Supercooling as a Viable Non-Freezing Cell Preservation Method of Rat Hepatocytes

Supercooling preservation holds the potential to drastically extend the preservation time of organs, tissues and engineered tissue products, and fragile cell types that do not lend themselves well to cryopreservation or vitrification. Here, we investigate the effects of supercooling preservation (SCP at -4oC) on primary rat hepatocytes stored in cryovials and compare its success (high viability and good functional characteristics) to that of static cold storage (CS at +4oC) and cryopreservation. We consider two prominent preservation solutions a) Hypothermosol (HTS-FRS) and b) University of Wisconsin solution (UW) and a range of preservation temperatures (-4 to -10 oC). We find that there exists an optimum temperature (-4oC) for SCP of rat hepatocytes which yields the highest viability; at this temperature HTS-FRS significantly outperforms UW solution in terms of viability and functional characteristics (secretions and enzymatic activity in suspension and plate culture). With the HTS-FRS solution we show that the cells can be stored for up to a week with high viability (~56%); moreover we also show that the preservation can be performed in large batches (50 million cells) with equal or better viability and no loss of functionality as compared to smaller batches (1.5 million cells) performed in cryovials

Split-Liver Ex Situ Machine Perfusion:A Novel Technique for Studying Organ Preservation and Therapeutic Interventions

Ex situ machine perfusion is a promising technology to help improve organ viability prior to transplantation. However, preclinical studies using discarded human livers to evaluate therapeutic interventions and optimize perfusion conditions are limited by significant graft heterogeneity. In order to improve the efficacy and reproducibility of future studies, a split-liver perfusion model was developed to allow simultaneous perfusion of left and right lobes, allowing one lobe to serve as a control for the other. Eleven discarded livers were surgically split, and both lobes perfused simultaneously on separate perfusion devices for 3 h at subnormothermic temperatures. Lobar perfusion parameters were also compared with whole livers undergoing perfusion. Similar to whole-liver perfusions, each lobe in the split-liver model exhibited a progressive decrease in arterial resistance and lactate levels throughout perfusion, which were not significantly different between right and left lobes. Split liver lobes also demonstrated comparable energy charge ratios. Ex situ split-liver perfusion is a novel experimental model that allows each graft to act as its own control. This model is particularly well suited for preclinical studies by avoiding the need for large numbers of enrolled livers necessary due to the heterogenous nature of discarded human liver research

Evaluation comparative de deux techniques d'empreintes en prothèse fixée au Centre de Soins et de Recherches Dentaires (CSERD) de Clermont-Ferrand (double mélange et wash-technique)

CLERMONT FD-BCIU Odontol. (631132226) / SudocCLERMONT FD-BCIU-Santé (631132104) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Surgeon's view on the limitations of left-handedness during endoscopic surgery

WOS: 000255182700008PubMed ID: 18373447Background: The influence of endoscopic surgery on left-handedness is unclear. The aim of this study was to investigate the role of left-handedness during endoscopic surgery. Materials and Methods: A survey distributed during the 15th Congress of the Turkish Society of Surgery, held in 2006, was conducted to 194 participants. The survey was focused on hand preference and endoscopic surgery. Besides demographic data and use of endoscopy, lateral predominance, questions related to surgical performance (open and endoscopic), training support during residency, and operating room experiences during endoscopic surgery were assessed. Results: The laterality preference in performing surgery was left in 9.3% (n = 18). Almost 50% of the left-handed surgeons believed that endoscopic surgery needs to be modified for the left-handed endoscopic surgeon, although 66% reported they had no difficulty while using endoscopic instruments and did not need any modification during surgical endoscopy. Over 86% of all surgeons reported that laterality had no importance for them if they were a patient undergoing endoscopic surgery, while 14% of surgeons refused to be operated on by a left-handed surgeon. Conclusion: Endoscopic surgery has impact on laterality-related comfort, and technical modifications are warranted for left-handed surgeons. Further research is needed to address questions related to hand dominance in surgical endoscopic skill performance that allows more comprehensive conclusions

Improving the quality of operation notes: Effect of using proforma, audit and education sessions

WOS: 000544899000006PubMed: 31653554Background: Both from a medical and legal point of view, the quality of operative notes are important. in this study we hypothesized that the quality of operation notes could be improved by audit, education session and using a proforma. Methods: A total of 150 operation notes were audited for compliance with the Royal College of Surgeons guidelines. Results were announced in -clinic training session and guidelines were dis- cussed. An aide-memoire containing guideline parameters placed in the operating theaters. After eight months, operation reports were re -audited on an equal number of patients. An operative note proforma was developed and third audit was carried out. the results of each audit were compared. Results: in the first audit, it was found that fourteen parameters were written with more than 90% accuracy. the first audit revealed seven poor areas in documentation: time of operation (0%), identification of emergency/elective procedure (0%), identification of any prosthesis or devices used (65.3%), details of closure technique (36.6%), name of anesthesiologist (0%), pa- tient position (1.3%), and amount of bleeding (0%). in the second audit there was an incom- plete, but significant improvement in these seven parameters (28%, 28.6%, 82%, 75.3%, 31.3%, 32%, and 34% respectively). Following introduction of the proforma; third audit cycle demonstrated a clear improvement in operation note documentation with at least 80% compli- ance in all parameters. Conclusion: This study revealed that the accuracy of the operating room documents can be improved through audits, education of surgeon and using proformas. the use of proforma pro- vides much better results. (C) 2019 Asian Surgical Association and Taiwan Robotic Surgery Association. Publishing services by Elsevier B. V. This is an open access article under the CC BY-NC- ND license (http:// creativecommons.org/licenses/by-nc-nd/4.0/)

Pattern recognition for subfamily level classification of GPCRs using motif distillation and distinguishing power evaluation

G protein coupled receptors (GPCRs) are one of the most prominent and abundant family of membrane proteins in the human genome. Since they are main targets of many drugs, GPCR research has grown significantly in recent years. However the fact that only few structures of GPCRs are known still remains as an important challenge. Therefore, the classification of GPCRs is a significant problem provoked from increasing gap between orphan GPCR sequences and a small amount of annotated ones. This work employs motif distillation using defined parameters, distinguishing power evaluation method and general weighted set cover problem in order to determine the minimum set of motifs which can cover a particular GPCR subfamily. Our results indicate that in Family A Peptide subfamily, 91% of all proteins listed in GPCRdb can be covered by using only 691 different motifs, which can be employed later as an invaluable source for developing a third level GPCR classification tool

Evidence for an association of serum melatonin concentrations with recognition and circadian preferences in patients with schizophrenia

Melatonin, a neuro-differentiation factor, may play a role in the neurodevelopmental origins of schizophrenia. Cognitive impairment and decreased melatonin are reported in schizophrenia; however, the relationship between them remains unclear. We hypothesised that patients with schizophrenia would have lower concentrations of circulating melatonin than healthy controls and that melatonin levels would be associated with cognitive impairment. This study included 47 patients with schizophrenia and 40 healthy controls (HC). Serum melatonin concentrations were measured using the enzyme-linked immunosorbent assay. Positive and Negative Syndrome Scales (PANSS), The Morningness-Eveningness Questionnaire (MEQ), Pittsburgh Sleep Quality Index (PSQI), the Stroop and Oktem verbal memory processes (VMPT) tests were applied. Patients with schizophrenia had lower levels of melatonin compared to the HC group (p=0.016), also after controlling for age, sex, and body mass index (BMI) (p=0.024). In patients with schizophrenia, melatonin concentrations were associated with higher BMI (rho=0.34, p=0.01) and lower MEQ score (rho=-0.29, p=0.035). The patient sample was split into low and high melatonin categories by using the median melatonin concentration in HC as the cut-off. Patients in the low melatonin group had poorer performance in VMPT-Recognition (p=0.026) and Stroop-Colour Error (p=0.032). Notwithstanding its limitations, the findings of this exploratory study suggest that decreased serum melatonin concentrations observed in schizophrenia might also be associated with cognitive impairment and circadian preferences. Future studies are required to investigate the role of melatonergic pathways in patients with schizophrenia