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1.
World J Gastroenterol ; 29(3): 561-578, 2023 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-36688020

RESUMO

BACKGROUND: Angiosarcoma is a highly malignant soft-tissue sarcoma derived from vascular endothelial cells that mainly occurs in the skin and subcutaneous tissues. Small-intestinal angiosarcomas are rare, and the prognosis is poor. CASE SUMMARY: We reported a case of primary multifocal ileal angiosarcoma and analyze previously reported cases to improve our understanding of small intestinal angiosarcoma. Small intestinal angiosarcoma is more common in elderly and male patients. Gastrointestinal bleeding, anemia, abdominal pain, weakness, and weight loss were the common symptoms. CD31, CD34, factor VIII-related antigen, ETS-related gene, friend leukemia integration 1, and von Willebrand factor are valuable immunohistochemical markers for the diagnosis of small-intestinal angiosarcoma. Small-intestinal angiosarcoma most commonly occurs in the jejunum, followed by the ileum and duodenum. Radiation and toxicant exposure are risk factors for angiosarcoma. After a definite diagnosis, the mean and median survival time was 8 mo and 3 mo, respectively. Kaplan-Meier survival analysis showed that age, infiltration depth, chemotherapy, and the number of small intestinal segments invaded by tumor lesions were prognostic factors for small intestinal angiosarcoma. Multivariate Cox regression analysis showed that chemotherapy and surgery significantly improved patient prognosis. CONCLUSION: Angiosarcoma should be considered for unexplained melena and abdominal pain, especially in older men and patients with a history of radiation exposure. Prompt treatment, including surgery and adjuvant chemotherapy, is essential to prolonging patient survival.


Assuntos
Hemangiossarcoma , Neoplasias do Jejuno , Humanos , Masculino , Idoso , Hemangiossarcoma/diagnóstico , Hemangiossarcoma/terapia , Hemangiossarcoma/patologia , Células Endoteliais/patologia , Intestino Delgado/patologia , Neoplasias do Jejuno/diagnóstico , Neoplasias do Jejuno/terapia , Neoplasias do Jejuno/patologia , Prognóstico , Fator de von Willebrand
2.
EMBO Mol Med ; 14(5): e14844, 2022 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-35362189

RESUMO

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) can cause gastrointestinal (GI) symptoms that often correlate with the severity of COVID-19. Here, we explored the pathogenesis underlying the intestinal inflammation in COVID-19. Plasma VEGF level was particularly elevated in patients with GI symptoms and significantly correlated with intestinal edema and disease progression. Through an animal model mimicking intestinal inflammation upon stimulation with SARS-CoV-2 spike protein, we further revealed that VEGF was over-produced in the duodenum prior to its ascent in the circulation. Mechanistically, SARS-CoV-2 spike promoted VEGF production through activating the Ras-Raf-MEK-ERK signaling in enterocytes, but not in endothelium, and inducing permeability and inflammation. Blockage of the ERK/VEGF axis was able to rescue vascular permeability and alleviate intestinal inflammation in vivo. These findings provide a mechanistic explanation and therapeutic targets for the GI symptoms of COVID-19.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Enterócitos/metabolismo , Humanos , Inflamação/metabolismo , Glicoproteína da Espícula de Coronavírus , Fator A de Crescimento do Endotélio Vascular
3.
Front Oncol ; 12: 809430, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35359367

RESUMO

Objective: To investigate the correlation between intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI) and the pathological classification of idiopathic orbital inflammatory pseudotumors (IOIPs). Methods: Nineteen patients who were diagnosed with IOIPs (a total of 24 affected eyes) between November 2018 and December 2020 were included in the study. All the patients underwent magnetic resonance imaging orbital plain scans and IVIM-DWI multiparameter scans before an operation. The true diffusion coefficient (D), pseudodiffusion coefficient (D*), and perfusion fraction (f) values were obtained. Based on histopathology, the lesions were divided into three types: lymphocytic infiltration, fibrosclerotic, and mixed. The correlation between IVIM-DWI parameters and pathological classification was tested with the histopathological results as the gold standard. The data were analyzed using SPSS version 17.0, with P < 0.05 defined as significant. Results: Among the 19 patients (24 eyes) affected by IOIP, there were no significant differences between IOIP pathological classification and gender or age (P > 0.05). There were statistically significant differences between the D and f values for different pathological types of IOIP and IVIM parameters (P < 0.05), and there was no significant difference in D* value between the different pathological types (P > 0.05). Conclusion: The D and f values showed correlation with different types of IOIP, and the sensitivity of the D value was higher than that of the f value. The D* value showed no significant distinction between pathological types of IOIP.

4.
Aquat Toxicol ; 224: 105503, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32438217

RESUMO

Tributyltin (TBT) was reported to affect sexual behavior and gametogenesis in fish. However, the modes of action involved are largely unclear. In order to elucidate the toxicological mechanisms of TBT in reproduction, zebrafish (Danio rerio) males were exposed to TBT at concentrations of 100 and 500 ng/L for 28 days. After exposure, the sperm count of the treated fish was sharply decreased though the testis weight and gonadosomatic index remained unchanged. Moreover, reduced number of spermatogonia and spermatozoa and increased spermatocytes were observed in TBT-treated fish by histological observation and PCNA-immunostaining. Increased number of apoptotic-positive spermatocytes was also present in TBT-treated fish, indicating an enhanced apoptosis in these cells. Consistent to decreased number of spermatogonia, down-regulated expressions of genes responsible for germ cell proliferation (cyclind1 and pcna) were observed in TBT-treated fish. In contrast, TBT elevated the expressions of genes involved in meiotic entry and maintenance (aldhla2, sycp3 and dmc1) while suppressed the mRNA level of gene responsible for terminus of meiotic entry (cyp26a1), in agreement with arrested meiosis and reduced sperm count. Furthermore, TBT significantly elevated the ratios of bax/bcl-2 and tnfrsf1a/tnfrsf1b in testis, which are markers for intrinsic- and extrinsic-apoptotic pathways, consistent with the enhanced TUNEL positive signals in spermatocytes. Moreover, TBT also significantly affected the parameter of reproductive behaviors in treated fish (reflected by decreased frequency of meeting, visits and time spent in spawning area). Consistently, the expressions of genes responsible for the modulation of reproductive behaviors in brain (such as cyp19a1b, kiss2, gnrh3 and ompb) were significantly down-regulated in treated-fish. Interestingly, disrupted reproductive behaviors of untreated female fish were also observed in the present study. The present study indicated that TBT might affect the reproduction of zebrafish male by disrupting the spermatogenesis and reproductive behavior of the fish.


Assuntos
Comportamento Sexual Animal/efeitos dos fármacos , Espermatogênese/efeitos dos fármacos , Compostos de Trialquitina/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/fisiologia , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Feminino , Expressão Gênica/efeitos dos fármacos , Masculino , Meiose/efeitos dos fármacos , Meiose/genética , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Reprodução/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo , Testículo/efeitos dos fármacos , Testículo/metabolismo
5.
Environ Pollut ; 244: 486-494, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30366296

RESUMO

Environmental estrogens are capable of interfering with the spermatogenesis and fertility of fish. However in natural waters, these chemicals are more likely to occur as a combination rather than a single stressor. Whether and how the mixture of xenoestrogens with environmental relevant concentrations may affect fish spermatogenesis remains largely unknown. In this study, male zebrafish adults were administered to 17alpha-ethinylestradiol (EE2) and a mixture of xenoestrogens (Mix (E2, EE2, DES, 4-t-OP, 4-NP and BPA)), with the estrogenic potency equivalent to EE2. After a 60-day exposures, elevated mRNA levels of vitellogenin 1 (vtg1) and estrogen receptor 1 (esr1) in the liver of fish in both treated groups were observed. Moreover, the plasma level of E2 declined significantly in the Mix group and the ratio of 11-KT/E2 was significantly elevated in both treated groups. Consistently, the mRNA level of P450 side-chain cleavage (scc) in the EE2 group and ovarian type aromatase (cyp19a1a) in the Mix group was significantly suppressed. In addition, decreased gonadosomatic index and sperm count in the fish of Mix group were present. Furthermore, increased number of the proliferating germ cells (such as spermatogonia and spermatocytes) was observed in the fish of both groups, suggesting a stimulated germ cell proliferation and meiosis. Accordingly, both exposures significantly up-regulated the mRNA levels of genes in mitosis (cyclinb1) and meiosis (cyp26a1 in EE2 group, aldh1a2, cyp26a1, sycp3 and spo11 in Mix). In addition, decreased number of spermatozoa and increased number of TUNEL-positive signals were present in the testis of fish in the Mix group, indicating an enhanced apoptosis. Further analyses demonstrated the significant elevated expressions of tnfrsf1a and the ratio of tnfrsf1a/tnfrsf1b in the Mix group, suggesting an elevated apoptosis in the testis of fish in the Mix group via extrinsic pathway. The present study greatly extends our understanding of the underlying mechanisms of the reproductive toxicity of xenoestrogens on fish.


Assuntos
Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Estrogênios/sangue , Etinilestradiol/toxicidade , Meiose/efeitos dos fármacos , Espermatogênese/fisiologia , Espermatozoides/citologia , Animais , Exposição Ambiental , Receptor alfa de Estrogênio/metabolismo , Feminino , Hormônios Esteroides Gonadais , Masculino , Receptores Tipo I de Fatores de Necrose Tumoral/biossíntese , Receptores Tipo II do Fator de Necrose Tumoral/biossíntese , Reprodução/fisiologia , Ácido Retinoico 4 Hidroxilase/biossíntese , Contagem de Espermatozoides , Espermatogônias/citologia , Testículo/metabolismo , Vitelogeninas/metabolismo , Peixe-Zebra
6.
Aquat Toxicol ; 200: 206-216, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29775928

RESUMO

Tributyltin (TBT), an organotin acting as aromatase (Cyp19a1) inhibitor, has been found to disrupt gametogenesis and reproductive behaviors in several fish species. However, few studies addressing the mechanisms underlying the impaired gametogenesis and reproduction have been reported. In this study, female adults of zebrafish (Danio rerio) were continuously exposed to two nominal concentrations of TBT (100 and 500 ng/L, actual concentrations: 90.8 ±â€¯1.3 ng/L and 470.3 ±â€¯2.7 ng/L, respectively) for 28 days. After exposures, TBT decreased the total egg number, reduced the hatchability and elevated the mortality of the larvae. Decreased gonadosomatic index (GSI) and altered percentages of follicles in different developmental stages (increased early-stage follicles and reduced mid/late-stage follicles) were also observed in the ovary of TBT-treated fish. TBT also lowered the plasma level of 17ß-estradiol and suppressed the expressions of cyp19a1a in the ovary. In treated fish, up-regulated expressions of aldhla2, sycp3 and dmc1 were present in the ovary, indicating an enhanced level of meiosis. The mRNA level of vtg1 was dramatically suppressed in the liver of TBT-treated fish, suggesting an insufficient synthesis of Vtg protein, consistent with the decreased percentage of mid/late-stage follicles in the ovaries. Moreover, TBT significantly suppressed the reproductive behaviors of the female fish (duration of both sexes simultaneously in spawning area, the frequency of meeting and the visit in spawning area) and down-regulated the mRNA levels of genes involved in the regulation of reproductive behaviors (cyp19a1b, gnrh-3 and kiss 2) in the brain. In addition, TBT significantly suppressed the expressions of serotonin-related genes, such as tph2 (encoding serotonin synthase), pet1 (marker of serotonin neuron) and kiss 1 (the modulator of serotonin synthesis), suggesting that TBT might disrupt the non-reproductive behaviors of zebrafish. The present study demonstrated that TBT may impair the reproductive success of zebrafish females probably through disrupting oogenesis, disturbing reproductive behaviors and altering serotonin synthesis. The present study greatly extends our understanding on the reproductive toxicity of TBT on fish.


Assuntos
Oogênese/efeitos dos fármacos , Reprodução/efeitos dos fármacos , Serotonina/biossíntese , Compostos de Trialquitina/toxicidade , Peixe-Zebra/fisiologia , Animais , Comportamento Animal/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Estradiol/sangue , Feminino , Larva/efeitos dos fármacos , Larva/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Meiose/efeitos dos fármacos , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Serotonina/metabolismo , Vitelogeninas/genética , Vitelogeninas/metabolismo , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/sangue
7.
Fish Physiol Biochem ; 44(3): 789-803, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29340879

RESUMO

In fish, spermatogenesis and somatic growth are mainly regulated by hypothalamic-pituitary-gonadal (HPG) and hypothalamic-pituitary-somatic (HPS) axes, respectively. Xenoestrogens have been reported to impair spermatogenesis in some fishes, and arrest somatic growth in some others, whereas, whether xenoestrogens are capable of disrupting spermatogenesis and somatic growth simultaneously in fish that exhibits sexual dimorphic growth is little known, and the underlying mechanisms remain poorly understood. In this study, male juveniles of yellow catfish (Pelteobagrus fulvidraco), which exhibits a sexual dimorphic growth that favors males, were exposed to diethylstilbestrol (DES) for 28 days. After exposure, DES significantly disrupted the spermatogenesis (decreased gonadal-somatic index (GSI) and germ cell number) and arrested the somatic growth (declined body weight) of the catfish juveniles. Gene expression and plasma steroid analyses demonstrated the suppressed mRNA levels of genes in HPG axis (gnrh-II, fshß, and lhß in the brain and dmrt1, sf1, fshr, cyp17a1, cyp19a1a, and cyp11b2 in the testis) and decreased 17ß-estrodial (E2) and 11-ketotestosterone (11-KT) levels in plasma. Further analysis revealed the arrested germ cell proliferation (cyclin d1), meiosis (dmc1, sycp3), and enhanced apoptosis (decreased bcl-2 and elevated bax/bcl-2 ratio) in the testis. Besides, DES also suppressed the mRNA levels of genes in HPS axis (ghrh, gh, and prl in the brain and ghr, igf1, igf2a, and igf2b in the liver). The suppressed HPG and HPS axes were thus supposed to disturb spermatogenesis and arrest somatic growth in yellow catfish. The present study greatly extended our understanding on the mechanisms underlying the toxicity of DES on spermatogenesis and somatic growth of fish.


Assuntos
Dietilestilbestrol/toxicidade , Estrogênios não Esteroides/toxicidade , Espermatogênese/efeitos dos fármacos , Animais , Peixes-Gato , Estradiol/sangue , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , RNA Mensageiro/metabolismo , Caracteres Sexuais , Testosterona/análogos & derivados , Testosterona/sangue , Vitelogeninas/genética
8.
Aquat Toxicol ; 181: 76-85, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27821350

RESUMO

Mercury (Hg) is a widespread environmental pollutant that can produce severe negative effects on fish even at very low concentrations. However, the mechanisms underlying inorganic Hg-induced oxidative stress and immunotoxicity in the early development stage of fish still need to be clarified. In the present study, zebrafish (Danio rerio) embryos were exposed to different concentrations of Hg2+ (0, 1, 4 and 16µg/L; added as mercuric chloride, HgCl2) from 2h post-fertilization (hpf) to 168hpf. Developmental parameters and total Hg accumulation were monitored during the exposure period, and antioxidant status and the mRNA expression of genes related to the innate immune system were examined at 168hpf. The results showed that increasing Hg2+ concentration and time significantly increased total Hg accumulation in zebrafish embryos-larvae. Exposure to 16µg/L Hg2+ caused developmental damage, including increased mortality and malformation, decreased body length, and delayed hatching period. Meanwhile, HgCl2 exposure (especially in the 16µg/L Hg2+ group) induced oxidative stress affecting antioxidant enzyme (CAT, GST and GPX) activities, endogenous GSH and MDA contents, as well as the mRNA levels of genes (cat1, sod1, gstr, gpx1a, nrf2, keap1, hsp70 and mt) encoding antioxidant proteins. Moreover, the transcription levels of several representative genes (il-1ß, il-8, il-10, tnfα2, lyz and c3) involved in innate immunity were up-regulated by HgCl2 exposure, suggesting that inorganic Hg had the potential to induce immunotoxicity. Taken together, the present study provides evidence that waterborne HgCl2 exposure can induce developmental impairment, oxidative stress and immunotoxicity in the early development stage of fish, which brings insights into the toxicity mechanisms of inorganic Hg in fish.


Assuntos
Cloreto de Mercúrio/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/crescimento & desenvolvimento , Animais , Antioxidantes/metabolismo , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/metabolismo , Desenvolvimento Embrionário/efeitos dos fármacos , Glutationa/metabolismo , Imunidade Inata/efeitos dos fármacos , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Larva/metabolismo , Malondialdeído/metabolismo , Oxirredutases/genética , Oxirredutases/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Poluentes Químicos da Água/química , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
9.
Aquat Toxicol ; 177: 417-24, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27391360

RESUMO

Mercury (Hg) is a prominent environmental contaminant that causes a variety of adverse effects on aquatic organisms. However, the mechanisms underlying inorganic Hg-induced reproductive impairment in fish remains largely unknown. In this study, adult zebrafish were exposed to 0 (control), 15 and 30µg Hg/l (added as mercuric chloride, HgCl2) for 30days, and the effects on histological structure, antioxidant status and sex hormone levels in the ovary and testis, as well as the mRNA expression of genes involved in the hypothalamic-pituitary-gonadal (HPG) axis were analyzed. Exposure to Hg caused pathological lesions in zebrafish gonads, and changed the activities and mRNA levels of antioxidant enzymes (catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx)) as well as the content of glutathione (GSH) and malondialdehyde (MDA). In females, although ovarian 17ß-estradiol (E2) content remained relatively stable, significant down-regulation of lhß, gnrh2, gnrh3, lhr and erα were observed. In males, testosterone (T) levels in the testis significantly decreased after Hg exposure, accompanied by down-regulated expression of gnrh2, gnrh3, fshß and lhß in the brain as well as fshr, lhr, ar, cyp17 and cyp11b in the testis. Thus, our study indicated that waterborne inorganic Hg exposure caused histological damage and oxidative stress in the gonads of zebrafish, and altered sex hormone levels by disrupting the transcription of related HPG-axis genes, which could subsequently impair the reproduction of fish. Different response of the antioxidant defense system, sex hormone and HPG-axis genes between females and males exposed to inorganic Hg indicated the gender-specific regulatory effect by Hg. To our knowledge, this is the first time to explore the effects and mechanisms of inorganic Hg exposure on reproduction at the histological, enzymatic and molecular levels, which will greatly extend our understanding on the mechanisms underlying of reproductive toxicity of inorganic Hg in fish.


Assuntos
Expressão Gênica/efeitos dos fármacos , Mercúrio/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Antioxidantes/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Estradiol/metabolismo , Feminino , Hormônios Esteroides Gonadais/genética , Hormônios Esteroides Gonadais/metabolismo , Gônadas/efeitos dos fármacos , Gônadas/metabolismo , Hormônios Hipotalâmicos/genética , Hormônios Hipotalâmicos/metabolismo , Masculino , Ovário/efeitos dos fármacos , Ovário/metabolismo , Ovário/patologia , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Testículo/efeitos dos fármacos , Testículo/metabolismo , Testículo/patologia , Testosterona/metabolismo , Peixe-Zebra/fisiologia
10.
Environ Sci Pollut Res Int ; 21(16): 9921-30, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24801288

RESUMO

The effects of several silicates (talcum powder (TP), calcium silicate (CS), sodium silicate (SS), and potassium silicate (PS)), in comparison with other amendments (quicklime (QL) and potassium dihydrogen phosphate (PDP)) on cadmium (Cd) uptake by three dicotyledonous crops (Amaranthus hypochondriacus L. Cv. 'K112', Amaranthus tricolor L., and Brassica oleracea var. albiflora Kuntze) were investigated in Cd-contaminated soil. The effects of both application methods of amendments (singly and combined) and timing of application were also evaluated. Sodium silicate was the most effective in reducing crop Cd uptake and translocation, which was diminished by 51% in roots, 53% in stems, and 72% in leaves on average. Application of CS amendment showed greater efficiency than PDP amendment in decreasing Cd uptake by crops and resulted in increased biomass. Potassium silicate only slightly decreased shoot Cd concentration. Combination of PDP and SS was able to overcome the inhibitory effect of SS on crop yield while decreasing Cd concentrations in roots, stems and leaves of the tested crops by average rates of 52, 65, and 68% respectively. Applications of SS and PS significantly reduced the root-to-shoot Cd transfer factor. We found that Si accumulation in crops was not associated with lower Cd concentration, indicating that Si in crops may play a major role in alleviating metal stress rather than inhibiting crop Cd accumulation. We suggested that the inhibitive effect of silicates on crops Cd uptake was majorly attributed to the properties of the silicates, those were their specific effects on soil pH and cations, which increased Cd adsorption by soil and suppressed Cd uptake from soil solution by increasing the relative dissolved concentrations of competing cations.


Assuntos
Agricultura/métodos , Amaranthus/metabolismo , Brassica/metabolismo , Cádmio/metabolismo , Produtos Agrícolas/metabolismo , Silicatos/farmacologia , Poluentes do Solo/metabolismo , Adsorção , Amaranthus/efeitos dos fármacos , Amaranthus/crescimento & desenvolvimento , Transporte Biológico/efeitos dos fármacos , Biomassa , Brassica/efeitos dos fármacos , Brassica/crescimento & desenvolvimento , Cádmio/análise , Produtos Agrícolas/efeitos dos fármacos , Produtos Agrícolas/crescimento & desenvolvimento , Raízes de Plantas/efeitos dos fármacos , Poluentes do Solo/análise
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