Activation of WNT7b autocrine eases metastasis of colorectal cancer via epithelial to mesenchymal transition and predicts poor prognosis.

BACKGROUND: Aberrant activation of the Wnt/ß-catenin signaling pathway is one of the most frequent abnormalities in human cancer, including colorectal cancer (CRC). Previous studies revealed pivotal functions of WNT family members in colorectal cancer, as well as their prognostic values. Nevertheless, the prognostic role and mechanisms underlying WNT7b in colorectal cancer development remains unclear. METHODS: In this study, WNT7b expression was measured by immunohistochemical staining of 100 cases of surgically resected human colorectal cancerous tissues as well as matched adjacent normal tissues constructed as tissue microarrays. In vitro studies, we attempted to substantiate the WNT7b expressional pattern previously found in immunohistochemistry staining. We used the colorectal cancer cell-line HCT116 and normal colorectal cell-line FHC for immunofluorescence staining and nuclear/cytoplasmic separated western blotting. We measured epithelial-mesenchymal transition (EMT) markers and migration capacity of HCT116 in the context of WNT7b knocked-down using short interfering RNA. Finally, clinical and prognostic values of WNT7b activation levels were examined. RESULTS: WNT7b was expressed in the nucleus in adjacent normal tissues. In CRC tissues, nuclear expression of WNT7b was similar; however, membrane and cytoplasmic expression was strikingly enhanced. Consistently, in vitro analysis confirmed the same expression pattern of WNT7b. Compared with FHC cells, HCT116 cells displayed higher levels of WNT7b membrane and cytoplasmic enrichment, as well as higher migration capacity with a sensitized EMT process. Either partial knockdown of WNT7b or blockade of the Wnt/ß-catenin signaling pathway reversed EMT process and inhibited the migration of HCT116 cells. Finally, elevated secretion levels of WNT7b were significantly associated with lymphatic and remote metastasis and predicted worse prognosis in the CRC cohort. CONCLUSION: In summary, we demonstrated that the activation of WNT7b autocrine probably contributes to CRC metastasis by triggering EMT process through the Wnt/ß-catenin signaling pathway. High levels of WNT7b autocrine secretion predicts poor outcome in patients with CRC. This molecule is a promising candidate for clinical CRC treatments.

Synthetic aperture focusing technique for photoacoustic endoscopy.

Photoacoustic endoscopy (PAE) is a promising tool for the detection of atherosclerotic plaque. In this work, we propose a novel design of a side-viewing PAE probe based on a synthetic aperture focusing technique (SAFT) to enable high transverse resolution over large depth of focus (DOF) along the radial direction. A point-like ultrasonic detector is used to ensure a wide detection angle and thus a large synthetic aperture for SAFT. We first perform numerical simulation to optimize the PAE probe design, which involves the placement of the point-like detector and the diameter of a reflection rod mirror. Then, experiments are conducted based on the optimized probe design. High transverse resolution of 115-190 µm over large DOF of 3.5 mm along the radial direction is experimentally obtained. The SAFT-based PAE holds promise for endoscopic imaging with a high transverse resolution for both the surface and deep regions of tissue.

Effects of different types of neonatal pain on somatosensory and cognitive development in male juvenile rats.

BACKGROUND: Premature infants are inevitably exposed to painful events, including repetitive procedures, inflammation, or mixed stimulation that may induce long-term behavioral outcomes. Here, we set up three neonatal painful models to investigate their long-term effect on somatosensation and cognition. METHODS: Three types of neonatal pain models in rat were set up. Rat pups were randomly assigned to four groups. The needling pain (NP) group received repetitive needle pricks on the paws from the day of birth (PD0) to postnatal day 7 (PD7) to mimic the diagnostic and therapeutic procedures. The inflammatory pain (IP) group received the injection of carrageenan into the left hindpaw at PD3 to induce IP in peripheral tissues. The mixed pain group received a combination of the NP and IP (NIP). The control (CON) group was untreated. We performed behavioral and biochemical testing of juvenile rats (PD21-PD26). RESULTS: The NIP group showed a longer hypersensitivity than the NP group, when given a secondary inflammatory stimulation. NP led to insensitivity to anxiety-causing stimuli and impairment of fear memory both aggravated by NIP. NP reduced the expression of synapse-related molecules (GluN1/PSD95/GFAP) in the medial prefrontal cortex, and NIP exacerbated this decrease. The corticosterone secretion in the NIP group increased after the behavioral task, compared with those in other three groups. CONCLUSION: A combination of NP with inflammation occurring in the neonatal period might aggravate the adverse effects of each on somatosensory and cognitive development of rats, the mechanism of which might be associated with the increase of corticosterone secretion and the dysregulation of synaptic molecules.

Enriched environment rescues neonatal pain induced cognitive deficits and the impaired hippocampal synaptic plasticity later in life.

Although extensive and untreated pain that occurs during a critical developmental window may impair cognition later in life, environmental interventions early in life might promote cognition. However, the underlying mechanism is poorly understood. Our current study utilized a rat model of "repetitive needle pricks" from the day of birth (P0) to postnatal day 7 (P7) to mimic the painful experience of preterm neonates in the neonatal intensive care unit. Enriched environment (EE) during development period (from P15 to P70) was implemented as a nonpharmacological intervention approach. Electrophysiological recording, behavioral tests, and biochemical analysis were performed after the end of EE (between P71 and P80). The results showed neonatal repetitive pain resulted in a reduction in mechanical withdrawal thresholds by the von Frey test in P70 (p < .001). Furthermore, neonatal repetitive pain impaired spatial learning and memory (p < .05) and even led to dysfunction in fear memory (p < .01). In contrast, EE rescued neonatal pain-induced cognitive deficits and normalized hippocampal long-term potentiation in rats exposed to neonatal pain (p << .05). The beneficial effect of EE might be the improvements in hippocampal synaptic plasticity via upregulating neurotrophic factors and N-methyl-d-aspartate (NMDA) receptors in the hippocampus. Our findings provide evidence that early environmental intervention might be a safe strategy to overcome neurodevelopmental abnormalities in preterm infants who experienced multiple procedural painful events during the early critical period.

Repetitive Pain in Neonatal Male Rats Impairs Hippocampus-Dependent Fear Memory Later in Life.

Preterm infants in neonatal intensive care units are inevitably subjected to numerous painful procedures. However, little is known about the consequences of early pain experience on fear memory formation later in life. We hypothesized that exposure to repetitive pain in early life triggered hippocampal synaptic plasticity and resulted in memory deficiency in prepubertal and adult rats. From the day of birth (P0) to postnatal day 7 (P7), neonatal male rat pups were randomly assigned to either needle pricks or tactile touches repetitively every 6 h. Trace fear conditioning was performed on rats on P24-P26 and P87-P89. On P24 and P87, rats were sacrificed for molecular and electrophysiological studies. On P24-26 and P87-89, rats that experienced neonatal needle treatment showed a significant reduction in freezing time in the contextual fear conditioning (P < 0.05) and trace fear conditioning tests (P < 0.05). Moreover, repetitive neonatal procedural pain caused a significant decrease in the magnitude of hippocampal long-term potentiation induced by high-frequency stimulation. Furthermore, rats that experienced neonatal needle treatment demonstrated sustained downregulation of NR1, NR2A, NR2B, and GluR1 expression in the hippocampus. Therefore, neonatal pain is related to deficits in hippocampus-related fear memory later in life and might be caused by impairments in hippocampal synaptic plasticity.

[Spectral analysis of some brass coins excavsted from Ezhou of Hubei province].

XRD and XRF were used to identify several brass coins of Qing dynasty collected in the Ezhou Museum and excavated from Ezhou of Hubei province. The reality of the coins contains 36.53%-37.75% of Zn, 54.12%-59.04% of Cu and 3.51%-7.56% of Pb, and the ration of the alloy is steady and scientific, indicating that the technic of the alloy of brass was quite perfect in the mid to late of Qing dynasty. Zn3Cu2 (OH)6 (CO3)2 was found in the corrosion for the first time, and CuO, ZnO, Fe2O3 and CuCl were found too. The high content of Cl-, around the local condition (including the polluted environment), may be the main reason for those brass coins to be eroded seriously. These findings provide some reference for collecting and protecting coins.

Neonatal repetitive pain in rats leads to impaired spatial learning and dysregulated hypothalamic-pituitary-adrenal axis function in later life.

Preterm birth is a major health issue. As part of their life-saving care, most preterm infants require hospitalization and are inevitably exposed to repetitive skin-breaking procedures. The long-term effects of neonatal repetitive pain on cognitive and emotional behaviors involving hypothalamic-pituitary-adrenal (HPA) axis function in young and adult rats are unknown. From P8 to P85, mechanical hypersensitivity of the bilateral hindpaws was observed in the Needle group (P < 0.001). Compared with the Tactile group, the Needle group took longer to find the platform on P30 than on P29 (P = 0.03), with a decreased number of original platform site crossings during the probe trial of the Morris water maze test (P = 0.026). Moreover, the Needle group spent more time and took longer distances in the central area than the Tactile group in the Open-field test, both in prepubertal and adult rats (P < 0.05). The HPA axis function in the Needle group differed from the Tactile group (P < 0.05), with decreased stress responsiveness in prepuberty and puberty (P < 0.05) and increased stress responsiveness in adulthood (P < 0.05). This study indicates that repetitive pain that occurs during a critical period may cause severe consequences, with behavioral and neuroendocrine disturbances developing through prepuberty to adult life.