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1.
Soft Matter ; 18(42): 8124-8133, 2022 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-36239275

RESUMEN

The displacement of a suspension of particles by an immiscible fluid in a capillary tube or in porous media is a canonical configuration that finds application in a large number of natural and industrial applications, including water purification, dispersion of colloids and microplastics, coating and functionalization of tubings. The influence of particles dispersed in the fluid on the interfacial dynamics and on the properties of the liquid film left behind remain poorly understood. Here, we study the deposition of a coating film on the walls of a capillary tube induced by the translation of a suspension plug pushed by air. We identify the different deposition regimes as a function of the translation speed of the plug, the particle size, and the volume fraction of the suspension. The thickness of the coating film is characterized, and we show that similarly to dip coating, three coating regimes are observed, liquid only, heterogeneous, and thick films. We also show that, at first order, the thickness of films thicker than the particle diameter can be predicted using the effective viscosity of the suspension. Nevertheless, we also report that for large particles and concentrated suspensions, a shear-induced migration mechanism leads to local variations in volume fraction and modifies the deposited film thickness and composition.

3.
Reprod Domest Anim ; 50(1): 149-58, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25522189

RESUMEN

This study evaluated the structural changes in the reproductive tract of Asiatic black bears using serial transrectal ultrasonography. In addition, the ultrasonographic observations were compared with the results of vaginal cytology and hormonal analyses. The collection of blood for hormonal analysis, vaginal cytology and transrectal ultrasonography was performed in two bears (Bears 1 and 2) from June 2011 to August 2013 without mating and in a third bear (Bear 3) from April to December 2012, allowing natural mating. Serial ultrasonographic observations showed cyclic changes in ovarian structures (e.g. emergence of small follicles, growth and ovulation of dominant follicles and corpus luteum (CL) formation) during the reproductive cycles of the three bears. The diameter of the uterine horns remained similar throughout the reproductive cycle in Bears 1 and 2, and it remained similar from April until October, but an enlargement containing foetuses was observed in Bear 3 in December. The ultrasonographic observations were consistent with the data obtained through vaginal cytology and progesterone analysis during the reproductive cycle. An average of 4.0 (±0.4) dominant follicles was observed during the oestrous stage (May-August), during which the superficial cells accounted for >90% of the total vaginal cells. In addition, the detection of an average of 2.6 (±0.2) CL was associated with increased plasma progesterone concentrations (3.0 ± 0.4 ng/ml) between June and December (near hibernation). In conclusion, serial transrectal ultrasonography demonstrated yearly oestrous (ovulation) cycles via follicular dynamics and CL formation on ovaries, accordingly with vaginal cytology and hormonal level in the Asiatic black bear.


Asunto(s)
Ovario/diagnóstico por imagen , Reproducción , Ursidae/fisiología , Útero/diagnóstico por imagen , Animales , Cuerpo Lúteo/diagnóstico por imagen , Estradiol/sangre , Estro , Femenino , Hormonas/sangre , Folículo Ovárico/diagnóstico por imagen , Folículo Ovárico/fisiología , Ovulación , Progesterona/sangre , Recto , Estaciones del Año , Ultrasonografía , Vagina/citología
4.
Cancer Gene Ther ; 21(4): 158-63, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24626062

RESUMEN

14-3-3 proteins have important roles in several cellular processes such as cell cycle progression, the DNA-damage checkpoint and apoptosis. We have shown previously that depleting 14-3-3η, a 14-3-3 isoform, enhances mitotic cell death, and that combining it with microtubule agents is more effective for anticancer therapeutics. In this study, we investigated whether depleting 14-3-3η can be combined with radiotherapy to enhance its therapeutic efficacy. We found that depleting 14-3-3η resulted in a synergistic radiosensitizing effect when combined with radiotherapy in several glioblastoma cell lines, where its specific expression and correlation of its expression level with malignancy have been reported. The radiosensitizing effect was associated with enhanced mitotic cell death by 14-3-3η depletion but not with mitotic catastrophe, which is one of the major cell death mechanisms observed in response to irradiation of most solid tumors. These results suggest that 14-3-3η may be a therapeutic target to overcome radioresistance in glioblastoma.


Asunto(s)
Proteínas 14-3-3/deficiencia , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/radioterapia , Glioblastoma/metabolismo , Glioblastoma/radioterapia , Proteínas 14-3-3/genética , Proteínas 14-3-3/metabolismo , Apoptosis/efectos de la radiación , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Ciclo Celular/efectos de la radiación , Muerte Celular/efectos de la radiación , Procesos de Crecimiento Celular/efectos de la radiación , Línea Celular Tumoral , Supervivencia Celular/efectos de la radiación , Glioblastoma/genética , Glioblastoma/patología , Células HeLa , Humanos , Mitosis/efectos de la radiación , ARN Interferente Pequeño/administración & dosificación , ARN Interferente Pequeño/genética , Tolerancia a Radiación/fisiología , Transfección
5.
Int J Gynecol Cancer ; 16(3): 1234-40, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16803511

RESUMEN

This study was conducted to investigate the promoter methylation status of the p16, DAPK, CDH1, and TIMP-3 genes in primary cervical cancer and its correlation with clinicopathologic characteristics. Promoter methylation was evaluated using a methylation-specific polymerase chain reaction in 78 cervical cancer tissue specimens and 24 control, normal cervical tissue specimens. Clinicopathologic parameters were obtained from medical records, and the relationship between the discrete variables and the methylation status was evaluated. The frequencies of promoter methylation of p16, DAPK, CDH1, and TIMP-3 in cervical cancer were 57%, 44.9%, 52.6%, and 9%, respectively. Primary cervical cancer had significantly higher methylation frequencies for the p16 and DAPK promoters than did the control, normal cervix (P < 0.0001). The promoter methylation of TIMP-3 was significantly higher in adenocarcinoma than in squamous cell carcinoma (41.7% vs 3%, respectively, P= 0.0175). High-stage cancers exhibited an increased promoter methylation frequency for p16 (P= 0.0061). The promoter methylation of the p16 gene is a frequent event in cervical carcinogenesis and may have potential clinical application as a marker for the progression and prognosis of cancer.


Asunto(s)
Proteínas Reguladoras de la Apoptosis/metabolismo , Proteínas Quinasas Dependientes de Calcio-Calmodulina/metabolismo , Carcinoma/genética , Inhibidor p16 de la Quinasa Dependiente de Ciclina/metabolismo , Metilación de ADN , Regiones Promotoras Genéticas , Inhibidor Tisular de Metaloproteinasa-3/metabolismo , Neoplasias del Cuello Uterino/genética , Adulto , Factores de Edad , Anciano , Carcinoma/metabolismo , Carcinoma/patología , Cuello del Útero/metabolismo , ADN de Neoplasias/metabolismo , Proteínas Quinasas Asociadas a Muerte Celular , Femenino , Regulación Neoplásica de la Expresión Génica , Genes Relacionados con las Neoplasias , Humanos , Metástasis Linfática , Persona de Mediana Edad , Neoplasias del Cuello Uterino/metabolismo , Neoplasias del Cuello Uterino/patología
6.
Vet Pathol ; 42(2): 230-2, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15753480

RESUMEN

Hepatocellular carcinoma (HCC) with metastasis to the spleen in a Holstein cow was studied by histopathologic and immunohistochemical methods. The tumor was characterized by a pseudoglandular (acinar) pattern with an associated fibrous stroma. Individual cells often had a "hepatoid" appearance but were interspersed with scattered cells exhibiting a clear, periodic acid-Schiff (PAS)-positive cytoplasm and small eccentric nuclei. This pattern was present in nodules found in both liver and spleen. Moreover, hepatoid tumor cells were positive for alpha-fetoprotein. Immunohistochemical studies suggest that myofibroblasts were responsible for the production of fibrous septa surrounding the pseudoglandular structures of bovine HCC. In summary, our histologic and immunohistochemical findings support a diagnosis of primary HCC with splenic metastasis. Furthermore, the associated stromal response appears to be of a myofibroblast origin. The primary etiology of bovine HCC and the significance of the intralesional, PAS-positive clear cells remain undetermined.


Asunto(s)
Carcinoma Hepatocelular/veterinaria , Enfermedades de los Bovinos/diagnóstico , Neoplasias Hepáticas/veterinaria , Neoplasias del Bazo/veterinaria , Animales , Carcinoma Hepatocelular/secundario , Bovinos , Femenino , Neoplasias Hepáticas/patología , Neoplasias del Bazo/secundario
7.
J Am Chem Soc ; 123(1): 76-86, 2001 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-11273603

RESUMEN

The molecular design of directly meso-meso-linked porphyrin arrays as a new model of light-harvesting antenna as well as a molecular photonic wire was envisaged to bring the porphyrin units closer for rapid energy transfer. For this purpose, zinc(II) 5,15-bis(3,5-bis(octyloxy)phenyl)porphyrin (Z1) and its directly meso-meso-linked porphyrin arrays up to Z128 (Zn, n represents the number of porphyrins) were synthesized. The absorption spectra of these porphyrin arrays change in a systematic manner with an increase in the number of porphyrins; the high-energy Soret bands remain at nearly the same wavelength (413-414 nm), while the low-energy exciton split Soret bands are gradually red-shifted, resulting in a progressive increase in the exciton splitting energy. The exciton splitting is nicely correlated with the values of cos[pi/(N + 1)] according to Kasha's exciton coupling theory, providing a value of 4250 cm(-1) for the exciton coupling energy in the S(2) state. The increasing red-shifts for the Q-bands are rather modest. The fluorescence excitation anisotropy spectra of the porphyrin arrays show that the photoexcitation of the high-energy Soret bands exhibits a large angle difference between absorption and emission dipoles in contrast with the photoexcitation of the low-energy exciton split Soret and Q-bands. This result indicates that the high-energy Soret bands are characteristic of the summation of the individual monomeric transitions with its overall dipole moment deviated from the array chain direction, while the low-energy Soret bands result from the exciton splitting between the monomeric transition dipoles in line with the array chain direction. From the fluorescence quantum yields and fluorescence lifetime measurements, the radiative coherent length was estimated to be 6-8 porphyrin units in the porphyrin arrays. Ultrafast fluorescence decay measurements show that the S(2) --> S(1) internal conversion process occurs in less than 1 ps in the porphyrin arrays due to the existence of exciton split band as a ladder-type deactivation channel, while this process is relatively slow in Z1 (approximately 1.6 ps). The rate of this process seems to follow the energy gap law, which is mainly determined by the energy gap between the two Soret bands of the porphyrin arrays.

8.
J Gastroenterol ; 36(1): 24-32, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11211207

RESUMEN

To analyze the aberrant expression of cell cycle-related proteins and their biological significance in relation to cirrhosis, we compared the cirrhotic patterns induced by two different types of cirrhotic agents, CCl4 and thioacetamide (TAA) in rats. CCl4 or TAA treatment was given to rats for 8 or 30 weeks, respectively, and the livers were removed at 9, 20, and 30 weeks after the experiment began. The TAA-induced fibrotic pattern was different from the CCl4-induced one, in terms of the formation of fibrous connective tissue and the proliferation of bile ductule cells. Cholangiofibrosis and clear cell foci were also observed in TAA-treated rats at 30 weeks. Histological examination revealed severe cirrhotic changes at 9 weeks in CCl4-treated rats and at 30 weeks in TAA-treated rats. Immunoblotting for cyclin D1, E, A, B, and proliferating cell nuclear antigen (PCNA) and their counterpart protein kinases (CDK2, 4, and CDC2) showed significant overexpression in rats with severely cirrhotic livers. The p53 tumor suppressor protein increased dramatically in the CCl4-treated group, while it was not detected in the livers of TAA-treated rats. Upregulation of p21WAF1, a CDK inhibitory protein, was detected in TAA-treated rats, but not in CCl4-treated rats. Immunohistochemical data for cyclin D1, E, and PCNA were well correlated with immunoblotting data; these proteins were increased in hepatocytes surrounding the cirrhotic lesions, suggesting that hepatocyte regeneration is correlated with cell cycle-related protein expression in cirrhotic liver. In the TAA-treated rats, the expression of these proteins was increased both in hepatocytes and in ductule cells. Our data suggest that liver cirrhosis induced by CCl4 or TAA is associated with alterations in cell cycle-related proteins, and that the expression of these proteins is responsible for hepatocyte regeneration in the damaged liver and may be involved in liver carcinogenesis.


Asunto(s)
Proteínas de Ciclo Celular/biosíntesis , Cirrosis Hepática/metabolismo , Animales , Tetracloruro de Carbono/administración & dosificación , Modelos Animales de Enfermedad , Cirrosis Hepática/inducido químicamente , Cirrosis Hepática/patología , Masculino , Ratas , Ratas Endogámicas F344 , Tioacetamida/administración & dosificación
9.
J Gastroenterol Hepatol ; 16(1): 34-40, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11206314

RESUMEN

BACKGROUND AND AIMS: Protein kinase C (PKC) plays a key role in the alteration of signal transduction in the liver, which may contribute to the development of liver cirrhosis. The aim of the present study was to examine the subcellular redistribution of PKC isozymes in rat liver cirrhosis, which is induced by two different cirrhotic chemical agents, carbon tetrachloride (CCl4) and thioacetamide (TAA). METHODS AND RESULTS: Thioacetamide and CCl4 were administered to rats for 8 and 30 weeks, respectively before rats were killed and autopsies performed at 9, 20 and 30 weeks later. The TAA induced a fibrotic pattern in the liver that differed from that produced by CCl4, notably in the formation of fibrous connective tissue and the proliferation of bile ductule cells. Cholangiofibrosis and clear-cell foci were also observed in TAA-treated rats at 30 weeks. Histological examination revealed that severe cirrhotic changes were present 9 weeks after the commencement of CCl4 treatment and 30 weeks after TAA treatment. DISCUSSION: When the subcellular redistribution of PKC isozymes (PKCalpha, -beta1, -delta, and -epsilon) was examined, all the PKC isozymes in CCl4-treated rats were found to be translocated to the membrane fraction, which may mean PKC activation, and then downregulated by proteolytic degradation after 9 weeks of treatment, which coincided with peak cirrhotic changes. All rats treated with CCl4 recovered to the control level after 20 weeks of treatment. In the case of TAA-treated rats, PKC isozymes were translocated to the particulate fraction of the liver after 9 weeks of treatment and this persisted in most of the rats for the duration of the experiment. CONCLUSIONS: From these results, it would appear that PKC translocation preceded morphologic changes, and that an altered subcellular distribution of the PKC isozyme may be associated with the response to liver damage and carcinogenesis.


Asunto(s)
Tetracloruro de Carbono/farmacología , Cirrosis Hepática/enzimología , Proteína Quinasa C/metabolismo , Tioacetamida/farmacología , Animales , Colágeno/metabolismo , Activación Enzimática/efectos de los fármacos , Immunoblotting , Cirrosis Hepática/inducido químicamente , Masculino , Proteína Quinasa C/efectos de los fármacos , Ratas , Ratas Endogámicas F344 , Transducción de Señal/efectos de los fármacos
10.
Plant J ; 22(6): 561-70, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10886776

RESUMEN

We have produced 22 090 primary transgenic rice plants that carry a T-DNA insertion, which has resulted in 18 358 fertile lines. Genomic DNA gel-blot and PCR analyses have shown that approximately 65% of the population contains more than one copy of the inserted T-DNA. Hygromycin resistance tests revealed that transgenic plants contain an average of 1.4 loci of T-DNA inserts. Therefore, it can be estimated that approximately 25 700 taggings have been generated. The binary vector used in the insertion contained the promoterless beta-glucuronidase (GUS) reporter gene with an intron and multiple splicing donors and acceptors immediately next to the right border. Therefore, this gene trap vector is able to detect a gene fusion between GUS and an endogenous gene, which is tagged by T-DNA. Histochemical GUS assays were carried out in the leaves and roots from 5353 lines, mature flowers from 7026 lines, and developing seeds from 1948 lines. The data revealed that 1.6-2.1% of tested organs were GUS-positive in the tested organs, and that their GUS expression patterns were organ- or tissue-specific or ubiquitous in all parts of the plant. The large population of T-DNA-tagged lines will be useful for identifying insertional mutants in various genes and for discovering new genes in rice.


Asunto(s)
ADN Bacteriano/genética , Genoma de Planta , Mutagénesis Insercional , Oryza/genética , Secuencia de Bases , Southern Blotting , Genes Reporteros , Glucuronidasa/genética , Glucuronidasa/metabolismo , Oryza/metabolismo , Plantas Modificadas Genéticamente , Regiones Promotoras Genéticas
11.
Planta ; 210(4): 519-28, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10787044

RESUMEN

Two MADS-box genes, MdMADS3 and MdMADS4, were isolated from the apple (Malus x domestica Borkh.) cultivar Fuji, and their spatial and temporal expression patterns were studied during morphological differentiation of the flower buds and the fruits. Both MdMADS3 and MdMADS4 showed high sequence similarities to FBP2 from petunia, TM5 from tomato, and AGL2, AGL4 from Arabidopsis. Although MdMADS3 was expressed in the inner three whorls of the floral primordium, its expression was hardly detectable in developing fruit. The second gene, MdMADS4, was ubiquitously expressed in the inflorescence meristem, floral meristem, all four floral organs, and fruit. Moreover, MdMADS4 expression was high in the vascular bundles assigned to the floral tube and the carpellary vascular bundles in fruit at early developmental stages. The MdMADS4 transcript also accumulated in embryos of the developing seeds. These results suggest that MdMADS3 and MdMADS4 are involved in different functions, and that MdMADS4 may function in the important events controlling flower and fruit development.


Asunto(s)
Proteínas de Unión al ADN/genética , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Rosales/genética , Factores de Transcripción/genética , Secuencia de Aminoácidos , Proteínas de Unión al ADN/aislamiento & purificación , Proteínas de Unión al ADN/metabolismo , Frutas/genética , Frutas/crecimiento & desarrollo , Frutas/metabolismo , Proteínas de Dominio MADS , Meristema/genética , Meristema/crecimiento & desarrollo , Meristema/metabolismo , Datos de Secuencia Molecular , Filogenia , Proteínas de Plantas/aislamiento & purificación , Proteínas de Plantas/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Rosales/crecimiento & desarrollo , Rosales/metabolismo , Alineación de Secuencia , Factores de Transcripción/aislamiento & purificación , Factores de Transcripción/metabolismo
12.
J Korean Med Sci ; 15(1): 119-21, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10719823

RESUMEN

We present an unusual case of vascular sling, tracheal stenosis by complete cartilaginous ring, and aberrant left subclavian artery with right aortic arch that underwent successful surgical repair for the sling. These abnormalities were suspected from unusual multiple indentations found on esophagogram. Complete preoperative diagnosis was established with chest computerized tomogram combined with angiography.


Asunto(s)
Aorta Torácica/anomalías , Arteria Pulmonar/anomalías , Arteria Subclavia/anomalías , Niño , Humanos , Masculino , Estenosis Traqueal/congénito , Estenosis Traqueal/diagnóstico
13.
Mol Cells ; 8(5): 565-77, 1998 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-9856344

RESUMEN

In order to understand molecular events during fruit development and provide genetic resources for molecular breeding, 430 expressed sequence tags (ESTs) were generated from randomly selected clones of cDNA libraries prepared from young fruits, peels of mature fruits, and carpels of the Fuji apple (Malus domestica Borkh.). Database comparisons of the ESTs revealed that 180 non-redundant clones showed a high similarity with previously identified genes. Among these, 138 clones exhibited a homology with previously identified plant genes and 12 were identical to genes that were previously identified from apples. The deduced amino acid sequences of 42 clones had a homology to proteins that have not been reported from plants. Eighteen cDNA clones from the young fruit library were selected for studying expression levels and patterns in reproductive organs and leaves. This study revealed that the clones can be classified into 3 different groups based on their expression levels. The first 9 clones were expressed strongly in at least one reproductive organ. Eight of these clones (vacuolar processing protease, sucrose phosphate synthase, arabinogalactan protein, UDP-glucose glucosyl transferase, major allergen D1, cystein proteinase inhibitor, lipoxygenase, and protease subunit SUG2) were highly expressed in mature flowers and young fruits, whereas one clone (z-carotene desaturase protein precursor) was preferentially expressed in mature flowers but weakly in young fruits. The second group includes 6 cDNA clones (glucose transport protein, aminomethyl transferase precursor protein, dTDP-D-glucose-4,6-dehydrogenase, 2 types of protein kinase, and selenium binding protein) that were weakly expressed. These clones were characterized by their preferential expression patterns in mature flowers and young fruits. The transcripts of 3 cDNA clones in the third group (vacuolar aminopetidase, beta-galactosidase, and EREBP-4) were detectable only by RT-PCR and they were preferentially expressed in young fruits. These results indicate that most ESTs that were isolated from young fruits are preferentially expressed in reproductive organs and thereby play important roles during reproductive organ development.


Asunto(s)
Etiquetas de Secuencia Expresada , Frutas/genética , ARN Mensajero/genética , ADN Complementario/química , ADN Complementario/genética , Frutas/química , Frutas/crecimiento & desarrollo , Regulación del Desarrollo de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Biblioteca de Genes , Datos de Secuencia Molecular , ARN Mensajero/metabolismo , Alineación de Secuencia , Análisis de Secuencia de ADN , Distribución Tisular
14.
J Chromatogr B Biomed Sci Appl ; 701(1): 1-8, 1997 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-9389332

RESUMEN

A rapid profiling and screening procedure is described for the comparative analysis of urinary organic acids among the groups of nonsmokers and smokers. The procedure involves solid-phase extraction of organic acids using Chromosorb P in normal-phase partition mode, with subsequent single-step conversion to tert.-butyldimethylsilyl derivatives, followed by direct gas chromatographic (GC) analysis on dual-capillary columns. A total of forty-two organic acids were positively identified by retention index (I) matching in urine samples (0.25 ml) from eleven nonsmokers and fifteen smokers studied. When the GC profiles were simplified to their corresponding organic acid I spectra in bar graphical form, characteristic patterns were obtained for each individual as well as for each average of nonsmoking and smoking groups. When stepwise discriminant analysis was performed on GC data after omitting hippuric acid, seven acids were selected as the variables most discriminating between smokers and nonsmokers. The star symbol plots drawn based on these discriminants were characteristic of each individual and group average, enabling to distinguish smokers from nonsmokers. And canonical plot produced by canonical discriminant analysis using the same variables as the data vectors displayed two separate clusters representing each group.


Asunto(s)
Ácidos Carboxílicos/orina , Fumar/orina , Adulto , Cromatografía de Gases , Análisis Discriminante , Humanos , Masculino
15.
J Pharm Biomed Anal ; 15(9-10): 1309-18, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9226558

RESUMEN

An efficient method is described for the simultaneous determination of 57 amines including volatile aliphatic amines, nonvolatile polyamines and catecholamines present in aqueous samples. The method is based on two-phase isobutyloxycarbonylation (isoBOC) with a pH shift. In 1.0 M phosphate buffer at pH 7.5, phenolic hydroxyl groups were allowed to react with isobutyl chloroformate in the dichloromethane phase, and subsequently pH of the aqueous phase was increased to 12.0 for the reaction of basic amino functions. The resulting N(O)-isoBOC amines were recovered by solid-phase extraction using Chromosorb P in normal phase partition mode, with subsequent tert.- butyldimethylsilylation of the remaining hydroxyl groups for gas chromatographic analysis. Using this combined procedure, linear responses were obtained in the concentration range of 0.2-12 ppm, with correlation coefficients varying from 0.945 to 0.999 for most of the amines studied except for 5-methoxytryptamine (0.864). Temperature-programmed retention index (I) sets as measured on DB-5 and DB-17 dual-capillary columns of different polarity were characteristic of each amine and thus, useful in the screening for amines by computer I matching. When applied to saliva samples, the present method allowed rapid screening for each spiked amine and unspiked polyamines such as 1,3-diaminopropane, putrescine, cadaverine and spermidine.


Asunto(s)
Aminas/análisis , Cromatografía de Gases , Humanos , Concentración de Iones de Hidrógeno , Saliva/química , Factores de Tiempo
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