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1.
Cureus ; 16(6): e61632, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38966445

RESUMO

INTRODUCTION: In the past, fertility concerns have predominantly revolved around the effect of a woman's age on the quality of her eggs and the success of her pregnancy. While men generally retain their ability to father children throughout their lives, there is evidence suggesting a decline in natural conception rates as paternal age increases. A growing body of research indicates a potential link between advanced paternal age (APA) and various adverse outcomes, including changes in sperm genetics, reduced conception rates, higher rates of miscarriage, lower live birth rates, and even long-term health consequences in offspring. However, it remains unclear whether there is an association between APA and the effectiveness of assisted reproductive technology (ART). This study aims to shed light on the relationship between APA and semen parameters. METHODOLOGY: This is a retrospective, descriptive study analyzing data from electronic medical records of men undergoing ART at a fertility clinic in Saudia Arabia (2017-2022). Men aged 21-60 with at least one semen analysis and no missing data/hormonal treatment were included. Data on age and semen parameters (count, motility, and morphology) were extracted and analyzed using Jeffreys's Amazing Statistics Program (JASP; University of Amsterdam, Amsterdam, Netherlands) (descriptive statistics, Spearman's rank correlation). RESULTS: Analysis of 1506 men undergoing ART revealed a mean age of 37 years (SD=6.94) and a mean sperm count of 55.0 million/mL (SD=46.05). The correlation between age and sperm count indicates a minimal association (r=0.075, p<0.01); moderate positive correlations were observed between sperm count and motility (r=0.406); count and morphology (r=0.543); and motility and morphology (r=0.458). CONCLUSION: Age may not be a major factor in overall sperm parameters for this population, but a strong positive correlation was observed between sperm count, motility, and normal morphology. These findings suggest that these semen parameters are interconnected, with higher sperm counts potentially indicating better overall sperm quality.

2.
J Pharm Bioallied Sci ; 16(Suppl 1): S702-S703, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38595381

RESUMO

Objectives: To assess a bracket-bonding system's shear bond strength cured with dissimilar light-curing units at different time intervals. Materials and Method: Sixty premolar teeth removed for orthodontic purposes were categorized into four types based on the light-curing unit and exposure times used. The specimens in the halogen group were exposed to light for 15 (Group I) and 30 (Group II) sec, respectively. The specimens were exposed to light for 10 (Group III) and 15 sec in the LED group (Group IV). The amount of adhesive still present on the teeth was measured using a stereomicroscope at a magnification of 10 and was then assessed with the help of adhesive remnant index (ARI). Result: The group with the highest mean SBS was in Group II followed by Group I, Group III, and the group with the lowest mean SBS. The ARI was unaffected by the light-curing technique, with score 2 predominating. Conclusion: In all groups, polymerization using halogen and LED led to SBS values that were clinically suitable for orthodontic procedures.

3.
Adv Ther ; 41(4): 1419-1435, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38356106

RESUMO

INTRODUCTION: Respiratory syncytial virus (RSV) represents a considerable burden on the healthcare system and hospital resources. This study explored the impact of universal immunoprophylaxis with long-acting monoclonal antibody (nirsevimab) during infants' first RSV season on RSV-induced health events and related costs in the Kingdom of Saudi Arabia (KSA). METHODS: The burden of RSV-induced health events and related costs under the current standard of practice (SoP) and the impact of universal immunoprophylaxis with nirsevimab was estimated using a static decision-analytic model in a cohort of infants experiencing their first RSV season in the KSA. The model estimated hospital admissions (including pediatric intensive care unit [PICU] admissions and mechanical ventilation [MV]), emergency room (ER) visits, primary care (PC) visits, long-term sequelae, and RSV mortality. RESULTS: The model estimated that under the current SoP, RSV results in 17,179-19,607 hospitalizations (including 2932-3625 PICU and 172-525 MV admissions), 57,654-191,115 ER visits, 219,053-219,970 PC visits, 14 deaths, 12,884-14,705 cases of recurrent wheezing, and a total cost of SAR 480-619 million. Universal nirsevimab immunoprophylaxis was estimated to avert 58% of hospitalizations (58% PICU admissions, 58% MV episodes), 53% of ER visits, 53% of PC visits, 58% of episodes of recurrent wheezing, 8 deaths, and result in savings of SAR 274-343 million in total healthcare cost. CONCLUSION: Compared with current SoP, an nirsevimab immunoprophylaxis strategy in the KSA for all infants during their first RSV season was estimated to dramatically decrease healthcare resource use, and economic burden associated with RSV.


Assuntos
Infecções por Vírus Respiratório Sincicial , Vírus Sinciciais Respiratórios , Lactente , Criança , Humanos , Infecções por Vírus Respiratório Sincicial/epidemiologia , Infecções por Vírus Respiratório Sincicial/prevenção & controle , Antivirais/uso terapêutico , Arábia Saudita/epidemiologia , Sons Respiratórios , Hospitalização
4.
Int J Mol Sci ; 24(24)2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38139208

RESUMO

Herein, we measured the antidiabetic and nephroprotective effects of the sodium-glucose cotransporter-2 inhibitor (empagliflozin; SGLT2i) and synthetic active vitamin D (paricalcitol; Pcal) mono- and co-therapy against diabetic nephropathy (DN). Fifty mice were assigned into negative (NC) and positive (PC) control, SGLT2i, Pcal, and SGLT2i+Pcal groups. Following establishment of DN, SGLT2i (5.1 mg/kg/day) and/or Pcal (0.5 µg/kg/day) were used in the designated groups (5 times/week/day). DN was affirmed in the PC group by hyperglycaemia, dyslipidaemia, polyuria, proteinuria, elevated urine protein/creatinine ratio, and abnormal renal biochemical parameters. Renal SREBP-1 lipogenic molecule, adipokines (leptin/resistin), pro-oxidant (MDA/H2O2), pro-inflammatory (IL1ß/IL6/TNF-α), tissue damage (iNOS/TGF-ß1/NGAL/KIM-1), and apoptosis (TUNEL/Caspase-3) markers also increased in the PC group. In contrast, renal lipolytic (PPARα/PPARγ), adiponectin, antioxidant (GSH/GPx1/SOD1/CAT), and anti-inflammatory (IL10) molecules decreased in the PC group. Both monotherapies increased insulin levels and mitigated hyperglycaemia, dyslipidaemia, renal and urine biochemical profiles alongside renal lipid regulatory molecules, inflammation, and oxidative stress. While SGLT2i monotherapy showed superior effects to Pcal, their combination demonstrated enhanced remedial actions related to metabolic control alongside renal oxidative stress, inflammation, and apoptosis. In conclusion, SGLT2i was better than Pcal monotherapy against DN, and their combination revealed better nephroprotection, plausibly by enhanced glycaemic control with boosted renal antioxidative and anti-inflammatory mechanisms.


Assuntos
Diabetes Mellitus Tipo 2 , Nefropatias Diabéticas , Dislipidemias , Hiperglicemia , Inibidores do Transportador 2 de Sódio-Glicose , Camundongos , Animais , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Controle Glicêmico , Peróxido de Hidrogênio/uso terapêutico , Nefropatias Diabéticas/metabolismo , Inflamação , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Anti-Inflamatórios/uso terapêutico
5.
J Orthod Sci ; 12: 60, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37881678

RESUMO

AIM: To determine the prevalence of malocclusions and the need for orthodontic treatment in a sample of school-going adolescents in the Najran city, Kingdom of Saudi Arabia (KSA). METHODOLOGY: This cross-sectional study was conducted among 1094 school-going Saudi male adolescents. The age range of the sampled adolescents was 13-18 years, and none of them had any history of orthodontic treatment. A survey chart related to malocclusion was designed and filled up after clinical examination by a single experienced and calibrated examiner. The need for orthodontic treatment was assessed using the Index of Orthodontic Treatment Need (IOTN). RESULT: The present study's findings demonstrated 61.2% of the samples with Angle's Class I malocclusions, 27.5% with Class II, and 11.4% of samples with Class III malocclusion. A significant difference was observed between the different classes of malocclusion (P < 0.001). Most samples presented normal overjet, crossbite, and no reverse overjet, deep bite, or open bite. The number of samples with no treatment need was 573 (52.37%), with slight treatment in 185 (16.91%) samples, moderate treatment needs in 123 (11.24%) samples, and severe and extreme treatment needs were 109 (9.96%) and 104 (9.50%), respectively. A significant difference was observed between the samples with no or slight treatment need (grades 1 and 2), moderate need (grade 3), and definite treatment need (grades 4 and 5) (p < 0.001). CONCLUSION: The prevalence of malocclusion and IOTNs among the sample of school-going adolescents in the Najran city was 47.63%. However, 9.63% of those samples required immediate attention for orthodontic treatment.

6.
Cureus ; 15(7): e42563, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37637610

RESUMO

OBJECTIVES: The purpose of this investigation was to evaluate the effects of the COVID-19 pandemic on the respiratory syncytial virus (RSV) prevention program at our institution across three time frames: 2019-2020, 2020-2021, and 2021-2022. METHODS: We carried out a descriptive, single-site observational study spanning four years, from June 2019 to June 2022. Our study included patients in our institution's RSV program who met our enrollment criteria. We collected information about the number of children receiving immunoprophylaxis, immunoprophylaxis doses, and RSV risk factors. RESULTS: The number of patients receiving immunoprophylaxis dropped across the three periods, from 315 patients in the first period (2019-2020) to 176 in the second period (2020-2021), and further decreased to 128 in the third period (2021-2022). Following the COVID-19 pandemic, there was a 50% reduction in the number of patients receiving immunoprophylaxis. The proportion of RSV-infected patients remained relatively similar in the first and second periods (2.86% and 2.27%, respectively) but increased in the third period (5.47%). In the first period, most patients (60.32%) received seven doses, 11.75% got four to six doses, and 27.95% received three doses or fewer. The second period saw 59.66% of patients receiving four to six doses and 40.34% receiving three doses or fewer. In the third period, a mere 9.38% received four to five doses, while 90.63% got three doses or fewer. CONCLUSIONS: While preventative measures associated with COVID-19 may have helped reduce the number of RSV cases, the pandemic seems to have caused a significant decrease in the number of children receiving immunoprophylaxis and the doses of immunoprophylaxis. More extensive, multicenter research is needed to understand the impact of the COVID-19 pandemic on RSV immunoprophylaxis, its activity, and seasonal patterns fully.

7.
Stem Cell Res ; 71: 103158, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37406498

RESUMO

Myoglobin (MB) is a cytoplasmic hemoprotein that is predominantly expressed in the heart and oxidative myofibers of skeletal muscle. It has been demonstrated that MB binds to oxygen and promotes its diffusion for energy production in the mitochondria. Recently, MB was found to be expressed in different forms of malignant tumors and cancer cell lines. Further studies using gene disruption technology will enhance the understanding of MB's role in human cardiovascular biology and cancers. Here, we describe the generation of a homozygous MB knockout in human embryonic stem cells (hESC-MB-/-) via CRISPR/Cas9 to study MB function in human biology and diseases.


Assuntos
Células-Tronco Embrionárias Humanas , Mioglobina , Humanos , Mioglobina/genética , Mioglobina/metabolismo , Células-Tronco Embrionárias Humanas/metabolismo , Sistemas CRISPR-Cas/genética , Linhagem Celular , Tecnologia
8.
Cureus ; 15(5): e39318, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37351252

RESUMO

BACKGROUND: Prostate cancer is a common type of cancer in Saudi Arabia with a high incidence rate. Trans-rectal ultrasound guided prostatic biopsy (TRUSBx) has been the standard diagnostic study for prostate cancer since a landmark study in 1989 which showed that it is better than digitally directed biopsy sampling of the prostate. As an alternative to TRUSBx, transperineal biopsies (TPBx) have gained popularity as they give a higher accuracy rate and avoid many complications. A new study has been conducted in Riyadh, Saudi Arabia to compare TRUSBx and TPBx showed that TPBx has a significantly higher detection rate of prostate cancer cases compared to TRUSBx (45.1% vs. 29.1%, p=0.003). The aim of this study is to determine the diagnostic value and safety of freehand transperineal prostate biopsy in patients with an elevated prostatic specific antigen (PSA) and/or abnormal digital rectal exam in King Fahad Specialist Hospital KFSH in Buraydah, Qassim region, Saudi Arabia. METHODS: This is an observational retrospective study of all patients (n=39) who underwent transperineal biopsies at KFSH to assess the diagnostic value and safety of the procedure. RESULTS: The mean age of the patients was 70.3 (SD 10.1) years. The most commonly found diagnosis was adenocarcinoma (61.5%), and incidence of complications was detected in (5.1%) of the patients. CONCLUSION: We concluded that the freehand technique TPBx has a high accuracy rate in detecting prostatic cancer. However, the learning curve could be a limiting factor in implementing it. Increasing the number of biopsies could positively affect diagnostic accuracy, especially with our low complication rate in this procedure. A low number of biopsies in the older age group can give an accurate result with a low risk of complications. Although template-guided TPBx and robot-guided TPBx are better options, the freehand technique represents a cost-effective and time-saving alternative. However, more studies are needed to compare the outcome of such a technique.

9.
Plast Reconstr Surg Glob Open ; 11(3): e4827, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36875926

RESUMO

Cutaneous angiosarcomas are rare, aggressive tumors with high recurrence and poor prognosis. We share our experiences with the challenging surgical management of these lesions, focusing on both ablative and reconstructive outcomes. Methods: Retrospective cross-sectional chart review was conducted of patients diagnosed with scalp cutaneous angiosarcoma between 2005 and 2021. Resectability, defect reconstruction, and survival outcomes were analyzed. Results: Thirty patients were included, 27 (90%) men and three (10%) women, with a mean age at diagnosis of 71.77 ± 7.3 years, and mean follow-up of 429.43 ± 305.6 days. Only 12 patients completed their regular follow-up, while the remaining patients died. There was a median survival of 443.50 days (range, 42-1283) and median time to recurrence of 21 days (range, 30-1690). Multimodal therapy compared with surgery alone had a significantly better overall median survival (468 days versus 71 days; P = 0.021). Defect coverage was obtained in 24 cases (75%) through an anterolateral thigh flap, two patients (6%) with a local transposition flap, and one patient (3%) with a transverse rectus abdominis myocutaneous flap. The remaining three patients received a skin graft. All of the flaps survived, with one requiring a vein graft for venous congestion. Conclusions: Timely multimodal therapy with a histologically safe margin, combined with adjuvant therapy, improves survival and delays recurrence and metastasis, in cutaneous angiosarcoma patients. An anterolateral thigh flap facilitates the coverage of wide defects. Further investigations of advanced treatment modalities such as immunotherapy and/or gene therapy are required to deal with this highly aggressive tumor.

10.
Sensors (Basel) ; 22(23)2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36502144

RESUMO

According to the standard paradigm, white box cryptographic primitives are used to block black box attacks and protect sensitive information. This is performed to safeguard the protected information and keys against black box assaults. An adversary in such a setting is aware of the method and can analyze many system inputs and outputs, but is blind to the specifics of how a critical instantiation primitive is implemented. This is the focus of white-box solutions, which are designed to withstand attacks that come from the execution environment. This is significant because an attacker may obtain unrestricted access to the program's execution in this environment. The purpose of this article is to assess the efficiency of white-box implementations in terms of security. Our contribution is twofold: first, we explore the practical implementations of white-box approaches, and second, we analyze the theoretical foundations upon which these implementations are built. First, a research proposal is crafted that details white-box applications of DES and AES encryption algorithms. To begin, this preparation is necessary. The research effort planned for this project also includes cryptanalysis of these techniques. Once the general cryptanalysis results have been examined, the white-box design approaches will be covered. We have decided to launch an investigation into creating a theoretical model for white box, since no prior formal definitions have been offered, and suggested implementations have not been accompanied by any assurance of security. This is due to the fact that no formal definition of "white box" has ever been provided. In this way lies the explanation for why this is the situation. We define WBC to encompass the security requirements of WBC specified over a white box cryptography technology and a security concept by studying formal models of obfuscation and shown security. This definition is the product of extensive investigation. This state-of-the-art theoretical model provides a setting in which to investigate the security of white-box implementations, leading to a wide range of positive and negative conclusions. As a result, this paper includes the results of a Digital Signature Algorithm (DSA) study which may be put to use in the real world with signature verification. Possible future applications of White Box Cryptography (WBC) research findings are discussed in light of these purposes and areas of investigation.


Assuntos
Algoritmos , Segurança Computacional , Modelos Teóricos
11.
Children (Basel) ; 9(11)2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36421233

RESUMO

Montelukast is a leukotriene receptor antagonist (LTRA) commonly prescribed for asthma, allergic rhinitis and sleep-related breathing disorders. Recently, some studies have reported several adverse events, such as neuropsychiatric disorders and sleep disturbances, among children. OBJECTIVE: To obtain more insight into the safety profile of montelukast for children with asthma, allergic rhinitis and sleep-related breathing disorders. METHOD AND RESULTS: We retrospectively studied all adverse drug reactions to montelukast among 385 children 6 months or older in six tertiary centers over a two-year period. A total of 89.6% were asthmatic, 50% had allergic rhinitis and 13.6% had sleep-related breathing disorders; Singulair was the most common type of montelukast used (67.9%). This study reported a high prevalence of adverse drug reactions among 123 patients (31.9%), predominantly in those aged 4-9 years (52.8%), followed by adolescents (24.4%) and toddlers (22.8%). Two (ADRs) were reported in 9.8% of the children, while three or more were reported in 5.5%. Sleep disturbance was the most common (ADRs), affecting 15.1% of participants (overlap was common; 5.5% of children experienced sleep difficulties, 4.4% experienced sleep interruption and decreased sleep, and 1.82% experienced nightmares), followed by agitation (10.4%), pain (9.4%) and hyperactivity (6.8%). No serious (ADRs) were reported. Eleven percent of families faced difficulties in purchasing montelukast, and only 57% of families had insurance. Misconceptions were common (9.8% reported it to be a steroid, while 30.6% believed it to be a bronchodilator). Although 81% of the families believed it was an effective and preventive medication, 5.3% stopped the drug due to concern about side effects, especially agitation (3%) and nightmares (0.6%). CONCLUSION: These data demonstrate that montelukast is effective, but the associated adverse neuropsychiatric drug reactions are more prevalent than those reported in the literature. In particular, sleep disturbance, agitation, pain and hyperactivity were observed. Pediatricians should be aware of such (ADRs). Misconceptions about montelukast are still common, and parental counseling and urgent epidemiological studies are needed to quantify the risk for management plans.

12.
iScience ; 25(5): 104189, 2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35494225

RESUMO

Discovering loci under balancing selection in humans can identify loci with alleles that affect response to the environment and disease. Genome variation data have identified the 5' region of the DMBT1 gene as undergoing balancing selection in humans. DMBT1 encodes the pattern-recognition glycoprotein DMBT1, also known as SALSA, gp340, or salivary agglutinin. DMBT1 binds to a variety of pathogens through a tandemly arranged scavenger receptor cysteine-rich (SRCR) domain, with the number of domains polymorphic in humans. We show that the signal of balancing selection is driven by one haplotype usually carrying a shorter SRCR repeat and another usually carrying a longer SRCR repeat. DMBT1 encoded by a shorter SRCR repeat allele does not bind a cariogenic and invasive Streptococcus mutans strain, in contrast to the long SRCR allele that shows binding. Our results suggest that balancing selection at DMBT1 is due to host-microbe interactions of encoded SRCR tandem repeat alleles.

13.
Comput Intell Neurosci ; 2022: 1621258, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35498195

RESUMO

A radio communication sensor system is a collection of sensor modules that are connected to one another through wireless communication. It is common for them to be battery-powered and responsive to a nearby controller, referred to as the base station. They are capable of doing basic computations and transferring information to the base station in most scenarios. They are also in charge of transporting data from distant nodes, putting a burden on nodes with limited resources, and contributing to the quick depletion of energy in these nodes in the process. Nodes in close proximity to the base station are responsible for more than only detecting and sending data to the base station; they are also responsible for transmitting data from faraway nodes. To reward nodes that perform well, a protocol known as the Improved Fuzzy Inspired Energy Effective Protocol (IFIEEP) employs three separate sorts of nodes in order to provide more energy to those who do not. It takes into account the remaining node energy, the node's proximity to the base station, the node's neighbor concentration, and the node's centrality in a cluster when determining node viability. All of these assumptions are founded on a shaky understanding of the situation. Adaptive clustering must be applied to the most viable nodes in order to identify cluster leaders and transmit data to the base station, in addition to disseminating data across the rest of the network, in order to achieve success. In addition, the research provides proper heterogeneity parameters, which describe, among other things, the number of nodes as well as the starting energy of each node. The percentage gain in-network lifetime when compared to current approaches is minor for smaller numbers of supernodes; however, the percentage gain in the area covered 12.89 percent and 100% when more significant numbers of super nodes are used. These improvements in stability, residual energy, and throughput are accomplished by combining these improvements while also taking into consideration the previously neglected energy-intensive sensing energy aspect. The protocol that has been presented is meant to be used in conjunction with applications that make use of blockchain technology.


Assuntos
Blockchain , Aprendizado Profundo , Comunicação , Atenção à Saúde , Tecnologia
14.
Saudi Med J ; 43(4): 329-340, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35414610

RESUMO

In Saudi Arabia, the prevalence of pediatric asthma ranges between 8% and 25%. However, there are no sufficient data regarding severe asthma in childhood in Saudi Arabia. Therefore, a task force has been formed by the Saudi Pediatric Pulmonology Association which is a subsidiary group of the Saudi Thoracic Society and consists of Saudi experts with well-respected academic and clinical backgrounds in the fields of pediatric asthma as well as other respiratory diseases to write a consensus on definitions, phenotypes, and pathophysiology, evaluation, and management. To achieve this, the subject was divided into various sections, each of which was assigned to at least 2 experts. Without a central literature review, the authors searched the literature using their own strategies. To reach an agreement, the entire panel reviewed and voted on proposed findings and recommendations.


Assuntos
Asma , Pneumologia , Comitês Consultivos , Asma/diagnóstico , Asma/epidemiologia , Asma/etiologia , Criança , Humanos , Prevalência , Arábia Saudita/epidemiologia
15.
Comput Intell Neurosci ; 2022: 1912603, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35178075

RESUMO

In the modern world, the security of the digital image is vital due to the frequent communication of digital products over the open network. Accelerated advancement of digital data exchange, the importance of information security in the transmission of data, and its storage has emerged. Multiple uses of the images in the security agencies and the industries and the security of the confidential image data from unauthorized access are emergent and vital. In this paper, Bose Chaudhary Hocquenghem (BCH) codes over the Galois field are used for image encryption. The BCH codes over the Galois field construct MDS (maximum distance separable) matrices and secret keys for image encryption techniques. The encrypted image is calculated, by contrast, correlation, energy, homogeneity, and entropy. Histogram analysis of the encrypted image is also assured in this paper. The proposed image encryption scheme's security analysis results are improved compared to the original AES algorithm. Further, security agencies can utilize this work for their confidential image data.


Assuntos
Segurança Computacional , Processamento de Imagem Assistida por Computador , Algoritmos , Comunicação , Entropia , Processamento de Imagem Assistida por Computador/métodos
16.
Biochimie ; 192: 102-110, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34655671

RESUMO

Hydroxyl radicals (OH.) are one of the most active reactive oxidants recognized for their deleterious effects to cause protein oxidative damage. Thymoquinone, a monoterpene molecule abundantly present in black cumin and known for its pharmacological activities, but its activity against the OH.-induced protein oxidative damage has never been explored. This study determined the therapeutic potential of thymoquinone against OH.-induced oxidative human hemoglobin damage. Novel data demonstrated that thymoquinone provides structural protection of hemoglobin against oxidative damage. Treatment of hemoglobin with OH. induces hypochromicity at 280 and 405 nm, whereas thymoquinone reversed these hypochromic effects. In addition, OH. cause significant reduction in tryptophan fluorescence, however thymoquinone also reversed these damaging effects. Thymoquinone also reduces OH.-induced hydrophobicity and also reduces OH.-induced carbonylation. Moreover, it also inhibits thermal stabilization of OH.-hemoglobin complex. SDS-PAGE of unmodified hemoglobin showed four bands, which disappeared upon OH. treatment and these changes were also retained by thymoquinone. In conclusion, this is the first study that shows the therapeutic potential of thymoquinone against OH.-induced oxidative damage in human hemoglobin.


Assuntos
Benzoquinonas/química , Hemoglobinas/química , Carbonilação Proteica , Humanos , Oxirredução
17.
Sensors (Basel) ; 21(21)2021 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-34770346

RESUMO

Signcryption schemes leveraging chaotic constructions have garnered significant research interest in recent years. These schemes have proffered practical solutions towards addressing the vast security vulnerabilities in Electronic Cash Systems (ECS). The schemes can seamlessly perform message confidentiality and authentication simultaneously. Still, their applications in emerging electronic cash platforms require a higher degree of complexity in design and robustness, especially as billions of online transactions are conducted globally. Consequently, several security issues arise from using open wireless channels for online business transactions. In order to guarantee the security of user information over these safety-limited channels, sophisticated security schemes are solely desired. However, the existing signcryption schemes cannot provide the required confidentiality and authentication for user information on these online platforms. Therefore, the need for certificateless group signcryption schemes (CGSS) becomes imperative. This paper presents an efficient electronic cash system based on CGSS using conformable chaotic maps (CCM). In our design, any group signcrypter would encrypt information/data with the group manager (GM) and send it to the verifier, who confirms the authenticity of the signcrypted information/data using the public criteria of the group. Additionally, the traceability, unforgeability, unlinkability, and robust security of the proposed CGSS-CCM ECS scheme have been built leveraging computationally difficult problems. Performance evaluation of the proposed CGSS-CCM ECS scheme shows that it is secure from the Indistinguishably Chosen Ciphertext Attack. Finally, the security analysis of the proposed technique shows high efficiency in security-vulnerable applications. Overall, the scheme gave superior security features compared to the existing methods in the preliminaries.


Assuntos
Segurança Computacional , Telemedicina , Algoritmos , Confidencialidade , Eletrônica
18.
Sensors (Basel) ; 21(21)2021 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-34770535

RESUMO

The place of public key cryptography (PKC) in guaranteeing the security of wireless networks under human-centered IoT environments cannot be overemphasized. PKC uses the idea of paired keys that are mathematically dependent but independent in practice. In PKC, each communicating party needs the public key and the authorized digital certificate of the other party to achieve encryption and decryption. In this circumstance, a directory is required to store the public keys of the participating parties. However, the design of such a directory can be cost-prohibitive and time-consuming. Recently, identity-based encryption (IBE) schemes have been introduced to address the vast limitations of PKC schemes. In a typical IBE system, a third-party server can distribute the public credentials to all parties involved in the system. Thus, the private key can be harvested from the arbitrary public key. As a result, the sender could use the public key of the receiver to encrypt the message, and the receiver could use the extracted private key to decrypt the message. In order to improve systems security, new IBE schemes are solely desired. However, the complexity and cost of designing an entirely new IBE technique remain. In order to address this problem, this paper presents a provably secure IBE transformation model for PKC using conformable Chebyshev chaotic maps under the human-centered IoT environment. In particular, we offer a robust and secure IBE transformation model and provide extensive performance analysis and security proofs of the model. Finally, we demonstrate the superiority of the proposed IBE transformation model over the existing IBE schemes. Overall, results indicate that the proposed scheme posed excellent security capabilities compared to the preliminary IBE-based schemes.


Assuntos
Segurança Computacional , Confidencialidade , Algoritmos , Computadores , Humanos
20.
Sensors (Basel) ; 21(15)2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34372466

RESUMO

In a channel shared by several nodes, the scheduling algorithm is a key factor to avoiding collisions in the random access-based approach. Commonly, scheduling algorithms can be used to enhance network performance to meet certain requirements. Therefore, in this paper we propose a Delay-Aware Media Access Control (DAMAC) protocol for monitoring time-sensitive applications over multi-hop in Underwater Acoustic Sensor Networks (UASNs), which relies on the random access-based approach where each node uses Carrier Sense Multiple Access/Collision Avoidance (CSMA/CA) to determine channel status, switches nodes on and off to conserve energy, and allows concurrent transmissions to improve the underwater communication in the UASNs. In addition, DAMAC does not require any handshaking packets prior to data transmission, which helps to improve network performance in several metrics. The proposed protocol considers the long propagation delay to allow concurrent transmissions, meaning nodes are scheduled to transmit their data packets concurrently to exploit the long propagation delay between underwater nodes. The simulation results show that DAMAC protocol outperforms Aloha, BroadcastMAC, RMAC, Tu-MAC, and OPMAC protocols under varying network loads in terms of energy efficiency, communication overhead, and fairness of the network by up to 65%, 45%, and 726%, respectively.

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