Efficacy of Pulsed Electromagnetic Therapy for Chronic Lower Back Pain: A Randomized, Double-blind, Placebo-controlled Study

This randomized, double-blind, placebo-controlled clinical trial studied the effectiveness of pulsed electromagnetic therapy (PEMT) in patients with chronic lower back pain. Active PEMT ( n = 17) or placebo treatment ( n = 19) was performed three times a week for 3 weeks. Patients were assessed using a numerical rating scale (NRS) and revised Oswestry disability scores for 4 weeks after therapy. PEMT produced significant pain reduction throughout the observation period compared with baseline values. The percentage change in the NRS score from baseline was significantly greater in the PEMT group than the placebo group at all three time-points measured. The mean revised Oswestry disability percentage after 4 weeks was significantly improved from the baseline value in the PEMT group, whereas there were no significant differences in the placebo group. In conclusion, PEMT reduced pain and disability and appears to be a potentially useful therapeutic tool for the conservative management of chronic lower back pain.

Osteopontin neutralisation abrogates the liver progenitor cell response and fibrogenesis in mice

BACKGROUND

Chronic liver injury triggers a progenitor cell repair response, and liver fibrosis occurs when repair becomes deregulated. Previously, we reported that reactivation of the hedgehog pathway promotes fibrogenic liver repair. Osteopontin (OPN) is a hedgehog-target, and a cytokine that is highly upregulated in fibrotic tissues, and regulates stem-cell fate. Thus, we hypothesised that OPN may modulate liver progenitor cell response, and thereby, modulate fibrotic outcomes. We further evaluated the impact of OPN-neutralisation on murine liver fibrosis.

METHODS

Liver progenitors (603B and bipotential mouse oval liver) were treated with OPN-neutralising aptamers in the presence or absence of transforming growth factor (TGF)-β, to determine if (and how) OPN modulates liver progenitor function. Effects of OPN-neutralisation (using OPN-aptamers or OPN-neutralising antibodies) on liver progenitor cell response and fibrogenesis were assessed in three models of liver fibrosis (carbon tetrachloride, methionine-choline deficient diet, 3,5,-diethoxycarbonyl-1,4-dihydrocollidine diet) by quantitative real time (qRT) PCR, Sirius-Red staining, hydroxyproline assay, and semiquantitative double-immunohistochemistry. Finally, OPN expression and liver progenitor response were corroborated in liver tissues obtained from patients with chronic liver disease.

RESULTS

OPN is overexpressed by liver progenitors in humans and mice. In cultured progenitors, OPN enhances viability and wound healing by modulating TGF-β signalling. In vivo, OPN-neutralisation attenuates the liver progenitor cell response, reverses epithelial-mesenchymal-transition in Sox9+ cells, and abrogates liver fibrogenesis.

CONCLUSIONS

OPN upregulation during liver injury is a conserved repair response, and influences liver progenitor cell function. OPN-neutralisation abrogates the liver progenitor cell response and fibrogenesis in mouse models of liver fibrosis.

Stretchable liquid-crystal blue-phase gels

Liquid-crystalline polymers are materials of considerable scientific interest and technological value. An important subset of these materials exhibit rubber-like elasticity, combining the optical properties of liquid crystals with the mechanical properties of rubber. Moreover, they exhibit behaviour not seen in either type of material independently, and many of their properties depend crucially on the particular mesophase employed. Such stretchable liquid-crystalline polymers have previously been demonstrated in the nematic, chiral-nematic, and smectic mesophases. Here, we report the fabrication of a stretchable gel of blue phase I, which forms a self-assembled, three-dimensional photonic crystal that remains electro-optically switchable under a moderate applied voltage, and whose optical properties can be manipulated by an applied strain. We also find that, unlike its undistorted counterpart, a mechanically deformed blue phase exhibits a Pockels electro-optic effect, which sets out new theoretical challenges and possibilities for low-voltage electro-optic devices.

Myofibroblastic cells function as progenitors to regenerate murine livers after partial hepatectomy

OBJECTIVE

Smoothened (SMO), a coreceptor of the Hedgehog (Hh) pathway, promotes fibrogenic repair of chronic liver injury. We investigated the roles of SMO+ myofibroblast (MF) in liver regeneration by conditional deletion of SMO in α smooth muscle actin (αSMA)+ cells after partial hepatectomy (PH).

DESIGN

αSMA-Cre-ER(T2)×SMO/flox mice were treated with vehicle (VEH) or tamoxifen (TMX), and sacrificed 24-96 h post-PH. Regenerating livers were analysed for proliferation, progenitors and fibrosis by qRT-PCR and quantitative immunohistochemistry (IHC). Results were normalised to liver segments resected at PH. For lineage-tracing studies, αSMA-Cre-ER(T2)×ROSA-Stop-flox-yellow fluorescent protein (YFP) mice were treated with VEH or TMX; livers were stained for YFP, and hepatocytes isolated 48 and 72 h post-PH were analysed for YFP by flow cytometric analysis (FACS).

RESULTS

Post-PH, VEH-αSMA-SMO mice increased expression of Hh-genes, transiently accumulated MF, fibrosis and liver progenitors, and ultimately exhibited proliferation of hepatocytes and cholangiocytes. In contrast, TMX-αSMA-SMO mice showed loss of whole liver SMO expression, repression of Hh-genes, enhanced accumulation of quiescent HSC but reduced accumulation of MF, fibrosis and progenitors, as well as inhibition of hepatocyte and cholangiocyte proliferation, and reduced recovery of liver weight. In TMX-αSMA-YFP mice, many progenitors, cholangiocytes and up to 25% of hepatocytes were YFP+ by 48-72 h after PH, indicating that liver epithelial cells were derived from αSMA-YFP+ cells.

CONCLUSIONS

Hh signalling promotes transition of quiescent hepatic stellate cells to fibrogenic MF, some of which become progenitors that regenerate the liver epithelial compartment after PH. Hence, scarring is a component of successful liver regeneration.

Epidermal growth factor receptor is related to poor survival in glioblastomas: single-institution experience

PURPOSE

There are conflicting results surrounding the prognostic significance of epidermal growth factor receptor (EGFR) status in glioblastoma (GBM) patients. Accordingly, we attempted to assess the influence of EGFR expression on the survival of GBM patients receiving postoperative radiotherapy.

MATERIALS AND METHODS

Thirty three GBM patients who had received surgery and postoperative radiotherapy at our institute, between March 1997 and February 2006, were included. The evaluation of EGFR expression with immunohistochemistry was available for 30 patients. Kaplan-Meier survival analysis and Cox regression were used for statistical analysis.

RESULTS

EGFR was expressed in 23 patients (76.7%), and not expressed in seven (23.3%). Survival in EGFR expressing GBM patients was significantly less than that in non-expressing patients (median survival: 12.5 versus 17.5 months, p=0.013). Patients who received more than 60 Gy showed improved survival over those who received up to 60 Gy (median survival: 17.0 versus 9.0 months, p=0.000). Negative EGFR expression and a higher radiation dose were significantly correlated with improved survival on multivariate analysis. Survival rates showed no differences according to age, sex, and surgical extent.

CONCLUSION

The expression of EGFR demonstrated a significantly deleterious effect on the survival of GBM patients. Therefore, approaches targeting EGFR should be considered in potential treatment methods for GBM patients, in addition to current management strategies.

Blue-phase templated fabrication of three-dimensional nanostructures for photonic applications

A promising approach to the fabrication of materials with nanoscale features is the transfer of liquid-crystalline structure to polymers. However, this has not been achieved in systems with full three-dimensional periodicity. Here we demonstrate the fabrication of self-assembled three-dimensional nanostructures by polymer templating blue phase I, a chiral liquid crystal with cubic symmetry. Blue phase I was photopolymerized and the remaining liquid crystal removed to create a porous free-standing cast, which retains the chiral three-dimensional structure of the blue phase, yet contains no chiral additive molecules. The cast may in turn be used as a hard template for the fabrication of new materials. By refilling the cast with an achiral nematic liquid crystal, we created templated blue phases that have unprecedented thermal stability in the range -125 to 125 °C, and that act as both mirrorless lasers and switchable electro-optic devices. Blue-phase templated materials will facilitate advances in device architectures for photonics applications in particular.

Synovial chondromatosis in the temporomandibular joint: a case with typical imaging features and pathological findings

Synovial chondromatosis of the temporomandibular joint is a rare benign joint disorder that has been reported in only a few studies. However, we recently encountered a pathologically proven case of this disorder. This case also showed the typical imaging findings on panoramic radiographs and on CT and MR images. Therefore, we report this case and the imaging and pathological findings.

Outer retinal abnormalities associated with inner retinal pathology in nonglaucomatous and glaucomatous optic neuropathies

Inner and outer retinal morphology were quantified in vivo for 6 nonglaucomatous and 10 glaucomatous optic neuropathy patients. Custom, ultrahigh-resolution imaging modalities were used to evaluate segmented retinal layer thickness in 3D volumes (Fourier-domain optical coherence tomography), cone photoreceptor density (adaptive optics fundus camera), and the length of inner and outer segments of cone photoreceptors (adaptive optics-optical coherence tomography). Quantitative comparisons were made with age-matched controls, or by comparing affected and nonaffected retinal areas defined by changes in visual fields. The integrity of outer retinal layers on optical coherence tomography B-scans and density of cone photoreceptors were correlated with visual field sensitivity at corresponding retinal locations following reductions in inner retinal thickness. The photoreceptor outer segments were shorter and exhibited greater variability in retinal areas associated with visual field losses compared with normal or less affected areas of the same patient's visual field. These results demonstrate that nonglaucomatous and glaucomatous optic neuropathies are associated with outer retinal changes following long-term inner retinal pathology.

Detection and characterization of enterovirus associated with herpangina and hand, foot, and mouth disease in Seoul, Korea

BACKGROUND

Human enteroviruses (HEVs) are a major cause of herpangina, HFMD (hand, foot, and mouth disease), and other neurological diseases in Seoul, Korea.

METHODS

A total of 56 specimens from hospitalized patients collected from February to December 2009 (37 females and 19 males) in Seoul were tested for HEV from stool, throat swab, and vesicle swab samples taken from patients with herpangina or HFMD using cell culture and RT-PCR in 2009. By the 1D gene, encoding the VP1 capsid protein, seven different HEV genotypes were detected with Coxsackievirus A2, A4, A5, A9, A16 (CA), Coxsackievirus B1 (CB), and Enterovirus 71 (EV71). The most prevalent genotype was CA16 (6, 10.7%), followed by CA2 (4, 7.1%), CA5 (4, 7.1%), EV71 (2, 3.6%), CA4 (1, 1.8%), CA9 (1, 1.8%), and CB1 (1, 1.8%). The 1D gene sequences of two EV71 strains were closely related with one another (98.5% nucleotide similarity) and belonged to the C4 genotype.

CONCLUSIONS

It is important to continuously survey the genetic characteristics of EV71 and CA16 from patients, which will provide useful data that aids in our understanding of HFMD infections in Seoul, Korea and may contribute to future control.

Viral agents associated with acute gastroenteritis in Seoul, Korea

BACKGROUND

The present study was carried out to describe the epidemiologic characteristics of viral gastroenteritis and determine the phylogenetic composition of norovirus strains detected in hospitalized children with acute gastroenteritis in Seoul, Korea.

METHODS AND RESULTS

In total, 10,603 stool samples were collected from 2004 to 2008 and tested by RT-PCR or ELISA. In 4,170 (39.3%) samples at least one viral pathogen was present. Rotavirus (RoV) (1,864, 17.5%) was found to be the causative agent followed by norovirus (NoV) (1,845, 17.4%), human adenovirus (HAdV) (266, 2.5%), human astrovirus (HAstV) (194, 1.8%), and sapovirus (SV) (1, 0.009%). Five GI genotypes (GI-1, GI-3, GI-4, GI-8, and GI-9) and eight GII genotypes (GII-2, GII-3, GII-4, GII-6, GII-7, GII-12, GII-16, and GII-17) of NoV were identified in acute gastroenteritis patients in 2008.

CONCLUSIONS

The genetic characteristics of norovirus and the epidemiologic patterns of a viral pathogen from acute gastroenteritis patients may give potentially effective data for epidemiological studies in Seoul, Korea.

Diffusion MR imaging of hypoglycemic encephalopathy

BACKGROUND AND PURPOSE

MR imaging features of HE have not been fully established. The purpose of this study was to determine the topographic distribution and DWI findings of HE.

MATERIALS AND METHODS

We retrospectively evaluated HE MR imaging (n = 11). The topographic distribution of the lesions was evaluated on routine MR imaging, and DWI SI and ADC values were assessed. The ADC value of involved lesions was compared with the noninvolved subcortical WM area by use of the paired t test.

RESULTS

MR images demonstrated bilateral diffusion-restrictive lesions in the posterior limb of the IC (n = 6), cerebral cortex (n = 8), CR (n = 7), CS (n = 9), hippocampus (n = 4), and BG (n = 1). The mean ADC value of lesions was 448.82 +/- 92.34 x 10(-6) mm(2)/s compared with the mean ADC value of noninvolved lesions (837.72 +/- 62.14 x 10(-6) mm(2)/s); this difference was statistically significant (P < .000). The lesions showed complete resolution on follow-up DWI for 6 patients. Three patients with cortical involvement of > or = 2 lobes showed partial recovery or death, but most of the other patients with WM involvement or cortical involvement in only 1 lobe experienced complete recovery.

CONCLUSIONS

The topographic localization of the lesions was the posterior limb of the IC, cerebral cortex, CR, CS, hippocampus, and BG. Most HE lesions probably correspond to areas of reversible cytotoxic edema as seen on DWI, which can predict the prognosis of HE according to the degree of lesion extent.

Pituitary hemorrhage : classification and related factors

OBJECTIVE

Clinical features of pituitary hemorrhage vary from asymptomatic to catastrophic. The purpose of this study was to evaluate the factors related to severity of hemorrhage of pituitary adenoma.

METHODS

Pituitary hemorrhage was noted in 32 of 88 patients who underwent operations between January 2000 and December 2007. Clinical status was classified into group I (no hemorrhage symptoms), II (mild to moderate symptoms without neurological deficit), and III (with neurological deficit), and was compared to radiological, pathological, and operative findings. All patients were operated by transsphenoidal approach, and hemorrhage-related symptoms were relieved.

RESULTS

Groups I, II, and III comprised 15, 10 and 7 patients, respectively. In group I, hemorrhage volume was under 1 mL in 11 (73.3%), but, it was above 1 mL in 7 (70%) of group II and in all cases of group III. Hemorrhage stage based on MRI findings was chronic or subacute in 11 (73.3%) of group I, acute in 6 (60%) of group II, and acute or hyperacute in 6 (85.7%) of group III. Pathological examination revealed chronic-stage hematomas in 5 (50%) group II patients. Functioning adenomas were found in 5 (33.3%) group I patients but none in group II or III patients. Silent adenomas were found in 4 (26.7%), 8 (80%), and 3 (42.9%) in groups I, II, and III, respectively.

CONCLUSION

Clinical features of pituitary hemorrhage may differ with the radiological and immunohistopathlogical findings. Persistent symptoms are related to the chronic stage of hematoma requiring surgery for symptom relief. Neurological deficits are caused by large amount of acute hemorrhage requiring emergency operation. Silent adenoma is related to the severity of pituitary hemorrhage.

Loss of mitochondrial membrane potential and caspase activation enhance apoptosis in irradiated K562 cells treated with herbimycin A

PURPOSE

We previously reported that herbimycin A (HMA) alters the mode of cell death of K562 cells induced by radiation and enhanced their radiosensitivity. In the present study, we explored the apoptosis-inducing activity of HMA and the fundamental mechanism via which it regulates radiation-induced cell death.

MATERIALS AND METHODS

Chronic myelogenous leukemia (CML) cell line K562 was used. For X-irradiation and drug treatment, cells were plated at approximately 2x10(5) cells/ml. Exponentially growing cells were treated with 10 Gy of X-ray using a 6-MeV X-ray machine at a dose rate of 200-300 cGy/min. The cells were treated with 0.25 microM HMA immediately after irradiation and HMA remained for the entire culture period. The modes of cell death were discriminated by morphological changes, analysis of cell cycle, analysis of the mitochondrial events, and the expression of apoptosis-related proteins.

RESULTS

Our data demonstrates that radiation induced a significant time-dependent increase of cell death and failed to sustain a prolonged G2 arrest in K562 cells. Radiation-induced cell death caused the accumulation of cyclinB1 and weak nuclear fragmentation, suggesting a mitotic catastrophe. This mitotic catastrophe was dependent upon the mitochondrial permeability transition pore (PTP) opening and was independent of caspase-3. In contrast, K562 cells treated with radiation and HMA had an accelerated cell death and induced a p53-independent apoptosis. This apoptotic pathway was dependent upon an initial hyperpolarization of the mitochondrial inner membrane, following the release of cytochrome c and subsequent caspase-3 activation.

CONCLUSIONS

Two mechanisms of radiation-induced cell death in K562 cells, mitotic catastrophe and apoptosis, are regulated through distinct pathways, mitochondria and caspase-independent and -dependent, respectively. The findings of this study may provide new insights into improving the efficiency of radiotherapy in CML patients.

Investigation of structural transition of dsDNA on various substrates studied by atomic force microscopy

Structural transition of single dsDNA molecule which is immobilized on 3-aminopropyltriethoxysilane (APTES) treated substrate (APTES/substrate) or alkylthiol treated substrate (alkylthiol/substrate) has been investigated by atomic force microscopy (AFM). The obtained force versus distance (F-D) curves are used to dissect the transition from B-form to S-form, the melting from double stranded (ds) to single stranded (ss) DNA, and its Young's modulus as well as persistence length. The melt from dsDNA to ssDNA is evidenced by fitting with freely jointed chain (FJC) model. FJC fit and Young's modulus or persistence length values when the molecules are fixed on alkylthiol/substrate are more agreeable with other studies than those on APTES. We have clarified the different results of those experiments by analyzing the binding force between DNA molecules and APTES or alkylthiol linkers on the substrate. The DNA binding to APTES linker is much stronger than that on alkylthiol/substrate.

Spontaneous intraorbital hemorrhage: a case report

Intraorbital hemorrhage is a rare clinical condition caused by orbital trauma, surgery around the orbit, intraorbital vascular abnormalities, and neoplasm. It was reported to occur spontaneously without any known causes and in association with orbital pseudotumor in a very few cases. A 59-year-old, female patient admitted with sudden onset of severe exophthalmos and pain on the left eye. Orbital CT and MR imaging suggested hemorrhage in the upper part of retrobulbar area of the left orbit. Cerebral angiography was taken to rule out any possible vascular abnormalities. On the left carotid cerebral angiography, the run-off of the distal ophthalmic artery was not seen and the engorgement of the supraophthalmic artery was noted. Systemic administration of corticosteroid did not improve the clinical status and craniectomy was done and retrobulbar hematoma was removed, and the clinical symptoms and signs were improved. Authors report a case of spontaneous intraorbital hemorrhage with the clinical features similar to those of orbital pseudotumor, requiring surgical decompression.

The hedgehog pathway regulates remodelling responses to biliary obstruction in rats

BACKGROUND

Chronic biliary obstruction provokes fibrosis and accumulation of immature ductular cells. This fibroductular reaction resolves following biliary decompression, suggesting that it may also be involved in the repair of biliary damage. The hedgehog (Hh) pathway becomes activated in liver after bile duct ligation (BDL), and might modulate hepatic remodelling because Hh ligands are potent morphogens.

OBJECTIVE

To study the induction of the Hh pathway during progression and resolution of biliary fibrosis, and to clarify whether Hh signalling regulates accumulation of bile duct progenitor cells.

DESIGN AND MAIN OUTCOME MEASURES

Livers from rats with BDL were examined by quantitative real-time polymerase chain reaction analysis and immunohistochemistry to identify factors that might stimulate Hh signalling. BDL rats were subjected to Roux-en-Y hepaticojejunostomy (R-Y) to relieve biliary obstruction in order to determine whether these factors and Hh signalling declined as ductular populations and concomitant fibrosis regressed. Cultures of immature ductular cells were treated with putative Hh inducers and Hh ligands to confirm their functional relevance.

RESULTS

BDL increased expression of platelet-derived growth factor-BB (PDGF-BB) and sonic hedgehog (Shh), downregulated hedgehog-interacting protein (Hip), activated Hh signalling, and expanded populations of Hh-responsive ductular cells that expressed pancyotkeratin, a liver progenitor cell marker. After R-Y, Hip remained suppressed, expression of PDGF-BB and Shh gradually declined, and populations of hedgehog-responsive ductular cells regressed. In cultured ductular cells, PDGF-BB treatment induced Shh expression, and incubation with Shh inhibited apoptotic activity.

CONCLUSIONS

These results identify a mechanism for activation of the Hh pathway during cholestasis and suggest that Hh signalling regulates ductular cell accumulation after biliary injury.

Complicated giant diverticulum of the transverse colon accompanied by right inguinal hernia of the greater omentum

Giant colonic diverticulum is a very rare entity in colonic diverticular disease and is characterized by a high rate of complications such as perforation, abscess formation and even carcinoma. We report a case of a complicated giant diverticulum of the transverse colon accompanied by a right inguinal hernia of the greater omentum in a 52-year-old man, as demonstrated on CT.

The increase in hepatic uncoupling by fenofibrate contributes to a decrease in adipose tissue in obese rats

Fenofibrate is a drug that has been suggested to inhibit weight gain by increasing the catabolism of fatty acid in the hepatic mitochondria. We hypothesized that fenofibrate induces an increase in energy expenditure in the hepatic mitochondria, which results in the reduction of adipose tissue. In this study we measured hepatic uncoupling protein (UCP)-2, -3, core temperatures and abdominal fat composition with MRI in Otsuka Long-Evans Tokushima Fatty rats. The fenofibrate group (n=7) was fed fenofibrate (320 mg/kg) mixed chow. The control group (n=7) was fed chow only. The body weight (531.6+/-7.6 g) of the fenofibrate group was significantly lower than that (744.3+/-14.9 g) of the control group (p<0.005). The areas of visceral and subcutaneous fat in the fenofibrate group (11.0+/-0.9 cm(2), 4.2+/-0.3 cm(2)) were significantly less than those in the control group (21.0+/-0.7 cm(2), 7.4+/-0.4 cm(2)) (p=0.046, respectively). The esophageal and rectal temperatures of the fenofibrate group (37.7+/-0.1 degrees C, 33.1+/-0.2 degrees C) were significantly higher than those of the control group (37.3+/-0.1 degrees C, 32.2+/-0.1 degrees C) (p=0.025, p=0.005). There was de novo expression of UCP-3 in the liver of the fenofibrate group. These data suggest that increased energy dissipation, via hepatic UCP-3 by fenofibrate, contribute to decreased weight gain in obese rats.

Dual reporter genes enabling cell tracing with viable and reliable selection of various cell types

Dual reporter genes driven by either a ubiquitous cytomegalovirus (CMV) or a neuro-specific tubulin alpha1 promoter (Talpha1) were constructed. The new genes, CMV (pCMV-GL) or Talpha1 promoter-driven GFP-LacZ (pTalpha1-GL), robustly expressed the fused GFP-LacZ protein reporting constitutive expressions in various cell types including CHO cells, loach and chicken embryos, and neuro-specific expression in differentiating mouse embryonic stem cells, respectively. The dual reporter genes thus provide a versatile tool for the studies of gene expression, cell lineage within the embryo and possibly the fate of stem cells in transplantation experiment, thus facilitating different analyses depending on the experimental purposes.

Effects of Lactobacillus strains on cancer cell proliferation and oxidative stress in vitro

AIMS

The objective of this study was to assess in vitro, whether heat-killed (HK) lactic acid bacteria cells and fractionations of HK cells could suppress the viability of human cancer cells and inhibit the cytotoxicity associated with oxidative stress.

METHODS AND RESULTS

Among the strains, the HK cells of Lactobacillus acidophilus 606 and Lactobacillus casei ATCC 393 exhibited the most profound inhibitory activity in all of the tested cell lines. HK cells of L. acidophilus 606 were determined to be less toxic to healthy human embryo fibroblasts (hEF cells) than were HK cells of L. casei ATCC 393. The soluble polysaccharides from L. acidophilus 606 evidenced the most effective anticancer activity, but inhibited hEF cell growth by only 20%. The soluble polysaccharides from L. acidophilus 606 were partly observed to induce apoptosis in the HT-29 cells by DNA fragmentation and propidium iodine staining. Both the HK cells of L. acidophilus 606 and the soluble polysaccharide components of this strain also exhibited potent antioxidative activity.

CONCLUSIONS

Our findings suggest that the soluble polysaccharide fraction from L. acidophilus 606 may constitute a novel anticancer agent, which manifests a high degree of selectivity for human cancer cells and antioxidative agent in the food industry.

SIGNIFICANCE AND IMPACT OF THE STUDY

These soluble polysaccharide components from Lactobacillus may be applied to various foods, and used as adjuncts for cancer therapy and prevention.

Comparison between high and low molecular weight hyaluronates in knee osteoarthritis patients: open-label, randomized, multicentre clinical trial

Efficacy and safety of high and low molecular weight hyaluronates in knee osteoarthritis patients were compared in a randomized, open-label trial. Patients in the high molecular weight hyaluronate group were treated once weekly for 3 weeks and in the low molecular weight group once weekly for 5 weeks. We evaluated weight-bearing pain, degree of flexion, swelling and knee tenderness; frequency and amount of rescue medication; patient and investigator global assessment of pain, and safety over 12 weeks after final injection of study medication. Significant improvements in pain and WOMAC-Likert scores were observed in both groups, but not between groups. Knee joint pain improvement was noted in both groups by patients and investigators during follow-up. Close correlation was observed between patient- and investigator-reported data. There was no significant difference in side-effects between the groups. In conclusion, the efficacy and safety of high and low molecular weight hyaluronate are similar.

Antitumor activity of TRAIL recombinant adenovirus in human malignant glioma cells

Tumor necrosis factor-Related Apoptosis-Inducing Ligand (TRAIL) has been reported to specifically kill malignant cells but to be relatively nontoxic to normal cells. One of disadvantages to previous in vivo protocols was the need for large quantities of TRAIL recombinant protein to suppress tumor growth. To evaluate the antitumor activity and therapeutic value of the TRAIL gene, we constructed adenoviral vectors expressing the human TRAIL gene (Ad.hTRAIL) and transferred them into malignant glioma cells in vitro and tumors in vivo, as an alternative to recombinant soluble TRAIL protein. The results show that TRAIL-sensitive glioma cells infected Ad.hTRAIL undergo apoptosis through the production and expression of TRAIL protein. The in vitro transfer elicited apoptosis, as demonstrated by the quantification of viable or apoptotic cells and by the analysis of cleavage of poly (ADP-ribose) polymerase. Furthermore, in vivo administration of Ad.hTRAIL at the site of tumor implantation suppressed the outgrowth of human glioma xenografts in SCID mice. These results further define Ad.hTRAIL as an anti-tumor therapeutic and demonstrate its potential use as an alternative approach to treatment for malignant glioma.

Coronary artery spasm induced by carotid sinus stimulation during neck surgery

We observed four transient episodes of marked ST-segment elevation in a 58-yr-old man with no history of coronary artery disease undergoing resection of a metastatic neck mass under general anaesthesia. Elevations of the ST segment were abrupt, with no change in arterial pressure or heart rate, and resolved spontaneously. When the carotid sinus was compressed directly, ST-segment elevation was noted 1 min after the onset of stimulation. After surgery, coronary angiography showed diffuse, slight narrowing of the distal bed of the posterolateral branch of the right coronary artery. Ergonovine caused total occlusion of the posterolateral branch of the right coronary artery with chest pain and ST-segment elevation, confirming the diagnosis of variant angina. The coronary artery spasm seems to have been provoked by vagal activation from carotid sinus stimulation during general anaesthesia.

Fenofibrate lowers abdominal and skeletal adiposity and improves insulin sensitivity in OLETF rats

The effect of peroxisome proliferator-activated receptor (PPAR)-alpha activators on the liver is well established, but the other effects on muscle and adipose tissue about lipid metabolism and insulin sensitivity are not clear. We investigated whether PPAR-alpha activation affects adiposity of skeletal muscle as well as adipose tissue and improves insulin sensitivity in spontaneous type 2 diabetes model, Otsuka Long-Evans Tokushima Fatty (OLETF) rats. Thirty-three weeks of aged, 20 male OLETF rats were divided into two groups. Control group (n=10) was fed with chow and treatment group (n=10) with chow contained fenofibrate for 7 weeks. At the age of 40 weeks, all rats were examined with MRI, intravenous glucose tolerance test, and then sacrificed for measurement of fat mass and RNA analyses. The total fat (the sum of subcutaneous, mesenteric, epididymal, and retroperitoneal fat pads) measured by dissection was significantly reduced in treatment group. The signal intensity of muscular adiposity was significantly decreased in treatment group. The mRNA levels of FAT/CD36 and mitochondrial carnitine palmitoyltransferase I (M-CPT I) in liver were remarkably increased. Fasting plasma insulin and leptin levels, insulin response after intravenous glucose loading and homeostasis model assessment insulin resistance (HOMA(IR)) index were lowered in treatment group. Fenofibrate increase mitochondrial fatty acid beta-oxidation in liver but not in skeletal muscle and lower the plasma levels of triglyceride and free fatty acid. It might result in reduction of adiposity of truncal adipose tissue and skeletal muscle. We suggest that reduction of adiposity in trunk and skeletal muscle might improve insulin sensitivity.

Antinociceptive profiles of aspirin and acetaminophen in formalin, substance P and glutamate pain models

Aspirin (ASA) is widely used oral analgesics and acts as an inhibitor of cyclo-oxygenase. Also, acetaminophen (APAP) is effective analgesics and may selectively inhibit brain prostaglandin synthetase. However, their mechanisms of action in CNS are poorly defined, although several authors have shown that the antinociceptive effects of ASA and APAP have different underlying mechanisms and play some possible roles on spinal nociceptive processing, such as inhibition of prostaglandin synthesis. To define and characterize antinociceptive profiles of ASA and APAP on various pain models, we performed intraplantar formalin injection test, intrathecal (i.t.) substance P (0.7 microg)-induced nociceptive response test, and i.t. glutamate (20 microg)-induced nociceptive response test after ASA or APAP (from 10 to 300 mg/kg) administered orally to the mouse. In the formalin test, ASA produced an antinociceptive effect during only the 2nd phase (20-40 min), but not the 1st phase (0-5 min), in a dose-dependent manner. However, APAP showed a dose-dependent antinociceptive effect during both phases of the formalin test. In addition, both ASA and APAP reduced nociceptive behavior induced by glutamate administered i.t. in a dose-dependent manner. In substance P-induced nociceptive response, APAP, but not ASA, showed antinociceptive effect in a dose-dependent manner. Our results suggest that ASA and APAP administered orally may be mediated by different nociceptive processing at the spinal cord level.

Short term surgical outcomes of modified deep sclerectomy with catgut implant

We compared the effectiveness of and complications resulting from modified deep sclerectomy with catgut implant (modified-DSCI) with those of standard deep sclerectomy with collagen implant (DSCI) in the short term following surgery. In this retrospective study, standard-DSCI was performed on thirteen patients (17 eyes), and modified-DSCI was performed on seven patients (11 eyes). After dissection of a 5x5 mm sized superficial scleral flap, a 3x4 mm sized rectangular deep scleral flap was constructed in DSCI and a 2x3 mm sized triangular deep scleral flap in modified DSCI. A collagen implant was placed on the scleral bed in DSCI and # 0 CHROMIC Catgut Absorbable Suture was used in modified DSCI. The mean follow up was 11.0+/-6.1 months in DSCI and 9.3+/-4.7 months in modified DSCI. The mean preoperative intraocular pressure (IOP) was 38.6+/-10.9 mmHg in DSCI and 34.8+/-8.6 mmHg in modified DSCI. In the DSCI group, the IOP was 13.4+/-3.0 mmHg at final follow up, and was 11.4+/-3.2 mmHg in the modified DSCI group. The number of Nd:YAG goniopuncture was 3 cases (25%) in the modified DSCI group, and 3 cases (21.4%) in the DSCI group. The number of intraoperative microperforations was 3 in the DSCI group and 2 in the modified DSCI group. Temporary hypotony was encountered in 8 eyes (57.1%) of the DSCI group and 4 eyes (50%) of the modified DSCI group. There was no significant difference observed between the two groups in regards to the effectiveness or rate of complications seen during short term follow up.

Enhanced urinalysis improves identification of febrile infants ages 60 days and younger at low risk for serious bacterial illness

OBJECTIVE

Investigators have sought to establish "low-risk" criteria to identify febrile young infants who can be observed safely without antibiotics. Previous studies have used criteria for standard urinalysis to identify suspected urinary tract infection; however, cases of urinary tract infection have been missed. Enhanced urinalysis, using hemocytometer cell count and Gram stain performed on uncentrifuged urine, has been shown to have greater sensitivity and negative predictive value than standard urinalysis. The objective of this study was to evaluate the ability of criteria that incorporate enhanced urinalysis to identify febrile young infants who are at low risk for serious bacterial illness (SBI).

METHODS

Institutional guidelines were established in 1999 to evaluate in a retrospective cohort study infants who were </=60 days of age with temperature >/=38.0 degrees C. "Low-risk" criteria included 1) well appearance without focal infection (excluding otitis media); 2) no history of prematurity, illness, or previous antibiotics; 3) peripheral white blood cell count (WBC) between 5 and 15 000/mm(3); 4) absolute band count </=1500/mm(3); 5) cerebrospinal fluid WBC </=5/mm(3) with a negative Gram stain; 6) enhanced urinalysis with WBC </=9/mm(3) with a negative Gram stain; 7) stool WBC <5/high power field in infants with diarrhea; and 8) chest radiograph without lobar infiltrate(s) in infants with respiratory signs or symptoms. SBI was defined as a lobar infiltrate on chest radiograph or presence of a bacterial pathogen in blood, urine, cerebrospinal fluid, stool, or culture obtained from the soft tissue. The hospital records of all infants who presented to the emergency department for evaluation of fever after January 1999, including those who did not meet low-risk criteria, were reviewed; data were collected regarding history, physical examination, laboratory test results, treatment, and clinical course.

RESULTS

During the study period, 434 infants presented to the emergency department for evaluation of fever. Thirty patients were excluded from additional analysis because of incomplete data; 60 patients were identified immediately as "not low risk" on the basis of history or physical examination. Of the 344 remaining infants, 127 were identified as "low risk" on the basis of laboratory criteria; 83 (65.4%) were observed without antibiotics. None of the "low-risk" infants had an SBI. A total of 217 well-appearing infants were classified as "not low risk" on the basis of laboratory criteria; 28 (12.9%) had an SBI. The overall incidence of SBI in infants with complete data was 10.1%, whereas the incidence of SBI in all "not low-risk" infants was 14.8%. The negative predictive value for the "Pittsburgh" criteria was 100% (95% confidence interval: 96.7%-100%); the sensitivity was 100% (95% confidence interval: 89.7%-100%).

CONCLUSIONS

. The application of low-risk criteria using enhanced urinalysis improves identification of infants who are at low risk for SBI.

A case of glaucoma associated with Sturge-Weber syndrome and Nevus of Ota

The Sturge-Weber syndrome consists of a unilateral port-wine hemangioma of the skin along the trigeminal distribution and is accompanied by an ipsilateral leptomeningeal angioma. Glaucoma is present in approximately half of the cases. The Nevus of Ota is a melanocytic pigmentary disorder, most commonly involving the area innervated by the trigeminal nerve. Elevated intraocular pressure, with or without glaucomatous damage, is observed in 10% of the cases. We report the first case of glaucoma associated with Sturge-Weber syndrome and Nevus of Ota in Korea.

The effect of intranasal fentanyl on the emergence characteristics after sevoflurane anesthesia in children undergoing surgery for bilateral myringotomy tube placement

Children undergoing placement of bilateral myringotomy tubes (BMT) often exhibit pain-related behavior (agitation) in the postanesthesia care unit. We compared the emergence and recovery profiles of pediatric patients who received sevoflurane with or without supplementary intranasal fentanyl for BMT surgery. By using a prospective, double-blinded design, 150 children 6 mo to 5 yr of age, scheduled for routine BMT surgery, were anesthetized with sevoflurane (2%-3%) in a 60% N(2)O/O(2) gas mixture. Patients were randomized to receive equal volumes of intranasal saline (Control), 1 microg/kg fentanyl or 2 microg/kg fentanyl. A blinded observer evaluated each patient using a previously described 4-point agitation scale and the Steward recovery scale. Response to parental presence was observed after a score of six (full recovery) was achieved on the Steward recovery scale. There were no significant differences among the three groups regarding age, weight, surgeon, duration of anesthesia, or ear condition. Recovery times and emergence characteristic scores were not statistically different. Agitation scores were significantly reduced in the 2-microg/kg Fentanyl group as compared with the Control group (P = 0.012). Fentanyl 2 microg/kg is recommended to reduce the incidence of agitation seen in these patients.

IMPLICATIONS

We examined the use of nasally administered fentanyl for the relief of agitation or discomfort after placement of bilateral myringotomy tubes in 150 children ages 6 mo to 5 yr using a prospective, double-blinded design. Fentanyl 2 microg/kg was found to reduce the incidence of agitation in these patients.

Possible roles of JNK pathway in the regulation of hippocampal proenkephalin and immediate early gene expression induced by kainic acid

Mitogen-activated protein kinases (MAPKs) may play crucial roles in the kainic acid (KA)-evoked excitotoxic effect and the regulation of transcription factors (e.g. c-Fos and c-Jun) in hippocampus, but their exact role in the regulation of KA-induced opioid peptides expression has not been well characterized in vivo. Therefore, we examined possible involvement of the phosphorylated form of JNK, as well as CREB, in the regulation of KA-induced proenkephalin and immediate early genes (IEGs) expression in the rat hippocampus. KA increased proenkephalin mRNA expression in rat hippocampus, which was decreased by pre-administration with cycloheximide (CHX, a protein synthesis inhibitor). KA alone increased c-fos as well as c-jun mRNA levels. CHX further enhanced KA-induced c-fos and c-jun mRNA levels. Additionally, KA increased the phosphorylation of JNK, especially JNK1, which was attenuated by CHX. CHX decreased KA-induced c-Fos protein expression. Interestingly, CHX itself increased the phosphorylation of CREB, which was abolished by KA administration. Our results suggest that the phosphorylation of JNK is involved in the up-regulation of the proenkephalin gene expression via c-Fos and c-Jun that is induced by KA in rat hippocampus. However, the phosphorylation of CREB is not associated with the up-regulation of the proenkephalin mRNA level induced by KA in the rat hippocampus.

Differential roles of spinal cholera toxin- and pertussis toxin-sensitive G proteins in nociceptive responses caused by formalin, capsaicin, and substance P in mice

The aim of the present study is to characterize the roles of spinal cholera toxin (CTX)- and pertussis toxin (PTX)-sensitive G proteins in the regulation of various nociceptive responses. The effects of intrathecal (i.t.) pretreatments with CTX and PTX on the formalin (subcutaneous)-, capsaicin (i.t.)-, and substance P (SP; i.t.)-induced nociceptive behaviours were examined in mice. Pretreatment with CTX (i.t.; 24 h before) significantly and dose-dependently (0.05-0.5 microg) suppressed both the first and second phases of the formalin-induced nociceptive behaviour. On the other hand, pretreatment with PTX (i.t., 6 days before) at the same doses (0.05-N0.5 microg) did not affect the formalin-induced response. Capsaicin (i.t., 0.5 microg)- and SP (i.t., 0.7 microg)-induced nociceptive behaviours were attenuated by the pretreatment with CTX. In addition, SP-induced nociceptive response was also attenuated by the pretreatment with PTX. However, the capsaicin-induced nociceptive response was not influenced by PTX pretreatment. These findings suggest that, at the spinal cord level, CTX-sensitive G-proteins are involved in the formalin-, capsaicin-, and SP-induced nociceptive behavioural responses, whereas PTX-sensitive G proteins are involved in SP-induced nociceptive response.

Production and secretion patterns of cloned glucoamylase in plasmid-harboring and chromosome-integrated recombinant yeasts employing an SUC2 promoter

To understand the differences in production and secretion patterns between plasmid-harboring and chromosome-integrated recombinant yeasts, the two recombinant Saccharomyces cerevisiae yeasts, containing the structural glucoamylase STA gene and the SUC2 promoter, were investigated. Both systems were regulated by glucose concentration in the culture broth. First, the glucoamylase activity per gene copy number of the chromosome-integrated recombinant yeast was 2.8- to 5.6-fold higher than that of the plasmid-harboring recombinant yeast. Overburdened owing to high copy number, the plasmid-harboring recombinant yeast gave lower glucoamylase activity per gene copy number. Second, the efficiency of signal sequence was compared; the secretion efficiency of glucoamylase in the plasmid-harboring recombinant yeast was higher than that in the chromosome-integrated recombinant yeast at 96 h of cultivation (74 vs 65%). We postulated that the higher level of secretion efficiency of the plasmid-harboring recombinant yeast resulted because the production level did not reach the capacity of the secretory apparatus of the host yeast. However, the specific secretion rate was much higher in the chromosome-integrated recombinant yeast even though the final secretion efficiency was lower. The lower secretion rate in the plasmid-harboring recombinant yeast could be explained by an adverse effect caused by higher production rate. Finally, the optimal glucose concentration for glucoamylase production in the chromosome-integrated recombinant yeast culture was lower than that in the plasmid-harboring recombinant yeast culture owing to gene dosage effect.

Purification and characterization of a highly stable tyrosinase from Thermomicrobium roseum

Tyrosinase, with an isoelectric point at pH 4.9, was purified to electrophoretic homogeneity from an extremely thermophilic bacterium, Thermomicrobium roseum. Gel filtration, N-terminal amino acid sequencing and SDS/PAGE analysis indicate that T. roseum tyrosinase is composed of two identical subunits, each with a molecular mass of 43000 Da. The enzyme exhibited high substrate specificity towards catechol, chlorogenic acid, L-3-(3,4-dihydroxyphenyl)-L-alanine (L-DOPA) and pyrogallol. The K(m) value of the enzyme for L-DOPA was 0.18 mM. beta-Mercaptoethanol and sodium diethyldithiocarbamate notably inhibited the enzymic activity. The activity of the enzyme was optimal at pH 9.5 and 70 degrees C, and was increased by addition of 1 mM Mg(2+), K(+) or Cu(2+). The enzyme was highly stable against high temperature and guanidine hydrochloride. The N-terminal amino acid sequence of the enzyme was determined to be Asp-Ile-Asn-Gly-Gly-Gly-Ala-Thr-Leu-Pro-Gln-Lys-Leu-Tyr. These facts indicate that T. roseum tyrosinase appears to be distinct from the tyrosinases so far purified from other sources.

Postsurgical follow-up of children with tympanostomy tubes: results of the American Academy of Otolaryngology-Head and Neck Surgery Pediatric Otolaryngology Committee National Survey

Postsurgical follow-up of children with tympanostomy tubes is becoming a contentious issue in this era of managed care. Primary care providers believe themselves to be capable of evaluating these children. Otolaryngologists, on the other hand, have more specialized equipment available to them (suction apparatus, otomicroscopes, audiology devices, etc) for treating suppurative infections and monitoring the tympanic membrane for structural changes. In addition, the otolaryngologist is placed in an uncomfortable legal and ethical position if access to the patient with a tube-related complication is denied by the primary care provider. Attempts to develop an American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS) policy statement have been hampered by a lack of data on the incidence and severity of tube-related complications and the role that otolaryngologists can play in reducing these sequelae. A survey designed by the AAO-HNS Pediatric Otolaryngology Committee was distributed to 1000 board-certified otolaryngologists and all members of the American Society of Pediatric Otolaryngologists and the American Academy of Pediatrics-Otolaryngology Section regarding current practice patterns and practitioners' experiences with tympanostomy tube complications. Specific information regarding complications that could have been avoided with earlier otolaryngology referral was also obtained. The results of the survey and its implications for AAO-HNS policy are presented.

Changing trends in neonatal subglottic stenosis

OBJECTIVES

To determine whether there are any changes in the incidence and management of neonatal subglottic stenosis (SGS).

METHODS

A retrospective chart review of 416 infants who were admitted to the neonatal intensive care unit of the Children's National Medical Center between July 1, 1995, and June 30, 1996, was carried out. The incidence of airway obstruction requiring anterior cricoid split or placement of tracheotomy tube was determined and compared with the incidence studied 10 years ago at the same institution.

RESULTS

One of 416 neonates required surgical intervention for airway obstruction caused by SGS, for an overall neonatal SGS incidence of 0.24%. When only the neonates who were intubated for 48 hours or longer were considered, the incidence of SGS was 0.49% (1/204). In neonates who were intubated for 48 hours or longer and survived, the incidence of SGS was 0.63% (1/160). This is in comparison with the incidences of 0.65% (3/462), 1.5% (3/195), and 1.9% (3/159), respectively, seen in a study done at the Children's National Medical Center 10 years ago. Five infants in this current study required placement of a tracheotomy tube for reasons other than SGS. Two infants needed tracheotomy tube placement for micrognathia, and 3 others for central hypotonia, an omphalocele that required multiple surgical procedures, and choanal atresia with a serious heart anomaly, which was a manifestation of CHARGE association. None of these 5 infants had evidence of SGS at rigid endoscopy preceding the tracheotomy tube placement.

CONCLUSION

The incidence and management of neonatal SGS remain unchanged during this study period when compared with those of 10 years ago.

Airway abnormalities in patients with Arnold-Chiari malformation

OBJECTIVES

The goal was to determine the incidence and types of airway abnormalities in patients with Arnold-Chiari malformation (ACM).

METHODS

The study was a retrospective chart review of 24 patients with ACM who were evaluated and treated between November 1991 and August 1997.

RESULTS

Eighteen (75%) and 6 (25%) of the 24 patients had types I and II ACM, respectively. Three (12.5% of 24 patients) of the type II ACM patients had vocal cord impairment: 1 bilateral paralysis, 1 bilateral paresis, and 1 unilateral paralysis. None of the type I ACM patients had vocal cord impairment. Tracheotomy was necessary in 3 of the 24 patients and all in patients with type II ACM. Central sleep apnea was found in 5 of 6 type II ACM patients, but not in any of the type I ACM patients.

CONCLUSIONS

Vocal cord impairment and sleep apnea were found in 12. 5% and 21%, respectively, of this ACM population. When type II ACM patients were considered separately, the incidences of vocal cord impairment and sleep apnea were 50% and 83%, respectively. Type II ACM patients tend to have a higher incidence of airway abnormalities and other neurologic dysfunctions. Flexible fiberoptic laryngoscopy is recommended in the airway evaluation of ACM patients. Early recognition, diagnosis, and management of these abnormalities may be lifesaving.

Chromosomal localization of ESTs obtained from human fetal liver via BAC-mediated FISH mapping

A total of 55 expressed sequence tags (ESTs) randomly chosen from our collection of fetal liver ESTs were mapped to chromosomes by fluorescence in situ hybridization (FISH) mapping techniques. To generate FISH mapping probes, the genomic DNAs for each EST were selected by screening an arrayed human bacterial artificial chromosome (BAC) library. In total, 73 BACs were used for mapping of the 55 ESTs. Among them, 70 BACs representing 52 ESTs unequivocally mapped to single chromosomal regions. The remaining 3 BACs representing 3 ESTs were localized to multiple regions, suggesting that BACs may have very low chimerism. Our mapping results were compared with EST mapping databases deposited in NCBI. Thirty-six of 55 ESTs corresponded to previously mapped positions of ESTs, 2 ESTs mapped to different positions from previously determined ones, and it was found that 17 ESTs have been mapped on new locations from this study. These mapping data may be used for completing the framework of the human physical map, and also for providing a good starting point for searching disease-related genes.

Pitfalls in laryngotracheal reconstruction

OBJECTIVE

To determine the causes of laryngotracheal reconstruction (LTR) failures.

DESIGN

Retrospective chart review.

SETTING

Tertiary care children's hospital.

PATIENTS

Seventeen pediatric patients who underwent revision LTR from October 1, 1986, to December 31, 1998.

INTERVENTION

Laryngotracheal reconstruction.

MAIN OUTCOME MEASURE

Decannulation.

RESULTS

Seventeen patients required a total of 42 LTRs for decannulation. There were 17 primary LTRs and 25 revision LTRs. The primary LTRs were done either at our or other institutions. Two patients died after initial LTR failed, one because of tracheotomy tube plugging and the other because of a severe respiratory syncytial virus pneumonia. All 15 remaining patients have been decannulated. There were 27 failed LTRs with 17 being primary and 10 revision LTR failures. In 3 of the 27 failed procedures, no obvious causes for failure could be found. In the remaining 24 procedures, 1 or more factors that contributed to LTR failure could be found. Poor preoperative evaluation with subsequent failure to address the airway lesion was seen in 6 procedures. Intraoperative reasons for LTR failure included inappropriate choice of graft in 2 procedures; inappropriate stent in 7; inappropriate stent length in 1; and inappropriate duration of stent in 8. In 6 procedures, the airway abnormalities identified at endoscopy were not adequately addressed at LTR. Postoperative factors for failure were poor follow-up in 2, anterior suprastomal collapse in 2, and slipped or broken stent in 2. Other factors that contributed to LTR failures included intractable gastroesophageal reflux disease in 1 procedure and keloid formation in 5.

CONCLUSIONS

Although some LTRs may fail secondary to factors that are not under the surgeon's control, many LTR failures can be avoided by accurate preoperative and intraoperative assessment of the stenosis, correct choice of surgical procedure, and close postoperative monitoring.

Characteristics of the intracavity dispersion in an erbium-doped fiber laser

We have found theoretically that the intracavity dispersion of a laser is independent of the pumping power and wavelength and that the resonant group-velocity dispersion vanishes. We have experimentally observed that the intracavity dispersion of an erbium-doped fiber laser was independent of the pumping power and wavelength within the measuring error, which agrees well with our theoretical predictions.

Clinical applications of transiently evoked otoacoustic emissions in the pediatric population

Our objectives were 1) to determine whether transiently evoked otoacoustic emissions (TEOAEs) are affected by the status of the tympanic membrane (TM) and middle ear (ME) as determined by clinical examinations and tympanograms; 2) to determine the efficacy of TEOAEs in detecting hearing loss; and 3) to determine the relative effects of the ME status and hearing loss on TEOAEs. In a prospective observational study in a tertiary care children's hospital, 89 patients (169 ears; 9 ears eliminated from analyses) were examined by 2 attending pediatric otolaryngologists for otologic conditions and underwent audiologic evaluations including TEOAEs from August 1994 through May 1995. The main outcome measures were presence or absence of TEOAE whole reproducibility (WR) and reproducibility (R) at 2 kHz. Statistical analyses showed that of the 8 ME and TM conditions evaluated (normal, TM perforation, pressure equalization [PE] tube, TM retraction, tympanosclerosis, TM atrophy, ME effusion, surgery other than PE tube insertion), only the presence of ME effusion and normal examination findings had a significant effect on the results of WR and R at 2 kHz. Of the 6 different types of tympanograms evaluated (A, B, C, AD, As, B with large volume), type A, B, and C tympanograms had a significant effect on WR and types A and B had a significant effect on R at 2 kHz. Hearing losses > or = 25 dB hearing level (HL) at any of the 5 frequencies (0.25, 0.5, 1, 2, and 4 kHz) were well predicted by the absence of WR and R at 2 kHz. When clinical examination and impedance data were evaluated simultaneously with hearing status, hearing status had a greater effect on WR and R at 2 kHz. We conclude that type B and C tympanograms and the presence of ME effusion (which reflect abnormal ME status) have an adverse effect on TEOAEs. However, the presence of hearing loss is the most significant predictor of TEOAE results. The TEOAE WR and R at 2 kHz are effective in identifying patients with normal hearing and with hearing losses > or = 25 dB HL.

Expression of Bfl-1 in normal and tumor tissues: Bfl-1 overexpression in cancer is attributable to its preferential expression in infiltrating inflammatory cells

Bfl-1, a member of the Bcl-2 gene family, blocks p53-mediated apoptosis and has oncogenic transforming activity. In normal tissues, the transcript of Bfl-1 is expressed abundantly in bone marrow and at a low level in several other tissues. In previous experiments, elevated expression of Bfl-1 was observed by Northern analysis of stomach cancer samples. To study the role of Bfl-1 in normal cell development and in tumorigenesis, we have analyzed the expression of Bfl-1 in normal and tumor tissues by the in situ hybridization technique. The Bfl-1 transcript was detected in the white pulp of the spleen and in the germinal center of lymphatic tissues. In tumor tissues, its expression was preferentially detected in infiltrating inflammatory cells rather than in cancer cells, suggesting that Bfl-1 is not involved in tumorigenesis.

Dynamic-strain measurement with dual-grating fiber sensor

A dual-grating sensor head, which was designed for temperature-insensitive strain measurement, was used to measure fast-varying strain perturbations. Using a Mach-Zehnder interferometer technique, we obtained ~0.1-muepsilon (microstrain) rms resolution with a 200-Hz strain input. The feasibility of measuring a dynamic-strain with a static-strain measuring configuration was also demonstrated.

Efficient Single-Mode GaAs/AlGaAs W Waveguide Phase Modulator with a Low Propagation Loss

We report a single-mode P-P-p-i-n-N-N GaAs/AlGaAs W waveguide phase modulator with a high phase modulation efficiency and a low propagation loss. The phase modulator with a W-shaped refractive-index profile utilizes a novel epilayer structure to reduce the propagation loss associated with doped layers and to obtain a phase modulation efficiency larger than those of P-i-N double heterostructure modulators. The phase shift and propagation loss were measured with a Fabry-Perot resonance method at 1.31-mum wavelength. A phase modulation efficiency as high as 34.6 degrees /V mm was measured for TE polarized light. Also propagation losses of less than 0.6 dB/cm were achieved. As a result, the W waveguide phase modulator that exhibits a high phase modulation efficiency and a low propagation loss have been experimentally realized for the first time as far as we know.

Displacements of the resonant peaks of a long-period fiber grating induced by a change of ambient refractive index

We present a graphic method of analyzing the spectral displacements of a long-period fiber grating as a function of ambient index. Mode dependence of the maximum displacement, disappearance of a particular resonance peak, and spectral behavior when the ambient index is larger than that of the cladding material are investigated and compared with experimental results.

Relative incidence and alternative approaches for surgical drainage of different types of deep neck abscesses in children

OBJECTIVES

To determine the relative frequency of retropharyngeal abscesses (RPAs) vs lateral pharyngeal abscesses (LPAs) and to analyze alternative approaches for surgical drainage.

DESIGN

Retrospective chart review.

SETTING

Tertiary care children's hospital.

PATIENTS

Seventy pediatric patients who were evaluated, admitted, and treated for presumed deep neck abscesses (RPAs and LPAs) between January 1, 1986, and December 31, 1996.

INTERVENTION

Intravenous antibiotic therapy and surgical drainage.

MAIN OUTCOME MEASURE

Clinical resolution of the abscess.

RESULTS

Fifty-eight patients were evaluated with computed tomographic scan. Thirteen of these patients did not have surgical intervention. Of 12 patients diagnosed as having an isolated RPA, all had intraoral surgical drainage and 9 had evidence of pus at surgery. Twenty-one patients had an isolated LPA. Sixteen of these underwent intraoral drainage and 5 underwent external drainage. Purulence was found at surgery in 14 and 2 patients, respectively. The remaining 12 patients had a combination of RPA and LPA. Eight patients underwent intraoral drainage, and 4 patients required both intraoral and external approaches. Purulence was found at surgery in 5 and 4 patients, respectively. Of the 12 patients who were not evaluated with computed tomographic scan, two thirds were treated prior to 1987. Six of these 12 patients underwent surgical drainage via an intraoral approach, and 4 of the 6 patients had pus. The remaining 6 improved without surgery.

CONCLUSIONS

Most deep neck abscesses in children are located in the retropharyngeal or in the lateral pharyngeal space medial to the great vessels. Therefore, most can be managed successfully with intraoral rather than external drainage. External approaches are better reserved for those abscesses that are lateral to the great vessels or that involve multiple spaces. In this patient population, LPAs were more commonly seen than RPAs.

Management of oropharyngeal trauma in children

OBJECTIVE

To determine the indications for admission, requisite imaging studies, and urgent medical or surgical intervention.

DESIGN

We retrospectively reviewed the charts of 26 children (age range, 5 months to 14 years) who were seen by the otolaryngology service in the emergency department at the Children's National Medical Center, Washington, DC, from 1985 to 1993 and who were diagnosed as having oropharyngeal trauma. We specifically looked for common findings in the history and physical examination on initial presentation to predict the necessary steps in evaluation and management.

SETTING

Tertiary care pediatric referral center.

RESULTS

Indications for admission were (1) concern about neurologic injury, (2) concern about vascular injury, (3) radiographic evidence of retropharyngeal free air or abscess, (4) pneumomediastinum, and (5) unreliable adult supervision at home. Six patients required surgery; 3 underwent retropharyngeal aspiration or incision and drainage procedures; 2 required neck explorations; and 1, who had an impaled foreign body in the parapharyngeal space, underwent surgical extraction. There were no vascular, neurologic, or other permanent injuries.

CONCLUSIONS

Oropharyngeal trauma may result in palatal and posterior pharyngeal wall injury requiring closure of lacerations and management of retropharyngeal free air. Rarely does an injury lead to retropharyngeal abscess or significant pneumomediastinum. Lateral oropharyngeal injuries require increased concern about potential neurovascular impairment. However, neither the mechanism of injury nor the degree of injury correlates with the potential for neurovascular sequelae. Since neurovascular involvement may not become clinically apparent until days or weeks after the incident, admission for observation alone should be based on the distance from the patient's home to the hospital and on the level of reliable adult supervision. Indications for medical and surgical treatment of internal carotid artery thrombosis remain controversial.

Expression of a novel Bcl-2 related gene, Bfl-1, in various human cancers and cancer cell lines

The expression of Bfl-1 gene, a novel Bcl-2 related gene, was determined by Northern blot analysis using a radiolabeled cDNA specific for Bfl-1 gene in 82 surgically resected tissue specimens of 28 gastric cancers, 15 colon cancers, nine breast cancers, eight bone and soft tissue sarcomas, five ovarian cancers, nine colon adenomas and eight gastric adenomas. A high rate of expression was observed in gastric and colon cancer, at 86 and 93%, respectively. In breast cancer, bone and soft tissue sarcoma and ovarian cancer, the expression rate was 33, 25 and 40%, respectively. In stomach cancer, the expression rate of Bfl-1 gene in metastatic lymph nodes was 82%, which was higher than 50% of the primary sites (p < 0.02). The intensity of RNA bands of the gastric cancer specimens was compared according to the stage, demonstrating that there was no difference in the expression levels of Bfl-1 gene between the stages in both primary sites and metastatic lymph nodes. Bfl-1 gene was expressed in three (33%) out of nine adenomas of the colon, while it was not detected in all eight gastric adenomas, We also examined the RNA expression of Bfl-1 gene in 22 human cancer cell lines consisting of five stomach cancer, four squamous cell carcinoma, three lung cancer, three cervical cancer, two colon cancer, two brain cancer, two leukemia and one osteosarcoma cell lines. Bfl-1 gene band was detected in one (5%) cervical cancer cell line, SiHa. The results of cancer tissue specimens indicate that Bfl-1 gene may play an important role in carcinogenesis of human cancers and may be involved in a relatively early phase of the adenoma-carcinoma sequence in colon cancer development. However, the mechanism responsible for the very low rate of expression in established cell lines is not clearly understood and further investigation is necessary to clarify the mechanism involved.