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1.
Nature ; 585(7824): 234-238, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32908266

RESUMO

The transport of carbon into Earth's mantle is a critical pathway in Earth's carbon cycle, affecting both the climate and the redox conditions of the surface and mantle. The largest unconstrained variables in this cycle are the depths to which carbon in sediments and altered oceanic crust can be subducted and the relative contributions of these reservoirs to the sequestration of carbon in the deep mantle1. Mineral inclusions in sublithospheric, or 'superdeep', diamonds (derived from depths greater than 250 kilometres) can be used to constrain these variables. Here we present oxygen isotope measurements of mineral inclusions within diamonds from Kankan, Guinea that are derived from depths extending from the lithosphere to the lower mantle (greater than 660 kilometres). These data, combined with the carbon and nitrogen isotope contents of the diamonds, indicate that carbonated igneous oceanic crust, not sediment, is the primary carbon-bearing reservoir in slabs subducted to deep-lithospheric and transition-zone depths (less than 660 kilometres). Within this depth regime, sublithospheric inclusions are distinctly enriched in 18O relative to eclogitic lithospheric inclusions derived from crustal protoliths. The increased 18O content of these sublithospheric inclusions results from their crystallization from melts of carbonate-rich subducted oceanic crust. In contrast, lower-mantle mineral inclusions and their host diamonds (deeper than 660 kilometres) have a narrow range of isotopic values that are typical of mantle that has experienced little or no crustal interaction. Because carbon is hosted in metals, rather than in diamond, in the reduced, volatile-poor lower mantle2, carbon must be mobilized and concentrated to form lower-mantle diamonds. Our data support a model in which the hydration of the uppermost lower mantle by subducted oceanic lithosphere destabilizes carbon-bearing metals to form diamond, without disturbing the ambient-mantle stable-isotope signatures. This transition from carbonate slab melting in the transition zone to slab dehydration in the lower mantle supports a lower-mantle barrier for carbon subduction.

2.
Int J Toxicol ; 42(1): 19-36, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36523256

RESUMO

Liver responses are the most common endpoints used as the basis for setting exposure standards. Liver hepatocytes play a vital role in biotransformation of xenobiotics, but non-parenchymal cells (NPCs) in the liver are also involved in certain liver responses. Development of in vitro systems that more faithfully capture liver responses to reduce reliance on animals is a major focus of New Approach Methodology (NAMs). Since rodent regulatory studies are frequently the sole source safety assessment data, mode-of-action data, and used for risk assessments, in vitro rodent models that reflect in vivo responses need to be developed to reduce reliance on animal models. In the work presented in this paper, we developed a 2-D hepatocyte monoculture and 2-D liver cell co-culture system using rat liver cells. These models were assessed for conditions for short-term stability of the cultures and phenotypic and transcriptomic responses of 2 prototypic hepatotoxicants compounds - acetaminophen and phenobarbital. The optimized multi-cellular 2-D culture required use of freshly prepared hepatocytes and NPCs from a single rat, a 3:1 ratio of hepatocytes to NPCs and growth medium using 50% Complete Williams E medium (WEM) and 50% Endothelial Cell Medium (ECM). The transcriptomic responses of the 2 model systems to PB were compared to previous studies from TG-Gates on the gene expression changes in intact rats and the co-culture model responses were more representative of the in vivo responses. Transcriptomic read-outs promise to move beyond conventional phenotypic evaluations with these in vitro NAMs and provide insights about modes of action.


Assuntos
Hepatócitos , Fígado , Ratos , Animais , Técnicas de Cocultura , Hepatócitos/metabolismo , Fígado/metabolismo , Acetaminofen/toxicidade , Modelos Biológicos , Células Cultivadas
3.
Br J Dermatol ; 185(3): 616-626, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33657677

RESUMO

BACKGROUND: Supportive care is the cornerstone of management of adult and paediatric Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN). However, consensus on the modalities of supportive care is lacking. OBJECTIVES: Our aim in this international multicentric Delphi exercise was to establish a multidisciplinary expert consensus to standardize recommendations regarding supportive care in the acute phase of SJS/TEN. METHODS: Participants were sent a survey via the online tool SurveyMonkey, consisting of 103 statements organized into 11 topics: multidisciplinary team composition, suspect drug management, infection prevention, fluid resuscitation and prevention of hypothermia, nutritional support, pain and psychological distress management, management of acute respiratory failure, local skincare, ophthalmological management, management of other mucosa, and additional measures. Participants evaluated the level of appropriateness of each statement on a scale of 1 (extremely inappropriate) to 9 (extremely appropriate). The results were analysed according to the RAND/UCLA Appropriateness Method. RESULTS: Forty-five participants from 13 countries (on three continents) participated. After the first round, a consensus was obtained for 82.5% of the 103 initially proposed statements. After the second round, a final consensus was obtained for 102 statements. CONCLUSIONS: We have reached an international Delphi-based consensus on best supportive care practice for SJS/TEN. Our expert consensus should help guide physicians in treating patients with SJS/TEN and thereby improve short-term prognosis and the risk of sequelae.


Assuntos
Síndrome de Stevens-Johnson , Adulto , Criança , Consenso , Humanos , Pesquisa , Estudos Retrospectivos , Síndrome de Stevens-Johnson/diagnóstico , Síndrome de Stevens-Johnson/terapia
4.
Nature ; 527(7577): 221-5, 2015 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-26560300

RESUMO

Scientific theories of how subduction and plate tectonics began on Earth--and what the tectonic structure of Earth was before this--remain enigmatic and contentious. Understanding viable scenarios for the onset of subduction and plate tectonics is hampered by the fact that subduction initiation processes must have been markedly different before the onset of global plate tectonics because most present-day subduction initiation mechanisms require acting plate forces and existing zones of lithospheric weakness, which are both consequences of plate tectonics. However, plume-induced subduction initiation could have started the first subduction zone without the help of plate tectonics. Here, we test this mechanism using high-resolution three-dimensional numerical thermomechanical modelling. We demonstrate that three key physical factors combine to trigger self-sustained subduction: (1) a strong, negatively buoyant oceanic lithosphere; (2) focused magmatic weakening and thinning of lithosphere above the plume; and (3) lubrication of the slab interface by hydrated crust. We also show that plume-induced subduction could only have been feasible in the hotter early Earth for old oceanic plates. In contrast, younger plates favoured episodic lithospheric drips rather than self-sustained subduction and global plate tectonics.

5.
Br J Dermatol ; 181(3): 544-553, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30636037

RESUMO

BACKGROUND: The high prevalence of actinic keratosis (AK) requires the optimal use of healthcare resources. OBJECTIVES: To gain insight in to the healthcare utilization of people with AK in a population-based cohort, and the management of AK in a primary and secondary care setting. METHODS: A retrospective cohort study using three complementary data sources was conducted to describe the use of care, diagnosis, treatment and follow-up of patients with AK in the Netherlands. Data sources consisted of a population-based cohort study (Rotterdam Study), routine general practitioner (GP) records (Integrated Primary Care Information) and nationwide claims data (DRG Information System). RESULTS: In the population-based cohort (Rotterdam Study), 69% (918 of 1322) of participants diagnosed with AK during a skin-screening visit had no previous AK-related visit in their GP record. This proportion was 50% for participants with extensive AK (i.e. ≥ 10 AKs; n = 270). Cryotherapy was the most used AK treatment by both GPs (78%) and dermatologists (41-56%). Topical agents were the second most used treatment by dermatologists (13-21%) but were rarely applied in primary care (2%). During the first AK-related GP visit, 31% (171 of 554) were referred to a dermatologist, and the likelihood of being referred was comparable between low- and high-risk patients, which is inconsistent with the Dutch general practitioner guidelines for 'suspicious skin lesions' from 2017. Annually, 40 000 new claims representing 13% of all dermatology claims were labelled as cutaneous premalignancy. Extensive follow-up rates (56%) in secondary care were registered, while only 18% received a claim for a subsequent cutaneous malignancy in 5 years. CONCLUSIONS: AK management seems to diverge from guidelines in both primary and secondary care. Underutilization of field treatments, inappropriate treatments and high referral rates without proper risk stratification in primary care, combined with extensive follow-up in secondary care result in the inefficient use of healthcare resources and overburdening in secondary care. Efforts directed to better risk differentiation and guideline adherence may prove useful in increasing the efficiency in AK management. What's already known about this topic? The prevalence of actinic keratosis (AK) is high and, in particular, multiple AKs are a strong skin cancer predictor. The high prevalence of AK requires optimal use of healthcare resources. Nevertheless, (population based) AK healthcare utilization and management data are very rare. What does this study add? Although AK-related care already consumes substantial resources, about 70% of the AK population has never received care. Primary care AK management demonstrated underutilization of topical therapies and high referral rates without proper risk stratification, while in secondary care the extensive follow-up schedules were applied. This inefficient use of healthcare resources highlights the need for better harmonization and risk stratification to increase the efficiency of AK care.


Assuntos
Ceratose Actínica/terapia , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Padrões de Prática Médica/estatística & dados numéricos , Atenção Primária à Saúde/estatística & dados numéricos , Atenção Secundária à Saúde/estatística & dados numéricos , Demandas Administrativas em Assistência à Saúde/estatística & dados numéricos , Assistência ao Convalescente/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Crioterapia/estatística & dados numéricos , Bases de Dados Factuais/estatística & dados numéricos , Fármacos Dermatológicos/uso terapêutico , Dermatologistas/normas , Dermatologistas/estatística & dados numéricos , Feminino , Clínicos Gerais/normas , Clínicos Gerais/estatística & dados numéricos , Fidelidade a Diretrizes/estatística & dados numéricos , Humanos , Ceratose Actínica/diagnóstico , Masculino , Pessoa de Meia-Idade , Países Baixos , Guias de Prática Clínica como Assunto , Padrões de Prática Médica/normas , Atenção Primária à Saúde/normas , Encaminhamento e Consulta/normas , Encaminhamento e Consulta/estatística & dados numéricos , Estudos Retrospectivos , Medição de Risco/normas , Medição de Risco/estatística & dados numéricos , Atenção Secundária à Saúde/normas
6.
J Anat ; 233(4): 552-556, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30040133

RESUMO

Recently, alterations in fascial gliding-like movement have been invoked as critical in the etiology of myofascial pain. Various methods have been attempted for the relief of this major and debilitating clinical problem. Paramount have been attempts to restore correct gliding between fascial layers and the movement over bone, joint, and muscular structures. One of the key elements that underlies such fascial movement is hyaluronan. However, until now, the precise content of hyaluronan within fasciae has been unknown. This study quantifies for the first time the hyaluronan content of human fascial samples obtained from a variety of anatomic sites. Here, we demonstrate that the average amount varies according to anatomic site, and according to the different kinds of sliding properties of the particular fascia. For example, the fascia lata has 35 µg of hyaluronan per gram of tissue, similar to that of the rectus sheath (29 µg g-1 ). However, the types of fascia adherent to muscle contain far less hyaluronan: 6 µg g-1 in the fascia overlying the trapezius and deltoid muscles. In the fascia that surrounds joints, the hyaluronan increases to 90 µg g-1 , such as in the retinacula of the ankle, where greater degrees of movement occur. Surprisingly, no significant differences were detected at any site as a function of age or sex (P-value > 0.05, t-test) with the sole exception of the plantar fascia. This work can provide a better understanding of the role of hyaluronan in fascia. It will facilitate a better comprehension of the modulation of the hyaluronan-rich layer that occurs in relation to the various conditions that affect fascia, and the diverse factors that underlie the attendant pathologies.


Assuntos
Fáscia/química , Ácido Hialurônico/análise , Humanos
7.
Br J Dermatol ; 179(4): 863-871, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29723914

RESUMO

BACKGROUND: Cancer risk following long-term exposure to systemic immunomodulatory therapies in patients with psoriasis is possible. OBJECTIVES: To assess a dose-response relationship between cumulative length of exposure to biological therapy and risk of cancer. METHODS: Four national studies (a healthcare database from Israel, and prospective cohorts form Italy, Spain and the U.K. and Republic of Ireland) collaborating through Psonet (European Registry of Psoriasis) participated in these nested case-control studies, including nearly 60 000 person-years of observation. 'Cases' were patients who developed an incident cancer. Patients with previous cancers and benign or in situ tumours were excluded. Four cancer-free controls were matched to each case on year of birth, sex, geographic area and registration year. Follow-up for controls was censored at the date of cancer diagnosis for the matched case. Conditional logistic regression was performed by each registry. Results were pooled using random-effects meta-analysis. RESULTS: A total of 728 cases and 2671 controls were identified. After matching, differences between cases and controls were present for the Charlson Comorbidity Index in all three registries, and in the prevalence of previous exposure to psoralen-ultraviolet A and smoking (the British Association of Dermatologists Biologic Interventions Register only). The risk of first cancers was not significantly associated with cumulative exposure to biologics (adjusted odds ratio per year of exposure 1·02, 95% confidence interval 0·92-1·13). Results were similar if squamous and basal cell carcinomas were included in the outcome. CONCLUSIONS: Cumulative length of exposure to biological therapies in patients with psoriasis in real-world clinical practice does not appear to be linked to a higher risk of cancer after several years of use.


Assuntos
Produtos Biológicos/efeitos adversos , Fármacos Dermatológicos/efeitos adversos , Fatores Imunológicos/efeitos adversos , Neoplasias/epidemiologia , Psoríase/tratamento farmacológico , Produtos Biológicos/administração & dosagem , Fármacos Dermatológicos/administração & dosagem , Relação Dose-Resposta a Droga , Europa (Continente)/epidemiologia , Humanos , Fatores Imunológicos/administração & dosagem , Incidência , Israel/epidemiologia , Neoplasias/induzido quimicamente , Neoplasias/imunologia , Psoríase/imunologia , Sistema de Registros/estatística & dados numéricos , Fatores de Tempo
8.
J Eur Acad Dermatol Venereol ; 32(2): 245-253, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28898541

RESUMO

BACKGROUND: Biologics have greatly improved psoriasis management. However, primary and secondary non-response to treatment requires innovative strategies to optimize outcomes. OBJECTIVE: To describe the use of combined treatment of biologics with conventional systemic agents or phototherapy in daily clinical practice. METHODS: We collected data on frequency of use, demographics, treatment characteristics and drug survival of biologics combined with conventional systemic agents or phototherapy in five PSONET registries. RESULTS: Of 9922 biologic treatment cycles, 982 (9.9%) were identified as combination treatment. 72.9% of treatment cycles concerned concomitant use of methotrexate, 25.3% concerned concomitant UVB therapy, acitretin or cyclosporin and 1.8% concerned combined treatment with PUVA, fumaric acids or a second biologic. Substantial variation was detected in type and frequency of combination treatments prescribed across registries. Patients initiated on combined treatment had generally severe disease and were affected with psoriasis for many years. The extent to which patients had been priory treated with biologic monotherapy and the proportion of patients affected with psoriatic arthritis differed between registries. Survival rates for etanercept, adalimumab, infliximab and ustekinumab with methotrexate ranged between 43 and 92%, 28 and 83%, 65 and 87% and 53 and 77%, respectively, across registries after one year with no consistent superior survival for a particular biologic. Longest survival on a biologic combined with methotrexate, acitretin or cyclosporin was 103, 78 and 34 months, respectively. CONCLUSION: Methotrexate was the most commonly used concomitant treatment for patients on a biologic. Wide geographical variations in treatment selection and persistence of combination treatment exist. Data derived from ongoing studies may help to determine whether combined treatment is superior to biologic monotherapy.


Assuntos
Produtos Biológicos/uso terapêutico , Fármacos Dermatológicos/uso terapêutico , Terapia PUVA , Psoríase/terapia , Acitretina/uso terapêutico , Adalimumab/uso terapêutico , Áustria , Terapia Combinada , Ciclosporina/uso terapêutico , República Tcheca , Quimioterapia Combinada , Etanercepte/uso terapêutico , Feminino , Fumaratos/uso terapêutico , Humanos , Infliximab/uso terapêutico , Israel , Itália , Estimativa de Kaplan-Meier , Masculino , Metotrexato/uso terapêutico , Pessoa de Meia-Idade , Países Baixos , Sistema de Registros , Índice de Gravidade de Doença , Ustekinumab/uso terapêutico
9.
Eur J Orthop Surg Traumatol ; 27(4): 425-431, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28417204

RESUMO

Chopart complex injuries (CCIs) are thought to be uncommon; however, recent literature states the rate of misdiagnosis to be between 20 and 41%. Chopart complex injuries are not ankle injuries, with which they are initially confused due to a similar mechanism of trauma in many cases. Injury to the Chopart complex commonly affects multiple structures. The key to optimal treatment is a high index of clinical suspicion combined with timely accurate imaging studies. Careful diagnostic workup with high-quality radiographs of the foot in neutral position should be obtained. Computed tomography (CT) and/or magnetic resonance imaging (MRI) are recommended to accurately assess bone and soft tissue injury. CCI frequently leads to prolonged swelling, pain and disability. In some cases, it may result in a posttraumatic flatfoot deformity.


Assuntos
Consolidação da Fratura/fisiologia , Fraturas Ósseas/terapia , Articulações Tarsianas/diagnóstico por imagem , Articulações Tarsianas/lesões , Moldes Cirúrgicos , Feminino , Traumatismos do Pé , Fixação Interna de Fraturas/métodos , Fraturas Ósseas/diagnóstico por imagem , Humanos , Escala de Gravidade do Ferimento , Luxações Articulares/diagnóstico por imagem , Luxações Articulares/terapia , Imageamento por Ressonância Magnética/métodos , Masculino , Recuperação de Função Fisiológica , Medição de Risco , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento
10.
Mol Psychiatry ; 20(2): 252-62, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24614496

RESUMO

Amylin, a pancreatic peptide, and amyloid-beta peptides (Aß), a major component of Alzheimer's disease (AD) brain, share similar ß-sheet secondary structures, but it is not known whether pancreatic amylin affects amyloid pathogenesis in the AD brain. Using AD mouse models, we investigated the effects of amylin and its clinical analog, pramlintide, on AD pathogenesis. Surprisingly, chronic intraperitoneal (i.p.) injection of AD animals with either amylin or pramlintide reduces the amyloid burden as well as lowers the concentrations of Aß in the brain. These treatments significantly improve their learning and memory assessed by two behavioral tests, Y maze and Morris water maze. Both amylin and pramlintide treatments increase the concentrations of Aß1-42 in cerebral spinal fluid (CSF). A single i.p. injection of either peptide also induces a surge of Aß in the serum, the magnitude of which is proportionate to the amount of Aß in brain tissue. One intracerebroventricular injection of amylin induces a more significant surge in serum Aß than one i.p. injection of the peptide. In 330 human plasma samples, a positive association between amylin and Aß1-42 as well as Aß1-40 is found only in patients with AD or amnestic mild cognitive impairment. As amylin readily crosses the blood-brain barrier, our study demonstrates that peripheral amylin's action on the central nervous system results in translocation of Aß from the brain into the CSF and blood that could be an explanation for a positive relationship between amylin and Aß in blood. As naturally occurring amylin may play a role in regulating Aß in brain, amylin class peptides may provide a new avenue for both treatment and diagnosis of AD.


Assuntos
Doença de Alzheimer/complicações , Agonistas dos Receptores da Amilina/uso terapêutico , Polipeptídeo Amiloide das Ilhotas Pancreáticas/uso terapêutico , Transtornos Mentais/tratamento farmacológico , Transtornos Mentais/etiologia , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Animais , Ácido Aspártico Endopeptidases/metabolismo , Modelos Animais de Doenças , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/genética , Humanos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mutação/genética , Fragmentos de Peptídeos/metabolismo , Presenilina-1/genética , Escalas de Graduação Psiquiátrica
11.
Br J Dermatol ; 185(2): 470-471, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33949678
14.
Z Geburtshilfe Neonatol ; 220(6): 262-264, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27540980

RESUMO

A fetal epidural hematoma is a rare finding during the prenatal period, with different etiologies such as maternal trauma, infections, or maternal use of specific medications such as warfarin. Both ultrasonography and magnetic resonance imaging (MRI) have been used successfully to evaluate the fetal central nervous system. Although these methods are also useful in detecting and evaluating a fetal epidural hematoma, brain function of the neonate cannot be exactly predicted on the basis of the prenatal findings. According to the literature data to date, this is the first reported case of prenatally detected fetal epidural hematoma of unknown etiology with a good outcome.


Assuntos
Hematoma Epidural Craniano/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Ultrassonografia Pré-Natal/métodos , Adulto , Diagnóstico Diferencial , Feminino , Humanos , Gravidez
15.
Osteoarthritis Cartilage ; 23(3): 363-9, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25463444

RESUMO

OBJECTIVE: To assess reliability and construct validity of the Kellgren-Lawrence (K&L) scale in posttraumatic ankle osteoarthritis (OA); additionally evaluate the validity of including tibiotalar tilting in the scale. METHOD: One-hundred and fifty ankle radiographs (75 patients, unilateral malleolar fractures) evaluated at average of 18 years after surgery. American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot (HF) score and pain (visual analog scale) were recorded. Grading of OA according to K&L criteria and identification of OA features was performed on standardized radiographs by four physicians. Minimal joint space width, sclerosis, and talar tilt angle were quantified by digital measurements. A modified K&L scale including talar tilting is presented. Validity of original and modified scale was evaluated and expressed as ability to (1) Identify those with clinical symptoms of ankle OA; and (2) Distinguish between different degrees of fracture severity. RESULTS: Inter- and intra-observer reliability of OA assessment according to K&L were good (ICC 0.61 and 0.75). Original and modified K&L grades significantly increased with decreasing AOFAS ankle-HF scores and greater pain. A talar-tilt angle > 2° compared with ≤ 2° in grade 3 was associated with significantly higher pain levels (VAS pain 4.2 vs 1.4, respectively; mean difference 2.8, 95% CI 0.5-5.1). More severe fracture patterns at time of surgery were more often in patients with the highest K&L grades. CONCLUSIONS: The K&L scale is a valid and reliable radiographic grading system for assessment of ankle OA. Inclusion of the talar tilt angle might allow for better differentiation with respect to clinical outcomes.


Assuntos
Fraturas do Tornozelo/complicações , Articulação do Tornozelo/diagnóstico por imagem , Osteoartrite/diagnóstico por imagem , Osteófito/diagnóstico por imagem , Tálus/diagnóstico por imagem , Tíbia/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Fraturas do Tornozelo/cirurgia , Estudos de Coortes , Feminino , Seguimentos , Fixação Interna de Fraturas , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite/etiologia , Osteoartrite/fisiopatologia , Medição da Dor , Radiografia , Reprodutibilidade dos Testes
16.
Antimicrob Agents Chemother ; 57(6): 2541-9, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23507287

RESUMO

Agaricus brasiliensis (syn. A. subrufescens), a basidiomycete fungus native to the Atlantic forest in Brazil, contains cell walls rich in glucomannan polysaccharides. The ß-(1 → 2)-gluco-ß-(1 → 3)-mannan was isolated from A. brasiliensis mycelium, chemically modified by sulfation, and named MI-S. MI-S has multiple mechanisms of action, including inhibition of herpes simplex virus (HSV) attachment, entry, and cell-to-cell spread (F. T. G. S. Cardozo, C. M. Camelini, A. Mascarello, M. J. Rossi, R. J. Nunes, C. R. Barardi, M. M. de Mendonça, and C. M. O. Simões, Antiviral Res. 92:108-114, 2011). The antiherpetic efficacy of MI-S was assessed in murine ocular, cutaneous, and genital infection models of HSV. Groups of 10 mice were infected with HSV-1 (strain KOS) or HSV-2 (strain 333). MI-S was given either topically or by oral gavage under various pre- and posttreatment regimens, and the severity of disease and viral titers in ocular and vaginal samples were determined. No toxicity was observed in the uninfected groups treated with MI-S. The topical and oral treatments with MI-S were not effective in reducing ocular disease. Topical application of MI-S on skin lesions was also not effective, but cutaneously infected mice treated orally with MI-S had significantly reduced disease scores (P < 0.05) after day 9, suggesting that healing was accelerated. Vaginal administration of MI-S 20 min before viral challenge reduced the mean disease scores on days 5 to 9 (P < 0.05), viral titers on day 1 (P < 0.05), and mortality (P < 0.0001) in comparison to the control groups (untreated and vehicle treated). These results show that MI-S may be useful as an oral agent to reduce the severity of HSV cutaneous and mucosal lesions and, more importantly, as a microbicide to block sexual transmission of HSV-2 genital infections.


Assuntos
Agaricus/química , Antivirais/uso terapêutico , Polissacarídeos Fúngicos/farmacologia , Herpes Simples/tratamento farmacológico , Herpesvirus Humano 1/efeitos dos fármacos , Herpesvirus Humano 2/efeitos dos fármacos , Animais , Antivirais/farmacologia , Chlorocebus aethiops , Feminino , Polissacarídeos Fúngicos/química , Herpes Genital/tratamento farmacológico , Herpes Genital/virologia , Herpes Simples/virologia , Humanos , Ceratite Herpética/tratamento farmacológico , Ceratite Herpética/virologia , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana/métodos , Sulfatos , Resultado do Tratamento , Células Vero
18.
J Afr Earth Sci ; 86: 65-106, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27065752

RESUMO

The East African Orogen, extending from southern Israel, Sinai and Jordan in the north to Mozambique and Madagascar in the south, is the world́s largest Neoproterozoic to Cambrian orogenic complex. It comprises a collage of individual oceanic domains and continental fragments between the Archean Sahara-Congo-Kalahari Cratons in the west and Neoproterozoic India in the east. Orogen consolidation was achieved during distinct phases of orogeny between ∼850 and 550 Ma. The northern part of the orogen, the Arabian-Nubian Shield, is predominantly juvenile Neoproterozoic crust that formed in and adjacent to the Mozambique Ocean. The ocean closed during a protracted period of island-arc and microcontinent accretion between ∼850 and 620 Ma. To the south of the Arabian Nubian Shield, the Eastern Granulite-Cabo Delgado Nappe Complex of southern Kenya, Tanzania and Mozambique was an extended crust that formed adjacent to theMozambique Ocean and experienced a ∼650-620 Ma granulite-facies metamorphism. Completion of the nappe assembly around 620 Ma is defined as the East African Orogeny and was related to closure of the Mozambique Ocean. Oceans persisted after 620 Ma between East Antarctica, India, southern parts of the Congo-Tanzania-Bangweulu Cratons and the Zimbabwe-Kalahari Craton. They closed during the ∼600-500 Ma Kuungan or Malagasy Orogeny, a tectonothermal event that affected large portions of southern Tanzania, Zambia, Malawi, Mozambique, Madagascar and Antarctica. The East African and Kuungan Orogenies were followed by phases of post-orogenic extension. Early ∼600-550 Ma extension is recorded in the Arabian-Nubian Shield and the Eastern Granulite-Cabo Delgado Nappe Complex. Later ∼550-480 Ma extension affected Mozambique and southern Madagascar. Both extension phases, although diachronous,are interpreted as the result of lithospheric delamination. Along the strike of the East African Orogen, different geodynamic settings resulted in the evolution of distinctly different orogen styles. The Arabian-Nubian Shield is an accretion-type orogen comprising a stack of thin-skinned nappes resulting from the oblique convergence of bounding plates. The Eastern Granulite-Cabo Delgado Nappe Complex is interpreted as a hot- to ultra-hot orogen that evolved from a formerly extended crust. Low viscosity lower crust resisted one-sided subduction, instead a sagduction-type orogen developed. The regions of Tanzania and Madagascar affected by the Kuungan Orogeny are considered a Himalayan-type orogen composed of partly doubly thickened crust.

19.
Sci Rep ; 13(1): 9733, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37322072

RESUMO

Mount Elbrus, Europe's tallest and largely glaciated volcano, is made of silicic lavas and is known for Holocene eruptions, but the size and state of its magma chamber remain poorly constrained. We report high spatial resolution U-Th-Pb zircon ages, co-registered with oxygen and hafnium isotopic values, span ~ 0.6 Ma in each lava, documenting magmatic initiation that forms the current edifice. The best-fit thermochemical modeling constrains magmatic fluxes at 1.2 km3/1000 year by hot (900 °C), initially zircon-undersaturated dacite into a vertically extensive magma body since ~ 0.6 Ma, whereas a volcanic episode with eruptible magma only extends over the past 0.2 Ma, matching the age of oldest lavas. Simulations explain the total magma volume of ~ 180 km3, temporally oscillating δ18O and εHf values, and a wide range of zircon age distributions in each sample. These data provide insights into the current state (~ 200 km3 of melt in a vertically extensive system) and the potential for future activity of Elbrus calling for much-needed seismic imaging. Similar zircon records worldwide require continuous intrusive activity by magmatic accretion of silicic magmas generated at depths, and that zircon ages do not reflect eruption ages but predate them by ~ 103 to 105 years reflecting protracted dissolution-crystallization histories.


Assuntos
Exantema , Resolução de Problemas , Humanos , Cognição , Federação Russa , Silicatos
20.
Pharmacogenomics J ; 12(2): 96-104, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21221126

RESUMO

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are rare but severe, potentially life threatening adverse drug reactions characterized by skin blistering. Previous studies have identified drug-specific and population-specific genetic risk factors with large effects. In this study, we report the first genome-wide association study (GWAS) of SJS/TEN induced by a variety of drugs. Our aim was to identify common genetic risk factors with large effects on SJS/TEN risk. We conducted a genome-wide analysis of 96 retrospective cases and 198 controls with a panel of over one million single-nucleotide polymorphisms (SNPs). We further improved power with about 4000 additional controls from publicly available datasets. No genome-wide significant associations with SNPs or copy number variants were observed, although several genomic regions were suggested that may have a role in predisposing to drug-induced SJS/TEN. Our GWAS did not find common, highly penetrant genetic risk factors responsible for SJS/TEN events in the cases selected.


Assuntos
Estudo de Associação Genômica Ampla , Síndrome de Stevens-Johnson/induzido quimicamente , Síndrome de Stevens-Johnson/etiologia , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Humanos , Masculino , Análise de Componente Principal , Estudos Retrospectivos , Síndrome de Stevens-Johnson/genética
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