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The aim of this work was to fabricate microporous poly(trimethylene carbonate) (PTMC) vascular structures by stereolithography (SLA) for applications in tissue engineering and organ models. Leachable CaCO3 particles with an average size of 0.56 &mu, m were used as porogens. Composites of photocrosslinkable PTMC and CaCO3 particles were cast on glass plates, crosslinked by ultraviolet light treatment and leached in watery HCl solutions. In order to obtain interconnected pore structures, the PTMC/CaCO3 composites had to contain at least 30 vol % CaCO3. Leached PTMC films had porosities ranging from 33% to 71% and a pore size of around 0.5 &mu, m. The mechanical properties of the microporous PTMC films matched with those of natural blood vessels. Resins based on PTMC/CaCO3 composites with 45 vol % CaCO3 particles were formulated and successfully used to build vascular structures of various shapes and sizes by SLA. The intrinsic permeabilities of the microporous PTMC films and vascular structures were at least one order of magnitude higher than reported for the extracellular matrix, indicating no mass transfer limitations in the case of cell seeding.

Strawberry (Fragaria x ananassa) is a highly perishable product and rarely to be kept for more than 7 days. Cold chain system is the only methods apply in Malaysia strawberry industry to prolong the shelf life and preserve the quality of strawberry. UV light treatment proved to be effective in inhibit microbial loads and delay ripening process of fruit products where short wavelength (254 nm) ultraviolet-C was proved in keeping the freshness and quality of fruits or vegetables. This experiment was conducted to determine the effect of UV-C irradiation on extending shelf life and to determine the optimum radiation intensity of UV-C treatment on postharvest quality of treated strawberry. A total of 399 of strawberries cv. Festival were harvested in red colour with maturity stage of >80 – 85% from Cameron Highlands’s strawberry farm. The strawberries were exposed to different doses (0, 0.5, 0.6, 0.7, 0.8, 0.9 and 1.0 kJ/m2) of ultraviolet-C (254nm, UV-C) radiation. The treated strawberries were randomly placed in the polystyrene trays and stored in the dark chilling room at -5Co for 9 days. The significant differences were found when the highest level of dosage was applied. UV-C treated strawberries with the highest doses (1.0 kJ/mo) are significantly firmer (0.557N), higher total soluble solids content (7.5 oBrix) and ascorbic acid contain (0.518mg/ml) on day 9 (p

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 > 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 > 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.

Uvod: Fototerapija je metoda zdravljenja zmerne do hude oblike luskavice, ki temelji na uporabi pozitivnih učinkov ultravijolične svetlobe. S pravilno zdravstveno obravnavo in skrbno zdravstveno nego ter rednim sledenjem napredku zdravljenja je možno v relativno kratkem času doseči remisijo bolezni. Namen zaključnega dela je raziskati učinkovitost in varnost fototerapije pri zdravljenju luskavice ter ukrepe za lajšanje neželenih učinkov zdravljenja. Metode: Uporabljena je bila deskriptivna metoda dela, za sistematični pregled in analizo podatkov o opredeljeni temi smo iskali znanstvene in strokovne članke v angleškem jeziku v podatkovnih bazah CINAHL, MEDLINE, PubMed, ScienceDirect in Google Scholar. Iskanje smo omejili na literaturo publicirano v letih od 2009 do 2019. Rezultati: V raziskavo smo zajeli 14 študij. Raziskava je potrdila, da je fototerapija varna in učinkovita metoda zdravljenja luskavice. Pri tem so prisotni minimalni neželeni učinki, ki se najpogosteje kažejo kot eritem, srbečica, bolečina, ob večletni uporabi fototerapije pa se lahko pojavi pigmentacija kože, prezgodnje staranje kože, katarakta in zvišana možnost za nastanek melanoma. Zgoraj naštete neželene učinke je mogoče preprečevati in lajšati z natančnim upoštevanjem navodil. Razprava in sklep: Najučinkovitejša vrsta fototerapije je PUVA, saj je za očiščenje kože potrebno manj obiskov terapij kot pri ostalih vrstah fototerapij, obdobje remisije bolezni je daljše in zagotavlja nižjo stopnjo ponovljivosti. Vendar zdravljenje s PUVA fototerapijo povzroča več neželenih učinkov kot druge vrste fototerapij. Na podlagi raziskave smo spoznali, da je ozkopasovna UVB fototerapija najvarnejša. Introduction: Phototherapy is a method to treat moderate to severe forms of psoriasis using the positive effect of ultraviolet light. With a proper medical treatment, careful nursing care and regular monitoring of treatment progress, it is possible to achieve disease remission in a relatively short time. The aim of thesis was to investigate efficiency and safety of phototherapy treatment of psoriasis and to research measures to alleviate the side effects of treatment. Methods: A descriptive method was used to systematically review and analyse data. We searched for scientific articles in English in the CINAHL, MEDLINE, PubMed, ScienceDirect and Google Scholar database. Search was restricted to literature published between 2009 and 2019. Results: In total 14 studies were included in the research. The study confirmed that phototherapy is a safe and effective method of treating psoriasis. Minimal side effects are present, most commonly manifesting as erythema, itching and pain. After multiple years of phototherapy treatments, it can lead to pigmentary disorder, premature skin aging, cataracts and can increase risk of melanoma. Side effects can be relieved by following the medical care instructions. Discussion and conclusions: The most effective type of phototherapy is PUVA, since skin cleaning requires less treatments than other phototherapy types, the disease remission period is longer and provides a lower relapse rate. PUVA causes more side effects than other types of phototherapy. Narrow-band UVB phototherapy has been recognized as one of the safest.

BACKGROUND Pathogen reduction technologies (PRTs) are considered for the implementation of safer platelet (PLT) transfusion. PRT treatment involves the addition of a photosensitizer to a blood component followed by ultraviolet (UV) light irradiation. However, the effects of PRT treatment on PLT thrombus formation and thrombus stability have not been satisfactorily clarified. STUDY DESIGN AND METHODS Leukoreduced PLT concentrates (PCs) were treated with riboflavin and UV light (Mirasol PRT). PLT thrombus formation on collagen was evaluated by the microchannel method, by which the total amount of PLTs deposited was measured as indices of thrombus formation and thrombus stability. Using a cone-plate shear-induced PLT aggregometer, PLT reactivity in blood flow was examined in a wide range of shear stresses of 6 to 108 dyn/cm2 . RESULTS There was no significant difference in surface coverage between PRT-treated PLTs and control PLTs on collagen. On the other hand, the total amount of PRT-treated PLTs deposited was higher than that of control PLTs. The promotive effect of PRT treatment on PLT deposition completely disappeared in the presence of tirofiban, a potent integrin αIIbβ3 inhibitor. The percentage of the dissociation of PRT-treated PLTs on collagen was lower than that of control PLTs after flushing with phosphate-buffered saline. PRT treatment significantly inhibited PLT aggregation under high-shear-stress conditions. CONCLUSION Riboflavin-based PRT treatment of PCs leads to the enhancement of PLT thrombus formation and thrombus stability on collagen. However, it does not enhance the reactivity of PLTs not in contact with collagen under high-shear-stress conditions.

Made available in DSpace on 2020-12-12T01:39:42Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-01-01 Antibacterial dental implants and related prosthetic components could help to reduce infection and prevent peri-implantitis. The purpose of this study was to determine the effect of ultraviolet (UV) light treatment of titanium on biofilm formation of human oral bacteria. Materials and Methods: Machineprepared commercially pure titanium disks were treated with UV light for 12 minutes. Human oral bacteria were seeded onto untreated and UV-treated disks. Early bacterial attachment to titanium was assessed at 12 hours. Surface topography of initial biofilms was evaluated by 3D scanning electron microscopy at 24 hours. The quantity and morphology of subsequent colony development and biofilm formation were examined by confocal laser scanning microscopy for up to 7 days. Results: Throughout the time course, significantly fewer bacterial cells attached to UV-treated titanium surfaces compared with untreated ones. While biofilm developed rapidly to a final thickness of approximately 16 μm by day 3 on untreated titanium, on UV-treated surfaces it remained below 8 μm, even at day 7. Similarly, UV treatment resulted in 70% less exopolysaccharide (EPS) volume than on untreated surfaces at day 7. This is consistent with the finding that EPS production per cell was significantly lower on UV-treated surfaces. Untreated titanium surfaces covered with biofilm were fivefold rougher than the original machined surface, while UV-treated surfaces remained twofold rougher due to significantly less biofilm formation. Conclusion: UV treatment of titanium surfaces significantly reduces attachment of human oral bacteria and subsequent biofilm formation as well as EPS production for at least 7 days. UV treatment prevented the escalation of surface colonization, mitigating an unfavorable bacteriophilic cascade and environmental trigger for biofilm formation. Weintraub Center for Reconstructive Biotechnology Division of Advanced Prosthodontics UCLA School of Dentistry Division of Oral Biology and Medicine UCLA School of Dentistry Department of Dental Materials and Prosthodontics School of Dentistry at Araraquara São Paulo State University - UNESP The Forsyth Institute Division of Constitutive and Regenerative Sciences UCLA School of Dentistry Department of Dental Materials and Prosthodontics School of Dentistry at Araraquara São Paulo State University - UNESP

Decontamination of egg shells is required to improve the microbiological safety of the fresh hen eggs used for human consumption or for hatching. Conventional chemical decontamination methods invol...

The objective of this study was to evaluate the effect of ultraviolet light treatment, known as photofunctionalization, on the biological and osseointegration capability of nanofeatured titanium created by a combination of sandblasting and hydrofluoric acid treatment. Titanium samples in disk and cylinder forms were photofunctionalized by treatment with ultraviolet light for 15 min. The nanofeatured surface was converted from hydrophobic to superhydrophilic after photofunctionalization. The strength of osseointegration measured by a biomechanical push-in test in a rat model was stronger for photofunctionalized implants than for untreated implants by 2.2 and 2.3 times, respectively, at the early (week 2) and late (week 4) stages of healing, implying that photofunctionalization did not only accelerate but also increased the degree of osseointegration. Culture studies using bone marrow-derived osteoblasts showed that the attachment, spread, and functional phenotypes of osteogenic cells, such as alkaline phosphatase activity and mineralization, were remarkably increased on photofunctionalized titanium. In conclusion, photofunctionalization substantially increased biological and osseointegration capability of a nanofeatured titanium surface. In light with proven effectiveness on microfeatured surfaces in the literature, photofunctionalization may provide a novel and practical avenue to further improve osseointegration capability of implants in a wide range of surface morphology with micro-to-nano features.

Format: pdf Download now Municipal wastewater treatment plant discharges are a recognised source of human pathogenic viruses. Of concern within this group is norovirus the leading cause of viral gastroenteritis worldwide. This project investigated the use of FRNA bacteriophage as (i) a potential surrogate for norovirus response/behaviour and (ii) a model to determine the fate of viruses through a municipal wastewater treatment plant. The project also evaluated the efficacy of membrane filtration (microfiltration and ultrafiltration) as pathogen removal method and two ultraviolet-based technologies; pulsed UV and low pressure UV as pathogen disinfection methods. The potential impacts of parameters suchas organic carbon, metals and suspended solids, (typically present in wastewater) on the investigated pathogen removal processes were also analysed. non-peer-reviewed

Introducing invasive species in new environments through ballast water is a specific problem of contamination and has recently become one of the main concerns of Maritime Organizations. Ultraviolet-C radiation (UV-C) is a technological alternative to prevent this maritime pollution. This study addresses the effect of UV-C on different phytoplankton cultures and also the ability to recover following exposure to damage. A UV-C low-pressure lamp irradiates the cultures. The distance from the source and the thickness of the layer prevent part of the energy from reaching the culture and the disinfective process is diminished. Some cultures such as Chlorella autotrophica and Chaetoceros calcitrans can easily recover from UV-C damage. However, Phaeocystis globosa does not have this ability. C. calcitrans forms cysts and exhibits two different behaviours depending on the dose applied.

Purpose To assess the safety to the corneal endothelium of ultraviolet (UV) light treatment to a light-adjustable intraocular lens (IOL). Setting Codet Vision Institute, Tijuana, Mexico. Design Cohort study. Methods The study evaluated consecutive patients scheduled for phacoemulsification cataract surgery with implantation of a light-adjustable IOL. Endothelial cell density (ECD), variation in the size of endothelial cells, and the percentage of hexagonal cells were determined centrally with a specular microscope preoperatively, 1 week postoperatively (before UV treatment), and 6 months postoperatively. Two adjustments and 2 lock-in procedures were performed with a light-delivery system between 2 weeks and 4 weeks postoperatively. Results The study enrolled 10 patients. Specular microscopy showed a mean ECD of 2344 cells/mm2 preoperatively. The mean overall central ECD was 2047 cells/mm2 1 week postoperatively and 2130 cells/mm2 at 6 months, representing an endothelial cell loss of 12.6% and 9.1%, respectively, from preoperative values. There was no statistically significant difference in the coefficient of variation or percentage of hexagonal cells at either postoperative evaluation. Conclusions The endothelial cell loss at 6 months correlated well with previous reports of endothelial damage after phacoemulsification with IOL implantation. The light-adjustable IOL irradiation protocol for adjustment and lock-in procedures did not seem to add to the endothelial damage caused by the cataract surgery, indicating the protocol is safe to the corneal endothelium. Financial Disclosure Drs. Lichtinger and Padilla have no financial or proprietary interest in any material or method mentioned. Additional disclosures are found in the footnotes.

Control of disease in shellfish culture is a complex and pervasive problem which can cause extensive loss of time, money, and efficiency. Many shellfish diseases are caused by pathogenic bacteria introduced into the hatchery system through a contaminated water source, an infected animal from natural waters, or a tainted food supply. It is the intent of this paper to explore 4 methods of bacterial disinfection in shellfish hatcheries: ultraviolet light treatment of bacterial shellfish pathogens, the addition of silver (AgNO3) to shellfish larval culture waters, ozone disinfection of contaminated culture water, and standard antibiotic treatment (neomycin) in shellfish hatchery disease control. The efficacy of each system is examined and recommendations are made for the incorporation of standard disease prevention methods in shellfish hatchery operations.

The challenge of providing fruits and vegetables free from contamination with human pathogens has led to the development and optimization of a variety of postharvest-processing technologies. This chapter summarizes recent research related to chemical and physical treatments for fresh and fresh-cut produce. The technologies discussed range from optimizations and advances in conventional treatments, such as antimicrobial sanitizers and modified atmosphere packaging, to applications of established nonthermal processes, such as irradiation and ultraviolet light treatment. Novel tools such as cold plasma also are reviewed. Finally, the criteria for successful commercial adoption of new fresh produce processing tools are summarized.

Background Protection of bioreactors from viruses and mycoplasma remains a challenge. While the risk of these contaminations is known, and several recent high profile cases have raised awareness of this risk, many bioreactors remain unprotected. Currently available technologies, such as high-temperature short-time treatment and ultraviolet light treatment, can be difficult to implement due to footprint, efficacy, and media compatibility issues. Size exclusion nanofiltration may be a more ideal technology for virus and mycoplasma protection, potentially offering advantages in robustness, scalability, small footprint, and media compatibility. However, current virus removal filters, designed for monoclonal antibody purification, are generally poorly suited for cell culture media processes due to the large membrane surface areas needed to achieve adequate flow and capacity in a reasonable timeframe. Here we evaluate a novel virus barrier filter specifically developed for cell culture media applications.

A comparison of ultraviolet (UV) irradiation of two wavelength ranges UVB (280-320 nm) and UVC (lower than 280 nm) showed that UVC in particular could very effectively inactivate, in intravenous immunoglobulin (IVIG) and albumin preparations, non-enveloped and non-acid labile model viruses (i.e., Polio 2 and T4 phage) and dry heat-resistant viruses (vaccinia and T4 phage). This effective virucidal treatment (5 min, 5,000 J/m2 dose) was achieved before an unacceptable level of IVIG aggregates occurred. The use of UV irradiation to inactivate infectious agents could add safety and supplement current methods, e.g. solvent/detergent, low pH, which do not inactivate non-enveloped, non-acid labile or dry-heat-resistant viruses at present.

The authors have developed a treatment process to improve the etch resistance of an electron beam lithography resist (ZEP 520A) to allow direct pattern transfer from the resist into a hard mask using plasma etching without a metal lift-off process. When heated to 90 °C and exposed for 17 min to a dose of approximately 8 mW/cm2 at 248 nm, changes occur in the resist that are observable using infrared spectroscopy. These changes increase the etch resistance of ZEP 520A to a CF4/O2 plasma. This article will document the observed changes in the improved etch resistance of the ZEP 520A electron beam resist.

SUMMARY Contact sensitivity to nitrogen mustard was delayed after first treating patients with u.v. light. While the number of patients becoming sensitive to nitrogen mustard after ultraviolet light exposure was not significantly different from the control, the number of patients who became sensitive in the first 30 days was significantly less than the control group. It is postulated that this delay in sensitization is due to an alteration of the patients’ epidermal Langerhans cells, produced by the u.v. light exposure.

The obstinacy with which chronic otitis media resists treatments is discouraging to the general practitioner, as well as to the specialist. Many therapeutic measures have been suggested for this disease, but the large number of them is proof enough of their inadequacy. On the other hand, the patient, not realizing the obdurate chronicity of the condition, usually blames the physician for incompetency to cure his ear, and starts to make a round of various specialists, without giving any of them time to study the case thoroughly. This difficulty in systematically following up cases of chronic otitis media over a long period must be taken into consideration before one passes judgment as to which of the therapeutic applications is more efficacious. In tuberculosis institutions, cases of chronic otitis media can be followed more or less systematically, as the patients remain for a long period, because of the pulmonary condition. In

Because it is difficult to visualize the three-dimensional shape of uterine cavities only through observation of transverse tissue specimens, careful casting was done for mouse uterine cavities and the casts were observed under a stereoscopic microscope.Eighty-nine ICR strain female mice were divided into three groups: cyclic mice (proestrus, estrus, metestrus I, metestrus II, diestrus), ovariectomized mice (5, 10, 15 days after ovariectomy) and mice administered daily with progesterone after ovariectomy (5, 10, 15 days after ovariectomy). When their uteri were taken, casting of the uterine cavities was done by the method of MURAKAMI et al. (1984) which does not require partial polymerization by heating nor ultraviolet light treatment prior to injection.The casts were different in length, width and configuration among those under physiological con-ditions. The casts were like thick ribbons or rather worn-out tapes with widths and thicknesses different at places and some were wrinkling irregularly all along the lengths. The casts were found in the uteri with one edge always toward the mesometrium throughout its length. These casts observed in this study help us imagine how uterine cavities lie in mouse uteri.

The purpose of this case report is to detail the physical therapy of a patient with pityriasis lichenoides et varioliformis acuta (Mucha-Habermann disease), a condition usually not encountered by physical therapists. Prolonged exposure to ultraviolet light was the effective mode of treatment.

To the Editor.— Eighteen light-tolerant patients with widespread psoriasis were treated with 15 minutes of a 37 C warm bath with 50 mg of trioxsalen in 100 liters of water. The trioxsalen added was dissolved in 100 ml of 70% alcohol. Immediately after the bath, the skin was irradiated with a set of lamps for ten to 300 seconds at a distance of 60 cm. 1 The lamp gives 0.8M W/sq cm of ultraviolet (UV)-B and 13M W/sq cm of UV-A. The treatment was given five days per week. One arm was left for treatment with coal tar bath, UV light, and stiff dithranol paste. 2 After two to five weeks, the psoriasis had almost or completely healed on the trioxsalentreated skin. The arm treated with the Ingram regimen 2 healed slower in nine patients, faster in one, and at the same rate in the others. It is possible that

My experiences in treating a large number of cases of psoriasis locally with the mercury quartz lamp during the last few years have convinced me that this therapy constitutes a relatively satisfactory and cleanly method. While it is not invariably successful, I have often observed that psoriasis lesions clear up more effectively than under any other form of treatment except roentgenotherapy. For various reasons, I prefer the former; I believe that recurrences are delayed longer after successful ultraviolet light treatment. It seems to me to be safer and more desirable when the scalp is involved, although I realize that it is stated on very good authority that roentgenotherapy is safe and effective. I now have a patient with psoriasis in my care suffering from alopecia due to roentgen-ray treatments administered by a local expert for the eradication of psoriasis lesions of the scalp. The lesions have been eradicated, and so