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1.
Artigo em Inglês | MEDLINE | ID: mdl-33694119

RESUMO

The toxicity of copper, cadmium, and dieldrin in adult Gammarus locusta (a marine amphipod) is currently unclear. Thus, G. locusta from the North Lake of Tunis were subjected to acute toxicity tests to assess LC50s at 48-96 h and to biomarker response tests through the assessment of catalase and acetylcholinesterase activities and malondialdehyde levels. The present study demonstrated the abilities of a chlorinated hydrocarbon pesticide (dieldrin) induce to oxidative stress and neurotoxicity. The comparison of metal toxicity showed that G. locusta was more sensitive to cadmium than copper. The three stressors caused significant inductions of all three biomarkers in a concentration-dependent manner. Catalase induction was dependent on exposure duration for all pollutants, while only copper led to increased malondialdehyde with longer exposure times. Catalase induction and malondialdehyde increase appeared to be sex dependent for all three pollutants. The neurotoxic effects of the pollutants were concentration dependent according to inhibition of acetylcholinesterase activity. In conclusion, catalase, malondialdehyde, and acetylcholinesterase are efficient biomarkers of copper, cadmium, and dieldrin in G. locusta.

2.
Artigo em Inglês | MEDLINE | ID: mdl-33560507

RESUMO

Numerous studies have focused on the response of meiofauna after exposure to polycyclic aromatic hydrocarbons (PAHs), but none has been devoted to their uptake into nematode body compartments. The present study monitored PAH uptake by Oncholaimus campylocercoides which was selected after 40 days in the laboratory through original protocols from natural sediments collected in the Old Harbor of Bizerte, Tunisia. To achieve the mono-species level, a grain size magnification was applied by gradually adding a biosubstrate made from either the crushed shells of Mytilus galloprovincialis or minced leaves of Posidonia oceanica. After selection, O. campylocercoides was cultured and fed with earthworm powder (560 mg.l-1). Thereafter, it was exposed for 3 weeks to phenanthrene and chrysene (38, 116, and 348 ppb). Fluorescence microscopy revealed higher intensities of PAHs at the spicules, mouths, and pharynges compared with the other organs considered. Moreover, the buccal fluorescence showed a significant correlation with that measured in the biosubstrate made with shells of M. galloprovincialis.

3.
Environ Sci Pollut Res Int ; 28(17): 21303-21313, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33411276

RESUMO

In this study, a microcosm experiment was conducted for 30 days to assess the impact of the presence of juvenile gray shrimp Crangon crangon on meiofauna. The results suggested that juvenile shrimp had a significant negative impact on the abundance of nematodes and copepods, but no effect on polychaetes. Moreover, nematodes showed a significant decline in individual weight. The collected nematodes were taxonomically identified and assigned to five functional traits: shapes of the tail and amphid, life history, feeding types, and adult length. The nematode traits were affected by the number of shrimp introduced, and descriptors followed normal or inversed bell-shaped curves. When no shrimp were present, the nematofauna had a higher species richness compared with treatments of 4, 8, and 12 shrimp. Bell-shaped curve patterns were common in relation to the two phases of feeding for C. crangon. During the first phase, C. crangon consumed the nematode species Oncholaimus campylocercoides; thereafter, shrimp fed mostly on the nematode Anticoma eberthi and copepods.

4.
Artigo em Inglês | MEDLINE | ID: mdl-33010015

RESUMO

Meiobenthic nematodes are well-known bioindicators in aquatic ecosystem health programs. However, the explored taxa are still limited and practically devoted to the community level. The present study provided a new method of experimental isolation of a species from a pristine nematofauna. In our method, the nematofauna faced two types of sediment, namely, the leaves of Posidonia oceanica and shells of Mytilus galloprovincialis, under controlled laboratory conditions, and several changes in species composition occurred through gradual selection of the most adaptable nematode taxa to the new environments, which were previously defaunated. We used the selected nematode taxon, Marylynnia puncticaudata (Cyatholaimidae), to examine the possible effects of organic enrichment, and the results clearly showed that the body size of the nematodes significantly increased and they became fat when after enrichment using a powder made of marine agar (1200 mg l-1) and cuticles of Crangon crangon (900 mg l-1), but their relative body growth showed no discernible changes.

5.
Parasitol Res ; 119(11): 3793-3801, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32979103

RESUMO

Hepatozoon species are the most widely known haemogregarines infecting a wide range of vertebrates, although predominately snakes. Herein, Hepatozoon bashtari n. sp., originally infecting the painted saw-scaled viper, Echis coloratus, in Saudi Arabia is described using both morphological features and molecular data from 18S rDNA sequences. The overall prevalence of infection was 60% (9/15) with parasitaemia ranging from 52 to 60%. Gamonts were entirely intraerythrocytic and were observed to cause considerable hypertrophy within the host cell. The mean size of mature gamonts was 15.4 × 3.3 µm. Merogonic stages were confined to the lung endothelial cells with monomorphic meronts. The average size of mature meronts was 32 × 12 µm and they were estimated to produce 13-16 merozoites each. The phylogenetic tree generated from SSU rDNA sequences revealed that Hepatozoon bashtari sp. n. clusters with the vast majority of other Hepatozoon species infecting snakes, lizards and geckos in various regions of the world, which would appear to support the hypothesis of prey-predator transmission of the genus Hepatozoon. Through a combination of morphological comparison with closely related Hepatozoon spp. and 18S rRNA gene sequence analysis, it is possible to confirm Hepatozoon bashtari sp. n. as a new species.

6.
Mar Pollut Bull ; 160: 111625, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32905910

RESUMO

Compared to open sea environments, there is still limited knowledge about microplastic levels in semi-enclosed systems such as coastal lagoons. This work aims to assess the levels of MPs in the waters of an urban lagoon (Bizerte lagoon, northern Tunisia) and to study the effects of environmental factors on their distribution and abundance. Average concentration of total MPs was found to be 453.0 ± 335.2 items m-3. The upper 25 cm water layer of the lagoon is most likely to contain ~16.99 × 109 MPs items (which correspond to a total mass of 42.47 t). Fibers were the primary MPs types encountered, and most of MPs particles identified were white and clear-colored. Polyethylene and polypropylene were the predominant polymer types in Bizerte lagoon. Among the various potential plastic sources of MPs, unmanaged domestic plastic wastes are likely to be the major source of plastic pollution in the lagoon. Several environmental factors appeared to influence the distribution and density of MPs in the lagoon waters. These information contribute to better understand the dynamics of MPs in lagoons and to develop environmental management actions.


Assuntos
Plásticos , Poluentes Químicos da Água , Monitoramento Ambiental , Mar Mediterrâneo , Microplásticos , Tunísia , Poluentes Químicos da Água/análise
7.
Sci Rep ; 10(1): 15110, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32934328

RESUMO

3-Monochloropropane-1,2-diol (3-MCPD) esters and glycidyl esters (GE) are heat-induced contaminants which form during oil refining process, particularly at the high temperature deodorization stage. It is worth to investigate the content of 3-MCPD and GE in fries which also involved high temperature. The content of 3-MCPD esters and GE were monitored in fries. The factors that been chosen were temperature and duration of frying, and different concentration of salt (NaCl). The results in our study showed that the effect was in the order of concentration of sodium chloride < frying duration < frying temperature. The content of 3-MCPD esters was significantly increased whereas GE was significantly decreased, when prolong the frying duration. A high temperature results in a high 3-MCPD ester level but a low GE level in fries. The present of salt had contributed significant influence to the generation of 3-MCPD. The soaking of potato chips in salt showed no significant effect on the level of GE during the frying. The oil oxidation tests showed that all the fries were below the safety limit. Hence, the frying cycle, temperature and the added salt to carbohydrate-based food during frying should be monitored.

8.
Int J Biometeorol ; 64(12): 1995-2005, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32794023

RESUMO

This study aimed to determine the influence of intermittent hypoxia and the days required for a worker to be acclimatized in high-altitude countries. We conducted an experimental study. Ten nonsmoking male students were randomly recruited from King Saud University. Fourteen days of exposure to intermittent normobaric hypoxia (15%) was the independent variable. Heart rate (HR), respiratory frequency (RF), minute ventilation (VE), respiratory exchange ratio (RER), tidal volume (VT), oxygen uptake (VO2),VO2/kg, VO2/HR, VE/VO2, and VE/VCO2 were the dependent variables. Our results showed that 12 days of exposure to intermittent hypoxia were sufficient for workers to acclimatize to hypoxia based on their respiratory responses (i.e., HR, RF, VE). This type of acclimatization session is very important for workers who are suddenly required to work in such an environment, because prolonged exposure to high altitude without acclimatization leads to cell death due to a lack of oxygen, and this, in turn, puts workers' lives at risk.


Assuntos
Hipóxia , Consumo de Oxigênio , Frequência Cardíaca , Humanos , Masculino , Taxa Respiratória , Volume de Ventilação Pulmonar
9.
Mar Pollut Bull ; 158: 111355, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32753169

RESUMO

This study assesses the microplastics (MPs) levels in mussels (Mytilus galloprovincialis) and seawater from a southern Mediterranean lagoon (Bizerte lagoon, Northern Tunisia) and discusses the potential effects of its consumption on human health. Polyethylene was the most abundant in mussels and seawater, followed by polypropylene and cellophane. The lowest and highest average MPs concentrations were recorded in the lagoon channel and southern area of the lagoon, respectively, for both mussels (2.6 ± 1.7-12.0 ± 1.4 items mussel-1) and seawater (0.2 ± 0.1-0.7 ± 0.2 items L-1). Mussels in areas highly polluted with fibers and polyethylene were found to have higher potential to ingest and/or adhere higher numbers of these particles. The annual dietary intake of MPs by Tunisians through the consumption of local mussels was estimated at 4.2 items capita-1 year-1. Even though MPs are not biodegraded and can be excreted by humans, their potential human health risks are discussed in this paper.


Assuntos
Mytilus , Poluentes Químicos da Água/análise , Animais , Conservação dos Recursos Naturais , Monitoramento Ambiental , Humanos , Microplásticos , Plásticos , Alimentos Marinhos/análise , Água do Mar , Tunísia
10.
Environ Pollut ; 266(Pt 1): 115263, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32768926

RESUMO

A microcosm experiment was carried out to study the ecotoxicity and interactions between heavy metals and polyvinyl chloride microplastics. Fifteen treatments were tested and results were examined after one month. In details, this work aims to study the ecotoxicological effects of cadmium (10 and 20 mg kg-1 Dry Weight DW), polyvinyl chloride (PVC) and its modified forms; PVC-DETA (PD) and PVC-TETA (PT) (20 and 40 mg kg-1 DW), separately and in mixtures, on meiofauna from Bizerte lagoon (NE Tunisia) with focus on nematode features. The results obtained showed that individual treatments were toxic for meiofauna and particularly for free-living nematodes. No clear trends characterized the numerical responses but significant reductions were observed for diversity indices. Moreover, the binary combinations of contaminants have a lesser toxic effect compared to their individual effects. This effect could be related to the high-capacity chelating ability of PVC and its polymers against cadmium.


Assuntos
Cádmio , Cloreto de Polivinila , Animais , Microplásticos , Plásticos , Tunísia
11.
Foods ; 9(7)2020 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-32635372

RESUMO

The present study focused on investigating the storage stability of oil-in-water (O/W) emulsions with high oil volume fractions prepared with palm olein-based diacylglycerol oil (POL-DAG)/soybean oil (SBO) blends at 25 °C. The incorporation of different ratios of oil blends significantly influenced (p < 0.05) the texture, color, droplet size distribution, and rheological parameters of the emulsions. Only emulsions incorporated with 10% to 20% POL-DAG in oil phase exhibited pseudoplastic behavior that fitted the Power Law model well. Furthermore, the O/W emulsions prepared with POL-DAG/SBO blends exhibited elastic properties, with G' higher than G". During storage, the emulsion was found to be less solid-like with the increase in tan δ values. All emulsions produced with POL-DAG/SBO blends also showed thixotropic behavior. Optical microscopy revealed that the POL-DAG incorporation above 40% caused aggregated droplets to coalesce and flocculate and, thus, larger droplet sizes were observed. The current results demonstrated that the 20% POL-DAG substituted emulsion was more stable than the control emulsion. The valuable insights gained from this study would be able to generate a lot more possible applications using POL-DAG, which could further sustain the competitiveness of the palm oil industry.

12.
Bioorg Chem ; 102: 104093, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32717693

RESUMO

Previously phytochemical investigations carried out on the flowers and trunk bark extracts of Citharexylum spinosum L. tree, allowed the isolation of twenty molecules belonging to several families of natural substances [triterpene acids, iridoid glycosides, phenylethanoid glycosides, 8,3'-neolignan glycosides, together with other phenolic compounds]. In the present work, a biological evaluation (anti-tyrosinase, anticholinesterase and cytotoxic activities) was performed on the prepared extracts and the isolated secondary metabolites. The results showed that the EtOAc extract of the trunk bark displayed the highest anti-tyrosinase effect with a percent inhibition of 55.0 ± 1.8% at a concentration of 100 µg/mL. The highest anticholinesterase activity was presented by the same extract with an IC50 value of 99.97 ± 3.01 µg/mL. The EtOAc extract of flowers and that of the trunk bark displayed the best cytotoxic property with IC50 values of 96.00 ± 2.85 and 88.75 ± 2.00 µg/mL, respectively, against the human cervical cancer cell line (HeLa), and IC50 values of 188.23 ± 3.88 and 197.00 ± 4.25 µg/mL, respectively, against the human lung cancer (A549) cell lines. Biological investigation of the pure compounds showed that the two 8,3'-neolignan glycosides, plucheosides D1-D2, generate the highest anti-tyrosinase potency with a percent inhibition of 61.4 ± 2.0 and 79.5 ± 2.3%, respectively, at a concentration of 100 µM. The iridoid glycosides exhibited a significant anticholinesterase activity with IC50 values ranging from 17.19 ± 1.02 to 52.24 ± 2.50 µM. Triterpene pentacyclic acids and iridoid glycosides exerted encouraging cytotoxic effects against HeLa with IC50 values ranging from 9.00 ± 1.10 to 25.00 ± 1.00 µM. The study of the structure-activity relationship (SAR) has been sufficiently and widely discussed. The natural compounds that exhibited the significant bioactivities were docked.

13.
Mar Pollut Bull ; 157: 111375, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32658716

RESUMO

At the end of March 2020, ivermectin was confirmed as a drug for COVID-19 treatment. A significant amount of ivermectin could deposit into sediments of the semi-closed Mediterranean Sea, where three European COVID-19 epicenters are located: Italy, Spain, and France. Meiobenthic nematodes were exposed to three ivermectin doses (1.8 ng.g-1, 9 ng.g-1, and 18 ng.g-1) for 10 days. Ivermectin caused a great reduction in abundance. However, the diversity indices decreased only at high doses. Ivermectin disadvantaged the 1B-Cr-Id functional type (non-selective deposit feeders and nematodes with circular or indistinct amphids) and benefited the 2A-REL-Sp type (epistrate feeders and nematodes with rounded or elongated loop amphids). Thus, Trophic Diversity and Amphideal Diversity index values increased with sedimentary ivermectin enrichment. Large amphideal foveas were more efficient for 2A-REL-Sp nematodes to avoid ivermectin. The responses of the functional type 2A-REL-Sp and corresponding taxa predict post-COVID-19 environmental concerns and the bioaccumulation of ivermectin in seafoods.


Assuntos
Antivirais/toxicidade , Infecções por Coronavirus , Ivermectina , Nematoides , Pandemias , Pneumonia Viral , Animais , Betacoronavirus , Infecções por Coronavirus/tratamento farmacológico , França , Humanos , Itália , Ivermectina/toxicidade , Mar Mediterrâneo , Espanha
14.
Rev Bras Parasitol Vet ; 29(2): e002420, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32428179

RESUMO

Hepatozoon pyramidumi sp. n. is described from the blood of the Egyptian saw-scaled viper, Echis pyramidum, captured from Saudi Arabia. Five out of ten viper specimens examined (50%) were found infected with Hepatozoon pyramidumi sp. n. with parasitaemia level ranged from 20-30%. The infection was restricted only to the erythrocytes. Two morphologically different forms of intraerythrocytic stages were observed; small and mature gamonts. The small ganomt with average size of 10.7 × 3.5 µm. Mature gamont was sausage-shaped with recurved poles measuring 16.3 × 4.2 µm in average size. Infected erythrocytes were hypertrophied; their nuclei were deformed and sometimes displaced from their central position in the normal uninfected cell. Merogonic stages were observed in the lung endothelial cell and the liver parenchyma cells. Mature meront was 17.8 × 13.6 µm and contained banana-shaped merozoites with average size of ~15 × 2 µm. Phylogenetic analysis based on the SSU rDNA sequence clustered Hepatozoon pyramidumi sp. n with previously sequenced Hepatozoon spp., most of them infected reptilian hosts without geographic consideration. The morphological and molecular comparison with closely related species proved the taxonomic uniqueness and novelty of the present form.


Assuntos
Apicomplexa/genética , Apicomplexa/fisiologia , DNA de Protozoário/genética , Viperidae/parasitologia , Animais , Apicomplexa/classificação , DNA Ribossômico/genética , Eritrócitos/parasitologia , Eritrócitos/patologia , Fígado/parasitologia , Fígado/patologia , Pulmão/parasitologia , Pulmão/patologia , Parasitemia/parasitologia , Parasitemia/veterinária , Filogenia , Arábia Saudita , Análise de Sequência de DNA , Viperidae/sangue
15.
Dis Markers ; 2020: 6076274, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32454906

RESUMO

Recurrent spontaneous abortion (RSA) is a common pregnancy-associated complication of polycystic ovary syndrome (PCOS) which is an endocrine malfunction disease. Patients with PCOS may have several underlying contributing and interrelated factors, which have been reported in women with RSA. The incidence rate between PCOS and RSA remains uncertain. The aim of this study is to determine the possible association of IL-1ß-511C/T, IL-6-174G/C, TNF-α-1031T/C, and TGFß1-509T/C with RSA patients with or without PCOS. A total of 140 RSA patients, 70 of which were PCOS patients, and 140 healthy females with no history of RSA or PCOS were included in this study. PCR amplification, genotyping, and sequence analysis were employed to investigate the presence of the polymorphisms. The genotypic and allelic frequencies were calculated separately for each subject. Out of the four studied polymorphisms, the IL-1ß-511C/T genotype in RSA without PCOS patients (12.7%) was significantly different compared with that in control subjects (p = 0.047). For IL-6-174C/G, there was a tendency towards more CC carriers among RSA with PCOS patients (10%) than in controls (3%). The GG genotype in RSA women with PCOS (60%) was significantly different compared with that in control subjects (p = 0.033), and the GC genotype in RSA with PCOS patients (30%) showed a marginal significant difference compared with that in control subjects (p = 0.050). Significant difference was identified in the allelic frequencies in RSA patients with PCOS compared to controls (p = 0.025). IL-6-174G/C and TNF-α-1031T/C polymorphisms are significantly associated with RSA patients in Saudi patients with PCOS, while the IL-1ß-511C/T polymorphism is significantly associated with RSA patients without PCOS.

16.
Environ Pollut ; 263(Pt B): 114529, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32283405

RESUMO

Meiobenthic nematodes have been designated as sensitive global models in the development of biomonitoring and ecotoxicology monitoring programs howbeit the sensitivity of these organisms against oxidative stress biomarkers have never been addressed. The present study aimed to decipher this research axis after selecting and culturing a single nematode species from an entire community through original laboratory protocols. The purpose of this investigation was to change the grain size of the sediment into the immediate environment of nematodes by progressively adding a biosubstrate made from Sepia officinalis endoskeletton. At the end of the experiment, Metoncholaimus pristiurus became the unique component of the nematode species when the sediment was enriched with 80% of S. officinalis powder. After the mono-species level had been achieved, the selected species was fed on an another biosubstrate made from bodies of Porcellio scaber under the identical laboratory controlled conditions of light and temperature adopted during the selection process. Accordingly, the bioassay protocol this study layed new foundations for the study of meiobenthic nematodes in the biomarker field. Our results revealed that, in case of M. pritiurus, discernible oxidative stress responses are valid for catalase and gluthatione S-transferase. Indeed, for both enzymes, a clear increase in the activity was recorded, and the response was more reinforced when zinc and permethrin were administrated in combination. The relevance of the protocols proposed in this work parallels their global applicability to reach and maintain the monospecific level in laboratory by using biosubstrates made from animals widely distributed. It is true also that our data provided the first results in terms of biochemical biomarkers for meiobenthic nematodes and showed that the selected taxa, M. pristiurus, could be one of the first marine taxa responding early to the tested stressors, zinc and permethrin, even at very low concentrations.


Assuntos
Isópodes , Nematoides , Animais , Biomarcadores , Catalase , Monitoramento Ambiental , Estresse Oxidativo
17.
Environ Pollut ; 262: 114350, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32197121

RESUMO

A laboratory bioassay was conducted to investigate the ecotoxicity of a chromium-enriched superfood, Spirulina platensis, on the meiofauna collected from the Ghar El Melh lagoon, Tunisia. After 1 month of exposure, the abundances of meiobenthic taxa and the taxonomic and morpho-functional diversity of nematodes showed significant differences between the Spirulina and Spirulina + chromium groups. The nematodes were more tolerant of all types of stressors compared to harpacticoids, polychaetes, and oligochaetes, and the lowest taxonomic and morpho-functional diversity of nematodes was observed in the highest sedimentary concentration of S. platensis (50% DW). The mixed treatments may have been richer in micro-habitats and subject to low selective pressure, thereby hosting nematodes with a wide range of adaptations. The responses of the nematode species differed depending on their functional traits. Spirulina enriched with chromium induced two responses for the same feeding group: high toxicity for Daptonema fallax and low toxicity for two Theristus species (T. flevensis and T. modicus). The ecotoxicity of the Spirulina/chromium mixtures were lower than that of Spirulina alone, suggesting mutual neutralization between these two elements. The association between functional traits and taxonomic diversity showed that the effects of the mixtures were not additive and that one of the stressors camouflaged the effect of the other. Our findings should encourage the commercialization of chromium-enriched S. platensis owing to its lower ecotoxicity than Spirulina alone.


Assuntos
Nematoides , Spirulina , Animais , Cromo , Ecossistema , Tunísia
18.
Environ Sci Pollut Res Int ; 27(10): 11403-11412, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31965497

RESUMO

Organic enrichment due to human impact is one of the major threats that affect benthic communities in semi-enclosed marine ecosystems, such as the Mediterranean Sea. However, many emerging sources of organic pollutants, such as those released to nature through human practices related to esthetics and cosmetics, remain underestimated, despite being an increasingly important source of organic matter input following a decade of expansion by the cosmetic industry. Therefore, an experiment was designed to explore the influence of collagen, the main component of commercialized skin anti-aging products, on a Mediterranean community of free-living marine nematodes from a beach in Rimel, northeast Tunisia. The effects of exposure for 30 days to a control treatment and three test treatments, corresponding to three levels of sedimentary enrichment with collagen (3, 6, and 12 ppm dry weight (DW)), were examined using a microcosm approach. Reductions in abundance and diversity were noted with an increase in collagen enrichment, together with a slight increase in individual weight. The presence of three species characteristic of control microcosms, Ptycholaimellus ponticus, Theristus modicus, and Kraspedonema reflectans, was clearly affected at the lowest dose; these were therefore classified as "collagen-sensitive." In contrast, the numbers of "collagen-tolerant" species, including Sigmophoranema rufum, Lauratonema hospitum, Enoploides spiculohamatus, and Trichotheristus mirabilis, increased significantly in the treated microcosms.


Assuntos
Sedimentos Geológicos , Nematoides , Animais , Bioensaio , Colágeno , Ecossistema , Humanos , Mar Mediterrâneo , Tunísia
19.
Genet Test Mol Biomarkers ; 24(2): 78-84, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31999488

RESUMO

Aims: This study was designed to determine whether genetic polymorphisms of the killer immunoglobulin-like receptor (KIR) and human leukocyte antigen class I (HLA-C) genes are associated with recurrent spontaneous abortion (RSA) in Saudi women. Materials and Methods: Sixty-five healthy women with a history of RSA (three or more spontaneous abortions) and 65 healthy controls (with two or more healthy-born children) living in Riyadh were typed for 17 KIR genes and the HLA-C1 and HLA-C2 allotypes using polymerase chain reaction-sequence-specific primer methodology. Results: The frequencies of KIR2DS2 and KIR2DL5A were significantly lower among RSA women compared to healthy controls (odds ratio [OR] = 0.17; p < 0.001; OR = 0.16; p < 0.001, respectively). No association with maternal HLA-C genotypes was observed. Analysis of KIR-HLA-C combinations indicated a protective effect of KIR2DS2 with its cognate HLA-C1 ligand in both homozygote or heterozygote combinations. Conclusion: Our results demonstrate that the KIR genes of the B haplotype may play an important role in ensuring the success of pregnancy.


Assuntos
Aborto Habitual , Antígenos HLA-C , Receptores KIR , Aborto Habitual/genética , Aborto Habitual/imunologia , Adolescente , Adulto , Feminino , Antígenos HLA-C/genética , Antígenos HLA-C/imunologia , Humanos , Pessoa de Meia-Idade , Gravidez , Receptores KIR/genética , Receptores KIR/imunologia , Arábia Saudita
20.
Acta Trop ; 204: 105331, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31923380

RESUMO

Glugea eda n. sp. is described from the mesenteries of the striated fusilier, Caesio striata, collected from the Red Sea coast off Yanbu' al Bahr, Saudi Arabia. Numerous blackish xenomas, ranged from 3 to 5 mm, were found in the body cavity associated with the mesenteries. Mature spores are monomorphic, ellipsoidal with an average size of 5(4-6) µm in length and 2.2 (2-3) µm in width. Observations of the ultrastructure revealed that the development was asynchronous and that the nuclei were isolated throughout the life cycle with uninucleate meronts. Sporoblasts were uninucleated and existed together with sporonts in a fully formed parasitophorous vacuole. The polar filament of the mature spore was isofilar with 24-28 coils, arranged in three rows. Phylogenetic analysis placed the current microsporidia within the clade grouping Glugea species and close to the species described from the Red Sea and Arabian Gulf. The morphometric and molecular comparison with other members of the genus Glugea evidenced the taxonomic novelty of the present form, suggesting that it should be considered as a new species. To the best of our knowledge, the parasite here described represents the first occurrence of microsporidian infection in the fish of the family Caesionidae.


Assuntos
Doenças dos Peixes/microbiologia , Peixes , Glugea/isolamento & purificação , Microsporidiose/veterinária , Animais , Doenças dos Peixes/epidemiologia , Oceano Índico , Microsporidiose/epidemiologia , Filogenia , Arábia Saudita
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