Effect of the external donors on the polymerization of 4-methyl-1-pentene with high activity MgCl2/TiCl4 catalytic system

In order to find out correlations between the structure of an external donor and the obtained polymer, the effects of different external donors on the activity and stereospecificity of the MgCl₂/TiCl₄ catalytic system in the bulk polymerization of 4-methyl-1-pentene (4MP) were carefully studied. Different silane compounds of the structure R_nSi(OR')_4-n (where: n = 1–3, R = alkyl/phenyl, R = alkyl) and Al(i-Bu)₃ (TIBA) were used as external donors and cocatalyst, respectively. The effect of the donor/TIBA mole ratio on the activity and stereospecificity of the catalytic system was studied. Some major effects were observed for the three different external donors, namely, Me₃Si(OMe), Me₂Si(OMe)₂, and Me₃Si(OBu)₃, in the 4MP polymerization process. It was observed that the effect of the external silane donor on the polymerization strongly depends upon the size of the alkoxy and hydrocarbon (alkyl/phenyl) groups which are attached to the silicon atom. A selective deactivation of the non-stereospecific centers, as well as a transformation of the non-stereospecific into isospecific centers, is assumed to occur. On the basis of the obtained results and literature data available for the propene polymerization, the concept of structural conformity between the ligand-surrounded active center and the monomer molecule was carried forward.     

Liposome System for Encapsulation of Spirulina platensis Protein Hydrolysates: Controlled-Release in Simulated Gastrointestinal Conditions,Structural and Functional Properties

This study aimed to evaluate the physicochemical, structural, antioxidant and antibacterial properties of chitosan-coated (0.5 and 1% CH) nanoliposomes containing hydrolyzed protein of Spirulina platensis and its stability in simulated gastric and intestine fluids. The chitosan coating of nanoliposomes containing Spirulina platensis hydrolyzed proteins increased their size and zeta potential. The fourier transform infrared spectroscopy (FT-IR) test showed an effective interaction between the hydrolyzed protein, the nanoliposome, and the chitosan coating. Increasing the concentration of hydrolyzed protein and the percentage of chitosan coating neutralized the decreasing effect of microencapsulation on the antioxidant activity of peptides. Chitosan coating (1%) resulted in improved stability of size, zeta potential, and poly dispersity index (PDI) of nanoliposomes, and lowered the release of the hydrolyzed Spirulina platensis protein from nanoliposomes. Increasing the percentage of chitosan coating neutralized the decrease in antibacterial properties of nanoliposomes containing hydrolyzed proteins. This study showed that 1% chitosan-coated nanoliposomes can protect Spirulina platensis hydrolyzed proteins and maintain their antioxidant and antibacterial activities.     

Obesity,Pregnancy and the Social Contract with Today’s Adolescents

Adolescent health and well-being are of great concern worldwide, and adolescents encounter particular challenges, vulnerabilities and constraints. The dual challenges of adolescent parenthood and obesity are of public health relevance because of the life-altering health and socioeconomic effects on both the parents and the offspring. Prevention and treatment strategies at the individual and population levels have not been successful in the long term, suggesting that adolescent pregnancy and obesity cannot be managed by more of the same. Here, we view adolescent obese pregnancy through the lens of the social contract with youth. The disruption of this contract is faced by today’s adolescents, with work, social and economic dilemmas which perpetuate socioeconomic and health inequities across generations. The lack of employment, education and social opportunities, together with obesogenic settings, increase vulnerability and exposure to lifelong health risks, affecting their offspring’s life chances too. To break such vicious circles of disadvantage and achieve sustainable solutions in real-world settings, strong efforts on the part of policymakers, healthcare providers and the community must be oriented towards guaranteeing equity and healthy nutrition and environments for today’s adolescents. The involvement of adolescents themselves in developing such programs is paramount, not only so that they feel a sense of agency but also to better meet their real life needs.     

Phenolic constituents in dried flowers of aloe vera (Aloe barbadensis) and their in vitro antioxidative capacity

The dried flowers from Aloe vera (L.) Burm. f. (Aloe barbadensis Mill.) (Asphodelaceae) were analysed by means of HPLC-DAD and HPLC-MS/MS, verifying chlorogenic, caffeic, 5-P-coumaroylquinic, caffeoylshikimic, 5-feruloylquinic, 5-P-CIS-coumaroylquinic, P-coumaric and ferulic acid as well as luteolin, apigenin, quercetin, kaempferol, isoorientin, isovitexin and their 7-O-glucosides, saponarin and lutonarin. On searching for anthranoids in the flower extract, aloe-emodin as well as the glycosylchromone aloeresin B could be identified. Aloin A and B, the laxative principle of the drug Cura?ao-Aloes, are not accumulated in the dried flowers. The polyphenol content of three different batches was 0.73 - 1.01% (+/- 0.05%) and the flavonoid content 0.24 - 0.34% (+/- 0.01%). The hydrophilic antioxidative capacity amounted to 85.7 - 94.9 (+/- 0.5) micromol TEAC/g dried Aloe vera flower and was directly correlated with the polyphenol and flavonoid contents.     

Serum Levels of Interleukin-1β and Disease Progression in Multiple Myeloma Patients: A Case and Control Study

Objective:Multiple myeloma (MM) is known as an incurable heterogeneous plasma cell malignancy that presents with a variety of clinical manifestations. Inflammation plays an important role in this disease. Cytokines and Chemokines cause the progression of the disease. One of them is interleukin-1β (IL-1β), which may be involved in the pathogenesis of MM. Other markers such as calcium, albumin, creatinine, globulins, and total protein are also used to diagnose and prognosis patients. The main purpose of this study was to evaluate the serum level of IL-1β and various forms of calcium (total calcium, ionized calcium, and corrected calcium), albumin, creatinine, globulin, and total protein on stage-I of MM patients and healthy controls. Methods:Serum samples from 30 stage-I MM patients and 30 healthy subjects as controls were examined in this study. The protein concentrations of serum IL-1β was assessed by enzyme-linked immunosorbent assay (ELISA), total calcium, albumin, creatinine, total protein, and globulin Measured by auto analyzer BT3000, an electrolyte analyzer was used to measure ionized calcium (Ca++) and a special equation was used to calculate the corrected calcium. Result:The mean level of IL-1β was significantly elevated in stage-I MM. The mean levels of IL-1β were 7.04±1.15 ng/ml in stage-I MM and 3.12± 0.90 ng/ml in controls (p<0.001). The mean levels of total calcium (total Ca) were 9.45±0.56 mg/dl in stage-I MM and 9.09±0.43mg/dl in controls (p=0.008). The mean levels of ionized calcium (Ca++) was 4.65±0.28mg/dl in stage-I MM and 4.75±0.33mg/dl in controls (p=0.2). The mean ratio of serum ionized calcium to total calcium (Ca++/ total Ca) was 0.49±0.054 in stage-I MM and 0.52±0.047 in controls (p=0.02). The mean ratio of serum ionized calcium to corrected calcium (Ca++/corrected Ca) was 0.42±0.033 in stage-I MM and the Mean ratio of serum ionized calcium to calcium total (Ca++/ total Ca) was 0.52±0.047 in controls, Comparison of the mean of the two groups shows a significant difference (p<0.001). The mean level of albumin was 1.72±0.35 g/dl in stage-I MM and4.32±0.41g/dl in controls (p<0.001). The mean level of total protein was 12.65±0.81g/dl in stage-I MM and 7.07±0.4 g/dl in controls (p<0.001). The mean level of globulin was 11.00±0.96 mg/dl in stage-I MM and 2.85±0.77 mg/dl in controls (p<0.001). The mean level of creatinine was 1.15±0.25 mg/dl in stage-I MM and 0.96±0.15 mg/dl in controls (p=0.001). Conclusion:The results of the study indicate the possible involvement of IL-1β at stage-I MM and it can indicate the role of chemokines in the disease process, especially in the early stages. Changes in the chemical profiles mentioned can help in the diagnosis and prognosis of the disease.Key Words: Multiple myeloma, interleukin- 1β- total calcium, ionized calcium, corrected calcium, albumin, creatinine     

Associations of Nutritional,Environmental, and Metabolic Biomarkers with Diabetes-Related Mortality in U.S. Adults: The Third National Health and Nutrition Examination Surveys between 1988–1994 and 2016

Background: Nutritional, environmental, and metabolic status may play a role in affecting the progression and prognosis of type 2 diabetes. However, results in identifying prognostic biomarkers among diabetic patients have been inconsistent and inconclusive. We aimed to evaluate the associations of nutritional, environmental, and metabolic status with disease progression and prognosis among diabetic patients. Methods: In a nationally representative sample in the NHANES III (The Third National Health and Nutrition Examination Survey, 1988–1994), we analyzed available data on 44 biomarkers among 2113 diabetic patients aged 20 to 90 years (mean age: 58.2 years) with mortality data followed up through 2016. A panel of 44 biomarkers from blood and urine specimens available from NHANES III were included in this study and the main outcomes as well as the measures are mortalities from all-causes. We performed weighted logistic regression analyses after controlling potential confounders. To assess incremental prognostic values of promising biomarkers beyond traditional risk factors, we compared c-statistics of the adjusted models with and without biomarkers, separately. Results: In total, 1387 (65.2%) deaths were documented between 1988 and 2016. We observed an increased risk of all-cause mortality associated with higher levels of serum C-reactive protein (p for trend = 0.0004), thyroid stimulating hormone (p for trend = 0.04), lactate dehydrogenase (p for trend = 0.02), gamma glutamyl transferase (p for trend = 0.02), and plasma fibrinogen (p for trend = 0.03), and urine albumin (p for trend < 0.0001). In contrast, higher levels of serum sodium (p for trend = 0.005), alpha carotene (p for trend = 0.006), and albumin (p for trend = 0.005) were associated with a decreased risk of all-cause mortality. In addition, these significant associations were not modified by age, sex, or race. Inclusion of thyroid stimulating hormone (p = 0.03), fibrinogen (p = 0.01), and urine albumin (p < 0.0001), separately, modestly improved the discriminatory ability for predicting all-cause mortality among diabetic patients. Conclusions: Our nationwide study findings provide strong evidence that some nutritional, environmental, and metabolic biomarkers were significant predictors of all-cause mortality among diabetic patients and may have potential clinical value for improving stratification of mortality risk.