Biotechnological remediation of arsenate from aqueous solution using a novel bacterial strain: Isotherm, kinetics and thermodynamic studies.

Arsenic is a global environmental contaminant that imposes a big health threat which requires an immediate attention to clean-up the contaminated areas. This study examined the biosorption ability of a novel Bacillus strain for the removal of arsenate (pentavalent arsenic) from aqueous solution. The optimum biosorption condition was studied as a function of biomass dosage, contact time and pH. Dubinin-Radushkevich (D-R), Freundlich, and Langmuir models were applied in describing the biosorption isotherm. The maximal biosorption capacity (92%) was obtained at 25 °C, biomass concentration 2000 mg/L at pH value of 4 and contact period of 50 min. Strain 139SI act as an admirable host to the arsenate. Thermodynamic assessment (ΔG0, ΔH0, and ΔS0) also suggested the chemisorption and feasible process of As(V) biosorption. The reuse study illustrated the highest recovery of 93% using 1 M HCl, and a decrease of 25% in recovery of As(V) ions after 10 times desorption process.

The tick Ixodida: an unusual foreign body in the ear.

We report a patient with a hard tick in her left ear, adherent to the tympanic membrane.

Inhibition of Quorum Sensing-Controlled Virulence Factors and Biofilm Formation in Pseudomonas aeruginosa by Culture Extract from Novel Bacterial Species of Paenibacillus Using a Rat Model of Chronic Lung Infection.

Quorum sensing (QS) is a key regulator of virulence factors and biofilm formation in Gram-negative bacteria such as Pseudomonas aeruginosa. Microorganisms that inhabit soil are of strategic importance in the discovery of compounds with anti-QS properties. The objective of the study was to test the culture extract of a taxonomically novel species of Paenibacillus strain 139SI for its inhibitory effects on the QS-controlled virulence factors and biofilm formation of Pseudomonas aeruginosa both in vitro and in vivo. The Paenibacillus sp. culture extract was used to test its anti-QS effects on the LasA protease, LasB elastase, pyoverdin production, and biofilm formation of P. aeruginosa as well as evaluate its therapeutic effects on lung bacteriology, pathology, hematological profile, and serum antibody responses of experimental animals in a rat model of chronic lung infection. Results showed significant decrease in the activities of QS-controlled LasA protease, LasB elastase pyoverdin, and biofilm formation of P. aeruginosa caused by the culture extract. Moreover, the extract significantly prolonged the survival times of rats and facilitated the clearance of biofilm infections from infected lungs. In conclusion, the antiquorum sensing effects of culture extract from a novel species of Paenibacillus provide new insights to combat biofilm-associated infections.

Antibiofilm activity, compound characterization, and acute toxicity of extract from a novel bacterial species of paenibacillus.

The effectiveness of many antimicrobial agents is currently decreasing; therefore, it is important to search for alternative therapeutics. Our study was carried out to assess the in vitro antibiofilm activity using microtiter plate assay, to characterize the bioactive compounds using Ultra Performance Liquid Chromatography-Diode Array Detection and Liquid Chromatography-Mass Spectrometry and to test the oral acute toxicity on Sprague Dawley rats of extract derived from a novel bacterial species of Paenibacillus strain 139SI. Our results indicate that the crude extract and its three identified compounds exhibit strong antibiofilm activity against a broad range of clinically important pathogens. Three potential compounds were identified including an amino acid antibiotic C8H20N3O4P (MW 253.237), phospholipase A2 inhibitor C21H36O5 (MW 368.512), and an antibacterial agent C14H11N3O2 (MW 253.260). The acute toxicity test indicates that the mortality rate among all rats was low and that the biochemical parameters, hematological profile, and histopathology examination of liver and kidneys showed no significant differences between experimental groups (P > 0.05). Overall, our findings suggest that the extract and its purified compounds derived from novel Paenibacillus sp. are nontoxic exhibiting strong antibiofilm activity against Gram-positive and Gram-negative pathogens that can be useful towards new therapeutic management of biofilm-associated infections.

Iatrogenic submandibular duct rupture complicating sialography: a case report.

INTRODUCTION: Sialolithiasis is the most common disease of salivary glands. Sialography is particularly important for the assessment of the outflow tract and in diagnosing obstructive salivary gland lesions including calculi. CASE PRESENTATION: We report on a 38-year-old female with sialolithiasis whom had Wharton's duct perforation, complicating the sialography. She was treated conservatively with a course of co-amoxiclav, oral prednisolone for three days and pain-killers. The patient was clinically well on follow-up reassessments at the end of the first week and three weeks post procedure. CONCLUSIONS: Perforation of salivary duct complicating the sialography is rare. Awareness of this potential complication and utilizing a good sialography technique need to be advocated amongst radiologists. Response to treatment by conservative management is preferred as illustrated in this case.

Iatrogenic aspiration of custom-made keel: a case report.

INTRODUCTION: Laryngeal stenosis has various causes and treatment options. Endoscopic resection of the stenotic part with CO2 laser is one of the treatment options of laryngotracheal stenosis. Keels are useful for preventing adhesion formation, restenosis and web formation, which may happen during the later stage. They can be put in place either via the endoscopic approach or through a micro thyroidotomy and are held in place with a heavy suture through cricothyroid and thyrohyoid membranes. They are left in place for two to four weeks, and then removed through the endoscopic approach under general anesthetics. CASE PRESENTATION: We report on a case of anterior glottis stenosis with keel aspiration for two weeks, after endoscopic CO2 laser resection of the stenotic section and keel placement. The patient was admitted to our center, where bronchoscopy was performed and the keel was removed. A new custom-made silastic keel was properly placed in raw areas and fixed to the skin with suture through the cricothyroid and thyrohyoid membranes. The keel was removed three weeks later. CONCLUSIONS: Endoscopic keel placement should be done with heavy suture through cricothyroid and thyrohyoid membranes. Surgeons should suture the keel to the anterior laryngeal wall with specially designed Lichtenberger's needle-carriers to prevent complications such as keel aspiration, adhesion formation and imposing a second trip under general anesthetics, which put the patient at increased risk. The false vocal cord microflaps, as biological keels and a relatively new method may replace silastic keel placement in the future.

Velopharyngeal and choanal stenosis after radiotherapy for nasopharyngeal carcinoma.

Choanal stenosis is a well recognized late complication of radiotherapy for nasopharyngeal carcinoma. However velopharyngeal stenosis post radiotherapy for nasopharyngeal carcinoma is rare. We present here a case of bilateral choanal stenosis and velopharyngeal stenosis in a patient treated with radiotherapy for nasopharyngeal carcinoma. A 58-year-old woman presented to our otolaryngology clinic with a one year history of nasal obstruction. She was diagnosed to have nasopharyngeal carcinoma 12 years ago for which she received radiotherapy. Clinical examination revealed bilateral choanal stenosis and velopharyngeal stenosis. Treatment of choanal stenosis and velopharyngeal stenosis is challenging due to high incidence of recurrence and patients frequently require multiple procedures. The patient underwent a transnasal endoscopic excision of velopharyngeal scar tissue and widening of posterior choana using Surgitron®, mitomycin-C applied topically to the surgical wound and bilateral stenting under general anesthesia. The stents were kept for two weeks, and 3 years post operation velopharyngeal aperture and posterior choana remained patent. As illustrated in this case velopharyngeal stenosis can occur after radiotheraphy and should not be overlooked. Combine modality of transnasal endoscopic excision of velopharyngeal scar tissue, widening of choanal stenosis with Surgitron® followed by the application of mitomycin-C and stenting has been shown to be an effective option.

Evidence of Bacterial Biofilms among Infected and Hypertrophied Tonsils in Correlation with the Microbiology, Histopathology, and Clinical Symptoms of Tonsillar Diseases.

Diseases of the tonsils are becoming more resistant to antibiotics due to the persistence of bacteria through the formation of biofilms. Therefore, understanding the microbiology and pathophysiology of such diseases represent an important step in the management of biofilm-related infections. We have isolated the microorganisms, evaluated their antimicrobial susceptibility, and detected the presence of bacterial biofilms in tonsillar specimens in correlation with the clinical manifestations of tonsillar diseases. Therefore, a total of 140 palatine tonsils were collected from 70 patients undergoing tonsillectomy at University Malaya Medical Centre. The most recovered isolate was Staphylococcus aureus (39.65%) followed by Haemophilus influenzae (18.53%). There was high susceptibility against all selected antibiotics except for cotrimoxazole. Bacterial biofilms were detected in 60% of patients and a significant percentage of patients demonstrated infection manifestation rather than obstruction. In addition, an association between clinical symptoms like snore, apnea, nasal obstruction, and tonsillar hypertrophy was found to be related to the microbiology of tonsils particularly to the presence of biofilms. In conclusion, evidence of biofilms in tonsils in correlation with the demonstrated clinical symptoms explains the recalcitrant nature of tonsillar diseases and highlights the importance of biofilm's early detection and prevention towards better therapeutic management of biofilm-related infections.

Base of tongue tuberculosis: a case report.

We report a rare case of base of tongue tuberculosis following pulmonary tuberculosis. Patient presented to us with chief complaints of sore throat and pain on swallowing for period of 3 months. On examination with 70 degree telescope, we observed an ulcer on right side of base of tongue. The edges of the ulcer appeared to be undermined with whitish slough at the centre of the ulcer. Examination of neck showed a multiple small palpable middle deep cervical lymph nodes on right side of neck. Biopsy of the ulcer was taken, which showed granulomatous inflammation, suggestive of tuberculosis. Laboratory investigations revealed a raise in erythrocyte sedimentation rate, sputum for acid fast bacilli was strongly positive. Chest X ray was performed for patient showed multiple areas of consolidation. Patient was referred to chest clinic for further management of tuberculosis and was started on anti-tuberculous drugs. In conclusion tuberculosis of oral cavity is rare, but should be considered among one of the differential diagnosis of the oral lesions and biopsy is necessary to confirm the diagnosis.

Radiological analysis of the ethmoid roof in the Malaysian population.

OBJECTIVE: To ascertain the prevalence of the lateral lamella of the cribriform plate height according to Keros classification in the Malaysian population, and to find if there is any difference between the major ethnic groups in Malaysia (Malay, Chinese, Indian). METHODS: Retrospective analysis of 150 CT scan studies of the paranasal sinuses. RESULTS: The mean height of the lateral lamella of the cribriform plate (LLCP) in 300 sides was 2.64mm. Keros type I was seen in 240 sides (80%), while, Keros type II was seen in 60 sides (20%). There was no significant difference in the distribution of Keros classification among the major ethnic groups of Malaysia (Malay, Chinese, Indian). Keros type I was seen in 103 sides in males and 137 sides in females. Significant difference was observed in type II between the male and female (47 sides in males and 13 sides in female; p-value <0.001). When comparing the difference in the height of the LLCP in the same individual, asymmetry was observed in 139 patients. The LLCP height was higher on the left side in 71 patients and higher on the right in 68. CONCLUSION: The understanding of the anatomy of the ethmoid roof with its possible variation is crucial to give the surgeon the optimal information about the possible risk that one can face during the surgery.

Hearing loss after noise exposure.

The higher field strength magnetic resonance imaging (MRI) such as 3 Tesla (T) and above generates noise that has potential detrimental effects on the hearing. Temporary threshold shifts following MRI examination have been reported for MRI with lower field strength. Such effect, however, have not been reported so far for a 3T MRI. We report a case that exemplifies the possible detrimental effects of a 3 T MRI generated noise on the auditory system. Our patient underwent investigation of his chronic backache in a 3 T MRI unit and developed hearing loss and tinnitus post-MRI examination. Hearing assessment was done using pure tone audiogram, distortion product otoacoustic emission (DPOAE) and brainstem electrical response audiometry (BERA) which revealed a unilateral sensorineural hearing loss which recovered within 3 days. However the tinnitus persisted. This is possibly a case of temporary threshold shift following noise exposure. However a sudden sensorineural hearing loss remains the other possibility.

Suction elevator for ear surgery.

An instrument has been designed to combine a suction and an elevator for use in ear surgery.

Nose pads.

An idea to fix broken nose pads of spectacles has been suggested.

Low lying larynx.

We report a rare case of laryngotracheal anomaly and its possible etiology and mode of presentation. A teenager presented with voice change and a neck lump. Investigations revealed a laryngeal anomaly in which the larynx was hyperdescended. It was accompanied by low lying thyroid gland and hyoid bone together with an absence of a cervical segment of the esophagus and trachea. The anomaly only became noticeable secondary to pubertal changes in the thyroid cartilage of the teenager. An embryological defect during the formation of the laryngotracheal tube and esophagus is a possible explanation of this anomaly. The present case probably represents the third reported of its kind.