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1.
J Insect Sci ; 19(2)2019 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-31222324

RESUMEN

Developments in understanding bee responses to habitat loss indicate that body size is a trait with important consequences for conservation. Stingless bees (Hymenoptera, Apidae, Meliponini) are a diverse group of eusocial bees providing pollination services in tropical landscapes, exhibiting a large range in body size across species. We tested the effects of deforestation on the body sizes of stingless bee communities by using museum specimens and revisiting a previous effort that sampled stingless bee communities across varying levels of deforestation at 183 sites in Rondônia, Brazil, in 1996-1997. Body size measurements (intertegular distance) from 72 species collected were included as dependent variables in response to forest area, forest edge, and connectivity of forest patches at several spatial scales. We find that stingless bee body size is negatively related to forest cover: mean community body size was larger in areas with greater amounts of deforestation, and smaller in areas with less deforestation. Second, stingless bee species richness was positively associated with forest edge regardless of body size. Lastly, we find that as forest patch isolation increased, the stingless bee community body size also increased. These findings support hypotheses that small stingless bee species might be more negatively affected by deforestation, adding to the growing body of evidence that stingless bees require areas of intact forest in near proximity to other forest patches to conserve these diverse pollinator communities.


Asunto(s)
Abejas , Tamaño Corporal , Conservación de los Recursos Naturales , Ecosistema , Animales , Brasil
2.
Genet Mol Res ; 15(4)2016 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-27966747

RESUMEN

To elucidate the resistance of high-yield hybrid rice (Oryza sativa L.) at the seedling stage to low temperature, photosynthetic characteristics, such as membrane lipid peroxidation, fatty acid composition, and chloroplast ultrastructure, were investigated in a newly developed super-hybrid rice ('Liangyoupeijiu') and a traditional chill-sensitive hybrid rice ('Shanyou63'), with 20°C as the control condition and 10°C as the low temperature treatment. Chlorophyll content, oxygen consumption by photosystem I, and oxygen production by photosystem II in the thylakoid membrane mainly decreased under the low-temperature treatment. The malondialdehyde content of 'Liangyoupeijiu' decreased slightly, while increases in membrane lipid peroxidation were greater in 10°C-treated than in 25°C-treated 'Shanyou63' seedlings. The index of unsaturated fatty acids increased in the two cultivars, particularly in 'Liangyoupeijiu'. No severe chloroplast ultrastructure damage was observed under cold stress, but the number of osmiophilic granules in 'Shanyou63' increased rapidly. The results indicate that compared to 'Shanyou63', 'Liangyoupeijiu' is more chill-resistant at the seedling stage.


Asunto(s)
Oryza/fisiología , Fotosíntesis , Plantones/crecimiento & desarrollo , Quimera , Cloroplastos/ultraestructura , Frío , Ácidos Grasos/análisis , Peroxidación de Lípido , Oryza/ultraestructura , Estrés Fisiológico
3.
Genet Mol Res ; 15(3)2016 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-27706684

RESUMEN

Buffalo are characteristic livestock of the Guangxi Zhuang Autonomous Region of China, but their low reproductive capacity necessitates the use of somatic cell nuclear transfer (SCNT). We investigated the effects of RG108 on DNA methylation in buffalo adult fibroblasts, and on subsequent SCNT embryo development. RG108 treatment (0, 5, 10, 20, and 100 mM) had no effect on cell morphology, viability, or karyotype (2n = 48), and cell growth followed a typical "S" curve. Immunohistochemistry showed that relative DNA methylation gradually decreased as RG108 concentration increased, and was significantly lower in the 20 and 100 mM groups compared to the 0, 5, and 10 mM treatments (0.94 ± 0.03 and 0.92 ± 0.05 vs 1.0 ± 0.02, 0.98 ± 0.05, and 0.98 ± 0.09, respectively; P < 0.05). Quantitative polymerase chain reaction revealed that DNMT1 gene expression of fibroblasts administered 10, 20, and 100 mM RG108 was significantly lower than those in the 0 and 5 mM groups (0.2 ± 0.05, 0.18 ± 0.07, and 0.3 ± 0.09 vs 1.0 ± 0.12 and 1.4 ± 0.12, respectively; P < 0.05). Treatment with 20 mM RG108 resulted in the lowest expression levels. Fibroblasts incubated with 20 mM RG108 for 72 h were used as donor cells to generate SCNT embryos. A greater number of such embryos developed into blastocysts compared to the non-treated group (28.9 ± 3.9 vs 15.3 ± 3.4%; P < 0.05). RG108 treatment can modify DNA methylation in buffalo adult fibroblasts and promote development of subsequent SCNT embryos.


Asunto(s)
Búfalos/genética , ADN (Citosina-5-)-Metiltransferasas/antagonistas & inhibidores , Inhibidores Enzimáticos/farmacología , Epigénesis Genética , Fibroblastos/efectos de los fármacos , Técnicas de Transferencia Nuclear , Ftalimidas/farmacología , Triptófano/análogos & derivados , Animales , Blastocisto/citología , Blastocisto/enzimología , Cruzamiento , Búfalos/metabolismo , ADN (Citosina-5-)-Metiltransferasas/genética , ADN (Citosina-5-)-Metiltransferasas/metabolismo , Metilación de ADN/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Desarrollo Embrionario , Femenino , Fertilización In Vitro , Fibroblastos/citología , Fibroblastos/enzimología , Masculino , Oocitos/citología , Oocitos/metabolismo , Embarazo , Espermatozoides/citología , Espermatozoides/metabolismo , Triptófano/farmacología
4.
Braz J Med Biol Res ; 49(2): e5080, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26871968

RESUMEN

We aimed to evaluate the effectiveness and safety of bismuth-containing quadruple therapy plus postural change after dosing for Helicobacter pylori eradication in gastrectomized patients. We compared 76 gastric stump patients with H. pylori infection (GS group) with 50 non-gastrectomized H. pylori-positive patients who met the treatment indication (controls). The GS group was divided into GS group 1 and GS group 2. All groups were administered bismuth potassium citrate (220 mg), esomeprazole (20 mg), amoxicillin (1.0 g), and furazolidone (100 mg) twice daily for 14 days. GS group 1 maintained a left lateral horizontal position for 30 min after dosing. H. pylori was detected using rapid urease testing and histologic examination of gastric mucosa before and 3 months after therapy. Mucosal histologic manifestations were evaluated using visual analog scales of the updated Sydney System. GS group 1 had a higher prevalence of eradication than the GS group 2 (intention-to-treat [ITT]: P=0.025; per-protocol [PP]: P=0.030), and the control group had a similar prevalence. GS group 2 had a lower prevalence of eradication than controls (ITT: P=0.006; PP: P=0.626). Scores for chronic inflammation and activity declined significantly (P<0.001) 3 months after treatment, whereas those for atrophy and intestinal metaplasia showed no significant change. Prevalence of adverse reactions was similar among groups during therapy (P=0.939). A bismuth-containing quadruple therapy regimen plus postural change after dosing appears to be a relatively safe, effective, economical, and practical method for H. pylori eradication in gastrectomized patients.


Asunto(s)
Antibacterianos/uso terapéutico , Gastrectomía , Muñón Gástrico , Infecciones por Helicobacter/terapia , Helicobacter pylori/efectos de los fármacos , Adulto , Anciano , Anciano de 80 o más Años , Amoxicilina/uso terapéutico , Antiulcerosos/uso terapéutico , Quimioterapia Combinada/métodos , Esomeprazol/uso terapéutico , Femenino , Furazolidona/uso terapéutico , Humanos , Masculino , Metaplasia , Persona de Mediana Edad , Compuestos Organometálicos/uso terapéutico , Posicionamiento del Paciente/estadística & datos numéricos , Citrato de Potasio/uso terapéutico , Resultado del Tratamiento , Adulto Joven
5.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;49(2): e5080, 2016. tab, graf
Artículo en Inglés | LILACS | ID: biblio-951656

RESUMEN

We aimed to evaluate the effectiveness and safety of bismuth-containing quadruple therapy plus postural change after dosing for Helicobacter pylori eradication in gastrectomized patients. We compared 76 gastric stump patients with H. pylori infection (GS group) with 50 non-gastrectomized H. pylori-positive patients who met the treatment indication (controls). The GS group was divided into GS group 1 and GS group 2. All groups were administered bismuth potassium citrate (220 mg), esomeprazole (20 mg), amoxicillin (1.0 g), and furazolidone (100 mg) twice daily for 14 days. GS group 1 maintained a left lateral horizontal position for 30 min after dosing. H. pylori was detected using rapid urease testing and histologic examination of gastric mucosa before and 3 months after therapy. Mucosal histologic manifestations were evaluated using visual analog scales of the updated Sydney System. GS group 1 had a higher prevalence of eradication than the GS group 2 (intention-to-treat [ITT]: P=0.025; per-protocol [PP]: P=0.030), and the control group had a similar prevalence. GS group 2 had a lower prevalence of eradication than controls (ITT: P=0.006; PP: P=0.626). Scores for chronic inflammation and activity declined significantly (P<0.001) 3 months after treatment, whereas those for atrophy and intestinal metaplasia showed no significant change. Prevalence of adverse reactions was similar among groups during therapy (P=0.939). A bismuth-containing quadruple therapy regimen plus postural change after dosing appears to be a relatively safe, effective, economical, and practical method for H. pylori eradication in gastrectomized patients.


Asunto(s)
Humanos , Masculino , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Adulto Joven , Helicobacter pylori/efectos de los fármacos , Infecciones por Helicobacter/terapia , Muñón Gástrico , Gastrectomía , Antibacterianos/uso terapéutico , Compuestos Organometálicos/uso terapéutico , Resultado del Tratamiento , Citrato de Potasio/uso terapéutico , Quimioterapia Combinada/métodos , Posicionamiento del Paciente/estadística & datos numéricos , Esomeprazol/uso terapéutico , Furazolidona/uso terapéutico , Amoxicilina/uso terapéutico , Metaplasia , Antiulcerosos/uso terapéutico
6.
Clin Transl Oncol ; 17(9): 720-6, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26033426

RESUMEN

INTRODUCTION: This study is to evaluate the association of polymorphisms of glutathione S-transferase P1 (GSTP1), copper-transporting P-type adenosine triphosphatase A (ATP7A) and X-ray repair cross-complementing group 1 (XRCC1) with the efficacy and toxicity of cisplatin-based treatment in advanced non-small cell lung cancer (NSCLC) patients. MATERIALS AND METHODS: The outcomes of 97 advanced non-small cell lung cancer patients treated with cisplatin-based chemotherapy were estimated. GSTP1, ATP7A, and XRCC1 genetic polymorphisms were determined via polymerase chain reaction of restriction fragment length polymorphism (PCR-RFLP) and DNA sequencing. Association of the polymorphisms with the efficacy and toxicity of cisplatin was analyzed, respectively. RESULTS: Significant associations were observed between GSTP1 A313G and response rate (RR) (p = 0.027), disease control rate (DCR) (p = 0.019), and progression-free survival (PFS) (p = 0.044), respectively. Patients with AG and GG of GSTP1 have notably lower risk of anemia (p = 0.046). XRCC1 A1196G was associated with the incidence of lymphopenia (p = 0.024) and diarrhea (p = 0.020). ATP7A C2299G was not related with RR, DCR, PFS, and the risk of toxicity. CONCLUSIONS: Advanced NSCLC patients with AA genotype of GSTP1 would obtain better curative effect followed with more risk of anemia when treated by cisplatin-based chemotherapy. ATP7A C2299G does not impact the efficacy and toxicity of cisplatin-based chemotherapy. XRCC1 1196A allele could predict the incidence of lymphopenia and diarrhea.


Asunto(s)
Adenocarcinoma/genética , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Células Escamosas/genética , Proteínas de Unión al ADN/genética , Gutatión-S-Transferasa pi/genética , Neoplasias Pulmonares/genética , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/mortalidad , Adenocarcinoma/patología , Adenosina Trifosfatasas/genética , Adulto , Anciano , Biomarcadores de Tumor/genética , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/mortalidad , Carcinoma de Células Escamosas/patología , Proteínas de Transporte de Catión/genética , Cisplatino/administración & dosificación , ATPasas Transportadoras de Cobre , Desoxicitidina/administración & dosificación , Desoxicitidina/análogos & derivados , Docetaxel , Femenino , Estudios de Seguimiento , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Paclitaxel/administración & dosificación , Pronóstico , Tasa de Supervivencia , Taxoides/administración & dosificación , Vinblastina/administración & dosificación , Vinblastina/análogos & derivados , Vinorelbina , Proteína 1 de Reparación por Escisión del Grupo de Complementación Cruzada de las Lesiones por Rayos X , Gemcitabina
7.
Genet Mol Res ; 11(3): 3490-6, 2012 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-23079842

RESUMEN

The functional polymorphism Ser326Cys (rs1052133) in the human 8-oxoguanine DNA glycosylase (hOGG1) gene has been implicated in bladder cancer risk. However, reports of this association between the Ser326Cys polymorphism and bladder cancer risk are conflicting. In order to help clarify this relationship, we made a meta-analysis of seven case-control studies, summing 2521 cases and 2408 controls. We used odds ratios (ORs) with 95% confidence intervals (95%CIs) to assess the strength of the association. Overall, no significant association between the hOGG1 Ser326Cys polymorphism and bladder cancer risk was found for Cys/Cys vs Ser/Ser (OR = 1.10, 95%CI = 0.74-1.65), Ser/Cys vs Ser/Ser (OR = 1.07, 95%CI = 0.81-1.42), Cys/Cys + Ser/Cys vs Ser/Ser (OR = 1.08, 95%CI = 0.87-1.33), and Cys/Cys vs Ser/Cys + Ser/Ser (OR = 1.04, 95%CI = 0.65-1.69). Even when stratified by ethnicity, no significant association was observed. We concluded that the hOGG1 Ser326Cys polymorphism does not contribute to susceptibility to bladder cancer.


Asunto(s)
Sustitución de Aminoácidos/genética , ADN Glicosilasas/genética , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Polimorfismo de Nucleótido Simple/genética , Neoplasias de la Vejiga Urinaria/genética , Humanos , Sesgo de Publicación , Factores de Riesgo
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