New Papiliotrema laurentii UFV-1 strains with improved acetic acid tolerance selected by adaptive laboratory evolution.

The production of yeast oil from lignocellulosic biomasses is impaired by inhibitors formed during the pretreatment step, mainly acetic acid. Herein, we applied Adaptive Laboratory Evolution (ALE) to select three Acetic acid Tolerant Strains (ATS) of P. laurentii UFV-1. Different phenotypes emerged alongside evolution. The ATS II presented trade-offs in the absence of acetic acid, suggesting that it displays a specialized phenotype of tolerance to growth on organic acids. On the other hand, ATS I and ATS III presented phenotypes associated with the behavior of generalists. ATS I was considered the most promising evolved strain as it displayed the oleaginous phenotype in all conditions tested. Thus, we applied whole-genome sequencing to detect the mutations that emerged in this strain during the ALE. We found alterations in genes encoding proteins involved in different cellular functions, including multidrug resistance (MDR) transporters, energy metabolism, detoxification, coenzyme recycling, and cell envelope remodeling. To evaluate acetic acid stress responses, both parental and ATS I strains were cultivated in chemostat mode in the absence and presence of acetic acid. In contrast to ATS I, the parental strain presented alterations in the cell envelope and cell size under acetic acid stress conditions. Furthermore, the parental strain and the ATS I presented differences regarding acetic acid assimilation. Contrary to the parental strain, the ATS I displayed an increase in unsaturated fatty acid content irrespective of acetic acid stress, which might be related to improved tolerance to acetic acid. Altogether, these results provided insights into the mechanisms involved with the acetic acid tolerance displayed by ATS I and the responses of P. laurentii to this stressful condition.

Pinealectomia em ratas Wistar (Rattus norvegicus albinus): descrição de um novo método cirúrgico / Pinealectomy in Wistar rats (Rattus norvegicus albinus): Description of a new surgical method

A necessidade de manejo adequado antes, durante e após a implementação de procedimentos em animais de laboratório é essencial para proporcionar bem-estar. Portanto, no presente trabalho, objetivou-se padronizar uma nova técnica de pinealectomia em ratas Wistar. Trinta fêmeas nulíparas aos 90 dias de idade foram submetidas à anestesia dissociativa. Após a tricotomia e a assepsia, realizou-se uma incisão na linha média dorsal da cabeça. Com um micromotor e uma broca de aço PM 03, realizou-se a craniotomia; a glândula pineal foi removida por intermédio de um fórceps cápsula arruga. Em seguida, o fragmento ósseo foi recolocado em seu lugar de origem, e a pele aproximada por pontos simples. Finalizado o procedimento cirúrgico, foi realizada antibioticoterapia e soroterapia parenteral. O acompanhamento diário dos animais não evidenciou nenhum comprometimento da ferida operatória com padrão de cicatrização por primeira intenção. Os animais apresentaram normalidade de atos fisiológicos, como alimentação, defecação e micção, assim como socialização com o grupo. Técnicas cirúrgicas vêm sendo realizadas com o desenvolvimento das pesquisas envolvendo a glândula pineal. A técnica ideal para pinealectomia consiste no pouco sangramento, na curta duração da cirurgia e na nitidez da glândula pineal, diminuindo a probabilidade de acidentes neurológicos. Considerando-se os resultados obtidos ao longo do desenvolvimento experimental e clínico, o aprimoramento da técnica cirúrgica utilizando a broca PM03 associada ao fórceps cápsula arruga foi exímio na pesquisa científica da pinealectomia de ratas Wistar em virtude da rapidez e praticidade alcançadas. Tem-se a perspectiva de que este artigo sirva de subsídio para o aprimoramento e a otimização do modelo experimental para posteriores estudos acerca de pesquisas com a glândula pineal e, assim, maior compreensão de sua complexidade sobre todos os sistemas do organismo.

The need for adequate management before, during and after procedures involving laboratory animals is essential to their wellbeing. Thus, the aim of the present study was to standardize a novel method of pinealectomy in Wistar rats. Thirty nullipara females aged 90 days were submitted to dissociative anesthesia. Following fur removal and asepsis, an incision was performed along the dorsal line of the head. Craniotomy was performed with a mini-drill and PM 03 stainless steel drill bit. The pineal gland was removed using a serrated capsule forceps. The bone fragment was replaced and the skin was sutured with simple stitches. The surgical procedure was finalized with antibiotic therapy parenteral serotherapy. Daily follow up was performed and no animal demonstrated any compromised surgical wound with first intention wound healing. The animals exhibited normal physiological acts (feeding, defecation, urination and group socialization). Surgical techniques were performed with the development of research involving the pineal gland. The ideal pinealectomy method consists of little bleeding, a short surgery and a clear view of the pineal gland, thereby diminishing the probability of neurological accidents. Considering the results obtained through the experimental and clinical development, the perfection of the surgical technique involving the PM03 drill bit and serrated capsule forceps was successful in scientific research involving pinealectomy of Wistar rats in terms of quickness and practicality. This article can assist in the optimization of experimental models for subsequent studies involving the pineal gland and the understanding of its complexity over all organism systems.

Avaliaçäo do processo cicatricial utilizando Staphysagria e penicilina após rumenotomia experimental em caprinos / Evaluation of the healing process using Staphisagria and Penicilin after experimental \"rumetomia\"in caprinos

Com o objetivo de se avaliar a evoluçäo do processo cicatricial em caprinos submetidos a rumenotomia e tratados, no pós-cirúrgico, com Penicilina Benzantina e Staphisagria 6CH, 30 fêmeas adultas, sem raça definida, aparentemente sadias após exame clínico, foram divididas em tres grupos constituídos de dez animais.Após adaptaçäo às condiçöes de manejo, os animais foram submetidos a rumenotomia experimental e diariamente avaliados até o décimo quarto dia