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1.
Joshua Manghelli Lisa Brown Hany B. Tadros Nabil A. Munfakh 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》2015,42(5):491-494
The inflammatory response induced by cardiopulmonary bypass decreases vascular tone, which in turn can lead to vasoplegic syndrome. Indeed the hypotension consequent to on-pump cardiac surgery often necessitates vasopressor and intravenous fluid support. Methylene blue counteracts vasoplegic syndrome by inhibiting the formation of nitric oxide.We report the use of methylene blue in a 75-year-old man who developed vasoplegic syndrome after cardiac surgery. After the administration of methylene blue, his hypotension improved to the extent that he could be weaned from vasopressors. The use of methylene blue should be considered in patients who develop hypotension refractory to standard treatment after cardiac surgery. 相似文献
2.
Phyllis W Sharps Ayman A E El-Mohandes M Nabil El-Khorazaty Michele Kiely Tessa Walker 《Journal of perinatology》2003,23(5):414-419
OBJECTIVE: To describe breastfeeding initiation among 210 urban African-American mothers with inadequate prenatal care. METHODS: This study is a case-control study of postpartum mothers recruited from four large urban hospitals. RESULTS: Mothers who chose to breastfeed were more educated, employed before birth, married, and using contraception postnatally. Regression model analysis controlling for demographic differences revealed that breastfeeding was significantly associated with a higher perception of severity of illness and higher confidence in the ability of health care to prevent illness. Breastfeeding mothers were less likely to reverse parent-child roles and had a lower perception of hassle from their infant's behavior. When comparing mothers who breastfed longer than 8 weeks to those who did not breastfeed, breastfeeding mothers had high scores related to empathy toward infants on the Adult-Adolescent Parenting Inventory as well as a low perception of hassle on the Parenting Daily Hassle. The perception of existing formal or informal social support did not influence breastfeeding behavior. CONCLUSION: Personal attributes of low-income urban mothers such as health beliefs and parental attitudes may play a role in the initiation and duration of breastfeeding. Low-income African-American mothers may be influenced in their choice to breastfeed by supportive messages from physicians and nurses delivering care to mothers and their newborns. Emphasis should be placed on the role breastfeeding can play in preventing childhood illnesses. 相似文献
3.
Nabil El-Sherif 《The International Journal of Cardiac Imaging》1991,7(3-4):141-150
In this work the electrophysiologic mechanisms of ventricular arrhythmias have been briefly summarized. Ventricular arrhytmias can be caused either by pacemaker activity or by reentrant excitation. Enhancement of normal automaticy can generate a parasystolic rhythm in normal fibers. Abnormal automaticity may arise fom fibers in which maximum diastolic potential has been reduced by a variety of interventions. Triggered activity is caused by either an early (EAD) or delayed (DAD) afterdepolarization and requires a prior normal action potential for initiation. While there is growing evidence that EAD-induced triggered activity plays a significant role in the Long QTU syndrome and Torsade de Pointes, no clinical arrhythmias has definitely been ascribed to DADs, although DADs have been recorded in man after acute digoxin intoxication.Ventricular arrhytmias can be also caused by reentrant excitation, which can be subdivided into reflection or circus movement reentry (CMR). In the reflection model impulses in both directions are transmitted over the same pathway. In the CMR three models can be differentiated: the ring model, which requires a fixed anatomical obstacle; the figure-eight model and the leading circle model, where functional rather than fixed anatomical obstacles are involved.Abbreviations AV
atrio-ventricular
- CMR
circus movement reentry
- DAD
delayed afterdepolarization
- EAD
early afterdepolarization
- ECG
electrocardiogram
- LV
left ventricle
- MAP
monophasic action potential
- MF
muscle fiber
- PF
Purkinje fiber
- RV
right ventricle
- TdP
Torsade de Pointes 相似文献
4.
Concomitant administration of cyclosporine and ketoconazole in idiopathic nephrotic syndrome. 总被引:1,自引:1,他引:0
Amr El-Husseini Fathy El-Basuony Ahmed Donia Ihab Mahmoud Nabil Hassan Nagy Sayed-Ahmad Mohamed Sobh 《Nephrology, dialysis, transplantation》2004,19(9):2266-2271
BACKGROUND: The deliberate use of ketoconazole to reduce the need for cyclosporine (CsA) is not new, but it is particularly relevant because of the high cost of CsA. Many studies have documented this benefit in renal and cardiac transplants, but this co-administration has not been reported in patients with nephrotic syndrome. METHODS: This retrospective study included 207 nephrotic patients who were steroid resistant, dependent or frequent relapsers and received CsA therapy. Among these patients 153 received daily ketoconazole therapy in a dose of 50 mg with concomitant decrease of one-third of the CsA dose while 54 patients received CsA alone. The majority of our cases were children (179 were below 18 years) and male to female ratio was 1.7:1. RESULTS: The great majority of the study population received the drugs for 1-2 years. Patients who received CsA and ketoconazole were comparable with those who received CsA alone regarding age, sex, duration of renal disease, renal pathology, severity of nephrotic syndrome, renal function, hepatic function and steroid response. Co-administration of ketoconazole significantly reduced mean doses of CsA by 37% after 1 month and 47% at 1 year with overall net cost savings of 37%. Hepatic functions remained within the normal range in both groups. Additionally, co-administration of ketoconazole significantly improved the response to CsA therapy, successful steroid withdrawal and decreased the frequency of renal impairment. CONCLUSIONS: Co-administration of keto with CsA in idiopathic nephrotic patients significantly reduces CsA costs and may improve its response. 相似文献
5.
Abdul Rahman Arishi M. Ezzedien Rabie M. Shahid Hussain Khan Hassan Sumaili Hassan Shaabi Nabil Tadros Michael Bheem Sing Shekhawat 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2008,12(3):321-325
Spillage of gallstones may occur in the course of laparoscopic cholecystectomy. The incidence of this mishap and its consequences are variable. Ignored by many surgeons, stone spillage may be the source of significant morbidity many years after surgery. In this report, we describe the clinical course of a patient who presented with upper abdominal pain and swelling. The past history was positive for laparoscopic cholecystectomy 15 years earlier. After excision, the swelling was found to be a pseudocyst formed around spilled gallstones during a previous cholecystectomy. Apart from postoperative wound infection, the patient recovered well and remains so. Here, we discuss the problem and provide suggestions for spillage prevention and stone retrieval once spillage occurs. 相似文献
6.
Nabil Nakhostine Daniel Lamontagne 《Pflügers Archiv : European journal of physiology》1994,428(5-6):526-532
The mechanism of hypoxia-induced coronary vasodilatation was studied in isolated, saline-perfused rabbit hearts under constant flow conditions. Reduction in the perfusion solution PO2 (from 520±6 to 103±9 mm Hg) under control conditions halved the coronary resistance and was accompanied by a significant release of the prostaglandin (PG) 6-keto-PGF1 (from 1.8±0.3 to a maximum of 4.4±0.9 pmol min–1 g–1). The cyclooxygenase inhibitor, diclofenac (1 M), blocked the release of PGI2 and reduced hypoxia-induced vasodilatation (from 47±8% to 25±5%, P<0.05). The relative contribution of adenosine, prostaglandins, and adenosine triphosphate (ATP)-sensitive K+ channel (KATP channel) activation in hypoxia-induced vasodilatation was assessed by comparing the differential change (control response minus response after treatment) in coronary perfusion pressure (CPP) during infusion of 8-phenyltheophylline (8-PT), diclofenac, and glibenclamide, respectively. The differential change in CPP with 8-PT and diclofenac given together (–48 ±7%) was found to be equivalent to the sum of their respective effects (–24±7 and –19±4%, respectively). Glibenclamide (0.3 M) reduced significantly hypoxia-induced vasodilatation (differential change in CPP of –27±6%) as well as the dilator response to 10 M adenosine and to the stable PGI2-analogue, iloprost. Forskolin-induced coronary vasodilatation in arrested hearts was slightly, but significantly, reduced by glibenclamide. Our results suggest that both cyclooxygenase products and adenosine, acting independently and concomitantly, contribute to the dilator response of coronary resistance vessels to hypoxia, in part through the activation of KATP channels. KATP channel activation by prostacyclin and adenosine may involve both cyclic adenosine monophosphate-dependent and independent pathways. 相似文献
7.
Chen L Wong MP Cheung LK Samaranayake LP Baum L Samman N 《Cancer Genetics and Cytogenetics》2005,159(1):37-43
A fine mapping of loss of heterozygosity (LOH) was performed in oral squamous cell carcinoma (OSCC), using 12 markers on 21q11.1 approximately q21.1. We studied 43 resected primary invasive tumors and their paired normal tissues, concurrent dysplasia or carcinoma in situ in separate areas from 8 of the specimens, and 6 local recurrent carcinomas. LOH status was compared between lesions of different phases of progression within the same patient. A high frequency of LOH was observed for D21S1410, D21S120, and D21S1433 (60% each) in the primary lesions, constituting two interstitial deleted regions encompassing eight known genes. Cases showing LOH of D21S120 were significantly associated with advanced clinical stages (III and IV; P=0.02). Consistent allelic loss was observed in 64.2% of the informative cases between the precursor lesions and their corresponding invasive tumors, and in 59.5% of those between the primary lesions and their recurrent counterparts. Fewer than half of the different lesions within a given patient showed discordant allelic loss for tested markers. Our results suggest that 21q11.1 approximately q21.1 harbors tumor suppressor genes in OSCC. Genetic divergence may develop during tumor clone evolution. 相似文献
8.
Summary The development ofEimeria dispersa Tyzzer, a parasite of bobwhite quail, in Madin-Darby bovine kidney cell cultures was investigated. Excysted sporozoites were inoculated into Leighton tubes containing cell monolayers on glass coverglasses and maintained in minimum essential medium supplemented with heat-inactivated fetal calf serum. Sporozoites became intracellular within 2 h. Sporozoite-shaped schizonts, schizonts with developing merozoites, and mature first-generation schizonts were seen 24 h postinoculation. Intracellular first-generation merozoites, second-generation trophozoites, and early second-generation schizonts containing two nuclei were first observed 72 h postinoculation. Second-generation schizonts containing developing merozoites as well as mature second-generation schizonts were first seen 96h postinoculation. Gametogony was not observed.DM
developing merozoite
- HN
host nucleus
- IM
intracellular merozoite
- M
merozoite
- N
nucleus
- R
refractile body
- RB
residual body
- V
parasitophorous vacuole 相似文献
9.
Modulation of calcium homeostasis as a mechanism for altering smooth muscle responsiveness in asthma
Airway hyperresponsiveness remains a defining characteristic of asthma. Traditional views assert that airway smooth muscle is an important structural effector cell in the bronchi that modulates bronchomotor tone induced by contractile agonists. New evidence, however, suggests that abnormalities in airway smooth muscle functions, induced by variety of extracellular stimuli, may play an important role in the development of airway hyperresponsiveness. Studies using isolated bronchial preparations or cultured cells show that inflammatory mediators and cytokines may alter calcium homeostasis in airway smooth muscle and render the cells nonspecifically hyperreactive to agonists. 相似文献
10.
Tlili A Charfedine I Lahmar I Benzina Z Mohamed BA Weil D Idriss N Drira M Masmoudi S Ayadi H 《Human mutation》2005,25(5):503
Approximately 80% of hereditary hearing loss is non-syndromic. Non-syndromic deafness is the most genetically heterogeneous trait. The most common and severe form of hereditary hearing impairment is autosomal recessive non-syndromic hearing loss (ARNSHL), accounting for approximately 80% of cases of genetic deafness. To date, 22 genes implicated in ARNSHL have been identified. Recently a gene, DFNB31/WHRN, which encodes a putative PDZ scaffold protein called whirlin, was found to be responsible for the ARNSHL DFNB31. We found evidence for linkage to the DFNB31locus in a consanguineous Tunisian family segregating congenital profound ARNSHL. Mutation screening of DFNB31/WHRNrevealed four nonpathogenic sequence variants and a novel frameshift mutation [c.2423delG] + [c.2423delG] that changed the reading frame and induced a novel stop codon at amino acid 818 ([p.Gly808AspfsX11] + [p.Gly808AspfsX11]). To determine the contribution of the DFNB31locus in the childhood deafness, we performed linkage analysis in 62 unrelated informative families affected with ARNSHL. No linkage was found to this locus. From this study, we concluded that DFNB31/WHRN is most likely to be a rare cause of ARNSHL in the Tunisian population. 相似文献