Evaluation of Forced Expiratory Volume in One Second and Forced Vital Capacity from Age and Height for Pulmonary Function Test

BACKGROUND

Lung function tests (LFTs) are a collection of clinical examinations used to assess lung function and monitor potential declines in the lungs, respiratory muscles, and chest wall's mechanical performance. This cross-sectional study aimed to identify the relation of age and height to lung function.

MATERIAL AND METHODS

The study was conducted at AlHussein Medical City, 70 adult male subjects were enrolled in the study. All subjects were screened physically to ensure that they were normal and there were no respiratory disorders that could affect the lung function. Age and height were taken for these subjects, forced vital capacity (FVC), FEV1 (Forced expiratory volume in first second) as well as FEV1 /FVC ratio were measured.

RESULTS

The results of the study showed that the average values of FVC and FEV1 were 4.75 and 3.88 respectively. There was a significant negative correlation observed between age and FVC (r=0.48), FEV1 (r= 0.6). Also there was a significant positive correlation noticed between Height and FVC (r = 0.62), FEV1 (r =0.69). There was a very high correlation evidenced between FEV1 and FVC, the relation between FEV1 and FVC is practically height and age-independent.

CONCLUSION

Our study highlights a great interest in the study of the relation between age, height, and lung function. The study also creates simple and convenience equations that can be used for reference standards in clinical practice to give reasonable theoretical values for a large sector of the population.

Synthesis, characterization, anti-mycobacterial activity and in silico study of new 2,5-disubstituted-1,3,4-oxadiazole derivatives

A series of new 2,5-disubstituted-1,3,4-oxadiazole derivatives (5a-j and 6a-j) have been designed and synthesized in four-steps. Sixteen compounds among the twenty compounds are reported for the first time. The compounds were characterized and confirmed by the FTIR, 1D- and 2D-NMR and HRMS analyses, and were tested against Mycobacterium smegmatis and Mycobacterium tuberculosis H37Ra. Compound 5d was the most active against M. smegmatis with MIC value of 25 µM, and exhibited cidal activity with MBC of 68 µM, respectively. The time-kill assay showed the good killing rate at 77% with the combination of isoniazid (INH). In addition, checkboard assay confirmed the interaction of compound 5d was categorised as additive. Docking simulation has been performed to position 5d into the pantothenate synthetase active site with binding free energy value -8.6 kcal mol-1. It also occupied the same active site as that of standard native ligand with similar interactions, which clearly indicate their potential as pantothenate synthetase inhibitor.

Synthesis, Characterization, Anti-Mycobacterial Activity and In Silico Study of New 2,5-disubstituted-1,3,4-oxadiazole derivatives.. [DOI: 10.21203/rs.3.rs-1651702/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

A series of new 2,5-disubstituted-1,3,4-oxadiazole derivatives (5a-j and 6a-j) have been designed and synthesized in four-steps. sixteen compounds among the twenty compounds are reported for the first time. The compounds were characterized and confirmed by the FTIR, 1D- and 2D-NMR and HRMS analyses, and were tested against Mycobacterium smegmatis and Mycobacterium tuberculosis H37Ra. Compound 5d was the most active against M. Smegmatis with MIC value of 25 µM, and exhibited cidal activity with MBC of 68 µM, respectively. The time-kill assay showed the good killing rate at 77% with the combination of isoniazid (INH). In addition, checkboard assay confirmed the interaction of compound 5d was categorised as additive. Docking simulation has been performed to position 5d into the pantothenate synthetase active site with binding free energy value –8.6 kcal mol-1. It also occupied the same active site as that of standard native ligand with similar interactions, which clearly indicate their potential as pantothenate synthetase inhibitor.

Design, Synthesis, and Anti-mycobacterial Evaluation of New 3,5-Disubstituted-pyrazole-1-carbothioamides

Two series of new 3,5-disubstituted-pyrazole-1-carbothioamides (4a-f and 5a-e) were designed and synthesized through condensation reaction between chalcones and thiosemicarbazides under alkaline condition via cyclocondensation reaction. The structures have been elucidated by Fourier-transform infrared (FTIR), High-resolution mass spectrometry (HRMS), one- and two-dimensional nuclear magnetic resonance (NMR) analyses. These compounds were assayed for in vitro anti-tuberculosis activity against Mycobacterium tuberculosis H37Ra using the Tetrazolium microplate assay (TEMA) method. As a result, six compounds (i.e., 4a, 4d, 4f, 5a, 5c, and 5d) showed a weak activity with minimum inhibition concentration (MIC) between 650–530 μM, and other compounds showed no inhibition against MTB. In addition, all tested compounds also did not show any cidal effects for minimum bactericidal concentration (MBC), even at the highest test concentration.

Fabaceae: a significant flavonoid source for plant and human health

The Fabaceae is recognized as the third largest and one of the most influential families among the flowering plants. Furthermore, its name is linked to “Legumes”, which represent a vast group of angiosperms in the continents utilized as crops, forages, and green manures. It is recognized for diverse constituents, covering both primary metabolites include lectins, chitinases, various proteases, and α-amylase inhibitors, as well as secondary metabolites include flavonoids, alkaloids, terpenoids, tannins, and phenolics. Fabaceae flavonoid plays an important role in the legumes’ adaptability to biological surroundings as defensive agents (phytoalexins) and as chemical signals in a symbiotic relationship with a bacterial species known as rhizobia. Considering their important role in plant defense and benefits to human healthiness, a number of studies on the Fabaceae plant have been performed, namely isolation and screening of the purified compounds and their biological activity. This study outlines specified issues on the chemical structure, biosynthesis, biological activities, and medicinal uses of Fabaceae compounds.

Bioactivities and Mode of Actions of Dibutyl Phthalates and Nocardamine from Streptomyces sp. H11809

Dibutyl phthalate (DBP) produced by Streptomyces sp. H11809 exerted inhibitory activity against human GSK-3β (Hs GSK-3β) and Plasmodiumfalciparum 3D7 (Pf 3D7) malaria parasites. The current study aimed to determine DBP’s plausible mode of action against Hs GSK-3β and Pf 3D7. Molecular docking analysis indicated that DBP has a higher binding affinity to the substrate-binding site (pocket 2; −6.9 kcal/mol) than the ATP-binding site (pocket 1; −6.1 kcal/mol) of Hs GSK-3β. It was suggested that the esters of DBP play a pivotal role in the inhibition of Hs GSK-3β through the formation of hydrogen bonds with Arg96/Glu97 amino acid residues in pocket 2. Subsequently, an in vitro Hs GSK-3β enzymatic assay revealed that DBP inhibits the activity of Hs GSK-3β via mixed inhibition inhibitory mechanisms, with a moderate IC₅₀ of 2.0 µM. Furthermore, the decrease in K_m value with an increasing DBP concentration suggested that DBP favors binding on free Hs GSK-3β over its substrate-bound state. However, the antimalarial mode of action of DBP remains unknown since the generation of a Pf 3D7 DBP-resistant clone was not successful. Thus, the molecular target of DBP might be indispensable for Pf survival. We also identified nocardamine as another active compound from Streptomyces sp. H11809 chloroform extract. It showed potent antimalarial activity with an IC₅₀ of 1.5 μM, which is ~10-fold more potent than DBP, but with no effect on Hs GSK-3β. The addition of ≥12.5 µM ferric ions into the Pf culture reduced nocardamine antimalarial activity by 90% under in vitro settings. Hence, the iron-chelating ability of nocardamine was shown to starve the parasites from their iron source, eventually inhibiting their growth.

In Vitro Interactions of Costus speciosus (J. Koenig) Sm., Cymbopogon citratus (Dc. Ex Nees) Stapf. and Tabernaemontana coronaria (L.) Willd. with First-Line Anti-Tuberculosis Drugs Against Mycobacterium tuberculosis H37rv

Global tuberculosis (TB) burden underscores the importance of developing new effective anti-TB drugs. This study was concerned with prospecting for potential anti-TB agents from Malaysian medicinal plants. In our previous study, we have reported that n-hexane fractions of Costus speciosus (C. speciosus) (J. Koening) Sm., Cymbopogon citratus (C. citratus ) (DC.) Stapf. and Tabernaemontana coronaria (T. coronaria) (Jacq.) posses promising anti-TB activity against Mycobacterium tuberculosis (M. tuberculosis) H37Rv with minimum inhibitory concentrations (MICs) of 200–100 µg/mL. This study aimed to investigate the interactions of these active fractions with first-line anti-TB drugs (isoniazid, rifampicin, ethambutol and streptomycin) against M. tuberculosis H37Rv using the microdilution checkerboard method. C. citratus (stem-rhizome) n-hexane fraction exhibited synergism with all drugs except ethambutol which showed additive interaction. Synergistic was also observed when C. speciosus (stem-flower) n-hexane and T. coronaria (leaf) n-hexane fractions in combination with rifampicin. C. speciosus (stem-flower) n-hexane and T. coronaria (leaf) n-hexane exhibited additive interaction with isoniazid, ethambutol and streptomycin. Hence, these active plants are worthy of further investigations for the discovery of anti-TB drug leads.

Sampling and Sample Preparation Techniques for the Analysis of Organophosphorus Pesticides in Soil Matrices

Despite organophosphorus pesticides (OPPs) benefits in controlling vector-borne diseases and noxious insects, the bioaccumulation and persistence in the soil system may metamorphose into new substances which could pose a serious threat to the ecosystems and human health. The generally low levels of OPPs residues and often the complexity of the soil matrix are the issues that researcher must deal with. Thus, it is essential to isolate and preconcentrate the OPPs from the matrix to reduce interference effects to obtain a reliable detection. Researchers have reported sample preparation techniques as a promising approach to improve analytical measurement of merits including recovery, precision, linearity, limit of detection, and limit of quantification. Under the selected conditions, limits of detection range between 0.001 and 143 ng/mL, and extraction recovery range between 5 and 154% were obtained. This review evaluates the challenges and opportunities, emphasizes the prospects of sampling techniques and various (micro)extraction coupled with chromatographic methods in different soil samples. Based on the finding, the extraction efficiency depended largely on the interaction between OPPs and extraction media. The fate, migration, toxicity impact, sampling procedure, and storage which influenced the sample preparation were comprehensively discussed.

United Arab Emirates National Newborn Screening Programme:an evaluation 1998-2000

To evaluate the United Arab Emirate National Newborn Screening Programme we compared coverage, timeliness of programme indicators [age at sampling, recall and treatment initiation, timing of specimen delivery and laboratory results] and specimen quality with international st and ards. Recall rate, sensitivity, specificity, positive predictive values and relative incidence rates for phenylketonuria [PKU] and congenital hypothyroidism [CH] were calculated. Investigations for hypothyroidism included thyroid function studies [T3, T4, fT4 and TSH], technetium-99m thyroid scan when possible and thyroglobulin and thyroid antibodies when indicated. PKU investigations included plasma amino acids and measurement of biopterin defects. In the 6 years before December 2000, 138, 718 neonates were screened. Relative incidences for CH and for classic PKU were 1: 1570 and 1: 20, 050 respectively

Physical Properties of Newly Developed Resin Modified Glass Ionomer Cement with Synthesised Coumarin Derivatives

The aim of this study was to determine the effects of two types of coumarin derivatives, namely, 3-acetylcoumarin (AC) and coumarin thiosemicarbazone (CT) on surface characteristics such as the roughness, hardness, and morphology of resin-modified glass-ionomer cement (RMGIC). The release of coumarin from the fabricated RMGIC was also investigated. AC and CT at 1.0% (w/w) concentration were added into 0.3 g of RMGIC powder and mixed with 0.1 g of polyacrylic acid. The fabricated RMGIC-AC and RMGIC-CT were evaluated for surface characteristics such as roughness, hardness and topography. The coumarin release of AC and CT from RMGIC was also determined. The RMGIC-CT demonstrated a decreased roughness value among the materials. The surface roughness exhibited by the RMGIC was statistically higher (p < 0.05) than that of fabricated materials. The RMGIC-AC was observed to have the highest hardness value compared to the RMGIC-CT and RMGIC, and this value was significantly higher (p < 0.05). The surface morphologies of the RMGIC-AC and RMGIC-CT showed a number of pores and irregular surfaces. Meanwhile, the surface roughness value of the RMGIC was statistically higher (p < 0.05) than both RMGIC-AC and RMGIC-CT. In conclusion, the large-sized AC particles significantly increased the surface hardness of the fabricated RMGIC. Conversely, the particle size of both coumarins were not influenced the surface roughness value and the coumarin release profile of fabricated RMGICs.

Cholinesterase Inhibition Activity and Molecular Docking Study of Eugenol Derivatives

The study was conducted to explore the anticholinesterase inhibition property of eugenol derived molecules. Ten eugenol derivatives were synthesized and evaluated for the inhibitory activities against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) by Ellman’s method. Most of the tested derivatives showed higher inhibition on BChE than AChE, however, their overall inhibitory activity was weak. In contrast, three derivatives (compounds 3,6,9) showed higher and good AChE inhibitory activity of more than 50% inhibition at 10 μg/mL. Among them, compound 9bearing a ethyl substituent at para position of the benzoyl ring showed the most potent AChE inhibition, with IC50 of 5.64 μg/mL. Ligand-protein docking simulation was also performed for the most active derived molecules (compounds 3,6,9).

Six-year experience of detection and investigation of possible Middle East Respiratory Syndrome coronavirus cases, England, 2012-2018

OBJECTIVES

Surveillance for Middle East Respiratory Syndrome (MERS) has been undertaken in the UK since September 2012. This study describes the surveillance outcomes in England from 2012 to 2018.

STUDY DESIGN

This was a descriptive study using surveillance data.

METHODS

Local health protection teams in England report possible MERS cases to the National Infection Service with clinical and laboratory data.

RESULTS

A total of 1301 possible MERS cases were identified in the study period. Five cases were laboratory-confirmed MERS. The majority of cases had travelled to Saudi Arabia (56.7%) and United Arab Emirates (25.9%). Fifty-four percent of cases were men and 43.7% were women. The majority of cases (65.1%) were aged 45 years or older. The number of tests increased in the period after Hajj each year. Laboratory-confirmed alternative diagnoses were available for 513 (39.4%) cases; influenza was the most common virus detected (n = 255, 52.4%).

CONCLUSIONS

Our study highlights the importance of differential diagnosis of influenza and other respiratory pathogens and early influenza antiviral treatment.

A European multicentre evaluation of detection and typing methods for human enteroviruses and parechoviruses using RNA transcripts

Polymerase chain reaction (PCR) detection has become the gold standard for diagnosis and typing of enterovirus (EV) and human parechovirus (HPeV) infections. Its effectiveness depends critically on using the appropriate sample types and high assay sensitivity as viral loads in cerebrospinal fluid samples from meningitis and sepsis clinical presentation can be extremely low. This study evaluated the sensitivity and specificity of currently used commercial and in-house diagnostic and typing assays. Accurately quantified RNA transcript controls were distributed to 27 diagnostic and 12 reference laboratories in 17 European countries for blinded testing. Transcripts represented the four human EV species (EV-A71, echovirus 30, coxsackie A virus 21, and EV-D68), HPeV3, and specificity controls. Reported results from 48 in-house and 15 commercial assays showed 98% detection frequencies of high copy (1000 RNA copies/5 µL) transcripts. In-house assays showed significantly greater detection frequencies of the low copy (10 copies/5 µL) EV and HPeV transcripts (81% and 86%, respectively) compared with commercial assays (56%, 50%; P = 7 × 10-5 ). EV-specific PCRs showed low cross-reactivity with human rhinovirus C (3 of 42 tests) and infrequent positivity in the negative control (2 of 63 tests). Most or all high copy EV and HPeV controls were successfully typed (88%, 100%) by reference laboratories, but showed reduced effectiveness for low copy controls (41%, 67%). Stabilized RNA transcripts provide an effective, logistically simple and inexpensive reagent for evaluation of diagnostic assay performance. The study provides reassurance of the performance of the many in-house assay formats used across Europe. However, it identified often substantially reduced sensitivities of commercial assays often used as point-of-care tests.

Numerical and experimental studies of water disinfection in UV reactors

Performance of UV reactors for water disinfection is investigated in this paper. Both experimental and numerical studies are performed on base reactor LP24. Enterobacteria phage MS2 is chosen as the challenge microorganism in the experiments. Experiments are conducted to evaluate the effect of different parameters, i.e. flow rate and UV transmission, on the reactor performance. Simulation is carried out based on the commercial software ANSYS FLUENT with user defined functions (UDFs) implemented. The UDF is programmed to calculate UV dose absorbed by different microorganisms along their flow trajectories. The effect with boundary layer mesh and without boundary layer mesh for LP24 is studied. The results show that the inclusion of boundary layer mesh does not have much effect on the reactor performance in terms of reduction equivalent dose (RED). The numerical results agree well with the experimental measurements, hence validating the numerical model. With this achieved, the numerical model is applied to study other scaled reactors: LP12, LP40, LP60 and LP80. Comparisons show that LP40 has the highest RED and log inactivation among all the reactors while LP80 has the lowest RED and log inactivation.

Molecular docking studies of coumarin hybrids as potential acetylcholinesterase, butyrylcholinesterase, monoamine oxidase A/B and β-amyloid inhibitors for Alzheimer's disease

Coumarins are the phytochemicals, which belong to the family of benzopyrone, that display interesting pharmacological properties. Several natural, synthetic and semisynthetic coumarin derivatives have been discovered in decades for their applicability as lead structures as drugs. Coumarin based conjugates have been described as potential AChE, BuChE, MAO and β-amyloid inhibitors. Therefore, the objective of this review is to focus on the construction of these pharmacologically important coumarin analogues with anti-Alzheimer’s activities, highlight their docking studies and structure–activity relationships based on their substitution pattern with respect to the selected positions on the chromen ring by emphasising on the research reports conducted in between year 1968 to 2017.

4-Thiazolidinone coumarin derivatives as two-component NS2B/NS3 DENV flavivirus serine protease inhibitors: synthesis, molecular docking, biological evaluation and structure-activity relationship studies

A series of novel 4-thiazolidinone inhibitors SKYa-SKYg, containing coumarin as a core structure were synthesized via facile and efficient method. The structures of the synthesized compounds were established by extensive spectroscopic studies (FT IR, 1D NMR, 2D NMR, LC-MS) and elemental analysis. All the synthesized hybrids were further evaluated for their potential as anti-tubercular agents against Mycobacterium tuberculosis H37Rv ATCC 25618, and anti-bacterial agents against Escherichia coli, Enterobacter aerogenes, Salmonella typhi, Streptococcus pneumoniae and Staphylococcus aureus. Interestingly, the hybrids displayed potent bioactivity. However, compounds SKYc, SKYd, and SKYe appeared to be more effective against the tested bacterial strains, among which compound SKYb showed the highest inhibition against all the bacterial strains ranging from 41 to 165 μg/mL, as compared to the standards, streptomycin, kanamycin and vancomycin. Moreover, derivative SKYa was found to be the strongest against M. tuberculosis (83 μg/mL). Additionally, the anti-dengue potential of the coumarin hybrids as two-component NS2B/NS3 DENV flavivirus serine protease inhibitors was calculated using computational molecular docking approach, with reference to the standards 4-hydroxypanduratin, panduratin and ethyl 3-(4-(hydroxymethyl)-2-methoxy-5-nitrophenoxy)propanoate with DS of - 3.379, - 3.189 and - 3.381, respectively. The docking results revealed that the synthesized hybrids exhibited potent anti-dengue activity among which compounds SKYf, SKYd, SKYc and SKYe were found to be the best ones with docking scores of - 4.014, - 3.964, - 3.905 and - 3.889. In summary, we discovered 4-thiazolidinone coumarin derivatives as a new scaffold that may eventually yield useful compounds in the treatment of bacterial and viral infections.

The Effects of 4-Hydroxybenzoic Acid Identified from Bamboo (Dendrocalamus asper) Shoots on Kv1.4 Channel

Background

Bamboo shoot has been used as a treatment for epilepsy in traditional Chinese medicine for generations to treat neuronal disorders such as convulsive, dizziness and headaches. 4-hydroxybenzoic acid (4-hba) is a non-flavonoid phenol found abundantly in Dendrocalamus asper shoots (bamboo), fruits (strawberries and apples) and flowers. Kv1.4 is a rapidly inactivating Shaker-related member of the voltage-gated potassium channels with two inactivation mechanisms; the fast N-type and slow C-type. It plays vital roles in repolarisation, hyperpolarisation and signaling the restoration of resting membrane potential through the regulation of the movement of K⁺ across the cellular membrane.

Methods

Chemical compounds from Dendrocalamus asper bamboo shoots were purified and identified as major palmitic acids mixed with other minor fatty acids, palmitic acid, 4-hydroxybenzaldehyde, lauric acid, 4-hydroxybenzoic acid and cholest-4-ene-3-one. The response of synthetic 4-hydroxybenzoic acid was tested on Kv1.4 potassium channel which was injected into viable oocytes that was extracted from Xenopus laevis. The current were detected by the two-microelectrode voltage clamp, holding potential starting from -80 mV with 20 mV step-up until +80 mV. Readings of treatments with 0.1% DMSO, 4-hba concentrations and K channel blockers were taken at +60 mV. The ratio of tail/peak amplitude is the index of the activity of the Kv1.4 channels with n ≥ 6 (number of oocytes tested). The decreases of the ratios of five different concentrations (1 μM, 10 μM, 100 μM, 1 mM and 2.5 mM) were compared with 0.1% DMSO as the control.

Results

All concentration showed statistically significant results with P < 0.05 except for 100 μM. The normalised current of the 4-hba concentrations were compared with potassium channel blockers (TEA and 4-AP) and all groups showed statistically significant results. This study also showed that time taken for each concentration to affect Kv1.4 does not play any significant roles.

Conclusion

4-hydroxybenzoic acid was found to be able to enhance the inactivation of Kv1.4 by lowering the membrane potential so that the abnormal neuronal firing can be inhibited. With IC50 slightly higher than 10 μM, increasing concentrations (100 μM, 1 mM and 2.5 mM) had shown to exhibit toxicity effects. The best concentration from this study is 10 μM with Hill slope of 0.1799.

Antituberculosis activity, phytochemical identification of Costus speciosus (J. Koenig) Sm., Cymbopogon citratus (DC. Ex Nees) Stapf., and Tabernaemontana coronaria (L.) Willd. and their effects on the growth kinetics and cellular integrity of Mycobacterium tuberculosis H37Rv

Background

Costus speciosus, Cymbopogon citratus, and Tabernaemontana coronaria are herbal plants traditionally used as remedies for symptoms of tuberculosis (TB) including cough. The aims of the present study were to evaluate the in vitro anti-TB activity of different solvent partitions of these plants, to identify the phytochemical compounds, and to assess the effects of the most active partitions on the growth kinetics and cellular integrity of the tubercle organism.

Methods

The in vitro anti-TB activity of different solvent partitions of the plant materials was determined against M. tuberculosis H37Rv using a tetrazolium colorimetric microdilution assay. The phytochemical compounds in the most active partition of each plant were identified using gas chromatography-mass spectrometry (GC-MS) analysis. The effects of these partitions on the growth kinetics of the mycobacteria were evaluated over 7-day treatment period in a batch culture system. Their effects on the mycobacterial cellular integrity were observed under a scanning electron microscope (SEM).

Results

The respective n-hexane partition of C. speciosus, C. citratus, and T. coronaria exhibited the highest anti-TB activity with minimum inhibitory concentrations (MICs) of 100–200 μg/mL and minimum bactericidal concentration (MBC) of 200 μg/mL. GC-MS phytochemical analysis of these active partitions revealed that majority of the identified compounds belonged to lipophilic fatty acid groups. The active partitions of C. speciosus and T. coronaria exhibited high cidal activity in relation to time, killing more than 99% of the cell population. SEM observations showed that these active plant partitions caused multiple structural changes indicating massive cellular damages.

Conclusions

The n-hexane partition of the plant materials exhibited promising in vitro anti-TB activity against M. tuberculosis H37Rv. Their anti-TB activity was supported by their destructive effects on the integrity of the mycobacterial cellular structure.

The Effect of 4-hydroxybenzaldehyde on the γ-aminobutyric Acid Type A Receptor

The α₁β₂γ₂ subtype of GABA_A receptors is the most commonly found GABA_A receptor subtype in the mammalian cortex and hippocampus. It is expressed heterologously in the Xenopus laevis oocyte as a α₁β₂γ₂S/L subtype for application as an in vitro model for the screening of compounds that modulate receptor activities. In fact, 4-hydroxybenzaldehyde (4-HB) has been identified as one of the major components in Dendrocalamus asper bamboo shoots in our previous study, and the current study showed that at 101.7 μM, 4-HB significantly reduced the GABA-induced chloride current of GABA_A receptors expressed on Xenopus oocytes, indicating a possible GABAergic antagonistic effect at high concentrations.

3,5-Bis(arylidene)-4-piperidones as potential dengue protease inhibitors

Dengue is a severe mosquito-borne viral infection causing half a million deaths annually. Dengue virus NS2B/NS3 protease is a validated target for anti-dengue drug design. A series of hitherto unreported 3,5-bis(arylidene)-4-piperidones analogues 4a-4j were synthesized and screened in silico against DENV2 NS2B/NS3 protease to elucidate their binding mechanism and orientation around the active sites. Results were validated through an in vitro DENV2 NS2B/NS3 protease assay using a fluorogenic Boc-Gly-Arg-Arg-AMC substrate. Nitro derivatives of 3,5-bis(arylidene)-4-piperidones (4e and 4j) emerged as promising lead molecules for novel protease inhibitors with an IC₅₀ of 15.22 and 16.23 µmol/L, respectively, compared to the standard, panduratin A, having IC₅₀ of 57.28 µmol/L.

New Anti-Infective Preparations of Naphthyloxypropargylpiperidine Series

1-alkyl-4-(3-naphthyloxyprop-1-ynyl)piperidine-4-ols have been obtained by the condensation of 1-alkyl-pipieridin-4-ones with 1- and 2-naphthoxypropines by the Favorsky method in absolute diethylether, in the presence of powered technical KОН, under atmospheric pressure. Acylation of tertiary naphthoxypropynyl piperidols by cyclopropanecarbonylchloride has been carried out in order to introduce a cyclopropanecarbonyl fragment into the structures of naphthoxypropargylpiperidines. The obtained esters of cyclopropanecarboxylic acid represent crystalline substances with the definite melting temperature, very soluble in water, ethanol, acetone. The composition and structure of the synthesized compounds have been confirmed by the data of elemental analysis, IR-spectroscopy, NMR-spectroscopy, the identity has been confirmed by thin-layer chromatography. The compounds under the code AIP (anti-infective preparation) have been studied for an antimicrobial activity in relation to museum microbial strains. The effects of these preparations have been assessed in vitro in relation to Bacillus subtilis ATCC 6633, Escherichia coli ATCC 25922, Salmonella enterica ATCC 14028 and Staphylococcus aureus ATCC 6538- P. It has been found that the compounds AIP-30 and AIP-31 possess an antimicrobial activity in relation to all strains of microorganisms, engaged in the experiment. AIP- 30 and AIP-31 have antimicrobial effects to different extents, AIP-30 has displayed the highest activity in relation to the museum strain Bacillus subtilis ATCC 6633 in the concentration of 250 μg/ml. It has been established that AIP-32 displays a selective antimicrobial activity towards one type, and AIP-33 ‒ towards two types of the museum strains, engaged in the experiment.

Metabolomics approach for multibiomarkers determination to investigate dengue virus infection in human patients

BACKGROUND

Dengue is one of the major public health problems in the world, affecting more than fifty million cases in tropical and subtropical region every year. The metabolome, as pathophysiological end-points, provide significant understanding of the mechanism and progression of dengue pathogenesis via changes in the metabolite profile of infected patients. Recent developments in diagnostic technologies provide metabolomics for the early detection of infectious diseases.

METHODS

The mid-stream urine was collected from 96 patients diagnosed with dengue fever at Penang General Hospital (PGH) and 50 healthy volunteers. Urine samples were analyzed with proton nuclear magnetic resonance (¹H NMR) spectroscopy, followed by chemometric multivariate analysis. NMR signals highlighted in the orthogonal partial least square-discriminant analysis (OPLS-DA) S-plots were selected and identified using Human Metabolome Database (HMDB) and Chenomx Profiler. A highly predictive model was constructed from urine profile of dengue infected patients versus healthy individuals with the total R²Y (cum) value 0.935, and the total Q²Y (cum) value 0.832.

RESULTS

Data showed that dengue infection is related to amino acid metabolism, tricarboxylic acid intermediates cycle and β-oxidation of fatty acids. Distinct variations in certain metabolites were recorded in infected patients including amino acids, various organic acids, betaine, valerylglycine, myo-inositol and glycine.

CONCLUSION

Metabolomics approach provides essential insight into host metabolic disturbances following dengue infection.

IN VIVO CARBON TETRACHLORIDE-INDUCED HEPATOPROTECTIVE AND IN VITRO CYTOTOXIC ACTIVITIES OF GARCINIA HOMBRONIANA (SEASHORE MANGOSTEEN)

BACKGROUND

Garcinia hombroniana, known as "manggis hutan" (jungle mangosteen) in Malaysia, is distributed in tropical Asia, Borneo, Thailand, Andaman, Nicobar Islands, Vietnam and India. In Malaysia, its ripened crimson sour fruit rind is used as a seasoning agent in curries and culinary dishes. Its roots and leaves decoction is used against skin infections and after child birth. This study aimed to evaluate in vivo hepatoprotective and in vitro cytotoxic activities of 20% methanolic ethyl acetate (MEA) G. hombroniana bark extract.

MATERIALS AND METHODS

In hepatoprotective activity, liver damage was induced by treating rats with 1.0 mL carbon tetrachloride (CCl4)/kg and MEA extract was administered at a dose of 50, 250 and 500 mg/kg 24 h before intoxication with CCl4. Cytotoxicity study was performed on MCF-7 (human breast cancer), DBTRG (human glioblastoma), PC-3 (human prostate cancer) and U2OS (human osteosarcoma) cell lines. 1H, 13C-NMR (nuclear magnetic resonance), and IR (infrared) spectral analyses were also conducted for MEA extract.

RESULTS

In hepatoprotective activity evaluation, MEA extract at a higher dose level of 500 mg/kg showed significant (p<0.05) potency. In cytotoxicity study, MEA extract was more toxic towards MCF-7 and DBTRG cell lines causing 78.7% and 64.3% cell death, respectively. MEA extract in 1H, 13C-NMR, and IR spectra exhibited bands, signals and J (coupling constant) values representing aromatic/phenolic constituents.

CONCLUSIONS

From the results, it could be concluded that MEA extract has potency to inhibit hepatotoxicity and MCF-7 and DBTRG cancer cell lines which might be due to the phenolic compounds depicted from NMR and IR spectra.