GABABR1 in DRN mediated GABA to regulate 5-HT expression in multiple brain regions in male rats with high and low aggressive behavior.

The identity of the mechanism that controls aggressive behavior in rodents is unclear. Serotonin (5-HT) and GABA are associated with aggressive behavior in rodents. However, the regulatory relationship between these chemicals in the different brain regions of rats has not been fully defined. This study aimed to clarify the role of GABABR1 in DRN-mediated GABA to regulate 5-HT expression in multiple brain regions in male rats with high and low aggressive behavior. Rat models of highly and less aggressive behavior were established through social isolation plus resident intruder. On this basis, GABA content in the DRN and 5-HT contents in the PFC, hypothalamus, hippocampus and DRN were detected using ELISA. Co-expression of 5-HT and GB1 in the DRN was detected by immunofluorescence and immunoelectron microscopy at the tissue and subcellular levels, respectively. GB1-specific agonist baclofen and GB1-specific inhibitor CGP35348 were injected into the DRN by stereotaxic injection. Changes in 5-HT levels in the PFC, hypothalamus and hippocampus were detected afterward. After modeling, rats with highly aggressive behavior exhibited higher aggressive behavior scores, shorter latencies of aggression, and higher total distances in the open field test than rats with less aggressive behavior. The contents of 5-HT in the PFC, hypothalamus and hippocampus of rats with high and low aggressive behavior (no difference between the two groups) were significantly decreased, but the change in GABA content in the DRN was the opposite. GB1 granules could be found on synaptic membranes containing 5-HT granules, which indicated that 5-HT neurons in the DRN co-expressed with GB1, which also occurred in double immunofluorescence results. At the same time, we found that the expression of GB1 in the DRN of rats with high and low aggressive behavior was significantly increased, and the expression of GB1 in the DRN of rats with low aggressive behavior was significantly higher than that in rats with high aggressive behavior. Nevertheless, the expression of 5-HT in DRN was opposite in these two groups. After microinjection of baclofen into the DRN, the 5-HT contents in the PFC, hypothalamus and hippocampus of rats in each group decreased significantly. In contrast, the 5-HT contents in the PFC, hypothalamus and hippocampus of rats in each group increased significantly after injection with CGP35348. The significant increase in GABA in the DRN combined with the significant increase in GB1 in the DRN further mediated the synaptic inhibition effect, which reduced the 5-HT level of 5-HT neurons in the DRN, resulting in a significant decrease in 5-HT levels in the PFC, hypothalamus and hippocampus. Therefore, GB1-mediated GABA regulation of 5-HT levels in the PFC, hypothalamus and hippocampus is one of the mechanisms of highly and less aggressive behavior originating in the DRN. The increased GB1 level in the DRN of LA-behavior rats exhibited a greater degree of change than in the HA-group rats, which indicated that differently decreased 5-HT levels in the DRN may be the internal mechanisms of high and low aggression behaviors.

Delivery room resuscitation and short-term outcomes of extremely preterm and extremely low birth weight infants: a multicenter survey in North China.

BACKGROUND: Delivery room resuscitation assists preterm infants, especially extremely preterm infants (EPI) and extremely low birth weight infants (ELBWI), in breathing support, while it potentially exerts a negative impact on the lungs and outcomes of preterm infants. This study aimed to assess delivery room resuscitation and discharge outcomes of EPI and ELBWI in China. METHODS: The clinical data of EPI (gestational age [GA] <28 weeks) and ELBWI (birth weight [BW] <1000 g), admitted within 72 h of birth in 33 neonatal intensive care units from five provinces and cities in North China between 2017 and 2018, were analyzed. The primary outcomes were delivery room resuscitation and risk factors for delivery room intubation (DRI). The secondary outcomes were survival rates, incidence of bronchopulmonary dysplasia (BPD), and risk factors for BPD. RESULTS: A cohort of 952 preterm infants were enrolled. The incidence of DRI, chest compressions, and administration of epinephrine was 55.9% (532/952), 12.5% (119/952), and 7.0% (67/952), respectively. Multivariate analysis revealed that the risk factors for DRI were GA <28 weeks (odds ratio [OR], 3.147; 95% confidence interval [CI], 2.082-4.755), BW <1000 g (OR, 2.240; 95% CI, 1.606-3.125), and antepartum infection (OR, 1.429; 95% CI, 1.044-1.956). The survival rate was 65.9% (627/952) and was dependent on GA. The rate of BPD was 29.3% (181/627). Multivariate analysis showed that the risk factors for BPD were male (OR, 1.603; 95% CI, 1.061-2.424), DRI (OR, 2.094; 95% CI, 1.328-3.303), respiratory distress syndrome exposed to ≥2 doses of pulmonary surfactants (PS; OR, 2.700; 95% CI, 1.679-4.343), and mechanical ventilation ≥7 days (OR, 4.358; 95% CI, 2.777-6.837). However, a larger BW (OR, 0.998; 95% CI, 0.996-0.999), antenatal steroid (OR, 0.577; 95% CI, 0.379-0.880), and PS use in the delivery room (OR, 0.273; 95% CI, 0.160-0.467) were preventive factors for BPD (all P < 0.05). CONCLUSION: Improving delivery room resuscitation and management of respiratory complications are imperative during early management of the health of EPI and ELBWI.

Biological effects of radiation on cancer cells.

With the development of radiotherapeutic oncology, computer technology and medical imaging technology, radiation therapy has made great progress. Research on the impact and the specific mechanism of radiation on tumors has become a central topic in cancer therapy. According to the traditional view, radiation can directly affect the structure of the DNA double helix, which in turn activates DNA damage sensors to induce apoptosis, necrosis, and aging or affects normal mitosis events and ultimately rewires various biological characteristics of neoplasm cells. In addition, irradiation damages subcellular structures, such as the cytoplasmic membrane, endoplasmic reticulum, ribosome, mitochondria, and lysosome of cancer cells to regulate various biological activities of tumor cells. Recent studies have shown that radiation can also change the tumor cell phenotype, immunogenicity and microenvironment, thereby globally altering the biological behavior of cancer cells. In this review, we focus on the effects of therapeutic radiation on the biological features of tumor cells to provide a theoretical basis for combinational therapy and inaugurate a new era in oncology.

Effects of Oxalic Acid on Arsenic Uptake and the Physiological Responses of Hydrilla verticillata Exposed to Different Forms of Arsenic.

A hydroponic experiment was conducted to investigate the effects of oxalic acid (OA) on arsenic (As) uptake and the physiological responses of Hydrilla verticillata exposed to 3 mg L-1 of As in different forms. Plant As(III) uptake was significantly increased by 200-2000 µg L-1 OA. However, an increase of As(V) uptake was only shown with 1000 µg L-1 OA, and no significant difference was observed with dimethylarsinate treatment. Peroxidase and catalase activities, and the contents of photosynthetic pigments, soluble sugar and proline, were significantly increased by 1000 µg L-1 OA during As(III) treatment. Superoxide dismutase and proline were also increased significantly by 1000 µg L-1 OA when plants were exposed to As(V). In DMA treatment, proline was significantly increased by 500 µg L-1 OA. Therefore, As-induced oxidative stress is relieved by OA, but it depends on OA concentration and the form of As. Our results may be useful for the phytoremediation of waste water containing As and OA.

Bifunctional fused polypeptide inhibits the growth and metastasis of breast cancer.

Breast cancer is the most common cancer and the leading cause of cancer-related death among women worldwide, with urgent need to develop new therapeutics. Targeted therapy is a promising strategy for breast cancer therapy. Stromal-derived factor-1/CXC chemokine receptor 4 (CXCR4) has been implicated in the metastasis of breast cancer, which renders it to be therapeutic target. This study aimed to evaluate the anticancer effect of fused TAT- DV1-BH3 polypeptide, an antagonist of CXCR4, and investigate the underlying mechanism for the cancer cell-killing effect in the treatment of breast cancer in vitro and in vivo. This results in a potent inhibitory effect of fused TAT-DV1-BH3 polypeptide on tumor growth and metastasis in nude mice bearing established MDA-MB-231 tumors. Fused TAT-DV1-BH3 polypeptide inhibited the proliferation of MDA-MB-231 and MCF-7 cells but did not affect that of HEK-293 cells. The fused TAT-DV1-BH3 polypeptide colocalized with mitochondria and exhibited a proapoptotic effect through the regulation of caspase-9 and -3. Furthermore, the fused TAT-DV1-BH3 polypeptide suppressed the migration and invasion of the highly metastatic breast cancer cell line MDA-MB-231 in a concentration-dependent manner. Notably, the DV1-mediated inhibition of the stromal-derived factor-1/CXCR4 pathway contributed to the antimetastasis effect, evident from the reduction in the level of phosphoinositide 3 kinase and matrix metalloproteinase 9 in MDA-MB-231 cells. Collectively, these results indicate that the apoptosis-inducing effect and migration- and invasion-suppressing effect explain the tumor regression and metastasis inhibition in vivo, with the involvement of caspase- and CXCR4-mediated signaling pathway. The data suggest that the fused TAT-DV1-BH3 polypeptide is a promising agent for the treatment of breast cancer, and more studies are warranted to fully elucidate the therapeutic targets and molecular mechanism.

[Common pathogens and clinical characteristics of neonatal pneumonia].

OBJECTIVE: To study common pathogens and their antibiotic susceptibility as well as clinical characteristics of neonatal pneumonia. METHODS: A retrospective study on neonatal pneumonia was performed. The study investigated antibiotic susceptibility of four common pathogens (339 strains) that caused neonatal pneumonia. Clinical characteristics of the newborns with pneumonia were analyzed. Of the 339 strains, 185 were isolated from bronchial secretions, 72 from blood samples, and 82 with positive results of both samples. RESULTS: Four hundred and seventy-four neonates with pneumonia presented positive results of bacterial culture. the most common pathogens Staphylococcus aureus (21.9%), Escherichia coli (19.2%), Klebsiella pneumoniae (19.0%) and Enterobacter cloacae (11.4%). The birth weight of newborns infected with Staphylococcus aureus was generally normal, and the time of hospital admission was later (after 24 hours of life). In contrast, the newborns with gram-negative bacterial infection, especially Klebsiella pneumoniae infection, had lower birth weights and early time of hospital admission (within 24 hours of life). Nearly more than 50% gram-negative bacteria were resistant to second, third and forth generation cephaloporins. CONCLUSIONS: Gram-negative bacteria are predominant pathogens of neonatal pneumonia. Neonatal pneumonia caused by gram-negative bacteria is common in newborns with low birth weight and its onset time is relatively earlier. Gram-negative bacteria that cause neonatal pneumonia are highly resistant to cephaloporins.

Template synthesized molecularly imprinted polymer nanotube membranes for chemical separations.

In this report, we describe the synthesis of a molecularly imprinted polymer (MIP) nanotube membrane, using a porous anodic alumina oxide (AAO) membrane by surface-initiated atom transfer radical polymerization (ATRP). The use of a MIP nanotube membrane in chemical separations gives the advantage of high affinity and selectivity. Furthermore, because the molecular imprinting technique can be applied to different kinds of target molecules, ranging from small organic molecules to peptides and proteins, such MIP nanotube membranes will considerably broaden the application of nanotube membranes in chemical separations and sensors. This report also shows that the ATRP route is an efficient procedure for the preparation of molecularly imprinted polymers. Furthermore, the ATRP route works well in its formation of MIP nanotubes within a porous AAO membrane. The controllable nature of ATRP allows the growth of a MIP nanotube with uniform pores and adjustable thickness. Thus, using the same route, it is possible to tailor the synthesis of MIP nanotube membranes with either thicker MIP nanotubes for capacity improvement or thinner nanotubes for efficiency improvement.