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1.
Dermatology ; 240(3): 487-493, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38228098

RESUMO

INTRODUCTION: Dermatofibrosarcoma protuberans (DFSP) is the most common sarcoma of the skin. Although distant metastases are infrequent, DFSP is highly aggressive locally with frequent local recurrences. It has been reported that the presence within the tumour of areas histopathologically mimicking fibrosarcoma may increase the risk of recurrence. OBJECTIVE: The objective of this study was to review the clinical features of our patients with DFSP and the factors associated with recurrence of the tumour, focussing on the presence of fibrosarcomatous areas. METHODS: Retrospective study of patients with DFSP diagnosed in 1990-2021 in a tertiary university hospital. The medical records were reviewed to obtain the following data: age, sex, tumour location, diameter, evolution time, presence of fibrosarcomatous areas, development of recurrence, and follow-up. Factors possibly associated with disease-free survival were analysed with Kaplan-Meier method and multivariate Cox regression. RESULTS: 148 patients (74 women/74 men, mean age 46.28 years, SD 14.431) were included in the study. Tumours involved the head and neck in 15 cases, thorax in 31, abdomen in 16, upper back in 43, lower back in 10, upper extremities in 10, and lower extremities in 23. Fibrosarcoma-like areas were observed in 16 tumours (10.81%). In 17 patients (11.49%), recurrences were observed (13 local recurrences, 3 lung metastasis, and 1 local recurrence with lung metastasis). Fibrosarcomatous DFSP recurred more frequently than classic DFSP (50% vs. 6.82%, respectively), and its disease-free survival was significantly lower (p < 0.001). In multivariate Cox regression, the presence of fibrosarcomatous areas was the only factor influencing disease-free survival. CONCLUSIONS: It is important to identify the fibrosarcomatous variant since it recurs more frequently and has lower recurrence-free survival. Distant metastases, mainly in the lung, are also more frequent in fibrosarcomatous DFSP.


Assuntos
Dermatofibrossarcoma , Recidiva Local de Neoplasia , Neoplasias Cutâneas , Humanos , Dermatofibrossarcoma/patologia , Dermatofibrossarcoma/mortalidade , Feminino , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/mortalidade , Neoplasias Cutâneas/terapia , Recidiva Local de Neoplasia/patologia , Idoso , Intervalo Livre de Doença , Adulto Jovem , Fibrossarcoma/patologia , Fibrossarcoma/mortalidade , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/mortalidade , Adolescente
2.
Mar Drugs ; 21(9)2023 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-37755084

RESUMO

In the present study, the recovery of valuable molecules of proven anti-inflammatory and antimicrobial activity of the acidophilic microalga Coccomyxa onubensis (C. onubensis) were evaluated using green technologies based on ultrasound-assisted extraction (UAE). Using a factorial design (3 × 2) based on response surface methodology and Pareto charts, two types of ultrasonic equipment (bath and probe) were evaluated to recover valuable compounds, including the major terpenoid of C. onubensis, lutein, and the antimicrobial activity of the microalgal extracts obtained under optimal ultrasound conditions (desirability function) was evaluated versus conventional extraction. Significant differences in lutein recovery were observed between ultrasonic bath and ultrasonic probe and conventional extraction. Furthermore, the antimicrobial activity displayed by C. onubensis UAE-based extracts was greater than that obtained in solvent-based extracts, highlighting the effects of the extracts against pathogens such as Enterococcus hirae and Bacillus subtilis, followed by Staphylococcus aureus and Escherichia coli. In addition, gas chromatography-mass spectrometry was performed to detect valuable anti-inflammatory and antimicrobial biomolecules present in the optimal C. onubensis extracts, which revealed that phytol, sterol-like, terpenoid, and even fatty acid structures could also be responsible for the antibacterial activities of the extracts. Moreover, UAE displayed a positive effect on the recovery of valuable molecules, improving biocidal effects. Our study results facilitate the use of green technology as a good tool in algal bioprocess engineering, improving energy consumption and minimizing environmental impacts and process costs, as well as provide a valuable product for applications in the field of biotechnology.


Assuntos
Anti-Infecciosos , Clorófitas , Microalgas , Luteína , Anti-Infecciosos/farmacologia , Antibacterianos/farmacologia , Extratos Vegetais/farmacologia
3.
Dermatology ; 238(3): 587-593, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34569484

RESUMO

BACKGROUND: Cutaneous leiomyoma (CL) is a benign smooth muscle tumour included in painful skin tumours. Multiple CLs are cutaneous markers of hereditary leiomyomatosis and renal cell cancer (HLRCC). OBJECTIVES: To retrospectively review our series of patients with CLs to analyse their clinical features and the association with HLRCC. METHODS: Cases coded as CL in the database of the pathology department between 2004 and 2019 were included in the study. Medical records were retrospectively reviewed to obtain the following data: age, sex, location, number of lesions, diameter, evolution time at diagnosis, suspected clinical diagnosis, tenderness, status of resection margins, development of recurrence, follow-up time, and association with HLRCC. RESULTS: 152 patients had CLs, 89 women and 63 men, mean age 56.26, SD 16.030 years. Subtypes were piloleiomyoma in 62 patients, angioleiomyoma in 80, and genital leiomyoma in 10. All of our 11 patients with multiple lesions corresponded to piloleiomyomas, and HLRCC was confirmed in 8 of them (73%). Patients with HLRCC were younger than patients with piloleiomyomas without HLRCC (34.88 vs. 56.17 years, p = 0.009). Vascular and genital leiomyomyomas were solitary and were not associated with HLRCC. CONCLUSION: In patients with multiple piloleiomyomas HLRCC must be ruled out as it is confirmed in a high proportion of cases. The probability of fumarate hydratase mutation is greater in multiple piloleiomyomas involving both the trunk and upper extremities in the same patient.


Assuntos
Neoplasias Renais , Leiomiomatose , Síndromes Neoplásicas Hereditárias , Neoplasias Cutâneas , Feminino , Fumarato Hidratase/genética , Humanos , Neoplasias Renais/genética , Leiomiomatose/diagnóstico , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Neoplasias Cutâneas/patologia , Neoplasias Uterinas
4.
Am J Dermatopathol ; 43(12): 980-983, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34783704

RESUMO

ABSTRACT: Sarcoidosis induced by anti-PD1 or anti-PDL1 agents such as atezolizumab has recently been reported. It has been suggested that the predilection of sarcoidosis to affect scars is due to the presence of antigens or foreign bodies that can serve as a stimulus for granuloma formation. However, to the best of our knowledge, sarcoidosis-specific skin lesions have not to date been reported involving xanthelasma. We report a patient who developed specific lesions of sarcoidosis infiltrating some xanthelasmata 6 months after starting treatment with atezolizumab. A 69-year-old woman was referred to the dermatology department for infiltration of xanthelasmata. The patient was being treated with atezolizumab for metastatic uterine carcinosarcoma. Cutaneous biopsy from an infiltrated xanthelasma and from still yellow, no infiltrated xanthelasma showed differing proportions of foamy histiocytes and sarcoid granulomas. On physical examination, erythemato-marronaceous papules clustered on both knees, and not previously detected by the patient, were observed. The biopsy showed sarcoid dermal granulomas with foreign bodies. A chest computerized tomography scan was consistent with intrathoracic involvement of sarcoidosis. Endobronchial ultrasound-guided transbronchial needle aspiration of a mediastinal lymphadenopathy showed epithelioid cell granulomas. Histopathologically, the foamy histiocytes of xanthelasma seem to be replaced by or evolve to epithelioid cells to form sarcoid granulomas. The possible pathogenic mechanism is discussed. Dermatologists and dermatopathologists should bear in mind that sarcoidosis can present as infiltration of pre-existing xanthelasmata.


Assuntos
Anticorpos Monoclonais Humanizados/efeitos adversos , Antineoplásicos/efeitos adversos , Sarcoidose/induzido quimicamente , Sarcoidose/patologia , Idoso , Carcinossarcoma/tratamento farmacológico , Feminino , Humanos , Neoplasias Uterinas/tratamento farmacológico , Xantomatose/patologia
5.
Adv Exp Med Biol ; 1261: 165-174, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33783738

RESUMO

Haloarchaea are halophilic microorganisms belonging to the Archaea domain that inhabit salty environments (mainly soils and water) all around the world. Most of the genera included in this group are able to produce carotenoids at significant concentrations (even wild-type strains). The major carotenoid produced by the cells is bacterioruberin (and its derivatives), which is only produced by this kind of microbes. Nevertheless, the understanding of carotenoid metabolism in haloarchaea, its regulation, and the roles of carotenoid derivatives in this group of extreme microorganisms remains mostly unrevealed. Besides, potential biotechnological uses of haloarchaeal pigments are poorly explored. This work summarizes what it has been described so far about carotenoid production by haloarchaea, haloarchaeal carotenoid production at large scale, as well as the potential uses of haloarchaeal pigments in biotechnology and biomedicine.


Assuntos
Archaea , Carotenoides , Archaea/genética , Biotecnologia , Pigmentação
6.
Mar Drugs ; 19(2)2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33578828

RESUMO

Haloarchaea produce C50 carotenoids such as bacterioruberin, which are of biotechnological in-terest. This study aimed to analyze the effect of different environmental and nutritional conditions on the cellular growth and dynamics of carotenoids accumulation in Haloferax mediterranei. The maximum production of carotenoids (40 µg·mL-1) was obtained during the stationary phase of growth, probably due to nutrient-limiting conditions (one-step culture). By seven days of culture, 1 mL culture produced 22.4 mg of dry weight biomass containing 0.18 % (w/w) of carotenoids. On the other hand, carbon-deficient cultures (low C/N ratio) were observed to be optimum for C50 bacterioruberin production by Hfx. mediterranei, but negatively affected the growth of cells. Thus, a two-steps process was evaluated for optimum carotenoids yield. In the first step, a nutri-ent-repleted culture medium enabled the haloarchaea to produce biomass, while in the second step, the biomass was incubated under osmotic stress and in a carbon-deficient medium. Under the conditions used, the obtained biomass contained 0.27% (w/w) of carotenoids after seven days, which accounts for 58.49 µg·mL-1 of carotenoids for a culture with turbidity 14.0.


Assuntos
Biotecnologia/métodos , Carotenoides/metabolismo , Haloferax mediterranei/metabolismo , Biomassa , Carbono/química , Meios de Cultura , Fatores de Tempo
8.
Mar Drugs ; 17(9)2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31500208

RESUMO

Haloarchaea are halophilic microorganisms belonging to the archaea domain that inhabit salty environments (mainly soils and water) all over the world. Most of the genera included in this group can produce carotenoids at significant concentrations (even wild-type strains). The major carotenoid produced by the cells is bacterioruberin (and its derivatives), which is only produced by this kind of microbes and few bacteria, like Micrococcus roseus. Nevertheless, the understanding of carotenoid metabolism in haloarchaea, its regulation, and the roles of carotenoid derivatives in this group of extreme microorganisms remains mostly unrevealed. Besides, potential biotechnological uses of haloarchaeal pigments are poorly explored. This work summarises what it has been described so far about carotenoids from haloarchaea and their production at mid- and large-scale, paying special attention to the most recent findings on the potential uses of haloarchaeal pigments in biomedicine.


Assuntos
Archaea/metabolismo , Carotenoides/metabolismo , Animais , Bactérias/metabolismo , Biotecnologia/métodos , Ambientes Extremos , Humanos , Pigmentação/fisiologia
9.
Molecules ; 24(22)2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31717936

RESUMO

Haematococcus pluvialis is known to be a natural source of antioxidants for numerous applications. In this study, an oleoresin rich in carotenoids extracted by supercritical CO2 treatment of H. pluvialis was extensively characterized for its antioxidant capacity. Carotenoid content, fatty acid profile, total phenol content, antioxidant capacity, and viscosity of the oleoresin were determined with the aim of ascertaining the potential of the oleoresin in terms of its antioxidant content for food applications. The oleoresin contained 96.22 mg/g of total astaxanthin (which includes free astaxanthin and astaxanthin esters) and mostly included unsaturated fatty acids (~78% of total fatty acids). High total phenol content and ferric reducing antioxidant potential indicated high antioxidant capacity, but oxygen radical absorbance capacity was lower compared to the oleoresin samples obtained from other species. The oleoresin was a non-Newtonian fluid since it had shear-thinning (pseudoplastic) and shear-thickening (dilatant) flow. Therefore, the H. pluvialis oleoresin is a potential alternative in developing functional ingredients for designing healthy food products. To the best of our knowledge, this is the first study that has reported an extensive characterization of the antioxidant properties of a microalgal oleoresin obtained by means of supercritical CO2 fluid extraction.


Assuntos
Antioxidantes/química , Antioxidantes/farmacologia , Clorófitas/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Carotenoides/química , Carotenoides/farmacologia , Fenômenos Químicos , Cromatografia Líquida de Alta Pressão , Ácidos Graxos , Hidrólise , Fenóis/química , Fenóis/farmacologia , Temperamento , Viscosidade
11.
Mar Drugs ; 16(6)2018 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-29890662

RESUMO

Carotenoids are among the most abundant natural pigments available in nature. These pigments have received considerable attention because of their biotechnological applications and, more importantly, due to their potential beneficial uses in human healthcare, food processing, pharmaceuticals and cosmetics. These bioactive compounds are in high demand throughout the world; Europe and the USA are the markets where the demand for carotenoids is the highest. The in vitro synthesis of carotenoids has sustained their large-scale production so far. However, the emerging modern standards for a healthy lifestyle and environment-friendly practices have given rise to a search for natural biocompounds as alternatives to synthetic ones. Therefore, nowadays, biomass (vegetables, fruits, yeast and microorganisms) is being used to obtain naturally-available carotenoids with high antioxidant capacity and strong color, on a large scale. This is an alternative to the in vitro synthesis of carotenoids, which is expensive and generates a large number of residues, and the compounds synthesized are sometimes not active biologically. In this context, marine biomass has recently emerged as a natural source for both common and uncommon valuable carotenoids. Besides, the cultivation of marine microorganisms, as well as the downstream processes, which are used to isolate the carotenoids from these microorganisms, offer several advantages over the other approaches that have been explored previously. This review summarizes the general properties of the most-abundant carotenoids produced by marine microorganisms, focusing on the genuine/rare carotenoids that exhibit interesting features useful for potential applications in biotechnology, pharmaceuticals, cosmetics and medicine.


Assuntos
Organismos Aquáticos/metabolismo , Biotecnologia/métodos , Carotenoides/biossíntese , Microalgas/metabolismo , Biomassa , Carotenoides/isolamento & purificação , Carotenoides/uso terapêutico , Carotenoides/toxicidade , Suplementos Nutricionais , Humanos
12.
Mar Drugs ; 16(12)2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-30513601

RESUMO

Microalgae have been widely recognized as a valuable source of natural, bioactive molecules that can benefit human health. Some molecules of commercial value synthesized by the microalgal metabolism have been proven to display anti-inflammatory activity, including the carotenoids lutein and astaxanthin, the fatty acids EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid), and sulphated polysaccharides. These molecules can accumulate to a certain extent in a diversity of microalgae species. A production process could become commercially feasible if the productivity is high and the overall production process costs are minimized. The productivity of anti-inflammatory molecules depends on each algal species and the cultivation conditions, the latter being mostly related to nutrient starvation and/or extremes of temperature and/or light intensity. Furthermore, novel bioprocess tools have been reported which might improve the biosynthesis yields and productivity of those target molecules and reduce production costs simultaneously. Such novel tools include the use of chemical triggers or enhancers to improve algal growth and/or accumulation of bioactive molecules, the algal growth in foam and the surfactant-mediated extraction of valuable compounds. Taken together, the recent findings suggest that the combined use of novel bioprocess strategies could improve the technical efficiency and commercial feasibility of valuable microalgal bioproducts production, particularly anti-inflammatory compounds, in large scale processes.


Assuntos
Anti-Inflamatórios/metabolismo , Fatores Biológicos/metabolismo , Microalgas/metabolismo , Fotobiorreatores , Tensoativos/farmacologia , Anti-Inflamatórios/isolamento & purificação , Fatores Biológicos/isolamento & purificação , Humanos , Luz , Microalgas/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Temperatura
13.
Mar Drugs ; 16(10)2018 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-30304770

RESUMO

Haloferax mediterranei produces C50 carotenoids that have strong antioxidant properties. The response surface methodology (RSM) tool helps to accurately analyze the most suitable conditions to maximize C50 carotenoids production by haloarchaea. The effects of temperature (15⁻50 °C), pH (4-10), and salinity (5⁻28% NaCl (w/v)) on the growth and carotenoid content of H. mediterranei were analyzed using the RSM approach. Growth was determined by measuring the turbidity at 600 nm. To determine the carotenoid content, harvested cells were lysed by freeze/thawing, then re-suspended in acetone and the total carotenoid content determined by measuring the absorbance at 494 nm. The analysis of carotenoids was performed by an HPLC system coupled with mass spectrometry. The results indicated the theoretical optimal conditions of 36.51 or 36.81 °C, pH of 8.20 or 8.96, and 15.01% or 12.03% (w/v) salinity for the growth of haloarchaea (OD600 = 12.5 ± 0.64) and production of total carotenoids (3.34 ± 0.29 mg/L), respectively. These conditions were validated experimentally for growth (OD600 = 13.72 ± 0.98) and carotenoid production (3.74 ± 0.20 mg/L). The carotenoid profile showed four isomers of bacterioruberin (89.13%). Our findings suggest that the RSM approach is highly useful for determining optimal conditions for large-scale production of bacterioruberin by haloarchaea.


Assuntos
Carotenoides/química , Haloferax mediterranei/química , Cromatografia Líquida de Alta Pressão/métodos , Concentração de Íons de Hidrogênio , Espectrometria de Massas/métodos , Cloreto de Sódio/química
14.
Mar Drugs ; 14(5)2016 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-27213407

RESUMO

A greater insight on the control of the interactions between microalgae and other microorganisms, particularly bacteria, should be useful for enhancing the efficiency of microalgal biomass production and associated valuable compounds. Little attention has been paid to the controlled utilization of microalgae-bacteria consortia. However, the studies of microalgal-bacterial interactions have revealed a significant impact of the mutualistic or parasitic relationships on algal growth. The algal growth, for instance, has been shown to be enhanced by growth promoting factors produced by bacteria, such as indole-3-acetic acid. Vitamin B12 produced by bacteria in algal cultures and bacterial siderophores are also known to be involved in promoting faster microalgal growth. More interestingly, enhancement in the intracellular levels of carbohydrates, lipids and pigments of microalgae coupled with algal growth stimulation has also been reported. In this sense, massive algal production might occur in the presence of bacteria, and microalgae-bacteria interactions can be beneficial to the massive production of microalgae and algal products. This manuscript reviews the recent knowledge on the impact of the microalgae-bacteria interactions on the production of microalgae and accumulation of valuable compounds, with an emphasis on algal species having application in aquaculture.


Assuntos
Bactérias , Biomassa , Microalgas/fisiologia , Biodegradação Ambiental , Humanos
15.
Mar Drugs ; 13(9): 5508-32, 2015 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-26308012

RESUMO

The production of pigments by halophilic archaea has been analysed during the last half a century. The main reasons that sustains this research are: (i) many haloarchaeal species possess high carotenoids production availability; (ii) downstream processes related to carotenoid isolation from haloarchaea is relatively quick, easy and cheap; (iii) carotenoids production by haloarchaea can be improved by genetic modification or even by modifying several cultivation aspects such as nutrition, growth pH, temperature, etc.; (iv) carotenoids are needed to support plant and animal life and human well-being; and (v) carotenoids are compounds highly demanded by pharmaceutical, cosmetic and food markets. Several studies about carotenoid production by haloarchaea have been reported so far, most of them focused on pigments isolation or carotenoids production under different culture conditions. However, the understanding of carotenoid metabolism, regulation, and roles of carotenoid derivatives in this group of extreme microorganisms remains mostly unrevealed. The uses of those haloarchaeal pigments have also been poorly explored. This work summarises what has been described so far about carotenoids production by haloarchaea and their potential uses in biotechnology and biomedicine. In particular, new scientific evidence of improved carotenoid production by one of the better known haloarchaeon (Haloferax mediterranei) is also discussed.


Assuntos
Carotenoides/metabolismo , Haloferax/metabolismo , Animais , Biotecnologia/economia , Biotecnologia/métodos , Humanos
16.
J Neurovirol ; 20(6): 583-90, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25227931

RESUMO

In tropical spastic paraparesis, spinal cord atrophy is a well-known finding in magnetic resonance imaging. But in contrast to histological reports, focal lesions of the spinal cord have only been described in imaging reports in exceptional acute cases. Here, we looked for such focal lesions and for alterations of diffusion tensor imaging parameters of the long fibre tracts in the usual case of a long-standing and slowly progressive disease. We examined 10 symptomatic patients, 11 seropositive, but asymptomatic human T-lymphotrophic virus type 1 carriers and 18 seronegative volunteers as controls. Sagittal and transversal T2-weighted images were visually assessed for atrophy and focal cord lesions. The spinal cord cross-sectional areas and the segmental cord volumes were measured at all levels. High-resolution diffusion tensor imaging was performed in sagittal planes from the bregma down to the cervical spine. For tractography and calculation of fractional anisotropy and mean diffusivity, we used manufacturer-provided software. Two-thirds of patients showed focal lesions affecting the antero-lateral columns and in two cases also the dorsal columns. Compared to carriers and volunteers, patients presented a significant spinal cord atrophy and a reduction of fractional anisotropy (p < 0.05), correlating more to duration of symptoms than to clinical impairment. Because our carriers did not show a significant atrophy, focal lesions or a change of diffusion tensor imaging parameters, we need further long-term studies to see if these parameters at some stage may be used as early indicators of spinal cord affection in virus carriers.


Assuntos
Doenças Assintomáticas , Atrofia/patologia , Paraparesia Espástica Tropical/patologia , Medula Espinal/patologia , Adulto , Atrofia/diagnóstico , Portador Sadio , Estudos de Casos e Controles , Imagem de Tensor de Difusão , Feminino , Vírus Linfotrópico T Tipo 1 Humano/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Paraparesia Espástica Tropical/diagnóstico , Índice de Gravidade de Doença
17.
ScientificWorldJournal ; 2014: 401265, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24688385

RESUMO

The aim of this work was to study the effect of Se(+VI) on viability, cell morphology, and selenomethionine accumulation of the green alga Chlorella sorokiniana grown in batch cultures. Culture exposed to sublethal Se concentrations of 40 mg · L(-1) (212 µM) decreased growth rates for about 25% compared to control. A selenate EC50 value of 45 mg · L(-1) (238.2 µM) was determined. Results showed that chlorophyll and carotenoids contents were not affected by Se exposure, while oxygen evolution decreased by half. Ultrastructural studies revealed granular stroma, fingerprint-like appearance of thylakoids which did not compromise cell activity. Unlike control cultures, SDS PAGE electrophoresis of crude extracts from selenate-exposed cell cultures revealed appearance of a protein band identified as 53 kDa Rubisco large subunit of Chlorella sorokiniana, suggesting that selenate affects expression of the corresponding chloroplast gene as this subunit is encoded in the chloroplast DNA. Results revealed that the microalga was able to accumulate up to 140 mg · kg(-1) of SeMet in 120 h of cultivation. This paper shows that Chlorella sorokiniana biomass can be enriched in the high value aminoacid SeMet in batch cultures, while keeping photochemical viability and carbon dioxide fixation activity intact, if exposed to suitable sublethal concentrations of Se.


Assuntos
Técnicas de Cultura Celular por Lotes/métodos , Reatores Biológicos/microbiologia , Chlorella/citologia , Chlorella/fisiologia , Ácido Selênico/administração & dosagem , Selenometionina/isolamento & purificação , Selenometionina/metabolismo , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/fisiologia , Tamanho Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Chlorella/efeitos dos fármacos , Relação Dose-Resposta a Droga
18.
Microorganisms ; 12(3)2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38543485

RESUMO

The main entrance point of highly toxic organic Hg forms, including methylmercury (MeHg), into the aquatic food web is phytoplankton, which is greatly represented by various natural microalgal species. Processes associated with MeHg fate in microalgae cells such as uptake, effects on cells and toxicity, Hg biotransformation, and intracellular stability are detrimental to the process of further biomagnification and, as a consequence, have great importance for human health. The study of MeHg uptake and distribution in cultures of marine halophile Dunaliella salina and freshwater acidophilic alga Coccomyxa onubensis demonstrated that most of the MeHg is imported inside the cell, while cell surface adhesion is insignificant. Almost all MeHg is removed from the culture medium after 72 h. Significant processes in rapid MeHg removal from liquid medium are its abiotic photodegradation and volatilization associated with algal enzymatic activity. The maximum intracellular accumulation for both species was in 80 nM MeHg-exposed cultures after 24 h of exposure for D. salina (from 27 to 34 µg/gDW) and at 48 h for C. onubensis (up to 138 µg/gDW). The different Hg intakes in these two strains could be explained by the lack of a rigid cell wall in D. salina and the higher chemical ability of MeHg to pass through complex cell wall structures in C. onubensis. Electron microscopy studies on the ultrastructure of both strains demonstrated obvious microvacuolization in the form of many very small vacuoles and partial cell membrane disruption in 80 nM MeHg-exposed cultures. Results further showed that Coccomyxa onubensis is a good candidate for MeHg-contaminated water reclamation due to its great robustness at nanomolar concentrations of MeHg coupled with its very high intake and almost complete Hg removal from liquid medium at the MeHg levels tested.

19.
Int J Rheum Dis ; 27(1): e14806, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37358296

RESUMO

We present the case of a 63-year-old woman who developed dermatomyositis after hematopoietic stem cell transplantation. Anti-melanoma differentiation-associated gene 5 (anti-MDA5) antibodies were positive and pulmonary involvement was severe and progressive. In addition, we also report that the patient's sister and donor also developed dermatomyositis. She had positive anti-PL7 antibodies and negative anti-MDA5 antibodies. The occurrence of autoimmune diseases after allogeneic hematopoietic stem cell transplantation is infrequent and difficult to interpret due to the reconstitution of the immune system and the multifactorial origin of most of these diseases. To our knowledge, this is the first described case of a hematopoietic progenitor transplant donor and recipient developing dermatomyositis. These findings make us wonder whether the dermatomyositis in this case is due to a shared genetic predisposition or to the donor's disease developing in the recipient.


Assuntos
Dermatomiosite , Transplante de Células-Tronco Hematopoéticas , Feminino , Humanos , Pessoa de Meia-Idade , Dermatomiosite/diagnóstico , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Doadores de Tecidos , Autoanticorpos
20.
Microorganisms ; 11(8)2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37630594

RESUMO

The biogeochemical cycling of mercury in aquatic environments is a complex process driven by various factors, such as ambient temperature, seasonal variations, methylating bacteria activity, dissolved oxygen levels, and Hg interaction with dissolved organic matter (DOM). As a consequence, part of the Hg contamination from anthropogenic activity that was buried in sediments is reinserted into water columns mainly in highly toxic organic Hg forms (methylmercury, dimethylmercury, etc.). This is especially prominent in the coastal shallow waters of industrial regions worldwide. The main entrance point of these highly toxic Hg forms in the aquatic food web is the naturally occurring phytoplankton. Hg availability, intake, effect on population size, cell toxicity, eventual biotransformation, and intracellular stability in phytoplankton are of the greatest importance for human health, having in mind that such Hg incorporated inside the phytoplankton cells due to biomagnification effects eventually ends up in aquatic wildlife, fish, seafood, and in the human diet. This review summarizes recent findings on the topic of organic Hg form interaction with natural phytoplankton and offers new insight into the matter with possible directions of future research for the prevention of Hg biomagnification in the scope of climate change and global pollution increase scenarios.

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