If a stem cell dies in the crypt, and no one is around to see it….

Two recent studies continue the debate regarding lineage and hierarchy in the intestinal epithelium. One reports that quiescent crypt cells are Paneth cell precursors (Buczacki et al., 2013).

Sox2 marks epithelial competence to generate teeth in mammals and reptiles.

Tooth renewal is initiated from epithelium associated with existing teeth. The development of new teeth requires dental epithelial cells that have competence for tooth formation, but specific marker genes for these cells have not been identified. Here, we analyzed expression patterns of the transcription factor Sox2 in two different modes of successional tooth formation: tooth replacement and serial addition of primary teeth.

Measurement of the dynamical dipolar coupling in a pair of magnetic nanodisks using a ferromagnetic resonance force microscope.

We perform a spectroscopic study of the collective spin-wave dynamics occurring in a pair of magnetic nanodisks coupled by the magnetodipolar interaction. We take advantage of the stray field gradient produced by the magnetic tip of a ferromagnetic resonance force microscope to continuously tune and detune the relative resonance frequencies between two adjacent nano-objects. This reveals the anticrossing and hybridization of the spin-wave modes in the pair.

Lgr5-expressing cells are sufficient and necessary for postnatal mammary gland organogenesis.

Mammary epithelial stem cells are vital to tissue expansion and remodeling during various phases of postnatal mammary development. Basal mammary epithelial cells are enriched in Wnt-responsive cells and can reconstitute cleared mammary fat pads upon transplantation into mice. Lgr5 is a Wnt-regulated target gene and was identified as a major stem cell marker in the small intestine, colon, stomach, and hair follicle, as well as in kidney nephrons.

Label-Free, Longitudinal Visualization of PDT Response In Vitro with Optical Coherence Tomography.

A major challenge in creating and optimizing therapeutics in the fight against cancer is visualizing and understanding the microscale spatiotemporal treatment response dynamics that occur in patients. This is especially true for photodynamic therapy (PDT), where therapeutic optimization relies on understanding the interplay between factors such as photosensitizer localization and uptake, in addition to light dose and delivery rate. In vitro 3D culture systems that recapitulate many of the biological features of human disease are powerful platforms for carrying out detailed studies on PDT response and resistance.

Functional comparison of chronological and in vitro aging: differential role of the cytoskeleton and mitochondria in mesenchymal stromal cells.

Mesenchymal stromal cells (MSCs) are of high relevance for the regeneration of mesenchymal tissues such as bone and cartilage. The promising role of MSCs in cell-based therapies and tissue engineering appears to be limited due to a decline of their regenerative potential with increasing donor age, their limited availability in human tissues and the need of in vitro expansion prior to treatment. We therefore aimed to determine to which degree in vitro aging and chronological aging may be similar processes or if in vitro culture-related changes at the cellular and molecular level are at least altered as a function of donor age.

Summary of the IADR Cariology Research, Craniofacial Biology, and Mineralized Tissue Groups Symposium, Iguaçu Falls, Brazil, June 2012: Gene-environment Interactions and Epigenetics in Oral Diseases: Enamel Formation and its Clinical Impact on Tooth Defects, Caries, and Erosion.

Characteristics of enamel may influence or modulate individual susceptibility to caries and erosion. These characteristics are defined during development, which is under strict genetic control, but can easily be modified in many ways by environmental factors. In the symposium, translational aspects of embryology, biochemistry, and genetics of amelogenesis were presented.

BRAF inhibitor activity in V600R metastatic melanoma.

Activating mutations in the BRAF gene occur in approximately 50% of melanomas. More than 70% of BRAF mutations are V600E and 10-30% are V600K. Potent and selective BRAF inhibitors have demonstrated significant clinical benefits in patients with V600E and V600K BRAF-mutated melanoma.

microRNA miR-34a regulates cytodifferentiation and targets multi-signaling pathways in human dental papilla cells.

Odontogenesis relies on the reciprocal signaling interactions between dental epithelium and neural crest-derived mesenchyme, which is regulated by several signaling pathways. Subtle changes in the activity of these major signaling pathways can have dramatic effects on tooth development. An important regulator of such subtle changes is the fine tuning function of microRNAs (miRNAs).

Injectable bone tissue engineering using expanded mesenchymal stem cells.

Patients suffering from bone defects are often treated with autologous bone transplants, but this therapy can cause many complications. New approaches are therefore needed to improve treatment for bone defects, and stem cell therapy presents an exciting alternative approach. Although extensive evidence from basic studies using stem cells has been reported, few clinical applications using stem cells for bone tissue engineering have been developed.

Fgf8 dosage determines midfacial integration and polarity within the nasal and optic capsules.

Craniofacial development requires an exquisitely timed and positioned cross-talk between the embryonic cephalic epithelia and mesenchyme. This cross-talk underlies the precise translation of patterning processes and information into distinct, appropriate skeletal morphologies. The molecular and cellular dialogue includes communication via secreted signaling molecules, including Fgf8, and effectors of their interpretation.

13-year long-term associations between changes in traditional cardiovascular risk factors and changes in fibrinogen levels: the Coronary Artery Risk Development in Young Adults (CARDIA) study.

Objective: Cross-sectional and prospective studies have linked cardiovascular events and traditional risk factors (TRFs) with higher plasma fibrinogen levels. In a young cohort, we sought to determine longitudinal associations between changes in/development of TRFs and fibrinogen levels over 13 years.

Methods: We included 2525 adults from the CARDIA study, aged 25-37 with fibrinogen and TRFs measured at year 7 (study baseline; 1992-1993); and year 20 (follow-up).

A genome-wide association study identifies susceptibility loci for nonsyndromic sagittal craniosynostosis near BMP2 and within BBS9.

Sagittal craniosynostosis is the most common form of craniosynostosis, affecting approximately one in 5,000 newborns. We conducted, to our knowledge, the first genome-wide association study for nonsyndromic sagittal craniosynostosis (sNSC) using 130 non-Hispanic case-parent trios of European ancestry (NHW). We found robust associations in a 120-kb region downstream of BMP2 flanked by rs1884302 (P = 1.

Flt3 ligand expands CD4+ FoxP3+ regulatory T cells in human subjects.

CD4(+) CD25(+) FoxP3(+) naturally occurring regulatory T (Treg) cells play a crucial role in the maintenance of immune tolerance and in preventing autoimmune pathology. Interventions that expand Treg cells are highly desirable, as they may offer novel treatment options in a variety of autoimmune and transplantation settings. Paralleling previous preclinical studies, we demonstrate here that administration of the hematopoietic growth factor Flt3L to human subjects increases the frequency and absolute number of Treg cells, and reduces the ratio of CD8(+) T cells to Treg cells in the peripheral blood.

Low Hopes, High Expectations: Expectancy Effects and the Replicability of Behavioral Experiments.

This article revisits two classical issues in experimental methodology: experimenter bias and demand characteristics. We report a content analysis of the method section of experiments reported in two psychology journals (Psychological Science and the Journal of Personality and Social Psychology), focusing on aspects of the procedure associated with these two phenomena, such as mention of the presence of the experimenter, suspicion probing, and handling of deception. We note that such information is very often absent, which prevents observers from gauging the extent to which such factors influence the results.

Proteomic profiling of secreted proteins for the hematopoietic support of interleukin-stimulated human umbilical vein endothelial cells.

Human umbilical cord vein endothelial cells (HUVECs) secrete a number of factors that greatly impact the proliferation and differentiation of hematopoietic stem and progenitor cells (HSPCs). These factors remain largely unknown. Here, we report on the most comprehensive proteomic profiling of the HUVEC secretome and identified 827 different secreted proteins.

In vitro optimization of EtNBS-PDT against hypoxic tumor environments with a tiered, high-content, 3D model optical screening platform.

Hypoxia and acidosis are widely recognized as major contributors to the development of treatment resistant cancer. For patients with disseminated metastatic lesions, such as most women with ovarian cancer (OvCa), the progression to treatment resistant disease is almost always fatal. Numerous therapeutic approaches have been developed to eliminate treatment resistant carcinoma, including novel biologic, chemo, radiation, and photodynamic therapy (PDT) regimens.

Craniofacial and dental development in cardio-facio-cutaneous syndrome: the importance of Ras signaling homeostasis.

Cardio-facio-cutaneous syndrome (CFC) is a RASopathy that is characterized by craniofacial, dermatologic, gastrointestinal, ocular, cardiac, and neurologic anomalies. CFC is caused by activating mutations in the Ras/mitogen-activated protein kinase (MAPK) signaling pathway that is downstream of receptor tyrosine kinase (RTK) signaling. RTK signaling is known to play a central role in craniofacial and dental development, but to date, no studies have systematically examined individuals with CFC to define key craniofacial and dental features.

Making death 'good': instructional tales for dying in newspaper accounts of Jade Goody's death.

Facilitating a 'good' death is a central goal for hospices and palliative care organisations. The key features of such a death include an acceptance of death, an open awareness of and communication about death, the settling of practical and interpersonal business, the reduction of suffering and pain, and the enhancement of autonomy, choice and control. Yet deaths are inherently neither good nor bad; they require cultural labour to be 'made over' as good.

Stem cell and biomaterials research in dental tissue engineering and regeneration.

This review summarizes approaches used in tissue engineering and regenerative medicine, with a focus on dental applications. Dental caries and periodontal disease are the most common diseases resulting in tissue loss. To replace or regenerate new tissues, various sources of stem cells have been identified such as somatic stem cells from teeth and peridontium.

Proteomic analysis of midtrimester amniotic fluid to identify novel biomarkers for preterm delivery.

Objective: The aim of this study was to identify possible biomarkers for preterm delivery by analyzing midtrimester amniotic fluid.

Methods: Thirty-two amniotic fluid samples were studied; 16 patients had a spontaneous preterm delivery and 16 patients delivered at term. The proteomic technique consisted of surface-enhanced laser desorption ionization time-of-flight (SELDI-TOF) using different types of solid chromatographic chips (Q10, CM10 and IMAC30).

Bridging the gap on Facebook: assessing intergroup contact and its effects for intergroup relations.

In line with Allport's contact hypothesis, previous research showed that direct intergroup contact can reduce prejudices. However, establishing face-to-face contact is not always feasible. We postulate that Facebook-groups are a setting where direct and observed intergroup contact can develop, reducing prejudices and increasing mutual acceptance.