RESUMEN
In contrast to gunshot wounds in skin and bone, the medico-legal literature pays little attention to the appearance of bullet penetration sites in abdominal organs. It was only in 1983 that Metter and Schulz published an article entitled "Morphological features of gunshot wounds in the liver and spleen." According to their observations, the organs in question showed stellate tears at the bullet penetration sites resembling skin wounds from contact shots to body regions having a bony support. The study presented simulated the real conditions by means of test shots to composite models consisting of porcine organs embedded in ballistic gelatin. The ammunition used was pistol cartridges 9 mm Luger with full metal jacket round nose bullets. The shots were video-documented with a high-speed camera in order to record the bullet's travel through the target. In addition, the composite models fired at underwent CT examinations followed by a macroscopic assessment of the organs. The study confirmed the findings of Metter and Schulz with regard to the star-like appearance of gunshot wounds in the liver and spleen. Likewise, the kidney showed radiating tears originating from the bullet path, whereas the wound track in pulmonary tissue was tube-shaped and lacked additional cracks. The varying wound patterns in parenchymatous organs can reasonably be explained as a consequence of the respective viscoelastic tissue properties.
Asunto(s)
Armas de Fuego , Heridas por Arma de Fuego , Animales , Porcinos , Balística Forense , Piel/lesiones , Hígado/lesionesRESUMEN
Magnetically doped topological insulators enable the quantum anomalous Hall effect (QAHE), which provides quantized edge states for lossless charge-transport applications1-8. The edge states are hosted by a magnetic energy gap at the Dirac point2, but hitherto all attempts to observe this gap directly have been unsuccessful. Observing the gap is considered to be essential to overcoming the limitations of the QAHE, which so far occurs only at temperatures that are one to two orders of magnitude below the ferromagnetic Curie temperature, TC (ref. 8). Here we use low-temperature photoelectron spectroscopy to unambiguously reveal the magnetic gap of Mn-doped Bi2Te3, which displays ferromagnetic out-of-plane spin texture and opens up only below TC. Surprisingly, our analysis reveals large gap sizes at 1 kelvin of up to 90 millielectronvolts, which is five times larger than theoretically predicted9. Using multiscale analysis we show that this enhancement is due to a remarkable structure modification induced by Mn doping: instead of a disordered impurity system, a self-organized alternating sequence of MnBi2Te4 septuple and Bi2Te3 quintuple layers is formed. This enhances the wavefunction overlap and size of the magnetic gap10. Mn-doped Bi2Se3 (ref. 11) and Mn-doped Sb2Te3 form similar heterostructures, but for Bi2Se3 only a nonmagnetic gap is formed and the magnetization is in the surface plane. This is explained by the smaller spin-orbit interaction by comparison with Mn-doped Bi2Te3. Our findings provide insights that will be crucial in pushing lossless transport in topological insulators towards room-temperature applications.
RESUMEN
The observation of the spin Hall effect triggered intense research on pure spin current transport. With the spin Hall effect, the spin Seebeck effect and the spin Peltier effect already observed, our picture of pure spin current transport is almost complete. The only missing piece is the spin Nernst (-Ettingshausen) effect, which so far has been discussed only on theoretical grounds. Here, we report the observation of the spin Nernst effect. By applying a longitudinal temperature gradient, we generate a pure transverse spin current in a Pt thin film. For readout, we exploit the magnetization-orientation-dependent spin transfer to an adjacent yttrium iron garnet layer, converting the spin Nernst current in Pt into a controlled change of the longitudinal and transverse thermopower voltage. Our experiments show that the spin Nernst and the spin Hall effect in Pt are of comparable magnitude, but differ in sign, as corroborated by first-principles calculations.
Asunto(s)
Hierro , TemperaturaRESUMEN
Advancing infrastructure of mountain regions allows not only well-prepared mountaineers, but also elderly people with pre-existing illness the stay at high altitudes. Based on the hypoxic conditions, low oxygen saturation values are reached, which cause severe hypoxemia in the tissue. Symptoms of acute mountain sickness appear even at moderate altitude, which are manifested during sleep.âPatients suffering from sleep apnea are at high risk, because of the obstructive ventilation disorder in combination with less oxygen availability. Concurrently, gender differences play a decisive role. Due to the respiratory stabilizing impact of estrogen, women are faster in adapting to altitude differences. A reduction of sleep duration and extended wake phases are shown, which causes lower sleep sufficiency. With continued rise of altitude, the arousal-index increases. For individual differences concerning altitude induced problems, individual acclimatization protocols are needed. Well prepared pre-acclimatization could prevent altitude induced sleep problems, as well as the treatment of such.
Asunto(s)
Mal de Altura/diagnóstico , Mal de Altura/terapia , Altitud , Trastornos del Sueño-Vigilia/diagnóstico , Trastornos del Sueño-Vigilia/terapia , Mal de Altura/complicaciones , Diagnóstico Diferencial , Medicina Basada en la Evidencia , Humanos , Trastornos del Sueño-Vigilia/etiología , Resultado del TratamientoRESUMEN
Within a combined experimental and theoretical study it is shown that the spin Hall angle of a substitutional alloy system can be continuously varied via its composition. For the alloy system Au_{x}Pt_{1-x} a substantial increase of the maximum spin Hall angle compared to the pure alloy partners could be achieved this way. The experimental findings for the longitudinal charge conductivity σ, the transverse spin Hall conductivity σ_{SH}, and the spin Hall angle α_{SH} could be confirmed by calculations based on Kubo's linear response formalism. Calculations of these response quantities for different temperatures show that the divergent behavior of σ and σ_{SH} is rapidly suppressed with increasing temperature. As a consequence, σ_{SH} is dominated at higher temperatures by its intrinsic contribution that has only a rather weak temperature dependence.
Asunto(s)
Sordera/diagnóstico , Países en Desarrollo , Testimonio de Experto/legislación & jurisprudencia , Paperas/diagnóstico , Enfermedades Profesionales/diagnóstico , Viaje/legislación & jurisprudencia , Sordera/etiología , Evaluación de la Discapacidad , Determinación de la Elegibilidad/legislación & jurisprudencia , Alemania , Humanos , Masculino , Persona de Mediana Edad , Paperas/complicaciones , Tanzanía , Acúfeno/diagnóstico , Acúfeno/etiología , Indemnización para Trabajadores/legislación & jurisprudenciaRESUMEN
PURPOSE: The success of trabeculectomy in glaucoma not sufficiently controlled by maximal medical therapy substantially depends on postoperative scarring of the filtering bleb. This process of scarring can be inhibited by antimetabolites like mitomycin C (MMC) and 5-fluorouracil (5-FU). The aim of this study is the evaluation of incidence and long-term outcome of corneal surface defects and intraocular pressure following MMC- or 5FU-trabeculectomy using different doses of postoperative 5FU. METHODS: A retrospective, non-randomised comparative study of 381 patients undergoing trabeculectomy with intraoperative application of either 5FU (group A, n = 169) or MMC (group B, n = 212) was performed. Based on the Wuerzburg bleb classification score (WBCS) for postoperative wound healing evaluation, 30 of these operations of group A (group B: n = 26) did not receive 5 FU postoperatively (controls), 67 (93) received up to 7 postoperative injections of 5 mg 5 FU (normal dosage group), and 72 (93) received more than 7 injections (high dosage group). Surface epithelial defects were routinely assessed by slit-lamp microscopy and fluorescein staining. Intraocular pressure (IOP) was measured by Goldmann applanation tonometry. RESULTS: In the normal dosage group the mean total dose of 5 FU was 25.8 ± 9.1 mg in group A (group B: 28.4 ± 7.5 mg) and in the high dosage group 54.2 ± 10.9 mg 5 FU (51.7 ± 11.8 mg), respectively. Increased doses of postoperative 5 FU induced more frequent corneal erosions in both groups. Corneal erosions were seen in controls in 16.7 % (26.9 %), in the normal dosage group in 55.2 % (47.3 %) and in the high dosage group in 77.8 % (59.1 %) in group A and group B, respectively. The incidence of a corneal erosion between group A and group B did not differ significantly (p = 0.074). The mean reduction of intraocular pressure in mmHg did not show a significant difference 12 months after trabeculectomy between controls and postoperative 5-FU operations. CONCLUSION: In eyes with beginning scarring of the filtering bleb after trabeculectomy the subconjunctival injection of 5-FU allows a similar reduction of intraocular pressure as in eyes without scarring. Corneal epitheliopathy following trabeculectomy and postoperative 5 FU is dose-dependent with higher doses leading to a higher incidence of corneal erosions. As serious corneal long-term complications are rare, risk-benefit analysis justifies the application of 5-FU after filtrating glaucoma surgery.
Asunto(s)
Antibióticos Antineoplásicos/administración & dosificación , Antibióticos Antineoplásicos/efectos adversos , Antimetabolitos Antineoplásicos/administración & dosificación , Antimetabolitos Antineoplásicos/efectos adversos , Enfermedades de la Córnea/inducido químicamente , Epitelio Corneal/efectos de los fármacos , Fluorouracilo/administración & dosificación , Fluorouracilo/efectos adversos , Presión Intraocular/efectos de los fármacos , Mitomicina/administración & dosificación , Mitomicina/efectos adversos , Complicaciones Posoperatorias/inducido químicamente , Trabeculectomía/efectos adversos , Anciano , Terapia Combinada , Enfermedades de la Córnea/diagnóstico , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Femenino , Humanos , Inyecciones Intraoculares , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/diagnóstico , Estudios RetrospectivosRESUMEN
The European Commission recently sponsored an international research and development project, in which three 'active' personal neutron dosemeters were developed. Comparative irradiation experiments showed good results with respect to sensitivity and energy dependence of the response.
Asunto(s)
Contaminación Radiactiva del Aire/análisis , Neutrones , Exposición Profesional/análisis , Monitoreo de Radiación/instrumentación , Monitoreo de Radiación/métodos , Electrónica , Diseño de Equipo , Unión Europea , Humanos , Cooperación Internacional , Desarrollo de Programa , Dosis de Radiación , Sensibilidad y EspecificidadRESUMEN
Ethidium bromide was used to study perturbations induced in salmon sperm DNA complexed with a series of platinum and palladium compounds obtained from chloro and orotic acid derivatives as leaving ligands. The antitumoral activity of these compounds against Sarcoma 180 cells grafted intraperitoneally into mice is correlated with their capacity to interact with DNA in vitro and to perturb its secondary structure. Nevertheless, among these compounds, [Pt(Dach)(3-methyl-orot)] and [Pt(Dach)(5-fluoro-orot)] do not interact with DNA in vitro and are inactive against Sarcoma 180 cells. This lack of activity originates from the fact that strong chelating properties of the ligand prevent hydrolysis of the compounds which are unable to give rise to aquo species which are the reactive ones. On the other hand, the interaction with DNA is not the only prerequisite in order that a compound be active towards tumour cells. In fact, cis-[Pd(NH3)2Cl2] and cis[Pd(Dach)Cl2] are not antitumoral. It is well known that the former undergoes an inactive trans-conformation and that the two compounds hydrolyse very fast assuming that they interact in vivo with a lot of molecules particularly proteins preventing them to reach the DNA, their pharmacological target. By contrast, [Pd(Dach)(3-methyl-orot)] (T/C = 267%) and [Pd(Dach)(5-fluoro-orot)] (T/C = 270%) display significant antitumour activity.
Asunto(s)
Antineoplásicos/farmacología , ADN de Neoplasias/efectos de los fármacos , Ácido Orótico/farmacología , Paladio/farmacología , Compuestos de Platino/farmacología , Animales , Sitios de Unión , División Celular/efectos de los fármacos , Trasplante de Células , ADN de Neoplasias/metabolismo , Hidrólisis , Cinética , Ligandos , Masculino , Ratones , Trasplante de Neoplasias , Ácido Orótico/química , Ácido Orótico/metabolismo , Paladio/química , Paladio/metabolismo , Compuestos de Platino/metabolismo , Salmón , Sarcoma 180/mortalidad , Sarcoma 180/patología , Espectrofotometría Ultravioleta , Espermatozoides/metabolismo , Relación Estructura-ActividadRESUMEN
In order to design and develop potential anticancer drugs involving the same structural pattern as platinum(II) antitumor complexes, complexes of palladium and platinum with 3-methyl-orotic acid as the leaving ligand have been synthesized. The study of the anticancer activity of these compounds toward L1210 leukemia and sarcoma 180 in mice is presented and discussed in terms of the nature of the ligand and the metal involved. The (3-methylorotato)(1,2-diamino-cyclohexane) palladium(II) has an activity (sarcoma 180) similar to that for cis-DDP itself. The crystal structure of (3-methylorotato)(dl-trans-1,2-diaminocyclohexane) platinum(II) is described.
Asunto(s)
Antineoplásicos/síntesis química , Compuestos Organometálicos/síntesis química , Compuestos Organoplatinos/síntesis química , Ácido Orótico/análogos & derivados , Animales , Supervivencia Celular/efectos de los fármacos , Cristalografía , Femenino , Leucemia L1210/tratamiento farmacológico , Ratones , Modelos Moleculares , Compuestos Organometálicos/farmacología , Compuestos Organoplatinos/farmacología , Ácido Orótico/síntesis química , Ácido Orótico/farmacología , Paladio/farmacología , Estereoisomerismo , Células Tumorales CultivadasRESUMEN
A range of palladium(II) complexes with chelating ligands were assayed for their antitumor activity against the tumors P388 and S180 in female mice. The complexes tested were [Pd(L)(ONO2)2] (L = 2,2'-bipyridyl,2-(aminoethyl)pyridine (aep), 2-(aminomethyl)pyridine (amp], [Pd(eth)Cl2] (eth = ethionine) and [Pd(dach)(Meorot)] (dach = trans-1,2-diaminocyclohexane, Meorot = dianion of 3-methylorotic acid). The complexes were administered in water except [Pd(dach)(Meorot)] which was a suspension in klucel. The LD0 values were greater than or equal to 100 mg/kg. None of the complexes were active against the P388 tumor. [Pd(L)ONO2)2] (L = aep, amp) showed marginal activity against S180, while [Pd(dach-)(Meorot)] had an optimal T/C of 267% at dose of 150 mg/kg with 2/10 survivors on day 60.
Asunto(s)
Antineoplásicos/farmacología , Quelantes/farmacología , Paladio/farmacología , Animales , Femenino , Ratones , Neoplasias Experimentales/tratamiento farmacológico , Relación Estructura-ActividadRESUMEN
The genotoxic effects of six cis-platinum(II)chloramine complexes with different alkyl substituents on their amine ligands have been measured using Escherichia coli. The toxicity and mutagenicity of these compounds were compared, after exposure of bacteria, to drug concentrations which gave known quantities of platinum-DNA lesions. The results permit several observations concerning structure-activity relations of platinum(II) complexes. Firstly, methyl substitution on the amine ligands of cis-diamminedichloro-platinum(II) (DDP) is reported to reduce its antitumor activity. The methyl group did not exert an effect in bacteria where the toxicity and mutagenicity of cis-bis(methylamine)dichloroplatinum(II) and DDP were equivalent. In fact, at equal levels of DNA binding, complexes with substituted amines were generally more toxic toward bacteria than DDP. Secondly, replacement of the chloro groups of DDP by nitrato ligands increased its toxicity and mutagenicity at a given level of DNA binding. Hence, although DDP and its dinitrato derivative have identical ammine ligands, they may form different platinum-DNA lesions in bacteria. Finally, cis-bis(cyclohexylamine)-dichloroplatinum(II) was unique among the compounds studied since it did not cause bacterial filamentation or mutagenesis. These results suggest that, although this compound binds to the bacterial genome, it may not induce the SOS response.
Asunto(s)
ADN Bacteriano/metabolismo , Escherichia coli/efectos de los fármacos , Mutágenos , Compuestos Organoplatinos/toxicidad , Platino (Metal)/toxicidad , Escherichia coli/metabolismo , Compuestos Organoplatinos/metabolismo , Platino (Metal)/metabolismo , Relación Estructura-ActividadRESUMEN
A critical review of the relevant literature revealed that the incidence of subarachnoid haemorrhage is increased in women taking oral contraceptives and the mortality rate is higher. The data concerning correlation between the use of oral contraceptives and other cerebrovascular disorders are less conclusive. Taking oral contraceptives seems to result in a higher risk of stroke, but there is no definite correlation to the incidence of strokes with a fatal outcome. However, in the case of the coexistence of more than one risk factor, including cigarette smoking, the risk of cerebrovascular disease is considerably increased for women using oral contraceptives. Age also seems to be a significant factor. Women older than 44 should avoid oral contraceptives in general; women between 35 and 44 should use oral contraceptives only if additional risk factors are absent, i.e. if they are non-smokers. Indeed, in the presence of this or other risk factors younger women should also avoid taking oral contraceptives.
Asunto(s)
Trastornos Cerebrovasculares/inducido químicamente , Anticonceptivos Orales/efectos adversos , Adulto , Isquemia Encefálica/inducido químicamente , Enfermedades de las Arterias Carótidas/inducido químicamente , Infarto Cerebral/inducido químicamente , Femenino , Estudios de Seguimiento , Humanos , Riesgo , Hemorragia Subaracnoidea/inducido químicamente , Insuficiencia Vertebrobasilar/inducido químicamenteRESUMEN
An initial loss of consciousness is of grave prognostic significance in patients with acute ischaemic cerebrovascular disorders, both as regards the early course as well as the long-term prognosis. The aim of this study was to assess the prognostic importance of an initial loss of consciousness in patients who had survived the acute stage. Thus, 133 out of 139 patients suffering from ischaemic cerebrovascular disorders who survived the first 3 weeks after a stroke were clinically re-examined after a mean follow-up period of more than two years. The other 6 patients had died as a result of a second stroke in the post-acute period. Patients with an initial loss of consciousness suffered cerebrovascular disturbances or fatal strokes in the follow-up period slightly more frequently than patients without an initial loss of consciousness. However, there were no convincing differences between the two groups. Indeed, on follow up, patients with an initial loss of consciousness were slightly less socially disabled than patients without an initial loss of consciousness. The results suggest that an initial loss of consciousness is no longer a factor of prognostic importance in patients who have survived the initial stage.
Asunto(s)
Isquemia Encefálica/complicaciones , Infarto Cerebral/complicaciones , Síncope/etiología , Femenino , Humanos , Ataque Isquémico Transitorio/complicaciones , Masculino , Persona de Mediana Edad , Pronóstico , Recurrencia , Insuficiencia Vertebrobasilar/complicacionesRESUMEN
Hormone parameters were evaluated in 14 children with cerebral manifestation of N.R. to find a possible involvement of the hypothalamo-pituitary axis. In addition to growth hormone and prolactin stimulation, tests of gonadotropic, thyreotropic and adrenocorticotropic function were performed. 6 patients had insufficient growth hormone secretory capacity, and 6 times an increased prolactin-stimulation was found; in one patient ACTH-reserve was diminished. A brain tumour was found in 5 of these 8 patients with impaired hormone results; however, in 3 cases pathologic results were found only after operation.
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Neoplasias Encefálicas/diagnóstico , Neurofibromatosis 1/diagnóstico , Adolescente , Niño , Preescolar , Femenino , Hormona Folículo Estimulante/sangre , Hormona del Crecimiento/sangre , Humanos , Hidrocortisona/sangre , Hormona Luteinizante/sangre , Masculino , Prolactina/sangre , Tirotropina/sangre , Tiroxina/sangreRESUMEN
Varied manipulatory-gnawing experience with nonfood objects facilitated later nut opening and insect predation in rats. Varied food consumption, which minimized manipulation, facilitated the hulling and consumption of sunflower seeds. Both treatments weakly facilitated forepaw food tablet grasping but neither treatment altered novel foods consumption or nest building. The data suggest that these two forms of prior experience contribute differentially to some later behaviours depending upon the sensory-motoric demands of the task and/or upon the intensity of food related stimulation.