Synthesis of Bifunctional Allylic Compounds by Using Cyclopropenes as Functionalized Allyl Equivalents.

The synthesis of uncommon bifunctional allylic derivatives bearing a silane and an alcohol within the same allylic framework is reported. This method relies on the coupling of hydrosilanes with substituted and functionalized cyclopropenes, which deliver the allyl fragment. Rhodium(II) catalysts provide regioselective access to vinyl carbene intermediates, which easily undergo Si-H bond insertions. The transformation occurs with complete atom economy and shows a remarkably broad scope, including a intramolecular version for the synthesis of cyclic O-Si-linked compounds as well as the synthesis of the corresponding allyl amines.

Zinc-Catalyzed Synthesis of Conjugated Dienoates through Unusual Cross-Couplings of Zinc Carbenes with Diazo Compounds.

Zinc-catalyzed selective cross-coupling of two carbene sources, such as vinyl diazo compounds and enynones, enabled the synthesis of conjugated dienoate derivatives. This reaction involved the unprecedented coupling of a zinc furyl carbene with vinyl diazo compounds through the γ-carbon. Alternatively, dienoates were also prepared by a commutative cross-coupling of zinc vinyl carbenes generated from cyclopropenes and simple diazo compounds.

Zinc-Catalyzed Synthesis of Allylsilanes by Si-H Bond Insertion of Vinyl Carbenoids Generated from Cyclopropenes.

Allylsilanes have long been recognized as valuable building blocks for organic synthesis. A zinc-catalyzed reaction of cyclopropenes and hydrosilanes provides a convenient route to these versatile unsaturated organosilanes. In this transformation, ZnBr2 serves as an efficient catalyst, allowing the generation of a zinc vinyl carbenoid intermediate, which is subsequently involved in a Si-H bond insertion. The process shows broad scope, and is amenable to substituted and functionalized cyclopropenes or the functionalization of polysiloxanes. Moreover, zinc-catalyzed carbene insertion into a Ge-H bond is reported for the first time.

Zinc-Catalyzed Functionalization of Si-H Bonds with 2-Furyl Carbenoids through Three-Component Coupling.

A three-component coupling of alk-2-ynals, 1,3-dicarbonyls and silanes is reported. ZnCl2 serves as an inexpensive and low-toxic catalyst for the overall transformation, which involves Knoevenagel condensation, cyclization, and carbene Si-H bond insertion. The process takes place with high atom economy in the absence of organic solvents and shows a broad scope. This reaction is also applicable to the functionalization of oligomeric siloxanes.

Biodiversity and Archeological Conservation Connected: Aragonite Shell Middens Increase Plant Diversity.

Natural and cultural heritage sites frequently have nonoverlapping or even conflicting conservation priorities, because human impacts have often resulted in local extirpations and reduced levels of native biodiversity. Over thousands of years, the predictable winter rains of northwestern Baja California have weathered calcium from the clam shells deposited by indigenous peoples in middens along the coast. The release of this calcium has changed soil properties, remediated sodic and saline soils, and resulted in a unique microhabitat that harbors plant assemblages very different from those of the surrounding matrix. Native plant biodiversity and landscape heterogeneity are significantly increased on the anthropogenic soils of these shell middens. Protection of this cultural landscape in the Anthropocene will further both archeological and biodiversity conservation in these anthropogenic footprints from the Holocene. Along these coasts, natural and cultural heritage priorities are overlapping and mutually beneficial.

Influência do laser arseneto de gálio e arseneto de gálio-alumínio e pomada cicatrizante sobre leucócitos sanguíneos de ratos Wistar após lesão cutânea / Influence of the gallium arsenide laser and gallium aluminum arsenide laser and healing ointment on blood leukocytes in Wistar rats after cutaneous lesion

O presente estudo avaliou os efeitos do laser arseneto de gálio-alumínio (GaAsAl), do laser arseneto de gálio (GaAs) e pomada cicatrizante DersaniÒ sobre leucócitos sanguíneos após realização de feridas cutâneas em ratos Wistar. Os parâmetros analisados foram os valores hematológicos dos animais. Foram utilizados 30 ratos Wistar, adultos jovens, machos, provenientes da Universidade Federal de Viçosa. Cinco feridas de 12 mm foram feitas na região dorsal do ratos. Os animais foram separados em 5 grupos, com 6 animais cada. Grupo 1: animais tratados com o laser GaAs (4J/cm2), grupo 2: laser GaAsAl (30J/cm2), grupo 3: laser GaAsAl (60J/cm2), grupo 4: foi usada pomada DersaniÒ grupo 5: solução salina (controle). As aplicações foram feitas diariamente durante 20 dias. Foi coletado sangue no primeiro e último dia do experimento e foi armazenado com anticoagulante. A contagem global de leucócitos foi feita utilizando câmera de Neubauer. A contagem diferencial foi feita através de esfregaço após coloração com Giemsa. A contagem global de leucócitos nos diferentes tratamentos não apresentou diferença significativa, exceto nos animais tratados com DersaniÒ em que houve aumento significativo no número de monócitos. Os tratamentos com salina e Laser GaAsAl 30J/cm2 também apresentaram aumento no número de neutrófilos.

This study evaluated the effect of the gallium aluminum arsenide laser (GaAsAl), gallium arsenide laser (GaAs) and healing ointment Dersani® on blood leukocytes after performing cutaneous incision in Wistar rats. The analyzed parameters were the hematological values of the animals. 30 Wistar rats, young, adults, males, from Federal University of Viçosa, MG were used. Five incisions (12 mm long) were made in the dorsal region of the rats. The animals were divided into five groups, with six animals each. Group 1: animals treated with the GaAs laser (4J/cm2); Group 2: GaAsAl laser (30 J/cm2); Group 3: GaAsAl laser (60 J/cm2); Group 4: the DersaniÒ ointment was used; Group 5: saline solution (control). Therapy was applied daily for a period of 20 days. Blood samplings were carried out on the first and last day of the experiment and stored with anticoagulant. Total leukocytes count was performed using a Neubauer camera. Differential counts of Giemsa-stained smears were made. Total leukocytes count did not show significant difference in any treatment, except in the animals treated with Dersani® that a significant increase in monocytes number was found. The treatment with saline and the GaAsAl (30 J/cm2) laser showed also an increase in the number of neutrophils.

Análise do tecido hepático de camundongos alimentados com dieta enteral contendo prebióticos e contaminadas com Klebsiella sp / Analysis of liver tissue of mice fed an enteral diet containing probiotics and infected with Klebsiella sp / Análisis del tejido del hígado de ratones alimentados con una dieta enteral que contiene probióticos e infectados con Klebsiella sp

Objetivo: Avaliou-se, neste trabalho, o efeito da administração de frutoligossacarídeo (FOS) e insulina, adicionados à dieta enteral, na translocação de Klebsiella sp. para o fígado de camundongos. Métodos: Camundongos albinos suiços, com quatro a seis semanas de vida divididos em três grupos. Os animais do grupo I (controle) receberam apenas dieta AIN93-G. No tratamento II, os animais receberam dieta enteral contendo FOS, insulina, antibiótico e corticóide. No tratamento III, os animais receberam antibiótico e corticóide, dieta enteral sem FOS e insulina. No quinto dia após o início de oferecimento das dietas, os animais dos tratamentos II e III foram alimentados com dieta enteral contaminada com, aproximadamente, 10 UFC/g de Klebisella pneumoniae. Dois animais de cada grupo foram eutanasiados 24h após o fornecimento da dieta contaminada. O fígado desses animais foi coletado assepticamente e mantido em solução fixadora para estudos histológicos. Resultados: Análises histológicas demonstraram características mais intensas de inflamação no fígado dos animais que foram imunodeprimidos com corticóide, alimentados com dieta enteral contaminada com K. pneumoniae e sem prebióticos, em relação aos animais imunodeprimidos que receberam dieta enteral com prebióticos contaminada com com K. pneumoniae. Conclusão: Dietas enterais contendo ingredientes prebióticos diminuíram o grau de lesões degenerativas no tecido hepático.

Objective: We evaluated in this study, the effect of a fructoligosaccharides (FOS) and insulin, added to the enteral diet on translocation of Klebsiella sp. to the liver of mice. Methods: Swiss albino mice, with four to six weeks of life divided into three groups. Animals in group I (control) received only diet AIN 93-G. In treatment II, animals received enteral diet containing FOS, insulin, antibiotics and steroids. In treatment III, animals given antibiotics and corticosteroids, enteral nutrition and FOS without insulin. On the fifth day after start offering the diets, the animals in treatments II and III were fed with enteral feeding contaminated with approximately 10 CFU/g Klebisella pneumoniae. Two animals from each group were euthanized 24 hours after the diet contaminated. The liver of these animals were collected aseptically and kept in fixative solution for histological studies. Results: Histological analysis showed features of more intense inflammation in the liver of animals that were immunosuppressed with corticosteroids, enteral feeding on contaminated with K. pneumoniae and without probiotics, for immunosuppressed animals that received enteral feeding with prebiotics-contaminated with K. pneumoniae. Conclusion: Enteral diets containing prebiotic ingredients decreased the degree of degenerative lesions in liver tissue.

Objetivo: Se evaluó en este estudio, el efecto de una fructoligosaccharides (FOS) y la insulina, sumado a la dieta enteral en la translocación de Klebsiella sp. para el hígado de ratones. Métodos: ratones albino suizo, con cuatro a seis semanas de vida dividido en tres grupos. Animales en el grupo I (control) recibió dieta sólo AIN 93-G. En el tratamiento II, los animales recibieron la dieta enteral que contiene FOS, insulina, antibióticos y esteroides. En el tratamiento III, los animales que recibieron antibióticos y corticosteroides, la nutrición enteral y FOS sin insulina. En el quinto día comenzará después de ofrecer las dietas, los animales en los tratamientos II y III fueron alimentados con la alimentación enteral contaminados con aproximadamente 10 UFC/g Klebisella pneumoniae. Dos animales de cada grupo se sacrificaron 24 horas después de la dieta contaminada. El hígado de estos animales fueron recogidos asépticamente y se mantienen en solución fijadora para estudios histológicos. Resultados: El análisis histológico demostró características de más intensa inflamación en el hígado de animales que fueron inmunodeprimidos con corticosteroides, la nutrición enteral en contaminadas con K. pneumoniae y sin probióticos, por inmunodeprimidos animales que recibieron alimentación enteral con prebióticos contaminados con K. pneumoniae. Conclusión: enteral con dietas que contenían ingredientes prebióticos redujo el grado de lesiones degenerativas en el tejido hepático.