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1.
Heliyon ; 10(12): e32495, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-39021991

RESUMO

It has been realized throughout the years that an ideal combination of high toughness, hardness and strength is required in many engineering applications that need load-bearing capabilities. Ceramics and related materials have significant constraints for structural and particular non-structural applications due to their low toughness and limited strength while having substantially superior hardness than typical metallic materials. For example, hydroxyapatite (HAp) has gained attention for applications in orthopaedic implants, dental materials, drug delivery, etc. Researchers have continued to strive to produce HAp materials with reliable properties within the acceptable Weibull modulus (m) for load bearing. The Weibull analysis (WA) is a statistical analysis adopted widely in reliability applications to detect failure periods. Researchers have confirmed it to be an effective technique to get results on the reliability of materials at a moderately low rate with assured reliability of the material or component. This review summarizes the WA and the steps in the Weibull method for its reliability analysis to predict the failure rate of ceramics like HAp and other related materials. Also, the applications of WA for these materials were reviewed. From the review, it was discovered that Weibull distribution is proven to confer to the feeblest-link concept. For brittle materials, it was revealed that the Weibull Modulus ranges from 2 to 40, and environment, production processes, and comparative factors are well-thought-out contributing factors for reliability. In addition, the confidence interval can be up to 95 %. The frequently used technique for reliability valuation is to syndicate the Weibull statistics. Also, a very narrow distribution is desirable to offer the expected likelihood. Furthermore, when paired with trials, Monte Carlo simulations prove to be a very helpful tool for forecasting the dependability of different estimate techniques and their optimization. Finally, if the equivalent m is anticipated to be high, it signifies that the material has a high degree of homogeneity of properties and high reliability. WA can find application in predicting the dependability and lifetime of materials, making it widely utilized in engineering and other disciplines. It is especially useful for analysing data in which the likelihood of failure per unit of time varies over time.

2.
J Antimicrob Chemother ; 78(8): 2000-2007, 2023 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-37367727

RESUMO

BACKGROUND: Due to the high prevalence of resistance to NNRTI-based ART since 2018, consolidated recommendations from the WHO have indicated dolutegravir as the preferred drug of choice for HIV treatment globally. There is a paucity of resistance outcome data from HIV-1 non-B subtypes circulating across West Africa. AIMS: We characterized the mutational profiles of persons living with HIV from a cross-sectional cohort in North-East Nigeria failing a dolutegravir-based ART regimen. METHODS: WGS of plasma samples collected from 61 HIV-1-infected participants following virological failure of dolutegravir-based ART were sequenced using the Illumina platform. Sequencing was successfully completed for samples from 55 participants. Following quality control, 33 full genomes were analysed from participants with a median age of 40 years and median time on ART of 9 years. HIV-1 subtyping was performed using SNAPPy. RESULTS: Most participants had mutational profiles reflective of exposure to previous first- and second-line ART regimens comprised NRTIs and NNRTIs. More than half of participants had one or more drug resistance-associated mutations (DRMs) affecting susceptibility to NRTIs (17/33; 52%) and NNRTIs (24/33; 73%). Almost a quarter of participants (8/33; 24.4%) had one or more DRMs affecting tenofovir susceptibility. Only one participant, infected with HIV-1 subtype G, had evidence of DRMs affecting dolutegravir susceptibility-this was characterized by the T66A, G118R, E138K and R263K mutations. CONCLUSIONS: This study found a low prevalence of resistance to dolutegravir; the data are therefore supportive of the continual rollout of dolutegravir as the primary first-line regimen for ART-naive participants and the preferred switch to second-line ART across the region. However, population-level, longer-term data collection on dolutegravir outcomes are required to further guide implementation and policy action across the region.


Assuntos
Infecções por HIV , Inibidores de Integrase de HIV , Humanos , Adulto , Estudos Transversais , Infecções por HIV/tratamento farmacológico , Compostos Heterocíclicos com 3 Anéis/uso terapêutico , Compostos Heterocíclicos com 3 Anéis/farmacologia , Oxazinas/uso terapêutico , Piridonas/uso terapêutico , Inibidores de Integrase de HIV/uso terapêutico , Inibidores de Integrase de HIV/farmacologia , Mutação , Farmacorresistência Viral/genética , Integrases/genética
3.
Biology (Basel) ; 10(9)2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34571758

RESUMO

Approximately 15-18% of crops losses occur as a result of animal pests, while weeds and microbial diseases cause 34 and 16% losses, respectively. Fungal pathogens cause about 70-80% losses in yield. The present strategies for plant disease control depend transcendently on agrochemicals that cause negative effects on the environment and humans. Nanotechnology can help by reducing the negative impact of the fungicides, such as enhancing the solubility of low water-soluble fungicides, increasing the shelf-life, and reducing toxicity, in a sustainable and eco-friendly manner. Despite many advantages of the utilization of nanoparticles, very few nanoparticle-based products have so far been produced in commercial quantities for agricultural purposes. The shortage of commercial uses may be associated with many factors, for example, a lack of pest crop host systems usage and the insufficient number of field trials. In some areas, nanotechnology has been advanced, and the best way to be in touch with the advances in nanotechnology in agriculture is to understand the major aspect of the research and to address the scientific gaps in order to facilitate the development which can provide a rationale of different nanoproducts in commercial quantity. In this review, we, therefore, described the properties and synthesis of nanoparticles, their utilization for plant pathogenic fungal disease control (either in the form of (a) nanoparticles alone, that act as a protectant or (b) in the form of a nanocarrier for different fungicides), nano-formulations of agro-nanofungicides, Zataria multiflora, and ginger essential oils to control plant pathogenic fungi, as well as the biosafety and limitations of the nanoparticles applications.

4.
Molecules ; 26(13)2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34202405

RESUMO

The bacterial leaf blight (BLB) caused by Xanthomonas oryzae pv. oryzae (Xoo) is one of the most serious rice diseases, causing huge yield losses worldwide. Several technologies and approaches have been opted to reduce the damage; however, these have had limited success. Recently, scientists have been focusing their efforts on developing efficient and environmentally friendly nanobactericides for controlling bacterial diseases in rice fields. In the present study, a scanning electron microscope (SEM), transmission electron microscope (TEM), and a confocal laser scanning microscope (CLSM) were utilized to investigate the mode of actions of ginger EOs on the cell structure of Xoo. The ginger EOs caused the cells to grow abnormally, resulting in an irregular form with hollow layers, whereas the dimethylsulfoxide (DMSO) treatment showed a typical rod shape for the Xoo cell. Ginger EOs restricted the growth and production of biofilms by reducing the number of biofilms generated as indicated by CLSM. Due to the instability, poor solubility, and durability of ginger EOs, a nanoemulsions approach was used, and a glasshouse trial was performed to assess their efficacy on BLB disease control. The in vitro antibacterial activity of the developed nanobactericides was promising at different concentration (50-125 µL/mL) tested. The efficacy was concentration-dependent. There was significant antibacterial activity recorded at higher concentrations. A glasshouse trial revealed that developed nanobactericides managed to suppress BLB disease severity effectively. Treatment at a concentration of 125 µL/mL was the best based on the suppression of disease severity index, AUDPC value, disease reduction (DR), and protection index (PI). Furthermore, findings on plant growth, physiological features, and yield parameters were significantly enhanced compared to the positive control treatment. In conclusion, the results indicated that ginger essential oils loaded-nanoemulsions are a promising alternative to synthetic antibiotics in suppressing Xoo growth, regulating the BLB disease, and enhancing rice yield under a glasshouse trial.


Assuntos
Óleos Voláteis , Oryza , Doenças das Plantas/microbiologia , Xanthomonas/crescimento & desenvolvimento , Zingiber officinale/química , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Oryza/química , Oryza/crescimento & desenvolvimento , Oryza/microbiologia , Oryza/ultraestrutura , Xanthomonas/ultraestrutura
5.
Support Care Cancer ; 29(2): 679-686, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32430602

RESUMO

Cancer survivors' quality of life (QoL) is consistently shown to be positively impacted by social support from family and friends, including informal caregivers. In contrast, a loved one's negative response to cancer can diminish survivors' QoL, and these negative responses can be more impactful than supportive behaviors. Nonetheless, negative caregiver response has not been extensively researched, and few studies have explored the potential interaction of negative caregiver response and perceived social support on survivors' QoL. Therefore, we examined direct effects of perceived negative caregiver response, and the potential moderating role of social support, on QoL in a population-based sample of cancer survivors (N = 7543) using generalized linear models. Findings indicate that survivors who rated their caregiver's response to their cancer diagnosis more negatively reported worse physical and mental health, even up to 10 years after their initial cancer diagnosis. Perceived social support was not significantly associated with physical health, but it was positively associated with mental health. However, social support was not shown to moderate the relationship between negative caregiver response and mental health. Findings suggest that positive support from others within a survivor's social network may not be enough to attenuate the negative effects of their primary caregiver's unsupportive behaviors. Accordingly, cancer survivorship research and practice must consider the critical role that negative caregiver responses have on survivors' QoL and develop strategies that focus on the survivor-caregiver dynamic.


Assuntos
Sobreviventes de Câncer/psicologia , Cuidadores/psicologia , Neoplasias/psicologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida/psicologia , Apoio Social
6.
J Relig Health ; 58(6): 2196-2207, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31352665

RESUMO

The human papillomavirus (HPV) vaccine is an effective mechanism to prevent HPV-associated cancers; however, uptake is low among women aged 18-26. Religiosity/spirituality is associated with sexual health decision-making. This study examined the role of religious/spiritual beliefs on HPV vaccination among college women (N = 307) using logistic regression and mediation analyses. Findings indicate that sexual activity is the main factor associated with HPV vaccination; and sexual activity fully mediates the relationship between religious/spiritual beliefs and HPV vaccination. Health promotion efforts should highlight the importance of HPV vaccination regardless of current sexual activity and may benefit from partnerships with religious/spiritual organizations.


Assuntos
Infecções por Papillomavirus/prevenção & controle , Vacinas contra Papillomavirus/administração & dosagem , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Religião , Espiritualidade , Estudantes/psicologia , Adolescente , Adulto , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Saúde Sexual , Universidades , Adulto Jovem
7.
Intest Res ; 16(1): 99-108, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29422804

RESUMO

BACKGROUND/AIMS: Colorectal cancer (CRC) is now a major public health problem with heavy morbidity and mortality in rural Africans despite the lingering dietary fiber-rich foodstuffs consumption. Studies have shown that increased intake of dietary fiber which contribute to low fecal pH and also influences the activity of intestinal microbiota, is associated with a lowered risk for CRC. However, whether or not the apparent high dietary fiber consumption by Africans do not longer protects against CRC risk is unknown. This study evaluated dietary fiber intake, fecal fiber components and pH levels in CRC patients. METHODS: Thirty-five subjects (CRC=21, control=14), mean age 45 years were recruited for the study. A truncated food frequency questionnaire and modified Goering and Van Soest procedures were used. RESULTS: We found that all subjects consumed variety of dietary fiber-rich foodstuffs. There is slight preponderance in consumption of dietary fiber by the control group than the CRC patients. We also found a significant difference in the mean fecal neutral detergent fiber, acid detergent fiber, hemicellulose, cellulose and lignin contents from the CRC patients compared to the controls (P<0.05). The CRC patients had significantly more fecal pH level than the matched apparently healthy controls (P=0.017). CONCLUSIONS: The identified differences in the fecal fiber components and stool pH levels between the 2 groups may relate to CRC incidence and mortality in rural Africans. There is crucial need for more hypothesis-driven research with adequate funding on the cumulative preventive role of dietary fiber-rich foodstuffs against colorectal cancer in rural Africans "today."

8.
Indian J Endocrinol Metab ; 16(4): 558-64, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22837916

RESUMO

BACKGROUND: Diabetes Mellitus is the commonest endocrine-metabolic disorder in Nigeria similar to the experience in other parts of the world. The aim was to assess the clinical and laboratory profile, and evaluate the quality of care of Nigerian diabetics with a view to planning improved diabetes care. MATERIALS AND METHODS: In a multicenter study across seven tertiary health centers in Nigeria, the clinical and laboratory parameters of diabetic out-patients were evaluated. Clinical parameters studied include type of diabetes, anthropometry, and blood pressure (BP) status, chronic complications of diabetes, and treatment types. Laboratory data assessed included fasting plasma glucose (FPG), 2-h post-prandial (2-HrPP) glucose, glycated hemoglobin (HbA1c), urinalysis, serum lipids, electrolytes, urea, and creatinine. RESULTS: A total of 531 patients, 209 (39.4%) males and 322 (60.6%) females enrolled. The mean age of the patients was 57.1 ± 12.3 years with the mean duration of diabetes of 8.8 ± 6.6 years. Majority (95.4%) had type 2 diabetes mellitus (DM) compared to type 1 DM (4.6%), with P < 0.001. The mean FPG, 2-HrPP glucose, and HbA1c were 8.1 ± 3.9 mmol/L, 10.6 ± 4.6 mmol/L, and 8.3 ± 2.2%, respectively. Only 170 (32.4%) and 100 (20.4%) patients achieved the ADA and IDF glycemic targets, respectively. Most patients (72.8%) did not practice self-monitoring of blood glucose. Hypertension was found in 322 (60.9%), with mean systolic BP 142.0 ± 23.7 mmHg, and mean diastolic BP 80.7 ± 12.7 mmHg. Diabetic complications found were peripheral neuropathy (59.2%), retinopathy (35.5%), cataracts (25.2%), cerebrovascular disease (4.7%), diabetic foot ulcers (16.0%), and nephropathy (3.2%). CONCLUSION: Most Nigerian diabetics have suboptimal glycemic control, are hypertensives, and have chronic complications of DM. Improved quality of care and treatment to target is recommended to reduce diabetes-related morbidity and mortality.

9.
Psychooncology ; 20(8): 902-5, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20680930

RESUMO

OBJECTIVES: The nature and magnitude of the problems facing caregivers remain largely unknown in developing countries of the world. This study addresses these issues in a group of caregivers of patients with cancer in Zaria, Nigeria. METHOD: One hundred and three patients attending an oncology outpatient clinic at the Ahmadu Bello University Teaching Hospital were enrolled in the study with their caregivers. The caregivers were interviewed using the Socio-demographic data sheet, General Health Questionnaire-30 (GHQ-30) and Zarith Burden Interview (ZBI). A score of 4 or more in GHQ and scores above the median score of the sample in ZBI were considered a clinically significant level of psychological morbidity and a high level of burden, respectively. Data obtained were analyzed using the Statistical Package for Social Sciences Version 13 for Windows. All statistical tests of significance were carried out at 5% level of probability. RESULTS: The patients were 60 women whose mean age was 57. Of the 103 caregivers, 60 (58%) were men and 43 (42%) were women. Their mean age was 37. Their mean ZBI and GHQ-30 scores were 29.16±12.8 (median = 25) and 3.67±3.01, respectively. A high level of burden was found in 49.5% (95% CI 39.9-59.1%) and psychological morbidity was found in 46.6% (95% CI 37.0-56.2%) of the caregivers. High levels of burden and psychological morbidity were significantly associated with absence of financial support. CONCLUSION: The study demonstrated a high level of caregiver burden, psychological morbidity and financial strain in family caregivers coming to the clinic with a relative who has cancer in an urban Nigerian setting.


Assuntos
Cuidadores/psicologia , Efeitos Psicossociais da Doença , Neoplasias/terapia , Escolaridade , Feminino , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Nigéria , Pobreza/psicologia , Fatores Socioeconômicos , Inquéritos e Questionários , População Urbana
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