Optimization of a synthetic mixture composed of major Trichoderma reesei enzymes for the hydrolysis of steam-exploded wheat straw

<p>Abstract</p> <p>Background</p> <p>An efficient hydrolysis of lignocellulosic substrates to soluble sugars for biofuel production necessitates the interplay and synergistic interaction of multiple enzymes. An optimized enzyme mixture is crucial for reduced cost of the enzymatic hydrolysis step in a bioethanol production process and its composition will depend on the substrate and type of pretreatment used. In the present study, an experimental design was used to determine the optimal composition of a <it>Trichoderma reesei </it>enzyme mixture, comprising the main cellulase and hemicellulase activities, for the hydrolysis of steam-exploded wheat straw.</p> <p>Methods</p> <p>Six enzymes, CBH1 (Cel7a), CBH2 (Cel6a), EG1 (Cel7b), EG2 (Cel5a), as well as the xyloglucanase Cel74a and the xylanase XYN1 (Xyl11a) were purified from a <it>T. reesei </it>culture under lactose/xylose-induced conditions. Sugar release was followed in milliliter-scale hydrolysis assays for 48 hours and the influence of the mixture on initial conversion rates and final yields is assessed.</p> <p>Results</p> <p>The developed model could show that both responses were strongly correlated. Model predictions suggest that optimal hydrolysis yields can be obtained over a wide range of CBH1 to CBH2 ratios, but necessitates a high proportion of EG1 (13% to 25%) which cannot be replaced by EG2. Whereas 5% to 10% of the latter enzyme and a xylanase content above 6% are required for highest yields, these enzymes are predicted to be less important in the initial stage of hydrolysis.</p> <p>Conclusions</p> <p>The developed model could reliably predict hydrolysis yields of enzyme mixtures in the studied domain and highlighted the importance of the respective enzyme components in both the initial and the final hydrolysis phase of steam-exploded wheat straw.</p

Comparative kinetic analysis of two fungal β-glucosidases

<p>Abstract</p> <p>Background</p> <p>The enzymatic hydrolysis of cellulose is still considered as one of the main limiting steps of the biological production of biofuels from lignocellulosic biomass. It is a complex multistep process, and various kinetic models have been proposed. The cellulase enzymatic cocktail secreted by <it>Trichoderma reesei </it>has been intensively investigated. β-glucosidases are one of a number of cellulolytic enzymes, and catalyze the last step releasing glucose from the inhibitory cellobiose. β-glucosidase (BGL1) is very poorly secreted by <it>Trichoderma reesei </it>strains, and complete hydrolysis of cellulose often requires supplementation with a commercial β-glucosidase preparation such as that from <it>Aspergillus niger </it>(Novozymes SP188). Surprisingly, kinetic modeling of β-glucosidases lacks reliable data, and the possible differences between native <it>T. reesei </it>and supplemented β-glucosidases are not taken into consideration, possibly because of the difficulty of purifying BGL1.</p> <p>Results</p> <p>A comparative kinetic analysis of β-glucosidase from <it>Aspergillus niger </it>and BGL1 from <it>Trichoderma reesei</it>, purified using a new and efficient fast protein liquid chromatography protocol, was performed. This purification is characterized by two major steps, including the adsorption of the major cellulases onto crystalline cellulose, and a final purification factor of 53. Quantitative analysis of the resulting β-glucosidase fraction from <it>T. reesei </it>showed it to be 95% pure. Kinetic parameters were determined using cellobiose and a chromogenic artificial substrate. A new method allowing easy and rapid determination of the kinetic parameters was also developed. β-Glucosidase SP188 (K_m= 0.57 mM; K_p= 2.70 mM) has a lower specific activity than BGL1 (K_m= 0.38 mM; K_p= 3.25 mM) and is also more sensitive to glucose inhibition. A Michaelis-Menten model integrating competitive inhibition by the product (glucose) has been validated and is able to predict the β-glucosidase activity of both enzymes.</p> <p>Conclusions</p> <p>This article provides a useful comparison between the activity of β-glucosidases from two different fungi, and shows the importance of fully characterizing both enzymes. A Michaelis-Menten model was developed, including glucose inhibition and kinetic parameters, which were accurately determined and compared. This model can be further integrated into a cellulose hydrolysis model dissociating β-glucosidase activity from that of other cellulases. It can also help to define the optimal enzymatic cocktails for new β-glucosidase activities.</p

The length and depth of real algebraic groups

Let $G$ be a connected real algebraic group. An unrefinable chain of $G$ is a chain of subgroups $G=G_0>G_1>...>G_t=1$ where each $G_i$ is a maximal connected real subgroup of $G_{i-1}$. The maximal (respectively, minimal) length of such an unrefinable chain is called the length (respectively, depth) of $G$. We give a precise formula for the length of $G$, which generalises results of Burness, Liebeck and Shalev on complex algebraic groups and also on compact Lie groups. If $G$ is simple then we bound the depth of $G$ above and below, and in many cases we compute the exact value. In particular, the depth of any simple $G$ is at most $9$

Perfil epidemiológico da Covid-19 em um município do interior do Estado de São Paulo

Since the description of the first cases of Covid-19 in China in December 2019, the disease has spread rapidly across the globe. In Brazil, the first case was described in late February 2020, in the state of São Paulo, becoming the first country in South America to notify a case of Covid-19. The disease spread quickly through the interior of the country, reaching all cities in a short time. In Catanduva, a medium-sized city in the northwest region of São Paulo, the first cases were identified at the end of March 2020. This study aims to demonstrate some epidemiological aspects of the behavior of the pandemic in a medium-sized municipality from Sao Paulo. METHOD: descriptive cross-sectional study. Data were obtained on the clinical and epidemiological profile of patients diagnosed with Covid-19 and residing in the city of Catanduva, from March to December 2020. Data were obtained from the e-SUS and Information System of the Epidemiological Surveillance (SIVEP), provided by the Municipal Health Department. The research was approved by the Research Ethics Committee (CEP) of Centro Universitário Padre Albino with protocol number 4,871,572. RESULTS: In the selected period, 5705 cases of Covid-19 were reported, with 5122 classified as mild cases and 583 as severe cases (SRAG). Among the severe cases, 186 evolved to death. The mean age were different when comparing the groups, with the most severe cases showing higher means. Females predominated in mild cases and males in severe cases and deaths. The most frequent symptoms were fever, cough, dyspnea and odynophagia. Comorbidities such as heart disease, diabetes, obesity and lung disease were more frequent, especially among severe cases and deaths. Among hospitalized patients, the death rate was 32.1%. This rate increases to 50.5% for patients who required intensive care and to 79.2% for patients who required orotracheal intubation. CONCLUSION: The results presented in the present study are in accordance with the findings in the literature and demonstrate the impact the pandemic has had on the health of the population.Desde a descrição dos primeiros casos de Covid-19 na China em dezembro de 2019, a doença se espalhou rapidamente por todo o globo. No Brasil o primeiro caso foi descrito no final de fevereiro de 2020, no estado de São Paulo, tornando-se o primeiro país da América do Sul a notificar um caso de Covid-19. Rapidamente a doença se disseminou pelo interior do país, atingindo em pouco tempo praticamente todas as cidades. Em Catanduva, cidade de médio porte da região noroeste paulista, os primeiros casos foram identificados no final do mês de março de 2020. Esse estudo tem o objetivo de demonstrar alguns aspectos epidemiológicos do comportamento da pandemia em um município de médio porte do interior do estado de São Paulo. MÉTODO: estudo descritivo transversal. Foram obtidos dados sobre o perfil clínico e epidemiológico dos pacientes diagnosticados com Covid-19 e residentes na cidade de Catanduva, no período de março a dezembro de 2020. Os dados foram obtidos dos bancos de dados e-SUS e Sistema de Informação da Vigilância Epidemiológica (SIVEP), fornecidos pela Secretaria de Saúde do município. A pesquisa foi aprovada pelo Comitê de Ética e Pesquisa (CEP) do Centro Universitário Padre Albino com número do protocolo 4.871.572. RESULTADOS: No período selecionado, foram notificados 5705 casos de Covid-19, sendo 5122 classificados como casos leves e 583 como casos graves (SRAG). Dentre os casos graves 186 evoluíram para óbito. A média de idade e a mediana foram diferentes na comparação entre os grupos, com os casos mais graves mostrando médias mais altas. Sexo feminino predominou nos casos leves e o masculino nos casos graves e óbitos. Os sintomas mais frequentes foram febre, tosse, dispneia e odinofagia. Comorbidades como cardiopatias, diabetes, obesidade e pneumopatias foram mais frequentes principalmente entre os casos graves e óbitos. Dentre os pacientes internados a taxa de óbito foi de 32,1%. Essa taxa aumenta para 50,5% para os pacientes que necessitaram de terapia intensiva e para 79,2% para os pacientes que necessitaram de intubação orotraqueal. CONCLUSÃO: os resultados apresentados no presente estudo se mostraram em conformidade com os achados na literatura e demonstraram o impacto que a pandemia causou e tem causado na saúde da população

Síndrome de guillain-barré e encefalite de bickerstaff na gravidez / Guillain-barré syndrome and bickerstaff encephalitis in pregnancy

A Síndrome de Guillain-Barré (SGB) é a maior causa da paralisia flácida generalizada no mundo, com incidência anual de 1 a 2 casos por 100.000 habitantes, com pico entre 20 e 40 anos de idade. Apresenta-se como uma neuropatia periférica inflamatória adquirida, de início agudo, monofásica e de caráter autoimune.Aproximadamente 60% a 70% dos pacientes com SGB apresentam alguma doença aguda como infecções, intervenções cirúrgicas e mais problemáticas, como no caso relatado. Esse relato expõe o caso de uma paciente grávida que desenvolve um quadro de encefalite concomitante à SGB e seu quadro típico através da análise de prontuário.Mulher, 26 anos, previamente hígida, há 5 anos iniciada durante o segundo mês de gestação quadro de fraqueza em membros inferiores, de forma ascendente, que evoluiu com ataxia de marcha, cefaleia, turvamento visual e perda de memória. À época, o diagnóstico estabelecido foi de Síndrome de Guillain-Barré através do histórico, exame físico, avaliação do líquido cefalorraquidiano (LCR) e pelos resultados da eletroneuromiografia do paciente. Due contraindicação obstétrica, não foi administrado imunoglobulina intravenosa (IgIV). Ao resultado disso, ocorreu o pulso de corticoide, porém não houve melhora da motricidade, ocorrendo a instalação da forma crônica da neuropatia. Após o parto, foi iniciado o tratamento com IgIV 0,4g / kg / dia por 5 dias, sendo realizada mais 4 doses posteriormente, ocorrendo satisfatória melhora motora.Recentemente, através de uma análise mais detalhada, foi definido o diagnóstico de Espectro da Síndrome de Guillain-Barré, que envolve uma Neuropatia Axonal Sensório-motora Aguda (AMSAN) e critérios desmielinizantes comum à Polirradiculoneuropatia Desmielinizante Inflamatória Aguda (ADIP), associado à Encefalita de Bickerstaff. Atualmente a doença manifesta-se de forma mais branda, com intensa melhora dos sintomas, porém ainda apresenta nível de ataxia e déficit de memória.  Dessa forma, é importante que os médicos incluam SGB em seus diagnósticos diferenciais de forma que o tratamento seja instituído em tempo hábil para evitar casos de cronificação como no relato descrito

II Diretriz Brasileira de Transplante Cardíaco

Universidade de São Paulo Faculdade de Medicina Hospital das ClínicasIIHospital de Messejana Dr. Carlos Alberto Studart GomesUniversidade Federal de São Paulo (UNIFESP) Escola Paulista de MedicinaInstituto Dante Pazzanese de CardiologiaUniversidade Federal de Minas Gerais Hospital das ClínicasFaculdade de Medicina de São José do Rio PretoPontifícia Universidade Católica do ParanáIHospital Israelita Albert EinsteinInstituto Nacional de Cardiologia, Fundação Universitária do Rio Grande do Sul Instituto de CardiologiaReal e Benemérita Sociedade de Beneficência Portuguesa, São PauloHospital Pró-Cardíaco do Rio de JaneiroSanta Casa do Rio de JaneiroUNIFESP, EPMSciEL

MIOMATOSE CLÍNICA E SUAS REPERCUSSÕES REVISÃO DE LITERATURA

Uterine leiomyoma, known as myoma, is a benign tumor that affects a significant proportion of women of reproductive age. Its high incidence, which can reach 40%, makes this condition a relevant medical and social challenge. Its origin is related to the clonal expansion of a single cell in the uterine myometrium, although the exact pathogenetic mechanisms are not yet fully understood. This study presents an integrative analysis with the aim of discussing the possibilities of clinical and surgical treatment for uterine fibroids, addressing aspects of the pathology to contribute to the knowledge of society, students and professionals in the field. The research was carried out in databases and there is no proof of the effectiveness of oral contraceptives in the treatment of fibroids. However, they are useful in controlling dysfunctional uterine bleeding. Definitive treatment for symptomatic fibroids is usually surgical, with hysterectomy being one of the main options. In summary, uterine fibroids are common and can significantly impact women's quality of life. Medical and surgical treatment options offer diverse therapeutic approaches, each with specific advantages and considerations.O leiomioma uterino, conhecido como mioma, é um tumor benigno que afeta uma parcela significativa das mulheres em idade reprodutiva. Sua alta incidência, que pode chegar a 40%, torna essa condição um desafio médico e social relevante. Sua origem está relacionada à expansão clonal de uma única célula no miométrio uterino, embora os mecanismos patogenéticos exatos ainda não estejam totalmente esclarecidos. Este estudo apresenta uma análise integrativa com o objetivo de discutir as possibilidades de tratamento clínico e cirúrgico para miomas uterinos, abordando aspectos da patologia para contribuir com o conhecimento da sociedade, estudantes e profissionais da área. A pesquisa foi realizada em bases de dados e não há comprovação da eficácia dos contraceptivos orais no tratamento dos miomas. No entanto, eles são úteis no controle do sangramento uterino disfuncional. O tratamento definitivo para miomas sintomáticos geralmente é cirúrgico, sendo a histerectomia uma das principais opções. Em resumo, os miomas uterinos são comuns e podem impactar significativamente a qualidade de vida das mulheres. As opções de tratamento clínico e cirúrgico oferecem diversas abordagens terapêuticas, cada uma com vantagens e considerações específicas

Search for the standard model Higgs boson in the H to ZZ to 2l 2nu channel in pp collisions at sqrt(s) = 7 TeV

A search for the standard model Higgs boson in the H to ZZ to 2l 2nu decay channel, where l = e or mu, in pp collisions at a center-of-mass energy of 7 TeV is presented. The data were collected at the LHC, with the CMS detector, and correspond to an integrated luminosity of 4.6 inverse femtobarns. No significant excess is observed above the background expectation, and upper limits are set on the Higgs boson production cross section. The presence of the standard model Higgs boson with a mass in the 270-440 GeV range is excluded at 95% confidence level.Comment: Submitted to JHE

Combined search for the quarks of a sequential fourth generation

Results are presented from a search for a fourth generation of quarks produced singly or in pairs in a data set corresponding to an integrated luminosity of 5 inverse femtobarns recorded by the CMS experiment at the LHC in 2011. A novel strategy has been developed for a combined search for quarks of the up and down type in decay channels with at least one isolated muon or electron. Limits on the mass of the fourth-generation quarks and the relevant Cabibbo-Kobayashi-Maskawa matrix elements are derived in the context of a simple extension of the standard model with a sequential fourth generation of fermions. The existence of mass-degenerate fourth-generation quarks with masses below 685 GeV is excluded at 95% confidence level for minimal off-diagonal mixing between the third- and the fourth-generation quarks. With a mass difference of 25 GeV between the quark masses, the obtained limit on the masses of the fourth-generation quarks shifts by about +/- 20 GeV. These results significantly reduce the allowed parameter space for a fourth generation of fermions.Comment: Replaced with published version. Added journal reference and DO

Search for a W' boson decaying to a bottom quark and a top quark in pp collisions at sqrt(s) = 7 TeV

Results are presented from a search for a W' boson using a dataset corresponding to 5.0 inverse femtobarns of integrated luminosity collected during 2011 by the CMS experiment at the LHC in pp collisions at sqrt(s)=7 TeV. The W' boson is modeled as a heavy W boson, but different scenarios for the couplings to fermions are considered, involving both left-handed and right-handed chiral projections of the fermions, as well as an arbitrary mixture of the two. The search is performed in the decay channel W' to t b, leading to a final state signature with a single lepton (e, mu), missing transverse energy, and jets, at least one of which is tagged as a b-jet. A W' boson that couples to fermions with the same coupling constant as the W, but to the right-handed rather than left-handed chiral projections, is excluded for masses below 1.85 TeV at the 95% confidence level. For the first time using LHC data, constraints on the W' gauge coupling for a set of left- and right-handed coupling combinations have been placed. These results represent a significant improvement over previously published limits.Comment: Submitted to Physics Letters B. Replaced with version publishe