Assignment of individual structures from intermetalloid nickel gallium cluster ensembles.

Poorly selective mixed-metal cluster synthesis and separation yield reaction solutions of inseparable intermetalloid cluster mixtures, which are often discarded. High-resolution mass spectrometry, however, can provide precise compositional data of such product mixtures. Structure assignments can be achieved by advanced computational screening and consideration of the complete structural space. Here, we experimentally verify structure and composition of a whole cluster ensemble by combining a set of spectroscopic techniques. Our study case are the very similar nickel/gallium clusters of M12, M13 and M14 core composition Ni6+xGa6+y (x + y ≤ 2). The rationalization of structure, bonding and reactivity is built upon the organometallic superatom cluster [Ni6Ga6](Cp*)6 = [Ga6](NiCp*)6 (1; Cp* = C5Me5). The structural conclusions are validated by reactivity tests using carbon monoxide, which selectively binds to Ni sites, whereas (triisopropylsilyl)acetylene selectively binds to Ga sites.

Transmission-Blocking Vaccines for Canine Visceral Leishmaniasis: New Progress and Yet New Challenges.

Dogs with visceral leishmaniasis play a key role in the transmission cycle of Leishmania infantum to humans in the urban environment. There is a consensus regarding the importance of developing a vaccine to control this disease. Despite many efforts to develop a protective vaccine against CVL, the ones currently available, Leish-tec® and LetiFend®, have limited effectiveness. This is due, in part, to the complexity of the immune response of the naturally infected dogs against the parasite and the complexity of the parasite transmission cycle. Thus, strategies, such as the development of a transmission-blocking vaccines (TBVs) already being applied to other vector-borne diseases like malaria and dengue, would be an attractive alternative to control leishmaniasis. TBVs induce the production of antibodies in the vertebrate host, which can inhibit parasite development in the vector and/or interfere with aspects of vector biology, leading to an interruption of parasite transmission. To date, there are few TBV studies for CVL and other leishmaniasis forms. However, the few studies that exist show promising results, thus justifying the further development of this approach.

CROSS-CULTURAL ADAPTATION OF THE HOSPITAL ETHICAL CLIMATE SURVEY TO BRAZIL.

Background and Purpose: Adapting cross-culturally the Hospital Ethical Climate Survey to Brazilian nurses. Methods: A methodological study comprising translation, back translation, multidisciplinary committee, expert panel, pilot test and validation of the instrument. The validation was carried out with 269 nurses of a university hospital in the South of Brazil. Results: In the validation step, the quadratic weighted Kappa test-retest and the correlation coefficient ranged from 0.15 to 0.74. All factor loadings were higher than 0.4, ranging from 0.445 to 0.859. The Portuguese version of the instrument had a 0.93 Cronbach's alpha and the confirmatory analysis demonstrated the model's suitability with five factors and 26 items validated. Conclusions: The version of the instrument adapted to Brazilian Portuguese was considered valid and reliable in this sample.

Nurses' assessment of the ethical climate of a university hospital in the South of Brazil.

Background: Ethical climate can be defined as the healthcare professionals' perceptions of the ethical treatment of healthcare issues and human interactions in their work environment. A number of studies on ethical climate are being carried out in several countries. In Brazil, however, research on the matter is still incipient, especially among hospital nurses. Aim: To assess nurses' perception of the ethical climate in a university hospital in the South of Brazil. Methods: Cross-sectional study carried out with 269 nurses from a university hospital, using a sociodemographic and occupational profiling survey and the Hospital Ethical Climate Survey - Brazilian version. Data analysis was done through descriptive statistics. Results: The nurses' perception of the ethical climate was positive (3.68 ± 0.55). Among the five assessment factors, 'peers' had the highest score (4.07 ± 0.57), whereas 'physicians' had the lowest score (3.26 ± 0.70) for ethical climate. Conclusion: In general, the ethical climate was perceived as positive, with small variations between the factors of the instrument. Ethical climate could be enhanced through strategies that encourage interpersonal relationships. This study shows the importance of a positive ethical climate based on good relationships between healthcare professionals for ensuring better care.

Consumo de tabaco y alcohol y comportamientos de salud entre estudiantes de enfermería / O consumo de tabaco e álcool e os comportamentos de saúde em estudantes de enfermagen / Tobacco and alcohol consumption and health behaviors among nursing students

Objective: To evaluate the association between attitudes, health behaviors, and the use of tobacco and alcohol among nursing students. Materials and method: Exploratory, descriptive and cross-sectional study conducted with 182 undergraduate nursing students in the countryside of São Paulo, Brazil. Sociodemographic Information Form, Alcohol Use Disorders Identification Test ­ C (AUDIT-C), Fagerström Test for Nicotine Dependence (FTND), Attitudes and Health Behaviors Questionnaire (AHBQ), and Patient Health Questionnaire ­ 2 (PHQ-2) were applied. Results: More than half of the students showed appropriate health behaviors and positive attitudes. Approximately 50% of the participants had consumed alcoholic beverages in the last month. Experimental use of illicit drugs and smoking were also observed. In addition, students who reported excessive alcohol use presented a deficit in self-care. Conclusions: The precariousness in health attitudes and behaviors identified in this study was associated with various patterns of psychoactive substance use. Thus, the results indicate the need for interventions aimed at promoting well-being and a healthy lifestyle in the university environment.

Objetivo: evaluar la asociación entre las actitudes, los comportamientos de salud y el uso de tabaco y alcohol entre un grupo de estudiantes de enfermería. Materiales y método: estudio exploratorio, descriptivo y transversal realizado con 182 estudiantes de pregrado en enfermería en São Paulo, Brasil. Se aplicaron los siguientes instrumentos: Formulario de Información Sociodemográfica, Prueba de Identificación de Trastornos Derivados del Consumo de Alcohol ­ C (AUDIT-C), Test de Fagerström para Adicción a la Nicotina (FTND), Cuestionario sobre Actitudes y Conductas de Salud (CACS) y Cuestionario de Salud del Paciente ­ 2 (PHQ-2). Resultados: más de la mitad de los estudiantes mostraron comportamientos de salud apropiados y actitudes positivas. Aproximadamente 50 % de los participantes había consumido bebidas alcohólicas en el último mes. También se observó el uso experimental de drogas ilícitas y tabaco. Además, los estudiantes que reportaron el consumo excesivo de alcohol presentaron un déficit en el autocuidado. Conclusiones: la precariedad en las actitudes y los comportamientos de salud identificados en este estudio fue asociada con diversos patrones de uso de sustancias psicoactivas. Los resultados señalan la necesidad de intervenciones destinadas a promover el bienestar y un estilo de vida saludable en el ámbito universitario.

Objetivo: avaliar a associação entre as atitudes, os comportamentos de saúde e o uso de tabaco e álcool num grupo de estudantes de enfermagen. Materiais e método: estudo exploratório, descritivo e transversal realizado com 182 estudantes de graduação em enfermagem em São Paulo, Brasil. Foram aplicados os seguintes instrumentos: Formulário de Informação Sociodemográfica, Teste de Identificação de Transtornos Derivados do Consumo de Álcool-C (AUDIT-C), Teste de Fagerström para a Dependência de Nicotina (FTND), Questionário sobre Atitudes e Condutas de Saúde (CACS) e Questionário de Saúde do Paciente-2 (PHQ-2). Resultados: mais da metade dos estudantes mostraram comportamentos de saúde apropriados e atitudes positivas. Aproximadamente 50 % dos participantes tinham consumido bebidas alcoólicas no último mês. Também foi observado o uso experimental de drogas ilícitas e tabaco. Além disso, os estudantes que relataram o consumo excessivo de álcool apresentaram um déficit no autocuidado. Conclusões: a precariedade nas atitudes e comportamentos de saúde identificados neste estudo foi associada com diversos padrões de uso de substâncias psicoativas. Os resultados indicam a necessidade de intervenções destinadas a promover o bem-estar e um estilo de vida saudável no contexto universitário.

Rhipicephalus microplus: An overview of vaccine antigens against the cattle tick.

Rhipicephalus microplus, popularly known as the cattle tick, is the most important tick of livestock as it is responsible for significant economic losses. The use of chemical acaricides is still the most widely used control method despite its known disadvantages. Vaccination would be a safe alternative for the control of R. microplus and holds advantages over the use of chemical acaricides as it is environmental-friendly and leaves no residues in meat or milk. Two vaccines based on the Bm86 protein were commercialized, TickGARD® and Gavac®, with varying reported efficacies in different countries. The use of other vaccines, such as Tick Vac®, Go-Tick®, and Bovimune Ixovac® have been restricted to some countries. Several other proteins have been analyzed as possible antigens for more effective vaccines against R. microplus, including peptidases, serine proteinase inhibitors, glutathione S-transferases, metalloproteases, and ribosomal proteins, with efficacies ranging from 14% to 96%. Nonetheless, more research is needed to develop safe and efficient tick vaccines, such as the evaluation of the efficacy of antigens against other tick species to verify cross-reactivity and inclusion of additional antigens to promote the blocking of the infection and spreading of tick-borne diseases. This review summarizes the discoveries of candidate antigens for R. microplus tick vaccines as well as the methods used to test their efficacy.

Political architectures in the municipality of Varre-Sai (Brazil): for sustainabilities in 'specialty coffees' production management.

The coffee cultivation has historically had great importance in Rio de Janeiro's social-spatial organization, and it is once again in the spotlight of the state's economic scenario. The novelty is that the local production has been renewed, and, now, the state surpasses the old status of 'low-quality coffee producer' and achieves the 'specialty coffee' market which, in addition to quality, also values environmental, social and economic sustainabilities . This change has caused a series of transformations in the social-spatial and economic realities of some municipalities in the state of Rio de Janeiro. This article analyses the possible sustainabilities existing in the production process of this new coffee profile, based on the reality of the municipality of Varre-Sai, located in the northwest of Rio de Janeiro state. The objective is to find out the main actors and to elucidate the political network involved in this process.

Contrasting Structure and Bonding of a Copper-Rich and a Zinc-Rich Intermetalloid Cu/Zn Cluster.

Reaction of the Cu(I) sources, [Cu5](Mes)5 and [(iDipp)CuOtBu] (Mes = mesityl; iDipp = 1,3-bis(2,6-diisopropylphenyl)-1H-imidazol-2-ylidene) with the Zn(I) complex [Zn2](Cp*)2 leads to a mixture of intermetallic Cu/Zn clusters with a distribution of species that is dependent on the stoichiometric ratio of the reactants, the reaction time, as well as the temperature. Systematic and careful investigation of the product mixtures rendered the isolation of two new clusters possible, i.e., the Zn-rich, red cluster 1, [CuZn10](Cp*)7 = [Cu(ZnZnCp*)3(ZnCp*)4], as well as the Cu-rich, dark-green cluster 2 [Cu10Zn2](Mes)6(Cp*)2. Structure and bonding of these two species was rationalized with the help of density functional theory calculations. Whereas 1 can be viewed as an 18-electron Cu center coordinated to four ZnCp* and three ZnZnCp* one-electron ligands (with some interligand bonding interaction), compound 2 is better to be described as a six-electron superatom cluster. This unusual electron count is associated with a prolate distortion from a spherical superatom structure. This unexpected situation is likely to be associated with the ZnCp* capping units that offer the possibility to strongly bind to the top and the bottom of the cluster in addition to the bridging mesityl ligands stabilizing the Cu core of the cluster.

Edge, size, and shape effects on WS2, WSe2, and WTe2 nanoflake stability: design principles from an ab initio investigation.

An improved atomistic understanding of the W-based two-dimensional transition-metal dichalcogenides (2D TMDs) is crucial for technological applications of 2D materials, since the presence of tungsten endows these materials with distinctive properties. However, our atomistic knowledge on the evolution of the structural, electronic, and energetic properties and on the nanoflake stability of such materials is not properly addressed hitherto. Thus, we present a density functional theory (DFT) study of stoichiometric (WQ2)n nanoflakes, with Q = S, Se, Te, and n = 1,…,16, 36, 66, and 105. We obtained the configurations with n = 1,…,16 through the tree growth algorithm whereas the nanoflakes with n = 36, 66, and 105 were generated from fragments of 2D TMDs with an abundant diversity of shapes and edge configurations. We found that all the most stable nanoflakes present the same Q-terminated edge configuration. Furthermore, in isomers with n = 1,…,16 sizes, nanoflakes with triangular shapes and their derivatives, such as the rhombus geometry, define magic numbers, whereas for n > 16, triangular shapes were also found for the most stable structures, because they preserve the edge configuration. A strong modulation of the Hirshfeld charges, depending on chalcogen species and core or edge position, is also observed. The modulation of the Hirshfeld charge due to the nature of the W metal atoms makes the energetic 1D → 1T' transition of (WQ2)n differ in nanoflake size in relation to (MoQ2)n nanoflakes. Our analysis shows the interplay between edge configuration, coordination environment, and shape that determines the stability of nanoflakes, and allows us to describe design principles for stable 1T' stoichiometric nanoflakes of various sizes.

Hydrocellular Foam Versus Hydrocolloid Plate in the Prevention of Pressure Injuries.

INTRODUCTION: Pressure injury is one of the most prevalent skin injuries and a great challenge in the hospital environment. The implementation of preventive measures contributes to reducing its occurrence. OBJECTIVE: This study compares the protective effect of 2 adhesive dressings used in the prevention of pressure injuries in at-risk patients. MATERIALS AND METHODS: This case series was conducted at a university hospital in southeastern Brazil with 80 hospitalized adult patients at risk for pressure injuries, as per the Braden Scale for Predicting Pressure Sore Risk. Patients were randomized to preventive intervention with either hydrocellular foam (n = 40) or hydrocolloid plate (n = 40) dressing, which was applied to the intact skin over the sacrum and trochanters and changed weekly over 8 weeks. RESULTS: Of the patients, 56.5% were women, 64.5% were 60 years of age or older, 58.1% were admitted to an intensive care unit, and 63.9% were at high risk for pressure injuries. None of the patients developed a pressure injury. However, the presence of blanchable erythema, desquamation, pruritus, discomfort during dressing removal, and skin damage caused by the strong adhesiveness of the dressings were observed in both groups. In the hydrocolloid plate group, patients reported significantly more discomfort during dressing removal due to its strong adhesion to the skin (P = .004) than those in the hydrocellular foam group. CONCLUSIONS: Standard preventive measures combined with the use of either hydrocellular foam or hydrocolloid plate contributed to the prevention of pressure injuries in at-risk patients, with hydrocolloid plate being associated with significantly more discomfort during dressing removal.

The Mackay-Type Cluster [Cu43 Al12 ](Cp*)12 : Open-Shell 67-Electron Superatom with Emerging Metal-Like Electronic Structure.

The paramagnetic cluster [Cu43 Al12 ](Cp*)12 was obtained from the reaction of [CuMes]5 and [AlCp*]4 (Cp*=η5 -C5 Me5 ; Mes=mesityl). This all-hydrocarbon ligand-stabilized M55 magic atom-number cluster features a Mackay-type nested icosahedral structure. Its open-shell 67-electron superatom configuration is unique. Three unpaired electrons occupy weakly antibonding jellium states. The situation prefigures the formation of a conduction band, which is in line with the measured temperature-independent magnetism. Steric protection by twelve Cp* ligands suppresses the intrinsic polyradicalar reactivity of the Cu43 Al12 core.

Effects of a Physiotherapeutic Protocol in Respiratory Function, Aerobic Capacity and Quality of Life After Kidney Transplantation.

INTRODUCTION: Chronic kidney disease can lead to dysfunction of the respiratory, cardiac, and musculoskeletal systems, altering the body's metabolism. Renal transplantation and hospital physiotherapy, through specific protocols, can improve these dysfunctions. OBJECTIVES: This study evaluates the impact of a hospital physiotherapeutic protocol in quality of life (QoL), respiratory muscle strength, peak expiratory flow, and 6-minute walk test (6MWT) in the preoperative, first, and fifth days after renal transplantation. METHODS: We evaluated 39 patients who received a renal transplant at Clinics Hospital of University of Campinas for respiratory muscle strength, expiratory peak flow, and functional capacity by the 6MWT. The short form-36 quality of life questionnaire was applied to 12 patients. RESULTS: We observed a significant reduction in respiratory muscle strength and peak expiratory flow in the first postoperative day. On postoperative day 5, there was improvement in respiratory muscle strength and expiratory peak flow. However, aerobic capacity measured by 6MWT remained below predicted. Analysis of QoL showed an improvement in almost all analyzed domains after transplantation. CONCLUSION: A specific physiotherapeutic protocol applied early after transplantation provided recovery of respiratory muscle strength and QoL. However, longer training is necessary to obtain adequate aerobic rehabilitation.

NeuronRead, an open source semi-automated tool for morphometric analysis of phase contrast and fluorescence neuronal images.

Neurons are specialized cells of the Central Nervous System whose function is intricately related to the neuritic network they develop to transmit information. Morphological evaluation of this network and other neuronal structures is required to establish relationships between neuronal morphology and function, and may allow monitoring physiological and pathophysiologic alterations. Fluorescence-based microphotographs are the most widely used in cellular bioimaging, but phase contrast (PhC) microphotographs are easier to obtain, more affordable, and do not require invasive, complicated and disruptive techniques. Despite the various freeware tools available for fluorescence-based images analysis, few exist that can tackle the more elusive and harder-to-analyze PhC images. To surpass this, an interactive semi-automated image processing workflow was developed to easily extract relevant information (e.g. total neuritic length, average cell body area) from both PhC and fluorescence neuronal images. This workflow, named 'NeuronRead', was developed in the form of an ImageJ macro. Its robustness and adaptability were tested and validated on rat cortical primary neurons under control and differentiation inhibitory conditions. Validation included a comparison to manual determinations and to a golden standard freeware tool for fluorescence image analysis. NeuronRead was subsequently applied to PhC images of neurons at distinct differentiation days and exposed or not to DAPT, a pharmacological inhibitor of the γ-secretase enzyme, which cleaves the well-known Alzheimer's amyloid precursor protein (APP) and the Notch receptor. Data obtained confirms a neuritogenic regulatory role for γ-secretase products and validates NeuronRead as a time- and cost-effective useful monitoring tool.

Qualidade de vida e capacidade funcional em pacientes com úlcera arterial / Quality of life and functional ability in patients with arterial ulcers

Resumo Objetivo: Avaliar a Qualidade de Vida (QV) e a capacidade funcional em pacientes com Doença Arterial Periférica (DAP) e Úlceras Arteriais (UA). Metodologia: Estudo clínico descritivo e transversal, realizado no Sul de Minas Gerais, Brasil. Sessenta pacientes adultos alocados em três grupos -grupo DAP com UA, grupo DAP sem UA e grupo controle, sem DAP e sem UA- foram entrevistados, utilizando-se os questionários Health Assessment Questionnaire (HAQ) e o Short Form-36 Health Survey (SF-36) para medir a capacidade funcional e a QV, respectivamente. Para a comparação entre os grupos, foi utilizado o teste de Kruskal-Wallis. Resultados: Quarenta e dois participantes (70%) são mulheres e a idade média foi de 63 anos. Os pacientes com DAP, com ou sem UA, apresentaram incapacidade funcional significativamente maior que pacientes sem DAP (p < 0,01) nos componentes relacionados a deambulação, uso de utensílios domésticos, higiene e apreensão/sustentação de objetos. Os pacientes com DAP, com ou sem lesões, apresentaram SF-36 escores significativamente mais baixos -menor QV- nos domínios Capacidade funcional, Aspectos físicos, Dor corporal, Vitalidade, Aspectos sociais e Aspecto emocional do SF-36 em relação ao grupo controle (p < 0,001). Também foram observadas diferenças significativas (p < 0,001) entre o grupo controle e o grupo com DAP e UA nos domínios Estado geral de saúde e Saúde mental. Conclusão: Os pacientes com DAP, com ou sem úlcera, apresentaram redução na capacidade de realização de algumas atividades cotidianas, além de baixos níveis de QV quando comparados aos pacientes sem a doença.

Objetivo: Evaluar la Calidad de Vida (CV) y la capacidad funcional en pacientes con Enfermedad Arterial Periférica ( EAP) y Úlceras Arteriales (UA). Metodología: Estudio clínico descriptivo y transversal, realizado en el sur de Minas Gerais, Brasil. Sesenta pacientes adultos asignados en tres grupos -grupo EAP con UA, grupo EAP sin UA y grupo de control sin EAP y UA- fueron entrevistados, para lo cual se hizo uso de las escalas Health Assessment Questionnaire (HAQ) y el Short Form-36 Health Survey (SF-36) que evalúan la capacidad física y la calidad de vida, respectivamente. Para las comparaciones entre los grupos, se utilizó la prueba de Kruskal-Wallis. Resultados: Cuarenta y dos participantes (70%) son mujeres y la edad media fue de 63 años. Los pacientes con EAP, con o sin UA, presentaron limitación funcional significativamente mayor que los pacientes sin PAD (p < 0,01) en componentes relacionados con el andar, el uso de utensilios domésticos, la higiene y el alcance/agarre de objetos. Los pacientes con PAD, con o sin lesiones, tenían puntuaciones significativamente más bajas de SF-36 -CV inferior- en las dimensiones Función física, Rol físico, Dolor corporal, Vitalidad, Función social y Rol emocional en comparación con los pacientes del grupo control (p < 0,001). También se observaron diferencias significativas entre el grupo control y el grupo con EAP y au en las dimensiones Salud general y Salud mental. Conclusión: Los pacientes con EAP, con o sin úlcera, mostraron dificultad para realizar algunas actividades cotidianas, así como baja calidad de vida en comparación con los pacientes sin la enfermedad.

Objective: To assess Quality of Life (QOL) and functional ability in patients with Peripheral Arterial Disease (PAD) and Arterial Ulcers (AUS). Methodology: Descriptive and cross-sectional clinical study, conducted in Southern Minas Gerais, Brazil. Sixty adult patients allocated in three groups -group PAD with aus, group PAD without aus, and control group, without both PAD and aus- were interviewed using the scales Health Assessment Questionnaire (HAQ) and Short Form-36 Health Survey (SF-36), which assess physical disability and quality of live, respectively. The Krus-kal-Wallis test was used in order to compare the groups. Results: Forty-two participants (70%) are women, and the mean age was 63 years old. Patients with PAD, with or without aus, had significantly greater disability than patients without PAD (p < 0.01) on components related to walking, use of household utensils, hygiene, and reach/grip of objects. Patients with PAD, with or without lesions, reported significantly lower SF-36 scores -lower QOL- on Physical functioning, Role physical, Bodily pain, Vitality, Social functioning, and Role emotional domains, in comparison to patients from the control group (p < 0.001). Significant differences were also observed between the control group and the group with PAD and aus on the General health and Mental health domains. Conclusion: Patients with PAD, with or without AUS, reported difficulty in performing some activities of daily living and impaired QOL in comparison to patients without the disease.

Nitroxyl as a ligand in ruthenium tetraammine systems: a density functional theory study.

The properties of the free nitroxyl molecule and the nitroxyl ligand in Ru(ii) tetraammines (trans-[Ru(NH3)4(nitroxyl)(n)(L)](2+n) (n = nitroxyl charge; L = NH3, py, P(OEt)3, H2O, Cl(-) and Br(-))) were studied using density functional theory. According to the calculated conformational energies, HNO complexes are more stable than their deprotonated analogues, and the singlet configuration (trans-(1)[Ru(NH3)4(L)HNO](2+)) is lower in energy than the corresponding triplet (trans-(3)[Ru(NH3)4(L)HNO](2+)). An evaluation of the σ and π components of the L-Ru-HNO bond suggest that the increased stability of these orbitals and the enhanced contributions from the HNO orbitals correlate to shorter Ru-N(H)O distances and higher νRu-HNO stretching frequencies. The stability of the Ru-HNO bond was also evaluated through a theoretical kinetic study of HNO dissociation from trans-(1)[Ru(NH3)4(L)HNO](2+). The order of the Ru-HNO bonding stability in trans-(1)[Ru(NH3)4(L)HNO](2+) as a function of L was found to be as follows: H2O > Cl(-)∼ Br(-) > NH3 > py > P(OEt)3. This order parallels the order of the trans-effect and trans-influence series experimentally measured for L in octahedral complexes. The same trend was also observed using an explicit solvent model, considering the presence of both HNO and H2O molecules in the transition state. For this series, the calculated bond dissociation enthalpies for the Ru-HNO bonds are in the range 23.8 to 45.7 kcal mol(-1). A good agreement was observed between the calculated ΔG(‡) values for the displacement of HNO by H2O in trans-(1)[Ru(NH3)4(P(OEt)3HNO](2+) (23.4 kcal mol(-1)) and the available experimental data for the substitution reactions of trans[Ru(NH3)4(POEt)3(Lx)](2+) (19.4 to 24.0 kcal mol(-1) for Lx = isn and P(OET)3, respectively).

Health-related Quality of Life and Self-esteem Among Burn Patients.

Pyoderma gangrenosum is an unusual cause of skin ulcerations that wound specialists must be prepared to recognize. There is no diagnostic test since it is a diagnosis of exclusion, and if the disease is not recognized it can quickly become much worse. Pathergy, whereby a lesion begins or worsens due to trauma, such as a scrape, bite, debridement, surgery, or biopsy, is seen with pyoderma and requires special consideration. This case series and review will summarize the salient features of pyoderma and its treatment with an emphasis on the controversial role of surgery with pyoderma.

Expression of non-acetylatable lysines 10 and 14 of histone H4 impairs transcription and replication in Trypanosoma cruzi.

The histone H4 from Trypanosomatids diverged from other eukaryotes in the N-terminus, a region that undergoes post-translation modifications involved in the control of gene expression, DNA replication, and chromatin assembly. Nonetheless, the N-terminus of Trypanosoma cruzi histone H4 is mainly acetylated at lysine 4. The lysines 10 and 14 are also acetylated, although at less extent, increasing during the S-phase or after DNA damage, which suggests a regulatory function. Here, we investigated the roles of these acetylations by expressing non-acetylated forms of histone H4 in T. cruzi. We found that histone H4 containing arginines at positions 10 or 14, to prevent acetylation were transported to the nucleus and inserted into the chromatin. However, their presence, even at low levels, interfered with DNA replication and transcription, causing a significant growth arrest of the cells. The absence of acetylation also increased the amount of soluble endogenous histones H3 and H4 and affected the interaction with Asf1, a histone chaperone. Therefore, acetylation of lysines 10 and 14 of the histone H4 in trypanosomes could be required for chromatin assembly and/or remodeling required for transcription and replication.

Cyanate as an Active Precursor of Ethyl Carbamate Formation in Sugar Cane Spirit.

The thermodynamic and kinetic aspects of ethyl carbamate (EC) formation through the reaction between cyanate and ethanol were investigated. The rate constant values for cyanate ion decay and EC formation are (8.0 ± 0.4) × 10(-5) and (8.9 ± 0.4) × 10(-5) s(-1), respectively, at 25 °C in 48% aqueous ethanolic solution at pH 4.5. Under the investigated experimental conditions, the rate constants are independent of the ethanol and cyanate concentrations but increase as the temperature increases (ΔH1(⧧) = 19.4 ± 1 kcal/mol, ΔS1(⧧) = −12.1 ± 1 cal/K, and ΔG1(⧧) = 23.0 ± 1 kcal/mol) and decrease as the solution pH increases. According to molecular modeling (DFT) that was performed to analyze the reaction mechanism, the isocyanic acid (HNCO) is the active EC precursor. The calculated ΔG1(⧧), ΔH1(⧧), and ΔS1(⧧) values are in very good agreement with the experimental ones.

Characterization of Trypanosoma cruzi Sirtuins as Possible Drug Targets for Chagas Disease.

Acetylation of lysine is a major posttranslational modification of proteins and is catalyzed by lysine acetyltransferases, while lysine deacetylases remove acetyl groups. Among the deacetylases, the sirtuins are NAD(+)-dependent enzymes, which modulate gene silencing, DNA damage repair, and several metabolic processes. As sirtuin-specific inhibitors have been proposed as drugs for inhibiting the proliferation of tumor cells, in this study, we investigated the role of these inhibitors in the growth and differentiation of Trypanosoma cruzi, the agent of Chagas disease. We found that the use of salermide during parasite infection prevented growth and initial multiplication after mammalian cell invasion by T. cruzi at concentrations that did not affect host cell viability. In addition, in vivo infection was partially controlled upon administration of salermide. There are two sirtuins in T. cruzi, TcSir2rp1 and TcSir2rp3. By using specific antibodies and cell lines overexpressing the tagged versions of these enzymes, we found that TcSir2rp1 is localized in the cytosol and TcSir2rp3 in the mitochondrion. TcSir2rp1 overexpression acts to impair parasite growth and differentiation, whereas the wild-type version of TcSir2rp3 and not an enzyme mutated in the active site improves both. The effects observed with TcSir2rp3 were fully reverted by adding salermide, which inhibited TcSir2rp3 expressed in Escherichia coli with a 50% inhibitory concentration (IC50) ± standard error of 1 ± 0.5 µM. We concluded that sirtuin inhibitors targeting TcSir2rp3 could be used in Chagas disease chemotherapy.