[Feasibility reaserch on using Raman spectroscopy with PLS for the quantitative detection of cholesterol content in serum].

Taking the serum obtained from daily clinical inspection as study object, the Raman spectra were collected with the range of 250 to 2 400 cm(-1). Taking the serum cholesterol content determined by traditional clinical biochemical method as contrast, together with combination of PLS, we established a Raman spectroscopy quantitative models for cholesterol content in serum. The experimental results show that Raman spectroscopy displacement could reflect certain chemical group in organic compound. The correction model of cholesterol content in serum was established with the coefficient R = 0.909 6, cross-validation calibration standard deviation (RMSECV) of 0. 24, standard error of prediction of test set (RMSEP) was 0.69, and coefficient (R) is 0.926 2. The results showed that application of Raman spectroscopy combined with chemometrics in the rapid noninvasive detection of serum cholesterol content is feasible.

Hyponatremic encephalopathy due to polyethylene glycol-based bowel preparation for colonoscopy: A case report.

BACKGROUND: Adequate bowel preparation is critical for colonoscopy screening. At present, the most widely used intestinal cleaner recommended at home and abroad is Polyethylene glycol (PEG). Intestinal cleansers can cause electrolyte disturbances and hyponatremia. However, hyponatremic encephalopathy due to hyponatremia induced by PEG solution, although rare, can lead to serious irreversible sequelae and even death. CASE SUMMARY: In this report, we discuss a case of neurological dysfunction due to hyponatremia, also known as hyponatremic encephalopathy, observed in a 63-year-old woman who underwent PEG-based bowel preparation for colonoscopy. She was eventually transferred to our intensive care unit for treatment due to her Glasgow Coma Scale score of 9/15 (Eye opening 2; Verbal response 1; Motor response 6) and abnormal laboratory tests. CONCLUSION: Physicians should be thoroughly familiarized with the patient's history before prescribing PEG for bowel preparation, and timely identification of patients with hyponatremic encephalopathy is essential as delayed treatment is associated with poor neurological outcomes. An intravenous infusion of 3% sodium chloride is recommended at the onset of early symptoms. The goal of treatment is to adequately treat cerebral edema while avoiding serum sodium correction beyond 15 to 20 mEq/L within 48 h of treatment to prevent osmotic demyelination syndrome.

Fecal Bile Acids Profile of Crewmembers Consuming the Same Space Food in a Spacecraft Simulator.

Introduction: Recently, bile acids (BAs) are increasingly being considered as unique metabolic integrators and not just for the cholesterol metabolism and absorption of dietary lipids. Human BAs profiles are evolved to be individual under different environmental, dietary, and inherited factors. Variation of BAs for crewmembers from freshly prepared kitchen diets to wholly prepackaged industrial foods in a ground-based spacecraft simulator has not been clearly interpreted. Methods: Three crewmembers were confined in a docked spacecraft and supplied with 7 days periodic wholly prepackaged industrial foods for 50 days. Fecal samples were collected before entry in the spacecraft simulator and after evacuation. Determination of 16 kinds of BAs was carried out by high-performance liquid chromatography tandem mass spectrometry method. Results: Bile acids metabolism is sensitive to diet and environment transition from freshly prepared kitchen diets in the canteen to wholly prepackaged industrial foods in a ground-based spacecraft simulator, which is also specific to individuals. A significant positive relationship with a coefficient of 0.85 was found for primary BAs as chenodeoxycholic acid (CDCA) and cholic acid (CA), and a significantly negative relationship with a coefficient of -0.69 for secondary BAs as lithocholic acid (LCA) and deoxycholic acid (DCA). Discussion: The profile of BA metabolism of individuals who share the same food in the same environment appears to be unique, suggesting that the inherent ability of different individuals to adapt to diet and environment varies. Since the transition from the free diet in open space to whole prepackaged space food diet in a space station simulator causes the variations of BAs pool in an individual manner, assessment of BA metabolic profiles provides a new perspective for personalized diet design, astronaut selection and training, and space flight diet acclimatization.

Simulated manned Mars exploration: effects of dietary and diurnal cycle variations on the gut microbiome of crew members in a controlled ecological life support system.

BACKGROUND: Changes in gut microbiome are closely related to dietary and environment variations, and diurnal circle interventions impact on human metabolism and the microbiome. Changes in human gut microbiome and serum biochemical parameters during long-term isolation in a controlled ecological life support system (CELSS) are of great significance for maintaining the health of crewmembers. The Green Star 180 project performed an integrated study involving a four-person, 180-day duration assessment in a CELSS, during which variations in gut microbiome and the concentration of serum 25-hydroxyvitamin D, α-tocopherol, retinol and folic acid from the crewmembers were determined. RESULTS: Energy intake and body mass index decreased during the experiment. A trade-off between Firmicutes and Bacteroidetes during the study period was observed. Dynamic variations in the two dominant genus Bacteroides and Prevotella indicated a variation of enterotypes. Both the evenness and richness of the fecal microbiome decreased during the isolation in the CELSS. Transition of diurnal circle from Earth to Mars increased the abundance of Fusobacteria phylum and decreased alpha diversity of the fecal microbiome. The levels of serum 25-hydroxyvitamin D in the CELSS were significantly lower than those outside the CELSS. CONCLUSIONS: The unique isolation process in the CELSS led to a loss of alpha diversity and a transition of enterotypes between Bacteroides and Prevotella. Attention should therefore be paid to the transition of the diurnal circle and its effects on the gut microbiome during manned Mars explorations. In particular, serum 25-hydroxyvitamin D levels require monitoring under artificial light environments and during long-term space flight. Large-scale studies are required to further consolidate our findings.