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1.
Mar Pollut Bull ; 190: 114843, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36965263

RESUMO

Atlantic haddock (Melanogrammus aeglefinus) embryos bind dispersed crude oil droplets to the eggshell and are consequently highly susceptible to toxicity from spilled oil. We established thresholds for developmental toxicity and identified any potential long-term or latent adverse effects that could impair the growth and survival of individuals. Embryos were exposed to oil for eight days (10, 80 and 300 µg oil/L, equivalent to 0.1, 0.8 and 3.0 µg TPAH/L). Acute and delayed mortality were observed at embryonic, larval, and juvenile stages with IC50 = 2.2, 0.39, and 0.27 µg TPAH/L, respectively. Exposure to 0.1 µg TPAH/L had no negative effect on growth or survival. However, yolk sac larvae showed significant reduction in the outgrowth (ballooning) of the cardiac ventricle in the absence of other extracardiac morphological defects. Due to this propensity for latent sublethal developmental toxicity, we recommend an effect threshold of 0.1 µg TPAH/L for risk assessment models.


Assuntos
Gadiformes , Hidrocarbonetos Aromáticos , Poluição por Petróleo , Petróleo , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Humanos , Animais , Petróleo/toxicidade , Petróleo/análise , Gadiformes/metabolismo , Larva/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Poluentes Químicos da Água/análise
2.
Mar Pollut Bull ; 151: 110862, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32056644

RESUMO

Marine plastic debris can act as a reservoir of chemical additives that can pose a potential threat to sensitive ecosystems such as coral reefs. A survey of foam macrodebris collected on beaches indeed revealed high concentrations of hexabromocyclododecanes (ΣHBCDD) in polystyrene (PS) samples (up to 1940 µg g-1). Results also showed that PS fragments can still leach over 150 ng g-1 d-1 of ΣHBCDD (primarily as the α-isomer) for relatively long durations, and that these additives are readily bioaccumulated and well-retained by corals. Despite significant HBCDD bioaccumulation in coral tissue, short-term exposure to HBCDD or PS leachate had no considerable effect on coral photosynthetic activity, symbiont concentration and chlorophyll content. Exposure to the PS leachate did however cause consistent polyp retraction in nubbins over the 5-day exposure. This response was not observed in animals exposed to HBCDD alone, suggesting that another constituent of the leachate stressed corals.


Assuntos
Antozoários/fisiologia , Monitoramento Ambiental , Retardadores de Chama , Poliestirenos/análise , Poluentes Químicos da Água/análise , Animais , Recifes de Corais , Ecossistema
3.
Nat Prod Res ; 34(21): 3048-3053, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31084225

RESUMO

Volatile and semi-volatile compounds account for the odors, long valued in the perfumery industry, of the natural product, ambergris. Here we demonstrate application of solid phase micro extraction (SPME) and gas chromatography-mass spectrometry (GC-MS) to headspace analysis of the volatiles and semi-volatiles of jetsam ambergris. The samples collected in 2017/2018, ranged from a black, sticky material from New Zealand, likely recently ejected from a sperm whale, to a white solid found on a beach in Chile and radiocarbon-dated previously to be about 1000 years old. The traces of volatile/semi-volatile compounds extracted included, odorous γ-dihydroionone and odor-free pristane (2,6,10,14-tetramethylpentadecane), as the major constituents. The ratios of these to one another and to many other minor constituents, varied, depending on sample color and age.


Assuntos
Âmbar-Gris/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Microextração em Fase Sólida/métodos , Compostos Orgânicos Voláteis/análise , Chile , Nova Zelândia , Odorantes/análise , Terpenos/análise , Compostos Orgânicos Voláteis/química
4.
Sci Total Environ ; 694: 133682, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31386952

RESUMO

Extracts of produced waters from five mature Norwegian Sea oil fields were examined as total organic extracts (TOEs) and after fractionation into operationally-defined 'polar' and 'apolar' fractions. The TOEs and fractions were examined by gas chromatography (GC), GC-mass spectrometry (GC-MS), two dimensional GC-MS (GC × GC-MS) and liquid chromatography with high-resolution spectrometry (LC-HRMS) techniques. Low molecular weight aromatics, phenols and other common petroleum-derived hydrocarbons were characterized and quantified in the TOEs and fractions. In addition, a range of more uncommon polar and apolar constituents, including those likely derived from production chemicals, such as trithiolane, imidazolines and quaternary amine compounds (so-called 'quats'), were tentatively identified, using GC × GC-MS and LC-HRMS. The acute toxicity of the TOEs and subfractions was investigated using early life stages of the marine copepod Acartia tonsa. Toxicity varied significantly for different PW TOEs and subfractions. For some PWs, the toxicity was attributed mainly to the 'polar' components, while that of other PWs was associated mainly with the 'apolar' components. Importantly, the observed toxicity could not be explained by the presence of the commonly reported compounds only. Although, due to the vast chemical complexity even of the sub-fractions of the PW extracts, specific compounds driving the observed toxicity could be not be elucidated in this study, the proposed approach may suggest a way forward for future revisions of monitoring regimes for PW discharges.


Assuntos
Monitoramento Ambiental/métodos , Campos de Petróleo e Gás , Poluição por Petróleo , Poluentes Químicos da Água/toxicidade , Fracionamento Químico , Cromatografia Líquida , Cromatografia Gasosa-Espectrometria de Massas , Petróleo , Fenóis
5.
Environ Pollut ; 251: 212-220, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31078960

RESUMO

A multitude of recent studies have documented the detrimental effects of crude oil exposure on early life stages of fish, including larvae and embryos. While polycyclic aromatic hydrocarbons (PAHs), particularly alkyl PAHs, are often considered the main cause of observed toxic effects, other crude oil derived organic compounds are usually overlooked. In the current study, comprehensive two-dimensional gas chromatography coupled to mass spectrometry was applied to investigate the body burden of a wide range of petrogenic compounds in Atlantic haddock (Melanogrammus aeglefinus) and cod (Gadus morhua) embryos that had been exposed to sublethal doses of dispersed crude oil. Several groups of alkylated monoaromatic compounds (e.g. alkyl tetralins, indanes and alkyl benzenes), as well as highly alkylated PAHs, were found to accumulate in the fish embryos upon crude oil exposure. To investigate the toxicity of the monoaromatic compounds, two models (1-isopropyl-4-methyltetralin and 1-isopropyl-4-methylindane) were synthesized and shown to bioaccumulate and cause delayed hatching in developing embryos. Minor developmental effects, including craniofacial and jaw deformations and pericardial edemas, were also observed at the highest studied concentrations of the alkylindane.


Assuntos
Petróleo/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Peixes , Gadiformes/fisiologia , Gadus morhua/fisiologia , Hidrocarbonetos/farmacologia , Larva/efeitos dos fármacos , Petróleo/análise , Petróleo/toxicidade , Poluição por Petróleo/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Alimentos Marinhos/análise , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
6.
Anal Chem ; 89(5): 2919-2927, 2017 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-28194945

RESUMO

Identification of the heteroatom (nitrogen, sulfur, and oxygen)-containing compounds of petroleum is of key importance when considering industrial and environmental issues associated with crude oil production. The more commonly performed methods of crude oil fractionation are often insufficient in the extent to which they separate oils, not allowing defined "molecular" fractions to be obtained. Methods capable of performing a class type separation are uncommon and are often extensive and resource and time intensive. Here we report a method for the separation of crude oils into discrete compound classes. The method utilizes both ion exchange and normal phase chromatography to generate fractions of saturated hydrocarbons, aromatic hydrocarbons, basic compounds, naphthenic acids, and other oxygen-containing species, carbazoles, sulfones, and thiophenes from small crude oil samples (∼0.5 g). Assessment of method selectivity with a suite of model compounds has shown the fractions to be well-defined, with classes of model compounds isolated within discrete fractions. Application of the method to five crude oils of varying API gravity (12.1-38.3°) demonstrates a potential for wide-ranging use. Sample recoveries were high (77-98%) with simple evaporative losses correlating closely with total sample loss. Repeatability was also high, demonstrated by triplicate analyses of model compound mixtures, oils spiked with model compounds and oils alone. Separation selectivity was further demonstrated by application of the scheme to the Alaska North Slope (ANS) crude oil and analysis of fractions by comprehensive two-dimensional gas-chromatography mass-spectrometry (GC × GC/MS) and/or liquid-chromatography high-resolution accurate-mass mass-spectrometry methods (LC-HRAM-MS). Isolation of discrete fractions then allowed excellent separation (by LC and GC methods) of carbazole, dibenzothiophene, fluorenones, xanthones, and quinoline fractions. Individual parent and C1-5 alkyl homologues were easily separated (GC × GC/MS), allowing high-quality mass spectra (EI) to be obtained for the individual compounds in many cases. Analysis of fractions by GC × GC/MS also allowed a series of thioxanones to be identified.

7.
Pediatr Dermatol ; 25(2): 233-5, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18429787

RESUMO

We report four Chinese infants with a darker pigmented Mongolian spot superimposed on another Mongolian spot. The presence of a superimposed Mongolian spot has not been previously reported. Mongolian spots can look similar to a bruise and awareness of these lesions is important to avoid unjustified consideration of injury or child abuse.


Assuntos
Mancha Mongólica/patologia , Neoplasias Primárias Múltiplas/patologia , Neoplasias Cutâneas/patologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Regressão Neoplásica Espontânea/patologia , Exame Físico
8.
Adv Ther ; 24(5): 1016-9, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18029327

RESUMO

A sliding inguinal hernia is usually diagnosed during a surgical procedure rather than preoperatively. This report describes a 77-year-old man with a sliding vesicalinguinal-scrotal hernia. The preoperative diagnosis was established by a plain radiograph of the abdomen, which showed bladder calculi within the pelvic cavity and in the right groin area. A review of the literature revealed only 2 prior reported cases of bladder calculi within a vesical-inguinal-scrotal hernia.


Assuntos
Hérnia Inguinal/complicações , Hérnia Inguinal/diagnóstico por imagem , Escroto , Cálculos da Bexiga Urinária/diagnóstico por imagem , Idoso , Hérnia Inguinal/cirurgia , Humanos , Litotripsia , Masculino , Radiografia Abdominal , Cálculos da Bexiga Urinária/complicações , Cálculos da Bexiga Urinária/terapia
10.
Adv Ther ; 24(2): 353-61, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17565926

RESUMO

Pertussis is a highly communicable respiratory infection caused by Bordetella pertussis. In spite of the widespread availability of effective vaccines and high levels of vaccination coverage, a significant resurgence in pertussis has been observed during the past 2 decades. The increase in reported cases is due in large part to infection in adolescents and adults, and waning immunity plays an important role. Pertussis in adolescents and adults often goes unrecognized because a persistent, uncharacteristic cough might be the only clinical presentation. Pneumonia is the most frequent complication. Culture and polymerase chain reaction are helpful in establishing the diagnosis if a specimen can be obtained early in the course of the illness. Serology is useful when the diagnosis is not suspected until a later stage. Treatment with a macrolide antibiotic is recommended for affected individuals, as well as for all household and other close contacts. Universal immunization is necessary for disease control. Immunization should begin in infancy and should continue with booster doses through adulthood. Two adolescent and adult formulations of acellular pertussis vaccine are licensed in North America and Europe. Both are combined with an adult formulation of diphtheria and tetanus toxoids. In the US, Adacel (Sanofi Pasteur, Toronto, Ontario, Canada) is licensed for use in individuals aged 11 to 64 y while Boostrix (GlaxoSmithKline Biologicals, Rixensart, Belgium) is licensed for use in individuals aged 10 to 18 y. These vaccines are safe, immunogenic, and well tolerated. Routine vaccination of adolescents and adults is required for optimal control of pertussis.


Assuntos
Vacina contra Coqueluche , Coqueluche/epidemiologia , Coqueluche/prevenção & controle , Adolescente , Antibacterianos/uso terapêutico , Controle de Doenças Transmissíveis , Doenças Transmissíveis/tratamento farmacológico , Doenças Transmissíveis/epidemiologia , Humanos , Macrolídeos/uso terapêutico , Coqueluche/tratamento farmacológico
12.
Asian J Androl ; 9(1): 16-22, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17187155

RESUMO

Hypospadias is the most common congenital anomaly of the penis. The problem usually develops sporadically and without an obvious underlying cause. The ectopically positioned urethral meatus lies proximal to the normal site and on the ventral aspect of the penis, and in severe cases opens onto the scrotum or perineum. The foreskin on the ventral surface is deficient, while that on the dorsal surface is abundant, giving the appearance of a dorsal hood. Chordee is more common in severe cases. Cryptorchidism and inguinal hernia are the most common associated anomalies. The frequency of associated anomalies increases with the severity of hypospadias. For isolated anterior or middle hypospadias, laboratory studies are not usually necessary. Screening for urinary tract anomalies should be considered in patients with posterior hypospadias and in those with an anomaly of at least one additional organ system. The ideal age for surgical repair in a healthy child is between 6 and 12 months of age. Most cases can be repaired in a single operation and on an outpatient basis. Even patients with a less than perfect surgical result are usually able to enjoy a satisfactory sexual life.


Assuntos
Hipospadia/epidemiologia , Geografia , Humanos , Hipospadia/embriologia , Hipospadia/etiologia , Hipospadia/cirurgia , Incidência , Masculino , Pênis/anormalidades
13.
Adv Ther ; 23(4): 519-27, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17050494

RESUMO

Travelers' diarrhea is common. Between 8% and 50% of travelers develop diarrhea; incidence depends on the country visited. The attack rate is highest for travelers from a developed country who visit a developing country. Children are at particular risk. Travelers' diarrhea is usually acquired through ingestion of fecally contaminated food and water. Most cases are due to a bacterial pathogen, commonly, Escherichia coli, and occur within the first few days after arrival in a foreign country. More than 90% of episodes develop within the first 2 wk of initiation of travel. Dehydration is the most common complication. Water and electrolyte replenishment is important and can usually be accomplished with an oral rehydration solution. Judicious use of an antimotility agent and antimicrobial therapy reduces the duration and severity of diarrhea. Pretravel education on hygiene and on the safe selection of food items is important in minimizing episodes. Dukoraltrade mark (Aventis Pharma Ltd., Auckland, New Zealand) vaccine should be considered for travelers who are 2 y of age or older and who will be visiting an area associated with risk of infection due to enterotoxigenic E coli or Vibrio cholerae. Typhoid vaccine is recommended for travelers who will be visiting areas with poor sanitation and hygiene.


Assuntos
Disenteria/terapia , Hidratação , Viagem , Anti-Infecciosos/uso terapêutico , Antidiarreicos/uso terapêutico , Ensaios Clínicos como Assunto , Disenteria/epidemiologia , Disenteria/prevenção & controle , Microbiologia de Alimentos , Humanos
14.
J Natl Med Assoc ; 98(10): 1700-1, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17052066

RESUMO

We describe recurrent panniculitis in a 15-year-old boy with Prader-Willi syndrome. To our knowledge, this association has not been previously reported.


Assuntos
Paniculite/etiologia , Síndrome de Prader-Willi/complicações , Adolescente , Diagnóstico Diferencial , Seguimentos , Humanos , Masculino , Paniculite/diagnóstico , Recidiva , Remissão Espontânea
16.
J Natl Med Assoc ; 98(2): 226-8, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16708508

RESUMO

The incidence of natal teeth is approximately 1:2,000 to 1:3,000 live births. The most commonly affected teeth are the lower primary central incisors. Natal teeth usually occur in pairs. The eruption of more than two natal teeth is rare. The majority of natal teeth represent the early eruption of normal primary deciduous dentition. Less than 10% of natal teeth are supernumerary. Natal teeth might resemble normal primary dentition in size and shape; however, the teeth are often smaller, conical and yellowish, and have hypoplastic enamel and dentin with poor or absent root formation. Complications include discomfort during suckling, sublingual ulceration, laceration of the mother's breasts and aspiration of the teeth. A dental roentgenogram is indicated to differentiate the premature eruption of a primary tooth from a supernumerary tooth. Tooth extraction is indicated if the tooth is supernumerary or excessively mobile. If the tooth does not interfere with breastfeeding and is otherwise asymptomatic, no treatment is necessary.


Assuntos
Dentes Natais , Humanos , Extração Dentária , Dente Supranumerário , Estados Unidos
17.
J Natl Med Assoc ; 98(12): 2011-2, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17225851

RESUMO

Angioedema is characterized by transient, episodic, nonpruritic, nonpitting and well-defined edema that involves the subcutaneous or submucosal tissue, and most commonly develops in the head and neck region. Angioedema is caused by extravasation of plasma into the interstitial space of the affected tissue. We describe a six-year-old boy who developed oral and penile angioedema subsequent to the ingestion of peanuts.


Assuntos
Angioedema/etiologia , Lábio , Hipersensibilidade a Amendoim/complicações , Pênis , Angioedema/diagnóstico , Criança , Humanos , Masculino , Hipersensibilidade a Amendoim/diagnóstico
18.
J Natl Med Assoc ; 97(2): 281-3, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15712793

RESUMO

A healthy four-year-old boy developed a febrile urinary tract infection (UTI) due to Salmonella stanleyville. The UTI developed following an episode of enteritis due to the same organism. Salmonella UTI is uncommon and is reported more often in patients with a predisposing factor, such as immune deficiency or a structural abnormality, in the urinary tract. Salmonella stanleyville has not been previously reported as a cause of UTI.


Assuntos
Infecções por Salmonella/complicações , Salmonella/isolamento & purificação , Infecções Urinárias/microbiologia , Pré-Escolar , Gastroenterite/microbiologia , Humanos , Salmonella/classificação , Infecções por Salmonella/microbiologia , Sorotipagem , Especificidade da Espécie
19.
Adv Ther ; 22(6): 543-7, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16510371

RESUMO

A 3-year-old neurologically intact and behaviorally normal boy developed infrequent and difficult voiding subsequent to a soft tissue injury to the glans penis. Symptoms persisted for at least 9 months, and the course was complicated by diagnostic imaging evidence of a "markedly distended" bladder and a voiding diary that suggested elevated bladder volumes. Treatment with an alpha-1 receptor blocker normalized voiding within 24 hours. Discontinuation of the medication after 2 weeks resulted in recurrence of symptoms within 48 hours. Readministration of the medication resulted in prompt resolution of symptoms.


Assuntos
Antagonistas de Receptores Adrenérgicos alfa 1 , Doxazossina/uso terapêutico , Retenção Urinária/tratamento farmacológico , Pré-Escolar , Humanos , Masculino , Pênis/lesões , Retenção Urinária/etiologia
20.
Adv Ther ; 22(4): 363-7, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16418143

RESUMO

Dog bites to the external genitalia are rare. In this case, a 16-year-old boy suffered a dog bite wound to the penis. The wound was cleansed with copious amounts of sterile normal saline by means of high-pressure syringe irrigation. The child had an uneventful recovery.


Assuntos
Mordeduras e Picadas , Cães , Pênis/lesões , Adolescente , Animais , Humanos , Masculino , Pênis/patologia
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