Acne Scars

Mol Plant Pathol. 2009 May; 10(3): 403-14Aveskamp MM, Woudenberg JH, de Gruyter J, Turco E, Groenewald JZ, Crous PWPhoma exigua is considered to be an assemblage of at least nine varieties that are mainly distinguished on the basis of host specificity and pathogenicity. However, these varieties are also reported to be weak pathogens and secondary invaders on non-host tissue. In practice, it is difficult to distinguish P. exigua from its close relatives and to correctly identify isolates up to the variety level, because of their low genetic variation and high morphological similarity. Because of quarantine issues and phytosanitary measures, a robust DNA-based tool is required for accurate and rapid identification of the separate taxa in this species complex. The present study therefore aims to develop such a tool based on unique nucleotide sequence identifiers. More than 60 strains of P. exigua and related species were compared in terms of partial actin gene sequences, or analysed using DNA amplification fingerprinting (DAF) with short, arbitrary, mini-hairpin primers. Fragments in the fingerprint unique to a single taxon were identified, purified and sequenced. Alignment of the sequence data and subsequent primer trials led to the identification of taxon-specific sequence characterized amplified regions (SCARs), and to a set of specific oligonucleotide combinations that can be used to identify these organisms in plant quarantine inspections.

Ann N Y Acad Sci. 2009 Apr; 1160: 336-41Stewart DRRelaxin has previously been tested in rodent wound healing models and been shown to promote angiogenesis and to speed healing. However, pigs have been shown to be a better model for human skin in dermatology studies, so juvenile pigs were selected for a study of scar reduction and cosmetic appearance. Twelve 20- by 6-mm excisional wounds were created on the backs of all animals. Topical formulations of relaxin with 0, 0.5, or 2.5 mg/mL were applied twice daily for weeks 2-3 and then daily for weeks 3-6 in all animals. In addition, some animals received systemic relaxin, which was administered via infusion pumps at a rate of 125 microg/kg of body weight/day. Assessments of healing and cosmetic appearance were made by a dermatologist at weeks 2, 4, and 6. Wound sites were collected at 6 weeks and evaluated histologically for granulation tissue, inflammation, and collagen organization. Wounds in animals receiving systemic relaxin had an improved appearance with less redness, reduced granulation tissue, and lower amounts of inflammation. They showed a more-well-knit collagen structure compared to controls. Wounds treated with topical formulations did not show improvement over controls. The topical formulation used was found to have a short residence time, which likely limited penetration of relaxin. Reformulated relaxin preparations with improved penetration might be useful as a topical treatment for wounds to prevent or reduce scarring.

J Tissue Eng Regen Med. 2009 May 5; Ramos TV, Wang T, Maki CB, Pascual M, Izadyar FAdipose tissue has become a reliable source of adult stem cells, which appear to possess a yet-undetermined degree of plasticity. With the difficulties associated with harvesting adult bone marrow stem cells, adipose tissue may represent a valuable and easily acquired source of stem cells. Stem cells have been identified using the DNA binding dye Hoechst 33342 and flow cytometry in various tissues known as the side population (SP). The present study shows, for the first time, the presence of side population stem cells in adult adipose tissues. Flow cytometric identification and isolation of this subpopulation of stem cells revealed that in the mouse there are 2.5% of adipose SP cells within the stromal vascular fraction of adipose tissue. In culture, mouse adipose SP cells showed the capacity to undergo in vitro differentiation into osteogenic, chondrogenic and adipogenic lineages. In NOD/SCID mice, freshly sorted mouse adipose SP cells were able to engraft and assist in wound healing. This animal model study showed that adipose SP cells were able to regenerate epithelial layers and connective tissue with minor scar formation. The ability of this novel cell population within adipose tissue to undergo directional differentiation in vitro and to regenerate skin in vivo has potential impact for uses in surgical dermal applications. Copyright (c) 2009 John Wiley & Sons, Ltd.

J Comp Neurol. 2009 Mar 20; 515(2): 197-214Rehermann MI, Marichal N, Russo RE, Trujillo-Cenóz OThis paper provides the first evidence that freshwater turtles are able to reconnect their completely transected spinal cords, leading to some degree of recovery of the motor functions lost after injury. Videographic analysis showed that some turtles (5 of 11) surviving more than 20 days after injury were able to initiate stepping locomotion. However, the stepping movements were slower than those of normal animals, and swimming patterns were not restored. Even though just 45% of the injured turtles recovered their stepping patterns, all showed axonal sprouting beyond the lesion site. Immunocytochemical and electron microscope images revealed the occurrence of regrowing axons crossing the severed region. A major contingent of the axons reconnecting the cord originated from sensory neurons lying in dorsal ganglia adjacent to the lesion site. The axons bridging the damaged region traveled on a cellular scaffold consisting of brain lipid-binding protein (BLBP)- and glial fibrillary acidic protein (GFAP)-positive cells and processes. Serotonergic varicose nerve fibers and endings were found at early stages of the healing process at the epicenter of the lesion. Interestingly, the glial scar commonly found in the damaged central nervous system of mammals was absent. In contrast, GFAP- and BLBP-positive processes were found running parallel to the main axis of the cord accompanying the crossing axons. J. Comp. Neurol. 515:197-214, 2009. (c) 2009 Wiley-Liss, Inc.