The relationship between vitamin D and the severity of COVID-19.

AIM: Vitamin D, which has immunomodulatory effect, can reduce risk of infections and concentrations of pro-inflammatory cytokines. The aim of this study was to investigate the relationship between the levels of vitamin D and severity of COVID-19. METHODS: A total of 204 patients with COVID-19 disease were enrolled in the study. All patients had viral pneumonia, which was confirmed with chest computer tomography. All cases were divided in two groups- mild (outpatients); and serious (inpatients)- according to their clinical and laboratory data. Serum vitamin D levels were measured by chemiluminescence method. RESULTS: Vitamin D deficiency was found in 41.7 % (n = 85) of cases and insufficiency was found in 46.0 % (n = 94), while in 12.3 % (n = 25) of cases normal vitamin D levels were found. The odds of having a serious clinical outcome were increased for vitamin D insufficiency patients 5.604 times (%95 CI:0.633-49.584) and for vitamin D deficiency patients 38.095 times (%95 CI:2.965-489.50) for each standard deviation decrease in serum 25(OH)D. CONCLUSION: Adequate levels of vitamin D could suppress inflammation and reduce the severity of COVID-19. Vitamin D supplementation may have an important role in decreasing the impact of the pandemic (Tab. 5, Fig. 2, Ref. 27).

Does rosmarinic acid treatment have protective role against sepsis-induced oxidative damage in Wistar Albino rats?

Reactive oxygen species are believed to be involved in the development of sepsis. Plant-derived phenolic compounds are thought to be possible therapeutic agents against sepsis because of their antioxidant properties. Rosmarinic acid (RA) is a phenolic compound commonly found in various plants, which has many biological activities including antioxidant activity. The aim of this study was to investigate the effects of RA on sepsis-induced DNA damage in the lymphocytes and liver and kidney cells of Wistar albino rats by alkaline comet assay with and without formamidopyrimidine DNA glycosylase protein. The oxidative stress parameters such as superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities and total glutathione (GSH) and malondialdehyde (MDA) levels in the liver and kidney tissues and an inflammatory cytokine, tumor necrosis factor α (TNF-α) level in plasma were also evaluated. It is found that DNA damage in the lymphocytes, livers, and kidneys of the RA-treated rats was significantly lower than that in the sepsis-induced rats. RA treatment also decreased the MDA levels and increased the GSH levels and SOD and GSH-Px activities in the livers and kidneys of the sepsis-induced rats. Plasma TNF-α level was found to be decreased in the RA-treated rats. It seems that RA might have a role in the attenuation of sepsis-induced oxidative damage not only by decreasing the DNA damage but also by increasing the antioxidant status and DNA repair capacity of the animals.

Aflatoxin levels in chronic hepatitis B patients with cirrhosis or hepatocellular carcinoma in Balikesir, Turkey.

Aflatoxins, the secondary metabolites produced by species of naturally occurring Aspergilli, are commonly found in food such as cereals, dried fruits and juice, wine, beer and spices. They are hepatotoxic and are well known human carcinogens based on evidence from human studies. Aflatoxins are an environmental risk factor for the development of hepatocellular carcinoma (HCC). Chronic hepatitis B-infected patients are at increased risk of cirrhosis, hepatic failure and liver cancer. This study was designed to determine the serum aflatoxin B1 (AFB1 ), aflatoxin B2 (AFB2 ), aflatoxin G1 (AFG1 ) and aflatoxin G2 (AFG2 ) concentrations using high-pressure liquid chromatography (HPLC) in hepatitis B-infected patients with or without cirrhosis and liver cancer, alongside healthy controls in Balikesir, Turkey. The mean AFB1 and total AF levels in patients without liver cancer and cirrhosis were significantly higher than healthy controls. The mean AFB1 and total AF levels in patients with chronic hepatitis B and HCC were significantly higher than infected patients with or without cirrhosis. These results suggest that patients with chronic hepatitis B who are exposed to AFs are at increased risk for developing HCC, which might be prevented by reducing consumption of contaminated foods.

In utero exposure to dicyclohexyl and di-n-hexyl phthalate possess genotoxic effects on testicular cells of male rats after birth in the comet and TUNEL assays.

Phthalates are diester derivatives of phthalic acid widely used in many commercial applications. The aim of this study is therefore to evaluate possible genotoxicity of di-n-hexyl phthalate (DHP) and dicyclohexyl phthalate (DCHP) at different concentrations using single-cell gel electrophoresis (comet) and terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end-labeling (TUNEL) assays in testes samples of male rat pups. DCHP and DHP in corn oil were administered to the pregnant rats by gavage at the doses of 0 (vehicle), 20, 100, and 500 mg kg(-1) day(-1) from gestational day 6 (GD6) to GD19. After delivery, male rats were allowed to grow until prepubertal, pubertal, and adulthood. At necropsy, the blood samples were collected from heart and were excised immediately. The apoptotic cells of prepubertal, pubertal, and adult testis were detected using TUNEL assay. The comet assay was performed on blood lymphocytes and testes samples of adult male rats. The comet assay results showed that tail length, tail intensity, olive tail moment (OTM), and percentage of DNA present in tail were higher when DHP content was increased. Judging from the values of OTM and percentage of DNA, DHP could significantly induce DNA breakage at doses of 100 and 500 mg kg(-1) day(-1) compared with the control group. An increase in TUNEL-positive cells of prepubertal, pubertal, and adult testicular cells was observed in the treated groups. In conclusion, prenatal exposure to DHP and DCHP may possess genotoxic risk to testicular cells of rats at all stages of development, even at adulthood.

Protective effects of resveratrol on sepsis-induced DNA damage in the lymphocytes of rats.

Sepsis, often initiated by an infection, is a state of disrupted inflammatory homeostasis. There is increasing evidence that oxidative stress has an important role in the development of sepsis-induced multiorgan failure. Resveratrol (RV) is a polyphenolic compound found in the skin of red fruits, such as mulberries and red grapes, and in peanuts. RV has been reported to have an antioxidant, antiproliferative, and anti-inflammatory properties in various models. It has also been found to inhibit the proliferation of a variety of human cancer cell lines, including breast, prostate, colon, pancreatic, and thyroid. This study has been undertaken to assess the role of RV on the sepsis-induced oxidative DNA damage in the lymphocytes of Wistar albino rats by the standard and formamidopyrimidine DNA glycosylase (Fpg)-modified comet assays. The parameters of tail length, tail intensity, and tail moment were evaluated for the determination of DNA damage. According to the study, the DNA damage was found to be significantly higher in the sepsis-induced rats when compared with the control rats (p < 0.05). The parameters were significantly decreased in the RV-treated sepsis-induced group when compared with the sepsis-induced group. The parameters in the sepsis-induced rats were found to be significantly higher in the Fpg-modified comet assay when compared with the standard comet assay (p < 0.05), and RV treatment decreases the DNA damage in the sepsis-induced rats, suggesting that the oxidative stress is likely to be responsible for DNA damage and RV might have a role in the prevention of sepsis-induced oxidative DNA damage.

Genotoxicity evaluation of dentine bonding agents by comet assay.

AIM: To evaluate the genotoxicity of four different adhesives, Clearfil SE Bond, SL Bond, i Bond and Clearfil Protect Bond and the primers of Clearfil SE Bond and Clearfil Protect Bond. METHODOLOGY: Genotoxicity assessment of the adhesives and primers was carried out in vitro in human lymphocytes at different elution concentrations, using the alkaline single-cell gel electrophoresis technique (comet assay). After the incubation of lymphocytes with varying volumes of the test agent, cells were embedded in a low-melting-point agarose suspension and then lysed in alkaline (pH>13) conditions. Electrophoresis was performed on the suspended lysed cells followed by visual analysis with staining of DNA. Fluorescence was than calculated to determine the extent of DNA damage using imaging software. Statistical comparison of the results was carried out by one-way analysis of variance (anova). RESULTS: A significant increase (P<0.001) compared to untreated controls in DNA damage was observed with 'Clearfil Protect Bond' and 'Clearfil SE Bond' primer in human lymphocytes at concentrations of 2.5 and 5.0 mg mL(-1). Clearfil Protect Bond and Clearfil SE Bond adhesives induced significant (P < 0.001) DNA damage only at the higher concentration of 5.0 mg mL(-1) . No significant increase in DNA damage was observed with SL Bond and i Bond. No significant DNA damage was observed with any dentine bonding agents at the lower concentration of 1.25 mg mL(-1) . CONCLUSIONS: 'Clearfil Protect Bond' and 'Clearfil SE Bond' primers/adhesives increased DNA damage in human peripheral lymphocytes in high doses.

Antioxidant activities of major thyme ingredients and lack of (oxidative) DNA damage in V79 Chinese hamster lung fibroblast cells at low levels of carvacrol and thymol.

The leafy parts of thyme and its essential oil have been used in foods for the flavour, aroma and preservation and also in folk medicines. In the present study the genotoxicity of thymol and carvacrol was examined using comet assay. In V79 Chinese hamster lung fibroblast cells treated with 1, 5, 25 microM thymol and carvacrol, only 25 microM thymol caused some clastogenic DNA damage. For detection of oxidative DNA damage, the comet assay with formamido pyrimidine glycosylase (Fpg) protein was used: When V79 cells were treated with 1, 5, 25 microM thymol and carvacrol and post-treated with Fpg enzyme, no significant increase of Fpg-sensitive sites was observed at all concentrations studied. Reactive oxygen species (ROS) generation decreased slightly in the presence of thymol (1-100 microM) and carvacrol (5 microM) between 1 and 4h, yet increased at the highest 100 microM concentration of carvacrol after 24h. Thymol and carvacrol displayed a concentration dependent antioxidant capacity, whilst gamma-terpinene which lacks a phenolic group did not show any antioxidant capacity in the trolox equivalent antioxidant capacity (TEAC) assay. The results of this study indicate a lack of clastogenic activity for thymol and carvacrol at biologically relevant concentrations, and a moderate antioxidant activity in vitro.

Effects of pesticides on human peripheral lymphocytes in vitro: induction of DNA damage.

Because of the widespread use of pesticides for domestic and industrial applications the evaluation of their genotoxic effects is of major concern to public health. Although various experimental data have provided evidence that pesticides can possess genotoxic properties in animals and in in vitro test systems after acute and chronic exposure, the information on the genotoxic effects of some of pesticides is limited and inconsistent. In the present study, the genotoxic potential of commonly used pesticides (i.e., dimethoate and methyl parathion from the organophosphate class, propoxur and pirimicarb from carbamates, and cypermethrin and permethrin from pyrethroids) have been evaluated. The genotoxic effects of these substances were examined using the single cell gel electrophoresis (comet) assay in freshly isolated human peripheral lymphocytes. The cells were incubated with 10, 50, 100 and 200 microg/ml concentrations of the test substances for 0.5 h at 37 degrees C and DNA damage was compared with that obtained in lymphocytes from the same donor not treated with substances. Hydrogen peroxide, 100 microM, was used as a positive control. Within the concentration ranges studied, no significant cytotoxic effects were observed. Dimethoate and methyl parathion at 100 and 200 microg/ml; propoxur at 50, 100 and 200 microg/ml, and pirimicarb, cypermethrin and permethrin at 200 microg/ml significantly increased DNA damage in human lymphocytes.

Influence of apple cultivars on inactivation of different strains of Escherichia coli O157:H7 in apple cider by UV irradiation.

This study examined the effect of different apple cultivars upon the UV inactivation of Escherichia coli O157:H7 strains within unfiltered apple cider. Apple cider was prepared from eight different apple cultivars, inoculated with approximately 10(6) to 10(7) CFU of three strains of E. coli O157:H7 per ml (933, ATCC 43889, and ATCC 43895), and exposed to 14 mJ of UV irradiation per cm(2). Bacterial populations for treated and untreated samples were then enumerated by using nonselective media. E. coli O157:H7 ATCC 43889 showed the most sensitivity to this disinfection process with an average 6.63-log reduction compared to an average log reduction of 5.93 for both strains 933 and ATCC 43895. The highest log reduction seen, 7.19, occurred for strain ATCC 43889 in Rome cider. The same cider produced the lowest log reductions: 5.33 and 5.25 for strains 933 and ATCC 43895, respectively. Among the apple cultivars, an average log reduction range of 5.78 (Red Delicious) to 6.74 (Empire) was observed, with two statistically significant (alpha < or = 0.05) log reduction groups represented. Within the paired cultivar-strain analysis, five of eight ciders showed statistically significant (alpha < or = 0.05) differences in at least two of the E. coli strains used. Comparison of log reductions among the E. coli strains to the cider parameters of (o)Brix, pH, and malic acid content failed to show any statistically significant relationship (R(2) > or = 0.95). However, the results of this study indicate that regardless of the apple cultivar used, a minimum 5-log reduction is achieved for all of the strains of E. coli O157:H7 tested.

Alterations of neutrophil functions in foundry and pottery workers.

To assess the immune competence of workers occupationally exposed to mainly silica, neutrophil functions such as the chemotactic and oxidative burst activity in foundry and pottery workers were evaluated. The chemotactic activity was examined in 22 foundry and 10 pottery workers and oxidative burst activity of neutrophils were determined in 22 foundry and 6 pottery workers. Healthy subjects of comparable age, sex, and smoking habits and with no history of silica exposure were used as the control groups. Chemotaxis was carried out in Boyden chambers using Zymosan activated serum as chemotactic stimulus. Oxidative burst activity was measured using nitroblue tetrazolium (NBT) dye reduction test. Both neutrophil functions were significantly reduced in silica-exposed foundry and pottery workers (p < 0.001) compared to controls suggesting that human chronic exposure mainly to silica and other chemicals originated from foundry and pottery settings may diminish neutrophil functions in humans.

Effects of pesticide exposure on serum immunoglobulin and complement levels.

Serum immunoglobulins (IgG, IgA and IgM), C3 and C4 complement protein levels were examined in the male workers of the municipality who routinely applied pesticides for at least one year, and compared to healthy male controls in order to determine whether immune alterations were evident in the pesticide-exposed workers. Pyrethroids were the most commonly used pesticides for the last 3 years. Serum immunoglobulins and complement levels were measured by turbidimetry. Serum IgG, IgA, IgM and C3 complement levels were found to be unchanged when compared to controls whereas a significant decrease was observed in serum C4 complement levels of the workers.

A study on geno- and immunotoxicological effects of subacute propoxur and pirimicarb exposure in rats.

A 28-day oral exposure with 8.51, 3.40, and 0.851 mg/kg propoxur (PR) and 4.67, 1.87, and 0.467 mg/kg pirimicarb (PI) was performed in male Wistar rats, and the occurrence of numerical and structural chromosome aberrations and the changes in certain immune function parameters (plaque-forming cell (PFC) assay, delayed-type hypersensitivity reaction) and in some basic toxicological (body weight gain and weights of brain, thymus, lung, heart, liver, spleen, kidneys, adrenals, and popliteal lymph node) and hematological (white blood cells, red blood cells, hematocrit (Ht), mean cell volume of red blood cells (MCV) cell content of the femoral bone marrow) parameters were investigated. The high dose of PR increased the relative liver weight and the cell content of femoral bone marrow, and all three doses increased Ht and MCV. The applied doses of PI decreased the relative adrenal weight in a dose-dependent manner, and its highest dose increased the relative liver weight. Among the immune function parameters tested, PFC content of the spleen was decreased by high-dose PR and elevated by high-dose PI, whereas the maximum and the time course of the delayed-type hypersensitivity reaction showed no changes in this dose range. In the genotoxicological investigations only the high PR dose increased the number of numerical, but not the structural, chromosome aberrations. In addition to the changes in relative adrenal weight following PI treatment, the PFC assay showed the highest sensitivity for detection of the 4-week exposure with these carbamates. On the basis of our results, the immunotoxicological approach seems to have the same (PR) or higher (PI) sensitivity in early detection of the repeated low-dose exposure by these carbamates compared to the genotoxicological approach.

Immunotoxicological investigations on rats treated subacutely with dimethoate, As3+ and Hg2+ in combination.

Effects of combined exposure with dimethoate (DM), HgCl2 (Hg), and NaAsO2 (As) were investigated following a 28 - day oral exposure in male Wistar rats. In preliminary experiments, the LOEL (Lowest Observed Effect Level) and NOEL (Non Observed Effect Level) doses of the substances were determined using the same experimental system [determination of body weight gain, organ weights of brain, thymus, heart, lung, kidneys, adrenals, spleen, testicles, popliteal lymph node, white blood cell (WBC) and red blood cell (RBC) count, haematocrit (Ht), mean cell volume (MCV) of RBCs, cell content of the femoral bone marrow, IgM-plaque forming cell (PFC) content of the spleen, delayed type hypersensitivity (DTH) reaction] and animal strain. In the combination studies, LOEL dose of DM (28.2 mg/kg) was combined with NOEL doses of the heavy metals ( HgCl2 = 0.40 mg/kg, NaAsO2 = 3.33 mg/kg), and vice versa (DM = 7.04 mg/kg, HgCl2 = 3.20 mg/kg, NaAsO2 = 13.3 mg/kg). In the DM-Hg combinations, significant alterations were found versus the corresponding high- dose internal control in the body weight gain, relative liver and kidney weights, and in the PFC response. When DM was combined with As, interactions were indicated by changes of relative liver weight, MCV value, and the PFC content of the spleen. These results support the theory that the interactions between pesticides and heavy metals may modify the toxic effects of the single substances, and may also change the functional detection limits of the exposure. The changes in the functional detection limits, if they occur, can lead to false-positive and false-negative results in human epidemiological studies.

Detection of the effects of repeated dose combined propoxur and heavy metal exposure by measurement of certain toxicological, haematological and immune function parameters in rats.

In the present study, an immunotoxicity test system, containing general toxicological (body weight gain, organ weights), haematological (WBC,RBC, Ht, mean cell volume of the RBCs, cell content of the femoral bone marrow), and immune function (PFC assay, DTH reaction) investigations, was used for detection the effects of a 4 weeks repeated low dose combined oral exposure of male Wistar rats with propoxur and the heavy metals arsenic or mercury. Two doses of the compounds were used: a higher one (the lowest dose which resulted in significant change of at least one parameter examined in previous dose-effect experiments), and a lower one (the highest dose which proved to be non-effective). The applied doses were: 8.51 and 0.851 mg kg(-1) of propoxur, 13.3 and 3.33 mg kg(-1) of NaAsO(2), and 3.20 and 0.40 mg kg(-1) of HgCl(2). In the combination treatment, the high dose of propoxur was combined with the low dose of arsenic or mercury, and the high doses of each heavy metals were combined with the low dose of propoxur. The main finding of this study was that some of the combinations significantly altered the relative weight of liver, adrenals and kidneys, related to both the untreated and the high dose internal control. Among the immune functions examined, only the PFC content of the spleen showed a trend of changes in certain combinations versus the corresponding high dose control. According to the present results, combined exposure with propoxur and the heavy metals examined can modify the detection limit of the single compounds and/or may alter their toxic effects.

Immunotoxicological investigation of subacute combined exposure by permethrin and the heavy metals arsenic(III) and mercury(II) in rats.

Effects of combined 28 days of oral exposure to the insecticide Permethrin (Pe), alone or in combination with arsenic-III (As) or Hg-II (Hg), were investigated on certain toxicological (body weight, organ weights), haematological (white blood cell (WBC) and red blood cell (RBC) counts, haematocrit (Ht), mean cell volume (MCV), cell content of the femoral bone marrow) and immune function (IgM-PFC, delayed-type hypersensitivity (DTH) reaction) parameters of male Wistar rats. Immunotoxic (H = high) and NOEL (L = low) doses of the three substances were determined in preliminary experiments under identical experimental conditions. In the present study, the immunotoxic dose of Pe (126 mg/kg) was combined with the NOEL dose of As (3.33 mg/kg) or Hg (0.40 mg/kg), and the NOEL dose of Pe (12.6 mg/kg) with the immunotoxic dose of As (13.3 mg/kg) or Hg (3.20 mg/kg). A separate group of animals, treated with the appropriate high dose component only, was used as internal control. Significant interactions were observed in the liver weight of the animals treated with Pe(H)-As(L) or As(H)-Pe(L), in the cell content of the femoral bone marrow in case of Pe(H)-As(L) and Pe(H)-Hg(L) combinations, as well as in the number of PFCs formed from 10(6) spleen cells in the Pe(H)-As(L) and in the maximum of DTH reaction in the Hg(H)-Pe(L) combination. The results show that combined exposures by the investigated substances modify the toxic (including immunotoxic) effects of the single compounds. These findings rise the probability that the interactions observed can also be present in human situations altering the health hazard of this three chemicals.

Cloning and heterologous expression of xylanase from Pichia stipitis in Escherichia coli.

AIMS: The main goal of this study was to characterize the xylanase (xynA) gene from Pichia stipitis NRRL Y-11543. METHODS AND RESULTS: The xylanase gene was cloned into pUC19 in Escherichia coli DH5alphaF' and selected by growth on RBB-xylan. All functional clones contained a recombinant plasmid with an insert of 2.4 kbp, as determined by restriction mapping. The nucleotide sequence of the P. stipitis xylanase gene consisted of 1146 bp and encoded a protein of 381 amino acids with a molecular weight of 43 649 Da. The sequence contained a putative 20-amino acid N-terminal signal sequence and four N-linked glycosylation sites. The Km values for non-glycosylated and glycosylated xylanases were 1.4 mg ml-1 and 4.2 mg ml-1, respectively, and Vmax values were 0.8 and 0.082 micromol min-1 mg-1 protein, respectively. CONCLUSION: Xylanase, a rarely found enzyme in yeast species, has been characterized in detail. SIGNIFICANCE AND IMPACT OF THE STUDY: The results of this study can be used to develop better xylanase-utilizing yeast strains.

Molecular differentiation of Lactococcus lactis subspecies lactis and cremoris strains by ribotyping and site specific-PCR.

Twenty-five strains of Lactococcus lactis subspecies lactis and subspecies cremoris obtained from dairy industry and environmental collections were examined by 16S RNA automated ribotyping profiles and site-specific PCR (S-PCR). By automated ribotyping, the majority of strains were classified in accordance with phenotypic characterization, with the exception of one lactis (220) and two cremoris (BO32 and 140) strains. A complete differentiation of subspecies lactis and cremoris in agreement with conventional phenotypic methods was achieved by S-PCR with a set of site-specific primer pairs (PR1, RM4, and F3) designed particularly from a deletion region found in subspecies cremoris, but not in lactis. Therefore, S-PCR with primers (PR1, RM4, and F3) is a rapid and very sensitive method for the distinction of lactis and cremoris subspecies in dairy production.

A rare case: mosaic trisomy 22.

A 9-year-old female child of healthy parents (mother: 43 years, father: 44 years) was referred to our center because of severe mental retardation. While pedigree analysis was not contributory, two older sibs were normal and healthy. Physical examination revealed facial dysmorphism, microcephaly and hyperflexibility of all joints. Her chromosome constitution showed a mosaic pattern; mos 46,XX[98]/47,XX,+22[2]. So skin biopsy was performed and mosaic trisomy 22 was confirmed with FISH analysis (46,XX[73]/47,XX,+22[27]). Physical features of this case seemed consistent with her mosaic constitution. This report would be a demonstrative example to show the significant contribution of FISH in states of mosaicism.

Effects of lead on immune parameters in occupationally exposed workers.

BACKGROUND: To assess the immune competence of workers occupationally exposed to lead, several subsets of peripheral lymphocytes, i.e., T, TCD4(+), TCD8(+), B, NK cells, serum immunoglobulin and complement protein concentrations, chemotaxis, and intracellular killing activity of neutrophils of 25 male storage battery workers have been analyzed and compared to 25 healthy males with no history of lead exposure. RESULTS: The results of this study which indicated that industrial exposure to lead resulting in group mean blood lead concentrations of 75 +/- 18 microg/dl are associated with a significant depression of: T helper lymphocytes, Ig G, Ig M and C3, C4 complement levels, chemotaxis, and random migration of neutrophils. No correlation was found between the duration of exposure and the altered immune parameters. CONCLUSIONS: The immune system can be a target for lead toxicity and elimination of lead hazard in working places is necessary.