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1.
J Am Chem Soc ; 145(34): 19129-19139, 2023 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-37556835

RESUMO

Discovering new bioactive molecules is crucial for drug development. Finding a hit compound for a new drug target usually requires screening of millions of molecules. Affinity selection based technologies have revolutionized early hit discovery by enabling the rapid screening of libraries with millions or billions of compounds in short timeframes. In this Perspective, we describe recent technology breakthroughs that enable the screening of ultralarge synthetic peptidomimetic libraries with a barcode-free tandem mass spectrometry decoding strategy. A combination of combinatorial synthesis, affinity selection, automated de novo peptide sequencing algorithms, and advances in mass spectrometry instrumentation now enables hit discovery from synthetic libraries with over 100 million members. We provide a perspective on this powerful technology and showcase success stories featuring the discovery of high affinity binders for a number of drug targets including proteins, nucleic acids, and specific cell types. Further, we show the usage of the technology to discover synthetic peptidomimetics with specific functions and reactivity. We predict that affinity selection coupled with tandem mass spectrometry and automated de novo decoding will rapidly evolve further and become a broadly used drug discovery technology.


Assuntos
Bibliotecas de Moléculas Pequenas , Espectrometria de Massas em Tandem , Espectrometria de Massas em Tandem/métodos , Bibliotecas de Moléculas Pequenas/química , Descoberta de Drogas , Sequência de Aminoácidos
2.
Reprod Fertil Dev ; 30(11): 1541-1552, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29778102

RESUMO

The aim of the present study was to investigate the effects of a strategy for extending pro-oestrus (the interval between luteolysis and ovulation) in an oestrus synchronisation protocol (named J-Synch) in beef heifers on follicular growth, sexual steroid concentrations, the oestrogen receptor ERα and progesterone receptors (PR) in the uterus, insulin-like growth factor (IGF) 1 and pregnancy rates. In Experiment 1, heifers treated with the new J-Synch protocol had a longer pro-oestrus period than those treated with the conventional protocol (mean (±s.e.m.) 93.7±12.9 vs 65.0±13.7h respectively; P<0.05). The rate of dominant follicle growth from the time of progesterone device removal to ovulation was greater in heifers in the J-Synch than conventional group (P<0.05). Luteal area and serum progesterone concentrations were greater in the J-Synch Group (P<0.05) for the 12 days after ovulation. Progesterone receptor (PGR) staining on Day 6 after ovulation in the uterine stroma was lower in the J-Synch than conventional group (P<0.05), and the expression of PR gene (PGR) and IGF1 gene tended to be lower in J-Synch-treated heifers (P<0.1). In Experiment 2 (n=2349), the pregnancy rate 30-35 days after fixed-time AI (FTAI) was greater for heifers in the J-Synch than conventional group (56.1% vs 50.7% respectively). In conclusion, our strategy for extending pro-oestrus (i.e. the J-Synch protocol) significantly improves pregnancy establishment in beef heifers. This improvement was related to an increased rate of growth of the dominant ovulatory follicle, greater progesterone concentrations during the ensuing luteal phase and different uterine patterns of PGR and IGF1, which may have favoured embryo development and pregnancy establishment.


Assuntos
Estradiol/análogos & derivados , Sincronização do Estro/fisiologia , Ovário/fisiologia , Proestro/fisiologia , Progesterona/administração & dosagem , Útero/fisiologia , Animais , Bovinos , Estradiol/administração & dosagem , Estradiol/sangue , Sincronização do Estro/efeitos dos fármacos , Feminino , Folículo Ovariano/diagnóstico por imagem , Folículo Ovariano/efeitos dos fármacos , Ovário/diagnóstico por imagem , Ovário/efeitos dos fármacos , Gravidez , Proestro/efeitos dos fármacos , Progesterona/sangue , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Útero/diagnóstico por imagem , Útero/efeitos dos fármacos
3.
Acta Anaesthesiol Scand ; 62(5): 620-627, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29377065

RESUMO

BACKGROUND: Pre-operative complex carbohydrate (CHO) drinks are recommended to attenuate post-operative insulin resistance. However, many institutions use simple CHO drinks, which while convenient, may have less metabolic effects. Whey protein may enhance insulin release when added to complex CHO. The aim of this study was to compare the insulin response to simple CHO vs. simple CHO supplemented with whey protein. METHODS: Twelve healthy volunteers participated in this double-blinded, within subject, cross-over design study investigating insulin response to simple CHO drink vs. simple CHO + whey (CHO + W) drink. The primary outcome was the accumulated insulin response during 180 min after ingestion of the drinks (Area under the curve, AUC). Secondary outcomes included plasma glucose and ghrelin levels, and gastric emptying rate estimated by acetaminophen absorption technique. Data presented as mean (SD). RESULTS: There was no differences in accumulated insulin response after the CHO or CHO + W drinks [AUC: 15 (8) vs. 20 (14) nmol/l, P = 0.27]. Insulin and glucose levels peaked between 30 and 60 min and reached 215 (95) pmol/l and 7 (1) mmol/l after the CHO drink and to 264 (232) pmol/l and 6.5 (1) mmol/l after the CHO + W drink. There were no differences in glucose or ghrelin levels or gastric emptying with the addition of whey. CONCLUSION: The addition of whey protein to a simple CHO drink did not change the insulin response in healthy individuals. The peak insulin responses to simple CHO with or without whey protein were lower than that previously reported with complex CHO drinks. The impact of simple carbohydrate drinks with lower insulin response on peri-operative insulin sensitivity requires further study.


Assuntos
Glicemia/análise , Carboidratos da Dieta/administração & dosagem , Insulina/sangue , Proteínas do Soro do Leite/administração & dosagem , Adulto , Idoso , Estudos Cross-Over , Método Duplo-Cego , Esvaziamento Gástrico , Grelina/sangue , Humanos , Pessoa de Meia-Idade
4.
Int J Sports Med ; 37(13): 1019-1024, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27676149

RESUMO

This study compared the acute cytokine response, and kinetic and kinematic profile following back squat exercise in resistance-trained men. In a randomized, cross-over design, 10 resistance-trained men (27±4 y, 1.80±0.07 m, 82.8±6.7 kg, 16.3±3.5% fat) performed the back squat exercise using traditional and cluster set configurations. Kinetic and kinematic data were sampled throughout each condition. Venous blood was sampled prior, immediately post, 30 min, 60 min, 24 h, and 48 h post-exercise for plasma interleukin-6 (IL-6) and interleukin-15 (IL-15). Cluster sets allowed for greater mean power (mean difference, 110 W; 90% confidence interval, ±63 W; benefit odds, 41 447:1), driven by higher overall mean velocities (0.053 m∙s-1; 0.039 m∙s-1; 3 105:1) as evidenced by the lack of clear contrasts for mean force. IL-15 increased post-exercise in both conditions, but increased at 24 h (0.13 pg·mL-1; ±0.11 pg·mL-1; 486:1) and 48 h (0.12 pg·mL-1; ±0.10 pg·mL-1; 667:1) in traditional sets only. IL-6 increased similarly in both conditions, post-exercise through 60 min post. Cluster set configurations allow for greater mean power, attributed to higher velocities. Despite a similar response of IL-6, traditional set configuration may provide a greater stimulus for hypertrophy as evidenced by a secondary increase in IL-15.


Assuntos
Interleucina-15/sangue , Interleucina-6/sangue , Músculo Esquelético/fisiologia , Treinamento Resistido/métodos , Adulto , Fenômenos Biomecânicos , Estudos Cross-Over , Humanos , Hipertrofia , Masculino , Adulto Jovem
5.
Radiologia ; 57(4): 303-13, 2015.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-25747807

RESUMO

Hyperpolarized (HP) gases are a new class of contrast agents that permit to obtain high temporal and spatial resolution magnetic resonance images (MRI) of the lung airspaces. HP gas MRI has become important research tool not only for morphological and functional evaluation of normal pulmonary physiology but also for regional quantification of pathologic changes occurring in several lung diseases. The purpose of this work is to provide an introduction to MRI using HP noble gases, describing both the basic principles of the technique and the new information about lung disease provided by clinical studies with this method. The applications of the technique in normal subjects, smoking related lung disease, asthma, and cystic fibrosis are reviewed.


Assuntos
Meios de Contraste , Hélio , Pneumopatias/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Xenônio , Humanos
7.
BMJ Mil Health ; 2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37220991

RESUMO

INTRODUCTION: Little is known of the epidemiology of musculoskeletal injuries (MSKIs) in US Air Force Special Warfare (AFSPECWAR) Tactical Air Control Party trainees. The purpose of this longitudinal retrospective cohort study was to (1) report the incidence and type of MSKI sustained by AFSPECWAR trainees during and up to 1 year following training, (2) identify factors associated with MSKI, and (3) develop and present the MSKI classification matrix used to identify and categorise injuries in this study. METHODS: Trainees in the Tactical Air Control Party Apprentice Course between fiscal years 2010-2020 were included. Diagnosis codes were classified as MSKI or non-MSKI using a classification matrix. Incidence rates and incidence proportion for injury types and regions were calculated. Measures were compared for differences between those who did and did not sustain an MSKI during training. A Cox proportional hazards model was used to identify factors associated with MSKI. RESULTS: Of the 3242 trainees, 1588 (49%) sustained an MSKI during training and the cohort sustained MSKIs at a rate of 16 MSKI per 100 person-months. Overuse/non-specific lower extremity injuries predominated. Differences were seen in some baseline measures between those who did and did not sustain an MSKI. Factors retained in the final Cox regression model were age, 1.5-mile run times and prior MSKI. CONCLUSION: Slower run times and higher age were associated with an increased likelihood of MSKI. Prior MSKI was the strongest predictor of MSKI during training. Trainees sustained MSKIs at a higher rate than graduates in their first year in the career field. The MSKI matrix was effective in identifying and categorising MSKI over a prolonged (12-year) surveillance period and could be useful for future injury surveillance efforts in the military or civilian settings. Findings from this study could inform future injury mitigation efforts in military training environments.

8.
Med Intensiva ; 36(1): 32-6, 2012.
Artigo em Espanhol | MEDLINE | ID: mdl-22177845

RESUMO

Life-sustaining treatment limitation (LSTL) is an increasingly common practice. However, its application is sometimes not clearly reflected in the clinical record-this giving rise to the adoption of measures that could have been avoided, including admission to the intensive care unit (ICU), with the suffering and economical costs this implies. One way to trace patients subjected to LSTL is through an electronic registry allowing identification at all times of these individuals, and of the therapies that have been restricted in each case. The Ethics Committee of our center has developed a tool allowing the identification of patients subjected to LSTL and of the level of intervention required, and offering the association of a patient comfort management protocol.


Assuntos
Cuidados Críticos/ética , Registros Eletrônicos de Saúde , Registros Hospitalares , Cuidados para Prolongar a Vida , Futilidade Médica , Recusa em Tratar , Assistência Terminal , Cuidados Críticos/organização & administração , Humanos , Hipnóticos e Sedativos/uso terapêutico , Consentimento Livre e Esclarecido , Unidades de Terapia Intensiva/organização & administração , Cuidados para Prolongar a Vida/ética , Competência Mental , Entorpecentes/uso terapêutico , Cuidados Paliativos , Seleção de Pacientes , Recusa em Tratar/ética , Ordens quanto à Conduta (Ética Médica) , Espanha , Assistência Terminal/ética , Assistência Terminal/organização & administração , Recusa do Paciente ao Tratamento , Procedimentos Desnecessários
9.
Artigo em Alemão | MEDLINE | ID: mdl-21547645

RESUMO

The proportion of overweight and obese children and adolescents in Germany and Europe has increased dramatically since the 1990s. About a third of obese preschool children and half of obese school children will become obese adults; the economic, medical, and psychosocial consequences are substantial. This article presents an overview of psychological risk factors and causes of obesity in children and adolescents, including comorbidity with psychological disorders, stigmatization, and relationships with peers, family, and other environment factors, as well as interactions between genes and behavior. Understanding risk factors and causes for obesity is the basis for adequate psychological interventions. We provide an overview of psychological aspects of obesity, such as motivation and impulsivity, and present components of cognitive behavioral therapy and modalities of intervention. A better understanding of psychological factors is necessary to achieve more effective interventions and long-term success of behavior change. This also holds true for changes in the social, media, and physical environment structures with the goal of promoting healthy eating and physical activity.


Assuntos
Terapia Cognitivo-Comportamental/estatística & dados numéricos , Terapia Cognitivo-Comportamental/tendências , Obesidade/psicologia , Obesidade/terapia , Adolescente , Causalidade , Criança , Alemanha/epidemiologia , Humanos , Obesidade/epidemiologia , Prevalência , Medição de Risco , Fatores de Risco
10.
Clin Transl Oncol ; 23(8): 1511-1519, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33583005

RESUMO

Discovery and clinical development of monoclonal antibodies with the ability to interfere in the regulation of the immune response have significantly changed the landscape of oncology in recent years. Among the active agents licensed by the regulatory agencies, nivolumab and pembrolizumab are paradigmatic as the most relevant ones according to the magnitude of available data derived from the extensive preclinical and clinical experience. Although in both cases the respective data sheets indicate well-defined dosage regimens, a review of the literature permits to verify the existence of many issues still unresolved about dosing the two agents, so it must be considered an open question of potentially important consequences, in which to work to improve the effectiveness and efficiency of use.


Assuntos
Anticorpos Monoclonais Humanizados/administração & dosagem , Antineoplásicos Imunológicos/administração & dosagem , Inibidores de Checkpoint Imunológico/administração & dosagem , Neoplasias/tratamento farmacológico , Nivolumabe/administração & dosagem , Anticorpos Monoclonais Humanizados/farmacocinética , Anticorpos Monoclonais Humanizados/uso terapêutico , Antineoplásicos Imunológicos/farmacocinética , Antineoplásicos Imunológicos/uso terapêutico , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Imunoterapia Adotiva/métodos , Nivolumabe/farmacocinética , Nivolumabe/uso terapêutico , Receptor de Morte Celular Programada 1/antagonistas & inibidores
11.
Antibiotics (Basel) ; 10(2)2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-33573154

RESUMO

Nine new complexes with camphor imine or camphor sulfonimine ligands were synthesized and analytically and spectroscopically characterized, aiming to identify the key parameters that drive the antibacterial activity of the complexes with metal cores and imine substituents with distinct electronic and steric characteristics. The antimicrobial activity of all complexes was evaluated by determining their minimum inhibitory concentrations (MIC) against the Gram-negative Escherichia coli ATCC25922, Pseudomonas aeruginosa 477, and Burkholderia contaminans IST408, and the Gram-positive Staphylococcus aureus Newman. Camphor imine complexes based on the hydroxyl silver center ({Ag(OH)}) typically perform better than those based on the nitrate silver center ({Ag(NO3)}), while ligands prone to establish hydrogen bonding facilitate interactions with the bacterial cell surface structures. A different trend is observed for the silver camphor sulfonimine complexes that are almost non-sensitive to the nature of the metal cores {Ag(OH)} or {Ag(NO3)} and display low sensitivity to the Y substituent. The antibacterial activities of the Ag(I) camphor sulfonimine complexes are higher than those of the camphor imine analogues. All the complexes display higher activity towards Gram-negative strains than towards the Gram-positive strain.

12.
Int J Pharm ; 593: 120110, 2021 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-33246052

RESUMO

Wound care remains a challenge in healthcare. This work aimed to develop a new polyvinyl alcohol (PVA)/chitosan (Ch) based wound dressing able to ensure protection, hydration and a controlled release of antiseptics, as alternative to actual treatments. Two distinct formulations (1:1 and 3:1, w/w) were prepared, sterilized by autoclaving and characterized concerning surface morphology, degradation over the time, mechanical properties and hydrophilicity. Both dressings revealed adequate properties for the intended purpose. The dressings were loaded with chlorhexidine (CHX) and polyhexanide (PHMB) and the drug release profiles were determined using Franz diffusion cells. The release of PHMB was more sustained than CHX, lasting for 2 days. As the amounts of drugs released by PVA/Ch 1:1 were greater, the biological tests were done only with this formulation. The drug loaded dressings revealed antibacterial activity against S. aureus and S. epidermidis, but only the ones loaded with PHMB showed adequate properties in terms of cytotoxicity and irritability. The application of this elastic dressing in the treatment of wounds in a dog led to faster recovery than conventional treatment, suggesting that the material can be a promising alternative in wound care.


Assuntos
Anti-Infecciosos Locais , Quitosana , Animais , Antibacterianos/farmacologia , Bandagens , Cães , Álcool de Polivinil , Staphylococcus aureus , Cicatrização
13.
Clin Transl Oncol ; 23(10): 2099-2108, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33864619

RESUMO

PURPOSE: We aimed to evaluate the current situation of electronic health records (EHRs) and patient registries in the oncology departments of hospitals in Spain. METHODS: This was a cross-sectional study conducted from December 2018 to September 2019. The survey was designed ad hoc by the Outcomes Evaluation and Clinical Practice Section of the Spanish Society of Medical Oncology (SEOM) and was distributed to all head of medical oncology department members of SEOM. RESULTS: We invited 148 heads of oncology departments, and 81 (54.7%) questionnaires were completed, with representation from all 17 Spanish autonomous communities. Seventy-seven (95%) of the respondents had EHRs implemented at their hospitals; of them, over 80% considered EHRs to have a positive impact on work organization and clinical practice, and 73% considered that EHRs improve the quality of patient care. In contrast, 27 (35.1%) of these respondents felt that EHRs worsened the physician-patient relationship and conveyed an additional workload (n = 29; 37.6%). Several drawbacks in the implementation of EHRs were identified, including the limited inclusion of information on both outpatients and inpatients, information recorded in free text data fields, and the availability of specific informed consent. Forty-six (56.7%) respondents had patient registries where they recorded information from all patients seen in the department. CONCLUSION: Our study indicates that EHRs are almost universally implemented in the hospitals surveyed and are considered to have a positive impact on work organization and clinical practice. However, EHRs currently have several drawbacks that limit their use for investigational purposes. CLINICAL TRIAL REGISTRATION: Not applicable.


Assuntos
Registros Eletrônicos de Saúde/estatística & dados numéricos , Oncologia/estatística & dados numéricos , Serviço Hospitalar de Oncologia/estatística & dados numéricos , Sistema de Registros/estatística & dados numéricos , Atitude do Pessoal de Saúde , Estudos Transversais , Prescrição Eletrônica/estatística & dados numéricos , Humanos , Relações Médico-Paciente , Qualidade da Assistência à Saúde , Espanha , Inquéritos e Questionários/estatística & dados numéricos , Carga de Trabalho
14.
BJS Open ; 4(5): 830-839, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32762036

RESUMO

BACKGROUND: Laparoscopic subtotal gastrectomy (LSG) for cancer is associated with good perioperative outcomes and superior quality of life compared with the open approach, albeit at higher cost. An economic evaluation was conducted to compare the two approaches. METHODS: A cost-effectiveness analysis between LSG and open subtotal gastrectomy (OSG) for gastric cancer was performed using a decision-tree cohort model with a healthcare system perspective and a 12-month time horizon. Model inputs were informed by a meta-analysis of relevant literature, with costs represented in 2016 Canadian dollars (CAD) and outcomes measured in quality-adjusted life-years (QALYs). A secondary analysis was conducted using inputs extracted solely from European and North American studies. Deterministic (DSA) and probabilistic (PSA) sensitivity analyses were performed. RESULTS: In the base-case model, costs of LSG were $935 (€565) greater than those of OSG, with an incremental gain of 0·050 QALYs, resulting in an incremental cost-effectiveness ratio of $18 846 (€11 398) per additional QALY gained from LSG. In the DSA, results were most sensitive to changes in postoperative utility, operating theatre and equipment costs, as well as duration of surgery and hospital stay. PSA showed that the likelihood of LSG being cost-effective at willingness-to-pay thresholds of $50 000 (€30 240) per QALY and $100 000 (€60 480) per QALY was 64 and 68 per cent respectively. Secondary analysis using European and North American clinical inputs resulted in LSG being dominant (cheaper and more effective) over OSG, largely due to reduced length of stay after LSG. CONCLUSION: In this decision analysis model, LSG was cost-effective compared with OSG for gastric cancer.


ANTECEDENTES: Pese a su mayor coste, la gastrectomía subtotal laparoscópica se asocia con buenos resultados perioperatorios y una mejor calidad de vida en comparación con la cirugía abierta en el tratamiento del cáncer. Se realizó una evaluación económica comparando los dos abordajes. MÉTODOS: Se efectuó un análisis de coste-efectividad de la gastrectomía subtotal laparoscópica (laparoscopic subtotal gastrectomy, LSG) o de la gastrectomía subtotal abierta (open subtotal gastrectomy, OSG) en el cáncer gástrico utilizando un modelo de cohortes con árbol de decisión desde la perspectiva del sistema de salud y con un horizonte temporal de 12 meses. Los gastos del modelo fueron evaluados tras un metaanálisis de literatura relevante y expresados en dólares canadienses (Canadian dollars, CAD) del 2016. Los resultados se midieron en años de vida ajustados por su calidad (quality-adjusted life years, QALYs). Se realizó un análisis secundario utilizando los datos extraídos únicamente de estudios europeos y norteamericanos. Además, se realizaron análisis de sensibilidad determinístico y probabilístico (deterministic and probabilistic sensitivity analyses, DSA y PSA). RESULTADOS: En el modelo del caso base, los costes de la LSG fueron de 934,78$ (565€) más que en la OSG, con una ganancia incremental de 0,050 QALYs, que supuso una relación coste-efectividad incremental (incremental cost-effectiveness ratio, ICER) de 18.846,12$ (11.398€) por QALY adicional en la LSG. En el DSA, los resultados fueron más sensibles a cambios en el postoperatorio, quirófano y coste de los equipos, así como en la duración de la intervención y la hospitalización. El PSA demostró que la probabilidad de que la LSG fuera rentable en términos de disposición de pago (willingness-to-pay, WTP) para dos umbrales, de 50.000$ (30.240€) y 100.000$ (60.480€) por QALY fue del 64% y del 68%, respectivamente. En el análisis secundario utilizando los datos europeos y norteamericanos se demostró que la LSG era claramente dominante (más barata y más efectiva) que la OSG, en gran parte debido a la reducción de la estancia hospitalaria de la LSG. CONCLUSIÓN: En este modelo de análisis de decisión, la LSG fue coste-efectiva en comparación con la OSG para el cáncer gástrico.


Assuntos
Adenocarcinoma/cirurgia , Análise Custo-Benefício , Gastrectomia/métodos , Laparoscopia/métodos , Neoplasias Gástricas/cirurgia , Adenocarcinoma/economia , Gastrectomia/economia , Humanos , Laparoscopia/economia , Anos de Vida Ajustados por Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Neoplasias Gástricas/economia
15.
Theriogenology ; 151: 16-27, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32251936

RESUMO

The objective of the present study was to evaluate the effect of equine chorionic gonadotropin (eCG) administration associated to different proestrus lengths for Fixed-time AI (FTAI) in beef heifers. In Experiment 1, pre-pubertal heifers (n = 46) received a 6-day estradiol/progesterone-based treatment (J-Synch protocol), and were then allocated into four experimental groups in a 2 × 2 factorial design, to receive or not receive eCG (300 IU) at the time of intravaginal progesterone device removal, and to receive GnRH at 48 h or 72 h after device removal (to induce shortened and prolonged proestrus length, respectively). Endometrial samples were obtained 6 d after ovulation from the cranial portion of the uterine horn. The eCG administration induced greater serum estradiol-17ß concentrations before ovulation (P < 0.05) and greater proportion of heifers bearing a competent corpus luteum after ovulation (P = 0.054). Delaying GnRH administration from 48 h to 72 h induced a longer interval from device removal to ovulation (i.e., prolonged proestrus; P < 0.05), larger diameter of the ovulatory follicle, and greater progesterone concentrations on Day 10-11 after ovulation. Heifers in eCG + GnRH72h group had more uterine receptors in luminal epithelium than those in eCG + GnRH48h group (PR and ERα), and than those in No eCG + GnRH72h group (PR) (P < 0.05). No effect of eCG or GnRH treatments was found in endometrial gene expression of progesterone and estrogen receptors. In Experiment 2, a total of 2,598 heifers received the J-Synch protocol associated or not with eCG administration at device removal, followed by FTAI/GnRH at 60 or 72 h after device removal (i.e., prolonged proestrus protocol). Heifers that received eCG had greater P/AI than those not receiving eCG (P < 0.05) and there was an interaction between eCG treatment and time of FTAI. The lowest P/AI was found in those heifers that received FTAI/GnRH at 72 h without eCG treatment at device removal (P < 0.05), and no differences were found between the other experimental groups. In conclusion, prolonging the length of proestrus in J-Synch protocol improves ovulatory follicular diameter and luteal function; and the administration of eCG at device removal improves preovulatory estradiol concentrations and luteal function. Finally, P/AI was enhanced by eCG treatment and the improvement was more evident when FTAI/GnRH was performed at 72 h after device removal.


Assuntos
Bovinos , Gonadotropina Coriônica/farmacologia , Ovulação/efeitos dos fármacos , Útero/efeitos dos fármacos , Animais , Sincronização do Estro/métodos , Feminino , Inseminação Artificial/veterinária , Folículo Ovariano/efeitos dos fármacos , Indução da Ovulação/veterinária , Gravidez , Taxa de Gravidez , Útero/fisiologia
16.
Clin Transl Oncol ; 22(8): 1205-1215, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31898053

RESUMO

Over the last 2 decades, the standard fluoropyrimidine-based chemotherapy backbone for metastatic colorectal cancer has been complemented by the addition of novel biological agents, achieving impressive increases in 5-year survival rates. Nonetheless, these new combinations have also entailed increases in toxicity, leading to evaluation of de-escalated chemotherapy regimens and "drug holiday" periods in attempts to reduce side effects and optimise quality of life without impairing efficacy. Here, we review the current and emerging evidence for maintenance schedules with chemotherapy and targeted agents, versus continuous treatment after induction treatment, in metastatic colorectal cancer patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Quimioterapia de Manutenção/métodos , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Bevacizumab/administração & dosagem , Camptotecina/administração & dosagem , Camptotecina/análogos & derivados , Capecitabina/administração & dosagem , Cetuximab/administração & dosagem , Ensaios Clínicos como Assunto , Neoplasias Colorretais/patologia , Progressão da Doença , Cloridrato de Erlotinib/administração & dosagem , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Humanos , Quimioterapia de Indução , Irinotecano/administração & dosagem , Leucovorina/administração & dosagem , Leucovorina/efeitos adversos , Doenças do Sistema Nervoso/induzido quimicamente , Doenças do Sistema Nervoso/prevenção & controle , Compostos Organoplatínicos/administração & dosagem , Compostos Organoplatínicos/efeitos adversos , Oxaliplatina/administração & dosagem , Oxaliplatina/efeitos adversos , Oxaloacetatos/administração & dosagem , Panitumumabe/administração & dosagem , Suspensão de Tratamento
17.
Trends Cell Biol ; 8(4): 163-7, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9695831

RESUMO

How cells generate and orientate polarized growth is of fundamental importance to understanding cell morphogenesis. The budding yeast Saccharomyces cerevisiae and the distantly related fission yeast Schizosaccharomyces pombe have both been used for genetic analysis of cell morphogenesis. Generation and maintenance of their cell shape require the formation of polarized growth sites and the correct localization of these growth sites on the cell surface with respect to other cellular structures. In this review, the authors discuss and compare the mechanisms used by the two yeasts to achieve polarized growth.


Assuntos
Polaridade Celular/fisiologia , Saccharomyces cerevisiae/fisiologia , Schizosaccharomyces/fisiologia , Polaridade Celular/genética , Genes Fúngicos , Mutação , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/genética , Schizosaccharomyces/citologia , Schizosaccharomyces/genética
18.
J Cell Biol ; 131(6 Pt 1): 1529-38, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8522609

RESUMO

To identify new genes involved in the control of cell morphogenesis in the fission yeast Schizosaccharomyces pombe we have visually screened for temperature-sensitive mutants that show defects in cell morphology. We have isolated and characterized 64 mutants defining 19 independent genes, 10 of which have not been previously described. One class of mutants, defining 12 orb genes, become round and show a complete loss of cell polarity. A second class of mutants exhibits branched or bent morphologies. These mutants show defects in either selection of the growth site, defining two tea genes, or in the maintenance of growth direction, defining five ban genes. Immunofluorescence analysis of these morphological mutants shows defects in the organization of the microtubule and actin cytoskeleton. These defects include shortened, bundled, and asymmetrically localized microtubules and enlarged and mislocalized actin patches. Analysis of the mutant phenotypes has allowed us to order the genes into four groups according to their function during the cell cycle: genes required for the maintenance of cell polarity throughout the cell cycle; genes necessary only for the reestablishment of cell polarity after mitosis and not for maintaining cell polarity once it is established; genes essential for the transition from monopolar to bipolar growth and genes that severe as 'polarity markers'.


Assuntos
Ciclo Celular/genética , Schizosaccharomyces/genética , Actinas/genética , Divisão Celular/genética , Polaridade Celular/genética , Citoesqueleto/genética , Genes Fúngicos/fisiologia , Microtúbulos/genética , Mitose/genética , Morfogênese/genética , Mutação/fisiologia , Schizosaccharomyces/citologia , Temperatura
19.
J Cell Biol ; 151(1): 15-28, 2000 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-11018050

RESUMO

Cytoplasmic microtubules are critical for establishing and maintaining cell shape and polarity. Our investigations of kinesin-like proteins (klps) and morphological mutants in the fission yeast Schizosaccharomyces pombe have identified a kinesin-like gene, tea2(+), that is required for cells to generate proper polarized growth. Cells deleted for this gene are often bent during exponential growth and initiate growth from improper sites as they exit stationary phase. They have a reduced cytoplasmic microtubule network and display severe morphological defects in genetic backgrounds that produce long cells. The tip-specific marker, Tea1p, is mislocalized in both tea2-1 and tea2Delta cells, indicating that Tea2p function is necessary for proper localization of Tea1p. Tea2p is localized to the tips of the cell and in a punctate pattern within the cell, often coincident with the ends of cytoplasmic microtubules. These results suggest that this kinesin promotes microtubule growth, possibly through interactions with the microtubule end, and that it is important for establishing and maintaining polarized growth along the long axis of the cell.


Assuntos
Polaridade Celular/genética , Genes Fúngicos , Proteínas Associadas aos Microtúbulos/genética , Microtúbulos/ultraestrutura , Proteínas de Saccharomyces cerevisiae , Proteínas de Schizosaccharomyces pombe , Schizosaccharomyces/genética , Sequência de Aminoácidos , Compartimento Celular , Clonagem Molecular , Proteínas Fúngicas/genética , Proteínas Motores Moleculares , Dados de Sequência Molecular , Biossíntese de Proteínas , Saccharomyces cerevisiae , Schizosaccharomyces/citologia , Schizosaccharomyces/crescimento & desenvolvimento , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Transcrição Gênica
20.
Science ; 166(3901): 122-3, 1969 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-5809587

RESUMO

Phosphonomycin is a newly discovered antibiotic produced by streptomycetes. It is effective, when administered by the oral route, to mice infected with Gram-positive or Gram-negative microorganisms. The antibiotic is bactericidal and inhibits cell-wall synthesis.


Assuntos
Antibacterianos/uso terapêutico , Infecções/tratamento farmacológico , Streptomyces/metabolismo , Animais , Antibacterianos/biossíntese , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Parede Celular/efeitos dos fármacos , Camundongos
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