Soluble expression and purification of a full-length asparaginyl tRNA synthetase from Fasciola gigantica

We report the molecular cloning, expression, and single-step homogeneous purification of a full-length asparaginyl tRNA synthetase (NRS) from Fasciola gigantica (FgNRS). Fasciola gigantica is a parasitic liver fluke of the class Trematoda. It causes fascioliasis that infects the liver of various mammals, including humans. Aminoacyl tRNA synthetases (AARS) catalyze the first step of protein synthesis. They attach an amino acid to its cognate tRNA, forming an amino acid-tRNA complex. The gene that codes for FgNRS was generated by amplification by polymerase chain reaction. It was then inserted in the expression vector pQE30 under the transcriptional control of the bacteriophage T5 promoter and lac operator. M15 Escherichia coli strain transformed with the FgNRS expression vector pQE30-NRS accumulates large amounts of a soluble protein of about 61 kDa. The protein was purified to homogeneity using immobilized metal affinity chromatography. The recombinant protein was further confirmed by immunoblotting with anti-His antibody. Following size exclusion chromatography, the FgNRS was stable and observed to be a dimeric protein. In this study, the expression and purification procedures have provided a simple and efficient method to obtain full-length FgNRS in large quantities. This will provide an opportunity to study the structure, dynamics and function of NRS.

Spectroscopic properties of Sm3+ ions doped Alkaliborate glasses for photonics applications

A new series of Sm³⁺ doped alkaliborate glasses have been prepared by melt quenching technique and their structural and spectroscopic properties were analysed employing XRD, FTIR, optical absorption, photoluminescence and decay spectral measurements in order to explore their suitability for photonic applications. The amorphous nature have been confirmed through XRD analysis and the FTIR spectra reveal the presence of fundamental stretching and bending vibrations of the borate networks in the prepared glasses. From the absorption peak positions, bonding parameter (δ) values were calculated to examine the nature of the metal-ligand bond. The optical band gap (E_opt) corresponds to the direct and indirect allowed transitions and the Urbach energies (ΔE) were calculated from the absorption spectra to understand the electronic band structure of the studied glasses. The Judd-Ofelt (JO) intensity parameters Ω_λ (λ=2, 4 and 6) were determined to explore the symmetry of the ligand environment around the Sm³⁺ ions in the studied glasses. The luminescence spectra exhibit four emission bands in the visible region due to the ⁴G_5/2→⁶H_5/2, ⁶H_7/2, ⁶H_9/2 and ⁶H_11/2 transitions. The radiative parameters such as transition probability (A), stimulated emission cross-section (σ_P^E), branching ratios (β_R) and radiative lifetime (τ_R) have been determined from the luminescence spectra using JO theory to ensure the suitability of the studied glasses for optoelectronic applications. The luminescence spectra were characterized through CIE 1931 chromaticity diagram to examine the dominant emission color of the studied glasses. The lifetime values of the Sm³⁺ doped studied glasses pertaining to the ⁴G_5/2 excited level have been determined through decay curve measurements and the non-exponential decay curves were fitted to the Inokuti-Hirayama model to analyze the energy transfer mechanism between the nearby Sm³⁺ ions. The obtained results were discussed and compared with the similar reported glasses.

Oral neoplasms in pickhandle barracuda Sphyraena jello from India

We report the spontaneous occurrence of oral neoplasms in pickhandle barracuda Sphyraena jello Cuvier, 1829 from Parangipettai, on the southeast coast of India. A total of 11736 fish were examined, of which 43 were affected with oral tumours, with an overall prevalence of 0.37%. Gross and clinical symptoms included reddish to grayish-white distended tumourous growths on the gingiva, intra-oral bones and tongue. The tumours exhibited delayed eruption and intra- or extra-oral swelling, varied in consistency from extremely firm to fleshy and released mucinous material. The majority of tumours consisted of numerous clumped toothlets, but some included hardened tissues. Local area invasion/transmission was observed in most cases; however, necropsy examination revealed no gross evidence of distant metastasis into visceral organs. Radiographic examination of compound odontomas revealed distinct unilocular radio-opaque mini-toothlets surrounded by defined radiolucency, whereas complex odontomas exhibited unilocular and indistinct radio-opaque masses within a much more extensive radiolucent zone. Histopathologically, the intra-oral tumour lesions were characterized by numerous imperfect (germ) toothlets consisting of a disorganized combination of dental tissues: pulp tissues with manifested and predominantly mixed hard dental tissues of immature dentine and enamel, numerous small to large and round to polyhedral ossicles embedded in hypocellular fibrous stromal tissues and sparsely spaced bland spindloid cells with cleft-like spaces of loose mucoid stroma. Histochemically, the neoplastic lesions stained positive for periodic acid-Schiff and Masson's trichrome. Based on the clinical and histological findings, the tumours were diagnosed as compound odontomas, complex odontomas, odontogenic myxomas, lingual myxomas and psammomatoid ossifying fibromas.

Methodology Considerations in Phase Mapping of Human Cardiac Arrhythmias

BACKGROUND

Phase analysis of cardiac arrhythmias, particularly atrial fibrillation, has gained interest because of the ability to detect organized stable drivers (rotors) and target them for therapy. However, the lack of methodology details in publications on the topic has resulted in ongoing debate over the phase mapping technique. By comparing phase maps and activation maps, we examined advantages and limitations of phase mapping.

METHODS AND RESULTS

Seven subjects were enrolled. We generated phase maps and activation maps from electrocardiographic imaging-reconstructed epicardial unipolar electrograms. For ventricular signals, phase was computed with (1) pseudoempirical mode decomposition detrending and (2) a novel Moving Average (MVG) detrending approach. For atrial fibrillation signals, MVG was modified to incorporate dynamic cycle length (DCL) changes (MVG-DCL). Phase maps were visually analyzed to study phase singularity points and rotors. Results show that phase is sensitive to cycle length choice, a limitation that was addressed by the MVG-DCL algorithm. MVG-DCL was optimal for atrial fibrillation analysis. Phase maps helped to highlight high-curvature wavefronts and rotors. However, for some activation patterns, phase generated nonrotational singularity points and false rotors.

CONCLUSIONS

Phase mapping computes singularity points and visually highlights rotors. As such, it can help to provide a clearer picture of the spatiotemporal activation characteristics during atrial fibrillation. However, it is advisable to incorporate electrogram characteristics and the time-domain activation sequence in the analysis, to prevent misinterpretation and false rotor detection. Therefore, for mapping complex arrhythmias, a combined time-domain activation and phase mapping with variable cycle length seems to be the most reliable method.

Comparison of compressive strength among three different intracanal post materials in primary anterior teeth: An in vitro study

Objective:

The objective of our study was to compare the fracture resistance and the mode of failure among three different post materials in primary anterior teeth.

Materials and Methods:

A total of sixty extracted primary anterior teeth were selected for the study. The samples were divided into three groups of twenty teeth each: Group I (Ribbond), Group II (Omega loop), and Group III (Glass fiber post). Pulp therapy was followed by intracanal post and crown buildup. The samples were mounted in self-cure acrylic and subjected to compressive strength test using universal testing machine (Instron). The maximum force at which the tooth fractured was recorded.

Results:

The values were subjected to one-way analysis of variance. The mean compressive strength values of Ribbond, omega loop, and glass fiber post were found to be 83.25 N, 61.60 N, and 75.55 N, respectively. The P value was found to be 0.220.

Conclusion:

Group I (Ribbond) showed the highest fracture resistance values followed by Group III (Glass fiber post) and Group II (Omega loop). Although there is difference in mean values, they were nonsignificant.

Electrophysiologic substrate in congenital Long QT syndrome: noninvasive mapping with electrocardiographic imaging (ECGI)

BACKGROUND

Congenital Long QT syndrome (LQTS) is an arrhythmogenic disorder that causes syncope and sudden death. Although its genetic basis has become well-understood, the mechanisms whereby mutations translate to arrhythmia susceptibility in the in situ human heart have not been fully defined. We used noninvasive ECG imaging to map the cardiac electrophysiological substrate and examine whether LQTS patients display regional heterogeneities in repolarization, a substrate that promotes arrhythmogenesis.

METHODS AND RESULTS

Twenty-five subjects (9 LQT1, 9 LQT2, 5 LQT3, and 2 LQT5) with genotype and phenotype positive LQTS underwent ECG imaging. Seven normal subjects provided control. Epicardial maps of activation, recovery times, activation-recovery intervals, and repolarization dispersion were constructed. Activation was normal in all patients. However, recovery times and activation-recovery intervals were prolonged relative to control, indicating delayed repolarization and abnormally long action potential duration (312±30 ms versus 235±21 ms in control). Activation-recovery interval prolongation was spatially heterogeneous, with repolarization gradients much steeper than control (119±19 ms/cm versus 2.0±2.0 ms/cm). There was variability in steepness and distribution of repolarization gradients between and within LQTS types. Repolarization gradients were steeper in symptomatic patients (130±27 ms/cm in 12 symptomatic patients versus 98±19 ms/cm in 13 asymptomatic patients; P<0.05).

CONCLUSIONS

LQTS patients display regions with steep repolarization dispersion caused by localized action potential duration prolongation. This defines a substrate for reentrant arrhythmias, not detectable by surface ECG. Steeper dispersion in symptomatic patients suggests a possible role for ECG imaging in risk stratification.

Infestation of Lernaeenicus seeri (Copepoda: Pennellidae) and Hirudinella ventricosa (Digenea: Hirudinellidae) on wahoo Acanthocybium solandri collected from Parangipettai, southeast coast of India

A commercially important fish, wahoo Acanthocybium solandri (Cuvier, 1832) (Scombridae), was collected to study the infestation of parasites from Parangipettai landing center, Tamil Nadu, southeast coast of India for a period of one year from January to December 2011. A total of 644 fish were captured and screened for parasites. Off 644 fish, 270 were infested by a parasitic copepod Lernaeenicus seeri Kirtisinghe, 1934 (Siphonostomatoida: Pennellidae) on the body surface. It is a mesoparasite, since the head and neck are inserted and attached to the muscle by making a wound/hole on the body and the rest of the parasite body with the egg sacs hanging outside. Prevalence was recorded as 42.29% with mean and maximum intensity at 3.22 and 33, respectively. Seasonal study showed that the prevalence was highest (62.82 %) during postmonsoon. Simultaneously, some of the fish (n = 144) were internally observed for the presence of parasites and we found that 101 fish were infested with an endoparasite digenean Hirudinella ventricosa (Pallas, 1774) (Hirudinellidae) in the stomach. Prevalence was recorded as 70.9%, and mean intensity of 1.62 and maximum intensity of 3 were also noted. The overall percentage of both copepod and digenean infestation were recorded as 60.42%. The infestation was high in postmonsoon season for both parasites. This is the first record of L. seeri from Indian waters and the second record of occurrence worldwide. Significant interactions were observed between season and infestation of both parasites (P<0.05).

Occurrence of heavy copepod infestation on Hemiramphus lutkei and double parasitisms on Hemiramphus far with copepod (Lernaeenicus hemiramphi) and isopod (Mothocya plagulophora)

In the present study about, 66 copepod parasites of Lernaeenicus hemiramphi of two Hemiramphus sp., H. far (17 copepod) and H. lutkei (49 copepod), and an isopod (Mothocya plagulophora) on the gill chamber were observed. H. lutkei was added as a new host for L. hemiramphi. The copepod infestation was almost on the ventral side of the hosts.

Occurrence of isopod Nerocila phaiopleura infestation on Whitefin wolf-herring (Chirocentrus nudus) from Southeast coast of India

The present study reported the first observation of isopod parasite, Nerocila phaiopleura infestation on Chirocentrus nudus an economically important fish from Cuddalore coast, Southeast coast of India. The maximum prevalence of 6.3 % and mean intensity of 3.2 were observed during pre-monsoon 2010 and monsoon 2010 respectively. The highest intensity 7 was observed in the single host during monsoon. The site of attachment leads to wound and offer the secondary infection. Two pathogenic bacteria Streptococcus aureus and E. coli were isolated from the wound.

A study on knowledge, attitude and practice regarding voluntary blood donation among medical students in Puducherry, India

Knowledge, attitude and practice studies have been used to understand the various factors that influence blood donation which is the basis for donor mobilization and retention strategies. Role of youngsters in voluntary blood donation is crucial to meet the demand of safe blood. The present study was aimed to assess the level of knowledge, attitude and practice regarding voluntary blood donation among the health care students. A validated and pre-tested questionnaire on knowledge, attitude and practice on blood donation were assessed among 371 medical students from Sri Lakshmi Narayana Institute of Medical Sciences and Research Institute, Puducherry, India. Result showed that knowledge on blood donation among respondents was 44.8% (1st year 36.7%, 2nd year 42.8% and 3rd year 54.9%). About 62.6% of non-donors (1st year 51%, 2nd year 61% and 3rd year 77%) showed positive attitude by expressing their willingness to donate blood while 22.8%.of the non-donors had negative attitude (1st year 33%, 2nd year 23% and 3rd year 13%). In practice 13.2% of students had donated blood (1st year 10%, 2nd year 13% and 3rd year 24%), in which 2.7% of male students alone donating blood on regular basis. Over all 3rd year student showed significantly higher knowledge compared with 1st years, in attitude and practice section 3rd year student's showed significantly higher positive attitude and practice than that of 1st and 2nd years. The present study reveals that there is a positive association among knowledge, attitude and practice on blood donation, which suggest that positive attitude and practice can be improved by inculcating knowledge on blood donation among college students to recruit and donate blood regularly, which will help to achieve 100% of blood donation on voluntary basis.

Occurrence of tumour (odontoma) in marine fish Sphyraena jello from the southeast coast of India

We examined the occurrence of odontoma in the marine fish Sphyraena jello sourced from 3 different landing centers (Cuddalore, Parangipettai and Nagapattinam) in Tamil Nadu (southeast India). A total of 19783 fishes were examined for odontoma presence, of which 2393 were affected with odontoma. The overall prevalence was 12.1% among the 3 stations. Fish landed at Parangipettai showed the highest peak prevalence of odontoma (16.8%) during the pre-monsoon, followed by Nagapatinam (9.1%) during summer 2011. The tumour lengths in premaxilla, supermaxilla and dentary bone were 1.1-3.6, 1.4-5.9 and 1.2-4.1 cm, respectively, and tumour widths were 0.3-1.9, 0.7-3.1 and 0.5-1.9 cm. Higher prevalence (0.206%) of tongue tumour along with odontoma was observed at Nagapattinam whereas it was lower (0.162%) at Cuddalore. Odontoma histopathology showed dense fibrous tissue with fine teeth roots. TEM analysis showed virus-like particles associated with odontoma. Radiography of the odontoma showed that the tumour masses were bony in nature and tissues were merged with upper and lower jaw.

Morphometry examination of placenta in birth weight of full-term newborns in Puducherry, India

irth weight is an important determinant of child survival, healthy growth and development. Low birth weight is a well-established risk factor for adverse long term health, particularly cardiovascular disease and metabolic syndrome. The ability of the fetus to grow and thrive in utero is presumed to be a function of the placenta. The present study was aimed to assess the morphometry examination of placenta in normal and low birth weight babies in the Union territory of Puducherry. Morphometry examination includes Placenta weight, number of cotyledons, maternal and fetal surface area and site of umbilical cord insertion were measured in normal and low birth weigh babies. Result showed among 200 subjects, mean birth weight of normal and low birth babies were 2806 and 2058 g, respectively. The prevalence rate of low birth babies (less than 2500 g) was 22%. The placental morphometry study namely placental weight, number of cotyledons, maternal and fetal surface area and insertion of umbilical cord at centre were significantly (p<0.001) reduced in the low birth weight babies when compared with normal birth weight babies. Study revealed that morphometry analysis of placenta significantly influences the birth weight of new born. In conclusion, study recommends the early measurements of placenta by non-invasive techniques like ultrasonography will be helpful in early prediction of low birth weight fetus in utero itself and for better management to avoid such low birth weight.

Fungal keratitis caused by Macrophomina phaseolina - A case report

A 70 year old female patient presented with complaints of pain, watering and swelling in the right eye. She gave a history of fall, as she was walking in the paddy field of her farm. Ophthalmological and Microbiological investigation revealed a fungal keratitis with an unusual fungus Macrophomina phaseolina which is primarily a plant pathogen, with a potential to cause human infections especially in immuno-compromised patients. The patient responded well to the antifungal treatment with Oral Voriconazole with absence of recurrence and dissemination.

Efficient synthesis of silver nanoparticles from Prosopis juliflora leaf extract and its antimicrobial activity using sewage

In this paper, aqueous extract of fresh leaves of Prosopis juliflora was used for the synthesis of silver (Ag) nanoparticles. UV-Vis spectroscopy studies were carried out to asses silver nanoparticles formation within 5 min, scanning electron microscopic was used to characterize shape of the Ag nanoparticles, X-ray diffraction analysis confirms the nanoparticles as crystalline silver and facecentered cubic type and Fourier transform infra-red assed that shows biomolecule compounds which are responsible for reduction and capping material of silver nanoparticles. The anti microbial activity of silver nanoparticle was performed using sewage. The approach of plant-mediated synthesis appears to be cost efficient, eco-friendly and easy methods.

Noninvasive electroanatomic mapping of human ventricular arrhythmias with electrocardiographic imaging

The rapid heartbeat of ventricular tachycardia (VT) can lead to sudden cardiac death and is a major health issue worldwide. Efforts to identify patients at risk, determine mechanisms of VT, and effectively prevent and treat VT through a mechanism-based approach would all be facilitated by continuous, noninvasive imaging of the arrhythmia over the entire heart. Here, we present noninvasive real-time images of human ventricular arrhythmias using electrocardiographic imaging (ECGI). Our results reveal diverse activation patterns, mechanisms, and sites of initiation of human VT. The spatial resolution of ECGI is superior to that of the routinely used 12-lead electrocardiogram, which provides only global information, and ECGI has distinct advantages over the currently used method of mapping with invasive catheter-applied electrodes. The spatial resolution of this method and its ability to image electrical activation sequences over the entire ventricular surfaces in a single heartbeat allowed us to determine VT initiation sites and continuation pathways, as well as VT relationships to ventricular substrates, including anatomical scars and abnormal electrophysiological substrate. Thus, ECGI can map the VT activation sequence and identify the location and depth of VT origin in individual patients, allowing personalized treatment of patients with ventricular arrhythmias.