Synthesis and evaluation of pentacyclic triterpenoids conjugates as novel HBV entry inhibitors targeting NTCP receptor

Chronic liver diseases caused by hepatitis B virus (HBV) are the accepted main cause leading to liver cirrhosis, hepatic fibrosis, and hepatic carcinoma. Sodium taurocholate cotransporting polypeptide (NTCP), a specific membrane receptor of hepatocytes for triggering HBV infection, is a promising target against HBV entry. In this study, pentacyclic triterpenoids (PTs) including glycyrrhetinic acid (GA), oleanolic acid (OA), ursolic acid (UA) and betulinic acid (BA) were modified via molecular hybridization with podophyllotoxin respectively, and resulted in thirty-two novel conjugates. The anti-HBV activities of conjugates were evaluated in HepG2.2.15 cells. The results showed that 66% of the conjugates exhibited lower toxicity to the host cells and had significant inhibitory effects on the two HBV antigens, especially HBsAg. Notably, the compounds BA-PPT1, BA-PPT3, BA-PPT4, and UA-PPT3 not only inhibited the secretion of HBsAg but also suppressed HBV DNA replication. A significant difference in the binding of active conjugates to NTCP compared to the HBV PreS1 antigen was observed by SPR assays. The mechanism of action was found to be the competitive binding of these compounds to the NTCP 157-165 epitopes, blocking HBV entry into host cells. Molecular docking results indicated that BA-PPT3 interacted with the amino acid residues of the target protein mainly through π-cation, hydrogen bond and hydrophobic interaction, suggesting its potential as a promising HBV entry inhibitor targeting the NTCP receptor.

Tuning the optoelectronic properties of selenophene-diketopyrrolopyrrole-based non-fullerene acceptor to obtain efficient organic solar cells through end-capped modification

With the goal of developing a high-performance organic solar cell, nine molecules of A2-D-A1-D-A2 type are originated in the current investigation. The optoelectronic properties of all the proposed compounds are examined by employing the DFT approach and the B3LYP functional with a 6-31G (d, p) basis set. By substituting the terminal moieties of reference molecule with newly proposed acceptor groups, several optoelectronic and photovoltaic characteristics of OSCs have been studied, which are improved to a significant level when compared with reference molecule, i.e., absorption properties, excitation energy, exciton binding energy, band gap, oscillator strength, electrostatic potential, light-harvesting efficiency, transition density matrix, open-circuit voltage, fill factor, density of states and interaction coefficient. All the newly developed molecules (P1-P9) have improved λmax, small band gap, high oscillator strengths, and low excitation energies compared to the reference molecule. Among all the studied compounds, P9 possesses the least binding energy (0.24 eV), P8 has high interaction coefficient (0.70842), P3 has improved electron mobility due to the least electron reorganization energy (λe = 0.009182 eV), and P5 illustrates high light-harvesting efficiency (0.7180). P8 and P9 displayed better Voc results (1.32 eV and 1.33 eV, respectively) and FF (0.9049 and 0.9055, respectively). Likewise, the phenomenon of charge transfer in the PTB7-Th/P1 blend seems to be a marvelous attempt to introduce them in organic photovoltaics. Consequently, the outcomes of these parameters demonstrate that adding new acceptors to reference molecule is substantial for the breakthrough development of organic solar cells (OSCs).

Structural modification of A-C-A configured X-PCIC acceptor molecule for efficient photovoltaic properties with low energy loss in organic solar cells

Modification of terminal acceptors of non-fullerene organic solar cell molecule with different terminal acceptors can help in screening of molecules to develop organic photovoltaic cells with improved performance. Thus, in this work, seven new molecules with an unfused core have been designed and thoroughly investigated. DFT/TD-DFT simulations were performed on studied molecules to explore the ground and excited state characteristics. UV-Visible analysis revealed the red shift in the absorption spectrum (reaching 781 nm) owing to their smaller energy gap up to 1.94 eV. Furthermore, transition density matrix analysis demonstrated that peripheral acceptors extract the electron density from the core effectively. The effectiveness of our investigated molecules as materials for high-performing organic photovoltaic cells has been shown by an examination of their electron and hole mobilities for fast charge transfer. When combined with PTB7-Th, all molecules displayed high open circuit voltage. XP5 molecule exhibited highest open circuit voltage (1.70 eV) and lowest energy loss of 0.30 eV. All designed molecules exhibit the improved aforementioned parameters, which shows that these molecules can be used to develop competent solar devices in future.

Systematic appraisals of naturally occurring alkaloids from medicinal plants

Alkaloids are a complex class of biologically active compounds with a broad spectrum of health-related applications. Particularly the alkaloids of indole, steroidal, terpenoids, isoquinoline, and bisbenzylisoquinoline have been extensively investigated. Ultimately, substantial advancement has been highlighted in the investigation of chemical constituents and the therapeutic benefits of plant alkaloids, particularly during the last ten years. A total of 386 alkaloids have been isolated from over 40 families, including Apocynaceae, Annonaceae, Rubiaceae, Menispermaceae, Ranunculaceae, Buxaceae, Papaveraceae, Magnoliaceae, Rutaceae and Phyllanthaceae. This paper will investigate several alkaloids that have been isolated from botanical medicines as well as offer an in-depth analysis of their cytotoxic properties.

Assessing the gas sensing capability of undoped and doped aluminum nitride nanotubes

CONTEXT

CO2 and CO gas sensors are very important to recognize the insulation situation of electrical tools. ToCO explore the application of noble metal doped of aluminum nitride nanotubes for gas sensors, DFT computations according to the first principal theory were applied to study sensitivity, adsorption attributes, and electronic manner. In this investigation, platinum-doped aluminum nitride nanotubes were offered for the first time to analyze the adsorption towards CO2 and CO gases. Firm construction of platinum-doped aluminum nitride nanotubes (Pt-AlNNT) was investigated in four feasible places, and the binding energy of firm construction is 1.314 eV. Respectively, the adsorption energy between the CO2 and Pt-AlNNT systems was - 2.107 eV, while for instance of CO, the adsorption energy was - 3.258 eV. The mentioned analysis and computations are considerable for studying Pt-AlNNT as a new CO2 and CO gas sensor for electrical tools insulation. The current study revealed that the Pt-AlNNT possesses high selectivity and sensitivity towards CO2 and CO.

METHODS

In this research, Pt-doped AlNNT (Pt-AlNNT) has been studied as sensing materials of CO and CO2 for the first time. The adsorption process of Pt-AlNNT has been computed and analyzed through the DFT approach. DFT computations by using B3LYP functional and 6-31 + G* basis sets have been applied in the GAMESS code for sensing attributes, which contribute to potential applications.

Association of air pollution with risk and severity of obstructive sleep apnea: A systematic review and meta-analysis

BACKGROUND

Obstructive Sleep Apnea (OSA) is a significant health concern characterized by recurrent upper airway blockages during sleep, causing various health issues. There's growing evidence of a link between air pollution and OSA, though research results have been inconsistent. This systematic review and meta-analysis aims to consolidate and examine data on the relationship between air pollution and OSA's risk and severity.

METHODS

A literature search across PubMed, EMBASE, and Web of Science was conducted until January 10, 2024. The selection criteria targeted studies involving OSA participants or those at risk, with quantitative air pollution assessments. The Nested Knowledge software facilitated screening and data extraction, while the Newcastle-Ottawa Scale was used for quality assessment. Meta-analyses, utilizing random-effects models, computed pooled odds ratios (ORs) for the OSA risk associated with PM2.5 and NO2 exposure, analyzed using R software version 4.3.

RESULTS

The systematic review included twelve studies, four of which were analyzed in the meta-analysis. The meta-analysis revealed diverse results on the association of PM2.5 and NO2 with OSA risk. PM2.5 exposure showed a pooled OR of 0.987 (95 % CI: 0.836-1.138), indicating no substantial overall impact on OSA risk. Conversely, NO2 exposure was linked to a pooled OR of 1.095 (95 % CI: 0.920-1.270), a non-significant increase in risk. Many studies found a relationship between air pollution exposure and elevated Apnea-Hypopnea Index (AHI) levels, indicating a relationship between air pollution and OSA severity.

CONCLUSION

The findings suggest air pollutants, especially NO2, might play a role in worsening OSA risk and severity, but the evidence isn't definitive. This highlights the variability of different pollutants' effects and the necessity for more research. Understanding these links is vital for shaping public health policies and clinical approaches to address OSA amidst high air pollution.

Surgical interventions for intractable migraine: a systematic review and meta-analysis

BACKGROUND

Migraine affects approximately 14-15% of the global population, contributing to nearly 5% of the world's health burden. When drug treatments prove ineffective for intractable migraines, highly specific surgical interventions emerge as potential solutions. We aimed to analyze surgical approaches for these refractory or intractable migraines through a systematic review and meta-analysis.

METHODS

We conducted a literature search across databases such as PubMed, Scopus, Web of Science, and Embase, focusing on studies related to migraines and surgical outcomes. We considered clinical trials or observational studies that included any surgical intervention for refractory or intractable migraines, emphasizing key outcomes such as reductions in migraine intensity, Migraine Disability Assessment scores (MIDAS), and 50% Migraine Headache Index (MHI) reduction rates. Statistical analyses were performed using R version 4.3.

RESULTS

Eleven studies were included in the systematic review. A meta-analysis of four studies involving overall 95 patients showed a significant reduction in mean migraine intensity scores using ONS (-2.27, 95% CI: -3.92 to -0.63, P=0.021). Three studies with 85 patients showed an average MIDAS score reduction of -52.3, though this was not statistically significant (95% CI: -136.85 to 32.19, P=0.116). Two additional studies corroborated these reductions in MIDAS scores. Nerve decompression surgery showed a substantial decrease in the average migraine intensity (from 8.31 down to 4.06). Median MIDAS score dropped from 57 to 20. Two studies indicated a success rate of 40% and 82%, respectively, in achieving a 50% reduction in the Migraine MHI through nerve decompression. Findings from two studies suggest that septorhinoplasty and sinus surgery effectively decrease migraine intensity scores.

CONCLUSION

The existing evidence emphasizes the potential advantages of surgical interventions as a promising approach to managing intractable or refractory migraines. However, robust and comprehensive research is crucial to refine and solidify the efficacy of these surgical methods, aiming for widespread benefits for patients, considering cost-effectiveness factors.

End-capped engineering of Quinoxaline core-based non-fullerene acceptor materials with improved power conversion efficiency

Improving the light-harvesting efficiency and boosting open circuit voltage are crucial challenges for enhancing the efficiency of organic solar cells. This work introduces seven new molecules (SA1-SA7) to upgrade the optoelectronic and photovoltaic properties of Q-C-F molecule-based solar cells. All recently designed molecules have the same alkyl-substituted Quinoxaline core and CPDT donor but vary in the end-capped acceptor subunits. All the investigated molecules have revealed superior properties than the model (R) by having absorbance ranging from 681 nm to 782 nm in the gaseous medium while 726 nm-861 nm in chloroform solvent, with the lowest band gap ranging from 1.91 to 2.19 eV SA1 molecule demonstrated the highest λmax (861 nm) in chloroform solvent and the lowest band gap (1.91 eV). SA2 molecule has manifested highest dipole moment (4.5089 D), lower exciton binding energy in gaseous (0.33 eV) and chloroform solvent (0.47 eV), and lower charge mobility of hole (0.0077693) and electron (0.0042470). At the same time, SA7 showed the highest open circuit voltage (1.56 eV) and fill factor (0.9166) due to solid electron-pulling acceptor moieties. From these supportive outcomes, it is inferred that our computationally investigated molecules may be promising candidates to be used in advanced versions of OSCs in the upcoming period.

Osseous implications of proton pump inhibitor therapy: An umbrella review

Background

Proton pump inhibitors (PPIs) are among the most commonly prescribed medications worldwide for acid-related disorders. While their short-term efficacy and safety are well-established, concerns regarding their long-term effects on bone health have emerged. This umbrella review aimed to synthesize the available findings on the associations between PPI use and bone metabolism outcomes.

Methods

An electronic search was conducted using PubMed, Web of Science, Embase, and the Cochrane Database up to September 16, 2023. Systematic reviews and meta-analyses of randomized controlled trials (RCTs) and observational studies that evaluated the relationship between PPIs and bone metabolism outcomes were included. Data extraction, quality appraisal, and synthesis were performed in line with the Joanna Briggs Institute and PRISMA guidelines. The strength of the evidence was graded using the GRADE criteria. Statistical analysis was performed in R version 4.3.

Results

Out of 299 records, 27 studies met the inclusion criteria. The evidence indicated a statistically significant increased risk of fractures, notably hip, spine, and wrist fractures, in PPI users. PPI use was associated with changes in Bone Mineral Density (BMD) across various bones, though the clinical relevance of these changes remains uncertain. Furthermore, PPI-induced hypomagnesemia, which can influence bone health, was identified. A notable finding was the increased risk of dental implant failures in PPI users. However, the certainty of most of the evidence ranged from very low to low based on GRADE criteria.

Conclusion

The long-term use of PPIs may be associated with adverse bone health outcomes, including increased fracture risk, alterations in BMD, hypomagnesemia, and dental implant failure. While these findings highlight potential concerns for long-term PPI users, the current evidence's low certainty underscores the need for robust, high-quality research to clarify these associations.

A systematic review on Nb2O5-based photocatalysts: Crystallography, synthetic methods, design strategies, and photocatalytic mechanisms

With the increasing popularity of photocatalytic technology and the highly growing issues of energy scarcity and environmental pollution, there is an increasing interest in extremely efficient photocatalytic systems. The widespread immense attention and applicability of Nb2O5 photocatalysts can be attributed to their multiple benefits, including strong redox potentials, non-toxicity, earth abundance, corrosion resistance, and efficient thermal and chemical stability. However, the large-scale application of Nb2O5 is currently impeded by the barriers of rapid recombination loss of photo-activated electron/hole pairs and the inadequacy of visible light absorption. To overcome these constraints, plentiful design strategies have been directed at modulating the morphology, electronic band structure, and optical properties of Nb2O5. The current review offers an extensive analysis of Nb2O5-based photocatalysts, with a particular emphasis on crystallography, synthetic methods, design strategies, and photocatalytic mechanisms. Finally, an outline of future research directions and challenges in developing Nb2O5-based materials with excellent photocatalytic performance is presented.

Alarming Rise in Global Rabies Cases Calls for Urgent Attention: Current Vaccination Status and Suggested Key Countermeasures

In the wake of rising rabies cases worldwide, especially after the COVID-19 pandemic, it is time to understand the scenario better and suggest technically sound and plausible countermeasures. This article is an attempt at this perspective. Although a critical zoonotic viral disease, rabies is preventable. Medico-legally, the ailment is classified as furious rabies and paralytic rabies. The four world bodies, namely, the World Health Organisation (WHO), the Food and Agriculture Organisation (FAO), the World Organisation for Animal Health (OIE), and the Global Alliance for Rabies Control (GARC) endorsed framing a global support system to eradicate human death from dog-mediated rabies under the 'Zero by 30' framework. The framework calls for extending the vaccination of dogs to reduce the risk of human rabies. Stray dogs became aggressive primarily due to their food shortage during the pandemic lockdown. As many adopted stray dogs were disowned post-pandemic, decreased human-dog interactions increased the aggressiveness among dogs. As a result, 'dog-bite' cases rose, with a sudden spike in rabies cases and dog-bite-induced deaths in India and elsewhere. Jeopardising the 'Zero by 30' plan is certainly a public health concern. Stray dog sterilisation through the irreversible ductal occlusion technique and reversible inhibition of sperm under guidance (RISUG) are other suggested interventions to control rabies. Importantly, wildlife like foxes, raccoons, skunks, and bats could also be rabid. Three out of the four WHO-pre-qualified human vaccines against rabies are intradermally administered as post-exposure prophylaxis, while the intramuscular one is more popular. Even though 'Zero by 30' may not be achieved within the set timeframe, it is time for a concerted and planned strategy by global agencies to curb the globally rising rabies cases and manage the disease better. The 'One Health' model seems to be a plausible guideline and the ultimate countermeasure to achieve this.

SARS-CoV-2 Variants BA.2.86 and EG.5.1 Alongside Scrub Typhus and Nipah in India During the Ongoing Cricket World Cup 2023: Threat Perceptions and Countermeasures

The United States (US), the United Kingdom (UK), and China witnessed rising cases of coronavirus disease 2019 (COVID-19) in 2023. Concerns about severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) novel strains amid the sudden surge of COVID cases are growing. Recently, BA.2.86 (Pirola) poses a much greater risk due to its higher transmission rate and spreading across regions. Pirola variant has mutations that set it apart from all earlier known SARS-CoV-2 variants. This variant was designated a variant of interest by the World Health Organization (WHO). Another SARS-CoV-2 variant named "Eris" (EG.5.1) was detected in India and started picking up in the US and the UK. The WHO listed EG.5.1 (variant) as a variant under monitoring. Therefore, it is important to remain vigilant. Further, multiple Nipah virus infections and scrub typhus cases are spreading among humans in India currently. In this situation, the 13th edition of the International Cricket Council (ICC) Men's Cricket World Cup is being held in India this year. With global reach, this big sporting carnival attracts millions of cricket fans from several countries. In light of the multiple public health concerns encountered currently, this gala global sports event needs additional preventive measures.

Deep and Transfer Learning Approaches for Automated Early Detection of Monkeypox (Mpox) Alongside Other Similar Skin Lesions and Their Classification

The world faces multiple public health emergencies simultaneously, such as COVID-19 and Monkeypox (mpox). mpox, from being a neglected disease, has emerged as a global threat that has spread to more than 100 nonendemic countries, even as COVID-19 has been spreading for more than 3 years now. The general mpox symptoms are similar to chickenpox and measles, thus leading to a possible misdiagnosis. This study aimed at facilitating a rapid and high-brevity mpox diagnosis. Reportedly, mpox circulates among particular groups, such as sexually promiscuous gay and bisexuals. Hence, selectively vaccinating, isolating, and treating them seems difficult due to the associated social stigma. Deep learning (DL) has great promise in image-based diagnosis and could help in error-free bulk diagnosis. The novelty proposed, the system adopted, and the methods and approaches are discussed in the article. The present work proposes the use of DL models for automated early mpox diagnosis. The performances of the proposed algorithms were evaluated using the data set available in public domain. The data set adopted for the study was meant for both training and testing, the details of which are elaborated. The performances of CNN, VGG19, ResNet 50, Inception v3, and Autoencoder algorithms were compared. It was concluded that CNN, VGG19, and Inception v3 could help in early detection of mpox skin lesions, and Inception v3 returned the best (96.56%) classification accuracy.

Current Surge of Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) Variants in China Could Be Threatening as the Asian Games 2023 Flags Off in September: Foolproof Cautionary Measures Are Suggested

Despite normalcy having almost returned in the lives of people throughout the world post-coronavirus disease-19 (COVID-19) pandemic caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), the danger still looms over the fears of development and propagation of a newer SARS-CoV-2 variant. The movement of people globally has reached the pre-pandemic level, and this augmentation increased surveillance regarding the emergence of lethal SARS-CoV-2 variants. International sports events are among the potential avenues where the virus could cause serious impact. Therefore, the organization of such events should be planned and executed meticulously to avoid viral transmission and minimize the health effects of infections on the sportspersons and the local people. Additionally, there could be dissemination of the infections to the native countries of the participants and visitors while they return to their homes. Through this editorial, we prompt caution to the organizers and the event-hosting nation's administration regarding the potential threat and suggest measures to avoid any medical emergencies related to COVID-19.

Nanoadjuvants: Promising Bioinspired and Biomimetic Approaches in Vaccine Innovation

Adjuvants are the important part of vaccine manufacturing as they elicit the vaccination effect and enhance the durability of the immune response through controlled release. In light of this, nanoadjuvants have shown unique broad spectrum advantages. As nanoparticles (NPs) based vaccines are fast-acting and better in terms of safety and usability parameters as compared to traditional vaccines, they have attracted the attention of researchers. A vaccine nanocarrier is another interesting and promising area for the development of next-generation vaccines for prophylaxis. This review looks at the various nanoadjuvants and their structure-function relationships. It compiles the state-of-art literature on numerous nanoadjuvants to help domain researchers orient their understanding and extend their endeavors in vaccines research and development.

The challenges of open data for future epidemic preparedness: The experience of the 2022 Ebolavirus outbreak in Uganda

On 20 September 2022, the Ministry of Health in Uganda, together with the World Health Organization-Regional Office for Africa (WHO AFRO) confirmed an outbreak of EVD due to Sudan ebolavirus in Mubende District, after one fatal case was confirmed. Real-time information are needed to provide crucial information to understand transmissibility, risk of geographical spread, routes of transmission, risk factors of infection, and provide the basis for epidemiological modelling that can inform response and containment planning to reduce the burden of disease. We made an effort to build a centralized repository of the Ebola virus cases from verified sources, providing information on dates of symptom onset, locations (aggregated to the district level), and when available, the gender and status of hospitals, reporting bed capacity and isolation unit occupancy rate according to the severity status of the patient. The proposed data repository provides researchers and policymakers timely, complete, and easy-accessible data to monitor the most recent trends of the Ebola outbreak in Ugandan districts with informative graphical outputs. This favors a rapid global response to the disease, enabling governments to prioritize and adjust their decisions quickly and effectively in response to the rapidly evolving emergency, with a solid data basis.

Synthesis and antitumor activity of new tetrahydrocurcumin derivatives via click reaction

Three new derivatives of tetrahydrocurcumin 6, 7 and 9 have been prepared as potent antitumor agents using copper(II)-catalyzed 'click chemistry'. Their structures were identified using ¹H-NMR, ¹³C-NMR and HRMS techniques. MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay has been carried out to investigate the in vitro cytotoxicity against human cervical carcinoma (HeLa), human lung adenocarcinoma (A549), human hepatoma carcinoma (HepG2) and human colon carcinoma (HCT-116). Compound 6 has showed significant inhibitory activity against HCT-116 cell line with an IC₅₀ value of 17.86 μM compared to tetrahydrocurcumin (50.96 μM) and positive control etoposide (19.48 μM) while showed no inhibitory activity against NCM460 cell line. Compounds 7 showed moderate inhibitory activity compared to tetrahydrocurcumin and etoposide while compound 9 showed no obvious inhibitory activity. The results suggested further structure modifications of tetrahydrocurcumin to improve its anticancer activity.

Recent progress in chemical approaches for the development of novel neuraminidase inhibitors

Influenza virus is the main cause of an infectious disease called influenza affecting the respiratory system including the throat, nose and lungs. Neuraminidase inhibitors are reagents used to block the enzyme called neuraminidase to prevent the influenza infection from spreading. Neuraminidase inhibitors are widely used in the treatment of influenza infection, but still there is a need to develop more potent agents for the more effective treatment of influenza. Complications of the influenza disease lead to death, and one of these complications is drug resistance; hence, there is an urgent need to develop more effective agents. This review focuses on the recent advances in chemical synthesis pathways used for the development of new neuraminidase agents along with the medicinal aspects of chemically modified molecules, including the structure-activity relationship, which provides further rational designs of more active small molecules.

Dinghupeptins A-D, Chymotrypsin Inhibitory Cyclodepsipeptides Produced by a Soil-Derived Streptomyces

Four new cyclodepsipeptides, dinghupeptins A-D (1-4), possessing a rare N⁵-(2-hydroxylethyl)glutamine moiety, were isolated from cultures of the soil-derived Streptomyces sp. SC0581. Their structures were elucidated by spectroscopic and advanced Marfey's amino acid analysis, and their 3D structures were established by theoretical conformational analysis. Compounds 1 and 2, containing a 3-amino-6-hydroxypiperidone unit, displayed selective inhibition of chymotrypsin with IC₅₀ values of 2.1 and 1.1 μM, respectively. Enzyme kinetic analysis and molecular docking experiments revealed they are competitive inhibitors binding to the active site of chymotrypsin.

Synthesis and Cytotoxic Activity of Novel Tetrahydrocurcumin Derivatives Bearing Pyrazole Moiety

Tetrahydrocurcumin (THC) is a major metabolite of curcumin and plays an important role in curcumin-induced biological effects. THC is a promising preventive and chemotherapeutic agent for cancer. A series of new pyrazole derivatives of THC have been synthesized as potent anticancer agents. Direct condensation of THC with various substituted hydrazines leads to new pyrazole derivatives of THC (1-18). The prepared compounds have been evaluated via in vitro MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay for their cell proliferation-inhibitory activity against human lung adenocarcinoma (A549), human cervical carcinoma (HeLa) and human breast carcinoma (MCF-7) cells. Most derivatives show significantly higher anticancer activity against all three tested cancer cell lines than the parent compound THC. Several compounds (7, 8, 12, 13 and 15) display promising anticancer activity against MCF-7 cell line with IC₅₀ values ranging from 5.8 to 9.3 µM. The most active compound (8) is substituted with 4-bromophenyl group at the pyrazole ring and inhibits the growth of all three tested cancer cell lines with an IC₅₀ values of (8.0 µM, A549), (9.8 µM, HeLa) and (5.8 µM, MCF-7). The obtained compounds can be a good starting point for the development of new lead molecules in the fight against cancer.

Synthesis of cyclic N (1)-pentylinosine phosphate, a new structurally reduced cADPR analogue with calcium-mobilizing activity on PC12 cells

Cyclic N¹-pentylinosine monophosphate (cpIMP), a novel simplified inosine derivative of cyclic ADP-ribose (cADPR) in which the N¹-pentyl chain and the monophosphate group replace the northern ribose and the pyrophosphate moieties, respectively, was synthesized. The role played by the position of the phosphate group in the key cyclization step, which consists in the formation of a phosphodiester bond, was thoroughly investigated. We have also examined the influence of the phosphate bridge on the ability of cpIMP to mobilize Ca²⁺ in PC12 neuronal cells in comparison with the pyrophosphate bridge present in the cyclic N¹-pentylinosine diphosphate analogue (cpIDP) previously synthesized in our laboratories. The preliminary biological tests indicated that cpIMP and cpIDP induce a rapid increase of intracellular Ca²⁺ concentration in PC12 neuronal cells.

Stereoselective synthesis and molecular modeling of chiral cyclopentanes

The reaction of 3-methyseleno-2-methylselenomethyl-propene with benzyl 2,3-anhydro-4-O-triflyl-β-L-ribopyranoside provides a major convenient enantiomeric product of 1-methylene-(benzyl3,4-dideoxy-α-D-arabinopyranoso)-[3,4-c]-cyclopentane, with benzyl-2,3-anhydro-4-deoxy-4-C-(2-methyl- propen-3-yl)-α-D-lyxopyranoside as a minor product. While the reaction of 3-methyseleno-2-[methylselenomethyl]-propene with benzyl 2,3-anhydro-4-O-triflyl-α-D-ribopyranoside produces a good yield of benzyl-2,3-anhydro-4-deoxy-4-C-(2-methylpropen-3-yl)-α-D-lyxo-pyranoside. Molecular modeling and molecular dynamics simulations indicate that the intermediate in the reaction of the β-L sugar frequently occupies an optimal conformation that leads to the formation of cyclopentane, while the intermediate in the reaction of the α-D sugar has a very small probability. The results point to the dominant role of the β-L sugar intermediate in controlling the cyclopentane formation.

Inhibition of polyglutamine aggregation in R6/2 HD brain slices-complex dose-response profiles

Huntington's disease (HD) is a late onset neurodegenerative disorder caused by a CAG/polyglutamine (polyQ) repeat expansion. PolyQ aggregates can be detected in the nuclei and processes of neurons in HD patients and mouse models prior to the onset of symptoms. The misfolding and aggregation pathway is an important therapeutic target. To better test the efficacy of aggregation inhibitors, we have developed an organotypic slice culture system. We show here that the formation of polyQ aggregates in hippocampal slices established from the R6/2 mouse follows the same prescribed sequence as occurs in vivo. Using this assay, we show that Congo red and chrysamine G can modulate aggregate formation, but show complex dose-response curves. Oral administration of creatine has been shown to delay the onset of all aspects of the phenotype and neuropathology in R6/2 mice. We show here that creatine can similarly inhibit aggregate formation in the slice culture assay.

Trends in diet, nutritional status, and diet-related noncommunicable diseases in China and India: the economic costs of the nutrition transition

Undernutrition is being rapidly reduced in India and China. In both countries the diet is shifting toward higher fat and lower carbohydrate content. Distinct features are high intakes of foods from animal sources and edible oils in China, and high intakes of dairy and added sugar in India. The proportion of overweight is increasing very rapidly in China among all adults; in India the shift is most pronounced among urban residents and high-income rural residents. Hypertension and stroke are relatively higher in China and adult-onset diabetes is relatively higher in India. Established economic techniques were used to measure and project the costs of undernutrition and diet-related noncommunicable diseases in 1995 and 2025. Current WHO mortality projections of diet-related noncommunicable diseases, dietary and body composition survey data, and national data sets of hospital costs for healthcare, are used for the economic analyses. In 1995, China's costs of undernutrition and costs of diet-related noncommunicable diseases were of similar magnitude, but there will be a rapid increase in the costs and prevalence of diet-related noncommunicable diseases by 2025. By contrast with China, India's costs of undernutrition will continue to decline, but undernutrition costs did surpass overnutrition diet-related noncommunicable disease costs in 1995. India's rapid increase in diet-related noncommunicable diseases and their costs projects similar economic costs of undernutrition and overnutrition by 2025.

Centrosome disorganization in fibroblast cultures derived from R6/2 Huntington's disease (HD) transgenic mice and HD patients

Huntington's disease (HD) is a progressive neurological disorder caused by a CAG/polyglutamine repeat expansion. We have previously generated the R6/2 mouse model that expresses exon 1 of the human HD gene containing CAG repeats in excess of 150. These mice develop a progressive neurological phenotype with a rapid onset and progression. We show here that it is impossible to establish fibroblast lines from these mice at 12 weeks of age, whilst this can be achieved without difficulty at 6 and 9 weeks. Cultures derived from mice at 12 weeks contained a high frequency of dysmorphic cells, including cells with an aberrant nuclear morphology and a high frequency of micronuclei and large vacuoles. All of these features were also present in a line derived from a juvenile HD patient. Fibroblast lines derived from R6/2 mice and from HD patients were found to have a high frequency of multiple centrosomes which could account for all of the observed phenotypes including a reduced mitotic index, high frequency of aneuploidy and persistence of the midbody. We were unable to detect large insoluble polyglutamine aggregates in either the mouse or human lines. We have identified a novel progressive HD pathology that occurs in cells of non-central nervous system origin. An investigation of the pathological consequences of the HD mutation in these cells will provide insight into cellular basis of the disease.

Impaired glutamate uptake in the R6 Huntington's disease transgenic mice

Huntington's disease (HD) is a late-onset neurodegenerative disease for which the mutation is CAG/polyglutamine repeat expansion. The R6 mouse lines expressing the HD mutation develop a movement disorder that is preceded by the formation of neuronal polyglutamine aggregates. The phenotype is likely caused by a widespread neuronal dysfunction, whereas neuronal cell death occurs late and is very selective. We show that a decreased mRNA level of the major astroglial glutamate transporter (GLT1) in the striatum and cortex of these mice is accompanied by a concomitant decrease in glutamate uptake. In contrast, the expression of the glutamate transporters, GLAST and EAAC1, remain unchanged. The mRNA level of the astroglial enzyme glutamine synthetase is also decreased. These changes in expression occur prior to any evidence of neurodegeneration and suggest that a defect in astrocytic glutamate uptake may contribute to the phenotype and neuronal cell death in HD.