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1.
Sci Rep ; 8(1): 16720, 2018 11 13.
Article in English | MEDLINE | ID: mdl-30425256

ABSTRACT

Plant root systems play many key roles including nutrient and water uptake, interface with soil microorganisms and resistance to lodging. As for other crops, large and systematic studies of sugarcane root systems have always been hampered by the opaque and solid nature of the soil. In recent years, methods for efficient extraction of DNA from soil and for species-specific DNA amplification have been developed. Such tools could have potential to greatly improve root phenotyping and health diagnostic capability in sugarcane. In this paper, we present a fast, specific and efficient method for the quantification of sugarcane live root cells in soil samples. Previous studies were typically based on mass and length, so we established a calibration to convert root DNA quantity to live root mass. This diagnostic was validated on field samples and used to investigate the fate of the root system after harvest prior to regrowth of the ratoon crop. Two weeks after harvest, the sugarcane roots from the previous crop were still viable. This raises the question of the role that the root system of the harvested crop plays in the performance of the next crop and demonstrates how this test can be used to answer research questions.


Subject(s)
DNA, Plant/analysis , Plant Roots/genetics , Saccharum/genetics , DNA Copy Number Variations/genetics , DNA, Plant/genetics , Dipeptides/pharmacology , Fertilizers , Nitrogen/pharmacology , Plant Roots/drug effects , Polymerase Chain Reaction , Saccharum/drug effects , Saccharum/physiology , Soil/chemistry , Taq Polymerase/metabolism , Tissue Survival/drug effects , Tissue Survival/genetics
2.
PLoS One ; 13(10): e0204942, 2018.
Article in English | MEDLINE | ID: mdl-30286140

ABSTRACT

The evolutionary conserved miR-125b is highly expressed in hematopoietic stem cells (HSC) enhancing self-renewal and survival. Accordingly, over-expression of miR-125b in HSC may induce myeloproliferative neoplasms and leukemia with long latency. During hematopoietic cell maturation miR-125b expression decreases, and the function of miR-125b in mature granulocytes is not yet known. We here use transplantation of miR-125b over-expressing HSC into syngeneic hosts to generate and analyse miR-125b over-expressing granulocytes. Under steady state conditions, miR-125b over-expression inhibits granulocytic chemotaxis and LPS- but not PMA- and TNFα- induced cell death. Inflammatory signals modulate the effects of miR-125b over-expression as demonstrated in a sterile peritonitis and a polymicrobial sepsis model. In particular, survival of mice with miR-125b over-expressing granulocytes is significantly reduced as compared to controls in the polymicrobial sepsis model. These data demonstrate inflammation dependent effects of miR-125b in granulocytes and may point to therapeutic intervention strategies in the future.


Subject(s)
Bone Marrow Cells/cytology , Chemotaxis/genetics , Granulocytes/cytology , MicroRNAs/genetics , Tissue Survival/genetics , Animals , Cell Differentiation/genetics , Female , Gene Expression Regulation , HEK293 Cells , Humans , Mice , Mice, Inbred C57BL , Sepsis/genetics
3.
J Lipid Res ; 57(3): 410-21, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26685326

ABSTRACT

Cholesterol and fatty acid biosynthesis are regulated by the sterol regulatory element-binding proteins (SREBPs), encoded by Srebf1 and Srebf2. We generated mice that were either deficient or hypomorphic for SREBP-2. SREBP-2 deficiency generally caused death during embryonic development. Analyses of Srebf2(-/-) embryos revealed a requirement for SREBP-2 in limb development and expression of morphogenic genes. We encountered only one viable Srebf2(-/-) mouse, which displayed alopecia, attenuated growth, and reduced adipose tissue stores. Hypomorphic SREBP-2 mice (expressing low levels of SREBP-2) survived development, but the female mice exhibited reduced body weight and died between 8 and 12 weeks of age. Male hypomorphic mice were viable but had reduced cholesterol stores in the liver and lower expression of SREBP target genes. Reduced SREBP-2 expression affected SREBP-1 isoforms in a tissue-specific manner. In the liver, reduced SREBP-2 expression nearly abolished Srebf1c transcripts and reduced Srebf1a mRNA levels. In contrast, adipose tissue displayed normal expression of SREBP target genes, likely due to a compensatory increase in Srebf1a expression. Our results establish that SREBP-2 is critical for survival and limb patterning during development. Reduced expression of SREBP-2 from the hypomorphic allele leads to early death in females and reduced cholesterol content in the liver, but not in adipose tissue.


Subject(s)
Embryonic Development/genetics , Gene Expression Regulation, Developmental , Sterol Regulatory Element Binding Protein 1/genetics , Sterol Regulatory Element Binding Protein 2/deficiency , Sterol Regulatory Element Binding Protein 2/genetics , Adipose Tissue/metabolism , Adiposity/genetics , Alleles , Animals , Cell Line , Extremities/embryology , Female , Homeostasis/genetics , Lipid Metabolism/genetics , Liver/metabolism , Male , Mice , Mutation , Sex Characteristics , Sterol Regulatory Element Binding Protein 1/metabolism , Sterol Regulatory Element Binding Protein 2/metabolism , Tissue Survival/genetics
4.
Ren Fail ; 37(1): 108-12, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25365635

ABSTRACT

BACKGROUND: The mitochondrial displacement loop (D-loop) is known to accumulate mutations and SNPs at a higher frequency than other regions of mitochondrial DNA (mtDNA). We had identified chronic kidney disease (CKD) risk-associated SNPs in the D-loop of CKD patients previously. In this study, we investigated the association of SNPs in the D-loop of mtDNA with the kidney survival of CKD. METHODS: The D-loop region of mtDNA was sequenced for 119 CKD patients from the inpatient of the Fourth Hospital of Hebei Medical University. The Kaplan-Meier method was used to identify disease outcome-associated SNPs in the D-loop of CKD patients. The Cox proportional hazards model was used to identify risk factors for the kidney survival of CKD. RESULTS: In the present study, we identified 20 SNPs with a frequency higher than 5% and assessed the relationship of these SNPs with kidney survival time in CKD patients, a SNP of 146 was identified by log-rank test for statistically significant prediction of the kidney survival time. In an overall multivariate analysis, allele 146 was identified as an independent predictor of kidney survival time in CKD patients. The survival time of kidney in the CKD patients with 146C was significantly shorter than that of kidney in CKD patients with 146T (relative risk, 2.336; 95% CI, 1.319-3.923; p = 0.001). CONCLUSION: SNPs in the D-loop can predict the kidney survival of CKD patients. Analysis of genetic polymorphisms in the mitochondrial D-loop can help to identify CKD patient subgroup at high risk of a poor disease outcome.


Subject(s)
DNA, Mitochondrial , Kidney , Renal Insufficiency, Chronic , Adult , Aged , Disease Progression , Female , Genes, Mitochondrial , Genome-Wide Association Study , Glomerular Filtration Rate , Humans , Kidney/pathology , Kidney/physiopathology , Male , Middle Aged , Mutation , Polymorphism, Single Nucleotide , Prognosis , Proportional Hazards Models , Prospective Studies , Renal Insufficiency, Chronic/genetics , Renal Insufficiency, Chronic/pathology , Renal Insufficiency, Chronic/physiopathology , Risk Factors , Tissue Survival/genetics
5.
BMC Plant Biol ; 14: 176, 2014 Jun 27.
Article in English | MEDLINE | ID: mdl-24972689

ABSTRACT

BACKGROUND: Pollen of common ragweed (Ambrosia artemisiifolia) is a main cause of allergic diseases in Northern America. The weed has recently become spreading as a neophyte in Europe, while climate change may also affect the growth of the plant and additionally may also influence pollen allergenicity. To gain better insight in the molecular mechanisms in the development of ragweed pollen and its allergenic proteins under global change scenarios, we generated SuperSAGE libraries to identify differentially expressed transcripts. RESULTS: Ragweed plants were grown in a greenhouse under 380 ppm CO2 and under elevated level of CO2 (700 ppm). In addition, drought experiments under both CO2 concentrations were performed. The pollen viability was not altered under elevated CO2, whereas drought stress decreased its viability. Increased levels of individual flavonoid metabolites were found under elevated CO2 and/or drought. Total RNA was isolated from ragweed pollen, exposed to the four mentioned scenarios and four SuperSAGE libraries were constructed. The library dataset included 236,942 unique sequences, showing overlapping as well as clear differently expressed sequence tags (ESTs). The analysis targeted ESTs known in Ambrosia, as well as in pollen of other plants. Among the identified ESTs, those encoding allergenic ragweed proteins (Amb a) increased under elevated CO2 and drought stress. In addition, ESTs encoding allergenic proteins in other plants were also identified. CONCLUSIONS: The analysis of changes in the transcriptome of ragweed pollen upon CO2 and drought stress using SuperSAGE indicates that under global change scenarios the pollen transcriptome was altered, and impacts the allergenic potential of ragweed pollen.


Subject(s)
Allergens/immunology , Ambrosia/genetics , Ambrosia/physiology , Carbon Dioxide/pharmacology , Droughts , Gene Expression Profiling , Pollen/immunology , Stress, Physiological/genetics , Ambrosia/drug effects , Chromatography, High Pressure Liquid , Chromatography, Reverse-Phase , Databases, Genetic , Down-Regulation/drug effects , Down-Regulation/genetics , Expressed Sequence Tags , Gene Expression Regulation, Plant/drug effects , Gene Library , RNA, Messenger/genetics , RNA, Messenger/metabolism , Real-Time Polymerase Chain Reaction , Secondary Metabolism/drug effects , Stress, Physiological/drug effects , Tissue Survival/drug effects , Tissue Survival/genetics , Up-Regulation/drug effects , Up-Regulation/genetics
6.
Laryngorhinootologie ; 92(7): 462-9, 2013 Jul.
Article in German | MEDLINE | ID: mdl-23592442

ABSTRACT

BACKGROUND: Mesenchymal stem cells (MSCs) are adult fibroblastoid progenitor cells. Because of their immunoregulatory properties and their so-called trophic effects, MSCs play an important role in tissue regeneration, inflammation and trauma. Tissue trauma and challenge, for example during radiotherapy or infection, result in the release of so-called "danger molecules", which may be derived from dying cells or incoming pathogens. The molecular response of MSCs to this tissue stress remains largely elusive. MATERIAL AND METHODS: In this study we examined the cell biological response of MSCs derived from human parotid glands (pgMSCs) and used bacterial endotoxin as a model of tissue stress and inflammation. PgMSCs from 3 donors were isolated, expanded and tested for classical tri-lineage plus myogenic differentiation. The cell biological response to the model "stressor" endotoxin was examined by low density gene expression arrays. RESULTS: Through immunofluorescence and immunohistochemistry we were able to proof osteogenic, adipogenic, chondrogenic, and myogenic differentiation potential characteristic for stem cells. In vitro, gene expression analysis showed a characteristic modulation of MSCs after stimulation with endotoxin Lipopolysaccharide (LPS). Specifically, receptors and ligands typically involved in immune regulation, such as interleukins, TGF-ß, tumor necrosis factors (TNF), and toll-like receptors (TLR), were regulated. CONCLUSION: Our study elucidates some key functions and molecules, which are regulated in MSCs during tissue stress and inflammation. A thorough understanding of their cell biological function will aid future rationale therapeutic application of MSCs.


Subject(s)
Gene Expression Profiling/methods , Immunogenetic Phenomena/genetics , Immunogenetic Phenomena/immunology , Inflammation Mediators/physiology , Inflammation/genetics , Inflammation/immunology , Lipopolysaccharides/immunology , Mesenchymal Stem Cells/metabolism , Parotid Gland/cytology , Regenerative Medicine/methods , Tissue Survival/genetics , Tissue Survival/immunology , Adult , Cell Differentiation/genetics , Cell Differentiation/physiology , Female , Humans , In Vitro Techniques , Interferons/genetics , Interferons/physiology , Interleukins/genetics , Interleukins/physiology , Male , Middle Aged , Oligonucleotide Array Sequence Analysis , Toll-Like Receptors/genetics , Toll-Like Receptors/physiology , Transforming Growth Factor beta/genetics , Transforming Growth Factor beta/physiology , Tumor Necrosis Factor-alpha/genetics , Tumor Necrosis Factor-alpha/physiology
7.
PLoS Genet ; 9(2): e1003228, 2013.
Article in English | MEDLINE | ID: mdl-23459311

ABSTRACT

The alveolar compartment, the fundamental gas exchange unit in the lung, is critical for tissue oxygenation and viability. We explored hepatocyte growth factor (HGF), a pleiotrophic cytokine that promotes epithelial proliferation, morphogenesis, migration, and resistance to apoptosis, as a candidate mediator of alveolar formation and regeneration. Mice deficient in the expression of the HGF receptor Met in lung epithelial cells demonstrated impaired airspace formation marked by a reduction in alveolar epithelial cell abundance and survival, truncation of the pulmonary vascular bed, and enhanced oxidative stress. Administration of recombinant HGF to tight-skin mice, an established genetic emphysema model, attenuated airspace enlargement and reduced oxidative stress. Repair in the TSK/+ mouse was punctuated by enhanced akt and stat3 activation. HGF treatment of an alveolar epithelial cell line not only induced proliferation and scattering of the cells but also conferred protection against staurosporine-induced apoptosis, properties critical for alveolar septation. HGF promoted cell survival was attenuated by akt inhibition. Primary alveolar epithelial cells treated with HGF showed improved survival and enhanced antioxidant production. In conclusion, using both loss-of-function and gain-of-function maneuvers, we show that HGF signaling is necessary for alveolar homeostasis in the developing lung and that augmentation of HGF signaling can improve airspace morphology in murine emphysema. Our studies converge on prosurvival signaling and antioxidant protection as critical pathways in HGF-mediated airspace maintenance or repair. These findings support the exploration of HGF signaling enhancement for diseases of the airspace.


Subject(s)
Hepatocyte Growth Factor , Homeostasis , Proto-Oncogene Proteins c-met , Pulmonary Alveoli , Animals , Cell Movement/genetics , Cell Proliferation , Epithelial Cells/cytology , Epithelial Cells/metabolism , Hepatocyte Growth Factor/administration & dosage , Hepatocyte Growth Factor/genetics , Hepatocyte Growth Factor/metabolism , Mice , Morphogenesis/genetics , Morphogenesis/physiology , Proto-Oncogene Proteins c-met/deficiency , Proto-Oncogene Proteins c-met/genetics , Proto-Oncogene Proteins c-met/metabolism , Pulmonary Alveoli/metabolism , Pulmonary Alveoli/physiology , Pulmonary Emphysema/genetics , Pulmonary Emphysema/metabolism , Pulmonary Emphysema/physiopathology , Signal Transduction , Tissue Survival/genetics
8.
J Neurotrauma ; 30(6): 427-33, 2013 Mar 15.
Article in English | MEDLINE | ID: mdl-23102374

ABSTRACT

To evaluate the hypothesis that calpain 1 knockdown would reduce pathological damage and functional deficits after spinal cord injury (SCI), we developed lentiviral vectors encoding calpain 1 shRNA and eGFP as a reporter (LV-CAPN1 shRNA). The ability of LV-CAPN1 shRNA to knockdown calpain 1 was confirmed in rat NRK cells using Northern and Western blot analysis. To investigate the effects on spinal cord injury, LV-CAPN1shRNA or LV-mismatch control shRNA (LV-control shRNA) were administered by convection enhanced diffusion at spinal cord level T10 in Long-Evans female rats (200-250 g) 1 week before contusion SCI, 180 kdyn force, or sham surgery at the same thoracic level. Intraspinal administration of the lentiviral particles resulted in transgene expression, visualized by eGFP, in spinal tissue at 2 weeks after infection. Calpain 1 protein levels were reduced by 54% at T10 2 weeks after shRNA-mediated knockdown (p<0.05, compared with the LV-control group, n=3 per group) while calpain 2 levels were unchanged. Intraspinal administration of LV-CAPN1shRNA 1 week before contusion SCI resulted in a significant improvement in locomotor function over 6 weeks postinjury, compared with LV-control administration (p<0.05, n=10 per group). Histological analysis of spinal cord sections indicated that pre-injury intraspinal administration of LV-CAPN1shRNA significantly reduced spinal lesion volume and improved total tissue sparing, white matter sparing, and gray matter sparing (p<0.05, n=10 per group). Together, results support the hypothesis that calpain 1 activation contributes to the tissue damage and impaired locomotor function after SCI, and that calpain1 represents a potential therapeutic target.


Subject(s)
Calpain/deficiency , Calpain/genetics , Spinal Cord Injuries/genetics , Spinal Cord Injuries/metabolism , Animals , Calpain/physiology , Cell Line , Female , Gene Knockdown Techniques/methods , Motor Activity/genetics , RNA, Small Interfering/genetics , Rats , Rats, Long-Evans , Spinal Cord Injuries/physiopathology , Tissue Survival/genetics , Treatment Outcome
9.
Genet Mol Res ; 11(4): 4100-9, 2012 Nov 28.
Article in English | MEDLINE | ID: mdl-23079971

ABSTRACT

The genus Mesosetum is a primarily South American genus with 42 species. Mesosetum chaseae, regionally known as 'grama-do-cerrado', is abundant in the Pantanal Matogrossense (Brazil); it is a valuable resource for livestock and for environmental conservation. We collected specimens from the Nhecolandia sub-region of the Brazilian Pantanal, located in Corumbá, Mato Grosso do Sul, Brazil. We examined chromosome number, ploidy level, meiotic behavior, microgametogenesis, and pollen viability of 10 accessions. All the accessions were diploid, derived from x = 8, presenting 2n = 2x = 16 chromosomes. Chromosomes paired as bivalents showing, predominantly, two terminal chiasmata. Interstitial chiasmata were rare. Meiosis was quite normal producing only a few abnormal tetrads in some accessions. Microgametogenesis, after two mitotic divisions, produced three-celled pollen grains. Pollen viability was variable among plant and accessions and was not correlated with meiotic abnormalities.


Subject(s)
Chromosomes, Plant/genetics , Gametogenesis, Plant/genetics , Poaceae/genetics , Pollen/genetics , Tissue Survival/genetics , Brazil , Ecotype , Meiotic Prophase I/genetics , Poaceae/cytology , Pollen/cytology
10.
J Dent Res ; 91(2): 197-202, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22095070

ABSTRACT

Branching morphogenesis is essential for the formation of salivary glands, kidneys, lungs, and many other organs during development, but the mechanisms underlying this process are not adequately understood. Microarray and other gene expression methods have been powerful approaches for identifying candidate genes that potentially regulate branching morphogenesis. However, functional validation of the proposed roles for these genes has been severely hampered by the absence of efficient techniques to genetically manipulate cells within embryonic organs. Using ex vivo cultured embryonic mouse submandibular glands (SMGs) as models to study branching morphogenesis, we have identified new vectors for viral gene transfer with high efficiency and cell-type specificity to developing SMGs. We screened adenovirus, lentivirus, and 11 types of adeno-associated viruses (AAV) for their ability to transduce embryonic day 12 or 13 SMGs. We identified two AAV types, AAV2 and bovine AAV (BAAV), that are selective in targeting expression differentially to SMG epithelial and mesenchymal cell populations, respectively. Transduction of SMG epithelia with self-complementary (sc) AAV2 expressing fibroblast growth factor 7 (Fgf7) supported gland survival and enhanced SMG branching morphogenesis. Our findings represent, to our knowledge, the first successful selective gene targeting to epithelial vs. mesenchymal cells in an organ undergoing branching morphogenesis.


Subject(s)
Genes, Viral/genetics , Salivary Glands/embryology , Adenoviridae/genetics , Animals , Cattle , Cell Culture Techniques , Cell Line , Dependovirus/genetics , Epithelial Cells/physiology , Feasibility Studies , Fibroblast Growth Factor 7/genetics , Gene Expression Regulation, Developmental/genetics , Gene Transfer Techniques , Genes, Reporter/genetics , Genetic Vectors/genetics , Green Fluorescent Proteins/genetics , HEK293 Cells , Humans , Lentivirus/genetics , Luminescent Agents , Mesoderm/cytology , Mice , Morphogenesis/genetics , Organ Culture Techniques , Plasmids/genetics , Tissue Survival/genetics , Transduction, Genetic/methods , Transfection
11.
Expert Opin Biol Ther ; 8(1): 1-4, 2008 Jan.
Article in English | MEDLINE | ID: mdl-18081532

ABSTRACT

Xenotransplantation using pigs offers the prospect of an unlimited number of organs and cells for clinical transplantation. A major step forward has been achieved with the introduction of pigs homozygous for alpha1,3-galactosyltransferase gene-knockouts that do not express the major antigenic target for primate antipig antibodies (i.e., Galalpha1,3Gal). Heterotopic heart transplants have survived for 2-6 months in baboons. However, other immune and pathophysiologic barriers remain, including: i) anti-non-Gal antibodies and cells of the innate immune system; and ii) thrombogenesis associated with incompatibilities in the coagulation-anticoagulation systems of pig and primate. Further genetic modification of the organ-source pig to overcome these barriers is being undertaken.


Subject(s)
Cell Transplantation , Organ Transplantation , Transplantation, Heterologous/immunology , Transplantation, Heterologous/trends , Animals , Humans , Swine , Tissue Survival/drug effects , Tissue Survival/genetics , Tissue Survival/immunology , Transplantation Immunology/drug effects , Transplantation Immunology/genetics , Transplantation Immunology/immunology
12.
Liver Int ; 26(4): 451-6, 2006 May.
Article in English | MEDLINE | ID: mdl-16629649

ABSTRACT

BACKGROUND: Cold ischemia/reperfusion injury of the hepatic graft, an unsolved problem in liver transplantations, is attributed to the release of inflammatory cytokines, especially the tumor necrosis factor- (TNF) alpha, from activated Kupffer cells (KC). Therefore, the specific inhibition of TNF-alpha could improve the viability of the hepatic graft upon reperfusion. METHODS: We assessed the efficacy of TNF-alpha antisense (TNF-AS) oligodeoxynucleotides (ODNs) delivery to KC in a rodent liver transplantation model. RESULTS: Seventy-one percent of the animals that received 6 hours preserved grafts in baths of lactated Ringer's solution (4 degrees C) and were treated with TNF-AS survived for over 14 days. Eighty percent of the animals treated with vehicle, sense ODNs, or balanced salt saline (BSS) died. Four hours after reperfusion of the liver, a significant reduction was noted in livers treated with TNF-AS in the release of cytosolic enzymes from the hepatocytes and the serum TNF-alpha (P<0.05). The expressions of TNF-alpha on KC and of intercellular adhesion molecule-1 on sinusoidal endothelial cells were completely suppressed in TNF-AS-treated livers. CONCLUSIONS: TNF-AS delivery improves the viability of the hepatic graft, and this technique may solve hepatic graft nonfunction in a clinical setting.


Subject(s)
Liver Transplantation/physiology , Oligodeoxyribonucleotides, Antisense/genetics , Reperfusion Injury/prevention & control , Tumor Necrosis Factor-alpha/metabolism , Animals , Gene Transfer Techniques , Intercellular Adhesion Molecule-1/genetics , Intercellular Adhesion Molecule-1/metabolism , Kupffer Cells/metabolism , Kupffer Cells/pathology , Liver Transplantation/mortality , Liver Transplantation/pathology , Male , Rats , Rats, Inbred BN , Reperfusion Injury/metabolism , Sendai virus/genetics , Survival Rate , Tissue Survival/genetics , Tissue Survival/physiology , Transfection/methods , Tumor Necrosis Factor-alpha/genetics
13.
Int Endod J ; 38(11): 817-21, 2005 Nov.
Article in English | MEDLINE | ID: mdl-16218974

ABSTRACT

AIM: To investigate the expression of osteocalcin mRNA in young and in aged human dental pulp tissue to determine the characteristics of osteocalcin expression. METHODOLOGY: Human dental pulp tissues of the third molars were obtained from healthy young (17-23 years) and aged (>50 years) subjects, and total RNA was extracted. Osteocalcin mRNA expression was determined by RT-PCR and by quantitative real-time RT-PCR (QRT-PCR). The threshold cycle (Ct) value, which reflects the amount of PCR, was calculated and the difference between the value in young and aged pulp was statistically analysed. RESULTS: Osteocalcin mRNA was detected in all samples of human dental pulp tissue homogenates by RT-PCR analysis. Osteocalcin mRNA was expressed in young adult dental pulp but was decreased in aged human dental pulp. QRT-PCR analysis also showed a reduced expression of osteocalcin mRNA in aged human pulp. Expression of osteocalcin in young human pulp was significantly higher (about sixfold) than in aged pulp (P<0.01, Mann-Whitney U-test). CONCLUSION: Reduction of osteocalcin expression may be associated with the loss of viability in human dental pulp tissue, and may be a characteristic of aged human dental pulps.


Subject(s)
Aging/metabolism , Dental Pulp/metabolism , Osteocalcin/analysis , Adolescent , Adult , Aged , Aging/genetics , Female , Gene Expression Regulation , Humans , Male , Middle Aged , Osteocalcin/genetics , RNA, Messenger/analysis , Reverse Transcriptase Polymerase Chain Reaction , Tissue Survival/genetics
14.
Handchir Mikrochir Plast Chir ; 37(6): 365-74, 2005 Dec.
Article in German | MEDLINE | ID: mdl-16388451

ABSTRACT

A regular tissue functioning requires the adequate supply of oxygen and nutrient via blood vessels. The sequences of formation and maturation of vessels are initiated and maintained by different growth factors. The VEGF growth factor plays an exceptional role in these mechanisms. The creation of sublethal ischemia as an angiogenic stimulus known as "Delay" is a well established procedure in plastic surgery, although the underlying molecular biological mechanisms still remain unknown. The important role of VEGF and its regulation depending on oxygen pressure suggest a strong connection between this growth factor and the delay phenomenon. The VEGF concentration in skin and underlying muscle was measured in overdimensioned random pattern flaps on 32 male Sprague-Dawley rats after either VEGF gene therapy or circumcision without elevation of the flap and compared to controls. Additional random pattern flaps were raised seven days post gene therapy or delay. The effect on the flap perfusion was measured postoperatively using Indocyanine green Laser Fluoroscopy and the size of the surviving and necrotic areas of the flaps were analysed. The skin of the random pattern flaps showed both in the Delay group and in the VEGF gene therapy group a significantly elevated VEGF concentration compared to the controls. The underlying rectus abdominis muscle showed no significant differences in VEGF concentration between the groups. The flap perfusion postoperatively was significantly increased solely in the VEGF gene therapy group. The analysis of the surviving area of the flaps showed a significant increase over the controls in the gene therapy group. The Delay procedure results in a significantly and locally raised concentration of the VEGF growth factor. The gene therapeutical use of this growth factor allows us to raise flap perfusion and to reduce necrosis. Both VEGF gene therapy and Delay seem to promote similar mechanisms whereas the gene therapy produced superior results in this setting.


Subject(s)
Gene Transfer Techniques , Genetic Therapy , Neovascularization, Physiologic/genetics , Surgical Flaps/blood supply , Vascular Endothelial Growth Factor A/genetics , Animals , Gene Expression/physiology , Male , Necrosis , Rats , Regional Blood Flow/physiology , Skin/blood supply , Skin/pathology , Time Factors , Tissue Survival/genetics
15.
Handchir Mikrochir Plast Chir ; 37(6): 375-82, 2005 Dec.
Article in English | MEDLINE | ID: mdl-16388452

ABSTRACT

Sufficient tissue blood perfusion is critical for wound healing and for reconstructions in plastic surgery. There is considerable interest in the use of therapeutic angiogenesis to improve survival of ischemic flaps and to improve wound healing. Several growth factors have been tested in experimental flap models. Clinically, angiogenic therapy has been extensively studied in cardiovascular ischemic diseases and several clinical studies are ongoing in human patients. Results from these cardiovascular trials will benefit the planning of clinical trials in the field of plastic surgery. Furthermore, the development of strategies for local and controlled induction of lymphangiogenesis will hopefully improve the treatment of edema.


Subject(s)
Gene Transfer Techniques , Neovascularization, Physiologic/genetics , Surgical Flaps/blood supply , Vascular Endothelial Growth Factor A/genetics , Animals , Gene Expression/physiology , Humans , Lymphangiogenesis/genetics , Receptors, Vascular Endothelial Growth Factor/genetics , Tissue Survival/genetics , Wound Healing/genetics
17.
Lancet ; 362(9383): 557-9, 2003 Aug 16.
Article in English | MEDLINE | ID: mdl-12932390

ABSTRACT

CONTEXT: Xenotransplantation with pig organs offers a medium-term solution to the shortage of organs available for clinical transplantation. The immunological barriers to xenotransplantation have been, and remain, formidable. In the early 1990s, the identification of Galalpha1,3Gal (Gal) as the main target for human xenoreactive (anti-pig) antibodies and the development of pigs transgenic for a human complement regulatory protein, decay-accelerating factor (hDAF), were major advances. The presence of hDAF on the vascular endothelium of pig organs provided some protection against complement-mediated hyperacute rejection. This protection, however, was short-lived, and, until recently, the longest median time for organ survival that had been achieved (with combinations of biological and pharmacological immunosuppressants) in a series of pig-to-primate organ transplants was under a month. STARTING POINT: Christopher McGregor and colleagues recently reported to the International Society of Heart and Lung Transplantation (J Heart Lung Transplant 2003; 22: S89) that, by combining the use of organs which express hDAF with the administration of a soluble Gal glycoconjugate and other immunosuppressive agents, the survival of pig hearts in baboons can be extended to a median of 76 days. McGregor's work suggests that immunological barriers to xenotransplantation are not insurmountable. WHERE NEXT? The recent generation of pigs that do not express Gal epitopes (alpha1,3-galactosyltransferase gene-knockout pigs) might remove the need both for the expression of hDAF and the administration of a soluble Gal glycoconjugate. The absence of a natural antibody response will allow investigation of the cellular immune response and of any molecular incompatibilities between pig and primate that may be detrimental to graft survival. Furthermore, the absence of a humoral response may open the way for the induction of immunological tolerance (or unresponsiveness in the absence of exogenous immunosuppression) to a transplanted pig organ.


Subject(s)
Transplantation, Heterologous/immunology , Transplantation, Heterologous/trends , Animals , Animals, Genetically Modified/immunology , CD55 Antigens/immunology , Forecasting , Graft Rejection/genetics , Graft Rejection/immunology , Humans , Immunosuppressive Agents/administration & dosage , Immunosuppressive Agents/pharmacology , Organ Transplantation/methods , Swine , Tissue Survival/drug effects , Tissue Survival/genetics , Tissue Survival/immunology , Transplantation Immunology/drug effects , Transplantation Immunology/genetics , Transplantation Immunology/immunology
18.
J Heart Lung Transplant ; 16(2): 231-9, 1997 Feb.
Article in English | MEDLINE | ID: mdl-9059935

ABSTRACT

BACKGROUND: Hyperacute rejection currently prevents clinical application of discordant lung xenografts. Pigs transgenic for human regulators of complement activation offer one promising potential solution to this problem. METHODS: Using fresh human blood in an ex vivo lung perfusion model, we studied eight different strains of pigs transgenic for human decay accelerating factor. Survival (by blood flow and gas transfer criteria) were correlated with immunohistologic evidence of pulmonary human decay accelerating factor expression and complement activation. RESULTS: With human blood perfusion, blood flow through the unmodified pig lung rapidly falls and is not restored by continuous infusion or high-dose bolus of prostacyclin. Airway pressure also rises rapidly and is followed promptly by loss of gas transfer. Four of the transgenic pig strains showed no difference from this pattern. Immunohistochemistry for human decay accelerating factor revealed low or no pulmonary expression in these lungs. In contrast, two of five transgenic pig lungs that had significant decay accelerating factor expression demonstrated recovery of pulmonary blood flow within 1 hour, and rejection was delayed, from less than 20 minutes in controls to about 1 hour. Complement activation, particularly the alternative pathway, was inhibited in lungs with high levels of endothelial decay accelerating factor expression. CONCLUSIONS: Lungs from some strains of pig transgenic for human decay accelerating factor demonstrate incomplete physiologic and histologic protection from hyperacute rejection. Although complement-independent pathogenic mechanisms may present a formidable obstacle, pig lungs transgenic for human complement regulatory proteins may facilitate discordant lung transplantation in human beings.


Subject(s)
Blood , CD55 Antigens/genetics , Graft Rejection/genetics , Lung Transplantation/immunology , Animals , Animals, Genetically Modified , Complement Activation/genetics , Complement Activation/immunology , Gene Expression/physiology , Graft Rejection/immunology , Graft Rejection/pathology , Humans , Immune Tolerance/genetics , Immune Tolerance/immunology , Lung/blood supply , Lung/pathology , Lung Transplantation/pathology , Perfusion , RNA, Messenger/genetics , Regional Blood Flow/physiology , Swine , Tissue Survival/genetics
19.
Urologe A ; 35(2): 127-35, 1996 Mar.
Article in German | MEDLINE | ID: mdl-8650846

ABSTRACT

Donor-recipient histocompatibility, as evaluated by the HLA matching results, plays an important role in the outcome of renal transplants, although much controversy surrounds the benefit of kidney allocation based on HLA typing. In this report HLA matching and survival data on 1,342 transplants performed at the University of California at San Francisco between 1984 and 1992 and treated uniformly by quadruple immunosuppression were analyzed in relation to the recipient's age. With respect to the influence of the increasing number of mismatches from 0 to 6, the analysis revealed decreasing 3-year graft survival rates as follows: 85.4%; 87.3%; 71.3%; 78.2%; 75.8%; 70.9% and 67.5%. Whereas the impact of cold ischemia time and histocompatibility was equally important during the 3-year postoperative period, the essential positive influence of good HLA matching on the long-term graft survival was demonstrated. The children aged between 5 and 18 years were identified as a high-risk group by the analysis, HLA-A incompatibility being attributed to poor graft survival in this age group. With respect to the effect of HLA-A histoincompatibility, the data provide evidence that HLA-A matching results seem to play an important role in graft survival in children, whereas transplants well matched in terms of HLA-B did well in adult recipients. No age difference in the impact of HLA-DR could be detected. In conclusion, HLA matching is still essential. It seems that there are differences in the impact of HLA loci in relation to the recipient's age.


Subject(s)
Histocompatibility Testing , Kidney Transplantation/physiology , Tissue Survival/genetics , Adolescent , Adult , Age Factors , Cadaver , Child , Child, Preschool , Female , Humans , Immunosuppression Therapy , Infant , Male , Middle Aged , Risk Factors
20.
Hum Genet ; 92(3): 265-8, 1993 Oct 01.
Article in English | MEDLINE | ID: mdl-8406434

ABSTRACT

Severe familial amyloid cardiomyopathy (FAC) in a Danish kindred is associated with a specific mutation (Met for Leu 111) in the transthyretin (TTR) gene. The mutation causes the loss of a DdeI restriction site in the gene, allowing molecular diagnostic studies. We studied formalin-fixed, paraffin-embedded tissues, up to 39 years old, from 29 family members of this kindred. DNA was partially purified from deparaffinized tissue sections and a DNA sequence of the TTR gene flanking the mutation site was amplified by the polymerase chain reaction (PCR), followed by restriction enzyme analysis. Amplified DNA was obtained from tissues representing 23 of the 29 persons. Ten out of the 23 family members were found to carry the TTR Met 111 mutation, whereas 13 were not affected. The results were consistent with known clinical data and with corresponding serum TTR examinations. This retrospective study shows that archival tissues can be used to confirm the diagnosis and disease pattern in members of families affected by hereditary diseases.


Subject(s)
Amyloidosis/genetics , Cardiomyopathies/genetics , Methionine/genetics , Prealbumin/genetics , Tissue Survival/genetics , Adolescent , Adult , Aged , Aged, 80 and over , Amyloidosis/diagnosis , Cardiomyopathies/diagnosis , Child, Preschool , DNA-Cytosine Methylases , Denmark , Female , Formaldehyde , Humans , Leucine/genetics , Male , Middle Aged , Oligodeoxyribonucleotides/genetics , Paraffin Embedding , Point Mutation , Polymerase Chain Reaction , Retrospective Studies , Tissue Fixation
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