Gastrointestinal Helminths of Two Species of Mouse Opossums (\u3ci\u3eMarmosa demerarae\u3c/i\u3e and \u3ci\u3eMarmosa murina\u3c/i\u3e) from French Guiana

The woolly mouse opossum Marmosa demerarae and the murine opossum, Marmosa murina, occur in sympatry across most of their range; however, they are not syntopic in that M. demerarae is more abundant in the canopy of primary and secondary forest, while M. murina is scansorial and appears to be more abundant in lower forest strata. We herein present a survey and comparison of the helminths occurring in these 2 species in French Guiana based on examinations of 18 individuals of M. murina and 21 individuals of M. demerarae. At the level of the component community, species richness was established at 12 for M. demerarae and 14 for M. murina; the nematodes Pterygodermatites (Paucipectines) elegans and Aspidodera raillieti were established as the most abundant and prevalent species in M. demerarae and M. murina, respectively. Infracommunities in both species had an average species richness of 3.7 and 3.8, respectively. Both species share 12 species of parasites, yet Phaneropsolus philanderi, Pterygodermatites (Paucipectines) elegans, Travassostrongylus paraquintus, Trichuris reesali, and Spirura trinitatis were significantly more frequent in M. demerarae. Infections also included Mathevotaenia bivittata, an unidentified anoplocephalid, and Viannaia venezuelensis, all 3 species of which were more frequent in M. murina

A disilene base adduct with a dative Si–Si single bond.

An experimental and theoretical study of the base- stabilized disilene 1 is reported, whichforms at lowtemper- atures in the disproportionation reaction of Si 2 Cl 6 or neo- Si 5 Cl 12 with equimolar amounts of NMe 2 Et. Single-crystal X- ray diffraction and quantum-chemical bonding analysis dis- close an unprecedented structure in silicon chemistry featuring adative Si!Si single bond between two silylene moieties, Me 2 EtN!SiCl 2 !Si(SiCl 3 ) 2 .The central ambiphilic SiCl 2 group is linked by dative bonds to the amine donor and the bis(trichlorosilyl)silylene acceptor,which leads to push–pull stabilization. Based on experimental and theoretical examina- tions aformation mechanism is presented that involves an autocatalytic reaction of the intermediately formed anion Si(SiCl 3 ) 3 ¢ with neo-Si 5 Cl 12 to yield 1

Avaliação da cobertura vacinal do esquema básico para o primeiro ano de vida

Immunization coverage was evaluated in all 12-23 month-old children living in the area were five years before a Primary Care Practice had been set up. All children were investigated through home visits, checking of the immunization chart and relying on mothers' information. In 1986, a baseline study had identified an immunization coverage of under 60% for each of the scheduled vaccines. The current study confirmed that coverage was of 87% for three doses of DTP, 89% for Sabin, 88% for one dose of measles vaccine and 79% for BCG. Despite the high coverage achieved for each specific vaccine, when the basic schedule for the first year was verified, it was observed that only 75% of the children had received the full scheme. Immunization coverage is uneven in different census tracts, being higher in the poorest and more remot areas, where seam the health has given extra attention. A comparison with the routine administrative evaluation of the immunization coverage showed that this underestimated the real coverage. Maternal immunization uptake was also evaluated (antitetanus vaccine during pregnancy) and only 49% of the women were found to be adequately protected. The information collected led to a reorganization of the whole immunization program in a 100% coverage.Em 1991 avaliou-se a cobertura vacinal em crianças de 12 a 23 meses de idade no território de responsabilidade de um Posto de Atenção Primária à Saúde, na periferia da Zona Norte de Porto Alegre, RS, Brasil, cinco anos após sua implantação, com a finalidade de melhorar a qualidade das ações de saúde desenvolvidas no serviço. Foram investigadas todas as crianças através de um inquérito domiciliar, observando-se a carteira de vacinas e as informações da mãe. Em 1986, um inquérito inicial havia identificado uma cobertura vacinal inferior a 60% para cada uma das vacinas. A atual cobertura vacinal (doses comprovadas) para três doses da vacina DPT (Difteria, Pertussis e Tétano), três doses da Sabin (antipoliomielite), uma dose da anti-sarampo (VAS) e uma dose de BCG são, respectivamente 87, 89, 88 e 79%. Apesar das altas coberturas observadas por tipos de vacinas, quando se verificou para cada criança se o esquema básico do primeiro ano de vida estava completo (3 doses de DPT + 3 doses de Sabin + 1 dose de VAS + 1 dose de BCG), encontrou-se apenas 75% das crianças na citada situação. A cobertura vacinal é heterogênea dentro do território, sendo maior naquelas áreas caracterizadas por piores condições socioeconômicas, onde a equipe de saúde havia intensificado esforços. A comparação com o método administrativo de avaliação de cobertura, realizado mensalmente, mostrou a não-adequação desse, que subestimava a cobertura vacinal. Avaliou-se a situação vacinal das mães, para vacina antitetânica, e apenas 49% das crianças estavam protegidas contra o tétano neonatal. Os dados obtidos subsidiaram a imediata reestruturação das ações do programa, com vistas a atingir uma cobertura vacinal de 100%, e melhorar a qualidade das ações de saúde prestadas pela equipe

Forced Moves or Good Tricks in Design Space? Landmarks in the Evolution of Neural Mechanisms for Action Selection

This review considers some important landmarks in animal evolution, asking to what extent specialized action-selection mechanisms play a role in the functional architecture of different nervous system plans, and looking for “forced moves” or “good tricks” (see Dennett, D., 1995, Darwin’s Dangerous Idea, Penguin Books, London) that could possibly transfer to the design of robot control systems. A key conclusion is that while cnidarians (e.g. jellyfish) appear to have discovered some good tricks for the design of behavior-based control systems—largely lacking specialized selection mechanisms—the emergence of bilaterians may have forced the evolution of a central ganglion, or “archaic brain”, whose main function is to resolve conflicts between peripheral systems. Whilst vertebrates have many interesting selection substrates it is likely that here too the evolution of centralized structures such as the medial reticular formation and the basal ganglia may have been a forced move because of the need to limit connection costs as brains increased in size

Prediction of peptide and protein propensity for amyloid formation

Understanding which peptides and proteins have the potential to undergo amyloid formation and what driving forces are responsible for amyloid-like fiber formation and stabilization remains limited. This is mainly because proteins that can undergo structural changes, which lead to amyloid formation, are quite diverse and share no obvious sequence or structural homology, despite the structural similarity found in the fibrils. To address these issues, a novel approach based on recursive feature selection and feed-forward neural networks was undertaken to identify key features highly correlated with the self-assembly problem. This approach allowed the identification of seven physicochemical and biochemical properties of the amino acids highly associated with the self-assembly of peptides and proteins into amyloid-like fibrils (normalized frequency of β-sheet, normalized frequency of β-sheet from LG, weights for β-sheet at the window position of 1, isoelectric point, atom-based hydrophobic moment, helix termination parameter at position j+1 and ΔGº values for peptides extrapolated in 0 M urea). Moreover, these features enabled the development of a new predictor (available at http://cran.r-project.org/web/packages/appnn/index.html) capable of accurately and reliably predicting the amyloidogenic propensity from the polypeptide sequence alone with a prediction accuracy of 84.9 % against an external validation dataset of sequences with experimental in vitro, evidence of amyloid formation

Small Heat Shock Proteins Potentiate Amyloid Dissolution by Protein Disaggregases from Yeast and Humans

The authors define how small heat-shock proteins synergize to regulate the assembly and disassembly of a beneficial prion, and then they exploit this knowledge to identify the human amyloid depolymerase

There Is No Safe Dose of Prions

Understanding the circumstances under which exposure to transmissible spongiform encephalopathies (TSEs) leads to infection is important for managing risks to public health. Based upon ideas in toxicology and radiology, it is plausible that exposure to harmful agents, including TSEs, is completely safe if the dose is low enough. However, the existence of a threshold, below which infection probability is zero has never been demonstrated experimentally. Here we explore this question by combining data and mathematical models that describe scrapie infections in mice following experimental challenge over a broad range of doses. We analyse data from 4338 mice inoculated at doses ranging over ten orders of magnitude. These data are compared to results from a within-host model in which prions accumulate according to a stochastic birth-death process. Crucially, this model assumes no threshold on the dose required for infection. Our data reveal that infection is possible at the very low dose of a 1000 fold dilution of the dose that infects half the challenged animals (ID50). Furthermore, the dose response curve closely matches that predicted by the model. These findings imply that there is no safe dose of prions and that assessments of the risk from low dose exposure are right to assume a linear relationship between dose and probability of infection. We also refine two common perceptions about TSE incubation periods: that their mean values decrease linearly with logarithmic decreases in dose and that they are highly reproducible between hosts. The model and data both show that the linear decrease in incubation period holds only for doses above the ID50. Furthermore, variability in incubation periods is greater than predicted by the model, not smaller. This result poses new questions about the sources of variability in prion incubation periods. It also provides insight into the limitations of the incubation period assay

Intraosseous foreign body granuloma in rotator cuff repair with bioabsorbable suture anchor

Biodegradable implants lead to problems such as cyst formation, soft-tissue inflammation, loose implant fragments or local osteolysis. This report represents the first published case of an intraosseous foreign body granuloma in the humeral head after arthroscopic rotator cuff tear fixation with a poly-l-lactide (PLLA) suture anchor. A 48-year-old female patient presented with pain in her right shoulder. A refixation of her right supraspinatus tendon with a biodegradable suture anchor was performed 11 months ago at an external hospital. Laboratory tests showed normal values for C-reactive protein, leukocytes and the erythrocyte sedimentation rate. No signs of infection or instability were noted. The visual analogue scale (VAS) was 8, the simple shoulder test (SST) was 4 and the American shoulder and elbow surgeons score (ASES) was 44. Plain radiographs showed high lucency in the area of the tuberculum majus. MRI showed an intra- and extraosseous mass surrounded by fluid in this area. Surgical care involved arthroscopic debridement and removal of the suture anchor. Histological examination revealed a foreign body granuloma. At the 18-month follow-up the patient was nearly pain-free. The VAS was 2, SST was 10 and ASES was 88. Foreign body granulomas are a well known but rarely described complication that arises after the use of biodegradable suture anchors in shoulder surgery. Every patient presenting with shoulder pain after usage of a biodegradable fixation material should be evaluated closely. Orthopaedic surgeons should be aware of the possibility of delayed foreign body reactions, especially after using PLLA anchors

Comparative evaluation of the tendon-bone interface contact pressure in different single- versus double-row suture anchor repair techniques

The aim of the study was to evaluate the time zero contact pressure over a defined rotator cuff footprint using different repair and stitch techniques in an established sheep model. Forty fresh-frozen sheep shoulders were randomly assigned to five repair groups: single-row repair using simple stitches (SRA-s), single-row repair using horizontal mattress stitches (SRA-m), and single-row repair using arthroscopic Mason-Allen stitches (SRA-ama). Double-row repair was either performed with a combination of simple and horizontal mattress stitches (DRA-sm) or with arthroscopic Mason-Allen/horizontal mattress stitches (DRA-amam). Investigations were performed using a pressure-sensitive film system. The average contact pressure and pressure pattern were measured for each group. Contact pressure was lowest in SRA-m followed by SRA-s. SRA-ama showed highest contact pressure of all single-row treatment groups (P < 0.05). DRA-amam presented the highest overall contact pressure (P < 0.05), whereas DRA-sm exerted contact pressure equal to that of SRA-ama. Both double-row techniques showed the most expanded pressure pattern. Average contact pressures for the more complex single- and double-row techniques utilizing arthroscopic Mason-Allen stitches were greater than were those of the repair techniques utilizing simple and horizontal mattress stitches. However, the contact pattern between the anchors could be increased by using the double-row technique, resulting in more footprint coverage compared to patterns utilizing the single-row techniques. These results support the use of the more complex arthroscopic Mason-Allen stitches and may improve the environment for healing of the repaired rotator cuff tendon