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1.
J Chem Phys ; 160(20)2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38785281

RESUMO

Colloidal quantum dots are of increasing interest for mid-infrared detection and emission, but device performances will vastly benefit from reducing the non-radiative recombination. Empirically, the photoluminescence quantum yield decreases exponentially toward the mid-infrared, which appears similar to the energy gap law known for molecular fluorescence in the near-infrared. For molecules, the mechanism is electron-vibration coupling and fast internal vibrational relaxation. Here, we explore the possible mechanisms for inorganic quantum dots. The primary mechanism is assigned to an electric dipole near-field energy transfer from the quantum dot electronic transitions to the infrared absorption of surface organic ligands and then to the multiphonon absorption of the quantum dot inorganic core or the surrounding inorganic matrix. In order to obtain luminescent quantum dots in the 3-10 µm range, we motivate the importance of using inorganic matrices, which have a higher infrared transparency compared to organic materials. At longer wavelengths, inter-quantum dot energy transfer is noted to be much faster than radiative relaxation, indicating that bright mid-infrared colloidal quantum dot films might then benefit from dilution.

2.
J Am Chem Soc ; 145(19): 10809-10816, 2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37134313

RESUMO

Fluorophores emitting in the NIR-IIb wavelength range (1.5-1.7 µm) show great potential for bioimaging due to their large tissue penetration. However, current fluorophores suffer from poor emission with quantum yields ∼2% in aqueous solvents. In this work, we report the synthesis of HgSe/CdSe core/shell quantum dots (QDs) emitting at 1.7 µm through the interband transition. Growth of a thick shell led to a drastic increase in the photoluminescence quantum yield, with a value of 63% in nonpolar solvents. The quantum yields of our QDs and other reported QDs are explained well by a model of Forster resonance energy transfer to ligands and solvent molecules. The model predicts a quantum yield >12% when these HgSe/CdSe QDs are solubilized in water. Our work demonstrates the importance of a thick type-I shell to obtain bright emission in the NIR-IIb region.

3.
J Am Chem Soc ; 143(46): 19567-19575, 2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34752062

RESUMO

A procedure is developed for the growth of thick, conformal CdS shells that preserve the optical properties of 5 nm HgSe cores. The n-doping of the HgSe/CdS core/shell particles is quantitatively tuned through a simple postsynthetic Cd treatment, while the doping is monitored via the intraband optical absorption at 5 µm wavelength. Photoluminescence lifetime and quantum yield measurements show that the CdS shell greatly increases the intraband emission intensity. This indicates that decoupling the excitation from the environment reduces the nonradiative recombination. We find that weakly n-type HgSe/CdS are the brightest solution-phase mid-infrared chromophores reported to date at room temperature, achieving intraband photoluminescence quantum yields of 2%. Such photoluminescence corresponds to intraband lifetimes in excess of 10 ns, raising important questions about the fundamental limits to achievable slow intraband relaxation in quantum dots.

4.
J Contemp Dent Pract ; 15(1): 20-5, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-24939259

RESUMO

INTRODUCTION: Liquid oral medicines being the most accepted form of medication in children are frequently prescribed. The harmful effects of these liquid medicaments on a child's dental health are not known to many. The present study aimed to evaluate and compare the cariogenic and erosive potential of 5 most commonly prescribed pediatric liquid medicaments (PLM) in Pimpri Chinchwad and Pune city, Pune district. MATERIALS AND METHODS: Most commonly prescribed PLM in Pune district were selected as opined by 50 pediatricians. The selected medicaments were Syr. Augmentin® Duo, Syr. Valparin®, Syr. Combiflam®, Syr. Visyneral and Syr. Orofer®. An estimation of pH, percentage of sucrose concentration and calcium dissolving capacity of these preparations was carried out. The results as obtained were subjected to statistical analysis using SPSS v 17.0 for windows. The statistical test as undertaken was Pearson's correlation coeffcient(r). RESULTS: Sucrose was seen to be present in Syr. Combiflam® (35.75% ± 0.25%) and Syr. Visyneral (18.48% ± 0.43%). Acidic pH was observed for Syr. Visyneral (mean pH 3.63 ± 0.04), Syr. Combiflam®(mean pH 5.03 ± 0.02) and Syr. Augmentin® (mean pH 6.22 ± 0.02). Highest calcium dissolution was seen with Syr. Combiflam®(295.86 mg/ml) and the least with Syr. Orofer® (25.51 mg/ml). No statistical significant correlation was observed with calcium dissolution potential of PLM in comparison with their respective pH. CONCLUSION: Syr. Combiflam® can be regarded as the highest cariogenic and erosive potential medicament among the compared and tested PLM. CLINICAL SIGNIFICANCE: Considering syrups with high cariogenic and erosive potential should always follow with proper oral hygiene practices or search for an alternative drugs void of such detrimental effects.


Assuntos
Cariogênicos/efeitos adversos , Soluções Farmacêuticas/efeitos adversos , Edulcorantes/efeitos adversos , Erosão Dentária/induzido quimicamente , Acetaminofen/efeitos adversos , Acetaminofen/análise , Combinação Amoxicilina e Clavulanato de Potássio/efeitos adversos , Combinação Amoxicilina e Clavulanato de Potássio/análise , Antibacterianos/efeitos adversos , Antibacterianos/análise , Anti-Inflamatórios não Esteroides/efeitos adversos , Anti-Inflamatórios não Esteroides/análise , Anticonvulsivantes/efeitos adversos , Anticonvulsivantes/análise , Antipiréticos/efeitos adversos , Antipiréticos/análise , Cálcio/química , Esmalte Dentário/química , Esmalte Dentário/efeitos dos fármacos , Suplementos Nutricionais/efeitos adversos , Suplementos Nutricionais/análise , Combinação de Medicamentos , Compostos Férricos/efeitos adversos , Compostos Férricos/análise , Humanos , Concentração de Íons de Hidrogênio , Ibuprofeno/efeitos adversos , Ibuprofeno/análise , Soluções Farmacêuticas/análise , Solubilidade , Sacarose/efeitos adversos , Sacarose/análise , Edulcorantes/análise , Ácido Valproico/efeitos adversos , Ácido Valproico/análise , Vitaminas/efeitos adversos , Vitaminas/análise
5.
Int J Urol ; 20(12): 1199-203, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23601029

RESUMO

OBJECTIVE: To compare lingual and buccal mucosa graft urethroplasty for anterior urethral stricture with respect to intraoperative, postoperative parameters and urethroplasty outcome. METHODS: From January 2011 to December 2011, a total of 30 patients with anterior urethral stricture whereas group 2 underwent dorsal onlay buccal mucosa graft urethroplasty. Patients were evaluated for postoperative, tongue protrusion, oral opening, and difficulty in speech and swallowing pain score. Surgical outcome was evaluated with pre- and postoperative work-up involving retrograde urethrogram, uroflow and urethroscopy. RESULTS: Mean age, stricture length and overall pain score were comparable in two groups. All the patients were mostly pain free by postoperative day 7. Group 1 patients had significant difficulty in speech and delayed return to normal diet as compared with group 2. The group 2 patients had a significant reduction in oral opening for the first week after surgery. In group 1, approximately 20% patients (with bilateral lingual grafts and stricture length >7 cm) complained of a change in speech character with restricted tongue movement in the long term, whereas there was no significant long-term morbidity in group 2. At mean follow up of 14.5 months, urethroplasty outcome was comparable in the two groups with one failure in group 1, and two failures in group 2. CONCLUSION: Lingual mucosa graft urethroplasty provides outcomes equivalent to those of buccal mucosa graft urethroplasty. Postoperative morbidity and long-term change in speech make it a second choice for strictures >7 cm, only for cases where buccal mucosa graft is unavailable.


Assuntos
Mucosa Bucal/transplante , Coleta de Tecidos e Órgãos/métodos , Língua/transplante , Uretra/cirurgia , Estreitamento Uretral/cirurgia , Procedimentos Cirúrgicos Urológicos Masculinos/métodos , Adolescente , Adulto , Idoso , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico , Estudos Prospectivos , Resultado do Tratamento , Adulto Jovem
6.
Contemp Clin Dent ; 12(1): 55-62, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33967539

RESUMO

BACKGROUND: Ideal pulpectomy for primary dentition demands fast, simple procedures, with short treatment times and minimal appointments. Recently, exclusive pediatric rotary files are available for use in primary teeth. There is a paucity of literature on the clinical efficacy of pediatric rotary files. Hence, this study was planned to evaluate and compare pediatric rotary files and K-files. AIM: The aim of this study was to evaluate and compare instrumentation time, obturation time, and radiographic quality of obturation using rotary systems (Kedo-S; Pro-AF Baby GOLD files) and manual (K-files) technique in primary molar pulpectomies. MATERIALS AND METHODS: Forty-five primary mandibular molars from 42 children aged 5-9 were selected. Single-visit pulpectomy was performed after dividing selected teeth into three equal groups: (i) K-files, (ii) Kedo-S files, (iii) Pro-AF Baby GOLD files. Instrumentation and obturation times were recorded during the procedure. Immediate postoperative radiographs were taken and evaluated later for obturation quality by two independent evaluators blinded to the instrumentation technique. The results were then statistically analyzed. RESULTS: Kedo-S (Group II) files required the least instrumentation time followed by Pro-AF (Group III) and K-files (Group I). The superior quality of obturation in lesser time was achieved using Pro-AF files (Group III) followed by Kedo-S (Group II) and K-files (Group I). CONCLUSION: Pediatric rotary files are efficient alternatives to hand instrumentation and can be considered as the standard of care in pulpectomies of primary teeth.

7.
Indian J Dent Res ; 30(1): 43-46, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30900655

RESUMO

CONTEXT: Autism prevalence is increasing, with current estimates at 1/68-1/50 individuals diagnosed with autism. Diagnosis is based on behavioral assessments. Early diagnosis and intervention are known to greatly improve functional outcomes in people with autism. Diagnosis, treatment monitoring, and prognosis of autistic children's symptoms could be facilitated with biomarkers to complement behavioral assessments. AIMS: The aim of this study is to compare and evaluate salivary zinc concentration in saliva samples of autistic and healthy children in mixed dentition age group. SETTINGS AND DESIGN: Cross-sectional comparative study carried out in dental college and special child school. Unstimulated whole saliva collected for finding a biomarker. SUBJECTS AND METHODS: Unstimulated whole saliva sample was collected from 10 autistic and 10 healthy children in mixed dentition age group. Diluted saliva sample was then subjected to inductively coupled plasma emission spectroscopy for the estimation of salivary zinc concentration. STATISTICAL ANALYSIS USED: Mann-Whitney U-test. RESULTS: In children with autism salivary zinc concentration showed a linear equation when compared to healthy children. CONCLUSIONS: The low salivary zinc concentration in autistic children can reveal the pathogenesis of autism.


Assuntos
Transtorno Autístico/metabolismo , Dentição Mista , Voluntários Saudáveis , Saliva/metabolismo , Zinco/metabolismo , Adolescente , Transtorno Autístico/diagnóstico , Transtorno Autístico/etiologia , Biomarcadores/metabolismo , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Projetos Piloto
8.
Low Urin Tract Symptoms ; 10(2): 131-134, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-28256100

RESUMO

OBJECTIVE: The American Urology Association symptom index (AUASI) is the most accepted tool to assess lower urinary tract symptoms (LUTS). UWIN (urgency, weak stream, incomplete void, nocturia) score is a simplified questionnaire with fewer and more distinctive options omitting three questions from AUASI. We sought to identify if UWIN is equally efficient in capturing LUTS and could replace the gold-standard AUASI. METHODS: Consecutive consenting male patients with benign prostatic hyperplasia (BPH)-LUTS were randomized to receive either UWIN/AUASI questionnaire first followed by the other. Education levels, time taken to complete, need for assistance, ease of comprehension and satisfaction to symptom assessment were assessed for each questionnaire. Correlation analysis was done for corresponding items, total and QoL scores on both questionnaires. RESULTS: Total of 294 completely filled questionnaire pairs were analyzed. Between corresponding UWIN and AUASI items, there was 93-97% correlation. When obstructive and irritative scores were added, correlation was 85% and for QOL scores 89%. Overall, AUASI required more assistance (58 vs 34%, P < 0.001), took longer to complete (11.2 vs 4.8 min, P < 0.001) and required higher educational level for comprehension (P = 0.02). Significantly higher percentage of patients preferred the UWIN and more comprehensible. CONCLUSION: UWIN is as effective in capturing LUTS as the gold-standard AUASI in spite of three questions of AUASI being omitted in UWIN. Severity of obstructive and irritative nature of LUTS and quality of life are interpreted similar to AUASI. UWIN is easier to comprehend and rapid, needing lesser assistance even with lower educational status.


Assuntos
Sintomas do Trato Urinário Inferior/etiologia , Índice de Gravidade de Doença , Transtornos Urinários/diagnóstico , Idoso , Estudos Cross-Over , Humanos , Masculino , Noctúria/etiologia , Medidas de Resultados Relatados pelo Paciente , Satisfação do Paciente , Hiperplasia Prostática/complicações , Qualidade de Vida , Inquéritos e Questionários
9.
J Clin Diagn Res ; 11(5): PC01-PC04, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28658843

RESUMO

INTRODUCTION: With advances in endourology, open stone surgery for staghorn calculi has markedly diminished. Anatrophic Nephrolithotomy (AN) is performed for complex staghorn stones which cannot be cleared by a reasonable number of Percutaneous Nephrolithotomy (PNL) attempts. AIM: To assess the indications and outcomes of AN in the modern era. MATERIALS AND METHODS: Between April 2008 and July 2015, AN was done in 14 renal units in 13 patients. In this retrospective study, demography, stone characteristics, operative details, clearance and long term outcomes were assessed. RESULTS: AN was performed for complex staghorn calculi involving pelvis and all calyces in 10 patients, infundibular stenosis in two patients and failed PNL in one patient. Mean (SD) in situ cold ischemia time was 47.64 (5.27) minutes. Retroperitoneal drain and double J stent were placed in all 13 patients. Median (IQR) estimated blood loss was 130 (75) ml. There was no perioperative mortality. Surgical site infection was seen in 2 patients and urosepsis in 2 patients. Drain was removed at a mean (SD) of 9.11 (6.15) days. Mean (SD) postoperative length of hospitalization was 15.44 (7.14) days. Stent removal was done in all patients between 2-8 weeks. Median (IQR) clearance was 95 (7.5%). There was no renal failure or new calculi during the follow up period {median (IQR): 1(3) years}. CONCLUSION: AN is effective in management of large staghorn calculi failed minimally invasive approaches and achieves 80%-100% clearance without much need for secondary interventions. Renal function is preserved and with emergence of laparoscopy and robotics, postoperative stay is minimized with expedited recovery and comparable results with open surgery.

10.
Cent European J Urol ; 70(2): 148-153, 2017 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-28721281

RESUMO

INTRODUCTION: Currently alpha1-adrenoceptor blockers (AB) are widely used as first-line therapy to improve lower urinary tract symptoms (LUTS) associated with benign prostatic hyperplasia (BPH). We compared the efficacy and safety profile of tamsulosin, alfuzosin and silodosin in LUTS due to BPH. MATERIAL AND METHODS: Consecutive consenting male patients (N = 269) undergoing medical management of BPH with AB from February 2012 to October 2015 were enrolled. Patients were randomized to a 0.4 mg tamsulosin (group T), 10 mg alfuzosin (group A) or a 8 mg silodosin (group S) by double-blind randomization. All patients were assessed for improvements and post-void residual urine (PVR) and for adverse drug events (ADE). RESULTS: IPSS showed significant improvement in Group S at the first week (11.7 ±4.18, p = 0.027) and at 3 months (7.97 ±3.84, p = 0.020). QOL showed significant improvement at 1 (2.2 ±0.76, p = 0.020), 4 (1.47 ±0.63, p <0.001) and 12 (1.2 ±0.66, p <0.001) weeks in Group S. The mean Qmax improvement was the maximum (13.76 ±2.44, p = 0.028) in Group S at 1 week. Reduction in PVR was the maximum in Group S, but it was not statistically significant. Adverse drug events (ADE) were observed in 20.07% (54/269) patients and distribution was similar in the three groups with decreasing incidence with progression of time. CONCLUSIONS: Silodosin is the most efficacious AB with rapid onset of action. Silodosin also improves the quality of life in patients with LUTS due to BPH and objectively improves maximum flow rate. However, silodosin has more adverse events when compared to tamsulosin and alfuzosin.

11.
J Int Oral Health ; 7(1): 36-9, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25709365

RESUMO

BACKGROUND: A pediatrician is a primary care physician who deals with the medical care of infants, children and adolescents. Oral health care for the subgroups detailed is certainly substantiated as an integral part of general health. There are conflicting results presented till date on the subject of knowledge, attitude and practice (KAP) of pediatricians on the consumption of pediatric liquid medicaments and the results can be divergent based on the geographical adjustments specifically with significance for industrial areas. Hence, the present study was carried out to evaluate the KAP of pediatricians toward oral health of children taking long-term pediatric liquid medicaments in Pimpri-Chinchwad area deemed and identified as Asia's largest industrial area. MATERIALS AND METHODS: A questionnaire was distributed among 50 pediatriacians practicing in Pimpri-Chinchwad, Pune city area, which consisted of questions seeking knowledge of pediatricians regarding awareness of detrimental effects of long-term pediatricians toward long-term liquid medicaments use on oral cavity, including delivery of oral hygiene instructions and regular dental checkup. The results as obtained were subjected to statistical analysis using SPSS version 16.0 for windows (Chicago Inc., USA). The statistical significance of difference was tested using Chi-square test for independence of attributes. RESULTS: About 68% were aware that long-term use of pediatric liquid medicaments can cause tooth structure defects. But only 58% advised regular dental checkups for these patients. 50% of the pediatricians prescribed the liquid medications to be taken in between two meals and 74% of the pediatricians advised rinsing mouth with water immediately after consuming pediatric liquid medicaments. However, there was no statistically significant difference seen among the values observed. CONCLUSION: The pediatricians showed reasonable awareness regarding the ill effects of the long-term use of pediatric liquid medicaments and took precautions regarding the same. However, proper oral hygiene maintenance instructions were lacking as a skill in their offerings.

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