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1.
J Orthop Traumatol ; 16(2): 93-7, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24374902

RESUMEN

BACKGROUND: Hip and wrist fractures are the most common orthopaedic injuries. Combined hip and distal radius fractures are an important clinical and public health problem, since mobilisation and rehabilitation is challenging and likely to be prolonged in this setting. Few studies have explored the influence of an associated wrist fracture in patients with hip fracture. We present the largest series of patients with concomitant hip and wrist fractures. We perform the first meta-analysis of the literature on patients with concurrent hip and wrist fractures. MATERIAL AND METHODS: In this single-centre retrospective study we compared 88 consecutive patients with simultaneous hip and wrist fractures with 772 consecutive patients who suffered isolated hip fractures. RESULTS: Patients with the combined fracture were of a similar age compared to those with isolated hip fracture. There were a significantly higher proportion of women in the cohort with both hip and wrist fractures (female:male ratio of 9:1 versus 4:1 p < 0.0001). The combination fracture group had a greater length of hospitalisation (18 vs 13 days p < 0.0001). The survivorship of both groups was not significantly different even after adjustment for age and gender. Meta-analysis of the literature showed female preponderance, increased length of stay but no significant difference in survival in patients with concomitant hip and wrist fractures. CONCLUSION: The combination fracture occurs much more commonly in women and patients require a greater length of hospitalisation. The patients who sustained simultaneous hip and wrist fractures experienced no statistically significant difference in survivorship when compared to those who suffer isolated hip fractures. This is not withstanding the presence of two fractures. This difference in mortality did not reach statistical significance. LEVEL OF EVIDENCE: Level III (retrospective comparative study).


Asunto(s)
Fracturas de Cadera/complicaciones , Fracturas del Radio/complicaciones , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Fijación Interna de Fracturas/métodos , Fracturas de Cadera/mortalidad , Fracturas de Cadera/cirugía , Humanos , Tiempo de Internación/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Fracturas del Radio/mortalidad , Fracturas del Radio/cirugía , Estudios Retrospectivos , Factores Sexuales , Tasa de Supervivencia
2.
Phys Rev Lett ; 112(2): 027201, 2014 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-24484042

RESUMEN

Cubic Mn2Ga films with the half-Heusler C1b structure are grown on V (001) epitaxial films. The phase is a soft ferrimagnet, with Curie temperature TC = 225 K and magnetization Ms=280 kA m(-1), equivalent to 1.65µB per formula. Adding ruthenium leads to an increase of TC up to 550 K in cubic Mn2Ru(x)Ga films with x = 0.33 and a collapse of the net magnetization. The anomalous Hall effect changes sign at x = 0.5, where the sign of the magnetization changes and the magnetic easy direction flips from in plane to perpendicular to the film. The Mn2Ru0.5Ga compound with a valence electron count of 21 is identified as a zero-moment ferrimagnet with high spin polarization, which shows evidence of half-metallicity.

3.
Bioorg Med Chem Lett ; 24(18): 4523-4528, 2014 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-25172417

RESUMEN

Osmolytes have been proposed as treatments for neurodegenerative proteinopathies including Alzheimer's disease. However, for osmolytes to reach the clinic their efficacy must be improved. In this work, copper(I)-catalyzed azide-alkyne cycloaddition chemistry was used to synthesize glycoclusters bearing six copies of trehalose, lactose, galactose or glucose, with the aim of improving the potency of these osmolytes via multivalency. A trehalose glycocluster was found to be superior to monomeric trehalose in its ability to retard the formation of amyloid-beta peptide 40 (Aß40) fibrils and protect neurons from Aß40-induced cell death.


Asunto(s)
Péptidos beta-Amiloides/antagonistas & inhibidores , Química Clic , Descubrimiento de Drogas , Glicoconjugados/farmacología , Neuronas/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Fragmentos de Péptidos/antagonistas & inhibidores , Trehalosa/análogos & derivados , Péptidos beta-Amiloides/metabolismo , Animales , Relación Dosis-Respuesta a Droga , Glicoconjugados/síntesis química , Glicoconjugados/química , Ratones , Ratones Endogámicos C57BL , Estructura Molecular , Neuronas/metabolismo , Neuronas/patología , Fármacos Neuroprotectores/síntesis química , Fármacos Neuroprotectores/química , Fragmentos de Péptidos/metabolismo , Relación Estructura-Actividad , Trehalosa/química
4.
J Colloid Interface Sci ; 629(Pt B): 814-824, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36195021

RESUMEN

HYPOTHESIS: Ortho and para water are the two nuclear isomers where the hydrogen protons align to give a total nuclear spin of 1 or 0. The equilibrium ratio of 3:1 is established slowly in freshly evaporated water vapour while the isomers behave distinct gasses, with their own partial pressures. Magnetic-field-induced ortho âŸ· para transformations are expected to alter the evaporation rate. EXPERIMENT: Evaporation from beakers of deionized water and a 6 M solution of urea is monitored simultaneously for periods from 1 to 60 h with and without a 500 mT magnetic field, while logging the ambient temperature and humidity. Balances with the two beakers are shielded in the same Perspex container. Many runs have been conducted over a two-year period. FINDINGS: The evaporation rate of water is found to increase by 12 ± 7% of in the field but that of water with dissolved urea decreases by 28 ± 6%. Two effects are at play. One is dephasing of the Larmor precession of adjacent protons on a water molecule in a field gradient, which tends to equalize the isomer populations. The other is Lorentz stress on the moving charge dipole, which can increase the proportion of the ortho isomer. From analysis of the time and field dependence of the evaporation, we infer that the ortho fraction is 39 ± 1% in fresh vapour from water and 60 ± 5% in fresh vapour from urea.

5.
Iran J Vet Res ; 23(4): 385-389, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36874178

RESUMEN

Background: Accidental electrocution was more common in animals and death was mostly due to shock and cardiac arrest. Survival of animals or humans could be possible if victims receive immediate medical support. Case description: A 3-year-old crossbred Jersey heifer was presented to the Emergency and Critical Care Medicine Referral Clinic of the Veterinary College and Research Institute, Orathanadu, with a history of accidental electrocution by broken high-tension overhead power transmission line during grazing in the paddy fields. The animal was dull and depressed, dark red, and some areas were charred in appearance on the dorsum and limbs. The animal showed difficulty walking due to the electrocution burn injury and was poorly responding to the surroundings. Clinical examination revealed subnormal temperature, polypnea, pale mucous membranes, ruminal atony, and arrhythmias on auscultation. Findings/treatment and outcome: On point of care (PoC) hematology testing, leukocytosis, neutrophilia, and microcytosis were observed. PoC electrolyte analysis revealed hypocalcemia (ionized calcium 0.89 mmol/L), mild hypochloremia, and severe hypokalemia (2.81 mmol/L). PoC biochemistry revealed hypoglycemia (41 mg/dl). PoC elevated levels of serum cardiac troponin (0.33 ng/dl) indicated cardiac damage. Aspartate aminotransferase (1794 U/L), CK-MB (699 U/L) and LDH (6.7 U/L) were also elevated. On PoC urinalysis, proteinuria, myoglobinuria, and glucosuria were observed. Evident clinical recovery, wound healing, and improvement in animal activities were observed. Conclusion: High-voltage electrocution injury is a serious type of accident with the potential risk of multi-organ damage and death. Early diagnosis of electrocution and immediate management enhances the expectancy of complete recovery.

6.
Med Biol Eng Comput ; 59(6): 1245-1259, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33988817

RESUMEN

Central serous chorioretinopathy (CSCR) is a chorioretinal disorder of the eye characterized by serous detachment of the neurosensory retina at the posterior pole of the eye. CSCR results from the accumulation of subretinal fluid (SRF) due to idiopathic defects at the level of the retinal pigment epithelial (RPE) that allows serous fluid from the choriocapillaris to diffuse into the subretinal space between RPE and neurosensory retinal layers. This condition is presently investigated by clinicians using invasive angiography or non-invasive optical coherence tomography (OCT) imaging. OCT images provide a representation of the fluid underlying the retina, and in the absence of automated segmentation tools, currently only a qualitative assessment of the same is used to follow the progression of the disease. Automated segmentation of the SRF can prove to be extremely useful for the assessment of progression and for the timely management of CSCR. In this paper, we adopt an existing architecture called SegCaps, which is based on the recently introduced Capsule Networks concept, for the segmentation of SRF from CSCR OCT images. Furthermore, we propose an enhancement to SegCaps, which we have termed as DRIP-Caps, that utilizes the concepts of Dilation, Residual Connections, Inception Blocks, and Capsule Pooling to address the defined problem. The proposed model outperforms the benchmark UNet architecture while reducing the number of trainable parameters by 54.21%. Moreover, it reduces the computation complexity of SegCaps by reducing the number of trainable parameters by 37.85%, with competitive performance. The experiments demonstrate the generalizability of the proposed model, as evidenced by its remarkable performance even with a limited number of training samples. Graphical abstract is mandatory please provide.


Asunto(s)
Coriorretinopatía Serosa Central , Coriorretinopatía Serosa Central/diagnóstico por imagen , Coroides/diagnóstico por imagen , Angiografía con Fluoresceína , Humanos , Líquido Subretiniano/diagnóstico por imagen , Tomografía de Coherencia Óptica
7.
Nature ; 430(7000): 630, 2004 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-15295588

RESUMEN

It is generally accepted that magnetic order in an insulator requires the cation to have partially filled shells of d or f electrons. Here we show that thin films of hafnium dioxide (HfO2), an insulating oxide better known as a dielectric layer for nanoscale electronic devices, can be ferromagnetic even without doping. This discovery challenges our understanding of magnetism in insulators, because neither Hf4+ nor O2- are magnetic ions and the d and f shells of the Hf4+ ion are either empty or full.

8.
Insect Mol Biol ; 18(4): 453-63, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19453767

RESUMEN

We have constructed the first genetic linkage map for the North American arboviral vector Culex tarsalis. 120 F(2) offspring from a cross between two colonies were genotyped using 25 microsatellites and six inter-simple sequence repeat (ISSR) markers. We resolved four linkage groups which likely correspond to two full-length chromosomes and two arms of the final chromosome. The longest linkage group contains the sex locus and corresponds to chromosome 3. Recombination rates around the sex locus were dramatically higher in females compared to males. The majority of microsatellite loci share sequence identity with regions of the Culex quinquefasciatus genome, whose assembly should aid in anchoring linkage groups to physical chromosomes. This map will aid in identification of loci involved with variable phenotypes in C. tarsalis including WNV susceptibility.


Asunto(s)
Culex/genética , Ligamiento Genético , Virus del Nilo Occidental/fisiología , Animales , Mapeo Cromosómico , Cromosomas/genética , Femenino , Marcadores Genéticos , Genotipo , Masculino
9.
Iran J Vet Res ; 20(3): 213-217, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31656528

RESUMEN

BACKGROUND: Diabetic ketoacidosis (DKA) is a disorder of carbohydrate metabolism that causes frequent urination, emaciation, extreme tiredness and dehydration. There is little or no information available on DKA in male goat (buck). The present study was carried out to report a rare case of DKA in a buck. CASE DESCRIPTION: A 1.5 year old buck was presented with anorexia and cough. On physical examination of buck showed fever, dullness, poor body condition and pale conjunctival mucous membrane. FINDINGS/TREATMENT AND OUTCOME: The peripheral blood smear revealed the mixed infection of Theileria sp. and Anaplasma sp. The blood picture showed anaemia and leukocytosis. The animal was treated with buparvaquone )2.5 mg/kg( and long acting oxytetracycline (20 mg/kg). Post treatment evaluation was done 7 days after initial treatment. Animal showed mild improvement in feed intake, the body temperature becomes normal, but showed tachycardia with weak pulse. Subsequently, animal showed severe emaciation with frequent urination. Urinalysis revealed glycosuria, ketonuria and acidic urine (pH = 6.0). Serum biochemistry revealed hyperglycemia, hypoinsulinemia, increased level of fructosamine and triglycerides and confirmed spontaneous DKA. It was treated with biphasic isophane insulin (1.0 IU/kg) twice a day, regularly. The blood glucose level becomes normal after insulin therapy. Animal resumed adequate feed intake, improvement in haemoglobulin (Hb), packed cell volume (PCV), total erythrocyte count (TEC), and weight gain was observed. CONCLUSION: This case study gains significance, due to its successful recovery after insulin treatment, but it requires lifelong insulin therapy to manage insulin dependent diabetes mellitus (IDDM) in this goat.

10.
New Microbes New Infect ; 32: 100613, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31737280

RESUMEN

Melioidosis caused by Burkholderia pseudomallei has become an important clinical threat, especially in Northern Australia and Southeast Asia. However, the genome information on this pathogen is limited. B. pseudomallei isolates identified from bloodstream infections from inpatients were subjected to whole-genome sequencing by IonTorrent PGM and MinION Oxford Nanopore sequencing technologies. Highly accurate complete genomes of two strains, VB3253 and VB2514, were obtained by a hybrid genome assembly method using both short and long DNA reads. Both isolates carried blaPenI and carbapenemase-encoding blaOXA-57 genes, although the isolates were susceptible to imipenem by E-test method with MIC 1 µg/mL. Multiple IS family transposases specific for all non-fermenting Gram-negative bacteria (NFGNBs)-especially IS3 and IS5, which facilitate mobilization of extended-spectrum ß-lactamase (ESBL) and carbapenemase genes-were carried in these genomes. This further adds to the complexity of gene transmission. These IS families were identified only upon hybrid genome assembly and would otherwise be missed.

11.
J Parasit Dis ; 43(2): 308-312, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31263338

RESUMEN

A study was carried out to determine the prevalence of haemoparasites in cattle in Cauvery delta region over a period of one year. A total of 228 giemsa stained blood smears were screened for the presence of haemoprotozoa, out of which 34 animals were found to be positive. An overall prevalence of haemoparasites in the sampled cattle were 14.9%, among this Anaplasma sp (8.3%), Babesia sp (3.95%), Theileria sp (2.19%) and Trypanosoma sp (0.44%) as single or mixed blood parasitic infections. In this study Anaplasmosis (14%) was highly prevalent during the winter season and Babesiosis (13.73%) was highly prevalent during summer months followed by Anaplasmosis (9.8%) and Theileriosis (7.8%), the lowest prevalence of Trypanosomiasis was observed during the rainy season. The seasonal variation in prevalence of haemoprotozoan disease might be due to influence of climatic factors on density of vector population in that geographical area. Haemogram revealed decreased level of haemoglobulin, packed cell volume and total erythrocyte count. The serum biochemistry revealed elevated level of liver enzyme Asparate transaminase enzyme. All haemoparasitaemic animals were treated with specific drugs and recovered successfully.

12.
Front Pharmacol ; 10: 881, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31474853

RESUMEN

Counterfeit and substandard medicines are recognized as one of serious threats to public health. The product quality of antibacterial medicine will compromise patients' recovery and increase the chance of antibacterial resistance. The review aims to provide a summary of low quality levofloxacin issues and the risk factors as well as suggesting the aspects of product quality that need to be regulated strictly. Quality of the active ingredient, levofloxacin, has an important role to contribute to successful therapy. The poor quality of raw material, directly and indirectly, causes treatment failure as the presence of insufficient dose, mislabeled content, and poor dissolution characteristics can lead to lower bioavailability. Identifying and reporting these factors can potentially help in improving the quality of drug marketed in various developing countries and may also reduce the incidences of treatment failure. Dissolution test is used for testing the dissolution profiles and the rate of drug release from solid formulation such as oral formulations, thus providing information regarding the in vivo performance of a formulation and its bioequivalence. On the other hand, quality-testing procedures are used for comparing the quality of products.

13.
Microbiol Res ; 162(4): 322-7, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-16580188

RESUMEN

In our systematic screening programme for marine actinomycetes, a bioactive Streptomycete was isolated from marine sediment samples of Bay of Bengal, India. The taxonomic studies indicated that the isolate belongs to Streptomyces chibaensis and it was designated as S. chibaensis AUBN1/7. The isolate yielded a cytotoxic compound. It was obtained by solvent extraction followed by the chromatographic purification. Based on the spectral data of the pure compound, it was identified as quinone-related antibiotic, resistoflavine (1). It showed a potent cytotoxic activity against cell lines viz. HMO2 (Gastric adenocarcinoma) and HePG2 (Hepatic carcinoma) in vitro and also exhibited weak antibacterial activities against Gram-positive and Gram-negative bacteria.


Asunto(s)
Antibacterianos/aislamiento & purificación , Antibacterianos/toxicidad , Benzopirenos/aislamiento & purificación , Benzopirenos/toxicidad , Streptomyces/química , Antibacterianos/farmacología , Benzopirenos/farmacología , Línea Celular Tumoral , Cromatografía , Sedimentos Geológicos/microbiología , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Humanos , India , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Análisis Espectral , Streptomyces/clasificación , Streptomyces/aislamiento & purificación , Streptomyces/fisiología
14.
Ann R Coll Surg Engl ; 99(2): 145-150, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27659368

RESUMEN

INTRODUCTION Intramedullary nailing is a common treatment for proximal femoral fractures. Fracture of the nail is a rare but devastating complication that exposes often frail patients to complex revision surgery. We investigated which risk factors predict nail failure. METHODS We reviewed all cases of nail breakage seen over a 10-year period in a single busy trauma unit; 22 nail fractures were seen in 19 patients. Comparison was made with a group of 209 consecutive patients who underwent intramedullary fixation of a proximal femur fracture with no nail breakage over a 2-year period. RESULTS In the fractured nail group, mean age was 70.4 years (range 55-88 years).The mean time to fracture was 10 months (range 2.5-23 months). Logistical regression was used to show that low American Society of Anesthesiologists (ASA) score, subtrochanteric fracture and pathological fracture were independent risk factors for nail fracture. CONCLUSIONS Young patients with a low ASA score are at highest risk of nail breakage. We advise close follow-up of patients with these risk factors until bony union has been achieved. In addition, there may be merit in considering other treatment options, such as proximal femoral replacement, especially for those with pathological fracture with a good prognosis.


Asunto(s)
Clavos Ortopédicos , Fracturas del Fémur , Fijación Intramedular de Fracturas , Complicaciones Posoperatorias , Anciano , Anciano de 80 o más Años , Falla de Equipo , Femenino , Fracturas del Fémur/diagnóstico por imagen , Fracturas del Fémur/cirugía , Fijación Intramedular de Fracturas/efectos adversos , Fijación Intramedular de Fracturas/instrumentación , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/diagnóstico por imagen , Complicaciones Posoperatorias/cirugía , Estudios Retrospectivos
15.
J Phys Chem B ; 120(35): 9410-21, 2016 09 08.
Artículo en Inglés | MEDLINE | ID: mdl-27494567

RESUMEN

A comprehensive study of ultrafast molecular relaxation processes of isomeric meso-(pyridyl) porphyrins (TpyPs) has been carried out by using femtosecond time-resolved emission and absorption spectroscopic techniques upon pumping at 400 nm, Soret band (B band or S2), in 4:1 dichloromethane (DCM) and tetrahydrofuran (THF) solvent mixture. By combined studies of fluorescence up-conversion, time-correlated single photon counting, and transient absorption spectroscopic techniques, a complete model with different microscopic rate constants associated with elementary processes involved in electronic manifolds has been reported. Besides, a distinct coherent nuclear wave packet motion in Qy state is observed at low-frequency mode, ca. 26 cm(-1) region. Fluorescence up-conversion studies constitute ultrafast time-resolved emission spectra (TRES) over the whole emission range (430-710 nm) starting from S2 state to Qx state via Qy state. Careful analysis of time profiles of up-converted signals at different emission wavelengths helps to reveal detail molecular dynamics. The observed lifetimes are as indicated: A very fast decay component with 80 ± 20 fs observed at ∼435 nm is assigned to the lifetime of S2 (B) state, whereas being a rise component in the region of between 550 and 710 nm emission wavelength pertaining to Qy and Qx states, it is attributed to very fast internal conversion (IC) occurring from B → Qy and B → Qx as well. Two distinct components of Qy emission decay with ∼200-300 fs and ∼1-1.5 ps time constants are due to intramolecular vibrational redistribution (IVR) induced by solute-solvent inelastic collisions and vibrational redistribution induced by solute-solvent elastic collision, respectively. The weighted average of these two decay components is assigned as the characteristic lifetime of Qy, and it ranges between 0.3 and 0.5 ps. An additional ∼20 ± 2 ps rise component is observed in Qx emission, and it is assigned to the formation time of thermally equilibrated Qx state by vibrational cooling/relaxations of excess energy within solvent. This relaxed Qx state decays to ground as well as triplet state by 7-8 ns time scale. The femtosecond transient absorption studies of TpyPs in three different excitations at S2 (400 nm), Qy (515 nm), and Qx (590 nm) along with extensive global and target model analysis of TA data exclusively generate the true spectra of each excited species/state with their respective lifetimes along with microscopic rate constants associated with each state. The following five exponential components with lifetime values of 65-70 fs, ∼0.3-0.5 ps, ∼20 ± 2 ps, ∼7 ± 1 ns, and 1-2 µs are observed which are associated with S2, Qy, hot Qx, thermally relaxed Qx, and lowest triplet (T1) states, respectively, when excited at S2, and four (Qy, hot Qx, thermally relaxed Qx, and lowest triplet (T1) states) and three (hot Qx, thermally relaxed Qx, and lowest triplet (T1) states) states are obtained when excited at 515 nm (Qy) and 590 nm (Qx), respectively, as expected. The TA results parallel the fluorescence up-conversion studies, and both the results not only compliment each other but also unveil the ultrafast internal conversion from S2 to Qy, S2 to Qx, and Qy to Qx for all three isomers in a similar fashion with nearly equal characteristic decay times.

16.
J Phys Condens Matter ; 28(48): 485001, 2016 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-27666311

RESUMEN

SrTiO3 plays a central role in oxide electronics. It is the substrate of choice for functional oxide heterostructures based on perovskite-structure thin-film stacks, and its surface or interface with a polar oxide such as LaAlO3 can become a 2D conductor because of electronic reconstruction or the presence of oxygen defects. Inconsistent reports of magnetic order in SrTiO3 abound in the literature. Here, we report a systematic experimental study aimed at establishing how and when SrTiO3 can develop a magnetic moment at room temperature. Polished (1 0 0), (1 1 0) or (1 1 1) crystal slices from four different suppliers are characterized before and after vacuum annealing at 750 °C, both in single-crystal and powdered form. Impurity content is analysed at the surface and in the bulk. Besides the underlying intrinsic diamagnetism of SrTiO3, magnetic signals are of three types-a Curie law susceptibility due to dilute magnetic impurities at the ppm level, a hysteretic temperature-dependent ferromagnetic impurity contribution, and a practically anhysteretic defect-related temperature-independent component that saturates in about 200 mT. The latter component is intrinsic. It is often the largest, reaching 10 µ B nm-2 of the surface area or more and dominating the magnetic response in low fields at room temperature. It is associated with defects near the surface, and can be destroyed by treatment with Tiron (C6H4Na2O8S2), an electron donor molecule that forms a strong complex with titanium at the surface. The origin of this unusual high-temperature ferromagnetic-like response is discussed.

17.
Nat Commun ; 7: 11015, 2016 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-26980456

RESUMEN

Magnetic interactions in solids are normally mediated by short-range exchange or weak dipole fields. Here we report a magnetic interaction that can propagate over long distances (∼10 nm) across a polar insulating oxide spacer. Evidence includes oscillations of magnetization, coercivity and field-cooled loop shift with the thickness of LaAlO3 in La0.67Sr0.33MnO3/LaAlO3/SrTiO3 heterostructures. Similar modifications of the hysteresis loop appear when two coupled films of La0.67Sr0.33MnO3 are separated by LaAlO3, or another polar insulator, but they are absent when the oxide spacer layer is nonpolar. The loop shift is attributed to strong spin-orbit coupling and Dzyaloshinskii-Moriya interaction at the interfaces. There is evidence from inelastic light scattering that the polar spacer mediates long-range transmission of orbital magnetization. This coupling mechanism is expected to apply for any conducting ferromagnetic oxide with mixed valence; in view of electron hopping frequency involved, it raises the prospect of terahertz tunability of magnetic coupling.

18.
Food Chem ; 199: 185-94, 2016 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-26775960

RESUMEN

Various food constituents have been proposed as disease-modifying agents for Alzheimer's disease (AD), due to epidemiological evidence of their beneficial effects, and for their ability to ameliorate factors linked to AD pathogenesis, namely by: chelating iron, copper and zinc; scavenging reactive oxygen species; and suppressing the fibrillation of amyloid-beta peptide (Aß). In this study, nine different food constituents (l-ascorbic acid, caffeic acid, caffeine, curcumin, (-)-epigallocatechin gallate (EGCG), gallic acid, propyl gallate, resveratrol, and α-tocopherol) were investigated for their effects on the above factors, using metal chelation assays, antioxidant assays, and assays of Aß42 fibrillation. An assay method was developed using 5-Br-PAPS to examine the complexation of Zn(II) and Cu(II). EGCG, gallic acid, and curcumin were identified as a multifunctional compounds, however their poor brain uptake might limit their therapeutic effects. The antioxidants l-ascorbic acid and α-tocopherol, with better brain uptake, deserve further investigation for specifically addressing oxidative stress within the AD brain.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Péptidos beta-Amiloides/antagonistas & inhibidores , Quelantes/farmacología , Depuradores de Radicales Libres/farmacología , Metales/metabolismo , Fragmentos de Péptidos/antagonistas & inhibidores , Encéfalo/metabolismo , Catequina/análogos & derivados , Catequina/farmacología , Curcumina/farmacología , Ácido Gálico/farmacología , Humanos
19.
J Ethnopharmacol ; 99(3): 349-52, 2005 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-15878247

RESUMEN

Phytochemical analysis of the leaves from Indian Suregada angustifolia (Baill. ex Muell. Arg.) Airy Shaw (Euphorbiaceae) resulted in the isolation and identification of six known compounds, viz. friedelin, epi-friedelinol, n-octacosanol, alpha-amyrin, beta-sitosterol and beta-sitosterol-3-beta-D-glucopyranoside. Aqueous (room temperature, boiled and autoclaved) and various solvent (methanol, chloroform and hexane) extracts of leaves were tested against 12 human pathogenic bacteria by the agar well-diffusion method. Aqueous extracts did not express any activity. Antibacterial activity was recorded in the order of methanol, hexane and chloroform extracts. Maximum activity recorded against Staphylococcus aureus (skin infections) in methanol and hexane extracts and moderate activity recorded against diarrhoea causing bacteria, Vibrio vulnificus (hexane extract) and Vibrio cholerae (chloroform extract).


Asunto(s)
Antibacterianos/farmacología , Extractos Vegetales/farmacología , Suregada/química , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Cloroformo/química , Hexanos/química , Humanos , India , Klebsiella pneumoniae/efectos de los fármacos , Klebsiella pneumoniae/crecimiento & desarrollo , Pruebas de Sensibilidad Microbiana/métodos , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Hojas de la Planta/química , Proteus vulgaris/efectos de los fármacos , Proteus vulgaris/crecimiento & desarrollo , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/crecimiento & desarrollo , Vibrio cholerae/efectos de los fármacos , Vibrio cholerae/crecimiento & desarrollo , Vibrio parahaemolyticus/efectos de los fármacos , Vibrio parahaemolyticus/crecimiento & desarrollo
20.
Ann R Coll Surg Engl ; 97(7): 513-8, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26274739

RESUMEN

Introduction Hyperlactataemia is associated with adverse outcomes in trauma cases. It is thought to be the result of anaerobic respiration during hypoperfusion. This produces much less energy than complete aerobic glycolysis. Low body temperature in the injured patient carries an equally poor prognosis. Significant amounts of energy are expended in maintaining euthermia. Consequently, there may be a link between lactate levels and dysthermia. Hyperlactataemia may be indicative of inefficient energy production and therefore insufficient energy to maintain euthermia. Alternatively, significant amounts of available oxygen may be sequestered in thermoregulation, resulting in anaerobic respiration and lactate production. Our study investigated whether there is an association between lactate levels and admission body temperature in hip fracture patients. Furthermore, it looked at whether there is a difference in the mean lactate levels between hip fracture patients with low (<36.5°C), normal (36.5-37.5°C) and high (>37.5°C) body temperature on admission, and for patients who have low body temperature, whether there is a progressive rise in serum lactate levels as body temperature falls. Methods The admission temperature and serum lactate of 1,162 patients presenting with hip fracture were recorded. Patients were divided into the euthermic (body temperature 36.5-37.5°C), the pyrexial (>37.5°C) and those with low body temperature (<36.5°C). Admission lactate and body temperature were compared. Results There was a significant difference in age between the three body temperature groups (p=0.007). The pyrexial cohort was younger than the low body temperature group (mean: 78 vs 82 years). Those with low body temperature had a higher mean lactate level than the euthermic (2.2mmol/l vs 2.0mmol/l, p=0.03). However, there was no progressive rise in serum lactate level as admission temperature fell. Conclusions The findings suggest that in hip fracture patients, the body attempts initially to maintain euthermia, incurring an oxygen debt. This would explain the difference in lactate level between the low body temperature and euthermic cohorts. The fact that there is no correlation with the degree of temperature depression and lactate levels indicates that the body does not fuel thermohomeostasis indefinitely with oxygen. Instead, in part, it abandons thermoregulatory mechanisms. Consequently, in this population, active rewarming may be indicated rather than depending on patients' own thermogenic ability.


Asunto(s)
Temperatura Corporal/fisiología , Fiebre/etiología , Fracturas de Cadera/fisiopatología , Hiperlactatemia/etiología , Hipotermia/etiología , Ácido Láctico/sangre , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Femenino , Fiebre/sangre , Fiebre/diagnóstico , Fracturas de Cadera/sangre , Fracturas de Cadera/complicaciones , Humanos , Hiperlactatemia/sangre , Hiperlactatemia/diagnóstico , Hipotermia/sangre , Hipotermia/diagnóstico , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
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