Assuntos
Antígenos Comuns de Leucócito/biossíntese , Células-Tronco Mesenquimais/metabolismo , Células Cultivadas , Metilases de Modificação do DNA/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Inibidores de Histona Desacetilases , Humanos , Antígenos Comuns de Leucócito/genética , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/patologiaAssuntos
Neoplasias Hematológicas/patologia , Células-Tronco Mesenquimais/citologia , Idoso , Idoso de 80 Anos ou mais , Antígenos CD/análise , Antígenos CD/metabolismo , Células da Medula Óssea , Técnicas de Cultura de Células , Células Cultivadas , Feminino , Neoplasias Hematológicas/terapia , Transplante de Células-Tronco Hematopoéticas , Humanos , Masculino , Pessoa de Meia-Idade , Transplante HomólogoRESUMO
The use of prophylactic antimicrobials during autologous peripheral blood stem cell transplantation (APBSCT) remains controversial. A prospective study was therefore conducted to examine whether the use of prophylactic antimicrobials is necessary. In this study, all the antimicrobials were given therapeutically rather than prophylactically. Twenty-three consecutive patients with heavily pretreated hematological malignancies were enrolled. All of the 23 patients had at least one episode of fever during APBSCT and most were fever of unknown origin (78.3%). Clinically or microbiologically documented infections occurred in only five patients (21.7%). These included bacteremias (three patients), perianal abscess (one patient), and catheter-related phlebitis (one patient). No death, invasive fungal infection, or serious adverse events occurred. The medium duration of fever, intravenous antimicrobial therapy, and hospital stay after transplantation were 5, 10, and 17 days, respectively. In conclusion, without using prophylactic antimicrobials, the infectious morbidity during APBSCT is low even in patients with heavily pretreated hematological malignancies.
Assuntos
Antibioticoprofilaxia , Neoplasias Hematológicas/complicações , Infecções/tratamento farmacológico , Transplante de Células-Tronco de Sangue Periférico/efeitos adversos , Adulto , Terapia Combinada , Febre/etiologia , Neoplasias Hematológicas/epidemiologia , Neoplasias Hematológicas/terapia , Humanos , Infecções/etiologia , Tempo de Internação , Pessoa de Meia-Idade , Morbidade , Estudos Prospectivos , Transplante Autólogo/efeitos adversosRESUMO
Pulsed laser ablation is a new method for deposition of thin layers of hydroxyapatite (HA) on to biomaterial surfaces. In this paper, we report activity and morphology of osteoblasts grown on HA surfaces fabricated using different laser conditions. Two sets of films were deposited from dense HA targets, at three different laser fluences: 3, 6 and 9 Jcm(-2). One set of the surfaces was annealed at 575 degrees C to increase the crystallinity of the deposited films. Primary human osteoblasts were seeded onto the material surfaces and cytoskeletal actin organisation was examined using confocal laser scanning microscopy. The annealed surfaces supported greater cell attachment and more defined cytoskeletal actin organisation. Cell activity, measured using the alamar Blue assay, was also found to be significantly higher on the annealed samples. In addition, our results show distinct trends that correlate with the laser fluence used for deposition. The cell activity increases with increasing fluence. This pattern was repeated for alkaline phosphatase production by the cells. Differences in cell spreading were apparent which were correlated with the fluence used to deposit the HA. The optimum surface for initial attachment and spreading of osteoblasts was one of the HA films deposited using 9 J cm(-2) laser fluence and subsequently annealed at 575 degrees C.
Assuntos
Divisão Celular , Durapatita , Osteoblastos/citologia , Titânio , Fosfatase Alcalina/metabolismo , Lasers , Osteoblastos/enzimologia , Fenótipo , Difração de Raios XRESUMO
The physical, chemical, and biological properties of pulsed laser deposited (PLD) and plasma sputtered (PS) hydroxyapatite (HA) coatings were compared. Human osteoblast-like cell responses to these coatings in vitro were assayed for proliferation and phenotypic expression. PS coatings formed smooth and continuous thin films that followed the contours of the substrate surface. PLD coatings consisted of numerous spheroidal micro- and macroparticles. The crystallinity of all coatings was quantified by comparison with the HA target used for both the PS and PLD processes. The XRD and FTIR results indicated that unannealed PLD coatings deposited at room temperature had X-ray spectra consistent with an amorphous structure and were found to dissolve after only a few hours in saline solution. Annealing at 400 degrees C increased the crystallinity (87-98%), which resulted in improved stability and cell activity. The PS coatings showed greater chemical stability than the unannealed PLD coatings and contained an approximate 15% crystalline phase, increasing to 65% postannealing. Cell proliferation and alkaline phosphatase production were significantly higher on unannealed PS specimens than the other coating treatments. There may be benefits in engineering the presence of a minor percentage of a microcrystalline phase in an amorphous or nanometer scale polycrystalline HA structure.
Assuntos
Ligas , Materiais Biocompatíveis , Durapatita , Osteoblastos/citologia , Osteoblastos/fisiologia , Titânio , Células Cultivadas , Humanos , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Difração de Raios XRESUMO
Several acoustic transmission and reflection technique measurements were carried out to determine mechanical properties (acoustic attenuation and velocity) versus frequency of polyvinylidene-fluoride (PVDF) and six other polymers. Acoustic measurements (0.5 to 12 MHz) included time-delay spectrometry (TDS; in which separate transmitting and receiving transducers utilize a swept frequency signal) and two pulse-echo methods (short tone burst echoes utilizing transducers with different center frequencies and Fourier analysis of echoes sent and received by damped transducers operating in the broadband pulse mode). Electrical impedance measurements of piezoelectric thin films of PVDF and P(VDF/TrFE) yielded comparable high frequency mechanical parameters. Of the seven acoustically examined polymers, PVDF had the greatest acoustic impedance, lowest acoustic velocity, and greatest mechanical loss (13.4 dB/cm per MHz). Polymethyl-methacrylate (PMMA; lucite) and polydimethyl-pentane (TPX) had the lowest loss. PMMA had the highest acoustic velocity, and TPX had the lowest acoustic impedance and a velocity almost identical to that of PVDF. These data are useful in the design of backing, matching, and lens materials to be used in association with PVDF transducers.
RESUMO
Plasma-sputtered hydroxyapatite (HA) thin coatings ( approximately 1 microm) were deposited onto uncoated and (TiAlV)N-coated Ti-6Al-4V-alloy substrates at low temperatures. The (TiAlV)N coating interlayer was deposited by reactive sputtering. Depositions were achieved by utilizing unbalanced and balanced magnetrons in a capacitively coupled RF plasma. Characterization of the thermostability, bioerosion resistance, and chemical composition of the coating layer was examined by scanning electron microscopy (SEM), energy-dispersive X-ray analysis (EDX), and Fourier transform infrared spectroscopy (FTIR). The results show that for deposition temperatures as low as 67 degrees C, the crystalline phase of the HA coating still is clearly detectable and that the underlying (TiAlV)N coating can increase the crystallinity and thermostability of the HA coating before and after heat treatment. The thin ( approximately 1 microm) sputtered HA coating shows strong HA characteristic peaks in the FTIR spectra even after a 30-day dissolution test. The experimental results show that a multilayer structure comprised of a bioinert (TiAlV)N and bioactive HA coating has the potential to improve the biocompatibility of implant materials. The bioinert (TiAlV)N coating also may provide a long-term stable interface between bone tissue and an alloy implant after the bioactive HA coating is remodeled by the surrounding tissue.
Assuntos
Ligas , Alumínio/química , Durapatita , Membranas Artificiais , Titânio/química , Vanádio/química , Cristalização , Teste de Materiais , Solubilidade , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de SuperfícieRESUMO
1. Intravenous infusion of capsazocaine (CAPBZ), a molecular fusion product of irritant synthetic capsaicin and local analgesic benzocaine, at 100 micrograms/kg/min for 15 min inhibited capsaicin (10 micrograms/kg, IV)-induced spinal release of substance P-like immunoreactivity and vagus reflex responses in blood pressure and heart rate changes in rats. 2. Intrathecal perfusion of CAPBZ (1.0 nM) also reversed retrograde epigastric intraarterial capsaicin (10 micrograms/kg)-induced hypotensive spinal reflex. 3. In isolated guinea pig tissues, CAPBZ (1.0-100.0 microM) inhibited capsaicin (1.0 microM)-sensitive sensory and functional activities, including cardiatonic, bronchial, tracheal and ileal contractilities. CAPBZ is suggested to be a capsaicin antagonist.
Assuntos
Benzoatos/farmacologia , Oxazóis/farmacologia , Receptores de Droga/antagonistas & inibidores , Células Receptoras Sensoriais/efeitos dos fármacos , Animais , Pressão Sanguínea/efeitos dos fármacos , Brônquios/efeitos dos fármacos , Peptídeo Relacionado com Gene de Calcitonina/farmacologia , Feminino , Cobaias , Frequência Cardíaca/efeitos dos fármacos , Íleo/efeitos dos fármacos , Técnicas In Vitro , Injeções Espinhais , Masculino , Contração Miocárdica/efeitos dos fármacos , Ratos , Ratos Wistar , Reflexo/efeitos dos fármacos , Medula Espinal/efeitos dos fármacos , Substância P/administração & dosagem , Substância P/farmacologia , Traqueia/efeitos dos fármacos , Nervo Vago/efeitos dos fármacosRESUMO
It has been shown that nitric-oxide (NO) was synthesized in the central nervous system as well as in vascular endothelial cells. We reported recently that nitric oxide was involved in central cardiovascular regulation of rat brainstem nuclei. In the present study, we evaluated further the baroreflex response of NO in the nucleus tractus solitarii (NTS) of rats. Male Sprague-Dawley rats were anesthetized with urethane, blood pressure and heart rate was monitored intra-arterially. Intramedullary microinjection (60 nl) of NO synthase inhibitor NG-methyl-L-arginine (L-NMMA), NG-nitro-L-arginine methyl ester(L-NAME) or normal saline was made into the NTS. Baroreflex response were elicited by increasing doses of phenylephrine (10-30 micrograms/Kg i.v.) before and after intra-NTS administration of L-NMMA, L-NAME or normal saline. The reflex bradycardia elicited by phenylephrine was significantly inhibited by the pretreatment of L-NMMA or L-NAME. Furthermore, the inhibitory effects on baroreflex activation by L-NMMA were significantly reversed by pretreatment with L-arginine. These results suggested that central endogenous NO was involved in the medullary regulation of blood pressure and that NO synthase inhibitor attenuated baroreflex activation.
Assuntos
Barorreflexo/efeitos dos fármacos , Tronco Encefálico/efeitos dos fármacos , Óxido Nítrico/fisiologia , Animais , Masculino , Fenilefrina/farmacologia , Ratos , Ratos Sprague-Dawley , ômega-N-Metilarginina/farmacologiaRESUMO
One hundred and ninety seven strains of Pseudomonas aeruginosa were isolated from urine (59 strains), wound pus (60 strains), sputum (30 strains), stool (30 strains) and eye discharge (18 strains) at Kaohsiung medical College Hospital. These strains were serotyped with antisera against O antigens and tested with twelve different antimicrobial agents. The results showed that the most frequently isolated strains were serotype E (41.1%), followed by serotype B (20.3%), serotype F (10.7%) and serotype L (9.1%). In in vitro susceptibility testing, all isolated strains were resistant to chloramphenicol and tetracycline. Otherwise, these isolates were highly susceptible to ceftazidime (95.4%), enoxacin (89.3%) and piperacillin (87.8%). The isolates from urine exhibited more multiple drug resistance patterns than those of other specimens. When plasmid content was analysed from pseudomonas aeruginosa, only 15.2% (30/197) of isolates carried plasmids. By conjugation, transformation and mobilization experiments, it was shown that 13.3% (4/30) of plasmid carrying strains contained R plasmids.
Assuntos
Plasmídeos/análise , Pseudomonas aeruginosa/efeitos dos fármacos , Cloranfenicol/farmacologia , Resistência Microbiana a Medicamentos/genética , Humanos , Pseudomonas aeruginosa/genética , Fatores R/análise , Tetraciclina/farmacologiaRESUMO
We describe here an improved procedure for polymerase chain reaction (PCR)-based single strand conformation polymorphism (SSCP) for rapid mutational detection. To circumvent the restriction of having to analyze relatively short PCR fragments, restriction endonucleases were used to cleave a longer PCR product and the mixture of fragments was analyzed directly in SSCP gel electrophoresis. This multiple restriction fragment (MRF)-SSCP protocol was demonstrated by the detection of a 4-bp deletion in codons 41-42 and a point mutation in the IVS-2 sequence of the human beta-globin gene. The MRF-SSCP or the standard SSCP protocol was then combined with the linear amplification DNA sequencing (LADS) procedure for direct analysis of the PCR products without further purification for an exact characterization of the mutations detected. In the LADS analysis, homo- or heterozygosity of a mutation was easily distinguished by the appearance of a single- or double-lane band in the sequencing gel. The choice of isotope used and different labeling methods were compared and were found, in some cases, to produce SSCP patterns of different complexities. The combined MRF-SSCP/LADS protocol permits rapid mutational analysis of a large number of clinical samples using only very small amounts of materials and can easily be adopted for nonisotopic clinical applications.