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Colorectal cancer is one of the most aggressive types of cancer with about two million new cases and one million deaths in 2020. The side effects of the available chemotherapies and the possibility of developing resistance against treatment highlight the importance of developing new therapeutic options. The development in the field of nanotechnology have introduced the application of nanoparticles (NPs) as a promising approach in the diagnosis and treatments of colorectal cancer and other types of cancer. Gold nanoparticles (AuNPs) are currently one of the most studied materials as they possess unique tunable properties allowing them to play a role in colorectal cancer bioimaging, diagnosis, and therapy. The high surface-to-volume ratio of AuNPs mediates their utilization in drug delivery as well as functionalization to provide specific targeting. Moreover, depending on their physical properties (size, shape), AuNPs can be modified to fit the intended application. However, there are contradictory results around the pharmacokinetics of AuNPs including their biodistribution, clearance, and toxicity. This variation of opinions is most likely due to the development of different AuNPs that vary in shape, size, and surface chemistry, in addition to the conditions under which each research was carried out. The conflicting data represent a challenge in the clinical use of AuNPs suggesting the need to understand the toxicity, fate, and long-term exposure of AuNPs in vivo. Thus, there is an unmet need for the establishment of a publicly available data base for extensive analysis. In this review, we discuss the recent advances in AuNP applications in the treatment and diagnosis of colorectal cancer, mechanisms of action, and clinical challenges.
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Neoplasias do Colo , Nanopartículas Metálicas , Humanos , Ouro/química , Ouro/farmacocinética , Ouro/toxicidade , Nanopartículas Metálicas/uso terapêutico , Nanopartículas Metálicas/química , Nanopartículas Metálicas/toxicidade , Distribuição Tecidual , Sistemas de Liberação de Medicamentos , Neoplasias do Colo/diagnóstico , Neoplasias do Colo/tratamento farmacológicoRESUMO
Climate change has a significant impact on the intensity and spread of dengue outbreaks. The objective of this study is to assess the number of dengue transmission suitable days (DTSD) in Pakistan for the baseline (1976-2005) and future (2006-2035, 2041-2070, and 2071-2099) periods under Representative Concentration Pathway (RCP4.5 and RCP8.5) scenarios. Moreover, potential spatiotemporal shift and future hotspots of DTSD due to climate change were also identified. The analysis is based on fourteen CMIP5 models that have been downscaled and bias-corrected with quantile delta mapping technique, which addresses data stationarity constraints while preserving future climate signal. The results show a higher DTSD during the monsoon season in the baseline in the study area except for Sindh (SN) and South Punjab (SP). In future periods, there is a temporal shift (extension) towards pre- and post-monsoon. During the baseline period, the top ten hotspot cities with a higher frequency of DTSD are Karachi, Hyderabad, Sialkot, Jhelum, Lahore, Islamabad, Balakot, Peshawar, Kohat, and Faisalabad. However, as a result of climate change, there is an elevation-dependent shift in DTSD to high-altitude cities, e.g. in the 2020s, Kotli, Muzaffarabad, and Drosh; in the 2050s, Garhi Dopatta, Quetta, and Zhob; and in the 2080s, Chitral and Bunji. Karachi, Islamabad, and Balakot will remain highly vulnerable to dengue outbreaks for all the future periods of the twenty-first century. Our findings also indicate that DTSD would spread across Pakistan, particularly in areas where we have never seen dengue infections previously. The good news is that the DTSD in current hotspot cities is projected to decrease in the future due to climate change. There is also a temporal shift in the region during the post- and pre-monsoon season, which provides suitable breeding conditions for dengue mosquitos due to freshwater; therefore, local authorities need to take adaption and mitigation actions.
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Mudança Climática , Dengue , Animais , Paquistão/epidemiologia , Dengue/epidemiologia , Surtos de Doenças , Estações do AnoRESUMO
Glioblastoma multiforme (GBM) is the most aggressive (WHO grade IV) form of diffuse glioma endowed with tremendous invasive capacity. The availability of narrow therapeutic choices for GBM management adds to the irony, even the post-treatment median survival time is roughly around 14-16 months. Gene mutations seem to be cardinal to GBM formation, owing to involvement of amplified and mutated receptor tyrosine kinase (RTK)-encoding genes, leading to dysregulation of growth factor signaling pathways. Of-late, the role of different microRNAs (miRNAs) in progression and proliferation of GBM was realized, which lead to their burgeon potential applications for diagnostic and therapeutic purposes. miRNA signatures are intricately linked with onset and progression of GBM. Although, progression of GBM causes significant changes in the BBB to form BBTB, but still efficient passage of cancer therapeutics, including antibodies and miRNAs are prevented, leading to low bioavailability. Recent developments in the nanomedicine field provide novel approaches to manage GBM via efficient and brain targeted delivery of miRNAs either alone or as part of cytotoxic pharmaceutical composition, thereby modulating cell signaling in well predicted manner to promise positive therapeutic outcomes.
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Antineoplásicos/administração & dosagem , Sistemas de Liberação de Medicamentos , Glioblastoma/terapia , MicroRNAs/administração & dosagem , Nanomedicina , Nanopartículas/administração & dosagem , Animais , Glioblastoma/genética , Glioblastoma/patologia , Humanos , MicroRNAs/genética , Nanopartículas/químicaRESUMO
Colon cancer is an adenocarcinoma, which subsequently develops into malignant tumors, if not treated properly. The current colon cancer therapy mainly revolves around chemotherapy, radiotherapy and surgery, but the search continues for more effective interventions. With the advancement of nanoparticles (NPs), it is now possible to diagnose and treat colon cancers with different types, shapes, and sizes of NPs. Nanoformulations such as quantum dots, iron oxide, polymeric NPs, dendrimers, polypeptides, gold NPs, silver NPs, platinum NPs, and cerium oxide have been either extensively used alone or in combination with other nanomaterials or drugs in colon cancer diagnosis, and treatments. These nanoformulations possess high biocompatibility and bioavailability, which makes them the most suitable candidates for cancer treatment. The size and shape of NPs are critical to achieving an effective drug delivery in cancer treatment and diagnosis. Most NPs currently are under different testing phases (in vitro, preclinical, and clinical), whereas some of them have been approved for therapeutic applications. We have comprehensively reviewed the recent advances in the applications of NPs-based formulations in colon cancer diagnosis and treatment.
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Antineoplásicos , Neoplasias do Colo , Nanopartículas , Antineoplásicos/uso terapêutico , Neoplasias do Colo/diagnóstico , Neoplasias do Colo/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Ouro , Humanos , PolímerosRESUMO
Epilepsy is a chronic brain disorder, with anti-epileptic drugs (AEDs) providing relief from hyper-excitability of neurons, but largely failing to restrain neurodegeneration. We investigated a progressive preclinical trial in rats, whereby the test drugs; sodium valproate (SVP; 150 and 300 mg/kg), baclofen (BFN; 5 and 10 mg/kg), and thymoquinone (THQ; 40 and 80 mg/kg) were administered (i.p, once/day for 15 days) alone, and as low dose combinations, and subsequently tested for antiseizure and neuroprotective potential using electrical stimulation of neurons by Maximal electroshock (MES). The seizure stages were monitored, and hippocampal levels of m-TOR, IL-1ß, IL-6 were measured. Hippocampal histopathology was also performed. Invitro and Insilco studies were run to counter-confirm the results from rodent studies. We report the synergistic effect of trio-drug combination; SVP (150 mg/kg), BFN (5 mg/kg) and THQ (40 mg/kg) against generalized seizures. The Insilco results revealed that trio-drug combination binds the Akt active site as a supramolecular complex, which could have served as a delivery system that affects the penetration and the binding to the new target. The potential energy of the ternary complex in the Akt active site after dynamics simulation was found to be -370.426 Kcal/mol, while the supramolecular ternary complex alone was -38.732 Kcal/mol, with a potential energy difference of -331.694 Kcal/mol, which favors the supramolecular ternary complex at Akt active site binding. In addition, the said combination increased cell viability by 267% and reduced morphological changes induced by Pentylenetetrazol (PTZ) in HEK-293 cells, which indicates the neuroprotective property of said combination. To conclude, we are the first to report the anti-convulsant and neuroprotective potential of the trio-drug combination.
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Computational approach to study of neuronal impairment is rapidly evolving, as experiments and intuition alone could not explain the complexity of brain system. The increase in an overwhelming amount of new data from both theory and computational modeling necessitate the development of databases and tools for analysis, visualization, and interpretation of neuroscience data. To ensure the sustainability of this development, consistent update and training of young professionals are imperative. For this purpose, relevant articles, chapters, and modules are essential to keep abreast of developments. Therefore, this article seeks to outline the biological databases and analytical tools along with their applications. It's envisaged that knowledge along this line would be a "training recipe" for young talents and guide for professionals and researchers in neuroscience.
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Biologia Computacional , Bases de Dados Factuais , Doenças do Sistema Nervoso , HumanosRESUMO
Silver Phosphate, Ag3PO4, being a highly capable clinical molecule, an ultrasonic method was employed to synthesize the M-Ag3PO4, (M = Se, Ag, Ta) nanoparticles which were evaluated for antibacterial and cytotoxicity activities post-characterization. Escherichia coli and Staphylococcus aureus were used for antibacterial testing and the effects of sonication on bacterial growth with sub-MIC values of M-Ag3PO4 nanoparticles were examined. The effect of M-Ag3PO4 nanoparticles on human colorectal carcinoma cells (HCT-116) and human cervical carcinoma cells (HeLa cells) was examined by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide) assay and DAPI (4',6-diamidino-2-phenylindole) staining. Additionally, we analyzed the effect of nanoparticles on normal and non-cancerous human embryonic kidney cells (HEK-293). Ag-Ag3PO4 exhibited enhanced antibacterial activity followed by Ta-Ag3PO4, Ag3PO4, and Se-Ag3PO4 nanoparticles against E. coli. Whereas the order of antibacterial activity against Staphylococcus aureus was Ag3PO4 > Ag-Ag3PO4 > Ta-Ag3PO4 > Se-Ag3PO4, respectively. Percentage inhibition of E. coli was 98.27, 74.38, 100, and 94.2%, while percentage inhibition of S. aureus was 25.53, 80.28, 99.36, and 20.22% after treatment with Ag3PO4, Se-Ag3PO4, Ag-Ag3PO4, and Ta-Ag3PO4, respectively. The MTT assay shows a significant decline in the cell viability after treating with M-Ag3PO4 nanoparticles. The IC50 values for Ag3PO4, Se-Ag3PO4, Ag-Ag3PO4, and Ta-Ag3PO4 on HCT-116 were 39.44, 28.33, 60.24, 58.34 µg/mL; whereas for HeLa cells, they were 65.25, 61.27, 75.52, 72.82 µg/mL, respectively. M-Ag3PO4 nanoparticles did not inhibit HEK-293 cells. Apoptotic assay revealed that the numbers of DAPI stained cells were significantly lower in the M-Ag3PO4-treated cells versus control.
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Nanopartículas Metálicas , Nanopartículas , Antibacterianos/farmacologia , Brometos/farmacologia , Escherichia coli , Células HEK293 , Células HeLa , Humanos , Staphylococcus aureusRESUMO
Neurodegenerative disorders present with progressive and irreversible degeneration of the neurons. Alzheimer's disease (AD) is one of the most common neurodegenerative disorders affecting 50 million people worldwide (2017), expected to be doubled every 20 years. Primarily affected by age, AD is the cause for old-age dementia, progressive memory loss, dysfunctional thoughts, confusion, cognitive impairment and personality changes. Neuroglia formerly understood as "glue" of the brain neurons consists of macroglia (astrocytes and oligodendrocyte), microglia and progenitors NG2-glia, and constitute a large fraction of the mammalian brain. The primary functions of glial cells are to provide neurons with metabolic and structural support in the healthy brain; however, they attain a "reactive" state from the "resting" state upon challenged with a pathological insult such as a neurodegenerative cascade. Failure or defects in their homoeostatic functions (i.e. concentration of ions, neurotransmitters) ultimately jeopardize neurons with excitotoxicity and oxidative stress. Moreover, the most common clinical outcome of AD is the cognitive impairment and memory loss, which are attributed mainly by the accumulation of Aß. Failure of glial cells to remove the Aß toxic proteins accelerates the AD progression. The rapidly emerging proteomic techniques such as mass spectrometry (MS), cross-linking mass spectrometry, hydrogen deuterium trade mass spectrometry, protein foot printing and 2-DGE combined with LC-MS/MS present wide array of possibilities for the identification of differentially expressed proteins in AD.
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Doença de Alzheimer , Animais , Cromatografia Líquida , Neuroglia , Neurônios , Proteômica , Espectrometria de Massas em TandemRESUMO
COVID-19 emerged in Wuhan, China in December 2019 has now spread around the world causes damage to human life and economy. Pakistan is also severely effected by COVID-19 with 202,955 confirmed cases and total deaths of 4,118. Vector Autoregressive time series models was used to forecast new daily confirmed cases, deaths and recover cases for ten days. Our forecasted model results show maximum of 5,363/day new cases with 95% confidence interval of 3,013-8,385 on 3rd of July, 167/day deaths with 95% confidence interval of 112-233 and maximum recoveries 4,016/day with 95% confidence interval of 2,182-6,405 in the next 10 days. The findings of this research may help government and other agencies to reshape their strategies according to the forecasted situation. As the data generating process is identified in terms of time series models, then it can be updated with the arrival of new data and provide forecasted scenario in future.
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In this study, we investigated Cu-Co ferrite nanofibers (NFs) that were synthesized for the first time employing the electrospinning technique. The structure, phase purity and crystallite size of all the prepared NFs were revealed by powder X-ray diffraction (PXRD) analysis. The NFs crystallized in the Fd3Ìm (no. 227) space group and the cation distribution arrangement over distinct sites in their structure was analyzed. Scanning electron microscopy (SEM) together with energy-dispersive X-ray (EDX) spectroscopy analysis showed the microstructure of the NFs and verified their expected chemical compositions. High-resolution transmission electron microscopy (TEM) images confirmed the fibrous nature and the construction of the NFs. The band gap energies derived from the UV-vis reflectance spectra showed a blue shift with an increase in the amount of Cu in the sample from 1.42 eV to 1.86 eV. Magnetization (M) as a function of magnetic field (H) measurements performed at ambient and low temperatures showed the ferrimagnetic behavior of all the NFs. The magnetic parameters including coercivity (Hc), saturation magnetization (Ms), remanent magnetization (Mr), and squareness ratio were determined from the recorded magnetization curves. At 300 K, Ms was reduced from 78.8 to 42.4 emu g-1, Mr reduced from 22.8 to 7.6 emu g-1 and the Bohr magneton reduced from 3.3 to 1.8µB with an increase in the content of Cu in the samples. The same trend was observed at 10 K, where Ms was reduced from 93.7 to 50.9 emu g-1, Mr reduced from 60.9 to 35.9 emu g-1 and the Bohr magneton reduced from 3.94 to 2.16µB. Alternatively, Hc has the highest values for x = 0 (850 Oe at 300 K and 5220 Oe at 10 K) and x = 0.6 (800 Oe at 300 K and 5400 Oe at 10 K). The anti-cancer activity of the NFs was evaluated using the MTT cell viability assay, showing a reduction in the viability of both HCT-116 and HeLa cancer cells compared to non-cancerous HEK-293 cells after treatment with the NFs. Apoptotic activity was examined by DAPI staining, where treatment with the NFs induced chromatin condensation and nuclear disintegration in HCT-116 cells.
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Worldwide, colon cancer is the third most frequent malignancy and the second most common cause of death. Although it can strike anybody at any age, colon cancer mostly affects the elderly. Small, non-cancerous cell clusters inside the colon, commonly known as polyps, are typically where colon cancer growth starts. But over time, if left untreated, these benign polyps may develop into malignant tissues and develop into colon cancer. For the diagnosis of colon cancer, with routine inspection of the colon region for polyps, several techniques, including colonoscopy and cancer scanning, are used. In the case identifying the polyps in the colon area, efforts are being taken to surgically remove the polyps as quickly as possible before they become malignant. If the polyps become malignant, then colon cancer treatment strategies, such as surgery, chemotherapy, targeted therapy, and immunotherapy, are applied to the patients. Despite the recent improvements in diagnosis and prognosis, the treatment of colorectal cancer (CRC) remains a challenging task. The objective of this review was to discuss how CRC is initiated, and its various developmental stages, pathophysiology, and risk factors, and also to explore the current state of colorectal cancer diagnosis and treatment, as well as recent advancements in the field, such as new screening methods and targeted therapies. We examined the limitations of current methods and discussed the ongoing need for research and development in this area. While this topic may be serious and complex, we hope to engage and inform our audience on this important issue.
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Traditional cancer diagnosis has been aided by the application of nanoparticles (NPs), which have made the process easier and faster. NPs possess exceptional properties such as a larger surface area, higher volume proportion, and better targeting capabilities. Additionally, their low toxic effect on healthy cells enhances their bioavailability and t-half by allowing them to functionally penetrate the fenestration of epithelium and tissues. These particles have attracted attention in multidisciplinary areas, making them the most promising materials in many biomedical applications, especially in the treatment and diagnosis of various diseases. Today, many drugs are presented or coated with nanoparticles for the direct targeting of tumors or diseased organs without harming normal tissues/cells. Many types of nanoparticles, such as metallic, magnetic, polymeric, metal oxide, quantum dots, graphene, fullerene, liposomes, carbon nanotubes, and dendrimers, have potential applications in cancer treatment and diagnosis. In many studies, nanoparticles have been reported to show intrinsic anticancer activity due to their antioxidant action and cause an inhibitory effect on the growth of tumors. Moreover, nanoparticles can facilitate the controlled release of drugs and increase drug release efficiency with fewer side effects. Nanomaterials such as microbubbles are used as molecular imaging agents for ultrasound imaging. This review discusses the various types of nanoparticles that are commonly used in cancer diagnosis and treatment.
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Nanotechnology has ultimately come into the domain of drug delivery. Nanosystems for delivery of drugs are promptly emerging science utilizing different nanoparticles as carriers. Biocompatible and stable nanocarriers are novel diagnosis tools or therapy agents for explicitly targeting locates with controllable way. Nanocarriers propose numerous advantages to treat diseases via site-specific as well as targeted delivery of particular therapeutics. In recent times, there are number of outstanding nanocarriers use to deliver bio-, chemo-, or immuno- therapeutic agents to obtain effectual therapeutic reactions and to minimalize unwanted adverse-effects. Nanoparticles possess remarkable potential for active drug delivery. Moreover, conjugation of drugs with nanocarriers protects drugs from metabolic or chemical modifications, through their way to targeted cells and hence increased their bioavailability. In this review, various systems integrated with different types of nanocarriers (inorganic. organic, quantum dots, and carbon nanotubes) having different compositions, physical and chemical properties have been discussed for drug delivery applications.
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Nanopartículas , Nanotubos de Carbono , Nanotubos de Carbono/química , Sistemas de Liberação de Medicamentos , Nanopartículas/química , Nanotecnologia , Preparações Farmacêuticas , Portadores de Fármacos/químicaRESUMO
Gold nanoparticles (AuNPs) and carbon nanotubes (CNTs) are increasingly being investigated for cancer management due to their physicochemical properties, low toxicity, and biocompatibility. This study used an eco-friendly technique (laser synthesis) to fabricate AuNP and Au/CNT nanocomposites. AuNPs, Au/CNTs, and CNTs were tested as potential cancer nanotherapeutics on colorectal carcinoma cells (HCT-116) and cervical cancer cells (HeLa) using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. In addition, the non-cancer embryonic kidney cells HEK-293 were taken as a control in the study. The cell viability assay demonstrated a significant reduction in cancer cell population post 48 h treatments of AuNPs, and Au/CNTs. The average cell viabilities of AuNPs, Au/CNTs, and CNTs for HCT-116 cells were 50.62%, 65.88%, 93.55%, and for HeLa cells, the cell viabilities were 50.88%, 66.51%, 91.73%. The cell viabilities for HEK-293 were 50.44%, 65.80%, 93.20%. Both AuNPs and Au/CNTs showed higher cell toxicity and cell death compared with CNT nanomaterials. The treatment of AuNPs and Au/CNTs showed strong inhibitory action on HCT-116 and HeLa cells. However, the treatment of CNTs did not significantly decrease HCT-116 and HeLa cells, and there was only a minor decrease. The treatment of AuNPs, and Au/CNTs, on normal HEK-293 cells also showed a significant decrease in cell viability, but the treatment of CNTs did not produce a significant decrease in the HEK-293 cells. This study shows that a simplified synthesis technique like laser synthesis for the preparation of high-purity nanomaterials has good efficacy for possible future cancer therapy with minimal toxicity.
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The revolution of biomedical applications has opened new avenues for nanotechnology. Zinc Chromium vanadate nanoparticles (VCrZnO4 NPs) have emerged as an up-and-coming candidate, with their exceptional physical and chemical properties setting them apart. In this study, a one-pot solvothermal method was employed to synthesize VCrZnO4 NPs, followed by a comprehensive structural and morphological analysis using a variety of techniques, including X-Ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, Energy-dispersive X-ray, and X-ray photoelectron spectroscopy. These techniques confirmed the crystallinity of the NPs. The VCrZnO4 NPs were tested for their antibacterial activity against primary contaminants such as Enterobacteriaceae, including Shigella flexneri, Salmonella cholerasis, and Escherichia coli, commonly found in hospital settings, using the broth dilution technique. The results indicated a stronger antibacterial activity of VCrZnO4 NPs against Shigella and Salmonella than E. coli. Electron microscopy showed that the NPs caused severe damage to the bacterial cell wall and membrane, leading to cell death. In addition, the study evaluated the anticancer activities of the metal complexes in vitro using colorectal cancer cells (HCT-116) and cervical cancer cells (HELA), along with non-cancer cells and human embryonic kidney cells (HEK-293). A vanadium complex demonstrated efficient anticancer effects with half-inhibitory concentrations (IC50) of 38.50+3.50 g/mL for HCT-116 cells and 42.25+4.15 g/mL for HELA cells. This study highlights the potential of Zinc Chromium vanadate nanoparticles as promising candidates for antibacterial and anticancer applications. Various advanced characterization techniques were used to analyze the properties of nanomaterials, which may help develop more effective and safer antibacterial and anticancer agents in the future.
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Nanotherapeutics have attracted tremendous research interest in the modern pharmaceutical and biomedical industries due to their potential for drug development, targeted delivery, and therapeutic applications. Therefore, the current study underpins the synthesis of praseodymium ion (Pr3+)-substituted Ni0.5Co0.5Fe2O4 nano-spinel ferrites, (Co0.5Ni0.5PrxFe2-xO4 (0.0 ≤ x ≤ 0.10) NSFs, CoNiPr (x ≤ 0.10) NSFs) via the sonochemical route for its application as a nanotherapeutic treatment option. The synthesized nanomaterial was characterized using various analytical techniques, including scanning/transmission electron microscopy (SEM) and X-ray powder diffractometry (XRD). After substitution with Pr (x = 0.08), the particle size, polydispersity index, and zeta potential analysis indicated an increase in hydrodynamic diameter, with an average zeta potential value of -10.2 mV. The investigation of CoNiPr (x ≤ 0.10) NSFs on colorectal cancer (HCT-116) cells demonstrated a significant effect on cancer cell viability. The inhibitory concentration (IC50) of CoNiPr (x ≤ 0.10) NSFs was between 46 ± 0.91 and 288 ± 8.21 for HCT-116 cells. The effect of CoNiPr (x ≤ 0.10) NSFs on normal human embryonic kidney (HEK-293) cells showed a reduction in the HEK-293 cell viability; however, the cell viability was better than HCT-116. The NSFs treatment also showed morphological changes in cancer cell nuclei, as revealed by DAPI (4',6-diamidino-2-phenylindole), nuclear disintegration, and chromatic fragmentation, which are signs of apoptosis or programmed cell death. To examine the potential antifungal effects of CoNiPr NSFs on Candida albicans, known to cause candidemia among cancer patients, the viability of the cells was assessed post treatment with CoNiPr (x ≤ 0.10) NSFs. The increasing ratio of dopant had a moderate impact on the percentage of cell viability loss of 42, 44, and 43% with x = 0.06, 0.08, and 0.10, respectively. These results reinforce that increased dopant significantly impacts the antifungal properties of the synthesized nanomaterial. These findings support the idea that NSFs might be useful in pharmaceuticals.
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Agriculture is one of the major contributors to the Gross Domestic Product (GDP) of Pakistan which relies on the availability of water. Hydropower contributes approximately 35% to the national electricity gid of Pakistan. Indus River is the main river of the Indus River System (IRS) which provides water for agriculture, hydropower and other purposes. The outputs of the Conformal-Cubic Atmospheric Model (CCAM) are used to force the University of British Columbia Watershed Model (UBCWM) in the Upper Indus Basin (UIB), to investigate future water availability under the two IPCC emission scenarios (RCP4.5 and RCP8.5). Tarbela Reservoir which is the outlet of UIB is used as a measurement tool to assess water availability and response of the reservoir to climate change. The results show that maximum and minimum temperature are increasing in the future in comparison to the reference period. The largest increases in maximum temperature are projected for MAM (March-April-May) and JJA (June-July-August), with increases up to 2 °C in MAM and increases up to 6.4 °C in JJA under the RCP4.5 and RCP8.5, respectively, in the future. Minimum temperature has maximum increase (6.7 °C) in DJF (December-January-February) during 2071-2100 under RCP8.5. Precipitation shows a 5.1% decrease in DJF during 2011-2040 under RCP4.5. The statistics about water availability suggest that there is consistent increase in most of the months in the future, however, under the RCP4.5, there is decline in the river flow during 2071-2100 as compared to the 2041-2070. The findings of this study show that most of the time there will be more water available but in some months, there may be water scarcity under the RCP4.5, however, proper management and optimal utilization can reduce the water scarcity.
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Rios , Água , Mudança Climática , Paquistão , Abastecimento de ÁguaRESUMO
Climate extremes, such as heat waves, droughts, extreme rainfall can lead to harvest failures, flooding and consequently threaten the food security worldwide. Improving our understanding about climate extremes can mitigate the worst impacts of climate change and extremes. The objective here is to investigate the changes in climate and climate extremes by considering two time slices (i.e., 1962-1990 and 1991-2019) in all climate zones of Pakistan by utilizing observed data from 54 meteorological stations. Different statistical methods and techniques were applied on observed station data to assess changes in temperature, precipitation and spatio-temporal trends of climatic extremes over Pakistan from 1962 to 2019. The Mann-Kendal test demonstrated increasing precipitation (DJF) and decreasing maximum and minimum temperatures (JJA) at the meteorological stations located in the Karakoram region during 1962-1990. The decadal analysis, on the other hand, showed a decrease in precipitation during 1991-2019 and an increase in temperature (maximum and minimum) during 2010-2019, which is consistent with the recently observed slight mass loss of glaciers related to the Karakoram Anomaly. These changes are highly significant at 5% level of significance at most of the stations. In case of temperature extremes, summer days (SU25) increased except in zone 4, TX10p (cold days) decreased across the country during 1962-1990, except for zones 1 and 2. TX90p (warm days) increased between 1991-2019, with the exception of zone 5, and decreased during 1962-1990, with the exception of zones 2 and 5. The spatio-temporal trend of consecutive dry days (CDD) indicated a rising tendency from 1991 to 2019, with the exception of zone 4, which showed a decreasing trend. PRCPTOT (annual total wet-day precipitation), R10 (number of heavy precipitation days), R20 (number of very heavy precipitation days), and R25mm (very heavy precipitation days) increased (decreased) considerably in the North Pakistan during 1962-1990 (1991-2019). The findings of this study can help to address some of the sustainable development goals related climate action, hunger and environment. In addition, the findings can help in developing sustainable adaptation and mitigation strategies against climate change and extremes. As the climate and extremes conditions are not the uniform in all climate zone, therefore, it is suggested to the formers and agriculture department to harvest crops resilient to the climatic condition of each zone. Temperature has increasing trend in the northern Pakistan, therefore, the concerned stakeholders need to make rational plans for higher river flow/flood situation due to snow and glacier melt.
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Mudança Climática , Rios , Camada de Gelo , Paquistão , TemperaturaRESUMO
Hollow silica spheres (HSS) exhibited high-specific surface area, low toxicity, low density, and good biocompatibility. The effectivity of HSS material can be improved further by loading nanoparticles for smart biological applications. In this work, magnetic nanoparticle (iron oxide; Fe3O4)-loaded pure HSS (c-HSS-Fe) were synthesized successfully using a template-free chemical route and investigated for their anticancer cell proliferation capabilities against cancerous cell lines: human colorectal carcinoma cells (HCT-116). The structure, morphology, chemical bonding, and thermal stability of the prepared HSS derivatives were studied using spectroscopic and microscopic techniques. Our analyses confirmed the successful preparation of Fe3O4 loaded HSS material (sphere diameter â¼515 nm). The elemental analysis revealed the existence of Fe along with Si and O in the Fe3O4 loaded HSS material, thus reaffirming the production of the c-HSS-Fe product. The effects of silica spheres on HCT-116 cells were examined microscopically and by MTT assays. It was observed that the c-HSS-Fe demonstrated dose-dependent behavior and significantly reduced the cancer cell proliferation at higher doses. Our results showed that c-HSS-Fe was more effective and profound in reducing the cancer cells' activities as compared to unloaded HSS material where the cancer cells have undergone nuclear disintegration and fragmentation. It is concluded that c-HSS-Fe is a powerful bio-active material against cancerous cells.
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A series of 27 new quinoxaline derivatives (N-alkyl-[2-(3-phenyl-quinoxalin-2-ylsulfanyl)]acetamides, methyl-2-[2-(3-phenylquinoxalin-2-ylsulfanyl)-acetylamino]alkanoates, and their corresponding dipeptides) were prepared from 3-phenylquinoxaline-2(1H)-thione based on the chemoselective reaction with soft electrophiles. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to study the efficacy of 27 compounds on cancer cell viability and proliferation. A total of 13 compounds (4a-c, 5, 6, 8c, 9c, 9f, 10a, 10b, 11c, 12b, and 12c) showed inhibitory action on HCT-116 cancer cells and 15 compounds (4a-c, 5, 6, 8c, 9a, 9c, 9f, 9h, 10b, 11c, 12a, 12b, and 12c) showed activity on MCF-7 cancer cells, with compound 10b exhibiting the highest inhibitory action (IC50 1.52 and 2 µg/mL, respectively) on both cell lines. The molecular modeling studies on the human thymidylate synthase (hTS) homodimer interface showed that these compounds are good binders and could selectively inhibit the enzyme by stabilizing its inactive conformation. The study also identified key residues for homodimer binding, which could be used for further optimization and development.