Several Nuclear Events during Apoptosis Depend on Caspase-3 Activation but Do Not Constitute a Common Pathway

A number of nuclear events occur during apoptosis, including DNA laddering, nuclear lamina breakdown, phosphorylation of histones H2B and histone H2AX, and the tight binding to chromatin of HMGB1 and CAD, the nuclease responsible for DNA laddering. We have performed an epistasis analysis to investigate whether these events cluster together in pathways. We find that all depend directly or indirectly on caspase-3 activation. CAD activation, H2AX phosphorylation and DNA laddering cluster together into a pathway, but all other events appear to be independent of each other downstream of caspase-3, and likely evolved subject to different functional pressures

Los otros ciudadanos: Asociacionismo, prensa y política de los negros montevideanos a fines del siglo XIX

El artículo trata sobre cómo algunos grupos de la población afrodescendiente se organizaron y entablaron diferentes acciones políticas en la ciudad de Montevideo durante el año electoral de 1872. La paz, acordada en abril de ese año, que puso fin a la conocida como Revolución de las Lanzas, auspició —al menos entre algunos grupos de intelectuales— un cambio en la forma de pensar y dirimir las diferencias políticas. Dos organizaciones de negros montevideanos jugaron un rol protagónico en este contexto: el Club Igualdad y el Club Defensa. Ambos mostraron -a través de sus presencias en la prensa escrita montevideana- la tensión que existía en ese momento histórico entre tradición y modernidad en los proyectos de construcción de la ciudadanía

DR.SGX: Hardening SGX Enclaves against Cache Attacks with Data Location Randomization

Recent research has demonstrated that Intel's SGX is vulnerable to various software-based side-channel attacks. In particular, attacks that monitor CPU caches shared between the victim enclave and untrusted software enable accurate leakage of secret enclave data. Known defenses assume developer assistance, require hardware changes, impose high overhead, or prevent only some of the known attacks. In this paper we propose data location randomization as a novel defensive approach to address the threat of side-channel attacks. Our main goal is to break the link between the cache observations by the privileged adversary and the actual data accesses by the victim. We design and implement a compiler-based tool called DR.SGX that instruments enclave code such that data locations are permuted at the granularity of cache lines. We realize the permutation with the CPU's cryptographic hardware-acceleration units providing secure randomization. To prevent correlation of repeated memory accesses we continuously re-randomize all enclave data during execution. Our solution effectively protects many (but not all) enclaves from cache attacks and provides a complementary enclave hardening technique that is especially useful against unpredictable information leakage

Nutrient sensing and acquisition in fungi: Mechanisms promoting pathogenesis in plant and human hosts

Fungal pathogens destroy our crops and cause hazardous human infections, therefore threatening our health and food security. The ability of fungal pathogens to sense and respond to dynamic host microenvironments enables the establishment and progression of disease. Sensing nutritional cues is vital throughout fungal infection of either plants or mammals: enabling the pathogen to invade, adapt and survive in the face of host immunity. Acquiring nutrients from their host for energy, growth and repair is also essential to a fungal pathogen's success. Cell-surface proteins embedded in the fungal plasma membrane sense and transport host macro- and micronutrients, including carbon and nitrogen sources and minerals such as iron and zinc. Using examples from model crop (Fusarium graminearum, Magnaporthe oryzae and Ustilago maydis) and human (Aspergillus fumigatus, Candida albicans, Cryptococcus neoformans) pathogens we review the nutrient sensing and transporting roles of fungal cell-surface receptor, transporter and transceptor proteins, and their importance to plant and human fungal disease. We discuss how their cellular localisation, central role in cell signalling and importance to disease makes these fungal cell-surface proteins candidates in the search for new strategies to control fungal diseases, while highlighting the areas where further research is needed to make this possible.</p

Nutrient sensing and acquisition in fungi: Mechanisms promoting pathogenesis in plant and human hosts

Fungal pathogens destroy our crops and cause hazardous human infections, therefore threatening our health and food security. The ability of fungal pathogens to sense and respond to dynamic host microenvironments enables the establishment and progression of disease. Sensing nutritional cues is vital throughout fungal infection of either plants or mammals: enabling the pathogen to invade, adapt and survive in the face of host immunity. Acquiring nutrients from their host for energy, growth and repair is also essential to a fungal pathogen's success. Cell-surface proteins embedded in the fungal plasma membrane sense and transport host macro- and micronutrients, including carbon and nitrogen sources and minerals such as iron and zinc. Using examples from model crop (Fusarium graminearum, Magnaporthe oryzae and Ustilago maydis) and human (Aspergillus fumigatus, Candida albicans, Cryptococcus neoformans) pathogens we review the nutrient sensing and transporting roles of fungal cell-surface receptor, transporter and transceptor proteins, and their importance to plant and human fungal disease. We discuss how their cellular localisation, central role in cell signalling and importance to disease makes these fungal cell-surface proteins candidates in the search for new strategies to control fungal diseases, while highlighting the areas where further research is needed to make this possible.</p

RNAseq reveals hydrophobins that are involved in the adaptation of aspergillus nidulans to lignocellulose

Background Sugarcane is one of the world’s most profitable crops. Waste steam-exploded sugarcane bagasse (SEB) is a cheap, abundant, and renewable lignocellulosic feedstock for the next-generation biofuels. In nature, fungi seldom exist as planktonic cells, similar to those found in the nutrient-rich environment created within an industrial fermenter. Instead, fungi predominantly form biofilms that allow them to thrive in hostile environments. Results In turn, we adopted an RNA-sequencing approach to interrogate how the model fungus, Aspergillus nidulans, adapts to SEB, revealing the induction of carbon starvation responses and the lignocellulolytic machinery, in addition to morphological adaptations. Genetic analyses showed the importance of hydrophobins for growth on SEB. The major hydrophobin, RodA, was retained within the fungal biofilm on SEB fibres. The StuA transcription factor that regulates fungal morphology was up-regulated during growth on SEB and controlled hydrophobin gene induction. The absence of the RodA or DewC hydrophobins reduced biofilm formation. The loss of a RodA or a functional StuA reduced the retention of the hydrolytic enzymes within the vicinity of the fungus. Hence, hydrophobins promote biofilm formation on SEB, and may enhance lignocellulose utilisation via promoting a compact substrate-enzyme-fungus structure. Conclusion This novel study highlights the importance of hydrophobins to the formation of biofilms and the efficient deconstruction of lignocellulose

Intra-arterial adenoviral mediated tumor transfection in a novel model of cancer gene therapy

BACKGROUND: The aim of the present study was to develop and characterize a novel in vivo cancer gene therapy model in which intra-arterial adenoviral gene delivery can be characterized. In this model, the rat cremaster muscle serves as the site for tumor growth and provides convenient and isolated access to the tumor parenchyma with discrete control of arterial and venous access for delivery of agents. RESULTS: Utilizing adenovirus encoding the green fluorescent protein we demonstrated broad tumor transfection. We also observed a dose dependant increment in luciferase activity at the tumor site using an adenovirus encoding the luciferase reporter gene. Finally, we tested the intra-arterial adenovirus dwelling time required to achieve optimal tumor transfection and observed a minimum time of 30 minutes. CONCLUSION: We conclude that adenovirus mediated tumor transfection grown in the cremaster muscle of athymic nude rats via an intra-arterial route could be achieved. This model allows definition of the variables that affect intra-arterial tumor transfection. This particular study suggests that allowing a defined intra-tumor dwelling time by controlling the blood flow of the affected organ during vector infusion can optimize intra-arterial adenoviral delivery

Molecular biology of the dimorphic fungi Paracoccidioides SPP

Paracoccidioides spp, herein commonly referred as Paracoccidioides brasiliensis, is the etiological agent of racoccidioidomycosis (PCM), the most prevalent systemic mycosis endemic in Latin America. Many aspects of the biology of P. brasiliensis remain unknown, in particular its ecology and the apparent lack of a sexual reproduction stage in its life cycle. This review will highlight the current knowledge on the genetics and genomics of P. brasiliensis, its most important putative virulence factors and the challenges for developing genetic tools in this organism. P. brasiliensis is a dimorphic ascomycete fungus belonging to the order Onygenales, family Ajellomycetaceae. The P. brasiliensis pathogenic yeast form is haracterized by a multiple-budding and multinucleate nature, with a highly polymorphic cellular shape. Successful infection and dissemination by P. brasiliensis requires initial interaction of the fungus with host cells. The fungus has to adhere to host cells after which internalization of the fungus takes place. Gp43 is a 43-kDa glycoprotein that participates in the interaction with the host at different levels. There are very few putative virulence factors described in P. brasiliensis,amongthem an extracellular phospholipase B, a 32-kDa haloacid dehalogenase PbHad32 that was shown to bind laminin, fibrinogen, and fibronectin, and to be important for initial adhesion to pulmonary epithelial cells, the pigment melanin, and the Rho-like GTPase PbCdc42. The morphological transition of P. brasiliensis from mycelium to the yeast form is a key process for the infectivity of the fungus. There are several transcriptional profiling studies addressing which genes have increased or decreased mRNA accumulation during mycelium-to-yeast transitions. Functional genomics studies in P. brasiliensis have been hampered by the absence of efficient molecular techniques that enable targeted gene inactivation in this fungus. However, an optimized Agrobacterium tumefaciens-mediated transformation method has been developed and was used to knock-down expression of the genes encoding the Rho-like GTPase PbCdc42 and the HAD-type hydrolase PbHad32. A challenge for the future is the development of mutagenesis methods that allow for the creation of targeted insertional gene mutants in Paracoccidioides spp. The complete genome sequencing of three isolates of Paracoccidioides species provides the opportunity to perform more complete evaluations of the transcriptomic and proteomic data, and to understand the biology and virulence of these important pathogenic fungi.Fundação para a Ciência e Tecnologia (FCT) - Bolsa nº PTDC/BIA-MIC/108309/2008Fundação de Amparo a Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento. Científico e Tecnológic

Magnetic resonance imaging urodynamics: technique development and preliminary results

OBJECTIVES: In this preliminary study we report the development of the video urodynamic technique using magnetic resonance imaging (MRI). MATERIALS AND METHODS: We studied 6 women with genuine stress urinary incontinence, diagnosed by history and physical examination. Urodynamic examination was performed on multichannel equipment with the patient in the supine position. Coughing and Valsalva maneuvers were performed at volumes of 150, 250 and 350 mL. Simultaneously, MRI was carried out by using 1.5 T GE Signa CV/i high-speed scanner with real time fluoroscopic imaging possibilities. Fluoroscopic imaging was accomplished in the corresponding planes with T2-weighted single shot fast spin echo sequences at a speed of about 1 frame per second. Both studies were recorded and synchronized, resulting in a single video urodynamic examination. RESULTS: Dynamic MRI with cine-loop reconstruction of 1 image per second demonstrated the movement of all compartment of the relaxed pelvis during straining with the concomitant registration of abdominal and intravesical pressures. In 5 patients, urinary leakage was demonstrated during straining and the Valsalva leak point pressure (VLPP) was determined as the vesical pressure at leak subtracted from baseline bladder pressure. Mean VLPP was 72.6 cm H2O (ranging from 43 to 122 cm H2O). CONCLUSIONS: The concept of MRI video urodynamics is feasible. In a clinical perspective, practical aspects represent a barrier to daily use and it should be recommended for research purposes.Federal University of São Paulo Department of UrologyUNIFESP, Department of UrologySciEL