Early identification of delayed wound healing in complex diabetic foot ulcers treated with a dermal regeneration template: a novel clinical target and its risk factors

BACKGROUND

The dermal regeneration template (DRT), a tissue-engineered skin substitute composing a permanent dermal matrix and an upper temporary silicone layer that serves as the epidermis, has demonstrated efficacy in treating uncomplicated diabetic foot ulcers (DFUs). Our institution has obtained good outcomes with DRT in patients with more complicated DFUs. Because of its chronicity, the authors are working to identify a clinical target that anticipates delayed healing early in the treatment in addition to determining the risk factors linked to this endpoint to increase prevention.

MATERIALS AND METHODS

This retrospective single-center study analyzed patients with DFUs who underwent wound reconstruction using DRT between 2016 and 2021. The patients were categorized into poor or good graft-take groups based on their DRT status on the 21st day after the application. Their relationship with complete healing (CH) rate at day 180 was analyzed. Variables were collected for risk factors for poor graft take at day 21. Independent risk factors were identified after multivariable analysis. The causes of poor graft take were also reported.

RESULTS

This study examined 80 patients (38 and 42 patients in the poor and good graft-take groups, respectively). On day 180, the CH rate was 86.3% overall, but the poor graft-take group had a significantly lower CH rate (76.3 vs. 95.2%, P =0.021) than the good graft-take group. Our analysis identified four independent risk factors: transcutaneous oxygen pressure less than 30 mmHg (odds ratio, 154.14), off-loading device usage (0.03), diabetic neuropathy (6.51), and toe wound (0.20). The most frequent cause of poor graft take was infection (44.7%), followed by vascular compromise (21.1%) and hematoma (15.8%).

CONCLUSION

Our study introduces the novel concept of poor graft take at day 21 associated with delayed wound healing. Four independent risk factors were identified, which allows physicians to arrange interventions to mitigate their effects or select patients more precisely. DRT represents a viable alternative to address DFUs, even in complicated wounds. A subsequent split-thickness skin graft is not always necessary to achieve CH.

Platelet-Derived Biomaterials Inhibit Nicotine-Induced Intervertebral Disc Degeneration Through Regulating IGF-1/AKT/IRS-1 Signaling Axis

Apart from aging process, adult intervertebral disc (IVD) undergoes various degenerative processes. However, the nicotine has not been well identified as a contributing etiology. According to a few studies, nicotine ingestion through smoking, air or clothing may significantly accumulate in active as well as passive smokers. Since nicotine has been demonstrated to adversely impact various physiological processes, such as sympathetic nervous system, leading to impaired vasculature and cellular apoptosis, we aimed to investigate whether nicotine could induce IVD degeneration. In particular, we evaluated dose-dependent impact of nicotine in vitro to simulate its chronic accumulation, which was later treated by platelet-derived biomaterials (PDB). Further, during in vivo studies, mice were subcutaneously administered with nicotine to examine IVD-associated pathologic changes. The results revealed that nicotine could significantly reduce chondrocytes and chondrogenic indicators (Sox, Col II and aggrecan). Mice with nicotine treatment also exhibited malformed IVD structure with decreased Col II as well as proteoglycans, which was significantly increased after PDB administration for 4 weeks. Mechanistically, PDB significantly restored the levels of IGF-1 signaling proteins, particularly pIGF-1 R, pAKT, and IRS-1, modulating ECM synthesis by chondrocytes. Conclusively, the PDB impart reparative and tissue regenerative processes by inhibiting nicotine-initiated IVD degeneration, through regulating IGF-1/AKT/IRS-1 signaling axis.

Amelioration of Nicotine-Induced Osteoarthritis by Platelet-Derived Biomaterials Through Modulating IGF-1/AKT/IRS-1 Signaling Axis

Besides inhalation, a few studies have indicated that the uptake of nicotine through air or clothing may be a significant pathway of its exposure among passive smokers. Nicotine is well known to exert various physiological impacts, including stimulating sympathetic nervous system, causing vascular disturbances, and inducing cell death. Therefore, we aimed to establish whether exposure of nicotine could induce articular cartilage degeneration in a mouse model of osteoarthritis (OA). We specifically assessed dose-dependent effect of nicotine in vitro to mimic its accumulation. Further, during the in vivo studies, mice subcutaneously administered with nicotine was examined for OA-associated pathologic changes. We found that nicotine significantly suppressed chondrocytes and chondrogenic markers (Sox, Col II, and aggrecan). Nicotine-treated mice also showed altered knee joint ultrastructure with reduced Col II and proteoglycans. After corroborating nicotine-induced OA characteristics, we treated this pathologic condition through employing platelet-derived biomaterial (PDB)-based regenerative therapy. The PDB significantly suppressed OA-like pathophysiological characteristics by 4 weeks. The mechanistic insight underlying this therapy demonstrated that PDB significantly restored levels of insulin-like growth factor 1 (IGF-1) signaling pathway proteins, especially pIGF-1 R, pAKT, and IRS-1, regulating extracellular matrix synthesis by chondrocytes. Taken together, the PDB exerts regenerative and reparative activities in nicotine-mediated initiation and progression of OA, through modulating IGF-1/AKT/IRS-1 signaling axis.

Adipose-derived Stem Cells Attenuates Diabetic Osteoarthritis via Inhibition of Glycation-mediated Inflammatory Cascade

Diabetes mellitus (DM) is well-known to exert complications such as retinopathy, cardiomyopathy and neuropathy. However, in recent years, an elevated osteoarthritis (OA) complaints among diabetics have been observed, portending the risk of diabetic OA. Since formation of advanced glycation end products (AGE) is believed to be the etiology of various diseases under hyperglycemic conditions, we firstly established that streptozotocin-induced DM could potentiate the development of OA in C57BL/6J mouse model, and further explored the intra-articularly administered adipose-derived stem cell (ADSC) therapy focusing on underlying AGE-associated mechanism. Our results demonstrated that hyperglycemic mice exhibited OA-like structural impairments including a proteoglycan loss and articular cartilage fibrillations in knee joint. Highly expressed levels of carboxymethyl lysine (CML), an AGE and their receptors (RAGE), which are hallmarks of hyperglycemic microenvironment were manifested. The elevated oxidative stress in diabetic OA knee-joint was revealed through increased levels of malondialdehyde (MDA). Further, oxidative stress-activated nuclear factor kappa B (NF-κB), the marker of proinflammatory signalling pathway was also accrued; and levels of matrix metalloproteinase-1 and 13 were upregulated. However, ADSC treatment attenuated all OA-like changes by 4 weeks, and dampened levels of CML, RAGE, MDA, NF-κB, MMP-1 and 13. These results suggest that during repair and regeneration, ADSCs inhibited glycation-mediated inflammatory cascade and rejuvenated cartilaginous tissue, thereby promoting knee-joint integrity in diabetic milieu.

Mechanistic insight into hyaluronic acid and platelet-rich plasma-mediated anti-inflammatory and anti-apoptotic activities in osteoarthritic mice

Osteoarthritis (OA) poses a major clinical challenges owing to limited regenerative ability of diseased or traumatized chondrocytes in articular cartilage. Previous studies have determined the individual therapeutic efficacies of hyaluronic acid (HA) and platelet-rich plasma (PRP) on OA; however, the underlying mechanism is still lacking. Therefore, we investigated mechanistic approach of HA+PRP therapy on chondrocyte apoptosis in IL-1β+TNF-α (I+T) treated in vitro OA model, in addition to in vivo anterior cruciate ligament transection-OA mice model. MTT assay showed an enhanced chondrocyte proliferation and viability in HA+PRP-treated group, compared to I+T, I+T/HA, I+T/PRP, I+T/HA+PRP groups. Further, HA+PRP also significantly suppressed ROS, apoptotic cleaved caspase-3 and PARP, p53 and p21 and MMP-1; whereas, cell cycle modulatory proteins including p-ERK, cyclin B1, D1, and E2 were upregulated. The sub-G1 population and TUNEL assay confirmed the higher abundance of healthy chondrocytes in HA+PRP group. A significantly decreased ARS staining in HA+PRP group was also noted, indicating reduced cartilaginous matrix mineralization compared to other groups. Conclusively, compared to HA or PRP, the combined HA+PRP might be a promising therapy for articular cartilage regeneration in osteoarthritic pathology, possibly via augmented anti-inflammatory, anti-oxidative chondrocyte proliferation and inhibited MMP-1 activity and matrix calcification.

Revisiting the Advances in Isolation, Characterization and Secretome of Adipose-Derived Stromal/Stem Cells

Adipose-derived stromal/stem cells (ASCs) seems to be a promising regenerative therapeutic agent due to the minimally invasive approach of their harvest and multi-lineage differentiation potential. The harvested adipose tissues are further digested to extract stromal vascular fraction (SVF), which is cultured, and the anchorage-dependent cells are isolated in order to characterize their stemness, surface markers, and multi-differentiation potential. The differentiation potential of ASCs is directed through manipulating culture medium composition with an introduction of growth factors to obtain the desired cell type. ASCs have been widely studied for its regenerative therapeutic solution to neurologic, skin, wound, muscle, bone, and other disorders. These therapeutic outcomes of ASCs are achieved possibly via autocrine and paracrine effects of their secretome comprising of cytokines, extracellular proteins and RNAs. Therefore, secretome-derivatives might offer huge advantages over cells through their synthesis and storage for long-term use. When considering the therapeutic significance and future prospects of ASCs, this review summarizes the recent developments made in harvesting, isolation, and characterization. Furthermore, this article also provides a deeper insight into secretome of ASCs mediating regenerative efficacy.

Addressing Stem Cell Therapeutic Approaches in Pathobiology of Diabetes and Its Complications

High morbidity and mortality of diabetes mellitus (DM) throughout the human population is a serious threat which needs to be addressed cautiously. Type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM) are most prevalent forms. Disruption in insulin regulation and resistance leads to increased formation and accumulation of advanced end products (AGEs), which further enhance oxidative and nitrosative stress leading to microvascular (retinopathy, neuropathy, and nephropathy) and macrovascular complications. These complications affect the normal function of organ and tissues and may cause life-threatening disorders, if hyperglycemia persists and improperly controlled. Current and traditional treatment procedures are only focused on to regulate the insulin level and do not cure the diabetic complications. Pancreatic transplantation seemed a viable alternative; however, it is limited due to lack of donors. Cell-based therapy such as stem cells is considered as a promising therapeutic agent against DM and diabetic complications owing to their multilineage differentiation and regeneration potential. Previous studies have demonstrated the various impacts of both pluripotent and multipotent stem cells on DM and its micro- and macrovascular complications. Therefore, this review summarizes the potential of stem cells to treat DM and its related complications.

Safety and efficacy of endoscopic spray cryotherapy for esophageal cancer

Although surgery is traditionally the standard of care for esophageal cancer, esophagectomy carries significant morbidity. Alternative endoscopic therapies are needed for patients who are not candidates for conventional treatment. The objective of this study is to assess the safety, efficacy, and tolerability of spray cryotherapy of esophageal adenocarcinoma. This study includes patients with esophageal adenocarcinoma who had failed or were not candidates for conventional therapy enrolled retrospectively and prospectively in an open-label registry and patients in a retrospective cohort from 11 academic and community practices. Endoscopic spray cryotherapy was performed until biopsy proven local tumor eradication or until treatment was halted due to progression of disease, patient withdrawal or comorbidities. Eighty-eight patients with esophageal adenocarcinoma (median age 76, 80.7% male, mean length 5.1 cm) underwent 359 treatments (mean 4.4 per patient). Tumor stages included 39 with T1a, 25 with T1b, 9 with unspecified T1, and 15 with T2. Eighty-six patients completed treatment with complete response of intraluminal disease in 55.8%, including complete response in 76.3% for T1a, 45.8% for T1b, 66.2% for all T1, and 6.7% for T2. Mean follow-up was 18.4 months. There were no deaths or perforations related to spray cryotherapy. Strictures developed in 12 of 88 patients (13.6%) but were present before spray cryotherapy in 3 of 12. This study suggests that endoscopic spray cryotherapy is a safe, well-tolerated, and effective treatment option for early esophageal adenocarcinoma.

Non-invasive in vivo molecular imaging of intra-articularly transplanted immortalized bone marrow stem cells for osteoarthritis treatment

Pathophysiology of osteoarthritis (OA) is characterized by progressive loss of articular cartilage in the knee-joints. To impart regenerative ability in lowly metabolizing chondrocytes, the bone marrow stem cells (BMSCs) has recently been recognized as a superior alternative treatment for OA. However, study of primary BMSCs-mediated chondrogenesis is difficult due to progressive cellular aging and replicative senescence. To obtain a therapeutic cell population for OA, BMSCs were immortalized by human papilloma virus (HPV)-16 E6/E7 along with mCherry luciferase (mCL), a gene marker for non-invasive imaging, and designated as iBMSCs-mCL. Next, their cell morphology, population doubling time (PDT) and colony forming ability (CFU) were evaluated. Furthermore, pluripotency and immunophenotypic markers were investigated. To deduce therapeutic ability, iBMSCs-mCL were intra-articularly injected into right knee of anterior cruciate ligament transaction (ACLT)-OA mice model and tracked through non-invasive bioluminescence imaging. Cell morphology of iBMSCs-mCL was similar to parental BMSCs. PDT and CFU ability of iBMSCs-mCLs were significantly increased. Pluripotency and immunophenotypic markers were highly expressed in iBMSC-mCL. Long-term survival and tri-lineage differentiation particularly chondrogenic potential of iBMSCs-mCL were also demonstrated in vitro and then in vivo which was monitored through non-invasive imaging. Intensive bioluminescent signals in iBMSCs-mCL administered knee-joint indicated a marked in vivo survival and proliferation of iBMSCs-mCL. Immunohistochemical staining for type II collagen (IHC of Col II) and alcian blue & safranin o staining of proteoglycans also corroborated cartilage regeneration by iBMSCs-mCL. Conclusively, iBMSCs-mCL maintains stemness and in vivo cartilage regeneration potential suggesting a promising avenue for development of OA therapeutics.

Cordyceps militaris Treatment Preserves Renal Function in Type 2 Diabetic Nephropathy Mice

Diabetic nephropathy is derived from long-term effects of high blood glucose on kidney function in type 2 diabetic patients. Several antidiabetic drugs and herbal medications have failed to prevent episodes of DN. Hence, this study aimed to further investigate the renal injury-reducing effect of antidiabetic CmNo1, a novel combination of powders of fruiting bodies and mycelia of Cordyceps militaris. After being administered with streptozotocin-nicotinamide and high-fat-diet, the diabetic nephropathy mouse model displayed elevated blood glucose and renal dysfunction markers including serum creatinine and kidney-to-body weight ratio. These elevated markers were significantly mitigated following 8 weeks CmNo1 treatment. Moreover, the chronic hyperglycemia-induced pathological alteration in renal tissue were also ameliorated. Besides, immunohistochemical study demonstrated a substantial reduction in elevated levels of carboxymethyl lysine, an advanced glycation end product. Elevated collagenous deposition in DN group was also attenuated through CmNo1 administration. Moreover, the enhanced levels of transforming growth factor-β1, a fibrosis-inducing protein in glomerulus were also markedly dampened. Furthermore, auxiliary risk factors in DN like serum triglycerides and cholesterol were found to be increased but were decreased by CmNo1 treatment. Conclusively, the results suggests that CmNo1 exhibit potent and efficacious renoprotective action against hyperglycemia-induced DN.

Safety and efficacy of endoscopic spray cryotherapy for Barrett's dysplasia: results of the National Cryospray Registry

Retrospective series have shown the efficacy of endoscopic spray cryotherapy in eradicating high-grade dysplasia (HGD) in Barrett's esophagus (BE); however, prospective data are lacking, and efficacy for low-grade dysplasia (LGD) is unclear. The aim of this study was to assess the efficacy and safety of spray cryotherapy in patients with LGD or HGD. A multicenter, prospective open-label registry enrolled patients with dysplastic BE. Spray cryotherapy was performed every 2-3 months until there was no endoscopic evidence of BE and no histological evidence of dysplasia, followed by surveillance endoscopies up to 2 years. Primary outcome measures were complete eradication of dysplasia (CE-D) and complete eradication of all intestinal metaplasia (CE-IM). Ninety-six subjects with Barrett's dysplasia (67% HGD; 65% long-segment BE; mean length 4.5 cm) underwent 321 treatments (mean 3.3 per subject). Mean age was 67 years, 83% were male. Eighty patients (83%) completed treatment with follow-up endoscopy (mean duration 21 months). In patients with LGD, rate of CE-D was 91% (21/23) and rate of CE-IM was 61% (14/23). In HGD, CE-D rate was 81% (46/57) and CE-IM was 65% (37/57). In patients with short-segment BE (SSBE) with any dysplasia, CE-D was achieved in 97% (30/31) and CE-IM in 77% (24/31). There were no esophageal perforations or related deaths. One subject developed a stricture, which did not require dilation. One patient was hospitalized for bleeding in the setting of non-steroidal anti-inflammatory drug use. In the largest prospective cohort to date, data suggest endoscopic spray cryotherapy is a safe and effective modality for eradication of BE with LGD or HGD, particularly with SSBE.

Subsequent ischemic events associated with lower extremity amputations in patients with type 2 diabetes: a population-based cohort study

AIMS

To explore the risk of subsequent ischemic events in type 2 diabetes mellitus (DM) patients who had lower extremity amputations (LEAs) were compared with DM patients without LEAs.

METHODS

A population-based cohort study was conducted utilizing the data of 2011 patients with newly diagnosed DM with and without LEAs sourced from the Longitudinal Health Insurance Database 2000 (LHID 2000) of the Taiwan National Health Insurance (NHI) program between 1996 and 2008.

MAIN OUTCOME MEASURES

Relative risks (RRs), hazard ratios (HRs), and disease-free rates for various ischemic events.

RESULTS

In contrast with the comparison group, subjects with LEAs were more likely to reside in less urbanized areas, be white collar workers, and have higher DM-related costs (p<0.05). Subjects with LEAs also had significantly higher risks of developing ischemic diseases, except intestinal ischemia. In the multivariate Cox proportional hazards regression model analysis, the HR of end-stage renal disease (ESRD) was highest (HR=3.91, 95% CI=2.38-6.42), followed by embolism and thrombosis (HR=3.47, 95% CI=2.12-5.67), other peripheral vascular diseases (HR=3.11, 95% CI=2.11-4.57), atherosclerosis (HR=2.64, 95% CI=1.60-4.35), retinopathy (HR=2.24, 95% CI=1.79-2.80), cerebral ischemia (HR=1.61, 95% CI=1.25-2.06), and coronary artery disease (HR=1.44, 95% CI=1.18-1.74).

CONCLUSIONS

DM patients with LEAs had significantly higher risks for subsequent ischemic events, particularly among men. The greatest risk detected among DM patients with LEA's was for end-stage renal disease. Disease free survival rates also indicated that the course of generalized DM ischemia proceeded despite treatment.

Combined treatment with regulatory T cells and vascularized bone marrow transplantation creates mixed chimerism and induces donor-specific tolerance to vascularized composite allografts without cytoreductive conditioning

We demonstrate herein that combination treatment with regulatory T cells (Tregs) and vascularized bone marrow transplantation (VBMT) can achieve stable mixed chimerism and long-term transplantation tolerance to vascularized composite allografts (VCA) without requiring cytoreductive recipient conditioning in rats. An appreciable number of Tregs of recipient origin was shown at the interface between recipient and transplanted VCA tissues, implicating a significant role for Tregs in protecting VCA from rejection. This cytoreduction-free protocol using co-treatment with Tregs and VBMT warrants further investigation toward potential clinical application for VCA transplantation.

Damage from periorbital ageing to the multilayered structures and resilience of the skin in Chinese population

Ageing dynamically disrupts the multilayered supporting components of the skin that are held together by cell adhesion molecules (CAMs). Skin specimens from 33 female Chinese patients undergoing lower blepharoplasty were divided into three age groups and examined by haematoxylin and eosin (H&E) staining, immunohistochemistry (IHC) and Elastica-van Gieson (EVG) stains, western blotting, surface electron microscopy (SEM) and biomechanical tension analysis. The SEM density (skin surface topology) showed a negative linear relationship with age. The triangular pattern of the skin surface in the younger group gradually broke down into quadrangular and irregular patterns in the older group. Collagens and elastic fibres in the dermis showed anisotropy and decreased density in the older groups compared with the younger group, especially in the papillary dermis. Anisotropy means that physical properties differ according to the direction of measurement. E-cadherin and integrin αv (whose functions are to bind epidermal and dermal elements respectively) increased and decreased, respectively, in the oldest group. Skin resilience decreased significantly in this group under repetitive stress. In conclusion, a loss of skin surface textures, integrin αv expressions, epidermal-dermal connections and dermal compactness led to the multilayered structure of the skin becoming separated. This in turn decreased resilience during ageing. These findings may therefore explain why aged skins cannot tolerate repetitive facial expressions, and why this action produces further dynamic wrinkles.

Spatiotemporal dynamics of the biological interface between cancer and the microenvironment: a fractal anomalous diffusion model with microenvironment plasticity

BACKGROUND

The invasion-metastasis cascade of cancer involves a process of parallel progression. A biological interface (module) in which cells is linked with ECM (extracellular matrix) by CAMs (cell adhesion molecules) has been proposed as a tool for tracing cancer spatiotemporal dynamics.

METHODS

A mathematical model was established to simulate cancer cell migration. Human uterine leiomyoma specimens, in vitro cell migration assay, quantitative real-time PCR, western blotting, dynamic viscosity, and an in vivo C57BL6 mouse model were used to verify the predictive findings of our model.

RESULTS

The return to origin probability (RTOP) and its related CAM expression ratio in tumors, so-called "tumor self-seeding", gradually decreased with increased tumor size, and approached the 3D Pólya random walk constant (0.340537) in a periodic structure. The biphasic pattern of cancer cell migration revealed that cancer cells initially grew together and subsequently began spreading. A higher viscosity of fillers applied to the cancer surface was associated with a significantly greater inhibitory effect on cancer migration, in accordance with the Stokes-Einstein equation.

CONCLUSION

The positional probability and cell-CAM-ECM interface (module) in the fractal framework helped us decipher cancer spatiotemporal dynamics; in addition we modeled the methods of cancer control by manipulating the microenvironment plasticity or inhibiting the CAM expression to the Pólya random walk, Pólya constant.

Taiwanofungus camphoratus (Syn Antrodia camphorata) extract and amphotericin B exert adjuvant effects via mitochondrial apoptotic pathway

The use of multiple drugs in cancer therapy increases the efficacy of the potential therapeutic effects. In this study, the authors investigated the adjuvant effects of an ethanol extract of solid-state cultivated Taiwanofungus camphoratus (TCEE) and amphotericin B (AmB) in the human cancer cell lines RPMI7951 and MG63. Taiwanofungus camphoratus is a well-known Chinese medicine in Taiwan, and AmB is a widely used antifungal agent. The authors demonstrated that TCEE pretreatment followed by AmB treatment effectively inhibited cell growth. The combination of sublethal doses of TCEE and AmB revealed a significant growth inhibitory effect in both cell lines. The combination of TCEE and AmB but not AmB alone induced phosphatidylserine externalization and loss of mitochondrial membrane potential. Cell cycle analyses revealed that combination of TCEE and AmB triggered G2/M arrest and significant apoptosis after 48 hours. These effects were greater than those achieved using TCEE or AmB alone. Furthermore, the authors demonstrated that the drugs increased the levels of p21(Cip1/Waf1) and pro-apoptotic protein Bax and reduced the level of anti-apoptotic protein Bcl-2. Taken together, the results showed that the combination treatment of TCEE and AmB displays strong adjuvant effects, which are indicated by the inhibition of cell proliferation in 2 human cancer cell lines, RPMI7951 and MG63. These findings suggest possible therapeutic applications and alternative medicines using this drug combination.

YC-1, a potent antithrombotic agent, induces lipolysis through the PKA pathway in rat visceral fat cells

This study investigated the effects of 3-(5'-hydroxymethyl-2'-furyl)-1-benzylindazole (YC-1), a soluble guanylyl cyclase (sGC) activator and potential antithrombotic agent, on lipolysis in isolated visceral fat cells of the rat. Visceral fat cells were isolated from epididymal fat pads of rats and treated with YC-1 at different doses and times. Glycerol release, and intracellular cAMP and cGMP levels were analyzed by specific kits. Moreover, several inhibitors or drugs were used to examine the signal transduction pathways of YC-1-induced lipolysis in adipocytes. Herein we report that YC-1 stimulated glycerol release in dose- and time-dependent manners. Intracellular cAMP and cGMP levels of adipocytes both increased in time-dependent manners, but elevation of the cGMP level was faster and higher than that of the cAMP level after YC-1 treatment. An sGC inhibitor (ODQ) inhibited YC-1-induced glycerol release, indicating the involvement of sGC in YC-1-induced lipolysis. Administration of insulin, an activator of type-3B phosphodiesterase (PDE-3B), attenuated YC-1-induced lipolysis, indicating that elevation of the cAMP level is an important step in the lipolytic effect of YC-1. In addition, YC-1-induced lipolysis was inhibited by a protein kinase A (PKA) inhibitor (KT5720) but not by a PKG inhibitor (KT5823), indicating that YC-1-induced lipolysis occurs through a PKA-dependent pathway. A Western blot analysis showed that extracellular signal-regulated kinase was not phosphorylated by YC-1 treatment. In conclusion, our results suggest that YC-1 might stimulate lipolysis via activation of sGC/cGMP and then activation of the cAMP/PKA signaling cascade in isolated rat visceral adipocytes.

Optimizing chimerism level through bone marrow transplantation and irradiation to induce long-term tolerance to composite tissue allotransplantation

BACKGROUND

Mixed chimerism with long-term composite tissue allotransplant (CTA) acceptance can be achieved through allogeneic bone marrow transplantation (BMT). The present study investigated the optimal chimerism level by giving different irradiation dosages to recipients to induce tolerance to CTA.

METHODS

Chimera were prepared using Brown-Norway and Lewis rats with strong major histocompatibility complex incompatibility. The Lewis rats received 5 mg antilymphocyte globulin (day -1 and 10) and 16 mg/kg cyclosporine (day 0-10) and were separated into groups 1, 2, 3, 4, and 5 according to the day -1 irradiation dosage: 0, 200, 400, 600, and 950 cGy, respectively. The Lewis rats were then reconstituted with 100 × 10(6) T-cell-depleted Brown-Norway bone marrow cells (day 0) and received vascularized Brown-Norway-CTA on day 28. Chimerism was assessed monthly by flow cytometry starting on day 28 after BMT. Graft-versus-host disease (GVHD) was assessed clinically and histologically.

RESULTS

Chimerism, 4 weeks after BMT, averaged 0.2%, 9.2%, 30.7%, 58%, and 99.3% in groups 1 to 5, respectively. GVHD occurred as follows: groups 1 and 2, none; group 3, 1 case of GVHD; group 4, 7 cases of GVHD (of which 3 died); and group 5, 10 cases of GVHD (of which 6 died). The percentage of long-term CTA acceptance was 0%, 0%, 90%, 70%, and 40% in groups 1 to 5, respectively. The percentage of regulatory T cells was significantly lower in high-chimerism (≥ 20%, n = 15) than in low-chimerism (<20%, n = 5) rats that accepted CTA long-term .

CONCLUSIONS

The chimerism level correlated positively with GVHD occurrence and long-term CTA acceptance but correlated negatively with regulatory T-cell levels. Optimal chimerism for CTA acceptance through pre-CTA BMT and irradiation occurs at 20-50% at day 28 after BMT in the rat model.

Analysis of medical litigation among patients with medical disputes in cosmetic surgery in Taiwan

BACKGROUND

This study aimed to investigate the key factors in medical disputes (arguments) among female patients after cosmetic surgery in Taiwan and to explore the correlates of medical litigation.

METHODS

A total of 6,888 patients (3,210 patients from two hospitals and 3,678 patients from two clinics) received cosmetic surgery from January 2001 to December 2009. The inclusion criteria specified female patients with a medical dispute. Chi-square testing and multiple logistic regression analysis were used to analyze the data.

RESULTS

Of the 43 patients who had a medical dispute (hospitals, 0.53%; clinics, 0.73%), 9 plaintiffs eventually filed suit against their plastic surgeons. Such an outcome exhibited a decreasing annual trend. The hospitals and clinics did not differ significantly in terms of patient profiles. The Chi-square test showed that most patients with a medical dispute (p < 0.05) were older than 30 years, were divorced or married, had received operations under general anesthesia, had no economic stress, had a history of medical litigation, and eventually did not sue the surgeons. The test results also showed that the surgeon's seniority and experience significantly influenced the possibility of medical dispute and nonlitigation. Multiple logistical regression analysis further showed that the patients who did decide to enter into litigation had two main related factors: marital stress (odds ratio [OR], 10.67; 95% confidence interval [CI], 1.20-94.73) and an education level below junior college (OR, 9.33; 95% CI, 1.01-86.36).

CONCLUSION

The study findings suggest that the key characteristics of patients and surgeons should be taken into consideration not only in the search for ways to enhance pre- and postoperative communication but also as useful information for expert testimony in the inquisitorial law system.

A multidisciplinary diabetic foot ulcer treatment programme significantly improved the outcome in patients with infected diabetic foot ulcers

BACKGROUND

Diabetic foot ulcers (DFUs) superimposed by infection and ischaemia may result in amputation without prompt and adequate management. We investigated whether the diabetic foot ulcer treatment programme (DFUTP) involving immediate debridement within 12 h, flap coverage and/or revascularisation improved the outcome of patients with infected DFUs.

METHOD

Between 2006 and 2009, we randomly enrolled 350 patients in the DFUTP group and compared them with control patients (the non-DFUTP group, n = 386) in Taiwan. Inclusion criteria consisted of infected diabetic foot ulcers with or without ischaemia. The risk factors, dynamics and outcome of amputation and re-amputation were analysed in terms of patient demographics, glycaemic control and infection.

RESULT

The results of logistic regression analyses indicated that risk factors of amputation in both groups were HbA1c (odds ratio (OR) = 1.63, 95% confidence interval (CI) 1.31-2.02) and C reactive protein (OR = 1.12, 95% CI 1.01-1.24). The DFUTP group showed a lower amputation rate than the non-DFUTP group (p = 0.001). The association between the amputation and University of Texas (UT) classification was not statistically significant. The Kaplan-Meier estimate showed that the time to complete recovery of the sugar level in the DFUTP group was faster than in the non-DFUTP group (p = 0.001). For patients at stage D, the hospital stay in the non-DFUTP group was longer than in the DFUTP group (p = 0.014).

CONCLUSION

The DFUTP provides an effective treatment programme for decreasing the amputation rate with infected DFUs. Immediate debridement and flap reconstruction decrease the amputation and re-amputation rate respectively.

Denervation dynamically regulates integrin alpha7 signaling pathways and microscopic structures in rats

BACKGROUND

Peripheral nerve injury causes serious problems in orthopedic and plastic surgeries. Cell adhesion molecules such as integrin alpha7 provoke cell binding and signaling pathways within myofibers. Expression profiles of integrin alpha7 signaling pathways and the molecule's microscopic structure were assessed to investigate the long-term dynamic changes in denervated rat skeletal muscle.

METHODS

A denervated rat skeletal muscle model was established by severing the sciatic nerve for 1 week, 2 weeks, 4 weeks, 8 weeks, 12 weeks, 20 weeks, and 26 weeks. Molecular expressions were investigated by mRNA and Western blot. The structural alterations were detected by immunohistochemistry, scanning electron microscopy, and transmission electron microscopy.

RESULTS

The denervated muscle atrophy presented the following dynamic molecular alterations: an initial increase around postdenervation in week (PIW) 8 and then a subsequent decay of integrin alpha7, integrin downstream signaling pathway (Ras or Raf or, ERK1/2), Akt, cleaved caspase-3, fast myosin heavy chain (MHC), beta actin, and RhoA. We demonstrated that the expressions of multiple signaling molecules were highly upregulated at PIW 8 (p<0.01). Scanning electron microscopy findings of the surface textures of myofibers showed more severe damage at PIW 8 and subsequently became smoother. Inner structures of myofibers separated with discontinuity on transmission electron microscopy examinations.

CONCLUSION

Our novel finding showed that time-series alterations of integrin alpha7 signaling molecules and surface microstructures in the long-term denervated rat skeletal muscle are biphasic and coherently dynamic. Persisted p-Akt elevation suggested that denervated muscle may regenerate if reinnervation or other treatment was performed.

Downregulation of the integrin α(v) signaling pathway in uterine leiomyomas

OBJECTIVE

To investigate alterations of integrin α(v), survival and apoptosis signaling pathways in uterine leiomyomas.

MATERIALS AND METHODS

In a prospective study of 50 women with uterine leiomyomas that had been pathologically confirmed, specimens were obtained laparoscopically from 2007 to 2009. The expressions of integrin α(v) signaling pathways (Ras/Raf/ERK1/2, Akt and cleaved caspase-3), surface microstructures by surface electron microscopy and immunohistochemical findings were assessed.

RESULTS

The study yielded novel results: (1) the integrin α(v) expression approached a low level (mRNA 0.39 ± 0.06, protein 0.47 ± 0.08) with coherent alterations of its downstream signaling molecules (Ras, p-c-Raf, p-ERK1/2) (p < 0.001); (2) smoother surface microstructures of uterine leiomyomas were correlated with low integrin α(v) expressions, and (3) survival signaling and apoptosis signaling were significantly down- and upregulated respectively (p < 0.001).

CONCLUSION

Integrin α(v) and related survival signaling pathways were downregulated, but the apoptosis was upregulated in uterine leiomyomas. Benign smooth-contoured tumors may have low integrin expressions and cancer invasion potentials.

Comparison between neurectomy and botulinum toxin A injection for denervated skeletal muscle

Neurectomy and botulinum toxin A (BoNT-A) injection cause denervated muscle atrophy, but questions remain about their clinical utility. We investigated time-series alterations of rat muscle weight, functional deficits, signaling pathways, and microscopic structures, to gain an understanding of the clinical implications. Between 2008 and 2009, the maximal calf circumference of patients for calf reduction either by neurectomy or BoNT-A injections were recorded for study. A rat skeletal muscle model was established through repeated or dose-adjusted BoNT-A injections and neurectomy. The survival, apoptosis pathways, functional deficits, and microscopic structures were investigated using Western blot, sciatic functional index (SFI), and transmission electron microscopy (TEM), respectively. The rat muscle weight ratio of the BoNT-A group had recovered to 89.3 +/- 3.8% by week 58, but it never recovered in the neurectomy group. Muscle weight reduction by BoNT-A not only depended on the dose, but additive effects were also obtained through repeated injections. Rat SFI demonstrated rapid recovery in both groups. Molecular expressions showed a coherent and biphasic pattern. p-Akt and apoptosis-inducing factor (AIF) were upregulated significantly, with a peak at 8 weeks in the neurectomy group (p < 0.01), but cleaved caspase-9 and caspase-3 showed no significant changes in either group. TEM findings showed irreversible and reversible inner-structure disruption and sarcomere discontinuity in the neurectomy and BoNT-A groups, respectively. We demonstrated that denervation induced lasting muscle weight and structural changes of different degrees. Muscle weight reduction by BoNT-A was related to frequency and dose. AIF-mediated caspase-independent apoptosis was significantly different for neurectomy and BoNT-A injection.

Correction of asymmetric calf hypertrophy with differential selective neurectomy

Contour asymmetry of the legs is a major aesthetic concern among Asian women. This study enrolled 60 patients with asymmetric calf hypertrophy, defined as a differential calf circumference exceeding 0.6 cm. Differential selective neurectomy techniques, which depend on the sizes of the small and large calves, were performed exactly via a 1-cm popliteal wound. The pre- and postoperative mean differences between the larger and smaller calf circumferences at the 1-year follow-up consultation were 1.38 +/- 0.65 and 0.42 +/- 0.38 cm, respectively (p < 0.01). The reduction was significantly greater in the leg that was initially larger. The procedure was effective in reducing circumference discrepancies so that leg contours were more balanced. All the patients were able to ambulate normally within 5 months after the procedure without disability. The authors posit that differential neurectomy is a safe and reliable technique for the correction of asymmetric calf hypertrophy, with minimal morbidities.

The classification and treatment algorithm for post-burn cervical contractures reconstructed with free flaps

Neck contractures after burn produce restrictions in motion and unacceptable aesthetic outcomes. Proper planning and tissue selection is essential to minimize donor site morbidity while optimizing outcomes. A classification system and treatment algorithm aids in achieving this goal. Between December 1999 and January 2003, 40 burn patients underwent release and reconstruction with free perforator flaps. Neck extensibility and zone of injury were evaluated. Choice of reconstruction was based on available tissue, restriction degree and zones involved. Cervical territories were classified according to movement restrictions and amount of improvement. Reconstructive territories were classified as central above (CA), central below (CB), central above and below (CAB) and lateral (L). Single, split, double and preexpanded free flaps were used for the reconstructions. Maximal gain in motion was noted at 4 weeks and maintained for the average 11 months follow-up. Types of reconstructive territories showed significant effects on range of motion while etiology and time between injury and reconstruction showed no impact on the functional outcome. Classification of neck territories aids in improving outcomes while minimizing donor morbidity. The central above territory, when reconstructed with free flaps, yielded the most rewarding improvement. A classification and treatment algorithm aids in achieving significant improvements in range of neck motion while taking into consideration the donor sites.

Mesothelial/monocytic incidental cardiac excrescences of the heart: case report and literature review

Mesothelial/monocytic incidental cardiac excrescences (MICE) of the heart are rare benign entities that have only been diagnosed incidentally, following cardiac surgical procedure. To date, totally 35 cases have been reported in the English literature. We describe an additional case of cardiac MICE presenting with severe aortic regurgitation for aortic valve replacement in a 20-year-old Chinese male patient. On microscopic examination, the findings initially were confused with true neoplasm. However, the related gross appearance, clinical history and further immunohistochemical staining enabled an accurate diagnosis. We review the relevant literature and found that immunohistochemical staining, especially the anti-cytokeratin antibody (AE1/AE3) and KP1 (CD-68) that were used by most investigators previously, was significant while making the diagnosis, because the two components of the cells show a contrast immunoreactivity to these two makers. The pathologists should always be alert to this entity while diagnose a cardiac surgery specimen.

Concentrations of airborne culturable bacteria in 100 large US office buildings from the BASE study

This paper presents summary statistics of airborne culturable bacteria from the US Environmental Protection Agency Building Assessment Survey and Evaluation (BASE) study. Air samples were collected with single-stage, multiple-hole, agar impactors in 100 large office buildings in 1994-1998 to obtain normative data on indoor environmental quality. Bacterial concentrations were compared by incubation temperature, location, season, and climate zone. Forty-one percent of the samples were below the 2- or 5-min detection limits (18 or 7 CFU/m3, respectively) but less than 1% were overgrown. Mesophilic bacteria (30 degrees C) accounted for >95% of culturable bacteria, both indoors and outdoors. Average concentrations were higher outdoors, except for Gram-positive cocci, which were the only group that were significantly higher indoors (39 vs. 24 CFU/m3), and Gram-negative cocci, for which both concentrations were low and the difference were not significant. Outdoor concentrations of culturable bacteria were somewhat higher in winter (194 vs.165 CFU/m3), and the two dominant outdoor groups were unknown bacteria and Gram-positive rods. Conversely, indoor concentrations were significantly higher in summer (116 vs. 87 CFU/m3), consisting primarily of unknown bacteria and Gram-positive cocci. Bacterial concentrations were within the ranges reported in previous studies of non-problem buildings, and the extreme aggregated indoor concentrations (e.g. the 90th percentile, 175 CFU/m3) of these 100 representative buildings may serve as upper bounds to develop interpretation guidelines for office environments and similar non-manufacturing workplaces in various climate zones.

PRACTICAL IMPLICATIONS

The Building Assessment Survey and Evaluation (BASE) study was one of the most comprehensive investigations of indoor environmental quality in which a standardized protocol was used to measure bioaerosols in 100 typical US office buildings. The information on the indoor and outdoor concentrations of airborne bacteria in different climate zones during the heating and cooling seasons has expanded the baseline data available for interpretation of measurements from building investigations. With suggested refinements, the BASE protocol may serve as a guide for future studies of bioaerosol concentrations, building characteristics, and occupant perceptions of the indoor environment.

Concentrations of cat and dust-mite allergens in dust samples from 92 large US office buildings from the BASE Study

The concentrations of cat (Fel d1) and dust-mite (Der f1 and Der p1) allergens were measured in 92 large office buildings in the US Environmental Protection Agency's Building Assessment Survey and Evaluation (BASE) Study (251 dust samples; one to four samples per building). Fel d1 was detected in almost all buildings and samples (91 buildings, 99%; 235 samples, 94%; range: <0.01-19 microg/g; median: 0.3 microg/g). Cat allergen exceeded 1 microg/g (a lower symptom threshold) in 56 samples (22%) from 45 buildings, but exceeded 8 microg/g (a sensitization threshold) in only two samples (1%) from two buildings. Der f1 or Der p1 was found in approximately half of all buildings and samples (63 and 70% of buildings; 45 and 51% of samples; range: <0.01-53 microg/g and <0.01-25 microg/g; median: <0.02 and 0.03 microg/g, respectively). Mite allergen exceeded 2 microg/g (a sensitization threshold) in seven samples (3%) from five buildings and exceeded 10 microg/g (a symptom threshold) in three samples (1%) from three buildings. Fel d1 concentration was significantly higher in samples collected in summer (June to September, 48 buildings), but cat allergen was not correlated with either mite allergen. Der f1, but not Der p1, concentration tended to be higher in samples collected in winter (December to April, 44 buildings), and the two mite allergens were significantly correlated only in winter. Cat and mite allergens were detected in 78% of representative US office buildings, but the concentrations seldom exceeded levels associated with sensitization or symptom provocation.

PRACTICAL IMPLICATIONS

The information on the concentrations of cat and dust-mite allergens in representative large US offices has expanded the baseline data available for interpretation of measurements from other building investigations. With suggested refinements, the BASE protocol for measurement of allergen concentrations in dust samples may serve as a guide to future studies of building characteristics, bioaerosol concentrations, and occupant perceptions of the indoor environment.

The role of glottal gap in predicting aspiration in patients with unilateral vocal paralysis

Aspiration has been frequently noted among patients suffering from vocal-fold paralysis. The association between a defect of glottal closure and aspiration in patients with unilateral vocal paralysis appears to have been rarely reported. The current study reviews collected data consisting of videotaped flexible nasoendoscopy and stroboscopy for patients with a unilateral vocal-fold paralysis. Mean normalized glottal gap areas for patients suffering vocal paralysis with associated aspiration are significant greater than that for the non-aspiration group. Subsequent to the surgical correction of the glottal gap, all patients recovered well from their earlier aspiration. The investigation of objectively derived data revealed that poor airway protection due to incomplete closure of the vocal fold was the major cause of aspiration for patients suffering unilateral vocal-fold paralysis. Intracordal autologous fat injection can successfully improve the breath control and eliminate aspiration in patients with vocal-fold paralysis.

Extended Trapezius Myocutaneous Free Flap for the Reconstruction of a Foot Defect Lacking Adjacent Recipient Vessels

Foot reconstruction requires tissue that is durable and can withstand the extremes of pressure and stress. The trapezius myocutaneous flap has not been used previously as a free flap for foot reconstruction. In this report, the trapezius was used as an extended myocutaneous free flap for the reconstruction of a foot wound lacking adjacent and adequate recipient vessels. The extended trapezius flap may be one of the longest free flaps that can be harvested. The indications for the use of this flap are limited. In an extremity that lacks adequate recipient vessels adjacent to the defect, this flap can be extended such that more proximal vessels in the leg can be used as the recipient vessels without the need for vein grafts to bridge the distance. The donor-site morbidity of this flap is minimal when the superior fibers of the trapezius muscle and its innervation are preserved.

Double free flaps harvested from one or two donor sites for one or two-staged burn reconstruction: models of sequential-link and independent-link microanastomoses

Extensive burn injuries and subsequent scarring result in functional and aesthetic impairments. The use of free flaps in burn reconstructions provides superior outcomes especially when other, more conservative reconstructive methods fail and curtail efforts of relentless rehabilitation. Multiple chronic scar-associated problems and extensive acute burn defects are conventionally resolved by multiple procedures. Thus, two or extensive scar regions are typically reconstructed using two free flaps (double free flaps) in two separate, procedures utilizing two independent donor sites. This leads to a protracted course of repetitive operations, hospitalizations, and rehabilitation, causing a prolonged period of discomfort and disability. The definition of double free flaps is two independent free flaps with two sets of microanastomoses. This paper illustrates, via a case-series, that double free flaps could be performed in one procedure, with both flaps harvested from either one or two donor sites. Two flaps are then utilized to resolve one large or two problem areas at the same time. Revascularization of the flaps is achieved via either a sequential-link or independent-link microanastomoses. The advantages of harvesting double free flaps from one region and using them in one stage to reconstruct one or two defect area include: (1) providing a large area of soft, pliable skin from one region for re-surfacing burn injuries or resolving scar associated problems, (2) decreasing the treatment course and potential disability, (3) decreasing donor site morbidities, (4) increasing maneuverability and conformability of the flap, and (5) affording a better functional and aesthetic outcome.

Free Split-Cutaneous Perforator Flaps Procured Using a Three-Dimensional Harvest Technique for the Reconstruction of Postburn Contracture Defects

With recent advances in free-tissue transfer, microsurgical techniques have been used more frequently for the reconstruction of postburn contracture defects. Traditional methods, including full-thickness skin grafts and local flaps, often result in a good outcome; however, multiple operative procedures, long periods of splinting, and physical rehabilitation are often required. Free split-cutaneous perforator flaps, consisting of one large cutaneous paddle with two perforating vessels split into two separate skin regions, were used for two kinds of postburn contractures: rectangular and spatially separate defects. From September of 2000 to October of 2002, seven patients underwent this method of reconstruction at Chang Gung Memorial Hospital in Taiwan. A three-dimensional flap harvest method, in which the skin paddle is circumferentially elevated early in the harvest, was used. Postburn scar contractures had resulted from flame burns in six cases and an electric burn in one case. The reconstructive regions included the neck in two patients, the breast in one patient, and the hand in four patients. There were six male patients and one female patient, with a mean age of 34.8 years (range, 25 to 49 years). The size of the excised scar ranged from 120 cm2 to 308 cm2 (mean, 162.3 cm2). The size of the unsplit flaps ranged from 144 cm2 to 337.5 cm2 (mean, 192.1 cm2). The average time for flap harvest using this three-dimensional harvest technique was 39.1 minutes. The average total operative time was 4.3 hours. The average total hospital stay was 7.3 days (range, 6 to 11 days). All flaps survived without major complications. The donor site was closed primarily in all cases. At a mean follow-up time of 9 months, the functional and aesthetic outcomes showed significant improvement as compared with the preoperative condition. In this study, a new method of flap harvest using a three-dimensional technique is introduced, and its application in the reconstruction of postburn contractures is evaluated.

A new method: perforator-based tissue expansion for a preexpanded free cutaneous perforator flap

Recent advances in concepts of preexpanded free flaps have made it possible to replace larger postburn contracture area. Free anterolateral thigh (ALT) cutaneous perforator flaps are popular due to constant, reliable anatomy and various clinical applications in our department. Combination of preexpansion, perforator-based prefabrication of tissue expansion and a free anterolateral thigh flap is first introduced and developed to resurface the large territory of postburn cervical contracture in a 33-year-old female patient with second to third degree flame burn with a 45% total body surface area (TBSA) involvement. The limited lateral flexion and rotation was noted despite aggressive rehabilitation for 6 months. The 650cm(3) kidney-shaped tissue expander was inserted around the myocutaneous perforator under the fascia via the midlateral thigh incision in first stage. Two months later right lateral neck scar (size=25cm x 13cm) was excised after serial clinic saline injection. The preexpanded free flap (size=29cm x 15cm) combined with z plasty and capsulectomy was harvested and covered in the contracture defect. A flap totally survived. One-staged resurfacing was achieved with immediate postoperative improvement. The hospital stay was 6 days. The donor site was closed primarily. After 6 months follow-up, the functional improvement was assessed as follows: an increase in rotation of 14 degrees (preoperative 74 degrees to postoperative 88 degrees ); and an increase in lateral flexion of 10 degrees (preoperative 30 degrees to postoperative 40 degrees ). The prefabrication of the free cutaneous perforator flap by perforator-based tissue expansion above the muscle has several advantages: (1) it provides accurate and safe expansion without damage of any perforator compared with the blunt dissection; (2) larger territory of free flaps can be used for burn reconstruction; (3) donor site is primarily closed with low tension; (4) it is not a random expanded flap due to direct expansion of specific skin territory around the perforator. The disadvantages are two-staged procedures, complications of tissue expansion (e.g. infection, extrusion), the possibility of compression of pedicles.

Electric water heaters: a new hazard for pediatric burns

The electric water heater has recently become a popular household appliance replacing the hot water dispensing jug. This device provides hot water and potable cool water directly from the faucets thus removing the need to refill the container or boil water separately in a kettle. Along with the convenience of dispensing hot water immediately has come an increased incidence of pediatric burns. This paper presents a 6-year retrospective study of such pediatric scald burns from 1996 to 2001. Computer database records revealed that the incidence of pediatric scald burns caused by the electric water heater during the past 6 years was 6.4% (66/1028). The age of victims ranged 0-6 years (mean 1.5+/-1.1 years), most of the victims were in the 1-2-year-old group. In most common cases burn location was the trunk. The accidents often occurred during the cold months and in the living room of the house. From this retrospective study, it was seen that the etiology and incidence of scald burns among children have changed as people have modified their household practice for obtaining hot water in our country. This study aims to increase public awareness to the problem and suggest some prevention measures to reduce this type of scald injury.

The thigh as a model for free style free flaps

Following a set of principles, free style free flaps may be harvested from any region of the body where a Doppler signal is heard. By using a retrograde dissection technique, the skin vessel is traced through its subfascial course (intramuscular or septocutaneous), until adequate length or vessel size is achieved. If a "free style free flap" is not originally planned, this approach can be usedwhen anatomic variations or unexpected events are encountered. The thigh, a region that is familiar to the surgical team at Chang Gung Memorial Hospital, was chosen as the site to begin exploring this style of flap harvest. Nine flaps were harvested as free style free flaps from the thigh and were used successfully for the reconstruction of complex defects.

Use of the free vastus lateralis flap in skull base reconstruction

Free flaps in skull base reconstruction are indicated for providing an effective separation of the intracranial cavity from the oronasal space, for eliminating a dead space, and for the treatment of established wound complications such as dural exposures and cerebrospinal fluid leaks. Seven patients with cranial base defects underwent reconstructions using a free vastus lateralis muscle flap. In two cases, a vastus lateralis flap was raised to incorporate the anterolateral thigh skin as a myocutaneous flap. In four cases, a free flap was indicated for reconstruction following tumor ablation, and in three cases, for the resolution of wound or cerebrospinal fluid leak complications following previous cranial base surgery. All flaps were successful, with no partial failures. In those patients undergoing tumor ablative surgery, the cranial cavity was effectively sealed from the oronasal cavity. Patients with established wound complications following previous cranial base surgery had a complete resolution of their symptoms. This report discusses the suitability of the vastus lateralis flap for skull base reconstruction in terms of the availability of adequate muscle volume to fill dead space, vascularized fascia to augment dural repairs, and the freedom to use skin if required for internal lining or external skin cover. This flap also provides an extremely long pedicle, allows simultaneous flap harvest, and has low donor site morbidity.

Use of free thin anterolateral thigh flaps combined with cervicoplasty for reconstruction of postburn anterior cervical contractures

Free thin anterolateral thigh flaps combined with cervicoplasty were used in a series of seven patients undergoing reconstruction for previous burn injury from September of 2000 to May of 2001 at Chang Gung Memorial Hospital. This method uses a suprafascial dissection technique to provide a thin flap to improve cervical contour. Neck contractures had resulted from flame burns in six patients and from a chemical burn in one patient. The mean age was 32.7 years (range, 22 to 45 years). The size of excised scar ranged from 10 x 2 cm to 26 x 5 cm (mean, 19.7 x 3.3 cm). The size of flaps ranged from 11 x 5 cm to 26 x 8 cm (mean, 21.3 x 6.5 cm). Average operative time was 6 hours. Average hospital stay was 10 days. All flaps survived, with one flap sustaining partial marginal loss. The donor site was closed primarily in five cases and by using a split-thickness skin graft in two cases. At a mean follow-up time of 5 months, the functional improvement was measured as follows: a mean increase in extension of 30 degrees (preoperatively, 95 degrees; postoperatively, 125 degrees), a mean increase in rotation of 18 degrees (preoperatively, 59 degrees; postoperatively, 77 degrees), and a mean increase in lateral flexion of 12.5 degrees (preoperatively, 26.5 degrees; postoperatively, 39 degrees). The average cervicomandibular angle was improved by 25 degrees (preoperatively, 145 degrees; postoperatively, 120 degrees). This series demonstrates that the use of free thin anterolateral thigh flaps combined with cervicoplasty provides a one-stage reconstruction with a thin, pliable flap that achieves good cervical contour with low donor-site morbidity.

Reconstruction of through-and-through cheek defects involving the oral commissure, using chimeric flaps from the thigh lateral femoral circumflex system

Repairing full-thickness cheek defects involving the oral commissure in the head and neck regions after tumor resection is a challenge for reconstructive surgeons. First, they are usually relatively large defects. Second, the axes of the cheek and intraoral lining are different from each other. Third, the shape and volume of the defect and the oral sphincter should be considered individually. Lateral femoral circumflex perforator flaps with at least two independent cutaneous perforators are suitable for reconstruction of such a defect in one stage. In this study, between January and December of 1999, a total of nine patients underwent reconstruction with chimeric lateral femoral circumflex perforator flaps immediately after resection of their oral cancers. The average age of the patients was 61 years (range, 42 to 74 years). The oral lining defects were between 5 x 5 cm and 6 x 12 cm in size, whereas the cheek defects were between 5 x 6 and 8 x 12 cm. Fifteen flaps were supplied by one perforator, and three flaps were supplied by two perforators. There were nine single arterial anastomoses, eight single venous anastomoses, and one double venous anastomosis. There were no total flap failures. One case of postoperative venous congestion was successfully treated by a second venous anastomosis. The average duration of hospitalization was 31.8 days (range, 18 to 49 days). The median follow-up time was 8.6 months, and all patients were alive at the time of evaluation. Six of nine patients had satisfactory or good contours of the cheek. Five of nine patients had normal deglutition. Six of nine patients had adequate oral continence. Compared with other free flaps, use of the combined (chimeric) lateral femoral circumflex perforator flaps for the reconstruction of cheek through-and-through defects involving the oral commissure has several advantages: (1) easy three-dimensional insetting, (2) a unique character suitable for the requirements of the oral lining and cheek skin to achieve good aesthetic appearance, (3) functional preservation of the oral sphincter and the resistance of gravity by use of the tensor fasciae latae, (4) minimal donor-site morbidity, (5) economic design, and (6) no need for microsurgical fabrication, because major vascular branches such as the transverse branch, the ascending branch, and the feeding branch to the rectus femoris muscle are not sacrificed in the procedure. The disadvantages of these flaps include (1) the complicated anatomy of the perforators, (2) the learning-curve requirement for their use, and (3) the occasional need for secondary venous drainage and shifts to double flaps. Although there are some difficulties, it was concluded that use of the chimeric lateral femoral circumflex perforator flaps in the selected cases is one of the good options available for the reconstruction of cheek through-and-through defects involving the oral commissure.

Microsurgical medialis pedis flaps for reconstruction of soft-tissue defects in the hand

The medialis pedis flap (MPF) has been used for the reconstruction of soft-tissue defects in the hand since 1990. From January 1997 through January 2000, 19 patients (15 male, 4 female) with hand injuries underwent microsurgical MDF reconstruction at Chang Gung Memorial Hospital. There were finger injuries in 16 patients and palm defects in 3 patients. The mean patient age was 32.6 years (age range, 16-58 years). Flap size ranged from 4.5 x 2 cm to 7 x 6 cm (mean, 6 x 2.8 cm). Only one flap had partial loss. The donor site was closed primarily in 9 patients, and was closed using a split-thickness skin graft in 9 patients and a full-thickness skin graft in 1 patient. At a mean follow-up of 13 months, the protective sensation was 16 mm using the static two-point discrimination test and was 10 mm using the moving two-point discrimination test. Based on this retrospective study the authors conclude that (1) the MPF has the advantages of thin and glabrous skin, (2) the size of pedicle is compatible with the recipient vessel in the hand, (3) there is low donor site morbidity, and (4) achieving protective sensation is possible.

Sixteen-year experience with 1,000 heart transplants at UCLA

1. The consecutive pre- and post-1994 eras have demonstrated improved survival for all age groups. This is linked to improved preservation methods, surgical technique and immunosuppression agents. 2. The use of marginal donor hearts for Status I and alternate elderly patients has followed the model of matching donor and recipient risk without affecting patient outcome and minimized the use of implantable assist devices. 3. A donor history of systemic gram-negative infection, hypertension, or traumatic intracranial bleeds was an important marker for risk. Younger age and shorter ischemia time could compensate for other hazards. 4. Heart transplantation in carefully selected elderly recipients yielded clinical results similar to those of younger patients with less rejection. 5. An adult alternate recipient list proved useful to prevent diversion of standard donors away from younger recipients. 6. Retransplantation for TCAD is acceptable but much less satisfactory for acute graft failure. 7. Trends show an increase in the use of implantable devices; refinement in technology for mechanical assist and replacement is forthcoming.

Concurrent thrombosis of cerebral and femoral arteries in a patient with nephrotic syndrome

Although venous thrombosis is a frequently encountered problem in nephrotic syndrome, the occurrence of arterial thrombosis is much less common, and is usually associated with a poor prognosis. To the best of our knowledge, there has been only one reported case of concurrent cerebral and femoral artery thrombosis, that of a 23-year-old male who finally died. Herein, we report a case of a 35-year-old woman with nephrotic syndrome. She developed cerebral and femoral arterial thrombosis simultaneously when the nephrotic syndrome relapsed. Immediate thrombectomy of the femoral artery, followed by anticoagulation and immunosuppressive therapy, were employed. The patient recovered completely and is now doing well. Our experience indicates that multiple artery thrombosis in nephrotic patients may not necessarily carry a poor outcome if early and aggressive treatment can be undertaken.

Studies of a magnetically focused electrostatic mirror. I. Experimental test of the first order properties

When a uniform magnetic field is superimposed on a uniform electrostatic field, the combination can act as a magnetically focused mirror. This mirror is predicted to have aberrations of opposite sign to those of a magnetic lens and may therefore be useful as a corrector. We have built an electron optical system to test these ideas. The results are presented in two papers. This first paper describes the general design and the results of the measurements of the first order properties. The second paper (Tsai, F., J. Microsc. 197 (2000) 118-135) will describe the measurements of the aberration properties.

Studies of a magnetically focused electrostatic mirror. II. Aberration corrections

A magnetically focused electrostatic mirror is shown to be able to correct the spherical and chromatic aberrations of a probe forming system simultaneously. The probe forming system comprises a uniform magnetic lens and a uniform electrostatic mirror. Previous theoretical investigations showed that the spherical and chromatic aberration coefficients of these two components are the same values but with opposite sign, whose combination will therefore be free from aberrations. The experimental arrangement used a solenoid to produce a uniform magnetic field, and a series of plate electrodes to produce a uniform electrostatic field. These fields are shown to satisfy the experimental requirements. By deliberately changing the extraction voltage to defocus the electron beam, the author is able to observe correction of chromatic aberration by one order of magnitude. By deliberately changing the lens field and the mirror field, the author is able to observe the reduction of the asymmetry caused by the spherical aberration, which the author believes also indicates correction by one order of magnitude.

Indoor/outdoor PM10 and PM2.5 in Bangkok, Thailand

Twenty-four-hour averaged PM10 and PM2.5 concentrations were obtained by using 4-liter-per-minute-pumps and impactors in microenvironments of a busy shopping district and a university hospital campus. In both areas, most people live directly adjacent to their worksites--minimizing the need to measure commuting exposure as part of total daily exposure. Co-located samplers were set in indoor microenvironments, the near-ambient zone of the households, and at nearby streetside central ambient monitoring stations. Smoking and use of other indoor PM sources were recorded daily via questionnaires. Consistent with previous studies, smoking and the use of charcoal stoves increased indoor particulate matter levels. The sampled air-conditioned hospital area had substantially lower particle concentrations than outdoors. A simple total exposure model was used to estimate the human exposure. The averaged ratios of co-located PM2.5/PM10 concentrations in various microenvironments are reported for each location. A single daily indoor average PM10 concentration for all households measured in a given sampling day is calculated for correlation analysis. Results showed that day-to-day fluctuations of these calculated indoor PM10 levels correlated well with near-ambient data and moderately well with ambient data collected at the nearby central monitoring site. This implies that ambient monitors are able to capture the daily variations of indoor PM levels or even personal exposure and may help explain the robust association of ambient PM levels and health effects found in many epidemiological studies. Absolute PM exposures, however, were substantially underestimated by ambient monitors in the shopping district, probably because of strong local sources.

Blunt trauma with flail chest and penetrating aortic injury

Blunt chest trauma with flail chest is common. The mortality attributes initially to the associated pulmonary contusion, massive hemothorax and later to the occurrence of adult respiratory distress syndrome. We report a case of flail chest with segmental fractures near the costovertebral junction and delayed hemothorax attacked 14 h later. The final diagnosis of the penetrating aortic injury by detached rib fragment was appreciated by aortogram. Unfortunately, active aortic hemorrhage made prompt thoracotomy in vain for life salvage.