A Blockchain-Based Access Control Scheme for Reputation Value Attributes of the Internet of Things

The Internet of Things(IoT)access controlmechanism may encounter security issues such as single point of failure and data tampering.To address these issues,a blockchain-based IoT reputation value attribute access control scheme is proposed.Firstly,writing the reputation value as an attribute into the access control policy,and then deploying the access control policy in the smart contract of the blockchain system can enable the system to provide more fine-grained access control;Secondly,storing a large amount of resources fromthe Internet of Things in Inter Planetary File System(IPFS)to improve system throughput;Finally,map resource access operations to qualification tokens to improve the performance of the access control system.Complete simulation experiments based on the Hyperledger Fabric platform.Fromthe simulation experimental results,it can be seen that the access control system can achieve more fine-grained and dynamic access control while maintaining high throughput and low time delay,providing sufficient reliability and security for access control of IoT devices.

An Energy Trading Method Based on Alliance Blockchain and Multi-Signature

Blockchain,known for its secure encrypted ledger,has garnered attention in financial and data transfer realms,including the field of energy trading.However,the decentralized nature and identity anonymity of user nodes raise uncertainties in energy transactions.The broadcast consensus authentication slows transaction speeds,and frequent single-point transactions in multi-node settings pose key exposure risks without protective measures during user signing.To address these,an alliance blockchain scheme is proposed,reducing the resource-intensive identity verification among nodes.It integrates multi-signature functionality to fortify user resources and transac-tion security.A novel multi-signature process within this framework involves neutral nodes established through central nodes.These neutral nodes participate in multi-signature’s signing and verification,ensuring user identity and transaction content privacy.Reducing interactions among user nodes enhances transaction efficiency by minimizing communication overhead during verification and consensus stages.Rigorous assessments on reliability and operational speed highlight superior security performance,resilient against conventional attack vectors.Simulation shows that compared to traditional solutions,this scheme has advantages in terms of running speed.In conclusion,the alliance blockchain framework introduces a novel approach to tackle blockchain’s limitations in energy transactions.The integrated multi-signature process,involving neutral nodes,significantly enhances security and privacy.The scheme’s efficiency,validated through analytical assessments and simulations,indicates robustness against security threats and improved transactional speeds.This research underscores the potential for improved security and efficiency in blockchain-enabled energy trading systems.

Long-term follow-up of the effects of fecal microbiota transplantation in combination with soluble dietary fiber as a therapeutic regimen in slow transit constipation

As some studies have reported that strategies targeting the gut microbiota such as fecal microbiota transplantation(FMT) with or without other microecological therapy might have efficacy in treating slow transit constipation(STC), we conducted a singlecenter, open-label trial to study the long-term effect of FMT combined with soluble dietary fiber(pectin) on STC. Thirty-one adult patients with STC were enrolled into the trial. Patients received 6-day FMT procedures repeatedly for the first 3 months and soluble dietary fiber(pectin) daily during the follow-up. The rate of clinical remission and improvement, stool consistency, the Wexner constipation scale, and assessment of constipation-related symptoms were evaluated at week 4 and 1 year later. The clinical remission and improvement rates at week 4 were 69.0%(20/29) and 75.9%(22/29), respectively. At the end of the study,48.3%(14/29) of patients continued to have at least three complete spontaneous bowel movements per week and 58.6%(17/29)of patients showed clinical improvements. Stool consistency, the Wexner constipation scale, and constipation symptoms improved both at short-term and long-term follow-up. The results indicated that FMT in combination with soluble dietary fiber(pectin) had both short-term and long-term efficacy in treating STC.

Outcomes and prognostic factors of fecal microbiota transplantation in patients with slow transit constipation:results from a prospective study with long-term follow-up

Background and aim:Gutmicrobiotamay contribute to regulate colonicmotility,which is involved in the etiology of constipation.Fecalmicrobiota transplantation(FMT)has been demonstrated to restore intestinal homeostasis.The aimof this study was to evaluate the clinical outcomes and prognostic factors of FMT for the treatment of slow transit constipation(STC).Methods:Fifty-two patients with STC received standardized FMT and were followed up for 6 months.Bowel habit,colonic transit time,constipation-related symptoms(PAC-SYM score),quality of life(PAC-QOL score),treatment satisfaction scores and adverse events were monitored.The primary efficacy endpoint was the proportion of patients having on average three or more complete spontaneous bowel movements(CSBMs)per week.Results:The primary efficacy endpoint was achieved in 50.0%,38.5%and 32.7%of patients over week intervals 3–4,9–12 and 21–24,respectively(P<0.01 for all comparisons).Significant improvements were also observed in other bowel movement assessments,colonic transit time,constipation-related symptoms and quality of life;but all improvements diminished at weeks 12 and 24.Incompleteness of evacuation served as the only factor associated with efficacy.No serious treatmentrelated adverse events were observed.Conclusion:This study suggested FMT was effective and safe for STC,while a late loss of efficacy was also observed.A lower degree of sensation of incompleteness predicted a better outcome.

Structural basis of Zika virus helicase in recognizing its substrates

The recent explosive outbreak of Zika virus （ZlKV） infection has been reported in South and Central America and the Caribbean. Neonatal microcephaly associated with ZIKV infection has already caused a public health emergency of international concern. No specific vaccines or drugs are currently available to treat ZIKV infection. The ZIKV helicase, which plays a pivotal role in viral RNA replication, is an attractive tar- get for therapy. We determined the crystal structures of ZIKV helicase-ATP-Mnz＋ and ZlKV helicase-RNA. This is the first structure of any flavivirus helicase bound to ATP. Comparisons with related flavivirus helicases have shown that although the critical P-loop in the active site has variable conformations among different species, it adopts an identical mode to recognize ATPIMn2＋. The structure of ZlKV helicase-RNA has revealed that upon RNA binding, rotations of the motor domains can cause significant conformational changes. Strikingly, although ZlKV and dengue virus （DENV） apo-helicases share conserved residues for RNA binding, their different manners of motor domain rotations result in distinct individual modes for RNA recognition. It suggests that flavivirus helicases could have evolved a conserved engine to convert chemical energy from nucleoside triphosphate to mechanical energy for RNA unwinding, but different motor domain rotations result in variable RNA recognition modes to adapt to individual viral replication.

Fecal microbiota transplantation: standardization or diversification?

Call for standardization of fecal microbiota transplantation(FMT)The gut microbiota plays an important role in human health and disease.Dysbiosis is often recognized in patients with diseases of the digestive and other systems(Blaser,2019;Li et al.,2018b;Qin et al.,2018).FMT refers to the administration of fecal material containing distal gut microbiota from a healthy person(donor)to a patient(recipient)to restore the gut microecology of the recipient(Kelly et al.,2015).Clinical guidelines have strongly recommended FMT for the treatment of relapsed or refractory Clostridium difficile infection(CDI)(Mullish et al.,2018).FMT has also shown potential clinical benefits in many other diseases related to dysbiosis,including inflammatory bowel disease(IBD),irritable bowel syndrome(IBS),functional constipation(FC),liver diseases,metabolic syndrome,autism,and cancer(Huang et al.,2018;Li et al.,2018a;Zhang et al.,2018).Because of its broad curative potential,FMT has become a topic of great interest.More than 3,000 published articles have reported treatment of different diseases with FMT,and over 380 FMT trials have been registered on the ClinicalTrials.gov website.

Discovery of the first macrolide antibiotic binding protein in Mycobacterium tuberculosis： a new antibiotic resistance drug target

Dear Editor The prevalence of multidrug-resistant Mycobacterium tuberculosis （M. tuberculosis） is an increasing problem worldwide （Zumla et al., 2013; Dong et al., 2015）. According to a 2014 World Health Organization （WHO） report, 480,000 individuals world-wide .developed multidrug-resistant tuber- culosis （MDR-TB） and more than 100 countries have cases of extensively drug-resistant tuberculosis （XDR-TB）. Com- pared with drug-susceptible TB, MDR-TB and XDR-TB require prolonged therapeutic treatment with a combination of a number of second-line drugs （Chen et al., 2013）. For patients where TB remains persistent despite prolonged therapy with second-line TB drugs, the add-on agents including bedaquiline and delamanid are recommended for salvage therapy （GUnther, 2014; WHO, 2014; Shim and Jo, 2013）.

Fecal microbiota transplantation in clinical practice:Present controversies and future prospects

The gut microbiota,serving as the only“organ”that humans can share,has been extensively applied in the treatment of various intestinal and extraintestinal diseases through fecal microbiota transplantation(FMT)technology.By optimizing the donor selection strategy,FMT exhibited the highest effectiveness(more than 90%)in treating acute intestinal inflammations,such as recurrent Clostridium difficile infection.However,the efficacy diminishes when addressing intestinal functional diseases(more than 60%),chronic intestinal inflammations or organic diseases(less than 60%),and extraintestinal diseases,particularly those lacking any gastrointestinal symptoms(less than 50%).Ongoing efforts to enhance the therapeutic response of FMT across diverse diseases represent a central focus of current clinical research.This review concentrates on donor selection,recipient management,precise donor-recipient matching,antagonistic mechanism of native bacteria to transplanted bacteria,and targeted treatment strategies for different diseases,with the aim of providing practical strategies to improve the clinical efficacy of FMT.