Piezosurgery versus conventional rotary surgery for impacted third molars: A randomised, split-mouth, clinical pilot trial

BACKGROUND

Few studies have compared the effects of piezosurgery and conventional rotary surgery for impacted wisdom teeth on the quality of life. Among these studies, the inclusion parameters and evaluation methods have varied.

MATERIAL AND METHODS

This study aimed to compare the effects of piezosurgery and conventional rotary instruments on the quality of life using a standardised method. Patients with bilateral and symmetric mandibular impacted wisdom teeth were included based on the Winter and Pell-Gregory scale and Yuasa difficulty index criteria. The primary objective was to assess the effects of the methods on the quality of life using the Oral Health Impact Profile-14 questionnaire. Secondary objectives included comparisons of swelling, trismus, pain, and total operative times. The study was conducted between October 2021 and March 2022. The clinical trial protocol was recorded in the United States National Library of Medicine clinical trial registry (NCT05545553).

RESULTS

We enrolled 20 patients (40 wisdom teeth) and found that the removal of impacted teeth using the piezosurgery method positively affected the quality of life and considerably improved swelling, trismus, and pain scores. However, piezosurgery may affect postoperative morbidities such as increased total operative times.

CONCLUSIONS

Piezosurgery appears to have advantages over conventional rotary surgery for impacted wisdom tooth extraction in terms of quality of life and postoperative symptoms. However, further research should investigate potential drawbacks and confirm these findings.

Comparison of immunogenicity for Sinovac-CoronaVac vaccine vs. natural infection during cancer treatment

OBJECTIVE

Efficacy of the COVID-19 vaccines in cancer patients, especially during their active treatment, are lacking. Most of the studies in the literature compared the immunity in cancer patients with a cross-sectional cohort or retrospectively. Our study investigated Sinovac-CoronaVac COVID-19 vaccine immunogenicity and compared it with natural COVID-19 disease in cancer patients during their cancer therapy.

PATIENTS AND METHODS

A total of 111 patients with cancer and who are on active treatment were included in the study. This is a single-center study and was designed prospectively. Two group of patients were included in the study, natural disease and vaccinated group.

RESULTS

A total of 111 patients were included in the study, 34 of whom had natural COVID-19 disease. Antibody levels following the first dose vaccine were 0.4 (0-1.9) U/ml while after the second dose of vaccine were 2.6 (1.0-7.25) U/ml. Immunogenicity levels were 82.4% in the natural disease group and 75.8% in the vaccinated group after the second shot of the vaccine. Immunogenicity rate was significantly higher in non-chemotherapy (receiving immunotehrapy/targeted therapy or biologic agent) group compared to chemotherapy drug (92.9% vs. 63.3%, p=0.004). There was a difference between the antibody levels following the first and second vaccination [median (IQR): 0.3 (0-1.0) and 3.3 (2.0-6.7), p=0.001, respectively].

CONCLUSIONS

The present study revealed that the Sinovac-CoronaVac vaccine showed an acceptable immunogenicity following two shots in cancer patients who were receiving active systemic therapy. On the other hand, natural disease immunogenicity was higher than vaccinated group.

The significance of a novel inflammatory biomarker, presepsin, in predicting disease prognosis in patients with COVID-19

OBJECTIVE

This study aims at determining the significance of a novel inflammatory biomarker, presepsin, in predicting disease prognosis in patients with COVID-19.

PATIENTS AND METHODS

This retrospective study was concluded at the University Hospital between April and August 2020. The study involved 88 COVID-19 patients (48 men and 40 women). The patients were categorized into two groups: the patients admitted to the COVID-19 clinic, described as the moderate COVID-19 patients (Group-1; n=44), and those admitted to the internal medicine outpatient clinic, who were the mild COVID-19 patients (Group-2; n=44). The groups were compared using inflammatory markers: presepsin, C-Reactive Protein to Albumin Ratio, Neutrophil to Lymphocyte Ratio, and procalcitonin.

RESULTS

Serum presepsin levels (195.29 vs. 52.12 pg/ml) were significantly higher in the Group-1 compared to the Group-2 (p=0.001). The gender distribution and average age were similar in both groups (p > 0.05). While ferritin, lactate dehydrogenase, D-Dimer, platelet lymphocyte ratio, C-Reactive Protein to Albumin Ratio (p=0.001), erythrocyte sedimentation ratio, C-Reactive Protein and presepsin were significantly higher in the Group-1 compared to Group-2 (p<0.05), while hemoglobin and lymphocyte were significantly lower in the Group-1 than in Group-2 (p<0.05).

CONCLUSIONS

Serum presepsin levels were found to be significantly higher in moderate clinical group COVID-19 patients compared to mild group. Presepsin, a new inflammatory biomarker, may be useful in predicting the prognosis and early treatment of COVID-19 infection.

The role of neutrophil albumin ratio in predicting the stage of non-small cell lung cancer

OBJECTIVE

Inflammation forms the basis of cancer development and progression. It causes changes in complete blood count parameters, such as neutrophil counts. Low albumin levels are associated with poor prognosis in cancer patients. We aimed to investigate the association between neutrophil to albumin ratio (NAR) and the stage of non-small cell lung cancer (NSCLC).

PATIENTS AND METHODS

257 NSCLC patients (24 females and 198 males) were included in the study. Patients were divided into two groups. Group 1 (n=61) included patients with early stage cancer (stage 1 and 2), while group 2  (n=196) included those with advanced stage cancer (stage 3 and 4). Demographic data, neutrophil, lymphocyte, platelet, white blood cell counts (WBC), C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), ferritin and albumin levels at the time of diagnosis were recorded. The NAR of 2 groups were compared.

RESULTS

There were no significant differences between the lymphocyte count (2.0 vs. 2.0 103/mm3) and platelet count (291 vs. 311 103/mm3) of the two groups (p > 0.05). ESR (38.8 vs. 57.5 mm/h), CRP (158 vs. 57 mg/l), ferritin (85 vs. 261 ng/ml), WBC count (8.6 vs. 10.6 103/mm3), neutrophil count (5.6 vs. 7.5 103/mm3), albumin values (2.9 vs. 3.7 gr/dl), and (p < 0.05) NAR levels (1.6 vs. 2.3) (p < 0.05) were significantly higher in group 2.

CONCLUSIONS

NAR can be used in predicting the stage of NSCLC.

Evaluating the effect of tumor size and sidedness on prognosis in stage 2 colon cancer: a retrospective population study

OBJECTIVE

In this study, we aimed to evaluate the effect of tumor size and tumor sidedness on prognosis in patients with stage 2 colon cancer.

PATIENTS AND METHODS

Data of 501 patients diagnosed with stage 2 colon cancer were evaluated retrospectively. It was evaluated whether the patients' age, gender, tumor differentiation, tumor node metastasis (TNM) stage, overall survival rate, and disease-free survival rate had any correlation with horizontal tumor diameter and tumor sidedness. In the ROC analysis performed to determine the cut-off value for the tumor diameter, which we think will predict survival, no significant results were obtained with maximum sensitivity and specificity. Therefore, the median value of the tumor diameter, which is 5 cm, was accepted as the cut-off value.  Kaplan-Meier method and Cox regression analysis were used for survival analysis and determination of prognostic factors.

RESULTS

When the patients were evaluated in terms of tumor localization, 189 (37.7%) patients had right colon tumors and 312 (62.3%) patients had left colon tumors. There was no statistically significant difference in terms of disease-free survival and overall survival according to tumor localization. When the patients were analyzed by dividing them into two groups according to the horizontal tumor size (<5 cm and ≥5 cm), no statistically significant difference was found between the groups in terms of disease-free survival (DFS) and overall survival (OS) p=0.085, p=0.699, respectively.

CONCLUSIONS

Our results suggest that the management of patients with stage 2 colon cancer requires a better understanding of tumor biology rather than features such as tumor size and localization.

Salt and nitrogen amendment and optimization for cellulase and xylanase production using dilute acid hydrolysate of distillers' dried grains with solubles (DDGS) as the feedstock

Distillers' dried grains with solubles (DDGS) is a by-product of dry-mill corn ethanol production comprising a high nutritional value due to residual fiber, protein, and lipid contents. The fiber content of DDGS is high enough to be considered a valuable source for the production of hydrolytic enzymes, such as cellulase and xylanases, which can be used for hydrolysis of lignocellulosic feedstock during ethanol production. The DDGS-based medium prepared after acid hydrolysis provides adequate sugars for enzyme production, while additional macronutrients, such as salts and nitrogen sources, can enhance the enzyme production. Therefore, this study was undertaken to evaluate the effect of salts (KH₂PO₄, CaCl₂·2H₂O, MgSO₄·7H₂O, FeSO₄·7H₂O, CoCl₂·6H₂O, and MnSO₄·H₂O), peptone, and yeast extract on enzyme secretion by four different Aspergillus niger strains and to optimize the nitrogen source for maximum enzyme production. Yeast extract improved the cellulase production (0.38 IU/ml) for A. niger (NRRL 1956) as compared to peptone (0.29 IU/ml). However, maximum cellulase productions of 0.42 IU/ml and 0.45 IU/ml were obtained by A. niger (NRRL 330) and A. niger (NRRL 567), respectively, in presence of ammonium sulfate. The optimized nitrogen amounts resulted in a significant increase in the cellulase production from 0.174 to 0.63 IU/ml on day 9 of the fermentation with A. niger (NRRL 330). The composite model improved both cellulase and xylanase production. In conclusion, the optimization of all three nitrogen sources improved both cellulase and xylanase production in the DDGS-based media.

Development of bioactive solid support for immobilized Lactobacillus casei biofilms and the production of lactic acid

Polypropylene was modified to contain chitosan and evaluate its ability to generate Lactobacillus casei biofilms and their lactic acid production. Biofilm formation was carried out in either rich or minimal media. The chitosan-modified polypropylene harbored ~ 37% more cells than the control polypropylene. The biofilms from the chitosan-modified polypropylene grown in rich medium produced ~ 2 times more lactic acid after 72 h of incubation than the control suspended cells. There was no significant difference in the production of lactic acid after 72 h by L. casei biofilms on the chitosan-modified polypropylene grown in minimal media as compared with cells in suspension after 48 h and 72 h of incubation. Infrared spectroscopy confirmed higher deposition of nutrients and biomass on the chitosan-modified polypropylene as compared to the chitosan-free polypropylene. Electron and atomic force microscopy confirmed thicker biofilms when rich media were used to grow them as compared to minimal medium.

Pulsed Ultraviolet Light Decontamination of Meat Conveyor Surfaces

Contact with continuous belt conveyors during processing results in opportunities for pathogenic and spoilage microorganisms to contaminate meat products. The objective of this project is to investigate the germicidal response on the surface of food-grade conveyor belt materials treated with pulsed ultraviolet (PUV) light. Four conveyor belt types including: a stainless-steel chain-link belt, a polytetrafluoroethylene (PTFE)-coated fabric belt, a solid pliable polymer belt, and a rigid-linked polymer belt, were evaluated for the inactivation of Escherichia coli K12-NSR strain and lactic acid bacteria (LAB). Prior to bacterial inoculation, samples were classified as soiled or unsoiled, based on the presence or absence of pork intramuscular fluid on the surfaces of the conveyor samples. Using a variable speed conveyor, equipped with a Xenon flashlamp positioned 10-cm above the surface, each belt sample was exposed to PUV light at three fixed conveyor speeds: 3.05, 15.24, and 30.48 cm/sec, resulting in a total energy exposure of 3.31, 0.66 and 0.33 J/cm², respectively. For samples inoculated with E. coli K12-NSR, the surface condition (soiled or unsoiled) by treatment interaction was significant for microbial inactivation on the surface of the rigid polymer linked belt (P < 0.05). For samples inoculated with the LAB cocktail, the same interaction was significant for the PTFE-coated fabric belt and the solid pliable polymer belt (P < 0.05). Microbial reduction ranged from 0.74 to 5.04 log₁₀ CFU/cm² for E. coli K12-NSR and 0.63 to 4.61 Log₁₀ CFU/cm² for LAB for the evaluated treatment parameters. The results of this project demonstrate that PUV light is an effective means of decontamination for conveyor belts during food processing.

Pulsed Ultraviolet Light Treatment of Chicken Parts

With increasing production and consumption of chicken, it is appropriate to investigate the functionality and effectiveness of microbial reduction interventions and the qualitative effects they have on food. The effectiveness of pulsed ultraviolet (PUV) light applied to chicken on a moving conveyor was evaluated for inactivation of Escherichia coli on the surface of raw boneless/skinless (B/S) chicken breasts, B/S chicken thighs, and bone-in/skin-on chicken thighs. The conveyor height (distance from the flashlamp) and speed were set to deliver total energy fluences of 5, 10, 20, and 30 J/cm2 to the surface of the products. The product type by energy fluence interaction was significant (P = 0.015) for microbial reduction of E. coli. Exposure to PUV light for 5 and 30 J/cm2 resulted in Log10 reductions of 0.29 and 1.04 for B/S breasts, 0.34 and 0.94 for B/S thighs, and 0.10 and 0.62 for bone-in/skin-on thighs, respectively. Lipid oxidation and changes in color of chicken samples were evaluated after 30 J/cm2 of PUV light treatment. Lipid oxidation was measured at 0, 24, 48, and 120 h after the treatment. PUV light treatment did not produce significant (P &gt; 0.05) changes in lipid oxidation values for each product type. International Commission on Illumination L*, a*, and b* parameters were used to report lightness and color of samples before and after treatment for B/S breasts and thighs and bone-in/skin-on thighs. Color parameters were not significantly (P &gt; 0.05) affected by PUV light treatments. In conclusion, this study indicates that PUV light applied to the surface of raw chicken parts on a moving conveyor is an effective surface antimicrobial treatment while inducing minimal change in quality of the product over a 5-d storage period under aerobic conditions.

The efficacy of pulsed ultraviolet light processing for table and hatching eggs

In the United States, every year an average of 287.1 eggs are consumed per person, and over 14.1 billion eggs are set in hatchery incubators to produce chicks destined for the egg and meat bird industries. By reducing the microbial load on eggs, food-borne-associated outbreaks can be reduced while good chick health is maintained. Pulsed ultraviolet (PUV) light system delivers an energy-intense broad spectrum (100-1,100 nm) pulse derived from a xenon flashlamp. In recent years, PUV light has been shown to reduce microbial pathogens on the surface of shell eggs by using a static PUV light system. In this study, shell eggs were surface inoculated with Escherichia coli or Enterococcus faecium and treated with PUV light using a modified egg candling conveyor that provided complete rotation of eggs under a flashlamp. Pulsed UV light treatment inactivated both microbial strains, with greater energy resulting in a greater germicidal response (P < 0.05). Treatments of 1.0, 2.4, 3.1, and 4.9 J/cm2 resulted in microbial reductions (Log10 CFU/cm2) of 3.83, 4.26, 4.28, and 4.62 for E. coli and 2.04, 3.12, 3.11, and 3.82 for E. faecium, respectively. This study also evaluated the effects of PUV light treatment of hatching eggs (commercial Leghorn hybrids) on both embryo and chick growth parameters. Using the same system, 4 replicates of 125 fertile eggs per rep were treated with 0 (control), 4.9, 24.4, or 48.8 J/cm2 of PUV light. After processing, eggs were placed in a commercial incubator under normal incubation conditions. There was no significant effect of the PUV light treatment on percent fertility, hatchability, or hatch (P > 0.05). Furthermore, there were no significant effects on posthatch observations, including livability and average bird weight at hatch or at 42 d of age (P > 0.05). In conclusion, this study supports the application of PUV light as an effective antimicrobial intervention for both table and hatching eggs.

Nonlinear modulation of periodic waves in the cylindrical Gardner equation

The propagation of dispersive shock waves (DSWs) is investigated in the cylindrical Gardner (cG) equation, which is obtained by employing a similarity reduction to the two-space one-time (2+1) dimensional Gardner-Kadomtsev-Petviashvili (Gardner-KP) equation. We consider the steplike initial condition along a parabolic front. Then, the cG-Whitham modulation system, which is a description of DSW evolution in the cG equation, in terms of appropriate Riemann-type variables is derived. Our study is supported by numerical simulations. The comparison is given between the direct numerical solution of the cG equation and the DSW solution obtained from the numerical solution of the Whitham system. According to this comparison, a good agreement is found between the solutions.

What Can We Estimate From Fatality and Infectious Case Data Using the Susceptible-Infected-Removed (SIR) Model? A Case Study of Covid-19 Pandemic

The rapidly spreading Covid-19 that affected almost all countries, was first reported at the end of 2019. As a consequence of its highly infectious nature, countries all over the world have imposed extremely strict measures to control its spread. Since the earliest stages of this major pandemic, academics have done a huge amount of research in order to understand the disease, develop medication, vaccines and tests, and model its spread. Among these studies, a great deal of effort has been invested in the estimation of epidemic parameters in the early stage, for the countries affected by Covid-19, hence to predict the course of the epidemic but the variability of the controls over the course of the epidemic complicated the modeling processes. In this article, the determination of the basic reproduction number, the mean duration of the infectious period, the estimation of the timing of the peak of the epidemic wave is discussed using early phase data. Daily case reports and daily fatalities for China, South Korea, France, Germany, Italy, Spain, Iran, Turkey, the United Kingdom and the United States over the period January 22, 2020-April 18, 2020 are evaluated using the Susceptible-Infected-Removed (SIR) model. For each country, the SIR models fitting cumulative infective case data within 5% error are analyzed. It is observed that the basic reproduction number and the mean duration of the infectious period can be estimated only in cases where the spread of the epidemic is over (for China and South Korea in the present case). Nevertheless, it is shown that the timing of the maximum and timings of the inflection points of the proportion of infected individuals can be robustly estimated from the normalized data. The validation of the estimates by comparing the predictions with actual data has shown that the predictions were realized for all countries except USA, as long as lock-down measures were retained.

Inactivation of Escherichia coli K-12 in Liquid Egg White By a Flow-through Pulsed Uv Light Treatment System

ABSTRACT

Unpasteurized liquid egg can be contaminated with pathogenic microorganisms and may cause foodborne outbreaks. Thus, it is essential to decontaminate the liquid egg to ensure food safety. Pulsed UV light is one of the emerging technologies for food decontamination in recent years. This static treatment system has been studied previously in our laboratory. However, continuous processing using a flow-through treatment system needs to be evaluated for potential commercial applications. Therefore, in this study, a flow-through treatment system of pulsed UV light was evaluated and optimized for inactivation of Escherichia coli K12NSR for liquid egg white decontamination. Treatment factors including flow rate (40 to 80 mL/min), number of passes (one to three passes), and distance from the sample to the pulsed UV light strobe (5 to 13 cm) were optimized using response surface methodology. This methodology suggested three passes with 40 mL/min flow rate and a 5-cm distance as the optimum conditions. The model was then validated for the maximum reduction of E. coli K12NSR, which was measured as 1.57 log CFU/mL at the optimal conditions. The energy doses of the pulsed UV light and temperature changes of the liquid egg white during the treatment were measured. Furthermore, several quality parameters were assessed at the optimum treatment conditions to determine the impact of the flow-through pulsed UV processing on the quality of liquid egg white. The results showed significant differences in pH, lipid oxidation, turbidity, and color between control and pulsed UV light-treated samples (P < 0.05). However, there was no significant difference in foaming ability or foam stability between pulsed UV light-treated samples and the control. Overall, this study demonstrated the potential of flow-through pulsed UV light to decontaminate liquid egg white, but further research is needed for optimal enhancement.

HIGHLIGHTS

Decontamination of Chicken Thigh Meat by Pulsed Ultraviolet Light

Foodborne illness outbreaks associated with chicken can be reduced with effective decontamination interventions. The effectiveness of pulsed ultraviolet (PUV) light for destruction of Salmonella, E. coli, and Campylobacter on the surface of chicken thigh meat was investigated. Chicken thighs were inoculated to 6 to 7 log10 CFU/cm2 before exposure to PUV light for each of the above-mentioned pathogens. Treatment variables included the distance from the quartz window of the PUV light (8 and 13 cm) and treatment time (0, 5, 15, 30, and 45 s). Comparison of treated samples to control (0 s) samples allowed for quantification of microbial reduction due to PUV light treatment. Microbial reduction on lean surface chicken thighs (P < 0.05) with increasing duration of PUV light exposure for E. coli, Campylobacter, and Salmonella. Exposure to PUV light for 5 and 45 s on lean surface thighs resulted in log10 CFU/cm2 reductions of 1.22 and 2.02 for E. coli, 1.45 and 2.09 for Campylobacter, and 1.55 and 2.42 for Salmonella, respectively. Pulsed UV light exposure for 5 and 45 s on skin surface thighs resulted in log10 reductions of 1.19 and 1.96 for E. coli; 1.08 and 1.85 for Campylobacter, and 0.90 and 1.82 for Salmonella, respectively. Results indicate that PUV light is effective for reductions of bacterial populations on the surface of raw chicken meat.

Inactivation of Staphylococcus aureus and Escherichia coli O157:H7 on fresh kashar cheese with pulsed ultraviolet light

Pulsed ultraviolet light is a potential postprocessing decontamination method which is able to reduce pathogens on solid food surfaces. Cheese surfaces may become easily contaminated with pathogens due to improper handling or contact with unhygienic surfaces during or after processing. In this study, the effects of pulsed ultraviolet light on Staphylococcus aureus and Escherichia coli O157:H7 on fresh kashar cheese were investigated. Pulsed ultraviolet light was applied to kashar cheese for different times (5, 15, 30, 45, 60 s) at 5, 8, and 13 cm from the quartz window in a pulsed ultraviolet light system. Based on the inactivation level, time, and visual evaluation, the most favorable treatment was determined as the 45 s-13 cm treatment (∼44 J/cm²). This treatment yielded about 1.62 and 3.02 log₁₀ reductions (cfu/cm²) for S. aureus and E. coli O157:H7, respectively, while did not alter (p>0.05) the pH, lipid oxidation, and moisture content of kashar cheese, except the color parameters. When 0.5 cm thick kashar cheese was treated with pulsed ultraviolet light at a distance of 5 cm from the quartz window, the highest energy transmittance was found to be about 9.16%. These findings demonstrate that pulsed ultraviolet light has the potential for postprocessing decontamination of semi-hard cheese surfaces.

Biofilm reactors as a promising method for vitamin K (menaquinone-7) production

Menaquinone-7 (MK-7) is the most potent subtype of vitamin K with extraordinarily high half-life in the circulatory system. Therefore, MK-7 plays a critical role in promoting human wellbeing today. Studies on MK-7 every year show more and more magnificent benefits of it in preventing cardiovascular diseases and osteoporosis to battling cancer cells, Alzheimer's and Parkinson's diseases. Thus, it needs to be supplemented to daily diet for accumulative and long-term benefits. Chemical synthesis of MK-7 produces a significant cis-isomer form of it, which has no biological activity. Fortunately, due to its key role in electron transfer in bacteria, trans-MK-7 is biosynthesized by especially Gram-positive strains mainly Bacillus genus. Concordantly, MK-7 could be produced via solid or liquid state fermentation strategies. In either regime, when static fermentation is applied in the absence of agitation and aeration, operational issues arise such as heat and mass transfer inefficiencies. Thus, scaling up the process becomes a challenge. On the other hand, studies have indicated that biofilm and pellicle formation that occur in static fermentations are key characteristics for extracellular MK-7 secretion. Therefore, this review covers the most recent discoveries of the therapeutic properties of MK-7 and optimization attempts at increasing its biosynthesis in different media compositions and effective growth parameters as well as the cutting-edge use of biofilm reactors where B. subtilis cells have the infrastructures to form mature biofilm formations on plastic composite supports. Biofilm reactors therefore can provide robust extracellular MK-7 secretion while simultaneously enduring high agitation and aeration rates, which then address the scale-up and operational issues associated with static fermentation strategies.

Optimization of dilute sulfuric acid, aqueous ammonia, and steam explosion as the pretreatments steps for distillers' dried grains with solubles as a potential fermentation feedstock

Distillers' dried grains with solubles (DDGS) is the by-product of bioethanol production from starch-rich grains through dry-mill fermentation. In this study, dilute sulfuric acid hydrolysis, aqueous ammonia, and steam explosion as the pre-treatment methods were optimized. The central composite response surface methodology (RSM) design was used for optimization of dilute acid pretreatment, aqueous ammonia pretreatment. The steam explosion trials were evaluated. The results show that the dilute acid pretreatment at 121 °C is the most effective way of obtaining simple fermentable sugars (0.382 g/g DDGS). The levels of furfural and HMF was also 5.2 mg/g DDGS) and 1.6 mg/g DDGS, respectively, in the dilute sulfuric acid pretreated DDGS. On the other hand, maximum sugar yield for ammonia pretreatment was 0.129 g/g DDGS and 0.055 g/g DDGS for the steam pretreatment, while no significant amounts of furfural and HMF were observed for these two pretreatment methods.

Enhanced Vitamin K (Menaquinone-7) Production by Bacillus subtilis natto in Biofilm Reactors by Optimization of Glucose-based Medium

BACKGROUND

Benefits of vitamin K have been reported by many studies recently, due to its ability to reduce the risk of cardiovascular diseases and its potential benefits against osteoporosis. Specifically, menaquinone-7 (MK-7), being the most potent form of vitamin K, has definitely received most of the attention. Currently, solid or static liquid fermentation strategies are utilized for industrial production of MK-7 by Bacillus strains. However, these strategies face fundamental operational and scale-up issues as well as intense pellicle and biofilm formations which is problematic in static liquid fermentation, due to heat and mass transfer inefficiencies they create.

OBJECTIVE

The purpose of this study was to demonstrate that biofilm reactors will overcome the issues associated with suspended cell reactors when using Bacillus strains to produce MK-7. The expectation is that the use of biofilm reactors will result in a significant increase in the production of MK-7.

METHOD

Vitamin K production by Bacillus subtilis natto when grown in a biofilm reactor was evaluated at various concentrations of the three major nutrients, glucose, yeast extract and casein. The data was analyzed using response surface methodology (RSM).

RESULTS

The maximum concentration of MK-7 in the biofilm reactors was 20.5±0.5 mg/L, which was a 344 % increase when compared to the amount produced in suspended-cell reactors containing the same optimum media composition.

CONCLUSION

These results demonstrate the potential of utilizing biofilm reactors for MK-7 production on an industrial scale.

Cyclosiloxane polymer bearing dynamic boronic acid: synthesis and bottom-up nanocoating

Boronic acid-containing polycyclosiloxane showed unique self-assembly nanofilm formation (6 nm film thickness) on various substrates and provided film-based metal ion sensor capability through dynamic covalent bonding.

Effects of medium components in a glycerol-based medium on vitamin K (menaquinone-7) production by Bacillus subtilis natto in biofilm reactors

Menaquinone-7 (MK-7) as the most important form of Vitamin K has been reported to have miraculous benefits such as preventing cardiovascular diseases and osteoporosis along with antitumor effects. Therefore, there have been numerous studies in the past decades to improve MK-7 production via microbial fermentation. Unfortunately, both solid and liquid state fermentation strategies that are utilized for MK-7 production, face fundamental operational and scale-up issues as well as intense heat and mass transfer problems during fermentation. In this regard, biofilm reactors seem to be a practical solution to overcome these issues and enhance the production in agitated liquid fermentation. Therefore, this study was undertaken to utilize biofilm reactors in investigating and optimizing different media components in a glycerol-based medium. Using response surface methodology, the effects of glycerol, yeast extract, and soytone were studied in the fermentation medium on MK-7 production in biofilm reactor. With a composition of 48.2 g/L of glycerol, 8.1 g/L of yeast extracts, 13.6 g/L of soytone and 0.06 g/L of K₂HPO₄, MK-7 concentrations could reach 14.7 ± 1.4 mg/L in biofilm reactors, which was 57% higher compared to the MK-7 concentration achieved in suspended-cell reactors under similar conditions, while glycerol was depleted by the end of the fifth day in biofilm reactors, but glycerol was never depleted in suspended-cell reactors. Evidently, biofilm reactors present a reliable strategy to address the operational issues that occur during MK-7 biosynthesis on an industrial scale production.

Implementation of fed-batch strategies for vitamin K (menaquinone-7) production by Bacillus subtilis natto in biofilm reactors

Recent studies show the essential health benefits associated with vitamin K, especially menaquinone-7 (MK-7). These benefits include reducing risks of cardiovascular diseases, osteoporosis, and even cancer. However, MK-7 production on an industrial level is only possible through bacterial fermentation and also current static fermentation strategies are not potent enough with difficulties to scale up. Biofilm reactors, however, may be a practical alternative. Biofilm reactors provide a controlled environment for the microorganisms to form mature and robust biofilms that enable them to produce value-added products with enhanced efficiencies. In this study, fed-batch addition of glucose and glycerol were investigated to the base media in biofilm reactors, as carbon source addition seemed crucial in batch fermentations. Results indicated that fed-batch strategies can be significantly effective in glucose-based medium, increasing the end-product concentrations to 28.7 ± 0.3 mg/L of MK-7 which was 2.3 fold higher than the level produced in suspended-cell bioreactors and renders the biofilm reactors as a potential replacement for static fermentation strategies. Moreover, morphological changes of B. subtilis were tracked during the 12-day long fermentation runs and finally, SEM investigations confirmed significant biofilm and extracellular matrices formed on the plastic composite support (PCS) in the biofilm reactors. In conclusion, biofilm reactors especially with fed-batch fermentation regimes seem to be an effective tool for MK-7 production at industrial scales.

[Effects of Vibrax (Mechanical Vibrations) on the Arterial Blood Gases of Patients in the Intensive Care Unit after Cardiac Surgery]

OBJECTIVE

Respiratory physiotherapy is an integral part of the care of patients in intensive care units (ICU) after cardiac surgery. One of the most commonly used techniques in ICU to prevent pulmonary complications are mechanical vibrations, which can be applied with a tool called Vibrax.The aim of this study was to investigate the effects of Vibrax (mechanical vibrations) on the arterial blood gases of patients in ICU during the 1. or 2. day after cardiac surgery.

METHODS

A randomized controlled pilot study was conducted with 23 patients. The participants of the control group (CG) received a cardiovascular training with mobilization to the edge of the bed and active breathing exercises. On the patients of the intervention group (IG) additionally Vibrax was applied for 5 minutes. As primary outcome parameter the PaO2/FiO2 ratio was measured.

RESULTS

In the CG no significant changes over time were observed (p ≥ 0.06). The IG showed a significant (p = 0.009) increase in the PaO2/FiO2 ratio from before the physiotherapy intervention (M = 296.52, SE = 34.94 mmHg) to 60 minutes after completion of the physiotherapy intervention (M = 331.39, SE = 48.14 mmHg). There was no significant difference between the CG and IG at any measuring time (p ≥ 0.09).

CONCLUSION

The results of this pilot study indicate that the application of Vibrax has positive effects on the arterial blood gases of patients in ICU on the 1. or 2. day after cardiac surgery. But whether the effects are clinically relevant could not be clarified.

Short Communications

Congenital agenesis of the right lobe of the liver is a rare anomaly. In a case report the diagnosis was made by computed tomography. A retro- or suprahepatic location of the gallbladder and compensatory hypertrophy of the left liver lobe and/or caudate lobe may give support to the diagnosis. Before diagnosing congenital agenesis of the lobe, lobar atrophy due to cirrhosis, cholangiocarcinoma or any other predisposing conditions should be eliminated.

Diffusion Weighted MRI of Primary Pituitary Abscess

Pituitary abscess is a rarely seen entity that can lead to serious neuroendocrine disorders or even be fatal if not diagnosed or treated correctly. Preoperative diagnosis plays an important role in planning the operation and treatment strategies. This report describes the diagnostic value of diffusion-weighted imaging (DWI) in addition to conventional magnetic resonance imaging (MRI) of primary pituitary abscess formation caused by Klebsiella ozaenea in a 33-year-old man.

MR Spectroscopy Findings in Lhermitte-Duclos Disease

Lhermitte-Duclos disease (LDD) is a rare hamartomatous focal or diffuse enlargement of the cerebellum with unclear etiology. The characteristic magnetic resonance imaging (MRI) appearance consists of a non-enhancing mass in the cerebellar hemisphere with a striated pattern. The slow growing behavior of this benign lesion is characteristic. In a few reports on magnetic resonance spectroscopy (MRS) findings in LDD, a decreased level of N-acetyl aspartate, increased level of lactate and near normal level of choline were described. The information obtained from MRS is useful to confirm the relatively benign hamartomatous nature of the lesion. This paper reports a case of LDD and describes the MRI and MRS findings.

Strain selection and medium optimization for glucoamylase production from industrial potato waste by Aspergillus niger

BACKGROUND

Glucoamylase is one of the most common enzymes used in the food industry to break down starch into its monomers. Glucoamylase production and its activity are highly dependent on medium composition. Starch is well known as a glucoamylase inducer, and utilization of industrial starchy potato waste is an inexpensive way of improving glucoamylase production. Since glucoamylase production is highly dependent on medium composition, in this study medium optimization for glucoamylase production was considered to enhance glucoamylase activity.

RESULTS

Among the evaluated microbial species, Aspergillus niger van Tieghem was found to be the best glucoamylase-producing fungus. The Plackett-Burman design was used to screen various medium ingredients, and malt extract, FeSO4 .7H2 O and CaCl2 ·2H2 O were found to have significant effects on glucoamylase production. Finally, malt extract, FeSO4 .7H2 O and CaCl2 .2H2 O were optimized by using a central composite design of response surface methodology. The results showed that the optimal medium composition for A. niger van Tieghem was 50 g L(-1) industrial waste potato mash supplemented with 51.82 g L(-1) malt extract, 9.27 g L(-1) CaCl2 ·2H2 O and 0.50 g L(-1) FeSO4 .7H2 O.

CONCLUSION

At the end of optimization, glucoamylase activity and glucose production were improved 126% and 98% compared to only industrial waste potato mash basal medium; 274.4 U mL(-1) glucoamylase activity and 41.7 g L(-1) glucose levels were achieved, respectively. © 2015 Society of Chemical Industry.

Radiation exposure of patient and surgeon in minimally invasive kidney stone surgery

OBJECTIVE

Percutaneous nephrolithotomy (PNL) and retrograde intrarenal surgery (RIRS) are the standard treatments used in the endoscopic treatment of kidney stones depending on the location and the size of the stone. The purpose of the study was to show the radiation exposure difference between the minimally invasive techniques by synchronously measuring the amount of radiation the patients and the surgeon received in each session, which makes our study unique.

MATERIALS AND METHODS

This is a prospective study which included 20 patients who underwent PNL, and 45 patients who underwent RIRS in our clinic between June 2014 and October 2014. The surgeries were assessed by dividing them into three steps: step 1: the access sheath or ureter catheter placement, step 2: lithotripsy and collection of fragments, and step 3: DJ catheter or re-entry tube insertion.

RESULTS

For the PNL and RIRS groups, mean stone sizes were 30mm (range 16-60), and 12mm (range 7-35); mean fluoroscopy times were 337s (range 200-679), and 37s (range 7-351); and total radiation exposures were 142mBq (44.7 to 221), and 4.4mBq (0.2 to 30) respectively. Fluoroscopy times and radiation exposures at each step were found to be higher in the PNL group compared to the RIRS group. When assessed in itself, the fluoroscopy time and radiation exposure were stable in RIRS, and the radiation exposure was the highest in step 1 and the lowest in step 3 in PNL. When assessed for the 19 PNL patients and the 12 RIRS patients who had stone sizes≥2cm, the fluoroscopy time in step 1, and the radiation exposure in steps 1 and 2 were found to be higher in the PNL group than the RIRS group (P<0.001).

CONCLUSION

Although there is need for more prospective randomized studies, RIRS appears to be a viable alternate for PNL because it has short fluoroscopy time and the radiation exposure is low in every step.

LEVEL OF EVIDENCE

4.

The prevalence of developmental delay among children aged 3-60 months in Izmir, Turkey

BACKGROUNDS

Developmental delay is defined as delays in speech and language development, motor development, social-emotional development and cognitive development. On a global scale, the prevalence estimations in paediatric population range between 5% and 15%. However, no prevalence studies on developmental delay have been conducted in primary care in Turkey. The aim of this study was to determine the prevalence of developmental delay among children aged 3-60 months in Izmir.

METHODS

This cross-sectional, descriptive study involved 1514 children aged 3-60 months, who were at 12 primary health centres for various reasons in Izmir between 1 November 2013 and 31 January 2014. The questionnaire and age-specific Turkish version of the Ages and Stages Questionnaires were applied to mothers via face-to-face interview.

RESULTS

The prevalence of developmental delay was 6.4% (95% confidence interval 5.2-7.7). The prevalence for age groups varied between 3.3% and 12.1%. Significant associations were found between developmental delay and maternal age, maternal/paternal education, socio-economic level of the family and the presence of consanguineous marriage.

CONCLUSIONS

Identifying developmental delay in children earlier by a validated, reliable, parent-completed questionnaire like Ages and Stages Questionnaires and detecting risk factors for delay are crucial for primary care where their growth and development are monitored. Identifying developmental delay and early referral to rehabilitation services may help improve children's quality of life.

Enhanced Bio-Ethanol Production from Industrial Potato Waste by Statistical Medium Optimization

Industrial wastes are of great interest as a substrate in production of value-added products to reduce cost, while managing the waste economically and environmentally. Bio-ethanol production from industrial wastes has gained attention because of its abundance, availability, and rich carbon and nitrogen content. In this study, industrial potato waste was used as a carbon source and a medium was optimized for ethanol production by using statistical designs. The effect of various medium components on ethanol production was evaluated. Yeast extract, malt extract, and MgSO₄·7H₂O showed significantly positive effects, whereas KH₂PO₄ and CaCl₂·2H₂O had a significantly negative effect (p-value < 0.05). Using response surface methodology, a medium consisting of 40.4 g/L (dry basis) industrial waste potato, 50 g/L malt extract, and 4.84 g/L MgSO₄·7H₂O was found optimal and yielded 24.6 g/L ethanol at 30 °C, 150 rpm, and 48 h of fermentation. In conclusion, this study demonstrated that industrial potato waste can be used effectively to enhance bioethanol production.

Recent advances for the production and recovery methods of lysozyme

Lysozyme is an antimicrobial peptide with a high enzymatic activity and positive charges. Therefore, it has applications in food and pharmaceutical industries as an antimicrobial agent. Lysozyme is ubiquitous in both animal and plant kingdoms. Currently, egg-white lysozyme is the most commercially available form of lysozyme. The main concerns of egg-white lysozyme are high recovery cost, low activity and most importantly the immunological problems to some people. Therefore, human lysozyme production has gained importance in recent years. Scientists have developed transgenic plants, animals and microorganisms that can produce human lysozyme. Out of these, microbial production has advantages for commercial productions, because high production levels are achievable in a relatively short time. It has been reported that fermentation parameters, such as pH, temperature, aeration, are key factors to increase the effectiveness of the human lysozyme production. Moreover, purification of the lysozyme from the fermentation broth needs to be optimized for the economical production. In conclusion, this review paper covers the mechanism of lysozyme, its sources, production methods and recovery of lysozyme.

Enhanced Aspergillus ficuum phytase production in fed-batch and continuous fermentations in the presence of talcum microparticles

This study aimed to enhance Aspergillus ficuum phytase production in fed-batch and continuous fermentations with addition of talcum microparticles. Phytase activity almost doubled in fed-batch and continuous fermentations by addition of 15 g/l of talcum compared to the control. Effect of talcum on fungal morphology was also shown that addition of talcum provided smaller fungal pellets and more homogenized fermentation broth compared to the control. Average fungal pellet radius decreased from 500 to 100 µm by addition of 15 g/l of talcum in the bioreactors. Also, 15 g/l talcum addition increased phytase productivity and optimum dilution rate in the continuous fermentations from 0.293 to 0.621 U/ml/h and from 0.09 to 0.1/h, respectively, compared to control.

Microparticle-enhanced Aspergillus ficuum phytase production and evaluation of fungal morphology in submerged fermentation

Phytase can be used in animal's diets to increase the absorption of several divalent ions, amino acids and proteins and to decrease the excessive phosphorus release in manure to prevent negative effects on the environment. This study aimed to enhance the current submerged fungal phytase productions with a novel fermentation technique by evaluating the effect of the various microparticles on Aspergillus ficuum phytase production. It was observed that microparticles prevented bulk fungal pellet growth, decreased average fungal pellet size and significantly increased phytase activity in the submerged fermentation. Microbial structure imaging results showed that the average fungal pellet radius decreased from 800 to 500 and 200 µm by addition of 15 g/L aluminum oxide and talcum, respectively, in shake-flask fermentation. Also, addition of 15 g/L of talcum and aluminum oxide increased phytase activity to 2.01 and 2.93 U/ml, respectively, compared to control (1.02 U/ml) in shake-flask fermentation. Additionally, phytase activity reached 6.49 U/ml within 96 h of fermentation with the addition of 15 g/L of talcum, whereas the maximum phytase activity was only 3.45 U/ml at 120 h of fermentation for the control in the 1-L working volume bioreactors. In conclusion, microparticles significantly increased fungal phytase activity and production yield compared to control fermentation.

Facile synthesis of cyclosiloxane-based polymers for hybrid film formation

A one-pot facile synthesis of cyclosiloxane-based hybrid polymers based on hydrosilylation reaction and their network polymer film formation via self-crosslinking by hydrolysis/condensation reactions are reported.

Decontamination of hard cheeses by pulsed UV light

Cheese is a ready-to-eat food that may be contaminated on the surface by undesirable spoilage and pathogenic microorganisms during production, packaging, and postpackaging processes. Penicillium roqueforti is commonly found on cheese surfaces at refrigeration temperatures and is one of the most common spoilage fungal species. Consumption of cheese contaminated with Listeria monocytogenes can result in foodborne listeriosis. Therefore, cheese should be decontaminated at postprocessing stages. Pulsed UV light is a nonthermal method for food preservation that involves the use of intense short pulses to ensure microbial decontamination on the surface of foods or packaging materials. In this study, the efficacy of pulsed UV light for inactivation of P. roqueforti and L. monocytogenes inoculated onto packaged and unpackaged hard cheeses was investigated. Treatment times and the distance from the UV strobe were evaluated to determine optimum treatment conditions. Packaged and unpackaged cheeses were treated at distances of 5, 8, and 13 cm for up to 60 s. For P. roqueforti, maximum reduction after 40 s at 5 cm was 1.32 log CFU/cm(2) on unpackaged cheese and 1.24 log CFU/cm(2) on packaged cheese. Reductions of L. monocytogenes under the same treatment conditions were about 2.9 and 2.8 log CFU/cm(2) on packaged and unpackaged cheeses, respectively. The temperature changes and total energy increases were directly proportional to treatment time and inversely proportional to distance between the UV lamp and the samples. The changes in color and lipid oxidation were determined at mild (5 s at 13 cm), moderate (30 s at 8 cm), and extreme (40 s at 5 cm) treatments. The color and chemical quality of cheeses were not significantly different after mild treatments (P > 0.05). The mechanical properties of the plastic packaging material (polypropylene) also were evaluated after mild, moderate, and extreme treatments. A decreasing trend was noted for elastic modulus; however, no significant differences were found between untreated samples and those given mild and moderate treatments (P > 0.05). Overall, these results indicate that pulsed UV light can inactivate P. roqueforti and L. monocytogenes on the surface of hard cheeses.