Partial arytenoidectomy with transoral vocal fold lateralisation in treating airway obstruction secondary to bilateral vocal fold immobility.

OBJECTIVE: To report the outcome of 18 patients with a tracheostomy secondary to bilateral vocal fold immobility, who were managed using reconstructive transoral laser microsurgical techniques. METHODS: A retrospective review was conducted of the surgical outcome of 18 patients with bilateral vocal fold immobility and a tracheostomy resulting from different aetiologies. Follow-up duration ranged from one to five years. RESULTS: A total of 18 patients had a tracheostomy at presentation because of bilateral true vocal fold immobility and stridor. All cases were treated using reconstructive transoral laser microsurgery with arytenoidectomy and vocal fold lateralisation. All patients were successfully decannulated by eight weeks after surgery. CONCLUSION: Reconstructive transoral laser microsurgery using partial arytenoidectomy with vocal fold lateralisation is minimally invasive, feasible, safe and effective for airway reconstruction in patients who present with stridor due to bilateral true vocal fold immobility.

Molecular Study of Acinetobacter baumannii that Lacking Some Essentials Genes Responsible of Toxin-Antitoxin System.

Acinetobacter genus has various species that are widespread in different environments and can exist in non-living environment samples as well. Acinetobacter baumannii (A. baumannii) is known to be one of the main causes of nosocomial infection. Few studies have examined the possibility of the presence of this opportunistic pathogen in non-living environment samples. In this study, A. baumannii strain cl-2 was isolated from dishwasher basket samples and it was identified by 16S ribosomal RNA sequencing analysis. The present study also investigated the presence of some important genes responsible for toxin-antitoxin (TA) systems necessary for the resistance of this bacterium in improper environmental conditions. Additionally, attempts were made to study some essential virulence factors, such as hemolysin, lipase, protease, and lecithinase production, as well as biofilm formation and surface motility. The findings revealed that the isolate belongs to the A. baumannii strain cl-2. The isolate was deposed in the National Center for Biotechnology Information, (NCBI) and the data can be accessed via the NCBI accession number (MW642251). The results of screening the TA system by higBA, mazEF, and relBE genes showed the isolate did not contain these genes. The hemolysin toxin activity (phenotypic test) was performed by using the streaking and spot methods on blood agar. It was found that the A. baumannii strain cl-2 had the ability to hemolyze red blood cells and produce lecithinase and protease enzymes. Finally, it was revealed that the A. baumannii strain cl-2 had surface motility based on the concentric diffusion ring of growth observed on Luria Broth agar (0.3%). In conclusion, the isolates under study showed association patterns between their ability to produce hemolysin, lipase, lecithinase, as well as protease, and other virulence factors, including surface motility and biofilm formation.

Identifying a stochastic clock network with light entrainment for single cells of Neurospora crassa.

Stochastic networks for the clock were identified by ensemble methods using genetic algorithms that captured the amplitude and period variation in single cell oscillators of Neurospora crassa. The genetic algorithms were at least an order of magnitude faster than ensemble methods using parallel tempering and appeared to provide a globally optimum solution from a random start in the initial guess of model parameters (i.e., rate constants and initial counts of molecules in a cell). The resulting goodness of fit [Formula: see text] was roughly halved versus solutions produced by ensemble methods using parallel tempering, and the resulting [Formula: see text] per data point was only [Formula: see text] = 2,708.05/953 = 2.84. The fitted model ensemble was robust to variation in proxies for "cell size". The fitted neutral models without cellular communication between single cells isolated by microfluidics provided evidence for only one Stochastic Resonance at one common level of stochastic intracellular noise across days from 6 to 36 h of light/dark (L/D) or in a D/D experiment. When the light-driven phase synchronization was strong as measured by the Kuramoto (K), there was degradation in the single cell oscillations away from the stochastic resonance. The rate constants for the stochastic clock network are consistent with those determined on a macroscopic scale of 107 cells.

An unusual cause of a common presentation: a case of metastatic basal cell carcinoma.

Metastasis of basal cell carcinoma is exceedingly rare and usually not considered in the differential diagnosis of neck lumps. We present a case highlighting the importance of a thorough history and consideration of metastatic basal cell carcinoma in patients with a basaloid metastasis and an unknown primary.

Ensemble methods for stochastic networks with special reference to the biological clock of Neurospora crassa.

A major challenge in systems biology is to infer the parameters of regulatory networks that operate in a noisy environment, such as in a single cell. In a stochastic regime it is hard to distinguish noise from the real signal and to infer the noise contribution to the dynamical behavior. When the genetic network displays oscillatory dynamics, it is even harder to infer the parameters that produce the oscillations. To address this issue we introduce a new estimation method built on a combination of stochastic simulations, mass action kinetics and ensemble network simulations in which we match the average periodogram and phase of the model to that of the data. The method is relatively fast (compared to Metropolis-Hastings Monte Carlo Methods), easy to parallelize, applicable to large oscillatory networks and large (~2000 cells) single cell expression data sets, and it quantifies the noise impact on the observed dynamics. Standard errors of estimated rate coefficients are typically two orders of magnitude smaller than the mean from single cell experiments with on the order of ~1000 cells. We also provide a method to assess the goodness of fit of the stochastic network using the Hilbert phase of single cells. An analysis of phase departures from the null model with no communication between cells is consistent with a hypothesis of Stochastic Resonance describing single cell oscillators. Stochastic Resonance provides a physical mechanism whereby intracellular noise plays a positive role in establishing oscillatory behavior, but may require model parameters, such as rate coefficients, that differ substantially from those extracted at the macroscopic level from measurements on populations of millions of communicating, synchronized cells.

Uncoupling the solids retention times of flocs and granules in mainstream deammonification: A screen as effective out-selection tool for nitrite oxidizing bacteria.

This study focused on a physical separator in the form of a screen to out-select nitrite oxidizing bacteria (NOB) for mainstream sewage treatment. This separation relied on the principle that the NOB prefer to grow in flocs, while anammox bacteria (AnAOB) reside in granules. Two types of screens (vacuum and vibrating) were tested for separating these fractions. The vibrating screen was preferred due to more moderate normal forces and additional tangential forces, better balancing retention efficiency of AnAOB granules (41% of the AnAOB activity) and washout of NOB (92% activity washout). This operation resulted in increased NOB out-selection (AerAOB/NOB ratio of 2.3) and a total nitrogen removal efficiency of 70% at influent COD/N ratio of 1.4. An effluent total nitrogen concentration <10mgN/L was achieved using this novel approach combining biological selection with physical separation, opening up the path towards energy positive sewage treatment.

Impact of carbon to nitrogen ratio and aeration regime on mainstream deammonification.

While deammonification of high-strength wastewater in the sludge line of sewage treatment plants has become well established, the potential cost savings spur the development of this technology for mainstream applications. This study aimed at identifying the effect of aeration and organic carbon on the deammonification process. Two 10 L sequencing bath reactors with different aeration frequencies were operated at 25°C. Real wastewater effluents from chemically enhanced primary treatment and high-rate activated sludge process were fed into the reactors with biodegradable chemical oxygen demand/nitrogen (bCOD/N) of 2.0 and 0.6, respectively. It was found that shorter aerobic solids retention time (SRT) and higher aeration frequency gave more advantages for aerobic ammonium-oxidizing bacteria (AerAOB) than nitrite oxidizing bacteria (NOB) in the system. From the kinetics study, it is shown that the affinity for oxygen is higher for NOB than for AerAOB, and higher dissolved oxygen set-point could decrease the affinity of both AerAOB and NOB communities. After 514 days of operation, it was concluded that lower organic carbon levels enhanced the activity of anoxic ammonium-oxidizing bacteria (AnAOB) over denitrifiers. As a result, the contribution of AnAOB to nitrogen removal increased from 40 to 70%. Overall, a reasonably good total removal efficiency of 66% was reached under a low bCOD/N ratio of 2.0 after adaptation.

Effect of otitis media with effusion on cochlear implant surgery: technical difficulties, post-operative complications and outcome.

OBJECTIVE: This study evaluated the complications and outcomes of cochlear implantation in patients who had otitis media with effusion at the time of surgery. METHODS: A retrospective chart review study was performed of 87 consecutive paediatric patients (age range 22 months to 10 years, mean 4.8 years) who underwent successful cochlear implantation, with follow-up periods of 5-6 years. All patients had unilateral implants, with eight on the left side. All devices were activated two weeks after implantation. The effect of the middle-ear condition on the procedure, post-operative complications and outcome were evaluated. RESULTS: Unilateral ears of 17 otitis media with effusion patients were implanted with some surgical difficulties but no long-term post-operative complications. CONCLUSION: For children admitted for cochlear implantation who are subsequently found to have otitis media with effusion, surgeons should be aware of possible surgical difficulties. Greater intra-operative risks should be anticipated and more surgical time allowed for cochlear implantation in these patients.

Impact of the As Samra wastewater treatment plant upgrade on the water quality (COD, electrical conductivity, TP, TN) of the Zarqa River.

The impact of the As Samra wastewater treatment plant upgrade on the quality of the Zarqa River (ZR) water was investigated. Time series data that extend from October 2005 until December 2009 obtained by a state-of-the-art telemetric monitoring system were analyzed at two monitoring stations located 4 to 5 km downstream of the As Samra effluent confluence with the Zarqa River and about 25 km further downstream. Time series data that represent the ZR water quality before and after the As Samra upgrade were analyzed for chemical oxygen demand (COD), electrical conductivity (EC), total phosphorus (TP) and total nitrogen (TN). The means of the monitored parameters, before and after the As Samra upgrade, showed that the reductions in the COD, TP and TN were statistically significant, while no reduction in the EC was observed. Comparing the selected parameters with the Jordanian standards for reclaimed wastewater reuse in irrigation and with the Ayers & Westcot guidelines for interpretation of water quality for irrigation showed that the ZR water has improved towards meeting the required standards and guidelines for treated wastewater reuse in irrigation.

Artificial semi-rigid tissue sensitized with natural pigments: Effect of photon radiations.

BACKGROUND: A new approach for evaluating the optical penetration depth and testing its validity with Monte Carlo simulations and Kubelka-Munk theory is used for artificial semi-rigid tissue sensitized with natural pigments. Photodynamic therapy is a promising cancer treatment in which a photosensitizing drug concentrates in malignant cells and is activated by visible light at certain wavelength. MATERIALS AND METHODS: Cheap artificial semi-rigid tissue incorporated with scattering and absorbing materials along with some other composites comparable to normal human tissue has been performed. The optical parameters as measured with different conditions and calculated with various techniques are investigated. RESULTS: The probability of interaction of light with tissue is very high when exposed to light in presence of Cichorium pumilum and RBCs followed by photohemolysis or/and photodegradation. The optical penetration depth calculated by linear absorption coefficient ranges from 0.63 to 2.85 mm is found to be comparable to those calculated using Kubelka-Munk theory or Monte Carlo simulation (range from 0.78 to 2.42 mm). The ratio of absorption to the scattering is independent of thickness and decreases with increasing irradiation time. Moreover, the optical parameters as well as their ratios are in very good agreement in the two approaches of calculation. The values of absorption and scattering coefficients are independent of thickness. Furthermore, the average photon ranges in the samples containing no scattering and absorbing materials are about three times greater than those samples containing scattering materials. CONCLUSION: Our results suggest that light propagation with optical properties presented in this work could be applicable in diagnostic and therapeutic of the human biological tissue for photodynamic therapy.

Anaerobic treatment of strong sewage by a two stage system of AF and UASB reactors.

An anaerobic treatment system that consists of an Anaerobic Filter (AF) and an Upflow Anaerobic Sludge Blanket (UASB) in series was built and operated to investigate its performance in treating strong domestic wastewater with high suspended solids fraction under Jordan's ambient temperatures of 25 degrees C for summer and 18 degrees C for winter. The system was operated from September 2003 until early April 2004. The system was operated at a Hydraulic Retention Time (HRT) of 4 hours for the first stage AF and 8 hours for the second stage UASB. Average COD(t) and COD(ss) removal efficiencies of the AF/UASB were 58% and 81% respectively for the operation period. The results showed that the first stage AF was effective in removing suspended solids. In addition, hydrolysis, acidification and methanogenesis took place in the first stage AF which was advantageous to the second stage UASB. It was concluded that the AF/UASB system is effective in treating strong domestic wastewater with high suspended solids content under Jordan's ambient temperatures.

Retinoblastoma as a congenital primary intracranial tumor.

This report describes a rare case of retinoblastoma presenting as a congenital primary intracranial tumor. A 7-day-old infant presented with generalized seizures. He had a family history of retinoblastoma. Computed tomography of the brain revealed a midline suprasellar tumor without evidence of retinal tumors. Subtotal resection of the tumor was performed. Histopathologic findings were diagnostic of retinoblastoma. The patient sustained profound ischemic brain damage and was not given definitive further therapy. He died days after the diagnosis was made. Retinoblastoma can present as an isolated ectopic intracranial tumor without associated retinal tumors.

True caecal diverticulitis.

Nine patients (six females and three males), median age = 27.5 years (range 13-36) with caecal diverticulitis are presented. All underwent surgery with a suspected diagnosis of acute appendicitis. Per-operative diagnosis was possible in five cases, two cases were thought to have other benign pathology, but malignancy could not be excluded in the remaining two cases. Local excision was carried out in five cases, a right hemicolectomy was performed in the rest. Histology showed true diverticuli in eight cases, severity of the inflammation made it difficult to comment on the ninth case. Postoperative barium enema was carried out in six cases, which showed no further diverticuli in the colon. We conclude that preoperative diagnosis of caecal diverticulitis is difficult, and that true solitary caecal diverticuli present in a younger age group than the false caecal and ascending colon diverticuli and that they are probably congenital in origin.

Assessing the shape of root canals: an in vitro method using microradiography.

The aim of this paper is to describe an in vitro method which provides clear and accurate details of root canal shape. The method utilizes the technique of contact microradiography to produce high resolution, two-dimensional, real-size images of canals in a longitudinal plane. Specimens can be accurately rotated through 90 degrees allowing images to be produced in a bucco-lingual and mesio-distal direction. The method is simple, relatively rapid and can process large numbers of teeth without the need for complicated and expensive mounting blocks or film holders. The technique can be used to produce pre- and post-operative images of canal shape which can be superimposed to delineate the dentine removed during canal preparation. The method is thus suitable for the evaluation of the shaping ability of endodontic instruments and preparation techniques.

In vitro activities of antimicrobial agents against Proteus species from clinical specimens.

Two hundred clinical isolates of members of the genus Proteus were definitively identified and their antimicrobial susceptibilities to 12 antimicrobials tested, 176 isolates (88%) being identified as Proteus mirabilis, 12 strains (6%) as Proteus vulgaris and 12 strains (6%) as Proteus penneri. Most strains were isolated from pus (62.5%) and urine (34%), but in general there were no significant differences in the rates of isolation of any of the species by age or sex, although it was noted that P. vulgaris was only isolated from patients belonging to the older age group (> 5 years). The Proteus spp. were notably susceptible to nalidixic acid, ceftazidime and the aminoglycosides tested, and resistant to polymyxin B and colistin. The inclination of certain Proteus species to be susceptible or resistant to certain antimicrobials was noted, but strain differences also existed. The results of the study confirm the importance of performing antimicrobials susceptibility testing of each Proteus isolate to avoid potentially misleading therapy. The noted discrepancy in the result of the susceptibility of P. penneri to chloramphenicol as tested by different standard methods merits further investigation.