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1.
Braz J Med Biol Res ; 55: e12375, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36515351

RESUMO

The objective of this study was to evaluate the immunohistochemical expression of Dicer, Drosha, and Exportin-5 in the eutopic and ectopic endometrium of women with adenomyosis. Twenty-two paired ectopic and eutopic endometrium from women with adenomyosis and 10 eutopic endometrium samples from control women undergoing hysterectomy were included in the study. Paraffin-embedded tissue blocks were cut and stained for immunohistochemistry. The percentage of epithelial cells positively marked was identified digitally after an automated slide scanning process. Mann-Whitney test or Wilcoxon signed-rank test was performed for independent and paired groups, respectively. A lower expression of Drosha was observed in the eutopic endometrium of women with adenomyosis than in the eutopic endometrium of women without the disease (69.9±3.4% vs 85.2±2.9%, respectively) (P=0.016; 95%CI: 3.4 to 27.4%). We also detected lower Drosha expression in the ectopic endometrium of women with adenomyosis than in the eutopic endometrium of the same women (59.6±3.2% vs 69.9±3.4%, respectively) (P=0.004; 95%CI: 2.3 to 16.7%). Additionally, we observed a correlation between Drosha expression in the ectopic and paired eutopic endometrium (P=0.034, rho=0.454). No significant difference in Dicer or Exportin expression was observed. Predominant pattern of cytoplasmic staining for the anti-Drosha antibody and both a nuclear and cytoplasmic pattern for the anti-Exportin antibody were observed. Drosha expression was significantly lower in the endometrium of women with adenomyosis compared to the eutopic endometrium of asymptomatic women without the disease. Furthermore, its expression was lower in the ectopic endometrium but correlated to the paired eutopic endometrium.


Assuntos
Adenomiose , Endometriose , Feminino , Humanos , Adenomiose/metabolismo , Endométrio/metabolismo , Imuno-Histoquímica , Histerectomia , Células Epiteliais/metabolismo , Endometriose/metabolismo , Ribonuclease III/metabolismo
2.
Braz. j. med. biol. res ; 55: e12375, 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1420739

RESUMO

The objective of this study was to evaluate the immunohistochemical expression of Dicer, Drosha, and Exportin-5 in the eutopic and ectopic endometrium of women with adenomyosis. Twenty-two paired ectopic and eutopic endometrium from women with adenomyosis and 10 eutopic endometrium samples from control women undergoing hysterectomy were included in the study. Paraffin-embedded tissue blocks were cut and stained for immunohistochemistry. The percentage of epithelial cells positively marked was identified digitally after an automated slide scanning process. Mann-Whitney test or Wilcoxon signed-rank test was performed for independent and paired groups, respectively. A lower expression of Drosha was observed in the eutopic endometrium of women with adenomyosis than in the eutopic endometrium of women without the disease (69.9±3.4% vs 85.2±2.9%, respectively) (P=0.016; 95%CI: 3.4 to 27.4%). We also detected lower Drosha expression in the ectopic endometrium of women with adenomyosis than in the eutopic endometrium of the same women (59.6±3.2% vs 69.9±3.4%, respectively) (P=0.004; 95%CI: 2.3 to 16.7%). Additionally, we observed a correlation between Drosha expression in the ectopic and paired eutopic endometrium (P=0.034, rho=0.454). No significant difference in Dicer or Exportin expression was observed. Predominant pattern of cytoplasmic staining for the anti-Drosha antibody and both a nuclear and cytoplasmic pattern for the anti-Exportin antibody were observed. Drosha expression was significantly lower in the endometrium of women with adenomyosis compared to the eutopic endometrium of asymptomatic women without the disease. Furthermore, its expression was lower in the ectopic endometrium but correlated to the paired eutopic endometrium.

3.
Hum Reprod ; 34(12): 2381-2390, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31796963

RESUMO

STUDY QUESTION: Compared to healthy women, is the profile of transcripts altered in the eutopic endometrium of infertile women with endometriosis during the implantation window (IW)? SUMMARY ANSWER: The eutopic endometrium of infertile women with endometriosis seems to be transcriptionally similar to the endometrium of infertile and fertile controls (FC) during the IW. WHAT IS KNOWN ALREADY: Endometriosis is a disease related to infertility; nevertheless, little is known regarding the ethiopathogenic mechanisms underlying this association. Some studies evaluating the eutopic endometrium of endometriosis patients suggest there is an endometrial factor involved in the disease-related infertility. However, no study to date has evaluated the endometrial transcriptome (mRNA and miRNA) by next generation sequencing (NGS), comparing patients with endometriosis as the exclusive infertility factor (END) to infertile controls (IC; male and/or tubal factor) and FC. STUDY DESIGN, SIZE, DURATION: From November 2011 to November 2015 we performed a case-control study, where 17 endometrial samples (six END, six IC, five FC) were collected during the IW. PARTICIPANTS/MATERIALS, SETTING, METHODS: All endometrial samples had the RNA extracted. Two libraries were prepared for each one (mRNA and miRNA), which were sequenced, respectively, at HISEQ 2500 (RNA-Seq) and MiSeq System (miRNA-Seq), Illumina. The normalization and differential expression were conducted in statistical R environment using DESeq2 package. qPCR was used for data validation, which were analyzed by Kruskal-Wallis test and Dunn posttest (P < 0.05). MAIN RESULTS AND THE ROLE OF CHANCE: RNA-Seq revealed no differentially expressed genes (DEG) among END, IC and FC groups. miRNA-Seq revealed three differentially expressed miRNAs (has-27a-5p, has-miR-150-5p, has-miR-504-5p) in END group compared to FC group. However, none of the miRNAs identified in the sequencing was validated by qPCR. LIMITATIONS, REASONS FOR CAUTION: The main limitation of this study was the small sample size evaluated as a result of the restrictive eligibility criteria adopted, limiting the generalization of the results obtained here. On the other hand, strict eligibility criteria, which eliminated factors potentially related to impaired endometrial receptivity, were required to increase the study's internal validity. WIDER IMPLICATIONS OF THE FINDINGS: This study brings new perspectives on the mechanisms involved in endometriosis-related infertility. The present findings suggest the eutopic endometrium of infertile women with endometriosis, without considering the disease's stage, is transcriptionally similar to controls during the IW, possibly not affecting receptivity. Further studies are needed to evaluate endometrial alterations related to endometriosis' stages. STUDY FUNDING/COMPETING INTEREST(S): This study received financial support from the Sao Paulo Research Foundation (FAPESP-Fundação de Amparo à Pesquisa do Estado de São Paulo; fellowship 2011/17614-6, MGB) and from the National Council for Scientific and Technological Development (CNPq-Conselho Nacional de Desenvolvimento Científico e Tecnológico; INCT-National Institutes of Hormones and Woman's Health, grant 471 943/2012-6, 309 397/2016-2, PAN; fellowship 140 137/2015-7, MGB). The authors have no conflicts of interest. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Endometriose/metabolismo , Endométrio/metabolismo , Infertilidade Feminina/metabolismo , Adulto , Estudos de Casos e Controles , Implantação do Embrião , Endometriose/complicações , Feminino , Perfilação da Expressão Gênica , Humanos , MicroRNAs/metabolismo , Estudos Prospectivos , Transcriptoma
4.
Braz J Med Biol Res ; 50(7): e5782, 2017 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-28678915

RESUMO

Endometriosis is a benign, estrogen-dependent disease with symptoms such as pelvic pain and infertility, and it is characterized by the ectopic distribution of endometrial tissue. The expression of the ID2, PRELP and SMOC2 genes was compared between the endometrium of women without endometriosis in the proliferative phase of their menstrual cycle and the eutopic and ectopic endometrium of women with endometriosis in the proliferative phase. Paired tissue samples from 20 women were analyzed: 10 from endometrial and peritoneal endometriotic lesions and 10 from endometrial and ovarian endometriotic lesions. As controls, 16 endometrium samples were collected from women without endometriosis in the proliferative phase of menstrual cycle. Analysis was performed by real-time polymerase chain reaction (PCR). There was no significant difference between gene expression in the endometrium of women with and without endometriosis. The ID2 gene expression was increased in the most advanced stage of endometriosis and in ovarian endometriomas, the PRELP was more expressed in peritoneal lesions, and the SMOC2 was highly expressed in both peritoneal and endometrioma lesions. Considering that the genes studied participate either directly or indirectly in cellular processes that can lead to cell migration, angiogenesis, and inappropriate invasion, it is possible that the deregulation of these genes caused the development and maintenance of ectopic tissue.


Assuntos
Endometriose/genética , Proteínas da Matriz Extracelular/genética , Glicoproteínas/genética , Proteína 2 Inibidora de Diferenciação/genética , Osteonectina/genética , Doenças Ovarianas/genética , Doenças Peritoneais/genética , Adolescente , Adulto , Estudos de Casos e Controles , Endometriose/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Feminino , Regulação da Expressão Gênica , Glicoproteínas/metabolismo , Humanos , Proteína 2 Inibidora de Diferenciação/metabolismo , Ciclo Menstrual , Osteonectina/metabolismo , Doenças Ovarianas/metabolismo , Doenças Peritoneais/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Adulto Jovem
5.
Climacteric ; 20(5): 462-466, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28622040

RESUMO

OBJECTIVES: To evaluate the expression of four genetic markers (PTEN, BCL2, MLH1, and CTNNB1), linked to endometrial carcinogenesis, in endometrial polyps of patients with and without postmenopausal bleeding in order to determine whether symptomatic endometrial polyps have a genetic phenotype similar to that of endometrial cancer. METHODS: Samples were obtained hysteroscopically from endometrial polyps of postmenopausal patients, and the expression of genetic markers involved in the pathogenesis of endometrial cancer (PTEN, BCL2, MLH1, and CTNNB1) was analyzed. The expression of these markers was then compared between patients with and without symptoms, which was characterized as postmenopausal bleeding. Other clinical characteristics of the patients, such as duration of menopause, polyp size, presence of systemic hypertension, diabetes mellitus, and smoking habits were also analyzed. RESULTS: Samples from a total of 60 patients were obtained, as calculated for a test power of 0.80. No statistical differences (p > 0.05) were observed between the two groups concerning the expression of the studied endometrial cancer risk factor genes, or with regard to the clinical aspects evaluated. CONCLUSION: The study found no evidence that symptomatic endometrial polyps have a similar phenotype to type 1 endometrial cancer; further studies are needed in order to establish whether endometrial polyps are in fact true cancer precursors, or simply raise cancer incidence due to a detection bias.


Assuntos
Neoplasias do Endométrio/genética , Expressão Gênica , Marcadores Genéticos/genética , Pólipos/genética , Pós-Menopausa , Doenças Uterinas/genética , Idoso , Neoplasias do Endométrio/patologia , Neoplasias do Endométrio/cirurgia , Feminino , Humanos , Histeroscopia , Pessoa de Meia-Idade , Proteína 1 Homóloga a MutL/genética , PTEN Fosfo-Hidrolase/genética , Pólipos/patologia , Pólipos/cirurgia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Doenças Uterinas/patologia , Doenças Uterinas/cirurgia , Hemorragia Uterina , beta Catenina/genética
6.
Braz. j. med. biol. res ; 50(7): e5782, 2017. graf
Artigo em Inglês | LILACS | ID: biblio-951699

RESUMO

Endometriosis is a benign, estrogen-dependent disease with symptoms such as pelvic pain and infertility, and it is characterized by the ectopic distribution of endometrial tissue. The expression of the ID2, PRELP and SMOC2 genes was compared between the endometrium of women without endometriosis in the proliferative phase of their menstrual cycle and the eutopic and ectopic endometrium of women with endometriosis in the proliferative phase. Paired tissue samples from 20 women were analyzed: 10 from endometrial and peritoneal endometriotic lesions and 10 from endometrial and ovarian endometriotic lesions. As controls, 16 endometrium samples were collected from women without endometriosis in the proliferative phase of menstrual cycle. Analysis was performed by real-time polymerase chain reaction (PCR). There was no significant difference between gene expression in the endometrium of women with and without endometriosis. The ID2 gene expression was increased in the most advanced stage of endometriosis and in ovarian endometriomas, the PRELP was more expressed in peritoneal lesions, and the SMOC2 was highly expressed in both peritoneal and endometrioma lesions. Considering that the genes studied participate either directly or indirectly in cellular processes that can lead to cell migration, angiogenesis, and inappropriate invasion, it is possible that the deregulation of these genes caused the development and maintenance of ectopic tissue.


Assuntos
Humanos , Feminino , Adolescente , Adulto , Adulto Jovem , Doenças Peritoneais/genética , Glicoproteínas/genética , Osteonectina/genética , Proteínas da Matriz Extracelular/genética , Endometriose/genética , Proteína 2 Inibidora de Diferenciação/genética , Glicoproteínas/metabolismo , Estudos de Casos e Controles , Regulação da Expressão Gênica , Proteínas da Matriz Extracelular/metabolismo , Endometriose/metabolismo , Proteína 2 Inibidora de Diferenciação/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Ciclo Menstrual
10.
Braz J Med Biol Res ; 43(8): 799-805, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20725696

RESUMO

Endometriosis is a complex and multifactorial disease. Chromosomal imbalance screening in endometriotic tissue can be used to detect hot-spot regions in the search for a possible genetic marker for endometriosis. The objective of the present study was to detect chromosomal imbalances by comparative genomic hybridization (CGH) in ectopic tissue samples from ovarian endometriomas and eutopic tissue from the same patients. We evaluated 10 ovarian endometriotic tissues and 10 eutopic endometrial tissues by metaphase CGH. CGH was prepared with normal and test DNA enzymatically digested, ligated to adaptors and amplified by PCR. A second PCR was performed for DNA labeling. Equal amounts of both normal and test-labeled DNA were hybridized in human normal metaphases. The Isis FISH Imaging System V 5.0 software was used for chromosome analysis. In both eutopic and ectopic groups, 4/10 samples presented chromosomal alterations, mainly chromosomal gains. CGH identified 11q12.3-q13.1, 17p11.1-p12, 17q25.3-qter, and 19p as critical regions. Genomic imbalances in 11q, 17p, 17q, and 19p were detected in normal eutopic and/or ectopic endometrium from women with ovarian endometriosis. These regions contain genes such as POLR2G, MXRA7 and UBA52 involved in biological processes that may lead to the establishment and maintenance of endometriotic implants. This genomic imbalance may affect genes in which dysregulation impacts both eutopic and ectopic endometrium.


Assuntos
Aberrações Cromossômicas , DNA/análise , Endometriose/genética , Doenças Ovarianas/genética , Adulto , Endometriose/patologia , Feminino , Humanos , Perda de Heterozigosidade , Pessoa de Meia-Idade , Hibridização de Ácido Nucleico/genética , Doenças Ovarianas/patologia , Reação em Cadeia da Polimerase
11.
Braz. j. med. biol. res ; 43(8): 799-805, Aug. 2010. tab, ilus
Artigo em Inglês | LILACS | ID: lil-554954

RESUMO

Endometriosis is a complex and multifactorial disease. Chromosomal imbalance screening in endometriotic tissue can be used to detect hot-spot regions in the search for a possible genetic marker for endometriosis. The objective of the present study was to detect chromosomal imbalances by comparative genomic hybridization (CGH) in ectopic tissue samples from ovarian endometriomas and eutopic tissue from the same patients. We evaluated 10 ovarian endometriotic tissues and 10 eutopic endometrial tissues by metaphase CGH. CGH was prepared with normal and test DNA enzymatically digested, ligated to adaptors and amplified by PCR. A second PCR was performed for DNA labeling. Equal amounts of both normal and test-labeled DNA were hybridized in human normal metaphases. The Isis FISH Imaging System V 5.0 software was used for chromosome analysis. In both eutopic and ectopic groups, 4/10 samples presented chromosomal alterations, mainly chromosomal gains. CGH identified 11q12.3-q13.1, 17p11.1-p12, 17q25.3-qter, and 19p as critical regions. Genomic imbalances in 11q, 17p, 17q, and 19p were detected in normal eutopic and/or ectopic endometrium from women with ovarian endometriosis. These regions contain genes such as POLR2G, MXRA7 and UBA52 involved in biological processes that may lead to the establishment and maintenance of endometriotic implants. This genomic imbalance may affect genes in which dysregulation impacts both eutopic and ectopic endometrium.


Assuntos
Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Aberrações Cromossômicas , DNA , Endometriose/genética , Doenças Ovarianas/genética , Endometriose/patologia , Perda de Heterozigosidade , Hibridização de Ácido Nucleico/genética , Doenças Ovarianas/patologia , Reação em Cadeia da Polimerase
12.
Braz J Med Biol Res ; 40(6): 793-7, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17581677

RESUMO

Pregnancy loss can be caused by several factors involved in human reproduction. Although up to 50% of cases remain unexplained, it has been postulated that the major cause of failed pregnancy is an error of embryo implantation. Transmembrane mucin-1 (MUC-1) is a glycoprotein expressed on the endometrial cell surface which acts as a barrier to implantation. The gene that codes for this molecule is composed of a polymorphic tandem repeat of 60 nucleotides. Our objective was to determine if MUC-1 genetic polymorphism is associated with implantation failure in patients with a history of recurrent abortion. The study was conducted on 10 women aged 25 to 35 years with no history of successful pregnancy and with a diagnosis of infertility. The control group consisted of 32 patients aged 25 to 35 years who had delivered at least two full-term live children and who had no history of abortions or fetal losses. MUC-1 amplicons were obtained by PCR and observed on agarose and polyacrylamide gel after electrophoresis. Statistical analysis showed no significant difference in the number of MUC-1 variable number of tandem repeats between these groups (P > 0.05). Our results suggest that there is no effect of the polymorphic MUC-1 sequence on the implantation failure. However, the data do not exclude MUC-1 relevance during embryo implantation. The process is related to several associated factors such as the mechanisms of gene expression in the uterus, specific MUC-1 post-translational modifications and appropriate interactions with other molecules during embryo implantation.


Assuntos
Aborto Habitual/genética , Implantação do Embrião/genética , Infertilidade Feminina/genética , Mucina-1/genética , Polimorfismo Genético , Adulto , Estudos de Casos e Controles , Eletroforese em Gel de Poliacrilamida , Feminino , Humanos , Reação em Cadeia da Polimerase , Gravidez
13.
Braz. j. med. biol. res ; 40(6): 793-797, June 2007. ilus
Artigo em Inglês | LILACS | ID: lil-452679

RESUMO

Pregnancy loss can be caused by several factors involved in human reproduction. Although up to 50 percent of cases remain unexplained, it has been postulated that the major cause of failed pregnancy is an error of embryo implantation. Transmembrane mucin-1 (MUC-1) is a glycoprotein expressed on the endometrial cell surface which acts as a barrier to implantation. The gene that codes for this molecule is composed of a polymorphic tandem repeat of 60 nucleotides. Our objective was to determine if MUC-1 genetic polymorphism is associated with implantation failure in patients with a history of recurrent abortion. The study was conducted on 10 women aged 25 to 35 years with no history of successful pregnancy and with a diagnosis of infertility. The control group consisted of 32 patients aged 25 to 35 years who had delivered at least two full-term live children and who had no history of abortions or fetal losses. MUC-1 amplicons were obtained by PCR and observed on agarose and polyacrylamide gel after electrophoresis. Statistical analysis showed no significant difference in the number of MUC-1 variable number of tandem repeats between these groups (P > 0.05). Our results suggest that there is no effect of the polymorphic MUC-1 sequence on the implantation failure. However, the data do not exclude MUC-1 relevance during embryo implantation. The process is related to several associated factors such as the mechanisms of gene expression in the uterus, specific MUC-1 post-translational modifications and appropriate interactions with other molecules during embryo implantation.


Assuntos
Adulto , Feminino , Humanos , Gravidez , Aborto Habitual/genética , /genética , Implantação do Embrião/genética , Infertilidade Feminina/genética , Polimorfismo Genético , Estudos de Casos e Controles , Eletroforese em Gel de Poliacrilamida , Reação em Cadeia da Polimerase
14.
J Anim Breed Genet ; 124(1): 42-6, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17302961

RESUMO

MUC1 is a transmembrane glycoprotein expressed on the apical surfaces of the uterine epithelial tissue with predicted functions in protection and cell-cell adhesion. These properties are closely related with the repetitive region [variable number of tandem repeats (VNTR)] of the extracellullar domain and with the O-glycosylation in their serine and threonine residues. This study describes a polymerase chain reaction (PCR) protocol to analyse MUC1 bovine genetic polymorphism and demonstrates the existence of a VNTR within the sites for O-glycosylation. Oligonucleotide primers based on the Bos taurus mucin (MUC1) gene sequence GenBank AF399757 were used to amplify five VNTR MUC1 alleles from a study group of 56 pure Nelore bovines. The number of repeats varied between 10 and 24, being more prevalent than the alleles with less number of repeats. The DNA sequence analysis revealed two repeats and one of them presented 100% homology with the bovine consensus sequence already reported. The second repeat showed codons that translate to serine and proline amino acids, which are conserved in the MUC1 of several species. This study is the first description of allelic variation and the VNTR structure in the Nelore breed MUC1 gene, and we suggest that this genetic variability can be tested for association with variation in reproductive traits in Nelore cattle.


Assuntos
Bovinos/genética , Mucina-1/genética , Polimorfismo Genético , Animais , Sequência de Bases , Primers do DNA , Frequência do Gene , Repetições Minissatélites/genética , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Homologia de Sequência
15.
J Anal Toxicol ; 24(7): 642-7, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11043673

RESUMO

The history and toxicological findings in a case of suicidal fatal strychnine poisoning are presented along with a description of the analytical methods. Detection and quantitation of strychnine in body fluids and tissues was performed by gas chromatography (GC) with nitrogen-phosphorus detection, using organic extraction and calibration by a standard addition method. Strychnine concentrations in subclavian blood (1.82 mg/mL), inferior vena cava blood (3.32 mg/mL), urine (3.35 mg/mL), bile (11.4 mg/mL), liver (98.6 mg/kg), lung (12.3 mg/kg), spleen (11.8 mg/kg), brain (2.42 mg/kg), and skeletal muscle (2.32 mg/kg) were determined. Confirmation of strychnine in blood and tissue was performed by GC with detection by tandem ion-trap mass spectrometry (MS). GC-MS-MS analysis, employing electron ionization followed by unit mass resolution and collision-induced dissociation of strychnine, resulted in confirmatory ions with mass-to-charge ratios of 334 (parent ion), 319, 306, 277, 261, 246, 233, and 220. Additional confirmation was provided by GC-MS-MS-MS analysis of each confirmatory ion, revealing an ion fragmentation pathway consistent with the molecular structure of strychnine. The case demonstrates body tissue and fluid distribution of strychnine in a fatal poisoning and the application of tandem MS in medical examiner casework.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Venenos/efeitos adversos , Estricnina/intoxicação , Suicídio , Adulto , Medicina Legal/métodos , Humanos , Masculino , Venenos/farmacocinética , Estricnina/farmacocinética , Distribuição Tecidual
17.
J AOAC Int ; 82(4): 982-90, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10444835

RESUMO

A method for detection, quantitation, and confirmation of more than 100 pesticides by gas chromatography (GC) with ion trap mass spectrometry (MS/MS) has been developed. The sensitivity of this method for many analytes is equal to or lower than those of selective GC detectors such as flame photometric detectors and electrolytic conductivity detectors. Using MS/MS, very low detection limits and good confirmation (1 precursor ion and 2 or more product ions) are achieved simultaneously. The entire list of pesticides is screened with 2 injections per sample. Samples are introduced onto the column by a temperature-programmed cold injection to maximize response. Each pesticide is run with its own unique set of parameters, which fragment the compound, retaining only the precursor ion. This ion is then refragmented to create a product spectrum. The selectivity of MS/MS gives a very clean spectrum, making compound identification and confirmation clear, even with a relatively dirty food matrix. If care is taken to maintain the injection port and guard column, this method can reliably identify and confirm more than 100 pesticides at the low parts-per-billion range.


Assuntos
Contaminação de Alimentos , Frutas/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Leite/química , Resíduos de Praguicidas/análise , Verduras/química , Animais , Sensibilidade e Especificidade
19.
J Anal Toxicol ; 18(6): 348-53, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7823543

RESUMO

For a human fatality involving suspected overdose with the anticholinergic agent benztropine, GC-MS analysis was utilized for identification, quantitation, and investigation of metabolism. Organic extracts of blood and urine were analyzed by a capillary-column gas chromatograph interfaced with an ion-trap mass spectrometer, which was programmed for wide-spectrum data acquisition. Electron impact and chemical ionization were used for benztropine detection. The chemical structures of the ion fragments are proposed. Benztropine-d3 was synthesized and used as an internal standard. Quantitative determinations of benztropine revealed 0.183 mg/L in blood and 7.12 mg/L in urine from the decedent. Drug concentrations were interpreted relative to the case findings, published data, and a limited evaluation of the therapeutic concentrations in psychiatric patients. In addition, the possible metabolic conversion to norbenztropine was investigated by the synthesis of the norbenztropine derivative. Chromatographic evaluation of samples from the case study did not reveal significant bioconversion via the N-desmethylation pathway.


Assuntos
Benzotropina/intoxicação , Adulto , Benzotropina/sangue , Benzotropina/urina , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Masculino , Suicídio
20.
Clin Chem ; 35(10): 2059-65, 1989 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2791273

RESUMO

This interlaboratory study was conducted to examine four erythrocyte protoporphyrin control materials from Aviv Biomedical, Helena Laboratories, Kaulson Laboratories, and the New York State Department of Health for use with hematofluorometers. Our principal aims were to monitor the stability of these materials at three different storage temperatures (room, refrigerator, freezer) and, where appropriate, to validate the manufacturer's target values. Measurements for the study were generated in three reference laboratories that used a total of five hematofluorometers, three from Environmental Science Associates and two from Aviv Biomedical. Each instrument was calibrated against a consensus acetic acid-ethyl acetate extraction procedure. We found the materials from Aviv to be the most stable, followed by the New York State material. However, the target values assigned by Aviv were not within the acceptable range determined by consensus. The target values assigned by Kaulson Laboratories for their materials did fall within the acceptable consensus range, but they were the least stable of the materials evaluated. The materials from Helena Laboratories were originally designed for use as calibrators with Helena's "ProtoFluor Z" hematofluorometer, which reports in different units. They were deemed unsuitable for use as control materials with the Aviv or Environmental Science Associates hematofluorometers because of the narrow range of values and the wide scatter of results.


Assuntos
Eritrócitos/análise , Fluorometria/normas , Laboratórios/normas , Porfirinas/sangue , Protoporfirinas/sangue , Acetatos , Estabilidade de Medicamentos , Humanos , Intoxicação por Chumbo/sangue , Protoporfirinas/isolamento & purificação , Controle de Qualidade , Padrões de Referência , Manejo de Espécimes , Espectrometria de Fluorescência , Temperatura
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