A Mini-review for the Application of Bacterial Cellulose-based Composites

Countries are duly focusing more on biomass resources because of the increasing oil crisis.Owing to their excellent properties,such as natural characteristics,good mechanical performance,and outstanding chemical properties,cellulose-based materials are highly valued as promising bioderived nanomaterials,especially bacterial cellulose(BC).The main advantage lies in eliminating the problem of removing lignin and hemicellulose from woody cellulose.Moreover,the use of BC reduces the consumption of wood,the excessive use of which aggravates global warming.Herein,we summarize the applications of BC composites in filter,medical,and conductive materials,and other fields.This review contributes to further expand the applications of this renewable polymer.

Growth Inhibiton of Human Breast Cancer Cell Line MDA-MB-231 by Rosiglitazone through Activation of PPARγ

OBJECTIVE To investigate the anti-proliferative effect ofrosiglitazone and its relationship to peroxisome proliferator-activated receptor γ(PPARγ)in human breast cancer cell lineMDA-MB-231 and evaluate the potential application value ofrosiglitazone for breast cancer therapy.METHODS The cytostatic effect of rosiglitazone on MDA-MB-231 cells was measured by the MTT assay.Cell-cyclekinetics was assessed by flow cytometry.Apoptotic cells weredetermined by the TUNEL assay.MDA-MB-231 cells weretreated with rosiglitazone or in combination with the PPARγantagonist GW9662 to investigate the effect of rosiglitazone on cellproliferation and its relationship to PPARγ.RESULTS The results showed that rosiglitazone could inhibitgrowth of MDA-MB-231 cells in a dose- and time-dependentmanner with an IC_(50)value of 5.2μmol/L at 24 h after the drugwas added into the culture.Cell cycle analysis showed that thepercentage of G_0/G_1 phase cells increased,S phase cells decreased,and cells were arrested in G_1 phase with increasing concentrationsof rosiglitazone.Detectable signs of apoptotic cell death caused byrosiglitazone occurred at a concentration of 100 μmol/L and theapoptotic rate was (18±3)%.PPARγ selective antagonist GW9662could partially reverse the inhibitory effect of rosiglitazone onproliferation of MDA-MB-231 cells.CONCLUSION It was concluded that rosiglitazone can inhibitgrowth of MDA-MB-231 cells via PPARγ activation and a highconcentration of rosiglitazone can also induce MDA-MB-231 cellapoptosis.These results suggest that PPARγ represents a putativemolecular target for chemopreventive therapy and rosiglitazonemay be effective in the treatment of breast cancer.

生长后热事件对生长环带石榴石的影响及其在变质作用p-t历史计算中的意义

为了研究生长后热历史对生长环带矿物的影响,我们提出了一个简单的扩散模式。在这个模式中把矿物作为化学封闭体系,并把任何热历史的影响转换成一个实质性参数。研究表明环带矿物在变质p-t历史计算中的有效性取决于矿物颗粒的大小和生长后热历史。以石榴石为例,较大的石榴石(>1mm)可放心去使用,若石榴石颗粒<1mm,且形成温度相当的高绿片岩或低角闪岩相,则将得出严重错误的结果。所计算出的生长历史与真正生长历史的偏差可能大于100℃,尤其是石榴石生长历史的较早期部分偏差最大。

Discovering deaminases using AlphaFold2:a strategy to search for tool proteins for gene editing

A recent study by Huang et al.published in Cell reported the application of AlphaFold2 to forecast the structures of deaminase proteins and cluster them based on structural similarity,creating a truncated Sdd that can be used as a cytosine base editor(CBE)to be integrated into a single adeno-associated virus(AAV)1 This ground-breaking study aided by the artificial intelligence system would largely broaden the utility of tool proteins for gene editing.

Collective cell migration: Implications for wound healing and cancer invasion

During embryonic morphogenesis, wound repair and cancer invasion, cells often migrate collectively via tight cell-cell junctions, a process named collective migration. During such migration, cells move as coherent groups, large cell sheets, strands or tubes rather than individually. One unexpected finding regarding collective cell migration is that being a "multicellular structure" enables cells to better respond to chemical and physical cues, when compared with isolated cells. This is important because epithelial cells heal wounds via the migration of large sheets of cells with tight intercellular connections. Recent studies have gained some mechanistic insights that will benefit the clinical understanding of wound healing in general. In this review, we will briefly introduce the role of collective cell migration in wound healing, regeneration and cancer invasion and discuss its underlying mechanisms as well as implications for wound healing.

Regulatory factors of mesenchymal stem cell migration into injured tissues and their signal transduction mechanisms

Adult stem cells hold great promise for wound healing and tissue regeneration.Mesenchymal stem cells(MSCs),for example,have been shown to play a role in tissue repair.Research has shown that endogenous bone marrow MSCs or exogenously delivered MSCs migrate to the sites of injury and participate in the repair process.The precise mechanisms underlying migration of MSCs into the injured tissue are still not fully understood,although multiple signaling pathways and molecules were reported,including both chemoattractive factors and endogenous electric fields at wounds.This review will briefly summarize the regulatory facors and signaling transduction pathways involved in migration of MSCs.A better understanding of the molecular mechanisms involved in the migration of MSCs will help us to develop new stem cell-based therapeutic strategies in regenerative medicine.

Solvability and thermal response of cellulose with different crystal configurations

Cellulose is a biodegradable and renewable natural material that it is naturally resistant to breaking and modification. Moreover, the crystalline structure of cellulose is a major factor restricting its industrial utilization. In this study, cellulose polymorphs were prepared from natural cellulose, and their solvability and thermal response were investigated. Using liquid- and solid-state NMR signals, the distinct types and dissolving states of cellulose polymorphs were identified. The thermal behavior of the polymorphic forms of cellulose-d was also evaluated, and cellulose Ⅱ exhibited the poorest thermal stability and a unique exothermic reaction.

The current surgical treatment of pancreatic neuroendocrine neoplasms in China: a national wide cross-sectional study

Objective:The aim of this study is to investigate the current status of the diagnosis and treatment of patients with pancreatic neuroendocrine neoplasms(pNENs)undergoing surgery in China.Methods:This is a multicenter cross-sectional study performed in China.Data from patients with pNENs undergoing surgery at 33 high-volume medical centers,where the number of pancreatectomies exceeds 20 cases per year,were collected and analyzed between March 1,2016 and February 28,2017.Results:In total,392 patients with pNENs were enrolled.The male to female ratio was 1.4.The majority of patients were aged between 40 and 70 years.65.6%of the patients had non-functional tumors.Among those with functional tumors,the percentages of insulinomas,gastrinomas,glucagonomas,and vasoactive intestinal peptide-secreting tumors were 94.8%,1.5%,2.2%,and 1.5%,respectively.Multidisciplinary team(MDT)discussion was conducted for 39.0%of the patients.Minimally invasive surgery was performed on 31.1%of the 392 patients.The incidence of grade B/C pancreatic fistula formation was 4.4%.A total of 89.0%of the surgeries achieved R0 resection,and 41.6%of the tumors were well differentiated.Lymph node metastasis was present in 8.9%of the patients.The percentages of patients with grades G1,G2,and G3 disease were 49.2%,45.7%,and 5.1%,respectively.Conclusion:This multicenter cross-sectional study systematically presents the current status of the diagnosis and treatment of patients with pNENs undergoing surgery in China.MDT consultation for pNENs has not been widely implemented in China.Although the incidence of surgical complications is relatively low,minimally invasive procedures should be further promoted.This study shows us how to improve the outcomes of these patients.

The current surgical treatment of pancreatic cancer in China: a national wide cross-sectional study

Objective: The aim of this study is to investigate the current status of pancreatic cancer patients undoing surgical treatment in China and to find ways to improve the survival of these patients in the future. Methods: This study is a national, multicenter, cross-sectional study in China. Information regarding pancreatic cancer patients undergoing surgical treatment from 34 high-volume tertiary IIIA level hospitals was collected and analyzed from the March 1, 2016 to the February 28, 2017. Results: In total, 2200 pancreatic cancer patients were enrolled from 34 tertiary IIIA level hospitals in 16 provinces across China. The male-to-female ratio was 1.5. More than 80% of the patients were between 50 and 70 years old. The top 4 symptoms were epigastric discomfort, abdominal pain, jaundice, and weight loss. Carbohydrate antigen 19-9 and carcinoembryonic antigen were elevated in 70.9% and 27.1% of patients, respectively. A multidisciplinary team (MDT) discussion was carried out for 35.0% of patients before surgery. The proportion of minimally invasive pancreatic surgeries was approximately 20%. A total of 83.4% of the operations achieved R0 resection, and the incidence of grade 3/4 postoperative complications was 7.7%. Only 13.4% of the patients received postoperative adjuvant chemotherapy. The percentage of pathological stage I tumors was only 24.5%. Conclusion: The majority of pancreatic cancer patients undergoing surgical resection in China are in an advanced stage. The MDT consultations for pancreatic cancer have not been widely carried out. R0 resection has been achieved in most cases, with relatively low incidence of serious complications, but minimally invasive pancreatic surgery should be further promoted. The application of postoperative chemotherapy remains low. This national, multicentre, cross-sectional study comprehensively presents the current status of pancreatic cancer patients undergoing surgical treatment and shows the road to improve survival of these patients in the future.

PDGFR kinase inhibitor protects against septic death via regulation of BTLA

Sepsis,defined as life-threatening organ failure caused by a dysregulated host response to severe infection,is a major cause of death among intensive care unit patients.Therapies targeting on immunomodulatory is a new research field in sepsis treatment.B-and T-lymphocyte attenuator(BTLA)is an inhibitory costimulatory factor molecule of B and T lymphocytes.Studies have shown that elevated expression of BTLA in lymphocytes can reduce mortality in sepsis,but its regulatory compounds and the underlying mechanism remains to be elucidated.Here,we show that treatment with CP-673451 significantly decreases mortality of septic mouse.CP-673451 is a PDGFR kinase inhibitor which can promote the expression of BTLA,inhibit the release of chemokines such as CXCL13,and reduce first the chemotaxis of B cells to the peripheral blood and vital organs.CP-673451 also inhibits both the release of cytokines and chemokines such as IL-1β,IL-6,IL-10,TNF-α,CCL1,CCL2 and CCL7 and reduces both the chemotactic ability of T cells.This suggests that CP-673451 may prevent septic death by inhibiting lymphocyte chemotaxis and alleviating“cytokine storm”.In conclusion,our study provides a new therapeutic target and an effective compound for sepsis treatment.

Stem cell niches and endogenous electric fields in tissue repair

Adult stem cells are responsible for homeostasis and repair of many tissues.Endogenous adult stem cells reside in certain regions of organs,known as the stem cell niche,which is recognized to have an important role in regulating tissue maintenance and repair.In wound healing and tissue repair,stem cells are mobilized and recruited to the site of wound,and participate in the repair process.Many regulatory factors are involved in the stem cell-based repair process,including stem cell niches and endogenous wound electric fields,which are present at wound tissues and proved to be important in guiding wound healing.Here we briefly review the role of stem cell niches and endogenous electric fields in tissue repair,and hypothesize that endogenous electric fields become part of stem cell niche in the wound site.

Applications and challenges of CRISPR-Cas gene-editing to disease treatment in clinics

Clustered regularly interspaced short palindromic repeats(CRISPR)-associated systems(Cas)are efficient tools for targeting specific genes for laboratory research,agricultural engineering,biotechnology,and human disease treatment.Cas9,by far the most extensively used gene-editing nuclease,has shown great promise for the treatment of hereditary diseases,viral infection,cancers,and so on.Recent reports have revealed that some other types of CRISPR-Cas systems may also have surprising potential to join the fray as gene-editing tools for various applications.Despite the rapid progress in basic research and clinical tests,some underlying problems present continuous,significant challenges,such as editing efficiency,relative difficulty in delivery,off-target effects,immunogenicity,etc.This article summarizes the applications of CRISPR-Cas from bench to bedside and highlights the current obstacles that may limit the usage of CRISPR-Cas systems as gene-editing toolkits in precision medicine and offer some viewpoints that may help to tackle these challenges and facilitate technical development.CRISPR-Cas systems,as a powerful gene-editing approach,will offer great hopes in clinical treatments for many individuals with currently incurable diseases.

CRISPR base editor treats premature-aging syndrome

A recent paper published in Nature by Koblan et al.reported the use of CRISPR-mediated adenine base editor(ABE)to repair mutations of the Hutchinson-Gilford progeria syndrome(HGPS or progeria),attenuate symptoms,and extend lifespan of mice(Fig.1),representing a major advance in design of treatments for human accelerated-ageing disorders and potentially other genetic diseases.