Experimental evaluation of an artificial anal sphincter based on biomechanical compatibility.

BACKGROUND: The artificial anal sphincter is a device used to treat patients with fecal incontinence who are unable to control their bowel movements on their own. Long-term morphological changes in the tissue surrounding the artificial anal sphincter can cause biomechanical compatibility problems, which seriously affect the clinical application of the artificial anal sphincter. METHODS: In this paper, the superelasticity of shape memory alloys was utilized to design and fabricate a biomechanically compatible constant force clamping artificial anal sphincter. An in vitro simulation system was constructed to verify the effectiveness, safety, and constant force characteristics of the artificial anal sphincter. RESULTS: The experimental results demonstrated that the artificial anal sphincter could be effectively closed with no leakage of the liquid-like intestinal contents, which are most likely to leak. The pressure of the artificial anal sphincter on the intestinal tube gradually increased and eventually became constant during closure, and the pressure value was always less than the intestinal blood supply pressure threshold. CONCLUSIONS: In this paper, we designed an artificial anal sphincter based on biomechanical compatibility and the corresponding in vitro simulation experimental program and preliminarily verified the effectiveness, safety, and constant force characteristics of the artificial anal sphincter.

Features of Cytokine and VEGFA Gene Expression Modified with SARS-CoV-2 Virus in an In Vitro Experiment (Using the Example of the SARS-CoV-2 Vaccine Antigen).

The influence of SARS-CoV-2 antigen on the cytokine-producing function of immune cells was studied. We observed suppression of the production of proinflammatory cytokines by 11-46% relative to the spontaneous level under the influence of SARS-CoV-2 antigen vaccine simulator, as well as when it was co-administered with cortisol (IL-6 by 1.8 times and IFNγ by 1.57 times) compared with control samples. IL-8 production was reduced by 1.72 times relative to its spontaneous level. IL-8 production was reduced by 1.72 times relative to its spontaneous level. Under conditions of SARS-CoV-2 stimulation with the vaccine antigen in vitro, an increase in the relative scaled expression of the VEGFA gene by 2.16 times relative to the spontaneous level was observed, which can be regarded as a model "cytokine storm" scenario. The obtained experimental data verify the ideas about the pathogenetic mechanisms of the COVID-19 and can contribute to the development of new approaches to the correction of its complications.

Validation of quercetin in the treatment of colon cancer with diabetes via network pharmacology, molecular dynamics simulations, and in vitro experiments.

This study built a prognostic model for CRC-diabetes and analyzed whether quercetin could be used for CRC-diabetes treatment through a network of pharmacology, molecular dynamics simulation, bioinformatics, and in vitro experiments. First, multivariate Cox proportional hazards regression was used to construct the prognosis modelof CRC-diabetes. Then, the intersection of quercetin target genes with CRC-diabetes genes was used to find the potential target for quercetin in the treatment of CRC-diabetes. Molecular docking and molecular dynamics simulations were used to screen the potential targets for quercetin in the treatment of CRC-diabetes. Finally, we verified the target and pathway of quercetin in the treatment of CRC-diabetes through in vitro experiments. Through molecular docking, seven proteins (HMOX1, ACE, MYC, MMP9, PLAU, MMP3, and MMP1) were selected as potential targets of quercetin. We conducted molecular dynamics simulations of quercetin and the above proteins, respectively, and found that the binding structure of quercetin with MMP9 and PLAU was relatively stable. Finally, according to the results of Western blot results, it was confirmed that quercetin could interact with MMP9. The experimental results show that quercetin may affect the JNK pathway, glycolysis, and epithelial-mesenchymal transition (EMT) to treat CRC-diabetes. Based on the TCGA, TTD, DrugBank, and other databases, a prediction model that can effectively predict the prognosis of colon cancer patients with diabetes was constructed. According to experiment results, quercetin can regulate the expression of MMP9. By acting on the JNK pathway, glycolysis, and EMT, it can treat colon cancer patients with diabetes.

Biomechanical Evaluation of an Adaptive-Motion Pedicle Screw Fixation System: Experimental and Numerical Analysis.

Rigid fixation is mostly used in thoracolumbar spine surgery, which restricts the thoracolumbar spine segments moving and is not conducive to postoperative rehabilitation. We developed an adaptive-motion pedicle screw and established a finite element model of the T12-L3 segments of the thoracolumbar spine in osteoporosis patients based on the CT image data. A variety of internal fixation finite element models were established for mechanical simulation analysis and comparison. The simulation results showed that compared with the conventional internal fixation system, the mobility of the new adaptive-motion internal fixation system was improved by about 13.8% and 7.7% under the classic conditions such as lateral bending and flexion. in vitro experiments were conducted simultaneously with fresh porcine thoracolumbar spine vertebrae, and the axial rotation condition was taken as an example to analyze the mobility. The in vitro results showed that the mobility of the adaptive-motion internal fixation system had better mobility characteristics under axial rotation conditions, which was consistent with the finite element analysis. The adaptive-motion pedicle screws can preserve a certain degree of vertebral mobility, and avoid excessive vertebral restriction. It also increases the stress value of the intervertebral disk, which is closer to the normal mechanical transmission of the human body, avoiding stress masking and slowing down the degeneration of the intervertebral disk. The adaptive-motion pedicle screws can reduce the peak stress of the implant and avoid surgical failure due to implant fracture.

[Mechanism of Xuebijing Injection in treatment of sepsis-associated ARDS based on network pharmacology and in vitro experiment].

The aim of this study was to investigate the effect and molecular mechanism of Xuebijing Injection in the treatment of sepsis-associated acute respiratory distress syndrome(ARDS) based on network pharmacology and in vitro experiment. The active components of Xuebijing Injection were screened and the targets were predicted by the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform(TCMSP). The targets of sepsis-associated ARDS were searched against GeneCards, DisGeNet, OMIM, and TTD. Weishengxin platform was used to map the targets of the main active components in Xuebijing Injection and the targets of sepsis-associated ARDS, and Venn diagram was established to identify the common targets. Cytoscape 3.9.1 was used to build the "drug-active components-common targets-disease" network. The common targets were imported into STRING for the building of the protein-protein interaction(PPI) network, which was then imported into Cytoscape 3.9.1 for visualization. DAVID 6.8 was used for Gene Ontology(GO) and Kyoto Encyclopedia of Genes and Genomes(KEGG) enrichment of the common targets, and then Weishe-ngxin platform was used for visualization of the enrichment results. The top 20 KEGG signaling pathways were selected and imported into Cytoscape 3.9.1 to establish the KEGG network. Finally, molecular docking and in vitro cell experiment were performed to verify the prediction results. A total of 115 active components and 217 targets of Xuebijing Injection and 360 targets of sepsis-associated ARDS were obtained, among which 63 common targets were shared by Xuebijing Injection and the disease. The core targets included interleukin-1 beta(IL-1ß), IL-6, albumin(ALB), serine/threonine-protein kinase(AKT1), and vascular endothelial growth factor A(VEGFA). A total of 453 GO terms were annotated, including 361 terms of biological processes(BP), 33 terms of cellular components(CC), and 59 terms of molecular functions(MF). The terms mainly involved cellular response to lipopolysaccharide, negative regulation of apoptotic process, lipopolysaccharide-mediated signaling pathway, positive regulation of transcription from RNA polyme-rase Ⅱ promoter, response to hypoxia, and inflammatory response. The KEGG enrichment revealed 85 pathways. After diseases and generalized pathways were eliminated, hypoxia-inducible factor-1(HIF-1), tumor necrosis factor(TNF), nuclear factor-kappa B(NF-κB), Toll-like receptor, and NOD-like receptor signaling pathways were screened out. Molecular docking showed that the main active components of Xuebijing Injection had good binding activity with the core targets. The in vitro experiment confirmed that Xuebijing Injection suppressed the HIF-1, TNF, NF-κB, Toll-like receptor, and NOD-like receptor signaling pathways, inhibited cell apoptosis and reactive oxygen species generation, and down-regulated the expression of TNF-α, IL-1ß, and IL-6 in cells. In conclusion, Xuebijing Injection can regulate apoptosis and response to inflammation and oxidative stress by acting on HIF-1, TNF, NF-κB, Toll-like receptor, and NOD-like receptor signaling pathways to treat sepsis-associated ARDS.

Catheter contact angle influences local impedance drop during radiofrequency catheter ablation: Insight from a porcine experimental study with 2 different LI-sensing catheters.

BACKGROUND: Local impedance (LI) can indirectly measure catheter contact and tissue temperature during radiofrequency catheter ablation (RFCA). However, data on the effects of catheter contact angle on LI parameters are scarce. This study aimed to evaluate the influence of catheter contact angle on LI changes and lesion size with two different LI-sensing catheters in a porcine experimental study. METHODS: Lesions were created by the INTELLANAV MiFi™ OI (MiFi) and the INTELLANAV STABLEPOINT™ (STABLEPOINT). RFCA was performed with 30 W and a duration of 30 s. The contact force (CF) (0, 5, 10, 20, and 30 g) and catheter contact angle (30°, 45°, and 90°) were changed in each set (n = 8 each). The LI rise, LI drop, and lesion size were evaluated. RESULTS: The LI rise increased as CF increased. There was no angular dependence with the LI rise under all CFs in the MiFi. On the other hand, the LI rise at 90° was lower than at 30° under 5 and 10 g of CF in STABLEPOINT. The LI drop increased as CF increased. Regarding the difference in catheter contact angles, the LI drop at 90° was lower than that at 30° for both catheters. The maximum lesion widths and surface widths were smaller at 90° than at 30°, whereas there were no differences in lesion depths. CONCLUSION: The LI drop and lesion widths at 90° were significantly smaller than those at 30°, although the lesion depths were not different among the 3 angles for the MiFi and STABLEPOINT.

Drainage of infected kidneys with ureteral stents: does size matter?

PURPOSE: The purpose of our study was to evaluate the ability of ureteral stents with different diameters to drain pus that accumulates in an obstructed kidney using an in vitro model. METHODS: We developed an in vitro model of an obstructed kidney filled with pus. The model included a silicon kidney unit based on computed tomography (CT) data, a 3D printed ureteral stone based on a real extracted ureteral stone, a latex ureter model, a bladder vessel, and a fluid with qualities resembling pus. Identical printed stones were inserted into four ureter models containing stents with varying diameters (4.8F, 6F, 7F, 8F), each of which was connected to the kidney unit and the bladder vessel. The kidney unit was filled with artificial pus to pressures of 30 cmH2O to simulate an infected and obstructed kidney. The obstruction was relieved with stents in place, while artificial urine was pumped into the kidney; pressure in the kidney and remaining pus were measured continuously. RESULTS: The rate of pressure drop and the final pressure measured in the kidney were unaffected by the diameter of the stent. For all stent diameters, the pressure reached non-obstructed levels within 30 s, final pressure was reached within 90-120 s, and minimal amounts of pus remained in the kidney after 120 min. CONCLUSIONS: In vitro experiments demonstrate that all stent diameters drain pus-filled, obstructed kidneys with the same efficacy. The common perception that larger diameter tubes are more effective under such circumstances should be re-examined.

Thiazole/Thiadiazole/Benzothiazole Based Thiazolidin-4-One Derivatives as Potential Inhibitors of Main Protease of SARS-CoV-2.

Since the time of its appearance until present, COVID-19 has spread worldwide, with over 71 million confirmed cases and over 1.6 million deaths reported by the World Health Organization (WHO). In addition to the fact that cases of COVID-19 are increasing worldwide, the Delta and Omicron variants have also made the situation more challenging. Herein, we report the evaluation of several thiazole/thiadiazole/benzothiazole based thiazolidinone derivatives which were chosen from 112 designed derivatives by docking as potential molecules to inhibit the main protease of SARS-CoV-2. The contained experimental data revealed that among the fifteen compounds chosen, five compounds (k3, c1, n2, A2, A1) showed inhibitory activity with IC50 within the range of 0.01-34.4 µΜ. By assessing the cellular effects of these molecules, we observed that they also had the capacity to affect the cellular viability of human normal MRC-5 cells, albeit with a degree of variation. More specifically, k3 which is the most promising compound with the higher inhibitory capacity to SARS-CoV-2 protease (0.01 µΜ) affects in vitro cellular viability only by 57% at the concentration of 0.01 µM after 48 h in culture. Overall, these data provide evidence on the potential antiviral activity of these molecules to inhibit the main protease of SARS-CoV-2, a fact that sheds light on the chemical structure of the thiazole/thiadiazole/benzothiazole based thiazolidin-4-one derivatives as potential candidates for COVID-19 therapeutics.

[Activity of curcumin against human cytomegalovirus infection in vitro].

This study aimed to investigate the effect of curcumin (Cur) against human cytomegalovirus (HCMV) in vitro. Human embryonic lung fibroblasts were cultured in vitro. The tetrazolium salt (MTS) method was used to detect the effects of Cur on cell viability. The cells were divided into control group, HCMV group, HCMV + (PFA) group and HCMV + Cur group in this study. The cytopathic effect (CPE) of each group was observed by plaque test, then the copy number of HCMV DNA in each group was detected by quantitative polymerase chain reaction (qPCR), and the expression of HCMV proteins in different sequence was detected by Western blot. The results showed that when the concentration of Cur was not higher than 15 µmol/L, there was no significant change in cell growth and viability in the Cur group compared with the control group (P>0.05). After the cells were infected by HCMV for 5 d, the cells began to show CPE, and the number of plaques increased with time. Pretreatment with Cur significantly reduced CPE in a dose-dependent manner. After the cells were infected by HCMV, the DNA copy number and protein expression gradually increased in a time-dependent manner. Pretreatment with Cur significantly inhibited HCMV DNA copies and downregulate HCMV protein expression levels in a concentration-dependent manner, and the difference was statistically significant (P<0.05). In conclusion, Cur may exert anti-HCMV activity by inhibiting the replication of HCMV DNA and down-regulating the expression levels of different sequence proteins of HCMV. This study provides a new experimental basis for the development of anti-HCMV infectious drugs.

[Study on Impedance of Implantable Cardiac Pacemaker in Unipolar/Bipolar Pacing Mode by in Vitro Experiment].

The unipolar/bipolar pacing mode of pacemaker is related to its circuit impedance, which affects the battery life. In this study, the in vitro experiment scheme of pacemaker circuit impedance test was constructed. The human blood environment was simulated by NaCl solution, and the experimental environment temperature was controlled by water bath. The results of in vitro experiments showed that under the experimental conditions similar to clinical human parameters, the difference between the circuit impedance of bipolar mode and unipolar mode is 120~200 Ω. The results of the in vitro experiment confirmed that the circuit impedance of bipolar circuit was larger than that of unipolar mode, which was found in clinical practice. The results of this study have reference value to the optimization of pacing mode and the reduction of pacemaker power consumption.

Adaption of Lung Fibroblasts to Fluoro-Edenite Fibers: Evaluation of Molecular and Physiological Dynamics.

BACKGROUND/AIMS: The fluoro-edenite fibrous amphibole was identified as an environmental pollutant associate to risk of carcinogenicity. In Sicily (Italy), it represents a public health issue because fluoro-edenite fibers are present in the soil of Biancavilla, a town located on the south-west slopes of the volcano Etna. Since the relationship between exposure to fluoro-edenite and the onset of lung disorders have been documented, in vitro studies were performed to clarify the mechanisms of damage, but most aspects remain unknown. Here, we focus on the effects of mineral fibers in a primary culture of lung fibroblasts. We supposed that the cells react to fluoro-edenite exposure by establishing a process of adaption that could modify their metabolic activity, their proliferation, and their physiological functions, as the production of extracellular matrix (ECM) components. METHODS: To verify our hypothesis, we used immunofluorescence, cell proliferation, senescence, apoptosis, scratch, Western blot, Reverse transcription-polymerase chain reaction (RT-PCR), and evaluation of extracellular matrix components assays. RESULTS: Results demonstrated that lung fibroblasts react to fluoro-edenite by a down-regulation of mitochondrial activity, a reduction of cell growth and migration, and a resistance to apoptosis. These elements suggested the induction of a premature senescent phenotype that was confirmed by senescence-associated beta-galactosidase (SA-ß-Gal) activity, and by the analysis of ECM elements. We found an unbalance of collagens ratio, and changes in matrix metalloproteinase3 production and release. CONCLUSION: Our data suggest that fluoro-edenite-induced senescence of lung fibroblasts could be an early and underestimated step that may drive fibroblasts toward a fibrotic and carcinogenic phenotype.

The optimal ablation setting for a local impedance guided catheter in an in vitro experimental model.

BACKGROUND: The local impedance (LI) reflects the electrical catheter-tissue coupling and correlates with the local tissue temperature. However, there have been few clinical studies showing the recommended method for LI monitoring catheters. This study aimed to investigate the optimal ablation setting for this catheter in an in vitro experimental model. METHODS: LI monitoring catheters were used in an excised swine heart experimental model. The tissue contact force (CF) was directly monitored from an external weight scale. Radiofrequency ablation was performed with a combination of various energy power settings (30, 40, and 50 W), and various CFs (10, 30, and 50 g) for 60 s. The correlation between the LI-related indexes, power, and CF with the lesion formation was statistically analyzed. RESULTS: A positive correlation between the LI or lesion formation and CF was observed under all powers. Although the LI drop always correlated with the maximum lesion depth, lesion diameter, and lesion volume, the coefficient of the correlation value was lower under a high CF (lesion depth, diameter, and volume; 10 g, r = 0.8064, r = 0.8389, r = 0.8477; 30 g, r = 0.7590, r = 0.8063, r = 0.8060; 50 g r = 0.5555, r = 0.5701, and r = 0.5678, respectively). Steam pops occurred only under a 50 W ablation and the LI drop cutoff value for steam pops was 46 Ω. CONCLUSION: The same LI drop did not always lead to the same lesion size when the CF differed. Monitoring the LI and not exceeding 46 Ω would be useful for a safe ablation.

Experimental Analysis of the Quality of Needle-Assisted Fenestration in Aortic Stent-Grafts and the Differences Between Gradual and Rapid Balloon Dilation.

Purpose: To report the findings of an in vitro experiment to evaluate the quality of needle fenestrations dilated by different size balloons in various stent-grafts and to investigate the differences between gradual and rapid dilation. Materials and Methods: Fenestrations were made using an 18-G needle in 5 different polyester or expanded polytetrafluoroethylene (ePTFE) stent-grafts: Relay, Valiant, Hercules, TAG, and Ankura. Each stent-graft received 2 groups of fenestrations: one was followed by gradual sequential dilation (4-, 6-, 8-, and 10-mm balloons) and the other by rapid dilation (4- and 10-mm balloons). The pressure was increased to 10 atmospheres or until the balloon was fully inflated with no waist. Quantitative and qualitative evaluations, including fenestration diameter, area, shape, and margins were conducted using light microscopy and scanning electron microscopy. Results: Relay had the strongest resistance to dilation and Ankura the slightest. The maximum length and area of holes expanded as the balloon diameter increased. The fenestrations in polyester devices were mostly elliptical or slit-like, with limited tears but extensive fibers visible in the margin, while ePTFE stent-grafts showed larger fenestration areas with clearer margins. Ankura showed the best quality of fenestrations, which were always circular or square without fabric tears, while the holes in the TAG were square or elliptical but sometimes had a slit after large balloon dilation (≥6 mm). The Relay, Valiant, Hercules, and Ankura devices showed no difference in maximum diameter, fenestration area, or scores of shape and margin (p>0.05). Rapid dilation in the TAG increased the rate of uncontrolled fabric tear, resulting in a larger final diameter (12.90 vs 10.82 mm, p=0.047), smaller area (30.46 vs 41.09 mm2, p=0.028), worse shape (0.75 vs 1.20, p=0.268), and worse margin (0.40 vs 1.00, p=0.174). Though the decreased fenestration shape and margin scores did not reach statistical significance, the trend for decline was more obvious than with the other devices. Conclusion: Materials and structures of the stent-grafts determine the quality of fenestrations dilated by different size balloons. The use of sequential vs rapid balloon dilation is also crucial for fashioning high-quality fenestrations and should be selected judiciously.

Does the use of Dermojet affect the concentration of platelet-rich plasma? An in vitro experimental investigation.

Needle-free injection systems with high jet pressure have been used for seven decades for drug or vaccine administration via intradermal, subcutaneous, and intramuscular routes. These systems are used for the application of mesotherapy drugs in plastic surgery and dermatology. Platelet-rich plasma (PRP) tissue regeneration is applied intradermally by a needle for different indications, such as wound healing and scar revision. To prevent complaints such as pain, erythema, and ecchymosis by patients during this application, PRP was applied using Dermojet, a jet injector system with a spring-loaded system. In this study, after measuring the average platelet count in PRP preparations obtained from 18 volunteers, a 2.5 cc PRP shot into an empty tube was performed with Dermojet. The mean platelet count was measured in a homogenized tube. The same procedures were performed for platelet-poor plasma (PPP). The platelet loss rates for PRP and PPP were compared. In addition, the amount of PRP in each shot of the Dermojet was calculated. When PRP and PPP were applied using the Dermojet, platelet loss was 8.41% and 8.33%, respectively. The difference in the number of platelets formed in PRP and PPP when applied with Dermojet was not statistically significant. PRP application with needle-free injection systems, such as Dermojet, may be an alternative because of patient comfort and the negligible platelet loss compared with the PRP application with the standard needle injection.

Can cavity-based pedicle screw augmentation decrease screw loosening? A biomechanical in vitro study.

PURPOSE: In an osteoporotic vertebral body, cement-augmented pedicle screw fixation could possibly be optimized by the creation of an initial cavity. The aim of this study is to compare three test groups with regard to their loosening characteristics under cyclic loading. METHODS: Eighteen human, osteoporotic spine segments were divided in three groups. Flexibility tests and cyclic loading tests were performed with an internal fixator. The screws were fixed after creation a cavity and with cement (cavity-augmented group), without cavity and with cement (augmented group), and without cavity and without cement (control group). Cyclic loading up to 100,000 cycles was applied with a complex loading protocol. Screw loosening was measured with flexibility tests after implantation and after cyclic loading. Cement distribution was visualized from CT scans. RESULTS: In all groups, range of motion increased during cyclic loading, representing significant screw loosening after 100,000 cycles. In both augmented groups, screw loosening was less pronounced than in the control group. The cavity-augmented group showed only a slight tendency of screw loosening, but with smaller variations compared to both other groups. This may be explained with a trend for a more equal and homogeneous cement volume around each tip for the cavity-augmented group. CONCLUSION: This study demonstrated that creating a cavity may allow a more equal fixation of all pedicle screws with slight reduction of loosening. However, augmentation only through a cannulated screw is almost equivalent, if care is taken that enough cement volume can be pushed out around the tip of the screw.

Laparoscopic specimen extraction in vitro: preliminary experience.

BACKGROUND: The last procedure performed by the surgeon in laparoscopic surgery is to extract the specimen through the smallest incision possible. This experiment aimed to explore the maximum diameter of specimens that can be extracted through auxiliary incisions of different lengths and shapes by in vitro physical experiments. MATERIALS AND METHODS: We used the abdominal wall with the muscle layer, fixed on a square wooden frame, to simulate the human abdominal wall. Then, specimen extraction ports were made with circular, inverted Y-shaped and straight-line incisions of different sizes and lengths, and specimens of different sizes were made from tissues of different species. These specimens were extracted from different incisions with a force gauge. The tension value (N) was measured, and records were made of the length or diameter of the smallest auxiliary incision through which a given specimen could pass, as well as the largest specimen diameter that could pass through an incision of a given size. This experiment provides us with preliminary experience-based knowledge of how to choose the appropriate auxiliary incision for surgical specimen extraction according to the diameter of the specimen. RESULTS: The maximum diameters of specimens that could be extracted with circular ostomy diameters of 2.4, 2.7 and 3.3 cm were 4.0, 4.5 and 6.0 cm, respectively. Specimens with diameters of 6.0, 8.0 and 10.0 cm could be extracted through inverted Y-shaped incisions with a length around the umbilicus of 1 cm and an extension length of 1.0, 3.0, and 4.0 cm, respectively. Moreover, these same specimens could be extracted through inverted Y-shaped incisions with a length around the umbilicus of 2 cm and extension lengths of 0.0, 1.0 and 2.0 cm. Tough tissue specimens (made from chicken gizzards) with diameters of 1.0, 2.0, 4.0 and 6.0 cm, respectively, could be removed through straight-line incisions measuring 1.0, 2.0, 3.0 and 4.0 cm in length. CONCLUSION: Along with preoperative imaging, surgical planning and trocar position, the shape and length of auxiliary incisions can be used to improve the extraction of specimens via laparoscopic surgery.

Characterization and whole-genome sequencing of broad-host-range Salmonella-specific bacteriophages for bio-control.

Salmonella Enteritidis (S. Enteritidis), which could cause human disease and death by consuming the contaminated food, is an important zoonotic pathogen. With the rapid increase of antibiotic resistance all over the world, bacteriophage-based bio-control has gradually attracted public attention widely. In order to find a suitable phage treating S. Enteritidis infection, four phages infecting S. Enteritidis were isolated from poultry fecal samples. Host range showed that four phages had a broad-host-range to Salmonella isolates. The morphological analysis illustrated that all of those phages were classified as the Myoviridae family. The one-step growth curve indicated that bacteriophage BPSELC-1 has a short latent period of about 10 min and a large burst size of 500 pfu/cell in comparison to the other three phages. Then phage BPSELC-1 was sequenced and conducted in vitro experiment. The genome of phage BPSELC-1 is 86,996 bp in size and has 140 putative genes containing structure proteins-encoding genes, tRNA genes and DNA replication or nucleotide metabolism genes. Importantly, no known virulence-associated, antibiotic and lysogeny-related genes were identified in the genome of BPSELC-1. In vitro experiment of phage treatment pointed out that the number of viable S. Enteritidis ATCC 13076 was reduced by 5.9×log10 at MOI of 102 after 4 h. To the best of our knowledge, the phage BPSELC-1 exhibited higher efficiency in S. Enteritidis treatment compared to previous studies. Moreover, it is promising to be used as a broad-spectrum candidate against Salmonella infections in commercial owing to its broad-host-range.

Comparison of the Biomechanical Properties of the Advanta V12/iCast and Viabahn Stent-Grafts as Bridging Devices in Fenestrated Endografts: An In Vitro Study.

Purpose: To compare experimentally the biomechanical properties of the Viabahn Balloon-Expandable Stent Graft (VBX) with the widely used Advanta V12/iCast in the role of bridging stent-grafts for fenestrated endovascular aortic repair. Materials and Methods: Test sheets made of polyester having 2 rows of 5 fenestrations in 6-mm and 8-mm diameters were used to simulate a commercially made fenestrated aortic endograft. In total, 40 stent-grafts measuring 6×39 mm and 8×39 mm (10 of each size for each stent-graft) were implanted in fenestration sheets immersed in a 37°C water bath. After flaring, all stent-grafts were evaluated using microscopy and radiography. Biomechanical evaluation included pullout and the shear stress force testing; results are reported in Newtons (N) as the median (minimum-maximum). Results: After flaring, no damage or fracture to the stent-graft structures were detected. Pullout forces for the 6-mm stent-grafts were 27.1 N (20.0-28.9) for the VBX and 16.6 N (14.7-19.2) for the Advanta (p=0.008). Pullout forces for the 8-mm stent-grafts were 20.1 N (14.8-21.5) for the VBX and 15.8 N (12.4-17.5) for the Advanta (p=0.095). The shear stress forces necessary to dislocate the device at 150% stent diameter displacement was 12.5 N (VBX) vs 14.7 N (Advanta) for the 6-mm devices and 23.3 N (VBX) vs 20.2 N (Advanta) for the 8-mm stents (p>0.99 and p=0.222, respectively). Conclusion: In vitro tests simulating external pull and shear forces on bridging stent-grafts implanted in fenestrations showed that the VBX had resistance to dislocation equivalent to a well-known control device.

Two novel ANK1 loss-of-function mutations in Chinese families with hereditary spherocytosis.

Hereditary spherocytosis (HS) is the most common inherited haemolytic anaemia disorder. ANK1 mutations account for most HS cases, but pathogenicity analysis and functional research have not been widely performed for these mutations. In this study, in order to confirm diagnosis, gene mutation was screened in two unrelated Chinese families with HS by a next-generation sequencing (NGS) panel and then confirmed by Sanger sequencing. Two novel heterozygous mutations (c.C841T, p.R281X and c.T290G, p.L97R) of the ANK1 gene were identified in the two families respectively. Then, the pathogenicity of the two new mutations and two previously reported ANK1 mutations (c.C648G, p.Y216X and c.G424T, p.E142X) were studied by in vitro experiments. The four mutations increased the osmotic fragility of cells, reduced the stabilities of ANK1 proteins and prevented the protein from localizing to the plasma membrane and interacting with SPTB and SLC4A1. We classified these four mutations into disease-causing mutations for HS. Thus, conducting the same mutation test and providing genetic counselling for the two families were meaningful and significant. Moreover, the identification of two novel mutations enriches the ANK1 mutation database, especially in China.

In Vitro Evaluation of the Gore Viabahn Balloon-Expandable Stent-Graft for Fenestrated Endovascular Aortic Repair.

PURPOSE: To evaluate the safety and integrity of a new stent-graft as a potential bridging device in fenestrated stent-grafts using an in vitro fenestrated model. MATERIALS AND METHODS: Polyester test sheets with ten 6-mm- or 8-mm-diameter fenestrations were used to simulate a fenestrated main body endoprosthesis. In total, 50 Viabahn balloon-expandable (VBX) stent-grafts of varying lengths (29 and 39 mm) and diameters (6, 7, and 8 mm) were implanted in the fitting fenestrations. After release, the 6- and 7-mm-diameter stent-grafts were flared with a 10×20-mm angioplasty balloon; a 12×20-mm balloon was used in the 8-mm-diameter devices. Safety of the devices was defined as absence of fractures detected on radiography or computed tomography (CT), as well as material failure detected by microscopy and water permeability testing. The forces (in Newtons, N) needed for perpendicular dislocation (pullout force) and axial dislocation (shear stress force) were also evaluated. RESULTS: Forty VBX stent-grafts were subjected to digital radiographic imaging and multiplanar CT. None showed any stent fracture. Subsequent microscopy indicated no damage to the fabric or separation of the graft after flaring. Ten VBX stent-grafts underwent water permeability testing after flaring; no water passed through the graft wall during a 10-minute period under an intraluminal pressure at 120 mm Hg. Testing of 25 VBX stent-grafts revealed initial pullout forces between 11.3 and 31 N. Shear stress tests showed that the average force needed to dislocate the stent-grafts by 50% of their diameter ranged between 5.75 and 6.91 N (mean 6.1±0.5 N) for the 6-mm stents and between 3.31 and 5.4 N (mean 4.4±0.8) for the 8-mm stents. CONCLUSION: This preliminary study demonstrated the applicability of the VBX as a bridging stent-graft in a simulated fenestration model. A comparison with other stent-grafts and clinical assessment are required.