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1.
Mol Psychiatry ; 28(9): 3717-3726, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37773447

RESUMEN

There are no studies investigating topological properties of resting-state fMRI (rs-fMRI) in patients who have recovered from psychosis and discontinued medication (hereafter, recovered patients [RP]). This study aimed to explore topological organization of the functional brain connectome in the RP using graph theory approach. We recruited 30 RP and 50 age and sex-matched healthy controls (HC). The RP were further divided into the subjects who were relapsed after discontinuation of antipsychotics (RP-R) and who maintained recovered state without relapse (RP-M). Using graph-based network analysis of rs-fMRI signals, global and local metrics and hub information were obtained. The robustness of the network was tested with random failure and targeted attack. As an ancillary analysis, Network-Based Statistic (NBS) was performed. Association of significant findings with psychopathology and cognitive functioning was also explored. The RP showed intact network properties in terms of global and local metrics. However, higher global functional connectivity strength and hyperconnectivity in the interconnected component were observed in the RP compared to HC. In the subgroup analysis, the RP-R were found to have lower global efficiency, longer characteristic path length and lower robustness whereas no such abnormalities were identified in the RP-M. Associations of the degree centrality of some hubs with cognitive functioning were identified in the RP-M. Even though network properties of the RP were intact, subgroup analysis revealed more altered topological organizations in the RP-R. The findings in the RP-R and RP-M may serve as network biomarkers for predicting relapse or maintained recovery after the discontinuation of antipsychotics.


Asunto(s)
Antipsicóticos , Conectoma , Trastornos Psicóticos , Humanos , Antipsicóticos/uso terapéutico , Encéfalo/diagnóstico por imagen , Imagen por Resonancia Magnética , Trastornos Psicóticos/tratamiento farmacológico , Recurrencia
2.
Mol Psychiatry ; 28(3): 1201-1209, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36494461

RESUMEN

Schizophrenia (SZ) is associated with an increased risk of life-long cognitive impairments, age-related chronic disease, and premature mortality. We investigated evidence for advanced brain ageing in adult SZ patients, and whether this was associated with clinical characteristics in a prospective meta-analytic study conducted by the ENIGMA Schizophrenia Working Group. The study included data from 26 cohorts worldwide, with a total of 2803 SZ patients (mean age 34.2 years; range 18-72 years; 67% male) and 2598 healthy controls (mean age 33.8 years, range 18-73 years, 55% male). Brain-predicted age was individually estimated using a model trained on independent data based on 68 measures of cortical thickness and surface area, 7 subcortical volumes, lateral ventricular volumes and total intracranial volume, all derived from T1-weighted brain magnetic resonance imaging (MRI) scans. Deviations from a healthy brain ageing trajectory were assessed by the difference between brain-predicted age and chronological age (brain-predicted age difference [brain-PAD]). On average, SZ patients showed a higher brain-PAD of +3.55 years (95% CI: 2.91, 4.19; I2 = 57.53%) compared to controls, after adjusting for age, sex and site (Cohen's d = 0.48). Among SZ patients, brain-PAD was not associated with specific clinical characteristics (age of onset, duration of illness, symptom severity, or antipsychotic use and dose). This large-scale collaborative study suggests advanced structural brain ageing in SZ. Longitudinal studies of SZ and a range of mental and somatic health outcomes will help to further evaluate the clinical implications of increased brain-PAD and its ability to be influenced by interventions.


Asunto(s)
Esquizofrenia , Adulto , Humanos , Masculino , Adolescente , Adulto Joven , Persona de Mediana Edad , Anciano , Femenino , Estudios Prospectivos , Imagen por Resonancia Magnética , Encéfalo/patología , Envejecimiento
3.
Opt Express ; 31(11): 18265-18273, 2023 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-37381540

RESUMEN

A III/V-on-Bulk-Si DFB laser with a long phase shift section optimized for single-mode stability is presented. The optimized phase shift allows stable single-mode operations up to 20 times a threshold current. This mode stability is achieved by a gain difference between fundamental and higher modes maximized by sub-wavelength-scale tuning of the phase shift section. In SMSR-based yield analyses, the long-phase-shifted DFB laser showed superior performance compared to the conventional λ/4-phase-shifted ones.

4.
Int J Neuropsychopharmacol ; 26(3): 207-216, 2023 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-36545813

RESUMEN

BACKGROUND: Brain age is a popular brain-based biomarker that offers a powerful strategy for using neuroscience in clinical practice. We investigated the brain-predicted age difference (PAD) in patients with schizophrenia (SCZ), first-episode schizophrenia spectrum disorders (FE-SSDs), and treatment-resistant schizophrenia (TRS) using structural magnetic resonance imaging data. The association between brain-PAD and clinical parameters was also assessed. METHODS: We developed brain age prediction models for the association between 77 average structural brain measures and age in a training sample of controls (HCs) using ridge regression, support vector regression, and relevance vector regression. The trained models in the controls were applied to the test samples of the controls and 3 patient groups to obtain brain-based age estimates. The correlations were tested between the brain PAD and clinical measures in the patient groups. RESULTS: Model performance indicated that, regardless of the type of regression metric, the best model was support vector regression and the worst model was relevance vector regression for the training HCs. Accelerated brain aging was identified in patients with SCZ, FE-SSDs, and TRS compared with the HCs. A significant difference in brain PAD was observed between FE-SSDs and TRS using the ridge regression algorithm. Symptom severity, the Social and Occupational Functioning Assessment Scale, chlorpromazine equivalents, and cognitive function were correlated with the brain PAD in the patient groups. CONCLUSIONS: These findings suggest additional progressive neuronal changes in the brain after SCZ onset. Therefore, pharmacological or psychosocial interventions targeting brain health should be developed and provided during the early course of SCZ.


Asunto(s)
Esquizofrenia , Humanos , Esquizofrenia/diagnóstico por imagen , Esquizofrenia/tratamiento farmacológico , Esquizofrenia Resistente al Tratamiento , Encéfalo , Envejecimiento/fisiología , Imagen por Resonancia Magnética/métodos
5.
BMC Neurosci ; 23(1): 5, 2022 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-35038994

RESUMEN

Previous deep learning methods have not captured graph or network representations of brain structural or functional connectome data. To address this, we developed the BrainNet-Global Covariance Pooling-Attention Convolutional Neural Network (BrainNet-GA CNN) by incorporating BrainNetCNN and global covariance pooling into the self-attention mechanism. Resting-state functional magnetic resonance imaging data were obtained from 171 patients with schizophrenia spectrum disorders (SSDs) and 161 healthy controls (HCs). We conducted an ablation analysis of the proposed BrainNet-GA CNN and quantitative performance comparisons with competing methods using the nested tenfold cross validation strategy. The performance of our model was compared with competing methods. Discriminative connections were visualized using the gradient-based explanation method and compared with the results obtained using functional connectivity analysis. The BrainNet-GA CNN showed an accuracy of 83.13%, outperforming other competing methods. Among the top 10 discriminative connections, some were associated with the default mode network and auditory network. Interestingly, these regions were also significant in the functional connectivity analysis. Our findings suggest that the proposed BrainNet-GA CNN can classify patients with SSDs and HCs with higher accuracy than other models. Visualization of salient regions provides important clinical information. These results highlight the potential use of the BrainNet-GA CNN in the diagnosis of schizophrenia.


Asunto(s)
Conectoma , Esquizofrenia , Encéfalo/diagnóstico por imagen , Conectoma/métodos , Humanos , Imagen por Resonancia Magnética/métodos , Redes Neurales de la Computación , Esquizofrenia/diagnóstico por imagen
6.
Psychol Med ; 52(14): 3193-3201, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-33588966

RESUMEN

BACKGROUND: Network approach has been applied to a wide variety of psychiatric disorders. The aim of the present study was to identify network structures of remitters and non-remitters in patients with first-episode psychosis (FEP) at baseline and the 6-month follow-up. METHODS: Participants (n = 252) from the Korean Early Psychosis Study (KEPS) were enrolled. They were classified as remitters or non-remitters using Andreasen's criteria. We estimated network structure with 10 symptoms (three symptoms from the Positive and Negative Syndrome Scale, one depressive symptom, and six symptoms related to schema and rumination) as nodes using a Gaussian graphical model. Global and local network metrics were compared within and between the networks over time. RESULTS: Global network metrics did not differ between the remitters and non-remitters at baseline or 6 months. However, the network structure and nodal strengths associated with positive-self and positive-others scores changed significantly in the remitters over time. Unique central symptoms for remitters and non-remitters were cognitive brooding and negative-self, respectively. The correlation stability coefficients for nodal strength were within the acceptable range. CONCLUSION: Our findings indicate that network structure and some nodal strengths were more flexible in remitters. Negative-self could be an important target for therapeutic intervention.


Asunto(s)
Trastornos Psicóticos , Humanos , Trastornos Psicóticos/psicología , Escalas de Valoración Psiquiátrica
7.
Knee Surg Sports Traumatol Arthrosc ; 29(11): 3724-3734, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33392699

RESUMEN

PURPOSE: To compare clinical outcomes between the conventional round and rectangular tunnel techniques in single-bundle posterior cruciate ligament (PCL) reconstruction. METHODS: Twenty-seven and 108 patients who underwent PCL reconstructions using a rectangular dilator (Group 1) and rounded tunnel reamer (Group 2), respectively, were included. The exclusion criteria were having a concomitant fracture, osteotomy, subtotal or total meniscectomy, and no remnant PCL tissue. A 4:1 propensity score matching was performed. The knee laxity on stress radiography, International Knee Documentation Committee Subjective Knee Evaluation score, Tegner activity score and Orthopädische Arbeitsgruppe Knie score were evaluated. RESULTS: No significant differences were found between the groups in terms of clinical scores. (n.s.) The mean posterior translations were also not significantly different between the Group 1 and 2 (3.6 ± 2.8 and 3.8. ± 3.1 mm, respectively; n.s.). However, 3 patients (11.1%) in Group 1 and 15 patients (13.8%) in Group 2 showed posterior translation of > 5 mm. The combined posterolateral corner sling technique was performed for 27 patients (100%) in Group 1 and for 96 patients (88.9%) in Group 2. We found no significant difference in rotational stability at the final follow-up. One patient was found to have a femoral condyle fracture during rectangular femoral tunnel establishment, which was healed after screw fixation, without laxity, during follow-up. The intra- and inter-observer reliabilities of the radiological measurements ranged from 0.81 to 0.89. CONCLUSION: Arthroscopic anatomical remnant-preserving PCL reconstruction using a rectangular dilator showed satisfactory clinical results and stability as compared with PCL reconstruction using a conventional rounded reamer. Rectangular tunnel technique in PCL reconstruction could be a good treatment option with theoretical advantage to be anatomic. LEVEL OF EVIDENCE: Level IV.


Asunto(s)
Traumatismos de la Rodilla , Reconstrucción del Ligamento Cruzado Posterior , Ligamento Cruzado Posterior , Estudios de Seguimiento , Humanos , Traumatismos de la Rodilla/cirugía , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/cirugía , Ligamento Cruzado Posterior/cirugía , Resultado del Tratamiento
8.
J Arthroplasty ; 36(7): 2523-2529, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33692000

RESUMEN

BACKGROUND: Despite the placement of acetabular components in the traditional "safe-zone", dislocations and all parts of the instability spectrum, including impingement, continue to be an issue. Recent research has established the importance of a degenerative spine and adverse pelvic mobility on functional acetabular orientation. The purpose of this study is to quantify the clinical consequences of a degenerative spine and adverse pelvic mobility on prosthetic impingement in patients undergoing total hip arthroplasty. METHODS: Between January 2018 and December 2019, a series of 1592 patients undergoing total hip arthroplasty had functional lateral radiographs and a computed tomography scan taken. Two spinal parameters and 2 pelvic mobility parameters were investigated for their association with impingement. Each patient was evaluated for anterior and posterior impingement, at all orientations within a traditional supine safe zone and a patient-specific functional safe zone. RESULTS: Patients with limited lumbar flexion (stiff spine), higher pelvic incidence-lumbar lordosis mismatch (sagittal imbalance), and more anterior pelvic mobility from stand to flexed-seated, exhibit increased anterior impingement. Patients with larger posterior pelvic mobility from supine-to-stand exhibited increased posterior impingement. Impingement was reduced 3-fold when the target cup orientation was tailored to a patient's functional safe zone rather than a generic target. Six percent of patients showed unavoidable impingement even with an optimized functional cup orientation. CONCLUSION: Our results support growing evidence that patients with a degenerative spine and adverse pelvic mobility are likely to have unfavorable functional cup orientations, resulting in prosthetic impingement. Preoperative functional radiographic screening is recommended to assess the likelihood of a patient experiencing impingement due to their unique spinopelvic mobility.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Acetábulo/diagnóstico por imagen , Acetábulo/cirugía , Artroplastia de Reemplazo de Cadera/efectos adversos , Articulación de la Cadera/diagnóstico por imagen , Articulación de la Cadera/cirugía , Humanos , Rango del Movimiento Articular , Columna Vertebral
9.
J Korean Med Sci ; 35(10): e64, 2020 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-32174063

RESUMEN

BACKGROUND: Individual particulate respirator use may offer protection against exposure to particulate matter < 2.5 µm in diameter (PM2.5). Among elderly Korean women, we explored individual particulate respirator use and cardiopulmonary function. METHODS: Recruited in Seoul, Korea, 21 elderly, non-smoking women wore particulate respirators for six consecutive days (exlcuding time spent eating, sleeping, and bathing). We measured resting blood pressure before, during, and after respirator use and recorded systolic and diastolic blood pressure, mean arterial blood pressure, pulse pressure, and lung function. We also measured 12-hour ambulatory blood pressure at the end of the 6-day long experiment and control periods. Additionally, we examined physiological stress (heart rate variability and urinary 8-hydroxy-2'-deoxyguanosine) while wearing the particulate respirators. Person- and exposure-level covariates were also considered in the model. RESULTS: After the 6-day period of respirator use, resting blood pressure was reduced by 5.3 mmHg for systolic blood pressure (P = 0.013), 2.9 mmHg for mean arterial blood pressure (P = 0.079), and 3.6 mmHg for pulse pressure (P = 0.024). However, particulate respirator use was associated with changes in physiological stress markers. A parasympathetic activity marker (high frequency) significantly decreased by 24.0% (P = 0.029), whereas a sympathetic activity marker (ratio of low-to-high frequency) increased by 50.3% (P = 0.045). An oxidative stress marker, 8-hydroxy-2'-deoxyguanosine, increased by 3.4 ng/mg creatinine (P = 0.021) during the experimental period compared with that during the control period. Lung function indices indicated that wearing particulate respirators was protective; however, statistical significance was not confirmed. CONCLUSION: Individual particulate respirator use may prevent PM2.5-induced blood-pressure elevation among elderly Korean women. However, the effects of particulate respirator use, including physiological stress marker elevation, should also be considered. TRIAL REGISTRATION: Clinical Research Information Service Identifier: KCT0003526.


Asunto(s)
Contaminantes Atmosféricos , Exposición a Riesgos Ambientales , Material Particulado , Dispositivos de Protección Respiratoria , Anciano , Presión Sanguínea , Monitoreo Ambulatorio de la Presión Arterial , Polvo , Exposición a Riesgos Ambientales/prevención & control , Femenino , Frecuencia Cardíaca , Humanos , República de Corea
10.
Clin Infect Dis ; 68(11): 1870-1876, 2019 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-30239615

RESUMEN

BACKGROUND: Although aminoglycosides are recommended for cavitary Mycobacterium avium complex lung disease (MAC-LD), the optimal duration of treatment is unclear. We investigated the association between duration of aminoglycoside treatment and outcomes in cavitary MAC-LD. METHODS: Among patients diagnosed with macrolide-susceptible cavitary MAC-LD between 2000 and 2013, 101 who received treatment up to August 2017 with a regimen containing aminoglycosides were enrolled at a tertiary referral center in South Korea. Their medical records were retrospectively reviewed. The duration of aminoglycoside treatment was at the discretion of the attending physician. RESULTS: A total of 75 patients (74.3%) were administered aminoglycosides for ≥3 months (median 164 days), whereas the remaining 26 patients (25.7%) received treatment for <3 months (median 59 days). The overall treatment success rate was 63.4% (64/101). Patients treated with aminoglycosides for ≥3 months had a significantly higher success rate than those treated for <3 months (69.3% vs 46.2%; P = .035). Multivariate analysis revealed that aminoglycoside treatment for ≥3 months was a significant factor for treatment success (adjusted odds ratio, 3.602; 95% confidence interval, 1.249-10.390; P = .018). Recurrence occurred in 8 (22.9%) of 35 patients who were followed up for at least 3 years after the end of treatment; all 8 patients received aminoglycosides for ≥3 months. CONCLUSIONS: Patients with cavitary MAC-LD treated with aminoglycosides for ≥3 months showed higher treatment success rate than those treated for <3 months. However, treatment for ≥3 months was not associated with the development of recurrence.


Asunto(s)
Aminoglicósidos/uso terapéutico , Antibacterianos/uso terapéutico , Duración de la Terapia , Enfermedades Pulmonares/tratamiento farmacológico , Infección por Mycobacterium avium-intracellulare/tratamiento farmacológico , Anciano , Femenino , Humanos , Enfermedades Pulmonares/microbiología , Masculino , Persona de Mediana Edad , Análisis Multivariante , Complejo Mycobacterium avium , Neumonía Bacteriana/tratamiento farmacológico , Recurrencia , República de Corea , Estudios Retrospectivos , Centros de Atención Terciaria/estadística & datos numéricos , Resultado del Tratamiento
11.
Artículo en Inglés | MEDLINE | ID: mdl-30012759

RESUMEN

Although it is known that the in vitro MICs of rifampin and ethambutol are poorly correlated with the clinical response in Mycobacterium avium complex (MAC) lung disease (MAC-LD), evidence for this is limited. This study investigated the association between treatment outcome and the in vitro MICs of rifampin and ethambutol in patients with MAC-LD. Among patients diagnosed with macrolide-susceptible MAC-LD between January 2008 and December 2013, 274 patients who were treated with a standard regimen for ≥12 months until August 2017 and whose in vitro MIC results were available were enrolled at a tertiary referral center in South Korea. The MICs of antimicrobial agents were determined using the broth microdilution method. The mean age of the included patients was 60.4 years. The overall treatment success rate was 79.6% (218/274 patients) and tended to decrease with increasing MICs of rifampin and ethambutol, particularly at MICs of ≥8 µg/ml. Treatment success rate was significantly different between MAC isolates with MICs of ≥8 µg/ml for rifampin and ethambutol and those with MICs of <8 µg/ml for rifampin and/or ethambutol (64.9% versus 85.3%, P < 0.001). Multivariate analysis showed that an MIC of ≥8 µg/ml for both drugs and initial sputum acid-fast bacillus (AFB) smear positivity were independent risk factors for an unfavorable response (adjusted odds ratio [OR] = 3.154, 95% confidence interval [CI] = 1.641 to 6.063, and P = 0.001 for an MIC of ≥8 µg/ml; adjusted OR = 2.769, 95% CI = 1.420 to 5.399, and P = 0.003 for initial sputum AFB smear positivity). These findings suggest that the in vitro MICs of rifampin and ethambutol may be related to treatment outcome in MAC-LD.


Asunto(s)
Antibacterianos/uso terapéutico , Etambutol/uso terapéutico , Enfermedades Pulmonares/tratamiento farmacológico , Complejo Mycobacterium avium/efectos de los fármacos , Rifampin/uso terapéutico , Adulto , Anciano , Femenino , Humanos , Enfermedades Pulmonares/microbiología , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Resultado del Tratamiento
12.
J Korean Med Sci ; 33(53): e342, 2018 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-30595683

RESUMEN

We validated the diagnostic performance of a previously developed blood-based 7-protein biomarker panel, AptoDetect™-Lung (Aptamer Sciences Inc., Pohang, Korea) using modified aptamer-based proteomic technology for lung cancer detection. Non-small cell lung cancer (NSCLC), 200 patients and benign nodule controls, 200 participants were enrolled. In a high-risk population corresponding to ≥ 55 years of age and ≥ 30 pack-years, the diagnostic performance was improved, showing 73.3% sensitivity and 90.5% specificity with an area under the curve of 0.88. AptoDetect™-Lung (Aptamer Sciences Inc.) offers the best validated performance to discriminate NSCLC from benign nodule controls in a high-risk population and could play a complementary role in lung cancer screening.


Asunto(s)
Biomarcadores de Tumor/sangre , Proteínas Sanguíneas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico , Neoplasias Pulmonares/diagnóstico , Adulto , Anciano , Área Bajo la Curva , Carcinoma de Pulmón de Células no Pequeñas/patología , Femenino , Humanos , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Curva ROC , República de Corea , Sensibilidad y Especificidad , Fumar
14.
Clin Infect Dis ; 63(11): 1449-1455, 2016 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-27609755

RESUMEN

BACKGROUND: We investigated the effects of corticosteroids on the 90-day mortality outcomes in patients with pulmonary tuberculosis who were admitted to the intensive care unit (ICU) because of acute respiratory failure (ARF). METHODS: The medical records of 124 patients who had pulmonary tuberculosis with ARF and were admitted to the ICU at our tertiary referral center in South Korea between March 1989 and December 2014 were retrospectively analyzed. The 90-day mortality rate in this population was analyzed after adjustments with the inverse probability of treatment weighted (IPTW) method. RESULTS: The mean patient age was 62 years, and the 90-day mortality rate was 49.2% (61/124). Adjuvant steroids were used in 70 (56.5%) patients. The 90-day mortality rate was similar irrespective of corticosteroid use (48.6%, steroid group; 50.0%, nonsteroid group). The use of adjuvant steroids was not associated with the unadjusted 90-day mortality (odds ratio [OR], 0.94; 95% confidence interval [CI], .46-1.92; P = .875). In a comparison using an adjusted IPTW approach of the 90-day mortality between the 2 groups, we found that corticosteroid use was independently associated with reduced 90-day mortality (OR, 0.47; 95% CI, .22-.98; P = .049). CONCLUSIONS: The study results showed that corticosteroids could reduce the 90-day mortality rate in critically ill pulmonary tuberculosis patients with ARF.


Asunto(s)
Corticoesteroides/uso terapéutico , Insuficiencia Respiratoria/complicaciones , Insuficiencia Respiratoria/mortalidad , Tuberculosis Pulmonar/tratamiento farmacológico , Tuberculosis Pulmonar/mortalidad , Corticoesteroides/administración & dosificación , Corticoesteroides/efectos adversos , Anciano , Enfermedad Crítica , Femenino , Humanos , Unidades de Cuidados Intensivos , Tiempo de Internación , Masculino , Registros Médicos , Persona de Mediana Edad , Mortalidad , Oportunidad Relativa , República de Corea/epidemiología , Insuficiencia Respiratoria/tratamiento farmacológico , Estudios Retrospectivos , Factores de Riesgo , Tuberculosis Pulmonar/epidemiología , Tuberculosis Pulmonar/microbiología
15.
Microb Ecol ; 69(2): 356-60, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25370886

RESUMEN

Relatively little is known of the archaeal communities associated with endolithic environments, compared to other microbial groups such as bacteria and fungi. Analyzing the pyrosequenced archaeal 16S ribosomal RNA (rRNA) gene V1-V3 region, we investigated the archaeal community associated with aboveground-exfoliated weathering layers of a granite gneiss, and of the saprolite derived from this rock at 1 m depth below the soil surface, in a forested hilly area south of Seoul, South Korea. In both these sites, an archaeal community dominated by the phylum Thaumarchaeota was identified. The archaeal community in all cases closely resembled that of the surface layer of acidic soils in temperate climates of Korea. It appears that there is no clear distinction in archaeal community composition between a soil and a rock and a saprolite despite a tremendous difference in the concentration of total nitrogen and organic carbon. Of the chemical properties we measured, pH was the best predictor of the archaeal community composition and relative abundance of thaumarchaeal subphyla. These findings reinforce the view that soil archaea are mostly generalists, whose ecology is not closely dependent on nitrogen concentration or soil organic matter status, the presence of living roots, or the abundant presence of any other biota.


Asunto(s)
Archaea/clasificación , Filogenia , Microbiología del Suelo , Archaea/genética , Archaea/aislamiento & purificación , Carbono/química , ADN de Archaea/genética , Genes Arqueales , Concentración de Iones de Hidrógeno , Nitrógeno/química , ARN Ribosómico 16S/genética , República de Corea , Análisis de Secuencia de ADN
16.
Respirology ; 20(1): 155-9, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25289945

RESUMEN

BACKGROUND AND OBJECTIVE: Although pulmonary arteriovenous malformations (PAVMs) are rare, they are important in clinical practice because they are associated with life-threatening complications such as brain abscess, stroke and lung haemorrhage. The aims of the present study were to characterize PAVMs in a Korean population and to examine the incidence and factors associated with cerebral complications, which are a major cause of mortality. METHODS: The medical records of patients with PAVMs between 2000 and 2013 were retrospectively reviewed. PAVMs were confirmed by enhanced chest computed tomography or by pulmonary angiography. RESULTS: Ninety patients (median age, 47.5 years; 81.8% female) with PAVMs were included. Twelve patients (13.3%) were clinically diagnosed with hereditary haemorrhagic telangiectasia (HHT) according to the Curacao criteria. Sixty-three patients underwent transcatheter embolization with no severe adverse events. Three patients required retreatment during a mean follow-up period of 3.3 years. Six and 14 patients suffered brain abscess or stroke, respectively, as a complication of PAVMs. These complications were not associated with the diameter of the arteries feeding the PAVMs (odds ratio, 1.106; 95% confidence interval, 0.895-1.366; P = 0.352) CONCLUSIONS: PAVMs are less associated with HHT in Koreans than in Western populations. Transcatheter embolization of PAVMs is safe and effective, and physicians need to consider treating the small arteries feeding PAVMs to prevent cerebral complications.


Asunto(s)
Fístula Arteriovenosa , Malformaciones Arteriovenosas , Arteria Pulmonar/anomalías , Venas Pulmonares/anomalías , Adulto , Anciano , Angiografía , Fístula Arteriovenosa/complicaciones , Fístula Arteriovenosa/diagnóstico , Fístula Arteriovenosa/epidemiología , Fístula Arteriovenosa/terapia , Malformaciones Arteriovenosas/complicaciones , Malformaciones Arteriovenosas/diagnóstico , Malformaciones Arteriovenosas/epidemiología , Malformaciones Arteriovenosas/terapia , Absceso Encefálico/epidemiología , Absceso Encefálico/etiología , Embolización Terapéutica/métodos , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , República de Corea/epidemiología , Estudios Retrospectivos , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/etiología , Telangiectasia Hemorrágica Hereditaria/epidemiología , Tomografía Computarizada por Rayos X
17.
J Korean Med Sci ; 30(1): 7-15, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25552878

RESUMEN

De-identification of personal health information is essential in order not to require written patient informed consent. Previous de-identification methods were proposed using natural language processing technology in order to remove the identifiers in clinical narrative text, although these methods only focused on narrative text written in English. In this study, we propose a regular expression-based de-identification method used to address bilingual clinical records written in Korean and English. To develop and validate regular expression rules, we obtained training and validation datasets composed of 6,039 clinical notes of 20 types and 5,000 notes of 33 types, respectively. Fifteen regular expression rules were constructed using the development dataset and those rules achieved 99.87% precision and 96.25% recall for the validation dataset. Our de-identification method successfully removed the identifiers in diverse types of bilingual clinical narrative texts. This method will thus assist physicians to more easily perform retrospective research.


Asunto(s)
Anonimización de la Información , Registros Electrónicos de Salud , Registros de Salud Personal , Algoritmos , Humanos , Multilingüismo , Procesamiento de Lenguaje Natural , Proyectos de Investigación
18.
Microb Ecol ; 67(4): 837-48, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24549745

RESUMEN

Little is known of the bacterial community of tropical rainforest leaf litter and how it might differ from temperate forest leaf litter and from the soils underneath. We sampled leaf litter in a similarly advanced stage of decay, and for comparison, we also sampled the surface layer of soil, at three tropical forest sites in Malaysia and four temperate forest sites in South Korea. Illumina sequencing targeting partial bacterial 16S ribosomal ribonucleic acid (rRNA) gene revealed that the bacterial community composition of both temperate and tropical litter is quite distinct from the soils underneath. Litter in both temperate and tropical forest was dominated by Proteobacteria and Actinobacteria, while soil is dominated by Acidobacteria and, to a lesser extent, Proteobacteria. However, bacterial communities of temperate and tropical litter clustered separately from one another on an ordination. The soil bacterial community structures were also distinctive to each climatic zone, suggesting that there must be a climate-specific biogeographical pattern in bacterial community composition. The differences were also found in the level of diversity. The temperate litter has a higher operational taxonomic unit (OTU) diversity than the tropical litter, paralleling the trend in soil diversity. Overall, it is striking that the difference in community composition between the leaf litter and the soil a few centimeters underneath is about the same as that between leaf litter in tropical and temperate climates, thousands of kilometers apart. However, one substantial difference was that the leaf litter of two tropical forest sites, Meranti and Forest Research Institute Malaysia (FRIM), was overwhelmingly dominated by the single genus Burkholderia, at 37 and 23 % of reads, respectively. The 454 sequencing result showed that most Burkholderia species in tropical leaf litter belong to nonpathogenic "plant beneficial" lineages. The differences from the temperate zone in the bacterial community of tropical forest litter may be partly a product of its differing chemistry, although the unvarying climate might also play a role, as might interactions with other organisms such as fungi. The single genus Burkholderia may be seen as potentially playing a major role in decomposition and nutrient cycling in tropical forests, but apparently not in temperate forests.


Asunto(s)
Bacterias/aislamiento & purificación , Biodiversidad , Bosques , Hojas de la Planta/microbiología , Microbiología del Suelo , Bacterias/clasificación , Bacterias/genética , Bacterias/crecimiento & desarrollo , ADN Bacteriano/genética , Malasia , Datos de Secuencia Molecular , ARN Ribosómico 16S/genética , República de Corea , Análisis de Secuencia de ARN , Clima Tropical
19.
Psychiatry Res ; 331: 115688, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38141265

RESUMEN

BACKGROUND: Investigating neural correlates in recovered patients with psychosis is important in terms of identifying biological markers associated with recovery status or predicting a possible future relapse. We sought to examine thalamic nuclei volumes and thalamus-centered functional connectivity (FC) in recovered patients with psychosis who discontinued their medication. METHODS: Thirty patients with psychosis who satisfied the criteria for full recovery and 50 healthy controls (HC) matched for age, sex, and education underwent magnetic resonance imaging and clinical evaluation. The recovered patients were divided into the maintained and relapsed subjects according to their clinical status on the follow-ups. Thalamic nuclei volumes and thalamus-centered FC were measured between the recovered patients and HC. Correlations between the thalamic nuclei or altered FC, and clinical symptoms and cognitive functioning were explored. RESULTS: Modest cognitive impairments and reduced thalamic nuclei volumes were evident in the recovered patients. Moreover, we found altered thalamo-cortical connectivity and its associations with negative symptoms and cognitive functioning in the recovered patients compared with HC. CONCLUSION: These findings suggest that there are still cognitive impairments, and aberrant neuronal changes in the recovered patients. The implication of differential FC patterns between the maintained and the relapsed patients remain to be further explored.


Asunto(s)
Disfunción Cognitiva , Trastornos Psicóticos , Humanos , Trastornos Psicóticos/complicaciones , Trastornos Psicóticos/diagnóstico por imagen , Trastornos Psicóticos/patología , Tálamo/diagnóstico por imagen , Imagen por Resonancia Magnética , Cognición , Vías Nerviosas/diagnóstico por imagen
20.
Neurosci Lett ; 804: 137239, 2023 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-37031942

RESUMEN

OBJECTIVES: Widespread changes in cortical thickness (CT) have been repeatedly reported in schizophrenia (SZ). The nature of the pathophysiologic process underlying such changes remains to be elucidated. The aims of the present study were to measure the CT; evaluate parent socioeconomic status (pSES), childhood trauma (ChT) and premorbid adjustment (PA) in patients with schizophrenia spectrum disorders (SSDs); and investigate group differences in CT (i.e., SSD vs. healthy controls (HCs)), pSES, PA, and/or ChT, as well as the interactions among these factors. METHODS: 164 patients with SSD and 245 age-, sex- and education-matched healthy controls have participated. The pSES, ChT and PA were evaluated using Korean version of Polyenvironmental Risk Score, Early Trauma Inventory Self Report-Short Form and Premorbid Adjustment Scale, respectively. Vertex-wise measure of CT was estimated using the FreeSurfer. To investigate the main effects and interactions, multilevel regression was employed. RESULTS: We found widespread cortical thinning in patients with SSDs compared to HCs. The cortical thinning was associated with ChT, symptom severity and chlorpromazine equivalent dose and duration of illness in patients. In multilevel regression, main effects of group and pSES and interaction between group and pSES were found whereas a significant interaction between ChT and CPZ equivalent was found in patients. CONCLUSION: Our findings indicate that compared to HCs, patients with SSDs have cortical structural abnormalities, and that group and pSES interaction determines CT. Further studies are needed to explore the effects of psychosocial factors on brain structural and functional abnormalities in SZ.


Asunto(s)
Esquizofrenia , Humanos , Esquizofrenia/diagnóstico por imagen , Adelgazamiento de la Corteza Cerebral , Encéfalo , Padres , Clorpromazina , Clase Social , Imagen por Resonancia Magnética , Corteza Cerebral/diagnóstico por imagen
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