Preterm pigs for preterm birth research: reasonably feasible

Preterm birth will disrupt the pattern and course of organ development, which may result in morbidity and mortality of newborn infants. Large animal models are crucial resources for developing novel, credible, and effective treatments for preterm infants. This review summarizes the classification, definition, and prevalence of preterm birth, and analyzes the relationship between the predicted animal days and one human year in the most widely used animal models (mice, rats, rabbits, sheep, and pigs) for preterm birth studies. After that, the physiological characteristics of preterm pig models at different gestational ages are described in more detail, including birth weight, body temperature, brain development, cardiovascular system development, respiratory, digestive, and immune system development, kidney development, and blood constituents. Studies on postnatal development and adaptation of preterm pig models of different gestational ages will help to determine the physiological basis for survival and development of very preterm, middle preterm, and late preterm newborns, and will also aid in the study and accurate optimization of feeding conditions, diet- or drug-related interventions for preterm neonates. Finally, this review summarizes several accepted pediatric applications of preterm pig models in nutritional fortification, necrotizing enterocolitis, neonatal encephalopathy and hypothermia intervention, mechanical ventilation, and oxygen therapy for preterm infants

Photoproduction of the charged top-pions at the LHeC

The top triangle moose $(TTM)$ model, which can be seen as the deconstructed version of the topcolor-assisted technicolor ($TC2$) model, predicts the existence of the charged top-pions $\pi_{t}^{\pm}$ in low energy spectrum. In the context of this model, we consider photoproduction of $\pi^{\pm}_{t}$ via the subprocesses $\gamma b\to t \pi_{t}^{-}$ and $\gamma \bar{b}\to \bar{t} \pi_{t}^{+}$ at the large hadron-electron collider ($LHeC$), in which high energy photon beams are generated by using the Compton backscatting method. We find that, as long as the charged top-pions are not too heavy, they can be abundantly produced via $\gamma b$ collision.Comment: 16 pages, 5 figure

A transferable heterogeneous two-hybrid system in Escherichia coli based on polyhydroxyalkanoates synthesis regulatory protein PhaR

<p>Abstract</p> <p>Background</p> <p>Polyhydroxyalkanoate (PHA) synthesis regulatory protein PhaR contains a DNA binding domain (DBD) and a PHA granule binding domain (GBD), it anchors to the promoter region of PHA granule-associated protein (PhaP) to repress <it>phaP </it>expression. However, PhaR will bind to PHB granules and be released from <it>phaP </it>promoter region when PHA granules are formed <it>in vivo</it>, initiating expression of <it>phaP </it>gene. Based on this regulatory mechanism, a bacterial two-hybrid system was developed: PhaR was separated into two parts: DBD was used to fuse with the bait, GBD with the prey, and <it>phaP </it>was replaced by a reporter gene <it>lacZ</it>. However, GBD protein expressed <it>in vivo </it>formed inclusion bodies. Thus, PhaP with strong binding ability to PHB granules was employed to replace GBD.</p> <p>Results</p> <p>Three model interaction partners bFos, bJun and bATF2 were used to study the feasibility of this bacterial two-hybrid system compared with the controls lacking one or more essential elements of this system. Results showed that bFos, bJun and bATF2 bound tightly in pairs to allow strong expression of β-galactosidase in different expression levels. In contrast, very weak β-galactosidase activity was detected in all control groups.</p> <p>Conclusion</p> <p>β-Galactosidase activity level precisely correlated with the interaction force of tested protein pairs, and very weak β-galactosidase expression was detected throughout the control groups, which demonstrated the feasibility of this system for studying protein interactions.</p

Theoretical Study of Seal Spring in a Wankel Compressor

The successful fabrication of a miniature Wankel compressor relies on its seal performance.The factors that influence the seal of a miniature Wankel compressor mainly include axial double mechanical seal and apex seals.Axial mechanical seal depends on machining precision on the end face.In the compression cavity, the springs for seal flake on the Wankel rotor put pressure on cylinder ,which generates the desired amount of pressing force.When springs fails,high-pressure cavity and low-pressure cavity will be connected.Spring performance will directly affect the efficiency of a Wankel compressor.In this paper,we aim to introduce kinematic analysis of apex seals and force analysis of springs in a miniature Wankel compressor

En bloc resection for treatment of refractory pre-auricular fistula

AbstractObjectiveTo report a surgical method for the treatment of pre-auricular fistula to lower post-operative recurrence rate.MethodsClinical data of 187 patients with pre-auricular fistula who underwent en bloc resection at the Affiliated Hospital of Luzhou Medical College from August 2006 to November 2012 were retrospectively reviewed. Factors that might affect the prognosis following En bloc fistula resection bordered by the superficial temporalis fascia, helix perichondrium and auriculocephalic sulcus were investigated.ResultsOf the 187 patients, 181 achieved primary healing and 6 ended up with delayed healing. During the follow-up period (one to seven years), there were 4 cases of recurrence (2.1%).ConclusionsClear demarcation of surgical resection can facilitate easy and thorough resection of preauricular fistula and lead to low recurrence rate. Proper timing and careful search for potential fistula branches are the two crucial factors affecting prognosis

Estimation of oil spray cooling heat transfer coefficients on hairpin windings with reduced-parameter models

Hairpin windings and spray cooling are becoming an increasingly popular combination in the field of high-performance electrical machine design. Machines adopting hairpin windings can achieve higher torque and power densities while enabling them to be manufactured automatically on a large scale to meet the rapid market growth of electric transport. Spray cooling is an effective way for high heat flux removal, which has shown great potentials in electrical machine applications. Although spray cooling has been studied for decades in different engineering applications, the focus had been on investigating its performance on regular surfaces using low-viscosity liquids, such as water. Additionally, many existing models for spray cooling heat transfer were built on spray parameters that are difficult to obtain without specialist equipment. Thus, most results from previous studies are difficult to be interpreted and directly applied to electrical machine applications. Practical and economical approaches for estimating the heat transfer coefficients of spray cooling on hairpin windings are needed. This paper proposes and validates an experimental approach based on reduced-parameter models which can be applied to predict the heat transfer coefficient of spray cooling setups on hairpin windings

Clinical experience exchange of 3 cases with Fournier’s gangrene

Fournier’s gangrene (FG), also known as necrotizing fasciitis, is a condition that affects the genitalia and perineum, resulting in the rapid development of necrosis and gangrene in infected tissues and potentially spreading to adjacent tissues, including the abdominal wall. It mainly affects males and requires prompt treatment to prevent potentially life-threatening complications. In Case 1, a 64-year-old man with type 2 diabetes was diagnosed with FG due to a scrotal skin injury after scratching his scrotal skin. The patient underwent radical debridement, treatment with broad-spectrum antibiotics, negative pressure wound treatment, and skin transplantation. In Case 2, a 79-year-old man suffered from a sebaceous cyst of the scrotum that had been scratched for seven days, resulting in black and necrotic skin of the scrotum. He was diagnosed with FG and underwent radical debridement and drainage of pus, followed by anti-infection treatment, negative pressure wound treatment, and skin transplantation. In Case 3, a 48-year-old male injured at the scrotum’s base developed swelling, pain, foul odor and pus discharge and was diagnosed with FG. The patient underwent emergency treatment, including incision and drainage of the scrotum and right lower abdominal wall abscess, as well as wound debridement. Ultimately, all three patients’ scrotal wounds returned to normal, but Case 2 was complicated by blood vessel thrombosis in both lower limbs. Early surgical debridement is a necessary intervention for FG, along with active postoperative anti-infection treatment and measures to prevent the occurrence of complications

In situ Proteomic Profiling of Curcumin Targets in HCT116 Colon Cancer Cell Line

To date, the exact targets and mechanism of action of curcumin, a natural product with anti-inflammatory and anti-cancer properties, remain elusive. Here we synthesized a cell permeable curcumin probe (Cur-P) with an alkyne moiety, which can be tagged with biotin for affinity enrichment, or with a fluorescent dye for visualization of the direct-binding protein targets of curcumin in situ. iTRAQ™ quantitative proteomics approach was applied to distinguish the specific binding targets from the non-specific ones. In total, 197 proteins were confidently identified as curcumin binding targets from HCT116 colon cancer cell line. Gene Ontology analysis showed that the targets are broadly distributed and enriched in the nucleus, mitochondria and plasma membrane, and they are involved in various biological functions including metabolic process, regulation, response to stimulus and cellular process. Ingenuity Pathway Analysis™ (IPA) suggested that curcumin may exert its anticancer effects over multiple critical biological pathways including the EIF2, eIF4/p70S6K, mTOR signaling and mitochondrial dysfunction pathways. Functional validations confirmed that curcumin downregulates cellular protein synthesis, and induces autophagy, lysosomal activation and increased ROS production, thus leading to cell death