41 research outputs found
Further investigation of the effects of 5-hydroxytryptamine, 8-OH-DPAT and DOI to mediate contraction and relaxation responses in the intestine and emesis in Suncus murinus
Role of Dietary Crocin in In Vivo Melanoma Tumor Remission
Background:
Melanoma is a deadly form of malignancy. Early diagnosis might pave the way to cure but its aggressive nature leads to rapid dissemination and colonization of distant organs. Dietary herbs may play a significant role in prevention of cancer. In this study, we tested anti-tumor efficacy of the Crocus sativus derived active constituent crocin, it is well established to have anti-cancer properties in different cancer models by our group and other groups. Notably, crocin is reported to exert anti-proliferative effect on melanoma cells (B16F10) in vitro. However, roles of crocin on in vivo melanoma tumor remission have not yet been reported to our knowledge. Materials and Methods: Melanoma tumor model was established by transplanting B16F10 (5 X 105) cells into C57BL/6 mice, which were then observed for tumor development and once the tumor volume reached 6 mm, mice were divided into (Group I: tumor-bearing animals treated with normal saline and Group II: counterparts treated with crocin at 2 mg/kg body weight for 21 days). . Tumor remission and tumor growth related parameters such as tumor silent period (TSP), tumor volume doubling time (VDT), growth delay (GD), and mean survival time (MST) were determined. In addition, serum protein profiles were analyzed. Results: The 21 days crocin treatment significantly reduced the tumor burden in mice, extending the mean survival time significantly as compared to control. Crocin treatment also significantly increased the TGD and TSP and decreased VDT. Furthermore, while serum proteins such as albumin and globulin (alpha1, alpha2, beta, and gamma) were altered due to tumor burden, crocin treatment resulted in their levels near to normal at the end of the experimental period. Conclusion: Our study provided clear evidence that crocin may exhibit significant melanoma tumor remission properties by positively modulating tumor growth related parameters. In future, the molecular mechanisms of crocin action should be studied extensively in melanoma models before defining crocin-based melanoma drug formulation
Breast cancer receptor status assessment and clinicopathological association in Nigerian women: A retrospective analysis
Background: Breast cancer markers are becoming increasingly important in breast cancer research due to their impact on prognosis, treatment and survival. The present retrospective study was carried out to quantify the proportion of estrogen (ER), progesterone (PR), and human epithelial receptor 2 (HER2) expressions and their association with tumour grade, age, and tumour size in breast cancer patients in Nigeria. Materials and methods: The paraffin embedded tissue sections were analysed for breast cancer markers using monoclonal antibody SP1 for ER and SP2 for PR and polyclonal antibody ErbB2 for HER2. Results: A total of 286 breast cancer paraffin wax tissue sections were analysed for ER, PR and HER2 expression. Of all the tissue samples examined, 20 (7%) were ER-positive, 6 (2.1%) were PR-positive, 11 (3.8%) were HER2-positive whereas 248 (87%) were triple-negative breast carcinoma. ER- and PR-positivity was associated with early grade I and II tumours (P 50mm (P < 0.0001). Conclusion: A small proportion of Nigerian women with breast cancer are ER/PR-positive which are associated with less aggressive, better prognosis and benefit from endocrine therapy. An even smaller proportion of patients with aggressive tumors were HER2-posivite but responsive to Herceptin treatment. Unfortunately, a very high proportion of cases were triple-negative which is associated with very aggressive tumours and no targeted treatment, which may explain the high mortality rates from breast cancer in Nigeri
Characterization and Biocompatibility Study of Nematic and Cholesteryl Liquid Crystals.
noIntensive research in bio-engineering has been conducted in the search for flexible biomaterials that could support cell growth and cells attachment. Flexible synthetic materials that support cell growth without the aid of synthetic extracellular matrix proteins are still rare. Cholesteryl liquid crystal containing cholesteryl moieties may have suitable biological affinity. Human keratinocytes (HaCat) were cultured with a nematic liquid crystal and three cholesteryl liquid crystals of different formulation. Subsequently, the trypan blue dye exclusion assay was used to determine cell viability in the liquid crystals. The two classes of liquid crystal were characterized by Differential Scanning Calorimeter (DSC) and polarizing microscope (POM) to understand the nature of the interface material. The cell viability study in medium containing liquid crystals verified that liquid crystals had no effects on cell viability. However, only the surface of cholesteryl liquid crystal has shown affinity to HaCat cells. In addition, cells continued to proliferate in the presence of liquid crystals without a change of medium for eight days. No sign of exothermic and endothermic activities at 370C were observed from the DSC test results for the three samples. Biological and mechanical test result of the cholesteryl liquid crystals has shown that cholesteryl liquid crystals are non toxic and support cell attachment without extracellular matrix protein at very low elasticity
Intestinal model of Inflammation in primary cells
The gastrointestinal tract contains an enormous mucosal surface, which is continuously exposed
to antigens hence making it susceptible to an inflammatory response. Such response targets
potential pathogens by direct activation of the mucosal immune cells, however, in newborns the
continuous inflammation attacks the intestine which leads to induction of necrotising
enterocolitis. The present study aims at developing an “in-vitro” intestinal model of inflammation to assist in understanding the complex interplay of pro-inflammatory mediators during the immune response in neonates. Segments (1.5cm length) from the ileum were obtained from SD rat neonates (1-4 days old) and exposed to 0.25% trypsin/EDTA for 30min. Following trituration and subsequent centrifugation for 5min at 450xg, cells were suspended in DMEM-Hepes
supplemented with 10% FCS, 2.5% Penicillin/Streptomycin, 2.5% L-Glutamine, and 0.2% Amphotericin B. Cell suspension were transferred to culture flaks and incubated at 37°C. Once confluent, the cell preparation media was replaced by FCS-free media, and treated with 0, 10, 50, and 100'g/ml of LPS. IL-8 and nitric oxide (NO) response were subsequently measured. In
separate studies cell proliferation, cell viability, and cell adhesion were analysed. Additionally, the phenotypic properties of the intestinal muscle cells were also investigated via
immunocytochemistry. Initial studies demonstrated that LPS treatments induced a significant
increase in the release of IL-8 and NO compared to controls. The effect of LPS treatments on cell
dynamics demonstrated small changes in cell viability and adhesion, whereas an increase in cell proliferation was observed. Immunocytochemistry studies indicated that LPS treatment caused a decrease in the expression of actin fibers with impaired distribution compared to controls. In the present model key aspects of intestinal inflammation were replicated “in-vitro” including the activation of pro-inflammatory mediators, the loss in enteric innervations and subsequent tissue hyperplasia. Thus, this model may be used as a tool to investigate the anti-inflammatory properties of candidate drugs targeting functional GI diseases
COVID-19 and diabetes in 2020: a systematic review
Attempts were made to review the literature on diabetic patients who experience complications when they contract
COVID-19, and to determine whether ethnicity and other risk factors play an important role in the development of
symptoms and their severity, as well as responding to medications. A literature search was performed using fve keywords, namely COVID-19, diabetes, ethnicity, medications, and risk factors between January 2019 and December 2020
using electronic databases such as PubMed, Science Direct, Google Scholar, Springer Link, and Scopus. Forty studies
were included. The review indicated that diabetes was a signifcant risk factor for poorer outcomes and increased
mortality associated with COVID-19. There were several risk factors for diabetic patients that increased their likelihood
of poorer outcomes associated with COVID-19. These included black and Asian ethnicity, male sex with high BMI. In
conclusion, patients with diabetes of black or Asian origin with high BMI, male sex, and older age had an increased
risk of poorer outcomes associated with COVID-19. This highlights the importance of considering the history of the
patient in prioritising care and treatment
Expanding the Chemical Space of Withaferin A by Incorporating Silicon to Improve its Clinical Potential on Human Ovarian Carcinoma Cells
Ovarian
cancer represents the seventh most commonly diagnosed cancer
worldwide. Herein, we report on the development of a withaferin A
(WA)-silyl ether library with 30 analogues reported for the first
time. Cytotoxicity assays on human epithelial ovarian carcinoma cisplatin-sensitive
and -resistant cell lines identified eight analogues displaying nanomolar
potency (IC50 ranging from 1 to 32 nM), higher than that
of the lead compound and reference drug. This cytotoxic potency is
also coupled with a good selectivity index on a nontumoral cell line.
Cell cycle analysis of two potent analogues revealed cell death by
apoptosis without indication of cell cycle arrest in G0/G1 phase.
The structure–activity relationship and in silico absorption,
distribution, metabolism, and excretion studies demonstrated that
the incorporation of silicon and a carbonyl group at C-4 in the WA
framework enhances potency, selectivity, and drug likeness. These
findings reveal analogues 22, 23, and 25 as potential candidates for clinical translation in patients
with relapsed ovarian cancer
Cannabinoid pharmacology in cancer research: A new hope for cancer patients?
Cannabinoids have been used for many centuries to ease pain and in the past decade, the endocannabinoid system has been implicated in a number of pathophysiological conditions, such as mood and anxiety disorders, movement disorders such as Parkinson's and Huntington's disease, neuropathic pain, multiple sclerosis, spinal cord injury, atherosclerosis, myocardial infarction, stroke, hypertension, glaucoma, obesity, and osteoporosis. Several studies have demonstrated that cannabinoids also have anti-cancer activity and as cannabinoids are usually well tolerated and do not produce the typical toxic effects of conventional chemotherapies, there is considerable merit in the development of cannabinoids as potential anticancer therapies. Whilst the presence of psychoactive effects of cannabinoids could prevent any progress in this field, recent studies have shown the value of the non-psychoactive components of cannabinoids in activating apoptotic pathways, inducing anti-proliferative and anti-angiogenic effects. The aforementioned effects are suggested to be through pathways such as ERK, Akt, mitogen-activated protein kinase (MAPK) pathways, phosphoinositide 3-kinase (PI3K) pathways and hypoxia inducible factor 1 (HIF1), all of which are important contributors to the hallmarks of cancer. Many important questions still remain unanswered or are poorly addressed thus necessitating further research at basic pre-clinical and clinical levels. In this review, we address these issues with a view to identifying the key challenges that future research needs to address
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Global burden of 288 causes of death and life expectancy decomposition in 204 countries and territories and 811 subnational locations, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021
BACKGROUND Regular, detailed reporting on population health by underlying cause of death is fundamental for public health decision making. Cause-specific estimates of mortality and the subsequent effects on life expectancy worldwide are valuable metrics to gauge progress in reducing mortality rates. These estimates are particularly important following large-scale mortality spikes, such as the COVID-19 pandemic. When systematically analysed, mortality rates and life expectancy allow comparisons of the consequences of causes of death globally and over time, providing a nuanced understanding of the effect of these causes on global populations. METHODS The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 cause-of-death analysis estimated mortality and years of life lost (YLLs) from 288 causes of death by age-sex-location-year in 204 countries and territories and 811 subnational locations for each year from 1990 until 2021. The analysis used 56 604 data sources, including data from vital registration and verbal autopsy as well as surveys, censuses, surveillance systems, and cancer registries, among others. As with previous GBD rounds, cause-specific death rates for most causes were estimated using the Cause of Death Ensemble model-a modelling tool developed for GBD to assess the out-of-sample predictive validity of different statistical models and covariate permutations and combine those results to produce cause-specific mortality estimates-with alternative strategies adapted to model causes with insufficient data, substantial changes in reporting over the study period, or unusual epidemiology. YLLs were computed as the product of the number of deaths for each cause-age-sex-location-year and the standard life expectancy at each age. As part of the modelling process, uncertainty intervals (UIs) were generated using the 2·5th and 97·5th percentiles from a 1000-draw distribution for each metric. We decomposed life expectancy by cause of death, location, and year to show cause-specific effects on life expectancy from 1990 to 2021. We also used the coefficient of variation and the fraction of population affected by 90% of deaths to highlight concentrations of mortality. Findings are reported in counts and age-standardised rates. Methodological improvements for cause-of-death estimates in GBD 2021 include the expansion of under-5-years age group to include four new age groups, enhanced methods to account for stochastic variation of sparse data, and the inclusion of COVID-19 and other pandemic-related mortality-which includes excess mortality associated with the pandemic, excluding COVID-19, lower respiratory infections, measles, malaria, and pertussis. For this analysis, 199 new country-years of vital registration cause-of-death data, 5 country-years of surveillance data, 21 country-years of verbal autopsy data, and 94 country-years of other data types were added to those used in previous GBD rounds. FINDINGS The leading causes of age-standardised deaths globally were the same in 2019 as they were in 1990; in descending order, these were, ischaemic heart disease, stroke, chronic obstructive pulmonary disease, and lower respiratory infections. In 2021, however, COVID-19 replaced stroke as the second-leading age-standardised cause of death, with 94·0 deaths (95% UI 89·2-100·0) per 100 000 population. The COVID-19 pandemic shifted the rankings of the leading five causes, lowering stroke to the third-leading and chronic obstructive pulmonary disease to the fourth-leading position. In 2021, the highest age-standardised death rates from COVID-19 occurred in sub-Saharan Africa (271·0 deaths [250·1-290·7] per 100 000 population) and Latin America and the Caribbean (195·4 deaths [182·1-211·4] per 100 000 population). The lowest age-standardised death rates from COVID-19 were in the high-income super-region (48·1 deaths [47·4-48·8] per 100 000 population) and southeast Asia, east Asia, and Oceania (23·2 deaths [16·3-37·2] per 100 000 population). Globally, life expectancy steadily improved between 1990 and 2019 for 18 of the 22 investigated causes. Decomposition of global and regional life expectancy showed the positive effect that reductions in deaths from enteric infections, lower respiratory infections, stroke, and neonatal deaths, among others have contributed to improved survival over the study period. However, a net reduction of 1·6 years occurred in global life expectancy between 2019 and 2021, primarily due to increased death rates from COVID-19 and other pandemic-related mortality. Life expectancy was highly variable between super-regions over the study period, with southeast Asia, east Asia, and Oceania gaining 8·3 years (6·7-9·9) overall, while having the smallest reduction in life expectancy due to COVID-19 (0·4 years). The largest reduction in life expectancy due to COVID-19 occurred in Latin America and the Caribbean (3·6 years). Additionally, 53 of the 288 causes of death were highly concentrated in locations with less than 50% of the global population as of 2021, and these causes of death became progressively more concentrated since 1990, when only 44 causes showed this pattern. The concentration phenomenon is discussed heuristically with respect to enteric and lower respiratory infections, malaria, HIV/AIDS, neonatal disorders, tuberculosis, and measles. INTERPRETATION Long-standing gains in life expectancy and reductions in many of the leading causes of death have been disrupted by the COVID-19 pandemic, the adverse effects of which were spread unevenly among populations. Despite the pandemic, there has been continued progress in combatting several notable causes of death, leading to improved global life expectancy over the study period. Each of the seven GBD super-regions showed an overall improvement from 1990 and 2021, obscuring the negative effect in the years of the pandemic. Additionally, our findings regarding regional variation in causes of death driving increases in life expectancy hold clear policy utility. Analyses of shifting mortality trends reveal that several causes, once widespread globally, are now increasingly concentrated geographically. These changes in mortality concentration, alongside further investigation of changing risks, interventions, and relevant policy, present an important opportunity to deepen our understanding of mortality-reduction strategies. Examining patterns in mortality concentration might reveal areas where successful public health interventions have been implemented. Translating these successes to locations where certain causes of death remain entrenched can inform policies that work to improve life expectancy for people everywhere. FUNDING Bill & Melinda Gates Foundation