Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 28
Filtrar
1.
BMC Oral Health ; 24(1): 93, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38229132

RESUMO

BACKGROUND: Estrogen replacement therapy (ERT) is a common hormonal treatment for postmenopausal women, aimed at alleviating menopausal symptoms and reducing the health risks associated with estrogen deficiency. However, the impact of ERT on temporomandibular disorders (TMDs) remains unclear. This systematic review aims to evaluate the relationship between ERT and TMDs, including TMD occurence, pain, and associated symptoms. METHODS: A comprehensive search of seven electronic databases was conducted using predefined search terms and Boolean operators. Inclusion criteria encompassed studies examining the association between ERT and TMDs. Two independent reviewers screened the identified articles, extracted data, and assessed the risk of bias using the RoB -2 tool. RESULTS: Search strategy identified a total of 3 articles which met the inclusion criteria. The included studies investigated the impact of ERT on TMD occurrence and its related symptoms. The analysis revealed no significant association between ERT and TMD occurrence. A significant dose relationship was noted in one of the studies while another mentioned the possible relationship of TMD with educational status. Risk of bias among the studies was low, and the overall quality of evidence was deemed to be high. CONCLUSION: This systematic review suggests that there is no conclusive evidence supporting an increased risk of TMDs among women receiving ERT. The findings indicate that ERT is unlikely to have a noticeable impact on TMDs. However, due to the limited number of studies available, further research is warranted to strengthen these conclusions and explore potential factors that may influence the relationship between ERT and TMDs.


Assuntos
Terapia de Reposição de Estrogênios , Transtornos da Articulação Temporomandibular , Feminino , Humanos , Escolaridade , Terapia de Reposição de Estrogênios/efeitos adversos , Dor/etiologia , Transtornos da Articulação Temporomandibular/complicações
2.
BMC Oral Health ; 21(1): 446, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34526008

RESUMO

BACKGROUND: The psychometric properties of self-administered instruments for measuring patient satisfaction with removable dentures should be tested before inviting patients to express their opinions. This study aimed to evaluate the validity and reliability of new instruments in the Arabic language that measure patient satisfaction with all types of removable dentures. METHODS: A three-step methodology was used to translate and test the instruments. In step one, the instruments were translated from tested German instruments to develop the pilot questionnaires. In step two, the face validity of the pilot questionnaires was tested through three rounds of interviews. There were 15, 13, and 15 participants per round, respectively. At the end of every round, the results of the interviews were discussed with an expert panel. The expert panel confirmed the form and the type of questionnaires' adjustments before a new round of interviews began. At the end of step two, the final form of the questionnaires was reached. In step three, 235 questionnaires were distributed to 133 participants to estimate the construct validity of the upper jaw and the lower jaw questionnaires. After one week, the participants were asked to complete the questionnaires again. A total of 102 questionnaires were returned and used to assess the instruments' reliability. Factor analysis was used to assess the construct validity. The intraclass correlation coefficient and Cronbach's alpha were used to estimate the reliability and suitability of the items in the indexes. RESULTS: The result of step one was two pilot questionnaires. The pilot questionnaires were adjusted in step two. At the end of step two, the questionnaires proved to have good face validity. Factor analyses in step three revealed that only one factor could be retained. The one-factor model explained 60.95% and 63.06 of the total variance of the upper jaw and lower jaw questionnaires, respectively. The items in every questionnaire shared the same cluster and could be summed to form an upper jaw index and lower jaw index that reflected patient satisfaction with removable dentures. Cronbach's alpha values indicated excellent internal consistency and reliability for the upper jaw questionnaire (α = 0.91) and the lower jaw questionnaire (α = 0.92). Intraclass correlation coefficient values ranged from 0.72 to 0.95, which can be considered "moderate" to "excellent". CONCLUSIONS: The Arabic version of questionnaires and indexes assessing patient satisfaction with upper and lower removable dentures are reliable and valid self-administered instruments.


Assuntos
Idioma , Satisfação do Paciente , Prótese Parcial , Humanos , Psicometria , Reprodutibilidade dos Testes , Inquéritos e Questionários
3.
J Evid Based Dent Pract ; 21(1): 101530, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-34051952

RESUMO

ARTICLE TITLE AND BIBLIOGRAPHIC INFORMATION: Saliva in the Diagnosis of COVID-19: A Review and New Research Directions. Fernandes LL, Pacheco VB, Borges L et al. Journal of Dental Research. 2020. https://doi.org/10.1177/0022034520960070. SOURCE OF FUNDING: Hospital Israelita Albert Einstein and Universidade Cruzeiro do Sul, São Paulo, Brazil. The authors have no actual or potential conflicts of interest. TYPE OF STUDY/DESIGN: Systematic review.


Assuntos
COVID-19 , Saliva , Brasil , Humanos , Nasofaringe , Faringe , SARS-CoV-2
4.
PeerJ ; 12: e16732, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38188167

RESUMO

Objective: This study aims to assess and compare the potential of advanced nano/micro delivery systems, including quantum dots, carbon nanotubes, magnetic nanoparticles, dendrimers, and microneedles, as theranostic platforms for oral cancer. Furthermore, we seek to evaluate their respective advantages and disadvantages over the past decade. Materials and Methods: A comprehensive literature search was performed using Google Scholar and PubMed, with a focus on articles published between 2013 and 2023. Search queries included the specific advanced delivery system as the primary term, followed by oral cancer as the secondary term (e.g., "quantum dots AND oral cancer," etc.). Results: The advanced delivery platforms exhibited notable diagnostic and therapeutic advantages when compared to conventional techniques or control groups. These benefits encompassed improved tumor detection and visualization, enhanced precision in targeting tumors with reduced harm to neighboring tissues, and improved drug solubility and distribution, leading to enhanced drug absorption and tumor uptake. Conclusion: The findings suggest that advanced nano/micro delivery platforms hold promise for addressing numerous challenges associated with chemotherapy. By enabling precise targeting of cancerous cells, these platforms have the potential to mitigate adverse effects on surrounding healthy tissues, thus encouraging the development of innovative diagnostic and therapeutic strategies for oral cancer.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Neoplasias Bucais , Nanotubos de Carbono , Humanos , Medicina de Precisão , Neoplasias Bucais/diagnóstico , Transporte Biológico , Sistemas de Liberação de Fármacos por Nanopartículas
5.
Artigo em Inglês | MEDLINE | ID: mdl-36833792

RESUMO

The highly infectious severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) caused the coronavirus disease 2019 (COVID-19) pandemic, which affects the lives of people worldwide in a variety of unprecedented ways [...].


Assuntos
COVID-19 , Humanos , SARS-CoV-2 , Pandemias
6.
PeerJ ; 11: e14949, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36890871

RESUMO

Background: The aim of this systematic review is to determine microRNAs (miRs) that are differently expressed between diseased pulpal and periapical tissues. Design: This systematic review used PubMed, Scopus, EBSCO, ProQuest, Cochrane database as well as manual searching to extract studies from January 2012 up to February 2022. Results: A total of 12 studies met the eligibility criteria were included. All selected studies were of case-control type. Twenty-four miRNAs associated with apical periodontitis, 11 were found to be upregulatedand 13 were downregulated. Four out of the 44 miRs associated with pulpal inflammation were upregulated, whereas forty were downregulated. Six miRs, namely hsa-miR-181b, hsa-miR-181c,hsa-miR-455-3p,hsa-miR-128-3p, hsa-miR199a-5p, and hsa-miR-95, exhibited considerable downregulation in both periapical and pulp tissues. Conclusion: MiRs have been investigated for their role in pulpal and periapical biology and may be utilised in diagnostic and therapeutic purposes. Further investigations are required to determine why certain irreversible pulpitis situations progress to apical periodontitis and others do not, based on the various miR expressions. Moreover, clinical and laboratory trials are needed to support this theory.


Assuntos
MicroRNAs , Periodontite Periapical , Humanos , Perfilação da Expressão Gênica , MicroRNAs/genética , Regulação para Baixo/genética , Inflamação/genética
7.
Retina ; 32(10): 2034-8, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22653544

RESUMO

PURPOSE: To evaluate the incidence of retinal redetachment after the removal of silicone oil endotamponade for complicated retinal detachment and identify possible factors affecting outcome. METHODS: This is a retrospective review of 173 patients who underwent pars plana vitrectomy with silicone oil tamponade for complex retinal detachment and subsequent removal of silicone oil (ROSO). The outcome factors studied included anatomical success, best-corrected visual acuity and intraocular pressure pre- and post-ROSO. RESULTS: Anatomical success was achieved in 167 of the 173 eyes (96.5%) after ROSO. The mean duration of silicone oil tamponade was 70 ± 48 weeks (median, 56 weeks; mode, 48 weeks). The cause for primary retinal detachment was proliferative diabetic retinopathy in 36 (20.8%) and proliferative vitreoretinopathy in 137 of 173 cases (79.2%). Best-corrected visual acuity of greater than 20/100 was achieved in 83 cases (49.4%) at 3 months after ROSO. Levene's test for equality of variances was used to determine the association between previous unsuccessful retinal surgeries and redetachment (P = 0.523) and between duration of endotamponade and anatomical success (P = 0.451). CONCLUSION: The incidence of retinal redetachment after ROSO in our study was 3.46%. Aggressive removal of the vitreous base, performing retinotomies, ensuring complete silicone oil filling for adequate tamponade, and argon retinopexy can lead to low complication rates and improved outcomes.


Assuntos
Drenagem/métodos , Tamponamento Interno , Descolamento Retiniano/diagnóstico , Descolamento Retiniano/etiologia , Óleos de Silicone , Vitrectomia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Incidência , Pressão Intraocular/fisiologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Recidiva , Descolamento Retiniano/cirurgia , Estudos Retrospectivos , Fatores de Tempo , Acuidade Visual/fisiologia , Adulto Jovem
8.
Am J Case Rep ; 23: e933750, 2022 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-35132053

RESUMO

BACKGROUND Neisseria elongata is a infrequent cause of infective endocarditis (IE). Although considered a commensal bacterium of the human nasopharynx, N. elongata has been shown to be the cause of significant disease in humans, namely endocarditis, osteomyelitis, and septicemia. CASE REPORT We report the case of a 53-year-old man with a past medical history of mechanical aortic valve who presented to the hospital for evaluation of eleven days of recurrent and relapsing fevers and was admitted for severe sepsis with concern for endocarditis. Blood cultures revealed N. elongata bacteremia, and an echocardiogram did not show any vegetations, although it was limited by mechanical aortic valve shadowing. The patient recovered after six weeks of treatment with intravenous ceftriaxone and oral ciprofloxacin. CONCLUSIONS Clinicians should be aware of the possibility of the previously considered non-pathogenic N. elongata as a source of IE caused by gram-negative organisms, as it can potentially cause severe disease and multiple complications. Our case additionally highlights that IE has highly variable clinical presentations. Thus, it is essential to utilize the Duke criteria as only a clinical guide for the diagnosis of IE rather than a substitute for clinical judgment and the decision to treat a patient with suspected IE.


Assuntos
Bacteriemia , Endocardite Bacteriana , Endocardite , Neisseria elongata , Valva Aórtica/diagnóstico por imagem , Bacteriemia/complicações , Bacteriemia/diagnóstico , Endocardite Bacteriana/diagnóstico , Endocardite Bacteriana/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade
9.
Am J Case Rep ; 23: e937271, 2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36355628

RESUMO

BACKGROUND Chronic prosthetic joint infection (PJI) is a devastating complication following total joint arthroplasty, resulting in significant morbidity and mortality. The criterion standard of treatment for chronic PJI is two-stage revision arthroplasty consisting of complete hardware removal, thorough irrigation and debridement, placement of an antibiotic spacer, prolonged intravenous antibiotics based on culture sensitivities, and revision total knee arthroplasty once the infection resolves. The most common organism implicated in chronic PJI is Staphylococcus aureus. CASE REPORT In this report, we have summarized the case of a 75-year-old woman who developed chronic PJI caused by an unusual organism, Streptococcus gordonii, 1 year after a right total knee arthroplasty. S. gordonii is a gram-positive organism that is an oral flora and a colonizer of human teeth. This organism is known to create biofilm on the human teeth, more commonly known as dental plaque. S. gordonii has the ability to travel to extraoral sites and cause infection. It has been found to be a cause of subacute bacterial endocarditis, but it has been rarely described in the literature as a cause of prosthetic joint infection. Treatment of S. gordonii requires a tailored approach. CONCLUSIONS This case report highlights the clinical presentation, diagnosis, and treatment of chronic prosthetic joint infection caused by S. gordonii and identifies a rare cause of PJI that is not well documented in the literature. Streptococcal PJI portends a poorer prognosis, and identification of this organism is crucial for prompt treatment and improved outcomes for PJI.


Assuntos
Artrite Infecciosa , Artroplastia do Joelho , Infecções Relacionadas à Prótese , Feminino , Humanos , Idoso , Streptococcus gordonii , Infecções Relacionadas à Prótese/diagnóstico , Infecções Relacionadas à Prótese/terapia , Infecções Relacionadas à Prótese/etiologia , Desbridamento/métodos , Artrite Infecciosa/complicações , Artroplastia do Joelho/efeitos adversos , Antibacterianos/uso terapêutico
10.
Case Rep Infect Dis ; 2022: 3377331, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35656361

RESUMO

Raoultella planticola, a Gram-negative bacterium, is a nonmotile rod usually found in soil and aquatic environments. It can be found in association with gastrointestinal malignancy. Enterococcus casseliflavus is a rare vancomycin-resistant Enterococcus that is responsible for some bacteremia. Our case describes a unique presentation of colonization with both R. planticola and E. casseliflavus isolated from the biliary stent isolates of a patient with known pancreatic malignancy and concomitant E. casseliflavus bacteremia. This is the first case ever reported of infection with both species.

11.
Eur J Dent ; 2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36535660

RESUMO

OBJECTIVES: Dental students must complete two stages of training, namely, preclinical training on phantom head models and clinical training on actual patients to acquire the practical skills required by their Bachelor of Dental Surgery program.Our objectives are to evaluate the level of improvement of the manual skills obtained by third-year dental students after one full academic year of preclinical training courses using dexterity tests under direct and indirect vision and to compare the improvement among male and female dental students under the same conditions. MATERIALS AND METHODS: A total of 72 preclinical students participated in our cohort trial, each of whom was assigned a random identification number that was only known to the researchers. After the beginning of the academic year, the experiment was performed under identical conditions for both the O'Connor Tweezer Dexterity Test and the Purdue Pegboard Test. The examinations were conducted at two distinct times: T0 before phantom laboratory training (the beginning of preclinical sessions) and T1 after phantom laboratory training (9 months after T0). STATISTICAL ANALYSIS: Signed-rank test of Wilcoxon over two separate periods (T0 and T1), comparisons were made between the direct and indirect visual dexterity test scores. In addition, the Mann-Whitney U test was used to compare results across gender. The statistical significance (p-value) was set at below 0.05 with a confidence level of 95%. RESULTS: A statistically significant difference was detected between the T0 and T1 assessments on the Purdue Pegboard Test and the O'Connor Tweezer Dexterity Test for all selected dentistry students in both direct and indirect conditions (p < 0.001). CONCLUSION: Further investigation in other dental departments or schools, particularly those with different entry standards, is required prior to making a definitive conclusion about the use of these dexterity assessments as predictors of prospective dental students' performance.

12.
Int Dent J ; 72(2): 249-256, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34226066

RESUMO

OBJECTIVE: The aim of this research was to determine the relationship and prevalence of taste and smell dysfunction in patients with COVID-19 in the United Arab Emirates (UAE) population. METHODS: Enrolled participants were interviewed online via a phone call after obtaining their informed consent. Quantification of smell, taste, and other sensations before, during, and after COVID-19 infection was correlated with the severity of COVID-19 symptoms. RESULTS: A total of 500 patients with (mild-severe) COVID-19 completed the survey. A total of 26.4% were asymptomatic, and 21.4% were classified as paucisymptomatic with less severe symptoms. Almost equal proportions of the studied population experienced extreme taste sensation reductions (43%) and loss of smell sensation (44%). Statistically significant drastic decreases in smell and taste senses were seen among younger individuals. The magnitude of reduction in both sense changes increased steeply from the asymptomatic group to the paucisymptomatic group to the symptomatic group. CONCLUSIONS: Sudden anosmia or ageusia need to be recognised for early detection of COVID-19 infection to identify otherwise hidden carriers, thus favoring an early isolation strategy that will restrict the spread of the disease.


Assuntos
Ageusia , COVID-19 , Ageusia/epidemiologia , Ageusia/etiologia , Anosmia/epidemiologia , Anosmia/etiologia , COVID-19/epidemiologia , Humanos , Prevalência , Emirados Árabes Unidos/epidemiologia
14.
F1000Res ; 10: 442, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35136572

RESUMO

Adequate adoption of evidence-based practice is deeply rooted in accessing methodological quality and completeness of systematic reviews and meta-analyses reporting. Nonetheless, this assumption might be flawed if the methodological quality assessment has not been properly conducted. Taking the former statement into consideration, this correspondence article encourages the improvement of future tertiary manuscripts, especially in the field of restorative dentistry. Thus, this article addresses an overview of reviews in restorative dentistry as an example of evaluating tertiary evidence for increasing the awareness of reviewers, authors, and readers.


Assuntos
Odontologia , Revisões Sistemáticas como Assunto
15.
Case Rep Infect Dis ; 2021: 6699046, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33747580

RESUMO

Sepsis due to Actinomyces odontolyticus (A. odontolyticus) is an extremely rare condition that has been reported only a handful of times. In this report, we showcase an 83-year-old male who had a complication of neobladder procedure and developed sepsis due to A. odontolyticus that was successfully treated with a prolonged course of doxycycline.

16.
F1000Res ; 10: 473, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-36703700

RESUMO

Background: We live in a time where traditional education has rapidly incorporated online modalities due to the recent SARS-CoV-2 (COVID-19) safety measures such as social distancing. Regardless of these challenges, health education constantly strives to implement the best technologies available for an effective student deep learning outcome. Virtual (VR) and augmented reality (AR) in the dental pre-clinical stage may help stimulate students to better understand the foundation material prescribed in the curriculum. Most visual material available for students is still mainly based on 2D graphics. Thus, this study will attempt to evaluate the students' perceptions about implementing VR/AR technologies in the learning setting. Methods: A single-group pretest-posttest design will be implemented where students will be exposed to VR/AR and fill out two questionnaires, one before and one after the exposure. Conclusions: This project is intended to start once the institutional ethical approval is obtained. It is expected that the analysis from the current project will provide recommendations to improve the students' academic curriculum pre-clinical experience. The recommendations will be provided in the form of at least three scientific publications, with one publication for each subject area intended to be evaluated (i.e., head and neck anatomy, dental anatomy, and removable prosthodontics).

17.
Clin Cosmet Investig Dent ; 13: 1-10, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33442299

RESUMO

OBJECTIVE: The main aim of this present systematic review is to ascertain whether a conservative endodontic cavity (ConsAC) has a better fracture resistance than a traditional access cavity (TradAC) in endodontically treated molars. MATERIALS AND METHODS: Three independent reviewers researched without limits in multiple engines: PubMed, ScienceDirect, Scopus, ResearchGate, EBSCOhost, Wiley Online Library, and Google Scholar, in addition to reference and hand search. Articles were chosen according to a certain inclusion and exclusion criteria, which, in brief, are in vitro studies assessing the fracture resistance difference between ConsAC and TradAC performed on extracted sound human molar teeth. A quality assessment criteria was produced to evaluate the chosen articles and categorized them according to their risk of bias into low, moderate and high. RESULTS: Out of a total of 105 studies, which were obtained from seven different search engines, only eight in vitro studies were included after eliminating the duplicates followed by the application of the eligibility criteria. Five of the articles showed low risk of bias while the others revealed a moderate risk of bias. CONCLUSION: To sum up, there is insufficient evidence to give a final decision whether ConsAC is more advantageous than TradAC in terms of fracture resistance and further studies regarding this topic are needed.

18.
Int J Dent ; 2021: 6685437, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33883998

RESUMO

OBJECTIVES: Natural folk medicines with antimicrobial effects have been under investigation during the past decades. The aim of this study was to evaluate the teeth whitening and antimicrobial effects of ethanol extract of Persian walnut "Juglans regia" barks. MATERIALS AND METHODS: Minimum inhibitory concentration (MIC) was determined using a broth microdilution assay which was conducted through a 2-fold serial dilution method, and a whitening experiment was done in vitro on extracted teeth, with a pH test being performed on 2-fold dilutions of the ethanol extract. RESULT: It was found that the MIC for Enterobacter and E. coli and Staphylococcus and Pseudomonas was found to be 5 mg/ml and 2.5 mg/ml, respectively. Both dilutions were found to be acidic, and the extract of Juglans regia bark also demonstrated the ability of teeth whitening. CONCLUSION: This study supports the use of Juglans regia bark as a natural product in dentistry because of the confirmed antimicrobial ability as well as its whitening effect. Clinical Relevance. Herb extract might be incorporated within commercially available kinds of toothpaste to enhance its whitening and antimicrobial effects.

19.
PeerJ ; 9: e12214, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34631321

RESUMO

OBJECTIVE: The goal of this systematic review and meta-analysis is to determine the performance of 4% Articaine vs. 2% Lidocaine for mandibular and maxillary block and infiltration anaesthesia in patients with irreversible pulpitis (IP). METHODS: PubMed/MEDLINE, Cochrane Central Register of Controlled Trials, Web of Science, Google Scholar, and Open Gray were used to conduct a thorough literature search. A manual search of the reference lists of the publications found was also carried out. Two reviewers critically evaluated the papers for inclusion and exclusion criteria, and data extraction was done on the selected publications. The Cochrane Collaboration Tool and the Minors checklist were used to assess the quality of the selected studies for randomised controlled trials (RCTs) and non-randomised studies, respectively. The RevMan software was used to perform a meta-analysis of the pooled data and subgroups according to the technique of anaesthetic solution delivery, as well as a sensitivity analysis (P < 0.05). RESULTS: A total of twenty-six papers were included in the qualitative synthesis, with twenty-two of them being included in the meta-analysis. There were fifteen studies with a low potential for bias, three with a moderate potential for bias, and seven with a high potential for bias. The combined results of the 19 trials in the tooth level unit revealed that 4% articaine had a success rate 1.37 times greater than 2% lidocaine for mandibular teeth (RR, 1.37; 95% CI [1.17-1.62]; P = 0.0002). For the maxillary buccal infiltration method, the combined results from the three trials revealed that 4% articaine resulted in a success rate 1.06 times greater than 2% lidocaine (RR, 1.06; 95% CI [0.95-1.2]; P = 0.3). Excluding subgroups with a single study in sensitivity analysis for mandibular teeth revealed a substantial improvement in the success rate of the articaine group in treating IP when compared to the lidocaine group. CONCLUSION: The findings of this meta-analysis back up the claim that articaine is more effective than lidocaine in providing anaesthesia in patients with IP. PROSPERO Registration No.: CRD42020204606 (https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42020204606).

SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa