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1.
Proc Natl Acad Sci U S A ; 119(4)2022 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-35058364

RESUMEN

While there have been recent improvements in reducing bycatch in many fisheries, bycatch remains a threat for numerous species around the globe. Static spatial and temporal closures are used in many places as a tool to reduce bycatch. However, their effectiveness in achieving this goal is uncertain, particularly for highly mobile species. We evaluated evidence for the effects of temporal, static, and dynamic area closures on the bycatch and target catch of 15 fisheries around the world. Assuming perfect knowledge of where the catch and bycatch occurs and a closure of 30% of the fishing area, we found that dynamic area closures could reduce bycatch by an average of 57% without sacrificing catch of target species, compared to 16% reductions in bycatch achievable by static closures. The degree of bycatch reduction achievable for a certain quantity of target catch was related to the correlation in space and time between target and bycatch species. If the correlation was high, it was harder to find an area to reduce bycatch without sacrificing catch of target species. If the goal of spatial closures is to reduce bycatch, our results suggest that dynamic management provides substantially better outcomes than classic static marine area closures. The use of dynamic ocean management might be difficult to implement and enforce in many regions. Nevertheless, dynamic approaches will be increasingly valuable as climate change drives species and fisheries into new habitats or extended ranges, altering species-fishery interactions and underscoring the need for more responsive and flexible regulatory mechanisms.


Asunto(s)
Explotaciones Pesqueras , Conservación de los Recursos Naturales , Ecosistema , Oceanografía
2.
Anticancer Drugs ; 30(8): 828-837, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-30932944

RESUMEN

Acute leukemias are a heterogeneous group of aggressive malignant neoplasms associated with severe morbidities due to the nonselectivity of current chemotherapeutic drugs to nonmalignant cells. The investigation of novel natural and synthetic structures that might be used for the development of new drugs with greater efficiency and selectivity to leukemic cells is mandatory. In this context, thiosemicarbazones have been well described in the literature by their several biological properties and their reaction is known as versatile, low-cost, and highly chemoselective. With this perspective, this study aimed to investigate the cytotoxic effect and the main death mechanisms of a novel thiosemicarbazone (LAP17) on acute leukemia cell lines K562 and Jurkat. The results show that the strong cytotoxic effect of LAP17 to leukemic cells is due to apoptosis induction, which resulted in caspase-3 activation and DNA fragmentation. Intrinsic apoptosis seems to be related to the inversion of Bax/Bcl-2 expression, ΔΨm loss, and AIF release, whereas extrinsic apoptosis was initiated by FasR. Gene-expression profiling of HL-60 cells treated with LAP17 by the microarray technique revealed a significant enrichment of gene sets related to cell cycle arrest at G2/M. Accordingly, K562 and Jurkat cells treated with LAP17 revealed a clear arrest at G2/M phase. Taking into consideration that LAP17 was not cytotoxic to nonhematological cells (peripheral blood mononuclear cell and erythrocytes), these results suggest that LAP17 is a promising new compound that might be used as a prototype for the development of new antileukemic agents.


Asunto(s)
Antineoplásicos/farmacología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucocitos Mononucleares/efectos de los fármacos , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Tiosemicarbazonas/química , Antineoplásicos/química , Apoptosis , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Ciclo Celular , Proliferación Celular , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patología , Potencial de la Membrana Mitocondrial , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Células Tumorales Cultivadas
3.
Bioorg Med Chem ; 26(21): 5742-5750, 2018 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-30389409

RESUMEN

Mycobacterium tuberculosis secretes two protein tyrosine phosphatases as virulence factors, PtpA and PtpB. Inhibition studies of these enzymes have shown significant attenuation of the M. tuberculosis growth in vivo. As PtpA mediates many effects on the regulation of host signaling ensuring the intracellular survival of the bacterium we report, for the first time, thiosemicarbazones as potential novel class of PtpA inhibitors. Several compounds were synthesized and biologically evaluated, revealing interesting results. Enzyme kinetic assays showed that compounds 5, 9 and 18 are non-competitive inhibitors of PtpA, with Ki values ranging from 1.2 to 5.6 µM. Modeling studies clarified the structure-activity relationships observed in vitro and indicated a possible allosteric binding site in PtpA structure. To the best of our knowledge, this is the first disclosure of potent non-competitive inhibitors of PtpA with great potential for future studies and development of analogues.


Asunto(s)
Antituberculosos/farmacología , Proteínas Bacterianas/antagonistas & inhibidores , Inhibidores Enzimáticos/farmacología , Mycobacterium tuberculosis/efectos de los fármacos , Proteínas Tirosina Fosfatasas/antagonistas & inhibidores , Tiosemicarbazonas/farmacología , Antituberculosos/síntesis química , Antituberculosos/química , Proteínas Bacterianas/química , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Cinética , Simulación del Acoplamiento Molecular , Estructura Molecular , Proteínas Tirosina Fosfatasas/química , Relación Estructura-Actividad , Tiosemicarbazonas/síntesis química , Tiosemicarbazonas/química
4.
J Med Entomol ; 60(4): 631-636, 2023 07 12.
Artículo en Inglés | MEDLINE | ID: mdl-37079723

RESUMEN

New World screwworm flies, Cochliomyia hominivorax (Coquerel), are obligate parasites of warm-blooded animals. They were eradicated from North and Central America during the mid-20th to early-21st centuries using the sterile insect technique (SIT), a method presently employed to maintain a permanent barrier between Central and South America. Lures are an important component of the screwworm eradication program, where they are used for surveillance, sample collection, and strain evaluation in the field. The first chemical lure, later named swormlure, was developed based on the attractiveness of C. hominivorax to volatile organic compounds (VOCs) produced from decomposing animal tissues. The formulation has changed little over the years and presently contains 10 chemicals, one of which is dimethyl disulfide (DMDS). Restrictions on the transport of DMDS have recently impeded its use in swormlure-4 (SL-4). However, dimethyl trisulfide (DMTS) is not as highly restricted and can be shipped via air transportation. Both chemicals are produced by microbial decomposition of animal tissues. Here, we conducted field trials using three releases of sterile C. hominivorax, each comprising approximately 93,000 flies, to test the efficacy of SL-4, containing DMDS, to swormlure-5 (SL-5) containing DMTS. Traps baited with SL-4 and SL-5 captured 575 (mean = 191.7, SD 17.9) and 665 (mean = 221.7, SD 33.2) C. hominivorax, respectively (df = 19, F = 1.294, P = 0.269). However, traps baited with SL-5 captured considerably more Cochliomyia macellaria (Fabricius), a closely related but nontarget fly.


Asunto(s)
Dípteros , Compuestos Orgánicos Volátiles , Animales , Animales Domésticos , Calliphoridae
5.
Plast Reconstr Surg Glob Open ; 10(1): e4073, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35186628

RESUMEN

Several methods have been developed for the treatment of ptosis and breast hypertrophy, with good early results but with dissatisfaction in the long term, due to loss of volume and projection of the upper pole and recurrence of ptosis. In the face of this adversity, the purposes of the present study were to describe a surgical technique of breast reduction and mastopexy with silicone implants, named structured mammoplasty, and to present the outcomes of patients who underwent this technique. METHODS: The structured mammoplasty technique with round silicone prostheses (surgical marking and stages), performed on 100 patients who were operated on between 2017 and 2020 and were followed up for a minimum of 12 months, was described. Postoperative and patient satisfaction assessments were made. RESULTS: No major complications were observed in an average of 18 months of follow-up (ranging from 12 to 30 months). The maintenance of the outcome with a projected upper pole and rounded breasts resulted in a high level of satisfaction. CONCLUSIONS: Structured mammoplasty with silicone implants is a safe and predictable option, ensuring a long-lasting shape. It can be applied to any breast that has surplus skin, making it a more reliable option in the arsenal of the plastic surgeon.

6.
Hematol Oncol Stem Cell Ther ; 14(1): 51-64, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32763229

RESUMEN

The present study aimed to investigate the cytotoxic effect of 38 new thiosemicarbazone derivatives on hematological neoplastic cells lines and to select the most effective compounds to investigate the main molecular mechanisms involved in cell death. Cytotoxicity screening on Daudi and Jurkat cells revealed that only compound 1b met the selection criteria; therefore, it was chosen for further investigation. Cell viability of Daudi, Jurkat, Molt-4, Namalwa, K562, and MM.1S cell lines decreased in a concentration- and time-dependent manner after compound1b incubation; nevertheless the compound neither caused significant hemolysis nor reduction in peripheral blood mononuclear cell viability. Although no changes were observed on cell cycle or Ki-67 expression, compound1b induced apoptotic-like cell death with mitochondrial involvement, Bax/Bcl-2 inversion, AIF release, survivin inhibition, and caspase-3 activation in both Daudi and Jurkat cells. Furthermore, the compound reduced NFκB expression in Jurkat cells. In Daudi cells, compound1b also decreased CHOP, Akt, pAkt, and MAPK/ERK2 expression, thereby suggesting modulation of UPR, PI3K/Akt/mTOR, and MAPK/ERK signaling pathways. Finally, the compound was able to reduce the cell viability of samples collected from patients with different lymphoid neoplasms subtypes, showing that thiosemicarbazones derivatives could be used in the development of new drugs with anticancer activity.


Asunto(s)
Antineoplásicos , Citotoxinas , Leucemia , Linfoma , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Proteínas de Neoplasias/metabolismo , Tiosemicarbazonas , Antineoplásicos/síntesis química , Antineoplásicos/química , Antineoplásicos/farmacología , Muerte Celular/efectos de los fármacos , Citotoxinas/síntesis química , Citotoxinas/química , Citotoxinas/farmacología , Humanos , Células Jurkat , Células K562 , Leucemia/tratamiento farmacológico , Leucemia/metabolismo , Leucemia/patología , Linfoma/tratamiento farmacológico , Linfoma/metabolismo , Linfoma/patología , Tiosemicarbazonas/síntesis química , Tiosemicarbazonas/química , Tiosemicarbazonas/farmacología
7.
Reprod Sci ; 25(7): 1093-1105, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29025323

RESUMEN

After menopause, hypertension elevates the risk of cardiac diseases, one of the major causes of women's morbidity. The gradual depletion of ovarian follicles in rats, induced by 4-vinylcyclohexene diepoxide (VCD), is a model for studying the physiology of menopause. 4-Vinylcyclohexene diepoxide treatment leads to early ovarian failure (OF) and a hormonal profile comparable to menopause in humans. We have hypothesized that OF can compromise the balance between sympathetic and parasympathetic tones of the cardiovascular system, shifting toward dominance of the former. We aimed to study the autonomic modulation of heart and blood vessels and the cardiovascular reflexes in rats presenting short-term (80 days) or long-term (180 days) OF induced by VCD. Twenty-eight-day-old Wistar rats were submitted to VCD treatment (160 mg/kg, intraperitoneally) or vehicle (control) for 15 consecutive days and experiments were conducted at 80 or 180 days after the onset of treatment. Long-term OF led to an increase in the sympathetic activity to blood vessels and an impairment in the baroreflex control of the heart, evoked by physiological changes in arterial pressure. Despite that, long-term OF did not cause hypertension during the 180 days of exposure. Short-term OF did not cause any deleterious effect on the cardiovascular parameters analyzed. These data indicate that long-term OF does not disrupt the maintenance of arterial pressure homeostasis in rats but worsens the autonomic cardiovascular control. In turn, this can lead to cardiovascular complications, especially when associated with the aging process seen during human menopause.


Asunto(s)
Sistema Nervioso Autónomo , Fenómenos Fisiológicos Cardiovasculares , Sistema Cardiovascular/inervación , Hipertensión/fisiopatología , Folículo Ovárico/efectos de los fármacos , Perimenopausia , Animales , Presión Arterial , Ciclohexenos/administración & dosificación , Femenino , Hipertensión/etiología , Modelos Animales , Ratas Wistar , Compuestos de Vinilo/administración & dosificación
8.
Toxicon ; 110: 51-5, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26695000

RESUMEN

Harmful Trichodesmium blooms have been reported on the continental slope of the southwestern South Atlantic Ocean; we sampled six such blooms. The highest saxitoxin concentration was observed where the number of colonies was proportionally greater relative to the total density of trichomes. Trichodesmium blooms are harmful to shrimp larvae and may lead to plankton community mortality. This study is the first record of neurotoxic blooms in the open waters of the South Atlantic.


Asunto(s)
Cianobacterias/crecimiento & desarrollo , Floraciones de Algas Nocivas , Océano Atlántico , Brasil , Cianobacterias/química , Monitoreo del Ambiente , Neurotoxinas/análisis , Neurotoxinas/toxicidad , Saxitoxina/análisis , Saxitoxina/toxicidad , Análisis Espacio-Temporal
9.
Rev. homeopatia (Säo Paulo) ; 81(3/4): 16-24, 2018. tab, ilus
Artículo en Español | LILACS, HomeoIndex | ID: biblio-969657

RESUMEN

As síndromes mielodisplásicas (SMD) representam um grupo heterogêneo de doenças com ampla variação de manifestações clínica e patológicas, que têm em comum um defeito clonal nas células progenitoras (células-tronco). A patogênese da SMD ainda é pouco compreendida, uma vez que há participação de um complexo de eventos abnormais. Neste relato de caso, longitudinal e prospectivo, é apresentado o tratamento de uma paciente diagnosticada com SMD. O acompanhamento e o tratamento desta paciente foi realizado com terapêutica convencional, consistindo em transfusões sanguíneas e quelante de ferro (2003-2015) e tratamento homeopático coadjuvante (2015-2018). Foi constatada retomada da hematopoiese, evoluindo com melhora hematológica sem necessidade transfusional, com consequente suspensão do tratamento com hemotransfusão pela equipe de hematologia, 4 meses depois de iniciar a terapêutica homeopática. (AU)


Myelodysplastic syndrome (MDS) is a heterogeneous group of diseases with variable clinical and pathological manifestations having in common clonal expansion of defective hematopoietic stem cells. The pathogenesis of MDS is still poorly understood, as it involves a complex of abnormal events. In this longitudinal and prospective case report, the homeopathic treatment of a patient diagnosed with MDS is described. The patient received conventional treatment, consisting of blood transfusions and iron chelator (2003-2015) and adjuvant homeopathic treatment (2015-2018). Hematopoiesis returned to normal, and blood transfusions were discontinued by the attending hematology staff 4 months after the onset of homeopathic treatment. (AU)


Asunto(s)
Humanos , Femenino , Adulto , Síndromes Mielodisplásicos/terapia , Crotalus horridus/uso terapéutico , Ferrum/uso terapéutico , /uso terapéutico , Homeopatía
10.
Rev. homeopatia (Säo Paulo) ; 74(3,n.esp): 16-16, 2011.
Artículo en Portugués | LILACS | ID: lil-620740

RESUMEN

Introdução: A sensibilização e formação dos médicos, desde a graduação, para indicarem a homeopatia para seus pacientes é fundamental.Objetivos: Descrever a experiência de dois anos do ensino da homeopatia na enfermaria de um serviço hospitalar universitário e o desenvolvimento no aprendizado e capacitação dos discentes graduandos em medicina e em pós-graduação em homeopatia e pediatria a respeito da terapêutica homeopática, onde foi utilizada como recurso terapêutico coadjuvante, junto aos pacientes internados.


Asunto(s)
Hospitales de Enseñanza
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