Discovery of N-benzylbenzamide-based allosteric inhibitors of Aurora kinase A

Aurora kinases (AurkA/B/C) regulate the assembly of bipolar mitotic spindles and the fidelity of chromosome segregation during mitosis, and are attractive therapeutic targets for cancers. Numerous ATP-competitive AurkA inhibitors have been developed as potential anti-cancer agents. Recently, a few allosteric inhibitors have been reported that bind to the allosteric Y-pocket within AurkA kinase domain and disrupt the interaction between AurkA and its activator TPX2. Herein we report a novel allosteric AurkA inhibitor (6h) of N-benzylbenzamide backbone. Compound 6h suppressed the both catalytic activity and non-catalytic functions of AurkA. The inhibitory activity of 6h against AurkA (IC50 = 6.50 μM) was comparable to that of the most potent allosteric AurkA inhibitor AurkinA. Docking analysis against the Y-pocket revealed important pharmacophores and interactions that were coherent with structure-activity relationship. In addition, 6h suppressed DNA replication in G1-S phase, which is a feature of allosteric inhibition of AurA. Our current study may provide a useful insight in designing potent allosteric AurkA inhibitors.

Perioperative outcomes of laparoscopic low anterior resection using ArtiSential® versus robotic approach in patients with rectal cancer: a propensity score matching analysis

BACKGROUND

Total mesorectal excision using conventional straight fixed devices may be technically difficult because of the narrow and concave pelvis. Several laparoscopic articulating tools have been introduced as an alternative to robotic systems. The aim of this study was to compare perioperative outcomes between laparoscopic low anterior resection using ArtiSential® and robot-assisted surgery for rectal cancer.

METHODS

This retrospective study included 682 patients who underwent laparoscopic or robotic low anterior resection  for rectal cancer from September 2018 to December 2021. Among them, 82 underwent laparoscopic surgery using ArtiSential® (group A) and 201 underwent robotic surgery (group B). A total of 73 [group A; 66.37 ± 11.62; group B 65.79 ± 11.34] patients were selected for each group using a propensity score matching analysis.

RESULTS

There was no significant difference in the baseline characteristics between group A and B. Mean operative time was longer in group B than A (163.5 ± 61.9 vs 250.1 ± 77.6 min, p < 0.001). Mean length of hospital stay was not significantly different between the two groups (6.2 ± 4.7 vs 6.7 ± 6.1 days, p = 0.617). Postoperative complications, reoperation, and readmission within 30 days after surgery were similar between the two groups. Pathological findings revealed that the circumferential resection margins were above 10 mm in both groups (11.00 ± 7.47 vs 10.17 ± 6.25 mm, p = 0.960). At least 12 lymph nodes were sufficiently harvested, with no significant difference in the number harvested between the groups (20.5 ± 9.9 vs 19.7 ± 7.3, p = 0.753).

CONCLUSIONS

Laparoscopic low anterior resection using ArtiSential® can achieve acceptable clinical and oncologic outcomes. ArtiSential®, a multi-joint and articulating device, may serve a feasible alternative approach to robotic surgery in rectal cancer.

The Role of Postoperative Radiotherapy in T4 Rectal Cancer with Synchronous Distant Metastasis

PURPOSE/OBJECTIVE(S)

Studieson the role of surgery and local treatment in M1 rectal cancer have been actively studied recently. However, there is still controversy because no significant results have been reported for local control. The purpose of this study was to analyze the local control rates of postoperative radiotherapy for tumor stage T4 in M1 rectal cancer.

MATERIALS/METHODS

We investigated local recurrence after surgery for M1 rectal cancer that was operated at Seoul St. Mary's Hospital between 1995 and 2021. Locoregional recurrence rates were compared in patients who received postoperative pelvic radiotherapy and those who did not. In addition, an analytical comparison was performed only for patients with T4 rectal cancer. Statistical analysis was performed using the log rank test, and a p-value of less than 0.05 was considered significant.

RESULTS

During the investigation period, a total of 206 patients underwent surgery for M1 rectal cancer. There were 55 patients with T4 tumor stage. Of the 55 patients, 11 patients received radiotherapy after surgery, and 44 patients received systemic treatment such as chemotherapy after surgery without radiotherapy. During a median follow-up of 22 months, locoregional recurrence occurred in 1 (RT group) and 25 (no RT group) patients, respectively. Log-rank analysis of locoregional recurrence showed a significant difference between the two groups (p- value = 0.008). Death occurred in 10 (RT group) and 38 (no RT group) patients, respectively. The 2-year locoregional recurrence free-survival rates were 45.5% and 53.0%, respectively, and there was no significant difference between the two groups in the log-rank analysis.

CONCLUSION

Pelvic radiotherapy could be expected to improve locoregional recurrence in stage T4 of rectal cancer with synchronous distant metastasis. It would be warranted to prove this in a large-scale prospective study.

Rectal cancer lateral lymph nodes: multicentre study of the impact of obturator and internal iliac nodes on oncological outcomes

BACKGROUND

In patients with rectal cancer, enlarged lateral lymph nodes (LLNs) result in increased lateral local recurrence (LLR) and lower cancer-specific survival (CSS) rates, which can be improved with (chemo)radiotherapy ((C)RT) and LLN dissection (LLND). This study investigated whether different LLN locations affect oncological outcomes.

METHODS

Patients with low cT3-4 rectal cancer without synchronous distant metastases were included in this multicentre retrospective cohort study. All MRI was re-evaluated, with special attention to LLN involvement and response.

RESULTS

More advanced cT and cN category were associated with the occurrence of enlarged obturator nodes. Multivariable analyses showed that a node in the internal iliac compartment with a short-axis (SA) size of at least 7 mm on baseline MRI and over 4 mm after (C)RT was predictive of LLR, compared with a post-(C)RT SA of 4 mm or less (hazard ratio (HR) 5.74, 95 per cent c.i. 2.98 to 11.05 vs HR 1.40, 0.19 to 10.20; P < 0.001). Obturator LLNs with a SA larger than 6 mm after (C)RT were associated with a higher 5-year distant metastasis rate and lowered CSS in patients who did not undergo LLND. The survival difference was not present after LLND. Multivariable analyses found that only cT category (HR 2.22, 1.07 to 4.64; P = 0.033) and margin involvement (HR 2.95, 1.18 to 7.37; P = 0.021) independently predicted the development of metastatic disease.

CONCLUSION

Internal iliac LLN enlargement is associated with an increased LLR rate, whereas obturator nodes are associated with more advanced disease with increased distant metastasis and reduced CSS rates. LLND improves local control in persistent internal iliac nodes, and might have a role in controlling systemic spread in persistent obturator nodes.Members of the Lateral Node Study Consortium are co-authors of this study and are listed under the heading Collaborators.

Single-port versus conventional three-port laparoscopic totally extraperitoneal inguinal hernia repair: a randomized controlled trial

BACKGROUND

Single-port laparoscopic surgery (SPLS) has been introduced for totally extraperitoneal (TEP) inguinal hernia repair. Clinically, however, the benefits of single-port TEP (SP TEP) are unclear. This study aimed to compare short-term surgical outcomes between SP TEP and conventional laparoscopic TEP(CL TEP) inguinal hernia repair.

METHODS

Between January 2013 and February 2015, 99 men with primary unilateral inguinal hernia were randomized to the single-port or conventional 3-port TEP procedures. The primary end point was postoperative pain. Secondary end points were complications, postoperative hospital stay, days to return to daily normal activities, cosmesis, and quality of life (QOL).

RESULTS

We randomized 50 patients to SP TEP and 49 to CL TEP repair. The SP TEP group patients had significantly lower pain scores (visual analog scale) 7 days postoperation (p = 0.017). However, there were no significant differences between the two groups in postoperative pain scores 24 h (p = 0.44) and 4 weeks (p = 0.677) after operation and analgesic requirements on the operation day (p = 0.303) and 7 days after the operation (p = 0.204). Operation time, postoperative hospital stay, and complications were comparable between the two groups. The days to return to daily normal activities, QOL, and cosmetic satisfaction were not different between the two groups.

CONCLUSION

The outcomes of SP TEP hernia repair for operation time and morbidities were comparable to CL TEP, and postoperative pain was lower at 7 days than in CL TEP hernia repair. The SP TEP technique can be recommended as an alternative treatment for inguinal hernia repair in experienced hands.

Effects of Ambient Temperature on Growth Performance, Blood Metabolites, and Immune Cell Populations in Korean Cattle Steers

Exposure to cold may affect growth performance in accordance with the metabolic and immunological activities of animals. We evaluated whether ambient temperature affects growth performance, blood metabolites, and immune cell populations in Korean cattle. Eighteen Korean cattle steers with a mean age of 10 months and a mean weight of 277 kg were used. All steers were fed a growing stage-concentrate diet at a rate of 1.5% of body weight and Timothy hay ad libitum for 8 weeks. Experimental period 1 (P1) was for four weeks from March 7 to April 3 and period 2 (P2) was four weeks from April 4 to May 1. Mean (8.7°C) and minimum (1.0°C) indoor ambient temperatures during P1 were lower (p<0.001) than those (13.0°C and 6.2°C, respectively) during P2. Daily dry matter feed intake in both the concentrate diet and forage groups was higher (p<0.001) during P2 than P1. Average daily weight gain was higher (p<0.001) during P2 (1.38 kg/d) than P1 (1.13 kg/d). Feed efficiency during P2 was higher (p = 0.015) than P1. Blood was collected three times; on March 7, April 4, and May 2. Nonesterified fatty acids (NEFA) were higher on March 7 than April 4 and May 2. Blood cortisol, glucose, and triglyceride concentrations did not differ among months. Blood CD4+, CD8+, and CD4+CD25+ T cell percentages were higher, while CD8+CD25+ T cell percentage was lower, during the colder month of March than during May, suggesting that ambient temperature affects blood T cell populations. In conclusion, colder ambient temperature decreased growth and feed efficiency in Korean cattle steers. The higher circulating NEFA concentrations observed in March compared to April suggest that lipolysis may occur at colder ambient temperatures to generate heat and maintain body temperature, resulting in lower feed efficiency in March.

Association between prolonged breastfeeding and bone mineral density and osteoporosis in postmenopausal women: KNHANES 2010-2011

This study showed that a negative correlation between duration of breastfeeding and bone mineral density (BMD) in the lumbar spine and prolonged breastfeeding is an independent risk for osteoporosis in postmenopausal women. The present study suggests that postmenopausal women with a history of prolonged breastfeeding require more careful screening for osteoporosis.

INTRODUCTION

Several studies suggest that breastfeeding and childbirth lead to maternal calcium loss and a decline in BMD. While the association between breastfeeding and BMD immediately after weaning is well-established, the effects of breastfeeding on postmenopausal women have been controversial. The aim of this study was to examine the effects of breastfeeding on bone mineral density (BMD) and the prevalence of osteoporosis in postmenopausal women.

METHODS

The present study was a cross-sectional survey based on the Korea National Health and Nutrition Examination Survey (KNHANES) 2010 and 2011 data. The association between breastfeeding and BMD and osteoporosis was examined in 1222 postmenopausal women.

RESULTS

The duration of breastfeeding and BMD in the lumbar spine showed a negative correlation. The association between duration of breastfeeding and BMD remained significant after adjustment for reproductive factors and other confounding factors (P = 0.008). However, the number of deliveries and age at the time of delivery did not correlate with BMD at any site after adjustment. Moreover, the prevalence of osteoporosis in postmenopausal women with a history of prolonged breastfeeding was significantly higher than that in women with a short history of breastfeeding (≥37 months, OR = 3.292; 95 % CI 1.485-7.299). The prevalence of lumbar spine fracture showed a significant increasing trend with the increase in the duration of breastfeeding.

CONCLUSION

Prolonged breastfeeding was significantly associated with low BMD in the lumbar spine and higher prevalence of osteoporosis. However, the number of deliveries or age at the time of childbirth did not influence BMD.

The physiological roles of apolipoprotein J/clusterin in metabolic and cardiovascular diseases

Several isoforms of apolipoprotein J/clusterin (CLU) are encoded from a single gene located on chromosome 8 in humans. These isoforms are ubiquitously expressed in the tissues, and have been implicated in aging, neurodegenerative disorders, cancer progression, and metabolic/cardiovascular diseases including dyslipidemia, diabetes, atherosclerosis and myocardial infarction. The conventional secreted form of CLU (sCLU) is thought to be a component of high density lipoprotein-cholesterol. sCLU functions as a chaperone for misfolded proteins and it is thought to promote survival by reducing oxidative stress. Nuclear CLU, a truncated CLU formed by alternative splicing, is responsible for promoting apoptosis via a Bax-dependent pathway. There are putative regulatory sites in the promoter regions of CLU, which are occupied by transcription factors such as transforming growth factor (TGF)-β inhibitory element, activator protein-1, CLU-specific elements, and carbohydrate response element. However, the molecular mechanisms underlying the distinct roles of CLU in a variety of conditions remain unclear. Although the function of CLU in cancer or neurological disease has been studied intensively for three decades, physiological roles of CLU seem unexplored in the cardiovascular system and metabolic diseases. In this review, we will discuss general characteristics and regulations of CLU based on previous literature and assess the recent findings associated with its physiological roles in different tissues including the vasculature, heart, liver, kidney, adipose tissue, and brain.

MR traceable delivery of p53 tumor suppressor gene by PEI-functionalized superparamagnetic iron oxide nanoparticles

Cancer gene therapy involves the replacement of missing or altered genes with healthy ones. In this paper, we have proposed tumor suppressor gene-carrying superparamagnetic iron oxide nanoparticles (SPIONs) for anti-cancer gene therapy. Thermally crosslinked SPIONs (TCL-SPIONs) were conjugated with branched polyethylenimine (PEI 1800 Da) by EDC-NHS chemistry for p53 plasmid DNA delivery. The morphology of the bPEI conjugated TCL-SPIONs (bPEI-TCL-SPION) and pDNA-loaded bPEI-TCL-SPION nanoparticles was measured using transmission electron microscopy (TEM). The particle sizes of the pDNA-loaded bPEI-TCL-SPION nanoparticles were also confirmed by dynamic light scattering, and ranged from 100 to 130 nm, depending on the molar charge ratio. The fluorescently labeled pDNA was complexed with bPEI-TCL-SPION and its intracellular internalization was investigated using confocal microscopy. The p53 plasmid-loaded bPEI-TCL-SPION nanoparticles achieved significantly higher p53 tumor suppressor gene expression and cellular viability compared to positive controls. The expressed wild-type p53 protein suppressed tumor cell proliferation as compared to the mutant control. When transgene expression of the p53 tumor suppressor gene was evaluated at the mRNA level and quantified using real-time PCR, the results were highly dependent on the molar charge ratio (N/P) as well as the cancer cell type. SPIONs internalized within cancer cells were tracked by magnetic resonance (MR) imaging. It was concluded that bPEI-TCL-SPION could be used as efficient gene delivery carriers that can be tracked by MR imaging.

Association between interleukin-4R and TGF-β1 gene polymorphisms and the risk of colorectal cancer in a Korean population

AIM

Colorectal cancer is associated with inflammatory bowel disease. The mechanisms of how different genetic make-ups of cytokines might influence the individual susceptibility to develop particular types of tumours are still unknown. The authors analysed the association between genetic polymorphisms in cytokine/cytokine receptor genes and the risk of colorectal cancer in a Korean population.

METHOD

The authors assessed polymorphisms of the interleukin: IL-1, IL-1R, IL-2, IL-4, IL-4R, IL-10, transforming growth factor (TGF)-β1, IFN-γ genes in Korean patients with colorectal cancer (n = 170) and in a normal healthy control group (n = 130) to investigate the association between theses cytokine gene polymorphisms and the risk of colorectal cancer.

RESULTS

The IL-4R 1902*T allele was found to be associated with an increased risk of colon cancer (P < 0.01, OR = 2.0) and rectal cancer (P < 0.05, OR = 1.8). The IL-4R 1902*C allele was associated with a decreased risk of both colon cancer (P < 0.01, OR = 0.51) and rectal cancer (P < 0.05, OR = 0.5). The TFG-β1 10*T allele was found to be associated with an increased risk of colon cancer (P < 0.00, OR = 2.3) and the TFG-β1 10*C allele with a decreased risk of colon cancer (P < 0.00, OR = 0.43).

CONCLUSION

These results suggest that the genetic polymorphisms of IL-4R and TGF-β1 are associated with the risk of colorectal cancer in a Korean population.

A multicenter, randomized, placebo-controlled, double-blind phase II trial evaluating the optimal dose, efficacy and safety of LC 15-0444 in patients with type 2 diabetes

AIM

The objective of this study was to evaluate the optimal dose, efficacy and safety of a novel dipeptidyl peptidase-4 (DPP-IV) inhibitor, LC15-0444, in Korean subjects with type 2 diabetes mellitus treated by diet and exercise.

METHODS

This study was a double-blind, randomized, multicenter and parallel-group, dose-range finding study. We enrolled 145 patients (91 men and 54 women) with a median age of 53 years and a median body mass index of 25.1 kg/m(2) . The median baseline fasting plasma glucose (FPG) was 8.1 mmol/l, the median HbA1c was 7.9% and the median time since the diagnosis of diabetes was 3 years. After 2 weeks of an exercise/diet programme followed by 2 weeks of a placebo period, the subjects were randomized to one of the four following groups for a 12-week active treatment period: placebo and 50, 100 or 200 mg of LC15-0444.

RESULTS

All three doses of LC15-0444 significantly reduced the HbA1c from baseline compared to the placebo group (-0.06 vs. -0.98, -0.74 and -0.78% in the placebo and 50, 100 and 200 mg groups, respectively), without a significant difference between the doses. Subjects with a higher baseline HbA1c (≥8.5%) had a greater reduction in HbA1c. Insulin secretory function, as assessed using homeostasis model assessment-beta cell, C-peptide and the insulinogenic index, improved significantly with LC15-0444 treatment. Insulin sensitivity, as assessed using homeostasis model assessment-insulin resistance, also improved significantly after 12 weeks of treatment. The 50 and 200 mg groups had significantly reduced total cholesterol and low-density lipoprotein cholesterol levels at 12 weeks compared to the placebo group. No dosage of LC15-0444 affected weight or waist circumference. The incidences of adverse events were similar in all study subjects.

CONCLUSIONS

LC15-0444 monotherapy (50 mg for 12 weeks) improved the HbA1c, FPG level, oral glucose tolerance test results, β-cell function and insulin sensitivity measures, and was well tolerated in Korean subjects with type 2 diabetes.

A comparative study on the short-term clinicopathologic outcomes of laparoscopic surgery versus conventional open surgery for transverse colon cancer

BACKGROUND

The long-term oncologic stability of laparoscopic surgery for colon cancer was established, and laparoscopic surgery was accepted as an alternative to conventional open surgery for colon cancer. However, transverse colon cancer was excluded from the majority of the previous prospective studies. As a result, debate on laparoscopic surgery for transverse colon cancer continues. This study aimed to compare the clinicopathologic outcome of laparoscopic surgery with that of conventional open surgery for transverse colon cancer.

METHODS

From August 2004 to December 2007, 106 cases of transverse colon cancer were managed by resection at our institution, and 89 of these cases were included in this study. Age, sex, body mass index (BMI), operation time, blood loss, time to first flatus, time to start of diet, hospital stay, complications, tumor size, distal resection margin, proximal resection margin, and number of nodes harvested were compared between the two groups.

RESULTS

No significant differences were found between the laparoscopic and conventional groups in terms of age, sex, BMI, operation time, or hospital stay. The mean blood loss during the operations was significantly less in the laparoscopic group (113.8 +/- 128.9 ml) than in the conventional group (278.8 +/- 268.7 ml; p < 0.05). Moreover, the time to the first flatus was shorter (2.8 +/- 0.9 days vs. 4.4 +/- 2.0 days; p < 0.00) and the diet was started earlier (3.9 +/- 1.7 days vs. 5.4 +/- 1.9 days; p < 0.00) in the laparoscopic group. No intergroup differences in tumor size, proximal resection margin, or number of lymph nodes were observed. The mean distal resection margin was longer in the laparoscopic group (12.5 +/- 4.1 cm vs. 9.2 +/- 6.2 cm; p < 0.05).

CONCLUSION

Laparoscopic and conventional open surgeries were found to have similar clinical outcomes in transverse colon cancer, and the oncologic quality of laparoscopic surgery was found to be acceptable compared with conventional open surgery.

Surgical and pathological outcomes of laparoscopic surgery for transverse colon cancer

PURPOSE

Several multi-institutional prospective randomized trials have demonstrated short-term benefits using laparoscopy. Now the laparoscopic approach is accepted as an alternative to open surgery for colon cancer. However, in prior trials, the transverse colon was excluded. Therefore, it has not been determined whether laparoscopy can be used in the setting of transverse colon cancer. This study evaluated the peri-operative clinical outcomes and oncological quality by pathologic outcomes of laparoscopic surgery for transverse colon cancer.

MATERIALS AND METHODS

Analysis of the medical records of patients who underwent laparoscopic colorectal resection from August 2004 to November 2007 was made. Computed tomography, barium enema, and colonoscopy were performed to localize the tumor preoperatively. Extended right hemicolectomy, transverse colectomy, and extended left hemicolectomy were performed for transverse colon cancer. Surgical outcomes and pathologic outcomes were compared between transverse colon cancer (TCC) and other site colon cancer (OSCC).

RESULTS

Of the 312 colorectal cancer patients, 94 patients underwent laparoscopic surgery for OSCC, and 34 patients underwent laparoscopic surgery for TCC. Patients with TCC were similar to patients with OSCC in age, gender, body mass index, operating time, blood loss, time to pass flatus, start of diet, hospital stay, tumor size, distal resection margin, proximal resection margin, number of lymph nodes, and radial margin. One case in TCC and three cases in OSCC were converted to open surgery.

CONCLUSIONS

Laparoscopic surgery for transverse colon cancer and OSCC had similar peri-operative clinical and acceptable pathological outcomes.

Subthalamic lesion on MR imaging in a patient with nonketotic hyperglycemia-induced hemiballism

SUMMARY

Hemiballism with corresponding striatal T1 hyperintensity on MR imaging has occasionally been reported in patients with nonketotic hyperglycemia. However, the subthalamic nucleus lesion, which is believed to be pathogenetically related to hemiballism, is rarely documented in a living patient with nonketotic hyperglycemia. We describe a patient with nonketotic hyperglycemia-induced hemiballism, whose responsible lesion (ie, the subthalamus) was demonstrated by MR imaging.

Effect of AP-1 decoy using hemagglutinating virus of Japan-liposome on the intimal hyperplasia of the autogenous vein graft in mongrel dogs

Intimal hyperplasia is the leading cause of late vein graft failure. Smooth muscle cell proliferation and migration is the underlying mechanism. Pharmacological approaches to prolong vein graft patency have produced limited results. AP-1 proteins play a role in the expression of many genes involved in cellular proliferation and cell cycle progression. Previously we reported inhibition of vascular smooth muscle cell migration, proliferation, and intimal hyperplasia in the balloon-injured rat carotid artery using an AP-1 decoy with HVJ-liposomes. In this report, we evaluated the effect of the AP-1 decoy on intimal hyperplasia in a large animal model. The jugular vein was transfected with hemagglutinating virus of Japan-liposomes containing the AP-1 decoy or scrambled oligonucleotides. An interposition graft was performed with the pretreated jugular vein between the transected femoral arteries. The graft was harvested at 16 weeks after the procedure. The intimal area was compared: the intimal area of the AP-1 decoy-treated versus control group was 47.3 +/- 15.2 versus 102.3 +/- 15.9 (P < .05), respectively. In conclusion, AP-1 decoy using HVJ-liposomes effectively prevented intimal hyperplasia of an autogenous vein graft in mongrel dogs.

E2F decoy oligodeoxynucleotides on neointimal hyperplasia in canine vein graft

Double-stranded DNA with high affinity to E2F as a decoy cis-element blocks the activation of genes mediating the cell cycle, resulting in effective suppression of the smooth muscle cell proliferation that causes intimal hyperplasia. To evaluate the effect of the E2F decoy to suppress neointimal hyperplasia autogenous venous bypass grafts were performed in dogs after incubation with heparin (group 1), with E2F decoy oligodeoxynucleotides (ODN) (groups 2 and 3), or with a random ODN (group 4) using a Japan-liposomeal method based on a hemagglutinating virus. The intimal and medial cross-sectional surface area of the anastomotic site was measured at 4 months after bypass surgery in groups 1, 3, and 4 by computerized planimetry and at 4 weeks in group 2 to compare the intimal/medial (I/M) area ratios. Autogenous vein grafts treated with E2F decoy showed a significant reduction in I/M area ratio (0.26 +/- 0.11) compared with the heparin-treated control group (1.49 +/- 0.29) or the mismatched ODN-treated group (1.61 +/- 0.28; P = .000). There was no difference in the I/M area ratio according to experimental periods (groups 2 vs 3: 0.26 +/- 0.11 vs 0.37 +/- 0.32; P = .446) or the anastomotic sites (proximal vs distal; P = .934). In conclusion, an E2F decoy can suppress neointimal hyperplasia in autogenous vein grafts, which may prolong patency by reducing graft stenosis.

Transcription factor decoy for AP-1 reduces mesangial cell proliferation and extracellular matrix production in vitro and in vivo

Diabetic nephropathy is characterized by an expansion of glomerular mesangium, caused by mesangial cell proliferation and excessive accumulation of extracellular matrix (ECM) proteins, which eventually leads to glomerulosclerosis and renal failure. Activator protein-1 (AP-1), a transcription factor, is implicated in the transcriptional regulation of a wide range of genes participating in cell proliferation and ECM production. This investigation was undertaken to test the hypothesis that AP-1 plays an important role in ECM gene expression, and to develop a molecular therapeutic strategy based on decoy oligodeoxynucleotides (ODN). In this report, we show that transfection with AP-1 decoy ODN strongly inhibits high glucose- and angiotensin II-induced cell proliferation and expression of ECM genes in cultured mesangial cells in vitro. Administration of AP-1 decoy ODN into streptozotocin-induced diabetic rat kidney in vivo using the hemagglutinating virus of Japan (HVJ)-liposome method virtually abolished TGF-beta1 and plasminogen activator inhibitor-1 expression. Our results collectively indicate that AP-1 activation is crucial for mesangial cell proliferation and ECM production in response to high glucose and angiotensin II. Moreover, use of stable AP-1 decoy ODN combined with the highly effective HVJ-liposome method provides a novel potential molecular therapeutic strategy for the prevention of diabetic nephropathy.

Advantages of the circular dumbbell decoy in gene therapy and studies of gene regulation

Decoy oligodeoxynucleotides (ODN) that can reduce the trans-activity of transcription factors may be highly useful in gene therapy and the study of transcriptional regulation. Several different types of these double-stranded DNA decoys have been developed, including unmodified oligonucleotide duplexes, alphabeta-anomeric oligonucleotides, and oligonucleotide duplexes with methylphosphonate- and phosphorothioate-modified linkages. The latter ODNs have been particularly extensively studied but suffer from a number of limitations, including their insensitivity to polymerases, their lack of sequence specificity, and their tendency to activate immune responses. To resolve these problems, circular dumbbell (CD) double-stranded ODNs were developed. These CD ODNs are constructed by the circularization of the 3' and 5' ends of the oligonucleotides and enzymatic ligation. They exhibit high resistance to nucleases, are easily taken up by cells, and have a nontoxic unmodified backbone that resembles natural DNA. In this article, we review the method of constructing CD ODNs and their advantages compared to other modified ODNs for use as transcription decoys.

Effect of estrogen on endothelial dysfunction in postmenopausal women with diabetes

BACKGROUND

Treatment with estrogen causes increased release of nitric oxide and this appears to be an important mechanism involved in the cardioprotective effect of estrogen. Previous studies have clearly shown that estrogen has an acute vasodilatory effect. Recently, abnormality of flow mediated endothelial dilation, which is defined as an endothelial dysfunction, has been proposed as an early manifestation of atherogenesis. However, its effect in type 2 diabetes is unknown. Stimulus-provoked endothelium dependent dilatation, using high-resolution external vascular ultrasound, is a useful method in the measurement of endothelial function. The main advantages of this method are that it is completely non-invasive, accurate and reproducible. This classical method for the measurement of endothelial dysfunction, utilizing non-invasive, high-resolution ultrasonography, has some limitations especially in terms of reproducibility. To improve the accuracy and reproducibility of this method, measurements made for this study involved the use of an additional attachment. This device was an ultrasound probe that was attached to the arm of patient. In addition, this study evaluated not only a change in diameter in terms of flow mediated vasodilation, but also initial and peak response times during this test. The aims of this study are: (1) to evaluate the flow mediated peak vasoreactivity (FMD), the lag time from base line to initiation of vasodilation (IRT) and the peak response of endothelial dependent vasodilation in a control group and in young diabetic patients; and (2) to evaluate the effect of estrogen treatment on flow mediated vasodilation in postmenopausal women with diabetes.

METHOD

Measurements were taken for flow mediated vasodilation (endothelial dependent vasodilation: FMD), endothelial independent vasodilation (EID) and lag time from base line to initial reaction of FMD. The aforementioned non-invasive method and attachment were used. Subjects for the experiment were 12 young people with diabetes (six male and six female, mean age 26.3) and 12 age-matched healthy controls (six male and six female, mean age 25.6). In addition, measurements were taken for FMD, EID and lag time in the brachial artery before and after estrogen supplementation (Premarin 0.625 mg for 7 days). Subjects for the experiment were 16 normal postmenopausal women and 18 age-matched postmenopausal women with type 2 diabetes.

RESULT

There is no significant difference in BMI (body mass index), mean age, or blood pressure between the control group and the young diabetic group. There were no differences in age, total and LDL cholesterol levels or body mass index between the groups of postmenopausal women (P<0.05). However, the HDL cholesterol level was found to be significantly lower in postmenopausal women with diabetes than in normal postmenopausal women (respectively, a mean+/-SD; 38.95+/-11.96 mg/dl vs. 52.20+/-9.55 mg/dl, P<0.05). The FMD of young diabetic patients is slightly lower than that of age-matched young healthy controls (healthy control: 8.9+/-2.7%, young diabetic patients: 6.3+/-2.1%, P<0.05). There was no difference in endothelial independent vasodilation between the control group and the young diabetic group. The IRT of FMD was significantly shorter in the healthy control group than in the young diabetic group (healthy control: 20.4+/-2.8 s, diabetic group: 29.5+/-5.4 s, P<0.0001). In contrast, the IRT of EID was no different between the two groups. The IRT of FMD showed a significant negative correlation with FMD (r=-0.61, P<0.01) and a significant negative correlation with high-density lipoprotein (HDL) cholesterol (r=-0.68, P<0.0001). The basal endothelium dependent vascular reactivity was significantly decreased in postmenopausal women with diabetes compared with normal postmenopausal women (8.0+/-3.9 vs. 13.7+/-6.2%, P<0.05). Estrogen supplementation increased endothelium dependent vasodilation not only in postmenopausal women with diabetes (from 8.0+/-3.9 to 15.1+/-4.0%, P<0.05) but also in normal postmenopausal women (from 13.7+/-6.2 to 20.1+/-4.7%, P<0.05). In contrast, the responses to sublingual nitroglycerin were comparable between postmenopausal women with diabetes (from 21.1+/-6.0 to 22.1+/-4.1%, P>0.05) and normal postmenopausal women (from 25.8+/-7.8 to 25.2+/-4.5%, P>0.05), both before and after estrogen supplementation.

CONCLUSION

These findings indicate that in addition to the percentage change in FMD, lag time from base line to initial response time (IRT) of FMD is a good indicator for evaluation of endothelial dysfunction. Also, this new parameter may be a more sensitive parameter for differentiation between the diseased state and the normal state of the endothelium than percentage changes in FMD. In terms of postmenopausal women, endothelial dysfunction was prominent in women with diabetes and was significantly improved by estrogen but not reversed. These results suggest that other factors in addition to estrogen deficiency play a role in endothelial dysfunction in postmenopausal women with diabetes mellitus.

The effect of parental imprinting on the INS-IGF2 locus of Korean type I diabetic patients

BACKGROUND

Insulin-dependent diabetes mellitus (IDDM) is caused by the autoimmune destruction of pancreatic beta-cells. Susceptibility to IDDM appears to depend on more than one genetic locus. Evidence of a genetic linkage for IDDM2 was found in male meioses from French and North American populations. It is linked to maternal imprinting (i.e. monoalleleic expression of the insulin gene) that is considered the most likely cause of these gender-related differences. IGF2 is expressed only in the paternal allele and, therefore, is considered a candidate gene for IDDM2 transmission because of its important autocrine/paracrine effects on the thymus, lymphocytes and pancreas. Nevertheless, it remains controversial whether the parental origin of IDDM2 influences IDDM susceptibility.

METHODS

Using PCR and semi-quantitative RT-PCR, we analyzed the INS/Pstl + 1127 and IGF2/Apal polymorphisms and RNA expression level between Pstl (+/-) and Pstl (+/+) to determine genotype and allele-specific expression of the INS and IGF2 genes.

RESULTS

INS/Pstl (+/+) and IGF2/Apal (+/-) were observed in 36 (97.3%) of 37 IDDM patients and in 29 (72.5%) of 40 IDDM patients, respectively. The presence of both IGF2 alleles in RNA was observed in 21 (91.6%) of 24 IDDM patients. Our results show a 3-fold increase in RNA expression from Pstl (+/-) allele over Pstl (+/+) allele.

CONCLUSION

Our conclusion does not entirely exclude IGF2 as the gene involved in IDDM2, even though the parental effect of IDDM2 transmission is not related to IGF2 maternal imprinting. The INS genotype appeared mostly in the Pstl (+/+) homozygote and, therefore, we could not explain the INS imprinting pattern in Korean type 1 diabetic patients. Genetic differences between populations may account for the discrepancy between Korean type I diabetic patients and American or French type I diabetic patients.

Effects of exogenous recombinant interleukin-12 on immune responses and protection against Brucella abortus in a murine model

This study determined if murine interleukin-12 (IL-12) would influence immunity in mice vaccinated with live or killed Brucella abortus strain RB51 (SRB51). Mice received live or gamma-irradiated SRB51 bacteria alone, or with IL-12 (0.5 or 1.0 microg, 2x or 3x), whereas other mice received saline or IL-12 alone. Post-vaccination antibody responses to live or killed SRB51 and clearance of live SRB51 from splenic tissue were not influenced by IL-12 treatments. Mice were challenged at 12 weeks with 4 x 10(4) cfu of B. abortus strain 2308 (S2308) and were euthanized 2 weeks later. The highest IL-12 treatment increased (P < 0.05) post-challenge antibody responses when co-administered with killed SRB51. Co-administration of 1.0 microg of IL-12 with live SRB51, but not killed SRB51, reduced (P < 0.05) S2308 colonization of splenic tissues. Our data suggest that although IL-12 may augment protective immunity induced by live SRB51, it does not influence protection induced by vaccination with killed SRB51.

Coumarins with monoamine oxidase inhibitory activity and antioxidative coumarino-lignans from Hibiscus syriacus

A previously undescribed coumarin and a new coumarino-lignan, together with the known compounds scopoletin and cleomiscosins A, C, and D, have been isolated from the root bark of Hibiscus syriacus, and their structures were assigned on the basis of various spectral studies. The coumarin analogue and scopoletin inhibited monoamine oxidase with moderate IC(50) values. The new coumarino-lignan and cleomiscosin C showed lipid peroxidation inhibitory activity comparable to vitamin E.

Ellagic acid rhamnosides from the stem bark of Eucalyptus globulus

Four ellagic acid rhamnosides were isolated from the stem bark of Eucalyptus globulus. Their structures have been established on the basis of the analysis of their 1H NMR, 13C NMR, HMBC, IR and MS spectral data. The HMBC data of these compounds were most useful for their structure determinations, with these bring determined to be 3-O-methylellagic acid 3'-O-alpha-rhamnopyranoside, 3-O-methylellagic acid 3'-O-alpha-3''-O-acetylrhamnopyranoside, 3-O-methylellagic acid 3'-O-alpha-2''-O-acetylrhamnopyranoside, 3-O-methylellagic acid 3'-O-alpha-4''-O-acetylrhamnopyranoside, respectively. Their antioxidant activities were evaluated by measuring the inhibition of lipid peroxidation using rat liver microsomes, with IC50 values of 10.0-14.0 microg/ml.

Transcription factor decoy for activator protein-1 (AP-1) inhibits high glucose- and angiotensin II-induced type 1 plasminogen activator inhibitor (PAI-1) gene expression in cultured human vascular smooth muscle cells

AIMS/HYPOTHESIS

Multiple factors, including hyperglycaemia and angiotensin II (Ang II), stimulate plasminogen activator inhibitor-1 (PAI-1) gene expression in human vascular smooth muscle cells. This study tested the hypothesis that hyperglycaemia and Ang II stimulate PAI-1 gene expression through activator protein-1 (AP-1) binding sites.

METHODS

We evaluated the role of AP-1 in PAI-1 gene expression in human vascular smooth muscle cells under high D-glucose and Ang II stimulation using a double-stranded cis-element AP-1 oligodeoxynucleotide (decoy ODN).

RESULTS

Activator protein 1 activity was stimulated by high glucose and Ang II treatment and the AP-1 decoy ODN, but not a mismatched decoy ODN, competed for AP-1 activity. The increase in PAI-1 expression by high glucose and Ang II was significantly attenuated by the AP-1 decoy ODN (p <0.05 or p < 0.01). The increase in PAI-1 expression by high glucose and Ang II action on AP-1 sites was also confirmed by promoter analysis of PAI-1. Activator protein 1 activation in response to either high glucose or co-stimulation with high glucose and Ang II was inhibited completely by calphostin C (a PKC inhibitor) and partially by genistein (a protein tyrosine kinase inhibitor).

CONCLUSION/INTERPRETATION

This study shows that high glucose and Ang II stimulate PAI-1 expression through AP-1 binding sites. Signal transduction after AP-1 activation by both high glucose and Ang II largely depends on PKC activation. These data indicate an important role for AP-1 in PAI-1 expression.

Different uptake of 99mTc-ECD adn 99mTc-HMPAO in the same brains: analysis by statistical parametric mapping

The purpose of this study was to investigate the differences between technetium-99m ethyl cysteinate dimer (99mTc-ECD) and technetium-99m hexamethylpropylene amine oxime (99mTc-HMPAO) uptake in the same brains by means of statistical parametric mapping (SPM) analysis. We examined 20 patients (9 male, 11 female, mean age 62+/-12 years) using 99mTc-ECD and 99mTc-HMPAO single-photon emission tomography (SPET) and magnetic resonance imaging (MRI) of the brain less than 7 days after onset of stroke. MRI showed no cortical infarctions. Infarctions in the pons (6 patients) and medulla (1), ischaemic periventricular white matter lesions (13) and lacunar infarction (7) were found on MRI. Split-dose and sequential SPET techniques were used for 99mTc-ECD and 99mTc-HMPAO brain SPET, without repositioning of the patient. All of the SPET images were spatially transformed to standard space, smoothed and globally normalized. The differences between the 99mTc-ECD and 99mTc-HMPAO SPET images were statistically analysed using statistical parametric mapping (SPM) 96 software. The difference between two groups was considered significant at a threshold of uncorrected P values less than 0.01. Visual analysis showed no hypoperfused areas on either 99mTc-ECD or 99mTc-HMPAO SPET images. SPM analysis revealed significantly different uptake of 99mTc-ECD and 99mTc-HMPAO in the same brains. On the 99mTc-ECD SPET images, relatively higher uptake was observed in the frontal, parietal and occipital lobes, in the left superior temporal lobe and in the superior region of the cerebellum. On the 99mTc-HMPAO SPET images, relatively higher uptake was observed in the medial temporal lobes, thalami, periventricular white matter and brain stem. These differences in uptake of the two tracers in the same brains on SPM analysis suggest that interpretation of cerebral perfusion is possible using SPET with 99mTc-ECD and 99mTc-HMPAO.

Lipid peroxidation inhibitory activity of some constituents isolated from the stem bark of Eucalyptus globulus

Twelve compounds with lipid peroxidation inhibitory activity were isolated from the stem bark of E. globulus. Their structures were assigned as a new aromatic monoterpene (1) and eleven known compounds, pinoresinol (2), vomifoliol (3), 3,4,5-trimethoxyphenol 1-O-beta-D-(6'-O-galloyl)glucopyranoside (4), methyl gallate (5), rhamnazin (6), rhamnetin (7), eriodictyol (8), quercetin (9), taxifolin (10), engelitin (11), and catechin (12) on the basis of UV, mass, and NMR spectroscopic analyses. These compounds except vomifoliol significantly inhibited lipid peroxidation in rat liver microsome.

Curtisians A-D, new free radical scavengers from the mushroom Paxillus curtisii

In our continuous investigation for free radical scavengers from extracts of fruit body of basidiomycetes, we have isolated four new p-terphenyl compounds, designated as curtisians A-D, from the methanolic extract of the fruit body of Paxillus curtisii. These compounds were isolated by silica gel and Sephadex LH-20 column chromatographies, preparative-TLC and HPLC, consecutively. The structures of curtisians were assigned as p-terphenyls with substituents of acetyl, benzoyl, phenylbutyryl, 3-hydroxybutyryl and 3-acetoxybutyryl. Curtisians A, B, C and D exhibited inhibitory activity against lipid peroxidation with IC50, values of 0.15, 0.17, 0.24 and 0.14 microg/ml, respectively.

The adjuvant effect of a single dose of interleukin-12 on murine immune responses to live or killed Brucella abortus strain RB51

This study was designed to determine if a single 0.5 microg administration of recombinant murine interleukin-12 (IL-12) would influence immune responses of mice vaccinated with live or killed Brucella abortus strain RB51 (SRB51). Mice were vaccinated intraperitoneally with 5 x 10(8) cfu of live or gamma-irradiated SRB51 bacteria alone, or in combination with 0.5 microg of IL-12. Control mice received saline or 0.5 microg of IL-12. Serologic responses and spleen weights after vaccination were greater in mice vaccinated with live SRB51 when compared to mice receiving killed SRB51 or control treatments. Administration of a single dose of IL-12 as a vaccine adjuvant did not influence immune responses, clearance of live SRB51, or resistance against B. abortus strain 2308 (S2308) challenge. The results of this study suggest that a single administration of 0.5 microg of IL-12 at the time of vaccination does not have significant adjuvant effects on vaccine-induced immune responses against live or killed Brucella.

An antioxidant lignan and other constituents from the root bark of Hibiscus syriacus

A new lignan named as hibiscuside, (+)-pinoresinol 4-O-[beta-glucopyranosyl (1--->2)-alpha-rhamnoside] (1), and a known lignan, syringaresinol (2) were isolated from the root bark of Hibiscus syriacus together with two feruloyltyramines (3,4) and three known isoflavonoids (5,6,7). The structures of these compounds have been established on the basis of their NMR, mass UV spectra. Among these phenolic compounds, 6"-O-acetyldaidzin (5), 6"-O-acetylgenistin (6), and 3-hydroxydaidzein (7) with IC(50) values of 8.2, 10.6, and 4.1 microM, respectively, significantly inhibited lipid peroxidation in rat liver microsomes. Hibiscuside (1), E- and Z-N-feruloyl tyramines (3,4) exhibited moderate antioxidant activity.

d-Alpha-tocopherol prevents the hyperglycemia induced activation of diacylglycerol (DAG)-protein kinase C (PKC) pathway in vascular smooth muscle cell by an increase of DAG kinase activity

We have reported that d-alpha-tocopherol can prevent hyperglycemia-induced activation of DAG and PKC levels in vascular tissues as well as normalizing retinal blood flow and renal hyperfiltration. The mechanism of this effect, however, is not clear. Aside from alpha-tocopherol's principal role as an antioxidant agent, it has also been shown to act as a membrane stabilizer. Another possibility is that the effect of alpha-tocopherol is focused on the activation of DAG kinase, which is a key enzyme in the metabolism of DAG. Therefore, in this study, we examined the effect of alpha-tocopherol on the DAG kinase activity in vascular smooth muscle cell. We have also examined the effect of alpha-tocopherol, its analogues, and probucol on DAG kinase activities and expression. The present study showed that d-alpha-tocopherol's inhibitory effect on DAG-PKC pathway is by increasing DAG kinase activity in rat and human vascular smooth muscle cell (VSMC). Total DAG level was increased by 40 +/- 10% (mean +/- S.E.) (P < 0.05) in human VSMC, after exposure to 22 vs 5 mM glucose. This increase was normalized by d-alpha-tocopherol treatment in a concentration-dependent manner. In parallel, DAG kinase activation by d-alpha-tocopherol was also induced in a time- and dose-dependent manner. DAG kinase activity was increased by 57 +/- 19% (P < 0.05) in human VSMC and 112 +/- 35% (P < 0.05) in rat VSMC after 24 h of incubation with d-alpha-tocopherol (100 microg/ml). Another lipophilic antioxidant, probucol, also increased DAG kinase activity by 124 +/- 34%, but other vitamin E analogues with much less antioxidant potencies were ineffective. Western blots of various DAG kinase isoforms were not changed by d-alpha-tocopherol treatment. These results provide strong and detailed evidence that d-alpha-tocopherol can prevent hyperglycemia induced DAG-PKC activation by enhancing DAG kinase activity, probably through an antioxidant effect.

Two bioactive pentacyclic triterpene esters from the root bark of Hibiscus syriacus

Two new triterpene caffeates have been isolated from the root bark of Hibiscus syriacus. Their structures were established through various spectral studies as 3beta,23,28-trihydroxy-12-oleanene 23-caffeate (1) and 3beta,23,28-trihydroxy-12-oleanene 3beta-caffeate (2). Compounds 1 and 2 showed lipid peroxidation inhibitory activity and significant cytotoxicity against a panel of human cancer cell lines.

Synthesis and cytotoxic activities of 6-chloro-7-arylamino-5,8-isoquinolinediones

6-Chloro-7-arylamino-5,8-isoquinolinediones were newly synthesized and evaluated for in vitro cytotoxic activities against five human solid tumor cell lines. Among them, 5b, 5c and 5d exhibited potent activities against the cell lines HCT-15 and SK-MEL-2.

Synthesis and antibacterial activity of 1 beta-methylcarbapenem having a 1,3-diazabicyclo[3.3.0]octan-4-one moiety, Part II

The synthesis of a new series of 1 beta-methylcarbapenems having a 1,3-diazabicyclo[3.3.0]octan-4-one moiety is described. Their in vitro antibacterial activities against both Gram-positive and Gram-negative bacteria are tested and the effect of substituent on the bicyclic ring was investigated. A particular compound (11 h) having aminoethyl group showed the most potent antibacterial activity.

Adjacent proline residues in the inhibitory domain of the Oct-2 transcription factor play distinct functional roles

A 40 amino acid region of Oct-2 from amino acids 142 to 181 functions as an active repressor domain capable of inhibiting both basal activity and activation of promoters containing a TATA box, but not of those that contain an initiator element. Based on our observation that the equivalent region of the closely related Oct-1 factor does not act as an inhibitory domain, we have mutated specific residues in the Oct-2 domain in an attempt to probe their importance in repressor domain function. Although mutations of several residues have no or minimal effect, mutation of proline 175 to arginine abolishes the ability to inhibit both basal and activated transcription. In contrast, mutation of proline 174 to arginine confers upon the domain the ability to repress activation of an initiator-containing promoter by acidic activation domains, and also suppresses the effect of the proline 175 mutation. Hence, adjacent proline residues play key roles in the functioning of the inhibitory domain and in limiting its specificity to TATA-box-containing promoters.

Three naphthalenes from root bark of Hibiscus syriacus

Three new naphthalenes, designated as syriacusins A-C, were isolated from the root bark of Hibiscus syriacus. These compounds were identified as 2,7-dihydroxy-6-methyl-8-methoxy-1-naphthalenecarbaldehyde, 2-hydroxy-6-hydroxymethyl-7,8-dimethoxy-1-naphthalenecarbaldehyde, 1-carboxy-2,8-dihydroxy-6-methyl-7-methoxynaphthalenecarbolactone (1-->8), respectively, on the basis of various spectral studies. The compounds inhibited lipid peroxidation with IC50s of 0.54, 5.90 and 1.02 micrograms ml-1, respectively. The first compound also showed cytotoxicity against some human cancer cell lines with an ED50 of 1.5-2.4 micrograms ml-1.

Decursinol angelate: a cytotoxic and protein kinase C activating agent from the root of Angelica gigas

A cytotoxic compound was purified from the root of Angelica gigas Nakai by normal phase HPLC. As a result of the structure analysis by mass, IR, 1H-NMR, and 13C-NMR spectrometry, the compound was identified as decursinol angelate, a structural isomer of decursin, and characterized originally from Sesei grandivittatum. Decursinol angelate showed in vitro cytotoxicity and protein kinase C activating activities like decursin.

New indole derivatives with free radical scavenging activity from Agrocybe cylindracea

Two new indole derivatives were isolated as free radical scavengers from the MeOH extract of Agrocybe cylindracea. The structures of these compounds were determined to be 6-hydroxy-1H-indole-3-carboxaldehyde (1) and 6-hydroxy-1H-indole-3-acetamide (2) on the basis of spectroscopic studies. Compounds 1 and 2 inhibited lipid peroxidation in rat liver microsomes, with IC50 values of 4.1 and 3.9 micrograms/mL, respectively.

Prevention of glomerular dysfunction in diabetic rats by treatment with d-alpha-tocopherol

Because d-alpha-tocopherol (vitamin E) has been shown to decrease diacylglycerol (DAG) levels and prevent the activation of protein kinase C (PKC), which is associated with retinal and renal dysfunctions in diabetes, the study presented here characterized the effect of d-alpha-tocopherol treatment to prevent glomerular hyperfiltration and increased albuminuria as well as PKC activities in streptozotocin (STZ)-induced diabetic rats. Two weeks after the induction of diabetes, total DAG content and PKC activity in glomeruli were significantly increased in diabetic rats by 106.4 +/- 16.8% and 66.4 +/- 8.4%, respectively, compared with control rats. Intraperitoneal injection of d-alpha-tocopherol (40 mg/kg of body weight) every other day prevented the increases in total DAG content and PKC activity in glomeruli of diabetic rats. Glomerular filtration rate (GFR) and filtration fraction (FF) were significantly elevated to 4.98 +/- 0.34 mL/min and 0.36 +/- 0.05, respectively, in diabetic rats, compared with 2.90 +/- 0.14 mL/min and 0.25 +/- 0.02, respectively, in control rats. These hemodynamic abnormalities in diabetic rats were normalized to 2.98 +/- 0.09 mL/min and 0.24 +/- 0.01, respectively, by d-alpha-tocopherol. Albuminuria in 10-wk diabetic rats was significantly increased to 9.1 +/- 2.2 mg/day compared with 1.2 +/- 0.3 mg/day in control rats, whereas d-alpha-tocopherol treatment improved albumin excretion rate to 2.4 +/- 0.6 mg/day in diabetic rats. To clarify the mechanism of d-alpha-tocopherol's effect on DAG-PKC pathway, the activity and protein levels of DAG kinase alpha and gamma, which metabolize DAG to phosphatidic acid, were examined. Treatment with d-alpha-tocopherol increased DAG kinase activity in the glomeruli of both control and diabetic rats, by 22.6 +/- 3.6% and 28.5 +/- 2.3% respectively, although no differences were observed in the basal DAG kinase activity between control and diabetic rats. Because immunoblotting studies did not exhibit any difference in the protein levels of DAG kinase alpha and gamma, the effect of d-alpha-tocopherol is probably modulating the enzyme kinetics of DAG kinase. These findings suggest that the increases in DAG-PKC pathway play an important role for the development of glomerular hyperfiltration and increased albuminuria in diabetes and that d-alpha-tocopherol treatment could be preventing early changes of diabetic renal dysfunctions by normalizing the increases in DAG and PKC levels in glomerular cells.

Betulinans A and B, two benzoquinone compounds from Lenzites betulina

Two lipid peroxidation inhibitors, designated as betulinans A (1) and B (2), were isolated from the MeOH extract of Lenzites betulina. The structures of these compounds have been determined to be 2,5-diphenyl-3,6-dimethoxy-p-benzoquinone and 2-phenyl-3-methoxy-[1H-2-benzopyran][4,3-e][p]benzoquinone, respectively, on the basis of various spectral data. Betulinans A and B inhibited lipid peroxidation with IC50 values of 0.46 and 2.88 micrograms/mL, respectively.

Cytotoxic benzyl dihydroflavonols from Cudrania tricuspidata

Three new dihydroflavonols, gericudranins A-C were isolated from the stem bark of Cudrania tricuspidata. They were identified as 6,8-di-p-hydroxybenzyltaxifolin, 8-p-hydroxybenzyltaxifolin and 6-p-hydroxybenzyltaxifolin, respectively, by means of spectral studies. These compounds were cytotoxic to human tumor cell lines, such as CRL 1579 (skin), LOX-IMVI (skin), MOLT-4F (leukemia), KM12 (colon) and UO-31 (renal) in culture, with ED50 values of 2.7-31.3 micrograms ml-1.

Metastatic pleural cancer in radionuclide angiocardiography. A pulmonary time-activity curve mimicking left-to-right cardiac shunt

A 55-year-old man, with a history of nephrectomy for renal cell carcinoma, was evaluated using radionuclide angiocardiography to exclude cardiac shunts as the cause of vascular bruits heard at auscultation. A pulmonary time-activity curve derived from the right lung showed a pattern typical of a large left-to-right shunt, whereas that from the left lung was normal. Increased systemic arterial flow to the lateral right chest was noted in early dynamic images. Subsequent studies revealed that this flow and the abnormal time-activity curve of the right lung were due to systemic arterial supply to metastatic pleural cancer, originating from the kidney. The authors conclude that special caution should be undertaken in the interpretation of the radionuclide angiocardiography for determining left-to-right cardiac shunts, especially in those showing a asymmetric pulmonary time-activity curve.

Evaluation of factors affecting the accuracy of impressions using quantitative surface analysis

Impression material goes from a plastic to an elastic state during setting. Movement of the impression and excessive seating pressure during this transition can cause distortion in the impressions. The purpose of this study is to determine if the impression distortion is related to movement during setting or to distortion of the putty phase in the two-step impressioning technique. A master model of a maxillary quadrant of teeth was impressed using four different procedures: 1) one-step technique without movement (1S-NM); 2) one-step technique with movement (1S-M); 3) two-step technique without movement (2S-NM); and 4) two-step technique with movement (2S-M). An artificial oral environment and surface analysis technique of the Minnesota Dental Research Center for Biomaterials and Biomechanics were used to produce the impressions and measure their accuracy. A digitized image of the first premolar of the master model was aligned with a digitized image of the first premolar of each epoxy model using AnSur. The root mean squared difference (RMS) between the aligned images is a measure of the distortion. The corresponding RMS values for the different methods were: 1S-NM = 23.7 +/- 9.21; 1S-M = 20.4 +/- 3.9; 2S-NM = 20.5 +/- 7.7; 2S-M = 21.3 +/- 4.4. Statistical analysis using a two-way analysis of variance showed no difference at the 0.05 level of significance. Pairwise comparison using the Tukey method showed that neither technique (one-step vs two-step) nor movement is a significant factor. These results showed that low seating pressure will not cause any greater distortions in the two-step impression technique than in the one-step technique, and minor movement during the setting of the impression material will no cause distortion.

Plasma type IV collagen and fibronectin concentrations in diabetic patients with microangiopathy

In diabetes mellitus, thickening of basement membrane in capillaries and small vessels is a well-known finding and important in the progression of diabetic microangiopathy. We evaluated whether the plasma levels of type IV collagen and fibronectin, which are important factors of basement membrane, are related with the presence of diabetic microangiopathy. Plasma type IV collagen and fibronectin levels were measured in 40 healthy controls (Mean +/- SD, age; 50.3 +/- 5.5 yr) and 94 diabetic patients (age; 52.4 +/- 13.5 yr) with and without microvascular complications. The mean plasma levels of type IV collagen (5.3 +/- 2.9 ng/ml) and fibronectin (474.4 +/- 119.4 ug/ml) in diabetic patients were significantly higher (p < 0.01) than in healthy controls (3.7 +/- 1.3 ng/ml and 319 +/- 50.9 ug/ml). The mean plasma level of type IV collagen in diabetic patients with complications (6.6 +/- 3.7 ng/ml) was significantly higher (p < 0.01) than in those without complications (4.3 +/- 1.7 ng/ml) and became higher in more complicated patients. Furthermore, the severity of retinopathy and several indicators of nephropathy such as serum BUN, creatinine and proteinuria were closely associated with plasma type IV collagen level and a significant correlation was found between plasma type IV collagen and creatinine clearance (r = -0.31, p < 0.001). There was no significant difference in plasma fibronectin concentrations, however, between the diabetic patients with complications and those without complications.(ABSTRACT TRUNCATED AT 250 WORDS)

Inflatable cavernosal body device: feasibility and acute safety study in the canine model

OBJECTIVES

To determine the feasibility, safety, and acute mechanical reliability of a two-piece, implantable, inflatable cavernosal body compression device in the canine model.

METHODS

Six large male dogs underwent implantation of an inflatable cavernosal compression device consisting of an inflatable cuff and a pump reservoir. The device was implanted around the corpora cavernosa excluding the corpus spongiosum near the crura.

RESULTS

All devices were cycled three times a week for 2 months and radiographic evaluation found them to be mechanically reliable. Infusion cavernosometry with inflation of the device demonstrated greater than a 100% increase of intracorporeal pressure from baseline levels. Histologic assessment showed no adverse tissue effects on the penile tissue underlying the cuff or remote from the cuff in the penis and there was no development of distant thromboembolism.

CONCLUSIONS

The results from this study will form the basis of long-term canine studies to investigate physiologic changes on the canine erection and chronic safety and reliability of the device.

Three dimensional shape reconstruction and finite element analysis of femur before and after the cementless type of total hip replacement

Computerized tomography was used to reconstruct a shape, and stresses in three-dimensional objects were analysed. The human femur, which has a very irregular shape, was chosen as an object. CT image data of a cadaver femur were transferred to a computer, and an edge extraction program generated the cross-section of bone by specifying a range of CT values for each slice. Pixel data from the CT scan are converted into a vector of points (x, y, z) which can specify the boundaries of bone. Lateral surfaces are defined by stacking up the slices and making use of the vectorized data. Intermediate and oblique cross-sections can be obtained by an interpolation technique. The constructed model was used as input data for the finite element analysis. To understand the stress distributions before and after the cementless type of total hip replacement, a three-dimensional finite element stress analysis of the bone-implant system was carried out, assuming micromotions between the stem and the femur. The analysis was done for both frictionless and friction cases, modelling the contact point with a gap element having isotropic friction. The analysis shows that the stress is not concentrated on the femoral calcar when the friction coefficient is large.

Effect of gum chewing following food ingestion on the pH of interproximal dental plaque

Recent publications have suggested that chewing sorbitol- or sucrose-containing gum after a snack or meal can reduce development of caries by neutralizing dental plaque acids at interproximal sites in the dentition. To confirm these findings four volunteers wore appliances containing a miniature pH electrode. After plaque accumulation, subjects ingested a bowl of sugar-coated cereal with milk and 20 minutes later chewed a sorbitol-containing gum, a sucrose-containing gum, or did not chew anything for 20 minutes. After exposure to the cereal, the plaque pH fell within 20 minutes from approximately 6.4 to 4.8. Sorbitol gum caused the pH to rise to 5.5, while the sucrose gum caused the pH to rise to only 5.1. After cessation of chewing, the pH in all cases dropped to 4.5 or lower. No statistically significant difference could be shown between plaque pH changes with the various protocols. Gum chewing after eating caused only a transient elevation in plaque pH.