Potential of biocompatible regenerated silk fibroin/sodium N-lauroyl sarcosinate hydrogels

Hydrogels are becoming widely used in biomaterial applications. The available methods for the preparation of these materials are continually growing. The gelation time (GT) of silk protein fibroin is difficult to control by physical methods. The cross-linkers used in available chemical techniques are likely to impact the biocompatibility of the resultant materials. In this paper, we demonstrate that the addition of sodium N-lauroyl sarcosinate (an amino-acid-based surfactant) accelerates the formation of hydrogels from fibroin. GT, turbidity variations, changes of viscoelasticity during the gelation process, and the mechanical properties of the products are measured. The secondary structure was probed by Fourier transform infrared spectroscopy, X-ray diffraction and the morphologies of the products were investigated by scanning electron microscopy. Transformations in the β-sheet content were monitored by the fluorescence of Thioflavine T and circular dichroism measurements. The relationship between the surface tension of sodium N-lauroyl sarcosinate and the GT was also explained. To investigate cell compatibility, fibroblast cells were seeded onto the surface of the hydrogels. The results indicate that the sodium N-lauroyl sarcosinate/fibroin GT can be controlled. This blend-hydrogel demonstrates excellent cell compatibility, good compression strength, and outstanding compression-recovery characteristics. Sodium N-lauroyl sarcosinate/silk fibroin hydrogels containing β-sheets have considerable potential as replacement materials in addressing the tissue defects involved with repair surgery.     

A Study of Promethazine Hydrochloride and Pentazocine Intramuscular Sedation Along with 2?% Lidocaine Hydrochloride and Adrenaline and Comparison to Placebo Along with 2?% Lidocaine Hydrochloride and Adrenaline for Surgical Extraction of Mandibular Third Molar

Background and Objectives

The main objective is to study and compare the sedative and analgesic effects of intramuscular injection fortwin–phenergan along with local anesthetic and normal saline placebo along with local anesthetics in mandibular third molar surgery. We also assessed and compared the postoperative experience of the patient in relation to the pain intensity, time to first analgesic taken and total number of analgesics consumed over a period of 48 h in the two groups.

Materials and Methods

Patients who came to the Department of Oral and Maxillofacial Surgery, The Regional Dental College; with complaints regarding mandibular third molar were chosen for the treatment. Patients were evaluated using Corah Dental Anxiety Scale (CDAS) and those patients having a score of CDAS 13 and above were selected. Sixty patients were selected out of which 30 patients formed group 1 and another 30 patients group 2. The patients were randomly divided with flip method into group 1 (study group) and or group 2 (controlled group).

Results

Our study results showed that the operating conditions for both the groups at the end of surgery were similar without significant difference. Most of the surgical procedures were graded as excellent and good in both the groups except that difficulty was encountered in two patients from group 1 and one from group 2.

Conclusion

It could be concluded that particular drugs do not have much influence on the surgical procedure in our study, but it was found that patients from group 1 were more cooperative as compared to group 2 when difficulty was encountered during the surgical procedure.     

Incidental biliary dilation in the era of the opiate epidemic: High prevalence of biliary dilation in opiate users evaluated in the Emergency Department

BACKGROUNDBiliary dilation is frequently related to obstruction; however, non-obstructive factors such as age and previous cholecystectomy have also been reported. In the past two decades there has been a dramatic increase in opiate use/dependence and utilization of cross-sectional abdominal imaging, with increased detection of biliary dilation, particularly in patients who use opiates.AIMTo evaluate associations between opiate use, age, cholecystectomy status, ethnicity, gender, and body mass index utilizing our institution’s integrated informatics platform. METHODSOne thousand six hundred and eighty-five patients (20% sample) presenting to our Emergency Department for all causes over a 5-year period (2011-2016) who had undergone cross-sectional abdominal imaging and had normal total bilirubin were included and analyzed.RESULTSCommon bile duct (CBD) diameter was significantly higher in opiate users compared to non-opiate users (8.67 mm vs 7.24 mm, P < 0.001) and in patients with a history of cholecystectomy compared to those with an intact gallbladder (8.98 vs 6.72, P < 0.001). For patients with an intact gallbladder who did not use opiates (n = 432), increasing age did not predict CBD diameter (r² = 0.159, P = 0.873). Height weakly predicted CBD diameter (r² = 0.561, P = 0.018), but weight, body mass index, ethnicity and gender did not.CONCLUSIONOpiate use and a history of cholecystectomy are associated with CBD dilation in the absence of an obstructive process. Age alone is not associated with increased CBD diameter. These findings suggest that factors such as opiate use and history of cholecystectomy may underlie the previously-reported association of advancing age with increased CBD diameter. Further prospective study is warranted.     

Hyponatremia in critically ill patients

Context:

Hyponatremia is a common electrolyte disturbance in critically ill hence understanding its implications is important.

Aims:

This study was carried out to ascertain frequency, predisposing conditions and outcome in critically ill patients with hyponatremia on intensive care unit (ICU) admission.

Settings and Design:

This was an observational, prospective study of a series of ICU patients during a 12-month period.

Materials and Methods:

The patients were divided into two groups: Hyponatremic (serum sodium < 135 mmol/L) and Eunatremic groups (135-145 mmol/L). Clinical examination included volume status and drug history, biochemistries, clinical diagnosis and cause of hyponatremia.

Statistical Analysis Used:

Fisher''s exact test, unpaired t-tests Wilcoxon ranksum tests, profile-likelihood method, log-rank test and Kaplan—Meier curves were used. P < 0.05 were considered to be statistically significant.

Results:

In the hyponatremic group, the frequency of hyponatremia on ICU admission was 34.3%, most were euvolumic, 58.96%. Females comprised of 36.5%. The mean age was 60.4 ± 17.2. The Syndrome of inappropriate Antidiuretic Hormone (SIADH) criteria was met in ninety-one patients (36.25%), peumonia being the leading cause of SIADH. Patients with severe sepsis, elective surgery patients, renal failure and heart failure, cirrhosis of liver and subarachnoid hemorrhage were other more likely etiologic causes (P < 0.05). The hyponatremic group spent a longer time in the ICU (P = 0.02), had longer mechanical ventilator days (P < 0.05) and had an increased mortality rate (P = 0.01).

Conclusions:

Hyponatremia present on admission to the ICU is independent risk factors for poor prognosis.     

Mussel inspired ZIF8 microcarriers: a new approach for large-scale production of stem cells

Metal–organic frameworks (MOFs) have high porosity, large surface area, and tunable functionality and have been widely used for drug loading. The aim of this study was to exploit unique features of zeolitic imidazolate framework-8 (ZIF8) to develop an innovative composite microcarrier (MC) for human mesenchymal stem cells (hMSCs) adhesion and proliferation. ZIF8 MCs were prepared by immobilization of polydopamine/polyethyleneimine (PDA/PEI) and ZIF8 on the surface of polystyrene beads. The chemical properties of MCs such as coating stability and homogeneity were characterized by different techniques such as ATR-FTIR, XRD, EDX, SEM, and contact angle. The prepared MCs were tested using human adipose-derived mesenchymal stem cells (hADSCs) in both static and dynamic conditions, and results were compared to a commercially available MC (Star-Plus), polydopamine coated MCs and amine-functionalized MCs as a control. Results show that PDA/PEI/ZIF8 coated MCs (in short: ZIF8 MCs) provides an excellent biocompatible environment for hADSCs adhesion and growth. In conclusion, ZIF8 MCs represent suitable and low-cost support for hADSCs culture and expansion, which can maximize cell yield and viability while preserving hADSCs multipotency. The present findings have revealed this strategy has the potential for chemical and topographical modification of MCs in tissue engineering applications.

Mussel inspired ZIF8 microcarriers with high surface area, biocompatibility, and nanoscale surface roughness are applied to enhance mesenchymal stem cell attachment and proliferation in 3D cell culture.