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1.
J Surg Res ; 302: 798-804, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39226704

RESUMO

INTRODUCTION: Tranexamic acid (TXA) is an antifibrinolytic drug that has been demonstrated to reduce head injury-related mortality when given within 2 h of injury in patients with traumatic brain injury and intracranial hemorrhage. It is usually administered via intravenous (IV) access, which can be difficult to obtain in prehospital and austere settings. Intraosseous (IO) access is fast and offers an alternative when IV access proves challenging; however, TXA administration via IO access has never been studied in humans. We sought to determine if the total drug exposure of TXA given in the prehospital setting in patients with moderate or severe brain injury differs based on route of administration. METHODS: We performed a retrospective analysis of prospectively collected data from the prehospital TXA for traumatic brain injury trial (NCT01990768). Participants who received TXA via IO administration were compared to those who received TXA via IV administration and stratified by renal function category based on the Kidney Disease Improving Global Outcomes criteria. The area under the plasma drug concentration-time curve (AUC) was calculated using the trapezoidal rule (Phoenix WinNonlin 8.3, Certara, Princeton NJ) to obtain total drug exposure. The inverse variance method was used to combine observations within strata and calculate mean differences. RESULTS: Of the 966 participants enrolled in the trial, 345 participants received a 2-g TXA prehospital bolus (11 IO, 334 IV); 312 participants received a 1-g TXA prehospital bolus followed by a 1-g TXA infusion in-hospital over 8 h (13 IO, 299 IV). After exclusion because of missing data and extreme estimated AUC, 233 IV and eight IO participants in the 2-g bolus arm and 152 IV and eight IO participants in the 1-g bolus 1-g infusion arm remained. Participants did not differ by age, sex, race, ethnicity, body mass index, serum creatinine, estimated glomerular filtration rate, or clot lysis at 30 min on thromboelastography. No difference in the mean AUCs were observed between IV and IO for either the 2-g bolus group (-2.6 µ g/mL/h [IO] compared to IV, 95% confidence interval: -28.4 to 23.3 µ g/mL/h) or the 1-g bolus/1-g infusion group (-13.0 µ g/mL/h [IO] compared to IV, 95% confidence interval: -236.2 to 210.3 µ g/mL/h). CONCLUSIONS: These preliminary data suggest that the administration of TXA via IO and IV routes may result in similar total drug exposure. Further studies incorporating larger numbers with clinical outcomes are needed to confirm this finding.


Assuntos
Antifibrinolíticos , Lesões Encefálicas Traumáticas , Infusões Intraósseas , Ácido Tranexâmico , Humanos , Ácido Tranexâmico/administração & dosagem , Antifibrinolíticos/administração & dosagem , Masculino , Estudos Retrospectivos , Feminino , Lesões Encefálicas Traumáticas/tratamento farmacológico , Adulto , Pessoa de Meia-Idade , Infusões Intravenosas , Administração Intravenosa , Resultado do Tratamento , Adulto Jovem , Serviços Médicos de Emergência/métodos
2.
JAMA Netw Open ; 7(9): e2431115, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39230905

RESUMO

Importance: Data on the performance of traumatic brain injury (TBI) biomarkers within minutes of injury are lacking. Objectives: To examine the performance of glial fibrillary acidic protein (GFAP), ubiquitin carboxy-terminal hydrolase L1 (UCH-L1), and microtubule-associated protein 2 (MAP-2) within 30 and 60 minutes of TBI in identifying intracranial lesions on computed tomography (CT) scan, need for neurosurgical intervention (NSI), and clinically important early outcomes (CIEO). Design, Setting, and Participants: This cohort study is a biomarker analysis of a multicenter prehospital TBI cohort from the Prehospital Tranexamic Acid Use for TBI clinical trial conducted across 20 centers and 39 emergency medical systems in North America from May 2015 to March 2017. Prehospital hemodynamically stable adult patients with traumatic injury and suspected moderate to severe TBI were included. Blood samples were measured for GFAP, UCH-L1, and MAP-2. Data were analyzed from December 1, 2023, to March 15, 2024. Main Outcomes and Measures: The presence of CT lesions, diffuse injury severity on CT, NSI within 24 hours of injury, and CIEO (composite outcome including early death, neurosurgery, or prolonged mechanical ventilation ≥7 days) within 7 days of injury. Results: Of 966 patients enrolled, 804 patients (mean [SD] age, 41 [19] years; 418 [74.2%] male) had blood samples, including 563 within 60 minutes and 375 within 30 minutes of injury. Among patients with blood drawn within 30 minutes of injury, 212 patients (56.5%) had CT lesions, 61 patients (16.3%) had NSI, and 112 patients (30.0%) had CIEO. Among those with blood drawn within 60 minutes, 316 patients (56.1%) had CT lesions, 95 patients (16.9%) had NSI, and 172 patients (30.6%) had CIEO. All biomarkers showed significant elevations with worsening diffuse injury on CT within 30 and 60 minutes of injury. Among blood samples taken within 30 minutes, GFAP had the highest area under the receiver operating characteristic curve (AUC) to detect CT lesions, at 0.88 (95% CI, 0.85-0.92), followed by MAP-2 (AUC, 0.78; 95% CI, 0.73-0.83) and UCH-L1 (AUC, 0.75; 95% CI, 0.70-0.80). Among blood samples taken within 60 minutes, AUCs for CT lesions were 0.89 (95% CI, 0.86-0.92) for GFAP, 0.76 (95% CI, 0.72-0.80) for MAP-2, and 0.73 (95% CI, 0.69-0.77) for UCH-L1. Among blood samples taken within 30 minutes, AUCs for NSI were 0.78 (95% CI, 0.72-0.84) for GFAP, 0.75 (95% CI, 0.68-0.81) for MAP-2, and 0.69 (95% CI, 0.63-0.75) for UCH-L1; and for CIEO, AUCs were 0.89 (95% CI, 0.85-0.93) for GFAP, 0.83 (95% CI, 0.78-0.87) for MAP-2, and 0.77 (95% CI, 0.72-0.82) for UCH-L1. Combining the biomarkers was no better than GFAP alone for all outcomes. At GFAP of 30 pg/mL within 30 minutes, sensitivity for CT lesions was 98.1% (95% CI, 94.9%-99.4%) and specificity was 34.4% (95% CI, 27.2%-42.2%). GFAP levels greater than 6200 pg/mL were associated with high risk of NSI and CIEO. Conclusions and Relevance: In this cohort study of prehospital patients with TBI, GFAP, UCH-L1, and MAP-2 measured within 30 and 60 minutes of injury were significantly associated with traumatic intracranial lesions and diffuse injury severity on CT scan, 24-hour NSI, and 7-day CIEO. GFAP was the strongest independent marker associated with all outcomes. This study sets a precedent for the early utility of GFAP in the first 30 minutes from injury in future clinical and research endeavors.


Assuntos
Biomarcadores , Lesões Encefálicas Traumáticas , Proteína Glial Fibrilar Ácida , Proteínas Associadas aos Microtúbulos , Ubiquitina Tiolesterase , Humanos , Lesões Encefálicas Traumáticas/sangue , Ubiquitina Tiolesterase/sangue , Masculino , Feminino , Adulto , Proteína Glial Fibrilar Ácida/sangue , Pessoa de Meia-Idade , Biomarcadores/sangue , Proteínas Associadas aos Microtúbulos/sangue , Tomografia Computadorizada por Raios X , Estudos de Coortes , Fatores de Tempo
3.
Nat Commun ; 15(1): 7461, 2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39198422

RESUMO

Anti-HIV-1 broadly neutralizing antibodies (bNAbs) have the dual potential of mediating virus neutralization and antiviral effector functions through their Fab and Fc domains, respectively. So far, bNAbs with enhanced Fc effector functions in vitro have only been tested in NHPs during chronic simian-HIV (SHIV) infection. Here, we investigate the effects of administering in acute SHIVAD8-EO infection either wild-type (WT) bNAbs or bNAbs carrying the S239D/I332E/A330L (DEL) mutation, which increases binding to FcγRs. Emergence of virus in plasma and lymph nodes (LNs) was delayed by bNAb treatment and occurred earlier in monkeys given DEL bNAbs than in those given WT bNAbs, consistent with faster clearance of DEL bNAbs from plasma. DEL bNAb-treated monkeys had higher levels of circulating virus-specific IFNγ single-producing CD8+ CD69+ T cells than the other groups. In LNs, WT bNAbs were evenly distributed between follicular and extrafollicular areas, but DEL bNAbs predominated in the latter. At week 8 post-challenge, LN monocytes and NK cells from DEL bNAb-treated monkeys upregulated proinflammatory signaling pathways and LN T cells downregulated TNF signaling via NF-κB. Overall, bNAbs with increased affinity to FcγRs shape innate and adaptive cellular immunity, which may be important to consider in future strategies of passive bNAb therapy.


Assuntos
Anticorpos Neutralizantes , Anticorpos Anti-HIV , HIV-1 , Macaca mulatta , Receptores de IgG , Síndrome de Imunodeficiência Adquirida dos Símios , Vírus da Imunodeficiência Símia , Animais , Receptores de IgG/imunologia , Receptores de IgG/metabolismo , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , HIV-1/imunologia , Vírus da Imunodeficiência Símia/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Anti-HIV/imunologia , Anticorpos Monoclonais/imunologia , Linfonodos/imunologia , Linfócitos T CD8-Positivos/imunologia , Afinidade de Anticorpos/imunologia , NF-kappa B/metabolismo , NF-kappa B/imunologia , Humanos , Infecções por HIV/imunologia , Infecções por HIV/virologia , Células Matadoras Naturais/imunologia , Anticorpos Amplamente Neutralizantes/imunologia
4.
Eur J Cancer ; 201: 113950, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38422585

RESUMO

BACKGROUND: There is no standard of care for ≥ 3rd-line treatment of metastatic pancreatic adenocarcinoma (PDAC). CBP501 is a novel calmodulin-binding peptide that has been shown to enhance the influx of platinum agents into tumor cells and tumor immunogenicity. This study aimed to (1) confirm efficacy of CBP501/cisplatin/nivolumab for metastatic PDAC observed in a previous phase 1 study, (2) identify combinations that yield 35% 3-month progression-free survival rate (3MPFS) and (3) define the contribution of CBP501 to the effects of combination therapy. METHODS: CBP501 16 or 25 mg/m2 (CBP(16) or CBP(25)) was combined with 60 mg/m2 cisplatin (CDDP) and 240 mg nivolumab (nivo), administered at 3-week intervals. Patients were randomized 1:1:1:1 to (1) CBP(25)/CDDP/nivo, (2) CBP(16)/CDDP/nivo, (3) CBP(25)/CDDP and (4) CDDP/nivo, with randomization stratified by ECOG PS and liver metastases. A Fleming two-stage design was used, yielding a one-sided type I error rate of 2.5% and 80% power when the true 3MPFS is 35%. RESULTS: Among 36 patients, 3MPFS was 44.4% in arms 1 and 2, 11.1% in arm 3% and 33.3% in arm 4. Two patients achieved a partial response in arm 1 (ORR 22.2%; none in other arms). Median PFS and OS were 2.4, 2.1, 1.5 and 1.5 months and 6.3, 5.3, 3.7 and 4.9 months, respectively. Overall, all treatment combinations were well tolerated. Most treatment-related adverse events were grade 1-2. CONCLUSIONS: The combination CBP(25)/(16)/CDDP/nivo demonstrated promising signs of efficacy and a manageable safety profile for the treatment of advanced PDAC. CLINICAL TRIAL REGISTRATION: NCT04953962.


Assuntos
Adenocarcinoma , Neoplasias Pancreáticas , Fragmentos de Peptídeos , Fosfatases cdc25 , Humanos , Cisplatino , Adenocarcinoma/patologia , Nivolumabe/efeitos adversos , Neoplasias Pancreáticas/patologia , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos
5.
ACS Appl Bio Mater ; 7(2): 1052-1063, 2024 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-38290529

RESUMO

Intracortical microelectrode arrays (MEAs) are used for recording neural signals. However, indwelling devices result in chronic neuroinflammation, which leads to decreased recording performance through degradation of the device and surrounding tissue. Coating the MEAs with bioactive molecules is being explored to mitigate neuroinflammation. Such approaches often require an intermediate functionalization step such as (3-aminopropyl)triethoxysilane (APTES), which serves as a linker. However, the standalone effect of this intermediate step has not been previously characterized. Here, we investigated the effect of coating MEAs with APTES by comparing APTES-coated to uncoated controls in vivo and ex vivo. First, we measured water contact angles between silicon uncoated and APTES-coated substrates to verify the hydrophilic characteristics of the APTES coating. Next, we implanted MEAs in the motor cortex (M1) of Sprague-Dawley rats with uncoated or APTES-coated devices. We assessed changes in the electrochemical impedance and neural recording performance over a chronic implantation period of 16 weeks. Additionally, histology and bulk gene expression were analyzed to understand further the reactive tissue changes arising from the coating. Results showed that APTES increased the hydrophilicity of the devices and decreased electrochemical impedance at 1 kHz. APTES coatings proved detrimental to the recording performance, as shown by a constant decay up to 16 weeks postimplantation. Bulk gene analysis showed differential changes in gene expression between groups that were inconclusive with regard to the long-term effect on neuronal tissue. Together, these results suggest that APTES coatings are ultimately detrimental to chronic neural recordings. Furthermore, interpretations of studies using APTES as a functionalization step should consider the potential consequences if the final functionalization step is incomplete.


Assuntos
Aminas , Doenças Neuroinflamatórias , Ratos , Animais , Ratos Sprague-Dawley , Microeletrodos , Eletrodos Implantados , Materiais Revestidos Biocompatíveis/química
6.
Aust Vet J ; 102(4): 200-214, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38220215

RESUMO

We quantified the sensitivity of surveillance for lumpy skin disease (LSD) and foot and mouth disease (FMD) in cattle in the Kimberley region of Western Australia. We monitored producer and veterinary activity with cattle for 3 years commencing January 2020. Each year, ~274,000 cattle of 685,540 present on 92 pastoral leases (stations) were consigned to other stations, live export or slaughter. Veterinarians examined 103,000 cattle on the stations, 177,000 prior to live export, and 10,000 prior to slaughter. Detection probabilities for the disease prior to transport or during veterinary procedures and inspections were elicited by survey of 17 veterinarians working in Northern Australia. The veterinarians estimated the probabilities that they would notice, recognise, and submit samples from clinical cases of LSD and FMD, given a 5% prevalence of clinical signs in the herd. We used scenario tree methodology to estimate monthly surveillance sensitivity of observations made by producers and by veterinarians during herd management visits, pre-export inspections, and ante-mortem inspections. Average monthly combined sensitivities were 0.49 for FMD and 0.37 for LSD. Sensitivity was high for both diseases during the dry season and low in the wet season. We estimated the confidence in freedom from the estimated surveillance sensitivity given one hypothetically infected herd, estimated probability of introduction, and prior confidence in freedom. This study provided assurance that the Kimberley is free of these diseases and that routine producer and veterinary interactions with cattle are adequate for the timely detection of the disease should they be introduced.


Assuntos
Doenças dos Bovinos , Febre Aftosa , Doença Nodular Cutânea , Animais , Bovinos , Febre Aftosa/diagnóstico , Febre Aftosa/epidemiologia , Austrália Ocidental/epidemiologia , Doença Nodular Cutânea/diagnóstico , Doença Nodular Cutânea/epidemiologia , Surtos de Doenças/veterinária , Austrália/epidemiologia , Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/epidemiologia
7.
J Neurol Phys Ther ; 48(2): 83-93, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37436187

RESUMO

BACKGROUND AND PURPOSE: Aerobic exercise can elicit positive effects on neuroplasticity and cognitive executive function but is poorly understood after stroke. We tested the effect of 4 weeks of aerobic exercise training on inhibitory and facilitatory elements of cognitive executive function and electroencephalography markers of cortical inhibition and facilitation. We investigated relationships between stimulus-evoked cortical responses, blood lactate levels during training, and aerobic fitness postintervention. METHODS: Twelve individuals with chronic (>6 months) stroke completed an aerobic exercise intervention (40 minutes, 3×/wk). Electroencephalography and motor response times were assessed during congruent (response facilitation) and incongruent (response inhibition) stimuli of a Flanker task. Aerobic fitness capacity was assessed as o2peak during a treadmill test pre- and postintervention. Blood lactate was assessed acutely (<1 minute) after exercise each week. Cortical inhibition (N2) and facilitation (frontal P3) were quantified as peak amplitudes and latencies of stimulus-evoked electroencephalographic activity over the frontal cortical region. RESULTS: Following exercise training, the response inhibition speed increased while response facilitation remained unchanged. A relationship between earlier cortical N2 response and faster response inhibition emerged postintervention. Individuals who produced higher lactate during exercise training achieved faster response inhibition and tended to show earlier cortical N2 responses postintervention. There were no associations between o2peak and metrics of behavioral or neurophysiologic function. DISCUSSION AND CONCLUSIONS: These preliminary findings provide novel evidence for selective benefits of aerobic exercise on inhibitory control during the initial 4-week period after initiation of exercise training and implicate a potential therapeutic effect of lactate on poststroke inhibitory control.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Humanos , Terapia por Exercício , Exercício Físico/fisiologia , Lactatos
10.
J Eur Acad Dermatol Venereol ; 35(7): 1543-1552, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33834521

RESUMO

BACKGROUND: Baricitinib is an oral, selective, reversible Janus kinase 1/2 inhibitor approved in the European Union and Japan and under investigation in the United States for treatment of atopic dermatitis (AD). OBJECTIVES: To evaluate the impact of baricitinib plus background topical corticosteroids (TCS) on health-related quality of life (HRQoL), how AD symptoms impact work productivity and life functioning, and treatment benefit using patient-reported outcome (PRO) assessments in patients with moderate-to-severe AD previously experiencing inadequate response to TCS. METHODS: Adult patients with AD in BREEZE-AD7, a Phase 3, multicentre, double-blind trial, were randomised 1 : 1 : 1 to daily oral placebo (control) or baricitinib 4- or 2-mg plus TCS. PROs reported Week 1 through Week 16: Dermatology Life Quality Index (DLQI), Work Productivity and Activity Impairment-AD (WPAI-AD); Patient-Reported Outcomes Measurement Information System (PROMIS) Itch and Sleep measures, and Patient Benefit Index (PBI). Data were analysed using logistic regression (categorical) and mixed model repeated measures (continuous). PBI scores were analysed using analysis of variance. RESULTS: A total of 329 patients were randomised. Treatment with baricitinib 4-mg (N = 111) or 2 mg (N = 109) plus TCS led to rapid, statistically significant improvements [vs. TCS plus placebo (N = 109)] in DLQI ≥4-point improvement starting at Week 2 (4-mg plus TCS, P ≤ 0.001; 2-mg plus TCS P ≤ 0.05), change from baseline in WPAI-AD presenteeism at Week 1 (4-mg plus TCS, P ≤ 0.01; 2-mg plus TCS P ≤ 0.05) and PROMIS itch interference at Week 2 (4-mg plus TCS P ≤ 0.01). Improvements were sustained through Week 16 for baricitinib 4-mg. Statistically significant improvements were observed at Week 16 for PBI global score (4-mg plus TCS, P ≤ 0.001; 2-mg plus TCS P ≤ 0.05). CONCLUSIONS: Baricitinib plus TCS vs. placebo plus TCS showed significant improvements in treatment benefit at Week 16 and rapid significant improvements in HRQoL and impact of AD symptoms on work productivity and functioning through 16 weeks.


Assuntos
Dermatite Atópica , Qualidade de Vida , Adulto , Azetidinas , Dermatite Atópica/tratamento farmacológico , Método Duplo-Cego , Humanos , Japão , Purinas , Pirazóis , Índice de Gravidade de Doença , Esteroides , Sulfonamidas , Resultado do Tratamento
11.
Obes Rev ; 18 Suppl 2: 28-38, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28741904

RESUMO

BACKGROUND: Addressing childhood obesity in Latin America requires a package of multisectoral, evidence-based policies that enable environments conducive to healthy lifestyles. OBJECTIVE: Identify and examine key elements to translating research into effective obesity policies in Latin America. METHODS: We examined obesity prevention policies through case studies developed with an expert in the specific policy. Policies were selected based on their level of implementation, visibility and potential impact to reduce childhood obesity. They include: (i) excise taxes on sugar sweetened beverages and energy-dense foods; (ii) front-of-package food label legislation; (iii) trans fatty acids removal from processed foods; and (iv) Ciclovías recreativas or 'open streets'. Case studies were coded to identify components that explained successful implementation and sustainability using the Complex Adaptive Health Systems framework. RESULTS: The analysis identified key elements for effective and sustainable policy, including evidence justifying policy; evidence-based advocacy by civil society; political will; and legislation and skillful negotiations across government, academia, the private sector and civil society. Scientific evidence and evaluation played an important role in achieving tipping points for policies' launch and sustain effective implementation. CONCLUSIONS: Well-coordinated, intersectoral partnerships are needed to successfully implement evidence-based anti-obesity policies. Prospective policy research may be useful for advancing knowledge translation.


Assuntos
Rotulagem de Alimentos , Programas Governamentais , Política Nutricional , Obesidade Infantil/prevenção & controle , Bebidas , Criança , Humanos , América Latina , Estudos Prospectivos , Edulcorantes , Impostos
12.
Ergonomics ; 57(5): 679-92, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24646414

RESUMO

This study assesses lateral tipping motion-induced interruptions (MIIs) in a simulated motion environment. The objective is to revisit MII occurrence and sway motion relationship by focusing on the frequency and acceleration of the lateral motion stimulus. Results verify that MIIs increase with increasing peak sway acceleration, but the effect of sway frequency is not as clear as that of acceleration. Complex multidirectional motions create more tipping MIIs than unidirectional motion. Research should incorporate acceleration, frequency and motion complexity as factors influencing MII occurrence. To describe a temporary loss of balance without tipping, the term 'probable' MII is introduced. This term fills the gap between the theoretical definition and a human-centred perception of an MII where loss of balance is not a binary phenomenon. The 'probable' MIIs were 16-67% more common than the 'definite' MIIs. The developed mathematical model of MII occurrence versus sway acceleration (amplitude, frequency) approximated the observed MIIs with less than 9% difference.


Assuntos
Aceleração , Movimento (Física) , Equilíbrio Postural/fisiologia , Feminino , Humanos , Masculino , Modelos Teóricos , Medicina Naval , Propriocepção , Navios
15.
Instr Course Lect ; 59: 387-404, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20415394

RESUMO

When conservative treatment is unsuccessful, there are many surgical options to treat patients with symptomatic chronic osteochondral lesions of the talus. The chosen treatment depends on the patient's symptoms, clinical examination findings, preoperative imaging results, and whether prior surgery was unsuccessful. It is important to be aware of treatment alternatives such as marrow stimulation, osteochondral autograft or allograft plugs, autologous chondrocyte implantation, and newer techniques currently being investigated outside the United States.


Assuntos
Articulação do Tornozelo , Cistos Ósseos/cirurgia , Cartilagem Articular , Artropatias/cirurgia , Osteocondrite/cirurgia , Tálus , Artroscopia , Cistos Ósseos/diagnóstico por imagem , Cistos Ósseos/patologia , Transplante Ósseo , Condrócitos/transplante , Humanos , Artropatias/diagnóstico por imagem , Artropatias/patologia , Osteocondrite/diagnóstico por imagem , Osteocondrite/patologia , Seleção de Pacientes , Radiografia , Suporte de Carga
16.
Cell Biochem Biophys ; 55(2): 107-16, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19639425

RESUMO

The standard codon table is a primary tool for basic understanding of molecular biology. In the minds of many, the table's orderly arrangement of bases and amino acids is synonymous with the true genetic code, i.e., the biological coding principle itself. However, developments in the field reveal a much more complex and interesting picture. In this article, we review the traditional codon table and its limitations in light of the true complexity of the genetic code. We suggest the codon table be brought up to date and, as a step, we present a novel superposition of the BLOSUM62 matrix and an allowed point mutation matrix. This superposition depicts an important aspect of the true genetic code-its ability to tolerate mutations and mistranslations.


Assuntos
Código Genético , Algoritmos , Aminoácidos/genética , Humanos , Mutação
17.
Langmuir ; 25(11): 6143-54, 2009 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-19408902

RESUMO

The shortcomings of the current formulation for calculating the adhesion force for drops and bubbles with noncircular contact lines are discussed. A general formulation to evaluate the adhesion force due to surface forces is presented. Also, a novel methodology, that is, IBAFA, image based adhesion force analysis, was developed to allow implementation of the general formulation. IBAFA is based on the use of multiple profile images of a drop. The images are analyzed (1) to accurately reconstruct the contact line shape, which is analytically represented by a Fourier cosine series, and (2) to measure contact angles at multiple locations along the contact line and determine the contact angle distribution based on a linear piecewise interpolation routine. The contact line shape reconstruction procedure was validated with both actual experiments and simulated experiments. The procedure for the evaluation of the adhesion force was tested using simulated experiments with synthetic drops of known shapes. A comparison with current methods showed that simplifying assumptions (e.g., elliptical contact line or linear contact angle distribution) used in these methods result in errors up to 76% in the estimated adhesion force. However, the drop adhesion force evaluated using IBAFA results in small errors on the order of 1%.

18.
Foot Ankle Int ; 30(4): 341-5, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19356359

RESUMO

BACKGROUND: The Lapidus bunionectomy is a popular procedure for severe bunion deformity where metatarsus primus varus is equal to or exceeds 15 degrees. We evaluated a new locking compression plate which may improve outcomes with the Lapidus procedure. METHODS: Ten matched pairs of cadaver feet were used to compare the standard crossed 4.0-mm compression screw method of fixation to the LPS Lapidus plate. After performing the matched operations the cadaver constructs were stressed to failure using the INSTRON and Wavemaker software. RESULTS: The LPS Lapidus plate load to failure was 108 Nm with a bending moment of 6.0 Nm. The crossed screw technique was inferior at 78 Nm with a bending moment of 4.4 Nm (p = 0.02) CONCLUSION: Unlike other H-plates or locking plates, load to failure was higher with the Lapidus plate constructs. CLINICAL RELEVANCE: The increased rigidity provided by these plates may help to minimize the risk of nonunion or malunion.


Assuntos
Artrodese/instrumentação , Placas Ósseas , Articulações do Pé , Hallux Valgus/cirurgia , Parafusos Ósseos , Cadáver , Análise de Falha de Equipamento , Humanos , Desenho de Prótese , Amplitude de Movimento Articular , Suporte de Carga
20.
Gene Ther ; 15(14): 1035-48, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18337839

RESUMO

Synthetic oligodeoxynucleotides (ODNs) had been employed in gene modification and represent an alternative approach to 'cure' genetic disorders caused by mutations. To test the ability of ODN-mediated gene repair in bone marrow-derived mesenchymal stem cells (MSCs), we established MSCs cell lines with stably integrated mutant neomycin resistance and enhanced green fluorescent protein reporter genes. The established cultures showed morphologically homogenous population with phenotypic and functional features of mesenchymal progenitors. Transfection with gene-specific ODNs successfully repaired targeted cells resulting in the expression of functional proteins at relatively high frequency approaching 0.2%. Direct DNA sequencing confirmed that phenotype change resulted from the designated nucleotide correction at the target site. The position of the mismatch-forming nucleotide was shown to be important structural feature for ODN repair activity. The genetically corrected MSCs were healthy and maintained an undifferentiated state. Furthermore, the genetically modified MSCs were able to engraft into many tissues of unconditioned transgenic mice making them an attractive therapeutic tool in a wide range of clinical applications.


Assuntos
DNA de Cadeia Simples/administração & dosagem , Resistência Microbiana a Medicamentos/genética , Terapia Genética/métodos , Células-Tronco Mesenquimais/metabolismo , Mutação , Reparo Gênico Alvo-Dirigido , Animais , Sequência de Bases , Técnicas de Cultura de Células , Expressão Gênica , Proteínas de Fluorescência Verde/genética , Transplante de Células-Tronco Mesenquimais , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microscopia Confocal , Microscopia de Fluorescência , Dados de Sequência Molecular , Transfecção/métodos
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