25 research outputs found

    The New Dagum-X Family of Distributions: Properties and Applications

    Get PDF
    Various statistical distributions are still being used extensively over the previous decades for modeling data in numerous areas such as engineering, sciences, and finance. Nonetheless, in a lot of applied areas, there is a continuous need for expanded forms of these distributions. However, many common distributions do not fit the data well. Thus, new distributions have been constructed in literature. The purpose of this article is to present a new family of distributions using the Dagum distribution as a generator and to study its properties such as hazard rate functions, moments, quantile function, ordered statistics and Renyi entropy. Moreover, one sub model called Dagum-Frechet distribution is discussed with some of its properties. The maximum likelihood estimation is employed to estimate the parameters of the proposed distribution, and the confidence intervals are obtained. Finally, two real data sets are analyzed to illustrate the performance of the purposed distribution

    Statistical Inference for the Transformed Rayleigh Lomax Distribution with Progressive Type-II Right Censorship

    Get PDF
    In this paper, we study the transformed Rayleigh Lomax (Trans-RL) distribution which belongs to a certain family of two parameters lifetime distributions given by Wang et al (2010). Confidence intervals and inverse estimators of the Trans-RL parameters are derived in terms of order statistics. A simulation study is conducted to report the coverage probabilities, the average biases and the average relative mean square errors for the maximum likelihood, L-moments and inverse estimators. We compare the performance of these methods under different schemes of progressively Type-II right censoring. Finally, an illustrative example is provided to demonstrate the proposed methods

    High insulin resistance in saudi women with unexplained recurrent pregnancy loss: A case–control study

    No full text
    Background: Unexplained recurrent pregnancy loss (RPL) accounts for >50% of the patients with RPL. Insulin resistance (IR) is a potential cause of unexplained RPL. Objectives: To evaluate the relationship between insulin resistance (IR) and unexplained RPL among Saudi women. Methods: This is a single-center, case–control study conducted at a tertiary hospital in the Eastern Province of Saudi Arabia. The study group comprised Saudi women with unexplained RPL, while the control group had Saudi women with at least one live birth and no RPL. Blood samples were taken to determine the fasting glucose (FG) and fasting insulin (FI) levels. Women with diabetes mellitus and polycystic ovarian syndrome were excluded. A homeostatic model assessment of insulin resistance index (HOMA-IR) value ≥3 was considered as IR. Results: The study and control groups comprised 43 and 56 women, respectively. Between the groups, there was a significant difference in the mean age (case: 37.9 ± 5.4 years; control: 32.2 ± 5.9 years; P ˂ 0.0001) and the mean BMI (case: 31.5 ± 6.0; control: 26.1 ± 2.8; P ˂ 0.0001). FG level was slightly higher in the control group (90.9 mg/dL vs 88.7 mg/dL; P = 0.068). FI level was significantly higher in the study group (16.33 μU/mL vs. 6.17 μU/mL; P ˂ 0.0001). HOMA-IR of ≥3 was significantly more common in the study group (n = 22; 51.2%) than the control group (4; 7.1%) (P < 0.0001). After adjusting for age and BMI, IR ≥3 was found to be independently associated with unexplained RPL (aOR: 13.2; 95% CI: 3.77–46.36). Conclusions: This study showed that Saudi women with unexplained RPL had significantly higher levels of fasting insulin and insulin resistance than those without a history of RPL. Therefore, it is recommended to assess IR in women with RPL

    Local Oxygen-Based Therapy (blue<sup>®</sup>m) for Treatment of Peri-Implant Disease: Clinical Case Presentation and Review of Literature about Conventional Local Adjunct Therapies

    No full text
    Peri-implant diseases including peri-implant mucositis and peri-implantitis are among the major causes of failure of implant-supported dental restorations. They are characterized by progressive inflammation of the peri-implant mucosa, extending to the surrounding connective tissues and leading to bone loss and implant failure. Although strict oral hygiene practices help in preventing peri-implant diseases, plaque buildup around the implant restoration leads to chronic inflammation, due to the adherent bacterial biofilm. While mechanical debridement and non-surgical therapy to remove inflamed connective tissue (ICT) form the mainstay of treatment, additional local adjunctive therapies enhance clinical outcomes. Topical oxygen therapy is known to reduce inflammation, increase vascularity, and act as a bacteriostatic measure. The use of oxygen-based therapy (blue®m) products as a local adjunctive therapy for peri-implant mucositis and peri-implantitis can result in clinical outcomes similar to that of conventional local adjuncts such as chlorhexidine, antibiotics, and antibacterial agents. This report aims to present the clinical findings of patients with peri-implant mucositis and peri-implantitis, who were managed using local oxygen-based therapy as an adjunct to non-surgical therapy. In addition, a review of the literature about commonly used local adjuncts for peri-implant diseases has been included in the report to provide a means of comparison between conventional local adjunct therapy and topical oxygen-based therapy. Based on the reported findings and reviewed literature, local oxygen-based adjunct therapy was equally effective as conventionally used local adjuncts such as antibiotics, antibacterials, and probiotics, in treating patients with peri-implant diseases

    Effectiveness of Topical Oxygen Therapy in Gingivitis and Periodontitis: Clinical Case Reports and Review of the Literature

    No full text
    Gingivitis and periodontitis are common oral pathological conditions. Several optional adjunctive local therapies are used clinically. While antibiotics and chlorhexidine are the most common agents of choice, their long-term use is associated with several adverse effects. Some of these include staining of teeth and restorations, cellular cytotoxicity and hypersensitivity. Topical oxygen therapy has been recently introduced and could be clinically capable of inhibiting plaque bacterial biofilm growth. Available as a mouthwash, toothpaste and oral gel, this formulation comprises cellulose, glycerol and sodium peroxoborate, and releases topical oxygen in a controlled manner. Moreover, it releases topical oxygen, in a controlled manner, and lactoferrin, which are capable of antibacterial action and stimulation of bone cells, respectively. The aim of this paper is to report a case of gingivitis and another case of periodontitis, both of which were successfully treated clinically with adjunctive local oxygen therapy (blue®m). Additionally, this paper aims to review the relevant literature in terms of adjunct topical or local therapies used in the treatment of gingivitis and periodontitis, in order to understand how local therapies are helpful and to know if local oxygen therapy is a suitable clinical alternative

    Angiotensin II Exaggerates SARS-CoV-2 Specific T-Cell Response in Convalescent Individuals following COVID-19

    No full text
    Dysregulation of renin&minus;angiotensin systems during coronavirus disease 2019 (COVID-19) infection worsens the symptoms and contributes to COVID-19 severity and mortality. This study sought to investigate the effect of exogenous angiotensin II (Ang-II) on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-specific T-cells response in recovered COVID-19 patients. Human peripheral blood mononuclear cells (PBMCs) were treated with Ang II and then stimulated with a SARS-CoV-2 peptide pool. T-cell responses were measured using flow cytometry, while enzyme-linked immunosorbent assay (ELISA) and intracellular cytokine staining (ICS) assays determined functional capability and polarization. Additionally, the relative level of protein phosphorylation was measured using a phosphokinase array. Our results showed that Ang II treatment significantly increased the magnitude of SARS-CoV-2-specific T-cell response in stimulated PBMCs with a SARS-CoV-2 peptide pool. Moreover, the phosphorylation levels of numerous proteins implicated in cardiovascular diseases, inflammation, and viral infection showed significant increases in the presence of Ang II. The mitogenic stimulation of PBMCs after Ang II and SARS-CoV-2 peptide pool stimulation showed functional polarization of T-cells toward Th1/Th17 and Th17 phenotypes, respectively. Meanwhile, ELISA showed increased productions of IL-1&beta; and IL-6 in Ang II-stimulated PBMCs without affecting the IL-10 level. To our knowledge, this study is the first to demonstrate that Ang II exaggerates SARS-CoV-2-specific T-cells response. Therefore, during COVID-19 infection, Ang II may aggravate the inflammatory response and change the immune response toward a more inflammatory profile against SARS-CoV-2 infection

    The Role of Mitochondrial Dysfunction in Cytotoxic Effects of Solanum nigrum Water Extract on MCF-7 and MDA-MB-231 Breast Cancer Cells

    No full text
    Background: Recent studies suggest that numerous naturally occurring agents have the potential to kill cancer cells via mitochondrial dysfunction. Solanum nigrum is a herb widely used in alternative medical systems. This study aimed to investigate the cytotoxic effect of Solanum nigrum water extract (SNWE) against Michigan Cancer Foundation-7 (MCF-7) and MD Anderson-Metastatic Breast Cancer-231 (MDA-MB-231) cells. Methods: We used an MTT reduction assay for cytotoxicity analysis. To explore the mode of action, the cellular adenosine triphosphate (ATP) levels and mitochondrial membrane potential were analyzed using a colorimetric ATP assay and Rhodamine-123 fluorescent staining, respectively, during SNWE treatment for 72 h. Results: The cytotoxic effect was significant in both cell lines, with IC50 values of 4.26 µg/mL and 5.30 µg/mL in MCF-7 and MDA-MB-231 cells, respectively. The 24, 48, and 72 h treatments of 100 µg/mL SNWE showed 0.85 ± 0.07, 0.38 ± 0.1, and 0.20 ± 0.1 nM ATP in MCF-7 cells and 0.94 ± 0.07, 0.84 ± 0.2 and 0.46 ± 0.2 nM in MDA-MB-231 cells, respectively. The SNWE treatment altered the mitochondrial membrane potential (ΔΨm) in a concentration-dependent manner in both the breast cancer cell lines, to 29.6 ± 4.1% in MCF-7 and 28.7 ± 4.17% in MDA-MB-231 cells, when compared with healthy mitochondria (100% ΔΨm). Conclusions: The cytotoxic effects of Solanum nigrum against breast cancer cells are associated with energy metabolism. Additional studies are warranted to test the anticancer effect of Solanum nigrum using an animal model of breast cancer

    Effect of Osteoporosis on Well-Integrated Bone Implants

    No full text
    The installation of dental implants has become a common treatment for edentulous patients. However, concern exists about the influence of osteoporosis on the final implant success. This study evaluated whether an ovariectomy (OVX)-induced osteoporotic condition, induced eight weeks postimplantation in a rat femoral condyle, influences the bone response to already-integrated implants. The implants were inserted in the femoral condyle of 16 female Wistar rats. Eight weeks postimplantation, rats were randomly ovariectomized (OVX) or sham-operated (SHAM). Fourteen weeks later, animals were sacrificed, and implants were used for histological and histomorphometric analyses. A significant reduction in the quantity and quality of trabecular bone around dental implants existed in OVX rats in comparison to the SHAM group. For histomorphometric analysis, the bone area (BA%) showed a significant difference between OVX (34.2 &plusmn; 4.3) and SHAM (52.6 &plusmn; 12.7) groups (p &lt; 0.05). Bone&ndash;implant contact (BIC%) revealed significantly lower values for all implants in OVX (42.5 &plusmn; 20.4) versus SHAM (59.0 &plusmn; 19.0) rats. Therefore, induction of an osteoporotic condition eight weeks postimplantation in a rat model negatively affects the amount of bone present in close vicinity to bone implants

    Effect of Osteoporosis on Well-Integrated Bone Implants

    No full text
    The installation of dental implants has become a common treatment for edentulous patients. However, concern exists about the influence of osteoporosis on the final implant success. This study evaluated whether an ovariectomy (OVX)-induced osteoporotic condition, induced eight weeks postimplantation in a rat femoral condyle, influences the bone response to already-integrated implants. The implants were inserted in the femoral condyle of 16 female Wistar rats. Eight weeks postimplantation, rats were randomly ovariectomized (OVX) or sham-operated (SHAM). Fourteen weeks later, animals were sacrificed, and implants were used for histological and histomorphometric analyses. A significant reduction in the quantity and quality of trabecular bone around dental implants existed in OVX rats in comparison to the SHAM group. For histomorphometric analysis, the bone area (BA%) showed a significant difference between OVX (34.2 ± 4.3) and SHAM (52.6 ± 12.7) groups (p < 0.05). Bone–implant contact (BIC%) revealed significantly lower values for all implants in OVX (42.5 ± 20.4) versus SHAM (59.0 ± 19.0) rats. Therefore, induction of an osteoporotic condition eight weeks postimplantation in a rat model negatively affects the amount of bone present in close vicinity to bone implants
    corecore