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Microbial conversion of lignocellulosic biomass represents an alternative route for production of biofuels and bioproducts. While researchers have mostly focused on engineering strains such as Rhodotorula toruloides for better bisabolene production as a sustainable aviation fuel, less is known about the impact of the feedstock heterogeneity on bisabolene production. Critical material attributes like feedstock composition, nutritional content, and inhibitory compounds can all influence bioconversion. Further, the given feedstocks can have a marked influence on selection of suitable pretreatment and hydrolysis technologies, optimizing the fermentation conditions, and possibly even modifying the microorganism's metabolic pathways, to better utilize the available feedstock. This work aimed to examine and understand how variations in corn stover batches, anatomical fractions, and storage conditions impact the efficiency of bisabolene production by R. toruloides. All of these represent different facets of feedstock heterogeneity. Deacetylation, mechanical refining, and enzymatic hydrolysis of these variable feedstocks served as the basis of this research. The resulting hydrolysates were converted to bisabolene via fermentation, a sustainable aviation fuel precursor, using an engineered R. toruloides strain. This study showed that different sources of feedstock heterogeneity can influence microbial growth and product titer in counterintuitive ways, as revealed through global analysis of protein expression. The maximum bisabolene produced by R. toruloides was on the stalk fraction of corn stover hydrolysate (8.89 ± 0.47 g/L). Further, proteomics analysis comparing the protein expression between the anatomic fractions showed that proteins relating to carbohydrate metabolism, energy production, and conversion as well as inorganic ion transport metabolism were either significantly upregulated or downregulated. Specifically, downregulation of proteins related to the iron-sulfur cluster in stalk fraction suggests a coordinated response by R. toruloides to maintain overall metabolic balance, and this was corroborated by the concentration of iron in the feedstocks., One-Sentence Summary: This study elucidates the effects of different sources of corn stover on bisabolene production by engineered Rhodotorula toruloides, highlighting the importance of understanding feedstock variability to enhance bioprocess efficiency and economic outcomes., (Published by Oxford University Press on behalf of Society of Industrial Microbiology and Biotechnology 2024.)

Postprandial symptoms of neuroglycopenia after bariatric surgery may result as a consequence of endogenous hyperinsulinemic hypoglycemia (nesidioblastosis) not dumping syndrome. Pancreatectomy is an acceptable treatment for this condition. We present the video of a case of near-total distal robotic pancreactectomy for the treatment of nesidioblastosis after Roux-en-Y gastric bypass. Robotic pancreatectomy is an alternative to the treatment of nesidioblastosis after Roux-en-Y gastric bypass., Competing Interests: The authors declare that they have no conflicts of interest. Ethical Standards All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards. Inform Consent For this type of study, formal consent is not required.

Prosthetic mesh implants are commonly used to correct abdominal wall defects. However, success of the procedure is conditioned by an adequate inflammatory response to the device. We hypothesized that nitric oxide produced by nitric oxide synthase 2 (NOS2) and MMP-2 and -9 participate in response induced by mesh implants in the abdominal wall and, consequently, affect the outcome of the surgical procedure. In the first step, temporal inflammatory markers profile was evaluated. Polypropylene meshes were implanted in the peritoneal side of the abdominal wall of C57Black mice. After 2, 4, 7, 15, and 30 days, tissues around the mesh implant were collected and inflammatory markers were analyzed. In the second step, NOS2 activity was inhibited with nitro-L-arginine methyl ester (L-NAME). Samples were collected after 15 days (when inflammation was reduced), and the inflammatory and tissue remodeling markers were investigated. Polypropylene mesh implant induced a pro-inflammatory environment mediated by intense MMP-2 and -9 activities, NO release, and interleukin-1β production peaking in 7 days and gradually decreasing after 15 days. NOS2 inhibition increased MMP-2 activity and resulted in a higher visceral adhesion incidence at the mesh implantation site when compared with non-treated animals that underwent the same procedure. We conclude that NOS2-derived NO is crucial for adequate response to polypropylene mesh implant integration in the peritoneum. NO deficiency results in an imbalance between extracellular matrix deposition/degradation contributing to visceral adhesions incidence., (Copyright © 2012 Wiley Periodicals, Inc.)

Prosthetic meshes are commonly used to correct abdominal wall defects. However, the inflammatory reaction induced by these devices in the peritoneum is not completely understood. We hypothesized that nitric oxide (NO), produced by nitric oxide synthase 2 (NOS2) may modulate the response induced by mesh implants in the abdominal wall and, consequently, affect the outcome of the surgical procedure. Polypropylene meshes were implanted in the peritoneal side of the abdominal wall in wild-type and NOS2-deficient (NOS2(-/-)) mice. After 15 days tissues around the mesh implant were collected, and inflammatory markers (the cytokine interleukin 1β (IL-1β) and NO) and tissue remodeling (collagen and metalloproteinases (MMP) 2 and 9) were analyzed. The lack of NOS2-derived NO induced a higher incidence of visceral adhesions at the mesh implantation site compared with wild-type mice that underwent the same procedure (P<0.05). Additionally, higher levels of IL-1β were present in the mesh-implanted NOS2(-/-) animals compared with control and wild-type mice. Mesh implantation induced collagen I and III deposition, but in smaller amounts in NOS2(-/-) mice. MMP-9 activity after the surgical procedure was similarly increased in both groups. Conversely, MMP-2 activity was unchanged in mesh-implanted wild-type mice, but was significantly increased in NOS2(-/-) mice (P<0.01), due to decreased S-nitrosylation of the enzyme in these animals. We conclude that NOS2-derived NO is crucial for an adequate response to and integration of polypropylene mesh implants in the peritoneum. NO deficiency results in a prolonged inflammatory reaction to the mesh implant, and reduced collagen deposition may contribute to an increased incidence of visceral adhesions., (Copyright © 2011 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

Background: The use of prosthetic materials to reinforce the abdominal wall is associated with a low index of recurrence; however, intraperitoneal placement of a foreign body may lead to adhesions. The present investigation was designed to determine adhesion formation with commercially available meshes implanted laparoscopically in rabbits., Methods: Three different meshes were implanted laparoscopically in 24 rabbits: polypropylene (mesh A), polypropylene and sodium hyaluronate-carboxymethylcellulose (mesh B), and polypropylene and expanded polytetrafluoroethylene (mesh C). Sites of implantation for each mesh (the left lower quadrant, right lower quadrant, and lower midline) were randomly determined so that every rabbit had all 3 meshes implanted. All animals underwent diagnostic laparoscopy after 28 days to grade adhesions and histological analysis of inflammation., Results: Adhesions were noticed in 46 of the 72 meshes implanted (64%). The number of adhesions was higher for mesh C (87.5%) compared with meshes A (62.5%) and B (41.6%). The severity of adhesions was also higher for mesh C (grade I in 14, II in 6, and III in 1) compared with mesh A (grade I in 10, II in 4, and III in 1 case) and B (all of them grade II). Histological inflammatory reaction was classified as mild in 23 cases of mesh A, 15 of mesh B, and 23 of mesh C. A moderate reaction was found in 1 case of mesh A, 4 cases of mesh B, and 1 case of mesh C. Severe reaction was induced in 5 cases of mesh B. Mesh B induced a higher inflammatory reaction compared with the other meshes., Conclusions: All meshes induced adhesions of different grades. Mesh B had fewer adhesions and more intense inflammation them did the others.

Purpose: Compare, in a rabbit model, the inflammatory response and adhesions formation following surgical fixation of polypropilene and Vypro mesh in the inguinal preperitoneal space., Methods: Fourteen male New Zealand rabbits, weighing between 2.000 to 2.500 g were used. A midline incision was made and the peritoneal cavity was exposed. The 2.0 x 1.0 cm polypropylene mesh was fixed in the left flank and secured to the margins with 3-0 prolene in a separate pattern. In the right flank, a 2.0 x 1.0 cm Vypro II mesh was sewn in the same way. After the post surgical period, the animals were again anesthetized and underwent laparoscopic approach, in order to identify and evaluate adhesions degree. Both fixed prosthesis were excised bilaterally with the abdominal wall segment, including peritoneum, aponeurosis and muscle and sent to a pathologist., Results: Operative time ranged from 15 to 25 minutes and no difficulties in applying the mesh were found. From the 14 polypropylene meshes fixed to the intact peritoneum, 11 had adhesions to the abdominal cavity (78.6%). Concerning Vypro mesh, 12 animals developed adhesions from the 14 with mesh fixation (85.7%). Histological examination of tissues harvested revealed fibroblasts, collagen, macrophages and lymphocytes between the threads of the mesh., Conclusion: Polypropylene and Vypro mesh, when implanted in the peritoneal cavity of rabbits provoke similar amount of adhesions. Vypro mesh tissues had higher fibrosis resulting in better mesh incorporation to the abdominal wall.

Background and Objectives: Biliary leakage through the cystic duct stump due to clip dislodgement has been a concern since the advent of the laparoscopic cholecystectomy. The authors proposed a cadaveric model to test the safety of cystic duct clipping in a hypertensive biliary tract in healthy and cirrhotic livers., Methods: Twenty fresh cadavers were studied (5 cirrhotic, 15 healthy). Open cholecystectomy was performed and the cystic duct clipped with commercially available titanium clips. The distal common bile duct was catheterized to allow infusion of water and pressure measurement., Results: Increased pressure in the bile duct resulted in back diffusion into the liver, preventing reaching high-pressure levels. Only 1 clip was dislodged in this situation, in a cirrhotic liver with a large cystic duct. As a second experiment, the hepatic hilum was clamped to allow higher pressures of the biliary tree (500 mm Hg). In this situation, no clip was dislodged., Conclusions: We have established the safety of cystic duct clipping in healthy and cirrhotic livers; however, bigger clips or alternative methods to seal the duct may be necessary in larger ducts.

This paper deals with the impact of night work from a gender perspective, through a field study at a factory employing men and women on the night shift. It is based on data for hours of sleep over the course of several weeks, socio-demographic data, and job information, using a semi-structured interview. The methodology includes chronobiological aspects of sleep (mainly quantitative data) and workers' discourse concerning gender-related experiences in the day-to-night switch. Despite gender issues and differences in daily life, the switch is perceived quite vividly by both men and women, permeating several aspects of life, like health, leisure, studies, and intimate personal relations. Quantitative sleep analysis showed more severe effects of night work on women, especially those with children. Such sleep patterns were associated with different expectations among men and women, revealing gender issues that are essential for understanding the reality of individuals who work odd hours.

The study was performed to investigate possible alterations in oxygen consumption in an animal model with broad intestinal resection. Oxygen consumption and the thermal effect of a short meal were measured in rats subjected to short bowel syndrome. Four groups of rats were used. Group I was the control group, group II was sham operated, group III was submitted to 80% jejunum-ileum resection, and group IV was submitted to 80% jejunum-ileum resection with colon interposition. Ninety days after surgery, oxygen consumption was measured over a period of 6 h with the animals fasted overnight. The thermal effect of feeding was determined in another session of oxygen consumption measurement in animals fasted for 12 h. A 12-kcal meal was then introduced into the animal chamber and oxygen consumption was measured for a further 4 h. No differences in fasting oxygen consumption or in the thermal effect of the meal were detected among the groups studied. It is concluded that short bowel syndrome does not affect the overall energy expenditure of rats.

Background: We evaluated the possibility of video-endoscopic dissection of both internal thoracic arteries (rTAs) through the left thoracic approach and right gastroepiploic artery (GEA) via a small laparoscopic access, for use in minimally invasive coronary artery bypass surgery., Methods: The procedure was performed on twenty-two mongrel dogs. Three 10 mm ports were inserted in the left hemithorax to enable the introduction of a rigid 0-degree videoscope and forceps which allowed access to the left and right ITAs. For dissection of the GEA, one 10 mm and two 5 mm ports were inserted in the para-umbilical region., Results: The left and right ITAs and the GEA were easily visualized and dissection and complete mobilization was achieved without injury, which was checked by the presence of good blood flow. The ITAs and GEA were divided distally, exteriorized through a small left anterior thoracotomy and the length of these three grafts were able to reach all of the left coronary artery branches., Conclusions: We have demonstrated, in dogs, the feasibility of video-assisted dissection of both the left and right ITAs through the left thoracic approach, without sternotomy, avoiding the risks of sternal complications and expanding its use for all patients. Furthermore, a third arterial conduit (the RGA) can be used without requiring laparotomy.