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1.
Open Forum Infect Dis ; 9(8): ofac390, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35991589

ABSTRACT

Background: Households are common places for spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We investigated factors associated with household transmission and acquisition of SARS-CoV-2. Methods: Households with children age <18 years were enrolled into prospective, longitudinal cohorts and followed from August 2020 to August 2021 in Utah, September 2020 to August 2021 in New York City, and November 2020 to October 2021 in Maryland. Participants self-collected nasal swabs weekly and with onset of acute illness. Swabs were tested for SARS-CoV-2 using reverse transcription polymerase chain reaction. We assessed factors associated with SARS-CoV-2 acquisition using a multilevel logistic regression adjusted for household size and clustering and SARS-CoV-2 transmission using a logistic regression adjusted for household size. Results: Among 2053 people (513 households) enrolled, 180 people (8.8%; in 76 households) tested positive for SARS-CoV-2. Compared with children age <12 years, the odds of acquiring infection were lower for adults age ≥18 years (adjusted odds ratio [aOR], 0.34; 95% CI, 0.14-0.87); however, this may reflect vaccination status, which protected against SARS-CoV-2 acquisition (aOR, 0.17; 95% CI, 0.03-0.91). The odds of onward transmission were similar between symptomatic and asymptomatic primary cases (aOR, 1.00; 95% CI, 0.35-2.93) and did not differ by age (12-17 years vs <12 years: aOR, 1.08; 95% CI, 0.20-5.62; ≥18 years vs <12 years: aOR, 1.70; 95% CI, 0.52-5.83). Conclusions: Adults had lower odds of acquiring SARS-CoV-2 compared with children, but this association might be influenced by coronavirus disease 2019 (COVID-19) vaccination, which was primarily available for adults and protective against infection. In contrast, all ages, regardless of symptoms and COVID-19 vaccination, had similar odds of transmitting SARS-CoV-2. Our findings underscore the importance of SARS-CoV-2 mitigation measures for persons of all ages.

2.
JAMA Pediatr ; 176(1): 59-67, 2022 01 01.
Article in English | MEDLINE | ID: mdl-34623377

ABSTRACT

Importance: Data about the risk of SARS-CoV-2 infection among children compared with adults are needed to inform COVID-19 risk communication and prevention strategies, including COVID-19 vaccination policies for children. Objective: To compare incidence rates and clinical characteristics of SARS-CoV-2 infection among adults and children and estimated household infection risks within a prospective household cohort. Design, Setting, and Participants: Households with at least 1 child aged 0 to 17 years in selected counties in Utah and New York City, New York, were eligible for enrollment. From September 2020 through April 2021, participants self-collected midturbinate nasal swabs for reverse transcription-polymerase chain reaction testing for SARS-CoV-2 and responded to symptom questionnaires each week. Participants also self-collected additional respiratory specimens with onset of COVID-19-like illness. For children unable to self-collect respiratory specimens, an adult caregiver collected the specimens. Main Outcomes and Measures: The primary outcome was incident cases of any SARS-CoV-2 infection, including asymptomatic and symptomatic infections. Additional measures were the asymptomatic fraction of infection calculated by dividing incidence rates of asymptomatic infection by rates of any infection, clinical characteristics of infection, and household infection risks. Primary outcomes were compared by participant age group. Results: A total of 1236 participants in 310 households participated in surveillance, including 176 participants (14%) who were aged 0 to 4 years, 313 (25%) aged 5 to 11 years, 163 (13%) aged 12 to 17 years, and 584 (47%) 18 years or older. Overall incidence rates of SARS-CoV-2 infection were 3.8 (95% CI, 2.4-5.9) and 7.7 (95% CI, 4.1-14.5) per 1000 person-weeks among the Utah and New York City cohorts, respectively. Site-adjusted incidence rates per 1000 person-weeks were similar by age group: 6.3 (95% CI, 3.6-11.0) for children 0 to 4 years, 4.4 (95% CI, 2.5-7.5) for children 5 to 11 years, 6.0 (95% CI, 3.0-11.7) for children 12 to 17 years, and 5.1 (95% CI, 3.3-7.8) for adults (≥18 years). The asymptomatic fractions of infection by age group were 52%, 50%, 45%, and 12% among individuals aged 0 to 4 years, 5 to 11 years, 12 to 17 years, and 18 years or older, respectively. Among 40 households with 1 or more SARS-CoV-2 infections, the mean risk of SARS-CoV-2 infection among all enrolled household members was 52% (range, 11%-100%), with higher risks in New York City compared with Utah (80% [95% CI, 64%-91%] vs 44% [95% CI, 36%-53%]; P < .001). Conclusions and Relevance: In this study, children had similar incidence rates of SARS-CoV-2 infection compared with adults, but a larger proportion of infections among children were asymptomatic.

3.
Front Neurosci ; 14: 879, 2020.
Article in English | MEDLINE | ID: mdl-32973433

ABSTRACT

Nematode parasitosis causes significant mortality and morbidity in humans and considerable losses in livestock and domestic animals. The acquisition of resistance to current anthelmintic drugs has prompted the search for new compounds for which the free-living nematode Caenorhabditis elegans has emerged as a valuable platform. We have previously synthetized a small library of oxygenated tricyclic compounds and determined that dibenzo[b,e]oxepin-11(6H)-one (doxepinone) inhibits C. elegans motility. Because doxepinone shows potential anthelmintic activity, we explored its behavioral effects and deciphered its target site and mechanism of action on C. elegans. Doxepinone reduces swimming rate, induces paralysis, and decreases the rate of pharyngeal pumping required for feeding, indicating a marked anthelmintic activity. To identify the main drug targets, we performed an in vivo screening of selected strains carrying mutations in Cys-loop receptors involved in worm locomotion for determining resistance to doxepinone effects. A mutant strain that lacks subunit genes of the invertebrate glutamate-gated chloride channels (GluCl), which are targets of the widely used antiparasitic ivermectin (IVM), is resistant to doxepinone effects. To unravel the molecular mechanism, we measured whole-cell currents from GluClα1/ß receptors expressed in mammalian cells. Glutamate elicits macroscopic currents whereas no responses are elicited by doxepinone, indicating that it is not an agonist of GluCls. Preincubation of the cell with doxepinone produces a statistically significant decrease of the decay time constant and net charge of glutamate-elicited currents, indicating that it inhibits GluCls, which contrasts to IVM molecular actions. Thus, we identify doxepinone as an attractive scaffold with promising anthelmintic activity and propose the inhibition of GluCls as a potential anthelmintic mechanism of action.

4.
Comput Biol Chem ; 83: 107101, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31442708

ABSTRACT

Lupane-type triterpenoids have shown a potential effect against neurodegenerative disorders. Alzheimer's disease, one of the common neurodegenerative disease, is evident by the accumulation of amyloid-beta (Aß) plaque in the extracellular regions of the brain. ß-site amyloid precursor protein cleaving enzyme 1 (BACE1) is a key enzyme for the Aß formation viathe cleavage of amyloid precursor protein (APP). Therefore, to find the potent BACE1 inhibitors and furthermore to explore the role of the functional group responsible for the strong BACE1 inhibitory activity, we synthesized a series of triterpenoids with lupane skeleton starting from the natural compounds calenduladiol and lupeol. Compound 1 revealed a potent competitive BACE1 inhibitory activity (IC50 = 16.77 ±â€¯1.16 µM; Ki = 19.38). Furthermore, the molecular docking simulation revealed the importance of Tyr198 residue along with the other hydrophobic interactions for the strong affinity of 1‒BACE1 complex. To sum up, our results demonstrated the importance of carbonyl moiety at 3 and 16 position of lupane-type triterpenoid over the hydroxyl group at the same position.


Subject(s)
Amyloid Precursor Protein Secretases/antagonists & inhibitors , Aspartic Acid Endopeptidases/antagonists & inhibitors , Enzyme Inhibitors/pharmacology , Triterpenes/pharmacology , Amyloid Precursor Protein Secretases/metabolism , Aspartic Acid Endopeptidases/metabolism , Crystallography, X-Ray , Enzyme Inhibitors/chemistry , Humans , Kinetics , Models, Molecular , Triterpenes/chemistry
5.
Anticancer Res ; 39(7): 3835-3845, 2019 Jul.
Article in English | MEDLINE | ID: mdl-31262911

ABSTRACT

BACKGROUND/AIM: This study examined the potential role of natural triterpenoids lupeol, calenduladiol and heliantriol B2, and a set of 19 derivatives, as antiproliferative and antimetastatic agents against prostate cancer cells. MATERIALS AND METHODS: Natural triterpenoids were isolated from Chuqiraga erinaceae. Analogs were obtained by transformations of lupeol and calenduladiol. The effects of compounds on PC-3 and LNCaP cells were determined using the MTT assay. Compounds with half-maximal inhibitory concentration <70 µM were evaluated as antimetastatic agents by a wound-healing assay. RESULTS: Lupeol-3ß-sulfate, a new semisynthetic lupane, was the most active compound. In general, sulfated derivatives displayed higher activity than the lead against both cell lines. A new analog, calenduladiol-3ß-monosulfate, inhibited the migration of PC-3 cells; heliantriol B2 and 3ß-aminolupane inhibited the migration of LNCaP cells in a concentration-dependent manner. CONCLUSION: Our study provides novel agents with cytotoxic effects on prostate cancer cells, which may represent a potential new therapeutic approach for prostate cancer.


Subject(s)
Antineoplastic Agents/pharmacology , Prostatic Neoplasms/drug therapy , Triterpenes/pharmacology , Cell Line, Tumor , Cell Proliferation/drug effects , Humans , Male , Wound Healing/drug effects
6.
Bioorg Chem ; 79: 301-309, 2018 09.
Article in English | MEDLINE | ID: mdl-29793143

ABSTRACT

A set of triterpenoids with different grades of oxidation in the lupane skeleton were prepared and evaluated as cholinesterase inhibitors. Allylic oxidation with selenium oxide and Jones's oxidation were employed to obtain mono-, di- and tri-oxolupanes, starting from calenduladiol (1) and lupeol (3). All the derivatives showed a selective inhibition of butyrylcholinesterase over acetylcholinesterase (BChE vs. AChE). A kinetic study proved that compounds 2 and 9, the more potent inhibitors of the series, act as competitive inhibitors. Molecular modeling was used to understand their interaction with BChE, the role of carbonyl at C-16 and the selectivity towards this enzyme over AChE. These results indicate that oxidation at C-16 of the lupane skeleton is a key transformation in order to improve the cholinesterase inhibition of these compounds.


Subject(s)
Butyrylcholinesterase/metabolism , Cholinesterase Inhibitors/pharmacology , Triterpenes/pharmacology , Acetylcholinesterase/chemistry , Acetylcholinesterase/metabolism , Animals , Butyrylcholinesterase/chemistry , Cholinesterase Inhibitors/chemical synthesis , Cholinesterase Inhibitors/chemistry , Dose-Response Relationship, Drug , Humans , Molecular Docking Simulation , Molecular Structure , Oxidation-Reduction , Structure-Activity Relationship , Torpedo , Triterpenes/chemical synthesis , Triterpenes/chemistry
7.
Bioorg Med Chem ; 22(13): 3341-50, 2014 Jul 01.
Article in English | MEDLINE | ID: mdl-24835788

ABSTRACT

A set of twenty one lupane derivatives (2-22) was prepared from the natural triterpenoid calenduladiol (1) by transformations on the hydroxyl groups at C-3 and C-16, and also on the isopropenyl moiety. The derivatives were tested for their inhibitory activity against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) and some structure-activity relationships were outlined with the aid of enzyme kinetic studies and docking modelization. The most active compound resulted to be 3,16,30-trioxolup-20(29)-ene (22), with an IC50 value of 21.5µM for butyrylcholinesterase, which revealed a selective inhibitor profile towards this enzyme.


Subject(s)
Acetylcholinesterase/metabolism , Butyrylcholinesterase/metabolism , Cholinesterase Inhibitors/pharmacology , Triterpenes/pharmacology , Animals , Butyrylcholinesterase/blood , Cholinesterase Inhibitors/chemical synthesis , Cholinesterase Inhibitors/chemistry , Dose-Response Relationship, Drug , Eels , Horses , Kinetics , Models, Molecular , Molecular Conformation , Structure-Activity Relationship , Triterpenes/chemical synthesis , Triterpenes/chemistry
8.
Curr Neuropharmacol ; 11(4): 388-413, 2013 Jul.
Article in English | MEDLINE | ID: mdl-24381530

ABSTRACT

As acetylcholinesterase (AChE) inhibitors are an important therapeutic strategy in Alzheimer's disease, efforts are being made in search of new molecules with anti-AChE activity. The fact that naturally-occurring compounds from plants are considered to be a potential source of new inhibitors has led to the discovery of an important number of secondary metabolites and plant extracts with the ability of inhibiting the enzyme AChE, which, according to the cholinergic hypothesis, increases the levels of the neurotransmitter acetylcholine in the brain, thus improving cholinergic functions in patients with Alzheimer's disease and alleviating the symptoms of this neurological disorder. This review summarizes a total of 128 studies which correspond to the most relevant research work published during 2006-2012 (1st semester) on plant-derived compounds, plant extracts and essential oils found to elicit AChE inhibition.

9.
Planta Med ; 76(6): 607-10, 2010 Apr.
Article in English | MEDLINE | ID: mdl-19918718

ABSTRACT

A bioactivity-guided approach was taken to identify the acetylcholinesterase (AChE) inhibitory agents in the ethanolic extract of Chuquiraga erinacea D. Don. subsp. erinacea leaves using a bioautographic method. This permitted the isolation of the pentacyclic triterpenes calenduladiol (1), faradiol (2), heliantriol B2 (3), lupeol (4), and a mixture of alpha-and beta-amyrin ( 5A and 5B) as active constituents. Pseudotaraxasterol (6) and taraxasterol (7) were also isolated from this extract and showed no activity at the same analytical conditions. Compound 1 showed the highest AChE inhibitory activity with 31.2 % of inhibition at 0.5 mM. Looking forward to improve the water solubility of the active compounds, the sodium sulfate ester of 1 was prepared by reaction with the (CH3)3N.SO3 complex. The semisynthetic derivative disodium calenduladiol disulfate (8) elicited higher AChE inhibition than 1 with 94.1 % of inhibition at 0.5 mM (IC (50) = 0.190 +/- 0.003 mM). Compounds 1, 2, 3, 5, 6, and 7 are reported here for the first time in C. erinacea. This is the first report of AChE inhibition from calenduladiol (1) as well as from a sulfate derived from a natural product.


Subject(s)
Asteraceae/chemistry , Cholinesterase Inhibitors/chemistry , Cholinesterase Inhibitors/pharmacology , Triterpenes/chemistry , Triterpenes/pharmacology , Molecular Structure
10.
Arq. neuropsiquiatr ; 47(1): 72-5, mar. 1989. ilus
Article in English | LILACS | ID: lil-69655

ABSTRACT

A literatura registra 8 casos publicados de afasia lentamente progressiva, dois dos quais progrediram em período de anos para demência generalizada. Tomografia por emissäo de pósitrons demonstrou metabolismo diminuído de glicose na regiäo peri-silviana esquerda em dois casos. Descrevemos o caso de um paciente que teve afasia lentamente progressiva e desenvolveu demência generalizada de tipo Alzheimer, 7 anos após a apresentaçäo inicial. Näo foi encontrada evidência clínica ou laboratorial de doença concomitante. Tomografia computadorizada mostrou atrofia generalizada mais marcada na regiäo peri-silviana esquerda tardiamente no processo, quando EEG mostrou lentificaçäo generalizada, mais claramente na mesma área. Afasia lentamente progressiva da idade avançada deve ser considerada entidade em separado até que estudos elucidem sua relaçäo com demência de Alzheimer


Subject(s)
Aged , Humans , Male , Alzheimer Disease/diagnosis , Aphasia/diagnosis , Alzheimer Disease/physiopathology , Aphasia/physiopathology , Diagnosis, Differential
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