Assessment of P-Delta Effect on High Rise Buildings

P-delta effect is secondary effect on structure .it is also known as ‘Geometric nonlinearity effect’. As number of stories increases, P-delta effect becomes more important. If the change in bending moments and displacements is more than 10%, P-delta effect should be considered in design. In this study the P-delta effect on high rise building is studied. Linear static analysis (without P-delta effect) on high rise building having different number of stories is carried out. For the analysis G+14, G+19, G+24, (i.e 15, 20, and 25storey) R.C.C. framed building are modeled. Earthquake load is applied on model of structure as per IS-18939(2002) for zone III in E-Tab software. Load combination for analysis is set as per IS-456(2000).All analysis is carried out in software ETAB. Bending moment, story displacement with and without p-delta effect is calculated and compared for all the models. Then by trial and error method suitable cross-section are provided for unsafe building to bring within acceptable limit by increasing stiffness of a building. The result shows that it is essential to consider the P-delta effect for 25storey building. So buildings having height more than or equal to 75m, should be designed considering P-delta effect. Also we can say that up to 25storey building, it is not necessary to consider P-delta effect in design and primary or first order analysis is sufficient for design. By increasing stiffness of building by providing suitable cross section or by increasing stiffness building can bring within acceptable limit.[7] DOI: 10.17762/ijritcc2321-8169.150515

Peritoneal perfusion with oxygenated perfluorocarbon augments systemic oxygenation.

BACKGROUND: Despite maximal ventilatory support, many patients die from hypoxia in the setting of potentially reversible pulmonary failure. There remains a pressing need for additional pulmonary supportive care measures, especially techniques that do not require systemic anticoagulation. The objective of our experiments was to determine whether systemic oxygenation could be increased in a large animal, with induced hypoxia, by perfusing the abdominal cavity with oxygenated perfluorocarbons. METHODS: Fifteen pigs with a mean (+/- SD) weight of 45 +/- 5 kg were intubated and rendered hypoxic by ventilating them with a blend of nitrogen and oxygen to achieve subatmospheric concentrations of inspired oxygen ranging from 18 to 10%, resulting in baseline mean Pao(2) range of 65.9 +/- 9.7 to 26.6 +/- 2.8 mm Hg, respectively. Peritoneal perfusion was performed in eight animals with oxygenated perfluorocarbon and in seven control animals with oxygenated saline solution. RESULTS: The average increase in Pao(2) with oxygenated perfluorocarbon perfusion, compared to oxygenated saline solution perfusion, ranged from 8.1 to 18.2 mm Hg. A common treatment effect was estimated across all fraction of inspired oxygen (Fio(2)) values, representing the average mean difference in oxygen uptake between oxygenated perfluorocarbon and saline solution, irrespective of the level of Fio(2). This average was 12.8 mm Hg (95% confidence interval, 7.4 to 18.2; p \u3c 0.001). The most clinically relevant results occurred at an Fio(2) of 14%, resulting in a baseline mean Pao(2) of 39.4 +/- 5.0 mm Hg with oxygenated saline solution perfusion, and a mean Pao(2) of 55.3 +/- 7.6 mm Hg with oxygenated perfluorocarbon perfusion. This corresponded to an increase in arterial oxygen saturation from 73 to 89%. CONCLUSION: These results of our principle experiments demonstrate that the peritoneal cavity can be used for gas exchange and, in our model, yielded clinically relevant increases in systemic arterial oxygen levels. This technique may have the potential for the supportive care of patients dying from hypoxia in the setting of reversible lung injury

Fate of the lower extremity in patients with VA-ECMO via femoral cannulation

Background: Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is a salvage therapy in patients with severe cardiopulmonary failure. Femoral cannulation is associated with limb complications including ischemia, limb loss, arterial infections and wound infections. This study aims to evaluate these complications and management related to successful outcomes. Methods: A retrospective review was conducted in 17 patients requiring VA- ECMO support via femoral cannulation from 1/ 2010 till 4/2012. After cannulation, all patients had near infared spectroscopy (NIRS) monitoring after cannula placement and most had placement of distal arterial perfusion catheters (DPC). At decannulation, all patients had femoral cutdown with closure of arteriotomies by primary repair or patch angioplasty with bovine pericardium. Primary study endpoints included ischemia, limb loss, arterial infection; secondary endpoints were wound infection and post-discharge symptoms. Results: Seventeen patients were supported with VA-ECMO during the study period with arterial cannula size of 16-20 French. All patients had NIRS monitoring after cannula placement and 13/17 patients had DPC placement, with no subsequent ischemia. Two of 4 patients without DPC developed ischemia; one was decannulated and the other resolved spontaneously. At decannulation, open arterial repair was performed as described. In this study population, simple wound infection occurred in 3/17with Vacuum Assisted Closure (VAC) devices were placed at the timed if appropriate. There were no arterial infections and no instances of limb ischemia requiring amputation. There were no complaints of rest pain during outpatient follow-up. Conclusions: Limb complications related to femoral cannulation for VA-ECMO can lead to prolonged morbidity and limb loss. NIRS and placement of DPC, primary repair of arteriotomy or patch angioplasty, along with aggressive wound care, can dramatically decrease rates of limb ischemia, limb loss and infection

Incorporation of Whole Spine Screening in Magnetic Resonance Imaging Protocols for Low Back Pain: A Valuable Addition

Study DesignA retrospective review of lumbar magnetic resonance imaging (MRI) studies conducted at the Department of Radiodiagnosis & Imaging of a Tertiary Care Armed Forces Hospital between May 2014 and May 2016.PurposeTo assess the advantages of incorporating sagittal screening of the whole spine in protocols for conventional lumbar spine MRI for patients presenting with low back pain.Overview of LiteratureAdvances in MRI have resulted in faster examinations, particularly for patients with low back pain. The additional detection of incidental abnormalities on MRI helps to improve patient outcomes by providing a swifter definitive diagnosis. Because low back pain is extremely common, any change to the diagnostic and treatment approach has a significant impact on health care resources.MethodsWe documented all additional incidental findings detected on sagittal screenings of the spine that were of clinical significance and would otherwise have been undiagnosed.ResultsA total of 1,837 patients who met our inclusion criteria underwent MRI of the lumbar spine. The mean age of the study population was 45.7 years; 66.8% were men and 33.2% women. Approximately 26.7% of the patients were diagnosed with incidental findings. These included determining the level of indeterminate vertebrae, incidental findings of space-occupying lesions of the cervicothoracic spine, myelomalacic changes, and compression fractures at cervicothoracic levels.ConclusionsWe propose that T2-weighted sagittal screening of the whole spine be included as a routine sequence when imaging the lumbosacral spine for suspected degenerative pathology of the intervertebral discs

Does Intraoperative Radiation Therapy Improve Local Tumor Control in Patients Undergoing Pancreaticoduodenectomy for Pancreatic Adenocarcinoma? A Propensity Score Analysis

Background: Locoregional recurrence (LRR) is an important factor after pancreaticoduodenectomy (PD) for pancreatic cancer. IORT administered to the resection bed may improve local tumor control. Methods: We performed a retrospective analysis of patients who underwent PD at Thomas Jefferson University Hospital (TJUH) between 1995 and 2005 to identify patients who underwent resection with and without intraoperative radiation therapy (IORT). Data collected included age, gender, complications, margin status, stage, survival, and recurrence. Unadjusted analyses of the IORT and non-IORT groups were performed using Fisher’s chi-square method for discrete variables and Wilcoxon Rank Sum test for continuous variables. To account for biases in patient selection for IORT, a propensity score was calculated for each patient and adjusted statistical analyses were performed for survival and recurrence outcomes. Results: Between January 1995 and November 2005, 122 patients underwent PD for perimpullary tumors, including 99 pancreatic cancers. Of this group, 37 patients were treated with IORT, and there was adequate follow-up information for a group of 46 patients who underwent PD without IORT. The IORT group contained a higher percentage of Stage IIB or higher tumors (65%) than in the non-IORT group (39.1%), though differences in stage did not reach significance (p = 0.16). There was a non-significant decrease in the rate of LRR in patients who had IORT (39% non-IORT vs. 23% IORT, p = 0.19). The median survival time of patients who received IORT was 19.2 months, which was not significantly different than patients managed without IORT, 21.0 months (p=0.78). In the propensity analyses, IORT did not significantly influence survival or recurrence after PD. Conclusions: IORT can be safely added to management approaches for resectable pancreatic cancer, with acceptable morbidity and mortality. IORT did not improve loco-regional control and did not alter survival for patients with resected pancreatic cancer. IORT is an optional component of adjuvant chemoradiation for pancreatic cancer. In the future, IORT may be combined with novel therapeutic agents in the setting of a clinical trial in order to attempt to improve outcomes for patients with pancreatic cancer. Annals of Surgical Oncology, Volume 16, Edition 8, August, 2009, pages 2116-22, “Does intraoperative radiation therapy improve local tumor control in patients undergoing pancreaticoduodenectomy for pancreatic adenocarcinoma? A propensity score analysis”. Authors: Showalter TN, Rao AS, Anné PR, Rosato FE, Rosato EL, Andrel J, Hyslop T, Xu X, Berger AC

Single-stranded DNA binding protein from human malarial parasite Plasmodium falciparum is encoded in the nucleus and targeted to the apicoplast

Apicoplast, an essential organelle of human malaria parasite Plasmodium falciparum contains a ∼35 kb circular genome and is a possible target for therapy. Proteins required for the replication and maintenance of the apicoplast DNA are not clearly known. Here we report the presence of single–stranded DNA binding protein (SSB) in P falciparum. PfSSB is targeted to the apicoplast and it binds to apicoplast DNA. A strong ssDNA binding activity specific to SSB was also detected in P. falciparum lysate. Both the recombinant and endogenous proteins form tetramers and the homology modelling shows the presence of an oligosaccharide/oligonucleotide-binding fold responsible for ssDNA binding. Additionally, we used SSB as a tool to track the mechanism of delayed death phenomena shown by apicoplast targeted drugs ciprofloxacin and tetracycline. We find that the transport of PfSSB is severely affected during the second life cycle following drug treatment. Moreover, the translation of PfSSB protein and not the transcription of PfSSB seem to be down-regulated specifically during second life cycle although there is no considerable change in protein expression profile between drug-treated and untreated parasites. These results suggest dual control of translocation and translation of apicoplast targeted proteins behind the delayed death phenomena