Increased ecological land and atmospheric CO2 dominate the growth of ecosystem carbon sinks under the regulation of environmental conditions in national key ecological function zones in China.

Increased ecological land (IEL) such as forests and grasslands can greatly enhance ecosystem carbon sinks. Understanding the mechanisms for the magnitude of IEL-induced ecosystem carbon sinks is crucial for achieving carbon neutrality. We estimated the impact of IEL, specifically the increase in forests and grasslands, as well as global changes including atmospheric CO2 concentration, nitrogen deposition, and climate change on net ecosystem productivity (NEP) in National Key Ecological Function Zones (NKEFZs) in China using a calibrated ecological process model. The NEP in NKEFZs in China was calculated to be 119.4 Tg C yr-1, showing an increase of 42.6 Tg C yr-1 from 2001 to 2021. Compared to the slight contributions of climate change (-8.0%), nitrogen deposition (11.5%), and reduction in ecological land (-3.5%), the increase in NEP was primarily attributed to CO2 (66.5%) and IEL (33.5%). Moreover, the effect of IEL (14.8 Tg C yr-1) surpassed that of global change (13.1 Tg C yr-1) in the land use change zone. The IEL-induced NEP is significantly associated with CO2 fertilization, regulated by precipitation and nitrogen deposition. The high values of IEL-induced NEP occurred in areas with precipitation exceeding 800 mm and nitrogen deposition exceeding 25 kg N ha-1 yr-1. We recommend prioritizing the expansion of ecological land in areas with sufficient water and nutrients to enhance CO2 fertilization, while avoiding increasing ecological land in regions facing unfavorable climate change conditions. This study serves as a foundation for comprehending the NEP response to ecological restoration and global change.

Improvement of ecosystem quality in National Key Ecological Function Zones in China during 2000-2015.

Improving ecosystem quality is the ultimate goal of ecological restoration projects and sustainable ecosystem management. However, previous results of ecosystem quality lack comparability among different regions when assessing the effectiveness of ecological restoration projects on the regional or national scales, due to the influence of geographical and climatic background conditions. Here we proposed a new index, ecosystem quality ratio (EQR), by integrating the status of landscape structure, ecosystem services, ecosystem stability, and human disturbance relative to their reference conditions, and assessed the EQR changes in China's counties and National Key Ecological Function Zones (NKEFZs) from 1990 to 2015. The results showed that the average ecosystem quality of China's counties deviated from the reference condition by 28%. EQR decreased by 1.2% during 1990-2000 but increased by 3.7% during 2000-2015. Those counties with increasing EQR in 2000-2015 occupy 64.7%, with obviously increasing counties mainly located in the water conservation, biodiversity maintenance, and water and soil conservation types of NKEFZs. The EQR increase in counties within NKEFZs was 3.65 times that outside of NKEFZs. Remarkable improvement of ecosystem quality occurred in the forest region in Changbai Mountain, biodiversity and soil conservation region in Wuling Mountains, and hilly and gully region of Loess Plateau, where EQR increases mainly resulted from the conversion of farmland to forest or grassland and consequent increases in ecosystem services and stability. The magnitude of EQR enhancement showed a positive relationship with the increase in forest and grassland coverage in NKEFZs. Our results highlight the important role of ecological restoration projects in improving ecosystem quality in China, and demonstrate the feasibility of the new index (EQR) for the assessment of ecosystem quality in terms of ecosystem management and restoration.

Case report: Epidural blood patches are effective in treating intracranial hypotension due to a subarachnoid-pleural fistula.

Background: Intracranial hypotension (IH) is usually associated with cerebrospinal fluid (CSF) leakage and/or CSF hypotension, and epidural blood patch (EBP) therapy has been proven to be effective for treating spontaneous IH and post-dural puncture headaches. Tarlov cysts (TCs) are common lesions of the sacral spine. They have rarely been reported in thoracic locations and are even less common in the posterior mediastinum, which can lead to their misdiagnosis as neurogenic tumors. Case presentation: Here, we report the case of a 60-year-old woman who developed an orthostatic headache after the thoracoscopic resection of a TC in the posterior mediastinum that was presumed to be a schwannoma preoperatively. The patient was finally diagnosed with IH caused by a subarachnoid-pleural fistula (SPF) and was cured by targeted EBP treatment. Conclusion: This is a case to show that a single targeted EBP treatment is effective for a patient with IH caused by an SPF after thoracoscopic resection of a TC. This case reminds us to be vigilant that a TC may be masquerading as a posterior mediastinal neurogenic tumor, and a detailed examination should be performed to identify it before deciding on a surgical procedure. In addition, postural headache after thoracoscopic spinal surgery should be alert to the possibility of IH induced by an SPF. Once it occurs, early treatment is necessary, and targeted EBP treatment can serve as a safe and effective alternative when conservative treatment fails.

Circ-FAT1 Up-Regulates FOSL2 Expression by Sponging miR-619-5p to Facilitate Colorectal Cancer Progression.

Circular RNA FAT atypical cadherin 1 (circ-FAT1) has been reported to play roles in colorectal cancer (CRC) development. Here, the purpose of this study was to investigate the function and mechanism of circ-FAT1 in CRC tumorigenesis and its potential value in the clinic. Levels of genes and proteins were examined by quantitative real-time polymerase chain reaction and Western blot. In vitro assays were conducted using cell counting kit-8 assay, 5-Ethynyl-2'-deoxyuridine assay, flow cytometry, transwell assay, and tube formation assay, respectively. The target relationship between miR-619-5p and circ-FAT1 or FOS-like antigen 2 (FOSL2) was verified by dual-luciferase reporter and RNA immunoprecipitation assays. In vivo assay was performed using a mouse subcutaneous xenograft model. Circ-FAT1 and FOSL2 were highly expressed in CRC tissues and cells. Functionally, knockdown of circ-FAT1 or FOSL2 suppressed CRC cell apoptosis, migration, invasion, and angiogenesis, but induced cell apoptosis in vitro. Mechanistically, circ-FAT1 acted as a sponge for miR-619-5p to up-regulate the expression of FOSL2, which was confirmed to be a target of miR-619-5p. A series of rescue experiments demonstrated that miR-619-5p inhibition or FOSL2 overexpression reversed the inhibitory action of circ-FAT1 silencing on CRC cell malignant phenotypes mentioned above. Pre-clinically, lentivirus-mediated circ-FAT1 knockdown inhibited the tumorigenesis of CRC xenografts in nude mice via regulating miR-619-5p and FOSL2. Circ-FAT1 knockdown repressed FOSL2 expression by sponging miR-619-5p to suppress CRC tumorigenesis, providing a potential approach for CRC therapeutics.

Abnormal placental DNA methylation variation in spontaneous preterm birth.

OBJECTIVE: Preterm birth (PTB) has become a major public health concern as the leading cause of neonatal death, but little is understood about its etiology. Children born preterm are also at increased risk of long-term consequences such as neurodevelopmental disorders, adulthood hypertension and diabetes. Recent studies have indicated that DNA methylation may be involved in the occurrence of PTB as well as related adverse outcomes. The latest Infinium EPIC BeadChip extends the coverage of the genome and provides a better tool to help investigate the involvement of DNA methylation in these conditions. METHODS: We conducted this case-control study in three Women and Children's hospitals in South China, and enrolled 32 spontaneous preterm births and 16 term births. We assessed placental DNA methylation profiling of these participants with the Infinium EPIC BeadChip. We identified PTB and gestational age (GA)-associated CpG sites with limma regression model, and applied seqlm to identify PTB-associated regions. We performed gene ontology analysis to further interpret functional enrichment of the identified differentially methylated genes in PTB. RESULTS: We identified a total of 8 differentially methylated positions (DMPs) that were significantly associated with PTB (FDR < 0.1) and a total of 15 DMPs that were associated with GA (FDR < 0.1). In the regional analysis, one differentially methylated region in the SLC23A1 gene overlapped with PTB-associated CpG site. The differentially methylated CpG sites in PTB were mapped to the genes involving in biological processes mainly regarding neurodevelopment, regulation of inflammation and metabolism. CONCLUSION: Our findings suggested that preterm placenta have distinct DNA methylation alterations, and these alteration patterns established at birth provide insight into the long-term consequences of preterm birth.

Exosomes Derived by SIRT1-Overexpressing Bone Marrow Mesenchymal Stem Cells Improve Pubococcygeus Muscle Injury in Rats.

BACKGROUND AND OBJECTIVES: To evaluate the effect of exosomes (Exos) derived from silent mating type information regulation 2 homolog 1 (SIRT1)-overexpressing human bone marrow mesenchymal stem cells (BMSCs) on the recovery of pubococcygeus muscle Injury. METHODS AND RESULTS: Exos isolated from SIRT1-overexpressing BMSCs (SIRT1/exos) were injected into a vaginal dilation-induced rat model of Stress urinary incontinence (SUI). The efficacy of Exos treatment on SUI was evaluated by determining the values of urodynamic parameters. The proliferation and differentiation of satellite cells (SCs) were examined by CCK-8 assay, Western blotting, and immunofluorescence staining. The mRNA and protein expression of molecules related to SC differentiation were detected by RT-qPCR and Western blotting, respectively. Treatment with SIRT1/exos significantly improved the values of abdominal leak point pressure (ALPP), maximum bladder volume (MBV), and estimated marginal mean in rats of SUI. Exposure of SIRT1/exos enhanced the proliferation, differentiation, and activation of SCs. Moreover, SIRT1/exos exhibited their positive effect on BMSCs by activating the ERK signaling. CONCLUSIONS: Our findings demonstrated that SIRT1/exos meliorated pubococcygeus muscle injury in rats by promoting ERK pathway, which may provide a novel cell-free therapeutic strategy for SUI.

Epithelioid angiomyolipoma of the pancreas: A case report and review of the literature.

BACKGROUND: Angiomyolipomas (AMLs), belonging to the family of mesenchymal tumors, are considered benign lesions that occur mostly in the kidney or as a part of tuberous sclerosis. Epithelioid AML (EAML) is a rare type of AML that appears to have malignant potential. Extrarenal AMLs usually occur in the liver according to the retrieved literature reports. There have been only two previous reports of monofocal primary AML of the pancreas; however, no cases of primary monotypic EAML of the pancreas have been reported. CASE SUMMARY: An asymptomatic 59-year-old woman incidentally revealed a tumor during abdominal ultrasound examination. Routine blood tests and physical examination were within normal limits. Abdominal ultrasound revealed a 1.9-cm hypoechogenic mass in the tail of the pancreas, clearly visualized by endoscopic ultrasound. However, contrast-enhanced abdominal computed tomography scans did not demonstrate the lesion. A subsequent gadolinium-enhanced magnetic resonance imaging scan showed that the lesion had some characteristic manifestations. The lesion was initially thought to be a neuroendocrine tumor (asymptomatic PanNET). After surgical resection, histopathology and immunohistochemistry confirmed the diagnosis of EAML. At the 6-mo follow-up, no recurrence, spread, or metastasis was identified on computed tomography or magnetic resonance imaging. CONCLUSION: The preoperative diagnosis of pancreatic AML is extremely difficult. Imaging techniques are essential for providing valuable morphological features for differential diagnosis.

Pulmonary artery trunk enlargement on admission as a predictor of mortality in in-hospital patients with COVID-19.

PURPOSE: To describe the prognostic value of pulmonary artery (PA) trunk enlargement on the admission of in-hospital patients with severe COVID-19 infection by unenhanced CT image. MATERIALS AND METHODS: In-hospital patients confirmed COVID-19 from January 18, 2020, to March 7, 2020, were retrospectively enrolled. PA trunk diameters on admission and death events were collected to calculate the optimum cutoff using a receiver operating characteristic curve. According to the cutoff, the subjects on admission were divided into two groups. Then the in-hospital various parameters were compared between the two groups to assess the predictive value of PA trunk diameter. RESULTS: In the 180 enrolled in-hospital patients (46.99 ± 14.95 years; 93 (51.7%) female, 14 patients (7.8%) died during their hospitalization. The optimum cutoff PA trunk diameter to predict in-hospital mortality was > 29 mm with a sensitivity of 92.59% and a specificity of 91.11%. Kaplan-Meier survival curves for PA trunk diameter on admission showed that a PA trunk diameter > 29 mm was a significant predictor of subsequent death (log-rank < 0.001, median survival time of PA > 29 mm was 28 days). CONCLUSION: PA trunk enlargement can be a useful predictive factor for distinguishing between mild and severe COVID-19 disease progression.

Odontoid calcification and crowned dens syndrome: data from a Chinese center.

OBJECTIVES: To assess the prevalence of calcification surrounding the odontoid process (odontoid calcification) with crowned dens syndrome (CDS) and without CDS (non-CDS) and investigate factors that may related to the onset of CDS. METHODS: Retrospective review of consecutive patients visited Sir Run Run Shaw Hospital between 1 January 2018 and 5 November 2019 who were identified to have odontoid calcification on cervical computed tomography (CT) images. Those who presented with an acute or subacute episode of cervico-occipital pain were defined as CDS, others were non-CDS. RESULTS: We diagnosed 69 cases of odontoid calcification among 2902 cervical CTs of 2556 patients (69/2556, 2.70%), 19 (19/2556, 0.74%) cases of which were CDS, 50 (50/2556, 1.96%) cases were non-CDS. Mean age was 71 (54-86) years old in odontoid calcification patients. The male-to-female ratio of patients with odontoid calcification was 27:42 (0.64). The prevalence of odontoid calcification was 69/1497 (6.14%) in individuals over 50 years old, The prevalence was 0.59% (4/679), 5.05% (26/515), 11.49% (27/235) and 20% (12/60) in patients aged 50-59, 60-69, 70-79 and 80-89 years old, respectively. Age and female gender were predictive factors of odontoid calcification. Lower hemoglobin (Hgb), red blood cell count (RBC), higher C-reactive protein (CRP), pain scale score were found in CDS patients comparing with non-CDS group. No difference of age, gender, hypertension, diabetes mellitus, smoking, alcohol history, creatinine, white blood cell count, mean corpuscular volume, uric acid, calcium was found between the two groups. CONCLUSIONS: Odontoid calcification is a common radiological entity in patients older than 50 years. Lower Hgb, RBC, higher CRP, pain scale score were found in CDS patients comparing with non-CDS.

Comparison of DNA methylation profiles associated with spontaneous preterm birth in placenta and cord blood.

BACKGROUND: The etiology and mechanism of spontaneous preterm birth (sPTB) are still unclear. Accumulating evidence has documented that various environmental exposure scenarios may cause maternal and fetal epigenetic changes, which initiates the focus on whether epigenetics can contribute to the occurrence of sPTB. Therefore, we conducted the current study to examine and compare the DNA methylation changes associated with sPTB in placenta and cord blood. METHODS: This hospital-based case-control study was carried out at three Women and Children's hospitals in South China, where 32 spontaneous preterm births and 16 term births were recruited. Genome-wide DNA methylation profiles of the placenta and cord blood from these subjects were measured using the Illumina HumanMethylation EPIC BeadChip, and sPTB-associated differential methylated CpG sites were identified using limma regression model, after controlling for major maternal and infant confounders. Further Gene Ontology analysis was performed with PANTHER in order to assess different functional enrichment of the sPTB-associated genes in placenta and cord blood. RESULTS: After controlling for potential confounding factors, one differentially methylated position (DMP) in placenta and 31 DMPs in cord blood were found significantly associated with sPTB (Bonferroni corrected p < 0.05). The sPTB-associated CpG sites in placenta were mapped to genes that showed higher enrichment on biological processes including biological regulation, multicellular organismal process, and especially response to stimulus, while those in cord blood were mapped to genes that had higher enrichment on biological processes concerning cellular process, localization, and particularly metabolic process. CONCLUSION: Findings of this study indicated that DNA methylation alteration in both placenta and cord blood are associated with sPTB, yet the DNA methylation modification patterns may appear differently in placenta and cord blood.

Preoperative computed tomography diagnosis of non-recurrent laryngeal nerve in patients with esophageal carcinoma.

BACKGROUND: The non-recurrent laryngeal nerve (NRLN) is a rare but potentially serious anomaly that is commonly associated with the aberrant right subclavian artery (ARSA). It is easy to damage during surgical resection of esophageal cancer, leading to severe complications. METHODS: Preoperative enhanced thoracic computed tomography (CT) scans of 2697 patients with esophageal carcinoma treated in our hospital between January 2010 and December 2013 were examined. We classified the positional relationship between the right subclavian artery and the membranous wall of the trachea into two types and used this method to predicate NRLN by identifying ARSA. RESULTS: Twenty-six patients (0.96%) were identified with ARSA, all of which were cases of NRLN by CT. NRLN was identified during surgery in the 26 patients, and a normal right recurrent laryngeal nerve was observed in 2671 patients. The ARSA was detected on the dorsal side of the membranous wall of the trachea in all 26 NRLN cases, while it was detected on the ventral side in all 2671 recurrent laryngeal nerve cases. CONCLUSION: Enhanced CT scanning is a reliable method for predicting NRLN by identifying ARSA. Preoperative recognition of this nerve anomaly allows surgeons to avoid damaging the nerve and abnormal vessels during esophagectomy.

Probing Resonances of the Dirac Equation with Complex Momentum Representation.

Resonance plays critical roles in the formation of many physical phenomena, and several methods have been developed for the exploration of resonance. In this work, we propose a new scheme for resonance by solving the Dirac equation in the complex momentum representation, in which the resonant states are exposed clearly in the complex momentum plane and the resonance parameters can be determined precisely without imposing unphysical parameters. Combined with the relativistic mean-field theory, this method is applied to probe the resonances in ^{120}Sn with the energies, widths, and wave functions being obtained. Compared to other methods, this method is not only very effective for narrow resonances, but also can be reliably applied to broad resonances.

[MiRNA224 Regulation Role on RKIP Gene Expression and Methylation of miRNA224 Gene Promoter Region in Esophageal Squamous Cell Carcinoma].

OBJECTIVES: To study the expression levels of tumor suppressor gene RIKP and miRNA224 in esophageal squamous cell carcinoma (ESCC) tissues. To determine whether miRNA224 targets RKIP and the methylation status of miRNA224 gene promoter region in esophageal carcinoma. METHODS: The expression levels of RKIP and miRNA224 in ESCC and normal tissue were detected by using immunohistochemistry and real-time qPCR, respectively. Luciferase assay was used to determine the targeting of miRNA224 to RKIP. The methylation status of miRNA224 promoter region was studied by bisulfite sequencing PCR (BSP). RESULTS: In 40 cases of ESCC, RKIP expression was significantly lower than that of normal tissue; miRNA224 expression was higher in ESCC than in paracancerous tissue. Luciferase assay showed that miRNA224 targets RKIP 3'UTR thus inhibit its expression. The miRNA224 gene promoter region was hypomethylated in ESCC. CONCLUSIONS: Compared with normal tissue, in ESCC, RKIP was downregulated, while miRNA224 was upregulated, and the promoter region of miRNA224 gene was hypomethylated. RKIP is the target of miRNA224, which may be closely related to esophageal squamous cell carcinoma.

Effects of neutrophil elastase inhibitor in patients undergoing esophagectomy: a systematic review and meta-analysis.

AIM: To evaluate the benefit and safety of sivelestat (a neutrophil elastase inhibitor) administration in patients undergoing esophagectomy. METHODS: Online databases including PubMed, EMBASE, the Cochrane Library, Web of Knowledge, and Chinese databases (Wanfang database, VIP and CNKI) were searched systematically up to November 2013. Randomized controlled trials and high-quality comparative studies were considered eligible for inclusion. Three reviewers evaluated the methodological quality of the included studies, and Stata 12.0 software was used to analyze the extracted data. The risk ratio (RR) was used to express the effect size of dichotomous outcomes, and mean difference (MD) or standardized mean difference was used to express the effect size of continuous outcomes. RESULTS: Thirteen studies were included in this systematic review and nine studies were included in the meta-analysis. The duration of mechanical ventilation was significantly decreased in the sivelestat group on postoperative day 5 [I (2) = 76.3%, SMD = -1.41, 95%CI: -2.63-(-0.19)]. Sivelestat greatly lowered the incidence of acute lung injury in patients after surgery (I (2) = 0%, RR = 0.27, 95%CI: 0.08-0.93). However, it did not decrease the incidence of pneumonia, intensive care unit stay or postoperative hospital stay, and did not increase the incidence of complications such as anastomotic leakage, recurrent nerve palsy, wound infection, sepsis and catheter-related fever. CONCLUSION: A neutrophil elastase inhibitor is beneficial in patients undergoing esophagectomy. More high quality, large sample, multi-center and randomized controlled trials are needed to validate this effect.

CHRNA3 rs6495308 genotype as an effect modifier of the association between daily cigarette consumption and hypertension in Chinese male smokers.

Cigarette smoking is an important risk factor for hypertension. However, the effects on hypertension of the interaction between smoking and the genotype of the nicotinic acetylcholine receptor gene are unclear. The purpose of this study is to determine whether the CHRNA3 rs6495308 genotype affects the association between daily cigarette consumption and hypertension. We recruited 947 male smokers in southern China and used a questionnaire administered in face to face interviews to obtain information on their socio-demographic characteristics and smoking behavior. Blood samples were collected to test for CHRNA3 rs6495308 genotype variations. Three blood-pressure measurements were taken for each participant, and the average values recorded. We found that, compared with light smoking (<15 cigarettes per day), heavy smoking (≥15 cigarettes per day) yielded a greater risk of hypertension. We also observed that the interaction between daily cigarette consumption and the CHRNA3 rs6495308 genotype may affect hypertension. Heavy smokers with the homozygous mutant CHRNA3 rs6495308 genotype exhibited a significantly greater risk of hypertension than light smokers with wild-type CHRNA3 rs6495308 genotypes. The positive interaction between heavy smoking and the homozygous mutant CHRNA3 rs6495308 genotype was found to affect the likelihood of hypertension in Chinese male smokers.

Successful removal of a giant pulmonary hamartoma coexisting with an anomalous common pulmonary venous trunk.

We present an extremely rare case of a giant pulmonary hamartoma (PH) coexisting with an anomalous common pulmonary venous trunk (ACPVT). An asymptomatic 39-year-old man was referred for evaluation of a giant pulmonary lesion in his left thorax detected on chest X-ray during a routine medical examination. After clinical work-up, the patient underwent left exploratory thoracotomy. Since the extent of the tumor and coexistence of an ACPVT, a left pneumonectomy was performed. The specimen measured 28 cm × 18 cm × 17 cm and weighted for 2.1 kg. Histology revealed a blend of pieces of rounded cartilage separated by fibrous bands in which mature adipose tissue and cleft-like structures lined. The features were consistent with those of a chondromatous hamartoma. The patient made a satisfactory recovery and 10 months after the operation was asymptomatic.

Does tumour location influence postoperative long-term survival in patients with oesophageal squamous cell carcinoma?

OBJECTIVES: The seventh edition of the American Joint Committee on Cancer (AJCC) staging system introduced tumour location for the first time as an determinant of stage grouping in pathological T2N0M0 and T3N0M0 (pT2-3N0M0) oesophageal squamous cell carcinoma (OSCC). However, the new modification remains controversial. The objective of this study was to investigate the correlation between tumour location and postoperative long-term survival in patients with OSCC in China. METHODS: The clinicopathological data and over 10 years of follow-up results from a large cohort of 988 patients with OSCC undergoing radical-intent oesophagectomy from 1984 to 1995 without preoperative and postoperative chemoradiotherapy were reviewed, in which 632 patients were staged as pT2-3N0M0. Tumour location was redefined according to the seventh edition of the AJCC staging system. Survival was calculated by the Kaplan-Meier method; univariate log-rank and multivariate Cox proportional hazard models were used to further determine the impact of tumour location on long-term survival. RESULTS: Univariate analysis showed that OSCC tumour location was closely associated with long-term survival for the entire cohort of 988 patients (odds ratio [OR]: 0.82; 95% confidence interval [95% CI]: 0.67-0.99; P = 0.049), and for pT2-3N0M0 patients (OR: 0.63; 95% CI: 0.48-0.84; P = 0.001). The median survival times for patients with pT2-3N0M0 OSCC in the upper, middle and lower third of the oesophagus were 38.1, 46.6 and 66.0 months, respectively, with corresponding 5-year survival rates of 40.0, 51.8 and 66.2%, respectively. Overall survival rates among three categories of patients according to tumour location in the pT2-3N0M0 patients were statistically different (P = 0.004). Multivariate analysis demonstrated that tumour location was a significant independent predictor of long-term survival for pT2-3N0M0 patients (OR: 0.53; 95% CI: 0.42-0.67; P = 0.0001), but not for the entire cohort of 988 patients (OR: 0.99; 95% CI: 0.79-1.23; P = 0.90). CONCLUSIONS: Tumour location is an independent predictor of long-term survival for pathological T2-3N0M0 OSCC, and should be incorporated into the current staging system to predict long-term survival and identify high-risk postoperative patients.

Soft tissue image reconstruction using cone-beam computed tomography combined with laser scanning: a novel method to evaluate the masticatory mucosa.

OBJECTIVE: To construct a 3-D model of the masticatory mucosa to measure the thickness of the facial/lingual gingiva and palatal mucosa. STUDY DESIGN: Maxillofacial regions of 8 volunteers were scanned using cone-beam computed tomography to generate 3-D maxillary and mandibular models. Digital models were obtained by laser scanning of the impressions. Models were constructed using global data registration and Boolean subtraction. Accuracy was assessed by comparison against control patients with a periodontal pack around their gingival boundaries. Inter- and intra-observer variability were determined. RESULTS: Masticatory mucosa models (in stereolithography format) showed the gingival and mucosal contours. The gingival thickness of the 3-D models and controls were not significantly different (P > .05). The interclass correlation coefficient and Kappa values indicated good intra-observer and inter-observer agreement, respectively. CONCLUSIONS: Cone-beam computed tomography combined with laser scanning can be reliable for visualizing and measuring the thickness of the masticatory mucosa.

[Effects of hypergravity exposure after 30 days of simulated weightlessness on chemokine CCL20 and its receptor CCR6 in gingival tissue of rhesus macaque].

PURPOSE: To study the effect of hypergravity exposure after 30 days of simulated weightlessness on the expression of chemokine CCL20 and its receptor CCR6 in gingival tissue of rhesus macaque. METHODS: Twenty-three male rhesus monkeys were randomly divided into 4 groups, namely control group (A,n=3), weightlessness group (B,n=3), hypergravity group (C,n=3) and hypergravity exposure after 30 days of simulated weightlessness group (D, n=14). Group D was further divided into 4 subgroups according to the values of overload as: +11 Gx /270 s group (D1, n=3), +13 Gx /230 s group (D2,n=4), +15 Gx/200 s group (D3,n=4) and +13 Gx /230 s with 9 days of recovery group (D4, n=3). Histopathological changes of gingival tissues were observed by hematoxylin-eosin staining and the expressions of CCL20 and CCR6 were detected by immunohistochemistry (IHC) and quantitative real-time PCR (Q-PCR). SPSS 17.0 software package was used for statistical analysis. RESULTS: Histological observation showed that no significant histopathological change was found in the gingival tissues in all experimental groups. However, there were more infiltrated lymphocytes and neutrophils in the experimental groups. Normal gingival epithelial cells were hardly stained by anti-CCL20 but weakly stained by anti-CCR6. In the experimental groups, CCL20 could be detected in the basal layer of the gingival epithelial tissue, and CCR6 could be detected in the spinous layer and the basal layer of the gingival epithelium. The CCL20 and CCR6 expression in the gingival tissues of each experimental group were significantly higher than those of the control group, not only at the protein level but at the mRNA level (P<0.05) except the CCL20 expression in the weightlessness group. CONCLUSIONS: Hypergravity exposure after 30 days of simulated weightlessness will not lead to significant pathological changes in gingival tissues, but can induce the expression of chemokine CCL20 and its receptor CCR6 in gingival tissue.

Probing the symmetries of the Dirac Hamiltonian with axially deformed scalar and vector potentials by similarity renormalization group.

Symmetry is an important and basic topic in physics. The similarity renormalization group theory provides a novel view to study the symmetries hidden in the Dirac Hamiltonian, especially for the deformed system. Based on the similarity renormalization group theory, the contributions from the nonrelativistic term, the spin-orbit term, the dynamical term, the relativistic modification of kinetic energy, and the Darwin term are self-consistently extracted from a general Dirac Hamiltonian and, hence, we get an accurate description for their dependence on the deformation. Taking an axially deformed nucleus as an example, we find that the self-consistent description of the nonrelativistic term, spin-orbit term, and dynamical term is crucial for understanding the relativistic symmetries and their breaking in a deformed nuclear system.