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BACKGROUND: The erector spinae plane block (ESPB) is an interfascial plane block for managing neuropathic thoracic pain. Although the ESPB is applied widely in various clinical situations, no studies have evaluated the association between the analgesic outcomes of the ESPB and the numerical changes in the perfusion index (PI) and PI ratio. OBJECTIVES: The purpose of this study is to investigate the association between the clinical response following ESPB and other possible factors, including changes in the PI and PI ratio. STUDY DESIGN: A prospective, nonrandomized, and open-label study. SETTING: The pain clinic of a tertiary university hospital. METHODS: This study included 92 patients with neck or arm pain who received T2 ESPB using 20 mL of 0.2% ropivacaine. To aid in the prediction of clinical outcomes, the PI was measured at the blocked side for 30 minutes as soon as the ESPB was finished. Various demographic data were also analyzed to predict the clinical outcomes. RESULTS: Among 92 patients, 59 patients (64%) showed successful treatment outcomes (> 50% reduction in the numerical rating scale score or > 30% reduction in the neck disability index). The baseline PI of the responders was statistically higher than the nonresponders' (P < 0.05). Also, the responders' PI demonstrated statistically higher values than the nonresponders' at the time points of 4, 6, and 8 minutes after the ESPB. Multivariate logistic regression analysis revealed that a higher baseline PI (OR, 1.91; 95% CI, 1.27-2.86; P = 0.002) was an independent factor associated with a successful outcome. LIMITATIONS: Only a small number of patients with nonspinal diseases were included, except for those who had cervical radiculopathy. Therefore, it is hard to conclude that thoracic ESPB has any therapeutic benefits to patients with nonspinal diseases such as complex regional pain syndrome, adhesive capsulitis, or post-thoracotomy pain syndrome. CONCLUSION: A successful outcome at 4 weeks after T2 ESPB was achieved in 64% of patients with cervical radiculopathy. A higher baseline PI value was an independent factor associated with a successful response to T2 ESPB.
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Bloqueo Nervioso , Radiculopatía , Humanos , Bloqueo Nervioso/métodos , Masculino , Femenino , Persona de Mediana Edad , Radiculopatía/tratamiento farmacológico , Radiculopatía/terapia , Estudios Prospectivos , Resultado del Tratamiento , Adulto , Anestésicos Locales/administración & dosificación , Anciano , Ropivacaína/administración & dosificación , Dimensión del DolorRESUMEN
Green pesticides, derived from natural sources, have gained wider attention as an alternative to synthetic pesticides for managing polyphagous pests, such as Spodoptera litura. In this study, the methanolic flower extract of Nyctanthes arbor-tristis (Mx-Na-t) was subjected to chemical screening, and 3-hydroxy-1,2-dimethyl-4(1H)-pyridone (3H-dp) and tyrosol (Ty-ol) were identified as the major derivatives. The toxic effects of Mx-Na-t (500 ppm) were highest in third-instar S. litura larvae (96.4%), while those of 3H-dp and Ty-ol (5 ppm) were highest in second-instar larvae (76.5% and 81.4%, respectively). The growth and development of S. litura larvae and pupae were significantly reduced by all three treatments. Fecundity rates were also reduced by all treatments [from 1020 eggs (control) to 540 eggs by Mx-Na-t treatment, 741 eggs by 3H-dp treatment, and 721 eggs by Ty-ol treatment]. The extract and its active constituents decreased adult emergence and slowed total larval development in a dose-dependent manner. A decrease was noted in the major gut enzymes of young S. litura larvae exposed to Mx-Na-t, 3H-dp, and Ty-ol. Moreover, midgut tissues of fourth-instar larvae were severely damaged by Mx-Na-t (250 ppm), 3H-dp (2.5 ppm), and Ty-ol (2.5 ppm); the treatments induced structural damage to the epithelial cells and gut lumen. The earthworm Eisenia fetida was used to assess nontarget toxicity. Compared with cypermethrin, the phytochemicals exhibited minimal effects on the earthworm's detoxifying enzymes superoxide dismutase and catalase after 14 days of treatment. Moreover, in silico predictions using BeeTox and ProTox-II indicated little or no toxicity of 3H-dp and Ty-ol toward honey bees and other nontarget species.
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Flores , Larva , Oligoquetos , Extractos Vegetales , Spodoptera , Animales , Spodoptera/efectos de los fármacos , Oligoquetos/efectos de los fármacos , Extractos Vegetales/toxicidad , Larva/efectos de los fármacos , Flores/química , Inhibidores Enzimáticos/toxicidadRESUMEN
Current vector control strategies based on synthetic chemicals are not eco-friendly against non-target organisms; hence, alternative approaches are highly required. Commercially purchased oil of Mentha spicata (Spearmint) and Eucalyptus citriodora (Citriodora) were examined against the medical pest Cx. quinquefasciatus (Say) and their non-toxicity on the aquatic species was evaluated. Chemical screening with gas chromatography coupled with mass spectrometry (GC-MS) analysis revealed a total of 14 and 11 compounds in Citriodora and Spearmint oils, respectively, with the highest peak (%) at carvone (70.44%) and isopulegol (30.4%). The larvicidal activity on the fourth instar larvae of Cx. quinquefasciatus showed dose-dependent mortality and significance at a 100 ppm concentration 48 h post-treatment with Citriodora (76.4%, P ≤ 0.001) and Spearmint (100%, P ≤ 0.001). Additionally, the photomicrograph of the fourth instar larvae revealed significant physical abnormalities in the head and midgut tissues post-exposure to Spearmint and Citriodora oils. Moreover, the histological assay revealed severe damage in the epithelial cells and gut lumen 2 to 24 h post-treatment. The repellency percentage of adult Culex mosquitoes was prominent across both oils at 150 ppm 210 min post-exposure. Non-target toxicity on the aquatic predator showed both essential oils (Spearmint oil (17.2%) and Citriodora oil (15.2%)) are safer at the maximum treatment (200 ppm) compared to temephos (75.4% at 1 ppm). The in silico screening of phyto-compounds derived by both essential oils with BeeTox (online server) showed no contact toxicity to the honey bee Apis mellifera. Overall, the present research revealed that Spearmint and Citriodora essential oils and their active phyto-compounds were toxic to Cx. quinquefasciatus and harmless to the aquatic predator and honey bee.
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Culex , Eucalyptus , Insecticidas , Mentha spicata , Aceites Volátiles , Abejas , Animales , Mentha spicata/química , Insecticidas/química , Mosquitos Vectores , Aceites Volátiles/farmacología , Aceites Volátiles/química , Aceite de Eucalipto , LarvaRESUMEN
BACKGROUND: The erector spinae plane block (ESPB), which was introduced to manage the thoracic pain, is a technical easy and less invasive ultrasound-guided technique. Although the ESPB is used widely in various clinical situations, no studies have evaluated the association between the clinical outcomes of the ESPB and the numerical changes of the perfusion index (PI). OBJECTIVES: The purpose of this study is to investigate the association between the clinical response following ESPB and other possible factors including the changes of PI. STUDY DESIGN: Prospective, nonrandomized, and an open-label study. SETTING: The pain clinic of a tertiary university hospital. METHODS: This study included 91 patients of low back pain with degenerative spinal disease who received L4 ESPB using 20 mL of 0.2% ropivacaine. For the predication of clinical outcome, the PI was measured for 30 min at the blocked side subsequent to the ESPB. Various demographic data were also analyzed to predict the clinical outcomes. RESULTS: The PI of the responder group was higher value than that of the nonresponder group until 30 min but did not show any statistically significant differences. Multivariate logistic regression analysis revealed that the duration of pain (odds ratio [OR], 0.95; 95% CI, 0.90-1.00; P = 0.043), the right side injection (OR, 3.87; 95% CI, 1.42-10.55; P = 0.008), and the PI ratio of 1.5-3 at 10 min (OR, 3.79; 95% CI, 1.36-10.57; P = 0.011), were independent factors associated with successful outcomes. LIMITATION: The responder and the nonresponders were categorized using only changes of the numeric rating scale. The categorization based on the changes of functional disability or quality of life was not used. CONCLUSION: The right side injection, duration of pain less than 3 months, PI ratio of 1.5-3 at 10 min following the ESPB were associated with successful clinical outcomes.
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Dolor de la Región Lumbar , Bloqueo Nervioso , Radiculopatía , Humanos , Radiculopatía/tratamiento farmacológico , Estudios Prospectivos , Dolor en el PechoRESUMEN
Toll and IMD pathways regulate antimicrobial innate immune responses in insect model systems. The transcriptional activation of antimicrobial peptides (AMPs) confers humoral immunity in the host against invaded pathogens. The IKK kinase complex (IKKα, IKKß, and the regulatory subunit IKKγ/NEMO) centrally regulates the NF-κB response to various stimuli. It triggers an appropriate antimicrobial immune response in the host. In this study, a TmIKKß (or TmIrd5) homolog was screened from the RNA-seq database of the coleopteran beetle, Tenebrio molitor. A single exon characterizes the TmIKKß gene, and the open reading frame (ORF) comprises of 2112 bp that putatively encodes a polypeptide of 703 amino acid residues. TmIKKß contains a serine/threonine kinase domain and is phylogenetically close to Tribolium castaneum IKKß homolog (TcIKKß). TmIKKß transcripts were highly expressed in the early pupal (P1) and adult (A5) stages. Among the tissues, TmIKKß showed higher expression in the integument of the last instar larvae and the fat body and hemocytes of 5-day-old adults. TmIKKß mRNA was upregulated post-E. coli challenge to the host. Moreover, RNAi-based TmIKKß mRNA silencing increased host larvae' susceptibility against E. coli, S. aureus and C. albicans. TmIKKß RNAi in the fat body led to a downregulation in mRNA expression of ten out of fourteen AMP genes, including TmTenecin1, -2, and -4; TmDefensin, and -like; TmColeoptericinA, and -B; and TmAttacin1a, -1b, and -2, suggesting the requirement of the gene in antimicrobial innate immune responses. Further, a decrease in the mRNA expression of NF-κB factors such as TmRelish, TmDorsal1, and TmDorsal2 in the fat body of T. molitor larvae was observed post-microorganisms challenge. Thus, TmIKKß regulates antimicrobial innate immune responses in T. molitor.
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Antiinfecciosos , Tenebrio , Animales , Quinasa I-kappa B/genética , Quinasa I-kappa B/metabolismo , FN-kappa B/metabolismo , Escherichia coli , Secuencia de Aminoácidos , Staphylococcus aureus , Inmunidad Innata , Antiinfecciosos/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , ARN Mensajero/metabolismoRESUMEN
BACKGROUND: The development of back pain following epidural analgesia is one reason for patient refusal of neuraxial analgesia. The primary endpoint of this study was to compare the incidence and severity of back pain following midline and paramedian epidural technique. The secondary endpoint was to identify the risk factors associated with the occurrence of back pain. METHODS: This prospective randomized study included 114 patients receiving thoracic epidural catheterization for pain management following upper abdominal or thoracic surgery. Patients were allocated to either the midline or the paramedian group by computer-generated randomization. An investigator who was blinded to the patient group interviewed patients at 24, and 48 h, and 3-5 days after surgery about the existence of back pain and its severity. RESULTS: The total incidence of back pain following epidural anesthesia was 23.8% in the midline group and 7.8% in the paramedian group. The numerical rating scale of back pain was not different between the two groups at 24 h and 4 days after surgery. The paramdian technique was associated with a lower incidence of back pain than the midline technique (95% confidence interval 0.05-0.74, odds ratio 0.2, P < 0.01). However, the number of attempts, surgical position, body mass index, and duration of surgery were not associated with back pain. CONCLUSIONS: This study showed that the midline group of thoracic epidural analgesia demonstrated higher incidence of back pain than the paramedian group. However, the pain was mild in intensity and decreased with time in both groups.
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BACKGROUND: Inadvertent intravascular injection of local anesthetics can lead to false negative results following a lumbar medial branch block (MBB) performed to diagnose facet joint origin pain. A previous study demonstrated that the type of needle could affect the incidence of intravascular injection rates. OBJECTIVES: The primary endpoint of this study was to compare the incidence of intravascular injection during lumbar MBB between the Quincke and Touhy needles. The secondary endpoint of this study was to compare the injection time, radiation dose, and patient discomfort during lumbar MBB between the needle types. STUDY DESIGN: Prospective randomized trial. SETTING: An interventional pain management practice in South Korea. METHODS: The incidence of intravascular uptake of contrast medium was compared using the Touhy and Quincke needles under real-time fluoroscopy during lumbar MBB. Injection time, radiation dose, and patient discomfort during lumbar MBB were also compared. RESULTS: The incidence of intravascular injection was 21.8% (21/102) in the Touhy needle group and 21.2% (22/99) in the Quincke needle group. The odds ratio for the association between the needle types and intravascular injection was 1.1. The injection time, radiation dose, and patient discomfort during lumbar MBB were similar between the Touhy and Quincke needle groups. LIMITATIONS: This study was performed from L2 to L4 MBB of the unilateral lumbar region. Although the type of needle assigned to the patient was randomized, 3 needles, which are used for 3 levels of MBB, were identical. CONCLUSIONS: The overall incidence rate of intravascular injection during lumbar MBB was nearly 20% under real-time fluoroscopy for both types of needle. Use of the Touhy needle did not reduce the intravascular injection rate nor the injection time, radiation dose, and patient discomfort.
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Región Lumbosacra , Agujas , Bloqueo Nervioso , Anestésicos Locales , Humanos , Manejo del Dolor/métodos , Estudios ProspectivosRESUMEN
BACKGROUND: Normal saline or contrast medium is one of the widely used injection materials during fluoroscopic guided injections. Optic nerve sheath diameter (ONSD) measurement is a reliable and noninvasive method for intracranial pressure evaluation. OBJECTIVES: The purpose of this study was to compare the increase in ONSD and cerebral oxygen saturation (rSO2) between normal saline and contrast medium when they were injected into the epidural space. STUDY DESIGN: Prospective randomized trial. SETTING: An interventional pain management clinic in South Korea. METHODS: This study included 42 patients who were scheduled to receive thoracic epidural catheterization for postoperative pain control. Patients were randomly allocated to receive 5 mL normal saline or contrast medium following successful thoracic epidural entry. The ONSD was measured using transorbital sonography at baseline (T0), 10 min (T10), 20 min (T20), and 40 min (T40) after epidural normal saline or contrast medium injection. RESULTS: Both groups demonstrated significant increases in ONSD from T10 to T40 when compared with the baseline. Although both groups showed a significant increase in ONSD compared with the baseline, group saline showed a higher increase in ONSD than group contrast. A significantly higher increase in ONSD in group saline than in group contrast was maintained from T10 to T40 (P = 0.015). LIMITATIONS: We could not determine the returning point of the normalized ONSD value. CONCLUSION: Thoracic epidural injection of 5 mL normal saline or contrast medium resulted in a significant increase of ONSD compared to baseline; however, the degree of ONSD increase was more attenuated in the contrast group than the saline group.
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Espacio Epidural , Hipertensión Intracraneal , Espacio Epidural/diagnóstico por imagen , Humanos , Nervio Óptico/diagnóstico por imagen , Estudios Prospectivos , Solución Salina , Ultrasonografía/métodosRESUMEN
Vertebrates rely on the most sophisticated adaptive immunity to defend themselves against various pathogens. This includes immunologic memory cells, which mount a stronger and more effective immune response against an antigen after its first encounter. Unlike vertebrates, invertebrates' defense completely depends on the innate immunity mechanisms including humoral and cell-mediated immunity. Furthermore, the invertebrate equivalent of the memory cells was discovered only recently. Since the discovery of transgenerational immune priming (TGIP) in crustaceans, numerous findings have proven the IP in invertebrate classes such as insects. TGIP can be induced through maternal priming pathways such as transcriptional regulation of antimicrobial peptides, and also paternal IP including the induction of proPO system activity. We appraise the diversity and specificity of IP agents to provide sustained immunologic memory in insects, particularly T. molitor in the review. An understanding of IP (more so TGIP) response in T. molitor will deepen our knowledge of invertebrate immunity, and boost the mass-rearing industry by reducing pathogen infection rates.
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Tenebrio , Animales , Inmunidad Innata , Memoria Inmunológica , InsectosRESUMEN
Innate immunity is the ultimate line of defense against invading pathogens in insects. Unlike in the mammalian model, in the insect model, invading pathogens are recognized by extracellular receptors, which activate the Toll signaling pathway through an extracellular serine protease cascade. In the Toll-NF-κB pathway, the extracellular spätzle protein acts as a downstream ligand for Toll receptors in insects. In this study, we identified a novel Spätzle isoform (TmSpz1b) from RNA sequencing database of Tenebrio molitor. TmSpz1b was bioinformatically analyzed, and functionally characterized for the antimicrobial function by RNA interference (RNAi). The 702 bp open reading frame of TmSpz1b encoded a putative protein of 233 amino acid residues. A conserved cystine-knot domain with seven cysteine residues in TmSpz1b was involved in three disulfide bridges and the formation of a spätzle dimer. TmSpz1b was mostly expressed in the hemocytes of T. molitor late instar larvae. The mRNA expression of TmSpz1b was highly induced in the hemocytes after Escherichia coli, Staphylococcus aureus, and Candida albicans stimulation of T. molitor larvae. TmSpz1b silenced larvae were significantly more susceptible to E. coli infection. In addition, RNAi-based functional assay characterized TmSpz1b to be involved in the positive regulation of antimicrobial peptide genes in hemocytes and fat bodies. Further, the TmDorX2 transcripts were downregulated in TmSpz1b silenced individuals upon E. coli challenge suggesting the relationship to Toll signaling pathway. These results indicate that TmSpz1b is involved in the T. molitor innate immunity, causes the sequestration of Gram-negative bacteria by the regulatory action of antimicrobial peptides, and enhances the survival of T. molitor larvae.
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Microstructures and corrosion properties of pure titanium were characterized when iron was used as a grain refiner. The added Fe element acted as a strong grain refiner for pure titanium by forming ß Ti phase at grain boundaries, and 0.15 wt% Fe was revealed to be a sufficient amount to make the grain size of pure titanium below 20 µm, which was the requirement for the desired titanium cathode. However, corrosion resistance was decreased with the Fe amount added. From the open circuit potential (OCP) results, it was obvious that the TiO2 stability against the reducing acid environment was deteriorated with the Fe amount, which seemed to be the main reason for the decreased corrosion resistance. Electrochemical impedance spectroscopy (EIS) results showed that both the decrease in the compact oxide film's resistance (Rb) and the appearance of the outer porous film occurred as a result of the dissolution of the TiO2 layer, whose phenomena became more apparent as more Fe was added.
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The cystine knot protein Spätzle is a Toll receptor ligand that modulates the intracellular signaling cascade involved in the nuclear factor kappa B (NF-κB)-mediated regulation of antimicrobial peptide (AMP)-encoding genes. Spätzle-mediated activation of the Toll pathway is critical for the innate immune responses of insects against Gram-positive bacteria and fungi. In this study, the open reading frame (ORF) sequence of Spätzle-like from T. molitor (TmSpz-like) identified from the RNA sequencing dataset was cloned and sequenced. The 885-bp TmSpz-like ORF encoded a polypeptide of 294 amino acid residues. TmSpz-like comprised a cystine knot domain with six conserved cysteine residues that formed three disulfide bonds. Additionally, TmSpz-like exhibited the highest amino acid sequence similarity with T. castaneum Spätzle (TcSpz). In the phylogenetic tree, TmSpz-like and TcSpz were located within a single cluster. The expression of TmSpz-like was upregulated in the Malpighian tubules and gut tissues of T. molitor. Additionally, the expression of TmSpz-like in the whole body and gut of the larvae was upregulated at 24 h post-E. coli infection. The results of RNA interference experiments revealed that TmSpz-like is critical for the viability of E. coli-infected T. molitor larvae. Eleven AMP-encoding genes were downregulated in the E. coli-infected TmSpz-like knockdown larvae, which suggested that TmSpz-like positively regulated these genes. Additionally, the NF-κB-encoding genes (TmDorX1, TmDorX2, and TmRelish) were downregulated in the E. coli-infected TmSpz-like knockdown larvae. Thus, TmSpz-like plays a critical role in the regulation of AMP production in T. molitor in response to E. coli infection.
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Péptidos Catiónicos Antimicrobianos/metabolismo , Infecciones por Escherichia coli/microbiología , Escherichia coli/inmunología , Inmunidad Innata/inmunología , Proteínas de Insectos/metabolismo , Staphylococcus aureus/inmunología , Tenebrio/inmunología , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Infecciones por Escherichia coli/inmunología , Infecciones por Escherichia coli/metabolismo , Regulación del Desarrollo de la Expresión Génica , Proteínas de Insectos/genética , Larva/genética , Larva/inmunología , Larva/metabolismo , Larva/microbiología , Filogenia , Homología de Secuencia de Aminoácido , Infecciones Estafilocócicas , Tenebrio/genética , Tenebrio/metabolismo , Tenebrio/microbiologíaRESUMEN
The inhibitor of nuclear factor-kappa B (NF-κB) kinase (IKK) is the core regulator of the NF-κB pathway against pathogenic invasion in vertebrates or invertebrates. IKKß, -ε and -γ have pivotal roles in the Toll and immune deficiency (IMD) pathways. In this study, a homolog of IKKε (TmIKKε) was identified from Tenebrio molitor RNA sequence database and functionally characterized for its role in regulating immune signaling pathways in insects. The TmIKKε gene is characterized by two exons and one intron comprising an open reading frame (ORF) of 2,196 bp that putatively encodes a polypeptide of 731 amino acid residues. TmIKKε contains a serine/threonine protein kinases catalytic domain. Phylogenetic analysis established the close homology of TmIKKε to Tribolium castaneum IKKε (TcIKKε) and its proximity with other IKK-related kinases. The expression of TmIKKε mRNA was elevated in the gut, integument, and hemocytes of the last-instar larva and the fat body, Malpighian tubules, and testis of 5-day-old adults. TmIKKε expression was significantly induced by Escherichia coli, Staphylococcus aureus, and Candida albicans challenge in whole larvae and tissues, such as hemocytes, gut, and fat body. The knockdown of the TmIKKε messenger RNA (mRNA) expression significantly reduced the survival of the larvae against microbial challenges. Further, we investigated the induction patterns of 14 T. molitor antimicrobial peptides (AMPs) genes in TmIKKε gene-silencing model after microbial challenges. While in hemocytes, the transcriptional regulation of most AMPs was negatively regulated in the gut and fat body tissue of T. molitor, AMPs, such as TmTenecin 1, TmTenecin 4, TmDefensin, TmColeoptericin A, TmColeoptericin B, TmAttacin 1a, and TmAttacin 2, were positively regulated in TmIKKε-silenced individuals after microbial challenge. Collectively, the results implicate TmIKKε as an important factor in antimicrobial innate immune responses in T. molitor.
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IKKγ/NEMO is the regulatory subunit of the IκB kinase (IKK) complex, which regulates the NF-κB signaling pathway. Within the IKK complex, IKKγ/NEMO is the non-catalytic subunit, whereas IKKα and IKKß are the structurally related catalytic subunits. In this study, TmIKKγ was screened from the Tenebrio molitor RNA-Seq database and functionally characterized using RNAi screening for its role in regulating T. molitor antimicrobial peptide (AMP) genes after microbial challenges. The TmIKKγ transcript is 1521 bp that putatively encodes a polypeptide of 506 amino acid residues. TmIKKγ contains a NF-κB essential modulator (NEMO) and a leucine zipper domain of coiled coil region 2 (LZCC2). A phylogenetic analysis confirmed its homology to the red flour beetle, Tribolium castaneum IKKγ (TcIKKγ). The expression of TmIKKγ mRNA showed that it might function in diverse tissues of the insect, with a higher expression in the hemocytes and the fat body of the late-instar larvae. TmIKKγ mRNA expression was induced by Escherichia coli, Staphylococcus aureus, and Candida albicans challenges in the whole larvae and in tissues such as the hemocytes, gut and fat body. The knockdown of TmIKKγ mRNA significantly reduced the survival of the larvae after microbial challenges. Furthermore, we investigated the tissue-specific induction patterns of fourteen T. molitor AMP genes in TmIKKγ mRNA-silenced individuals after microbial challenges. In general, the mRNA expression of TmTenecin1, -2, and -4; TmDefensin1 and -2; TmColeoptericin1 and 2; and TmAttacin1a, 1b, and 2 were found to be downregulated in the hemocytes, gut, and fat body tissues in the TmIKKγ-silenced individuals after microbial challenges. Under similar conditions, TmRelish (NF-κB transcription factor) mRNA was also found to be downregulated. Thus, TmIKKγ is an important factor in the antimicrobial innate immune response of T. molitor.
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Antiinfecciosos/inmunología , Quinasa I-kappa B/inmunología , Inmunidad Innata/inmunología , Proteínas de Insectos/inmunología , Tenebrio/inmunología , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Candida albicans/inmunología , Regulación hacia Abajo/inmunología , Escherichia coli/inmunología , Expresión Génica/inmunología , Hemocitos/inmunología , Hemocitos/microbiología , Larva/inmunología , Larva/microbiología , ARN Mensajero/inmunología , Staphylococcus aureus/inmunología , Tenebrio/microbiologíaRESUMEN
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
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Autophagy is an important process by which pathogens and damaged or unused organelles are eliminated. The role of autophagy in development and the immune response to pathogens is well established. Autophagy-related protein 8 (Atg8) is involved in the formation of the autophagosome and, with the help of the serine protease Atg4, mediates the delivery of both vesicles and the autophagosome to the vacuole. Here, we cloned the Aedes albopictus autophagy-related protein 8 (AaAtg8) gene and characterized its role in the innate immunity of the mosquito against microbial infections. AaAtg8 is comprised of an open reading frame (ORF) region of 357 bp encoding a polypeptide of 118 amino acid residues. A domain analysis of AaAtg8 revealed an Atg8 ubiquitin-like domain, Atg7/Atg4 interaction sites, and peptide binding sites. The AaAtg8 mRNA expression was high in the Malpighian tubules and heads of both sugar-fed and blood-fed adult female mosquitoes. The expression level of AaAtg8 mRNA increased in the midgut and abdominal carcass following being challenged with Listeria monocytogenes. To investigate the role of AaAtg8 in the innate immune responses of Ae. albopictus, AaAtg8 gene-silenced adult mosquitoes were challenged by injection or by being fed microorganisms in blood. High mortality rates were observed in mosquitoes in which AaAtg8 was silenced after challenges of microorganisms to the host by blood feeding. This suggests that Atg8-autophagy plays a critical role in the gut immunity in Ae. albopictus.
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Aedes/genética , Aedes/inmunología , Familia de las Proteínas 8 Relacionadas con la Autofagia/genética , Interacciones Huésped-Patógeno , Inmunidad Mucosa/genética , Mucosa Intestinal/inmunología , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiología , Secuencia de Aminoácidos , Animales , Familia de las Proteínas 8 Relacionadas con la Autofagia/química , Secuencia de Bases , Interacciones Huésped-Patógeno/genética , Interacciones Huésped-Patógeno/inmunología , Inmunomodulación/genética , ARN Mensajero/genéticaRESUMEN
Relish, a transcription factor, is a critical downstream component of the immune deficiency (Imd) pathway and regulates host defense against bacterial infection by mediating antimicrobial peptide (AMP) synthesis. Understanding the immunological function of the mealworm beetle, Tenebrio molitor Relish (TmRelish) will be instructive in understanding insect immunity. In the present study, full-length ORF of TmRelish was retrieved from T. molitor-expressed sequence tags and RNA-seq database. The predicted TmRelish amino acid sequence contained an N-terminal Rel-homology domain; an Ig-like, plexin, and transcription factor domain; ankyrin repeat motifs; a nuclear localization signal; and a C-terminal death domain and shared the highly conserved structure of the Relish proteins of other insect species. TmRelish mRNA was detected in all developmental stages of the insect; however, the highest levels were detected in the larval gut tissue and adult hemocytes. TmRelish mRNA level was upregulated in the fat body, hemocyte, and gut tissue 9 h after infection of T. molitor larvae by the gram-negative bacteria, Escherichia coli. Furthermore, TmRelish knockdown led to significantly higher mortality of the E. coli-infected larvae, and significantly lower mortality of larvae infected with Staphylococcus aureus or Candida albicans. To elucidate the possible cause of mortality, we measured AMP transcription in the fat body, hemocytes, gut, and Malpighian tubules (MTs) of T. molitor larvae. TmRelish knockdown suppressed the expression of nine AMP genes in the larval fat body and gut tissue during E. coli infection, suggesting that TmRelish positively regulates AMP expression in both immune-related tissues, in response to E. coli challenge. Furthermore, negative regulation of some AMPs by TmRelish in the MTs, gut and hemocytes in response to C. albicans infection suggests a crosstalk between the Toll and Imd pathways.
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Autophagy-related gene-6 (Beclin-1 in mammals) plays a pivotal role in autophagy and is involved in autophagosome formation and autolysosome maturation. In this study, we identified and characterized the autophagy-related gene-6 from Tenebrio molitor (TmAtg6) and analyzed its functional role in the survival of the insect against infection. The expression of TmAtg6 was studied using qRT-PCR for the assessment of the transcript levels at various developmental stages in the different tissues. The results showed that TmAtg6 was highly expressed at the 6-day-old pupal stage. Tissue-specific expression studies revealed that TmAtg6 was highly expressed in the hemocytes of late larvae. The induction patterns of TmAtg6 in different tissues of T. molitor larvae were analyzed by injecting Escherichia coli, Staphylococcus aureus, Listeria monocytogenes, or Candida albicans. The intracellular Gram-positive bacteria, L. monocytogenes, solely induced the expression of TmAtg6 in hemocytes at 9 h-post-injection, whilst in the fat body and gut, bimodal expression times were observed. RNAi-mediated knockdown of the TmAtg6 transcripts, followed by a challenge with microbes, showed a significant reduction in larval survival rate against L. monocytogenes. Taken together, our results suggest that TmAtg6 plays an essential role in anti-microbial defense against intracellular bacteria.
Asunto(s)
Antiinfecciosos/farmacología , Beclina-1/metabolismo , Beclina-1/farmacología , Listeria monocytogenes/efectos de los fármacos , Tenebrio/metabolismo , Animales , Autofagia , Beclina-1/genética , Candida albicans , Escherichia coli , Regulación de la Expresión Génica , Silenciador del Gen , Hemocitos , Larva/metabolismo , Larva/microbiología , Interferencia de ARN/fisiología , Alineación de Secuencia , Staphylococcus aureus , Tasa de Supervivencia , Tenebrio/genética , Tenebrio/microbiologíaRESUMEN
In this study, the sintering behaviors of Nb-6Mo-20Si-3Cr (at percentage) in situ composite powders were studied. The Nb alloy powder was fabricated by a hydrogenation-dehydrogenation method, and both the alloy ingot and powders consisted of two phases: An Nb metal phase and the α-Nb5Si3 phase. Consolidation of the alloy powders was performed at 1500, 1600, and 1700 °C using spark plasma sintering, and the microstructures and phases formed at various sintering temperatures were analyzed. Micropores were observed in the compact sintered at 1500 °C due to the lack of complete densification at that temperature. The densification was completed at 1600 °C and the microstructure was slightly coarsened at 1700 °C compared to the microstructure of the compact sintered at 1600 °C. The microstructures prepared by the powder metallurgy method were finer than the microstructure of the ingot prepared by the casting method. The phase formation behavior varied according to the sintering temperature. Specifically, the α-Nb5Si3 phase, which is a stable structure of the Nb5Si3 phase at a low temperature, was transformed to the ß-Nb5Si3 phase (which is stable at a high temperature) with an increasing sintering temperature.
RESUMEN
Dorsal, a member of the nuclear factor-kappa B (NF-κB) family of transcription factors, is a critical downstream component of the Toll pathway that regulates the expression of antimicrobial peptides (AMPs) against pathogen invasion. In this study, the full-length ORF of Dorsal was identified from the RNA-seq database of the mealworm beetle Tenebrio molitor (TmDorX2). The ORF of TmDorX2 was 1,482 bp in length, encoding a polypeptide of 493 amino acid residues. TmDorX2 contains a conserved Rel homology domain (RHD) and an immunoglobulin-like, plexins, and transcription factors (IPT) domain. TmDorX2 mRNA was detected in all developmental stages, with the highest levels observed in 3-day-old adults. TmDorX2 transcripts were highly expressed in the adult Malpighian tubules (MT) and the larval fat body and MT tissues. After challenging the larvae with Staphylococcus aureus and Escherichia coli, the TmDorX2 mRNA levels were upregulated 6 and 9 h post infection in the whole body, fat body, and hemocytes. Upon Candida albicans challenge, the TmDorX2 mRNA expression were found highest at 9 h post-infection in the fat body. In addition, TmDorX2-knockdown larvae exposed to E. coli, S. aureus, or C. albicans challenge showed a significantly increased mortality rate. Furthermore, the expression of 11 AMP genes was downregulated in the gut and fat body of dsTmDorX2-injected larvae upon E. coli challenge. After C. albicans and S. aureus challenge of dsTmDorX2-injected larvae, the expression of 11 and 10 AMPs was downregulated in the gut and fat body, respectively. Intriguingly, the expression of antifungal transcripts TmTenecin-3 and TmThaumatin-like protein-1 and -2 was greatly decreased in TmDorX2-silenced larvae in response to C. albicans challenge, suggesting that TmDorX2 regulates antifungal AMPs in the gut in response to C. albicans infection. The AMP expression profiles in the fat body, hemocytes, gut, and MTs suggest that TmDorX2 might have an important role in promoting the survival of T. molitor larvae against all mentioned pathogens.