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1.
PLoS One ; 11(1): e0146515, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26742106

RESUMO

Many efforts have been made to develop a rapid and sensitive method for phytoplasma and virus detection. Taking our cue from previous works, different rapid sample preparation methods have been tested and applied to Candidatus Phytoplasma prunorum ('Ca. P. prunorum') detection by RT-qPCR. A duplex RT-qPCR has been optimized using the crude sap as a template to simultaneously amplify a fragment of 16S rRNA of the pathogen and 18S rRNA of the host plant. The specific plant 18S rRNA internal control allows comparison and relative quantification of samples. A comparison between DNA and RNA contribution to qPCR detection is provided, showing higher contribution of the latter. The method presented here has been validated on more than a hundred samples of apricot, plum and peach trees. Since 2013, this method has been successfully applied to monitor 'Ca. P. prunorum' infections in field and nursery. A triplex RT-qPCR assay has also been optimized to simultaneously detect 'Ca. P. prunorum' and Plum pox virus (PPV) in Prunus.


Assuntos
Phytoplasma/genética , Doenças das Plantas/microbiologia , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Prunus/microbiologia , RNA Bacteriano/genética , RNA Bacteriano/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa
2.
Mol Plant Pathol ; 14(4): 422-8, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23384276

RESUMO

Agroinoculation is a quick and easy method for the infection of plants with viruses. This method involves the infiltration of tissue with a suspension of Agrobacterium tumefaciens carrying binary plasmids harbouring full-length cDNA copies of viral genome components. When transferred into host cells, transcription of the cDNA produces RNA copies of the viral genome that initiate infection. We produced full-length cDNA corresponding to Beet necrotic yellow vein virus (BNYVV) RNAs and derived replicon vectors expressing viral and fluorescent proteins in pJL89 binary plasmid under the control of the Cauliflower mosaic virus 35S promoter. We infected Nicotiana benthamiana and Beta macrocarpa plants with BNYVV by leaf agroinfiltration of combinations of agrobacteria carrying full-length cDNA clones of BNYVV RNAs. We validated the ability of agroclones to reproduce a complete viral cycle, from replication to cell-to-cell and systemic movement and, finally, plant-to-plant transmission by its plasmodiophorid vector. We also showed successful root agroinfection of B. vulgaris, a new tool for the assay of resistance to rhizomania, the sugar beet disease caused by BNYVV.


Assuntos
Agrobacterium tumefaciens/metabolismo , DNA Complementar/genética , Técnicas Genéticas , Nicotiana/parasitologia , Nicotiana/virologia , Doenças das Plantas/virologia , Vírus de Plantas/genética , Animais , Northern Blotting , Western Blotting , Genes Reporter , Doenças das Plantas/parasitologia , Folhas de Planta/parasitologia , Folhas de Planta/virologia , Plasmodioforídeos/fisiologia
3.
Virology ; 423(2): 187-94, 2012 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-22209119

RESUMO

Beet soil-borne mosaic virus (BSBMV), like Beet necrotic yellow vein virus (BNYVV), is a member of the Benyvirus genus and both are transmitted by Polymyxa betae. Both viruses possess a similar genomic organization: RNA-1 and -2 are essential for infection and replication while RNA-3 and -4 play important roles in disease development and vector-mediated infection in sugar beet roots. We characterized a new species of BSBMV RNA-4 that encodes a 32 kDa protein and a chimeric form of BSBMV RNA-3 and -4. We demonstrated that BSBMV RNA-4 can be amplified by BNYVV RNA-1 and -2 in planta, is involved in symptoms expression on Chenopodium quinoa plants and can also complement BNYVV RNA-4 for virus transmission through its vector P. betae in Beta vulgaris plants. Using replicon-mediated expression, we demonstrate for the first time that a correct expression of RNAs-4 encoded proteins is essential for benyvirus transmission.


Assuntos
Beta vulgaris/virologia , Vírus do Mosaico/genética , Doenças das Plantas/virologia , Plasmodioforídeos/virologia , Vírus de RNA/genética , Proteínas Virais/metabolismo , Vírus do Mosaico/metabolismo , Vírus de RNA/metabolismo , Microbiologia do Solo , Proteínas Virais/genética
4.
Womens Health (Lond) ; 6(4): 577-93, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20597621

RESUMO

Metformin is quite an old drug, but it is optimal for the control of glycemia in Type 2 diabetes. It was reported, 15 years ago, that insulin resistance was abnormally high in most polycystic ovary syndrome (PCOS) patients. Starting from that moment, increasing numbers of studies were performed to demonstrate the efficacy of metformin in controlling and/or modulating several aspects of PCOS, which is the most common cause of menstrual irregularity, inesthetisms and infertility. Metformin induces higher glucose uptake, thus inducing a lower synthesis/secretion of insulin. Such an effect permits the possible restoration of the normal biological functions that are severely affected by the compensatory hyperinsulinemia reactive to the increased peripheral insulin resistance. These are the basis of the many positive effects of this drug, such as the restoration of menstrual cyclicity, ovulatory cycles and fertility, because abnormal insulin levels affect the hypothalamus-pituitary-ovarian function, as well as the use of glucose in peripheral tissues. Metformin improves the impairments typically observed in hyperinsulinemic PCOS patients, reducing the possible evolution towards metabolic syndrome and Type 2 diabetes; and when pregnancy occurs, it consistently reduces the risk of gestational diabetes, eclampsia and hypertension. PCOS seems to be the perfect physiopathological condition that might have higher benefits from metformin administration, obviously after Type 2 diabetes. This review focuses on the many aspects of PCOS and on the possible issues of this disease for which metformin might be a putative optimal treatment.


Assuntos
Hipoglicemiantes/uso terapêutico , Metformina/uso terapêutico , Síndrome do Ovário Policístico/tratamento farmacológico , Adaptação Psicológica , Índice de Massa Corporal , Sistema Endócrino/patologia , Feminino , Humanos , Hiperandrogenismo/patologia , Hipoglicemiantes/efeitos adversos , Hipoglicemiantes/farmacocinética , Resistência à Insulina , Distúrbios Menstruais/patologia , Metformina/efeitos adversos , Metformina/farmacocinética , Síndrome do Ovário Policístico/patologia , Síndrome do Ovário Policístico/psicologia , Gravidez , Qualidade de Vida
5.
Gynecol Endocrinol ; 24(3): 139-44, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18335328

RESUMO

OBJECTIVE: To evaluate the effects the administration of myo-inositol (MYO) on hormonal parameters in a group of PCOS patients. DESIGN: Controlled clinical study. SETTING: PCOS patients in a clinical research environment. PATIENTS: 20 overweight PCOS patients were enrolled after informed consent. INTERVENTIONS: All patients underwent hormonal evaluations and an oral glucose tollerance test (OGTT) before and after 12 weeks of therapy (Group A (n = 10): myo-inositol 2 gr. plus folic acid 200 mug every day; Group B (n = 10): folic acid 200 mug every day). Ultrasound examinations and Ferriman-Gallwey score were also performed. MAIN OUTCOME MEASURES: Plasma LH, FSH, PRL, E2, 17OHP, A, T, glucose, insulin, C peptide concentrations, BMI, HOMA index and glucose-to-insulin ratio. RESULTS: After 12 weeks of MYO administration plasma LH, PRL, T, insulin levels and LH/FSH resulted significantly reduced. Insulin sensitivity, expressed as glucose-to-insulin ratio and HOMA index resulted significantly improved after 12 weeks of treatment. Menstrual cyclicity was restored in all amenorrheic and oligomenorrheic subjects. No changes occurred in the patients treated with folic acid. CONCLUSIONS: Myo-inositol administration improves reproductive axis functioning in PCOS patients reducing the hyperinsulinemic state that affects LH secretion.


Assuntos
Hormônios/sangue , Hiperinsulinismo/tratamento farmacológico , Inositol/administração & dosagem , Síndrome do Ovário Policístico/tratamento farmacológico , Glicemia/análise , Índice de Massa Corporal , Peso Corporal , Estradiol/sangue , Feminino , Ácido Fólico/administração & dosagem , Hormônio Foliculoestimulante/sangue , Teste de Tolerância a Glucose , Humanos , Insulina/sangue , Hormônio Luteinizante/sangue , Síndrome do Ovário Policístico/sangue , Síndrome do Ovário Policístico/diagnóstico por imagem , Prolactina/sangue , Testosterona/sangue , Ultrassonografia
6.
Gynecol Endocrinol ; 23(3): 146-52, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17454168

RESUMO

BACKGROUND: Polycystic ovary syndrome (PCOS) is a common endocrine disease that is frequently observed to be related to increased insulin resistance independent of body weight. The use of insulin-sensitizer compounds, such as metformin, permits great improvement of such metabolic abnormality, restoring ovarian function and gonadal steroid synthesis and reducing insulin resistance. AIM: On this basis we aimed to evaluate a group of non-obese amenorrheic PCOS patients before and after 6 months of metformin administration (500 mg orally twice daily) to better understand upon which basis of clinical and endocrine parameters metformin administration might be chosen as a putative therapeutic tool. METHOD: A group of non-obese PCOS patients (n = 42) was enrolled after informed consent. They underwent an oral glucose tolerance test for insulin, glucose and C-peptide levels and provided blood samples for determination of plasma levels of luteinizing hormone (LH), follicle-stimulating hormone, prolactin, estradiol, androstenedione, 17-hydroxyprogesterone, insulin, cortisol and testosterone levels on two occasions: before and on day 7 of the first menstrual cycle occurring after the 5th month of treatment. RESULTS: Plasma LH, estradiol, insulin and C-peptide were decreased significantly by metformin treatment in the entire group of PCOS patients. When subdividing PCOS patients according to insulin sensitivity (i.e. hyper- and normoinsulinemic subjects), a greater rate of positive endocrine changes was observed in hyperinsulinemic patients and the highest rate was observed in hyperinsulinemic hyperandrogenic subjects. Menstrual cyclicity was recovered in all patients under treatment. CONCLUSIONS: Our data show that metformin modulates ovarian function and greatly affects LH secretion through reduction of the hyperandrogenic condition. The highest rate of endocrine changes was observed in the hyperinsulinemic hyperandrogenic non-obese PCOS patients. Our study demonstrates that metformin administration is more appropriate in hyperinsulinemic hyperandrogenic non-obese PCOS patients.


Assuntos
Hiperandrogenismo/tratamento farmacológico , Hiperinsulinismo/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Metformina/uso terapêutico , Síndrome do Ovário Policístico/tratamento farmacológico , Adolescente , Adulto , Amenorreia/tratamento farmacológico , Feminino , Teste de Tolerância a Glucose , Humanos , Oligomenorreia/tratamento farmacológico , Fenóis , Pirimidinas , Índice de Gravidade de Doença , Resultado do Tratamento
7.
Drugs Aging ; 24(3): 173-85, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17362047

RESUMO

Dehydroepiandrosterone (DHEA) [prasterone] is typically secreted by the adrenal glands and its secretory rate changes throughout the human lifespan. When human development is completed and adulthood is reached, DHEA and DHEA sulphate (DHEAS) [PB-008] levels start to decline so that at 70-80 years of age, peak DHEAS concentrations are only 10-20% of those in young adults. This age-associated decrease has been termed 'adrenopause', and since many age-related disturbances have been reported to begin with the decline of DHEA/DHEAS levels, this provides a potential opportunity for use of DHEA as replacement therapy. For these reasons, use of DHEA as a replacement therapy in aging men and women has been proposed and this paper outlines the reported beneficial effects of such treatment in humans. Many interesting results have been obtained in experimental animals suggesting that DHEA positively modulates most age-related disturbances. However, renewed interest in DHEA has arisen as a result of recent studies suggesting that DHEA appears to be beneficial in hypoandrogenic men as well as in postmenopausal and aging women. Menopause is the event in a woman's life that induces a dramatic change in the steroid milieu, and use of DHEA as 'replacement treatment' has been reported to restore both the androgenic and estrogenic environment and reduce most of the symptoms of this change. As menopause is the beginning of the biological transition of women towards senescence, it is of great interest to better understand how DHEA might help to solve and/or overcome the problems of this complex stage of life. In men with adrenal insufficiency and hypogonadism without androgen replacement, DHEA administration results in a significant increase in circulating androgens. Though most data are suggestive for use of DHEA as hormonal replacement treatment, more defined and specific clinical trials are needed to uncover all of the 'secrets' and features of this steroid before it can be used as a standard treatment. Furthermore, DHEA is perceived differently around the world, being considered only a 'dietary supplement' in the US, while in many European countries it is considered a 'true hormone' that has not been approved for use as a hormonal treatment by the European health authorities. This overview offers some points of view on use of DHEA as an experimental hormonal replacement therapy.


Assuntos
Idoso/fisiologia , Desidroepiandrosterona/uso terapêutico , Terapia de Reposição Hormonal , Idoso de 80 Anos ou mais , Desidroepiandrosterona/metabolismo , Desidroepiandrosterona/fisiologia , Feminino , Humanos , Masculino
8.
Gynecol Endocrinol ; 22(1): 36-43, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16522532

RESUMO

BACKGROUND: Polycystic ovary syndrome (PCOS) is a common endocrine disease that is observed frequently to be related to increased insulin resistance. The use of insulin-sensitizer compounds, such as metformin, permits great improvement of such metabolic abnormality and the restoration of normal ovarian function. Metformin administration reduces insulin resistance and androgen production both from the ovary and adrenal gland. AIM: On this basis we aimed to evaluate a group of non-obese amenorrheic PCOS patients before and after 6 months of metformin administration (500 mg per os twice daily) to better understand what changes might be induced by metformin on adrenal and ovarian function and in terms of temporal coupling of the pulsatile profiles of luteinizing hormone (LH), cortisol and allopregnanolone, the latter representative of the neurosteroid family. METHOD: A group of non-obese PCOS patients (n = 8) was enrolled after informed consent and underwent to a pulsatility study for LH, cortisol and allopregnanolone, and an oral glucose tolerance test before and on day 7 of the first menstrual cycle occurring after the 5th month of treatment. RESULTS: Plasma androgen levels were decreased significantly by metformin treatment, as were plasma LH and allopregnanolone levels and insulin resistance. Metformin administration decreased LH pulse amplitude but not pulse frequency. On the contrary, cortisol and allopregnanolone showed a significant change in pulse frequency. When temporal coupling was tested between pulsatile profiles of LH or cortisol with allopregnanolone, cortisol pulses were temporally coupled to allopreganolone peaks both before and under metformin administration while LH pulses were temporally coupled to allopreganolone secretory peaks only under metformin treatment. CONCLUSIONS: Our data demonstrate that metformin administration modulates LH secretion as well as cortisol and allopregnanolone pulsatile release. In addition, the results demonstrate that adrenal and ovarian steroidogenic activity is greatly modulated by any change in insulin sensitivity.


Assuntos
Hipoglicemiantes/uso terapêutico , Metformina/uso terapêutico , Síndrome do Ovário Policístico/tratamento farmacológico , Adulto , Análise de Variância , Androgênios/sangue , Feminino , Teste de Tolerância a Glucose , Gonadotropinas Hipofisárias/sangue , Humanos , Hidrocortisona/sangue , Resistência à Insulina/fisiologia , Modelos Lineares , Síndrome do Ovário Policístico/metabolismo , Pregnanolona/sangue
9.
Ann N Y Acad Sci ; 1092: 103-13, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17308137

RESUMO

Hypothalamic amenorrhea (HA) is a secondary amenorrhea with no evidence of endocrine/systemic causal factors, mainly related to various stressors affecting neuroendocrine control of the reproductive axis. In clinical practice, HA is mainly associated with metabolic, physical, or psychological stress. Stress is the adaptive response of our body through all its homeostatic systems, to external and/or internal stimuli that activate specific and nonspecific physiological pathways. HA occurs generally after severe stress conditions/situations such as dieting, heavy training, or intense emotional events, all situations that can induce amenorrhea with or without body weight loss and HA is a secondary amenorrhea with a diagnosis of exclusion. In fact, the diagnosis is essentially based on a good anamnestic investigation. It has to be investigated using the clinical history of the patient: occurrence of menarche, menstrual cyclicity, time and modality of amenorrhea, and it has to be exclude any endocrine disease or any metabolic (i.e., diabetes) and systemic disorders. It is necessary to identify any stress situation induced by loss, family or working problems, weight loss or eating disorders, or physical training or agonist activity. Peculiar, though not specific, endocrine investigations might be proposed but no absolute parameter can be proposed since HA is greatly dependent from individual response to stressors and/or the adaptive response to stress. This article tries to give insights into diagnosis and putative therapeutic strategies.


Assuntos
Amenorreia/diagnóstico , Amenorreia/prevenção & controle , Doenças Hipotalâmicas/diagnóstico , Doenças Hipotalâmicas/terapia , Amenorreia/fisiopatologia , Feminino , Humanos , Doenças Hipotalâmicas/fisiopatologia
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