Long-term complications of Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN): the spectrum of chronic problems in patients who survive an episode of SJS/TEN necessitates multidisciplinary follow-up.

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are severe adverse reactions to drugs that cause a life-threatening eruption of mucocutaneous blistering and epithelial sloughing. While the acute complications of SJS/TEN are well described, it is increasingly recognized that survivors may develop delayed sequelae, some of which can be associated with significant morbidity. Studies of long-term SJS/TEN outcomes mostly focus on mucocutaneous and ocular complications. However, other internal organs, such as the respiratory tract and gastrointestinal tract, can be affected. Psychological sequelae are also frequent following the trauma of widespread epidermal necrolysis. An appreciation of the 'chronic' phase of SJS/TEN is needed by clinicians caring for individuals who have survived the acute illness. This review aims to provide an update on the breadth and range of sequelae that can affect patients in the months and years following an acute episode of SJS/TEN.

Elastic properties of polycaprolactone at small strains are significantly affected by strain rate and temperature.

Tensile tests were conducted on polycaprolactone at various strain rates and temperatures. Focusing on the mechanical properties within only the small-strain elastic region, i.e. up to the inflection point in the stress-strain diagram, it was found that strain rate and temperature had significant effects on the polymer. This finding implies that the effects of strain rate and temperature on the elastic properties of polycaprolactone should be considered in the design and manufacture of rigidity-sensitive, load-bearing applications, including use as biomaterial for scaffolds in tissue engineering applications.

Retention Improvement in Fluoride Application with Cold Atmospheric Plasma.

This study aimed to apply fluoride formulations to enamel with cold atmospheric plasma (CAP) and analyze the fluoride uptake, retention, and acid resistance quantitatively. Human enamel specimens were divided randomly into 2 groups: group APF1, 1.23% acidulated phosphate fluoride (APF) gel; group APF2, 1.23% APF gel with CAP. Fluoride and CAP were applied to the samples 4 times at 1-wk intervals. The specimens were also stored in artificial saliva for 4 wk to evaluate the retention of fluoride. The fluoride content on the fluoride-treated enamel was measured by an electron probe microanalyzer. To detect the resistance to demineralization, the calcium-to-phosphate ratio of the enamel samples was measured after the application of APF gel with or without CAP, followed by soaking in the demineralization solution. In groups APF1 and APF2, the amount of fluoride detected increased depending on the application frequency, and more fluoride was detected in group APF2 than in group APF1. In the experiment examining the maintenance effect, fluoride was not detected in group APF1, whereas fluoride was detected in group APF2 up to the fourth week. As for the resistance to demineralization, the calcium-to-phosphate ratio of the enamel treated with APF and CAP was higher than that treated with APF alone, and it increased with the frequency of treatment. This study suggests that the combination treatment of CAP and fluoride improves retention of fluoride on the enamel and resistance to demineralization when compared with treatment with fluoride alone.

Eye Protection in Liver Transplantation Patients Under General Anesthesia.

BACKGROUND: Opsite (Smith & Nephew, Hull, UK) is widely used in wound care but its use in eye protection against corneal abrasion during major surgery is rarely reported. The purpose of the current study is to compare the effectiveness of using Opsite in eye protection with either wet gauze alone or with wet gauze following application of eye ointment in patients undergoing living donor liver transplantation (LDLT). METHODS: This is a prospective, double-blinded, randomized controlled trial. Forty-one patients undergoing liver transplantation were enrolled. One eye of each patient was protected with sterile gauze soaked with normal saline solution and covered with Opsite. Duratears (ALCON, Fort Worth, Tex, United States) ointment was applied to the other eye before covering it with sterile wet gauze and Opsite (ointment group). The corneal examination was carried out after fluorescein staining before and at the end of surgery by the same doctor. A Student t-test and a χ2 test were used for the statistical analyses. RESULTS: Forty-one patients with 82 eyes were observed in this study. No corneal epithelial defects were found in either the normal saline group or the ointment group. CONCLUSION: Opsite combined with wet gauze with or without additional eye ointment provided 100% protection against corneal abrasion in patients undergoing LDLT.

New antibody immobilization method via functional liposome layer for specific protein assays.

A specific protein assay system based on functional liposome-modified gold electrodes has been demonstrated. To fabricate such assay system, a liposome layer was initially grown on top of a gold layer. The liposome layer contained two kinds of functional molecules: biotin molecules for the binding sites of streptavidin and N-(10,12-pentacosadiynoic)-acetylferrocene molecules for the facile redox probe in electrochemical detections. Then, streptavidin was attached on the functional liposme-modified layer using the interaction of streptavidin-sbiotin complex. On the streptavidin-attached surface, antibody molecules, anti-human serum albumin antibodies could be immobilized without any secondary antibodies. AFM imaging of the streptavidin-attached liposome surface revealed a uniform distribution of closely packed streptavidin molecules. In situ quartz-crystal microbalance and electrochemical measurements demonstrated that the wanted antibody-antigen reactions should occur with high specificity and selectivity. Our specific antibody assay system, based on a functional liposome modified electrode, can be developed further to yield sophisticated structures for numerous protein chips and immunoassay sensors.

PPARγ Maintains Homeostasis through Autophagy Regulation in Dental Pulp.

This study investigated the relevance between pulp vitality and autophagy in aged human dental pulp cells (HDPCs) and whether peroxisome proliferator-activated receptor gamma (PPARγ) affects autophagy regulation for homeostasis in the aging progress. In vivo experiments were used in human and Sprague-Dawley rat teeth obtained from young and adult individuals. Aging- and autophagy-related molecules were determined by immunohistochemistry and hematoxylin and eosin staining. HDPCs were serially subcultured until spontaneously arrested for in vitro aging, and the replication deficiency adenovirus was introduced for PPARγ overexpression. Subsequently, the effect of PPARγ on regulation of autophagy molecules, mitochondria activity, and cell viability was assessed using Western blotting, confocal microscopy, and the MTT assay, respectively. In adult pulp tissue, autophagy molecules (autophagy protein 5, microtubule-associated protein 1A/1B light chain, and Beclin-1) were increased, but aging-related (PPARγ and heme oxygenase 1 [HO-1]) and dentinogenesis (dentin sialophosphoprotein and dentin matrix acidic phosphoprotein) molecules were decreased. In aged HDPCs, autophagy and intercellular adhesion molecule 1 and vascular cell adhesion molecule 1 were increased, while PPARγ and HO-1 were decreased. Under stimulation with lipopolysaccharide, autophagy- and aging-related molecules were differentially expressed between young and aged cells. PPARγ induced HO-1 and autophagy molecules but reduced inflammatory molecules in aged cells. In addition, PPARγ activated strong mitochondrial activity and cell viability in aging cells. Inhibition of HO-1 by tin protoporphyrin IX exacerbated autophagy and mitochondrial activity as well as cell viability in young cells. This study indicates that PPARγ maintains pulp homeostasis through the regulation of autophagy molecules during the life span of HDPCs.

Posterior capsule opacification in eyes with a silicone or poly(methyl methacrylate) intraocular lens.

PURPOSE: To evaluate the effect of poly(methyl methacrylate) (PMMA) and silicone intraocular lenses (IOLs) on posterior capsule opacification (PCO) after cataract surgery. SETTING: Kangnam St. Mary's Hospital, Seoul, Korea. METHODS: This retrospective study comprised 48 patients (54 eyes) who had neodymium:YAG (Nd:YAG) laser posterior capsulotomy from March 1995 to December 1997. All operations were performed by 1 surgeon using the same technique except for incision method. RESULTS: Mean interval from cataract surgery to Nd:YAG capsulotomy was 31 months in the PMMA group and 15 months in the silicone group. The difference between groups was statistically significant (P = .0002). The ratio of Elschnig pearl to fibrosis type PCO was 16:6 in the PMMA group and 14:18 in the silicone group. Mean total Nd:YAG laser energy used was 256 mJ in the PMMA group and 309 mJ in silicone group. However, the damage caused by the laser was more severe and more common in the silicone group. CONCLUSION: Silicone IOLs induced PCO faster than PMMA IOLs, with fibrosis the most common type in the silicone group. Precautions should be taken to prevent damage during Nd:YAG laser capsulotomy in eyes with a silicone IOL.

The use of pterygomaxillary implants in the partially edentulous patient: a preliminary report.

One hundred eighty-seven implants were placed in the maxillary posterior areas of 44 partially edentulous patients (29 female; 15 male). The mean age was 62 years (range 36 to 82 years). Fifty-one of the 187 implants were placed in the pterygomaxillary area and further restored with fixed prostheses. The mean number of implants per prosthesis was 3.7 (range 1 to 6) for the maxillary posterior area. These 51 implants are the subject of this report. During stage II surgery and before loading, six implants were not osseointegrated and were removed. After a mean loading period of 12.6 months (range 1 to 63 months), one additional implant was lost. Seven of 51 implants were removed (13.7%). Failure rates according to implant size and bone quality were also analyzed. The average loss of marginal bone height was 1.3 mm on the mesial and 1.1 mm on the distal surfaces between 1 and 3 years of loading. This study demonstrates the possible and successful use of the pterygomaxillary site for implant placement.

Kuwanon G: an antibacterial agent from the root bark of Morus alba against oral pathogens.

Kuwanon G was isolated from the ethyl acetate fraction of methanol extract of Morus alba and its structure was elucidated by 13C-NMR, 1H-NMR and FAB-MS. Antibacterial activity of kuwanon G was investigated by the minimum inhibitory concentration (MIC) test and the viable cell count method. MIC of kuwanon G against Streptococcus mutans causing dental caries was determined to be 8.0 microg/ml. The bactericidal test showed that kuwanon G completely inactivated S. mutans at the concentration 20 microg/ml in 1 min. Kuwanon G also significantly inhibited the growth of other cariogenic bacteria such as Streptococcus sobrinus and Streptococcus sanguis, and Porpyromonas gingivalis causing periodontitis. Transmission electron microscopy (TEM) of kuwanon G treated cells demonstrated remarkable morphological damage of the cell wall and condensation of the cytoplasm.

Mandibular anatomy related to sagittal split ramus osteotomy in Koreans.

Sagittal split ramus osteotomy (SSRO) is one of the surgical techniques used to correct mandibular deformities. In order to prevent many surgical anatomical problems, we observed the anatomical structures related to SSRO. In dry mandibles of Koreans, lingular tips were located somewhat posteriorly and superiorly on the mandibular ramus. On the coronal sections of mandible, the mean cortical width of facial cortex was increased toward the ramus region while the lingual cortex was thinnest in the ramus region. On the same sections, all the fusion points of the buccal and lingual cortical plate were located above the mandibular lingula and beneath the mandibular notch. So, performing the SSRO on Koreans, medial horizontal osteotomy should be done through the superior aspect of the mandibular lingula. The cut line is extended 5-8 mm posterior to the mandibular lingula to preserve sufficient cortical width to strengthen the involved osseous segments and reduce possible surgical complications.

Beak trimming effects on behavior patterns, fearfulness, feathering, and mortality among three stocks of White Leghorn pullets in cages or floor pens.

White Leghorn pullets of the Y1, Y2, and North Central Randombred (NCR) experimental stocks were used. Half of the birds of each stock had half of the upper and less of the lower mandible removed at 4 wk of age by making a V-shaped cut as viewed from the side (BT), whereas the other half retained their beaks intact (IN). Pullets were moved from growing pens to a layer house at 18 wk of age. Seventy-two cages and 30 floor pens were filled with 6 and 20 birds per unit, respectively. Pullets within a cage or floor pen were all of the same genetic stock and beak treatment. All measurements were performed within 10 wk after housing, except for mortality in cages. When kept in cages, genetic stocks did not show behavioral differences. However, in floor pens, stock differences were detected in feeding, crouching, and nonaggressive pecking. When kept in cages, the stocks also differed in 24-wk body weight, weight gain from 18 to 24 wk, and certain measures of fearfulness in both cages and pens, and in feather condition at 21 and 22 wk. Mortality from cannibalism and hen-days survival of caged IN pullets differed among genetic stocks. Mortality from cannibalism was absent among pullets kept in experimental floor pens. In cages, BT pullets were less active, gained less weight, and had lower incidence of cannibalism than IN pullets. Also, BT pullets were less nervous and had better feather condition than IN pullets. However, trimming beaks to prevent cannibalism was less effective in NCR pullets than in Y1 or Y2 pullets. In floor pens, BT pullets showed less activity and reduced feeding frequency and less fearfulness as indicated by duration of induced tonic immobility. Agonistic behaviors were not different between BT and IN pullets. From these results, beak trimming could be interpreted as having either stressful or stress-alleviating effects, depending on the criteria used. However, proper beak trimming appears beneficial when cannibalistic pecking is likely to be a problem. The relative benefits of beak trimming vary among genetic stocks.

Vacuum delivery at The Maternity Hospital Kuala Lumpur: a comparison of metal and silicone cups.

OBJECTIVE: To compare the advantages and disadvantages of the New Bird metal cups and silicone cups in terms of maternal and foetal outcome. To study the adverse effects and factors associated with failed vacuum deliveries. DESIGN: A prospective randomised study of all vacuum deliveries from 1 December 1991 to 31 April 1992. The Hanshin electrical vacuum pump was used. SETTING: A large obstetric unit-The Maternity Hospital Kuala Lumpur (MHKL). SUBJECTS: Seventy-two consecutive patients where vacuum deliveries were indicated. Forty had metal and 32 had silicone cups. Another 7 vacuum deliveries using the manual vacuum pump were excluded. MAIN OUTCOME MEASURES: Success rate of vaginal delivery, birth canal injuries, post-partum haemorrhage, duration of hospital stay, Apgar score, foetal injuries (scalp-ecchymosis, haematomas) neonatal jaundice, the rate of special care nursery (SCN) admission and neonatal mortality rate. RESULTS: Failure to deliver with silicone cups alone was 21.9% compared to 10% for metal cups alone. Material morbidities and serious foetal scalp injuries were almost the same in both cups. However, minor foetal scalp injuries were significantly lower with silicone cups. Maternal height and baby's weight had no independent predictive values for successful vacuum delivery. When the foetal head was palpable per abdomen, the failure rate was 54.5% compared to 8.2% when it was not. Failed vacuum deliveries were associated with increased maternal and foetal morbidities. CONCLUSION: Silicone cups and metal cups can be equally dangerous to the baby. Although our sample size was small, we recommend that vacuum delivery be avoided if the foetal head is palpable per abdomen.

Advanced biomatrix designs for regenerative therapy of periodontal tissues.

Periodontitis is an inflammatory disease that causes loss of the tooth-supporting apparatus, including periodontal ligament, cementum, and alveolar bone. A broad range of treatment options is currently available to restore the structure and function of the periodontal tissues. A regenerative approach, among others, is now considered the most promising paradigm for this purpose, harnessing the unique properties of stem cells. How to make full use of the body's innate regenerative capacity is thus a key issue. While stem cells and bioactive factors are essential components in the regenerative processes, matrices play pivotal roles in recapitulating stem cell functions and potentiating therapeutic actions of bioactive molecules. Moreover, the positions of appropriate bioactive matrices relative to the injury site may stimulate the innate regenerative stem cell populations, removing the need to deliver cells that have been manipulated outside of the body. In this topical review, we update views on advanced designs of biomatrices-including mimicking of the native extracellular matrix, providing mechanical stimulation, activating cell-driven matrices, and delivering bioactive factors in a controllable manner-which are ultimately useful for the regenerative therapy of periodontal tissues.

Impaired thrombin generation in Reelin-deficient mice: a potential role of plasma Reelin in hemostasis.

BACKGROUND: Reelin is a large extracellular glycoprotein that is present in the peripheral blood. That Reelin interacts with the coagulation components and elicits a functional role in hemostasis has not yet been elucidated. OBJECTIVES: The hemostatic activity of Reelin is investigated and defined in this study. METHODS: The interplay of Reelin with coagulation components was elucidated by far-Western and liposome/platelet binding assays. In vivo and ex vivo hemostasis-related analyses of Reelin-deficient mice and plasma were also performed. RESULTS: Reelin interacted with the liposomes containing phosphatidylserine (PS) or phosphatidylcholine. Instead of interacting with known Reelin receptors (ApoE receptor 2, very low density lipoprotein receptor and integrin ß1), Reelin interacted with PS of the activated platelets. The interaction between Reelin and the coagulation factors of thrombin and FXa was also demonstrated with the Kd of 11.7 and 21.2 nm, respectively. Reelin-deficient mice displayed a prolonged bleeding time and an increase in rebleeding rate. Despite the fact that Reelin deficiency had no significant effect on the clotting time of prothrombin and activated partial thromboplastin time, the fibrin clot formation was abnormal and the fibrin clot structure was relatively loosened with reduced clot strength. Abnormal fibrinogen expression did not account for the hemostatic defects associated with Reelin deficiency. Instead, thrombin generation was impaired concomitant with an altered prothrombin cleavage pattern. CONCLUSIONS: By interacting with platelet phospholipids and the coagulation factors, thrombin and FXa, Reelin plays a selective role in coagulation activation, leading to thrombin generation and formation of a normal fibrin clot.

Finite element analysis of bone-implant biomechanics: refinement through featuring various osseointegration conditions.

A refinement technique is proposed for developing finite element models capable of simulating peri-implant bone conditions for bone types II, III, and IV at various degrees of osseointegration. The refined models feature a transition region between bone (cortical and cancellous) and implant and designate it partially to fully osseointegrated by assigning corresponding fractions of the bulk bone's elastic properties to this region. Bone is assumed to be transversely isotropic. The refined technique is implemented in a case study, in which osseointegrated (25-100%) peri-implant bone, type II, III, or IV with an implant attached, is loaded with a 100 MPa occlusal load. The biomechanics of this peri-implant bone was simulated and analysed. Results showed that the less dense bone must support higher stress and strain, especially at the cortical region. Higher degree of osseointegration induced higher stress but lower strain. Both the bone type and the osseointegration condition significantly affected the stress-strain relation. For minimum stress and strain, denser and more osseointegrated peri-implant bone is desirable. When bone failure criteria were set, based on the yield strength and strain of the bone, a higher degree of osseointegration was needed for the less dense peri-implant bone to be considered safe.

Grafting of molecularly imprinted polymers on iniferter-modified carbon nanotube.

Molecularly imprinted polymers (MIPs) were grafted on iniferter-modified carbon nanotube (CNT). Tween 20 was first immobilized on CNT by hydrophobic interactions. The hydroxyl-functionalized CNT was modified by silanisation with 3-chloropropyl trimethoxysilane. The iniferter groups were then introduced by reacting the CNT-bound chloropropyl groups with sodium N,N-diethyldithiocarbamate. UV light-initiated copolymerization of ethylene glycol dimethacrylate (crosslinking agent) and methacrylic acid (functional monomer) resulted in grafting of MIP on CNT for theophylline as a model template. MIPs grafted on CNT were characterized with elemental analysis, scanning electron microscopy, and thermogravimetric analysis. The theophylline-imprinted polymer on CNT showed higher binding capacity for theophylline than non-imprinted polymer on CNT and selectivity for theophylline over caffeine and theobromine (similar structure molecules). The data of theophylline and caffeine binding into the theophylline-imprinted polymer correlated well with the Scatchard plot. These MIPs on CNT can potentially be applied to probe materials in biosensor system based on CNT field effect transistor.

[Studies on male sterilization techniques].

PIP: After a review of the theory, incidence in Korea, indications, complications, and operative technique of vasectomy, clinical observations on 2 procedures are given. Vas reanastomosis was performed on 185 men, aged 19-58, using general anesthesia. Ejaculates of 178 of the men showed 81% contained viable sperm. more than 10 years, 58%). Later pregnancies were reported by 35% of the men. Reversible vas occlusion by insertion of intravasal thread (IVT) was performed on 544 men under local anesthesia. Sperm passage was occluded in 96% of the men. After 9 months, 42 men had the IVT removed; 83% had viable sperm 1 month later. Advantages of the IVT technique are 1) simplicity of reversibility, 2) low cost, 3) no postoperative pain or discomfort, and 4) outpatient/local anesthesia procedure. A disadvantage is the lower success rate of vas occlusion due to luminal dilation around the IVT.^ieng

Treatment of a large odontogenic keratocyst using the Brosch procedure.

The modified Brosch procedure has been described. It represents a reasonable alternative to resection or marsupialization when treating large OKC that occupy the molar, angle, and ramus regions of the mandible. Extraction of teeth affected by the lesion as well as generous removal of partially eroded bone and overlying soft tissues may contribute to lower recurrence rates. Cryosurgical or mechanical treatment of the bony cavity, which is well visualized using this technique, may also lead to improved long-term results. Treatment must be followed by continued, careful observation of the patient.

Microencapsulation of fragrant oil via in situ polymerization: effects of pH and melamine-formaldehyde molar ratio.

Microcapsules containing fragrant oil (Foral oil) were synthesized via the in situ polymerization method using melamine-formaldehyde (M-F) as a wall material. The encapsulation efficiency and other physical properties were analysed with varying formaldehyde/melamine (F/M) mole ratio and pH of emulsion medium. The pH of the reaction medium was varied from 5.0-6.0 and the F/M molar ratio, 2.3 - 5.5. Microcapsules containing fragrant oil were synthesized successfully and their particle sizes ranged from 12-15 micro m. Encapsulation efficiency of fragrant oil varied from 67-81%. It was found that both pH and F/M molar ratio have an effect on the separation of M-F prepolymer, consequently the morphology of the surface of the microcapsule was changed as well as encapsulation efficiency. The encapsulation mechanism, focusing on the liquid-liquid phase separation of methylolmelamines and formation of M-F precursor particle, was described to explain the surface morphology and encapsulation efficiency.