Thiophosphorylation of histidine

The preparation of a novel phosphorus species, thiophosphoramidate, has enabled the specific thiophosphorylation of histidine at its 3-position. The rates of phosphorylation and thiophosphorylation of histidine are reported, as well as the spectroscopic properties of both thiophosphoramidate and 3-thiophosphohistidine. Structural assignment of the latter was made by analogy to the NMR properties of the known 3-phosphohistidine. The alkylation of 3-thiophosphohistidine by phenacyl bromide serves as a model for the introduction of labeling or probe reagents into histidine phosphorothioate-containing proteins.

Recognition of 5-aminouracil (U(#)) in the central strand of a DNA triplex: orientation selective binding of different third strand bases

A necessary feature of the natural base triads for triplex formation is the requirement of a purine (A or G) in the central position, since only these provide sets of two hydrogen bond donors/acceptors in the major groove of the double helix. Pyrimidine bases devoid of this feature have incompatible complementarity and lead to triplexes with lower stability. This paper demonstrates that 5-aminouracil (U#) (I), a pyrimidine nucleobase analogue of T in which 5-methyl is replaced by 5-amino group, with hydrogen bonding sites on both sides, is compatible in the central position of triplex triad X*U# x A, where X = A/G/C/T/2-aminopurine (AP), and * and x represent Hoogsteen and Watson-Crick hydrogen bonding patterns respectively. A novel recognition selectivity based on the orientation (parallel/antiparallel) of the third strand purines A, G or AP with A in the parallel motif (A(p)*U# x A), and G/AP in the antiparallel motif (G(ap)/AP(ap)*U# x A) is observed. Similarly for pyrimidines in the third strand, C is accepted only in a parallel mode (C(p)*U(#) x A). Significantly, T is recognised in both parallel and antiparallel modes (T(p)/T(ap)*U(#) x A), with the antiparallel mode being stable compared to the parallel one. The 'U(#)' triplexes are also more stable than the corresponding control 'T' triplexes. The results expand the lexicon of triplex triads with a recognition motif consisting of pyrimidine in the central strand.

Revisiting liquorice (Glycyrrhiza glabra L.) as anti-inflammatory, antivirals and immunomodulators: Potential pharmacological applications with mechanistic insight

BACKGROUND

Glycyrrhiza glabra L. (G. glabra) commonly known as liquorice is one of the highly exploited and utilized medicinal plant of the world. Since ancient times liquorice is considered as an auspicious and valuable traditional medicine across the world for treatment of various ailments.

METHOD

Several electronic online scientific databases such as Science Direct, PubMed, Scopus, Scifinder, Google Scholar, online books and reports were assessed for collecting information. All the collected information was classified into different sections to meet the objective of the paper.

RESULTS

The electronic database search yielded 3908 articles from different countries. Out of them one ninety-eight articles published between 1956 and 2021 were included, corresponding to all detailed review on G. glabra and research on anti-inflammatories, antivirals and immunomodulatory through pre-clinical and clinical models. From all selective area of studies on G. glabra and its bioactive components it was established (including molecular mechanisms) as a suitable remedy as per the current requirement of pandemic situation arise through respiratory tract infection.

CONCLUSION

Different relevant studies have been thoroughly reviewed to gain an insight on utility of liquorice and its bioactive constituents for anti-inflammatories, antivirals and immunomodulatory effects with special emphasized for prevention and treatment of COVID-19 infection with possible mechanism of action at molecular level. Proposed directions for future research are also outlined to encourage researchers to find out various mechanistic targets and useful value added products of liquorice in future investigations.

5-Amino-dU: a nucleoside analogue in the central strand of DNA triplex for orientation selective binding of A/G/C/T in the third strand

[formula: see text] 5-Amino-dU, a designed nucleoside analogue, when placed in the central strand of DNA triple helix, recognizes all four bases A, G, C, and T in the third strand, with a selectivity based on the orientation (parallel/antiparallel) of the third strand.

An overview on therapeutic and medicinal potential of poly-hydroxy flavone viz. Heptamethoxyflavone, Kaempferitrin, Vitexin and Amentoflavone for management of Alzheimer's and Parkinson's diseases: a critical analysis on mechanistic insight

Neurodegenerative disorders occur when nerve cells in the brain or peripheral nervous system partial or complete fail in their functions and sometimes even die due to some injuries or aging. Neurodegenerative disorders such as Alzheimer's Disease (AD) and Parkinson's Disease (PD), have been majorly resulted due to degeneration of neurons and neuroinflammation progressively. There are many similarities that correlates both AD and PD on a cellular and sub-cellular level. Therefore, a hope for therapeutic advancement for simultaneous upgradation in both the diseases are directly depending on the discovery of common mechanism at molecular and cellular level. Recent and past evidences from scientific literature supporting the efficacy of plants flavonoids in treatment and protection of both AD and PD. Further, dietary flavones, specially Heptamethoxyflavone, Kaempferitrin, Vitexin and Amentoflavone gains recently much more attention for producing many health beneficiary effects including neuroprotection. Despite of these evidence a detailed updated overview of neuroprotective effects against both AD and PD by Heptamethoxyflavone, Kaempferitrin, Vitexin and Amentoflavone are still missing. In this context several published studies were assessed by using various online electronic search engines/databases to meet the objective from 1981 to 2021 (Approx. 224). Therefore, present review was designed to deliver the detailed description on these flavones including therapeutic benefits in AD, PD and other CNS complications with critical analysis on underlying mechanisms.

Massive lower intestinal bleeding--a decade of experience

BACKGROUND

Lower gastrointestinal bleeding is defined as hemorrhage orginating distal to the ligament of Treitz. Its diagnosis is difficult, often requiring endoscopy, angiography and isotope scans.

METHODS

All patients with massive lower gastrointestinal bleeding seen in three gastroenterology centers of Armed Forces during an 11 year period between 1988 and 1999 were retrospectively analysed.

RESULTS

A total of 91 patients with massive lower gastro intestinal bleeding were seen during 11 years. The mean age of the patients was 38.9 years and 64 were males. Aetiological diagnosis was: Non-specific ulcers--11, Ileal tuberculosis--8, NSAID enteropathy--8, Enteric fever--7, Meckel's diverticulum--7, Polyps--6, Ulcerative colitis--5, Carcinoma colon--5, Colonic diverticulosis--5, No cause found--5, Polyposis coli--5, Jejunal diverticulae--3, Angiodysplasia colon--3, Radiation colitis--3, Ischaemic colitis--3, Ileal tumor--2, Ileal angiodysplasia--2, Intestinal Lymphoma--2, Bechet's syndrome--1. Bleeding stopped on conservative therapy in 18 patients (including 5 where no diagnosis could be made). Diagnosis was made in 36 patients on fiber-optic colonoscopy done during active bleeding. Remaining patients were subjected to emergency laparotomy and diagnosis was obvious on inspection of abdominal contents in 25 cases. The diagnosis was finally made in remaining 12 cases by intraoperative endoscopic examination through an ileotomy. Four patients died, only one of them due to rebleed after surgery from an additional lesion.

CONCLUSIONS

Compared with experience in Western countries, massive lower gastro-intestinal hemorrhage in India affects younger patients, has different causes and carries a lower mortality. Colonoscopy is useful in making diagnosis during active lower intestinal bleeding in about one-third cases. Exploratory laparotomy and Intra-operative endoscopy are complimentary to above examination and can make the diagnosis in most of the remaining cases.

Synthesis and Characterization of Baicalein-loaded Aquasomes: An In vitro and In silico Perspective for Diabetes Mellitus

BACKGROUND

Millions of individuals worldwide suffer from metabolic abnormalities induced by diabetes. Baicalein, a flavonoid, has shown several properties in various treatments with potential properties, including anti-inflammatory, antioxidant, and anti-diabetic properties. Practically, its application is hindered due to low solubility in aqueous media. Overcoming this challenge, aquasomes can offer an effective approach for delivering drugs and bioactive molecules to target various diseases.

OBJECTIVE

The study aimed to develop and evaluate baicalein-loaded aquasomes for improving solubility and comparing their antidiabetic properties to acarbose through in silico docking.

METHODS

Baicalein-loaded aquasomes were prepared through a three-step process: core preparation, lactose coating, and drug loading. The evaluation included assessing particle size, drug-excipient interactions, drug entrapment efficiency, loading capacity, in vitro drug release, and the kinetics of drug release. In silico docking and in vitro α-amylase inhibition activity was evaluated to assess the anti-diabetic potential of baicalein.

RESULTS

The baicalein-loaded aquasomes were spherical with sizes ranging from 300-400 nm. FTIR analysis indicated no interaction between the components. The formulation exhibited drug entrapment efficiency of 94.04±0 4.01% and drug loading of 17.60 ± 01.03%. Drug release study showed sustained and complete (97.30 ± 02.06%) release, following first-order kinetics. Docking analysis revealed comparable binding affinity to acarbose, while the α-amylase inhibition assay showed greater inhibition potential of the aquasomes compared to the baicalein solution.

CONCLUSION

Aquasomes offer an alternative approach to conventional delivery methods. The selfassembling characteristics of aquasomes greatly simplify their preparation process, adding to their appeal as a drug delivery system.

Massive lower gastrointestinal bleeding as a presenting feature of Behcet's disease

This reports a 27 yr old female Patient with seronegative polyarthritis who presented with lower GI bleeding and subsequently developed evidence of cutaneous vasculitis (palpable purpura) and orogenital ulcers. The cause of the GI bleeding was multiple ulcerations in the terminal ileum, cecum ascending colon and transverse colon. Continued and massive bleeding necessitated surgical resection of the involved segment of gut which on histopathological examination confirmed the presence of vasculities. This patient was thus diagnosed as having Behcet's disease. Although major GI bleeding is a rare manifestation of Behcet's disease with vasculitis of the gut, one must consider this possibility if the patient has multi-system involvement with evidence of vasculitis involving the skin in the form of palpable purpura.

A Validated High-Performance Thin-Layer Chromatography Technique for Routine Analysis of Curcumin in Four Different Species of Curcuma Viz. C. amada, C. caesia, C. longa and C. zedoaria

In this study, we investigated a new, simple, sensitive, selective and precise high-performance thin-layer chromatography (HPTLC) fingerprint and quantitative estimation method for the routine analysis of curcumin in Curcuma species viz. Curcuma amada, Curcuma caesia, Curcuma longa and Curcuma zedoaria. Linear ascending development was carried out in a twin-trough glass chamber saturated with toluene:acetic acid (4:1; v/v with 20 minutes of saturation). The plate was dried and analyzed by CAMAG TLC scanner III at white light and 366 nm. The system was found to give compact spots for curcumin (Rf 0.42). The relationship between the concentration of standard solutions and the peak response is linear within the concentration range of 10-70 ng/spot for curcumin. In result, curcumin was not detected in any of C. caesia extracts. The percentage of curcumin was found between 0.042 and 4.908 (%w/w) in different Curcuma species obtained by two different extraction methods viz. Soxhlet and sonication, respectively. Further, extraction via Soxhlet method is most suitable method to get higher curcumin content from rhizomes. The proposed HPTLC method may be use for routine quality testing and quantification of curcumin in Curcuma samples.

Boosting the Biocontrol Efficacy of Bacillus amyloliquefaciens DSBA-11 through Physical and Chemical Mutagens to Control Bacterial Wilt Disease of Tomato Caused by Ralstonia solanacearum

Bacterial wilt disease of tomato (Solanum lycopersicum L.), incited by Ralstonia solanacearum (Smith), is a serious agricultural problem in India. In this investigation, chemical mutagenic agents (NTG and HNO₂ treatment) and ultraviolet (UV) irradiation have been used to enhance the antagonistic property of Bacillus amyloliquefaciens DSBA-11 against R. solanacearum UTT-25 towards an effective management of tomato wilt disease. The investigation established the fact that maximum inhibition to R. solanacearum UTT-25 was exerted by the derivative strain MHNO₂-20 treated with nitrous acid (HNO₂) and then by the derivative strain MNTG-21 treated with NTG. The exertion was significantly higher than that of the parent B. amyloliquefaciens DSBA-11. These two potential derivatives viz. MNTG-21, MHNO₂-20 along with MUV-19, and a wild derivative strain of B. amyloliquefaciens i.e.,DSBA-11 were selected for GC/MS analysis. Through this analysis 18 major compounds were detected. Among the compounds thus detected, the compound 3-isobutyl hexahydropyrrolo (1,2), pyrazine-1,4-dione (4.67%) was at maximum proportion in the variant MHNO₂-20 at higher retention time (RT) of 43.19 s. Bio-efficacy assessment observed a record of minimum intensity (9.28%) in wilt disease and the highest bio-control (88.75%) in derivative strain MHNO₂-20-treated plants after 30 days of inoculation. The derivative strain MHNO₂-20, developed by treating B. amyloliquefaciens with nitrous acid (HNO₂), was therefore found to have a higher bio-efficacy to control bacterial wilt disease of tomato under glasshouse conditions than a wild-type strain.