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1.
Int J Gynaecol Obstet ; 162(2): 525-531, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36815725

RESUMO

OBJECTIVE: To explore Rwandan women's experiences, priorities, and preferences in accessing health care for non-pregnancy-related conditions and inform development of healthcare services related to these conditions among women of reproductive age at district hospitals and health centers in Rwanda. METHODS: We used a mixed-methods, exploratory sequential design. Semi-structured qualitative interviews were conducted with Rwandan women and coded thematically. A cross-sectional quantitative survey based on the qualitative data was administered to women attending health centers. RESULTS: Seventeen interviews and 150 surveys were conducted. Women identified conditions including back pain, gynecologic cancers, and abnormal vaginal bleeding as concerns. They generally reported positive experiences while accessing health care and knowledge of accessing health care. Barriers to care were identified, including transportation costs and inability to miss work. Women expressed a desire for more control over their care and the importance of maintaining their dignity while accessing health care. CONCLUSION: These findings provide useful insights to inform development of non-pregnancy-related healthcare services for women in Rwanda according to their priorities and preferences. The reported end-user health concerns, barriers to care, and diminished control over their care point to a need to evolve health systems around user-tailored needs and design interventions optimizing access whilst promoting dignified care.


Assuntos
Prioridades em Saúde , Saúde da Mulher , Feminino , Humanos , Ruanda , Estudos Transversais , Pesquisa Qualitativa , Acessibilidade aos Serviços de Saúde
2.
Toxicol Appl Pharmacol ; 459: 116344, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36526072

RESUMO

P-glycoprotein (P-gp, encoded by the ABCB1 gene) and breast cancer resistance protein (BCRP/ABCG2) are efflux multidrug resistance (MDR) transporters localized at the syncytiotrophoblast barrier of the placenta and protect the conceptus from drug and toxin exposure throughout pregnancy. Infection is an important modulator of MDR expression and function. This review comprehensively examines the effect of infection on the MDR transporters, P-gp and BCRP in the placenta. Infection PAMPs such as bacterial lipopolysaccharide (LPS) and viral polyinosinic-polycytidylic acid (poly I:C) and single-stranded (ss)RNA, as well as infection with Zika virus (ZIKV), Plasmodium berghei ANKA (modeling malaria in pregnancy - MiP) and polymicrobial infection of intrauterine tissues (chorioamnionitis) all modulate placental P-gp and BCRP at the levels of mRNA, protein and or function; with specific responses varying according to gestational age, trophoblast type and species (human vs. mice). Furthermore, we describe the expression and localization profile of Toll-like receptor (TLR) proteins of the innate immune system at the maternal-fetal interface, aiming to better understand how infective agents modulate placental MDR. We also highlight important gaps in the field and propose future research directions. We conclude that alterations in placental MDR expression and function induced by infective agents may not only alter the intrauterine biodistribution of important MDR substrates such as drugs, toxins, hormones, cytokines, chemokines and waste metabolites, but also impact normal placentation and adversely affect pregnancy outcome and maternal/neonatal health.


Assuntos
Infecção por Zika virus , Zika virus , Gravidez , Feminino , Humanos , Camundongos , Animais , Placenta/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Distribuição Tecidual , Proteínas de Neoplasias/genética , Resistência a Múltiplos Medicamentos , Proteínas de Membrana Transportadoras/metabolismo
3.
Sci Rep ; 12(1): 10262, 2022 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-35715474

RESUMO

Limited information is available about the effect of mid-pregnancy viral infections on the placental expression of efflux transporters and offspring behavior. We hypothesized that maternal exposure to polyinosinic-polycytidylic acid [poly(I:C)], a synthetic double-stranded RNA viral mimic, would impair placental cell turnover, the expression of selected ABC transporters and adult offspring behavior. C57BL/6 mice were administered poly(I:C) (10 mg/Kg;ip) or vehicle at gestational day (GD) 13.5 (mid-pregnancy). Dams were euthanized for blood collection 4 h after injection, fetal and placental collection at GD18.5 or allowed to deliver spontaneously at term. At GD 13.5, poly(I:C) induced an acute pro-inflammatory response characterized by an increase in maternal plasma levels of IL-6, CXCL-1 and CCL-2/MCP-1. At GD 18.5, poly(I:C) decreased cell proliferation/death in the labyrinthine and increased cell death in the junctional zones, characterizing a disruption of placental cell turnover. Abca1 and Abcg1 immunolabelling was decreased in the labyrinthine zone, whereas Abca1, Abcg1 and breast cancer resistance transporter (Bcrp) expression increased in the junctional zone. Moreover, adult offspring showed motor and cognitive impairments in the Rotarod and T-water maze tests. These results indicate that viral infection during mid-pregnancy may disrupt relevant placental efflux transporters, as well as placental cell turnover and offspring behavior in adult life.


Assuntos
Transportadores de Cassetes de Ligação de ATP , Disfunção Cognitiva , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Disfunção Cognitiva/metabolismo , Feminino , Proteínas de Membrana Transportadoras/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Proteínas de Neoplasias/metabolismo , Placenta/metabolismo , Poli I-C/farmacologia , Gravidez
4.
Reprod Toxicol ; 98: 82-91, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32916274

RESUMO

Bacterial infection alters placental ABC transporters expression. These transporters provide fetal protection against circulating xenobiotics and environmental toxins present in maternal blood. We hypothesized that lipopolysaccharide (LPS-bacterial mimic) alters the yolk sac morphology and expression of key ABC transporters in a gestational-age dependent manner. Yolk sac samples from C57BL/6 mice were obtained at gestational ages (GD) 15.5 and GD18.5, 4 or 24 h after LPS exposure (150ug/kg; n = 8/group). Samples underwent morphometrical, qPCR and immunohistochemistry analysis. The volumetric proportions of the histological components of the yolk sac did not change in response to LPS. LPS increased Abcg2 expression at GD15.5, after 4 h of treatment (p < 0.05). No changes in Abca1, Abcb1a/b, Abcg1, Glut1, Snat1, Il-1ß, Ccl2 and Mif were observed. Il-6 and Cxcl1 were undetectable in the yolk sac throughout pregnancy. Abca1, breast cancer resistance protein (Bcrp, encoded by Abcg2) and P-glycoprotein (P-gp/ Abcb1a/b) were localized in the endodermal (uterine-facing) epithelium and to a lesser extent in the mesothelium (amnion-facing), whereas Abca1 was also localized to the endothelium of the yolk sac blood vessels. LPS increased the labeling area and intensity of Bcrp in the yolk sac's mesothelial cells at GD15.5 (4 h), whereas at GD18.5, the area of Bcrp labeling in the mesothelium (4 and 24 h) was decreased (p < 0.05). Bacterial infection has the potential to change yolk sac barrier function by affecting Bcrp and Abcg2 expression in a gestational-age dependent-manner. These changes may alter fetal exposure to xenobiotics and toxic substances present in the maternal circulation and in the uterine cavity.


Assuntos
Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Lipopolissacarídeos/farmacologia , Saco Vitelino/efeitos dos fármacos , Animais , Feminino , Idade Gestacional , Camundongos Endogâmicos C57BL , Gravidez , Saco Vitelino/metabolismo
5.
Clin Radiol ; 75(6): 423-432, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32081346

RESUMO

Malignant pleural mesothelioma (MPM) is a primary malignancy of the pleura and is associated with a poor outcome. The symptoms and signs of malignant mesothelioma present late in the natural history of the disease and are non-specific, making the diagnosis challenging and imaging key. In 2018, the British Thoracic Society (BTS) updated the guideline on diagnosis, staging, and follow-up of patients with MPM. These recommendations are discussed in this review of the current literature on imaging of MPM. It is estimated MPM will continue to cause serious morbidity and mortality in the UK late into the 21st century, and internationally, people continue to be exposed to asbestos. We aim to update the reader on current and future imaging strategies, which could aid early diagnosis of pleural malignancy and provide an update on staging and assessment of tumour response.


Assuntos
Diagnóstico por Imagem/normas , Mesotelioma Maligno/diagnóstico por imagem , Neoplasias Pleurais/diagnóstico por imagem , Guias de Prática Clínica como Assunto , Detecção Precoce de Câncer , Humanos , Mesotelioma Maligno/patologia , Estadiamento de Neoplasias , Neoplasias Pleurais/patologia , Sociedades Médicas
6.
J Hosp Infect ; 100(1): 54-59, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29964100

RESUMO

BACKGROUND: Pseudomonas aeruginosa (PA) is a Gram-negative environmental organism that can cause severe infection in immunosuppressed patients, including preterm neonates. In recent years, it has become common practice to screen neonates for PA colonization. AIM: To assess the value of screening neonates for PA in (1) predicting the risk of developing severe PA infection and (2) directing infection control practice. METHODS: Between August 2012 and September 2015, babies admitted to the neonatal intensive care unit (NICU) at North Bristol NHS Trust were screened routinely for PA colonization on admission and weekly thereafter. Data were also collected on babies who developed PA infection. Environmental samples from the NICU were tested for the presence of PA. Variable number tandem repeat (VNTR) typing was performed on all strains of PA from babies and the environment. FINDINGS: No babies with positive screens subsequently developed PA infection. There was no VNTR strain evidence supporting cross-infection from the environment or other babies. CONCLUSION: Screening neonates for PA did not identify babies who subsequently developed PA infection. Following cessation of screening in September 2015, there was no increase in the number of babies identified with PA infection.


Assuntos
Portador Sadio/diagnóstico , Microbiologia Ambiental , Controle de Infecções/métodos , Programas de Rastreamento/estatística & dados numéricos , Infecções por Pseudomonas/diagnóstico , Infecções por Pseudomonas/prevenção & controle , Pseudomonas aeruginosa/isolamento & purificação , Portador Sadio/microbiologia , Inglaterra/epidemiologia , Feminino , Humanos , Recém-Nascido , Unidades de Terapia Intensiva Neonatal , Masculino , Repetições Minissatélites , Tipagem Molecular , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/classificação , Pseudomonas aeruginosa/genética , Estudos Retrospectivos
7.
J Vet Intern Med ; 30(5): 1661-1666, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27527534

RESUMO

BACKGROUND: Thin body condition and weight loss are common in cats with chronic kidney disease (CKD). However, the time course and progression of weight loss before and after diagnosis have not been thoroughly evaluated. HYPOTHESIS/OBJECTIVES: To describe weight loss in cats with CKD before and after diagnosis and its relationship to survival. ANIMALS: A total of 569 cats (55.5% females and 44.5% males) with CKD from 6 US veterinary practices for which International Renal Interest Society (IRIS) stage, age, date of CKD diagnosis, and at least two body weight measurements were available. METHODS: Body weight measurements were analyzed by time windows and polynomial growth curve analysis. Survival analysis was performed by Kaplan-Meier curves and log-rank tests. RESULTS: Median age at diagnosis was 14.9 years (range, 5.0-22.8 years). Cats were categorized at diagnosis as IRIS stage 1 (n = 34 [6%]), stage 2 (n = 345 [61%]), stage 3 (n = 141 [25%]), and stage 4 (n = 49 [9%]). Median body weight at diagnosis was 4.2 kg (range, 1.6-9.9 kg). Cats lost a median of 8.9% of body weight in the 12 months before diagnosis, but weight loss was already present 3 years before diagnosis and accelerated after diagnosis of CKD. Cats <4.2 kg at the time of diagnosis had significantly shorter survival time compared to cats ≥ 4.2 kg at diagnosis (P < .0001). CONCLUSIONS AND CLINICAL IMPORTANCE: Weight loss can be detected in cats before diagnosis of CKD, accelerates after diagnosis, and is associated with shorter survival. Tracking body weight may help clinicians in earlier diagnosis of CKD.


Assuntos
Doenças do Gato/etiologia , Insuficiência Renal Crônica/veterinária , Redução de Peso , Animais , Gatos , Feminino , Masculino , Insuficiência Renal Crônica/complicações , Fatores de Tempo
8.
J Neuroendocrinol ; 28(3): 12360, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26718627

RESUMO

P-glycoprotein (P-gp) encoded by Abcb1 provides protection to the developing brain from xenobiotics. P-gp in brain endothelial cells (BECs) derived from the developing brain microvasculature is up-regulated by glucocorticoids and inhibited by pro-inflammatory cytokines in vitro. However, little is known about how prenatal maternal glucocorticoid treatment can affect Abcb1/P-gp function and subsequent cytokine regulation in foetal BECs. We hypothesised that glucocorticoid exposure increases Abcb1/P-gp in the foetal brain microvasculature and enhances the sensitivity of Abcb1/P-gp in BECs to the inhibitory effects of cytokines. BECs isolated from dexamethasone- or vehicle-exposed foetal guinea pigs were cultured and treated with interleukin-1ß, interleukin-6 or tumour necrosis factor-α, and Abcb1/P-gp expression and function were assessed. Prenatal dexamethasone exposure significantly increased Abcb1/P-gp expression/activity and cytokine receptor levels in BECs of the foetal brain microvasculature. Foetal dexamethasone exposure in vivo also increased the subsequent responsiveness of BECs to pro-inflammatory cytokines in vitro. In conclusion, maternal treatment with synthetic glucocorticoids appears to prematurely mature P-gp mediated drug resistance at the foetal BBB in vivo and profoundly impact the subsequent responsiveness of P-gp to pro-inflammatory cytokines in the foetal BEC. The significance of these findings to foetal brain protection against xenobiotics and other P-gp substrates in vivo requires further elaboration. However, the results of the present study may have implications for human pregnancy and foetal brain protection, particularly in cases of preterm birth combined with infection.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Barreira Hematoencefálica/embriologia , Barreira Hematoencefálica/metabolismo , Citocinas/farmacologia , Glucocorticoides/farmacologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Células Cultivadas , Dexametasona/farmacologia , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Cobaias , Mediadores da Inflamação/farmacologia , Masculino , Gravidez , Efeitos Tardios da Exposição Pré-Natal/genética , Efeitos Tardios da Exposição Pré-Natal/metabolismo
9.
Hum Reprod Update ; 22(2): 164-81, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26545808

RESUMO

BACKGROUND: The transmembrane ATP-binding cassette (ABC) transporters actively efflux an array of clinically relevant compounds across biological barriers, and modulate biodistribution of many physiological and pharmacological factors. To date, over 48 ABC transporters have been identified and shown to be directly and indirectly involved in peri-implantation events and fetal/placental development. They efflux cholesterol, steroid hormones, vitamins, cytokines, chemokines, prostaglandins, diverse xenobiotics and environmental toxins, playing a critical role in regulating drug disposition, immunological responses and lipid trafficking, as well as preventing fetal accumulation of drugs and environmental toxins. METHODS: This review examines ABC transporters as important mediators of placental barrier functions and key reproductive processes. Expression, localization and function of all identified ABC transporters were systematically reviewed using PubMed and Google Scholar websites to identify relevant studies examining ABC transporters in reproductive tissues in physiological and pathophysiological states. Only reports written in English were incorporated with no restriction on year of publication. While a major focus has been placed on the human, extensive evidence from animal studies is utilized to describe current understanding of the regulation and function of ABC transporters relevant to human reproduction. RESULTS: ABC transporters are modulators of steroidogenesis, fertilization, implantation, nutrient transport and immunological responses, and function as 'gatekeepers' at various barrier sites (i.e. blood-testes barrier and placenta) against potentially harmful xenobiotic factors, including drugs and environmental toxins. These roles appear to be species dependent and change as a function of gestation and development. The best-described ABC transporters in reproductive tissues (primarily in the placenta) are the multidrug transporters p-glycoprotein and breast cancer-related protein, the multidrug resistance proteins 1 through 5 and the cholesterol transporters ABCA1 and ABCG1. CONCLUSIONS: The ABC transporters have various roles across multiple reproductive tissues. Knowledge of efflux direction, tissue distribution, substrate specificity and regulation of the ABC transporters in the placenta and other reproductive tissues is rapidly expanding. This will allow better understanding of the disposition of specific substrates within reproductive tissues, and facilitate development of novel treatments for reproductive disorders as well as improved approaches to protecting the developing fetus.


Assuntos
Transportadores de Cassetes de Ligação de ATP/fisiologia , Reprodução/fisiologia , Transportadores de Cassetes de Ligação de ATP/genética , Animais , Blastocisto/metabolismo , Desenvolvimento Embrionário/genética , Feminino , Humanos , Placenta/metabolismo , Gravidez , Reprodução/genética , Distribuição Tecidual
10.
Int J Obes (Lond) ; 39(4): 614-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25512364

RESUMO

BACKGROUND: Poor inhibitory control is associated with overeating and/or obesity in school-age children, adolescents and adults. The current study examined whether an objective and reliable marker of response inhibition, the stop-signal reaction time (SSRT), is associated with body mass index (BMI) z-scores and/or food intake during a snack test in pre-school children. METHODS: The current sample consisted of 193 pre-school children taking part in a longitudinal study of early brain development (Maternal Adversity, Vulnerability and Neurodevelopment (the MAVAN project)). Linear mixed-effect models were used to examine whether the SSRT measured at age 48 months associated with BMI z-scores and/or dietary intake during a laboratory-based snack test. RESULTS: After controlling for significant covariates including maternal BMI, there was a significant gender by SSRT interaction effect in predicting 48-month BMI z-scores. Post-hoc analysis revealed an association between longer SSRTs (poor response inhibition) and higher BMIs in girls but not boys. Across both girls and boys, longer SSRTs were associated with greater intake of carbohydrates and sugars during the snack test. The association between SSRT scores and BMI z-scores in girls was not statistically mediated by carbohydrate or sugar intake. CONCLUSIONS: At 48 months of age, slower response inhibition on the Stop-Signal Task associates with higher BMI z-scores in girls, and with higher intake of carbohydrates and sugars during a snack test across both genders. Ongoing follow-up of these children will help clarify the implications of these associations for longer term macronutrient intake, eating-related pathology and/or pathological weight gain over time.


Assuntos
Ingestão de Alimentos/psicologia , Hiperfagia/psicologia , Obesidade Infantil/prevenção & controle , Tempo de Reação , Lanches/psicologia , Índice de Massa Corporal , Canadá/epidemiologia , Pré-Escolar , Ingestão de Alimentos/fisiologia , Comportamento Alimentar , Feminino , Humanos , Estudos Longitudinais , Masculino , Obesidade Infantil/epidemiologia , Obesidade Infantil/psicologia , Valor Preditivo dos Testes , Aumento de Peso
11.
Placenta ; 35(5): 324-30, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24685282

RESUMO

INTRODUCTION: The placenta contains efflux transporters, including P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP), that limit the passage of xenobiotics, certain hormones and nutrients from the maternal to the fetal circulation. The expression of these transporters changes with gestational age, yet the mechanisms involved remain unknown. However, the changes in P-gp and BCRP transporter expression coincide with those of oxygen tension in the placenta, and oxygen tension has been shown to modulate P-gp and BCRP expression in other tissues. The objective of this study was to investigate the effects of oxygen tension on P-gp and BCRP expression in the term human placenta. METHODS: Following equilibration in culture (96 h), term placental explants (n = 7) were cultured in 3% or 20% oxygen for 24 and 48 h. Culture medium was collected every 24 h to measure lactate dehydrogenase (LDH; explant viability) and human chorionic gonadotropin (hCG; syncytiotrophoblast function). P-gp (encoded by ABCB1) and BCRP (encoded by ABCG2) protein and mRNA, as well as VEGFA mRNA were measured using western blot and qRT-PCR. P-gp localization was determined using immunofluorescence. RESULTS: Oxygen tension had a significant effect on P-gp expression, with ABCB1/P-gp mRNA and protein levels increased in the hypoxic condition (3% O2) after 48 h (p < 0.05). VEGFA mRNA was elevated by hypoxia at both 24 and 48 h (p < 0.05). In contrast, placental ABCG2/BCRP mRNA and protein expression were stable with changes in oxygen tension. We identified profound differences in the glycosylation of P-gp between cultured and non-cultured placental tissue, with cultured explants expressing deglycosylated P-gp. CONCLUSIONS: These findings demonstrate that, at term, the expression of placental P-gp, is regulated by oxygen tension. This suggests that changes in oxygenation of the placenta in the third trimester may alter levels of placental P-gp, and in doing so alter fetal exposure to P-gp substrates, including xenobiotics and certain hormones.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Transportadores de Cassetes de Ligação de ATP/metabolismo , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Proteínas de Neoplasias/metabolismo , Oxigênio/administração & dosagem , Placenta/efeitos dos fármacos , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Gonadotropina Coriônica/metabolismo , Feminino , Idade Gestacional , Humanos , L-Lactato Desidrogenase/metabolismo , Placenta/metabolismo , Gravidez , Terceiro Trimestre da Gravidez , Trofoblastos/metabolismo
12.
Placenta ; 34(9): 817-23, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23790363

RESUMO

INTRODUCTION: The multidrug resistance proteins, P-glycoprotein (P-gp, encoded by the ABCB1 gene) and breast cancer resistance protein (BCRP, encoded by ABCG2) are highly expressed in the first trimester placenta. These transporters protect the fetus from exposure to maternally derived toxins and xenobiotics. Since oxygen is a regulator of multidrug resistance in various tissues, we hypothesized that changes in oxygen tension alter placental ABCB1/P-gp and ABCG2/BCRP expression in the first trimester. METHODS: Placental specimens were collected from first (n = 7), second (n = 5) and term pregnancies (n = 5). First trimester placental villous explants were incubated (24 or 48 h) in different oxygen tension (3-20%). ABCB1, ABCG2 and VEGFA mRNA expression levels were assessed by RT-PCR and protein was localized by IHC. RESULTS: ABCB1 is expressed most highly in the first trimester placenta (p < 0.05), whereas ABCG2 expression does not change significantly over pregnancy. P-gp and BCRP staining is present in the syncytiotrophoblast and in cytotrophoblasts. ABCG2 mRNA is increased in hyperoxic (20%) conditions after 48 h (p < 0.05). In contrast, hypoxia (3%) did not change ABCB1 mRNA expression but significantly increased VEGFA mRNA (p < 0.05). Hypoxia resulted in increased BCRP staining in cytotrophoblasts and in the microvillous membrane of the syncytium. Whereas, hypoxia resulted in increased P-gp staining in proliferating cytotrophoblasts. CONCLUSION: We conclude that placental multidrug resistance expression, specifically ABCG2, is regulated by oxygen tension in the first trimester. It is possible that changes in placental oxygen supply are capable of altering fetal drug exposure especially during early pregnancy.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Transportadores de Cassetes de Ligação de ATP/metabolismo , Resistência a Múltiplos Medicamentos , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Neoplasias/metabolismo , Oxigênio/metabolismo , Placenta/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Subfamília B de Transportador de Cassetes de Ligação de ATP , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/biossíntese , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/biossíntese , Transportadores de Cassetes de Ligação de ATP/genética , Hipóxia Celular , Feminino , Células Gigantes/citologia , Células Gigantes/efeitos dos fármacos , Células Gigantes/metabolismo , Humanos , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Placenta/citologia , Placenta/efeitos dos fármacos , Placentação , Gravidez , Primeiro Trimestre da Gravidez , Segundo Trimestre da Gravidez , Terceiro Trimestre da Gravidez , RNA Mensageiro/metabolismo , Bancos de Tecidos , Técnicas de Cultura de Tecidos , Trofoblastos/citologia , Trofoblastos/efeitos dos fármacos , Trofoblastos/metabolismo , Fator A de Crescimento do Endotélio Vascular/biossíntese , Fator A de Crescimento do Endotélio Vascular/genética
13.
Br J Radiol ; 85(1015): e229-37, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22745208

RESUMO

OBJECTIVES: This study aimed to clarify the number and cause of incidental findings detected on positron emission tomography (PET)/CT in patients undergoing investigation for presumed lung cancer. METHODS: The scan reports from PET/CT studies performed for patients with lung cancer under National Institute for Clinical Evidence guidelines from January 2006 until March 2008 were retrospectively reviewed. Incidental findings were followed up by a combination of case note review, clinician feedback, colonoscopy database, histopathology and follow-up imaging. RESULTS: 818 patients were investigated for lung cancer in the study period. 197 incidental findings were found in 175 (21%) patients. The subsequent investigation of 108 lesions confirmed a pathological correlation in 71 (66%) cases. A second primary malignancy was found in 10 patients within the bowel (6), breast (2), tongue (1) and stomach (1). A pre-malignant lesion was confirmed in 25 cases (24 large bowel tubulovillous adenomas and a follicular thyroid lesion). A further 41 (5%) benign abnormalities were detected at multiple sites; the thyroid gland was the single most frequently affected site (14 abnormalities). There were 36 (4.4%) false-positive reported findings, including 17 in the region of the pharynx and larynx and 12 within the large bowel. CONCLUSIONS: Overall, 9.2% of patients with suspected or known lung cancer having PET/CT had a confirmed incidental finding. A malignant or pre-malignant lesion was found in 1.2% and 3.0%, respectively. These were mostly located within the gastrointestinal tract. The majority of false-positive incidental findings were located in the larynx and pharynx. Uptake in these regions is unlikely to be significant in the absence of a CT morphological correlation.


Assuntos
Achados Incidentais , Neoplasias Pulmonares/diagnóstico por imagem , Imagem Multimodal/métodos , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X , Adulto , Idoso , Estudos de Coortes , Neoplasias do Colo/diagnóstico por imagem , Neoplasias do Colo/epidemiologia , Feminino , Fluordesoxiglucose F18 , Seguimentos , Humanos , Incidência , Neoplasias Laríngeas/diagnóstico por imagem , Neoplasias Laríngeas/epidemiologia , Neoplasias Pulmonares/diagnóstico , Masculino , Pessoa de Meia-Idade , Neoplasias Parotídeas/diagnóstico por imagem , Neoplasias Parotídeas/epidemiologia , Estudos Retrospectivos , Medição de Risco , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/epidemiologia
14.
Placenta ; 33(3): 137-42, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22265855

RESUMO

The human placenta has a number of protective mechanisms that help to prevent potentially harmful compounds from entering the fetal compartment. Two important transporter proteins are phospho-glycoprotein (P-gp) and breast cancer resistance protein (BCRP) which are mainly expressed in the syncytiotrophoblast where they actively extrude a wide range of xenobiotics. The expression profile of these transporters varies with advancing gestation. P-gp has been shown to decline near term, leaving the fetus susceptible to potentially teratogenic drugs commonly administered to pregnant women (i.e., synthetic glucocorticoids, selective serotonin reuptake inhibitors, glyburide, antiretrovirals, etc.). Drug transporter expression is regulated by a number of transcription factors, and steroid hormones present during pregnancy, such as progesterone, estrogen and corticosteroids. Drug transporter levels have also been found to be altered in pathological pregnancies (preterm, pre-eclampsia, growth restriction and infection). Genetic variation in the genes that encode these drug transporters can significantly alter transporter function and may play a significant role in determining the susceptibility of a fetus to maternally-administered therapeutic drugs. Understanding the regulation of placental drug transporters in normal and pathological pregnancies is critical to further our knowledge of fetal development, and may lead to the development of more selectively-targeted maternal and fetal drug treatments.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Doenças Fetais/induzido quimicamente , Doenças Fetais/prevenção & controle , Proteínas de Membrana Transportadoras/fisiologia , Preparações Farmacêuticas/metabolismo , Placenta/metabolismo , Animais , Transporte Biológico/genética , Transporte Biológico/fisiologia , Feminino , Doenças Fetais/genética , Feto/efeitos dos fármacos , Feto/metabolismo , Humanos , Troca Materno-Fetal/efeitos dos fármacos , Troca Materno-Fetal/genética , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Placenta/fisiologia , Gravidez
15.
Colorectal Dis ; 14(2): e56-63, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21831171

RESUMO

AIM: (18)Fluorodeoxyglucose ((18)FDG) positron emission tomography/computed tomography (PET/CT) is an established part of staging in a wide variety of malignancies. Incidental abnormal uptake of (18)FDG of unknown significance is frequently encountered. Therefore, we investigated patients with abnormal colonic uptake of (18)FDG, determined by PET/CT images, using colonoscopy. METHOD: The radiology reports of all patients referred to a tertiary referral centre for a PET/CT scan were reviewed retrospectively. Patients with abnormal colonic uptake of (18)FDG were identified and the PET/CT findings were correlated with colonoscopic findings. RESULTS: Of 555 consecutive patients identified over a 26-month period, 53 had abnormal colonic uptake of (18)FDG, as determined by PET/CT images. Twenty-nine were not investigated following discussion in a specialist multidisciplinary (MDT) meeting, according to local protocol. Twenty out of 24 patients investigated by endoscopy had a colonic lesion correlating to the site identified on the PET/CT image: 16 patients had tubulovillous adenomas (nine of which were > 10 mm), two had invasive adenocarcinomas, two had diverticular disease and one had collagenous colitis; no colonic lesion was detected in three. These findings were incidental and not related to the primary diagnosis for which the scan was being performed. Accordingly, a positive predictive value of 83% is associated with the finding of abnormal uptake of (18)FDG on PET/CT images. CONCLUSION: Incidental abnormal colonic uptake of (18)FDG, determined by a PET/CT scan requires definitive colonic investigation in patients suitable for further treatment because significant colonic pathology is frequently identified. The benefit of this approach should be discussed in specialist MDT meetings and tailored to each patient; however, national guidelines for management are required.


Assuntos
Adenocarcinoma/diagnóstico por imagem , Adenoma/diagnóstico por imagem , Neoplasias do Colo/diagnóstico por imagem , Pólipos do Colo/diagnóstico por imagem , Imagem Multimodal , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X , Adenocarcinoma/patologia , Adenocarcinoma/terapia , Adenoma/patologia , Adenoma/terapia , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Neoplasias do Colo/patologia , Neoplasias do Colo/terapia , Pólipos do Colo/patologia , Pólipos do Colo/terapia , Colonoscopia , Feminino , Fluordesoxiglucose F18 , Humanos , Achados Incidentais , Masculino , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Valor Preditivo dos Testes , Compostos Radiofarmacêuticos , Estudos Retrospectivos
16.
Am J Geriatr Pharmacother ; 9(5): 286-309, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21840265

RESUMO

BACKGROUND: Urinary tract infections (UTIs) are a common problem in the elderly population. The spectrum of disease varies from a relatively benign cystitis to potentially life-threatening pyelonephritis. OBJECTIVE: This review covers the management of asymptomatic bacteriuria, acute uncomplicated cystitis, acute uncomplicated pyelonephritis, antibiotic resistance, catheter-associated bacteriuria/symptomatic UTIs, and antibiotic prophylaxis for recurrent infections in elderly men and women. METHODS: Literature was obtained from English-language searches of MEDLINE (1966-April 2011), Cochrane Library, BIOSIS (1993-April 2011), and EMBASE (1970-April 2011). Further publications were identified from citations of resulting articles. Search terms included, but were not limited to, urinary tract infections, asymptomatic bacteriuria, acute uncomplicated cystitis, acute uncomplicated pyelonephritis, antibiotic resistance, catheter associated urinary tract infections, recurrent urinary tract infections, and elderly. RESULTS: The prevalence of UTIs in elderly women depends on the location in which these women are living. For elderly women living in the community, UTIs compromise the second most common infection, whereas in residents of long-term care facilities (LTCFs) and hospitalized subjects, it is the number one cause of infection. The spectrum of patient presentation varies from classic signs and symptoms in the independent elderly population to atypical presentations, including increased lethargy, delirium, blunted fever response, and anorexia. Although there are few guidelines specifically directed toward the management of UTIs in the elderly population, therapy generally mirrors the recommendations for the younger adult age groups. When choosing a treatment regimen, special attention must be given to the severity of illness, living conditions, existing comorbidities, presence of external devices, local antibiotic resistance patterns, and the ability of the patient to comply with therapy. CONCLUSIONS: Improved guidelines for the diagnosis and management of UTIs in the elderly population are needed. Better techniques to evaluate and prevent catheter-associated bacteriuria and UTIs await improved diagnostic modalities and catheter technologies. Alternative methods for prophylaxis of patients who suffer from recurrent infections must be found while minimizing the risk of developing or propagating antibiotic resistance.


Assuntos
Envelhecimento , Infecções Urinárias/terapia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Criança , Medicina Baseada em Evidências , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Guias de Prática Clínica como Assunto , Medição de Risco , Fatores de Risco , Prevenção Secundária , Resultado do Tratamento , Infecções Urinárias/diagnóstico , Infecções Urinárias/epidemiologia , Infecções Urinárias/microbiologia , Adulto Jovem
17.
Parkinsons Dis ; 2010: 427810, 2010 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-20976085

RESUMO

The present study evaluated whether the unilateral 6-hydroxydopamine (6-OHDA) model of Parkinson's disease produces autonomic deficits. Autonomic parameters were assessed by implanting a small radiofrequency telemetry device which measured heart rate variability (HRV), diurnal rhythms of heart rate (HR), core body temperature (cBT) and locomotor activity (LA). Rats then received 6-OHDA lesion or sham surgery. 6-OHDA lesioned rats exhibited head and body axis biases, defective sensorimotor function ("disengage" test), and prominent apomorphine rotation (all P < .05 versus controls). Diurnal rhythm of HR was lower for 6-OHDA lesioned rats (n = 8) versus controls (n = 6; P < .05). Whilst HR decreased similarly in both groups during the day, there was a greater decrease in HR for the 6-OHDA lesioned rats at night (by 38 b.p.m. relative to 17 b.p.m. for controls). LA and cBT did not differ between surgery groups. This study indicates the unilateral 6-OHDA model of PD shows subtle signs of cardiovascular autonomic dysfunction.

18.
Toxicology ; 278(3): 268-76, 2010 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-20851732

RESUMO

Lactose and food intolerance cause a wide range of gut and systemic symptoms, including gas, gut pain, diarrhoea or constipation, severe headaches, severe fatigue, loss of cognitive functions such as concentration, memory and reasoning, muscle and joint pain, heart palpitations, and a variety of allergies (Matthews and Campbell, 2000; Matthews et al., 2005; Waud et al., 2008). These can be explained by the production of toxic metabolites from gut bacteria, as a result of anaerobic digestion of carbohydrates and other foods, not absorbed in the small intestine. These metabolites include alcohols, diols such as butan 2,3 diol, ketones, acids, and aldehydes such as methylglyoxal (Campbell et al., 2005, 2009). These 'toxins' induce calcium signals in bacteria and affect their growth, thereby acting to modify the balance of microflora in the gut (Campbell et al., 2004, 2007a,b). These bacterial 'toxins' also affect signalling mechanisms in cells around the body, thereby explaining the wide range of symptoms in people with food intolerance. This new mechanism also explains the most common referral to gastroenterologists, irritable bowel syndrome (IBS), and the illness that afflicted Charles Darwin for 50 years (Campbell and Matthews, 2005a,b). We propose it will lead to a new understanding of the molecular mechanism of type 2 diabetes and some cancers.


Assuntos
Bactérias/metabolismo , Carboidratos da Dieta/toxicidade , Alimentos , Gastroenteropatias/microbiologia , Síndrome do Intestino Irritável/microbiologia , Intolerância à Lactose/microbiologia , Bactérias/efeitos dos fármacos , Toxinas Bacterianas/toxicidade , Sinalização do Cálcio/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Carboidratos da Dieta/metabolismo , Expressão Gênica/efeitos dos fármacos , Humanos , Aldeído Pirúvico/toxicidade
19.
Placenta ; 31(5): 351-7, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20347140

RESUMO

Recent studies have illustrated the importance of placental drug transport proteins, such as P-glycoprotein (Pgp) and breast cancer resistance protein (BCRP) in limiting fetal exposure to drugs and toxins. Moreover, increasing evidence supports a role for Pgp and BCRP in the normal development and physiological function of the placenta. Several single nucleotide polymorphisms (SNPs) in the genes encoding Pgp and BCRP have been described and are associated with altered protein expression, transporter activity, and clinical outcome in studies focusing on tissues other than the placenta. This review aims to summarize current research regarding the association between these polymorphisms and expression and function in the placenta. The influence of these genotypes on fetal drug exposure and altered placental physiology or development is also presented. To date, evidence suggests that SNPs in both ABCB1 and ABCG1 can alter expression of their respective protein; however, the functional significance of these polymorphisms is less clear. An understanding of this genotype-phenotype relationship will allow for prediction of susceptible or favorable genotypes in order to personalize medication choices to minimize fetal exposure to teratogens, or to maximize pharmacological therapy to the fetus.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/genética , Resistência a Múltiplos Medicamentos/genética , Feto/metabolismo , Troca Materno-Fetal/genética , Proteínas de Neoplasias/genética , Placenta/metabolismo , Polimorfismo de Nucleotídeo Único , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/metabolismo , Adulto , Transporte Biológico , Feminino , Feto/efeitos dos fármacos , Genótipo , Humanos , Troca Materno-Fetal/efeitos dos fármacos , Proteínas de Neoplasias/metabolismo , Placenta/efeitos dos fármacos , Gravidez , Xenobióticos/farmacocinética
20.
Placenta ; 31(2): 97-105, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20045184

RESUMO

Synthetic glucocorticoids (GCs) are given to women with threatened preterm labour but their administration has been linked to reduced infant birthweight. The underlying mechanisms are unknown, but impaired placental development and/or function has been implicated. The activity of the system A amino acid transporter is decreased in placentas from pregnancies complicated by fetal growth restriction. Whether GCs adversely affect placental amino acid transport is unknown. The objective of this study was to determine the regulatory effects of GCs on system A transport using a human in vitro placental explant model. Term explants (n=7) were treated with dexamethasone (DEX 10(-8)M or 10(-6)M) or vehicle for 48 h. System A activity was measured by the uptake of (14)C-N-methylated aminoisobutyric acid by explants. Explants were also processed for electron microscopy (EM), immunohistochemistry, and qRT-PCR. Lactate dehydrogenase (LDH), human chorionic gonadotropin (hCG) and human placental lactogen (hPL) release into the culture medium was measured. DEX (10(-6)M) stimulated system A activity compared to vehicle (p<0.05). System A transporter proteins were localized to the newly regenerating syncytiotrophoblast layer, but mRNA levels were unchanged with DEX treatment. DEX did not adversely affect explant viability as determined by reduced LDH release (p<0.05). DEX treatment was associated with morphological (accelerated apical microvilli formation, nuclear maturation, and increased cell organelle number) and functional (elevated hCG secretion, increased 11beta-HSD2 mRNA expression and reduced cytotrophoblast proliferation (p<0.05 for all)) markers of syncytiotrophoblast differentiation. These findings suggest that DEX stimulates system A activity and promotes syncytiotrophoblast differentiation and maturation.


Assuntos
Sistema A de Transporte de Aminoácidos/metabolismo , Diferenciação Celular/efeitos dos fármacos , Dexametasona/farmacologia , Glucocorticoides/farmacologia , Placenta/efeitos dos fármacos , Trofoblastos/efeitos dos fármacos , 11-beta-Hidroxiesteroide Desidrogenase Tipo 2/genética , 11-beta-Hidroxiesteroide Desidrogenase Tipo 2/metabolismo , Proliferação de Células/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Gonadotropina Coriônica/metabolismo , Relação Dose-Resposta a Droga , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Produtos do Gene env/genética , Produtos do Gene env/metabolismo , Humanos , Técnicas In Vitro , Antígeno Ki-67/metabolismo , Placenta/citologia , Placenta/enzimologia , Placenta/fisiologia , Gravidez , Proteínas da Gravidez/genética , Proteínas da Gravidez/metabolismo , Isoformas de Proteínas/metabolismo , Regeneração/efeitos dos fármacos , Nascimento a Termo , Fatores de Tempo , Trofoblastos/citologia , Trofoblastos/metabolismo
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