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1.
Arch Microbiol ; 204(6): 326, 2022 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-35576077

RESUMEN

Microbes live in a complex communal ecosystem. The structural complexity of microbial community reflects diversity, functionality, as well as habitat type. Delineation of ecologically important microbial populations along with exploration of their roles in environmental adaptation or host-microbe interaction has a crucial role in modern microbiology. In this scenario, reverse ecology (the use of genomics to study ecology) plays a pivotal role. Since the co-existence of two different genera in one small niche should maintain a strict direct interaction, it will be interesting to utilize the concept of reverse ecology in this scenario. Here, we exploited an 'R' package, the RevEcoR, to resolve the issue of co-existing microbes which are proven to be a crucial tool for identifying the nature of their relationship (competition or complementation) persisting among them. Our target organism here is Frankia, a nitrogen-fixing actinobacterium popular for its genetic and host-specific nature. According to their plant host, Frankia has already been sub-divided into four clusters C-I, C-II, C-III, and C-IV. Our results revealed a strong competing nature of CI Frankia. Among the clusters of Frankia studied, the competition index between C-I and C-III was the largest. The other interesting result was the co-occurrence of C-II and C-IV groups. It was revealed that these two groups follow the theory of resource partitioning in their lifestyle. Metabolic analysis along with their differential transporter machinery validated our hypothesis of resource partitioning among C-II and C-IV groups.


Asunto(s)
Frankia , Microbiota , Frankia/genética , Filogenia , Plantas , Simbiosis/genética
2.
Arch Microbiol ; 204(1): 33, 2021 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-34923604

RESUMEN

Soil microbial diversity consisted of both culturable and non-culturable microbes. The cultivated microbes can be identified by conventional microbiological processes. However, that is not possible for the non-culturable ones. In those cases, next-generation sequencing (NGS)-based metagenomics become useful. In this study, we targeted two very popular tea gardens of Darjeeling hills-Makaibari (Mak) and Castleton (Cas). The main difference between these two study areas is the type of manure they use. Mak is solely an organic tea garden using all organic manure and fertilizers whereas Cas uses inorganic pesticides and fertilizers. The main aim was to compare the effect of organic manure over chemical fertilizers on the soil microbiomes. We have performed the 16 s metagenomics analysis based on the V3-V4 region. Downstream bioinformatics analysis including reverse ecology was performed. We found that the overall microbial diversity is higher in Mak compared to Cas. Moreover, the use of organic manure has reduced the population of pathogenic bacteria in Mak soil when compared to Cas soil. From the observations made through the metagenomics analysis of Mak and Cas soil samples, we may conclude that the application of organic manure supports the population of good bacteria in the soil which may eventually impact the tea garden workers' health.


Asunto(s)
Estiércol , Metagenómica , Humanos , India , Suelo ,
3.
Soft Matter ; 17(23): 5700-5710, 2021 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-34008689

RESUMEN

Electrophoresis of a charged dielectric hydrophobic colloid embedded in a charged hydrogel medium is addressed. A slip velocity condition at the particle surface is considered. The characteristic of the gel electrophoresis is different compared with the free-solution electrophoresis due to the presence of immobile charges of the gel medium, which induces a strong background electroosmotic flow and modifies the Debye layer of the colloid. The gel electrophoresis of the dielectric hydrophobic charged colloid is made based on first-order perturbation analysis. A closed form solution involving simple exponential integrals for the mobility is derived, which reduces to several existing mobility expressions under limiting conditions such as for the gel electrophoresis of hydrophilic particles and a hydrophobic colloid in free-solution electrophoresis. We find that the mobility reversal is achieved by varying the Debye length or gel permeability. For the present first-order perturbation analysis, unlike free-solution electrophoresis, the particle dielectric permittivity is found to influence the mobility. One of the intriguing features of the present study is the derivation of the simplified mobility expression, which can be easily computed for a given set of parameter values.

4.
Ann Pharm Fr ; 79(4): 418-430, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33515589

RESUMEN

OBJECTIVE: The research aims for finding the possibility of buccal delivery of celecoxib from an in situ mucoadhesive nanogel, and in vitro evaluation of the gel to evidence the enhanced permeation of drug from buccal mucosa. MATERIALS AND METHODS: Six formulations of celecoxib loaded NLCs were prepared using stearic acid and oleic acid in different ratio in aqueous solution of poloxamer by emulsion solvent evaporation technique. The physicochemical evaluations of the celecoxib loaded NLC (CeL-NLC) were carried out. The formulation F4 was selected as the best and subjected for FTIR, DSC, PXRD, and surface morphology study. In situ mucoadhesive gel was prepared with F4 in HPC, HPMC and Carbopol 934 gelling systems. The gels were evaluated for their mechanical and rheological properties and in vitro permeation studies through rabbit oral mucosa. RESULTS: The selected process at high shear homogenization could yield nanoparticles of desired physiochemical properties. The drug and excipients were compatible as disseminated from FTIR study. Transformation of the crystal form to amorphous form of celecoxib was revealed by the solid-state characterization studies. The AFM study unfold the formation of discrete asymmetric nano particles. All mucoadhesive gels found to have good mucoadhesion and rheological property with good in vitro permeation of drug. A comparative study and statistical analysis unveiled that gel containing Carbopol 934 was found to be the best mucoadhesive in situ gel of nano particles of celecoxib with enhanced permeation parameters. CONCLUSION: Therefore, the above in vitro evaluation of in situ mucoadhesive nano gel proved the potential of the formulation as a promising buccal delivery of celecoxib.


Asunto(s)
Nanopartículas , Poloxámero , Animales , Celecoxib , Sistemas de Liberación de Medicamentos , Geles , Nanogeles , Conejos
5.
Phys Rev Lett ; 125(13): 132501, 2020 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-33034500

RESUMEN

We report the first observation of two wobbling bands in ^{183}Au, both of which were interpreted as the transverse wobbling (TW) band but with different behavior of their wobbling energies as a function of spin. It increases (decreases) with spin for the positive (negative) parity configuration. The crucial evidence for the wobbling nature of the bands, dominance of the E2 component in the ΔI=1 transitions between the partner bands, is provided by the simultaneous measurements of directional correlation from the oriented states ratio and the linear polarization of the γ rays. Particle rotor model calculations with triaxial deformation reproduce the experimental data well. A value of spin, I_{m}, has been determined for the observed TW bands below which the wobbling energy increases and above which it decreases with spin. The nucleus ^{183}Au is, so far, the only nucleus in which both the increasing and the decreasing parts are observed and thus gives the experimental evidence of the complete transverse wobbling phenomenon.

6.
Psychol Med ; 50(11): 1862-1871, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-31422779

RESUMEN

BACKGROUND: Evidence has been accumulating regarding alterations in components of the endocannabinoid system in patients with psychosis. Of all the putative risk factors associated with psychosis, being at clinical high-risk for psychosis (CHR) has the strongest association with the onset of psychosis, and exposure to childhood trauma has been linked to an increased risk of development of psychotic disorder. We aimed to investigate whether being at-risk for psychosis and exposure to childhood trauma were associated with altered endocannabinoid levels. METHOD: We compared 33 CHR participants with 58 healthy controls (HC) and collected information about previous exposure to childhood trauma as well as plasma samples to analyse endocannabinoid levels. RESULTS: Individuals with both CHR and experience of childhood trauma had higher N-palmitoylethanolamine (p < 0.001) and anandamide (p < 0.001) levels in peripheral blood compared to HC and those with no childhood trauma. There was also a significant correlation between N-palmitoylethanolamine levels and symptoms as well as childhood trauma. CONCLUSIONS: Our results suggest an association between CHR and/or childhood maltreatment and elevated endocannabinoid levels in peripheral blood, with a greater alteration in those with both CHR status and history of childhood maltreatment compared to those with either of those risks alone. Furthermore, endocannabinoid levels increased linearly with the number of risk factors and elevated endocannabinoid levels correlated with the severity of CHR symptoms and extent of childhood maltreatment. Further studies in larger cohorts, employing longitudinal designs are needed to confirm these findings and delineate the precise role of endocannabinoid alterations in the pathophysiology of psychosis.


Asunto(s)
Experiencias Adversas de la Infancia/psicología , Amidas/sangre , Ácidos Araquidónicos/sangre , Endocannabinoides/sangre , Etanolaminas/sangre , Ácidos Palmíticos/sangre , Alcamidas Poliinsaturadas/sangre , Trastornos Psicóticos/sangre , Adulto , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Síntomas Prodrómicos , Escalas de Valoración Psiquiátrica , Trastornos Psicóticos/etiología , Factores de Riesgo , Adulto Joven
7.
Eur Cell Mater ; 40: 38-57, 2020 07 16.
Artículo en Inglés | MEDLINE | ID: mdl-32696976

RESUMEN

Surgical site infections after orthopaedic surgery using fracture fixation devices or endosseous implants create major surgical challenges with severe adverse effects, such as osteomyelitis. These infections are frequently caused by Staphylococcus aureus, often with high resistance to antibiotics, such as methicillin-resistant Staphylococcus aureus (MRSA). Due to the formation of impenetrable biofilms on implant surfaces, systemic antibiotic treatment has become exceedingly difficult. New solutions are pursued by combining several drugs using a controlled delivery system from specifically engineered implant surfaces. A sol-gel coating on titanium implants was previously developed with 20 wt % vancomycin and 30 wt % farnesol, with suppression of MRSA in vitro. The present study investigated the efficacy of sol-gel film coatings for controlled dual local delivery over 4 weeks utilising a rat infection model. The findings confirmed the viability of this new concept in vivo based on the differences observed between coatings containing vancomycin alone (SGV) and the dual-drug-containing coating with vancomycin and farnesol (SGVF). While both the SGVF and SGV coatings facilitated excellent preservation of the osseous microarchitecture, SGVF coating displayed a slightly higher potency for suppressing MRSA infiltration than SGV, in combination with a lower reactive bone remodelling activity, most likely by disturbing biofilm formation. The next step for advancing the concept of dual-drug delivery from sol-gel coatings to the clinic and confirming the promising effect of the SGVF coatings on reactive bone remodelling and suppressing MRSA infiltration is a study in a larger animal species with longer time points.


Asunto(s)
Sistemas de Liberación de Medicamentos , Farnesol/farmacología , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/microbiología , Vancomicina/farmacología , Animales , Huesos/diagnóstico por imagen , Huesos/microbiología , Huesos/patología , Materiales Biocompatibles Revestidos/farmacología , Farnesol/administración & dosificación , Farnesol/uso terapéutico , Masculino , Proyectos Piloto , Ratas Sprague-Dawley , Infecciones Estafilocócicas/diagnóstico por imagen , Vancomicina/administración & dosificación , Vancomicina/uso terapéutico , Microtomografía por Rayos X
8.
Lupus ; 28(14): 1656-1662, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31679449

RESUMEN

OBJECTIVE: Non-infectious myelitis in systemic lupus erythematosus (SLE) may be due to SLE myelitis, comorbid multiple sclerosis (MS), or neuromyelitis optica (NMO). We compared characteristics of these three conditions in SLE patients at a large academic institution. METHODS: We searched for neurologic diagnoses of SLE myelitis, NMO myelitis, and MS myelitis among 2297 patients with at least four 1997 American College of Rheumatology revised criteria for SLE between 2000 and 2015. Each subject was reviewed by a neurologist to confirm the underlying neurologic diagnosis. Demographic, clinical, laboratory, and radiographic data were extracted and compared using Fisher's exact test, analysis of variance, and Wilcoxon rank-sum test. RESULTS: Fifteen of the 2297 subjects with SLE (0.7%) met criteria for a spinal cord syndrome: seven had SLE myelitis, three had AQP4 seropositive NMO, and five had MS. The median SLE Disease Activity Index 2000 score at time of neurologic syndrome presentation was higher in SLE myelitis subjects (8, interquartile range (IQR) 7-16) compared with subjects with NMO (6, IQR 0-14) or MS (2, IQR 0-4), p = 0.02. Subjects with SLE myelitis were also more likely to have elevated anti-dsDNA antibodies at presentation (86%) compared with subjects with NMO (33%) or MS (0%), p = 0.03. CONCLUSION: Myelitis occurs rarely among patients with SLE. Compared with subjects with SLE + NMO and subjects with SLE + MS, subjects with SLE myelitis had higher SLE disease activity at presentation.


Asunto(s)
Lupus Eritematoso Sistémico/diagnóstico , Esclerosis Múltiple/diagnóstico , Neuromielitis Óptica/diagnóstico , Enfermedades de la Médula Espinal/complicaciones , Médula Espinal/patología , Adulto , Autoanticuerpos/análisis , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Sistema de Registros , Índice de Severidad de la Enfermedad
9.
Opt Lett ; 43(11): 2668-2671, 2018 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-29856388

RESUMEN

We have observed directional spontaneous emission of rhodamine 6G dye deposited on top of a silver grating and found that its angular distribution patterns were very different in TE and TM polarizations. The latter was related to the dispersion curves determined based on the polarized reflection spectra measured at multiple incidence angles. The most intriguing finding of this Letter was a resonance, which was coupled with TE-polarized light and determined the characteristic double-crescent patterns in the TE-polarized spontaneous emission. This observation, as well as nearly similar resonance observed in TM polarization, was tentatively explained in terms of leaky waveguide modes supported by a film of dye-doped polymer.

10.
J Acoust Soc Am ; 143(1): 260, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29390777

RESUMEN

The paper presents aeroacoustic results for the flow around finite-length circular cylinders at Reynolds number 84 770 for various length-to-diameter (L/D) ratios (= 3, 9, 20, 25, 30, and 35). The incompressible Navier-Stokes equations are solved using the large eddy simulation model of turbulence followed by acoustic predictions in the far field using Ffwocs Williams and Hawkings method. The comparisons of numerical and anechoic wind tunnel measurements show good agreement in terms of the aerodynamic forces and acoustic parameters such as tonal frequency, tonal sound pressure level, and overall sound pressure level. The cylinder L/D ratio was observed to be a significant parameter that controls vortex shedding and consequently the flow induced sound generation.

11.
Kathmandu Univ Med J (KUMJ) ; 16(62): 201-203, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30636766

RESUMEN

Eosinophilic Granuloma is the mildest and localized form of Langerhans Cell Histiocytosis and is characterized by clonal proliferation of Langerhans cells. It is a rare disease, accounting for less than 1% of all the osseous neoplasms. It has predilection for the axial skeleton and incidence in jaws is just 7.9%. It lacks pathognomonic clinical and radiographic trait and hence is difficult to make a correct diagnosis without histopathological and immunohistochemical examination. This report describes a case of Eosinophilic Granuloma of mandible in 30 years old male who presented with complain of unhealed extraction wound and was clinically diagnosed as chronic suppurative osteomyelitis. The final diagnosis of Eosinophilic Granuloma was made only after histopathological and immunohistochemical evaluations.


Asunto(s)
Granuloma Eosinófilo/diagnóstico , Mandíbula/patología , Osteomielitis/diagnóstico , Adulto , Diagnóstico Diferencial , Humanos , Inmunohistoquímica , Masculino , Enfermedades Raras
12.
Biochim Biophys Acta ; 1860(11 Pt A): 2484-2497, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27474203

RESUMEN

BACKGROUND: Autophagy is a critical process in acquiring drug resistance in solid tumors. However, the mechanisms by which autophagy modulate resistance to chemotherapy in bladder cancer remains poorly understood. MATERIAL AND METHODS: We have established cisplatin resistant patient derived primary cultured cells as well as T24 bladder cancer cells. The autophagy flux as well as the effect of chemotherapeutic agents, gemcitabine (GC) and mitomycin (MM) were evaluated in these cells. Side population analysis, tumorisphere assay and expression of stemness genes were also studied to evaluate the role of autophagy during chemoresistance. The role of cytokines in autophagy induced chemoresistance was demonstrated. RESULTS: Our results show that resistant cells have higher basal autophagic flux. GC and MM led to increase in autophagy and combination of autophagy inhibitors synergistically inhibited bladder cancer cell growth. When autophagy was inhibited, only IFN-γ level was decreased in cytokine array. Blocking IFN-γ decreased JAK2 expression and reduced the autophagy. Inhibition of JAK2 decreased the proportion of cancer stem cell enriched side population, tumor sphere forming ability and led to decrease in expression of stemness genes. Combined treatment with inhibitors of JAK2 and autophagy led to inhibition in cell growth, reduced the levels of inflammatory cytokines and decreased the resistance gene expression. CONCLUSION: GC and MM treatment increased autophagy process via IFN-γ mediated JAK2 and STAT3 pathway. GENERAL SIGNIFICANCE: These findings support a key role of the autophagy in drug resistance. Thus, autophagy-based, "customized" combinatorial approaches may effectively manage resistance and relapse in bladder cancer.


Asunto(s)
Autofagia , Resistencia a Antineoplásicos , Células Madre Neoplásicas/efectos de los fármacos , Neoplasias de la Vejiga Urinaria/metabolismo , Antineoplásicos/toxicidad , Línea Celular Tumoral , Cisplatino/toxicidad , Humanos , Janus Quinasa 2/metabolismo , Células Madre Neoplásicas/citología , Células Madre Neoplásicas/metabolismo , Factor de Transcripción STAT3/metabolismo
13.
Phys Rev Lett ; 118(19): 192501, 2017 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-28548517

RESUMEN

We present, for the first time, simultaneous determination of shear viscosity (η) and entropy density (s) and thus, η/s for equilibrated nuclear systems from A∼30 to A∼208 at different temperatures. At finite temperature, η is estimated by utilizing the γ decay of the isovector giant dipole resonance populated via fusion evaporation reaction, while s is evaluated from the nuclear level density parameter (a) and nuclear temperature (T), determined precisely by the simultaneous measurements of the evaporated neutron energy spectra and the compound nuclear angular momenta. The transport parameter η and the thermodynamic parameter s both increase with temperature, resulting in a mild decrease of η/s with temperature. The extracted η/s is also found to be independent of the neutron-proton asymmetry at a given temperature. Interestingly, the measured η/s values are comparable to that of the high-temperature quark-gluon plasma, pointing towards the fact that strong fluidity may be the universal feature of the strong interaction of many-body quantum systems.

14.
Eur J Nucl Med Mol Imaging ; 44(3): 500-508, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27872957

RESUMEN

BACKGROUND: Z-endoxifen is the most potent of the metabolites of tamoxifen, and has the potential to be more effective than tamoxifen because it bypasses potential drug resistance mechanisms attributable to patient variability in the expression of the hepatic microsomal enzyme CYP2D6. 18F-FES is a positron emission tomography (PET) imaging agent which selectively binds to estrogen receptor alpha (ER-α) and has been used for non-invasive in vivo assessment of ER activity in tumors. This study utilizes 18F-FES PET imaging as a pharmacodynamic biomarker in patients with ER+ tumors treated with Z-endoxifen. METHODS: Fifteen patients were recruited from a parent therapeutic trial of Z-endoxifen and underwent imaging with 18F-FES PET at baseline. Eight had positive lesions on the baseline scan and underwent follow-up imaging with 18F-FES 1-5 days post administration of Z-endoxifen. RESULTS: Statistically significant changes (p = 0.0078) in standard uptake value (SUV)-Max were observed between the baseline and follow-up scans as early as 1 day post drug administration. CONCLUSION: F-FES PET imaging could serve as a pharmacodynamic biomarker for patients treated with ER-directed therapy.


Asunto(s)
Neoplasias de la Mama Masculina/diagnóstico por imagen , Neoplasias de la Mama/diagnóstico por imagen , Estradiol/análogos & derivados , Neoplasias de los Genitales Femeninos/diagnóstico por imagen , Tomografía Computarizada por Tomografía de Emisión de Positrones , Radiofármacos , Adulto , Anciano , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Neoplasias de la Mama Masculina/tratamiento farmacológico , Neoplasias de la Mama Masculina/genética , Antagonistas de Estrógenos/uso terapéutico , Femenino , Neoplasias de los Genitales Femeninos/tratamiento farmacológico , Neoplasias de los Genitales Femeninos/genética , Humanos , Masculino , Persona de Mediana Edad , Receptores de Estrógenos/antagonistas & inhibidores , Receptores de Estrógenos/genética , Tamoxifeno/análogos & derivados , Tamoxifeno/uso terapéutico
15.
Psychol Med ; 47(10): 1691-1705, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28179039

RESUMEN

BACKGROUND: Substance use may increase the risk of non-adherence to antipsychotics, resulting in negative outcomes in patients with psychosis. METHOD: We aimed to quantitatively summarize evidence regarding the effect of cannabis use, the most commonly used illicit drug amongst those with psychosis, on adherence to antipsychotic medication. Studies were identified through a systematic database search. Adopting random-effects models, pooled odds ratios (OR) for risk of non-adherence to antipsychotic medications were calculated comparing: cannabis-users at baseline v. non-users at baseline; non users v. continued cannabis users at follow-up; non-users v. former users at follow-up; former users v. current users. RESULTS: Fifteen observational studies (n = 3678) were included. Increased risk of non-adherence was observed for cannabis users compared to non-users (OR 2.46, n = 3055). At follow-up, increased risk of non-adherence was observed for current users compared to non-users (OR 5.79, n = 175) and former users (OR 5.5, n = 192), while there was no difference between former users and non-users (OR 1.12, n = 187). CONCLUSIONS: Cannabis use increases the risk of non-adherence and quitting cannabis use may help adherence to antipsychotics. Thus, cannabis use may represent a potential target for intervention to improve medication adherence in those with psychosis.


Asunto(s)
Antipsicóticos/administración & dosificación , Uso de la Marihuana/efectos adversos , Cumplimiento de la Medicación , Trastornos Psicóticos/tratamiento farmacológico , Humanos
16.
Epidemiol Infect ; 145(1): 12-22, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27678150

RESUMEN

Measles elimination goals have been adopted in a range of countries, sub-regions, and regions since the WHO declared an elimination goal by 2015 or 2020. All countries attempt to achieve and maintain high coverage through routine immunization programmes. This routine strategy, however, does not ensure the elimination goal of measles. Many developed countries, such as the United States, that have succeeded in interrupting measles transmission earlier, are now experiencing outbreaks with an increasing number of cases. Using a stochastic, age-structured model of measles vaccination dynamics, we explore and characterize the transient dynamics of measles susceptibility in the years following the implementation of routine vaccination at the herd immunity threshold. We demonstrate how a population could face risks of potentially large outbreaks even within few years of vaccination. We characterize different risk profiles depending on the incidence pattern in the years prior to vaccination. These results suggest that the classic critical vaccination threshold is necessary to achieve herd immunity, but not sufficient to prevent long periods of transient, super-critical dynamics. Our results suggest the need of future work for more careful monitoring of the impacts of current immunization programmes, and developing models that take into account more complicated vaccination strategies, demographic factors, and population movements.


Asunto(s)
Brotes de Enfermedades , Transmisión de Enfermedad Infecciosa/prevención & control , Inmunidad Colectiva , Vacuna Antisarampión/administración & dosificación , Vacuna Antisarampión/inmunología , Sarampión/epidemiología , Sarampión/prevención & control , Factores de Edad , Femenino , Salud Global , Humanos , Masculino , Modelos Teóricos , Medición de Riesgo
17.
Nature ; 469(7328): 68-71, 2011 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-21179086

RESUMEN

Shell structure and magic numbers in atomic nuclei were generally explained by pioneering work that introduced a strong spin-orbit interaction to the nuclear shell model potential. However, knowledge of nuclear forces and the mechanisms governing the structure of nuclei, in particular far from stability, is still incomplete. In nuclei with equal neutron and proton numbers (N = Z), enhanced correlations arise between neutrons and protons (two distinct types of fermions) that occupy orbitals with the same quantum numbers. Such correlations have been predicted to favour an unusual type of nuclear superfluidity, termed isoscalar neutron-proton pairing, in addition to normal isovector pairing. Despite many experimental efforts, these predictions have not been confirmed. Here we report the experimental observation of excited states in the N = Z = 46 nucleus (92)Pd. Gamma rays emitted following the (58)Ni((36)Ar,2n)(92)Pd fusion-evaporation reaction were identified using a combination of state-of-the-art high-resolution γ-ray, charged-particle and neutron detector systems. Our results reveal evidence for a spin-aligned, isoscalar neutron-proton coupling scheme, different from the previous prediction. We suggest that this coupling scheme replaces normal superfluidity (characterized by seniority coupling) in the ground and low-lying excited states of the heaviest N = Z nuclei. Such strong, isoscalar neutron-proton correlations would have a considerable impact on the nuclear level structure and possibly influence the dynamics of rapid proton capture in stellar nucleosynthesis.

18.
Br J Psychiatry ; 209(2): 169-70, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27151070

RESUMEN

Relapse in psychosis typically necessitates admission to hospital placing a significant financial burden on the health service. Exposure to childhood trauma is associated with an increased risk of psychosis, however, the extent to which this influences relapse is unclear. This report summarises current research investigating the influence of childhood trauma on relapse requiring psychiatric hospital admission for psychosis. Seven studies were included; two revealed a positive association between childhood trauma and relapse admission, two studies found a negative relationship and three found no significant difference. Inconsistent current evidence suggests a need for further research in this area.


Asunto(s)
Adultos Sobrevivientes de Eventos Adversos Infantiles/estadística & datos numéricos , Hospitalización/estadística & datos numéricos , Hospitales Psiquiátricos/estadística & datos numéricos , Trastornos Psicóticos/terapia , Adulto , Humanos , Recurrencia
19.
Psychol Med ; 46(1): 177-88, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26353818

RESUMEN

BACKGROUND: Effect of cannabis use on memory function is a contentious issue, with effects being different in healthy individuals and patients with psychosis. METHOD: Employing a meta-analytic approach we investigated the effects of cannabis use on memory function in patients with psychosis and healthy individuals, and the effect of diagnosis, memory dimension and moderating factors. A total of 88 studies were identified through a systematic literature search, investigating healthy (n = 7697) and psychotic (n = 3261) individuals. Standardized mean differences between the cannabis user and non-user groups on memory tasks were estimated using random-effects models and the effect-size statistic Cohen's d. Effects of potential moderating factors were tested using mixed-effects models and subgroup analyses. RESULTS: We found that cannabis use was associated with significantly (p ⩽ 0.05) impaired global (d = 0.27) and prospective memory (d = 0.61), verbal immediate (d = 0.40) and delayed (d = 0.36) recall as well as visual recognition (d = 0.41) in healthy individuals, but a better global memory (d = -0.11), visual immediate recall (d = -0.73) and recognition (d = -0.42) in patients. Lower depression scores and younger age appeared to attenuate the effects of cannabis on memory. Cannabis-using patients had lower levels of depression and were younger compared with non-using patients, whilst healthy cannabis-users had higher depression scores than age-matched non-users. Longer duration of abstinence from cannabis reduced the effects on memory in healthy and patient users. CONCLUSIONS: These results suggest that cannabis use is associated with a significant domain-specific impairment in memory in healthy individuals but not in cannabis-using patients, suggesting that they may represent a less developmentally impaired subgroup of psychotic patients.


Asunto(s)
Agonistas de Receptores de Cannabinoides/farmacología , Dronabinol/farmacología , Trastornos de la Memoria/inducido químicamente , Memoria/efectos de los fármacos , Trastornos Psicóticos/fisiopatología , Adulto , Agonistas de Receptores de Cannabinoides/efectos adversos , Dronabinol/efectos adversos , Humanos
20.
Psychol Med ; 46(1): 27-45, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26370602

RESUMEN

The aim of this article is to summarize current evidence regarding alterations in the neuroendocrine stress response system and endocannabinoid system and their relationship in psychotic disorders such as schizophrenia. Exposure to stress is linked to the development of a number of psychiatric disorders including psychosis. However, the precise role of stress in the development of psychosis and the possible mechanisms that might underlie this are not well understood. Recently the cannabinoid hypothesis of schizophrenia has emerged as a potential line of enquiry. Endocannabinoid levels are increased in patients with psychosis compared with healthy volunteers; furthermore, they increase in response to stress, which suggests another potential mechanism for how stress might be a causal factor in the development of psychosis. However, research regarding the links between stress and the endocannabinoid system is in its infancy. Evidence summarized here points to an alteration in the baseline tone and reactivity of the hypothalamic-pituitary-adrenal (HPA) axis as well as in various components of the endocannabinoid system in patients with psychosis. Moreover, the precise nature of the inter-relationship between these two systems is unclear in man, especially their biological relevance in the context of psychosis. Future studies need to simultaneously investigate HPA axis and endocannabinoid alterations both at baseline and following experimental perturbation in healthy individuals and those with psychosis to understand how they interact with each other in health and disease and obtain mechanistic insight as to their relevance to the pathophysiology of schizophrenia.


Asunto(s)
Endocannabinoides/metabolismo , Sistema Hipotálamo-Hipofisario/metabolismo , Sistemas Neurosecretores/metabolismo , Sistema Hipófiso-Suprarrenal/metabolismo , Trastornos Psicóticos/metabolismo , Esquizofrenia/metabolismo , Estrés Psicológico/metabolismo , Humanos
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