Genomic analysis, simultaneous production, and process optimization of extracellular polymeric substances and polyhydroxyalkanoates by Methylobacterium sp. ISTM1 by utilizing molasses.

In the current study, the isolated Methylobacterium sp. ISTM1 simultaneously produced both extracellular polymeric substances (EPS) and polyhydroxyalkanoates (PHA) in a single-step process. The yield of biopolymers (EPS and PHA) was enhanced by optimizing the process parameters of EPS and PHA production. Methylobacterium sp. ISTM1 was able to produce 7.18 ± 0.04 g L-1 EPS and 1.41 ± 0.04 g L-1 PHA simultaneously at optimized culture conditions i.e., 9% molasses and pH 7. The genomic analysis of the strain has identified the involved genes and pathways in the production of EPS and PHA. Both the biopolymers were found non-toxic according to the cytotoxicity analysis. The results of the current study present the potential of the bacterium Methylobacterium sp. ISTM1 produces non-toxic biopolymers by utilizing agro-industrial waste (molasses) that can be harnessed sustainably for various applications.

Biosorption of Cr (VI) from aqueous solution by extracellular polymeric substances (EPS) produced by Parapedobacter sp. ISTM3 strain isolated from Mawsmai cave, Meghalaya, India.

In the current study, EPS producing strain Parapedobacter sp. ISTM3 was isolated from Mawsmai cave, Meghalaya, India. The strain ISTM3 showed enhanced EPS production (4.65 ± 0.10 g L-1) at optimized parameters, i.e., pH 8 and 3% molasses as a carbon source. The extracted EPS was structurally characterized by GC-MS, NMR, and FTIR analysis to investigate its monomer compositions, functional groups, and linkage analysis. GC-MS study confirmed the heteropolymeric nature of EPS, whereas the FTIR study confirmed the presence of an aliphatic group, amine group, uronic acid, and saccharides group in the EPS structure. Biosorption of heavy metals by EPS from an aqueous solution was investigated by using heavy metals mixture (Zn2+, Cu2+, Pb2+, Cr6+, Fe2+, and Cd2+) with 20 mg L-1 concentration of each metal. EPS showed the highest removal efficiency and metal adsorption capability for Cr6+ as compared to other heavy metals studied. Also, metal adsorption capability (19.032 mg g-1) and removal efficiency (95.10%) of Cr6+ by EPS were further increased in acidic conditions (pH 5.0). FTIR and SEM-EDX analysis confirmed the biosorption mechanism of EPS. The Freundlich and Langmuir adsorption isotherms were employed to discover the biosorption parameters for Cr6+ uptake with a concentration range of 10-200 mg L-1 by EPS (1 g L-1). The Langmuir model was found to better fit the Cr6+ adsorption by EPS having a maximum adsorption capacity of 33.783 mg g-1. With this, the present study highlights the EPS production potential of Parapedobacter sp. ISTM3, as well as the potential of extracted EPS for heavy metals removals via adsorption.

Synthesis of calcite-based bio-composite biochar for enhanced biosorption and detoxification of chromium Cr (VI) by Zhihengliuella sp. ISTPL4.

The current study presents a comprehensive analysis of the potential of actinobacterium Zhihengliuella sp. ISTPL4 and different composite materials for the removal of hexavalent chromium [Cr (VI)]. Genome analysis of strain indicated the presence of several oxidoreductases which includes chromate reductase, nitrate reductase, thioredoxin, superoxide dismutase and hydrogenase are other major candidate genes. Catalytic calcite-based bio-composite material was absorbed on biochar had highest Cr removal efficiency. The main mechanism involved in Cr biosorption by this strain was explained by the Langmuir isotherm model; under equilibrium conditions the maximum adsorption was observed 49 ± 0.3 mgg-1. Kinetic studies showed that biosorption of Cr (VI) by this strain was a rate-limiting step and followed a pseudo-second-order kinetics (R2 = 0.99). SEM analysis is in line with EDX result indicating highest Cr removal by calcined biochar. MTT assay shown that the bacteria successfully convert toxic Cr (VI) to comparatively less toxic form such as Cr (III).

Computational analysis of conserved coil functional residues in the mitochondrial genomic sequences of dermatophytes.

Dermatophyte is a group of closely related fungi that have the capacity to invade keratinized tissue of humans and other animals. The infection known as dermatophytosis, caused by members of the genera Microsporum, Trichophyton, and Epidermophyton includes infection to the groin (tinea cruris), beard (tinea barbae), scalp (tinea capitis), feet (tinea pedis), glabrous skin (tinea corporis), nail (tinea unguium), and hand (tinea manuum). The identification of evolutionary relationship between these three genera of dermatophyte is epidemiologically important to understand their pathogenicity. Mitochondrial DNA evolves more rapidly than a nuclear DNA due to higher rate of mutation but is very less affected by genetic recombination, making it an important tool for phylogenetic studies. Thus, here we present a novel scheme to identify the conserved coil functional residues of Trichophyton rubrum, Trichophyton mentagrophytes, Epidermophyton floccosum and Microsporum canis. Protein coding sequences of the mitochondrial genome were aligned for their similar sequences and homology modelling was performed for structure and pocket identification. The results obtained from comparative analysis of the protein sequences revealed the presence of functionally active sites in all the species of the genera Trichophyton and Microsporum. However in Epidermophyton floccosum it was observed in three protein sequences of the five studied. The absence of these conserved coil functional residues in E. floccusum may be correlated with lesser infectivity of this organism. The functional residues identified in the present study could be responsible for the disease and thus can act as putative target sites for drug designing.

A rare presentation of pellet injury in the neck.

Penetrating neck injuries are dangerous and deserve emergency treatment by virtue of the vital structures present underneath. There is a potential risk of unrecognized vascular injury and retained foreign bodies with their associated complications in these wounds. Therefore, an early diagnostic workup to localize the site of injury and an immediate neck exploration are important.

An unusual orbital blow-out fracture: a case report.

The complete dislocation of the orbital contents into the maxillary antrum as a result of trauma is an extremely rare event and requires immediate exploration and repositioning of the globe with reconstruction of the orbital floor. We present the case of a 10-year-old male who sustained trauma to the orbit and was initially suspected to have developed auto-evisceration. He underwent successful exploration and reconstruction of orbital floor with remarkable improvement.

Duplication cyst of oesophagus: a case report.

Duplication of the oesophagus is the second most common duplication of the gastrointestinal tract. Children with oesophageal duplication cyst usually present with dysphagia or as asymptomatic thoracic mass found o incidental chest x-ray. We report a case of oesophageal duplication cyst that presented with inspiratory stridor and dyspnoea in a 6 month old boy. Bronchoscopy revealed an external compression on the trachea. Duplication cyst arising from the oesophagus was suggested on CT and MRI. The cyst was surgically excised with resolution of symptoms.

A study of voice changes in various phases of menstrual cycle and in postmenopausal women.

Larynx is responsible for the generation of voice and subsequently impacts on communication, social interaction, personality, and artistic expression. The vocal instrument is comprised of the vibratory body, the respiratory power source, and the oropharyngeal resonating chamber. The lungs are the power supply, the larynx is the vibratory source, and the supraglottal vocal tract (supraglottal pharynx oral cavity, nasal cavity) is the resonator that shapes the sound into words and songs. During the phase of expiration as the diaphragm relaxes and the chest wall recoils, air is pushed through the nearly closed vocal folds. The aerodynamic forces of the air column and myoelastic properties of the vocal folds are responsible for the repeated opening and closing of the glottal tissue that pulses that air column as it flows out. These disruptions in the steady state of tracheal air pressure by glottal activity and vocal fold vibrations result in voice production. Voice is characterized by its frequency intensity and harmonics. The harmonics are hormonally dependent. This is illustrated by changes that occur during male and female puberty. The female voice evolves from childhood to menopause under the varied influences of estrogen, progesterone, and testosterone. These hormones are the dominant factor in determining voice changes throughout life. Female voice has a fundamental frequency one-third lower than that of a child. In males, androgen released at puberty is responsible for the male vocal frequency being an octave lower than that of a child. The females have a reproductive system, which undergoes a regular cyclic change known as the menstrual cycle. Laryngeal changes are evident and fluctuate systematically during the reproductive years with the menstrual cycle. The main objective of this experiment is to provide a solid ground with evidence of changes in voice because of sexual hormones, which will form the base of a multidisciplinary approach to a comprehensive and integrated understanding of premenstrual and menopausal female voice.

Acinic cell carcinoma with extensive neuroendocrine differentiation: a diagnostic challenge.

Primary salivary gland carcinoma with neuroendocrine differentiation is of rare occurrence, especially so in the parotid gland. Amongst the various reported primary tumors with neuroendocrine differentiation, acinic cell carcinoma (ACC) one such tumor. A 48 year old lady presented with a gradually increasing right infra-auricular swelling for a period of 1 year which enlarged suddenly in a short period. Contrast Enhanced Computed Tomography (CECT) suggested diagnosis of Pleomorphic Adenoma. Fine Needle Aspiration Cytology (FANC) yielded a cystic fluid suggesting a possibility of Warthin's tumor or Oncocytic lesion. Intraoperative findings were suggestive of a Warthin's tumor. Initial histopathological examination of the tumor was suggestive of neuroendocrine carcinoma. However, extensive sectioning revealed peripheral islands of ACC. Immunoexpression of S-100, Neuron specific Enolase (NSE), Chromogranin A and Synaptophysin confirmed the diagnosis. The possibility of neuroendocrine differentiation in a primary salivary gland tumor should be kept in mind whenever a salivary gland tumor shows only neuroendocrine histology.

Cysticercosis of tongue - A case report.

Tongue is a rare site for cysticercosis cellulosae. Very few cases of solitary cysticercosis of tongue have been reported. We are reporting one such case. Also a review of reported cases in literature, etoipathogenesis, clinical course and management is being described.

Deep neck abscess: a prospective study of 54 cases.

Deep neck abscesses (DNAs) continue to be commonly encountered in developing countries like India. This study was conducted to determine the changing trends within our population with respect to presentation, aetiology, location and microbiology of DNAs. Fifty-four patients with DNAs who were managed at the Department of ORL and H&N Surgery in our hospital between May 2002 and December 2002 formed the basis of the study. We observed that the high incidence of DNAs could be attributed to lack of awareness, illiteracy and poverty among patients, along with the poor primary health infrastructure. We also recommend early surgical intervention in these cases to decrease the prevalence of complications.

Unusual complication of ingestion of a foreign body.

Foreign bodies of the upper aerodigestive tract are common problems dealt with by the otolaryngologist. Among all foreign bodies in the oesophagus, an open safety pin still presents a challenge for the ENT specialists because of its propensity to pierce the oesophagus and surrounding structures. We present an interesting case of a long-standing foreign body i.e. an open safety pin, which, after piercing the hypopharynx, caused fatal common carotid artery rupture.