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Background: The Omicron variant of SARS-CoV-2 has a predilection for the upper airways, causing symptoms such as sore throat, hoarse voice, and stridor., Objective: We describe a series of children with COVID-19-associated croup in an urban multicenter hospital system., Methods: We conducted a cross-sectional study of children ≤18 years of age presenting to the emergency department during the COVID-19 pandemic. Data were extracted from an institutional data repository comprised of all patients who were tested for SARS-CoV-2. We included patients with a croup diagnosis by International Classification of Diseases, 10th revision code and a positive SARS-CoV-2 test within 3 days of presentation. We compared demographics, clinical characteristics, and outcomes for patients presenting during a pre-Omicron period (March 1, 2020-December 1, 2021) to the Omicron wave (December 2, 2021-February 15, 2022)., Results: We identified 67 children with croup, 10 (15%) pre-Omicron and 57 (85%) during the Omicron wave. The prevalence of croup among SARS-CoV-2-positive children increased by a factor of 5.8 (95% confidence interval 3.0-11.4) during the Omicron wave compared to prior. More patients were ≥6 years of age in the Omicron wave than prior (19% vs. 0%). The majority were not hospitalized (77%). More patients ≥6 years of age received epinephrine therapy for croup during the Omicron wave (73% vs. 35%). Most patients ≥6 years of age had no croup history (64%) and only 45% were vaccinated against SARS-CoV-2., Conclusion: Croup was prevalent during the Omicron wave, atypically affecting patients ≥6 years of age. COVID-19-associated croup should be added to the differential diagnosis of children with stridor, regardless of age. © 2022 Elsevier Inc., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Background: The assessment of thermal burn depth remains challenging. Over the last decades, several optical systems were developed to determine burn depth. So far, only laser doppler imaging (LDI) has been shown to be reliable while others such as infrared thermography or spectrophotometric intracutaneous analysis have been less accurate. The aim of our study is to evaluate hyperspectral imaging (HSI) as a new optical device., Methods: Patients suffering thermal trauma treated in a burn unit in Germany between November 2019 and September 2020 were included. Inclusion criteria were age ≥18 years, 2 nd or 3 rd degree thermal burns, written informed consent and presentation within 24 h after injury. Clinical assessment and hyperspectral imaging were performed 24, 48 and 72 h after the injury. Patients in whom secondary wound closure was complete within 21 days (group A) were compared to patients in whom secondary wound closure took more than 21 days or where skin grafting was indicated (group B). Demographic data and the primary parameters generated by HSI were documented. A Mann Whitney-U test was performed to compare the groups. A p-value below 0.05 was considered to be statistically significant. The data generated using HSI were combined to create the HSI burn index (BI). Using a logistic regression and receiver operating characteristics curve (ROC) sensitivity and specificity of the BI were calculated. The trial was officially registered on DRKS (registration number: DRKS00022843)., Results: Overall, 59 patients with burn wounds were eligible for inclusion. Ten patients were excluded because of a poor data quality. Group A comprised 36 patients with a mean age of 41.5 years and a mean burnt body surface area of 2.7%. In comparison, 13 patients were allocated to group B because of the need for a skin graft (n = 10) or protracted secondary wound closure lasting more than 21 days. The mean age of these patients was 46.8 years. They had a mean affected body surface area of 4.0%. 24, 48, and 72 h after trauma the BI was 1.0 ± 0.28, 1.2 ± 0.29 and 1.55 ± 0.27 in group A and 0.78 ± 0.14, 1.05 ± 0.23 and 1.23 ± 0.27 in group B. At every time point significant differences were demonstrated between the groups. At 24 h, ROC analysis demonstrated BI threshold of 0.95 (sensitivity 0.61/specificity 1.0), on the second day of 1.17 (sensitivity 0.51/specificity 0.81) and on the third day of 1.27 (sensitivity 0.92/specificity 0.71)., Conclusion: Changes in microcirculation within the first 72 h after thermal trauma were reflected by an increasing BI in both groups. After 72 h, the BI is able to predict the need for a skin graft with a sensitivity of 92% and a specificity of 71%., (Copyright © 2021 Elsevier Ltd and ISBI. All rights reserved.)

Pelagic Sargassum species have been known for centuries in the Sargasso Sea of the North Atlantic Ocean. In 2011, a new area concentrating high biomass of these brown algae started developing in the Tropical Atlantic Ocean. Since then, massive and recurrent Sargassum influxes have been reported in the Caribbean and off the coast of Western Africa. These Sargassum events have a major negative impact on coastal ecosystems and nearshore marine life, and affect socio-economic sectors, including public health, coastal living, tourism, fisheries, and maritime transport. Despite recent advances in the forecasting of Sargassum events, and elucidation of the seaweed composition, many knowledge gaps remain, including morphotype abundance during Sargassum events, drift of the seaweeds in the months prior to stranding, and influence of sample processing methods on biomass biochemical composition. Using seaweeds harvested on the coasts of Jamaica in summer of 2020, we observed that S. fluitans III was the most abundant morphotype at different times and sampling locations. No clear difference in the geographical origin, or provenance, of the Sargassum mats was observed. The majority of Sargassum backtracked from both north and south of Jamaica experienced ambient temperatures of around 27 °C and salinity in the range of 34-36 psu before stranding. We also showed that cheap (sun) compared to expensive (freeze) drying techniques influence the biochemical composition of biomass. Sun-drying increased the proportion of phenolic compounds, but had a deleterious impact on fucoxanthin content and on the quantities of monosaccharides, except for mannitol. Effects on the content of fucose containing sulfated polysaccharides depended on the method used for their extraction, and limited variation was observed in ash, protein, and fatty acid content within most of the sample locations investigated. These observations are important for the storage and transport of the biomass in the context of its valorisation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

In addition to a conventional relaxed state, a fraction of myosins in the cardiac muscle exists in a low-energy consuming super-relaxed (SRX) state, which is kept as a reserve pool that may be engaged under sustained increased cardiac demand. The conventional relaxed and the super-relaxed states are widely assumed to correspond to a structure where myosin heads are in an open configuration, free to interact with actin, and a closed configuration, inhibiting binding to actin, respectively. Disruption of the myosin SRX population is an emerging model in different heart diseases, such as hypertrophic cardiomyopathy, which results in excessive muscle contraction, and stabilizing them using myosin inhibitors is budding as an attractive therapeutic strategy. Here we examined the structure-function relationships of two myosin ATPase inhibitors, mavacamten and para-nitroblebbistatin, and found that binding of mavacamten at a site different than para-nitroblebbistatin populates myosin into the SRX state. Para-nitroblebbistatin, binding to a distal pocket to the myosin lever arm near the nucleotide-binding site, does not affect the usual myosin SRX state but instead appears to render myosin into a new, perhaps much more inhibited, 'ultra-relaxed' state. X-ray scattering-based rigid body modeling shows that both mavacamten and para-nitroblebbistatin induce novel conformations in human β-cardiac heavy meromyosin that diverge significantly from the hypothetical open and closed states, and furthermore, mavacamten treatment causes greater compaction than para-nitroblebbistatin. Taken together, we conclude that mavacamten and para-nitroblebbistatin stabilize myosin in different structural states, and such states may give rise to different functional energy-sparing states., Competing Interests: Declaration of interests SKG, NS, and SN are all employees of MyoKardia, Inc, a wholly-owned subsidiary of Bristol Myers Squibb (TM), and hold company shares through their employment. The authors declare that they have no conflicts of interest with the contents of this article., (Copyright © 2021 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Background: Deep sternal wound infection remains a serious complication after cardiac surgery, leading to increased morbidity, mortality, and cost. The goal of our study was to develop a standardized, reproducible method to safely cover deep sternal wounds and ensure improved healing rates., Methods: The study was developed as a retrospective cohort study. We included 58 patients who received standardized latissimus dorsi flap coverage of a sternum defect wound after poststernotomy mediastinitis at our institution between September 2015 and June 2017., Results: The average age of the cohort was 66.75 years, and 51.72% of patients were men. The mean hospital stay was 26.83 days. Eight patients (14.75%) died during the hospital stay due to sepsis or heart failure. The average flap size was 137.13 cm 2 . The mean operative time was 155 minutes. Seventy-four percent of patients developed a seroma at the donor site, which was treated conservatively with compression garments and taps, and 7% of patients developed a wound dehiscence of the donor site, which was treated conservatively with dressings. The mean follow-up time was 15 weeks. All 50 surviving patients showed complete wound healing on follow-up., Conclusions: The latissimus dorsi pedicled flap is a safe, reproducible technique for coverage of deep sternal wounds, with few relevant perioperative complications. By setting definite parameters for the flap dissection and by ensuring a reliable blood supply, our method enables the coverage of these complex wounds by an interdisciplinary team in any cardiovascular surgical setting., (Copyright © 2019 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Trauma to the perineum, levator ani complex, and anal sphincter is common during vaginal childbirth, but often clinically underdiagnosed, and many women are unaware of the potential for long-term damage., Objective: In this study we use transperineal ultrasound to identify how many women will achieve a normal vaginal delivery without substantial damage to the levator ani or anal sphincter muscles, and to create a model to predict patient characteristics associated with successful atraumatic normal vaginal delivery., Study Design: This is a retrospective, secondary analysis of data sets gathered in the context of an interventional perinatal imaging study. A total of 660 primiparas, carrying an uncomplicated singleton pregnancy, underwent an antepartum and postpartum interview, vaginal exam (Pelvic Organ Prolapse Quantification), and 4-dimensional translabial ultrasound. Ultrasound data were analyzed for levator trauma and/or overdistention and residual sphincter defects. Postprocessing analysis of ultrasound volumes was performed blinded against clinical data and analyzed against obstetric data retrieved from the local maternity database. Levator avulsion was diagnosed if the muscle insertion at the inferior pubic ramus at the plane of minimal hiatal dimensions and within 5 mm above this plane on tomographic ultrasound imaging was abnormal, ie the muscle was disconnected from the inferior pubic ramus. Hiatal overdistensibility (microtrauma) was diagnosed if there was a peripartum increase in hiatal area on Valsalva by >20% with the resultant area ≥25 cm 2 . A sphincter defect was diagnosed if a gap of >30 degrees was seen in ≥4 of 6 tomographic ultrasound imaging slices bracketing the external anal sphincter. Two models were tested: a first model that defines severe pelvic floor trauma as either obstetric anal sphincter injury or levator avulsion, and a second, more conservative model, that also included microtrauma., Results: A total of 504/660 women (76%) returned for postpartum follow-up as described previously. In all, 21 patients were excluded due to inadequate data or intercurrent pregnancy, leaving 483 women for analysis. Model 1 defined nontraumatic vaginal delivery as excluding operative delivery, obstetric anal sphincter injuries, and sonographic evidence of levator avulsion or residual sphincter defect. Model 2 also excluded microtrauma. Of 483 women, 112 (23%) had a cesarean delivery, 103 (21%) had an operative vaginal delivery, and 17 (4%) had a third-/fourth-degree tear, leaving 251 women who could be said to have had a normal vaginal delivery. On ultrasound, in model 1, 27 women (6%) had an avulsion and 31 (6%) had a residual defect, leaving 193/483 (40%) who met the criteria for atraumatic normal vaginal delivery. In model 2, an additional 33 women (7%) had microtrauma, leaving only 160/483 (33%) women who met the criteria for atraumatic normal vaginal delivery. On multivariate analysis, younger age and earlier gestation at time of delivery remained highly significant as predictors of atraumatic normal vaginal delivery in both models, with increased hiatal area on Valsalva also significant in model 2 (all P ≤ .035)., Conclusion: The prevalence of significant pelvic floor trauma after vaginal child birth is much higher than generally assumed. Rates of obstetric anal sphincter injury are often underestimated and levator avulsion is not included as a consequence of vaginal birth in most obstetric text books. In this study less than half (33-40%) of primiparous women achieved an atraumatic normal vaginal delivery., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Background: Surgical site infections (SSIs) of the groin remain a crucial problem in vascular surgery, prompting great interest in preventative techniques, such as closed incision negative pressure therapy (ciNPT). This prospective randomised study aimed to assess the potential benefits of ciNPT application after groin incisions for vascular surgery., Method: The study included 204 patients who underwent vascular surgery for peripheral artery disease (PAD) at two sites between July 2015 and May 2017. These patients received post-operative treatment with ciNPT (intervention group) or standard wound dressings (control group). After exclusion, 188 patients were assessed for SSIs using the Szilagyi classification., Results: The mean patient age was 66.6 ± 9.4 years (range 43-85 years), and 70% were male (n = 132). Regarding PAD stage, 52% were stage IIB, 28% stage III, and 19% stage IV. Among the patients, 45% (n = 85) had had a previous groin incision. Bacterial swabs were performed in each case of suspected SSI (22.8% [43/188]), while 76.7% (33/188) were negative, there were 5% [5/98] positive swabs in the intervention group and 5.5% [5/90] in the control group). Antibiotics were given to 13.2% of the intervention group, and 31.1% of the control group (p = .004). The control group experienced more frequent SSIs (33.3%; 30/90) than the intervention group (13.2%; 13/98; p = .0015; absolute risk difference -20.1 per 100; 95% CI -31.9 to 8.2). This difference was based on an increased rate of Szilagyi I SSI in the control group (24.6% vs. 8.1%, p = .0012)., Conclusion: The results confirmed a reduced superficial SSI rate after vascular surgical groin incision using ciNPT compared with standard wound dressings., (Copyright © 2018 European Society for Vascular Surgery. Published by Elsevier B.V. All rights reserved.)

Arteriovenous fistula (AVF) is the common vascular access type for a hemodialysis patient. Its failure is due to neointimal hyperplasia. Vitamin K antagonists are given to lower thrombosis tendency, but have side effects that enhance arterial calcifications. Here, we investigated the effects of vitamin K antagonists and vitamin K2 (K2) treatment on neointimal hyperplasia development and calcification in rats and in arterialized human veins. AVF was generated in female rats while chronic kidney disease (CKD) was induced using an adenine-enriched diet. Arterialization, CKD, and vitamin K antagonists all significantly enhanced venous neointimal hyperplasia. K2 treatment, additional to vitamin K antagonists, significantly reduced neointimal hyperplasia in arterialized veins in healthy rats but not in rats with CKD. Arterialization, CKD, and vitamin K antagonism all significantly increased, whereas K2 supplementation attenuated calcification in healthy rats and rats with CKD. K2 significantly enhanced matrix Gla protein carboxylation in control rats and rats with CKD. Arterialized human vein samples contained inactive matrix Gla protein at calcification and neointimal hyperplasia sites, indicating local vitamin K deficiency. Thus, vitamin K antagonists have detrimental effects on AVF remodeling, whereas K2 reduced neointimal hyperplasia and calcification indicating vasoprotective effects. Hence, K2 administration may be useful to prevent neointimal hyperplasia and calcification in arterialized veins

Glucokinase plays a key role in glucose sensing in pancreatic beta cells and in liver metabolism. Heterozygous inactivating glucokinase mutations cause the autosomal dominantly inherited MODY2 subtype of maturity-onset diabetes of the young. The goal of this study was to elucidate the pathogenicity of the recently described glucokinase mutants L304P and L315H, located in an alpha-helix and connecting region, respectively, at the outer region of the large domain of glucokinase. Both mutants showed wild-type-like cytosolic localization, but faster protein degradation in insulin-secreting MIN6 cells. However, strongly reduced nuclear/cytoplasmic localization of the mutants was observed in primary hepatocytes suggesting reduced interaction with the liver specific glucokinase regulatory protein. Both mutants displayed a significantly lowered glucokinase activity compared to the wild-type protein. Even though the L315H protein showed the lowest enzymatic activity, this mutant was very sensitive to allosteric activation. The endogenous activator fructose-2,6-bisphosphatase evoked an increase in glucokinase activity for both mutants, but much stronger for L315H compared to L304P. The synthetic activator RO281675 was ineffective against the L304P mutant. Expression of the mutant proteins evoked loss of glucose-induced insulin secretion in MIN6 cells. Administration of RO281675 increased insulin secretion, however, only for the L315H mutant. Thus, a glucokinase activator drug therapy may help MODY2 patients not in general, but seems to be a useful strategy for carriers of the L315H glucokinase mutation., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Two cases of acute babesiosis in captive reindeer (Rangifer tarandus) in two German zoos in 2009 and 2012 triggered this study to investigate the occurrence and species diversity of Babesia parasites infecting reindeer in different zoos and deer parks in Germany. Between June and December 2013, blood samples were taken from 123 clinically inapparent reindeer from 16 different facilities. Samples were tested for the presence of Babesia species DNA by conventional PCR and sequence analysis of part of the 18S rRNA gene. Also, Giemsa-stained smears of reindeer blood samples were examined for parasitaemia by light microscopy. The overall PCR-prevalence in blood samples was 23.6% (n=29). Comparison of sequenced amplicons with GenBank entries possibly revealed up to five different Babesia species: B. venatorum (n=19), B. capreoli (n=2) and B. capreoli-like (n=4), B. odocoilei-like (n=2) and B. divergens (n=1), while one sample turned out to be a Theileria sp. Out of the 16 facilities in the study, 12 housed at least one positive animal. In Giemsa-stained blood smears, intra-erythrocytic Babesia parasites were detected in samples of three reindeer from three locations. The high prevalence of Babesia infections implicates babesiosis to be a relevant infectious disease threat for captive reindeer in Germany. Consequently, reindeer with clinical signs compatible to those of acute babesiosis should either be tested for the presence of Babesia spp. DNA or blood smears should be examined for parasitaemia., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Clostridium botulinum C2 toxin, Clostridium perfringens iota toxin and Clostridium difficile CDT belong to the family of binary actin ADP-ribosylating toxins and are composed of a binding/translocation component and a separate enzyme component. The enzyme components ADP-ribosylate G-actin in the cytosol of target cells resulting in depolymerization of F-actin, cell rounding and cell death. The binding/translocation components bind to their cell receptors and form complexes with the respective enzyme components. After receptor-mediated endocytosis, the binding/translocation components form pores in membranes of acidified endosomes and the enzyme components translocate through these pores into the cytosol. This step is facilitated by the host cell chaperone heat shock protein 90 and peptidyl-prolyl cis/trans isomerases including cyclophilin A. Here, we demonstrate that a large isoform of cyclophilin A, the multi-domain enzyme cyclophilin 40 (Cyp40), binds to the enzyme components C2I, Ia and CDTa in vitro. Isothermal titration calorimetry revealed a direct binding to C2I with a calculated affinity of 101 nM and to Ia with an affinity of 1.01 μM. Closer investigation for the prototypic C2I revealed that binding to Cyp40 did not depend on its ADP-ribosyltransferase activity but was stronger for unfolded C2I. The interaction of C2I with Cyp40 was also demonstrated in lysates from C2-treated cells by pull-down. Treatment of cells with a non-immunosuppressive cyclosporine A derivative, which still binds to and inhibits the peptidyl-prolyl cis/trans isomerase activity of cyclophilins, protected cells from intoxication with C2, iota and CDT toxins, offering an attractive approach for development of novel therapeutic strategies against binary actin ADP-ribosylating toxins., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Adipocyte hypertrophy and hyperplasia have been shown to be associated with shorter telomere length, which may reflect aging, altered cell proliferation and adipose tissue (AT) dysfunction. In individuals with obesity, differences in fat distribution and AT cellular composition may contribute to obesity related metabolic diseases. Here, we tested the hypotheses that telomere lengths (TL) are different between: (1) abdominal subcutaneous and omental fat depots, (2) superficial and deep abdominal subcutaneous AT (SAT), and (3) adipocytes and cells of the stromal vascular fraction (SVF). We further asked whether AT TL is related to age, anthropometric and metabolic traits. TL was analyzed by quantitative PCR in total human genomic DNA isolated from paired subcutaneous and visceral AT of 47 lean and 50 obese individuals. In subgroups, we analyzed TL in isolated small and large adipocytes and SVF cells. We find significantly shorter TL in subcutaneous compared to visceral AT (P < 0.001) which is consistent in men and subgroups of lean and obese, and individuals with or without type 2 diabetes (T2D). Shorter TL in SAT is entirely due to shorter TL in the SVF compared to visceral AT (P < 0.01). SAT TL is most strongly correlated with age (r = -0.205, P < 0.05) and independently of age with HbA1c (r = -0.5, P < 0.05). We found significant TL differences between superficial SAT of lean and obese as well as between individuals with our without T2D, but not between the two layers of SAT. Our data indicate that fat depot differences in TL mainly reflect shorter TL of SVF cells. In addition, we found an age and BMI-independent relationship between shorter TL and HbA1c suggesting that chronic hyperglycemia may impair the regenerative capacity of AT more strongly than obesity alone., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Studies in rodents indicate that phthalates can function as adjuvants, increasing the potency of allergens. Meanwhile, epidemiological studies have produced inconsistent findings regarding relationships between phthalate exposures and allergic disease in humans. The present study examined phthalate exposure and allergic sensitization in a large group of 3-5 year old children: 300 random controls and 200 cases with asthma, rhinoconjunctivitis or atopic dermatitis as reported in questionnaires. The children were clinically examined to confirm their health status. Blood samples were analyzed for IgE sensitization to 20 allergens. Adjusted logistic regressions were used to look for associations between phthalate exposure indicators (mass fractions in dust from children's homes and daycares, metabolites in urine, and estimated daily indoor intakes from dust ingestion, inhalation and dermal absorption) and sensitization and allergic disease. No direct associations were found between phthalate exposures and asthma, rhinoconjunctivitis or atopic dermatitis. However, among children with these diseases, there were significant associations between non-dietary exposures to DnBP, BBzP and DEHP in the indoor environment (mass fractions in dust or daily indoor intakes from dust ingestion, inhalation and dermal absorption) and allergic sensitization. Some exposure pathways were more strongly associated with sensitization than others, although the results are not conclusive and require confirmation. A number of the associations depended on accounting for a child's exposure in more than one environment (i.e., daycare facility as well as home). Significant associations were not observed between phthalate metabolites in urine, which reflected exposure from diet as well as indoor pathways, and allergic sensitization., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Water-soluble vitamins are an important class of compounds that require quantification from food sources to monitor nutritional value. In this study we have analysed six water-soluble B vitamins ([thiamine (B1), riboflavin (B2), nicotinic acid (B3, NAc), nicotinamide (B3, NAm), pyridoxal (B6), folic acid (B9)], and ascorbic acid (vit C) with hydrophilic interaction liquid chromatography (HILIC), and compared UV, fluorescent (FLD) and coulometric detection to optimise a method to quantitate the vitamins from food sources. Employing UV/diode array (DAD) and fluorimetric detection, six B vitamins were detected in a single run using gradient elution from 100% to 60% solvent B [10mM ammonium acetate, pH 5.0, in acetonitrile and water 95:5 (v:v)] over 18 min. UV detection was performed at 268 nm for B1, 260 nm for both B3 species and 284 nm for B9. FLD was employed for B2 at excitation wavelength of 268 nm, emission of 513 nm, and 284 nm/317 nm for B6. Coulometric detection can be used to detect B6 and B9, and vit C, and was performed isocratically at 75% and 85% of solvent B, respectively. B6 was analysed at a potential of 720 mV, while B9 was analysed at 600 mV, and vit C at 30 mV. Retention times (0.96 to 11.81 min), intra-day repeatability (CV 1.6 to 3.6), inter-day variability (CV 1.8 to 11.1), and linearity (R 0.9877 to 0.9995) remained good under these conditions with limits of detection varying from 6.6 to 164.6 ng mL(-1), limits of quantification between 16.8 and 548.7 ng mL(-1). The method was successfully applied for quantification of six B vitamins from a fortified food product and is, to our knowledge, the first to simultaneously determine multiple water-soluble vitamins extracted from a food matrix using HILIC., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Conjoined twinning is rare in man and non-human primates. The current report describes a case of ischiopagus tripus conjoined Western Lowland gorilla (Gorilla gorilla) twins. The female twins were joined at the umbilical and pelvic region, involving the liver, xiphoid, umbilicus, body wall and skin. Computed tomography revealed two complete spines. The combined pelvic space was formed by two sacra, each connected with two iliac bones. The twins were only conjoined by a common pubis. Cause of death was attributed to cardiac and circulatory collapse resulting from a large patent foramen ovale (8 mm in diameter) of one twin and neonatal asphyxia., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Objective: We aimed to explore how patients with long-term conditions choose between available healthcare options during a health crisis., Methods: Patients in North-West England with one or more of four long-term conditions were invited to take part in a questionnaire cohort study of healthcare use. Semi-structured interviews were conducted with a sub-sample of fifty consenting patients. Data were analysed qualitatively, using a framework approach., Results: Patients described using emergency care only in response to perceived urgent need. Their judgements about urgency of need, and their choices about what services to use were guided by previous experiences of care, particularly how accessible services were and the perceived expertise of practitioners., Conclusion: Recursivity and candidacy provide a framework for understanding patient decision-making around emergency care use. Patients were knowledgeable and discriminating users of services, drawing on experiential knowledge of healthcare to choose between services. Their sense of 'candidacy' for specific emergency care services, was recursively shaped by previous experiences., Practice Implications: Strategies that emphasise the need to educate patients about healthcare services use alone are unlikely to change care-seeking behaviour. Practitioners need to modify care experiences that recursively shape patients' judgements of candidacy and their perceptions of accessible expertise in alternative services., (Copyright © 2013 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.)

Objective: Extensive wounds of burn patients remain a challenge due to wound infection and subsequent septicemia. We wondered whether extracorporeal shock wave application (ESWA) accelerates the healing process. The aim of the study was to analyze microcirculation, angiogenesis and leukocyte endothelium interaction after burns by using ESWA with two types of low intensity., Methods: Full-thickness burns were inflicted to the ears of hairless mice (n=51; area: 1.3 mm(2)). The mice were randomized into five groups: (A) low-energy shock waves after burn injury (0.04 mJ/mm(2)); (B) very low-energy shock waves after burn injury (0.015 mJ/mm(2)); (C) mice received burns but no ESWA (control group); (D) mice without burn were exposed to low-energy shock waves; (E) mice without burns and with no shock wave application. Intravital fluorescent microscopy was used to assess microcirculatory parameters, angiogenesis and leukocyte behavior. ESWA was performed on day 1, 3 and 7 (500 shoots, 1 Hz). Values were obtained straight after and on days 1, 3, 7 and 12 post burn., Results: Group A showed accelerated angiogenesis (non-perfused area at day 12: 5.3% vs. 9.1% (group B) and 12.6% (group C), p=0.005). Both shock wave groups showed improved blood flow after burn compared to group C. Shock waves significantly increased the number of rolling leukocytes compared to the non-ESWA-treated animals (group D: 210.8% vs. group E: 83.3%, p=0.017 on day 7 and 172.3 vs. 90.9%, p=0.01 on day 12)., Conclusion: Shock waves have a positive effect on several parameters of wound healing after burns, especially with regard to angiogenesis and leukocyte behaviour. In both ESWA groups, angiogenesis and blood flow outmatched the control group. Within the ESWA groups the higher intensity (0.04 mJ/mm(2)) showed better results than the lower intensity group. Moreover, shock waves increased the number of rolling and sticking leukocytes as a part of an improved metabolism., (Copyright © 2012 Elsevier Ltd and ISBI. All rights reserved.)

Objective: The treatment of burns remains a challenge. Besides the administration of physiological saline, local disinfection and symptomatic medications, no causal therapy is known to accelerate angiogenesis and wound healing. The aim of this study was to investigate the influences of dilatative and anti-inflammatory acting drugs on microcirculation, angiogenesis and leukocyte behavior, which had shown positive effects in former burn studies., Methods: The ears of male hairless mice (n=47) were inflicted with full thickness burns using a hot air jet. Then the affects of five intraperitoneal injections of either acetylsalicylic acid (ASA), isosorbide dinitrate, prostaglandin E1 (PGE1) or sodium chloride (each administered to one of four corresponding study groups), on microcirculation, leukocyte-endothelial interaction and angiogenesis were investigated over a 12 day period using intravital fluorescent microscopy., Results: Angiogenesis was slightly improved by PGE1 (0.3 vs. 1.3% non-perfused area in other groups on day 12, p=0.029). Additionally, blood flow increased and rolling leukocytes decreased compared to other groups. The ASA-group showed best functional vessel density and lowest leukocyte-adhesion. The often described posttraumatic expansion of tissue damage could not be observed in either group., Conclusion: Prostaglandin E1 improved angiogenesis, increased the blood flow and reduced the number of rolling leukocytes. ASA had positive influences on functional vessel density, edema formation and the number of sticking leukocytes. However, it reduced the blood flow. Overall, out of all the drugs tested, prostaglandin seems to have the greatest positive impact on microcirculation and angiogenesis in burns., (Copyright © 2011 Elsevier Ltd and ISBI. All rights reserved.)

Purpose: To evaluate a cardiovascular magnetic resonance imaging (MRI) technique which allows the longitudinal analysis of cardiovascular remodeling in a rodent femoral arteriovenous fistula (AVF) model by means of a clinical scanner., Materials and Methods: Eight rats underwent femoral AVF surgery and four rats served as controls. Vascular and cardiac morphology as well as cardiac function was assessed from Week 3 to 12 using contrast-enhanced, time-resolved magnetic resonance angiography (MRA) and cardiac MRI (cine gradient-echo sequence) at 3 T in one imaging session., Results: Arteriovenous surgery resulted in progressive venous dilation and a subsequent cardiac adaptation. This procedure led to downstream vasodilation of the iliac vein and inferior vena cava of 179% and 188%, respectively (3 weeks). To accommodate the increased returning blood volume, cardiac output (CO) increased significantly (P=.014; 6 weeks). This was caused by increased end-diastolic volume (EDV), stroke volume (SV) and heart rate (HR) consistent with an increased volume load. A continuous increase in heart weight peaked at 12 weeks. This increase combined with a distinct end-diastolic left ventricular dilation implied eccentric hypertrophy., Conclusion: Small rodent MRI is feasible and clearly depicts fistula maturation and cardiac alterations. This technique proved to be a valuable tool for longitudinal in vivo monitoring in this model, which strongly resembles clinical findings in hemodialysis patients., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Purpose: The effect of cold low-pressure plasma treatment on neovascularization of a dermis substitute was evaluated in a mouse model., Material and Methods: Collagen-elastin matrices (Matriderm(®)) were used as scaffolds. Low-pressure argon/hydrogene plasma-treated scaffolds were transplanted into the dorsal skinfold chambers of balb/c mice (group 1, n=10). Untreated scaffolds served as controls (group 2, n=10). Intravital fluorescence microscopy was performed within the border zone of the scaffolds on days 1, 5 and 10. Functional vessel density (FVD), vessel diameter, intervascular distance, microvascular permeability, and leukocyte-endothelium interaction were analyzed., Results: An increase of FVD associated with a reduction of the intervascular distance was observed. Statistical analysis revealed that the functional vessel density in the border zone of the scaffolds was significantly enhanced in the plasma-treated group compared to controls. For group 1, an increase of FVD from 282±8 cm/cm(2) on days 5 to 315±8 cm/cm(2) on day 10 was observed. Whereas values of 254±7 cm/cm(2) on day 5 and 275±13 cm/cm(2) on day 10 have resulted in group 2 (mean±S.E.M., Student's t-test, p<0.05)., Conclusion: The surface treatment by cold low-pressure plasma intensifies the angiogenesis and accelerates the neovascularization of collagen-elastin matrix., (Copyright © 2010 Elsevier Ltd and ISBI. All rights reserved.)

Neointimal hyperplasia (NIH) and impaired dilatation are important contributors to arteriovenous fistula (AVF) failure. It is unclear whether chronic kidney disease (CKD) itself causes adverse remodeling in arterialized veins. Here we determined if CKD specifically triggers adverse effects on vascular remodeling and assessed whether these changes affect the function of AVFs. For this purpose, we used rats on a normal diet or on an adenine-rich diet to induce CKD and created a fistula between the right femoral artery and vein. Fistula maturation was followed noninvasively by high-resolution ultrasound (US), and groups of rats were killed on 42 and 84 days after surgery for histological and immunohistochemical analyses of the AVFs and contralateral femoral vessels. In vivo US and ex vivo morphometric analyses confirmed a significant increase in NIH in the AVFs of both groups with CKD compared to those receiving a normal diet. Furthermore, we found using histological evaluation of the fistula veins in the rats with CKD that the media shrank and their calcification increased significantly. Afferent artery dilatation was significantly impaired in CKD and the downstream fistula vein had delayed dilation after surgery. These changes were accompanied by significantly increased peak systolic velocity at the site of the anastomosis, implying stenosis. Thus, CKD triggers adverse effects on vascular remodeling in AVFs, all of which contribute to anatomical and/or functional stenosis.

Purpose: Plaque morphology is an important predictor of stroke risk and may also be a predictor of postoperative outcome after carotid endarterectomy (CEA). Thus, the purpose of our study was to evaluate the findings of preoperative dual-source computed tomography (DSCT) of carotid plaque morphology and correlate these findings with histopathological findings., Material and Methods: Thirty patients undergoing CEA due to neurological events and high-grade carotid artery stenosis were evaluated with DSCT for degree of stenosis following the North American Symptomatic Carotid Endarterectomy Trial (NASCET) criteria and for non-invasive plaque morphology prior to CEA. CT protocol was as follows (SOMATOM Definition, Siemens Medical Solutions, Forchheim, Germany): A dual-energy protocol was used with tube A (140 kV, 55 mA) and tube B (80 kV, 230 mA) with 2 x 64 x 0.6-mm collimation, pitch 0.65 and rotation time of 0.33 s. Histopathological work-up was performed on the surgically retrieved tissues. The findings from DSCT and histopathology were compared with respect to image quality and plaque composition (fatty plaque, mixed plaque and calcified plaque), were correlated with histological specimens and classified according to the American Heart Association (AHA) classification of atherosclerotic plaque. Pearson correlation and kappa statistics were performed., Results: The image quality of DSCT was rated as 'excellent' in all the examinations. The mean degree of stenosis was quantified as 82%. The sensitivity of DSCT for the detection of calcification was 100% (standard deviation (SD) 0%, confidence interval (CI): 99-100). While the sensitivity for the detection of mixed plaques was 89% (SD 12%, CI: 79-98), it was 85% (SD 10%, CI: 76-92) for the detection of low-density fatty plaques. The mean degree of agreement was k=0.81., Conclusion: DSCT angiography of the carotid arteries is feasible and the evaluation of carotid plaque composition allows non-invasive assessment of different plaque components. This may have an impact on the non-invasive differentiation of vulnerable plaques.

Objective: To test the diagnostic relevance of fast Gadobenate dimeglumine (Gd-BOPTA) enhanced, time-resolved, three-dimensional magnetic resonance angiography (t3D MRA) of distal calf and pedal vasculature in critical limb ischemia in a prospective comparison with conventional selective digital subtraction angiography (DSA) and high-resolution duplex ultrasound (US) scan., Methods: From April 2007 to June 2008, 34 feet of 29 consecutive patients suffering from limb-threatening ischemia underwent diagnostic US scan, DSA, and t3D MRA before treatment. The investigations took place within 3 days. A t3D MRA was performed using a 3 Tesla whole-body magnetic resonance (MR) system with an eight-element phased-array coil. Image quality and diagnostic findings were subjectively analyzed by two radiologists and one vascular surgeon. Each distal calf and foot was divided into six arterial segments for DSA and t3D MRA, and four segments were investigated by US scan. Patency or occlusion was studied with all the techniques, whereby DSA and t3D MRA were additionally evaluated in patients having greater or less than 50% stenosis. Finally, images were visually assessed by the three observers by applying a six-point grading scale. The acquired data was statistically analyzed using McNemar's test and Wilcoxon's matched-pairs signed-rank sum test. The P values of less than an alpha level of .05 were considered to be statistically significant., Results: We achieved MRA images of diagnostic quality in all patients. Significantly more patent pedal arteries were identified by applying t3D MRA than DSA (P < .001) and US scan (P < .02). For estimating the degree of stenosis, no technique proved to be superior (P > .28). Overall image quality was rated best for t3D MRA. Additionally, potential bypass target vessels could be clearly discriminated from pedal veins due to the temporal resolution., Conclusion: In our prospective study, t3D MRA has been proven to be superior to DSA and US scan in pedal vasculature imaging in critical limb ischemia. This is a valuable, noninvasive method for detecting potential pedal bypass target arteries.

Objective: We assessed the surgical and neurological outcome of patients undergoing simultaneous repair of aortic arch and descending thoracic aortic aneurysms (DTAA) or thoracoabdominal aortic aneurysms (TAAA) via left thoracotomy or thoracolaparotomy., Methods: During a 6-year period, we performed 32 procedures in 23 male and 9 female patients with DTAA or TAAA with concomitant aortic arch aneurysms. The mean age of the patients was 50.9 years (range, 18-75 years). Twenty-two patients suffered from DTAA, 4 had type-I TAAA, and 6 had type-II TAAA. The entire aortic arch was involved in 12 patients and the distal hemi-arch in 20 patients. The mean diameter of the aneurysms was 6 cm (range, 4.9-7.6 cm). All patients were operated on according to the protocol with cerebrospinal fluid drainage, distal aortic and selective organ perfusion, as well as antegrade brain perfusion. Neuromonitoring was performed by means of motor evoked potentials (MEPs), transcranial Doppler (TCD), and electroencephalography (EEG)., Results: All patients survived the surgical procedure and 30-day mortality did not occur. At the end of the procedure, all patients had adequate MEPs, TCD, and EEG. One patient died 47 days after operation due to gastrointestinal bleeding and therapy-resistant coagulopathy. Major postoperative complications like paraplegia or paraparesis, renal failure, and myocardial infarction were not encountered. One patient had a stroke but neurological deficits were irrelevant. Mean preoperative creatinine level was 125 mmol/L, which peaked to a mean maximal level of 130 and returned to 92 mmol/L at discharge. Other complications included bleeding requiring surgical intervention (n = 4), arrhythmia (n = 1), pneumonia (n = 5), and respiratory distress syndrome (n = 2). At a median follow-up of 38 months, all but 1 patient was alive and free of re-intervention., Conclusion: Single-stage repair of aortic arch and concomitant thoracic and thoracoabdominal aortic aneurysms via left-sided thoracotomy or thoraco-laparotomy yields excellent short- and midterm outcomes. Monitoring of cerebral and spinal cord function contributes to improved neurologic outcome.

Objective: The number of thoracic aortic endovascular procedures is increasing rapidly, and the clinical outcome largely depends on the underlying aortic pathology. When primary stent grafting is unsuccessful, secondary endovascular solutions are most often feasible. However, in recurrent endovascular failure without further minimally invasive options, conservative treatments or conversion to open surgery are the only remaining therapeutic strategies., Methods: In our experience, 106 patients received thoracic aortic endovascular treatment. Five of these patients and three from other centers underwent conversion to open repair because of 4 type Ia endoleaks (3 thoracic aortic aneurysms, 1 traumatic rupture), 2 retrograde type A dissections, 1 type Ib endoleak with contained rupture, and 1 secondary false aneurysm rupture due to stent graft migration. The latter four were surgical emergencies; the other four were urgent or elective procedures. Three patients underwent supracoronary arch replacement through sternotomy. One patient had arch and proximal descending aortic replacement, three had hemiarch and descending aortic replacement, and one had descending aortic replacement through left thoracotomy. Five stent grafts were totally removed, and three endografts were left in situ. All conversions were performed according to a protocol including total extracorporeal circulation (n = 7) or left heart bypass (n = 1), cerebrospinal fluid drainage and monitoring motor-evoked potentials, transcranial Doppler, and electroencephalography., Results: All patients survived the surgical procedure. Six patients had an uneventful postoperative course, whereas necrotic cholecystitis developed in one patient who required cholecystectomy and prolonged intensive care stay. One polytrauma patient died from secondary rupture due to prosthesis infection 24 days after stent graft explantation. No stroke, paraplegia, renal failure, or other major complication occurred. With a mean follow-up of 14 months (range, 4-71 months), seven patients are alive without any sign of recurrent aortic problems., Conclusion: Failure of thoracic endovascular aortic repair comprises a new aortic pathology. Secondary endovascular treatment is feasible in most patients; however, some patients will require open surgery to repair failures of thoracic endovascular aortic treatment. These procedures constitute a large surgical trauma and require an extensive protocol, including extracorporeal circulation, neuromonitoring, and adjunctive modalities to provide organ protection. We recommend that these procedures be performed in centers with experience and the infrastructure to offer these protective measures.

Severe burn induces destabilization of the immune system and the likelihood of multiple organ dysfunction syndrome. Current studies focus on RNA-expression analyses of immune system cells, however, the present methods of analysis are complex, potentially altered by artefacts and therefore not feasible for routine analyses. The new PAXgene Blood RNA System provides "snapshot" analysis of RNA by immediate cell lysis and prevention of RNA-degradation. Using this system the aim of this study was to analyse intracellular cytokine RNA-expression under clinical conditions. Whole blood samples (PAXgene tubes) of nine severely burned patients were drawn at admission and 6, 12, 24, 48 and 72h after trauma during routine treatment. Four healthy individuals served as control. Analysis of RNA-expression of TNF-alpha as pro-inflammatory and IL-10 as anti-inflammatory mediator was performed by RT-PCR. The RNA-expression of TNF-alpha was increased at 72h after burn. The increase occurred mainly in surviving patients. In contrast, RNA-expression of IL-10 was elevated already at 24h and the difference between surviving and deceased patients occurred earlier. We demonstrate for the first time a "snapshot" analysis of cytokine RNA-expression in severely burned patients under routine conditions. The results correspond well to current hypothesis of posttraumatic MODS development.

Objective: We assessed the surgical outcome of descending thoracic aortic aneurysm repair (DTAA) and thoracoabdominal aortic aneurym (TAAA) repair in patients with Marfan syndrome., Methods: During a six year period, 206 patients underwent DTAA and TAAA repair. In 22 patients, Marfan syndrome was confirmed. The median age was 40 years with a range between 18 and 57 years. The extend of the aneurysms included 6 DTAA (1 with total arch, 2 with distal hemi-arch), 11 type II TAAA (2 with total arch, 3 with distal hemi-arch), 4 type III and one type IV TAAA. All patients suffered from previous type A (n=6) or type B (n=16) aortic dissection and 15 already underwent aortic procedures like Bentall (n=7) and ascending aortic replacement (n=8). All patients were operated on according to the standard protocol with cerebrospinal fluid drainage, distal aortic and selective organ perfusion and monitoring motor evoked potentials. In patients undergoing simultaneous arch replacement (via left thoracotomy), transcranial Doppler and EEG assessed cerebral physiology during antegrade brain perfusion. In four patients circulatory arrest under moderate hypothermia was required., Results: In-hospital mortality did not occur. Major postoperative complications like paraplegia, renal failure, stroke and myocardial infarction were not encountered. Mean pre-operative creatinine level was 125mmol/L, which peaked to a mean maximal level of 130 and returned to 92mmol/L at discharge. Median intubation time was 1.5 days (range 0.33-30 days). Other complications included bleeding requiring surgical intervention (n=1), arrhythmia (n=2), pneumonia (n=2) and respiratory distress syndrome (n=1). At a median follow-up of 38 months all patients were alive. Using CT surveillance, new or false aneurysms were not detected, except in one patient who developed a visceral patch aneurysm six years after open type II repair., Conclusion: Surgical repair of descending and thoracoabdominal aortic aneurysms provides excellent short- and mid-term results in patients with Marfan syndrome. In this series, a surgical protocol with cerebrospinal fluid drainage, distal aortic and selective organ perfusion and monitoring motor evoked potentials resulted in low morbidity and absent mortality. These outcomes of open surgery should be considered when discussing endovascular aneurysm repair in Marfan patients.

Introduction: A fundamental prerequisite for using degradable synthetic biopolymers as composite skin substitutes is the ability to establish vascular tissue. PEGT/PBT block-copolymer matrices have previously been shown as a favorable dermal substitute. In this study, quantitative data on neovascularization of PEGT/PBT block-copolymer matrices are presented., Materials and Methods: PEGT/PBT-block-copolymer discs of three different pore diameters (1: < 75 microm, 2: 75-212 microm, 3: 250-300 microm) were implanted into dorsal skinfold chambers of balb/c mice. Histological sections were evaluated 7, 14, and 21 days post implantation by light and scanning electron microscopy. Blood vessel analysis was performed by means of digital image analysis (n = 288) of hematoxylin/eosin stained sections within apical (AOF) and basal (BOF) observation fields of the matrices., Results: Twenty-one days after implantation the density of blood vessels within the BOF of the scaffolds with a pore size of 75-212 and 250-300 microm were 4.6 +/- 0.45 and 5.8 +/- 0.62 (mean +/- S.E.M.; blood vessel profiles (BVF)), respectively. In <75 microm scaffolds, smaller numbers of BVF were found (4.2 +/- 0.39). In contrast, the evaluation within the AOF revealed significantly higher numbers of BVF in 75-212 microm group (3.5 +/- 0.49) and 250-300 microm group (4.5 +/- 0.66) as compared to the < 75 microm group (2.3 +/- 0.48)., Conclusion: There is evidence that the three-dimensional structure of PEGT/PBT-block-copolymer (pore size structure) influences neovascularization. The porous structures of copolymer matrices with adequate interconnection of pores (pore sizes of 75-212 and 250-300 microm) are characterized by faster ingrowth of vascular tissue.

The use of open-source software (OSS), in which developers release the source code to applications they have developed, is popular in the software industry. This is done to allow others to modify and improve software (which may or may not be shared back to the community) and to allow others to learn from the software. Radiology was an early participant in this model, supporting OSS that implemented the ACR-National Electrical Manufacturers Association (now Digital Imaging and Communications in Medicine) standard for medical image communications. In radiology and in other fields, OSS has promoted innovation and the adoption of standards. Popular OSS is of high quality because access to source code allows many people to identify and resolve errors. Open-source software is analogous to the peer-review scientific process: one must be able to see and reproduce results to understand and promote what is shared. The authors emphasize that support for OSS need not threaten vendors; most vendors embrace and benefit from standards. Open-source development does not replace vendors but more clearly defines their roles, typically focusing on areas in which proprietary differentiators benefit customers and on professional services such as implementation planning and service. Continued support for OSS is essential for the success of our field.

Background: The breakdown of skin microcirculation is assumed to play a key role in the pathophysiology after burn injury. The aim of the present study was to develop a burn model, which allows repetitive quantitative in vivo analysis of the microcirculation after a burn injury, focusing on the interaction between leukocytes and the endothelium., Materials and Methods: Experiments were carried out on male hairless mice. Deep partial thickness burns were inflicted with a no-touch-technique to the ears. Intravital fluorescent microscopy in combination with FITC-dextran as a plasma marker was used to assess microcirculatory parameters. Leukocytes were stained with rhodamine 6G. Preburn baseline data was obtained before as well as 1, 3, 7 and 14 days subsequent to the burn injury., Results: The non-perfused area decreased significantly over the observed period and perfusion was almost completely restored at day 14. The functional vessel density was characterized by reduction of perfused vessels immediately after burn and an increase after 24h. Leukocyte endothelium interaction significantly increased immediately after injury; baseline values were reached 1 day later. The extravasation of the plasma marker into the surrounding tissue increased immediately after burn, decreased at day 1 and remained at this level during the following observation time. The venular as well as the arterial blood flow increased immediately subsequent to the burn injury, decreased after 1 day and reached baseline values at day 3., Conclusion: The presented burn model allows quantitative assessment of the dynamics of microcirculatory disturbances after thermal trauma by high quality visualization of both plasma stained microvessels and leukocyte-endothelium interaction.

Topical 5-aminolevulinic acid is used for the fluorescence-based diagnosis and photodynamic treatment of superficial precancerous and cancerous lesions of the skin. Thus, we investigated the kinetics of 5-aminolevulinic acid-induced fluorescence and the mechanisms responsible for the selective formation of porphyrins in tumors in vivo. Using amelanotic melanomas (A-Mel-3) grown in dorsal skinfold chambers of Syrian golden hamsters fluorescence kinetics were measured up to 24 h after topical application of 5-aminolevulinic acid (1%, 3%, or 10%) for 1 h, 4 h, or 8 h by intravital microscopy (n = 54). Maximal fluorescence intensity in tumors after 1 h application (3% 5-aminolevulinic acid) occurred 150 min and after 4 h application (3% 5-aminolevulinic acid) directly thereafter. Increasing either concentration of 5-aminolevulinic acid or application time did not yield a higher fluorescence intensity. The selectivity of the fluorescence in tumors decreased with increasing application time. Fluorescence spectra indicated the formation of protoporphyrin IX (3% 5-aminolevulinic acid, 4 h; n = 3). The simultaneous application of 5-aminolevulinic acid (3%, 4 h) and glycine (20 microM or 200 microM; n = 10) reduced fluorescence in tumor and surrounding host tissue significantly. In contrast, neither decreasing iron concentration by desferrioxamine (1% and 3%; n = 10) nor inducing tetrapyrrole accumulation using 1, 10-phenanthroline (7.5 mM; n = 5) increased fluorescence in tumors. The saturation and faster increase of fluorescence in the tumor together with a reduction of fluorescence by the application of glycine suggests an active and higher intracellular uptake of 5-aminolevulinic acid in tumor as compared with the surrounding tissue. Shorter application (1 h) yields a better contrast between tumor and surrounding tissue for fluorescence diagnosis. The additional topical application of modifiers of the heme biosynthesis, desferrioxamine or 1,10-phenanthroline, however, is unlikely to enhance the efficacy of topical 5-aminolevulinic acid-photodynamic therapy at least in our model.