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51.
52.
The objective of the present study is to improve iron bioavailability using high-density gastroretentive pellets of zero valent iron nanoparticles (ZVINPs). ZVINPs were prepared by the chemical reduction method and were characterized for surface morphology, surface charge, and thermal properties. High-density gastroretentive pellets of iron nanoparticles were prepared using spheronization technique. Pellets were characterized for its micromeritic properties, in vitro drug release, and ex vivo permeability. The pharmacokinetic parameters, organ distribution, and toxicity of the optimized pellets were investigated in Wistar rats. In vivo results revealed more than 2-fold increases in oral bioavailability of iron by pellets compared to plane ferrous sulfate. Toxicological studies of the carriers indicated no evidence of liver damage in acute treatment; however, few complications were observed in chronic treatment groups. These results indicated that ZVINPs pellets successfully improve the oral iron bioavailability but need to obtain more information on repeated dose toxicity to initiate the clinical evaluation of investigational products. 相似文献
53.
Oğuzhan Bol Serhat Koyuncu Nurullah Günay 《Journal of occupational medicine and toxicology (London, England)》2018,13(1):35
Background
Carbon monoxide (CO) is formed as a result of the incomplete burning of hydrocarbon-containing fuels such as natural gas, coal, liquid petroleum gas, and wood. CO is a colorless, odorless, and poisonous gas that produces various acute and chronic effects in CO-exposed people. In this study, we aimed to measure CO levels in auto care repairmen with chronic CO-related illnesses using a serial, non-invasive method.A prospective cohort study.Methods
A total of 99 people from six different auto-repair services were included in the study. Carboxyhemoglobin (COHb) levels were measured at four different times with 2-hour intervals starting at 08:00 AM. Data concerning employees’ ages, working hours, smoking statuses, and types of home heating fuel were collected. A control group of 100 cases was created based on this data. The measurements were done on the control group in the morning with a Masimo Rad-57 CO-oximeter.Results
The highest mean (± SD) COHb value was 7.04%?±?3.32% after the third measurement. The mean value for the control group was 1.61%?±?1.43%. A statistically significant difference between the groups was found for each value.Discussion
We determined that the risk of being affected by CO is high in buildings in which the auto services were located. The effects of chronic or prolonged exposure to low amounts of CO were found to be ambiguous. However, in some studies, it was found that low-grade CO exposure could lead to coronary artery disease and some neurological complications. Therefore, it is necessary to be careful about the health of employees who have been exposed to CO.Conclusions
We concluded that there is a need for more detailed studies concerning chronic CO poisoning. Also, in workplaces in which there is high exposure to CO, proper workplace safety measures should be taken to reduce this gas’s harmful effects to employees.54.
Katrin Christiane Reber Hans-Helmut König André Hajek 《Journal of occupational medicine and toxicology (London, England)》2018,13(1):33
Background
So far, studies within the occupational field have largely concentrated on working conditions and job stressors and staff members’ or subordinate health. Only a few have focused on managers in this context, but studies are missing that explicitly look at the relation between leadership position and health care use (HCU). Thus, the purpose of this study was to examine the potential effects of a change in leadership position on HCU in women and men longitudinally.Methods
Data were drawn from a nationally representative longitudinal study in Germany (German Socio-Economic Panel, GSOEP). Data from 2009 and 2013 were used. Leadership position was divided into (i) top management, (ii) middle management, (iii) lower management, and (iv) a highly qualified specialist position. The number of physician visits in the preceding 3 months were used to quantify HCU (n?=?2140 observations in regression analysis; 69% male).Results
Adjusting for various potential confounders (e.g., age, self-rated health, chronic conditions, and personality factors), Poisson FE regression analysis revealed that changes from a highly qualified specialist position to the top management were associated with a decrease in the number of physician visits in men (β?=?.47, p?<?.05), but not in women. Gender differences (gender x leadership position) were significant.Conclusions
Findings of this study emphasize the impact of leadership positions on the number of physician visits in men. Further study is required to elucidate the underlying mechanisms.55.
Ralf Schiel Thomas Perenthaler Sabine Müller Antje Steveling 《Pr?vention und Gesundheitsf?rderung》2018,13(2):170-178
Background
Medical rehabilitation plays a special role in the treatment of children and adolescents with diabetes mellitus: services which are difficult to implement in an out-patient or an acute in-patient setting can be provided. The study analyzed changes over a period of 12 years.Methods
In a monocentric, retrospective cross-sectional analysis, all (n = 2001) children and adolescents with diabetes (52% girls, age 12.6 ± 4.9 years) who were admitted to a specialist clinic for rehabilitation during the period 01/2004–12/2016 were examined.Results
The duration of medical rehabilitation was 27.3 ± 6.1 days. In all, 1980 of 2001 (98.9%) children and adolescents had type 1 diabetes, while 21 of 2001 (1.1%) had type 2 diabetes. Mean HbA1c was 7.87 ± 1.47%. Overall, 1897 of 2001 (95%) patients had an intensified insulin therapy, of which 633 (32%) used insulin pumps (CSII). They injected 0.86 ± 0.47?I.?U. insulin/kg body weight/day and performed 37.6 ± 11.4 blood glucose self-tests/week. The number of patients who participated in medical rehabilitation decreased: In 2016 it was 68% lower than in 2007, the year of the highest number of patients (p < 0.05). Parameters of metabolic control hardly changed. The proportion of patients with CSII increased (p < 0.05). In particular, young children used CSII more frequently (59% in <4 year olds vs 24% in 16–17 year olds, p < 0.05). Changes also occurred in cultural status: The percentage of patients from German families decreased (p < 0.05); the proportion of patients from mixed-cultural families increased (p < 0.05). The number of patients living together with both parents also decreased (p < 0.05 for the tendency); the number of patients living with single parents increased (p < 0.05 for the tendency). In young children, HbA1c values were the lowest. From the beginning of puberty (about 10 years), HbA1c increased (8.5 ± 1.9% in 16–17 year olds). There were no correlations/associations between metabolic control and the incidences of hypoglycemia/ketoacidoses.Conclusions
There has been a change in medical rehabilitation: The number of patients has decreased, the proportion of patients using CSII has increased, the number of patients living with single parents and the percentage of patients from a culturally mixed families has also increased. Thus, there are new challenges in medical rehabilitation.56.
Michelle Z. Dion Danielle Leiske Vikas K. Sharma Christina L. Zuch de Zafra Cleo M. Salisbury 《Pharmaceutical research》2018,35(11):222
Purpose
Biotherapeutics can be susceptible to oxidation during manufacturing and storage. Free L-methionine is known to protect methionine residues in proteins from oxidation. Similarly, free tryptophan and other indole derivatives have been shown to protect tryptophan residues from oxidation. N-acetyl-DL-tryptophan was previously identified as a potentially superior antioxidant to tryptophan as it has a lower oxidation potential and produces less peroxide upon light exposure. This study sought to confirm the antioxidant efficacy and safety of N-acetyl-DL-tryptophan and L-methionine as formulation components for biotherapeutic drugs.Methods
Antibodies were subjected to AAPH and light exposure in the presence of N-acetyl-DL-tryptophan and L-methionine. Oxidation in relevant CDR and Fc residues was quantified by peptide map. In silico, in vitro, and in vivo studies were performed to evaluate the safety of N-acetyl-DL-tryptophan and L-methionine.Results
Peptide mapping demonstrated that N-acetyl-DL-tryptophan was effective at protecting tryptophans from AAPH stress, and that the combination of N-acetyl-DL-tryptophan and L-methionine protected both tryptophan and methionine from AAPH stress. The safety assessment suggested an acceptable safety profile for both excipients.Conclusions
N-acetyl-tryptophan and L-methionine effectively reduce the oxidation of susceptible tryptophan and methionine residues in antibodies and are safe for use in parenteral biotherapeutic formulations.57.
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