Diffusion-tensor magnetic resonance imaging as a non-invasive assessment of extracellular matrix remodeling in lumbar paravertebral muscles of rats with sarcopenia.

BACKGROUND: Extracellular matrix (ECM) remodeling in skeletal muscle is a significant factor in the development of sarcopenia. This study aims to evaluate changes in ECM remodeling in the lumbar paravertebral muscles of sarcopenic rats using diffusion-tensor magnetic resonance imaging (DT-MRI) and compare them with histology. METHODS: Twenty 6-month-old female Sprague Dawley rats were randomly divided into the dexamethasone (DEX) group and the control (CON) group. Both groups underwent 3.0T MRI scanning, including Mensa, T2WI, and DT-MRI sequences. The changes in muscle fibers and extracellular matrix (ECM) of the erector spinal muscle were observed using hematoxylineosin and sirius red staining. The expressions of collagen I, III, and fibronectin in the erector spinae were detected by western blot. Pearson correlation analysis was employed to assess the correlation between MRI quantitative parameters and corresponding histopathology markers. RESULTS: The cross-sectional area and fractional anisotropy values of the erector spinae in the DEX group rats were significantly lower than those in the CON group (p < 0.05). Hematoxylin eosin staining revealed muscle fiber atrophy and disordered arrangement in the DEX group, while sirius red staining showed a significant increase in collagen volume fraction in the DEX group. The western blot results indicate a significant increase in the expression of collagen I, collagen III, and fibronectin in the DEX group (p < 0.001 for all). Correlation coefficients between fractional anisotropy values and collagen volume fraction, collagen I, collagen III, and fibronectin were - 0.71, -0.94, -0.85, and - 0.88, respectively (p < 0.05 for all). CONCLUSIONS: The fractional anisotropy value is strongly correlated with the pathological collagen volume fraction, collagen I, collagen III, and fibronectin. This indicates that DT-MRI can non-invasively evaluate the changes in extracellular matrix remodeling in the erector spinal muscle of sarcopenia. It provides a potential imaging biomarker for the diagnosis of sarcopenia.

Salvianolic Acid A Improves Rat Kidney Injury by Regulating MAPKs and TGF-ß1/Smads Signaling Pathways.

Salvianolic acid A (SAA) is one of the major components in Salvia miltiorrhiza Bge., with various pharmacological activities, and is likely to be a promising agent for the treatment of kidney diseases. The purpose of this study was to explore the protective effect and mechanisms of SAA on kidney disease. In this study, the improvement effects of SAA (10, 20, 40 mg/kg, i.g.) on kidney injury rats were investigated by detecting the levels of KIM-1, NGAL in serum and UP in the urine of AKI model rats established with gentamicin, as well as the levels of SCr and UREA in serum and IL-6, IL-12, MDA and T-SOD in the kidneys of CKD model rats established with 5/6 nephrectomy. HE and Masson staining were used to observe the histopathological changes in the kidney. Network pharmacology and Western blotting were used to explore the mechanism of SAA in improving kidney injury. The results showed that SAA improved kidney function in kidney injury rats by reducing the kidney index and pathological injury by HE and Masson staining, reducing the levels of KIM-1, NGAL and UP in AKI rats and UREA, SCr and UP in CKD rats, as well as exerting anti-inflammatory and anti-oxidative stress effects by inhibiting the release of IL-6 and IL-12, reducing MDA and increasing T-SOD. Western blotting results showed that SAA significantly reduced the phosphorylation levels of ERK1/2, p38, JNK and smad2/3, and the expression of TLR-4 and smad7. In conclusion, SAA plays a significant role in improving kidney injury in rats and the mechanism may be achieved by regulating the MAPKs and TGF-ß1/smads signaling pathways.

[Effect of parental training based on Early Start Denver Model combined with intensive training on children with autism spectrum disorder and its impact on parenting stress].

OBJECTIVE: To explore the effect of parental training based on the Early Start Denver Model (ESDM) combined with intensive training on the treatment outcome of children with autism spectrum disorder (ASD) and its impact on parenting stress. METHODS: Seventy children aged 2-5 years who were diagnosed with ASD were enrolled in the study. They were divided into an ESDM group and a parental training group by the random number table method (n=35 each). The ESDM group received intensive training based on ESDM. In addition to intensive ESDM-based training, parents of the children in the parental training group received ESDM skills training. Both groups were assessed by Autism Behavior Checklist (ABC), Childhood Autism Rating Scale (CARS), Autism Treatment Evaluation Checklist (ATEC) and Parenting Stress Index-Short Form (PSI-SF) before and after the intervention of 3 months. RESULTS: After 3 months of intervention, the total scores of ABC, CARS and ATEC were both significantly decreased in the two groups (P<0.05). There was no significant difference in the total scores of ABC, CARS and ATEC between the two groups before and after intervention (P>0.05). The change between ABC, CARS and ATEC total scores in the two groups had no significant difference (P>0.05). After 3 months of intervention, the total scores of PSI-SF were both significantly decreased in the two groups (P<0.05). The difficult child sub-scale scores in PSI-SF were significantly decreased in the ESDM group (P<0.05). While three sub-scale scores of parent distress, parent-child dysfunctional interaction and difficult child in PSI-SF were significantly decreased in the parental training group (P<0.05). Before and after intervention of 3 months, no significant difference was found in PSI-SF total scores between the two groups. Compared with the ESDM group, the change between PSI-SF total scores and two sub-scales of PSI-SF (parent distress and difficult child) were significantly bigger in the parental training group (P<0.05). CONCLUSIONS: Both the combination of intensive training and parent training based on ESDM and ESDM intensive training alone can improve the core symptoms of children with ASD aged 2-5 years and relieve the parenting stress, however, the former is more effective in relieving parenting stress.

Sphingobacterium athyrii sp. nov., a cellulose- and xylan-degrading bacterium isolated from a decaying fern (Athyrium wallichianum Ching).

Assessment of the bacterial diversity associated with a decaying fern, Athyrium wallichianum Ching, revealed the presence of a novel bacterial strain named M46T. It was Gram-stain-negative, rod-shaped, non-motile and aerobic with cellulose and xylan degradation abilities. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain M46T was affiliated to the genus Sphingobacterium, exhibiting the highest sequence similarity of 97.9 % to Sphingobacterium ginsenosidimutans THG 07T, Sphingobacterium canadense CR11T and Sphingobacterium detergens6.2 ST. Multilocus sequence analysis (MLSA) based on concatenated sequences of the rpoB, cpn60 and 16S rRNA genes showed that strain M46T clustered together with S. canadense CR11T. The genome of strain M46T had a G+C content of 40.6 mol% and chromosome of 6 853 865 bp. Average nucleotide identity (ANI) between strain M46T and S. detergens 6.2 ST and S. siyangense SY1T was 85.1 and 78.1 %, respectively. DNA-DNA relatedness values among strain M46T and other closely related Sphingobacterium species were <70 %. ANI and DNA-DNA relatedness findings strongly supported M46T as a putative novel strain of Sphingobacterium. The predominant fatty acids of strain M46T were iso-C15 : 0, summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) and iso-C17 : 0 3-OH, and MK-7 was the dominant isoprenoid quinone. The polar lipid profile of strain M46T contained phosphatidylethanolamine as the dominant component, while minor amounts of phosphoglycolipid, one unidentified aminophospholipid, two unidentified phospholipids and four unidentified lipids were also detected. Based on 16S rRNA gene sequence similarities, MLSA results, genomic characteristics, and phenotypic and biochemotaxonomic analyses, strain M46T is considered to represent a novel species in the genus Sphingobacterium, for which the name Sphingobacterium athyrii sp. nov. is proposed. The type strain is M46T (=CGMCC 1.13466T=JCM 32543T).

Characterization of the hot pepper (Capsicum frutescens) fruit ripening regulated by ethylene and ABA.

BACKGROUND: Ripening of fleshy fruits has been classically defined as climacteric or non-climacteric. Both types of ripening are controlled by plant hormones, notably by ethylene in climacteric ripening and by abscisic acid (ABA) in non-climacteric ripening. In pepper (Capsicum), fruit ripening has been widely classified as non-climacteric, but the ripening of the hot pepper fruit appears to be climacteric. To date, how to regulate the hot pepper fruit ripening through ethylene and ABA remains unclear. RESULTS: Here, we examined ripening of the hot pepper (Capsicum frutescens) fruit during large green (LG), initial colouring (IC), brown (Br), and full red (FR) stages. We found a peak of ethylene emission at the IC stage, followed by a peak respiratory quotient at the Br stage. By contrast, ABA levels increased slowly before the Br stage, then increased sharply and reached a maximum level at the FR stage. Exogenous ethylene promoted colouration, but exogenous ABA did not. Unexpectedly, fluridone, an inhibitor of ABA biosynthesis, promoted colouration. RNA-sequencing data obtained from the four stages around ripening showed that ACO3 and NCED1/3 gene expression determined ethylene and ABA levels, respectively. Downregulation of ACO3 and NCED1/3 expression by virus-induced gene silencing (VIGS) inhibited and promoted colouration, respectively, as evidenced by changes in carotenoid, ABA, and ethylene levels, as well as carotenoid biosynthesis-related gene expression. Importantly, the retarded colouration in ACO3-VIGS fruits was rescued by exogenous ethylene. CONCLUSIONS: Ethylene positively regulates the hot pepper fruit colouration, while inhibition of ABA biosynthesis promotes colouration, suggesting a role of ABA in de-greening. Our findings provide new insights into processes of fleshy fruit ripening regulated by ABA and ethylene, focusing on ethylene in carotenoid biosynthesis and ABA in chlorophyll degradation.

[Preliminary application of Early Start Denver Model in children with autism spectrum disorder].

OBJECTIVE: To investigate the clinical effect of the Early Start Denver Model (ESDM) in children with autism spectrum disorder (ASD). METHODS: Forty children aged 2-5 years who were diagnosed with ASD from September 2017 to January 2018 were enrolled in the study and were randomly divided into conventional intervention group and ESDM intervention group (n=20 each). Both groups were assessed by the Aberrant Behavior Checklist (ABC), Childhood Autism Rating Scale (CARS), and Clinical Global Impression-Severity (CGI-S) scale before intervention and by the ABC, CARS, CGI-S scale, and Clinical Global Impression-Improvement (CGI-I) scale after 3 months of intervention. RESULTS: After 3 months of intervention, the total scores of ABC and CARS were both significantly decreased in the two groups (P<0.01); the scores on the social withdrawal and hyperactivity subscales of ABC were significantly decreased in the conventional intervention group (P<0.01), and the scores on the mood swings, social withdrawal, hyperactivity, and stereotyped behavior subscales of ABC were significantly decreased in the ESDM intervention group (P<0.01). Compared with the conventional intervention group, the ESDM intervention group had significantly greater changes in total score of ABC, scores on three subscales of ABC (mood swings, social withdrawal, and hyperactivity), and total score of CARS after intervention (P<0.05). After 3 months of intervention, the CGI-I scoring system showed that the disease improvement was significantly better in the ESDM intervention group than in the conventional intervention group (P<0.05). CONCLUSIONS: Both conventional intervention and ESDM intervention can improve the social withdrawal and hyperactivity in children with ASD aged 2 to 5 years, but ESDM is more effective in improving the aberrant behavior of children with ASD.

The dual functions of WLIM1a in cell elongation and secondary wall formation in developing cotton fibers.

LIN-11, Isl1 and MEC-3 (LIM)-domain proteins play pivotal roles in a variety of cellular processes in animals, but plant LIM functions remain largely unexplored. Here, we demonstrate dual roles of the WLIM1a gene in fiber development in upland cotton (Gossypium hirsutum). WLIM1a is preferentially expressed during the elongation and secondary wall synthesis stages in developing fibers. Overexpression of WLIM1a in cotton led to significant changes in fiber length and secondary wall structure. Compared with the wild type, fibers of WLIM1a-overexpressing plants grew longer and formed a thinner and more compact secondary cell wall, which contributed to improved fiber strength and fineness. Functional studies demonstrated that (1) WLIM1a acts as an actin bundler to facilitate elongation of fiber cells and (2) WLIM1a also functions as a transcription factor to activate expression of Phe ammonia lyase-box genes involved in phenylpropanoid biosynthesis to build up the secondary cell wall. WLIM1a localizes in the cytosol and nucleus and moves into the nucleus in response to hydrogen peroxide. Taken together, these results demonstrate that WLIM1a has dual roles in cotton fiber development, elongation, and secondary wall formation. Moreover, our study shows that lignin/lignin-like phenolics may substantially affect cotton fiber quality; this finding may guide cotton breeding for improved fiber traits.

SDF1-CXCR4 signaling contributes to persistent pain and hypersensitivity via regulating excitability of primary nociceptive neurons: involvement of ERK-dependent Nav1.8 up-regulation.

BACKGROUND: Pain is one critical hallmark of inflammatory responses. A large number of studies have demonstrated that stromal cell-derived factor 1 (SDF1, also named as CXCL12) and its cognate receptor C-X-C chemokine receptor type 4 (CXCR4) play an important role in immune reaction and inflammatory processes. However, whether and how SDF1-CXCR4 signaling is involved in inflammatory pain remains unclear. METHODS: Under the intraplantar (i.pl.) bee venom (BV) injection-induced persistent inflammatory pain state, the changes of SDF1 and CXCR4 expression and cellular localization in the rat dorsal root ganglion (DRG) were detected by immunofluorescent staining. The role of SDF1 and CXCR4 in the hyperexcitability of primary nociceptor neurons was assessed by electrophysiological recording. Western blot analysis was used to quantify the DRG Nav1.8 and phosphorylation of ERK (pERK) expression. Behavioral tests were conducted to evaluate the roles of CXCR4 as well as extracellular signal-regulated kinase (ERK) and Nav1.8 in the BV-induced persistent pain and hypersensitivity. RESULTS: We showed that both SDF1 and CXCR4 were dramatically up-regulated in the DRG in i.pl. BV-induced inflammatory pain model. Double immunofluorescent staining showed that CXCR4 was localized in all sizes (large, medium, and small) of DRG neuronal soma, while SDF1 was exclusively expressed in satellite glial cells (SGCs). Electrophysiological recording showed that bath application with AMD3100, a potent and selective CXCR4 inhibitor, could reverse the hyperexcitability of medium- and small-sized DRG neurons harvested from rats following i.pl. BV injection. Furthermore, we demonstrated that the BV-induced ERK activation and Nav1.8 up-regulation in the DRG could be blocked by pre-antagonism against CXCR4 in the periphery with AMD3100 as well as by blockade of ERK activation by intrathecal (i.t.) or intraplantar (i.pl.) U0126. At behavioral level, the BV-induced persistent spontaneous pain as well as primary mechanical and thermal hypersensitivity could also be significantly suppressed by blocking CXCR4 and Nav1.8 in the periphery as well as by inhibition of ERK activation at the DRG level. CONCLUSIONS: The present results suggest that peripheral inflammatory pain state can trigger over release of SDF1 from the activated SGCs in the DRG by which SGC-neuronal cross-talk is mediated by SDF1-CXCR4 coupling that result in subsequent ERK-dependent Nav1.8 up-regulation, leading to hyperexcitability of tonic type of the primary nociceptor cells and development and maintenance of persistent spontaneous pain and hypersensitivity.

Selective class I histone deacetylase inhibitors suppress persistent spontaneous nociception and thermal hypersensitivity in a rat model of bee venom-induced inflammatory pain.

To confirm whether class I histone deacetylase inhibitors (HDACIs) are effective in relief of peripheral inflammatory pain, the effects of two selective inhibitors, MS-275 and MGCD0103, were studied in rats inflamed by subcutaneous (s.c.) injection of bee venom (BV). The BV test is characterized by displaying both persistent spontaneous nociception (PSN) and primary hypersensitivity. Intrathecal (i.t.) pre-treatment of either MS-275 or MGCD0103 with a single dose of 60 nmol/20 µL resulted in profound suppression of both PSN and primary thermal hypersensitivity but without significant influence upon the primary mechanical hypersensitivity and mirror-image thermal hypersensitivity. Moreover, the up-regulation of both HDAC1 and HDAC2 induced by s.c. BV injection was completely suppressed by i.t. pre-treatment of MS-275. The present results provide with another new line of evidence showing involvement of epigenetic regulation of chromatin structure by HDAC1/2-mediated histone hypoacetylation in the BV-induced PSN and thermal hypersensitivity and demonstrate the beneficial effects of class I HDACIs in prevention of peripheral inflammatory pain from occurring.

[Empathy for pain: A novel bio-psychosocial-behavioral laboratory animal model].

Empathy, a basic prosocial behavior, is referred to as an ability to understand and share others' emotional state. Generally, empathy is also a social-behavioral basis of altruism. In contrast, impairment of empathy development may be associated with autism, narcissism, alexithymia, personality disorder, schizophrenia and depression. Thus, study of the brain mechanisms of empathy has great importance to not only scientific and clinical advances but also social harmony. However, research on empathy has long been avoided due to the fact that it has been considered as a distinct feature of human beings from animals, leading to paucity of knowledge in the field. In 2006, a Canadian group from McGill University found that a mouse in pain could be shared by its paired cagemate, but not a paired stranger, showing decreased pain threshold and increased pain responses through emotional contagion while they were socially interacting. In 2014, we further found that a rat in pain could also be shared by its paired cagemate 30 min after social interaction, showing long-term decreased pain threshold and increased pain responses, suggesting persistence of empathy for pain (empathic memory). We also mapped out that the medial prefrontal cortex, including the anterior cingulate cortex, prelimbic cortex and infralimbic cortex, is involved in empathy for pain in rats, suggesting that a neural network may be associated with development of pain empathy in the CNS. In the present brief review, we give a brief outline of the advances and challenges in study of empathy for pain in humans and animals, and try to provide a novel bio-psychosocial-behavioral model for study of pain and its emotional comorbidity using laboratory animals.

Salvianolic acid A provides neuroprotective effects on cerebral ischemia-reperfusion injury in rats via PKA/CREB/c-Fos signaling pathway.

BACKGROUND: Cerebral ischemia-reperfusion injury (CIRI) is a phenomenon that pathological injury of ischemic brain tissue is further aggravated after the restoration of blood supply. The complex pathological mechanism of CIRI has led to the failure of multiple neuroprotective agents in clinical studies. Salvianolic acid A (SAA) is a neuroprotective extract from Salvia miltiorrhiza Bge., with significant pharmacological activities in the treatment of brain injury. However, the neuroprotective mechanisms of SAA remain unclear. PURPOSE: To explore the potential protective effect of SAA on CIRI and its mechanism, and to provide experimental basis for the research of new drugs for CIRI. STUDY DESIGN: A model of transient middle cerebral artery occlusion (tMCAO) in rats was used to simulate clinical CIRI, and the neuroprotective effect of SAA on tMCAO rats was investigated within 14 days after reperfusion. The improvement effects of SAA on cognitive impairment of tMCAO rats were investigated by behavioral tests from days 7-14. Finally, the neuroprotective mechanism of SAA was investigated on day 14. METHODS: The neuroprotective effects and mechanism of SAA were investigated by behavioral tests, HE and TUNEL staining, RNA sequence (RNA-seq) analysis and Western blot in tMCAO rats. RESULTS: The brain protective effects of SAA were achieved by alleviating cerebral infarction, cerebral edema, cerebral atrophy and nerve injury in tMCAO rats. Meanwhile, SAA could effectively improve the cognitive impairment and pathological damage of hippocampal tissue, and inhibit cell apoptosis in tMCAO rats. Besides, SAA could provide neuroprotective effects by up-regulating the expression of Bcl-2, inhibiting the activation of Caspase 3, and regulating PKA/CREB/c-Fos signaling pathway. CONCLUSION: SAA can significantly improve brain injury and cognitive impairment in CIRI rats, and this neuroprotective effect may be achieved through the anti-apoptotic effect and the regulation of PKA/CREB/c-Fos signaling pathway.

[Distribution Characteristics of Rh Phenotype and Feasibility of Compatible Blood Transfusion in Pregnant and Postpartum Women].

OBJECTIVE: To analyze the distribution characteristics of Rh phenotype in pregnant and postpartum women in Chongqing area, and to explore the clinical significance of Rh phenotype in pregnant and postpartum women and the feasibility of Rh phenotype compatible blood transfusion. METHODS: The ABO blood group and Rh phenotype of 65 161 pregnant and postpartum women were detected by microcolumn gel method, and 48 122 males in the same period were taken as controls. The data were analyzed by Chi-square test. RESULTS: There were 112 870 cases (99.64%) of RhD+ in 113 283 samples. In RhD+ cases, CCDee (48.39%) and CcDEe (32.88%) were the main phenotypes. The first case of D-- phenotype in Chongqing area was detected. 413 cases (0.36%) of RhD- were detected, with ccdee (52.78%) and Ccdee (33.41%) as the main phenotypes. Compared with RhD- group, RhD+ group showed statistically significant difference in Rh phenotype distribution (P < 0.01). Among 65 161 maternal samples, the positive rate of 5 antigens of Rh blood group from high to low was D > e > C > c > E, and there was no significant difference compared with male samples (P >0.05). There was no significant difference in the distribution of Rh phenotype between males and pregnant/postpartum women, as well as between pregnant/postpartum women with different ABO blood groups (P >0.05). In pregnant and postpartum women, there was no significant difference in distribution of Rh phenotype among the normal pregnancy population, the population with adverse pregnancy history, the population using human assisted reproductive technology (ART) and the population with infertility (P >0.05). There was no significant difference in the distribution of Rh phenotype between the 4 populations mentioned above and the inpatients in the local general Grade A hospitals and the blood donors (P >0.05). In RhD positive pregnant and postpartum women, the probability of finding compatible blood for CcDEe phenotype was 100%, the probability of finding compatible blood for CCDee, CcDee and CCDEe phenotypes was 45%-60%, the probability of finding compatible blood for ccDEE, ccDEe and CcDEE phenotypes was 5%-10%, and the probability of finding compatible blood for other phenotypes was lower than 0.5%. The supply of blood with CCDee and ccDEE phenotypes can meet the compatible transfusions requirements of 7 Rh phenotypes in more than 99% of patients. CONCLUSION: Rh phenotype detection should be carried out for pregnant and postpartum women, and it is feasible to carry out Rh phenotype-matched or compatible blood transfusion for pregnant and postpartum women who need blood transfusion.

[Serological Characteristics and Clinical Significance of Irregular Antibodies in Pregnant Women].

OBJECTIVE: To understand the serological characteristics of irregular antibodies in pregnant women and explore their clinical significance. METHODS: From January 2017 to March 2022, 151 471 pregnant women in Women and Children's Hospital of Chongqing Medical University were enrolled in this study, microcolumn gel card test was used for irregular antibody screening, and antibody specificity identification was further performed in some antibody-positive subjects. RESULTS: The positive rate of irregular antibody screening in the enrolled pregnant women was 0.91% (1 375/151 471), 0.23% (355/151 471) was detected in the first trimester, 0.05% (71/151 471) in the second trimester, and 0.63% (949/151 471) in the third trimester. The positive rate of irregular antibody screening in the third trimester was significantly higher than that in the first and second trimester, and a significant increase in the number of positive cases was found in the third trimester than that in the second trimester. The analysis of agglutination intensity of 1 375 irregular antibody screening positive results showed that the weakly positive agglutination intensity accounted for 50.11% (689/ 1 375), which was the highest, the suspicious positive was 18.69% (257/1 375), and the positive was 31.20% (429/1 375). The significant difference in distribution of agglutination intensity was not observed between the first trimester group and the second trimester group, however, in the third trimester, the proportion of suspicious positive and weakly positive was lower than the first trimester, while, the proportion of positive was higher than the first trimester, and the difference was statistically significant (P < 0.001). Among the irregular antibody screening positive pregnant women, the proportion of pregnant women with pregnancy number ≥ 2 was significantly higher than that with pregnancy ≤ 1. Among 60 pregnant women who underwent antibody identification, the distributions of the antibodies were as follows: Rh blood group system accounted for 23.33% (14/60), Lewis system 43.33% (26/60), Kidd system 3.33% (2/60), MNS system 16.67% (10/60), P1PK system 1.67% (1/60), autoantibodies 1.67% (1/60), and 4 cases was unable to identify (6.67%, 4/60). Among specific antibodies, the anti-Lea was the most common (30.00%), followed by anti-E (16.67%) and anti-M (16.67%). CONCLUSION: The differences of irregular antibody serological characteristics exist in pregnant women from different regions with different genetic backgrounds, understanding the characteristics of irregular antibody in local pregnant women is of great significance for ensuring transfusion safety in pregnant women and preventing hemolytic disease of newborn.

The tobacco BLADE-ON-PETIOLE2 gene mediates differentiation of the corolla abscission zone by controlling longitudinal cell expansion.

The BLADE-ON-PETIOLE (BOP) genes of Arabidopsis (Arabidopsis thaliana) have been shown to play an essential role in floral abscission by specializing the abscission zone (AZ) anatomy. However, the molecular and cellular mechanisms that underlie differentiation of the AZ are largely unknown. In this study, we identified a tobacco (Nicotiana tabacum) homolog of BOP (designated NtBOP2) and characterized its cellular function. In tobacco plants, the NtBOP2 gene is predominantly expressed at the base of the corolla in an ethylene-independent manner. Both antisense suppression of NtBOP genes and overexpression of NtBOP2 in tobacco plants caused a failure in corolla shedding. Histological analysis revealed that the differentiation of the corolla AZ was blocked in the transgenic flowers. This blockage was due to uncontrolled cell elongation at the region corresponding to wild-type AZ. The role of NtBOP2 in regulating cell elongation was further demonstrated in Bright Yellow 2 single cells: perturbation of NtBOP2 function by a dominant negative strategy led to the formation of abnormally elongated cells. Subcellular localization analysis showed that NtBOP2-green fluorescent protein fusion proteins were targeted to both the nucleus and cytoplasm. Yeast two-hybrid, firefly luciferase complementation imaging, and in vitro pull-down assays demonstrated that NtBOP2 proteins interacted with TGA transcription factors. Taken together, these results indicated that NtBOP2 mediated the differentiation of AZ architecture by controlling longitudinal cell growth. Furthermore, NtBOP2 may achieve this outcome through interaction with the TGA transcription factors and via an ethylene-independent signaling pathway.

Type 2C protein phosphatase ABI1 is a negative regulator of strawberry fruit ripening.

Although a great deal of progress has been made toward understanding the role of abscisic acid (ABA) in fruit ripening, many components in the ABA signalling pathway remain to be elucidated. Here, a strawberry gene homologous to the Arabidopsis gene ABI1, named FaABI1, was isolated and characterized. The 1641bp cDNA includes an intact open reading frame that encodes a deduced protein of 546 amino acids, in which putative conserved domains were determined by homology analysis. Transcriptional analysis showed that the levels of FaABI1 mRNA expression declined rapidly during strawberry fruit development as evidenced by real-time PCR, semi-quantitative reverse transcription-PCR, and northern blotting analyses, suggesting that the Ser/Thr protein phosphatase PP2C1 encoded by FaABI1 may be involved in fruit ripening as a negative regulator. The results of Tobacco rattle virus-induced gene silencing and PBI121 vector-mediated overexpression suggested that the down- and up-regulation of FaABI1 mRNA expression levels in degreening strawberry fruit could promote and inhibit ripening, respectively. Furthermore, alteration of FaABI1 expression could differentially regulate the transcripts of a set of both ABA-responsive and ripening-related genes, including ABI3, ABI4, ABI5, SnRK2, ABRE1, CHS, PG1, PL, CHI, F3H, DFR, ANS, and UFGT. Taken together, the data provide new evidence for an important role for ABA in regulating strawberry fruit ripening in the processes of which the type 2C protein phosphatase ABI1 serves as a negative regulator. Finally, a possible core mechanism underlying ABA perception and signalling transduction in strawberry fruit ripening is discussed.

Cloning, expression and characterization of antimicrobial porcine ß defensin 1 in Escherichia coli.

Porcine ß defensin 1 (pBD1) is a cationic antimicrobial peptide with three pairs of disulfide bonds. When expressed in insect cells, two polypeptides of different length (pBD1(38) and pBD1(42)) accumulated, which differed by N-terminal truncation. However, only pBD1(42) was found in pigs. pBD1(42) had stronger antimicrobial activity than pBD1(38), and thus could be a good candidate as a bactericidal agent for pigs. In this study, pBD1(42) gene, obtained by RT-PCR using the tongue total RNA as a template, was cloned into pET30a expression vector and transformed into Escherichia coli BL21 (DE3) plysS. The recombinant pBD1(42) was expressed after induction by IPTG and purified by His tag affinity column with 90% purity. The recombinant pBD1(42) exhibited antimicrobial activity against both Gram-positive Staphylococcus aureus and Gram-negative E. coli including the multi-resistant E. coli. The minimum inhibitory concentrations (MICs) of recombinant pBD1(42) against tested bacteria were 100 µg/mL for E. coli and 80 µg/mL for S. aureus. In addition, pBD1(42) showed low hemolytic activity and high thermal stability. These properties are relevant for the biotechnological applications of the peptide.

Paenibacillus typhae sp. nov., isolated from roots of Typha angustifolia L.

A Gram-stain-positive, facultatively anaerobic and rod-shaped bacterium, designated strain xj7(T), was isolated from roots of Typha angustifolia L. growing in Beijing Cuihu Wetland, China. The isolate was identified as a member of the genus Paenibacillus based on phenotypic characteristics and phylogenetic inference. The novel strain was spore-forming, motile, catalase-positive and oxidase-negative. Optimal growth of strain xj7(T) occurred at 28-30 °C and pH 7.0-7.5. Diphosphatidylglycerol was the most abundant polar lipid and occurred along with phosphatidylglycerol, phosphatidylethanolamine, one unknown phospholipid and three unknown aminophospholipids. The diamino acid found in the cell-wall peptidoglycan was meso-diaminopimelic acid. The predominant isoprenoid quinone was MK-7. The major fatty acid components were anteiso-C15 : 0 (56.1 %), iso-C16 : 0 (9.1 %), C16 : 0 (8.0 %), iso-C14 : 0 (6.3 %) and iso-C15 : 0 (5.1 %). The G+C content of genomic DNA was 47.9 mol%. Phylogenetic analysis based on the 16S rRNA gene sequence showed that strain xj7(T) fell within the evolutionary radiation encompassed by the genus Paenibacillus, its closest neighbours were Paenibacillus borealis KK19(T) (97.5 %) and Paenibacillus durus DSM 1735(T) (97.1 %). However, the DNA-DNA relatedness values between strain xj7(T) and P. borealis KK19(T) and between strain xj7(T) and P. durus DSM 1735(T), were both 35 %. Based on phenotypic, chemotaxonomic and phylogenetic properties, strain xj7(T) is considered to represent a novel species of the genus Paenibacillus, for which the name Paenibacillus typhae sp. nov. is proposed. The type strain is xj7(T) ( = CGMCC 1.11012(T) = DSM 25190(T)).

Massilia namucuonensis sp. nov., isolated from a soil sample.

A Gram-staining-negative, rod-shaped and non-spore-forming bacterium, designated strain 333-1-0411(T), was isolated from a soil sample collected from Namucuo, Tibet Autonomous Region, China and characterized in a taxonomic study using a polyphasic approach. The major fatty acid components of strain 333-1-0411(T) were summed feature 3 (C(16 : 1)ω7c and/or C(16 : 1)ω6c) and C(16 : 0); its major polar lipids were phosphatidylethanolamine, diphosphatidylglycerol and phosphatidylglycerol. Q-8 was the dominant ubiquinone, and the G+C content of the genomic DNA was 66.7 mol%. A phylogenetic tree based on 16S rRNA gene sequences showed that strain 333-1-0411(T) fell within the evolutionary radiation encompassed by the genus Massilia. The 16S rRNA gene sequence similarities between strain 333-1-0411(T) and recognized species of the genus Massilia ranged from 95.4 % to 97.2 %, and the most closely related strains were Massilia flava Y9(T) (97.2 %) and Massilia albidiflava 45(T) (97.0 %). However, the DNA-DNA relatedness values between strain 333-1-0411(T) and M. flava Y9(T) and M. albidiflava 45(T) were 20.2 % and 27.2 %, respectively. Based on the phenotypic, chemotaxonomic and phylogenetic properties, strain 333-1-0411(T) is considered to represent a novel species of the genus Massilia, for which the name Massilia namucuonensis sp. nov. is proposed. The type strain is 333-1-0411(T) (= CGMCC 1.11014(T) = DSM 25159(T)).

Burkholderia grimmiae sp. nov., isolated from a xerophilous moss (Grimmia montana).

A Gram-staining-negative, rod-shaped, non-spore-forming bacterium, designated strain R27(T), was isolated from the moss Grimmia montana, collected from Beijing Songshan National Nature Reserve, China, and characterized by using a polyphasic taxonomic approach. The predominant fatty acids of strain R27(T) were C18:1ω7c (33.6%), C16:0 (16.3%), summed feature 3 (C16:1ω7c and/or C16:1ω6c; 15.8%) and C17:0 cyclo (8.7%) and its major polar lipids were phosphatidylethanolamine, phosphatidylglycerol, three uncharacterized aminolipids and an unknown phospholipid. Strain R27(T) contained Q-8 as the dominant isoprenoid quinone and the G+C content of its genomic DNA was 64.6 mol%. On the basis of 16S rRNA gene sequence comparison, strain R27(T) showed 99.1% similarity to the closest related type strain, Burkholderia zhejiangensis OP-1(T), and 97.6% similarity to Burkholderia glathei ATCC 29195(T). However, the DNA-DNA relatedness between strain R27(T) and B. zhejiangensis CCTCC AB 2010354(T) and B. glathei ATCC 29195(T) was 10.2 and 14.9%, respectively. Based on 16S rRNA and rpoB gene sequence similarities and phenotypic and chemotaxonomic data, strain R27(T) is considered to represent a novel species of the genus Burkholderia, for which the name Burkholderia grimmiae sp. nov. is proposed. The type strain is R27(T) (=CGMCC 1.11013(T) =DSM 25160(T)).

Over-expression of miR-3584-5p Represses Nav1.8 Channel Aggravating Neuropathic Pain caused by Chronic Constriction Injury.

Nav1.8, a tetrodotoxin-resistant voltage-gated sodium channels (VGSCs) subtype encoded by SCN10A, which plays an important role in the production and transmission of peripheral neuropathic pain signals. Studies have shown that VGSCs may be key targets of MicroRNAs (miRNAs) in the regulation of neuropathic pain. In our study, bioinformatics analysis showed that the targeting relationship between miR-3584-5p and Nav1.8 was the most closely. The purpose of this study was to investigate the roles of miR-3584-5p and Nav1.8 in neuropathic pain. The effects of miR-3584-5p on chronic constriction injury (CCI)-induced neuropathic pain in rats was investigated by intrathecal injection of miR-3584-5p agomir (an agonist, 20 µM, 15 µL) or antagomir (an antagonist, 20 µM, 15 µL). The results showed that over-expression of miR-3584-5p aggravated neuronal injury by hematoxylin-eosin (H&E) staining and mechanical/thermal hypersensitivity in CCI rats. MiR-3584-5p indirectly inhibited the expression of Nav1.8 by up-regulating the expression of key proteins in the ERK5/CREB signaling pathway, and also inhibited the current density of the Nav1.8 channel, changed its channel dynamics characteristic, thereby accelerating the transmission of pain signals, and further aggravating pain. Similarly, in PC12 and SH-SY5Y cell cultures, miR-3584-5p increased the level of reactive oxygen species (ROS) and inhibited mitochondrial membrane potential (Δψm) in the mitochondrial pathway, decreased the ratio of apoptosis-related factor Bcl-2/Bax, and thus promoted neuronal apoptosis. In brief, over-expression of miR-3584-5p aggravates neuropathic pain by directly inhibiting the current density of Nav1.8 channel and altering its channel dynamics, or indirectly inhibiting Nav1.8 expression through ERK5/CREB pathway, and promoting apoptosis through mitochondrial pathway.