Mean Value Of Optical Density Research Articles

From waste to resource: Effects of digested rotten potato supernatant on the growth, total biomass and nutrient composition of Chlorella vulgaris

A study was carried out to evaluate the growth performance of Chlorella vulgaris, a green microalga, in three different concentrations of digested rotten potato supernatant (DRPS) for 16 days. C. vulgaris was grown in 20 % (T1), 40 % (T2), and 60 % (T3) of the DRPS and at the same time in Bold Basal Medium (BBM) as a control (T4). A significantly highest cell density of C. vulgaris was found in T1 (192.83 ± 1.75 × 105 cells mL−1) in comparison to T2 (136.83 ± 5.58 × 105 cells mL−1), and T3 (99.11 ± 5.38 × 105 cells mL−1) (p < 0.001 for all comparisons) while the cell density at T1 (192.83 ± 1.75 × 105 cells mL−1) and T4 (180.907 ± 4.58 × 105 cells mL−1) did not differ significantly (p = 0.227). Moreover, the mean daily division rate of C. vulgaris was significantly higher in T1 (0.340 ± 0.001 divisions day−1) in comparison to other concentrations of DRPS (p < 0.001 for all comparisons). The maximum value of total biomass (1.07 ± 0.10 g L−1) was found in T1 which was statistically similar to those in T4 and T2. In addition, there was no significant difference between the mean maximum values of chlorophyll-a content and optical density of C. vulgaris in T1 and T4. The highest protein content of 42.67 ± 0.57 % was observed in T4 which was significantly higher than T1 (39.43 ± 1.67 %) (p = 0.027). It is also worth mentioning that there was no significant difference in the crude lipid content of the microalgae grown in T1 (10.06 ± 0.17 %) and T4 (9.88 ± 0.14 %) (p = 0.616). Hence, 20 % DRPS can be used as an alternative culture media of BBM for C. vulgaris with a broad aim to accelerate the sustainable advancement of microalgal production.

Combined low-dose isotretinoin and long-pulsed nd: YAG laser in the treatment of post-acne erythema

Post-acne erythema (PAE) is a bothering skin condition that emerges from inflammatory acne and persists after its resolution. It is characterized by telangiectasia and erythematous macules. the role of 1064-nm Nd: YAG when combined with low-dose isotretinoin in the acne erythema treatment. forty-eight PAE patients were involved in the study. They were divided into two groups; group (A) patients administering a low dose of oral isotretinoin (10 mg/day) and underwent a total of six two-week interval sessions of 1064 ND-YAG laser treatment, group (B) patients administering a low dose of oral isotretinoin (10 mg/day) only. All adverse effects experienced during the course of therapy were documented, and photos were taken before the start of the treatment and following the end of the treatment duration. Following the completion of the therapeutic intervention, a significant improvement in clinical condition was observed in both groups, with more improvement in group (A) compared to group (B) as evidenced by a notable improvement in the score on the Clinician Erythema Assessment Scale (CEAS) and also a significant decrease in the mean value of optical density of the erythema. combined 1064-nm Nd: YAG with low-dose isotretinoin may be an efficient and secure line in the PAE treatment. Also, the combined therapy had superior results when compared to low-dose isotretinoin alone.

Effect of Laser-assisted Subepithelial Keratectomy with Mitomycin C on Corneal Optical Density Measured with Confocal Microscopy.

The development of confocal microscopy allows one to obtain high-resolution corneal images like its optical density. Some studies have evaluated the optical density with Scheimpflug cameras in the early post-operative period after photorefractive keratectomy, but no studies have evaluated the long-term evolution of optical density after surface ablation when mitomycin C is used. This work aimed to study the changes in corneal optical density measured with confocal microscopy in eyes treated with laser-assisted subepithelial keratectomy (LASEK) and intraoperative mitomycin C (MMC) to correct myopia. A study of 24 consecutive myopic eyes that underwent LASEK with 0.02% MMC and a control group of 24 healthy nontreated eyes was performed. Optical density was measured using the images by the confocal microscopy of the Heidelberg Retina Tomograph II with the Rostock Cornea Module. An analysis of confocal microscopy images was performed using the ImageJ software to obtain the optical density, in gray-scale units (GSU). The optical density of the stromal bed was evaluated 3 months, 15 months, and 3 years after surgery and was compared with the optical density at the equivalent depth of the stroma in controls. The mean values of optical density for the LASEK group were 81.7 ± 9.7, 78.6 ± 11.7, and 73.6 ± 18.7 GSU at 3 months, 15 months, and 3 years, respectively, and it was 61.8 ± 8.2 GSU for the control group. A statistically higher optical density 3 and 15 months after LASEK with MMC was found compared with controls (P < .001). No significant difference was found in optical density at 3 years post-operatively. Our study suggests that, after LASEK with MMC, the anterior corneal stroma has a higher optical density at 3 and 15 months post-operatively, which gradually returns to normal values 3 years after surgery.

Evaluation of a Potential Bacteriophage Cocktail for the Control of Shiga-Toxin Producing Escherichia coli in Food.

Shiga-toxin producing Escherichia coli (STEC) are important foodborne pathogens involved in gastrointestinal diseases. Furthermore, the recurrent use of antibiotics to treat different bacterial infections in animals has increased the spread of antibiotic-resistant bacteria, including E. coli, in foods of animal origin. The use of bacteriophages for the control of these microorganisms is therefore regarded as a valid alternative, especially considering the numerous advantages (high specificity, self-replicating, self-limiting, harmless to humans, animals, and plants). This study aimed to isolate bacteriophages active on STEC strains and to set up a suspension of viral particles that can be potentially used to control STEC food contamination. Thirty-one STEC of different serogroups (O26; O157; O111; O113; O145; O23, O76, O86, O91, O103, O104, O121, O128, and O139) were investigated for their antibiotic resistance profile and sensitivity to phage attack. Ten percent of strains exhibited a high multi-resistance profile, whereas ampicillin was the most effective antibiotic by inhibiting 65% of tested bacteria. On the other side, a total of 20 phages were isolated from feces, sewage, and bedding material of cattle. The viral particles proved not to carry genes codifying Shiga-toxins and intimin. No STEC was resistant to all phages, although some strains revealed weak sensitivity by forming turbid plaques. Three different bacteriophages (forming the “cocktail”) were selected considering their different RAPD (Random Amplification of Polymorphic DNA) profiles and the absence of virulence-encoding genes and antibiotic-resistance genes. The lytic ability against STEC strains was investigated at different multiplicity of infection (MOI = 0.1, 1, and 10). Significant differences (p < 0.05) among mean values of optical density were observed by comparing results of experiments at different MOI and controls. An effective reduction of bacterial population was obtained in 81% of cases, with top performance when the highest MOI was applied. The efficacy of the phage cocktail was tested on fresh cucumbers. Results showed a reduction in pathogenic E. coli by 1.97–2.01 log CFU/g at 25°C and by 1.16–2.01 log CFU/g at 4°C during 24 h, suggesting that the formulated cocktail could have the potential to be used in bio controlling STEC different serogroups.

Susceptibility to Mumps Infections in Tikrit City: A Comparative Study

Background: Immunization has a promising future. We are entering a new era in which it is expected that the number of available vaccines will double. Immunization services are increasingly used to deliver other important health interventions, making them a strong pillar of health systems. There are still millions of people who do not benefit from the protection that vaccination provides. They are at risk of life-threatening illness every day. In Iraq there are still thousands of children who do not complete all their doses and hence not fully protected.Aim: This study aiming to illustrate the mumps immunological status in adults and children in Tikrit city.Materials and methods: A Cross-sectional prospective study conducted in Tikrit Teaching Hospital and Primary Health Care Centers. The study population included adults and children from both gender. The adult's population group is recruited from university students, while the children are recruited from 6th primary, 1st, 2nd and 3rd secondary schools. The sample size is 100 subjects in each adult and children groups [50 subject males and 50 females]. Thus a minimum of 200 subjects to be included in the study. A pre-designed questionnaire is used for gathering data from each individual included in the study. A verbal informed consent taken from each individual before enrolment in the program. Data on vaccination was taken directly from each individual or vaccination cards if available. ELISA was used for determination of IgG for mumps diseases in central research Laboratory and Tikrit Laboratory’s. The tests were performed according to manufacturer instructions.Results: The mean value of optical density was with predictive value for mumps antibodies concentration. The mumps antibodies mean serum value was lower in adult subjects as compared to child group. This finding indicated that immune response to mumps decreased with time and contributes to resurgence of mumps in community. Thus the frequency of mumps none immune status was higher in adults as compared to child. Additionally, mumps immune response with high titer was significantly lower in adults than in children. The high titer rate was two times more in children than in adults. These figures indicated that IgG mumps antibody concentration confirmed the possibility of immune reduction with age and explain the outbreak of the disease in vaccinated subjects. Thus the present study finding may gave an explanation for the high rate of reported cases in Iraq in 2016 as compared to previous years. However, the war conflict may act as another factor that disturbs the vaccination program performance

Inhibitory effect of jengkol leaf (Pithecellobium jiringa) extract to inhibit Candida albicans biofilm

Background: Candida albicans (C. albicans) are dimorphic fungi in oral cavity, considered not only as normal flora, but also as pathogens. C. albicans have an ability to grow biofilm, which has a thick layer of outer skin structure, called as extracellular matrix. Jengkol leaves (Pithecellobium jiringa) contain alkaloids, flavonoids, terpenoids, and lectins, which have an ability as antifungal agent Purpose: This study aimed to analyze the optimum dose of jengkol leaf extract as antibiofilm against C. albicans biofilms. Method: C. albicans were cultured on yeast peptone dextrosa (YPD) media in 96-well microtiter plate flat bottom plates. There were one control group (without treatment) and three treatment groups. The first treatment group was given jengkol leaf extract at a dose of 100 mg/ ml. The second treatment group was given jengkol leaf extract at a dose of 200 mg/ ml. And, the third treatment group was given jengkol leaf extract at a dose of 400 mg/ ml. Semi quantitative method was applied to determine C. albicans biofilmsis using Crystal Violet staining technique. The absorbance of the cells then was calculated using a spectrophotometer with a wavelength of 570 nm. Result: The mean value of optical density in the control group was 1.23. The mean value of optical density in the treatment group with a dose of 100 mg/ ml was 0.2. Meanwhile, the mean value of optical density in the treatment group with a dose of 200 mg/ ml was 0.2, and 0.21 in the treatment group with a dose of 400 mg/ ml. The results also showed that there were significant differences between the control group and all of the treatment groups (p&lt;0.05), but there was no significant difference between the treatment groups (p&gt;0.05). Conclusion: The optimum dose of jengkol leaf extract used as antibiofilm against C. albicans biofilms is 100 mg /ml with an inhibitory percentage of 83.7%.

Antimicrobial effect of ozonated water, sodium hypochlorite and chlorhexidine gluconate in primary molar root canals.

Objective:The aim was to determine the antimicrobial effect of ozonated water, ozonated water with ultrasonication, sodium hypochloride and chlorhexidine (CHX) in human primary root canals contaminated by Enterococcus faecalis (E. faecalis).Materials and Methods:Fifty-eight extracted human primary molar teeth were used. Crowns were cut off using a diamond saw under water-cooling. One hundred roots were obtained and mechanically prepared. The roots were then sterilized by autoclaving in water for 15 min at 121°C. All samples were contaminated with E. faecalis for 24 h and the root canals were randomly divided into five groups (n = 20). Group I: 25 mg/L of Ozonated water (O3aq), Group II: 25 mg/L of O3aq with ultrasonication, Group III: 2.5% Sodium hypochloride (NaOCl), Group IV: 2% CHX and Group V: Positive control. The canal of each specimen was irrigated for 4 min and positive control was untreated. All root canals were agitated with sterile saline solution. The saline solution was collected from canals with sterile paper points. For each specimen, the paper points were transposed to eppendorf vials containing 2 ml of brain heart infusion. According to bacterial proliferation, the mean values of optical density were achieved by ELİSA (Biotek EL ×800, Absorbance Microplate Reader, ABD) and the data were analyzed.Results:NaOCI, CHX and two types of O3aq were found statistically different than positive control group. NaOCI irrigation was found significantly most effective.Conclusions:NaOCl, CHX and O3aq applications provide antibacterial effect in vitro conditions in primary root canals.

Expression of C-kit Messenger Ribonucleic Acid and C-kit Protein in the Gallbladders in Guinea Pigs of High Cholesterol Diet

The c-kit protooncogene receptor and its ligand-stem cell factor regulating the proliferation and survival of interstitial cells of Cajal (ICCs) have been described. The aim of this study was to determine the expression of c-kit mRNA and c-kit protein in the gallbladders in guinea pigs of high cholesterol diet (HCD). The gallbladder samples from 16 guinea pigs of HCD and from 16 guinea pigs of standard diet (StD) were used for this study. Expression of c-kit mRNA was detected by reverse transcription polymerase chain reaction (RT-PCR), and expression of c-kit protein was detected by Western blot analysis. Serum total cholesterol (TC) (39 +/- 6 vs. 109 +/- 20 mg/dl), low density lipoprotein (LDL) cholesterol (24 +/- 4 vs. 71 +/- 10 mg/dl), high density lipoprotein (HDL) cholesterol (2.4 +/- 0.4 vs. 7.0 +/- 1.6 mg/dl), and triglyceride (TG) (58 +/- 8 vs. 118 +/- 23 mg/dl) concentrations were significantly higher in the HCD group than in the StD group of guinea pigs (P < 0.001, respectively). Decreased expression of c-kit mRNA was demonstrated in the HCD group compared with the StD group. The ratio of c-kit mRNA and GAPDH was 0.56 +/- 0.09 in controls and 0.50 +/- 0.07 in the HCD group (P = 0.033). C-kit protein expression significantly declined in the HCD group. The mean value of optical density was 129 +/- 25 in the StD group and 103 +/- 19 in the HCD group (P = 0.0009). The data indicate that the expression of c-kit mRNA and c-kit protein significantly decreased in the gallbladders in guinea pigs of HCD.

Effect of the proton motive force inhibitor carbonyl cyanide-m-chlorophenylhydrazone (CCCP) onPseudomonas aeruginosabiofilm development

Proton motive force (PMF) inhibition enhances the intracellular accumulation of autoinducers possibly interfering with biofilm formation. We evaluated the effect of the PMF inhibitor carbonyl cyanide-m-chlorophenylhydrazone (CCCP) on Pseudomonas aeruginosa biofilm development. Four epidemiologically unrelated P. aeruginosa isolates were studied. A MexAB-oprM overproducing strain was used as control. Expression of gene mexB was examined and biofilm formation after incubation with 0, 125 and 25 micromol l(-1) of CCCP was investigated. Mean values of optical density were analysed with one-way analysis of variance and t-test. Two isolates subexpressed mexB gene and only 25 micromol l(-1) of CCCP affected biofilm formation. Biofilms of the other two isolates and control strain PA140 exhibited significantly lower absorbance (P ranging from < 001 to < 0.05) with either 12.5 or 25 micromol l(-1) of CCCP. The PMF inhibitor CCCP effect was correlated with the expression of MexAB-OprM efflux system and found to compromise biofilm formation in P. aeruginosa. These data suggest that inhibition of PMF-dependent trasporters might decrease biofilm formation in P. aeruginosa.

Digital radiographic evaluation of optical density of porcelains used for fabrication of inlay/onlay prosthesis.

The purpose of this article was to compare the mean value of optical density of four porcelains commonly used for fabrication of inlay/onlay prostheses using direct digital radiograph. The sample consisted of 20 2-mm thick porcelain specimens (measured by digital pachymeter): Empress (Ivoclair), Simbios (Degussa), Vita Omega 900 and Vitadur Alpha (Vita Zahnfabrik). The values of optical density of the specimens were expressed in millimeters aluminum equivalent (mm eq Al). The samples were X-rayed using two charge coupled devices (CCD) - RVG (Trophy) - Visualix (Gendex) and a phosphor plate system – Digora (Soredex). The optical density reading was performed with Image Tool 1.28 in a total of 110 measurements. Statistical analysis showed that there were statistically significant differences in all materials studied (p < 0.05) regardless of the radiographic system used. The highest optical density value was found for Omega 900 (1.8988 mmeqAl – Visualix – Gendex) and the lowest for Vitadur Alpha (0.8647 – Visualix – Gendex). Thus, the material presenting the highest degree of optical density was Omega 900, Empress and Simbios presented intermediate optical density values, Vitadur Alpha presented the lowest value, and the optical density of porcelains was not influenced by the digital radiography systems.

Expression of c-kit messenger ribonucleic acid and c-kit protein in sigmoid colon of patients with slow transit constipation

The c-kit protooncogene receptor and its ligand stem cell factor regulate the proliferation and survival of germ cells as well as interstitial cells of Cajal (ICCs). Decreased numbers of ICCs and defects in its networks have been reported in the colon of patients with slow transit constipation (STC). However, little information about the c-kit messenger ribonucleic acid (mRNA) and protein expression in the constipated colon is available. The aim of this study was to determine whether the expression of c-kit mRNA and c-kit protein declined in the colon in STC. The sigmoid colonic samples from 12 patients with STC and from eight age-matched patients with non-obstructed colorectal cancer were used for this study. Expression of c-kit mRNA was detected by reverse transcriptase-polymerase chain reaction (RT-PCR), and expression of c-kit protein was detected by Western blot analysis. Decreased expression of c-kit mRNA was demonstrated in the STC group compared with the control group. The ratio of c-kit and beta-actin was 1.26+/-0.32 in controls and 1.17+/-0.41 in the STC group (U=0.500, P=0.029). c-kit protein expression significantly declined in the STC group. The mean value of optical density was 162.97+/-5.43 in the control group and 96.64+/-8.80 in the STC group (U=0.000, P=0.021). The data indicate that the expression of c-kit mRNA and c-kit protein significantly decreased in the colon of STC, suggesting that the c-kit signal pathway may play an important role in ICC reduction in STC.

The effect of vanillin (2%) on the growth of cariogenic bacteria (Streptococcus mutans and Lactobacillus)

This purpose of this study is to evaluate the effectiveness of vanillin (2%) alone and with Amber dentifrice on the cariogenic bacteria (Streptococcus mutans and Lactobacillus). The vanillin material was prepared in this study by the use of pure vanillin (2%). Two microorganisms were selected to examine the antimicrobial activity of the vanillin against dental caries. These microorganisms are Streptococcus mutans and Lactobacillus; both are isolated from the dental plaque on the carious surface and from saliva. For the assay the turbidity method was used as described by Abdul-Rahman (2001), using the mean value of optical density to record the growth of bacteria. This study showed that the vanillin (2%) alone and withdentifrice reported significantly less mean value of optical density for both bacteria compared with the control read. That means it is effective in controlling and preventing dental caries by reducing the growth of cariogenic microorganisms.

Remote-monitoring of the physiological-ecological status of crops. V. Texture analysis of canopy reflectance based on optical density in photographs and remote estimation of leaf chlorophyll concentration by spectral reflectances.

The objective of the present study was to obtain basic knowledge necessary for monitoring the physiological and ecological status of crops in fields by remote methods. The texture of reflectance within corn and soybean canopies was estimated from drum scanner analysis of color photographs, and compared with the actual distribution of leaf chlorophyll concentration (Chl) in the canopy. A model that estimated leaf Chl using multispectral remote sensing techniques was also examined. Actual Chl within the canopy had a near normal distribution (Fig. 2). However, the distribution of optical density in canopy photographs usually had a bimodal distribution pattern, which did not correspond with the actual distribution of Chl of leaves (Fig. 3A∼B, Fig. 4A∼B). The mean value of optical density was strongly affected not only by the color of each plant element but also by the degree of shading and angle of each leaf (Fig. 3C, Fig. 4C). The difference between the distribution mode and mean was reduced by avoiding the shaded parts (Fig. 4D). The spectral reflectance data from both crops revealed that wavelengths centered at 550 nm (Red) were most sensitive to the canopy Chl, while those in a near infrared region 750∼1, 050nm (NIR) were least sensitive. Statistically significant correlations were found between the ratio of NIR to Red reflectances (850nm/550nm) and leaf Chl for corn (0.68) and soybean (0.83). Differences between the regression lines for the two crops were attributed to leaf thickness (SLA)(Table 1, Fig. 5).