Lack of association between COPD and transforming growth factor-beta1 (TGFB1) genetic polymorphisms in Koreans

OBJECTIVE

Many genetic variations have been suggested as genetic risk factors for the development of chronic obstructive pulmonary disease (COPD), including single nucleotide polymorphisms in the transforming growth factor-beta1 (TGFB1) gene. We attempted to elucidate the association between TGFB1 genetic polymorphisms and COPD among Koreans.

DESIGN

The genotypes of 102 male patients with COPD and 159 volunteers with similar distributions of age, sex and smoking intensity, as well as normal pulmonary function, were determined for three previously associated TGFB1 single nucleotide polymorphisms (SNPs), -10807G/A (rs2241712) and -509T/C (rs1800469), located in or near the promoter, and 29T/C (rs1982073), located in exon 1 of the TGFB1 gene.

RESULTS

No significant associations between COPD and the three TGFB1 SNPs could be identified. In addition, the haplotypes composed of three TGFB1 SNPs were not associated with the presence of COPD.

CONCLUSION

These results differ from previous reports involving Caucasians, and might reflect racial differences in the pathogenesis of COPD.

The association between microsatellite polymorphisms in intron II of the human Toll-like receptor 2 gene and tuberculosis among Koreans

The observation that Toll-like receptor (TLR)2-deficient mice are highly susceptible to mycobacteria suggests that mutations altering TLR2 expression may impair host response to Mycobacterium tuberculosis. We evaluated the association between guanine-thymine (GT) repeat polymorphism in intron II of the TLR2 gene and the presence of tuberculosis (TB) in Koreans. The numbers of GT repeats were determined by PCR and gene scans for 176 TB patients and 196 controls. The recombinant TLR2 promoter/exonI/exonII/intronII/luciferase constructs including three representative repeats: (GT)13, (GT)20, and (GT)24 were transfected into K562 cells, and luciferase activities were estimated and compared. The expression of TLR2 on CD14+ peripheral blood mononuclear cells (PBMC) from healthy volunteers were measured with flow cytometry. Genotypes with shorter GT repeats were more common among TB patients (49.4 vs 37.7%, P=0.02). This observation was confirmed among 82 other TB patients as a validation cohort. Shorter GT repeats were associated with weaker promoter activities and lower TLR2 expression on CD14+ PBMCs. In conclusion, the development of TB disease in Koreans was associated with shorter GT repeats in intron II of the TLR2 gene. This association is correlated with lower expression of TLR2 through weaker promoter activity for genes with shorter GT repeats.

The effect of human bone marrow stromal cells and dermal fibroblasts on angiogenesis

BACKGROUND

A cell therapy methodology for angiogenesis using fibroblasts has already been developed. Bone marrow stromal cells, which contain mesenchymal stem cells, have a low rate of immunity-assisted rejection and are capable of expanding profoundly in culture. Therefore, these cells offer several advantages for transplantation over mature cells. The aim of this study was to compare the angiogenic activity of bone marrow stromal cells with that of fibroblasts.

METHODS

For in vitro study, cultured human bone marrow stromal cells and dermal fibroblasts were seeded onto 96-well culture plates. After 1, 3, and 5 days, the levels of the basic fibroblast growth factor and vascular endothelial growth factor were compared. For in vivo study, porous polyethylene disks were loaded with bone marrow stromal cells, fibroblasts, or no cells and then implanted in the backs of rats. At three time intervals ranging from 1 to 3 weeks, the microvascular density was measured.

RESULTS

In the in vitro study, the basic fibroblast growth factor levels in the bone marrow stromal cell group were 47, 89, and 68 percent higher than in the fibroblast group at each time interval (p < 0.05). The vascular endothelial growth factor levels of the bone marrow stromal cell group were seven, 12, and 12 times higher than those of the fibroblast group (p < 0.05). In the in vivo study, there was little difference in the microvascular density among the three groups by the second week. However, the 3-week specimens showed a significantly greater difference. The microvascular density averaged 52.88, 26.12, and 17.50 for the bone marrow stromal cell, fibroblast, and no-cell groups, respectively.

CONCLUSION

These results suggest that bone marrow stromal cells may possibly be used as a replacement for fibroblasts for angiogenesis.

Augmentation Rhinoplasty Using Injectable Tissue-Engineered Soft Tissue

In a previous animal study, the authors reported that cultured human fibroblasts suspended in Restylane, which is a modified hyaluronic acid, can produce human dermal matrices with extended in vivo stability. This study was undertaken to evaluate the clinical efficacy of this method, particularly for augmentation rhinoplasty cases. Between January 2002 and June 2003, 11 patients were treated with subcutaneous implants of Restylane mixed with autologous fibroblasts for augmentation rhinoplasty. Of these 11 patients, a long-term follow-up for more than 1 year was possible in 6 patients. Appearance of reconstructed noses, degree and time of resorption, occurrence of complications, and patients' satisfaction were investigated. The injected implants remained in situ without evidence of significant resorption or loss of correction. All patients were satisfied with the achieved long-term results, and no complication occurred. The results obtained indicate that this method is well tolerated and may have a potential to be an effective means of performing augmentation rhinoplasty.

Simultaneous treatment of sewage sludge and food waste by the unified high-rate anaerobic digestion system

This study aimed to evaluate the performance of the unified high-rate anaerobic digestion (UHAD) system treating co-substrate of sewage sludge and food waste. A 24-hr operating sequence consisted of four steps including fill, react, settle, and draw. The effects of co-substrate and organic loading rate (OLR) on the performance were investigated to verify the system applicability. In each OLR, the UHAD system showed higher CH4 recovery (> 70%), CH4 yield (0.3 L CH4/g VSadded) and CH4 production rate (0.6 L CH4/L/d) than the control system. In the specific methanogenic activity (SMA) tests on thermophilic biomass of the UHAD system, the average SMA of acetate (102 mL CH4/gVSS/d) was much higher than those of butyrate (85 mL CH4/g SS/d) and propionate (42 mL CH4/gVSS/d). It was demonstrated that the UHAD system for co-digestion resulted in higher methane yield and methane production rate due to sequencing batch operation, thermophilic digestion, and co-digestion. The enhanced performance could be attributed to longer retention time of active biomass, faster hydrolysis, higher CH4 conversion rate, and balanced nutrient conditions of co-substrate in the UHAD system. Consequently, this optimized unification could be a viable option for the simultaneous treatment of two types of OFMSW with high stability.

Impact of fluoroquinolones on the diagnosis of pulmonary tuberculosis initially treated as bacterial pneumonia

OBJECTIVE

The excellent in vitro activity of fluoroquinolones against Mycobacterium tuberculosis has raised concerns about the delayed diagnosis of pulmonary tuberculosis (PTB) initially misdiagnosed as pneumonia. The aim of this study was to assess the effect of empiric fluoroquinolone therapy on delays in diagnosis in patients with PTB initially misdiagnosed as bacterial pneumonia.

DESIGN

Patients with PTB initially treated as having community-acquired pneumonia and treated with fluoroquinolones for more than 5 consecutive days, from January 2000 to December 2004, were enrolled. As a control group, TB patients initially treated with nonfluoroquinolone antibiotics were enrolled. We reviewed the clinical data and compared treatment responses between the two groups.

RESULTS

Nine patients in the fluoroquinolone group and 19 patients in the non-fluoroquinolone group were enrolled. In the fluoroquinolone group, eight patients (89%) improved clinically or radiographically, whereas only eight patients (42%) in the non-fluoroquinolone group improved (P = 0.04). The delay in initiation of anti-tuberculosis medication was longer in the fluoroquinolone group than in the non-fluoroquinolone group (43.1 - 40.0 vs. 18.7 +/- 16.9 days, P = 0.04).

CONCLUSION

Delay in the initiation of anti-tuberculosis treatment is possible in patients administered fluoroquinolone and initially misdiagnosed as having bacterial pneumonia.

Potential of Human Bone Marrow Stromal Cells to Accelerate Wound Healing in Vitro

The purpose of this pilot study was to compare proliferation, collagen synthesis, and growth factor production, which are important contributing factors for wound healing, of the bone marrow stromal cells (BSCs) with those of dermal fibroblasts in vitro. Cultured human BSCs and dermal fibroblasts from the same patients were seeded in 96-well culture plates. At 1, 3, and 5 days postincubating, cell proliferation, collagen synthesis, and secretion of basic fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGF), and transforming growth factor beta (TFG-beta) were compared. We did not observe great differences in cell proliferation and TFG-beta secretion. In contrast, the amount of collagen synthesis and the levels of the bFGF and the VEGF were much higher in the BSC group than the fibroblast group at each time interval (P < 0.05). Our results suggest that the BSCs may have superior potential to accelerate wound healing than the fibroblasts.

The Fate of Microanastomosed Digital Arteries after Successful Replantation

BACKGROUND

Some replanted fingers show occlusion of the anastomosed arteries, although they are successfully replanted and ultimately survive. They seem to be perfused by the soft-tissue vasculature and not by the anastomosed arteries. Therefore, this study was designed to investigate the fate of microanastomosed digital arteries after successful replantation.

METHODS

The authors performed a prospective study of 75 fingers of 62 cooperative patients who had undergone successful replantation from June of 2000 to December of 2001 at Korea University Guro Hospital. We used Dopplex to screen anastomosed artery patency; thereafter, angiographic studies were also performed to confirm the Dopplex results in 18 patients. The patency of vascular pedicles was analyzed according to several parameters, namely, the cause, type, and level of injury; the number of repaired veins; and the use of an interpositional vein graft for arterial repair.

RESULTS

The pulsation was not heard by Dopplex in 37 percent of anastomosed arteries after an average of 15 postoperative days. Angiographic results coincided with Dopplex results in all cases. Guillotine injuries had a pedicle occlusion rate of 8 percent, whereas crush injuries had a pedicle occlusion rate of 43 percent (p < 0.05). Regarding the level of injury, a statistically significant difference was only found between groups with a distal phalanx level of injury and those with a proximal phalanx level of injury (p < 0.05). Other parameters showed no significant differences in patency.

CONCLUSIONS

We conclude that 37 percent of microanastomosed digital arteries of replanted fingers are occluded after replantation. Distinctively, amputation at the distal phalanx by crush injury increases the possibility of occlusion of microanastomosed digital arteries.

The effect of releasing tip-supporting structures in short-nose correction

Correction of a short nose has been regarded as one of the most challenging and at times vexing procedures in rhinoplasty. One surgical option used to prolong nasal length is the freeing of the alar cartilages from adjacent structures by dividing the nasal tip supporting tissues. Five fibrous connections are known to be important in maintaining the nasal tip shape: fibrous tissues between the upper lateral and lower lateral cartilages; the lateral border of the lower lateral cartilages at the pyriform aperture; the interdormal ligament and anterior septal angle; the footplate of the medial crus and septal cartilage; and the dermocartilaginous ligament. This study was designed to determine which of the fibrous connections providing nasal tip support offer the most effect of lengthening when these structures are divided. We performed 10 open rhinoplasties on fresh cadavers, and we sequentially divided the previously mentioned tip-supporting structures, except the dermocartilaginous ligament. The mucoperichondrium of the upper lateral and septal cartilages was also elevated, in accordance with the usual order of being released in a short-nose correction procedure. We measured the distance between the anterior septal angle and tip-defining points by using calipers while the middle crura of the lower lateral cartilages were stretched with a skin hook. We found that the most effective length was gained by severing the lateral crus from the upper lateral cartilages, and moderate gain was noted from the release at the pyriform aperture and mucoperichondrium of the upper lateral cartilage. Release of other tip-defining structures was not statistically effective.

Interstitial lung disease in patients with polymyositis, dermatomyositis and amyopathic dermatomyositis

OBJECTIVE

To assess the prevalence, characteristics and prognostic factors of interstitial lung disease (ILD) in Korean patients with polymyositis (PM), dermatomyositis (DM) and amyopathic dermatomyositis (ADM).

METHODS

We reviewed the medical records of 72 consecutive PM and DM patients, including six patients with ADM, who were seen at the Rheumatology Clinic of Seoul National University Hospital between 1984 and 2003.

RESULTS

Twenty-nine PM/DM patients (40.3%) developed ILD. Anti-Jo-1 antibody and arthralgia were associated with the presence of ILD (P = 0.022 and P = 0.041, respectively), whereas dysphagia was more frequently found in patients without ILD (P = 0.041). Lung biopsies revealed diffuse alveolar damage (DAD) (n = 2), usual interstitial pneumonia (UIP) with DAD (n = 2), UIP (n = 1), and non-specific interstitial pneumonia (n = 2). Of the 29 patients, 11 (37.9%) died. The mean survival time in ILD patients was significantly shorter than in those without ILD (13.8+/-1.8 vs 19.2+/-0.9 yr, P = 0.017). Poor survival in ILD patients was associated with a Hamman-Rich-like presentation (P = 0.0000), ADM features (P = 0.0001) and an initial forced vital capacity (FVC) < or =60% (P = 0.024).

CONCLUSIONS

ILD was observed in 40.3% of Korean PM/DM patients and was associated with poor survival. A Hamman-Rich-like presentation, ADM features and an initial FVC < or =60% were associated with poor survival in ILD.

Anatomy of the external nasal nerve

After rhinoplasty, many patients report numbness of the nasal tip. This is primarily because of injury to the external nasal nerve. It is imperative that surgeons performing rhinoplasty be familiar with the anatomy and the common variations of this nerve. Therefore, the purpose of this study was to present an anatomical study of the external nasal nerve. Twenty external nasal nerves were examined by dissecting 10 fresh cadaver noses within 48 hours of death. On dissection, the exit of the nerve between the nasal bone and upper lateral cartilage was identified. The distance from the point of exit to the midline of the nose and the size of the nerve were measured. The course and the running plane of the nerve were investigated. The nerve branchings were also classified into three types: type I, only one nerve without any branch; type II, one nerve proximally and then splitting into two main branches at the intercartilaginous junction; and type III, two main branches from the point of exit. The point of exit of the external nasal nerve from the distal nasal bone was located 6.5 to 8.5 mm (7.3 +/- 0.6 mm) lateral to the nasal midline. The average diameter of the nerve at the point of exit was 0.35 +/- 0.036 mm. Most of the nerves (95 percent) passed through the deep fatty layer directly under the nasal superficial musculoaponeurotic layer, all the way down to the alar cartilages. In terms of the branching type, type I was observed in 10 of 20 nerves (50 percent), type II was observed in six of 20 (30 percent), and type III was seen in four of 20 (20 percent). On the basis of the results of this study, the following precautions are suggested during a rhinoplasty to minimize the chance of injury to this nerve. First, it is best to avoid deep intercartilaginous or intracartilaginous incisions so that the deep fatty layer is not invaded and the dissection is maintained directly on the surface of the cartilage (deep to the nasal superficial musculoaponeurotic layer). Second, dissection at the junction of the nasal bone and upper lateral cartilage area of one side should be limited to within 6.5 mm from the midline. Lastly, when the nasal dorsum is augmented by an onlay graft, implants or grafts less than 13 mm wide at the rhinion level should be used.

Oral insertion of a flexible bronchoscope is associated with less discomfort than nasal insertion for Korean patients

OBJECTIVE

The route of bronchoscope insertion varies between centres, without a firm rationale based on well-designed studies. We therefore compared nasal and oral insertion of a flexible bronchoscope and evaluated efficacy and patient satisfaction.

DESIGN

Prospective randomised study of patients who underwent flexible bronchoscopy from May to September 2003 and who were randomly assigned to nasal and oral insertion approaches.

RESULTS

Clinical characteristics, factors related to the procedure and patient satisfaction were analysed. In total, 307 patients were randomly assigned to the nasal (n = 158) or oral insertion groups (n = 149). No difference in baseline characteristics was identified between the groups. Insertion by the oral route was associated with a smaller amount of lidocaine use during the procedure (P = 0.04) and less frequent insertion site bleeding (P = 0.005). Patients assigned to oral insertion reported less discomfort during anaesthesia (P = 0.01) and scope insertion (P < 0.001), as well as less dyspnoea (P = 0.04) and coughing (P = 0.03).

CONCLUSION

Oral insertion of a flexible bronchoscope was associated with less discomfort for patients than nasal insertion, although the route of insertion had no significant effect on outcome.

Pilot-scale two-stage process: a combination of acidogenic hydrogenesis and methanogenesis

This study was performed to optimize both acidogenic hydrogenesis and methanogenesis, and then to develop a pilot-scale two-stage process producing not only CH4 but also H2. Firstly, acidogenic hydrogenesis of food waste was examined in pilot-scale leaching-bed reactors using dilution rate (D) as a tool to improve the environmental conditions. The maximum efficiency of 71.4% was obtained by adjusting D from 4.5 to 2.5 d(-1) depending on the state of degradation. Secondly, the wastewater from acidogenic hydrogenesis was converted to CH4 in a pilot-scale UASB reactor. The COD removal efficiency exceeded 95% up to the loading rates of 13.1 g COD/Ld, which corresponded to HRT of 0.25 d (6 h). Lastly, a pilot-scale two-stage process was devised based on a combination of acidogenic hydrogenesis and methanogenesis. Over 120 days, the pilot-scale process resulted in large VS reduction of 70.9% at the high loading rate of 12.5 kg VS/m3/d in a short SRT of 8 days.

Clinical Application of Fresh Fibroblast Allografts for the Treatment of Diabetic Foot Ulcers: A Pilot Study

Diabetic foot ulcers often pose a difficult problem for health care professionals because of the defects associated with fibroblast functioning. Although there has been much interest recently in the use of topical growth factors for the treatment of diabetic foot ulcers, the effects are generally not very dramatic. Cryopreserved fibroblast implants, which are able to adjust to a wound's environment and provide the desired growth factors and other substances that may be lacking in a chronic wound, represent an exciting development and a major advance. These products may well provide growth factors in the right concentration and in the right sequence, something that has proved difficult to achieve with the topical application of recombinant growth factors. However, cell activities are impaired by cryopreservation. The purpose of this study was to assess the effects of fresh human allogeneic fibroblast grafting for the treatment of diabetic foot ulcers. Eight patients with diabetic foot ulcers ranging from 6 to 17 weeks in duration were treated. The size of the wounds ranged from 2.0 to 6.0 cm2, with three patients exhibiting exposed bones. A history of diabetic foot ulcers was present in five patients. Human dermal fibroblasts from healthy teenagers were cultured in Dulbecco's modified Eagle medium/Ham's F-12 supplemented with 10% autologous serum. The cultured cells were applied over the wounds immediately after debridement; fibrin was used as a cell carrier. A dressing was then applied with Tegaderm and kept moist until healing was complete. The progress and time for complete wound closure and patient satisfaction were assessed, with follow-up time ranging from 6 to 18 months. Complete wound healing occurred in all patients. Eleven to 21 days were needed for complete reepithelization of the wound, and no clinical or laboratory abnormalities were noted. Patient satisfaction was also very positive. In this study, the use of fresh human fibroblast allografts was found to be a safe and effective treatment for diabetic foot ulcers.

Advantages of adding a footplate incision in Asian rhinoplasty

The dimension, shape, and projection of the nasal tip are significantly determined by the position of the footplates of the medial crura. The length of the footplate segment in Asians is much longer than that in Caucasians. A surgeon may be able to use a longer footplate segment when operating on an Asian to recreate the lower vault of the nose more effectively. The purpose of this study is to introduce the advantages of addition of a footplate incision to obtain greater satisfaction in esthetic rhinoplasty for Asians. This incision is extended along the caudal border of the footplate of the medial crura onto the floor of the nasal vestibule bilaterally, in endonasal or open approach rhinoplasty. By approximating the lateral curves of the medial crural footplates, the width and the length of the columella could be narrowed and lengthened. The columella can also be advanced caudally and thus elongate the shape of the nostrils. In addition, a cartilage graft or an implant insertion for alar base augmentation could be performed through this footplate incision, eliminating the need for an additional incision. Another advantage is that, during the correction of caudal septal deviation, displaced septal cartilage can be repositioned by suturing to the periosteum or soft tissue around the anterior nasal spine without drilling into it through an intraoral incision. One hundred ten consecutive patients who underwent esthetic rhinoplasty using our footplate incision technique between August of 1999 and May of 2002 were included in this study. A total of 66 patients had an adequate follow-up time of over 6 months. Patient satisfaction and postoperative complications were recorded. The majority of the patients (57/66 cases) were satisfied with the results of the procedure. The authors believe that the addition of the footplate incision in esthetic rhinoplasty is safe and reliable for effecting better results for Asians.

An anatomic study of nasal tip supporting structures

Successful rhinoplasty depends on nasal tip support and its influence on nasal tip projection. It is generally agreed that the components of nasal tip support include the attachment between the upper and lower lateral cartilages, the attachment between the lateral crus of the lower lateral cartilage and the pyriform aperture, the attachment between the paired domes of the lower lateral cartilages, and the medial crural attachment to the caudal septum. However, these structures are still not clearly determined, and there was no anatomic study of nasal tip supporting structures in Asia. The purpose of this study was to determine the nasal tip supporting structures and find out the differences in these structures between white and Asian people. Ten noses of fresh cadavers were investigated. Dissection was performed and the previously mentioned nasal tip supporting structures were observed and excised. Histologic examination was done with hematoxylin and eosin stain and Van Gieson elastin stain. Macroscopic study showed that there were dense fibrous tissue between the upper and lower lateral cartilages, dense fibrous tissue and sesamoid cartilages between the lateral crus and the pyriform aperture, loose connective tissue between the paired domes of lower lateral cartilages, and no identified specific tissue between the medial crus and the caudal septum. Microscopic investigation allowed a more detailed analysis of these structures. Between the upper and lower lateral cartilages, dense collagen fibers were running in one direction and anchoring firmly to each cartilage, which meets the histologic criteria of a ligament. Between the lateral crus and the pyriform aperture, there were intermingled collagen fibers and muscular fibers, which meets the histologic criteria of fibromuscular tissue. Between the paired domes of lower lateral cartilages, there were few fibers with abundant amorphous ground substances, which meets the histologic criteria of loose connective tissue. Based on our results, we recommend that the previously mentioned nasal tip supporting structures should be named intercartilaginous ligament, sesamoid fibromuscular tissue, and interdomal loose connective tissue, respectively. In addition, we consider that the loose connection between the domes of middle crura and the absence of an attachment of the medial crura to the caudal septum can be one of the reasons why the nasal tip of Asian people is broad and unprojected and the base is wide.

Response of pulmonary tuberculomas to anti-tuberculous treatment

Pulmonary tuberculomas are well-circumscribed masses caused by Mycobacterium tuberculosis. However, the response of tuberculomas to anti-tuberculous (TB) treatment has not been well defined as yet. The response of pulmonary tuberculomas to anti-TB treatment was retrospectively reviewed in 45 patients diagnosed between January 1997 and December 2001. The areas of pulmonary tuberculomas were estimated by calculating products of the longest and their perpendicular short diameters on chest radiographs. The response to anti-TB treatment was categorised as "decreased" (> 25% reduction in area versus its initial area), "increased" (> 251% increase) and "no change" (the remainder). The mean of treatment duration was 11.5 +/- 3.6 months. Three months after treatment, 18 patients (40.0%) were categorised as decreased, 25 (55.6%) as no change and two (4.4%) as increased. Twelve months after treatment, out of 42 patients available for chest radiographs, 32 patients (76.2%) were categorised as decreased, nine (21.4%) as no change and one patient (2.4%) as increased. At the last follow-up (mean follow-up 27.0 +/- 10.2 months), 37 patients (82.2%) were categorised as decreased. The majority of pulmonary tuberculomas were decreased by anti-tuberculosis treatment during and even after treatment, although a transient enlargement during the early period of treatment was observed infrequently.

Anaerobic co-digestion of sewage sludge and food waste using temperature-phased anaerobic digestion process

This study was performed to overcome the low efficiency of anaerobic digestion of sewage sludge and food waste by combining temperature-phased digestion, sequencing batch operation, and co-digestion technology. It was demonstrated that the temperature-phased anaerobic sequencing batch reactor (TPASBR) system for the co-digestion of sewage sludge and food waste resulted in enhanced volatile solids (VS) reduction and methane production rate. At the organic loading rate (OLR) of 2.7 g VS/l/d, the TPASBR system showed the higher VS reduction (61.3%), CH4 yield (0.28 l/g VS(added)) and CH4 production rate (0.41 l CH4/l/d) than those (0.29 l CH4/l/d) of the mesophilic two-stage ASBR (MTSASBR). In the specific methanogenic activity (SMA) tests on thermophilic biomass of the TPASBR system, the average SMA of acetate (93 ml CH4/gVSS/d) was much higher than those of propionate (46 ml CH4/g VSS/d) and butyrate (76 ml CH4/g VSS/d). Also, higher specific hydrolytic activity (SHA, 217 mg COD/g VSS/d) of the biomass supported fast hydrolysis under thermophilic conditions. The track study revealed that the most active period of the 24 h cycle was between 6 and 12 h. The enhanced performance of the TPASBR system could be attributed to longer solids retention time, fast hydrolysis, higher CH4 conversion rate, and balanced nutrient condition of co-substrate. It was verified that this combination could be a promising and practical alternative for the simultaneous recycling of two types of organic fraction of municipal solid waste (OFMSW) with high stability.

Advantages of the Presence of Living Dermal Fibroblasts Within Restylane for Soft Tissue Augmentation

For the elimination of facial wrinkles and skin contour defects, injectable filler substances composed of commercially prepared nonanimal stabilized hyaluronic acid (Restylane) are now widely used. Although this method of suspension has been shown to be relatively safe and convenient, varying degrees of resorption have required repeated percutaneous injections. This study was undertaken to evaluate the feasibility of Restylane, which is a modified hyaluronic acid, combined with cultured human dermal fibroblasts, to enhance the longevity of injected implants. The histologic changes of the injected implants were also evaluated. For the test group, fibroblasts from the dermis of healthy adults were isolated and cultivated. The cultured fibroblasts were measured with a hemocytometer. Five x 105 fibroblasts suspended in 200 microl of Dulbecco phosphate-buffered saline (DPBS) were then dispersed in 200 microl of Restylane to form a 400-microl human fibroblast-Restylane mix. For the control group, 200 microl of DPBS without fibroblasts were mixed with 200 microl of Restylane. These implants were subcutaneously injected into the back of an athymic nude mouse at 6 sites, the 3 left sites composing the control group and the 3 right sites composing the test group. Twelve nude mice were injected for a total of 36 injections per group. The nodular swellings that resulted from the injections were excised to include skin beyond the swelling points down to the panniculus carnosus layer using 5-mm punches, and the weights were measured at 1, 2, 4, 8, 12, and 16 weeks after the injections. Histologic comparisons were also performed to confirm the presence of human collagen in the fibroblast-mixed Restylane group using immunohistochemical study with antihuman collagen type I polyclonal antibody. The mean weight of the control group nodules decreased throughout the examination period. The mean weight at the 16th week was 60% of the weight at the first week. On the other hand, the mean weight of the test-group nodules decreased only over the first 2 weeks. Beyond 2 weeks, there was no further significant weight change. The mean weight at the 16th week was 91% of the weight measured at the first week. Histologic examinations of the control group exhibited negative immunohistochemical staining for human collagen at each examination period. The test group exhibited positive staining after 2 weeks, indicating the presence of human collagen. These results indicate that Restylane mixed with cultured human dermal fibroblasts may be successfully injected as living grafts for long-term retention of implants.

Lack of association between glutathione S-transferase P1 polymorphism and COPD in Koreans

The fact that only 10-20% of chronic heavy cigarette smokers develop symptomatic COPD and correlations of pulmonary function among twins and families suggests the presence of genetic susceptibility in the development of COPD. Genetic susceptibility to COPD might depend on the variations in enzyme activities that detoxify cigarette smoke products, such as microsomal epoxide hydrolase (mEPHX) and glutathione-S transferase (GST). The purpose of this study was to determine whether polymorphism of GSTP1 gene is linked to a genetic susceptibility to COPD. The hypothesis we tested here was that the polymorphism supposed to decrease GSTP1 activity would be the genetic risk for the development of COPD. Using PCR followed by restriction fragment length polymorphism (PCR-RFLP), genotypes of Ile105Val polymorphism in exon 5 of glutathione S-transferase P1 (GSTP1) gene were determined in 89 patients with COPD and 94 healthy smoking control subjects at the Seoul National University Hospital. Although the frequency of homozygous wild allele in exon 5 of GSTP1 gene in patients with COPD was higher than that observed in healthy controls (71% vs. 61%), the difference was not considered statistically significant. Neither the heterozygous nor homozygous mutant allele differed in frequency between the two groups. In conclusion, the genetic polymorphisms of exon 5 of GSTP1 gene may not be associated with development of COPD in Koreans.

The timing of neovascularization in fingertip replantation by external bleeding

To overcome venous congestion in fingertip replantation with no venous anastomosis, the authors have used a salvage procedure that consists of continuous external bleeding through a stab incision on the paraungual area and dripping a heparinized saline solution at the incision site to maintain external bleeding. Because this method requires continuous bleeding for a certain period of time, it may be a great burden on the patient; therefore, it is most important to minimize the duration of bleeding. Many authors have studied the timing of the new venous channel formation of the flap. However, to our knowledge, a study on fingertip replantations has not yet been performed. From June of 1985 to November of 1999, the authors performed fingertip replantations on 144 fingers of 137 patients using our salvage procedure at Korea University Guro Hospital. Among the 144 fingers, 101 fingers of 96 patients were successfully transplanted, including those with partial necrosis. The authors reviewed the medical records of these 101 fingers retrospectively; they compared and analyzed the necessary duration of external bleeding according to sex, age, level of injury, cause of amputation, and the type of injury. The average period of the salvage procedure was 7.6 days. Regarding age, the shortest period (5.5 days) was required for patients younger than 10 years. On the basis of the types of injuries, the duration of bleeding was shortest for the guillotine injury group (5.9 days) compared with crush (8.2 days) or avulsion (8.0 days) injuries. Sex and level of injury did not make much difference in the duration of the procedure.

Determination of the prognostic value of [(18)F]fluorodeoxyglucose uptake by using positron emission tomography in patients with non-small cell lung cancer

The aim of this study was to determine whether quantitative information obtained from [(18)F]fluorodeoxyglucose positron emission tomography ((18)F-FDG PET) has a prognostic significance for patients with non-small cell lung cancer (NSCLC). We investigated (18)F-FDG PET imaging of 73 patients with NSCLC. The maximum standardized uptake value (SUV(max)) was significantly different between the histopathological types of tumour (squamous cell carcinoma (n=37, 12.4+/-5.1), adenocarcinoma (n=30, 8.2+/-5.8), bronchioloalveolar carcinoma (n=4, 2.6+/-1.7), <0.01). In the univariate analysis of all patients, staging (P=0.0001), tumour cell type (P=0.013), and a SUV(max) greater than 7 (P=0.0011) was correlated with survival. However, a multivariate analysis identified staging and SUV(max) greater than 7 were affected survival adversely. The mortality rate of patients with group I disease (stage I to stage IIIA) was 5.8 times lower than that of patients with group II disease (stage IIIB to stage IV). Patients with a high SUV(max) (> or =7) had a 6.3 times higher mortality than those with a low SUV(max)(<7). By multivariate analysis of patients with squamous cell carcinoma, only grouping affected survival (P=0.008, relative risk=4.3). In the case of adenocarcinoma, the SUV(max) (>10) correlated exclusively with poorer survival (P=0.031, relative risk=11.152). (18)F-FDG uptake correlated with survival in NSCLC. Especially in adenocarcinomas, the SUV(max) was complementary to other known prognostic factors.

Noise-induced multimode behavior in excitable systems

Based on experiments with electronic circuits, we show how a system of coupled excitable units can possess several noise-induced oscillatory modes. We characterize the multimode organization in terms of the coherence resonance effect. Multiple gain of regularity is found to be related to different frequency entrainments and to the appearance of additional time scales.