RESUMEN

The box tree moth (BTM), Cydalima perspectalis Walker, is a pest that infests various plants within the Buxus genus. Although a specific parasitoid wasp species associated with the BTM has been observed in the Republic of Korea, no research on this species has been published. Here, we describe the fundamental morphological and biological characteristics of this parasitoid. We have identified the wasp as belonging to the genus Eriborus (Hymenoptera: Ichneumonidae: Campopleginae). Eriborus sp. parasitizes within the living host body, with 1 wasp emerging from each host. The parasitism rate observed in collected BTM populations was 33.1%. The emergence rate was 87.1%, with all emerging adults being females, resulting in a sex ratio of 0. The pupal period avg 9.5 days, and the adult lifespan avg 10.5 days. Eriborus sp. parasitized BTM larvae from the first to the fourth instar and reproduced by thelytokous parthenogenesis. Eriborus sp. exhibited morphological differences compared with previously reported Eriborus species in Korea, particularly in the length of the ovipositor sheath. Additionally, the proportion of the highest similarity in nucleotide sequences of mitochondrial cytochrome oxidase I DNA was only 94.53%, rendering species identification using GenBank's mt cytochrome c oxidase 1 DNA sequences unfeasible. These data suggest that Eriborus sp. could be used as a biological control agent for managing BTM infestations.

Asunto(s)

RESUMEN

Purpose: To analyze and review the progress of glucose metabolism-based molecular imaging in detecting tumors to guide clinicians for new management strategies. Summary: When metabolic abnormalities occur, termed the Warburg effect, it simultaneously enables excessive cell proliferation and inhibits cell apoptosis. Molecular imaging technology combines molecular biology and cell probe technology to visualize, characterize, and quantify processes at cellular and subcellular levels in vivo. Modern instruments, including molecular biochemistry, data processing, nanotechnology, and image processing, use molecular probes to perform real-time, non-invasive imaging of molecular and cellular events in living organisms. Conclusion: Molecular imaging is a non-invasive method for live detection, dynamic observation, and quantitative assessment of tumor glucose metabolism. It enables in-depth examination of the connection between the tumor microenvironment and tumor growth, providing a reliable assessment technique for scientific and clinical research. This new technique will facilitate the translation of fundamental research into clinical practice.

RESUMEN

【Objective】 Escherichia coli phage (ECP) and Staphylococcus aureus phage (SAP) isolated from sewage were used as research objects, and their biological characteristics were analyzed to provide new experimental materials for the application of phages. 【Methods】 ECP and SAP were purified and cultured by double-layer agar method. Then a series of biological characteristics of these two phages were preliminarily analyzed by electron microscope observation, optimal multiplicity of infection (MOI) test, one-step growth curve test, temperature, pH, chloroform and ultraviolet sensitivity tests, respectively. 【Results】 The results of biological characteristics showed that ECP and SAP were both virulent phages, belonging to myoviridac family. Their optimal MOI was 10-1, and they had strong resistance to ultraviolet light. The cleavage volume of ECP was 76.3 PFU/cell, while that of SAP was 8.3 PFU/cell. ECP had a wide range of temperature tolerance and could stably survive at 30-50 ℃, while SAP was more sensitive to temperature and could be completely inactivated at 50 ℃ for 1 h. ECP could maintain a good lysis activity in the range of pH 5-11, while SAP in the range of pH 6-9. ECP had strong resistance to chloroform and was non-membranous phage, while SAP was more sensitive to chloroform and was a membranous phage. 【Conclusion】 ECP and SAP are both virulent phages and have strong resistance to ultraviolet light. The lysability, temperature, pH, and chloroform tolerance of ECP are stronger than those of SAP.

RESUMEN

Coxsackievirus A6 (CVA6) is a key pathogen causing hand, foot and mouth disease (HFMD). However, there are currently no specific antiviral drugs or vaccines for treating infections caused by CVA6. In this study, human rhabdomyosarcoma (RD), African green monkey kidney (Vero), and human embryonic lung diploid fibroblast (KMB17) cells were used to isolate CVA6 from 327 anal swab and fecal samples obtained during HFMD monitoring between 2009 and 2017. The VP1 genes of the isolates were sequenced and genotyped, and the biological characteristics of the representative CVA6 strains were analyzed. A total of 37 CVA6 strains of the D3 gene subtypes were isolated from RD cells, all of which belonged to the epidemic strains in mainland China. Using the adaptive culture method, 10 KMB17 cell-adapted strains were obtained; however, no Vero cell-adapted strains were acquired. Among the KMB17 cell-adapted strains, only KYN-A1205 caused disease or partial death in suckling mice, and its virulence was stronger than its RD cell-adapted strain. The pathogenic KYN-A1205 strain caused strong tropism to the muscle tissue and led to pathological changes, including muscle necrosis and nuclear fragmentation in the forelimb and hindlimb. Sequence analysis demonstrated that the KYN-A1205 strain exhibited multiple amino acid mutations after KMB17 cell adaptation. Moreover, it showed strong pathogenicity, good immunogenicity and genetic stability, and could be used as an experimental CVA6 vaccine candidate.

Asunto(s)

RESUMEN

Salmonella is a widely distributed foodborne pathogen. The use of Salmonella phages as biocontrol agents has recently gained significant interest. Because the Salmonella genus has high diversity, efforts are necessary to identify lytic Salmonella phages focusing on different serovars. Here, five Salmonella phages were isolated from soil samples, and vB_SalP_TR2 was selected as a novel phage with high lytic potential against the host Salmonella serovar Albany, as well as other tested serovars, including Corvallis, Newport, Kottbus, and Istanbul. Morphological analyses demonstrated that phage vB_SalP_TR2 belongs to the Podoviridae family, with an icosahedral head (62 ± 0.5 nm in diameter and 60 ± 1 nm in length) and a short tail (35 ± 1 nm in length). The latent period and burst size of phage vB_SalP_TR2 was 15 min and 211 PFU/cell, respectively. It contained a linear dsDNA of 71,453 bp, and G + C content was 40.64%. Among 96 putative open reading frames detected, only 35 gene products were found in database searches, with no virulence or antibiotic resistance genes being identified. As a biological control agent, phage vB_SalP_TR2 exhibited a high temperature and pH tolerance. In vitro, it lysed most S. Albany after 24 h at 37°C with multiplicities of infection of 0.0001, 0.001, 0.01, 0.1, 1, 10, and 100. In food matrices (milk and chicken meat), treatment with phage vB_SalP_TR2 also reduced the number of S. Albany compared with that in controls. These findings highlighted phage vB_SalP_TR2 as a potential antibacterial agent for the control of Salmonella in food samples.

RESUMEN

BACKGROUND: Staphylococcus aureus (S. aureus) is a major contributor to nosocomial and community-acquired infections. S. aureus small colony variants (SCVs) which changed in relevant phenotype have made more limited and difficult for therapeutic options against S. aureus infections increasingly. Rifampicin is considered as the "last-resort" antibiotic against S. aureus. Our study investigated resistance profiles and biological characteristics of rifampicin-resistant S. aureus SCVs. METHODS: We collected S. aureus SCVs that were selected from 41 rifampicin-resistant clinical isolates. Then, biological characteristics, resistance spectrum, and rifampicin resistance mechanisms of tested S. aureus SCVs and corresponding parental strains were investigated by classic microbiological methods, agar dilution method, polymerase chain reaction (PCR). Moreover, the fitness cost of S. aureus SCVs, including growth, biofilm formation ability, and virulence profile, was also determined by bacterial growth curve assay, biofilm formation assay, and Galleria mellonella infection model. RESULTS: There were three S. aureus SCVs (JP310 SCVs, JP1450 SCVs, JP1486 SCVs) that were selected from 41 rifampicin-resistant S. aureus. S. aureus SCVs colonies were tiny, with decreased pigmentation, and the hemolysis circle was not obvious compared with corresponding parental strains. And SCVs could not be restored to normal-colony phenotype after hemin, menaquinone, or thymidine supplementation. Different rpoB mutations occurred in JP1486 SCVs. Antimicrobial susceptibility testing revealed MICs of SCVs were higher than corresponding parental strains. Besides, the growth ability and virulence of SCVs were lower, and biofilm formation ability of which increased compared with parental strains. CONCLUSION: S. aureus SCVs share the rifampicin resistance mechanisms with parental strains, although there were some differences in the position of rpoB mutations. Moreover, we found that the biological characteristics of SCVs were significantly different from corresponding parental strains. In contrast, decreased susceptibility to other antibiotics of SCVs was observed during phenotype switch. Furthermore, SCVs incur the fitness cost.

RESUMEN

West Nile virus (WNV) is an important neurotropic flavivirus that is widely distributed globally. WNV strain XJ11129 was first isolated in Xinjiang, China, and its genetic and biological characteristics remain largely unknown. In this study, phylogenetic and sequence analyses revealed that XJ11129 belongs to lineage 1a and shares high genetic identity with the highly pathogenic strain NY99. Then, the full-length genomic cDNA of XJ11129 was amplified and assembled using a modified Gibson assembly (GA) method. The virus (named rXJ11129) was successfully rescued in days following this method. Compared with other wild-type WNV isolates, rXJ11129 exhibited virulence indistinguishable from that of the NY99 strain in vivo. In summary, the genomic and virulence phenotypes of rXJ11129 were characterized in vivo and in vitro, and these data will improve the understanding of the spread and pathogenesis of this reemerging virus.

Asunto(s)

RESUMEN

Intervertebral disc (IVD) degenerative diseases are a common problem in the world, and they cause substantial social and economic burdens for people. The current methods for treating IVD degenerative diseases mainly include surgery and conservative treatment, which cannot fundamentally restore the normal structure of the disc. With continuous research on the mechanism of degeneration and the development of regenerative medicine, rapid progress has been made in the field of regenerative medicine regarding the use of stem cell-derived exosomes, which are active biological substances used in intercellular communication, because they show a strong effect in promoting tissue regeneration. The study of exosomes in the field of IVD degeneration has just begun, and many surprising achievements have been made. This paper mainly reviews the biological characteristics of exosomes and highlights the current status of exosomes in the field of IVD degeneration, as well as future developments regarding exosomes.

RESUMEN

3-Ketosteroid Δ1-dehydrogenase (KsdD) is the key enzyme responsible for Δ1-dehydrogenation, which is one of the most valuable reactions for steroid catabolism. Arthrobacter simplex has been widely used in the industry due to its superior bioconversion efficiency, but KsdD information is not yet fully clear. Here, five KsdD homologues were identified in A. simplex CGMCC 14539. Bioinformatic analysis indicated their distinct properties and structures. Each KsdD was functionally confirmed by transcriptional response, overexpression, and heterologous expression. The substantial difference in substrate profiles might be related to the enzyme loop structure. Two promising enzymes (KsdD3 and KsdD5) were purified and characterized, exhibiting strong organic solvent tolerance and clear preference for 4-ene-3-oxosteroids. KsdD5 seemed to be more versatile due to good activity on substrates with or without a substituent at C11 and high optimal temperature and also possessed unique residues. It is the first time that KsdDs have been comprehensively disclosed in the A. simplex industrial strain.

Asunto(s)

RESUMEN

High relapse rate of acute myeloid leukemia (AML) is still a crucial problem despite considerable advances in anti-cancer therapies. One crucial cause of relapse is the existence of leukemia stem cells (LSCs) with self-renewal ability, which contribute to repeated treatment resistance and recurrence. Treatments targeting LSCs, especially in combination with existing chemotherapy regimens or hematopoietic stem cell transplantation might help achieve a higher complete remission rate and improve overall survival. Many novel agents of different therapeutic strategies that aim to modulate LSCs self-renewal, proliferation, apoptosis, and differentiation are under investigation. In this review, we summarize the latest advances of different therapies in development based on the biological characteristics of LSCs, with particular attention on natural products, synthetic compounds, antibody therapies, and adoptive cell therapies that promote the LSC eradication. We also explore the causes of AML recurrence and proposed potential strategies with new dimensions for targeting LSCs in the future.

Asunto(s)

RESUMEN

The oriental armyworm, Mythimna separata is an important crop pest in eastern Asia. Nocturnal insects, including nocturnal moths, have phototactic behavior to an artificial light source. Phototactic behavior in insects is species-specific in response to different wavelengths of light sources. Our previous study showed that green (520 nm) light emitting diode (LED) light resulted in a significantly higher phototactic behavior in M. separata moths compared to the other wavelength LED lights. The goal of the present study is to investigate the influence of green light illumination on biological characteristics of different developmental stages in M. separata. Our results revealed that when different developmental stages of M. separata were exposed to the green light illumination in a dark period, several biological characteristics in all developmental stages except for egg stage were positively changed, but those of F1 generation M. separata which are next generation of the adults exposed to the green light did not significantly change compared with the control level. These findings suggest that green light illumination at night (or dark period) has a positive effect on the development and longevity of M. separata.

Asunto(s)

RESUMEN

Cyclospora cayetanensis, a coccidian parasite that causes protracted and relapsing gastroenteritis, has a short recorded history. At least 54 countries have documented C. cayetanensis infections and 13 of them have recorded cyclosporiasis outbreaks. Cyclospora cayetanensis infections are commonly reported in developing countries with low-socioeconomic levels or in endemic areas, although large outbreaks have also been documented in developed countries. The overall C. cayetanensis prevalence in humans worldwide is 3.55%. Among susceptible populations, the highest prevalence has been documented in immunocompetent individuals with diarrhea. Infections are markedly seasonal, occurring in the rainy season or summer. Cyclospora cayetanensis or Cyclospora-like organisms have also been detected in food, water, soil and some other animals. Detection methods based on oocyst morphology, staining and molecular testing have been developed. Treatment with trimethoprim-sulfamethoxazole (TMP-SMX) effectively cures C. cayetanensis infection, whereas ciprofloxacin is less effective than TMP-SMX, but is suitable for patients who cannot tolerate co-trimoxazole. Here, we review the biological characteristics, clinical features, epidemiology, detection methods and treatment of C. cayetanensis in humans, and assess some risk factors for infection with this pathogen.

Asunto(s)

RESUMEN

Objective: To explore the effects of varies osmotic pressure induced by adding fluoride into the medium on the biological characteristic of ameloblast.Methods: Ameloblasts were cultured in vitro on the fifth day were seeded and purified. DMEM medium containing different concentrations of NaF (0, 42, 84 mg/L), NaCl (58.5 and 117 mg/L), glycerol (0.05 and 0.09 mg/L) and sorbitol (1 and 1.5 mg/L) was added into the cells, which were then cultured for 48 hours. The survival and proliferation of ameloblasts in different groups were detected by MTT. The apoptosis rate was measured by flow cytometry and the expressions of CK14 and KLK4 by Real-time PCR. Results: MTT showed that with the increase of osmolality, cell proliferation decreased; however, the most obvious one was in NaF group. Streaming apoptosis detection showed that with the increase of osmolality, the apoptosis rate of cells increased, which was most obvious in NaF group. Real-time PCR showed that the mRNA expressions of CK14 and KLK4 decreased with the increase of osmolality, and that they were lower in NaF 42 mg/L group than in the other control groups. Results: The change in osmotic pressure of the medium affects the proliferation, apoptosis and mRNA expression of ameloblasts. The biological change of ameloblasts cultured in medium containing different concentration of NaF is mainly due to the toxic effects of fluoride ions.

RESUMEN

OBJECTIVE: To compare the difference of fertility of Biomphalaria glabrata snails between self-fertilization and cross-fertilization and to observe the circadian rhythm of laying eggs, the effect of light on laying eggs and the tolerance of the snail to water and food deficiency, so as to provide the evidence for control and elimination of B. glabrata snails in the field. METHODS: Under laboratory conditions, a single B. glabrata egg for self-fertilization was separated and hatched individually, and young snails were raised in different plastic boxes individually. The eggs for cross-fertilization were hatched and the young snails were fed in the same plastic box. The ability of spawn, the development of the eggs, and the number of snails growing from young to adult snails were compared between the self-fertilization and cross-fertilization. The snails were in the water under four environments, all day illumination, all day without illumination, daytime lighting and night without illumination, and daytime without illumination but night lighting. The eggs were collected and counted daily. The circadian rhythm of spawn and the effect of illumination on spawn were observed. The adult snails were divided into 6 groups and exposed to the environments with relative humidity of 0, 65%, 87% and 100%, respectively. The survival rates of the adult snails exposed to the different environments after different time were observed. The adult snails were placed at 25 °C in the oven to remove water content from the soft body of snails. When the dehydration rates of the soft bodies achieved 10%, 20%, 30%, 40%, 50%, 52%, 55%, 57%, 60%, and 70% respectively, the survival rates of the adult snails exposed to the oven were observed. RESULTS: In the 25 °C water, the average laying egg number for 15 days per snail was (8.77 ± 16.92) eggs/snail in the self-fertilization snail. The average laying egg number for 15 days per snail was (149.71 ± 142.28) eggs/snail in the cross-fertilization snails. There was a significant difference between the self-fertilization snail and cross-fertilization snail (t = 0.999 999, P < 0.01). The hatching rate and reproductive maturation rate of the self-fertilization snails and cross-fertilization snails were 50.1% and 78.9%, and 19.3% and 3.8%, respectively, There was a significant difference (the hatching rate: χ2 = 18.18, P < 0.01, the reproductive maturation rate: χ2 = 11.83, P < 0.01) . In the natural environment of daytime with illumination and nighttime with darkness, the amount of laying 20 eggs of B. glabrata snail was (944.07 ± 392.53) eggs/day during a whole day, among them the amount of laying eggs during daytime account for 10.1% and the amount of laying eggs during nighttime account for 89.9%, and the laying egg was given priority to with the night. The above results suggested that the dark environment was conducive to B. glabrata snails to lay eggs. The above results suggested that light can promote the increase of spawning of B. glabrata. When B. glabrata was exposed to the environments with the relative humidity of 0, 65%, 87% and 100% at 25 °C, respectively, and the longest survival times of snails were 7, 70, 150 d and 100 d, respectively. In the 25 °C water, the snails could survive for 50 days without food. The adult snails were placed at 25 °C in the oven to remove water content from the soft body of snails. When the dehydration rates of the soft bodies achieved 10%, 20%, 30%, 40%, 50%, 52%, 55%, 57%, 60%, and 70% respectively, the survival rates of the adult snails exposed to the oven were 100%, 100%, 100%, 100%, 70%, 30%, 0, 0, 0 and 0, respectively. CONCLUSIONS: B. glabrata can achieve the reproductive process by cross-fertilization or self-fertilization. There is a significant difference in reproductive ability between the cross-fertilization snail and self-fertilization snail, cross-fertilization is stronger than self-fertilization, but the rate of reproduction in the self-fertilization is higher than that in the cross-fertilization. It is indicated that B. glabrata that survive after the dry season plays an important role in the maintenance of local snail populations and transmission of schistosomiasis mansoni.

Asunto(s)

RESUMEN

Clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated (Cas)9 is a novel and convenient gene editing system that can be used to construct genetically modified animals. Recombination activating gene 2 (Rag2) is a core component that is involved in the initiation of V(D)J recombination during T- and B-cells maturation. Separately, the interleukin-2 receptor gamma chain gene (IL2rg) encoded the protein-regulated activity of natural killer (NK) cells and shared common receptors of some cytokines. Rag2 and IL2rg mutations cause immune system disorders associated with T-, B-, and NK cell function and some cytokine activities. In the present study, 2 single-guide RNAs (sgRNAs) targeted on Rag2 and IL2rg genes were microinjected into the zygotes of BALB/c mice with Cas9 messenger RNA (mRNA) to create Rag2/IL2rg -/- double knockout mice, and the biological characteristics of the mutated mice were subsequently analyzed. The results showed that CRISPR/Cas9-induced indel mutation displaced the frameshift of Rag2 and IL2rg genes, resulting in a decrease in the number of T-, B-, and NK cells and the destruction of immune-related tissues like the thymus and spleen. Mycobacterium tuberculosis 85B antigen could not induce cellular and humoral immune response in mice. However, this aberrant immune activity compromised the growth of several tumor heterogenous grafts in the mutated mice, including orthotopic and subcutaneous transplantation tumors. Thus, Rag2/IL2rg -/- knockout mice possessed features of severe combined immunodeficiency (SCID), which is an ideal model for human xenograft.

RESUMEN

Schistosomiasis is one of zoonoses (diseases that are naturally transmitted between vertebrate animals and human),and it is widespread in tropical and sub-tropical regions. It is one of the important infectious diseases that the World Health Organization plans to eliminate. Hybridization within Genus Schistosoma is an emerging public health concern in our changing world.Schistosoma spp. are dioecious trematode, in which there are lots of species infecting human and animals. Several schistosome species also overlap in their geographical and host range, which allows male and female schistosomes of different species to pair within their definitive hosts. The hybridization among different species and the production of dominant hybrid species and changes of their biological characteristics, such as host selectivity, fertility and infectivity, can lead to the evolution of schistosoma species, regional distribution of the population, the changes of epidemic patterns, and pathogenicity to human and animals, and all of them have an impact on the global schistosomiasis elimination plan.

Asunto(s)

RESUMEN

Objective • To screen for a bacteriophage of a drug-resistant Klebsiella pneumoniae strain and assess its eligibility to be incorporated into the Klebsiella bacteriophage library. Methods • A drug-resistant Klebsiella pneumoniae strain isolated from a patient with urinary infection was used as the host strain. Phage screening was carried out in environmental sewage, and the bacteriophage was isolated, purified, characterized and sequenced. Safety evaluation was also conducted based on the genome sequence. Results • A drug-resistant Klebsiella pneumoniae bacteriophage was isolated and designated as JD902, which belonged to Caudovirales. The burst size was 88 pfu/cell, and it could maintain good activity in pH range 4.0-11.0. Genomic analysis demonstrated that it did not carry any antibiotic resistance genes and virulence factor genes. Conclusion • JD902 is a virulent phage with high stability and safety in vitro. It can be incorporated into bacteriophage library for clinical treatment.

RESUMEN

Objective: To explore the effects of the microenvironment of rabbit bladder acellular matrix graft (BAMG) on proliferation, cell surface markers, and molecular protein level of human bone marrow mesenchymal stem cells (hBMSCs). Methods: We prepared BAMG immersion fluid medium and detected its effect on the proliferation of hBMSCs by MTT method. The expressions of CD44, CD45, CD73 and PDGFRβ were detected by flow cytometry. The expressions of PPAR, OCN and α-SMA were detected by RT-PCR, and the expression of OCT was detected by Western blot. Results: hBMSCs had good compatibility with BAMG. The MTT method showed that BAMG and BAMG immersion medium did not affect the proliferation capacity of hBMSCs. The surface of hBMSCs cells cultured with immersion fluid still expressed CD44, CD73 and PDGFRβ, but not CD45. RT-PCR showed that OCN, PPAR, and α-SMA were all expressed. Western blot test also showed the positive expression of OCT-4. Conclusion: hBMSCs can still keep their original biological characteristics in the microenvironment of rabbit BAMG. It can be the seed cells and combined substrate materials for urinary system tissue engineering.

RESUMEN

Mesenchymal stem cells (MSCs) are a kind of stem cells with multidirectional differentiation potential.In most studies,MSCs were cultured under atmospheric oxygen tension,and the concentration of oxygen was 21％,which could not reflect their normal physiological state.In this paper,we will review the recent advance in effect of hypoxic preconditioning on phenotype,proliferation,differentiation,migration and other biological characteristics of MSCs.

RESUMEN

Schistosomiasis is one of zoonoses (diseases that are naturally transmitted between vertebrate animals and human),and it is widespread in tropical and sub-tropical regions. It is one of the important infectious diseases that the World Health Organization plans to eliminate. Hybridization within Genus Schistosoma is an emerging public health concern in our changing world.Schistosoma spp. are dioecious trematode, in which there are lots of species infecting human and animals. Several schistosome species also overlap in their geographical and host range, which allows male and female schistosomes of different species to pair within their definitive hosts. The hybridization among different species and the production of dominant hybrid species and changes of their biological characteristics, such as host selectivity, fertility and infectivity, can lead to the evolution of schistosoma species, regional distribution of the population, the changes of epidemic patterns, and pathogenicity to human and animals, and all of them have an impact on the global schistosomiasis elimination plan.