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1.
Heliyon ; 10(7): e28815, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38596110

RESUMO

Detailed studies of the Li4GeО4-Li2CaGeО4 system by solid-phase syntheses of various compositions from pure Li4GeО4 to pure Li2CaGeО4 in the temperature range from 25 to 1125 °C is investigated for a first time. Solid state synthesis powders are characterized by X-ray and DSC/TG methods. Concentration and temperature two-phase regions of Li4GeО4 and Li2CaGeО4 as well as two-phase regions of Li2CaGeО4 and Li2+2xCa1-xGeO4 are established. Region of pure Li2+2xCa1-xGeO4 solid solution are detected too and it structure is investigated. Being structural analog to Li2+2xZn1-xGeO4 and Li2+2xMg1-xGeO4, Li2+2xCa1-xGeO4 has own specific local environment of the metal ions. The obtained results are compared with those for Li4GeО4-Li2ZnGeО4 system and for Li2+2xZn1-xGeO4 solid solution. The differences of the phase diagrams and structural features of the solid solutions are discussed.

2.
Chem Commun (Camb) ; 54(43): 5466-5469, 2018 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-29749409

RESUMO

Alluaudite sulfates are predicted to be high-voltage electrodes for lithium- and sodium-ion batteries. Herein, we provide the first experimental evidence for the operation of sodium cobalt-manganese sulfate, Na2+2δ(Co0.63Mn0.37)2-δ(SO4)3, at potentials higher than 4.0 V vs. Li/Li+. This fact comes as a result of the reduced cationic deficiency, redox properties of Co and Mn and stability of the alluaudite structure during alkali ion intercalation.

3.
Clin Microbiol Infect ; 22(12): 990-995, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27599690

RESUMO

There are only a limited number of antimicrobials for treating severe Clostridium difficile infection (sCDI). Tigecycline shows significant in vitro effect against C. difficile and is approved for management of complicated intra-abdominal infections. Our aim was to analyse the efficacy of tigecycline compared with standard therapy (oral vancomycin plus intravenous metronidazole) in adults treated for sCDI. A retrospective cohort study of such patients hospitalized at our department from January 2014 to December 2015 was performed. Patients receiving tigecycline monotherapy were compared with patients treated with standard therapy alone. Diagnosis and severity of CDI were determined according to guidelines of the European Society of Clinical Microbiology and Infectious Diseases (ESCMID). Primary outcome was clinical recovery, secondary outcomes were in-hospital and 90-day all-cause mortality and relapse, colectomy, and complication rates. Of the 359 patients hospitalized for sCDI, 90 (25.0%) were included, 45 in each group. Patients treated with tigecycline had significantly better outcomes of clinical cure (34/45, 75.6% vs. 24/45, 53.3%; p 0.02), less complicated disease course (13/45, 28.9% vs. 24/45, 53.3%; p 0.02), and less CDI sepsis (7/45, 15.6% vs. 18/45, 40.0%; p 0.009) compared with patients receiving standard therapy. Tigecycline usage was not associated with adverse drug reactions or need for colectomy. Rates of ileus, toxic megacolon, mortality, and relapse were similar between the two groups. Favourable outcomes suggest that tigecycline might be considered as a potential candidate for therapeutic use in cases of sCDI refractory to standard treatment.


Assuntos
Administração Intravenosa , Antibacterianos/uso terapêutico , Clostridioides difficile/efeitos dos fármacos , Enterocolite Pseudomembranosa/tratamento farmacológico , Minociclina/análogos & derivados , Administração Oral , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/administração & dosagem , Colectomia , Enterocolite Pseudomembranosa/diagnóstico , Feminino , Humanos , Infecções Intra-Abdominais/tratamento farmacológico , Masculino , Metronidazol/uso terapêutico , Pessoa de Meia-Idade , Minociclina/administração & dosagem , Minociclina/uso terapêutico , Recidiva , Estudos Retrospectivos , Sepse/tratamento farmacológico , Tigeciclina , Resultado do Tratamento , Vancomicina/uso terapêutico
4.
Phys Chem Chem Phys ; 17(15): 9919-26, 2015 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-25776803

RESUMO

The solvation dynamics after optical excitation of two phosphono-substituted coumarin derivatives dissolved in various solutions are studied by fluorescence up-conversion spectroscopy and quantum chemical simulations. The Kamlet-Taft analysis of the conventional absorption and emission spectra suggests weakening of the solvent-solute H-bonds upon optical excitation, which is in contrast to the results gained by the quantum simulations and earlier studies reported for coumarin derivatives without phosphono groups. The simulations give evidence that the solvent reorganisation around the excited fluorophore leads to partial electron transfer to the first solvation shell. The process occurs on a timescale between 1 and 10 ps depending on the solvent polarity and leads to a fast decay of the time-resolved emission signal. Using the ultrafast spectral shift of the time-dependent fluorescence we estimated the relaxation time of the H-bonds in the electronically excited state to be about 0.6 ps in water, 1.5 ps in ethanol and 2.8 ps in formamide.


Assuntos
Cumarínicos/química , Elétrons , Luz , Ácidos Fosforosos/química , Simulação por Computador , Transporte de Elétrons , Ligação de Hidrogênio , Modelos Moleculares , Espectrometria de Fluorescência
5.
J Phys Condens Matter ; 23(15): 156001, 2011 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-21451235

RESUMO

Single crystals of the mixed valence compound Pb3Ni1.5Mn5.5O15 were successfully grown. Polarized Raman spectroscopy revealed that they belong to the point group D(3d), in accordance with single-crystal x-ray diffraction data which were refined within the trigonal space group P3c1 (No. 165), with lattice parameters a = 9.941(3) Å and c = 13.543(3) Å. Strongly anisotropic long range magnetic order is established below 65 K.

6.
Spectrochim Acta A Mol Biomol Spectrosc ; 73(5): 929-35, 2009 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-19501545

RESUMO

The novel hydrogensquarate salt of 1,10-phenanthroline has been synthesized, isolated and structurally elucidated by single crystal X-ray diffraction. 1,10-Phenanthrolinium hydrogensquarate monohydrate (1) crystallizes in the non-centrosymmetric P2(1) space group. Its hydrogensquarate anions form a stable dimer by means of ((Sq))OHc...O=C((Sq)) hydrogen bonds with lengths of 2.509, 2.526, 2.510, and 2.524A. The solvent water molecule interacts with the anion dimers by means of strong and moderate hydrogen bonds HOHc...O=C((Sq)) with bond lengths of 2.782 and 2.845A, respectively. The 1,10-phenanthrolinium cation participates in NHc...OH(2) interactions with the water molecule (bond lengths of 2.810, 2.758, 2.779 and 2.760A). Surprisingly, compound contains four independent molecules in the unit cell. Optical properties were elucidated by means of linear-polarized solid-state IR-spectroscopy and UV-spectroscopy. In addition TGA, DSC, DTA data, positive and negative ESI mass spectra as well as (1)H- and (13)C NMR spectra are presented. Quantum chemical methods were used to calculate the electronic structure, vibrational data and electronic spectra as well as non-linear optical properties of neutral 1,10-phenanthroline and its protonated cation. Second harmonic generation measurements of the novel compound demonstrate that the compound possesses effective d coefficients of 1.9+/-0.5 pm V(-1), value that is about three times higher that of the low temperature form of potassium dideuterophosphate.


Assuntos
Fenantrolinas/química , Água/química , Varredura Diferencial de Calorimetria , Cristalografia por Raios X , Dimerização , Ligação de Hidrogênio , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Estrutura Molecular , Fenantrolinas/análise , Fenantrolinas/síntese química , Teoria Quântica , Espectrometria de Massas por Ionização por Electrospray , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta
7.
Artigo em Inglês | MEDLINE | ID: mdl-19261542

RESUMO

Two novel hydrogensquarates of 3-nicotinoyl (1) and 3-isonicotinoyl (2) coumarin have been synthesized and their structures and properties elucidated spectroscopically and structurally, using single crystal X-ray diffraction, linear-polarized solid-state IR-spectroscopy, UV-spectroscopy and negative ESI MS. Quantum chemical calculations were used to obtain the electronic structure, vibrational data and electronic spectra. The IR-spectroscopic elucidation is carried out by a comparison with the characteristics of corresponding neutral 3-nicotinoyl and 3-isonicotinoyl coumarins.


Assuntos
Cumarínicos/análise , Cumarínicos/química , Cristalografia por Raios X/métodos , Hidrogênio/análise , Hidrogênio/química , Ácidos Isonicotínicos/análise , Ácidos Isonicotínicos/química , Espectrofotometria/métodos , Modelos Moleculares , Estrutura Molecular
8.
Transpl Infect Dis ; 10(2): 106-9, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17605727

RESUMO

Invasive mycoses are pre-eminent causes of morbidity and mortality in the allogeneic stem cell transplant setting. In spite of novel diagnostic modalities, the timely and specific identification of invasive mycoses still remains challenging. We analyzed the case history of 97 consecutive patients receiving 103 allogeneic stem cell transplants between January 2003 and October 2006 performed by a single team at 2 transplant centers in Budapest, Hungary. All patients with febrile neutropenia not responding to broad-spectrum antibacterial therapy received amphotericin B deoxycholate empirically. In cases of proven or probable invasive aspergillosis, intravenous voriconazole was instituted. Patients who failed to improve on initial therapy were treated with an antifungal combination, while responders were switched to oral voriconazole. A total of 38 patients died following allografting. Both centers had an autopsy rate of 100% due to central health care regulations. An infectious cause of death could be identified in 15 cases, invasive fungal disease being the most prevalent and accounting for 10 fatalities. Six patients died of invasive aspergillosis, while invasive candidiasis and mucormycosis led to a fatal outcome in 2 cases each. Despite the regular use of galactomannan antigen detections and imaging, an ante mortem diagnosis of proven/probable invasive fungal disease could only be established in 4 of 10 autopsy-verified cases (aspergillosis: 3, candidiasis: 1, mucormycosis: 0). In the remaining 6 patients, deep mycoses were missed clinically and were revealed only by postmortem histology. Present diagnostic and therapeutic strategies still seem to be suboptimal for the management of invasive fungal diseases in the high-risk allogeneic stem cell transplant population.


Assuntos
Antifúngicos/uso terapêutico , Aspergilose/diagnóstico , Candidíase/diagnóstico , Transplante de Células-Tronco Hematopoéticas , Micoses/diagnóstico , Administração Oral , Adolescente , Adulto , Antifúngicos/administração & dosagem , Aspergilose/tratamento farmacológico , Aspergilose/mortalidade , Autopsia , Candidíase/tratamento farmacológico , Candidíase/mortalidade , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Micoses/tratamento farmacológico , Micoses/mortalidade , Transplante Homólogo , Resultado do Tratamento
9.
J Ethnopharmacol ; 105(1-2): 286-93, 2006 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-16545928

RESUMO

The ethnobotanical survey conducted in this study showed that 21 plant species belonging to 14 families are used in traditional medical practice in Limpopo Province, South Africa, for the treatment of diarrhoea. Methanol, ethanol, acetone and hot water extract from different plant parts (leaves, roots, bark and stem rhizome), of several of these plants (Indigofera daleoides, Punica granatum, Syzygium cordatum, Gymnosporia senegalensis, Ozoroa insignis, Elephantorrhiza elephantina, Elephantorrhiza burkei, Ximenia caffra, Schotia brachypetala and Spirostachys africana), were screened for antibacterial activity against Vibro cholera, Escherichia coli and Staphylococcus aureus, Shigella spp., Salmonella typhi. The antibacterial activity was determined by agar-well diffusion method and expressed as the average diameter of the zone of inhibition of bacterial growth around the wells. The minimum inhibitory concentration (MIC) of active extracts was determined by using the micro-plate dilution assay. Most of the extracts showed relatively high antibacterial activity against most of the tested microorganisms with the diameter of inhibition zones ranging between 10 and 31 mm. Of the plants studied, the most active extracts were those obtained from Punica granatum and Indigofera daleoides. All extracts from two plants, namely, Punica granatum and Ozoroa insignis, were active against all bacterial strains while only organic extracts of Indigofera daleoides inhibited the growth of all tested microorganisms. Water extract of Punica granatum were equally active as organic extracts against bacteria such as Staphylococcus aureus, Shigella sonnei and Shigella flexneri. All extracts of Elephantorrhiza elephantina, Elephantorrhiza burkei and Ximenia caffra and Schotia brachypetala were not active against Escherichia coli and Salmonella typhi. The MIC values for active extracts ranged between 0.039 and 0.6 mg/ml. The results obtained appeared to confirm the antibacterial potential of the plants investigated, and their usefulness in the treatment of diarrhoea.


Assuntos
Antibacterianos/uso terapêutico , Diarreia/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Plantas Medicinais , Humanos , Testes de Sensibilidade Microbiana , Plantas Medicinais/classificação , África do Sul
13.
Cent Eur J Public Health ; 9(3): 130-2, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11505734

RESUMO

This paper deals with the study of the effect of 135 min exposure to noise with intensity Leq 95 dB(A) in experimental conditions. Three experimental sessions: before, at the onset, and at the end of the noise exposure were conducted. The comparison of heart rate variability (HRV) parameters before and on the onset of the experiment showed tendency for significant decrease of the cardiointervals variability parameters: standard deviation (SD), sum of positive differences between successive cardiointervals (S), total wave energy in the cardiotachogram (S*Ns), mean difference between successive cardiointervals (V). Statistically significant increase of the mean value was found at HRV parameters related to the distribution of the cardiointervals: control adequacy parameter (IARP), equilibrium autonomic parameter (IVE), autonomous balance (IVB), homeostasis parameter (HI). At the end of the third experimental session HRV parameters were almost restored, but they did not achieve the initial values. An elevation of the sympathetic activity under noise exposure effect was found. In this aspect, the heart rate variability parameters were interpreted as a sensitive indicator for the quality of cardiac rhythm and they can be used for assessment of the functional status and the level of preserving of the adaptive reserves of the investigated persons.


Assuntos
Frequência Cardíaca , Ruído , Adulto , Humanos , Masculino
14.
Laterality ; 5(1): 69-75, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15513132

RESUMO

The study covered 25 left-handed and 27 right-handed clinically healthy females aged between 47 and 55 years during normal menopause. It was carried out in the third year from the beginning of amenorrhoea. The levels of the follicle-stimulating hormone, luteinising hormone, proclactin, estradiol, and progesterone were determined by means of enzyme-immunological methods with IMX (Abbott, USA) and Serozyme I (Biochem Immunosystem Diagnostica, USA) apparatuses. It was established that in left-handed women the serum concentrations both of the follicle-stimulating hormone and luteinising hormone were significantly higher (P <.001), and those of prolactin, estradiol, and progesterone much lower (P <.001), as compared to the right-handed women.

15.
Brain Lang ; 68(1-2): 362-9, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10433782

RESUMO

This study explores the role of semantic transparency and morphological headedness in the on-line visual recognition of French and Bulgarian compounds using a constituent repetition priming paradigm. The results reported show significant constituent priming effects for both languages. Moreover, distinct priming patterns emerged, demonstrating that the semantic transparency of individual constituents, their position in the string, and morphological headedness interact in the processing of compounds.


Assuntos
Psicolinguística , Adulto , Bulgária , Comparação Transcultural , Feminino , França , Humanos , Masculino , Tempo de Reação , Semântica , Percepção Visual/fisiologia
16.
Orv Hetil ; 139(8): 409-12, 1998 Feb 22.
Artigo em Húngaro | MEDLINE | ID: mdl-9524423

RESUMO

In patients with hematological malignancies invasive mycoses occur frequently. In this retrospective study autopsy and histopathology material of 171 patients with hematological malignancy who had died between 1994 and 1996 at the 1st Department of Internal Medicine (Hematology), St. László Hospital, Budapest was analysed. In cases with invasive fungal infection post mortem results were compared to clinical and microbiological data. Through the three years' period an invasive mycosis could be confirmed in 33 patients by autopsy. Aspergillosis occurred in 21, candidiasis in 11, other fungal infections in 2 cases, a double infection was seen in 1 patient. The incidence was 19.2% (in invasive candidiasis: 6.4%, in aspergillosis 12.2%). Invasive aspergillosis most frequently was seen in the lung (71%), while candidiasis occurred mainly in the intestinal tract (42%). Cultures for mycology were collected from the autopsy material of 9 patients, of which 8 gave positive results. A previous fungal colonisation results was confirmed in 23 patients, but based on colonisation conclusions rarely could be driven concerning the species causing invasive infection. Sensitivity of Aspergillus antigen and antibody tests was 45 and 50%, respectively. Predisposing factors for invasive aspergillosis and candidiasis were similar, except for duration of neutropenia (24 vs. 12 days, p < 0.004). The antifungal drug most frequently used was amphotericin B. We observed a persisting infection in invasive pulmonary aspergillosis and chronic disseminated candidiasis in spite of the administration of a cumulative dosis of 1-2 g. Most frequently Aspergillus infections--primarily that of the lung--can be seen. Presence of invasive mycoses can usually be confirmed in vivo, but an early diagnosis still remains unsolved.


Assuntos
Candidíase/etiologia , Leucemia/complicações , Linfoma/complicações , Micoses/etiologia , Aspergilose/etiologia , Aspergilose/patologia , Autopsia , Candidíase/patologia , Humanos , Leucemia/microbiologia , Leucemia/patologia , Linfoma/microbiologia , Linfoma/patologia , Micoses/patologia
17.
Cent Eur J Public Health ; 5(3): 143-6, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9386902

RESUMO

A statistically significant correlation between chronic (tonic) distress (expressed by long-term depression of heart rate variability-HRV) and the increase of the serum lipid level was found in the experimental group (39 clinically healthy subjects with hypercholesterolaemia; 16 women and 23 men; mean age 42.4 +/- 2.45 years). A statistically significant relationship was found also between the experimental and control group (39 healthy normocholesterolaemic subjects; 18 women and 21 men; mean age 43.7 +/- 2.18 years) when comparing distress indicating HRV-based measurements. Significant predictors of HRV depression were: total cholesterol and low-density lipoprotein cholesterol. The effect of a 3-month special diet served to 17 subjects selected from the experimental group led to a decrease of serum lipids but did not influence substantially HRV parameters. It can be concluded that HRV parameters reflecting stress reaction correlate with atherogenic serum lipids; their separate follow-up (which is quicker, easier and cheaper) can be used for prediction of cardiovascular health risk and probably for disorders in serum lipid metabolism.


Assuntos
Frequência Cardíaca , Hipercolesterolemia/fisiopatologia , Adulto , Feminino , Humanos , Hipercolesterolemia/dietoterapia , Lipídeos/sangue , Masculino , Valor Preditivo dos Testes , Análise de Regressão
18.
Int J Neurosci ; 86(1-2): 143-9, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8828067

RESUMO

A total of 1985 women aged between 55 and 65 were distributed into two groups (145 left-handers and 1840 right-handers). They were asked to complete a questionnaire on the appearance of menopause, duration of menopausal transition and age of menopause. In left-handed women a significantly earlier appearance of premenopause was established together with a shorter menopause transition and an earlier occurrence of menopause. These results give grounds for a correlation between handedness, functional brain asymmetry, respectively and the genetically determined fading away of ovary steroidogenesis associated with the appearance and progression of the climacterium. In light of the available literature we assume that progressive reduction in ovarian function during climacterium is coupled with possible specific functioning of the hypothalamo-pituitary-gonadal axis, dependent on the type of hemispheric asymmetry.


Assuntos
Envelhecimento/fisiologia , Encéfalo/fisiologia , Climatério/fisiologia , Lateralidade Funcional/fisiologia , Idoso , Feminino , Humanos , Menopausa/fisiologia , Pessoa de Meia-Idade , Pré-Menopausa/fisiologia
19.
Orv Hetil ; 137(29): 1587-90, 1996 Jul 21.
Artigo em Húngaro | MEDLINE | ID: mdl-8757071

RESUMO

UNLABELLED: This is the first report in Hungary about meningitis caused by multiply-resistant Streptococcus pneumoniae in a 54 year old woman. The Streptococcus pneumoniae serotype 19A was highly resistant to penicillin, ampicillin, chloramphenicol, cefuroxime and intermediate resistant to ceftriaxone. The antibiotic treatment was started with penicillin and ampicillin. The antibiotic treatment was changed to vancomycin + ceftriaxone, vancomycin + rifampicin and vancomycin + imipenem on the 2nd, 4th and 11th hospital days, respectively. She died on the 29th day with symptoms of sepsis. Necropsy and microscopic examination of the brain revealed localised inspissed layer of purulent exsudat over the convexities. Under this area the small wessels and capillaries were thrombotic and were surrounded by severe degeneration and necrosis in the white matter. RECOMMENDATIONS: Streptococcus pneumoniae has to be considered penicillin resistant until the organism is proved to be susceptible to penicillin. The authors advise the administration of dexamethasone, based on their own favourable 7 years experience.


Assuntos
Resistência Microbiana a Medicamentos , Meningite Pneumocócica/tratamento farmacológico , Meningite Pneumocócica/microbiologia , Streptococcus pneumoniae/classificação , Anti-Inflamatórios/uso terapêutico , Dexametasona/uso terapêutico , Evolução Fatal , Feminino , Humanos , Pessoa de Meia-Idade , Resistência às Penicilinas , Supuração , Falha de Tratamento
20.
Probl Khig ; 20: 59-68, 1995.
Artigo em Búlgaro | MEDLINE | ID: mdl-8524752

RESUMO

This study was concerned with the relationship of changes in cardiac variance to age. A total of 518 subjects were involved. The following indicators of ACV (analysis of cardiac variance) were investigated: mean--mean value of successive cardiac intervals, SD--standard deviation of mean value of cardiac intervals (R-R), AMo--amplitude of the mode, HI--homeostatic index, Pt--spectral power of R-R related to thermoregulation, Pr--spectral power of R-R related to respiration, IBO--index of centralization. For each one of these ACV indicators, a mathematical expression of its relationship to age was specified. The coefficients obtained from the indicated expressions of the relationship "age-to-ACV indicators" represent transfer coefficients for the particular measured quantities. Their methodological importance lies in the fact that through them it becomes possible to make age corrections of ACV indicator figures for the purpose of comparing individual subjects or groups of subjects. These coefficients help to establish nomograms for the particular age ranges.


Assuntos
Envelhecimento/fisiologia , Coração/fisiologia , Adulto , Eletrocardiografia/estatística & dados numéricos , Feminino , Frequência Cardíaca , Humanos , Masculino , Valores de Referência , Análise de Regressão , Processamento de Sinais Assistido por Computador
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