In this review we intend to provide a relatively comprehensive summary of the work of supramolecular hydrogelators after 2004 and to put emphasis particularly on the applications of supramolecular hydrogels/hydrogelators as molecular biomaterials. After a brief introduction of methods for generating supramolecular hydrogels, we discuss supramolecular hydrogelators on the basis of their categories, such as small organic molecules, coordination complexes, peptides, nucleobases, and saccharides. Following molecular design, we focus on various potential applications of supramolecular hydrogels as molecular biomaterials, classified by their applications in cell cultures, tissue engineering, cell behavior, imaging, and unique applications of hydrogelators. Particularly, we discuss the applications of supramolecular hydrogelators after they form supramolecular assemblies but prior to reaching the critical gelation concentration because this subject is less explored but may hold equally great promise for helping ...

Supramolecular Hydrogelators and Hydrogels: From Soft Matter to Molecular Biomaterials

Alkaline phosphatase (ALP; E.C.3.I.3.1.) is an ubiquitous membrane-bound glycoprotein that catalyzes the hydrolysis of phosphate monoesters at basic pH values. Alkaline phosphatase is divided into four isozymes depending upon the site of tissue expression that are Intestinal ALP, Placental ALP, Germ cell ALP and tissue nonspecific alkaline phosphatase or liver/bone/kidney (L/B/K) ALP. The intestinal and placental ALP loci are located near the end of long arm of chromosome 2 and L/B/K ALP is located near the end of the short arm of chromosome 1. Although ALPs are present in many mammalian tissues and have been studied for the last several years still little is known about them. The bone isoenzyme may be involved in mammalian bone calcification and the intestinal isoenzyme is thought to play a role in the transport of phosphate into epithelial cells of the intestine. In this review, we tried to provide an overview about the various forms, structure and functions of alkaline phosphatase with special focus on liver/bone/kidney alkaline phosphatase.

/pdf/alkaline-phosphatase-an-overview-2n1756ossx.pdf

Alkaline Phosphatase: An Overview

The human alkaline phosphatases: What we know and what we don't know

Perspectives on alkaline phosphatase isoenzymes

We report the inactivation, via homologous recombination, of two of the three active mouse alkaline phosphatase genes, i.e., embryonic (EAP) and tissue nonspecific (TNAP). Whereas expression of the EAP isozyme was abolished in all tissues that express EAP developmentally (such as the preimplantation embryo, thymus, and testis), the EAP knock-out mice show no obvious phenotypic abnormalities. They reproduce normally and give birth to live offspring, indicating the nonessential role of EAP during embryonic development. Mice deficient in the TNAP gene mimic a severe form of hypophosphatasia. These TNAP-/- mice are growth impaired, develop epileptic seizures and apnea, and die before weaning. Examination of the tissues indicates abnormal bone mineralization and morphological changes in the osteoblasts, aberrant development of the lumbar nerve roots, disturbances in intestinal physiology, increased apoptosis in the thymus, and abnormal spleens. Our results indicate that, in the mouse, TNAP appears not to be essential for the initial events leading to bone mineral deposition but that TNAP seems to play a role in the maintenance of this process after birth. The other phenotypic manifestations may be a consequence of the lack of TNAP in the developing neural tube between stages E8.5 and E13.5 of embryogenesis. We hypothesize that the autonomic nervous system is compromised in these TNAP-/- mice.

https://anatomypubs.onlinelibrary.wiley.com/doi/pdf/10.1002/%28SICI%291097-0177%28199703%29208%3A3%3C432%3A%3AAID-AJA13%3E3.0.CO%3B2-1

Inactivation of two mouse alkaline phosphatase genes and establishment of a model of infantile hypophosphatasia

Derepression of the genome of the cancer cell may explain why certain cancer patients exhibit an isoenzyme of alkaline phosphatase biochemically and immunologically indistinguishable from human placental alkaline phosphatase.

Immunology and biochemistry of Regan isoenzyme of alkaline phosphatase in human cancer.

Summary We observed an unexpectedly high incidence of the D-variant placental phenotype in Regan isoenzyme-positive sera of cancer patients: Such D-variant-positive sera exhibit a high degree of inhibition by l-leucine, a phenomenon earlier associated with the Nagao isoenzyme. Unlike normal placentae, a diffuse phenotype of heat-stable alkaline phosphatase is usually noted in cancer sera containing Nagao isoenzyme.

/pdf/phenotypes-of-the-regan-isoenzyme-and-identity-between-the-3jv5dl4vep.pdf

Phenotypes of the Regan Isoenzyme and Identity between the Placental D-Variant and the Nagao Isoenzyme

Distinctions between intestinal and placental isoenzymes of alkaline phosphatase

The serum alkaline phosphatase isoenzymes of 56 normal individuals have been studied from three points of view: the partition of intestinal type alkaline phosphatase from nonintestinal by L-phenylalanine inhibition and their respective heat sensitivities; the performance of starch gel electrophoresis; and acrylamide gel electrophoresis of all sera. The improved acrylamide gel electrophoresis technic did separate bone and liver isoenzymes more effectively than starch gel electrophoresis. The liver position of every subject was seen as the fastest moving compact band and had relatively low heat inactivation, whereas the bone band was slower, less compact, and had a high heat inactivation. The intestinal position was easily observed on starch gel electrophoresis, and was visualized on acrylamide gel by the subsequent use of the liver and bone inhibitor, L-homoarginine, in the substrate medium. These results show the heterogeneity of alkaline phosphatase isoenzymes in the serum of the normal individual.

Normal Serum Alkaline Phosphatase Isoenzymes Examined by Acrylamide and Starch Gel Electrophoresis and by Isoenzyme Analysis Using Organ-specific Inhibitors

Summary The Regan isoenzyme3 of alkaline phosphatase of human cancer tissue first described in this journal (9) is a carcinoplacental antigen. The experimental evidence shows lines of identity between alkaline phosphatase antigens of placental and tumor tissue origin and corresponding rabbit antisera to these antigens. Also, the loss in the enzyme activity of the antigen in both antigen-antibody complexes is identical within the limits of experimental error as a function of dilution of antiserum. The reasons for considering Regan isoenzyme antigen carcinoplacental as opposed to fetal are presented.

/pdf/regan-isoenzyme-a-carcinoplacental-antigen-5af2flna30.pdf

Norma R. Inglis

Papers

Immunology and biochemistry of Regan isoenzyme of alkaline phosphatase in human cancer.

Phenotypes of the Regan Isoenzyme and Identity between the Placental D-Variant and the Nagao Isoenzyme

Distinctions between intestinal and placental isoenzymes of alkaline phosphatase

Normal Serum Alkaline Phosphatase Isoenzymes Examined by Acrylamide and Starch Gel Electrophoresis and by Isoenzyme Analysis Using Organ-specific Inhibitors

Regan Isoenzyme: A Carcinoplacental Antigen