Hydrogen Peroxide Production of Individual Nanosecond Pulsed Discharges Submerged in Water of Elevated Conductivity

The production of hydrogen peroxide (H2 O2 ) is a key parameter for the performance of pulsed discharges submerged in water utilized as advanced oxidation process. So far, any related assessment of the underlying mechanism was conducted for the application of several hundred discharges, which did not allow for a correlation with physical processes. Moreover, the production was rarely investigated depending on water conductivity as one of the most important parameters for the development of submerged discharges. Accordingly, hydrogen peroxide generation was investigated here for individual single discharge events instigated with 100 ns high-voltage pulses in water with three different conductivities and was associated with the discharge development, i. e. spatial expansion and dissipated electrical energy. The approach necessitated the improvement of an electrochemical flow injection analysis based on the reaction of Prussian blue with H2 O2 . Hydrogen peroxide concentrations were quadratically increasing with propagation time and stable for different water conductivities. H2 O2 production per unit volume of a discharge was constant over time with an estimated rate constant of 3.2 mol ⋅ m-1  s-1 , averaged over the crosssectional area of all discharge filaments. However, the individually dissipated energy increased with conductivity, hence, the production efficiency decreased from 6.1 g ⋅ kWh-1 to 1.4 g ⋅ kWh-1 , which was explained by increased resistive losses within the bulk liquid.

Plasma-Treated Water: A Comparison with Analog Mixtures of Traceable Ingredients

Plasma-treated water (PTW) possess anti-microbial potential against Pseudomonas fluorescence, which is observable for both suspended cells and cells organized in biofilms. Against that background, the chemical composition of PTW tends to focus. Various analytical techniques have been applied for analyses, which reveal various traceable reactive oxygen and nitrogen compounds (RONS). Based on these findings, it is our aim to generate a PTW analog (anPTW), which has been compared in its anti-microbial efficiency with freshly generated PTW. Additionally, a solution of every traceable compound of PTW has been mixed according to their PTW concentration. As references, we treated suspended cells and mature biofilms of P. fluorescence with PTW that originates from a microwave-driven plasma source. The anti-microbial efficiency of all solutions has been tested based on a combination of a proliferation, an XTT, and a live–dead assay. The outcomes of the test proved an anti-microbial power of PTW that suggests more active ingredients than the traceable compounds HNO3, HNO2, and H2O2 or the combined mixture of the analog.

Impact of different oral treatments on the composition of the supragingival plaque microbiome

Background

Dental plaque consists of a diverse microbial community embedded in a complex structure of exopolysaccharides. Dental biofilms form a natural barrier against pathogens but lead to oral diseases in a dysbiotic state.

Objective

Using a metaproteome approach combined with a standard plaque-regrowth study, this pilot study examined the impact of different concentrations of lactoperoxidase (LPO) on early plaque formation, and active biological processes.

Design

Sixteen orally healthy subjects received four local treatments as a randomized single-blind study based on a cross-over design. Two lozenges containing components of the LPO-system in different concentrations were compared to a placebo and Listerine®. The newly formed dental plaque was analyzed by mass spectrometry (nLC-MS/MS). 

Results

On average 1,916 metaproteins per sample were identified, which could be assigned to 116 genera and 1,316 protein functions. Listerine® reduced the number of metaproteins and their relative abundance, confirming the plaque inhibiting effect. The LPO-lozenges triggered mainly higher metaprotein abundances of early and secondary colonizers as well as bacteria associated with dental health but also periodontitis. Functional information indicated plaque biofilm growth.

Conclusion

In conclusion, the mechanisms on plaque biofilm formation of Listerine® and the LPO-system containing lozenges are different. In contrast to Listerine®, the lozenges led to a higher bacterial diversity.

Antibacterial and antiplaque efficacy of a lactoperoxidase-thiocyanate-hydrogen-peroxide-system-containing lozenge

Background

Antimicrobial agents are considered valuable adjuncts to mechanical methods of plaque control. However, their long-term use can be limited because of side effects.

Therefore, using physiological substances is promising due to no risk of development, for example, of microbial resistances, allergies or DNA damaging. The lactoperoxidase-thiocyanate-hydrogen peroxide system (LPO-system) is a highly effective antimicrobial system. This study aimed to evaluate in a randomized study with a four-replicate cross-over design the effectiveness of two oral hygiene lozenges containing LPO-system in oral hygiene.

Results

After using the mouth rinse as positive control (A) and allocated test lozenges (B) (0.083% H₂O₂) & (C) (0.04% H₂O₂) for 4 days instead of the normal oral hygiene procedures (tooth brushing etc.), Listerine rinse (A) was statistically significantly more effective than the LPO-system-lozenge with 0.083% H₂O₂, the LPO-system-lozenge with 0.04% H₂O₂, and the placebo lozenge (D) in inhibiting plaque. Lozenges B and C were statistically significantly more effective than the placebo lozenge, but no statistically significant differences could be observed between them.

The LPO-system-lozenge (B) reduced statistically significantly more S. mutans than the LPO-system-lozenge with (C) and the placebo lozenge (D). The LPO-system-lozenge (C) reduced statistically significantly more Lactobacilli than Listerine (A), the LPO-system-lozenge (B) and the placebo lozenge (D). There were no statistically significant differences in the total CFUs between Listerine rinse, the LPO-system-lozenge with 0.083% H₂O₂ (B), the LPO-system-lozenge with 0.04% H₂O₂ (C), and the placebo lozenge (D). On day 5 there were no differences of the OSCN⁻-values between all A, B, C, and D. However, the SCN⁻-values increased over the days in both LPO-system-lozenges (B/C). The statistically significant differences between B/C and A/D on day 5 were as followed: A to B p = 0.0268; A to C p = 0.0035; B to D p = 0.0051; C to D p = 0.0007. Only in the group of Listerine (A) increased the NO₃⁻/NO₂⁻-quotient over the test time, which indicates a reduction of nitrate-reducing bacteria. On Day 5 the statistically significant difference between A and B was p = 0.0123.

Conclusions

The results indicate that lozenges containing a complete LPO-system, inhibiting plaque regrowth and reducing cariogenic bacteria, may be used in the daily oral hygiene.

Variability of Thyroid Measurements from Ultrasound and Laboratory in a Repeated Measurements Study

BACKGROUND

Variability of measurements in medical research can be due to different sources. Quantification of measurement errors facilitates probabilistic sensitivity analyses in future research to minimize potential bias in epidemiological studies. We aimed to investigate the variation of thyroid-related outcomes derived from ultrasound (US) and laboratory analyses in a repeated measurements study.

SUBJECTS AND METHODS

Twenty-five volunteers (13 females, 12 males) aged 22-70 years were examined once a month over 1 year. US measurements included thyroid volume, goiter, and thyroid nodules. Laboratory measurements included urinary iodine concentrations and serum levels of thyroid-stimulating hormone (TSH), free triiodothyronine (fT3), free thyroxine (fT4), and thyroglobulin. Variations in continuous thyroid markers were assessed as coefficient of variation (CV) defined as mean of the individual CVs with bootstrapped confidence intervals and as intraclass correlation coefficients (ICCs). Variations in dichotomous thyroid markers were assessed by Cohen's kappa.

RESULTS

CV was highest for urinary iodine concentrations (56.9%), followed by TSH (27.2%), thyroglobulin (18.2%), thyroid volume (10.5%), fT3 (8.1%), and fT4 (6.3%). The ICC was lowest for urinary iodine concentrations (0.42), followed by fT3 (0.55), TSH (0.64), fT4 (0.72), thyroid volume (0.87), and thyroglobulin (0.90). Cohen's kappa values for the presence of goiter or thyroid nodules were 0.64 and 0.70, respectively.

CONCLUSION

Our study provides measures of variation for thyroid outcomes, which can be used for probabilistic sensitivity analyses of epidemiological data. The low intraindividual variation of serum thyroglobulin in comparison to urinary iodine concentrations emphasizes the potential of thyroglobulin as marker for the iodine status of populations.

The Effect of Plasma Treated Water Unit Processes on the Food Quality Characteristics of Fresh-Cut Endive

This study evaluated the impact of a defined plasma treated water (PTW) when applied to various stages within fresh-cut endive processing. The quality characteristic responses were investigated to establish the impact of the PTW unit processes and where PTW may be optimally applied in a model process line to retain or improve produce quality. Different stages of application of PTW within the washing process were investigated and compared to tap water and chlorine dioxide. Fresh-cut endive (Cichorium endivia L.) samples were analyzed for retention of food quality characteristics. Measurements included color, texture, and nitrate quantification. Effects on tissue surface and cell organelles were observed through scanning electron and atomic force microscopy. Overall, the endive quality characteristics were retained by incorporating PTW in the washing process. Furthermore, promising results for color and texture characteristics were observed, which were supported by the microscopic assays of the vegetal tissue. While ion chromatography detected high concentrations of nitrite and nitrate in PTW, these did not affect the nitrate concentration of the lettuce tissue post-processing and were below the concentrations within EU regulations. These results provide a pathway to scale up the industrial application of PTW to improve and retain quality characteristic retention of fresh leafy products, whilst also harnessing the plasma functionalized water as a process intervention for reducing microbial load at multiple points, whether on the food surface, within the process water or on food-processing surfaces.

Influence of Bio-sorb® Cream on Sweat Production and Efficacy of Surgical Hand Antisepsis Under Surgical Gloves

Aim: Since the introduction of surgical gloves, one of the main challenges has been to improve donning and wearability. For the wearer, the formation of "glove juice" is problematic. To improve gliding properties for donning the gloves and absorbing sweat, in 1963 Bio-sorb^® cream: sterile powder cream (Johnson & Johnson Medical, Gargrave, Skipton, United Kingdom) was introduced. Individuals subjectively reported a reduction of sweat production inside the glove, however, the actual effect on sweat accumulation and surgical hand antisepsis has not been examined. Methods: Twenty-six volunteers were used in a study designed to examine the effect of a sterile hand cream applied after surgical hand antisepsis on sweat accumulation inside surgical gloves. A woven cotton glove was worn underneath the surgical glove. Weight differences were used to determine the amount of sweat produced. The influence of Bio-sorb on the efficacy of surgical hand antisepsis was tested immediately and after 90 minutes of wear time by the sampling technique as per EN 12791 and by bacterial analysis of glove juice according to tentative final monograph 1994. Results and Discussion: The amount of sweat produced inside the glove was not reduced by the cream (1.07 ± 0.5 g versus control 1.03 ± 0.5 g; p = 0.75). Considering different skin conditions, it may be possible that some wearers might subjectively observe decreased sweat production after using Bio-sorb cream before donning surgical gloves, because sweat production did decrease in 10 of 26 test subjects. Bio-sorb cream did not affect the efficacy of surgical hand antisepsis either immediately or after 90 minutes. Conclusion: Because of possible risks of contamination of the surgical site with cornstarch from Bio-sorb cream in the case of a glove breach and the failed statistical proof of reduced sweat production, the use of Bio-sorb cream should not to be recommended.

Do pneumatic tube transport systems transmit potential pathogens? A hygienic risk assessment in a university hospital

BACKGROUND

Prompted by an outbreak of vancomycin-resistant enterococci (VRE) in a medical facility, this study examined a pneumatic tube transport system (PTS) as a potential transmission channel.

METHOD

Samples from the receiving station and entry racks were gathered via smear technique. Sponges used for PTS decontamination were soaked with 0.89% NaCl and transported through the channel. Micro-organisms were recovered from the tubes and cleaning sponges using a wash-away technique. Air sampling was performed at the receiving station in order to detect any airborne contamination. Tubes were artificially inoculated with Escherichia coli K12 NCTC 10538 and Staphylococcus epidermidis DSM 20044 and sent through the PTS to investigate channel contamination.

RESULTS

No pathogens were detected in effluent air from the PTS or in tubes during routine operation. Entry racks for the test tubes were contaminated with coagulase-negative staphylococci (CNS), aerobic bacilli, moulds and vancomycin-susceptible Enterococcus faecium. E. coli proved to be unsuitable for detecting bacterial transmission by the PTS due to low persistence, but S. epidermidis was more resilient. After sending contaminated test tubes through the PTS, levels of S. epidermidis only decreased marginally. Subsequently, sponges soaked with disinfectant solution were put through the system and these eliminated S. epidermidis completely from the first attempt.

DISCUSSION

Routine hygienic maintenance of the PTS makes pathogen transmission highly unlikely, although entry racks should be disinfected regularly. Any involvement of the PTS in the VRE outbreak at the study institution was unlikely.

Plasma-Treated Air and Water-Assessment of Synergistic Antimicrobial Effects for Sanitation of Food Processing Surfaces and Environment

The synergistic antimicrobial effects of plasma-processed air (PPA) and plasma-treated water (PTW), which are indirectly generated by a microwave-induced non-atmospheric pressure plasma, were investigated with the aid of proliferation assays. For this purpose, microorganisms (Listeria monocytogenes, Escherichia coli, Pectobacterium carotovorum, sporulated Bacillus atrophaeus) were cultivated as monocultures on specimens with polymeric surface structures. Both the distinct and synergistic antimicrobial potential of PPA and PTW were governed by the plasma-on time (5⁻50 s) and the treatment time of the specimens with PPA/PTW (1⁻5 min). In single PTW treatment of the bacteria, an elevation of the reduction factor with increasing treatment time could be observed (e.g., reduction factor of 2.4 to 3.0 for P. carotovorum). In comparison, the combination of PTW and subsequent PPA treatment leads to synergistic effects that are clearly not induced by longer treatment times. These findings have been valid for all bacteria (L. monocytogenes > P. carotovorum = E. coli). Controversially, the effect is reversed for endospores of B. atrophaeus. With pure PPA treatment, a strong inactivation at 50 s plasma-on time is detectable, whereas single PTW treatment shows no effect even with increasing treatment parameters. The use of synergistic effects of PTW for cleaning and PPA for drying shows a clear alternative for currently used sanitation methods in production plants. Highlights: Non-thermal atmospheric pressure microwave plasma source used indirect in two different modes-gaseous and liquid; Measurement of short and long-living nitrite and nitrate in corrosive gas PPA (plasma-processed air) and complex liquid PTW (plasma-treated water); Application of PTW and PPA in single and combined use for biological decontamination of different microorganisms.

Evaluation of three experimental in vitro models for the assessment of the mechanical cleansing efficacy of wound irrigation solutions

The aim of this study was to compare different wound-rinsing solutions to determine differences in the efficiency and to evaluate three different in vitro models for wound cleansing. Different wound-rinsing solutions (physiological saline solution, ringer lactate solution for wound irrigation, water and a solution containing polihexanide and the surfactant undecylenamidopropyl-betain) were applied on standardised test models (one- and three-chamber model, flow-cell method and a biofilm model), each challenged with three different standardised wound test soils. In the one-chamber model saline showed a better effect on decontaminating proteins than the ringer lactate solution. In the flow-cell method, water performed better than physiological saline solution, whereas ringer lactate solution demonstrated the lowest cleansing effect. No obvious superiority between the two electrolyte-containing solutions was detectable in the biofilm model. Unfortunately, it was not possible to assess the protein decontamination qualities of the surfactant-containing solution because of the interference with the protein measurement. The flow-cell method was able to detect differences between different rinse solutions because it works at constant flow mechanics, imitating a wound-rinsing procedure. The three-chamber and the less-pronounced modified one-chamber method as well as the biofilm model had generated inhomogeneous results.

Interlaboratory variability of urinary iodine measurements

Background:

The iodine status of populations is usually assessed by median urinary iodine concentrations (UIC) in population-based studies, but it is unclear to which extent UIC are comparable across different laboratories. The aim of our study was to investigate the variability of UIC measurements across three well-established German laboratories with long-term clinical-chemical expertise in iodine measurements and to compare these results to the gold standard inductively coupled plasma mass spectrometry (ICP-MS).

Methods:

UIC levels were measured from 303 urine samples derived from the “Dortmund Nutritional and Anthropometric Longitudinally Designed Study” and from volunteers of the University Medicine Greifswald at four different German laboratories. Three of these laboratories used Sandell-Kolthoff reaction with different digestion methods for UIC measurement (Lab1–Lab3), whereas one laboratory used ICP-MS as gold standard.

Results:

Median UIC levels were significantly different across the four laboratories (ICP-MS: 77 μg/L; Lab1: 69 μg/L; Lab2: 73 μg/L; Lab3: 111 μg/L). Linear regressions associating UIC levels of Lab1–Lab3 with UIC levels of ICP-MS showed intercepts significantly different from 0 and slopes significantly different from 1. Intraclass correlations (ICC) in comparison to ICP-MS were 0.91 for Lab1, 0.98 for Lab2, and 0.69 for Lab3. Using the digestion method of Lab2 in Lab3 improved the comparison of UIC levels of Lab3 with those from the ICP-MS (ICC=0.89).

Conclusions:

We have demonstrated larger interlaboratory variations across high-quality laboratories with long-lasting experience in iodine measurements indicating a relevant non-comparability of UIC measurements in iodine monitoring studies. Therefore, standardization of UIC measurements has to be expedited.

Association of salivary peroxidase activity and concentration with periodontal health: A validity study

AIM

Whereas the relationship between myeloperoxidase and periodontitis has been widely examined that between salivary peroxidase and periodontitis has received little attention. We examined how periodontitis depends on both salivary peroxidase activity and concentration.

MATERIALS AND METHODS

A full mouth, clinical assessment of probing depth was performed in a sample of 46 participants aged 25-54 years. To minimise bias, these data were corrected by data from the general population (Study of Health in Pomerania). Using five repeated measurements of activity and concentration over 1 day, we assessed daily biological variability and increased the reliability of salivary peroxidase measurements.

RESULTS

Salivary peroxidase activity was associated with probing depth (interquartile range effect = -0.48; robust estimates of 95% confidence interval: -0.90 to -0.31; p = .0052), and its effect was not confounded by salivary peroxidase concentration. In turn, the effect of salivary peroxidase concentration was confounded by salivary peroxidase activity, and it was smaller than that of activity.

CONCLUSIONS

We found an inverse association between salivary peroxidase activity and probing depth. Thus, our results imply that salivary peroxidase activity could be a protective factor against periodontitis. However, large, well-designed studies are needed to explore the causal mechanisms of this association.

Monitoring the prevalence of thyroid disorders in the adult population of Northeast Germany

BACKGROUND

Only a few studies like ours have investigated the effect of long-term stable iodine supply on thyroid disorders in a historically iodine-deficient population, but not with a long follow-up time of 10 years.

METHODS

Data were derived from two independent population-based cohorts of the Study of Health in Pomerania (SHIP-0 [1997-2001] and SHIP-TREND [2008-2012]) comprising 4308 and 4420 subjects, respectively. Diagnosed thyroid disorders were assessed. Thyroid gland dimensions were examined by ultrasound. Levels of serum thyrotropin (TSH) and autoantibodies to thyroperoxidase (anti-TPO Abs) were measured from blood samples.

RESULTS

Median urinary iodine excretion levels decreased from 123.0 μg/l to 112.0 μg/l (p = <0.001) between 2000 and 2010. The prevalence of known thyroid disorders increased from 7.6 % [CI 6.9-8.5] to 18.9 % [CI 17.6-20.1] and of thyroid medication use from 6.2 to 11.1 %. The prevalence of goiter decreased from 35.1 to 29.4 % (p = <0.001), while the prevalence of positive anti-TPO Abs decreased from 3.9 to 2.9 % (p = 0.022). Median serum TSH levels increased from 0.69 mIU/L to 1.19 mIU/L (p = <0.001). Consequently, prevalence of high TSH (mIU/L) increased from 2.6 to 2.9 % (p = 0.452), and low TSH (mIU/L) decreased from 6.6 to 6.4 % (p = 0.737).

CONCLUSION

The decreased prevalence of iodine-deficient disorders and a stable prevalence of markers of autoimmune thyroid disorders argue for an improved iodine supply of the adult population in Northeast Germany. In contrast, the prevalence of diagnosed thyroid disorders and the intake of thyroid medication increased, although this might be related to inappropriate therapeutic decisions.

Measurements of chlorhexidine, p-chloroaniline, and p-chloronitrobenzene in saliva after mouth wash before and after operation with 0.2% chlorhexidine digluconate in maxillofacial surgery: a randomised controlled trial

Chlorhexidine gluconate is used to prevent the accumulation of dental plaque and gingivitis, infection of the surgical site, and ventilator-associated pneumonia in maxillofacial surgery, but it is not clear whether the metabolites of chlorhexidine are detectable in the patient's saliva at clinically relevant concentrations. Forty-three patients who had orofacial operations were randomised to use a 0.2% chlorhexidine gluconate (n=23), or an octenidine-based, chlorhexidine-free (n=20), mouthwash once preoperatively and three times daily for five postoperative days. After the first, 8.7 (23.3) mg/L chlorhexidine (0.7%-2.5% of the total amount used) was measured in saliva. The concentration increased to 15.2 (6.2) mg/L after the second rinse (first postoperative day), and peaked at 29.4 (11.2) mg/L on the fourth postoperative day. It remained detectable for up to 12hours after the last one, but was not detectable in serum or urine at any time. The potentially carcinogenic metabolite p-chloroaniline was detectable in saliva at higher concentrations in the chlorhexidine group (0.55mg/L) than the octenidine group (0.21mg/L), and p-chloronitrobenzene was detected in both groups in only minimal concentrations (0.001-0.21mg/L). Chlorhexidine gluconate mouthwashes do increase the concentration of p-chloroaniline, but a single use seems to be safe. Whether prolonged exposure over many years may have carcinogenic potential is still not clear. Based on the hitherto unknown kinetics of p-chloroaniline in saliva, the recent recommendation of the Federal Drug Administration (FDA) in the USA to limit the use of a chlorhexidine gluconate mouthwash to a maximum of six months seems to be justified.

Ethanol and ethyl glucuronide urine concentrations after ethanol-based hand antisepsis with and without permitted alcohol consumption

BACKGROUND

During hand antisepsis, health care workers (HCWs) are exposed to alcohol by dermal contact and by inhalation. Concerns have been raised that high alcohol absorptions may adversely affect HCWs, particularly certain vulnerable individuals such as pregnant women or individuals with genetic deficiencies of aldehyde dehydrogenase.

METHODS

We investigated the kinetics of HCWs' urinary concentrations of ethanol and its metabolite ethyl glucuronide (EtG) during clinical work with and without previous consumption of alcoholic beverages by HCWs.

RESULTS

The median ethanol concentration was 0.7 mg/L (interquartile range [IQR], 0.5-1.9 mg/L; maximum, 9.2 mg/L) during abstinence and 12.2 mg/L (IQR, 1.5-139.6 mg/L; maximum, 1,020.1 mg/L) during alcohol consumption. During abstinence, EtG reached concentrations of up to 958 ng/mL. When alcohol consumption was permitted, the median EtG concentration of all samples was 2,593 ng/mL (IQR, 890.8-3,576 ng/mL; maximum, 5,043 ng/mL). Although alcohol consumption was strongly correlated with both EtG and ethanol in urine, no significant correlation for the frequency of alcoholic hand antisepsis was observed in the linear mixed models.

CONCLUSIONS

The use of ethanol-based handrub induces measurable ethanol and EtG concentrations in urine. Compared with consumption of alcoholic beverages or use of consumer products containing ethanol, the amount of ethanol absorption resulting from handrub applications is negligible. In practice, there is no evidence of any harmful effect of using ethanol-based handrubs as much as it is clinically necessary.

Investigating the Mutagenicity of a Cold Argon-Plasma Jet in an HET-MN Model

OBJECTIVE

So-called cold physical plasmas for biomedical applications generate reactive oxygen and nitrogen species and the latter can trigger DNA damage at high concentrations. Therefore, the mutagenic risks of a certified atmospheric pressure argon plasma jet (kINPen MED) and its predecessor model (kINPen 09) were assessed.

METHODS

Inner egg membranes of fertilized chicken eggs received a single treatment with either the kINPen 09 (1.5, 2.0, or 2.5 min) or the kINPen MED (3, 4, 5, or 10 min). After three days of incubation, blood smears (panoptic May-Grünwald-Giemsa stain) were performed, and 1000 erythrocytes per egg were evaluated for the presence of polychromatic and normochromic nuclear staining as well as nuclear aberrations and binucleated cells (hen's egg test for micronuclei induction, HET-MN). At the same time, the embryo mortality was documented. For each experiment, positive controls (cyclophosphamide and methotrexate) and negative controls (NaCl-solution, argon gas) were included. Additionally, the antioxidant potential of the blood plasma was assessed by ascorbic acid oxidation assay after treatment.

RESULTS

For both plasma sources, there was no evidence of genotoxicity, although at the longest plasma exposure time of 10 min the mortality of the embryos exceeded 40%. The antioxidant potential in the egg's blood plasma was not significantly reduced immediately (p = 0.32) or 1 h (p = 0.19) post exposure to cold plasma.

CONCLUSION

The longest plasma treatment time with the kINPen MED was 5-10 fold above the recommended limit for treatment of chronic wounds in clinics. We did not find mutagenic effects for any plasma treatment time using the either kINPen 09 or kINPen MED. The data provided with the current study seem to confirm the lack of a genotoxic potential suggesting that a veterinary or clinical application of these argon plasma jets does not pose mutagenic risks.

Systemic iodine absorption associated with the use of preoperative ophthalmic antiseptics containing iodine

BACKGROUND

Polyvinylpyrrolidone-Iodine (PVP-I) is routinely used as preoperative antiseptic during ophthalmic surgery. Iodine absorption from iodine-containing antiseptics can lead to the development of thyroid disorders. Therefore, a quantitative measurement of iodine absorption from these antiseptics was performed in patients undergoing elective cataract surgery.

METHODS

This study enrolled 241 patients to evaluate systemic iodine absorption after exposure to conjunctival and/or periorbital 1.25% and 10% PVP-I compared to an iodine-free antiseptic.

RESULTS

All patients who received the 10% PVP-I regardless of the application site showed a 1.2-1.5-fold increase in urinary iodine excretion after 24 h (p = 0.01). In 17 out of 110 (15.5%) patients in whom 10% PVP-I was used, the critical threshold of urinary iodine excretion as defined by WHO (>300 µg/L) was exceeded. In contrast, no significant ioduria was observed with the use of 1.25% PVP-I except in patients after 48 h (p = 0.01) and with a concurrent conjunctival and periorbital application. The proportion of the excreted iodine in urine ranged from 0.24% to 1.77%. No correlation was found between the total applied concentration of iodine and the amount excreted in urine.

CONCLUSION

Based on our findings, we believe that the use of 10% PVP-I as preoperative ophthalmic antiseptic should undergo further clinical evaluation in regard to its impact on thyroid function. Conjunctival or periorbital application of 1.25% PVP-I does not result in significant ioduria.

Association of socioeconomic status with iodine supply and thyroid disorders in northeast Germany

OBJECTIVES

Studies on the potential association of socioeconomic status with iodine supply and the risk for thyroid disorders from developed countries are sparse. Socioeconomic status, however, may particularly impact the efficiency of iodine prophylaxis programs, which are based on the voluntary principle. This study aims to investigate whether the socioeconomic status is cross-sectionally and longitudinally related to low urinary excretion or thyroid disorders in the population of northeast Germany.

METHODS

Data of the population-based Study of Health in Pomerania were used. The study population comprised 4056 adults for cross-sectional and 2860 adults for longitudinal analyses. Assessment of socioeconomic status comprised different scales of education, income, employment, and occupation. Thyroid-related outcomes included urinary iodine excretion, serum thyrotropin, and sonographically defined goiter and nodules. Statistical analyses were adjusted for confounders.

RESULTS

Some of the socioeconomic variables were associated with thyroid-related characteristics in cross-sectional analyses. For example, there was an overall tendency for groups with higher education and higher income to have larger thyroid volumes and an increased risk of goiter. However, most of these associations did not attain statistical significance after correcting the target p-value for multiple testing. Longitudinal analyses did not demonstrate consistent results.

CONCLUSIONS

Socioeconomic status neither substantially influences iodine supply nor does it have a major impact on the prevalence and incidence of thyroid deficiency-related disorders in the adult population of northeast Germany, indicating a good efficacy of the German iodine fortification program in all socioeconomic groups.

Geographic variations in the frequency of thyroid disorders and thyroid peroxidase antibodies in persons without former thyroid disease within Germany

OBJECTIVE

To investigate regional variations in the frequency of undiagnosed thyroid disorders among 25- to 88-year-old men and women in two communities in the northeast and the south of Germany. In addition, autoantibodies to thyroperoxidase (TPO-Abs) and urinary iodine excretion were determined.

METHODS

Two population-based surveys of men and women using a common standardized protocol, the Study of Health in Pomerania (SHIP) in the northeast of Germany (2505 participants) and the Kooperative Gesundheitsforschung in der Region Augsburg (KORA) in the south of Germany (2316 participants), were compared with regard to the frequency of undiagnosed thyroid disorders.

RESULTS

Compared with the northeast of Germany, urinary iodine excretion and serum thyroid-stimulating hormone (TSH) levels were significantly higher in the south. The median urinary iodine concentration was 110 μg/l (64; 169 μg/l) in SHIP and 151 μg/l (97; 214 μg/l) in KORA, and the median TSH value was 0.81 mIU/l (0.56; 1.15 mIU/l) in SHIP and 1.22 mIU/l (0.84; 1.80 mIU/l) in KORA. The frequency of elevated TSH (TSH ≥ 2.12 mIU/l) was 4.3% in SHIP and 14.1% in KORA (P<0.001); the corresponding values for suppressed TSH (<0.25 mIU/l) were 3.5 and 1.7% (P<0.001). The proportion of ultrasonographic findings was 55.5% in SHIP and 68.0% in KORA. The frequency of serum TPO-Abs did not differ significantly between northeast and south Germany.

CONCLUSIONS

There were considerable regional disparities in the frequency of thyroid disorders within Germany. These differences can be explained not only by different regional histories of natural iodine deficiency but also by current differences in the iodine supply under an identical nationwide iodine fortification program.

Five-year change in morphological and functional alterations of the thyroid gland: the Study of Health in Pomerania

BACKGROUND

While cross-sectional data on thyroid epidemiology are common, few longitudinal data on the incidence and progression of thyroid disorders exist. The aim of this study was to analyze the 5-year change and the incidence of morphological and functional alterations of the thyroid gland in a previously iodine-deficient area.

METHODS

We used 5-year follow-up data based on 2941 participants (20-79 years) of the population-based Study of Health in Pomerania. The thyroid structure and size were measured by ultrasonography. Thyroid function and serum autoantibodies to thyroperoxidase (anti-TPO-Ab) were evaluated.

RESULTS

During follow-up, the median iodine/creatinine ratio decreased slightly from 134.2 to 130.4 μg/g. The mean thyroid volume was nonsignificantly increased by 0.73 mL [confidence interval (CI) -1.68-3.41 mL]. The incidence rate of goiter was 34.0 [CI 30.7-37.7] per 1000 person-years (py), the incident rate of nodules was 16.6 [CI 14.5-19.1] per 1000 py. Median serum thyrotropin levels increased slightly (0.10 [CI -0.10-0.34 mIU/L]). The incidence of positive anti-TPO-Ab was 3.4 [CI 2.6-4.7] per 1000 py. For all thyroid parameters, the regression rates were higher than the incidence rates.

CONCLUSIONS

After iodine fortification became effective in this previously iodine-deficient region, there is a negative net balance between occurring and reverting goiter and nodules. Along with balanced incidences of hyper- and hypothyroid dysfunction and the low incidence of autoimmune-related findings, these findings indicate that the current iodine status is sufficient to prevent iodine deficiency-related disorders in the adult population of the study region.

Dermal and pulmonary absorption of propan-1-ol and propan-2-ol from hand rubs

BACKGROUND

It has been shown that nontoxic concentrations of ethanol are absorbed after hand hygiene using ethanol-based hand rubs. This study investigated whether absorption of propan-1-ol and propan-2-ol from commercially available hand rubs results in measurable concentrations after use.

METHODS

The pulmonary and dermal absorption of propanol during hand rubs was investigated. Rubs contained 70% (w/w) propan-1-ol, 63.14% (w/w) propan-2-ol, or 45% (w/w) propan-2-ol in combination with 30% (w/w) propan-1-ol.

RESULTS

Peak median blood levels were 9.15 mg/L for propan-1-ol and 5.3 mg/L for propan-2-ol after hygienic hand rubs and 18.0 mg/L and 10.0 mg/L, respectively, after surgical hand rubs. Under actual surgical conditions, the highest median blood levels were 4.08 mg/L for propan-1-ol and 2.56 mg/L for propan-2-ol. The same procedure performed with prevention of pulmonary exposure through the use of a gas-tight mask resulted in peak median blood levels of 1.16 mg/L of propan-1-ol and 1.74 mg/L of propan-2-ol.

CONCLUSION

Only minimal amounts of propanols are absorbed through the use of hand rubs. Based on our experimental data, the risk of chronic systemic toxic effects caused by hand rubs is likely negligible. However, our study did not evaluate the consequences of long-term daily and frequent use of hygienic hand rubs.

Comparison of the antioxidant potential in urine, saliva and skin

AIM

Free radicals, oxidative stress and their possible consequences for health are becoming increasingly important in modern medicine. Reactive species influence the organism, potentially causing oxidative cell damage. They can be produced by exogenous sources, or be a product of a variety of not only physiological metabolic processes, such as immune response, but also pathological processes. The antioxidant protection system protects the organism from oxidative damage caused by reactions producing an excess of free radicals. The analysis of antioxidant potential (AOP) is therefore becoming increasingly important for the diagnosis of individual vitality.

METHOD

The photochemoluminescence method was used to measure the AOP in urine and saliva, spectrometry was employed to measure the β-carotene content of the skin. In addition, it was investigated whether the AOP(saliva) correlated with the AOPU(urine) (uric-acid independent AOP) as well as the β-carotene content of the skin.

RESULTS

The AOP was significantly higher in urine than in saliva, and both values were significantly positively correlated with each other. However, there was no significant correlation to the β-carotene content of the skin.

DISCUSSION

The components of the AOPU(urine) are accumulated over time (night), whereas AOP measurement in saliva is like a snapshot, which explains why AOPU(urine) was significantly higher than AOP(saliva), although the two parameters are correlated with each other. β-carotene is a fat-soluble antioxidant, whereas in our study, only water-soluble antioxidants were determined in the urine. This explains why there is no positive correlation between β-carotene of the skin and AOP.

CONCLUSION

For the characterization of the AOP in epidemiological studies, we recommend determining the AOPU(urine) and parallel to this, the β-carotene content of the skin.

Decontamination of room air and adjoining wall surfaces by nebulizing hydrogen peroxide

AIM

In 2010, the ASP GLOSAIR(TM) 400 was introduced in Germany for nebulizing hydrogen peroxide (H(2)O(2)). Since there were no results of practical experience, the new method was to be checked under practical conditions for its effectiveness in decontaminating air in rooms, infested with mold after water damage and, at the same time, under experimentally controlled conditions, test surfaces, contaminated with Aspergillus brasiliensis.

METHOD

After the nebulizer was used in two rooms with a massive mold infestation, the air colony count was determined (MAS-100(®) Zinsser Analytik) and, at the same time, the mold infestation in samples of wall plaster.As part of this controlled study, test surfaces contaminated with Aspergillus brasiliensis were positioned vertically and horizontally in a test room. The effectiveness of the nebulization (5-6% H(2)O(2) for 2 hours) was tested on these surfaces according to EN 13697.

RESULTS

In a massive mold infestation resulting from water damage (worst case), an approximately 9-fold decrease in the mold content and an approximately 13-fold decrease in the number of colony-forming units (sum of the bacteria + fungi) could be detected in the room air immediately after the nebulizing was finished. Even in samples of wall and joint plaster, the molds were reduced, although to a distinctly lesser extent. By indoor nebulization of 5-6% H(2)O(2), A. brasiliensis was reduced >4 log on vertical and horizontal surfaces.

DISCUSSION

In rooms with a massive mold infestation, the ASP GLOSAIR(TM) 400 system is suitable for attaining a clear reduction in the fungal and bacterial room air load, lasting for a week. On vertical and horizontal surfaces, contaminated experimentally with A. brasiliensis, a reduction of >4 lg is achieved. As a load of 10(4) to 10(5) fungal spores is unlikely to occur on pre-cleaned surfaces, the GLOSAIR(TM) 400 can be considered a suitable complementary process for the substantial reduction of fungal contamination.

Results of a healthcare worker (HCW) survey on environmental awareness as an instrument for the preparation of an environmental report for the University Medicine Greifswald

BACKGROUND

Environmental reporting is increasingly important for medical facilities. Currently, hospitals can determine the content of an environmental report as they see fit.

OBJECTIVE

To examine the utility and scope of an employee survey as an instrument for the preparation of an environmental report at the University Hospital Greifswald.

METHOD

For this purpose a questionnaire was developed with a focus on environmental behaviour and the significance attached to the protection of the environment.

RESULTS

The employees of the University Medicine Greifswald attach an unexpectedly high significance to the protection of the environment. Based on this finding, this potential should be used to promote the optimal implementation of ecological-economic behaviour within the University Medicine.

CONCLUSION

An employee survey is a useful instrument in the preparation of an environmental report.

Are laptop ventilation-blowers a potential source of nosocomial infections for patients?

Inadequately performed hand hygiene and non-disinfected surfaces are two reasons why the keys and mouse-buttons of laptops could be sources of microbial contamination resulting consequently in indirect transmission of potential pathogens and nosocomial infections. Until now the question has not been addressed whether the ventilation-blowers in laptops are actually responsible for the spreading of nosocomial pathogens. Therefore, an investigational experimental model was developed which was capable of differentiating between the microorganisms originating from the external surfaces of the laptop, and from those being blown out via the ventilation-blower duct. Culture samples were taken at the site of the external exhaust vent and temperature controls were collected through the use of a thermo-camera at the site of the blower exhaust vent as well as from surfaces which were directly exposed to the cooling ventilation air projected by the laptop. Control of 20 laptops yielded no evidence of microbial emission originating from the internal compartment following switching-on of the ventilation blower. Cultures obtained at the site of the blower exhaust vent also showed no evidence of nosocomial potential. High internal temperatures on the inner surfaces of the laptops (up to 73°C) as well as those documented at the site of the blower exhaust vent (up to 56°C) might be responsible for these findings.

Can physical stress be measured in urine using the parameter antioxidative potential?

Although regular exercise is known to promote health, it is also well known that competetive sports can lead to an increase of free radical production, and thus to a drop in antioxidative potential. Thus, the present study examined the effect of competetive sports on the antioxidative potential (AOP).

Using chemoluminescence, the AOP was measured in the spontaneous urine of leisure and semi-professional athletes during a training camp. Further, the parameters creatinin and uric acid were measured.

It was shown that physical stress led to a drop in the antioxidant potential of up to approximately 50%. To compensate for this decline, special antioxidant food is recommended.

Impact of surface disinfection and sterile draping of furniture on room air quality in a cardiac procedure room with a ventilation and air-conditioning system (extrusion airflow, cleanroom class 1b (DIN 1946-4))

In a cardiac procedure room, ventilated by a ventilation and air-conditioning system with turbulent mixed airflow, a protection zone in the operating area could be defined through visualization of airflows. Within this protection zone, no turbulence was detectable in the room air.Under the given conditions, disinfection of all surfaces including all furniture and equipment after the last operation and subsequent draping of furniture and all equipment that could not be removed from the room with sterile surgical drapes improved the indoor room air quality from cleanroom class C to cleanroom class B. This also allows procedures with elevated requirements to be performed in room class 1b.

Urinary iodide excretion in adults in germany 2005 meets WHO target

BACKGROUND

Recent regional and germanwide investigations have shown that the abolition of the requirement to declare iodine in foodstuffs and the greater emphasis on information about goitre prevention led to an increase in urinary iodine excretion in German schoolchildren. There was also a decrease in thyroid size and goitre prevalence in children. No up to date results in adults for the whole of Germany are available.

METHODS

In 2005 we examined the urinary iodine excretion in the spontaneous morning urine of 1 538 healthy adults in 357 places from all over Germany. The iodine was measured by the Cer- arsenit method.

RESULTS

The median iodine excretion amounted to 132 microg/l. There were no significant differences between age groups, sexes or regions. 64% had no iodine deficiency (>100 microg/l). In 23% the deficiency was slight (50-99 microg/l), in 10% moderate (20-49 microg/l) and in 3% there was severe iodine deficiency (<20 microg/l). 29% excreted >200 microg iodide per litre urine.

CONCLUSION

According to the WHO guidelines, there is no longer an iodine deficiency in German adults.

Effect of lactoperoxidase on the antimicrobial effectiveness of the thiocyanate hydrogen peroxide combination in a quantitative suspension test

BACKGROUND

The positive antimicrobial effects of increasing concentrations of thiocyanate (SCN-) and H2O2 on the human peroxidase defence system are well known. However, little is known about the quantitative efficacy of the human peroxidase thiocyanate H2O2 system regarding Streptococcus mutans and sanguinis, as well as Candida albicans. The aim of this study was to evaluate the effect of the enzyme lactoperoxidase on the bactericidal and fungicidal effectiveness of a thiocyanate-H2O2 combination above the physiological saliva level. To evaluate the optimal effectiveness curve, the exposure times were restricted to 1, 3, 5, and 15 min.

RESULTS

The bactericidal and fungicidal effects of lactoperoxidase on Streptococcus mutans and sanguinis and Candida albicans were evaluated by using two test mixtures of a 2.0% (w/v; 0.34 M) thiocyanate and 0.4% (w/v; 0.12 M) hydrogen peroxide solution, one without and one with lactoperoxidase. Following the quantitative suspension tests (EN 1040 and EN 1275), the growth of surviving bacteria and fungi in a nutrient broth was measured. The reduction factor in the suspension test without lactoperoxidase enzyme was < 1 for all three tested organisms. Thus, the mixtures of 2.0% (w/v; 0.34 M) thiocyanate and 0.4% (w/v; 0.12 M) hydrogen peroxide had no in vitro antimicrobial effect on Streptococcus mutans and sanguinis or Candida albicans. However, the suspension test with lactoperoxidase showed a high bactericidal and fungicidal effectiveness in vitro.

CONCLUSION

The tested thiocyanate and H2O2 mixtures showed no relevant antimicrobial effect. However, by adding lactoperoxidase enzyme, the mixtures became not only an effective bactericidal (Streptococcus mutans and sanguinis) but also a fungicidal (Candida albicans) agent.

Improving adherence to surgical hand preparation

At present, no universal agreement on detailed practice for surgical hand preparation exists. In order to fill this gap, in 2002 a Franco-German recommendation for surgical hand preparation was published as a first step towards a generally accepted European recommendation. Based on an assessment of the actual literature, a protocol for surgical hand preparation is discussed with the aim to recommend evidence-based standard procedures including prerequisites, washing and disinfection phase, and its practical implementation. In contrast to hygienic hand disinfection, for surgical hand preparation compliance is not an issue, since it mostly is regarded as a ceremony which is carried out without exception. Nevertheless, the following factors influence acceptance and efficacy: skin tolerance, ease of use, duration of procedure, and recommended time), potential for impaired efficacy due to incorrect performance of the procedure, possibility of systemic risks and irritating potential by applied preparations, religious restrictions, ecological aspects, costs and safety. Here, we report our experience with the introduction of a new hand preparation regime in all surgical disciplines in our university hospital based on the above factors. The following statements were evaluated: 1) The immediate efficacy of an alcohol-based hand disinfectant is impaired by a preceding hand wash for up to 10 minutes. Therefore hands should not be routinely washed before the disinfection period unless there is a good reason for it such as visible soiling. 2) A shortened application time (1.5 minutes) is equal to 3 min in terms of efficacy. 3) Hands should be air dried before gloves are put on, otherwise the perforation rate of gloves will increase. 4) The efficacy of alcohol-based disinfectants is significantly higher when hands are allowed to dry for 1 minute after the washing phase and before the disinfection phase. To clarify the above questions before the establishment of the modified technique, the surgical team was invited to a meeting. As a result, the heads of surgical departments supported the new technique and decided to change their practice.

Smoking as a risk factor for thyroid volume progression and incident goiter in a region with improved iodine supply

OBJECTIVE

The role of smoking in the pathogenesis of thyroid enlargement is currently under debate. It has been hypothesized that the effect of smoking on increased thyroid volume is larger in regions with than in regions without iodine deficiency. The aim of this paper was to investigate the association of smoking with thyroid volume progression and incident goiter for different age-strata in a region with improved iodine supply.

DESIGN AND METHODS

The population-based Study of Health in Pomerania compromised 3300 subjects with complete 5-year examination follow-up. Data from 2484 participants without known history of thyroid disorder or thyroid medication were analyzed. Thyroid size was evaluated by ultrasound. Determinants of thyroid volume progression and incident goiter, i.e., newly occurred goiter between baseline and follow-up, were analyzed by linear and logistic regression respectively.

RESULTS

Participants aged 20-39 years who were current smokers at baseline and at follow-up had a lower risk of incident goiter (odds ratio: 0.33; 95% confidence interval (CI): 0.15; 0.71; P=0.005). In this subpopulation, age was inversely related to thyroid volume progression. In subjects aged 60-79 years, smoking at baseline and follow-up was a risk factor for thyroid volume progression (beta: 3.37; 95% CI: 0.84; 5.89; P=0.009). After exclusion of individuals who had actual goiter in ultrasound at baseline, this association disappeared.

CONCLUSION

We conclude that the inverse association between smoking and goiter in young adults and the lacking association of smoking with goiter and thyroid volume progression in adult non-goitrous subjects indicate that smoking has a declining impact on thyroid growth in the study region. Our findings mirror the improved iodine supply of Northeast Germany.

Evaluation of nitrate influence on thyroid volume of adults in a previously iodine-deficient area

OBJECTIVE

The aim of the present study was to analyze the influence of nitrate as a possible alimentary goitrogen on thyroid volume in a previously iodine-deficient area.

DESIGN

Population based cross-sectional epidemiologic survey.

PARTICIPANTS

Data of 3772 participants (20-79 years) of the Study of Health in Pomerania without diagnosed thyroid disorders were analyzed. EVALUATION AND MEASUREMENTS: The nitrate concentration in spot urine was determined by ion chromatography. High nitrate levels were defined as urine nitrate concentrations exceeding the 75th percentile for the investigated population. Thyroid structure and size were measured by ultrasound. Subjects were divided into two groups with absence or presence of high urine nitrate concentrations. Comparisons between groups were made using the chi(2)-test or the Student's t-test. Multivariable analyses were done by logistic regression and ANOVA (analysis of variance). Odds ratios and their 95% confidence intervals as well as adjusted means (standard error) were calculated.

RESULTS

In the whole population, the mean urine nitrate level was 53.1+/-0.8mg/l. The 75th percentile of urine nitrate concentrations was 69.0mg/l, indicating that the renal excretion of nitrate is at a low level. The proportion of goiter in subjects with and without high urine nitrate concentrations was 35.5% and 34.7%, respectively (p=0.69). Analyses considering age, sex and further potential confounders could not identify an association between the exposure variable and the risk of goiter.

CONCLUSION

The low level of the alimentary nitrate intake does not influence the thyroid volume in a population with currently sufficient alimentary intake of iodine.

Quantity of ethanol absorption after excessive hand disinfection using three commercially available hand rubs is minimal and below toxic levels for humans

Background

Despite the increasing promotion of alcohol-based hand rubs and the worldwide use of ethanol-based hand rubs in hospitals only few studies have specifically addressed the issue of ethanol absorption when repeatedly applied to human skin. The aim of this study was to assess if ethanol absorption occurs during hygienic and surgical hand disinfection using three different alcohol-based hand-rubs, and to quantify absorption levels in humans.

Methods

Twelve volunteers applied three hand-rubs containing 95% (hand-rub A), 85% (hand-rub B) and 55% ethanol (hand-rub C; all w/w). For hygienic hand disinfection, 4 mL were applied 20 times for 30 s, with 1 minute break between applications. For surgical hand disinfection, 20 mL of each hand rub was applied to hands and arms up to the level of the elbow 10 times for 3 minutes, with a break of 5 minutes between applications. Blood concentrations of ethanol and acetaldehyde were determined immediately prior and up to 90 minutes after application using head space gas chromatography.

Results

The median of absorbed ethanol after hygienic hand disinfection was 1365 mg (A), 630 mg (B), and 358 mg (C). The proportion of absorbed ethanol was 2.3% (A), 1.1% (B), and 0.9% (C). After surgical hand disinfection, the median of absorbed ethanol was 1067 mg (A), 1542 mg (B), and 477 mg (C). The proportion of absorbed ethanol was 0.7% (A), 1.1% (B), and 0.5% (C). The highest median acetaldehyde concentration after 20 hygienic hand disinfections was 0.57 mg/L (hand-rub C, after 30 min), after 10 surgical hand disinfections 3.99 mg/L (hand-rub A, after 20 minutes).

Conclusion

The overall dermal and pulmonary absorption of ethanol was below toxic levels in humans and allows the conclusion that the use of the evaluated ethanol-based hand-rubs is safe.

Prospective study to determine the penetration of iodide into the anterior chamber following preoperative application of topical 1.25% povidone-iodine

BACKGROUND

Povidone-iodine is currently the agent of choice for pre-operative antisepsis in ophthalmology. Due to experimental and analytical constraints, iodine absorption into the anterior chamber (AC) has not yet been studied. However, knowledge of the details of iodine transfer into the aqueous humor (AH) is critical for risk assessment of local and/or systemic side effects

METHODS

Following a 2-min antisepsis with 1.25% povidone-iodine, the AC of eligible cataract patients was penetrated with a 26-gauge cannula prior to any other intraocular manipulation. To distinguish between the iodine absorbed into the AC and that remaining in the hypodermic delivery syringe, we studied three different groups of specimens: (i) AH from the AC (n=19); (ii) Ringer's solution aspirated through the cannula after penetration into and immediate withdrawal from the AC without subsequent decontamination (n=8); and (iii) Ringer's solution aspirated through the cannula after penetration into and immediate withdrawal from the AC, and subsequent decontamination of its outer surface (n=5). Patients with pre-operative epithelial defects were excluded from the study. To measure iodine absorption, iodide levels in samples were determined chromatographically (ion-pair chromatography) and electrochemically (gold electrode).

RESULTS

There was no difference (P=0.815) between detectable amounts of iodide in groups I and II (median: 24.0 microg/dl and 28.9 microg/dl, respectively). Only group III (median: 5.2 microg/dl) showed a statistically significant lower level of iodide than did groups I or II (P=0.019 and P=0.011, respectively).

CONCLUSIONS

A healthy ocular surface behaves as a barrier to the penetration of iodine into the AC. Any detectable iodide in the AH after antisepsis should therefore be considered harmless.

Thyroid disorders in employees of a nuclear power plant

BACKGROUND

The thyroid gland is a potential target organ for radiation-related damage. The aim of this analysis was to investigate the association between occupational exposure to ionizing radiation and the risk of autoimmune thyroid disease as well as thyroid nodules and dysfunction in workers of a former nuclear power station.

METHODS

Seventy-one male power station workers 38 to 57 years of age who had been exposed to a lifetime dose in the upper allowed range (accumulated lifetime dose 70 to 400 mSv) were compared to a population-based sample of 670 males who were not exposed to occupational radiation. Thyroid ultrasound was performed by the same observers. Laboratory parameters were analyzed in a central laboratory.

RESULTS

After controlling analyses for age and further relevant confounders no significant differences with respect to thyroid nodules and markers of autoimmune thyroid disease were detected between exposed and nonexposed individuals. However, nuclear power plant employees had higher odds for elevated serum thyrotropin (TSH) levels than the reference group (odds ratio 4.54; 95% confidence interval 1.43; 13.91).

CONCLUSIONS

Workers of a nuclear power plant with occupational exposure to ionizing radiation within the upper allowed dose range have an increased risk of elevated serum TSH levels. Further studies are required to confirm possible effects of occupational exposure to radiation on thyroid function.

Effect of topical 1.25% povidone-iodine eyedrops used for prophylaxis of ophthalmia neonatorum on renal iodine excretion and thyroid-stimulating hormone level

The 1% silver nitrate, which has been used for preventing gonococcal conjunctivitis in the neonate, is not effective against Chlamydia trachomatis and may provoke eye irritation. It is not known whether the alternative topical agent, 1.25% povidone-iodine, can influence thyroid function. In this study, no influence of povidone-iodine on thyroid function was observed.

Systemic Iodine Absorption after Preoperative Antisepsis Using Povidone-Iodine in Cataract Surgery – An Open Controlled Study

After preoperative conjunctival and periorbital antisepsis with povidone-iodine (PVP-I), the systemic absorption of iodine after cataract surgery was measured to evaluate the risk of thyroid side effects. Five different combinations of PVP-I alone or in combination with PVP-I-free antiseptics were applied to the conjunctiva and periorbital skin. An iodine-free product served as control. Iodide and creatinine in urine were analyzed before intervention and 24 and 48 h postoperatively. Depending on the concentration and application site, 0.3-4.5% of the total applied iodine or 3.6-45.4% of the free iodine were absorbed. The range of urine iodine excretion was between 11.7 and 71.0 mug iodine/g creatinine, depending on the PVP-I concentration and the site of application. The increase in iodine excretion was significant at 24 h postoperatively in trials receiving PVP-I both periorbitally and conjunctivally, depending of the concentration used. Because the iodine absorption is only slight and of doubtful clinical relevance, presurgical conjunctival antisepsis can be achieved with 1.25% PVP-I; so far clinically manifest anamnestic thyroid disorders are excluded. Presently, periorbital skin antisepsis with PVP-I cannot be recommended until data on thyroid metabolism in the population have been collected and evaluated, especially in a region currently or previously deficient in iodine.

The role of thiocyanate in the etiology of goiter in an industrial metropolitan area

OBJECTIVE

Thiocyanate (SCN-) has concentration dependent antithyroid properties and a role in the etiology of goiter has been suggested in several studies. In 1991 an epidemiological survey conducted in the region of Halle/Leipzig (Saxony), an area with significant air pollution, suggested an inverse relationship between urinary iodine (I-)/SCN- excretion and goiter prevalence. 10 years later, we reinvestigated the same industrial area to clarify if the situation has changed after the elimination of most industrial waste products and moreover, if SCN- excretion levels alone or in combination with air pollution or smoking as a SCN- source are critical for thyroid function.

DESIGN AND METHODS

We investigated a cohort of 708 probands for I-, SCN- and creatinine excretion in spot urine samples and determined the prevalence of goiter and thyroid nodules by high resolution ultrasonography.

RESULTS

Probands with goiter (n = 79, 11%) had significantly higher urinary SCN- excretions than probands without (3.9 +/- 2.8 vs 3.1 +/- 3.4 mg SCN-/g creatinine) and significantly lower urinary I-/SCN- ratios than patients without thyroid disorders (41 +/- 38 vs 61 +/- 71 microg I-/mg SCN-/l). Mean urinary I- excretions were not different between probands with or without goiter. Smokers showed significantly elevated urinary SCN-/creatinine ratios in comparison to non-smokers (4.3 +/- 4.3 vs 2.4 +/- 2.1 mg SCN-/g creatinine). ANOVA revealed a prediction of thyroid volume through age (P < 0.001), gender (P < 0.001), body weight (P < 0.05) and smoking (P < 0.05).

CONCLUSIONS

In our investigation, age, gender and smoking (raising SCN- levels by CN- inhalation) were predictive for thyroid volume and the urinary I-/SCN- ratios were able to detect probands with an increased risk of developing goiter in contrast to urinary I- excretion levels alone. These data suggest, that in an era and area of decreased cyanide pollution, SCN- may remain a cofactor in the multifactorial aetiology of goiter.