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1.
Nature ; 608(7923): 499-503, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35978130

RESUMO

Moiré superlattices in atomically thin van der Waals heterostructures hold great promise for extended control of electronic and valleytronic lifetimes1-7, the confinement of excitons in artificial moiré lattices8-13 and the formation of exotic quantum phases14-18. Such moiré-induced emergent phenomena are particularly strong for interlayer excitons, where the hole and the electron are localized in different layers of the heterostructure19,20. To exploit the full potential of correlated moiré and exciton physics, a thorough understanding of the ultrafast interlayer exciton formation process and the real-space wavefunction confinement is indispensable. Here we show that femtosecond photoemission momentum microscopy provides quantitative access to these key properties of the moiré interlayer excitons. First, we elucidate that interlayer excitons are dominantly formed through femtosecond exciton-phonon scattering and subsequent charge transfer at the interlayer-hybridized Σ valleys. Second, we show that interlayer excitons exhibit a momentum fingerprint that is a direct hallmark of the superlattice moiré modification. Third, we reconstruct the wavefunction distribution of the electronic part of the exciton and compare the size with the real-space moiré superlattice. Our work provides direct access to interlayer exciton formation dynamics in space and time and reveals opportunities to study correlated moiré and exciton physics for the future realization of exotic quantum phases of matter.

2.
Lupus ; 33(12): 1365-1372, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39150262

RESUMO

BACKGROUND: Systemic lupus erythematosus (SLE) is a chronic inflammatory multisystemic disease. Monitoring disease activity thoughtout the disease course is important for effective management and assessment of disease outcome. OBJECTIVE: To assess whether the pan-immune inflammation value (PIIV) at diagnosis could predict organ involvement and disease activity in childhood SLE (cSLE) patients after 12 months of disease onst. METHODS: This is an observational retrospective multicenter study that comprised cSLE patients seen and followed at the participating centers between January 2010 and December 2022. All patients met the EULAR/ACR-19 criteria, were immunosuppressive drug-naïve at the time of SLE diagnosis and had a minimal follow-up period of 12 months. The data included clinical and laboratory findings and disease activity using the SLEDAI-2K. Receiver operating characteristic (ROC) curves were employed to determine the optimal cut-off value of PIIV and assess its predictive potential for disease activity, and organ involvement. RESULTS: A total of 125 patients (104 female) with a median age of 16.0 (IQR 5.6) years, a median age at disease onset of 10.9 (IQR 3.0) years, and a median disease duration of 4.8 (IQR 5.3) years were included. The most frequent involved organs at diagnosis were hematological (89.6%), musculoskeletal (68.8%), mucocutaneous (63.2%), and renal (58.4%). However, at a 12-month follow-up visit, the most frequent involved organs were renal (40.0%), hematological (39.2%), musculoskeletal (15.2%), and mucocutaneous (10.4%). The median PIIV at diagnosis was 139 (IQR 229.6), while the median SLEDAI was 12 (IQR 6.5) and 3.5 (IQR 7.0) at diagnosis and 12 months, respectively. An optimal PIIV cut-off of 250 was found to be a predicative for disease activity, with a sensitivity of 45% and a specificity of 86%. The study revealed that the PIIV successfully predicted four systems in our cohort of patients. CONCLUSION: Our work suggests the PIIV might be a reasonable predictor for organ involvement and disease activity in newly diagnosed cSLE, though further research, particularly larger studies, is required to validate these findings, especially regarding organ involvement.


Assuntos
Lúpus Eritematoso Sistêmico , Humanos , Lúpus Eritematoso Sistêmico/diagnóstico , Lúpus Eritematoso Sistêmico/imunologia , Feminino , Masculino , Estudos Retrospectivos , Criança , Prognóstico , Adolescente , Curva ROC , Inflamação/diagnóstico , Índice de Gravidade de Doença , Valor Preditivo dos Testes
3.
Clin Exp Rheumatol ; 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39212133

RESUMO

OBJECTIVES: To develop an easy-to-use and efficient clinical score to identify monogenic lupus based on clinical presentations and to stratify patients who may benefit from confirmatory molecular genetic testing. METHODS: A comprehensive literature review identified 55 distinct items across 12 clinical and laboratory domains, narrowed down to the top ten by a panel of 12 expert paediatric rheumatologists with 80% consensus. The proposed score was tested in a pilot study on 10 patients with monogenic lupus and 30 control subjects with various autoimmune and autoinflammatory diseases. All patients, both with monogenic lupus and the control group, were then scored, and a receiver operating characteristic curve was employed to determine the threshold that distinguishes monogenic lupus from non-monogenic lupus. RESULTS: The clinical score comprised 10 items. Among all patients, the most frequent items were antinuclear antibody positivity and consanguinity, followed by early disease onset (<5 years), with no significant differences between monogenic lupus patients and the controls. However, the monogenic lupus patients exhibited significantly higher rates of family history of lupus, failure to thrive, cutaneous lesions, brain imaging changes, a low C1q level, and recurrent infections. Also, they achieved the highest scores compared to the controls. A score of more than three was found to be highly predictive for diagnosing monogenic lupus, with a sensitivity of 90% and a specificity of 90%. CONCLUSIONS: Our clinical score appears to be a valuable tool for the early identification of patients with monogenic lupus who may require further molecular genetic testing for confirmation.

4.
Saudi Pharm J ; 32(7): 102126, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38966679

RESUMO

In the past two decades, the world has witnessed devastating pandemics affecting the global healthcare infrastructure and disrupting society and the economy worldwide. Among all pathogens, viruses play a critical role that is associated with outbreaks due to their wide range of species, involvement of animal hosts, easily transmitted to humans, and increased rates of infectivity. Viral disease outbreaks threaten public health globally due to the challenges associated with controlling and eradicating them. Implementing effective viral disease control programs starts with ongoing surveillance data collection and analyses to detect infectious disease trends and patterns, which is critical for maintaining public health. Viral disease control strategies include improved hygiene and sanitation facilities, eliminating arthropod vectors, vaccinations, and quarantine. The Saudi Ministry of Health (MOH) and the Public Health Authority (also known as Weqayah) in Saudi Arabia are responsible for public health surveillance to control and prevent infectious diseases. The notifiable viral diseases based on the Saudi MOH include hepatitis diseases, viral hemorrhagic fevers, respiratory viral diseases, exanthematous viral diseases, neurological viral diseases, and conjunctivitis. Monitoring trends and detecting changes in these viral diseases is essential to provide proper interventions, evaluate the established prevention programs, and develop better prevention strategies. Therefore, this review aims to highlight the epidemiological updates of the recently reported viral infections in Saudi Arabia and to provide insights into the recent clinical treatment and prevention strategies.

5.
Medicina (Kaunas) ; 59(5)2023 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-37241122

RESUMO

Background and Objective: Cisplatin is a chemotherapy drug used to treat several types of malignancies. It is a platinum-based compound that interferes with cell division and DNA replication. Cisplatin has been associated with renal damage. This study evaluates the early detection of nephrotoxicity through routine laboratory tests. Materials and Methods: This is a retrospective chart review based on the Saudi Ministry of National Guard Hospital (MNGHA). We evaluated deferential laboratory tests for cancer patients treated with cisplatin between April 2015 and July 2019. The evaluation included age, sex, WBC, platelets, electrolytes, co-morbidities and interaction with radiology. Results: The review qualified 254 patients for evaluation. Around 29 patients (11.5%) had developed kidney function abnormality. These patients presented with abnormally low magnesium 9 (31%), potassium 6 (20.7%), sodium 19 (65.5%) and calcium 20 (69%). Interestingly, the whole sample size had abnormal electrolytes presenting magnesium 78 (30.8%), potassium 30 (11.9%), sodium 147 (58.1%) and calcium 106 (41.9%). Some pathological features were detected, such as hypomagnesemia, hypocalcemia and hypokalemia. In addition, infections that needed antibiotics were dominant in patients treated with cisplatin alone, representing 50% of this group. Conclusions: We report that an average of 15% of patients with electrolyte abnormalities develop renal toxicity and reduced function. Moreover, electrolytes may serve as an early indicator for renal damage as part of chemotherapy complication. This indication represents 15% of renal toxicity cases. Changes in electrolyte levels have been reported with cisplatin. Specifically, it has been linked to hypomagnesemia, hypocalcemia and hypokalemia. This study will help reduce the risk of dialysis or the need for kidney transplant. It is also important to manage any underlying conditions and control patients' intake of electrolytes.


Assuntos
Hipocalcemia , Hipopotassemia , Neoplasias , Humanos , Cisplatino/efeitos adversos , Hipocalcemia/induzido quimicamente , Hipocalcemia/complicações , Estudos Retrospectivos , Magnésio , Hipopotassemia/induzido quimicamente , Cálcio , Diálise Renal/efeitos adversos , Rim , Eletrólitos/uso terapêutico , Neoplasias/complicações , Neoplasias/tratamento farmacológico , Sódio , Potássio
6.
J Lipid Res ; 61(2): 143-158, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31818877

RESUMO

Phospholipases A2 (PLA2s) catalyze hydrolysis of the sn-2 substituent from glycerophospholipids to yield a free fatty acid (i.e., arachidonic acid), which can be metabolized to pro- or anti-inflammatory eicosanoids. Macrophages modulate inflammatory responses and are affected by Ca2+-independent phospholipase A2 (PLA2)ß (iPLA2ß). Here, we assessed the link between iPLA2ß-derived lipids (iDLs) and macrophage polarization. Macrophages from WT and KO (iPLA2ß-/-) mice were classically M1 pro-inflammatory phenotype activated or alternatively M2 anti-inflammatory phenotype activated, and eicosanoid production was determined by ultra-performance LC ESI-MS/MS. As a genotypic control, we performed similar analyses on macrophages from RIP.iPLA2ß.Tg mice with selective iPLA2ß overexpression in ß-cells. Compared with WT, generation of select pro-inflammatory prostaglandins (PGs) was lower in iPLA2ß-/- , and that of a specialized pro-resolving lipid mediator (SPM), resolvin D2, was higher; both changes are consistent with the M2 phenotype. Conversely, macrophages from RIP.iPLA2ß.Tg mice exhibited an opposite landscape, one associated with the M1 phenotype: namely, increased production of pro-inflammatory eicosanoids (6-keto PGF1α, PGE2, leukotriene B4) and decreased ability to generate resolvin D2. These changes were not linked with secretory PLA2 or cytosolic PLA2α or with leakage of the transgene. Thus, we report previously unidentified links between select iPLA2ß-derived eicosanoids, an SPM, and macrophage polarization. Importantly, our findings reveal for the first time that ß-cell iPLA2ß-derived signaling can predispose macrophage responses. These findings suggest that iDLs play critical roles in macrophage polarization, and we posit that they could be targeted therapeutically to counter inflammation-based disorders.


Assuntos
Cálcio/metabolismo , Eicosanoides/metabolismo , Fosfolipases A2 do Grupo IV/metabolismo , Macrófagos/metabolismo , Transdução de Sinais , Animais , Fosfolipases A2 do Grupo IV/deficiência , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos
7.
Rheumatol Int ; 40(1): 49-56, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31741047

RESUMO

To define the spectrum and phenotypic characteristics of systemic autoinflammatory diseases (SAIDs) other than familial Mediterranean fever (FMF) in Arab children and to delineate diagnostic evaluation. Data retrospectively collected on patients with clinical and/or genetically proven SAIDs other than FMF at 10 tertiary Arab pediatric rheumatology clinics from 1990 to 2018. The collected data comprised the clinical findings and diagnostic evaluation including genetic testing, the provided treatment and the accrual damage related to SAIDs. A total of 144 patients (93 female) with a median age at onset of 2.5 (range 0.1-12) years were enrolled. The initial diagnosis was inaccurate in 49.3%. Consanguinity rate among parents was 74.6%. The median time-to-diagnosis for all SAIDs was 2.5 (range 0.1-10) years. There were 104 patients (72.2%) with a confirmed diagnosis and 40 patients with suspected SAIDs. Seventy-two had monogenic and 66 patients with multifactorial SAIDs while six patients had undifferentiated SAIDs. The most frequent monogenic SAIDs were LACC1 mediated monogenic disorders (n = 23) followed by CAPS (12), TRAPS (12), HIDS (12), and Majeed's syndrome (6). The most frequent multifactorial SAIDs was CRMO (34), followed by PFAPA (18), and early onset sarcoidosis (EOS) (14). Genetic analysis was performed in 69 patients; 50 patients had genetically confirmed disease. Corticosteroid used for 93 patients while biologic agents for 96 patients. Overall, growth failure was the most frequent accrual damage (36%), followed by cognitive impairment (13%). There were three deaths because of infection. This study shows a heterogenous spectrum of SAIDs with a high number of genetically confirmed monogenic diseases; notably, LACC1 associated diseases. Hopefully, this work will be the first step for a prospective registry for SAIDs in Arab countries.


Assuntos
Doenças Hereditárias Autoinflamatórias/diagnóstico , Doenças Hereditárias Autoinflamatórias/epidemiologia , Acne Vulgar/diagnóstico , Acne Vulgar/tratamento farmacológico , Acne Vulgar/epidemiologia , Acne Vulgar/fisiopatologia , Adolescente , Anemia Diseritropoética Congênita/diagnóstico , Anemia Diseritropoética Congênita/tratamento farmacológico , Anemia Diseritropoética Congênita/epidemiologia , Anemia Diseritropoética Congênita/fisiopatologia , Antirreumáticos/uso terapêutico , Árabes , Artrite/diagnóstico , Artrite/tratamento farmacológico , Artrite/epidemiologia , Artrite/fisiopatologia , Artrite Infecciosa/diagnóstico , Artrite Infecciosa/tratamento farmacológico , Artrite Infecciosa/epidemiologia , Artrite Infecciosa/fisiopatologia , Artrite Juvenil/tratamento farmacológico , Artrite Juvenil/epidemiologia , Artrite Juvenil/genética , Artrite Juvenil/fisiopatologia , Barein/epidemiologia , Criança , Pré-Escolar , Consanguinidade , Doença de Crohn/tratamento farmacológico , Doença de Crohn/epidemiologia , Doença de Crohn/genética , Doença de Crohn/fisiopatologia , Estudos Transversais , Síndromes Periódicas Associadas à Criopirina/diagnóstico , Síndromes Periódicas Associadas à Criopirina/tratamento farmacológico , Síndromes Periódicas Associadas à Criopirina/epidemiologia , Síndromes Periódicas Associadas à Criopirina/fisiopatologia , Erros de Diagnóstico , Feminino , Febre/diagnóstico , Febre/tratamento farmacológico , Febre/epidemiologia , Febre/fisiopatologia , Doenças Hereditárias Autoinflamatórias/tratamento farmacológico , Doenças Hereditárias Autoinflamatórias/fisiopatologia , Humanos , Síndromes de Imunodeficiência/diagnóstico , Síndromes de Imunodeficiência/tratamento farmacológico , Síndromes de Imunodeficiência/epidemiologia , Síndromes de Imunodeficiência/fisiopatologia , Lactente
8.
J Cancer Educ ; 31(1): 131-5, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25631656

RESUMO

The purpose of this study was to randomly determine the level of awareness and knowledge among female Saudi patients about the risk factors and symptoms of breast cancer as well as any awareness about the practices for breast cancer self-examination. A random cross-sectional survey was conducted over 4 months at two private medical clinics in Riyadh, Saudi Arabia. The 4-month period was from December 2013 to March 2014. The survey instrument was a questionnaire that was both self-explanatory and user-friendly. Our study subjects included 174 randomly selected Saudi female patients with no medical history of breast cancer. These patients visited these private clinics for medical advice or for consultation on problems unrelated to breasts. Participants' perception of risk factors regarding early menses showed only 47.1 %. The most common risk factor known by the participants was a family history of breast cancer (84 %). The most widely recognized symptoms of breast cancer were occurrence of breast lumps (86.2 %) and breast pain (93.7 %). Awareness of information regarding breast self-examination (BSE) was 81.6 % in general. Many were aware of the opinion that proper and assisted knowledge about BSE can help in early detection of breast cancer. The patients were also aware that BSE is the most widely used method of screening for breast cancer in clinics and hospitals. All the participants showed sufficient knowledge about the risk factors and symptoms of breast cancer. These baseline findings are encouraging for providing more self-explanatory information (to patients) and guidance to health authorities for developing effective breast health care programs in the entire Kingdom for the female population and not only for patients visiting health care clinics for advice on other medical issues.


Assuntos
Neoplasias da Mama/prevenção & controle , Neoplasias da Mama/psicologia , Autoexame de Mama/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Adulto , Neoplasias da Mama/epidemiologia , Estudos Transversais , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Arábia Saudita/epidemiologia , Inquéritos e Questionários , Adulto Jovem
9.
Fam Community Health ; 38(4): 332-40, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26291193

RESUMO

New cases of Middle East Respiratory Syndrome Coronavirus (MERS-CoV) were reported in Gulf countries in 2014, and to date, it has reportedly infected 837 people and killed 291 globally. Awareness of an individual's knowledge and being able to predict his or her behavior is crucial when evaluating clinical preparedness for pandemics with a highly pathogenic virus. The aim of this study was to identify awareness, attitudes, and practices related to MERS-CoV among the public in Saudi Arabia. A cross-sectional study of 1147 adult subjects recruited from various shopping malls in Riyadh was conducted. All the subjects were interviewed using a questionnaire that tested their knowledge, attitudes, and use of precautionary measures in relation to the MERS-CoV pandemic. The majority of the participants showed high levels of concern and had utilized precautionary measures. After adjusting for other variables, gender was the only significant predictor of the level of concern (P < .001), while knowledge was the significant predictor of both the level of concern and precaution (P < .001). High concern translated into a higher compliance with precautionary recommendations. Frequent communication between health care providers and the public is recommended to help dispel myths about the disease and to empower the public with the information needed to help the Saudi government in containing the disease outbreak.


Assuntos
Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/prevenção & controle , Conhecimentos, Atitudes e Prática em Saúde , Coronavírus da Síndrome Respiratória do Oriente Médio , Atenção Primária à Saúde/organização & administração , Adulto , Estudos Transversais , Surtos de Doenças/prevenção & controle , Feminino , Humanos , Masculino , Pandemias , Arábia Saudita/epidemiologia
10.
Cureus ; 16(1): e52772, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38389614

RESUMO

Background and objective In the age of globalization, diseases associated with travel have emerged as a focal point of public health interest. This has become particularly relevant in Saudi Arabia after the changes in tourism policy in recent years. Primary care physicians are expected to suspect diseases of importance in certain geographic areas. They should dispense pre- and post-travel advice. This study aimed to assess the knowledge, attitudes, and practices of primary care physicians in the Al Qassim region, Saudi Arabia regarding travel medicine. Methods This cross-sectional study was conducted in the Al Qassim region, Saudi Arabia between October and November 2023. We reached out to all primary care physicians in the region regardless of their gender, nationality, and years of experience. The data were collected using a self-administered questionnaire, which was designed based on the available literature and validated by experts. Results A total of 197 physicians participated in the study; 74% were male, 46% were general practitioners, and 48% had 5-10 years of experience. More than half (51%) of the participants reported a weekly patient load of 50-100, while 47% engaged with 5-10 travelers annually; 53% provided travel health advice and a quarter of primary healthcare physicians never attended travel update sessions or conferences. In the last six months, 48% and 43% of the physicians conducted pre- and post-travel consultations respectively. Approximately 49.2% demonstrated a fair knowledge of the topic. Factors associated with fair knowledge included non-Saudi nationality, age below 30 years, minimal traveler exposure, and infrequent conference attendance (p<0.05). A positive attitude was linked to being under 30 years old, having <5 years of experience, seeing <5 travelers yearly, and possessing a fair knowledge of the topic (p<0.05). Conclusions Overall, about half of the physicians in the Al Qassim region engage with travelers and demonstrate good attitudes and practices toward travel medicine. Opening Saudi borders to tourism necessitates the inclusion of travel medicine in continuing medical education programs to prepare primary care physicians to care for travelers more efficiently.

11.
J Allergy Clin Immunol Glob ; 3(4): 100299, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39170912

RESUMO

Background: Eczema is a common inflammatory skin disease with a significant global health burden. Eczema has a significant impact on quality of life. Objective: We aimed to estimate the prevalence, severity, and risk factors associated with eczema among schoolchildren in Saudi Arabia. Methods: The standardized Global Asthma Network questionnaires and methodology were used to conduct a nationwide cross-sectional study across 20 regions in Saudi Arabia between March and April 2019. Data were collected from 137 primary schools and 140 intermediate schools by using a multistage stratified cluster sampling method. Results: The study included 3614 young children aged 6 to 7 years and 4068 adolescents aged 13 to 14 years. Current eczema was prevalent among 4.5% of the children and 5.1% of the adolescents. Severe eczema was reported in 0.8% and 0.9% of the young children and adolescents, respectively. Several factors showed significant association with eczema. Among the children, eczema was linked positively to having a history of chest infections and wheezing in early life, as well as to ever attending day care and current exposure to cats. Among the adolescents, the main potential risk factors included paracetamol use in the previous year, adherence to a lifestyle of vigorous physical activity, and current exposure to cats. Conversely, high consumption of nuts was found to be negatively associated with eczema. Conclusion: The prevalence of eczema in schoolchildren in Saudi Arabia is lower than the global average but within the average range for the Eastern Mediterranean region. Further studies in Saudi Arabia should be conducted to identify variation among different regions.

12.
Saudi Med J ; 45(8): 826-833, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39074882

RESUMO

OBJECTIVES: To assess the level of satisfaction expressed for services rendered in the public health sector to clients who were seen at outpatient departments (OPDs) and primary healthcare (PHC) facilities in Al-Qassim Health Cluster in Saudi Arabia. METHODS: This study used a comparative cross-sectional study design, and data were obtained as secondary data from The Patient's Experience Platform. Data analysis was carried out using Stata (version 16), and the significance level was 5%. RESULTS: In comparing the mean satisfaction in 9 domains, statistically significantly higher means for the PHC facilities than the OPDs were seen across 7 domains: patients navigating health facilities (p=0.008), nursing services (p<0.001), physicians' services (p=0.004), radiological services (p<0.001), personal issues (p=0.003), the pharmacy (p=0.005), and general experience (p=0.036). CONCLUSION: This study's findings are significant. They indicate that client satisfaction with services at PHC facilities was significantly higher than with services at hospital OPDs in Al-Qassim region. This underscores the need to improve the quality of services provided at OPDs to bring them to the same level as those provided by PHC facilities. Policymakers and implementers should, therefore, sustain efforts to make OPDs and PHC facilities more desirable for clients.


Assuntos
Satisfação do Paciente , Atenção Primária à Saúde , Humanos , Arábia Saudita , Satisfação do Paciente/estatística & dados numéricos , Estudos Transversais , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Adulto Jovem , Adolescente , Pacientes Ambulatoriais/estatística & dados numéricos , Ambulatório Hospitalar , Qualidade da Assistência à Saúde
13.
Sci Adv ; 10(6): eadi1323, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38324690

RESUMO

In two-dimensional semiconductors, cooperative and correlated interactions determine the material's excitonic properties and can even lead to the creation of correlated states of matter. Here, we study the fundamental two-particle correlated exciton state formed by the Coulomb interaction between single-particle holes and electrons. We find that the ultrafast transfer of an exciton's hole across a type II band-aligned semiconductor heterostructure leads to an unexpected sub-200-femtosecond upshift of the single-particle energy of the electron being photoemitted from the two-particle exciton state. While energy relaxation usually leads to an energetic downshift of the spectroscopic signature, we show that this upshift is a clear fingerprint of the correlated interaction of the electron and hole parts of the exciton. In this way, time-resolved photoelectron spectroscopy is straightforwardly established as a powerful method to access electron-hole correlations and cooperative behavior in quantum materials. Our work highlights this capability and motivates the future study of optically inaccessible correlated excitonic and electronic states of matter.

14.
Front Immunol ; 15: 1444639, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39359722

RESUMO

Introduction: We reported that Ca2+-independent phospholipase A2ß (iPLA2ß)-derived lipids (iDLs) contribute to type 1 diabetes (T1D) onset. As CD4+ and CD8+ T cells are critical in promoting ß-cell death, we tested the hypothesis that iDL signaling from these cells participates in T1D development. Methods: CD4+ and CD8+ T cells from wild-type non-obese diabetic (NOD) and NOD.iPLA2ß+/- (NOD.HET) mice were administered in different combinations to immunodeficient NOD.scid. Results: In mice receiving only NOD T cells, T1D onset was rapid (5 weeks), incidence 100% by 20 weeks, and islets absent. In contrast, onset was delayed 1 week and incidence reduced 40%-50% in mice receiving combinations that included NOD.HET T cells. Consistently, islets from these non-diabetic mice were devoid of infiltrate and contained insulin-positive ß-cells. Reduced iPLA2ß led to decreased production of proinflammatory lipids from CD4+ T cells including prostaglandins and dihydroxyeicosatrienoic acids (DHETs), products of soluble epoxide hydrolase (sEH), and inhibition of their signaling decreased (by 82%) IFNγ+CD4+ cells abundance. However, only DHETs production was reduced from CD8+ T cells and was accompanied by decreases in sEH and granzyme B. Discussion: These findings suggest that differential select iDL signaling in CD4+ and CD8+ T cells contributes to T1D development, and that therapeutics targeting such signaling might be considered to counter T1D.


Assuntos
Linfócitos T CD4-Positivos , Linfócitos T CD8-Positivos , Diabetes Mellitus Tipo 1 , Camundongos Endogâmicos NOD , Transdução de Sinais , Animais , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Camundongos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/imunologia , Fosfolipases A2 do Grupo VI/metabolismo , Fosfolipases A2 do Grupo VI/genética , Metabolismo dos Lipídeos , Camundongos SCID , Feminino
15.
Diabetes ; 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39283670

RESUMO

Type 1 diabetes (T1D) is a consequence of autoimmune destruction of ß-cells and macrophages (MΦ) have a central role in initiating processes that lead to ß-cell demise. We reported that Ca2+-independent phospholipase A2ß (iPLA2ß)-derived lipid (iDL) signaling contributes to ß-cell death. As MΦ express iPLA2ß, we assessed its role in T1D development. We find that selective reduction of myeloid-iPLA2ß in spontaneously diabetes-prone nonobese diabetic (NOD) mice (a) deceases proinflammatory eicosanoid production by MΦ, (b) favors anti-inflammatory (M2-like) MΦ phenotype, and (c) diminishes activated CD4+ and CD8+ T-cells phenotype in the pancreatic infiltrate, prior to T1D onset. These outcomes are associated with a significant reduction in T1D. Further, inhibition of select proinflammatory lipid signaling pathways reduces M1-like MΦ polarization and adoptive transfer of M2-like MΦ reduces NOD T1D incidence, suggesting a mechanism by which iDLs impact T1D development. These findings identify MΦ-iPLA2ß as a critical contributor to TID development and potential target to counter T1D onset.

16.
Infect Dis Ther ; 13(8): 1893-1905, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38967741

RESUMO

INTRODUCTION: Efficient epidemiological monitoring of virus diseases is crucial in evaluating general public health, the prevalence of specific diseases, the pattern of spread, and implementing preventative and control strategies into action. METHODS: This study analyzed data obtained from the Field Epidemiology Program (FETP) which is part of the Ministry of Health (MOH) in Saudi Arabia, which contained reported cases of infectious diseases over four years, from January 2018 to December 2021, to investigate and highlight the significant trend and incidence rate for each viral infectious disease. RESULTS: Of the reported viral infectious diseases, hepatitis B and C, dengue fever (DF), influenza, chickenpox, and measles were the highest reported viral cases over four years. For the aforementioned diseases, males were often more susceptible to viral infections than females. Except for DF, this viral infection was more common in Saudi citizens. Viral illnesses like hand, foot, and mouth disease were less prevalent, while neurological viral disorders such as acute flaccid paralysis were rarely detected. There was an overall reduction in viral cases recorded during 2020-2021, which may be attributed to the implementation of preventive measures during the Coronavirus Disease 2019 (COVID-19) pandemic or an underreporting of cases during the lockdown of that time. CONCLUSION: The prevalence of these common viral infections in the Saudi population suggests that understanding the mechanisms influencing changes in these viruses, methods of transmission, and the burden of these diseases is a priority for health policy. This understanding is necessary to develop effective intervention and preventive strategies.

17.
Infect Dis Ther ; 13(4): 667-684, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38461481

RESUMO

INTRODUCTION: Bacterial infections have a significant impact on human health; they can cause severe morbidity and mortality, particularly in susceptible populations. Epidemiological surveillance is a critical tool for monitoring the population's health and facilitate the prevention and control of infectious disease outbreaks. Knowing the burden of bacterial communicable diseases is an initial core step toward public health goals. METHODS: Saudi epidemiology surveillance data were utilized to depict the changing epidemiology of bacterial infectious diseases in Saudi Arabia from 2018 to 2021. The cumulative numbers of cases, demographics, and incidence rates were analyzed and visualized. Parametric tests were used to compare the difference in the mean values between categorical variables. Regression analysis was employed to estimate trends in disease rates over time. Statistical significance was set at p value ≤ 0.05. RESULTS: The results revealed that brucellosis, tuberculosis, and salmonellosis were the most frequently reported bacterial infectious diseases in Saudi Arabia. Males were more significantly affected by brucellosis and tuberculosis infections than females. Salmonellosis infections were more significant among Saudi citizens, while pulmonary tuberculosis was more significant in non-Saudis. Interestingly, there was a decline in the incidence rates of numerous bacterial infectious diseases during the Coronavirus Disease 2019 (COVID-19) pandemic and COVID-19 restrictions. Some bacterial infectious diseases were rarely reported in Saudi Arabia, including syphilis and diphtheria. CONCLUSIONS: The future perspective of this research is to enhance disease surveillance reporting by including different variables, such as the source of infection, travel history, hospitalization, and mortality rates. The aim is to improve the sensitivity and specificity of surveillance data and focus on the mortality associated with bacterial pathogens to identify the most significant threats and set a public health priority.

18.
J Family Med Prim Care ; 12(11): 2786-2796, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38186826

RESUMO

Background: The specialty of family medicine, established in Saudi Arabia in the 1980s, has rapidly progressed in healthcare settings and is increasingly utilized by the population as well as recent MBBS graduates. Universally, there is ambiguity in the duration, curriculum, and assessment methods used in family medicine specialization programs. Methodology: A cross-sectional study was conducted among 183 fresh graduates from a 3-year and 4-year residency program. Data were collected using electronic forms, which were subsequently transferred to Microsoft Excel. Following appropriate coding, the data were transferred to SPSS for analysis. The dataset was then cleaned, and statistical tests, such as Chi-square and independent t-tests, were used to draw inferences. Results: Males (50.3%) and females (49.7%) had almost equal distribution in the study. Overall, 67.6% of respondents had passed the final exam; the pass percentage was 69.3% for the 3-year residency program and 66.4% for the 4-year program. The overall mean score for perceived achievement of SaudiMED-FM 2020 competencies was 23.06 ± 5.52 out of a total score of 30. On comparing the 3-year versus 4-year residency program, there was no statistically significant difference between perceived competency scores and professional satisfaction scores. Among the study participants, 19 (10.4%) had 'serious burnout', and 22 (12%) had 'extremely serious burnout'. Professional satisfaction was significantly associated with burnout (P = 0.006). Conclusions: Based on the study results, there was no significant difference regarding academic performance, perceived competencies, and professional satisfaction among the graduates of the 3-year versus 4-year residency program. Approximately more than half of the graduates had suffered from burnout which was reported more by the females and those with financial issues. The majority of the respondents suggested improvements in clinical rotation and assessment methods.

19.
Saudi J Kidney Dis Transpl ; 34(6): 576-591, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-38725208

RESUMO

Renal involvement of systemic lupus erythematosus needs aggressive treatment. Despite the development of multiple international guidelines, differences in practices exist. This study aimed to explore the current practices of pediatric rheumatologists and nephrologists for the diagnosis, management, and monitoring of lupus nephritis (LN) in Saudi Arabia through a survey. Among the 61 respondents, 54.1% were pediatric nephrologists and 49.9% were pediatric rheumatologists. Predominantly, the participating physicians received training either nationally (57%) or in North America (45%). Most of the respondents (77%) did not have a combined rheumatology-nephrology clinic, primarily because of space or time limitations (75%), or a lack of the other specialty (13%). In terms of the decision to request a renal biopsy, the most common factors were nephrotic-range proteinuria (85%) and a lower level of proteinuria associated with hypocomplementemia or elevated anti-double-stranded (ds) DNA (73%). There was marginal agreement over monitoring the disease's activity and treatment response; Complements 3 and 4, anti-dsDNA, protein-creatinine ratio, and estimated glomerular filtration rate were the most popular parameters. The main reason for repeating a renal biopsy was a new renal manifestation that was inconsistent with the previous biopsy. There was considerable variability in the induction therapies used to initiate and taper corticosteroids and conventional immunosuppressive drugs. Most respondents (91%) used angiotensin-converting enzyme agents to control proteinuria. Considerable agreement exists among Saudi physicians managing children with LN but significant variations exist regarding the therapeutic strategies. Additional endeavors are needed to establish a unified national clinical approach for managing LN in children.


Assuntos
Nefrite Lúpica , Nefrologistas , Padrões de Prática Médica , Humanos , Nefrite Lúpica/diagnóstico , Nefrite Lúpica/terapia , Nefrite Lúpica/tratamento farmacológico , Nefrite Lúpica/epidemiologia , Arábia Saudita/epidemiologia , Criança , Biópsia , Reumatologistas , Pesquisas sobre Atenção à Saúde , Masculino , Feminino , Imunossupressores/uso terapêutico
20.
Cureus ; 15(3): e36580, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37095812

RESUMO

One of the rare tumors of the salivary gland is known as basal cell adenoma (BCA). Only a small percentage of salivary gland tumors affect the minor salivary gland of the oral cavity while the majority are found in the parotid gland. We present a rare case of BCA involving the left buccal mucosa of a 45-year-old female. Magnetic resonance imaging (MRI) showed well defined solid mass measuring 1.9 x 1.5 cm in the left buccal space inseparable from the buccinator muscle. The T2-weighted image demonstrates a hyperintense signal post-contrast. Ultrasound-guided fine needle aspiration cytology revealed cellular basaloid neoplasm of uncertain malignant potential. Thereafter excision of the mass was performed through a transoral approach under general anesthesia. Histopathology of the mass showed encapsulated basal cell neoplasm in favor of BCA. The patient was doing well after the surgery and has intact facial nerve and adjacent nerves such as the auriculotemporal nerve and great auricular nerve with no complications then she kept on routine clinic follow-ups, and the surgical site recovered successfully. Therefore, we conclude that MRI and biopsy provide useful information to differentiate between benign adenoma and malignant adenocarcinoma. BCA should be considered in a differential diagnosis of an isolated neck mass. Surgical excision demonstrates an excellent prognosis.

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