141 research outputs found

    Coordinating Stem Cell Behavior in the Hair Follicle

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    Tissue stem cells perform important functions throughout an organismā€™s life. They generate new cells to replenish cells that are lost during normal wear and tear or in response to acute injury. Remarkably, hair follicles naturally undergo repetitive cycles of regeneration and degeneration, a process that is accomplished with the support of stem cells within the hair follicles. It is this feature that makes this miniorgan an attractive model system to study stem cell biology. Interestingly, hair follicle is home to two distinct stem cell populations: epithelial hair follicle stem cells (HFSCs), which contribute to the formation of hair shafts, and melanocyte stem cells (McSCs), which contribute to hair pigmentation. During the hair cycle, HFSCs and McSCs work in harmony to generate a pigmented hair. However, little is known about the inter-stem-cell crosstalk governing this intricate coordination. To identify candidate transcription factors that specify HFSCs in mouse, the gene expression profiles of the HFSCs residing in the bulge of hair follicles versus the epithelial basal cells outside the bulge were compared. One of the ā€œmolecular signatureā€ genes being upregulated in the HFSCs is nuclear factor I/B (Nfib). Embryonic ablation of Nfib revealed that Nfib is required for the hair follicle morphogenesis and hair folliclemediated re-epithelization during wound repair. Meanwhile, to address the function of Nfib in established HFSCs, I conditionally induced Nfib ablation in the adult HFSCs. Interestingly, I found that the ablation of Nfib in the adult HFSCs did not perturb the HFSC maintenance, as the growth of hair follicles and the hair cycle proceeded relatively normally. Instead, and even more unexpected, NFIB loss in the HFSCs promoted the proliferation and precocious differentiation of their nearby McSCs. These findings provide new insights into how McSC and HFSC behaviors maintain reliance upon cooperative factors within the hair follicle and how this might be uncoupled in injury, stress and disease states

    Thoracic aorta pseudoaneurysm with hemopericardium: unusual presentation of warfarin overdose

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    There have been few case reports which discuss a relationship between warfarin overdose and aortic pseudoaneurysm leakage. We report the case of a female receiving warfarin who presented with dsypnea. Her international normalized ratio was > 10. Chest radiograph revealed cardiomegaly, and chest computed tomography (CT) showed a bulging pouch-like lesion below the aortic arch greater than 6x6 cm in size and a fluid collection suggesting blood in the pericardium. Thoracic endovascular aneurysm repair (TEVAR) was successfully performed by a cardiovascular surgeon. Aortic pseudoaneurysm formation and leakage may be considered as a rare complication in patients receiving warfarin therapy. Further study regarding warfarin use and the incidence of pseudoaneurysm leakage is needed

    Ring Chromosome 7 Presenting with Intrauterine Growth Restriction and Multiple Anomalies

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    SummaryObjectiveRing chromosome 7 is a very rare chromosomal anomaly that may have a grave prognosis. Nevertheless, the clinical features associated with ring chromosome 7 are highly variable. Here, we report a case with ring chromosome 7 and the perinatal findings.Case ReportA 32-year-old, gravida 1, para 0, woman was referred to our hospital because of intrauterine growth restriction (IUGR) and oligohydramnios at 35 weeks of gestation. Prenatal ultrasound revealed a severe IUGR fetus presenting with multicystic kidney, hydronephrosis and oligohydramnios. At parturition, the birth weight of this male infant was 1,720 g, and a battery of anomalies were also noted, including imperforate anus, hypospadia, micropenis, right cryptorchidism, severe IUGR, multiple nevi on the forehead, shoulder and left thigh, brain atrophy, right multicystic kidney, and left mild hydronephrosis. Cytogenetic study from cord blood revealed a ring chromosome 7.ConclusionRing chromosome 7 is extremely rare and our case might be the 15th and youngest case in the medical literature. Our case had multicystic kidney and imperforate anus, which have not been reported previously. Prenatal diagnosis of ring chromosome 7 is very difficult. When fetuses present with severe IUGR, oligohydramnios and multicystic kidney, chromosomal aberrations should be kept in mind, and perinatal cytogenetic workup is warranted

    Effects of Dipeptidyl Peptidase-4 Inhibition with MK-0431 on Syngeneic Mouse Islet Transplantation

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    Dipeptidyl peptidase (DPP)-4 inhibitors increase circulating levels of glucagon-like peptide-1 and glucose-dependent insulinotropic polypeptide which may promote Ī²-cell proliferation and survival. This study tested if DPP-4 inhibition with MK-0431 is beneficial for diabetic mice syngeneically transplanted with a marginal number of islets. We syngeneically transplanted 150ā€‰C57BL/6 mouse islets under the kidney capsule of each streptozotocin-diabetic mouse and then treated recipients with (n=21) or without (n=17) MK-0431 (30ā€‰mg/kg/day, po) for 6 weeks. After islet transplantation, blood glucose levels decreased in both MK-0431-treated and control groups. However, the blood glucose and area under the curve of the intraperitoneal glucose tolerance test at 2, 4, and 6 weeks were not significantly different between MK-0431-treated mice and controls. During 6 weeks, both groups exhibited increased body weights over time. However, the weight between two groups did not differ throughout the study period. At 6 weeks after transplantation, the graft beta-cell mass (0.024 Ā± 0.005 versus 0.023 Ā± 0.007ā€‰mg, P=0.8793) and insulin content (140 Ā± 48 versus 231 Ā± 63ā€‰ng, P=0.2939) were comparable in the MK-0431-treated group and controls. Our results indicate posttransplant DPP-4 inhibition with MK-0431 in the diabetic recipient with a marginal number of islets is not beneficial to transplantation outcome or islet grafts

    Pulmonary function change in patients with Sauropus androgynus-related obstructive lung disease 15 years later

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    Background/PurposeLittle is understood about the clinical course and prognosis of patients with Sauropus androgynus-related obstructive lung disease. The aim of this study was to investigate their clinical manifestations and pulmonary function change 15 years after the acute episode.MethodsA descriptive, observational study of patients with S androgynus-related obstructive lung disease, diagnosed 15 years ago, was conducted. We evaluated their pulmonary function and the Modified Medical Research Council (MMRC) dyspnea scale. Saint Georgeā€™s Respiratory Questionnaire (SGRQ) was also performed. Age- and forced expiratory volume in one second (FEV1)-matched chronic obstructive pulmonary disease (COPD) patients were used as a reference group for comparison of clinical manifestations.ResultsTwenty-nine of 49 patients, diagnosed at our hospital 15 years ago, could be contacted. Four patients died and one patient was ventilator-dependent. Sixteen patients were willing to come to our hospital to have pulmonary function and questionnaire evaluation. The FEV1 of these patients declined only 1.6Ā Ā±Ā 21.6Ā mL/year over a 15-year period. Meanwhile, the severity of their dyspnea and their health-related quality of life were better than age- and FEV1-matched COPD patients as shown by the MMRC dyspnea scale (1.4Ā Ā±Ā 0.8 vs. 2.0Ā Ā±Ā 1.0; pĀ =Ā 0.037) and symptom domain of the SGRQ (32.6Ā Ā±Ā 18.4 vs. 43.5Ā Ā±Ā 20.3; pĀ =Ā 0.006).ConclusionAfter an acute deterioration, patients with S androgynus-related obstructive lung disease had a stationary pulmonary function over a period of 15 years, and their clinical manifestations were less severe than age- and FEV1-matched COPD patients. A further study with a larger sample size may be needed to confirm these findings

    Myocardium-derived conditioned medium improves left ventricular function in rodent acute myocardial infarction

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    <p>Abstract</p> <p>Background</p> <p>We investigated whether myocardium-derived conditioned medium (MDCM) is effective in preserving left ventricular (LV) function in a rat acute myocardial infarction (AMI) model.</p> <p>Methods</p> <p>Adult male Sprague-Dawley (SD) rats (n = 36) randomized to receive either left coronary artery ligation (AMI induction) or thoracotomy only (sham procedure) were grouped as follows (n = 6 per group): Group I, II, and III were sham-controls treated by fresh medium, normal rat MDCM, and infarct-related MDCM, respectively. Group IV, V, and VI were AMI rats treated by fresh medium, normal MDCM, and infarct-related MDCM, respectively. Either 75 Ī¼L MDCM or fresh medium was administered into infarct myocardium, followed by intravenous injection (3 mL) at postoperative 1, 12, and 24 h.</p> <p>Results</p> <p>In vitro studies showed higher phosphorylated MMP-2 and MMP-9, but lower Ī±-smooth muscle actin and collagen expressions in neonatal cardiac fibroblasts treated with MDCM compared with those in the cardiac fibroblasts treated with fresh medium (all p < 0.05). Sirius-red staining showed larger collagen deposition area in LV myocardium in Group IV than in other groups (all p < 0.05). Stromal cell-derived factor-1Ī± and CXCR4 protein expressions were higher in Group VI than in other groups (all p < 0.05). The number of von Willebrand factor- and BrdU-positive cells and small vessels in LV myocardium as well as 90-day LV ejection fraction were higher, whereas oxidative stress was lower in Group VI than in Group IV and Group V (all p < 0.05).</p> <p>Conclusion</p> <p>MDCM therapy reduced cardiac fibrosis and oxidative stress, enhanced angiogenesis, and preserved 90-day LV function in a rat AMI model.</p

    Enhanced plasmonic biosensor utilizing paired antibody and label-free Fe3O4 nanoparticles for highly sensitive and selective detection of Parkinsonā€™s Ī±-synuclein in serum

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    Parkinsonā€™s disease (PD) is an acute and progressive neurodegenerative disorder, and diagnosis of the disease at its earliest stage is of paramount importance to improve the life expectancy of patients. Ī±-Synuclein (Ī±-syn) is a potential biomarker for the early diagnosis of PD, and there is a great need to develop a biosensing platform that precisely detects Ī±-syn in human body fluids. Herein, we developed a surface plasmon resonance (SPR) biosensor based on the label-free iron oxide nanoparticles (Fe3O4 NPs) and paired antibody for the highly sensitive and selective detection of Ī±-syn in serum samples. The sensitivity of the SPR platform is enhanced significantly by directly depositing Fe3O4 NPs on the Au surface at a high density to increase the decay length of the evanescent field on the Au film. Moreover, the utilization of rabbit-type monoclonal antibody (Ī±-syn-RmAb) immobilized on Au films allows the SPR platform to have a high affinity-selectivity binding performance compared to mouse-type monoclonal antibodies as a common bioreceptor for capturing Ī±-syn molecules. As a result, the current platform has a detection limit of 5.6 fg/mL, which is 20,000-fold lower than that of commercial ELISA. The improved sensor chip can also be easily regenerated to repeat the Ī±-syn measurement with the same sensitivity. Furthermore, the SPR sensor was applied to the direct analysis of Ī±-syn in serum samples. By using a format of paired Ī±-syn-RmAb, the SPR sensor provides a recovery rate in the range from 94.5% to 104.3% to detect the Ī±-syn in diluted serum samples precisely. This work demonstrates a highly sensitive and selective quantification approach to detect Ī±-syn in human biofluids and paves the way for the future development in the early diagnosis of PD

    Differential Proteomic Analysis of Human Placenta-Derived Mesenchymal Stem Cells Cultured on Normal Tissue Culture Surface and Hyaluronan-Coated Surface

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    Our previous results showed that hyaluronan (HA) preserved human placenta-derived mesenchymal stem cells (PDMSC) in a slow cell cycling mode similar to quiescence, the pristine state of stem cells in vivo, and HA was found to prevent murine adipose-derived mesenchymal stem cells from senescence. Here, stable isotope labeling by amino acid in cell culture (SILAC) proteomic profiling was used to evaluate the effects of HA on aging phenomenon in stem cells, comparing (1) old and young passage PDMSC cultured on normal tissue culture surface (TCS); (2) old passage on HA-coated surface (CHA) compared to TCS; (3) old and young passage on CHA. The results indicated that senescence-associated protein transgelin (TAGLN) was upregulated in old TCS. Protein CYR61, reportedly senescence-related, was downregulated in old CHA compared to old TCS. The SIRT1-interacting Nicotinamide phosphoribosyltransferase (NAMPT) increased by 2.23-fold in old CHA compared to old TCS, and is 0.48-fold lower in old TCS compared to young TCS. Results also indicated that components of endoplasmic reticulum associated degradation (ERAD) pathway were upregulated in old CHA compared to old TCS cells, potentially for overcoming stress to maintain cell function and suppress senescence. Our data points to pathways that may be targeted by HA to maintain stem cells youth

    Early combined treatment with sildenafil and adipose-derived mesenchymal stem cells preserves heart function in rat dilated cardiomyopathy

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    <p>Abstract</p> <p>Background</p> <p>We investigated whether early combined autologous adipose-derived mesenchymal stem cell (ADMSC) and sildenafil therapy offers an additive benefit in preserving heart function in rat dilated cardiomyopathy (DCM).</p> <p>Methods</p> <p>Adult Lewis rats (n = 8 per group) were divided into group 1 (normal control), group 2 (saline-treated DCM rats), group 3 [2.0 Ɨ 10<sup>6 </sup>ADMSC implanted into left ventricular (LV) myocardium of DCM rats], group 4 (DCM rats with sildenafil 30 mg/kg/day, orally), and group 5 (DCM rats with combined ADMSC-sildenafil). Treatment was started 1 week after DCM induction and the rats were sacrificed on day 90.</p> <p>Results</p> <p>The results showed that mitochondrial protein expressions of connexin43 and cytochrome-C were lowest in group 2, and lower in groups 3 and 4 than in group 5 (p < 0.002). Conversely, oxidative index was highest in group 2, and also higher in groups 3 and 4 than in group 5 (p < 0.0003). The mRNA expressions of interleukin (IL)-10, Gro/IL-8, endothelial nitric oxide synthase, and Bcl-2 were lowest in group 2, and lower in groups 3 and 4 compared with group 5 (p < 0.0001). The mRNA expressions of matrix metalloproteinase-9, Bax, caspase 3, and stromal-cell derived factor-1Ī± were highest in group 2, and higher in groups 3 and 4 than in group 5 (p < 0.0004). Apoptosis and fibrosis in LV myocardium were most prominent in group 2 and higher in groups 3 and 4 than in group 5, whereas angiogenesis and LV ejection fraction were lowest in group 2 and lower in groups 3 and 4 than in group 5 (p < 0.003).</p> <p>Conclusion</p> <p>Early combined ADMSC/sildenafil is superior to either treatment alone in preserving LV function.</p
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