Minor structural modifications of bisphenol A strongly affect physiological responses of HepG2 cells.

Bisphenols represent a large group of structurally similar compounds. In contrast to bisphenol A (BPA) and bisphenol S (BPS), however, toxicological data are usually scarce, thus making bisphenols an ideal candidate for read-across assessments. BPA, bisphenol C (BPC) and a newly synthesized bisphenol A/C (BPA/C) differ only by one methyl group attached to the phenolic ring. Their EC50 values for cytotoxicity and logPOW values are comparable. However, the estrogenic activities of these bisphenols are not comparable and among this group only BPC leads to a decrease of the mitochondrial membrane potential and ATP concentration in HepG2 cells. Conversely, the cell division rate was decreased by BPS, BPA, BPC and BPA/C at 10% toxicity (EC10). At lower concentrations, only BPC significantly affected proliferation. The pro-inflammatory cytokines TGFB1 and TNF were significantly upregulated by BPC only, while SPP1 was upregulated by BPA, BPA/C and BPS. BPC led to the release of cytochrome c from mitochondria, indicating that this compound is capable of inducing apoptosis. In conclusion, the read-across approach revealed non-applicable in the case of the various structurally and physicochemically comparable bisphenols tested in this study, as the presence of one or two additional methyl group(s) attached at the phenol ring profoundly affected cellular physiology.

A novel non-synonymous mutation in the melanocortin-4 receptor gene (MC4R) in a 2-year-old Austrian girl with extreme obesity.

BACKGROUND: Functionally relevant mutations in the melanocortin-4 receptor gene ( MC4R) currently display the most common major gene/allele effect on extreme obesity. OBJECTIVE: Mutation screen of the MC4R in consecutively ascertained Austrian children and adolescents with severe obesity, to analyse the phenotype of mutation carriers and to functionally characterise novel mutations. SUBJECTS AND METHODS: 102 unrelated extremely obese children and adolescents (mean BMI 33.5+/-7.1 kg/m(2), >97th centile; mean age 13.8+/-4.1 yr) and 109 parents (79 mothers/30 fathers) of 88 of these patients were studied. The MC4R coding region was screened using denaturing high-performance liquid chromatography (dHPLC); PCR products of aberrant dHPLC pattern were re-sequenced. Signal transduction properties of mutant MC4R was investigated by challenge with the highly potent agonist NDP-alpha-MSH. Cell surface expression was determined by ELISA. Magnetic resonance imaging (MRI) of the central nervous system (CNS) was applied to a 2.3 year old index patient. Body fat and bone mineral content were assessed in three of the five mutation carriers by dual energy x-ray absorptiometry (DEXA). Oral glucose tolerance test (OGTT) was applied to some mutation carriers. RESULTS: Heterozygous carriers of two non-synonymous mutations, two polymorphisms and a silent variation were identified within the study group. (1) A novel MC4R non-synonymous mutation (S136F) was detected in a 2.3 year old girl with extreme obesity (BMI 33.2 kg/m(2), >99th centile); (2) a previously described non-synonymous mutation (V253I) was identified in an obese mother (BMI 28.1 kg/m(2)) who did not transmit this mutation to her extremely obese son; (3) two known polymorphisms (V103I and I251L) were also identified; and (4) one obese mother was carrier of a silent variation (c.594C>T; I198). Co-segregation of S136F with the obesity phenotype was shown for three generations. IN VITRO functional studies revealed a complete loss of signal transduction activity of the mutant receptor while cell surface expression was only slightly reduced compared to the wild-type receptor. CONCLUSIONS: We detected a novel non-synonymous mutation (S136F) that leads to a complete loss of MC4R function IN VITRO.

Quality of life in patients undergoing orthognathic surgery - A two-centered Swedish study.

AIM: Surgical corrections of dentofacial deformities have both physical and psychological impact on quality of life (QoL). The objectives of the present study were to evaluate the impact of oral health related problems on QoL before and after a combination of orthodontic treatment and orthognathic surgery. Additionally, the study aimed to identify correlations between different dentofacial patterns and possible improvements due to treatment. MATERIAL AND METHODS: In a prospective study, we evaluated fifty patients before start of treatment, 6 weeks and 6 months postoperatively. The questionnaires used were: OHIP-14 (Short Form Oral Health Impact Profile), a condition-specific QOL approach (Orthognathic Quality of Life Questionnaires; OQLQ) and a social-demographic questionnaire. RESULTS: There was a statistically significant improvement in the OHIP domains from baseline to 6 months follow-up and for the OQLQ, the improvement was significant both at 6 weeks and 6 months in relation to the baseline data. CONCLUSION: Significant improvement of quality of life over time is proved by both OHIP-14 and OQLQ in the present study. Socio-demographic and holistic considerations are important when evaluating treatment outcome after combined orthodontic and orthognatic surgery. However, longer follow-up would be beneficial.

Fire disaster in Gothenburg 1998--surgical treatment of burns.

A tragic in-door fire disaster took place on 29 October 1998 at a discotheque in Gothenburg, Sweden. Nearly 400 youths attending a Halloween party were inside the building when the fire started, killing 61 people and injuring another 213 persons. A total of 154 youths were admitted to hospital care. Twenty-three patients requiring primary reconstructive burn surgery were followed and their records from the different burn units were examined. Total body surface area (TBSA), burn depth, surgical treatment, hospital stay, and complications were studied. In contrast to what is normally encountered in burn patients, well circumscribed predominantly full-thickness burns covering 1-40% TBSA were observed while partial-thickness burns only comprised 1-7% TBSA. Exposed bone was seen in 10 out of 23 patients. Escharotomies were performed in 11 patients, in six of whom that fasciotomies had to be performed. Primary excisions and skin grafting were performed in 22 patients. Five patients acquired amputations. Eight patients required local flaps and two had free flap coverage. Thoracic surgery was performed in one patient due to endocarditis. Severe infections occurred in eight patients. Hospital stay varied between 21 and 164 days.

Increased dermal perfusion after skin burn injury by D-myo-inositol-1,2,6-trisphosphate.

Full-thickness burn injury results in a continuous deterioration of blood flow due to vascular sludging, thrombosis formation and oedema leading to irreversible ischaemia and tissue necrosis. D-myo-inositol-1,2,6-trisphosphate (IP3) has previously been shown to reduce burn-induced oedema formation and inflammation involved in the pathophysiology of progressive ischaemia. A full-thickness burn injury (1 cm2) was induced in the abdominal skin of anaesthetized rats using an electrically heated thermoprobe. Blood flow in the experimental area was measured by laser Doppler flowmetry during 6.5 h postburn. The experiments included five groups. Three burned groups were treated intravenously with IP3 and received respectively: a bolus dose of 4 mg/kg followed by a continuous intravenous infusion of 20 mg/kg/h, 8 mg/kg + 40 mg/kg/h or 16 mg/kg + 60 mg/kg/h. One burned and one unburned control group received a corresponding bolus dose and infusion of saline. Results showed a significant inhibition of dermal ischaemia in the burned groups receiving IP3 at all dose intervals as compared to saline-treated burned rats (all P < 0.001). We conclude that IP3 improved local dermal perfusion in burned skin. Probable mechanisms of action could be the vasodilatory and anti-inflammatory properties of the agent.

Topical local anaesthetics (EMLA) inhibit burn-induced plasma extravasation as measured by digital image colour analysis.

Amide local anaesthetics have previously been shown to reduce oedema and improve dermal perfusion following experimental burns. Previous studies have used invasive techniques for burn oedema quantification which do not allow continuous monitoring in the same animal. The present study used digital image colour analysis to investigate the effect of topical local anaesthetics on burn-induced extravasation of Evans blue albumin. A standardised full-thickness burn injury (1 x 1 cm) was induced in the abdominal skin of anaesthetised rats. The burn area was subsequently covered with 0.5 g of lidocaine-prilocaine cream 5% (25 mg of each in 1 g; EMLA, ASTRA, Sweden) or placebo cream during the first hour post-burn. One hour after the burn trauma, animals received Evans blue dye intravenously. Skin colour appearances were recorded by macrophotography before the burn and 5, 60. 65, 90, 120, 150, and 180 min post-burn. Colour slides were digitised and colour changes were analysed using the normalised red-green-blue (n-rgb) colour system. Results showed a significant inhibition of Evans blue extravasation between 60 and 180 min post-burn in EMLA-treated animals versus controls. Topical local anaesthetics are potent inhibitors of burn-induced plasma albumin extravasation, probably by direct action on vascular permeability and by inhibition of various steps of the pathophysiological response after burn injury.

Intravenous lidocaine infusion in the treatment of experimental human skin burns - digital colour image analysis of erythema development.

Previous studies have shown that local anaesthetics possess a wide range of effects on the pathophysiology of burns, including inhibition of burn oedema and inhibition of progressive burn ischemia. The present randomised double-blind cross-over study in six volunteers investigated the effects of intravenous lidocaine infusion on partial thickness skin burns. A thermoprobe was used to induce a standardised thermal injury (1 cm(2)) on the flexor side of one forearm and was repeated on the opposite side 1 week later. Subjects received either an intravenous bolus dose of lidocaine (1 mg kg(-1)) immediately after the thermal trauma followed by continuous intravenous infusion of lidocaine (40 microg kg(-1) min(-1)) during 4 h or equal volumes of isotonic saline. Macrophotographs of the experimental skin area were taken preburn and 1, 2, 3, 4, and 12 h postburn and evaluated by computerised image colour analysis using normalised rgb (n-rgb) and Hue-Saturation-Intensity (HSI) colour systems as a quantitative measure of pathophysiological events. Maximum erythema occurred 2-3 h postburn. Differences between lidocaine- and placebo-treated burns were not significant during the first 4 h postburn. At 12 h postburn, the lidocaine-treated burn demonstrated a significantly faster restitution of residual erythema compared to control sites. The present study shows that intravenous lidocaine significantly inhibits the long-term inflammation-induced tissue responses to thermal trauma.

Topical D-myo-inositol-1,2,6-trisphosphate and hexylbetaine treatment reduces albumin extravasation in experimental rat skin burn injury.

The anti-inflammatory agent D-myo-inositol-1,2,6-trisphosphate (1,2,6-IP3) has shown beneficial effects in experimental burns following systemic administration. The purpose of this study was to investigate the effect of topical 1,2,6-IP3 cream on a standardised full-thickness 1 cm2 burn injury in rats. The experimental cream contained a transcutaneous absorption enhancer, hexylbetaine. Five different treatment groups were used. Two experimental groups of burned rats received either 1,2,6-IP3 cream with hexylbetaine (n = 10) or without hexylbetaine (n = 10). Two burned control groups were treated either with hexylbetaine cream (n = 10) or placebo cream (n = 10), while a third control group was untreated (n = 14). The various creams (0.5 g) were administered to the experimental burn area and allowed to remain for 3 h covered with an occlusive dressing. Spectrophotometrical quantification of Evans blue albumin extravasation was used to evaluate the effect of the experimental creams on vascular permeability following the burn trauma. Results showed a significant reduction of albumin extravasation both by 1,2,6-IP3 (p<0.05) and by hexylbetaine alone (p<0.01), as compared to placebo cream-treated animals. The transcutaneous absorption enhancer hexylbetaine did not further improve the effect of 1,2,6-IP3 on burn oedema. In conclusion, both topical 1,2,6-IP3 and hexylbetaine induced a significant reduction of albumin extravasation in burned skin. The effect of 1,2,6-IP3 could be related to previously shown anti-inflammatory actions of the agent, while the mechanisms of actions of hexylbetaine remain to be investigated.

Importance of nitric oxide in the regulation of burn oedema, proteinuria and urine output.

Burn injuries trigger a pronounced inflammatory response in the burned skin, resulting in oedema formation and impaired circulation. This response involves activation of the nitric oxide (NO) synthetic pathway, which could play a key role in the complex hemodynamic and hemostatic changes occurring as a result of a burn trauma. The results presented in full-thickness skin burns of rats show that the NO-precursor, L-arginine (n = 10), inhibit burn-induced plasma extravasation as compared to saline-treated burned controls (n = 10) (p<0.001) to a level not significantly different from nonburned animals. Administration of the NO-synthase inhibitor. NG-nitro-L-arginine (L-NNA) (n = 10), did not significantly influence burn extravasation compared to burned controls. Accumulated urine volume 90 min post-burn increased ten-fold in burned animals treated with L-arginine compared to saline-treated burned controls (p<0.001) and nonburned animals (p<0.001), while L-NNA had no significant effect on diuresis. A significantly increased proteinuria occurred in L-arginine treated burned animals as compared to burned controls and nonburned controls (p<0.001), whereas L-NNA did not significantly influence the leakage of protein in the urine. Activation of NO synthesis significantly suppresses burn edema and strongly increases diuresis along with increased proteinuria.

Role of nitric oxide in the control of burn perfusion.

Vascular changes following deep skin burns are characterised by vasoconstriction and progressive ischemia. Nitric oxide (NO) has been shown to be a potent regulator of vascular smooth muscle tone and tissue perfusion. We assessed the importance of NO on post-burn skin perfusion in rats using laser Doppler. The present results show that neither the NO-synthase inhibitor, NG-nitro-L-arginine (L-NNA) (n = 6) nor the NO precursor, L-arginine, significantly influenced skin perfusion in nonburned skin compared to saline-treated animals. In the area of full-thickness skin burn, neither L-arginine (n = 6) nor L-NNA (n = 6) had significant influence on post-burn perfusion compared to saline-treated controls (n = 6). Administration of L-NNA (n = 6) significantly impaired skin perfusion in the area adjacent to the contact burn representing a partial-thickness burn, while the NO precursor, L-arginine (n = 6) had no significant effect on burn perfusion as compared to saline-treated controls (n = 6). In conclusion, impairment of perfusion in a full thickness burn following administration of NO-synthase inhibitor suggests that nitric oxide is involved in the mechanisms responsible for maintaining adequate circulation post-burn. The lack of additional improvement of perfusion in response to L-arginine may suggest that NO synthesis in response to the thermal trauma is already at a peak.

Importance of vasoactive intestinal polypeptide in the regulation of burn perfusion.

Vasoactive intestinal polypeptide is one of the body's most potent vasodilators and has been shown to increase blood flow in a number of tissues. Its effects on postburn skin perfusion and progressive ischemia was investigated in rats exposed to partial- and full-thickness experimental skin burns. Systemic administration of VIP elicited a significant drop in mean arterial blood pressure versus saline (p<0.001) and VIP antiserum (p<0.001) both in burned and nonburned animals. VIP also decreased heart rate versus saline (p<0.05) and anti-VIP (p<0.001) in nonburned and burned animals. In contrast, VIP antiserum significantly increased blood pressure (p<0. 001) and heart rate (p<0.001) versus saline in all the groups. Skin perfusion in normal skin was significantly impaired by VIP infusions as compared to saline (p<0.01) while VIP-antiserum did not differ significantly from saline. Similarly, VIP significantly reduced blood flow versus saline-treatment in partial-thickness (p<0.01) and full-thickness burns (p<0.05) while VIP-antiserum had no significant effect on skin perfusion in any of the burned groups as compared to saline treatment. The present results show that VIP is directly involved in general cardiovascular control but plays a minor role in the maintenance of skin perfusion following a thermal injury as suggested by the lack of effect of VIP-antiserum. In contrast, exogenous administration of VIP significantly and dramatically impaired skin perfusion in normal and burned skin probably by increasing blood flow in organs of higher priority such as the brain and heart and concomitantly inducing a pronounced vasoconstriction in the skin, probably as a result of increased sympathetic effect on peripheral organs in order to maintain blood pressure.

Role of vasoactive intestinal polypeptide in burn-induced oedema formation.

Vasoactive intestinal polypeptide has been demonstrated to lack inherent effects on capillary permeability, but also to potentiate the oedema promoting actions of other inflammatory mediators or even to strongly reduce organ damage and subsequent oedema in ischemic models of the lung and heart. This study investigated the role of VIP on oedema in partial- and full-thickness skin burns of anaesthetised rats in vivo by spectrophotometrical quantification of Evans blue albumin. Results show that systemic VIP elicited a significant drop in mean arterial blood pressure versus saline (p<0. 001) and VIP antiserum (p<0.001) both in burned and non-burned animals. VIP also decreased heart rate versus saline (p<0.05) and anti-VIP (p<0.01) in non-burned and burned animals. EB-albumin in normal skin was significantly inhibited by VIP as compared to saline (p<0.05), but did not differ significantly from VIP-antiserum. A significant inhibition of EB-albumin extravasation versus saline was also seen following administration of VIP-antiserum (p<0.01). Similarly, VIP significantly reduced EB-albumin extravasation versus saline treatment in partial-thickness (p<0.01) and full-thickness burns (p<0.001), while VIP-antiserum had no significant effect on skin perfusion in any of the burned groups as compared to saline treatment. The present results show that systemic VIP is a potent inhibitor of burn oedema. This effect could be secondary to constriction of skin vessels as a result of VIP-induced systemic hypotension or be mediated by the interaction of VIP with other oedema promoting mediators released following a thermal trauma to the skin.

A new technique for the analysis of endogenous mediators released following thermal injury.

Few techniques today enable us to measure the complex processes taking place inside a burn wound in vivo. The present in vivo technique was based on a standardised burn model in rat skin. A partial- or full-thickness burn was induced and resulted in a gelatinous oedema located between the skin and the underlying rectus muscle. The oedema has distinct borders to the surrounding connective tissue and is separated and removed easily for further analysis. Myeloperoxidase (MPO) activity used as indicator of neutrofil infiltration was increased significantly in the burn oedema versus non-burned skin. Leukocyte metabolic activity was high as shown by significantly higher free radical formation (ESR) in the oedema than in surrounding burned and non-burned tissue. Leukocyte viability measured by Trypan blue stain was 70% in the oedema of full-thickness burns. In order to decide whether processes taking place in the oedema communicate freely with systemic circulation, we conducted a number of experiments. Results show in burned animals in vivo that intravenous administration of indomethacin induced a strong inhibition of PGE(2) in the burn oedema as compared with saline but, as expected, had no significant effect on LTB(4) synthesis. In conclusion, the present technique allows us to analyse the processes taking place inside the burn wound in vivo and to evaluate the effects of various agents on these processes.

Craniofacial surgery over 30 years in Göteborg.

Craniofacial surgery is a new sub-specialty in the field of plastic reconstructive surgery and is dedicated to the treatment of severe cranial and facial malformations. Craniofacial surgery gradually started in Göteborg in the late 1970's and has been acting as the Scandinavian center since 1983. Over these 30 years an almost complete change in surgical techniques has evolved. Also profound changes in timing of surgery have followed. Results have been dramatically improved based on critical evaluation of standardized registration of long-term results. One of the most dramatic developments has been the introduction of implantable stainless steel springs. This has changed the treatment of Craniosynostosis completely and has made midfacial advancement procedures possible without relapse.

Reduced albumin extravasation in experimental rat skin and muscle burn injury by D-myo-inositol-1,2,6-trisphosphate treatment.

This study investigated the effects of the anti-inflammatory agent D-myo-inositol-1,2,6-trisphosphate (IP3) on burn edema. Two sets of experiments were performed. In the first set, a full-thickness burn injury was induced in the abdominal skin of anesthetized rats. Postburn intravenous treatment was given with IP3, indomethacin or saline solution. Extravasation of Evans blue albumin in the burned tissue was quantified by a spectrophotometric technique. Results showed significant inhibition of albumin extravasation by IP3 in three of five different doses compared to saline-treated animals. In the second set of experiments, a deep full-thickness burn through the abdominal skin and rectus muscle was induced. The therapeutic window of IP3 could be more well-defined. Resulted showed a significant reduction of albumin extravasation in the skin at all four dose levels and in the abdominal muscle at three of four doses. Indomethacin had no significant effect on postburn edema formation. The mechanisms responsible for the inhibition of albumin leakage by IP3 could be secondary to reduced formation of edema-promoting inflammatory mediators by the agent, resulting in improved vascular patency.

Local anesthetics improve dermal perfusion after burn injury.

Deep partial-thickness burn injury was induced in the abdominal skin of anesthetized rats. Dermal perfusion was assessed by laser Doppler flowmetry. In the first set of experiments, one group of rats (n = 15) was topically treated with a lidocaine-prilocaine cream 5% (25 mg of each in 1 g) for 6 hours, starting 5 minutes after inducing the burn injury. In one control group (n = 14), the thermal injury was treated with placebo cream. Results showed a markedly reduced perfusion in the skin of the control animals within the first hour after burn injury, with further decrease during the following 5 hours of observation. In animals treated with the lidocaine-prilocaine cream, skin perfusion in the burned area was significantly increased during the first 30 minutes after the burn injury compared to before the burn (p < 0.01), followed by a decrease to a level below the preburn stage but significantly higher than that of control animals during the first hour after burn injury (p < 0.05). As opposed to burned control animals, skin perfusion gradually recovered toward preburn levels at the end of the experiment in local anesthetic-treated animals. In the second experimental set, four groups of animals were burned and subsequently treated with a bolus dose of lidocaine intravenously (2 mg/kg), followed by continuous intravenous lidocaine infusions at a rate of 50 (n = 10), 100 (n = 11), or 150 (n = 10) micrograms.kg-1.min-1. The infusions were started 5 minutes after the burn injury and lasted for 6 hours. Corresponding volumes of saline solution were given to burned control animals (n = 10). Results showed a significantly improved skin perfusion in the lidocaine-treated group in a dose-response fashion as compared to control animals. A maximum improvement of dermal perfusion in the burned area was induced by intravenous lidocaine at an infusion rate of 150 micrograms.kg-1.min-1 as compared to burned controls treated with isotonic saline solution infusions (p < 0.01). Results showed that topical or systemic administration of local anesthetics can prevent progressive dermal ischemia after thermal injury.

Extended free lateral arm flap with preservation of the posterior cutaneous nerve of the forearm.

The free lateral arm flap has become a well-defined and reliable flap for various reconstructive purposes. Little attention has been paid, however, to the possibility of preservation of the posterior cutaneous nerve of the forearm (nervus cutaneus antebrachii posterior) sacrifice of which results in numbness of the dorsal part of the forearm. In this study, an anatomical dissection showed that in many cases it would be possible to preserve the nerve. We did 23 free lateral arm flaps in 22 patients during the period 1989-1994. The maximum flap length was 40 cm. Standard maximum width in most cases was 6 cm, and by using a new expansion technique it reached 10 cm in one case. Furthermore, with meticulous dissection the posterior cutaneous nerve of the forearm was either preserved or cut and rejoined in 21 patients, so minimising sensory loss at the donor site.

Skin expansion. Long term follow up of complications and costs of care.

To find out our rate of complications after tissue expansion, and the cost of treatment in terms of use of hospital resources and length of sick leave, we analysed our experience of 181 expansion treatments in 97 patients undertaken between 1986 and 1991. There were 60 women and 37 men, with a mean age of 22 (range 1-74). Twenty patients had more than one period of treatment (range 2-8). The most common conditions treated were naevi (n = 75); scars (trauma--n = 33, burns--n = 17, and operations--n = 16); and breasts that required reconstruction (n = 15). Of the 181 expansions there were 29 failures (16%), and 117 complete successes (64%); fifteen of the latter developed minor complications (8%), 35 were partly successful (20%). There were 77 complications in 71 treatments (38%), and 45 expanders (25%) had to be removed prematurely because of complications. The most common complications were skin penetration (n = 15), minor infection (n = 13), and breakdown of the surgical wound (n = 13). The median (range) inpatient hospital stay was 8 days (2-39); number of visits to the outpatient clinic for filling 7 days (0-20); and total treatment time/patient 82 (19-286). We conclude that skin expansion is a useful technique, but that there is room for improvement in reducing the rate of complications and the amount of time that patients spend being treated.

Experience with the modified defatted nasolabial transposition flap in nasal reconstruction.

The nasolabial flap is the classic flap for reconstruction of nasal defects. During the last five years we have used a modified nasolabial flap in which the distal part of the flap is defatted leaving only the dermis and epidermis intact. This distal part of the flap is then folded and used as inner or outer lining which creates a reconstruction that is thinner than the original folded flap. We have used this technique in 11 patients and the results are satisfactory, with only three patients requiring minor corrections.

Reconstruction of eyelid defects: a prefabricated multilayer sandwich graft.

We have developed a new technique for reconstruction of full thickness eyelid defects. A composite three-layer skin-cartilage-mucosal unit is manufactured and tailored three-dimensionally. Use of this sandwich graft in our patients proved to be simple and safe for eyelid reconstruction and has given good results without complications in four patients.