bluuebunny/crossref_metadata_2025 huggingface dataset:
An Efficient Solvent Free Synthesis of 1,8‐Dioxo‐octahydroxanthene Using p‐Toluene Sulfonic Acid
Authors: Bayat Mohammad , Imanieh Hossien , Hossieni Seyydeh Hajar
Published: November 2009

A simple and efficient method for the synthesis of 1,8‐dioxo‐octahydroxanthene by using p‐toluenesulfonic acid as a catalyst under solvent free conditions is described, which involves cyclization of 2,2‐arylmethylenebis(3‐hydroxy‐5,5‐dimethyl‐2‐cyclohexene‐1‐one) that was obtained firstly by the reaction of dimedone with aromatic aldehydes in water as solvent and catalyst at room temperature. The experimental procedures in the two steps are very simple and the products are formed in excellent yields.
Fluorapatite: An Effective Solid Base Catalyst for Michael Addition of Indole/pyrrole to Nitroalkenes under Solventless Condition
Authors: Zhang Litao , Zhang Lili , Zou Jianping
Published: November 2009

Solid base fluorapatite was found to catalyze the Michael addition of indole/pyrrole to nitroalkenes efficiently under solventless condition, affording the products in good to excellent yields. The Michael addition occurred at the 3‐position of indole exclusively with an exception of 3‐methylindole. The synthetic fluorapatite could be recovered and reused easily without obvious loss in activity.
Stage I nonsmall cell lung cancer in patients aged ≥75 years
Authors: Haasbeek Cornelis J. A. , Lagerwaard Frank J. , Antonisse Marilisa E. , Slotman Ben J. , Senan Suresh
Published: November 2009

BACKGROUND:

The number of patients aged ≥75 years who present with a stage I nonsmall cell lung cancer (NSCLC) is increasing. Elderly patients often have significant comorbidity and may be unfit for surgery. Furthermore, surgery in the elderly is associated with increased mortality and morbidity. In this study, the authors evaluated the outcomes of stereotactic radiotherapy (SRT) in elderly patients.

METHODS:

Since 2003, 203 tumors in 193 patients aged ≥75 years were treated using SRT (118 T1 tumors, 85 T2 tumors). The median patient age was 79 years, 80% of patients were considered medically inoperable, and 20% of patients declined surgery. The median Charlson comorbidity score was 4, and severe chronic obstructive pulmonary disease (Global Initiative for Chronic Obstructive Lung Disease Class III or greater) was present in 25% of patients. Risk‐adapted SRT schemes were used with the same total dose of 60 grays in 3 fractions (33%), 5 fractions (50%), or 8 fractions (17% of patients), depending on the patient's risk for toxicity.

RESULTS:

SRT was well tolerated, and all but 1 patient completed treatment. Survival rates at 1 year and 3 years were 86% and 45%, respectively. Survival was correlated with performance score (P = .001) and pre‐SRT lung function (P = .04). The actuarial local control rate at 3 years was 89%. Acute toxicity was uncommon, and late Radiation Therapy Oncology Group grade ≥3 toxicity was observed in <10% of patients.

CONCLUSIONS:

SRT achieved high local control rates with minimal toxicity in patients aged ≥75 years despite their significant medical comorbidities. These results indicated that more active diagnostic and therapeutic approaches are justified in elderly patients and that SRT should be considered and discussed as a curative treatment alternative. Cancer 2010. © 2010 American Cancer Society.
Mining@home: toward a public‐resource computing framework for distributed data mining
Authors: Lucchese C. , Mastroianni C. , Orlando S. , Talia D.
Published: November 2009

Several classes of scientific and commercial applications require the execution of a large number of independent tasks. One highly successful and low‐cost mechanism for acquiring the necessary computing power for these applications is the ‘public‐resource computing’, or ‘desktop Grid’ paradigm, which exploits the computational power of private computers. So far, this paradigm has not been applied to data mining applications for two main reasons. First, it is not straightforward to decompose a data mining algorithm into truly independent sub‐tasks. Second, the large volume of the involved data makes it difficult to handle the communication costs of a parallel paradigm. This paper introduces a general framework for distributed data mining applications called Mining@home. In particular, we focus on one of the main data mining problems: the extraction of closed frequent itemsets from transactional databases. We show that it is possible to decompose this problem into independent tasks, which however need to share a large volume of the data. We thus introduce a data‐intensive computing network, which adopts a P2P topology based on super peers with caching capabilities, aiming to support the dissemination of large amounts of information. Finally, we evaluate the execution of a pattern extraction task on such network. Copyright © 2009 John Wiley & Sons, Ltd.
A comparison of using Taverna and BPEL in building scientific workflows: the case of caGrid
Authors: Tan Wei , Missier Paolo , Foster Ian , Madduri Ravi , De Roure David , Goble Carole
Published: November 2009

When the emergence of ‘service‐oriented science,’ the need arises to orchestrate multiple services to facilitate scientific investigation—that is, to create ‘science workflows.’ We present here our findings in providing a workflow solution for the caGrid service‐based grid infrastructure. We choose BPEL and Taverna as candidates, and compare their usability in the lifecycle of a scientific workflow, including workflow composition, execution, and result analysis. Our experience shows that BPEL as an imperative language offers a comprehensive set of modeling primitives for workflows of all flavors; whereas Taverna offers a dataflow model and a more compact set of primitives that facilitates dataflow modeling and pipelined execution. We hope that this comparison study not only helps researchers to select a language or tool that meets their specific needs, but also offers some insight into how a workflow language and tool can fulfill the requirement of the scientific community. Copyright © 2009 John Wiley & Sons, Ltd.
Lysosomal degradation of RhoH protein upon antigen receptor activation in T but not B cells
Authors: Schmidt‐Mende Jan , Geering Barbara , Yousefi Shida , Simon Hans‐Uwe
Published: November 2009

RhoH is a member of the Rho (ras homologous) GTPase family, yet it lacks GTPase activity and thus remains in its active conformation. Unlike other Rho GTPases, the RhoH gene transcript is restricted to hematopoietic cells and RhoH was shown to be required for adequate T‐cell activation through the TCR. Here, we demonstrate that both blood T and B cells, but not neutrophils or monocytes, express RhoH protein under physiological conditions. Upon TCR complex activation, RhoH was degraded in lysosomes of primary and Jurkat T cells. Pharmacologic activation of T cells distal to the TCR complex had no effect on RhoH protein levels suggesting that early events during T‐cell activation are required for RhoH protein degradation. In contrast to T cells, activation of the BCR in blood B cells was not associated with changes in RhoH levels. These data suggest that RhoH function might be regulated by lysosomal degradation of RhoH protein following TCR complex but not BCR activation. This newly discovered regulatory pathway of RhoH expression might limit TCR signaling and subsequent T‐cell activation upon Ag contact.
Defective T‐cell receptor‐induced apoptosis of T cells and rejection of transplanted immunogenic tumors in p53−/− mice
Authors: Singh Nagendra , Huang Lei , Qin Haiyan
Published: November 2009

Mice lacking the tumor suppressor gene p53 spontaneously develop T‐cell lymphomas at a high rate, suggesting that in these mice lymphomas arise due to defective apoptosis mechanisms in T cells mediated by p53. However, a role of p53 in regulation of T‐cell responses or apoptosis has been poorly defined. TCR‐mediated signaling in the absence of CD28 costimulation induces both apoptosis and proliferation of naïve T cells from WT mice. In this report we show that, in response to TCR stimulation, T cells from naïve p53‐deficient mice exhibited higher proliferation and drastically reduced apoptosis than WT T cells. CD28 costimulation enhanced the proliferation of TCR‐stimulated WT and p53−/− T cells, suggesting that p53 uncouples CD28‐mediated antiapoptotic and proliferative signals. To evaluate the physiological significance of these findings, we transplanted OVA expressing‐EG.7 tumor cells into WT and p53−/− mice. Unlike WT mice, p53−/− mice exhibited a robust tumor‐resistant phenotype and developed cytotoxic T‐cell responses against OVA. Collectively, these data support the hypothesis that p53 is an essential factor in negative regulation of T‐cell responses and have implication for immunomodulation during treatment of cancers and other inflammatory conditions.
Abnormal CTLA‐4 function in T cells from patients with systemic lupus erythematosus
Authors: Jury Elizabeth C. , Flores‐Borja Fabian , Kalsi Hardeep S. , Lazarus Mark , Isenberg David A. , Mauri Claudia , Ehrenstein Michael R.
Published: November 2009

CTLA‐4 is a critical gatekeeper of T‐cell activation and immunological tolerance and has been implicated in patients with a variety of autoimmune diseases through genetic association. Since T cells from patients with the autoimmune disease systemic lupus erythematosus (SLE) display a characteristic hyperactive phenotype, we investigated the function of CTLA‐4 in SLE. Our results reveal increased CTLA‐4 expression in FOXP3− responder T cells from patients with SLE compared with other autoimmune rheumatic diseases and healthy controls. However, CTLA‐4 was unable to regulate T‐cell proliferation, lipid microdomain formation and phosphorylation of TCR‐ζ following CD3/CD28 co‐stimulation, in contrast to healthy T cells. Although lupus T cells responded in vitro to CD3/CD28 co‐stimulation, there was no parallel increase in CTLA‐4 expression, which would normally provide a break on T‐cell proliferation. These defects were associated with exclusion of CTLA‐4 from lipid microdomains providing an anatomical basis for its loss of function. Collectively our data identify CTLA‐4 dysfunction as a potential cause for abnormal T‐cell activation in patients with SLE, which could be targeted for therapy.
Microrna-30D Promotes Tumor Invasion and Metastasis by Targeting Galphai2 in Hepatocellular Carcinoma
Authors: Yao Jian , Liang Linhui , Huang Shenglin , Ding Jie , Tan Ning , Zhao Yingjun , Yan Mingxia , Ge Chao , Zhang Zhenfeng , Chen Taoyang , Wan Dafang , Yao Ming , Li Jinjun , Gu Jianren , He Xianghuo
Published: November 2009

The pathological relevance and significance of microRNAs (miRNAs) in hepatocarcinogenesis have attracted much attention in recent years; however, little is known about the underlying molecular mechanisms through which miRNAs are involved in the development and progression of hepatocellular carcinoma (HCC). In this study, we demonstrate that miR-30d is frequently up-regulated in HCC and that its expression is highly associated with the intrahepatic metastasis of HCC. Furthermore, the enhanced expression of miR-30d could promote HCC cell migration and invasion

in vitro

and intrahepatic and distal pulmonary metastasis

in vivo

, while silencing its expression resulted in a reduced migration and invasion. Galphai2 (GNAI2) was identified as the direct and functional target of miR-30d with integrated bioinformatics analysis and messenger RNA array assay. This regulation was further confirmed by luciferase reporter assays. In addition, our results, for the first time, showed that GNAI2 was frequently suppressed in HCC by way of quantitative reverse-transcription polymerase chain reaction and immunohistochemical staining assays. The increase of the GNAI2 expression significantly inhibits, whereas knockdown of the GNAI2 expression remarkably enhances HCC cell migration and invasion, indicating that GNAI2 functions as a metastasis suppressor in HCC. The restoration of GNAI2 can inhibit miR-30d–induced HCC cell invasion and metastasis.

Conclusion:

The newly identified miR-30d/GNAI2 axis elucidates the molecular mechanism of HCC cell invasion and metastasis and represents a new potential therapeutic target for HCC treatment. (Hepatology 2010.)
Active versus passive teaching styles: An empirical study of student learning outcomes
Authors: Michel Norbert , Cater John James , Varela Otmar
Published: December 2009

This study compares the impact of an active teaching approach and a traditional (or passive) teaching style on student cognitive outcomes. Across two sections of an introductory business course, one class was taught in an active or “nontraditional” manner, with a variety of active learning exercises. The second class was taught in a passive or “traditional” manner, emphasizing daily lectures. Although the active learning approach does not appear to have improved overall mastery of the subject, we did find evidence that active learning can lead to improved cognitive outcomes in class‐specific materials. The discussion emphasizes the role of delivery style on learning outcomes.
Paving the way for groundwater management: Transforming information for crafting management rules
Authors: Hammani Ali , Hartani Tarik , Kuper Marcel , Imache Amar
Published: November 2009

In many countries, farmers are turning to groundwater to make up for surface water scarcity and to deal with increasing water demand, even inside large‐scale irrigation schemes. In many situations, this leads to the mining of groundwater resources, which in turn threatens the sustainability of the farms that depend on this resource. The purpose of this study was to find ways to provide the necessary information to stakeholders to enable them to construct rules for sustainable groundwater management. The dynamics of water resources and water use practices were analysed and management indicators were designed for two irrigation schemes in North Africa: Tadla (Morocco) and Mitidja West (Algeria). The results showed, firstly, that available groundwater has decreased; secondly, that farming systems depend to an increasing extent on groundwater resources, and thirdly, that individual and collective access to groundwater depends on informal arrangements. We developed and tested a platform for dialogue for water management focused on exploring plausible scenarios of agricultural development in relation to the use of groundwater. Copyright © 2009 John Wiley & Sons, Ltd.
Salinity patterns in irrigation systems, a threat to be demystified, a constraint to be managed: Field evidence from Algeria and Tunisia
Authors: Bouarfa S. , Marlet S. , Douaoui A. , Hartani T. , Mekki I. , Ghazouani W. , Aissa I. Ben , Vincent B. , Hassani F. , Kuper M.
Published: November 2009

Salinity problems induced by irrigation are often presented in the literature as a threat that can only be managed at the irrigation scheme scale by installing subsurface drainage. On the other hand, salinity is a constraint that has often been successfully managed locally by farmers adapting their practices. However, the continuing expansion of irrigation with related water scarcity problems plus the increasing use of groundwater of marginal quality has resulted in a new challenge that is difficult to handle at the farm level only. To assess the dynamics of soil salinity and water quality together with farmers' salinity management practices, we adapted a common approach to analyze two contrasted salinity patterns: a traditional salinity pattern in an oasis (Fatnassa, Tunisia), and a recent sodicity pattern in a large irrigation scheme (Lower Chelif, Algeria). This approach which combines surveys on farmers' perceptions and practices and salinity measurements and geochemical analysis paves the way for more integrated management of salinity problems related to water scarcity. Copyright © 2009 John Wiley & Sons, Ltd.
Linking water saving and productivity to agro‐food supply chains: A synthesis from two North African cases
Authors: Le Gal P.‐Y. , Kuper M. , Moulin C.‐H. , Sraïri M. T. , Rhouma A.
Published: November 2009

The relationship between irrigated schemes, farms and agro‐food processors may provide leeway to improve water saving and water productivity. This study was conducted in the dairy supply area of the Tadla irrigation scheme in Morocco and in the oasis area in southern Tunisia where dates are grown for export. The study was based on (i) a framework conceptualizing the relationship between production/marketing of agricultural raw material and water saving and productivity and (ii) a participatory research method aimed at supporting stakeholders in solving their production problems. Analysis of the organization of the two supply chains revealed the central role of intermediate operators in aggregating raw material and providing services to farmers. A decision support approach for dairy farmers was designed and tested in the Tadla scheme. Its use is illustrated by four scenarios that simulate the impacts of changes in both forage crops and irrigation techniques on farm income and water consumption and productivity. Lessons drawn from this work concern support for stakeholders and the integration of production functions from the irrigated scheme to the agro‐processors in the whole supply chain. Copyright © 2009 John Wiley & Sons, Ltd.
Mechanism of increased PLD1 gene expression during early adipocyte differentiation process of mouse cell line 3T3‐L1
Authors: Gao Siqiang , Ito Hiromi , Murakami Masashi , Yoshida Kayo , Tagawa Yoko , Hagiwara Kazumi , Takagi Akira , Kojima Tetsuhito , Suzuki Motoshi , Banno Yoshiko , Ohguchi Kenji , Nozawa Yoshinori , Murate Takashi
Published: November 2009

A mouse cell line 3T3‐L1 is differentiated into adipocytes when treated with an inducer cocktail (IDX) (insulin, dexametahsone, and a cAMP phosphodiesterase inhibitor of isobutyl‐methylxanthine (IBMX)). Here, we report that PLD1, but not PLD2, mRNA and protein increased during the early differentiation process. Our analysis shows that IDX resulted in a sequential induction of C/EBPβ, PLD1, and C/EBPα which is a key transcription factor of late adipocyte differentiation. Among the three inducers, IBMX + any other inducer induced mild adipocyte differentiation, whereas insulin + dexamethasone did not. IBMX increased PLD1 but not PLD2 mRNA. Forskolin, an adenylate cyclase activator, and dbcAMP also increased PLD1 mRNA, suggesting the cellular cAMP as the inducer of both adipocyte differentiation and PLD1 transcription. We focused on the regulatory mechanism of PLD1 transcription during this differentiation process. IDX or a combination of inducers including IBMX increased PLD1 promoter activity, which is consistent with mRNA analysis. Promoter analysis identified two adjacent C/EBP motifs located between −338 and −231 bp from the first exon as the IBMX responsive elements. Furthermore, overexpression of C/EBPβ, but not C/EBPα, increased PLD1 mRNA and PLD1 5′ promoter activity. EMSA and chromatin immunoprecipitation assay confirmed the direct binding of C/EBPβ, but not C/EBPα, to these C/EBP motifs of PLD1 5′ promoter. Our results show that PLD1 is a target gene of C/EBPβ through the increased cellular cAMP during early adipocyte differentiation of 3T3‐L1 cells. J. Cell. Biochem. 109: 375–382, 2010. © 2009 Wiley‐Liss, Inc.
The control of fracture healing and its therapeutic targeting: Improving upon nature
Authors: Komatsu David E. , Warden Stuart J.
Published: November 2009

Fracture repair is a complex process involving timed cellular recruitment, gene expression, and synthesis of compounds that regenerate native tissue to restore the mechanical integrity, and thus function of injured bone. While the majority of fractures heal without complication, this takes time and a subset of patients (∼10%) experience healing delays, extending their morbidity and treatment costs. Consequently, there is a need for efficacious therapeutics for the intervention of fracture healing. Recent studies into the molecular control of fracture repair and advances in the understanding of the skeleton as a whole have resulted in the identification of numerous novel targets and compounds for such intervention. These include traditional agents such bone morphogenetic proteins and other growth factors, but also relatively newer compounds such as parathyroid hormone and modulators of the Wnt signaling pathway. These agents, along with others, are discussed in the current article in terms of their investigative status and potential for clinical implementation. Hopefully, these agents, as well as others yet to be discovered, will demonstrate sufficient clinical utility for successful intervention of fracture healing. This may have significant implications for the duration of morbidity and costs associated with traumatic bone fractures. J. Cell. Biochem. 109: 302–311, 2010. © 2009 Wiley‐Liss, Inc.
Structural basis of integrin transmembrane activation
Authors: Wang Wei , Luo Bing‐Hao
Published: November 2009

Integrins are cell adhesion receptors that transmit bidirectional signals across plasma membrane and are crucial for many biological functions. Recent structural studies of integrin transmembrane (TM) and cytoplasmic domains have shed light on their conformational changes during integrin activation. A structure of the resting state was solved based on Rosetta computational modeling and experimental data using intact integrins on mammalian cell surface. In this structure, the αIIb GXXXG motif and their β3 counterparts of the TM domains associate with ridge‐in‐groove packing, and the αIIb GFFKR motif and the β3 Lys‐716 in the cytoplasmic segments play a critical role in the α/β association. Comparing this structure with the NMR structures of the monomeric αIIb and β3 (represented as active conformations), the α subunit helix remains similar after dissociation whereas β subunit helix is tilted by embedding additional 5–6 residues into the lipid bilayer. These conformational changes are critical for integrin activation and signaling across the plasma membrane. We thus propose a new model of integrin TM activation in which the recent NMR structure of the αIIbβ3 TM/cytoplasmic complex represents an intermediate or transient state, and the electrostatic interaction in the cytoplasmic region is important for priming the initial α/β association, but not absolutely necessary for the resting state. J. Cell. Biochem. 109: 447–452, 2010. © 2009 Wiley‐Liss, Inc.
Surfing the wave, cycle, life history, and genes/proteins expressed by testicular germ cells. Part 1: Background to spermatogenesis, spermatogonia, and spermatocytes
Authors: Hermo Louis , Pelletier R.‐Marc , Cyr Daniel G. , Smith Charles E.
Published: November 2009

Spermatogenesis, a study of germ cell development, is a long, orderly, and well‐defined process occurring in seminiferous tubules of the testis. It is a temporal event whereby undifferentiated spermatogonial germ cells evolve into maturing spermatozoa over a period of several weeks. Spermatogenesis is characterized by three specific functional phases: proliferation, meiosis, and differentiation, and it involves spermatogonia, spermatocytes, and spermatids. Germ cells at steps of development form various cellular associations or stages, with 6, 12, and 14 specific stages being identified in human, mouse, and rat, respectively. The stages evolve over time in a given area of the seminiferous tubule forming a cycle of the seminiferous epithelium that has a well‐defined duration for a given species. In this part, we discuss the proliferation and meiotic phase whereby spermatogonia undergo several mitotic divisions to form spermatocytes that undergo two meiotic divisions to form haploid spermatids. In the rat, spermatogonia can be subdivided into several classes: stem cells (As), proliferating cells (Apr, Aal), and differentiating cells (A1–A4, In, B). They are dependent on a specific microenvironment (niche) contributed by Sertoli, myoid, and Leydig cells for proper development. Spermatogonia possess several surface markers whereby they can be identified from each other. During meiosis, spermatocytes undergo chromosomal pairing, synapsis, and genetic exchange as well as transforming into haploid cells following meiosis. The meiotic cells form specific structural entities such as the synaptonemal complex and sex body. Many genes involved in spermatogonial renewal and the meiotic process have been identified and shown to be essential for this event. Microsc. Res. Tech., 2010. © 2009 Wiley‐Liss, Inc.
Surfing the wave, cycle, life history, and genes/proteins expressed by testicular germ cells. Part 3: Developmental changes in spermatid flagellum and cytoplasmic droplet and interaction of sperm with the zona pellucida and egg plasma membrane
Authors: Hermo Louis , Pelletier R.‐Marc , Cyr Daniel G. , Smith Charles E.
Published: November 2009

Spermiogenesis constitutes the steps involved in the metamorphosis of spermatids into spermatozoa. It involves modification of several organelles in addition to the formation of several structures including the flagellum and cytoplasmic droplet. The flagellum is composed of a neck region and middle, principal, and end pieces. The axoneme composed of nine outer microtubular doublets circularly arranged to form a cylinder around a central pair of microtubules is present throughout the flagellum. The middle and principal pieces each contain specific components such as the mitochondrial sheath and fibrous sheath, respectively, while outer dense fibers are common to both. A plethora of proteins are constituents of each of these structures, with each playing key roles in functions related to the fertility of spermatozoa. At the end of spermiogenesis, a portion of spermatid cytoplasm remains associated with the released spermatozoa, referred to as the cytoplasmic droplet. The latter has as its main feature Golgi saccules, which appear to modify the plasma membrane of spermatozoa as they move down the epididymal duct and hence may be partly involved in male gamete maturation. The end product of spermatogenesis is highly streamlined and motile spermatozoa having a condensed nucleus equipped with an acrosome. Spermatozoa move through the female reproductive tract and eventually penetrate the zona pellucida and bind to the egg plasma membrane. Many proteins have been implicated in the process of fertilization as well as a plethora of proteins involved in the development of spermatids and sperm, and these are high lighted in this review. Microsc. Res. Tech., 2010. © 2009 Wiley‐Liss, Inc.
Surfing the wave, cycle, life history, and genes/proteins expressed by testicular germ cells. Part 4: Intercellular bridges, mitochondria, nuclear envelope, apoptosis, ubiquitination, membrane/voltage‐gated channels, methylation/acetylation, and transcription factors
Authors: Hermo Louis , Pelletier R.‐Marc , Cyr Daniel G. , Smith Charles E.
Published: November 2009

As germ cells divide and differentiate from spermatogonia to spermatozoa, they share a number of structural and functional features that are common to all generations of germ cells and these features are discussed herein. Germ cells are linked to one another by large intercellular bridges which serve to move molecules and even large organelles from the cytoplasm of one cell to another. Mitochondria take on different shapes and features and topographical arrangements to accommodate their specific needs during spermatogenesis. The nuclear envelope and pore complex also undergo extensive modifications concomitant with the development of germ cell generations. Apoptosis is an event that is normally triggered by germ cells and involves many proteins. It occurs to limit the germ cell pool and acts as a quality control mechanism. The ubiquitin pathway comprises enzymes that ubiquitinate as well as deubiquitinate target proteins and this pathway is present and functional in germ cells. Germ cells express many proteins involved in water balance and pH control as well as voltage‐gated ion channel movement. In the nucleus, proteins undergo epigenetic modifications which include methylation, acetylation, and phosphorylation, with each of these modifications signaling changes in chromatin structure. Germ cells contain specialized transcription complexes that coordinate the differentiation program of spermatogenesis, and there are many male germ cell‐specific differences in the components of this machinery. All of the above features of germ cells will be discussed along with the specific proteins/genes and abnormalities to fertility related to each topic. Microsc. Res. Tech., 2010. © 2009 Wiley‐Liss, Inc.
Surfing the wave, cycle, life history, and genes/proteins expressed by testicular germ cells. Part 5: Intercellular junctions and contacts between germs cells and Sertoli cells and their regulatory interactions, testicular cholesterol, and genes/proteins associated with more than one germ cell generation
Authors: Hermo Louis , Pelletier R.‐Marc , Cyr Daniel G. , Smith Charles E.
Published: November 2009

In the testis, cell adhesion and junctional molecules permit specific interactions and intracellular communication between germ and Sertoli cells and apposed Sertoli cells. Among the many adhesion family of proteins, NCAM, nectin and nectin‐like, catenins, and cadherens will be discussed, along with gap junctions between germ and Sertoli cells and the many members of the connexin family. The blood‐testis barrier separates the haploid spermatids from blood borne elements. In the barrier, the intercellular junctions consist of many proteins such as occludin, tricellulin, and claudins. Changes in the expression of cell adhesion molecules are also an essential part of the mechanism that allows germ cells to move from the basal compartment of the seminiferous tubule to the adluminal compartment thus crossing the blood‐testis barrier and well‐defined proteins have been shown to assist in this process. Several structural components show interactions between germ cells to Sertoli cells such as the ectoplasmic specialization which are more closely related to Sertoli cells and tubulobulbar complexes that are processes of elongating spermatids embedded into Sertoli cells. Germ cells also modify several Sertoli functions and this also appears to be the case for residual bodies. Cholesterol plays a significant role during spermatogenesis and is essential for germ cell development. Lastly, we list genes/proteins that are expressed not only in any one specific generation of germ cells but across more than one generation. Microsc. Res. Tech., 2010. © 2009 Wiley‐Liss, Inc.
Surfing the wave, cycle, life history, and genes/proteins expressed by testicular germ cells. Part 2: Changes in spermatid organelles associated with development of spermatozoa
Authors: Hermo Louis , Pelletier R.‐Marc , Cyr Daniel G. , Smith Charles E.
Published: November 2009

Spermiogenesis is a long process whereby haploid spermatids derived from the meiotic divisions of spermatocytes undergo metamorphosis into spermatozoa. It is subdivided into distinct steps with 19 being identified in rats, 16 in mouse and 8 in humans. Spermiogenesis extends over 22.7 days in rats and 21.6 days in humans. In this part, we review several key events that take place during the development of spermatids from a structural and functional point of view. During early spermiogenesis, the Golgi apparatus forms the acrosome, a lysosome‐like membrane bound organelle involved in fertilization. The endoplasmic reticulum undergoes several topographical and structural modifications including the formation of the radial body and annulate lamellae. The chromatoid body is fully developed and undergoes structural and functional modifications at this time. It is suspected to be involved in RNA storing and processing. The shape of the spermatid head undergoes extensive structural changes that are species‐specific, and the nuclear chromatin becomes compacted to accommodate the stream‐lined appearance of the sperm head. Microtubules become organized to form a curtain or manchette that associates with spermatids at specific steps of their development. It is involved in maintenance of the sperm head shape and trafficking of proteins in the spermatid cytoplasm. During spermiogenesis, many genes/proteins have been implicated in the diverse dynamic events occurring at this time of development of germ cells and the absence of some of these have been shown to result in subfertility or infertility. Microsc. Res. Tech., 2010. © 2009 Wiley‐Liss, Inc.
Evaluation of the smear layer and hybrid layer in noncarious and carious dentin prepared by air abrasion system and diamond tips
Authors: Oliveira Ana Carolina Mascarenhas , Lima Luciana Monti , Pizzolitto Antônio Carlos , Santos‐Pinto Lourdes
Published: November 2009

Purpose:

To analyze the smear layer and the hybrid layer in noncarious and carious dentin prepared by different cutting instruments and restored with composite resin.

Study design:

Cavities were randomly prepared in 160 specimens (noncarious and artificial carious dentin) by high‐speed diamond tips (KG Sorensen 1013), air abrasion system (Prepstart, Danville Engineering), ultrasonic tip (CVDentus 8.3231‐1), and ultrasonic tip associated with ultrasonic cavitation by water for 10 s. Half of the cavities in each group were conditioned with 37% phosphoric acid for 15 s. The amount of smear layer and dentinal tubules present were analyzed using scanning electron microscopy and graded from 0 to 3. Cavities were prepared in another 20 noncarious specimens and 20 carious specimens and restored with adhesive composite resin system. The restorations were hemisected longitudinally and analyzed using scanning electron microscopy to evaluate the hybrid layer and resinous prolongation characteristics, using scores ranging from 1 to 6.

Results:

The data were statistically analyzed using Kruskal‐Wallis and Dunn tests at 5% of significance level. There was evidence that the most efficient smear layer removal was the acid etching in the noncarious dentin and the water ultrasonic cavitation in the carious dentin. The hybrid layer formed on the noncarious and carious dentin prepared by the ultrasonic tip was more regular than in the specimens prepared by high‐speed diamond tip, with many resinous prolongations.

Conclusion:

The ultrasonic tip seems to be a promising tool for carious dentin cavity preparation. Microsc. Res. Tech., 2010. © 2009 Wiley‐Liss, Inc.
MRT letter: Auto‐fluorescence by human alveolar macrophages after in vitro exposure to air pollution particles
Authors: Ghio Andrew J. , Sangani Rahul G. , Brighton Luisa E. , Carson John L.
Published: November 2009

Macrophages from smokers demonstrate an increased auto‐fluorescence. Similarly, auto‐fluorescence follows in vitro exposure of macrophages to cigarette smoke condensate (i.e., the particulate fraction of cigarette smoke). The composition of particles in cigarette smoke can be comparable to air pollution particles. We tested the postulate that macrophages exposed to air pollution particles could demonstrate auto‐fluorescence. Healthy nonsmoking and healthy smoking volunteers (both 18–40 years of age) underwent fiberoptic bronchoscopy with bronchoalveolar lavage and alveolar macrophages isolated. Macrophages were incubated at 37°C in 5% CO2 with either PBS or 100 μg/mL particle for both 1 and 24 h. Particles included a residual oil fly ash, Mt. St. Helens volcanic ash, and ambient air particles collected from St. Louis, Missouri and Salt Lake City, Utah. At the end of incubation, 50 μL of the cell suspension was cytocentrifuged and examined at modes for viewing fluorescein isothiocyanate (FITC) and rhodamine fluorescence. Both emission source air pollution particles demonstrated FITC and rhodamine auto‐fluorescence at 1 and 24 h, but the signal following incubation of the macrophages with oil fly ash appeared greater. Similarly, the ambient particles were associated with auto‐fluorescence by the alveolar macrophages and this appeared to be dose‐dependent. We conclude that exposure of macrophages to air pollution particles can be associated with auto‐fluorescence in the FITC and rhodamine modes. Microsc. Res. Tech., 2010. © 2009 Wiley‐Liss, Inc.
A new bone vascular perfusion compound for the simultaneous analysis of bone and vasculature
Authors: Sider Krista L. , Song Janice , Davies John E.
Published: November 2009

Bone is a highly vascular tissue, which plays an important role in bone development and healing. The ability to analyze both the bone and vasculature simultaneously can enhance the understanding of wound healing, development, and disease in bone. At present, analysis methods are limited in their ability to allow for this simultaneous analysis of bone and bone vasculature in three dimensions, without using the most recent dual‐energy computed tomography (CT) techniques. In this study, we present a new barium sulfate (BaSO4) radiopaque vascular perfusion compound for performing postmortem microangiography with single‐beam microcomputed tomography (microCT), which allows for such simultaneous analysis. This compound differs from currently available contrast mediums due to (1) the high weight‐to‐volume ratio of BaSO4achieved, (2) small BaSO4aggregate size (<5 μm), (3) minimal additives, and (4) its miscibility with blood and saline. Most notably, it achieves a radiodensity of 2.4× that of cortical bone, with high perfusion of both the arterial and venous systems and the intervening capillary bed, resulting in an in vivo radiodensity that ranges from that of bone to titanium. Our results, verified using a rat femoral gap‐healing model, show that the compound is uniquely suited to high‐contrast imaging of the vasculature in the presence of undecalcified bone, with a versatility to be used in other tissues. Microsc. Res. Tech., 2010. © 2009 Wiley‐Liss, Inc.
Oogenesis and programmed cell death of nurse cells in the endoparasitoid, Pteromalus puparum
Authors: Dong Sheng‐Zhang , Ye Gong‐Yin , Guo Jian‐Yang , Yu Xiao‐Ping , Hu Cui
Published: November 2009

In this study, we describe the features of oogenesis in the endoparasitoid, Pteromalus puparum, as well as the distinct type of programmed cell death of the nurse cells through conventional light and fluorescent markers for apoptosis and immunofluorescent analysis. Oogenesis in this endoparasitoid is divided into five stages, of which stages 1–2, 3–4, and 5 are corresponding to previtellogenic growth, yolk uptake, and the formation of egg envelopes, respectively. From these studies, we demonstrate two critical events, which are vitellogenin absorption and rapid transfer of nurse cell content, resulting in remarkable increase in the volume of oocytes during oogenesis in this endoparasitoid. Vitellogenin absorption initiates in the oocyte of early stage 3, and bulk transfer of nurse cell content into the oocyte occurs at stage 4 of oogenesis in P. puparum, which is mainly characterized with the programmed cell death in the nurse cell complex. Microsc. Res. Tech., 2010. © 2009 Wiley‐Liss, Inc.
Mirror lenses in light microscopy—Theoretical considerations and practical implications
Authors: Piper Jörg
Published: November 2009

Various types of mirror lenses were developed some decades ago designed for several special tasks in microscopy. When compared with high‐end glass lenses, mirror lenses lead to an extraordinary image quality because of their supraapochromatic color fidelity and their high planarity; the working distances are significantly longer, and in most cases, the depth of field and resolution are higher than in concurrent glass lenses. In this respect, the microscopic advantages of mirror lenses seem to be comparable with the advantages of mirror telescopes in astronomy; for in observations of celestial bodies, mirror telescopes lead to better results than refractors based on glass lenses. When mirror lenses are available in light microscopy, not only common illumination modes can be carried out in transmitted or incident light, but also new and specific axial illumination techniques can be utilized, which cannot be achieved with normal glass lenses. This axial illumination, called “luminance contrast,” can be carried out in various modes, so that the resulting images can be compared with dark‐field, phase or interference‐contrast images. In all variants, especially, fine details within transparent specimens can be visible in maximized contrast and resolution, and blooming or haloing artifacts are significantly reduced or absent. These findings are based on theoretical consideration, and intensive practical tests carried out with several mirror lenses constructed in various optical designs. All in all, supramicroscopic image qualities could be expected if mirror lenses were produced based on the optimized manufacturing techniques available nowadays. Microsc. Res. Tech. 2010. © 2009 Wiley‐Liss, Inc.
Extensive human cytomegalovirus (HCMV) genomic DNA in the renal tubular epithelium early after renal transplantation: Relationship with HCMV DNAemia and long‐term graft function
Authors: Li Ying Ting , Emery Vincent C. , Surah Saloni , Jarmulowicz Michael , Sweny Paul , Kidd I. Michael , Griffiths Paul D. , Clark Duncan A.
Published: November 2009

Human cytomegalovirus (HCMV) infection is associated with a series of direct and indirect effects following renal transplantation. However, the presence of HCMV in the kidney and its relationship with acute rejection and long‐term graft function remain to be fully elucidated. Sixty‐two biopsies derived from 30 renal transplant recipients with signs of clinical rejection were analyzed for HCMV using a sensitive in situ DNA hybridization method. Biopsies were also subjected to staining with anti‐C4d antibodies and an anti‐caspase 3 antibody to detect humoral rejection and apoptosis, respectively. In 21 patients, serial serum creatinine levels over 5 years of follow‐up were analyzed. HCMV DNA was detected in biopsies from 21/30 (70%) of the patients and 32/62 (52%) of the individual biopsies. HCMV DNA was detected early after transplant and was localized to renal tubule epithelial cells but not associated with apoptosis. HCMV DNAemia developed within 2 weeks of detecting HCMV DNA in the biopsy in 53% of patients. Ninety percent of patients experiencing HCMV disease had HCMV DNA in their biopsy. HCMV DNA was equally distributed between patients with or without histological evidence of acute rejection and was detected more frequently in patients with peritubular C4d deposits. Creatinine levels at 12 months post‐transplant were significantly higher in patients with HCMV DNA and remained elevated over the 5 years of follow‐up. HCMV DNA is frequently detected in renal tubular epithelial cells early after renal transplantation, precedes DNAemia and is associated with poor long‐term graft function. J. Med. Virol. 82:85–93, 2010. © 2009 Wiley‐Liss, Inc.
Sex matters in the establishment of murine tendon composition and material properties during growth
Authors: Mikic Borjana , Amadei Elizabeth , Rossmeier Kerri , Bierwert LouAnn
Published: November 2009

The existence of sex‐based differences in tendon and ligament injury rates has led investigators to test the hypothesis that sex plays a significant role in modulating tendon and ligament composition and material properties. To date, no studies have attempted to characterize how such differences develop during the course of normal tissue maturation and growth. Thus, the primary aim of the present study was to use a murine model to test the hypothesis that sex‐based differences in the normal age‐related development of tendon composition and material properties exist by assessing these parameters in the Achilles and tail tendons from 4‐, 6‐, 9‐, 12‐, and 15‐week‐old male and female C57Bl/6J mice. Despite significantly lower levels of total collagen content in females subsequent to sexual maturity (p < 0.0001), as well as a significant effect of sex on glycosaminoglycan content (p < 0.0001), Achilles tendon elastic modulus was not compromised in females. Female Achilles tendons did exhibit a significantly higher failure strain (p = 0.0201) and strain energy density (p = 0.0004) than did males, as well as a trend toward higher ultimate strength (p = 0.0556). In contrast to the high load‐bearing environment of the Achilles tendon site, sex did not have a statistically significant effect on any compositional or material property in the low load‐bearing tendon fascicles of the tail. These data support recent studies by others, which suggest that male and female tendons have a differential adaptational response to their local mechanical loading environment. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:631–638, 2010
A multiproxy record of late Holocene natural and anthropogenic environmental change from the Sphagnum peat bog Dürres Maar, Germany: implications for quantitative climate reconstructions based on pollen
Authors: Kühl Norbert , Moschen Robert , Wagner Stefanie , Brewer Simon , Peyron Odile
Published: November 2009

Pollen data are well established for quantitative climate reconstructions over long timescales, including the Holocene and older interglacials. However, anthropogenically induced environmental change in central Europe was strong during the last 4 ka, challenging quantitative reconstructions of this time period. Here we present quantitative climate reconstructions based on pollen analyses and evaluate them with the peat humification record and the stable carbon isotopes of Sphagnum plant material (δ13Ccellulose). All analyses were carried out on the same 7.5 m long, largely ombrotrophic peat bog section from Dürres Maar. Three different methods were used for the quantitative climate reconstructions on the basis of the pollen data: (1) a probabilistic indicator taxa approach (the ‘pdf method’); (2) a modern analogue technique based on pollen taxa from modern surface samples (cMAT); and (3) a modern analogue technique expanded by plant functional types (pMAT). At Dürres Maar the peat humification is only affected by peat cutting during the Roman period and the Middle Ages. The stable carbon isotopes are seemingly unaffected by human impact. Thus both proxies provide independent data to evaluate the reconstructions on the basis of pollen data. The quantitative climate reconstructions on the basis of the individual methods are in general relatively similar. Nevertheless, distinct differences between the individual approaches are also apparent, which could be attributed to taxa that reflect human impact on a local to regional scale. While the pdf method appears to be relatively robust to all observed anthropogenically induced vegetation changes, it potentially underestimates climate variability. This method is therefore expected to be independent of local site characteristics and to provide robust quantitative estimates of climatic trends rather than of climatic variability of small amplitude. This is of value for palaeoclimate reconstructions of older interglacials, for which neither multiple sites nor independent climate proxies are available for comparison. Copyright © 2009 John Wiley & Sons, Ltd.
Preparative isolation of neomangiferin and mangiferin from Rhizoma anemarrhenae by high‐speed countercurrent chromatography using ionic liquids as a two‐phase solvent system modifier
Authors: Xu Lili , Li Aifeng , Sun Ailing , Liu Renmin
Published: November 2009

A preparative high‐speed countercurrent chromatography method for isolation and purification of neomangiferin and mangiferin from Rhizoma anemarrhenae was successfully established by using ionic liquids as the modifier of the two‐phase solvent system. Neomangiferin and mangiferin were purified from the crude extract of R. anemarrhenae by using ethyl acetate‐water‐[C4mim][PF6] (5:5:0.2 v/v) as two‐phase solvent system. In total, 22.5 mg of neomangiferin and 70.6 mg of mangiferin were obtained from 150 mg of the crude extract. The purities of neomangiferin and mangiferin were 97.2 and 98.1%, respectively, as determined by HPLC. The chemical structures of the isolated compounds were identified by 1H‐NMR and 13C‐NMR.