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1.
Malar J ; 22(1): 211, 2023 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-37468917

RESUMEN

BACKGROUND: Malaria is a major public health problem, particularly in the tropical regions of America, Africa and Asia. Plasmodium falciparum is not only the most widespread but also the most deadly species. The share of Plasmodium infections caused by the other species (Plasmodium ovale and Plasmodium malariae) is clearly underestimated. The objective of the study was to determine the molecular epidemiology of plasmodial infection due to P. malariae and P. ovale in Côte d'Ivoire. METHODS: The study was cross-sectional. The study participants were recruited from Abengourou, San Pedro and Grand-Bassam. Sample collection took place from May 2015 to April 2016. Questionnaires were administered and filter paper blood samples were collected for parasite DNA extraction. The molecular analysis was carried out from February to March 2021. A nested PCR was used for species diagnosis. The data was presented in frequencies and proportions. RESULTS: A total of 360 patients were recruited, including 179 men (49,7%) for 181 women (50,3%). The overall Plasmodium positive rate was 72.5% (261/360). The specific index was 77.4% and 1.5% for P. falciparum and P. malariae in mono-infection, respectively. There was also 15% P. falciparum and P. malariae co-infection, 3.4% P. falciparum and P. ovale co-infection and 2.3% P. falciparum, P. malariae and P. ovale triple-infection. Typing of P. ovale subspecies showed a significant predominance of P. ovale curtisi (81.2% of cases). CONCLUSION: Plasmodium falciparum remains the most prevalent malaria species in Côte d'Ivoire, but P. malariae and P. ovale are also endemic mostly in co-infection. Malaria elimination requires a better understanding of the specific epidemiological characteristics of P. malariae and P. ovale with a particular emphasis on the identification of asymptomatic carriers.


Asunto(s)
Coinfección , Malaria Falciparum , Malaria , Plasmodium ovale , Masculino , Humanos , Femenino , Plasmodium falciparum/genética , Côte d'Ivoire/epidemiología , Epidemiología Molecular , Coinfección/epidemiología , Coinfección/parasitología , Estudios Transversales , Prevalencia , Malaria Falciparum/epidemiología , Malaria Falciparum/parasitología , Malaria/epidemiología , Malaria/parasitología , Plasmodium ovale/genética , Plasmodium malariae/genética
2.
Clin Radiol ; 76(2): 160.e15-160.e25, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33046228

RESUMEN

AIM: To evaluate the clinicopathological and computed tomography (CT) and magnetic resonance imaging (MRI) findings of steatohepatitic hepatocellular carcinoma (SH-HCC). MATERIALS AND METHODS: Clinicopathological and radiological features were evaluated in 20 patients with SH-HCC. The diagnosis of SH-HCC was made histologically if the tumour had four of the following five characteristics: steatosis (>5% tumour cells), ballooning, Mallory-Denk bodies, interstitial fibrosis, and inflammation. All patients underwent dynamic CT and MRI. CT and MRI images were reviewed for morphological features including tumour size, presence, and distribution of fat, and patterns and degree of contrast enhancement. RESULTS: Obesity, hypertension, and history of heavy alcohol intake were common clinical findings observed in 10 (50%), 13 (65%), and 11 (55%) of the 20 patients, respectively. Steatosis and steatohepatitis were pronounced in the background liver in 12 (60%) and 10 (50%) patients, respectively. SH-HCC was moderately differentiated in 18 patients (90%) and well differentiated in two (10%). Pathologically, steatohepatitic features were diffuse in 12 (60%) of the 20 tumours and focal in eight (40%). Tumour size and the percentage of intratumoural steatosis were not correlated (r=0.17, p=0.47). On CT, 16 (80%) patients showed arterial phase enhancement and delayed washout. On MRI, 16 (80%) of 20 tumours showed prominent fatty deposition (10 diffusely, six focally) with arterial phase enhancement. CONCLUSIONS: SH-HCC is likely to show prominent fatty deposits with arterial phase enhancement on CT and MRI. A hypervascular lesion with prominent fatty change should raise the diagnostic suspicion of SH-HCC.


Asunto(s)
Carcinoma Hepatocelular/diagnóstico por imagen , Hígado Graso/diagnóstico por imagen , Neoplasias Hepáticas/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma Hepatocelular/complicaciones , Carcinoma Hepatocelular/patología , Hígado Graso/complicaciones , Hígado Graso/patología , Femenino , Humanos , Hígado/diagnóstico por imagen , Hígado/patología , Neoplasias Hepáticas/complicaciones , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad
3.
Public Health ; 185: 80-86, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32574872

RESUMEN

OBJECTIVES: Family caregiver burden is associated with higher psychological distress. However, little is known about the impact of neighbourhood relationships on caregivers' psychological distress. We examined whether neighbourhood relationships of caregivers moderate the association between family caregiver burden and psychological distress. STUDY DESIGN: This was a cross-sectional study. METHODS: We recruited 5321 Japanese adults who participated in the Japan Multi-Institutional Collaborative Cohort Study in the Okazaki area between 2013 and 2017. Participants completed self-reported questionnaires to measure psychological distress (Kessler 6: K6), subjective caregiver burden, and neighbourhood relationships. We performed a multivariable linear regression analysis in which caregiver burden was designated as an independent variable and the K6 score as a dependent variable, adjusting for demographics. The interaction term between caregiver burden and neighbourhood relationships was also included in the analysis. RESULTS: Data from a total of 5069 participants were included (mean age [standard deviation]: 63.1 years [10.3 years]; 2226 [43.9%] female). Caregiver burden was significantly and positively associated with psychological distress (compared with no burden, mild burden: ß = 0.24, P = 0.197; severe burden: ß = 0.60, P < 0.01; P for trend < 0.01). There was a significant negative interaction effect of caregiver burden × neighbourhood relationship on psychological distress (severe burden × good neighbourhood relationship: ß = -3.29, P < 0.01). CONCLUSIONS: A higher caregiver burden was associated with higher psychological distress, and neighbourhood relationships moderated this association. Our findings suggest that good neighbourhood relationships can buffer caregiving-associated psychological distress.


Asunto(s)
Cuidadores/psicología , Relaciones Interpersonales , Distrés Psicológico , Características de la Residencia , Adaptación Psicológica , Adulto , Anciano , Estudios de Cohortes , Estudios Transversales , Femenino , Humanos , Japón , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios
4.
Obes Sci Pract ; 3(4): 417-424, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-29259800

RESUMEN

Objective: Inconsistent results have been found in prior studies investigating the accuracy of self-reported waist circumference, and no study has investigated the validity of self-reported waist circumference among Japanese individuals. This study used the diagnostic standard of metabolic syndrome to assess the accuracy of individual's self-reported height, weight and waist circumference in a Japanese sample. Methods: Study participants included 7,443 Japanese men and women aged 35-79 years. They participated in a cohort study's baseline survey between 2007 and 2011. Participants' height, weight and waist circumference were measured, and their body mass index was calculated. Self-reported values were collected through a questionnaire before the examination. Results: Strong correlations between measured and self-reported values for height, weight and body mass index were detected. The correlation was lowest for waist circumference (men, 0.87; women, 0.73). Men significantly overestimated their waist circumference (mean difference, 0.8 cm), whereas women significantly underestimated theirs (mean difference, 5.1 cm). The sensitivity of self-reported waist circumference using the cut-off value of metabolic syndrome was 0.83 for men and 0.57 for women. Conclusions: Due to systematic and random errors, the accuracy of self-reported waist circumference was low. Therefore, waist circumference should be measured without relying on self-reported values, particularly in the case of women.

5.
Diagn Cytopathol ; 45(11): 963-970, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28834601

RESUMEN

BACKGROUND: ALK gene rearrangement is an important class of gene mutations in pulmonary adenocarcinoma. ALK-positive pulmonary adenocarcinoma exhibits characteristic histological features, such as signet ring cell carcinoma (SRCC) and a mucinous cribriform structure. However, when insufficient histological specimens are obtained, ALK-positivity must be predicted based on cytological features. The purpose of this study was to clarify the cytological characteristics of ALK-positive pulmonary adenocarcinoma. METHODS: We compared the cytological findings of 16 ALK-positive cases with 40 ALK-negative cases. We examined various cytoplasmic features of SRCC, including the presence of pink, yellow, or orange mucin; green, vacuolar, or vesicular cytoplasm; and green globular cytoplasmic secretions. We also examined whether the SRCC cells exhibited a pattern of individually scattered cells, the formation of cell clusters, and formation of a mucinous cribriform pattern. RESULTS: A univariate analysis showed that significantly frequent cytological findings included pink mucin, green cytoplasm, vacuolar cytoplasm, vesicular cytoplasm, green globular cytoplasmic secretions, an individually scattered pattern, cluster formation, and a mucinous cribriform structure (all, P < .05). A stepwise multivariate logistic regression analysis identified three significant contributing factors: pink mucin (P = .03), vesicular cytoplasm (P = .06), and an individually scattered pattern (P = .01) of SRCC. If the specimens showed two or three of these features, the sensitivity and specificity were both 88% for the prediction of ALK-positive cancers. CONCLUSION: Three cytological features of SRCC (pink mucin, vesicular cytoplasm, and an individually scattered pattern) could be useful cytological markers for the prediction of ALK-positive pulmonary adenocarcinoma.


Asunto(s)
Adenocarcinoma/patología , Biomarcadores de Tumor/metabolismo , Citoplasma/patología , Neoplasias Pulmonares/patología , Proteínas Tirosina Quinasas Receptoras/genética , Adenocarcinoma/genética , Adulto , Anciano , Quinasa de Linfoma Anaplásico , Biomarcadores de Tumor/genética , Citoplasma/metabolismo , Vesículas Citoplasmáticas/metabolismo , Vesículas Citoplasmáticas/patología , Femenino , Humanos , Neoplasias Pulmonares/genética , Masculino , Persona de Mediana Edad , Mucinas/metabolismo
7.
Malar J ; 10: 185, 2011 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-21740570

RESUMEN

BACKGROUND: The ACT recommended by WHO is very effective and well-tolerated. However, these combinations need to be administered for three days, which may limit adherence to treatment.The combination of dihydroartemisinin-piperaquine phosphate-trimethoprim (Artecom®, Odypharm Ltd), which involves treatment over two days, appears to be a good alternative, particularly in malaria-endemic areas. This study intends to compare the efficacy and tolerability of the combination dihydroartemisinin-piperaquine phosphate-trimethoprim (DPT) versus artemether-lumefantrine (AL) in the treatment of uncomplicated Plasmodium falciparum malaria in Cameroon, Ivory Coast and Senegal. METHODS: This was a randomized, controlled, open-label clinical trial with a 28-day follow-up period comparing DPT to AL as the reference drug. The study involved patients of at least two years of age, suffering from acute, uncomplicated Plasmodium falciparum malaria with fever. The WHO 2003 protocol was used. RESULTS: A total of 418 patients were included in the study and divided into two treatment groups: 212 in the DPT group and 206 in the AL group. The data analysis involved the 403 subjects who correctly followed the protocol (per protocol analysis), i.e. 206 (51.1%) in the DPT group and 197 (48.9%) in the AL group. The recovery rate at D14 was 100% in both treatment groups. The recovery rate at D28 was 99% in the DPT and AL groups before and after PCR results with one-sided 97.5% Confidence Interval of the rates difference > -1.90%. More than 96% of patients who received DPT were apyrexial 48 hours after treatment compared to 83.5% in the AL group (p < 0.001). More than 95% of the people in the DPT group had a parasite clearance time of 48 hours or less compared to approximately 90% in the AL group (p = 0.023). Both drugs were well tolerated. No serious adverse events were reported during the follow-up period. All of the adverse events observed were minor and did not result in the treatment being stopped in either treatment group. The main minor adverse events reported were vomiting, abdominal pain and pruritus. CONCLUSION: The overall efficacy and tolerability of DPT are similar to those of AL. The ease of taking DPT and its short treatment course (two days) may help to improve adherence to treatment. Taken together, these findings make this medicinal product a treatment of choice for the effective management of malaria in Africa.


Asunto(s)
Antimaláricos/administración & dosificación , Artemisininas/administración & dosificación , Etanolaminas/administración & dosificación , Fluorenos/administración & dosificación , Malaria Falciparum/tratamiento farmacológico , Quinolinas/administración & dosificación , Trimetoprim/administración & dosificación , Adolescente , Adulto , Animales , Antimaláricos/efectos adversos , Arteméter , Artemisininas/efectos adversos , Camerún , Niño , Preescolar , Côte d'Ivoire , Quimioterapia Combinada/efectos adversos , Quimioterapia Combinada/métodos , Etanolaminas/efectos adversos , Femenino , Fluorenos/efectos adversos , Humanos , Lumefantrina , Masculino , Persona de Mediana Edad , Quinolinas/efectos adversos , Senegal , Resultado del Tratamiento , Trimetoprim/efectos adversos , Adulto Joven
8.
Endoscopy ; 41(9): 746-50, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19681023

RESUMEN

BACKGROUND AND STUDY AIMS: Endoscopic submucosal dissection (ESD) has been reported to produce excellent treatment results for early gastric cancer. In terms of lesions that previously met the criteria for endoscopic mucosal resection (EMR), there is now controversy about which of the two methods is superior, and whether the two methods are comparable. PATIENTS AND METHODS: A total of 177 patients (202 lesions) with early gastric cancer who met the guidelines for EMR and who underwent either EMR or ESD were studied. The rates of en bloc resection, complete resection, local recurrence, and complications were compared between EMR and ESD. RESULTS: The overall en bloc and complete resection rates were lower in patients undergoing EMR than in those undergoing ESD (en bloc: 53.8 % vs. 94.3 %, P < 0.001; complete: 37.5 % vs. 92.6 %, P < 0.001). The overall 5-year recurrence-free rate was lower in the EMR group than in the ESD group (82.5 % vs. 100 %; P < 0.001). However, with regard to the tumor size, the two groups did not differ in en bloc ( P = 1.0) or complete resection rate ( P = 0.8) for tumors < or = 5 mm and in 5-year recurrence-free rate ( P = 0.19) for tumors < or = 10 mm. The mean time required for resection was longer for ESD than for EMR ( P < 0.001). Perforation and bleeding requiring blood transfusion occurred in a small percentage in the ESD group, but in none in the EMR group. CONCLUSION: In this study, EMR was comparable to ESD for the millimeter-sized lesions. We suggest that such small lesions might be well suited to treatment with EMR.


Asunto(s)
Adenocarcinoma/cirugía , Disección/métodos , Endoscopía Gastrointestinal , Neoplasias Gástricas/cirugía , Adenocarcinoma/patología , Anciano , Endoscopía Gastrointestinal/métodos , Femenino , Mucosa Gástrica/patología , Mucosa Gástrica/cirugía , Humanos , Japón , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/epidemiología , Neoplasias Gástricas/patología , Resultado del Tratamiento
12.
J Dairy Sci ; 88(3): 908-13, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15738224

RESUMEN

This study was conducted to identify false-positive outcomes and drug residues in milk samples over withdrawal times and to determine whether the positive results were caused by drug residues or natural inhibitors. A total of 73 milk samples over withdrawal times after the last intramammary infusion were collected from each treated quarter of cows and tested using the Delvotest SP assay. Reading time was 150, 165, and 180 min, and results of samples were recorded according to the color of the well containing the control milk sample. There were 24, 20, and 12 positive samples at the reading times of 150, 165, and 180 min, respectively. All 24 positive milk samples were heated at 82 degrees C for 5 min and retested to verify that the positive results were caused by drug residues or natural inhibitors. Twenty-one samples that exhibited positive results were negative after heat treatment, and drug residues were not identified by LacTek and Charm tests. However, 3 samples that exhibited positive results from heat treatment of 82 degrees C were positive for drugs. In our study, most positive results (89%) in the milk samples over withdrawal times were false-positive results by natural inhibitors. Moreover, the heat treatment is a fast, simple, and inexpensive method to remove false-positive results and has no effect on positive samples containing drugs. We suggest that heat treatment before screening tests is an effective way to reduce false-positive results in the milk samples.


Asunto(s)
Antibacterianos/análisis , Antibacterianos/uso terapéutico , Residuos de Medicamentos/análisis , Mastitis Bovina/tratamiento farmacológico , Leche/química , Animales , Bovinos , Color , Reacciones Falso Positivas , Femenino , Contaminación de Alimentos/análisis , Mastitis Bovina/metabolismo , Factores de Tiempo
13.
Lett Appl Microbiol ; 39(2): 178-80, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15242458

RESUMEN

AIMS: We report the identification of the bisphenol A (BPA) biodegradability in Streptomyces sp. strain isolated from river water. METHODS AND RESULTS: The water samples spiked with BPA (1 mg l(-1)) and the culture solution of Streptomyces sp. strain were placed at 30 degrees C for 10 days and were analysed by high-performance liquid chromatography. A half-life for BPA degradation was between 3 and 4 days. The removal rate of BPA was >90% for 10 days. CONCLUSIONS: These results show that the Streptomyces sp. strain isolated from river water has high BPA degradability. SIGNIFICANCE AND IMPACT OF THE STUDY: To our knowledge, this is the first report of BPA degradation by Streptomyces sp. strain.


Asunto(s)
Fenoles/metabolismo , Ríos/microbiología , Streptomyces/aislamiento & purificación , Streptomyces/metabolismo , Compuestos de Bencidrilo , Biodegradación Ambiental , Streptomyces/enzimología
14.
Int J Gynecol Cancer ; 12(5): 501-5, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12366670

RESUMEN

In this report, we describe a case of adenosarcoma of the uterine corpus with overgrown and poorly differentiated sarcoma. The patient was an 80-year-old Japanese woman with abnormal genital bleeding. The endocervical biopsy showed undifferentiated carcinoma, and a cytologic examination at that time revealed the presence of cell types ranging from dispersed spindle to round atypical cells, suggestive of mesenchymal origin. The resected uterus had a polypoid mass in the corpus of the uterus and a solid white mass with the appearance of frank malignancy in the endocervix. The phyllode pattern was evident in the polypoid lesion and a diagnosis of adenosarcoma with sarcomatous overgrowth was made. The epithelial component was atypical with occasional microinvasion, which mimicked rhabdomyoblasts, but was easily identified as microinvasion by positive staining for epithelial, but not myogenic, markers. This case stresses the importance of the cytologic smear in the identification of frank sarcoma in an adenosarcoma, and it furthermore highlights the usefulness of immunohistochemistry in the distinction of epithelial microinvasion from rhabdomyogenic differentiation.


Asunto(s)
Adenosarcoma/patología , Carcinoma/patología , Invasividad Neoplásica/patología , Sarcoma/patología , Neoplasias Uterinas/patología , Adenosarcoma/cirugía , Anciano , Anciano de 80 o más Años , Biopsia con Aguja , Carcinoma/cirugía , Resultado Fatal , Femenino , Humanos , Histerectomía/métodos , Inmunohistoquímica , Estadificación de Neoplasias , Ovariectomía/métodos , Sarcoma/cirugía , Neoplasias Uterinas/cirugía
15.
Arch Environ Contam Toxicol ; 43(3): 265-9, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12202920

RESUMEN

Recently, there is increasing interest in the microbial degradation of endocrine disruptors. This study was conducted to show the isolation and property of bacteria having bisphenol A (BPA) biodegradability in river water and to identify the difference of BPA degradation under aerobic and anaerobic conditions. Three river water samples spiked with BPA (1 mg/L) were rapidly degraded under aerobic conditions. The half-life for BPA degradation ranged from 2 to 3 days, and BPA was below detection limit (less than 0.005 mg/L) on the 10th day. But a decrease of BPA under anaerobic conditions was hardly identified at 30 degrees C for 10 days (less than 10%). Also, most bacteria (10 out of 11) isolated from three river waters had BPA biodegradability, but there were differences in removal rates of BPA (18% to 91%). Moreover, two strains that had high BPA biodegradability (about 90%) were identified as a Pseudomonas sp. and a Pseudomonas putida strain.


Asunto(s)
Estrógenos no Esteroides/metabolismo , Fenoles/metabolismo , Pseudomonas putida/aislamiento & purificación , Pseudomonas/aislamiento & purificación , Contaminantes Químicos del Agua/metabolismo , Compuestos de Bencidrilo , Biodegradación Ambiental , Pseudomonas/fisiología , Pseudomonas putida/fisiología , Microbiología del Agua
16.
J Med Microbiol ; 51(1): 86-89, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11800478

RESUMEN

A new combined filtration-enrichment culture followed by a PCR technique for the rapid detection of Campylobacterjejuni and C. coli in human faeces has been developed. Only bacteria that passed through the membrane could multiply in the enrichment culture; target bacteria were detected by a one-step duplex PCR technique with combinations of primers that are specific for different Campylobacter spp., which should allow for the detection of a mixed infection in a single patient. A Falcon cell-culture insert and 24-well tissue-culture plates were used. After 2 days, both C. jejuni and C. coli were reliably detected in diluted faeces that were seeded with as few as 10 cells which corresponds to a concentration of 10(3) cfu/g. Even allowing for the dilution of faecal samples, this represents an increase in sensitivity of two-to-three orders of magnitude over the conventional filtration method.


Asunto(s)
Campylobacter coli/aislamiento & purificación , Campylobacter jejuni/aislamiento & purificación , Heces/microbiología , Reacción en Cadena de la Polimerasa/métodos , Campylobacter coli/genética , Campylobacter jejuni/genética , Recuento de Colonia Microbiana , Medios de Cultivo , Cartilla de ADN , Filtración , Humanos , Filtros Microporos , Sensibilidad y Especificidad , Especificidad de la Especie
17.
J Endotoxin Res ; 7(5): 349-58, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11753203

RESUMEN

Campylobacter jejuni infection is an important trigger of Guillain-Barré syndrome (GBS), and serotype HS:19 strains are over-represented among GBS-associated isolates. Structures in C. jejuni lipooligosaccharide (LOS) resemble human gangliosides, suggesting that molecular mimicry could be important in triggering the neural injury. We assessed the genetic diversity among 36 C. jejuni serotype HS:19 and non-HS:19 strains by analysis of PCR-based restriction fragment length polymorphism (RFLP) patterns of 12 LOS biosynthesis-related genes (wla cluster). PCR amplification revealed that the size, order, and direction of each wla gene was identical among all strains tested. However, an additional ORF, located between wlaI and wlaK, was detected in 28 of the 36 isolates examined, and nucleotide sequence analysis revealed that the gene was identical to orfE in C. jejuni strain NCTC 11168. An inverted repeat motif was found downstream of the wlaI stop codon and upstream of the orfE stop codon, an organization allowing pairing of repeated sequences that could lead to deletion of the internal segment. Digestion of the PCR products with restriction endonuclease DdeI or AluI and cluster analysis of RFLP banding patterns showed that all HS:19 strains were closely related and distinct from non-HS:19 strains, consistent with earlier analyses, suggesting that HS:19 strains represent a highly clonal population. RFLP analysis of wla genes also may be useful for epidemiological studies.


Asunto(s)
Campylobacter jejuni/genética , ADN Bacteriano/genética , Secuencia de Bases , Infecciones por Campylobacter/inmunología , Infecciones por Campylobacter/microbiología , Campylobacter jejuni/clasificación , ADN Bacteriano/análisis , Eliminación de Gen , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Serotipificación
18.
J AOAC Int ; 84(5): 1636-42, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11601486

RESUMEN

Microcystins, the cyclic heptapeptide toxins produced by cyanobacteria such as Microcystis sp., show potent hepatotoxicity and tumor-promoting activity through inhibition of protein phosphatases 1 and 2A. A toxic incident resulting in the death of 50 people in Brazil in 1996 was due to microcystins in water used for hemodialysis. Microcystins are now threatening human health and life, but many problems associated with microcystins remain unsolved. This report describes how to analyze trace amounts of microcystins in complicated matrixes such as liver tissue, lake water, and sediments.


Asunto(s)
Toxinas Bacterianas/análisis , Agua Dulce/análisis , Péptidos Cíclicos/análisis , Animales , Cromatografía Liquida , Cianobacterias/química , Citosol/química , Hígado/química , Masculino , Microcistinas , Ozono/química , Ratas , Ratas Wistar , Espectrofotometría Ultravioleta , Contaminantes del Agua/análisis
19.
Environ Toxicol ; 16(4): 298-305, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11501278

RESUMEN

The relationship between Microcystis composition and the production of microcystins and nontoxic peptides in bloom cells, which was regularly collected in Lake Suwa, Japan, in the summer season from 1991 to 1994, was investigated. In order to determine the structures of the nontoxic peptides, we collected large amounts of bloom materials from the same lake on July 23, 1991, and isolated three nontoxic peptides. They were named as aeruginopeptins 917S-A, -B, and -C, and their structures were mainly determined by a mass spectrometry/mass spectrometry (MS/MS) technique as 19-membered cyclic depsipeptides possessing the Ahp (3-amino-6-hydroxy-2-piperidone) moiety. An analysis of the microcystins and aeruginopeptins in the collected blood cells and their Microcystis composition suggested that the M. aeruginosa large cell size produces both microcystins and aeruginopeptins, and the production of both compounds is genetically closely related.


Asunto(s)
Cianobacterias , Eutrofización , Oligopéptidos/análisis , Péptidos Cíclicos/análisis , Tamaño de la Célula , Monitoreo del Ambiente , Espectrometría de Masas , Microcistinas , Oligopéptidos/biosíntesis , Péptidos Cíclicos/biosíntesis
20.
J Food Prot ; 64(8): 1211-5, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11510662

RESUMEN

Three hundred twenty-one quarter, 207 whole udder, 310 bulk tank, and 93 tank-lorry milk samples were examined for confirmation of the presence of inhibitor by Delvotest SP assay. Four hundred twenty-six Holstein cows of no drug treatment for at least 30 days from January 1998 to September 1999 were used. Reading time was 2.50, 2.75, and 3.00 h, and results of sampling were recorded by four types according to comparison with the color of the well containing the control milk sample. False-positive outcome was identified by Delvotest SP assay in quarter (13 of 321), whole udder (9 of 207), and bulk tank milk samples (4 of 310), but was not shown on tank-lorry milk samples (0 of 93) at the reading time of 2.50 h. All of the 26 false-positive samples were negative from the examination after heat treatment at 82 degrees C for 5 min. But, two bulk tank milk samples that appeared to have positive results in LacTek and Charm II tests were positive from the test following heat treatment. Somatic cell counts (SCC) were related to the probability of a false-positive result. The more SCC increased, the more the occurrence of a false-positive result increased. In our investigations, 4 of 310 bulk tank milk samples at the reading time of 2.50 h produced false-positive results, and no false-positive results were apparent at a reading time of 2.75 h. Also, the occurrence of false-positive results in quarter and whole udder milk samples decreased when agar was cultured for 2.75 to 3.00 h. There were no false-positive results from tank-lorry milk samples. These results indicate that the Delvotest SP assay may provide a suitable means for the detection of drug residues in not only quarter and whole udder milk of cows but also in bulk tank and tank-lorry milk following reading times of 2.75 to 3.00 h.


Asunto(s)
Residuos de Medicamentos/análisis , Contaminación de Alimentos , Leche/química , Animales , Antibacterianos/análisis , Bovinos , Recuento de Células , Reacciones Falso Positivas , Femenino , Incidencia , Factores de Tiempo
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