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1.
Bull Environ Contam Toxicol ; 112(6): 82, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38822880

RESUMEN

Mercury contamination has been aggravated by emerging environmental issues, such as climate change. Top predators present concerning Hg concentrations once this metal bioaccumulates and biomagnifies. This study evaluated total mercury (THg) concentrations in tissues of 43 franciscanas (Pontoporia blainvillei) from two populations: the Franciscana Management Area (FMA) IIb and FMA IIIa. Animals from FMA IIIa showed mean concentration 5-times and 2.5-times higher in the liver and kidney (4.73 ± 6.84 and 0.52 ± 0.51 µg.g-1, w.w., respectively) than individuals from FMA IIb (0.89 ± 1.04 and 0.22 ± 0.15 µg.g-1, w.w., respectively). This might be due to: (I) individuals sampled from FMA IIIa being larger and older, and/or (II) the area near FMA IIIa presents environmental features leading to higher THg availability. Coastal contamination can affect franciscanas' health and population maintenance at different levels depending on their life history and, therefore, it should be considered to guide specific conservation actions.


Asunto(s)
Delfines , Especies en Peligro de Extinción , Monitoreo del Ambiente , Mercurio , Contaminantes Químicos del Agua , Animales , Mercurio/análisis , Mercurio/metabolismo , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/metabolismo , Océano Atlántico , Delfines/metabolismo , Hígado/metabolismo , Riñón/metabolismo
2.
Funct Integr Genomics ; 23(2): 171, 2023 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-37211553

RESUMEN

Metastasis is a multi-step process that leads to the dissemination of tumor cells to new sites and, consequently, to multi-organ neoplasia. Although most lethal breast cancer cases are related to metastasis occurrence, little is known about the dysregulation of each step, and clinicians still lack reliable therapeutic targets for metastasis impairment. To fill these gaps, we constructed and analyzed gene regulatory networks for each metastasis step (cell adhesion loss, epithelial-to-mesenchymal transition, and angiogenesis). Through topological analysis, we identified E2F1, EGR1, EZH2, JUN, TP63, and miR-200c-3p as general hub-regulators, FLI1 for cell-adhesion loss specifically, and TRIM28, TCF3, and miR-429 for angiogenesis. Applying the FANMOD algorithm, we identified 60 coherent feed-forward loops regulating metastasis-related genes associated with distant metastasis-free survival prediction. miR-139-5p, miR-200c-3p, miR-454-3p, and miR-1301-3p, among others, were the FFL's mediators. The expression of the regulators and mediators was observed to impact overall survival and to go along with metastasis occurrence. Lastly, we selected 12 key regulators and observed that they are potential therapeutic targets for canonical and candidate antineoplastics and immunomodulatory drugs, like trastuzumab, goserelin, and calcitriol. Our results highlight the relevance of miRNAs in mediating feed-forward loops and regulating the expression of metastasis-related genes. Altogether, our results contribute to understanding the multi-step metastasis complexity and identifying novel therapeutic targets and drugs for breast cancer management.


Asunto(s)
Neoplasias de la Mama , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Metástasis de la Neoplasia , Regulación Neoplásica de la Expresión Génica , Factores de Transcripción/genética , MicroARNs/genética , Redes Reguladoras de Genes , Humanos
3.
J Acoust Soc Am ; 154(5): 3158-3167, 2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37966334

RESUMEN

Fish choruses are still understudied in the Southwestern Atlantic Ocean. Temporal and spatial variation of fish choruses at two sites inside Guanabara Bay were investigated between 2021 and 2022; one sampling site was in a Marine Protected Area (MPA), and the other was in a rocky environment closer to vessel trafficking areas. Acoustic recordings were performed on 17 sampling occasions of 24 h, coupled to a temperature data logger. Long-term spectral averages were employed to determine choruses' start, end, and peak times, and third-octave levels were used to characterize spectral characteristics. Fish sounds were also analyzed and investigated with a principal components analysis. Choruses in the MPA lasted, on average, 4.5 h and had a peak frequency of 547.2 ± 226.6 kHz with a peak level of 104.6 ± 8.7 dB re 1 µPa. In contrast, the rocky site choruses lasted 5.5 h on average and had a peak frequency of 371.7 ± 131.0 Hz with a peak level of 113.4 ± 4.0 dB re 1 µPa. Chorus peak frequency was positively correlated to temperature (r = 0.4). Different types of fish sounds were identified, with some acoustics parameters varying between sites. Results indicate more than one chorusing species that may react to different factors.


Asunto(s)
Acústica , Peces , Animales , Océano Atlántico , Análisis de Componente Principal , Sonido
4.
Int J Mol Sci ; 24(16)2023 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-37628784

RESUMEN

In the oncological area, pancreatic cancer is one of the most lethal diseases, with 5-year survival rising just 10% in high-development countries. This disease is genetically characterized by KRAS as a driven mutation followed by SMAD4, CDKN2, and TP53-associated mutations. In clinical aspects, pancreatic cancer presents unspecific clinical symptoms with the absence of screening and early plasmatic biomarker, being that CA19-9 is the unique plasmatic biomarker having specificity and sensitivity limitations. We analyzed the plasmatic exosome proteomic profile of 23 patients with pancreatic cancer and 10 healthy controls by using Nanoscale liquid chromatography coupled to tandem mass spectrometry (NanoLC-MS/MS). The pancreatic cancer patients were subdivided into IPMN and PDAC. Our findings show 33, 34, and 7 differentially expressed proteins when comparing the IPMN vs. control, PDAC-No treatment vs. control, and PDAC-No treatment vs. IPMN groups, highlighting proteins of the complement system and coagulation, such as C3, APOB, and SERPINA. Additionally, PDAC with no treatment showed 11 differentially expressed proteins when compared to Folfirinox neoadjuvant therapy or Gemcitabine adjuvant therapy. So here, we found plasmatic exosome-derived differentially expressed proteins among cancer patients (IPMN, PDAC) when comparing with healthy controls, which could represent alternative biomarkers for diagnostic and prognostic evaluation, supporting further scientific and clinical studies on pancreatic cancer.


Asunto(s)
Exosomas , Neoplasias Intraductales Pancreáticas , Neoplasias Pancreáticas , Humanos , Detección Precoz del Cáncer , Pronóstico , Neoplasias Pancreáticas/diagnóstico , Protocolos de Quimioterapia Combinada Antineoplásica , Proteómica , Espectrometría de Masas en Tándem , Antígeno CA-19-9 , Neoplasias Pancreáticas
5.
Genet Mol Biol ; 46(4): e20220346, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38100720

RESUMEN

The LEF1/TCF transcription factor family is related to the development of diverse tissue types, including the mammary tissue, and dysregulation of its expression and function has been described to favor breast tumorigenesis. However, the clinical and biological relevance of this gene family in breast cancer is still poorly understood. Here, we used bioinformatics approaches aiming to reduce this gap. We investigated its expression patterns in molecular and immune breast cancer subtypes; its correlation with immune cell infiltration, and its prognostic values in predicting outcomes. Also, through regulons construction, we determined the genes whose expression is influenced by these transcription factors, and the pathways in which they are involved. We found that LEF1 and TCF3 are over-expressed in breast tumors regarding non-tumor samples, while TCF4 and TCF7 are down-expressed, with the gene's methylation status being associated with its expression dysregulation. All four transcription factors presented significance at the diagnostic and prognostic levels. LEF1, TCF4, and TCF7 presented a significant correlation with immune cell infiltration, being associated with the immune subtypes of less favorable outcomes. Altogether, this research contributes to a more accurate understanding of the expression and clinical and biomarker significance of the LEF1/TCF transcription factors in breast cancer.

6.
Int J Mol Sci ; 23(15)2022 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-35897709

RESUMEN

Herpes simplex virus type-1 (HSV-1) infection causes several disorders, and acyclovir is used as a reference compound. However, resistant strains are commonly observed. Herein, we investigate the effects of N-heterocyclic compounds (pyrazolopyridine derivatives), named ARA-04, ARA-05, and AM-57, on HSV-1 in vitro replication. We show that the 50% effective concentration (EC50) values of the compounds ARA-04, ARA-05, and AM-57 were 1.00 ± 0.10, 1.00 ± 0.05, and 0.70 ± 0.10 µM, respectively. These compounds presented high 50% cytotoxic concentration (CC50) values, which resulted in a selective index (SI) of 1000, 1000, and 857.1 for ARA-04, ARA-05, and AM-57, respectively. To gain insight into which step of the HSV-1 replication cycle these molecules would impair, we performed adsorption and penetration inhibition assays and time-of-addition experiments. Our results indicated that ARA-04 and ARA-05 affected viral adsorption, while AM-57 interfered with the virus replication during its α- and γ-phases and decreased ICP27 content during initial and late events of HSV-1 replication. In addition, we also observed that AM-57 caused a strong decrease in viral gD content, which was reinforced by in silico calculations that suggested AM-57 interacts preferentially with the viral complex between a general transcription factor and virion protein (TFIIBc-VP16). In contrast, ARA-04 and ARA-05 interact preferentially in the proteins responsible for the viral adsorption process (nectin-1 and glycoprotein). Thus, our results suggest that the 1H-pyrazolo[3,4-b]pyridine derivatives inhibit the HSV-1 replicative cycle with a novel mechanism of action, and its scaffold can be used as a template for the synthesis of promising new molecules with antiviral effects, including to reinforce the presented data herein for a limited number of molecules.


Asunto(s)
Herpes Simple , Infecciones por Herpesviridae , Herpesvirus Humano 1 , Aciclovir/farmacología , Animales , Antivirales/farmacología , Antivirales/uso terapéutico , Chlorocebus aethiops , Herpes Simple/tratamiento farmacológico , Infecciones por Herpesviridae/tratamiento farmacológico , Herpesvirus Humano 1/fisiología , Pirazoles , Piridinas/farmacología , Piridinas/uso terapéutico , Células Vero , Replicación Viral
7.
Environ Sci Technol ; 55(22): 15149-15161, 2021 11 16.
Artículo en Inglés | MEDLINE | ID: mdl-34726395

RESUMEN

Rough-toothed dolphins, Steno bredanensis, are closely associated with coastal waters in the Southwestern Atlantic Ocean, increasing the exposure to multiple stressors, such as chemical pollution. Persistent organic pollutants (POPs) are known to affect the health of cetacean species. To comprehend the potential impacts of POPs on populations' viability, it is necessary to distinguish populations and predict their risk of long-term exposure. Blubbers of rough-toothed dolphins (n = 28) collected along the southeastern (SE) and southern (S) Brazilian coast were screened for polychlorinated biphenyls (PCBs) and pesticides in a gas chromatograph coupled to a mass spectrometer. Based on the contamination profile, a discriminant function analysis separated the rough-toothed dolphins into three ecological populations: two coastal and one offshore. POP concentrations were the highest reported for the species worldwide and highest among the delphinids in Brazilian waters, reaching 647.9 µg g-1 lw for PCBs. The SE population presented 212.9 ± 163.0, S population presented 101.0 ± 96.7, and OCS/S population presented 183.3 ± 85.3 µg g-1 lw (mean ± SD) of PCBs. The potential risk of effects triggered by elevated PCB concentrations was assessed in an individual-based model. A risk of severe decline in population size is projected for the three populations in the next 100 years, especially in SE Brazil, varying between 67 and 99%.


Asunto(s)
Delfines , Contaminantes Ambientales , Bifenilos Policlorados , Animales , Océano Atlántico , Monitoreo del Ambiente , Bifenilos Policlorados/análisis
8.
Vet Pathol ; 57(6): 845-857, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32964811

RESUMEN

Cetacean morbillivirus (CeMV; Paramyxoviridae) is the most significant pathogen of cetaceans worldwide. The novel "multi-host" Guiana dolphin (Sotalia guianensis; GD)-CeMV strain is reported in South American waters and infects Guiana dolphins and southern right whales (Eubalaena australis). This study aimed to describe the pathologic findings, GD-CeMV viral antigen distribution and detection by RT-PCR (reverse transcriptase polymerase chain reaction), and infectious comorbidities in 29 Guiana dolphins that succumbed during an unusual mass-mortality event in Rio de Janeiro state, Brazil, between November 2017 and March 2018. The main gross findings were lack of ingesta, pulmonary edema, ascites, icterus, hepatic lipidosis, multicentric lymphadenomegaly, as well as pneumonia, polyserositis, and multiorgan vasculitis caused by Halocercus brasiliensis. Microscopically, the primary lesions were bronchointerstitial pneumonia and multicentric lymphoid depletion. The severity and extent of the lesions paralleled the distribution and intensity of morbilliviral antigen. For the first time in cetaceans, morbilliviral antigen was detected in salivary gland, optic nerve, heart, diaphragm, parietal and visceral epithelium of glomeruli, vulva, and thyroid gland. Viral antigen within circulating leukocytes suggested this as a mechanism of dissemination within the host. Comorbidities included disseminated toxoplasmosis, mycosis, ciliated protozoosis, and bacterial disease including brucellosis. These results provide strong evidence for GD-CeMV as the main cause of this unusual mass-mortality event.


Asunto(s)
Delfines , Infecciones por Morbillivirus , Morbillivirus , Animales , Brasil , Delfines/virología , Femenino , Infecciones por Morbillivirus/patología , Infecciones por Morbillivirus/veterinaria
9.
J Acoust Soc Am ; 148(5): EL420, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33261388

RESUMEN

Atlantic spotted dolphins were recorded on the coastal area of Rio de Janeiro with equipment of 192 kHz sampling rate. The animals produced an average of 33 whistles/min. The repertoire was balanced among four contour categories, with the occurrence of a stereotyped whistle. Frequency parameters were measured between 1.3 and 29 kHz, which represents an increase in the frequency range previously reported for this species in the southwestern Atlantic Ocean. With the use of a higher sampling rate, the acoustic parameters of S. frontalis whistles have changed significantly and became more similar to those reported for North Atlantic populations.


Asunto(s)
Delfines , Stenella , Animales , Océano Atlántico , Brasil , Espectrografía del Sonido , Vocalización Animal
10.
ScientificWorldJournal ; 2020: 3727453, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32410905

RESUMEN

INTRODUCTION: In recent decades, there has been an intensification of environmental problems, which are becoming increasingly critical and frequent due to population growth. Microorganisms, including soilborne fungi, play an essential role in maintaining and balancing the environment. One of the most impacted ecosystems in São Luís, Maranhão, Brazil, is the Jansen Lagoon State Park, an important tourist spot, which has suffered anthropogenic actions such as the dumping of household waste (sewage) in its body of water. As a consequence, these pollutants can accumulate in the adjacent soil, since the body of water is near this substrate. The objectives were to isolate and identify filamentous fungi from the soil of the Jansen Lagoon State Park. METHODS: Monthly soil samples were collected and later processed using the modified suspension technique according to Clark (1965). RESULTS: The isolated genera were Aspergillus, Penicillium, Trichoderma, Absidia, and Fusarium. Aspergillus is the fungal genus of greater dominance in the soil of the Jansen Lagoon State Park. Aspergillus niger was the dominant species (37%), followed by A. tamarii (21.6%). CONCLUSION: The main isolated fungi from the Jansen Lagoon State Park were Aspergillus niger and Aspergillus tamrii. These fungi can be used as biological markers of pollution and as biodegraders and/or bioremediators to improve the area studied.


Asunto(s)
Biodiversidad , Ambiente , Hongos/clasificación , Océanos y Mares , Microbiología del Suelo , Brasil , Geografía
11.
J Acoust Soc Am ; 146(2): EL124, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31472545

RESUMEN

This study aimed to investigate the use of high ultrasonic frequencies (above 40 kHz) in the Sotalia guianensis whistle repertoire. The whistles were classified as high-frequency (HF) whistles and very high-frequency (VHF) whistles. Seven parameters were extracted and a general linear mixed effects model was performed between the total number of whistles and VHF ones. Frequency parameters of HF and VHF whistles were the highest reported for this species so far. However, VHF whistles were rare and occurred in situations of high acoustic activity, which may represent a strategy used by dolphins to deal with higher levels of vocalization rates.

12.
Emerg Infect Dis ; 24(7): 1349-1354, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29912687

RESUMEN

During November-December 2017, a mass die-off of Guiana dolphins (Sotalia guianensis) began in Rio de Janeiro, Brazil. Molecular and pathologic investigations on 20 animals indicated that cetacean morbillivirus played a major role. Our findings increase the knowledge on health and disease aspects of this endangered species.


Asunto(s)
Enfermedades de los Animales/epidemiología , Enfermedades de los Animales/virología , Delfines/virología , Infecciones por Morbillivirus/veterinaria , Morbillivirus , Animales , Brasil/epidemiología , Brotes de Enfermedades , Femenino , Masculino , Filogenia , Densidad de Población , ARN Viral
13.
Dis Aquat Organ ; 130(3): 177-185, 2018 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-30259870

RESUMEN

The poxviruses identified in cetaceans are associated with characteristic tattoo or ring skin lesions. However, little is known regarding the prevalence and progression of these lesions and the molecular characterization of cetacean poxviruses in the Southern Hemisphere. This manuscript describes the progression of poxvirus-like skin lesions in 5 free-ranging Guiana dolphins Sotalia guianensis. Additionally, 151 skin samples from 113 free-ranging cetaceans from Brazil, including 4 animals with tattoo skin lesions, were selected for poxvirus testing. Poxviral DNA polymerase gene PCR amplification was used to detect the virus in ß-actin-positive samples (145/151). DNA topoisomerase I gene PCR was then used in Cetaceanpoxvirus (CePV)-positive cases (n = 2), which were further evaluated by histopathology and electron microscopy. Based on photo-identification, adult Guiana dolphins presented regressing or healed poxvirus-like lesions (2/2), while juveniles presented persistent (2/3) or healed and progressive lesions (1/3). CePV DNA was amplified in a common bottlenose dolphin Tursiops truncatus and in a Guiana dolphin. Intracytoplasmic inclusion bodies and viral particles consistent with poxvirus were identified by histology and electron microscopy, respectively. CePV-specific amino acid motifs were identified through phylogenetic analysis. Our findings corroborate previous studies that suggest the placement of poxviruses from cetaceans within the novel CePV genus. This is the first molecular identification of poxvirus in South American odontocetes.


Asunto(s)
Delfín Mular , Filogenia , Infecciones por Poxviridae , Poxviridae , Animales , Delfín Mular/virología , Brasil , Poxviridae/aislamiento & purificación , Infecciones por Poxviridae/veterinaria
14.
Environ Sci Technol ; 51(3): 1176-1185, 2017 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-28055195

RESUMEN

To catalog the diversity and abundance of halogenated organic compounds (HOCs) accumulating in high trophic marine species from the southwestern Atlantic Ocean, tissue from bottlenose dolphins (Tursiops truncatus) stranded or incidentally captured along the coast of Rio de Janeiro, Brazil, were analyzed by a nontargeted approach based on GC×GC/TOF-MS. A total of 158 individual HOCs from 32 different structural classes were detected in the blubber of 4 adult male T. truncatus. Nearly 90% of the detected compounds are not routinely monitored in the environment. DDT-related and mirex/dechlorane-related compounds were the most abundant classes of anthropogenic origin. Methoxy-brominated diphenyl ethers (MeO-BDEs) and chlorinated methyl- and dimethyl bipyrroles (MBPs and DMBPs) were the most abundant natural products. Reported for the first time in southwestern Atlantic cetaceans and in contrast to North American marine mammals, chlorinated MBPs and DMBPs were more abundant than their brominated and/or mixed halogenated counterparts. HOC profiles in coastal T. truncatus from Brazil and California revealed a distinct difference, with a higher abundance of MeO-BDEs, mirex/dechloranes and chlorinated bipyrroles in the Brazilian dolphins. Thirty-six percent of the detected HOCs had an unknown structure. These results suggest broad geographical differences in the patterns of bioaccumulative chemicals found in the marine environment and indicate the need to develop more complete catalogs of HOCs from various marine environments.


Asunto(s)
Delfín Mular , Monitoreo del Ambiente , Animales , Brasil , Delfines , Compuestos Orgánicos , Contaminantes Químicos del Agua
15.
J Acoust Soc Am ; 141(4): 2947, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28464652

RESUMEN

Acoustic studies of Guiana dolphin have been focused on whistles, with little known about pulse signals in this species. This study characterized the temporal and spectral properties of Guiana dolphin burst pulses. Groups of 2 to 23 Guiana dolphins were recorded while feeding and socializing in shallow waters in Guanabara Bay, southeastern Brazil, in 2013 and 2014. Burst pulse analysis involved two steps: signal detection and acoustic parameter analysis. Eight variables were analyzed for 197 total burst pulses: number of clicks, burst pulse duration, interclick interval, click duration, peak frequency, center frequency, -3 dB bandwidth, and -10 dB bandwidth. Mean burst pulse duration was 108.6 ms [standard deviation (SD) = 91.3] with a mean of 168 clicks (SD = 137.3). Burst pulses had short interclick interval (0.7 ms, SD = 0.3) and mean click duration of 300 µs (SD = 100). Mean peak frequency and center frequency were 28 kHz (SD = 11.6) and 29 kHz (SD = 11.0), respectively. Mean -3 dB bandwidth was 15 kHz (SD = 7.5) and mean -10 dB bandwidth was 40.5 kHz (SD = 14.3). The quantitative characterization of Guiana dolphin burst pulses is an important step in describing the full acoustic repertoire of this species.


Asunto(s)
Acústica , Delfines/psicología , Monitoreo del Ambiente/métodos , Vocalización Animal , Animales , Brasil , Delfines/clasificación , Procesamiento de Señales Asistido por Computador , Espectrografía del Sonido , Factores de Tiempo , Vocalización Animal/clasificación
16.
J Acoust Soc Am ; 139(5): EL124, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-27250196

RESUMEN

The present study evaluates variations in frequency and duration parameters of whistles of four dolphin species (Sotalia guianensis, Steno bredanensis, Stenella frontalis, and Tursiops truncatus), recorded in the Rio de Janeiro State Coast, Southeastern Brazil. A total of 487 whistles were analyzed. Acoustic parameters of the whistles were classified to species by discriminant function analysis. Overall classification score was 72.5%, with the highest classification score obtained for whistles of S. bredanensis and the lowest obtained for S. frontalis. Most differences were among S. bredanensis and S. guianensis, species that did not have their repertoires compared in other studies.


Asunto(s)
Delfines/fisiología , Vocalización Animal , Acústica , Animales , Delfín Mular/clasificación , Delfín Mular/fisiología , Brasil , Análisis Discriminante , Delfines/clasificación , Análisis de Fourier , Especificidad de la Especie , Stenella/clasificación , Stenella/fisiología , Vocalización Animal/clasificación
17.
Arch Environ Contam Toxicol ; 71(3): 336-46, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27430575

RESUMEN

Guiana dolphin is the top predator of highest toxicological concern in Brazil and many studies on levels of persistent, bioaccumulative, and toxicant (PBT) pollutants have been performed on the species. However, due to high costs of the analyses, only one investigation comprised the determination of dioxins and related compounds (DRCs) in Guiana dolphin tissues. The dioxin responsive-chemically activated luciferase gene expression (DR-CALUX(®)) cell bioassay was used in the present study for the analyses of hepatic samples from 28 male Guiana dolphins in order to screen estuarine environments for DRCs, comprising three regions (Northeastern, Southeastern, and Southern) and four states [Paraná (PR), Rio de Janeiro (RJ), Espírito Santo (ES), and Ceará (CE)] of Brazil. High bioanalytical equivalent (BEQ) concentrations [dioxins (pg BEQ/g lipid)] were found, varying from 1.94 to 15.6 pg BEQ/g. A significant negative correlation between BEQ concentrations and total length was found in Guiana dolphins from Brazil (all analysed dolphins). This pattern also was verified for RJ state, pointing to (1) chemically induced developmental disruption or to (2) increasing efficiency of the detoxifying activity with the growth of the animal. Comparison was performed with literature data and significantly higher BEQ levels were found in Brazilian Guiana dolphins than in those reported for North Sea harbour porpoises. Higher levels were found in Southeastern (the most PBT-contaminated area of the country) than in Southern region. However, it is not possible to affirm that Guiana dolphins are more contaminated by DRCs in SE than in S region, because individuals were lengthier in S than in SE region. Our results seem to have mirrored dolphin exposure to PCBs in Brazil according to the literature. Further studies are required for investigating the hypotheses 1 and 2 mentioned above.


Asunto(s)
Dioxinas/metabolismo , Delfines/metabolismo , Monitoreo del Ambiente/métodos , Contaminantes Químicos del Agua/metabolismo , Animales , Bioensayo , Brasil , Masculino
18.
Environ Res ; 138: 49-57, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25688003

RESUMEN

The study documents the levels and profiles of selected contaminants [polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), polybrominated diphenyl ethers (PBDEs) and methoxylated PBDEs (MeO-PBDEs)] in blubber biopsy samples collected from humpback whales (Megaptera novaeangliae) in Antarctic Peninsula waters. In addition, we investigated year-to-year and sex-related differences in the bioaccumulation patterns. Except for hexachlorobenzene (HCB), whose concentrations were in the same range as those found in whales from the Northern Hemisphere, levels of all other compounds were lower in Southern Hemisphere whales compared to literature data on animals from the Arctic and subarctic region. The mean contribution to the sum of all anthropogenic organohalogen compounds (ΣOHC) decreased in the following order ΣPCBs (44%)>HCB (31%)>ΣDDXs (13%)>ΣCHLs (4.6%)>ΣHCHs (4.4%)>ΣPBDEs (0.9%). The predominant compounds within each chemical class were: PCBs 153, 149, 101 and 138; p,p'-DDE; γ-HCH; trans-nonachlor; PBDEs 99 and 47. The most dominant MeO-PBDE congener was 6-MeO-BDE 47. As samples were collected during three consecutive summer seasons, year-to-year trends could be assessed indicating a significant decrease from 2000 to 2003 for ΣCHL levels. Higher ΣPBDE concentrations and higher values of the ΣPBDE / ΣMeO-PBDE ratio, as well as higher ratios between the two MeO-BDEs (2'-MeO-BDE 68/6-MeO-BDE 47) were found in females compared to males. Higher ΣMeO-PBDE concentrations and higher values of the ratios between the lower chlorinated and the higher chlorinated PCBs were found in males than in females. In addition, five out of six significant differences found through discriminant function analysis were gender-related. The literature reports both feeding in mid- to low-latitudes and sex-related differences in migration patterns for humpback whales from the Southern Hemisphere, indicating that the hypothesis of dietary differences between males and females cannot be excluded. Nevertheless, additional studies are required for further investigation of this hypothesis.


Asunto(s)
Exposición a Riesgos Ambientales , Éteres Difenilos Halogenados/análisis , Yubarta/metabolismo , Insecticidas/análisis , Bifenilos Policlorados/análisis , Contaminantes Químicos del Agua/análisis , Animales , Regiones Antárticas , Monitoreo del Ambiente , Femenino , Éteres Difenilos Halogenados/metabolismo , Insecticidas/metabolismo , Masculino , Bifenilos Policlorados/metabolismo , Contaminantes Químicos del Agua/metabolismo
19.
J Acoust Soc Am ; 137(1): EL15-9, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25618093

RESUMEN

Guiana dolphins produce whistles with a higher frequency and less complexity than most other delphinid species. The present study used a recording system with sampling rate of 192 kHz to describe the high-frequency whistles of Sotalia guianensis in Guanabara Bay, Rio de Janeiro. Eleven acoustic parameters (start, end, minimum, maximum, delta, center and peak frequency, duration, and frequency at 14, 12, and 34 of duration) were measured for all whistles. Whistles with a fundamental frequency up to 66.7 kHz were reported, thereby expanding the known frequency range of this species.


Asunto(s)
Delfines/fisiología , Ondas Ultrasónicas , Vocalización Animal/fisiología , Animales , Brasil , Espectrografía del Sonido , Especificidad de la Especie , Transductores
20.
Artículo en Inglés | MEDLINE | ID: mdl-26513931

RESUMEN

Nosocomial infections are one of the leading causes of morbidity and mortality. This study determined both prevalence and antimicrobial susceptibility of microorganisms identified during January to December 2012 at a tertiary public hospital, Sao Paulo, Brazil. Data, hospital length of stay, age, identity of microorganisms, and antimicrobial susceptibilities were obtained from patients' records. A total of 724 positive strains were obtained from different body sites. Gram-negative microorganisms are significantly more prevalent than gram-positive microorganisms (p = 0.001). In all clinics analyzed, coagulase-negative Staphylococcus (CoNS) was the most prevalent microorganism isolated (21.6%), followed by Pseudomonas aeruginosa (12.4%). Extended spectrum ß-lactamase Klebsiella pneumoniae was present in 62.7% of the strains and 18.9% were resistant to carbapenem/meropenem. Acinetobacter baumannii showed multidrug resistance. The majority of Escherichia coli isolates were obtained from positive urinary tract cultures (63.4%), with 27.5% resistant against cefepime. Elderly patients, long periods of hospital stay and continuous usage of a single antibiotic should be kept in mind of possible causes for infection of A. baumannii, ESBL and carbapenem-resistant K. pneumoniae and the worrisome E. coli with increased resistance to cefepime. The data allowed us to implement monitoring programs as part of the prevention strategy against pathogens prevalence and antibiotic resistance burden at Ipiranga Hospital, Sao Paulo, Brazil.


Asunto(s)
Antibacterianos , Infecciones Bacterianas/epidemiología , Infección Hospitalaria/epidemiología , Farmacorresistencia Bacteriana , Hospitales Públicos , Centros de Atención Terciaria , Infecciones por Acinetobacter/epidemiología , Infecciones por Acinetobacter/microbiología , Acinetobacter baumannii/aislamiento & purificación , Acinetobacter baumannii/fisiología , Infecciones Bacterianas/microbiología , Brasil/epidemiología , Estudios de Cohortes , Infección Hospitalaria/microbiología , Enterococcus/aislamiento & purificación , Enterococcus/fisiología , Escherichia coli/aislamiento & purificación , Escherichia coli/fisiología , Infecciones por Escherichia coli/epidemiología , Infecciones por Escherichia coli/microbiología , Humanos , Infecciones por Klebsiella/epidemiología , Infecciones por Klebsiella/microbiología , Klebsiella pneumoniae/aislamiento & purificación , Klebsiella pneumoniae/fisiología , Pruebas de Sensibilidad Microbiana , Infecciones por Pseudomonas/epidemiología , Infecciones por Pseudomonas/microbiología , Pseudomonas aeruginosa/aislamiento & purificación , Pseudomonas aeruginosa/fisiología , Estudios Retrospectivos , Infecciones Estafilocócicas/epidemiología , Infecciones Estafilocócicas/microbiología , Staphylococcus/aislamiento & purificación , Staphylococcus/fisiología
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