127 research outputs found
Case Histories of Soil Behaviour and Investigations for Seismically Distressed Earthen Dams of Kachchh Region in Gujarat, India
In the morning of January 26, 2001, a devastating earthquake of magnitude Mw 7.7 rocked the Gujarat State of India. The disastrous earthquake claimed thousands of human lives besides widespread destruction of the properties including damages to water resources projects of Kachchh region. This worst ever natural calamity of recent time posed challenging and daunting task of restoration and reconstruction works. A committee of experts was constituted by Government of Gujarat with a view to assess the damages occurred to the dams & other appurtenant structures and to recommend restoration and reconstruction works. Consequent to the event, dams of Kachchh region situated within radius of 200 km from the epicenter were inspected as per the guidelines of International Commission On Large Dams (ICOLD). Integrated geotechnical investigation program comprising soil exploration and laboratory testing was chalked out to determine the properties of foundation & embankment soils. The paper describes the seismic data on Bhuj Earthquake, geology of Kachchh region, geotechnical investigation including assessment of liquefaction potential and their considerations in the restoration measures of two earth dams
Macrophage migration inhibitory factor downregulation: a novel mechanism of resistance to anti-angiogenic therapy.
Anti-angiogenic therapies for cancer such as VEGF neutralizing antibody bevacizumab have limited durability. While mechanisms of resistance remain undefined, it is likely that acquired resistance to anti-angiogenic therapy will involve alterations of the tumor microenvironment. We confirmed increased tumor-associated macrophages in bevacizumab-resistant glioblastoma patient specimens and two novel glioblastoma xenograft models of bevacizumab resistance. Microarray analysis suggested downregulated macrophage migration inhibitory factor (MIF) to be the most pertinent mediator of increased macrophages. Bevacizumab-resistant patient glioblastomas and both novel xenograft models of resistance had less MIF than bevacizumab-naive tumors, and harbored more M2/protumoral macrophages that specifically localized to the tumor edge. Xenografts expressing MIF-shRNA grew more rapidly with greater angiogenesis and had macrophages localizing to the tumor edge which were more prevalent and proliferative, and displayed M2 polarization, whereas bevacizumab-resistant xenografts transduced to upregulate MIF exhibited the opposite changes. Bone marrow-derived macrophage were polarized to an M2 phenotype in the presence of condition-media derived from bevacizumab-resistant xenograft-derived cells, while recombinant MIF drove M1 polarization. Media from macrophages exposed to bevacizumab-resistant tumor cell conditioned media increased glioma cell proliferation compared with media from macrophages exposed to bevacizumab-responsive tumor cell media, suggesting that macrophage polarization in bevacizumab-resistant xenografts is the source of their aggressive biology and results from a secreted factor. Two mechanisms of bevacizumab-induced MIF reduction were identified: (1) bevacizumab bound MIF and blocked MIF-induced M1 polarization of macrophages; and (2) VEGF increased glioma MIF production in a VEGFR2-dependent manner, suggesting that bevacizumab-induced VEGF depletion would downregulate MIF. Site-directed biopsies revealed enriched MIF and VEGF at the enhancing edge in bevacizumab-naive patients. This MIF enrichment was lost in bevacizumab-resistant glioblastomas, driving a tumor edge M1-to-M2 transition. Thus, bevacizumab resistance is driven by reduced MIF at the tumor edge causing proliferative expansion of M2 macrophages, which in turn promotes tumor growth
Rectovaginal Fistulas Not Involving the Rectovaginal Septum Should Be Treated Like Anal Fistulas: A New Concept and Proposal for a Reclassification of Rectovaginal Fistulas
Pankaj Garg,1 Laxmikant Ladukar,2 Vipul D Yagnik,3 Kaushik Bhattacharya,4 Gurleen Kaur5 1Department of Colorectal Surgery, Garg Fistula Research Institute (GFRI), Panchkula, Haryana, India; 2Department of Surgery, Ladukar Surgical Hospital, Bramhapuri, Maharashtra, India; 3Department of Surgery, Banas Medical College and Research Institute, Palanpur, Gujarat, India; 4Department of Surgery, MGM Medical College and LSK Hospital, Kishanganj, Bihar, India; 5Department of Pharmacology, Adesh Medical College and Hospital, Shahbad, Haryana, IndiaCorrespondence: Pankaj Garg, Chief Colorectal Surgeon, Colorectal Surgery, Garg Fistula Research Institute (GFRI), 1042, Sector-15, Panchkula, Haryana, 134113, India, Email [email protected]: Many rectovaginal fistulas(RVF), especially low RVF, do not involve/penetrate the RV-septum, but due to lack of proper nomenclature, such fistulas are also managed like RVF (undertaking repair of RV-septum) and inadvertently lead to the formation of a high RVF (involving RV-septum) in many cases. Therefore, REctovaginal Fistulas, Not Involving the Rectovaginal Septum, should be Treated like Anal fistulas(RENISTA) to prevent any risk of injury to the RV septum. This concept(RENISTA) was tested in this study.Methods: RVFs not involving RV-septum were managed like anal fistulas, and the RV-septum was not cut/incised. MRI, objective incontinence scoring, and anal manometry were done preoperatively and postoperatively. High RVF (involving RV-septum) were excluded.Results: Twenty-seven patients with low RVF (not involving RV-septum) were operated like anal fistula[age:35.2± 9.2 years, median follow-up-15 months (3– 36 months)]. 19/27 were low fistula[ 1/3 EAS involved) and underwent a sphincter-sparing procedure. Three patients were excluded. The fistula healed well in 22/24 (91.7%) patients and did not heal in 2/24 (8.3%). The healing was confirmed on MRI, and there was no significant change in mean incontinence scores and anal pressures on tonometry. RV-septum injury did not occur in any patient.Conclusions: RVF not involving RV-septum were managed like anal fistulas with a high cure rate and no significant change in continence. RV-septum injury or formation of RVF with septum involvement did not occur in any patient. The RENISTA concept was validated in the present study. A new classification was developed to prevent any inadvertent injury to the RV-septum.Keywords: rectovaginal, fistula, anal, incontinence, recurrence, scoring system, fistulotomy, classificatio
An Analysis of Functional Status in Multiple Sclerosis Patients after Progressive Non-Aerobic High-Intensity Maximal Effort Exercise (MEE)
Background: Multiple Sclerosis (MS) is a disease with a wide-ranging impact on functional status. MS patient function has been assessed using Multiple Sclerosis Functional Composite Score (MSFCS). The MSFCS includes the standardized scores (Z-score) of three functional tests: the Paced Auditory Serial Addition Test (PASAT-3”) for cognitive function, 9-Hole Peg Test (9-HPT) for upper extremity function, and timed 25-foot walk (25-TW) for lower extremity function. One of the most common symptoms experienced by MS patients is severe fatigue, often brought on suddenly by aerobic exercise. Non-aerobic maximal effort exercise (MEE) is thought to increase strength without increasing fatigue. The IsoPUMP® (Neuromuscular Engineering; Nashville, TN) is a stationary exercise device designed for patient use to safely perform MEE leg presses and whole body lunges using isometric and eccentric exercises. The progressive functional changes of the MS patients were tracked using the MSFCs at specific intervals during the study
Effects of Non-Aerobic Maximal Effort Exercise on Fatigue in Deconditioned Men and Women with Multiple Sclerosis
Multiple Sclerosis (MS) is a neurodegenerative disease of unknown etiology affecting women more frequently than men. Mental and physical fatigue complaints are often the most disabling symptoms for an MS patient. Both are multifactorial, potentially exacerbated by aerobic exercise, may prevent sustained physical functioning, and significantly interfere with activities of daily living1. A multi-center study was designed to investigate the effects of non-aerobic maximal effort exercise (MEE) for deconditioned persons with MS, with the expectation of minimizing fatigue. The IsoPUMP (Neuromuscular Engineering; Nashville, TN), is a specialized exercise and strength-sensing machine, designed to allow individuals to safely perform and record their non-aerobic MEE sessions. The Modified Fatigue Impact Scale (MFIS) and Multiple Sclerosis Functional Composite (MSFC) are common, accepted methods used to measure fatigue and function. The MFIS is a 21-item questionnaire which assesses the subjects’ perception of physical, cognitive, and psychosocial aspects of fatigue over a four-week period2. Each of the 21 items are scored on a scale from 0 (never) to 4 (almost always), and the total MFIS score is calculated by summing the circled number for each item. Total scores can range from 0 to 84; higher scores indicating a greater impact of fatigue on the person. The MFIS has three distinct subscales: (1) physical, (2) cognitive, and (3) psychosocial. These subscales can be scored independently by summing the questions that pertain to each subscale2. The MFIS physical subscale score can range from 0 – 36 and the MFIS cognitive subscale score can range from 0 – 40. The MSFC combines clinical measures used to assess lower limb function (Timed 25-Foot Walk [25-FW]), upper limb function (9-Hole Peg Test [9-HPT]), and cognition (Paced Auditory Serial Addition Test [PASAT-3”])3. The 25-FW is a quantitative measure of lower extremity function. The 9-HPT is a quantitative measure of arm and hand function where a subject inserts and then removes 9 pegs from a board, using one hand at a time. The time is recorded for each hand with the dominant hand trial first and the non-dominant hand trial second. The final score is recorded as the mean time for both hands. The PASAT-3” is a measure of cognitive function, specifically assessing auditory information processing speed, short-term memory, flexibility, and calculation ability. Cognitive dysfunction affects half of all MS patients; slowing ability to reason, concentrate, and recall5. In this test subjects listen to a series of 61 spoken numbers separated by 3 seconds and must add each number to the prior number. Their final PASAT-3” score is the number of correct additions in the series, with 60 reflecting a perfect score. The MSFC is then evaluated by creating Z-scores for each component, which compare each outcome with the average outcome of the study population. The three Z-scores are then averaged to create an overall composite score (the MSFC score) which represents change over time for that population of MS subjects3
The Effect of Progressive Non-Aerobic High-Intensity Maximal Effort Exercise (MEE) on the Health-Related Quality of Life in Patients with Multiple Sclerosis
Background: Studies indicate that Multiple Sclerosis (MS) patients are less satisfied with the quality of their lives than healthy individuals in similar circumstances. Common symptoms experienced include fatigue, cognitive dysfunction, pain, spasticity, depression, bladder/bowel dysfunction and sexual dysfunction. Several pharmacological and non-pharmacological methods have been employed for such symptoms to try to increase quality of life and reduce the mortality rate. Non-pharmacological methods recommended for MS patients include lifestyle modifications, exercise programs and physical therapy. MS patients easily fatigue during aerobic exercise but a non-aerobic progressive maximal effort exercise (MEE) protocol consisting of a few short, duration isometric and eccentric leg press and whole body lunges was previously seen to increase strength without increasing fatigue. The IsoPUMP® (Neuromuscular Engineering, Nashville TN) exercise system permitted safe conduct and measurement of muscle strength and duration during each exercise repetition
A Comparison of Four Treatments for Generalized Convulsive Status Epilepticus
ABSTRACT
Background and Methods Although generalized convulsive status epilepticus is a life-threatening emergency, the best initial drug treatment is uncertain. We conducted a five-year randomized, doubleblind, multicenter trial of four intravenous regimens: diazepam (0.15 mg per kilogram of body weight) followed by phenytoin (18 mg per kilogram), lorazepam (0.1 mg per kilogram), phenobarbital (15 mg per kilogram), and phenytoin (18 mg per kilogram). Patients were classified as having either overt generalized status epilepticus (defined as easily visible generalized convulsions) or subtle status epilepticus (indicated by coma and ictal discharges on the electroencephalogram, with or without subtle convulsive movements such as rhythmic muscle twitches or tonic eye deviation). Treatment was considered successful when all motor and electroencephalographic seizure activity ceased within 20 minutes after the beginning of the drug infusion and there was no return of seizure activity during the next 40 minutes. Analyses were performed with data on only the 518 patients with verified generalized convulsive status epilepticus as well as with data on all 570 patients who were enrolled.
Results Three hundred eighty-four patients had a verified diagnosis of overt generalized convulsive status epilepticus. In this group, lorazepam was successful in 64.9 percent of those assigned to receive it, phenobarbital in 58.2 percent, diazepam and phenytoin in 55.8 percent, and phenytoin in 43.6 percent (P=0.02 for the overall comparison among the four groups). Lorazepam was significantly superior to phenytoin in a pairwise comparison (P=0.002). Among the 134 patients with a verified diagnosis of subtle generalized convulsive status epilepticus, no significant differences among the treatments were detected (range of success rates, 7.7 to 24.2 percent). In an intention-to-treat analysis, the differences among treatment groups were not significant, either among the patients with overt status epilepticus (P=0.12) or among those with subtle status epilepticus (P=0.91). There were no differences among the treatments with respect to recurrence during the 12- hour study period, the incidence of adverse reactions, or the outcome at 30 days.
Conclusions As initial intravenous treatment for overt generalized convulsive status epilepticus, lorazepam is more effective than phenytoin. Although lorazepam is no more efficacious than phenobarbital or diazepam and phenytoin, it is easier to use. (N Engl J Med 1998;339:792-8.
Experimental study of PLA thermal behavior during fused filament fabrication
Fused filament fabrication (FFF) is an additive manufacturing technique that is used to produce prototypes and a gradually more important processing route to obtain final products. Due to the layer-by-layer deposition mechanism involved, bonding between adjacent layers is controlled by the thermal energy of the material being printed, which strongly depends on the temperature development of the filaments during the deposition sequence. This study reports experimental measurements of filament temperature during deposition. These temperature profiles were compared to the predictions made by a previously developed model. The two sets of data showed good agreement, particularly concerning the occurrence of reheating peaks when new filaments are deposited onto previously deposited ones. The developed experimental technique is shown to demonstrate its sensitivity to changing operating conditions, namely platform temperature and deposition velocity. The data generated can be valuable to predict more accurately the bond quality achieved in FFF parts
Structural Basis for Broad Neutralization of Hepatitis C Virus Quasispecies
Monoclonal antibodies directed against hepatitis C virus (HCV) E2 protein can neutralize cell-cultured HCV and pseudoparticles expressing envelopes derived from multiple HCV subtypes. For example, based on antibody blocking experiments and alanine scanning mutagenesis, it was proposed that the AR3B monoclonal antibody recognized a discontinuous conformational epitope comprised of amino acid residues 396–424, 436–447, and 523–540 of HCV E2 envelope protein. Intriguingly, one of these segments (436–447) overlapped with hypervariable region 3 (HVR3), a domain that exhibited significant intrahost and interhost genetic diversity. To reconcile these observations, amino-acid sequence variability was examined and homology-based structural modelling of E2 based on tick-borne encephalitis virus (TBEV) E protein was performed based on 413 HCV sequences derived from 18 subjects with chronic hepatitis C. Here we report that despite a high degree of amino-acid sequence variability, the three-dimensional structure of E2 is remarkably conserved, suggesting broad recognition of structural determinants rather than specific residues. Regions 396–424 and 523–540 were largely exposed and in close spatial proximity at the surface of E2. In contrast, region 436–447, which overlaps with HVR3, was >35 Å away, and estimates of buried surface were inconsistent with HVR3 being part of the AR3B binding interface. High-throughput structural analysis of HCV quasispecies could facilitate the development of novel vaccines that target conserved structural features of HCV envelope and elicit neutralizing antibody responses that are less vulnerable to viral escape
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