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1.
Indian J Med Microbiol ; 48: 100549, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38395257

RESUMO

PURPOSE: An acute conjunctivitis outbreak was investigated at a residential school in Naharlagun, Arunachal Pradesh, Northeast India, in July 2023. We aimed to identify the etiological agent and assess any complications in follow-up cases. METHODS: We used a structured questionnaire to record clinical findings and followed up with cases one-month post-conjunctivitis. Sixty-one cases were examined and eight conjunctival and oropharyngeal swab samples were collected after obtaining informed consent from guardians/school authorities. We screened for 33 viral and bacterial pathogens using an IVD-approved Real-time PCR assay. Further, the samples were subjected to nucleic acid sequencing. RESULTS: Among 465 screened students and staff, 80 individuals (approximately 17.2%) showed acute hemorrhagic conjunctivitis symptoms among which 61 cases were available for clinical examination. We identified the Enterovirus responsible by targeted sequencing using next-generation sequencing. The etiological agent was found to be Coxsackievirus A24, a member of Enterovirus C, in seven out of eight samples subjected to sequencing. Common symptoms included conjunctival hyperemia and foreign body sensation (100%), bilateral eye involvement (73.8%), eye pain (70%), watery discharge (49.2%), and eyelid swelling (38%). Only 6.5% had purulent discharge. Most cases resolved within 5-6 days, with only 9.8% reporting abdominal symptoms post-conjunctivitis. No serious complications occurred within one month. Throat swabs aided in diagnosing enterovirus infections alongside eye swabs. CONCLUSIONS: The outbreak of acute conjunctivitis was caused by Coxsackievirus A24, a member of Enterovirus C. Cases resolved spontaneously within 6-7 days, with no severe complications. Collecting oropharyngeal swabs alongside conjunctival swabs could improve enteroviral conjunctivitis diagnosis.


Assuntos
Conjuntivite Hemorrágica Aguda , Surtos de Doenças , Enterovirus Humano C , Humanos , Índia/epidemiologia , Conjuntivite Hemorrágica Aguda/epidemiologia , Conjuntivite Hemorrágica Aguda/virologia , Masculino , Feminino , Enterovirus Humano C/isolamento & purificação , Enterovirus Humano C/genética , Criança , Adolescente , Instituições Acadêmicas , Adulto , Adulto Jovem , Infecções por Coxsackievirus/epidemiologia , Infecções por Coxsackievirus/virologia , Infecções por Coxsackievirus/diagnóstico
2.
Insects ; 15(1)2024 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-38276822

RESUMO

Tetranychus urticae is a highly polyphagous and global pest. Spider mites primarily feed on the underside of leaves, resulting in decreased photosynthesis, nutritional loss, and the development of chlorotic patches. We investigated the life tables of the two-spotted spider mite T. urticae on fungal endophyte Beauveria bassiana colonized and untreated plants of the common Phaseolus vulgaris L., a bean plant. Based on the age-stage, two-sex life table theory, data were evaluated. The mites raised on untreated plants had protonymphs, deutonymphs, and total pre-adult stage durations that were considerably shorter (1.76, 2.14, and 9.77 d, respectively) than the mites raised on plants that had been colonized (2.02, 2.45, and 10.49 d, respectively). The fecundity (F) varied from 28.01 eggs per female of colonized plants to 57.67 eggs per female of endophyte-untreated plants. The net reproductive rate (R0) in the plants with and without endophytes was 19.26 and 42.53 brood, respectively. The untreated plants had an intrinsic rate of increase (rm) of 0.245 days as opposed to the colonized plants, which had an r of 0.196 days and a finite rate of increase (λ) (1.27 and 1.21, respectively). Population forecasts based on a two-sex, age-stage life table demonstrated the dynamism and variability of the stage structure. Furthermore, the colonization of B. bassiana had a negative impact on the growth and development of T. urticae. It lowered the adult mite life span, female fecundity, net reproduction rate, and intrinsic growth rate. We propose that future research should better use entomopathogenic fungal endophytes to understand host plant resistance strategies in integrated pest management.

3.
J Biomol Struct Dyn ; : 1-16, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38014451

RESUMO

Overexpression of HDAC 2 promotes cell proliferation in ovarian cancer. HDAC 2 is involved in chromatin remodeling, transcriptional repression, and the formation of condensed chromatin structures. Targeting HDAC 2 presents a promising therapeutic approach for correcting cancer-associated epigenetic abnormalities. Consequently, HDAC 2 inhibitors have evolved as an attractive class of anti-cancer agents. This work intended to investigate the anti-cancer abilities and underlying molecular mechanisms of Rhamnetin in human epithelial ovarian carcinoma cells (SKOV3), which remain largely unexplored. We employed various in vitro methods, including MTT, apoptosis study, cell cycle analysis, fluorescence microscopy imaging, and in vitro enzymatic HDAC 2 protein inhibition, to examine the chemotherapeutic sensitivity of Rhamnetin in SKOV3 cells. Additionally, we conducted in silico studies using molecular docking, MD simulation, MM-GBSA, DFT, and pharmacokinetic analysis to investigate the binding interaction mechanism within Rhamnetin and HDAC 2, alongside the compound's prospective as a lead candidate. The in vitro assay confirmed the cytotoxic effects of Rhamnetin on SKOV3 cells, through its inhibition of HDAC 2 activity. Rhamnetin, a nutraceutical flavonoid, halted at the G1 phase of the cell cycle and triggered apoptosis in SKOV3 cells. Furthermore, computational studies provided additional evidence of its stable binding to the HDAC 2 protein's binding site cavity. Based on our findings, we conclude that Rhamnetin effectively promotes apoptosis and mitigates the proliferation of SKOV3 cells through HDAC 2 inhibition. These results highlight Rhamnetin as a potential lead compound, opening a new therapeutic strategy for human epithelial ovarian cancer.Communicated by Ramaswamy H. Sarma.

4.
Science ; 382(6668): 325-329, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37856595

RESUMO

Benzylic stereogenic centers are ubiquitous in natural products and pharmaceuticals. A potentially general, though challenging, approach toward their selective creation would be asymmetric unimolecular nucleophilic substitution (SN1) reactions that proceed through highly reactive benzylic cations. We now report a broadly applicable solution to this problem by identifying chiral counteranions that pair with secondary benzylic cations to engage in catalytic asymmetric C-C, C-O, and C-N bond-forming reactions with excellent enantioselectivity. The critical cationic intermediate can be accessed from different precursors via Lewis- or Brønsted acid catalysis. Key to our strategy is the use of only weakly basic, confined counteranions that are posited to prolong the lifetime of the carbocation, thereby avoiding nonproductive deprotonation pathways to the corresponding styrene.

5.
Parkinsonism Relat Disord ; 115: 105799, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37633805

RESUMO

Parkinson's disease (PD) is a common neurodegenerative disorder characterized by the progressive degeneration of dopaminergic neurons in the substantia nigra pars compacta. Although the exact etiology of PD remains elusive, growing evidence suggests a complex interplay of genetic, environmental, and lifestyle factors in its development. Despite advances in pharmacological interventions, current treatments primarily focus on managing symptoms rather than altering the disease's underlying course. In recent years, natural phytocompounds have emerged as a promising avenue for PD management. Phytochemicals derived from plants, such as phenolic acids, flavones, phenols, flavonoids, polyphenols, saponins, terpenes, alkaloids, and amino acids, have been extensively studied for their potential neuroprotective effects. These bioactive compounds possess a wide range of therapeutic properties, including antioxidant, anti-inflammatory, anti-apoptotic, and anti-aggregation activities, which may counteract the neurodegenerative processes in PD. This comprehensive review delves into the pathophysiology of PD, with a specific focus on the roles of oxidative stress, mitochondrial dysfunction, and protein malfunction in disease pathogenesis. The review collates a wealth of evidence from preclinical studies and in vitro experiments, highlighting the potential of various phytochemicals in attenuating dopaminergic neuron degeneration, reducing α-synuclein aggregation, and modulating neuroinflammatory responses. Prominent among the natural compounds studied are curcumin, resveratrol, coenzyme Q10, and omega-3 fatty acids, which have demonstrated neuroprotective effects in experimental models of PD. Additionally, flavonoids like baicalein, luteolin, quercetin, and nobiletin, and alkaloids such as berberine and physostigmine, show promise in mitigating PD-associated pathologies. This review emphasizes the need for further research through controlled clinical trials to establish the safety and efficacy of these natural compounds in PD management. Although preclinical evidence is compelling, the translation of these findings into effective therapies for PD necessitates robust clinical investigation. Rigorous evaluation of pharmacokinetics, bioavailability, and potential drug interactions is imperative to pave the way for evidence-based treatment strategies. With the rising interest in natural alternatives and the potential for synergistic effects with conventional therapies, this review serves as a comprehensive resource for pharmaceutical industries, researchers, and clinicians seeking novel therapeutic approaches to combat PD. Harnessing the therapeutic potential of these natural phytocompounds may hold the key to improving the quality of life for PD patients and moving towards disease-modifying therapies in the future.


Assuntos
Alcaloides , Fármacos Neuroprotetores , Doença de Parkinson , Humanos , Doença de Parkinson/patologia , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Qualidade de Vida , Flavonoides/farmacologia , Flavonoides/uso terapêutico , Neurônios Dopaminérgicos/patologia , Alcaloides/farmacologia , Alcaloides/uso terapêutico , Gerenciamento Clínico
6.
Science ; 379(6631): 494-499, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36656920

RESUMO

Photoredox catalysis enables distinctive and broadly applicable chemical reactions, but controlling their selectivity has proven to be difficult. The pursuit of enantioselectivity is a particularly daunting challenge, arguably because of the high energy of the activated radical (ion) intermediates, and previous approaches have invariably required pairing of the photoredox catalytic cycle with an additional activation mode for asymmetric induction. A potential solution for photoredox reactions proceeding via radical ions would be catalytic pairing with enantiopure counterions. However, although attempts toward this approach have been described, high selectivity has not yet been accomplished. Here we report a potentially general solution to radical cation-based asymmetric photoredox catalysis. We describe organic salts, featuring confined imidodiphosphorimidate counteranions that catalyze highly enantioselective [2+2]-cross cycloadditions of styrenes.

7.
Nature ; 605(7908): 84-89, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35508776

RESUMO

Enzymatic stereoselectivity has typically been unrivalled by most chemical catalysts, especially in the conversion of small substrates. According to the 'lock-and-key theory'1,2, enzymes have confined active sites to accommodate their specific reacting substrates, a feature that is typically absent from chemical catalysts. An interesting case in this context is the formation of cyanohydrins from ketones and HCN, as this reaction can be catalysed by various classes of catalysts, including biological, inorganic and organic ones3-7. We now report the development of broadly applicable confined organocatalysts for the highly enantioselective cyanosilylation of aromatic and aliphatic ketones, including the challenging 2-butanone. The selectivity (98:2 enantiomeric ratio (e.r.)) obtained towards its pharmaceutically relevant product is unmatched by any other catalyst class, including engineered biocatalysts. Our results indicate that confined chemical catalysts can be designed that are as selective as enzymes in converting small, unbiased substrates, while still providing a broad scope.


Assuntos
Cetonas , Catálise , Cetonas/química , Estereoisomerismo
8.
Viral Immunol ; 35(4): 338-344, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35580072

RESUMO

Persistence of hepatitis B virus (HBV) infection leading to chronic infection and its sequalae is responsible for over half a million deaths worldwide. The reason for persistence of chronic hepatitis B (CHB) infection is still not clearly understood. An attempt was made to understand the role of immune regulatory genes in CHB in comparison to spontaneously cleared HBV infection. Relative gene expression of 26 genes involved in innate immunity were studied using Real-Time Polymerase Chain Reaction Array. A total of 679 subjects from three different geographical regions of Northeast India (Assam, Arunachal Pradesh, and Tripura) were included in this case-control study. The cases were subdivided into CHB cases with HBeAg(+)(72), CHB with HBeAg(-)(278), spontaneously cleared controls (88), and healthy controls (228). Overall, 28.3% of the subjects had previous exposure with HBV, while 28.6% had protective antibodies IgG/IgM against HBV. There was a statistically higher number of CHB in men (66.4%) compared to women (33.6%) (p = 0.0001). Proto-oncogene FOS has been found to be moderately upregulated in CHB with HBeAg +ve (2.3-fold) and significantly upregulated (4.1-fold upregulation) in hepatocellular carcinoma. Further, FOXP3 was found to be significantly upregulated (3.0-fold, p = 0.01) in CHB with HBeAg (+) compared to spontaneously cleared HBV infection. In conclusion, CHB with HBeAg positivity was found to have disrupted immune response with upregulation of FOS and FOXP3. Thus, early induction of HBeAg seroconversion with interferon-based therapy or oral nucleos(t)ide analogs along with FOS inhibitors can have important clinical implications in the management of CHB and preventing cirrhosis and HCC.


Assuntos
Fatores de Transcrição Forkhead , Hepatite B Crônica , Antivirais/uso terapêutico , Estudos de Casos e Controles , Feminino , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/imunologia , Genes Reguladores , Antígenos E da Hepatite B/imunologia , Vírus da Hepatite B/imunologia , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/genética , Hepatite B Crônica/imunologia , Humanos , Imunidade Inata , Masculino , Proteínas Proto-Oncogênicas c-fos/genética , Proteínas Proto-Oncogênicas c-fos/imunologia
9.
J Genet ; 1002021.
Artigo em Inglês | MEDLINE | ID: mdl-34825657

RESUMO

Rhinoceros unicornis, also known as the greater one-horned rhinoceros (GoHR), is a vulnerable wildlife species found in the Indian subcontinent with an estimated global population of 3582, of which an estimated 2995 resides in India. The Kaziranga National Park of Assam is the home to ~80.56% of the GoH population in India. Recent advances in genetics and microbial studies underscored the importance of gut microbial symbiosis as a crucial factor for host metabolic health and environmental interaction, particularly for higher mammals. Alteration of the normal microbiome can also be an indicator of chronic disease and infection. Freshly voided dung samples from nine dung heaps of free ranging or wild GoH rhinoceros were collected from Kaziranga National Park for mapping the gut microbial architecture through 16S-metagenomic approach. In our sample, the GoH gut harbours 168.8±12.55 (SE) bacteria-specific OTUs belonging to 21 phyla of which the gram-negative Proteobacteria is the most abundant phyla. Other abundant phylas found in the GoH gut are Firmicutes and Bacteroidetes. Although the GoH rhinoceros gut can utilize fibrous plant by microbial fermentation, the aerobic, nonfermenting Acinetobacter (20.7%), Stenotrophomonas (17.8%) and Brevundimonas (9.1%) constitute about 50% of all identified genus. Functional prediction of the GoH microbiome reveals that>50% of the bacteria present are involved in metabolism followed by cellular processes and information processing. A significant proportion (>1%) are associated with different diseases. In summary, our study characterized bacterial communities of nine wild GoH to identify some unique features and its implication in disease and survival of GoH.


Assuntos
Microbioma Gastrointestinal , Perissodáctilos/microbiologia , Animais , Animais Selvagens/microbiologia , Bactérias/classificação , Bactérias/isolamento & purificação , Fezes/microbiologia , Fungos/classificação , Fungos/isolamento & purificação , Sequenciamento de Nucleotídeos em Larga Escala/veterinária , Índia
10.
J Am Chem Soc ; 143(36): 14835-14844, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34478297

RESUMO

We have designed and realized an efficient and operationally simple single-flask synthesis of imidodiphosphate-based Brønsted acids. The methodology proceeds via consecutive chloride substitutions of hexachlorobisphosphazonium salts, providing rapid access to imidodiphosphates (IDP), iminoimidodiphosphates (iIDP), and imidodiphosphorimidates (IDPi). These privileged acid catalysts feature a broad acidity range (pKa from ∼11 to <2 in MeCN) and a readily tunable confined active site. Our approach enables access to previously elusive catalyst scaffolds with particularly high structural confinement, one of which catalyzes the first highly enantioselective (>95:5 er) sulfoxidation of methyl n-propyl sulfide. Furthermore, the methodology delivers a novel, rationally designed super acidic catalyst motif, imidodiphosphorbis(iminosulfonylimino)imidate (IDPii), the extreme reactivity of which exceeds commonly employed super-Brønsted acids, such as trifluoromethanesulfonic acid. The unique reactivity of one such IDPii catalyst has been demonstrated in the first α-methylation of a silyl ketene acetal with methanol as the electrophilic alkylating reagent.

11.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-21258346

RESUMO

It is crucial to know whether a single dose of vaccine against SARS-CoV-2 is sufficient to elicit immune response in previously infected people in India. A total of 121 participants (baseline seropositive 46 and seronegative 75) were included to study the immune response to ChAdOx1-nCOV (Covishield) vaccine in previously infected or uninfected people. IgG antibodies were estimated at three different time intervals, i.e. pre-vaccination, 25-35 days post 1st vaccination and 25-35 days post 2nd vaccination. The IgG antibody titre was significantly high among previous seropositive subjects with single dose of vaccine compared to seronegative group with both doses of vaccine respectively (4.59{+/-}1.04 vs 3.08{+/-}1.22, p-value: <0.0001). In conclusion, a single dose of Covishield(R) vaccine might be sufficient to induce an effective immune responsein subjects with prior SARS-CoV2 infection. Stratifying vacinees based on their SARS-CoV2 IgG antibody titre before vaccination would help in meeting the increasing vaccine demand and could be effective to circumvent further wave of the pandemic in India.

12.
Indian Heart J ; 72(5): 398-402, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33189201

RESUMO

OBJECTIVE: Hypertension is a potential risk factor for cardiovascular diseases. With increasing age there is differential rise of systolic and diastolic blood pressure leading to development of various hypertension subtypes which have its own clinical implications. Present study assessed distribution and risk factors of hypertensive subtypes in the hill tribe of Mizoram. METHODS: The present study was a community-based cross-sectional study carried out in Aizawl, Mizoram representing both rural (fourteen villages) and urban (six wards) population and which were selected by PPS method. Individuals aged 18 years and above providing informed verbal consent were included for collection of sociodemographic and clinical data including blood pressure. Of the total 12,313 subjects (Urban: 5853, Rural: 6460) & (Male: 5459, Female: 6854) surveyed, 549 hypertensive subjects who were under antihypertensive treatment were excluded. Hypertension subtype was defined as per standard guidelines. RESULTS: Out of 11,764 study individuals, 88.03% (CI: 87.43-88.61) were normotensive and 11.97% (CI: 11.39-12.57) individuals were hypertensive. Prevalence of ISH, IDH and SDH were 241(2.05%), 403 (3.43%) and 764 (6.49%) respectively. Older age, unmarried participants, physical inactivity and obesity are found to be associated with ISH. Male gender, older age, higher educational status, physical inactivity, consumption of extra salt, alcohol consumption, use of tuibur and high BMI were significantly associated with SDH. CONCLUSIONS: The overall prevalence of hypertension with its subtypes specifically isolated systolic hypertension are low in this hill tribe of Mizoram. It is the right time for initiating intervention programme to modify the risk factors associated with hypertension.


Assuntos
Pressão Sanguínea/fisiologia , Hipertensão/epidemiologia , Medição de Risco/métodos , População Rural , Adulto , Estudos Transversais , Feminino , Humanos , Hipertensão/fisiopatologia , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco
13.
Toxicon ; 188: 39-47, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33058930

RESUMO

Entomopathogenic fungi (EPF) produce multiple mycotoxins, which play an essential role in improving fungal pathogenesis and virulence. To characterize various mycotoxins from the crude methanol extract of Cordyceps fumosorosea, a major EPF against various insect pests, we performed ultra-performance liquid chromatography coupled to quadrupole time of flight mass spectrometer (UPLC-QTOF MS) technique, and all compounds were identified through molecular mass and formulae. Bassianolide was assessed against the nymphs and adults of Diaphorina citri reared on healthy and Huánglóngbìng (HLB)-diseased Citrus spp. Plants under laboratory conditions. Overall, 17 compounds were identified from the fungal extract and categorized into three groups, i.e. (1) alkaloids (Isariotins A-C), (2) peptides (Bassianolide, Beauverolides, Beauvericin A, Isaridins and Destruxin E) and (3) polyketide (Tenuipyrone). The detected beauverolides (B, C, F, I, Ja) from C. fumosorosea were novel mycotoxins, and their detection intensity was the highest in the fungal extract. Furthermore, bassianolide caused more than 70% and 80% mortality of D. citri nymphs and adults after two days of application, respectively. After three days of chemical application, all nymphal and adult populations of D. citri were killed by bassianolide. However, the mortality rates of both populations, nymphs and adults, were higher on HLB-diseased plants as compared to healthy plants.


Assuntos
Citrus , Cordyceps , Hemípteros/efeitos dos fármacos , Micotoxinas , Animais , Hemípteros/fisiologia , Ninfa , Doenças das Plantas , Policetídeos , Virulência
14.
Nat Chem ; 12(12): 1174-1179, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32989271

RESUMO

Carbocations can be categorized into classical carbenium ions and non-classical carbonium ions. These intermediates are ubiquitous in reactions of both fundamental and practical relevance, finding application in the petroleum industry as well as the discovery of new drugs and materials. Conveying stereochemical information to carbocations is therefore of interest to a range of chemical fields. While previous studies targeted systems proceeding through classical ions, enantiocontrol over their non-classical counterparts has remained unprecedented. Here we show that strong and confined chiral acids catalyse enantioselective reactions via the non-classical 2-norbornyl cation. This reactive intermediate is generated from structurally different precursors by leveraging the reactivity of various functional groups to ultimately deliver the same enantioenriched product. Our work demonstrates that tailored catalysts can act as suitable hosts for simple, non-functionalized carbocations via a network of non-covalent interactions. We anticipate that the methods described herein will provide catalytic accessibility to valuable carbocation systems.

15.
Angew Chem Int Ed Engl ; 59(46): 20485-20488, 2020 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-32621795

RESUMO

We disclose a new Brønsted acid promoted quinoline synthesis, proceeding via homo-diaza-Cope rearrangement of N-aryl-N'-cyclopropyl hydrazines. Our strategy can be considered a homologation of Fischer's classical indole synthesis and delivers 6-membered N-heterocycles, including previously inaccessible pyridine derivatives. This approach can also be used as a pyridannulation methodology toward constructing polycyclic polyheteroaromatics. A computational analysis has been employed to probe plausible activation modes and to interrogate the role of the catalyst.

16.
Angew Chem Int Ed Engl ; 59(30): 12347-12351, 2020 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-32159921

RESUMO

We describe a highly enantioselective Diels-Alder reaction of cross-conjugated cyclohexadienones with cyclopentadiene, in which five stereocenters are effectively controlled by a strongly acidic and confined imidodiphosphorimidate catalyst. Our approach provides tricyclic products in excellent stereoselectivity. We also report methods to convert the obtained products into useful intermediates and a computational study that aids in gaining deeper insight into the reaction mechanism and origin of stereoselectivity.

17.
J Fungi (Basel) ; 6(1)2020 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-32106557

RESUMO

The inoculation methods, the fungal strains, and several other factors are known to influent the success of fungal entomopathogens colonization in plants. The physiological status of the plant could also be another determinant. In the present study, the ability of three strains of Beauveria bassiana and one strain of Metarhizium anisopliae to successfully colonize Citrus limon plants and the influence of seedling age on endophytic colonization success was examined. Three, 4, and 6 months old seedlings were inoculated with 10 mL of 1 × 108 conidial·mL-1 suspensions of each of the four fungal strains via foliar spraying. All fungal strains successfully colonized citrus seedlings and were sustained up to 2 months in colonized plants irrespective of the seedling age, with differences in the mean percentage colonization recorded at various post-inoculation periods among the fungal strains. The highest percent endophytic fungi recovery rate was recorded in the 3 months old seedlings, where fungal mycelia of inoculated fungi were successfully re-isolated from 65.6% of the untreated newly developed leaf and stem tissues. One strain of B. bassiana, BB Fafu-12, significantly improved seedling height and leaf number. The study demonstrates the influence of seedling age on B. bassiana and M. anisopliae successful colonization in the citrus plant.

18.
Theory Biosci ; 139(2): 145-151, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31673876

RESUMO

Topological features evolved from genetic operators in the recombination space play a crucial role in the course of evolution. Different crossover models generated in a recombination space can be structured by pretopological space. This paper deals with several types of connectedness properties of recombination space in three different cases of unequal crossover of recombination space structured as pretopology. It is shown that unrestricted unequal crossover is one-sidedly connected and consequently hyper-connected, apo-connected and connected as well. Restricted unequal crossover is hyper-connected and connected. Unequal sister chromatid exchange is connected.


Assuntos
Genótipo , Meiose , Mutação , Recombinação Genética , Troca de Cromátide Irmã , Algoritmos , Genoma , Modelos Genéticos
19.
Saudi J Biol Sci ; 26(7): 1695-1703, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31762646

RESUMO

Propolis is a natural substance collected by honey bees from various plants such as, poplar, palm, pine, conifer secretions, gums, resins, mucilage and leaf buds. It is collected and brought very painstakingly by honey bees to be used for sealing cracks and crevices occurring in their hives. Originally, it as an antiseptic meant for preventing bee-hive from microbial infections along with preventing decomposition of intruders. Additionally, propolis has been used in folk medicine for centuries. The biological characteristics of propolis depend upon its chemical composition, plant sources, geographical zone and seasons. More than 300 compounds have been identified in propolis such as, phenolic compounds, aromatic acids, essential oils, waxes and amino acids. Many scientific articles are published every year in different international journals, and several groups of researchers have focused their attention on the chemical compounds and biological activity of propolis.

20.
Insects ; 10(6)2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31248110

RESUMO

Entomopathogenic fungi are commonly applied as inundative sprays to protect plants against insect pests. Their artificial establishment as fungal endophytes to provide other benefits to the host plants aside mere protection against the primary pests has also been widely demonstrated. In the present study, two fungal strains of Beauveria bassiana and one strain of Isaria fumosorosea were assessed in a pathogenicity test against adults of Asian citrus psyllid (Diaphorina citri) and found to induce 50% reduction in the survival rate of D. citri adults within 5 days of exposure. The ability of the three fungal strains to endophytically colonize Citrus limon, the impact on plant growth and the effects of systemic colonization on 3 successive generations of D. citri feeding on colonized plants was evaluated. Citrus seedlings at 4 months post-planting were inoculated with each of the fungal strains via foliar spraying. Both strains of B. bassiana successfully colonized the seedlings. One of the B. bassiana strains (BB Fafu-13) was sustained up to 12 weeks in the colonized seedlings, whereas the other B. bassiana strain (BB Fafu-16) was only recovered up to 8 weeks post-inoculation. Isaria fumosorosea (IF Fafu-1) failed to colonize the plant. Both strains of B. bassiana induced significant improvement in plant height and flush production in endophytically colonized seedlings. In addition, endophytic B. bassiana caused 10-15% D. citri adult mortality within 7 days of exposure. Female D. citri feeding on B. bassiana challenged plants laid fewer eggs as compared to those feeding on endophyte-free seedlings, while reduction in adult emergence was recorded on B. bassiana treated plants. With this study, we present the first evidence of B. bassiana artificial establishment as fungal endophyte in citrus plants and its negative effects on D. citri.

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