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1.
Artigo em Inglês | MEDLINE | ID: mdl-37103527

RESUMO

BACKGROUND AND OBJECTIVE: Common variable immunodeficiency (CVID) is considered the most symptomatic type of inborn errors of immunity in humans. Along with infectious complications, which have numerous consequences, non-infectious complications are also a major challenge among CVID patients. METHODS: All registered CVID patients in the national database were included in this retrospective cohort study. Patients were divided into two groups based on the presence of B-cell lymphopenia. Demographic characteristics, laboratory findings, non-infectious organ involvements, autoimmunity, and lymphoproliferative diseases were evaluated. RESULTS: Among 387 enrolled patients, 66.4% were diagnosed with non-infectious complications; however, 33.6% had only infectious presentations. Enteropathy, autoimmunity, and lymphoproliferative disorders were reported in 35.1%, 24.3%, and 21.4% of patients, respectively. Some complications, including autoimmunity and hepatosplenomegaly, were reported to be significantly higher among patients with B-cell lymphopenia. Among organ involvement, dermatologic, endocrine and musculoskeletal systems were predominantly affected in CVID patients with B-cell lymphopenia. Among autoimmune manifestations, the frequency of rheumatologic, hematologic, and gastrointestinal autoimmunity was reported to be higher compared to other types of autoimmunity independent from the B cell-lymphopenia. Furthermore, hematological cancers, particularly lymphoma, were slightly introduced as the most common type of malignancy. Meanwhile, the mortality rate was 24.5%, and respiratory failure and malignancies were reported as the most common cause of death in our patients without significant differences between the two groups. CONCLUSION: Considering that some of the non-infectious complications might be associated with B-cell lymphopenia, therefore, regular patient monitoring and follow-up along with proper medications (besides immunoglobulins replacement therapy) are highly recommended to prevent further sequels and increase the patients' quality of life.

3.
Eur J Health Econ ; 24(4): 633-646, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35900675

RESUMO

Infectious diseases drive countries to provide vaccines to individuals. Due to the limited supply of vaccines, individuals prioritize receiving vaccinations worldwide. Although, priority groups are formed based on age groupings due to the restricted decision-making time. Governments usually ordain different health protocols such as lockdown policy, mandatory use of face masks, and vaccination during the pandemics. Therefore, this study considers the case of COVID-19 with a SEQIR (susceptible-exposed-quarantined-infected-recovered) epidemic model and presents a novel prioritization technique to minimize the social and economic impacts of the lockdown policy. We use retail units as one of the affected parts to demonstrate how a vaccination plan may be more effective if individuals such as retailers were prioritized and age groups. In addition, we estimate the total required vaccine doses to control the epidemic disease and compute the number of vaccine doses supplied by various suppliers. The vaccine doses are determined using optimal control theory in the solution technique. In addition, we consider the effect of the mask using policy in the number of vaccine doses allocated to each priority group. The model's performance is evaluated using an illustrative scenario based on a real case.


Assuntos
COVID-19 , Vacinas , Humanos , COVID-19/prevenção & controle , Controle de Doenças Transmissíveis , Vacinação , Governo , Pandemias/prevenção & controle
4.
Eur Arch Paediatr Dent ; 23(6): 953-960, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36048411

RESUMO

PURPOSE: The aim of the study was to compare the effectiveness of the audio-visual storytelling method and the "tell-show-do" (TSD) technique on reducing children's dental anxiety. METHODS: A controlled clinical trial study was performed with two experimental groups and a control group. Forty-five 6-to-9 years old children were randomly divided into the groups. Venham Picture Test and Facial Image scale were used as measurement tools. Repeated measures analysis of variance and Bonferroni post hoc test were used to evaluate the interventions. RESULTS: The results of the post hoc test showed that there was a significant difference between the mean scores of the control group and storytelling group according to both anxiety scales (p = 0.001). Also, there was a significant difference between the mean scores of the control group and TSD group according to both anxiety scales (p = 0.01). CONCLUSION: The audio-visual storytelling appears an effective, applicable method for reducing children's dental anxiety. However, it is significant to select an appropriate story and also to consider the dentist-patient relationship.


Assuntos
Comportamento Infantil , Ansiedade ao Tratamento Odontológico , Criança , Humanos , Ansiedade ao Tratamento Odontológico/prevenção & controle , Irã (Geográfico)
5.
Nanoscale ; 13(26): 11403-11413, 2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-34160516

RESUMO

A novel nanomaterial is synthesized based on the functionalization of graphene quantum dot with dimercaprol (GQD-DMC). Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and high-resolution transmission electron microscopy (TEM) are used to approve the successful synthesis of GQD-DMC. The synthesized nanomaterial is used as an electrode modifier for the sensitive and selective determination of mercury(ii) ions in real water samples. The method of evaluation is based on the pre-concentration of mercury ions on the GQD-DMC modified glassy carbon electrode, reduction of Hg(ii), and anodic stripping voltammetric measurement of these reduced ions in a buffer solution. The pre-concentration of mercury ions is driven by the affinity interaction between the surface containing functional groups of DMC and Hg(ii) ions. The GQD-DMC modified glassy carbon electrode (GQD-DMC/GCE) shows extra sensitivity and selectivity for mercury(ii) detection, which is assumed to be due to the increased surface area as well as the presence of sulfur-containing functional groups on the modified structure.

6.
BMC Med Ethics ; 21(1): 86, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32883258

RESUMO

BACKGROUND: Keeping the patients well and fully informed about diagnosis, prognosis, and treatments is one of the patient's rights in any healthcare system. Although all healthcare providers have the same viewpoint about rendering the truth in treatment process, sometimes the truth is not told to the patients; that is why the healthcare staff tell "white lie" instead. This study aimed to explore the nurses' experience of white lies during patient care. METHODS: This qualitative study was conducted from June to December 2018. Eighteen hospital nurses were recruited with maximum variation from ten state-run educational hospitals affiliated to Tehran University of Medical Sciences. Purposeful sampling was used and data were collected by semi-structured interviews that were continued until data saturation. Data were classified and analyzed by content analysis approach. RESULTS: The data analysis in this study resulted in four main categories and 11 subcategories. The main categories included hope crisis, bad news, cultural diversity, and nurses' limited professional competences. CONCLUSION: Results of the present study showed that, white lie told by nurses during patient care may be due to a wide range of patient, nurse and/or organizational related factors. Communication was the main factor that influenced information rendering. Nurses' communication with patients should be based on mutual respect, trust and adequate cultural knowledge, and also nurses should provide precise information to patients, so that they can make accurate decisions regarding their health care.


Assuntos
Comunicação , Enfermeiras e Enfermeiros , Humanos , Irã (Geográfico) , Assistência ao Paciente , Pesquisa Qualitativa
7.
Chemosphere ; 254: 126670, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32325352

RESUMO

Ultrasound-assisted bioacid leaching was examined for the extraction of valuable metals from spent lithium ion batteries (LIBs). In this work, organic acids in lemon juice were used as the leaching agent together with H2O2. Three effective factors, namely solid/liquid (S/L) ratio, lemon juice percentage, and H2O2 volume percentage, were optimized using Response Surface Methodology (RSM). The optimal conditions were found to be 0.98% (w/v) S/L ratio, 57.8% (v/v) lemon juice and 8.07% (v/v) H2O2 in the leaching liquor, achieving recovery of 100% Li, 96% Co and 96% Ni. Furthermore, the individual effects of ultrasound, H2O2 and lemon juice on metal recovery were studied and the results showed that without H2O2 or lemon juice, the metal recovery rates decreased greatly while the absence of ultrasound reduced recovery rates to a much smaller extent, indicating that both H2O2 and lemon juice were essential in the leaching process. The effect of time on the metals recoveries was examined and results showed that Li and Co recovery reached 100% with the leaching time of 35 min. The modified shrinking core modeling results suggested that chemical reaction was the rate controlling step.


Assuntos
Fontes de Energia Elétrica , Peróxido de Hidrogênio/química , Lítio/química , Ondas Ultrassônicas , Metais , Reciclagem
8.
J Helminthol ; 94: e16, 2018 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-30486905

RESUMO

A new species of Paurodontoides, P. siddiqii n. sp., is described and illustrated based on its morphological, morphometric, and molecular characters. The new species is characterized by a female 550-729 µm long, lip region continuous with body contour, stylet length 7.0-8.0 µm long or c. 1.0-1.2 times the lip region diameter, lateral fields with four smooth incisures, excretory pore at 85-125 µm from anterior end located at the base of the pharyngeal bulb or posterior to it, basal pharyngeal bulb with a short posterior extension projecting into the intestine, monodelphic-prodelphic reproductive system with prominent 19-22 µm long post-uterine sac, and elongate conoid tail with a filiform terminus. The new species is compared with two known species of the genus. It differs from the type species of the genus, P. linfordi, by having slightly shorter stylet, lateral field with smooth incisures, different position of the excretory pore, and absence of male. Compared to P. latus, the new species has a shorter body, shorter stylet, different position of the excretory pore, female tail shape and absence of male. The new species was also compared with close species of the genus Paurodontus because of lateral field marked with four lines, asymmetrical stylet knobs and absence of male. Molecular phylogenetic studies of the new species using partial sequences of 18S rDNA revealed that it forms a clade with a species of the genus Ficotylus. In phylogenetic analyses using partial sequences of the 28S rDNA D2-D3 domain, the new species formed a monophyletic group with a species of the genus Veleshkinema and Sphaerularia spp. (Sphaerulariinae).


Assuntos
Genitália/crescimento & desenvolvimento , Pinus/parasitologia , Casca de Planta/parasitologia , Tylenchida/crescimento & desenvolvimento , Tylenchida/genética , Animais , Tamanho Corporal , DNA de Helmintos/genética , DNA Ribossômico/genética , Feminino , Genitália/anatomia & histologia , Irã (Geográfico) , Masculino , Filogenia , Tylenchida/classificação , Tylenchida/isolamento & purificação
9.
Eur J Pain ; 20(10): 1753-1762, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27301294

RESUMO

BACKGROUND: Chemical stimulation of the lateral hypothalamus (LH) with carbachol induces antinociception which is antagonized by blockade of orexin receptors in some pain modulatory sites in the tail-flick test. In this study, we evaluated the role of orexin-1 and CB1 receptors in the periaqueductal gray matter (PAG), a critical pain modulatory site, in mediation of antinociceptive responses induced by LH stimulation in rats. METHODS: One hundred thirty-two adult male albino Wistar rats weighing 180-250 g were unilaterally implanted with two separate cannulae into the LH and ventrolateral PAG (vlPAG). Intra-vlPAG administration of SB334867, as a selective orexin-1 receptor antagonist (0.5, 1.5, 5, 15 and 50 nM), or AM251, as a selective CB1 receptor antagonist (1, 3, 10, 30 and 100 nM), was performed just 5 min before carbachol (125 nM) microinjection into the LH. RESULTS: Our findings showed that SB334867 or AM251 administration dose dependently prevented the development of LH-induced antinociception in rats. Treatment with two antagonists at the same time could not intensify their effects in comparison with separate administration of antagonists. CONCLUSION: It seems that antinociceptive effect of intra-LH administration of carbachol is mediated, at least partially, through the activation of orexin-1 and CB1 receptors in the vlPAG. SIGNIFICANCE: This work demonstrates a pain modulatory role of the orexinergic system via the PAG in hypothalamic-mediated analgesia suggesting that orexins can be advantageously targeted to achieve analgesia. WHAT DOES THIS STUDY ADD?: OX1 receptor antagonist (SB334867) administration into the ventrolateral periaqueductal gray matter (vlPAG) dose dependently blocked the carbachol-induced antinociception. CB1 receptor antagonist (AM251) microinjection in the vlPAG prevented carbachol-induced antinociception in a dose-dependent manner. Concurrent administration of SB334867 and AM251 into the vlPAG did not reinforce the antinociceptive responses.


Assuntos
Região Hipotalâmica Lateral/efeitos dos fármacos , Receptores de Orexina/fisiologia , Orexinas/fisiologia , Dor/etiologia , Substância Cinzenta Periaquedutal/efeitos dos fármacos , Receptor CB1 de Canabinoide/fisiologia , Animais , Benzoxazóis/farmacologia , Carbacol , Modelos Animais de Doenças , Masculino , Microinjeções , Naftiridinas , Receptores de Orexina/efeitos dos fármacos , Orexinas/antagonistas & inibidores , Dor/fisiopatologia , Dor/prevenção & controle , Medição da Dor , Piperidinas/farmacologia , Pirazóis/farmacologia , Ratos , Ratos Wistar , Receptor CB1 de Canabinoide/antagonistas & inibidores , Estimulação Química , Ureia/análogos & derivados , Ureia/farmacologia
10.
Neuroscience ; 312: 35-47, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26562432

RESUMO

Peroxisomes constitute special cellular organelles which display a variety of metabolic functions including fatty acid oxidation and free radical elimination. Abundance of these flexible organelles varies in response to different environmental stimuli. It has been demonstrated that PEX11ß, a peroxisomal membrane elongation factor, is involved in the regulation of size, shape and number of peroxisomes. To investigate the role of PEX11ß in neural differentiation of mouse embryonic stem cells (mESCs), we generated a stably transduced mESCs line that derives the expression of a short hairpin RNA against Pex11ß gene following doxycycline (Dox) induction. Knock-down of Pex11ß, during neural differentiation, significantly reduced the expression of neural progenitor cells and mature neuronal markers (p<0.05) indicating that decreased expression of PEX11ß suppresses neuronal maturation. Additionally, mRNA levels of other peroxisome-related genes such as PMP70, Pex11α, Catalase, Pex19 and Pex5 were also significantly reduced by Pex11ß knock-down (p<0.05). Interestingly, pretreatment of transduced mESCs with peroxisome proliferator-activated receptor γ agonist (pioglitazone (Pio)) ameliorated the inhibitory effects of Pex11ß knock down on neural differentiation. Pio also significantly (p<0.05) increased the expression of neural progenitor and mature neuronal markers besides the expression of peroxisomal genes in transduced mESC. Results elucidated the importance of Pex11ß expression in neural differentiation of mESCs, thereby highlighting the essential role of peroxisomes in mammalian neural differentiation. The observation that Pio recovered peroxisomal function and improved neural differentiation of Pex11ß knocked-down mESCs, proposes a potential new pharmacological implication of Pio for neurogenesis in patients with peroxisomal defects.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Hipoglicemiantes/farmacologia , Proteínas de Membrana/fisiologia , Células-Tronco Embrionárias Murinas/efeitos dos fármacos , Neurogênese/efeitos dos fármacos , PPAR gama/agonistas , Peroxissomos/efeitos dos fármacos , Tiazolidinedionas/farmacologia , Animais , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Camundongos , Camundongos Endogâmicos C57BL , Peroxissomos/fisiologia , Pioglitazona
11.
Int Nurs Rev ; 59(2): 168-74, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22591086

RESUMO

BACKGROUND: Nursing associations and organizations are deemed to be effective tools in promoting the profession. Professional nursing associations are an essential part of the nursing culture. Examining the challenges and opportunities confronting the associations would pave the way for the identification of their limitations and also would lead to more interactions among the members and the associations. METHODS: Following an extensive review of the literature and also examining the professional nursing associations in Iran, the common challenges facing the nursing associations are identified and their shared challenges with other associations in other countries have been explored. Lack of members and insufficient support from the associations, financial problems, non-professional activities of associations and lack of interactions among associations are among the important challenges that the nursing associations confront within Iran. The possibility for establishing specialized nursing associations for increasing teamwork activities can be pointed out as one of the available opportunities. CONCLUSION: Professional associations follow important priorities with regard to their objectives, which distinguishes each from the other. The clear introduction of objectives and pinpointing the convergences that might bring about clashes between them will lead to building confidence among nurses, and hopefully, increasing membership. Members' dynamic participation, and support and interactions between associations are among the measures for increasing the professional power. Researchers hope that this article could provide both nurses and professional associations with insights to support each other for the purpose of promoting professional development. Considering the insufficient research in the field, more studies are also suggested.


Assuntos
Sociedades de Enfermagem/organização & administração , Negociação Coletiva , Humanos , Relações Interprofissionais , Irã (Geográfico) , Objetivos Organizacionais , Sociedades de Enfermagem/tendências
12.
J Med Eng Technol ; 36(1): 67-71, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22188577

RESUMO

PURPOSE: With the aim of facilitating core fistulectomy of high fistula-in-ano and reducing the risk of harmful injuries to sphincter muscles, we fabricated a novel fistulectomy set. METHODS: The set circumferentially separates approximately 2.5 mm thickness of the tract by moving a special tubular blade along it and removes the separated tissues by rotating a special cannulated screw which is housed in the blade. A straight rigid probe is used for identifying the tract path and guiding the device along it. RESULTS: We used this set for circumferential excision of fistula models created in cubic pieces of fresh cow muscle with excellent results. CONCLUSIONS: With regard to results of our tests, it is anticipated that the new set will provide significant advantages in treatment of high anal fistulas, namely noticeable reduction in the diameter of fistulectomy lumen, reducing the injuries to anal sphincters, minimizing the risk of faecal incontinence and shortening the convalescence period.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório/instrumentação , Fístula Retal/cirurgia , Desenho de Equipamento , Humanos
13.
Scand J Rheumatol ; 40(5): 383-6, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21623663

RESUMO

OBJECTIVE: Behçet's disease (BD) is an inflammatory disorder of unknown cause with higher prevalence along the ancient Silk Road. BD shares epidemiological and clinical features with familial Mediterranean fever (FMF). Moreover, association of BD and certain MEFV gene mutations has been described in recent decades. We studied the role of MEFV mutations in Iranian Azeri Turkish patients with BD. METHODS: Fifty-three BD patients who met the International Study Group criteria for BD were analysed for five common MEFV mutations (M694V, V726A, M680I, M694I, and E148Q) using amplification refractory mutation system and polymerase chain reaction (PCR) restriction-digestion testing methods. A cohort of 200 healthy Azeri Turkish individuals who had been previously genotyped regarding the five common MEFV mutations served as the control group. RESULTS: Eighteen patients were found to carry a single MEFV mutation and one additional patient was compound heterozygote. There was a statistically significant difference between the patient group and ethnically matched healthy individuals regarding M694V and M680I mutations (p = 0.01 and p = 0.04, respectively). Both BD groups (carriers and non-carriers of MEFV mutations) were similar in their clinical symptoms. CONCLUSION: Definite MEFV mutations seem to be a susceptibility factor for BD in our cohort of Iranian Azeri Turkish patients.


Assuntos
Síndrome de Behçet/genética , Proteínas do Citoesqueleto/genética , Adolescente , Adulto , Síndrome de Behçet/epidemiologia , Etnicidade/genética , Etnicidade/estatística & dados numéricos , Febre Familiar do Mediterrâneo/epidemiologia , Febre Familiar do Mediterrâneo/genética , Feminino , Frequência do Gene , Predisposição Genética para Doença/epidemiologia , Heterozigoto , Humanos , Irã (Geográfico) , Masculino , Pessoa de Meia-Idade , Mutação , Prevalência , Pirina , Turquia/etnologia , Adulto Jovem
14.
J Microbiol Methods ; 82(3): 334-7, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20621134

RESUMO

Helicobacter pylori bacterial ghosts, HPBG, were generated by PhiX174 mechanism and loaded with recombinant Omp18, which were then applied in therapeutic immunization of Hp-infected C57BL/6 mice. Recombinant Omp18 loaded HPBG plus cholera toxin stimulated serum anti-Hp and Omp18-specific antibodies which resulted in significant reduction of gastric Hp colonization (P<0.05).


Assuntos
Proteínas da Membrana Bacteriana Externa/imunologia , Vacinas Bacterianas/imunologia , Infecções por Helicobacter/prevenção & controle , Helicobacter pylori/imunologia , Animais , Anticorpos Antibacterianos/imunologia , Proteínas da Membrana Bacteriana Externa/genética , Vacinas Bacterianas/administração & dosagem , Vacinas Bacterianas/genética , Feminino , Infecções por Helicobacter/imunologia , Infecções por Helicobacter/microbiologia , Helicobacter pylori/genética , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Vacinação
15.
Iran J Parasitol ; 5(1): 55-60, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22347236

RESUMO

Hydatid disease is a common and major public health issue caused by parasite Echinococcus granulosus. The highest prevalence of the parasite can be found in different parts of world like Africa, Australia, and South America. This infection can occurs in almost any part of the body. Here we present clinical, radiological, histological features and treatment of a multi vesicular osseous hydatid disease of the mandible in an Afghan 5 year old boy with a firm swelling in the right side of mandible.

16.
J Dent (Tehran) ; 7(1): 50-3, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21998775

RESUMO

Intraosseous migration is an unusual developmental dental anomaly, which demonstrates horizontal movement of unerupted teeth only affecting the permanent dentition of the lower jaw. Mandibular second premolar is the most common impacted tooth after the third molars and maxillary canines. Distal migration of the second premolar is rare and early loss of the permanent first molar is one of the most important predisposing factors of intrabony migration of this tooth. Bilateral migration of the mandibular premolars is very rare compared to unilateral migration. Hereby, we present an 18-year-old man with bilateral intrabony migration of the mandibular second premolars to the mandibular angle (at the inferior and buccal side of the mandibular canal) in the presence of first molars. The patient also had nine congenitally missing teeth without any systemic complication or abnormality in the skeleton. The teeth were surgically extracted. The clinical and diagnostic features and treatment of this case are discussed.

17.
Clin Genet ; 76(5): 477-80, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19863562

RESUMO

Familial Mediterranean fever (FMF) is an autosomal recessive autoinflammatory disorder with more than 60 disease-associated mutations in the responsible gene, MEFV. In the present study, we determined 15 MEFV mutations in Iranian Azeri Turkish FMF patients. Five hundred and twenty-four unrelated patients were tested for 15 known mutations in the MEFV gene using amplification refractory mutation system-polymerase chain reaction and polymerase chain reaction-restriction fragment length polymorphism methods. Thirty-five different genotypes were characterized among the studied patients. Of the alleles investigated, the most common mutation was p.M694V (42.4%), followed by p.V726A (17%), p.E148Q (16.2%), and p.M680I (c.2040G>C) (15.2%). The p.R761H mutation (4.7%) was found to be the most frequent among the rare mutations. The mutations p.M680I (c.2040G>A), p.I692del, p.M694del and p.K695R were not found in this cohort. The remaining mutations account for 7.7% of the identifiable mutations. Five different types of complex alleles were also identified. The results show the diversity and the frequency of the mutations in the Iranian Azeri Turkish FMF patients. The p.R761H mutation is rather prevalent in Azeri Turks; therefore, it should be included in the routine molecular diagnosis of FMF patients from this ethnic group.


Assuntos
Proteínas do Citoesqueleto/genética , Febre Familiar do Mediterrâneo/etnologia , Febre Familiar do Mediterrâneo/genética , Mutação , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Febre Familiar do Mediterrâneo/metabolismo , Humanos , Irã (Geográfico)/etnologia , Pessoa de Meia-Idade , Pirina
18.
Nanotechnology ; 19(31): 315705, 2008 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-21828797

RESUMO

Continuous wave photoluminescence (cw PL) spectroscopy has been used to study the optical properties of a set of InGaNAs epilayers and single quantum wells with nitrogen concentration less than a few per cent at different temperatures and different excitation powers. We found that nitrogen has a critical role on the emission light of InGaNAs nanostructures and the recombination mechanism. The incorporation of a few per cent of nitrogen leads to shrinkage of the InGaNAs band gap. The physical origin of such band gap reduction has been investigated both experimentally and theoretically by using a band anticrossing model. We have found that localization of excitons that have been caused by incorporation of a few per cent of nitrogen in these structures is the main explanation of such anomalous behavior observed in the low-temperature photoluminescence spectra of these nanostructures. The localization energies of carriers have been evaluated by studying the variation of the quantum well (QW) emission versus temperature, and it was found that the localization energy increases with increasing nitrogen composition. Our data also show that, with increasing excitation intensity, the PL peak position moves to higher energies (blue shift) due to the filling of localized states and capture centers for excitons by photo-generated carriers.

19.
Rev Med Chir Soc Med Nat Iasi ; 111(4): 918-21, 2007.
Artigo em Romano | MEDLINE | ID: mdl-18389780

RESUMO

The authors made an attempt at treating tuberous sclerosis (Bourneville's disease) by means of dermabrasion. The technique and postoperative course are described. The immediate results were very encouraging, but in time returned to an appearance close to the initial one. In conclusion, dermabrasion is not an appropriate treatment for tuberous sclerosis.


Assuntos
Dermabrasão , Face/cirurgia , Esclerose Tuberosa/cirurgia , Adolescente , Feminino , Humanos , Masculino , Falha de Tratamento
20.
Pathophysiology ; 12(2): 103-7, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15869871

RESUMO

Recent studies have indicated that the glutamatergic system is involved in the motivational aspects during the initiation of drug self-administration. Ascorbic acid (AA), an antioxidant vitamin, is released from glutamatergic neurons, and it modulates the synaptic action of dopamine and glutamate. In this study the AA effects on the self-administration of morphine and on the morphine withdrawal syndrome have been investigated. Wistar rats were allowed to self-administer morphine (1 mg/infusion) during 10 consecutive days for 2 h/session. The number of lever pressings was recorded. An intrapritoneal AA injection (500 mg/kg, i.p.), 30 min before morphine self-administration produced a significant decrease in the initiation of morphine self administration during all sessions. After the last test session morphine withdrawal symptom signs (MWS) were recorded after naloxone precipitation. Most of MWS (but not all) were decreased by AA application. In conclusion, AA may change the motivational processes underlying the morphine self-administration.

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