bluuebunny/crossref_metadata_2025 huggingface dataset:
Review: new biological insights in early clinical studies
Authors: Maur Michela , Sessa Cristiana
Published: March 2007

First in human phase I trials are an unaviodable gateway to the development of new anticancer therapies. The discovery of target therapies have significantly changed the process of clinical drug development.

This short review will focus on the main features including knowledge of biological aspects, methodology and adequacy of design and of performance of early clinical studies. Copyright © 2007 John Wiley & Sons, Ltd.
Doxorubicin cardiomyopathy via TLR‐2 stimulation: potential for prevention using current anti‐retroviral inhibitors such as ritonavir and nelfinavir
Authors: Kast R. E. , Foley K. F. , Focosi D.
Published: March 2007

Doxorubicin remains a useful anti‐cancer drug but as lifetime dose approaches 500 mg/m2 and particularly when this dose is exceeded, iatrogenic life‐threatening cardiomyopathy becomes progressively more likely. This note reviews evidence indicating that doxorubicin induced cardiomyopathy is partly mediated by stimulation of Toll‐like receptors (TLR) 2 and 4 which are expressed on cardiomyocytes. Indinavir, nelfinavir, ritonavir, and saquinavir are currently marketed protease inhibitors used to suppress human immunodeficiency virus. They have recently been shown to inhibit signalling at TLR 2 and 4 as well as intracellular events downstream from these receptors. It is possible that these FDA‐approved anti‐retroviral protease inhibitors could be used off‐label to diminish likelihood of doxorubicin cardiotoxicity permitting higher doxorubicin doses. We suggest that currently marketed anti‐viral protease inhibitors be investigated in animal models of doxorubicin cardiomyopathy and if such studies do indeed show protection, human studies be initiated. Copyright © 2007 John Wiley & Sons, Ltd.
Involvement of PPARγ and E‐cadherin/β‐catenin pathway in the antiproliferative effect of conjugated linoleic acid in MCF‐7 cells
Authors: Bocca Claudia , Bozzo Francesca , Francica Simona , Colombatto Sebastiano , Miglietta Antonella
Published: March 2007

Conjugated linoleic acid (CLA) is a naturally occurring fatty acid, which has been shown to exert beneficial effects against breast carcinogenesis. It has been reported that CLA could modulate cellular proliferation and differentiation through the activation of peroxisome proliferator‐activated receptors (PPARs). Among different PPAR isotypes, PPARγ is involved in growth inhibition of transformed cells. Ligands of PPARγ are considered as potential anticancer drugs, so CLA was tested for its ability to induce PPARγ expression in MCF‐7 breast cancer cells. The effects of CLA and of a specific synthetic PPARγ antagonist were evaluated on cell growth as well as on parameters responsible for cell growth regulation. We demonstrated here that CLA stimulated the expression of PPARγ to levels up to control and caused PPARγ translocation into the nucleus. Furthermore, the overexpression of PPARγ positively correlates with the inhibition of cell proliferation and with the modulation of ERK signaling induced by CLA; in all cases the administration of the antagonist reverted CLA effects. The PPAR‐signaling pathway is connected with the β‐catenin/E‐cadherin pathway, thus we evaluated CLA effects on the expression and cellular distribution of these proteins, which are involved in cell adhesion and responsible for invasive behavior. The treatment with CLA determined the up‐regulation and the redistribution of β‐catenin and E‐cadherin and the antagonist reverted only the effect on β‐catenin. These studies indicate that CLA regulates PPARγ expression by selectively acting as an agonist and may influence cell–cell adhesion and invasiveness of MCF‐7 cells. © 2007 Wiley‐Liss, Inc.
Expression of NF‐κB parallels COX‐2 expression in oral precancer and cancer: Association with smokeless tobacco
Authors: Sawhney Meenakshi , Rohatgi Nidhi , Kaur Jatinder , Shishodia Shishir , Sethi Gautam , Gupta Siddhartha D. , Deo Suryanaryana V. S. , Shukla Nootan K. , Aggarwal Bharat B. , Ralhan Ranju
Published: March 2007

Nuclear Factor‐κB (NF‐κB) activation and COX‐2 overexpression have been reported in head and neck cancer, but the relationship between these proteins remains to be investigated. To determine the relationship between NF‐κB and COX‐2 in Smokeless Tobacco (ST) associated oral tumorigenesis, we performed immunohistochemistry in serial sections from 107 OSCCs, 78 oral precancerous lesions (OPLs) (58 hyperplasias, 20 dysplasias) and 15 histologically normal oral tissues and correlated with clinicopathological data. Significant increase in NF‐κB and COX‐2 immunopositivity was observed from normal oral mucosa to OPLs to OSCCs (p = 0.009 and p = 0.002 respectively). Upregulation of NF‐κB and COX‐2 was observed as early as in hyperplasia [p = 0.006; OR = 6.1 and p = 0.003; OR = 7.6, respectively]. Expression of both proteins was found to be significantly associated in OPLs (p = 0.000; OR = 12.6) and OSCCs (p = 0.001; OR = 4.0). Intriguingly, khaini consumption correlated with NF‐κB immunopositivity in OPLs (p = 0.05, OR = 3.8) and OSCCs (p = 0.01, OR = 3.4) and with COX‐2 expression in OPLs (p = 0.03; OR = 4.3). In vitro experimental system of ST associated oral carcinogenesis was used to demonstrate ST (khaini) and NNK mediated activation of NF‐κB and COX‐2, supporting the clinical data. In conclusion, this study demonstrates correlation between over expression of NF‐κB and COX‐2 in early precancerous stages of development of oral cancer and sustained elevation down the tumorigenic pathway, underscoring their potential as targets for early intervention. In vitro studies demonstrated that NNK may be one of the carcinogenic components of ST (khaini) inducing activation of NF‐κB and COX‐2 in oral precancer and cancer cells, suggesting plausible role in ST‐induced oral carcinogenesis. © 2007 Wiley‐Liss, Inc.
Decreased intraperitoneal disease recurrence in epithelial ovarian cancer patients receiving intraperitoneal consolidation treatment with yttrium‐90‐labeled murine HMFG1 without improvement in overall survival
Authors: Oei Angèle L. , Verheijen René H. , Seiden Michael V. , Benigno Benedict B. , Lopes Alberto , Soper John T. , Epenetos Agamemnon A. , Massuger Leon F.
Published: March 2007

This study analyzes the site of disease recurrence in ovarian cancer patients to assess the influence of a single intraperitoneal (IP) administration of yttrium‐90‐labeled murine monoclonal antibody HMFG1 (90Y‐muHMFG1) on the pattern of disease recurrence. In a large phase III trial ovarian cancer patients in complete clinical remission with FIGO stage Ic‐IV were randomized between standard treatment plus a single IP 90Y‐labeled muHMFG1 versus standard treatment alone after negative second‐look laparoscopy. Case report forms of all patients with disease recurrence were reviewed to determine site and date of recurrent disease. In total 447 patients were included in the study with a median follow‐up of 3.5 years. Relapse was seen in 104/224 in the active and 98/223 in the control arm. Significantly fewer IP (p < 0.05) and more extraperitoneal (p < 0.05) relapses occurred in the active treatment arm. Time to IP recurrence was significantly longer (p = 0.0019) and time to extraperitoneal recurrence was significantly shorter for the active treatment arm (p < 0.001). The impact of IP radioimmunotherapy on IP relapse‐free survival could only be seen in the subgroup of patients with residual disease after primary surgery (HR, 0.31; 95% CI, 0.18 to 0.53; p = 0.002). Although, there is no survival benefit for IP radioimmunotherapy as consolidation treatment for epithelial ovarian cancer, we found an improved control of IP disease, that was offset by increased extraperitoneal recurrences. © 2007 Wiley‐Liss, Inc.
Meat and meat‐mutagen intake, doneness preference and the risk of colorectal polyps: The Tennessee colorectal polyp study
Authors: Shin Aesun , Shrubsole Martha J. , Ness Reid M. , Wu Huiyun , Sinha Rashmi , Smalley Walter E. , Shyr Yu , Zheng Wei
Published: March 2007

Although meat intake has been fairly consistently linked to the risk of colorectal cancer, only a few studies have evaluated meat intake by doneness level and the heterocyclic amines (HCAs) and polycyclic aromatic hydrocarbons (PAHs) produced by high temperature cooking of meat in relation to colorectal adenomatous and hyperplastic polyps. We evaluated these associations in a large colonoscopy‐based case‐control study. Included in this study were participants with adenomatous polyp only (n = 573), hyperplastic polyp only (n = 256), or both adenomatous and hyperplastic polyps (n = 199), and 1,544 polyp‐free controls. In addition to information related to demographic and other lifestyle factors, meat intake by cooking method and doneness preference were obtained through telephone interviews. Polytomous logistic regression models were used to estimate odds ratios (OR) and 95% confidence intervals for the association between exposures and colorectal polyp risks. Presence of hyperplastic polyp was found to be positively associated with high consumption of total meat (ptrend = 0.076) or red meat (ptrend = 0.060), with an approximate 50–60% elevated risk observed in the highest vs. the lowest intake group. High intake of 2‐amino‐I‐methyl‐6‐phenylimidazo[4,5‐b]pyridine (PhIP) and 2‐amino‐3,4,8‐trimethylimidazo [4,5]quinoxaline (DiMeIQx) were associated with increased risk for hyperplastic polyp (ptrend = 0.036 and 0.038, respectively). With a possible exception of the intake of total well‐done meats (ptrend = 0.055) or well‐done red meats (ptrend = 0.074) with the risk of large adenomas, no other positive association was found specifically for the risk of adenomas with any of the exposure variables aforementioned. This study provides additional support for a positive association of high intake of red meat with colorectal adenomas, and suggests that high intake of meats and meat carcinogens may also be associated with hyperplastic polyps. © 2007 Wiley‐Liss, Inc.
Aberrant regulation of argininosuccinate synthetase by TNF‐α in human epithelial ovarian cancer
Authors: Szlosarek Peter W. , Grimshaw Matthew J. , Wilbanks George D. , Hagemann Thorsten , Wilson Julia L. , Burke Frances , Stamp Gordon , Balkwill Frances R.
Published: March 2007

The pro‐inflammatory cytokine, tumour necrosis factor‐α, TNF‐α, is dysregulated in malignant compared with normal ovarian surface epithelium (OSE). Several epidemiological studies have associated inflammation with ovarian tumorigenesis, with TNF‐α playing a key role in modulating invasion, angiogenesis and metastasis. Here, we show that TNF‐α also induces expression of arate‐limiting enzyme in arginine synthesis, argininosuccinate synthetase (AS), thereby linking inflammation with several arginine‐dependent metabolic pathways, implicated in accelerated carcinogenesis and tumour progression. Having identified AS mRNA induction in TNF‐α‐treated IGROV‐1 ovarian cancer cells, using RNA‐arbitrarily primed‐PCR, we then observed differential regulation of AS mRNA and protein in malignant, compared with normal, OSE cells. A cDNA cancer profiling array with matched normal ovarian and ovarian tumour samples revealed increased expression of AS mRNA in the latter. Moreover, AS protein co‐localised with TNF‐α in ovarian cancer cells, with significantly higher levels of AS in malignant compared with normal ovarian tissue. Increased co‐expression of AS and TNF‐α mRNA was also observed in 2 other epithelial tumours, non‐small cell lung and stomach cancer, compared with normal corresponding tissues. In summary, high levels of AS expression, which may be required for several arginine‐dependent processes in cancer, including the production of nitric oxide, proline, pyrimidines and polyamines, is regulated by TNF‐α and may provide an important molecular pathway linking inflammation and metabolism to ovarian tumorigenesis. © 2007 Wiley‐Liss, Inc.
Finite sample evidence of IV estimators under weak instruments
Authors: Flores‐Lagunes Alfonso
Published: March 2007

We present finite sample evidence on different IV estimators available for linear models under weak instruments; explore the application of the bootstrap as a bias reduction technique to attenuate their finite sample bias; and employ three empirical applications to illustrate and provide insights into the relative performance of the estimators in practice. Our evidence indicates that the random‐effects quasi‐maximum likelihood estimator outperforms alternative estimators in terms of median point estimates and coverage rates, followed by the bootstrap bias‐corrected version of LIML and LIML. However, our results also confirm the difficulty of obtaining reliable point estimates in models with weak identification and moderate‐size samples. Copyright © 2007 John Wiley & Sons, Ltd.
Robust optimal monetary policy in a forward‐looking model with parameter and shock uncertainty
Authors: Giannoni Marc P.
Published: March 2007

This paper characterizes a robust optimal policy rule in a simple forward‐looking model, when the policymaker faces uncertainty about model parameters and shock processes. We show that the robust optimal policy rule is likely to involve a stronger response of the interest rate to fluctuations in inflation and the output gap than is the case in the absence of uncertainty. Thus parameter uncertainty alone does not necessarily justify a small response of monetary policy to perturbations. However, uncertainty may amplify the degree of ‘super‐inertia’ required by optimal monetary policy. We finally discuss the sensitivity of the results to alternative assumptions. Copyright © 2007 John Wiley & Sons, Ltd.
Phlegmasia cerulea dolens
Authors: Bhatt Shweta , Wehbe Charles , Dogra Vikram S.
Published: March 2007

Phlegmasia dolens is a rare form of massive venous thrombosis of the lower extremities that is associated with a high degree of morbidity, including venous gangrene, compartment type syndrome, and arterial compromise. We report the sonographic findings in a patient who presented with phlegmasia dolens. © 2007 Wiley Periodicals, Inc. J Clin Ultrasound, 2007
Preoperative localization of parathyroid adenoma with sonography and 99mTc‐sestamibi scintigraphy in primary hyperparathyroidism
Authors: Grosso Ilaria , Sargiotto Antonella , D'Amelio Patrizia , Tamone Cristina , Gasparri Guido , De Filippi Pier Giuseppe , Picciotto Giuseppe , Isaia Giancarlo
Published: March 2007

Purpose. To evaluate the sensitivity, specificity, and usefulness of dual‐phase 99mTc‐Sestamibi scintigraphy (SS) and sonography (US) of the neck, alone and in combination, as noninvasive adenoma localizing procedures in patients with primary hyperparathyroidism prior to parathyroidectomy.

Methods. We retrospectively analyzed the charts of 79 patients with parathyroid (PT) adenomas and confirmed diagnosis of hyperparathyroidism who were evaluated with SS and US prior to successful parathyroidectomy.

Results. Ninety‐three adenomas were removed during bilateral neck exploration. SS alone showed a sensitivity of 76% and a specificity of 79% compared with 89% and 75%, respectively, for US performed after SS on the same day. Combination of the 2 procedures yielded a sensitivity of 89% and a specificity of 90%, with 22% discordant results. The differences in sensitivity and specificity between the 2 techniques alone or in combination were not statistically significant.

Conclusions. No benefit was gained from using both SS and US for the preoperative localization of PT adenomas in patients with primary hyperparathyroidism. Each technique can be negatively affected by thyroid enlargment and nodularity. US, when performed by a skilled operator, is a reliable tool for PT adenoma localization. If the US findings are inconclusive, SS should be used. © 2007 Wiley Periodicals, Inc. J Clin Ultrasound, 2007
siRNA delivery by a transferrin‐associated lipid‐based vector: a non‐viral strategy to mediate gene silencing
Authors: Cardoso A. L. C. , Simões S. , de Almeida L. P. , Pelisek J. , Culmsee C. , Wagner E. , Pedroso de Lima M. C.
Published: March 2007

Background

RNA interference provides a powerful technology for specific gene silencing. Therapeutic applications of small interfering RNA (siRNA) however require efficient vehicles for stable complexation, protection, and extra‐ and intracellular delivery of these nucleic acids. Here, we evaluated the potential of transferrin (Tf)‐associated liposomes for siRNA complexation and gene silencing.

Methods

Cationic liposomes composed of DOTAP : Cholesterol associated with or without transferrin (Tf) were complexed with siRNA at different lipid/siRNA charge ratios. Complexation and protection of siRNA from enzymatic degradation was assessed with the PicoGreen intercalation assay and gel electrophoresis. Cellular internalization of these siRNA Tf‐lipoplexes was detected by confocal microscopy. Luciferase assay, immunoblot and fluorescence‐activated cell sorting (FACS) analysis were used to evaluate reporter gene silencing in Huh‐7 hepatocarcinoma and U‐373 glioma cells. c‐Jun knockdown in HT‐22 cells was evaluated by quantitative real‐time polymerase chain reaction (RT‐PCR). Cytotoxicity of the siRNA complexes was assessed by Alamar blue, lactate dehydrogenase and MTT assays.

Results

Complexation of siRNA with the cationic liposomes in the presence of Tf results in the formation of stable particles and prevents serum‐mediated degradation. Confocal microscopy showed fast cellular internalization of the Tf‐lipoplexes via endocytosis. In the GFP glioma cells Tf‐lipoplexes showed enhanced gene silencing at minimum toxicity in comparison to Tf‐free lipoplexes. Targeting luciferase in the hepatocarcinoma cell line resulted in more than 70% reduction of luciferase activity, while in HT‐22 cells 50% knockdown of endogenous c‐Jun resulted in a significant protection from glutamate‐mediated toxicity.

Conclusions

Cationic liposomes associated with Tf form stable siRNA lipoplexes with reduced toxicity and enhanced specific gene knockdown activity compared to conventional lipoplexes. Thus, such formulations may constitute efficient delivery systems for therapeutic siRNA applications. Copyright © 2007 John Wiley & Sons, Ltd.
Identification of transfected cell types following non‐viral gene transfer to the murine lung
Authors: Davies Lee A. , Seguela Claire , Varathalingam Anusha , Cheng Seng H. , Hyde Stephen C. , Gill Deborah R.
Published: March 2007

Background

Identification of the cell types transfected following gene transfer is an important factor in the selection of appropriate gene transfer agents (GTAs). Due to the relatively low gene expression mediated by non‐viral GTAs, current methodologies for the detection and identification of transfected cells in the lung have proven insensitive and unreliable. We have investigated the use of the green fluorescent protein (GFP) to identify transfected cells in a mouse lung model.

Methods

Direct visualisation of GFP fluorescence in frozen histological sections was used in conjunction with a panel of cell type specific antibodies to investigate the distribution and level of gene expression in mouse lungs following instillation of non‐viral GTAs.

Results

Despite considerable tissue autofluorescence, dose‐dependent expression of GFP was detected following instillation of as little as 25 µg naked plasmid DNA (pDNA). Naked pDNA and pDNA complexed with polyethylenimine appeared to transfect mainly ciliated cells and Clara cells of the conducting airway, whereas expression mediated by pDNA complexed with the cationic lipid GL67 was found predominantly in type I pneumocytes.

Conclusions

Direct visualisation of GFP expression was used to detect transfected cell types in the mouse lung. In contrast with observations made using ß‐galactosidase as a reporter, gene expression from several non‐viral GTAs was readily demonstrated and no false GFP‐positive cells were ever detected in untreated lung tissues. Lung delivery of different GTAs resulted in GFP expression in different cell types, confirming the importance of identification of transfected cells when screening and selecting GTAs for disease targets. Copyright © 2007 John Wiley & Sons, Ltd.
Fiber‐knob modifications enhance adenoviral tropism and gene transfer in malignant glioma
Authors: Zheng Sophy , Ulasov Ilya V. , Han Yu , Tyler Matthew A. , Zhu Zeng B. , Lesniak Maciej S.
Published: March 2007

Background

Malignant gliomas remain refractory to Ad5‐mediated gene therapy due to deficiency of the coxsackie adenovirus receptor on tumor cells. The purpose of this study was to evaluate whether changes in adenoviral tropism can enhance gene transfer in the context of malignant glioma.

Methods

We have identified several receptors that are over‐expressed on tumor cells and created a series of pseudotyped Ad5 vectors that recognize these receptors: Ad5‐RGD which binds αvβ3/αvβ5 integrins; Ad5/3 which contains adenovirus serotype 3 knob and binds to CD46; Ad5‐Sigma which incorporates the reovirus sigma knob and binds to junctional adhesion molecule‐1; and Ad5‐pk7 which contains the polylysine motif and binds heparan sulfate proteoglycans. We also investigated the Ad5‐CAV1 vector, which contains the knob of canine adenovirus type 1, a virus previously shown to infect glioma via an unknown mechanism. In this study, we compared these modified vectors for their ability to promote the expression of luciferase transgene both in vitro and in vivo.

Results

Our results indicate that all five modified vectors attained higher mean luciferase activity vs. control. Among them, Ad5‐CAV1 and Ad5‐pk7 attained the highest transduction efficiency independent of different tumor lines or infection time. Ad5‐Sigma and Ad5‐pk7 also demonstrated the least nonspecific infection in normal human astrocytes. Most importantly, Ad5‐pk7 achieved 1000‐fold increased transgene expression in human glioma xenografts in vivo.

Conclusions

These results indicate that modifications of adenoviral tropism can enhance gene transfer in tumors that are poorly susceptible to adenoviral vectors and warrant further development of Ad5‐pk7 for glioma gene therapy. Copyright © 2007 John Wiley & Sons, Ltd.
Modified synthetic siRNA targeting tissue inhibitor of metalloproteinase‐2 inhibits hepatic fibrogenesis in rats
Authors: Hu Ying‐Bin , Li Ding‐Guo , Lu Han‐Ming
Published: March 2007

Background/aims

Fibrosis occurs in most chronic liver injuries and results from changes in the balance between synthesis and degradation of extracellular matrix (ECM) components. Matrix metalloproteinases (MMPs) and their endogenous inhibitors (TIMPs) are known to regulate the ECM turnover. We investigate the effect of modified synthetic small interfering RNA (siRNA) targeting TIMP‐2 in rat model of liver fibrosis.

Methods

Rat hepatic fibrosis was induced by CCl4 for 8 weeks. After the 2‐week CCl4 injection period, rats in the three siRNA groups simultaneously received a different dosage (0.05, 0.1 and 0.2 mg·kg−1, respectively) of modified synthetic siRNA targeting TIMP‐2 via the tail vein every 3 days for 6 weeks. The pathological changes in liver tissues were observed by light microscopy and transmission electron microscopy. Portal vein pressure and proliferating cell nuclear antigen were measured. Expression of TIMP‐2, MMP‐2, MT1‐MMP, MMP‐13, hepatocyte growth factor, collagen type I, collagen type III and α‐SMA were evaluated by quantitative real‐time polymerase chain reaction or Western blotting or gelatin zymography.

Results

Modified synthetic siRNA targeting TIMP‐2 induced a dose‐dependent inhibition of the TIMP‐2 expression in the rat model of liver fibrosis with a similar trend in MMP‐2 and MT1‐MMP, but an increase in MMP‐13. Rats administered siRNA targeting TIMP‐2 showed promotion of ECM degradation, reduction in activated hepatic stellate cells and enhancement of hepatocyte regeneration. Furthermore, portal hypertension was also ameliorated after treatment with siRNA targeting TIMP‐2.

Conclusions

Knock‐down of TIMP‐2 expression attenuates CCl4‐induced liver fibrosis and is a potential pharmacological target for gene therapy in liver fibrosis. Copyright © 2007 John Wiley & Sons, Ltd.
Cell cycle dependent transcription, a determinant factor of heterogeneity in cationic lipid‐mediated transgene expression
Authors: Akita Hidetaka , Ito Rie , Kamiya Hiroyuki , Kogure Kentaro , Harashima Hideyoshi
Published: March 2007

Background

Heterogeneity of transgene expression, the presence or absence (below the limit of detection) of transgene expression on a cell‐by‐cell basis, is a severe disadvantage in the use of cationic lipid‐mediated gene vectors for gene therapy and experiments in molecular biology. Understandings of intracellular trafficking and the function (transgene expression) of vectors related to cellular physiology are essential in terms of clarifying the mechanism underlying the heterogeneity.

Methods

To distinguish the contribution of nuclear transfer efficiency and subsequent intranuclear transcription efficiency to the overall heterogeneity in transgene expression, a novel imaging system was established for the dual visualization of the nuclear transfer of pDNA and marker gene expression (lacZ) in single cells.

Results

The expression of LacZ occurred in only approximately 30% of HeLa cells of the nuclear pDNA‐positive cells, indicating that intranuclear transcription efficiency contributed to the heterogeneity. Dual imaging against synchronized cells further revealed that the efficiency of nuclear delivery was comparable irrespective of cell cycle status, which is contrary to the generally accepted hypothesis that nuclear import of pDNA is enhanced during cell division when the nuclear membrane structure is perturbed. The most significant finding in the present study is that nuclear transcription efficiency in terms of the ratio of LacZ‐positive cells to nuclear pDNA‐positive cells drastically increased in the late S and G2/M phase.

Conclusions

This is the first demonstration to show that cell cycle dependent intranuclear transcription appears to be responsible for the overall heterogeneity of transgene expression. Copyright © 2007 John Wiley & Sons, Ltd.
Corneal epithelium as a platform for secretion of transgene products after transfection with liposomal gene eyedrops
Authors: Toropainen Elisa , Hornof Margit , Kaarniranta Kai , Johansson Pinja , Urtti Arto
Published: March 2007

Background

The first objective of the study was to evaluate the transfection of corneal epithelium with non‐viral vectors to secrete transgene products into the tear fluid and aqueous humor. The second goal was to evaluate the differentiated corneal epithelial cell culture for transfection studies.

Methods

The human corneal epithelial (HCE) cell line was cultured to different stages of differentiation and transfected with complexes of pCMV‐SEAP2 with DOTAP/DOPE, DOTAP/DOPE/protamine sulfate (PS) and polyethylenimine (PEI). The complexes of DOTAP/DOPE with plasmid (CMV‐SEAP2 or pCMV‐Luc4) were subsequently applied topically to the rabbit eyes. Secreted alkaline phosphatase (SEAP) was analyzed using chemiluminescent assay. Luciferase (Luc) was detected at the mRNA level in cornea and conjunctiva using a qRT‐PCR.

Results

The transfection levels decreased with differentiation of HCE cells. PEI was effective in transfecting both the dividing and partly differentiated cells, but ineffective in differentiated cells. DOTAP/DOPE showed high activity in differentiated cell cultures, while added PS did not improve transfection. Significant SEAP expression was observed for three days after in vivo transfection in the tear fluid and aqueous humor. The luciferase mRNA was found both in the cornea and conjunctiva. The rates of SEAP secretion from both the basolateral side of differentiated HCE cells and cornea in vivo were within the same range.

Conclusions

Corneal epithelium can be transfected topically to secrete gene products to the tear fluid and aqueous humor. The differentiated HCE model is a useful tool in the evaluation of non‐viral carriers for corneal transfection. Copyright © 2007 John Wiley & Sons, Ltd.
Synthesis of PHA‐690509 labelled with 14C
Authors: Fontana E. , Giribone D. , Felicini C.
Published: March 2007

PHA‐690509, a cyclin‐dependent kinase A inhibitor, has been labelled with carbon‐14. [14C]PHA‐690509 was obtained via a three‐step procedure in 10% overall radiochemical yield starting from [14C]thiourea 3. Copyright © 2007 John Wiley & Sons, Ltd.
Uterine epithelial changes during placentation in the viviparous skink Eulamprus tympanum
Authors: Adams Susan M. , Lui Sylvia , Jones Susan M. , Thompson Michael B. , Murphy Christopher R.
Published: March 2007

We used scanning electron microscopy (SEM) and transmission electron microscopy (TEM) to describe the complete ontogeny of simple placentation and the development of both the yolk sac placentae and chorioallantoic placentae from nonreproductive through postparturition phases in the maternal uterine epithelium of the Australian skink, Eulamprus tympanum. We chose E. tympanum, a species with a simple, noninvasive placenta, and which we know, has little net nutrient uptake during gestation to develop hypotheses about placental function and to identify any difference between the oviparous and viviparous conditions. Placental differentiation into the chorioallantoic placenta and yolk sac placenta occurs from embryonic Stage 29; both placentae are simple structures without specialized features for materno/fetal connection. The uterine epithelial cells are not squamous as previously described by Claire Weekes, but are columnar, becoming increasingly attenuated because of the pressure of the impinging underlying capillaries as gestation progresses. When the females are nonreproductive, the luminal uterine surface is flat and the microvillous cells that contain electron‐dense vesicles partly obscure the ciliated cells. As vitellogenesis progresses, the microvillous cells are less hypertrophied than in nonreproductive females. After ovulation and fertilization, there is no regional differentiation of the uterine epithelium around the circumference of the egg. The first differentiation, associated with the chorioallantoic placentae and yolk sac placentae, occurs at embryonic Stage 29 and continues through to Stage 39. As gestation proceeds, the uterine chorioallantoic placenta forms ridges, the microvillous cells become less hypertrophied, ciliated cells are less abundant, the underlying blood vessels increase in size, and the gland openings at the uterine surface are more apparent. In contrast, the yolk sac placenta has no particular folding with cells having a random orientation and where the microvillous cells remain hypertrophied throughout gestation. However, the ciliated cells become less abundant as gestation proceeds, as also seen in the chorioallantoic placenta. Secretory vesicles are visible in the uterine lumen. All placental differentiation and cell detail is lost at Stage 40, and the uterine structure has returned to the nonreproductive condition within 2 weeks. Circulating progesterone concentrations begin to rise during late vitellogenesis, peak at embryonic Stages 28–30, and decline after Stage 35 in the later stages of gestation. The coincidence between the time of oviposition and placental differentiation demonstrates a similarity during gestation in the uterus between oviparous and simple placental viviparous squamates. J. Morphol., 2007. © 2007 Wiley‐Liss, Inc.
Hepatic parenchymal changes after ethanol injection in rabbits: Correlation of conventional and dynamic MR imaging with pathologic findings
Authors: Fujita Takeshi , Ito Katsuyoshi , Choji Takashi , Honjo Kazumitsu , Arita Takeshi , Matsunaga Naofumi
Published: March 2007

The purpose of this study is to clarify the changes of peripheral normal liver parenchyma before and after ethanol injection, with respect to MR appearances and pathologic findings and, in so doing, to clinically evaluate the therapeutic effectiveness of percutaneous ethanol injection (PEI) therapy. The normal liver in 12 rabbits was injected with ethanol. We performed conventional and dynamic MR imaging and prepared the histopathologic specimens 1 week (group 1), 2 weeks (group 2), and 1 month (group 3) after ethanol injection. On conventional MR images, coagulative necrosis in the normal liver was demonstrated as an area of low signal intensity on T1‐weighted images and high signal intensity on T2‐weighted images in all groups. On dynamic MR images, contrast enhancement in the coagulative necrosis was not seen in groups 1 and 2; however, gradual and concentric enhancement was seen in the direction of the central necrotic portion from early‐to‐delayed phase image in group 3. Although signal intensity of the coagulative necrotic area in the normal liver after ethanol injection may mimic that of untreated or viable hepatocellular carcinoma (HCC) when clinically encountered on conventional MR images, coagulative necrosis of the normal liver parenchyma will be discriminated from viable HCC by using dynamic MR imaging.
Nephrotoxicity of high‐dose gadolinium compared with iodinated contrast
Authors: Prince Martin R. , Arnoldus Christina , Frisoli Joan K.
Published: March 2007

To determine if high‐dose gadolinium chelates are less nephrotoxic than iodinated contrast. Records of 342 patients who had received high‐dose gadolinium (.2 to .4 mmol/kg) for magnetic resonance imaging were reviewed to identify patients who had also received iodinated contrast for radiographic examinations. Their clinical course and laboratory data were reviewed to identify changes in serum creatinine attributable to the contrast agents. In 64 patients, serum creatinine data were available pre and post both gadolinium and iodinated contrast. The mean change in serum creatinine after gadolinium in these 64 patients was −.07 mg/dL (−6 μmol/L). By comparison, the mean change in serum creatinine in the same patients after iodinated contrast was .35 mg/dL (+31 μmol/L) from 2.0 ± 1.4 to 2.3 ± 1.8 (P=.002). Eleven of the 64 patients had iodinated contrast‐induced renal failure (.5 mg/dL or greater rise in serum creatinine); none had gadolinium contrast‐induced renal failure despite the high gadolinium dose and high prevalence of underlying renal insufficiency. High‐dose gadolinium chelates are significantly less nephrotoxic than iodinated contrast.
The investigation of single bacteria by means of fluorescence staining and Raman spectroscopy
Authors: Krause M. , Radt B. , Rösch P. , Popp J.
Published: March 2007

The successful combination of Raman spectroscopy and fluorescence labelling of single bacterial cells is presented. The results show that the selected dyes (DAPI, SYTO 9, CFDA, SYTOX blue and PI) in most cases do not influence the Raman spectrum of a labelled bacterium significantly compared to an unstained bacterium spectrum. The labelling of bacteria offers the possibility of live/dead or biotic/abiotic differentiation prior to a Raman identification step. Copyright © 2007 John Wiley & Sons, Ltd.
Variation in forage quality and chemical composition among Italian accessions of Bituminaria bituminosa (L.) Stirt.
Authors: Pecetti Luciano , Tava Aldo , Pagnotta Mario A , Russi Luigi
Published: March 2007

Native Bituminaria bituminosa (L.) Stirt. accessions from central and southern Italy were evaluated for chemical composition to assess their nutritional value as forages. The germplasm was evaluated subjectively ex situ for intensity of ‘oil’ smell and analysed for fibre fraction, crude protein and water‐soluble carbohydrate contents as well as furanocoumarin (psoralen and angelicin) concentration. Total phenolics and their antioxidant activity were also evaluated. The quality parameters indicated this species as a good forage source, showing nutritive values similar to those of other wild legume species. Psoralen and angelicin contents ranged from 2.8 to 5.4 and from 2.3 to 4.7 mg g−1 dry weight respectively, while total phenolic concentrations were between 11.2 and 13.5 mg g−1 dry weight. Correlations among forage quality parameters, chemical components and climatic features at sites of origin were also assessed. Copyright © 2007 Society of Chemical Industry
The effect of supplementation of a white clover or perennial ryegrass diet with grape seed extract on indole and skatole metabolism and the sensory characteristics of lamb
Authors: Schreurs Nicola M , Tavendale Michael H , Lane Geoffrey A , Barry Tom N , McNabb Warren C , Cummings Tracey , Fraser Karl , López‐Villalobos Nicolas
Published: March 2007

Condensed tannin in the form of a grape seed extract (GSE) was dosed to weaned wether lambs fed white clover (WC) or perennial ryegrass (PRG) over a 9‐week period to determine whether the ‘pastoral’ flavour and odour of meat could be altered. The concentrations of the pastoral flavour compounds indole and skatole were determined in the rumen fluid, blood plasma and intermuscular fat. The odour and flavour of fat and meat from the slaughtered lambs was assessed by a trained panel. The rumen fluid and blood plasma concentrations of indole and skatole were higher in those lambs fed WC compared to PRG (P < 0.05) and the overall meat flavour intensity was greater when feeding WC (P < 0.01). The observed concentration of indole and skatole in the fat between WC and PRG feeding treatments was not statistically different. Power analysis indicated that increasing the number of lambs per treatment group from 20 to 65 would result in a higher fat skatole concentration (P < 0.05) being detected in lambs fed WC compared to PRG. Dosing with GSE gave a small reduction in skatole concentration in the rumen fluid and reduced plasma concentration of indole and skatole (P < 0.001). Odour and flavour scores of the fat and meat samples were not particularly high however, dosing with GSE lowered the overall and sweet odour and the sheepy, camphor, faecal and barnyard flavour (P < 0.05). Although the plasma concentration of indole and skatole suggests that GSE reduced indole and skatole formation, the intermittent supply of the GSE to the rumen environment was not sufficient to reduce their concentration in the fat. Hence, the small difference in the scores for pastoral odour and flavour attributes associated with GSE treatment may arise from other unknown factors. From a primary investigation, there was no difference in the concentration of indole and skatole in fat samples collected from carcasses before and after chilling. Further investigations into meat pastoral flavour are warranted through feeding condensed tannin‐containing forages. Copyright © 2007 Society of Chemical Industry
Effects of probiotic, prebiotic and synbiotic follow‐up infant formulas on large intestine morphology and bone mineralisation in rats
Authors: Pérez‐Conesa Darío , López Ginés , Ros Gaspar
Published: March 2007

The effects of powder functional follow‐up infant formulas on the morphology of the large intestine and the bone mineral content in rats were investigated. Infant formulas were supplemented with probiotics (Bifidobacterium bifidum and Bifidobacterium longum), prebiotics (galacto‐oligosaccharides (4′‐GOS) at 12, 50 and 100 g kg−1) or synbiotics (bifidobacteria and 4′‐GOS) and administered to seven groups of weanling rats over 30 days. After sacrificing the animals, the caecum and colon were removed and the luminal content pH and the crypt depth and cell density within the epithelial layer were measured. Results showed that groups fed synbiotic diets had significantly (P < 0.05) lower caecal and colonic content pH values compared with the control group. However, no test diet significantly modified the crypt depth or cell density in the caecum. In contrast, all seven test diets significantly increased (P < 0.05) the crypt depth in both the proximal and distal portions of the colon. There was a high correlation (Pearson correlation coefficient 0.870) between caecal and colonic content pH values. On the other hand, colonic content pH was negatively correlated with crypt depth in both the proximal and distal colon and with cell density in the distal colon. The authors previously reported increases in calcium, magnesium and phosphorus absorption using the same infant formulas. In the present study it was concluded that the increase in calcium absorption took place in the distal colon whereas magnesium absorption increased in both the proximal and distal colon, and their contents (especially that of calcium) increased in both the femur and tibia. Copyright © 2007 Society of Chemical Industry
Effect of modified starch concentration and freezing and thawing rates on properties of mashed potatoes (cv. Kennebec)
Authors: Álvarez M Dolores , Canet Wenceslao , Fernández Cristina
Published: March 2007

Effects of modified cornstarch concentration, freezing rate and thawing mode on quality properties of mashed potatoes were examined. The product was tested by oscillatory rheometry, instrumental texture profile analysis (ITPA) and cone penetration, colour, dry matter (DM) and sensory analyses. Oscillatory parameters showed that increasing starch concentration resulted in a softer product in which gel strength decreased in direct proportion to concentration in quick‐frozen and microwave‐thawed product. Quick freezing made for firmer mashed potatoes, whereas oscillatory, ITPA and penetration parameters were lower in the samples thawed at 4 °C. Starch concentration and instrumental consistency and firmness were directly proportional to one another. Adding starch at the highest concentration, quick freezing and slow thawing produced a lighter‐coloured mashed potato, although the loss of colour in the processed product was not detected by panellists in the microwave‐thawed samples. DM was higher in the quick‐frozen samples and lower in air‐thawed samples. The factors studied affected different sensory texture parameters but had hardly any effect on attributes perceived during final and residual phases of mastication. Only starch concentration had a significant effect on sensory acceptability, but interactions between factors showed that starch addition followed by quick freezing was judged undesirable by the panellists due to excessive softening. Oscillatory parameters correlated well with sensory texture attributes and proved quite precise. They would therefore appear to be the best test to monitor properties of frozen mashed potatoes. Copyright © 2007 Society of Chemical Industry
Unique Orientation Textures Induced by Confined Crystal Growth of Poly(vinylidene fluoride) in Oriented Blends with Polyamide 6
Authors: Kaito Akira , Iwakura Yuko , Li Yongjin , Nakayama Kazuo , Shimizu Hiroshi
Published: March 2007

Unique orientation textures have been induced by the confined crystal growth of PVDF in drawn films of PVDF/PA6 blends. Oriented films of PVDF/PA6 blends were prepared by uniaxially drawing melt‐mixed blends. The drawn films with fixed lengths were heat‐treated at 180 °C for 3 minutes to melt the PVDF component, followed by non‐isothermal crystallization of PVDF at a cooling rate of 0.5 °C · min−1. The crystal orientation was studied by WAXD. When PVDF was melted and recrystallized in the drawn films of the PVDF/PA6 = 50/50 blend at a slow cooling rate, the crystal b‐axis of the α‐crystalline form of PVDF was oriented in the drawing direction, forming orthogonal orientation textures. SEM showed that stretched domains of PVDF with diameters of 0.2–0.5 µm were dispersed in the PA6 phase in the drawn films of the PVDF/PA6 = 50/50 blend. Spatial confinement of the crystal growth resulted in the alignment of the crystal b‐axis along the long axis of the domains, because PVDF is crystallized in thin cylindrical domains. The orientation behavior is different from the oriented crystallization of PVDF/PA11 (Y. Li, A. Kaito, Macromol. Rapid Commun. 2003, 24, 255), in which transcrystallization from the interface causes the a‐axis orientation to be in the drawing direction. It is thought that the domain size influenced the mechanism of oriented crystallization and the resultant crystal orientation.

magnified image
Protonation of Sulfonated Poly(4,4′‐diphenylether‐1,3,4‐oxadiazole) Membranes
Authors: Roeder Jerusa , Gomes Dominique , Ponce Mariela L. , Abetz Volker , Nunes Suzana P.
Published: March 2007

This work describes the effect of sulfuric acid protonation on the properties of SPOD‐DPE membranes using FT‐IR and impedance spectroscopic analyses. The IR spectra showed the protonation of nitrogen atoms from oxadiazole rings, with a broad band complex in the region 3 000–2 100 cm−1 with two centered peaks at 2 590 and 2 440 cm−1. The SO characteristic absorption bands in SPOD‐DPE and sulfuric acid were specially studied in the region of 1 800–900 cm−1. The band shifts are associated to the interaction between acid groups and oxadiazole ring nitrogen atoms. The IR spectra evidenced the presence of three absorption species (HSO, SO and free H2SO4) depending on the sulfuric acid concentration. For the protonated SPOD‐DPE membranes, a proton conductivity around 10 mS · cm−1 was reached at 50 °C.

magnified image
Composites of Single‐Walled Carbon Nanotubes and Styrene‐Isoprene Copolymer Latices
Authors: Ha Mai L. P. , Grady Brian P. , Lolli Giulio , Resasco Daniel E. , Ford Warren T.
Published: March 2007

Composites of a styrene‐isoprene copolymer and SWNTs were prepared by emulsion and miniemulsion polymerization in the presence of SWNTs, as well as by mixing dispersed SWNTs with a styrene‐isoprene copolymer latex after polymerization. For the former, the surfactant was displaced from SWNTs to monomer droplets leading to SWNT aggregation. Mixing dispersed SWNTs with latex after reaction was able to preserve SWNT dispersion and gave a polymer composite with an electrical percolation threshold of 0.2%. Dynamic mechanical measurements of film samples in tension showed that the composites had a measurable modulus above Tg, indicating entanglement formation. The modulus above Tg was strongly temperature dependent, confirming shear measurements that have shown entanglements in SWNT/polymer composites both polymer and nanotubes.

magnified image
Towards a Quantitative Interpretation of Polymer Distributions from MALDI‐TOF Spectra
Authors: Schnöll‐Bitai Irene , Hrebicek Thomas , Rizzi Andreas
Published: March 2007

The importance of proper conversion of MALDI‐MS signals into the number of polymers with a certain mass increment (by taking into account a nonconstant conversion factor) is demonstrated with calculated Schulz‐Zimm and Poisson distributions. Measurements of two narrow polystyrene standards were used to investigate the influence of measurement conditions (laser intensity, matrix) and data processing (signal conversion, baseline construction). We observed the following effects: (a) slightly broader distributions with DCTB as matrix at a given laser intensity in comparison to those obtained with all‐trans‐retinoic acid, (b) changes in the relative intensities of several peaks in a sample, and (c) a nonlinear baseline in the low molar mass region in most of the cases. Therefore, the implications of an assumed linear baseline instead of the correct one on the results were scrutinized experimentally and by simulations. In all, measurement of narrow distributions turned out to give reasonable results. Based on the assumption that the polymer standards can be described by Poisson distributions, overlap conditions between two distributions are rephrased. An alternative possibility of how mass discrimination could be determined, in principle, is presented, too.

magnified image
Some remarks on rearrangements and functionals with non‐constant density
Authors: Landes Ruediger
Published: March 2007

Conditions on non‐constant densities of energy functionals are discussed, such that monotone rearrangement of functions decreases the value of the functional. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A symmetrization result for Monge–Ampère type equations
Authors: Brandolini Barbara , Trombetti Cristina
Published: March 2007

In this paper we prove some comparison results for Monge–Ampère type equations in dimension two. We also consider the case of eigenfunctions and we derive a kind of “reverse” inequalities. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)