[Post-discharge growth of extremely premature infants within corrected age of 24 months]

Objective: To demonstrate the post-discharge catch-up growth of extremely premature infants (EPI) within 24 months of corrected age. Methods: This study retrospectively collected the anthropomorphic measurements of 311 EPI who visited Shenzhen Maternity and Child Healthcare Hospital from August 2013 to April 2020. These infants were stratified according to gestational age at birth (GA): 23-24⁺⁶weeks, 25-26⁺⁶weeks, 27-27⁺⁶weeks; and birth weight:<750 g, 750-999 g, ≥1 000 g. The anthropomorphic measurements, including weight, length, and head circumference for age, were recorded timely from discharge to 24 months of corrected age. And the growth curve stratified by GA and birth weight were fitted in both chronological age and corrected age, which were then compared with the World Health Organization Child Growth Standards for term infant (2006 version), to investigate the catch-up growth pattern of EPI. And appropriate catch-up was defined as the measurements reached the 25^th percentile of WHO growth curve. Results: In these 311 EPI, 184 were males and 127 females, with gestational age of 23-27⁺⁶ weeks and birth weight of 480-1 430 g. Regardless of the GA and birth weight, the growth curves fitted in corrected age failed to overlap with that in chronological age by 24 months of corrected age. The growth velocity of weight, length and head circumference in both corrected and chronological age were all positively correlated with GA and birth weight: the 27-27⁺⁶weeks group showed a preferable growth pattern than the 25-26⁺⁶weeks group, and the curve of the 23-24⁺⁶weeks group was most unfavorable; and the same pattern was observed between the subgroups of different birth weight. Furthermore, the GA had more significant impact on the catch-up growth pattern than birth weight did. When assessed with corrected age curve, the weight and length of both male and female EPIs achieved appropriate catch-up by 24 months, as well as the head circumference of girls; whereas, boys' head circumference reached appropriate catch-up at the corrected age of 9 months, but fell behind the 25^th percentile after that. However, when assessed with chronological age curve, both boys and girls failed to achieve appropriate catch-up in weight, length and head circumference by age 24 months. And no matter in corrected or chronological age, all physical measurements of girls were lower than those of boys. Conclusions: The rapid catch-up growth of EPI happens within 6 months of corrected age. The lower the birth weight and gestational age, the lower the physical measurements at each corresponding month of age, and the longer it takes to achieve appropriate catch-up. Gestational age has a greater impact on the longitudinal catch-up growth than birth weight does. And girls generally grow slower than boys in either correct or actual age. Before 24 months of corrected age, the growth should be assessed with corrected age rather than chronological age.

Correlation of IL-33 gene polymorphism with chronic obstructive pulmonary disease

OBJECTIVE

To explore the correlation between interleukin (IL)-33 gene polymorphism with chronic obstructive pulmonary disease (COPD).

PATIENTS AND METHODS

A total of 210 COPD patients (observation group) and 180 healthy people receiving physical examinations (control group) were included in this study. Clinical information of each subject was collected. Relative levels of inflammation-related factor IL-33 and pulmonary function indexes were determined. Moreover, the polymorphism of IL-33 rs1891385 was detected with the TaqMan-minor groove binder (MGB) probe.

RESULTS

Observation group had a higher level of IL-33 than that of control group (p<0.01), and the forced expiratory volume in 1 second (FEV1)/forced vital capacity (FVC) ratio (%) and FEV1/the predicted value ratio (%) in observation group were lower than those in control group (p<0.05). There were significant differences in the distribution frequencies of genotypes and alleles between the two groups (p<0.05), and genotype AA exhibited a higher level of IL-33, but a lower FEV1/FVC ratio (%) and FEV1/the predicted value ratio (%) than those of genotypes AC and CC (p<0.05).

CONCLUSIONS

IL-33 and pulmonary function test can be used to effectively evaluate the progression of COPD, and the polymorphism of IL-33 rs1891385 is correlated with the onset of COPD.

[Association of sleep-disorders with systemic inflammatory markers and acute exacerbation in chronic obstructive pulmonary disease patients]

Objective: To investigate the association of sleep quality with the levels of systemic inflammatory markers in patients with chronic obstructive pulmonary disease(COPD) and the correlations between the frequency of acute exacerbation of COPD (AECOPD) and Pittsburgh sleep quality index (PSQI). Methods: A total of 198 COPD patients admitted in our hospital from October, 2016 to June, 2017 were screened, and 124 patients were eligible for the study. On the first day of hospitalization, the serum samples and clinical data were collected, including white blood cells, lymphocytes, platelet count, CRP and PSQI. Poor sleep quality was defined as PSQI score >5. Results: The percentage of COPD patients with poor sleep quality was about 68%. Poor sleep quality was positively correlated with the frequency of acute exacerbation in COPD patients. The ratio of neutrophil to lymphocyte (NLR), ratio of platelet to lymphocyte (PLR) and levels of CRP were higher in patients with poor sleep quality than those in the control group. NLR, PLR and CRP in peripheral blood of the patients with poor sleep quality were positively correlated with PSQI score. The CRP levels and PSQI score in COPD patients with poor sleep quality group were positively correlated with the frequency of exacerbations in the past year (r=0.437, r=0.430). Conclusion: A high percentage of COPD patients had poor sleep quality, which was positively correlated with the levels of systemic inflammation as well as the frequency of AECOPD.

Identification of natural recombinants derived from PCV2a and PCV2b

Porcine circovirus type 2 (PCV2) is considered to be the main pathogen in PC-associated diseases, and significantly affects the global pig-producing industry. PCV2 continuously evolves by point mutations and genome recombinations. In the present study, we aimed to further identify recombinant PCV2 strains. We used polymerase chain reaction to detect PCV2 in the carcasses of pigs with suspected infections from different regions of Guangdong Province in China. DNA was extracted from samples with confirmed infection and full- genome amplification, sequencing, phylogenetic tree construction, gene recombination detection, and sequence alignment were performed in gene recombination analysis. Our results show that recombination occurred between the strains SHC (DQ104421) and ZhuJi2003 (AY579893). The recombination resulted in three recombinants: GD003 (KM503044), GD005 (KM487708), and GD008 (KM487709). Further analyses revealed that these novel recombinants appeared to result from recombination between the PCV2a and PCV2b strains, with crossover regions located in ORF2. This study was a comprehensive analysis that used several different methods, which demonstrated that a cluster of PCV2 strains resulted from the same type of inter-genotypic recombination pattern, with a breakpoint in the structural protein coding region. The results of our study provide both information on the recombination mechanism and disease pathogenesis and useful data for the prevention of PCV2 in the swine industry.

First Report of Leaf Blotch Caused by Pestalotiopsis clavispora on Rosa chinensis in China

Rosa chinensis Jacq, a traditional Chinese ornamental flower, is an important landscaping plant in northern China. Since July 2013, leaf blotch symptoms were observed in the Tianjin flower nursery (117°09' E 39°17' N). The garden exhibited 40% disease incidence with observable symptoms on basal leaves that were yellowed from the edge to the inside area on infected leaves, in the shape of a V. Yellow lesions covered one third to one half of the leaf. Yellow halos were observed at the junction of the healthy and diseased tissues. Small tissue pieces from the edges of lesions were disinfected in 70% ethyl alcohol for 30 s and 1% hypochlorite for 1 min, rinsed thrice in sterile water, plated on potato dextrose agar (PDA), and incubated at 25°C in lighted incubator for 4 days. Fungal colonies that developed on PDA were white and cottony with concentric rings. Black and globular acervuli appeared after 10 days at 25°C. Conidia (n = 20), which were fusiform, were 9.20 to 31.31 (avg. 26.5) × 4.83 to 9.11 (avg. 6.9) μm. Conidia of all isolates were five celled. Apical and basal cells were colorless, while the three median cells were dark brown. The single basal appendage of conidia was 2.85 to 16.05 μm in length and the two to three apical appendages were 5.93 to 36.23 μm in length. According to colony and conidia morphology (number of cells, number of appendages), the isolates were initially identified as Pestalotiopsis spp (2). A 525-bp band was produced in a conventional PCR assay. Primers ITS1 (5'TCCGTAGGTGAACCTGCGC3') and ITS4 (5'TCCTCCGCTTATTGATATGC3') were used to amplify and sequence the internal transcribed spacer region of rDNA. A BLAST search of the NCBI databases showed that isolate YJYK-1 had 99% homology with Pestalotiopsis clavispora isolate hz-067 (Accession No. FJ517545.1). Pathogenicity tests of the novel isolate YJYK-1 were conducted by placing agar plugs (5 mm in diameter) from an actively growing colony on PDA on surface-disinfected (70% ethyl alcohol, 30 s) leaves (1). Control leaves were inoculated with sterile PDA plugs. Plants with inoculated leaves (five per treatment) were placed in lighted growth chambers at 25°C for 10 days and watered as needed. Symptoms on inoculated leaves were similar to those previously described in the nursery. Black acervuli were easily found on the necrotic tissues. Control plants did not show any symptoms. Cultures isolated from the lesions were similar to those isolated previously from leaves in the nursery. Koch's postulates were confirmed after re-isolation. Although the diversity of endophytic Pestalotiopsis species and its distribution was investigated and the host plants were also listed in China (3), to our knowledge, this is the first report of P. clavispora causing leaf blotch on rose R. chinensis in China. References: (1) M. I. Ahmed et al. Eur. J. Plant Pathol. 135:619, 2013. (2) J. Y. Lu. Diagnosis of plant diseases. Page 194 in: Pestalotiopsis. J. Y. Lu et al., eds. China Agriculture Press, Beijing, 1995. (3) J. G. Wei et al. Mycosystema 24:481, 2005.

Effects of enrofloxacin on cytochromes P4501A and P4503A in Carassius auratus gibelio (crucian carp)

Currently, although enrofloxacin (EF) as a widely used veterinary medicine has begun to apply to treating fish bacterial infections, the researches on the effects of EF on their main drug metabolic enzymes are limited. To investigate the effects of EF on fish cytochromes P450 (CYPs) 1A and 3A, the enzymatic activities and expressions (mRNA and protein) of crucian carp CYP1A and CYP3A after EF administration were examined. For CYP1A, in the in vivo experiments, EF exhibited potent inhibition on the CYP1A-related ethoxyresorufin-O-deethylase (EROD) activity, as well as CYP1A expressions at both protein and mRNA levels, at 24 h after administration with different EF dosages (3, 10, 30, and 60 mg/kg); Furthermore, CYP1A enzymatic activity and expressions at both protein and mRNA levels decreased more with increasing EF dosages. Additionally, the in vitro experimental results showed that, after incubated with microsomes, EF did not change the EROD activity through interacting directly with CYP1A. For CYP3A, the in vitro and in vivo experimental results demonstrated that EF could inhibit the CYP3A-related erythromycin N-demethylase activity in a time- and dose-dependent manner, while it did not suppress CYP3A expressions at both protein and mRNA levels after administration with EF for a short period (no more than 24 h); however, after injection with EF at a high dose (10 mg/kg) for a long period, the CYP3A protein and mRNA reached their lowest levels at 96 and 48 h, respectively. These results indicate that EF can suppress CYP1A expressions in a dose-dependent manner, thereby inhibiting further its catalytic activity; meanwhile, both the interactions of EF with CYP3A and the expressions decrease (protein and mRNA) caused by EF contribute to the CYP3A inhibition.

Identification of 18 genes encoding necrosis-inducing proteins from the plant pathogen Phytophthora capsici (Pythiaceae: Oomycetes)

Phytophthora capsici is an aggressive plant pathogen that affects solanaceous and cucurbitaceous hosts. Necrosis-inducing Phytophthora proteins (NPPs) are a group of secreted toxins found particularly in oomycetes. Several NPPs from Phytophthora species trigger plant cell death and activate host defense gene expression. We isolated 18 P. capsici NPP genes, of which 12 were active during hypha growth from a Phytophthora stain isolated from pepper (Capsicum annuum) plants in China. The 18 predicted proteins had a sequence homology of 46.26%. The 18 Pcnpp sequences had a conserved GHRHDWE motif and fell into two groups. Eleven sequences in group 1 had two conserved cysteine residues, whereas the other seven sequences in group 2 lacked these two cysteine residues. A phylogenetic tree was constructed on the basis of the alignment of the predicted protein sequences of 52 selected NPP genes from oomycetes, fungi and bacteria from Genbank. The tree did not rigorously follow the taxonomic classification of the species; all the NPPs from oomycetes formed their own clusters, while fungal sequences were grouped into two separate clades, indicating that based on NPPs, we can separate oomycetes from fungi and bacteria, and that expansion of the NPP family was a feature of Phytophthora evolution.

Cigarette smoke enhances {beta}-defensin 2 expression in rat airways via nuclear factor-{kappa}B activation

β-defensin 2 (BD-2), an antimicrobial peptide, participates in airway defence. Cigarette smoke (CS) is a major risk factor for the development of chronic obstructive pulmonary disease. This study mainly aims to investigate the effect of CS on rat BD-2 (rBD-2) expression in rat airways. Rats were exposed to CS and treated with caffeic acid phenethyl ester (CAPE), a nuclear factor (NF)-κB inhibitor, or astragaloside IV (AS-IV), an active ingredient of Astragalus mongholicus. Besides the analysis of bronchoalveolar lavage fluid (BALF) and histological changes after CS exposure, rBD-2 expression was investigated with immunohistochemistry, reverse transcription PCR and ELISA. Total glutathione and nitric oxide (NO) levels in rat lungs were also detected. CS exposure markedly increased rBD-2 immunoreactivity, as well as rBD-2 mRNA and protein levels in rat airways, which were inhibited by CAPE treatment. Moreover, associated airway inflammation induced by CS was demonstrated by histological changes, increased cell counts and pro-inflammatory cytokines in BALF, and NF-κB activation and high levels of total glutathione and NO, which were all reversed by AS-IV in a dose-dependent fashion. In conclusion, CS exposure induces rBD-2 expression in rat airways via a NF-κB-dependent pathway, and AS-IV attenuates CS-induced airway inflammation due to its anti-inflammatory and antioxidant properties, at least partly through NF-κB inactivation.

Ductile titanium alloy with low Poisson's ratio

We report a ductile beta-type titanium alloy with body-centered cubic (bcc) crystal structure having a low Poisson's ratio of 0.14. The almost identical ultralow bulk and shear moduli of approximately 24 GPa combined with an ultrahigh strength of approximately 0.9 GPa contribute to easy crystal distortion due to much-weakened chemical bonding of atoms in the crystal, leading to significant elastic softening in tension and elastic hardening in compression. The peculiar elastic and plastic deformation behaviors of the alloy are interpreted as a result of approaching the elastic limit of the bcc crystal under applied stress.

N-type calcium channels and their regulation by GABAB receptors in axons of neonatal rat optic nerve

Axons of neonatal rat optic nerves exhibit fast calcium transients in response to brief action potential stimulation. In response to one to four closely spaced action potentials, evoked calcium transients showed a fast-rising phase followed by a decay with a time constant of approximately 2-3 sec. By selective staining of axons or glial cells with calcium dyes, it was shown that the evoked calcium transient originated from axons. The calcium transient was caused by influx because it was eliminated when bath calcium was removed. Pharmacological profile studies with calcium channel subtype-specific peptides suggested that 58% of the evoked calcium influx was accounted for by N-type calcium channels, whereas L- and P/Q-type calcium channels had little, if any, contribution. The identity of the residual calcium influx remains unclear. GABA application caused a dramatic reduction of the amplitude of the action potential and the associated calcium influx. When GABAA receptors were blocked by bicuculline, the inhibitory effect of GABA on the action potential was eliminated, whereas that on the calcium influx was not, indicating involvement of GABAB receptors. Indeed, the calcium influx was inhibited by the GABAB receptor agonist baclofen. This baclofen effect was occluded by a previous block of N-type calcium channels and was unaffected by the broad-spectrum K+ channel blocker 4-AP. We conclude that neonatal rat optic nerve axons express N-type calcium channels, which are subjected to regulation by G-protein-coupled GABAB receptors. We suggest that receptor-mediated inhibition of axonal calcium channels plays a protective role in neonatal anoxic and/or ischemic injury.