Organophosphorus pesticide exposure from house dust and parent-reported child behavior in Latino children from an orchard community

BACKGROUND

Organophosphorus pesticide (OP) exposure is known to have adverse effects on the nervous system. Children from agricultural communities are at risk of exposure to these chemicals from their indoor environments that can lead to neurological and developmental problems, including changes in behavior.

OBJECTIVE

The aim of this study is to evaluate whether the take-home pathway exposure is associated with behavioral and emotional problems in Latino Orchid Community children.

METHOD

The study was implemented over a period of two years (2008-2010) in an orchard farming community with a total of 324 parents who had children between the ages of 5-12 years old. Mothers of the children were asked to complete the Child Behavior Checklist (CBCL) and dust from their carpets was collected. Emotional and behavioral deficits were assessed based on the CBCL and house dust was assessed for OP concentrations. In this study, correlations between OPs in house dust and CBCL subscales were estimated using linear regression models with total OP concentrations classified by tertiles. This study also facilitated the comparison between the agricultural and non-agricultural families in terms of behavioral deficits and house dust concentrations of pesticides.

RESULTS

The data from the study shows that there was a positive association between the concentration of OP residues in house dust and internalizing behavior (β=2.06, p=0.05) whereas the association with externalizing behavior was not significant after accounting for sociocultural covariates. Significant positive associations of OP residues with somatic problems (p=0.02) and thought problems (p=0.05) were also found.

CONCLUSION

The data support a potential role of OP exposure in childhood development, with a specific focus on internalizing behavior. Future work focused on longitudinal studies may uncover the long-term consequences of OP exposure and behavior.

Biochemical and In Silico Studies on Triazole Derivatives as Tyrosinase Inhibitors: Potential Treatment of Hyperpigmentation Related Skin Disorders

INTRODUCTION

Tyrosinase is a versatile, glycosylated copper-containing oxidase enzyme that mainly catalyzes the biosynthesis of melanin in mammals. Its overexpression leads to the formation of excess melanin, resulting in hyperpigmentary skin disorders, such as dark spots, melasma, freckles, etc. Therefore, inhibition of tyrosinase is a therapeutic approach for the treatment of hyperpigmentation.

METHOD

The current study focused on evaluating tyrosinase inhibitory activities of triazole derivatives 1-20, bearing different substituents on the phenyl ring. 17 derivatives have shown a potent tyrosinase inhibition with IC50 values between 1.6 to 13 μM, as compared to the standard drug, i.e., kojic acid (IC50 = 24.1 ± 0.5 μM). Particularly, compounds 11 and 15 displayed 12 times more potent inhibitory effects than the kojic acid.

RESULT

The structure-activity relationship revealed that substituting halogens at the C-4 position of the benzene ring renders remarkable anti-tyrosinase activities. Compounds 1-3 and 8 showed a competitive type of inhibition, while compounds 5, 11, and 15 showed a non-competitive mode of inhibition. Next, we performed molecular docking analyses to study the binding modes and interactions between the ligands (inhibitors) and the active site of the tyrosinase enzyme (receptor). Besides this, we have assessed the toxicity profile of inhibitors on the BJ human fibroblast cell line.

CONCLUSION

The majority of the newly identified tyrosinase inhibitors were found to be noncytotoxic. The results presented herein form the basis of further studies on triazole derivatives as potential drug leads against tyrosinase-related diseases.

Outcomes of Portosystemic Shunts in Children with and without Liver Transplantation

Purpose

Limited data exist regarding outcome and morbidity associated with portosystemic shunts in the pediatric transplant population. Our study assesses the outcomes of pediatric patients who underwent a portosystemic shunt procedure, both with and without liver transplantation (LT).

Methods

This study retrospectively reviewed the medical records of pediatric patients aged 0-19 years who underwent shunt placement between 2003 and 2017 at a tertiary care center. The analysis included cases of shunt placement with or without LT.

Results

A total of 13 pediatric patients were included in the study with median age of 8.8 years. Among the cases, 11 out of 13 (84.6%) underwent splenorenal shunt, 1 (7.7%) underwent a mesocaval shunt, and another 1 (7.7%) underwent a Modified Rex (mesoportal) shunt. Additionally, 5 out of 13 (38.5%) patients had LT, with 4 out of 5 (80.0%) receiving the transplant before shunt placement, and 1 out of 5 (20.0%) receiving it after shunt placement. Gastrointestinal bleeding resulting from portal hypertension was the indication in all cases. A total of 10 complications were reported in 5 patients; the most common complication was anemia in 3 (23.1%) patients. At the most recent follow-up visit, the shunts were functional without encephalopathy, and no deaths were reported.

Conclusion

Shunt placement plays a crucial role in the management of patients with portal hypertension. Our study demonstrates favorable long-term outcomes in pediatric patients who underwent shunt placement. Long term shunt outcomes were similar and unremarkable in patients with LT and without LT.

Role of Metals on SARS-CoV-2 Infection: a Review of Recent Epidemiological Studies

PURPOSE OF REVIEW

Metals and metalloids are known for their nutritional as well as toxic effects in humans. In the context of the SARS-CoV-2 pandemic, understanding the role of metals on COVID-19 infection is becoming important due to their role in infectious diseases. During the past 2 years, a significant number of studies have examined the impact of metals and metalloids on COVID-19 morbidity and mortality. We conducted a systematic review of peer-reviewed manuscripts on the association of metals and metalloids with SARS-CoV-2 infection and COVID-19 severity published since the onset of the pandemic.

RECENT FINDINGS

We searched for epidemiological studies available through the PubMed database published from January 2020 to December 2022. Of 92 studies identified, 20 met our inclusion criteria. These articles investigated the association of zinc (Zn), iron (Fe), selenium (Se), manganese (Mn), cadmium (Cd), arsenic (As), copper (Cu), magnesium (Mg), chromium (Cr), and/or lead (Pb) levels on SARS-CoV-2 infection and/or COVID-19 severity. Of the ten metals and metalloids of interest that reported either positive, negative, or no associations, Zn yielded the highest number of articles (n = 13), followed by epidemiological studies on Se (n = 7) and Fe (n = 5). Elevated serum Zn and Se were associated with reduced COVID-19 severity and mortality. Similarly, higher levels of serum Fe were associated with lower levels of cellular damage and symptoms of SARS-CoV-2 infection and with faster recovery from COVID-19. On the other hand, higher serum and urinary Cu and serum Mg levels were associated with higher COVID-19 severity and mortality. Along with the positive or negative effects, some studies reported no impact of metals on SARS-CoV-2 infection. This systematic review suggests that metals, particularly Zn, Fe, and Se, may help reduce the severity of COVID-19, while Cu and Mg may aggravate it. Our review suggests that future pandemic mitigation strategies may evaluate the role of Zn, Se, and Fe as potential therapeutic interventions.

Multitargeted inhibition of key enzymes associated with diabetes and Alzheimer's disease by 1,3,4-oxadiazole derivatives: Synthesis, in vitro screening, and computational studies

A library of 22 derivatives of 1,3,4-oxadiazole-2-thiol was synthesized, structurally characterized, and assessed for its potential to inhibit α-amylase, α-glucosidase, acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and antioxidant activities. Most of the tested compounds demonstrated good to moderate inhibition potential; however, their activity was lower than that of the standard acarbose. Significantly, compound 3f exhibited the highest inhibition potential against α-glucosidase and α-amylase enzymes, with IC50 values of 18.52 ± 0.09 and 20.25 ± 1.05 µM, respectively, in comparison to the standard acarbose (12.29 ± 0.26; 15.98 ± 0.14 µM). Compounds also demonstrated varying degrees of inhibitory potential against AChE (IC50  = 9.25 ± 0.19 to 36.15 ± 0.12 µM) and BChE (IC50  = 10.06 ± 0.43 to 35.13 ± 0.12 µM) enzymes compared to the standard donepezil (IC50  = 2.01 ± 0.12; 3.12 ± 0.06 µM), as well as DPPH (IC50  = 20.98 ± 0.06 to 52.83 ± 0.12 µM) and ABTS radical scavenging activities (IC50  = 22.29 ± 0.18 to 47.98 ± 0.03 µM) in comparison to the standard ascorbic acid (IC50  = 18.12 ± 0.15; 19.19 ± 0.72). The kinetic investigations have demonstrated that the compounds exhibit competitive-type inhibition for α-amylase, noncompetitive-type inhibition for α-glucosidase and AChE, and mixed-type inhibition for BChE. Additionally, a molecular docking study was performed on all synthetic oxadiazoles to explore the interaction details of these compounds with the active sites of the enzymes.

Idiopathic Ileal Ulceration After Intestinal Transplantation

Background

Idiopathic ileal ulceration after intestinal transplantation (ITx) has been discussed infrequently and has an uncertain natural history and relation to graft rejection. Herein, we review our experience with this pathology.

Methods

We retrospectively reviewed 225 ITx in 217 patients with minimum 1 y graft survival. Routine graft endoscopy was conducted up to twice weekly within the first 90 d after ITx, gradually decreasing to once yearly. Risks for ulceration over time were evaluated using Cox regression.

Results

Of 93 (41%) patients with ulcers, 50 were found within 90 d after ITx mostly via ileoscopy; delayed healing after biopsy appeared causal in the majority. Of the remaining 43 patients with ulcers found >90 d after ITx, 36 were after ileostomy closure. Multivariable modeling demonstrated within 90-d ulcer associations with increasing patient age (hazard ratio [HR], 1.027; P < 0.001) and loop ileostomy (versus Santulli ileostomy; HR, 0.271; P < 0.001). For ulcers appearing after ileostomy closure, their sole association was with absence of graft colon (HR, 7.232; P < 0.001). For ulcers requiring extended anti-microbial and anti-inflammatory therapy, associations included de novo donor-specific antibodies (HR, 3.222; P < 0.007) and nucleotide oligomerization domain mutations (HR, 2.772; P < 0.016). Whole-cohort post-ITx ulceration was not associated with either graft rejection (P = 0.161) or graft failure (P = 0.410).

Conclusions

Idiopathic ulceration after ITx is relatively common but has little independent influence on outcome; risks include ileostomy construction, colon-free ITx, immunologic mutation, and donor sensitization.

Determining the 3-substituted Coumarins inhibitory potential against the HslV protease of E. coli

OBJECTIVE

The growing bacterial resistance towards classical antibiotics demands the development of novel approaches for the effective treatment of potentially fatal bacterial infections in humans. Proteostasis is crucial for the survival of every living cell, as several important physiological functions depend on well-regulated proteostasis. Within bacteria, the regulation of proteostasis relies on AAA+ (Adenosine 5'-triphosphatases associated with diverse cellular activities), ATPases, such as the HslVU complex (heat shock locus gene products U and V), along with other proteases. The HslVU protease/chaperon complex is thought to be the progenitor of the eukaryotic proteasome that regulates proteostasis mostly in prokaryotes. This study aimed to determine the inhibitory potential of 3-substituted coumarin derivatives against Escherichia coli heat shock locus V (HslV) protease.

MATERIALS AND METHODS

In this study, twenty-three derivatives of 3-substituted coumarin were assessed for their inhibitory potential against E. coli HslV protease using both in-vitro and in-silico techniques.

RESULTS

Among all the tested compounds, US-I-64, US-I-66, US-I-67, and US-I-68 displayed notable inhibitory potential against the HslV protease, showing IC50 (half maximal inhibitory concentration) values ranging from 0.2 to 0.73 μM. Additionally, the inhibitory potential of these compounds against the eukaryotic proteasome was also evaluated using a separate in-silico study. It was found that these compounds did not bind with the proteasomal active site, suggesting no apparent side effects of these lead molecules.

CONCLUSIONS

These identified HslV protease inhibitors can be used for the development of novel and safer anti-bacterial drugs.

Synthetic piperidine-substituted chalcones as potential hits for α-amylase inhibitory and antioxidant activities

Background: In medicinal chemistry, searching for new therapeutic entities to treat diabetes mellitus is of great concern. The piperidinyl-substituted chalcone scaffold has piqued our interest as a potential antidiabetic agent. Methods: A variety of piperidinyl-substituted chalcones 2-28 were synthesized and tested for α-amylase inhibitory and 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical-scavenging activities. Results: Compared with the standard acarbose, all compounds inhibited α-amylase, with IC₅₀ values of 9.86-35.98 μM. Docking studies revealed an important binding interaction with the enzyme's catalytic site. The compounds also demonstrated promising radical-scavenging potential against DPPH and ABTS radicals. Conclusion: This study has identified potential lead candidates for further advanced research searching for antidiabetic agents.

Thiourea derivatives inhibit key diabetes-associated enzymes and advanced glycation end-product formation as a treatment for diabetes mellitus

This study was designed to screen novel thiourea derivatives against different enzymes, such as α-amylase, α-glucosidase, protein tyrosine phosphatase 1 B, and advanced glycated end product (AGEs). A cytotoxicity analysis was performed using rat L6 myotubes and molecular docking analysis was performed to map the binding interactions between the active compounds and α-amylase and α-glucosidase. The data revealed the potency of five compounds, including E (1-(2,4-difluorophenyl)-3-(3,4-dimethyl phenyl) thiourea), AG (1-(2-methoxy-5-(trifluoromethyl) phenyl)-3-(3-methoxy phenyl) thiourea), AF (1-(2,4-dichlorophenyl)-3-(4-ethylphenyl) thiourea), AD (1-(2,4-dichlorophenyl)-3-(4-ethylphenyl) thiourea), and AH (1-(2,4-difluorophenyl)-3-(2-iodophenyl) thiourea), showed activity against α-amylase. The corresponding percentage inhibitions were found to be 85 ± 1.9, 82 ± 0.7, 75 ± 1.2, 72 ± 0.4, and 65 ± 1.1%, respectively. These compounds were then screened using in vitro assays. Among them, AH showed the highest activity against α-glucosidase, AGEs, and PTP1B, with percentage inhibitions of 86 ± 0.4% (IC₅₀  = 47.9 μM), 85 ± 0.7% (IC₅₀  = 49.51 μM), and 85 ± 0.5% (IC₅₀  = 79.74 μM), respectively. Compound AH showed an increased glucose uptake at a concentration of 100 μM. Finally, an in vivo study was conducted using a streptozotocin-induced diabetic mouse model and PTP1B expression was assessed using real-time PCR. Additionally, we examined the hypoglycemic effect of compound AH in diabetic rats compared to the standard drug glibenclamide.

Author Correction: Inhibitory potential of triazines and hydrazinyl thiazole substituted chromones against the HslVU protease/chaperone complex, a novel drug target

Correction to: European Review for Medical and Pharmacological Sciences 2022; 26 (22): 8567-8575. DOI: 10.26355/eurrev_202211_30392-PMID: 36459037-published online on November 30, 2022. After publication, the authors applied some corrections to the text: - Dr. U. Salar's affiliation has been corrected as follows: Dr. Panjwani Center for Molecular Medicine and Drug Research, International Center for Chemical and Biological Sciences, University of Karachi, Karachi, Pakistan. - The values in the row "Binding energy with HsIV (Kcal/mol)" Table I have been corrected as follows: from -8.4 into -9.0; from -8.6 into -9.2; from -8.0 into -8.5 from -8.3 into -8.7. There are amendments to this paper. The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/30392.

Inhibitory potential of triazines and hydrazinyl thiazole substituted chromones against the HslVU protease/chaperone complex, a novel drug target

OBJECTIVE

Proteostasis is an important process occurring in all living cells and is highly indispensable for cell survival. The HslVU protease/chaperone complex's critical role in regulating proteostasis to maintain a healthy cellular proteome and its presence in pathogenic microbes made it an important drug target. This study aimed to identify small molecular inhibitors of the HslV protease.

MATERIALS AND METHODS

Herein, a library of small molecules belonging to the triazine and chromone families has been evaluated for their inhibitory potential against the E. coli HslV protease using both in silico and in vitro techniques.

RESULTS

Four compounds, i.e., SHS-II-123a, SHS-II-147a, US-IV-89, and US-IV-92, were identified as potential inhibitors of the HslV protease having IC50 values in the range of 0.1 to 0.32 µM. Additionally, these compounds' drug-likeness and ADMET profiles indicated their compatibility to be considered safer drug candidates.

CONCLUSIONS

To the best of our knowledge, this is the first report on small molecules having inhibitory effects on the HslVU complex. These identified compounds can be efficiently subjected to further investigations to develop novel and safer antimicrobial agents.

Mismatch epitope load predicts de novo-DSA-free survival in pediatric liver transplantation

BACKGROUND

Our knowledge of de novo anti-HLA donor-specific antibodies (dnDSA) in liver transplantation continues to be defined. We hypothesized that differences of HLA-DR/DQ mismatches can improve precision in alloimmune risk categorization and be applied to tailor immunosuppression.

METHODS

A retrospective chart review of 244 pediatric patients consecutively transplanted at our center between 2003 and 2019 was performed to identify patients tested for dnDSA. Records were queried for: demographics, pre-transplant diagnosis, biopsy-proven T-cell-mediated rejection (TCMR), radiology proven biliary complications, tacrolimus trough levels, dnDSA characteristics, and HLA typing. The eplet mismatch analyses were performed using HLAMatchmaker^™ 3.1. All statistical analyses were conducted using R software version 3.40.

RESULTS

There were 99 dnDSA-negative patients and 73 dnDSA-positive patients (n = 70 against class II and n = 3 against class I and II). ROC analysis identified optimal cutoff of eplet mismatch load for dnDSA and defined risk groups for an alloimmune outcome. Kaplan-Meier curves and log-rank tests showed high eplet mismatch load was associated with shorter dnDSA-free survival (log-rank p = .001). Multivariable Cox regression models showed that tacrolimus coefficient of variation and tacrolimus mean levels were significantly associated with dnDSA-free survival (p < .001 and p = .036). Fisher's exact test showed that dnDSA was associated with an increased likelihood of TCMR (OR 14.94; 95% CI 3.65 - 61.19; p < .001). Patients without TCMR were more likely to have dnDSA to HLA-DQ7 and less likely to have dnDSA to HLA-DQ2 (p = .03, p = .080).

CONCLUSIONS

Mismatched epitope load predicts dnDSA-free survival in pediatric liver transplant, while dnDSA specificity may determine alloimmune outcome.

Isatin thiazoles as antidiabetic: Synthesis, in vitro enzyme inhibitory activities, kinetics, and in silico studies

Diabetes mellitus is one of the most prevalent diseases nowadays. Several marketed drugs are available for the cure and treatment of diabetes, but there is still a dire need of introducing compatible drug molecules with lesser side effects. The current study is based on the synthesis of isatin thiazole derivatives 4-30 via the Hantzsch reaction. The synthetic compounds were characterized using different spectroscopic techniques and evaluated for their α-amylase and α-glucosidase inhibition potential. Of 27 isatin thiazoles, five (4, 5, 10, 12, and 16) displayed good activities against the α-amylase enzyme with IC₅₀ values in the range of 22.22 ± 0.02-27.01 ± 0.06 µM, and for α-glucosidase, the IC₅₀ values of these compounds were in the range of 20.76 ± 0.17-27.76 ± 0.17 µM, respectively. The binding interactions of the active molecules within the active site of enzymes were studied with the help of molecular docking studies. In addition, kinetic studies were carried out to examine the mechanism of action of the synthetic molecules as well. Compounds 3a, 4, 5, 10, 12, and 16 were also examined for their cytotoxic effect and were found to be noncytotoxic. Thus, several molecules were identified as good antihyperglycemic agents, which can be further modified to enhance inhibition ability and to find the lead molecule that can act as a potential antidiabetic agent.

Biology-oriented drug synthesis and evaluation of secnidazole esters as novel enzyme ınhibitors

The identification of novel compounds that can inhibit physiologically and metabolically important drug targets or enzymes has prime importance in medicinal chemistry. With this aim, a range of secnidazole esters 1-30 were synthesized under the heading of biology-oriented drug synthesis by the 1,1'-carbonyldiimidazole-mediated coupling reaction between secnidazole and varyingly benzoic acid derivatives. All compounds were screened for inhibitory activity against human carbonic anhydrase (hCA) I and II, acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and α-glucosidase. The results indicate that all the synthesized compounds showed potent inhibitory activities against all targets, as compared to the standard inhibitors, revealed by IC₅₀ values. K_i values of the secnidazole derivatives 1-30 for hCA I, hCA II, AChE, BChE, and α-glucosidase enzymes were obtained in the ranges of 47.37-190.74, 44.38-198.21, 12.14-68.37, 8.04-61.53, and 7.78-45.91 nM, respectively. To assess the enzyme-ligand interactions, the optimized most active compounds 2, 3, 8, 9, 14, 17, and 23 were subjected to molecular docking studies with modeled AChE, BChE, hCA I, hCA II, and α-glucosidase enzymes, where several important and key interactions were monitored with amino acid residues of each target enzyme.

Novel Tetrazoles against Acanthamoeba castellanii Belonging to the T4 Genotype

BACKGROUND

Acanthamoeba castellanii is a pathogenic free-living amoeba responsible for blinding keratitis and fatal granulomatous amoebic encephalitis. However, treatments are not standardized but can involve the use of amidines, biguanides, and azoles.

OBJECTIVES

The aim of this study was to synthesize a variety of synthetic tetrazole derivatives and test their activities against A. castellanii.

METHODS

A series of novel tetrazole compounds were synthesized by one-pot method and characterized by NMR and mass spectroscopy. These compounds were subjected to amoebicidal, and cytotoxicity assays against A. castellanii belonging to the T4 genotype and human keratinocyte skin cells respectively. Additionally, reactive oxygen species determination and electron microscopy studies were carried out. Furthermore, two of the seven compounds were conjugated with silver nanoparticles to study their antiamoebic potential.

RESULTS

A series of seven tetrazole derivatives were synthesized successfully. The selected tetrazoles showed anti-amoebic activities at 10µM concentration against A. castellanii in vitro. The compounds tested caused increased reactive oxygen species generation in A castellanii, and significant morphological damage to amoebal membranes. Moreover, conjugation of silver nanoparticles enhanced antiamoebic effects of two tetrazoles.

CONCLUSIONS

The results showed that azole compounds hold promise in the development of new formulations of anti-Acanthamoebic agents.

ROS Inhibitory Activity and Cytotoxicity Evaluation of Benzoyl, Acetyl, Alkyl Ester, and Sulfonate Ester Substituted Coumarin Derivatives

BACKGROUND

A number of non-steroidal anti-inflammatory drugs (NSAIDs) including aspirin, indomethacin, ibuprofen, flufenamic acid, and phenylbutazone are being clinically used to treat inflammatory disorders. These NSAIDs are associated with serious side effects such as gastric ulceration, nephrotoxicity, and bleeding. Therefore, the identification of potent and safe therapy for inflammatory disorders is still of great interest to the medicinal chemist.

METHODS

A series of varyingly substituted benzoyl, acetyl, alkyl ester, and sulfonate ester substituted coumarins 1-64 were screened for the inhibition of ROS, generated from zymosan activated whole blood phagocytes, using luminol-enhanced chemiluminescence technique.

RESULTS

Among all tested compounds, 8 (IC₅₀ = 65.0 ± 3.1 μM), 24 (IC₅₀ = 41.8 ± 1.5 μM), 26 (IC₅₀ = 10.6 ± 2.8 μM), 28 (IC₅₀ = 20.9 ± 1.5 μM), and 41 (IC₅₀ = 4.6 ± 0.3 μM) showed good anti- inflammatory potential as compared to standard antiinflammatory drug ibuprofen (IC₅₀ = 54.3 ± 1.9 μM). Specifically, compounds 24, 26, 28, and 41 showed superior activity than standard antiinflammatory drug. Furthermore, compounds 12 (IC₅₀ = 219.0 ± 1.4 μM), 14 (IC₅₀ = 216.5 ± 6.2 μM), 16 (IC50 = 187.4 ± 2.2 μM), and 20 (IC₅₀ = 196.2 ± 2.0 μM) showed moderate ROS inhibitory activity. Limited SAR study revealed that the hydroxy-substituted compound showed better ROS inhibition potential in case of 3-benzoyl and 3-ethylester coumarin derivatives. Whereas, chloro substitution was found to be important in case of 3-acetyl coumarin derivatives. Similarly, in case of sulfonate ester, chloro, and nitro groups especially at positions -4 and -3 of ring "R" played vital role in ROS inhibition. Furthermore, cytotoxicity of all active compounds was also checked on NIH-3T3 cell line. Compounds 12, 14, and 20 were found to be non-cytotoxic. Whereas, 8, 16, 24, 26, 28, and 41 were found to be very weak cytotoxic as compared to standard cycloheximide (IC₅₀ = 0.13 ± 0.02 μM).

CONCLUSION

Identified ROS inhibitors offer the possibility of additional modifications that could give rise to lead structures for further research in order to obtain more potent, and safer antiinflammatory agent.

Synthesis, In vitro α-Glucosidase Inhibitory Potential and Molecular Docking Studies of 2-Amino-1,3,4-Oxadiazole Derivatives

BACKGROUND

In the recent past, we have synthesized and reported different derivatives of oxadiazoles as potential α-glucosidase inhibitors, keeping in mind, the pharmacological aspects of oxadiazole moiety and in continuation of our ongoing research on the chemistry and bioactivity of new heterocyclic compounds.

METHODS

1,3,4-Oxadiazole derivatives (1-14) have been synthesized and characterized by different spectroscopic techniques such as 1H-, 13C-NMR and HREI-MS.

RESULTS

The synthetic derivatives were screened for α-glucosidase inhibitory potential. All compounds exhibited good inhibitory activity with IC50 values ranging between 0.80 ± 0.1 to 45.1 ± 1.7 μM in comparison with the standard acarbose having IC50 value 38.45 ± 0.80 μM.

CONCLUSION

Thirteen compounds 1-6 and 8-14 showed potential inhibitory activity as compared to the standard acarbose having IC50 value 38.45 ± 0.80 μM, however, only one compound 7 (IC50 = 45.1 ± 1.7 μM) was found to be less active. Compound 14 (IC50 = 0.80 ± 0.1 μM) showed promising inhibitory activity among all synthetic derivatives. Molecular docking studies were also conducted for the active compounds to understand the ligand-enzyme binding interactions.

Reliability of a computer-based neurobehavioral assessment test battery for Bangladeshi adolescent children

In developing countries, there is a need for low-cost neurobehavioral (NB) test batteries for vulnerable populations, particularly for children exposed to environmental neurotoxicants. The objective of the current study was to assess the feasibility and test-retest reliability of the Behavioral Assessment and Research System (BARS) in children from a rural community in Bangladesh. Fifty healthy adolescents living in the Health Effects of Arsenic Longitudinal Study (HEALS) area in Araihazar, Bangladesh completed all six tests from the BARS in two test sessions scheduled two weeks apart. The BARS tests evaluated NB functions such as motor coordination, attention, memory, and information processing speed. The reliability assessment, evaluated by test-retest correlations demonstrated moderate to strong correlations (i.e., correlation coefficients ranged from 0.43 to 0.85), which were statistically significant (p < 0.05). Paired t-tests for comparing the test and retest outcomes indicated significant improvement in NB performance, highlighting learning and practice effects. NB performance improved with increasing age in most cases. Adolescent boys performed better than the girls in Finger Tapping, Digit Span, and Simple Reaction Time, whereas the girls performed better in Continuous Performance and Symbol Digit tests. The reliability scores (Pearson's correlations 0.43-0.85) were consistent with other children studies in different cultural settings. The effects of age and sex on NB tests were also consistent with findings reported in other countries. Overall, the findings of the study support the feasibility of using this computer-based test system to assess vulnerability of brain health due to environmental exposures among rural Bangladeshi children.

Early initiation of insulin attenuates histological and functional changes in the liver of streptozotocin-induced diabetic rats using 99mTc-sulfur colloid functional imaging

This study aimed to investigate the effect of insulin on the reticuloendothelial system (RES) in the liver and spleen in diabetic rats. Sprague Dawley rats were divided into control, diabetic rats (DM) and diabetic rats treated with insulin (IDM) for 2 weeks. Rats were imaged with technetium-99m-sulfur colloid (^99mTc-SC) tracer to determine regional distributions of the tracer for all groups by drawing regions of interest and then obtained the ratios as the cumulative counts of heart, liver, and spleen to the whole body (WB). Liver tissue from sacrificed rats from each group was examined by light and electron microscopy. ^99mTc-SC uptake ratios showed a lower liver to WB uptake ratio in the DM rats compared to both controls and IDM rats. Electron microscopy showed severe vacuolization of the hepatocytes of DM rats. The IDM rats show complete resolution of the vacuolization. The early administration of insulin for 2 weeks to diabetic rats could significantly resolve the phagocytic RES function and histological changes in the liver.

Antiglycation Activity of Triazole Schiff's Bases Against Fructosemediated Glycation: In Vitro and In Silico Study

BACKGROUND

Advanced glycation end products (AGEs) are known to be involved in the pathophysiology of diabetic complications, neurodegenerative diseases, and aging. Preventing the formation of AGEs can be helpful in the management of these diseases.

OBJECTIVES

Two classes of previously synthesized traizole Schiff's bases (4H-1,2,4-triazole-4- Schiff's bases 1-14, and 4H-1,2,4-triazole-3-Schiff's bases 15-23) were evaluated for their in vitro antiglycation activity.

METHODS

In vitro fructose-mediated human serum albumin (HSA) glycation assay was employed to assess the antiglycation activity of triazole Schiff's bases. The active compounds were subjected to cytotoxicity analysis by MTT assay on mouse fibroblast (3T3) cell line. Molecular docking and simulation studies were carried out to evaluate the interactions and stability of compounds with HSA. Anti-hyperglycemic and antioxidant activities of selected non-cytotoxic compounds were evaluated by in vitro α-glucosidase inhibition, and DPPH free radical scavenging assays, respectively.

RESULTS

Compound 1 (IC50=47.30±0.38 µM) from 4H-1,2,4-triazole-4-Schiff's bases has exhibited antiglycation activity comparable to standard rutin (IC50=54.5±0.05 µM) along with a stable RMSD profile in MD simulation studies. Compound 1 also exhibited a potent α-glucosidase inhibitory activity, and moderate antioxidant property. Other derivatives showed a weak antiglycation activity with IC50 values between 248.1-637.7 µM. Compounds with potential antiglycation profile were found to be non-cytotoxic in a cellular assay.

CONCLUSION

The study identifies triazole Schiff's bases active against fructose-mediated glycation of HSA, thus indicates their potential against late diabetic complications due to production of advancedend products (AGEs).

Antibiotic Resistance in Microbes from Street Fruit Drinks and Hygiene Behavior of the Vendors in Delhi, India

Microbial contamination of fruit juices has caused major outbreaks, leading to significant morbidity and mortality in developing countries. The inept hygiene and safety practices followed by the juice vendors are the leading risk factors of the microbial contamination of juices. In this pilot study, the five most crowded markets in urban Delhi, including Kamla Nagar, University of Delhi (north campus), Tilak Nagar, Chandni Chowk, and Rohini, were selected for a questionnaire survey on the fruit juice vendors and the sampling of water used for juice preparation as well as sugarcane, orange, and mix fruit juices collected from these markets for the enumeration of total bacterial count (TBC), Escherichia coli, Salmonella, and Vibrio. Antibiotic susceptibility tests were performed using ampicillin, cefotaxime, chloramphenicol, ciprofloxacin, and imipenem. The results indicated that the majority of the vendors were not following hygiene and safety practices when compared with the recommended standard safety practices. The use of municipal water by 95% of vendors with high TBC counts might have been the major source of microbial contamination in all types of fruit juices. E. coli and Salmonella contaminations were high in sugarcane (2 × 10⁵ colony forming units (CFU)/mL) and mix fruit (2.2 × 10⁵ CFU/mL) juice samples, respectively. On the other hand, Vibrio was found to be absent in almost all juice samples except for orange juice. All strains were found to be susceptible to chloramphenicol, but resistant to ampicillin and cefotaxime. Only a few strains were resistant to ciprofloxacin, and only E. coli strains were resistant to imipenem. Taken together, the overall microbiological standards of fruit juices served by street vendors were not within the acceptable limits, perhaps due to the poor quality of water used to prepare juices and poor hygiene and safety practices followed by the vendors. More importantly, the isolated microbes demonstrated resistance to ampicillin and cefotaxime, which may have pressing public health implications. Post hoc power analyses identified the minimum sample size required for 80% power.

Benzophenone Sulfonamide Derivatives as Interacting Partners and Inhibitors of Human P-glycoprotein

BACKGROUND

Human P-glycoprotein (P-gp) is a transmembrane protein that belongs to the ATPBinding Cassette (ABC) transporters family. Physiologically, it exports toxins out of the cell, however, its overexpression leads to the phenomena of Multidrug-Resistance (MDR) by exporting a diverse range of compounds, which are structurally and chemically different from each other, thus creating a hurdle in the treatment of various diseases including cancer. The current study was designed to screen benzophenone sulfonamide derivatives as a class of inhibitors and potential anticancer agents for P-gp.

METHODS

A total number of 15 compounds were evaluated. These compounds were screened in daunorubicin efflux inhibition assays using CCRF-CEM Vcr1000 cell line that overexpressed human P-gp. Cytotoxicity assay was also performed for active compounds 11, 14, and 13. These scaffolds were then docked in the homology model of human P-gp using mouse P-gp as a template (PDB ID: 4MIM) and the recently published Cryo Electron Microscopy (CEM) structure of human mouse chimeric P-gp to find their interactions with specified residues in the binding pocket. Analysis was performed using Labview VI and Graph pad prism version 5.0.

RESULTS

Results revealed the potency of all these compounds in low nanomolar range whereas, compound 14 was found to be most active with IC50 value of 18.35nM±4.90 followed by 11 and 13 having IC50 values of 30.66nM±5.49 and 46.12nM±3.06, respectively. Moreover, IC50 values calculated for 14, 11 and 13 in cytotoxicity assay were found to be 22.97μM±0.026, 583.1μM±0.027 and 117.8μM±0.062, respectively. Docking results showed the interaction of these scaffolds in transmembrane helices (TM) where Tyr307, Tyr310, Tyr953, Met986 and Gln946 were found to be the major interaction partners, thus they might play a significant role in the transport of these scaffolds.

CONCLUSION

Benzophenone sulfonamide derivatives showed IC50 values in low nanomolar range comparable to the standard inhibitor Verapamil, therefore they can be good inhibitors of P-gp and can serve as anticancer agents. Also, they have shown interactions in the transmembrane region sharing the same binding region of verapamil and zosuquidar.

Amlodipine/Valsartan (Avsar®): Efficacy in Hypertensive Patients - A Real World Observational Study (ALERT)

Objectives: Hypertension is a significant public health problem and one of the major noncommunicable diseases at the endemic level in Pakistan. This study was done to determine the efficacy of amlodipine/valsartan (Aml/Val) once-daily dose in reducing blood pressure (BP) after eight weeks of therapy.

Methods: This study is an open-labeled observational study carried out for a period of 12 months. Some 769 participants of either gender between the ages of 18 and 70 years selected after taking written informed consent had a BP of >139/89 mmHg (not controlled) on monotherapy with a minimum 30 days of treatment. Therapy to control their high BP was initiated with Aml/Val (Avsar^®, PharmEvo Pvt Ltd, Karachi, Pakistan) at the time of their enrolment in the study. Pregnant females and patients with secondary hypertension were excluded. Data were analyzed using SPSS version 20.0 and chi-square test was used for inferential analysis. p-values less than 0.05 were considered significant.

Results: At the end of week one, less than half of the patients achieved the desired level of BP while the majority achieved this level by the end of the study. Some 75.6% patients achieved targeted BP with Aml/Val 80/5 mg tablet, 18.5% achieved targeted BP with Aml/Val 160/5 mg tablet, and 5.9% achieved the targeted BP with Aml/Val 160/10 mg tablet at the end of the eighth week. The compliance rate was 99.2% at the first week, 98.9% at the fourth week, and 99.9% at the eighth week of treatment.

Conclusion: Our study concluded that Aml/Val (Avsar) combination therapy was very effective in controlling BP among patients who were uncontrolled with other monotherapies for at least one month.

Health effects of arsenic exposure in Latin America: An overview of the past eight years of research

Studies conducted over the past eight years in Latin America (LA) have continued to produce new knowledge regarding health impacts of arsenic (As) in drinking water. We conducted a systematic review of 92 peer-reviewed English articles published between 2011 and 2018 to expand our understanding on these health effects. Majority of the LA studies on As have been conducted in Chile and Mexico. Additional data have emerged from As-exposed populations in Argentina, Bolivia, Brazil, Colombia, Ecuador, and Uruguay. The present review has documented recent data on the biomarkers of As exposure, genetic susceptibility and genotoxicity, and risk assessment to further characterize the health effects and exposed populations. Some recent findings on the associations of As with bladder and lung cancers, reproductive outcomes, and declined cognitive performance have been consistent with what we reported in our previous systematic review article. We have found highly convincing evidence of in utero As exposure as a significant risk factor for several health outcomes, particularly for bladder cancer, even at moderate level. New data have emerged regarding the associations of As with breast and laryngeal cancers as well as type 2 diabetes. We observed early life As exposure to be associated with kidney injury, carotid intima-media thickness, and various pulmonary outcomes in children. Other childhood effects such as low birth weight, low gestational age, anemia, increased apoptosis, and decreased cognitive functions were also reported. Studies identified genetic variants of As methyltransferase that could determine susceptibility to As related health outcomes. Arsenic-induced DNA damage and alteration of gene and protein expression have also been reported. While the scope of research is still vast, the substantial work done on As exposure and its health effects in LA will help direct further large-scale studies for more comprehensive knowledge and plan appropriate mitigation strategies.

Perceptions, Beliefs, and Attitudes Toward Various Hearing Conservation Approaches Reported by Indiana College Agriculture Students

Highlights

Abstract. Noise-induced hearing loss is a major public health challenge for agricultural communities. However, there is limited hearing conservation research addressing the issue, especially for youth and young adults. The purpose of this study was to investigate the perceptions and practices of Indiana undergraduate students who lived or worked on a farm. The students were asked to rank the most common and current hearing conservation educational approaches, including in-person classroom presentation, mailers, and technology-based approaches, i.e., computer-based training, interactive websites, static websites, and smartphone noise-measuring applications (apps). A total of 91 undergraduate students enrolled in agriculture classes at four Indiana higher educational institutions participated in the study. They completed a sociodemographic and farm activity survey, followed by a 30-minute in-person presentation on hearing health conservation. After the presentation, each participant completed a questionnaire that included items about their perceptions of the feasibility, sustainability, rankings, and preferences of the various educational approaches discussed in the presentation. Participants ranked the noise-measuring app and in-person classroom presentation as their most preferred educational approaches for hearing conservation (39% and 28%, respectively). They identified multiple features of these two intervention approaches as beneficial. Sixty-four percent of participants indicated that a combination of approaches could influence hearing protection use and should include in-person classroom presentation and one of the technology-based approaches (noise-measuring apps, 37.3%). These findings are expected to assist health interventionists and program designers in developing future hearing protection education programs for farm youth, who may otherwise lack access to resources for preventing premature hearing loss due to loud noise exposure. Keywords: Agricultural workers, Hearing conservation, Hearing protection, Undergraduate college students, Youth education.

Investigation of a New Spectrophotometric Method for the Analysis of Ciprofloxacin Based on Microwave Assisted Diazotization

A microwave-assisted diazotization reaction of ciprofloxacin was used for the analysis of ciprofloxacin in pharmaceutical samples. The ciprofloxacin was diazotized with phenol using acidified sodium nitrite in a domestic microwave oven. Faster microwave heating and microwave effects were found to be very effective for the process of diazotization. The microwave-assisted reaction was initiated in an acidic media and the colored product was stabilized in a slightly basic medium using a NaOH solution as a neutralizer. The product was found to exhibit the maximum absorbance at 440 nm. All of the experimental conditions like the concentration of reagents, microwave power and reaction time were optimized. The optimum concentrations for phenol, sodium nitrite, HCl and NaOH were found to be 140 ppm, 300 ppm, 0.006 M and 0.006 M respectively. The optimum reaction time was found to be 2 min and a medium high power of the microwave was found to be most effective. The limit of detection (LOD) and the limit of quantification (LOQ) were found to be 1.08 and 3.61 mg L^-1 respectively. The developed method was successfully applied for the determination of ciprofloxacin in pharmaceutical samples. This new spectrophotometric method for the analysis of ciprofloxacin is fast, sensitive, easy and cost effective.

Thyroid hormones and neurobehavioral functions among adolescents chronically exposed to groundwater with geogenic arsenic in Bangladesh

Groundwater, the major source of drinking water in Bengal Delta Plain, is contaminated with geogenic arsenic (As) enrichment affecting millions of people. Children exposed to tubewell water containing As may be associated with thyroid dysfunction, which in turn may impact neurodevelopmental outcomes. However, data to support such relationship is sparse. The purpose of this study was to examine if chronic water As (WAs) from Holocene alluvial aquifers in this region was associated with serum thyroid hormone (TH) and if TH biomarkers were related to neurobehavioral (NB) performance in a group of adolescents. A sample of 32 healthy adolescents were randomly drawn from a child cohort in the Health Effects of Arsenic Longitudinal Study (HEALS) in Araihazar, Bangladesh. Half of these participants were consistently exposed to low WAs (<10 μg/L) and the remaining half had high WAs exposure (≥10 μg/L) since birth. Measurements included serum total triiodothyronine (tT₃), free thyroxine (fT₄), thyrotropin (TSH) and thyroperoxidase antibodies (TPOAb); concurrent WAs and urinary arsenic (UAs); and adolescents' NB performance. WAs and UAs were positively and significantly correlated with TPOAb but were not correlated with TSH, tT₃ and fT₄. After accounting for covariates, both WAs and UAs demonstrated positive but non-significant relationships with TSH and TPOAb and negative but non-significant relationships with tT₃ and fT₄. TPOAb was significantly associated with reduced NB performance indicated by positive associations with latencies in simple reaction time (b = 82.58; p < 0.001) and symbol digit (b = 276.85; p = 0.005) tests. TSH was significantly and negatively associated with match-to-sample correct count (b = -0.95; p = 0.05). Overall, we did not observe significant associations between arsenic exposure and TH biomarkers although the relationships were in the expected directions. We observed TH biomarkers to be related to reduced NB performance as hypothesized. Our study indicated a possible mechanism of As-induced neurotoxicity, which requires further investigations for confirmatory findings.

Long-term survival in visceral transplant recipients in the new era: A single-center experience

There is a paucity of data on long-term outcomes following visceral transplantation in the contemporary era. This is a single-center retrospective analysis of all visceral allograft recipients who underwent transplant between November 2003 and December 2013 with at least 3-year follow-up data. Clinical data from a prospectively maintained database were used to assess outcomes including patient and graft survival. Of 174 recipients, 90 were adults and 84 were pediatric patients. Types of visceral transplants were isolated intestinal transplant (56.3%), combined liver-intestinal transplant (25.3%), multivisceral transplant (16.1%), and modified multivisceral transplant (2.3%). Three-, 5-, and 10-year overall patient survival was 69.5%, 66%, and 63%, respectively, while 3-, 5-, and 10-year overall graft survival was 67%, 62%, and 61%, respectively. In multivariable analysis, significant predictors of survival included pediatric recipient (P = .001), donor/recipient weight ratio <0.9 (P = .008), no episodes of severe acute rejection (P = .021), cold ischemia time <8 hours (P = .014), and shorter hospital stay (P = .0001). In conclusion, visceral transplantation remains a good option for treatment of end-stage intestinal failure with parenteral nutritional complications. Proper graft selection, shorter cold ischemia time, and improvement of immunosuppression regimens could significantly improve the long-term survival.

2-Mercapto Benzothiazole Derivatives: As Potential Leads for the Diabetic Management

BACKGROUND

Results of our previous studies on antiglycation activity, and the noncytotoxicity of 2-mercapto benzothiazoles, encouraged us to further widen our investigation towards the identification of leads against diabetes mellitus.

METHODS

33 derivatives of 2-mercapto benzothiazoles 1-33 were evaluated for in vitro α- glucosidase inhibitory activity. Mode of inhibition was deduced by kinetic studies. To predict the interactions of 2-mercapto benzothiazole derivatives 1-33 with the binding pocket of α-glucosidase enzyme, molecular docking studies were performed on the selected inhibitors.

RESULTS

Compounds 2-4, 6-7, 9-26, 28 and 30 showed many folds potent α-glucosidase inhibitory activity in the range of IC50 = 31.21-208.63 μM, as compared to the standard drug acarbose (IC50 = 875.75 ± 2.08 μM). It was important to note that except derivative 28, all other derivatives were also found previously to have antiglycating potential in the range of IC50 = 187.12-707.21 μM.

CONCLUSION

A number of compounds were identified as dual nature as antiglycating agent and α- glucosidase inhibitors. These compounds may serve as potential lead candidates for the management of diabetes mellitus.

Synthesis of β-Ketosulfone Derivatives As New Non-Cytotoxic Urease Inhibitors In Vitro

BACKGROUND

Peptic ulcer and urolithiasis are largely due to infection caused by ureaseproducing bacteria. Therefore, the discovery of urease inhibitors is an important area of medicinal chemistry research.

OBJECTIVE

The main aim of the work was to identify novel urease inhibitors with no cytotoxicity.

METHODS

During the current study, a series of β-ketosulfones 1-26 was synthesized in two steps and evaluated for their in vitro urease inhibition potential.

RESULTS

Out of twenty-six compounds, seventeen have shown good to significant urease inhibitory activity with IC50 values ranging between 49.93-351.46 µM, in comparison to standard thiourea (IC50 = 21 ± 0.11 µM). Moreover, all compounds found to be non-cytotoxic against normal 3T3 cell line.

CONCLUSION

This study has identified β-ketosulfones as novel and non-cytotoxic urease inhibitors.

Memantine Is Protective against Cytotoxicity Caused by Lead and Quinolinic Acid in Cultured Rat Embryonic Hippocampal Cells

Quinolinic acid (QA) is an excitotoxic metabolite of the kynurenine pathway of tryptophan metabolism produced in response to inflammation and oxidative stress. Lead (Pb) causes oxidative stress and thus may produce neurotoxicity by increasing QA production. We investigated the in vitro cytotoxic effects of Pb and QA and the protective effects of the NMDA receptor antagonist memantine. Primary cultures of embryonic hippocampal cells from Wistar rats were treated with different concentrations of Pb, QA, and Pb + QA with and without memantine. Cell viability was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). Apoptosis was analyzed by flow cytometry after Annexin-V/propidium iodide staining. The numbers of immunostained neurons (with β3-Tubulin; Tuj1) and astrocytes (with glial fibrillary acidic protein) were counted. Pb at 20 μg/dL (0.97 μM) and QA at 500 nM concentrations showed significant cytotoxic effects, as evidenced by decreased cell viability, increased apoptosis, and a decrease in the number of both astrocytes and neurons. The combination of Pb and QA showed significant synergistic apoptotic effects at lower doses. Memantine (500 nM) was largely protective against the cytotoxic effects of both Pb and QA, suggesting that Pb's and QA's cytotoxicity involves NMDA receptor activation. Whereas the neuroprotection by memantine from QA-induced toxicity has been previously reported, this is the first study reporting the protection by memantine against Pb-induced cytotoxicity in cultured hippocampal cells. Protection by memantine against these neurotoxicants in vivo needs to be investigated.

Residential exposure to urban traffic is associated with the poorer neurobehavioral health of Ecuadorian schoolchildren

PURPOSE

We investigated whether chronic traffic-generated air pollution containing fine and ultrafine particulate matter is associated with reduced neurobehavioral performance and behavioral dysfunction in urban Ecuadorian schoolchildren. Also, we examined the effect of child hemoglobin and sociodemographic risk factors on these neurocognitive outcomes.

METHODS

A convenience sample of healthy children aged 8-14 years attending public schools were recruited in Quito, Ecuador. Child residential proximity to the nearest heavily trafficked road was used as a proxy for traffic-related pollutant exposure. These included high exposure (<100 m), medium exposure (100-199 m) and low exposure (≥ 200 m) from the nearest heavily trafficked road. The Behavioral Assessment and Research System (BARS), a computerized test battery assessing attention, memory, learning and motor function was used to evaluate child neurobehavioral performance. The Child Behavior Checklist (CBCL/6-18) was used to assess child behavioral dysfunction as reported by mothers. The data were analyzed using multiple linear regression.

RESULTS

Children with the highest residential exposure to traffic pollutants (< 100 m) had significantly longer latencies as measured by match to sample (b = 410.27; p = 0.01) and continuous performance (b = 37.90; p = 0.02) compared to those living ≥ 200 m away. A similar but non-significant association was observed for reaction time latency. Children living within 100 m of heavy traffic also demonstrated higher scores across all CBCL subscales although only the relationship with thought problems (p = 0.05) was statistically significant in the adjusted model.

CONCLUSION

The study findings suggest that children living within 100 m of heavy traffic appear to experience subtle neurobehavioral deficits that may result from fine and ultrafine particulate matter exposure.

New Hybrid Scaffolds based on Hydrazinyl Thiazole Substituted Coumarin; As Novel Leads of Dual Potential; In Vitro α-Amylase Inhibitory and Antioxidant (DPPH and ABTS Radical Scavenging) Activities

Background:

Despite many side effects associated, there are many drugs which are being clinically used for the treatment of type-II diabetes mellitus (DM). In this scenario, there is still need to develop new therapeutic agents with more efficacy and less side effects. By keeping in mind the diverse spectrum of biological potential associated with coumarin and thiazole, a hybrid class based on these two heterocycles was synthesized.

Method:

Hydrazinyl thiazole substituted coumarins 4-20 were synthesized via two step reaction. First step was the acid catalyzed reaction of 3-formyl/acetyl coumarin derivatives with thiosemicarbazide to form thiosemicarbazone intermediates 1-3, followed by the reaction with different phenacyl bromides to afford products 4-20. All the synthetic analogs 4-20 were characterized by different spectroscopic techniques such as EI-MS, HREI-MS, 1H-NMR and 13C-NMR. Stereochemical assignment of the iminic double bond was carried out by the NOESY experiments. Elemental analysis was found in agreement with the calculated values.

Results:

Compounds 4-20 were screened for α-amylase inhibitory activity and showed good activity in the range of IC50 = 1.829 ± 0.102-3.37 ± 0.17 µM as compared to standard acarbose (IC50 = 1.819 ± 0.19 µM). Compounds were also investigated for their DPPH and ABTS radical scavenging activities and displayed good radical scavenging potential. In addition to that molecular modelling study was conducted on all compounds to investigate the interaction details of compounds 4-20 (ligands) with active site (receptor) of enzyme.

Conclusion:

The newly identified hybrid class may serve as potential lead candidates for the management of diabetes mellitus.

Efficacy of hearing conservation education programs for youth and young adults: a systematic review

BACKGROUND

Many youth and young adults experience high noise exposure compounded by lack of access to hearing health education. Although the need for hearing health education programs is evident, the efficacy of these programs for youth is unclear. We evaluated the literature for efficacy of various hearing conservation programs aimed at youth and young adults, and analyzed their strengths and limitations.

METHODS

Studies reporting results of hearing conservation or hearing loss prevention programs with youth or young adults, using randomized controlled trials, quasi-experimental designs, experimental design, or qualitative research, and published in peer-reviewed journals in English between 2001 and 2018 were included. Studies were found through searches of selected literature databases (i.e., PubMed, Google Scholar, NIOSH Toxline, and Scopus). Identified publications were assessed for relevance, and data were extracted from the studies deemed relevant.

RESULTS

A total of 10 studies were included. Very little evidence of efficacy of hearing conservation educational programs was found in these studies. Several methodological limitations including lack of rigorous study designs, inadequate power, and application of inappropriate statistical analysis were noted. Some use of technology in programs (e.g., smartphone apps, mobile phone text messages, and computers) was observed, but conclusions as to the effectiveness of these tools were limited by the small number of studies and small sample sizes.

CONCLUSIONS

The number of studies of educational hearing conservation programs for youth and young adults was low. The efficacy of the program was not reported in most studies, and it is difficult to draw public health conclusions from these studies due to their multiple methodological limitations. While use of technology in hearing conservation educational programs offers promise, its effectiveness has not been studied.

Pancreatic cystosis in patients with cystic fibrosis: A qualitative systematic review

BACKGROUND

Patients with cystic fibrosis (CF) and a CFTR gene mutation may present with a variety of pancreatic disorders. The presence of multiple macrocysts (>1 cm) replacing the entire pancreatic parenchyma is termed pancreatic cystosis. Lack of clear data makes clinical decision making challenging and controversial. The aim of this review is to perform a qualitative systematic analysis of the literature with intention to evaluate management plans.

METHODS

Electronic databases MEDLINE, Embase, and Scopus were searched for relevant studies, and 19 studies describing patients with pancreatic cystosis were included and analyzed for clinical features and therapy offered.

RESULTS

The data of 24 patients were collected from included studies. Eight cases (33%) had a documented CFTR gene mutation and 10 (42%) were symptomatic at presentation. Imaging modalities included ultrasound in 18 (75%), CT in 12 (50%), and MRI in 8 (33%) cases. An average size of the largest cyst was 5.4 cm. 6 (25%) patients were offered therapy that described surgical (3), endoscopic (1), or medical therapy (2). Surgeries offered included total pancreatectomy, partial pancreatic resection of uncertain extent, and complex cyst resection. Endoscopic treatment was cystogastrostomy. Novel medical treatment was utilized with Doxepin, Propantheline, and Clonidine, resulting in reduction in cyst size and overall clinical improvement.

CONCLUSION

Patients with pancreatic cystosis should not be denied treatment when necessary. This literature review is the most comprehensive thus far of cystic fibrosis and pancreatic cystosis, and it did not provide identification of a definitive treatment plan or demonstrate contraindication to specific therapies.

Intraventricular infusion of quinolinic acid impairs spatial learning and memory in young rats: a novel mechanism of lead-induced neurotoxicity

Background

Lead (Pb), a heavy metal, and quinolinic acid (QA), a metabolite of the kynurenine pathway of tryptophan metabolism, are known neurotoxicants. Both Pb and QA impair spatial learning and memory. Pb activates astrocytes and microglia, which in turn induce the synthesis of QA. We hypothesized increased QA production in response to Pb exposure as a novel mechanism of Pb-neurotoxicity.

Methods

Two experimental paradigms were used. In experiment one, Wistar rat pups were exposed to Pb via their dams’ drinking water from postnatal day 1 to 21. Control group was given regular water. In the second protocol, QA (9 mM) or normal saline (as Vehicle Control) was infused into right lateral ventricle of 21-day old rats for 7 days using osmotic pumps. Learning and memory were assessed by Morris water maze test on postnatal day 30 or 45 in both Pb- and QA-exposed rats. QA levels in the Pb exposed rats were measured in blood by ELISA and in the brain by immunohistochemistry on postnatal days 45 and 60. Expression of various molecules involved in learning and memory was analyzed by Western blot. Means of control and experimental groups were compared with two-way repeated measure ANOVA (learning) and t test (all other variables).

Results

Pb exposure increased QA level in the blood (by ~ 58%) and increased (p < 0.05) the number of QA-immunoreactive cells in the cortex, and CA1, CA3 and dentate gyrus regions of the hippocampus, compared to control rats. In separate experiments, QA infusion impaired learning and short-term memory similar to Pb. PSD-95, PP1, and PP2A were decreased (p < 0.05) in the QA-infused rats, whereas tau phosphorylation was increased, compared to vehicle infused rats.

Conclusion

Putting together the results of the two experimental paradigms, we propose that increased QA production in response to Pb exposure is a novel mechanism of Pb-induced neurotoxicity.

Synthesis, Molecular Modeling and Biological Evaluation of 5-arylidene-N,N-diethylthiobarbiturates as Potential α-glucosidase Inhibitors

BACKGROUND

Barbituric acid derivatives are a versatile group of compounds which are identified as potential pharmacophores for the treatment of anxiety, epilepsy and other psychiatric disorders. They are also used as anesthetics and have sound effects on the motor and sensory functions. Barbiturates are malonylurea derivatives with a variety of substituents at C-5 position showing resemblance with nitrogen and sulfur containing compounds like thiouracil which exhibited potent anticancer and antiviral activities. Recently, barbituric acid derivatives have also received great interest for applications in nanoscience.

OBJECTIVE

Synthesis of 5-arylidene-N,N-diethylthiobarbiturates, biological evaluation as potential α-glucosidase inhibitors and molecular modeling.

METHODS

In the present study, N,N-Diethylthiobarbituric acid derivatives were synthesized by refluxing of N,N-diethylthiobarbituric acid and different aromatic aldehydes in distilled water. In a typical reaction; a mixture of N,N-diethylthiobarbituric acid 0.20 g (1 mmol) and 5-bromo-2- hydroxybenzaldehyde 0.199 g (1 mmol) mixed in 10 mL distilled water and reflux for 30 minutes. After completion of the reaction, the corresponding product 1 was filtered and dried and yield calculated. It was crystallized from ethanol. The structures of synthesized compounds 1-25 were carried out by using 1H, 13C NMR, EI spectroscopy and CHN analysis used for the determination of their structures. The α-glucosidase inhibition assay was performed as given by Chapdelaine et al., with slight modifications and optimization.

RESULTS

Our newly synthesized compounds showed a varying degree of α-glucosidase inhibition and at least four of them were found as potent inhibitors. Compounds 6, 5, 17, 11 exhibited IC50 values (Mean±SEM) of 0.0006 ± 0.0002, 18.91 ± 0.005, 19.18 ± 0.002, 36.91 ± 0.003 µM, respectively, as compared to standard acarbose (IC50, 38.25 ± 0.12 µM).

CONCLUSION

Our present study has shown that compounds 6, 5, 17, 11 exhibited IC50 values of 0.0006 ± 0.0002, 18.91 ± 0.005, 19.18 ± 0.002, 36.91 ± 0.003 µM, respectively. The studies were supported by in silico data analysis.

Anthranilic Acid Derivatives: Novel Inhibitors of Protein Glycation and the Associated Oxidative Stress in the Hepatocytes

BACKGROUND

Anthranilic acid derivatives are important pharmacophores in drug discovery. Several of them are currently being used, such as mefenamic acid and meclofenamates, possess analgesic, anti-inflammatory and antipyretic activities. Some anthranilic acid-based scaffolds have also been reported for the management of metabolic disorders.

OBJECTIVES

The aim of the current study was to investigate the antiglycation potential of 2-anilino benzoic acid derivatives against (N-phenylanthranilic acid) fructose- human serum albumin (HSA) glycation. The study also analyzed the effects of newly identified antiglycation inhibitors on AGEs-mediated intracellular reactive oxygen species production, and associated impaired proliferation of the hepatocytes.

METHODS

The present study focuses on the antiglycation activity of 2- anilinobenzoic acid derivatives 1-18 in in-vitro human serum albumin (HSA)- fructose model. These derivatives were also identified as non-toxic to 3T3 mouse fibroblast cell-line using metabolic assay. The effect of the most promising derivative 1, 2- (2, 4- dinitroanilino)benzoic acid, was studied in a dose dependent manner, co-incubated with fructose-derived AGEs (0- 200 μg/mL), on rat hepatocytes proliferation and associated intracellular generation of ROS via MTT assay and DCFH-DA technique, respectively.

RESULTS

We found that derivative 1 ameliorates the elevated intracellular oxidative stress and associated diminished proliferation of the hepatocytes in response to AGEs.

CONCLUSION

In conclusion, we identify novel 2- anilino benzoic acid derivatives as antiglycation agents through in-vitro and cellular-based models.