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1.
J Plast Reconstr Aesthet Surg ; 93: 18-23, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38608533

RESUMEN

BACKGROUND: Treatment of scalp malignancies may include the need for craniectomy. The decision to perform cranioplasty is not straightforward and is frequently subjective. The purpose of this study was to assess the clinical outcomes after reconstruction of complex scalp and calvarial defects by comparing patients with and without cranioplasty. METHODS: Retrospective review of the clinical records of a consecutive series of patients who underwent scalp soft tissue reconstruction after craniectomy for malignancy or osteoradionecrosis between 2014 and 2022 at Royal Melbourne Hospital was conducted. Demographics, previous treatments, surgical details, and post-operative complications were assessed. Traumatic injuries and decompressive craniectomies were excluded. Minimum follow-up of 6 months. RESULTS: Thirty-seven patients were included in the study. Indications for surgery included skin malignancies, osteoradionecrosis, or both. There was one reconstructive failure (in the non-cranioplasty group). Infection and metalware exposure were common complications in patients who underwent cranioplasty (38.5%). No patient developed neurological symptoms subsequent to craniectomy. One patient needed revision surgery due to esthetic reasons (cranioplasty group). Transposition flaps were associated with more complications and revision procedures. CONCLUSION: Combined scalp and calvarial defects pose a difficult reconstructive challenge. Stable soft tissue coverage is more reliably achieved with free flap reconstruction. Cranioplasty is not always mandatory and should be reserved for cases with a very large bony defect or when the defect is located in a cosmetically sensitive area.


Asunto(s)
Procedimientos de Cirugía Plástica , Cuero Cabelludo , Neoplasias Cutáneas , Cráneo , Humanos , Cuero Cabelludo/cirugía , Masculino , Femenino , Estudios Retrospectivos , Procedimientos de Cirugía Plástica/métodos , Cráneo/cirugía , Persona de Mediana Edad , Anciano , Neoplasias Cutáneas/cirugía , Colgajos Quirúrgicos , Osteorradionecrosis/cirugía , Adulto , Complicaciones Posoperatorias/cirugía , Anciano de 80 o más Años , Craneotomía/métodos , Craneotomía/efectos adversos , Reoperación/métodos , Neoplasias de Cabeza y Cuello/cirugía , Resultado del Tratamiento
2.
ANZ J Surg ; 94(4): 572-579, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38087881

RESUMEN

BACKGROUND: The proliferation of electric scooters globally has been associated with an increase in related injuries and consequent economic burden. This study aims to assess the injury patterns and the economic impact associated with electric scooter use in Melbourne, Australia. METHODS: A retrospective cohort study was conducted using hospital and registry data from January 2022 to January 2023. Data collected included demographic details, alcohol and helmet use, injury type and severity, operative treatment provided, and direct medical costs. The economic impact (in AUD) of the patient's emergency presentation and hospital admission was calculated. RESULTS: During the study period, 256 electric scooter related injuries were recorded, comprising 247 riders and nine pedestrians. The majority of patients were males (69%) with a median age of 29.5 (15-78). Alcohol use was reported by 34% and helmet use by 33%. Injuries most commonly affected the upper limb (53%) and head (50%), with abrasions (75%) and fractures (48%) being the most common type of injury sustained. The total hospital cost was $1 911 062, and the median cost was $1321.66 per patient (IQR: $479.37-$5096.65). CONCLUSION: Electric scooter usage, as observed through patient presentations to the Royal Melbourne Hospital, is associated with a considerable number of injuries, primarily among young males, and an ensuing substantial economic burden. The findings underscore the urgent need for improved safety measures to minimize electric scooter-related injuries and their clinical and economic repercussions.


Asunto(s)
Fracturas Óseas , Masculino , Humanos , Femenino , Estudios Retrospectivos , Fracturas Óseas/epidemiología , Hospitalización , Consumo de Bebidas Alcohólicas , Australia/epidemiología , Dispositivos de Protección de la Cabeza , Servicio de Urgencia en Hospital , Accidentes de Tránsito
3.
Artículo en Inglés | MEDLINE | ID: mdl-38997870

RESUMEN

It was the aim of the study to analyze the distribution and pattern of facial fractures following e-scooter trauma. Prospective audit data of facial fractures were retrospectively collected to investigate the impact of e-scooter hire, specifically in the form of facial fractures associated with their use. Data collected included patient demographics, mode of injury, date of injury, facial bones involved, presence of soft tissue injury, and factors associated with injury, including intoxication and helmet use. A total of 849 patients were treated for facial fractures during the study period, of which 34 were attributed to e-scooter use. One-half of those injured riding e-scooters were intoxicated, and one-quarter were wearing helmets. There have been an increasing number of facial fractures associated with e-scooter use following the start of the shared e-scooter trial. Zygomaticomaxillary complex fractures were the most common pattern of facial fracture seen. Most patients required surgical management of their injuries. Policymakers should consider how to improve the enforcement of current regulations, given the healthcare cost associated with the management of these preventable injuries.

4.
Cancers (Basel) ; 16(7)2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38610956

RESUMEN

A multidisciplinary approach to the management of tongue cancer is vital for achieving optimal patient outcomes. Nursing and allied health professionals play essential roles within the team. We developed symposia comprising a series of online lectures offering a detailed perspective on the role each discipline and consumer perspective has in the management of patients with tongue cancer. The topics, including epidemiology and prevention, diagnosis, treatment planning, surgery, adjuvant care, and the management of recurrent or metastatic disease, were thoroughly examined. The symposia highlighted the significance of fostering collaboration and continuous learning through a multidisciplinary approach. This initiative should be relevant to healthcare professionals, researchers, and policymakers striving to enhance patient outcomes in tongue cancer care through innovative collaboration.

5.
Artículo en Inglés | MEDLINE | ID: mdl-37282572

RESUMEN

BACKGROUND: Evidence of type 2 diabetes mellitus (T2DM) associated with hippocampal atrophy is reported by researchers all around the globe. The majority of such studies were conducted among the geriatric and elderly populations with other substantial co-morbid diseases. Hence, the present study aims to evaluate the hippocampal volume of T2DM subjects below 60 years without any concomitant disorders and assess the declarative memory. MATERIALS AND METHODS: The cross-sectional observational study was conducted among the ethnic population of Manipur. A total of 17 T2DM subjects and 17 healthy controls, who are apparently healthy, matched by age, sex, and comparable education, were enrolled in the study. Magnetic Resonance Imaging (MRI) of high-resolution sagittal structural T1-weighted anatomical sequence was acquired using a three-dimension magnetization-prepared rapid-acquisition gradient echo (MPRAGE). The hippocampus volume was measured using the volBrain Automated MRI Brain Volumetry System. Declarative memory was estimated by the Rey Auditory Verbal Learning Test (RAVLT). RESULTS: No statistically significant differences were found in hippocampal volume, and RAVLT scores between T2DM subjects, and healthy controls group (P > 0.05). CONCLUSIONS: The study data indicates that there is no particular hippocampal volume vulnerability in T2DM participants within the ethnic population of Manipur.

6.
Open Forum Infect Dis ; 9(1): ofab590, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35024372

RESUMEN

BACKGROUND: Adherence to guidelines for antibiotic prophylaxis is often poor and is an important target for antimicrobial stewardship programs. Prescribing audits that suggested poor adherence to guidelines in a plastic surgery department led to a targeted education program to bring antibiotic prescriptions in line with hospital guidelines. We reviewed whether this intervention was associated with changed perioperative prescribing and altered surgical outcomes, including the rate of surgical site infections, specifically looking at clean-contaminated head and neck tumor resections with free flap reconstruction. METHODS: A retrospective cohort study was performed on 325 patients who underwent clean-contaminated head and neck tumor resection and free flap reconstruction from January 1, 2013, to February 19, 2019. Patients were divided into 2 groups, those before (pre-intervention) and after (postintervention) the education campaign. We analyzed patient demographic and disease characteristics, intraoperative and postoperative factors, and surgical outcomes. RESULTS: Patients pre-intervention were prescribed longer courses of prophylactic antibiotics (median [interquartile range], 9 [8] vs 1 [1]; P < .001), more topical chloramphenicol ointment (21.82% vs 0%; P < .001), and more oral nystatin (36.9% vs 12.2%; P < .001). Patients postintervention had higher rates of recipient infections (36.11% vs 17.06%; P < .001) and donor site infections (6.94% vs 1.19%; P = .006). CONCLUSIONS: Following the education campaign, patients were prescribed shorter courses of prophylactic antibiotics, more of the recommended cefazolin-metronidazole regimen, and fewer topical antibiotics. However, patients also had a higher rate of surgical site infections.

7.
ANZ J Surg ; 91(12): 2610-2616, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33724659

RESUMEN

Microsurgical reconstructive head and neck cancer patients are at high risk of venous thromboembolism. The use of anticoagulation can reduce their risk; however, this also increases their bleeding risk. It is not clear whether the benefits of treatment outweigh the risks, and whether a specific post-operative anticoagulation regime is superior. The aim of this review is to evaluate the evidence pertaining to the risks and benefits of post-operative anticoagulation and to provide a rationale for its use in head and neck cancer patients receiving free flaps. The secondary aim was to determine the optimal post-operative anticoagulation regimen. A search was conducted in the PubMed and EMBASE databases identifying studies reporting venous thromboembolism rates in reconstructive head and neck cancer patients undergoing free flaps. These studies were reviewed for their eligibility. Outcomes measured were rates of venous thromboembolism, bleeding-related and microsurgical complications. A total of 306 studies were found from the search with another seven studies identified from citations of key articles. After assessment, nine studies were included. Venous thromboembolism rates ranged from 0.5% to 7% and the rates of bleeding-related complications ranged from 2.4% up to 29%. Anticoagulation appears to lower the risk of venous thromboembolism in this patient group, but also increases the bleeding risk. Risk stratification using the Caprini risk assessment model can help surgeons make decisions. For patients with cancer, low molecular weight heparin appears to be superior to heparin given twice daily but equal to heparin given three times daily and the bleeding risk of each medication appears similar.


Asunto(s)
Neoplasias de Cabeza y Cuello , Anticoagulantes/efectos adversos , Neoplasias de Cabeza y Cuello/cirugía , Humanos
8.
ANZ J Surg ; 91(12): 2624-2636, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33825306

RESUMEN

BACKGROUND: Lymphoedema is an incurable and progressive disease that affects not only physical function but overall quality of life. Surgical treatment options for the management of lymphoedema are being increasingly performed. This study aims to review post-operative health-related quality of life (HRQOL) following surgical treatment of lymphoedema. METHODS: A systematic search of the PubMed and Medline databases was performed from the date of their inception until September 2018 to evaluate HRQOL following different surgical options for the treatment of lymphoedema. RESULTS: One hundred and thirteen articles were identified. Twenty-one articles were included in the final review, comprising a total of 736 patients. HRQOL improvements appear to be sustained for at least 6-12 months post-operatively. In particular, major benefits were noted in the domains based around physical functioning. Patient satisfaction similarly mirrors HRQOL improvements, following an initial dip in the immediate post-operative period. CONCLUSION: All surgical treatment modalities for the management of lymphoedema confer significant HRQOL improvements across a diverse range of health domains, with this critical outcome of surgery an important pre-operative consideration. Recommendations for ongoing research are suggested.


Asunto(s)
Linfedema , Calidad de Vida , Humanos , Linfedema/etiología , Linfedema/cirugía
9.
ANZ J Surg ; 91(6): 1104-1109, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33438368

RESUMEN

BACKGROUND: Chest keloids are a difficult sub-group of scars to treat, likely secondary to the high wound tension in the area that promotes excessive fibroblast proliferation and collagen deposition. Excision and adjuvant radiotherapy has been demonstrated as an efficacious treatment for keloids in general, but no meta-analysis exists to support the claims for chest keloids. This study aims to identify the rate of recurrence after surgical resection and radiotherapy on patients with chest keloids. METHODS: A search was performed using Embase, MEDLINE, Pubmed and Cochrane database on 22 December 2018 for terms 'radiotherapy', 'keloid' and 'chest'. Papers included met a prospectively designed inclusion criteria assessed by multiple investigators. RESULTS: Twelve studies, including 1 randomized controlled trial, were included for a total of 400 patients with a chest keloid scar managed with surgical excision and adjuvant radiotherapy. Overall pooled-estimate of recurrence rate was 22% (95% CI 12-32%). Meta-regression did not demonstrate a significant effect for method of wound closure, type of radiotherapy, radiotherapy dose (BED10 ) and study type. CONCLUSION: Excision and adjuvant radiotherapy represents an effective method of treatment for chest keloids, however sufficient prospective data, including randomized controlled trials, did not yet exist to support these findings. Further studies with sufficient sub-group analysis for keloid location are required to add to the pool of literature that can be added to this meta-analysis.


Asunto(s)
Queloide , Humanos , Queloide/radioterapia , Queloide/cirugía , Recurrencia Local de Neoplasia/epidemiología , Recurrencia Local de Neoplasia/radioterapia , Recurrencia Local de Neoplasia/cirugía , Estudios Prospectivos , Radioterapia Adyuvante , Ensayos Clínicos Controlados Aleatorios como Asunto , Recurrencia , Resultado del Tratamiento
10.
ANZ J Surg ; 91(5): 962-968, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33844452

RESUMEN

BACKGROUND: The authors aimed to examine the differences in CT facial bone interpretation by the faciomaxillary surgeon and the radiologist, in order to improve communication gaps and subsequently, the quality and consistency of patient care. METHODS: This study was conducted at a level I tertiary trauma centre. Patients with facial trauma who were referred to the faciomaxillary unit following a facial CT examination from August 2017 to September 2018 were eligible for inclusion. The inclusion period was extended to 5 years for panfacial trauma patients. All consecutive patients that fulfilled the study inclusion criteria for each type of injury were included in the study (a total of 120 patients assigned to the following six categories: orbits, skull and skull base, zygomaticomaxillary complex, Le Fort pattern, mandible and pan-facial fractures). Faciomaxillary surgeons, blinded to the radiology report, were asked to provide a verbal description of the fractures. The surgical interpretation was compared to the radiology report and further analysed. RESULTS: Of the 120 cases, the same fractures were reported in 43 cases (35.8%). Both types of specialists noted the predominant and clinically relevant fractures in 106 cases (88.3%). The reports did not match in 14 cases (11.7%) and different terminology was used in 76 cases (63.3%), with agreement in 25% (95% CI: 18-34%), partial agreement in 11.7% (95% CI: 5.9-17.4%) and no agreement in 63.3% (95% CI: 54.7-72.0%) cases. CONCLUSION: Radiologists and faciomaxillary surgeons frequently differ in their assessment of facial fractures.


Asunto(s)
Fracturas Craneales , Cirujanos , Huesos Faciales/diagnóstico por imagen , Huesos Faciales/cirugía , Humanos , Radiólogos , Estudios Retrospectivos , Fracturas Craneales/diagnóstico por imagen , Fracturas Craneales/cirugía
11.
Head Neck ; 43(11): 3417-3428, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34409671

RESUMEN

BACKGROUND: Surgical site infections (SSI) are common complications of free-flap reconstruction for head and neck cancer defects. This study aimed to identify risk factors for SSI following a significant change in local antibiotic prophylaxis practice. METHODS: A retrospective cohort study was conducted of 325 patients receiving free-flap reconstruction for head and neck cancer defects at a tertiary hospital in Melbourne, Australia between 2013 and 2019. Charts were queried for recipient SSI (primary outcome), donor SSI, other infections, antibiotic use, hospital length of stay, and mortality. RESULTS: Risk factors for SSI included female sex, T-classification, hardware insertion, clindamycin prophylaxis, and operative duration. There was a trend toward increased SSI with shorter ≤24 h prophylaxis (OR: 0.43). CONCLUSION: Antibiotic duration and type were associated with SSI. Complexity of surgery, T-classification, hardware use, and operative duration were also independently associated with SSI. A prospective trial is indicated to elicit optimal prophylactic antibiotic duration.


Asunto(s)
Colgajos Tisulares Libres , Neoplasias de Cabeza y Cuello , Procedimientos de Cirugía Plástica , Profilaxis Antibiótica , Australia/epidemiología , Estudios de Cohortes , Femenino , Neoplasias de Cabeza y Cuello/cirugía , Humanos , Estudios Prospectivos , Estudios Retrospectivos , Factores de Riesgo , Infección de la Herida Quirúrgica/epidemiología , Infección de la Herida Quirúrgica/etiología , Infección de la Herida Quirúrgica/prevención & control
13.
J Plast Reconstr Aesthet Surg ; 72(9): 1465-1477, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31324403

RESUMEN

BACKGROUND: The traditional approach to head and neck reconstruction is considered challenging, requiring a subjective assessment of an often-complex defect followed by careful modelling of a bony flap to match this. The introduction of Virtual Surgical Planning (VSP) has provided the surgeon with a means to increase efficiency, precision and overall patient outcomes. This study aims to compare VSP and traditional head and neck reconstructions utilising fibula free flaps with regards surgical efficiency and patient outcomes. METHODS: A systematic search of the PubMed and Medline databases was performed from the date of their inception through to August 2018 to evaluate and compare VSP and non-VSP cohorts in the context of fibula free flap head and neck reconstruction. Primary comparative outcomes included operative and ischaemic time, with secondary outcomes including complications rates, measures of accuracy and financial benefits. RESULTS: One hundred and fifty-three articles were identified. Twenty-three articles were included in the review, comprising a total of 713 patients. VSP was associated with significantly decreased intraoperative time (Standardised Mean Difference -1.01; 95% CI -1.23 to 0.80; p = 0.000) and ischaemic time (Standardised Mean Difference -1.55; 95% CI -1.87 to -1.23, p = 0.002). VSP was also associated with reduced orthognathic deviation from an ideal outcome when compared to conventional techniques. No statistically significant differences in complication rates between conventional and VSP techniques were identified. CONCLUSION: The results of this meta-analysis suggests that VSP confers significant benefits with respect to improved orthognathic accuracy, ischaemic times and intraoperative times without any significant increase in complications. Recommendations for ongoing research are suggested.


Asunto(s)
Peroné/trasplante , Colgajos Tisulares Libres , Neoplasias de Cabeza y Cuello/cirugía , Planificación de Atención al Paciente , Procedimientos de Cirugía Plástica/métodos , Cirugía Asistida por Computador/métodos , Realidad Virtual , Humanos
14.
J Plast Reconstr Aesthet Surg ; 72(9): 1478-1483, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31204153

RESUMEN

BACKGROUND: Bony free flaps are used to reconstruct head and neck cancer defects. The most commonly used flaps are the free fibula flap and the deep circumflex iliac artery (DCIA) flap. Radiotherapy may be given post-operatively to prevent cancer recurrence. This radiotherapy can, however, destroy the bone; a complication termed osteoradionecrosis (ORN). Although there have been studies comparing free fibula and DCIA flaps in terms of success rates and complications, few have assessed the incidence of ORN in both groups. METHODS: A retrospective cohort study was conducted involving patients from Royal Melbourne Hospital and St Vincent's Hospital Melbourne who had either a free fibula or DCIA flap for head and neck cancer reconstruction in the past 10 years. Data collected included demographic, operative, and postoperative data. Analysis was performed using Statistical Package for Social Sciences and Microsoft Excel, utilising t-tests, chi-square tests and logistic regression analyses. RESULTS: A total of 154 patients were identified. Of these patients, 127 had free fibula flaps and 27 had free DCIA flaps. Twelve patients had ORN post-op, 10 had free fibula flaps, and 2 had free DCIA flaps. No statistically significant difference was found between the ORN rates in free fibula flaps and free DCIA flaps. CONCLUSION: Rates of ORN incidence should not be a major consideration in preoperative planning of free flaps for mandibular reconstruction as both fibula and DCIA free flaps are comparable.


Asunto(s)
Trasplante Óseo/métodos , Peroné/trasplante , Neoplasias de Cabeza y Cuello/cirugía , Arteria Ilíaca/trasplante , Mandíbula/efectos de la radiación , Reconstrucción Mandibular/métodos , Osteorradionecrosis/epidemiología , Femenino , Peroné/efectos de la radiación , Estudios de Seguimiento , Neoplasias de Cabeza y Cuello/radioterapia , Humanos , Incidencia , Masculino , Mandíbula/diagnóstico por imagen , Mandíbula/cirugía , Persona de Mediana Edad , Osteorradionecrosis/diagnóstico , Osteorradionecrosis/etiología , Radiografía Panorámica , Radioterapia Adyuvante/efectos adversos , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Victoria/epidemiología
16.
Cardiovasc Ther ; 35(1): 64-70, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27790832

RESUMEN

Platelet activating factor (PAF) is a potent pro-inflammatory negotiator that shows distinct spectrum of biological and pharmacological effects. Importantly, it participates in a wide range of pathophysiological conditions. In cardiovascular system, PAF has been shown to have an important role in platelet and neutrophil aggregation, vascular permeability, microvascular leakage, thrombus formation, leukocyte adhesion to the endothelial cells, and initiation and progression of atherosclerosis. The purpose of this article was to review the PAF, a family of lipids that is associated with the pathology of coronary artery diseases due to their association with leading etiological mechanisms such as inflammation, endothelial dysfunction, oxidative and nitrosative stress, and platelet reactivity. This review further provides information about PAF and its potential role as a key contributor to the pathogenesis of cardiovascular disorders.


Asunto(s)
Síndrome Coronario Agudo/sangre , Plaquetas/metabolismo , Mediadores de Inflamación/sangre , Factor de Activación Plaquetaria/metabolismo , Activación Plaquetaria , Síndrome Coronario Agudo/diagnóstico , Animales , Biomarcadores/sangre , Humanos , Valor Predictivo de las Pruebas , Pronóstico , Transducción de Señal
17.
J Biol Methods ; 2(2)2015.
Artículo en Inglés | MEDLINE | ID: mdl-26280010

RESUMEN

The use of small molecules to interfere with protein-protein interactions has tremendous therapeutic appeal and is an area of intense interest. Numerous techniques exist to assess these interactions and their disruption. Many, however, require large amounts of protein, do not allow interactions to be followed in real time, are technically demanding or require large capital expenditures and high levels of expertise. Surface plasmon resonance (SPR) represents a convenient alternative to these techniques with virtually none of their disadvantages. We have devised an SPR-based method that allows the heterodimeric association between the c-Myc (Myc) oncoprotein and its obligate partner Max to be quantified in a manner that agrees well with values obtained by other methods. We have adapted it to examine the ability of previously validated small molecules to interfere with Myc-Max heterodimerization and DNA binding. These inhibitors comprised two distinct classes of molecules that inhibit DNA binding by preventing Myc-Max interaction or distorting pre-formed heterodimers and rendering them incapable of DNA binding. Our studies also point out several potential artifacts and pitfalls to be considered when attempting to employ similar SPR-based methods. This technique should be readily adaptable to the study of other protein-protein interactions and their disruption by small molecules.

18.
Biosens Bioelectron ; 18(4): 399-404, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12604257

RESUMEN

The use of biosensors for monitoring real time interactions between biomolecules and drug compounds has a lot of advantages over presently existing detection methods, the major ones being the elimination of radio labels and rapid screening. We can also obtain information about the kinetic parameters and these values may serve as useful indicators towards subtle differences in the binding strength and characteristics of closely related drug compounds and enantiomers. The Biacore 3000 biosensor based on the Surface Plasmon Resonance (SPR) technology was used to assess the albumin protein binding differences between two enantiomers of a drug compound. Normalized responses (NRU) and affinity constants (K(D)) were readily calculated. Statistical parameters like mean normalized responses, %CV values were determined to make the technique robust. The %CV values obtained were within the preset limits of < or = 25% (FDA limits for drug development and method validation protocols) for the binding interactions for majority of the concentrations studied. For example, the %CV values for the normalized responses for the binding of the control drug warfarin to human albumin ranged from 7.9 to 24.3%. The method gave reproducible results, and the results indicated slight differences in binding patterns of the enantiomers to human and rat albumin.


Asunto(s)
Técnicas Biosensibles/instrumentación , Técnicas Biosensibles/métodos , Preparaciones Farmacéuticas/química , Preparaciones Farmacéuticas/clasificación , Albúmina Sérica/química , Resonancia por Plasmón de Superficie/instrumentación , Resonancia por Plasmón de Superficie/métodos , Animales , Estudios de Factibilidad , Humanos , Isomerismo , Sustancias Macromoleculares , Preparaciones Farmacéuticas/análisis , Unión Proteica , Ratas , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
19.
Arch Med Res ; 34(6): 565-71, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-14734097

RESUMEN

It has become clear that adult mammalian bone marrow contains not one but two ostensibly discrete populations of adult stem cells. The first and by far the most fully characterized are the hematopoietic stem cells responsible for maintaining lifelong production of blood cells. The biological characteristics and properties of the second marrow resident population of stem cells, variously termed bone marrow stromal cells or mesenchymal stem cells, are in contrast much less well understood. In vitro, cultures established from single-cell suspensions of bone marrow from a wide range of mammalian species generate colonies of adherent marrow stromal cells, each derived from a single precursor cell termed a colony-forming unit-fibroblast (CFU-F). Culture conditions have been developed to expand marrow stromal cells in vitro while maintaining the capacity of these cells to differentiate into bone, fat, and cartilage. A significant portion of our current knowledge of this population of cells is based on analysis of the properties of these culture expanded cells, not on the primary colony-initiating cells. In this article, we will focus on methodologies to prospectively isolate stromal progenitors from mouse and human bone marrow and will review current data that suggest stromal progenitors in the bone marrow in situ are associated with the outer surfaces of blood vessels and may share identity with vascular pericytes.


Asunto(s)
Células de la Médula Ósea/fisiología , Células Madre Hematopoyéticas/fisiología , Mesodermo/citología , Células del Estroma/fisiología , Animales , Humanos , Fenotipo
20.
Biosystems ; 66(3): 165-77, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12413747

RESUMEN

A fractal analysis of DNA binding and dissociation kinetics on biosensor surfaces is presented. The fractal approach provides an attractive, convenient method to model the kinetic data taking into account the effects of surface heterogeneity brought about by ligand immobilization. The fractal technique can be used in conjunction or as an alternate approach to conventional modeling techniques, such as the Langmuir model, saturation model, etc. Examples analyzed include a DNA molecular beacon biosensor and a plasmid DNA-(cationic polymer) interaction biosensor. The molecular beacon example provides some insights into the nature of the surface and how it influences the binding rate coefficients. The DNA-cationic polymer interaction example provides some quantitative results on the binding and dissociation rate coefficients. Data taken from the literature may be modeled, in the case of binding, using a single-fractal analysis or a dual-fractal analysis. The dual-fractal analysis results indicate a change in the binding mechanism as the reaction progresses on the surface. A single-fractal analysis is adequate to model the dissociation kinetics in the example presented. Relationships are presented for the binding rate coefficients as a function of their corresponding fractal dimension, D(f), which is an indication of the degree of heterogeneity that exists on the surface. When analyte-receptor binding is involved, an increase in the heterogeneity of the surface (increase in D(f)) leads to an increase in the binding rate coefficient.


Asunto(s)
Técnicas Biosensibles , ADN , Fractales , Técnicas Biosensibles/estadística & datos numéricos , ADN/metabolismo , Técnicas In Vitro , Cinética , Modelos Teóricos , Plásmidos/metabolismo
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