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1.
Artículo en Inglés | MEDLINE | ID: mdl-38546666

RESUMEN

BACKGROUND: Lower doses of irradiation (≤ 5 Mrad) during the manufacture of highly crosslinked polyethylene acetabular liners may result in less crosslinking and an increased wear rate. Radiostereometric analysis (RSA) studies have found that wear of more highly irradiated highly crosslinked polyethylene liners (7 to 10 Mrad) decreases at longer-term follow-up compared with earlier reports of the same cohorts. Although wear of 5-Mrad irradiated liners appears to increase at midterm follow-up, it is unclear whether that remains true at longer follow-up. QUESTIONS/PURPOSES: We asked: (1) In patients who underwent THA with a 5-Mrad highly crosslinked polyethylene liner, what is the wear rate evaluated with RSA during the first 14 years? (2) Does the wear rate decrease after 6 years in situ? METHODS: This is a brief follow-up of prior RSA studies performed at 2 and 6 years. We prospectively reviewed the longer-term wear rate in 13 patients who underwent primary THAs with the same design of a 5-MRad irradiated crosslinked acetabular liner and a 28-mm cobalt-chromium articulation. Of the initial 30 patients who were enrolled, 13 (43%) were available at the 14-year timepoint; nine patients had died, 1 patient had withdrawn, 1 had an intraoperative fracture, 3 patients were too infirm to have radiographs, 2 had no baseline RSA radiographs, and 1 had poor-quality RSA images. Tantalum markers were inserted during surgery, and all patients had RSA radiographic examinations at 1 week, 6 months, and 1, 2, 6, and 14 years postoperatively. RESULTS: The mean ± standard deviation proximal, 2D, and 3D wear rates calculated between 1 year and 14 years were 0.019 ± 0.013 mm, 0.022 ± 0.015 mm, and 0.025 ± 0.019 mm per year, respectively. No patient had proximal 2D or 3D wear rates exceeding 0.06 mm per year. An increasing wear rate over time was measured for proximal and 2D wear rates between 6 and 14 years (0.024 and 0.030 mm per year) compared with that between 1 and 6 years (0.008 and 0.010 mm per year; p = 0.03). CONCLUSION: The proximal, 2D, and 3D wear of a highly crosslinked polyethylene liner produced using 5-Mrad radiation remains low in the longer-term. With the small numbers available in a long-term RSA study such as this, we confirmed that the wear rate did not decrease at longer-term follow-up, unlike previous RSA studies of more highly irradiated highly crosslinked polyethylene liners. Nevertheless, the wear rate remains very low and below the threshold typically associated with the development of osteolysis (0.1 mm/year of wear). This should provide assurance to orthopaedic surgeons monitoring patients with this 5-Mrad irradiated liner in situ, while providing useful information to manufacturers of future highly crosslinked polyethylene liners. LEVEL OF EVIDENCE: Level IV therapeutic study.

2.
Bone Jt Open ; 4(11): 839-845, 2023 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-37926113

RESUMEN

Aims: Radiostereometric analysis (RSA) is the most accurate radiological method to measure in vivo wear of highly cross-linked polyethylene (XLPE) acetabular components. We have previously reported very low wear rates for a sequentially irradiated and annealed X3 XLPE liner (Stryker Orthopaedics, USA) when used in conjunction with a 32 mm femoral heads at ten-year follow-up. Only two studies have reported the long-term wear rate of X3 liners used in conjunction with larger heads using plain radiographs which have poor sensitivity. The aim of this study was to measure the ten-year wear of thin X3 XLPE liners against larger 36 or 40 mm articulations with RSA. Methods: We prospectively reviewed 19 patients who underwent primary cementless THA with the XLPE acetabular liner (X3) and a 36 or 40 mm femoral head with a resultant liner thickness of at least 5.8 mm. RSA radiographs at one week, six months, and one, two, five, and ten years postoperatively and femoral head penetration within the acetabular component were measured with UmRSA software. Of the initial 19 patients, 12 were available at the ten-year time point. Results: The median proximal, 2D, and 3D wear rates calculated between one and ten years were all less than 0.005 mm/year, with no patient recording a proximal wear rate of more than 0.021 mm/year. Importantly, there was no increase in the wear rate between five and ten years. Conclusion: The very low wear rate of X3 XLPE liners with larger articulations remains encouraging for the future clinical performance of this material.

3.
Mult Scler Relat Disord ; 79: 105024, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37783196

RESUMEN

BACKGROUND: In this cross sectional study, we used MRF to investigate tissue properties of normal-appearing white matter, gray matter, and lesions in relapsing remitting MS (n = 21), secondary progressive MS (n = 16) and healthy controls (n = 9). A FISP-based MRF sequence was used for acquisition, imaging time 5 min 15 s. MRF T1 and T2 relaxation times were measured from lesional tissue, normal-appearing frontal white matter, corpus callous, thalamus, and caudate. Differences between healthy controls and MS were examined using ANCOVA adjusted for age and sex. Spearman rank correlations were assessed between T1 and T2 relaxation times and clinical measures. OBJECTIVES: To examine brain T1 and T2 values using magnetic resonance fingerprinting (MRF) in healthy controls and MS. METHODS: The subjects included 21 relapsing-remitting (RR) MS, 16 secondary progressive (SP) MS, and 9 age- and sex-matched HC without manifest neurological disease participating in a longitudinal MRI study. A 3T/ FISP-based MRF sequence was acquired. Regions of interest were drawn for lesions and normal appearing white matter. ANCOVA adjusted for age and sex were used to compare the groups with significance set at 0.05. RESULTS: A step-wise increase in T1 and T2 relaxation times was found between healthy controls, relapsing remitting MS, and secondary progressive MS. Significant differences were found in T1 and T2 between MS and healthy controls in the frontal normal-appearing white matter, corpus callosum, and thalamus (p < 0.04 for all). Significant differences in T1 and T2 between RR and SPMS were found in the frontal normal-appearing white matter and T2 lesions (p < 0.02 for all). T1 relaxation from the frontal normal-appearing white matter correlated with the Expanded Disability Status Scale [ρ = 0.62, p < 0.001], timed 25 foot walk (ρ = 0.45, p = 0.01), 9 hole peg test (ρ = 0.62, p < 0.001), and paced auditory serial addition test (ρ = -0.4, p = 0.01). CONCLUSION: These results suggest that MRF may be a clinically feasible quantitative approach for characterizing tissue damage in MS.


Asunto(s)
Esclerosis Múltiple Recurrente-Remitente , Esclerosis Múltiple , Humanos , Esclerosis Múltiple/diagnóstico por imagen , Esclerosis Múltiple/patología , Estudios Transversales , Imagen por Resonancia Magnética/métodos , Espectroscopía de Resonancia Magnética , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Esclerosis Múltiple Recurrente-Remitente/diagnóstico por imagen , Esclerosis Múltiple Recurrente-Remitente/patología
4.
J Nutr ; 152(4): 1006-1014, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-36967157

RESUMEN

BACKGROUND: Postmenopausal women with higher visceral adipose tissue (VAT) present with suppressed bone resorption (lower C-terminal crosslinking telopeptide of type I collagen; CTX-1) and turnover (lower osteocalcin) but whether this blunts the effect of calcium is unknown. OBJECTIVES: The primary outcome of this study was the effect of VAT on changes in CTX-1 after intake of 2 forms of calcium. Secondary outcomes included changes in parathyroid hormone (PTH), serum calcium, phosphorus, and alkaline phosphatase (ALP). METHODS: Randomized open three period crossover trial conducted between 2017 and 2019 at the University of South Australia among 77 lean and overweight postmenopausal women (53-79 y) with BMI <25 kg/m2 and >27 kg/m2, respectively. Participants received a single dose of milk (1000 mg calcium), calcium carbonate tablet (1000 mg calcium), and fruit juice (no calcium) in random order with a 7-d washout period. Blood samples were collected at baseline and hourly for 5 h. Data was analyzed by repeated measures ANOVA of log-transformed data. RESULTS: At baseline, women with higher VAT had significantly lower CTX-1 and higher PTH (44% lower and 30% higher, respectively, between Q4 and Q1, P < 0.0001). VAT had no influence on the acute changes in CTX-1 or PTH with calcium or juice. A suppression of 44% in CTX-1 was seen with calcium carbonate and milk and a suppression of 18% with juice. PTH was suppressed more with calcium carbonate (47%) compared to milk (22%). Milk calcium reduced PTH and CTX-1 at 2 h, whereas calcium carbonate reduced PTH in 1 h. The suppression in CTX-1 was slower with lowest concentrations at 4-5 h. CONCLUSIONS: Intake of 1000 mg calcium from milk or from calcium carbonate is effective in acutely suppressing bone resorption in postmenopausal women irrespective of visceral fat. This trial is registered at http://www.ANZCTR.org.au/ACTRN12617000779370.aspx as ACTRN 12617000779370).


Asunto(s)
Resorción Ósea , Carbonato de Calcio , Humanos , Femenino , Animales , Colágeno Tipo I , Grasa Intraabdominal , Estudios Cruzados , Sobrepeso , Posmenopausia , Leche , Calcio , Hormona Paratiroidea , Calcio de la Dieta , Biomarcadores
5.
J Vet Med Educ ; 49(2): 179-186, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33950794

RESUMEN

Practical skills are essential in the veterinary nursing curriculum. Given the increasing implementation of video recording in higher education, this study explored the feasibility and benefits of video recording as a classroom tool in professional education. Concerns regarding the inability to monitor individual students' performance during their laboratory course promoted the implementation of video recording-a blended learning method-in a veterinary nursing course. The approach was personalized for this study, particularly for the Gram staining skill. Students submitted video recordings demonstrating the progression of their skills development, and the instructor reviewed the recordings for assessment. The Participant Perception Indicator, a self-assessment, was used to determine students' experience, knowledge, and confidence gained after performing the skill. Video recording helped students to identify areas for self-improvement. It is also a helpful tool for instructors to ensure that students are meeting the learning standards. The results suggest that the use of video recording in learning Gram staining skills was effective. The evidence-based approach maximized students' learning and engagement, and it improved individualized assessment by the instructor and enabled the instructor to provide feedback on students' performance. During this period of increasing reliance on online teaching and learning, video recording in a classroom environment could be more widely used by instructors.


Asunto(s)
Bachillerato en Enfermería , Educación en Veterinaria , Estudiantes de Enfermería , Animales , Competencia Clínica , Bachillerato en Enfermería/métodos , Humanos , Autoevaluación (Psicología) , Coloración y Etiquetado/veterinaria , Grabación en Video
6.
J Nutr ; 152(4): 1006-1014, 2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-34751787

RESUMEN

BACKGROUND: Postmenopausal women with higher visceral adipose tissue (VAT) present with suppressed bone resorption (lower C-terminal crosslinking telopeptide of type I collagen; CTX-1) and turnover (lower osteocalcin) but whether this blunts the effect of calcium is unknown. OBJECTIVES: The primary outcome of this study was the effect of VAT on changes in CTX-1 after intake of 2 forms of calcium. Secondary outcomes included changes in parathyroid hormone (PTH), serum calcium, phosphorus, and alkaline phosphatase (ALP). METHODS: Randomized open three period crossover trial conducted between 2017 and 2019 at the University of South Australia among 77 lean and overweight postmenopausal women (53-79 y) with BMI <25 kg/m2 and >27 kg/m2, respectively. Participants received a single dose of milk (1000 mg calcium), calcium carbonate tablet (1000 mg calcium), and fruit juice (no calcium) in random order with a 7-d washout period. Blood samples were collected at baseline and hourly for 5 h. Data was analyzed by repeated measures ANOVA of log-transformed data. RESULTS: At baseline, women with higher VAT had significantly lower CTX-1 and higher PTH (44% lower and 30% higher, respectively, between Q4 and Q1, P < 0.0001). VAT had no influence on the acute changes in CTX-1 or PTH with calcium or juice. A suppression of 44% in CTX-1 was seen with calcium carbonate and milk and a suppression of 18% with juice. PTH was suppressed more with calcium carbonate (47%) compared to milk (22%). Milk calcium reduced PTH and CTX-1 at 2 h, whereas calcium carbonate reduced PTH in 1 h. The suppression in CTX-1 was slower with lowest concentrations at 4-5 h. CONCLUSIONS: Intake of 1000 mg calcium from milk or from calcium carbonate is effective in acutely suppressing bone resorption in postmenopausal women irrespective of visceral fat. This trial is registered at http://www.ANZCTR.org.au/ACTRN12617000779370.aspx as ACTRN 12617000779370).


Asunto(s)
Colágeno Tipo I , Grasa Intraabdominal , Animales , Biomarcadores , Calcio , Carbonato de Calcio , Estudios Cruzados , Femenino , Humanos , Leche , Sobrepeso , Hormona Paratiroidea , Posmenopausia
7.
Artículo en Inglés | MEDLINE | ID: mdl-33819798

RESUMEN

LC-MS/MS has recently emerged as the best-practice for simultaneous analysis of vitamin D metabolites. We have developed and validated an LC-MS/MS method for simultaneous quantification of 25(OH)D3, 24,25(OH)2D3, and 3-epi-25(OH)D3 in human serum. These three metabolites were extracted from 50 µL of serum by acetonitrile protein precipitation followed by salting-out of acetonitrile. DAPTAD (4-(4'-dimethylaminophenyl)-1,2,4-triazoline-3,5-dione) was used to derivatize the extracted metabolites and their deuterated isotope internal standards. Chromatographic separation was achieved on a UPLC C18 column (Waters® ACQUITY 100 × 2.1 mm, 1.7 µm) utilizing 0.1% formic acid and acetonitrile as mobile phases. Limits of quantification were 1 ng/mL for 25(OH)D3 and 0.1 ng/mL for 24,25(OH)D3 and 3-epi-25(OH)D3. In-house and external Vitamin D External Quality Assessment Scheme (DEQAS) quality control sample analysis revealed satisfactory method accuracy. Within-analytical batch and between analytical batches precision were <15%. Extraction recovery for the three analytes were all ˃ 85% and all showed adequate autosampler, bench-top and freeze-thaw stability. Inter-methodological comparison of 25(OH)D3 results in patient serum samples revealed systematic and proportional differences between our method and DiaSorin® Liaison immunoassay, however a good agreement with an independent LC-MS/MS method was found.

8.
Anaerobe ; 69: 102344, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33588043

RESUMEN

Fusobacterium necrophorum, a Gram-negative anaerobe, is the primary etiologic agent of liver abscesses of beef cattle. The bacterium, a member of the microbial community of the rumen, travels to the liver via portal circulation to cause abscesses. The severity of liver abscesses vary from mild with one or two small abscesses to severe with medium to large multiple abscesses. Leukotoxin, a secreted protein, is the critical virulence factor involved in the infection. Our objective was to compare leukotoxin production between strains of F. necrophorum isolated from mild and severe liver abscesses collected from slaughtered cattle. The quantification of leukotoxin was based on assays to measure cytotoxicity and protein antigen concentration. One-hundred strains, 50 from mild and 50 from severe abscesses, were utilized in the study. Cell-free supernatants were prepared from cultures grown in anaerobic broth at 9 and 24 h incubations. The leukotoxic activity was quantified by measuring cytotoxicity based on the release of lactic dehydrogenase from bovine lymphocyte cells, BL3, treated with the culture supernatant. Leukotoxin protein concentration was quantified by a sandwich ELISA assay with a leukotoxin-specific monoclonal antibody as the capture antibody. The leukotoxin activity and concentration were highly variable among the strains within each severity of liver abscesses. Although the leukotoxic activity was unaffected by incubation time, leukotoxin protein concentration was consistently higher at 24 h compared to 9 h incubation. Strains from severe liver abscesses had significantly higher leukotoxic activity and higher protein concentration compared to strains from mild liver abscesses (P < 0.0001) at both 9 and 24 h culture supernatants. Across all strains, the correlation coefficients between leukotoxic activity and leukotoxin concentration at 9 and 24 h were 0.14 (P = 0.17) and 0.47 (P < 0.0001), respectively. In conclusion, strains isolated from severe liver abscesses had significantly higher leukotoxic activities and leukotoxin protein concentrations compared to strains isolated from mild liver abscesses.


Asunto(s)
Exotoxinas/biosíntesis , Infecciones por Fusobacterium/microbiología , Infecciones por Fusobacterium/fisiopatología , Fusobacterium necrophorum/aislamiento & purificación , Fusobacterium necrophorum/metabolismo , Absceso Hepático/microbiología , Absceso Hepático/fisiopatología , Animales , Bovinos , Enfermedades de los Bovinos/microbiología , Enfermedades de los Bovinos/fisiopatología , Fusobacterium necrophorum/genética , Variación Genética , Genotipo , Índice de Severidad de la Enfermedad
9.
J Mol Struct ; 1230: 129868, 2021 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-33424034

RESUMEN

In view of the recent global pandemic caused by COVID-19 intense efforts have been devoted worldwide towards the development of an effective treatment for this disease. Recently, PDE4 inhibitors have been suggested to attenuate the cytokine storm in COVID-19 especially tumour necrosis factor alpha (TNF-α). In our effort we have explored the 2-substituted pyrrolo[2,3-b]quinoxalines for this purpose because of their potential inhibitory properties of PDE-4 / TNF-α. Moreover, several of these compounds appeared to be promising in silico when assessed for their binding affinities via docking into the N-terminal RNA-binding domain (NTD) of N-protein of SARS-CoV-2. A rapid and one-pot synthesis of this class of molecules was achieved via the Cu-catalyzed coupling-cyclization-desulfinylation of 3-alkynyl-2-chloroquinoxalines with t-butyl sulfinamide as the ammonia surrogate under ultrasound irradiation. Most of these compounds showed good to significant inhibition of TNF-α in vitro establishing a SAR (Structure Activity Relationship) within the series. One compound e.g. 3i was identified as a promising hit for which the desirable ADME and acceptable toxicity profile was predicted in silico.

10.
Artículo en Inglés | MEDLINE | ID: mdl-32512872

RESUMEN

The protective effect of obesity on bone health has been challenged by studies that link visceral adiposity to poor bone microarchitecture in young obese men and women. In postmenopausal women, the role of visceral adipose tissue (VAT) on bone turnover markers (BTMs) has not been investigated. The aim was to investigate the impact of VAT on BTMs, total bone mineral density (BMD), vitamin D metabolites and parathyroid levels (1-84 PTH) levels in postmenopausal women. A total of 76 lean and overweight women (without osteoporosis) underwent VAT measurements by dual-energy X-ray absorptiometry (iDXA). Blood samples were analyzed for serum C-terminal telopeptide of type 1 collagen (CTX-1), osteocalcin, bone-specific alkaline phosphatase (bone ALP), 1-84 PTH and vitamin D (25 hydroxyvitamin D, 25(OH)D) levels. VAT volumes ranged from 91 to 3392 cm3 and body mass index (BMI) ranged from 18.3 to 53.9 kg/m2. Women in the highest VAT quartile had significantly lower CTX-1, 25(OH)D, osteocalcin and the highest BMD (p < 0.05, for all). While VAT positively associated with BMD, after controlling for BMI, VAT was a negative predictor of BMD (ß = 0.368, p < 0.05). VAT was an independent negative predictor of CTX-1 (ß = -0.263, p < 0.05) and osteocalcin levels (ß = -0.277, p < 0.05). Among all measures of adiposity, VAT was the strongest independent determinant of BMD and BTMs. In clinical settings, VAT, and not BMI, may be a sensitive predictor of bone health in obese women.


Asunto(s)
Densidad Ósea , Grasa Intraabdominal , Obesidad , Osteoporosis Posmenopáusica , Posmenopausia , Absorciometría de Fotón , Anciano , Biomarcadores , Femenino , Humanos , Persona de Mediana Edad , Vitamina D
11.
J Clin Med ; 8(11)2019 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-31731695

RESUMEN

Vitamin D, along with calcium, is generally considered necessary for bone health and reduction of fractures. However, he effects of improving vitamin D status have not always been observed to improve bone mineral density (BMD). We have investigated whether varying vitamin D status in humans, as measured by serum 25(OH)D levels, relate to micro-structural and histomorphetric measures of bone quality and quantity, rather than density. Intertrochanteric trabecular bone biopsies and serum samples were collected from patients undergoing hip arthroplasty (65 females, 38 males, mean age 84.8 ± 8.3 years) at Royal Adelaide Hospital. Estimated GFR, serum ionized calcium, alkaline phosphatase, albumin, supplement and medication intake prior to surgery were taken from patient case records. Serum 25(OH)D, 1,25(OH)2D, and parathyroid hormone (PTH) levels were measured by immunoassays. Trabecular bone structural indices were determined by high-resolution micro-CT. Mean wall thickness (MWT) was measured on toluidine blue-stained histological sections. Bone mRNA levels for vitamin D metabolising enzymes CYP27B1 and CYP24A1 were measured by qRT-PCR. While serum 25(OH)D levels did not associate with bone volume/tissue volume (BV/TV%), serum 25(OH)D levels were strongly and independently associated with MWT (r = 0.81 p < 0.0001) with values significantly greater in patients with higher serum 25(OH)D levels. Furthermore, serum 25(OH)D levels were negatively associated with Bone Surface/Bone Volume (BS/BV) (r = -0.206, p < 0.05) and together with bone CYP27B1 and CYP24A1 mRNA accounted for 10% of the variability of BS/BV (p = 0.001). These data demonstrate that serum 25(OH)D is an independent positive predictor of micro-structural and bone formation measures and may be dependent, in part, on its metabolism within the bone.

13.
Nat Commun ; 10(1): 2140, 2019 05 13.
Artículo en Inglés | MEDLINE | ID: mdl-31086187

RESUMEN

Plasmodium sexual differentiation is required for malaria transmission, yet much remains unknown about its regulation. Here, we quantify early gametocyte-committed ring (gc-ring) stage, P. falciparum parasites in 260 uncomplicated malaria patient blood samples 10 days before maturation to transmissible stage V gametocytes using a gametocyte conversion assay (GCA). Seventy six percent of the samples have gc-rings, but the ratio of gametocyte to asexual-committed rings (GCR) varies widely (0-78%). GCR correlates positively with parasitemia and is negatively influenced by fever, not hematocrit, age or leukocyte counts. Higher expression levels of GDV1-dependent genes, ap2-g, msrp1 and gexp5, as well as a gdv1 allele encoding H217 are associated with high GCR, while high plasma lysophosphatidylcholine levels are associated with low GCR in the second study year. The results provide a view of sexual differentiation in the field and suggest key regulatory roles for clinical factors and gdv1 in gametocytogenesis in vivo.


Asunto(s)
Interacciones Huésped-Parásitos/fisiología , Malaria Falciparum/parasitología , Plasmodium falciparum/fisiología , Proteínas Protozoarias/fisiología , Diferenciación Sexual/fisiología , Factores de Edad , Niño , Preescolar , Femenino , Gametogénesis/fisiología , Genes Protozoarios/fisiología , Ghana , Humanos , Lisofosfatidilcolinas/sangre , Malaria Falciparum/sangre , Masculino , Parasitemia/parasitología , Plasmodium falciparum/aislamiento & purificación
14.
Anaerobe ; 56: 51-56, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30771459

RESUMEN

Fusobacterium necrophorum is a Gram negative, rod-shaped and aero tolerant anaerobe. In animals, it is an opportunistic pathogen frequently associated with necrotic infections, generally called necrobacillosis, such as calf diphtheria, foot rot and liver abscesses in cattle. Two subspecies exist: subsp. necrophorum and subsp. funduliforme. Among several virulence factors, leukotoxin (Lkt) is considered to be a major factor and a protective antigen. The objective of the study was to utilize BL3 cells and measure the release of lactic dehydrogenase to quantify Lkt activity of F. necrophorum. The assay was used to examine the effects of storage and handling conditions, growth media, polymyxin B addition on the cytotoxicity and evaluate Lkt activities of F. necrophorum strains isolated from bovine liver abscesses and foot rot. The Lkt activity peaked at 9 h of incubation. There was a significant decrease in the cytotoxicity measured in the samples after each freeze and thaw cycle. No difference was observed in the cytotoxicity for the samples handled aerobically versus anaerobically. Lkt activities of strains grown in anaerobic Brain-Heart Infusion broth were higher compared to Vegitone broth. A small reduction in the cytotoxicity activity was observed after the addition of polymyxin. The Lkt activity was consistently higher in strains of subsp. necrophorum than subsp. funduliforme of liver abscess origin. Among the strains isolated from cattle foot rot, Lkt activities of subsp. necrophorum strains appear to be much more variable. Use of BL3 cells in combination of lactic acid dehydrogenase assay appears to be a simple and valid assay to measure Lkt activity of F. necrophorum.


Asunto(s)
Enfermedades de los Bovinos/microbiología , Exotoxinas/toxicidad , Infecciones por Fusobacterium/veterinaria , Fusobacterium necrophorum/aislamiento & purificación , Fusobacterium necrophorum/patogenicidad , Factores de Virulencia/toxicidad , Animales , Bovinos , Línea Celular , Supervivencia Celular/efectos de los fármacos , Panadizo Interdigital/microbiología , Infecciones por Fusobacterium/microbiología , L-Lactato Deshidrogenasa/análisis , Absceso Hepático/microbiología , Absceso Hepático/veterinaria
15.
Vet Microbiol ; 215: 11-17, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29426400

RESUMEN

Bovine respiratory disease (BRD) is a major problem for the cattle industry that is triggered by various environmental stressors, pathogens and host responses. Mannheimia hemolytica, an important bacterial component of BRD, are present within the nasopharayngeal region of normal calves as commensal biofilm communities. However, following stress there are changes in the nasopharyngeal microenvironment that triggers the transition of the commensal M. haemolytica into a pulmonary pathogen. The factors responsible for this transition in- vivo are unknown. In this study we developed an in-vitro biofilm model and investigated the effect of three stress- related compounds: norepinephrine (NE), epinephrine (E), and substance P (SP) on M. haemolytica biofilms. Biofilm formation was demonstrated for 3 bovine nasal isolates of M. haemolytica by growing them in basal culture media, basal media with additional glucose, and basal media with a reduced pH. Increased glucose enhanced biofilm biomass for 2/3 isolates, but acidic media did not increase biofilm biomass when compared to biofilm biomass in basal media. When the biofilm was exposed to NE, E and SP, there was a dispersal of the biofilm which was most effective with E, followed by NE, and SP being the least effective. Using high - throughput scanning electron microscopy and confocal-imaging we confirmed our experimental data that treatment with NE, E and SP cause dispersion of M.haemolytica from biofilms.


Asunto(s)
Biopelículas/efectos de los fármacos , Enfermedades de los Bovinos/microbiología , Epinefrina/farmacología , Mannheimia haemolytica/efectos de los fármacos , Norepinefrina/farmacología , Infecciones por Pasteurellaceae/microbiología , Sustancia P/farmacología , Agonistas alfa-Adrenérgicos/farmacología , Animales , Bovinos , Células Cultivadas , Mannheimia haemolytica/patogenicidad , Mannheimia haemolytica/ultraestructura , Microscopía Confocal , Microscopía Electrónica de Rastreo , Neurotransmisores/farmacología , Estrés Fisiológico/efectos de los fármacos , Simbiosis
16.
Indian J Orthop ; 49(6): 630-6, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26806970

RESUMEN

The medial patellofemoral ligament (MPFL) is the primary stabilizer of the patellofemoral joint; its reconstruction has been recommended in adults over the past decade after recurrent patellar instability. However, there has been no standardized technique for reconstruction, therefore, ideal graft and technique for reconstruction are yet undetermined. However, dynamic MPFL reconstruction studies claim to be superior to other procedures as it is more anatomical. This preliminary study aims at assessing the outcomes of MPFL reconstruction in a dynamic pattern using hamstring graft. We performed this procedure in four consecutive patients with chronic patellar instability following trauma. MPFL reconstruction was done with hamstring tendons detached distally and secured to patellar periosteum after being passed through a bony tunnel in the patella without an implant and using the medial collateral ligament as a pulley. In all 4 knees, the MPFL reconstruction was isolated and was not associated with any other realignment procedures. No recurrent episodes of dislocation or subluxation were reported at 24 months followup.

17.
Environ Res ; 121: 71-8, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23177171

RESUMEN

Exposures to ambient diesel exhaust particles have been associated with respiratory symptoms and asthma exacerbations in children; however, epidemiologic evidence linking short-term exposure to ambient diesel exhaust particles with airway inflammation is limited. We conducted a panel study with asthmatic and nonasthmatic adolescents to characterize associations between ambient diesel exhaust particle exposures and exhaled biological markers of airway inflammation and oxidative stress. Over four weeks, exhaled breath condensate was collected twice a week from 18 asthmatics and 18 nonasthmatics (ages 14-19 years) attending two New York City schools and analyzed for pH and 8-isoprostane as indicators of airway inflammation and oxidative stress, respectively. Air concentrations of black carbon, a diesel exhaust particle indicator, were measured outside schools. Air measurements of nitrogen dioxide, ozone, and fine particulate matter were obtained for the closest central monitoring sites. Relationships between ambient pollutants and exhaled biomarkers were characterized using mixed effects models. Among all subjects, increases in 1- to 5-day averages of black carbon were associated with decreases in exhaled breath condensate pH, indicating increased airway inflammation, and increases in 8-isoprostane, indicating increased oxidative stress. Increases in 1- to 5-day averages of nitrogen dioxide were associated with increases in 8-isoprostane. Ozone and fine particulate matter were inconsistently associated with exhaled biomarkers. Associations did not differ between asthmatics and nonasthmatics. The findings indicate that short-term exposure to traffic-related air pollutants may increase airway inflammation and/or oxidative stress in urban youth and provide mechanistic support for associations documented between traffic-related pollutant exposures and respiratory morbidity.


Asunto(s)
Contaminantes Atmosféricos/toxicidad , Asma/metabolismo , Biomarcadores/análisis , Exposición a Riesgos Ambientales/efectos adversos , Inflamación/metabolismo , Estrés Oxidativo/efectos de los fármacos , Emisiones de Vehículos/toxicidad , Adolescente , Contaminantes Atmosféricos/análisis , Contaminación del Aire/efectos adversos , Contaminación del Aire/análisis , Pruebas Respiratorias/métodos , Dinoprost/análogos & derivados , Dinoprost/análisis , Femenino , Humanos , Concentración de Iones de Hidrógeno , Inflamación/etiología , Masculino , Ciudad de Nueva York , Dióxido de Nitrógeno/análisis , Ozono/análisis , Material Particulado/análisis , Hollín/análisis , Población Urbana , Emisiones de Vehículos/análisis , Adulto Joven
18.
Case Rep Orthop ; 2012: 452651, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23259123

RESUMEN

Skeletal muscle haemangiomas are uncommon soft tissue tumors; more than 90% are misdiagnosed initially. They present as chronic pain and swelling in a muscle with or without a history of trauma. Plain X-rays, bone scans, computerized tomography (CT) studies, and angiography studies may not always be specific for this tumor. Diagnostic ultrasound is an appropriate initial imaging modality for suspected haemangioma, although magnetic resonance imaging is the investigation of choice. Many treatment modalities for the symptomatic haemangiomas are available of which surgical excision is the most preferred. We present an unusual case of pain, swelling, and restriction of movements in the right knee following an episode of trauma in a 12-year-old boy who was being followed for 1 year by a general practioner and later referred to us. The patient was diagnosed to have intramuscular cavernous haemangioma in the vastus medialis by us for which he was treated by surgical excision and followed for 1 year and found to have no recurrence. The clinical features, radiological picture, pathological histology, diagnostic tools, and treatment options have been discussed.

19.
Foot (Edinb) ; 22(3): 247-51, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22560258

RESUMEN

Ankle dislocation without concomitant fracture is a rare phenomenon with only a few cases reported in literature. Our case report presents a male who sustained a closed anterolateral ankle dislocation without fractures following a road traffic accident. The patho-anatomy, principles of management and probable complications of this injury have been discussed.


Asunto(s)
Traumatismos del Tobillo/diagnóstico , Traumatismos del Tobillo/terapia , Luxaciones Articulares/diagnóstico , Luxaciones Articulares/terapia , Accidentes de Tránsito , Adulto , Traumatismos del Tobillo/etiología , Moldes Quirúrgicos , Humanos , Luxaciones Articulares/etiología , Masculino , Manipulación Ortopédica
20.
ACS Appl Mater Interfaces ; 3(7): 2643-54, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21688808

RESUMEN

Multifunctional graphene oxide/reduced graphene oxide (GO/RGO) composites were prepared through electrostatic interaction using biocompatible ingredients. Different functionalities were added to GO/RGO by anchoring materials such as native lactoferrin (NLf), NLf protected Au clusters (designated as Au@NLf), chitosan (Ch) and combinations thereof. Anchoring of Ch and NLf enhances the antibacterial property of RGO/GO. The addition of Ch to RGO/GO not only helped in forming stable dispersions but also helped in fabricating large (cm(2)) area films through a simple solvent evaporation technique. Functionalities such as photoluminescence were added to Ch-RGO/GO composites by anchoring Au@NLf on it. The composites thus formed showed stable luminescence in presence of various metal ions in the solid state. The composite showed reasonable stability against pH and temperature variations as well. The as-prepared films were transparent and the transparency could be modulated by controlling the concentration of RGO/GO in the composite. The antibacterial property and ability to form stable thin films may provide an opportunity to use such composites for medical and environmental remediation applications as well. Erasable patterns were fabricated on the film by stamping required patterns under compressive pressure. Luminescent patterns can be inscribed on the film and can be erased by simply wetting it. Such films with erasable information may be useful for security applications.

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