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1.
Liver Transpl ; 2024 May 14.
Article in English | MEDLINE | ID: mdl-38738964

ABSTRACT

For many cancers, biomarkers have served as an important tool across the cancer care continuum from risk stratification and early detection to diagnosis and treatment. Alpha-fetoprotein (AFP) remains one of the few validated biomarkers for patients with HCC. Although AFP has shown potential for each of these steps, its performance, when used alone, has often been suboptimal. There continue to be discordant recommendations about AFP's value when combined with ultrasound for surveillance, as well as its role in diagnostic algorithms. Conversely, high AFP levels are associated with aggressive tumor biology and survival, so it remains a key factor for the selection of candidates for liver transplant. There have been immense efforts to identify and validate additional biomarkers for each of these steps in the HCC care continuum. Indeed, biomarker panels have shown promising data for HCC risk stratification and surveillance among patients with cirrhosis, as well as prognostication and detection of minimal residual disease in patients undergoing HCC treatment. Several large prospective studies are currently ongoing to evaluate the role of these emerging biomarkers in clinical practice.

2.
BMC Infect Dis ; 24(1): 150, 2024 Jan 31.
Article in English | MEDLINE | ID: mdl-38297213

ABSTRACT

BACKGROUND: Bacterial infections are considered a leading cause of hospitalization and death globally. There is still a need for a rapid and feasible biomarker for bacterial infections. Heparin-binding protein (HBP) was shown to be related to bacterial infections. The objective of the study is to investigate the diagnostic accuracy of HBP in bacterial infections. METHODS: Articles were screened in PubMed, SCOPUS, Web of Science, and Cochrane to recognize eligible studies. We included studies investigating the diagnostic accuracy of HBP and reported the necessary data to construct 2 × 2 tables. A univariate analysis was conducted to determine the pooled sensitivity and specificity, and a bivariate diagnostic random-effects model was used to calculate the optimal cut-off point. RESULTS: The analysis comprised sixteen studies in total. Plasma HBP showed a sensitivity of 0.90 (95% CI: [0.79, 0.96]) and a specificity of 0.87 (95% CI: [0.66, 0.96]) in diagnosing bacterial infections using blood samples. Pooling data from seven studies revealed that HBP in cerebrospinal fluid (CSF) has sensitivity and specificity of 96% (95% CI: [0.85, 0.99]), and 95% (95% CI: [0.89, 0.97]), respectively, for the diagnosis of bacterial meningitis. In urinary tract infections (UTI), urine-HBP was revealed to have a high diagnostic value in discriminating bacterial from non-bacterial UTI infection at a cut-off value of 32.868 ng/ml with sensitivity and specificity of 87%. CONCLUSION: HBP has shown a high diagnostic accuracy of bacterial infections, including UTI and meningitis. Further studies are needed to determine its prognostic value and whether it could guide antibiotic therapy.


Subject(s)
Blood Proteins , Meningitis, Bacterial , Urinary Tract Infections , Humans , Sensitivity and Specificity , Urinary Tract Infections/diagnosis , Antimicrobial Cationic Peptides , Meningitis, Bacterial/diagnosis
3.
Chirality ; 36(2): e23642, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38384155

ABSTRACT

Helicenes represent an important class of chiral organic material with promising optoelectronic properties. Hence, functionalization of surfaces with helicenes is a key step toward new organic materials devices. The deposition of a heterohelicene containing two furano groups and two hydroxyl groups onto copper(111) surface in ultrahigh vacuum leads to different adsorbate modifications. At low coverage and low temperature, the molecules tend to lie on the surface in order to maximize van der Waals contact with the substrate. Thermal treatment leads to deprotonation of the hydroxyl groups and in part into a reorientation from lying into a standing adsorbate mode.

4.
Aesthetic Plast Surg ; 2024 May 17.
Article in English | MEDLINE | ID: mdl-38760539

ABSTRACT

BACKGROUND: Laser therapy has emerged as a promising treatment modality for improving the appearance and symptoms associated with hypertrophic and keloid scars. In this network meta-analysis, we aimed to evaluate the efficacy of different laser types in treating hypertrophic and keloid scars. METHODS: A comprehensive search of four databases was conducted to identify relevant studies published up until July 2023. Data were extracted from eligible studies and pooled as mean difference (MD) for continuous outcomes and risk ratio (RR) for dichotomous data in a network meta-analysis (NMA) model, using R software. RESULTS: A total of 18 studies, comprising 550 patients, were included in the analysis. Pooling our data showed that fractional carbon dioxide (FCO2) plus 5-fluorouracil (5-FU) was superior to control in terms of Vancouver Scar Scale (VSS), pliability score, and thickness; [MD = - 5.97; 95% CI (- 7.30; - 4.65)], [MD = - 2.68; 95% CI (- 4.03; - 1.33)], [MD = - 2.22; 95% CI (- 3.13; - 1.31)], respectively. However, insignificant difference was observed among FCO2 plus 5-FU compared to control group in terms of erythema, vascularity, redness and perfusion, and pigmentation [MD = - 0.71; 95% CI (- 2.72; 1.30)], [MD = - 0.44; 95% CI (- 1.26; 0.38)], respectively. CONCLUSION: Our NMA found that the FCO2 plus 5-FU was the most effective intervention in decreasing the VSS and thickness, while FCO2 plus CO2 was the most effective intervention in decreasing the pliability score. Further research is needed to determine the optimal laser parameters and long-term efficacy of laser therapy in hypertrophic and keloid scars. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these evidence-based medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

5.
J Nutr ; 153(1): 352-363, 2023 01.
Article in English | MEDLINE | ID: mdl-36913472

ABSTRACT

BACKGROUND: Anemia and iron deficiency have been associated with poor child cognitive development. A key rationale for the prevention of anemia using supplementation with iron has been the benefits to neurodevelopment. However, little causal evidence exists for these gains. OBJECTIVES: We aimed to examine effects of supplementation with iron or multiple micronutrient powders (MNPs) on brain activity measures using resting electroencephalography (EEG). METHODS: Children included in this neurocognitive substudy were randomly selected from the Benefits and Risks of Iron Supplementation in Children study, a double-blind, double-dummy, individually randomized, parallel-group trial in Bangladesh, in which children, starting at 8 mo of age, received 3 mo of daily iron syrup, MNPs, or placebo. Resting brain activity was recorded using EEG immediately after intervention (month 3) and after a further 9-month follow-up (month 12). We derived EEG band power measures for delta, theta, alpha, and beta frequency bands. Linear regression models were used to compare the effect of each intervention with that of placebo on the outcomes. RESULTS: Data from 412 children at month 3 and 374 at month 12 were analyzed. At baseline, 43.9% were anemic and 26.7% were iron deficient. Immediately after intervention, iron syrup, but not MNPs, increased the mu alpha-band power, a measure that is associated with maturity and the production of motor actions (iron vs. placebo: mean difference = 0.30; 95% CI: 0.11, 0.50 µV2; P = 0.003; false discovery rate adjusted P = 0.015). Despite effects on hemoglobin and iron status, effects were not observed on the posterior alpha, beta, delta, and theta bands, nor were effects sustained at the 9-month follow-up. CONCLUSIONS: The effect size for immediate effects on the mu alpha-band power is comparable in magnitude with psychosocial stimulation interventions and poverty reduction strategies. However, overall, we did not find evidence for long-lasting changes in resting EEG power spectra from iron interventions in young Bangladeshi children. This trial was registered at www.anzctr.org.au as ACTRN12617000660381.


Subject(s)
Anemia, Iron-Deficiency , Anemia , Humans , Child , Iron , Powders , Dietary Supplements , Anemia, Iron-Deficiency/prevention & control , Anemia, Iron-Deficiency/drug therapy , Micronutrients , Anemia/drug therapy , Brain
6.
Drug Chem Toxicol ; 46(3): 588-596, 2023 May.
Article in English | MEDLINE | ID: mdl-35506235

ABSTRACT

Kava is a herbal supplement and beverage made from the Piper methysticum plant, which is known for its recreational use as a mood enhancer, relaxation, as well as pain relief for centuries. Kava is widely used among alcoholics, but it is dangerous and potentially fatal. The objectives of this study were to examine the sub-acute toxicity effects of different doses of 70% kavalactone (KL) in rats by oral application, as well as to elucidate the mechanisms of toxicity alone and in combination with ethanol (EtOH). The most common side effects observed were abnormal breathing, ataxia, lethargy, loss of appetite, indigestion, and loss of coordination, especially in the 800 mg/kg bw, po bodyweight dosage of kava treatment group alone, and in combination with EtOH. In the sub-acute study, there were dose-related decreases in body weight, feed intake, and water consumption rates. Gross and histopathological findings revealed that the liver was abnormal in color, size, consistency, and the weight significantly increased at a dose of 800 mg/kg bw, po, with KL alone and a greater increase in combination with EtOH. Hepatocellular hypertrophy (HP) and necrosis with Kupffer cells hyperplasia were observed in the periacinar zone of all rats dosed with KL (800 mg/kg bw, po) alone, and extensive changes were observed in combination with EtOH. The periportal (Z1) and mid-zonal (Z2) areas of hepatocytes were less affected as compared to the periacinar zone. These results demonstrate that EtOH exacerbated the sedative and hypnotic activity of KL, and markedly increased toxicity. The histopathological results supported the clinical and biochemical findings and the severity of hepatic damage in a dose-dependent manner.


Subject(s)
Ethanol , Liver , Rats , Animals , Ethanol/toxicity , Dietary Supplements
7.
BMC Endocr Disord ; 22(1): 113, 2022 Apr 29.
Article in English | MEDLINE | ID: mdl-35488292

ABSTRACT

BACKGROUND: The food and drug administration approved many drugs to treat diabetes mellitus, but those drugs do not have a noticeable effect on weight management. Recently, glucagon-like peptide 1 agonist known as Cotadutide serve as a potent drug in treating type 2 diabetes by reducing blood glucose levels and body weight indices. This study aimed to explore the safety and efficacy of Cotadutide as a treatment for type 2 diabetes individuals. METHODS: A comprehensive literature search was done on different databases, including PubMed, Scopus, Web of Science, and Cochrane Library to capture all relevant articles using an established search strategy. The inclusion criteria were randomized controlled trials that assessed the safety and efficacy of Cotadutide versus placebo or any anti-diabetes drugs in patients with type 2 diabetes mellitus and a BMI between 22 kg/m2 and 40 kg/m2. We conducted the analysis using Revman software version 5.4. RESULTS: We found 663 relevant articles. From which nine studies were included and subjected to qualitative analysis and eight for quantitative analysis. The pooled effect showed that Cotadutide was better than placebo in reducing body weight (kg) (Mean difference (MD) = 3.31, p < 0.00001), glycated hemoglobin (HbA1c) (MD = 0.68, p > 0.00001), glucose area under the plasma concentration curve (AUC [0-4 h]) (MD = 30.15, p < 0.00001), and fasting plasma glucose over time (mg/dl) (MD = 31.31, p < 0.00001). CONCLUSION: Cotadutide is safe and effective in reducing plasma glucose levels, HbA1c and body weight in individuals with type 2 diabetes. TRIAL REGISTRATION: The study protocol was registered on PROSPERO (CRD: CRD42021257670 ).


Subject(s)
Diabetes Mellitus, Type 2 , Blood Glucose , Body Weight , Diabetes Mellitus, Type 2/drug therapy , Humans , Peptides , Pharmaceutical Preparations , Randomized Controlled Trials as Topic , United States
8.
BMC Pregnancy Childbirth ; 22(1): 581, 2022 Jul 21.
Article in English | MEDLINE | ID: mdl-35864455

ABSTRACT

BACKGROUND AND OBJECTIVE: More than five million individuals died because of problems connected to COVID-19. SARS-Cov-2 poses a particular challenge to expectant mothers, who comprise one of the most vulnerable segments of the population. Our aim is to demonstrate the maternal and neonatal safety of the COVID-19 vaccine during pregnancy. METHODS: We searched PubMed, Cochrane Library, Scopus, Web of Science (WOS), Embase, Ovid, MedRxiv, and BioRxiv databases from inception till December 2021 and then updated it in April 2022. Additionally, we searched ClinicalTrials.gov, Research Square and grey literature. Cohort, case-control studies, and randomized controlled trials detecting the safety of the Covid-19 vaccine during pregnancy were included. We used the Cochrane tool and Newcastle-Ottawa Scale to assess the risk of bias of the included studies and the GRADE scale to assess the quality of evidence. A meta-analysis was conducted using review manager 5.4. RESULTS: We included 13 studies with a total number of 56,428 patients. Our analysis showed no statistically significant difference in the following outcomes: miscarriage (1.56% vs 0.3%. RR 1.23; 95%CI 0.54 to 2.78); length of maternal hospitalization (MD 0.00; 95%CI -0.08 to 0.08); puerperal fever (1.71% vs 1.1%. RR 1.04; 95%CI 0.67 to 1.61); postpartum hemorrhage (4.27% vs 3.52%. RR 0.84; 95%CI 0.65 to 1.09); instrumental or vacuum-assisted delivery (4.16% vs 4.54%. RR 0.94; 95%CI 0.57 to 1.56); incidence of Apgar score ≤ 7 at 5 min (1.47% vs 1.48%. RR 0.86; 95%CI 0.54 to 1.37); and birthweight (MD -7.14; 95%CI -34.26 to 19.99). CONCLUSION: In pregnancy, the current meta-analysis shows no effect of SAR-CoV-2 vaccination on the risk of miscarriage, length of stay in the hospital, puerperal fever, postpartum hemorrhage, birth weight, or the incidence of an Apgar score of ≤ 7 at 5 min.


Subject(s)
COVID-19 , Pregnancy Complications , Abortion, Spontaneous , Birth Weight , COVID-19/epidemiology , COVID-19/prevention & control , COVID-19 Vaccines/adverse effects , Female , Humans , Infant, Newborn , Length of Stay , Postpartum Hemorrhage , Pregnancy , Pregnancy Complications/etiology , SARS-CoV-2 , Vaccination/adverse effects
9.
Heart Surg Forum ; 25(4): E545-E547, 2022 Jul 14.
Article in English | MEDLINE | ID: mdl-36052901

ABSTRACT

Gerbode defect is a rare defect describing a left ventricle to right atrium shunt with symptoms dependent on the size and degree of the shunt. It is either a congenital defect detected in infancy, or an acquired case reported in older age. Diagnosis by means of echocardiography and cardiac magnetic resonance imaging is of paramount importance before surgical correction is contemplated to achieve a good prognosis.


Subject(s)
Heart Failure , Heart Septal Defects, Atrial , Heart Septal Defects, Ventricular , Adult , Echocardiography , Heart Atria/surgery , Heart Failure/complications , Heart Failure/etiology , Heart Septal Defects, Atrial/surgery , Heart Septal Defects, Ventricular/complications , Heart Septal Defects, Ventricular/diagnosis , Heart Septal Defects, Ventricular/surgery , Heart Ventricles/surgery , Humans
10.
Molecules ; 27(20)2022 Oct 11.
Article in English | MEDLINE | ID: mdl-36296397

ABSTRACT

Saponins are triterpenoid or steroidal glycosides and are an important group of naturally occurring compounds of plant origin. They exhibit diverse pharmacological potentials including radical scavenging, as well as neuroprotective, anti-diabetic and anti-inflammatory activities, owing to their diverse chemical scaffolds. Saponins consist of an aglycone part (non-sugar) and a glycone part (sugar) and have at least one glycosidic (C-O sugar bond) linkage present between the glycone and aglycone mostly at C-3. On the basis of the aglycone part, saponins are classified into triterpenoid glycosides, steroid glycosides and alkaloid glycosides. Saponins exhibit neuroprotective activities against various disorders of the central nervous system (CNS) including stroke, Alzheimer's disease (AD), Huntington's disease (HD) and Parkinson's disease (PD). They mediate their therapeutic effects by modulation of various pathological targets. This study highlights various neuroprotective mechanisms of saponins including free radical scavenging, modulation of neuroprotective signaling pathways, activation of neurotrophic factors, modulation of neurotransmitters, inhibition of BACE1 enzyme and tau hyper-phosphorylation. The study concludes that saponins have considerable efficacy against various pathological targets of neurological disorders, especially AD, and might be an important source of leads against neurodegenerative disorders.


Subject(s)
Alzheimer Disease , Neurodegenerative Diseases , Saponins , Triterpenes , Humans , Saponins/chemistry , Alzheimer Disease/drug therapy , Public Health , Amyloid Precursor Protein Secretases , Aspartic Acid Endopeptidases , Neurodegenerative Diseases/drug therapy , Triterpenes/chemistry , Glycosides/therapeutic use , Nerve Growth Factors , Neurotransmitter Agents/therapeutic use , Free Radicals , Steroids/therapeutic use
11.
BMC Public Health ; 21(1): 671, 2021 04 07.
Article in English | MEDLINE | ID: mdl-33827491

ABSTRACT

BACKGROUND: The misuse of illicit substances is associated with increased morbidity and mortality; thus, substance abuse is a global health concern. The Arabian Gulf region is considered a crossing point and a consumer of illicit drugs. However, a lack of laboratory-based research has limited the scientific assessment of drug misuse in the Arabian Gulf region. Thus, an up-to-date analytical representation of the drug situation is warranted. METHODS: We investigated the type and quantity of detained narcotic drugs and psychotropic substances from 2015 to 2018, representing a population of approximately 4 million people, in addition to the number of abusers and mortality among abusers. In total, 6220 cases from the Narcotic and Psychotropic Laboratory and 17,755 cases from the Forensic Toxicology Laboratory were reviewed and analyzed. Substances were identified and documented using gas chromatography-mass spectrometry and liquid chromatography-mass spectrometry. RESULTS: Cannabis, including marijuana, was the most seized substance, followed by heroin, opium, and cocaine. Amphetamines, including methamphetamine, in the form of powder or pills, were seized in larger quantities than other psychoactive substances. The most consumed substances were, in order, amphetamines (including methamphetamine), benzodiazepines, cannabis, and heroin. We identify the common drugs in postmortem specimens, according to sex, from suspected drug-related deaths. The most common single drug identified were heroin, benzodiazepines, and methamphetamine. Similarly, the multiple-drug cocktail of heroin-benzodiazepines, cannabis-benzodiazepines, and cannabis-amphetamines, were detected frequently. CONCLUSIONS: The data shows that cannabis is the leading type of illicit substance seized. Deaths resulting from benzodiazepines and heroin abuse were the highest in the single drug category, while heroin-benzodiazepines combination deaths were the highest in the multiple-drug category. Methamphetamine was the most abused illicit drug in Kuwait. These findings revealed the illicit drug abuse situation in the State of Kuwait, in a region that suffers from the scarcity of information regarding illicit substances. Thus, providing valuable information for drug enforcement, forensic analyst, health workers on national and international levels.


Subject(s)
Illicit Drugs , Substance-Related Disorders , Heroin , Humans , Kuwait , Narcotics , Psychotropic Drugs , Substance-Related Disorders/epidemiology
12.
J Org Chem ; 85(4): 1847-1860, 2020 02 21.
Article in English | MEDLINE | ID: mdl-31858799

ABSTRACT

Several regioselective functionalized mono- and disubstituted [7]oxa-helicenoids have been synthesized in the enantiomerically enriched (90-99% ee) form. These functionalized helicenoids exhibited pronounced spectral and chiroptical properties suitable for sensing applications. In particular, corresponding helicenoid's mono and dialdehydes have been effectively used as chemodosimeters for selective detection of cyanide anions over other anions, while simple aromatic aldehydes do not function as cyanide sensors. The groove available in the helical host plays a crucial role in the sensing. The enantiomerically enriched nature of the sensors allows the use of electronic circular dichroism as an uncommon detection tool for cyanide anions, along with conventional fluorescence and NMR methods.

13.
Sensors (Basel) ; 20(7)2020 Apr 06.
Article in English | MEDLINE | ID: mdl-32268475

ABSTRACT

The integration of the Internet of Things (IoT) with Wireless Sensor Networks (WSNs) typically involves multihop relaying combined with sophisticated signal processing to serve as an information provider for several applications such as smart grids, industrial, and search-and-rescue operations. These applications entail deploying many sensors in environments that are often random which motivated the study of beamforming using random geometric topologies. This paper introduces a new algorithm for the synthesis of several geometries of Collaborative Beamforming (CB) of virtual sensor antenna arrays with maximum mainlobe and minimum sidelobe levels (SLL) as well as null control using Canonical Swarm Optimization (CPSO) algorithm. The optimal beampattern is achieved by optimizing the current excitation weights for uniform and non-uniform interelement spacings based on the network connectivity of the virtual antenna arrays using a node selection scheme. As compared to conventional beamforming, convex optimization, Genetic Algorithm (GA), and Particle Swarm Optimization (PSO), the proposed CPSO achieves significant reduction in SLL, control of nulls, and increased gain in mainlobe directed towards the desired base station when the node selection technique is implemented with CB.

15.
Environ Monit Assess ; 192(3): 161, 2020 Feb 04.
Article in English | MEDLINE | ID: mdl-32020301

ABSTRACT

This study was aimed to biologically treat domestic wastewater using identified bacterial consortium for chemical pollutants removal by treating/passing it through sand biofilters. The identification, toxicity test, and the optimum dose of the investigated bacterial consortium were carried out using Microtox analyzer and Batch biological treatment, respectively. Furthermore, application of sedimentation followed by gravel and sand biofilters for wastewater treatment was evaluated. The results showed that the bacterial consortium is composed of Pediococcus acidilactici, Pediococcus pentosaceus, Lactobacillus plantarum, and Bacillus subtilis. The optimum dose for wastewater treatment within 6 h of contact time is 2.5 mg/L, this dose (2.5 mg/L) has no toxic effect. The removal percentage of chemical oxygen demand (COD), biological oxygen demand (BOD), total solids (TS), total dissolved solids (TDS), total suspended solids (TSS), ammonia, nitrate, total Kjeldahl nitrogen (TKN), and oil and grease reached 93.4, 83.5, 37.5, 49.2, 93.4, 100, 55.7, 76.6, and 76% in the effluent of the treated wastewater, respectively after the third sand biofilter filtration. It can be concluded that using bacterial consortium for domestic wastewater treatment could be a good tool for chemical pollutants removal. Moreover, this study provides low cost and eco-friendly tool for domestic wastewater treatment using simple multistage biofilters based on an identified bacterial consortium. This system can be upscaled for the treatment of larger volumes of wastewater.


Subject(s)
Wastewater , Water Purification , Bioreactors , Egypt , Environmental Monitoring , Nitrogen , Oxygen , Waste Disposal, Fluid
16.
J Org Chem ; 84(2): 860-868, 2019 01 18.
Article in English | MEDLINE | ID: mdl-30592416

ABSTRACT

Synthesis of [5]- and [7]oxahelicenoids via Diels-Alder reaction of sterically crowded bichromenes with benzyne is presented. Studies carried out on Diels-Alder addition product establish the unusual preference for a stepwise mechanism over the concerted reaction pathway. This high yielding general synthetic protocol affords unexpected anti cycloadducts [5]- and [7]oxahelicenoids, as confirmed by crystallographic analysis. To rationalize these intriguing antiaddition products, the reaction mechanism was elucidated by means of DFT analysis. Additionally, hydroxy-functionalized [7]oxahelicenoid has been resolved in its optically pure forms.

17.
Anal Chem ; 90(11): 6952-6958, 2018 06 05.
Article in English | MEDLINE | ID: mdl-29727561

ABSTRACT

Conformational switching induced in ethane-bridged bisporphyrins was used as a sensitive transduction method for revealing the presence of urea dissolved in water via nonenzymatic approach. Bisporphyrins were deposited on solid quartz slides by means of the spin-coating method. Molecular conformations of Zn and Ni monometalated bis-porphyrins were influenced by water solvated urea molecules and their fluorescence emission was modulated by the urea concentration. Absorption, fluorescence and Raman spectroscopies allowed the identification of supramolecular processes, which are responsible for host-guest interaction between the active layers and urea molecules. A high selectivity of the sensing mechanism was highlighted upon testing the spectroscopic responses of bis-porphyrin films to citrulline and glutamine used as interfering agents. Additionally, potential applicability was demonstrated by quantifying the urea concentration in real physiological samples proposing this new approach as a valuable alternative analytical procedure to the traditionally used enzymatic methods.


Subject(s)
Ethane/chemistry , Organometallic Compounds/chemistry , Porphyrins/chemistry , Urea/analysis , Molecular Conformation , Organometallic Compounds/chemical synthesis
18.
Analyst ; 143(5): 1042-1045, 2018 Feb 26.
Article in English | MEDLINE | ID: mdl-29431753

ABSTRACT

Marine microalgae have been identified as a considerable sink of atmospheric CO2. Since macroscopic ecosystems cannot be studied experimentally with the required microscopic spatial resolution, a novel modeling method is being presented to quantify this sequestration process. The presented modeling studies indicate that the fixation of carbon by microalgae is species-specific and depends on competition effects among multiple species.

19.
Bioorg Med Chem Lett ; 28(6): 1077-1083, 2018 04 01.
Article in English | MEDLINE | ID: mdl-29456109

ABSTRACT

Hepatocellular carcinoma (HCC) remains one of the leading causes of death worldwide. The complex etiology is attributed to many factors like heredity, cirrhosis, hepatitis infections or the dysregulation of the different molecular pathways. Nevertheless, the current treatment regimens have either severe side effects or tumors gradually acquire resistance upon prolonged use. Thus, developing a new selective treatment for HCC is the need of the hour. Many anticancer agents derived from plants have been evaluated for their cytotoxicity towards many human cancer cell lines. Strigolactones (SLs)-a newly discovered class of phytohormones, play a crucial role in the development of plant-root and shoot. Recently, many synthetic analogues of SLs have demonstrated pro-apoptotic effects on different cancer cell lines like prostate, breast, colon and lung. In this study, we tested synthetic SLs analogues on HCC cell line-HepG2 and evaluated their capability to induce cell proliferation inhibition and apoptosis. Primary WST-1 assays, followed by annexin-V/7AAD staining, demonstrated the anti-proliferative effects. The SLs analogues TIT3 and TIT7 were found to significantly reduce HepG2 cell viability in a dose- and time-dependent manner and induce apoptosis. Interestingly, though TIT3 and TIT7 strongly affected cancer cell proliferation, both compounds showed moderate anti-proliferative effect on normal cells. Further, migration of cancer cells was suppressed upon treatment with TIT3 and TIT7 in a wound healing assay. In summary, these findings suggest that two SLs analogues TIT3 and TIT7 exert selective inhibitory effects on cancer cells most likely through targeting microtubules. SLs analogues could be used in future as potential anti-cancer candidates in chemotherapy.


Subject(s)
Antineoplastic Agents/pharmacology , Carcinoma, Hepatocellular/drug therapy , Lactones/pharmacology , Liver Neoplasms/drug therapy , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Carcinoma, Hepatocellular/pathology , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Hep G2 Cells , Humans , Lactones/chemical synthesis , Lactones/chemistry , Liver Neoplasms/pathology , Molecular Structure , Structure-Activity Relationship
20.
Analyst ; 142(21): 4089-4098, 2017 Oct 23.
Article in English | MEDLINE | ID: mdl-29018852

ABSTRACT

Marine phytoplankton acts as a considerable sink of atmospheric CO2 as it sequesters large quantities of this greenhouse gas for biomass production. To assess microalgae's counterbalancing of global warming, the quantities of CO2 they fix need to be determined. For this task, it is mandatory to understand which environmental and physiological parameters govern this transformation from atmospheric CO2 to microalgal biomass. However, experimental analyses are challenging as it has been found that the chemical environment has a major impact on the physiological properties of the microalgae cells (diameter typ. 5-20 µm). Moreover, the cells can only chemically interact with their immediate vicinity and thus compound sequestration needs to be studied on a microscopic spatial scale. Due to these reasons, computer simulations are a more promising approach than the experimental studies. Modeling software has been developed that describes the dissolution of atmospheric CO2 into oceans followed by the formation of HCO3- which is then transported to individual microalgae cells. The second portion of this model describes the competition of different cell species for this HCO3-, a nutrient, as well as its uptake and utilization for cell production. Two microalgae species, i.e. Dunaliella salina and Nannochloropsis oculata, were cultured individually and in a competition situation under different atmospheric CO2 conditions. It is shown that this novel model's predictions of biomass production are in very good agreement with the experimental flow cytometry results. After model validation, it has been applied to long-term prediction of phytoplankton generation. These investigations were motivated by the question whether or not cell production slows down as cultures grow. This is of relevance as a reduced cell production rate means that the increase in a culture's CO2-sinking capacity slows down as well. One implication resulting from this is that an increase in anthropogenic CO2 may not be counterbalanced by an increase in phytoplankton production. Modeling studies have found that for several different atmospheric CO2 levels provided to single-species cultures as well as to species in competing scenarios the cell production rate does slow down over time.

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