Ginsenoside Rb(1) prevents image navigation disability, cortical infarction, and thalamic degeneration in rats with focal cerebral ischemia

Oral administration of red ginseng powder before but not after transient forebrain ischemia prevents delayed neuronal death in gerbils. One neuroprotective molecule within red ginseng powder is ginsenoside Rb(1). The mechanism of action(s) of ginsenoside Rb(1) remains to be determined. We performed intracerebroventricular infusion of 0.6 microg/d ginsenoside Rb(1) before or after permanent occlusion of the left middle cerebral artery in stroke-prone spontaneous hypertensive rats. Ginsenoside Rb(1) significantly decreased escape latency on repeated trials of the Morris water maze test, throughout the first to fourth trial days at 2 and 4 weeks after MCA occlusion (P<.05, P<.01 or P<.001). The ratio of the infarcted area to the left hemispheric area in the groups treated with 0.6 microg/d of ginsenoside Rb(1) was significantly smaller than that in the saline-treated ischemic group (P<.05 or P<.001). The continuous infusion of ginsenoside Rb(1) (0.06 microg/d) was less effective and the other doses examined were ineffective in ameliorating ischemia-induced image navigation disability and reducing cortical infarct size. There were significant differences in neuron numbers in the ventroposterior thalamic nucleus and in the left-to-right ratio of the thalamic area between the saline-infused ischemic group and the ginsenoside Rb(1)-treated ischemic group (P<.05 or P<.01). Moreover, ginsenoside Rb(1) at concentrations of 0.1 to 100 fg/mL (0.09 to 90 fM), facilitated neurite extension and rescued cortical neurons from lethal damage caused by the free radical-promoting agent FeSO(4), in vitro (P<.05 or P<.01). These findings suggest that ginsenoside Rb(1) protects the cerebral cortex against lethal ischemic damage possibly by acting as a neurotrophic factor-like agent and by scavenging free radicals, which are overproduced in situ during and after brain ischemia. The final link between the in vivo neuroprotective action and the in vitro neurotrophic and antioxidant activities of ginsenoside Rb(1) remains to be determined.

Bacterial interactions in dental biofilm development

Recent analyses with ribosomal RNA-based technologies have revealed the diversity of bacterial populations within dental biofilms, and have highlighted their important contributions to oral health and disease. Dental biofilms are exceedingly complex and multispecies ecosystems, where oral bacteria interact cooperatively or competitively with other members. Bacterial interactions that influence dental biofilm communities include various different mechanisms. During the early stage of biofilm formation, it is known that planktonic bacterial cells directly attach to surfaces of the oral cavity or indirectly bind to other bacterial cells that have already colonized. Adherence through co-aggregation may be critical for the temporary retention of bacteria on dental surfaces, and may facilitate eventual bacterial colonization. It is likely that metabolic communication, genetic exchange, production of inhibitory factors (e.g., bacteriocins, hydrogen peroxide, etc.), and quorum-sensing are pivotal regulatory factors that determine the bacterial composition and/or metabolism. Since each bacterium can easily access a neighboring bacterial cell and its metabolites, genetic exchanges and metabolic communication may occur frequently in dental biofilms. Quorum-sensing is defined as gene regulation in response to cell density, which influences various functions, e.g., virulence and bacteriocin production. In this review, we discuss these important interactions among oral bacteria within the dental biofilm communities.

Predicting the probability for fall incidence in stroke patients using the Berg Balance Scale

This observational study investigated the relationship between balance, mobility and falls in 72 hemiplegic stroke inpatients, with the aim of developing a model for predicting fall risk. Fall history was recorded by interview, balance was assessed using the Berg Balance Scale (BBS) and activities of daily living were evaluated using the Functional Independence Measure (FIM). Variables differing between fallers and non-fallers were identified, and a stepwise regression analysis was performed to identify a combination of variables that effectively predicted fall status. Fallers (occasional and repeat; n = 27) had a shorter time from stroke onset, lower FIM scores on admission and discharge, lower BBS and Mini-Mental State Examination scores, a greater age and longer length of hospital stay compared with non-fallers (all differences were significant). A logistic model for predicting falls showed that BBS at admission was significantly related to falls, with fallers having lower BBS scores at admission (cut-off <or= 29; sensitivity 80%; specificity 78%). These data suggest BBS is a sensitive and specific measure for identifying stroke patients at risk of falling.

Functional difference of receptor-type protein tyrosine phosphatase zeta/beta isoforms in neurogenesis of hippocampal neurons

Receptor-type protein tyrosine phosphatase zeta/beta (RPTPzeta) is a transmembrane chondroitin sulfate proteoglycan (CSPG) and has been shown to play crucial roles in controlling axonal growth and neuronal migration. The RPTPzeta has two transmembranous isoforms, shorter receptor form of RPTPzeta (sRPTPzeta) and full-length receptor form of RPTPzeta (fRPTPzeta), but no studies have been reported about functional difference of these two isoforms. In the present study, therefore, we examined whether or not two RPTPzeta isoforms have different role in controlling dendritic morphology and synaptic number in cultured hippocampal neurons using the quantitative morphometrical analysis. Confocal microscopic observation showed that the immunoreactivity of RPTPzeta was observed throughout cells such as axons, growth cones, and dendrites at the early stages of neuronal culture, while it was seen predominantly on dendrites at the late stages. Western blotting analysis revealed that fRPTPzeta was mainly expressed at the early stages of culture and both RPTPzeta isoforms were expressed at late stages of culture. The overexpression of sRPTPzeta in hippocampal neurons increased the dendritic arborization without altering the average length of dendritic branches, whereas that of fRPTPzeta decreased the dendritic arborization and increased the average length of dendritic branches. The RNA interference of fRPTPzeta expression increased the dendritic arborization without altering the average length of dendritic branches. The overexpression of fRPTPzeta decreased the density of hippocampal dendritic synapses, but that of sRPTPzeta had no effects. Pleiotrophin, a ligand for RPTPzeta to interfere the phosphatase activity, increased the density of hippocampal dendritic synapses. Thus, the present study demonstrates that two transmembranous RPTPzeta isoforms have different functions for regulating dendritogenesis and synaptogenesis.

Analysis of soluble vascular endothelial growth factor receptor-1 secreted from cultured corneal and oral mucosal epithelial cell sheets in vitro

BACKGROUND

In clinical trials, eyes transplanted with cultured oral mucosal epithelial cell sheets have shown increased neovascularisation compared with eyes treated with cultured corneal epithelial cell sheets. As reported recently, soluble vascular endothelial growth factor receptor-1 (soluble VEGFr-1) is a main factor to maintain a corneal avascularity.

AIM

To investigate soluble VEGFr-1 of cultured corneal epithelial cells (CCE) and cultured oral mucosal epithelial cells (COE) in vitro.

METHODS

Rabbit corneal and oral mucosal epithelial cells were co-cultured with mitomycin C-treated NIH/3T3 cells on culture plates. After CCE and COE were multilayered, culture medium was replaced by basal medium and incubated. Protein secretion of soluble VEGFr-1 was assessed in conditioned medium from CCE and COE by ELISA. Angiogenic potential was examined by invasion, migration assays with human umbilical vein endothelial cells (HUVECs) in addition to recombinant soluble VEGFr-1.

RESULTS

CCE secreted a significantly higher amount of soluble VEGFr-1 than did COE. Recombinant soluble VEGFr-1 significantly suppressed HUVEC migration induced by COE, without suppression in CCE. In conclusion, these findings suggest that low protein levels of soluble VEGFr-1 may lead to corneal neovascularisation after COE sheet transplantation.

Sentinel lymph node detection in breast cancer patients by real-time virtual sonography constructed with three-dimensional computed tomography-lymphography

Abstract #1026

Background: Ultrasonography (US) is one tool for preoperative diagnosis of lymph node metastases in breast cancer. However, US cannot detect true sentinel lymph nodes (SLNs).&#x2028; Methods: We identified SLNs in 60 clinically node-negative breast cancer patients using a real-time virtual sonography (RVS) system to display in real time a virtual multi-planar reconstruction obtained from computed tomography (CT) volume data corresponding to the same cross-sectional image from US. CT volume data were obtained from our original three-dimensional CT lymphography (3DCT-LG), which accurately detects SLNs in breast cancer. SLN metastases were assessed by shape and visibility of the hilum. All patients underwent SLN biopsy and SLN metastases were examined pathologically.&#x2028; Results: In all 60 patients, we were able to detect the same SLNs visualized by 3DCT-LG. Suspicious SLN metastases were identified in 7 of the 60 patients, and 4 of 7 patients were pathologically positive. Positive predictive value was 57%. The remaining 53 patients displayed non-suspect SLNs in which absence of metastasis from the SLN was confirmed histologically. Overall accuracy was 95%.&#x2028; Conclusions: This is a first attempt at preoperatively identifying SLNs using US guided by the RVS system in breast cancer patients. Although evaluation of SLN metastases was unsatisfactory, this method may be useful for preoperative fine-needle aspiration cytology for diagnosis of SLN metastases.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 1026.

Differential modulation of diet-induced obesity and adipocyte functionality by human apolipoprotein E3 and E4 in mice

OBJECTIVE

Apolipoprotein E (apoE), a key protein in lipid metabolism, is highly expressed in adipose tissues. Studies have shown that human APOE*4 is associated with a lower body mass index but with a greater risk of coronary heart disease compared with other APOE alleles. To define the isoform-specific role of apoE in regulating the expandability and functionality of adipose tissues, we investigated the effects of diet-induced obesity in mice whose endogenous Apoe gene has been replaced by either the human APOE*3 or APOE*4 allele.

RESULTS

After 8 weeks on a Western-type high-fat diet, male APOE4 mice displayed impaired tolerance to glucose and fat overload compared with APOE3 mice. Subcutaneous fat tissues in APOE4 and APOE3 mice after high fat feeding were not different. In contrast, although epididymal fat tissues in APOE4 mice gained 30% less weight during the high fat feeding than in APOE3 mice, they showed impaired insulin-stimulated glucose uptake ex vivo. Epididymal APOE4 adipocytes were larger in size than APOE3 adipocytes, and expressed reduced levels of mRNA for peroxisome proliferator-activated receptor gamma2 and adiponectin, important markers of adipocyte functionality. Adenoviral expression of apoE3 in apoE-null culture adipocytes induced adiponectin mRNA in a dose-dependent manner, but the induction was significantly blunted in cells overexpressing apoE4. However, in contrast to the apoE3-expressing cells, Glut1, but not Glut4, expression levels were positively correlated with increased apoE4 mRNA, suggesting that apoE4 expression in adipocyte interferes in insulin-sensing pathways.

CONCLUSION

Dysfunctional epididymal adipose tissues contribute to the accelerated impairment of glucose tolerance in APOE4 mice fed a Western-type diet. Our results underscore the importance of functionality of individual fat depots rather than total fat mass as a determinant for metabolic disturbance during diet-induced obesity.

Effects of the time interval between clamping and linear stapling for resection of porcine small intestine

BACKGROUND

Although a wait of several seconds after clamping is recommended when an automatic stapler is used to achieve adequate hemostasis, this wait has not been experimentally clarified.

METHODS

To determine whether waiting is necessary between clamping and firing of a linear stapler, this study evaluated the number of staple line bleeding points and histologic changes in stapling sites of porcine small intestine (n = 46). It also assessed the ratio of dry to wet tissue weight (DW ratio) (n = 20) of porcine small intestine clamped between the prongs of a linear stapler. The sites were studied separately as follows: no wait with a four-row device (n = 12), no wait with a six-row device (n = 11), wait with a four-row device (n = 12), and wait with a six-row device (n = 11). The linear stapler was fired immediately after clamping in the no wait group and 1 min after clamping in the wait group.

RESULTS

The mean number of staple line bleeding points in 2 to 5 min with the six-row device and in 3 to 5 min with the four-row device after firing were significantly less in the wait group than in the no wait group using the same device (p < 0.05). Cross sections of staple lines showed a higher frequency of mucosal cutting in the no wait group than in the wait group for both the four-row and the six-row devices (both significant at p < 0.01). Although the mean wet tissue weights of anastomotic sites did not change in either group, the mean DW ratio was significantly less in the wait group than in the no wait group (p < 0.01).

CONCLUSIONS

A 1-min interval after clamping decreases the amount of clamped tissue. Waiting may thus be necessary to reduce bleeding from stapling sites, which may be related to a decrease in mucosal cutting.

Reduction of vitamin K concentration by salivary Bifidobacterium strains and their possible nutritional competition with Porphyromonas gingivalis

AIMS

To assess the possibility that bifidobacteria compete with Porphyromonas gingivalis for their mutual growth factor vitamin K. This study also examined whether salivary Bifidobacterium species decrease vitamin K concentration in the growth medium.

METHODS AND RESULTS

Sixty-five strains of Bifidobacterium were obtained from 20 of 24 periodontally healthy subjects. Bifidobacterium dentium was most frequently detected in the saliva of subjects, followed by Bifidobacterium adolescentis, Bifidobacterium longum, and Bifidobacterium urinalis. The growth of most Bifidobacterium isolates, except that of B. urinalis, was stimulated by vitamin K. Moreover, the isolates were capable of decreasing vitamin K after incubation, which suggests that bifidobacteria compete with P. gingivalis for vitamin K. In a co-culture, a representative strain -B. adolescentis S2-1 - inhibited the growth of P. gingivalis if it was inoculated in the medium before P. gingivalis.

CONCLUSIONS

B. adolescentis S2-1 decreased vitamin K concentration and inhibited the growth of P. gingivalis by possibly competing for the growth factor.

SIGNIFICANCE AND IMPACT OF THE STUDY

Salivary bifidobacteria may possess the potential to suppress the growth of P. gingivalis by reducing the growth factor(s) in the environment.

The inositol 1,4,5-trisphosphate receptor

Inositol 1,4,5-trisphosphate (InsP3) is a second messenger that releases Ca2+ from its intracellular stores. The InsP3 receptor has been purified and its cDNA has been cloned. We have found that the InsP3 receptor is identical to P400 protein, first identified as a protein enriched in cerebellar Purkinje cells. We have generated an L-fibroblast cell transfectant that produces cDNA-derived InsP3 receptors. The protein displays high affinity and specificity for InsP3. InsP3 induces greater Ca2+ release from membrane vesicles from transfected cells than from those from control L-fibroblasts. After incorporation of the purified InsP3 receptor into lipid bilayers InsP3-induced Ca2+ currents were demonstrated. These results suggest that the InsP3 receptor is involved in physiological Ca2+ release. Immunogold labelling using monoclonal antibodies against the receptor showed that it is highly concentrated on the smooth-surfaced endoplasmic reticulum and slightly on the outer nuclear membrane and rough endoplasmic reticulum; no labelling of Golgi apparatus, mitochondria and plasmalemma was seen. Cross-linking experiments showed that the receptor forms a homotetramer. The approximately 650 N-terminal amino acids are highly conserved between mouse and Drosophila, and this region contains the critical sequences for InsP3 binding. We have investigated the heterogeneity of the InsP3 receptor using the polymerase chain reaction and have found novel subtypes of the mouse InsP3 receptor that are expressed in a tissue-specific and developmentally specific manner.

Balloon catheter disruption of middle cerebral artery thrombus in conjunction with thrombolysis for the treatment of acute middle cerebral artery embolism

BACKGROUND AND PURPOSE

The goal of this study was to prospectively assess the feasibility, safety, and efficacy of balloon disruption of the middle cerebral artery (MCA) by using a deflated balloon catheter combined with an intra-arterial thrombolysis for the treatment of acute ischemic stroke.

MATERIALS AND METHODS

Seven consecutive patients with clinical findings of acute major-vessel stroke met our criteria and underwent balloon disruption of an MCA thrombus with a deflated balloon catheter. The balloon disruption was performed with a low-profile microballoon catheter. The microballoon was inflated in the distal carotid artery and then deflated and advanced just distal to the occlusion site in the MCA. Thereafter, an intra-arterial thrombolysis of the MCA was applied. The maximum time from the onset of symptoms to the start of treatment and maximum dosage of urokinase was 6 hours and 600,000 U. The outcome was classified as good for a modified Rankin Scale (mRS) score of 0 or 1, moderate for a score of 2 or 3, and poor for a score of 4 or 5.

RESULTS

Complete recanalization was achieved in 5 patients and partial recanalization in 3. Three patients recovered to an mRS score of 0 or 1; 3, to scores of 2 or 3; and 1, to a score of 4. No patients died. There was no major intracerebral hemorrhage.

CONCLUSIONS

The penetration of the MCA with a deflated balloon catheter combined with an intra-arterial thrombolysis may be a safe and effective treatment for acute ischemic stroke.

High PRL-3 expression in human gastric cancer is a marker of metastasis and grades of malignancies: an in situ hybridization study

Phosphatase of regenerating liver (PRL)-3, encoding a 22-kD low molecular weight tyrosine phosphatase, has been reported to be associated with metastasis of colorectal carcinoma. We assessed the levels of PRL-3 mRNA expression to know whether its up-regulation was involved in progression and metastasis of gastric carcinoma. Levels of PRL-3 expression in 94 human gastric adenocarcinomas and 54 matched lymph node metastases were detected by in situ hybridization and compared with clinicopathological characteristics including prognosis. High PRL-3 expression was detected in 36.2% of primary gastric carcinoma (with nodal metastasis, 55.6%; without nodal metastasis, 10%; P < 0.001) and in 74.1% of lymph node metastases. The incidence of high PRL-3 expression in lymph node metastasis was significantly higher than in primary tumors (P < 0.044). Moreover, high expression of PRL-3 was closely associated with tumor size, lymphatic invasion, venous invasion, extent of lymph node metastasis, and tumor stage. These results suggest that high PRL-3 expression may participate in the progression and metastasis of gastric carcinoma. PRL-3 might be a novel molecular marker for aggressive gastric cancer.

Impact of glycerol gateway molecule in adipocytes

Glycerol is one of the essential nutrients in the mammalian body. Glycerol released from adipocytes is delivered to the liver and used for gluconeogenesis. The molecular mechanism of glycerol transport across the cell membrane remains unclear. AQPadipose, which we identified in human adipose cDNA project and later found to be human AQP7, is expressed in adipose tissue, and upregulated during fasting. AQP7 belongs to the aquaglyceroporin subfamily to permealize glycerol as well as water. Loss of function mutation of AQP7 in human caused disturbance of normal rise of plasma glycerol. Disruption of AQP7 gene in mice resulted in profound hypoglycemia during prolonged fasting because of impaired glycerol supply to the liver. In obesity, AQP7 is overexpressed in visceral fat,accompanied by portal hyperglycerolemia and systemic hyperglycemia. Considered together, these works indicate that AQP7 functions as a glycerol gateway molecule in adipocytes.

Earlier onset of neutrophil-mediated inflammation in the ultraviolet-exposed skin of mice deficient in myeloperoxidase and NADPH oxidase

OBJECTIVE AND DESIGN

This study examined the role of neutrophil-derived reactive oxygen species (ROS) in neutrophil recruitment into ultraviolet B (UVB)-exposed skin of mice.

METHODS

Mouse dorsal skin was irradiated with UVB (600 mJ/cm2). Accumulation of neutrophils within the inflammatory sites was observed histochemically. Keratinocyte-derived chemokine (KC) and macrophage inflammatory protein 2 (MIP-2) were quantified, and in vivo chemotaxis of neutrophils toward KC and MIP-2 was examined.

RESULTS

UVB exposure of mice deficient in myeloperoxidase (MPO), NADPH oxidase, or both, caused skin neutrophil infiltration peaking at 60, 48, and 48 h, respectively, which was earlier than the 72-h peak in wild-type mice. MIP-2 level was higher in mutant than wild-type mice. Mutant neutrophils produced more MIP-2 in vitro. Neutrophil migration toward a localized source of KC was higher in mutant than wild type mice. NADPH oxidase deficiency had a greater effect on migration than MPO deficiency.

CONCLUSIONS

These results suggest that ROS produced by neutrophils regulate expression of MIP-2 and migration of neutrophils toward KC. This may explain the earlier infiltration of mutant neutrophils in response to UVB.

Blockade of Angiotensin II type-1 receptor reduces oxidative stress in adipose tissue and ameliorates adipocytokine dysregulation

Dysregulated production of adipocytokines may be involved in the development of atherosclerotic cardiovascular disease in metabolic syndrome and chronic kidney disease (CKD) associated with metabolic syndrome. The aim of this study was to determine the effects of treatment with angiotensin II (Ang II) type-1 receptor blocker (ARB) on the regulation of adipocytokines. Olmesartan, an ARB, significantly blunted the age- and body weight-associated falls in plasma adiponectin both in genetically and diet-induced obese mice, without affecting body weight, but had no effect on plasma adiponectin levels in lean mice. Olmesartan also ameliorated dysregulation of adipocytokines in obesity, such as tumor necrosis factor-alpha, plasminogen activator inhibitor-1, monocyte chemotactic protein-1, and serum amyloid A3. Olmesartan significantly reduced reactive oxygen species originating from accumulated fat and attenuated the expression of nicotinamide adenine dinucleotide phospho hydrogenase oxidase subunits in adipose tissue. In cultured adipocytes, olmesartan acted as an antioxidant and improved adipocytokine dysregulation. Our results indicate that blockade of Ang II receptor ameliorates adipocytokine dysregulation and that such action is mediated, at least in part, by targeting oxidative stress in obese adipose tissue. Ang II signaling and subsequent oxidative stress in adipose tissue may be potential targets for the prevention of atherosclerotic cardiovascular disease in metabolic syndrome and also in metabolic syndrome-based CKD.

DNA fingerprinting of isolates of Streptococcus mutans by pulsed-field gel electrophoresis

Forty isolates and five standard laboratory strains, representing serotypes c, e and f of Streptococcus mutans were analyzed by pulsed-field gel electrophoresis (PFGE) after digestion of the genomic DNA with BssH II. The digestion patterns of standard laboratory strains were characteristic of serotypes c, e and f. Serotypes c and f generated diagnostic DNA fragments of approximately 145 kbp and of approximately 130-175 kbp in length, respectively. Serotype e generated a ladder of at least 14 fragments of 15-155 kbp in length. The digestion patterns of isolates were essentially similar to those of the standard laboratory strains. The patterns of almost all isolates obtained from a single individual were identical, but patterns of a few different types were also observed among isolates obtained from two individuals. Digestion with BssH II revealed differences among isolates obtained from different individuals. We used differences in banding patterns among isolates to construct a dendrogram. The dendrogram included two major clusters, one that consisted of isolates of serotypes c and f, and an other that consisted of isolates of serotype e. Our results indicate that BssH II is a useful enzyme for distinguishing among isolates of S. mutans and that digestion patterns obtained by PFGE can be used for chromosomal DNA fingerprinting.