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1.
Clin Case Rep ; 12(5): e8784, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38721554

RESUMO

Cytomegalovirus colitis should be considered in a patient presenting with bloody stool even among immunocompetent patients.

2.
IDCases ; 36: e01940, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38681080

RESUMO

Bacillus cereus (B. cereus) is commonly found in the environment and is often considered a blood culture contaminant. However, in patients with specific risk factors such as intravenous drug use, central venous access catheters, immunosuppression, or prosthetic valves, B. cereus can cause severe infections. Herein, we present a case of prosthetic valve endocarditis (PVE) caused by B. cereus in an 84-year-old woman with a history of aortic valve replacement for aortic stenosis five years earlier. She presented with anorexia, and her physical examination revealed tenderness in the left upper quadrant of the abdomen. Blood culture grew B. cereus, and a CT scan showed splenic infarction, raising suspicion of PVE. Transesophageal echocardiogram (TEE) revealed an abscess around the left coronary cusp of the aortic valve and a 15 mm vegetation. Due to the patient's high risk for post-operative complications and her unwillingness to undergo surgery, the surgery was deferred. Instead, she was successfully treated with six weeks of intravenous vancomycin and discharged home. Follow-up TEE demonstrated resolution of the vegetation and valvular abscess. At her six-month post-discharge evaluation, no signs of active infection were noted including fever or worsening heart failure. Although surgery is typically recommended for most cases of PVE, conservative treatment can be considered as an alternative option for selected patients.

3.
Vaccine ; 42(3): 464-470, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38172019

RESUMO

BACKGROUND: In Japan, freeze-dried live attenuated Oka-strain varicella-zoster virus vaccine, VVL (BIKEN), is available for adults aged ≥50 years to prevent herpes zoster (HZ). Although an increase in the antibody titer and cellular immune response has been demonstrated following vaccination with VVL (BIKEN), to date, no clinical studies have shown that the vaccine decreases the incidence of HZ and postherpetic neuralgia (PHN). This study investigated the incidence of HZ and PHN among adults aged ≥50 years who received a single dose of VVL (BIKEN) to prevent HZ. METHODS: This retrospective cohort study investigated the incidence of HZ and PHN among adults aged ≥50 years who received a single dose of VVL (BIKEN) at a large hospital and affiliated clinics in Japan. A dispensing database and electronic medical records were used to identify vaccine recipients and cases of HZ and PHN. The end date of the follow-up period and the reason to end the follow-up were defined to avoid underestimating the incidence. The analysis was stratified according to age, sex, immunocompromising conditions, and use of immunosuppressant therapy. Vaccine effectiveness was estimated using published estimates of the incidence of HZ and PHN in the unvaccinated population in Japan. RESULTS: A total of 1175 patients were enrolled in the study. During a median follow-up period of 3.36 years, HZ was diagnosed in 27 participants (15 men [2.8%] and 12 women [1.9%]). The incidence of HZ among VVL (BIKEN) recipients was 7.67/1000 person-years. The incidence of PHN was 0.82/1000 person-years. The vaccine effectiveness was estimated as 27.8% [95% confidence interval (CI), -29.8 to 63.9%] and 73.8% [95% CI, 38.6-100%] against HZ and PHN, respectively. CONCLUSIONS: The VVL (BIKEN) had limited effectiveness at preventing HZ, but relatively good effectiveness at preventing PHN. VVL (BIKEN) might have a role as an affordable alternative.


Assuntos
Vacina contra Herpes Zoster , Herpes Zoster , Neuralgia Pós-Herpética , Masculino , Adulto , Humanos , Feminino , Neuralgia Pós-Herpética/epidemiologia , Neuralgia Pós-Herpética/prevenção & controle , Herpesvirus Humano 3 , Incidência , Japão/epidemiologia , Estudos Retrospectivos , Herpes Zoster/epidemiologia , Herpes Zoster/prevenção & controle , Vacina contra Varicela
4.
Clin Case Rep ; 11(12): e8308, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38107080

RESUMO

Paget-Schroetter syndrome is the primary thrombotic event associated with venous thoracic outlet syndrome. It needs to be suspected when encountering localized brachial swelling and a dilated vein in patients with a history of upper limb exercise.

5.
IDCases ; 32: e01775, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37324237

RESUMO

•We experienced a case of necrotizing fasciitis (NF) due to Group A streptococcus in a healthy Japanese man.•Cutaneous manifestations with NF can be initially minimal.•It is important to recognize that one of the characteristic symptoms of NF is severe pain out of proportion.•When NF is suspect, emergent surgical exploration and debridement are required.

6.
Nagoya J Med Sci ; 84(4): 689-704, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36544605

RESUMO

This systematic review aimed to confirm the effectiveness of hand therapy programmes using the International Classification of Functioning, Disability and Health framework for each of the three phases of the wound healing process in adults with burns. A systematic review was conducted to determine the efficacy of different hand therapy programmes in the management of burnt hands. Two independent reviewers conducted a literature search using the PubMed and Cumulative Index to Nursing and Allied Health Literature databases for original articles reporting effectiveness of hand therapy programmes for adults with burns. Only randomized and non-randomized controlled trials were selected using the Mixed Methods Appraisal Tool. Demographic and clinical data including medical history, burn depth, and hand therapy programme were extracted. Outcome measures were reviewed based on the International Classification of Functioning, Disability and Health framework for acute, convalescence, and chronic phases of rehabilitation. Sixteen articles and 15 hand therapy programmes were identified, which included studies showing improvements in different parameters in the framework. In the acute and convalescence phases, improvements were found in health condition, body functions and structures, activities, and participation. In the chronic phase, improvements were shown only in body functions and structures. Environmental factors in the framework were not reported for all the phases. This review demonstrated the efficacy of hand therapy programmes in adults with burns in terms of the health condition, body function, activities, and participation during acute and convalescence phases but only the body function in the chronic phase.


Assuntos
Queimaduras , Classificação Internacional de Funcionalidade, Incapacidade e Saúde , Humanos , Adulto , Convalescença , Avaliação de Resultados em Cuidados de Saúde/métodos , Queimaduras/reabilitação
7.
IBRO Neurosci Rep ; 10: 208-215, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34095892

RESUMO

Quantitative objective measurement of chronic pain is important. We elucidated chronic pain-related cortical neural activity and neural connectivity among pain-related brain regions in complex regional pain syndrome (CRPS). Resting-state magnetoencephalography recordings were performed. Cortical current density and neural connectivity, revealed by amplitude envelope correlation (AEC), were estimated on standardized brain magnetic resonance imaging. Intra-experiment pain was assessed subjectively using a visual analogue scale (VAS). The correlation between current density and VAS scores was calculated for the occipital areas and pain-related cortices. Current density in the primary (SI) and secondary (SII) somatosensory cortex and precuneus in both hemispheres was negatively correlated with the pain VAS score. The AEC and VAS values were significantly correlated for the SII and the precuneus and for the SII and insular cortex in the alpha frequency band in the right hemisphere. In the theta frequency band, the AEC and VAS values correlated for the SII and posterior cingulate cortex in the right hemisphere. Our results suggested that disruption of pain processes and functions in the default mode network occurs in CRPS. Our method targeting the neural mechanism of pain has the potential to offer a clinically objective means of evaluating it.

8.
NeuroRehabilitation ; 46(3): 423-431, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32250335

RESUMO

BACKGROUND: Several studies on carpal tunnel syndrome have reported pain that exists beyond the median nerve territory of the affected hand. However, the mechanism is unknown. PURPOSE: We investigated the cause of extra-territorial pain by the analysis of clinical assessments and cortical activity using magnetoencephalography. METHODS: To compare patients with and without extra-territorial pain, fourteen patients with carpal tunnel syndrome were assessed using clinical examination, such as patients' profile, paresthesia, physical tests, and psychological tests. The physical assessment included tactile threshold and static and moving two-point discrimination sensations on digital pulp. Neural activation in the cerebral cortex was also measured using z-scores calculated by magnetoencephalography. RESULTS: Among fourteen patients, ten patients had pain in the affected median nerve territory only and four patients had extra-territorial pain. When comparing the groups, the static and moving two-point discrimination sensation values in patients with extra-territorial pain were larger than those of patients without the pain (p < 0.05). The supra-marginal gyrus, mid-part of the precentral sulcus, angular gyrus in the left hemisphere, bilateral sensorimotor areas for legs, and bilateral isthmus-cingulate areas showed larger z-scores in patients with extra-territorial pain than in patients without the pain (p < 0.05). CONCLUSIONS: The static and moving two-point discrimination sensations signify the ability of tactile spatial acuity. Bilateral sensorimotor areas were activated in sites that were not the hand. Furthermore, the inferior parietal lobule in the left hemisphere, which synthesizes and integrates multiple sensations showed high activation. Our findings suggested that the mechanism of extra-territorial pain was associated with dysfunction of spatial cognition.


Assuntos
Síndrome do Túnel Carpal/fisiopatologia , Dor Referida/fisiopatologia , Idoso , Feminino , Dedos/fisiopatologia , Humanos , Magnetoencefalografia , Masculino , Nervo Mediano/fisiopatologia , Pessoa de Meia-Idade , Transtornos da Percepção/fisiopatologia
9.
J Neurooncol ; 146(1): 195-205, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31853839

RESUMO

PURPOSE: This study aimed to investigate the preoperative predictive factors affecting return to work in patients with gliomas in the left cerebral hemisphere undergoing awake surgery. METHODS: We retrospectively reviewed 50 consecutive glioma patients who underwent awake surgery from January 2012 to July 2017. Adult patients older than 18 years, who reported working prior to surgery, were recruited for this study. RESULTS: Comparing sociodemographic, disease-related and preoperative neurocognitive variables of glioma patients who returned to work and those who did not, binomial logistic regression models for preoperative predictors affecting return to work revealed significant differences in age and sole breadwinner status as sociodemographic variables, tumour volume as a disease-related variable, and Verbal IQ, Performance IQ, general memory, attention/concentration, and working memory as neurocognitive variables. Multivariate logistic regression models demonstrated that the independent factors associated with propriety of returning to work 1 year after surgery was the sociodemographic variable sole breadwinner status (yes vs no; OR = 15.00, 95% CI 2.22-101.35, p = 0.01), the disease-related variable tumour volume (per 1 cm3; OR = 0.98, 95% CI 0.96-0.99, p = 0.04), and the preoperative neurocognitive variable general memory (≥ 100 vs < 100; OR = 21.70, 95% CI 2.60-183.94, p = 0.01). CONCLUSIONS: Our results suggest that three predictive factors including sole breadwinner status, tumour volume and general memory that can be assessed in the preoperative stage substantially contribute to returning to work in patients with gliomas in the left cerebral hemisphere, 1 year after awake surgery.


Assuntos
Mapeamento Encefálico/métodos , Neoplasias Encefálicas/cirurgia , Craniotomia/métodos , Glioma/cirurgia , Cuidados Pré-Operatórios , Indicadores de Qualidade em Assistência à Saúde , Retorno ao Trabalho/estatística & dados numéricos , Adulto , Idoso , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/psicologia , Cognição , Feminino , Seguimentos , Glioma/patologia , Glioma/psicologia , Humanos , Renda , Masculino , Memória , Pessoa de Meia-Idade , Monitorização Intraoperatória , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Mudança Social , Carga Tumoral , Vigília , Adulto Jovem
10.
Sci Rep ; 9(1): 19776, 2019 12 24.
Artigo em Inglês | MEDLINE | ID: mdl-31874978

RESUMO

We investigate changes in brain function before and after carpal tunnel release. Magnetoencephalography (MEG), during which we recorded somatosensory evoked cortical magnetic fields (SEFs), and a clinical evaluation were performed before surgery and 6 months after. The distance on the vertical axis between the equivalent current dipoles (ECDs) for the first and third digits before surgery was significantly less than after surgery. There were no significant differences in values between the control participant and patients after surgery. In terms of distal motor latency, there was a negative correlation with the distance. The recovery function of the root mean square (RMS) before surgery for the N20m was less suppressed at 10 ms of ISI in patients, compared to controls. There were no significant differences in the RMS values for patients before and after surgery. Our results indicate that treating peripheral nerve lesions, such as in carpal tunnel release, positively modifies brain function.


Assuntos
Síndrome do Túnel Carpal/fisiopatologia , Potenciais Somatossensoriais Evocados , Magnetoencefalografia , Córtex Somatossensorial/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
11.
NeuroRehabilitation ; 44(2): 199-205, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30856127

RESUMO

BACKGROUND: The upper extremity disability in patients with carpal tunnel syndrome (CTS) is related to dysfunction due to the median nerve damage. However, there is no report on which dysfunctions affect the upper extremity disability. PURPOSE: This study aimed to investigate which clinical factors influence upper extremity disability in women with CTS. METHODS: We analyzed 60 hands of women with bilateral idiopathic CTS. Upper extremity disability was assessed using Hand10, a validated and self-administered tool. Pain intensity was measured using the Japanese version of the Short-Form McGill Pain Questionnaire (SF-MPQ-J). We performed nerve conduction studies, assessed physical and psychological parameters, and collected demographic data. Physical parameters comprised grip strength, pinch strength, tactile threshold, static 2-point discrimination sensation, and severity of numbness. Psychological parameters include depression, pain anxiety, and distress. RESULTS: The bivariate analysis revealed that Hand10 was significantly correlated with age, symptom duration, SF-MPQ-J, grip strength, pain anxiety, and distress. Multiple regression analysis demonstrated that SF-MPQ-J and grip strength were related to Hand10 score. CONCLUSIONS: Pain intensity and grip strength were dysfunctions affecting the upper extremity disability in women with bilateral idiopathic CTS. Rehabilitation approaches for CTS should be considered based on the adaptive activities of the neural networks.


Assuntos
Síndrome do Túnel Carpal/fisiopatologia , Força da Mão , Dor/fisiopatologia , Adulto , Idoso , Síndrome do Túnel Carpal/complicações , Sensibilização do Sistema Nervoso Central , Feminino , Humanos , Pessoa de Meia-Idade , Dor/epidemiologia , Dor/etiologia
12.
Org Lett ; 20(18): 5826-5830, 2018 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-30179009

RESUMO

A synthetic route to chiral selenazolines from readily available N-acyloxazolidinones via a selenative rearrangement of a chiral cyclic skeleton is reported. The reaction proceeds in the presence of elemental selenium, a hydrochlorosilane, and an amine. Although the stability of the obtained selenazoline products is relatively low, a wide range of selenazolines was successfully prepared.

13.
Adv Mater ; 29(22)2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28370452

RESUMO

Red-emitting piezoluminescence (elasticoluminescence) is achieved by doping rare earth Pr3+ into the well-known piezoelectric matrix, LiNbO3 . By precisely tuning the Li/Nb ratio in nonstoichiometric Li x NbO3 :Pr3+ , a material that exhibits an unusually high piezoluminescence intensity, which far exceeds that of any well-known piezoelectric material, is produced. Li x NbO3 :Pr3+ shows excellent strain sensitivity at the lowest strain level, with no threshold for stress sensing. These multipiezo properties of sensitive piezoluminescence in a piezoelectric matrix are ideal for microstress sensing, damage diagnosis, electro-mechano-optical energy conversion, and multifunctional control in optoelectronics.

14.
Sci Rep ; 6: 36880, 2016 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-27841288

RESUMO

Although solution-plasma processing enables room-temperature synthesis of nanocarbons, the underlying mechanisms are not well understood. We investigated the routes of solution-plasma-induced nanocarbon formation from hexane, hexadecane, cyclohexane, and benzene. The synthesis rate from benzene was the highest. However, the nanocarbons from linear molecules were more crystalline than those from ring molecules. Linear molecules decomposed into shorter olefins, whereas ring molecules were reconstructed in the plasma. In the saturated ring molecules, C-H dissociation proceeded, followed by conversion into unsaturated ring molecules. However, unsaturated ring molecules were directly polymerized through cation radicals, such as benzene radical cation, and were converted into two- and three-ring molecules at the plasma-solution interface. The nanocarbons from linear molecules were synthesized in plasma from small molecules such as C2 under heat; the obtained products were the same as those obtained via pyrolysis synthesis. Conversely, the nanocarbons obtained from ring molecules were directly synthesized through an intermediate, such as benzene radical cation, at the interface between plasma and solution, resulting in the same products as those obtained via polymerization. These two different reaction fields provide a reasonable explanation for the fastest synthesis rate observed in the case of benzene.

15.
Clin Neurophysiol ; 127(8): 2733-2738, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27417045

RESUMO

OBJECTIVE: The recovery function of somatosensory evoked magnetic fields (SEFs) was recorded to investigate excitatory and inhibitory balance in the somatosensory cortex of patients with carpal tunnel syndrome. METHODS: SEFs were recorded in patients and controls. Recordings were taken following median nerve stimulation with single and double pulses with interstimulus intervals of 10-200ms. The root mean square for the N20m component following the second stimulation was analyzed. SEFs following stimulation of the first and middle digits were also recorded and the location for the equivalent current dipoles was estimated in three-dimensional planes. RESULTS: Distances on the vertical axis between the equivalent current dipoles for the first and third digits were shorter in patients than in control participants. The root mean square for the N20m recovered earlier in patients compared to controls; this was statistically significant at an interstimulus interval of 10ms. There was no relationship between N20m recovery and the equivalent current dipole location in the primary somatosensory cortex. CONCLUSIONS: Carpal tunnel syndrome was associated with functional disinhibition and destruction of the somatotopic organization in the primary somatosensory cortex. SIGNIFICANCE: Disinhibitory changes might induce a maladaptation of the central nervous system relating to pain.


Assuntos
Síndrome do Túnel Carpal/fisiopatologia , Potenciais Somatossensoriais Evocados/fisiologia , Nervo Mediano/fisiopatologia , Córtex Somatossensorial/fisiopatologia , Idoso , Mapeamento Encefálico , Estimulação Elétrica , Feminino , Humanos , Magnetoencefalografia , Masculino , Pessoa de Meia-Idade , Tempo de Reação/fisiologia
16.
Springerplus ; 3: 284, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24944880

RESUMO

Grating-coupled propagating surface plasmons associated with silver-nanoparticle 2D crystalline sheets exhibit sensitive plasmonic resonance tuning. Multilayered silver-nanoparticle 2D crystalline sheets are fabricated on gold or silver grating surfaces by the Langmuir- Blodgett method. We show that the deposition of Ag crystalline nanosheets on Au or Ag grating surfaces causes a drastic change in propagating surface plasmon resonance (SPR) both in angle measurements at fixed wavelengths and in fixed incident-angle mode by irradiation of white light. The dielectric constant of the multilayered silver nanosheet is estimated by a rigorous coupled-wave analysis. We find that the dielectric constant drastically increases as the number of silver-nanosheet layers increases. The experimentally obtained SP dispersions of Ag crystalline nanosheets on Au and Ag gratings are compared with the calculated SP dispersion curves. The drastic change in the surface plasmon resonance caused by the deposition of Ag-nanoparticle 2D crystalline sheets on metal grating surfaces suggests the potential for applications in highly sensitive sensors or for plasmonic devices requiring greatly enhanced electric fields.

17.
Langmuir ; 28(49): 17153-8, 2012 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-23153010

RESUMO

We report the fabrication technique and optical properties of multilayered two-dimensional (2D) gold nanoparticle sheets ("Au nanosheet"). The 2D crystalline monolayer sheet composed of Au nanoparticles shows an absorption peak originating from a localized surface plasmon resonance (LSPR). It was found that the absorption spectra dramatically change when the monolayers are assembled into the multilayers on different substrates (quartz or Au). In the case of the multilayers on Au thin film (d = 200 nm), the LSPR peak is shifted to longer wavelength at the near-IR region by increasing the number of layers. The absorbance also depends on the layer number and shows the nonlinear behavior. On the other hand, the multilayers on quartz substrate show neither such LSPR peak shift nor nonlinear response of absorbance. The layer number dependence on metal surfaces can be interpreted as the combined effects between the near-field coupling of the LSPR and the far-field optics of the stratified metamaterial films, as proposed in our previous study. We also report the spectroscopic properties of hybrid multilayers composed of two kinds of monolayers, i.e., Au nanosheet and Ag nanosheet. The combination of the different metal nanoparticle sheets realizes more flexible plasmonic color tuning.

18.
Phys Chem Chem Phys ; 13(39): 17625-32, 2011 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-21897958

RESUMO

Interactions of gelatin and albumin with a photo-reactive diphenylamino-s-triazine bridged p-phenylene vinylene polymer (DTOPV) were examined by using surface plasmon resonance (SPR) spectroscopy to explore the effect of the polymer structure on protein coverage of DTOPV nanofilms. The SPR data revealed a significant increase of gelatin adsorption on UV-DTOPV nanofilms, while the adsorption of albumin was decreased by UV exposure in the time frame of the experiment. We also found that the selective adsorption of these proteins was highly dependent on the protein concentration; the highest selectivity of protein adsorption was obtained at the lowest concentration (3.5 µg ml(-1)), while no selective adsorption was confirmed at high concentrations (350 and 1000 µg ml(-1)). The selective attachment of mesenchymal stem cells (MSCs) was directly correlated with the selective adsorption of these proteins onto DTOPV nanofilms. The MSCs attachment onto UV-DTOPV films was promoted with only small mass coverage of gelatin, which led to MSC patterning onto the patterned DTOPV nanofilms successfully. The role of cell adhesion proteins that we found in this study will be a clue to elucidate the complex response of biomolecules on functional polymer nanolayers, and contribute to build up biocompatible surfaces on various advanced materials for the sake of cell engineering and medical implants.


Assuntos
Albuminas/química , Gelatina/química , Células-Tronco Mesenquimais/química , Polivinil/química , Adsorção , Humanos , Ressonância de Plasmônio de Superfície , Propriedades de Superfície
19.
Langmuir ; 25(19): 11802-7, 2009 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-19655781

RESUMO

The composite gold nanorods (Au NRs) having a double-shell structure composed of Au NR (core), spacer layer (inner shell), and J-aggregate (JA) layer (outer shell) have been synthesized to examine the spectroscopic properties of the hybrid system in which the localized surface plasmon is coupled with the molecular exciton of JA. The spacer layer consisting of N,N,N-trimethyl(11-mercaptoundecyl)ammonium chloride plays a significant role in the formation of JA shell for several kinds of cyanine dyes. The absorption spectra of composite NRs are characterized by a distinct dip near the J-band when the plasmon energy of Au core is close to the exciton energy of JA shell, whereas a normal J-band peak appears when two energies are widely different from each other. The gradual change from the dip type to peak type absorption was observed when the plasmon energy was modulated by varying the aspect ratio of Au NR. Furthermore, composite NRs with thicker spacer layers have been fabricated by inserting the multilayer shell of polyelectrolytes between TMA and JA layers. They exhibited an alteration of the spectral line shape from the dip type to peak type with increase in the thickness of spacer layer. These observations have been interpreted in terms of the strength of the exciton-plasmon coupling, which is sensitive to the configuration of composite NRs as well as the relative difference between plasmon and exciton energies.

20.
Langmuir ; 25(12): 6683-9, 2009 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-19371042

RESUMO

Composite nanoparticles (NPs) having a double-shell structure, Au core, spacer layer (inner shell), and J-aggregate (JA) layer (outer shell) (Au/spacer/JA) have been synthesized. The spacer layer composed of N,N,N-trimethyl(11-mercaptoundecyl)ammonium chloride played an important role in promoting the J-aggregation of anionic cyanine dyes on the surface, as evidenced by the successful formation of the JA layers with four kinds of anionic cyanine dyes. It was found that the presence of a spacer layer causes a significant change in the line shape of the absorption spectrum, particularly near the J-band; there is the appearance of a peak type absorption for the composite NPs with the double-shell structure, while there is a dip type absorption for the ones without the spacer layer. The change from the peak type absorption to the dip type absorption in the Au/spacer/JA NPs occurs when the size of the Au core is varied from 5 to 15 nm. These observations would indicate that the strength of exciton-plasmon coupling between the Au core and the JA layer is enhanced with the increase in the core size or the decrease in the separation between the Au core and the JA shell. The photoluminescence arising from the JA can be detected for the composite NPs with the double-shell structure, showing that the quenching by the Au core is effectively suppressed by the spacer layer.

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