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1.
Mol Biol Evol ; 40(4)2023 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-37043525

RESUMO

Termites are dominant animals of tropical terrestrial ecosystems. Their success is due to their eusocial organization as well as their ability to digest dead plant tissues. While being extremely abundant, the termite diet is poor in crucial nutrients, such as fatty acids. Linoleic acid (LA) is a precursor for many vital biomolecules, and most animals depend on its dietary supply. Termites count among the exceptions known to produce LA de novo, presumably via the action of an unknown Δ12 fatty acyl desaturase (FAD) introducing the second double bond into monounsaturated oleic acid. Here, we search for the evolutionary origin of LA biosynthesis in termites. To this end, we compile the repertoire of FAD homologs from 57 species of termites and their closest relatives, the cockroaches, analyze FAD phylogeny, and identify a potential Δ12 FAD branch, which arose through duplication of a likely Δ9 FAD. We functionally characterize both paralogs and identify the Δ9 activity in the ancestral FAD-A1a and the Δ12 activity responsible for LA biosynthesis in FAD-A1b. Through the combination of homology modeling and site-directed mutagenesis, we pinpoint structural features possibly contributing to the distinct functions, regiospecificities, and substrate preferences of the two enzymes. We confirm the presence of both paralogs in all 36 studied species of the Blattoidea lineage (Blattidae, Lamproblattidae, Cryptocercidae, and termites) and conclude that we identified an evolutionary event important for the ecological success of termites, which took place in their cockroach ancestors roughly 160 My and remained conserved throughout termite diversification into 3,000 extant species.


Assuntos
Baratas , Isópteros , Animais , Ácido Linoleico , Isópteros/genética , Ecossistema , Filogenia , Ácidos Graxos
2.
Dis Colon Rectum ; 67(1): 54-61, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37787502

RESUMO

BACKGROUND: Management of lateral pelvic lymph nodes in locally advanced rectal cancer is controversial, with limited data indicating the optimal approach. In addition, no data exist regarding the treatment of lateral nodes in the setting of short-course radiation and nonoperative intent. OBJECTIVE: To evaluate a novel approach incorporating simultaneous integrated boost to suspicious lateral nodes. DESIGN: A retrospective study. SETTING: This study was conducted at a large tertiary referral center. PATIENTS: Patients treated with radiation therapy and consolidation chemotherapy were included. All primary tumors underwent biopsy confirmation and disease staging with pelvic MRI. INTERVENTIONS: Primary tumors were biopsy proven and staged with pelvic MRI. A subset of lateral pelvic lymph node patients received a simultaneous integrated boost of 35 Gy in 5 fractions. Then, chemotherapy was administered, with the majority receiving modified folinic acid, fluorouracil, and oxaliplatin. Clinical partial response required total mesorectal excision. MAIN OUTCOME MEASURES: Patterns of failure and survival analyses by subgroup were assessed. Outcomes based on receipt of radiation were compared across node status. RESULTS: Between January 2017 and January 2022, 155 patients were treated with short-course chemotherapy, with 121 included in the final analysis. Forty-nine percent of patients underwent nonoperative management. The median follow-up was 36 months and the median age was 58 years. Thirty-eight patients (26%) had positive lateral pelvic lymph nodes. Comparing lateral node status, progression-free survival was significantly worse for patients with positive disease ( p < 0.001), with a trend for worse overall survival. Receipt of nodal boost in patients with lateral nodes resulted in meaningful locoregional control. Nodal boost did not contribute to additional acute or late GI toxicity. LIMITATIONS: Limitations include retrospective nature and lack of lateral node pathology; however, a thorough radiographic review was performed. CONCLUSIONS: Lateral node-positive rectal cancer is correlated with worse oncologic outcomes and higher locoregional failure. Boost to clinically positive lateral nodes is a safe approach in the setting of short course radiation and in those receiving nonoperative intent. See Video Abstract. MANEJO DE LOS GANGLIOS PLVICOS LATERALES Y PATRONES DE FALLA EN PACIENTES QUE RECIBEN RADIACIN DE CICLO CORTO PARA EL CNCER DE RECTO LOCALMENTE AVANZADO: ANTECEDENTES:El manejo de los ganglios linfáticos pélvicos laterales en el cáncer de recto localmente avanzado es controvertido, con datos limitados que indiquen el abordaje óptimo. Además, no existen datos sobre el tratamiento de los ganglios linfáticos laterales en el contexto de la radiación de curso corto y la intención no operatoria.OBJETIVO:Evaluamos un enfoque novedoso que incorpora sobreimpresión integrada simultánea (SIB) a los linfonodos laterales sospechosos.DISEÑO:Este fue un estudio retrospectivo.ESCENARIO:Este estudio se realizó en un gran centro de referencia terciario.PACIENTES:Se incluyeron pacientes tratados con radiación y quimioterapia de consolidación. Todos los tumores primarios se confirmaron mediante biopsia y la enfermedad se estadificó con resonancia magnética pélvica.INTERVENCIONES:Los tumores primarios se confirmaron mediante biopsia y se estadificaron con RM pélvica. Un subconjunto de pacientes con linfonodos pélvicos laterales (LPLN) recibió SIB a 35 Gy en 5 fracciones. Luego, se administró quimioterapia y la mayoría recibió mFOLFOX. La respuesta clínica parcial requirió la escisión total del mesorrecto.PRINCIPALES MEDIDAS DE RESULTADO:Se evaluaron los patrones de fracaso y los análisis de supervivencia por subgrupo. Los resultados basados en el esquema de radiación se compararon según el estado de los ganglios.RESULTADOS:Entre enero de 2017 y enero de 2022, 155 pacientes fueron tratados con ciclo corto y quimioterapia con 121 incluidos en el análisis final. El 49% se sometió a manejo no operatorio. La mediana de seguimiento fue de 36 meses y la mediana de edad fue de 58 años. 38 pacientes (26%) tuvieron LPLN positivos. Comparando el estado de los ganglios laterales, la supervivencia libre de progresión fue significativamente peor para los pacientes con LPLN positiva ( p < 0,001) con una tendencia a una peor supervivencia global. La recepción de refuerzo nodal en pacientes con nodos laterales dio como resultado un control locorregional significativo. La sobreimpresión ganglionar no contribuyó a la toxicidad GI aguda o tardía adicional.LIMITACIONES:Las limitaciones incluyeron la naturaleza retrospectiva y la falta de patología de los ganglios linfáticos laterales; sin embargo, se realizó una revisión radiográfica exhaustiva.CONCLUSIONES:El cáncer de recto con ganglio lateral positivo se correlaciona con peores resultados oncológicos y mayor fracaso locorregional. La sobreimpresión a los ganglios laterales clínicamente positivos es un enfoque seguro en el contexto de un curso corto y en aquellos que siguen un manejo no operatorio. (Traducción-Dr. Felipe Bellolio ).


Assuntos
Segunda Neoplasia Primária , Neoplasias Retais , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Pelve , Neoplasias Retais/radioterapia , Linfonodos , Estadiamento de Neoplasias
3.
Int J Mol Sci ; 25(11)2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38892311

RESUMO

Plants and insects coevolved as an evolutionarily successful and enduring association. The molecular arms race led to evolutionary novelties regarding unique mechanisms of defence and detoxification in plants and insects. While insects adopt mechanisms to conquer host defence, trees develop well-orchestrated and species-specific defence strategies against insect herbivory. However, current knowledge on the molecular underpinnings of fine-tuned tree defence responses against different herbivore insects is still restricted. In the current study, using a multi-omics approach, we unveiled the defence response of Populus tremula against aphids (Chaitophorus populialbae) and spongy moths (Lymantria dispar) herbivory. Comparative differential gene expression (DGE) analyses revealed that around 272 and 1203 transcripts were differentially regulated in P. tremula after moth and aphid herbivory compared to uninfested controls. Interestingly, 5716 transcripts were differentially regulated in P. tremula between aphids and moth infestation. Further investigation showed that defence-related stress hormones and their lipid precursors, transcription factors, and signalling molecules were over-expressed, whereas the growth-related counterparts were suppressed in P. tremula after aphid and moth herbivory. Metabolomics analysis documented that around 37% of all significantly abundant metabolites were associated with biochemical pathways related to tree growth and defence. However, the metabolic profiles of aphid and moth-fed trees were quite distinct, indicating species-specific response optimization. After identifying the suitable reference genes in P. tremula, the omics data were further validated using RT-qPCR. Nevertheless, our findings documented species-specific fine-tuning of the defence response of P. tremula, showing conservation on resource allocation for defence overgrowth under aphid and moth herbivory. Such findings can be exploited to enhance our current understanding of molecular orchestration of tree responses against herbivory and aid in developing insect pest resistance P. tremula varieties.


Assuntos
Afídeos , Regulação da Expressão Gênica de Plantas , Herbivoria , Mariposas , Populus , Transcriptoma , Populus/genética , Populus/parasitologia , Populus/metabolismo , Animais , Afídeos/fisiologia , Mariposas/fisiologia , Mariposas/genética , Metabolômica/métodos , Perfilação da Expressão Gênica , Metaboloma
4.
J Assoc Physicians India ; 72(6): 15-19, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38881128

RESUMO

BACKGROUND: The modified Ponticelli regimen (mPR) is a first-line therapy in patients with idiopathic membranous nephropathy (IMN); however, it has a less favorable safety profile. Though mycophenolate mofetil (MMF) + steroid (S) is not recommended by Kidney Disease Improving Global Outcomes guidelines, it can be used as an alternative to mPR due to higher tolerability and steroid-sparing effect. Thus, we compared the safety and effectiveness of MMF + S and mPR regimens in patients with IMN. METHODS: This randomized, open-label study enrolled patients with adult-onset nephrotic syndrome (NS) and biopsy-proven IMN. Forty-two patients were allocated to MMF + S group (MMF 1 gm twice daily + oral prednisolone 0.5 mg/kg/day; n = 21) and mPR group [methylprednisolone (1 gm intravenous) for 3 days followed by alternating monthly cycles of oral prednisolone (0.5 mg/kg/day) for the next 27 days and cyclophosphamide (2 mg/kg/day) for 6 months; n = 21]. The primary outcome measure was change in urinary protein creatinine ratio (UPCR). RESULTS: At 6 months, both groups demonstrated a significant increase in serum albumin levels and estimated glomerular filtration rate (eGFR) (both p-values <0.0001) as well as a decrease in 24-hour proteinuria (MMF + S group: p-value = 0.003, and mPR group: p-value <0.0001) and UPCR (both p-values <0.0001). However, the groups did not differ in any of these parameters at any of the monthly follow-up visits. Moreover, the groups did not differ significantly in terms of the composite remission rates (61.91% for MMF + S group and 71.43% for mPR group). CONCLUSION: MMF + S and mPR had comparable tolerability and effectiveness, with MMF-associated advantage of reduced steroid exposure.


Assuntos
Quimioterapia Combinada , Glomerulonefrite Membranosa , Imunossupressores , Ácido Micofenólico , Prednisolona , Humanos , Glomerulonefrite Membranosa/tratamento farmacológico , Ácido Micofenólico/uso terapêutico , Ácido Micofenólico/administração & dosagem , Masculino , Feminino , Adulto , Imunossupressores/administração & dosagem , Imunossupressores/uso terapêutico , Prednisolona/administração & dosagem , Prednisolona/uso terapêutico , Pessoa de Meia-Idade , Glucocorticoides/administração & dosagem , Glucocorticoides/uso terapêutico , Ciclofosfamida/uso terapêutico , Ciclofosfamida/administração & dosagem , Metilprednisolona/administração & dosagem , Metilprednisolona/uso terapêutico , Resultado do Tratamento
5.
J Theor Biol ; 572: 111589, 2023 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-37532028

RESUMO

The renin-angiotensin systems play pivotal role in cardiovascular physiology through its effects on regulating blood pressure and electrolyte homeostasis. Components of circulating RAS (cRAS) that include precursor angiotensinogen, two critical enzymes (renin and angiotensin-converting enzyme, ACE), their bioactive products, angiotensin- I, II together with its receptors (AT1R and AT2R) essentially determine this homeostasis. Most classical studies, however, showed the deleterious role of cRAS in elevating the blood pressure. Contemporary discovery of non-canonical components of the RAS has challenged this classic hypothesis that it can only exert deleterious effects on the cardiovascular systems. Using the classic cRAS model, we have designed in-silico experiments to test the hypothesis that AT2R-mediated feedback effects play pivotal role for maintaining the normal variation of the mean-arterial pressure (MAP).Beside the AT2R-mediation of downstream singling pathways consisting of several non-canonical RAS components, this study first time illustrated AT2R mediated feedback controls over the blood pressure regulation: one that impedes AT1R activity, and the other that downregulates renin. It has been shown that relatively stronger suppression of renin activity significantly contributes in maintaining the normal MAP and that tight AT2R-mediated regulation is relaxed in hyper-and hypotension. This control mechanism is noted to be robustly maintained with the MAP variations through an established linear steady-state relationship among renin, angiotensin I and angiotensin II. This examination suggests that AT2R-mediated downregulation of renin activities potentially counteracts the AT1R-mediated deleterious actions of Ang II. This study, therefore, provides a solid ground for considering different AT2 receptor adaptor protein and direct agonism at AT2R that can cause greater effects along with contemporary approaches of blocking AT1R mediation to attenuate hypertension or other cardiovascular disorders.


Assuntos
Pressão Arterial , Renina , Renina/metabolismo , Retroalimentação , Sistema Renina-Angiotensina/fisiologia , Angiotensina II/metabolismo
6.
Ecotoxicol Environ Saf ; 255: 114783, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36963184

RESUMO

In the current scenario of global warming and climate change, plants face many biotic stresses, which restrain growth, development and productivity. Nanotechnology is gaining precedence over other means to deal with biotic and abiotic constraints for sustainable agriculture. One of nature's most beneficial metalloids, silicon (Si) shows ameliorative effect against environmental challenges. Silicon/Silica nanoparticles (Si/SiO2NPs) have gained special attention due to their significant chemical and optoelectronic capabilities. Its mesoporous nature, easy availability and least biological toxicity has made it very attractive to researchers. Si/SiO2NPs can be synthesised by chemical, physical and biological methods and supplied to plants by foliar, soil, or seed priming. Upon uptake and translocation, Si/SiO2NPs reach their destined cells and cause optimum growth, development and tolerance against environmental stresses as well as pest attack and pathogen infection. Using Si/SiO2NPs as a supplement can be an eco-friendly and cost-effective option for sustainable agriculture as they facilitate the delivery of nutrients, assist plants to mitigate biotic stress and enhances plant resistance. This review aims to present an overview of the methods of formulation of Si/SiO2NPs, their application, uptake, translocation and emphasize the role of Si/SiO2NPs in boosting growth and development of plants as well as their conventional advantage as fertilizers with special consideration on their mitigating effects towards biotic stress.


Assuntos
Nanopartículas , Silício , Silício/farmacologia , Plantas , Estresse Fisiológico , Agricultura , Nanopartículas/toxicidade
7.
Int J Mol Sci ; 24(11)2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37298113

RESUMO

The spotted bollworm Earias vittella (Lepidoptera: Nolidae) is a polyphagous pest with enormous economic significance, primarily affecting cotton and okra. However, the lack of gene sequence information on this pest has a significant constraint on molecular investigations and the formulation of superior pest management strategies. An RNA-seq-based transcriptome study was conducted to alleviate such limitations, and de novo assembly was performed to obtain transcript sequences of this pest. Reference gene identification across E. vittella developmental stages and RNAi treatments were conducted using its sequence information, which resulted in identifying transcription elongation factor (TEF), V-type proton ATPase (V-ATPase), and Glyceraldehyde -3-phosphate dehydrogenase (GAPDH) as the most suitable reference genes for normalization in RT-qPCR-based gene expression studies. The present study also identified important developmental, RNAi pathway, and RNAi target genes and performed life-stage developmental expression analysis using RT-qPCR to select the optimal targets for RNAi. We found that naked dsRNA degradation in the E. vittella hemolymph is the primary reason for poor RNAi. A total of six genes including Juvenile hormone methyl transferase (JHAMT), Chitin synthase (CHS), Aminopeptidase (AMN), Cadherin (CAD), Alpha-amylase (AMY), and V-type proton ATPase (V-ATPase) were selected and knocked down significantly with three different nanoparticles encapsulated dsRNA conjugates, i.e., Chitosan-dsRNA, carbon quantum dots-dsRNA (CQD-dsRNA), and Lipofectamine-dsRNA conjugate. These results demonstrate that feeding nanoparticle-shielded dsRNA silences target genes and suggests that nanoparticle-based RNAi can efficiently manage this pest.


Assuntos
Mariposas , Nanopartículas , Animais , Interferência de RNA , Prótons , Mariposas/genética , RNA de Cadeia Dupla/genética , Adenosina Trifosfatases
8.
J Environ Manage ; 331: 117264, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36634422

RESUMO

Empirical evidence supporting the associations between malaria incidence and climatic factors has remained controversial, buffering the progress in the Global Malaria Program that aims to eliminate 90% of the world malaria burden by 2030. This study has aimed to evaluate the nature and extent at which these relations are maintained across all the malaria endemic countries of Africa and Asia-Pacific region. We have utilized the last two decades of malaria incidence, annual minimum temperature, and annual precipitation time series data (2000-2020) for the two most malaria-impacted regions. These data were fitted in the generalized linear model and the mixed effects model. The results showed that there exists a large heterogeneity in malaria incidence across the countries, and between the regions. Last two decadal tendencies showed significant reductions in the disease burden in almost all the countries in the Asia Pacific, with several exceptions or relatively slowed reductions in the Africa. We found significant changes in the positive linear associations between malaria incidence, annual minimum temperature, and annual precipitation across African countries. Many Asia-Pacific countries namely Bangladesh, Bhutan, Indonesia, South Korea, Nepal, Thailand, Vietnam showed negative effects in the associations with the annual precipitation. This study indicates that increasing temperature within the range of 12-30 °C can generate positive effects on malaria incidence, but the nature and extent of precipitation effects vary across countries and at a large regional scale.


Assuntos
Malária , Humanos , Incidência , Malária/epidemiologia , Indonésia , Tailândia , África/epidemiologia
9.
Ecol Lett ; 25(8): 1746-1759, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35726578

RESUMO

Pesticide resistance development is an example of rapid contemporary evolution that poses immense challenges for agriculture. It typically evolves due to the strong directional selection that pesticide treatments exert on herbivorous arthropods. However, recent research suggests that some species are more prone to evolve pesticide resistance than others due to their evolutionary history and standing genetic variation. Generalist species might develop pesticide resistance especially rapidly due to pre-adaptation to handle a wide array of plant allelochemicals. Moreover, research has shown that adaptation to novel host plants could lead to increased pesticide resistance. Exploring such cross-resistance between host plant range evolution and pesticide resistance development from an ecological perspective is needed to understand its causes and consequences better. Much research has, however, been devoted to the molecular mechanisms underlying pesticide resistance while both the ecological contexts that could facilitate resistance evolution and the ecological consequences of cross-resistance have been under-studied. Here, we take an eco-evolutionary approach and discuss circumstances that may facilitate cross-resistance in arthropods and the consequences cross-resistance may have for plant-arthropod interactions in both target and non-target species and species interactions. Furthermore, we suggest future research avenues and practical implications of an increased ecological understanding of pesticide resistance evolution.


Assuntos
Artrópodes , Praguicidas , Animais , Artrópodes/genética , Evolução Biológica , Herbivoria , Resistência a Inseticidas/genética , Plantas
10.
Am J Med Genet A ; 188(10): 3009-3015, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36097643

RESUMO

Neurofibromatosis type 1 (NF1) is associated with a range of vascular abnormalities. To assess the frequency, clinical and imaging spectrum of vascular complications in an adult cohort of NF1 patients, we reviewed 2068 adult NF1 patient records seen in our service between 2009 and 2019, to determine presence of vascular abnormalities, age at detection, associated symptoms and management. A literature review of the range of vascular abnormalities associated with NF1 was also undertaken. 1234 patients had magnetic resonance imaging cranial imaging. The frequency of vascular abnormalities associated with NF1 patients who had cranial imaging in this cohort was 3.5% (n = 43), the majority (n = 26, 60%) were symptomatic. Stroke and cerebral arterial stenosis were the commonest vascular complication. Eight patients (0.65%) had more than one type of vascular abnormality. One death due to a vascular complication was identified and significant morbidity resulted from other complications. We conclude that clinicians caring for patients with NF1 need to be cognizant that rapid onset of new neurological symptoms or signs may be the result of a vascular complication of NF1 and require urgent investigation and management, ideally within specialist teams who have experience of managing vascular complications of NF1.


Assuntos
Anormalidades Cardiovasculares , Neurofibromatose 1 , Doenças Vasculares , Adulto , Anormalidades Cardiovasculares/complicações , Humanos , Imageamento por Ressonância Magnética , Neurofibromatose 1/complicações , Neurofibromatose 1/diagnóstico , Neurofibromatose 1/patologia , Encaminhamento e Consulta
11.
Dis Colon Rectum ; 65(2): 198-206, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34990423

RESUMO

BACKGROUND: Short-course radiation followed by chemotherapy as total neoadjuvant therapy has been investigated primarily in Europe and Australia with increasing global acceptance. There are limited data on this regimen's use in the United States, however, potentially delaying implementation. OBJECTIVE: This study aimed to compare clinical performance and oncologic outcomes of 2 rectal cancer neoadjuvant treatment modalities: short-course total neoadjuvant therapy versus standard chemoradiation. DESIGN: This is a retrospective cohort study. SETTING: This study was performed at a National Cancer Institute-designated cancer center. PATIENTS: A total of 413 patients had locally advanced rectal cancers diagnosed from June 2009 to May 2018 and received either short-course total neoadjuvant therapy or standard chemoradiation. INTERVENTIONS: There were 187 patients treated with short-course total neoadjuvant therapy (5 × 5 Gy radiation followed by consolidation oxaliplatin-based chemotherapy) compared with 226 chemoradiation recipients (approximately 50.4 Gy radiation in 28 fractions with concurrent fluorouracil equivalent). MAIN OUTCOME MEASURES: Primary end points were tumor downstaging, measured by complete response and "low" neoadjuvant rectal score rates, and progression-free survival. Secondary analyses included treatment characteristics and completion, sphincter preservation, and recurrence rates. RESULTS: Short-course total neoadjuvant therapy was associated with higher rates of complete response (26.2% vs 17.3%; p = 0.03) and "low" neoadjuvant rectal scores (40.1% vs 25.7%; p < 0.01) despite a higher burden of node-positive disease (78.6% vs 68.9%; p = 0.03). Short-course recipients also completed trimodal treatment more frequently (88.4% vs 50.4%; p < 0.01) and had fewer months with temporary stomas (4.8 vs 7.0; p < 0.01). Both regimens achieved comparable local control (local recurrence: 2.7% short-course total neoadjuvant therapy vs 2.2% chemoradiation, p = 0.76) and 2-year progression-free survival (88.2% short-course total neoadjuvant therapy (95% CI, 82.9-93.5) vs 85.6% chemoradiation (95% CI, 80.5-90.7)). LIMITATIONS: Retrospective design, unbalanced disease severity, and variable dosing of neoadjuvant consolidation chemotherapy were limitations of this study. CONCLUSIONS: Short-course total neoadjuvant therapy was associated with improved downstaging and similar progression-free survival compared with chemoradiation. These results were achieved with shortened radiation courses, improved treatment completion, and less time with diverting ostomies. Short-course total neoadjuvant therapy is an optimal regimen for locally advanced rectal cancer. See Video Abstract at http://links.lww.com/DCR/B724.TERAPIA NEOADYUVANTE TOTAL CON RADIACIÓN DE CORTA DURACIÓN: EXPERIENCIA ESTADOUNIDENSE DE UNA TERAPIA NEOADYUVANTE CONTRA EL CÁNCER DE RECTO. ANTECEDENTES: La radiación de corta duración seguida de quimioterapia como terapia neoadyuvante total se ha investigado principalmente en Europa y Australia con una aceptación mundial cada vez mayor. Sin embargo, datos limitados sobre el uso de este régimen en los Estados Unidos, han potencialmente retrasando su implementación. OBJETIVO: Comparar el desempeño clínico y los resultados oncológicos de dos modalidades de tratamiento neoadyuvante del cáncer de recto: terapia neoadyuvante total de corta duración versus quimioradiación. estándar. DISEO: Cohorte retrospectivo. AJUSTE: Centro oncológico designado por el NCI. PACIENTES: Un total de 413 cánceres rectales localmente avanzados diagnosticados entre junio de 2009 y mayo de 2018 que recibieron cualquiera de los regímenes neoadyuvantes. INTERVENCIONES: Hubo 187 pacientes tratados con terapia neoadyuvante total de ciclo corto (radiación 5 × 5 Gy seguida de quimioterapia de consolidación basada en oxaliplatino) en comparación con 226 pacientes de quimiorradiación (aproximadamente 50,4 Gy de radiación en 28 fracciones con equivalente de fluorouracilo concurrente). PRINCIPALES MEDIDAS DE RESULTADO: Los criterios primarios de valoración fueron la disminución del estadio del tumor, medido por la respuesta completa y las tasas de puntuación rectal neoadyuvante "baja", y la supervivencia libre de progresión. Los análisis secundarios incluyeron las características del tratamiento y las tasas de finalización, conservación del esfínter y recurrencia. RESULTADOS: La terapia neoadyuvante total de corta duración, se asoció con tasas más altas de respuesta completa (26,2% versus 17,3%, p = 0,03) y puntuaciones rectales neoadyuvantes "bajas" (40,1% versus 25,7%, p < 0,01) a pesar de una mayor carga de enfermedad con ganglios positivos (78,6% versus 68,9%, p = 0,03). Los pacientes de ciclo corto también completaron el tratamiento trimodal con mayor frecuencia (88,4% versus 50,4%, p < 0,01) y tuvieron menos meses con estomas temporales (4,8 versus 7,0, p < 0,01). Ambos regímenes lograron un control local comparable (recidiva local: 2,7% de SC-TNT versus 2,2% de TRC, p = 0,76) y supervivencia libre de progresión a 2 años (88,2% de SC-TNT [IC: 82,9 - 93,5] versus 85,6% CRT [CI: 80,5 - 90,7]). LIMITACIONES: Diseño retrospectivo, gravedad de la enfermedad desequilibrada y dosificación variable de quimioterapia neoadyuvante de consolidación. CONCLUSIONES: La terapia neoadyuvante total de ciclo corto se asoció con una mejora en la reducción del estadio y una supervivencia libre de progresión similar en comparación con la quimioradiación. Estos resultados se lograron con ciclos de radiación más cortos, tratamientos mejor finalizados y menos tiempo en ostomías de derivación. La terapia neoadyuvante total de corta duración es un régimen óptimo para el cáncer de recto localmente avanzado. Consulte Video Resumen en http://links.lww.com/DCR/B724. (Traducción- Dr. Fidel Ruiz Healy).


Assuntos
Adenocarcinoma/terapia , Quimiorradioterapia , Terapia Neoadjuvante , Protectomia , Neoplasias Retais/terapia , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Retais/mortalidade , Neoplasias Retais/patologia , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento
12.
Sensors (Basel) ; 22(5)2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35271104

RESUMO

Presently, lightweight devices such as mobile phones, notepads, and laptops are widely used to access the Internet throughout the world; however, a problem of privacy preservation and authentication delay occurs during handover operation when these devices change their position from a home mesh access point (HMAP) to a foreign mesh access point (FMAP). Authentication during handover is mostly performed through ticket-based techniques, which permit the user to authenticate itself to the foreign mesh access point; therefore, a secure communication method should be formed between the mesh entities to exchange the tickets. In two existing protocols, this ticket was not secured at all and exchanged in a plaintext format. We propose a protocol for handover authentication with privacy preservation of the transfer ticket via the Diffie-Hellman method. Through experimental results, our proposed protocol achieves privacy preservation with minimum authentication delay during handover operation.


Assuntos
Segurança Computacional , Privacidade
13.
Drug Dev Res ; 83(2): 317-327, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34962315

RESUMO

Visceral leishmaniasis (VL) or Kala-azar, is the most lethal form of leishmaniasis, is still prevalent in many countries where it is endemic. It is a threat to human life caused by protozoan parasite Leishmania donovani. The severity of the disease is further increased as the treated individuals might have a chance of developing Post Kala-azar Dermal Leishmaniasis (PKDL) in the long run. Moreover, several countries have reported high number of HIV-VL co-infected patients. Therefore, there is a dire need for the development of efficient diagnostic methods and drugs in order to combat the disease and to control the spread of disease. At present, the treatment for VL entirely relies on therapeutic drugs as no vaccine is available yet. Ever since 1900s a series of drugs have been invented and used for treatment of VL; but the need for one such cost-effective treatment that would completely cure the disease with minimal side-effects, low relapse rate with high efficacy and less toxicity remains yet to be fulfilled. Therefore, identifying novel compounds is very crucial to develop potent antileishmanial agents. Thus, this review enlists several instances of drug development, including the pharmacokinetic and pharmacodynamic properties of antileishmanial drugs, different experimental animal models used to investigate the disease progression and to analyze treatment dosage and pharmacological aspect of drugs. Furthermore, the existing gap in drug development and future measures to improve the process are also discussed in this review.


Assuntos
Antiprotozoários , Leishmania donovani , Leishmaniose Cutânea , Leishmaniose Visceral , Animais , Antiprotozoários/farmacologia , Antiprotozoários/uso terapêutico , Humanos , Leishmaniose Cutânea/tratamento farmacológico , Leishmaniose Cutânea/epidemiologia , Leishmaniose Visceral/tratamento farmacológico , Recidiva
14.
Int J Mol Sci ; 23(4)2022 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-35216108

RESUMO

With the advent of human civilization and anthropogenic activities in the shade of urbanization and global climate change, plants are exposed to a complex set of abiotic stresses. These stresses affect plants' growth, development, and yield and cause enormous crop losses worldwide. In this alarming scenario of global climate conditions, plants respond to such stresses through a highly balanced and finely tuned interaction between signaling molecules. The abiotic stresses initiate the quick release of reactive oxygen species (ROS) as toxic by-products of altered aerobic metabolism during different stress conditions at the cellular level. ROS includes both free oxygen radicals {superoxide (O2•-) and hydroxyl (OH-)} as well as non-radicals [hydrogen peroxide (H2O2) and singlet oxygen (1O2)]. ROS can be generated and scavenged in different cell organelles and cytoplasm depending on the type of stimulus. At high concentrations, ROS cause lipid peroxidation, DNA damage, protein oxidation, and necrosis, but at low to moderate concentrations, they play a crucial role as secondary messengers in intracellular signaling cascades. Because of their concentration-dependent dual role, a huge number of molecules tightly control the level of ROS in cells. The plants have evolved antioxidants and scavenging machinery equipped with different enzymes to maintain the equilibrium between the production and detoxification of ROS generated during stress. In this present article, we have focused on current insights on generation and scavenging of ROS during abiotic stresses. Moreover, the article will act as a knowledge base for new and pivotal studies on ROS generation and scavenging.


Assuntos
Plantas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Estresse Fisiológico/fisiologia , Animais , Mudança Climática , Dano ao DNA/fisiologia , Humanos , Peroxidação de Lipídeos/fisiologia , Transdução de Sinais/fisiologia
15.
Cancer Sci ; 111(2): 528-535, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31773815

RESUMO

Nivolumab 3 mg/kg every 2 weeks (Q2W) has been approved in Japan for various cancers; however, use of a flat dose is expected to simplify dosing and administration. A quantitative clinical pharmacology approach was used to assess the benefit-risk profile of nivolumab 240 mg Q2W relative to the approved dose of nivolumab 3 mg/kg Q2W in Japanese patients. Three exposure-response safety analyses were performed for adverse events that led to discontinuation/death, were grade 3 or higher, and were immune-mediated and grade 2 or higher for Japanese patients diagnosed with one of multiple tumor types. Exposure-response analyses of efficacy were evaluated for overall survival and objective response rate. Exposures of nivolumab 240 mg Q2W were 37% higher than those of nivolumab 3 mg/kg Q2W in Japanese patients across the tumor types analyzed. Predicted safety profiles at the two doses differed by less than 2% across tumor types for adverse events leading to discontinuation/death, adverse events of grade 3 or higher, or immune-mediated adverse events of grade 2 or higher. In addition, the predicted 1-year and 2-year overall survival rates, the mean overall survival and the objective response rates were comparable between the doses regardless of the tumor type analyzed. Overall, these results demonstrated that the benefit-risk of nivolumab 240 mg Q2W was comparable to that of the previously approved 3 mg/kg Q2W dosing regimen, and was the basis for the approval of the 240 mg Q2W as an alternative dosing regimen for treatment in Japanese patients across multiple tumor types.


Assuntos
Antineoplásicos Imunológicos/administração & dosagem , Neoplasias/tratamento farmacológico , Nivolumabe/administração & dosagem , Antineoplásicos Imunológicos/efeitos adversos , Antineoplásicos Imunológicos/farmacocinética , Esquema de Medicação , Cálculos da Dosagem de Medicamento , Humanos , Japão , Modelos Teóricos , Gradação de Tumores , Neoplasias/patologia , Nivolumabe/efeitos adversos , Nivolumabe/farmacocinética , Medição de Risco , Análise de Sobrevida , Resultado do Tratamento
16.
BMC Genomics ; 20(1): 428, 2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-31138111

RESUMO

BACKGROUND: Deciphering the molecular mechanisms mediating the chemical senses, taste, and smell has been of vital importance for understanding the nature of how insects interact with their chemical environment. Several gene families are implicated in the uptake, recognition, and termination of chemical signaling, including binding proteins, chemosensory receptors and degrading enzymes. The cotton leafworm, Spodoptera littoralis, is a phytophagous pest and current focal species for insect chemical ecology and neuroethology. RESULTS: We produced male and female Illumina-based transcriptomes from chemosensory and non-chemosensory tissues of S. littoralis, including the antennae, proboscis, brain and body carcass. We have annotated 306 gene transcripts from eight gene families with known chemosensory function, including 114 novel candidate genes. Odorant receptors responsive to floral compounds are expressed in the proboscis and may play a role in guiding proboscis probing behavior. In both males and females, expression of gene transcripts with known chemosensory function, including odorant receptors and pheromone-binding proteins, has been observed in brain tissue, suggesting internal, non-sensory function for these genes. CONCLUSIONS: A well-curated set of annotated gene transcripts with putative chemosensory function is provided. This will serve as a resource for future chemosensory and transcriptomic studies in S. littoralis and closely related species. Collectively, our results expand current understanding of the expression patterns of genes with putative chemosensory function in insect sensory and non-sensory tissues. When coupled with functional data, such as the deorphanization of odorant receptors, the gene expression data can facilitate hypothesis generation, serving as a substrate for future studies.


Assuntos
Proteínas de Insetos/genética , Spodoptera/genética , Animais , Antenas de Artrópodes/metabolismo , Encéfalo/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Esterases/genética , Esterases/metabolismo , Feminino , Perfilação da Expressão Gênica , Genes de Insetos , Proteínas de Insetos/metabolismo , Masculino , Família Multigênica , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Receptores Odorantes/genética , Receptores Odorantes/metabolismo , Spodoptera/enzimologia , Spodoptera/metabolismo , Spodoptera/fisiologia , Percepção Gustatória
17.
J Theor Biol ; 474: 63-77, 2019 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-30980871

RESUMO

Psoriasis is a chronic skin condition that produces plaques of condensed, scaling skin due to excessively rapid proliferation of keratinocytes. During the disease progression, keratinocyte proliferation is influenced by many immune cells and cytokines. This article deals with a five dimensional deterministic model, which has been derived using quasi-steady-state approximation for describing the dynamics of psoriasis in various cytokines environment. Equilibrium analysis of the system shows that either the system converges to a stable steady state or exhibits a periodic oscillation depending upon system parameters. Finally, introducing a one dimensional impulsive system, we have determined the perfect dose and perfect dosing interval for biologic (TNF-α inhibitor) therapy to control the hyper-proliferation of keratinocytes. We have studied the effect of TNF-α inhibitor by considering both perfect and imperfect dosing during the inductive phase. The maximum possible number of drug holidays and the minimal number of doses that must subsequently be taken while avoiding drug resistance have been calculated for imperfect dosing. Since, psoriasis is non-curable but treatable disease, so the aim is to investigate the minimum dose with highest efficacy and proper dosing interval of TNF-α inhibitor for a psoriatic patient. Through numerical simulations, we have given a detailed prediction about the maximum drug holidays, tolerable for a patient, without loss of previous drug effects. Our theoretical predictions and numerical outcomes may be useful in guiding the design of future clinical trials.


Assuntos
Citocinas/imunologia , Queratinócitos , Modelos Imunológicos , Psoríase , Fator de Necrose Tumoral alfa , Animais , Humanos , Queratinócitos/imunologia , Queratinócitos/patologia , Psoríase/tratamento farmacológico , Psoríase/imunologia , Psoríase/patologia , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/imunologia
18.
Br J Clin Pharmacol ; 85(9): 2045-2058, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31140642

RESUMO

AIMS: The development of monoclonal antibodies (mAbs) requires an understanding of the interindividual variability (IIV) in pharmacokinetics (PK) at the population level facilitated by population PK (PopPK) modelling. However, there is no clear rationale for selecting which covariates to screen during PopPK model development. Here, we compare the effect of covariates on PK parameters for mAbs in oncology and identify the most commonly used covariates affecting PK parameters. METHODS: All 25 mAbs approved for therapeutic use in oncology until December 2017 by the Food and Drug Administration and the European Medicines Agency were selected for study. Literature searches revealed 23 available PopPK models for these mAbs. To understand the magnitude and types of covariate effect on PK parameters, all covariates included in the final PopPK model for each mAb were summarized. RESULTS: The most commonly identified covariates were baseline body weight (BW; 17 mAbs), baseline serum albumin (8 mAbs), and sex (7 mAbs) on clearance; and BW (16 mAbs) and sex (12 mAbs) on central volume of distribution. A reduced PopPK model was developed for nivolumab and ipilimumab using these covariates, and the percentage of explained IIV from the reduced model (20.3% and 16.8%, respectively) was compared with that from the full model (24.5% and 27.9%, respectively). CONCLUSIONS: This analysis provides a uniform platform for selecting covariates and suggests that the effect of BW, albumin and sex should be included during the development of PopPK models for mAbs in oncology. The reduced model was able to explain IIV to a similar extent as the full model.


Assuntos
Anticorpos Monoclonais/farmacocinética , Antineoplásicos Imunológicos/farmacocinética , Variação Biológica da População , Modelos Biológicos , Neoplasias/tratamento farmacológico , Anticorpos Monoclonais/administração & dosagem , Antineoplásicos Imunológicos/administração & dosagem , Peso Corporal , Feminino , Humanos , Ipilimumab/administração & dosagem , Ipilimumab/farmacocinética , Masculino , Neoplasias/imunologia , Nivolumabe/administração & dosagem , Nivolumabe/farmacocinética , Fatores Sexuais
19.
BMC Genomics ; 19(1): 934, 2018 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-30547764

RESUMO

BACKGROUND: Epigenetic modifications including DNA methylation and post-translational modifications of histones are known to regulate gene expression. Antagonistic activities of histone acetyltransferases (HATs) and histone deacetylases (HDACs) mediate transcriptional reprogramming during insect development as shown in Drosophila melanogaster and other insects. Juvenile hormones (JH) play vital roles in the regulation of growth, development, metamorphosis, reproduction and other physiological processes. However, our current understanding of epigenetic regulation of JH action is still limited. Hence, we studied the role of CREB binding protein (CBP, contains HAT domain) and Trichostatin A (TSA, HDAC inhibitor) on JH action. RESULTS: Exposure of Tribolium castaneum cells (TcA cells) to JH or TSA caused an increase in expression of Kr-h1 (a known JH-response gene) and 31 or 698 other genes respectively. Knockdown of the gene coding for CBP caused a decrease in the expression of 456 genes including Kr-h1. Interestingly, the expression of several genes coding for transcription factors, nuclear receptors, P450 and fatty acid synthase family members that are known to mediate JH action were affected by CBP knockdown or TSA treatment. CONCLUSIONS: These data suggest that acetylation and deacetylation mediated by HATs and HDACs play an important role in JH action.


Assuntos
Epigênese Genética/efeitos dos fármacos , Ácidos Hidroxâmicos/farmacologia , Tribolium/efeitos dos fármacos , Acetilação , Animais , Proteína de Ligação a CREB/antagonistas & inibidores , Proteína de Ligação a CREB/genética , Proteína de Ligação a CREB/metabolismo , Proteínas de Insetos/antagonistas & inibidores , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Interferência de RNA , RNA de Cadeia Dupla/metabolismo , Tribolium/crescimento & desenvolvimento , Tribolium/metabolismo
20.
BMC Genomics ; 19(1): 584, 2018 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-30081819

RESUMO

Following the publication of this article [1], the authors found that the primers listed for CREB-binding protein were not correct. This mistake occurred during assembly of the primer table and the authors apologize for this error. This correction does not change the data included in the paper, their interpretation nor the conclusions drawn.

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