bluuebunny/crossref_metadata_2025 huggingface dataset:
MADS-box gene family in rice: genome-wide identification, organization and expression profiling during reproductive development and stress
Authors: Arora Rita , Agarwal Pinky , Ray Swatismita , Singh Ashok Kumar , Singh Vijay Pal , Tyagi Akhilesh K , Kapoor Sanjay
Published: July 2007

Background

MADS-box transcription factors, besides being involved in floral organ specification, have also been implicated in several aspects of plant growth and development. In recent years, there have been reports on genomic localization, protein motif structure, phylogenetic relationships, gene structure and expression of the entire MADS-box family in the model plant system, Arabidopsis. Though there have been some studies in rice as well, an analysis of the complete MADS-box family along with a comprehensive expression profiling was still awaited after the completion of rice genome sequencing. Furthermore, owing to the role of MADS-box family in flower development, an analysis involving structure, expression and functional aspects of MADS-box genes in rice and Arabidopsis was required to understand the role of this gene family in reproductive development.

Results

A genome-wide molecular characterization and microarray-based expression profiling of the genes encoding MADS-box transcription factor family in rice is presented. Using a thorough annotation exercise, 75 MADS-box genes have been identified in rice and categorized into MIKCc, MIKC*, Mα, Mβ and Mγ groups based on phylogeny. Chromosomal localization of these genes reveals that 16 MADS-box genes, mostly MIKCc-type, are located within the duplicated segments of the rice genome, whereas most of the M-type genes, 20 in all, seem to have resulted from tandem duplications. Nine members belonging to the Mβ group, which was considered absent in monocots, have also been identified. The expression profiles of all the MADS-box genes have been analyzed under 11 temporal stages of panicle and seed development, three abiotic stress conditions, along with three stages of vegetative development. Transcripts for 31 genes accumulate preferentially in the reproductive phase, of which, 12 genes are specifically expressed in seeds, and six genes show expression specific to panicle development. Differential expression of seven genes under stress conditions is also evident. An attempt has been made to gain insight into plausible functions of rice MADS-box genes by collating the expression data of functionally validated genes in rice and Arabidopsis.

Conclusion

Only a limited number of MADS genes have been functionally validated in rice. A comprehensive annotation and transcriptome profiling undertaken in this investigation adds to our understanding of the involvement of MADS-box family genes during reproductive development and stress in rice and also provides the basis for selection of candidate genes for functional validation studies.
What is the empirical evidence that hospitals with higher-risk adjusted mortality rates provide poorer quality care? A systematic review of the literature
Authors: Pitches David W , Mohammed Mohammed A , Lilford Richard J
Published: July 2007

Background

Despite increasing interest and publication of risk-adjusted hospital mortality rates, the relationship with underlying quality of care remains unclear. We undertook a systematic review to ascertain the extent to which variations in risk-adjusted mortality rates were associated with differences in quality of care.

Methods

We identified studies in which risk-adjusted mortality and quality of care had been reported in more than one hospital. We adopted an iterative search strategy using three databases – Medline, HealthSTAR and CINAHL from 1966, 1975 and 1982 respectively. We identified potentially relevant studies on the basis of the title or abstract. We obtained these papers and included those which met our inclusion criteria.

Results

From an initial yield of 6,456 papers, 36 studies met the inclusion criteria. Several of these studies considered more than one process-versus-risk-adjusted mortality relationship. In total we found 51 such relationships in a widen range of clinical conditions using a variety of methods. A positive correlation between better quality of care and risk-adjusted mortality was found in under half the relationships (26/51 51%) but the remainder showed no correlation (16/51 31%) or a paradoxical correlation (9/51 18%).

Conclusion

The general notion that hospitals with higher risk-adjusted mortality have poorer quality of care is neither consistent nor reliable.
Effect of dsDNA binding to SmD-derived peptides on clinical accuracy in the diagnosis of systemic lupus erythematosus
Authors: Mahler Michael , Waka Aderajew , Hiepe F , Fritzler Marvin J
Published: July 2007

Systemic lupus erythematosus is characterized by antibodies to a variety of intracellular self-antigens, such as dsDNA and Sm, and these serve as hallmarks in the diagnosis of systemic autoimmune diseases. Several studies have shown that SmD1 and SmD3 synthetic peptides represent highly functional antigens for autoantibody detection and thus for diagnostic applications. The present study analysed the technical and clinical accuracy of an anti-SmD1 (amino acids 83–119) and an anti-SmD3 (amino acids 108–122) ELISA for the detection of anti-Sm antibodies. Depending on the cut-off value of the SmD1 ELISA, we found a high degree of concordance between the two tests. At an optimized cut-off value of 100 units for SmD1 we found the same clinical sensitivity (12.5%) and specificity (100%) in a group of systemic lupus erythematosus patients (n = 48) and in controls (n = 99). The concordance at this cut-off value was 100% (P < 0.0001; χ2 = 127.61). Using a second panel of sera (n = 65) preselected based on positive anti-Sm results, we confirmed the high degree of concordance between the two assays. Using dsDNA-coated ELISA plates and biotinylated peptides we confirmed the high dsDNA binding properties for SmD1, which were significantly higher than the SmD3-derived peptide. However, no cross-linking of anti-dsDNA antibodies to SmD1 was observed after adding increasing amounts of dsDNA to anti-dsDNA positive, anti-SmD1 negative serum. We therefore conclude that the reported difference in the sensitivity is related to the different cut-off levels and not to the detection of anti-dsDNA antibodies bridged via dsDNA to the SmD1 peptide. Moreover, we found that a subpopulation of anti-Sm antibodies cross-reacted with SmD1 and SmD3. Taken together, the data indicate that both SmD peptide ELISAs represent accurate assays and may be used as important standards for the detection of anti-Sm antibodies.
Human meniscus cells express hypoxia inducible factor-1α and increased SOX9 in response to low oxygen tension in cell aggregate culture
Authors: Adesida Adetola B , Grady Lisa M , Khan Wasim S , Millward-Sadler S Jane , Salter Donald M , Hardingham Timothy E
Published: July 2007

In previous work we demonstrated that the matrix-forming phenotype of cultured human cells from whole meniscus was enhanced by hypoxia (5% oxygen). Because the meniscus contains an inner region that is devoid of vasculature and an outer vascular region, here we investigate, by gene expression analysis, the separate responses of cells isolated from the inner and outer meniscus to lowered oxygen, and compared it with the response of articular chondrocytes. In aggregate culture of outer meniscus cells, hypoxia (5% oxygen) increased the expression of type II collagen and SOX9 (Sry-related HMG box-9), and decreased the expression of type I collagen. In contrast, with inner meniscus cells, there was no increase in SOX9, but type II collagen and type I collagen increased. The articular chondrocytes exhibited little response to 5% oxygen in aggregate culture, with no significant differences in the expression of these matrix genes and SOX9. In both aggregate cultures of outer and inner meniscus cells, but not in chondrocytes, there was increased expression of collagen prolyl 4-hydroxylase (P4H)α(I) in response to 5% oxygen, and this hypoxia-induced expression of P4Hα(I) was blocked in monolayer cultures of meniscus cells by the hypoxia-inducible factor (HIF)-1α inhibitor (YC-1). In fresh tissue from the outer and inner meniscus, the levels of expression of the HIF-1α gene and downstream target genes (namely, those encoding P4Hα(I) and HIF prolyl 4-hydroxylase) were significantly higher in the inner meniscus than in the outer meniscus. Thus, this study revealed that inner meniscus cells were less responsive to 5% oxygen tension than were outer meniscus cells, and they were both more sensitive than articular chondrocytes from a similar joint. These results suggest that the vasculature and greater oxygen tension in the outer meniscus may help to suppress cartilage-like matrix formation.
Uptake and Intracellular Fate of Francisella tularensis in Human Macrophages
Authors: CLEMENS DANIEL L. , HORWITZ MARCUS A.
Published: July 2007

Abstract: 
Francisella tularensis is an intracellular pathogen that survives and multiplies within host mononuclear phagocytes. We have shown that uptake of the bacterium by human macrophages occurs by a novel process, “looping phagocytosis,” in which the bacterium is engulfed in a spacious, asymmetric, pseudopod loop. Whereas looping phagocytosis is resistant to treatment of the F. tularensis with formalin, proteases, or heat, the process is abolished by oxidation of the bacterial carbohydrates with periodate, suggesting a role for preformed surface carbohydrate molecules in triggering looping phagocytosis. Following uptake, F. tularensis initially resides in a spacious vacuole at the periphery of the cell, but this vacuole rapidly shrinks in size. The nascent F. tularensis vacuole transiently acquires early endosomal markers, but subsequently exhibits an arrested maturation, manifest by only limited amounts of lysosome‐associated membrane glycoproteins (consistent with limited interaction with late endosomes), nonfusion with lysosomes, and minimal acidification. In ultrastructural studies, we have observed that the F. tularensis phagosome displays a novel feature in that many of the phagosomes acquire an electron dense fibrillar coat. This fibrillar coat forms blebs and vesicles, and with time, is seen to be fragmented and disrupted. With increasing time after infection, increasing numbers of the F. tularensis are found free in the macrophage cytoplasm, such that by 14 h after infection, less than 15% of the bacteria are surrounded by any discernible phagosomal membrane. Further research is needed to determine the mechanisms underlying looping phagocytosis, and the maturational arrest, fibrillar coat formation, and disruption of the phagosome.
Mucosal Immunopathogenesis of Francisella tularensis
Authors: METZGER DENNIS W. , BAKSHI CHANDRA SHEKHAR , KIRIMANJESWARA GIRISH
Published: July 2007

Abstract:  Respiratory infection with Francisella tularensis is the deadliest form of disease and represents the most likely route to be used by bioterrorists. Although mucosal surfaces represent the first line of defense against respiratory tularemia, and in fact, against the great majority of human pathogens, little is known about protective immunity at these sites. The objective of this chapter is to review recent data examining the importance of various pulmonary immune mechanisms in defense against F. tularensis infection and to evaluate potential strategies for induction of protective lung immunity. Aerosol and intranasal mouse infection models have yielded essentially equivalent results and have implicated an important role for Th1‐type immune responses in protection, including IFN‐γ, TNF‐α, and IL‐12. The cells responsible for protection in the lung are not well‐characterized but NK cells are an early target for activation after infection although it appears that CD8 T cells might be most critical for host resistance. In addition, it is becoming increasingly clear that antibodies can provide prophylactic and therapeutic protection against pulmonary infection but only in the presence of active cell‐mediated immunity. In fact, in vitro exposure of resting macrophages to antibody‐coated bacteria in the absence of IFN‐γ can actually enhance infection. Although various immune mechanisms can be shown to be important for protection against attenuated strains such as LVS, the real challenge for the future is to design efficacious approaches to prevent disease by highly virulent strains such as SchuS4.
Tularemia: History, Epidemiology, Pathogen Physiology, and Clinical Manifestations
Authors: SJÖSTEDT ANDERS
Published: July 2007

Abstract: 
Francisella tularensis has been recognized as a human pathogen for almost 100 years and is the etiological agent of the zoonotic disease tularemia. Soon after its discovery, it became recognized as an important pathogen in several parts of the world, for example, in the United States and Soviet Union. The number of tularemia cases in the two countries peaked in the 1940s and has thereafter steadily declined. Despite this decline, there was still much interest in the pathogen in the 1950s and 1960s since it is highly infectious and transmissible by aerosol, rendering it a potent biothreat agent. In fact, it was one of the agents that was given the highest priority in the offensive programs of the United States and Soviet Union. After termination of the offensive programs in the 1960s, the interest in F. tularensis diminished significantly and little research was carried out for several decades. Outbreaks of tularemia during the last decade in Europe, for example, in Kosovo, Spain, and Scandinavia, led to a renewed public interest in the disease. This, together with a massive increase in the research funding, in particular in the United States since 2001, has resulted in a significant increase in the number of active Francisella researchers. This article summarizes, predominantly with a historical perspective, the epidemiology and clinical manifestations of tularemia and the physiology of F. tularensis.
Molecular and Genetic Basis of Pathogenesis in Francisella Tularensis
Authors: BARKER JEFFREY R. , KLOSE KARL E.
Published: July 2007

Abstract:  The genetic means of pathogenesis of Francisella tularensis are poorly understood. F. tularensis is able to survive and replicate within macrophages, and a virulence factor, MglA, has been identified that is essential for this ability. MglA regulates the transcription of genes necessary for intracellular growth, including those located within the Francisella Pathogenicity Island (FPI). The FPI genes are required for intramacrophage growth and virulence, and appear to encode a protein secretion system, but the exact function of individual FPI proteins remains to be determined. Additional regulatory factors required for virulence have recently been discovered, as well a number of virulence genes identified through transposon mutant screens. The role of surface components, including LPS, pili, and capsule, in F. tularensis virulence is also beginning to be illuminated. The identification of virulence genes has enabled the study of defined attenuated mutants as live vaccine strains against tularemia. As new components of the F. tularensis virulence gene repertoire are discovered, we will achieve a better understanding of how this bacterium interacts with the host and evades immune function, which will facilitate the development of therapeutic and preventive measures against tularemia.
Molecular Epidemiology, Evolution, and Ecology of Francisella
Authors: KEIM PAUL , JOHANSSON ANDERS , WAGNER DAVID M.
Published: July 2007

Abstract:  Tularemia is a disease caused by several subspecies of Francisella tularensis, although the severity of the disease varies greatly from subspecies to subspecies. Currently, there are four recognized subspecies (tularensis, holarctica, mediasiatica, and novicida), in addition to a second Francisella species, F. philomiragia. It is clear from molecular sampling of the environment that these human pathogens are a mere fraction of the Francisella diversity. Taxonomic nomenclature is now being based upon several DNA‐sequence‐based approaches and this advance provides for robust phylogenetic models that are guiding the systematics of this genus. This in turn allows for better molecular epidemiological investigations and more precise ecological analysis. Tularemia ecology is still only partially understood, with many knowledge gaps about the disease reservoir and vectors. Molecular analysis has identified a major population split within F. tularensis subsp. tularensis that points toward distinctive ecological adaptations, vectors, and host species. Current medical practice does not rely upon subspecies or subpopulation identification, although this information may have predictive value for clinical outcome, especially in the United States. Combined molecular and epidemiological analyses suggest that the population split in F. tularensis subsp. tularensis matches two distinct human diseases in the United States with different mortality rates. DNA‐sequence‐based typing of F. tularensis subsp. holarctica from tularemia outbreaks in Europe and the United States proves regional identity among isolates and also demonstrates that this subspecies successfully disseminated worldwide in recent evolutionary time.
Francisella Tularensis Genomics and Proteomics
Authors: TITBALL RICHARD W. , PETROSINO JOSEPH F.
Published: July 2007

Abstract:  The availability of the genome sequences of different strains of Francisella tularensis is having a major impact on a wide range of research projects, from understanding the biology of this organism to devising vaccines and diagnostics. Comparative genomics and molecular typing methods suggest that the four different subspecies of F. tularensis are genetically distinct groups. Although there is a high degree of nucleotide identity between strains, there are numerous DNA rearrangements. IS elements appear to have played a major role in these chromosomal rearrangements. The different subspecies of F. tularensis appear to have evolved by vertical descent from a common ancestor, probably F. tularensis subspecies novicida. Comparative genomic and proteomic studies have revealed possible reasons for the different virulence of different strains and a range of candidate virulence genes have been identified including those located on the Francisella pathogenicity island. Proteomic studies have identified proteins which are produced at elevated levels in vivo, and proteins which are recognized by immune or convalescent sera. These proteins might be exploited as components of vaccines or diagnostic systems.
Phase I Clinical Study of AZD2171, an Oral Vascular Endothelial Growth Factor Signaling Inhibitor, in Patients With Advanced Solid Tumors
Authors: Drevs Joachim , Siegert Patrizia , Medinger Michael , Mross Klaus , Strecker Ralph , Zirrgiebel Ute , Harder Jan , Blum Hubert , Robertson Jane , Jürgensmeier Juliane M. , Puchalski Thomas A. , Young Helen , Saunders Owain , Unger Clemens
Published: July 2007

Purpose

AZD2171 is a highly potent oral selective inhibitor of vascular endothelial growth factor (VEGF) signaling. This phase I study was designed to evaluate the safety and tolerability of increasing doses of AZD2171, with additional assessments of pharmacokinetics, pharmacodynamics, and efficacy.

Patients and Methods

In part A, 36 patients with solid tumors and liver metastases refractory to standard therapies received once-daily oral AZD2171 (0.5 to 60 mg). Doses were escalated in successive cohorts until the maximum-tolerated dose was identified. In part B, patients with (n = 36) or without (n = 11) liver metastases were randomly assigned to receive once-daily AZD2171 (20, 30, or 45 mg). In both parts, treatment continued until tumor progression or dose-limiting toxicity (DLT) was observed.

Results

Eighty-three patients received AZD2171, which was generally well tolerated at doses of 45 mg/d or less; the most frequently reported dose-related adverse events were diarrhea, dysphonia, and hypertension. The most common DLT was hypertension (n = 7), which occurred at AZD2171 doses of 20 mg and higher. After a single dose, maximum plasma (peak) drug concentration after single-dose administration (Cmax) was achieved 1 to 8 hours postdosing with an arithmetic mean half-life associated with terminal slope of a semilogarithmic concentration-time curve (t1/2λz) of 22 hours. Pharmacodynamic assessments demonstrated time-, dose-, and exposure-related decreases in initial area under the curve, defined over 60 seconds post-contrast arrival in the tissue (iAUC60) using dynamic contrast-enhanced magnetic resonance imaging, as well as dose- and time-dependent reductions in soluble VEGF receptor 2 levels. Preliminary evidence of efficacy included two confirmed partial responses and 22 patients with stable disease; effects on tumor size appeared to be dose related.

Conclusion

Once-daily oral AZD2171 at doses of 45 mg or less was generally well tolerated and was associated with encouraging antitumor activity in patients with a broad range of advanced solid tumors.
Doctors’ and Patients’ Preferences for Participation and Treatment in Curative Prostate Cancer Radiotherapy
Authors: Stalmeier Peep F.M. , van Tol-Geerdink Julia J. , van Lin Emile N.J.Th. , Schimmel Erik , Huizenga Henk , van Daal Willem A.J. , Leer Jan-Willem
Published: July 2007

Purpose

Physicians hold opinions about unvoiced patient preferences, so-called substitute preferences. We studied whether doctors can predict preferences of patients supported with a decision aid.

Methods

A total of 150 patients with prostate cancer facing radiotherapy were included. After the initial consultation, without discussing any treatment choice, physicians gave substitute judgments for patients' decision-making and radiation dose preferences. Physicians knew that several weeks later, patients would be empowered by a decision aid supporting a choice between two radiation doses involving a trade-off between disease-free survival and adverse effects. Subsequently, patient preferences for decision making (whether or not they wanted to choose a radiation dose) and for treatment (low or high dose) were obtained. The chosen radiation dose actually was administered.

Results

Of the patients studied, 79% chose a treatment; physicians believed that 66% of the patients wanted to choose. Agreement was poor (64%; κ = 0.13; P = .11), and was better as patients became more hopeful (odds ratio [OR] = 4.4 per unit; P = .001) and as physicians' experience increased (OR = 1.09 per year; P = .02). Twenty percent of physicians' preferences, 51% of physicians' substitute preferences, and 71% of patients' preferences favored the lower dose; agreement was again poor (70%; κ = 0.2; P = .03).

Conclusion

Physicians had problems predicting the preferences of patients empowered with a decision aid. They slightly underestimated patients' decision-making preferences, and underestimated patients' preferences for the less toxic treatment. Counseling might be improved by first informing patients—possibly using a decision aid—before discussing patient preferences.
Phase III Randomized Controlled Trial Comparing the Survival of Patients With Unresectable Hepatocellular Carcinoma Treated With Nolatrexed or Doxorubicin
Authors: Gish Robert G. , Porta Camillo , Lazar Lucian , Ruff Paul , Feld Ronald , Croitoru Adina , Feun Lynn , Jeziorski Krzysztof , Leighton John , Knox Jennifer , Gallo José , Kennealey Gerard T.
Published: July 2007

Purpose

The study objective was to compare the overall survival (OS) of patients with unresectable or metastatic hepatocellular carcinoma (HCC) treated with nolatrexed (NOL) or doxorubicin (DOX).

Patients and Methods

Patients from North America, Europe, and South Africa (N = 445) with HCC were randomly assigned to receive NOL or DOX. Eligible patients had Karnofsky performance status (KPS) ≥ 60%, Cancer of the Liver Italian Program (CLIP) score ≤ 3, and adequate organ function. Primary end point was OS. Secondary end points included progression-free survival (PFS), objective response rates, and safety. The treatment groups were well-balanced with regards to age, sex, ethnic origin, and underlying liver disease. Randomization was stratified according to KPS and CLIP score.

Results

At the time of the final analysis, 377 patients had died. Median OS was 22.3 weeks for NOL and 32.3 weeks for DOX (P = .0068). The hazard ratio was 0.753 in favor of DOX. Objective response rate (complete response [CR] plus partial response [PR]) was 1.4% for NOL and 4.0% for DOX. Median PFS was 12 weeks for NOL and 10 weeks for DOX (P = .7091). Median time to treatment failure was 8.4 weeks for NOL and 9.1 weeks for DOX (P = .0969). Grade 3 and 4 stomatitis, vomiting, diarrhea, and thrombocytopenia were more common in the NOL arm. Alopecia was more common in the DOX arm. More patients were withdrawn from study for toxicity in the NOL arm than in the DOX arm.

Conclusion

NOL showed minimal activity in this phase III trial. Further exploration at this dose and schedule in HCC is not warranted.
Coronary Artery Findings After Left-Sided Compared With Right-Sided Radiation Treatment for Early-Stage Breast Cancer
Authors: Correa Candace R. , Litt Harold I. , Hwang Wei-Ting , Ferrari Victor A. , Solin Lawrence J. , Harris Eleanor E.
Published: July 2007

Purpose

To compare the incidence and distribution of coronary artery disease after left-sided versus right-sided irradiation in patients treated with breast conservation for early-stage breast cancer who subsequently underwent cardiac stress testing and/or catheterization for cardiovascular symptoms.

Patients and Methods

The medical records of 961 stage I-II breast cancer patients treated from 1977 to 1995 at the University of Pennsylvania with conventional tangential beam radiation treatment (RT) were screened for cardiac stress tests and catheterizations performed after RT. The results of these tests were analyzed by laterality of RT and compared with baseline cardiovascular risk.

Results

At diagnosis, patients with left-sided and right-sided breast cancer had the same estimated 10-year risk (both 7%) of developing coronary artery disease. At a median time of 12 years post-RT (range, 2 to 24 years), 46 patients with left-sided and 36 patients with right-sided breast cancer (total, N = 82) had undergone cardiac stress testing. A statistically significant higher prevalence of stress test abnormalities was found among left (27 of 46; 59%) versus right-side irradiated patients (three of 36; 8%; P = .001). Furthermore, 19 of 27 of left-sided abnormalities (70%) were in the left anterior descending artery territory. Thirteen left-side irradiated patients also underwent cardiac catheterization revealing 12 of 13 with coronary stenoses (92%) and eight of 13 with coronary stenoses (62%) solely in the left anterior descending artery.

Conclusion

Patients treated with left-sided radiation as a component of breast conservation have an increased risk of late, radiation-associated coronary damage. Treatment with modern radiation techniques may reduce the risk of cardiac injury.
Randomized Trial of Laparoscopic-Assisted Resection of Colorectal Carcinoma: 3-Year Results of the UK MRC CLASICC Trial Group
Authors: Jayne David G. , Guillou Pierre J. , Thorpe Helen , Quirke Philip , Copeland Joanne , Smith Adrian M.H. , Heath Richard M. , Brown Julia M.
Published: July 2007

Purpose

The aim of the current study is to report the long-term outcomes after laparoscopic-assisted surgery compared with conventional open surgery within the context of the UK MRC CLASICC trial. Results from randomized trials have indicated that laparoscopic surgery for colon cancer is as effective as open surgery in the short term. Few data are available on rectal cancer, and long-term data on survival and recurrence are now required.

Methods

The United Kingdom Medical Research Council Conventional versus Laparoscopic-Assisted Surgery in Colorectal Cancer (UK MRC CLASICC; clinical trials number ISRCTN 74883561) trial study comparing conventional versus laparoscopic-assisted surgery in patients with cancer of the colon and rectum. The randomization ratio was 2:1 in favor of laparoscopic surgery. Long-term outcomes (3-year overall survival [OS], disease-free survival [DFS], local recurrence, and quality of life [QoL]) have now been determined on an intention-to-treat basis.

Results

Seven hundred ninety-four patients were recruited (526 laparoscopic and 268 open). Overall, there were no differences in the long-term outcomes. The differences in survival rates were OS of 1.8% (95% CI, −5.2% to 8.8%; P = .55), DFS of −1.4% (95% CI, −9.5% to 6.7%; P = .70), local recurrence of −0.8% (95% CI, −5.7% to 4.2%; P = .76), and QoL (P > .01 for all scales). Higher positivity of the circumferential resection margin was reported after laparoscopic anterior resection (AR), but it did not translate into an increased incidence of local recurrence.

Conclusion

Successful laparoscopic-assisted surgery for colon cancer is as effective as open surgery in terms of oncological outcomes and preservation of QoL. Long-term outcomes for patients with rectal cancer were similar in those undergoing abdominoperineal resection and AR, and support the continued use of laparoscopic surgery in these patients.
Topotecan Is Active Against Wilms’ Tumor: Results of a Multi-Institutional Phase II Study
Authors: Metzger Monika L. , Stewart Clinton F. , Freeman Burgess B. , Billups Catherine A. , Hoffer Fredric A. , Wu Jianrong , Coppes Max J. , Grant Ronald , Chintagumpala Murali , Mullen Elizabeth A. , Alvarado Carlos , Daw Najat C. , Dome Jeffrey S.
Published: July 2007

Purpose

A phase II study was conducted to evaluate the activity and safety of topotecan in pediatric patients with recurrent Wilms' tumor.

Patients and Methods

Patients with favorable histology Wilms' tumor (FHWT) and recurrence after at least one salvage chemotherapy regimen or with anaplastic histology Wilms' tumor (AHWT) in first or subsequent recurrence were eligible. Patients were stratified according to histology, with statistical considerations based on the FHWT stratum. Topotecan was administered intravenously over 30 minutes for 5 days on 2 consecutive weeks. Treatment dosages were adjusted to achieve a target area under the curve (AUC) of 80 ± 10 ng/mL*h. Tumor responses were measured after two cycles of treatment.

Results

Thirty-seven patients (26 patients with FHWT) were enrolled and received a total of 94 cycles of topotecan (range, one to six cycles). The median topotecan dosage required to achieve the target AUC was 1.8 mg/m2(range, 0.7 to 3.2 mg/m2). Of 25 assessable patients with FHWT, 12 had partial response (PR), six had stable disease (SD), and seven had progressive disease (PD), for an overall response rate of 48% (95% CI, 27.8% to 68.7%). Of 11 assessable patients with AHWT, two had PR, one had SD, and eight had PD. The main toxicities were grade 3 and 4 neutropenia (median duration, 13 days) and thrombocytopenia (median duration, 7.5 days).

Conclusion

Topotecan administered on a protracted schedule is active against recurrent FHWT. Inclusion of topotecan in front-line clinical trials for patients with recurrent Wilms' tumor should be considered.
Phase I and Pharmacokinetic Study of Erlotinib for Solid Tumors in Patients With Hepatic or Renal Dysfunction: CALGB 60101
Authors: Miller Antonius A. , Murry Daryl J. , Owzar Kouros , Hollis Donna R. , Lewis Lionel D. , Kindler Hedy L. , Marshall John L. , Villalona-Calero Miguel A. , Edelman Martin J. , Hohl Raymond J. , Lichtman Stuart M. , Ratain Mark J.
Published: July 2007

Purpose

We investigated dose and pharmacokinetics of erlotinib in patients with hepatic dysfunction or renal dysfunction.

Patients and Methods

Patients were assigned to one of three cohorts: cohort 1, AST ≥ 3× upper limit of normal; cohort 2, direct bilirubin of 1 to 7 mg/dL; and cohort 3, creatinine of 1.6 to 5.0 mg/dL. Cohort 1a was amended for albumin less than 2.5 g/dL. Erlotinib was administered orally daily to groups of at least three assessable patients in escalating doses of 50, 75, 100, and 150 mg, starting with 50 mg in hepatic dysfunction patients and 75 mg in renal dysfunction patients.

Results

Between December 2001 and May 2005, 55 patients were accrued. The distribution of assessable patients was: two of three in cohort 1, three of three in cohort 1a, 16 of 30 in cohort 2, and 18 of 18 in cohort 3. Dose-limiting toxicity (DLT) consisted of elevation of both total and direct bilirubin ≥ 1.5× baseline in three patients (cohort 1: one of five patients at 50 mg; cohort 2: two of six patients at 100 mg). In cohort 2, one of seven patients had DLT at 75 mg. No DLT was encountered in cohort 3 with 12 patients at 150 mg. Apparent oral clearance (mean ± standard deviation) was cohort dependent as follows: 1.9 ± 0.2 L/h in cohort 1; 3.7 ± 4.7 L/h in cohort 1a; 2.4 ± 1.1 L/h in cohort 2; and 4.5 ± 2.7 L/h in cohort 3 (Kruskal-Wallis, P < .017).

Conclusion

Patients with renal dysfunction tolerate 150 mg of erlotinib daily and seem to have an erlotinib clearance similar to patients without organ dysfunction. Patients with hepatic dysfunction should be treated at a reduced dose (ie, 75 mg daily) consistent with their reduced clearance.
Comparison of Diagnostic Accuracy of Urinary Free Metanephrines, Vanillyl Mandelic Acid, and Catecholamines and Plasma Catecholamines for Diagnosis of Pheochromocytoma
Authors: Boyle James G. , Davidson D. Fraser , Perry Colin G. , Connell John M. C.
Published: July 2007

Context: Recent evidence suggests that plasma-free metanephrines provide a highly sensitive test in patients requiring exclusion of pheochromocytoma. The diagnostic efficacy of urinary free metanephrines, however, has not been evaluated.

Objective, Design, Setting, Patients, and Outcome Measures: We compared retrospectively the diagnostic efficacy of 24-h urinary free metanephrines with our currently available measurements of 24-h urinary vanillyl mandelic acid (VMA), urinary catecholamines, and plasma catecholamines in 159 outpatients tested in a tertiary referral center for pheochromocytoma over a 4-yr period.

Results: The sensitivity of urinary free metanephrines was 100% [25 of 25 patients; 95% confidence interval (CI) 86–100%)] compared with the sensitivity of 84% (21 of 25; 95% CI 64–95%) for urinary catecholamines; 72% (18 of 25; 95% CI 51–88%) for urinary VMA; and 76% (16 of 21; 95% CI 53–92%) for plasma catecholamines. The specificity of urinary free metanephrines was 94% (116 of 123; 95% CI 89–98%), compared with the specificity of 99% (127 of 129; 95% CI 96–100%) for urinary catecholamines; 96% (130 of 134; 95% CI 91–98%) for urinary VMA; and 88% (66 of 75; 95% CI 78–94%) for plasma catecholamines. Receiver operating characteristic curves for all test groups were generated. Pairwise comparisons of the area under the receiver operating characteristic curve for urinary free metanephrines with that of each of the other three test groups individually were: 0.993 (95% CI 0.962–0.999) vs. 0.919 (95% CI 0.862–0.957, P = 0.032) for urine catecholamines; 0.993 (95% CI 0.962–0.999) vs. 0.846 (95% CI 0.778–0.900, P = 0.002) for urine VMA; and 0.992 (95% CI 0.945–0.998) vs. 0.852 (95% CI 0.762–0.918, P = 0.009) for plasma catecholamines. Testing with urinary free metanephrines failed to misidentify a single case of pheochromocytoma, compared with four missed cases for urinary catecholamines, seven missed cases for urinary VMA, and five missed cases for plasma catecholamines.

Conclusion: Urinary free metanephrines were superior to urinary VMA, urinary catecholamines, and plasma catecholamines and can provide a valuable test for diagnosis of pheochromocytoma in adults.
Kisspeptin-54 Stimulates Gonadotropin Release Most Potently during the Preovulatory Phase of the Menstrual Cycle in Women
Authors: Dhillo Waljit S. , Chaudhri Owais B. , Thompson Emily L. , Murphy Kevin G. , Patterson Michael , Ramachandran Radha , Nijher Gurjinder K. , Amber Vian , Kokkinos Alexander , Donaldson Mandy , Ghatei Mohammad A. , Bloom Stephen R.
Published: July 2007

Context: Kisspeptin, the endogenous ligand of the G protein-coupled receptor 54, is a key regulator of the hypothalamo-pituitary-gonadal (HPG) axis. GPR54-null mice exhibit reproductive dysfunction, and exogenous kisspeptin potently stimulates the HPG axis in rodents, primates, and human males. The effects of kisspeptin administration to human females are unknown.

Objective: Our objective was to investigate the effects of kisspeptin on LH release during the menstrual cycle in female volunteers.

Design: Bolus sc kisspeptin-54 was administered to female volunteers, and plasma gonadotropins were measured.

Setting: The study took place at a hospital clinical research facility.

Volunteers: Subjects were healthy female volunteers with regular menstrual cycles.

Intervention: 1) Volunteers received a sc bolus injection of kisspeptin-54 (0, 0.2, 0.4, 0.8, 1.6, 3.2, and 6.4 nmol/kg; n = 3–4 per dose) in the follicular phase; and 2) volunteers (n = 8) received a sc bolus injection of either kisspeptin-54 (0.4 nmol/kg) or saline in random order during each phase of the menstrual cycle.

Main Outcome Measures: Plasma gonadotropins were measured.

Results: 1) Kisspeptin-54 caused a dose-dependent increase in mean LH over time at doses from 0.2–6.4 nmol/kg. 2) Kisspeptin-54 increased plasma LH compared with saline injection in all phases of the cycle. The effect of kisspeptin was greatest in the preovulatory phase and least in the follicular phase of the cycle [mean increase in LH over baseline (IU/liter) ± sem for follicular phase was 0.12 ± 0.17; preovulatory phase, 20.64 ± 2.91 (P < 0.001 vs. follicular phase); luteal phase, 2.17 ± 0.79 (P < 0.01 vs. follicular phase)].

Conclusion: Elevation of plasma kisspeptin in human females potently stimulates LH release in the preovulatory phase and provides a novel mechanism for manipulation of the HPG axis in women.
MafA Regulates Expression of Genes Important to Islet β-Cell Function
Authors: Matsuoka Taka-aki , Kaneto Hideaki , Stein Roland , Miyatsuka Takeshi , Kawamori Dan , Henderson Eva , Kojima Itaru , Matsuhisa Munehide , Hori Masatsugu , Yamasaki Yoshimitsu
Published: July 2007

Insulin transcription factor MafA is unique in being exclusively expressed at the secondary and principal phase of insulin-expressing cell production during pancreas organogenesis and is the only transcriptional activator present exclusively in islet β-cells. Here we show that ectopic expression of MafA is sufficient to induce a small amount of endogenous insulin expression in a variety of non-β-cell lines. Insulin mRNA and protein expression was induced to a much higher level when MafA was provided with two other key insulin activators, pancreatic and duodenal homeobox (PDX-1) and BETA2. Potentiation by PDX-1 and BETA2 was entirely dependent upon MafA, and MafA binding to the insulin enhancer region was increased by PDX-1 and BETA2. Treatment with activin A and hepatocyte growth factor induced even larger amounts of insulin in AR42J pancreatic acinar cells, compared with other non-β endodermal cells. The combination of PDX-1, BETA2, and MafA also induced the expression of other important regulators of islet β-cell activity. These results support a critical role of MafA in islet β-cell function.
Functional Interaction of Hepatic Nuclear Factor-4 and Peroxisome Proliferator-Activated Receptor-γ Coactivator 1α in CYP7A1 Regulation Is Inhibited by a Key Lipogenic Activator, Sterol Regulatory Element-Binding Protein-1c
Authors: Ponugoti Bhaskar , Fang Sungsoon , Kemper Jongsook Kim
Published: July 2007

Insulin inhibits transcription of cholesterol 7α-hydroxylase (Cyp7a1), a key gene in bile acid synthesis, and the hepatic nuclear factor-4 (HNF-4) site in the promoter was identified as a negative insulin response sequence. Using a fasting/feeding protocol in mice and insulin treatment in HepG2 cells, we explored the inhibition mechanisms. Expression of sterol regulatory element-binding protein-1c (SREBP-1c), an insulin-induced lipogenic factor, inversely correlated with Cyp7a1 expression in mouse liver. Interaction of HNF-4 with its coactivator, peroxisome proliferator-activated receptor-γ coactivator 1α (PGC-1α), was observed in livers of fasted mice and was reduced after feeding. Conversely, HNF-4 interaction with SREBP-1c was increased after feeding. In vitro studies suggested that SREBP-1c competed with PGC-1α for direct interaction with the AF2 domain of HNF-4. Reporter assays showed that SREBP-1c, but not of a SREBP-1c mutant lacking the HNF-4 interacting domain, inhibited HNF-4/PGC-1α transactivation of Cyp7a1. SREBP-1c also inhibited PGC-1α-coactivation of estrogen receptor, constitutive androstane receptor, pregnane X receptor, and farnesoid X receptor, implying inhibition of HNF-4 by SREBP-1c could extend to other nuclear receptors. In chromatin immunoprecipitation studies, HNF-4 binding to the promoter was not altered, but PGC-1α was dissociated, SREBP-1c and histone deacetylase-2 (HDAC2) were recruited, and acetylation of histone H3 was decreased upon feeding. Adenovirus-mediated expression of a SREBP-1c dominant-negative mutant, which blocks the interaction of SREBP-1c and HNF-4, partially but significantly reversed the inhibition of Cyp7a1 after feeding. Our data show that SREBP-1c functions as a non-DNA-binding inhibitor and mediates, in part, suppression of Cyp7a1 by blocking functional interaction of HNF-4 and PGC-1α. This mechanism may be relevant to known repression of many other HNF-4 target genes upon feeding.
Miz1 is required for hair follicle structure and hair morphogenesis
Authors: Gebhardt Anneli , Kosan Christian , Herkert Barbara , Möröy Tarik , Lutz Werner , Eilers Martin , Elsässer Hans-Peter
Published: July 2007

Previous work has implicated the Myc-binding transcription factor Miz1 in the control of keratinocyte proliferation and in the cellular response to TGFβ. Miz1 is expressed in basal keratinocytes of the interfollicular epidermis and in hair follicles. Here we have conditionally knocked out the POZ/BTB transactivation domain of Miz1 in keratinocytes using a keratin 14 (K14)-Cre mouse deleter strain. K14Cre+/Miz1lox/lox mice have rough fur as a result of altered hair follicle orientation, irregular hair pigmentation and disturbed hair fiber structure. A regional thickening of the epidermis at the hair funnel orifice was accompanied by suprabasal proliferation, indicating a delayed exit of keratinocytes from the cell cycle. In addition, the catagen of the hair cycle was delayed in K14Cre+/Miz1lox/lox mice and intrafollicular keratinocyte proliferation was increased. In aged K14Cre+/Miz1lox/lox animals, the number of hair follicles remained unchanged but the number of visible hairs, especially of zigzag hairs, was reduced and a pigmentary incontinence into the dermis developed. Our data show that Miz1 is involved in controlling proliferation and differentiation in hair follicles and in hair fiber morphogenesis.
ArabidopsisCAP1 – a key regulator of actin organisation and development
Authors: Deeks Michael J. , Rodrigues Cecília , Dimmock Simon , Ketelaar Tijs , Maciver Sutherland K. , Malhó Rui , Hussey Patrick J.
Published: July 2007

Maintenance of F-actin turnover is essential for plant cell morphogenesis. Actin-binding protein mutants reveal that plants place emphasis on particular aspects of actin biochemistry distinct from animals and fungi. Here we show that mutants in CAP1, an A. thaliana member of the cyclase-associated protein family, display a phenotype that establishes CAP1 as a fundamental facilitator of actin dynamics over a wide range of plant tissues. Plants homozygous for cap1 alleles show a reduction in stature and morphogenetic disruption of multiple cell types. Pollen grains exhibit reduced germination efficiency, and cap1 pollen tubes and root hairs grow at a decreased rate and to a reduced length. Live cell imaging of growing root hairs reveals actin filament disruption and cytoplasmic disorganisation in the tip growth zone. Mutant cap1 alleles also show synthetic phenotypes when combined with mutants of the Arp2/3 complex pathway, which further suggests a contribution of CAP1 to in planta actin dynamics. In yeast, CAP interacts with adenylate cyclase in a Ras signalling cascade; but plants do not have Ras. Surprisingly, cap1 plants show disruption in plant signalling pathways required for co-ordinated organ expansion suggesting that plant CAP has evolved to attain plant-specific signalling functions.
Maintenance of retinal stem cells byAbcg2is regulated by notch signaling
Authors: Bhattacharya Sumitra , Das Ani , Mallya Kavita , Ahmad Iqbal
Published: July 2007

ABCG2 belongs to the ATP-binding cassette superfamily of transmembrane proteins and is ubiquitously expressed in stem cells including those in the developing nervous system. The ability of ABCG2 to preferentially exclude DNA-intercalating dyes is regarded to be the basis for the enrichment of stem cells or progenitors as dyelow side population (SP) cells. However, the role of ABCG2 in neural stem cells remains speculative and poorly understood. Here, we demonstrate using retinal stem cells, that ABCG2 is the molecular determinant of SP cell phenotype of neural stem cells and plays an important role in their maintenance. Overexpression of ABCG2 prevents the SP cell phenotype and adversely affects the lineage commitment of retinal stem cells. By contrast, targeted attenuation of ABCG2 depletes retinal SP cells and promotes their differentiation along pan neural and retinal lineages. In addition, we demonstrate for the first time that ABCG2 is a target of Notch signaling, and as such, constitutes one of the genes in the regulatory network of Notch signaling, involved in the maintenance of stem cells.
An in vivo model of apoptosis: linking cell behaviours and caspase substrates in embryos lacking DIAP1
Authors: Chandraratna Dhianjali , Lawrence Nicola , Welchman David P. , Sanson Bénédicte
Published: July 2007

The apoptotic phenotype is characterised by dynamic changes in cell behaviours such as cell rounding and blebbing, followed by chromatin condensation and cell fragmentation. Whereas the biochemical pathways leading to caspase activation have been actively studied, much less is known about how caspase activity changes cell behaviours during apoptosis. Here, we address this question using early Drosophila melanogaster embryos lacking DIAP1. Reflecting its central role in the inhibition of apoptosis, loss of DIAP1 causes massive caspase activation. We generated DIAP1-depleted embryos by either using homozygous null mutants for thread, the gene coding DIAP1, or by ectopically expressing in early embryos the RGH protein Reaper, which inhibits DIAP1. We show that (1) all cells in embryos lacking DIAP1 follow synchronously the stereotypic temporal sequence of behaviours described for apoptotic mammalian cells and (2) these cell behaviours specifically require caspase activity and are not merely a consequence of cellular stress. Next, we analyse the dynamic changes in the localisation of actomyosin, Discs large, Bazooka and DE-cadherin in the course of apoptosis. We show that early changes in Bazooka and Discs large correlate with early processing of these proteins by caspases. DE-cadherin and Myosin light chain do not appear to be cleaved, but their altered localisation can be explained by cleavage of known regulators. This illustrates how embryos lacking DIAP1 can be used to characterise apoptotic changes in the context of an embryo, thus providing an unprecedented in vivo model in which thousands of cells initiate apoptosis simultaneously.
Diplomates Day 2007
Authors: Eaton Kenneth A
Published: July 2007

On Saturday, 24th February 2007, the Faculty of General Dental Practice (UK) hosted its annual ceremony of the presentation of Diplomates. A total of 101 individuals received Diplomas in a packed Edward Lumley Hall at The Royal College of Surgeons of England.