Genetic modification of acetogens and optimization of fermentation process in C1-gas bioconversion / 生物工程学报

The current linear economy model relies on fossil energy and increases CO2 emissions, which contributes to global warming and environmental pollution. Therefore, there is an urgent need to develop and deploy technologies for carbon capture and utilization to establish a circular economy. The use of acetogens for C1-gas (CO and CO2) conversion is a promising technology due to high metabolic flexibility, product selectivity, and diversity of the products including chemicals and fuels. This review focuses on the physiological and metabolic mechanisms, genetic and metabolic engineering modifications, fermentation process optimization, and carbon atom economy in the process of C1-gas conversion by acetogens, with the aim to facilitate the industrial scale-up and carbon negative production through acetogen gas fermentation.

Successful medical drainage and surgical treatment for vertebral osteomyelitis and bilateral psoas abscess with gas formation caused by klebsiella pneumoniae in a diabetic patient

SUMMARY OBJECTIVE: We describe the case of a diabetic patient who developed vertebral osteomyelitis and bilateral psoas abscess with gas formation due to klebsiella pneumoniae. METHODS: A 64-year-old woman with a 4-year history of type-2 diabetes mellitus was admitted to the Emergency Department. The subject had a 2-day history of high-grade fever associated with chills and a 5-hour history of consciousness. She received empirical treatment with febrifuge, after which her fever decreased. RESULTS: Her fever recurred after an interval of three hours. A computed tomography scan of the abdomen revealed vertebral osteomyelitis and bilateral psoas muscle abscess with gas formation. Blood culture and purulent fluid described the growth of the Klebsiella pneumoniae. The patient received antibiotic therapy and bilateral drainage therapy after the drainage catheter was placed into the abscess cavity by CT-guidance. Due to the serious damage to the vertebral column and permanent pain, the patient underwent minimally invasive internal spinal fixation and recovered successfully. CONCLUSION: A case of vertebral osteomyelitis and bilateral psoas abscess with gas formation caused by Klebsiella pneumoniae in a diabetic patient. Antibiotic therapy, drainage, and minimally invasive internal spinal fixation were performed, which enabled a good outcome.

RESUMO OBJETIVO: Descrever o caso de uma paciente diabética que desenvolveu osteomielite vertebral e abcesso bilateral do psoas com formação de gás causada por klebsiella pneumoniae. MÉTODOS: Uma mulher de 64 anos de idade, com 4 anos de histórico de diabetes mellitus tipo 2, foi admitida no Serviço de Emergência. A paciente apresentava um quadro de dias de febre alta acompanhada de calafrios e um histórico de 5 horas de consciência. Ela recebeu tratamento empírico com antitérmico, após o qual a febre diminuiu. RESULTADOS: A febre retornou após um intervalo de três horas. Uma tomografia computadorizada do abdome revelou osteomielite vertebral e abcesso bilateral do músculo psoas com formação de gás. A cultura do sangue e o fluido purulento revelaram o crescimento de Klebsiella pneumoniae. A paciente recebeu antibióticos e terapia de drenagem bilateral após o cateter de drenagem ser posicionado na cavidade do abscesso com auxílio de TC. Devido a sérios danos à coluna vertebral e a dor permanente, a paciente foi submetida à fixação vertebral interna minimamente invasiva e recuperou-se com sucesso. CONCLUSÃO: Um caso de osteomielite vertebral e abscesso do psoas bilateral com a formação de gás causada por Klebsiella pneumoniae em uma paciente diabética. Antibioticoterapia, drenagem e fixação vertebral interna minimamente invasiva foram realizadas, o que permitiu um bom resultado.

A Case of Successful Treatment of Portal Venous Gas Caused by Acute Pancreatitis / 대한소화기학회지

Hepatic portal venous gas (HPVG) has been considered a rare entity associated with a poor prognosis. Portal vein gas is most commonly caused by mesenteric ischemia but may have a variety other causes. HPVG can be associated with ischemic bowel disease, inflammatory bowel disease, intra-abdominal abscess, small bowel obstruction, acute pancreatitis, and gastric ulcer. Because of high mortality rate, most HPVG requires emergent surgical interventions and intensive medical management. We experienced a case of hepatic portal venous gas caused by acute pancreatitis and successfully treated with medical management.

The southern Brazilian grassland biome: soil carbon stocks, fluxes of greenhouse gases and some options for mitigation / Campos do sul do Brasil: estoques de carbono no solo, fluxos de gases de efeito estufa e algumas opções para mitigação

The southern Brazilian grassland biome contains highly diverse natural ecosystems that have been used for centuries for grazing livestock and that also provide other important environmental services. Here we outline the main factors controlling ecosystem processes, review and discuss the available data on soil carbon stocks and greenhouse gases emissions from soils, and suggest opportunities for mitigation of climatic change. The research on carbon and greenhouse gases emissions in these ecosystems is recent and the results are still fragmented. The available data indicate that the southern Brazilian natural grassland ecosystems under adequate management contain important stocks of organic carbon in the soil, and therefore their conservation is relevant for the mitigation of climate change. Furthermore, these ecosystems show a great and rapid loss of soil organic carbon when converted to crops based on conventional tillage practices. However, in the already converted areas there is potential to mitigate greenhouse gas emissions by using cropping systems based on no soil tillage and cover-crops, and the effect is mainly related to the potential of these crop systems to accumulate soil organic carbon in the soil at rates that surpass the increased soil nitrous oxide emissions. Further modelling with these results associated with geographic information systems could generate regional estimates of carbon balance.

Os campos do sul do Brasil são ecossistemas naturais com alta diversidade e têm sido há séculos importantes para a atividade pastoril e para outros importantes serviços ambientais. Este trabalho aponta os principais fatores que controlam os processos ecossistêmicos, revisa e discute os dados disponíveis sobre os estoques de carbono no solo e as emissões de gases de efeito estufa dos solos, e sugere oportunidades de mitigação das mudanças climáticas. A pesquisa sobre as emissões de carbono e gases de efeito estufa nos campos do sul do Brasil é recente e os resultados são ainda fragmentados. Os dados disponíveis indicam que os ecossistemas campestres naturais manejados adequadamente contêm estoques importantes de carbono orgânico no solo e, portanto, sua conservação é relevante para a mitigação das mudanças climáticas. Além disso, esses ecossistemas apresentam uma grande e rápida perda de carbono orgânico do solo quando convertidos para lavouras com preparo convencional do solo. No entanto, nas áreas já convertidas, há potencial para mitigar as emissões de gases de efeito estufa por meio de sistemas de cultivo usando plantio direto e rotações de culturas baseadas em plantas de cobertura de solo. O efeito está relacionado principalmente ao potencial desses sistemas de cultivo para acumular matéria orgânica do solo em taxas que superam o aumento das emissões de óxido nitroso. O uso de modelos com esses resultados associados aos sistemas de informação geográfica poderá gerar estimativas regionais de balanço de carbono.

Treatment of spent wash in anaerobic mesophilic suspended growth reactor (AMSGR).

Approximately 400 KL of spent wash or vinasse per annum is generated at an average COD concentration of 100,000 mg/l, by over 250 distilleries in India. There is an urgent need to develop, assess and use ecofriendly methods for the disposal of this high strength wastewater. Therefore, an attempt was made to investigate a few aspects of anaerobic digestion of spent wash collected from a distillery. The study was carried out in a 4 L laboratory scale anaerobic mesophilic suspended growth reactor. After the successful startup, the organic loading was increased stepwise to assess the performance of the reactor. During the study period, biogas generated was recorded and the maximum gas generated was found to be 16.9 L at an Organic Loading Rate (OLR) of 38 g COD/L. A 500% increase in the Volatile Fatty Acid (VFA) concentration (2150 mg/L) was observed, when the OLR was increased from 38 to 39 g COD/L. During the souring phase the removal of COD, Total Solids (TS) and Volatile Solids (VS) were in the order of 52%, 40% and 46% respectively. The methane content in the biogas varied from 65% to 75%.

Gas-producing brain abscess

A case of a known psychiatric patient who presented with rapid neurological deterioration is reported. Neuroimaging revealed a gas-producing brain abscess in left parietal lobe with a contiguous focus of infection in the adjacent bone and scalp initiated by obsessive scalp scratching. On complete surgical excision of abscess, followed by culturebased antibiotic therapy, a good neurological recovery was achieved with minimal residual deficits at follow-up

Mechanism of gas absorption from closed cavities in the living body

El intercambio gaseoso y la variación de volumen en cavidades cerradas colapsables fueron estudiados mediante un modelo experimental de cavidades artificialmente cerradas. Se tomaron 70 perros en los cuales se procedió a canular el bronquio del lóbulo inferior izquierdo y se lo insufló con aire. Los estudios se llevaron a cabo en dos grupos de animales; uno de ellos (n = 40) con irrigación de la arteria pulmonar del lóbulo con sangre arterial y el otro grupo (n = 30) con sangre venosa mixta. Se procedió a determinar la composición del gas insuflado cada 15 minutos durante dos horas. Los resultados mostraron un rápido incremento de la PCO2 a los 15 minutos que luego seguía aumentando más lentamente hasta los 30 minutos. La PO2 disminuía rápidamente durante los primeros 15 minutos y luego mostraba un lento descenso. En cuanto a la reabsorción del aire insuflado se observaron diferencias entre los irrigados con sangre venosa y con sangre arterializada. En los primeros se vió, a los 60 minutos una absorción del 40%, mientras que en los otros fue del 20%. La absorción se acercaba a cero, cuando a los perros arterializados se los ventilaba con CO2 al 5%. Estos datos contribuyen al conocimiento de la conducta de los gases ocluidos, en situaciones clínicas como la atelectasia y el neumotórax y muestran la tendencia de la concentración de los gases de la cavidades confinadas a igualarse con la de los gases de la sangre que perfunde esas cavidades a una velocidad que está en relación con los gradientes y en mucho menor grado con las condiciones viscoelásticas de la pared alveolar