Nanostructured and Functional Nanomaterials for Energy Storage and Removal of Pollutants.

Nanomaterials have a long history, and people have utilized them unknowingly [...].

Incidence of biofilms among the multidrug resistant E. coli, isolated from urinary tract infections in the Nilgiris district, South India.

Multidrug resistant uropathogenic Escherichia coli (MDRUPEC) significantly correlates with recurrent, complicated, and persistent urinary tract infection (UTI). The leading cause of multidrug resistance is the ability of E. coli to form biofilms. The physiological heterogeneity, genetic incontinency, and putative events in gene expression of biofilms render them resistant to antimicrobials and the host immune system. Understanding the determinants of antimicrobial resistance and its correlation with biofilm formations will, therefore, help the development of a better strategy for treating biofilm-associated UTIs. The present study reports on the in vitro detection of biofilm formation among multidrug resistant E. coli strains isolated from urine, the major cause of communal, nosocomial, and food-borne uropathogenic UTI. This is a cross-sectional study conducted in and around Ooty, Nilgiris, India. From the 869 urine samples analyzed for UTI, 29.34% were found to be caused by E. coli. Among this about 23.92% were found to be multidrug resistant. Among the multidrug resistant E. coli isolates, 36.06% of them were potent biofilm producers. E. coli biofilms (n = 22) were resistant to the antibiotics used to treat UTI, namely, amikacin, amoxicillin, ampicillin, cefepime, cefoperazone, cefotaxime, ceftriaxone, cefuroxime, cephalotin, ciprofloxacin, co-trimoxazole, gentamicin, levofloxacin, and nalidixic acid, but sensitive to imipenem and meropenem. All the biofilm producers exhibited motility and hemaggultination but none were positive for hemolysin production. The isolated E. coli biofilms were confirmed by VITEK R2 Compact (bioMerieux, France) and 16S rRNA gene sequencing.

Sustainable Biomass-Derived Carbon Electrodes for Potassium and Aluminum Batteries: Conceptualizing the Key Parameters for Improved Performance.

The development of sustainable, safe, low-cost, high energy and density power-density energy storage devices is most needed to electrify our modern needs to reach a carbon-neutral society by ~2050. Batteries are the backbones of future sustainable energy sources for both stationary off-grid and mobile plug-in electric vehicle applications. Biomass-derived carbon materials are extensively researched as efficient and sustainable electrode/anode candidates for lithium/sodium-ion chemistries due to their well-developed tailored textures (closed pores and defects) and large microcrystalline interlayer spacing and therefore opens-up their potential applications in sustainable potassium and aluminum batteries. The main purpose of this perspective is to brief the use of biomass residues for the preparation of carbon electrodes for potassium and aluminum batteries annexed to the biomass-derived carbon physicochemical structures and their aligned electrochemical properties. In addition, we presented an outlook as well as some challenges faced in this promising area of research. We believe that this review enlightens the readers with useful insights and a reasonable understanding of issues and challenges faced in the preparation, physicochemical properties and application of biomass-derived carbon materials as anodes and cathode candidates for potassium and aluminum batteries, respectively. In addition, this review can further help material scientists to seek out novel electrode materials from different types of biomasses, which opens up new avenues in the fabrication/development of next-generation sustainable and high-energy density batteries.

Comparative evaluation of straight and curved extension dialysis catheters for continuous renal replacement therapy in dogs with acute kidney injury.

Background: A patent dual-lumen dialysis catheter is one of the basic requirements for efficient extracorporeal (EC) therapy. Aims: The objective of this study was to measure the resistance to blood flow offered by straight and curved-extension dual-lumen dialysis catheters used for continuous renal replacement therapy (CRRT). Methods: Twenty dogs suffering from acute kidney injury (AKI) were subjected to CRRT. The dogs were allocated randomly to Group-I (curved extension catheter, n=12) or Group II (straight extension catheter, n=8), based on the type of dual-lumen catheter used in CRRT. The catheter outflow and inflow pressures were recorded at blood pump speeds of 50 ml/min and 99-100 ml/min. Data were tested for normality, and differences in mean inflow and outflow catheter resistances were evaluated for statistical significance using independent samples t-tests. Results: Straight extension catheters offered lower inflow resistance than curved extension catheters at both 50 ml/min (41.50 ± 5.84 mm Hg vs. 63.75 ± 6.88 mm Hg, P=0.03) and 99-100 ml/min (63.00 ± 8.11 mm Hg vs. 86.92 ± 7.02 mm Hg, P=0.04) blood flow rates. Straight extension catheters also offered lower outflow resistance than curved catheters at 99-100 ml/min blood flow rate (-94.12 ± 7.91 mm Hg vs. -128.25 ± 7.56 mm Hg, P=0.01; the negative signs only indicate the direction of blood flow). Conclusion: These findings suggest that straight-extension dual-lumen dialysis catheters perform better than the curved model in extracorporeal renal replacement therapy by considering their lower resistance to blood flow.

Targeting of ErbB1, ErbB2, and their Dual Targeting Using Small Molecules and Natural Peptides: Blocking EGFR Cell Signaling Pathways in Cancer: A Mini-Review.

Cancer is one of the deadliest diseases involving dysregulated cell proliferation and has been the leading cause of death worldwide. The chemotherapeutic drugs currently used for treating cancer have serious drawbacks of non-specific toxicity and drug resistance. The four members of the human epidermal growth factor receptor (EGFR), namely, ErbB1/HER1, ErbB2/HER2/neu, ErbB3/HER3 and ErbB4/HER4, the trans-membrane family of tyrosine kinase receptors, are overexpressed in many types of cancers. These receptors play an important role in cell proliferation, differentiation, invasion, metastasis and angiogenesis and unregulated activation of cancer cells. Overexpression of ErbB1 and ErbB2 occurs in several types of cancers and is associated with a poor prognosis leading to resistance to ErbB1 directed therapies. Heterodimerization with ErbB2/HER2 is a potent activator of Epidermal Growth Factor Receptor-Tyrosine kinase (EGFRTK) complex than EGFR alone. Though ErbB3/HER3 can bind to a ligand, its kinase domain is devoid of catalytic activity and hence relies on its partner (ErbB2/HER2) for initiation of signals, thus, ErbB2 is involved in the activation of ErbB3. However, recent evidence reveals that ErbB1 and ErbB2 are the most important targets for cancer therapy. By inhibiting these two important kinases, the cancer cell signaling transduction pathways can be inhibited. Lapatinib and monoclonal antibodies like trastuzumab have been used for the dual inhibition of ErbB1 and ErbB2 in the treatment of various cancers. Resistance, however, develops soon. The present report reviews the investigations that have been carried out by earlier workers for targeting ErbB1, ErbB2, and both using small molecules and novel peptides that could help/facilitate researchers to design and develop better cancer chemotherapy.

Reproducibility and long-term stability of Sn doped MnO2 nanostructures: Practical photocatalytic systems and wastewater treatment applications.

Sn-doped MnO2 were synthesized as an oxidant, a mediator of maleic acid (C4H4O4) and SnCl2 as doping ingredient via a basic sol-gel reaction with KMnO4. XRD study signposts that tetragonal crystal structure of MnO2 (ICDD#44-0141) with a plane group of 12/m (87) for both pure and Sn doped MnO2 nanostructures. The photocatalyst synthesized has mesoporosity, allowing to the N2 adsorption/desorption experiments. The geometry of the materials varies from spherical shape in pristine MnO2 to a rod-like shape in Sn-MnO2, as observed in the SEM and TEM pictures. To examine optic properties and energy bandgaps topologies, UV-visible diffuse reflectance spectroscopy was applied. In visible spectrum, overall catalytic performance of Sn-doped MnO2 was tested using methyl orange and phenol as dyes. The results suggest that the optimized Sn doped MnO2 (10 wt.%) catalyst showed higher degradation efficiency (98.5%), apparent constant (0.7841 min-1) and long term permanence. For this improved charge extraction efficiency, a potential photocatalytic mechanism was proposed.

Enhancing the photocatalytic performance of surface - Treated SnO2 hierarchical nanorods against methylene blue dye under solar irradiation and biological degradation.

Surfactant -treated tin oxide (SnO2) hierarchical nanorods were successfully synthesized through hydrothermal technique. The X-ray diffraction analysis showed the prepared SnO2 possesses tetragonal rutile structure having appreciable crystallinity with crystallite sizes in the range of 110 nm-120 nm. UV-visible diffuse reflectance absorption spectra confirm that the better visible light absorption band of SnO2 hierarchical nanorods have red shift compared to the pure SnO2. Fourier transform infrared spectroscopy (FTIR) study evident that the as-prepared SnO2 nanorods encompass the characteristic bands of SnO2 nanostructures. The morphological analyses of prepared materials were performed by FESEM, which shows that hierarchal nanorods and complex nanostructures. EDX analyses disclose all the samples are composed of Sn and O elements. The photocatalytic performance of the prepared surfactant treated SnO2 hierarchical nanorods was evaluated using methylene blue (MB) dye removal under direct natural sunlight. Recycling experiment results of CTAB - SnO2 nanorods and photocatalytic reaction mechanism also discussed in detail.

Plant Based Natural Products as Quorum Sensing Inhibitors in E. Coli: A Critical Review.

The existence of multidrug-resistant (MDR) E. coli (superbugs) is a global health issue confronting humans, livestock, food processing units, and pharmaceutical industries. The quorum sensing (QS) controlling ability of the E. coli to form biofilms has become one of the important reasons for the emergence of multidrug-resistant pathogens. Quorum signaling activation and formation of biofilm lead to the emergence of antimicrobial resistance of the pathogens increasing the therapy difficult for treating bacterial diseases. There is a crucial need, therefore, to reinforce newer therapeutic designs to overcome this resistance. As the infections caused by E. coli are attributed via the QSregulated biofilm formation, easing this system by QS inhibitors is a possible strategy for treating bacterial diseases. Plant based natural products have been reported to bind to QS receptors and interrupt the QS systems of pathogens by inhibiting biofilm formation and disrupting the formed biofilms, thus minimizing the chances to develop a resistance mechanism. The present report reviews critically the QS capability of E. coli to form biofilms leading to multidrug resistant pathogens and the investigations that have been carried out so far on plant acquired natural products as QS inhibitors.

In silico screening of FDA approved drugs against ACE2 receptor: potential therapeutics to inhibit the entry of SARS-CoV-2 to human cells.

An unknown coronavirus that emerged sometime at the end of 2019 in China, the novel SARS-CoV-2, now called COVID-19, has spread all over the world. Several efforts have been made to prevent or treat this disease, though not with success. The initiation of COVID-19 viral infection involves specific binding of SARS-CoV-2 to the host surface of the receptor, ACE2. The ACE2- SARS-CoV-2 complex then gets transferred into the endosomes where the endosomal acidic proteases cleave the S protein present in SARS-CoV-2, activating its fusion and release of the viral genome. We have carried out detailed and thorough in silico studies to repurpose FDA approved compounds to inhibit human ACE2 receptor so as to prevent the viral entry. Our study reveals that five compounds show good binding to the ACE2 receptor and hence are potential candidates to interact with ACE2 and prevent it's recognition by the virus, SARS-CoV-2. Communicated by Ramaswamy H. Sarma.

Effect of Withania Somnifera on the antioxidant and neurotransmitter status in sleep deprivation induced Wistar rats.

Sleep is normally a period of relaxation and repair, important for the maintenance of physiological homeostasis and psychological balance. "Globally, millions of people experiences sleep deprivation daily". Sleep deprivation (SD) impairs cognitive functions, decreases anti-oxidative defense and induces neuronal changes. Withania somnifera (WS), commonly known as an "Indian Ginseng" has broad therapeutic applications, including anti-inflammatory activities, actions on immune system, circulatory system, central nervous system etc., The study is aimed to assess effect of Withania somnifera on antioxidant status and neurotransmitter level in sleep deprivation induced male Wistar albino rats. The study was done in the Department of Physiology, Meenakshi Medical College and Hospital, Enathur, Kanchipuram. 24 male adult Wistar rats weighing 120-150g were used for the study. They were divided into 4 groups with 6 animals in each group. (Group I - cage control, Group II - large platform control, Group III - sleep deprived group and Group IV - WS treated SD group). Animals were deprived sleep for one week using a modified multiple platform method. Oxidative stress parameters and antioxidant enzymes were measured using spectrophotometry. Neurotransmitters such as dopamine and serotonin concentration in the serum were measured by ELISA method. There was a marked (by one-way ANOVA test) decrease observed in the antioxidants enzymes in the cortex of both large platform control and sleep deprivation induced group. The group treated with W. somnifera root extract significantly reduced the free radical production and lipid peroxidation with simultaneous increase in the level of antioxidant enzymes compared to the untreated group. Also in our study the concentration of dopamine and serotonin was found to be significantly reduced (p < 0.05) in sleep deprived (SD) and large platform control group when compared to cage control group. Whereas the group treated with W. somnifera (400mg/kg b.wt) increased the neurotransmitter levels significantly. Withania somnifera proved to be an effective therapeutic agent by maintaining the antioxidant status and neurotransmitter levels.

Coronavirus disease - COVID-19: new perceptives towards epidemic to pandemic.

The sudden outbreak and uncontrolled spread of the novel coronavirus disease 2019 (COVID-19) has shocked the world to a degree never seen before. Due to the wide spread transmission of the virus, the number of infected cases worldwide has surpassed 16,421,958 and global death toll has spiked up to 6,52,308 from December 2019 to 27 July 2020. The virus has been labelled as a pandemic by the WHO. Virologists have found that this virus outbreak is similar to past outbreaks of viruses such as severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East Respiratory Syndrome that caused severe respiratory syndrome and transmitted rapidly in humans. These single stranded RNA viruses come under the genera of ß-coronaviruses which ultimately infect lungs and respiratory tract. Even though the origin, source and intermediate hosts of this virus is unknown, transmittance from human-to-human through various paths has been identified globally. As of today, there are no approved drugs and vaccines. Several clinical trials are being conducted today to evaluate vaccines against the virus. The aim of our present review is to furnish brief details about the statistics, diagnosis, epidemiology, pathogenesis, prevention and treatment of COVID-19 to assist researchers and the society at large to come to grip with the deadly disease.HighlightsCumbersome outbreak of the novel Coronavirus Disease 2019 (COVID-19) became a pandemicAt June 19, 2020, as per WHO report 8,618,787 infected cases and 457,275 dead were recorded globallyMajor spread was found to be human to human transmissionsPeople with positive COVID-19 were infected with severe respiratory syndromeMore animal and clinical studies have to be done to overcome this pandemic.

CFD analysis on heat and flow characteristics of double helically coiled tube heat exchanger handling MWCNT/water nanofluids.

Double helically coiled tube heat exchangers are used in different heat transfer utilization due to higher heat transfer capabilities and with their compactness. The double helically coiled tube heat exchanger increases the turbulence and enhances the maximum heat transfer rate than the straight tubes. In this investigation, the heat transfer and pressure drop of the double helically coiled heat exchanger handling MWCNT/water nanofluids have been analyzed by the computational software ANSYS 14.5 version. The computational analysis was carried out under the laminar flow condition in the Dean number range of 1300-2200. The design of new shell and double helically coiled tube heat exchanger was done by using standard designing procedure and 3D modeling was done in Cre-O 2.0 parametric. The Finite Element Analysis software ANSYS Workbench 14.5 was used to perform CFD analysis under the standard working condition. The MWCNT/water nanofluids at 0.2%, 0.4%, and 0.6% volume concentrations have been taken for this investigation. The major factors like volume concentrations of nanofluids and Dean Number are considered for predicting the heat transfer rate and pressure drop. The simulation data was compared with the experimental data. It is studied that the heat transfer rate and pressure drop increase with increasing volume concentrations of MWCNT/water nanofluids. It is found that the Nusselt number of 0.6% MWCNT/water nanofluids is 30% higher than water at the Dean number value of 1400 and Pressure drop is 11% higher than water at the Dean number value of 2200. It is found that the simulation data hold good agreement with the experimental data. The common deviation between the Nusselt number and pressure dropof CFD data and the Nusselt number and pressure drop of experimental data are found to be 7.2% and 8.5% respectively.

In-silico design and synthesis of N9-substituted ß-Carbolines as PLK-1 inhibitors and their in-vitro/in-vivo tumor suppressing evaluation.

A new series of ß-Carboline/Schiff bases was designed, synthesized, characterised and biologically evaluated as inhibitors of PLK-1. The synthesized compounds exhibited strong to moderate cytotoxic activities against NCI-60 panel cell assay. Compound SB-2 was the most potent, particularly against colon with GI50 of 3-45 µM on NCI-60 panel cell lines. SB-2 selectively inhibited PLK-1 at 15 µM on KinomeScan screening. It also showed a dose-dependent cell cycle arrest at S/G2 phase on HCT-116 and induced apoptosis by the activation of procaspase-3 and cleaved PARP. Further, the antitumor studies on DLA and EAC model revealed that SB-2, at 100 mg/kg/bd.wt significantly increased their average lifespan. Further, a decrease in the body weight of the tumor-bearing mice was also observed when compared to the tumor controlled mice. SB-2 thus shows good potential as antitumor agent.

Thiazolidinediones as antidiabetic agents: A critical review.

Thiazolidinediones (TZDs) or Glitazones are an important class of insulin sensitizers used in the treatment of Type 2 diabetes mellitus (T2DM). TZDs were reported for their antidiabetic effect through antihyperglycemic, hypoglycemic and hypolipidemic agents. In time, these drugs were known to act by increasing the transactivation activity of Peroxisome Proliferators Activated Receptors (PPARs). The clinically used TZDs that suffered from several serious side effects and hence withdrawn/updated later, were full agonists of PPAR-γ and potent insulin sensitizers. These drugs were developed at a time when limited data were available on the structure and mechanism of PPARs. In recent years, however, PPAR-α/γ, PPAR-α/δ and PPAR-δ/γ dual agonists, PPAR pan agonists, selective PPAR-γ modulators and partial agonists have been investigated. In addition to these, several non PPAR protein alternatives of TZDs such as FFAR1 agonism, GPR40 agonism and ALR2, PTP1B and α-glucosidase inhibition have been investigated to address the problems associated with the TZDs. Using these rationalized approaches, several investigations have been carried out in recent years to develop newer TZDs devoid of side effects. This report critically reviews TZDs, their history, chemistry, mechanism mediated through PPAR, recent advances and future prospects.

The Blood Brain Barrier and its Role in Alzheimer's Therapy: An Overview.

BACKGROUND: Alzheimer's disease (AD) is the most frequent age related neurodegenerative disorder. It represents 70% of all dementia. Millions of people have been affected by AD worldwide. It is a complex illness characterized pathologically by accumulation of protein aggregates of amyloid and neurofibrillary tangles containing hyperphosphorylated neuronal tau protein. AD requires drugs that can circumvent the blood-brain barrier (BBB) which is not a simple physical barrier between blood and brain, but acts as an iron curtain, allowing only selective molecules to enter the brain. Unfortunately, this dynamic barrier restricts transport of drugs to the brain; due to which, currently very few drugs are available for AD treatment. OBJECTIVE: The present review focuses mainly on strategies used for administration of drug to the CNS by-passing BBB for the treatment of AD. RESULTS: Many studies have proved to be effective in overcoming BBB and targeting drugs to CNS by using different strategies. Here we have discussed some of the most important drug permeability and drug targeting approaches. CONCLUSION: In conclusion, concentrating solely in development of drug discovery programs is not enough but it is important to maintain balance between the drug discovery and drug delivery systems that are more specific and effective in targeting CNS of AD patients.

Novel HDAC8 inhibitors: A multi-computational approach.

Abnormal HDAC function triggers irregular gene transcription that hampers the essential cellular activities leading to tumour activation and progression. HDAC inhibition has, therefore, been reported as a potential target for cancer treatment. In the present study, a sequential computational framework was carried out to discover newer lead compounds, namely HDAC8 inhibitors for cancer therapy. Pharmacophoric hypotheses were generated based on hydroxamic acid derivatives reported earlier for HDAC inhibition. The model AAADR.122, demonstrated statistical significance (r2 = 0.93, Q2 = 0.81) and proved robust on validation with a cross-validated correlation coefficient of 0.89. It was utilized to arrive at novel hits through a virtual screening workflow. The specificity of the process was enhanced further by analysing the crucial interactions of the ligands with key catalytic residues, achieved by induced fit docking (PDB ID: 1T64). On assessment, the filtered leads displayed optimal drug like features. Investigations using density functional theory (DFT) also facilitated the recognition of molecular spots in the leads beneficial for HDAC8 interaction. Overall, two leads were proposed for HDAC8 inhibition with potential anti-cancer activity.

Few Atomic Layered Lithium Cathode Materials to Achieve Ultrahigh Rate Capability in Lithium-Ion Batteries.

The most promising cathode materials, including LiCoO2 (layered), LiMn2 O4 (spinel), and LiFePO4 (olivine), have been the focus of intense research to develop rechargeable lithium-ion batteries (LIBs) for portable electronic devices. Sluggish lithium diffusion, however, and unsatisfactory long-term cycling performance still limit the development of present LIBs for several applications, such as plug-in/hybrid electric vehicles. Motivated by the success of graphene and novel 2D materials with unique physical and chemical properties, herein, a simple shear-assisted mechanical exfoliation method to synthesize few-layered nanosheets of LiCoO2 , LiMn2 O4 , and LiFePO4 is used. Importantly, these as-prepared nanosheets with preferred orientations and optimized stable structures exhibit excellent C-rate capability and long-term cycling performance with much reduced volume expansion during cycling. In particular, the zero-strain insertion phenomenon could be achieved in 2-3 such layers of LiCoO2 electrode materials, which could open up a new way to the further development of next-generation long-life and high-rate batteries.

Consensus statement on anaesthesia for day care surgeries.

The primary aim of day-care surgery units is to allow for early recovery of the patients so that they can return to their familiar 'home' environment; the management hence should be focused towards achieving these ends. The benefits could include a possible reduction in the risk of thromboembolism and hospital-acquired infections. Furthermore, day-care surgery is believed to reduce the average unit cost of treatment by up to 70% as compared to inpatient surgery. With more than 20% of the world's disease burden, India only has 6% of the world's hospital beds. Hence, there is an immense opportunity for expansion in day-care surgery in India to ensure faster and safer, cost-effective patient turnover. For this to happen, there is a need of change in the mindset of all concerned clinicians, surgeons, anaesthesiologists and even the patients. A group of nine senior consultants from various parts of India, a mix of private and government anaesthesiologists, assembled in Mumbai and deliberated and discussed on the various aspects of day-care surgery. They formulated a consensus statement, the first of its kind in the Indian scenario, which can act as a guidance and tool for day-care anaesthesia in India. The statements are derived from the available published evidence in peer-reviewed literature including guidelines of several bodies such as the American Society of Anesthesiologists, British Association of Day Surgery and International Association of Ambulatory Surgery. The authors also offer interpretive comments wherever such evidence is inadequate or contradictory.

Poly(malic acid) bearing Doxorubicin and N-Acetyl Galactosamine as a site-specific prodrug for targeting hepatocellular carcinoma.

In the past, several systems of drug delivery carriers have been designed with a high capacity to target specific cells and/or tissues and a reduced non-specific toxicity. In this context, we synthesized and characterized novel poly(malic acid) derivatives bearing Doxorubicin (Dox), Poly(ethylene glycol) (PEG) and/or N-Acetyl Galactosamine (NAcGal) for drug delivery. These poly(malic acid) derivatives were obtained by chemical modification of the carboxylic acid lateral groups of poly(malic acid) (PMLA). The resulting nanoplatforms were evaluated for their in vitro cytotoxicity using the human HepaRG hepatoma cell line. Results reveal that the PMLA nanoplatform modified with PEG and Dox has an IC50 of 936 nM corresponding to a Dox concentration of 47 nM, while the grafting of NAcGal onto the nanoplatform reduced the IC50 to 527 nM corresponding to a Dox concentration of 26 nM. The presence of the targeting moiety, NAcGal, thus improves the cellular toxicity of the Dox.

Inhibitors of histone deacetylase as antitumor agents: A critical review.

Histone deacetylase (EC 3.5.1.98 - HDAC) is an amidohydrolase involved in deacetylating the histone lysine residues for chromatin remodeling and thus plays a vital role in the epigenetic regulation of gene expression. Due to its aberrant activity and over expression in several forms of cancer, HDAC is considered as a potential anticancer drug target. HDAC inhibitors alter the acetylation status of histone and non-histone proteins to regulate various cellular events such as cell survival, differentiation and apoptosis in tumor cells and thus exhibit anticancer activity. Till date, four drugs, namely Vorinostat (SAHA), Romidepsin (FK-228), Belinostat (PXD-101) and Panobinostat (LBH-589) have been granted FDA approval for cancer and several HDAC inhibitors are currently in various phases of clinical trials, either as monotherapy and/or in combination with existing/novel anticancer agents. Regardless of this, today scientific efforts have fortified the quest for newer and novel HDAC inhibitors that show isoform selectivity. This review focuses on the chemistry of the molecules of two classes of HDAC inhibitors, namely short chain fatty acids and hydroxamic acids, investigated so far as novel therapeutic agents for cancer.