Echolocation clicks of free-ranging Irrawaddy dolphins (Orcaella brevirostris) in Trat Bay, the eastern Gulf of Thailand.

Little is known about the vocalizations of Irrawaddy dolphins (Orcaella brevirostris) in the Gulf of Thailand. The present study first described the echolocation clicks of Irrawaddy dolphins in Trat Bay, in the eastern Gulf of Thailand, using a broadband hydrophone system. Over 2 h of acoustic recordings were collected during 14-day study periods in December 2017 and December 2018. Several criteria were used to judge if a click was on axis or as close to the acoustic axis as possible. To calculate the distance of dolphins, a low-budget localization method based on arrival time differences between the direct and indirect signals was used in the present study. The clicks had a mean peak-to-peak source level of 192 ± 3 dB re 1 µPa, an energy flux density source level of 131 ± 3 dB re 1 µPa2s, a mean centroid frequency of 98 ± 10 kHz, a mean duration of 16 ± 2 µs, and a -3 dB bandwidth of 79 ± 13 kHz. The click parameters of the Irrawaddy dolphins in Trat Bay were slightly different from the clicks recorded from the dolphins in Sundarbans, Bangladesh. The present study provided a basic description of the click characteristics of Irrawaddy dolphins in Trat Bay, which could contribute to the management and conservation strategies for local Irrawaddy dolphins, and a basic reference for the proper input parameters in passive acoustic monitoring and detection.

In vivo and in vitro effect of hepatocarcinoma lymph node metastasis by upregulation of Annexin A7 and relevant mechanisms.

We unveiled the association of Annexin A7 with vascular endothelial growth factor-C (VEGF-C) and the effect of upregulation of Annexin A7 in Hca-F and Hca-P cells on inhibiting hepatocarcinoma (HCC) lymph node metastasis (LNM) in vitro and in vivo. A total of 200 inbred 615 mice were randomly divided into four equal groups inoculated with Hca-F, Hca-P, FAnxa7-upregulated, and PAnxa7-upregulated cells, respectively. The primary tumor, popliteal, inguinal, and iliac lymph nodes were prepared for immunohistochemical (IHC) staining, real-time quantitative polymerase chain reaction (qRT-PCR) analysis, Western blot, and hematoxylin-eosin (H&E) staining. There was over 50 % increase both in the number of FAnxa7-upregulated and PAnxa7-upregulated cells migrated through the filter compared to their controls (FAnxa7-control, Hca-F and PAnxa7-control, Hca-P). However, no significant differences were noted in invasion ability between them (all P > 0.05). Tumor lymph vessels were significantly reduced in FAnxa7-upregulated and PAnxa7-upregulated tumors when compared with Hca-F and Hca-P tumors (all P < 0.05). Blood vessel density did not differ significantly between FAnxa7-upregulated and PAnxa7-upregulated tumors and Hca-F and Hca-P tumors. Enzyme-linked immunosorbent assay (ELISA) for VEGF-C showed that upregulating Annexin A7 decreased VEGF-C secretion in FAnxa7-upregulated and PAnxa7-upregulated cells (P < 0.05). The IHC staining result showed that the level of serum Annexin A7 was found to be statistically higher in all experimental groups than that in the control group (P < 0.05). The present results indicated that alterations in serum Annexin A7 expression may be of prognostic relevance in HCC lymphatic metastasis.

Subchronic exposure to di-(2-ethylhexyl) phthalate (DEHP) elicits blood-brain barrier dysfunction and neuroinflammation in male C57BL/6J mice.

BACKGROUND: Exposure to di-(2-ethylhexyl) phthalate (DEHP) can cause neurotoxicity but the mechanism is not clear. Blood brain barrier (BBB) is one of the most important tissues to protect the brain. However, whether DEHP can disrupt the BBB or not remains unclear. The objective of this study is to investigate the potential effects of subchronic DEHP exposure on BBB integrity and discuss the role of BBB in DEHP inducible neurotoxicity with an emphasis on neuroinflammatory responses. Male adult C57BL/6J mice were orally administered with vehicle or 200 or 750 mg/kg/day DEHP for 90 days. Subchronic exposure to high-dose DEHP increased water intake but decreased body weight and brain weight. The concentrations of DEHP metabolites increased in serum from all DEHP-exposed groups while increased in brain only from the high-dose group. DEHP induced neurobehavioural alterations and damaged hippocampal neurons. DEHP increased BBB permeability by Evans blue (EB) extravasation and decreased tight junction proteins (ZO-1, occludin, and claudin-5) while presenting a neuroinflammatory feature characterized by the upregulated inflammatory mediators TNF-α and the NLRP3/caspase-1/IL-1ß inflammasome pathway. Our data provide new insights into neurotoxicity caused by subchronic DEHP exposure, which is probably involved in BBB dysfunction and neuroinflammatory responses.

MicroRNA-671-3p promotes proliferation and migration of glioma cells via targeting CKAP4.

BACKGROUND AND OBJECTIVE: Glioma is one of the most aggressive and malignant cancers originating from the human brain. Increasing evidence suggests that aberrant expression of microRNAs (miRNAs) frequently occurs in glioma and miRNAs are critical regulators of glioma. miR-671 has recently been revealed to be a novel miRNA that plays a vital role in human glioblastoma multiforme. However, the functional role and underlying mechanisms of miR-671-3p require further analysis. MATERIALS AND METHODS: Western blot and fluorescence quantitative PCR were used to assess the expression of cytoskeleton-associated protein 4 (CKAP4) and miR-671-3p, respectively. A Cell Counting Kit-8 (CCK-8) assay and a Boyden chamber assay were used to detect the proliferative and migratory abilities of glioma cells. A luciferase assay was used to determine the target gene of miR-671-3p. Apoptosis was analyzed by flow cytometry. RESULTS: Our results revealed that overexpression of miR-671-3p promoted cell proliferation and migration in vitro. Meanwhile, forced expression of miR-671-3p reduced apoptosis. In contrast, inhibition of miR-671-3p had the opposite effects. We also identified CKAP4 to be a direct target of miR-671-3p. The expression levels of CKAP4 were decreased in clinical samples and inversely correlated with miR-671-3p expression levels. Ectopic expression of CKAP4 reversed the promotive activity of miR-671-3p in the proliferation and migration and enhanced apoptosis. CONCLUSION: Our study demonstrates that miR-671-3p is a predominant positive regulator of glioma progression, thus providing new insights into the molecular mechanisms of glioma development. The findings suggest that the miR-6713p/CKAP4 axis may serve as a potential therapeutic target or biomarker in glioma.

[Preparation and identification of monoclonal antibodies against human pulmonary surfactant-associated protein A].

OBJECTIVE: To prepare monoclonal antibody (mAb) against human pulmonary surfactant-associated protein A (SP-A) and evaluate its specificities. METHODS: The hybridoma cell line secreting SP-A mAb was established to induce the production of SP-A ascites fluid in BALB/c mice immunized with SP-A. The ascites fluid was then collected and purified through (NH4)2SO4 salting-out procedure, and the titer and specificity of the purified monoclonal anti-SP-A antibodies were determined by Western blotting and indirect enzyme-linked immunosorbent assay, respectively. RESULTS: Three hybridoma cell lines capable of specific antibody secretion were established, among which 2B6 produced the antibody of the highest titer, with the hybridoma cell chromosome exceeding 100. The antibody titers in the ascitic fluid and cell supernatant fluid were 1: 50,000 and 1: 10,000 respectively, and Western blotting displayed a reaction band representing a relative molecular mass of 31,000, which was produced by the monoclonal antibody in reaction to purified SP-A. CONCLUSION: The antibodies of high purity and specificity against human SP-A have been successfully prepared.

Annexin A7 gene is an important factor in the lymphatic metastasis of tumors.

In the tumor malignancy progression, lymph node metastasis (LNM) is recognized as an important factor. In this study, RNA interference (RNAi) was employed to down-regulate ANXA7 gene in Hca-F cells, a hepatocarcinoma cell line with high LNM rate. There was no significant effect on cell proliferation ability, but cell division, motility, and invasion abilities were markedly inhibited. By contrast, up-regulating the expression of ANXA7 gene in Hca-P cells with lower LNM rate, cell migration ability was improved and the percentage of cells in S phase was significantly decreased in vitro. Here, we reported that the expression of Ech1, GSN and JNK1 genes, which were relevant to tumor lymphatic metastasis, had been inhibited due to down-regulation ANXA7 gene and promoted due to up-regulation ANXA7 gene by western blot analysis. These results indicated that ANXA7 is a critical factor in the development of lymphatic metastasis in hepatocarcinoma progression.

[Epidemiological and clinical analysis of Mycoplasma pneumoniae infection in children with acute respiratory tract infection].

OBJECTIVE: To summarize the epidemiology and clinical characteristics of Mycoplasma pneumoniae (MP) infection in children with acute respiratory tract infection (ARI) in Guangzhou. METHODS: MP was detected using an indirect immunofluorescent method in 2084 children with ARI. The relations between MP infection rate and the gender, age, season, site of infection and wheezing diseases were analyzed. RESULTS: A total of 433 children (20.8%) were positive for MP, including 222 boys (19.8%) and 211 girls (21.9%) without significant difference in the infection rate between the genders (P>0.05). In 0- to 3-year-old group, 106 children were positive for MP (15.0%), while in 3- to 5-year-old group and 5- to 14-year-old group, 163 (25.2%) and 164 (22.5%) were positive, respectively, showing a significant difference in the infection rate between the 3 groups (P<0.05). The MP infection rate was 18.0% in January to March, 25.1% in April to June, 17.7% in July to September, and 20.5% in October to December, showing significant differences between the periods (P<0.05). No significant difference was found in the infection rate between children with acute upper respiratory tract infection (URI) and those with lower respiratory tract infection (LRI) (P>0.05). Among the children with LRI, those having wheezing disease had significantly higher MP positivity rate than those without wheezing. CONCLUSION: MP is a common causative agent for ARI in children. MP infection is not related to gender and infection site, but to age and season. Children over 3 years old are vulnerable to MP infection. MP infection can be associated with wheezing in LRI.

A genomewide survey of homeobox genes and identification of novel structure of the Hox cluster in the silkworm, Bombyx mori.

Homeobox genes encode transcriptional factors that play crucial roles in a variety of developmental pathways from unicellular to multicellular eukaryotes. We have identified 102 homeobox genes in the typical insect of Lepidoptera, Bombyx mori, based on the newly assembled genome sequence with 9X coverage. These identified homeobox genes were categorized into nine classes including at least 74 families. The available ESTs and microarray data at present confirmed that more than half of them were expressed during silkworm developmental processes. Orthologs of pb, zen and ftz were newly identified in the Bombyx Hox cluster on chromosome 6. Interestingly, a special group of 12 tandemly duplicated homeobox genes was found located between Bmpb and Bmzen in the Bombyx Hox cluster, suggesting that Hox cluster might have experienced a lineage-specific expansion in the silkworm. A detailed analysis on genome data reveals that a split exists between Bmlab and Bmpb. Our data provide valuable information for future research on the development and evolution of silkworm.