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1.
Actas Dermosifiliogr ; 115(2): 119-129, 2024 Feb.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-37689349

RESUMO

BACKGROUND AND OBJECTIVE: The cost of treating cutaneous T-cell lymphoma (CTCL) in Spain is unknown. With the advent of new treatments, it is more important than ever to gain an accurate picture of the true costs involved. The MICADOS study had 2 primary objectives: 1)to evaluate the impact of CTCL on patient quality of life, and 2)to evaluate the costs associated with the disease. This article reports the results of the cost analysis. METHODS: We estimated the cost of treating CTCL over a period of 1year from the perspective of the Spanish National Health System. Twenty-three dermatologists and hematologists from 15 public hospitals analyzed data for adult patients with mycosis fungoides (MF) or Sézary syndrome (SS). RESULTS: A total of 141 patients (57.4% male) with a mean age of 63.6 years (95%CI: 61.4-65.7 years) were included. The mean direct annual cost of treating CTCL was €34,214 per patient. The corresponding costs by stage were €11,952.47 for stageI disease, €23,506.21 for stageII disease, €38,771.81 for stageIII disease, and €72,748.84 for stageIV disease. The total direct annual cost of treating MF/SS in public hospitals in Spain was estimated at €78,301,171; stageI disease accounted for 81% of all costs, stageII for 7%, and stagesIII andIV for 6% each. CONCLUSIONS: The MICADOS study offers an accurate picture of the direct cost of treating CTCL in patients with MF/SS in Spain and shows that costs vary significantly according to disease stage. Patient-borne and indirect costs should be analyzed in future studies.


Assuntos
Linfoma Cutâneo de Células T , Micose Fungoide , Síndrome de Sézary , Neoplasias Cutâneas , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Qualidade de Vida , Espanha/epidemiologia , Neoplasias Cutâneas/terapia , Neoplasias Cutâneas/patologia , Linfoma Cutâneo de Células T/epidemiologia , Linfoma Cutâneo de Células T/terapia , Linfoma Cutâneo de Células T/patologia , Micose Fungoide/terapia , Micose Fungoide/patologia , Síndrome de Sézary/terapia , Síndrome de Sézary/patologia
2.
Actas Dermosifiliogr ; 115(2): T119-T129, 2024 Feb.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-38048944

RESUMO

BACKGROUND AND OBJECTIVE: The cost of treating cutaneous T-cell lymphoma (CTCL) in Spain is unknown. With the advent of new treatments, it is more important than ever to gain an accurate picture of the true costs involved. The MICADOS study had 2 primary objectives: 1)to evaluate the impact of CTCL on patient quality of life, and 2)to evaluate the costs associated with the disease. This article reports the results of the cost analysis. METHODS: We estimated the cost of treating CTCL over a period of 1year from the perspective of the Spanish National Health System. Twenty-three dermatologists and hematologists from 15 public hospitals analyzed data for adult patients with mycosis fungoides (MF) or Sézary syndrome (SS). RESULTS: A total of 141 patients (57.4% male) with a mean age of 63.6 years (95%CI: 61.4-65.7 years) were included. The mean direct annual cost of treating CTCL was €34,214 per patient. The corresponding costs by stage were €11,952.47 for stageI disease, €23,506.21 for stageII disease, €38,771.81 for stageIII disease, and €72,748.84 for stageIV disease. The total direct annual cost of treating MF/SS in public hospitals in Spain was estimated at €78,301,171; stageI disease accounted for 81% of all costs, stageII for 7%, and stagesIII andIV for 6% each. CONCLUSIONS: The MICADOS study offers an accurate picture of the direct cost of treating CTCL in patients with MF/SS in Spain and shows that costs vary significantly according to disease stage. Patient-borne and indirect costs should be analyzed in future studies.


Assuntos
Linfoma Cutâneo de Células T , Micose Fungoide , Síndrome de Sézary , Neoplasias Cutâneas , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Qualidade de Vida , Espanha/epidemiologia , Neoplasias Cutâneas/terapia , Neoplasias Cutâneas/patologia , Linfoma Cutâneo de Células T/terapia , Linfoma Cutâneo de Células T/patologia , Micose Fungoide/terapia , Micose Fungoide/patologia , Síndrome de Sézary/terapia , Síndrome de Sézary/patologia
3.
Actas Dermosifiliogr ; 115(6): 547-554, 2024 Jun.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-38395224

RESUMO

BACKGROUND AND OBJECTIVES: Bexarotene has been approved to treat advanced stage cutaneous T-cell lymphomas (CTCL) since 1999. However, very few data have been published on its long-term safety and efficacy profile. The aim of this study is to determine the tolerability to bexarotene and outcomes by collecting the 2nd largest case series to date on its long-term use vs CTCL. MATERIAL AND METHOD: This was a multicenter retrospective review of 216 patients with mycosis fungoides (174), or Sézary syndrome (42) on a 10-year course of bexarotene alone or in combination with other therapies at 19 tertiary referral teaching hospitals. RESULTS: A total of 133 men (62%) and 83 women (38%) were included, with a mean age of 63.5 year (27-95). A total of 45% were on bexarotene monotherapy for the entire study period, 22% started on bexarotene but eventually received an additional therapy, 13% were on another treatment but eventually received bexarotene while the remaining 20% received a combination therapy since the beginning. The median course of treatment was 20.78 months (1-114); and the overall response rate, 70.3%. Complete and partial response rates were achieved in 26% and 45% of the patients, respectively. Treatment was well tolerated, being the most common toxicities hypertriglyceridemia (79%), hypercholesterolemia (71%), and hypothyroidism (52%). No treatment-related grade 5 adverse events were reported. CONCLUSIONS: Our study confirms bexarotene is a safe and effective therapy for the long-term treatment of CTCL.


Assuntos
Bexaroteno , Micose Fungoide , Síndrome de Sézary , Neoplasias Cutâneas , Tetra-Hidronaftalenos , Humanos , Bexaroteno/uso terapêutico , Masculino , Feminino , Idoso , Estudos Retrospectivos , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Neoplasias Cutâneas/tratamento farmacológico , Adulto , Tetra-Hidronaftalenos/uso terapêutico , Tetra-Hidronaftalenos/efeitos adversos , Micose Fungoide/tratamento farmacológico , Síndrome de Sézary/tratamento farmacológico , Espanha , Linfoma Cutâneo de Células T/tratamento farmacológico , Resultado do Tratamento , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos
4.
J Endocrinol Invest ; 44(9): 1837-1846, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33575974

RESUMO

PURPOSE: Medullary thyroid carcinoma (MTC) displays a wide variety of histopathological features, and several histological variants have been described. In follicular cell-derived thyroid carcinomas, there is a good correlation between genotype and phenotype. In this study, we investigated whether such a correlation is also present in MTC. METHODS: The histopathological features were evaluated in a series of 66 molecularly characterised tumours and correlated with the clinical characteristics. RESULTS: Most MTC exhibited the classical variant (83.3%). Other variants included spindle cell (6.1%), pseudopapillary (4.5%), paraganglioma-like (3.0%), angiosarcoma-like (1.5%), and oncocytic follicular (1.5%). Tumours were classified into four groups: group 1, with somatic p.Met918Thr and p.Ala883Phe RET mutations; group 2, with other RET mutations; group 3, with RAS mutations; and group 4, without RET or RAS mutations. Tumours from groups 1 and 4 were typically associated with the classical variant, with abundant fibrosis, lymphovascular invasion, extrathyroidal extension, and more advanced stages of disease, whereas group 2 included histological variants other than the classical variant (namely, pseudopapillary and paraganglioma-like), with tumours that were highly cellular, less invasive, and with a better overall prognosis. In tumours from group 4, amyloid deposition was characteristically absent or low. The spindle cell variant appeared only in tumours from group 3, which had high cellularity and a degree of invasion and prognosis intermediate between groups 1 and 2, but better than group 4. The grade of fibrosis correlated directly with the clinical outcome. CONCLUSION: Our results support the idea that a genotype-phenotype correlation does, indeed, exist in MTC. However, further studies are warranted to confirm these findings in a larger sample size.


Assuntos
Carcinoma Neuroendócrino/genética , Carcinoma Neuroendócrino/patologia , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Amiloide/metabolismo , Carcinoma/metabolismo , Carcinoma/patologia , Feminino , Fibrose , Genes ras/genética , Variação Genética , Humanos , Masculino , Pessoa de Meia-Idade , Mutação/genética , Invasividade Neoplásica , Patologia Molecular , Prognóstico , Proteínas Proto-Oncogênicas c-ret/genética , Estudos Retrospectivos
5.
Exp Parasitol ; 218: 107998, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32941889

RESUMO

The aims of this study were to evaluate the efficacy of two injectable formulations of doramectin (DRM) against Psoroptes ovis in sheep infested under controlled experimental conditions and to characterize the DRM plasma disposition kinetics in the infested animals. To this end, sheep were experimentally infested with a P. ovis strain from a farm with a history of treatment failure, and then treated either with DRM 1% (traditional preparation) on days 0 and 7 or with DRM 3.15% (long-acting formulation) on day 0. The efficacy of each treatment was calculated by counting live mites in skin scrapings. Plasma samples were obtained from each animal and DRM concentrations were measured by HPLC. After the two doses of DRM 1%, the maximum efficacy (98.8%) was reached on day 28, whereas after the single dose of DRM 3.15%, the maximum efficacy (100%) was reached on day 35 and ratified on day 42. The long-acting formulation allowed obtaining higher exposure and more sustained concentrations of DRM than the traditional preparation. Although both DRM formulations studied were effective according to international protocols, they did not reach 100% effectiveness in the time required for approved pharmaceutical products against sheep scab, according to Argentine regulations.


Assuntos
Inseticidas/uso terapêutico , Ivermectina/análogos & derivados , Infestações por Ácaros/veterinária , Psoroptidae/efeitos dos fármacos , Doenças dos Ovinos/tratamento farmacológico , Animais , Disponibilidade Biológica , Feminino , Meia-Vida , Injeções Subcutâneas/veterinária , Inseticidas/administração & dosagem , Inseticidas/sangue , Inseticidas/farmacologia , Ivermectina/administração & dosagem , Ivermectina/sangue , Ivermectina/farmacologia , Ivermectina/uso terapêutico , Masculino , Infestações por Ácaros/tratamento farmacológico , Psoroptidae/crescimento & desenvolvimento , Ovinos , Doenças dos Ovinos/parasitologia
6.
J Neural Transm (Vienna) ; 126(10): 1321-1328, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31377952

RESUMO

Previously, we found out that in ovariectomized female rats, estrogen and progesterone produce a memory deficit which is reverted by the intrahippocampal administration of allopregnanolone. Here, we study the possible interplay between allopregnanolone and hippocampal serotonergic activity. Ovariectomized rats injected subcutaneously with estrogen and progesterone were subsequently injected in the dorsal hippocampus with vehicle, allopregnanolone alone or allopregnanolone shortly after 8OH-DPAT, a predominantly 5HT1A-7 receptor agonist. Then, the subjects were sequentially tested in: (1) an inhibitory avoidance task and (2) K+-evoked [3H]-serotonin ex vivo release through superfusion experiments. Allopregnanolone increased the K+-evoked [3H]-serotonin release compared to control. 8OH-DPAT infusions reversed the effects of allopregnanolone on memory and K+-evoked [3H]-serotonin release. These results suggest that allopregnanolone memory improvement could be mediated, at least in part, through modulation of the hippocampal serotonergic system reactivity.


Assuntos
Estrogênios/farmacologia , Transtornos da Memória/metabolismo , Transtornos da Memória/prevenção & controle , Pregnanolona/uso terapêutico , Progesterona/farmacologia , Serotonina/metabolismo , Animais , Feminino , Locomoção/efeitos dos fármacos , Locomoção/fisiologia , Transtornos da Memória/induzido quimicamente , Ovariectomia/efeitos adversos , Pregnanolona/farmacologia , Ratos , Ratos Sprague-Dawley , Agonistas do Receptor de Serotonina/farmacologia
7.
J Endocrinol Invest ; 42(3): 313-318, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29968046

RESUMO

PURPOSE: The EIF1AX gene was recently described as a new thyroid cancer-related gene. Its mutations were mainly reported in poorly differentiated (PDTC) and anaplastic thyroid cancers (ATC), but also in well-differentiated thyroid cancer (WDTC) and in benign thyroid lesions, although less frequently. Our aim was to address whether EIF1AX mutations are present in the different stages of thyroid tumourigenesis (from hyperplasia to well-differentiated and to poorly differentiated/undifferentiated lesions), and to clarify its role in this process. METHODS: We analysed the EIF1AX gene in a series of 16 PDTC and ATC cases with coexistent well-differentiated regions and/or benign lesions. In EIF1AX mutant cases we also assessed the presence of RAS genes mutations. RESULTS: We identified the mutation p.Ala113_splice in the EIF1AX gene in two PDTCs (neither present in the well-differentiated counterparts nor in the benign areas). One of these tumours also evidenced the mutation p.Glu61Arg in NRAS in both poorly and well-differentiated regions, further suggesting that the EIF1AX p.Ala113_splice mutation could be associated with tumoural progression. In another patient we did not find any EIF1AX alteration in the PDTC component, but we detected the EIF1AX p.Gly6_splice mutation in the PTC area (both regions were RAS wild-type). This mutation did not seem to be related with dedifferentiation. CONCLUSIONS: According to our results, distinct mutations on EIF1AX may be related to different phenotypes/behaviours. Despite being a small series, which reflects the difficulty in retrieving PDTC and ATC surgical samples with well-differentiated and/or benign areas, our study may provide new insights into thyroid cancer tumourigenesis and dedifferentiation.


Assuntos
Adenocarcinoma/patologia , Carcinogênese/patologia , Fator de Iniciação 1 em Eucariotos/genética , Mutação , Regiões Promotoras Genéticas , Neoplasias da Glândula Tireoide/patologia , Adenocarcinoma/genética , Carcinogênese/genética , Progressão da Doença , Feminino , Genes ras , Humanos , Masculino , Prognóstico , Splicing de RNA , Neoplasias da Glândula Tireoide/genética
9.
Biochem Biophys Res Commun ; 500(1): 94-101, 2018 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-28438601

RESUMO

Mitochondrial adaptation to different physiological conditions highly relies on the regulation of mitochondrial ultrastructure, particularly at the level of cristae compartment. Cristae represent the membrane hub where most of the respiratory complexes embed to account for OXPHOS and energy production in the form of adenosine triphosphate (ATP). Changes in cristae number and shape define the respiratory capacity as well as cell viability. The identification of key regulators of cristae morphology and the understanding of their contribution to the mitochondrial ultrastructure and function have become an strategic goal to understand mitochondrial disorders and to exploit as therapeutic targets. This review summarizes the known regulators of cristae ultrastructure and discusses their contribution and implications for mitochondrial dysfunction.


Assuntos
Complexo de Proteínas da Cadeia de Transporte de Elétrons/metabolismo , Células Eucarióticas/metabolismo , Mitocôndrias/metabolismo , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Membranas Mitocondriais/metabolismo , ATPases Mitocondriais Próton-Translocadoras/metabolismo , Trifosfato de Adenosina/biossíntese , Sobrevivência Celular , Complexo de Proteínas da Cadeia de Transporte de Elétrons/genética , Células Eucarióticas/ultraestrutura , GTP Fosfo-Hidrolases/genética , GTP Fosfo-Hidrolases/metabolismo , Regulação da Expressão Gênica , Humanos , Mitocôndrias/ultraestrutura , Proteínas de Transporte da Membrana Mitocondrial/genética , Membranas Mitocondriais/ultraestrutura , ATPases Mitocondriais Próton-Translocadoras/genética , Forma das Organelas/fisiologia , Fosforilação Oxidativa , Multimerização Proteica , Transdução de Sinais
12.
Opt Express ; 25(15): 17004-17020, 2017 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-28789199

RESUMO

We present a class of binary masks that encode, in polar coordinates, the values of a Hadamard matrix of order N. For order N ≥ 2, the binary masks increase the Strehl ratio vs. focus error by the factor N, with the highest possible light throughput. Since a Strehl ratio with high tolerance to defocus does not guarantee a modulation transfer function (MTF) with low sensitivity to focus errors, then, we show that for N = 16 the binary mask reduces also the impact of focus error on the MTF. Equivalently, the discrete binary mask has Fisher information with low variations to defocus.

13.
Epidemiol Infect ; 144(10): 2230-40, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26899531

RESUMO

Boiling is the most common method of household water treatment in developing countries; however, it is not always effectively practised. We conducted a randomized controlled trial among 210 households to assess the effectiveness of water pasteurization and safe-storage interventions in reducing Escherichia coli contamination of household drinking water in a water-boiling population in rural Peru. Households were randomized to receive either a safe-storage container or a safe-storage container plus water pasteurization indicator or to a control group. During a 13-week follow-up period, households that received a safe-storage container and water pasteurization indicator did not have a significantly different prevalence of stored drinking-water contamination relative to the control group [prevalence ratio (PR) 1·18, 95% confidence interval (CI) 0·92-1·52]. Similarly, receipt of a safe-storage container alone had no effect on prevalence of contamination (PR 1·02, 95% CI 0·79-1·31). Although use of water pasteurization indicators and locally available storage containers did not increase the safety of household drinking water in this study, future research could illuminate factors that facilitate the effective use of these interventions to improve water quality and reduce the risk of waterborne disease in populations that boil drinking water.


Assuntos
Água Potável/microbiologia , Infecções por Escherichia coli/prevenção & controle , Pasteurização/métodos , Purificação da Água/métodos , Qualidade da Água , Escherichia coli/fisiologia , Características da Família , Humanos , Peru , População Rural
14.
Surg Radiol Anat ; 38(9): 1033-1043, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26983817

RESUMO

PURPOSE: The discrepancies in the literature regarding the anatomy of the temporomandibular joint (TMJ), particularly at the level of the lateral pterygoid muscle, led us to compare plastinated section techniques and magnetic resonance imaging (MRI) to enable the better interpretation of both, and to describe the features of the lateral pterygoid muscle and the exact location of its insertions. METHODS: A total of 24 blocks of human TMJ were used. Seven were studied by MRI, obtaining images of the oblique-sagittal, oblique-coronal, and axial planes. Four of these blocks were then cut and processed by means of the E12 plastination technique. The remaining blocks were dissected. Finally, we performed a comparative morphological analysis of the different techniques used. RESULTS: New aspects about the morphology and the insertions of the lateral pterygoid muscle are described. The muscle is inserted into the disc, capsule, condyle, and the pterygoid fovea, through muscle and tendon fibres that alternate, giving it the characteristic of a multipennate muscle. This insertion caudally exceeded the pterygoid fovea and descends to near the lingula of mandible. A profuse pterygoid venous plexus surrounds the whole joint complex, and also the insertion zone of the lateral pterygoid muscle. CONCLUSIONS: We consider that the use of transparent-plastinated anatomical sections and its good correlation with MRI images (in axial and oblique-sagittal planes) led to an accurate identification of TMJ structures, especially in relation to the lateral pterygoid muscle, that is now described as a multipennate muscle.


Assuntos
Músculos Pterigoides/anatomia & histologia , Músculos Pterigoides/diagnóstico por imagem , Transtornos da Articulação Temporomandibular/diagnóstico por imagem , Idoso , Crioultramicrotomia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino
17.
Eur Arch Otorhinolaryngol ; 272(4): 971-979, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24695942

RESUMO

The objectives of the study were to evaluate the performance of sentinel lymph node biopsy (SLNB) in detecting occult metastases in papillary thyroid carcinoma (PTC) and to correlate their presence to tumor and patient characteristics. Twenty-three clinically node-negative PTC patients (21 females, mean age 48.4 years) were prospectively enrolled. Patients were submitted to sentinel lymph node (SLN) lymphoscintigraphy prior to total thyroidectomy. Ultrasound-guided peritumoral injections of (99m)Tc-phytate (7.4 MBq) were performed. Cervical single-photon emission computed tomography and computed tomography (SPECT/CT) images were acquired 15 min after radiotracer injection and 2 h prior to surgery. Intra-operatively, SLNs were located with a gamma probe and removed along with non-SLNs located in the same neck compartment. Papillary thyroid carcinoma, SLNs and non-SLNs were submitted to histopathology analysis. Sentinel lymph nodes were located in levels: II in 34.7 % of patients; III in 26 %; IV in 30.4 %; V in 4.3 %; VI in 82.6 % and VII in 4.3 %. Metastases in the SLN were noted in seven patients (30.4 %), in non-SLN in three patients (13.1 %), and in the lateral compartments in 20 % of patients. There were significant associations between lymph node (LN) metastases and the presence of angio-lymphatic invasion (p = 0.04), extra-thyroid extension (p = 0.03) and tumor size (p = 0.003). No correlations were noted among LN metastases and patient age, gender, stimulated thyroglobulin levels, positive surgical margins, aggressive histology and multifocal lesions. Sentinel lymph node biopsy can detect occult metastases in PTC. The risk of a metastatic SLN was associated with extra-thyroid extension, larger tumors and angio-lymphatic invasion. This may help guide future neck dissection, patient surveillance and radioiodine therapy doses.


Assuntos
Carcinoma/diagnóstico , Carcinoma/secundário , Linfonodos/patologia , Biópsia de Linfonodo Sentinela/métodos , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/secundário , Carcinoma/cirurgia , Carcinoma Papilar , Feminino , Humanos , Linfonodos/cirurgia , Metástase Linfática , Linfocintigrafia , Masculino , Pessoa de Meia-Idade , Esvaziamento Cervical , Estadiamento de Neoplasias , Estudos Prospectivos , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada por Raios X
18.
Microbiology (Reading) ; 160(Pt 12): 2780-2793, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25246670

RESUMO

In Escherichia coli, the oxidative branch of the pentose phosphate pathway (oxPPP) is one of the major sources of NADPH when glucose is the sole carbon nutrient. However, unbalanced NADPH production causes growth impairment as observed in a strain lacking phosphoglucoisomerase (Δpgi). In this work, we studied the metabolic response of this bacterium to the replacement of its glucose-6-phosphate dehydrogenase (G6PDH) by an NADH-producing variant. The homologous enzyme from Leuconostoc mesenteroides was studied by molecular dynamics and site-directed mutagenesis to obtain the NAD-preferring LmG6PDH(R46E,Q47E). Through homologous recombination, the zwf loci (encoding G6PDH) in the chromosomes of WT and Δpgi E. coli strains were replaced by DNA encoding LmG6PDH(R46E,Q47E). Contrary to some predictions performed with flux balance analysis, the replacements caused a substantial effect on the growth rates, increasing 59 % in the Δpgi strain, while falling 44 % in the WT. Quantitative PCR (qPCR) analysis of the zwf locus showed that the expression level of the mutant enzyme was similar to the native enzyme and the expression of genes encoding key enzymes of the central pathways also showed moderate changes among the studied strains. The phenotypic and qPCR data were integrated into in silico modelling, showing an operative G6PDH flux contributing to the NADH pool. Our results indicated that, in vivo, the generation of NADH by G6PDH is beneficial or disadvantageous for growth depending on the operation of the upper Embden-Meyerhof pathway. Interestingly, a genomic database search suggested that in bacteria lacking phosphofructokinase, the G6PDHs tend to have similar preferences for NAD and NADP. The importance of the generation of NADPH in a pathway such as the oxPPP is discussed.


Assuntos
Escherichia coli/enzimologia , Escherichia coli/metabolismo , Glucosefosfato Desidrogenase/metabolismo , NAD/metabolismo , Simulação por Computador , Escherichia coli/crescimento & desenvolvimento , Deleção de Genes , Perfilação da Expressão Gênica , Glucosefosfato Desidrogenase/genética , Leuconostoc/enzimologia , Leuconostoc/genética , Engenharia Metabólica , Análise do Fluxo Metabólico , Redes e Vias Metabólicas/genética , Reação em Cadeia da Polimerase em Tempo Real , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Recombinação Genética , Biologia de Sistemas
19.
Am J Bot ; 101(2): 357-64, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24458119

RESUMO

PREMISE OF STUDY: Floral thermogenesis is an unusual floral trait with a well-documented physiological process, and yet, there is limited understanding of how this trait influences plant reproduction. The current study was undertaken to gain a better understanding of how floral thermogenesis in Nelumbo lutea impacts pollinator attraction and consequent plant reproduction. METHODS: We conducted field studies on floral thermogenesis and thermoregulation, flower sexual development, floral visitation patterns, breeding system, pollen transfer dynamics, and floral scent production. KEY RESULTS: The most abundant visitors to the thermoregulatory flowers included the Phoridae (Diptera), Chrysomelidae (Coleoptera), and Hymenoptera. Chrysomelid beetles, particularly Diabrotica, were frequent visitors to both first-day female- and second-day bisexual-phase flowers, while phorid flies were most common in bisexual-phase flowers. Pollen transfer experiments indicated that Diabrotica was equally effective in depositing pollen on stigmas, as were the less frequent, but pollen-loaded halictid bees. CONCLUSIONS: Flowers received a taxonomically wide assemblage of floral visitors and appear adapted to attract beetles, primarily Chrysomelidae and medium-sized bees. This study is the first to provide strong support that beetles can comprise the dominant portion of floral visitors and are as effective in pollen transfer as bees. Thermogenesis aids in dispersing the main floral scent component-1,4-dimethoxybenzene-attracting both chrysomelids and bees, while thermoregulation causes chrysomelid beetles to actively seek out new flowers for evening residence. This search behavior likely results in chrysomelids affecting cross-pollination.


Assuntos
Besouros , Dípteros , Flores/fisiologia , Himenópteros , Nelumbo/fisiologia , Polinização , Termogênese , Adaptação Biológica , Animais , Anisóis/metabolismo , Ecologia , Flores/metabolismo , Odorantes , Pólen , Reprodução
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