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The article focuses on the growing concerns about the integrity of scientific research worldwide, particularly regarding the handling of errors and retractions in published papers. Retraction Watch provides a valuable service by promptly highlighting challenges to recent publications, covering topics such as self-plagiarism, data manipulation, and mismanaged research studies.

This review identifies some key concepts of muscle regeneration, viewed from perspectives of classical and modern research. Early insights noted the pattern and sequence of regeneration across species was similar, regardless of the type of injury, and differed from epimorphic limb regeneration. While potential benefits of exercise for tissue repair was debated, regeneration was not presumed to deliver functional restoration, especially after ischemia–reperfusion injury; muscle could develop fibrosis and ectopic bone and fat. Standard protocols and tools were identified as necessary for tracking injury and outcomes. Current concepts vastly extend early insights. Myogenic regeneration occurs within the environment of muscle tissue. Intercellular cross-talk generates an interactive system of cellular networks that with the extracellular matrix and local, regional, and systemic influences, forms the larger gestalt of the satellite cell niche. Regenerative potential and adaptive plasticity are overlain by epigenetically regionalized responsiveness and contributions by myogenic, endothelial, and fibroadipogenic progenitors and inflammatory and metabolic processes. Muscle architecture is a living portrait of functional regulatory hierarchies, while cellular dynamics, physical activity, and muscle–tendon–bone biomechanics arbitrate regeneration. The scope of ongoing research—from molecules and exosomes to morphology and physiology—reveals compelling new concepts in muscle regeneration that will guide future discoveries for use in application to fitness, rehabilitation, and disease prevention and treatment. [ABSTRACT FROM AUTHOR]

A fortuitous auroral storm and a clear dark sky in a rural prairie setting allowed the authors to observe a Strong Thermal Emission Velocity Enhancement (aka STEVE) on a warm March night. It was a night of marvelous sights and new discovery. [ABSTRACT FROM AUTHOR]

The article focuses on the EngageAI Institute, originally the National Science Foundation AI Institute for Engaged Learning, designed for educators interested in using AI to enhance teaching skills. Topics include ethical considerations in artificial intelligence (AI)-augmented learning, a focus on STEM education for grades K–12, and efforts to increase participation among under-represented groups, such as women, people of color, and persons with disabilities.

The article focuses on the practical implementation of ethics in web design, providing a structured framework that moves beyond theoretical considerations. Topics include the need for ethical considerations in today's web design environment, an organized approach based on ethical theories, and a checklist of questions for designers to evaluate the impact of their decisions on both the designer and the end user.

The article focuses on artists suing artificial intelligence (AI) companies Midjourney and Stable Diffusion, alleging "industrial-level identity theft" for using their creative works without credit or compensation to train image-generating AI. It explores the ethical challenges posed by AI in creative fields, raising questions about derivative works, identity theft, and the management of recognition for original artists, cautioning readers about the broader implications of AI in culture.

The article focuses on importance of intellectual freedom to unleash creativity and discovery. Topics discussed include knowledge gained and the ideas of others to create even greater possibilities of insight and invention; financial supporters expect integrity in the process and unbiased results; and creativity and freedom to pursue even unpopular subjects are hampered.

The author comments on critical librarianship and how it interplays with intellectual freedom. Topics covered include impact of activism on the goal of the library to promote social consciousness, how the social activism of librarians affect their responsibility toward intellectual freedom, possible alienation of community members and library users due to social activism of librarians and the importance for librarians to respect the choices and ideology of individuals.

ABSTRACT Current research on skeletal muscle injury and regeneration highlights the crucial role of nerve-muscle interaction in the restoration of innervation during that process. Activities of muscle satellite or stem cells, recognized as the 'currency' of myogenic repair, have a pivotal role in these events, as shown by ongoing research. More recent investigation of myogenic signalling events reveals intriguing roles for semaphorin3A (Sema3A), secreted by activated satellite cells, in the muscle environment during development and regeneration. For example, Sema3A makes important contributions to regulating the formation of blood vessels, balancing bone formation and bone remodelling, and inflammation, and was recently implicated in the establishment of fibre-type distribution through effects on myosin heavy chain gene expression. This review highlights the active or potential contributions of satellite-cell-derived Sema3A to regulation of the processes of motor neurite ingrowth into a regenerating muscle bed. Successful restoration of functional innervation during muscle repair is essential; this review emphasizes the integrative role of satellite-cell biology in the progressive coordination of adaptive cellular and tissue responses during the injury-repair process in voluntary muscle. [ABSTRACT FROM AUTHOR]

The author argues that searching for information or products on the Internet has a censoring impact. Google, Bing, and Yahoo are cited as examples of major search engines. According to the author, private information are used by search engines to help screen or filter information. Also mentioned are the possibility of bias, use of recommendation technologies with the discovery software, and the information professional's responsibility in minimizing the censoring impact.

There is an acknowledged gap between the theory presented in university preparation programmes and the reality of classroom practice that has resulted in many secondary mathematics pre-service teachers failing to implement university-endorsed teaching strategies. Using responses to a questionnaire and interviews, this qualitative study examined the factors that support or inhibit secondary mathematics pre-service teachers’ implementation of problem-solving tasks during professional experience. The results showed that even though the majority of pre-service teachers reported having beliefs compatible with using problem-solving tasks, the secondary students’ ability, preparation time, and the cooperating teacher were key factors that inhibited pre-service teachers’ implementation of problem-solving tasks. It is recommended that pre-service teachers regularly visit classrooms to observe the evolving implementation of problem-solving approaches. Furthermore, cooperating teachers should be required to attend professional development before the professional experience so they understand the goals of the university preparation programme and have the requisite skills and knowledge to support the implementation of problem-solving tasks in learning mathematics. [ABSTRACT FROM AUTHOR]

The article offers the author's insights on privacy and the significance of personal data collection. Topics discussed include the use of Internet, confidentiality and control of information, and personal information marketing. She mentions that open network of information has become a product dispersing machine and economic data collection.

Satellite cells (SCs), stem cells in skeletal muscle, are mitotically quiescent in adult mammals until activated for growth or regeneration. In mouse muscle, SCs are activated by nitric oxide (NO), hepatocyte growth factor (HGF) and the mechanically induced NO-HGF signaling cascade. Here, the SC population on fibers from the adult, ectothermic zebrafish and SC responsiveness to activating stimuli were assessed using the model system of isolated fibers cultured at 27 and 21°C. SCs were identified by immunostaining for the HGF receptor, c-met, and activation was determined using bromodeoxyuridine uptake in culture or in vivo. In dose-response studies, SC activation was increased by treatment with the NO-donor drug isosorbide dinitrate (1 mmol l-1) or HGF (10 ng ml-1) to maximum activation at lower concentrations of both than in previous studies of mouse fibers. HGF-induced activation was blocked by anti-c-met antibody, and reduced by culture at 21°C. The effect of cyclical stretch (3 h at 4 cycles per minute) increased activation and was blocked by nitric oxide synthase inhibition and reduced by culture at 21°C. The number of c-met+ SCs per fiber increased rapidly (by 3 h) after stretching. The character of signaling in SC activation on zebrafish fibers, in particular temperature-dependent responses to HGF and stretch, gives new insights into the influence of ectothermy on regulation of muscle growth in teleosts and suggests the use of the single-fiber model system to explore the basis of fiber hyperplasia and the conservation of regulatory pathways between species. [ABSTRACT FROM AUTHOR]

Satellite cells (SC), stem cells in skeletal muscle, are mitotically quiescent in adult mammals until activated for growth or regeneration. In mouse muscle, SC are activated by nitric oxide (NO), hepatocyte growth factor (HGF) and the mechanically induced NO-HGF signaling cascade. Here, the SC population on fibers from the adult, ectothermic zebrafish and SC responsiveness to activating stimuli were assessed using the model system of isolated fibers cultured at 27°C and 21°C. SC were identified by immunostaining for the HGF receptor, c-met, and activation was determined using bromodeoxyuridine uptake in culture or in vivo. In dose-response studies, SC activation was increased by treatment with the NO-donor drug isosorbide dinitrate (1mM) or HGF (10 ng/mL) to maximum activation at lower and higher concentrations, respectively, than in previous studies of mouse fibers. HGF-induced activation was blocked by anti-c-met antibody, and reduced by culture at 21°C. The effect of cyclical stretch (3 hr at 4 cycles per min) increased activation and was blocked by NOS inhibition and reduced by culture at 21°C. The number of c-met+ SC/fiber increased rapidly (by 3 hr) after stretching. The character of signaling in SC activation on zebrafish fibers, in particular temperature-dependent responses to HGF and stretch gives new insights into the influence of ectothermy on regulation of muscle growth in teleosts and suggests use of the single-fiber model system to explore the basis of fiber hyperplasia and the conservation of regulatory pathways between species. [ABSTRACT FROM AUTHOR]

Highlights: [•] The lack of dystrophin in mdx mice impacts electrophysiology of Purkinje neurons. [•] Purkinje neurons from mdx mice showed reduced spontaneous action potential firing. [•] Intrinsic membrane properties of Purkinje neurons differ between cerebellar regions. [•] Results stress the need to consider cerebellar region in studies of Purkinje neurons. [Copyright &y& Elsevier]

Abusive head trauma, formerly known as shaken baby syndrome, is a condition with physical, psychosocial, and fiscal implications presenting opportunities for nurses to intervene with prevention strategies. This integrative review of the literature explored the empirical evidence to identify prevention strategies effective in decreasing abusive head trauma. Education, medical, and nursing databases yielded 14 quality research studies providing the basis for the review. Multiple facets of prevention strategies were identified with patterns in the literature of community involvement, early detection and involvement by health professionals, and parental education programming. A five-component model of prevention strategies is proposed to provide nurses with a comprehensive approach to the issue. These components consist of a) completion of personal inventory, b) involvement in multi-modal parental education, c) commitment to a prevention program, d) participation of the family and community, and e) connection to a spiritual element. Through these components, it is hoped there is enhancement of the quality of life for parents and infants, and a discouragement of situations that increase the risk of infant injury. [ABSTRACT FROM AUTHOR]

In universities where standards-based assessment is advocated, common practice involves organising written descriptions of criteria and standards in marking guides to ensure greater consistency in marking. Marking guides are often also distributed to students prior to assessment to scaffold their learning. However, research shows that many students find written descriptions of standards difficult to understand, and even when students use a marking guide to mark short assignment exemplars, they rate the exemplars more useful and use them more than the marking guide in completing their assignment. In this qualitative study, we use a constructivist framework to explore students’ perceptions of their experience of participating in marking, and student- and teacher-led discussion of essay exemplars in class. Students found the marking guide useful for marking the essays but thought that the exemplars and the teacher’s explanation together provided them with a clearer understanding of expected standards. The ‘marking class’ prompted students to reflect on the quality of their future work. The implication for teachers is that marking guides are helpful to students only when students use them to critically evaluate exemplars. To help students understand what constitutes good quality work, teachers need to allocate class time to explaining their grading decisions. [ABSTRACT FROM AUTHOR]

Highlights: [•] Duchenne muscular dystrophy (DMD) has a central nervous system component. [•] Intellectual and cognitive abilities are often impacted in DMD. [•] Boys with DMD tend to display verbal memory deficits and executive dysfunction. [•] Depression and difficulties with social interactions are often present in DMD. [•] Comorbid conditions include autism spectrum and obsessive-compulsive disorders. [Copyright &y& Elsevier]

Changes in attitude toward intellectual property are covered here. [ABSTRACT FROM AUTHOR]

Prompted by international concerns about school and postschool participation in mathematics, the authors of the present study sought to investigate factors predicting "switching on" and "switching off" in mathematics, operationalized through measures of future intent and disengagement, respectively. They drew from Bronfenbrenner's ecological model to explore an educational ecology comprising student, home, classroom, school, and time factors in predicting future intent and disengagement. These models were conducted within a multilevel context, thereby also assessing variation at student, classroom, and school levels. Based on data from 1,601 Australian middle school students from 200 classrooms in 44 schools, variance components models showed the bulk of variance (> 85%) in future intent and disengagement resided at the student (and residual) level, with 10%-12% variance explained at classroom and school levels. Multilevel hierarchical regression analyses revealed that student, home, and classroom factors explained most variance in dependent measures. For future intent and disengagement, mathematics self-efficacy, valuing, enjoyment, perceived classroom enjoyment, and parent interest were significant predictors. For disengagement, additional predictors were mathematics anxiety, perceived classroom disengagement, school ethnic composition, and school socioeconomic status. Modeling indicated all predictive effects generalized across classrooms and schools. Findings hold implications for the breadth and depth of efforts in mathematics aimed at reducing disengagement, increasing participation, and promoting more positive future orientations through school and beyond. [ABSTRACT FROM AUTHOR]

Abstract: Age-related muscle atrophy or sarcopenia results in progressive loss of muscle function and satellite cells in aging muscle are increasingly refractory to activation that could mitigate atrophy. We know that nitric oxide release triggered by mechanical stretch of skeletal muscle, initiates satellite cell activation in vitro in single fiber, single cell and whole-muscle cultures, and in vivo in animals. This study examined muscle cell activation using tritiated-thymidine incorporation into the DNA of muscle cells in cultured muscles from female mice between 6 weeks and 18 months-of-age. Experiments examined age-related changes in activation by mechanical stretch and/or NO treatments (with the substrate of nitric oxide synthase (l-arginine), a nitric oxide donor (isosorbide dinitrate) and/or nitric oxide synthase inhibition). Activation without stretch was highest at 8 months. Stretching muscles by 10% more than doubled activation in muscles at 6 weeks of age and only a 20% stretch similarly activated cells in cultured 6-month-old muscles. Only treatment with ISDN in combination with a 20% stretch activated cell proliferation in muscles from 8-month-old mice. A nitric-oxide donor drug rescued muscle satellite cells in adult, 8-month-old mice from being refractory to mechanical stretch, apparently by overcoming an ineffective release of nitric oxide during stretch. Results suggest that treatment with nitric oxide has the potential to enhance the effectiveness of exercise in preventing the onset of age-related muscle atrophy in adult muscle. [Copyright &y& Elsevier]

The article discusses the importance of using the National Assessment Program for Literacy and Numeracy (NAPLAN) items to develop students' thinking skills in Australia. It mentions that using the said items, students will be taught to adopt new problem-solving strategies, build confidence and resilience, and develop number sense. It recommends that teachers may use the NAPLAN items as discussion starters if they are pressured of preparing their students for the tests as to promote thinking.

To attain a superior in vitro model of mature muscle fibers, we modified the established protocol for isolating single muscle fibers from rat skeletal muscle. Muscle fiber cultures with high viability were obtained using flexor digitorum brevis muscle and lasted for at least 7 days. We compared the expression levels of adult myosin heavy chain (MyHC) isoforms in these single muscle fibers with myotubes formed from myoblasts; isolated fibers contained markedly more abundant adult MyHC isoforms than myotubes. This muscle fiber model, therefore, will be useful for studying the various functions and cellular processes of mature muscles in vitro. [ABSTRACT FROM AUTHOR]

Context: The modified Thomas test is commonly used in the clinical setting to assess flexibility about the thigh region. Objective: To evaluate the clinical reliability of the modified Thomas test for evaluating the flexibility of the rectus femoris muscle about the knee joint. Design: Descriptive laboratory study using a test-retest design. Setting: Institution-based clinical orthopaedic setting. Patients or Other Participants: Fifty-seven individuals between the ages of 18 and 45 years with no history of trauma participated. Of those, 54 completed the study. Intervention(s): Three Board-certified athletic therapists with an average of 12.67 years of sport medicine expertise assessed rectus femoris flexibility using pass/fail and goniometer scoring systems. A retest session was completed 7 to 10 days later. Main Outcome Measure(s): Parametric and nonparametric tests were used to compare participants' test-retest results. Results: Chance-corrected κ values (intrarater x¯ = 0.40, 95% confidence interval [CI] = 0.30, 0.54; interrater x¯ = 0.33, 95% Cl = 0.23, 0.41) indicated generally poor levels of reliability for pass/fail scoring. Intraclass correlation coefficient (ICC) values (intrarater x¯ = 0.67, 95% Cl = 0.55, 0.76; interrater x¯ = 0.50, 95% Cl = 0.40, 0.60) indicated fair to moderate levels of reliability for goniometer data. Measurement error values (standard error of measurement = 7°, method error = 6°, and coefficient of variation = 13%) and Bland-Altman plots (with 95% limits of agreement) further demonstrated the degree of intrarater variance for each examiner when conducting the test. Conclusions: These results call into question the statistical reliability of the modified Thomas test and provide clinicians with important information regarding its reliability limits when used to clinically assess flexibility of the rectus femoris muscle about the knee joint in a physically active population. More research is needed to ascertain the variables that may confound the statistical reliability of this orthopaedic technique. [ABSTRACT FROM AUTHOR]

Use of cyclooxygenase (COX) inhibitors to delay preterm birth is complicated by in utero constriction of the ductus arteriosus and delayed postnatal closure. Delayed postnatal closure has been attributed to loss of vasa vasorum flow and ductus wall ischemia resulting from constriction in utero. We used the murine ductus (which does not depend on vasa vasorum flow) to determine whether delayed postnatal closure may be because of mechanisms independent of in utero constriction. Acute inhibition of both COX isoforms constricted the fetal ductus on days 18 and 19 (term) but not earlier in gestation; COX-2 inhibition constricted the fetal ductus more than COX-1 inhibition. In contrast, mice exposed to prolonged inhibition of COX-1, COX-2, or both COX isoforms (starting on day 15, when the ductus does not respond to the inhibitors) had no contractile response to the inhibitors on days 18 or 19. Newborn mice closed their ductus within 4 h of birth. Prolonged COX inhibition on days 11-14 of gestation had no effect on newborn ductal closure; however, prolonged COX inhibition on days 15-19 resulted in delayed ductus closure despite exposure to 80% oxygen after birth. Similarly, targeted deletion of COX-2 alone, or COX-1/COX-2 together, impaired postnatal ductus closure. Nitric oxide inhibition did not prevent the delay in ductus closure. These data show that impaired postnatal ductus closure is not the result of in utero ductus constriction or upregulation of nitric oxide synthesis. They are consistent with a novel role for prostaglandins in ductus arteriosus contractile development. [ABSTRACT FROM AUTHOR]

Satellite cells are companions to voluntary muscle fibres, and are named for their intimate positional or 'satellite' relationship, as if revolving around fibres, like a satellite moon around the earth. Studies on the nature of at least some satellite cells, including their capabilities for self-renewal and for giving rise to multiple lineages in a stem cell-like function, are exploring the molecular basis of phenotypes described by markers of specialized function and gene expression in normal development, neuromuscular disease and aging. In adult skeletal muscle, the self-renewing capacity of satellite cells contributes to muscle growth, adaptation and regeneration. Muscle remodeling, such as demonstrated by changes in myofibre cross-sectional area and length, nerve and tendon junctions, and fibre-type distribution, occur in the absence of injury and provide broad functional and structural diversity among skeletal muscles. Those contributions to plasticity involve the satellite cell in at least five distinct roles, here described using metaphors for behaviour or the investigator's perspective. Satellite cells are the 'currency' of muscle; have a 'conveyance' role in adaptation by domains of cytoplasm along a myofibre; serve researchers, through a marker role, as 'clues' to various activities of muscle; are 'connectors' that physically, and through signalling and cell-fibre communications, bridge myofibres to the intra- and extra-muscular environment; and are equipped as metabolic and genetic filters or 'colanders' that can rectify or modulate particular signals. While all these roles are still under exploration, each contributes to the plasticity of skeletal muscle and thence to the overall biology and function of an organism. The use of metaphor for describing these roles helps to clarify and scrutinize the definitions that form the basis of our understanding of satellite cell biology: the metaphors provide the construct for various approaches to detect or test the nature of satellite cell functions in skeletal muscle plasticity. [ABSTRACT FROM AUTHOR]

Knowledge of the events underlying satellite cell activation and the counterpart maintenance of quiescence is essential for planning therapies that will promote the growth and regeneration of skeletal muscle in healthy, disease and aging. By modeling those events of satellite cell activation in studies of single muscle fibers or muscles in culture, the roles of mechanical stretching and nitric oxide are becoming understood. Recent studies demonstrated that stretch-induced activation is very rapid and exhibits some features of satellite cell heterogeneity. As well, gene expression studies showed that expression of the c-met receptor gene rises rapidly after stretching muscles in culture compared to those without stretch. This change in gene expression during activation, and the maintenance of quiescence in both normal and dystrophic muscles are dependent on NO, as they are blocked by inhibition of nitric oxide synthase (NOS). Mechanical, contractile activity is the defining feature of muscle function. Therefore, ongoing studies of stretch effects in satellite cell activation and quiescence in quiescent fiber and muscle cultures provides appropriate models by which to explore the regulatory steps in muscle in vivo under many conditions related to disease, repair, rehabilitation, growth and the prevention or treatment of atrophy. [ABSTRACT FROM AUTHOR]

Satellite cells, muscle precursor cells in skeletal muscle, are normally quiescent and become activated by disease or injury. A lack of dystrophin and changes in the expression or activity of neuronal nitric oxide synthase (NOS-I) affect the timing of activation in vivo. Nitric oxide synthase inhibition delays muscle repair in normal mice, and worsens muscular dystrophy in the mdx mouse, a genetic homologue of Duchenne muscular dystrophy. However, the potential role of activation and repair events mediated by nitric oxide in determining the outcome of steroid or other treatments for muscular dystrophy is not clear. We tested the hypothesis that the extent of repair in dystrophic muscles of mdx mice is partly dependent on NOS-Iμ expression and activity. Myotube formation in regenerating muscle was promoted by deflazacort treatment of mdx dystrophic mice (P<0.05), and improved by combination with the nitric oxide synthase substrate, l-arginine, especially in the diaphragm. NOS-Iμ mRNA expression and activity were present in satellite cells and very new myotubes of regenerating and dystrophic muscle. Deflazacort treatment resulted in increased NOS-Iμ expression in regenerating muscles in a strong and specific correlation with myf5 expression (r=0.95, P<0.01), a marker for muscle repair. Nitric oxide synthase inhibition prevented the deflazacort-induced rise in NOS-Iμ and myf5 expression in the diaphragm without affecting the diameter of non-regenerating fibres. These in vivo studies suggest that gains in NOS-Iμ expression and nitric oxide synthase activity in satellite cells can increase the extent and speed of repair, even in the absence of dystrophin in muscle fibres. NOS-Iμ may be a useful therapeutic target to augment the effects of steroidal or other treatments of muscular dystrophy. [Copyright &y& Elsevier]

Transition issues faced by the sickle cell patient who has a significant chronic illness or disability are many and often life threatening. The problems that are faced in transitioning from Medicaid to managed care are many that could hinder the process and patient satisfaction. Such problems during the transition periods could stem from interrupted health care services; improperly coordinated services; inappropriate intervention; and inappropriate or unfounded psychologically diagnosed cases (Blum, 1993). It is not known which health care programs are cost-effective and which are not. Nor is it known which health care program best meets the needs of patients with chronic illnesses or varying levels of severity; and it is not known if health status actually improves as a result of transitioning from one program to another. What factors then impact the satisfaction levels in transitioning from Medicaid to managed care for sickle cell patients in Hampton Roads, Virginia? This study looked at patient satisfaction with the transition from Medicaid to managed care as related to the cost of care, quality of care, and access to care. [ABSTRACT FROM PUBLISHER]

Transition issues faced by the sickle cell patient who has a significant chronic illness or disability are many and often life threatening. The problems that are faced in transitioning from Medicaid to managed care are many that could hinder the process and patient satisfaction. Such problems during the transition periods could stem from interrupted health care services; improperly coordinated services; inappropriate intervention; and inappropriate or unfounded psychologically diagnosed cases (Blum, 1993). It is not known which health care programs are cost-effective and which are not. Nor is it known which health care program best meets the needs of patients with chronic illnesses or varying levels of severity; and it is not known if health status actually improves as a result of transitioning from one program to another. What factors then impact the satisfaction levels in transitioning from Medicaid to managed care for sickle cell patients in Hampton Roads, Virginia? This study looked at patient satisfaction with the transition from Medicaid to managed care as related to the cost of care, quality of care, and access to care. [ABSTRACT FROM AUTHOR]

Satellite stem cell activation is the process by which quiescent precursor cells resident on muscle fibers are recruited to cycle and move. Two processes are reported to affect satellite cell activation. In vivo, nitric oxide (NO) produced by NO synthase in fibers (NOS-Iμ) promotes activation. In cell cultures, hepatocyte growth factor (HGF) is the major activating factor isolated from crushed muscle extract (CME). In this study we hypothesized that distinct and possibly related events were mediated by NO and HGF during activation. Intact fibers were cultured in the presence of bromodeoxyuridine (BrdU) to label DNA synthesis over 48 h. Experiments were designed to test the effects of CME, HGF, a NOS substrate l-arginine, and the NOS inhibitor l-NAME on activation, determined as the number of BrdU-positive satellite cells per fiber. Activation was increased significantly by CME, HGF, and l-arginine. l-Arginine increased activation in a dose–response manner. CME-induced activation was reduced significantly by NOS inhibition. Exposure to marcaine (10 min) caused reversible membrane damage without hypercontraction, as shown by characterizing the sarcolemmal integrity. The resulting decrease in satellite cell activation could be overcome by exogenous HGF. Results support the hypothesis that NO is involved in recruiting to cycle those satellite cells resident on fibers. Separate assessments of resident and free muscle cells showed that HGF and NO also participate in mobilizing satellite cells. Since HGF counteracted NOS inhibition and marcaine-induced membrane damage, data suggest that NO may mediate early steps in activation and precede HGF-mediated events. [Copyright &y& Elsevier]

Analyzes the data from the survey of the online search techniques of several undergraduate and graduate students at Hayden Library in Arizona State University. Types of user online searches; Use of library personnel and online helpscreens; Exposure to library instruction; Length of time at the terminal for citation versus abstract products; Searching as the most prevalent.

Examines whether a restrictive intake of water and/or ethanol, as well as food, would lower mouse body weight gains and show lowered ethyl carbamate (EC)-induced tumorigenesis comparable to the wine-treated animals. Mean weight gain and food intake of mice fed wine; Incidence and frequency of liver tumors of mice fed wine and EC for 41 weeks.

The Internet opens a wide range of possibilities for accessing materials from both traditional sources and more volatile areas-personal homepages, e-mail and discussion groups archives. Though the role of reference librarians to find the most relevant information for our users seems monumental in this medium, it is an area that needs the objective, ethical expertise of the librarian and archivist. In this 50th year of remembrance of the Holocaust, the Internet is especially active with information on that historic tragedy. Excerpts from accounts by one Hungarian and one Norwegian political prisoner interned in the camps are included as illustrations of material which may not have been found using more traditional research tools. [ABSTRACT FROM PUBLISHER]

The article reports on the release of the National Mathematics Curriculum Framing Paper on February 28, 2009 in Australia. A contextual summary of the framing paper is presented. It says that the key element of national curriculum reforms to improve academic performance is the framing papers, which call for implementation and determination of teachers' and students' needs. Professor Peter Sullivan says that access to all mathematics until Year 9 is the key to success.

The article discusses various issues concerning the role of grants in business development in the modern world. It is informed that grants have become a massive industry. According to the National Council of Non-Profit Associations, the number of non-profit organizations grew 68% between 1993 to 2003 in the United States. Money creates obligations for both the recipient and the grantor. In the past, the number of organizations involved in the grant process was fairly stable. Today, the time has changed, many organizations are relying on grant funding for their growth.

The activity of satellite cells during myogenesis, development, or skeletal muscle regeneration is strongly modelled using cultures of single muscle fibers. However, there are variations in reported features of gene or protein expression as examined with single-fiber cultures. Here, we examined the potential differences in activation of satellite cells on normal mouse muscle fibers produced during a standard isolation protocol, with or without agitation during collagenase digestion. Activation was detected in satellite cells on fibers after 24 and 48 h of culture in basal growth medium using immunodetection of the incorporation of bromodeoxyuridine (BrdU) into DNA and quantification of the number of BrdU-positive cells per fiber. After 24 and 48 h in culture under nonactivating conditions, the number of activated (BrdU+) satellite cells was greater on fibers that had received gentle agitation during collagenase digestion than on those that were subject to digestion without agitation during isolation. The findings are interpreted to mean that at least some of the variation among published reports may derive from the application of various methods of fiber isolation. The information should be useful for maintaining satellite cell quiescence during studies of the regulatory steps that lead to satellite cell activation. [ABSTRACT FROM AUTHOR]

Using a copper-catalyzed coupling reaction of amino acid and aryl halide, followed by intramolecular cyclization of N-aryl-1-hydroxyl-3-propylamines under the Swern’s condition as the key steps, (S)-2-hydroxymethyl-1,2,3,4-tetrahydroquinoline was synthesized as an example of optically pure 2-functionalized 1,2,3,4-tetrahydroquinolines. [Copyright &y& Elsevier]

Mechanical perturbation triggers activation of resident myogenic stem cells to enter the cell cycle through a cascade of events including hepatocyte growth factor (HGF) release from its extracellular tethering and the subsequent presentation to signaling‐receptor c‐met. Here, we show that with aging, extracellular HGF undergoes tyrosine‐residue (Y) nitration and loses c‐met binding, thereby disturbing muscle homeostasis. Biochemical studies demonstrated that nitration/dysfunction is specific to HGF among other major growth factors and is characterized by its locations at Y198 and Y250 in c‐met‐binding domains. Direct‐immunofluorescence microscopy of lower hind limb muscles from three age groups of rat, provided direct in vivo evidence for age‐related increases in nitration of ECM‐bound HGF, preferentially stained for anti‐nitrated Y198 and Y250‐HGF mAbs (raised in‐house) in fast IIa and IIx myofibers. Overall, findings highlight inhibitory impacts of HGF nitration on myogenic stem cell dynamics, pioneering a cogent discussion for better understanding age‐related muscle atrophy and impaired regeneration with fibrosis (including sarcopenia and frailty). [ABSTRACT FROM AUTHOR]

Cell migration is central to development, wound healing, tissue regeneration, and immunity. Despite extensive knowledge of muscle regeneration, myoblast migration during regeneration is not well understood. C2C12 mouse myoblast migration and morphology were investigated using a triple-docking polydimethylsiloxane-based microfluidic device in which cells moved under gravity-driven laminar flow on uniform () collagen (CN), fibronectin (FN), or opposing gradients (CN-FN or FN-CN). In haptotaxis experiments, migration was faster on FN than on CN. At 10 h, cells were more elongated on FN-CN and migration was faster than on the CN-FN substrate. Net migration distance on FN-CN at 10 h was greater than on CN-FN, as cells rapidly entered the channel as a larger population (bulk-cell movement, wave 1). Hepatocyte growth factor (HGF) stimulated rapid chemotaxis on FN but not CN, increasing migration speed at 10 h early in the channel at low HGF in a steep HGF gradient. HGF accelerated migration on FN and bulk-cell movement on both uniform substrates. An HGF gradient also slowed cells in wave 2 moving on FN-CN, not CN-FN. Both opposing-gradient substrates affected the shape, speed, and net distance of migrating cells. Gradient and uniform configurations of HGF and substrate differentially influenced migration behavior. Therefore, haptotaxis substrate configuration potently modifies myoblast chemotaxis by HGF. Innovative microfluidic experiments advance our understanding of intricate complexities of myoblast migration. Findings can be leveraged to engineer muscle-tissue volumes for transplantation after serious injury. New analytical approaches may generate broader insights into cell migration.. [ABSTRACT FROM AUTHOR]

Comments on the findings of study in Caenorhabditis elegans indicating that genetic defects in acetylcholine (AchE) transmission at the neuromuscular junction (NMJ) might partially underlie Duchenne Muscular Dystrophy (DMD). Identification of mutations in the dystrophin gene as the cause of DMD; Reduction in AchE activity in dys-1 mutants; Relevance of cholinergic transmission at the NMJ in mammalian dystrophies.