Effect of Aegle marmelos on the growth of brushite crystals

Background

The urinary stone formation is a very common health problem due to the prolonged medication. Calcium Hydrogen Phosphate Dihydrate (CaHPO4.2H2O, CHPD and Brushite) is one of the major constituent of urinary stone crystals. The formation and deposition of brushite crystals is the central cause of recurrent kidney stone disease among the global population. The present study aims to investigate the effect of Aegle marmelos leaves on the growth of brushite crystals to explicate the inhibitory effect of urinary stones from a different point of view.

Methods

The CHPD crystals were grown by the Single Diffusion Gel growth technique. In order to inhibit the formation of urinary stones, CHPD crystals are grown in the laboratory in the pure form and by adding the prolonged medicine A. marmelos taken especially by diabetic patients. A comparative study of the pure and A. marmelos leaves added crystals has been carried out using the Growth factor, Powder X-ray diffraction, Microstructural parameters, FTIR and SEM-EDAX.

Results

Total mass of the grown crystals is found to decrease with increasing concentrations of leaf extract of the A. marmelos. On comparing with undoped, crystalline size of the A. marmelos doped samples is reduced. Disappearance of absorption band and peak shift in the FTIR shows the incorporation of functional groups of A. marmelos. The morphology changes of the treated crystals are assessed in SEM.

Conclusions

The result shows that herbal extracts prepared from A. marmelos have good inhibitory effect on the growth of the brushite urinary stone crystals considered.

Electrospray ionization tandem mass spectrometric study of protonated and alkali- cationized α/ε-hybrid peptides: differentiation of a pair of dipeptide positional isomers

A new class of Boc-N-protected hybrid peptides derived from L- Ala and ε⁶-Caa (L-Ala = L-Alanine, Caa = C-linked carboamino acid derived from D-xylose) have been studied by positive ion electrospray ionization (ESI) ion-trap tandem mass spectrometry (MS/MS). MSⁿ spectra of protonated and alkali-cationized hybrid peptides produce characteristic fragmentation involving the peptide backbone, the tert-butyloxycarbonyl (Boc) group, and the side chain. The dipeptide positional isomers are differentiated by the collision-induced dissociation (CID) of the protonated and alkali-cationized peptides. The CID of [M + H]⁺ ion of Boc-NH-L-Ala-ε-Caa- OCH₃ (1) shows a prominent [M + H - C₄H₈]⁺ ion, which is totally absent for its positional isomer Boc-NH-ε-Caa-L-Ala-OCH₃ (6), which instead shows significant loss of t-butanol. The formation of the [M + Cat - C₄H₈]⁺ ion is totally absent and [M + Cat - Boc + H]⁺ is prominent in the CID of the [M + Cat]⁺ ion of Boc-NH-L-Ala-ε-Caa- OCH₃ (1), whereas the former is highly abundant and the latter is of low abundance for its positional isomer Boc-NH-ε-Caa-L-Ala-OCH₃ (6). It is observed that 'b' ions are abundant when oxazolone structures are formed through a five-membered cyclic transition state in tetra-, penta-, and hexapeptides and the cyclization process for larger 'b' ions led to an insignificant abundance. However, the significant 'b' ion is formed in ε,α-dipeptide, which may have a seven-membered substituted 2-oxoazepanium ion structure. The MSⁿ spectra of [M + Cat - Boc + H]⁺ ions of these peptides are found to be significantly different to those of [M + H - Boc + H]⁺ ions. The CID spectra of [M + Cat - Boc + H]⁺ ions of peptide acids containing L-Ala at the C-terminus show an abundant N-terminal rearrangement ion, [bⁿ + 17 + Cat]⁺, which is absent for the peptide acids containing ε-Caa at the C-terminus. Thus, the results of these hybrid peptides provide sequencing information, the structure of the cyclic intermediate involved in the formation of the rearrangement ion, and distinguish a pair of dipeptide positional isomers.

Odontogenic Keratocyst of Coronoid process presenting as an infratemporal mass

A pediatric patient presented with facial swelling. CT scans showed a left infratemporal mass with erosion of coronoid process and normal dentition. CT guided FNAB suggested the possibility of odontogenic keratocyst. The mass was excised by a transzygomatic approach. A four year followup has not shown any recurrence. The possibility of odontogenic keratocyst needs to be considered while evaluating infratemporal fossa swellings. DOI: http://dx.doi.org/10.3329/bjo.v20i2.22028 Bangladesh J Otorhinolaryngol; October 2014; 20(2): 106-108

Studies on non-covalent interaction of coumarin attached pyrimidine and 1-methyl indole 1,2,3 triazole analogues with intermolecular telomeric G-quadruplex DNA using ESI-MS and spectroscopy

In the present study, electrospray ionization mass spectrometry (ESI-MS) and spectroscopy have been used to evaluate the non-covalent interaction, stoichiometry, and selectivity of two synthetic coumarin-attached nucleoside and non-nucleoside 1,2,3-triazoles, namely, (1-(5-(hydroxymethyl)-4-(4-((2-oxo-2H-chromen-4-yloxy)methyl)-1H-1,2,3-triazol-1-yl)tetrahydro-furan-2-yl)5-methyl pyrimidine-2,4(1H,3H)-dione (Tr1) and 4-((1-((-1-methyl-1H-indol-2-yl)methyl)-1H-1,2,3-triazol-4-yl)methoxy)-2H-chromen-2-one (Tr2) with two different human telomeric intermolecular G-quadruplex DNA structures formed by d(T2AG3) and d(T2AG3)2 sequences. ESI-MS studies indicate that Tr1 specifically interacts with four-stranded intermolecular parallel quadruplex complex, whereas Tr2 interacts with two hairpin as well as four-stranded intermolecular parallel quadruplex complexes. UV-Visible spectroscopic studies suggest that Tr1 and Tr2 interact with G-quadruplex structure and unwind them. Job plots show that stoichiometry of ligand:quadruplex DNA is 1:1. Circular dichroism (CD) studies of G-quadruplex DNA and Tr1/Tr2 ligands manifest that they unfold DNA on interaction. Fluorescence studies demonstrate that ligand molecules intercalate between the two stacks of quadruplex DNA and non-radiative energy transfer occurs between the excited ligand molecules (donor) and quadruplex DNA (acceptor), resulting in enhancement of fluorescence emission intensity. Thus, these studies suggest that nucleoside and non-nucleoside ligands efficiently interact with d(T2AG3) and d(T2AG3)2 G-quadruplex DNA but the interaction is not alike with all kinds of quadruplex DNA, this is probably due to the variation in the pharmacophores and structure of the ligand molecules.

Liquid chromatography electrospray ionization tandem mass spectrometry study of nilutamide and its stress degradation products: in silico toxicity prediction of degradation products

Nilutamide, a nonsteroidal anti-androgen drug, widely used in the treatment of prostate cancer, was subjected to hydrolytic, photolytic, thermal and oxidative stress conditions as per International Conference on Harmonization guidelines Q1A (R2). Nilutamide showed significant degradation under basic hydrolysis and photolytic stress conditions, while it was stable to neutral, acidic and thermal stress conditions. Five degradation products were formed and the chromatographic separation of nilutamide and its degradation products was achieved on a Waters C18 column (4.6 × 250 mm, 5 µm) using a mobile phase consisting of acetonitrile and 0.1% of formic acid in an isocratic elution method. All these degradation products were characterized by LC/MS/MS in negative ion mode, combined with accurate mass measurements. To assign likely structures for the observed degradation products, the fragmentation patterns of the deprotonated drug and its degradation products were compared. The in silico toxicity of the drug and its degradation products was also assessed using TOPKAT software. The carcinogenicity probability of the degradation products, DP-I-IV, was greater than that of nilutamide.

Electrospray ionization tandem mass spectrometry of protonated and alkali-cationized Boc-N-protected hybrid peptides containing repeats of D-Ala-APyC and APyC-D-Ala: formation of [b(n-1) + OCH3 + Na]+ and [b(n-1) + OH + Na]+ ions

RATIONALE

Differentiation and structural characterization of positional isomers of non-natural amino acid hybrid peptides by using electrospray ionization tandem mass spectrometry (ESI-MS(n) ) is desirable because of their fundamental importance from the view point of peptide mass spectrometry and also of their increasing importance in the area of research towards biomedical and material applications; hence, the present study is undertaken.

METHODS

Electrospray ionization ion-trap tandem mass spectrometry (ESI-MS(n)) was used to characterize and differentiate three pairs of positional isomers of Boc-N-protected hybrid peptides containing repeats of D-Ala-APyC and APyC-D-Ala (D-Ala = D-alanine and APyC = trans-3-aminopyran-2-carboxylic acid).

RESULTS

ESI-MS(n) spectra of protonated and alkali-cationized positional isomeric peptides display characteristic fragmentation involving the peptide backbone, the Boc group, and the side chain. It is observed that abundant rearrangement ions [b(n-1) + OCH(3) + Na](+) or [b(n-1) + OH + Na](+) are formed when D-Ala is present at C-terminus and the presence of APyC at the C-terminus inhibits the formation of rearrangement ions. In addition, abundant b(n-1)(+) ions are formed, presumably with stable oxazolone structures, when the C-terminus of b(n-1) (+) ions possessed D-Ala.

CONCLUSIONS

The present study demonstrates that ESI tandem mass spectrometry is very useful for differentiating positional isomers of hybrid peptides containing D-Ala and APyC amino acids. While the protonated peptides give rise to characteristic sequencing ions, the cationized peptides produce additional rearrangement ions ([b(n-1) + OCH(3) + Na](+) and [b(n-1) + OH + Na](+)) which helps distinguish between the presence of D-Ala and APyC amino acids at the C-terminus.

Evaluation of microbial flora in chronic tonsillitis and the role of tonsillectomy

Objective: To establish a correlation between clinical picture and bacteriological findings in chronic tonsillitis and to study the efficacy of surface swabs in predicting tonsillar core bacteria.Design: A prospective study analyzing microbiological flora of 149 patients with chronic tonsillitis, 17 patients with acute tonsillitis, 34 control patients and 31 postoperative patients of tonsillectomy was conducted. Surface swabs and fine needle aspiration was done from the tonsils under anesthesia just prior to surgery. Excised tonsils were cultured. A postoperative   surface swab was taken in thirty one randomly selected patients three weeks after surgery.Results: Core cultures of 102 out of 149 patients (68%) were positive for pathogenic bacteria. Core pathogenic flora was mono microbial in nature. Staphylococcus aureus was the commonest cultured pathogen. When compared with tonsil core pathogens, surface swabs and fine needle   aspiration showed 77% and 93% correlation respectively. After tonsillectomy, elimination of pathogenic bacteria from the oropharynx was seen in 97% of the patients.Conclusion: Tonsillectomy eradicated pathogenic microflora from the oropharynx in almost in all patients. Surface swabs have a high degree of reliability and are a useful adjuvant investigation to supplement the clinical diagnosis and can be useful for decision making. DOI:http://dx.doi.org/10.3329/bjo.v18i2.11982 Bangladesh J Otorhinolaryngol 2012; 18(2): 109-113

Triple reinforcement of bronchial stump

Various methods are used to prevent bronchopleural fistula following anatomical lung resection, as bronchopleural fistula constitutes a life-threatening complication. Pleural flaps are less vascularized, whereas an intercostal muscle flap, although well vascularized, does not offer enough strength for repair. We describe here the use of pleural flaps to strengthen a bronchial closure and cover the defect. Subsequently, an intercostal muscle flap is buttressed over the bronchial stump.

Differentiation of Boc-protected alpha,delta-/delta,alpha- and beta,delta-/delta,beta-hybrid peptide positional isomers by electrospray ionization tandem mass spectrometry

Two new series of Boc-N-alpha,delta-/delta,alpha- and beta,delta-/delta,beta-hybrid peptides containing repeats of L-Ala-delta(5)-Caa/delta(5)-Caa-L-Ala and beta(3)-Caa-delta(5)-Caa/delta(5)-Caa-beta(3)-Caa (L-Ala = L-alanine, Caa = C-linked carbo amino acid derived from D-xylose) have been differentiated by both positive and negative ion electrospray ionization (ESI) ion trap tandem mass spectrometry (MS/MS). MS(n) spectra of protonated isomeric peptides produce characteristic fragmentation involving the peptide backbone, the Boc-group, and the side chain. The dipeptide positional isomers are differentiated by the collision-induced dissociation (CID) of the protonated peptides. The loss of 2-methylprop-1-ene is more pronounced for Boc-NH-L-Ala-delta-Caa-OCH(3) (1), whereas it is totally absent for its positional isomer Boc-NH-delta-Caa-L-Ala-OCH(3) (7), instead it shows significant loss of t-butanol. On the other hand, second isomeric pair shows significant loss of t-butanol and loss of acetone for Boc-NH-delta-Caa-beta-Caa-OCH(3) (18), whereas these are insignificant for its positional isomer Boc-NH-beta-Caa-delta-Caa-OCH(3) (13). The tetra- and hexapeptide positional isomers also show significant differences in MS(2) and MS(3) CID spectra. It is observed that 'b' ions are abundant when oxazolone structures are formed through five-membered cyclic transition state and cyclization process for larger 'b' ions led to its insignificant abundance. However, b(1)(+) ion is formed in case of delta,alpha-dipeptide that may have a six-membered substituted piperidone ion structure. Furthermore, ESI negative ion MS/MS has also been found to be useful for differentiating these isomeric peptide acids. Thus, the results of MS/MS of pairs of di-, tetra-, and hexapeptide positional isomers provide peptide sequencing information and distinguish the positional isomers.

Unusual presentations of thyroid malignancies - a case series

Unusual presentations of thyroid neoplasms have been reported from time to time. Four such cases of bizarre presentations of thyroid malignancies seen in the ENT Department of ESIC Hospital, K.K. Nagar, Chennai, India are presented. These cases highlight certain important issues concerning the diagnosis and management. A review of the literature on the subject is discussed.

Isolated tricuspid valve endocarditis in nonaddicted patients: a diagnostic challenge

Isolated native nonrheumatic tricuspid valve endocarditis rarely is described in the absence of intravenous drug use, intracardiac catheters, or cardiac anomalies. We diagnosed tricuspid valve endocarditis in two elderly nonaddicted patients with recurrent pulmonary infiltrates, anemia, and microscopic hematuria that occurred during several months and was caused by Gemella morbillorum and Candida glabrata, respectively. We have reviewed 27 other cases of nonaddicted patients with tricuspid valve endocarditis from the literature and discussed etiology, clinical characteristics, and outcome. Mean age was 53.5 years (range, 22 to 74 years old), and 72% had underlying medical conditions. Staphylococcus oureus, Streptococcus bovis, and candida species were the causative organisms in 70% of the cases. Average duration of infection before diagnosis was 9.3 months. We conclude that isolated tricuspid valve endocarditis in nonaddicted patients occurs mainly in the middle-aged and older persons, mimicking chronic illness and community-acquired pneumonia. In the absence of a history of intravenous drug use, diagnostic delays are common. We suggest that right-sided endocarditis must be considered in any patient with the "Tricuspid Syndrome," consisting of recurrent pulmonary events, anemia, and microscopic hematuria. Careful evaluation of prior medical records and clinical course can be very helpful. Echocardiography and serial blood cultures provide the key to diagnosis.

Thyroid surgery without drainage: 15 years of clinical experience

Drainage in thyroid surgery has been a routine but empirical practice with no scientific evidence to support its benefit. The largest series to date of non-drainage in thyroid surgery is presented, comprising 260 patients over a 15-year period. No case selection for non-drainage was employed. Two hundred and fifty-nine cases were not drained and included toxic goitres, and bilateral and redo procedures. There was one thyroid storm and two cases of subcutaneous fluid collection, treated by needle aspiration. No cases of recurrent laryngeal nerve injury, airway obstruction or death were recorded. This study strongly demonstrates the safety of non-drainage in routine thyroid surgery.