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61.

Background:

Among different categories of sedative agents, benzodiazepines have been prescribed for more than three decades to patients of all ages. The effective and predictable sedative and amnestic effects of benzodiazepines support their use in pediatric patients. Midazolam is one of the most extensively used benzodiazepines in this age group. Oral form of drug is the best accepted route of administration in children.

Objectives:

The purpose of this study was to compare the efficacy and safety of a commercially midazolam syrup versus orally administered IV midazolam in uncooperative dental patients. Second objective was to determine whether differences concerning sedation success can be explained by child‘s behavioral problems and dental fear.

Patients and Methods:

Eighty eight uncooperative dental patients (Frankl Scales 1,2) aged 3 to 6 years, and ASA I participated in this double blind, parallel randomized, controlled clinical trial. Midazolam was administered in a dose of 0.5 mg/kg for children under the age 5 and 0.2 mg/kg in patients over 5 years of age. Physiologic parameters including heart rate, respiratory rate, oxygen saturation and blood pressure were recorded. Behavior assessment was conducted throughout the course of treatment using Houpt Sedation Rating Scale and at critical moments of treatment (injection and cavity preparation) by North Carolina Scale. Dental fear and behavioral problems were evaluated using Child Fear Schedule Survey-Dental Subscale (CFSS-DS), and Strength and Difficulties Questionnaire (SDQ). Independent t-test, Chi-Square, and Pearson correlation were used for statistical analysis.

Results:

Acceptable overall sedation ratings were observed in 90% and 86% of syrup and IV/Oral group respectively; Chi-Square P = 0.5. Other domains of Houpt Scale including: sleep, crying and movement were also not significantly different between groups. Physiological parameters remained in normal limits during study without significant difference between groups.

Conclusions:

“Orally administered IV midazolam” preparation can be used as an alternative for commercially midazolam syrup.  相似文献   
62.
A theoretical analysis for describing the dimeric assemblies of high-valent manganese(v)-oxo meso-tetraphenylporphyrin (TPP) ([(TPP)MnVO]22+) and meso-tetrakis(pentafluorophenyl)porphyrin (TPFPP) ([(TPFPP)MnVO]22+) in the presence of axial N-donor ligands is presented. Our theoretical results revealed two types interactions in dimers: a sandwich-like interaction between phenyl rings of porphyrin molecules, and a non-bonded T-shape interaction between nitrogen donors attached to Mn centers. The curvature in the geometry of porphyrin in the [(TPP)MnVO]22+/N-donor system is significantly smaller than that of [(TPFPP)MnVO]22+/N-donor system. Moreover, the Mn–N(ax) distances in [(TPFPP)MnVO]22+/N-donor system are shorter than those of [(TPP)MnVO]22+/N-donor system. Also, the donor–acceptor interaction between the imidazoles and the Mn centers are stronger than those of the other ligands in both porphyrins. These results are supported by atoms in molecules (AIM) and natural bond orbital (NBO) analysis.

A DFT analysis for describing the dimeric assemblies of high-valent manganese(v)-oxo meso-tetraphenylporphyrin ([(TPP)MnVO]22+) and meso-tetrakis(pentafluorophenyl)porphyrin ([(TPFPP)MnVO]22+) in the presence of axial N-donor ligands is presented.  相似文献   
63.
Purpose: Detection of body stuffers is challenging in emergency departments. Because of the small size of baggies, plain radiograph is of little value in most suspects. On the other hand, abdomen CT scan is burdened by high cost and radiation dose. This study was performed to compare the image quality, radiation dose and accuracy of low-dose CT scan in comparison with standard dose.

Material and methods: In this prospective study, suspected body stuffers who were referred to the radiology department underwent two different protocols of abdominal non-contrast CT scan simultaneously: low-dose (with equivalent dose to conventional abdominal x-ray) and standard dose. Standard dose CT scan was considered as the reference. Low-dose CT scans were evaluated for detection of baggies by two radiologists blinded to the result of standard dose CT. Image quality, noise, dose-length product (DLP) and effective dose (ED) compared between two groups.

Results: The study consisted of 40 patients (33.38?±?7.4 years). Standard dose CT evaluation was positive in 22 patients (55%). In comparison with standard dose CT scan, low-dose group had a sensitivity of 86%, specificity of 100%, PPV and NPV of 100% and 86%. The accuracy of low-dose CT scan for detection of baggies larger than 1?cm was 100%. However, from the 3 cases that could not be detected with low dose protocol, one had CT features suspected for baggies rupture which was intubated and later deceased. Noise average of low-dose protocol, was approximately 7 times greater than standard dose group, while DLP and ED were 9.7 times less.

Conclusion: Low dose CT scan appears to be an appropriate screening method for body stuffers, especially when the baggies are larger than one centimeter. However, in the presence of severe clinical symptoms, a standard dose CT scan will be more helpful due to better image quality especially in suspected ruptured baggies.  相似文献   
64.
LKB1 is a significant tumor suppressor and epigenetic regulator playing a vital role in different types of cancers. SHMT1 and GLDC are two critical genes of the epigenetic pathway influenced by LKB1. As epigenetic is the major cause of AML pathogenesis, this study aimed at investigating LKB1, SHMT1, and GLDC gene expression levels in acute myeloid leukemia patients. The present study was conducted on LKB1, SHMT1, and GLDC gene expression levels in 60 de novo AML samples and 30 normal controls using real-time RT-PCR. The results showed that LKB1 and SHMT1 have respectively a significantly lower (P < 0.05) and higher (P < 0.05) expression level than that of normal controls. Furthermore, the correlation between LKB1 with SHMT1 and GLDC was significant and positive (P value: 0.015, r: 0.299). Positive findings confirm that metabolic pathways alongside the LKB1 association drive the epigenetic axis and its substrate production. Therefore, it can be concluded that the newly-discovered pathway in the pathogenesis of this disease provides new insights into the design of therapeutic targets.  相似文献   
65.
66.
CCR5 is an important chemokine receptor involved in the recruitment of specific anti‐viral immune cells (e.g., NK cells and T cytotoxic cells) to the liver. Previous studies indicated that the Δ 32 mutation in CCR5 gene led to inactivation of CCR5. Several conflicting studies have suggested that this mutation may be associated with either recovery or persistence of HBV infection. The main purpose of this study was to compare the frequency of the Δ 32 mutation within the CCR5 gene in a group of patients infected chronically with HBV with healthy individuals from South‐East of Iran. Sixty patients with chronic HBV infection as well as 300 age‐, and sex‐match healthy individuals were enrolled in this study. Gap‐PCR was applied to determine the frequency of CCR5 Δ 32 mutation in both groups. The results demonstrated that none of the patients infected with HBV carried the CCR5 Δ 32 mutation while, 3 (1%) of the healthy individuals were found to be heterozygotic for this mutation. The CCR5 Δ 32 mutation is not a prevalent mutation in either the patients infected chronically with HBV or their health counterparts in the South‐East region of Iran. This may be attributed to either different genetic settings of the investigated population or lack of any significant correlation between this mutation and HBV pathogenicity. J. Med. Virol. 85: 964–968, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
67.
68.
Sport Sciences for Health - The widespread prevalence and mortality of coronavirus diseases-2019 (COVID-19) lead many researchers to study the SARS-CoV-s2 infection to find a treatment for this...  相似文献   
69.
Bone marrow-derived mesenchymal stem cells (MSCs) have the capacity to regenerate renal tubule epithelia and repair renal function without fusing with resident tubular cells. The goal of the present project was to investigate the role of MSCs secreted cytokines on tubule cell viability and regeneration after a toxic insult, using a conditionally immortalized human proximal tubule epithelial cell (ciPTEC) line. Gentamicin was used to induce nephrotoxicity, and cell viability and migration were studied in absence and presence of human MSC-conditioned medium (hMSC-CM) i.e. medium containing soluble factors produced and secreted by MSCs. Exposure of ciPTEC to 0–3000 μg/ml gentamicin for 24 h caused a significant dose-dependent increase in cell death. We further demonstrated that the nephrotoxic effect of 2000 μg/ml gentamicin was recovered partially by exposing cells to hMSC-CM. Moreover, exposure of ciPTEC to gentamicin (1500–3000 μg/ml) for 7 days completely attenuated the migratory capacity of the cells. In addition, following scrape-wounding, cell migration of both untreated and gentamicin-exposed cells was increased in the presence of hMSC-CM, as compared to exposures to normal medium, indicating improved cell recovery. Our data suggest that cytokines secreted by MSCs stimulate renal tubule cell regeneration after nephrotoxicity.  相似文献   
70.
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