Preanalytical stability of molecular forms of prostate-specific antigen in serum samples (PSA, free PSA, [-2]proPSA) and their impact on fPSA/tPSA ratio and PHI.

BACKGROUND: Prostate cancer is a common cancer in men. Detection methods include the measurement of biomarkers: prostate-specific antigen (PSA), free PSA, [-2]proPSA, and the calculated indices: fPSA/tPSA ratio and Prostate Health Index (PHI). Proper preanalytical conditions are crucial for precise measurement and failure to adhere to protocols or regulations can influence the diagnostic algorithm. We assessed the stability of the above-mentioned biomarkers, fPSA/tPSA ratio and PHI, under various pre-analytical conditions. METHODS: Serum samples from 45 males were collected and stored under specific conditions before tPSA, fPSA, and [-2]proPSA were measured. Subsequently, the fPSA/tPSA and PHI were calculated. RESULTS: tPSA, fPSA, and [-2]proPSA remained stable during the two freeze-thaw cycles. Storage at 4°C and 22°C resulted in stable tPSA concentrations. However, fPSA levels decreased and [-2]proPSA levels increased over time. The fPSA/tPSA ratio remained stable for 72 h, at which point a decrease was observed in the samples kept at 4°C and 22°C. A gradual increase in PHI was observed in the samples kept at 4°C and 22°C. CONCLUSIONS: All biomarkers remained stable during two freeze-thaw cycles. tPSA was the most stable analyte when stored at 4°C, as well as at RT. A gradual increase of [-2]proPSA and a slight decrease in fPSA were observed during the storage test. This led to a decrease in the fPSA/tPSA ratio and an elevation in the PHI. We therefore recommend measuring prostate biomarkers promptly following blood collection. IMPACT: Understanding the pre-analytical stability of prostate biomarkers helps prevent false positive results and improve the accuracy of diagnostics for prostate cancer.

The impact of obesity, age, and gender on plasmatic levels of selected glycoprotein biomarkers and miRNA-499 in OSA patients.

BACKGROUND: The current obstructive sleep apnea (OSA) diagnostic uses polysomnography or limited polygraphy and requires specialized personnel and technical equipment. Glycoprotein biomarkers and microRNAs are being explored as a possible new method for screening. We aimed to evaluate whether certain biomarkers and microRNA, previously identified as related to OSA, could be influenced by factors such as gender, age, and obesity level in patients with OSA. METHODS: In this retrospective analytical study, patients with moderate to severe OSA (n = 130) were compared with the control group. Serum levels of selected biomarkers and microRNA were taken from both groups. The group of OSA patients was then stratified by gender, obesity level, and age to see the possible influence of those variables on biomarker levels. RESULTS: Levels of all studied biomarkers - C-reactive protein (CRP), high-sensitivity troponin I (hsTnI), pentraxin-3 (PTX-3), and microRNA-499 were significantly higher in patients with OSA compared to the control group. In the OSA group only hsTnI showed a statistically significant relationship with gender. Levels of CRP and hsTnI showed a significant dependence on the level of obesity. Dependency on age was proven for hsTnI. CRP, PTX-3, and microRNA-499 did not have any statistically significant relationship with age. CONCLUSION: We found that serum levels of pentraxin-3 and microRNA-499 in patients with moderate to severe obstructive sleep apnoea are independent of gender, obesity, and age. CRP was affected by the level of obesity and hsTnI was influenced by all 3 variables. We consider these findings important for further research of OSA biomarkers.

Safety and efficacy of one and two booster doses of SARS-CoV-2 mRNA vaccines in kidney transplant recipients: A randomized clinical trial.

BACKGROUND: Kidney transplant recipients are at risk for a severe course of COVID-19 with a high mortality rate. A considerable number of patients remains without a satisfactory serological response after the baseline and adjuvant SARS-CoV-2 vaccination schedule. METHODS: In this prospective, randomized study, we evaluated the efficacy and safety of one and two booster doses of mRNA vaccines (either mRNA-1273 or BNT162b2) in 125 COVID-19 naive, adult kidney transplant recipients who showed an insufficient humoral response (SARS-CoV-2 IgG <10 AU/ml) to the previous 2-dose vaccination schedule. The primary outcome was the difference in the rate of a positive antibody response (SARS-CoV-2 IgG ≥10 AU/ml) between one and two booster doses at 1 month after the final booster dose. RESULTS: A positive humoral response was observed in 36 (62%) patients receiving two booster doses and in 28 (44%) patients receiving one booster dose (odds ratio [OR], 2.10, 95% confidence interval [CI], 1.02-4.34, p = .043). Moreover, median SARS-CoV-2 IgG levels were higher with two booster doses (p = .009). The number of patients with positive virus neutralizing antibody (VNA) levels was numerically higher with two booster doses compared to one booster dose, but without statistical significance (66% vs. 50%, p = .084). There was no significant difference in positive seroconversions rate and antibody levels between mRNA-1273 and BNT162b2. CONCLUSION: A higher number of kidney transplant recipients achieved a positive antibody response after two booster doses compared to one booster dose.

Insufficient response to mRNA SARS-CoV-2 vaccine and high incidence of severe COVID-19 in kidney transplant recipients during pandemic.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mRNA vaccination may fail to sufficiently protect transplant recipients against coronavirus disease 2019 (COVID-19). We retrospectively evaluated COVID-19 in kidney transplant recipients (n = 226) after BNT162b2 mRNA vaccine administration. The control group consisted of unvaccinated patients (n = 194) during the previous pandemic wave. We measured anti-spike protein immunoglobulin G (IgG) levels and cellular responses, using enzyme-linked immunosorbent spot assay, in a prospective cohort after vaccination (n = 31) and recovery from COVID-19 (n = 19). COVID-19 was diagnosed in 37 (16%) vaccinated and 43 (22%) unvaccinated patients. COVID-19 severity was similar in both groups, with patients exhibiting a comparable need for hospitalization (41% vs. 40%, p = 1.000) and mortality (14% vs. 9%, p = .726). Short posttransplant periods were associated with COVID-19 after vaccination (p < .001). Only 5 (16%) patients achieved positive SARS-CoV-2 IgG after vaccination, and 17 (89%, p < .001) recovered from COVID-19 (median IgG levels, 0.6 vs. 52.5 AU/ml, p < .001). A cellular response following vaccination was present in the majority (n = 22, 71%), with an increase in interleukin 2 secreting T cells (p < .001). Despite detectable T cell immunity after mRNA vaccination, kidney transplant recipients remained at a high risk of severe COVID-19. Humoral responses induced by vaccination were significantly lower than that after COVID-19.

High leptin status indicates an increased risk of mortality and heart failure in stable coronary artery disease.

BACKGROUND AND AIMS: Leptin is an adipocyte-derived peptide involved in energy homeostasis and body weight regulation. The position of leptin in cardiovascular pathophysiology remains controversial. Some studies suggest a detrimental effect of hyperleptinemia on the cardiovascular (CV) system, while others assume the role of leptin as a neutral or even protective factor. We have explored whether high leptin affects the mortality and morbidity risk in patients with stable coronary heart disease. METHODS AND RESULTS: We followed 975 patients ≥6 months after myocardial infarction or coronary revascularization in a prospective study. All-cause or cardiovascular death, non-fatal cardiovascular events (recurrent myocardial infarction, stroke, or any revascularization), and hospitalizations for heart failure (HF) we used as outcomes. High serum leptin concentrations (≥18.9 ng/mL, i.e., 4th quartile) were associated with worse survival, as well as with a higher incidence of fatal vascular events or hospitalizations for HF. Even after full adjustment for potential covariates, high leptin remained to be associated with a significantly increased 5-years risk of all-cause death [Hazard risk ratio (HRR) 2.10 (95%CIs:1.29-3.42), p < 0.003], CV death [HRR 2.65 (95%CIs:1.48-4.74), p < 0.001], and HF hospitalization [HRR 1.95 (95% CIs:1.11-3.44), p < 0.020]. In contrast, the incidence risk of non-fatal CV events was only marginally and non-significantly influenced [HRR 1.27 (95%CIs:0.76-2.13), p = 0.359]. CONCLUSIONS: High leptin concentration entails an increased risk of mortality, apparently driven by fatal CV events and future worsening of HF, on top of conventional CV risk factors and the baseline status of left ventricular function.

The coincidence of low vitamin K status and high expression of growth differentiation factor 15 may indicate increased mortality risk in stable coronary heart disease patients.

BACKGROUND AND AIMS: Matrix Gla protein (MGP) is a natural inhibitor of vascular calcification critically dependent on circulating vitamin K status. Growth differentiation factor 15 (GDF-15) is a regulatory cytokine mainly of the inflammatory and angiogenesis pathways, but potentially also involved in bone mineralization. We sought to determine whether these two circulating biomarkers jointly influenced morbidity and mortality risk in patients with chronic coronary heart disease (CHD). METHODS AND RESULTS: 894 patients ≥6 months after myocardial infarction and/or coronary revascularization at baseline were followed in a prospective study. All-cause and cardiovascular mortality, non-fatal cardiovascular events (myocardial infarction, stroke, any revascularization), and hospitalization for heart failure (HF) were followed as outcomes. Desphospho-uncarboxylated MGP (dp-ucMGP) was used as a biomarker of vitamin K status. Both, increased concentrations of dp-ucMGP (≥884 pmol/L) and GDF-15 (≥1339 pg/mL) were identified as independent predictors of 5-year all-cause or cardiovascular mortality. However, their coincidence further increased mortality risk. The highest risk was observed in patients with high dp-ucMGP plus high GDF-15, not only when compared with those with "normal" concentrations of both biomarkers [HR 5.51 (95% CI 2.91-10.44), p < 0.0001 and 6.79 (95% CI 3.06-15.08), p < 0.0001 for all-cause and cardiovascular mortality, respectively], but even when compared with patients with only one factor increased. This pattern was less convincing with non-fatal cardiovascular events or hospitalization for HF. CONCLUSIONS: The individual coincidence of low vitamin K status (high dp-ucMGP) and high GDF-15 expression predicts poor survival of stable CHD patients.

COVID-19 antibody testing: examination of the antibody response to coronavirus in common practice.

Antibody identification is an important diagnostic tool that allows us to confirm a past SARS-CoV-2 infection. While antibody tests in the Czech Republic are yet to receive the attention they deserve, in the USA antibody testing has already become part of the diagnostic algorithms. The aim of this publication is to provide comprehensive information on the topic of antibody testing, the kinetics of antibody production, the types of tests and the issue of virus neutralization tests. Special attention is paid to the correct interpretation of test results and the issues surrounding reinfection.

Antibodies from previous infection bring sufficient and long-term protection against COVID-19.

One of the basic manifestations of an adaptive anti-infective immunity is the production of specific antibodies. The presence of antibodies can be detected in serum and serves as one of the diagnostic tools used to confirm past infection. Very often it also serves as a confirmation that the body has acquired immunity to the disease. The appearance of COVID-19 has cast a shadow of doubt on these textbook examples of antibody behavior. Information that repeatedly questions antibody measurement and its significance has been circulating among professionals and the general public. The aim of our article is to summarize the current knowledge on the immunity acquired following SARS-CoV-2 infection and to present the results of antibody testing from four Czech laboratories which have been measuring these antibodies for over one year. Our data suggest that commonly available diagnostic methods reliably predict the results of a virus neutralization test, which is the gold standard of immunity detection. By acknowledging those with naturally acquired anti-infective immunity, in addition to vaccinated individuals, we will significantly increase the perceived level of collective immunity.

Preoperative prostate health index predicts adverse pathology and Gleason score upgrading after radical prostatectomy for prostate cancer.

BACKGROUND: We aimed to explore the utility of prostate specific antigen (PSA) isoform [- 2] proPSA and its derivatives for prediction of pathological outcome after radical prostatectomy (RP). METHODS: Preoperative blood samples were prospectively and consecutivelyanalyzed from 472 patients treated with RP for clinically localized prostate cancerat four medical centers. Measured parameters were PSA, free PSA (fPSA), fPSA/PSA ratio, [- 2] proPSA (p2PSA), p2PSA/fPSA ratio and Prostate Health Index (PHI)(p2PSA/fPSA)*√PSA]. Logistic regression models were fitted to determine the accuracy of markers for prediction of pathological Gleason score (GS) ≥7, Gleason score upgrading, extracapsular extension of the tumor (pT3) and the presence of positive surgical margin (PSM). The accuracy of predictive models was compared using area under the receiver operating curve (AUC). RESULTS: Of 472 patients undergoing RP, 339 (72%) were found to have pathologic GS ≥ 7, out of them 178 (53%) experienced an upgrade from their preoperative GS = 6. The findings of pT3 and PSM were present in 132 (28%) and 133 (28%) cases, respectively. At univariable analysis of all the preoperative parameters, PHI was the most accurate predictor of pathological GS ≥7 (OR 1.02, 95% CI 1.01-1.03, p<0.001), GS upgrading (OR 1.02, 95% CI 1.01-1.03, p<0.003), pT3 disease (OR 1.01, 95% CI 1.00-1.02, p<0.007) and the presence of PSM (OR 1.01, 95% CI 1.00-1.02, p<0.002). Adding of PHI into the base multivariable model increased significantly the accuracy for prediction of pathological GS by 4.4% to AUC = 66.6 (p = 0.015) and GS upgrading by 5.0% to AUC = 65.9 (p = 0.025), respectively. CONCLUSIONS: Preoperative PHI levels may contribute significantly to prediction of prostate cancer aggressiveness and expansion of the tumor detected at final pathology.

One-step nucleic acid amplification vs ultrastaging in the detection of sentinel lymph node metastasis in endometrial cancer patients.

BACKGROUND AND OBJECTIVES: Utilisation of the one-step nucleic acid amplification (OSNA) molecular biology method for the detection of the metastatic involvement of sentinel lymph nodes (SLNs) in endometrial cancer (EC) patients. A comparison with histopathological ultrastaging and a description of the clinical consequences. METHODS: Surgically treated EC patients underwent detection of SLNs. Nodes greater than 5 mm were cut into sections 2-mm thick parallel to the short axis of the node. Odd sections were examined according to the OSNA method, while even ones according to an appropriate ultrastaging protocol. Nodes less than or equal to 5 mm were cut into halves along the longitudinal axis with one half examined according to the OSNA method and the other half by ultrastaging. RESULTS: Fifty-eight patients were included and 135 SLNs were acquired. Both ultrastaging and OSNA agreed on 116 results. According to the OSNA method, 20.69% more patients were classified into International Federation of Gynecology and Obstetrics (FIGO) stage III. When comparing the results of the OSNA method to the conclusions of ultrastaging as a reference method, sensitivity of 90.9%, specificity of 85.5% and concordance of 85.9% were attained. CONCLUSIONS: The results of the OSNA method showed a higher frequency of detection of micrometastases and included 20.69% more patients into FIGO stage III.

Improved prediction of CPAP failure using T90, age and gender.

Sleep apnea syndrome is associated with increased risk of cardiovascular disease. In treating older patients, there is a special emphasis put on minimally invasive and conservative procedures and a simple method for predicting the potential for treatment success is essential. Continuous positive airway pressure (CPAP) is the first choice for treatment, however, it is not always successful. In cases where CPAP was unsuccessful, treatment with bilevel positive airway pressure (BiPAP) is the next treatment option. In this study, we examine commonly evaluated respiratory parameters, obesity, and age relative to their ability to predict CPAP failure. We also tried to find differences in the predictive ability of these parameters in older and younger patients. The predictive ability, relative to CPAP failure, was examined for each individual parameter as well as for combinations of parameters. All variables had a statistical association with CPAP failure; failure prediction reliability ranged from poor to moderate. Combining T90, age, and gender can be used to find patients who will benefit from BiPAP as the first choice for treatment. An initial BiPAP indication can produce relevant reductions in treatment cost.

Detection and Quantification of Carbohydrate-Deficient Transferrin by MALDI-Compatible Protein Chips Prepared by Ambient Ion Soft Landing.

BACKGROUND: Transferrin is synthetized in the liver and is the most important iron-transport carrier in the human body. Severe alcohol consumption leads to alterations in glycosylation of transferrin. Mass spectrometry can provide fast detection and quantification of transferrin isoforms because they have different molecular masses. In this study, we used antibody chips in combination with MALDI-TOF MS for the detection and quantification of transferrin isoforms. METHODS: Protein chips were prepared by functionalization of indium tin oxide glass using ambient ion soft landing of electrosprayed antitransferrin antibody. Two microliters of patient serum was applied on the antibody-modified spots, and after incubation, washing, and matrix deposition, transferrin isoforms were detected by MALDI-TOF MS. Peak intensities of each transferrin form were used to calculate total carbohydrate-deficient transferrin (CDT). The CDT values obtained by the MALDI chip method were compared with the results obtained by a standard capillary electrophoresis (CE). RESULTS: The chip-based MALDI-TOF MS method was used for enrichment and detection of CDT from human serum. A sample cohort from 186 patients was analyzed. Of these samples, 44 were positively identified as belonging to alcoholic patients, whereas 142 were negative by the MALDI chip approach. The correlation of the data obtained by the CE and the chip-based MALDI was r = 0.986, 95% CI. CONCLUSIONS: Functionalized MALDI chips modified by antitransferrin antibody prepared by ambient ion soft landing were successfully used for detection and quantification of CDT from human sera.

Effect of long-term using of hormonal contraception on anti-Müllerian hormone secretion.

Anti-Müllerian hormone (AMH) is an important factor associated with female fertility and the ovarian reserve. There are several past studies available concerning the influence of hormonal contraception (HC) on serum AMH levels. Recent studies have reported that AMH levels in women using HC can be about 30% lower compared to those not using HC. However, earlier studies showed no reduction in AMH levels in HC users. We decided to evaluate the effects of long-term HC use (mean duration of HC use: 11.4 years) on AMH levels in women. To exclude potential shorter and reversible decreasing effects of HC on fertility function, we decided to include women in the study who had stopped using HC 1 year before the AMH sample collection. We examined 105 women who used HC and 44 women who had never used HC. The median concentration of AMH in the group of long-term users of HC was 2.89 and 3.37 ng/ml in the group of women who had never used HC. We found no statistically significant difference (p = 0.3261). In conclusion, we observed no negative impact of HC on the AMH serum levels. AMH can be used as an ovarian reserve marker for these women.

A Case Study of Vitamin D Supplementation Therapy and Acute Respiratory Tract Infection.

BACKGROUND: Low serum concentrations of 25-hydroxyvitamin D correlate with higher susceptibility to acute respiratory tract infections (ARTIs). The case study presented here aims at sheding light on the correlation between vitamin D levels, the vitamin D supplement dose, and the incidence of ARTIs. CASE REPORT: A 23-year-old female patient with a vitamin D insufficiency was able to successfully increase her vitamin D levels from 45.60 nmol/l to 85.91 nmol/l (reference ranges 75-200 nmol/l) through the use of supplements. However, it was surprising to observe a decrease in vitamin D levels even though the patient continued taking supplements. Further examination indicated that the patient was experiencing common symptoms of an acute respiratory tract infection (ARTI). This case highlights the intricate connection between ARTIs and vitamin D intake. CONCLUSION: This case study clearly demonstrates the intricate connection between vitamin D levels, supplement treatment, and ARTIs. The observed decrease in vitamin D levels during the course of supplementation, while the patient was suffering from an ARTI, suggests that respiratory infections may affect vitamin D metabolism.

Newborn Hearing Screening - An Implementation Analysis.

BACKGROUND/AIM: Hearing impairment affects a small but significant percentage of newborns (0.1-0.4%). Newborn hearing screening (NHS) is recommended for early detection and treatment. The implementation of NHS can vary among countries. In this study, we present the methodology, organization, and technical requirements of NHS. This study analyzed results from a tertiary hospital, identified issues, and proposed solutions. PATIENTS AND METHODS: In the studied region, there are five maternity hospitals and a perinatal intensive care center and in 2020, there were 5,864 live births. Screening is performed at three levels. The first screening is conducted on the 2nd-3rd day of a newborn's life in a maternity hospital, the first rescreening on the 3rd-6th week at a relevant ENT department, and the second rescreening on the 3rd-6th month of life at the regional screening center where the central database is also held. RESULTS: In the studied region, 5,793 out of 5,864 (98.79%) newborns received NHS in 2020. Of these, 120 (2.07%) were tested positive on their first screening. Ninety-four patients (78.3%) of those attended the ENT department for a first rescreening. Thirty-four patients (0.59% of total) were tested positive again and referred to the regional screening center. Out of the 27 patients who attended the second rescreening, four (0.07% of the total) were ultimately diagnosed with hearing impairment. CONCLUSION: Our study found that newborn hearing screening (NHS) in our region achieved a high compliance rate of 98.8% for initial screenings in 2020. However, challenges remain in the rescreening process due to data management issues, inter-regional cooperation, and public awareness. The recent implementation of mandatory screenings, updated guidelines, and a centralized database is expected to enhance the effectiveness of NHS. Further research is needed to evaluate these improvements.

Glycoprofiling of proteins as prostate cancer biomarkers: A multinational population study.

The glycoprofiling of two proteins, the free form of the prostate-specific antigen (fPSA) and zinc-α-2-glycoprotein (ZA2G), was assessed to determine their suitability as prostate cancer (PCa) biomarkers. The glycoprofiling of proteins was performed by analysing changes in the glycan composition on fPSA and ZA2G using lectins (proteins that recognise glycans, i.e. complex carbohydrates). The specific glycoprofiling of the proteins was performed using magnetic beads (MBs) modified with horseradish peroxidase (HRP) and antibodies that selectively enriched fPSA or ZA2G from human serum samples. Subsequently, the antibody-captured glycoproteins were incubated on lectin-coated ELISA plates. In addition, a novel glycoprotein standard (GPS) was used to normalise the assay. The glycoprofiling of fPSA and ZA2G was performed in human serum samples obtained from men undergoing a prostate biopsy after an elevated serum PSA, and prostate cancer patients with or without prior therapy. The results are presented in the form of an ROC (Receiver Operating Curve). A DCA (Decision Curve Analysis) to evaluate the clinical performance and net benefit of fPSA glycan-based biomarkers was also performed. While the glycoprofiling of ZA2G showed little promise as a potential PCa biomarker, the glycoprofiling of fPSA would appear to have significant clinical potential. Hence, the GIA (Glycobiopsy ImmunoAssay) test integrates the glycoprofiling of fPSA (i.e. two glycan forms of fPSA). The GIA test could be used for early diagnoses of PCa (AUC = 0.83; n = 559 samples) with a potential for use in therapy-monitoring (AUC = 0.90; n = 176 samples). Moreover, the analysis of a subset of serum samples (n = 215) revealed that the GIA test (AUC = 0.81) outperformed the PHI (Prostate Health Index) test (AUC = 0.69) in discriminating between men with prostate cancer and those with benign serum PSA elevation.

The Stability of the Anti-Müllerian Hormone in Serum and Plasma Samples under Various Preanalytical Conditions.

The anti-Müllerian hormone (AMH) is a glycoprotein that plays an important role in prenatal sex differentiation. It is used as a biomarker in polycystic ovary syndrome (PCOS) diagnostics, as well as for estimating an individual's ovarian reserve and the ovarian response to hormonal stimulation during in vitro fertilization (IVF). The aim of this study was to test the stability of AMH during various preanalytical conditions that are in accordance with the ISBER (International Society for Biological and Environmental Repositories) protocol. Plasma and serum samples were taken from each of the 26 participants. The samples were then processed according to the ISBER protocol. AMH levels were measured in all the samples simultaneously using the chemiluminescent kit ACCESS AMH in a UniCel® DxI 800 Immunoassay System (Beckman Coulter, Brea, CA, USA). The study proved that AMH retains a relatively high degree of stability during repeated freezing and thawing in serum. AMH was shown to be less stable in plasma samples. Room temperature proved to be the least suitable condition for the storage of samples before performing the biomarker analysis. During the testing of storage stability at 5-7 °C, the values decreased over time for all the plasma samples but remained stable in the serum samples. We proved that AMH is highly stable under various stress conditions. The anti-Müllerian hormone retained the greatest stability in the serum samples.

Life Cycle Assessment of River Sand and Aggregates Alternatives in Concrete.

Urbanization processes in Asia are still ongoing; thus, aggregate demand is expected to increase in following years. Even though construction and demolition waste is a source for secondary building materials in industrialized countries, it is not yet an alternative construction material source in Vietnam as the urbanization process is still ongoing. Thus, there is a need for river sand and aggregates alternatives in concrete, namely manufactured sand (m-sand) from primary solid rock materials and secondary waste materials. The focus in the present study for Vietnam was on m-sand sand as alternative for river sand, and different ashes as alternatives for cement in concrete. The investigations comprised concrete lab tests according to the formulations of concrete strength class C 25/30 in accordance with DIN EN 206, followed by a lifecycle assessment study in order to identify the environmental impact of the alternatives. In total 84 samples were investigated, consisting of 3 reference samples, 18 samples with primary substitutes, 18 samples with secondary substitutes, and 45 samples with cement substitutes. This kind of holistic investigation approach comprising material alternatives and accompanying LCA was the first study for Vietnam, and even for Asia, and represents a substantial added value for future policy development in order to cope with resource scarcity. The results show that with the exception of metamorphic rocks, all m-sands meet the requirements for quality concrete. In terms of cement replacement, the mixes showed that a higher percentage of ash reduces the compressive strength. The compressive strength values of the mixes with up to 10% coal filter ash or rice husk ash were equivalent to the C25/30 standard concrete formulation. Higher ash contents up to 30% lead to the reduction of the concrete quality. The LCA study's results highlighted the better environmental footprints across environmental impact categories in the 10% substitution material in comparison to the use of primary materials. The LCA analysis results showed that cement as a component in concrete holds the highest footprint. The use of secondary waste as alternative for cement provides significant environmental advantage.

Vitamin D3 Supplementation: Comparison of 1000 IU and 2000 IU Dose in Healthy Individuals.

BACKGROUND: Scientific studies point to a significant global vitamin D deficiency. The recommended dose of vitamin D for the adult population in Central Europe is 800-2000 IU/day. The aim of our study was to determine whether doses of 1000 IU or 2000 IU of vitamin D3 are adequate to achieve the sufficiency reference values of [25(OH)D]. METHODS: Seventy-two healthy volunteers, average age twenty-two, took part in the study. The study was conducted from October to March in order to eliminate intra-dermal vitamin D production. Vitamin D3 in an oleaginous mixture was used. The participants used either 1000 IU or 2000 IU/daily for two 60-day periods with a 30-day break. RESULTS: The dose of 1000 IU, taken for 60 days, increased vitamin D levels relatively little. Furthermore, serum vitamin D levels decreased in the 30 days following the cessation of supplementation. Taking 2000 IU daily led to a sharp increase in serum levels which plateaued 30 days after the subjects stopped using vitamin D3 drops. CONCLUSIONS: Both doses, taken daily, can help maintain adequate vitamin D levels during the winter months. A daily dose of 2000 IU, however, maintained the desired levels of vitamin D for a longer period.

iPSCs in Neurodegenerative Disorders: A Unique Platform for Clinical Research and Personalized Medicine.

In the past, several animal disease models were developed to study the molecular mechanism of neurological diseases and discover new therapies, but the lack of equivalent animal models has minimized the success rate. A number of critical issues remain unresolved, such as high costs for developing animal models, ethical issues, and lack of resemblance with human disease. Due to poor initial screening and assessment of the molecules, more than 90% of drugs fail during the final step of the human clinical trial. To overcome these limitations, a new approach has been developed based on induced pluripotent stem cells (iPSCs). The discovery of iPSCs has provided a new roadmap for clinical translation research and regeneration therapy. In this article, we discuss the potential role of patient-derived iPSCs in neurological diseases and their contribution to scientific and clinical research for developing disease models and for developing a roadmap for future medicine. The contribution of humaniPSCs in the most common neurodegenerative diseases (e.g., Parkinson's disease and Alzheimer's disease, diabetic neuropathy, stroke, and spinal cord injury) were examined and ranked as per their published literature on PUBMED. We have observed that Parkinson's disease scored highest, followed by Alzheimer's disease. Furthermore, we also explored recent advancements in the field of personalized medicine, such as the patient-on-a-chip concept, where iPSCs can be grown on 3D matrices inside microfluidic devices to create an in vitro disease model for personalized medicine.