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1.
Bratisl Lek Listy ; 120(8): 566-568, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31379178

RESUMO

OBJECTIVE: Viperidae snakes are responsible for 95 % of the bites caused by exotic-bred snakes in our country. Their envenoming may be associated with a severe acute coagulation disorder - venom-induced consumption coagulopathy (VICC). Thus, its early prediction is vital for an adequate therapy including antivenom delivery. MATERIAL AND METHODS: Laboratory coagulation tests of 14 patients suffering from VICC were processed and statistically analyzed to evaluate the importance of individual parameters in the time after the bite. RESULTS: The pathological values of D-dimer (D-dim) and fibrinogen (FBG) were found to be the first indicators of VICC development, with a median time of 4.55 hours since the bite, while median values for prothrombin time and international normalized ratio (PT/INR), activated partial thromboplastin time (APTT), and thrombin time (TT) were 5.9 h, 8.15 h, and 5.5 h, respectively. In the first samples, the values of D-dim were found to be pathologically increased in all 14 patients, while pathological levels of FBG were seen only in 11 cases. PT/INR and APTT were prolonged in 8 and 6 cases, respectively. CONCLUSION: An increase in D-dim values was found to be the first parameter signaling developing VICC in all analyzed cases (Tab. 2, Ref. 12).


Assuntos
Testes de Coagulação Sanguínea , Coagulação Intravascular Disseminada/diagnóstico , Mordeduras de Serpentes/complicações , Viperidae , Animais , Humanos , Venenos de Serpentes
2.
Rozhl Chir ; 93(6): 307-10, 2014 Jun.
Artigo em Tcheco | MEDLINE | ID: mdl-25047969

RESUMO

INTRODUCTION: Due to the need for alternative arterial grafts suitable for the reconstruction of the coronary bloodstream, we conducted a morphological analysis of the descending branch of the lateral circumflex femoral artery (DBLCFA) using an AGCT scan. MATERIAL AND METHODS: Not only anatomical variations and the quantitative representation of sclerotic changes, but also the presence of a collateral system in the event of significant stenosis of the pelvic and femoral artery system were analysed. RESULTS: The results revealed favorable findings in the sense of the studied arteries length (9.3 cm on average), a relatively low anatomical variability and a very small percentage of the studied blood vessels participating in collateral blood flow, despite that 72% of tests revealed significant stenotic disease (stenosis of more than 50%) of the upper branch of lower limb arteries. CONCLUSION: According to the defined criteria, 68% of vessels were found to be suitable for grafting. We suppose that this number would be considerably higher in patients with only insignificant or no ischemic disease of the lower extremities.


Assuntos
Ponte de Artéria Coronária , Artéria Femoral/transplante , Idoso , Angiografia Coronária , Vasos Coronários/cirurgia , Feminino , Humanos , Masculino , Tomografia Computadorizada por Raios X
3.
J Phys Condens Matter ; 35(28)2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37015243

RESUMO

We report the first study of electrical resistivity, magnetization, and specific heat on YbCo2. The measurements on a single-phased sample of YbCo2bring no evidence of magnetic ordering down to 0.3 K in a zero magnetic field. The manifestations of low Kondo temperature are observed. The specific heat value divided by temperature,C/T, keeps increasing logarithmically beyond 7 J/mol K2with decreasing temperature down to 0.3 K without no sign of magnetic ordering, suggesting a very large electronic specific heat. Analysis of the magnetic specific heat indicates that the large portion of the low-temperature specific heat is not explained simply by the low Kondo temperature but is due to the strong intersite magnetic correlation in both the 3dand 4felectrons. Temperature-dependent measurements under static magnetic fields up to 7 T are carried out, which show the evolution of field-induced transition above 2 T. The transition temperature increases with increasing field, pointing to a ferromagnetic character. The extrapolation of the transition temperature to zero field suggests that YbCo2is in the very proximity of the quantum critical point. These results indicate that in the unique case of YbCo2, the itinerant electron magnetism of Co 3d-electrons and the Kondo effect within the vicinity of quantum criticality of Yb 4f-local moments can both play a role.

4.
J Phys Condens Matter ; 36(12)2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38056003

RESUMO

We report the properties of an A-site spinel magnet, CoAl2-xGaxO4, and analyze its anomalous, low-temperature magnetic behavior, which is derived from inherent, magnetically frustrated interactions. Rietveld analysis of the x-ray diffraction profile for CoAl2-xGaxO4revealed that the metallic ions were randomly distributed in the tetrahedral (A-) and octahedral (B-) sites in the cubic spinel structure. The inversion parameterηcould be controlled by varying the gallium (Ga) composition in the range 0.055 ⩽η⩽ 0.664. The composition-induced Néel-to-spin-glass (NSG) transition occurred between 0.05 ⩽η⩽ 0.08 and was verified by measurements of DC-AC susceptibilitiesχand thermoremanent magnetization (TRM) below the Néel transition temperatureTN. The relaxation rate and derivative with respect to temperature of TRM increased at bothTNand the spin glass (SG) transition temperatureTSG. The TRM decayed rapidly above and below these transitions. TRM was highly sensitive to macroscopic magnetic transitions that occurred in both the Néel and SG phases of CoAl2-xGaxO4. In the vicinity of the NSG boundary, there was a maximum of the TRM relaxation rate atTmax

5.
Vnitr Lek ; 58(9): 661-4, 2012 Sep.
Artigo em Tcheco | MEDLINE | ID: mdl-23094811

RESUMO

22 experts from the fields of gynecology and obstetrics, anesthesiology and resuscitation, intensive care, hematology and transfusion medicine has developed recommendations for diagnosis and procedure for life-threatening peripartum haemorrhage, which is still one of the most common causes of maternal mortality in childbirth. This guidelines, which is valid for the Czech Republic, supported by a total of 10 professional medical societies. There are based on new knowledge applicable at this time and is focused mainly on eliminating the most common causes of bleeding during delivery and prevention of haemorrhagic shock.


Assuntos
Hemorragia Pós-Parto/terapia , República Tcheca , Feminino , Humanos , Hemorragia Pós-Parto/diagnóstico , Hemorragia Pós-Parto/etiologia , Gravidez
6.
Prague Med Rep ; 112(3): 226-35, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21978783

RESUMO

A reptile holder based in the Czech Republic was bitten into his hand and foot by the Northeast saw-scaled viper (Echis pyramidum). The person arrived at the health institution after twenty hours for anuria. Despite the antivenom against the Asian Echis carinatum - the Echis pyramidum's close relative - was readily available and administered repeatedly, the envenoming continued to develop with subsequent coagulopathy, hepatopathy and respiratory failure. The effects of plasmapheresis and symptomatic therapy were positive, but only temporary. Continual renal replacement therapy and plasmapheresis were complicated by thrombotic occlusions of the device tubing set. A turning point arrived following repeated application of imported antivenom containing antigens against venom components of another African saw-scaled viper species, Echis leucogaster (the antivenom containing E. pyramidum antigens was not available). The clinical status, including complications, resolved following 30 days of hospitalization. The case further validates the geographical specifics of immunogenicity of venom components with similar clinical action in snakes of the same genus.


Assuntos
Antivenenos/uso terapêutico , Mordeduras de Serpentes/terapia , Viperidae , Adulto , Animais , Humanos , Masculino , Falha de Tratamento
7.
Prague Med Rep ; 112(4): 298-304, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22142525

RESUMO

Although very rare in a European context, a bite from the black mamba Dendroaspis polylepis is an event that poses an immediate threat to life. Given the content of neurotoxins in the snake's venom, the mortality of envenomation reaches 100% in almost every case if ventilation is not provided in a timely manner and adequate therapy initiated. The report describes a case of a snake breeder being envenomed. This 31-year-old man was bitten by a black mamba on his finger, and who subsequently developed clinical symptoms of envenoming typical for the species. Thanks to mechanical ventilation being employed promptly, with myorelaxation during generalized muscle fasciculations, and particularly owing to the eventual antivenin therapy, the patient's condition settled without consequences. In addition to describing the given case in detail, the paper discusses the composition and mechanisms of action of black mamba venom, while providing guidelines for adequate therapy.


Assuntos
Elapidae , Mordeduras de Serpentes , Adulto , Animais , Antivenenos/uso terapêutico , Venenos Elapídicos , Humanos , Masculino , Mordeduras de Serpentes/diagnóstico , Mordeduras de Serpentes/fisiopatologia , Mordeduras de Serpentes/terapia
8.
Prague Med Rep ; 111(1): 69-75, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20359440

RESUMO

Snakebites by the viper snake Cerastes cerastes are quite common across the world but rarely published with regard to their mostly benign course. The reported case study depicts the envenoming of a 36-year-old Czech man, a private herpetologist, who suffered snakebite to his finger. He developed a painful local reaction with hemorrhagic oedema. Subsequently, consumption coagulopathy with thrombocytopenia and haemolysis, colicky pain in the epigastrium and acute renal failure developed. Acute exudative pancreatitis was diagnosed on the third day after envenoming. Hemorrhagic oedema of the arm was complicated by a phlegmon. Symptomatic treatment including haemodialysis, fresh frozen plasma and thrombocytes was administered. Antivenom was not administered due to the delay in referral to the specialized unit. The patient recovered within one month, only postnecrotic defects of the finger persisted.


Assuntos
Pancreatite/etiologia , Mordeduras de Serpentes/complicações , Injúria Renal Aguda/etiologia , Adulto , Animais , Transtornos da Coagulação Sanguínea/etiologia , Esmalte Dentário , Humanos , Masculino , Trombocitopenia/etiologia , Viperidae
9.
Rozhl Chir ; 89(8): 501-3, 2010 Aug.
Artigo em Tcheco | MEDLINE | ID: mdl-21121145

RESUMO

Arterial revascularization of myocardium is a method of choice for surgical treatment of ischemic heart disease. The descending branch of lateral femoral circumflex artery (DBLFCA) is one of possible alternative autologous arterial grafts. Up to now, since 2003, 12 of these grafts have been harvested and used for revascularization of myocardium at our department. All grafts have been used as a Y-graft to the left internal mammary artery for revascularization of target vessels on lateral and inferior heart wall. Graft patency was controlled by the angio-CT procedure after three months. One of the grafts was occluded at the control. It means patency rate after three months was more than 91%. No other complications (such as problematic wound healing, paraesthaesia of lower leg, bleeding, spasm of the graft, infection etc.) were observed with graft harvesting. DBLCFA is a high-quality and safe alternative arterial graft, available for arterial revascularization of myocardium.


Assuntos
Artéria Femoral/transplante , Revascularização Miocárdica/métodos , Humanos , Coleta de Tecidos e Órgãos/métodos , Transplante Autólogo
10.
J Phys Condens Matter ; 32(42): 425601, 2020 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-32585641

RESUMO

There is an ongoing dispute in the community about the absence of a magnetic quantum critical point (QCP) in the noncentrosymmetric heavy fermion compound CeRhSi3. In order to explore this question we prepared single crystals of CeRh(Si1-x Ge x )3 with x = 0.05 and 0.15 and determined the temperature-pressure (T-p) phase diagram by means of measurements of the electrical resistivity. The substitution of isoelectronic but large Ge enforces a lattice volume increase resulting in a weakening of the Kondo interaction. As a result, the x = 0.05 and x = 0.15 compound exhibit a transition into the antiferromagnetic (AFM) at higher temperatures being T N = 4.7 K and T N1 = 19.7 K, respectively. Application of pressure suppresses T N (T N1) monotonically and pressure induced superconductivity is observed in both Ge-substituted compounds above p ⩾ 2.16 GPa (x = 0.05) and p ⩾ 2.93 GPa (x = 0.15). Extrapolation of T N(p) → 0 of CeRh(Si0.95Ge0.05)3 yields a critical pressure of p c ≈ 3.4 GPa (in CeRh(Si0.85Ge0.15)3 p c ≈ 3.5 GPa) pointing to the presence of an AFM QCP located deep inside the superconducting state.

11.
Science ; 161(3841): 599-601, 1968 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-5663306

RESUMO

Albino rats can reliably distinguish between the odors of stressed and unstressed rats. Five animals learned to interrupt an ongoing response when air from the cages of stressed rats was introduced into the test compartment, and to continue responding when air from unstressed rats was introduced. The discrimination does not seem to depend on recognition of odors of individual rats.


Assuntos
Discriminação Psicológica , Odorantes , Feromônios/fisiologia , Estresse Fisiológico , Animais , Fisiologia/instrumentação , Psicofisiologia , Ratos
12.
Sci Rep ; 9(1): 11214, 2019 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-31375730

RESUMO

Thin layers of silicon nanocrystals (SiNC) in oxide matrix with optimized parameters are fabricated by the plasma-enhanced chemical vapor deposition. These materials with SiNC sizes of about 4.5 nm and the SiO2 barrier thickness of 3 nm reveal external quantum yield (QY) close to 50% which is near to the best chemically synthetized colloidal SiNC. Internal QY is determined using the Purcell effect, i.e. modifying radiative decay rate by the proximity of a high index medium in a special wedge-shape sample. For the first time we performed these experiments at variable temperatures. The complete optical characterization and knowledge of both internal and external QY allow to estimate the spectral distribution of the dark and bright NC populations within the SiNC ensemble. We show that SiNCs emitting at around 1.2-1.3 eV are mostly bright with internal QY reaching 80% at room temperature and being reduced by thermally activated non-radiative processes (below 100 K internal QY approaches 100%). The mechanisms of non-radiative decay are discussed based on their temperature dependence.

13.
Micron ; 38(2): 170-5, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-16962333

RESUMO

Oxygenic photosynthesis of higher plants requires linear electron transport that is driven by serially operating Photosystem II and Photosystem I reaction centers. It is widely accepted that distribution of these two types of reaction centers in the thylakoid membrane is heterogeneous. Here, we describe two optical microscopic techniques that can be combined to reveal the heterogeneity. By imaging micro-spectroscopy at liquid nitrogen temperature, we resolved the heterogeneity of the chloroplast thylakoid membrane by distinct spectral signatures of fluorescence emitted by the two photosystems. With another microscope, we measured changes in the fluorescence emission yield that are induced by actinic light at room temperature. Fluorescence yield of Photosystem II reaction centers varies strongly with light-induced changes of its photochemical yield. Consequently, application of moderate background irradiance induces changes in the Photosystem II fluorescence yield whereas no such modulation occurs in Photosystem I. This contrasting feature was used to identify regions in thylakoid membranes that are enriched in active Photosystem II.


Assuntos
Microscopia de Fluorescência/métodos , Complexo de Proteína do Fotossistema I/análise , Complexo de Proteína do Fotossistema II/análise , Espectrometria de Fluorescência/métodos , Tilacoides/química , Processamento de Imagem Assistida por Computador , Microscopia Eletrônica de Transmissão , Tilacoides/ultraestrutura
14.
Sci Rep ; 7(1): 5763, 2017 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-28720812

RESUMO

Light extraction from a thin planar layer can be increased by introducing a two-dimensional periodic pattern on its surface. This structure, the so-called photonic crystal (PhC) slab, then not only enhances the extraction efficiency of light but can direct the extracted emission into desired angles. Careful design of the structures is important in order to have a spectral overlap of the emission with extraction (leaky) modes. We show that by fabricating PhC slabs with optimized dimensions from silicon nanocrystals (SiNCs) active layers, the extraction efficiency of vertical light emission from SiNCs at a particular wavelength can be enhanced ∼ 11 times compared to that of uncorrugated SiNCs-rich layer. More importantly, increased light emission can be obtained in a broad spectral range and, simultaneously, the extracted light can stay confined within relatively narrow angle around the normal to the sample plane. We demonstrate experimentally and theoretically that the physical origin of the enhancement is such that light originating from SiNCs first couples to leaky modes of the PhCs and is then efficiently extracted into the surrounding.

15.
Rev Sci Instrum ; 87(12): 126101, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28040916

RESUMO

The decay-time distribution deduced from luminescence kinetics experiments is, in general, dependent on the excitation pulse length as a direct consequence of different onset dynamics. We demonstrate this effect for the case of square excitation pulses applied to study the luminescence kinetics in Si nanocrystals. The short- and long-pulse limits are defined as 0.1 times the shortest lifetime in the distribution and 3 times the longest time, respectively. Outside these limits the decay-time distribution is independent on the pulse duration. In addition, we describe experimental conditions required to obtain a correct depiction of slow luminescence decay in the µs to ms time range.

16.
Leuk Res ; 25(12): 1137-42, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11684288

RESUMO

We report a unique case of aleukemic granulocytic sarcoma of the neck, originally misdiagnosed as non-Hodgkin's lymphoma (NHL), though chloroma was also suspected due to a greenish macroscopic appearance and the presence of myeloid chloroacetate esterase (CAE)+ cells. The proof of clonal T cell receptor gamma chain (TcRgamma) gene rearrangements in the recurring tumor was deemed to confirm the initial diagnosis of T cell NHL. Altogether five distinct types of clonal TcRgamma gene rearrangements were found in the tumor, bone marrow and peripheral blood. Only retrospectively, using RT-PCR, did we detect the acute myeloid leukemia subset-specific fusion gene AML1/ETO in the frozen samples of the relapsed tumor, as well as in the otherwise unaffected bone marrow and peripheral blood (representing 'minimal initial disease' in the latter two samples). Simultaneous staining verified that the neoplastic CAE+ cells and CD45RO+ T cells were different populations.


Assuntos
Rearranjo Gênico da Cadeia gama dos Receptores de Antígenos dos Linfócitos T , Proteínas de Fusão Oncogênica/genética , Sarcoma Mieloide/genética , Fatores de Transcrição/genética , Adulto , Subunidade alfa 2 de Fator de Ligação ao Core , Humanos , Masculino , Proteína 1 Parceira de Translocação de RUNX1 , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sarcoma Mieloide/imunologia
17.
J Chromatogr A ; 722(1-2): 47-57, 1996 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-9019306

RESUMO

Environmental concern is renewing interest in selective, waste-free extractions. A recent report demonstrated an improved extraction of phenobarbital by means of a specifically designed molecular receptor. In that work, the solvent was CHCl3. The current work is the first step in extending extractions based on molecular recognition to reusable solvents, namely plasticizers. Phenobarbital aqueous/organic partition coefficients, receptor solubility, and phenobarbital-receptor-formation constants in several plasticizers and in their CHCl3 solutions are reported. In addition, by a thermodynamic cycle, the free energy for transfer of the barbiturate-receptor complex from CHCl3 to plasticizers has been calculated. Finally, the data have been displayed in coordinate systems representing extraction efficiency and selectivity. The most selective extraction medium yielding useful extraction efficiency is dioctyl phthalate.


Assuntos
Fenobarbital/química , Plastificantes/química , Receptores de Droga/química , Fenômenos Químicos , Físico-Química , Ligação de Hidrogênio , Indicadores e Reagentes , Solubilidade , Solventes , Espectrofotometria Ultravioleta , Termodinâmica
18.
J Antibiot (Tokyo) ; 41(4): 469-80, 1988 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3372353

RESUMO

A set of four cerebrosides was isolated from a Pachybasium species and purified by preparative reversed-phase HPLC. All four products displayed activity in a natural product screen aimed at detecting novel cell wall-active antifungal agents based on synergy with the known glucan synthetase inhibitor, aculeacin. Based on degradation studies, fast atom bombardment mass spectrometry and 13C and high field 1H NMR techniques, the structure of the major cerebroside was determined to be (4E,8E)-N-D-2'-hydroxy-(E)-3'- hexadecenoyl-1-O-beta-D-glucopyranosyl-9-methyl-4,8-sphingadiene. The other components were found to be the corresponding 2'-hydroxypalmitic acid analog with one less double bond and an analogous pair containing 2'-hydroxystearic acid with and without the 3' double bond.


Assuntos
Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Cerebrosídeos/isolamento & purificação , Fungos Mitospóricos/metabolismo , Peptídeos Cíclicos , Trichoderma/metabolismo , Cerebrosídeos/farmacologia , Fenômenos Químicos , Química , Sinergismo Farmacológico , Espectroscopia de Ressonância Magnética
19.
J Antibiot (Tokyo) ; 38(5): 561-71, 1985 May.
Artigo em Inglês | MEDLINE | ID: mdl-4019308

RESUMO

A new antibacterial antibiotic complex, aridicin, was produced by a new genus, Kibdelosporangium aridum (SK&F-AAD-216). The individual factors, aridicins A, B and C, were isolated from the fermentation broth by an Amberlite XAD-7 resin extraction and purified by preparative reversed phase HPLC. The aridicins were found to be novel members of the glycopeptide class of antibiotics as exemplified by ristocetin and vancomycin, based on chemical and spectroscopic data, their molecular weights as determined by FAB mass spectrometry (1,786, 1,800 and 1,814), the detection of actinoidinic acid in their acid hydrolysates, and detailed TLC and HPLC comparisons with representative members of this class.


Assuntos
Actinomycetales/metabolismo , Antibacterianos , Antibacterianos/isolamento & purificação , Aminoácidos/análise , Antibacterianos/análise , Cromatografia Líquida de Alta Pressão , Glicopeptídeos/análise , Glicopeptídeos/isolamento & purificação , Peso Molecular , Conformação Proteica , Vancomicina/análise
20.
Neoplasma ; 24(4): 415-20, 1977.
Artigo em Inglês | MEDLINE | ID: mdl-904744

RESUMO

Thirty-six women with cancer of the breast were treated with infusion of cytotoxic drugs into the first portion of the subclavian artery adjuvant to radical or simple mastectomy. The patients were followed up for five years and the results were compared with a matched group of patients treated by mastectomy alone. There was no difference between the two groups in the overall mortality at the end of the fith year. The survival rates of patients with stage 3 carcinoma receiving adjuvant chemotherapy were in the first three years significantly better than those of the controls. No impairment of the wound healing was observed and the systemic side effects of the cytotoxic drugs were unimportant. In two patients serious neurologic complications developed and one patient died of pulmonary abscess.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias da Mama/terapia , Adulto , Idoso , Antineoplásicos/efeitos adversos , Encefalopatias/induzido quimicamente , Ciclofosfamida/administração & dosagem , Feminino , Seguimentos , Humanos , Infusões Intra-Arteriais , Leucopenia/induzido quimicamente , Mastectomia , Metotrexato , Pessoa de Meia-Idade , Derrame Pleural/etiologia , Cicatrização
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