916 resultados para Non-human personhood


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Skin exposures to chemicals may lead, through percutaneous permeation, to a significant increase in systemic circulation. Skin is the primary route of entry during some occupational activities, especially in agriculture. To reduce skin exposures, the use of personal protective equipment (PPE) is recommended. PPE efficiency is characterized as the time until products permeate through material (lag time, Tlag). Both skin and PPE permeations are assessed using similar in vitro methods; the diffusion cell system. Flow-through diffusion cells were used in this study to assess the permeation of two herbicides, bentazon and isoproturon, as well as four related commercial formulations (Basagran(®), Basamais(®), Arelon(®) and Matara(®)). Permeation was measured through fresh excised human skin, protective clothing suits (suits) (Microchem(®) 3000, AgriSafe Pro(®), Proshield(®) and Microgard(®) 2000 Plus Green), and a combination of skin and suits. Both herbicides, tested by itself or as an active ingredient in formulations, permeated readily through human skin and tested suits (Tlag < 2 h). High permeation coefficients were obtained regardless of formulations or tested membranes, except for Microchem(®) 3000. Short Tlag, were observed even when skin was covered with suits, except for Microchem(®) 3000. Kp values tended to decrease when suits covered the skin (except when Arelon(®) was applied to skin covered with AgriSafe Pro and Microgard(®) 2000), suggesting that Tlag alone is insufficient in characterizing suits. To better estimate human skin permeations, in vitro experiments should not only use human skin but also consider the intended use of the suit, i.e., the active ingredient concentrations and type of formulations, which significantly affect skin permeation.

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T-cells specific for foreign (e.g., viral) antigens can give rise to strong protective immune responses, whereas self/tumor antigen-specific T-cells are thought to be less powerful. However, synthetic T-cell vaccines composed of Melan-A/MART-1 peptide, CpG and IFA can induce high frequencies of tumor-specific CD8 T-cells in PBMC of melanoma patients. Here we analyzed the functionality of these T-cells directly ex vivo, by multiparameter flow cytometry. The production of multiple cytokines (IFNγ, TNFα, IL-2) and upregulation of LAMP-1 (CD107a) by tumor (Melan-A/MART-1) specific T-cells was comparable to virus (EBV-BMLF1) specific CD8 T-cells. Furthermore, phosphorylation of STAT1, STAT5 and ERK1/2, and expression of CD3 zeta chain were similar in tumor- and virus-specific T-cells, demonstrating functional signaling pathways. Interestingly, high frequencies of functionally competent T-cells were induced irrespective of patient's age or gender. Finally, CD8 T-cell function correlated with disease-free survival. However, this result is preliminary since the study was a Phase I clinical trial. We conclude that human tumor-specific CD8 T-cells can reach functional competence in vivo, encouraging further development and Phase III trials assessing the clinical efficacy of robust vaccination strategies.

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Studies assessing skin irritation to chemicals have traditionally used laboratory animals; however, such methods are questionable regarding their relevance for humans. New in vitro methods have been validated, such as the reconstructed human epidermis (RHE) model (Episkin®, Epiderm®). The comparison (accuracy) with in vivo results such as the 4-h human patch test (HPT) is 76% at best (Epiderm®). There is a need to develop an in vitro method that better simulates the anatomo-pathological changes encountered in vivo. To develop an in vitro method to determine skin irritation using human viable skin through histopathology, and compare the results of 4 tested substances to the main in vitro methods and in vivo animal method (Draize test). Human skin removed during surgery was dermatomed and mounted on an in vitro flow-through diffusion cell system. Ten chemicals with known non-irritant (heptylbutyrate, hexylsalicylate, butylmethacrylate, isoproturon, bentazon, DEHP and methylisothiazolinone (MI)) and irritant properties (folpet, 1-bromohexane and methylchloroisothiazolinone (MCI/MI)), a negative control (sodiumchloride) and a positive control (sodiumlaurylsulphate) were applied. The skin was exposed at least for 4h. Histopathology was performed to investigate irritation signs (spongiosis, necrosis, vacuolization). We obtained 100% accuracy with the HPT model; 75% with the RHE models and 50% with the Draize test for 4 tested substances. The coefficients of variation (CV) between our three test batches were <0.1, showing good reproducibility. Furthermore, we reported objectively histopathological irritation signs (irritation scale): strong (folpet), significant (1-bromohexane), slight (MCI/MI at 750/250ppm) and none (isoproturon, bentazon, DEHP and MI). This new in vitro test method presented effective results for the tested chemicals. It should be further validated using a greater number of substances; and tested in different laboratories in order to suitably evaluate reproducibility.

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Cellular directional migration in an electric field (galvanotaxis) is one of the mechanisms guiding cell movement in embryogenesis and in skin epidermal repair. The epithelial sodium channel (ENaC), in addition to its function of regulating sodium transport in kidney, has recently been found to modulate cell locomotory speed. Here we tested whether ENaC has an additional function of mediating the directional migration of galvanotaxis in keratinocytes. Genetic depletion of ENaC completely blocks only galvanotaxis and does not decrease migration speed. Overexpression of ENaC is sufficient to drive galvanotaxis in otherwise unresponsive cells. Pharmacologic blockade or maintenance of the open state of ENaC also decreases or increases, respectively, galvanotaxis, suggesting that the channel open state is responsible for the response. Stable lamellipodial extensions formed at the cathodal sides of wild-type cells at the start of galvanotaxis; these were absent in the ENaC knockout keratinocytes, suggesting that ENaC mediates galvanotaxis by generating stable lamellipodia that steer cell migration. We provide evidence that ENaC is required for directional migration of keratinocytes in an electric field, supporting a role for ENaC in skin wound healing.

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Severe heart failure and cerebral stroke are broadly associated with the impairment of muscular function that conventional treatments struggle to restore. New technologies enable the construction of "smart" materials that could be of great help in treating diseases where the main problem is muscle weakness. These materials "behave" similarly to biological systems, because the material directly converts energy, for example electrical energy into movement. The extension and contraction occur silently like in natural muscles. The real challenge is to transfer this amazing technology into devices that restore or replace the mechanical function of failing muscle. Cardiac assist devices based on artificial muscle technology could envelope a weak heart and temporarily improve its systolic function, or, if placed on top of the atrium, restore the atrial kick in chronic atrial fibrillation. Artificial sphincters could be used to treat urinary incontinence after prostatectomy or faecal incontinence associated with stomas. Artificial muscles can restore the ability of patients with facial paralysis due to stroke or nerve injury to blink. Smart materials could be used to construct an artificial oesophagus including peristaltic movement and lower oesophageal sphincter function to replace the diseased oesophagus thereby avoiding the need for laparotomy to mobilise stomach or intestine. In conclusion, in the near future, smart devices will integrate with the human body to fill functional gaps due to organ failure, and so create a human chimera.

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The function of antigen-specific CD8+ T cells, which may protect against both infectious and malignant diseases, can be impaired by ligation of their inhibitory receptors, which include CTL-associated protein 4 (CTLA-4) and programmed cell death 1 (PD-1). Recently, B and T lymphocyte attenuator (BTLA) was identified as a novel inhibitory receptor with structural and functional similarities to CTLA-4 and PD-1. BTLA triggering leads to decreased antimicrobial and autoimmune T cell responses in mice, but its functions in humans are largely unknown. Here we have demonstrated that as human viral antigen-specific CD8+ T cells differentiated from naive to effector cells, their surface expression of BTLA was gradually downregulated. In marked contrast, human melanoma tumor antigen-specific effector CD8+ T cells persistently expressed high levels of BTLA in vivo and remained susceptible to functional inhibition by its ligand herpes virus entry mediator (HVEM). Such persistence of BTLA expression was also found in tumor antigen-specific CD8+ T cells from melanoma patients with spontaneous antitumor immune responses and after conventional peptide vaccination. Remarkably, addition of CpG oligodeoxynucleotides to the vaccine formulation led to progressive downregulation of BTLA in vivo and consequent resistance to BTLA-HVEM-mediated inhibition. Thus, BTLA activation inhibits the function of human CD8+ cancer-specific T cells, and appropriate immunotherapy may partially overcome this inhibition.

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Cross-talk between NK cells and dendritic cells (DCs) is critical for the potent therapeutic response to dsRNA, but the receptors involved remained controversial. We show in this paper that two dsRNAs, polyadenylic-polyuridylic acid and polyinosinic-polycytidylic acid [poly(I:C)], similarly engaged human TLR3, whereas only poly(I:C) triggered human RIG-I and MDA5. Both dsRNA enhanced NK cell activation within PBMCs but only poly(I:C) induced IFN-gamma. Although myeloid DCs (mDCs) were required for NK cell activation, induction of cytolytic potential and IFN-gamma production did not require contact with mDCs but was dependent on type I IFN and IL-12, respectively. Poly(I:C) but not polyadenylic-polyuridylic acid synergized with mDC-derived IL-12 for IFN-gamma production by acting directly on NK cells. Finally, the requirement of both TLR3 and Rig-like receptor (RLR) on mDCs and RLRs but not TLR3 on NK cells for IFN-gamma production was demonstrated using TLR3- and Cardif-deficient mice and human RIG-I-specific activator. Thus, we report the requirement of cotriggering TLR3 and RLR on mDCs and RLRs on NK cells for a pathogen product to induce potent innate cell activation.

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The ability of a population to adapt to changing environments depends critically on the amount and kind of genetic variability it possesses. Mutations are an important source of new genetic variability and may lead to new adaptations, especially if the population size is large. Mutation rates are extremely variable between and within species, and males usually have higher mutation rates as a result of elevated rates of male germ cell division. This male bias affects the overall mutation rate. We examined the factors that influence male mutation bias, and focused on the effects of classical life-history parameters, such as the average age at reproduction and elevated rates of sperm production in response to sexual selection and sperm competition. We argue that human-induced changes in age at reproduction or in sexual selection will affect male mutation biases and hence overall mutation rates. Depending on the effective population size, these changes are likely to influence the long-term persistence of a population.

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Chronic intake of non steroidal anti-inflammatory drugs (NSAIDs) is associated with a reduced risk of developing gastrointestinal tumors, in particular colon cancer. Increasing evidence indicates that NSAID exert tumor-suppressive activity on pre-malignant lesions (polyps) in humans and on established experimental tumors in mice. Some of the tumor-suppressive effects of NSAIDs depend on the inhibition of cyclooxygenase-2 (COX-2), a key enzyme in the synthesis of prostaglandins and thromboxane, which is highly expressed in inflammation and cancer. Recent findings indicate that NSAIDs exert their anti-tumor effects by suppressing tumor angiogenesis. The availability of COX-2-specific NSAIDs opens the possibility of using this drug class as anti-angiogenic agents in combination with chemotheapy or radiotherapy for the treatment of human cancer. Here we will briefly review recent advances in the understanding of the mechanism by which NSAIDs suppress tumor angiogenesis and discuss their potential clinical application as anti-cancer agents.

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TWEAK (TNF homologue with weak apoptosis-inducing activity) and Fn14 (fibroblast growth factor-inducible protein 14) are members of the tumor necrosis factor (TNF) ligand and receptor super-families. Having observed that Xenopus Fn14 cross-reacts with human TWEAK, despite its relatively low sequence homology to human Fn14, we examined the conservation in tertiary fold and binding interfaces between the two species. Our results, combining NMR solution structure determination, binding assays, extensive site-directed mutagenesis and molecular modeling, reveal that, in addition to the known and previously characterized β-hairpin motif, the helix-loop-helix motif makes an essential contribution to the receptor/ligand binding interface. We further discuss the insight provided by the structural analyses regarding how the cysteine-rich domains of the TNF receptor super-family may have evolved over time. DATABASE: Structural data are available in the Protein Data Bank/BioMagResBank databases under the accession codes 2KMZ, 2KN0 and 2KN1 and 17237, 17247 and 17252. STRUCTURED DIGITAL ABSTRACT: TWEAK binds to hFn14 by surface plasmon resonance (View interaction) xeFn14 binds to TWEAK by enzyme linked immunosorbent assay (View interaction) TWEAK binds to xeFn14 by surface plasmon resonance (View interaction) hFn14 binds to TWEAK by enzyme linked immunosorbent assay (View interaction).

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Large numbers and functionally competent T cells are required to protect from diseases for which antibody-based vaccines have consistently failed (1), which is the case for many chronic viral infections and solid tumors. Therefore, therapeutic vaccines aim at the induction of strong antigen-specific T-cell responses. Novel adjuvants have considerably improved the capacity of synthetic vaccines to activate T cells, but more research is necessary to identify optimal compositions of potent vaccine formulations. Consequently, there is a great need to develop accurate methods for the efficient identification of antigen-specific T cells and the assessment of their functional characteristics directly ex vivo. In this regard, hundreds of clinical vaccination trials have been implemented during the last 15 years, and monitoring techniques become more and more standardized.

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BACKGROUND: Tuberculosis remains one of the world's deadliest transmissible diseases despite widespread use of the BCG vaccine. MTBVAC is a new live tuberculosis vaccine based on genetically attenuated Mycobacterium tuberculosis that expresses most antigens present in human isolates of M tuberculosis. We aimed to compare the safety of MTBVAC with BCG in healthy adult volunteers. METHODS: We did this single-centre, randomised, double-blind, controlled phase 1 study at the Centre Hospitalier Universitaire Vaudois (CHUV; Lausanne, Switzerland). Volunteers were eligible for inclusion if they were aged 18-45 years, clinically healthy, HIV-negative and tuberculosis-negative, and had no history of active tuberculosis, chemoprophylaxis for tuberculosis, or BCG vaccination. Volunteers fulfilling the inclusion criteria were randomly assigned to three cohorts in a dose-escalation manner. Randomisation was done centrally by the CHUV Pharmacy and treatments were masked from the study team and volunteers. As participants were recruited within each cohort, they were randomly assigned 3:1 to receive MTBVAC or BCG. Of the participants allocated MTBVAC, those in the first cohort received 5 × 10(3) colony forming units (CFU) MTBVAC, those in the second cohort received 5 × 10(4) CFU MTBVAC, and those in the third cohort received 5 × 10(5) CFU MTBVAC. In all cohorts, participants assigned to receive BCG were given 5 × 10(5) CFU BCG. Each participant received a single intradermal injection of their assigned vaccine in 0·1 mL sterile water in their non-dominant arm. The primary outcome was safety in all vaccinated participants. Secondary outcomes included whole blood cell-mediated immune response to live MTBVAC and BCG, and interferon γ release assays (IGRA) of peripheral blood mononuclear cells. This trial is registered with ClinicalTrials.gov, number NCT02013245. FINDINGS: Between Jan 23, 2013, and Nov 6, 2013, we enrolled 36 volunteers into three cohorts, each of which consisted of nine participants who received MTBVAC and three who received BCG. 34 volunteers completed the trial. The safety of vaccination with MTBVAC at all doses was similar to that of BCG, and vaccination did not induce any serious adverse events. All individuals were IGRA negative at the end of follow-up (day 210). After whole blood stimulation with live MTBVAC or BCG, MTBVAC was at least as immunogenic as BCG. At the same dose as BCG (5×10(5) CFU), although no statistical significance could be achieved, there were more responders in the MTBVAC group than in the BCG group, with a greater frequency of polyfunctional CD4+ central memory T cells. INTERPRETATION: To our knowledge, MTBVAC is the first live-attenuated M tuberculosis vaccine to reach clinical assessment, showing similar safety to BCG. MTBVAC seemed to be at least as immunogenic as BCG, but the study was not powered to investigate this outcome. Further plans to use more immunogenicity endpoints in a larger number of volunteers (adults and adolescents) are underway, with the aim to thoroughly characterise and potentially distinguish immunogenicity between MTBVAC and BCG in tuberculosis-endemic countries. Combined with an excellent safety profile, these data support advanced clinical development in high-burden tuberculosis endemic countries. FUNDING: Biofabri and Bill & Melinda Gates Foundation through the TuBerculosis Vaccine Initiative (TBVI).

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This study examined students considered at risk of non-completion of their Ontario Secondary School Diploma and aimed to offer insight into the questions, "What factors currently lead to school disconnect" and "How can these factors be addressed?" Eight students currently enrolled in an alternative learning environment participated in the study. Each was asked to take part in two, digitally recorded interviews that were subsequently transcribed by the researcher. The data were then coded and analysed according to specific themes: obstacles, empowerment, goals, views about success, opinions of school, and power of the teacher. From these themes, three broad focus areas emerged that were used to keep the data analysis focused: worldview, school effects, and self-image. Variances between the data collected and ideas presented in the current literature were highlighted as a reminder that when dealing with a human population, we cannot rely on textbook definitions and theory alone.

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Temple Grandin was born in Boston, Massachusetts on August 29,1947 to Richard Grandin and Eustacia Cutler. She was diagnosed with autism at age 2. She suffered from delayed speech development and did not begin to speak until the age of 4. Temple’s mother defied the doctors and kept her out of institutions. Temple was given speech therapy as well as an intensive education. Her high school science teacher and her aunt on a ranch in Arizona inspired Temple to continue her studies and pursue a career as a scientist and livestock equipment designer.She graduated from Hampshire Country School (a boarding school for gifted children) in Ridge, New Hampshire in 1966, and earned a bachelor’s degree in psychology from Franklin Pierce College in 1970. In 1975, she received a master’s degree in animal science from Arizona State University and then a doctoral degree in animal science from the University of Illinois in 1989. She is currently a professor at Colorado State University. Dr. Grandin is one of the world’s leaders in the design of livestock handling facilities. She has done extensive work in design of handling facilities for animals and has developed animal welfare guidelines for the meat industries. Dr. Grandin is a past member of the board of directors of the Autism Society of America. She lectures to parents and teachers throughout the U.S. on her experiences with autism. She makes the case that the world needs people on the autism spectrum: visual thinkers, pattern thinkers and verbal thinkers. Some of Temple Grandin’s books include: Animals Make Us Human, Animals in Translation, The Way I See It, The Autistic Brain, and Different…Not Less. In 2010, a movie entitled “Temple Grandin” starring Clare Danes was released. The movie was based on Grandin’s own writings. Temple Grandin is an expert on animal behavior, a bestselling author, and an autism activist. In 2010, she was listed in the “Heroes” category in the “Time” list of the world’s 100 most influential people. She has received numerous awards including an honorary doctorate from McGill, the University of Illinois and Duke University. Temple Granin is a philosophical leader of both the animal welfare and autism advocacy movements. sources: http://www.templegrandin.com/ http://en.wikipedia.org/wiki/Temple_Grandin

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Most human genes undergo alternative splicing and loss of splicing fidelity is associated with disease. Epigenetic silencing of hMLH 1 via promoter cytosine methylation is causally linked to a subset of sporadic non-polyposis colon cancer and is reversible by 5-aza-2' -deoxycytidine treatment. Here I investigated changes in hMLHI mRNA splicing profiles in normal fibroblasts and colon cancer-derived human cell lines. I established the types and frequencies of hMLHI mRNA transcripts generated under baseline conditions, after hydrogen peroxide induced oxidative stress, and in acutely 5-aza-2' -deoxycytidine-treated and stably derepressed cancer cell lines. I found that hMLHI is extensively spliced under all conditions including baseline (50% splice variants), the splice variant distribution changes in response to oxidative stress, and certain splice variants are sensitive to 5- aza-2' -deoxycytidine treatment: Splice variant diversity and frequency of exon 17 skipping correlates with the level of hMLHI promoter methylation suggesting a link between promoter methylation and mRNA splicing.