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121.
Background
The impact of mechanical ventilation on the incidence of intraventricular hemorrhage (IVH) in very low birth weight (VLBW) infants is unknown, simply because the vast majority of these infants have been routinely intubated and mechanically ventilated. There is a growing interest in the use of early nasal continuous positive airway pressure (ENCPAP) and avoiding mechanical ventilation.Objectives
To examine the role of mechanical ventilation since delivery room in determining severe IVH in VLBW infants in two neonatal units that follow the same strategy of respiratory management using ENCPAP.Methods
We collected data on delivery room intubation and mechanical ventilation during the first 3 days of life in VLBW infants. Logistic regression model was constructed to test the relationship between early mechanical ventilation and the diagnosis of severe IVH after controlling for significant confounding variables, such as BW, gender, duration of mechanical ventilation, and partial pressure of CO2 (PCO2).Results
Of the studied 340 VLBW, 35 infants had severe IVH; most of them received mechanical ventilation that started either in the delivery room (n = 12) or during the first (n = 10) and second (n = 3) days of life. Severe IVH was independently associated with lower BW, mechanical ventilation in the delivery room, and the cumulative duration of mechanical ventilation during the first 3 days. The adjusted odds ratio for severe IVH in infants intubated in delivery room was (OR = 2.7, CI: 1.1–6.6, P = 0.03). Severe IVH was not associated with gender, prenatal steroids, early sepsis, or patent ductus arteriosus.Conclusions
Mechanical ventilation plays a role in predicting severe IVH. Both the time at which ventilation was initiated and the duration of ventilation are important determinants of severe IVH. Risk for severe IVH in infants who were never intubated in delivery room or during the first 3 days of life is miniscule. 相似文献122.
Virginia Hill Rice Thomas N. Templin Janet K. Harden Elizabeth S. Jenuwine Ibrahim Abdulhamid Adnan Hammad 《The Journal of adolescent health》2019,64(3):333-339
Purpose
The purpose of this study was to determine the prevalence of respiratory and/or physical fitness health problems in adolescent (ages 18–21) water pipe (WP) smokers (with or without cigarette smoking), cigarette-only smokers, and nonsmokers.Methods
A comparative four-group study design was used to recruit a non–probability sample of 153 WP smokers only, 103 cigarette smokers only, and 102 cigarette+WP smokers along with 296 nonsmokers. Our hypothesis was that youth who smoked WPs and/or cigarettes would report more respiratory problems and/or poorer physical fitness than those who did not smoke.Results
The results showed that coughs were significantly associated with smoking in all three of the smoking groups (p < .05). Cigarette-only smokers reported the most adverse outcomes with more wheezing, difficulty breathing, and less ability to exercise without shortness of breath. A dose-response analysis showed similar patterns of adverse health effects for both WP and cigarette smokers. The combined use of both products was not appreciably worse than smoking one product alone. This could be due to cigarette+WP smokers' reporting using less of the respective products when only one product was smoked.Conclusions
Even during the adolescent years, WP and/or cigarette smoking youth experienced reportable negative health effects. 相似文献123.
124.
Philip J. F. Leute Isabel Hoffmann Ahmed Hammad Stefan Lakemeier Hans-Michael Klinger Mike H. Baums 《Journal of orthopaedics and traumatology》2017,18(2):111-120
Background
Aseptic loosening after total hip arthroplasty is likely related to nicotine ingestion. However, aseptic loosening as a direct consequence of smoking habits has not been described with regard to proximal mega-prosthetic femoral replacement. The aim of the present study was to evaluate the association between nicotine consumption and aseptic loosening rates after proximal mega-prosthetic femoral replacement.Materials and methods
A consecutive series of patients who received mega-prosthetic replacement of the proximal femur at our hospital between 2005 and 2015 were included. Their files were reviewed and evaluated for the influence of smoking on aseptic loosening rates. All living patients were invited to complete a functional follow-up assessment at our clinic.Results
Twenty-six patients with 27 prostheses were included. Five patients were active smokers, and 21 patients were non-smokers. Aseptic loosening was observed in three patients in the smoking group, whereas none of the non-smokers developed aseptic loosening. Fisher’s exact test showed a relationship between nicotine consumption and aseptic loosening of the prostheses (p = 0.003).Conclusions
Smoking increases the likelihood of aseptic loosening after proximal mega-prosthetic femoral replacement.Level of evidence
Level 4 according to Oxford Centre of Evidence-Based Medicine 2011.125.
126.
Mokhtar M Sammour OA Hammad MA Megrab NA 《International journal of pharmaceutics》2008,361(1-2):104-111
Proniosomal gels or solutions of flurbiprofen were developed based on span 20 (Sp 20), span 40 (Sp 40), span 60 (Sp 60), and span 80 (Sp 80) without and with cholesterol. Nonionic surfactant vesicles (niosomes) formed immediately upon hydrating proniosomal formulae. The entrapment efficiency (EE%) of flurbiprofen (a poorly soluble drug) was either determined by exhaustive dialysis of freshly prepared niosomes or centrifugation of freeze-thawed vesicles. The influence of different processing and formulation variables such as surfactant chain length, cholesterol content, drug concentration, total lipid concentration, negatively or positively charging lipids, and the pH of the dispersion medium on flurbiprofen EE% was demonstrated. Also, the release of the prepared niosomes in phosphate buffer (pH 7.4) was illustrated. Results indicated that the EE% followed the trend Sp 60 (C(18))>Sp 40 (C(16))>Sp 20 (C(12))>Sp 80 (C(18)). Cholesterol increased or decreased the EE% depending on either the type of the surfactant or its concentration within the formulae. The maximum loading efficiency was 94.61% when the hydrating medium was adjusted to pH 5.5. Increasing total lipid or drug concentration also increased the EE% of flurbiprofen into niosomes. However, incorporation of either dicetyl phosphate (DCP) which induces negative charge or stearyl amine (SA) which induces positive charge decreased the EE% of flurbiprofen into niosomal vesicles. Finally, in vitro release data for niosomes of Sp 40 and Sp 60 showed that the release profiles of flurbiprofen from niosomes of different cholesterol contents is an apparently biphasic release process. As a result, this study suggested the potential of proniosomes as stable precursors for the immediate preparation of niosomal carrier systems. 相似文献
127.
Ethan H. Mereish Hammad S. N'cho Carlton E. Green Maryam M. Jernigan Janet E. Helms 《Behavioral medicine (Washington, D.C.)》2016,42(3):190-196
Discrimination is related to depression and poor self-esteem among Black men. Poorer self-esteem is also associated with depression. However, there is limited research identifying how self-esteem may mediate the associations between discrimination and depressive symptoms for disparate ethnic groups of Black men. The purpose of this study was to examine ethnic groups as a moderator of the mediating effects of self-esteem on the relationship between discrimination and depressive symptoms among a nationally representative sample of African American (n = 1201) and Afro-Caribbean American men (n = 545) in the National Survey of American Life. Due to cultural socialization differences, we hypothesized that self-esteem would mediate the associations between discrimination and depressive symptoms only for African American men, but not Afro-Caribbean American men. Moderated-mediation regression analyses indicated that the conditional indirect effects of discrimination on depressive symptoms through self-esteem were significant for African American men, but not for Afro-Caribbean men. Our results highlight important ethnic differences among Black men. 相似文献
128.
Ayman Hammad Enas M. Hammad Samir Elhanbly Sherif R. El-Bassiony Mohammad F. Al-Harrass 《Autoimmunity》2016,49(1):31-40
There are no reports about the association of interleukin (IL)-17A and IL-17F gene polymorphism and susceptibility to pediatric systemic lupus erythematosus (pSLE). Objective: To examine the possible role of IL-17A rs2275913, IL-17F rs763780 and rs2397084 polymorphisms as risk factors for pSLE in a cohort of Egyptian children and to investigate their association with the clinico-pathological features including lupus nephritis (LN). Methods: Typing of IL-17A and IL-17F polymorphisms was done using restriction fragment length polymorphism for 115 children with SLE and 259 age- and sex-matched healthy controls. Results: No significant differences were found between pSLE patients and healthy controls for the allele and genotype frequencies of IL-17A rs2275913, IL-17F rs763780 and rs2397084 (p?>?0.05). However, the combined genotype GGAGAA and the haplotype GGA had significant association with pSLE (pc?=?0.042 and <0.001, respectively). The AA genotype of IL-17F rs763780 is more frequent in female patients (p?=?0.002) and the AA genotype of IL-17F rs2397084 is more associated with positivity of ds-DNA (p?=?0.007). No more associations were found for the demographic and clinical data of pSLE patients including risk of LN development, risk of non-remission, overall survival, activity and chronicity indices. Conclusion: The GGAGAA combined genotype and the GGA haplotype of IL-17A rs2275913, IL-17F rs763780 and rs2397084 can be considered risk factors for the development of SLE in Egyptian children. IL-17A rs2275913, IL-17F rs763780 and rs2397084 are not related to the LN development, SLE disease activity or overall survival. 相似文献
129.
130.