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1.
Nat Commun ; 12(1): 7170, 2021 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-34887395

RESUMEN

Two-dimensional crystals with angstrom-scale pores are widely considered as candidates for a next generation of molecular separation technologies aiming to provide extreme, exponentially large selectivity combined with high flow rates. No such pores have been demonstrated experimentally. Here we study gas transport through individual graphene pores created by low intensity exposure to low kV electrons. Helium and hydrogen permeate easily through these pores whereas larger species such as xenon and methane are practically blocked. Permeating gases experience activation barriers that increase quadratically with molecules' kinetic diameter, and the effective diameter of the created pores is estimated as ∼2 angstroms, about one missing carbon ring. Our work reveals stringent conditions for achieving the long sought-after exponential selectivity using porous two-dimensional membranes and suggests limits on their possible performance.

2.
Rev Med Liege ; 76(11): 773-775, 2021 Nov.
Artículo en Francés | MEDLINE | ID: mdl-34738748

RESUMEN

Postherpetic neuralgia is the most feared complication of herpes zoster (HZ). The incidence increases with age. Nevertheless, around 5 % of HZ patients will experience a motor deficiency known as segmental zoster paresis (SZP) according to the affected dermatome. Abdominal pseudohernia is an exceptional clinical presentation of SZP, involving the T6-L1 dermatomas. The recognition of this rare complication of HZ prevents unnecessary explorations and interventions. There is no specific treatment but in general the evolution is favorable and spontaneous healing is observed within several months.


La névralgie post-zostérienne est la complication la plus redoutée du zona, et son incidence augmente avec l'âge. Néanmoins, environ 5 % des patients peuvent également présenter une atteinte motrice appelée parésie segmentaire zostérienne (PSZ) et dont la clinique dépend du dermatome affecté. La pseudohernie abdominale est une forme exceptionnelle de PSZ, dépendant des dermatomes T6-L1. Reconnaître cette complication rare permet d'éviter des explorations et des interventions inutiles. Il n'y a pas de traitement spécifique et, en règle générale, l'évolution est spontanément favorable en quelques mois.


Asunto(s)
Pared Abdominal , Herpes Zóster , Herpes Zóster/complicaciones , Herpes Zóster/diagnóstico , Humanos , Paresia
3.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 56(4): 335-341, 2021 Apr 09.
Artículo en Chino | MEDLINE | ID: mdl-33832034

RESUMEN

Objective: To study the effect of various concentrations of Enterococcus faecalis (Ef) supernatants on human periodontal ligament cell (hPDLC) and the inflammatory response of hPDLC under static pressure. Methods: The method of methyl thiazolyl tetrazolium (MTT) was used to detect the effect of various concentrations of Ef supernatants on the proliferation of hPDLCs and the flow cytometry was used to detect the expression of Toll-like receptor 2 (TLR-2) on the surface of hPDLC after 24-hour-stimulation of Ef supernatant. Furthermore, the hPDLCs were divided into non inducing group without Ef supernatant and inducing group with 5% Ef supernatant, and hPDLCs in each group were loaded with 0, 49 and 196 Pa static pressures respectively. The expressions of tumor necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß) mRNA and protein were detected by reverse transcription-PCR (RT-PCR) and enzyme linked immunosorbent assay (ELISA) after 24 hours. Results: MTT results showed that the supernatant of Ef with concentration≥5% could significantly inhibit the proliferation activity of hPDLCs at 48 hours of cell culture (P<0.05). Flow cytometry showed that the positive cell rates of TLR-2 increased with increasing volume fractions of the Ef supernatants. The values were (2.12±0.07)%, (2.41±0.32)%, (2.65±0.27)%, (4.76±0.46)%, (9.91±0.92)% and (12.01±1.35)%, respectively. The differences were statistically significant when the concentrations≥5% (P<0.05). There were no significant differences in the expressions of IL-1ß and TNF-α mRNA between the non inducing group and the control group under the pressure of 49 Pa (P>0.05). However, there were significant differences in the expressions of IL-1ß and TNF-α mRNA between the non inducing group and the control group under the pressure of 196 Pa (P<0.05), while the expressions of IL-1ß and TNF-α in the inducing group were significantly lower than that in the control group under the pressures of 49 and 196 Pa (P<0.05). Compared with the control group, the mRNA expression was significantly increased (P<0.05). The result of ELISA was consistent with that of PCR. Conclusions: High concentration of Ef supernatant could inhibit the proliferation of hPDLC. Ef supernatant might promote the expression of TLR-2 on the surface of hPDLC. Excessive mechanical pressure induced the inflammatory response of hPDLC. The presence of inflammatory mediators could lead to the intolerance of hPDLC to pressures and small pressure could aggravate the inflammatory response.


Asunto(s)
Enterococcus faecalis , Ligamento Periodontal , Humanos , Interleucina-1beta , Lipopolisacáridos , ARN Mensajero , Factor de Necrosis Tumoral alfa
4.
Nature ; 588(7837): 250-253, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33299189

RESUMEN

Capillary condensation of water is ubiquitous in nature and technology. It routinely occurs in granular and porous media, can strongly alter such properties as adhesion, lubrication, friction and corrosion, and is important in many processes used by microelectronics, pharmaceutical, food and other industries1-4. The century-old Kelvin equation5 is frequently used to describe condensation phenomena and has been shown to hold well for liquid menisci with diameters as small as several nanometres1-4,6-14. For even smaller capillaries that are involved in condensation under ambient humidity and so of particular practical interest, the Kelvin equation is expected to break down because the required confinement becomes comparable to the size of water molecules1-22. Here we use van der Waals assembly of two-dimensional crystals to create atomic-scale capillaries and study condensation within them. Our smallest capillaries are less than four ångströms in height and can accommodate just a monolayer of water. Surprisingly, even at this scale, we find that the macroscopic Kelvin equation using the characteristics of bulk water describes the condensation transition accurately in strongly hydrophilic (mica) capillaries and remains qualitatively valid for weakly hydrophilic (graphite) ones. We show that this agreement is fortuitous and can be attributed to elastic deformation of capillary walls23-25, which suppresses the giant oscillatory behaviour expected from the commensurability between the atomic-scale capillaries and water molecules20,21. Our work provides a basis for an improved understanding of capillary effects at the smallest scale possible, which is important in many realistic situations.

5.
Rev Med Liege ; 75(5-6): 445-451, 2020 May.
Artículo en Francés | MEDLINE | ID: mdl-32496695

RESUMEN

Over the last decade, Physical and Rehabilitation Medicine (PRM) is a medical specialty that has evolved considerably in the various fields that concern it : from the management of low back pain and lumbosciatalgia or osteoporosis in a multidisciplinary manner, through the use of new technologies in neuro-locomotor rehabilitation and robotisation in amputee patients for example, the development of regenerative medicine and prevention in sports traumatology and, finally, the progress of electrophysiology techniques for the diagnosis of small-fibre neuropathies. These various advances will be discussed in this article.


Au cours de la dernière décennie, la Médecine Physique et Réadaptation (MPR) est une spécialité médicale qui a fortement évolué dans les différents domaines qui la concernent : de la prise en charge des lombalgies et lombosciatalgies ou encore de l'ostéoporose de manière pluridisciplinaire, en passant par l'utilisation des nouvelles technologies en rééducation neuro-locomotrice et de la robotisation en rééducation, chez les patients amputés par exemple, le développement de la médecine à vocation régénérative et la prévention en traumatologie du sport et, enfin, les progrès des techniques d'électrophysiologie pour le diagnostic des neuropathies à petites fibres. Ces différentes avancées seront abordées dans cet article.


Asunto(s)
Dolor de la Región Lumbar , Osteoporosis , Medicina Física y Rehabilitación , Competencia Clínica , Humanos , Dolor de la Región Lumbar/terapia , Osteoporosis/terapia , Medicina Física y Rehabilitación/tendencias
6.
Eur Rev Med Pharmacol Sci ; 24(5): 2683-2691, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32196619

RESUMEN

OBJECTIVE: Previous studies have shown that nucleus pulposus (NP) cell death plays an extremely important role in the progress of intervertebral disc degeneration (IVDD). This research aimed to investigate the protective effect of the MLKL inhibitor necrosulfonamide (NSA) on human NP cells. PATIENTS AND METHODS: We collected human NP tissues from the patients undergoing disc herniation operations and isolated NP cell from the samples. IL-1ß (10 ng/ml) was used to establish a NP cells degenerated model. We analyzed the expression of caspase 3, caspase 8, RIPK1, RIPK 3, and MLKL in different degree of degenerate disc tissues. Cell viability was analyzed by the Cell Counting Kit-8 (CCK-8) assay. The expression levels of collagen Ⅱ, ß-galactosidase (ß-gal), caspase 3, caspase 8, RIPK1, RIPK 3, and MLKL, several inflammatory and anti-oxidant enzymes of different NP cell treat groups were detected by Western blotting, immunofluorescence staining, or RT-PCR. Flow cytometry was used to measure the ROS level and cell apoptosis. RESULTS: The data showed that expression of caspase 3, caspase 8, RIPK1, RIPK 3, and MLKL markedly increased in severely degenerated disc tissues. IL-1ß promoted the cell death of NP cells, while NSA could reverse the effects of IL-1ß. We found that NAS increased the antioxidant SOD1, SOD2, CAT, and GPX3 expression and suppressed oxidative stress in the disc. Moreover, MMP3, MMP10, IL-6, and TNF-α were significantly suppressed by the NSA. CONCLUSIONS: These results suggest that NSA prevented NP degradation via inhibiting apoptosis and necroptosis of NP cells. Besides, the protective function of antagonizing cell death may owe to the inflammation and oxidative stress suppression.


Asunto(s)
Acrilamidas/farmacología , Apoptosis/efectos de los fármacos , Degeneración del Disco Intervertebral/prevención & control , Necroptosis/efectos de los fármacos , Núcleo Pulposo/efectos de los fármacos , Sulfonamidas/farmacología , Adulto , Anciano , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Femenino , Humanos , Degeneración del Disco Intervertebral/diagnóstico , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Coloración y Etiquetado
7.
Nature ; 579(7798): 229-232, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32161387

RESUMEN

Despite being only one-atom thick, defect-free graphene is considered to be completely impermeable to all gases and liquids1-10. This conclusion is based on theory3-8 and supported by experiments1,9,10 that could not detect gas permeation through micrometre-size membranes within a detection limit of 105 to 106 atoms per second. Here, using small monocrystalline containers tightly sealed with graphene, we show that defect-free graphene is impermeable with an accuracy of eight to nine orders of magnitude higher than in the previous experiments. We are capable of discerning (but did not observe) permeation of just a few helium atoms per hour, and this detection limit is also valid for all other gases tested (neon, nitrogen, oxygen, argon, krypton and xenon), except for hydrogen. Hydrogen shows noticeable permeation, even though its molecule is larger than helium and should experience a higher energy barrier. This puzzling observation is attributed to a two-stage process that involves dissociation of molecular hydrogen at catalytically active graphene ripples, followed by adsorbed atoms flipping to the other side of the graphene sheet with a relatively low activation energy of about 1.0 electronvolt, a value close to that previously reported for proton transport11,12. Our work provides a key reference for the impermeability of two-dimensional materials and is important from a fundamental perspective and for their potential applications.

8.
Clin Neurophysiol ; 131(2): 372-376, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31865138

RESUMEN

OBJECTIVES: To evaluate the sensitivity and specificity of the latency difference (DLat) between ulnar and median nerves of the arm after stimulation at the wrist; one of the easiest techniques proposed for recognizing ulnar neuropathy at the elbow (UNE). As latency difference is not a standardized technique, we set up a multicenter study to recruit large numbers of normal subjects and patients with UNE or generalized neuropathy. METHODS: Six centers participated in the study with data obtained from three groups of participants, controls (CTRLs), patients with UNE and patients with generalized neuropathy (GNP). We first verified the anatomical superposition of the ulnar and median nerves in cadaver examination. The optimal recording site for these two nerves was found to be 10 cm above the medial epicondyle. We then standardized the position of the arm with full extension of the elbow and stimulated first the median and then the ulnar nerves at the wrist. CTRLs were examined on both arms at two consecutive visits. RESULTS: We recorded 32 idiopathic UNE cases, 44 GNP patients and 62 controls. We demonstrated that a DLat cut-off value of 0.69 ms brings a sensitivity of 0.86 and specificity of 0.89 to discriminate CTRLs from UNE. We also validated that intra-examiner reproducibility was good. CONCLUSION: We report a lower normal value for DLat than reported in several non-standardized studies and CTRL and UNE groups have clearly separated DLat values. SIGNIFICANCE: Due to its high sensitivity, our standardized technique could be used as a first-line diagnostic tool when UNE is suspected.


Asunto(s)
Electrodiagnóstico/métodos , Nervio Mediano/fisiopatología , Conducción Nerviosa , Nervio Cubital/fisiopatología , Neuropatías Cubitales/fisiopatología , Adulto , Anciano , Codo/fisiopatología , Electrodiagnóstico/normas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tiempo de Reacción , Sensibilidad y Especificidad , Neuropatías Cubitales/diagnóstico , Muñeca/fisiopatología
9.
J Biol Regul Homeost Agents ; 33(5): 1337-1345, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31637903

RESUMEN

The effects of miR-145 (microRNA 145) on M. pneumoniae (MP)-infected MRC-5 (Medical Research Council cell strain 5) cell TGF-ß/Smad (transforming growth factor beta/Smad) fibrosis pathway were explored through constructing MP-infected MRC-5 cell models. In addition, the qPCR (quantitative real-time polymerase chain reaction) and Western blot were applied to detect the mRNA and protein expressions of miR-145, TGF-ß1 (transforming growth factor beta 1), Smad3, Smad4, MMP2 (matrix metalloproteinase 2), FN1 (fibronectin 1), ELN (elastin) and COLI α1 (collagen type I alpha 1) signaling molecules in TGF-ß/Smad fibrosis pathway. The results showed that the expression of miR-145 in MRC-5 cells was significantly increased after MP infection. In addition, miR-145 inhibited the fibrosis promoting TGF-ß/Smad pathway by targeting Smad3, a key factor in the TGF-ß/Smad pathway. It can be concluded that, in the process of MP infection, the expression of miR-145 is stimulated to negatively regulate the fibrosis-promoting pathway of TGF-ß/Smad.


Asunto(s)
Fibroblastos/patología , MicroARNs/metabolismo , Mycoplasma pneumoniae , Proteínas Smad/metabolismo , Línea Celular , Fibroblastos/microbiología , Fibrosis , Humanos , Metaloproteinasa 2 de la Matriz/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo
10.
Zhonghua Gan Zang Bing Za Zhi ; 27(8): 604-609, 2019 Aug 20.
Artículo en Chino | MEDLINE | ID: mdl-31594077

RESUMEN

Objective: To investigate the curative effect of antiviral therapy and related factors influencing the curative affect in children with immune-tolerant phase chronic hepatitis B. Methods: From May 2014 to April 2015, 46 children with chronic hepatitis B, aged 1 to 16 years with immune-tolerant phase were enrolled as the treatment group. All cases in the treated group either received interferon alpha (3-5 MIU/m(2), once daily) in lamivudine combination (if HBV DNA decreased < 2 log(10)) or repeatedly received interferon-alpha alone (if HBV DNA decreased >2 log(10)) for 12 weeks. Interferon was discontinued at 72 weeks and followed-up period was continued with lamivudine for 24 weeks. At the same time, data of 23 cases of untreated children with immune-tolerant phase chronic hepatitis B were collected as the control group. The treatment group and the control group were divided into two age groups: 1-7 years old and 7-15 years old. Data measurements were compared using t-test, analysis of variance and single factor analysis methods, and the count data were analyzed by χ (2) test. Multiple logistic regression analysis was used to analyze the effects of different factors on response. Results: (1) There were 22 cases aged 1-7 years in the treatment group (47.8%) and 12 cases aged 1-7 years in the control group (52.2%). The cases of mother-to-child transmission (MTCT) in treatment and control group were 34 (73.9%) and 17 (73.9%), while children with normal baseline ALT in the treatment and control group were 18 (39.1%) and 10 (43.5%). (2) At the end of follow-up, 15 cases in the treatment group (32.6%) had HBeAg serological conversion. Among them, nine (19.6%) cases had HBsAg clearance or HB-Ag seroconversion with anti-HBs, and one (2.2%) case had HBsAg clearance, but both HBeAg and anti-HBe were positive. In the control group, one case had HBV DNA lower than the lower limit of detection level, and one case had HBeAg seroconversion without HBsAg clearance. (3) At the end of follow-up, the seroconversion rates of HBeAg in patients aged 1 to 7 years and patients aged 7 to 15 years were 45.5% and 20.8%, respectively (P = 0.078) and the clearance rates of HBsAg were 36.4% and 8.3% (P = 0.023). The serum conversion rates of normal and abnormal baseline alanine aminotransferase levels were 5.6% and 50.0% (P = 0.005), and the clearance rates of HBsAg were 5.6% and 32.1% (P = 0.077), respectively. There was no statistically significant difference in gender, mother-to-child transmission, HBV DNA genotyping and baseline HBsAg level in antiviral efficacy among children (P > 0.05). (4) HBsAg and HBeAg clearance occurred in 100% of patients at the end of follow-up who had HBsAg < 3 000 IU/ml at 24 weeks of treatment. (5) Multivariate logistic regression analysis showed that serum HBeAg conversion rate had relation with non-MTCT transmission and abnormal baseline alanine aminotransferase. Furthermore, HBsAg clearance rate was associated with the age of children. Conclusion: Sequential combination of interferon and lamivudine with a prolonged course can improve the HBV DNA negative conversion rate, HBeAg seroconversion rate, HBsAg loss rate and mild ALT abnormalities at baseline in children under the age of 7 years with immune-tolerant phase chronic hepatitis B.


Asunto(s)
Antivirales/uso terapéutico , Hepatitis B Crónica/tratamiento farmacológico , Interferones/uso terapéutico , Lamivudine/uso terapéutico , Adolescente , Niño , Preescolar , ADN Viral/sangre , Quimioterapia Combinada , Antígenos de Superficie de la Hepatitis B/sangre , Antígenos e de la Hepatitis B/sangre , Humanos , Lactante , Transmisión Vertical de Enfermedad Infecciosa , Resultado del Tratamiento
11.
Science ; 363(6423): 145-148, 2019 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-30630924

RESUMEN

It has long been an aspirational goal to create artificial structures that allow fast permeation of water but reject even the smallest hydrated ions, replicating the feat achieved by nature in protein channels (e.g., aquaporins). Despite recent progress in creating nanoscale pores and capillaries, these structures still remain distinctly larger than protein channels. We report capillaries made by effectively extracting one atomic plane from bulk crystals, which leaves a two-dimensional slit of a few angstroms in height. Water moves through these capillaries with little resistance, whereas no permeation could be detected even for such small ions as Na+ and Cl- Only protons (H+) can diffuse through monolayer water inside the capillaries. These observations improve our understanding of molecular transport at the atomic scale.

12.
Zhonghua Er Ke Za Zhi ; 57(1): 40-45, 2019 Jan 02.
Artículo en Chino | MEDLINE | ID: mdl-30630230

RESUMEN

Objective: To review and analyze the clinical and pathological data of children with autoimmune hepatitis (AIH). Methods: Medical records of 46 patients hospitalized in Pediatric Liver Diseases Treatment and Research Center, Fifth Medical Center, General Hospital of People's Liberation Army(PLA) from April 2012 to April 2018 were extracted. Medical data included type of AIH, clinical manifestations, biochemical parameters, liver biopsy results, and outcomes of treatment were analyzed retrospectively. Among 46 children, 19 were males and 27 were females. The age of onset was 10.1(1.4-18.0) years old. Chi-Square test, Rank sum test or t test were used for inter-group comparison. Results: There were 32 (70%)AIH-I cases and 14 (30%)AIH-Ⅱ cases (χ(2)=12.565, P=0.000). Among the 46 patients, there were 5 modes of onest: 17 cases (37%) had acute viral hepatitis-like presentation, 2 cases (4%) had fulminant hepatic failure, 9 cases (20%) had insidious onset, 5 cases (11%) showed cirrhosis and portal hypertension, and 13 cases (28%) were incidentally found to be due to elevated hepatic aminotransferases. Comorbidities including primary sclerotic cholangitis (n=3), primary biliary cholangitis (n=1), systemic lupus erythematosus (n=1) and inflammatory bowel disease (n=2), were all seen in AIH-Ⅰ cases. The elevated biochemical parameters of these patients were as follows: alanine aminotransferase (n=46), aspartate transminase (n=46), total bilirubin (n=35) γ-glutamyl transpeptadase (n=39), γ-globulin (n=32) and IgG (n=33). The γ-globulin and IgG levels were significantly higher in AIH-Ⅰ patients than those with AIH-Ⅱ((32±9)% vs. (23±8)%, t=3.217, P=0.002,(27±10) vs. (18±8)g/L, t=3.193, P=0.003, respectively). Thirty-nine patients received liver biopsy, among whom 22 (56%) with inflammation grade (G)≥3, 26(67%) with fibrosis stage (S) ≥3, and 7 with hepatic cirrhosis (S4) according to pathological analysis. Typical histopathological changes of AIH included: 36 cases of interfacial hepatitis (92%), 23 cases of lymphocyte/plasma cell infiltration (59%), 3 cases of rosette (8%). Forty patients received prednisolone monotherapy or combined with azathioprine after diagnosis. Complete remission was seen in 29 (72%) patients, partial remission in 10 (25%) patients and no response in 1 (3%) patient. Among complete remission patients, 15 (52%) had relapse in the process of prednisolone reduction. Repeated liver biopsy performed in 8 patients after treatment showed that hepatic inflammation and fibrosis were both improved in 6 patients, only inflammation was alleviated without fibrosis improvement in 1 patient, and neither inflammation nor fibrosis was improved in 1 case. The length of follow-up was 3.3 (0.3-10.5) years, and none of the 39 prednisolone-responded cases discontinued treatment successfully. Adverse effect of long-term prednisolone therapy included bilateral cataract (n=6), spinal fracture accompanied with delayed bone age development (n=1). Conclusions: AIH-Ⅰ is more common than AIH-Ⅱ in children, with diverse clinical characteristics. Most cases have progressive liver inflammation and fibrosis when diagnosed. Prednisolone monotherapy or combined with azathioprine could achieve both biochemical and pathological improvement, but relapse is inevitable during drug tapering, hence long-term treatment is essential.


Asunto(s)
Glucocorticoides , Hepatitis Autoinmune , Prednisolona , Adolescente , Niño , Femenino , Glucocorticoides/uso terapéutico , Hepatitis Autoinmune/complicaciones , Hepatitis Autoinmune/tratamiento farmacológico , Hepatitis Autoinmune/patología , Humanos , Cirrosis Hepática , Masculino , Prednisolona/uso terapéutico , Estudios Retrospectivos , Resultado del Tratamiento
14.
Nature ; 558(7710): 420-424, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29925968

RESUMEN

Gas permeation through nanoscale pores is ubiquitous in nature and has an important role in many technologies1,2. Because the pore size is typically smaller than the mean free path of gas molecules, the flow of the gas molecules is conventionally described by Knudsen theory, which assumes diffuse reflection (random-angle scattering) at confining walls3-7. This assumption holds surprisingly well in experiments, with only a few cases of partially specular (mirror-like) reflection known5,8-11. Here we report gas transport through ångström-scale channels with atomically flat walls12,13 and show that surface scattering can be either diffuse or specular, depending on the fine details of the atomic landscape of the surface, and that quantum effects contribute to the specularity at room temperature. The channels, made from graphene or boron nitride, allow helium gas flow that is orders of magnitude faster than expected from theory. This is explained by specular surface scattering, which leads to ballistic transport and frictionless gas flow. Similar channels, but with molybdenum disulfide walls, exhibit much slower permeation that remains well described by Knudsen diffusion. We attribute the difference to the larger atomic corrugations at molybdenum disulfide surfaces, which are similar in height to the size of the atoms being transported and their de Broglie wavelength. The importance of this matter-wave contribution is corroborated by the observation of a reversed isotope effect, whereby the mass flow of hydrogen is notably higher than that of deuterium, in contrast to the relation expected for classical flows. Our results provide insights into the atomistic details of molecular permeation, which previously could be accessed only in simulations10,14, and demonstrate the possibility of studying gas transport under controlled confinement comparable in size to the quantum-mechanical size of atoms.

16.
Neurogastroenterol Motil ; 30(7): e13307, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29392784

RESUMEN

BACKGROUND: Acupuncture is used to treat chronic functional constipation (CFC) in China, despite limited evidence. We aim to assess the effectiveness and safety of acupuncture in managing CFC. METHODS: A multicenter randomized controlled trial was performed involving 684 patients with CFC; the patients were randomly allocated to receive He acupuncture (n = 172), Shu-mu acupuncture (n = 171), He-shu-mu acupuncture (n = 171), or oral administration of mosapride (n = 170). Sixteen sessions of acupuncture were given in the treatment duration of 4 weeks. The primary outcome was the change in spontaneous bowel movements (SBMs) at week 4 (at the end of treatment) compared to baseline. The secondary outcomes included stool consistency (Bristol scale), the degree of straining during defecation, and adverse events. KEY RESULTS: The SBMs increased in all the four groups at week 4, and the magnitude of increase was equivalent in the four groups (He acupuncture, 2.7 [95% CI, 2.3-3.1]; Shu-mu acupuncture, 2.7 [95% CI, 2.3-3.0]; He-shu-mu acupuncture, 2.2 [95% CI, 1.9-2.5]; and mosapride, 2.4 [95% CI, 2.0-2.9]; P = .226). However, the change in SBMs at week 8 was significantly smaller in mosapride group (1.4 [95% CI, 1.0-1.8]) than the three acupuncture groups (2.4 [95% CI, 2.1-2.7], 2.3 [95% CI, 1.9-2.7], 2.1 [95% CI, 1.7-2.5] in He, Shu-mu, and He-shu-mu group, respectively, P = .005). CONCLUSIONS & INTERFERENCES: The three acupuncture treatments were as effective as mosapride in improving stool frequency and stool consistency in CFC, but the magnitude of the treatment effect is unknown due to the lack of sham acupuncture control.


Asunto(s)
Terapia por Acupuntura/métodos , Estreñimiento/fisiopatología , Estreñimiento/terapia , Adulto , Benzamidas/uso terapéutico , Enfermedad Crónica , Estreñimiento/diagnóstico , Femenino , Estudios de Seguimiento , Fármacos Gastrointestinales/uso terapéutico , Humanos , Masculino , Persona de Mediana Edad , Morfolinas/uso terapéutico , Resultado del Tratamiento
17.
Mol Psychiatry ; 23(4): 883-891, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29180673

RESUMEN

Extracellular ATP is a widespread cell-to-cell signaling molecule in the brain, where it functions as a neuromodulator by activating glia and neurons. Although ATP exerts multiple effects on synaptic plasticity and neuro-glia interactions, as well as in mood disorders, the source and regulation of ATP release remain to be elaborated. Here, we define Calhm2 as an ATP-releasing channel protein based on in vitro and in vivo models. Conventional knockout and conditional astrocyte knockout of Calhm2 both lead to significantly reduced ATP concentrations, loss of hippocampal spine number, neural dysfunction and depression-like behaviors in mice, which can be significantly rescued by ATP replenishment. Our findings identify Calhm2 as a critical ATP-releasing channel that modulates neural activity and as a potential risk factor of depression.


Asunto(s)
Adenosina Trifosfato/metabolismo , Astrocitos/metabolismo , Depresión/metabolismo , Animales , Encéfalo/metabolismo , Canales de Calcio/metabolismo , Trastorno Depresivo/metabolismo , Modelos Animales de Enfermedad , Hipocampo/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Neuroglía/metabolismo , Plasticidad Neuronal/fisiología , Neuronas/metabolismo , Factores de Riesgo , Transducción de Señal
18.
Acta Psychiatr Scand ; 137(2): 98-108, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29280500

RESUMEN

OBJECTIVE: PANSS-8 and PANSS-6 are derived from the 30-item Positive and Negative Syndrome Scale (PANSS-30). We investigate whether PANSS-8 or PANSS-6 is a reliable, valid, sensitive to change measure, and scalable, and whether early improvement using them can predict response/remission. METHOD: Data were from 3 trials for 270 schizophrenia inpatients receiving antipsychotics. Internal consistency, validity, sensitivity to change, and scalability using PANSS-30, PANSS-8, and PANSS-6 at each assessment were examined. Early improvement was defined as at least 20% reduction of PANSS-30, PANSS-8, or PANSS-6 scores at week 2. Response was defined as at least 40% reduction of PANSS-30 and remission as a score of PANSS-8 ≤ 3 on each item at endpoint. Receiver operating characteristic analysis was used to determine which rating scale had better discriminative capacity. RESULTS: PANSS-8 and PANSS-6 showed acceptable internal consistency, were highly correlated with PANSS-30, and had sensitivity to change. PANSS-8 and PANSS-6 were scalable at each assessment, except for PANSS-6 at baseline. Early improvement using PANSS-8 or PANSS-6 had comparable predictive values with that of PANSS-30 for response/remission. CONCLUSION: PANSS-8 and PANSS-6 are clinically useful measures. Early improvement, regardless of whether PANSS-30, PANSS-8, or PANSS-6 is used, is a statistically significant predictor of response/remission.


Asunto(s)
Antipsicóticos/farmacología , Evaluación de Resultado en la Atención de Salud/normas , Escalas de Valoración Psiquiátrica/normas , Esquizofrenia/diagnóstico , Esquizofrenia/tratamiento farmacológico , Enfermedad Aguda , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Inducción de Remisión , Índice de Severidad de la Enfermedad
19.
Nat Mater ; 16(12): 1198-1202, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-29170556

RESUMEN

Graphene oxide (GO) membranes continue to attract intense interest due to their unique molecular sieving properties combined with fast permeation. However, their use is limited to aqueous solutions because GO membranes appear impermeable to organic solvents, a phenomenon not yet fully understood. Here, we report efficient and fast filtration of organic solutions through GO laminates containing smooth two-dimensional (2D) capillaries made from large (10-20 µm) flakes. Without modification of sieving characteristics, these membranes can be made exceptionally thin, down to ∼10 nm, which translates into fast water and organic solvent permeation. We attribute organic solvent permeation and sieving properties to randomly distributed pinholes interconnected by short graphene channels with a width of 1 nm. With increasing membrane thickness, organic solvent permeation rates decay exponentially but water continues to permeate quickly, in agreement with previous reports. The potential of ultrathin GO laminates for organic solvent nanofiltration is demonstrated by showing >99.9% rejection of small molecular weight organic dyes dissolved in methanol. Our work significantly expands possibilities for the use of GO membranes in purification and filtration technologies.

20.
Science ; 358(6362): 511-513, 2017 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-29074772

RESUMEN

In the field of nanofluidics, it has been an ultimate but seemingly distant goal to controllably fabricate capillaries with dimensions approaching the size of small ions and water molecules. We report ion transport through ultimately narrow slits that are fabricated by effectively removing a single atomic plane from a bulk crystal. The atomically flat angstrom-scale slits exhibit little surface charge, allowing elucidation of the role of steric effects. We find that ions with hydrated diameters larger than the slit size can still permeate through, albeit with reduced mobility. The confinement also leads to a notable asymmetry between anions and cations of the same diameter. Our results provide a platform for studying the effects of angstrom-scale confinement, which is important for the development of nanofluidics, molecular separation, and other nanoscale technologies.

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