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1.
Forensic Sci Int ; 151(2-3): 193-200, 2005 Jul 16.
Article in English | MEDLINE | ID: mdl-15939152

ABSTRACT

Weathering or long-term burial may cause profound morphological and histological changes in hair, which may affect the results of forensic and archaeological investigations. We therefore used ultramicroscopic techniques to assay the changes in weathering hair shafts caused by burial for up to 25 years. We found that the middle portion of hair shafts from living individuals shows the expected histological hair structure, while the cuticle layer was absent from the terminal portion of the same hairs, which may be due to the increased weathering experienced by the terminal portion. In hair samples taken 5 years after death, no significant changes in morphology were observed. By 15 years after death, however, we observed losses in various layers of the hair, including the cuticle layer. At 25 years after death, hair shafts showed a number of pores extending into the medulla, with only some hair shafts retaining their cortical layers. To our knowledge, this is the first ultramicroscopic study on weathering of hair for up to 25 years after death. Our results may therefore provide a basis for similar studies in the fields of forensic science and physical anthropology.


Subject(s)
Environmental Exposure , Forensic Anthropology , Hair/ultrastructure , Postmortem Changes , Weather , Burial , Female , Humans , Male , Microscopy , Middle Aged , Time Factors
2.
FEBS Lett ; 575(1-3): 41-51, 2004 Sep 24.
Article in English | MEDLINE | ID: mdl-15388331

ABSTRACT

Male germ cell apoptosis has been extensively explored in rodents. In contrast, very little is known about the susceptibility of developing germ cells to apoptosis in response to busulfan treatment. Spontaneous apoptosis of germ cells is rarely observed in the adult mouse testis, but under the experimental conditions described here, busulfan-treated mice exhibited a marked increase in apoptosis and a decrease in testis weight. TdT-mediated dUTP-X nicked end labeling analysis indicates that at one week following busulfan treatment, apoptosis was confined mainly to spermatogonia, with lesser effects on spermatocytes. The percentage of apoptosis-positive tubules and the apoptotic cell index increased in a time-dependent manner. An immediate effect was observed in spermatogonia within one week of treatment, and in the following week, secondary effects were observed in spermatocytes. RT-PCR analysis showed that expression of the spermatogonia-specific markers c-kit and Stra 8 was reduced but that Gli I gene expression remained constant, which is indicative of primary apoptosis of differentiating type A spermatogonia. Three and four weeks after busulfan treatment, RAD51 and FasL expression decreased to nearly undetectable levels, indicating that meiotic spermatocytes and post-meiotic cells, respectively, were lost. The period of germ cell depletion did not coincide with increased p53 or Fas/FasL expression in the busulfan-treated testis, although p110Rb phosphorylation and PCNA expression were inhibited. These data suggest that increased depletion of male germ cells in the busulfan-treated mouse is mediated by loss of c-kit/SCF signaling but not by p53- or Fas/FasL-dependent mechanisms. Spermatogonial stem cells may be protected from cell death by modulating cell cycle signaling such that E2F-dependent protein expression, which is critical for G1 phase progression, is inhibited.


Subject(s)
Alkylating Agents/pharmacology , Apoptosis/physiology , Busulfan/pharmacology , Germ Cells , Membrane Glycoproteins/metabolism , Proto-Oncogene Proteins c-kit/metabolism , Tumor Suppressor Protein p53/metabolism , fas Receptor/metabolism , Adaptor Proteins, Signal Transducing , Animals , Biomarkers , DNA-Binding Proteins/metabolism , Fas Ligand Protein , Gene Expression Regulation, Developmental , Germ Cells/cytology , Germ Cells/drug effects , Germ Cells/physiology , Humans , In Situ Nick-End Labeling , Male , Membrane Glycoproteins/genetics , Mice , Organ Size , Proliferating Cell Nuclear Antigen/metabolism , Proteins/metabolism , Proto-Oncogene Proteins c-kit/genetics , Rad51 Recombinase , Retinoblastoma Protein/metabolism , Signal Transduction/physiology , Testis/cytology , Testis/drug effects , Testis/metabolism , Tumor Suppressor Protein p53/genetics , fas Receptor/genetics
3.
Arch Insect Biochem Physiol ; 52(2): 92-103, 2003 Feb.
Article in English | MEDLINE | ID: mdl-12529864

ABSTRACT

Three antibacterial peptides, named protaetins 1, 2, and 3, were purified and characterized from immunized larval hemolymph of Protaetia brevitarsis, a fruit tree pest in Korea. Also, protaetin 1 was cloned. Acid extraction, gel filtration, preparative acid-urea PAGE, and reversed-phase FPLC were used for purification of peptides. Protaetins 1 and 3 had molecular masses of 7.5 and 12 kDa on Tricine SDS-PAGE, respectively, and the molecular mass of protaetin 2 was 9,283.95 Da as determined by MALDI-TOF mass spectrometry. In an antibacterial assay, protaetins showed antibacterial activities against a panel of Gram-positive and -negative bacteria. For the RT-PCR (reverse transcription polymerase chain reaction) to obtain the complete primary sequence, the primer was designed according to the N-terminal amino acid sequence of protaetin 1. Amino acid sequence homology of protaetin 1 with holotricin 2, an antibacterial peptide from Holotrichia diomphalia, showed 99% identity. Northern blot analysis showed that the protaetin 1 gene was strongly expressed in the fat body after Escherichia coli injection, but not in normal fat body. Also, it was expressed in the gut, but was much weaker after immunization.


Subject(s)
Anti-Bacterial Agents/isolation & purification , Coleoptera/genetics , DNA, Complementary/genetics , Insect Proteins/genetics , Peptides , Amino Acid Sequence , Animals , Anti-Bacterial Agents/biosynthesis , Anti-Bacterial Agents/pharmacology , Base Sequence , Blotting, Northern , Cloning, Molecular , Coleoptera/chemistry , Electrophoresis, Polyacrylamide Gel/methods , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/drug effects , Hemolymph/chemistry , Insect Proteins/isolation & purification , Insect Proteins/pharmacology , Larva/chemistry , Microbial Sensitivity Tests , Molecular Sequence Data , Reverse Transcriptase Polymerase Chain Reaction , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods
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