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1.
Cell ; 164(1-2): 183-196, 2016 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-26771491

RESUMEN

Proper establishment of synapses is critical for constructing functional circuits. Interactions between presynaptic neurexins and postsynaptic neuroligins coordinate the formation of synaptic adhesions. An isoform code determines the direct interactions of neurexins and neuroligins across the synapse. However, whether extracellular linker proteins can expand such a code is unknown. Using a combination of in vitro and in vivo approaches, we found that hevin, an astrocyte-secreted synaptogenic protein, assembles glutamatergic synapses by bridging neurexin-1alpha and neuroligin-1B, two isoforms that do not interact with each other. Bridging of neurexin-1alpha and neuroligin-1B via hevin is critical for the formation and plasticity of thalamocortical connections in the developing visual cortex. These results show that astrocytes promote the formation of synapses by modulating neurexin/neuroligin adhesions through hevin secretion. Our findings also provide an important mechanistic insight into how mutations in these genes may lead to circuit dysfunction in diseases such as autism.


Asunto(s)
Astrocitos/metabolismo , Proteínas de Unión al Calcio/metabolismo , Moléculas de Adhesión Celular Neuronal/metabolismo , Proteínas de la Matriz Extracelular/metabolismo , Moléculas de Adhesión de Célula Nerviosa/metabolismo , Tálamo/metabolismo , Animales , Células COS , Chlorocebus aethiops , Predominio Ocular , Humanos , Ratones , Ratones Noqueados , Enfermedades del Sistema Nervioso/metabolismo , Neuronas/metabolismo , Isoformas de Proteínas/metabolismo , Transducción de Señal , Sinapsis/metabolismo
2.
Mol Psychiatry ; 28(11): 4642-4654, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37730842

RESUMEN

Dopamine (DA) neurons in the ventral tegmental area (VTA) promote social brain functions by releasing DA onto nucleus accumbens neurons, but it remains unclear how VTA neurons communicate with cortical neurons. Here, we report that the medial prefrontal cortex (mPFC)-lateral hypothalamus (LH)-VTA pathway contributes to social deficits in mice with IRSp53 deletion restricted to cortical excitatory neurons (Emx1-Cre;Irsp53fl/fl mice). LH-projecting mutant mPFC neurons display abnormally increased excitability involving decreased potassium channel gene expression, leading to excessive excitatory synaptic input to LH-GABA neurons. A circuit-specific IRSp53 deletion in LH-projecting mPFC neurons also increases neuronal excitability and induces social deficits. LH-GABA neurons with excessive mPFC excitatory synaptic input show a compensatory decrease in excitability, weakening the inhibitory LHGABA-VTAGABA pathway and subsequently over-activating VTA-GABA neurons and over-inhibiting VTA-DA neurons. Accordingly, optogenetic activation of the LHGABA-VTAGABA pathway improves social deficits in Emx1-Cre;Irsp53fl/fl mice. Therefore, the mPFC-LHGABA-VTAGABA-VTADA pathway contributes to the social deficits in Emx1-Cre;Irsp53fl/fl mice.


Asunto(s)
Área Hipotalámica Lateral , Área Tegmental Ventral , Animales , Ratones , Dopamina/metabolismo , Neuronas Dopaminérgicas/metabolismo , Ácido gamma-Aminobutírico/metabolismo , Área Hipotalámica Lateral/metabolismo , Núcleo Accumbens/metabolismo , Área Tegmental Ventral/metabolismo
3.
BMC Infect Dis ; 24(1): 1, 2024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-38166696

RESUMEN

BACKGROUND: As the population acquires immunity through vaccination and natural infection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), understanding the intrinsic severity of coronavirus disease (COVID-19) is becoming challenging. We aimed to evaluate the intrinsic severity regarding circulating variants of SARS-CoV-2 and to compare this between vaccinated and unvaccinated individuals. METHODS: With unvaccinated and initially infected confirmed cases of COVID-19, we estimated the case severity rate (CSR); case fatality rate (CFR); and mortality rate (MR), including severe/critical cases and deaths, stratified by age and compared by vaccination status according to the period regarding the variants of COVID-19 and vaccination. The overall rate was directly standardized with age. RESULTS: The age-standardized CSRs (aCSRs) of the unvaccinated group were 2.12%, 5.51%, and 0.94% in the pre-delta, delta, and omicron period, respectively, and the age-standardized CFRs (aCFRs) were 0.60%, 2.49%, and 0.63% in each period, respectively. The complete vaccination group had lower severity than the unvaccinated group over the entire period showing under 1% for the aCSR and 0.5% for the aCFR. The age-standardized MR of the unvaccinated group was 448 per million people per month people in the omicron period, which was 11 times higher than that of the vaccinated group. In terms of age groups, the CSR and CFR sharply increased with age from the 60 s and showed lower risk reduction in the 80 s when the period changed to the omicron period. CONCLUSIONS: The intrinsic severity of COVID-19 was the highest in the delta period, with over 5% for the aCSR, whereas the completely vaccinated group maintained below 1%. This implies that when the population is vaccinated, the impact of COVID-19 will be limited, even if a new mutation appears. Moreover, considering the decreasing intrinsic severity, the response to COVID-19 should prioritize older individuals at a higher risk of severe disease.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/epidemiología , COVID-19/prevención & control , Mutación , Conducta de Reducción del Riesgo , Vacunación
4.
Lasers Med Sci ; 38(1): 262, 2023 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-37947906

RESUMEN

Many patients demand minimally invasive treatments for skin rejuvenation, such as nonablative laser and superficial chemical peels. Combination therapy yet has not been studied histopathologically. The purpose of this study is to assess the histopathological efficacy of a 1927-nm thulium laser-assisted salicylic acid (SA) peel in skin rejuvenation. A six-segment table was drawn on the shaved back of C57BL/6 mouse. All segments were irradiated with the thulium laser-different tips and passes were used for specific segments. A 30% SA peel was then applied to the right-hand segments. After treatment, the skin samples were collected from each segment and examined for dermal thickness, collagen density, and melanin content. Greater thickness was seen in the combination therapy group compared with the laser alone group and in those segments receiving more passes with larger beam-sized tip. Collagen density increased in all treated skin segments, irrespective of the group. No adverse events were noted in the treated areas. The sample size was small and mouse skin has histological differences with human skin. The combination of a thulium laser and 30% SA peel has a synergistic effect on dermal thickness, so that can be suggested as a novel skin rejuvenation technique.


Asunto(s)
Terapia por Láser , Envejecimiento de la Piel , Animales , Ratones , Humanos , Tulio , Rejuvenecimiento , Ratones Endogámicos C57BL , Terapia por Láser/efectos adversos , Colágeno , Modelos Animales de Enfermedad
5.
Int J Mol Sci ; 24(22)2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-38003257

RESUMEN

The continuous emergence of new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants with multiple spike (S) protein mutations pose serious threats to current coronavirus disease 2019 (COVID-19) therapies. A comprehensive understanding of the structural stability of SARS-CoV-2 variants is vital for the development of effective therapeutic strategies as it can offer valuable insights into their potential impact on viral infectivity. S protein mediates a virus' attachment to host cells by binding to angiotensin-converting enzyme 2 (ACE2) through its receptor-binding domain (RBD), and mutations in this protein can affect its stability and binding affinity. We analyzed S protein structural stability in various Omicron subvariants computationally. Notably, the S protein sequences analyzed in this work were obtained directly from our own sample collection. We evaluated the binding free energy between S protein and ACE2 in several complex forms. Additionally, we measured distances between the RBD of each chain in S protein to analyze conformational changes. Unlike most of the prior studies, we analyzed full-length S protein-ACE2 complexes instead of only RBD-ACE2 complexes. Omicron subvariants including BA.1, BA.2, BA.2.12.1, BA.4/BA.5, BA.2.75, BA.2.75_K147E, BA.4.6 and BA.4.6_N658S showed enhanced stability compared to wild type, potentially due to distinct S protein mutations. Among them, BA.2.75 and BA.4.6_N658S exhibited the highest and lowest level of stability, respectively.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , Enzima Convertidora de Angiotensina 2 , Mutación , Unión Proteica , SARS-CoV-2/genética , Glicoproteína de la Espiga del Coronavirus/genética
6.
Emerg Infect Dis ; 28(3): 756-759, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35107418

RESUMEN

To clarify transmissibility of the severe acute respiratory syndrome coronavirus 2 Omicron variant, we determined serial intervals and secondary attack rates among household contacts in South Korea. Mean serial interval for 12 transmission pairs was 2.9 days, and secondary attack rate among 25 households was 50.0%, raising concern about a rapid surge in cases.


Asunto(s)
COVID-19 , Composición Familiar , SARS-CoV-2 , Intervalo de Infección en Serie , COVID-19/epidemiología , COVID-19/transmisión , Humanos , República de Corea/epidemiología
7.
Emerg Infect Dis ; 28(2): 415-419, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35076365

RESUMEN

We report the rapid emergence of severe acute respiratory syndrome coronavirus 2 lineages B.1.619 and B.1.620 in South Korea. The surge in frequency in a relatively short time emphasizes the need for ongoing monitoring for new lineages to track potential increases in transmissibility and disease severity and reductions in vaccine efficacy.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , República de Corea/epidemiología , Eficacia de las Vacunas
8.
Emerg Infect Dis ; 28(4): 898-900, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35171760

RESUMEN

In South Korea, a November 2021 outbreak caused by severe acute respiratory syndrome coronavirus 2 Omicron variant originated from 1 person with an imported case and spread to households, kindergartens, workplaces, restaurants, and hospitals, resulting in 11 clusters within 3 weeks. An epidemiologic curve indicated rapid community transmission of the Omicron variant.


Asunto(s)
COVID-19 , SARS-CoV-2 , COVID-19/epidemiología , Brotes de Enfermedades , Humanos , República de Corea/epidemiología
9.
Cancer ; 128(4): 778-787, 2022 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-34705268

RESUMEN

BACKGROUND: Immune checkpoint inhibitors (ICIs) have shown significant improvements in patients with advanced non-small cell lung cancer (NSCLC). One of the major issues with ICIs is determining the optimal treatment duration. METHODS: This multicenter, retrospective study analyzed clinical outcomes in patients with NSCLC who completed 2 years of ICI therapy or were treated for more than 6 months and then discontinued ICIs without disease progression at 11 medical centers in Korea between August 2017 and December 2020. RESULTS: Ninety-six patients who completed 2 years of ICIs were reviewed. The median durations of treatment and follow-up were 24.0 and 33.9 months, respectively. The objective response rate (ORR) was 85.4%. The median progression-free survival (PFS) and overall survival (OS) periods were not reached. After completion, the PFS and OS rates were 81.1% and 96.4%, respectively, at 12 months. Forty-three patients were identified who discontinued ICIs without disease progression: 26 (60.5%) for adverse events and 17 (39.5%) for other causes. The median durations of treatment and follow-up were 10.5 and 21.2 months, respectively. The ORR was 90.7%. The median PFS and OS periods were not reached. After discontinuation, the PFS and OS rates were 71.0% and 90.0%, respectively, at 12 months. CONCLUSIONS: A significantly high proportion of patients who completed 2 years of ICI therapy continued to experience long-term PFS. Even if ICIs are discontinued after 6 months in patients without disease progression, they may achieve a durable response and facilitate long-term survival. LAY SUMMARY: The optimal treatment duration for immune checkpoint inhibitors (ICIs) remains to be determined. This study reports the long-term outcomes of patients with non-small cell lung cancer who completed 2 years of ICI therapy or achieved a durable response after the discontinuation of ICIs without disease progression in real-world practice. A significantly high proportion of patients who completed 2 years of ICIs continued to experience long-term progression-free survival. In addition, even if ICIs are discontinued after 6 months in patients without disease progression, they may achieve a durable response and facilitate long-term survival.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Carcinoma de Pulmón de Células no Pequeñas/patología , Progresión de la Enfermedad , Humanos , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Neoplasias Pulmonares/patología , Estudios Retrospectivos
10.
Cancer Immunol Immunother ; 71(4): 967-978, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34988585

RESUMEN

Human epidermal growth factor receptor type 2 (HER2)-positive breast cancer that is treated with anti-HER2/neu monoclonal antibody (mAb) is not free from late recurrences. Addition of anti-4-1BB mAb to anti-HER2/neu mAb has been demonstrated to strengthen the cytotoxic antitumor response. Our study expands on this by revealing the influence of anti-4-1BB mAb addition on the immune memory of anti-HER2/neu mAb. We designed murine breast cancer models by implanting TUBO and TUBO-P2J cell lines in mice, which were then treated with anti-HER2/neu and/or anti-4-1BB mAb. After complete surgical and/or chemical regression of the tumor, the mice were rechallenged with a second injection of cancer cells. Notably, anti-HER2/neu and anti-4-1BB mAb combination therapy had a synergistic antitumor effect at the initial treatment. However, the combination therapy did not evoke immune memory, allowing the tumors to thrive at rechallenge with reduced CD44+ expression in CD8+ T cells. Immune memory was also impaired when anti-4-1BB mAb was administered to naive CD8+ T cells but was sustained when this was administered to activated CD8+ T cells. In an attempt to resist the loss of immune memory, we controlled the dose of anti-4-1BB mAb to optimize the stimulation of activated CD8+ T cells. Immune memory was achieved with the dose regulation of anti-4-1BB mAb to 1 mg/kg in our model. Our study demonstrates the importance in understanding the adaptive immune mechanism of anti-HER2/neu and anti-4-1BB mAb combination therapy and suggests a dose optimization strategy is necessary to ensure development of successful immune memory.


Asunto(s)
Linfocitos T CD8-positivos , Neoplasias Mamarias Experimentales , Animales , Anticuerpos Monoclonales/farmacología , Anticuerpos Monoclonales/uso terapéutico , Femenino , Memoria Inmunológica , Neoplasias Mamarias Experimentales/patología , Ratones , Miembro 9 de la Superfamilia de Receptores de Factores de Necrosis Tumoral
11.
PLoS Pathog ; 16(1): e1008288, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31961911

RESUMEN

Insects rely on the innate immune system for defense against pathogens, some aspects of which are under hormonal control. Here we provide direct experimental evidence showing that the juvenile hormone-binding protein (mJHBP) of Aedes aegypti is required for the regulation of innate immune responses and the development of mosquito blood cells (hemocytes). Using an mJHBP-deficient mosquito line generated by means of CRISPR-Cas9 gene editing technology we uncovered a mutant phenotype characterized by immunosuppression at the humoral and cellular levels, which profoundly affected susceptibility to bacterial infection. Bacteria-challenged mosquitoes exhibited significantly higher levels of septicemia and mortality relative to the wild type (WT) strain, delayed expression of antimicrobial peptides (AMPs), severe developmental dysregulation of embryonic and larval hemocytes (reduction in the total number of hemocytes) and increased differentiation of the granulocyte lineage. Interestingly, injection of recombinant wild type mJHBP protein into adult females three-days before infection was sufficient to restore normal immune function. Similarly, injection of mJHBP into fourth-instar larvae fully restored normal larval/pupal hemocyte populations in emerging adults. More importantly, the recovery of normal immuno-activation and hemocyte development requires the capability of mJHBP to bind JH III. These results strongly suggest that JH III functions in mosquito immunity and hemocyte development in a manner that is perhaps independent of canonical JH signaling, given the lack of developmental and reproductive abnormalities. Because of the prominent role of hemocytes as regulators of mosquito immunity, this novel discovery may have broader implications for the understanding of vector endocrinology, hemocyte development, vector competence and disease transmission.


Asunto(s)
Aedes/crecimiento & desarrollo , Aedes/inmunología , Proteínas Portadoras/inmunología , Proteínas de Insectos/inmunología , Aedes/genética , Aedes/microbiología , Animales , Proteínas Portadoras/genética , Femenino , Hemocitos/inmunología , Hemocitos/microbiología , Inmunidad Innata , Proteínas de Insectos/genética , Hormonas Juveniles/inmunología , Larva/genética , Larva/crecimiento & desarrollo , Larva/inmunología , Larva/microbiología , Masculino , Serratia marcescens/fisiología
12.
J Med Virol ; 94(4): 1717-1722, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34862628

RESUMEN

As the coronavirus disease 2019 (COVID-19) pandemic continues, reinfection is likely to become increasingly common. However, confirming COVID-19 reinfection is difficult because it requires whole-genome sequencing of both infections to identify the degrees of genetic differences. Since the first reported case of reinfection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in the Republic of Korea in April 2020, four additional cases were classified as suspected reinfection cases. We performed whole-genome sequencing of viral RNA extracted from swabs obtained at the initial infection and reinfection stages of these four suspected cases. The interval between initial infection and reinfection of all four suspected cases was more than 3 months. All four patients were young (10-29 years), and they displayed mild symptoms or were asymptomatic during the initial infection and reinfection episodes. The analysis of genome sequences combined with the epidemiological results revealed that only two of the four cases were confirmed as reinfection, and both were reinfected with the Epsilon variant. Due to the prolonged COVID-19 pandemic, the possibility of reinfections with SARS-CoV-2 variants is increasing, as reported in our study. Therefore, continuous monitoring of cases is necessary.


Asunto(s)
COVID-19/virología , Genoma Viral/genética , Reinfección/virología , SARS-CoV-2/genética , Adolescente , Adulto , COVID-19/epidemiología , Femenino , Genómica , Humanos , Masculino , Mutación , Filogenia , ARN Viral/genética , Reinfección/epidemiología , República de Corea/epidemiología , SARS-CoV-2/aislamiento & purificación
13.
Lasers Surg Med ; 54(2): 281-288, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34298588

RESUMEN

BACKGROUND AND OBJECTIVES: Lasers are known to be the most effective treatment modality for pigmentary skin diseases. However, melanocytes and melanin pigment often recur or leave post-inflammatory hyperpigmentation after the laser procedure. Studies have reported on the role of progenitor cells in pigment cell regeneration, which can be constantly replenished through mitosis. However, the response of unpigmented melanocyte progenitor cells to laser treatment is poorly understood. In this study, we used adult zebrafish skin as the melanocyte regenerative system and examined the response of melanocyte progenitor cells to laser photothermolysis. MATERIALS AND METHODS: The two groups of adult zebrafish were irradiated with 1064 nm wavelength laser system of Q-switched neodymium:yttrium-aluminum-garnet (Nd:YAG) laser with 0.3 or 0.7 J·cm-2 . We compared the regeneration of pigment at different energy levels by measuring new melanocyte counts and pigment area. We traced and quantitatively compared the melanocyte lineage cells by immunohistochemical staining using specific markers such as sox10, mitfa, and dct during the regeneration process. Three repetitive laser ablations were also held to test the postinflammatory hyperpigmentation. RESULTS: After the laser ablation of melanocytes, most of the new melanocytes appeared between Days 5 and 10. In high-energy irradiation of 0.7 J·cm-2 , the unpigmented mitfa-expressing cells showed significant decrease (p < 0.05) and showed delay in the differentiation process of melanocyte lineage cells. After repeated laser irradiation, hyperpigmentation did not appear and the final recovery ratio of the pigmented area was 87.5% and 75.3% at the 0.3 and 0.7 J·cm-2 energy levels, respectively. CONCLUSION: We suggest that laser treatment overcoming the recurrence should be planned based on the adequate energy level targeting the melanocyte progenitor cells. High-energy irradiation may induce apoptosis of progenitor cells and delay their process of differentiation. Short-term repetitive sessions of laser therapy can reduce the pigmentation in the long-term observation.


Asunto(s)
Hiperpigmentación , Láseres de Estado Sólido , Terapia por Luz de Baja Intensidad , Animales , Hiperpigmentación/etiología , Hiperpigmentación/cirugía , Láseres de Estado Sólido/uso terapéutico , Melanocitos , Pigmentación , Células Madre , Pez Cebra
14.
J Korean Med Sci ; 36(50): e346, 2021 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-34962117

RESUMEN

In November 2021, 14 international travel-related severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) B.1.1.529 (omicron) variant of concern (VOC) patients were detected in South Korea. Epidemiologic investigation revealed community transmission of the omicron VOC. A total of 80 SARS-CoV-2 omicron VOC-positive patients were identified until December 10, 2021 and 66 of them reported no relation to the international travel. There may be more transmissions with this VOC in Korea than reported.


Asunto(s)
COVID-19/transmisión , SARS-CoV-2 , Enfermedad Relacionada con los Viajes , Adulto , Anciano , Anciano de 80 o más Años , COVID-19/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , República de Corea/epidemiología , Adulto Joven
15.
Int J Mol Sci ; 22(11)2021 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-34200331

RESUMEN

The coronavirus disease 2019 (COVID-19) has caused a large global outbreak. It is accordingly important to develop accurate and rapid diagnostic methods. The polymerase chain reaction (PCR)-based method including reverse transcription-polymerase chain reaction (RT-PCR) is the most widely used assay for the detection of SARS-CoV-2 RNA. Along with the RT-PCR method, digital PCR has emerged as a powerful tool to quantify nucleic acid of the virus with high accuracy and sensitivity. Non-PCR based techniques such as reverse transcription loop-mediated isothermal amplification (RT-LAMP) and reverse transcription recombinase polymerase amplification (RT-RPA) are considered to be rapid and simple nucleic acid detection methods and were reviewed in this paper. Non-conventional molecular diagnostic methods including next-generation sequencing (NGS), CRISPR-based assays and nanotechnology are improving the accuracy and sensitivity of COVID-19 diagnosis. In this review, we also focus on standardization of SARS-CoV-2 nucleic acid testing and the activity of the National Metrology Institutes (NMIs) and highlight resources such as reference materials (RM) that provide the values of specified properties. Finally, we summarize the useful resources for convenient COVID-19 molecular diagnostics.


Asunto(s)
Prueba de Ácido Nucleico para COVID-19/métodos , COVID-19/diagnóstico , Técnicas de Amplificación de Ácido Nucleico/métodos , SARS-CoV-2/aislamiento & purificación , Animales , COVID-19/virología , Sistemas CRISPR-Cas , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Técnicas de Diagnóstico Molecular , Nanotecnología , Reacción en Cadena de la Polimerasa , ARN Viral , Recombinasas , Transcripción Reversa , Sensibilidad y Especificidad
16.
Nanotechnology ; 31(12): 12LT01, 2020 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-31739301

RESUMEN

We proposed a dislocation sink technology for achieving Si1-x Ge x multi-bridge-channel field-effect-transistor beyond 5 nm transistor design-rule that essentially needs an almost crystalline-defect-free Si1-x Ge x channel. A generation of a dislocation sink via H+ implantations in a strain-relaxed Si0.7Ge0.3 layer grown on a Si substrate and a following annealing almost annihilate completely misfit and threading dislocations located near the interface between a relaxed Si0.7Ge0.3 layer and a Si substrate. A real-time (continuous heating from room temperature to 600 °C) in situ high-resolution-transmission-electron-microscopy and inverse-fast-Fourier-transform image observation at 1.25 MV acceleration voltage obviously demonstrated the annihilation process between dislocation sinks and remaining misfit and threading dislocations during a thermal annealing, called the [SiI or GeI + V Si or V Ge â†’ Si1-x Ge x ] annihilation process, where SiI, GeI, V Si, and V Ge are interstitial Si, interstitial Ge, Si vacancy, and Ge vacancy, respectively. In particular, the annihilation process efficiency greatly depended on the dose of H+ implantation and annealing temperature; i.e. a maximum annihilation process efficiency achieved at 5 × 1015 atoms cm-2 and 800 °C.

17.
Eur Neurol ; 83(1): 111-120, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32344406

RESUMEN

BACKGROUND: The purpose of this study was to identify the top 100 cited articles dedicated to sleep medicine published in journals that have made key contributions to the field. METHODS: We performed a search of journals and selected 100 top-cited articles by utilizing the Institute for Scientific Information database available under the banner of the Web of Science. Next, we manually reviewed the contents of the top 100 cited articles. We examined the characteristics of the articles, such as the number of citations, ranking, authorship, article title, year of publication, publishing journal, publication type, and topic categories. RESULTS: The top-cited articles were published in 49 journals, and the most frequently cited journal was Sleep (23 articles). The top 100 cited articles originated from institutions in 9 countries, with the USA contributing 67 articles. The institution associated with the largest numbers of sleep medicine citation classics was Stanford University (11 articles). Morin CM, who was the first author for 6 articles, was listed most frequently in the sleep medicine citation classics. The publication years were concentrated in the 2000s, when 42 articles were published. The topics included 35 insomnia studies, 25 sleep physiology studies, 22 obstructive sleep apnea studies, and 19 other studies. CONCLUSIONS: The present study provides a detailed list of the most-cited articles on sleep medicine. This currently relevant approach provides an opportunity to recognize the classic articles on sleep, to provide useful insights into international leaders, and to describe research trends in the field of sleep medicine.


Asunto(s)
Bibliometría , Neurología , Sueño , Humanos
18.
Lasers Surg Med ; 52(10): 1010-1019, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32383204

RESUMEN

BACKGROUND AND OBJECTIVES: Many light and radiofrequency-based rejuvenation devices have claimed to increase collagen production in the skin dermal tissue. However, there has not been enough scientific evidence to prove whether the result is just a profibrotic response or not. We aimed to find the optimal skin rejuvenation device that shows true neocollagenesis. STUDY DESIGN/MATERIALS AND METHODS: We evaluated dermal collagen thickness and gene expression of procollagen type 1, 3, matrix metalloproteinase-3 (MMP-3), and transforming growth factor-ß (TGF-ß) resulting from different energy-based devices in a rat model in vivo. The wound-healing response was evaluated histologically and by real-time polymerase chain reaction (RT-PCR) at immediate, 1st, 2nd, 4th, 8th, and 12th week after the initial procedure. RESULTS: At the 12th week, the most relevant changes of the dermal thickness were found in specimens after treatment with electrosurgical unit, fractional CO2 and 1064 nm Q-switched Nd:YAG. Procollagen 1 and 3 were also found to be the highest in electrosurgical unit, fractional CO2 , and microneedle radiofrequency. Dramatic changes of MMP-3 and TGF-ß were remarkable at the early observation but went back to normal level at 12th week. The ratio of procollagen 1 and 3 was found to be the lowest with Q-Switched Nd:YAG 1064 nm and fractional CO2 . CONCLUSION: Electrosurgical unit resulted in most significant changes, but due to irreversible thermal damage and extremely high procollagen results it is considered as a profibrotic response. Fractional CO2 and Q-Switched Nd:YAG 1064 nm are applicable to face skin rejuvenation treatment considering thickening of dermal tissue and lower procollagen 1:3 ratio similar to the neocollagenesis purpose. Lasers Surg. Med. © 2020 Wiley Periodicals LLC.


Asunto(s)
Láseres de Estado Sólido , Envejecimiento de la Piel , Animales , Colágeno , Ratas , Rejuvenecimiento , Piel , Cicatrización de Heridas
19.
J Cosmet Laser Ther ; 22(3): 141-145, 2020 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-32436411

RESUMEN

Xanthelasma palpebrarum (XP) does not regress spontaneously and most patients complain of cosmetic discomfort. This study presents the results of treatment of XP using 1,444 nm Nd:YAG laser. We aim to evaluate the clinical efficacy of a 1,444 nm Nd:YAG laser in XP. Twenty-eight patients with XP treated with 1,444 nm Nd:YAG laser were analyzed retrospectively. A physician scored the results based on the reduction of the initial lesion area under six categories. The results were scored as follows: no effect (0% clearing of xanthelasma area), some response (1-24% clearing), moderate response (25-49% clearing), marked response (50-74% clearing), satisfactory result (75-99% clearing), and excellent result (100% clearing). Twelve patients (42.8%) showed excellent clearance and 10 patients (35.7%) had clearance greater than 75%. Overall, 24 patients (85.7%) showed improvement higher than 50%. Half of the patients (14 patients) ended the treatment with satisfactory results with one treatment session. Including seven patients who ended the treatment after two laser sessions, 21 patients (75%) reported satisfactory results and ended the treatment after 1 to 2 laser sessions. XP treatment with 1,444 nm Nd:YAG laser showed promising results. We believe it can be an effective and safe treatment modality for XP.


Asunto(s)
Terapia por Láser , Láseres de Estado Sólido , Neoplasias Cutáneas , Xantomatosis , Humanos , Láseres de Estado Sólido/uso terapéutico , Estudios Retrospectivos , Neoplasias Cutáneas/cirugía , Resultado del Tratamiento , Xantomatosis/cirugía
20.
J Cosmet Laser Ther ; 22(6-8): 244-252, 2020 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-33957852

RESUMEN

Background: As filler injections have become very common procedures worldwide, the number of complications has increased. However, there is a lack of systematized studies and precise classification of late and delayed complications. This study aimed to suggest new and reliable classifications and to characterize the clinical manifestations of late and delayed complications after filler injections.Methods: This retrospective study analyzed patients and suggested a new classification of delayed adverse effects related to filler injection. Several demographic and clinical findings were analyzed. Patients were classified into two types according to their clinical presentation: Type I (Localized) or Type II (Generalized).Results: Twenty-five patients were evaluated during a clinically active adverse event suspected to be related to fillers. The most common injected filler substance was hyaluronic acid (HA, 68.8%). 76% of the patients were classified with Localized complications. In the Generalized complications group, systemic symptoms were more common (p=0.002), the treatment response was poor (p=0.010), and fewer patients showed complete remission (p=0.007) than in the Localized complications group.Conclusions: We propose a simple new classification method for late and delayed complications after dermal filler: Localized and Generalized. We expect that this new classification could help provide appropriate treatment and predict patient prognosis.


Asunto(s)
Técnicas Cosméticas , Rellenos Dérmicos , Técnicas Cosméticas/efectos adversos , Rellenos Dérmicos/efectos adversos , Humanos , Ácido Hialurónico/efectos adversos , Estudios Retrospectivos
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