Elevated propionate signalling drives Pde9a overexpression and contractile dysfunction through increased histone acetylation and propionylation

Funding Acknowledgements

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): British Heart Foundation and Propionic Acidemia Foundation

Background

In the heart, various metabolic pathways produce the three-carbon intermediate, propionate. This metabolite has been postulated to increase histone propionylation and acetylation (via deacetylase inhibition), and therefore affect transcription. Normally, propionate levels are kept low by propionyl-CoA carboxylase (PCC), but build-up has been reported in cardiometabolic diseases. The highest levels are attained in propionic acidaemia (PA; mutations in PCC), which also serves as a model for studying propionate biology [1].

Purpose

To establish the effect of propionate on cardiac gene expression and physiology using a mouse model of elevated propionate/propionyl-CoA signalling.

Methods

Experiments were performed using either wild-type (WT) neonatal ventricular myocytes (NRVMs) treated with propionate in vitro, or the hypomorphic mouse model of PA (Pcca-/- A138T) [2]. IC-MS metabolomics was performed on methanol-extracted metabolites. RNA-sequencing was carried out on an Illumina HiSeq 4000. For chromatin immunoprecipitation (ChIP), chromatin was isolated from PFA-fixed ventricular tissue. cGMP levels were measured by the FRET-based sensor, cGi500. Ca2+ transients were imaged in isolated myocytes using FuraRed. Cine-MRI was performed in a 7 tesla MR scanner.

Results

PA mice had the metabolic signature of propionate accumulation in plasma and cardiac lysates (metabolomics). RNA-seq of ventricular lysates identified differentially expressed genes (DEGs), but the effect was more pronounced in females. Thus, subsequent experiments were performed in females. To determine which DEGs are likely a direct response to propionate, RNA-seq was performed on propionate-treated NRVMs. The most significant DEGs common to both datasets were upregulated Pde9a (cGMP-selective phosphodiesterase) and Mme (degrades natriuretic peptides). ChIP-qPCR for histone acylation in PA and WT hearts demonstrated increases in H3K27ac at Pde9a, and strikingly, increases in propionylation at Pde9a and Mme, indicating a mechanism for this transcriptional induction. Propionate-treated NRVMs show greater sensitivity of cGMP to pharmacological inhibition of PDE9A (measured by FRET), consistent with Pde9a induction. Such changes are expected to result in diastolic dysfunction [3]. Indeed, ventricular myocytes from PA mice had higher diastolic Ca2+. Cine-MRI confirmed contractile dysfunction in vivo, with PA mice manifesting increased end-systolic and end-diastolic volumes.

Conclusions

We demonstrate that cardiac elevations of the metabolic intermediate, propionate, increases histone modifications that drive transcriptional changes in the heart, including those involved in cyclic nucleotide signalling. We also present evidence for histone propionylation, which has not been described previously in the heart. Thus, using a mouse model of a rare metabolic disease, we show how propionate/propionyl-CoA signalling affects cardiac function through epigenetic changes.

Antioxidant defense mechanisms and its dysfunctional regulation in the mitochondrial disease, Friedreich's ataxia

Redox stress is associated with the pathogenesis of a wide variety of disease states. This can be amplified potentially through redox active iron deposits in oxidatively active organelles such as the mitochondrion. There are a number of disease states, including Friedreich's ataxia (FA) and sideroblastic anemia, where iron metabolism is dysregulated and leads to mitochondrial iron accumulation. Considering FA, which is due to the decreased expression of the mitochondrial protein, frataxin, this iron accumulation does not occur within protective storage proteins such as mitochondrial ferritin. Instead, it forms unbound biomineral aggregates composed of high spin iron(III), phosphorous and sulfur, which probably contributes to the observed redox stress. There is also a dysregulated response to the ensuing redox assault, as the master regulator of oxidative stress, nuclear factor erythroid 2-related factor-2 (Nrf2), demonstrates marked down-regulation. The dysfunctional response of Nrf2 in FA is due to multiple mechanisms including: (1) up-regulation of Keap1 that is involved in Nrf2 degradation; (2) activation of the nuclear Nrf2 export/degradation machinery via glycogen synthase kinase-3β (Gsk3β) signaling; and (3) inhibited nuclear translocation of Nrf2. More recently, increased microRNA (miRNA) 144 expression has been demonstrated to down-regulate Nrf2 in several disease states, including an animal model of FA. Other miRNAs have also demonstrated to be dysregulated upon frataxin depletion in vivo in humans and animal models of FA. Collectively, frataxin depletion results in multiple, complex responses that lead to detrimental redox effects that could contribute to the mechanisms involved in the pathogenesis of FA.

Factors affecting peri-implant fracture following locking plate for osteoporotic distal femur fractures

INTRODUCTION

The purpose of this study is to evaluate the outcomes and to analyze the risk factors for the occurrence of peri-implant fracture after treatment of osteoporotic distal femoral fractures using a locking plate.

HYPOTHESIS

Risk factors affecting peri-implant fracture exist after locking plate fixation in osteoporotic distal femur fracture.

MATERIALS AND METHODS

Eighty-nine cases (88 patients) with osteoporotic distal femoral fractures were evaluated between January 2006 and January 2014. The cohort included 13 men and 76 women with a mean age of 70.4 (50-91). Mean duration of follow-up was 47.9 months (12 to 106). All patients with distal femoral fracture were treated with a locking compression plate. Bone mineralized densitometry measurement was obtained from all patients. Risk factors including sex, age, rheumatoid arthritis (RA), taking of bisphosphonate, primary or periprosthetic fracture after total knee arthroplasty (TKA), open or closed fracture, types of the most proximal screw (locking/cortical), and number of proximal screws were analyzed. Complication, union, time to union, and range of motion of knee were also evaluated.

RESULTS

All patients had osteoporosis with the mean BMD of -3.16 (-2.5∼-5.4). The mean range of motion of knee was 126 degrees (90-145). Eighty-four cases (94.4%) showed union, the mean time to union was 14 weeks (10-42). Peri-implant fractures occurred in four patients (4.5%) after bone union at mean 37.5 months (14-62) postoperatively. Eight patients had angular deformities of over 5 degrees. Nonunion was observed in 5 cases and superficial wound infection in 2 cases. There were eight patients with RA, two of whom had suffered a peri-implant fracture. In statistical analysis, rheumatoid arthritis or periprosthetic fracture in TKA patients was a risk factor for peri-implant fracture (P=0.039, 0.019, respectively), and other factors showed no statistical differences.

CONCLUSIONS

Treatment using a locking plate showed favorable outcomes in osteoporotic distal femoral fractures. However, peri-implant fracture could occur in patients with RA or periprosthetic fracture after TKA. Therefore, cautious consideration is required for management of osteoporotic distal femur fracture in patients with RA or periprosthetic fracture after TKA. Analysis of more cases will be needed in order to achieve conclusive results.

LEVEL OF EVIDENCE

Therapeutic study, level IV (retrospective study). See the Guidelines for Authors for a complete description of levels of evidence.

Successful outcome with minimally invasive plate osteosynthesis for periprosthetic tibial fracture after total knee arthroplasty

INTRODUCTION

The incidence of periprosthetic fractures after total knee arthroplasty (TKA) is increasing, and treatment is becoming more necessary. In periprosthetic tibial fractures, the stem of the tibial component largely occupies the medullary canal of the proximal tibia, which limits the selection of implants. The purpose of this study was to evaluate the effectiveness of the minimally invasive plate osteosynthesis (MIPO) technique with locking plates for periprosthetic tibial fractures after TKA.

MATERIALS AND METHODS

Sixteen patients with periprosthetic tibial fracture after TKA were included. There were 6 type II and 10 type III fractures according to the Felix classification. Ten patients had fractures in the proximal metaphysis, and 6 in the diaphysis. MIPO using locking plates was performed on the medial side in 4 cases, the lateral side in 2 cases, and both in 10 cases. Radiographic results included time to union, alignment, and malunion. Clinical results included range of motion (ROM), functional activity data, Knee Society scores, and complications.

RESULTS

Fourteen of 16 fractures achieved union at 17.1 weeks (range, 14-24) postoperatively. There were 2 failures that required a secondary procedure. Except one for 1 case with varus malunion, all had acceptable alignment. Mean ROM at the final follow-up was 108.8° (range, 15-135°), and 15 patients recovered pre-injury knee joint activity. Mean knee and function scores were 88.9 (range, 77-100) and 83.3 (range, 60-100), respectively. Knees with fewer than 8 cortices giving purchase to screws in the proximal segment showed higher failure rates (P=0.025).

DISCUSSION

MIPO with locking plates can achieve satisfactory results for periprosthetic tibial fractures after TKA. Rigid fixation of the proximal segment may be necessary for successful outcome.

LEVEL OF EVIDENCE

IV.

Evaluating augmentation with calcium phosphate cement (chronOS Inject) for bone defects after internal fixation of proximal tibial fractures: A prospective, multicenter, observational study

INTRODUCTION

Managing subchondral bone defects in proximal tibia fractures after plateau reduction is an important consideration. ChronOS Inject is a recently developed calcium phosphate bone substitute that shows relatively fast osteointegration.

HYPOTHESIS

Using chronOS Inject during internal fixation of proximal tibial fractures provides a satisfactory treatment option that is both clinically and radiologically safe.

PATIENTS AND METHODS

Patients enrolled in this study were treated with chronOS Inject bone void filler, during internal fixation of proximal tibial fractures. Patients were evaluated preoperatively and at 6 weeks, 6 and 12 months postoperative. Radiographic union was assessed using plain films supplemented by CT scans. Pain, function and adverse events were collected at all visits. A total of 36 patients were enrolled in the study and treated according to a predetermined protocol. Seven of the 36 patients (19.4%) were lost to follow-up.

RESULTS

Successful radiographic union was achieved in 27/29 (93.1%) of patients at final follow-up. Articular subsidence of>2mm only occurred in one patient. Statistical analysis showed significant improvements both in leg pain and knee function. Progress in knee function was observed in 93.1% (27/29) of patients from 6 weeks to 12 months. No product-related complications were reported.

CONCLUSIONS

Successful union was achieved based on radiographic criteria as well as clinical outcomes. When managing bone defects after internal fixation of proximal tibial fractures, the use of chronOS Inject resulted in significant improvement of knee function and reduction of leg pain.

LEVEL OF EVIDENCE

Level IV, prospective observational study.

Seasonal isolation of microalgae from municipal wastewater for remediation and biofuel applications

AIMS

The objective of the study was to isolate the microalgae strains from treated municipal wastewater in both summer and winter seasons in order to identify strains better suited for nutrient remediation and biofuel production under either cooler or warmer temperatures.

METHODS AND RESULTS

Fifty-six strains in total were isolated and identified by DNA sequencing from effluent samples collected from a local wastewater treatment plant during the summer and winter of 2011. Screening of 41 isolates based on the fatty acid productivity at either 22 or 10°C resulted in the selection of 12 strains organized into two groups of 6-the M (mild) and C (cool) groups, respectively. Four of the C-group strains were isolated from the winter sample, while four of the M-group isolates were isolated from the summer sample. Fatty acid pools in M-group strains were heavily regulated in response to growth temperature while C-group strains were more insensitive. In three of the six C-group strains, the rates of biomass and fatty acid productivity at 10°C exceeded the corresponding rates at 22°C. Conversely, M group were always more productive at 22 compared to 10°C. Mixotrophic strategies to enhance productivity were generally unsuccessful in M-group strains at 22°C but proved to be more effective in C-group cultures at 10°C.

CONCLUSIONS

In general, C-group strains appeared better suited for growth in municipal wastewater at 10°C, while M-group strains were better suited at 22°C. On balance, C-group isolates were more likely to come from winter wastewater samples while M-group strains were more likely to come from the summer sample.

SIGNIFICANCE AND IMPACT OF THE STUDY

Our results demonstrate that the effects of temperature on microalgal growth for wastewater remediation can be mitigated somewhat by isolation and careful selection of strains adapted to seasonal wastewater conditions.

Communication disruption of guava moth (Coscinoptycha improbana) using a pheromone analog based on chain length

The guava moth, Coscinoptycha improbana, an Australian species that infests fruit crops in commercial and home orchards, was first detected in New Zealand in 1997. A four-component pheromone blend was identified but is not yet commercially available. Using single sensillum recordings from male antennae, we established that the same olfactory receptor neurons responded to two guava moth sex pheromone components, (Z)-11-octadecen-8-one and (Z)-12-nonadecen-9-one, and to a chain length analog, (Z)-13-eicosen-10-one, the sex pheromone of the related peach fruit moth, Carposina sasakii. We then field tested whether this non-specificity of the olfactory neurons might enable disruption of sexual communication by the commercially available analog, using male catch to synthetic lures in traps in single-tree, nine-tree and 2-ha plots. A disruptive pheromone analog, based on chain length, is reported for the first time. Trap catches for guava moth were disrupted by three polyethylene tubing dispensers releasing the analog in single-tree plots (86% disruption of control catches) and in a plots of nine trees (99% disruption). Where peach fruit moth pheromone dispensers were deployed at a density of 1000/ha in two 2-ha areas, pheromone traps for guava moth were completely disrupted for an extended period (up to 470 days in peri-urban gardens in Mangonui and 422 days in macadamia nut orchards in Kerikeri). In contrast, traps in untreated areas over 100 m away caught 302.8 ± 128.1 moths/trap in Mangonui and 327.5 ± 78.5 moths/ trap in Kerikeri. The longer chain length in the pheromone analog has greater longevity than the natural pheromone due to its lower volatility. Chain length analogs may warrant further investigation for mating disruption in Lepidoptera, and screening using single-sensillum recording is recommended.

Immediate induction of heat shock proteins is not protective against cryopreservation in normal human fibroblasts

Heat shock proteins (HSPs) were first identified as proteins whose synthesis was enhanced by stresses, such as increased temperature. HSPs can protect cells from various cytotoxic factors by stabilizing proteins. Thus, it could be hypothesized that heat induced HSPs can provide protective effects against cryopreservation-induced cell death. The aim of this study was to determine whether induction of HSPs can increase the cell viability of normal human fibroblasts after cryopreservation. Cytotoxic effects of heat treatment were tested and the induction of HSPs was assessed by examining time-dependent HSP expression. A cell counting method using fluorescence microscopy was used to determine the viability of cells. In addition, the effects of geranylgeranylacetone were evaluated in terms of HSP expression and cytoskeleton changes. The results of this study showed that immediate induction of HSPs does not protect normal human fibroblasts against cryopreservation-induced cell death possibly by inducing cytoskeleton changes.

Cervi cornus Colla (deer antler glue) induce epidermal differentiation in the reconstruction of skin equivalents

In the reconstruction of skin equivalents (SEs), keratinocyte differentiation is important because epidermal differentiation is closely related with barrier function. The aim of this study was to investigate the effects of Cervi cornus Colla (CCC) on the stem cell activity and epidermal differentiation in the reconstruction of skin equivalent. Four different models were constructed according to different composition of dermal substitute. Results showed similar morphologic findings when hyaluronic acid (HA) and/or CCC was added. But, immunohistochemical staining showed that p63 was significantly increased by addition of HA and/or CCC. Increased staining of integrin α6 and β1 was variably observed when HA and/or CCC was added to make dermal substitute. These finding showed that addition of HA and/or CCC may affect the stem cell activity in the reconstruction of skin. Furthermore, filaggrin expression was much increased when CCC was added. It showed that epidermal differentiation was significantly improved by addition of CCC. In conclusion, simultaneous presence of HA and CCC contributed to the stem cell activity and epidermal differentiation in the reconstruction of SE. Legislation in the EU prohibits marketing cosmetics and personal care products that contain constituents that have been examined through animal experiments. To avoid these limitations, SEs can be used for testing the safety or the efficacy of cosmetic ingredients. Therefore, our results showed that combined use of HA and CCC can be helpful for the reconstruction of SE with good stem cell activity and epidermal differentiation.

Acquired bilateral melanosis of the neck in perimenopausal women

BACKGROUND

Acquired bilateral patchy or mottled pigmentation of the neck has occasionally been observed.

OBJECTIVE

To investigate the clinical and histopathological characteristics of this pigmentation.

METHODS

Fourteen patients were included in the study. Patch and photopatch tests, and laboratory tests including serum hormonal evaluation were performed. Skin biopsies were performed on lesional skin and perilesional normal skin.

RESULTS

All the patients were women and all were perimenopausal. The lesions were characterized by bilateral, symmetrical, brown-to-grey patchy or mottled pigmentation on the lateral neck. There were positive photopatch results in some cases, but their relevance was doubtful. All laboratory findings were within the normal ranges. The histological findings showed marked accumulation of pigment in the dermis with perivascular lymphocytic infiltration. A significantly higher expression of melanogenesis-associated proteins and an increased number of melanocytes were observed in the epidermis of the lesional skin. The melanin-bearing cells in the dermis were stained with factor XIIIa or CD68, but the majority of these cells were identified as factor XIIIa+ dermal dendrocytes. Some brown pigments were mixed with light brown or golden brown pigment that was positive in iron staining.

CONCLUSIONS

These cases seem to represent a continuum of Riehl melanosis. However, the principal distribution of the pigmentation is a distinguishing feature. Any consistent predisposing factors were not established, but there may be a role for subclinical injury or inflammation as possible causative factors for development of the pigmentation.

Ultraviolet-induced red fluorescence of patients with acne reflects regional casual sebum level and acne lesion distribution: qualitative and quantitative analyses of facial fluorescence

BACKGROUND

The ultraviolet (UV)-induced red fluorescence of patients with acne has been considered to be caused by Propionibacterium acnes.

OBJECTIVES

To study the correlation of the facial red fluorescence with the casual sebum level and the number of acne lesions and to investigate the difference in clinical features, according to both distribution and proportion of fluorescence.

METHODS

A total of 878 patients clinically diagnosed with acne vulgaris were included. Inflammatory and noninflammatory acne lesions were counted separately. UV fluorescent photography and casual sebum level measurements were performed. UV-induced fluorescence patterns were classified according to the facial distribution. The proportions of UV-induced red fluorescence were calculated.

RESULTS

We identified six different fluorescence distribution patterns in the T-zone (the forehead, nose and chin) and three different patterns in the U-zone (both cheeks). The proportion of fluorescence in the U-zone showed a positive correlation with the casual sebum level and the number of acne lesions. In the T-zone, the fluorescence proportion correlated with the casual sebum level, but not with the number of acne lesions. As the patients' age and the age at onset increased, the distribution of fluorescence changed from the upper part of the T-zone to the lower part, and to the centre of the face in the U-zone.

CONCLUSIONS

Our results support the hypothesis that the origin of facial red fluorescence is sebum. In patients with acne, analyses of the pattern and proportion of UV-induced red fluorescence can be useful for evaluating the sebum secretion and selecting efficient treatment modalities.

Defective barrier function in melasma skin

BACKGROUND

Melasma is characterized by increased pigmentation and photodamaged features, which include solar elastosis. Recently, we detected the downregulation of the genes most associated with lipid metabolism using microarray analysis in melasma. These findings suggested that lesional skin may have different biophysical characteristics, and, in particular, an altered skin barrier function.

OBJECTIVE

To determine the cutaneous biophysical characteristics of melasma.

METHODS

The melanin index, erythema index, stratum corneum hydration, sebum content and transepidermal water loss (TEWL) were measured for lesional and perilesional normal skin of 16 melasma patients and then compared. In addition, a skin biopsy was performed on 11 of the 16 study subjects to measure stratum corneum thickness and to study the protein expressions of PPAR-α and ALOX15B.

RESULTS

Melanin index, erythema index and stratum corneum hydration were significantly higher in lesional skin than in perilesional normal skin. No significant difference was found between lesional and normal skin in terms of basal TEWL level or sebum content. However, the rate of TEWL after barrier perturbation was significantly higher for lesional skin, and the barrier recovery rate was significantly delayed. Furthermore, a trend towards thinned stratum corneum was observed for lesional skin, and this was correlated with barrier recovery rate. The expressions of PPAR-α and ALOX15B were variable in the samples.

CONCLUSIONS

Melasma skin is characterized by impaired stratum corneum integrity and a delayed barrier recovery rate.

The objective evaluation of the severity of psoriatic scales with desquamation collecting tapes and image analysis

BACKGROUND

Assessment of psoriatic scales is important to determine the severity of psoriasis. However, there are very limited numbers of objective, quantitative and observer-independent tools for measuring the severity of psoriasis.

OBJECTIVE

To determine whether the bioengineering parameters of the psoriatic scale can be used to assess the severity of psoriasis instead of the psoriatic severity index of scales (PSIs) score.

METHODS

Thirty-four patients with psoriasis were included. A representative lesion from each patient was selected and bioengineering parameters were measured using the Corneofix(®). Simultaneously, the severity of the scales was assessed by the PSIs score using clinical photographs of the lesions. In addition, skin color and elasticity parameters were also measured using the Colorimeter(®), the Mexameter(®) and the Cutometer(®).

RESULTS

Statistical differences in the scale parameters were observed between the PSIs 2 and 3 scores. Among the scale parameters, the percent area and area in μm(2) were negatively correlated with the PSIs score. In addition, the Colorimeter(®) a, b parameters and the Cutometer(®) R9 parameters were significantly correlated with the PSIs score.

CONCLUSIONS

The results of this study showed that the severity of psoriatic scales could be measured objectively using the Corneofix(®).

Dark green discoloration of the urine after prolonged propofol infusion: a case report

WHAT IS KNOWN AND OBJECTIVE

Propofol, a commonly used sedative, has on rare occasions, been reported to discolour urine green. However, in previous reports, it is uncertain that whether this colour change is dose dependent. We report on a patient who produced dark green discoloration of urine from prolonged propofol infusion, administered for intractable epilepsy.

CASE SUMMARY

The colour intensity of the patient's urine was dependent on propofol infusion rate. Reducing propofol infusion rate lightened the colour of the urine, eventually back to normal.

WHAT IS NEW AND CONCLUSION

Green discoloration of the urine from propofol infusion is dose dependent. It is usually benign and reversible, as was the case for our patient.

Real-time odor discrimination using a bioelectronic sensor array based on the insect electroantennogram

Current trends in artificial nose research are strongly influenced by knowledge of biological olfactory systems. Insects have evolved over millions of years to detect and maneuver toward a food source or mate, or away from predators. The insect olfactory system is able to identify volatiles on a time scale that matches their ability to maneuver. Here, biological olfactory sense organs, insect antennae, have been exploited in a hybrid-device biosensor, demonstrating the ability to identify individual strands of odor in a plume passing over the sensor on a sub-second time scale. A portable system was designed to utilize the electrophysiological responses recorded from a sensor array composed of male or female antennae from four or eight different species of insects (a multi-channel electroantennogram, EAG). A computational analysis strategy that allows discrimination between odors in real time is described in detail. Following a training period, both semi-parametric and k-nearest neighbor (k-NN) classifiers with the ability to discard ambiguous responses are applied toward the classification of up to eight odors. EAG responses to individual strands in an odor plume are classified or discarded as ambiguous with a delay (sensor response to classification report) on the order of 1 s. The dependence of classification error rate on several parameters is described. Finally, the performance of the approach is compared to that of a minimal conditional risk classifier.

A randomized controlled trial of the efficacy and safety of a fixed triple combination (fluocinolone acetonide 0.01%, hydroquinone 4%, tretinoin 0.05%) compared with hydroquinone 4% cream in Asian patients with moderate to severe melasma

BACKGROUND

Melasma is an acquired, chronic hypermelanosis for which therapy remains a challenge.

OBJECTIVES

To compare the efficacy and safety of a triple combination [TC: fluocinolone acetonide 0.01%, hydroquinone (HQ) 4%, tretinoin 0.05%] vs. HQ 4% after 8 weeks of treatment of moderate to severe facial melasma in Asian patients.

METHODS

This was a multicentre, randomized, controlled, investigator-blinded, parallel comparison study. East and South-East Asian patients aged 18 years or older, with a clinical diagnosis of moderate to severe melasma, were enrolled in this study. Patients were enrolled at baseline and treated daily for 8 weeks with TC cream (one application at bedtime) or HQ cream (twice daily). There were four study visits: at baseline and weeks 2, 4 and 8. The primary efficacy variable was the melasma global severity score (GSS). Other outcome measures included Melasma Area and Severity Index, global improvement and patient satisfaction. Safety was assessed through the reporting of adverse events.

RESULTS

TC had superior efficacy to HQ for the primary variable: 77/120 patients (64.2%) on TC had GSS 'none' or 'mild' at week 8 vs. 48/122 patients (39.4%) on HQ (P < 0.001). The secondary efficacy variables confirmed these results. Patient satisfaction was in favour of TC (90/127, 70.8%, vs. 64/129, 49.6%; P = 0.005). More patients had related adverse events on TC (63/129, 48.8%) than on HQ (18/131, 13.7%) but most were mild and none was severe.

CONCLUSIONS

Efficacy in Asians and patient satisfaction were superior with the fixed TC than with HQ 4%.

A case of unilateral hemispheric encephalitis

Herein we report a case of encephalitis involving the unilateral hemisphere, with a clinical course different from that of Rasmussen syndrome. A 44-year-old man visited us because of headache and language abnormality. Cerebrospinal fluid examination showed lymphocytosis with increased level of protein. Brain MRI showed abnormal findings limited to the unilateral hemisphere. The symptoms and signs improved without any specific antiviral treatment in a week. However, language disturbance and right hemiparesis developed after a week. Steroid therapy was effective. He recovered without any neurologic sequelae. Our case was unusual encephalitis involving the unilateral hemisphere, which was benign and steroid-responsive.

Treatment of lipomas assisted with tumescent liposuction

BACKGROUND

Lipoma is a common soft-tissue tumour of mature fat cells. Although surgical excision is effective, treatments that are less invasive and not associated with disfigurement of scar would be ideal for the treatment of lipomas. Recently, tumescent liposuction has been used for the treatment of lipomas.

OBJECTIVE

To evaluate the efficacy of tumescent liposuction in lipoma treatment, we reviewed our experience of lipoma treatment by tumescent liposuction.

METHODS

A total of 21 patients presenting with 31 lipomas were treated with tumescent liposuction. After liposuction, remaining stromas were removed by a haemostat through the small incision. Tumour size and post-operative complications were recorded before and after treatment.

RESULTS

A total of 31 lipomas of 21 patients were treated by tumescent liposuction. The size of lipomas ranged between 1.2 and 11 cm (mean size, 4.1 cm). In 23 cases, there were no complications. However, remnant lipomas, bruise, haematoma and immediate dimpling were found as complications.

CONCLUSION

Tumescent liposuctions with extracting remnant fat tissue and fibrous tissue through the opening for liposuction can be an effective treatment technique in lipoma treatment in the efficacy and cosmetic outcomes and this method can be a substitute for excision in treating large lipomas.

Effects of repetitive superficial chemical peels on facial sebum secretion in acne patients

BACKGROUND

Glycolic acid and Jessner's solution are popular superficial chemical peel agents for the treatment of facial acne, and increased sebum secretion is one of the major aetiological factors of acne.

OBJECTIVE

To compare the effects of 30% glycolic acid peels and Jessner's solution peels on sebum secretion in facial acne patients.

METHODS

Thirty-eight patients with mild to moderate facial acne were included. Twenty-seven patients were treated with 30% glycolic acid peels and 11 patients with Jessner's solution peels. Each peel was performed twice with an interval of 2 weeks. Before and 2 weeks after each peel, sebum levels of forehead, nose, chin and cheeks were measured by using a Sebumeter (SM810 Courage & Khazaka, Cologne, Germany).

RESULTS

The sebum levels were not significantly changed by two peels treatments of 30% glycolic acid peels or Jessner's solution peels on the facial skins of patients with facial acne.

CONCLUSIONS

The two types of peels, 30% glycolic acid peels and Jessner's solution peels, did not affect sebum secretion of the facial skins of patients with facial acne after the two peels treatments. The accumulative effects of more than two peels treatments using these modalities need further evaluation.

Indole-3-carbinol enhances ultraviolet B-induced apoptosis by sensitizing human melanoma cells

Indole-3-carbinol (I3C) has been found to act against several types of cancer, while ultraviolet B (UVB) is known to induce the apoptosis of human melanoma cells. Here, we investigated whether I3C can sensitize G361 human melanoma cells to UVB-induced apoptosis. We examined the effects of combined I3C and UVB (I3C/UVB) at various dosages. I3C (200 microM)/UVB (50 mJ/cm(2)) synergistically reduced melanoma cell viability, whereas I3C (200 microM) or UVB (50 mJ/cm(2)), separately, had little effect on cell viability. DNA fragmentation assays indicated that I3C/UVB induced apoptosis. Further results show that I3C/UVB activates caspase-8, -3, and Bid and causes the cleavage of poly(ADP-ribose) polymerase. Moreover, I3C decreased the expression of the anti-apoptotic protein, Bcl-2, whereas UVB increased the translocation of Bax to mitochondria. Thus, an increased Bax/Bcl-2 ratio by I3C/UVB may result in melanoma apoptosis. In conclusion, our study demonstrated that I3C sensitizes human melanoma cells by down-regulating Bcl-2.

Deafferentation-disconnection neglect induced by posterior cerebral artery infarction

OBJECTIVE

To investigate patients with posterior cerebral artery (PCA) infarctions to learn whether hemispatial neglect is more frequent and severe after right than left PCA infarction; whether visual field defects (VFDs) influence the presence or severity of hemispatial neglect; and the anatomic loci of lesions that are associated with hemispatial neglect.

METHODS

The authors recruited 45 patients with PCA infarction that involved only the occipital lobe or the occipital lobe plus other areas served by the PCA. All subjects received seven neglect tests within 2 months after onset.

RESULTS

Overall, the frequency of hemispatial neglect was 42.2%. The frequency did not significantly differ between the right (48.0%) and left (35.0%) PCA groups, but the severity of hemispatial neglect was significantly greater in the right group. VFD alone did not influence the frequency or severity of neglect after controlling other variables. Isolated occipital lesions were rarely associated with hemispatial neglect, and it was only the occipital plus splenial lesion that significantly influenced the frequency and severity of neglect.

CONCLUSIONS

This study suggests that after excluding such confounding factors as aphasia or hemiplegia, neglect frequency does not differ between the right and left posterior cerebral artery (PCA) groups, but the severity of neglect is greater after right PCA infarctions; even in the acute stage of PCA infarction; visual field defect from an isolated occipital lesion does not cause hemispatial neglect; and the injury to both the occipital lobe and the splenium of the corpus callosum is important for producing hemispatial neglect with PCA infarction.

Does facial sebum excretion really affect the development of acne?

BACKGROUND

It is generally accepted that the severity of acne is correlated with facial sebum secretion. However, previous studies on the relation between seborrhoea and the development of acne did not consider topographical differences in facial sebum secretion and used relatively vague acne severity grading systems.

OBJECTIVES

To elucidate the relation between topographical variations in facial sebum secretion and the severity of acne in women.

METHODS

Forty-six female controls and 46 women with acne were included in this study. The Sebumeter was used to measure facial sebum secretion in the following facial areas: forehead, nose, chin, and right and left cheek. We counted noninflammatory comedones and inflammatory acne lesions in the same areas. We compared sebum secretion between patients with acne and controls, and analysed the relation between the quantity of sebum secreted and the number of acne lesions.

RESULTS

Sebum secretions in the whole face and in the T- and U-zones (areas of high and low sebum secretion, respectively) were higher in patients with acne than in controls. There was no correlation between sebum quantity and acne lesion count in most facial regions.

CONCLUSIONS

Increased levels of facial sebum secretion were observed in patients with acne. Our findings indicate that increased sebum levels do not directly cause development of acne lesions.

Pattern of glucose hypometabolism in frontotemporal dementia with motor neuron disease

Frontotemporal dementia (FTD) often coexists with motor neuron disease (MND). To characterize glucose hypometabolism in patients with FTD with MND (FTD/MND), the authors compared the glucose metabolism of 8 patients with FTD/MND with that of 29 patients with FTD. All of the patients with FTD/MND showed glucose hypometabolism only in the frontal area, whereas most patients with FTD had hypometabolism in the frontal and temporal areas. FTD/MND also showed a more symmetric pattern of glucose hypometabolism than FTD.

Glucose metabolism in early onset versus late onset Alzheimer's disease: an SPM analysis of 120 patients

The aims of this cross-sectional study were (i) to compare the overall glucose metabolism between early onset and late onset Alzheimer's disease in a large sample of patients; and (ii) to investigate the pattern of glucose metabolism as a function of dementia severity in early onset versus late onset Alzheimer's disease, using a statistical parametric mapping (SPM) analysis. Subjects consisted of four groups: 74 patients with early onset Alzheimer's disease, 46 patients with late onset of the disease, and two control groups age matched to each patient group. All the subjects underwent 2-[(18)F]fluoro-2-deoxy-d-glucose (FDG)-PET under the same scanning conditions. Severity of dementia was rated with the Clincial Dementia Rating (CDR). Voxel-based SPM99 was used for statistical analyses. Overall glucose hypometabolism of early onset Alzheimer's disease patients was much greater in magnitude and extent than that of late onset patients, though both groups were similar in dementia severity: the early onset group showed more severe hypometabolism in parietal, frontal and subcortical (basal ganglia and thalamus) areas. When the decline of glucose metabolism was compared as a function of CDR stage, the slope was steeper in early onset than in late onset Alzheimer's disease. The rapid decline occurred at CDR 0.5-1 in the early onset group, whereas similar changes occurred at CDR 2-3 in the late onset group. The greater hypometabolism in early onset than in late onset patients is required to reach the same severity of dementia, probably reflecting greater functional reserve in younger than in older subjects. Alternatively, the metabolic decline curve suggests that the early onset patients may take a more rapid course in the reduction of glucose metabolism than the late onset patients.

Terrein: a new melanogenesis inhibitor and its mechanism

Terrein is a bioactive fungal metabolite whose effects are almost unknown. In this study, we found for the first time that terrein has a strong hypopigmentary effect in a spontaneously immortalized mouse melanocyte cell line, Mel-Ab. Treatment of Mel-Ab cells with terrein (10-100 microM) for 4 days significantly reduced melanin levels in a dose-dependent manner. In addition, terrein at the same concentration also reduced tyrosinase activity. We then investigated whether terrein influences the extracellular signal-regulated protein kinase (ERK) pathway and the expression of microphthalmia-associated transcription factor (MITF), which is required for tyrosinase expression. Terrein was found to induce sustained ERK activation and MITF down-regulation, and luciferase assays showed that terrein inhibits MITF promoter activity in a dose-dependent manner. To elucidate the correlation between ERK pathway activation and a decreased MITF transcriptional level, PD98059, a specific inhibitor of the ERK pathway, was applied before terrein treatment and found to abrogate the terrein-induced MITF attenuation. Terrein also reduced the tyrosinase protein level for at least 72 h. These results suggest that terrein reduces melanin synthesis by reducing tyrosinase production via ERK activation, and that this is followed by MITF down-regulation.

Isolation of human epidermal stem cells by adherence and the reconstruction of skin equivalents

The isolation of human epidermal stem cells is critical for their clinical applications. In the present study, we isolated three populations of epidermal keratinocytes according to their ability to adhere to collagen type IV: i.e., rapidly adhering (RA), slowly adhering (SA), and non-adhering (NA) cells. The aim of this study was to characterize RA cells and to investigate the possibility of using these cells for epidermis reconstruction. To identify RA cells, flow cytometric analysis was performed using anti-alpha(6) integrin and anti-CD71 antibodies. RA cells express high levels of alpha(6) integrin and low levels of CD71, which are considered as markers of an epidermal stem cell nature. Furthermore, electron microscopy showed that RA cells are small and have a high nuclear to cytoplasmic ratio, whereas SA and NA cells have well-developed cellular organelles and abundant tonofilaments. Western blot analysis showed that RA cells are slow cycling and express p63, a putative epidermal stem cell marker, whereas SA and NA cells express c-Myc, which is known to regulate stem cell fate. To compare epidermal regenerative abilities, skin equivalents (SEs) were made using RA, SA, and NA cells. The epidermis constructed from RA cells was well formed compared to those formed from SA or NA cells. In addition, only SEs with RA cells expressed alpha(6) integrin and beta(1) integrin at the basal layer. These results indicate that RA cells represent epidermal stem cells and are predominately comprised of stem cells. Therefore, the isolation of RA cells using a simple technique offers a potential route to their clinical application, because they are easily isolated and provide a high yield of epidermal stem cells.

Normal rainbow trout serum (RTS)-resistant variants of the infectious pancreatic necrosis virus (IPNV)-Jasper differ with respect to inhibition by RTS, serotype and cDNA sequence

In order to determine if the infectious pancreatic necrosis virus isolate IPNV-Jasper (Ja-ATCC) is homogeneous or heterogeneous with respect to inhibition by normal rainbow trout serum (RTS), 50 clones were tested for sensitivity to RTS. The initial isolate was very sensitive to RTS, losing from 10(4) to 10(8) 50 % tissue culture infection dose (TCID50) ml(-1) with a 1:100 dilution of RTS. The sensitivity of the clones ranged from highly sensitive to completely resistant (0 to 10(8) TCID50 ml(-1) reduction). Eight percent of clones (4/50) were very sensitive to RTS (Ja-S) and 84% of clones (42/50) showed a mid-range of sensitivity to RTS. The final 8 % of clones (4/50) were resistant to RTS (Ja-R). Enzyme immunodot assay revealed that Ja-S clones showed a monoclonal reaction identical to the parents, Ja-ATCC; however, Ja-R clones differed by several epitopes from the parental strain. Analysis of Ja-S and Ja-R revealed that there were significant differences in their nucleic acid sequences for the capsid protein VP2. These 2 strains shared 80.7 and 86.5% identity in nucleic acid and in amino acid sequences, respectively. Ja-S had 99.7 and 91.0 % identity in nucleic acid sequences, and 99.5 and 95.9 % in amino acid sequences with Ja-ATCC and Jasper-Dobos (Ja-D), respectively, while Ja-R showed 80.6 and 79.8 % identity in nucleic acid sequences and 86.5 and 87.0 % in amino acid sequences with Ja-ATCC and Ja-D, respectively. In conclusion, the Ja-ATCC population was heterogeneous in terms of RTS sensitivity, serotype and cDNA sequences from the VP2 coding region.

Attentional bias induced by viewing actual or illusory movements

Objective: To learn to which portions of a line normal subjects would attend when watching this line actually moving or when perceiving movement even in the absence of actual movement, an illusory movement.

Methods: Twenty normal subjects watched a computer monitor on which either lines or dots moved to the right or left. They also watched stationary lines, which appeared to be moving to the left or right because the background was moving in the opposite direction. While watching these lines or dots, their eye movements were monitored to determine the position of fixation.

Results: Overall, subjects fixated on the side of the line that was in the direction of real or illusory movement. In the actual movement condition, leftward motion induced more of an attentional bias than rightward motion. In the illusory movement condition, however, rightward illusory movement condition induced more of an attentional bias than leftward movement.

Conclusions: Objects moving leftward or rightward primarily activate the contralateral hemisphere. This hemispheric activation may induce a contralateral overt orienting response that is reflected by eccentric eye fixation. Treatments of neglect, such as caloric vestibular stimulation, may alter an attentional bias by inducing the illusion of movement.

Dietary supplementation of (+)-catechin protects against UVB-induced skin damage by modulating antioxidant enzyme activities

PURPOSE

The aim of this study was to investigate the effects of dietary supplementation with (+)-catechin on cutaneous antioxidant enzymes and the skin damage caused by UVB irradiation.

METHODS

BALB/c mice were divided into three groups. Each group was fed a regular diet (RD) or a 2% catechin-supplemented diet for either 2 weeks (2CSD) or 4 weeks (4CSD) ad libitum prior to UVB irradiation. Skin was removed for the antioxidant enzyme assay, hematoxylin and eosin staining, and the TEM analysis before and at various time points after UVB (200 mJ/cm2) irradiation.

RESULTS

Before UVB irradiation, the superoxide dismutase (SOD) and catalase (CAT) activities of the 2CSD and the 4CSD groups were found to be lower than those of the RD group, whereas the glutathione peroxidase (GPx) activity of the 4CSD group was higher than those of the RD and the 2CSD groups (P<0.05). The SOD and CAT activities of the RD group decreased after UVB irradiation, while those of the 2CSD and the 4CSD groups increased immediately after irradiation and then decreased (P<0.05). Immediately after UVB irradiation, the GPx activities of the 4CSD and the 2CSD groups increased, but that of the RD group decreased. The GPx activity of all three groups showed a tendency to return to pre-UVB irradiation levels with time. Light microscopic findings of the RD group showed epidermal thinning and apoptotic cells at 24 h after UVB irradiation and mostly necrotic cells at 48 h, whereas only moderate thickening of the epidermis was observed in the 2CSD group at 48 h after irradiation. An electron microscopic examination produced similar findings. At 48 h after irradiation, nearly all epidermal cells seemed to be damaged in the RD group as compared to the 2CSD group.

CONCLUSION

These results demonstrate that dietary supplementation with (+)-catechin could protect epidermal cells against UVB-induced damage by modulating antioxidant enzyme activities.

Genetic variations of AA genome Oryza species measured by MITE-AFLP

MITEs (miniature inverted-repeat transposable elements) are the major transposable elements in Oryza species. We have applied the MITE-AFLP technique to study the genetic variation and species relationship in the AA-genome Oryza species. High polymorphism was detected within and between species. The genetic variation in the cultivated species, Oryza sativa and Oryza glaberrima, was comparatively lower than in their ancestral wild species. In comparison between geographical lineages of the AA genome species, African taxa, O. glaberrima and Oryza barthii, showed lower variation than the Asian taxa, O. sativa, Oryza rufipogon, and Oryza nivara, and Australian taxon Oryza meridionalis. However, another African taxon, Oryza longistaminata, showed high genetic variation. Species relationships were analyzed by the pattern of presence or absence of homologous fragments, because nucleotide sequences of the detected MITE-AFLP fragments revealed that the same fragments in different species shared very high sequence homology. The clustering pattern of the AA-genome species matched well with the geographical origins (Asian, African and Australian), and with the Australian taxon being distant to the others. Therefore, this study demonstrated that the MITE-AFLP technique is amenable for studying the genetic variation and species relationship in rice.

The culture of safety: results of an organization-wide survey in 15 California hospitals

OBJECTIVE

To understand fundamental attitudes towards patient safety culture and ways in which attitudes vary by hospital, job class, and clinical status.

DESIGN

Using a closed ended survey, respondents were questioned on 16 topics important to a culture of safety in health care or other industries plus demographic information. The survey was conducted by US mail (with an option to respond by Internet) over a 6 month period from April 2001 in three mailings.

SETTING

15 hospitals participating in the California Patient Safety Consortium.

SUBJECTS

A sample of 6312 employees generally comprising all the hospital's attending physicians, all the senior executives (defined as department head or above), and a 10% random sample of all other hospital personnel. The response rate was 47.4% overall, 62% excluding physicians. Where appropriate, responses were weighted to allow an accurate comparison between participating hospitals and job types and to correct for non-response.

MAIN OUTCOME MEASURES

Frequency of responses suggesting an absence of safety culture ("problematic responses" to survey questions) and the frequency of "neutral" responses which might also imply a lack of safety culture. Responses to each question overall were recorded according to hospital, job class, and clinician status.

RESULTS

The mean overall problematic response was 18% and a further 18% of respondents gave neutral responses. Problematic responses varied widely between participating institutions. Clinicians, especially nurses, gave more problematic responses than non-clinicians, and front line workers gave more than senior managers.

CONCLUSION

Safety culture may not be as strong as is desirable of a high reliability organization. The culture differed significantly, not only between hospitals, but also by clinical status and job class within individual institutions. The results provide the most complete available information on the attitudes and experiences of workers about safety culture in hospitals and ways in which perceptions of safety culture differ among hospitals and between types of personnel. Further research is needed to confirm these results and to determine how senior managers can successfully transmit their commitment to safety to the clinical workplace.

Host plant volatiles synergize responses of sex pheromone-specific olfactory receptor neurons in male Helicoverpa zea

Single-cell electrophysiological recordings were obtained from olfactory receptor neurons in antennal trichoid sensilla of male corn earworm, Helicoverpa zea. Spontaneous activity of the neuron specific for the major component ( Z)-11-hexadecenal, the conspecific female-emitted sex pheromone, was not affected by exposure to host plant volatiles. However, stimulations with binary mixtures of a threshold dosage of the pheromone component and increasing dosages of either linalool or ( Z)-3-hexenol significantly synergized the pheromone-specific neuron's firing rates compared with responses to the major pheromone component alone. Cross-adaptation studies confirmed that the enhanced impulses originated from the pheromone-component-tuned neuron. Because plant volatiles do not stimulate the pheromone-specific neuron when presented alone, the pheromone plus host odor blend would be interpreted as containing more pheromone than it actually does when processed by the pheromone-processing portion of the antennal lobe.

Modulation of skin collagen metabolism in aged and photoaged human skin in vivo

To the best of our knowledge, no study has been conducted to date to directly compare the collagen metabolism of photoaged and naturally aged human skin. In this study, we compared collagen synthesis, matrix metalloproteinase-1 levels, and gelatinase activity of sun-exposed and sun-protected skin of both young and old subjects. Using northern blot analysis, immunohistochemical stain, and Western blot analysis, we demonstrated that the levels of procollagen type I mRNA and protein in photoaged and naturally aged human skin in vivo are significantly lower than those of young skin. Furthermore, we demonstrated, by northern blot analysis, that the procollagen alpha1(I) mRNA expression of photoaged skin is much greater than that of sun-protected skin in the same individual. In situ hybridization and immunohistochemical stain were used to show that the expression of type I procollagen mRNA and protein in the fibroblasts of photoaged skin is greater than for naturally aged skin. In addition, it was found, by Western blot analysis using protein extracted from the dermal tissues, that the level of procollagen type I protein in photoaged skin is lower than that of naturally aged skin. The level of matrix metalloproteinase-1 protein and the activity of matrix metalloproteinase-2 were higher in the dermis of photoaged skin than in naturally aged skin. Our results suggest that the natural aging process decreases collagen synthesis and increases the expression of matrix metalloproteinases, whereas photoaging results in an increase of collagen synthesis and greater matrix metalloproteinase expression in human skin in vivo. Thus, the balance between collagen synthesis and degradation leading to collagen deficiency is different in photoaged and naturally aged skin.

Aging- and photoaging-dependent changes of enzymic and nonenzymic antioxidants in the epidermis and dermis of human skin in vivo

This is a comprehensive study of the changes in major antioxidant enzymes and antioxidant molecules during intrinsic aging and photoaging processes in the epidermis and dermis of human skin in vivo. We show that the activities of superoxide dismutase and glutathione peroxidase are not changed during these processes in human skin in vivo. Interestingly, the activity of catalase was significantly increased in the epidermis of photoaged (163%) and naturally aged (118%) skin (n = 9), but it was significantly lower in the dermis of photoaged (67% of the young skin level) and naturally aged (55%) skin compared with young (n = 7) skin. The activity of glutathione reductase was significantly higher (121%) in naturally aged epidermis. The concentration of alpha-tocopherol was significantly lower in the epidermis of photoaged (56% of young skin level) and aged (61%) skin, but this was not found to be the case in the dermis. Ascorbic acid levels were lower in both epidermis (69% and 61%) and dermis (63% and 70%) of photoaged and naturally aged skin, respectively. Gluta thione concentrations were also lower. Uric acid did not show any significant changes. Our results suggest that the components of the antioxidant defense system in human skin are probably regulated in a complex manner during the intrinsic aging and photoaging processes.

Downregulation of Bcl-2 and activation of caspase-8 in the UVB-induced apoptosis of a cultured human melanoma cell line

PURPOSE

This study was performed to determine the effect of UV radiation on the activation of apoptosis regulatory proteins using cultured human melanoma cells.

METHODS

G361 lightly pigmented melanoma cells were irradiated with increasing doses of UVB and analyzed for an apoptotic mechanism using a cell viability test, TEM, FACS, and western blotting analysis.

RESULTS

TEM and FACS showed apoptotic features of cell death after UVB irradiation. Western blotting disclosed downregulation of Bcl-2 and the activation of caspase-9. Caspase-8, a downstream molecule of Fas/FasL interaction, was also activated. The activation of downstream molecules of both caspase-8 and caspase-9 was also demonstrated.

CONCLUSION

Our data showed that the regulation of the Bcl-2 family and caspase-8 may work together to activate a caspase-3 mediated apoptotic pathway following UVB irradiation of cultured human melanoma cells.

Cutaneous photodamage in Koreans: influence of sex, sun exposure, smoking, and skin color

BACKGROUND

Severe wrinkles and pigmentary changes of the exposed skin indicate substantial damage due to UV radiation. Many investigators believe that the principal manifestation of photodamage in Asians is pigmentary change rather than wrinkles. However, to our knowledge, no well-designed study has investigated the characteristics of cutaneous photodamage in Asian skin.

OBJECTIVE

To access the severity of wrinkles and dyspigmentation in Koreans exposed to sun and who smoked.

METHODS

We developed new photographic scales for grading wrinkles and dyspigmentation in 407 Koreans to assess the severity of the wrinkles and dyspigmentation. We interviewed subjects to determine cumulative sun exposure and smoking history, and measured the skin color of individual subjects.

RESULTS

Our photographic scales provided a reliable evaluation of photodamage severity in Koreans. The pattern of wrinkling in both sexes is similar, but women tended to have more severe wrinkles (prevalence odds ratio, 3.7). However, the pattern of dyspigmentation differed between the sexes. Seborrheic keratosis is the major pigmentary lesion in men, whereas hyperpigmented macules are the prominent features in women. Cigarette smoking is an independent risk factor for wrinkles, but not for dyspigmentation, in Koreans, and causes additive detrimental effects to wrinkles induced by aging and sun exposure. The constitutive skin color did not show any correlation with wrinkles or dyspigmentation. However, facultative pigmentation (sun exposure index) may reflect lifetime sun exposure, and it shows a good correlation with wrinkles in Koreans.

CONCLUSION

Wrinkling is a major feature of photoaging in Koreans, as are pigmentary changes; smoking, sun exposure, and female sex are independent risk factors for wrinkles.

Ultraviolet radiation increases tropoelastin mRNA expression in the epidermis of human skin in vivo

Photoaged skin contains elastotic materials in the upper reticular dermis. This phenomenon is commonly known as solar elastosis. Little is known about the mechanisms leading to the accumulation of elastotic materials in photoaged skin, however. In this study, it was demonstrated that ultraviolet irradiation induced tropoelastin mRNA expression in the keratinocytes of human skin in vivo and also in cultured human keratinocytes by in situ hybridization and reverse transcriptase polymerase chain reaction. It was also shown by northern blot analysis (n = 5) that there were increased tropoelastin mRNA levels in the forearm (sun-exposed) skin of elderly persons, compared with upper-inner arm (sun-protected) skin of the same individuals. As demonstrated by in situ hybridization compared to sun-protected skin (upper-inner arm) (n = 5), tropoelastin mRNA expression in photoaged skin was higher in keratinocytes as well as in fibroblasts. Therefore, our results suggest that keratinocytes are another source of tropoelastin production after acute and chronic ultraviolet irradiation in human skin in vivo.

Effects of collagen IV and laminin on the reconstruction of human oral mucosa

To investigate the effects of basement membrane proteins on the reconstruction of mucosa equivalent, oral mucosa substitute were cultured on (1) type I collagen gels, (2) type IV collagen-coated type I collagen gels, (3) laminin-coated type I collagen gels, and (4) type I collagen gels containing both type IV collagen and laminin. H/E and PAS staining showed that the characteristics of the oral mucosa were preserved under all the experimental conditions. However, the basal keratinocytes appeared cuboidal when the type I collagen gels were coated with type IV collagen plus laminin. The expression of the differentiation markers was similar, but weak staining of filaggrin, K13, and involucrin was observed with the type IV collagen plus laminin coating. Furthermore, electron microscopy revealed that the size of the basal keratinocytes was relatively small and uniform when both type IV collagen and laminin were used. These findings suggested that these two major basement membrane proteins are important in the process of differentiation in mucosal keratinocytes.

Induction of alpha1-acid glycoprotein mRNA by cytokines and differentiation in human colon carcinoma cell

The mRNA for the alpha1-acid glycoprotein (AAG) was expressed not only in hepatoma cells, but also in non-hepatic cancer cells. The expression of the AAG mRNA in HT-29 human colon carcinoma cells is induced by cytokines, IL-6, IL-1, and TNF-alpha, in a manner characteristic of the acute phase response, and the expression of AAG mRNA was up-regulated in differentiated HT-29 cells.

Ceramide inhibits cell proliferation through Akt/PKB inactivation and decreases melanin synthesis in Mel-Ab cells

Ceramide is a bioactive sphingolipid that mediates a variety of cell functions. However, the effects of ceramide on cell growth and the melanogenesis of melanocytes are not known. In the present study, we investigated the actions of cell-permeable ceramide and its possible role in the signaling pathway of a spontaneously immortalized mouse melanocyte cell line, Mel-Ab. Our results show that C2-ceramide inhibits DNA synthesis in Mel-Ab cells and G361 human melanoma cells in a dose-dependent manner. Cell cycle analysis confirmed the inhibition of DNA synthesis by a reduction in the S phase. To investigate the ceramide signaling pathway, we studied whether C2-ceramide is able to influence extracellular signal-regulated kinase (ERK) and/or Akt/protein kinase B (PKB) activation. We demonstrated that phosphorylated Akt/PKB is decreased by C2-ceramide, whereas phosphorylated ERK was only slightly affected. Therefore, the C2-ceramide-induced inactivation of Akt/PKB may be closely related to the reduced cell proliferation of Mel-Ab cells. Furthermore, we assessed the effects of C2-ceramide on the pigmentation of Mel-Ab cells. The results obtained showed that the melanin content of cells was significantly reduced by C2-ceramide at concentrations in the range of 1-10 microM, and that the pigmentation-inhibiting effect of C2-ceramide is much greater than that of kojic acid at 1-100 microM. In addition, we found that the activity of tyrosinase is reduced by C2-ceramide treatment. Our results demonstrate that C2-ceramide reduces the pigmentation of Mel-Ab cells by inhibiting tyrosinase activity.

Decision analysis for the cost-effective management of recurrent colorectal cancer

OBJECTIVE

To determine whether the use of [(18)F]2-fluoro-2-deoxyglucose positron emission tomography (FDG PET) in addition to computed axial tomography (CT) is helpful in managing recurrent colorectal cancer (CRC).

SUMMARY BACKGROUND DATA

There is no consensus on a management algorithm for CRC. However, when recurrence is suspected, CT is generally used for further evaluation and staging of disease.

METHODS

The authors used decision trees based on theoretical models to assess the cost-effectiveness of a CT + FDG PET strategy for the diagnosis and management of recurrent CRC compared with a CT-alone strategy. These theoretical models focus on patients with hepatic recurrence who are potentially curable through surgical hepatic resection. The population entering the decision trees consisted of patients with CRC who had undergone surgical resection of their primary CRC and who were suspected of having recurrence based on elevated levels of carcinoembryonic antigen.

RESULTS

The CT + FDG PET strategy was found to be cost-effective for managing patients with elevated carcinoembryonic antigen levels who were candidates for hepatic resection. The CT + FDG PET strategy was higher in mean cost by $429 per patient but resulted in an increase in the mean life expectancy of 9.527 days per patient.

CONCLUSIONS

These results show, through rigorous decision tree analysis, the potential cost-effectiveness of FDG PET in the management of recurrent CRC. The decision trees can be used to model various features of the management of recurrent CRC, including the cost-effectiveness of other newly emerging technologies.

Growth related secretion and production of GM-CSF by epithelial cell line

Granulocyte-macrophage colony stimulating factor (GM-CSF) is a growth factor that supports the clonal development of normal granulocyte-macrophage progenitors. Especially in the skin, GM-CSF from keratinocytes may be a critical factor in the melanogenesis of the skin. In addition, GM-CSF is thought to play an important role in impaired wound healing. However, little is known regarding the synthesis and secretion of GM-CSF by keratinocytes of the skin. This investigation evaluated the effects of cell density on the production of GM-CSF by keratinocytes and the changes in the cell cycle. Interestingly, GM-CSF protein secretions and mRNA expressions were highly elevated in sub-confluent HaCat cells, and decreased in confluent state. In particular, GM-CSF production decreased in a density-dependent manner. We also found that the percentage of cells in the S phase of the cell cycle decreased markedly from 50 to 10% when HaCat cells reached a confluent state. These results showed that GM-CSF synthesis and secretion by HaCat cells increases when cells are rapidly proliferating such as in the wound healing process. Thus, it might be said that GM-CSF produced by proliferating keratinocytes possibly contributes to wound healing and melanogenesis at the site of injury.