A smartphone-enabled colorimetric platform based on enzyme cascade amplification strategy for detection of Staphylococcus aureus in milk.

Staphylococcus aureus is a pathogenic bacterium contaminating milk and dairy foods causing food poisoning and foodborne pathogens. In this work, a smartphone-enabled enzyme cascade-triggered colorimetric platform was constructed using a cascade bio-nanozyme formed by immobilized glucose oxidase (GOx) on Fe3O4@Ag for rapid detection of S. aureus. Benefiting from reasonable experimental design, a bio-nanozyme cascade-triggered reaction was achieved through H2O2 produced by GOx oxidation of glucose, followed by in situ catalysis of 3,3',5,5'-tetramethylbenzidine (TMB) by the inherent peroxidase-like activity of Fe3O4@Ag to produce color signals. Staphylococcus aureus detection could be performed through naked-eye observation and smartphone measurement, and the developed assay can achieve quantitative and qualitative detection of S. aureus. The on-site nanoplatform had satisfactory specificity and sensitivity with a low detection limit of 6.9 cfu·mL-1 in 50 min. Moreover, the nanoplatform has good practicality in the detection of S. aureus in milk samples. Therefore, the assay has potential application prospects in food safety inspection.

Culture of cerebrospinal fluid-contacting neurons from neonatal mouse spinal cord.

Cerebrospinal fluid-contacting neurons (CSF-cNs) act crucial role in chemosensory and mechanosensory function in spinal cord. Recently, CSF-cNs were found to be an immature neuron and may be involved in spinal cord injury recovery. But how to culture it and explore its function in vitro are not reported in previous research. Here, we first reported culture and identification of CSF-cNs in vitro. We first established a protocol for in vitro culture of CSF-cNs from the cervical spinal cord of mice within 24 h after birth. Polycystic kidney disease 2-like 1 (PKD2L1)+ cells were isolated by fluorescence-activated cell sorting and expressed the neuron marker ß-tubulin III and CSF-cNs marker GABA. Intriguingly, PKD2L1+ cells formed neurosphere and expressed neural stem cell markers Nestin, Sox2 and GFAP. Thus, our research provided culture and isolation of CSF-cNs and this facilitate the investigation the CSF-cNs function in vitro.

The serotonin transporter gene polymorphism is associated with the susceptibility and the pain severity in idiopathic trigeminal neuralgia patients.

BACKGROUND: To investigate the possible association between the serotonin transporter gene (5-HTTLPR) and rs 25531 polymorphism and the susceptibility and the pain severity in Trigeminal Neuralgia patients. METHODS: A total of 244 TN patients and 280 age and sex matched healthy volunteer were recruited. 5-HTTLPR and rs 25531 genotyping were performed. All patients received the carbamazepine treatment and the treatment response was evaluated at 6 months. RESULTS: The genotype distribution of 5-HTTLPR between TN patients and controls were significantly different. The TN Patients had a higher prevalence of short-short genotype than controls. The short-short genotype carriers are also significantly associated with higher pain severity and poorer carbamazepine treatment response compared to the long-long genotype carriers. In contrast, the rs 25531 polymorphism was not associated with the susceptibility to TN, neither with the pain severity and the treat response to carbamazepine. CONCLUSION: The 5-HTTLPR polymorphism is associated with the susceptibility to TN and pain severity of TN.

Degradation of Benzo[a]pyrene and 2,2',4,4'-Tebrabrominated Diphenyl Ether in Cultures Originated from an Agricultural Soil.

Benzo[a]pyrene (BaP) and 2,2',4,4'-tetrabrominated diphenyl ether (BDE-47) are common contaminants in the environment, posing a threat to the ecosystems and human health. Currently, information on the microbial metabolism of BaP and BDE-47 as well as the correlated bacteria is still limited. This research aimed to study the degradation of BaP and BDE-47 by enriched cultures originated from an agricultural soil in Tianjin (North China) and characterize the bacteria involved in the degradation. Two sets of experiments were set up with BaP and BDE-47 (2 mg/L) as the sole carbon source, respectively. The degradation of BaP and BDE-47 occurred at rate constants of 0.030 /d and 0.026 /d, respectively. For BaP, the degradation products included benzo[a]pyrene-9,10-dihydrodiol or its isomers, ben-zo(a)pyrene-7,8-dihydrodiol-9,10-epoxide, and cis-4 (8-hydroxypyrenyl-7)-2-oxo-3-butenoic acid. For BDE-47, the degradation products included 2,2',4-tribrominated diphenyl ether (BDE-17), 2,4-dibrominated diphenyl ether (BDE-7), and hydroxylated dibromodiphenyl ether. The bacterial community structures in the original soil, the BaP culture, and the BDE-47 culture were quite different. The richness and diversity of bacteria in the two cultures were much lower than that in the original soil, and the BaP culture had higher richness and diversity than the BDE-47 culture. In the BaP culture, multiple species such as Niabella (23.4%), Burkholderia-Caballeronia-Paraburkholderia (13.7%), Cupriavidus (8.3%), and Allorhizobi-um-Neorhizobium-Pararhizobium-Rhizobium (8.0%) were dominant. In the BDE-47 culture, an unassigned species in the Rhizobiaceae was dominant (82.3%). The results from this study provide a scientific basis for the risk assessment and bioremediation of BaP and/or BDE-47 in a contaminated environment.

A relatively dry mantle transition zone revealed by geomagnetic diurnal variations.

The distribution of water within the mantle transition zone (MTZ) has important implications for the material circulation and partial melting of the mantle. Although solubility of hydrogen is very high, leading to speculations that the MTZ plays a key role in the deep-Earth water cycle, the actual water content remains an open question. Electrical conductivity of mantle minerals is very sensitive to water content, so reliable estimates of this physical parameter in the MTZ would provide valuable constraints. Here, we use recently developed joint inversion of geomagnetic diurnal variation for realistic source structure and one-dimensional mantle conductivity profile. Synthetic tests show that the resulting profile is a reasonable proxy for the electrical conductivity distribution of continental mantle over depths where model resolution is best (200 to 600 kilometer), even in the presence of lateral heterogeneity. The inferred water concentration in the MTZ is 0.03 weight %, one to two orders of magnitude below the solubility of wadsleyite and ringwoodite.

Silencing of miR-150-5p Ameliorates Diabetic Nephropathy by Targeting SIRT1/p53/AMPK Pathway.

Diabetic nephropathy (DN) is a common complication of diabetes and an important cause of end-stage renal disease. Increasing evidence suggests that microRNAs (miRNAs) regulate the development of DN. In a preliminary study, high levels of miR-150-5p were detected in the serum and urine of patients with DN. Consequently, we investigated the effect and mechanism of action of miR-150-5p in DN in vitro and in vivo. Our results showed that inhibition of miR-150-5p reversed high glucose-induced podocyte injury and Streptozocin (STZ)-induced diabetic nephropathy in mice. Further analysis revealed that miR-150-5p targeted the 3' untranslated region (UTR) of sirtuin 1 (SIRT1), consequently decreasing SIRT1 levels in podocytes. Importantly, we found that the silencing of miR-150-5p promoted the interaction between SIRT1 and p53, causing the suppression of p53 acetylation in podocytes and kidney tissue. This resulted in the stimulation of AMP-activated protein kinase (AMPK)-dependent autophagy. In conclusion, our study demonstrated that the silencing of miR-150-5p played a reno-protective role in DN mice through targeting SIRT1.

circRNA circFAT1(e2) Elevates the Development of Non-Small-Cell Lung Cancer by Regulating miR-30e-5p and USP22.

BACKGROUND: As a newly discovered regulatory RNA, circular RNA (circRNA) has become a hot spot in many tumor pieces of research. In recent years, it has been discovered that circRNAs have multiple biological effects in different stages of cancer. However, the expression pattern and mechanism of circFAT1(e2) in non-small-cell lung cancer (NSCLC) are still unclear. METHODS: The expressions of circFAT1(e2) in NSCLC tissues and cell lines were studied. Functionally, CCK-8 and transwell experiments were performed in A549 and H1299. In addition, we also performed a dual-luciferase report analysis to clarify the mechanism of action of circFAT1(e2). RESULTS: circFAT1(e2) was significantly upregulated in NSCLC tissues and cell lines. circFAT1(e2) gene knockdown could significantly inhibit the proliferation, migration, and invasion of NSCLC cells. Loss of function testing found that circFAT1(e2) functioned as an oncogene in NSCLC cells. In addition, circFAT1(e2) acted as a ceRNA to spongy miR-30e-5p, which led to the increase in USP22 and promoted cell growth. CONCLUSIONS: The circFAT1(e2)-miR-30e-5p-USP22 axis is a crucial part of the progression of NSCLC. This study suggests that circFAT1(e2) may be an important potential of prognostic prediction and treatment targets for NSCLC patients.

The Neural Stem Cell Properties of PKD2L1+ Cerebrospinal Fluid-Contacting Neurons in vitro.

Cerebrospinal fluid-touching neurons (CSF-cNs) exist in the region surrounding the central canal of the spinal cord, which locate in the adult neurogenic niche. Previous research showed that CSF-cNs expressed the molecular markers of immature neural cells in vivo. Here, we explored the potential of CSF-cNs as neural stem cell in intro. We first found that PKD2L1+ CSF-cNs, isolating by FACS using the molecular marker PKD2L1 of CSF-cNs, expressed neural stem cells markers like Nestin, Sox2, and GFAP by immunofluorescence staining. PKD2L1+ CSF-cNs were able to form neurospheres and passaged in vitro. Immunofluorescence staining showed that the neurospheres forming by PKD2L1+ CSF-cNs also expressed neural stem cell markers Nestin, Sox2 and GFAP. The neurospheres expressed proliferation markers Ki67 and PCNA by immunofluorescence staining, indicating that the neurospheres forming by PKD2L1+ CSF-cNs were proliferative. The neurospheres, forming by CSF-cNs, had the ability of differentiation into neurons, astrocytes, and oligodendrocytes. Collectively, our data suggested that PKD2L1+ CSF-cNs have the properties of neural stem cells in vitro and may provide a promising approach for the repair of spinal cord injury.

3-Iodothyronamine Acting through an Anti-Apoptotic Mechanism Is Neuroprotective Against Spinal Cord Injury in Rats.

This study aims to show how 3-iodothyronamine (T1AM) protects against spinal cord injury (SCI) in rats. We randomly divided adult female Sprague-Dawley rats (N=54) into three equal groups: (1) untreated control (n=18) (2) T1AM (n=18) (3) T1AM+EPPTB (n=18). The clamp method was used to produce SCI at the T10 segment, and the following data were collected 3, 5, and 7 days after the injury plus treatment. The mean BBB scores of both the control and T1AM+EPPTB groups were 1.5±0.5, 3.5±0.5, and 4.5±0.5 on days 3, 5, and 7 after SCI, respectively, whereas those for the T1AM group were 3.3±0.5, 5.3±0.5, and 7.5±0.5, a significant difference from the first two groups mentioned on each day (all P values <0.05). Although HE staining indicated that all three groups displayed neuronal degeneration and necrosis, disorganized spinal cord tissue structure, proliferation of glial cells, and spinal cord porosis, the damage was less in the T1AM group than in the other two groups. The number of apoptotic cells gradually increased in all three groups. However, while the mean numbers of apoptotic cells in the control (9.8%±2.6%, 14.2%±5.9%, 57.2%±15.1%) and T1AM+EPPTB groups (9.1%±3.0%, 13.4%±6.3%, 57.4%±11.1%) on days 3, 5, and 7, respectively, were not significantly different from each other, those in the T1AM group (2.3%±1.4%, 7.6%±1.8%, 36.1%±9.9%) were significantly lower than those in both the other groups at each time point (all P values <0.05). Thus, T1AM is involved in the apoptosis pathway through stimulation of TAAR1. The T1AM-TAAR1 interaction decreased spinal cord neuron apoptosis, reduced secondary SCI, and promoted hind limb motor function recovery in rats with SCI.

The Study of Different Approaches of Parecoxib Sodium Pretreatment on the Behavior of Rats with Neuropathic Pain.

Our objective is to analyze and observe the different administration routes of parecoxib sodium pretreatment on the behavioral improvement of rats with neuropathic pain to provide the preclinical data of parecoxib sodium on neuropathic pain treatment. 30 SD rats were randomly divided into five groups, including model group, sham operation group, intrathecal injection group (IT group), intraperitoneal injection group (IP group), and perineural infiltration group (PI group). The rats in model group and three parecoxib sodium pretreatment groups received spinal nerve ligation (SNL). Heat pain test and 50 % paw mechanical withdrawal threshold test (50 % PMWT) were use to assess the responses after parecoxib sodium pretreatment. 50 % PMWT results of right foot in five groups had no statistical difference (P > 0.05); 50 % PMWT results of left and right feet in three parecoxib sodium pretreatment groups were obviously higher than SNL group at different time points, which was statistically different (P < 0.05); in comparison with three pretreatment groups, the data of left foot in IT group were obviously higher than PI group and IP group, and the comparison among three groups had significant difference (P < 0.05). However, the data of right foot had no significant difference among three groups (P > 0.05). Paw thermal withdrawal latency (PTWL) results of left and right feet in five groups had no significant difference before surgery (P > 0.05); after the establishment of neuropathic model, PTWL results in five groups were significantly decreased; however, PTWL results of left and right feet at 3 days after surgery in IT group were significantly higher than the two other pretreatment groups (P < 0.05); PTWL results of left and right feet at 7 and 14 days after surgery had no significant difference. Parecoxib sodium pretreatment can effectively improve the behaviors caused by neuropathic pain, and intrathecal injection is the most effective route of administration.