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1.
Nanomaterials (Basel) ; 12(5)2022 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-35269363

RESUMEN

BN is the currently required segregant for perpendicular FePt media. We found that BN can be diffused from the MgTiOBN intermediate layer during a high temperature process. The FePtCAg film sputtered on MgTiOBN layers illustrates higher perpendicular magnetocrystalline anisotropy (Ku) (1.43 × 107 erg/cm3) and coercivity (normal to film surface) (17 kOe) at 350 K compared to BN/FePtCAg/MgTiON film. From the microstructure, the FePtCAg film shows the granular structure on the MgTiOBN intermediate layer, but parts of the irregular FePt grains are agglomerated and partially separated in the matrix, with grains size being, on average, 26.7 nm. Cross-sectional imaging showed that the FePt grains have a truncated pyramid shape with a lower wetting angle, which is influenced by the surface energy of MgTiOBN. BN segregation at FePt grains or boundaries is still not clear. Using the electron energy loss spectrum (EELS), we found that part of the BN atoms were clearly observed in the FePt lattice and iron-boride oxide was indexed in the x-ray photoelectron spectroscopy (XPS) spectra. To determine the effects of BN segregant (from capping layer or intermediate layer) on the magnetic switching behavior of FePtCAg film, the intrinsic-(ΔHint = 6.17 kOe, 6.54 kOe) and extrinsic- (ΔHext = 0.80 kOe, 0.39 kOe) switching field distribution (SFD) were measured by plotting saturated major- and unsaturated minor- hysteresis loops to evaluate the crystal orientation and microstructure (grains volume and distribution) for BN/FePtCAg/MgTiON and FePtCAg/MgTiOBN films, respectively. The main contribution of intrinsic SFD is the c-axis misalignment for the BN/FePt/MgTiON sample; however, the dispersed magnetic anisotropy has a higher input to intrinsic SFD for FePtCAg/MgTiOBN/CrRu film.

2.
Medicine (Baltimore) ; 99(40): e22431, 2020 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-33019422

RESUMEN

BACKGROUND: In this analysis, we aimed to systematically compare the procedural and post-operative complications (POC) associated with laparoscopic versus open abdominal surgery for right-sided colonic cancer resection. METHODS: We searched MEDLINE, http://www.ClinicalTrials.gov, EMBASE, Web of Science, Cochrane Central, and Google scholar for English studies comparing the POC in patients who underwent laparoscopic versus open surgery (OS) for right colonic cancer. Data were assessed by the Cochrane-based RevMan 5.4 software (The Cochrane Community, London, UK). Mean difference (MD) with 95% confidence intervals (CIs) were used to represent the results for continuous variables, whereas risk ratios (RR) with 95% CIs were used for dichotomous data. RESULTS: Twenty-six studies involving a total number of 3410 participants with right colonic carcinoma were included in this analysis. One thousand five hundred and fifteen participants were assigned to undergo invasive laparoscopic surgery whereas 1895 participants were assigned to the open abdominal surgery. Our results showed that the open resection was associated with a shorter length of surgery (MD: 48.63, 95% CI: 30.15-67.12; P = .00001) whereas laparoscopic intervention was associated with a shorter hospital stay [MD (-3.09), 95% CI [-5.82 to (-0.37)]; P = .03]. In addition, POC such as anastomotic leak (RR: 0.96, 95% CI: 0.60-1.55; P = .88), abdominal abscess (RR: 1.13, 95% CI: 0.52-2.49; P = .75), pulmonary embolism (RR: 0.40, 95% CI: 0.09-1.69; P = .21) and deep vein thrombosis (RR: 0.94, 95% CI: 0.39-2.28; P = .89) were not significantly different. Paralytic ileus (RR: 0.87, 95% CI: 0.67-1.11; P = .26), intra-abdominal infection (RR: 0.82, 95% CI: 0.15-4.48; P = .82), pulmonary complications (RR: 0.83, 95% CI: 0.57-1.20; P = .32), cardiac complications (RR: 0.73, 95% CI: 0.42-1.27; P = .27) and urological complications (RR: 0.83, 95% CI: 0.52-1.33; P = .44) were also similarly manifested. Our analysis also showed 30-day re-admission and re-operation, and mortality to be similar between laparoscopic versus OS for right colonic carcinoma resection. However, surgical wound infection (RR: 0.65, 95% CI: 0.50-0.86; P = .002) was significantly higher with the OS. CONCLUSIONS: In conclusion, laparoscopic surgery was almost comparable to OS in terms of post-operative outcomes for right-sided colonic cancer resection and was not associated with higher unwanted outcomes. Therefore, laparoscopic intervention should be considered as safe as the open abdominal surgery for right-sided colonic cancer resection, with a decreased hospital stay.


Asunto(s)
Colectomía/métodos , Neoplasias del Colon/cirugía , Laparoscopía/métodos , Complicaciones Posoperatorias/epidemiología , Anciano , Colectomía/efectos adversos , Femenino , Humanos , Laparoscopía/efectos adversos , Tiempo de Internación/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Tempo Operativo
3.
Neuron ; 107(5): 909-923.e6, 2020 09 09.
Artículo en Inglés | MEDLINE | ID: mdl-32649865

RESUMEN

The parabrachial nucleus (PBN) is one of the major targets of spinal projection neurons and plays important roles in pain. However, the architecture of the spinoparabrachial pathway underlying its functional role in nociceptive information processing remains elusive. Here, we report that the PBN directly relays nociceptive signals from the spinal cord to the intralaminar thalamic nuclei (ILN). We demonstrate that the spinal cord connects with the PBN in a bilateral manner and that the ipsilateral spinoparabrachial pathway is critical for nocifensive behavior. We identify Tacr1-expressing neurons as the major neuronal subtype in the PBN that receives direct spinal input and show that these neurons are critical for processing nociceptive information. Furthermore, PBN neurons receiving spinal input form functional monosynaptic excitatory connections with neurons in the ILN, but not the amygdala. Together, our results delineate the neural circuit underlying nocifensive behavior, providing crucial insight into the circuit mechanism underlying nociceptive information processing.


Asunto(s)
Vías Aferentes , Lateralidad Funcional/fisiología , Núcleos Talámicos Intralaminares , Nocicepción/fisiología , Núcleos Parabraquiales , Vías Aferentes/citología , Vías Aferentes/fisiología , Amígdala del Cerebelo , Animales , Núcleos Talámicos Intralaminares/citología , Núcleos Talámicos Intralaminares/fisiología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Neuronas/citología , Neuronas/fisiología , Núcleos Parabraquiales/citología , Núcleos Parabraquiales/fisiología , Médula Espinal/citología , Médula Espinal/fisiología
4.
J Hazard Mater ; 398: 122936, 2020 11 05.
Artículo en Inglés | MEDLINE | ID: mdl-32512450

RESUMEN

Lead pipe has been banned in the drinking water distribution system in most countries since 1980s. Although water authorities around the world have attempted to replace all remaining lead pipes in service, pipe replacement was often hindered by high cost and lack of access to private premises. Hence, partial replacement has become a common scenario where portions of lead pipes remain in the system. When the lead pipe is connected to two other different metallic materials at both ends, two different galvanic couples can form simultaneously in this three-metal system. The release of lead resulting from galvanic corrosion in such three-metal systems consisting of lead (Pb), copper (Cu) and stainless steel (SS) with three different configurations, namely Cu-SS-Pb, SS-Cu-Pb and Cu-Pb-SS was investigated in this study. The results showed that when the materials are arranged in order of reduction potential as in SS-Cu-Pb configuration, lead release was the highest. A more fluent electron transport across the system was proposed based on the direction and magnitude of galvanic currents measured at each galvanic couple.


Asunto(s)
Agua Potable , Contaminantes Químicos del Agua , Cobre/análisis , Corrosión , Plomo , Acero Inoxidable , Contaminantes Químicos del Agua/análisis , Abastecimiento de Agua
5.
Neurobiol Dis ; 130: 104486, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31150793

RESUMEN

Accumulated genetic evidences indicate that the contactin associated protein-like (CNTNAP) family is implicated in autism spectrum disorders (ASD). In this study, we identified genetic mutations in the CNTNAP3 gene from Chinese Han ASD cohorts and Simons Simplex Collections. We found that CNTNAP3 interacted with synaptic adhesion proteins Neuroligin1 and Neuroligin2, as well as scaffolding proteins PSD95 and Gephyrin. Significantly, we found that CNTNAP3 played an opposite role in controlling the development of excitatory and inhibitory synapses in vitro and in vivo, in which ASD mutants exhibited loss-of-function effects. In this study, we showed that the male Cntnap3-null mice exhibited deficits in social interaction, spatial learning and prominent repetitive behaviors. These evidences elucidate the pivotal role of CNTNAP3 in synapse development and social behaviors, providing mechanistic insights into ASD.


Asunto(s)
Trastorno del Espectro Autista/genética , Predisposición Genética a la Enfermedad/genética , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Neurogénesis/genética , Conducta Social , Animales , Conducta Animal , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Mutación , Sinapsis
6.
Oncol Res ; 27(2): 139-146, 2019 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-29471888

RESUMEN

Inhibition of tumor metastasis is one of the most important purposes in colorectal cancer (CRC) treatment. This study aimed to explore the effects of liquiritigenin, a flavonoid extracted from the roots of Glycyrrhiza uralensis Fisch, on HCT116 cell proliferation, invasion, and epithelial-to-mesenchymal transition (EMT). We found that liquiritigenin significantly inhibited HCT116 cell proliferation, invasion, and the EMT process, but had no influence on cell apoptosis. Moreover, liquiritigenin remarkably reduced the expression of runt-related transcription factor 2 (Runx2) in HCT116 cells. Overexpression of Runx2 obviously reversed the liquiritigenin-induced invasion and EMT inhibition. Furthermore, liquiritigenin inactivated the phosphoinositide 3-kinase/protein kinase B (PI3K/AKT) pathway in HCT116 cells. Upregulation of Runx2 reversed the liquiritigenin-induced PI3K/AKT pathway inactivation. In conclusion, our research verified that liquiritigenin exerted significant inhibitory effects on CRC invasion and EMT process by downregulating the expression of Runx2 and inactivating the PI3K/AKT signaling pathway. Liquiritigenin could be an effective therapeutic and preventative medicine for CRC treatment.


Asunto(s)
Neoplasias Colorrectales/tratamiento farmacológico , Subunidad alfa 1 del Factor de Unión al Sitio Principal/antagonistas & inhibidores , Transición Epitelial-Mesenquimal/efectos de los fármacos , Flavanonas/farmacología , Proliferación Celular/efectos de los fármacos , Neoplasias Colorrectales/patología , Subunidad alfa 1 del Factor de Unión al Sitio Principal/fisiología , Células HCT116 , Humanos , Invasividad Neoplásica , Fosfatidilinositol 3-Quinasas/fisiología , Inhibidores de las Quinasa Fosfoinosítidos-3 , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-akt/fisiología , Transducción de Señal/efectos de los fármacos
7.
J Neurosci ; 39(3): 456-471, 2019 01 16.
Artículo en Inglés | MEDLINE | ID: mdl-30459220

RESUMEN

AGRP (agouti-related neuropeptide) expressing inhibitory neurons sense caloric needs of an animal to coordinate homeostatic feeding. Recent evidence suggests that AGRP neurons also suppress competing actions and motivations to mediate adaptive behavioral selection during starvation. Here, in adult mice of both sexes we show that AGRP neurons form inhibitory synapses onto ∼30% neurons in the medial preoptic area (mPOA), a region critical for maternal care. Remarkably, optogenetically stimulating AGRP neurons decreases maternal nest-building while minimally affecting pup retrieval, partly recapitulating suppression of maternal behaviors during food restriction. In parallel, optogenetically stimulating AGRP projections to the mPOA or to the paraventricular nucleus of hypothalamus but not to the LHA (lateral hypothalamus area) similarly decreases maternal nest-building. Chemogenetic inhibition of mPOA neurons that express Vgat (vesicular GABA transporter), the population targeted by AGRP terminals, also decreases maternal nest-building. In comparison, chemogenetic inhibition of neurons in the LHA that express vesicular glutamate transporter 2, another hypothalamic neuronal population critical for feeding and innate drives, is ineffective. Importantly, nest-building during low temperature thermal challenge is not affected by optogenetic stimulation of AGRP→mPOA projections. Finally, via optogenetic activation and inhibition we show that distinctive subsets of mPOA Vgat+ neurons likely underlie pup retrieval and maternal nest-building. Together, these results show that AGRP neurons can modulate maternal nest-building, in part through direct projections to the mPOA. This study corroborates other recent discoveries and underscores the broad functions that AGRP neurons play in antagonizing rivalry motivations to modulate behavioral outputs during hunger.SIGNIFICANCE STATEMENT In order for animals to initiate ethologically appropriate behaviors, they must typically decide between behavioral repertoires driven by multiple and often conflicting internal states. How neural pathways underlying individual behaviors interact to coherently modulate behavioral outputs, in particular to achieve a proper balance between behaviors that serve immediate individual needs versus those that benefit the propagation of the species, remains poorly understood. Here, by investigating projections from a neuronal population known to drive hunger behaviors to a brain region critical for maternal care, we show that activation of AGRP→mPOA projections in females dramatically inhibits maternal nest-building while leaving mostly intact pup retrieval behavior. Our findings shed new light on neural organization of behaviors and neural mechanisms that coordinate behavioral selection.


Asunto(s)
Proteína Relacionada con Agouti/fisiología , Conducta Materna/fisiología , Red Nerviosa/fisiología , Comportamiento de Nidificación/fisiología , Neuronas/fisiología , Área Preóptica/fisiología , Proteína Relacionada con Agouti/genética , Animales , Frío , Femenino , Privación de Alimentos , Área Hipotalámica Lateral/fisiología , Masculino , Ratones , Ratones Transgénicos , Optogenética , Núcleo Hipotalámico Paraventricular/fisiología , Proteínas del Transporte Vesicular de Aminoácidos Inhibidores/metabolismo
8.
Neuron ; 101(1): 45-59.e9, 2019 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-30554781

RESUMEN

Uncontrollable itch-scratching cycles lead to serious skin damage in patients with chronic itch. However, the neural mechanism promoting the itch-scratching cycle remains elusive. Here, we report that tachykinin 1 (Tac1)-expressing glutamatergic neurons in the lateral and ventrolateral periaqueductal gray (l/vlPAG) facilitate the itch-scratching cycle. We found that l/vlPAG neurons exhibited scratching-behavior-related neural activity and that itch-evoked scratching behavior was impaired after suppressing the activity of l/vlPAG neurons. Furthermore, we showed that the activity of Tac1-expressing glutamatergic neurons in the l/vlPAG was elevated during itch-induced scratching behavior and that ablating or suppressing the activity of these neurons decreased itch-induced scratching behavior. Importantly, activation of Tac1-expressing neurons induced robust spontaneous scratching and grooming behaviors. The scratching behavior evoked by Tac1-expressing neuron activation was suppressed by ablation of spinal neurons expressing gastrin-releasing peptide receptor (GRPR), the key relay neurons for itch. These results suggest that Tac1-expressing neurons in the l/vlPAG promote itch-scratching cycles.


Asunto(s)
Neuroquinina A/biosíntesis , Neuronas/metabolismo , Sustancia Gris Periacueductal/metabolismo , Prurito/metabolismo , Tractos Piramidales/metabolismo , Receptores de Neuroquinina-1/biosíntesis , Animales , Expresión Génica , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Neuroquinina A/genética , Neuronas/química , Sustancia Gris Periacueductal/química , Prurito/patología , Tractos Piramidales/química , Distribución Aleatoria , Receptores de Neuroquinina-1/genética , Taquicininas/biosíntesis , Taquicininas/genética
9.
Nat Commun ; 9(1): 279, 2018 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-29348568

RESUMEN

The medial preoptic area (mPOA) differs between males and females in nearly all species examined to date, including humans. Here, using fiber photometry recordings of Ca2+ transients in freely behaving mice, we show ramping activities in the mPOA that precede and correlate with sexually dimorphic display of male-typical mounting and female-typical pup retrieval. Strikingly, optogenetic stimulation of the mPOA elicits similar display of mounting and pup retrieval in both males and females. Furthermore, by means of recording, ablation, optogenetic activation, and inhibition, we show mPOA neurons expressing estrogen receptor alpha (Esr1) are essential for the sexually biased display of these behaviors. Together, these results underscore the shared layout of the brain that can mediate sex-specific behaviors in both male and female mice and provide an important functional frame to decode neural mechanisms governing sexually dimorphic behaviors in the future.


Asunto(s)
Encéfalo/fisiología , Neuronas/fisiología , Área Preóptica/fisiología , Conducta Sexual Animal , Animales , Encéfalo/metabolismo , Receptor alfa de Estrógeno/metabolismo , Femenino , Humanos , Masculino , Ratones Endogámicos C57BL , Ratones Transgénicos , Neuronas/metabolismo , Optogenética/métodos , Área Preóptica/metabolismo , Factores Sexuales
10.
Proc Natl Acad Sci U S A ; 114(8): 2042-2047, 2017 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-28053227

RESUMEN

The homeostatic control of body temperature is essential for survival in mammals and is known to be regulated in part by temperature-sensitive neurons in the hypothalamus. However, the specific neural pathways and corresponding neural populations have not been fully elucidated. To identify these pathways, we used cFos staining to identify neurons that are activated by a thermal challenge and found induced expression in subsets of neurons within the ventral part of the lateral preoptic nucleus (vLPO) and the dorsal part of the dorsomedial hypothalamus (DMD). Activation of GABAergic neurons in the vLPO using optogenetics reduced body temperature, along with a decrease in physical activity. Optogenetic inhibition of these neurons resulted in fever-level hyperthermia. These GABAergic neurons project from the vLPO to the DMD and optogenetic stimulation of the nerve terminals in the DMD also reduced body temperature and activity. Electrophysiological recording revealed that the vLPO GABAergic neurons suppressed neural activity in DMD neurons, and fiber photometry of calcium transients revealed that DMD neurons were activated by cold. Accordingly, activation of DMD neurons using designer receptors exclusively activated by designer drugs (DREADDs) or optogenetics increased body temperature with a strong increase in energy expenditure and activity. Finally, optogenetic inhibition of DMD neurons triggered hypothermia, similar to stimulation of the GABAergic neurons in the vLPO. Thus, vLPO GABAergic neurons suppressed the thermogenic effect of DMD neurons. In aggregate, our data identify vLPO→DMD neural pathways that reduce core temperature in response to a thermal challenge, and we show that outputs from the DMD can induce activity-induced thermogenesis.


Asunto(s)
Núcleo Hipotalámico Dorsomedial/fisiología , Neuronas GABAérgicas/fisiología , Vías Nerviosas/fisiología , Área Preóptica/fisiología , Termogénesis/fisiología , Animales , Calcio/metabolismo , Frío , Fenómenos Electrofisiológicos , Calor , Hipotermia/fisiopatología , Inmunohistoquímica , Ratones , Fotometría , Proteínas Proto-Oncogénicas c-fos/metabolismo
11.
J Biol Chem ; 288(15): 10361-73, 2013 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-23430746

RESUMEN

Pro-opiomelanocortin (POMC) is a common precursor of melanocortin-related peptides in the pituitary and primarily regulated by corticotropin- releasing factor (CRF). Our results show that miR-375 is highly expressed in the mouse pituitary gland and located specifically in the intermediate lobe of pituitary. The functional studies show that the forced inhibition of endogenous miR-375 in AtT-20 mouse pituitary tumor cells and in the intermediate lobe of the pituitary gland significantly increases POMC expression, whereas miR-375 overexpression down-regulates POMC expression and ACTH secretion stimulated by CRF. This function of miR-375 is accomplished by its binding to the 3'-UTR of mitogen-activated protein kinase kinase kinase-8. Our results here have demonstrated that miR-375 acts as a negative regulating molecule mediating the signaling pathway of CRF and affecting POMC expression by targeting mitogen-activated protein kinase kinase kinase-8, which subsequently down-regulates ERK1/2 phosphorylation and nerve growth factor-induced clone B (NGFI-B) transcription activity. Taken together, our results show that miR-375 is a novel negative regulator of POMC expression and related hormone secretion.


Asunto(s)
Hormona Liberadora de Corticotropina/metabolismo , Regulación de la Expresión Génica/fisiología , Sistema de Señalización de MAP Quinasas/fisiología , MicroARNs/metabolismo , Proteína Quinasa 8 Activada por Mitógenos/metabolismo , Hipófisis/metabolismo , Proopiomelanocortina/biosíntesis , Animales , Línea Celular Tumoral , Hormona Liberadora de Corticotropina/genética , Femenino , Masculino , Ratones , MicroARNs/genética , Proteína Quinasa 3 Activada por Mitógenos/genética , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Proteína Quinasa 8 Activada por Mitógenos/genética , Miembro 1 del Grupo A de la Subfamilia 4 de Receptores Nucleares/genética , Miembro 1 del Grupo A de la Subfamilia 4 de Receptores Nucleares/metabolismo , Fosforilación/fisiología , Neoplasias Hipofisarias/genética , Neoplasias Hipofisarias/metabolismo , Proopiomelanocortina/genética
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