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1.
Sci Rep ; 11(1): 9833, 2021 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-33986305

RESUMO

The equatorial tropics house some of the earliest rock art yet known, and it is weathering at an alarming rate. Here we present evidence for haloclasty (salt crystallisation) from Pleistocene-aged rock art panels at 11 sites in the Maros-Pangkep limestone karsts of southern Sulawesi. We show how quickly rock art panels have degraded in recent decades, contending that climate-catalysed salt efflorescence is responsible for increasing exfoliation of the limestone cave surfaces that house the ~ 45 to 20-thousand-year-old paintings. These artworks are located in the world's most atmospherically dynamic region, the Australasian monsoon domain. The rising frequency and severity of El Niño-induced droughts from anthropogenic climate change (that is, higher ambient temperatures and more consecutive dry days), combined with seasonal moisture injected via monsoonal rains retained as standing water in the rice fields and aquaculture ponds of the region, increasingly provide ideal conditions for evaporation and haloclasty, accelerating rock art deterioration.

2.
Asian Pac J Cancer Prev ; 19(9): 2561-2568, 2018 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-30256056

RESUMO

Background/objective: HCC is a multistep process starting from chronic hepatitis that progress through cirrhosis to HCC. MicroRNA expression level was found to be deregulated in HCC. To find out whether the expression level of miR-34a and miR-183 was deregulated in HCC compared to controls without HCC. Methods: Real time quantitative PCR was done to find out the miRNA expression level in terms of Ct value followed by statistical analysis. Results: Over-expression of miR-183 and under-expression of miR-34a in HCC was detected. All changes in expression level of miR-34a and miR-183 were found to be due to HCC compared to controls without HCC. So both miR-34a and miR-183 were suitable to differentiate HCC from Cirrhosis and chronic hepatitis with an efficient diagnostic power of sensitivity, specificity and expression level. But they might not have any role in patients' survival. Conclusion: miR- 34a and miR-183 might be considered as potential markers of HCC screening molecule in addition to other approved panel of marker. Our study warrants further expression level study.


Assuntos
Biomarcadores Tumorais/sangue , Carcinoma Hepatocelular/sangue , Neoplasias Hepáticas/sangue , MicroRNAs/sangue , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Estudos de Casos e Controles , Feminino , Seguimentos , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Prognóstico , Taxa de Sobrevida
3.
Ann Clin Biochem ; 55(1): 69-76, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28661203

RESUMO

Background The National Institute for Health and Care Excellence (NICE) published NG12 in 2015. The referral criteria for suspected colorectal cancer (CRC) caused controversy, because tests for occult blood in faeces were recommended. Faecal immunochemical tests for haemoglobin (FIT), which estimate faecal haemoglobin concentrations (f-Hb), might more than fulfil the intentions. Our aim was to compare the utility of f-Hb as the initial investigation with the NICE NG12 symptom-based guidelines. Methods Data from three studies were included. Patients had sex, age, symptoms, f-Hb and colonoscopy and histology data recorded. Sensitivity, specificity, positive (PPV) and negative predictive value (NPV) of f-Hb and NG12 were calculated for all significant colorectal disease (SCD: CRC, higher risk adenoma and inflammatory bowel disease). Overall diagnostic accuracy was also estimated by the area under the receiver operating characteristic curve (AUC). Results A total of 1514 patients were included. At a cut-off of ≥10 µg Hb/g faeces, the sensitivity of f-Hb for CRC was 93.3% (95% confidence interval (CI): 80.7-98.3) with NPV of 99.7% (95%CI: 99.2-99.9). The sensitivity and NPV for SCD were 63.2% (95%CI: 56.6-69.4) and 96.0% (95%CI: 91.4-94.4), respectively. The NG12 sensitivity and NPV for SCD were 58.4% (95%CI: 51.8-64.8) and 87.6% (95%CI: 85.0-89.8), respectively. The AUC for CRC was 0.85 (95% CI: 0.87-0.90) for f-Hb versus 0.65 (95%CI: 0.58-0.73) for NG12 ( P < 0.005). For SCD, the AUC was 0.73 (95%CI: 0.69-0.77) for f-Hb versus 0.56 (95%CI: 0.52-0.60) for NG12 ( P < 0.0005). Conclusion f-Hb provides a good rule-out test for SCD and has significantly higher overall diagnostic accuracy than NG12.


Assuntos
Colo/fisiopatologia , Doenças do Colo/diagnóstico , Guias de Prática Clínica como Assunto , Doenças Retais/diagnóstico , Reto/fisiopatologia , Doenças do Colo/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Retais/fisiopatologia , Sensibilidade e Especificidade
4.
Nature ; 514(7521): 223-7, 2014 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-25297435

RESUMO

Archaeologists have long been puzzled by the appearance in Europe ∼40-35 thousand years (kyr) ago of a rich corpus of sophisticated artworks, including parietal art (that is, paintings, drawings and engravings on immobile rock surfaces) and portable art (for example, carved figurines), and the absence or scarcity of equivalent, well-dated evidence elsewhere, especially along early human migration routes in South Asia and the Far East, including Wallacea and Australia, where modern humans (Homo sapiens) were established by 50 kyr ago. Here, using uranium-series dating of coralloid speleothems directly associated with 12 human hand stencils and two figurative animal depictions from seven cave sites in the Maros karsts of Sulawesi, we show that rock art traditions on this Indonesian island are at least compatible in age with the oldest European art. The earliest dated image from Maros, with a minimum age of 39.9 kyr, is now the oldest known hand stencil in the world. In addition, a painting of a babirusa ('pig-deer') made at least 35.4 kyr ago is among the earliest dated figurative depictions worldwide, if not the earliest one. Among the implications, it can now be demonstrated that humans were producing rock art by ∼40 kyr ago at opposite ends of the Pleistocene Eurasian world.


Assuntos
Arte/história , Cavernas , Animais , Cervos , História Antiga , Atividades Humanas/história , Indonésia , Suínos , Urânio
5.
Rheumatology (Oxford) ; 48(11): 1447-50, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19748963

RESUMO

OBJECTIVE: The present study was conducted to improve our knowledge of intervertebral disc (IVD) cell biology by comparing the phenotype of nucleus pulposus (NP) and annulus fibrosus (AF) cells with that of articular chondrocytes (ACs). METHODS: Rabbit cells from NP and AF were isolated and their phenotype was compared with that of AC by real-time PCR analysis of type I (COL1A1), II (COL2A1) and V (COL5A1) collagens, aggrecan transcript (AGC1), matrix Gla protein (MGP) and Htra serine peptidase 1 (Htra1). RESULTS: Transcript analysis indicated that despite certain similarities, IVD cells exhibit distinct COL2A1/COL1A1 and COL2A1/AGC1 ratios as compared with AC. The expression pattern of COL5A1, MGP and Htra1 makes it possible to define a phenotypic signature for NP and AF cells. CONCLUSIONS: Our study shows that NP and AF cells exhibit a clearly distinguishable phenotype from that of AC. Type V collagen, MGP and HtrA1 could greatly help to discriminate among NP, AF and AC cells.


Assuntos
Cartilagem Articular/citologia , Condrócitos/citologia , Disco Intervertebral/citologia , Animais , Biomarcadores/metabolismo , Cartilagem Articular/metabolismo , Condrócitos/metabolismo , Proteínas da Matriz Extracelular/biossíntese , Proteínas da Matriz Extracelular/genética , Disco Intervertebral/metabolismo , Fenótipo , Coelhos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos
6.
Meas Sci Technol ; 20(4)2009 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-29520129

RESUMO

Specific absorption rate (SAR) measurements require accurate calculations of the dielectric properties of tissue-equivalent liquids and associated calibration of E-field probes. We developed a precise tissue-equivalent dielectric measurement and E-field probe calibration system. The system consists of a rectangular waveguide, electric field probe, and data control and acquisition system. Dielectric properties are calculated using the field attenuation factor inside the tissue-equivalent liquid and power reflectance inside the waveguide at the air/dielectric-slab interface. Calibration factors were calculated using isotropicity measurements of the E-field probe. The frequencies used are 900 MHz and 1800 MHz. The uncertainties of the measured values are within ±3%, at the 95% confidence level. Using the same waveguide for dielectric measurements as well as calibrating E-field probes used in SAR assessments eliminates a source of uncertainty. Moreover, we clearly identified the system parameters that affect the overall uncertainty of the measurement system.

7.
Rapid Commun Mass Spectrom ; 17(2): 122-5, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12512090

RESUMO

The mechanism of attachment of Na(+) on glucose, methyl-alpha-D-glucose, methyl-beta-D-glucose, 3-O-methylglucose, tetra-O-methylglucose, and also on galactose and methyl-beta-D-galactose, was studied. For this we measured the ion yields for the complex [sugar-Na(+)] formed by ionisation by matrix-assisted laser desorption/ionisation (MALDI) and ionspray. These data were compared with the relative volatilities and hydrophobicities of the sugars, measured by evaporative light scattering and reversed-phase liquid chromatography, respectively. Some formation enthalpies for the complexes [sugar-Na(+)], starting from the sugar and the cation, were obtained by ab initio calculations. No simple correlations could be observed between the ion yields and the parameters studied, so that the cationisation mechanism of the sugars remains unclear.


Assuntos
Glucose/química , Metilglucosídeos/química , Sódio/química , Temperatura Alta , Interações Hidrofóbicas e Hidrofílicas , Metilação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Volatilização
8.
Rapid Commun Mass Spectrom ; 15(4): 273-6, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11223958

RESUMO

In matrix-assisted laser desorption/ionization mass spectrometry, carbohydrates ionize by attachment of an alkali cation, and the ion yield varies with the nature of the cation. In an attempt to contribute to the understanding of the mechanisms involved, we have conducted matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) experiments on the simple glucose molecule with the alkali cations Li+, Na+ and K+, and have also performed ab initio calculations. The calculations show that, for the most stable carbohydrate-cation geometry, the carbohydrate ring is twisted and the cation is coordinated to four oxygen atoms. Calculations also show that in these complexes the positions of the three cations are very similar, and the smaller the cation, the closer it is to the oxygen atoms. Finally, the calculated formation enthalpies of the different complexes agree with the experimental results obtained for the order of stability of these complexes.


Assuntos
Cátions Monovalentes/química , Glucose/química , Configuração de Carboidratos , Lítio/química , Modelos Moleculares , Potássio/química , Sódio/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos
9.
Rapid Commun Mass Spectrom ; 14(2): 68-70, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10623931

RESUMO

Mixtures of methylated beta-cyclodextrins were characterized using three different methods of mass spectrometry: ionspray, atmospheric pressure chemical ionization (APCI) and matrix-assisted laser desorption/ionization (MALDI). Each of these methods allows a fast and simple determination of the degree of substitution, and can provide evidence for differences in the methylation of batches which have very similar global degrees of substitution. The three methods are in good qualitative agreement, but there are systematic differences in the quantitative results for the percentages of the various methylated molecules present in a batch. This is attributed to ionization yields which increase with the number of methyl groups, with different slopes for the different methods.


Assuntos
Ciclodextrinas/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , beta-Ciclodextrinas , Pressão Atmosférica , Metilação
10.
Rapid Commun Mass Spectrom ; 13(23): 2302-2304, 1999 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-10567927

RESUMO

Aspects of direct laser desorption/ionisation have been studied for three molecules, aminotriazole (positive ion), dinoterb and ioxynil (negative ion). The samples are deposited on metallic substrates, and a nitrogen laser is used for desorption/ionisation; ion yields are measured with a time-of-flight mass spectrometer. Previous work had shown that ion yields can strongly vary from one substrate to another, and that this variation does not reflect the (calculated) metal surface temperatures. New results obtained in this work indicate that the desorption/ionisation mechanism is linked to the physical state of the substrate surface. Copyright 1999 John Wiley & Sons, Ltd.

11.
J Clin Gastroenterol ; 19(2): 135-8, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7963361

RESUMO

We present a case of necrotizing lymphomatous colitis--masquerading as Crohn's disease--that was complicated by spontaneous multiple perforations. This potentially fatal occurrence might have been obviated by earlier immunologic diagnosis.


Assuntos
Colite/etiologia , Neoplasias do Colo/complicações , Neoplasias do Colo/diagnóstico , Doença de Crohn/diagnóstico , Linfoma Difuso de Grandes Células B/complicações , Linfoma Difuso de Grandes Células B/diagnóstico , Colite/patologia , Colo/patologia , Neoplasias do Colo/patologia , Feminino , Humanos , Linfoma Difuso de Grandes Células B/patologia , Pessoa de Meia-Idade , Necrose
12.
Gastroenterology ; 99(4): 909-17, 1990 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2168329

RESUMO

The development of esophagitis is the result of hydrogen ion diffusion into the mucosa leading to cellular acidification and necrosis. In these studies, whether esophageal cells possess transport system(s) that can respond to cytoplasmic acidification was assessed; specifically, whether esophageal cells possess an Na+,H+ antiport was determined. Nucleated esophageal cells were isolated from rabbit esophagi using a trypsin-digestion technique that yielded 5-8 x 10(6) cells per esophagus, of which 74% +/- 3% were basal and 26% +/- 8% were squamous. Trypan blue was excluded by 95% +/- 2% of the cells. Cytoplasmic pH (pHi) was measured using the pH-sensitive fluorescence dye 2',7'-bis(2-carboxyethyl)-5 (and -6) carboxyfluorescein acetoxymethyl ester. Cells were acidified to the desired pHi by suspension in solutions with varying external pH (pHo) in the presence of nigericin. When cells acidified to pHi 6.3 were suspended in a choline chloride solution (pHo 7.4), cytoplasmic pHi did not increase. In contrast, Nao+ caused a concentration-dependent increase in the rate of cytoplasmic alkalinization with saturation occurring above 50 mmol/L Nao+. The transporter behaved according to first-order Michaelis-Menten type kinetics with respect to external Na+ and had an apparent Km for Nao+ of 38.4 mmol/L. In contrast, the transporter behaved with greater than first-order kinetics with respect to external Na+ and had an apparent Km for Nao+ of 38.4 mmol/L. In contrast, the transporter behaved with greater than first-order kinetics with respect to cytoplasmic hydrogen ion concentration. Amiloride (10(-4) mol/L) caused a reversible inhibition of Na(+)-dependent alkalinization. Amiloride-sensitive cytoplasmic alkalinization was not observed when either cholineo or Ko+ was substituted for Nao+, while Lio+ resulted in alkalinization that was 60% +/- 8% of that seen with equimolar concentrations of Nao+. The basal pHi of cells suspended in a bicarbonate-free 130 mmol/L NaCl solution (pHo 7.4) averaged 7.42 +/- 0.03 (n = 10); amiloride (10(-4) mmol/L caused the basal pHi to decrease to 7.26 +/- 0.05 (n = 10; P less than 0.0025). When cells were suspended in a choline chloride (pHo 7.4) solution, pHi averaged 7.29 +/- 0.06 (n = 10) (P less than 0.0025 compared with Nao+). These studies indicate that nucleated esophageal cells obtained from rabbits possess an amiloride-sensitive Na+,H+ antiport that functions to regulate basal pHi and responds to intracellular acidification.


Assuntos
Proteínas de Transporte/metabolismo , Esôfago/metabolismo , Amilorida/farmacologia , Animais , Proteínas de Transporte/efeitos dos fármacos , Células Cultivadas , Esofagite Péptica/metabolismo , Esôfago/citologia , Concentração de Íons de Hidrogênio , Masculino , Coelhos , Trocadores de Sódio-Hidrogênio
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