bluuebunny/crossref_metadata_2025 huggingface dataset:
Characterization of Nob3, a major quantitative trait locus for obesity and hyperglycemia on mouse chromosome 1
Authors: Vogel Heike , Nestler Matthias , Rüschendorf Franz , Block Marcel-Dominique , Tischer Sina , Kluge Reinhart , Schürmann Annette , Joost Hans-Georg , Scherneck Stephan
Published: May 2009

New Zealand obese (NZO) mice present a metabolic syndrome of obesity, insulin resistance, and diabetes. To identify chromosomal segments associated with these traits, we intercrossed NZO mice with the lean and diabetes-resistant C57BL/6J (B6) strain. Obesity and hyperglycemia in the (NZO×B6)F2 intercross population were predominantly due to a broad quantitative trait locus (QTL) on chromosome 1 ( Nob3; logarithm of the odds score 16.1, 16.0, 4.0 for body weight, body fat, and blood glucose, respectively), producing a difference between genotypes of 12.7 or 5.2 g of body weight and 12.0 or 4.0 g of body fat in females or males, respectively. In addition, significant QTL on chromosomes 3 and 13 and suggestive QTL on chromosomes 4, 6, 9, 12, 14, and 19 contributed to the obese phenotype. Distal chromosome 5 was significantly linked with plasma cholesterol (LOD score 10.7). Introgression of two segments of Nob3 into B6 confirmed the adipogenic effect of the QTL and suggested the presence of at least one causal gene. Haplotype mapping reduced the critical region of the distal part of the QTL to 31 Mbp containing the potential candidates Nr1i3, Apoa2, Atp1a2, Prox1, and Hsd11b1. We conclude that obesity and hyperglycemia of NZO is to a large part caused by variant genes located in Nob3 on chromosome 1. Since these exert robust effects on a B6 background, the QTL Nob3 is a prime target for identification of a novel diabesity gene.
Genomic analyses reveal a conserved glutathione homeostasis pathway in the invertebrate chordate Ciona intestinalis
Authors: Nava Gerardo M. , Lee David Y. , Ospina Javier H. , Cai Shi-Ying , Gaskins H. Rex
Published: May 2009

The major thiol redox buffer glutathione (l-γ-glutamyl-l-cysteinylglycine, GSH) is central to cell fate determination, and thus, associated metabolic and regulatory pathways are exquisitely sensitive to a wide range of environmental cues. An imbalance of cellular redox homeostasis has emerged as a pathologic hallmark of a diverse range of human gene-environment disorders. Despite the central importance of GSH in cellular homeostasis, underlying genetic regulatory pathways remain poorly defined. This report describes the annotation and expression analysis of genes contributing to GSH homeostasis in the invertebrate chordate Ciona intestinalis . A core pathway comprising 19 genes contributing to the biosynthesis of GSH and its use as both a redox buffer and a conjugate in phase II detoxification as well as known transcriptional regulators were analyzed. These genes exhibit a high level of sequence conservation with corresponding human, rat, and mouse homologs and were expressed constitutively in tissues of adult animals. The GSH biosynthetic genes Gclc and Gclm were also responsive to the prototypical antioxidant tert-butylhydroquinone. The present evidence of a conserved GSH homeostasis pathway in C. intestinalis together with its phylogenetic position as a basal chordate and lifestyle as a filter feeder constantly exposed to natural marine toxins introduces this species as an important animal model for defining molecular mechanisms that potentially underlie genetic susceptibility to environmentally associated stress.
Large-scale mRNA analysis of female skeletal muscles during 60 days of bed rest with and without exercise or dietary protein supplementation as countermeasures
Authors: Chopard A. , Lecunff M. , Danger R. , Lamirault G. , Bihouee A. , Teusan R. , Jasmin B. J. , Marini J. F. , Leger J. J.
Published: May 2009

Microgravity has a dramatic impact on human physiology, illustrated in particular, with skeletal muscle impairment. A thorough understanding of the mechanisms leading to loss of muscle mass and structural disorders is necessary for defining efficient clinical and spaceflight countermeasures. We investigated the effects of long-term bed rest on the transcriptome of soleus (SOL) and vastus lateralis (VL) muscles in healthy women (BRC group, n = 8), and the potential beneficial impact of protein supplementation (BRN group, n = 8) and of a combined resistance and aerobic training (BRE group, n = 8). Gene expression profiles were obtained using a customized microarray containing 6,681 muscles-relevant genes. A two-class statistical analysis was applied on 2,103 genes with consolidated expression in BRC, BRN, and BRE groups. We identified 472 and 207 mRNAs whose expression was modified in SOL and VL from BRC group, respectively. Further clustering analysis, identifying relevant biological mechanisms and pathways, reported five main subclusters. Three are composed of upregulated mRNAs involved mainly in nucleic acid and protein metabolism, and two made up of downregulated transcripts encoding components involved in energy metabolism. Exercise countermeasure demonstrated drastic compensatory effects, decreasing the number of differentially expressed mRNAs by 89 and 96% in SOL and VL, respectively. In contrast, nutrition countermeasure had moderate effects and decreased the number of differentially-expressed transcripts by 40 and 25% in SOL and VL. Together, these data present a systematic, global and comprehensive view of the adaptive response of female muscle to long-term atrophy.
Comparing Multicarrier Ambiguity Resolution Methods for Geometry‐Based GPS and Galileo Relative Positioning and Their Application to Low Earth Orbiting Satellite Attitude Determination
Authors: O′Keefe Kyle , Petovello Mark , Cao Wei , Lachapelle Gérard , Guyader Eric
Published: May 2009

This paper presents an evaluation of several GNSS multicarrier ambiguity (MCAR) resolution techniques for the purpose of attitude determination of low earth orbiting satellites (LEOs). It is based on the outcomes of the study performed by the University of Calgary and financed by the European 6th Framework Programme for Research and Development as part of the research project PROGENY. The existing MCAR literature is reviewed and eight possible variations of the general MCAR processing scheme are identified based on two possible options for the mathematical model of the float solution, two options for the estimation technique used for the float solution, and finally two possible options for the ambiguity resolution process. The two most promising methods, geometry‐based filtered cascading and geometry‐based filtered LAMBDA, are analysed in detail for two simulated users modelled after polar orbiting LEOs through an extensive covariance simulation. Both the proposed Galileo constellation and Galileo used in conjunction with the GPS constellation are tested and results are presented in terms of probabilities of correct ambiguity resolution and float and fixed solution baseline accuracies. The LAMBDA algorithm is shown to outperform the cascading method, particularly in the single‐frequency dual‐GNSS system case. Secondly, more frequencies and multiple GNSS always offer improvement, but the single‐frequency dual‐system case is found to have similar performance to the dual‐frequency single‐system case.
Endogenous Tumor Suppression Mediated by PTEN Involves Survivin Gene Silencing
Authors: Guha Minakshi , Plescia Janet , Leav Irwin , Li Jing , Languino Lucia R. , Altieri Dario C.
Published: May 2009

Endogenous tumor suppression provides a barrier against oncogenesis, but the molecular requirements of this process are not well understood. Here, we show that the dual specificity phosphatase PTEN, a gene almost universally altered in human tumors, silences the expression of survivin, an essential regulator of cell division and apoptosis in cancer. This pathway is independent of p53, involves active repression of survivin gene transcription, and is mediated by direct occupancy of the survivin promoter by FOXO1 and FOXO3a factors. Conditional deletion of PTEN in the mouse prostate causes deregulated induction of survivin before full-blown transformation in vivo, whereas expression of survivin and PTEN is inversely correlated in cancer patients. Therefore, silencing the survivin gene is an essential requirement of endogenous PTEN tumor suppression. [Cancer Res 2009;69(12):4954–8]
DNMT3B Expression Might Contribute to CpG Island Methylator Phenotype in Colorectal Cancer
Authors: Nosho Katsuhiko , Shima Kaori , Irahara Natsumi , Kure Shoko , Baba Yoshifumi , Kirkner Gregory J. , Chen Li , Gokhale Sumita , Hazra Aditi , Spiegelman Donna , Giovannucci Edward L. , Jaenisch Rudolf , Fuchs Charles S. , Ogino Shuji
Published: May 2009

Purpose: DNA methyltransferase-3B (DNMT3B) plays an important role in de novo CpG island methylation. Dnmt3b can induce colon tumor in mice with methylation in specific CpG islands. We hypothesized that cellular DNMT3B level might influence the occurrence of widespread CpG island methylation (i.e., the CpG island methylator phenotype, CIMP) in colon cancer.

Experimental Design: Utilizing 765 colorectal cancers in two cohort studies, we detected DNMT3B expression in 116 (15%) tumors by immunohistochemistry. We assessed microsatellite instability, quantified DNA methylation in repetitive long interspersed nucleotide element-1 (LINE-1) by Pyrosequencing, eight CIMP-specific promoters [CACNA1G, CDKN2A (p16), CRABP1, IGF2, MLH1, NEUROG1, RUNX3, and SOCS1], and eight other CpG islands (CHFR, HIC1, IGFBP3, MGMT, MINT1, MINT31, p14, and WRN) by real-time PCR (MethyLight).

Results: Tumoral DNMT3B overexpression was significantly associated with CIMP-high [≥6/8 methylated CIMP-specific promoters; odds ratio (OR), 3.34; 95% confidence interval, 2.11-5.29; P < 0.0001]. The relations between DNMT3B and methylation in 16 individual CpG islands varied substantially (OR, 0.80-2.96), suggesting variable locus-to-locus specificities of DNMT3B activity. DNMT3B expression was not significantly related with LINE-1 hypomethylation. In multivariate logistic regression, the significant relation between DNMT3B and CIMP-high persisted (OR, 2.39; 95% confidence interval, 1.11-5.14; P = 0.026) after adjusting for clinical and other molecular features, including p53, β-catenin, LINE-1, microsatellite instability, KRAS, PIK3CA, and BRAF. DNMT3B expression was unrelated with patient outcome, survival, or prognosis.

Conclusions: Tumoral DNMT3B overexpression is associated with CIMP-high in colorectal cancer. Our data support a possible role of DNMT3B in nonrandom de novo CpG island methylation leading to colorectal cancer.
Nitric Oxide Synthase Inhibition Enhances the Tumor Vascular-Damaging Effects of Combretastatin A-4 3-O-Phosphate at Clinically Relevant Doses
Authors: Tozer Gillian M. , Prise Vivien E. , Lewis Gemma , Xie Shaoping , Wilson Ian , Hill Sally A.
Published: May 2009

Purpose: The therapeutic potential of combining the prototype tumor vascular-disrupting agent combretastatin A-4 3-O-phosphate (CA-4-P) with systemic nitric oxide synthase (NOS) inhibition was investigated preclinically.

Experimental Design: Vascular response (uptake of 125I-labeled iodoantipyrine; laser Doppler flowmetry) and tumor response (histologic necrosis; cytotoxicity and growth delay) were determined.

Results: Inducible NOS selective inhibitors had no effect on blood flow in the P22 rat sarcoma. In contrast, the non–isoform-specific NOS inhibitor Nω-nitro- l-arginine (l-NNA; 1 and 10 mg/kg i.v. or chronic 0.1 or 0.3 mg/mL in drinking water) decreased the P22 blood flow rate selectively down to 36% of control at 1 hour but did not induce tumor necrosis at 24 hours. CA-4-P, at clinically relevant doses, decreased the P22 blood flow rate down to 6% of control at 1 hour for 3 mg/kg but with no necrosis induction. However, l-NNA administration enhanced both CA-4-P–induced tumor vascular resistance at 1 hour (chronic l-NNA administration) and necrosis at 24 hours, with 45% or 80% necrosis for 3 and 10 mg/kg CA-4-P, respectively. Bolus l-NNA given 3 hours after CA-4-P was the most effective cytotoxic schedule in the CaNT mouse mammary carcinoma, implicating a particular enhancement by l-NNA of the downstream consequences of CA-4-P treatment. Repeated dosing of l-NNA with CA-4-P produced enhanced growth delay over either treatment alone in P22, CaNT, and spontaneous T138 mouse mammary tumors, which represented a true therapeutic enhancement.

Conclusions: The combination of NOS inhibition with CA-4-P is a promising approach for targeting tumor vasculature, with relevance for similar vascular-disrupting agents in development.
Sagopilone Inhibits Breast Cancer Bone Metastasis and Bone Destruction Due to Simultaneous Inhibition of Both Tumor Growth and Bone Resorption
Authors: Strube Anne , Hoffmann Jens , Stepina Elizaveta , Hauff Peter , Klar Ulrich , Käkönen Sanna-Maria
Published: May 2009

Purpose: Bone metastases have a considerable impact on quality of life in patients with breast and other cancers. Tumors produce osteoclast-activating factors, whereas bone resorption promotes the growth of tumor cells, thus leading to a “vicious cycle” of bone metastasis. Sagopilone, a novel, fully synthetic epothilone, inhibits the growth of breast cancer cells in vitro and in vivo, and here we report its activity in the MDA-MB-231(SA) breast cancer bone metastasis mouse model.

Experimental Design: The potency of sagopilone was determined in treatment models simulating the adjuvant (preventive) and metastatic (therapeutic) settings in the clinic.

Results: We showed that sagopilone inhibited tumor burden and bone destruction, in addition to reducing tumor-induced cachexia and paraplegia. The reduction in osteolytic lesions, tumor growth in bone, and weight loss was statistically significant in the preventive model compared with the vehicle group. In the therapeutic model, sagopilone treatment significantly lowered the number of activated osteoclasts and significantly reduced the osteolytic lesion area, bone volume loss, and bone resorption compared with vehicle treatment while simultaneously inhibiting tumor burden. An in vitro assay confirmed that sagopilone inhibited osteoclast activation without cytotoxic effects, whereas paclitaxel resulted in lower inhibition and high levels of cytotoxicity.

Conclusions: Sagopilone seems to inhibit the vicious cycle at both the tumor growth and bone resorption stages, suggesting the possibility for substantial benefit in the treatment of patients with breast cancer at risk from bone metastases or with bone lesions already present. Phase II clinical trials with sagopilone in patients with breast cancer are ongoing.
FOXA1 Is a Potential Oncogene in Anaplastic Thyroid Carcinoma
Authors: Nucera Carmelo , Eeckhoute Jerome , Finn Stephen , Carroll Jason S. , Ligon Azra H. , Priolo Carmen , Fadda Guido , Toner Mary , Sheils Orla , Attard Marco , Pontecorvi Alfredo , Nose Vânia , Loda Massimo , Brown Myles
Published: May 2009

Purpose: FOXA1 is a mammalian endodermal transcription factor belonging to the human forkhead box gene family that plays a role in certain tumor types. Here, we investigated the potential role of FOXA1 in human thyroid carcinomas.

Experimental Design: We examined the level of FOXA1 expression and gene copy number by immunohistochemistry and fluorescence in situ hybridization, respectively, in a cohort of benign and malignant thyroid tumors. In addition, we examined the role of FOXA1 in the proliferation of an undifferentiated thyroid carcinoma cell line by short hairpin RNA-mediated silencing.

Results: We show that FOXA1 is overexpressed in human anaplastic thyroid carcinomas (ATC). In addition, we identify FOXA1 DNA copy number gain within the 14q21.1 locus in both an ATC cell line and human ATC cases. Silencing of FOXA1 in an ATC cell line causes G1 growth arrest and reduction of cell proliferation. Moreover, we observe a potential link between FOXA1 and the cell cycle machinery by identifying p27kip1 up-regulation on FOXA1 silencing.

Conclusions: FOXA1 is overexpressed in aggressive thyroid cancers and involved in cell cycle progression in an ATC cell line. Therefore, FOXA1 may be an important oncogene in thyroid tumorigenesis and a potential new therapeutic target for the treatment of anaplastic thyroid cancers.
Integrative Analysis of Cyclin Protein Levels Identifies Cyclin B1 as a Classifier and Predictor of Outcomes in Breast Cancer
Authors: Agarwal Roshan , Gonzalez-Angulo Ana-Maria , Myhre Simen , Carey Mark , Lee Ju-Seog , Overgaard Jens , Alsner Jan , Stemke-Hale Katherine , Lluch Ana , Neve Richard M. , Kuo Wen Lin , Sorlie Therese , Sahin Aysegul , Valero Vicente , Keyomarsi Khandan , Gray Joe W. , Borresen-Dale Anne-Lise , Mills Gordon B. , Hennessy Bryan T.
Published: May 2009

Purpose: We studied the expression levels of cyclins B1, D1, and E1 and the implications of cyclin overexpression for patient outcomes in distinct breast cancer subtypes defined by clinical variables and transcriptional profiling.

Experimental Design: The expression levels of cyclins B1, D1, and E1 were quantified in 779 breast tumors and 53 cell lines using reverse phase protein arrays and/or transcriptional profiling.

Results: Whereas cyclin E1 overexpression was a specific marker of triple-negative and basal-like tumors, cyclin B1 overexpression occurred in poor prognosis hormone receptor–positive, luminal B and basal-like breast cancers. Cyclin D1 overexpression occurred in luminal and normal-like cancers. Breast cancer subgroups defined by integrated expression of cyclins B1, D1, and E1 correlated significantly (P < 0.000001) with tumor subtypes defined by transcriptional profiling and clinical criteria. Across three hormone receptor–positive data sets, cyclin B1 was the dominant cyclin associated with poor prognosis in univariate and multivariate analyses. Although CCNE1 was present in significantly higher copy numbers in basal-like versus other subtypes (ANOVA P < 0.001), CCNB1 gene copy number did not show gain in breast cancer. Instead, cyclin B1 expression was increased in tumors with co-occurrence of TP53 mutations and MYC amplification, a combination that seems to characterize basal-like and luminal B tumors. CCNB1 gene expression was significantly correlated with PLK, CENPE, and AURKB gene expression.

Conclusion: Cyclins B1, D1, and E1 have distinct expressions in different breast cancer subtypes. Novel PLK, CENPE, and AURKB inhibitors should be assessed for therapeutic utility in poor prognosis cyclin B1–overexpressing breast cancers.
3,3′-Diindolylmethane Enhances the Efficacy of Butyrate in Colon Cancer Prevention through Down-Regulation of Survivin
Authors: Bhatnagar Namrata , Li Xia , Chen Yue , Zhou Xudong , Garrett Scott H. , Guo Bin
Published: May 2009

Butyrate is an inhibitor of histone deacetylase (HDAC) and has been extensively evaluated as a chemoprevention agent for colon cancer. We recently showed that mutations in the adenomatous polyposis coli (APC) gene confer resistance to HDAC inhibitor–induced apoptosis in colon cancers. Here, we show that APC mutation rendered colon cancer cells resistant to butyrate-induced apoptosis due to the failure of butyrate to down-regulate survivin in these cells. Another cancer-preventive agent, 3,3′-diindolylmethane (DIM), was identified to be able to down-regulate survivin in colon cancers expressing mutant APC. DIM inhibited survivin mRNA expression and promoted survivin protein degradation through inhibition of p34cdc2-cyclin B1–mediated survivin Thr34 phosphorylation. Pretreatment with DIM enhanced butyrate-induced apoptosis in colon cancer cells expressing mutant APC. DIM/butyrate combination treatment induced the expression of proapoptotic Bax and Bak proteins, triggered Bax dimerization/activation, and caused release of cytochrome c and Smac proteins from mitochondria. Whereas overexpression of survivin blocked DIM/butyrate–induced apoptosis, knocking down of survivin by small interfering RNA increased butyrate-induced apoptosis in colon cancer cells. We further showed that DIM was able to down-regulate survivin and enhance the effects of butyrate in apoptosis induction and prevention of familial adenomatous polyposis in APCmin/+ mice. Thus, the combination of DIM and butyrate is potentially an effective strategy for the prevention of colon cancer.
Synergistic Growth Inhibition of Squamous Cell Carcinoma of the Head and Neck by Erlotinib and Epigallocatechin-3-Gallate: The Role of p53-Dependent Inhibition of Nuclear Factor-κB
Authors: Amin A.R.M. Ruhul , Khuri Fadlo R. , Chen Zhuo (Georgia) , Shin Dong M.
Published: May 2009

We have previously reported that the green tea polyphenol epigallocatechin-3-gallate (EGCG) and the epidermal growth factor receptor-tyrosine kinase inhibitor erlotinib had synergistic growth-inhibitory effects in cell culture and a nude mouse xenograft model of squamous cell carcinoma of the head and neck. However, the mechanism of their antitumor synergism is not fully understood. In the current study, we investigate the mechanism of their synergistic growth-inhibitory effects. The treatment of squamous cell carcinoma of the head and neck cell lines with erlotinib time-dependently increased the expression of cell cycle regulatory proteins p21 and p27 and apoptosis regulatory protein Bim. EGCG alone had very little or no effect on the expression of these proteins among the cell lines. However, simultaneous treatment with EGCG and erlotinib strongly inhibited erlotinib-induced expression of p21 and p27 without affecting the expression of Bim. Moreover, erlotinib increased the expression of p53 protein, the ablation of which by short hairpin RNA strongly inhibited EGCG- and erlotinib-mediated growth inhibition and the expression of p21, p27, and Bim. In addition, combined treatment with erlotinib and EGCG inhibited the protein level of p65 subunit of nuclear factor-κB and its transcriptional target Bcl-2, but failed to do so in cells with ablated p53. Taken together, our results, for the first time, suggest that erlotinib treatment activates p53, which plays a critical role in synergistic growth inhibition by erlotinib and EGCG via inhibiting nuclear factor-κB signaling pathway. Characterizing the underlying mechanisms of EGCG and erlotinib synergism will provide an important rationale for chemoprevention or treatment trials using this combination.
In vitro Study of the Effects of Lens Extract on Rat Retinal Neuron Survival and Neurite Outgrowth
Authors: Wang Yanhua , Wang Yi , Wang Dongwu , Wu Nan , Liu Dongning , Yin Zhengqin , Zhu Meidong
Published: May 2009

Background: Optic nerve regeneration has previously been achieved by injuring the lens, which results in the release of lentogenic factors. However, these lentogenic factors are still unknown. Objectives: To investigate what were the lentogenic factors by examining the effects of lens extract and macrophage-conditioned medium (MCM) on the survival and the neurite outgrowth of rat retinal neurons in vitro. Methods: Retinal neurons were cultured in 4 groups: (1) Dulbecco’s modified Eagle’s medium (DMEM), (2) DMEMcontaining lens extract, (3) DMEM containing macrophage-conditioned medium (MCM-D), (4) DMEM and medium from macrophages grown with lens extract (MCM-L). Neurite outgrowth and neuron survival time were observed. The density of retinal neurons with neurites and the longest neurites of the cells were measured on days 1, 3 and 5. Results: Retinal neurons survive for 12–14 days in DMEM containing lens extract. However, the cells only survive for 6 days in DMEM and only 7 days in DMEM containing MCM-L or MCM-D. The present results indicate that lens extract may directly promote survival of rat retinal neurons and neurite outgrowth in vitro. The MCM also promoted cell survival and neurite outgrowth but its effects were weaker than that of the lens extract. We postulate that lens extract exerts its effect by direct neurotrophic effects and/or indirectly by activating macrophagesin vitro.
Preservation of Glutamate Immunoreactivity and Ischemic Change in Photoreceptor Inner Segments in the Retina after Different Protocols of Perfusion Fixation
Authors: Sasoh Mikio , Ma Ning , Uji Yukitaka
Published: May 2009

Aim: The present study investigates whether glutamate immunoreactivity (IR) in the cat outer retina, which is devoid of blood vessels, can be well preserved by perfusion fixation. Methods: Adult cats were perfused intracardially for 1, 5, 10, 15 and 30 min with physiological saline and were subsequently perfused with a mixture of 1% glutaraldehyde and 4% formaldehyde. After the fixation, the retinas were immunocytochemically examined. Results: The photoreceptor inner segments in the retina, which was perfused by saline for 1 and 5 min prior to fixation, showed no glutamate IR. However, those in the retina which was perfused by saline for 10 min showed moderate glutamate IR as found in the retina fixed by immersion. The glutamate IR in the inner segments decreased with a saline perfusion of more than 10 min. Conclusions: Perfusion fixation can well preserve glutamate IR even in the outer retina including the inner segments.
Evaluation of Modified Portable Digital Camera for Screening of Diabetic Retinopathy
Authors: Chalam Kakarla V. , Brar Vikram S. , Keshavamurthy Ravi
Published: May 2009

Aims: To describe a portable wide-field noncontact digital camera for posterior segment photography. Methods: The digital camera has a compound lens consisting of two optical elements (a 90-dpt and a 20-dpt lens) attached to a 7.2-megapixel camera. White-light-emitting diodes are used to illuminate the fundus and reduce source reflection. The camera settings are set to candlelight mode, the optic zoom standardized to ×2.4 and the focus is manually set to 3.0 m. Results: The new technique provides quality wide-angle digital images of the retina (60°) in patients with dilated pupils, at a fraction of the cost of established digital fundus photography. Conclusions: The modified digital camera is a useful alternative technique to acquire fundus images and provides a tool for screening posterior segment conditions, including diabetic retinopathy in a variety of clinical settings.
TAT Peptides Mediated Small Interfering RNA Delivery to Huh-7 Cells and Efficiently Inhibited Hepatitis C Virus RNA Replication
Authors: Meng Shuang , Wei Baojun , Xu Ruihuan , Zhang Kuo , Wang Lunan , Zhang Rui , Li Jinming
Published: May 2009

Objective: To observe whether or not the small-interfering RNA (siRNA) that conjugated with human immunodeficiency virus type 1 (HIV-1) TAT47–57 peptides can enter Huh-7 cells and efficiently silence hepatitis C virus (HCV) infection in cell culture. Methods: siRNA targeting the highly conserved stem loop IV of the HCV 5′ untranslated region (5′UTR) was conjugated to TAT47–57 peptides via the crosslinker sulfosuccinimidyl-4-(p-maleimidophenyl)-butyrate, and then the conjugates were added to the Huh-7 cell culture. Firefly luciferase activity and HCV RNA were asssessed using a luciferase assay reagent and real-time reverse transcript polymerase chain reaction, respectively. Results: The expression of firefly luciferase in HCV replicons and the concentration of HCV RNA were downregulated by siRNA-TAT47–57, and siRNA-TAT47–57 mediated RNA interfering activity which was directly correlated with increasing concentrations of the siRNA-TAT47–57 conjugate used. Conclusion: Cell-penetrating peptides such as HIV-1 TAT are an effective method for the delivery of siRNA targeted at 5′UTR of HCV in mammalian cells.
Evaluation of Succinylated Collagen Bandage Lenses in Corneal Healing by the Expression of Matrix Metalloproteinases (MMP-2 and MMP-9) in Tear Fluid
Authors: Hadassah J. , Bhuvaneshwari Namita , Rao Urmila , Sehgal P.K.
Published: May 2009

Aim: The aim of the study was to evaluate the efficacy of succinylated collagen bandage lenses (SCBL) in the healing of various corneal conditions. Methods: Clinical evaluation of SCBL was carried out in patients with corneal ulcer (CU), recurrent corneal erosions (RCE), dry eyes (DE) and corneal lesion (CL). In each patient, corneal healing was studied by subjective clinical assessment such as pain, redness, watering, discomfort, irritation, foreign body sensation, biochemical analysis of tear fluid (TF) for protein content, expression of matrix metalloproteinases (MMPs) by gelatin zymography (GZ) and Western blotting (WB). In both GZ and WB bands were quantified and analyzed by gel documentation analyzer. Results: Subjective clinical assessment of CU, RCE, DE and CL patients after treatment with SCBL showed significant reduction in the symptoms, patients felt comfortable with SCBL with no change in visual acuity, indicating complete transparency of SCBL. Protein content was very high on day 1 among all the patients, and it reduced gradually after treatment with SCBL signifying corneal healing. GZ of TF showed the expression of both MMP-2 and MMP-9 on day 3. There was significant reduction in MMP-2 and MMP-9 expression on day 7 in all cases, it decreased considerably on day 14 and was almost negligible on day 21 reflecting corneal healing with SCBL. Conclusion: Our study indicated that SCBL significantly reduces symptoms of irritation and discomfort in the cornea. It maintains visual acuity, controls inflammation and watering in the eye reflecting corneal healing in all cases studied by us. SCBL represents a promising alternative to other bandage lenses in corneal healing.
Macular Capillary Blood Flow in Patients with Diffuse Diabetic Macular Edema without Vitreomacular Traction
Authors: Park Jung Hyun , Woo Se Joon , Ha Youn Jin , Yu Hyeong Gon
Published: May 2009

Background: To evaluate macular microcirculation in patients with unilateral diffuse diabetic macular edema (DME) in order to determine whether the alteration in macular microcirculation is associated with development of diffuse DME without vitreomacular traction. Methods: According to the presence of epiretinal membrane (ERM), 27 patients having unilateral diffuse DME were divided into DME without ERM (non-ERM-DME group, n = 12) and with ERM (ERM-DME group, n = 15). Twelve patients with macular edema associated with unilateral branch vein obstruction (BVO) and 10 nondiabetic healthy subjects were enrolled as controls. Macular blood flow measured by Heidelberg retinal flowmeter was compared between the edematous eye and the nonedematous fellow eye of each patient and between groups. The macular thickness was evaluated with optical coherence tomography. Results: The mean macular blood flow was significantly higher than that of the contralateral eyes in edematous eyes of non-ERM-DME group (798.8 vs. 379.8 AU, p < 0.001). By contrast, in the ERM-DME group, the mean macular blood flow of DME eyes was similar to that of fellow eyes (575.9 vs. 596.4 AU, p = 0.538). The macular capillary blood flow in patients with BVO was not significantly different compared with nondiabetic controls (p = 0.967). Conclusions: The results suggest that the alteration of macular microcirculation may play a role in the pathogenesis of diffuse DME without vitreomacular traction.
Characterization of the Projections to the Hypothalamic Paraventricular and Periventricular Nuclei in the Female Sheep Brain, Using Retrograde Tracing and Immunohistochemistry
Authors: Qi Yue , Namavar M.R. , Iqbal J. , Oldfield B.J. , Clarke I.J.
Published: May 2009

The paraventricular nucleus (PVN) and the periventricular nucleus (Pe) are important neuroendocrine centers, but the neuronal input to these regions is poorly defined in nonrodent species. We utilized the retrograde transport of injected tracers to determine the neural input to these two nuclei in the ovine brain. Adult Corriedale ewes were studied following FluoroGold injection into either the PVN (n = 5) or the Pe (n = 3). Both the PVN and the Pe were found to receive neuronal input from a number of hypothalamic nuclei. Projections to the PVN from the lateral hypothalamic area were from neurons that produce melanin-concentrating hormone or orexins and a subset of those from the arcuate nucleus were immunopositive for neuropeptide Y and γ-melanocyte stimulating hormone. This pathway was verified by staining of terminals in the PVN. Input to the PVN from the brain stem was seen to originate from the catecholaminergic and serotoninergic neurons. The projections to the PVN and Pe from hypothalamic and brain stem regions in the sheep brain are generally similar to those in the rat, with some minor differences. These studies highlight the differences in the afferent input to these two closely related nuclei in the ovine brain.
Effects of Lipoxin A4 on CoCl2-Induced Angiogenesis and Its Possible Mechanisms in Human Umbilical Vein Endothelial Cells
Authors: Liu Songjun , Wu Ping , Ye Duyun , Huang Yinping , Zhou Xiaoyan , Li Yongsheng , Cai Lei
Published: May 2009

Lipoxin A4 (LXA4), a ‘stop signal’ for inflammation, is endogenously produced by eicosanoids, mainly via cell-to-cell interactions. At present, its influence on hypoxic angiogenesis, which is responsible for tumor growth and metastasis, has not been determined. Hypoxia regulates a variety of transcription factors including hypoxia-inducible factor (HIF)-1α, which plays a role in the expression of vascular endothelial growth factor (VEGF) and is considered a target for anti-angiogenic therapy. In this study, we utilized cobalt chloride (CoCl2) to mimic hypoxia in vitro. Data suggested that LXA4 decreased the expression and nucleus translocation of HIF-1α in a dose-dependent manner in CoCl2-treated human umbilical vein endothelial cells (HUVEC). Furthermore, we confirmed that LXA4 suppressed VEGF expression, tube formation and migration activity of HUVEC under hypoxia induced by CoCl2. These results suggest that LXA4 may have inhibitory effects on tumor angiogenesis through downregulation of the expression and nucleus translocation of HIF-1α. In summary, this study provides the first evidence for the anti-angiogenic role of LXA4 on hypoxic human endothelial cells, which may have therapeutic value for cancer and other angiogenesis-associated diseases.
Die Reaktionen kritisch kranker Patienten unter Volumentherapie mit Hydroxyäthylstärke (6%HES 450/0,7)
Authors: McCartney S.F. , Appel P.L. , Shoemaker W.C. , Beez M.G.
Published: May 2009

Bei 31 kritisch kranken chirurgischen Patienten wurden hämodynamische und (O2-Transport-Variable nach klinisch erforderlicher Volumentherapie mit 500ml 6% HES 450/0,7 bestimmt. Es ergaben sich signifikante Maximal-Anstiege des Herzindex (CI) von 3,5 ± 2,1 auf 4,4 ± 0,2 (1/min/m2) und des Wedge-Drucks von 9,3 ± 0,7 auf 13,6 ± 0,8 (mmHg) und eine signifikante Verminderung des systemischen Widerstands (SVRI) von 2018 ± 128 auf 1641 ± 102 (dynsec/cm5 m2). Auβerdem wurden maximale Anstiege der linksventrikulären Schlagarbeit (LVSWI) von 41 ± 3,1 auf 53 ± 3,2 (gm/m2), der Sauerstoffver-fügbarkeit (DO2) von 489 ± 24 auf 587 ± 29 (ml/min/m2) und des Sauerstoffverbrauchs (VO2) von Ill ± 6 auf 130 ± 7 (ml/min/m2) während der maximalen Herzindex-Steigerung beobachtet. Darüber hinaus wurden die Reaktionen der Patienten (MAP, CI, VO2) nach verschiedenen klinischen Gesichtspunkten wie OP-Zeitpunkt, Alter, Prognose, ARDS, Sepsis, Hyperdynamik und Blutvolumen aufgeschlüsselt.
Malnutrition and Metabolic Abnormalities in Cancer Patients
Authors: Daly J.M.
Published: May 2009

Malnutrition is a common problem in cancer patients. The most clear-cut cause is anorexia and a decrease in food intake. Other causes include alterations in carbohydrate, fat and protein metabolism which result in losses of energy and amino acids from the host. Understanding the pathophysiology of these changes will provide avenues to better nourish cancer patients and improve their quality of life.
Merkmale und Mechanismen der Tumoranorexie
Authors: Lehnert H.
Published: May 2009

Bei der Tumor-Anorexie handelt es sich um eine kontinuierliche Reduktion der Nahrungszufuhr bei erhöhtem Energiebedarf des Organismus. Als Grundlagen und mögliche Ursachen dieser negativen Energiebilanz während des Krankheitsprozesses werden insbesondere metabolische Störungen, Änderungen der Geschmackswahrnehmung, neuroendokrine Prozesse und Verhaltens-psychologische Bedingungen diskutiert. Ein einheitliches Entstehungsmodell existiert nicht, so daβ sich derzeit nur adjuvante Therpiemöglichkeiten ergeben.
Carbohydrate Metabolism in Neoplastic Tissue
Authors: Eigenbrodt E. , Reinacher M.
Published: May 2009

The kinetic and immunological properties of purified, homogeneous pyruvate kinase type M2 from chicken lung and tumors, including that of Rous sarcoma virus transformed chicken fibroblasts, have been compared. The type M2 enzymes from both lung and tumors have immunologically distinct structures. The enzyme isolated from tumors is characterized by a low affinity for phosphoenol pyruvate, pronounced L-serine activation and a strong inhibition by L-alanine, L-proline and several other amino acids. The chicken lung enzyme is only slightly affected by serine. The cellular amino acid concentration is in such a range that the tumor enzyme is strongly inhibited whereas the lung enzyme is only partially inhibited. The characteristics of the tumor enzyme allow the optimal adaptation to lactic acid and production of energy from glucose or amino acids dependent on substrate and oxygen supply.
Adjuvante parenterale Ernährung bei chemo- und radiotherapeutischen Maßnahmen in der Hämatologie
Authors: Grünert A. , Heim F.
Published: May 2009

Die Studie widmet sich der klinischen Ernährungstherapie onkologischer Patienten als einer wesentlichen adjuvanten Maßnahme in der Gesamttherapie. Gegenstand der Studie war die Übertragung von ernährungstherapeutischen Konzepten aus dem Nichtmalignombereich auf onkologische Patienten. Wir untersuchten die biochemischen und biophysikalischen Kenngrößen der Homöostase sowohl im Blut als auch im Urin anhand der Osmolalität, Natrium, Kalium, Gesamteiweiß, Albumin, Triglyzeride, Fettsäuren, Glukose, Laktat, Aminosäuren sowie Harnstoff und Kreatinin. Als Kenngrößen im Urin wurden neben dem Ausscheidungsvolumen die Osmolalität, Natrium, Kalium, Kreatinin, Harnstoff, Gesamtstickstoff und die Aminosäuren gemessen. Ein besonderes Augenmerk in der Studie lag auf der Stickstoffhomöostase, die mit Hilfe der Stickstoffverluste und der Stickstoffbilanz beschrieben wird. Bei 10 Patienten, die entweder an einer transplantationsgeeigneten Panmyelopathie oder an einer Leukämie litten, wurden die Untersuchungen durchgeführt, wobei auch die immunsuppressorische Vorbereitungsphase mit Ganzkörperbestrahlung und zytostatische Therapie miteinbezogen war. Die parenterale Ernährung wurde mit Aminosäuren (1 g/kg/d), Kohlenhydraten (6,5 g/kg/d), Triglyzeriden (1 g/kg/d) durchgeführt. Die Ernährungstherapie wurde nur an den beiden der aggressiven immunsuppressiven Therapie folgenden Tage unterbrochen, da an diesen Tagen zur Erzielung einer nephroprotektiven Polyurie die Flüssigkeitszufuhr auf etwa 6 1 Elektrolytlösung/24 h eingerichtet werden mußte. Die Untersuchungsdauer erstreckte sich über die gesamte Therapiedauer, die bei einigen Patienten bis zu 3 Monaten anhielt. Ein wesentliches Ergebnis ist die Erzielbarkeit der Konstanz des Körpergewichts, welches unter der konventionellen Therapie ohne optimierte Ernährung kräftige Reduktionen aufwies. Wesentliches Ergebnis ist auch, daß sich hinter den meist im physiologischen Referenzbereich liegenden Medianwerten erhebliche interindividuelle Schwankungen verbergen, die unterstreichen, daß die individuelle Vermessung und Überwachung der Patienten unverzichtbar ist. Die Stickstoffbilanz wie die Stickstoffausscheidung zeigen den im Anschluß an die immunsuppressive Behandlung auftretenden enormen Verlust von etwa 20 g Stickstoff in 24 h. Als Schlußfolgerung ergibt sich die Übertragbarkeit der bei Nicht-malignompatienten entwickelten Ernährungstherapie auf die onkologischen Patienten. Dabei wird nicht nur eine weitgehende Vermeidung des Verlustes an körpereigener Substanz in den hoch katabolen Zuständen bewirkt, sondern darüber hinaus die Akzeptanz der Knochenmarktransplantation drastisch erhöht.
Klinische Untersuchung zur bakteriellen Kontamination zweier verschieden zubereiteter enteraler Nährlösungen
Authors: Pfenninger E. , Grünert A. , John U. , Wiedeck H.
Published: May 2009

Zwei enterale Nährlösungen, die Oligopeptiddiät Peptisorb® und die Nährstoff-definierte Diät Biosorb® wurden unter den Bedingungen einer Intensivstation auf ihre bakterielle Kontamination untersucht. In der Oligopeptiddiät, die in Pulverform vorliegt und vor Applikation erst zubereitet werden muβ, lieβ sich nach der Zubereitung ein Keimwachstum in 54% der untersuchten Proben nachweisen, der Prozentsatz stieg bis zum Ende der 6- bzw. 12stündigen Applikations-periode auf 79 % an. Die steril gelieferte, fertig zubereitete nährstoff-definierte Diät war in 97% der Fälle vor Verabreichung keimfrei, am Ende der Applikationsperiode waren nur 21 % der Proben kontaminiert. Die auf der Intensivstation aufbereiteten Lösungen wiesen vorwiegend grampositive Sporenbildner und gramnegative, als Hospitalismuskeime bekannte Erreger auf. Um enterale Nährlösungen als mögliche Kontaminationsquelle von Intensivpatienten zu vermeiden, sollten unseren Untersuchungen zufolge, wenn immer nur möglich, schon applikationsgerecht zubereitete, steril vom Hersteller gelieferte Nährlösungen Verwendung finden.
Muscle Biopsy Studies on Protein-Energy Malnutrition in Patients with Chronic Relapsing Pancreatitis
Authors: Guarnieri G. , Toigo G. , Situlin R. , Crapesi L. , Del Bianco M.A. , Zanettovich A. , Mandero E. , Resetta G.
Published: May 2009

Malnutrition is a common finding in chronic pancreatitis and its pathogenesis is multifactorial. In 14 patients with chronic pancreatitis we assessed the dietary intake, some anthropometric indices and the concentration of some serum proteins. In muscle specimens obtained by needle biopsy we examined the DNA, RNA and non-collagen alkali-soluble protein (ASP) content. In muscle we determined also the activity of cathepsin D, an enzyme involved in intracellular myofibrillar catabolism. Protein and energy intake were lower than in the normal healthy population. Plasma protein content (an index of liver protein synthesis) was generally in the normal range, whereas anthropometry and the biochemical muscle indices were generally subnormal, suggesting a depressed muscle protein content and synthesis (evaluated, respectively, by the ASP: DNA and RNA: DNA ratios). Cathepsin D activity was lower than in controls, and the percentage of ‘free’ activity tended to be higher but not significantly. This study suggests that muscle protein content and synthesis are reduced in patients with chronic pancreatitis, whereas liver protein synthesis is generally preserved. Possibly as a consequence of metabolic abnormalities and/or of an inadequate protein and energy intake, the nutritional status was often abnormal in our patients and a nutritional support therapy was needed.
Metabolic Changes of Patients with Acute Necrotizing Pancreatitis
Authors: Roth E. , Zöch G. , Mauritz W. , Karner J. , Funovics J. , Sporn P. , Fritsch A.
Published: May 2009

We carried out metabolic investigations of 26 patients with severe forms of acute pancreatitis which were evaluated by an organ score. We formed six groups from this data: survivors and deceased in the first week, the second week, and after a further two weeks of illness. The amino acid patterns in plasma and muscles deviated considerably from normal at all times in both the surviving and the deceased patients. In particular, changes in the concentrations of branched-chain amino acids and glutamine in the muscle tissue have a prognostic value. In the range two to four (normal range: above 20), the factor glutamine VAL + LEU + ILE characterizes a prefinal condition in non-survivors. This factor increased in patients recovering from the illness from 6 to values over 20. Non-survivors (NS) had higher plasma levels of glucose and glucagon compared to surviving patients. Plasma glucagon concentrations in NS reached levels up to 4,000 pg/mL at admission, which declined gradually to normal range during the course of the illness.
Ammoniak- und Glutaminstoffwechsel des Darms
Authors: Soeters P.B. , van Leeuwen P.A.M.
Published: May 2009

Die Untersuchungen beschäftigen sich mit den Fragen, wieviel Ammoniak durch die Darmmukosa und wieviel durch die Darmflora produziert wird, und wie Neomyzin und Laktulose diese Prozesse beeinflussen. Untersuchungen am Rattendarm in vitro zeigen, daβ Mukosazellen bei Inkubation mit Glutamin Ammoniak, Alanin und Glutaminsäure produzieren. Diese Produktion kann durch Laktulose oder Neomyzin reduziert werden. Da Zellen keimfreier Ratten diese Stoffe in gleicher Menge produzieren, kann der Einfluβ der Bakterien unter den gewählten Bedingungen nicht groβ sein. Zwischen Zellen der Krypten und der Villi bestehen keine Unterschiede. Zur Feststellung des Beitrags der Flora an der Ammoniakproduktion im Darm wird diese durch verschiedene Antibiotika manipuliert, und Ammoniakspiegel werden im Portalblut gemessen. Nach Elimination der aeroben Flora tritt nur eine geringe Senkung des Ammoniakspiegels auf, während die Ausschaltung der anaeroben Flora eine extreme Reduzierung der Ammoniakbildung zur Folge hat. Kolonisation keimfreier Ratten mit aeroben Bakterien hat keinen Einfluβ, während Kolonisation mit anaeroben Bakterien zu einer Steigerung des portalen Ammoniakgehalts führt, die jedoch nicht die Werte konventioneller Tiere erreicht. Untersuchungen mit Laktulose und Neomyzin zeigen, daβ die Erniedrigung der Ammoniakproduktion nicht durch Veränderungen der Keimzahlen erklärt werden kann. Laktulose und Neomyzin beeinflussen die Ammoniakbildung im Darm durch Interferenz mit der Aufnahme von Glutamin in die Mukosazellen und dessen weiterem Stoffwechsel, Die möglichen Ursachen für die starke Zunahme der arteriellen Glutaminspiegel in konventionellen Ratten werden diskutiert.
Der Einfluß von L-Carnitin auf den Postaggressionsstoffwechsel operierter Patienten
Authors: Heller W. , Musil HE. , Gaebel G. , Hempel V. , Krug W. , Köhn HJ.
Published: May 2009

Es sollte geprüft werden, inwieweit die Verabreichung von L-Carnitin den Postaggressionsstoffwechsel günstig beeinflussen kann. Die klinischen Untersuchungen erfolgten an 3 Patientenkollektiven (K1, K2 und K3), die sich chirurgischen Eingriffen von etwa gleicher Größen-ordnung wie Magen- und Darmresektionen unterziehen mußten und während der ersten 3 postoperativen Tage ein parenterales, standardisiertes hypokalorisches Ernährungsregime ohne Carnitin (K1) und mit Carnitin (K2: 2g und K3: 4g) erhielten. Beurteilungsparameter für den Carnitineffekt waren: freie Fettsäuren (FFS), Triglyzeride (TG), β-Hydroxybuttersäure (β-OH-BS), Azetazetat (ACAC), Blutzucker (BZ), Insulin (INS), Laktat (LAK), Pyruvat (PYR), Gesamteiweiß (GE), Cholinesterase (CHE), Harnstoffproduktionsrate (PU), α-Aminostickstöff (α-AN), Stickstoffbilanz (NB), Katabolieindex (KI), BUN-Kreatinin-Quotient (B/K), Gesamtcarnitin (GC), freies Carnitin (FC), Azetylcarnitin (AC) sowie die Relation Azetylcarnitin zu freiem Carnitin (AC/FC) im Serum und Harn. Die Ergebnisse zeigten keine statistische Signifikanz, erlauben jedoch trendorientierte Rückschlüsse. Demnach vermindert Carnitin offenbar die Insulinresistenz, nicht aber die postoperative Glukoseverwertungsstörung forciert Carnitin die Verbrennung langkettiger Fettsäuren und verbessert dadurch den Energieumsatz, führt Carnitin zu einer etwas früher einsetzenden positiven Stickstoffbilanz, ermöglicht eine Carnitinsubstitution von täglich 4 g bereits nach 3 Tagen eine Repletion der Gewebedepots und besteht eine Dosisabhängigkeit für Carnitin bei Verbrennung langkettiger Fettsäuren und Wiederauffüllung der Gewebespeicher.