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1.
Contemp Clin Trials ; 114: 106685, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35065281

RESUMO

INTRODUCTION: Reduced testosterone levels due to androgen deprivation therapy (ADT) in prostate cancer patients cause common side effects, such as reduced muscle strength and bone density, increased fat mass, sexual dysfunction and fatigue. Short-term exercise during ADT has proven to be safe and effective in exhibiting a positive impact on body composition, sexual dysfunction and fatigue. However, there are only three randomized controlled trials that investigate one-year supervised impact exercise interventions, none of which examined follow-up effects after the intervention. Therefore, this study will conduct a one-year impact exercise intervention and assess follow-up effects up to one year later. MATERIAL AND METHODS: The aim of the randomized, controlled Burgdorf study is to assess the effects of a supervised 12-month intensive multimodal exercise intervention in comparison to a moderate aerobic exercise intervention, on muscle strength in prostate cancer patients receiving ADT. Additionally, quality of life, fatigue, body composition, erectile dysfunction, bone pain, physical activity level, endurance capacity, body-mass-index, waist and hip circumference and prostate-specific antigen- and testosterone levels will be assessed up to one year later. DISCUSSION: The Burgdorf study is the first study to conduct two different one-year supervised exercise interventions, and follow-up with patients for up to one year after the intervention. Results could provide important insights into the long-term effects of interventions on those parameters negatively affected by ADT, which could specify or newly establish care structures. TRIAL REGISTRATION: German Clinical Trials Register, DRKS00009975. Registered 2016-02-09, https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00009975.


Assuntos
Antagonistas de Androgênios , Neoplasias da Próstata , Antagonistas de Androgênios/efeitos adversos , Terapia por Exercício/métodos , Humanos , Masculino , Força Muscular , Neoplasias da Próstata/tratamento farmacológico , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto
2.
Curr Oncol ; 27(6): e596-e606, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33380875

RESUMO

Background: Evidence about the impact of marital status before hematopoietic cell transplantation (hct) on outcomes after hct is conflicting. Methods: We identified patients 40 years of age and older within the Center for International Blood and Marrow Transplant Research registry who underwent hct between January 2008 and December 2015. Marital status before hct was declared as one of: married or living with a partner, single (never married), separated or divorced, and widowed. We performed a multivariable analysis to determine the association of marital status with outcomes after hct. Results: We identified 10,226 allogeneic and 5714 autologous hct cases with, respectively, a median follow-up of 37 months (range: 1-102 months) and 40 months (range: 1-106 months). No association between marital status and overall survival was observed in either the allogeneic (p = 0.58) or autologous (p = 0.17) setting. However, marital status was associated with grades 2-4 acute graft-versus-host disease (gvhd), p < 0.001, and chronic gvhd, p = 0.04. The risk of grades 2-4 acute gvhd was increased in separated compared with married patients [hazard ratio (hr): 1.13; 95% confidence interval (ci): 1.03 to 1.24], and single patients had a reduced risk of grades 2-4 acute gvhd (hr: 0.87; 95% ci: 0.77 to 0.98). The risk of chronic gvhd was lower in widowed compared with married patients (hr: 0.82; 95% ci: 0.67 to 0.99). Conclusions: Overall survival after hct is not influenced by marital status, but associations were evident between marital status and grades 2-4 acute and chronic gvhd. To better appreciate the effects of marital status and social support, future research should consider using validated scales to measure social support and patient and caregiver reports of caregiver commitment, and to assess health-related quality of life together with health care utilization.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Doença Enxerto-Hospedeiro/epidemiologia , Doença Enxerto-Hospedeiro/etiologia , Humanos , Estado Civil , Qualidade de Vida
3.
Ann Oncol ; 28(2): 386-392, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-28426102

RESUMO

Background: Comprehensive studies on neutropenia and infection-related complications in patients with acute lymphoblastic leukemia (ALL) are lacking. Patients and methods: We evaluated infection-related complications that were grade ≥3 on National Cancer Institute's Common Terminology Criteria for Adverse Events (version 3.0) and their risk factors in 409 children with newly diagnosed ALL throughout the treatment period. Results: Of the 2420 infection episodes, febrile neutropenia and clinically or microbiologically documented infection were seen in 1107 and 1313 episodes, respectively. Among documented infection episodes, upper respiratory tract was the most common site (n = 389), followed by ear (n = 151), bloodstream (n = 147), and gastrointestinal tract (n = 145) infections. These episodes were more common during intensified therapy phases such as remission induction and reinduction, but respiratory and ear infections, presumably viral in origin, also occurred during continuation phases. The 3-year cumulative incidence of infection-related death was low (1.0±0.9%, n = 4), including 2 from Bacillus cereus bacteremia. There was no fungal infection-related mortality. Age 1-9.9 years at diagnosis was associated with febrile neutropenia (P = 0.002) during induction and febrile neutropenia and documented infection (both P < 0.001) during later continuation. White race was associated with documented infection (P = 0.034) during induction. Compared with low-risk patients, standard- and high-risk patients received more intensive therapy during early continuation and had higher incidences of febrile neutropenia (P < 0.001) and documented infections (P = 0.043). Furthermore, poor neutrophil surge after dexamethasone pulses during continuation, which can reflect the poor bone marrow reserve, was associated with infections (P < 0.001). Conclusions: The incidence of infection-related death was low. However, young age, white race, intensive chemotherapy, and lack of neutrophil surge after dexamethasone treatment were associated with infection-related complications. Close monitoring for prompt administration of antibiotics and modification of chemotherapy should be considered in these patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neutropenia Febril Induzida por Quimioterapia/mortalidade , Neutropenia Febril Induzida por Quimioterapia/terapia , Criança , Pré-Escolar , Dexametasona/administração & dosagem , Feminino , Humanos , Lactente , Contagem de Leucócitos , Masculino , Neutrófilos/imunologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/imunologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Infecções Respiratórias/induzido quimicamente , Infecções Respiratórias/mortalidade , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento , Vincristina/administração & dosagem
4.
Internist (Berl) ; 58(3): 226-232, 2017 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-28108748

RESUMO

Bleeding in the upper gastrointestinal (GI) tract is a frequent and complex emergency. There are guidelines for acute medical treatment, established endoscopic treatment as well as surgical and radiological rescue procedures. Nevertheless, the mortality of the upper GI tract bleeding is high, which is due to the fact that affected patients often have serious preexisting illnesses.


Assuntos
Hemorragia Gastrointestinal/terapia , Trato Gastrointestinal Superior , Emergências , Endoscopia Gastrointestinal , Hemorragia Gastrointestinal/mortalidade , Humanos
5.
Acta Gastroenterol Belg ; 80(1): 25-30, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29364094

RESUMO

BACKGROUND: Leading causative factors of peptic ulcer disease (PUD) in the general population are infection with Helicobacter pylori (HP) and exposure to non-steroidal anti-inflammatory drugs (NSAID). We hypothesized that this may be different in transplant recipients given increased exposure of immunosuppressive and anti-microbial drugs. METHODS: We performed a retrospective single center analysis of all patients presenting with PUD to the endoscopy unit at a tertiary care and transplant center in Germany between 2006 and 2013. PUD was diagnosed by upper endoscopy. HP was identified by biopsy and histology. Organ transplant recipients were compared to non-transplant recipients (control group). RESULTS: 66 patients with PUD were identified in the study period. 12% (44/366) had previously received an organ transplant. 7% (3/44) of transplant recipients were found to be positive for HP compared to 25% (81/322) in the control group (p=0.007). Even when excluding patients taking proton-pump-inhibitors (PPI) from the analysis rates were similar with 30% (65/214) of the ulcers being HP positive in the control group compared to 14% (1/7) in transplant recipients (p=0.006). Furthermore, in the transplant recipient group rates of being in intensive care, concurrent PPI and concurrent antibiotic medication were significantly higher than in the control group. CONCLUSION: Organ transplant recipients with PUD have lower rates of Helicobacter pylori positivity compared to the general population.


Assuntos
Infecções por Helicobacter/complicações , Helicobacter pylori , Transplante de Órgãos , Úlcera Péptica/microbiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/uso terapêutico , Estudos de Casos e Controles , Feminino , Infecções por Helicobacter/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Inibidores da Bomba de Prótons/uso terapêutico , Estudos Retrospectivos , Adulto Jovem
6.
Nanoscale ; 8(16): 8607-17, 2016 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-27049842

RESUMO

Organic materials such as phthalocyanine-based systems present a great potential for organic device applications due to the possibility of integrating films of different organic materials to create organic heterostructures which combine the electrical capabilities of each material. This opens the possibility to precisely engineer and tune new electrical properties. In particular, similar transition metal phthalocyanines demonstrate hybridization and charge transfer properties which could lead to interesting physical phenomena. Although, when considering device dimensions, a better understanding and control of the tuning of the transport properties still remain in the focus of research. Here, by employing conductive atomic force microscopy techniques, we provide an insight about the nanoscale electrical properties and transport mechanisms of MnPc and fluorinated phthalocyanines such as F16CuPc and F16CoPc. We report a transition from typical diode-like transport mechanisms for pure MnPc thin films to space-charge-limited current transport regime (SCLC) for Pc-based heterostructures. The controlled addition of fluorinated phthalocyanine also provides highly uniform and symmetric-polarized transport characteristics with conductance enhancements up to two orders of magnitude depending on the polarization. We present a method to spatially map the mobility of the MnPc/F16CuPc structures with a nanoscale resolution and provide theoretical calculations to support our experimental findings. This well-controlled nanoscale tuning of the electrical properties for metal transition phthalocyanine junctions stands as key step for future phthalocyanine-based electronic devices, where the low dimension charge transfer, mediated by transition metal atoms could be intrinsically linked to a transfer of magnetic moment or spin.

7.
Bone Marrow Transplant ; 51(9): 1233-40, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27088381

RESUMO

Hematopoietic cell transplantation (HCT) is a procedure that can significantly influence the socioeconomic wellbeing of patients, caregivers and their families. Among 30 allogeneic HCT recipients and their caregivers enrolled on a pilot study evaluating the feasibility of studying financial impact of HCT, 16 agreed to participate in the long-term phase, completed a baseline questionnaire and received phone interviews at 6, 12, 18 and 24 months post HCT. Analyses showed that by 2 years post HCT, 54% of patients who previously contributed to household earnings had not returned to work and 80% of patients/caregivers reported transplant as having moderate to great impact on household income. However, patients' levels of confidence in their abilities to meet household financial obligations increased from baseline to 2 years. A relatively large proportion of patients reported inability to pay for medical care through this time period. Case studies demonstrated that patients' individual perceptions of the financial impact of HCT varies considerably, regardless of actual income. We demonstrate the feasibility of conducting a study to evaluate the financial impact of allogeneic HCT through 2 years post transplantation. Some patients/caregivers continue to experience a significant long-term financial burden after this procedure. Our study lays the foundation for a larger evaluation of patient/caregiver financial burden associated with HCT.


Assuntos
Cuidadores/economia , Efeitos Psicossociais da Doença , Transplante de Células-Tronco Hematopoéticas/economia , Emprego/economia , Saúde da Família/economia , Humanos , Projetos Piloto , Inquéritos e Questionários , Transplante Homólogo/economia
9.
Chem Commun (Camb) ; 50(65): 9060-3, 2014 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-24819240

RESUMO

The kind of surface MoOX structures on Al2O3-SiO2 was found to determine propene selectivity in the metathesis of ethylene and 2-butene. Compared to isolated tetrahedral MoOX species, their polymerized octahedral counterparts show significantly lower activity for isomerisation of 2- to 1-butene thus hindering non-selective metathesis of these butenes. In addition, they reveal higher ability to engage ethylene in propene formation.

10.
J Viral Hepat ; 21(11): 769-79, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24251818

RESUMO

HCV RNA levels correlate with the long-term outcome of hepatitis C in liver transplant recipients. Nucleic acid testing (NAT) is usually used to confirm HCV reinfection and to examine viral loads after liver transplantation. HCV core antigen (HCVcoreAg) testing could be an alternative to NAT with some potential advantages including very low intra- and interassay variabilities and lower costs. The performance of HCVcoreAg testing in organ transplant recipients is unknown. We prospectively studied 1011 sera for HCV RNA and HCVcoreAg in a routine real-world setting including 222 samples obtained from patients after liver or kidney transplantation. HCV RNA and HCVcoreAg test results showed a consistency of 98% with a very good correlation in transplanted patients (r > 0.85). The correlation between HCV RNA and HCVcoreAg was higher in sera with high viral loads and in samples from patients with low biochemical disease. Patients treated with tacrolimus showed a better correlation between both parameters than individuals receiving cyclosporine A. HCV RNA/HCVcoreAg ratios did not differ between transplanted and nontransplanted patients, and HCV RNA and HCVcoreAg kinetics were almost identical during the first days after liver transplantation. HCVcoreAg testing can be used to monitor HCV viral loads in patients after organ transplantation. However, the assay is not recommended to monitor antiviral therapies.


Assuntos
Hepatite C/diagnóstico , Transplantados , Proteínas do Core Viral/sangue , Carga Viral/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Imunoensaio/métodos , Transplante de Rim , Transplante de Fígado , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , RNA Viral/sangue , Adulto Jovem
11.
Bone Marrow Transplant ; 49(2): 248-53, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24162612

RESUMO

MTX is a standard component of acute GVHD prophylaxis. However, its use can be limited by toxicity. On the basis of disease risk, we prospectively assigned 132 consecutive patients from January 2005 to February 2011 undergoing first allogeneic hematopoietic cell transplant after conditioning with fludarabine and melphalan to acute GVHD prophylaxis with tacrolimus/MTX (TAC/MTX, N=22), TAC/micro-dose MTX/mycophenolate mofetil (TAC/µMTX/MMF, N=78) or TAC/MMF (TAC/MMF, N=32), to optimize acute GVHD prevention and decrease mortality. The median (range) follow-up was 24 (0.8-60) months. The median patient ages (range) were 37 (23-63), 56 (20-68) and 54 (22-68) years (P<0.0001) for TAC/MTX, TAC/µMTX/MMF and TAC/MMF, respectively. The 100-day cumulative incidences of grade III-IV acute GVHD were 19, 23 and 49% (P=0.015), respectively. The cumulative incidences of severe chronic GVHD at 1 year were 38, 29 and 79% (P<0.001), respectively. Regimen-related toxicities were not significantly different among the three prophylaxis regimens. PFS and OS were equivalent between the TAC/MTX and TAC/µMTX/MMF arms despite significantly older patients in the latter arm, and both had superior PFS and OS than the TAC/MMF arm. Acute GVHD prophylaxis with TAC/µMTX/MMF is as effective as TAC/MTX and superior to TAC/MMF.


Assuntos
Antimetabólitos Antineoplásicos/uso terapêutico , Doença Enxerto-Hospedeiro/prevenção & controle , Melfalan/uso terapêutico , Metotrexato/uso terapêutico , Vidarabina/análogos & derivados , Doença Aguda , Adulto , Antimetabólitos Antineoplásicos/administração & dosagem , Feminino , Humanos , Masculino , Melfalan/administração & dosagem , Metotrexato/administração & dosagem , Pessoa de Meia-Idade , Vidarabina/administração & dosagem , Vidarabina/uso terapêutico , Adulto Jovem
12.
Gen Comp Endocrinol ; 190: 76-80, 2013 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-23612018

RESUMO

Opportunistic breeding has been hypothesized to evolve in response to rare or unpredictable resource pulses. In this traditional view of opportunism, individuals invest heavily in reproduction whenever conditions are permissive for breeding, perhaps at the expense of investment in survival. We term this strategy 'obligate opportunism' (OBO). We also present an additional strategy that could account for the evolution of opportunism. High mobility may allow individuals to move between rich patches of resources that are spatially or temporally unpredictable, reducing exposure to food scarcity and taking advantage of breeding opportunities. This strategy, which we term 'rich patch exploiter' (RPE), predicts that investment in survival-enhancing processes may occur at the expense of reproduction despite high resource availability. We review examples to determine which opportunists better match predictions from the OBO strategy or the RPE strategy and then review endocrine profiles in the context of the two strategies.


Assuntos
Tentilhões/metabolismo , Tentilhões/fisiologia , Animais , Corticosterona/metabolismo , Hormônio Liberador de Gonadotropina/metabolismo , Humanos
13.
Eur J Cancer ; 49(7): 1530-8, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23352440

RESUMO

BACKGROUND: Quality of life (QoL) after breast cancer is nowadays a major challenge. Complementary interventions are necessary because of frequent depression symptoms after treatment and also to favour return to activity. Besides, radio-chemotherapy has side-effects like weight gain and fatigue. Several strategies including group behavioural-educational interventions, physical training and/or dietary education, have been tested to answer these difficulties with moderate success in the long run. METHODS: Two hundred and fifty-one non-metastatic patients were accrued after chemotherapy in a prospective randomised multicenter trial between 2008 and 2010, testing a 2-week intervention in SPA centres. Intervention comprised group physical training, dietary education and physiotherapy. Selected patients were in complete remission. QoL was evaluated with SF36 questionnaire, anxiety and depression with the hospital anxiety and depression (HAD) one. Anthropometric measures and QoL evaluations were obtained before randomisation and every 6 months during 3 years. RESULTS: Two hundred and twenty patients were evaluable at 1 year. Intervention increased SF36 score by 9.5 points (p=0.000006), 4.6 (p=0.032) and 6.2 (p=0.028) respectively at 6, 12 and 24 months. Effect size (ES) was 0.63 [0.37; 0.90], 0.29 [0.03; 0.55] and 0.41 [0.04; 0.78]. Anxiety score was shortly minored by intervention (6-month ES=-0.24 [-0.42; -0.05]) and depression score more durably: ES=-0.45 [-0.72; -0.18], -0.34 [-061; -0.08], and -0.26 [-0.63; 0.11] at 6, 12 and 24 months. CONCLUSION: This 2-week group intervention seemed to durably influence QoL of breast cancer patients treated by chemotherapy. Differences, smaller at 12 months than at six, suggest that a second but shorter intervention could help maintain the 6-month benefits.


Assuntos
Neoplasias da Mama/terapia , Educação de Pacientes como Assunto/métodos , Modalidades de Fisioterapia , Qualidade de Vida , Adulto , Idoso , Neoplasias da Mama/tratamento farmacológico , Feminino , Estâncias para Tratamento de Saúde , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Inquéritos e Questionários , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
14.
Curr Pharm Biotechnol ; 14(3): 357-76, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22201597

RESUMO

Cytotoxic drugs in cancer therapy are used with the expectation of selectively killing and thereby eliminating the offending cancer cells. If they should die in an appropriate manner, the cells can also release danger signals that promote an immune reaction that reinforces the response against the cancer. The identity of these immune-enhancing danger signals, how they work extra- and intracellularly, and the molecular mechanisms by which some anti-cancer drugs induce cell death to bring about the release of danger signals are the major focus of this review. A specific group of mitocans, the vitamin E analogs that act by targeting mitochondria to drive ROS production and also promote a more immunogenic means of cancer cell death exemplify such anti-cancer drugs. The role of reactive oxygen species (ROS) production and the events leading to the activation of the inflammasome and pro-inflammatory mediators induced by dying cancer cell mitochondria are discussed along with the evidence for their contribution to promoting immune responses against cancer. Current knowledge of how the danger signals interact with immune cells to boost the anti-tumor response is also evaluated.


Assuntos
Antineoplásicos/farmacologia , Neoplasias/imunologia , Vitamina E/análogos & derivados , Vitamina E/farmacologia , Antineoplásicos/uso terapêutico , Morte Celular , Imunoterapia , Inflamassomos , Neoplasias/terapia , Espécies Reativas de Oxigênio/imunologia , Vitamina E/uso terapêutico
15.
Bone Marrow Transplant ; 48(6): 865-71, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23222378

RESUMO

Patient/caregiver out-of pocket costs associated with hematopoietic cell transplantation (HCT) are not well known. We conducted a pilot study to evaluate patient/caregiver out-of-pocket costs in the first 3 months after allogeneic HCT. Thirty patients were enrolled at three sites. Before HCT, participants completed a baseline survey regarding household income and insurance coverage. Subsequently, they maintained a paper-based diary to track daily out-of-pocket expenses for the first 3 months after HCT. Telephone interviews were conducted to follow-up on the missing/incomplete diaries and on study completion. Twenty-five patients/caregivers completed the baseline survey. Among these, the median pre-tax household income was $66 500 (range, $30-$375 000) and 48% had to temporarily relocate close to the transplant center. Insurance coverage was managed care plan (56%), Medicaid (20%), Medicare (17%) and other (8%). Twenty-two patients/caregivers completed 4 diaries; the median out-of-pocket expenses were $2440 (range, $199-$13 769). Patients/caregivers who required temporary lodging had higher out-of-pocket expenses compared with those who did not (median, $5247 vs $716). Patients/caregivers can incur substantial out-of-pocket costs over the first 3 months, especially if they need to temporarily relocate close to the transplant center. Our study lays the foundation for future research on the early and long-term financial impact of allogeneic HCT on patients/caregivers.


Assuntos
Cuidadores/economia , Transplante de Células-Tronco Hematopoéticas/economia , Seguro Saúde/economia , Adulto , Idoso , Aloenxertos , Custos e Análise de Custo , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto
16.
Dtsch Med Wochenschr ; 137(47): 2448-52, 2012 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-23152073

RESUMO

Many viruses infect hepatocytes. On the one hand an understanding of the underlying molecular mechanisms can be used to block infection by pathogenic viruses, on the other hand hepatotropic viruses can be utilized in gene therapy approaches for the directed delivery of genetic material into hepatocytes. The hepatitis C virus (HCV) follows a complex cell entry route utilizing at least four essential cell surface receptors on hepatocytes. Inhibitors of HCV cell entry are in early clinical development and could useful for the prevention of HCV reinfection of the graft after liver transplantation. Although much less is known about the cell entry of hepatitis B virus and hepatitis D virus (HBV; HDV) it can be blocked efficiently by active or passive immunization. Moreover, a highly specific lipopeptide entry inhibitor based on a fragment of the HBV envelope is in clinical development. Finally, approaches are being developed to use hepatotropic viruses to correct genetic defects in hepatocytes. Especially adeno-associated virus based vector systems have recently shown promising results in proof-of-concept studies.


Assuntos
Hepacivirus/patogenicidade , Hepatite C/virologia , Hepatócitos/virologia , Animais , Células Cultivadas , Hepatócitos/metabolismo , Humanos
17.
Front Neuroendocrinol ; 33(3): 287-300, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23041619

RESUMO

Gonadotropin-releasing hormone 1 (GnRH1) is a key regulator of the reproductive neuroendocrine system in vertebrates. Recent developments have suggested that GnRH1 neurons exhibit far greater plasticity at the cellular and molecular levels than previously thought. Furthermore, there is growing evidence that sub-populations of GnRH1 neurons in the preoptic area are highly responsive to specific environmental and hormonal conditions. In this paper we discuss findings that reveal large variation in GnRH1 mRNA and protein expression that are regulated by social cues, photoperiod, and hormonal feedback. We draw upon studies using histochemistry and immediate early genes (e.g., c-FOS/ZENK) to illustrate that specific groups of GnRH1 neurons are topographically organized. Based on data from diverse vertebrate species, we suggest that GnRH1 expression within individuals is temporally dynamic and this plasticity may be evolutionarily conserved. We suggest that the plasticity observed in other neuropeptide systems (i.e. kisspeptin) may have evolved in a similar manner.


Assuntos
Hormônio Liberador de Gonadotropina/fisiologia , Plasticidade Neuronal/fisiologia , Animais , Aves/fisiologia , Ciclídeos/fisiologia , Cricetinae , Feminino , Hormônio Liberador de Gonadotropina/biossíntese , Hormônio Liberador de Gonadotropina/química , Kisspeptinas/genética , Masculino , Neurônios , Fotoperíodo , Área Pré-Óptica/fisiologia , RNA Mensageiro/metabolismo , Reprodução/fisiologia , Estações do Ano , Ovinos/fisiologia , Territorialidade
18.
J Neuroendocrinol ; 24(2): 267-74, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22023598

RESUMO

In many seasonally reproducing animals, the experience of prolonged exposure to constant photoperiods results in the induction of a state of photorefractoriness, which is defined as a lack of responsiveness to a previously stimulatory photoperiod. The physiological and genetic processes that control photorefractoriness are not well understood; however, the hallmark of photorefractoriness is an endogenous change in the physiological response to a constant photoperiod. It is already known that preoptic area (POA) gnrh1 gene expression declines during the development of refractoriness to long-day stimulation in European starlings. We employed in situ hybridisation histochemistry to characterise changes in POA gnrh1 mRNA expression during the reinstatement of photosensitivity in female starlings. Photorefractory starlings moved to short days (8L:16D) increased optical density of gnrh1 expressing cells within 10 days. Exposure to 30 short days resulted in greater visible gnrh1 cell numbers, with no detectable change in measures of ovarian follicular volume and oviduct mass. We subsequently examined the extent of gnrh1 expression in response to photostimulation after incremental periods on short day lengths. A significant long-day-induced increase in both gnrh1 expression and ovarian and oviduct mass occurred only after at least 30 short days. These findings demonstrate that the recovery of photorefractoriness involves an increase in gnrh1 mRNA expression and expands upon our previous knowledge that the development of photosensitivity is associated with an increase in both the precursor proGnRH1-GAP and GnRH1 peptides in the POA. Importantly, the change in the brain sensitivity occurs well before such changes can be detected via variation in ovarian activity.


Assuntos
Regulação da Expressão Gênica , Hormônio Liberador de Gonadotropina/genética , Área Pré-Óptica/metabolismo , Reprodução/genética , Estações do Ano , Estorninhos/fisiologia , Adaptação Fisiológica/genética , Animais , Feminino , Previsões , Regulação da Expressão Gênica/fisiologia , Hormônio Liberador de Gonadotropina/metabolismo , Estimulação Luminosa , Fotoperíodo , Área Pré-Óptica/fisiologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reprodução/fisiologia , Estorninhos/genética , Estorninhos/metabolismo
19.
Infect Control Hosp Epidemiol ; 32(5): 490-6, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21515980

RESUMO

OBJECTIVE: To study the molecular epidemiology of vancomycin-resistant Enterococcus (VRE) colonization and to identify modifiable risk factors among patients with hematologic malignancies. SETTING: A hematology-oncology unit with high prevalence of VRE colonization. PARTICIPANTS: Patients with hematologic malignancies and hematopoietic stem cell transplantation recipients admitted to the hospital. METHODS: Patients underwent weekly surveillance by means of perianal swabs for VRE colonization and, if colonized, were placed in contact isolation. We studied the molecular epidemiology in fecal and blood isolates by pulsed-field gel electrophoresis over a 1-year period. We performed a retrospective case-control study over a 3-year period. Cases were defined as patients colonized by VRE, and controls were defined as patients negative for VRE colonization. Case patients and control patients were matched by admitting service and length of observation time. RESULTS: Molecular genotyping demonstrated the primarily polyclonal nature of VRE isolates. Colonization occurred at a median of 14 days. Colonized patients were characterized by longer hospital admissions. Previous use of ceftazidime was associated with VRE colonization (P < .001), while use of intravenous vancomycin and antibiotics with anaerobic activity did not emerge as a risk factor. There was no association with neutropenia or presence of colonic mucosal disruption, and severity of illness was similar in both groups. CONCLUSION: Molecular studies showed that in the majority of VRE-colonized patients the strains were unique, arguing that VRE acquisition was sporadic rather than resulting from a common source of transmission. Patient-specific factors, including prior antibiotic exposure, rather than breaches in infection control likely predict for risk of fecal VRE colonization.


Assuntos
Infecção Hospitalar/complicações , Infecção Hospitalar/epidemiologia , Enterococcus/genética , Infecções por Bactérias Gram-Positivas/epidemiologia , Neoplasias Hematológicas/complicações , Resistência a Vancomicina , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/uso terapêutico , Estudos de Casos e Controles , Criança , Pré-Escolar , Infecção Hospitalar/transmissão , DNA Bacteriano/análise , Eletroforese em Gel de Campo Pulsado , Enterococcus/isolamento & purificação , Feminino , Genótipo , Infecções por Bactérias Gram-Positivas/complicações , Infecções por Bactérias Gram-Positivas/microbiologia , Infecções por Bactérias Gram-Positivas/transmissão , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
20.
Sex Dev ; 5(2): 60-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21293114

RESUMO

Stochastic, environmentally and/or genetically induced disturbances in the genome-wide epigenetic reprogramming processes during male germ-cell development may contribute to male infertility. To test this hypothesis, we have studied the methylation levels of 2 paternally (H19 and GTL2) and 5 maternally methylated (LIT1, MEST, NESPAS, PEG3, and SNRPN) imprinted genes, as well as of ALU and LINE1 repetitive elements in 141 sperm samples, which were used for assisted reproductive technologies (ART), including 106 couples with strictly male-factor or combined male and female infertility and 28 couples with strictly female-factor infertility. Aberrant methylation imprints showed a significant association with abnormal semen parameters, but did not seem to influence ART outcome. Repeat methylation also differed significantly between sperm samples from infertile and presumably fertile males. However, in contrast to imprinted genes, ALU methylation had a significant impact on pregnancy and live-birth rate in couples with male-factor or combined infertility. ALU methylation was significantly higher in sperm samples leading to pregnancy and live-birth than in those that did not. Sperm samples leading to abortions showed significantly lower ALU methylation levels than those leading to the birth of a baby.


Assuntos
Metilação de DNA/fisiologia , DNA/genética , Impressão Genômica/fisiologia , Infertilidade Masculina/genética , Sequências Repetitivas de Ácido Nucleico/genética , Espermatozoides/metabolismo , Adulto , Metilação de DNA/genética , Feminino , Impressão Genômica/genética , Humanos , Fatores de Transcrição Kruppel-Like/genética , Masculino , Canais de Potássio de Abertura Dependente da Tensão da Membrana/genética , Gravidez , Proteínas/genética , RNA Longo não Codificante , Proteínas Centrais de snRNP/genética
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