34 research outputs found
Alkaloids from Oxytropis ochrocephala and antiproliferative activity of sophoridine derivatives against cancer cell lines
Ten alkaloids (1-10), with sophoridine (1) as the most abundant component, were obtained from the whole plants of Oxytropis ochrocephala Bunge. Furthermore, eight new sophoridine derivatives (11-16, 20, 21), with modification on the C-14 position of 1 were synthesized. All compounds (1-16, 20, 21) were evaluated for antiproliferative activity against five human tumor cell lines. Among them, the newly synthesized derivative 20 exhibited the best inhibitory activity against the tested cell lines. Its activity was increased by more than fourfold as compared with parent compound 1
Selective cytotoxic eremophilane-type sesquiterpenes from Penicillium citreonigrum
One new eremophilane-type sesquiterpene (1, citreopenin) was isolated from Penicillium citreonigrum ({"type":"entrez-nucleotide","attrs":{"text":"HQ738282","term_id":"328929979","term_text":"HQ738282"}}HQ738282), and the structure was elucidated by a combination of spectroscopic data interpretation and single-crystal X-ray diffraction analysis using Cu Kα radiation (CCDC 1030588). Compound 1 showed weak activity against KB-VIN (IC50 = 11.0 ± 0.156 μM), while the known compound 3 exhibited selective cytotoxicity against MDA-MB-231 triple-negative breast cancer (TNBC) (IC50 = 5.42 ± 0.167 μM)
Multidrug resistance-selective antiproliferative activity of Piper amide alkaloids and synthetic analogues
Twenty-five amide alkaloids (1–25) from Piper boehmeriifolium and 10 synthetic amide alkaloid derivatives (39–48) were evaluated for antiproliferative activity against eight human tumor cell lines, including chemosensitive and multidrug-resistant (MDR) cell lines. The results suggested tumor type-selectivity. 1-[7-(3,4,5-Trimethoxyphenyl)heptanoyl]piperidine (46) exhibited the best inhibitory activity (IC50 = 4.94 µM) against the P-glycoprotein (P-gp)-overexpressing KBvin MDR sub-line, while it and all other tested compounds, except 9, were inactive (IC50 >40 µM) against MDA-MB-231 and SK-BR-3. Structure-activity relationships (SARs) indicated that (i) 3,4,5-trimethoxy phenyl substitution is critical for selectivity against KBvin, (ii) the 4-methoxy group in this pattern is crucial for antiproliferative activity, (iii) double bonds in the side chain are not needed for activity, and (iv), in arylalkenylacyl amide alkaloids, replacement of an isobutylamino group with pyrrolidin-1-yl or piperidin-1-yl significantly improved activity. Further study on Piper amides is warranted, particularly whether side chain length affects the ability to overcome the MDR cancer phenotype
Optimization of N-aryl-6-methoxy-1,2,3,4-tetrahydroquinolines as tubulin polymerization inhibitors
Thirteen new -aryl 1,2,3,4-tetrahydroquinoline compounds (–, –, and –) were synthesized and evaluated for antitumor activity and drug-like properties. Compound exhibited high inhibitory potency with low nanomolar GI values of 16–20 nM in cellular assays, including excellent activity against the P-glycoprotein overexpressing cell line KBvin. Compound inhibited colchicine binding to tubulin and tubulin assembly with an IC value of 0.85 μM, superior to the reference compound CA4 (1.2 μM) in the same assay. In addition, also exhibited highly improved water solubility (75 μg/mL) and a suitable log value (3.43) at pH 7.4. With a good balance between antitumor potency and drug-like properties, compound could be a new potential drug candidate for further development. Current results on SAR studies and molecular modeling provided more insight about this class of compounds as tubulin polymerization inhibitors targeting the colchicine site
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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
YC-1 Prevents Tumor-Associated Tissue Factor Expression and Procoagulant Activity in Hypoxic Conditions by Inhibiting p38/NF-κB Signaling Pathway
Tissue factor (TF) expressed in cancer cells has been linked to tumor-associated thrombosis, a major cause of mortality in malignancy. Hypoxia is a common feature of solid tumors and can upregulate TF. In this study, the effect of YC-1, a putative inhibitor of hypoxia-inducible factor-1α (HIF-1α), on hypoxia-induced TF expression was investigated in human lung cancer A549 cells. YC-1 selectively prevented hypoxia-induced TF expression and procoagulant activity without affecting the basal TF levels. Surprisingly, knockdown or pharmacological inhibition of HIF-1α failed to mimic YC-1′s effect on TF expression, suggesting other mechanisms are involved. NF-κB, a transcription factor for TF, and its upstream regulator p38, were activated by hypoxia exposure. Treatment of hypoxic A549 cells with YC-1 prevented the activation of both NF-κB and p38. Inhibition of p38 suppressed hypoxia-activated NF-κB, and inhibited TF expression and activity to similar levels as treatment with an NF-κB inhibitor. Furthermore, stimulation of p38 by anisomycin reversed the effects of YC-1. Taken together, our results suggest that YC-1 prevents hypoxia-induced TF in cancer cells by inhibiting the p38/NF-κB pathway, this is distinct from the conventional anticoagulants that systemically inhibit blood coagulation and may shed new light on approaches to treat tumor-associated thrombosis
Color Doppler Echocardiographic Study on the Incidence and Natural History of Early-Infancy Muscular Ventricular Septal Defect
Most small muscular ventricular septal defect (M-VSD) types have been diagnosed using color Doppler echocardiography. The purpose of this study was to understand the incidence of small M-VSD in the neonatal period and analyze the natural history of these M-VSDs.
Materials and Methods: All individuals in our study were neonates delivered at term who had a normal healthy appearance. Each accepted neonate had an examination with complete color Doppler echocardiography once before discharge. If the examination was confirmed for M-VSD, the study participants were then classified according to defect type. Further examination was arranged with color Doppler echocardiography at 1 month, 2 months, 4 months, 6 months, 9 months, and 12 months of age or until there was complete spontaneous closure.
Results: Among 2891 neonates, we found that 72 (24.9/1000) were diagnosed with M-VSD. Among this group, 38 were male and 34 were female. Only six infants were lost to follow-up. Fifty-four of the 66 infants (81.8%) had M-VSD closed spontaneously at 12 months’ follow-up. Significantly, 33 of 37 infants (89.2%) with mid-muscular type, the most common type of M-VSD, closed within the 1st year of life compared with apical type (17/24:70.8%). Four of the five infants (80%) had anterior type M-VSD closed. Infants with posterior type M-VSD were not seen during this study period.
Conclusion: Although the incidence of M-VSD was common in the neonatal period, there was also a high rate of spontaneous closure. Therefore, comparison of M-VSD appearance with the incidence of congenital heart disease in neonates had a decisive influence on analysis
CD40-mediated HIF-1α expression underlying microangiopathy in diabetic nerve pathology
To understand the pathology and molecular signatures of microangiopathy in diabetic neuropathy, we systemically and quantitatively examined the morphometry of microvascular and nerve pathologies of sural nerves. In the endoneurium of diabetic nerves, prominent microangiopathy was observed, as evidenced by reduced capillary luminal area, increased capillary basement membrane thickness and increased proportion of fibrin(+) blood vessels. Furthermore, capillary basement membrane thickness and the proportion of fibrin(+) blood vessels were correlated with small myelinated fiber density in diabetic nerves. In diabetic nerves, there was also significant macrophage and T cell infiltration, and cluster of differentiation 40 (CD40) expression was increased. The molecular alterations observed were upregulation of hypoxia-inducible factor-1α (HIF-1α), mitogen-activated protein kinase-activated protein kinase 2 (MK2; MAPKAPK2) and phosphatase and tensin homolog (PTEN). In addition, HIF-1α was correlated with small myelinated fiber density and capillary luminal area, while both MK2 and PTEN were correlated with capillary basement membrane thickness. The molecular cascades were further demonstrated and replicated in a cell model of microangiopathy on human umbilical vein endothelial cells (HUVECs) exposed to high-glucose medium by silencing of CD40, PTEN and HIF-1α in HUVECs using shRNA. These data clarified the hierarchy of the molecular cascades, i.e. upregulation of CD40 leading to HIF-1α expression in endothelium and nerve fibers. In conclusion, this study revealed the association of microangiopathy, thrombosis and inflammatory infiltrates with nerve degeneration in diabetic nerves, demonstrating that CD40 is a key molecule for the upregulation of HIF-1α and PTEN underlying the severity of microangiopathy
Selective cytotoxic eremophilane-type sesquiterpenes from Penicillium citreonigrum
One new eremophilane-type sesquiterpene (1, citreopenin) was isolated from Penicillium citreonigrum (HQ738282), and the structure was elucidated by a combination of spectroscopic data interpretation and single-crystal X-ray diffraction analysis using Cu Kα radiation (CCDC 1030588). Compound 1 showed weak activity against KB-VIN (IC(50) = 11.0 ± 0.156 μM), while the known compound 3 exhibited selective cytotoxicity against MDA-MB-231 triple-negative breast cancer (TNBC) (IC(50) = 5.42 ± 0.167 μM)
Respiratory Trajectory after Invasive Interventions for Patent Ductus Arteriosus of Preterm Infants
Invasive interventions have been conducted in preterm infants with significant patent ductus arteriosus (PDA) when medical treatment has failed, and methods of invasive intervention have been reported. Surgical ligation via lateral thoracotomy has been a well-established procedure for decades. Recently, transcatheter occlusion has been safely and feasibly applied to the premature population. However, little research has been conducted on the benefits of transcatheter occlusion in very-low-birth-weight (VLBW) infants compared to surgical ligation. This study compared transcatheter and surgical techniques in VLBW infants in terms of short-term respiratory outcomes. The medical records of 401 VLBW infants admitted to a tertiary hospital between September 2014 and January 2019 were retrospectively reviewed. Patients who were diagnosed with a congenital anomaly, a chromosomal anomaly, or congenital heart disease, except for an inter-atrial shunt, were excluded. The perinatal conditions, neonatal morbidities, periprocedural vital signs, and respiratory support trajectories were compared between the transcatheter-treated and surgically ligated group. A total of 31 eligible VLBW infants received invasive intervention: 14 were treated with transcatheter occlusion (Group A), and 17 infants were treated with surgical ligation (Group B). Respiratory outcomes were not statistically significant between the two groups, despite Group A showing a trend toward early improvement in post-intervention respiratory trajectory. In this small case study, a different trend in post-intervention respiratory trajectories was observed. Future research with larger case numbers should be conducted to address our preliminary observations in more detail