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Gas–liquid membrane contactors are a promising alternative to packed columns that suffer from channeling, bubble formation, and flooding problems. In this study, potassium serinate + piperazine (PSZ) and potassium alaninate + piperazine (PAZ), which are amino acid salts with good CO 2 absorption performances and high surface tensions, are investigated to determine the effects of the operating parameters on the CO 2 removal efficiency, CO 2 absorption flux, CO 2 loading, and overall mass-transfer coefficient in the membrane contactor process. The experimental results demonstrate that the 2.5 M PSZ and 2.5 M PAZ absorbents outperform 2.5 M monoethanolamine (MEA) under various operating conditions, including the gas flow rate, liquid flow rate, CO 2 concentration, and CO 2 -loaded absorbent. Based on these results, an expression for predicting the CO 2 loading from the pH is proposed. The amount of cross-over confirmed that amino acids with high surface tension have better resistance to membrane wetting than 2.5 M MEA. In addition, empirical correlation expressions were established from the results of several operating parameters. The absolute average deviation (AAD) values were 6.50 %, 2.95 %, and 4.71 % for 2.5 M MEA, 2.5 M PSZ, and 2.5 M PAZ, respectively, suggesting good agreement between the theoretical and experimental results. [Display omitted] • Amino acid salt-based absorbents were applied in a membrane contactor. • Various operating parameters were examined during the membrane contactor process. • Cross-over was measured to explain membrane wetting. • Expression for predicting CO 2 loading from pH is proposed. • Empirical correlation equation for CO 2 removal efficiency is established. [ABSTRACT FROM AUTHOR]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ydbio.2007.09.050 Byline: Seung O. Ko (a)(b), Il Hyuk Chung (a), Xun Xu (a), Shoji Oka (a), Hu Zhao (a), Eui Sic Cho (c), Chuxia Deng (d), Yang Chai (a) Keywords: TGF-[beta]; Smad4; Tooth; Cranial neural crest cells Abstract: Smad4 is the central mediator for TGF-[beta]/BMP signals, which are involved in regulating cranial neural crest (CNC) cell formation, migration, proliferation and fate determination. It is unclear whether TGF-[beta]/BMP signals utilize Smad-dependent or -independent pathways to control the development of CNC cells. To investigate the functional significance of Smad4 in regulating CNC cells, we generated mice with neural crest specific inactivation of the Smad4 gene. Our study shows that Smad4 is not required for the migration of CNC cells, but is required in neural crest cells for the development of the cardiac outflow tract. Smad4 is essential in mediating BMP signaling in the CNC-derived ectomesenchyme during early stages of tooth development because conditional inactivation of Smad4 in neural crest derived cells results in incisor and molar development arrested at the dental lamina stage. Furthermore, Smad-mediated TGF-[beta]/BMP signaling controls the homeobox gene patterning of oral/aboral and proximal/distal domains within the first branchial arch. At the cellular level, a Smad4-mediated downstream target gene(s) is required for the survival of CNC cells in the proximal domain of the first branchial arch. Smad4 mutant mice show underdevelopment of the first branchial arch and midline fusion defects. Taken together, our data show that TGF-[beta]/BMP signals rely on Smad-dependent pathways in the ectomesenchyme to mediate epithelial-mesenchymal interactions that control craniofacial organogenesis. Author Affiliation: (a) Center for Craniofacial Molecular Biology School of Dentistry University of Southern California, 2250 Alcazar Street, CSA 103, Los Angeles, CA 90033, USA (b) Department of Oral and Maxillofacial Surgery, School of Dentistry, Chonbuk National University, Jeonju 561-756, Republic of Korea (c) Laboratory for Craniofacial Biology, Institute of Oral Bioscience, Chonbuk National University, Jeonju 561-756, Republic of Korea (d) Genetics of Development and Disease Branch, NIDDK, National Institutes of Health, Building 10, Room 9N105, Bethesda, MD 20892, USA Article History: Received 1 June 2007; Revised 12 September 2007; Accepted 24 September 2007

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ydbio.2005.09.024 Byline: Qingru Wang, Yu Lan, Eui-Sic Cho, Kathleen M. Maltby, Rulang Jiang Keywords: Adrenal gland; Atrial septum; Heart development; Intermediate mesoderm; Kidney development; Odd-skipped; Osr1; Renal agenesis; Venous valve Abstract: The Odd-skipped related 1 (Odd1) gene encodes a zinc finger protein homologous to the Drosophila Odd-skipped class transcription factors that play critical roles in embryonic patterning and tissue morphogenesis. We have generated mice carrying a targeted null mutation in the Odd1 gene and show that Odd1 is essential for heart and intermediate mesoderm development. Odd1.sup.-/- mutant mouse embryos fail to form atrial septum, display dilated atria with hypoplastic venous valves, and exhibit blood backflow from the heart into systemic veins. In contrast to other transcription factors implicated in atrial septum development, Odd1 mRNA expression is restricted to the central dorsal domain of the atrial myocardium during normal heart development. Moreover, expression patterns of known key regulatory genes of atrial septum development, including Nkx2.5, Pitx2, and Tbx5, are unaltered in the developing heart in Odd1.sup.-/- mutants compared to that of the wild-type littermates. Furthermore, homozygous Odd1.sup.-/- mutant embryos exhibit complete agenesis of adrenal glands, metanephric kidneys, gonads, and defects in pericardium formation. Detailed molecular marker analyses show that key regulators of early intermediate mesoderm development, including Lhx1, Pax2, and Wt1, are all down-regulated and nephrogenic mesenchyme undergoes massive apoptosis, resulting in disruption of nephric duct elongation and failure of metanephric induction in the Odd1.sup.-/- mutant embryos. These data provide new insights into the molecular mechanisms underlying heart morphogenesis and urogenital development. Author Affiliation: Center for Oral Biology and Department of Biomedical Genetics, University of Rochester School of Medicine and Dentistry, 601 Elmwood Avenue, Box 611, Rochester, NY 14642, USA Article History: Received 7 June 2005; Revised 7 September 2005; Accepted 13 September 2005

A mouse model is used to delineate the underlying molecular mechanisms for urogenital development and heart morphogensis.

Understanding the CO 2 capture performance of individual amines based on their structure is essential for efficient CO 2 capture. In this study, the effects of the molecular structure of amine on CO 2 loading, cyclic capacity, absorption–desorption rate, and p K a were investigated, and promising candidates for CO 2 capture, along with an amine blending strategy, were proposed. The results showed that electron-donating alkyl groups increased the CO 2 loading by increasing the electron density and p K a of the amino groups, whereas the electron-withdrawing hydroxyl group exhibited the opposite effect. Thirty amines were tested and categorized into Group A, B, C, and D based on CO 2 absorption rate and cyclic capacity. Amines in Group B had a slow absorption rate but high cyclic capacity and included sterically hindered primary or secondary amines (2-amino-2-methyl-1-propanol, 2-(isopropylamino)ethanol, and 2-(tert-butylamino)ethanol) and sterically hindered tertiary amines with one hydroxyl group on the β–carbon (1-dimethylamino-2-propanol, 1-(2-hydroxyethyl)piperidine, N,N -diethylethanolamine and 1-diethylamino-2-propanol). The best-performing amines, Group A, were primarily multiamines (1-(2-hydroxyethyl)piperazine, 2-methylpiperazine, 2-(2-aminoethylamino)ethanol, N,N -dimethyl-1,3-propanediamine, N , N -diethyl-1,3-diaminopropane, hexamethylenediamine, diethylenetriamine, and 3,3'-diamno- N -methyldipropylamine) and included a sterically hindered heterocyclic secondary amine (2-piperidineethanol) with a hydroxyalkyl substituent on the α–carbon. Thus, amines in Group A are promising absorbents for CO 2 capture, and blending amines in Group B with amines that have a high CO 2 absorption rate (e.g., Group A) can also be a potential strategy for efficient CO 2 capture. • CO 2 capture performances are governed by the molecular structure of amines. • Alkyl groups act as electron donors, increasing CO 2 loading, p K a , and cyclic capacity. • Hydroxyl groups negatively affect the CO 2 loading, p K a , and cyclic capacity. • The capture performance of tertiary amines showed a strong dependence on p K a. • Multiamines and heterocyclic secondary amines with α-carbon alkyl groups are potential amines. [ABSTRACT FROM AUTHOR]

Alopecia is defined as hair loss in a part of the head due to various causes, such as drugs, stress and autoimmune disorders. Various therapeutic agents have been suggested depending on the cause of the condition and patient sex, and age. Minoxidil (MXD) is commonly used topically to treat alopecia, but its low absorption rate limits widespread use. To overcome the low absorption, we suggest microneedles (MNs) as controlled drug delivery systems that release MXD. We used hyaluronic acid (HA) to construct MN, as it is biocompatible and safe. We examined the effect of HA on the hair dermal papilla (HDP) cells that control the development of hair follicles. HA enhanced proliferation, migration, and aggregation of HDP cell by increasing cell-cell adhesion and decreasing cell substratum. These effects were mediated by the cluster of differentiation (CD)-44 and phosphorylation of serine‑threonine kinase (Akt). In chemotherapy-induced alopecia mice, topical application of HA tended to decrease chemotherapy-induced hair loss. Although the amount of MXD administered by HA-MNs was 10% of topical treatment, the MXD-containing HA-MNs (MXD-HA-MNs) showed better effects on the growth of hair than topical application of MXD. In summary, our results demonstrated that HA reduces hair loss in alopecia mice, and that delivery of MXD and HA using MXD-HA-MNs maximizes therapeutic effects and minimize the side effects of MXD for the treatment of alopecia. (1) Significance, This work reports a new approach for treatment of alopecia using a dissolving microneedle (MN) prepared with hyaluronic acid (HA). The HA provided a better environment for cellular functions in the hair dermal papilla cells. The HA-MNs containing minoxidil (MXD) exhibited a significant reduction of hair loss, although amount of MXD contained in them was only 10% of topically applied MXD., (2) Scientific impact, This is the first report demonstrating the direct anti-alopecia effects of HA administrated in a transdermal route and the feasibility of novel therapeutics using MXD-containing HA-MNs. We believe that our work will excite interdisciplinary readers of Acta Biomaterialia, those who are interested in the natural polymers, drug delivery, and alopecia. [Display omitted] [ABSTRACT FROM AUTHOR]

Considering various shopping behavior helps in formulating day-of-the-week models that seek to enhance daily analysis of shopping activity patterns. Analysis of day-of-the-week models reveals the existence of the difference between parameter estimates and statistical data contained in every model. A nested logit model is also found to be feasible in representing shopping activity patterns of families.

Numerous studies highlight the potential benefits potentials of supplemental cartilage oligomeric matrix proteinangiopoietin-1 (COMP-Ang1) through improved angiogenic effects. However, our recent findings show that excessive overexpression of COMP-Ang1 induces an impaired bone marrow (BM) microenvironment and senescence of hematopoietic stem cells (HSCs). Here, we investigated the underlying mechanisms of how excessive COMP-Ang1 affects the function of BM-conserved stem cells and hematopoiesis using K14-Cre;inducible-COMP-Ang1-transgenic mice. Excessive COMP-Ang1 induced peripheral egression and senescence of BM HSCs and mesenchymal stem cells (MSCs). Excessive COMP-Ang1 also caused abnormal hematopoiesis along with skewed differentiation of HSCs toward myeloid lineage rather than lymphoid lineage. Especially, excessive COMP-Ang1 disturbed late-stage erythroblast maturation, followed by decreased expression of stromal cell-derived factor 1 (SDF-1) and globin transcription factor 1 (GATA-1) and increased levels of superoxide anion and p-p38 kinase. However, transplantation with the mutant-derived BM cells or treatment with rhCOMP-Ang1 protein did not alter the frequency or GATA-1 expression of erythroblasts in recipient mice or in cultured BM cells. Together, our findings suggest that excessive COMP-Ang1 impairs the functions of BM HSCs and MSCs and hematopoietic processes, eventually leading to abnormal erythropoiesis via imbalanced SDF-1/CXCR4 axis and GATA-1 expression rather than Ang1/Tie2 signaling axis alterations. [ABSTRACT FROM AUTHOR]