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1.
Tissue ischemia, necrosis, and gangrene are uncommon but well-described complications of arterial catheterization in the neonate. Treatment options for progressive tissue necrosis following arterial embolization and/or vasospasm are limited in these patients secondary to unpredictable pharmacokinetics and risks associated with systemic anticoagulation or vasodilatation in newborns. We report a case of a multidose regimen of topical 2% nitroglycerin ointment for reversing severe tissue ischemia following peripheral arterial line placement. The favorable response in this infant suggests that topical nitroglycerin therapy should be considered as potential therapy to ameliorate the effects of vascular compromise following arterial line placement in neonates.  相似文献   
2.
Myeloid dendritic cells (DC) are representatives of a rare and phenotypically diverse population of professional antigen presenting cells possessing high functional heterogeneity and flexibility. Here we studied the phenotypic, functional and electrophysiological characteristics of KG-1 cells, an erythroleukemia model cell line, which shares morphological and physiological similarities with immature and mature myeloid DC. We compared the expression of internalizing receptors and other cell surface molecules, antigen uptake and migration of unstimulated and activated KG-1 cells with the characteristics of immature and mature DC. Unstimulated KG-1 cells were less potent in capturing extracellular materials than immature DC. In contrast to monocyte-derived DC KG-1 cells stimulated by PMA and ionomycin ceased to migrate along the MIP-3beta chemokine gradient despite their high expression of CCR7 chemokine receptor and MDR, a transporter implicated in DC migration. Moreover, we determined the ion channel repertoire of KG-1 cells before and after treatment with PMA and ionomycin by using the patch-clamp technique. We found that both unstimulated and activated KG-1 cells expressed time- and voltage-independent, ChTx sensitive intracellular Ca(2+)-gated potassium conductance suggesting the presence of K(Ca) channels in their membranes. Based on our results we propose that KG-1 cells resemble myeloid DC but also possess unique phenotypic, functional and electrophysiological characteristics.  相似文献   
3.
A recombinant pseudorabies (Aujeszky’s disease) virus (PrV) designated as vE16lac was constructed by deleting a 3-kbp DNA segment spanning the junction of long and short components of the viral genome, and by replacing the deleted segment with a lacZ-expression cassette. The aim of constructing this mutant was (a) to determine whether the terminal repeat (Tr) can serve as a template for the regeneration of the internal repeat (Ir), and (b) whether this deletion causes a reduction in the neuroinvasiveness of the virus. To analyze the mechanism of equalization, revertant viruses were selected and structurally characterized from vE16lac infection of PK-15 cells, mice and pigs. Because all revertants acquired Ir sequences identical to that of the wild-type virus, the equalization process occurred using the Tr as a template to reconstitute the Ir. We also found that the recombinant virus vE16lac was virulent in both pigs and mice. The data are discussed in view of studies performed with similar PrV mutants by other authors (Rall et al., 1992, Dean and Cheung, 1995 and Dean et al., 1996). This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
4.
The structural component of Gram- bacteria, endotoxin (ET), induces the release of endogenous mediators of sepsis. Attempts to remove these downstream molecules in vivo, have not improved survival. However, extracorporeal strategies such as continuous renal replacement therapy or therapeutic plasmapheresis have shown benefit. We are presenting an affinity-based extracorporeal technology for the removal of ET from whole blood. The small-scale device contains an adsorbent that removed 75% of ET present in whole blood. This affinity resin displayed good hemocompatibility regarding the coagulation pathway. Minimal platelet, neutrophil and complement activation were observed. There was also no evidence of consumption of coagulation factors or cell loss. In as much as ET participates in both the inflammatory and coagulation abnormalities in sepsis, this method represents an efficient and hemocompatible way to remove ET from whole blood, which, in an extracorporeal setting, may improve the outcome of sepsis.  相似文献   
5.
IntroductionSimultaneous gastrostomy tube (GT) and tracheostomy placement in young children offers potential benefit in limiting anesthetic exposure, but it is unknown whether combining these procedures introduces additional morbidity. This study compared outcomes after combined GT and tracheostomy placement versus GT placement alone among similar ventilator-dependent patients.MethodsVentilator-dependent children <2-years-old who underwent GT placement alone (MV-GT), simultaneous GT and tracheostomy placement (GT+T), and GT placement alone with a pre-existing tracheostomy (T-GT) were identified using 2012–2018 NSQIP-Pediatric Participant User Files. Multiple logistic regression models were used to compare outcomes while adjusting for other group differences.ResultsAmong 1100 children, 351 underwent MV-GT, 494 GT+T, and 255 T-GT. Major complications occurred in 23.6%, 17.0%, and 14.5% of the respective groups (p = 0.01). Major complications with GT+T were similar to T-GT (adjusted odds ratio [aOR]=1.19, 95%CI:0.78–1.83, p = 0.4) and lower than MV-GT (aOR=0.67, 95%CI:0.47–0.95, p = 0.02). Severe complications including mortality, cardiac arrest, and stroke were similar between the three groups (p = 0.8).ConclusionsChildren <2-years-old undergoing GT+T did not experience higher post-operative complications compared to children undergoing T-GT or MV-GT. Utilizing GT+T to limit anesthetic exposure may be reasonable within this high-risk population.Type of StudyTreatment StudyLevel of EvidenceLevel III  相似文献   
6.
gamma-amino butyric acid (GABA) is the major inhibitory neurotransmitter in the CNS, mediating fast inhibitory synaptic transmission, by activating GABAA receptors. However, these GABA-gated Cl- channels can also be excitatory, causing depolarization, and increasing Ca2+ entry via voltage-operated Ca2+ channels (VOCCs). Evidence exists for excitatory ionotropic GABA receptors in anterior pituitary cells, including gonadotropes, but these have not been directly characterized and their pharmacology remains controversial. Here we have measured the cytosolic Ca2+ concentration ([Ca2+]i) in alphaT3-1 gonadotropes, to test for expression of excitatory GABA receptors. The GABAA agonists, GABA and muscimol, both caused rapid, robust and dose-dependent increases in [Ca2+]i (EC50 values 2.7 and 1 microM), whereas the GABAB agonist, baclofen, did not. The GABAA antagonist, bicuculline, inhibited muscimol's effect, whereas the GABAB antagonist, phaclofen, did not. The neuroactive steroid 5alpha-pregnan-3alpha-ol-11,20-dione (an allosteric activator of GABAA receptors) increased [Ca2+]i, and this effect, like that of muscimol, was inhibited by picrotoxin. The muscimol effect on [Ca2+]i was blocked by the VOCC antagonist, nifedipine, or by Ca2+-free medium. When cells were pretreated with muscimol this increased the spike phase of the [Ca2+]i response to subsequent stimulation with gonadotropin-releasing hormone (GnRH). Similar amplification was seen in muscimol-pretreated cells stimulated with GnRH in Ca2+-free medium, but not when cells were pretreated with muscimol in Ca2+-free medium. The amplification was not, however, GnRH receptor-specific, because the spike response to ionomycin was also increased by muscimol pretreatment. These data provide the first direct evidence for expression of excitatory GABAA receptors, and the first demonstration of acute steroid effects, on GnRH-responsive pituitary cells. They also reveal a novel mechanism by which GABAA activation modulates GnRH action, raising the possibility that this may also influence gonadotrophin secretion from non-immortalized gonadotropes.  相似文献   
7.
Objective: To assess the psychological condition of men at the start of the infertility work-up.

Methods: Men seeking an infertility evaluation for the first time were recruited. Depression and anxiety symptoms and subjective psychological burden were assessed with the Beck Depression Inventory (BDI), the Spielberger State-Trait Anxiety Inventory (STAI), and a visual analog scale (VAS).

Results: Data from 113 patients were analyzed. The mean age of the patients was 33.3 (range: 23–54) years, whereas the mean duration of infertility was 16.3 (range: 0–96) months. Results from the BDI and STAI were 2.24 (SD: ±3.18) and 33.74 (SD: ±8.04). Mild depressive symptoms were found in 4.5% of patients, whereas anxiety reached an abnormal level in 4.9%. There were significant correlations between the results from the BDI score and the duration of infertility (p?=?.024), whereas the STAI and VAS scores showed no similar connection (p?=?.142 and p?=?.261, respectively). Among patients with infertility longer than 2 years, mild depressive symptoms occurred in 23.1%.

Conclusion: Among men, the levels of depressive and anxiety symptoms were low at the start of the infertility work-up. Depressive symptom levels increased significantly with the duration of infertility, whereas anxiety levels and VAS scores did not demonstrate a similar correlation.  相似文献   
8.
Viral infections during pregnancy raise several clinical challenges, including birth defects in the offspring. Thus, this systematic review and meta-analysis aims to prove and highlight the risk of birth defects after first-trimester maternal influenza infection. Our systematic search was performed on 21 November 2022. Studies that reported maternal influenza infection in the first trimester and non-chromosomal congenital abnormalities were considered eligible. We used odds ratios (OR) with 95% confidence intervals (CIs) to measure the effect size. Pooled ORs were calculated with a random effects model. Heterogeneity was measured with I² and Cochran’s Q tests. We found that first-trimester maternal influenza was associated with increased odds of developing any type of birth defects (OR: 1.5, CI: 1.30–1.70). Moreover, newborns were more than twice as likely to be diagnosed with neural tube defects (OR: 2.48, CI: 1.95–3.14) or cleft lip and palate (OR: 2.48, CI: 1.87–3.28). We also found increased odds of developing congenital heart defects (OR: 1.63, CI: 1.27–2.09). In conclusion, influenza increases the odds of non-chromosomal birth defects in the first trimester. The aim of the present study was to estimate the risk of CAs in the offspring of mothers affected by first-trimester influenza infection.  相似文献   
9.
10.
The liberal use of upper endoscopy has led to an increased detection of gastric and duodenal polyps, which are identified in as many as 6 and 4.6% of patient examinations, respectively. Gastroduodenal polyps are a heterogeneous group of lesions that can be neoplastic or non‐neoplastic (e.g. hyperplastic or heterotopical). Most polyps present characteristic topographical features, as well as endoscopic appearance and size. Evaluation of the surrounding mucosa is essential in assessing the underlying pathology (e.g. Helicobacter pylori, autoimmune gastritis or inherited polyposis syndromes). Phylogenetically, gastric and duodenal polyps can be classified according to the epithelial compartment from which they derive. Polyps that arise from the surface epithelium can either be of foveolar or intestinal type, and they can develop from either the native mucosa or the metaplastic epithelium (gastric intestinal metaplasia or duodenal foveolar metaplasia). Other polyps develop from the deeper glandular component, such as pyloric/oxyntic gland derived subtypes. In this review we focus upon epithelial polyps, with an emphasis on the most common and clinically relevant lesions, and present recently described entities.  相似文献   
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