[Role of MAIT cells in immunity against Mycobacterium tuberculosis]

Mucosal-associated invariant T cells (MAIT cells) are a class of innate immune-like T cells that are widely distributed in the human body. During infection, antigens such as vitamin B metabolites synthesized by microorganisms are presented to MAIT cells by MR1 (major histocompatibility complex class Ⅰ-like molecule), and MAIT cells are activated and exert antibacterial, antiviral, anticancer and tissue repair effects by releasing cytokines and cytotoxic molecules. Animal and in vitro studies have shown that the number of MAIT cells in the peripheral blood of patients with active tuberculosis is reduced and the cells exhibit a functional exhaustion phenotype. MAIT cells are activated by Mycobacterium tuberculosis antigens and produce inflammatory cytokines such as TNF-α, IFN-γ and cytotoxic molecules such as granzyme B to exert anti-tuberculosis effects that are MR1-dependent and cytokine-dependent. In addition, MAIT cells can also act as a bridge between innate and acquired immunity by initiating a conventional T-cell response. Currently, there are also relevant experimental studies on vaccines and drugs targeting MAIT cells, which show great potential in the prevention and control of tuberculosis. In this article, we will review the discovery and grouping, development and activation of MAIT cells, their role in Mycobacterium tuberculosis infection, and their application in tuberculosis prevention and treatment, in order to provide new immunological targets for tuberculosis prevention and treatment.

Phylogeny, character evolution, and biogeography of the fern genus Bolbitis (Dryopteridaceae)

Bolbitis is a pantropical fern genus of Dryopteridaceae with ca. 80 species mainly in tropical Asia. Earlier studies confirmed the monophyly of Bolbitis when Mickelia is excluded and identified three major clades in Bolbitis. However, earlier studies are based on relatively small sampling and the majority of Asian species are not sampled. In this study, DNA sequences of three plastid markers of 169 accessions representing ca. 68 (85 % of total) species of Bolbitis in nine out of the 10 series recognized by Hennipman (1977), and 54 accessions representing the five remaining bolbitidoid genera are used to infer a global phylogeny with a focus on Asian species. The major results include: (1) Bolbitis is strongly supported as monophyletic; (2) species of Bolbitis are resolved into four major clades and their relationships are: the Malagasy/Mascarene clade is sister to the rest, followed by the African clade which is sister to the American clade + the Asian clade; (3) six well-supported subclades are identified in the most speciose Asian clade; (4) the free-veined Egenolfia is embedded in Bolbitis and is paraphyletic in relation to species with anastomosing venation; (5) three series sensu Hennipman (1977), B. ser. Alienae, B. ser. Egenolfianae, and B. ser. Heteroclitae, are paraphyletic or polyphyletic; (6) evolution of six morphological characters is analyzed and free venation is found to have evolved from anastomosing venation and reversed to free venation in Bolbitis; and (7) biogeographical implications are drawn and it is shown that a single recent dispersal from Asia resulted in continental disjunction of closely related ferns of Bolbitis between Africa and America.

[Diagnostic value of FCGR1B gene transcription level in active tuberculosis]

Objective: To investigate the diagnostic potential of Fc fragment of IgG receptor 1b gene (FCGR1B) transcription level in active tuberculosis. Methods: From February to September of 2018, we collected peripheral blood from patients with active tuberculosis, latent tuberculosis infection (LTBI), cured patients with tuberculosis, healthy people and patients with pneumonia in the Eighth Medical Center of PLA General Hospital. Peripheral blood mononuclear cells (PBMCs) were isolated for total RNA extraction and cDNA synthesis. The expression of FCGR1B mRNA in PBMCs was detected by quantitative real-time PCR (QPCR). Nonparametric test was used to compare the differential expression of FCGR1B mRNA between patients with active tuberculosis and control groups, and the relationships between FCGR1B mRNA expression and patient's illness condition and inflammatory indexes were analyzed by Correlation analysis. The potential of FCGR1B mRNA as a diagnostic marker for active tuberculosis was evaluated by receiver operating characteristic curve (ROC) analysis. Results: The expression of FCGR1B mRNA in PBMCs from patients with active tuberculosis was significantly increased when compared with non-tuberculosis controls, including individuals with LTBI, healthy people, cured patients with tuberculosis and patients with pneumonia (u=2 081, P<0.001). The expression of FCGR1B mRNA was higher in patients with tuberculosis who had more bacteria(H=12.35, P=0.015), and was correlated with the C-reactive protein (CRP) (r=0.30, P=0.008). ROC analysis showed that FCGR1B mRNA could distinguish active tuberculosis from non-tuberculosis with area under curve (AUC) of 0.849. The sensitivity and specificity were 71.43% and 84.17% respectively. The AUC of FCGR1B mRNA in distinguishing extra-pulmonary tuberculosis from controls was 0.906. The sensitivity and specificity were 84.62% and 91.89%, respectively. Conclusion: FCGR1B mRNA is a potential molecular marker for diagnosis of active tuberculosis.

[Regulatory effect of the zinc transporter Zip2 on cardiomyocyte mitochondrial respiration function after cardiac ischemia-reperfusion injury in mice]

The aim of the present study was to investigate the effect of zinc transporter Zip2 (SLC39A2) on mitochondrial respiration during myocardial ischemia/reperfusion (I/R) and the underlying mechanisms. An in vivo myocardial I/R model was established in mice by ligation of left anterior descending coronary artery. Cardiac zinc concentration was measured by inductively coupled plasma-optical emission spectrometer (ICP-OES), and the mitochondrial respiratory function and oxidative phosphorylation were determined by high-resolution respirometry (Oxygraph-2K). The phosphorylation levels of STAT3 and ERK in myocardial tissue were detected by Western blot. The results showed that, compared with the sham group, cardiac zinc concentration in myocardium was decreased in wild-type mice and further reduced in Zip2 knockout mice after I/R. Mitochondrial respiratory control rate (RCR) and oxidative phosphorylation were decreased in Zip2 knockout mice and worsened by I/R. Phosphorylation levels of STAT3 (Ser⁷²⁷) and ERK were significantly decreased in Zip2 knockout mice after I/R. In I/R myocardial tissue, STAT3 overexpression significantly improved the mitochondrial respiratory function, while STAT3 dominant negative mutant (STAT3 S727A) inhibited mitochondrial respiratory function. Moreover, the impairment of mitochondrial function by Zip2 knockout was reversed by STAT3 overexpression. These results suggest that Zip2 regulates mitochondrial respiration via phosphorylation of STAT3 during myocardial I/R, which may represent the underlying mechanism of Zip2 cardioprotection against I/R injury.

Curing hemophilia A by NHEJ-mediated ectopic F8 insertion in the mouse

BACKGROUND

Hemophilia A, a bleeding disorder resulting from F8 mutations, can only be cured by gene therapy. A promising strategy is CRISPR-Cas9-mediated precise insertion of F8 in hepatocytes at highly expressed gene loci, such as albumin (Alb). Unfortunately, the precise in vivo integration efficiency of a long insert is very low (~ 0.1%).

RESULTS

We report that the use of a double-cut donor leads to a 10- to 20-fold increase in liver editing efficiency, thereby completely reconstituting serum F8 activity in a mouse model of hemophilia A after hydrodynamic injection of Cas9-sgAlb and B domain-deleted (BDD) F8 donor plasmids. We find that the integration of a double-cut donor at the Alb locus in mouse liver is mainly through non-homologous end joining (NHEJ)-mediated knock-in. We then target BDDF8 to multiple sites on introns 11 and 13 and find that NHEJ-mediated insertion of BDDF8 restores hemostasis. Finally, using 3 AAV8 vectors to deliver genome editing components, including Cas9, sgRNA, and BDDF8 donor, we observe the same therapeutic effects. A follow-up of 100 mice over 1 year shows no adverse effects.

CONCLUSIONS

These findings lay the foundation for curing hemophilia A by NHEJ knock-in of BDDF8 at Alb introns after AAV-mediated delivery of editing components.

Antimalarial drug artemisinin extenuates amyloidogenesis and neuroinflammation in APPswe/PS1dE9 transgenic mice via inhibition of nuclear factor-κB and NLRP3 inflammasome activation

BACKGROUND

The activation of nuclear factor-kappa B (NF-κB) and NLRP3 inflammasome is involved in neuroinflammation, which is closely linked to Alzheimer's disease (AD). In vivo and in vitro studies have suggested that artemisinin shows antiinflammatory effects in inflammation-related diseases. However, the impacts of artemisinin on AD have not been investigated.

AIMS

In this study, 5-month-old APPswe/PS1dE9 transgenic mice were treated daily with 40 mg/kg artemisinin for 30 days by intraperitoneal injection to evaluate the effects of artemisinin on AD.

RESULTS

We found that artemisinin treatment (1) decreased neuritic plaque burden; (2) did not alter Aβ transport across the blood-brain barrier; (3) regulated APP processing via inhibiting β-secretase activity; (4) inhibited NF-κB activity and NALP3 inflammasome activation in APPswe/PS1dE9 double transgenic mice.

CONCLUSIONS

The in vivo study clearly demonstrates that artemisinin has protective effects on AD pathology due to its effects on suppressing NF-κB activity and NALP3 inflammasome activation. Our study suggests that targeting NF-κB activity and NALP3 inflammasome activation offers a valuable intervention for AD.

All-metal self-supported THz metamaterial--the meta-foil

Modern metamaterials face functional constraints as they are commonly embedded in or deposited on dielectric materials. We provide a new solution by microfabricating a completely free-standing all-metal self-supported metamaterial. Using upright S-string architecture with the distinctive feature of metallic transverse interconnects, we form a locally stiff, globally flexible space-grid. Infrared Fourier transform interferometry reveals the typical double-peak structure of a magnetically excited left-handed and an electrically excited right-handed pass-band that is maintained under strong bending and heating, and is sensitive to dielectrics. Exploiting UV/X-ray lithography and ultimately plastic moulding, meta-foils can be mass manufactured cost-effectively to serve as optical elements.

Free-standing THz electromagnetic metamaterials

Using micromanufactured S-shaped gold strings suspended in free space by means of window-frames, we experimentally demonstrate an electromagnetic meta-material (EM(3)) in which the metallic structures are no longer embedded in matrices or deposited on substrates such that the response is solely determined by the geometrical parameters and the properties of the metal. Two carefully aligned and assembled window-frames form a bi-layer chip that exhibits 2D left-handed pass-bands corresponding to two different magnetic resonant loops in the range of 1.4 to 2.2 THz as characterized by Fourier transform interferometry and numerical simulation. Chips have a comparably large useful area of 56 mm(2). Our results are a step towards providing EM(3) that fulfill the common notions of a material.

The prediction of variability occurring in fluidized bed coating equipment. II. The role of nonuniform particle coverage as particles pass through the spray zone

The purpose of this work was to evaluate the relative importance of particle circulation and particle-to-particle mass coating distribution on the overall mass coating distribution obtained in a Wurster process. A series of batch coating experiments was carried out over a range of operating conditions, in order to evaluate the particle-to-particle variation in the mass distribution of coating material deposited during batch coating operations. Results showed that the major component of variance was due to the variation in the amount of coating received per particle per pass through the spray zone. The variation in the number of times a particle passed through the spray zone was considerably less important. Two models were developed to explain the results of the experimental program. The first model categorized particles moving through the spray zone as either receiving coating or not. Thus, the distribution of coating material per particle per pass is described by a Bernoulli probability distribution. Using this picture of the spray process, the number of particles receiving coating during any given pass through the spray zone was found to vary between 2 and 6%. A second model was developed to explain the major cause of variation. This model explains the variation in terms of the hindering or sheltering effect that particles close to the source of the spray have on particles farther away. Although the agreement of model predictions with experimental results is only fair, it is believed that this model captures the main cause of particle-to-particle variation occurring in batch coating operations and thus is the first model to explain this phenomenon.

The prediction of variability occurring in fluidized bed coating equipment. I. The measurement of particle circulation rates in a bottom-spray fluidized bed coater

The purpose of this work was to investigate the effect that changes in design and process variables had on the movement of particles around a fluidized bed coating apparatus. To measure the mean and variance of the particle cycle time distribution (CTD), the number of passages taken by a magnetic tracer particle through the spray zone was measured by a detector coil wound around the partition. The reproducibility of the measurement technique was tested by taking repeated measurements of the tracer particle movement, using similar bed operating conditions, and the method was found to give reproducible results. A series of experiments was carried out by varying operating conditions such as the partition gap, fluidizing air rate, and partition diameter and length, and measuring the change in the rate at which the tracer particle circulated in the coating device. The results of the experiments showed that, over the range of parameters tested in this work, the partition gap had the strongest influence on the rate of particle circulation. Moreover, for the 6-in.-diameter Wurster process used in the current work, the mean circulation time for the 1.1-mm-diameter Nu-Pareil particles was found to vary over the range of 2.2-10.4 sec. In addition, the mean and standard deviation of the CTD could be linearly correlated over a wide range of operating conditions, with a correlation coefficient of 0.80. Finally, an estimate of the variability in mass coating uniformity was made based on the results from the cycle time distributions. It was concluded that the effect of variability in the CTD could account for only a small fraction of the variability in the observed mass coating distribution.

[Clinical study on niaodujing in treating chronic renal failure]

One hundred and five chronic renal failure patients were divided randomly into two groups, 75 cases of Niaodujing (NDJ) treatment group and 30 cases of control group treated with aldehyde coated oxystarch. The effects were compared between two groups and within the same group before and after the entry. Results indicated that the total effective rate and markely effecive rate of NDJ group (74.1% and 44.0%) were better than those of the control group (56.6% and 23.3%) respectively (P < 0.05). The serum creatinine, blood urea nitrogen and middle molecular substance were decreased and creatinine clearance rate was increased significantly after NDJ treatment as compared with before treatment (P < 0.05-0.01). In comparison of two groups, the decrement of creatinine clearance rate and middle molecular substance and the increment of creatinine in NDJ group were higher than that in control group (P < 0.05-0.01). NDJ was especially effective in patients with azotemia or early renal failure.

[Protection of common peony from scarab damages]

The key to the protection of common peony from insect pests in the field is to control the damage done by Holotrichia oblita. An experimental study has been carried out on the prevention of adult pests in the field as well as on the prevention of pest larvae before planting and throughout the growing period of common peony. As a result a technological program for this particular pest prevention and elimination is proposed.

Automated measurement method for 360 degrees profilometry of 3-D diffuse objects

An automated measurement method for 360 degrees surface topography of 3-D diffuse objects is presented. The method is based on the simple principle of triangulation with structured illumination. The geometric specifications of the structured light module used in the system are analyzed on a computer. Using an advantageous data acquisition schedule, high data acquisition rates and measuring accuracy can be achieved. The system comprises a structured lighting projector, a 2-D detector array, and a microcomputer for control and processing. Experimental results for 3-D objects are offered.

Red plaque formation of Coxiella burnetii and reduction assay by monoclonal antibodies

A red plaque technique for C. burnetii which utilizes primary chicken embryo cells, is described. Red plaques could be consistently detected as early as 6 days, usually 8 days post inoculation (p.i.), reflecting that C. burnetii proliferated within the phagolysosomes of host cells. Incubation with phase II monoclonal antibodies or inactivated immune sera containing phase I and phase II antibodies or phase II antibodies only, markedly reduced phase II C. burnetii red plaques. On the other hand, red plaques from phase I organisms increased several times when phase I cells were mixed with phase I monoclonal antibodies or inactivated immune sera containing phase I and phase II antibodies. By indirect red plaque reduction assay red plaque production by phase II cells could be reduced as well.

[Transmission of Anhui fritillary rot by Rhizoglyphus robini Clapareded and its control]

The bulb mite is the main transmitter of anhui fritillary rot, and damages the fritillary seriously. Control of this mite can be effected satisfactorily by proper rotation of crops, exposure of ploughed fields to the sun, selection of healthy bulbs for planting and treatment of soil and bulbs with pesticides.

Early vascular grafting to prevent upper extremity necrosis after electrical burns: II. Experience with wound infection management

Since May 1972, vein grafts have been used to restore circulation in electrical injuries of the upper extremity when the wrist has been the centre of electrical injury associated with obstructed blood supply. Saphenous vein grafts were used in fifteen limbs in fourteen patients where electrical injuries at the wrist threatened complete loss of the hand. Ten of the hands were free of necrosis with motion basically recovered. The other four cases (five limbs) failed in operation for various reasons, resulting in forearm amputations. Clinical practice showed that successful operations depend upon whether secondary infection is effectively controlled, particularly in those who were brought to the hospital late with wound infection and gangrene of the fingers. This paper reviews the measures for controlling postoperative infections in vascular grafting to restore blood flow at the wrist, and the clinical experience gained in treating these patients (six injured limbs of six cases), and preventing amputation. We hope the method could be improved and its use broadened.