Toxicological Evaluation of a Probiotic-Based Delivery System for P8 Protein as an Anti-Colorectal Cancer Drug

Purpose

This study aimed to toxicological evaluate a probiotics-based delivery system for p8 protein as an anti-colorectal cancer drug.

Introduction

Lactic acid bacteria (LAB) have been widely ingested for many years and are regarded as very safe. Recently, a Pediococcus pentosaceus SL4 (PP) strain that secretes the probiotic-derived anti-cancer protein P8 (PP-P8) has been developed as an anti-colorectal cancer (CRC) biologic by Cell Biotech. We initially identified a Lactobacillus rhamnosus (LR)-derived anti-cancer protein, P8, that suppresses CRC growth. We also showed that P8 penetrates specifically into CRC cells (DLD-1 cells) through endocytosis. We then confirmed the efficacy of PP-P8, showing that oral administration of this agent significantly decreased tumor mass (~42%) relative to controls in a mouse CRC xenograft model. In terms of molecular mechanism, PP-P8 induces cell-cycle arrest in G₂ phase through down-regulation of Cyclin B1 and Cdk1. In this study, we performed in vivo toxicology profiling to obtain evidence that PP-P8 is safe, with the goal of receiving approval for an investigational new drug application (IND).

Methods

Based on gene therapy guidelines of the Ministry of Food and Drug Safety (MFDS) of Korea, the potential undesirable effects of PP-P8 had to be investigated in intact small rodent or marmoset models prior to first-in-human (FIH) administration. The estimated doses of PP-P8 for FIH are 1.0×10¹⁰ – 1.0×10¹¹ CFU/person (60 kg). Therefore, to perform toxicological investigations in non-clinical animal models, we orally administered PP-P8 at doses of 3.375 × 10¹¹, 6.75 × 10¹¹, and 13.5×10¹¹ CFU/kg/day; thus the maximum dose was 800–8000-fold higher than the estimated dose for FIH.

Results

In our animal models, we observed no adverse effects of PP-P8 on clinicopathologic findings, relative organ weight, or tissue pathology. In addition, we observed no inflammation or ulceration during pathological necropsy.

Conclusion

These non-clinical toxicology studies could be used to furnish valuable data for the safety certification of PP-P8.

A synthetic probiotic engineered for colorectal cancer therapy modulates gut microbiota

BACKGROUND

Successful chemoprevention or chemotherapy is achieved through targeted delivery of prophylactic agents during initial phases of carcinogenesis or therapeutic agents to malignant tumors. Bacteria can be used as anticancer agents, but efforts to utilize attenuated pathogenic bacteria suffer from the risk of toxicity or infection. Lactic acid bacteria are safe to eat and often confer health benefits, making them ideal candidates for live vehicles engineered to deliver anticancer drugs.

RESULTS

In this study, we developed an effective bacterial drug delivery system for colorectal cancer (CRC) therapy using the lactic acid bacterium Pediococcus pentosaceus. It is equipped with dual gene cassettes driven by a strong inducible promoter that encode the therapeutic protein P8 fused to a secretion signal peptide and a complementation system. In an inducible CRC cell-derived xenograft mouse model, our synthetic probiotic significantly reduced tumor volume and inhibited tumor growth relative to the control. Mice with colitis-associated CRC induced by azoxymethane and dextran sodium sulfate exhibited polyp regression and recovered taxonomic diversity when the engineered bacterium was orally administered. Further, the synthetic probiotic modulated gut microbiota and alleviated the chemically induced dysbiosis. Correlation analysis demonstrated that specific bacterial taxa potentially associated with eubiosis or dysbiosis, such as Akkermansia or Turicibacter, have positive or negative relationships with other microbial members.

CONCLUSIONS

Taken together, our work illustrates that an effective and stable synthetic probiotic composed of P. pentosaceus and the P8 therapeutic protein can reduce CRC and contribute to rebiosis, and the validity and feasibility of cell-based designer biopharmaceuticals for both treating CRC and ameliorating impaired microbiota. Video abstract.

Probiotic-derived p8 protein induce apoptosis via regulation of RNF152 in colorectal cancer cells

Worldwide, colorectal cancer (CRC) is one of the most common cancers and is a leading cause of cancer-related deaths. Accumulating evidence suggests that probiotics suppress the development of various cancers including CRC. Recently, we reported a Lactobacillus rhamnosus (LR)-derived 8 kDa protein (p8) that displayed anti-cancer properties in CRC cells. However, the precise anti-cancer mechanism of p8 and its target genes has not been fully examined. In the present study, we reveal that p8 leads to apoptotic cells and cleaved PARP1 expression in a mouse xenograft model of CRC. Additionally, we identified Ring finger protein 152 (RNF152) as a putative target of p8 using RNA-sequencing. Furthermore, the expression levels of RNF152 were increased following in vivo and in vitro treatment with p8. We also found that p8 leads to the accumulation of cleaved PARP1 in CRC cells. These results suggest that p8 induces apoptosis via regulation of RNF152, thus inhibiting the development of CRC.

Colorectal Cancer Therapy Using a Pediococcus pentosaceus SL4 Drug Delivery System Secreting Lactic Acid Bacteria-Derived Protein p8

Despite decades of research into colorectal cancer (CRC), there is an ongoing need for treatments that are more effective and safer than those currently available. Lactic acid bacteria (LAB) show beneficial effects in the context of several diseases, including CRC, and are generally regarded as safe. Here, we isolated a Lactobacillus rhamnosus (LR)-derived therapeutic protein, p8, which suppressed CRC proliferation. We found that p8 translocated specifically to the cytosol of DLD-1 cells. Moreover, p8 down-regulated expression of Cyclin B1 and Cdk1, both of which are required for cell cycle progression. We confirmed that p8 exerted strong anti-proliferative activity in a mouse CRC xenograft model. Intraperitoneal injection of recombinant p8 (r-p8) led to a significant reduction (up to 59%) in tumor mass when compared with controls. In recent years, bacterial drug delivery systems (DDSs) have proven to be effective therapeutic agents for acute colitis. Therefore, we aimed to use such systems, particularly LAB, to generate the valuable therapeutic proteins to treat CRC. To this end, we developed a gene expression cassette capable of inducing secretion of large amounts of p8 protein from Pediococcus pentosaceus SL4 (PP). We then confirmed that this protein (PP-p8) exerted anti-proliferative activity in a mouse CRC xenograft model. Oral administration of PP-p8 DDS led to a marked reduction in tumor mass (up to 64%) compared with controls. The PP-p8 DDS using LAB described herein has advantages over other therapeutics; these advantages include improved safety (the protein is a probiotic), cost-free purification, and specific targeting of CRC cells.

Effect of maternally derived antibody on sequential infection with highly virulent bursal disease virus in newly hatched broilers

Maternally derived antibodies (MDAs) are important for protection against very virulent infectious bursal disease virus (vvIBDV). In this study, 5-day-old commercial broilers with non-uniform MDA titers (with a coefficient of variation of 50%) were challenged with vvIBDV and given free contact with each other during a 2-week period. The chicks were assigned to four MDA-titer subgroups, GI-1 (very low MDA), GI-2 (low MDA), GI-3 (medium MDA), and GI-4 (high MDA). Transient symptoms of infection were observed in 35.7% of challenged birds. Body weight gain was significantly lower in GI-2, GI-3, and GI-4 birds than in an unchallenged control group. Seroconversion was observed in GI-1 birds and some GI-2 birds. The frequency of virus shedding via the cloaca in vvIBDV-challenged birds increased from 7.1% of GI birds at 5 days post inoculation (dpi) to 35.7% at 14 dpi. The timing of virus shedding was progressively later from GI-1 to GI-4. At 14 dpi, significant atrophy of the bursa of Fabricius (BF) was observed in GI birds compared with GII controls; atrophy was most severe in GI-1 birds and least severe in GI-4 birds. BF lesion scores decreased from GI-1 to GI-4. The proportion of birds with IBDV antigen in the BF at 14 dpi was higher in GI-2 and GI-3 than in GI-1 and GI-4, whereas the viral load in positive birds increased from GI-1 to GI-4. Our results indicate that high levels of MDAs would protect chicks from initial vvIBDV infection but that progressive decay of these MDAs would result in delayed infection by virus shedding in initially infected birds with low MDA titers, resulting in continuous circulation of the virus in a flock with non-uniform MDA titers.

Nanomatrix Coated Stent Enhances Endothelialization but Reduces Platelet, Smooth Muscle Cell, and Monocyte Adhesion under Physiologic Conditions

Cardiovascular disease is presently the number one cause of death worldwide. Current stents used to treat cardiovascular disease have a litany of unacceptable shortcomings: adverse clinical events including restenosis, neointimal hyperplasia, thrombosis, inflammation, and poor re-endothelialization. We have developed a biocompatible, multifunctional, peptide amphiphile-based nanomatrix coating for stents. In this study, we evaluated the ability of the nanomatrix coated stent to simultaneously address the issues facing current stents under physiological flow conditions in vitro. We found that the nanomatrix coated stent could increase endothelial cell migration, adhesion, and proliferation (potential for re-endothelialization), discourage smooth muscle cell migration and adhesion (potential to reduce neointimal hyperplasia and restenosis), and decrease both platelet activation and adhesion (potential to prevent thrombosis) as well as monocyte adhesion (potential to attenuate inflammatory responses) under physiological flow conditions in vitro. These promising results demonstrate the potential clinical utility of this nanomatrix stent coating, and highlight the importance of biocompatibility, multifunctionality, and bioactivity in cardiovascular device design.

A probiotic combination attenuates experimental colitis through inhibition of innate cytokine production

Inflammatory bowel disease (IBD) is a severe immune cell-mediated syndrome characterised by extensive inflammatory and effector mucosal responses leading to tissue destruction in the colon and small intestine. The leading hypothesis is that dysbiosis of the gut flora causes an excessive immune response and inflammation in the gastrointestinal track. Lactic acid bacteria (LAB) can correct dysbiosis of the normal microbiota. In the current study, the therapeutic potential of seven LAB strains in combination to treat IBD was evaluated using experimental colitis model. This LAB cocktail, designated GI7, includes four strains of Lactobacillus acidophilus, Lactobacillus plantarum, Lactobacillus rhamnosus, Lactococcus lactis, two strains of Bifidobacterium bifidum, Bifidobacterium breve, and one strain of Streptococcus thermophilus. We confirmed that GI7 suppressed pro-inflammatory cytokines in Raw264.7 macrophages. When dextran sulphate sodium-induced colitic mice were treated with GI7, their symptoms of colitis, as assessed by body weight, colon length, myeloperoxidase activity, intestinal bleeding, and histological damage, were reduced compared to untreated mice. In addition, GI7 treatment significantly inhibited the production of innate pro-inflammatory cytokines during colitic progression. Therefore, we suggest that GI7, a combination of seven LAB, has a potential role in the treatment of IBD.

A Probiotic Preparation Alleviates Atopic Dermatitis-Like Skin Lesions in Murine Models

Atopic dermatitis (AD) is a chronic inflammatory skin disease with a complex etiology that encompasses immunologic responses. AD is frequently associated with elevated immunoglobulin (Ig) E levels, and common environmental factors contribute to its pathogenesis. Several recent studies have documented the role of specific lactic acid bacteria in the treatment and prevention of AD in humans and mice. In this study, the efficacy of Duolac ATP, a probiotic preparation, was determined in a mouse model with AD-like skin lesions. Alterations in the cytokine levels and histological staining suggested the alleviation of AD. The in vivo test showed that T helper (Th)2 cytokines, IgE, interleukin (IL)-4, and IL-5, were significantly downregulated, whereas Th1 cytokines, IL-12p40 and interferon (IFN)-γ, were upregulated in all groups of mice treated with Duolac ATP compared to that observed in the group of mice treated with 1-chloro-2,4-dinitrobenzene (DNCB) alone. Moreover, the scratch score decreased in all mice treated with Duolac ATP. Staining of the dorsal area of the mice in each group with hematoxylin and eosin and toluidine blue further confirmed the alleviation of AD in mice orally treated with Duolac ATP. These results suggest that Duolac ATP inhibits the development of AD-like skin lesions in NC/Nga mice by suppressing the Th2 cell response and increasing the Th1 cell response. Thus, Duolac ATP is beneficial and effective for the treatment of AD-like skin lesions.

Late anastomotic leakage after low anterior resection in rectal cancer patients: clinical characteristics and predisposing factors

AIM

The purpose was to examine the clinical characteristics and predisposing factors of late anastomotic leakage following low anterior resection for rectal cancer.

METHOD

We retrospectively evaluated the clinicopathological features of patients who experienced anastomotic leakage after low anterior resection for rectal cancer. Patients were divided into two groups according to the time to leakage: early leakage (within 30 days postoperatively) and late leakage (after 30 days postoperatively). Clinicopathological characteristics were compared between the two groups.

RESULTS

Anastomotic leakage occurred in 141 patients. Anastomotic leakage was diagnosed at a median of 17 (range 0-886) days postoperatively; 85 (60.3%) and 56 (39.7%) were categorized as the early and late leakage groups, respectively. Radiotherapy (hazard ratio 5.007; 95% CI 2.208-11.354; P < 0.0001) was the only significant independent predisposing factor for late leakage. Diverting stoma did not protect against late leakage. The late leakage group more frequently had the fistula type (46.4% vs. 10.6%; P < 0.001) and less frequently needed laparotomy (55.4% vs. 78.8%; P = 0.001). The rate of long-term stoma over 1 year was greater in the late leakage than the early leakage group (51.8% vs. 29.4%; P = 0.009).

CONCLUSION

Late anastomotic leakages that develop after 30 days following low anterior resection are not uncommon and may be associated with the use of radiotherapy. Late leakage should be a different entity from early leakage in terms of the type of leakage, methods of management and subsequent sequelae.

Clinical implications of mucinous components correlated with microsatellite instability in patients with colorectal cancer

AIM

Colorectal cancer (CRC) with microsatellite instability (MSI) is characterized by frequent poor differentiation or mucinous histology. The purpose of this study was to evaluate the association of MSI with clinicopathological features and the oncological outcome in patients with a mucinous component.

METHOD

CRC tissue samples were analysed for histology and MSI. Patients were grouped according to the mucinous content of the tumour, as follows: > 50%, mucinous adenocarcinoma (MA); ≤ 50%, adenocarcinoma with mucinous component (AMC); none, nonmucinous adenocarcinoma (NMA). Clinicopathological parameters and survival were compared between patient groups.

RESULTS

Of 2025 patients, 84 (4%) had MA and 124 (6%) had AMC. In addition, 202 (10%) had MSI. Patients with MA and AMC tended to have a younger age of onset, right-colon predilection, large-sized tumour and high frequency of MSI compared with those with NMA (P < 0.001). MA and AMC patients with MSI showed a trend towards right-colon predilection and infrequent lymph-node metastasis compared with those with microsatellite stability (MSS; P = 0.005-0.03). There were no survival differences between the three groups, but patients with MSI-MA demonstrated lower 4-year recurrence and better overall survival rates than those with MSS-MA (P = 0.018 and P = 0.046, respectively).

CONCLUSION

Clinicopathological features of AMC and MA were similar and closely associated with MSI status. Although the prognoses of AMC and MA were no different from that of NMA, survival of patients with an MSI-MA tumour was significantly better than for those with MSS-MA tumours.

Tetrafluoroethane (R134a) hydrate formation within variable volume reactor accompanied by evaporation and condensation

Vast size hydrate formation reactors with fast conversion rate are required for the economic implementation of seawater desalination utilizing gas hydrate technology. The commercial target production rate is order of thousand tons of potable water per day per train. Various heat and mass transfer enhancement schemes including agitation, spraying, and bubbling have been examined to maximize the production capacities in scaled up design of hydrate formation reactors. The present experimental study focused on acquiring basic knowledge needed to design variable volume reactors to produce tetrafluoroethane hydrate slurry. Test vessel was composed of main cavity with fixed volume of 140 ml and auxiliary cavity with variable volume of 0 ∼ 64 ml. Temperatures at multiple locations within vessel and pressure were monitored while visual access was made through front window. Alternating evaporation and condensation induced by cyclic volume change provided agitation due to density differences among water and vapor, liquid and hydrate R134a as well as extended interface area, which improved hydrate formation kinetics coupled with latent heat release and absorption. Influences of coolant temperature, piston stroke/speed, and volume change period on hydrate formation kinetics were investigated. Suggestions of reactor design improvement for future experimental study are also made.

Improvement of atopic dermatitis-like skin lesions by IL-4 inhibition of P14 protein isolated from Lactobacillus casei in NC/Nga mice

Atopic dermatitis (AD) is a chronic inflammatory skin disease, with a complex etiology encompassing immunologic responses. AD is frequently associated with elevated serum immunoglobulin (Ig) E levels and is exacerbated by a variety of environmental factors, which contribute to its pathogenesis. However, the etiology of AD remains unknown. Recently, reports have documented the role of lactic acid bacteria (LAB) in the treatment and prevention of AD in humans and mice. The LAB, Lactobacillus casei (LC), is frequently used in the treatment of AD. To identify the active component of LC, we screened fractions obtained from the ion exchange chromatography of LC extracts. Using this approach, we identified the candidate protein, P14. We examined whether the P14 protein has anti-atopic properties, using both in vitro and in vivo models. Our results showed that the P14 protein selectively downregulated serum IgE and interleukin-4 cytokine levels, as well as the AD index and scratching score in AD-like NC/Nga mice. In addition, histological examination was also effective in mice. These results suggest that the P14 protein has potential therapeutic effects and that it may also serve as an effective immunomodulatory agent for treating patients with AD.

A Probiotic Preparation Duolac-Gold Ameliorates Dextran Sulphate Sodium-induced Mouse Colitis by Downregulating the Expression of IL-6

Probiotics are live microorganisms that confer a health benefit on the host. Duolac-Gold is a mixture of six probiotic bacteria containing three species of Bifidobacteria, two species of Lactobacillus, and Streptococcus thermophilus [corrected]. The aim of this study was to assess the anti-inflammatory effects of Duolac-Gold in an inflammatory bowel disease (IBD) mouse model. IBD was induced by administering 1.5% dextran sulfate sodium (DSS) for 10 days. After induction of DSS-induced colitis, Duolac-Gold was orally administered at three different concentrations. Interestingly, Duolac-Gold treatment accelerated IBD healing, and anti-inflammatory activity was assessed by weight loss, length of the colon, and a microscopic damage score by histology. The expression of inflammatory related cytokines was measured in colon tissues and serum. Of these cytokines, the expression of interleukin-6 decreased remarkably after Duolac-Gold treatment. Taken together, these results suggest that Duolac-Gold treatment is effective in IBD healing by regulating IL-6.

Gender and age differences in the impact of overweight on obesity-related quality of life among Korean adults

SUMMARY

OBJECTIVE

To investigate gender and age difference in impact of overweight on health-related quality of life (HRQOL) among Korean adults.

METHODS

Cross-sectional obesity-related quality of life (QOL) scores were measured by a Korean obesity-related QOL scale (KOQOL) from 448 Korean adults aged 20-80 years. A body mass index (BMI) was categorized with normal-weight as BMI < 23 kg/m(2), overweight as BMI ≥ 23 kg/m(2) based on the alternative cutoff points for Asians. Each gender was respectively stratified by median age, 45 years for men and 50 years for women, to examine the obesity-related QOL by age groups.

RESULTS

Women had a poorer obesity-related QOL compared to men (p < 0.001). In the younger age group, overweight women had a poorer obesity-related QOL compared with normal-weight women (p < 0.001), however normal-weight and overweight men showed no difference in obesity-related QOL. In the older age group, overweight men showed better QOL on the domains of work-related and psychosocial health than those for normal-weight men, but overweight women still suffered from work-related and routine life QOL.

CONCLUSIONS

This study showed the impact of overweight on obesity-related QOL was different for gender and age group. We should consider the results to manage weight in overweight persons.

A study on the prevention of salmonella infection by using the aggregation characteristics of lactic Acid bacteria

Salmonella is one of the major pathogenic bacteria that cause food poisoning. This study investigated whether heat-killed as well as live Lactobacillus protects host animal against Salmonella infection. Live and heat-killed Lactobacillusacidophilus was administered orally to Sprague-Dawley rats for 2 weeks before the rats were inoculated with Salmonella. Rise in body temperature was moderate in the group that was treated with heat-killed bacteria as compared to the Salmonella control group. The mean amount of feed intake and water consumption of each rat in the heat-killed bacteria group were nearly normal. The number of fecal Salmonellae was comparable between the live and the heat-killed L. acidophilus groups. This finding shows that L. acidophilus facilitates the excretion of Salmonella. Moreover, the levels of pro inflammatory cytokines, including tumor necrosis factor (TNF)-alpha and interleukin (IL)-1 beta, in the heat-killed L. acidophilus group were significantly lower when compared to the levels in the Salmonella control group. These results indicate that nonviable lactic acid bacteria also could play an important role in preventing infections by enteric pathogens such as Salmonella.

Femur-mounted navigation system for the arthroscopic treatment of femoroacetabular impingement

Femoroacetabular impingement stems from an abnormal shape of the acetabulum and proximal femur. It is treated by resection of damaged soft tissue and by the shaping of bone to resemble normal features. The arthroscopic treatment of femoroacetabular impingement has many advantages, including minimal incisions, rapid recovery, and less pain. However, in some cases, revision is needed owing to the insufficient resection of damaged bone from a misreading of the surgical site. The limited view of arthroscopy is the major reason for the complications. In this research, a navigation method for the arthroscopic treatment of femoroacetabular impingement is developed. The proposed navigation system consists of femur attachable measurement device and user interface. The bone mounted measurement devices measure points on head-neck junction for registration and position of surgical instrument. User interface shows the three-dimensional model of patient's femur and surgical instrument position that is tracked by measurement device. Surgeon can know the three-dimensional anatomical structure of hip joint and surgical instrument position on surgical site using navigation system. Surface registration was used to obtain relation between patient's coordinate at the surgical site and coordinate of three-dimensional model of femur. In this research, we evaluated the proposed navigation system using plastic model bone. It is expected that the surgical tool tracking position accuracy will be less than 1 mm.

Non-invasive in situ plasma monitoring of reactive gases using the floating harmonic method for inductively coupled plasma etching application

The floating harmonic method was developed for in situ plasma diagnostics of allowing real time measurement of electron temperature (Te) and ion flux (Jion) without contamination of the probe from surface modification by reactive species. In this study, this novel non-invasive diagnostic system was studied to characterize inductively coupled plasma of reactive gases monitoring Te and Jion for investigating the optimum plasma etching conditions and controlling of the real-time plasma surface reaction in the range of 200-900 W source power, 10-100 W bias power, and 3-15 mTorr chamber pressure, respectively.

Distal metatarsal osteotomy for hallux varus following surgery for hallux valgus

We reviewed the outcome of distal chevron metatarsal osteotomy without tendon transfer in 19 consecutive patients (19 feet) with a hallux varus deformity following surgery for hallux valgus. All patients underwent distal chevron metatarsal osteotomy with medial displacement and a medial closing wedge osteotomy along with a medial capsular release. The mean hallux valgus angle improved from -11.6° pre-operatively to 4.7° postoperatively, the mean first-second intermetatarsal angle improved from -0.3° to 3.3° and the distal metatarsal articular angle from 9.5° to 2.3° and the first metatarsophalangeal joints became congruent post-operatively in all 19 feet. The mean relative length ratio of the metatarsus decreased from 1.01 to 0.99 and the mean American Orthopaedic Foot and Ankle Society score improved from 77 to 95 points. In two patients the hallux varus recurred. One was symptom-free but the other remained symptomatic after a repeat distal chevron osteotomy. There were no other complications. We consider that distal chevron metatarsal osteotomy with a medial wedge osteotomy and medial capsular release is a useful procedure for the correction of hallux varus after surgery for hallux valgus.

Validation of the seventh edition of the American Joint Committee on Cancer tumor-node-metastasis (AJCC TNM) staging in patients with stage II and stage III colorectal carcinoma: analysis of 2511 cases from a medical centre in Korea

AIM

The sixth and seventh editions of the American Joint Committee on Cancer (AJCC) tumor-node-metastasis (TNM) system for patients with stage II and stage III colorectal carcinoma (AJCC-6 and AJCC-7) were compared.

METHOD

Between 2000 and 2007, 2511 stage II/III colorectal carcinoma patients received primary surgical resection at the Asan Medical Center (Seoul, Korea). All patients were staged using AJCC-6 and AJCC-7 TNM systems. Patients with synchronous or other cancers, those given preoperative chemotherapy or radiotherapy and those in whom fewer than 12 lymph nodes were resected, were excluded. Overall survival (OS) and disease-free survival (DFS) were compared.

RESULTS

Of 2511 patients, 255 (10.2%) had different stages in the AJCC-6 and AJCC-7. For the AJCC-7, the 5-year OS by stage was 94.2% for stage IIA, 88.8% for stage IIB, 83.5% for stage IIC, 91.8% for stage IIIA, 81.8% for stage IIIB and 72.0% for stage IIIC. The OS and the DFS were not significantly different for the new substages IIB (n = 57) and IIC (n = 34) (P = 0.34 and P = 0.87, respectively). For the 187 patients with stage T3N2a cancer, the OS and the DFS were significantly different from stage IIIB other than T3N2a (P = 0.008 and P = 0.01, respectively) and there were no statistically significant differences in OS between the T3N2a group and the IIIC group (P = 0.46).

CONCLUSION

The study indicates that AJCC-7 has better prognostic validity than AJCC-6 for staging of patients with stage II and stage III colorectal carcinoma.

Metabolic syndrome and quality of life (QOL) using generalised and obesity-specific QOL scales

OBJECTIVES

We investigated the association between metabolic syndrome (MS) and health-related quality of life (HRQOL) assessed using generalised and obesity-specific QOL instruments.

METHODS

We recruited 456 outpatients [age: 19-81 years, body mass index (BMI): 16.3-36.7 kg/m2] in the primary care division from 12 general hospitals in Korea. HRQOL was measured using EuroQol comprising the health states descriptive system (EQ-5D) and visual analogue scale (EQ-VAS) as a general instrument. The Korean Obesity-related QOL scale (KOQOL) composed of six domains was used as a disease-specific QOL instrument. MS was defined on the basis of International Diabetes Federation (IDF) criteria with Korean-specific waist circumference cutoffs (men: 90 cm, women: 85 cm).

RESULTS

Subjects with MS displayed significantly higher impairment of EQ-5D and KOQOL. Binary logistic regression analysis of MS patients with controls for age, gender, smoking, alcohol, exercise, education, income, marital status and medication history disclosed odds ratio (OR) values of 2.13 (1.33-3.41) for impaired total KOQOL, 2.07 (1.31-3.27) for impaired physical health, 1.63 (1.03-2.60) for impaired work-related health, 2.42 (1.45-4.04) for impaired routine life, 2.08 (1.27-3.40) for impaired sexual life and 2.56 (1.59-4.11) for diet distress. Among the EQ-5D dimensions, only pain/discomfort displayed a significantly increased OR of 1.60 (1.01-2.56) in MS group.

CONCLUSIONS

Subjects with MS displayed a significantly impaired HRQOL compared with those without MS. MS and HRQOL were more strongly associated in obesity-specific QOL than in generalised QOL.

Recollapse of previous vertebral compression fracture after percutaneous vertebroplasty

This study was undertaken to investigate the incidence rate, characteristics, and predisposing factors associated with recollapse of the same vertebrae after percutaneous vertebroplasty (PVP). Recollapse of the same vertebra after PVP is the one of the complications of the procedure, and the incidence rate in our study was 3.21%. The most important predisposing factor was pre-operative osteonecrosis. Recollapse was not related to trauma.

INTRODUCTION

PVP using polymethylmethacrylate has become a popular treatment for osteoporotic vertebral compression fracture. Recollapse of the same vertebrae after PVP has rarely been reported. This study was undertaken to investigate the incidence, characteristics, and predisposing factors associated with recollapse of the same vertebrae after PVP.

METHODS

Eleven patients (seven females and four males; mean age, 69.91 +/- 5.49 years), out of a total of 343 patients, developed recollapse of the same vertebra after PVP. The 11 patients who developed recollapse comprised the "recollapse group", while the remaining 332 patients comprised the "well-maintained group".

RESULTS

Pre-operative magnetic resonance imaging revealed that the incidence of osteonecrosis was significantly higher in the recollapse group than the well-maintained group (p < 0.05). The degree of re-expansion of the compressed vertebral body after PVP was significantly higher in the recollapse group than in the well-maintained group (p < 0.05).

CONCLUSIONS

The most important predisposing factor for recollapse was pre-operative osteonecrosis. Recollapse was not related to trauma. Osteoporotic vertebral compression fracture with osteonecrosis or pseudoarthrosis has been regarded as a relative indication for PVP; however, the findings of this study suggest that this disease category may be a relative contraindication for PVP.

Gamma knife radiosurgery for medically refractory idiopathic trigeminal neuralgia

Gamma knife radiosurgery (GKS) has been generally considered as a viable therapeutic option for the management of medically refractory idiopathic trigeminal neuralgia (TN). We reviewed our experience with GKS in patients with TN. Between Feb 1996 and May 2006, 77 patients with medical refractory idiopathic TN were treated using GKS. Thirty-six patients who had undergone other previous procedures, previous GKS, or had brain stem lesion, atypical symptoms, were excluded from this study. Pain improvement was achieved in 38 of the patients with TN (pain response rate 92.7%). Twenty-three patients were pain free and 15 had reduced pain. There were no serious complications. We think that GKS is an effective treatment option for patients with medical refractory idiopathic TN.

AAV-GAD gene for rat models of neuropathic pain and Parkinson's disease

The introduction of therapeutic genes to neurons by genetic modification has potential as an effective treatment for CNS disorders for all that a successful clinical application has not yet been fully implemented. In this paper, we will discussed the role of AAV vectors with the GAD65 gene for animal models of PD and neuropathic pain. AAV vector is one of the most attractive gene delivery vehicles for direct introduction of therapeutic genes into the CNS in the treatment of neurological diseases. GAD65 is present as a membrane-associated form in synapses and is primarily involved in producing synaptic gamma-aminobutyric acid (GABA) for vesicular release. We constructed rAAV-GAD65 expressing rat GAD65 and demonstrated that rat Parkinsonian symptoms can be significantly improved concomitantly with the production of GAD65. We also demonstrated rAAV-GAD65 as a successful gene delivery vehicle in a chronic pain model by administrating rAAV-GAD65 to DRGs because GABA driven by GAD is a major inhibitory neurotransmitter in the dorsal horn of the spinal cord and also plays an important role in the ventral horn. We believe that AAV vectors can be excellent candidates for gene therapy of neurological diseases.

Predictors of persistent airway stenosis in patients with endobronchial tuberculosis

SETTING

The university and municipal hospitals in Seoul, Korea.

OBJECTIVE

To evaluate the predictors of persistent airway stenosis following anti-tuberculosis chemotherapy in patients with endobronchial tuberculosis (TB).

DESIGN

Diagnosis of TB was confirmed by microbiology or histopathology. Bronchoscopic examinations revealed that patients had endobronchial lesions compatible with endobronchial TB. Study subjects had at least one follow-up bronchoscopy to evaluate their treatment response. Treatment response was determined by changes in the degree or extent of airway stenosis between the first and last bronchoscopic examinations.

RESULTS

Sixty-seven subjects were recruited retrospectively from Seoul National University Hospital and Seoul National University Boramae Hospital. Persistent bronchostenosis occurred in 41.8% of the patients. In multivariate regression analysis, age >45 years (OR 3.65), pure or combined fibrostenotic subtype (OR 5.54) and duration from onset of chief complaint to the initiation of anti-tuberculosis chemotherapy >90 days (OR 5.98) were identified as independent predictors of persistent airway stenosis. Oral corticosteroids (prednisolone equivalent >or=30 mg/d) did not reduce the frequency of persistent airway stenosis.

CONCLUSION

Early diagnosis and early administration of anti-tuberculosis chemotherapy before involvement of the deeper airways is important to prevent the development of unwanted sequelae of bronchostenosis.

Prevalence of osteoporosis in patients requiring spine surgery: incidence and significance of osteoporosis in spine disease

The purpose of this study is to evaluate the incidence of osteoporosis in patients requiring spine surgery. Among patients older than 50 years, the rate of osteoporosis in males was 14.5% and the rate osteoporosis in females was 51.3%. We strongly recommend an evaluation and treatment for osteoporosis in the patients requiring spine surgery, especially in females over 50 years old.

INTRODUCTION

Because lifespan is increasing, there is an increase in the incidence of osteoporosis in elderly spine surgery patients. The osteoporosis may adversely influence the fusion rate and the surgical outcome. The purpose of this study is to evaluate the incidence of osteoporosis in patients requiring spine surgery.

METHODS

A total of 1,321 patients underwent spine surgeries at our institute from January 1, 2005 to December 31, 2005. Among them, there were 562 patients (42.5%) younger than 50 years old, and 759 patients (57.6%) older than 50 years old. Prior to operation, we evaluated the patients for osteoporosis on both the femur head and lumbar spine by measuring the bone mineral density (BMD) by the dual-energy X-ray absorptiometry (DXA). Based on the World Health Organization (WHO) criteria for osteoporosis, we chose the T-score to determine normal (>-1), osteopenia (-1>or=, >-2.5), and osteoporosis (<or=-2.5). Among the 562 patients younger than 50 years, DXA was performed in 22 (3.9%) patients and there were 13 (2.3%) cases of osteopenia and 2 (0.3%) cases of osteoporosis.

RESULTS

Among 759 patients older than 50 years, DXA was performed on 516 (68.0%) patients, 193 males and 323 females. Among the male patients, there were 89 (46.1%) patients with osteopenia and 28 (14.5%) with osteoporosis. Among the female patients, there were 134 (41.4%) with osteopenia and 166 (51.3%) with osteoporosis. The incidence of osteoporosis was higher in female patients and significantly increased with increasing age. Among 759 patients older than 50 years, 676 patients underwent a major spine operation with or without fusion. Among these patients, DXA was performed in 446 (66.0%) patients and there were 207 (46.4%) patients with osteopenia and 139 (31.1%) with osteoporosis.

CONCLUSIONS

The patients over 50 year-old who need spine operation have osteoporosis often. In conclusion, the number of spine operations in elderly patients is increasing and the incidence of osteoporosis in spine surgery patients is also increasing. We strongly recommend an evaluation for osteoporosis and post-operative treatment for osteoporosis in patients over 50 years old, especially for female patients.

The new definition of metabolic syndrome by the international diabetes federation is less likely to identify metabolically abnormal but non-obese individuals than the definition by the revised national cholesterol education program: the Korea NHANES study

OBJECTIVE

The new definitions for metabolic syndrome (MS) proposed by the IDF and revised NCEP have caused some confusion because patients have emerged that have satisfied the revised NCEP but not the IDF criteria. We performed this study to compare the prevalence of these criteria and to investigate the characteristics of discrepant cases.

RESEARCH DESIGN AND METHODS

A total of 7962 individuals aged >or= 20 years (3597 men; 4365 women) who participated in the 1998 Korean NHANES were included. We assessed the agreement between the revised NCEP and IDF criteria and investigated the characteristics of cases satisfying the revised NCEP criteria but not the IDF criteria.

RESULTS

The prevalence of MS by the revised NCEP (25.7% of men and 31.9% of women) was higher than that according to the IDF (14.2% of men and 26.6% of women). The IDF criteria failed to identify 44.9% of men and 16.6% of women identified as having MS according to the revised NCEP criteria. The discrepant group showed more adverse metabolic profiles and unfavorable lifestyles despite lower waist circumference as compared with those having MS by both the IDF and revised NCEP criteria. The prevalence of discrepant cases was higher among the elderly.

CONCLUSIONS

The IDF criteria were inferior to the revised NCEP criteria in identifying the metabolically abnormal but nonobese groups known to be predisposed to type 2 diabetes and cardiovascular disease. Further research regarding the appropriateness of central obesity as an obligatory criterion proposed by the IDF seems to be warranted.

Bone temperature estimation during orthopaedic round bur milling operations

Heat generation during orthopaedic bone cutting operations may cause thermal bone damage. During the bone cutting, the maximum temperature occurs at the point of contact between the bone and the cutting tool. However, this temperature is difficult to measure. Many researchers have attempted to measure this temperature using a thermocouple; however, limitations of the thermocouple makes it difficult to determine the maximum temperature at the point of contact. In order to solve this problem, in this study, two infrared thermometers are used to measure the fresh-milled surface temperature, and the maximum temperature was extrapolated by a moving plane heat source solution. The estimated maximum temperature increment varied from 49 to 115 degrees C under various cutting conditions. These results showed that the thermal damage may reach up to 1.9 mm in depth during round bur milling. A larger feed rate and a smaller cutting depth decreased the maximum temperature.

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

OBJECTIVE

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

DESIGN

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

RESULTS

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

CONCLUSION

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

Galanin-immunoreactive cells and their relation to calcitonin gene-related peptide-, substance P- and somatostatin-immunoreactive cells in rat lumbar dorsal root ganglia

We report upon the distribution of galanin-immunoreactive (GAL-IR) cells in the lumbar dorsal root ganglia (DRG) of the rat, and upon the distribution of GAL-IR cells, which also contain calcitonin gene-related peptide (CGRP)-, substance P (SP)- and somatostatin (SOM)-immunoreactivity. Neuropeptide-immunoreactive lumbar DRG cells were 55.8% for CGRP, 12.7% for SP, and 6.5% for GAL in lumbar DRG cells. There was no significant difference between the right and left DRGs (L1-L6) for any neuropeptide-immunoreactive cell (P < 0.01). In terms of size distribution, CGRP-immunoreactive cells were identified below 1500 microm2, and SP-, and GAL-IR cells below 600 microm2. Neuropeptide immunoreactive cells showed various immunoreactivities in the cytoplasm according to each neuropeptide. CGRP and SP immunoreactive cells were colocalized with GAL immunoreactive cells in the serial sections about 83.3 and 60% respectively, but SOM colocalizing with GAL-IR cells were not in evidence. The current results confirm and extend previous results, and show that neuropeptides can coexist in single sensory neurones of the rat DRG. In addition, our results demonstrate that the normal distribution of some neurotransmitters modulating sensory action in Wistar Kyoto rat, make this model more prone to develop neuropathic pain than Sprague-Dawley rat.

Age-related change of neuropeptide Y-immunoreactive neurons in the rat anterior olfactory nucleus

Neuropeptide Y (NPY) is located in the olfactory system, including the olfactory bulb, and is thought to be one of the main neurotransmitters for olfaction. Thus, we examined age-related changes of NPY-immunoreactive (IR) neurons in the rat anterior olfactory nucleus (AON) at various aging stages over a period of 2 years; postnatal months 1 (PM 1), PM 6, PM 12 and PM 24. NPY-IR neurons in the AON were present in the lateral and medial subdivisions at PM 1 and at PM 6 were distributed in all subdivisions of the AON. Prior to PM 12, the NPY-IR neurons showed a tendency to change from bipolar cells with short processes into multipolar cells with long processes. Moreover, the population of NPY-IR neurons and nerve fibers in the AON increased in proportion to age. In particular, the number of NPY-IR neurons increased about 6-fold between PM 1 and PM 3. At PM 24, the number of NPY-IR neurons was much smaller than that at PM 12 and somal size had decreased. It is therefore suggested that the dramatic increase in the number and size of the NPY-IR neurons between PM 1 and PM 3 may be associated with sexual maturation and that the decrease in the number and cell size of the NPY-IR neurons at PM 24 may underlie age-related changes in the olfactory process.

The role of functional MR imaging in patients with ischemia in the visual cortex

BACKGROUND AND PURPOSE

Functional MR (fMR) imaging is based on changes in regional blood flow. The purpose of this study was to evaluate the role of fMR imaging for detection of a vascular compromised status in the occipital lobe in patients with ischemia in the visual cortex.

METHODS

We performed fMR imaging in seven control subjects and seven patients with symptoms and signs of visual cortical transient ischemia and/or infarct. fMR imaging was performed using a gradient-echo sequence with the 2D fast low-angle shot technique. An axial slice including both visual cortices was selected, and stimulation of the visual cortex was performed using a red photostimulator. The number of activated pixels in each primary visual cortex area were counted and an asymmetry ratio [AR (%) = 100 x (R-L)/(R+L)/2] was calculated. Patients and control subjects underwent visual field examination, conventional MR imaging, and vascular imaging (MR angiography in all patients and control subjects, conventional catheter angiography in two patients). fMR imaging results were compared with the results of a visual field examination, conventional MR imaging, and vascular imaging.

RESULTS

fMR imaging of the patients showed significant activation asymmetry (P <.05) compared with that of control subjects. Vascular abnormalities in the posterior circulation were found in all seven patients. By conventional MR imaging, five patients were found to have infarction in the occipital lobe and the remaining two patients showed no abnormality. In visual field examination, six of the seven patients showed homonymous hemi- or quadrantanopsia suggesting postchiasmic abnormalities, and the remaining patient had normal findings. fMR imaging showed decreased activity in the visual cortices corresponding to vascular abnormalities (seven of seven patients), permanent infarction (five of seven patients), or visual field defect (six of seven patients). Two patients with normal conventional MR imaging had vascular lesions in the posterior circulation, and fMR imaging showed decreased activity in the corresponding visual cortices. One patient with normal visual field examination had multifocal stenosis in the posterior cerebral artery without infarction, and fMR imaging showed decreased activity in the corresponding visual cortex.

CONCLUSION

fMR imaging of the visual cortex may be a sensitive method for the detection of vascular-compromised status in the occipital lobe.

Systematic methodology for the design of a flexible keel for energy-storing prosthetic feet

An effective design method is suggested for a flexible keel design for energy-storing prosthetic feet (ESPF). The basic, two-dimensional shape of the keel is based on anthropometric data and normal gait analysis available in the literature. Cost function is defined for the performance evaluation of the keel. Five factors and five levels of their effect on the performance of the keel are established. By use of an orthogonal array table, 25 trials of dynamic simulations of prosthetic walking are designed, from among 3,125 possible combinations, dramatically reducing the number of total simulations needed to examine sufficiently the contribution of each factor to cost function. A prosthetic walking model is built, and a dynamic simulation of prosthetic walking is performed using the finite element method. The contribution of each factor to cost function is investigated by an analysis of variance (ANOVA), and the average main effects of factors for cost function are calculated. The optimum combination of factor levels is obtained by minimisation of cost function. To examine the structural safety of the keel, the deformation and stress distribution of the keel are investigated by static analysis, and failure indices are calculated by three failure criteria. Finally, the optimum flexible keel is designed with increased energy storage capacity, without failure, and suitable for more active prosthetic walking; the recoverable strain energy stored in the optimum ESPF keel is 25.8J.

Morphological structure of accessory spleen in Chinese hamsters

To attempt a rigorous definition of the structure of the accessory spleen (AS) in the Chinese hamster, we examined twenty-one animals, and found AS in 5 animals (23.8%), which were over 7-month-old. The AS had no connection with the main spleen and was seen as a dark red oval organ (0.7 mm x 1.5 mm), which was embedded in the adipose tissue near the tail of the pancreas. It was demarcated from the adipose tissue and some pancreatic tissue. The organ was encapsulated by thin collagenous connective tissue and smooth muscle fibers, and contained lymphatic nodules, reticular fibers, nodular central arterioles, macrophages and megakaryocytes. Notably the incidence of AS appeared to increase with age in the Chinese hamsters.

Carotid artery stenting in patients with symptomatic coronary artery disease

Carotid artery stenting has been accepted as a potential alternative to carotid endarterectomy in patients with significant carotid artery stenosis. The objective of this study was to evaluate the feasibility, safety and long-term outcome of percutaneous stenting of carotid artery stenosis in patients with coexisting symptomatic coronary disease. Between May 1996 and May 1999, we performed carotid artery stenting at 48 lesions in 36 patients with carotid stenosis of 60% and symptomatic coronary artery stenosis. Twenty-one patients (58%) had neurologic symptoms. Carotid stenting was performed in 43 internal, 2 external and 3 common carotid lesions. We used Wallstent in 46 lesions, Palmaz stent in 2 lesions and Microstent II in 1 lesion. Staged or combined coronary intervention was performed in 18 patients (50%) and staged coronary artery bypass surgery was performed in 6 patients (17%). In the other 12 patients (33%), medical treatments were performed. Carotid stenting was successful in all lesions. Simultaneous bilateral carotid stenting was performed in 11 patients (31%). One major and 1 minor stroke developed during the procedure. There were no deaths during the procedures and within 30 days post-procedure. During the follow-up of 14 +/- 7 (3 to 40) months, there were no deaths or neurological events. On follow-up (6 +/- 1 months) angiography and/or duplex sonography of 44 eligible lesions in 32 patients, there were 2 cases of asymptomatic restenosis (4.5%) which developed in Palmaz stents implanted at the external carotid artery and the common carotid artery, respectively. In conclusion, carotid artery stenting in patients with coexistent carotid and coronary artery disease is feasible, safe and shows favorable follow-up outcomes.

Transseptal approach for stent implantation in right internal carotid artery stenosis

Carotid artery stenting is emerging as an effective measure to prevent strokes in patients with significant carotid artery stenosis. We report a case of right internal carotid artery stenosis in which we used a transseptal approach for successful carotid artery stenting. This patient had concomitant stenosis at all three coronary arteries, including the left main coronary artery. A transseptal approach was adopted due to the sharply angled take-off of the right brachiocephalic artery from the tortuous aortic arch, where advancement of an extra-stiff wire into the right common carotid artery was not possible by a femoral artery approach.

Effect of 7-nitroindazole, a selective neuronal nitric oxide synthase inhibitor, on parvalbumin immunoreactivity after cerebral ischaemia in the hippocampus of the Mongolian gerbil

Previous studies have demonstrated that a loss of parvalbumin-immunoreactive (PV-ir) neurones is observed in the hippocampus after transient cerebral ischaemia. However, whether the loss of parvalbumin (PV) immunoreactivity is related to the over-production of nitric oxide (NO) during cerebral ischaemia has not been evaluated. This study was designed to test the effect of 7-nitroindazole pre-treatment (7-NI, 50 mg/kg), a selective neuronal NO synthase inhibitor, on PV immunoreactivity and its cellular activity following forebrain ischaemia. PV-ir neurones in the hippocampus of the control group were widely distributed in the pyramidal cell layer and stratum oriens of CA1 and CA3, and the granular cell layer of dentate gyrus. 7-NI pre-treatment completely suppressed the reduction of PV immunoreactivity in CA1 that was observed in the ischaemia-induced group. Subsequently, 7-NI pre-treatment also protected against the structural loss of microtubule-associated protein 2 (MAP2) immunoreactivity in CA1 after ischaemic insult. In addition, the Fos-defined neuronal activity of PV-ir neurones was slightly increased by the 7-NI pre-treatment 3 h after ischaemia. Based on these data, we conclude that the neuronal toxicity of NO may be involved in the loss of PV-ir neurones after cerebral ischaemia.

Regulation of NeuroD expression by activation of the protein kinase-C pathway in Y79 human retinoblastoma cells

To examine the signals that regulate NeuroD expression, we analyzed the effects of activation of two major signal pathways, the protein kinase A (PKA) pathway and the protein kinase C (PKC) pathway, on the expression of NeuroD in Y79human retinoblastoma cells. Activation of PKC resulted in marked induction of NeuroD mRNA and NeuroD protein. NeuroD mRNA induction was inhibited by calphostin C, an inhibitor of PKC. On the other hand, stimulation of PKA by forskolin had a weak suppressive effect on NeuroD mRNA expression. Induction of NeuroD expression was followed by enhancement of expression of the AK1 gene, one of the target genes of NeuroD, which encodes adenylate kinase isozyme 1, an important enzyme in the cellular adenine nucleotide homeostasis. Our results indicate that NeuroD expression is regulated, at least in part, by the PKC pathway and not by the PKA pathway.

Overexpression of NeuroD in PC12 cells alters morphology and enhances expression of the adenylate kinase isozyme 1 gene

NeuroD, a basic helix-loop-helix transcription factor, plays an important role in neuronal differentiation. A rat NeuroD cDNA was obtained by the aid of reverse transcription-polymerase chain reaction (RT-PCR) and ligated to an expression vector having a CMV promoter. Transfection of the NeuroD-expression plasmid into PC12 cells, a rat pheochromocytoma cell line, induced morphological changes featured by neurite-like processes and synapse-like structures without a differentiation-inducing reagent such as NGF. In the transfected cells, the overproduced NeuroD was detected by Western blot analysis, and the expression of the gene encoding mid-sized neurofilaments, a neuron-specific marker, was demonstrated by RT-PCR. Adenylate kinase isozyme 1 (AK1) is an enzyme involved in the homeostasis of energy metabolism and appears specifically in neuronal cells during differentiation. The CAT reporter assay of the 5'-flanking region of the AK1 gene suggests that NeuroD activates the AK1 expression through E-boxes in the promoter region. RT-PCR analysis indicated the enhanced level of AK1 mRNA in NeuroD-producing PC12 cells. Electrophoretic mobility shift assays demonstrated that NeuroD was able to interact with a proximal E-box element of the AK1 promoter. The results indicated that NeuroD promoted the PC12 cells to differentiate into neuron-like cells with concomitant activation of the target genes including the AK1 and the neurofilament genes.

Molecular cloning and characterization of the gene encoding human NeuroD

NeuroD is a basic helix-loop-helix transcription factor that binds to an E-box sequence, CANNTG, in the target gene promoter region. The gene encoding NeuroD is expressed specifically in brain, intestine, and pancreatic cells and plays a pivotal role in tissue-specific differentiation. To investigate the regulation of human NeuroD gene expression, we isolated and sequenced a genomic DNA containing two exons and flanking regions of the NeuroD gene. The sizes of exons 1 and 2 were 168 and 2404 bp, respectively. CAT reporter analysis showed that the elements responsible for basal promoter activity lay in the proximal 408-bp region. Cotransfection of the CAT reporter plasmids with a NeuroD expression plasmid resulted in 5-fold enhancement of the CAT activity, indicating an autoregulatory mechanism is involved in human NeuroD gene expression.

cDNA cloning and tissue-specific expression of the gene encoding human adenylate kinase isozyme 2

We isolated two kinds of cDNAs encoding human adenylate kinase (AK) isozyme 2 from a HeLa cell cDNA library using bovine AK2 cDNA as a probe. Nucleotide sequencing revealed that the cDNAs encoded 239- and 232-amino acid proteins with deduced molecular mass of 26.5 (AK2A) and 25.6kDa (AK2B), respectively. Northern blot analysis demonstrated that AK2 mRNA is strongly expressed in liver, heart, skeletal muscle and pancreas, and moderately in kidney, placenta and brain, and weakly in lung. However, Western blot analysis showed that AK2 protein was present in large amounts in liver, heart, kidney, and in a small amount in lung, and undetectable in brain and skeletal muscle. These results suggested the presence of the tissue-specific gene-expression including post-transcriptional regulation in expression of the AK2 gene.

Low-frequency response of pyroelectric sensors

Sensitivity of pyroelectric IR-detectors of slow thermal processes, especially of human body sensors, depends strongly on their response in the infra-low (~0.1 to 1 Hz) region of frequency spectrum. The main mechanisms of heat losses-heat conduction of environment, lateral heat conduction in the plane of sensitive element, and emission of radiation-are considered. Their influence on the low-frequency response of pyroelectric sensors is estimated. Exact solutions and simple expressions for quantitative description of main specific features of real systems are obtained. Criteria of validity of the adequate models are determined.

Frequency response of multilayer pyroelectric sensors

The pyroelectric response of the multilayer system consisting of the front surroundings, the pyroelectric element, the intermediate layer, and the back surroundings is calculated. The general expression and simple relations are obtained between main geometric and thermophysical parameters of the system under consideration and characteristics of the pyroelectric response in a large variety of configurations of pyroelectric sensors, such as detectors with the pyroelectric element in a gas, detectors without air gap as well as detectors with air gap between the element and the substrate, and detectors in immersion systems, etc. In particular, it is shown that, for the detectors with air gap, the wide flat part of the frequency response appears with any properties of substrate if the double thermal resistance of the air gap exceed that of the pyroelectric element, whereas for the detectors without air gap it appears only if the substrate has relatively large complex thermal conductivity.

Modulation of protein kinase C activity in NIH 3T3 cells by plant glycosides from Panax ginseng

The involvement of ginsenosides in the signal cascade that stimulates cellular growth was investigated. It was found that ginsenosides Rh1 and Rh2 extracted from the root of Panax ginseng inhibited cellular proliferation in NIH 3T3 fibroblasts. Both ginsenosides Rh1 and Rh2 effectively reduced phospholipase C activity resulting in a decrease in the intracellular level of diacylglycerol, an endogenous activator of protein kinase C. The treatment of cells with Rh1 or Rh2 was thus found to reduce intracellular protein kinase C activity. We also observed that the phosphorylation of myristoylated alanine-rich C kinase substrate, one of the major substrates of protein kinase C in cells, was inhibited by the ginsenosides. Data suggest that the ginsenoside Rh1 or Rh2 exerts antiproliferative effects by inhibiting phospholipase C, which produces second messengers necessary for the activation of protein kinase C.

A prospective study of the accuracy of clinical examination evaluated by arthroscopy of the knee

The diagnostic accuracy of clinical examination for internal derangement of the knee were evaluated by arthroscopy in 195 patients (200 knees). Radiographs were available and 50 patients had magnetic resonance imaging. The clinical diagnosis was correct in 104 knees (52%), incomplete in 70 (35%) and incorrect in 26 (13%). When there was a single abnormality the diagnosis was correct in 70%, but when more than 3 lesions were discovered the figure was 28%. All individual lesions were diagnosed correctly in more than 90%. The lesions most difficult to diagnose were chondral fractures, partial tears of the anterior cruciate ligament and loose bodies. Knees with acute lesions and those with a single diagnosis were significantly easier to diagnose (p < 0.01). Age, sex, MRI and the surgeon were not significant.

Factors on graft survival of living donor kidney transplantation in a single center

We analyzed the potential factors that could influence the survival of graft, focused on primary graft living-donor kidney transplantation with cyclosporine (CsA) therapy. 680 cases were enrolled in this study. Patients and graft survival rates were calculated by a Kaplan-Meier product limit estimate with a 1-day time interval. The analyzed variables were donor relationship, HLA matching, recipient age and sex, donor age and sex, ABO blood type compatibility, diabetic status, hepatitis virus infection, donor specific or non-specific blood transfusion and acute rejection episode. The results suggested that acute rejection episode was the most prognostic factor in graft survival. An HLA-matched donor and a young male donor, i.e. a greater donor nephron mass for less recipient body mass, will show better long-term survival. Diabetes and hepatitis B infection have some negative effects on the long-term survival of graft kidney, but age of recipient, donor-specific transfusion and donor-recipient relationship have little effect.

Poly(ADP-ribosyl)ation of histone H1 correlates with internucleosomal DNA fragmentation during apoptosis

The biochemical role of poly(ADP-ribosyl)ation on internucleosomal DNA fragmentation associated with apoptosis was investigated in HL 60 human premyelocytic leukemia cells. It was found that UV light and chemotherapeutic drugs including adriamycin, mitomycin C, and cisplatin increased poly(ADP-ribosyl)ation of nuclear proteins, particularly histone H1. A poly(ADP-ribose) polymerase inhibitor, 3-aminobenzamide, prevented both internucleosomal DNA fragmentation and histone H1 poly(ADP-ribosyl)ation in cells treated with the apoptosis inducers. When nuclear chromatin was made accessible to the exogenous nuclease in a permeabilized cell system, chromatin of UV-treated cells was more susceptible to micrococcal nuclease than the chromatin of control cells. Suppression of histone H1 poly(ADP-ribosyl)ation by 3-aminobenzamide reduced the micrococcal nuclease digestibility of internucleosomal chromatin in UV-treated cells. These results suggest that the poly(ADP-ribosyl)ation of histone H1 correlates with the internucleosomal DNA fragmentation during apoptosis mediated by DNA damaging agents. This suggestion is supported by the finding that xeroderma pigmentosum cells which are defective in introducing incision at the site of DNA damage, failed to induce DNA fragmentation as well as histone H1 poly(ADP-ribosyl)ation after UV irradiation. We propose that poly(ADP-ribosyl)ation of histone H1 protein in the early stage of apoptosis facilitates internucleosomal DNA fragmentation by increasing the susceptibility of chromatin to cellular endonuclease.