Delivery of human apolipoprotein (apo) E to liver by an [E1(-), E3(-), polymerase(-), pTP(-)] adenovirus vector containing a liver-specific promoter inhibits atherogenesis in immunocompetent apoE-deficient mice

Recombinant adenovirus (rAd)-mediated apoE gene transfer to the liver of apoE(-/-) mice is anti-atherogenic. However, first generation rAd vectors were associated with immune clearance of transduced hepatocytes, while an improved [E1(-), E3(-) polymerase(-)] adenovirus vector that persisted in the liver, had transient effects due to cellular shutdown of the cytomegalovirus (CMV) promoter (Ad-CMV-apoE). Here, we utilise an improved class of rAd vector with multiple deletions in the E1, E3, polymerase and pTP (pre-terminal protein) genes, which contains a modular synthetic liver-specific promoter (LSP) to drive expression of the human apoE cDNA (Ad-LSP-apoE) for hepatic gene transfer. Approximately 1 year old apoE(-/-) mice were injected intravenously with 4x10(10) virus particles of either Ad-LSP-apoE or Ad-CMV-apoE. Animals were monitored for plasma apoE, total plasma cholesterol and plasma lipoprotein distribution. The effect of Ad-LSP-apoE on atheroma progression was assessed in animals killed at 8 and 28 weeks after the injections. Ad-LSP-apoE vector administration gave sustained, though low, levels of plasma apoE throughout the study period without inducing a humoral immune response, but failed to reduce plasma cholesterol or normalize the adverse lipoprotein profile. Animals killed 8 weeks after the injections, demonstrated no significant retardation of atherosclerosis, whereas aortic lesions in those killed at 28 weeks were significantly reduced by 30% ( P< 0.006) compared to untreated animals. In summary, the combination of a multiply deleted rAd vector with a liver-specific promoter provided sustained low levels of plasma apoE, resulting in significant retardation of aortic atherosclerotic lesions

Retardation of atherosclerosis in immunocompetent apolipoprotein (apo) E-deficient mice followingliver-directed administration of a [E1-, E3-,polymerase-] adenovirus vector containing the elongation factor-1a promoter driving expression of human apoE cDNA

Although gene transfer of human apolipoprotein E (apoE), a 34-kDa circulating glycoprotein, to the liver of apoEdeficient(apoE-/-) mice using recombinant adenoviral vectors (rAd) is antiatherogenic, its full therapeutic potentialhas yet to be realized. First generation vectors led to immune clearance of transduced hepatocytes, while animproved vector with adenovirus regions E1, E3 and DNA polymerase deleted also had transient effects due tocellular shutdown of the cytomegalovirus (CMV) promoter. Here, we have studied an alternative promoter from thecellular elongation factor 1a (EF-1a) gene, injecting 6-8 week old apoE-/- mice intravenously with 2x1010 virusparticles (vp) of the [E1-, E3-, polymerase-] rAd vector Ad-EF1·-apoE. Plasma apoE levels were low (18-55 ng/ml)and failed to reduce plasma cholesterol or normalize the adverse lipoprotein profile. By contrast, thehyperlipidaemic phenotype of apoE-/- mice treated with Ad-CMV-apoE (2x1010 vp) was transiently normalized.Nevertheless, at termination (265 days) the aortic lesion areas in animals given Ad-EF1·-apoE were significantlyreduced by 15% (P<0.05) compared to untreated animals, a decrease approaching that in Ad-CMV-apoE-treatedmice (23%; P<0.02). Importantly, the attenuation of apoE transgene expression noted with the CMV promoter wasabsent with the EF-1a promoter, which gave relatively sustained, albeit low, levels of plasma apoE throughout thestudy period

Apolipoprotein E delivery by peritoneal implantation of encapsulated recombinant cells improves the hyperlipidaemic profile in apoE-deficient mice

Plasma apolipoprotein E (apoE) is a 34-kDa polymorphic protein which has atheroprotective actions by clearing remnant lipoproteins and sequestering excess cellular cholesterol. Low or dysfunctional apoE is a risk factor for hyperlipidaemia and atherosclerosis, and for restenosis after angioplasty. Here, in short-term studies designed to establish proof-of-principle, we investigate whether encapsulated recombinant Chinese hamster ovary (CHO) cells can secrete wild-type apoE3 protein in vitro and then determine whether peritoneal implantation of the microcapsules into apoE-deficient (apoE(-/-)) mice reduces their hypercholesterolaemia.Recombinant CHO-E3 cells were encapsulated into either alginate poly-L-lysine or alginate polyethyleneimine/polybrene microspheres. After verifying stability and apoE3 secretion, the beads were then implanted into the peritoneal cavity of apoE(-/-) mice; levels of plasma apoE3, cholesterol and lipoproteins were monitored for up to 14 days post-implantation.Encapsulated CHO-E3 cells continued to secrete apoE3 protein throughout a 60-day study period in vitro, though levels declined after 14 days. This cell-derived apoE3 was biologically active. When conditioned medium from encapsulated CHO-E3 cells was incubated with cultured cells pre-labelled with [H-3]-cholesterol, efflux of cholesterol was two to four times greater than with normal medium (at 8 h, for example, 7.4+/-0.3% vs. 2.4+/-0.2% of cellular cholesterol; P<0.001). Moreover, when secreted apoE3 was injected intraperitoneally into apoE(-/-) mice, apoE3 was detected in plasma and the hyperlipidaemia improved. Similarly, when alginate polyethyleneimine/polybrene capsules were implanted into the peritoneum of apoE(-/-) mice, apoE3 was secreted into plasma and at 7 days total cholesterol was reduced, while atheroprotective high-density lipoprotein (HDL) increased. In a second study, apoE was detectable in plasma of five mice treated with alginate poly-L-lysine beads, 4 and 7 days post-implantation, though not at day 14. Furthermore, their hypercholesterolaemia was reduced, while HDL was clearly elevated in all mice at days 4 and 7 (from 18.4+/-6.2% of total lipoproteins to 31.1+/-6.8% at 7 days; P<0.001); however, these had rebounded by day 14, possibly due to the emergence of anti-apoE antibodies.We conclude that microencapsulated apoE-secreting cells have the potential to ameliorate the hyperlipidaemia of apoE deficiency, but that the technology must be improved to become a feasible therapeutic to treat atherosclerosis. (C) 2004 Elsevier B.V. All rights reserved

TURBOMACHINERY FOR HIGH CO2 APPLICATION: CHALLENGES, OBSTACLES AND LESSON LEARNT

Case StudiesTurbomachinery is the heart of any platform, which generates power and compresses gas. However, the current practices of turbomachinery are entangled with various challenges and obstacles, which eventually affect the overall performance of the platform. Hence, this paper aims at appraising the challenges and obstacles in turbomachinery application for high CO2 application. This paper aims to achieve objectives: (1) reviewing the oil and gas industry in terms of its operation and project execution; (2) determining the basic attributes of turbomachinery as well as the challenges and obstacles entangling its execution; and (3) proposing the solutions to these challenges and obstacles. It is found that stabilized process requirement and constant flow; subsurface uncertainties; production decline; selection process; specification and standard variations; contractual delivery; human factor; after sales support and services; and expenditure are listed among the challenges and obstacles in executing turbomachinery project for oil and gas. The findings of this paper would technically contribute to the project management elements of turbomachinery project execution and assist the management team particularly on the client/consultant side in efficiently and effectively manage the turbomachinery project execution via the prediction of challenges and obstacles. This case study presents the issues encountered, solutions implemented, results mitigation, lessons learnt, and technical replication based on two high CO2 application projects

Melaena with Peutz-Jeghers syndrome: a case report

Introduction: Peutz-Jeghers syndrome (PJS) is a rare familial disorder characterised by mucocutaneous pigmentation, gastrointestinal and extragastrointestinal hamartomatous polyps and an increased risk of malignancy. Peutz-Jeghers polyps in the bowel may result in intussusception. This complication usually manifests with abdominal pain and signs of intestinal obstruction. Case Presentation: We report the case of a 24-year-old Caucasian male who presented with melaena. Pigmentation of the buccal mucosa was noted but he was pain-free and examination of the abdomen was unremarkable. Upper gastrointestinal endoscopy revealed multiple polyps. An urgent abdominal computed tomography (CT) scan revealed multiple small bowel intussusceptions. Laparotomy was undertaken on our patient, reducing the intussusceptions and removing the polyps by enterotomies. Bowel resection was not needed. Conclusion: Melaena in PJS needs to be urgently investigated through a CT scan even in the absence of abdominal pain and when clinical examination of the abdomen shows normal findings. Although rare, the underlying cause could be intussusception, which if missed could result in grave consequences

ADAPTATION OF REMOTE AND AUTONOMOUS OPERATION (RAO) FOR ROTATING EQUIPMENT OF PETRONAS FACILITIES

Technical BriefsThe Oil and Gas industry is increasingly facing with more complex and hazardous operations. This is resultant from integration with a more complex feed and product properties as well as requirement for operation in harsher environment. At the same time, a much stronger Environmental regulation is currently enforced which demands strict adherence and compliance by all Operating Assets/Facilities. At the same time, technology has caught up rapidly in the last few years. More industries have started to embrace automation as a safety and productivity enabler and as a critical factor in running business and operation. The center of attention to this shift is automation of Rotating Equipment covering broad range from Turbomachinery down until a Potable Water Pump. Network communication enhancement via 5G technology has allowed remote operations and control technology able to be safely deployed. The new norm of Remote and Autonomous Operation (RAO) via Artificial Intelligence, Machine Learning, Digitalization effort as well as Digital Twins are also increasingly being adopted to allow for better performance monitoring, remote trouble shooting, predictive and prescriptive ability for Rotating Equipment. As proven in many industries and sector, PETRONAS have also successfully embarked on remote and autonomous operation journey for its Rotating Equipment fleet which will add clear value: it can improve safety, increase production efficiency, and lower maintenance costs. Although, implementing autonomous systems may also expose and presents new challenges such as cyber security and safety risks, the obvious advantage supersedes the risk which needs to be managed accordingly. This paper explains the challenges, the lesson learnt and PETRONAS approach in adapting RAO for Rotating Equipment

Spina bifida-predisposing heterozygous mutations in Planar Cell Polarity genes and Zic2 reduce bone mass in young mice

Fractures are a common comorbidity in children with the neural tube defect (NTD) spina bifida. Mutations in the Wnt/planar cell polarity (PCP) pathway contribute to NTDs in humans and mice, but whether this pathway independently determines bone mass is poorly understood. Here, we first confirmed that core Wnt/PCP components are expressed in osteoblasts and osteoclasts in vitro. In vivo, we performed detailed µCT comparisons of bone structure in tibiae from young male mice heterozygous for NTD-associated mutations versus WT littermates. PCP signalling disruption caused by Vangl2 (Vangl2Lp/+) or Celsr1 (Celsr1Crsh/+) mutations significantly reduced trabecular bone mass and distal tibial cortical thickness. NTD-associated mutations in non-PCP transcription factors were also investigated. Pax3 mutation (Pax3Sp2H/+) had minimal effects on bone mass. Zic2 mutation (Zic2Ku/+) significantly altered the position of the tibia/fibula junction and diminished cortical bone in the proximal tibia. Beyond these genes, we bioinformatically documented the known extent of shared genetic networks between NTDs and bone properties. 46 genes involved in neural tube closure are annotated with bone-related ontologies. These findings document shared genetic networks between spina bifida risk and bone structure, including PCP components and Zic2. Genetic variants which predispose to spina bifida may therefore independently diminish bone mass

Do red deer stags (Cervus elaphus) use roar fundamental frequency (F0) to assess rivals?

It is well established that in humans, male voices are disproportionately lower pitched than female voices, and recent studies suggest that this dimorphism in fundamental frequency (F0) results from both intrasexual (male competition) and intersexual (female mate choice) selection for lower pitched voices in men. However, comparative investigations indicate that sexual dimorphism in F0 is not universal in terrestrial mammals. In the highly polygynous and sexually dimorphic Scottish red deer Cervus elaphus scoticus, more successful males give sexually-selected calls (roars) with higher minimum F0s, suggesting that high, rather than low F0s advertise quality in this subspecies. While playback experiments demonstrated that oestrous females prefer higher pitched roars, the potential role of roar F0 in male competition remains untested. Here we examined the response of rutting red deer stags to playbacks of re-synthesized male roars with different median F0s. Our results show that stags’ responses (latencies and durations of attention, vocal and approach responses) were not affected by the F0 of the roar. This suggests that intrasexual selection is unlikely to strongly influence the evolution of roar F0 in Scottish red deer stags, and illustrates how the F0 of terrestrial mammal vocal sexual signals may be subject to different selection pressures across species. Further investigations on species characterized by different F0 profiles are needed to provide a comparative background for evolutionary interpretations of sex differences in mammalian vocalizations

Two distinct sequences of blue straggler stars in the globular cluster M30

Stars in globular clusters are generally believed to have all formed at the same time, early in the Galaxy's history. 'Blue stragglers' are stars massive enough that they should have evolved into white dwarfs long ago. Two possible mechanisms have been proposed for their formation: mass transfer between binary companions and stellar mergers resulting from direct collisions between two stars. Recently, the binary explanation was claimed to be dominant. Here we report that there are two distinct parallel sequences of blue stragglers in M30. This globular cluster is thought to have undergone 'core collapse', during which both the collision rate and the mass transfer activity in binary systems would have been enhanced. We suggest that the two observed sequences arise from the cluster core collapse, with the bluer population arising from direct stellar collisions and the redder one arising from the evolution of close binaries that are probably still experiencing an active phase of mass transfer.Comment: Published on the 24th December 2009 issue of Natur

Correction for Colón-González et al., Limiting global-mean temperature increase to 1.5-2 °C could reduce the incidence and spatial spread of dengue fever in Latin America.

Correction for “Limiting global-mean temperature increase to 1.5–2 °C could reduce the incidence and spatial spread of dengue fever in Latin America,” by Felipe J. Colón-González, Ian Harris, Timothy J. Osborn, Christine Steiner São Bernardo, Carlos A. Peres, Paul R. Hunter, and Iain R. Lake, which was first published May 29, 2018; 10.1073/pnas.1718945115 (Proc. Natl. Acad. Sci. U.S.A. 115, 6243–6248). The authors note that Rachel Warren and Detlef van Vuuren should be added to the author list. Rachel Warren should appear as the seventh author, following Paul R. Hunter. Detlef van Vuuren should appear as the eighth author, following Rachel Warren and preceding Iain R. Lake. Rachel Warren should be credited with designing research. Detlef van Vuuren should be credited with contributing data. The corrected author line, affiliation line, and author contributions appear below. The online version has been corrected. The authors also note that the following statement should be added to the Acknowledgments: “R.W. and D.v.V. also received funding from the United Kingdom government, Department for Business, Energy, and Industrial Strategy, as part of the ‘Implications of Global Warming of 1.5 °C and 2.0 °C Project.’