Construction and evaluation of fibrillar composite hydrogel of collagen/konjac glucomannan for potential biomedical applications

Konjac glucomannan (KGM) is recognized as a safe material for its health-promoting benefits and thus widely used in various fields including pharmaceutical industry. In recent decades, the combination of collagen and KGM attracts more attentions for biomedical purpose, especially the hybrid films of collagen–KGM or collagen–KGM–polysaccharide. In this study, to further and deeply develop the intrinsic values of both collagen and KGM as biomaterials, a novel kind of composite hydrogel comprising collagen and KGM at a certain ratio was fabricated under mild conditions via fibrillogenesis process of the aqueous blends of collagen and KGM that experienced deacetylation simultaneously. The chemical composition, microcosmic architectures, swelling behavior, biodegradation and dynamic mechanic properties of such resulted composite hydrogels were systematically investigated. Biologic experiments, including cell culture in vitro and hypodermic implantation in vivo, were also conducted on these collagen/KGM composite hydrogels to evaluate their biologic performances. The relevant results prove that, based on collagen self-assembly behavior, this synthesis strategy is efficient to construct a composite hydrogel of collagen/KGM with improved mechanical properties, biodegradability, excellent biocompatibility and bioactivity, which are promising for potential biomedical applications such as tissue engineering and regenerative medicine.

[Clinical analysis of the specific reference intervals of thyroid index for normal pregnant women]

Objective: To explore the reference intervals of thyrotropin (TSH) and free thyroxine (FT(4)) in normal pregnant women. Methods: Prospective and longitudinal sequential collection of the cases were performed. A total of 155 singleton pregnant women who had regular prenatal examination and delivery in West China Second Hospital of Sichuan University from January 2015 to December 2015 were included as the research group. Blood samples were sequentially collected from the pregnant women at the first (9-13(+6) weeks) , the second (24-27(+6) weeks) , the third (32-36 weeks) trimesters, respectively. Another 155 non-pregnant women were selected as the control group simultaneously, in an effort to establish a range of reference intervals of thyroid index in each period of pregnancy. Meanwhile, neonatal plantar blood were also collected on special filter paper and TSH levels were measured. Results: (1) TSH reference intervals [percentile 2.5-percentile 97.5 (P(2.5)-P(97.5)) ] were 0.08-3.29 mU/L, 0.59-4.22 mU/L and 0.81-4.33 mU/L in three trimesters respectively. FT(4) reference intervals were 11.88-20.06 pmol/L, 9.89-15.80 pmol/L and 9.22-15.77 pmol/L in three trimesters respectively. (2) The median serum TSH in the first trimester (1.35 mU/L) was lower than that in the second trimester (2.15 mU/L) , the third trimester (2.19 mU/L) , and the control group (2.19 mU/L) . The differences were all statistically significant (P<0.05) . There was no significant difference in median serum TSH between the second trimester and the third trimester, the second trimester and the control group, and the third trimester versus the control group. (3) The median serum FT(4) in the first trimester (15.16 pmol/L) was higher than that in the second trimester (12.39 pmol/L) and the third trimester (12.26 pmol/L) . The differences were both statistically significant (P<0.05) . The median FT(4) in the second trimester and the third trimester was lower than that in the control group (15.64 pmol/L) , and the differences were both statistically significant (P<0.05) . (4) In the first trimester, the median serum total triiodothyronine (TT(3)) level (2.32 nmol/L) was higher than that in the control group (1.56 nmol/L) , total thyroxine (TT(4)) level (154.60 nmol/L) was also higher than that in the control group (98.25 nmol/L) , and free triiodothyronine (FT(3)) level (4.70 pmol/L) was lower than that in the control group (4.84 pmol/L) , the differences were all statistically significant (P<0.05) . (5) The TSH levels of all neonatus were normal [ (2.1±1.3) mU/L]. Conclusions: The thyroid hormone levels between pregnant women and non-pregnant women are significantly different. Moreover, the reference intervals are vary with pregnancy period. It is important to establish the specific reference intervals of thyroid hormones in the first, second and third trimester of pregnancy specific to local region or unit.

Multiregion whole-exome sequencing of matched primary and metastatic tumors revealed genomic heterogeneity and suggested polyclonal seeding in colorectal cancer metastasis

Background

Distant metastasis accounts for 90% of deaths from colorectal cancer (CRC). Genomic heterogeneity has been reported in various solid malignancies, but remains largely under-explored in metastatic CRC tumors, especially in primary to metastatic tumor evolution.

Patients and methods

We conducted high-depth whole-exome sequencing in multiple regions of matched primary and metastatic CRC tumors. Using a total of 28 tumor, normal, and lymph node tissues, we analyzed inter- and intra-individual heterogeneity, inferred the tumor subclonal architectures, and depicted the subclonal evolutionary routes from primary to metastatic tumors.

Results

CRC has significant inter-individual but relatively limited intra-individual heterogeneity. Genomic landscapes were more similar within primary, metastatic, or lymph node tumors than across these types. Metastatic tumors exhibited less intratumor heterogeneity than primary tumors, indicating that single-region sequencing may be adequate to identify important metastasis mutations to guide treatment. Remarkably, all metastatic tumors inherited multiple genetically distinct subclones from primary tumors, supporting a possible polyclonal seeding mechanism for metastasis. Analysis of one patient with the trio samples of primary, metastatic, and lymph node tumors supported a mechanism of synchronous parallel dissemination from the primary to metastatic tumors that was not mediated through lymph nodes.

Conclusions

In CRC, metastatic tumors have different but less heterogeneous genomic landscapes than primary tumors. It is possible that CRC metastasis is, at least partly, mediated through a polyclonal seeding mechanism. These findings demonstrated the rationale and feasibility for identifying and targeting primary tumor-derived metastasis-potent subclones for the prediction, prevention, and treatment of CRC metastasis.

Electrodynamic Heart Model Construction and ECG Simulation

Objectives: In this paper, we present a unified electrodynamic heart model that permits simulations of the body surface potentials generated by the heart in motion. The inclusion of motion in the heart model significantly improves the accuracy of the simulated body surface potentials and therefore also the 12-lead ECG.

Methods: The key step is to construct an electromechanical heart model. The cardiac excitation propagation is simulated by an electrical heart model, and the resulting cardiac active forces are used to calculate the ventricular wall motion based on a mechanical model. The source-field point relative position changes during heart systole and diastole. These can be obtained, and then used to calculate body surface ECG based on the electrical heart-torso model.

Results: An electromechanical biventricular heart model is constructed and a standard 12-lead ECG is simulated. Compared with a simulated ECG based on the static electrical heart model, the simulated ECG based on the dynamic heart model is more accordant with a clinically recorded ECG, especially for the ST segment and T wave of a V1-V6 lead ECG. For slight-degree myocardial ischemia ECG simulation, the ST segment and T wave changes can be observed from the simulated ECG based on a dynamic heart model, while the ST segment and T wave of simulated ECG based on a static heart model is almost unchanged when compared with a normal ECG.

Conclusions: This study confirms the importance of the mechanical factor in the ECG simulation. The dynamic heart model could provide more accurate ECG simulation, especially for myocardial ischemia or infarction simulation, since the main ECG changes occur at the ST segment and T wave, which correspond with cardiac systole and diastole phases.

[Clinical features and prognosis of 18 cases of primary lymphocytic hypophysitis]

Objective: To analyze clinical features, prognosis and treatment of lymphocytic hypophysitis (LYH). Methods: The clinical data, treatments and outcomes of 18 cases diagnosed as LYH at Chinese PLA General Hospital between January 2001 and July 2017 was respectively reviewed. Results: Eighteen patients with histology-proven LYH (13 females and 5 males ) were identified. All lymphocytic adenohypophysitis (LAH) were females(n=6), two of whom were associated with pregnancy. Eleven patients (6 females and 5 males) had lymphocytic panhypophysitis (LPH) and one(female) had hypothalamitis. Pre-treatment evaluation revealed that 11 patients presented with symptoms of intracranial space-occupying lesions, 12 patients had symptoms of anterior pituitary hormone deficiencies, and 12 patients had central diabetes insipidus (CDI). All patients had space-occupying lesions on magnetic resonance imaging (MRI), which were symmetrically enlarged and homogenously enhanced with or without pituitary stalk thickening. Before or after surgery, 11 patients received immunosuppressant therapy or radiotherapy to alleviate space-occupying effect. After 4-204 months follow-up, 5 patients had a relapse and received immunosuppressants, radiotherapy or surgery to achieve remission. Full recovery (both symptomatic and radiographic) was seen in 6 patients, and 11 patients maintained stable replacement therapy. Conclusions: LYH presents with acute space-occupying effects such as headache, visual disturbances, hypopituitarism, CDI and mild hyperprolactinemia, especially with characteristic radiographic manifestations. Usually, surgery reliably establishes diagnosis, and immunosuppressant therapy is a necessity. On the whole, LYH has a good prognosis.

Distribution and quantitative analysis of CIDEa and CIDEc in broiler chickens: accounting for differential fat deposition between strains

1. Differences in the expression of CIDEa and CIDEc in 20 different tissues were examined. Both CIDEa and CIDEc mRNA transcripts were predominantly but variably expressed in white adipose tissue (WAT) but were also expressed at moderate levels in the kidney and liver and at lower levels in the ovary. Interestingly, among WAT types, both CIDEa and CIDEc were expressed at the lowest levels in heart coronary WAT. 2. To better understand the roles of CIDEa and CIDEc in the fat deposition of broiler chickens, the differences in lipid droplet (LD) size and mRNA levels of CIDEa and CIDEc between lean-type and fat-type broiler chicken lines were studied. LD sizes were larger in fat-type broiler lines, and CIDEa and CIDEc mRNA levels in white adipose, kidney and liver tissues were significantly higher in fat-type broiler lines than in their lean counterparts. 3. Developmental expression patterns of CIDEa and CIDEc mRNA were analysed in different tissue types (WAT, liver and kidney) in Arbor Acres broiler chickens, and CIDEa and CIDEc mRNA expression levels increased during sequential developmental stages, achieving peak expression levels at week 6. 4. These observations suggest that the functions of CIDEa and CIDEc reflect inherent characteristics of lipid metabolism that contribute to the differences in fat deposition between strains. The results in this study contribute to a more robust understanding of the tissue distribution and expression patterns of CIDEa and CIDEc mRNA and facilitate further research concerning the molecular mechanism underlying fat deposition in broiler chickens.

miR-146a rs2910164 polymorphism might be associated with coronary artery disease risk in Asians

Recently, several studies reported the association between miR-146a rs2910164 polymorphism and coronary artery disease (CAD) risk. However, the results were inconclusive. We therefore did a meta-analysis to investigate this association. Electronic databases, including PubMed, EMBASE, and China National Knowledge Infrastructure (CNKI) databases, were searched. The strength of association was assessed by calculating odds ratios (OR) and 95% confidence interval (CI). Five eligible studies included in this meta-analysis. The total sample size of this meta-analysis was 1565 cases and 1541 controls. We found that miR-146a rs2910164 polymorphism was significantly associated with an increased CAD risk (OR = 1.19; 95% CI 1.07 - 1.32; P = 0.002). In the subgroup analysis by race, miR-146a rs2910164 polymorphism was significantly associated with an increased CAD risk in Asians (OR = 1.18; 95% CI 1.04 - 1.33; P = 0.008). However, we did not find significant result in Caucasians (OR = 1.22; 95% CI 0.86 - 1.74; P = 0.25). In the subgroup analysis by age, we found that miR-146a rs2910164 polymorphism increased CAD risk in old population (OR = 1.22; 95% CI 1.09 - 1.38; P = 0.0008). In conclusion, this meta-analysis found that miR-146a rs2910164 polymorphism was significantly associated with CAD risk.

[Characterization of N-linked glycosylation sites on envelope proteins of simian/human immunodeficiency virus in peripheral blood of Chinese rhesus macaques during acute infection]

Objective: To investigate the number and distribution of N-linked glycosylation sites of simian/human immunodeficiency virus envelope proteins(SHIV_SF162P3)and SHIV transmission. Methods: Two female adult Chinese rhesus macaques(4 years old)were intravenously inoculated with 300 TCID50 SHIV_SF162P3. The macaques weighed 4 and 5 kg and were identified as Rh1 and Rh2. We collected plasma samples at days 3, 7, 10, 14, 17, 21, 24, 28, 35, 42, 49, 56, 63, 70 and 77 post-challenge. Subsequently, we monitored plasma viral load by real-time PCR after viral RNA isolation and cDNA synthesis. We amplified the full-length envelope gene by single genome amplification(SGA)at days 7, 14, 28 and 77. BioEdit, MEGA, and the HIV Databases were used to analyze envelope sequences. Sequence diversity and N-linked glycosylation sites were compared between virus stock and plasma viruses of the two macaques. Results: A total of 55 env sequences were obtained from virus stock and their average pairwise distances were(0.166 6± 0.096 3)%. Viral loads peaked at 7.68 and 7.49 log10 copies/ml at day 10 and reached the set point at day 42(4.27 and 4.81 log10 copies/ml). The percentages of envelope sequences containing 25 potential N-linked glycosylation sites(PNGSs)were 83%(20/24)and 94%(29/31)in Rh1 and Rh2, respectively, at day 7; these were significantly higher than the proportion in SHIV_SF162P3 stock(49%(27/55)). Viral diversity after infection increased with time whereas the proportion of sequences containing 25 PNGSs decreased and sequences containing 27 PNGSs gradually increased. In Rh1, the percentage of sequences containing 27 PNGSs increased to 29% at day 28 and reached 35% at day 77 in Rh2. By analyzing the number of PNGSs in the V1-V5 regions, we found that PNGS variation mainly occurred in the V4 loop. Compared with sequences containing 27 PNGSs, a seven amino acid(TWNNTIG)deletion was found in the V4 loop, which resulted in a loss of two PNGSs at positions 392 and 396. Conclusion: Low glycosylation of the SHIV_SF162P3 V4 loop may facilitate spread of the SHIV virus whereas viruses with highly glycosylated V4 loops showed replication advantages after infection.

Revealing potential long non-coding RNA biomarkers in lung adenocarcinoma using long non-coding RNA-mediated competitive endogenous RNA network

In our study, we aimed to reveal potential long non-coding RNAs (lncRNA) biomarkers in lung adenocarcinoma (LAD) using lncRNA-mediated competing endogenous RNAs (ceRNAs) network (LMCN). Competing lncRNA-mRNA interactions were identified using the hypergeometric test. Co-expression analysis for the competing lncRNA-mRNA interactions was implemented, and relying on the weight value >0.8, a highly competitive LMCN was further constructed. Degree distribution, betweenness and closeness for LMCN were carried out to analyze the network structure. Functional analyses of mRNAs in LMCN were carried out to further explore the biological functions of lncRNAs. Biclique algorithm was utilized to extract competing modules from the LMCN. Finally, we verified our findings in an independent sample set using qRT-PCR. Based on degrees >60, we identified 4 hubs, including DLEU2, SNHG12, HCP5, and LINC00472. Furthermore, 2 competing modules were identified, and LINC00472 in module 1 functioned as a hub in both LMCN and module. Functional implications of lncRNAs demonstrated that lncRNAs were related to histone modification, negative regulation of cell cycle, neuroactive ligand-receptor interaction, and regulation of actin cytoskeleton. qRT-PCR results demonstrated that lncRNAs LINC00472, and HCP5 were down-regulated in LAD tissues, while the expression level of SNHG12 was up-regulated in LAD tissues. Our study sheds novel light on the roles of lncRNA-related ceRNA network in LAD and facilitates the detection of potential lncRNA biomarkers for LAD diagnosis and treatment. Remarkably, in our study, LINC00472, HCP5, and SNHG12 might be potential biomarkers for LAD management.

[An analysis of four cases of misdiagnosed primary lymphocytic hypophysitis]

To improve the differential diagnosis of sellar region mass, 4 cases with sellar mass and misdiagnosed as lymphocytic hypophysitis (LYH) were reviewed retrospectively.The 4 patients (2 male and 2 female) aged 20-60 years old were all presented with symptoms of headache, polydipsia and polyuria.Biochemical studies confirmed the diagnoses of central diabetes insipidus and hypopituitarism.Head MRI scans showed LYH like image for all the cases, and, thus, high dose methylprednisolone pulse therapy (HDMPT) was applied to the patients.Their symptoms deteriorated and the sellar mass enlarged after a short period of partial improvement.Operations were performed in all the patients.Histology study showed craniopharyngioma with abscess, primary abscess, secondary hypophysitis caused by Wegener's granulomatosis, and germinoma with secondary hypophysitis, respectively.In conclusion, surgery or biopsy is necessary for those who presented with sellar region mass and was suspected to be with LYH, but with poor response or even worse after HDMPT.