Human stem cells have been isolated from embryos as well as diverse somatic tissues. Much efforts have been made to apply those stem cells for therapeutic purpose. Molecular dissection of "stemness" and differentiation process will provide us a clue to further understanding of stem cell biology. The fate of stem cell is determined in part by internal regulation mediated by transcriptional control. A set of genes related to specific functions might be expressed and suppressed upon external or internal signaling. Therefore, it is necessary to identify the complete gene expression profile that defines the stem cell. Moreover, we should verify the potential of therapeutic stem cells regarding differentiation, specific function, tumorigenecity, and toxicity rigorously before the clinical application. At present we have only limited information on "stemness" and differentiation into specific lineages. In the genome era, we can draw a molecular portrait on these functional and morphologic changes along the differentiation, trans-differentiation as well as de-differentiation using the DNA chip technology. We need to accumulate database for gene expression at various steps of stem cell differentiation, which will enhance our knowledge for research on and medical application of stem cell.
Biology ; Embryonic Structures ; Gene Expression ; Gene Expression Profiling ; Genome ; Genomics ; Humans ; Oligonucleotide Array Sequence Analysis ; Stem Cells* ; Transcriptome

No abstract available.
Breast Neoplasms* ; Breast* ; Drug Resistance, Multiple* ; Genes, MDR*

Intentional delay of aftercoming siblings in multiple gestation is an infrequent occurrence in obstetrics. After delivery of an immature twin, conventional treatment calls for induction and delivery of the aftercoming sibling. However, several case reports have documented the feasibility of an expectant management. And also, as in our case, an aggressive treatment consisting of cerclage, tocolysis, and broad-spectrum antibiotics has been shown to prolong pregnancy. We experienced an unavoidable delivery of a nonviable first twin after premature rupture of membranes at 16 weeks' of gestation. The placenta was left undisturbed. Twin B was confirmed to be alive within the intact second sac. Tocolysis was started and cervical cerclage was done directly after delivery of twin A. Pregnancy was successfully prolonged, which enabled the second fetus to remain in utero and grow for another 145 days. To our knowledge, this was the longest interval between deliveries in a twin pregnancy reported in the literature. A healthy 3,050 gm male was delivered by cesarean section at 37 weeks' of gestation. Below we present this case in detail and discussed with respect to the aggressive approach undertaken to prolong gestation.
Anti-Bacterial Agents ; Cerclage, Cervical ; Cesarean Section ; Female ; Fetus ; Humans ; Male ; Membranes ; Obstetrics ; Placenta ; Pregnancy* ; Pregnancy, Twin ; Rupture ; Siblings ; Tocolysis ; Twins*

Neurogenesis occurs during embryonic development and continues throughout adulthood. Although spontaneous adult neurogenesis is restricted to selective germinal regions, including the subventricular zone and dentate gyrus of the hippocampus, neural stem cells (NSCs) are widely distributed in the central and peripheral nervous systems. Besides their ability to integrate into existing neural networks during physiological conditions, NSCs also proliferate and differentiate in response to injury, thus promising the potential use of endogenous NSCs for the treatment of neuropathological conditions. In this review, we discuss recent progress in the understanding of adult neurogenesis in the brain and peripheral nervous system.
Adult ; Adult Stem Cells ; Brain ; Central Nervous System ; Dentate Gyrus ; Embryonic Development ; Female ; Hippocampus ; Humans ; Neural Stem Cells ; Neurogenesis ; Peripheral Nervous System ; Pregnancy

BACKGROUND: Several antibiotics can be used to treat ventilator-associated pneumonia caused by carbapenem-resistant A. baumannii (CRAB-VAP) including high-dose sulbactam. However, the effectiveness of high-dose sulbactam therapy is not well known. We report our experience with high-dose sulbactam for treatment of CRAB-VAP. METHODS: Medical records of patients with CRAB-VAP who were given high-dose sulbactam between May 2013 and June 2015 were reviewed. RESULTS: Fifty-eight patients with CRAB-VAP were treated with high-dose sulbactam. The mean age was 72.0 ± 15.2 years, and the acute physiology and chronic health evaluation II (APACHE II) score was 15.1 ± 5.10 at the time of CRAB-VAP diagnosis. Early clinical improvement was observed in 65.5% of patients, and 30-day mortality was 29.3%. Early clinical failure (odds ratio [OR]: 8.720, confidence interval [CI]: 1.346-56.484; p = 0.023) and APACHE II score ≥ 14 at CRAB-VAP diagnosis (OR: 10.934, CI: 1.047-114.148; p = 0.046) were associated with 30-day mortality. CONCLUSIONS: High-dose sulbactam therapy may be effective for the treatment of CRAB-VAP. However, early clinical failure was observed in 35% of patients and was associated with poor outcome.
Acinetobacter baumannii* ; Acinetobacter* ; Anti-Bacterial Agents ; APACHE ; Diagnosis ; Humans ; Medical Records ; Mortality ; Pneumonia, Ventilator-Associated* ; Sulbactam*

No abstract available.
Pheochromocytoma* ; Pregnancy*

Recently, many hospitals have been adopting clinical data warehouses (CDW) as well as electronic medical records. These new hospital information systems are inevitably introducing very large amounts of clinical data that might be useful for further analysis. However, the electronic clinical data in the CDW are usually byproducts of clinical practice rather than the product of research. Therefore, they include inconsistent and sometimes erroneous information that might not have the specific context of the clinical situations. Data miners usually have various academic backgrounds such as electronics, informatics, statistics, biomedicine, and public health. If the complex situations surrounding the clinical data are not well understood, investigators performing data mining in clinical fields may have problems assessing the information they are confronted with. Here, we would like to introduce some basic concepts on the principles of data mining in clinical fields including legal and ethical considerations as well as technical concerns.
Machine Learning ; Data Mining ; Electronic Health Records ; Electronics ; Electrons ; Hospital Information Systems ; Humans ; Informatics ; Public Health ; Research Personnel

PURPOSE: To estimate the utility of the enhanced ectasia display mode of Pentacam in discriminating keratoconus and keratoconus suspect from normal cornea. METHODS: Corneal topography was measured using the Pentacam in keratoconus, keratoconus suspect and a normal control group. A best-fit sphere (BFS) and an enhanced best-fit sphere (EBFS) were used as reference surfaces for corneal elevation measurements, and measured values from both the anterior and posterior surfaces were compared among the three groups. Receiver operating characteristic (ROC) curves were used to identify the optimal posterior corneal elevation cutoff points for maximal sensitivity and specificity in discriminating keratoconus and keratoconus suspect from the normal control group. RESULTS: Mean anterior and posterior corneal elevation were statistically higher in keratoconus than in keratoconus suspect and normal corneas. The optimal cutoff point of posterior elevation was 23 micrometer for the keratoconus group, and this value was associated with a sensitivity and a specificity of 96.7% and 98.6%, respectively for keratoconus. The optimal cutoff point of enhanced posterior elevation was 43 micrometer for the keratoconus group, and this value was associated with a sensitivity and a specificity of 96.7% and 95.5%, respectively. CONCLUSIONS: The enhanced ectasia display mode showed similar diagnostic power to that of the conventional elevation map, and the former could be more useful in a clinical setting due to the pronounced visualization of corneal elevation.
Cornea ; Corneal Topography ; Dilatation, Pathologic ; Keratoconus ; Mass Screening ; ROC Curve ; Sensitivity and Specificity

BACKGROUND: Human metapneumovirus (hMPV) is a relatively recently identified respiratory virus that induces respiratory symptoms similar to those of respiratory syncytial virus infection in children. The characteristics of hMPV-infected adults are unclear because few cases have been reported. METHODS: We conducted a retrospective review of hospitalized adult patients with a positive multiplex real-time polymerase chain reaction assay result from 2012 to 2016 at a single tertiary referral hospital in South Korea. We analyzed clinical characteristics of the enrolled patients and divided patients into an acute respiratory distress syndrome (ARDS) group and a non-ARDS group. RESULTS: In total, 110 adults were reviewed in this study. Their mean age was 61.4 years, and the majority (n = 105, 95.5%) had comorbidities or were immunocompromised. Most of the patients had pneumonia on chest X-ray (n = 88, 93.6%), 22 (20.0%) had ARDS, and 12 (10.9%) expired during hospitalization. The mortality rate for patients with ARDS was higher than that of the other patients (36.4% vs. 5.7%, P = 0.001). The risk factor for hMPV-associated ARDS was heart failure (odds ratio, 5.24; P = 0.044) and laboratory values were increased blood urea nitrogen and increased C-reactive protein. The acquisition site of infection was divided into community vs. nosocomial; 43 patients (39.1%) had a nosocomial infection. The risk factors for nosocomial infection were an immunocompromised state, malignancy and immunosuppressive treatment. CONCLUSIONS: These data suggest that hMPV is one of the important respiratory pathogens important respiratory pathogen that causes pneumonia/ARDS in elderly, immunocompromised individuals and that it may be transmitted via the nosocomial route.
Adult* ; Aged ; Blood Urea Nitrogen ; C-Reactive Protein ; Child ; Comorbidity ; Cross Infection ; Heart Failure ; Hospitalization ; Humans* ; Korea ; Metapneumovirus* ; Mortality* ; Pneumonia ; Real-Time Polymerase Chain Reaction ; Respiratory Distress Syndrome, Adult* ; Respiratory Syncytial Viruses ; Retrospective Studies* ; Risk Factors ; Tertiary Care Centers ; Thorax

Retinal pigment epithelial cells(RPE) from a monolayer on the outer portion of sensory retina and have important physiologic functions that include solute transport, phagocytiosis and digestion of membrances shed from photoreceptor outer segments, and drug detoxication. Recently, transplantation of normal RPE has been proposed as a potential therapeutic modality in the surgical management of subretinal neovascularization in age related macular degeneration(ARMD). The viability of RPE at the time of transplantation is important for a good result after transplantation. This viability can be influenced by the period and environmental conditions of storage after harvest.In this study, the influence of these two factors on the viability was evaluated under controlling other remaining factors in vitro. And limitation of masimal time and optimal environmental conditions of storage were investigated.From November 1997 to February 1998, RPE cell sheets from six donor eyeballs for corneal transplantation in the department of ophthalmology of Severance Hospital were harvested and stored in -70degrees C, 4degrees C, or room temperature condotion. The viability of RPE cells at 0, 24 and 48 hours after havest was assessed and compared statistically.The viability was highest at 4degrees C condition. During storage, the viability was about 95% at 24 hours for and decreased abruptly to below 90% at 48 hours. Therefore, RPE cells for transplantation are to be stored at 4degrees C condition and transplantation should be performed within 24 hours after harvest.
Corneal Transplantation ; Digestion ; Epithelial Cells* ; Humans* ; Macular Degeneration ; Ophthalmology ; Retina ; Retinaldehyde* ; Tissue Donors*