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1.
J Vet Pharmacol Ther ; 41(3): 476-484, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29465161

RESUMO

Parasitic diseases have a significant impact on livestock production. Nematodicidal drugs, such as fenbendazole (FBZ) or its oxidized metabolite oxfendazole (OFZ), can be used along with the trematodicidal triclabendazole (TCBZ), to broaden the spectrum of anthelmintic activity. However, co-exposure to these compounds could lead to drug-drug (D-D) interactions and eventually alter the clinical profile of each active principle. The aim of this study was to assess the presence of such interactions by means of two in vitro models, namely bovine liver microsomal fractions and bovine precision-cut liver slices (PCLSs). To this end, an in vitro assessment involving incubation of FBZ and TCBZ or a combination of FBZ and TCBZ was carried out. Results with microsomal fractions showed a 78.4% reduction (p = .002) in the rate of OFZ production upon co-incubation, whereas the sulfoxide metabolite of TCBZ (TCBZSO) exhibited a decreasing tendency. With PCLS, OFZ accumulation in the incubation medium increased 1.8-fold upon co-incubation, whereas TCBZSO accumulation decreased by 28%. The accumulation of FBZ and OFZ in the liver tissue increased upon 2-hr co-incubation, from 2.1 ± 1.5 to 18.2 ± 6.1 (p = .0009) and from 0.4 ± 0.1 to 1.3 ± 0.3 nmol (p = .0005), respectively. These results confirm the presence of D-D interactions between FBZ and TCBZ. Further studies are needed to determine the extent of involvement of drug-metabolizing enzymes and membrane transporters in interactions between compounds largely used in livestock production systems.


Assuntos
Benzimidazóis/farmacocinética , Bovinos , Fenbendazol/farmacocinética , Fígado/metabolismo , Microssomos Hepáticos/metabolismo , Albendazol/farmacocinética , Animais , Anti-Helmínticos/farmacocinética , Interações Medicamentosas , Manejo de Espécimes , Triclabendazol
2.
Phys Rev Lett ; 118(15): 152502, 2017 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-28452556

RESUMO

Angular distributions of the elastic, inelastic, and breakup cross sections of the halo nucleus ^{11}Be on ^{197}Au were measured at energies below (E_{lab}=31.9 MeV) and around (39.6 MeV) the Coulomb barrier. These three channels were unambiguously separated for the first time for reactions of ^{11}Be on a high-Z target at low energies. The experiment was performed at TRIUMF (Vancouver, Canada). The differential cross sections were compared with three different calculations: semiclassical, inert-core continuum-coupled-channels and continuum-coupled-channels ones with including core deformation. These results show conclusively that the elastic and inelastic differential cross sections can only be accounted for if core-excited admixtures are taken into account. The cross sections for these channels strongly depend on the B(E1) distribution in ^{11}Be, and the reaction mechanism is sensitive to the entanglement of core and halo degrees of freedom in ^{11}Be.

3.
Vet Pathol ; 52(3): 465-75, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-24964921

RESUMO

Clostridium perfringens type D causes enterotoxemia in sheep and goats. The disease is mediated by epsilon toxin (ETX), which affects the cerebrovascular endothelium, increasing vascular permeability and leading to cerebral edema. In the present study, we compared the distribution and severity of the cerebrovascular changes induced in lambs by C. perfringens type D strain CN1020, its isogenic etx null mutant, and the ETX-producing complemented mutant. We also applied histochemical and immunohistochemical markers to further characterize the brain lesions induced by ETX. Both ETX-producing strains induced extensive cerebrovascular damage that did not differ significantly between each other in nature, neuroanatomic distribution, or severity. By contrast, lambs inoculated with the etx mutant or sterile, nontoxic culture medium did not develop detectable brain lesions, confirming that the neuropathologic effects observed in these infections are dependent on ETX production. Lambs treated with the wild-type and complemented strains showed perivascular and mural vascular edema, as well as serum albumin extravasation, particularly severe in the cerebral white matter, midbrain, medulla oblongata, and cerebellum. Brains of animals inoculated with the ETX-producing strains showed decreased expression of glial fibrillary acidic protein and increased expression of aquaporin-4 in the end-feet processes of the astrocytes around blood vessels. Early axonal injury was demonstrated with anti-amyloid precursor protein immunohistochemistry. Perivascular accumulation of macrophages/microglia with intracytoplasmic albumin globules was also observed in these animals. This study demonstrates that ETX is responsible for the major cerebrovascular changes in C. perfringens type D-induced disease.


Assuntos
Encéfalo/patologia , Clostridium perfringens/patogenicidade , Enterotoxemia/patologia , Doenças dos Ovinos/patologia , Animais , Aquaporina 4/análise , Encéfalo/irrigação sanguínea , Química Encefálica , Clostridium perfringens/genética , Enterotoxemia/microbiologia , Proteína Glial Fibrilar Ácida/análise , Ovinos , Doenças dos Ovinos/microbiologia
4.
Vet Pathol ; 51(3): 624-7, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-23978840

RESUMO

Within a 24-hour period, 7 out of 200 three- to four-week-old pastured Katahdin lambs died after showing clinical signs of hemoglobinuria, red-tinged feces, weakness, and recumbency. One of the lambs that was examined clinically before natural death also had abdominal pain, trembling, tachycardia, and severe anemia with a packed cell volume of 4%. Pathologic findings included icterus, hemoglobinuric nephrosis, dark red urine, pulmonary edema, hydrothorax, splenomegaly, and acute centrilobular to midzonal hepatocellular degeneration and necrosis with cholestasis. The differential diagnoses and diagnostic workup to achieve the diagnosis are briefly discussed.


Assuntos
Clostridium perfringens , Morte Súbita/veterinária , Enterotoxemia/diagnóstico , Hemólise/fisiologia , Doenças dos Ovinos/diagnóstico , Doenças dos Ovinos/microbiologia , Doenças dos Ovinos/patologia , Animais , Morte Súbita/etiologia , Morte Súbita/patologia , Diagnóstico Diferencial , Enterotoxemia/patologia , Evolução Fatal , Conteúdo Gastrointestinal , Hemoglobinúria/veterinária , Técnicas Histológicas/veterinária , Hidrotórax/patologia , Hidrotórax/veterinária , Imuno-Histoquímica/veterinária , Icterícia/patologia , Icterícia/veterinária , Fígado/microbiologia , Pulmão/microbiologia , Nefrose/patologia , Nefrose/veterinária , Edema Pulmonar/patologia , Edema Pulmonar/veterinária , Ovinos , Esplenomegalia/patologia , Esplenomegalia/veterinária
5.
Polymers (Basel) ; 16(16)2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39204540

RESUMO

The mechanical testing of additively manufactured parts has largely relied on the existing standards developed for traditional manufacturing. While this approach leverages the investment made in current standards development, it inaccurately assumes that the mechanical response of additive manufacturing (AM) parts is identical to that of parts manufactured through traditional processes. When considering thermoplastic, material extrusion AM, the differences in response can be attributed to an AM part's inherent inhomogeneity caused by porosity, interlayer zones, and surface texture. Additionally, the interlayer bonding of parts printed with large-scale AM is difficult to adequately assess, as much testing is performed such that stress is distributed across many layer interfaces; therefore, the lack of AM-specific standards to assess interlayer bonding is a significant research gap. To quantify interlayer bonding via fracture toughness, double cantilever beam (DCB) testing has been used for some AM materials, and DCB has been generally used for a variety of materials including metal, wood, and laminates. Mode I DCB testing was performed on thermoplastic matrix composites printed with Big Area Additive Manufacturing (BAAM). Of particular interest was the notch shape and deflection speed during testing. The results examine the differences when using two notch types and three deflection speeds. The testing method introduced by the following paper differentiates itself from the ones described in the standards used by modernizing the methodology. This was conducted with the introduction of Digital Image Correlation (DIC) to gather displacement and load data simultaneously without human intervention.

6.
Infect Immun ; 81(7): 2405-14, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23630957

RESUMO

Clostridium perfringens type D causes disease in sheep, goats, and other ruminants. Type D isolates produce, at minimum, alpha and epsilon (ETX) toxins, but some express up to five different toxins, raising questions about which toxins are necessary for the virulence of these bacteria. We evaluated the contribution of ETX to C. perfringens type D pathogenicity in an intraduodenal challenge model in sheep, goats, and mice using a virulent C. perfringens type D wild-type strain (WT), an isogenic ETX null mutant (etx mutant), and a strain where the etx mutation has been reversed (etx complemented). All sheep and goats, and most mice, challenged with the WT isolate developed acute clinical disease followed by death in most cases. Sheep developed various gross and/or histological changes that included edema of brain, lungs, and heart as well as hydropericardium. Goats developed various effects, including necrotizing colitis, pulmonary edema, and hydropericardium. No significant gross or histological abnormalities were observed in any mice infected with the WT strain. All sheep, goats, and mice challenged with the isogenic etx mutant remained clinically healthy for ≥24 h, and no gross or histological abnormalities were observed in those animals. Complementation of etx knockout restored virulence; most goats, sheep, and mice receiving this complemented mutant developed clinical and pathological changes similar to those observed in WT-infected animals. These results indicate that ETX is necessary for type D isolates to induce disease, supporting a key role for this toxin in type D disease pathogenesis.


Assuntos
Toxinas Bacterianas/metabolismo , Infecções por Clostridium/patologia , Clostridium perfringens/patogenicidade , Cabras/microbiologia , Ovinos/microbiologia , Animais , Toxinas Bacterianas/genética , Clostridium perfringens/genética , Clostridium perfringens/metabolismo , Feminino , Técnicas de Inativação de Genes , Genes Bacterianos , Teste de Complementação Genética , Intestinos/microbiologia , Estimativa de Kaplan-Meier , Masculino , Camundongos , Viabilidade Microbiana , Mutação , Plasmídeos/genética , Plasmídeos/metabolismo , Virulência
7.
Am J Transplant ; 13(10): 2743-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23915309

RESUMO

Procurement of a facial vascularized composite allograft (VCA) should allow concurrent procurement of all solid organs and ensure their integrity. Because full facial procurement is time-intensive, "simultaneous-start" procurement could entail VCA ischemia over 12 h. We procured a total face osteomyocutaneous VCA from a brain-dead donor. Bedside tracheostomy and facial mask impression were performed preoperative day 1. Solid organ recovery included heart, lungs, liver, kidneys, and pancreas. Facial dissection time was 12 h over 15 h to diminish ischemia while awaiting recipient preparation. Solid organ recovery began at 13.5 h, during midfacial osteotomies, and concluded immediately after facial explantation. Facial thoracic and abdominal teams worked concurrently. Estimated blood loss was 1300 mL, requiring five units of pRBC and two units FFP. Urine output, MAP, pH and PaO2 remained normal. All organs had good postoperative function. We propose an algorithm that allows "face first, concurrent completion" recovery of a complex facial VCA by planning multiple pathways to expedient recovery of vital organs in the event of clinical instability. Beginning the recipient operation earlier may reduce waiting time due to extensive recipient scarring causing difficult dissection.


Assuntos
Algoritmos , Morte Encefálica , Face/cirurgia , Transplante de Face/métodos , Doadores de Tecidos/provisão & distribuição , Obtenção de Tecidos e Órgãos/métodos , Adulto , Pontos de Referência Anatômicos , Face/irrigação sanguínea , Humanos , Masculino , Adulto Jovem
8.
Phys Rev Lett ; 110(14): 142701, 2013 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-25166983

RESUMO

The inclusive breakup for the (11)Li + (208)Pb reaction at energies around the Coulomb barrier has been measured for the first time. A sizable yield of (9)Li following the (11)Li dissociation has been observed, even at energies well below the Coulomb barrier. Using the first-order semiclassical perturbation theory of Coulomb excitation it is shown that the breakup probability data measured at small angles can be used to extract effective breakup energy as well as the slope of B(E1) distribution close to the threshold. Four-body continuum-discretized coupled-channels calculations, including both nuclear and Coulomb couplings between the target and projectile to all orders, reproduce the measured inclusive breakup cross sections and support the presence of a dipole resonance in the (11)Li continuum at low excitation energy.

9.
Phys Rev Lett ; 109(26): 262701, 2012 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-23368554

RESUMO

The first measurement of the elastic scattering of the halo nucleus 11Li and its core 9Li on 208Pb at energies near the Coulomb barrier is presented. The 11Li+208Pb elastic scattering shows a strong reduction with respect to the Rutherford cross section, even at energies well below the barrier and down to very small scattering angles. This drastic change of the elastic differential cross section observed in 11Li+208Pb is the consequence of the halo structure of 11Li, as it is not observed in the elastic scattering of its core 9Li at the same energies. Four-body continuum-discretized coupled-channels calculations, based on a three-body model of the 11Li projectile, are found to explain the measured angular distributions and confirm that the observed reduction is mainly due to the strong Coulomb coupling to the dipole states in the low-lying continuum of 11Li. These calculations suggest the presence of a low-lying dipole resonance in 11Li close to the breakup threshold.

10.
Mater Today Bio ; 9: 100094, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33665603

RESUMO

Bioengineering of the human auricle remains a significant challenge, where the complex and unique shape, the generation of high-quality neocartilage, and shape preservation are key factors. Future regenerative medicine-based approaches for auricular cartilage reconstruction will benefit from a smart combination of various strategies. Our approach to fabrication of an ear-shaped construct uses hybrid bioprinting techniques, a recently identified progenitor cell population, previously validated biomaterials, and a smart scaffold design. Specifically, we generated a 3D-printed polycaprolactone (PCL) scaffold via fused deposition modeling, photocrosslinked a human auricular cartilage progenitor cell-laden gelatin methacryloyl (gelMA) hydrogel within the scaffold, and cultured the bioengineered structure in vitro in chondrogenic media for 30 days. Our results show that the fabrication process maintains the viability and chondrogenic phenotype of the cells, that the compressive properties of the combined PCL and gelMA hybrid auricular constructs are similar to native auricular cartilage, and that biofabricated hybrid auricular structures exhibit excellent shape fidelity compared with the 3D digital model along with deposition of cartilage-like matrix in both peripheral and central areas of the auricular structure. Our strategy affords an anatomically enhanced auricular structure with appropriate mechanical properties, ensures adequate preservation of the auricular shape during a dynamic in vitro culture period, and enables chondrogenically potent progenitor cells to produce abundant cartilage-like matrix throughout the auricular construct. The combination of smart scaffold design with 3D bioprinting and cartilage progenitor cells holds promise for the development of clinically translatable regenerative medicine strategies for auricular reconstruction.

11.
Rev Esp Anestesiol Reanim ; 56(1): 27-30, 2009 Jan.
Artigo em Espanhol | MEDLINE | ID: mdl-19284125

RESUMO

OBJECTIVE: To evaluate the effect of prehydration with hydroxyethyl starch 130/0.4 (Voluven) compared to lactated Ringer solution in laparoscopic cholecystectomy. PATIENTS AND METHODS: We performed a randomized single-blind clinical trial on patients classified as ASA 1 and 2. The exclusion criteria were hypertension, kidney failure, treatment with diuretics or other antihypertensive drugs, diabetes, and use of nonsteroidal anti-inflammatory drugs. Balanced general anesthesia with remifentanil and sevoflurane was used. The total volume of administered fluids (including prehydration) was 2 mL x kg(-1) x h(-1) fasting plus 5 mL x kg(-1) x h(-1) during surgery. Group 1 was prehydrated 30 minutes before surgery with 500 mL of lactated Ringer solution in group 1; in group 2 the same quantity of Voluven was used. Ringer solution was used in both groups to provide additional fluids. Blood pressure was kept within 20% above or below baseline values. Standard anesthetic monitoring was performed. Intraoperative diuresis and creatinine clearance were recorded. The groups were compared using the t test; a P value of 05 or less was considered significant. RESULTS: Twenty-nine patients were enrolled in the study. Diuresis and creatinine clearance were significantly higher in the group that received prehydration with Voluven. The mean (SD) creatinine clearance rate was 176.44 (1433) mL x min(-1) in group 1 and 61.90 (6.6) mL x min(-1) in group 2 (P = .036). The mean volume of urine excreted was 1.71 (0.06) mL x kg(-1) x h(-1) in group 1 and 0.47 (0.02) mL x kg(-1) x h(-1) in group 2 (P = .017). CONCLUSION: Prehydration with Voluven can be an effective measure for protecting renal function against the adverse effects of pneumoperitoneum in laparoscopic surgery.


Assuntos
Colecistectomia Laparoscópica , Diurese/efeitos dos fármacos , Hidratação , Derivados de Hidroxietil Amido/uso terapêutico , Taxa de Depuração Metabólica/efeitos dos fármacos , Pneumoperitônio Artificial/efeitos adversos , Pré-Medicação , Circulação Renal/efeitos dos fármacos , Adulto , Creatinina/sangue , Feminino , Humanos , Derivados de Hidroxietil Amido/administração & dosagem , Derivados de Hidroxietil Amido/farmacologia , Soluções Isotônicas/administração & dosagem , Soluções Isotônicas/farmacologia , Soluções Isotônicas/uso terapêutico , Masculino , Pessoa de Meia-Idade , Monitorização Intraoperatória , Lactato de Ringer
13.
Transplant Proc ; 39(2): 376-7, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17362734

RESUMO

Renal biopsy is currently the gold standard to assess the causes of renal allograft dysfunction. In the present study, we prospectively assessed the role of the renal allograft biopsy in the diagnosis and treatment of renal allograft dysfunction. Seven hundred and fifteen biopsies were performed in 399 patients. The anatomopathological results in group 1 (delayed graft function) were: 60.4% acute tubular necrosis, 17.6% acute rejection, 4.3% calcineurin inhibitor toxicity, and 17.7% other diagnoses; in group 2 (acute graft dysfunction): 42.3% acute rejection, 22% acute tubular necrosis, 8.4% calcineurin inhibitor toxicity, and 27.3% other diagnoses. Among patients with delayed graft function, 42.2% of biopsies led to a change in the treatment. In 60.5%, the biopsy of patients with acute dysfunction led to a change in the patient management. In our series, the result of the biopsy disagreed with the clinical diagnosis in 39.6% and 57.7% of cases, respectively. These results demonstrated that renal graft biopsy remains an indispensable tool for the accurate management of kidney transplant patients.


Assuntos
Transplante de Rim/patologia , Transplante de Rim/fisiologia , Complicações Pós-Operatórias/patologia , Adulto , Biópsia , Feminino , Rejeição de Enxerto/epidemiologia , Rejeição de Enxerto/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/classificação , Reoperação/estatística & dados numéricos , Estudos Retrospectivos , Transplante Homólogo/patologia , Transplante Homólogo/fisiologia
14.
Genet Mol Res ; 6(3): 482-91, 2007 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-17985300

RESUMO

(Co)variance components and genetic parameters were estimated for body weights of a Romosinuano herd located in Sinú Valley, Cordoba, Colombia. Restricted maximum likelihood methods were used with a univariate animal model for birth weight, weaning weight (270 days), 16-month weight (480 days), weaning daily gain, and post-weaning daily gain. Models included random animal direct and maternal genetic effects, maternal permanent environmental effect (c2), and sex-year-month of birth and age of dam, as fixed effects. Estimates of direct effect for birth weight, weaning weight, 480-day weight, weaning daily gain, and post-weaning daily gain were: 0.25 +/- 0.0001, 0.34 +/- 0.063, 0.33 +/- 0.066, 0.32 +/- 0.062, and 0.17 +/- 0.052, respectively. Estimates of direct maternal genetic effects were low and ranged from 0.06 +/- 0.003 for birth weight to 0.20 +/- 0.054 for weaning daily gain. The genetic correlations between direct and maternal genetic effects were negative and low for 480-day weight (-0.05 +/- 0.219) and showed values of -0.37 +/- 0.007, -0.34 +/- 0.133, -0.33 +/- 0.135, and -0.38 +/- 0.232 for birth, weaning weight, weaning, and post-weaning daily gain, respectively. Permanent environmental maternal effects were not significant; the highest values were found for weaning weight, and weaning daily gain (0.086 +/- 0.031 and 0.078 +/- 0.031, respectively). We conclude that direct and maternal effects should be included in a selection program for all of these traits, and also that selection of weaning weights would be the most productive way to improve performance in Romosinuano cattle.


Assuntos
Bovinos/crescimento & desenvolvimento , Bovinos/genética , Variação Genética , Algoritmos , Animais , Peso Corporal , Colômbia , Feminino , Masculino , Modelos Genéticos , Fenótipo , Análise de Regressão , Fatores Sexuais , Fatores de Tempo
16.
Arch Intern Med ; 147(2): 286-8, 1987 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3813746

RESUMO

Results of urine cultures from 26 male nursing home patients wearing external catheters, collected by a simple standardized technique, were compared with culture results from the same patients obtained by sterile in-and-out catheterization. The culture results were the same in 22 (85%) of the matched specimens, and specimens collected by the standardized technique were 100% sensitive and 94% specific in detecting significant growth of pathogenic organisms. In contrast, 13 (57%) of 23 specimens collected from patients with external catheters by the nursing home staff using their routine technique yielded three or more organisms and were considered contaminated. These results suggest that it is possible to obtain a urine specimen that reflects bladder urine in the vast majority of patients with external catheters, and thus potentially avoid the need for in-and-out catheterization when diagnosing and planning treatment for urinary tract infections in this population.


Assuntos
Manejo de Espécimes/métodos , Cateterismo Urinário , Urina/microbiologia , Idoso , Humanos , Masculino , Casas de Saúde , Incontinência Urinária/terapia
17.
Acta Ortop Mex ; 29(1): 40-5, 2015.
Artigo em Espanhol | MEDLINE | ID: mdl-26999925

RESUMO

BACKGROUND: In Mexico low back pain is a very frequent symptom in the orthopedic practice. It is an important cause of work absenteeism, it is difficult to diagnose due to its various etiologies, and its treatment should be carefully chosen as, according to the World Health Organization, only 4% of patients require surgery. OBJECTIVE: To determine the frequency of low back pain at Hospital Angeles Mocel during a two-year period, and analyze the various etiologies and the treatment provided to patients. MATERIAL AND METHODS: The data base of the Orthopedics and Traumatology Service at Hospital Angeles Mocel was analyzed. It consisted of 246 patients over'18 years of age admitted with a diagnosis of low back pain. Frequency, sex, age, etiology and treatment were analyzed. RESULTS: At this hospital low back pain ranks second among the causes for hospital admission at the Orthopedics and Traumatology Service. Frequency is 13.5%; the most frequent age group affected is 31-45 years (36.9%); females were predominant (53.6%). Most cases admitted for low back pain were acute and had a posttraumatic etiology (90% of cases). CONCLUSION: Low back pain is a frequent reason for visiting the doctor worldwide. Epidemiologic studies about the frequency, etiology and treatment of low back pain are scarce in Mexico, even though it is one of the major causes for hospital admission at a private hospital.


Assuntos
Hospitalização/estatística & dados numéricos , Dor Lombar/epidemiologia , Ferimentos e Lesões/complicações , Adolescente , Adulto , Idoso , Feminino , Hospitais Privados , Humanos , Dor Lombar/etiologia , Dor Lombar/terapia , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Ferimentos e Lesões/epidemiologia , Adulto Jovem
18.
Am J Med ; 92(6): 607-14, 1992 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1605142

RESUMO

PURPOSE: Following implementation of special measures to control a nosocomial outbreak of methicillin-resistant Staphylococcus aureus (MRSA), we used immunoblot typing in conjunction with antimicrobial susceptibility testing to investigate the epidemiology of this event and to determine whether this outbreak represented the failure of infection control measures to limit the spread of previously endemic MRSA strains or the introduction of a new strain of MRSA. MATERIALS AND METHODS: Isolates of MRSA recovered from hospitalized patients were initially categorized on the basis of antimicrobial susceptibility results. Organisms susceptible to ciprofloxacin and/or trimethoprim/sulfamethoxazole were recovered from patients at a relatively constant rate prior to December 1988 and were categorized as endemic isolates. Subsequently, there was an outbreak due to organisms resistant to both of these antibiotics; these were therefore categorized as outbreak isolates. Isolates were later characterized by immunoblot typing. Prior to this analysis, isolates were given code numbers so that clinical and epidemiologic data as well as resistance patterns were not known until this testing was complete. RESULTS: Between January 1986 and November 1988, an average of 3.9 patients per month acquired nosocomial MRSA in the Sepulveda Veterans Administration Medical Center. In contrast, from December 1988 to October 1989, 369 MRSA isolates were collected from 125 patients (an average of 11.4 patients per month). Prior to December 1988, all tested nosocomial isolates of MRSA were susceptible to ciprofloxacin and/or to trimethoprim/sulfamethoxazole. In contrast, the outbreak was due to spread of MRSA isolates resistant to these antibiotics. Immunoblot typing of 204 isolates from 98 individuals identified five distinct immunoblot types of which types B and C were by far the most common. Type B was highly associated with outbreak isolates, whereas type C was associated with endemic isolates (p less than 0.001). All sequential isolates from single patients that belonged to different susceptibility categories demonstrated discordant immunoblot types. In contrast, concordant immunoblot types were observed for 25 of 27 sequential isolates that displayed minor variations in antimicrobial resistance. The institution of more stringent infection control measures was followed by the return of nosocomial MRSA acquisition rates to pre-outbreak levels. Although novobiocin and trimethoprim/sulfamethoxazole were extensively used to treat patients harboring outbreak and endemic isolates, respectively, in no instance was the initial MRSA isolate from any patient resistant to novobiocin and only 6% of initial endemic isolates displayed trimethoprim/sulfamethoxazole resistance. A modest, significant increase in the resistance of endemic isolates to various other antimicrobial agents was noted however. CONCLUSION: Immunoblot analyses provided strong, corroborative evidence that at least two separate strains of MRSA were present during the outbreak and that a newly introduced strain with a distinctive antimicrobial resistance pattern was primarily responsible for the rapid spread of MRSA during the outbreak. The observation that previously effective infection control measures failed to prevent the nosocomial spread of a newly introduced community-acquired MRSA strain suggests that a single set of control measures may not be equally efficacious against all strains of MRSA. In this regard, previously reported variations in resistance to topical antimicrobials and/or antiseptics, and differences in virulence factors such as colonization potential, invasiveness, and survival on fomites, may warrant further study. Control of the outbreak strain of MRSA in our institution did occur after the implementation of more strenuous isolation procedures.(ABSTRACT TRUNCATED)


Assuntos
Portador Sadio/epidemiologia , Infecção Hospitalar/epidemiologia , Surtos de Doenças/estatística & dados numéricos , Resistência a Meticilina , Infecções Estafilocócicas/epidemiologia , Staphylococcus aureus , California/epidemiologia , Portador Sadio/microbiologia , Portador Sadio/prevenção & controle , Infecção Hospitalar/microbiologia , Infecção Hospitalar/prevenção & controle , Surtos de Doenças/prevenção & controle , Estudos de Avaliação como Assunto , Hospitais de Veteranos , Humanos , Immunoblotting , Incidência , Controle de Infecções/métodos , Controle de Infecções/organização & administração , Testes de Sensibilidade Microbiana , Novobiocina/uso terapêutico , Doenças Profissionais/epidemiologia , Doenças Profissionais/microbiologia , Doenças Profissionais/prevenção & controle , Política Organizacional , Recursos Humanos em Hospital , Prevalência , Estações do Ano , Sorotipagem , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/prevenção & controle , Resistência a Trimetoprima , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico
19.
Chest ; 112(4 Suppl): 272S-275S, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9337303

RESUMO

Mesothelioma is a rare disease for which neither single modality nor bimodality therapy improves survival. For this reason, from 1980 to 1995, we used trimodality therapy in an attempt to improve survival in selected patients at Brigham and Women's Hospital and Dana-Farber Cancer Institute. One hundred twenty patients underwent trimodality treatment involving extrapleural pneumonectomy followed by combination chemoradiotherapy. Twenty-seven women and 93 men (mean age, 56 years) were evaluable for response and treatment-related morbidity. The operative mortality rate was 5%, and 22% of patients experienced major morbidity. Cell type and nodal status were significant prognostic variables. The respective 2- and 5-year survival rates were 45% and 22% overall, 70% and 37% for patients with epithelial cell type, 20% and 0% for patients with sarcomatous or mixed-histologic-type tumors, and 74% and 39% for patients who were node-negative with epithelial histologic type. Positive resection margins impacted survival only in the case of full-thickness, transdiaphragmatic invasion. A revised staging system stratified survival with median intervals of 22, 17, and 11 months for stages I, II, and III disease, respectively (p=0.04). Thus, extrapleural pneumonectomy with adjuvant therapy is appropriate and effective treatment for patients with stage I disease according to the revised staging system.


Assuntos
Mesotelioma/terapia , Neoplasias Pleurais/terapia , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biópsia , Terapia Combinada , Feminino , Seguimentos , Humanos , Masculino , Mesotelioma/patologia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Pleurais/patologia , Pneumonectomia , Estudos Retrospectivos , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento
20.
Biomol Eng ; 19(2-6): 239-42, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12202189

RESUMO

In this work, we describe a technique for the in-situ observation of cells adhered on opaque biomaterial surfaces. The visualisation of the morphology of cells adhered onto a surface allows to derive nuclear apoptotic signs or even the existence of organisation between groups of these cells. The technique is based on the use of an auto-immune reaction combined with a fluorescent agent that allows a direct inspection of the cell behaviour. The versatility of the technique is demonstrated by presenting several examples with different cultured cells (human chondrosarcome cells (CSRCs) and pluripotential mesenchymal stem cells (MSCs) from bone marrow) seeded over two different Ti-based surfaces (TiO(2) and TiN, respectively). These in-vitro observations are compared with the behaviour of the same cells on bare TiAlV alloy. From our results it is concluded that both TiO(2) and TiN surfaces show enhanced biological responses.


Assuntos
Condrossarcoma/imunologia , Condrossarcoma/patologia , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/imunologia , Teste de Materiais/métodos , Titânio , Ligas , Adesão Celular/imunologia , Divisão Celular , Células Cultivadas , Materiais Revestidos Biocompatíveis , Citoesqueleto , Imunoensaio de Fluorescência por Polarização/métodos , Humanos , Mesoderma/imunologia
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