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1.
Hum Genomics ; 18(1): 48, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38769549

RESUMO

BACKGROUND: After the occurrence of the COVID-19 pandemic, detection of other disseminated respiratory viruses using highly sensitive molecular methods was declared essential for monitoring the spread of health-threatening viruses in communities. The development of multiplex molecular assays are essential for the simultaneous detection of such viruses even at low concentrations. In the present study, a highly sensitive and specific multiplex one-step droplet digital PCR (RT-ddPCR) assay was developed for the simultaneous detection and absolute quantification of influenza A (IAV), influenza B (IBV), respiratory syncytial virus (RSV), and beta-2-microglobulin transcript as an endogenous internal control (IC B2M). RESULTS: The assay was first evaluated for analytical sensitivity and specificity, linearity, reproducibility, and recovery rates with excellent performance characteristics and then applied to 37 wastewater samples previously evaluated with commercially available and in-house quantitative real-time reverse transcription PCR (RT-qPCR) assays. IAV was detected in 16/37 (43%), IBV in 19/37 (51%), and RSV in 10/37 (27%) of the wastewater samples. Direct comparison of the developed assay with real-time RT-qPCR assays showed statistically significant high agreement in the detection of IAV (kappa Cohen's correlation coefficient: 0.834, p = 0.001) and RSV (kappa: 0.773, p = 0.001) viruses between the two assays, while the results for the detection of IBV (kappa: 0.355, p = 0.27) showed good agreement without statistical significance. CONCLUSIONS: Overall, the developed one-step multiplex ddPCR assay is cost-effective, highly sensitive and specific, and can simultaneously detect three common respiratory viruses in the complex matrix of wastewater samples even at low concentrations. Due to its high sensitivity and resistance to PCR inhibitors, the developed assay could be further used as an early warning system for wastewater monitoring.


Assuntos
Vírus da Influenza A , Vírus da Influenza B , Reação em Cadeia da Polimerase Multiplex , Águas Residuárias , Águas Residuárias/virologia , Vírus da Influenza A/genética , Vírus da Influenza A/isolamento & purificação , Humanos , Vírus da Influenza B/genética , Vírus da Influenza B/isolamento & purificação , Reação em Cadeia da Polimerase Multiplex/métodos , Sensibilidade e Especificidade , Vírus Sinciciais Respiratórios/genética , Vírus Sinciciais Respiratórios/isolamento & purificação , Reprodutibilidade dos Testes , Influenza Humana/diagnóstico , Influenza Humana/virologia , Influenza Humana/genética , Vírus Sincicial Respiratório Humano/genética , Vírus Sincicial Respiratório Humano/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real/métodos , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação
2.
Molecules ; 29(8)2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38675639

RESUMO

Milk is the most consumed liquid food in the world due to its high nutritional value and relatively low cost, characteristics that make it vulnerable to adulteration. One of the most common types of milk adulteration involves the undeclared addition of cow's milk to milk from other mammalian species, such as goats, sheep, buffalo or donkeys. The incidence of such adulteration not only causes a crisis in terms of commercial market and consumer uncertainty but also poses a risk to public health, as allergies can be triggered by proteins in undeclared cow's milk. In this study, a specific qualitative touchdown (TD) PCR method was developed to detect the undeclared addition of cow's milk in goat and sheep milk based on the discrimination of the peak areas of the melting curves after the modification of bovine-specific primers. The developed methodology has high specificity for the DNA templates of other species, such as buffalos and donkeys, and is able to identify the presence of cow's milk down to 1%. Repeatability was tested at low bovine concentrations of 5% and 1% and resulted in %RSD values of 1.53-2.04 for the goat-cow assay and 2.49-7.16 for the sheep-cow assay, respectively. The application of this method to commercial goat milk samples indicated a high percentage of noncompliance in terms of labeling (50%), while a comparison of the results to rapid immunochromatographic and ELISA kits validated the excellent sensitivity and applicability of the proposed PCR methodology that was able to trace more adulterated samples. The developed assays offer the advantage of multiple detection in a single run, resulting in a cost- and time-efficient method. Future studies will focus on the applicability of these assays in dairy products such as cheese and yogurt.


Assuntos
Contaminação de Alimentos , Cabras , Leite , Reação em Cadeia da Polimerase , Animais , Leite/química , Ovinos , Bovinos , Reação em Cadeia da Polimerase/métodos , Contaminação de Alimentos/análise , Búfalos
3.
Anal Chem ; 95(37): 14068-14076, 2023 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-37681347

RESUMO

Breast cancer is the leading cause of cancer-related deaths in women worldwide. Approximately 40% of patients with hormone receptor-positive, human epidermal growth factor receptor-2-negative breast cancer have activating mutations in the PIK3CA gene. We developed a highly sensitive, specific, cost-effective, and reproducible dual-drop-off droplet digital polymerase chain reaction (PCR) assay for the simultaneous detection of ten hotspots of PIK3CA mutations in plasma cell-free (cf) DNA. We first evaluated the analytical specificity, sensitivity, limit of blank, repeatability, and reproducibility of the assay, which simultaneously detects seven mutations in exon9 and three in exon20. We further applied this assay in 11 gDNA and 18 plasma cfDNA samples from healthy donors and 35 plasma cfDNA samples from metastatic breast cancer patients. The assay is highly sensitive, specific, and applicable for clinical samples containing at least 1-5% mutant DNA. We detected PIK3CA mutations in 9/35(26%) plasma cfDNA samples in exon 9 and in 9/35(26%) in exon 20. Direct comparison of the developed assay with amplification refractory mutation system-based PCR (using plasma samples) and with the Food and Drug Administration-approved cobas PIK3CA mutation assay (using formalin fixed paraffin embedded samples) showed high concordance of our developed assay with the cobas PIK3CA assay. The developed assay is cost-effective and can reliably and simultaneously detect ten hotspot PIK3CA mutations in plasma cfDNA. The clinical performance of the assay will be further evaluated in liquid biopsy samples.


Assuntos
Neoplasias da Mama , Ácidos Nucleicos Livres , Estados Unidos , Humanos , Feminino , Reprodutibilidade dos Testes , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Classe I de Fosfatidilinositol 3-Quinases/genética , Reação em Cadeia da Polimerase
4.
Trends Analyt Chem ; 134: 116125, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33235400

RESUMO

In March 2020 the World Health Organization announced a pandemic outbreak. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative pathogen for the coronavirus disease-19 (COVID-19) pandemic. The authorities worldwide use clinical science to identify infected people, but this approach is not able to track all symptomatic and asymptomatic cases due to limited sampling capacity of the testing laboratories. This drawback is eliminated by the Wastewater-Based Epidemiology (WBE) approach. In this review, we summarized the peer-reviewed published literature (available as of September 28, 2020), in the field of WBE. The commonly used steps (sampling, storage, concentration, isolation, detection) of the analytical protocols were identified. The potential limitations of each stage of the protocols and good practices were discussed. Finally, new methods for the efficient detection of SARS-CoV-2 were proposed.

5.
Horm Metab Res ; 53(7): 461-469, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34282597

RESUMO

Primary aldosteronism (PA) is the most common endocrine cause of arterial hypertension. Despite the increasing incidence of hypertension worldwide, the true prevalence of PA in hypertension was only recently recognized. The objective of the work was to estimate the prevalence of PA in patients at different stages of hypertension based on a newly developed screening-diagnostic overnight test. This is a prospective study with hypertensive patients (n=265) at stage I (n=100), II (n=88), and III (n=77) of hypertension. A group of 103 patients with essential hypertension without PA was used as controls. PA diagnosis was based on a combined screening-diagnostic overnight test, the Dexamethasone-Captopril-Valsartan Test (DCVT) that evaluates aldosterone secretion after pharmaceutical blockade of angiotensin-II and adrenocorticotropic hormone. DCVT was performed in all participants independently of the basal aldosterone to renin ratio (ARR). The calculated upper normal limits for post-DCVT aldosterone levels [3 ng/dl (85 pmol/l)] and post-DCVT ARR [0.32 ng/dl/µU/ml (9 pmol/IU)] from controls, were applied together to establish PA diagnosis. Using these criteria PA was confirmed in 80 of 265 (30%) hypertensives. The prevalence of PA was: 21% (21/100) in stage I, 33% (29/88) in stage II, and 39% (30/77) in stage III. Serum K+ levels were negatively correlated and urinary K+ was positively correlated in PA patients with post-DCVT ARR (r=-0.349, p <0.01, and r=0.27, p <0.05 respectively). In conclusion, DCVT revealed that PA is a highly prevalent cause of hypertension. DCVT could be employed as a diagnostic tool in all subjects with arterial hypertension of unknown cause.


Assuntos
Aldosterona/sangue , Biomarcadores/sangue , Testes Diagnósticos de Rotina/métodos , Hiperaldosteronismo/epidemiologia , Hipertensão/fisiopatologia , Programas de Rastreamento/métodos , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Seguimentos , Grécia/epidemiologia , Humanos , Hiperaldosteronismo/sangue , Hiperaldosteronismo/patologia , Masculino , Pessoa de Meia-Idade , Prevalência , Prognóstico , Estudos Prospectivos , Adulto Jovem
6.
Horm Metab Res ; 52(12): 827-833, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32882712

RESUMO

Primary hyperaldosteronism (PA) is a well-known cause of hypertension although its exact prevalence amongst patients with apparent essential hypertension has been a matter of debate. A number of recent studies have suggested that mild forms of PA may be relatively common taking into consideration factors that were previously either overestimated or ignored when developing diagnostic tests of PA and when applying these tests into normotensive individuals. The performance characteristics and diagnostic accuracy of such tests are substantially increased when the adrenocorticotrophin effect, inappropriate potassium levels and their application in carefully selected normotensive individuals are considered. In the present review, we critically analyze these issues and provide evidence that several, particularly mild, forms of PA can be effectively identified exhibiting potentially important clinical implications.


Assuntos
Aldosterona/sangue , Erros de Diagnóstico/prevenção & controle , Hiperaldosteronismo/diagnóstico , Hipertensão/diagnóstico , Diagnóstico Diferencial , Humanos , Hiperaldosteronismo/sangue , Hiperaldosteronismo/complicações , Hipertensão/sangue , Hipertensão/etiologia
7.
Clin Chem Lab Med ; 58(11): 1799-1807, 2020 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-31953992

RESUMO

Background In metastatic melanoma, 40%-50% of patients harbor a BRAF V600E mutation and are thereby eligible to receive a combined BRAF/MEK inhibitor therapy. Compared to standard-of-care tissue-based genetic testing, analysis of circulating tumor DNA (ctDNA) from blood enables a comprehensive assessment of tumor mutational status in real-time and can be used for monitoring response to therapy. The aim of our study was to directly compare the performance of two highly sensitive methodologies, droplet digital PCR (ddPCR) and a combination of ARMS/asymmetric-rapid PCR/melting curve analysis, for the detection of BRAF V600E in plasma from melanoma patients. Methods Cell-free DNA (cfDNA) was isolated from 120 plasma samples of stage I to IV melanoma patients. Identical plasma-cfDNA samples were subjected to BRAF V600E mutational analysis using in parallel, ddPCR and the combination of ARMS/asymmetric-rapid PCR/melting curve analysis. Results BRAF V600E mutation was detected in 9/117 (7.7%) ctDNA samples by ddPCR and in 22/117 (18.8%) ctDNA samples by the combination of ARMS/asymmetric- rapid PCR/melting curve analysis. The concordance between these two methodologies was 85.5% (100/117). The comparison of plasma-ctDNA analysis using ddPCR and tissue testing revealed an overall agreement of 79.4% (27/34), while the corresponding agreement using the combination of ARMS/asymmetric-rapid PCR/melting curve analysis was 73.5% (25/34). Moreover, comparing the detection of BRAF-mutant ctDNA with the clinics, overall agreement of 87.2% (48/55) for ddPCR and 79.2% (42/53) was demonstrated. Remarkably, the duration of sample storage was negatively correlated with correctness of genotyping results highlighting the importance of pre-analytical factors. Conclusions Our direct comparison study has shown a high level of concordance between ddPCR and the combination of ARMS/asymmetric-rapid PCR/melting curve analysis for the detection of BRAF V600E mutations in plasma.


Assuntos
DNA Tumoral Circulante/sangue , Melanoma/sangue , Proteínas Proto-Oncogênicas B-raf/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Biópsia Líquida , Masculino , Melanoma/genética , Pessoa de Meia-Idade , Mutação , Reação em Cadeia da Polimerase/métodos , Proteínas Proto-Oncogênicas B-raf/genética , Manejo de Espécimes/métodos , Fatores de Tempo
8.
J Musculoskelet Neuronal Interact ; 20(2): 291-296, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32481245

RESUMO

Vitamin D (vitD) deficiency and bone loss may occur after bariatric surgery and hence, supplementation with high oral doses of vitD may be required. Alternatively, intramuscular depot ergocalciferol, which slowly releases vitD and bypasses the gastrointestinal tract, could be administrated. We present a case of severe vitD deficiency-osteomalacia after gastric bypass operation for morbid obesity, treated with ergocalciferol intramuscularly. A 45-year-old woman was presented with hip pain and muscle weakness, which led ultimately to immobilization in a wheelchair. Fifteen years ago, she underwent roux-en-Y gastric by-pass for morbid obesity. Occasionally, she was treated with multivitamin supplements. On admission, iron deficiency anaemia, vitD deficiency (25OHD: 3.7 ng/ml) and secondary hyperparathyroidism were revealed. Bone turnover markers (BTM) were elevated. Radiological evaluation demonstrated insufficiency fractures on the pubic and left femur and reduced BMD. Osteomalacia due to vitD deficiency and calcium malabsorption were diagnosed. Calcium citrate 500 mg qid and intramuscular ergocalciferol 600,000 IU every 20 days were initiated. One month later, musculoskeletal pain and weakness were resolved and the patient was mobilized. Few months later, vitD, BTM and BMD showed substantial improvement. Intramuscular ergocalciferol administration can improve the clinical and biochemical status and thus, is suggested to prevent and/or treat osteomalacia in such patients.


Assuntos
Conservadores da Densidade Óssea/administração & dosagem , Ergocalciferóis/administração & dosagem , Fraturas de Estresse/etiologia , Derivação Gástrica/efeitos adversos , Osteomalacia/tratamento farmacológico , Deficiência de Vitamina D/tratamento farmacológico , Preparações de Ação Retardada/administração & dosagem , Feminino , Humanos , Injeções Intramusculares , Pessoa de Meia-Idade , Obesidade Mórbida/cirurgia , Osteomalacia/etiologia , Deficiência de Vitamina D/etiologia
9.
Anal Chem ; 91(20): 13105-13111, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31538770

RESUMO

Allele-specific polymerase chain reaction (PCR) (amplification-refractory mutation system, ARMS) is one of the most commonly used methods for mutation detection. However, a main limitation of ARMS-PCR is the false positive results obtained due to nonspecific priming that can take place with wild-type (WT) DNA, which often precludes detection of low-level mutations. To improve the analytical specificity of ARMS, we present here a new technology, NAPA: NaME-PrO-assisted ARMS, that overcomes the ARMS deficiency by adding a brief enzymatic step that reduces wild-type alleles just prior to ARMS. We performed this technology for the simultaneous detection of two hot-spot PIK3CA mutations (E545 K and H1047R) in circulating tumor cells (CTCs) and cell free DNA (cfDNA). The developed protocol could simultaneously detect mutation-allelic-frequency of 0.5% for PIK3CA exon 9 (E545 K) and 0.1% for PIK3CA exon 20 (H1047R) with high specificity. We further compared the developed NAPA assay with (a) ddPCR considered as the gold standard and (b) our previous assay based on the combination of allele-specific, asymmetric rapid PCR, and melting analysis. Our data show that the newly developed NAPA assay gives consistent results with both these assays (p = 0.001). The developed assay resolves the false positive signals issue derived through classic ARMS-PCR and provides an ideal combination of speed, accuracy, and versatility and should be easily applicable in routine diagnostic laboratories.


Assuntos
Classe I de Fosfatidilinositol 3-Quinases/análise , Biópsia Líquida , Reação em Cadeia da Polimerase/métodos , Alelos , Neoplasias da Mama/sangue , Linhagem Celular Tumoral , DNA Tumoral Circulante/análise , DNA Tumoral Circulante/genética , Classe I de Fosfatidilinositol 3-Quinases/genética , Sondas de DNA/química , Endodesoxirribonucleases/química , Feminino , Humanos , Mutação , Células Neoplásicas Circulantes
10.
Anal Chem ; 91(5): 3443-3451, 2019 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-30663875

RESUMO

Liquid biopsy, based on the molecular information extracted from circulating tumor cells (CTCs) and circulating tumor DNA (ctDNA), offers the possibility to characterize the evolution of a solid tumor in real time and is highly important for diagnostic and therapeutic purposes. The aim of the present study was the development and validation of a novel liquid bead array methodology for the molecular characterization of CTCs and its application in breast cancer. In the present study we developed and evaluated a multiplex polymerase chain reaction (PCR)-coupled liquid bead array (MLBA) assay for studying simultaneously the expression of 14 genes in CTCs. The 14-gene MLBA assay is characterized by high analytical specificity, sensitivity, and reproducibility. The analytical performance of the 14-gene MLBA assay was compared with a commercially available test (AdnaTest BreastCancer, Qiagen, Germany) and our previously described multiplex quantitative reverse transcription PCR (RT-qPCR) assays. The developed assay has the potential to be further expanded in order to include up to 100 gene targets. The assay is highly specific for each target gene and is not affected by the numerous primers and probes used for multiplexing; hence, it constitutes a sample-, cost-, and time-saving analysis.


Assuntos
Biomarcadores Tumorais/genética , DNA de Neoplasias/genética , Reação em Cadeia da Polimerase Multiplex , Células Neoplásicas Circulantes/patologia , Análise de Sequência com Séries de Oligonucleotídeos , Linhagem Celular Tumoral , Humanos
11.
Clin Chem ; 64(2): 297-306, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29122836

RESUMO

BACKGROUND: Molecular characterization of circulating tumor cells (CTCs) is important for selecting patients for targeted treatments. We present, for the first time, results on gene expression profiling of CTCs isolated in vivo from high-risk prostate cancer (PCa) patients compared with CTC detected by 3 protein-based assays-CellSearch®, PSA-EPISPOT, and immunofluorescence of CellCollector® in vivo-captured CTCs-using the same blood draw. METHODS: EpCAM-positive CTCs were isolated in vivo using the CellCollector from 108 high-risk PCa patients and 36 healthy volunteers. For 27 patients, samples were available before and after treatment. We developed highly sensitive multiplex RT-qPCR assays for 14 genes (KRT19, EpCAM, CDH1, HMBS, PSCA, ALDH1A1, PROM1, HPRT1, TWIST1, VIM, CDH2, B2M, PLS3, and PSA), including epithelial markers, stem cell markers, and epithelial-to-mesenchymal-transition (EMT) markers. RESULTS: We observed high heterogeneity in gene expression in the captured CTCs for each patient. At least 1 marker was detected in 74 of 105 patients (70.5%), 2 markers in 45 of 105 (40.9%), and 3 markers in 16 of 105 (15.2%). Epithelial markers were detected in 31 of 105 (29.5%) patients, EMT markers in 46 of 105 (43.8%), and stem cell markers in 15 of 105 (14.3%) patients. EMT-marker positivity was very low before therapy (2 of 27, 7.4%), but it increased after therapy (17 of 27, 63.0%), whereas epithelial markers tended to decrease after therapy (2 of 27, 7.4%) compared with before therapy (13 of 27, 48.1%). At least 2 markers were expressed in 40.9% of patients, whereas the positivity was 19.6% for CellSearch, 38.1% for EPISPOT, and 43.8% for CellCollector-based IF-staining. CONCLUSIONS: The combination of in vivo CTC isolation with downstream RNA analysis is highly promising as a high-throughput, specific, and ultrasensitive approach for multiplex liquid biopsy-based molecular diagnostics.


Assuntos
Perfilação da Expressão Gênica/métodos , Reação em Cadeia da Polimerase Multiplex/métodos , Células Neoplásicas Circulantes/metabolismo , Neoplasias da Próstata/sangue , Neoplasias da Próstata/genética , Estudos de Casos e Controles , Ensaio de Imunoadsorção Enzimática/métodos , Molécula de Adesão da Célula Epitelial/sangue , Transição Epitelial-Mesenquimal/genética , Imunofluorescência/métodos , Heterogeneidade Genética , Humanos , Masculino , Antígeno Prostático Específico/sangue , Sensibilidade e Especificidade
12.
Addict Biol ; 23(1): 206-218, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28224681

RESUMO

Different methamphetamine use patterns in human subjects may contribute to inconsistent findings regarding the effects of methamphetamine abuse on brain and behavior. The present study investigated whether human-derived chronic and binge methamphetamine use patterns have differential effects on reward and neurochemistry in mice. Brain reward function in mice was evaluated during acute/prolonged withdrawal, and in response to methamphetamine challenge using the intracranial self-stimulation procedure. Brain dopaminergic, serotonergic and glutamatergic neurochemistry was determined with high-performance liquid chromatography. Chronic and binge regimens induced withdrawal-related decreases in reward function that were more severe during the binge regimen during cycles 1-2. Despite large differences in methamphetamine dose, both regimens induced similar reward deficits during cycles 3-4. Neither methamphetamine regimen led to persistent alterations in the sensitivity to the reward-enhancing effects of acute methamphetamine challenge. The binge regimen severely depleted striatal dopamine levels and increased brain glutamine levels. The chronic regimen had milder effects on striatal dopamine levels and altered cortical dopamine and serotonin levels. This work highlights that the magnitude of acute/prolonged withdrawal may not reflect amount or frequency of methamphetamine intake. In contrast, the array of underlying neurochemical alterations was methamphetamine regimen dependent. Thus, stratifying methamphetamine-dependent individuals based on use pattern may help to cater therapeutic interventions more appropriately by targeting use pattern-specific neurotransmitter systems.


Assuntos
Transtornos Relacionados ao Uso de Anfetaminas/metabolismo , Encéfalo/metabolismo , Estimulantes do Sistema Nervoso Central/administração & dosagem , Dopamina/metabolismo , Glutamina/metabolismo , Metanfetamina/administração & dosagem , Serotonina/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Estimulantes do Sistema Nervoso Central/farmacologia , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Modelos Animais de Doenças , Glutamina/efeitos dos fármacos , Metanfetamina/farmacologia , Camundongos , Recompensa , Autoestimulação
13.
Addict Biol ; 23(1): 111-119, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-27894160

RESUMO

Exposure to smoking-associated environmental cues during smoke cessation elicits self-reported urge/craving to smoke, which precipitates relapse even after prolonged abstinence. Incubation of cue-induced cigarettes craving during abstinence has been observed in human smokers recently. The present studies assessed cue-induced nicotine-seeking behavior under different withdrawal conditions in rats with a history of nicotine self-administration. We found that non-reinforced operant responding during cue-induced nicotine seeking after different periods of withdrawal from nicotine exhibited an inverted U-shaped curve, with higher levels of responding after 7-21 days of withdrawal than those after 1-day withdrawal. Cue-induced nicotine-seeking responding is long lasting and persists even after 42 days of forced withdrawal in the home cages. Interestingly, repeated testing of cue-induced nicotine seeking at different withdrawal time points (1, 7, 14, 21 and 42 days) in the same individual alleviated responding as compared with the between-subjects assessment. Furthermore, extinction training during nicotine withdrawal significantly decreased cue-induced reinstatement of nicotine-seeking behavior. Together, profound time-dependent incubation of cue-induced craving in nicotine-experienced rats were observed. In addition, repeated cue exposure or extinction training decreases cue-induced craving. The demonstration of incubation of nicotine craving phenomenon in both rat and human studies provides support for the translational potential of therapeutic targets for relapse uncovered through mechanism studies in rats.


Assuntos
Sinais (Psicologia) , Comportamento de Procura de Droga , Nicotina , Agonistas Nicotínicos , Animais , Comportamento Animal , Condicionamento Operante , Fissura , Extinção Psicológica , Masculino , Ratos , Autoadministração , Fatores de Tempo
14.
Clin Endocrinol (Oxf) ; 86(4): 488-498, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27992961

RESUMO

OBJECTIVE: Adrenal incidentalomas (AI) are associated with metabolic and hormonal abnormalities, most commonly autonomous cortisol secretion (ACS). Data regarding alterations of insulin resistance (IR) and ACS after prolonged follow-up are limited. We investigated the evolution of IR, cortisol secretion and ACS development in patients with AI during prolonged follow-up. DESIGN: Prospective study in a tertiary hospital. PATIENTS AND MEASUREMENTS: Seventy-one patients with AI [51 nonfunctioning (NFAI) and 20 ACS] and 5·54 ± 1·7 years follow-up underwent testing for ACS and oral glucose tolerance test to determine IR indices and adrenal imaging. RESULTS: At follow-up, 16/51 (31%) NFAI patients converted to ACS, while two with previous ACS reverted to NFAI; 21% (7/33) of patients who did not covert to ACS exhibited high urinary-free cortisol (H-UFC) levels. All AI patients developed deterioration of IR irrespective of their cortisol secretory status. Eight patients developed newly diagnosed type 2 diabetes (9·8% NFAI and 15% ACS, respectively) and 14 IR (17·6% NFAI and 25% ACS, respectively). Adenoma size increased from 2·1 ± 0·8 to 2·3 ± 0·8 cm, whereas IR correlated with postdexamethasone cortisol level and adenoma size increase. IR showed an incremental continuum trend from normal UFC (Ν-UFC), to H-UFC, C-ACS and ACS patients. CONCLUSIONS: New-onset ACS developed in 31% patients with NFAI, whereas 21% of NFAI patients had H-UFC levels. All AI patients as a group and the subgroups of N-UFC, H-UFC, C-ACS and ACS patients developed deterioration of metabolic parameters during follow-up that was more prominent in ACS patients.


Assuntos
Neoplasias das Glândulas Suprarrenais/metabolismo , Doenças Cardiovasculares/etiologia , Hidrocortisona/metabolismo , Neoplasias das Glândulas Suprarrenais/complicações , Idoso , Doenças Cardiovasculares/diagnóstico , Diabetes Mellitus Tipo 2 , Progressão da Doença , Feminino , Seguimentos , Humanos , Resistência à Insulina , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco
15.
Clin Chem ; 62(7): 1002-11, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27197674

RESUMO

BACKGROUND: Circulating tumor cells (CTCs) and microRNAs (miRNAs) are important in liquid biopsies in which peripheral blood is used to characterize the evolution of solid tumors. We evaluated the expression levels of miR-21, miR-146a, miR-200c, and miR-210 in CTCs of breast cancer patients with verified metastasis and compared their expression levels in corresponding plasma and primary tumors. METHODS: Expression levels of the miRNAs were quantified by quantitative reverse transcription PCR (RT-qPCR) in (a) 89 primary breast tumors and 30 noncancerous breast tissues and (b) CTCs and corresponding plasma of 55 patients with metastatic breast cancer and 20 healthy donors. For 30 of these patients, CTCs, corresponding plasma, and primary tumor tissues were available. RESULTS: In formalin-fixed, paraffin-embedded tissues, these miRNAs were differentially expressed between primary breast tumors and noncancerous breast tissues. miR-21 (P < 0.001) and miR-146a (P = 0.001) were overexpressed, whereas miR-200c (P = 0.004) and miR-210 (P = 0.002) were underexpressed. In multivariate analysis, miR-146a overexpression was significantly [hazard ratio 2.969 (1.231-7.157), P = 0.015] associated with progression-free survival. In peripheral blood, all miRNAs studied were overexpressed in both CTC and corresponding plasma. There was a significant association between miR-21 expression levels in CTCs and plasma for 36 of 55 samples (P = 0.008). In plasma, ROC curve analysis revealed that miR-21, miR-146a, and miR-210 could discriminate patients from healthy individuals. CONCLUSIONS: Metastasis-related miRNAs are overexpressed in CTCs and corresponding plasma; miR-21 expression levels highly correlate in CTCs and plasma; and miR-21, miR-146a, and miR-210 are valuable plasma biomarkers for discriminating patients from healthy individuals.


Assuntos
Neoplasias da Mama/sangue , Neoplasias da Mama/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/sangue , MicroRNAs/genética , Células Neoplásicas Circulantes/metabolismo , Células Neoplásicas Circulantes/patologia , Neoplasias da Mama/patologia , Feminino , Perfilação da Expressão Gênica , Humanos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
16.
Clin Endocrinol (Oxf) ; 85(6): 845-851, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27293068

RESUMO

BACKGROUND: Germline mutations of the KCNJ5 gene encoding Kir3·4, a member of the inwardly rectifying K+ channel, have been identified in 'normal' adrenal glands, patients with familial hyperaldosteronism (FH) type III, aldosterone-producing adenomas (APAs) and sporadic cases of primary aldosteronism (PA). OBJECTIVE: To present two novel KCNJ5 gene mutations in hypertensive patients without PA, but with Adrenocorticotropic hormone (ACTH)-dependent aldosterone hypersecretion. DESIGN AND PATIENTS: Two hypertensive patients without PA, who exhibited enhanced ACTH-dependent response of aldosterone secretion, underwent genetic testing for the presence of the CYP11B1/CYP11B2 chimeric gene and KCNJ5 gene mutations. Genomic DNA was isolated from peripheral white blood cells, and the exons of the entire coding regions of the above genes were amplified and sequenced. Electrophysiological studies were performed to determine the effect of identified mutation(s) on the membrane reversal potentials. Structural biology studies were also carried out. RESULTS: Two novel germline heterozygous KCNJ5 mutations, p.V259M and p.Y348N, were detected in the two subjects. Electrophysiological studies showed that the Y348N mutation resulted in significantly less negative reversal potentials, suggesting loss of ion selectivity, while the V259M mutation did not affect the Kir3.4 current. In the mutated structural biology model, the N348 mutant resulted in significant loss of the ability for hydrogen bonding, while the M259 mutant was capable of establishing weaker interactions. The CYP11B1/CYP11B2 chimeric gene was not detected. CONCLUSIONS: These findings expand on the clinical spectrum of phenotypes associated with KCNJ5 mutations and implicate these mutations in the pathogenesis of hypertension associated with increased aldosterone response to ACTH stimulation.


Assuntos
Hormônio Adrenocorticotrópico/farmacologia , Aldosterona/metabolismo , Canais de Potássio Corretores do Fluxo de Internalização Acoplados a Proteínas G/genética , Mutação em Linhagem Germinativa/fisiologia , Hipertensão/etiologia , Citocromo P-450 CYP11B2/genética , Fenômenos Eletrofisiológicos , Feminino , Estudos de Associação Genética , Humanos , Hiperaldosteronismo , Masculino , Pessoa de Meia-Idade , Esteroide 11-beta-Hidroxilase/genética
17.
Addict Biol ; 21(4): 826-34, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-25950618

RESUMO

Many adolescents engage in heavy alcohol use. Limited research in humans indicates that adolescent alcohol use predicts adult tobacco use. The present study investigated whether adolescent intermittent ethanol (AIE) exposure alters nicotine sensitivity in adulthood. Adolescent male Wistar rats (postnatal day 28-53) were exposed to AIE exposure that consisted of 5 g/kg of 25 percent ethanol three times per day in a 2 days on/2 days off regimen. Control rats received water with the same exposure regimen. In adulthood, separate groups of rats were tested for nicotine intravenous self-administration (IVSA), drug discrimination and conditioned taste aversion (CTA). The dose-response function for nicotine IVSA under a fixed-ratio schedule of reinforcement was similar in AIE-exposed and control rats. However, AIE-exposed rats self-administered less nicotine at the lowest dose, suggesting that low-dose nicotine was less reinforcing in AIE-exposed, compared with control rats. AIE-exposed rats self-administered less nicotine under a progressive-ratio schedule, suggesting decreased motivation for nicotine after AIE exposure. The discriminative stimulus effects of nicotine were diminished in AIE-exposed rats compared with control rats. No group differences in nicotine CTA were observed, suggesting that AIE exposure had no effect on the aversive properties of nicotine. Altogether, these results demonstrate that AIE exposure decreases sensitivity to the reinforcing, motivational and discriminative properties of nicotine while leaving the aversive properties of nicotine unaltered in adult rats. These findings suggest that drinking during adolescence may result in decreased sensitivity to nicotine in adult humans, which may in turn contribute to the higher rates of tobacco smoking.


Assuntos
Depressores do Sistema Nervoso Central/farmacologia , Etanol/farmacologia , Nicotina/farmacologia , Consumo de Bebidas Alcoólicas , Animais , Condicionamento Clássico/efeitos dos fármacos , Modelos Animais de Doenças , Masculino , Ratos , Ratos Wistar
19.
Adv Exp Med Biol ; 867: 341-67, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26530376

RESUMO

Detection of Circulating Tumor Cells (CTCs) in peripheral blood can serve as a "liquid biopsy" approach and as a source of valuable tumor markers. CTCs are rare, and thus their detection, enumeration and molecular characterization are very challenging. CTCs have the unique characteristic to be non-invasively isolated from blood and used to follow patients over time, since these cells can provide significant information for better understanding tumour biology and tumour cell dissemination. CTCs molecular characterization offers the unique potential to understand better the biology of metastasis and resistance to established therapies and their analysis presents nowadays a promising field for both advanced and early stage patients. In this chapter we focus on the latest findings concerning the clinical relevance of CTC detection and enumeration, and discuss their potential as tumor biomarkers in various types of solid cancers. We also highlight the importance of performing comparison studies between these different methodologies and external quality control systems for establishing CTCs as tumor biomarkers in the routine clinical setting.


Assuntos
Biomarcadores Tumorais , Neoplasias/diagnóstico , Células Neoplásicas Circulantes , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/patologia , Feminino , Humanos , Neoplasias Pulmonares/diagnóstico , Masculino , Neoplasias da Próstata/diagnóstico
20.
Crit Rev Clin Lab Sci ; 51(3): 160-71, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24641350

RESUMO

The presence of circulating tumor cells (CTCs) in peripheral blood can serve as a "liquid biopsy" approach and has thus emerged lately as one of the hottest fields in cancer research. CTCs can be isolated from blood in a non-invasive approach, and can be used to follow patients over time since these cells can provide significant information for a better understanding of tumor biology and tumor cell dissemination. CTC molecular characterization offers the unique potential to better understand the biology of metastasis and resistance to established therapies, and analysis of these cells presents a promising field for both advanced and early-stage patients. CTC detection, enumeration, and molecular characterization are very challenging since CTCs are rare, and the amount of available sample is very limited. Since detection of CTCs has been shown to be of considerable utility in the clinical management of patients with solid cancers, various analytical systems for their isolation and detection have been developed. New areas of research are directed towards developing novel assays for single-CTC isolation and molecular characterization. The clinical significance of CTCs has been evaluated in many types of solid cancers, and the CTC enumeration test in metastatic breast, colorectal, and prostate cancer was cleared by the FDA almost a decade ago. This review is mainly focused on the clinical potential of CTCs as novel biomarkers in 10 different types of solid cancers: breast, ovarian, prostate, lung, colorectal, hepatocellular carcinoma, pancreatic, head and neck, bladder cancer and melanoma.


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias/sangue , Neoplasias/patologia , Células Neoplásicas Circulantes/patologia , Humanos , Neoplasias/diagnóstico
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