Assessment of In Vitro and In Vivo Bioremediation Potentials of Orally Supplemented Free and Microencapsulated Lactobacillus acidophilus KLDS Strains to Mitigate the Chronic Lead Toxicity

Lead (Pb) is a pestilent and relatively nonbiodegradable heavy metal, which causes severe health effects by inducing inflammation and oxidative stress in animal and human tissues. This is because of its significant tolerance and capability to bind Pb (430 mg/L) and thermodynamic fitness to sequester Pb in the Freundlich model (R2 = 0.98421) in vitro. Lactobacillus acidophilus KLDS1.1003 was selected for further in vivo study both in free and maize resistant starch (MRS)–based microencapsulated forms to assess its bioremediation aptitude against chronic Pb lethality using adult female BALB/c mice as a model animal. Orally administered free and microencapsulated KLDS 1.1003 provided significant protection by reducing Pb levels in the blood (127.92 ± 5.220 and 101.47 ± 4.142 µg/L), kidneys (19.86 ± 0.810 and 18.02 ± 0.735 µg/g), and liver (7.27 ± 0.296 and 6.42 ± 0.262 µg/g). MRS-microencapsulated KLDS 1.0344 improved the antioxidant index and inhibited changes in blood and serum enzyme concentrations and relieved the Pb-induced renal and hepatic pathological damages. SEM and EDS microscopy showed that the Pb covered the surfaces of cells and was chiefly bound due to the involvement of the carbon and oxygen elements. Similarly, FTIR showed that the amino, amide, phosphoryl, carboxyl, and hydroxyl functional groups of bacteria and MRS were mainly involved in Pb biosorption. Based on these findings, free and microencapsulated L. acidophilus KLDS 1.0344 could be considered a potential dietetic stratagem in alleviating chronic Pb toxicity.

Design of proteasome inhibitors with oral efficacy in vivo against Plasmodium falciparum and selectivity over the human proteasome

The Plasmodium falciparum proteasome is a potential antimalarial drug target. We have identified a series of amino-amide boronates that are potent and specific inhibitors of the P. falciparum 20S proteasome (Pf20S) β5 active site and that exhibit fast-acting antimalarial activity. They selectively inhibit the growth of P. falciparum compared with a human cell line and exhibit high potency against field isolates of P. falciparum and Plasmodium vivax. They have a low propensity for development of resistance and possess liver stage and transmission-blocking activity. Exemplar compounds, MPI-5 and MPI-13, show potent activity against P. falciparum infections in a SCID mouse model with an oral dosing regimen that is well tolerated. We show that MPI-5 binds more strongly to Pf20S than to human constitutive 20S (Hs20Sc). Comparison of the cryo-electron microscopy (EM) structures of Pf20S and Hs20Sc in complex with MPI-5 and Pf20S in complex with the clinically used anti-cancer agent, bortezomib, reveal differences in binding modes that help to explain the selectivity. Together, this work provides insights into the 20S proteasome in P. falciparum, underpinning the design of potent and selective antimalarial proteasome inhibitors.

Comparison of in vitro and in vivo Toxicity of Bupivacaine in Musculoskeletal Applications

The recent societal debate on opioid use in treating postoperative pain has sparked the development of long-acting, opioid-free analgesic alternatives, often using the amino-amide local anesthetic bupivacaine as active pharmaceutical ingredient. A potential application is musculoskeletal surgeries, as these interventions rank amongst the most painful overall. Current literature showed that bupivacaine induced dose-dependent myo-, chondro-, and neurotoxicity, as well as delayed osteogenesis and disturbed wound healing in vitro. These observations did not translate to animal and clinical research, where toxic phenomena were seldom reported. An exception was bupivacaine-induced chondrotoxicity, which can mainly occur during continuous joint infusion. To decrease opioid consumption and provide sustained pain relief following musculoskeletal surgery, new strategies incorporating high concentrations of bupivacaine in drug delivery carriers are currently being developed. Local toxicity of these high concentrations is an area of further research. This review appraises relevant in vitro, animal and clinical studies on musculoskeletal local toxicity of bupivacaine.

Facile Synthesis of L-Cysteine Functionalized Graphene Quantum Dots as a Bioimaging and Photosensitive Agent

Nowadays, a larger number of aggressive and corrosive chemical reagents as well as toxic solvents are used to achieve structural modification and cleaning of the final products. These lead to the production of residual, waste chemicals, which are often reactive, cancerogenic, and toxic to the environment. This study shows a new approach to the modification of graphene quantum dots (GQDs) using gamma irradiation where the usage of reagents was avoided. We achieved the incorporation of S and N atoms in the GQD structure by selecting an aqueous solution of L-cysteine as an irradiation medium. GQDs were exposed to gamma-irradiation at doses of 25, 50 and 200 kGy. After irradiation, the optical, structural, and morphological properties, as well as the possibility of their use as an agent in bioimaging and photodynamic therapy, were studied. We measured an enhanced quantum yield of photoluminescence with the highest dose of 25 kGy (21.60%). Both S- and N-functional groups were detected in all gamma-irradiated GQDs: amino, amide, thiol, and thione. Spin trap electron paramagnetic resonance showed that GQDs irradiated with 25 kGy can generate singlet oxygen upon illumination. Bioimaging on HeLa cells showed the best visibility for cells treated with GQDs irradiated with 25 kGy, while cytotoxicity was not detected after treatment of HeLa cells with gamma-irradiated GQDs.

Biologically Active α-Amino Amide Analogs and γδ T Cells—A Unique Anticancer Approach for Leukemia

Advanced stage cancers are aggressive and difficult to treat with mono-therapeutics, substantially decreasing patient survival rates. Hence, there is an urgent need to develop unique therapeutic approaches to treat cancer with superior potency and efficacy. This study investigates a new approach to develop a potent combinational therapy to treat advanced stage leukemia. Biologically active α-amino amide analogs (RS)-N-(2-(cyclohexylamino)-2-oxo-1-phenylethyl)-N-phenylpropiolamide (α-AAA-A) and (RS)-N-(2-(cyclohexylamino)-2-oxo-1-phenylethyl)-N-phenylbut2-enamide (α-AAA-B) were synthesized using linear Ugi multicomponent reaction. Cytotoxicities and IC50 values of α-AAA-A and α-AAA-B against leukemia cancer cell lines (HL-60 and K562) were analyzed though MTT assay. Cytotoxic assay analyzed percent killing of leukemia cell lines due to the effect of γδ T cells alone or in combination with α-AAA-A or α-AAA-B. Synthesized biologically active molecule α-AAA-A exhibited increased cytotoxicity of HL-60 (54%) and K562 (44%) compared with α-AAA-B (44% and 36% respectively). Similarly, α-AAA-A showed low IC50 values for HL-60 (1.61 ± 0.11 μM) and K562 (3.01 ± 0.14 μM) compared to α-AAA-B (3.12 ± 0.15 μM and 6.21 ± 0.17 μM respectively). Additive effect of amide analogs and γδ T cells showed significantly high leukemia cancer cell killing as compared to γδ T cells alone. A unique combinational therapy with γδ T cells and biologically active anti-cancer molecules (α-AAA-A/B), concomitantly may be a promising cancer therapy.

Influence of N-Methylation and Conformation on Almiramide Anti-Leishmanial Activity

The almiramide N-methylated lipopeptides exhibit promising activity against trypanosomatid parasites. A structure–activity relationship study has been performed to examine the influences of N-methylation and conformation on activity against various strains of leishmaniasis protozoan and on cytotoxicity. The synthesis and biological analysis of twenty-five analogs demonstrated that derivatives with a single methyl group on either the first or fifth residue amide nitrogen exhibited greater activity than the permethylated peptides and relatively high potency against resistant strains. Replacement of amino amide residues in the peptide, by turn inducing α‑amino γ‑lactam (Agl) and N-aminoimidazalone (Nai) counterparts, reduced typically anti-parasitic activity; however, peptide amides possessing Agl residues at the second residue retained significant potency in the unmethylated and permethylated series. Systematic study of the effects of methylation and turn geometry on anti-parasitic activity indicated the relevance of an extended conformer about the central residues, and conformational mobility by tertiary amide isomerization and turn geometry at the extremities of the active peptides.

Utilization of Intravenous Lidocaine Infusion for the Treatment of Refractory Chronic Pain

Context: Chronic pain accounts for one of the most common reasons patients seek medical care. The financial burden of chronic pain on health care is seen by direct financial cost and resource utilization. Many risk factors may contribute to chronic pain, but there is no definite risk. Managing chronic pain is a balance between maximally alleviating symptoms by utilizing a therapeutic regimen that is safe for long-term use. Currently, non-opioid analgesics, NSAIDs, and opioids are some of the medical treatment options, but these have numerous adverse effects and may not be the best option for long-term use. However, Lidocaine can achieve both central and peripheral analgesic effects with relatively few side effects, which may be an ideal compound for managing chronic pain. Evidence Acquisition: This is a Narrative Review. Results: Infusion of lidocaine (2-(diethylamino)-N-(2,6-dimethylphenyl)acetamide), an amino-amide compound, is emerging as a promising option to fill the therapeutic void for treatment of chronic pain. Numerous studies have outlined dosing protocols for lidocaine infusion for the management of perioperative pain, outlined below. While there are slight variations in these different protocols, they all center around a similar dosing regimen to administer a bolus to reach a rapid steady state, followed by infusion for up to 72 hours to maintain the therapeutic analgesic effects. Conclusions: Lidocaine may be a promising pharmacologic solution with a low side effect profile that provides central and peripheral analgesia. Even though the multifaceted mechanism is not entirely understood yet, lidocaine may be a promising novel remedy in treating chronic pain in various conditions.

Chemical Tools for Study of Phosphohistidine: Generation of Selective τ-Phosphohistidine and π-Phosphohistidine Antibodies

Non-hydrolysable stable analogues of τ-pHis and π-pHis have been designed using electrostatic surface potential calculations, and subsequently synthesized. The τ-pHis and π-pHis analogues (phosphopyrazole <b>8 </b>and pyridyl amino amide <b>13</b>, respectively)<b> </b>were used as haptens to generate pHis polyclonal antibodies. <a>Both τ-pHis and π-pHis conjugates in the form of a BSA-glutaraldehyde-τ-pHis and BSA-glutaraldehyde-π-pHis</a> were synthesized and characterized by ³¹P NMR spectroscopy. Commercially available τ-pHis (SC56-2) and π-pHis (SC1-1; SC50-3) monoclonal antibodies were used to show that the BSA-G-τ-pHis and BSA-G-π-pHis conjugates could be used to assess the selectivity of pHis antibodies in a competitive ELISA. Subsequently, the selectivity of the generated pHis antibodies generated using phosphopyrazole <b>8 </b>and pyridyl amino amide <b>13</b> as haptens was assessed by competitive ELISA against His, pSer, pThr, pTyr, τ-pHis and π-pHis. Antibodies generated using the phosphopyrazole <b>8</b> as a hapten were found to be selective for τ-pHis, and antibodies generated using the <a>pyridyl amino amide <b>13</b> </a>were found to be selective for π-pHis. Both τ- and π-pHis antibodies were shown to be effective in immunological experiments, including ELISA, western blot, and immunofluorescence. The τ-pHis antibody was also shown to be useful in the immunoprecipitation of proteins containing pHis

Chemical Tools for Study of Phosphohistidine: Generation of Selective τ-Phosphohistidine and π-Phosphohistidine Antibodies

Non-hydrolysable stable analogues of τ-pHis and π-pHis have been designed using electrostatic surface potential calculations, and subsequently synthesized. The τ-pHis and π-pHis analogues (phosphopyrazole <b>8 </b>and pyridyl amino amide <b>13</b>, respectively)<b> </b>were used as haptens to generate pHis polyclonal antibodies. <a>Both τ-pHis and π-pHis conjugates in the form of a BSA-glutaraldehyde-τ-pHis and BSA-glutaraldehyde-π-pHis</a> were synthesized and characterized by ³¹P NMR spectroscopy. Commercially available τ-pHis (SC56-2) and π-pHis (SC1-1; SC50-3) monoclonal antibodies were used to show that the BSA-G-τ-pHis and BSA-G-π-pHis conjugates could be used to assess the selectivity of pHis antibodies in a competitive ELISA. Subsequently, the selectivity of the generated pHis antibodies generated using phosphopyrazole <b>8 </b>and pyridyl amino amide <b>13</b> as haptens was assessed by competitive ELISA against His, pSer, pThr, pTyr, τ-pHis and π-pHis. Antibodies generated using the phosphopyrazole <b>8</b> as a hapten were found to be selective for τ-pHis, and antibodies generated using the <a>pyridyl amino amide <b>13</b> </a>were found to be selective for π-pHis. Both τ- and π-pHis antibodies were shown to be effective in immunological experiments, including ELISA, western blot, and immunofluorescence. The τ-pHis antibody was also shown to be useful in the immunoprecipitation of proteins containing pHis