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A promising approach to study condensed-matter systems is to simulate them on an engineered quantum platform1-4. However, the accuracy needed to outperform classical methods has not been achieved so far. Here, using 18 superconducting qubits, we provide an experimental blueprint for an accurate condensed-matter simulator and demonstrate how to investigate fundamental electronic properties. We benchmark the underlying method by reconstructing the single-particle band structure of a one-dimensional wire. We demonstrate nearly complete mitigation of decoherence and readout errors, and measure the energy eigenvalues of this wire with an error of approximately 0.01 rad, whereas typical energy scales are of the order of 1 rad. Insight into the fidelity of this algorithm is gained by highlighting the robust properties of a Fourier transform, including the ability to resolve eigenenergies with a statistical uncertainty of 10-4 rad. We also synthesize magnetic flux and disordered local potentials, which are two key tenets of a condensed-matter system. When sweeping the magnetic flux we observe avoided level crossings in the spectrum, providing a detailed fingerprint of the spatial distribution of local disorder. By combining these methods we reconstruct electronic properties of the eigenstates, observing persistent currents and a strong suppression of conductance with added disorder. Our work describes an accurate method for quantum simulation5,6 and paves the way to study new quantum materials with superconducting qubits.
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PURPOSE: Despite previous studies proposing shorter durations of anti-HER2 therapy for selected patients with HER2-positive early breast cancer (EBC), 12-months remains standard of care. A survey was performed to assess patient perspectives and willingness to participate in studies evaluating shorter durations of anti-HER2 therapy. METHODS: Patients with HER2-positive EBC completing or having previously completed anti-HER2 therapy, were recruited by healthcare professionals at The Ottawa Hospital Cancer Centre to participate in an anonymous online survey. The primary objective was to learn about patients' perspectives on shorter durations (less than 12-months) of anti-HER2 therapy. Secondary objectives were to explore patients' interest in clinical trials of shorter durations of anti-HER2 therapy and the degree of increased breast cancer risk they would accept with a shorter treatment duration. RESULTS: Responses were received from 94 eligible patients. Most patients received Trastuzumab alone (78%, 73/94), while 13% (12/94) received trastuzumab and pertuzumab. Side effects were experienced by 52% (46/89), the most common being; fatigue (61%, 28/46), myalgia (37%, 17/46), and diarrhea (24%, 11/46). Most patients (88%, 78/89) did not find treatment bothersome. Regarding perspectives on shorter durations of anti-HER2 therapy, most (79%, 74/94) respondents stated they would agree to less treatment if it were possible to receive fewer treatments with the same cancer benefits. 56% of patients were interested in clinical trials, however, about half stated they would not be accepting of any increase in breast cancer recurrence risk. CONCLUSION: Trials to investigate who can safely and effectively be treated with shorter durations of anti-HER2 therapy are needed. This study provides important insights to patients' perspectives on shorter durations of anti-HER2 treatment, and their concerns regarding potential increased cancer risk with less treatment.
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Neoplasias de la Mama , Receptor ErbB-2 , Humanos , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Femenino , Receptor ErbB-2/metabolismo , Persona de Mediana Edad , Anciano , Adulto , Encuestas y Cuestionarios , Trastuzumab/uso terapéutico , Estadificación de Neoplasias , Anticuerpos Monoclonales Humanizados/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Anciano de 80 o más AñosRESUMEN
OBJECTIVE: Antenatal anaemia is associated with increased peripartum transfusion requirement in South Africa. We studied whether HIV was associated with the response to treatment of iron-deficiency anaemia. DESIGN: Prospective cohort study. SETTING: Hospital-based antenatal anaemia clinic in South Africa. SAMPLE: Equal-sized cohorts of pregnant women testing positive for HIV (HIV+) and testing negative for HIV (HIV-) with iron-deficiency anaemia. METHODS: Haemoglobin trajectories of women with confirmed iron-deficiency anaemia (ferritin < 50 ng/ml) were estimated from the initiation of iron supplementation using mixed-effects modelling, adjusted for baseline HIV status, ferritin level, maternal and gestational ages and time-varying iron supplementation. MAIN OUTCOME MEASURES: Haemoglobin trajectories. RESULTS: Of 469 women enrolled, 51% were HIV+, 90% of whom were on antiretroviral therapy (with a mean CD4+ lymphocyte count of 403 cells/mm3 ). Anaemia diagnoses did not differ by HIV status. A total of 400 women with iron-deficiency anaemia were followed during treatment with oral or intravenous (6%) iron therapy. In multivariable analysis, haemoglobin recovery was 0.10 g/dl per week slower on average in women who were HIV+ versus women who were HIV- (P = 0.001), 0.01 g/dl per week slower in women with higher baseline ferritin (P < 0.001) and 0.06 g/dl per week faster in women who were compliant with oral iron therapy (P = 0.002). CONCLUSIONS: Compared with women who were HIV-, women who were HIV+ with iron-deficiency anaemia had slower but successful haemoglobin recovery with iron therapy. Earlier effective management of iron deficiency could reduce the incidence of peripartum blood transfusion. TWEETABLE ABSTRACT: Among pregnant women with iron-deficiency anaemia in South Africa, HIV slows haemoglobin recovery in response to oral iron therapy.
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Anemia Ferropénica/tratamiento farmacológico , Infecciones por VIH , Hierro/administración & dosificación , Complicaciones Hematológicas del Embarazo/tratamiento farmacológico , Complicaciones Infecciosas del Embarazo , Atención Prenatal , Administración Intravenosa , Administración Oral , Adolescente , Adulto , Anemia Ferropénica/sangre , Estudios de Cohortes , Estudios Transversales , Femenino , Humanos , Hierro/sangre , Persona de Mediana Edad , Embarazo , Complicaciones Hematológicas del Embarazo/sangre , Estudios Prospectivos , Resultado del Tratamiento , Adulto JovenRESUMEN
BACKGROUND: The optimal duration of filgrastim as primary febrile neutropenia (FN) prophylaxis in early breast cancer patients is unknown, with 5, 7 or 10 days being commonly prescribed. This trial evaluates whether 5 days of filgrastim was non-inferior to 7/10 days. PATIENTS AND METHODS: In this randomised, open-label trial, early breast cancer patients who were to receive filgrastim as primary FN prophylaxis were randomly allocated to 5 versus 7 versus 10 days of filgrastim for all chemotherapy cycles. A protocol amendment in November 2017 allowed subsequent patients (N = 324) to be randomised to either 5 or 7/10 days. The primary outcome was a composite of either FN or treatment-related hospitalisations. Secondary outcomes included chemotherapy dose reductions, delays and discontinuations. Analyses were carried out by per protocol (primary) and intention-to-treat, and the non-inferiority margin was set at 3% for the risk of having FN and/or hospitalisation per cycle of chemotherapy. RESULTS: Patients (N = 466) were randomised to receive 5 (184, 39.5%), or 7/10 (282, 60.5%) days of filgrastim. In our primary analysis, the difference in risk of either FN or treatment-related hospitalisation per cycle was -1.52% [95% confidence interval (CI): -3.22% to 0.19%] suggesting non-inferiority of a 5-day filgrastim schedule compared with 7/10-days. The difference in events per cycle for FN was 0.11% (95% CI: -1.05 to 1.27) while for treatment-related hospitalisations it was -1.68% (95% CI: -2.73% to -0.63%). The overall proportions of patients having at least one occurrence of either FN or treatment-related hospitalisation were 11.8% and 14.96% for the 5- and 7/10-day groups, respectively (risk difference: -3.17%, 95% CI: -9.51% to 3.18%). CONCLUSION: Five days of filgrastim was non-inferior to 7/10 days. Given the cost and toxicity of this agent, 5 days should be considered standard of care. CLINICALTRIALS. GOV REGISTRATION: NCT02428114 and NCT02816164.
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Neoplasias de la Mama , Neutropenia Febril Inducida por Quimioterapia , Neutropenia Febril , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Neoplasias de la Mama/tratamiento farmacológico , Neutropenia Febril Inducida por Quimioterapia/epidemiología , Neutropenia Febril Inducida por Quimioterapia/etiología , Neutropenia Febril Inducida por Quimioterapia/prevención & control , Neutropenia Febril/inducido químicamente , Neutropenia Febril/epidemiología , Neutropenia Febril/prevención & control , Filgrastim/uso terapéutico , Factor Estimulante de Colonias de Granulocitos/uso terapéutico , Humanos , Polietilenglicoles/uso terapéutico , Proteínas Recombinantes/uso terapéuticoRESUMEN
Lifetimes of the first excited 2^{+} and 4^{+} states in the extremely neutron-deficient nuclide ^{172}Pt have been measured for the first time using the recoil-distance Doppler shift and recoil-decay tagging techniques. An unusually low value of the ratio B(E2:4_{1}^{+}â2_{1}^{+})/B(E2:2_{1}^{+}â0_{gs}^{+})=0.55(19) was found, similar to a handful of other such anomalous cases observed in the entire Segré chart. The observation adds to a cluster of a few extremely neutron-deficient nuclides of the heavy transition metals with neutron numbers N≈90-94 featuring the effect. No theoretical model calculations reported to date have been able to explain the anomalously low B(E2:4_{1}^{+}â2_{1}^{+})/B(E2:2_{1}^{+}â0_{gs}^{+}) ratios observed in these cases. Such low values cannot, e.g., be explained within the framework of the geometrical collective model or by algebraic approaches within the interacting boson model framework. It is proposed that the group of B(E2:4_{1}^{+}â2_{1}^{+})/B(E2:2_{1}^{+}â0_{gs}^{+}) ratios in the extremely neutron-deficient even-even W, Os, and Pt nuclei around neutron numbers N≈90-94 reveal a quantum phase transition from a seniority-conserving structure to a collective regime as a function of neutron number. Although a system governed by seniority symmetry is the only theoretical framework for which such an effect may naturally occur, the phenomenon is highly unexpected for these nuclei that are not situated near closed shells.
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The availability of purified antibodies is a prerequisite for many applications and the appropriate choice(s) for antibody-purification is crucial. Numerous methods have been developed for the purification of antibodies from different sources with affinity chromatography-based methods being the most extensively utilized. These methods are based on high specificity, easy reversibility and biological interactions between two molecules (e.g., between receptor and ligand or antibody and antigen). However, no simple techniques have yet been described to characterize and purify subclasses of immunoglobulins (Ig) from some animals of biotechnology importance such as equines, which are frequently used to produce biotherapeutic antibodies. The sera of these animals present a large number of Ig classes that have a greater complexity than other animals. The implementation of an effective protocol to purify the desired antibody class/subclasses requires meticulous planning to achieve yields at a high purity. The IgG3 subclass of equine-Ig has recently been used as antigen in a new diagnostic test for allergic responses to horse sera-based therapies. Here, we defined a simple method using Jacalin lectin immobilized on Sepharose beads to prepare highly pure equine IgG3 antibodies with a determination of the affinity constants for Jacalin lectin and horse IgG3.
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Inmunoglobulina G/química , Inmunoglobulina G/aislamiento & purificación , Lectinas/química , Temperatura , Animales , Cromatografía de Afinidad , Caballos , Inmunoglobulina G/inmunología , Lectinas/inmunología , Lectinas de Plantas/químicaRESUMEN
BACKGROUND: Taxane acute pain syndrome (TAPS) is characterized by myalgias and arthralgias starting 2-3 days after taxane-based chemotherapy and lasting up to 7 days. In the absence of validated tools, many studies use the presence of both the myalgia and arthralgia components of the Common Terminology Criteria for Adverse Events (CTCAE) to define TAPS. The present study prospectively evaluated the frequency, severity, and impact of TAPS in patients with breast or prostate cancer. PATIENTS AND METHODS: In this prospective, non-randomized study, patients with breast or prostate cancer commencing taxane-based chemotherapy completed the CTCAE (version 4.03), the Functional Assessment of Cancer Therapy-Taxane (FACT-T), and Brief Pain Inventory (BPI) questionnaires at baseline and once between days 5 and 7 of each chemotherapy cycle. RESULTS: From March 2015 to April 1, 2016, 75 patients (breast n = 66, prostate n = 9) were enrolled; 83% received docetaxel and 16% paclitaxel and 1% withdrew. After the first cycle of taxane, TAPS was reported by 25/69 (36.2%) patients; a further 8/69 (18.2%) reporting TAPS after a subsequent chemotherapy treatment. Overall incidence of TAPS was 33/75 (44%). While associated with detrimental scores on FACT-T and BPI as well as increased use of analgesics in 63% (21/33) of patients with TAPS, TAPS did not lead to alterations in chemotherapy dosing. CONCLUSIONS: TAPS is common after taxane-based chemotherapy, and its presence is associated with reduced quality of life and increased analgesic requirements. Prospective patient-reported outcome assessments are crucial to help individualize treatment strategies and improve management of TAPS.
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Dolor Agudo/tratamiento farmacológico , Artralgia/inducido químicamente , Neoplasias de la Mama/complicaciones , Hidrocarburos Aromáticos con Puentes/efectos adversos , Mialgia/inducido químicamente , Neoplasias de la Próstata/complicaciones , Taxoides/efectos adversos , Dolor Agudo/psicología , Neoplasias de la Mama/tratamiento farmacológico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Neoplasias de la Próstata/tratamiento farmacológico , Calidad de Vida , SíndromeRESUMEN
Discordance in estrogen (ER), progesterone (PR), and HER2/neu status between primary breast tumours and metastatic disease is well recognized. In this review, we highlight how receptor discordance between primary tumours and paired metastasis can help elucidate the mechanism of metastasis but can also effect patient management and the design of future trials. Discordance rates and ranges were available from 47 studies (3384 matched primary and metastatic pairs) reporting ER, PR, and HER2/neu expression for both primary and metastatic sites. Median discordance rates for ER, PR, and HER2/neu were 14 % (range 0-67 %, IQR 9-25 %), 21 % (range 0-62 %, IQR 15-41 %), and 10 % (range 0-44 %, IQR 4-17 %), respectively. Loss of receptor expression was more common (9.17 %) than gain (4.51 %). Discordance rates varied amongst site of metastasis with ER discordance being highest in bone metastases suggesting that discordance is a true biological phenomenon. Discordance rates vary for both the biomarker and the metastatic site. Loss of expression is more common than gain. This can affect patient management as it can lead to a reduction in both the efficacy and availability of potential therapeutic agents. Future studies are recommended to explore both the mechanisms of discordance as well as its impact on patient outcome and management.
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Biomarcadores de Tumor , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Receptor ErbB-2/metabolismo , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/metabolismo , Antineoplásicos Hormonales/farmacología , Antineoplásicos Hormonales/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/genética , Neoplasias de la Mama/terapia , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Terapia Molecular Dirigida , Metástasis de la Neoplasia , Estadificación de Neoplasias , Pronóstico , Receptor ErbB-2/genética , Receptores de Estrógenos/genética , Receptores de Progesterona/genética , Resultado del TratamientoRESUMEN
Many interesting but practically intractable problems can be reduced to that of finding the ground state of a system of interacting spins; however, finding such a ground state remains computationally difficult. It is believed that the ground state of some naturally occurring spin systems can be effectively attained through a process called quantum annealing. If it could be harnessed, quantum annealing might improve on known methods for solving certain types of problem. However, physical investigation of quantum annealing has been largely confined to microscopic spins in condensed-matter systems. Here we use quantum annealing to find the ground state of an artificial Ising spin system comprising an array of eight superconducting flux quantum bits with programmable spin-spin couplings. We observe a clear signature of quantum annealing, distinguishable from classical thermal annealing through the temperature dependence of the time at which the system dynamics freezes. Our implementation can be configured in situ to realize a wide variety of different spin networks, each of which can be monitored as it moves towards a low-energy configuration. This programmable artificial spin network bridges the gap between the theoretical study of ideal isolated spin networks and the experimental investigation of bulk magnetic samples. Moreover, with an increased number of spins, such a system may provide a practical physical means to implement a quantum algorithm, possibly allowing more-effective approaches to solving certain classes of hard combinatorial optimization problems.
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PURPOSE: To determine if asymmetry between hips in pain or radiographic osteoarthritis (RHOA) is associated with worse pain and joint space narrowing (JSN) at baseline and longitudinally in knees contralateral to more affected hips. METHODS: We studied 279 participants in the Osteoarthritis Initiative with baseline asymmetry between hips in pain and 483 with asymmetry in RHOA none of whom had a hip replacement for ≥4 years after baseline. RHOA assessed from pelvis radiographs was categorized as none, possible or definite and hip pain on most days of a month in the past year as present/absent. Knee pain (WOMAC scale) and JSN (fixed flexion radiographs) were categorized as none, mild and moderate-severe. We compared knees contralateral and ipsilateral to more affected hips on baseline knee pain and JSN using clustered multinomial regression and on change in knee pain and JSN over 4-5 years using generalized linear and logistic estimating equations. RESULTS: Knees contralateral to painful hips had less baseline pain ("moderate-severe" vs "none", relative risk ratio [RRR]: 0.39, 95% CI = 0.27-0.57), but greater baseline JSN ("moderate-severe" vs "none", RRR: 1.62, 95% CI = 1.09-2.38) and greater worsening of pain during follow-up (P = 0.001). Knees contralateral to hips with worse RHOA had nonsignificant trends for greater baseline JSN (P = 0.10) and JSN progression (P = 0.17). CONCLUSION: These findings provide limited support for the hypothesis that early asymmetry in hip pain and RHOA is associated with worse pain and structural outcomes in knees contralateral to the more affected hip.
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Osteoartritis de la Cadera/complicaciones , Osteoartritis de la Rodilla/etiología , Dolor/etiología , Anciano , Progresión de la Enfermedad , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Osteoartritis de la Cadera/diagnóstico por imagen , Osteoartritis de la Cadera/patología , Osteoartritis de la Rodilla/diagnóstico por imagen , Osteoartritis de la Rodilla/patología , Dolor/patología , Dimensión del Dolor/métodos , Radiografía/métodosRESUMEN
BACKGROUND: (131)I-metaiodobenzylguanidine (MIBG) is an active radiopharmaceutical in neuroblastoma. A previous study demonstrated that MIBG could be combined with vincristine and prolonged irinotecan, although 25% of first courses had grade 3 diarrhoea. The current phase I/II study evaluated MIBG with vincristine and 5 days of higher-dose irinotecan. METHODS: Patients 1-30 years old with advanced neuroblastoma were eligible. Patients received cefixime on days -1 to +6, irinotecan (50 mg m(-2) per dose IV) on days 0-4, vincristine (2 mg m(-2)) on day 0, MIBG (555 or 666 MBq kg(-1)) on day 1, and peripheral blood stem cells on day 13. UGT1A1 genotyping was performed in consenting patients. RESULTS: Thirty-two patients (12 phase I ; 20 phase II) received 42 courses. No dose-limiting toxicities were seen during dose escalation and the recommended administered activity was 666 MBq kg(-1). Myelosuppression and diarrhoea were the most common toxicities, with grade 3 diarrhoea in 6% of first courses. Patients homozygous for UGT1A1*28 had more grade 4 thrombocytopenia (80% vs 37%; P=0.14). Responses (five complete and four partial) occurred in 9 out of 32 (28%) patients. CONCLUSIONS: MIBG (666 MBq kg(-1)) with vincristine and this irinotecan schedule is tolerable and active, with less severe diarrhoea compared with a regimen using more protracted irinotecan.
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3-Yodobencilguanidina/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Camptotecina/análogos & derivados , Radioisótopos de Yodo/uso terapéutico , Neuroblastoma/terapia , Vincristina/administración & dosificación , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Camptotecina/administración & dosificación , Camptotecina/efectos adversos , Quimioradioterapia , Niño , Preescolar , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Femenino , Humanos , Irinotecán , Masculino , Dosis Máxima Tolerada , Neuroblastoma/genética , Dosificación Radioterapéutica , Vincristina/efectos adversos , Adulto JovenRESUMEN
BACKGROUND: De-escalation of bone-targeted agents, such as bisphosphonates and denosumab, from 4- to 12-weekly dosing is an increasingly used strategy in patients with bone metastases from breast cancer. It is unclear whether there is sufficient evidence to support de-escalation as a standard of care. METHODS: A systematic review of randomized trials comparing standard 4-weekly administration of bone-targeted agents with de-escalated (Q12-weekly) dosing in breast cancer patients was carried out. Medline, PubMed and the Cochrane Register of Controlled Trials were searched from inception until November 2014 for relevant studies. Outcomes of interest included skeletal-related event (SRE) rates, bone pain, adverse events (AEs) and bone turnover biomarkers. Random-effects meta-analyses were carried out. RESULTS: A total of nine citations representing seven unique studies were eligible. One study is ongoing with no reported data. Six studies reported data for at least one outcome of interest. Data were available comparing standard versus de-escalated therapy for pamidronate (1 study, 38 patients), zoledronate (3 studies, 1117 patients) and denosumab (2 studies, 284 patients). Meta-analysis of five trials reporting data for on-study SRE rates between standard (61/443 patients) and de-escalated (49/392 patients) arms produced a summary risk ratio of 0.90 (95% confidence interval 0.63-1.29). Meta-analyses of data for AEs and bone turnover biomarkers also showed no statistically significant differences between standard and de-escalated arms, though only limited numbers of patients and events were present for most analyses. CONCLUSION: In this systematic review of studies of bisphosphonates and denosumab, there appears to be no difference in SREs or pain with de-escalated therapy. While a large, hopefully definitive study is ongoing, the data presented so far are consistent with de-escalation of bone-targeting agents becoming a standard of care for patients with bone metastases from breast cancer.
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Conservadores de la Densidad Ósea/administración & dosificación , Neoplasias Óseas/diagnóstico , Neoplasias Óseas/secundario , Neoplasias de la Mama/diagnóstico , Nivel de Atención , Neoplasias Óseas/tratamiento farmacológico , Neoplasias de la Mama/tratamiento farmacológico , Ensayos Clínicos como Asunto/métodos , Esquema de Medicación , Femenino , Humanos , Nivel de Atención/normasRESUMEN
We report on the effects of six dyes used in the detection of DNA on the process of DNA extraction, amplification, and detection of STR loci. While dyes can be used to detect the presence of DNA, their use is restricted if they adversely affect subsequent DNA typing processes. Diamond™ Nucleic Acid Dye, GelGreen™, GelRed™, RedSafe™, SYBR(®) Green I, and EvaGreen™ were evaluated in this study. The percentage of dye removed during the extraction process was determined to be: 70.3% for SYBR(®) Green I; 99.6% for RedSafe™; 99.4% for EvaGreen™; 52.7% for Diamond™ Dye; 50.6% for GelRed™, and; could not be determined for GelGreen™. It was then assumed that the amount of dye in the fluorescent quantification assay had no effect on the DNA signal. The presence of all six dyes was then reviewed for their effect on DNA extraction. The t-test showed no significant difference between the dyes and the control. These extracts were then STR profiled and all dyes and control produced full DNA profiles. STR loci in the presence of GelGreen(TM) at 1X concentration showed increased amplification products in comparison to the control samples. Full STR profiles were detected in the presence of EvaGreen™ (1X), although with reduced amplification products. RedSafe™ (1X), Diamond™ Dye (1X), and SYBR(®) Green I (1X) all exhibited varying degrees of locus drop-out with GelRed™ generating no loci at all. We provide recommendations for the best dye to visualize the presence of DNA profile as a biological stain and its subsequent amplification and detection.
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Dermatoglifia del ADN/métodos , ADN/química , ADN/aislamiento & purificación , Colorantes Fluorescentes/química , Benzotiazoles , Diaminas , Técnicas de Amplificación de Ácido Nucleico , Compuestos Orgánicos/química , QuinolinasRESUMEN
Nucleic acid staining dyes are used for detecting nucleic acids in electrophoresis gels. Historically, the most common dye used for gel staining is ethidium bromide, however due to its toxicity and mutagenicity other dyes that are safer to the user and the environment are preferred. This Short Communication details the properties of dyes now available and their sensitivity for detection of DNA and their ability to permeate the cell membrane. It was found that GelRed™ was the most sensitive and safest dye to use with UV light excitation, and both GelGreen™ and Diamond™ Nucleic Acid Dye were sensitive and the safer dyes using blue light excitation.
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Electroforesis en Gel de Agar/métodos , Etidio/química , Colorantes Fluorescentes/química , Ácidos Nucleicos/análisis , Permeabilidad de la Membrana Celular , Límite de Detección , Ácidos Nucleicos/químicaRESUMEN
Until recently, the use of neoadjuvant endocrine therapy was mainly restricted to those patients whose general frailty or comorbidities were contraindications to surgery. There is now increased evidence that certain patient populations (i.e. older patients with hormone-receptor positive disease) can gain as good a pathologic response, with considerably less toxicity, from neoadjuvant endocrine therapy than from neoadjuvant chemotherapy. Optimization of neoadjuvant endocrine therapy is therefore an important therapeutic goal. However, possibly of greater importance in the overall management of breast cancer, is the increased interest in exploring the effects of brief periods of endocrine therapy on in vivo biomarkers, in so called window of opportunity trials. These trials can not only be used to identify the mechanisms of action of novel agents but also to predict optimal subsequent adjuvant therapy for individual patients. While this paper will briefly review the history of neoadjuvant endocrine therapy, more emphasis will be on the evaluation of pivotal window of opportunity trials that will likely lead to a long awaited paradigm shift in the management of breast cancer.
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Antineoplásicos Hormonales/uso terapéutico , Inhibidores de la Aromatasa/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Moduladores de los Receptores de Estrógeno/uso terapéutico , Terapia Neoadyuvante , Biomarcadores de Tumor/sangre , Neoplasias de la Mama/sangre , Neoplasias de la Mama/diagnóstico , Ensayos Clínicos como Asunto , Detección Precoz del Cáncer , Medicina Basada en la Evidencia , Femenino , Humanos , Terapia Neoadyuvante/métodos , Pronóstico , Resultado del TratamientoRESUMEN
In recent years, considerable attention has been paid to the role of neoadjuvant chemotherapy as a pluripotential test bed for the treatment of breast cancer. Although traditionally reserved to render inoperable disease operable, neoadjuvant chemotherapy is increasingly being used to improve the chance for breast-conserving surgery, to gain information on pathologic response rates for a more rapid assessment of new chemotherapy-biologic regimens, and also to study in vivo tumour sensitivity or resistance to the agent being used. Similarly, use of neoadjuvant endocrine treatment was also traditionally restricted to elderly or frail patients who were felt to be unsuitable for chemotherapy. It is therefore not surprising that, given the increasing realization of the pivotal role of endocrine therapy in patient care, there is enhanced interest in neoadjuvant endocrine therapy not only as a less-toxic alternative to chemotherapy, but also to assess tumour sensitivity or resistance to endocrine agents. The availability of newer endocrine manipulations and increasing evidence that the benefits of chemotherapy are frequently marginal in many hormone-positive patients is making endocrine therapy increasingly important in the clinical setting. The hope is that, one day, instead of preoperative endocrine therapy being restricted to the infirm and the elderly, it will be used in the time between biopsy diagnosis and surgery to predict which patients will or will not benefit from chemotherapy in the adjuvant setting.
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The AJCC staging criteria consider tumor size to be the largest dimension of largest tumor. Some case series suggest using summation of all tumor dimensions in patients with multicentric/multifocal (MC/MF) disease. We used data from NCIC CTG MA.5 and MA.12 clinical trials to examine alternative methods of assessing tumor size on breast-cancer-free-interval (BCFI). The 710 MA.5 pre-/peri-menopausal node positive and 672 MA.12 pre-menopausal node-negative/-positive patients have 10-year median follow-up. All patients received adjuvant chemotherapy. Tumors were centrally reviewed for grade, hormone receptor, and HER2 status. Continuous pathologic tumor size was: (1) largest dimension of largest tumor (cm); (2) tumor area (cm(2)); (3) volume of tumor (cm(3)); (4) with MC/MF disease, summation of (1)-(3) for up to 3 foci. We examined univariate and multivariate effects of tumor size on BCFI utilizing (un)stratified Cox regression and the Wald test statistic. In univariate analysis, larger tumor dimension was significantly associated with worse BFCI in node positive patients: p < 0.0001 for MA.5; p = 0.01 for MA.12. In MA.5 multivariate analysis, larger summation of largest tumor dimensions was associated with worse BCFI (p = 0.0003), while larger single dimension was associated with worse BCFI (p = 0.02) for MA.12. Presence of MC/MF and other tumor size measurements were not associated (p > 0.05) with BFCI. While physicians could consider the largest diameter of the largest focus of disease or the sum of the largest diameters of all foci in their T-stage determination, it appears that the current method of T-staging offers equivalent determinations of prognosis.
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Neoplasias de la Mama/patología , Adulto , Anciano , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/mortalidad , Ensayos Clínicos Fase III como Asunto , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Clasificación del Tumor , Estadificación de Neoplasias , Pronóstico , Factores de Riesgo , Carga TumoralRESUMEN
BACKGROUND: Obesity is highly prevalent in asthmatic children and associated with worse clinical outcomes. Energy restriction to induce weight loss in asthmatic children has not been investigated in a randomized controlled trial (RCT). OBJECTIVE: To assess if (1) weight loss can be achieved in obese asthmatic children using a dietary intervention; and (2) changes in asthma outcomes occur following diet-induced weight loss. METHODS: In a 10-week pilot RCT, obese asthmatic children, aged 8-17 years, were randomized to a wait-list control (WLC) (n = 15) or dietary-intervention group (DIG) (n = 13). Lung function, Asthma Control Questionnaire (ACQ) score, and sputum and systemic inflammation were assessed at baseline and post-intervention. (Australian New Zealand Clinical Trials Registry: ACTRN12610000955011). RESULTS: Body mass index (BMI) z-score reduced significantly in the DIG vs. the WLC (-0.2 [-0.4, -0.1] vs. 0.0 [-0.1, 0.0], P = 0.014). Expiratory reserve volume (ERV) increased significantly within the DIG, but not compared to the WLC (0.7 [0.0, 1.0] L vs. 0.3 [0.0, 0.8] L, P = 0.355). ACQ improved significantly in the DIG, compared to the WLC (-0.4 [-0.7, 0.0] vs. 0.1 [0.0, 0.6], P = 0.004). Airway and systemic inflammation did not change within the DIG. In comparison, C-Reactive Protein (CRP) increased significantly in the WLC (-0.4 [-0.5, 0.4] vs. 0.7 [-0.1, 1.9], P = 0.037). Change (∆) in BMI z-score correlated with ∆CRP (r = 0.47, P = 0.012) and ∆exhaled nitric oxide (eNO) (r = 0.46, P = 0.034), and ∆ACQ was associated with ∆CRP (r = 0.43, P = 0.029). CONCLUSION AND CLINICAL RELEVANCE: Dietary intervention can induce acute weight loss in obese asthmatic children with subsequent improvements in static lung function and asthma control. Systemic and airway inflammation did not change following weight loss. However, changes in BMI z-score were associated with changes in airway and systemic inflammation and this requires further investigation in a larger RCT. This is the first weight loss RCT conducted in obese asthmatic children. Diet-induced weight loss can achieve significant improvements in clinical outcomes for obese children with asthma.
Asunto(s)
Asma , Índice de Masa Corporal , Restricción Calórica/métodos , Pulmón , Encuestas y Cuestionarios , Pérdida de Peso , Adolescente , Asma/dietoterapia , Asma/patología , Asma/fisiopatología , Niño , Femenino , Humanos , Pulmón/patología , Pulmón/fisiopatología , Masculino , Obesidad , Pruebas de Función Respiratoria/métodosRESUMEN
OBJECTIVE: To describe cartilage matrix and morphology changes, assessed using quantitative magnetic resonance imaging (MRI), after acute anterior cruciate ligament (ACL) injury relative to controls and longitudinally during 2 years following reconstruction. METHOD: Fifteen patients with acute ACL injuries and 16 healthy volunteers with a similar demographic profile but no history of osteoarthritis or knee injury were studied. The injured knee of each participant was imaged with a 3.0 T MR scanner at baseline (prior to ACL reconstruction); patients' knees were re-imaged 1 and 2 years after ACL reconstruction. Cartilage T1ρ and T2 values in full thickness, superficial layers, and deep layers, and cartilage thickness of the full layer were quantified within subcompartments of the knee joint. RESULTS: In the posterolateral tibial cartilage, T1ρ values were significantly higher in ACL-injured knees than control knees at baseline and were not fully recovered 2 after ACL reconstruction. T1ρ values of medial tibiofemoral cartilage in ACL-injured knees increased over the 2-year study and were significantly elevated compared to that of the control knees. T2 values in cartilage of the central aspect of the medial femoral condyle at the 2-year follow-up were significantly elevated compared with control knees. Cartilage in the posterior regions of the lateral tibia was significantly thinner, while cartilage in the central aspect of the medial femur was significantly thicker than that of controls. Patients with lesions in the posterior horn of the medial meniscus exhibited significantly higher T1ρ values in weight-bearing regions of the tibiofemoral cartilage than that of control subjects over the 2-year period, whereas patients without medial meniscal tears did not. CONCLUSION: Quantitative MRI provides powerful in vivo tools to quantitatively evaluate early changes of cartilage matrix and morphology after acute ACL injury and reconstruction, which may possibly relate to the development of post-traumatic osteoarthritis in such joints.
Asunto(s)
Lesiones del Ligamento Cruzado Anterior , Reconstrucción del Ligamento Cruzado Anterior/efectos adversos , Cartílago Articular/patología , Traumatismos de la Rodilla/cirugía , Adulto , Ligamento Cruzado Anterior/patología , Ligamento Cruzado Anterior/cirugía , Reconstrucción del Ligamento Cruzado Anterior/métodos , Índice de Masa Corporal , Estudios de Casos y Controles , Progresión de la Enfermedad , Femenino , Fémur/patología , Estudios de Seguimiento , Humanos , Traumatismos de la Rodilla/patología , Imagen por Resonancia Magnética/métodos , Masculino , Meniscos Tibiales/patología , Persona de Mediana Edad , Osteoartritis de la Rodilla/etiología , Rótula/patología , Tibia/patología , Adulto JovenRESUMEN
Here we describe a capillary electrophoretic method for the separation of double-stranded oligonucleotides (ds-ODNs) ranging from 16-20 bp with 2 bp resolution using a low concentration of poly(ethylpyrrolidine methacrylate-co-methyl methacrylate) (PEPyM-co-PMMA) copolymer physically adsorbed to a capillary surface. Contrary to traditional DNA separations, we show that the ds-ODN with the highest molecular size eluted first and propose that this phenomena is due to a screening effect by the PEPyM-co-PMMA coating on the smaller ds-ODNs negative charge during elution. Key to the performance of this separation was a sample preparation time of less than 1 h and analysis time of 40 min. Repeatability of intraday migration time for the mixtures was typically < 1% relative standard deviation (n = 3). In addition, we demonstrate that the coating has an acceptable capillary lifetime of over 70 injections.