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1.
Microb Ecol ; 76(1): 9-18, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26879941

RESUMO

The microbial ecology of various natural environments has been an active area of research since the earlier part of the twentieth century. Remote and sometimes extreme environments such as the deep ocean and the deep terrestrial subsurface have revealed a remarkable array of microorganisms. The majority of these environments are nutrient limited, and microorganisms-principally, bacteria-have developed a number of survival strategies that enable their survival and, in some cases, replication. While planktonic microorganisms exist in oligotrophic environments, the predominant mode of survival and growth is associated with biofilms. There are a number of similarities between the physicochemistry of industrial water systems and some natural aquatic ecosystems, and these similarities extend to the microbial populations and the survival mechanisms that are employed. The "starvation-survival" mechanisms, including biofilm formation, may be associated with deleterious effects on industrial water systems. These effects include heat transfer inhibition, microbially influenced corrosion, and contamination of various products manufactured in a wide array of industries. Biological fouling of industrial water systems has significant direct and indirect (through antimicrobial chemical applications) impacts on engineered materials and on the etiology of some waterborne diseases. This review provides an overview of the microbial ecology of purified waters and discusses the impacts of biological activity on industrial systems.


Assuntos
Fenômenos Fisiológicos Bacterianos , Ecologia , Água Doce/microbiologia , Microbiologia Industrial , Microbiologia da Água , Bactérias/citologia , Bactérias/crescimento & desenvolvimento , Biofilmes/crescimento & desenvolvimento , Corrosão , Atenção à Saúde , Eletroquímica , Meio Ambiente , Ambientes Extremos , Hospitais , Resíduos Industriais , Centrais Nucleares , Nutrientes , Semicondutores , Bactérias Redutoras de Enxofre , Doenças Transmitidas pela Água
2.
J Intern Med ; 281(3): 284-299, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27926979

RESUMO

BACKGROUND: The EUMDS registry is an unique prospective, longitudinal observational registry enrolling newly diagnosed patients with lower-risk myelodysplastic syndrome (MDS) from 17 European countries from both university hospitals and smaller regional hospitals. OBJECTIVE: The aim of this study was to describe the usage and clinical impact of erythropoiesis-stimulating agents (ESAs) in 1696 patients enrolled between 2008 and 2014. METHODS: The effects of ESAs on outcomes were assessed using proportional hazards models weighting observations by propensity to receive ESA treatment within a subset of anaemic patients with or without a regular transfusion need. RESULTS: ESA treatment (median duration of 27.5 months, range 0-77 months) was administered to 773 patients (45.6%). Outcomes were assessed in 897 patients (484 ESA treated and 413 untreated). ESA treatment was associated with a nonsignificant survival benefit (HR 0.82, 95% CI: 0.65-1.04, P = 0.09); this benefit was larger amongst patients without prior transfusions (P = 0.07). Amongst 539 patients for whom response to ESA treatment could be defined, median time to first post-ESA treatment transfusion was 6.1 months (IQR: 4.3-15.9 months) in those transfused before ESA treatment compared to 23.3 months (IQR: 7.0-47.8 months) in patients without prior transfusions (HR 2.4, 95% CI: 1.7-3.3, P < 0.0001). Responding patients had a better prognosis in terms of a lower risk of death (HR 0.65, 95% CI: 0.45-0.893, P = 0.018), whereas there was no significant effect on the risk of progression to acute myeloid leukaemia (HR 0.71, 95% CI: 0.39-1.29, P = 0.27). CONCLUSION: Appropriate use of ESAs can significantly delay the onset of a regular transfusion need in patients with lower-risk MDS.


Assuntos
Transfusão de Sangue , Hematínicos/uso terapêutico , Síndromes Mielodisplásicas/terapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Progressão da Doença , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/mortalidade , Estudos Prospectivos , Fatores de Risco , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
4.
Int J Geriatr Psychiatry ; 25(7): 725-31, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19823985

RESUMO

BACKGROUND: Understanding the underlying mechanisms and risk factors leading to agitation is crucial to reduce the severity of agitation and increase quality of life. International comparative studies offer special advantages in elucidating environmental risk factors by providing a wider diversity of environmental exposures such as nursing home structures, health care systems and genetic diversity. METHODS: Baseline data for three different intervention studies in Austria (n = 38), England (n = 302) and Norway (n = 163) were combined posthoc. Patients were grouped according to their dementia severity using the global deterioration scale (GDS), functional assessment staging (FAST) and clinical dementia rating (CDR) scales. For the measurement of agitation, the Cohen-Mansfield Agitation Inventory (CMAI) was used. Data analysis was performed using one-way ANOVA, multivariate and linear regression analysis. RESULTS: CMAI scores were available for 503 subjects with dementia. There were significant differences between the nursing home residents in the three countries regarding age, gender and dementia severity (all p values < 0.001). In the multivariate analyses, the level of agitation differed with higher mean scores in the Austrian (mean (SD) score 51.9(21.8)) compared to UK (43.3(16.1)) and Norwegian (41.6(13.2)) nursing homes (p = 0.002). Similarly, the use of psychotropic drugs differed significantly, with a higher proportion of neuroleptics in UK (48%, p < 0.001) and Austrian (52.6%; p = 0.001) compared to Norwegian (19%) nursing homes. CONCLUSION: We found differences in agitation and antipsychotic drug use which are likely related to structural and cultural differences in nursing homes in three European countries. These findings suggest that structural changes can improve quality of care and quality of life for nursing home residents.


Assuntos
Instituição de Longa Permanência para Idosos/organização & administração , Casas de Saúde/organização & administração , Agitação Psicomotora/tratamento farmacológico , Agitação Psicomotora/epidemiologia , Psicotrópicos/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Áustria/epidemiologia , Inglaterra/epidemiologia , Feminino , Avaliação Geriátrica , Instituição de Longa Permanência para Idosos/estatística & dados numéricos , Humanos , Masculino , Testes Neuropsicológicos , Noruega/epidemiologia , Casas de Saúde/estatística & dados numéricos , Projetos Piloto , Agitação Psicomotora/diagnóstico , Qualidade de Vida , Índice de Gravidade de Doença
5.
Gene ; 110(2): 197-203, 1992 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-1537556

RESUMO

To clarify the molecular mechanisms involved in the developmental control of hemoglobin-encoding genes we have been studying the expression of these genes in human cells in continuous culture. We have previously reported the presence of a transcriptional control element with the properties of a silencer extending from -392 to -177 bp relative to the cap site of the human epsilon-globin-encoding gene [Cao et al., Proc. Natl. Acad. Sci. USA 86 (1989) 5306-5309]. We also showed that this silencer has stronger inhibitory activity in HeLa cells, as compared to K562 human erythroleukemia cells. Using deletion mutants and cis-cloned synthetic oligodeoxyribonucleotides in transient expression assays, nucleotide sequences responsible for this effect have now been further delimited to 44 bp located from -294 to -251 bp. Gel electrophoresis mobility shift assays and DNaseI footprinting assays demonstrate that these negative regulatory sequences are recognized differently by proteins present in nuclear extracts obtained from HeLa and K562 cells. Two binding proteins are detected in K562 nuclear extracts, while only one is found in extracts from HeLa cells. Possible mechanisms by which these proteins may regulate transcription of the epsilon-globin-encoding gene in erythroid and non-erythroid cells are discussed.


Assuntos
Eritrócitos/química , Regulação da Expressão Gênica/fisiologia , Globinas/genética , Oligodesoxirribonucleotídeos/metabolismo , Sequências Reguladoras de Ácido Nucleico/fisiologia , Transativadores/metabolismo , Sequência de Bases , Cloranfenicol O-Acetiltransferase/genética , Cloranfenicol O-Acetiltransferase/metabolismo , DNA Recombinante/genética , DNA Recombinante/metabolismo , Desoxirribonuclease I/metabolismo , Eletroforese , Células HeLa , Humanos , Leucemia Eritroblástica Aguda , Dados de Sequência Molecular , Oligodesoxirribonucleotídeos/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Sequências Reguladoras de Ácido Nucleico/genética , Transativadores/genética , Transativadores/fisiologia , Células Tumorais Cultivadas
6.
Neurology ; 47(3): 810-3, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8797485

RESUMO

Hippocampal formation (HF) atrophy, although common in normal aging, has unknown clinical consequences. We used MRI to derive HF size measurements at baseline on 44 cognitively normal older adults entering a longitudinal study of memory function (mean age = 68.4 years, mean follow-up = 3.8 years). Only one subject became demented at follow-up. Multiple regression analyses controlling for age, gender, education, and diffuse cerebral atrophy revealed that HF size significantly predicted longitudinal change on memory tests previously found sensitive to decline in normal aging. These results indicate HF atrophy may be a risk factor for accelerated memory dysfunction in normal aging.


Assuntos
Envelhecimento/fisiologia , Hipocampo/anatomia & histologia , Memória/fisiologia , Idoso , Feminino , Hipocampo/fisiologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Valores de Referência
7.
Leuk Res ; 11(3): 215-22, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3031385

RESUMO

The presence of potential murine leukemia and overt leukemia cells in various organs at different phases of leukemogenesis was demonstrated by transplantation experiments and sensitivity to bacteriocin (colicin HSC10). Such correlation was found in three experimental models: AKR mice developing spontaneous T-cell leukemia and BL/6 mice infected with radiation leukemia virus variants inducing a high or low overt T-cell leukemia incidence. The sensitivity to bacteriocin was evaluated by testing the cell cycle perturbation following in-vitro incubation of lymphoid cells with colicin (or Tris buffer as controls) monitored by flow-cytometry. The analysis was based on measuring relative differences in fluorescence intensity of propidium iodide stained DNA in the individual cells. The interaction with colicin of leukemic cells and lymphoid cells containing potential leukemic cells (PLC) resulted in a reduction in the cell number of the G0/G1 and SG2M phases while cells accumulated in the "pre-G1" channels. In contrast, normal lymphoid cells exposed to bacteriocin did not show such changes in the DNA histograms. The distribution pattern of PLC in the thymus and spleen (in the models tested) obtained by transplantation studies coincided with sensitivity of spleen and thymus cells to colicin. However, in most instances, the PLC in the bone marrow were not recognized by colicin, but their leukemogenic potential was reduced following interaction with colicin as shown by PLC transplantation studies. It is thus suggested that colicin might be used for identification and eradication of transformed cells.


Assuntos
Bacteriocinas/farmacologia , Leucemia Experimental/tratamento farmacológico , Fatores Etários , Animais , Medula Óssea/patologia , Ciclo Celular/efeitos dos fármacos , Transformação Celular Neoplásica/efeitos dos fármacos , DNA/análise , Vírus da Leucemia Murina , Leucemia Experimental/patologia , Camundongos , Camundongos Endogâmicos , Transplante de Neoplasias , Baço/patologia , Linfócitos T , Timo/patologia
8.
Leuk Res ; 20(6): 459-66, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8709617

RESUMO

The human erythropoietin receptor (EpoR) gene has been cloned and characterized. Very few EpoR genetic abnormalities have been reported so far. Polycythemia vera (PV) is characterized by low/normal serum erythropoietin (Epo) levels with proposed Epo hypersensitivity. Myelodysplastic syndromes (MDS) are characterized by refractory anemia with variable serum Epo levels. Several reports have suggested EpoR abnormalities in both types of stem cell disorders. We analyzed DNA obtained from peripheral blood mononuclear cells of seven healthy controls, 20 patients with myeloproliferative disorders (MPD, 11 patients with PV, five agnogenic myeloid metaplasia with myelofibrosis, four essential thrombocytosis) and eight patients with refractory anemia with ringed sideroblasts (RARS), an MDS variant. The DNA was digested with four restriction enzymes (BamHI, Bgl II, Sacl and HindIII), followed by Southern blot, using a 32P radiolabeled probe, containing 1.5 kb of the human EpoR cDNA. All 20 MPD patients and seven out of the eight MDS patients demonstrated a restriction pattern which was identical to the seven normal controls, as well as to the erythroid cell line K562, and also consistent with the expected restriction map, for all four enzymes tested. One RARS patient had a normal pattern with three enzymes but a different one with HindIII. The HindIII 12 kb large band was replaced by a faint 12 kb band and a new (about 9 kb) band appeared. The EpoR restriction map and the normal pattern obtained with the other three enzymes suggest that this patient has a 3 kb upstream deletion in one allelic EpoR gene. The same molecular pattern was detected in the patient's sister, who suffers from anemia with mild bone marrow (BM) dyserythropoiesis and plasmacytosis. Northern blot analysis showed that the patient's BM RNA carried normal EpoR message. This familial pattern may represent polymorphism. However, the patient's very high serum Epo level, her resistance to treatment with recombinant Epo, and the abnormally low growth rate of in vitro erythroid cultures, suggesting poor response to Epo in this MDS patient as well as the hematological abnormalities in her sister, support the speculation that the different EpoR gene might serve as a genetic predisposing marker and potentially could be involved (probably via post-transcriptional mechanisms and by an interaction with other factors or cytokines) in the pathogenesis. Our data suggest that the EpoR is intact in MPD and in most patients with RARS. One RARS patient had a familial different genetic structure, which could represent polymorphism. However, we can speculate also that it might be involved in the pathogenesis of the disease.


Assuntos
Síndromes Mielodisplásicas/genética , Transtornos Mieloproliferativos/genética , Receptores da Eritropoetina/genética , Idoso , Northern Blotting , DNA/sangue , DNA de Neoplasias/sangue , Células Precursoras Eritroides/efeitos dos fármacos , Eritropoetina/sangue , Eritropoetina/farmacologia , Saúde da Família , Feminino , Humanos , Leucemia Eritroblástica Aguda/metabolismo , Masculino , Síndromes Mielodisplásicas/sangue , Transtornos Mieloproliferativos/sangue , Prognóstico , RNA/análise , Células Tumorais Cultivadas
9.
Shock ; 4(5): 373-8, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8595526

RESUMO

The bactericidal effect of free versus liposomal cefoxitin was evaluated in the major reticuloendothelial organs in a porcine model of intra-abdominal sepsis. Yorkshire Landrace pigs were inoculated with 3.2 x 10(10) (n = 5) or 1.4 x 10(11) (n = 7) cfu of Escherichia coli mixed in sterile feces/animal. Two treatment groups inoculated with 1.4 x 10(11) cfu were established: free cefoxitin (n = 9) and liposomal cefoxitin (n = 9). All animals were maintained under anesthesia and euthanized after 24 h. The number of E. coli recovered in the liver, lungs, and spleen was significantly affected by inoculum size (p < .05). The liver had significantly higher numbers of bacteria (p < .05) compared with the other organs, regardless of the inoculum size. The liver and the lung of the liposomal cefoxitin-treated group showed significantly lower numbers of E. coli (5.0 x 10(4) and 6.3 x 10(2), respectively) compared with the untreated (liver, 6.3 x 10(7); lung, 2.0 x 10(6)) and free cefoxitin (liver, 5.0 x 10(6); lung, 7.9 x 10(4))-treated groups (p < .05). At 2 h following the injection of free and liposomal cefoxitin, the decrease of E. coli in peritoneal fluid compared with the nontreated septic group was significant (p < .05). No growth was observed from blood cultures taken 24 h after sepsis induction. All control experiments yielded negative cultures. The results of these experiments demonstrated that liposomal cefoxitin exerts an enhanced bactericidal effect in liver and lungs during Gram-negative sepsis.


Assuntos
Cefoxitina/farmacologia , Cefamicinas/farmacologia , Escherichia coli/efeitos dos fármacos , Sepse/tratamento farmacológico , Análise de Variância , Animais , Cefoxitina/administração & dosagem , Cefamicinas/administração & dosagem , Modelos Animais de Doenças , Escherichia coli/isolamento & purificação , Lipossomos , Masculino , Sepse/microbiologia , Suínos
10.
Shock ; 6 Suppl 1: S43-9, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8828097

RESUMO

The effects of free versus liposomal cefoxitin on various physiological parameters in a porcine model of Gram-negative intra-abdominal sepsis were evaluated. Four different doses of Escherichia coli inoculum mixed with sterile pig feces were used (10(8), 10(9), 10(10), and 10(11) cfu/animal), and the most consistent hemodynamic changes were observed with an inoculum of approximately 10(11) bacteria/20 kg animal. Two treatment groups were established as follows: free cefoxitin (n = 9) and liposomal cefoxitin (n = 9). All animals were maintained under anesthesia for the duration of the study, and then euthanized 24 h following intra-abdominal inoculation. The inoculated and nontreated animals showed increases in heart rate, mean pulmonary arterial pressure, systemic and pulmonary vascular resistance, and decreases in mean systemic arterial pressure and cardiac index. These changes were significant (p < .05) compared with a control group injected with normal saline. Liposomal cefoxitin-treated animals showed significantly lower decreases in mean systemic arterial pressure and increases in heart rate (p < .05) compared with both the inoculated nontreated and free cefoxitin-treated groups. Both liposomal and free cefoxitin significantly modulated the mean pulmonary arterial pressure compared with the inoculated nontreated animals (p < .05). Acidosis that developed during intra-abdominal infection diminished 6 h following the first dose of liposomal cefoxitin (p < .05). The results of these experiments demonstrate that liposomal cefoxitin exerts a beneficial modulation of some of the hemodynamic disturbances during intra-abdominal Gram-negative sepsis.


Assuntos
Bacteriemia/tratamento farmacológico , Cefoxitina/farmacologia , Infecções por Escherichia coli/tratamento farmacológico , Hemodinâmica/efeitos dos fármacos , Abdome , Animais , Bacteriemia/fisiopatologia , Pressão Sanguínea/efeitos dos fármacos , Débito Cardíaco/efeitos dos fármacos , Cefoxitina/administração & dosagem , Cefoxitina/uso terapêutico , Portadores de Fármacos , Infecções por Escherichia coli/fisiopatologia , Frequência Cardíaca/efeitos dos fármacos , Lipossomos , Masculino , Suínos , Resistência Vascular/efeitos dos fármacos
11.
Chest ; 104(6): 1698-701, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8252945

RESUMO

We studied the effect of external high-frequency oscillation using an oscillator (Hayek oscillator [HO]) on 20 patients with severe chronic obstructive pulmonary disease (COPD). Of the 20 patients, 10 were eucapnic and 10 were hypercapnic. The HO generated frequencies from 60 to 140 cycles/min at an amplitude of 36 cm H2O (-26 to +10) and at an inspiratory/expiratory (I/E) ratio of 1:1. The results show that the HO is a powerful ventilator, reducing end-tidal PCO2 (PETCO2) by 6.7 to 9.1 mm Hg in eucapnic patients and by 6.1 to 7.9 mm Hg in hypercapnic patients. The oxygen saturation increased by 2 to 2.87 percent in the eucapnic patients and by 2.6 to 3.7 percent in the hypercapnic group in the various frequencies. The rate of elimination of CO2 and the levels of PETCO2 achieved within a short time were superior to those reported with other external ventilators. We conclude that the HO can be effectively used in severe COPD and respiratory failure for (1) assisting ventilation, thus replacing intubation and conventional mechanical ventilation, and (2) relieving muscle fatigue in short sessions.


Assuntos
Ventilação de Alta Frequência , Pneumopatias Obstrutivas/terapia , Idoso , Humanos , Pneumopatias Obstrutivas/fisiopatologia , Troca Gasosa Pulmonar
12.
Chest ; 83(1): 143-4, 1983 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-6401239

RESUMO

Complications of subclavian vein catheterization are common and include pneumothorax, hemothorax, and sepsis. Osteomyelitis is a rare complication. The present report describes a patient with osteomyelitis of both clavicles due to subclavian vein venipuncture, in whom fever and chills were absent and the sole clinical finding was local pain and tenderness in the involved area.


Assuntos
Cateterismo/efeitos adversos , Clavícula , Osteomielite/etiologia , Infecções por Pseudomonas/etiologia , Veia Subclávia , Idoso , Clavícula/diagnóstico por imagem , Feminino , Humanos , Pseudomonas aeruginosa , Radiografia
13.
Biomaterials ; 21(12): 1235-46, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10811305

RESUMO

Bacterial infection is a frequent complication associated with the use of medical devices. In an effort to address this problem, antibacterial agents have been incorporated or applied directly onto the surfaces of numerous types of medical devices. This study assessed the feasibility of using a novel biodegradable polymer to release antibiotic drugs in response to inflammatory related enzymes. A model drug polymer was synthesized using 1,6-hexane diisocyanate (HDI), polycaprolactone diol (PCL), and a fluoroquinolone antibiotic, ciprofloxacin. Polymers were characterized by size-exclusion chromatography (SEC), and elemental analysis. Biodegradation studies were carried out by incubating the polymers with solutions of cholesterol esterase (CE) or phosphate buffer (pH 7.0) for 30 days at 37 degrees C. The degradation was assessed by high-performance liquid chromatography (HPLC), mass spectrometry (MS) and 14C radiolabel release. Subsequently, the activity of the released antibiotic was assessed against a clinical isolate of Pseudomonas aeruginosa. HPLC analysis showed the release of multiple degradation products which were identified, by tandem MS, to include ciprofloxacin and derivatives of ciprofloxacin. The microbiological assessment showed that the released ciprofloxacin possessed antimicrobial activity; 1 microg/ml was measured after 10 days. The results of this study suggest that these novel bioresponsive antimicrobial polymers or similar analogs show promise for use in the control of medical device associated infections.


Assuntos
Implantes Absorvíveis , Materiais Biocompatíveis/síntese química , Ciprofloxacina/análogos & derivados , Ciprofloxacina/administração & dosagem , Poliésteres/síntese química , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Ciprofloxacina/síntese química , Ciprofloxacina/química , Ciprofloxacina/farmacocinética , Ciprofloxacina/farmacologia , Preparações de Ação Retardada , Difusão , Portadores de Fármacos , Estudos de Viabilidade , Espectrometria de Massas , Teste de Materiais , Testes de Sensibilidade Microbiana , Peso Molecular , Poliésteres/química , Pseudomonas aeruginosa/efeitos dos fármacos , Esterol Esterase/metabolismo
14.
Biomaterials ; 19(4-5): 327-39, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9677148

RESUMO

Biomaterial-centred infections are often difficult to treat. An impaired immune response, acute inflammatory reactions and the presence of recalcitrant attached microorganisms are all contributing factors. A brief review of the role of attached bacteria in biomaterial-centred infections is presented. Two major hypotheses which may explain the recalcitrance of biofilms to antimicrobial agents are discussed. The analytical capabilities of attenuated total reflection Fourier transform infrared (ATR/FTIR) spectroscopy for providing information on both transport of an antimicrobial agent to bacteria embedded in the biofilm and interactions between an antimicrobial agent and biofilm components are described.


Assuntos
Bactérias , Aderência Bacteriana , Infecções Bacterianas/etiologia , Materiais Biocompatíveis , Biofilmes , Infecções Bacterianas/prevenção & controle , Materiais Biocompatíveis/efeitos adversos , Humanos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos
15.
Biomaterials ; 19(20): 1877-84, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9855189

RESUMO

The adhesion of bacteria to medical implants and the subsequent development of a biofilm frequently results in the infection of surrounding tissue and may require removal of the device. We have developed a liposomal hydrogel system that significantly reduces bacterial adhesion to silicone catheter material. The system consists of a poly (ethylene glycol)-gelatin hydrogel in which liposomes containing the antibiotic ciprofloxacin are sequestered. A poly (ethylene glycol)-gelatin-liposome mixture was applied to a silicone surface that had been pre-treated with phenylazido-modified gelatin. Hydrogel cross-linking and attachment to surface-immobilized gelatin was accomplished through the formation of urethane bonds between gelatin and nitrophenyl carbonate-activated poly (ethylene glycol). Liposomal hydrogel-coated catheters were shown to have an initial ciprofloxacin content of 185+/-16 microg cm(-2). Ciprofloxacin was released over seven days with an average release rate of 1.9+/-0.2 microg cm(-2) h(-1) for the first 94 h. In vitro assays using a clinical isolate of Pseudomonas aeruginosa established the antimicrobial efficacy of the liposomal hydrogel. A modified Kirby-Bauer assay produced growth-inhibition zone diameters of 39+/-1 mm, while bacterial adhesion was completely inhibited on catheter surfaces throughout a seven-day in vitro adhesion assay. This new antimicrobial coating shows promise as a prophylactic and/or treatment for catheter-related infection.


Assuntos
Anti-Infecciosos/administração & dosagem , Aderência Bacteriana , Infecções Bacterianas/prevenção & controle , Materiais Biocompatíveis/administração & dosagem , Cateterismo , Ciprofloxacina/administração & dosagem , Hidrogéis/administração & dosagem , Biofilmes , Lipossomos , Polietilenoglicóis , Infecções por Pseudomonas/prevenção & controle , Pseudomonas aeruginosa , Silicones , Raios Ultravioleta
16.
J Am Geriatr Soc ; 44(2): 144-50, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8576503

RESUMO

OBJECTIVE: To examine the anticipated decisions to consent to or to forgo life-sustaining treatment by spouses of patients with Alzheimer's disease and to describe the relationship of spouse and patient characteristics to predicted decisions. DESIGN: Prospective quantitative study. SETTING: The Aging and Dementia Research Center (ADRC), part of an Alzheimer's Disease Center Core Grant, at New York University Medical Center. PARTICIPANTS: Fifty spouse caregivers of Alzheimer's disease patients, evaluated at the ADRC, who had a minimum Stage 4 on the Global Deterioration Scale. MEASUREMENTS: Spouses were presented with two conditions (critical illness and irreversible coma) and rated their agreement with, certainty of, and comfort with four treatments (resuscitation, breathing machine, feeding tube, and antibiotics). Data were also obtained as to patients' current quality of life, spouses' standard of decision-making, and spouse burden. RESULTS: Eighteen of 50 patients had a durable power of attorney for health care, 20 of 50 had a living will, and 26 of 50 had neither. In the face of critical illness, almost equal numbers of spouses would consent to or forgo CPR, 28 of 50 would forgo a breathing machine, 21 of 50 a would forgo a feeding tube, and 5 of 50 would forgo antibiotics. Five of 50 would forgo all four treatments, and 12 of 50 all but antibiotics. Spouses were significantly more likely to forgo treatment in the face of coma than for critical illness (P < .001). Spouses were more certain about decisions related to coma than to critical illness (P < .001), and there was a positive and significant correlation between certainty and comfort (P = .001). Those consenting to treatment were more comfortable than those forgoing treatment (for CPR and antibiotics P = .001). Spouses of patients with Stage 7 AD were more likely to forgo CPR than those with Stages 4 to 6 AD (P < .001). Only two of 50 spouses selected descriptors congruent with a purely substituted judgment standard of decision-making. An equal number of spouses rated patient quality of life as good, fair, or poor. For critical illness, the poorer the quality of life rating, the more likely the spouses were to forgo feeding tubes (P < .001). There was a trend for highly burdened spouses to consent to treatment. CONCLUSIONS: The results provide evidence that spouses of patients with AD anticipate forgoing life-sustaining treatments in the face of coma but are less sure about choices for critical illness. Although preliminary in nature, findings suggest that doctors, nurses, and social workers need to provide additional support to spouses choosing to forgo rather than consent to treatment and need to inquire as to what spouses perceive as the factors that are important to them in making a decision.


Assuntos
Doença de Alzheimer/terapia , Tomada de Decisões , Cuidados para Prolongar a Vida , Defesa do Paciente , Cônjuges/psicologia , Suspensão de Tratamento , Diretivas Antecipadas , Idoso , Coma/terapia , Estado Terminal/terapia , Estudos Transversais , Feminino , Serviços de Assistência Domiciliar , Humanos , Masculino , Estudos Prospectivos , Ordens quanto à Conduta (Ética Médica) , Inquéritos e Questionários , Incerteza
17.
J Cancer Res Clin Oncol ; 108(3): 351-3, 1984.
Artigo em Inglês | MEDLINE | ID: mdl-6511809

RESUMO

A patient with malignant lymphoma showed severe hypophosphatemia during a blastic crisis. x-Ray microprobe analysis of the cells at this stage revealed a high phosphorus content. Following treatment and a decline in the white cell count the serum phosphorus increased, whereas the cellular phosphorus decreased. The potential prognostic value of serum and cellular phosphorus determinations during the course of malignant disorders of the hematopoietic system is discussed.


Assuntos
Ativação Linfocitária , Linfoma/sangue , Fósforo/sangue , Adulto , Terapia Combinada , Microanálise por Sonda Eletrônica , Humanos , Linfócitos/metabolismo , Linfoma/terapia , Masculino
18.
FEMS Microbiol Lett ; 119(3): 303-8, 1994 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-7519575

RESUMO

Twenty-five isolates of dissimilatory sulfate-reducing bacteria were clustered based on similarity analysis of their phospholipid ester-linked fatty acids (PLFA). Of these, 22 showed that phylogenetic relationships based on the sequence similarity of their 16S rRNA directly paralleled the PLFA relationships. Desulfobacter latus and Desulfobacter curvatus grouped with the other Desulfobacter spp. by 16S rRNA comparison but not with the PLFA analysis as they contained significantly more monoenoic PLFA than the others. Similarly, Desulfovibrio africanus clustered with the Desulfovibrio spp. by 16S rRNA but not with them when analyzed by PLFA patterns because of higher monoenoic PLFA content. Otherwise, clustering obtained with either analysis was essentially congruent. The relationships defined by PLFA patterns appeared robust to shifts in nutrients and terminal electron acceptors. Additional analyses utilizing the lipopolysaccharide-lipid A hydroxy fatty acid patterns appeared not to shift the relationships based on PLFA significantly except when completely absent, as in Gram-positive bacteria. Phylogenetic relationships between isolates defined by 16S rRNA sequence divergence represent a selection clearly different from the multi-enzyme activities responsible for the PLFA patterns. Determination of bacterial relationships based on different selective pressures for various cellular components provides more clues to evolutionary history leading to a more rational nomenclature.


Assuntos
Desulfovibrio/genética , Ácidos Graxos/química , Fosfolipídeos/química , Filogenia , RNA Ribossômico 16S/genética , Desulfovibrio/química , Ácidos Graxos/análise , Família Multigênica , Fosfolipídeos/análise , RNA Bacteriano/química , RNA Bacteriano/genética , RNA Ribossômico 16S/química , Análise de Sequência de RNA , Microbiologia da Água
19.
Int J Hematol ; 71(2): 95-8, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10745619

RESUMO

Bleeding in myelodysplastic syndromes (MDS) is often related to thrombocytopenia. However, because MDS is a stem cell disorder, it is conceivable that platelet function (PF) abnormalities may play a role as well. A few studies have been reported, mainly with platelet aggregation (PA). A summary of the information discloses that about 68 MDS patients have been studied. Despite some conflicting data, it can be concluded that PA defects are quite common in MDS. About 75% of MDS patients demonstrated reduced PA with epinephrine, followed by decreased PA with arachidonic acid (54%), ADP (46%), collagen (43%), and ristocetin (22%). Several other PFs were studied, but the data require caution in interpretation. Despite the relatively high incidence of platelet dysfunction, bleeding in MDS patients is uncommon, with episodes tending to be mild, although recurrent. Nevertheless, some correlation between PA abnormalities and the tendency to bleed has been suggested. As patients demonstrate more PA defects, they tend to bleed more. Some authors suggest that PF studies may assist in diagnosing tough cases of MDS, as well as serving as prognostic markers. A large-scale study testing PF in a large number of MDS patients is required and is expected.


Assuntos
Síndromes Mielodisplásicas/sangue , Ativação Plaquetária , Transtornos da Coagulação Sanguínea , Plaquetas/patologia , Humanos , Síndromes Mielodisplásicas/patologia , Síndromes Mielodisplásicas/fisiopatologia
20.
Int J Hematol ; 71(2): 184-7, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10745630

RESUMO

Neurological complications in thrombotic thrombocytopenic purpura (TTP) are associated with poor prognosis and/or permanent damage. We report a young woman in whom the diagnosis of TTP was difficult because cardinal manifestations were absent at presentation. The patient relapsed, showing severe and dramatic neurological manifestations, including coma. She was treated with multiple therapeutic modalities and recovered fully with no neurological sequelae. The difficulties involved in the management of chronic relapsing TTP are discussed. In the absence of clear guidelines, patients are still subjected to different treatment modalities according to the personal opinions and approaches of physicians. Clearly, well-controlled clinical trials to address this problem are required.


Assuntos
Púrpura Trombocitopênica Trombótica/terapia , Adulto , Antineoplásicos/uso terapêutico , Doença Crônica , Coma/etiologia , Terapia Combinada , Intervalo Livre de Doença , Feminino , Humanos , Doenças do Sistema Nervoso/etiologia , Plasmaferese , Púrpura Trombocitopênica Trombótica/complicações , Púrpura Trombocitopênica Trombótica/diagnóstico , Resultado do Tratamento
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