Immunofluorescence staining and RT-qPCR revealed that miR-372-3p KD might accelerate cardiac remodeling by increasing angiogenesis in DCM mice. Western blotting results revealed that miR-372-3p was an upstream target of the PI3K/AKT-mTOR and HIF-1α signals, as well as NOX2, NOX4, which were responsible for angiogenesis in DCM mice. Besides, the in vitro experiment showed that LY294002 markedly diminished the increased expression levels of p-PI3K, AKT, p-mTOR, p-P70S6K, HIF-1α, NOX2, and NOX4 in the model group and the miR-372-3p KD group, suggesting that PI3K signaling pathway and oxidative stress are involved in miR-372-3p KD-induced angiogenesis in HG-stimulated C166 cells. Conclusions: MiR-372-3p KD inhibits the development of DCM via activating the PI3K/AKT/mTOR/HIF-1α signaling pathway or suppressing oxidative stress. This offers an applicable biomarker for DCM treatment.

Association Between Maternal Weight Gain in Different Periods of Pregnancy and the Risk of Venous Thromboembolism: A Retrospective Case-Control Study.

Background: Venous thromboembolism (VTE) remains an important cause of maternal deaths. Little is known about the associations of specific periods of gestational weight gain (GWG) with the category of VTE, pulmonary embolism (PE), or deep venous thrombosis (DVT) with or without PE. Methods: In a retrospective case-control study conducted in Shanghai First Maternity and Infant Hospital from January 1, 2017 to September 30, 2021, cases of VTE within pregnancy or the first 6 postnatal weeks were identified. Controls without VTE were randomly selected from women giving birth on the same day as the cases, with 10 controls matched to each case. Total GWG and rates of early, mid, and late GWG values were standardized into z-scores, stratified by pre-pregnant body mass index (BMI). The adjusted odds ratios (aORs) and 95% confidence intervals (CIs) were estimated through multivariate logistic regression models. Results: There were 196 cases (14.4 per 10,000) of VTE within pregnancy or the first 6 postnatal weeks were identified. Higher total weight gain was associated with increased risks of PE (aOR, 13.22; 95% CI, 2.03-85.99) and VTE (OR, 10.49; 95% CI, 1.82-60.45) among women with underweight. In addition, higher total weight gain was associated with increased risk of PE (aOR, 2.06; 95% CI, 1.14-3.72) among women with healthy weight. Similarly, rate of higher early weight gain was associated with significantly increased risk for PE (aOR, 2.15; 95% CI, 1.05-4.42) among women with healthy BMI. The lower rate of late weight gain was associated with increased risks of PE (aOR, 7.30; 95% CI, 1.14-46.55) and VTE (OR, 7.54; 95% CI, 1.20-47.57) among women with underweight. No significant associations between maternal rate of mid GWG and increased risk for any category of VTE, PE, or DVT with or without PE were present, regardless of maternal pre-pregnant BMI. Conclusion: The GWG associations with the category of VTE, PE, or DVT with or without PE differ at different periods of pregnancy. In order to effectively improve maternal and child outcomes, intensive weight management that continues through pregnancy may be indispensable.

Exosomal miR-195 in hUC-MSCs alleviates hypoxia-induced damage of trophoblast cells through tissue factor pathway inhibitor 2.

MicroRNA-195 (miR-195) was decreased in the patients with pre-eclampsia (PE), which was implicated to modulate PE. Moreover, tissue factor pathway inhibitor 2 (TFPI2), which was highly expressed in the placenta of PE patients, was negatively correlated with miR-195 levels. This study aimed to explore the role of miR-195 in the cell therapy for the treatment of PE and the underlying mechanisms. Human umbilical cord mesenchymal stem cells (hUC-MSCs) were transfected with miR-195 mimic or mimic negative control to extract exosomes. HTR8/SVneo was incubated under hypoxia condition to induce cell damage, and co-co-cultured with exosomes derived from hUC-MSCs to evaluate its effect. Hypoxia time-dependently caused a decrease on miR-195 level with an increase on TFPI2 expression in HTR8/SVneo. MiR-195 directly bind to TFPI2 and inhibited TFPI2 expression in hUC-MSCs. Moreover, hypoxia-induced cell damage in HTR8/SVneo was significantly attenuated by co-culture with hUC-MSC-derived exosomes. Exosomes extracted from miR-195-overexpressed hUC-MSCs, could further ameliorate hypoxia-induced cell damage, due to the excessive amount of miR-195 delivered by exosomes. Exosomal miR-195 in hUC-MSCs alleviated hypoxia-induced cell damage through TFPI2, which might provide a potential therapeutic approach for pre-eclampsia.

Association of age at benign hysterectomy with leukocyte telomere length in a nationally representative population.

OBJECTIVES: Hysterectomy is one of the most common gynecological surgical procedures, and most hysterectomies are performed for benign indications. Despite the frequency and known benefits of the procedure, it remains unclear whether it has potential adverse effects on long-term health and longevity. The aim of this study was to evaluate the association of age at benign hysterectomy with leukocyte telomere length, in data from the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2002. STUDY DESIGN: In total, 811 women who had a hysterectomy were included in this cross-sectional study. MAIN OUTCOME MEASURES: To estimate the association of age at benign hysterectomy with telomere length, multivariate regression analyses adjusted for age, race/ ethnicity, education, marital status, income poverty ratio, body mass index (BMI), physical activity, smoking behavior, alcohol consumption, history of chronic disease and history of oophorectomy were conducted. Fitted smoothing curves were also evaluated. RESULTS: We found leukocyte telomere length was positively correlated with age at benign hysterectomy after adjusting for other confounders in both a minimally adjusted model [ß = 4.18, 95%CI: (0.17,8.20)] and a fully adjusted model [ß = 4.63, 95% CI:(0.56,8.70)]. CONCLUSIONS: Earlier age at benign hysterectomy was associated with shorter telomere length in a nationally representative population of women. These data provide new information in pre-surgical counseling and decision-making.

Immunologically modified enzyme-responsive micelles regulate the tumor microenvironment for cancer immunotherapy.

Immune checkpoint blockade has been proven to have great therapeutic potential and has revolutionized the treatment of tumors. However, various limitations remain, including the low response rate of exhausted T cells and mutual regulation of multiple immunosuppressive cell types that compromise the effect of single-target therapy. Nano-delivery systems can be used to regulate the tumor immune microenvironment in favor of immunotherapy. In this study, we constructed a polypeptide-based micellar system that encapsulates an aryl hydrocarbon receptor (AhR) inhibitor (CH223191) conjugated to T cell activator anti-CD28. The inhibition of AhR activation downregulates the fraction of immunosuppressive cells and effectively inhibits tumor cell metastasis. In addition, the combination with co-stimulatory antibodies improves T-cell activation and synergistically enhances the antitumor effect of AhR inhibitors. The micellar system developed in this study represents a novel and effective tumor immunotherapy approach.

Composite learning sliding mode synchronization of chaotic fractional-order neural networks.

In this work, a sliding mode control (SMC) method and a composite learning SMC (CLSMC) method are proposed to solve the synchronization problem of chaotic fractional-order neural networks (FONNs). A sliding mode surface and an adaptive law are constructed to update parameter estimation. The SMC ensures that the synchronization error asymptotically tends to zero under a strict permanent excitation (PE) condition. To reduce its rigor, online recording data together with instantaneous data is used to define a prediction error about the uncertain parameter. Both synchronization error and prediction error are used to construct a composite learning law. The proposed CLSMC method can ensure that the synchronization error asymptotically approaches zero, and it can accurately estimate the uncertain parameter. The above results obtained in the CLSMC method only requires an interval-excitation (IE) condition which can be easily satisfied. Finally, comparative results reveal the control effects of the two proposed methods.

Male mammary gland development after apatinib therapy in advanced gastric cancer: A case report.

RATIONALE: Most gastric cancer patients are diagnosed at mid- to late-stage and lose the chance of radical surgery, medical treatment is especially important to prolong the survival of patients. Apatinib mesylate, which is a small molecule vascular endothelial growth factor receptor 2 tyrosine kinase inhibitor, could be used as antiangiogenesis therapy for gastric cancer. PATIENT CONCERNS: A 67-year-old man sought medical care for upper abdominal discomfort. DIAGNOSIS: The patient was diagnosed as mixed medullary differentiated gastric adenocarcinoma, and immunohistochemistry suggested HER-2 (2+). INTERVENTIONS: The patient received chemotherapy consisting of oxaliplatin combined with S-1 as first-line treatment, and targeted therapy with apatinib mesylate as second-line treatment. OUTCOMES: After 4 months of first-line chemotherapy, the patient received apatinib treatment immediately at a dose of 500 mg/d orally and died of cardiac arrest with 8.5 months of overall survival. During this period of targeted therapy with apatinib mesylate, this male patient suffered mammary gland development besides other common adverse reactions. LESSONS: This case report is the first to report the case of male mammary gland development after oral apatinib.

Extensor muscle-preserving laminectomy in treating multilevel cervical spondylotic myelopathy compared with laminoplasty.

BACKGROUND: Laminectomy and laminoplasty are popularly used in posterior cervical spine surgery but still have involved complications. We aimed to compare the clinical outcomes of microscope-assisted extensor muscle-preserving laminectomy (MA-EMPL) and open-door laminoplasty (ODLP) in treating multilevel cervical spondylotic myelopathy (MCSM). METHODS: A prospective study was designed to enroll twenty patients with MCSM underwent MA-EMPL, and recruit twenty-four patients with MCSM received ODLP (control). Radiographic measurements, outcome indicators including Japanese Orthopedic Association (JOA) score and visual analogue score (VAS) were used to evaluate technical effectiveness. Surgical complications were documented to assess technical safety. RESULTS: Postoperative cervical curvature index and range of neck motion (ROM) were not significantly changed except ROM in ODLP group. Postoperative JOA score and VAS in both groups showed improvements at final follow-up. There was no statistical difference in postoperative neurological recovery rates between two groups (67.6%±17.8% vs. 70.15%±19.6%, P=0.632). However, VAS was significantly lower at postoperative 1 month in MA-EMPL group compared with ODLP group (P<0.001). The incidences of C5 palsy were 0 vs. 16.7% between MA-EMPL group and ODLP group. There was no axial symptom occurred in MA-EMPL group while six patients in ODLP group (0 vs. 25%, P=0.049). In addition, the mean blood loss and hospital stay were lesser in MA-EMPL group compared with ODLP group (P<0.001, P=0.002, respectively). CONCLUSIONS: MA-EMPL is an effective, safe and minimally invasive method in treatment of MCSM. Compared with ODLP, MA-EMPL has advantage to decrease intraoperative blood loss, hospital stay, postoperative VAS and axial symptom, as well as preserve postoperative ROM.

Dual-Blockade Immune Checkpoint for Breast Cancer Treatment Based on a Tumor-Penetrating Peptide Assembling Nanoparticle.

Cancer immunotherapy can enhance the antitumor effect of drugs through a combinatorial approach in a synergistic manner. However, the effective targeted delivery of various drugs remains a challenge. We generated a peptide assembling tumor-targeted nanodelivery system based on a breast cancer homing and penetrating peptide for the codelivery of a programmed cell death ligand 1 (PD-L1) small interfering RNA (siRNA) (siPD-L1) and an indoleamine 2,3-dioxygenase inhibitor as a dual blockade of an immune checkpoint. The vector is capable of specifically accumulating in the breast cancer tumor site in a way that allows the siRNA to escape from endosomal vesicles after being endocytosed by tumor cells. The drug within these cells then acts to block tryptophan metabolism. The results showed that locally released siPD-L1 and 1-methyl-dl-tryptophan favor the survival and activation of cytotoxic T lymphocytes, resulting in apoptosis of breast cancer cells. Therefore, this study provides a potential approach for treating breast cancer by blocking immunological checkpoints through the assembly of micelles with functional peptides.

CSN5 controls the growth of osteosarcoma via modulating the EGFR/PI3K/Akt axis.

CSN5, a critical subunit of the constitutive photomorphogenesis 9 (COP9) signalosome (CSN), functions as a potential tumor promoter in various cancers. However, the biological functions and clinical significance of CSN5 in osteosarcoma (OS) remains unclear. Here, we report that OS tumors overexpressed CSN5 compared with normal bone tissues, and CSN5 overexpression was obviously associated with the malignant phenotype and poor prognosis in patients with OS. In addition, high CSN5 expression significantly promoted the growth of OS cells, whereas CSN5 silence suppressed the tumorigenicity of OS cells. Furthermore, we found PI3K/Akt signaling pathway contributed to the effects of CSN5 in OS cells, and blocking the Akt pathway significantly inhibited the actions of CSN5. Mechanistically, we demonstrate that CSN5 positively regulated EGFR stability through reducing the levels of EGFR ubiquitination, thereby activating the PI3K/Akt signaling pathway in OS cells. Moreover, our results shown that the oncogenic effects of CSN5 on OS cells were EGFR dependent. Thus, CSN5 has a central role in regulating diverse aspects of the pathogenesis of OS, which could be a potential diagnostic and therapeutic target for OS.

Functional exosome-mediated co-delivery of doxorubicin and hydrophobically modified microRNA 159 for triple-negative breast cancer therapy.

Exosomes (Exo) hold great promise as endogenous nanocarriers that can deliver biological information between cells. However, Exo are limited in terms of their abilities to target specific recipient cell types. We developed a strategy to isolate Exo exhibiting increased binding to integrin αvß3. Binding occurred through a modified version of a disintegrin and metalloproteinase 15 (A15) expressed on exosomal membranes (A15-Exo), which facilitated co-delivery of therapeutic quantities of doxorubicin (Dox) and cholesterol-modified miRNA 159 (Cho-miR159) to triple-negative breast cancer (TNBC) cells, both in vitro and in vivo. The targeted A15-Exo were derived from continuous protein kinase C activation in monocyte-derived macrophages. These cell-derived Exo displayed targeting properties and had a 2.97-fold higher production yield. In vitro, A15-Exo co-loaded with Dox and Cho-miR159 induced synergistic therapeutic effects in MDA-MB-231 cells. In vivo, miR159 and Dox delivery in a vesicular system effectively silenced the TCF-7 gene and exhibited improved anticancer effects, without adverse effects. Therefore, our data demonstrate the synergistic efficacy of co-delivering miR159 and Dox by targeted Exo for TNBC therapy.

The Institute of Medicine recommendation for gestational weight gain is probably not optimal among non-American pregnant women: a retrospective study from China.

PURPOSE: To investigate whether the Institute of Medicine (IOM) recommended gestational weight gain (GWG) range is optimal among Chinese singleton pregnant women. METHODS: For the purpose of a retrospective observational study, data on 8209 mature singleton deliveries in Shanghai from January 2014 to December 2016 were extracted from medical records in terms of clinical performance. All cases were categorized as undergainers, appropriate-gainers, and above-gainers according to IOM recommended gestational weight gain range after stratification of maternal BMI and proportions of three categories were calculated. Comparisons of maternal and neonatal outcome were conducted among three categories and the associations of those outcome including risks of low birth weight (LBW) and macrosomia (MAC) with GWG were estimated by logistic regression analysis. To examine the applicability of IOM recommendation for Chinese pregnant women, the accumulated risk of LBW and MAC was displayed by stacked column chart and comparison was made among GWG category. The joint predicted risk (JPR) curve of both LBW and MAC in relation to GWG (continuous measurement) was plotted to demonstrate the relation of lowest JPR corresponding GWG with IOM range. RESULTS: The IOM recommended weight gain was achieved only by 3502 (42.7%) pregnant women and 41.6% gained excessive weight during pregnancy, especially for the overweight and obese women, the proportions of above-gainers mounting to 65.7 and 75.9%, respectively. By multivariate analysis GWG significantly influenced the risk of MAC and caesarean section. Although the association between the risk of LBW and GWG was not significant, p value reached .051. The risk of delivering macrosomia and caesarean section doubled when GWG exceeded the IOM rang. Appropriate gainers did not always gain the lowest joint risk of low birth weight and macrosomia from stacked column chart and it is obvious that the GWG point according to the lowest JPR was always located left to the IOM recommended range for each BMI category from the JPR curve chart in relation to GWG. CONCLUSIONS: The IOM recommended GWG range is possibly too much for Chinese singleton pregnant population for each BMI category. It is necessary to build different gestational weight gain standards for specific ethnic population.

Postoperative Cervical Sagittal Realignment Improves Patient-Reported Outcomes in Chronic Atlantoaxial Anterior Dislocation.

BACKGROUND: Chronic atlantoaxial anterior dislocation (AAD) not only results in myelopathy, but dislocation-related kyphosis also results in cervical malalignment, which permanently affects neck function and patient-reported outcomes (PROs). OBJECTIVE: To investigate the effect of kyphotic correction on realigning cervical spine and independent cervical alignment parameters, which may be correlated with an improvement of PROs. METHODS: The study included 21 patients with chronic AAD-related kyphosis who underwent C1-2 reduction and correction surgery. Radiographic parameters were measured to assess cervical realignment preoperatively and postoperatively. Neck disability index (NDI), short form 12 physical component summary (SF-12 PCS), and Japanese Orthopaedic Association (JOA) scores were recorded to reveal changes in PROs. The independent parameters correlated with the improvements of PROs were analyzed. RESULTS: Of the radiographic parameters, the C1-2 Cobb angle, the C2-7 Cobb angle, thoracic inlet angle, cervical tilt, and T1 slope were significantly changed from -4.0° ± 16.2°, -29.2° ± 11.2°, 73.1° ± 13.3°, 30.4° ± 8.5°, and 29.1° ± 8.8° preoperatively to -13.5° ± 8.1° (P = .005), -18.0° ± 12.0° (P < .001), 67.1° ± 11.6° (P = .042), 23.1° ± 10.3° (P = .007), and 24.0° ± 7.0° (P = .011) at last follow-up, respectively. NDI, JOA, and SF-12 PCS scores were significantly improved postoperatively. The C1-2 Cobb angle was an independent parameter correlated with the improvements in SF-12 PCS, NDI, and JOA scores. CONCLUSION: Correction and reduction surgery can realign cervical spine in chronic AAD patients. The C1-2 Cobb angle was an independent parameter correlated with the improvements of PROs.

The change of cervical spine alignment along with aging in asymptomatic population: a preliminary analysis.

STUDY DESIGN: A cross-sectional study. OBJECTIVE: To investigate the correlation of cervical spine alignment changes with aging in asymptomatic population. BACKGROUND: Previous studies demonstrated the influence of lumbar and thoracic spine on cervical spine alignment, but few has reported the cervical spine alignment change along with aging in asymptomatic population. METHODS: Asymptomatic population were divided into four groups according to different ages (Group A: ≤20 years; Group B: 21-40 years; Group C: 41-60 years; Group D: ≥61 years). Each group was composed of 30 subjects. The following parameters were measured: C0-1 Cobb angle, C1-2 Cobb angle, C2-7 Cobb angle, C1-7 sagittal vertical axis (C1-7 SVA), C2-7 SVA, central of gravity to C7 sagittal vertical axis (CG-C7 SVA), Thoracic Inlet Angle (TIA), Neck Tilt (NT), cervical tilt, cranial tilt, T1 slope (TS), TS-CL, and ANOVA statistical method was used to analyze the differences among four groups, and then, linear regression analysis was performed to analyze correlation of the cervical spine alignment with the aging. RESULTS: C1-7 SVA, C2-7 SVA, CG-C7 SVA, TIA, NT, TS, and cranial tilt were found statistically different among four groups (P < 0.01). From Group A to Group D, the mean C1-7 SVA were 30.7, 26.0, 21.8, and 36.9 mm, the mean C2-7 SVA were 18.7, 14.7, 11.9, and 24.7 mm, and the mean CG-C7 SVA were 19.6, 16.6, 9.4, and 26.7 mm. The mean TIA were 62.4°, 65.0°, 71.8°, and 76.9°, the mean NT were 39.4°, 43.8°, 46.3°, and 48.2°, the mean TS were 23.0°, 21.1°, 25.5°, and 28.7°, and the mean cranial tilt were 5.7°, 4.8°, 3.0°, and 9.5°. Further linear regression indicated that TIA (r = 0.472; P < 0.0001), NT (r = 0.337; P = 0.0006), and TS (r = 0.299; P = 0.0025) were positively correlated with aging. CONCLUSION: A gradual increase of TIA, NT, and TS, accompanied with an increased CL, is found along with aging in asymptomatic population, among which TIA, NT, and TS are significantly correlated with physiological nature of aging.

Coronal Multiplane Reconstructed Computed Tomography Image Determining Lateral Vertebral Notch-Referred Pedicle Screw Entry Point in Subaxial Cervical Spine: A Preclinical Study.

OBJECTIVE: To evaluate feasibility of computed tomography (CT) coronal multiplane reconstruction image (CMRI) to determine subaxial cervical pedicle screw (PS) entry point and guide lateral vertebral notch (LVN)-referred technique for subaxial cervical PS insertion. METHODS: Cervical CT scans were performed in 40 volunteers. PS entry point was determined by quantitating PS entry point related to LVN on CMRI. Pedicle mediolateral angle (α) and cephalocaudad angle (ß) were also measured to guide the trajectory of PS insertion. Based on these quantitations, 12 human cadaveric subaxial cervical pedicles were inserted with PS referring to LVN. Cortical integrity of each pedicle was evaluated after dissecting the cadaveric vertebrae one by one and confirmed by radiography and CT. The cortical penetration and PS position were classified into 4 grades: 0 (excellent position), I (good position), II (fair position), and III (poor position). RESULTS: On CT CMRI, PS entry point was consistently located approximately 2.2 mm medial to LVN from C3 to C7 and approximately 1.4 mm lower to LVN from C3 to C6, but 1.2 mm higher at C7. Bilateral α angle and ß angle showed substantial decrease from cranial to caudal. Cortical integrity of PS positions was excellent and good in 88.33%, fair in 8.33%, and poor in 3.33%. CONCLUSIONS: CMRI is reliable for determining subaxial cervical PS entry point. LVN is a consistent landmark for the notch-referred technique, which is a practical and easy to master technique for subaxial cervical spine PS insertion.

The accuracy of the lateral vertebral notch-referred pedicle screw insertion technique in subaxial cervical spine: a human cadaver study.

STUDY DESIGN: This is a cadaver specimen study to confirm new pedicle screw (PS) entry point and trajectory for subaxial cervical PS insertion. OBJECTIVE: To assess the accuracy of the lateral vertebral notch-referred PS insertion technique in subaxial cervical spine in cadaver cervical spine. BACKGROUNDS: Reported morphometric landmarks used to guide the surgeon in PS insertion show significant variability. In the previous study, we proposed a new technique (as called "notch-referred" technique) primarily based on coronal multiplane reconstruction images (CMRI) and cortical integrity after PS insertion in cadavers. However, the PS position in cadaveric cervical segment was not confirmed radiologically. Therefore, the difference between the pedicle trajectory and the PS trajectory using the notch-referred technique needs to be illuminated. METHODS: Twelve cadaveric cervical spines were conducted with PS insertion using the lateral vertebral notch-referred technique. The guideline for entry point and trajectory for each vertebra was established based on the morphometric data from our previous study. After 3.5-mm diameter screw insertion, each vertebra was dissected and inspected for pedicle trajectory by CT scan. The pedicle trajectory and PS trajectory were measured and compared in axial plane. The perforation rate was assessed radiologically and was graded from ideal to unacceptable: Grade 0 = screw in pedicle; Grade I = perforation of pedicle wall less than one-fourth of the screw diameter; Grade II = perforation more than one-fourth of the screw diameter but less than one-second; Grade III = perforation more than one-second outside of the screw diameter. In addition, pedicle width between the acceptable and unacceptable screws was compared. RESULTS: A total of 120 pedicle screws were inserted. The perforation rate of pedicle screws was 78.3% in grade 0 (excellent PS position), 10.0% in grade I (good PS position), 8.3% in grade II (fair PS position), and 3.3% in grade III (poor PS position). The overall accepted accuracy of pedicle screws was 96.7% (Grade 0 + Grade I + Grade II), and only 3.3% had critical breach. There was no statistical difference between the pedicle trajectory and PS trajectory (p > 0.05). Compared to the pedicle width (4.4 ± 0.7 mm) in acceptably inserted screw, the unacceptably screw is 3.2 ± 0.3 mm which was statistically different (p < 0.05). CONCLUSION: The accuracy of the notch-referred PS insertion in cadaveric subaxial cervical spine is satisfactory.