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31.
Brainstem maturation after antenatal steroids exposure in premature infants as evaluated by auditory brainstem-evoked response. 总被引:2,自引:0,他引:2
Sanjiv B Amin Mark S Orlando Larry E Dalzell Kathleen S Merle Ronnie Guillet 《Journal of perinatology》2003,23(4):307-311
OBJECTIVE: Antenatal steroids result in fetal lung maturation, but may retard brain development. Auditory brainstem-evoked response (ABR) is a noninvasive assessment of brainstem maturation. The objective of this study was to determine if antenatal steroids affect brainstem maturation in infants =32 weeks gestational age (GA). DESIGN/METHODS: Bilateral monaural ABR were performed within the first 24 hours using 80 db nHL unfiltered click stimuli at a repetition rate of 39.9/seconds. ABR waveforms were categorized into Response Types based on response replicability and peak identification. Absolute wave latencies and interpeak latencies were measured when applicable. Data were collected for antenatal steroid exposure, mode of delivery, chorioamnionitis in utero, exposure to illicit drugs, exposure to magnesium sulfate, mechanical ventilation and 5 minute Apgar score <5 minute. Infants with TORCH infections, unstable conditions, and chromosomal disorders were excluded. RESULTS: Of 186 infants studied, 130 received antenatal steroids. Data were analyzed in 2 week GA intervals. There was a significant difference (P<0.05) in race (29 vs 39% African-American), birth weight (1231 vs 1416 gm) and use of magnesium sulfate (60 vs 32%) among infants who did and did not receive antenatal steroids, respectively. There was no significant difference in the other parameters measured. Even after controlling for confounding variables, there was no difference between absolute wave latencies or interpeak latencies between groups at either 28 to 29 weeks' or 30 to 31 weeks' postmenstrual age. There was no significant difference in frequency distribution of ABR waveform Response Types between groups. CONCLUSIONS: Antenatal steroids have neither a deleterious nor beneficial effect on brainstem maturation as measured by ABR in infants at =32 weeks GA. 相似文献
32.
Philip AT Amin MB Tamboli P Lee TJ Hill CE Ro JY 《The American journal of surgical pathology》2000,24(9):1286-1290
Accurate pathologic staging of carcinomas of the urinary bladder involves assessment of invasion by the tumor into the bladder wall and beyond into perivesical soft tissue. The presence of tumor within perivesical soft tissue implies pathologic stage pT3 (AJCC/UICC system, 1997). In traditional textbooks of histology, anatomy, pathology, and in the literature, other than a single case report and a brief reference in another paper, there is no information on the presence of adipose tissue in the lamina propria or muscularis propria of the urinary bladder. Nine hundred forty-three sections from 139 cystectomy specimens were evaluated for the presence, location, and quantity of adipose tissue within the lamina propria and muscularis propria. The histology of the perivesical soft tissues and the nature of its delineation from muscularis propria were also analyzed. Adipose tissue was seen within the lamina propria in 53% (74 of 139) of cystectomies and in 17.6% (166 of 943) of the examined sections. It was located predominantly in the deep lamina propria (at or below the muscularis mucosae) in 81.1% (60 of 74) of the cystectomies and in 91% (151 of 166) of the sections. Within the lamina propria it was predominantly seen as small localized aggregates in 92% (153 of 166) of sections. All cases showed adipose tissue within the muscularis propria. Adipose tissue was identified within the superficial (inner) muscularis propria in 54% (512 of 943) of sections and was predominantly in small aggregates in 80.5% (412 of 512) of sections. It was in moderate to abundant quantities within the deep (outer) muscularis propria in 60.7% (572 of 943) of sections. The perivesical soft tissue was almost exclusively composed of adipose tissue with variable vascularity. Delineation of the perivesical adipose tissue from the deep (outer) muscularis propria was typically indistinct because muscle bundles of the latter haphazardly merged with the perivesical adipose tissue. Based on these findings, we conclude that adipose tissue is frequently present in the lamina propria and muscularis propria of the urinary bladder wall, and is usually scant in the former location and frequently abundant in the latter. Awareness of the high frequency of adipose tissue within the urinary bladder wall has prognostic and therapeutic implications. In transurethral resection of bladder tumor (TURBT) specimens, misinterpretation of tumor infiltrating adipose tissue within lamina propria (pT1) as perivesical soft tissue involvement (pT3) may potentially result in unwarranted aggressive management. Substaging of muscle invasive tumors should be performed in cystectomy specimens only, because the junction of muscularis propria and the perivesical adipose tissue is typically ill-defined. Muscularis propria adipose tissue in TURBT specimens may be erroneously assumed to be perivesical adipose tissue, potentially leading to overstaging of the primary tumor. 相似文献
33.
Erythropoietin and erythropoietin receptor expression in head and neck cancer: relationship to tumor hypoxia. 总被引:7,自引:0,他引:7
Murat O Arcasoy Khalid Amin Shu-Chuan Chou Zishan A Haroon Mahesh Varia James A Raleigh 《Clinical cancer research》2005,11(1):20-27
PURPOSE: Erythropoietin, an oxygen-regulated glycoprotein hormone, is a hematopoietic cytokine that stimulates erythropoiesis by binding to its cellular receptor [erythropoietin receptor (EPOR)]. The recombinant form of human erythropoietin is used to prevent or treat anemia in cancer patients. However, in a recent randomized, placebo-controlled trial involving patients receiving curative radiotherapy for squamous cell carcinoma of the head and neck, erythropoietin treatment was associated with poorer locoregional progression-free survival. The purpose of our study was to determine whether EPOR and its ligand erythropoietin are expressed in primary head and neck cancer. We also investigated the hypothesis that erythropoietin expression in malignant cells may be associated with the presence of tumor hypoxia, an important factor involved in resistance to radiation treatment, tumor aggressiveness, and poor prognosis. EXPERIMENTAL DESIGN: Twenty-one patients received an i.v. infusion of the hypoxia marker pimonidazole hydrochloride before multiple tumor biopsies. Contiguous sections from 74 biopsies were analyzed by immunohistochemistry for EPOR and erythropoietin expression and pimonidazole binding. RESULTS: EPOR expression was present in tumor cells in 97% of the biopsies. Coexpression of erythropoietin was observed in 90% of biopsies. Erythropoietin and pimonidazole adduct staining did not always colocalize within tumors, but there was a significant positive correlation between levels of microregional erythropoietin expression and pimonidazole binding. CONCLUSIONS: The coexpression of erythropoietin and EPOR in tumor cells suggests that erythropoietin may potentially function as an autocrine or paracrine factor in head and neck cancer. The expression of the hypoxia-inducible protein erythropoietin in tumor cells correlates with levels of tumor hypoxia. 相似文献
34.
Muhammad Ali Tariq Hamza Amin Bilal Ahmed Uzair Ali Ashar Mohiuddin 《Indian journal of ophthalmology》2022,70(6):1892
There is conflicting evidence for the association between smoking and dry eye disease (DED). We conducted a meta-analysis to determine the true relationship between smoking and DED. A systematic literature search was performed using electronic databases, including PubMed, Embase and Cochrane Library, till August 2021 to identify observational studies with data on smoking as risk factor of DED. Quality assessment of the included studies was conducted using Joanna Briggs Institute (JBI) critical appraisal checklists. The random-effects model was used to calculate the pooled odds ratio (OR). Heterogeneity was evaluated by Cochrane Q and I2 index; in addition, subgroup, sensitivity, and meta-regression analyses were performed. Publication bias was assessed using funnel plot and Egger’s regression test. A total of 22 studies (4 cohort and 18 cross-sectional studies) with 160,217 subjects met the inclusion criteria and were included in this meta-analysis. There is no statistically significant relationship between current smokers (ORadjusted = 1.14; 95% CI: 0.95–1.36; P = 0.15; I2 = 84%) and former smokers (ORadjusted = 1.06; 95% CI: 0.93–1.20; P = 0.38; I2 = 26.7%) for the risk of DED. The results remained consistent across various subgroups. No risk of publication bias was detected by funnel plot and Eggers’s test (P > 0.05). No source of heterogeneity was observed in the meta-regression analysis. Our meta-analysis suggest current or former smoking may not be involved in the risk of dry eye disease. Further studies to understand the mechanism of interaction between current smokers and formers smokers with DED are recommended. 相似文献
35.
Sarang Younesi Bahareh Yazdani Mohammad Mahdi Taheri Amin Pourandokht Saadati Soudabeh Jamali MohammadHossein Modarresi Shahram Savad Saloomeh Amidi Homayoun Razavi Soudeh GhafouriFard 《Journal of clinical laboratory analysis》2022,36(7)
BackgroundNowadays, neonatal screening has become an essential part of routine newborn care in the world. This is a non‐invasive evaluation that evaluated inborn errors of metabolisms (IEMs) using tandem mass spectrometry (LC‐MS/MS) for the evaluation of the baby''s risk of certain metabolic disorders.MethodsThis retrospective study was conducted on 39987 Iranian newborns who were referred to Nilou Medical Laboratory, Tehran, Iran, for newborn screening programs of IEMs. We incorporated second‐tier tests and secondary biomarkers to improve positive predictive value (PPV).ResultsStatistical data were recorded via call interviewing in 6–8 months after their screening tests. The overall prevalence of IEM was 1:975. The mean age of all participants was 3.9 ± 1.1 days; 5.1% of participants were over 13 days and 7.7% were preterm or underweight. A total of 11384 (29.4%) of the cases were born in a consanguineous family. The type of delivery was the cesarean section in 8332 (51.3%) valid cases. The neonatal screening results had an overall negative predictive value (NPV) of 100% and the overall PPV of 40.2%. The false‐positive rate was 0.15%.ConclusionThis study showed a high incidence of metabolic disease due to a high rate of consanguineous marriages in Iran and indicated that incorporation of second‐tier tests and secondary biomarkers improves PPV of neonatal screening programs. 相似文献
36.
A retrospective review of all patients older than 35 who underwent elective single blastocyst transfer was performed. Twenty-three of the 45 patients (51.1%) have an ongoing pregnancy or liveborn delivery, with a mean age of 37.3 years, demonstrating a clear role for elective single transfer in this relatively older IVF population. 相似文献
37.
38.
Antioxidant activity, free radical scavenging activity and phenolic content of red cabbage (Brassica oleracea var. capitata rubra), Chinese cabbage (Brassica rapa pekinensis var cylindrica), green cabbage (Brassica oleracea var capitata), mustard cabbage (Brassica juncea var rugosa) and Chinese white cabbage (Brassica rapa var chinensis), grown in Malaysia, were evaluated. Red cabbage had the highest antioxidant activity and phenolic content compared to the other cruciferous vegetables studied (p < 0.05). The contributions of all cruciferous vegetables to the antioxidant activity was >79%. The radical scavenging activity was in the order of Chinese white cabbage > red cabbage > mustard cabbage > Chinese cabbage > green cabbage. There was a significant difference (p < 0.05) in the means of scavenging activity observed between cabbage, Chinese cabbage and Chinese mustard. Phenolic content was significantly different (p < 0.05) among all the cruciferous vegetables studied, and was in the order of red cabbage > Chinese white cabbage > green cabbage > Chinese cabbage >mustard cabbage. The study indicated that red cabbage possessed the highest antioxidant capacity and phenolic compounds concentration among all the cruciferous vegetables studied. 相似文献
39.
Ramez A. Al-Mansob Herda Yati Katman Abdulnaser M. Al-Sabaeei Muhammad Zamzami Amin Al-Fakih Willy Kuay Wei Taha M. Jassam Jamal Alsharef Salihah B. Surol Nurul H. Yusof Suhana Koting 《Materials》2022,15(11)
This study aimed to evaluate the effects of carbon nanofibers (CNFs) on the performance of liquid epoxidized natural rubber (LENR)-modified asphalt. The physical, adhesion and rheological properties were determined by several tests such as penetration, elastic recovery, ring and ball softening point, Brookfield rotational viscometer, AFM and dynamic shear rheometer. LENR was used at concentrations of 3, 6, and 9%, while CNFs were used at contents of 0.3, 0.4, and 0.5% by weight of asphalt. Conventional test results showed that the increases in LENR and LENR/CNFs composite contents in binder leads to an increase in the hardness and consistency and a reduction in the temperature susceptibility of base asphalt. Adhesion results revealed that the addition of CNFs significantly increases the adhesion and bonding properties of base and rubberized binders. Rheological properties analysis exhibited that LENR improved the viscoelastic properties and permanent deformation resistance of asphalt at different temperatures and frequencies. On the other hand, it was found that the addition of CNFs significantly improves the stiffness, elasticity, and hardness of LENR-modified binders. The 6% LENR and 0.4% CNFs were found to be the optimum to enhance the physical, adhesion, and rheological properties of asphalt in this study. Thus, it can be stated that the addition of CNFs is promising to improve the performance of rubberized binders for high temperature applications. 相似文献
40.
Mahdi Asghari Ozma Amin Abbasi Sousan Akrami Masoud Lahouty Nayyer Shahbazi Khudaverdi Ganbarov Pasquale Pagliano Sahar Sabahi ükran Kse Mehdi Yousefi Sounkalo Dao Mohammad Asgharzadeh Hedayat Hosseini Hossein Samadi Kafil 《Le infezioni in medicina : rivista periodica di eziologia, epidemiologia, diagnostica, clinica e terapia delle patologie infettive》2022,30(2):180