Head-to-head comparison of [18F]-Flortaucipir, [18F]-MK-6240 and [18F]-PI-2620 postmortem binding across the spectrum of neurodegenerative diseases

We and others have shown that [18F]-Flortaucipir, the most validated tau PET tracer thus far, binds with strong affinity to tau aggregates in Alzheimer's (AD) but has relatively low affinity for tau aggregates in non-AD tauopathies and exhibits off-target binding to neuromelanin- and melanin-containing cells, and to hemorrhages. Several second-generation tau tracers have been subsequently developed. [18F]-MK-6240 and [18F]-PI-2620 are the two that have garnered most attention. Our recent data indicated that the binding pattern of [18F]-MK-6240 closely parallels that of [18F]-Flortaucipir. The present study aimed at the direct comparison of the autoradiographic binding properties and off-target profile of [18F]-Flortaucipir, [18F]-MK-6240 and [18F]-PI-2620 in human tissue specimens, and their potential binding to monoamine oxidases (MAO). Phosphor-screen and high resolution autoradiographic patterns of the three tracers were studied in the same postmortem tissue material from AD and non-AD tauopathies, cerebral amyloid angiopathy, synucleopathies, transactive response DNA-binding protein 43 (TDP-43)-frontotemporal lobe degeneration and controls. Our results show that the three tracers show nearly identical autoradiographic binding profiles. They all strongly bind to neurofibrillary tangles in AD but do not seem to bind to a significant extent to tau aggregates in non-AD tauopathies pointing to their limited utility for the in vivo detection of non-AD tau lesions. None of them binds to lesions containing β-amyloid, α-synuclein or TDP-43 but they all show strong off-target binding to neuromelanin and melanin-containing cells, as well as weaker binding to areas of hemorrhage. The autoradiographic binding signals of the three tracers are only weakly displaced by competing concentrations of selective MAO-B inhibitor deprenyl but not by MAO-A inhibitor clorgyline suggesting that MAO enzymes do not appear to be a significant binding target of any of them. These findings provide relevant insights for the correct interpretation of the in vivo behavior of these three tau PET tracers.

Definitive Radiotherapy in Patients with Clinical T1N0M0 Esophageal Squamous Cell Carcinoma: A Multicenter Retrospective Study

PURPOSE/OBJECTIVE(S)

In this study, we aimed to assess the failure pattern and survival outcomes and to analyze the optimal treatment field of definitive RT for T1N0M0 esophageal squamous cell carcinoma (ESCC).

MATERIALS/METHODS

We performed a retrospective analysis in a multi-institutional cohort of patients with histologically confirmed T1N0M0 ESCC. We included patients who underwent RT with definitive aim from 2010 to 2019. Patterns of failure were demonstrated as in-field locoregional, out-field locoregional and distant metastasis. In the survival analysis, freedom from locoregional recurrence and their association with clinicopathologic risk factors were analyzed. We performed a propensity score matching in the cT1b patients to adjust for the heterogeneity of radiation technique, radiation dose and the use of concurrent chemotherapy.

RESULTS

A total of 168 patients were included with a median follow-up of 34.0 months, and there were 20 cT1a, 94 cT1b and 24 cT1x, (cT1, not otherwise specified) patients. The rates of all and locoregional failure were 26.9% and 23.1% for cT1a and 25.0% and 22.4% for cT1b patients. 10 (10.6%) patients experienced grade ≥ 3 adverse events. Among 116 cT1b patients, 69 patients received elective nodal irradiation (ENI) and 47 patients received involved field irradiation (IFI). After propensity score matching, the 3-year FFLRR rate was 84.5% (95% Confidence Interval, 71.0 - 92.1%). There was no significant difference between the ENI and IFI patients in FFLRR (Log-rank P = 0.831). In the multivariate analysis, the use of concurrent chemotherapy was the only factor marginally associated with FFLRR (Hazard ratio, 0.17; 95% CI, 0.02 - 1.13; P = 0.067).

CONCLUSION

cT1a patients who cannot receive endoscopic resection, showed similar rates of failure compared with cT1b patients, which questioned the accuracy of the staging and raised the need for through treatment such as chemoradiotherapy. In cT1b patients, IFI using dose of 50 to 60 Gy with concurrent chemotherapy could be a reasonable treatment option.

Direct thermal injury to the popliteal artery after total knee arthroplasty

Vascular damage after total knee arthroplasty is rare. However, delayed diagnosis and management may cause adverse outcomes for patients. In particular, direct thermal injury to the popliteal artery after total knee arthroplasty is extremely rare. A 74-year-old woman presented to another institution with a left popliteal artery injury after left total knee arthroplasty. Arteriography revealed total occlusion of the popliteal artery, and emergency surgery was performed. Because of the total occlusion of the popliteal artery due to severe direct thermal injury, anastomosis was performed in an end-to-end fashion with a right great saphenous vein graft. At the time of discharge, she had no specific symptoms other than pain at the surgical site, with a palpable left dorsalis pedis pulse. While performing total knee arthroplasty, the anatomical position of the popliteal artery should be carefully considered to prevent injury.

Evaluation of the efficacy and safety of NVP-1203 and aceclofenac in patients with acute low back pain and muscle spasm: A randomized, double-blind, active-controlled, parallel, multicenter, phase 3 clinical trial

OBJECTIVE

Acute low back pain (LBP) is a common condition that can be chronic if not properly treated. Aceclofenac and eperisone hydrochloride are commonly prescribed drugs for acute LBP and muscle spasms. Therefore, NVP-1203, a fixed-dose combination of 100 mg aceclofenac and 75 mg eperisone hydrochloride, is being developed. This study aimed to evaluate the efficacy and safety of NVP-1203 compared to those of a single administration of 100 mg aceclofenac in patients with acute LBP and muscle spasms.

PATIENTS AND METHODS

Overall, 455 patients with acute LBP and muscle spasms were enrolled. The patients were assigned to NVP-1203 or Airtal group (aceclofenac 100 mg). The primary efficacy endpoint was the mean change in the 100 mm pain movement and resting visual analog scale (VAS) scores on treatment day 7.

RESULTS

The mean change in the 100 mm pain movement/resting VAS scores from baseline to day 7 was -49.7 ± 21.5/-41.0 ± 19.4 mm and -38.8 ± 18.9/-33.8 ± 18.0 mm for the NVP-1203 and Airtal groups, respectively. The differences between the two groups were statistically significant (movement, p < 0.0001; resting, p = 0.0002). Differences in least-square (LS) mean change of the 100 mm pain movement/resting VAS score between the two groups using the analysis of covariance (ANCOVA) model was -10.2/-7.4 mm, and the upper limit of the 95% confidence interval was -6.44/-4.16 mm.

CONCLUSIONS

NVP-1203 is more effective in reducing pain than the 100 mg aceclofenac alone. However, the two drugs have similar safety profiles in patients with acute LBP and muscle spasms.

Anterior resection syndrome: a randomized clinical trial of a 5-HT3 receptor antagonist (ramosetron) in male patients with rectal cancer

BACKGROUND

No effective treatment exists for anterior resection syndrome (ARS) following sphincter-saving surgery for rectal cancer. This RCT assessed the safety and efficacy of a 5-HT3 receptor antagonist, ramosetron, for ARS.

METHODS

A single-centre, randomized, controlled, open-label, parallel group trial was conducted. Male patients with ARS 1 month after rectal cancer surgery or ileostomy reversal were enrolled and randomly assigned (1 : 1) to 5 μg of ramosetron (Irribow®) daily or conservative treatment for 4 weeks. Low ARS (LARS) score was calculated after randomization and 4 weeks after treatment. The study was designed as a superiority test with a primary endpoint of the proportion of patients with major LARS between the groups. Primary outcome analysis was based on the modified intention-to-treat population. Safety was assessed by monitoring adverse events during the study.

RESULTS

: A total of 100 patients were randomized to the ramosetron (49 patients) or conservative treatment group (51 patients). Two patients were excluded, and 48 and 50 patients were analysed in the ramosetron and control groups, respectively. The proportion of major LARS after 4 weeks was 58 per cent (28 of 48 patients) in the ramosetron group versus 82 per cent (41 of 50 patients) in the control group, with a difference of 23.7 per cent (95 per cent c.i. 5.58 to 39.98, P = 0.011). There were minor adverse events in five patients, which were hard stool, frequent stool or anal pain. These were not different between the two groups. There were no serious adverse events.

CONCLUSION

: Ramosetron could be safe and feasible for male patients with ARS.

TRIAL REGISTRATION NUMBER

NCT02869984 (http://www.clinicaltrials.gov).

Association between mortality risk and the number, location, and sequence of subsequent fractures in the elderly

The mortality risk showed a positive correlation as the number of subsequent fractures increased. Hip fracture showed the greatest association with mortality risk, followed by vertebral fracture. For the combination of hip and vertebral fracture, a hip fracture after a vertebral fracture showed the highest mortality risk.

INTRODUCTION

It is unclear whether subsequent fractures or a certain location and sequence of subsequent fractures are associated with mortality risk in the elderly. We aimed to investigate the relationship between subsequent fractures and mortality risk.

METHODS

Using the Korean National Health Insurance Research Database, we analyzed the cohort data of 24,756 patients aged > 60 years who sustained fractures between 2002 and 2013. Cox regression was used to assess the mortality risk associated with the number, locations, and sequences of subsequent fractures.

RESULTS

Mortality hazard ratios (HRs) for women and men were shown to be associated with the number of subsequent fractures (one, 1.63 (95% confidence interval [CI], 1.48-1.80) and 1.42 (95% CI, 1.28-1.58); two, 1.75 (95% CI, 1.47-2.08) and 2.03 (95% CI, 1.69-2.43); three or more, 2.46(95% CI, 1.92-3.15) and 1.92 (95% CI, 1.34-2.74), respectively). For women, the mortality risk was high when hip (HR, 2.49; 95% CI, 1.80-3.44) or vertebral (HR, 1.40; 95% CI, 1.03-1.90) fracture occurred as a second fracture. Compared with a single hip fracture, there was a high mortality risk in the group with hip fracture after the first vertebral fracture (HR, 2.90; 95% CI, 1.86-4.54), followed by vertebral fracture after the first hip fracture (HR, 1.90; 95% CI, 1.12-3.22).

CONCLUSION

The mortality risk showed a positive correlation as the number of subsequent fractures increased. Hip fracture showed the greatest association with mortality risk, followed by vertebral fracture. For the combination of hip and vertebral fracture, a hip fracture after a vertebral fracture showed the highest mortality risk.

Anti-elastase and anti-hyaluronidase activity of phosvitin isolated from hen egg yolk

1. Phosvitin, a major phosphoprotein found in egg yolk, has strong antioxidant activity. Activation of elastase, collagenase, and hyaluronidase by reactive oxygen species are related to the degradation of ECM and skin aging. The objective of this study was to determine the anti-elastase and anti-hyaluronidase activity of phosvitin.2. Elastase from porcine pancreas and hyaluronidase from bovine testes were used to study the inhibitory activity of phosvitin. To elucidate the mechanism of enzyme inhibition, a Lineweaver-Burk plot was constructed.3. Phosvitin inhibited elastase and hyaluronidase activity in a dose-dependent manner. The IC₅₀ value of phosvitin was 31.6 μg/ml and 1,270 μg/ml against elastase and hyaluronidase, respectively. The analysis of elastase and hyaluronidase kinetics indicated that the apparent Michaelis constant (_appK_m) was increased by phosvitin but the V_max value was not affected.4. In conclusion, phosvitin exhibited competitive inhibitory activity against elastase and hyaluronidase. Thus, phosvitin could be used as a natural anti-aging agent in the cosmetics industry.

Cytoprotective effects of taxifolin against cadmium-induced apoptosis in human keratinocytes

Cadmium (Cd) is a heavy metal widely used in industry, and the skin is an important target of this metal. Taxifolin (Tax), a natural source of bioflavonoids found in various conifers, exerts multiple biologic effects on skin cells. However, the mechanisms by which Tax protects keratinocytes against Cd are currently unclear. We investigated the cytoprotective effects of Tax against Cd-induced apoptosis in the human HaCaT keratinocyte. The water-soluble tetrazolium salt (WST-1) assay and Annexin V/propidium iodide double-staining assay results showed that Cd-induced cell death was lower in cells treated with Tax (0–100 μM) than in cells treated with Cd alone. Additionally, a reduction of Cd-induced DNA fragmentation by Tax was shown by terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick-end labeling assay. The levels of reactive oxygen species were also lower in Cd/Tax-treated cells than in Cd-treated cells. We employed a two-dimensional electrophoresis-based proteomic analysis to identify treatment-related alterations in protein expression. Tax downregulated cathepsin B and D and upregulated hsp27, cyclophilin A, and peroxiredowin-1. Western blotting confirmed the downregulation of cathepsin B and D and the upregulation of hsp27. The cytoprotective effects of Tax against Cd-induced apoptosis were also characterized by the changes in the activity of caspase 3, -7, poly ADP-ribose polymerase, the cellular proliferation-related ERK1/2, and AKT. Furthermore, the levels of cell cycle-related proteins, such as SP1 and p21, decreased, whereas p53 level increased. We concluded that Tax reduced Cd cytotoxicity and Cd-induced apoptosis by inhibiting the apoptotic pathway.

In vitro cytotoxic and ACE-inhibitory activities of promod 278P hydrolysate of ovotransferrin from chicken egg white

Peptides released from egg proteins via enzymatic hydrolysis show various bioactivities such as antimicrobial, antioxidant, antihypertensive, and immunomodulatory properties. The objective of this study was to investigate the cytotoxic and Angiotensin Converting Enzyme (ACE)-inhibitory activities of ovotransferrin and its promod 278P enzyme hydrolysate. Ovotransferrin from egg white was hydrolyzed using promod 278P at 45°C for 3 hours. Using the MTT assay, the cytotoxicity of ovotransferrin and promod 278P hydrolysate of ovotransferrin were evaluated in human cancer cell lines of various tissue origins. The ACE-inhibitory activity was determined using the cleavage of a chromogenic substrate -Hip-His-Leu. The promod 278P hydrolysate of ovotransferrin showed a potent cytotoxicity (>90%) at 20 mg/mL in all cancer cell lines tested, but ovotransferrin did not. The IC50 value of the promod 278P hydrolysate of ovotransferrin against 5 different cancer cells were 10.05 ± 1.55, 3.45 ± 0.94, 4.43 ± 1.87, 4.92 ± 0.63, and 10.43 ± 3.91 mg/mL for MCF-7, HeLa, HepG2, HT-29, and LoVo cells, respectively. The promod 278P hydrolysate of ovotransferrin showed a strong ACE-inhibiting activity: at 10 mg/mL level, the hydrolysate showed 76.82 ± 1.28% inhibition to ACE-inhibitory activity, and 73.33 ± 2.56%, 56.85 ± 1.84%, 50.32 ± 3.71%, 17.30 ± 0.13%, and 4.52 ± 6.83% inhibitory activity at 5, 2.5, 1.25, 0.625, and 0.3125 mg/mL level, respectively. The IC50 value of the promod 278P hydrolysate of ovotransferrin was 1.53 ± 0.20 mg/mL. However, ovotransferrin did not show any inhibitory effect to angiotensin-converting enzyme activity. This result indicated that the promod 278P hydrolysate of ovotransferrin has a great potential as an anticancer and antihypertension agent for humans, but the information on the peptides responsible for the functional activities is not available yet.

Comparison between a new electronic bidet and conventional sitz baths: a manometric evaluation of the anal resting pressure in normal healthy volunteers

BACKGROUND

A bidet has been proposed as a replacement for the sitz bath. Like a sitz bath, it brings water into contact with the perineum. However, the high force of water from commercially used electronic bidets may harm the anus. We developed a new electronic bidet and evaluated its effects on anal resting pressure compared with a warm sitz bath.

METHODS

Forty volunteers used the electronic bidet and sitz bath on separate days. The electronic bidet was newly designed with warm (38 °C) water and very low force (10 mN) with a fountain type of flow. Anal resting pressure at the high-pressure zone was measured before (control) and after the electronic bidet and sitz bath. Pressure changes after bidet or sitz bath were expressed as percentages compared with control. Water temperatures and rectal temperatures were also recorded.

RESULTS

The anal resting pressures before the electronic bidet and sitz bath were 90.2 ± 24.6 and 88.1 ± 16.8 mmHg, respectively. At 3 min after the electronic bidet and sitz bath, the anal resting pressures were 71.3 ± 23.4 and 69.6 ± 19.8 mmHg, respectively. The pressure changes compared with the control were 78.2 ± 12.9 and 78.1 ± 12.5%, respectively, which were not significantly different. The maximal increase and minimal decrease were not significantly different. The rectal temperature was not elevated, and the water temperature decreased significantly with the sitz bath (p < 0.001).

CONCLUSIONS

Our new electronic bidet may reduce the anal resting pressure much like a warm sitz bath does.

Dietary supplement use and its effect on nutrient intake in Korean adult population in the Korea National Health and Nutrition Examination Survey IV (2007-2009) data

BACKGROUND/OBJECTIVES

Although there is an increasing trend of dietary supplement (DS) use, few researches have evaluated nutrient intake from DS. This study aimed to establish a nutrient database (NDB) for DS and estimate the effect of DS on total nutrient intake by Korean adults.

SUBJECTS/METHODS

The NDB for DS was established using the label information of products reported in the Korea National Health and Nutrition Examination Survey (KNHANES) IV. Of the 16,031 participants who were ≥20 years old, 2053 products were reported as being taken by 5606 subjects. But nutrient composition could be identified by searching product name only in 1158 products consumed by 3844 subjects (DS users). Total nutrient intake of DS users was obtained by combining intakes from diet and DS.

RESULTS

Dietary supplement use was higher in women, in middle-aged people and in those with higher education and low smoking and drinking preferences. Nutrients obtained from food were higher in DS users than in nonusers for most nutrients, particularly in women. When total nutrient intake was evaluated in DS users, the percentage of subjects whose intake was below the estimated average requirement for Koreans decreased for several vitamins and minerals, but the percentage of subjects whose intake was above the tolerable upper intake levels increased for vitamin A, vitamin C and iron.

CONCLUSIONS

The newly developed NDB for DS will be an important resource for more accurate assessment of nutrient intake as well as evaluation of the relationship between nutrition and health. Further research is needed to update a more comprehensive NDB applicable to diverse populations.

Establishing the Origin of Elevated Uranium Concentrations in Groundwater near the Central Ogcheon Metamorphic Belt, Korea

We examined the origin of the U-enriched groundwater in Daejeon, near the Ogcheon U zone in Korea. For this study, groundwater ionic species and C, S, and Sr isotopic compositions were analyzed. The U-enriched groundwater occurred only in the Daejeon granite region, while all the groundwater in the Ogcheon Supergroup showed very low U concentrations. In the granite region, the pedospheric or atmospheric origin of dissolved C and S means that the aquifer has been well connected to the oxidized surface environment. The Sr/Sr ratios indicated a lithospheric origin of Sr. Groundwater isotopic compositions in the Ogcheon belt varied greatly, indicating their complex sources. In this region, dissolved C originated from graphite-rich slate and limestone. The broad range of δS suggested that the composite sources included atmospheric SO for most groundwater, lithogenic SO for mine drainage and quarry water, and anthropogenic SO for polluted groundwater. This study indicates that the U-enriched groundwater is not related to the present U ores in the Ogcheon belt but is genetically associated with the granite body itself. The varying but considerable U contents within the granite body can be present as isolated groups. We infer that locally high U contents in the Daejeon granite might inherently be due to assimilation of the Ogcheon U-mineralized zone into granitic melt during the Mesozoic; however, the pH and Eh conditions except aquifer geology were very important factors in developing highly enriched U groundwater in the Daejeon granite region. Thermodynamic modeling highlights the importance of dissolved Ca and (bi-)carbonate in U geochemistry.

Volumetric response evaluation after intensity modulated radiotherapy in patients with supratentorial gliomas

Radiotherapy is frequently indicated to treat cerebral gliomas. Accurate response evaluation after radiotherapy is essential to determine the efficacy of treatment. We retrospectively analyzed the volumetric tumor response after simultaneous integrated boost-intensity modulated radiotherapy (SIB-IMRT) in patients with gliomas. Thirty-five patients (Grade II, 7 patients; Grade III, 12; and Grade IV, 16) were treated with SIB-IMRT with a median total dose of 55.9 Gy/26 fractions for Grade II and 60 Gy/25 fractions for Grade III-IV tumors. Tumor responses were evaluated for enhancing volume on post-gadolinium T1-weighted images (Vgd) and hyper-intensity volume on T2-weighted FLAIR images (V(fl)) on serial MRIs. With the median follow-up of 24.0 months, overall response rates (RRs) were 57% for V(gd) and 51% for V(fl). Tumor grade was predictive of response favoring the lower grade in Vfl with RRs of 86% for Grade II, 75% for Grade III, and 19% for Grade IV tumors (p = 0.004). Time to 50% or greater volume reduction (T50) in Vgd was 8 months for grade III. The T50 in V(fl) was approximately 24 months both for Grade II and III tumors. Majority of Grade IV tumors continued to progress and never reached the T50 in Vgd or Vfl. Responders survived longer than non-responders for V(gd) and V(fl). Volume response after radiotherapy was dependent upon tumor grade and time. LGGs are very responsive to radiotherapy with the RRs of 86% in V(fl). The response of Vfl is more protracted compared to V(gd). Further investigation is needed to determine the clinical significance of volumetric response evaluation.

Fungal peri-prosthetic joint infection after primary total knee replacement

We retrospectively reviewed 30 two-stage revision procedures in 28 patients performed for fungal peri-prosthetic joint infection (PJI) after a primary total knee replacement. Patients were followed for at least two years or until the infection recurred. The mean follow-up for patients who remained free of infection was 4.3 years (2.3 to 6.1). Overall, 17 patients were assessed as American Society of Anesthesiologists grade 3 or 4. The surgical protocol included removal of the infected implant, vigorous debridement and insertion of an articulating cement spacer. This was followed by at least six weeks of antimicrobial treatment and delayed reimplantation in all patients. The mean interval between removal of the prosthesis and reimplantation was 9.5 weeks (6 to 24). After reimplantation, patients took antifungal agents orally for a maximum of six months. Two knees became reinfected at one and two months post-operatively, respectively: one of these subsequently required arthrodesis because of uncontrolled infection. Fungal PJIs can be treated successfully by removal of all infected material, appropriate antimicrobial treatment and delayed reimplantation.

Versatility of right gastroepiploic and gastroduodenal arteries for arterial reconstruction in adult living donor liver transplantation

BACKGROUND

In cases where there is severe intimal dissection in the recipient hepatic artery (HA), or if the HA has been used already and additional operations are needed due to graft rejection or arterial occlusion, an alternative is necessary. In the present study, we have reported the feasibility of using the right gastroepiploic artery (RGEA) and gastroduodenal artery (GDA) in various situations where the HA is not a feasible option.

METHODS

Among 463 patients who underwent primary adult-to-adult living donor liver transplantation from January 2002 to July 2010, eight subjects required alternative vessels. Four recipients displayed severe intimal injury associated with previous transarterial chemoembolization (TACE); two, required a salvage operation due to hepatic artery thrombosis (HAT); and two, retransplantations due to chronic rejection. The RGEA was used in five and the GDA in three patients.

RESULTS

Postoperative Doppler ultrasonography and three-dimensional computed tomography showed patent arterial flow in all patients. However, HAT recurred in one patient who underwent a salvage operation with the RGEA; she died 2 months later. Two other patients died due to wound infection and respiratory failure within 3 months despite intact hepatic arterial flow. Four patients had no further complications during follow-up (mean = 33 months).

CONCLUSION

Although there was a discrepancy in the diameter of the HA and the RGEA (or GDA), there was no problem with mobilization and microanastomosis. We therefore believe that these vessels can be good alternatives when the hepatic artery is unavailable.

Absence of Wip1 partially rescues Atm deficiency phenotypes in mice

Wild-type p53-induced phosphatase 1 (WIP1) is a serine/threonine phosphatase that dephosphorylates proteins in the ataxia telangiectasia mutated (ATM)-initiated DNA damage response pathway. WIP1 may have a homeostatic role in ATM signaling by returning the cell to a normal pre-stress state following completion of DNA repair. To better understand the effects of WIP1 on ATM signaling, we crossed Atm-deficient mice to Wip1-deficient mice and characterized phenotypes of the double knockout progeny. We hypothesized that the absence of Wip1 might rescue Atm deficiency phenotypes. Atm null mice, like ATM-deficient humans with the inherited syndrome ataxia telangiectasia, exhibit radiation sensitivity, fertility defects, and are T-cell lymphoma prone. Most double knockout mice were largely protected from lymphoma development and had a greatly extended lifespan compared with Atm null mice. Double knockout mice had increased p53 and H2AX phosphorylation and p21 expression compared with their Atm null counterparts, indicating enhanced p53 and DNA damage responses. Additionally, double knockout splenocytes displayed reduced chromosomal instability compared with Atm null mice. Finally, doubly null mice were partially rescued from gametogenesis defects observed in Atm null mice. These results indicate that inhibition of WIP1 may represent a useful strategy for cancer treatment in general and A-T patients in particular.

A parametric study ot protease production in batch and fed-batch cultures of Bacillus firmus

Proteolytic enzymes produced by Bacillus species find a wide variety of applications in brewing, detergent, food, and leather industries. Owing to significant differences normally observed in culture conditions promoting cell growth and those promoting production of metabolites such as enzymes, for increased efficacy of bioreactor operations it is essential to identify these sets of conditions (including medium formulation). This study is focused on formulation of a semidefined medium that substantially enhances synthesis and secretion of an alkaline protease in batch cultures of Bacillus firmus NRS 783, a known superior producer of this enzyme. The series of experiments conducted to identify culture conditions that lead to improved protease production also enables investigation of the regulatory effects of important culture parameters including pH, dissolved oxygen, and concentrations of nitrogen and phosphorous sources and yeast extract in the medium on cell growth, synthesis and secretion of protease, and production of two major nonbiomass products, viz., acetic acid and ethanol. Cell growth and formation of the three nonbiomass products are hampered significantly under nitrogen, phosphorous, or oxygen limitation, with the cells being unable to grow in an oxygen-free environment. Improvement in protease production is achieved with respect to each culture parameter, leading in the process to 80% enhancement in protease activity over that attained using media reported in the literature. Results of a few fed-batch experiments with constant feed rate, conducted to examine possible enhancement in protease production and to further investigate repression of protease synthesis by excess of the principal carbon and nitrogen sources, are also discussed. The detailed investigation of stimulatory and repressory effects of simple and complex nutrients on protease production and metabolism of Bacillus firmus conducted in this study will provide useful guidelines for design of bioreactors for production of protease and bulk chemicals by this bacterium.

Availability of brain serotonin transporters in patients with restless legs syndrome

BACKGROUND

Selective serotonin reuptake inhibitors have been associated with the risk of restless legs syndrome (RLS), suggesting that dysregulation of serotonergic neurotransmission may provoke or exacerbate RLS.

METHODS

We compared the availability of serotonin transporter (SERT) between 16 drug-naïve patients with RLS and 16 healthy controls. SERT was measured in the pons and medulla via [(123)I]-2beta-carbomethoxy-3beta-(4-iodophenyl) tropane (beta-CIT) SPECT. A ratio of specific to nonspecific brain uptake (V(3)'') was used for all comparisons. RLS was diagnosed according to the criteria proposed by the National Institute of Health, and its severity was measured using the International RLS Study Group (IRLSSG) Severity Scale.

RESULTS

The availability of SERT was similar in the RLS group and the control group with regards to the pons (1.24 +/- 0.31 vs 1.24 +/- 0.25, p > 0.1) and the medulla (0.99 +/- 0.25 vs 1.00 +/- 0.23, p > 0.1). However, IRLSSG Severity Scale scores increased with decrease of SERT availability in both the pons (beta = -0.50, t = -3.19, p = 0.009) and the medulla (beta = -0.42, t = -2.44, p = 0.03).

CONCLUSIONS

Although serotonin transporter (SERT) availability in pons and medulla was similar in the restless legs syndrome (RLS) group and the control group, the severity of RLS symptoms increased as the availability of SERT decreased. These data partially support the hypothesis that an increase of serotonergic neurotransmission in the brainstem may exacerbate RLS, possibly via dual modulations on striatal dopaminergic neurotransmission and on the activities of spinal motor and sensory neurons.

Strong tunable slow and fast lights using a gain-clamped semiconductor optical amplifier

Previously demonstrated slow light is still far from applications, particularly due to the limited bandwidth and control speed. Although semiconductor-based slow light has the high bandwidth and sub-nanosecond control speed, slow light was observed only in the absorption regime with attenuation, while fast light observed in the gain regime with amplification. The large power difference in two regimes makes the use of the optical delay impractical. We report novel slow light in the gain regime, with a high power comparable to that of fast light, utilizing the anomalous gain characteristic in a gain-clamped semiconductor optical amplifier. The slow light is tunable to fast light with the current as the only variable. Additional high speed operation, fast delay control, and wide range of operation wavelength make the present approach practical.

Endoscopic ultrasound-guided versus conventional transmural drainage for pancreatic pseudocysts: a prospective randomized trial

BACKGROUND AND STUDY AIMS

Although endoscopic ultrasound (EUS)-guided transmural drainage (EUD) is preferred over conventional transmural drainage (CTD) of pancreatic pseudocysts by endoscopy in many centers, its superiority with respect to technical success and clinical outcome has not yet been demonstrated in a prospective randomized trial. We conducted this prospective randomized trial to compare the technical success and clinical outcomes of EUD and CTD in treating pancreatic pseudocysts.

PATIENTS AND METHODS

A total of 60 consecutive patients with pancreatic pseudocysts were randomly divided into two groups to undergo either EUD (n = 31) or CTD (n = 29) of pancreatic pseudocysts. The technical success rate, complications, and short-term and long-term results were prospectively evaluated.

RESULTS

The rate of technical success of the drainage was higher for EUD (94 %, 29/31) than for CTD (72 %, 21/29; P = 0.039) in intention-to-treat analysis. In cases where CTD failed (n = 8), because the pseudocysts were nonbulging, a crossover was made to EUD, which was successfully performed in all these patients. Complications occurred in 7 % of the EUD and 10 % of the CTD group ( P = 0.67). During short-term follow-up, pseudocyst resolution was achieved in 97 % (28/29) in the EUD group and in 91 % (19/21) in the CTD group ( P = 0.565). Long-term results analyzed on a per-protocol basis showed no significant difference in clinical outcomes between EUD (89 %, 33/37) and CTD (86 %, 18/21, P = 0.696).

CONCLUSIONS

We found that EUD and CTD can both be considered first-line methods of endoscopic transmural drainage of bulging pseudocysts, whereas EUD should be preferred for nonbulging pseudocysts.

Discoloration characteristics of 3 major muscles from cattle during cold storage

Discoloration characteristics of 3 major muscles (LD, Longissimus dorsi; PM, Psoas major; SM, Semimemebranosus) from Korean native cattle (Hanwoo) were monitored during 7 d of cold storage at 4 degrees C. The muscles were obtained from 12 Hanwoo carcasses at 24 h postmortem. Meat color (CIE L*, a*, b*), myoglobin (Mb) concentration, chemical form, metmyoglobin (MetMb) reducing ability (MRA), mitochondria concentration, and thiobarbituric acid reactive substance (TBARS) were measured at 1, 3, 5, and 7 d of storage. Although there were no significant differences in CIE a* and b*-values between the 3 muscles at day 1, the values of PM muscle were significantly (P < 0.05) lower than those of LD and SM muscles at day 5 and 7. PM muscle showed a rapid decrease in the oxymyoglobin (OxyMb) and an increase in MetMb, which resulted in a significantly (P < 0.05) higher percentage of MetMb in PM muscle compared to LD and SM muscles. Also, the Mb and mitochondria concentration of PM muscle was significantly (P < 0.05) higher than those of LD and SM muscles. However, there were no significant differences in MRA, pH, or TBARS between the 3 muscles during 7 d of cold storage. It was concluded that rapid discoloration (that is, MetMb accumulation) in PM muscle of Hanwoo could be due to its higher contents of Mb and mitochondria.

Is a 2-week steroid trial after initial negative investigation for malignancy useful in differentiating autoimmune pancreatitis from pancreatic cancer? A prospective outcome study

BACKGROUND

Autoimmune pancreatitis (AIP) is a peculiar type of chronic pancreatitis that responds dramatically to steroid therapy. To date, there are no worldwide consensus criteria for AIP. Different criteria with institutional preference (HISORt, revised Kim and the revised Japanese criteria) are being used to diagnose AIP, and there is controversy regarding the inclusion of steroid responsiveness in the diagnostic criteria. In contrast to the HISORt and revised Kim criteria, the revised Japanese criteria do not include steroid responsiveness as a diagnostic component.

AIMS

This study was performed to evaluate whether "a 2-week steroid trial and subsequent assessment of its response" is a useful diagnostic tool for the differentiation of AIP from pancreatic cancer. A further aim was to discover the surgical and clinical outcome for a patient who followed the treatment algorithm based on the steroid responsiveness.

PATIENTS AND METHODS

From January 2004 to June 2007, in the setting of clinically suspected AIP, 22 consecutive patients with atypical imaging for AIP, while not meeting the classic imaging criteria for pancreatic cancer, were challenged to undergo 2 weeks of steroid therapy (0.5 mg/kg of oral prednisolone per day). After the 2-week steroid trial, steroid responsiveness was assessed based on a marked improvement of narrowing of the main pancreatic duct and a reduction of the pancreatic mass. The steroid trial was continued in the case of positive steroid responsiveness, whereas surgical exploration was conducted in the case of negative steroid responsiveness. The final diagnosis was made by surgical exploration or long-term clinical and radiological follow-up.

RESULTS

All patients (n = 15) who responded to steroids were diagnosed as having AIP, whereas all patients (n = 7) who did not show a response to steroids were confirmed as having pancreatic cancer. Complete resection was possible in all (6/6; 100%), except one individual who refused surgery.

CONCLUSION

In the clinical setting of suspected AIP with the continued need for differentiation from pancreatic cancer due to atypical imaging for AIP, "a 2-week steroid trial and subsequent assessment of its response" may be helpful in confirming the diagnosis of AIP without negative consequences for resectable pancreatic cancer. However, a steroid trial should be performed carefully only by specialists in pancreatology.

Effect of chilling temperature of carcass on breast meat quality of duck

An experiment was carried out to investigate whether variations in chill water temperature affect muscle shortening and meat quality in duck breast. Three chill water temperatures were applied to duck carcasses at 20 min postmortem for 30 min, including in ice water at 0 degrees C, in cold water at 10 degrees C, and in water at 20 degrees C. Results revealed that carcass temperatures were different (P < 0.05) at 50 and 120 min of postmortem with lower temperatures at the 0 degrees C treatment (P < 0.05). The pH over the first 24 h postmortem was not different (P > 0.05) among treatments, with the exception of 50 min postmortem. The pH of breast meat in the 0 degrees C treatment was higher (P < 0.05) than that of 20 degrees C treatment at 50 min postmortem (just after chilling). No other differences (P > 0.05) in pH existed among treatments. Drip loss, cooking loss, and moisture content were not different for breast meat samples that were chilled at different temperatures. Differences (P < 0.05) were found in CIE (L, a, and b) color values. Lightness (L) increased, whereas redness (a) decreased as the chill water temperature increased. Lower yellowness (b) was found in the breast meat samples at the 10 degrees C chill water temperature. However, shear force, sarcomere length, and protein solubility were not different (P > 0.05) among the breast meat samples chilled at different chill water temperatures. It may be concluded that chilling duck carcasses at different temperature ranges from 0 to 20 degrees C did not influence muscle shortening or meat quality, except in regard to breast meat color.

Degradation of an endocrine disrupting chemical, DEHP [di-(2-ethylhexyl)-phthalate], by Fusarium oxysporum f. sp. pisi cutinase

The efficiency of two lypolytic enzymes (fungal cutinase, yeast esterase) in the degradation of di-(2-ethylhexyl)-phthalate (DEHP) was investigated. The DEHP-degradation rate of fungal cutinase was surprisingly high, i.e. almost 70% of the initial DEHP (500 mg/l) was decomposed within 2.5 h and nearly 50% of the degraded DEHP disappeared within the initial 15 min. With the yeast esterase, despite the same concentration, more than 85% of the DEHP remained even after 3 days of treatment. During the enzymatic degradation of DEHP, several DEHP-derived compounds were detected and time-course changes in composition were also monitored. During degradation with fungal cutinase, most DEHP was converted into 1,3-isobenzofurandione (IBF) by diester hydrolysis. In the degradation by yeast esterase, two organic chemicals were produced from DEHP: IBF and an unidentified compound (X). The final chemical composition after 3 days was significantly dependent on the enzyme used. Fungal cutinase produced IBF as a major degradation compound. However, in the DEHP degradation by yeast esterase, compound X was produced in abundance in addition to IBF. The toxic effects of the final degradation products were investigated, using various recombinant bioluminescent bacteria and, as a result, the degradation products from yeast esterase were shown to contain a toxic hazard, causing oxidative stress and damage to protein synthesis.

Unique properties of four lactobacilli in amino acid production and symbiotic mixed culture for lactic acid biosynthesis

With four Lactobacilli--L. delbrueckii subsp. lactis (ATCC 12315), L. casei (NRRL-B1445), L. delbrueckii (NRRL-B445), and L. heveticus (NRRL-B1937)--the characteristics of cell growth and production of lactate and amino acids were investigated. Especially, the time-course variation in concentration of amino acids (classified into alanine, serine, aspartate, glutamate, aromatic amino acid, and histidine families) was estimated in detail, and the results were systematically compared. It was elucidated that L. delbrueckii (NRRL-B445) and L. helveticus (NRRL-B1937) had quite different characteristics in growth, lactic acid synthesis, and amino acid production. L. helveticus (NRRL-B1937) was superior in the production of amino acids as well as in cell growth, but showed very poor ability in lactic acid production. However, L. delbrueckii (NRRL-B445) showed higher yield of lactic acid despite repressed cell growth, but suffered from severe amino acid deficiency in culture. By modulating the initial concentration of each strain in the mixed culture containing both L. delbrueckii (NRRL-B445) and L. helveticus (NRRL-B1937), the lactic acid production (i.e., the amount of lactic acid produced and lactic acid yield to glucose consumed) was significantly improved, presumably via symbiotic interaction between the two strains.

Removal of chromium from water and wastewater by ion exchange resins

Removal of chromium from water and wastewater is obligatory in order to avoid water pollution. Batch shaking adsorption experiments were carried out to evaluate the performance of IRN77 and SKN1 cation exchange resins in the removal of chromium from aqueous solutions. The percentage removal of chromium was examined by varying experimental conditions viz., dosage of adsorbent, pH of the solution and contact time. It was found that more than 95% removal was achieved under optimal conditions. The adsorption capacity (k) for chromium calculated from the Freundlich adsorption isotherm was found to be 35.38 and 46.34 mg/g for IRN77 and SKN1 resins, respectively. The adsorption of chromium on these cation exchange resins follows the first-order reversible kinetics. The ion exchange resins investigated in this study showed reversible uptake of chromium and, thus, have good application potential for the removal/recovery of chromium from aqueous solutions.

Cleaning strategies for flux recovery of an ultrafiltration membrane fouled by natural organic matter

One of the most common problems encountered in water treatment applications of membranes is fouling. Natural organic matter (NOM) represents a particularly problematic foulant. Membranes may be fouled by relatively hydrophilic and/or hydrophobic NOM components, depending on NOM characteristics, membrane properties, and operating conditions. To maximize flux recovery for an NOM-fouled ultrafiltration membrane (NTR 7410), chemical cleaning and hydraulic rinsing with a relatively high cross-flow velocity were investigated as cleaning strategies. The modification of the membrane surface with either an anionic or a cationic surfactant was also evaluated to minimize membrane fouling and to enhance NOM rejection. Foulants from a hydrophobic NOM source (Orange County ground water (OC-GW)) were cleaned more effectively in terms of permeate flux by acid and caustic cleanings than foulants from a relatively hydrophilic NOM source (Horsetooth surface water (HT-SW)). An anionic surfactant (sodium dodecyl sulfate (SDS)) was not effective as a cleaning agent for foulants from either hydrophobic or hydrophilic NOM sources. High ionic strength cleaning with 0.1 M NaCl was comparatively effective in providing flux recovery for NOM-fouled membranes compared to other chemical cleaning agents. Increased cross-flow velocity and longer cleaning time influenced the efficiency of caustic cleaning, but not high ionic strength cleaning. The membrane was successfully modified only with the cationic surfactant; however, enhanced NOM rejection was accompanied by a significant flux reduction.

A study on hexachromic ion selective electrode based on supported liquid membranes

An ion selective electrode (ISE) for determining Cr(VI) using supported liquid membranes (SLMs) containing trioctylphosphine oxide (TOPO) was investigated in this study. TOPO, as a carrier, had a high selectivity for Cr(VI) against interfering ions such as sulfate, nitrate, nitrite, and chloride. The composition of the SLM was optimized as 0.193 g TOPO/1 mL NPOE (o-nitrophenyl octyl ether)/0.5 g poly (vinyl chloride) for detection of Cr(VI). The Cr(VI) concentration was measured in the range of 1 x 10(-3) to 1 x 10(-6) M with the SLM prepared in the study. It seemed that Cr(VI) was transported in the SLM as a triply charged ion indicated by the slope of the emf response. Selectivity coefficients and detection limits of Cr(VI) in the presence of interfering ions were determined experimentally using the fixed interference method.

Comparison between posterolateral fusion with pedicle screw fixation and anterior interbody fusion with pedicle screw fixation in adult spondylolytic spondylolisthesis

There have been many reports regarding various operative methods for spondylolytic spondylolisthesis. However, there have been no reports regarding the comparison between posterolateral fusion (PLF) with pedicle screw fixation (PSF) and anterior lumbar interbody fusion (ALIF) with PSF. The purpose of the current study was to compare the clinical outcomes of PLF with PSF and ALIF with PSF, and to help in the selection of treatment options. Fifty-six patients with spondylolytic spondylolisthesis who underwent PLF with PSF (group 1, 35 patients) or who underwent ALIF with PSF (group 2, 21 patients) were studied. Minimum follow-up was 2 years. Demographic variables and disease state were similar for the two groups. We studied operating time, amount of blood loss, duration of hospital stay, clinical outcomes, complications, time at which fusion was complete, fusion rate, and radiological measurements. There were no significant differences between the two groups in terms of the amount of blood loss, duration of hospital stay, back pain, radiating pain, fusion rate, or complication rate. However, in group 2, the operation time and the time at which fusion became complete was longer, and in group 1 there was significant radiological reduction loss. In conclusion, PLF with PSF was just as effective as ALIF with PSF in terms of clinical outcomes, but ALIF with PSF was superior to PLF with PSF in terms of the prevention of reduction loss. Anterior support would be helpful for preventing reduction loss in cases of spondylolytic spondylolisthesis of the lumbar spine.

Pathological findings in cumulative irritation induced by SLS and croton oil in hairless mice

It is known that the pathological features of acute irritant contact dermatitis are specific according to the irritant. However, in chronic irritant contact dermatitis, it is not clear whether specific patterns exist. To investigate whether the specific pathology of acute irritant contact dermatitis is sustained in chronic irritant contact dermatitis, sodium lauryl sulfate (SLS) and croton oil were applied 3x a week for 2 weeks on the dorsal skin of hairless mice using Finn Chambers. The pathologic changes induced by irritants at various concentrations were evaluated using H&E and Luna's staining, as well as immunohistochemistry for 5-bromo-2-deoxyuridine (BrdU), keratin 6 and loricrin. Our results showed that epidermal hyperplasia and inflammatory infiltration were relatively marked in the groups treated with higher concentrations of irritants. These features were more prominent in the 1% croton oil treated group than in the 0.25% SLS treated group. However, lower concentrations of irritants resulted in very similar histological changes, characterized by epidermal hyperplasia with minimal inflammatory infiltration, irrespective of the chemical. Our results suggest that the histological responses to irritants vary with concentration in cumulative irritation, as in acute irritation, but repetitive mild irritation may evoke common histological changes, characterized by epidermal hyperplasia with minimal inflammatory infiltration, irrespective of the chemical used.

Recurrent lumbar disc herniation: results of operative management

STUDY DESIGN

A retrospective evaluation of 28 patients with recurrent lumbar disc herniation.

OBJECTIVES

To analyze the outcome of the revisions (repeat discectomy), the risk factors of recurrent disc herniation, and the factors that influenced the outcomes of repeat discectomy.

SUMMARY OF BACKGROUND DATA

Recurrent herniation following disc excision has been reported in 5-11% of patients. There have been many studies on recurrent disc herniation, but these studies have analyzed mixed patient populations.

METHODS

Recurrent lumbar disc herniation was defined as disc herniation at the same level, regardless of ipsilateral or contralateral herniation, with a pain-free interval greater than 6 months. Eight women and 20 men were studied. The levels of disc herniation were L4-L5 (19 cases) and L5-S1 (9 cases). Gadolinium-enhanced magnetic resonance imaging was performed in all patients. Revision surgery was performed in all patients by using conventional open discectomy. The pain-free interval, side and degree of herniation, operation time, duration of hospital stay, and clinical improvement rate were recorded.

RESULTS

The mean pain-free interval was 60.8 months. There were 21 cases of ipsilateral herniation and 7 cases of contralateral herniation. The degrees of herniation in revision were protrusion (14 cases), subligamentous extrusion (3 cases), transligamentous extrusion (8 cases), and sequestration (3 cases). The degrees of herniation in the previous discectomy were protrusion (17 cases), subligamentous extrusion (10 cases), and transligamentous extrusion (1 case). The length of surgery was significantly different (P = 0.003) between the revision surgery and the previous discectomy. There were no significant differences between revision and previous surgery in terms of hospital stay or clinical improvement rates. Age, gender, smoking, professions, traumatic events, level and degree of herniation, and pain-free interval did not affect the clinical outcomes.

CONCLUSION

Conventional open discectomy as a revision surgery for recurrent lumbar disc herniation showed satisfactory results that were comparable with those of primary discectomy. Based on the results of this study, repeat discectomy can be recommended for the management of recurrent lumbar disc herniation.

Lumbosacral scoliotic list by lumbar disc herniation

STUDY DESIGN

A prospective study of 45 patients with lumbar disc herniation and scoliotic list who had undergone conventional open discectomy.

OBJECTIVES

To determine the association between the location of the disc herniation and the direction of sciatic scoliotic list and to clarify the mechanism of sciatic scoliosis.

SUMMARY OF BACKGROUND DATA

The association between the scoliotic list and lumbar disc herniation is well known. However, there have been few studies regarding the direction of scoliotic list and the location of the disc herniation observed during surgery.

METHODS

The direction of scoliotic list, the preoperative and postoperative Cobb's angle, and the displacement of the first lumbar vertebra from the center sacral line were measured. The location, side, and degree of disc herniation were observed during surgery.

RESULTS

There was no statistically significant association observed between the location or degree of nerve root compression and the direction or degree of sciatic scoliosis. Moreover, there was no statistically significant association observed between the location or degree of nerve root compression and the displacement of the first lumbar spine from the center sacral line. However, there was a significant association between the side of the disc herniation and the direction of sciatic scoliosis. Most of the sciatic scoliotic list disappeared after surgical decompression.

CONCLUSION

The direction of sciatic scoliosis was not observed to be associated with the location of nerve root compression, although it was related to the side of disc herniation.

Naturally acquired antibody responses to the C-terminal region of merozoite surface protein 1 of Plasmodium vivax in Korea

We expressed a protein in Saccharomyces cerevisiae in order to evaluate the humoral immune responses to the C-terminal region of the merozoite surface protein 1 of Plasmodium vivax. This protein (Pv200(18)) had a molecular mass of 18 kDa and was reactive with the sera of individuals with patent vivax malaria on immunoblotting analysis. The levels of immunoglobulin M (IgM) and IgG antibodies against Pv200(18) were measured in 421 patients with vivax malaria (patient group), 528 healthy individuals from areas of nonendemicity (control group 1), and 470 healthy individuals from areas of endemicity (control group 2), using the indirect enzyme-linked immunosorbent assay (ELISA) method. To study the longevity of the antibodies, 20 subjects from the patient group were also tested for the antibody levels once a month for 1 year. When the cutoff values for seropositivity were determined as the mean + 3 x standard deviation of the antibody levels in control group 1, both IgG and IgM antibody levels were negative in 98.5% (465 of 472) of control group 2. The IgG and IgM antibodies were positive in 88.1% (371 of 421) and 94.5% (398 of 421) of the patient group, respectively. The IgM antibody became negative 2 to 4 months after the onset of symptoms, whereas the IgG antibody usually remained positive for more than 5 months. In conclusion, indirect ELISA using Pv200(18) expressed in S. cerevisiae may be a useful diagnostic method for vivax malaria.

Human intervertebral disc cells are genetically modifiable by adenovirus-mediated gene transfer: implications for the clinical management of intervertebral disc disorders

STUDY DESIGN

Human intervertebral disc cells were cultured in monolayer and treated with adenovirus-containing marker genes to determine the susceptibility of the cells to adenovirus-mediated gene transfer.

OBJECTIVES

To test the efficacy of the adenovirus-mediated gene transfer technique for transferring exogenous genes to human intervertebral disc cells in vitro.

SUMMARY OF BACKGROUND DATA

Upregulated proteoglycan synthesis after direct in vivo adenovirus-mediated transfer of growth factor genes to the rabbit intervertebral disc has previously been reported. Before contemplating extending this approach to the treatment of human disc disease, it is necessary to demonstrate that human intervertebral disc cells are indeed susceptible to adenovirus-mediated gene transduction.

METHODS

Human intervertebral disc cells were isolated from disc tissue obtained from 15 patients during surgical disc procedures. The cells were cultured in monolayer and treated with saline containing five different doses of adenovirus carrying the lacZ gene (Ad/CMV-lacZ), saline containing adenovirus carrying the luciferase gene (Ad/CMV-luciferase), or saline alone. Transgene expression was analyzed by 5-bromo-4-chloro-3-indolyl-beta-galactosidase (X-Gal) staining and luciferase assay.

RESULTS

Adenovirus efficiently transferred lacZ and luciferase marker genes to cells from degenerated discs as well as to cells from nondegenerated discs. A minimum dose of 150 MOI Ad/CMV-lacZ was found to be sufficient to achieve transduction of approximately 100% of disc cells-regardless of patient age, sex, surgical indication, disc level, and degeneration grade. No statistically significant difference in the luciferase activities could be detected in disc cell cultures from degenerated and nondegenerated discs treated with Ad/CMV-luciferase.

CONCLUSIONS

In vitro transducibility of human intervertebral disc cells by adenovirus is relatively insensitive to disc degeneration grade. Because the rate-limiting step for successful gene therapy is the ability to transfer genes efficiently to the target tissue, the achievement of efficient gene transfer to human intervertebral disc cells(using a direct, adenovirus-mediated approach) is an important and necessary step in the development of gene therapy strategies for the management of human intervertebral disc disorders.

Effect of cataract extraction and posterior chamber lens implantation on outflow facility and its response to pilocarpine in Korean subjects

AIM

To investigate the effect of the lens on outflow facility in Korean patients with cataracts.

METHODS

Intraocular pressure was measured by Goldmann applanation tonometry in 42 patients with cataracts and outflow facility was determined by tonography preoperatively, before and after instillation of pilocarpine. All patients received clear corneal phacoemulsification and silicone foldable intraocular lens implantation within the capsular bag by one surgeon. Two months after surgery, slit lamp examination and gonioscopy were performed and intraocular pressure and outflow facility were again determined. Statistical analysis was carried out using the Student's paired t test.

RESULTS

There were no anterior chamber reactions and no visible trabecular meshwork damage 2 months after surgery. Intraocular pressure 2 months after lens extraction decreased by a mean of 2.4 (SE 0.4) mm Hg (p<0.001) compared with the preoperative value; postoperative outflow facility with and without pilocarpine increased by 0.080 (0.019) microl/min/mm Hg (p<0.001) and 0.045 (0.014) microl/min/mm Hg (p<0.001), respectively, at 2 months compared with preoperative values. The facility response to pilocarpine after lens extraction, relative to the baseline value and preoperative response, increased by 10.7 (7.1)% which was not statistically significant (p>0.1).

CONCLUSION

Lens extraction causes a reduction in intraocular pressure and an increase in outflow facility in Korean subjects. Pilocarpine causes an increase in outflow facility which persists after cataract extraction and posterior chamber lens implantation.

MR arthrography of the labral capsular ligamentous complex in the shoulder: imaging variations and pitfalls

OBJECTIVE

Using MR arthrography, we examined normal anatomy, anatomic variations, and pitfalls of imaging the labral capsular ligamentous complex in the asymptomatic shoulder.

SUBJECTS AND METHODS

We obtained 108 MR arthrograms of the glenohumeral joint in 95 asymptomatic volunteers with axial (108 shoulders) and oblique coronal (56 shoulders) images. We examined labral shape, patterns of capsular insertion, presence or absence of glenohumeral ligaments, and pitfalls of imaging. Our patients were men (auxiliary policemen) between 19 and 24 years old (mean age, 21 years).

RESULTS

The shapes of labra were triangular (anterior part, 64%; posterior part, 47%), round (17%; 33%), flat (2%; 17%), cleaved (11%; 1%), notched (3%; 0%), or absent (2%; 2%). Using the system of Mosely and Overgaard, the anterior capsular insertion was type 1 in 63% of shoulders, type 2 in 20%, and type 3 in 17%; the posterior capsular insertion was type 1 in 60% of shoulders, type 2 in 31%, and type 3 in 9%. The superior and inferior glenohumeral ligaments were present in 99% of shoulders, but the middle glenohumeral ligament was present in only 79%. We also detected many pitfalls of MR imaging in identifying findings such as the undercutting of the labrum by cartilage (32% of shoulders), prominent axillary folds (46%), sublabral holes (7%) or recesses (33%), Buford complexes (2%), and sulci between the biceps tendon and superior labrum (30%).

CONCLUSION

Knowledge of normal anatomy and anatomic variations of the labral complex is important for the examination of the shoulder with MR arthrography.

Deep vein thrombosis after major spinal surgery: incidence in an East Asian population

STUDY DESIGN

A prospective study of 313 patients who underwent major spinal surgery.

OBJECTIVES

To determine the incidence of deep vein thrombosis after major spinal surgery in an east Asian population without antithrombotic prophylaxis.

SUMMARY OF BACKGROUND DATA

Spinal surgery has been associated with few thrombotic complications (2-14%) compared with other reconstructive surgeries (20-70%). It has also been well documented that the incidence of deep vein thrombosis in east Asians (10%) is lower than in westerners (20-70%) in total joint replacements. There has been no previous report on the incidence of deep vein thrombosis after reconstructive spinal surgery in east Asians.

METHODS

Three hundred thirteen patients who underwent major spinal surgery were evaluated prospectively. All patients were examined with duplex ultrasonography assessments of both lower extremities. No specific antithrombotic prophylaxis were used in any patients before or after surgery.

RESULTS

There were four patients with positive findings of deep vein thrombosis on duplex ultrasonography, and there was only one with clinically symptomatic deep vein thrombosis. The overall incidence of thrombotic complications was 1.3%, and the incidence of symptomatic deep vein thrombosis was 0.3%.

CONCLUSION

Considering the low rate of deep vein thrombosis, routine screening and prophylaxis for deep vein thrombosis appears unwarranted in east Asians before or after major spinal surgery.

Radiographic knee dimensions in discoid lateral meniscus: comparison with normal control

We reviewed the knee radiographs of 68 cases of arthroscopically proven discoid lateral meniscus, including 42 cases of complete type and 26 cases of incomplete type discoid lateral meniscus. Knee radiographs of 70 cases that had no arthroscopic evidence of pathology of the meniscus were used as controls. We excluded patients who had significant trauma history and who were under 16 years of age or over 60 years to avoid measuring radiographs of skeletally immature or degenerative knees. The absolute values and relative normalized values of specific knee dimensions, such as a squared-off appearance of the lateral femoral condyle, widened femorotibial joint space, cupping of the lateral tibial plateau, obliquity of the lateral tibial plateau articular surface, high fibular head, and hypoplasia of the lateral intercondylar spine, were compared between the patients with discoid lateral meniscus and the normal controls. Among those dimensions, high fibular head and widened lateral tibiofemoral joint space showed statistically significant differences between the discoid lateral meniscus group and normal control group. We suggest that these findings would be useful in screening lateral discoid meniscus on plain radiography.

Tumor volume change as a predictor of chemotherapeutic response in osteosarcoma

The change in osteosarcoma tumor volume after preoperative adjuvant chemotherapy and its relationship to the histopathologic response was investigated using various reproducible volumetric methods. Tumor volume was measured before and after chemotherapy in 41 patients with osteosarcoma using an ellipsoid formula in plain radiography and magnetic resonance imaging and three-dimensional magnetic resonance imaging measurement. Based on intraobserver and interobserver variability for the volumetric measurements of each method, three-dimensional magnetic resonance imaging measurement was the most reproducible. In three-dimensional magnetic resonance measurements, the correlation of the histopathologic response with absolute and relative total tumor volume changes and extraosseous volume change were significant. The good responder group showed a greater reduction in tumor volume after chemotherapy, although there was no significant difference in pretreatment tumor volume between the good and poor responder groups. The group with a decreased or stable tumor volume represented a good histopathologic response with a sensitivity of 85%, specificity of 76%, and positive predictive value of 88%. The change in tumor volume of osteosarcoma measured by three-dimensional magnetic resonance imaging could predict histopathologic response after three cycles of neoadjuvant chemotherapy.

A kinetic study on oxidation of pentachlorophenol by ozone

The kinetics of pentachlorophenol (PCP) ozonation in terms of the gaseous O3 and dissolved PCP concentrations has been investigated. When the O3 concentration in the gas phase was in the range of 10 to 40 g O3/m3, the O3 dissolved for a short time period was proportional to the gaseous O3 concentration. In this range, the ozonation reaction was first order for each reactant and the overall reaction was second order. At 25 degrees C, in an aqueous solution, the reaction rate constant was estimated to be 10.048 L/mol.sec. The reaction rate was much greater than the mass-transfer rate, indicating that the reaction of O3 and PCP was an interface reaction on the surface of gaseous O3 bubbles. The final product of the PCP ozonation was oxalic acid, with the carbon yield of the reaction being 59.4%. The ozonation of PCP in the aqueous solution was not a radical reaction but a direct reaction between O3 and PCP molecules under the conditions investigated in this study, since O3 has a high selectivity toward PCP. The reaction rate increased with the reaction temperature up to 35 degrees C but decreased at temperatures greater than 35 degrees C due to the decreased solubility of O3. The addition of H2O2 did not increase the reaction rate significantly.

Detection of radiation effects using recombinant bioluminescent Escherichia coli strains

Effects of ionizing radiation (0.1-500 Gy) on recombinant Escherichia coli cells containing the stress promoters recA, grpE, or katG, fused to luxCDABE, were characterized by monitoring transcriptional responses reflected by the bioluminescent output. The minimum dose of gamma-irradiation detected by E. coli DPD2794 (recA::luxCDABE) was about 1.5 Gy, while the maximum response was obtained at 200 Gy. The amount of emitted bioluminescence increased proportionally with the gamma-ray doses which were found to elicit a DNA damage response in a range of 1-50 Gy. In addition, the cell growth rate was severely, but transiently, retarded by about 50 Gy. Quantification of the gamma-ray dose may be possible using the recA promoter fusion, since linear enhancement of the bioluminescence emission with increasing gamma-ray dose was observed. Other irradiated strains (50 Gy) responsive to either oxidative stress (DPD2511, katG::luxCDABE) or protein-damaging stress (TV1061, grpE::luxCDABE) did not display an increased bioluminescent output, while DPD2794 irradiated by the same dose of gamma-rays gave a significant bioluminescent output. This indicates that the recA promoter is the one most suitable for developing a biosensor for ionizing radiation.

Endoscopic bone graft for delayed union and nonunion

We performed endoscopic bone grafting for eight patients of delayed union and nonunion which developed after femoral and humeral shaft fractures. The mean interval from initial intervention to endoscopic bone grafting was 7.3 months. Six patients of delayed union and nonunion healed at 4.1 months on average. Two patients had unsatisfactory healing and eventually underwent non-endoscopic revisional surgery. There was no intraoperative on postoperative complication. Endoscopic bone grafting can be a less invasive alternative, obtaining rapid bone union in cases of compromised healing of the diaphyseal fracture.