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1.
Cell ; 185(24): 4541-4559.e23, 2022 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-36334588

RESUMO

The encoding of touch in the spinal cord dorsal horn (DH) and its influence on tactile representations in the brain are poorly understood. Using a range of mechanical stimuli applied to the skin, large-scale in vivo electrophysiological recordings, and genetic manipulations, here we show that neurons in the mouse spinal cord DH receive convergent inputs from both low- and high-threshold mechanoreceptor subtypes and exhibit one of six functionally distinct mechanical response profiles. Genetic disruption of DH feedforward or feedback inhibitory motifs, comprised of interneurons with distinct mechanical response profiles, revealed an extensively interconnected DH network that enables dynamic, flexible tuning of postsynaptic dorsal column (PSDC) output neurons and dictates how neurons in the primary somatosensory cortex respond to touch. Thus, mechanoreceptor subtype convergence and non-linear transformations at the earliest stage of the somatosensory hierarchy shape how touch of the skin is represented in the brain.


Assuntos
Mecanorreceptores , Corno Dorsal da Medula Espinal , Animais , Camundongos , Tato/fisiologia , Interneurônios , Encéfalo , Medula Espinal
2.
Mol Cell Proteomics ; 23(2): 100710, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38154690

RESUMO

Antibody glycosylation plays a crucial role in the humoral immune response by regulating effector functions and influencing the binding affinity to immune cell receptors. Previous studies have focused mainly on the immunoglobulin G (IgG) isotype owing to the analytical challenges associated with other isotypes. Thus, the development of a sensitive and accurate analytical platform is necessary to characterize antibody glycosylation across multiple isotypes. In this study, we have developed an analytical workflow using antibody-light-chain affinity beads to purify IgG, IgA, and IgM from 16 µL of human plasma. Dual enzymes, trypsin and Glu-C, were used during on-bead digestion to obtain enzymatic glycopeptides and protein-specific surrogate peptides. Ultra-high-performance liquid chromatography coupled with triple quadrupole mass spectrometry was used in order to determine the sensitivity and specificity. Our platform targets 95 glycopeptides across the IgG, IgA, and IgM isotypes, as well as eight surrogate peptides representing total IgG, four IgG classes, two IgA classes, and IgM. Four stable isotope-labeled internal standards were added after antibody purification to calibrate the preparation and instrumental bias during analysis. Calibration curves constructed using serially diluted plasma samples showed good curve fitting (R2 > 0.959). The intrabatch and interbatch precision for all the targets had relative standard deviation of less than 29.6%. This method was applied to 19 human plasma samples, and the glycosylation percentages were calculated, which were comparable to those reported in the literature. The developed method is sensitive and accurate for Ig glycosylation profiling. It can be used in clinical investigations, particularly for detailed humoral immune profiling.


Assuntos
Glicopeptídeos , Imunoglobulina G , Humanos , Glicosilação , Imunoglobulina G/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas , Glicopeptídeos/metabolismo , Digestão , Imunoglobulina A , Imunoglobulina M
3.
Clin Psychol Psychother ; 31(1): e2958, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38358078

RESUMO

OBJECTIVE: Borderline personality disorder (BPD) with auditory hallucinations (AHs) may inadvertently be misdiagnosed with a primary psychotic disorder, such as schizophrenia (SZ). This misidentification can lead to challenges in providing effective psychological treatment. This review therefore aims to identify the phenomenological characteristics of AHs in BPD in comparison to SZ, as well as psychological interventions that explicitly target AHs in BPD. METHODS: A systematic review was conducted to summarise the existing evidence base regarding the phenomenological similarities and differences of AHs in BPD and SZ, along with the identification of psychological interventions for AHs in BPD. RESULTS: Eighteen studies were eligible for inclusion. Compared to the SZ group, BPD clients were characterised by more persistent and repetitive AHs, significantly more voice-related distress and appraisals of omnipotence, and an earlier age of onset of AHs. The BPD group also reported more severe depression and anxiety, a higher incidence of childhood trauma, and more negative self-schema. Cognitive Behaviour Therapy Coping Strategy Enhancement (CBT-CSE) might be a promising intervention to reduce AH-related distress in BPD, although further studies are required to determine its effectiveness. CONCLUSION: In order to prevent misdiagnosis of AHs in BPD, the DSM-5 may need to acknowledge the broader and more frequent occurrence of psychosis symptoms in BPD clients. Such clarification may enhance diagnostic practices and facilitate more timely access to treatment. There is also a need to develop and trial psychological interventions that explicitly target AHs in BPD.


Assuntos
Transtorno da Personalidade Borderline , Terapia Cognitivo-Comportamental , Transtornos Psicóticos , Esquizofrenia , Humanos , Transtorno da Personalidade Borderline/complicações , Transtorno da Personalidade Borderline/diagnóstico , Transtorno da Personalidade Borderline/psicologia , Alucinações/complicações , Alucinações/diagnóstico , Esquizofrenia/complicações , Esquizofrenia/diagnóstico , Transtornos Psicóticos/psicologia
4.
Entropy (Basel) ; 25(7)2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37510032

RESUMO

Road segmentation is beneficial to build a vision-controllable mission-oriented self-driving bot, e.g., the Self-Driving Sweeping Bot, or SDSB, for working in restricted areas. Using road segmentation, the bot itself and physical facilities may be protected and the sweeping efficiency of the SDSB promoted. However, roads in the real world are generally exposed to intricate noise conditions as a result of changing weather and climate effects; these include sunshine spots, shadowing caused by trees or physical facilities, traffic obstacles and signs, and cracks or sealing signs resulting from long-term road usage, as well as different types of road materials, such as cement or asphalt; all of these factors greatly influence the effectiveness of road segmentation. In this work, we investigate the extension of Primordial U-Net by the proposed EnRDeA U-Net, which uses an input channel applying a Residual U-Net block as an encoder and an attention gate in the output channel as a decoder, to validate a dataset of intricate road noises. In addition, we carry out a detailed analysis of the nets' features and segmentation performance to validate the intricate noises dataset on three U-Net extensions, i.e., the Primordial U-Net, Residual U-Net, and EnRDeA U-Net. Finally, the nets' structures, parameters, training losses, performance indexes, etc., are presented and discussed in the experimental results.

5.
Surg Endosc ; 36(1): 346-351, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-33492509

RESUMO

INTRODUCTION: Our study aims to identify that patients who received hernia repair previously did have higher risk of occurrence of newly developed inguinal hernia, named as a contralateral inguinal hernia (CIH), than patients who never received inguinal hernia surgery before. MATERIALS AND METHODS: We collected data from the National Health Insurance Research Database (NHIRD) of Taiwan retrospectively. In the study cohort, 64,089 Asian male adults who underwent primary unilateral inguinal hernia repair during 2003-2008 were included using ICD-9 diagnostic and surgical codes. Another 64,089 male adults without hernia repair history were included as control group via propensity score match. RESULTS: The median follow-up period is 93.53 months. After multivariate analysis, the risk of newly developed inguinal hernia in unilateral inguinal hernia (UIH) repair cohort was significantly higher (adjusted HR 6.364, 95% CI 6.012-6.737, P < 0.001) than the control group. In subgroup analysis, patients without mesh repair (adjusted HR 6.706, P < 0.001) and patients with mesh repair (adjusted HR 5.559, P < 0.001) both showed higher risk of developing newly developed inguinal hernia which needs repair. CONCLUSIONS: Asian men with UIH repair history had a higher risk of developing new inguinal hernia at the contralateral site, namely CIH, than the general population. The surgeon should inform the possibility of CIH after initial herniorrhaphy, therefore, monitoring the occurrence of CIH is necessary.


Assuntos
Hérnia Inguinal , Adulto , Estudos de Coortes , Hérnia Inguinal/epidemiologia , Hérnia Inguinal/etiologia , Hérnia Inguinal/cirurgia , Herniorrafia/efeitos adversos , Humanos , Estudos Longitudinais , Masculino , Estudos Retrospectivos , Telas Cirúrgicas/efeitos adversos
6.
J Neurol Phys Ther ; 46(4): 270-280, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-35561104

RESUMO

BACKGROUND AND PURPOSE: A successful chair-rise is an important indicator of functional independence post-stroke. Lower extremity electromyographic analyses provide a basis for muscle activation from which clinical intervention protocols may be derived. Gluteus maximus activation during the chair-rise has not been thoroughly researched in the chronic stroke population. This study investigated the magnitude and onset of gluteus maximus activation during the chair-rise comparing adults post-stroke with healthy controls. METHODS: In this cross-sectional study, adults with chronic stroke (n = 12) and healthy controls (n = 12) completed 4 natural-speed chair-rise trials. Magnitude and onset of bilateral gluteus maximus activation were measured during the movement with secondary comparative data from biceps femoris and vastus lateralis muscles. Kinetic and kinematic measurements were used to quantify chair-rise phases and movement cycle duration. RESULTS: Significant decreases in paretic ( P = 0.002), and nonparetic ( P = 0.001) gluteus maximus magnitudes were noted post-stroke compared with ipsilateral extremities of healthy adults. Significant gluteus maximus onset delays were noted in paretic extremities compared with nonparetic extremities post-stroke ( P = 0.009) that were not apparent in comparative muscles. Similar onset times were noted when comparing the paretic extremity post-stroke to the ipsilateral extremity of healthy controls ( P = 0.714) despite prolonged movement cycle durations in those with chronic stroke ( P = 0.001). No onset delays were evident in the biceps femoris ( P = 0.72) or vastus lateralis ( P = 0.338) muscles. DISCUSSION AND CONCLUSIONS: Despite apparent unilateral muscle weakness post-stroke, bilateral decreases in gluteus maximus activation magnitudes and compounding onset deficits of the paretic extremity were observed during chair-rising. Further research is needed to determine whether interventions maximizing bilateral activation magnitudes and improving temporal activation congruency during chair-rising will carry over to functional gainsVideo Abstract available for more insights from the authors (see the Video, Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A387 ).


Assuntos
Músculo Esquelético , Acidente Vascular Cerebral , Adulto , Estudos Transversais , Eletromiografia/métodos , Humanos , Extremidade Inferior , Acidente Vascular Cerebral/complicações
7.
Int J Mol Sci ; 23(23)2022 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-36499166

RESUMO

Cilostazol is an antiplatelet agent with vasodilating effects that functions by increasing the intracellular concentration of cyclic adenosine monophosphate. We have previously shown that cilostazol has favorable effects on angiogenesis. However, there is no study to evaluate the effects of cilostazol on adiponectin. We investigated the effects of cilostazol on angiogenesis in diabetes in vitro and in vivo through adiponectin/adiponectin receptors (adipoRs) and the sirtuin 1 (SIRT1)/AMP-activated protein kinase (AMPK) signaling pathway. Human umbilical vein endothelial cells (HUVECs) and human aortic smooth muscle cells (HASMCs) were cocultured under high glucose (HG) conditions. Adiponectin concentrations in the supernatants were significantly increased when HASMCs were treated with cilostazol but not significantly changed when only HUVECs were treated with cilostazol. Cilostazol treatment enhanced the expression of SIRT1 and upregulated the phosphorylation of AMPK in HG-treated HUVECs. By sequential knockdown of adipoRs, SIRT1, and AMPK, our data demonstrated that cilostazol prevented apoptosis and stimulated proliferation, chemotactic motility, and capillary-like tube formation in HG-treated HUVECs through the adipoRs/SIRT1/AMPK signaling pathway. The phosphorylation of downstream signaling molecules, including acetyl-CoA carboxylase (ACC) and endothelial nitric oxide synthase (eNOS), was downregulated when HUVECs were treated with a SIRT1 inhibitor. In streptozotocin-induced diabetic mice, cilostazol treatment could improve blood flow recovery 21-28 days after inducing hindlimb ischemia as well as increase the circulating of CD34+CD45dim cells 14-21 days after operation; moreover, these effects were significantly attenuated by the knockdown of adipoR1 but not adipoR2. The expression of SIRT1 and phosphorylation of AMPK/ACC and Akt/eNOS in ischemic muscles were significantly attenuated by the gene knockdown of adipoRs. Cilostazol improves HG-induced endothelial dysfunction in vascular endothelial cells and enhances angiogenesis in diabetic mice by upregulating the expression of adiponectin/adipoRs and its SIRT1/AMPK downstream signaling pathway.


Assuntos
Diabetes Mellitus Experimental , Sirtuína 1 , Animais , Humanos , Camundongos , Acetil-CoA Carboxilase/metabolismo , Adiponectina/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Cilostazol/farmacologia , Diabetes Mellitus Experimental/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Isquemia/metabolismo , Fosforilação , Receptores de Adiponectina/genética , Receptores de Adiponectina/metabolismo , Transdução de Sinais , Sirtuína 1/genética , Sirtuína 1/metabolismo , Neovascularização Patológica
8.
Int J Mol Sci ; 23(17)2022 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-36077166

RESUMO

Proprotein convertase subtilisin/kexin type 9 (PCSK9) plays a key role in cholesterol homeostasis. Cilostazol exerts favorable cellular and metabolic effects; however, the effect of cilostazol on the expression of PCSK9 has not been previously reported. Our study aimed to investigate the potential mechanisms of action of cilostazol on the expression of PCSK9 and lipid homeostasis. We evaluated the effects of cilostazol on the expression of PCSK9 in HepG2 cells and evaluated potential molecular mechanisms by measuring signaling molecules in the liver and serum lipid profiles in high-fat diet-induced obese mice and normal chow-fed mice. Cilostazol treatment significantly induced the messenger RNA and protein expression of PCSK9 in HepG2 cells and enhanced PCSK9 promoter activity. Chromatin immunoprecipitation assays confirmed that cilostazol treatment enhanced PCSK9 transcription by binding to peroxisome proliferator-activated receptor-γ (PPARγ) via the PPARγ DNA response element. PPARγ knockdown attenuated the stimulatory effect of cilostazol on PCSK9. In vitro, cilostazol treatment increased PCSK9 expression in vehicle-treated HepG2 cells but decreased PCSK9 expression in palmitic acid-treated HepG2 cells. In vivo, cilostazol treatment increased the serum levels of PCSK9 in normal mice but significantly reduced PCSK9 levels in obese mice. The expressions of PCSK9-relevant microRNAs also showed similar results. Clinical data showed that cilostazol treatment significantly reduced serum PCSK9 levels in patients with obesity. The obesity-dependent effects of cilostazol on PCSK9 expression observed from bench to bedside demonstrates the therapeutic potential of cilostazol in clinical settings.


Assuntos
Pró-Proteína Convertase 9 , Pró-Proteína Convertases , Animais , Cilostazol/farmacologia , Lipídeos , Camundongos , Camundongos Obesos , Obesidade/tratamento farmacológico , PPAR gama/genética , PPAR gama/metabolismo , Pró-Proteína Convertase 9/genética , Pró-Proteína Convertase 9/metabolismo , Pró-Proteína Convertases/genética , Receptores de LDL/genética , Serina Endopeptidases/metabolismo , Subtilisinas
9.
Int J Mol Sci ; 22(9)2021 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33922657

RESUMO

BRCA mutation, one of the most common types of mutations in breast and ovarian cancer, has been suggested to be synthetically lethal with depletion of RAD52. Pharmacologically inhibiting RAD52 specifically eradicates BRCA-deficient cancer cells. In this study, we demonstrated that curcumin, a plant polyphenol, sensitizes BRCA2-deficient cells to CPT-11 by impairing RAD52 recombinase in MCF7 cells. More specifically, in MCF7-siBRCA2 cells, curcumin reduced homologous recombination, resulting in tumor growth suppression. Furthermore, a BRCA2-deficient cell line, Capan1, became resistant to CPT-11 when BRCA2 was reintroduced. In vivo, xenograft model studies showed that curcumin combined with CPT-11 reduced the growth of BRCA2-knockout MCF7 tumors but not MCF7 tumors. In conclusion, our data indicate that curcumin, which has RAD52 inhibitor activity, is a promising candidate for sensitizing BRCA2-deficient cells to DNA damage-based cancer therapies.


Assuntos
Proteína BRCA2/deficiência , Neoplasias da Mama/tratamento farmacológico , Curcumina/farmacologia , Dano ao DNA , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Recombinação Homóloga , Proteína Rad52 de Recombinação e Reparo de DNA/antagonistas & inibidores , Animais , Antineoplásicos/farmacologia , Apoptose , Proteína BRCA2/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Proliferação de Células , Reparo do DNA , Feminino , Humanos , Irinotecano/farmacologia , Camundongos , Camundongos Nus , Mutação , Inibidores da Topoisomerase I/farmacologia , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Arch Phys Med Rehabil ; 101(4): 599-606, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31821798

RESUMO

OBJECTIVE: To investigate the feasibility of conducting exoskeleton-assisted gait training (EGT) and the effects of EGT on gait, metabolic expenditure, and physical function in persons with multiple sclerosis (MS). DESIGN: Single-group pilot study. SETTING: Research laboratory in a rehabilitation hospital. PARTICIPANTS: Individuals with MS (N=10; mean age, 54.3±12.4y) and Expanded Disability Status Scale 6.0-7.5. INTERVENTIONS: All participants completed up to 15 sessions of EGT. MAIN OUTCOME MEASURES: Timed 25-foot walk test at self-selected and fast speed, 6-minute walk test, metabolic expenditure of walking and timed Up and Go test were assessed during walking without the exoskeleton at baseline and immediate post training. RESULTS: All participants tolerated the training intensity and completed training without adverse events. After training, gait speed was improved and metabolic expenditure was reduced significantly during the timed 25-foot walk test at self-selected speed. CONCLUSIONS: EGT is not only feasible but may also improve gait efficiency for persons with MS. Our observed improvement in gait speed was associated with reduced metabolic expenditure, which was likely because of improved neuromotor coordination. Further studies are required to investigate the effectiveness and integration of EGT in the continuum of MS rehabilitation.


Assuntos
Exoesqueleto Energizado , Transtornos Neurológicos da Marcha/reabilitação , Esclerose Múltipla/reabilitação , Adulto , Idoso , Teste de Esforço , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio , Projetos Piloto , Velocidade de Caminhada
11.
Appl Opt ; 59(3): 866-872, 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-32225219

RESUMO

In this paper, we experimentally demonstrate a strong correlation between the frequencies of the Raman pump and the Raman probe inside an optically pumped Raman laser. We show that the correlation is due to rapid adjustment of the phase of the dipoles that produce the Raman gain, following a sudden jump in the phase of the Raman pump. A detailed numerical model validates this interpretation of the phase correlation. The width of the spectrum of the beat between the Raman pump and the Raman laser is significantly narrowed due to this correlation. As a result, the minimum measurable change in the cavity length, for a given linewidth of the Raman pump laser, is substantially reduced. Therefore, this finding is expected to enhance the sensitivity of such a laser in various metrological applications (e.g., accelerometry).

12.
Hu Li Za Zhi ; 67(1): 66-80, 2020 Feb.
Artigo em Zh | MEDLINE | ID: mdl-31960398

RESUMO

BACKGROUND: Coronary artery disease is associated with unhealthy lifestyles such as smoking, lack of physical activity, and consuming an unhealthy diet. Other risk factors include family history and comorbidities such as hypertension, diabetes, smoking, obesity, and hypercholesterolemia. PURPOSE: This study aims to investigate the effectiveness of mobile health care in improving the physiological index of patients with coronary artery disease. METHODS: This study used an experimental design. Convenience sampling was used to enroll 129 patients with coronary heart disease as participants, who were randomly assigned into the intervention group (n = 64) and control group (n = 65). The intervention group participants received a 12-week mobile health care intervention, while the control group participants received routine care in the outpatient department. The physiological index outcome variables included body mass index (BMI), lipid profile, and blood pressure. Data were analyzed using generalized estimating equation curve analysis. RESULTS: The mean triglyceride (TG) reduction value after the intervention in the experimental group was significantly higher (reduction of 39.27 mg/dl; p < .05) than in the control group. Moreover, mean systolic blood pressure (SBP) and diastolic blood pressure (DBP) reduction values in the experimental group were significantly higher (reductions of 8.32 mmHg and 4.24 mmHg; p < .01) than in the control group. Furthermore, the mean reduction in BMI value in the experimental group was significantly higher (reduction of 0.48 Kg/m2; p < .05) than in the control group. Finally, only the mean reduction in low density lipoprotein (LDL) values was greater (by 1.11 mg/dl) in the experimental group than in the control group. However, this reduction did not reach statistical significance. CONCLUSIONS: Mobile health care has the potential to reduce TG, blood pressure, and BMI in patients with coronary artery disease.


Assuntos
Doença da Artéria Coronariana/fisiopatologia , Telemedicina , Pressão Sanguínea/fisiologia , Índice de Massa Corporal , Humanos , Resultado do Tratamento , Triglicerídeos/sangue
13.
Langmuir ; 35(15): 5221-5231, 2019 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-30883120

RESUMO

Carbon dioxide (CO2) is a renewable carbon source that is easily available in high purity and is utilized as a co-monomer in the direct ring-opening polymerization of epoxides to obtain aliphatic polycarbonates. In this work, degradable aliphatic polycarbonate diblock copolymers (mPEG- b-PBC) are synthesized via catalytic copolymerization of CO2 and 1,2-butylene oxide, starting from monomethoxy poly(ethylene glycol) (mPEG) as a chain transfer reagent. The polymerization proceeds at low temperatures and high CO2 pressure, utilizing the established binary catalytic system ( R, R)-Co(salen)Cl/[PPN]Cl. Amphiphilic nonionic diblock copolymers with varying PBC block lengths and hydrophilic-lipophilic balance values between 9 and 16 are synthesized. The polymers are characterized via NMR and Fourier transform infrared spectroscopies as well as size exclusion chromatography, exhibiting molecular weights ranging from 2400 to 4100 g mol-1 with narrow dispersities ( D = Mw/ Mn) from 1.07 to 1.18. Furthermore, the thermal properties, i.e., Tg, Tm, and Td, are determined. Surface tension measurements prove that the amphiphilic polymers form micelles above the critical micelle concentration, whereas small-angle neutron scattering shows that they are of nearly spherical shape. Adding small amounts of the synthesized mPEG- b-PBC polymers to different microemulsion systems, we found that the polymers were able to strongly increase the efficiency of medium-chain surfactants to solubilize polar oils.

14.
Chromosome Res ; 26(3): 153-162, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29159670

RESUMO

The maize B chromosome typically undergoes nondisjunction during the second microspore division. For normal A chromosomes, the r-X1 deficiency in maize can induce nondisjunction during the second megaspore and first microspore divisions. However, it is not known whether the r-X1 deficiency also induces nondisjunction of the maize B chromosome during these cell divisions. To answer this question, chromosome numbers were determined in the progeny of r-X1/R-r female parents carrying two B chromosomes. Some of the r-X1-lacking progeny (21.2%) contained zero or two B chromosomes. However, a much higher percentage of the r-X1-containing progeny (43.4%) exhibited zero or two B chromosomes, but none displayed more than two B chromosomes. Thus, the results indicated that the r-X1 deficiency could also induce nondisjunction of the B chromosome during the second megaspore division; moreover, the B chromosome in itself could undergo nondisjunction during the same division. In addition, pollen grains from plants with two B chromosomes lacking or exhibiting the r-X1 deficiency were compared via pollen fluorescence in situ hybridization (FISH) using a B chromosome-specific probe. The results revealed that the r-X1 deficiency could induce the occurrence of B chromosome nondisjunction during the first microspore division and that the B chromosome in itself could undergo nondisjunction during the same division at a lower frequency. Our data shed more light on the behavior of the maize B chromosome during cell division.


Assuntos
Divisão Celular/genética , Cromossomos de Plantas/genética , Zea mays/genética , Cromossomos de Plantas/metabolismo , Zea mays/metabolismo
15.
Opt Express ; 25(24): 30327-30335, 2017 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-29221062

RESUMO

We have demonstrated a laser in which the frequency shift due to small cavity fluctuations is far less than what would be expected from a conventional laser. The factor of sensitivity suppression is inferred to be equal to the effective group index experienced by the laser, implying that this laser is subluminal. We have observed a suppression factor as high as 663. Such a laser is highly self-stabilized compared to a conventional laser, and is expected to have a far smaller Schawlow-Townes linewidth. As a result, this laser may have potentially significant applications in the fields of high-precision optical metrology and passive frequency stabilization.

16.
Clin Exp Nephrol ; 21(2): 283-292, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27233502

RESUMO

BACKGROUND: Epidemiological studies show that 5-40 % of type 2 diabetes (T2DM) patients have diabetic nephropathy, and oxidative stress is one of several underlying mechanisms. We investigated associations between oxidative stress markers and severity of diabetic nephropathy. METHODS: Fifty-nine T2DM patients from the endocrinology outpatient department were included, and their levels of oxidative stress markers were measured. Three groups were determined by their urine albumin-to-creatinine ratio (UACR): group A (UACR < 30 mg/g, n = 22); group B (30 ≤ UACR < 300 mg/g, n = 22); and group C (UACR ≥ 300 mg/g, n = 15). RESULTS: Vitamin C levels correlated negatively and moderately with serum creatinine (γ = -0.459, p < 0.001), urine albumin (γ s = -0.458, p = 0.001) and UACR (γ s = -0.408, p = 0.001), but only weakly with hydroxy-2-deoxyguanosine (8-OHdG) and estimated glomerular filtration rate (eGFR). Vitamin C levels decreased as 8-OHdG, serum creatinine, albumin and UACR increased. T2DM patients with more severe diabetic nephropathy had lower vitamin C levels. CONCLUSION: Our results identified several oxidative stress markers that may be clinically important in diabetic nephropathy. Studies with larger sample sizes should be undertaken to confirm these findings.


Assuntos
Diabetes Mellitus Tipo 2/complicações , Nefropatias Diabéticas/etiologia , Estresse Oxidativo , 8-Hidroxi-2'-Desoxiguanosina , Idoso , Albuminúria/sangue , Albuminúria/etiologia , Albuminúria/urina , Antioxidantes/análise , Ácido Ascórbico/sangue , Biomarcadores/sangue , Biomarcadores/urina , Creatinina/sangue , Creatinina/urina , Desoxiguanosina/análogos & derivados , Desoxiguanosina/sangue , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/urina , Nefropatias Diabéticas/sangue , Nefropatias Diabéticas/diagnóstico , Nefropatias Diabéticas/urina , Feminino , Taxa de Filtração Glomerular , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Índice de Gravidade de Doença
17.
Appl Opt ; 56(10): 2754-2759, 2017 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-28375236

RESUMO

Optical target recognition using correlators is an important technique for fast verification and identification of images. The hybrid opto-electronic correlator (HOC) recently proposed by us bypasses the need for nonlinear materials such as photorefractive polymer films by using detectors instead, and the phase information is yet conserved by the interference of plane waves with the images. In this paper, we demonstrate experimentally the basic working principle of the HOC architecture using currently available technologies. For matched reference and query images, the output signal shows a sharp peak, indicating a match is found. For an unmatched case, a much lower peak value is observed, indicating no match. We also demonstrate the dependence of the output signal on the phases of the interfering plane waves and describe a technique using an interferometer and a servo for optimizing the output signal. As such, the work reported here paves the way for further development of the HOC for practical applications.

18.
Intern Med J ; 47(11): 1282-1291, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28742229

RESUMO

BACKGROUND/AIM: To examine the association between body composition and dialysis mortality. METHODS: Adult patients who underwent haemodialysis in Taoyuan General Hospital from 2012 to 2016 were enrolled. We reviewed their baseline characteristics and followed up their treatment over 5 years after dialysis. Patients with body mass index >25 kg/m2 were defined as obese. High or low muscle mass were classified by skeletal muscle mass index (SMMI) based on consensus from Chinese population. All age-matched subjects were classified into four groups: (A) optimal; (B) obesity; (C) low muscle mass; and (D) obesity with low muscle mass. Adjusted hazard ratios for mortality and cumulative survival curves were evaluated by Cox proportional hazard model and Kaplan-Meier method. The discriminative power of SMMI was calculated according to the area under the curve and the receiver operating characteristic curve. RESULTS: From a total of 176 age-matched patients, the incidence rates of mortality for different groups were 3.7, 7.8, 10.3 and 16.5 per 1000 person-months. After adjusting for continuous variables, SMMI was independently associated with mortality. The difference between groups A and D was more significant in women than in men after multivariate adjustment (adjusted hazard ratios: 7.465 vs 1.682) (P = 0.035 and 0.553). The discriminative power of SMMI to predict 5-year mortality was 0.700 for men and 0.750 for women, and the best cut-off values were 11.1 and 8.4 kg/m2 CONCLUSIONS: Low muscle mass was associated with dialysis mortality. Obesity with low muscle mass was a predictor for dialysis mortality in women.


Assuntos
Composição Corporal , Músculo Esquelético/patologia , Obesidade/mortalidade , Obesidade/terapia , Diálise Renal/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Composição Corporal/fisiologia , Estudos de Coortes , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Mortalidade/tendências , Obesidade/diagnóstico , Diálise Renal/tendências , Estudos Retrospectivos , Fatores de Risco
19.
Proteins ; 84(9): 1328-32, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27213893

RESUMO

The negatively charged bacterial polysaccharides-wall teichoic acids (WTAs) are synthesized intracellularly and exported by a two-component transporter, TagGH, comprising a transmembrane subunit TagG and an ATPase subunit TagH. We determined the crystal structure of the C-terminal domain of TagH (TagH-C) to investigate its function. The structure shows an N-terminal SH3-like subdomain wrapped by a C-terminal subdomain with an anti-parallel ß-sheet and an outer shell of α-helices. A stretch of positively charged surface across the subdomain interface is flanked by two negatively charged regions, suggesting a potential binding site for negatively charged polymers, such as WTAs or acidic peptide chains. Proteins 2016; 84:1328-1332. © 2016 Wiley Periodicals, Inc.


Assuntos
Transportadores de Cassetes de Ligação de ATP/química , Proteínas de Bactérias/química , Hidrolases/química , Subunidades Proteicas/química , Staphylococcus epidermidis/química , Ácidos Teicoicos/química , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Motivos de Aminoácidos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Sítios de Ligação , Transporte Biológico , Parede Celular/química , Clonagem Molecular , Cristalografia por Raios X , Escherichia coli/genética , Escherichia coli/metabolismo , Hidrolases/genética , Hidrolases/metabolismo , Modelos Moleculares , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Estrutura Secundária de Proteína , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Staphylococcus epidermidis/enzimologia , Eletricidade Estática , Ácidos Teicoicos/metabolismo
20.
J Vasc Surg ; 63(4): 1051-62.e3, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25595409

RESUMO

OBJECTIVE: Cilostazol is an antiplatelet agent with vasodilatory effects that works by increasing intracellular concentrations of cyclic adenosine monophosphate (cAMP). This study investigated the effects of cilostazol in preventing high glucose (HG)-induced impaired angiogenesis and examined the potential mechanisms involving activation of AMP-activated protein kinase (AMPK). METHODS: Assays for colony formation, adhesion, proliferation, migration, and vascular tube formation were used to determine the effect of cilostazol in HG-treated endothelial progenitor cells (EPCs) or human umbilical vein endothelial cells (HUVECs). Animal-based assays were performed in hyperglycemic ICR mice undergoing hind limb ischemia. An immnunoblotting assay was used to identify the expression and activation of signaling molecules in vitro and in vivo. RESULTS: Cilostazol treatment significantly restored endothelial function in EPCs and HUVECs through activation of AMPK/acetyl-coenzyme A carboxylase (ACC)-dependent pathways and cAMP/protein kinase A (PKA)-dependent pathways. Recovery of blood flow in the ischemic hind limb and the population of circulating CD34(+) cells were significantly improved in cilostazol-treated mice, and these effects were abolished by local AMPK knockdown. Cilostazol increased the phosphorylation of AMPK/ACC and Akt/endothelial nitric oxide synthase signaling molecules in parallel with or downstream of the cAMP/PKA-dependent signaling pathway in vitro and in vivo. CONCLUSIONS: Cilostazol prevents HG-induced endothelial dysfunction in EPCs and HUVECs and enhances angiogenesis in hyperglycemic mice by interactions with a broad signaling network, including activation of AMPK/ACC and probably cAMP/PKA pathways.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Indutores da Angiogênese/farmacologia , Diabetes Mellitus Experimental/enzimologia , Células Progenitoras Endoteliais/efeitos dos fármacos , Glucose/metabolismo , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Isquemia/tratamento farmacológico , Músculo Esquelético/irrigação sanguínea , Neovascularização Fisiológica/efeitos dos fármacos , Tetrazóis/farmacologia , Proteínas Quinases Ativadas por AMP/genética , Animais , Adesão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Cilostazol , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Experimental/fisiopatologia , Relação Dose-Resposta a Droga , Células Progenitoras Endoteliais/enzimologia , Células Progenitoras Endoteliais/patologia , Membro Posterior , Células Endoteliais da Veia Umbilical Humana/metabolismo , Células Endoteliais da Veia Umbilical Humana/patologia , Humanos , Isquemia/enzimologia , Isquemia/patologia , Isquemia/fisiopatologia , Masculino , Camundongos Endogâmicos ICR , Fosforilação , Interferência de RNA , Recuperação de Função Fisiológica , Fluxo Sanguíneo Regional , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo , Transfecção
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