IL-4 and TAL1 in T-cell acute lymphoblastic leukemia : studies on the participation of microenvironmental cues and cell-autonomous alterations in leukemogenesis

Tese de doutoramento, Ciências Biomédicas (Ciências Morfológicas), Universidade de Lisboa, Faculdade de Medicina, 2011Acute lymphoblastic leukemia (ALL) is the most frequent cancer found in children and results from the clonal expansion of transformed lymphoid precursors. Approximately 15% of pediatric ALL patients present with a T-cell phenotype (T-ALL). Despite the recent improvements in the treatment of T-ALL, there are still a high number of relapses and the intensive chemotherapeutic regiments used are associated with long-term severe complications. In order to develop new therapeutic strategies that can further increase efficacy while reducing side effects, one needs to better understand the pathobiology of T-ALL. In particular, it is necessary to understand how microenvironmental and cell-autonomous mechanisms influence the initiation and the progression of leukemia. The present thesis has the preocupation of exploring the mechanisms by which both an extracellular cue (IL-4) and a cell-intrinsic transcription factor (TAL1) may partake in leukemia development and maintenance. Interleukin-4 (IL-4) is a γ-common chain cytokine produced within the bone marrow microenvironment that is known to promote the in vitro proliferation of T-ALL cells. In Chapter 2, we present evidence that IL-4 induces primary T-ALL cell cycle progression from G0/G1 into S and G2/M, by up-regulating cyclin D2, E and A and down-regulating the cyclin-dependent kinase inhibitor p27kip1. Transfection of T-ALL cells with the VP22-p27kip1 fusion protein, which is able to translocate into the cytoplasm and nucleus of target cells, abrogates IL-4-mediated proliferation. This indicates that p27kip1 downregulation is mandatory for cell cycle progression of T-ALL cells stimulated with IL-4. Furthermore, IL-4 stimulates mTOR activation, as determined by increased phosphorylation of its downstream targets p70S6K, S6 and 4E-BP1. Inhibition of mTOR signaling with rapamycin prevents IL-4-induced T-ALL cell growth, cell cycle progression and proliferation. Our results identify mTOR as a critical regulator of IL-4-mediated effects in T-ALL cells and support the rationale for using mTOR pharmacological inhibitors in T-ALL therapy (Cardoso et al. Leukemia 2009). The basic helix-loop-helix transcription factor TAL1 is aberrantly expressed in up to 65% of T-ALL patients. LMO2, a Lim-only domain protein, is often co-expressed ectopically with TAL1 in this malignancy. These genes appear to have leukemogenic potential, since both TAL1 and LMO2 transgenic mice develop leukemias of T-cell phenotype. However, it is still unclear whether TAL1 is effectively leukemogenic in humans, or whether merely participates as a secondary event in the transformation Abstract xiii process in T-ALL. To address this question, we transduced hematopoietic progenitors with TAL1 and/or LMO2 and co-cultured them with OP9-Dll1 stromal cells, which have the capacity to induce T-cell differentiation in vitro. We found that TAL1 and LMO2 genes deregulate human T-cell differentiation in stromal cell co-cultures. Interestingly, the coordinated expression of both TAL1 and LMO2 led to a relative increase in CD3+CD4+CD8+ T-cell precursors with increased cell size. This observation is particularly interesting given that TAL1-expressing patients normally display a similar phenotype. These preliminary results show that TAL1 and LMO2 can disrupt normal human T-cell development, therefore likely predisposing thymocytes to malignant transformation (Chapter 3). In our effort to characterize the mechanisms by which TAL1 might promote T-cell leukemogenesis, we developed a TAL1 inducible system, by fusing TAL1 with the hormone binding domain (HBD) of the estrogen receptor (ER), which we expressed in a TAL1-negative T-cell line. Upon 4-Hydroxi-Tamoxifen (4OHT) treatment, ER-TAL1 fusion protein is able to translocate into the nucleus and consequently trigger its transcriptional program. Gene expression profiling of 4OHT-treated HPB-ALL cells stably transduced with the ER-TAL1 fusion revealed a total of 26 genes up- or down-regulated by TAL1 activation, in at least two independent experiments. We selected seven of those genes on the basis of their function/potential interest in cancer and confirmed the differential expression of three (CASZ1, DMGDH and OR5M3) by qRT-PCR. Accordingly, transfection of another TAL1-negative T-ALL cell line, P12, with TAL1, also led to increased expression of the validated TAL1 target genes. The possible involvement of CASZ1 in TAL1-mediated anti-apoptotic and proliferative effects in T-ALL cells was subsequently investigated. Knock-down of TAL1 with siRNA in the TAL1-positive T-ALL cell line Jurkat decreased the expression of CASZ1, correlating with loss of cell viability. Moreover, CASZ1 knockdown in Jurkat cells led to functional effects similar to those of TAL1 knockdown, namely a decrease in survival and proliferation. Overall, these studies allowed the identification of three novel TAL1 downstream targets, likely with functional relevance for TAL1-mediated leukemogenic potential (Chapter 4). TAL1 binds to repressive chromatin complexes, namely involving HDAC1, and incubation with HDAC inhibitors (HDACis) promotes apoptosis of leukemia cells derived from TAL1 transgenic mice. In Chapter 5, we evaluated the impact of HDACis on TAL1 from a somewhat different perspective, namely by analyzing their impact on Abstract xiv TAL1 expression rather than transcriptional activity. We found that incubation of T-ALL cells with HDACis strikingly down-regulates TAL1 protein expression. This is due to decreased TAL1 gene transcription in cells with an intact TAL1 locus, and to impaired TAL1 mRNA translation in cells that harbor the TAL1d deletion. Importantly, HDACi-induced apoptosis of T-ALL cells is significantly reversed by TAL1 forced over-expression. Our results indicate that the HDACi-mediated apoptotic program in T-ALL cells is partially dependent on the down-regulation of TAL1 expression, and suggest that integration of HDACis into T-ALL treatment protocol may be of potential therapeutic benefit (Cardoso et al, Leukemia 2011, advance online publication). Taken together, the results described in this thesis highlight the importance that microenviromental factors, such as IL-4, might have in the progression of T-ALL (for instance, by activating mTOR and promoting cell cycle progression), and hint on the importance that cell-autonomous factors, such as TAL1 and LMO2, may have in predisposing T-cells for malignant transformation and promoting survival of T-ALL cells. Importantly, our results further demonstrate that both extracellular cues and intracellular molecular lesions can constitute targets for therapeutic intervention in T-ALL.A Leucemia Linfoblástica Aguda (LLA) é o cancro mais frequente em crianças, resultando da expansão clonal maligna de precursores linfóides. Aproximadamente 15% dos doentes com LLA apresentam marcadores de células T (LLA-T). Embora os regimes quimioterápicos actualmente em uso sejam bastante eficazes, existe ainda um número significativo de doentes que recidivam. Além disso, os regimes intensivos de quimioterapia estão normalmente associados a efeitos secundários consideráveis a médio e longo prazo. Para melhor perceber a biologia da LLA-T e determinar novos alvos terapêuticos é necessário perceber em que medida factores microambientais e mecanismos intra-celulares influenciam a génese e a progressão da leucemia. A presente tese procura identificar os mecanismos pelos quais tanto um factor extracelular (IL-4) como um factor de transcrição celular (TAL1) podem participar no desenvolvimento e progressão da leucemia. A Interleucina-4 (IL-4) é uma citocina da cadeia comum-γ, produzida na medula óssea, que estimula a proliferação in vitro de células LLA-T. No capítulo 2, demonstramos que a IL-4 induz a progressão do ciclo celular da fase G0/G1 para as fases S e G2/M em células LLA-T primárias, devido ao aumento da expressão das ciclinas D2, E e A e à diminuição de expressão do inibidor de cinases dependentes de ciclinas p27Kip1. A transfecção de células LLA-T com a proteína de fusão VP22-p27Kip1, que é capaz de translocar para o citoplasma e núcleo das células alvo, impede a proliferação mediada por IL-4. Além disso, a IL-4 estimula a activação de mTOR, como demonstra o aumento de fosforilação dos seus alvos p70S6K, S6 e 4E-BP1. A inibição da sinalização mediada por mTOR com rapamicina impede o crescimento celular, a progressão do ciclo celular e a proliferação de células LLA-T estimuladas por IL-4. Estes resultados identificam mTOR como um regulador dos efeitos moleculares e celulares promovidos por IL-4 em células LLA-T e fortalecem a hipótese do uso de inibidores farmacológicos de mTOR no tratamento de doentes com LLA-T (Capítulo 2; Cardoso et al. Leukemia 2009). O factor de transcrição hélice-volta-hélice TAL1 é aberrantemente expresso em quase 65% dos doentes com LLA-T. A proteína “Lim-only domain” LMO2, é geralmente co-expressa com TAL1 neste tipo de leucemia. Estes genes parecem contribuir para a génese da leucemia, visto que ratinhos transgénicos para TAL1 e LMO2 desenvolvem leucemia com fenótipo de células T. No entanto, não se confirmou Resumo x até hoje se TAL1 estará envolvido na génese da leucemia em seres humanos, ou apenas secundariamente activado como resultado do processo de transformação em LLA-T. Para responder a esta questão, transduzimos progenitores hematopoiéticos com TAL1 e/ou LMO2 e co-cultivamos estes progenitores com células estromais OP9-Dll1, que têm a capacidade de induzir a diferenciação de células T in vitro. Descobrimos que os genes TAL1 e LMO2 desregulam a diferenciação de células T em co-cultura com células estromais. A expressão coordenada destes dois genes leva a um pequeno aumento de precursores T CD3+CD4+CD8+ de tamanho celular aumentado. Esta observação é particularmente interessante visto que se sabe que os blastos de pacientes com LLA-T que expressam TAL1 apresentam um imunofenótipo idêntico. Estes resultados preliminares mostram que TAL1 e LMO2 podem perturbar o normal desenvolvimento de células T humanas, possivelmente predispondo os timócitos para transformação maligna (Capítulo 3). Com o intuito de identificar e caracterizar os eventuais alvos transcricionais através dos quais TAL1 poderá gerar leucemia de células T, desenvolvemos um sistema indutível em que a fusão de TAL1 com o domínio de ligação a hormonas (DLH) do receptor de estrogénio (RE) permite a regulação fina da actividade de TAL1 numa linha celular T sem expressão de TAL1 endógeno. Após tratamento com 4-Hidróxi-Tamoxifeno (4HT), a proteína de fusão RE-TAL1 consegue translocar para o núcleo celular e consequentemente activar o seu programa de trancrição. O perfil de expressão da linha celular HPB-ALL estavelmente transduzida com a fusão RE-TAL1 e tratada com 4HT revelou um total de 26 genes cuja expressão aumentou ou diminuiu após activação de TAL1, em pelo menos 2 experiências independentes. Seleccionámos sete genes com base na sua função e potencial interesse em cancro e confirmámos a expressão diferencial de três (CASZ1, DMGDH e OR5M3) por PCR quantitativo em tempo real. A transfecção de TAL1 numa outra linha celular LLA-T sem expressão deste gene (P12), resulta igualmente num aumento da expressão destes genes. O possível envolvimento de CASZ1 nos efeitos anti-apoptóticos e proliferativos mediados por TAL1 em células LLA-T também foi investigado. A diminuição da expressão de TAL1 com siRNA na linha celular Jurkat, que expressa TAL1 abundantemente, diminui significativamente a expressão de CASZ1, e a perda de expressão correlacionacom perda de viabilidade celular. Acresce que a diminuição da expressão de CASZ1 em células Jurkat tem efeitos funcionais semelhantes aos que ocorrem após redução da expressão de TAL1, nomeadamente diminuição da viabilidade celular e proliferação. Resumo xi No geral, estes estudos permitiram a identificação de três novos genes alvo de TAL1, com possível relevância funcional no contexto do potencial poder oncogénico de TAL1 (Capítulo 4) TAL1 parece ter não apenas um papel de regulador positivo mas também de repressor da transcrição. Não é, portanto, de surpreender que tenha sido demonstrado anteriormente que TAL1 se pode associar a complexos de cromatina repressivos, nomeadamente HDAC1, e que a incubação com inibidores de HDAC (iHDAC) induz apoptose em células leucémicas derivadas de ratinhos transgénicos para TAL1. No capítulo 5, avaliamos o impacto dos iHDAC em TAL1 numa perspectiva diferente, nomeadamente analisando o seu impacto na expressão de TAL1 e não no impacto na actividade transcricional. Os nossos estudos revelam que a incubação de células LLA-T com iHDAC diminui drasticamente a expressão da proteína TAL1. Este efeito é devido à diminuição da transcrição do gene TAL1 em células que mantêm o locus TAL1 intacto, mas também devido à diminui da tradução de mRNAs TAL1 em células que contêm a delecção TAL1d. Igualmente importante é o facto da apoptose induzida pelos iHDAC ser inibida pela sobre-expressão de TAL1. Os nossos resultados indicam que o programa apoptótico promovido pelos iHDAC em LLA-T é parcialmente dependente da diminuição da expressão de TAL1 e sugerem que a integração de iHDAC no protocolo de tratamento de doentes LLA-T pode trazer benefícios terapêuticos (Cardoso et al, Leukemia 2011, advance online publication). O conjunto dos estudos descritos nesta dissertação destacam a importância que os factores micro-ambientais, como IL-4, podem ter na progressão de LLA-T (por exemplo, activando mTOR e promovendo a progressão no ciclo celular) e mostram a importância que factores celulares como TAL1, e também LMO2, podem ter na predisposição de células T para a transformação maligna e na sobrevivência das células LLA-T. Finalmente, os resultados desta tese demonstram que tanto factores extracelulares como lesões intracelulares podem constituir alvos promissores para intervenção terapêutica em LLA-T

RAC1b overexpression stimulates proliferation and NF-kB-mediated anti-apoptotic signaling in thyroid cancer cells

Overexpression of tumor-associated RAC1b has been recently highlighted as one of the most promising targets for therapeutic intervention in colon, breast, lung and pancreatic cancer. RAC1b is a hyperactive variant of the small GTPase RAC1 and has been recently shown to be overexpressed in a subset of papillary thyroid carcinomas associated with unfavorable outcome. Using the K1 PTC derived cell line as an in vitro model, we observed that both RAC1 and RAC1b were able to induce a significant increase on NF-kB and cyclin D1 reporter activity. A clear p65 nuclear localization was found in cells transfected with RAC1b-WT, confirming NF-kB canonical pathway activation. Consistently, we observed a RAC1b-mediated decrease in IκBα (NF-kB inhibitor) protein levels. Moreover, we show that RAC1b overexpression stimulates G1/S progression and protects thyroid cells against induced apoptosis, the latter through a process involving the NF-kB pathway. Present data support previous findings suggesting an important role for RAC1b in the development of follicular cell-derived thyroid malignancies and point out NF-kB activation as one of the molecular mechanisms associated with the pro-tumorigenic advantage of RAC1b overexpression in thyroid carcinomas.info:eu-repo/semantics/publishedVersio

Increased RPA1 gene dosage affects genomic stability potentially contributing to 17p13.3 duplication syndrome

A novel microduplication syndrome involving various-sized contiguous duplications in 17p13.3 has recently been described, suggesting that increased copy number of genes in 17p13.3, particularly PAFAH1B1, is associated with clinical features including facial dysmorphism, developmental delay, and autism spectrum disorder. We have previously shown that patient-derived cell lines from individuals with haploinsufficiency of RPA1, a gene within 17p13.3, exhibit an impaired ATR-dependent DNA damage response (DDR). Here, we show that cell lines from patients with duplications specifically incorporating RPA1 exhibit a different although characteristic spectrum of DDR defects including abnormal S phase distribution, attenuated DNA double strand break (DSB)-induced RAD51 chromatin retention, elevated genomic instability, and increased sensitivity to DNA damaging agents. Using controlled conditional over-expression of RPA1 in a human model cell system, we also see attenuated DSB-induced RAD51 chromatin retention. Furthermore, we find that transient over-expression of RPA1 can impact on homologous recombination (HR) pathways following DSB formation, favouring engagement in aberrant forms of recombination and repair. Our data identifies unanticipated defects in the DDR associated with duplications in 17p13.3 in humans involving modest RPA1 over-expression

Toward the Mechanistic Understanding of Enzymatic CO2 Reduction

SFRH/BD/116515/2014 PTDC/BBB-EBB/2723/2014 UID/Multi/04378/2019 grant agreement number 810856Reducing CO2 is a challenging chemical transformation that biology solves easily, with high efficiency and specificity. In particular, formate dehydrogenases are of great interest since they reduce CO2 to formate, a valuable chemical fuel and hydrogen storage compound. The metal-dependent formate dehydrogenases of prokaryotes can show high activity for CO2 reduction. Here, we report an expression system to produce recombinant W/Sec-FdhAB from Desulfovibrio vulgaris Hildenborough fully loaded with cofactors, its catalytic characterization and crystal structures in oxidized and reduced states. The enzyme has very high activity for CO2 reduction and displays remarkable oxygen stability. The crystal structure of the formate-reduced enzyme shows Sec still coordinating the tungsten, supporting a mechanism of stable metal coordination during catalysis. Comparison of the oxidized and reduced structures shows significant changes close to the active site. The DvFdhAB is an excellent model for studying catalytic CO2 reduction and probing the mechanism of this conversion.publishersversionpublishe

Transtorno mental comum na gravidez e sintomas depressivos pós-natal no estudo MINA-Brasil: ocorrência e fatores associados

OBJECTIVE To investigate the occurrence and factors associated with common mental disorders in pregnancy and depressive symptoms in postpartum, as well as the association between both in the Brazilian Western Amazon. METHODS This is a prospective cohort in the MINA-Brazil study with women who received primary health care in the town of Cruzeiro do Sul, Acre State. We performed two clinical evaluations during pregnancy (the first: 16–20 weeks; the second: 28 gestational weeks) and three postpartum evaluations (at 3, 6 and 12 months), in which demographic and socioeconomic, gestational, lifestyle and clinical data were collected. We used the Self-Reported Questionnaire (score ≥ 8) to screen the gestational common mental disorder and the Edinburgh Postnatal Depression Scale (score ≥ 10) to identify postpartum depressive symptoms. We used adjusted ordinal logistic regression to investigate the relationship between the covariates and the occurrence of common mental disorders in pregnancy and postpartum depressive symptomatology. RESULTS A total of 461 women completed the two clinical evaluations in pregnancy; of these, 247 completed the three postpartum evaluations. The occurrence of common mental disorder during pregnancy was 36.2% and 24.5% in the first and second evaluations, respectively, and the cumulative incidence was 9.2%. In addition, 50.3% maintained the disorder between evaluations. During postpartum, approximately 20% of the mothers presented depressive symptoms during the first year of their children’s lives. Parity (≥ 2) was associated with common mental disorders, while low maternal education was associated with postpartum depressive symptoms. Women with a common mental disorder in both evaluations during pregnancy were 5.6 times more likely (95%CI: 2.50–12.60) to develop postpartum depressive symptoms. CONCLUSION The occurrence of common mental disorder at any time assessed during pregnancy, but especially its persistence from the second trimester, was strongly associated with depressive symptoms after childbirth. These findings highlight the need for early screening and monitoring of the mental health of pregnant women at the start of prenatal care in order to reduce possible negative impacts on the health of the mother-child binomial caused by such events.OBJETIVO Investigar a ocorrência e os fatores associados com os transtornos mentais comuns na gestação e sintomas depressivos no pós-parto, bem como a associação entre ambos na Amazônia Ocidental Brasileira. MÉTODOS Coorte prospectiva no estudo MINA-Brasil com mulheres atendidas na atenção primária à saúde de Cruzeiro do Sul, Acre. Foram realizadas duas avaliações clínicas na gestação (primeira: 16–20 semanas; segunda: 28 semanas gestacionais) e três avaliações no pós-parto (aos 3, 6 e 12 meses), nas quais foram coletados dados demográficos e socioeconômicos, gestacionais, de estilo de vida e clínicos. Utilizou-se o Self-Reported Questionnaire (escore ≥ 8) para rastreamento do transtorno mental comum gestacional e a escala de depressão pós-natal de Edimburgo (escore ≥ 10) para identificação de sintomas depressivos pós-parto. Foi utilizada regressão logística ordinal ajustada para investigar a relação entre as covariáveis e a ocorrência de transtornos mentais comuns na gravidez e a sintomatologia depressiva no pós-parto. RESULTADOS Um total de 461 mulheres completaram as duas avaliações clínicas na gestação; dessas, 247 completaram as três avaliações pós-parto. A ocorrência de transtorno mental comum durante a gestação foi de 36,2% e 24,5% na primeira e segunda avaliações, respectivamente, e a incidência cumulativa foi de 9,2%. Ademais, 50,3% mantiveram o transtorno entre as avaliações. Durante o pós-parto, aproximadamente 20% das mães apresentaram sintomatologia depressiva ao longo do primeiro ano de vida de seus filhos. A paridade (≥ 2) foi associada ao transtorno mental comum, enquanto a baixa escolaridade materna associou-se com sintoma depressivo pós-parto. Mulheres com transtorno mental comum nas duas avaliações na gravidez apresentaram 5,6 vezes mais chance (IC95% 2,50–12,60) de desenvolverem sintoma depressivo pós-parto. CONCLUSÃO A ocorrência de transtorno mental comum em qualquer momento avaliado durante a gravidez, mas principalmente sua persistência a partir do segundo trimestre, foi fortemente associado ao sintoma depressivo posterior ao parto. Tais achados evidenciam a necessidade de rastreamento precoce e monitoramento da saúde mental de gestantes no início do pré-natal, a fim de reduzir possíveis impactos negativos para a saúde do binômio mãe-filho causados por tais eventos

Epigenetic Alterations in Fanconi Anaemia : Role in Pathophysiology and Therapeutic Potential

Fanconi anaemia (FA) is an inherited disorder characterized by chromosomal instability. The phenotype is variable, which raises the possibility that it may be affected by other factors, such as epigenetic modifications. These play an important role in oncogenesis and may be pharmacologically manipulated. Our aim was to explore whether the epigenetic profiles in FA differ from non-FA individuals and whether these could be manipulated to alter the disease phenotype. We compared expression of epigenetic genes and DNA methylation profile of tumour suppressor genes between FA and normal samples. FA samples exhibited decreased expression levels of genes involved in epigenetic regulation and hypomethylation in the promoter regions of tumour suppressor genes. Treatment of FA cells with histone deacetylase inhibitor Vorinostat increased the expression of DNM3Tβ and reduced the levels of CIITA and HDAC9, PAK1, USP16, all involved in different aspects of epigenetic and immune regulation. Given the ability of Vorinostat to modulate epigenetic genes in FA patients, we investigated its functional effects on the FA phenotype. This was assessed by incubating FA cells with Vorinostat and quantifying chromosomal breaks induced by DNA cross-linking agents. Treatment of FA cells with Vorinostat resulted in a significant reduction of aberrant cells (81% on average). Our results suggest that epigenetic mechanisms may play a role in oncogenesis in FA. Epigenetic agents may be helpful in improving the phenotype of FA patients, potentially reducing tumour incidence in this population

Dark Matter Results from 100 Live Days of XENON100 Data

We present results from the direct search for dark matter with the XENON100 detector, installed underground at the Laboratori Nazionali del Gran Sasso of INFN, Italy. XENON100 is a two-phase time projection chamber with a 62 kg liquid xenon target. Interaction vertex reconstruction in three dimensions with millimeter precision allows to select only the innermost 48 kg as ultra-low background fiducial target. In 100.9 live days of data, acquired between January and June 2010, no evidence for dark matter is found. Three candidate events were observed in a pre-defined signal region with an expected background of 1.8 +/- 0.6 events. This leads to the most stringent limit on dark matter interactions today, excluding spin-independent elastic WIMP-nucleon scattering cross-sections above 7.0x10^-45 cm^2 for a WIMP mass of 50 GeV/c^2 at 90% confidence level.Comment: 5 pages, 5 figures; matches accepted versio

Oral paracoccidioidomycosis:a retrospective study of 95 cases from a single center and literature review

The ecoepidemiological panorama of paracoccidioidomycosis (PCM) is dynamic and still ongoing in Brazil. In particular, data about the oral lesions of PCM are barely explored. The aim of this study was to report the clinicopathological features of individuals diagnosed with oral PCM lesions at an oral and maxillofacial pathology service in Rio de Janeiro, Brazil, in the light of a literature review. A retrospective study was conducted on oral biopsies obtained from 1958 to 2021. Additionally, electronic searches were conducted in PubMed, Embase, Scopus, Web of Science, Latin American and Caribbean Center on Health Sciences Information, and Brazilian Library of Dentistry to gather information from large case series of oral PCM. Ninety-five cases of oral PCM were surveyed. The manifestations were more frequent among males (n=86/90.5%), middle-aged/older adults (n=54/58.7%), and white individuals (n=40/51.9%). The most commonly affected sites were the gingiva/alveolar ridge (n=40/23.4%) and lip/labial commissure (n=33/19.3%); however, one (n=40/42.1%) or multiple sites (n=55/57.9%) could also be affected. In 90 (94.7%) patients, ?mulberry-like? ulcerations/moriform appearance were observed. Data from 21 studies (1,333 cases), mostly Brazilian (90.5%), revealed that men (92.4%; male/female: 11.8:1) and individuals in the fifth and sixth decades of life were the most affected (range: 7-89 years), with the gingiva/alveolar ridge, palate, and lips/labial commissure being the sites most frequently affected. The features of oral PCM lesions are similar to those reported in previous studies from Latin America. Clinicians should be aware of the oral manifestations of PCM, with emphasis on the clinicodemographic aspects and differential diagnoses, especially considering the phenomenon of the emergence of reported cases in rural and/or urban areas of Brazil

Implications on Inelastic Dark Matter from 100 Live Days of XENON100 Data

The XENON100 experiment has recently completed a dark matter run with 100.9 live-days of data, taken from January to June 2010. Events in a 48kg fiducial volume in the energy range between 8.4 and 44.6 keVnr have been analyzed. A total of three events have been found in the predefined signal region, compatible with the background prediction of (1.8 \pm 0.6) events. Based on this analysis we present limits on the WIMP-nucleon cross section for inelastic dark matter. With the present data we are able to rule out the explanation for the observed DAMA/LIBRA modulation as being due to inelastic dark matter scattering off iodine at a 90% confidence level.Comment: 3 pages, 3 figure

Digitalization of musculoskeletal risk assessment in a robotic-assisted assembly workstation

The ergonomic assessment of adopted working postures is essential for avoiding musculoskeletal risk factors in manufacturing contexts. Several observational methods based on external analyst observations are available; however, they are relatively subjective and suffer low repeatability. Over the past decade, the digitalization of this assessment has received high research interest. Robotic applications have the potential to lighten workers’ workload and improve working conditions. Therefore, this work presents a musculoskeletal risk assessment before and after robotic implementation in an assembly workstation. We also emphasize the importance of using novel and non-intrusive technologies for musculoskeletal risk assessment. A kinematic study was conducted using inertial motion units (IMU) in a convenience sample of two workers during their normal performance of assembly work cycles. The musculoskeletal risk was estimated according to a semi-automated solution, called the Rapid Upper Limb Assessment (RULA) report. Based on previous musculoskeletal problems reported by the company, the assessment centered on the kinematic analysis of functional wrist movements (flexion/extension, ulnar/radial deviation, and pronation/supination). The results of the RULA report showed a reduction in musculoskeletal risk using robotic-assisted assembly. Regarding the kinematic analysis of the wrist during robotic-assisted tasks, a significant posture improvement of 20–45% was registered (considering the angular deviations relative to the neutral wrist position). The results obtained by direct measurements simultaneously reflect the workload and individual characteristics. The current study highlights the importance of an in-field instrumented assessment of musculoskeletal risk and the limitations of the system applied (e.g., unsuitable for tracking the motion of small joints, such as the fingers).This work was supported by NORTE-06-3559-FSE-000018, integrated in the invitation NORTE-59-2018-41, aiming the Hiring of Highly Qualified Human Resources, co-financed by the Regional Operational Programme of the North 2020, thematic area of Competitiveness and Employment, through the European Social Fund (ESF). This work was also supported by FCT–Fundação para a Ciência e Tecnologia within the R&D Units Project Scope: UIDB/00319/2020