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21.
Clinical utility of EUS-guided fine-needle aspiration of mediastinal masses in the absence of known pulmonary malignancy 总被引:2,自引:0,他引:2
Devereaux BM Leblanc JK Yousif E Kesler K Brooks J Mathur P Sandler A Chappo J Lehman GA Sherman S Gress F Ciaccia D 《Gastrointestinal endoscopy》2002,56(3):397-401
BACKGROUND: Mediastinal masses represent a diagnostic challenge because of their proximity to numerous critical structures, difficulty of access for tissue sampling, and myriad potential pathologic etiologies. A large, single-center experience with EUS-guided fine-needle aspiration (EUS-FNA) in the diagnosis of non-lung cancer-related mediastinal masses is presented. METHODS: An EUS database was reviewed and all cases of mediastinal mass or lymphadenopathy encountered between 1994 and 1999 were included. Final diagnoses were determined by EUS-FNA cytology and clinical follow-up. RESULTS: Forty-nine patients were identified (27 women, 22 men; mean age 58.1 years, range 30-89 years). A malignant process was diagnosed in 22 cases (45%) and a benign process in 24 (49%). The EUS-FNA specimen was nondiagnostic in 3 cases (6%). An accurate diagnosis was made in 46 of the 49 patients (94%). No complication was noted. CONCLUSIONS: EUS-FNA is a minimally invasive technique that facilitates detection and tissue sampling of mediastinal masses. It is a safe procedure that can be performed with the patient under conscious sedation in an outpatient setting. 相似文献
22.
Sattar Alshryda James M. Mason Praveen Sarda T. Lou Martin Stanley Junjie Wu Anthony Unsworth 《Journal of orthopaedics and traumatology》2015,16(1):27-34
Background
Tranexamic acid (TXA) has been successfully used to reduce bleeding in joint replacement. Recently local TXA has been advocated to reduce blood loss in total knee or hip replacement; however, this raised concerns about potential adverse effects of TXA upon the artificial joint replacement.Materials and methods
In this biomechanical study we compared the effects of TXA and saline upon the following biomechanical properties of artificial joint materials—(1) tensile properties (ultimate strength, stiffness and Young’s modulus), (2) the wear rate using a multi-directional pin-on-plate machine, and (3) the surface topography of pins and plates before and after wear rate testing.Results
There were no significant differences in tensile strength, wear rates or surface topography of either ultra-high-molecular-weight polyethylene pins or cobalt chromium molybdenum metal plates between specimens soaked in TXA and specimens soaked in saline.Conclusion
Biomechanical testing shows that there are no biomechanical adverse affects on the properties of common artificial joint materials from using topical TXA.Level of evidence
V 相似文献23.
Sekar U Srikanth P Kindo AJ Babu VP Ramasubramanian V 《The Journal of communicable diseases》2003,35(3):162-169
Multidrug resistance among Salmonella typhi is well known. Reports of treatment failure in enteric fever with Ciprofloxacin made us undertake this study to determine the antibiotic susceptibility pattern of S. typhi and S. paratyphi A isolated from typhoid bacteremia cases, by disc diffusion and MIC by broth dilution method. A total of 50 strains were tested, 48 of Salmonella typhi and 2 of S. paratyphi A. The disc diffusion method was done using ampicillin, chloramphenicol, cotrimoxazole, tetracycline, ciprofloxacin, ofloxacin, cefuroxime and ceftriaxone as antibiotics. The MIC was performed using ciproloxacin, ofloxacin and ceftriaxone based on standard procedure. ACCOT resistance as determined by disc diffusion method was seen in 68% of isolates. All the strains remained susceptible to flouroquinolones cephalosporins and aminoglycosides. The MIC of ciprofloxacin, ofloxacin and ceftriaxone were in the recommended range of susceptibility as given by NCCLS, 14 (28%) strains had MIC of ciprofloxacin greater than 0.5 ug/ml with 4 strains having an MIC of 1.56 ug/ml; 25 (50%) strains had MIC of ofloxacin greater than 0.5 ug/ml and 20 (40%) strains had MIC of ceftriaxone greater than 0.5 ug/ml. The high levels of MIC of ciprofloxacin may account for treatment failure cases. The rising levels of MIC of ofloxacin and ceftriaxone in S. typhi and S. paratyphi is also of concern. We document here the emergence of high levels of MIC not only to ciprofloxacin, but also ofloxacin and ceftriaxone in S. typhi and S. paratyphi A. We recommend that MIC levels of ofloxacin and ceftriaxone should be monitored along with ciprofloxacin in treatment failure cases of enteric fever. 相似文献
24.
Durga Praveen Meka Anne Kathrin Müller-Rischart Prakash Nidadavolu Behnam Mohammadi Elisa Motori Srinivas Kumar Ponna Helia Aboutalebi Mahmoud Bassal Anil Annamneedi Barbara Finckh Margit Miesbauer Natalie Rotermund Christian Lohr J?rg Tatzelt Konstanze F. Winklhofer Edgar R. Kramer 《The Journal of clinical investigation》2015,125(5):1873-1885
Parkin and the glial cell line–derived neurotrophic factor (GDNF) receptor RET have both been independently linked to the dopaminergic neuron degeneration that underlies Parkinson’s disease (PD). In the present study, we demonstrate that there is genetic crosstalk between parkin and the receptor tyrosine kinase RET in two different mouse models of PD. Mice lacking both parkin and RET exhibited accelerated dopaminergic cell and axonal loss compared with parkin-deficient animals, which showed none, and RET-deficient mice, in which we found moderate degeneration. Transgenic expression of parkin protected the dopaminergic systems of aged RET-deficient mice. Downregulation of either parkin or RET in neuronal cells impaired mitochondrial function and morphology. Parkin expression restored mitochondrial function in GDNF/RET-deficient cells, while GDNF stimulation rescued mitochondrial defects in parkin-deficient cells. In both cases, improved mitochondrial function was the result of activation of the prosurvival NF-κB pathway, which was mediated by RET through the phosphoinositide-3-kinase (PI3K) pathway. Taken together, these observations indicate that parkin and the RET signaling cascade converge to control mitochondrial integrity and thereby properly maintain substantia nigra pars compacta dopaminergic neurons and their innervation in the striatum. The demonstration of crosstalk between parkin and RET highlights the interplay in the protein network that is altered in PD and suggests potential therapeutic targets and strategies to treat PD. 相似文献
25.
Prashant Pandey Divya Setya Vijay Sinha Anil Bhatt Amit Devra Amit Pande Praveen Kumar Shweta Ranjan 《Therapeutic apheresis and dialysis : official peer-reviewed journal of the International Society for Apheresis, the Japanese Society for Apheresis, the Japanese Society for Dialysis Therapy》2020,24(5):578-590
Successful renal transplantation across HLA barrier in sensitized individuals has been on the rise during the past decade, primarily due to improved desensitization regimes. The aim of this study was to share outcome of desensitization in renal transplant recipients with donor‐specific anti‐HLA antibodies (DSA). This was a retrospective analysis of all HLA immunized individuals who were prospective renal transplant recipients. All such patients underwent preconditioning as per the institutional desensitization protocol. Complement‐dependent cytoxicity‐based crossmatch (CDC‐XM), luminex‐based crossmatch (LM‐XM) and flowcytometry‐based crossmatch (FC‐XM) were done in all cases. If any of these tests turned out positive, single antigen bead assay (SAB) was performed. Desensitization for DSA was performed in 55 patients and all patients were followed‐up for 1 year to assess graft function and patient outcome. CDC‐XM being a less sensitive assay, could not detect incompatibility in 29 (52.73%) cases. After desensitization, even though SAB and LM‐XM results revealed an MFI within acceptable range, FC‐XM being an extremely sensitive assay, continued to give a positive result in eight (14.55%) cases. The mean ± SD number of pretransplant TPE were 3.44 ± 0.98 (2‐11). Out of 55, there were 10 patients who were lost to follow up. Patient and graft survival of 45 patients at 1 year was found to be 100%. Preconditioning for renal transplants in the form of immunosuppression with TPE is an extremely useful auxiliary for transplantation in HLA sensitized renal transplant recipients. 相似文献
26.
Xuchen Zhang Peiying Shan Robert Homer Yi Zhang Irina Petrache Praveen Mannam Patty J. Lee 《The American journal of pathology》2014,184(10):2730-2741
Emphysema is characterized by loss of lung elasticity and irreversible air space enlargement, usually in the later decades of life. The molecular mechanisms of emphysema remain poorly defined. We identified a role for a novel cathepsin, cathepsin E, in promoting emphysema by inducing mitochondrial fission. Unlike previously reported cysteine cathepsins, which have been implicated in cigarette smoke-induced lung disease, cathepsin E is a nonlysosomal intracellular aspartic protease whose function has been described only in antigen processing. We examined lung tissue sections of persons with chronic obstructive pulmonary disease, a clinical entity that includes emphysematous change. Human chronic obstructive pulmonary disease lungs had markedly increased cathepsin E protein in the lung epithelium. We generated lung epithelial-targeted transgenic cathepsin E mice and found that they develop emphysema. Overexpression of cathepsin E resulted in increased E3 ubiquitin ligase parkin, mitochondrial fission protein dynamin-related protein 1, caspase activation/apoptosis, and ultimately loss of lung parenchyma resembling emphysema. Inhibiting dynamin-related protein 1, using a small molecule inhibitor in vitro or in vivo, inhibited cathepsin E-induced apoptosis and emphysema. To the best of our knowledge, our study is the first to identify links between cathepsin E, mitochondrial fission, and caspase activation/apoptosis in the pathogenesis of pulmonary emphysema. Our data expand the current understanding of molecular mechanisms of emphysema development and may provide new therapeutic targets.Emphysema is a major subset of chronic obstructive pulmonary disease (COPD) and is defined anatomically as the destruction of the distal lung parenchyma and enlargement of the air spaces. Pulmonary emphysema is one of the main causes of morbidity and death worldwide. The most studied factor in developing COPD has long been recognized to be cigarette smoking. However, only 10% to 20% of heavy smokers develop clinically significant COPD.1,2 Importantly, recent studies indicate that complementary pathogenic mechanisms, such as proteolytic/antiproteolytic imbalance, oxidative stress, apoptosis, or altered innate immunity, are involved in the development and progression of alveolar destruction.3–6Cathepsins have been implicated in mediating alveolar destruction via their proteolytic activity. Cathepsins are intracellular hydrolases and include serine proteases (cathepsins A and G), aspartic proteases (cathepsins D and E), and cysteine cathepsins (cathepsins B, C, F, H, K, L, O, S, V, X, and W). Cathepsin E (Cat E), a nonlysosomal intracellular aspartic protease, is homologous to aspartic protease cathepsin D, a major proteolytic activity in the lysosomal component.7 Recent studies have reported that Cat E plays an important role in antigen processing via the major histocompatibility complex class II pathway, host defense against cancer cells and invading microorganisms, gastric differentiation, and development of signet-ring cell carcinoma.8–12 However, Cat E has not been linked to lung disease.Human lung sections from persons with COPD indicated increased expression of Cat E protein in the lung epithelial cells. To investigate if increased expression of lung epithelial Cat E could lead to emphysema, we generated lung-targeted constitutive and inducible Cat E transgenic (Tg) mice. Our data indicated that inducible Cat E Tg mice developed emphysema-like lung changes as early as 1 week. We noted robust caspase 3 activation, and, when mice were administered a caspase inhibitor, emphysema was prevented. To our surprise, we did not find changes in caspases usually associated with caspase 3 activation, such as caspases 8 and 9, in Cat E Tg mice. Instead, we found significant induction of a mitochondrial fission protein, dynamin-related protein 1 (Drp1). When we inhibited Drp1 in Cat E Tg mice with Mdivi-1, a small molecule Drp1 inhibitor, we completely abolished the development of emphysema. Collectively, our data indicate that increased Cat E is a clinically relevant finding in human COPD and invoke a novel role for Cat E in mitochondrial fission-induced emphysema. 相似文献
27.
Vineetha Raghavan Bhavneet Bharti Praveen Kumar Kanya Mukhopadhyay Lakhbir Dhaliwal 《Indian journal of pediatrics》2014,81(8):743-750
Objective
To assess the prevalence of first hour breastfeeding initiation and exclusive breastfeeding at 6 wk and identify its barriers in healthy term babies born in a tertiary hospital setting.Methods
A prospective observational cohort study was carried out in consecutively selected 400 mothers who delivered (normal, instrumental or cesarean) term healthy babies in a tertiary care hospital setting. All mother-infant dyads were enroled within 48 h of delivery.Results
Breastfeeding was initiated within first hour in 255 out of 400, i.e., 64 % of babies. Cesarean delivery and male gender were strongest risk factors for delayed initiation of breastfeeding [OR (95 % CI)?=?1.99 (1.14–3.48) and 34.17 (17.10–70.40) respectively]. Among the babies followed up till 6–8 wk, 83 % were exclusively breastfed. Breast milk substitutes were given in 172/400 (43 %) babies on day one, which emerged as an independent predictor of failure to continue exclusive breastfeeding at 6 wk (OR 2.96; 95 % CI 1.09–8.06). Odds of exclusive breastfeeding were two times higher in babies breastfed within first hour (n?=?255/400, 64 %) when compared to babies initiated breastfeeds beyond first hour (n?=?145/400, 36 %) (OR 2.01;05 % CI 1.12–3.61).Conclusions
Cesarean section and male gender emerged as significant risk factors for delayed initiation (beyond first hour) of breastfeeding in the index study cohort. In addition, use of breast milk substitute emerged as the only predictor for failure to continue exclusive breastfeeding at six weeks in a tertiary care hospital. 相似文献28.
Pradeep Kumar Sharma Bhaskar Saikia Rachna Sharma Kumar Ankur Praveen Khilnani Vinay Kumar Aggarwal Hae Cheong 《Indian journal of pediatrics》2014,81(10):1095-1098
Bartter syndrome is a group of inherited, salt-losing tubulopathies presenting as hypokalemic metabolic alkalosis with normotensive hyperreninemia and hyperaldosteronism. Around 150 cases have been reported in literature till now. Mutations leading to salt losing tubulopathies are not routinely tested in Indian population. The authors have done the genetic analysis for the first time in the Bartter syndrome on two cases from India. First case was antenatal Bartter syndrome presenting with massive polyuria and hyperkalemia. Mutational analysis revealed compound heterozygous mutations in KCNJ1(ROMK) gene [p(Leu220Phe), p(Thr191Pro)]. Second case had a phenotypic presentation of classical Bartter syndrome however, genetic analysis revealed only heterozygous novel mutation in SLC12A gene p(Ala232Thr). Bartter syndrome is a clinical diagnosis and genetic analysis is recommended for prognostication and genetic counseling. 相似文献
29.
Praveen Kumar Nicole K. Yamada Janene H. Fuerch Louis P. Halamek 《Indian journal of pediatrics》2014,81(5):473-480
The Neonatal Resuscitation Program (NRP) consists of an algorithm and curriculum to train healthcare professionals to facilitate newborn infants’ transition to extrauterine life and to provide a standardized approach to the care of infants who require more invasive support and resuscitation. This review discusses the most recent update of the NRP algorithm and recommended guidelines for the care of newly born infants. Current challenges in training and assessment as well as the importance of ergonomics in the optimization of human performance are discussed. Finally, it is recommended that in order to ensure high-performing resuscitation teams, members should be selected and retained based on objective performance criteria and frequent participation in realistic simulated clinical scenarios. 相似文献
30.
Venkataseshan Sundaram Dineshkumar Chirla Nalinikant Panigrahy Praveen Kumar 《Indian journal of pediatrics》2014,81(11):1198-1204
The number of Neonatal Intensive Care Units (NICUs) and Special Care Newborn Units (SCNUs) in the country has increased exponentially. However, their current status of functioning is not known. A structured questionnaire survey of 70 NICUs spread across the country was conducted to assess their infrastructure, staffing, equipment, patient profile and their involvement in research and training. Majority of the units were well staffed and led by neonatologists trained in India and abroad. All had facilities for mechanical ventilation and were equipped with sophisticated imported equipment. Yet, availability of in-house blood gas and X-ray, microbiology facility, invasive blood pressure monitoring and support of ophthalmologist was not universal. More than half had published papers in scientific journals and were having recognized training programs in neonatology. Though tremendous progress is visible since the last surveys, the number of NICUs is still grossly insufficient. The current and future gap in trained manpower is however daunting, and intensive efforts for expanding the in-service training programs and innovative approaches to training are required. There is an urgent need to improve the quality of care by launching collaborative quality improvement programsand mandatory periodicaccreditation managed by independent empowered organizations. The focus has to move forward from simply ‘survival till discharge’ to ‘intact complete life survival’. Simultaneously, the NICU care has to stay available and affordable for the masses. 相似文献