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Background Protein-protein interaction (PPI) networks (interactomes) of most organisms, except for some model organisms, are largely unknown. Experimental methods including high-throughput techniques are highly resource intensive. Therefore, computational discovery of PPIs can accelerate biological discovery by presenting "most-promising" pairs of proteins that are likely to interact. For many bacteria, genome sequence, and thereby genomic context of proteomes, is readily available; additionally, for some of these proteomes, localization and functional annotations are also available, but interactomes are not available. We present here a method for rapid development of computational system to predict interactome of bacterial proteomes. While other studies have presented methods to transfer interologs across species, here, we propose transfer of computational models to benefit from cross-species annotations, thereby predicting many more novel interactions even in the absence of interologs. Mycobacterium tuberculosis (Mtb) and Clostridium difficile (CD) have been used to demonstrate the work. Results We developed a random forest classifier over features derived from Gene Ontology annotations and genetic context scores provided by STRING database for predicting Mtb and CD interactions independently. The Mtb classifier gave a precision of 94% and a recall of 23% on a held out test set. The Mtb model was then run on all the 8 million protein pairs of the Mtb proteome, resulting in 708 new interactions (at 94% expected precision) or 1,595 new interactions at 80% expected precision. The CD classifier gave a precision of 90% and a recall of 16% on a held out test set. The CD model was run on all the 8 million protein pairs of the CD proteome, resulting in 143 new interactions (at 90% expected precision) or 580 new interactions (at 80% expected precision). We also compared the overlap of predictions of our method with STRING database interactions for CD and Mtb and also with interactions identified recently by a bacterial 2-hybrid system for Mtb. To demonstrate the utility of transfer of computational models, we made use of the developed Mtb model and used it to predict CD protein-pairs. The cross species model thus developed yielded a precision of 88% at a recall of 8%. To demonstrate transfer of features from other organisms in the absence of feature-based and interaction-based information, we transferred missing feature values from Mtb orthologs into the CD data. In transferring this data from orthologs (not interologs), we showed that a large number of interactions can be predicted. Conclusions Rapid discovery of (partial) bacterial interactome can be made by using existing set of GO and STRING features associated with the organisms. We can make use of cross-species interactome development, when there are not even sufficient known interactions to develop a computational prediction system. Computational model of well-studied organism(s) can be employed to make the initial interactome prediction for the target organism. We have also demonstrated successfully, that annotations can be transferred from orthologs in well-studied organisms enabling accurate predictions for organisms with no annotations. These approaches can serve as building blocks to address the challenges associated with feature coverage, missing interactions towards rapid interactome discovery for bacterial organisms. Availability The predictions for all Mtb and CD proteins are made available at: http://severus.dbmi.pitt.edu/TB and http://severus.dbmi.pitt.edu/CD respectively for browsing as well as for download.

Bladder exstrophy is rare and associated with an increased incidence of bladder cancer. Unreconstructed bladder extrophy presenting in an adult is very rare as most of the patients undergo repair in childhood. Most of the cancers are adenocarcinomas. We report a rare case of squamous cell carcinoma occurring in exstrophic unreconstructed bladder in a 58-year-old male patient.

Endoscopic incision is a good management option for orthotopic ureterocele. But most of the literature has shown its efficacy only in children. We have done this retrospective study to evaluate the safety and efficacy of endoscopic incision of orthotopic ureterocele in adults. From March 2004 to January 2008, at our center, 26 adults underwent transurethral, transverse incision of an ureterocele. The perioperative data of these patients were retrospectively analyzed. The literature was reviewed to identify all the reported options for management of this relatively rare condition in adults. Unilateral ureterocele was present in 24 patients and two patients had bilateral ureterocele. One patient had associated upper tract stones. Three patients had associated stones in ureterocele. Transurethral, transverse incision of ureterocele was given in all patients. The mean postoperative hospital stay was 50.5 h. Twenty-three patients were available for follow-up at three, six and 12 months. All patients were symptom free. At three months ultrasound and intravenous urography revealed no residual ureterocele but four patients showed residual hydronephrosis, but with a decrease in the grade indicating decompression. Micturating cystourethrography revealed vesico-ureteral reflux (VUR) in two patients and the reflux persisted in one patient even at 6 months. We conclude that in adults, management with endoscopic incision of orthotopic ureterocele is safe and effective. VUR may occur in a few cases.

This paper presents our experience using the Unified Incident Command Decision Support System (UICDS) middleware platform developed by the U.S. Department of Homeland Security to facilitate sharing data between our Real-Time Decision Support System (RTDSS) and third party data sources. We describe the basics of UICDS and further show how we integrated UICDS one of our projects.

We present a low power probabilistic floating point multiplier. Probabilistic computation has been shown to be a technique for achieving energy efficient designs. As best known to the authors, this is the first attempt to use probabilistic digital logic to attain low power in a floating point multiplier. To validate the approach, probabilistic multiplications are introduced in a ray tracing algorithm used in computer graphics applications. It is then shown that energy savings of around 31% can be achieved in a ray tracing algorithm's floating point multipliers with negligible degradation in the perceptual quality of the generated image.

This study determines the biomechanical advantage and the optimal configuration of a high tibial osteotomy (HTO) and meniscus transplantation performed concurrently. Six cadaver knees were placed in a spatial frame, and an HTO was completed. Loading points between a mechanical 6 degrees of varus and 8 degrees ofvalgus were loaded to 800 N for medial meniscal intact, meniscectomized, and transplanted states. Posterior slope was also increased by 3 degrees in these specimens. Contact data was recorded. Peak pressures significantly increased in the meniscectomized state in every degree of varus/valgus (p < 0.05). For both peak and total medial compartment pressures, there was a significant drop (p < 0.001) between neutral and 3 degrees of valgus. Lateral compartment pressures linearly increased from varus to valgus orientation. There was no significant change in the pressure profile of the knee with a 3-degree increase in posterior slope. This biomechanical study confirms the hypothesis that an HTO improves the peak pressures in the medial compartment at all degrees of varus/valgus alignment in the setting of meniscal transplantation. Furthermore, the largest decrease in medial pressures was between neutral and 3 degrees of valgus, suggesting that perhaps neutral aligned knees could benefit from an HTO.

Background: Multiple bone-grafting procedures have been described for patients with glenoid bone loss and shoulder instability. The purpose of this study was to investigate the alterations in glenohumeral contact pressure associated with the placement and orientation of Latarjet or iliac crest bone graft augmentation and to compare the amount of glenoid bone reconstruction with two coracoid face orientations. Methods: Twelve fresh-frozen cadaver shoulders were tested in static positions of humeral abduction (30°, 60°, and 60° with 90° of external rotation) with a 440-N compressive load. Glenohumeral contact pressure and area were determined sequentially for (1) the intact glenoid; (2) a glenoid with an anterior bone defect involving 15% or 30% of the glenoid surface area; (3) a 30% glenoid defect treated with a Latarjet or iliac crest bone graft placed 2 mm proud, placed flush, or recessed 2 mm in relation to the level of the glenoid; and (4) a Latarjet bone block placed flush and oriented with either the lateral (Latarjet-LAT) or the inferior (Latarjet-INF) surface of the coracoid as the glenoid face. The amount of glenoid bone reconstructed was compared between the Latarjet-LAT and Latarjet-INF conditions. Results: Bone grafts in the flush position restored the mean peak contact pressure to 116% of normal when the iliac crest bone graft was used (p < 0.03 compared with the pressure with the 30% defect), 120% when the Latarjet-INF bone block was used (p < 0.03), and 137% when the Latarjet-LAT bone block was used (p < 0.04). Use of the Latarjet-LAT bone block resulted in mean peak pressures that were significantly higher than those associated with the iliac crest bone graft (p < 0.02) or the Latarjet-INF bone block (p < 0.03) at 60° of abduction and 90° of external rotation. With the bone grafts placed in a proud position, peak contact pressure increased to 250% of normal (p < 0.01) in the anteroinferior quadrant and there was a concomitant increase in the posterosuperior glenoid pressure to 200% of normal (p < 0.02), indicating a shift posteriorly. Peak contact pressures of bone grafts placed in a recessed position revealed high edge-loading. Augmentation with the Latarjet-LAT bone block led to restoration of the glenoid articular contact surface from the 30% defect state to a 5% defect state. Augmentation of the 30% glenoid defect with the Latarjet-INF bone block resulted in complete restoration to the intact glenoid articular surface area. Conclusions: Glenohumeral contact pressure is optimally restored with a flush iliac crest bone graft or with a flush Latarjet bone block with the inferior aspect of the coracoid becoming the glenoid surface. Bone grafts placed in a proud position not only increase the peak pressure anteroinferiorly, but also shift the articular contact pressure to the posterosuperior quadrant. Glenoid bone augmentation with a Latarjet bone block with the inferior aspect of the coracoid as the glenoid surface resulted in complete restoration of the 30% anterior glenoid defect to the intact state. These findings indicate the clinical utility of a flush iliac crest bone graft and utilization of the inferior surface of the coracoid as the glenoid face for glenoid bone augmentation with a Latarjet graft.

Decimal data processing applications have grown exponentially in recent years thereby increasing the need to have hardware support for decimal arithmetic. Binary to BCD conversion forms the basic building block of decimal digit multipliers. This paper presents novel high speed low power architecture for fixed bit binary to BCD conversion which is at least 28% better in terms of power-delay product than the existing designs.

BackgroundIn sum, 1-, 2-, and 4-stranded allografts are used for soft tissue anterior cruciate ligament reconstruction; however, the fixation properties of fixation devices are not well assessed.HypothesisThere are no differences in the biomechanical characteristics of 1 (Achilles)-, 2 (posterior tibialis)-, and 4 (semitendinosus)-stranded allograft tibial fixation.Study DesignControlled laboratory study.MethodsSixty-three fresh-frozen porcine tibiae were used to evaluate the fixation of 1-, 2-, and 4-stranded human tendon allografts (Achilles, posterior tibialis, and semitendinosus) with 3 fixation devices (Delta, Intrafix, and Calaxo screws). With use of a materials testing system, each graft was subjected to 500 cycles of loading (50-250 N, 0.75 mm/sec) to determine displacement and cyclic stiffness, followed by a monotonic failure test (20 mm/min) to determine maximum load and pullout stiffness.ResultsFor each graft type, there were no significant biomechanical differences between fixation devices. However, the 1-stranded graft (Achilles) construct demonstrated significantly higher mean displacement (3.17 ± 1.62 mm), lower cyclical stiffness (156 ± 25 N/mm), lower load to failure (479 ± 87 N), and lower pullout stiffness (140 ± 28 N/mm). In comparison with the 2-stranded graft (posterior tibialis), the 4-stranded graft (semitendinosus) exhibited lower displacement (0.86 ± 0.44 to 1.12 ± 0.51 mm) and higher ultimate failure load (832 ± 255 to 656 ± 168 N). Numerous differences in fixation properties were noted when comparing a device to each of the 3 grafts.ConclusionThe 1-stranded allograft demonstrated inferior biomechanical tibial fixation properties when compared with 2 (posterior tibialis)- and 4 (semitendinosus)-stranded allograft constructs for all fixation devices tested.Clinical RelevanceThis study demonstrated that not all tibial fixation devices are designed to adequately accommodate different types of anterior cruciate ligament allografts. Biomechanical evidence suggests that caution is warranted when using an Achilles allograft fixated solely with an interference device.

Decimal data processing applications have grown exponentially in recent years thereby increasing the need to have hardware support for decimal arithmetic. In this paper, an improved architecture for efficient Binary Coded Decimal (BCD) addition/subtraction is presented that performs binary addition/subtraction without any extra hardware. The architecture works for both signed and unsigned numbers. The design is runtime reconfigurable and maximum utilization of the hardware is a feature of the architecture. Simulation results show that the proposed architecture is at least 32% better in terms of power-delay product than the existing designs.

Closed queuing networks (CQNs) are generally used to model CONWIP systems. An implicit assumption in the CQN model is that whenever the work-in-process (WIP) level goes below the set value, there is always a job waiting for the released kanban. In other words, there are an infinite number of jobs in the external queue and as a result the kanban never waits in the resource pool. Modelling the CONWIP under this unrealistic assumption tends to underestimate the true cycle time of the kanban (and the job). In this technical note, we represent a CONWIP as a semi-open queuing network (SOQN) in which the job waits in the external queue until a kanban is available or vice-versa. Using published data and numerical experiments, we point out a modelling flaw of CONWIP systems in the literature and also show that the SOQN approach is a more appropriate model for representing CONWIP systems.

Since its introduction in 1987, the technique of cholecystectomy has continued to undergo evolution. Surgeons have reduced the port size and number or both to achieve improvement in postoperative pain control, rapid return to activity and better cosmetic results. Therefore, this study was done to compare the standard 4 port laparoscopic cholecystectomy (LC) with the 3 port laparoscopic cholecystectomy using a 5 mm telescope instead of 10 mm telescope (mini laparoscopic cholecystectomy - MLC). Forty patients were randomised to each group. Mean operating time, intraoperative and postoperative complications, mean period to resume walking, eating and return to normal activities and mean hospital stay were similar in the two groups. The level of postoperative pain was significantly lower in the MLC group. Patients who underwent MLC required a significantly lower dose of analgesics. In conclusion mini laparoscopic cholecystectomy is a feasible and safe procedure with less postoperative pain and better cosmesis and without increased complications.

Acute appendicitis may simulate many other acute abdominal illnesses and the exact diagnosis is important for the proper management. The present study was undertaken to evaluate the role of the Alvarado score in the diagnosis of a patient with suspected appendicitis. The study was carried out on 100 patients operated with a presumptive diagnosis of acute appendicitis on the basis of clinical grounds. Alvarado scoring was done in all these patients preoperatively by different personnel. Discriminant analysis of the Alvarado score of all the patients was done to determine the cut-off value in an Indian set-up. The positive and negative predictive values of the Alvarado score were 77.6% and 52.4%, respectively. It is more effective in men and children, with a predictive value of 84% and 92.8%, respectively. Discriminant analysis revealed a cut-off value ofor = 6 rather than the original value ofor = 7. The sensitivity of the Alvarado score increased from 69.2% to 92% with the new cut-off value ofor =6. The Alvarado scoring system can be used in surgical emergency departments to diagnose acute appendicitis. In women, additional investigations may be required to confirm the diagnosis. The original cut-off value given by Alvarado may be changed in the Indian set-up to increase sensitivity.

Systemic lupus erythematosus (SLE) is an uncommon immunological disorder with multisystemic involvement. Neurological and neuropsychiatric manifestations in this disease are multifactorial and can involve any part of this system. We describe one patient presenting with spastic quadriparesis as an early clinical manifestation of SLE. This disease should be kept in mind in such a setting, especially if abnormalities in hemogram and urine analysis are seen. Early diagnosis and aggressive therapy may improve the neurological outcome.

Audiovestibular functions in 50 cases of diabetes mellitus have been evaluated to find out the type of hearing loss. Diabetes mellitus causes a significant bilateral symmetrical hearing loss at higher frequencies and with the progress of disease and added complications the hearing further deteriorates. On control of diabetes hearing changes are found to be irreversible. However vestibular functions remain uninvolved in cases of diabetes mellitus. A direct correlation was found between hearing loss and increasing blood sugar level.

Context and Aim: Prostatic abscess is an unusual condition. The prevalence of prostatic abscess is about 0.5% of all prostatic diseases. The purpose of the study is to present and discuss the role of transrectal ultrasound (TRUS) in the management of prostatic abscess. Settings and Design: Retrospective study. Materials and Methods: We retrospectively reviewed the medical records of all eight patients diagnosed and treated for prostatic abscess in the last threeyears. TRUS was used for diagnosis in all cases. Four patients had TRUS guided aspiration for management of prostatic abscess. Data collected regarding etiology, clinical features, investigations and treatment was compared with the available literature. Results: The age of patients ranged from 18-65 yrs (mean 47.12 yrs). Out of the eight patients, six were diabetics. TRUS revealed one or more hypoechoic areas within the prostate in all the patients. Successful treatment of prostatic abscess with TRUS guided needle aspiration was done in all fourpatients in whom it was used. Mean hospitalization time was 9.4 days, and most frequent bacterial agent was S. aureus. Conclusions: TRUS is useful in diagnosis as well as in guidance for aspiration of such abscesses. TRUS guided needle aspiration is an effective method for treating prostatic abscess. Most of the patients are diabetics and usually grow Staphaureus. So an antibiotic with staphylococcal coverage should be used empirically.

Aim: We assessed the results of laparoscopic transperitoneal ureteroneocystostomy with or without a psoas hitch for management of lower ureteral strictures. Materials and Methods: Between October 2005 and August 2008, 16 patients with lower ureteric strictures underwent laparoscopic ureteroneocystostomy with or without a psoas hitch. Etiology of strictures was gynecological surgery in 11, surgery for stone disease in 3, ureterovaginal fistula in 1 and primary obstructive megaureter in 1. Transperitoneal 3- or 4-port laparoscopic ureteroneocystostomy was performed with or without psoas hitch. Results: All operations were successfully completed without any need for conversion to open. Mean operative time was 171.56 min (range 130 to 260 min), mean blood loss was 93.44 cc (range 30 to 200 cc) and total hospital stay was 3.73 days (range 3 to 6 days). Mean time to resume oral intake was 12.5 h (range 8 to 22 h). Mean follow-up period was 21.83 months (range 6-39 months). Postoperative follow-up investigations revealed successful outcome in all 16 patients, success being defined as relief of symptoms and radiological improvement, irrespective of the refluxing status. Non-refluxing status was achieved in 15 out of 16 patients as determined by micturition cystography. Conclusions: Laparoscopic ureteroneocystostomy is a safe and effective procedure, with inherent advantages of laparoscopic surgery.

Cystic hygroma is a disfiguring benign lesion commonly observed in the neck and face regions of children. The common complications of these malformations are respiratory obstruction, dysphagia, infection, and hemorrhage. Here, we present an uncommon complication of spontaneous rupture of a cystic hygroma. A two-day-old male baby presented with a swelling that was cystic, non-compressible, non-pulsatile and the transillumination was negative. With a clinical diagnosis of a massive cystic hygroma of the neck, CT scan was performed that demonstrated a large multiloculated cystic lesion. On the second day after admission, the swelling burst spontaneously with drainage of about 1000 ml of hemorrhagic fluid. The swelling shrunk considerably after that. The patient underwent surgical excision of the lesion and had an uneventful postoperative recovery. The histopathological examination confirmed the diagnosis of cystic hygroma.

The genetic alterations and aberrant miRNA expression profiles have been identified as important events behind the emergence of cancer. This knowledge triggers the use of miRNA therapeutics as an anticancer strategy. Basically, MicroRNAs (miRNAs) are approximately 22-nucleotide long, endogenous non-protein-coding RNA molecules which function as important regulatory molecules that regulate gene and protein expression through the RNA interference (RNAi) machinery. Transcription of these molecules by RNA polymerases II and III, resulting in the generation of precursor microRNAs that undergo a series of cleavage events, consequently, generate the mature microRNA. The biogenesis pathway is mediated by the two important cleavage events such as nuclear and cytoplasmic. The regulatory functions of microRNAs are accomplished through the RNA-induced silencing complex (RISC), leading to translational repression and hence, regulate the gene expression. The current progress in the development of strategies for miRNA-based anticancer therapies is due to its involvement in cellular, developmental and biological processes including regulation in cancer cell and modulation by various cancer chemoprophylaxis agents. Although miRNA therapeutics have been found to suppress gene expression effectively as compared to anti-sense oligonucleotide strategies, but it is bound with some limitations viz. identification of tissue specific miRNA, biological instability, off-target effects and delivery in the cell system. Up to certain extent, these hurdles have been resolved by chemical modifications using cholesterol conjugation, morpholinos, cationic lipids and cationic nanoparticles. Still more research is needed to understand the mechanism of action for better miRNA therapeutics. The paper discusses the potential miRNA therapeutics and diagnostic applications for cancer prevention, based on recent patents and their analysis.