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101.
Yazdy MM Honein MA Xing J 《Birth defects research. Part A, Clinical and molecular teratology》2007,79(1):16-23
BACKGROUND: Folic acid fortification in the United States became mandatory January 1, 1998, to reduce the occurrence of neural tube defects (NTDs). We evaluated the impact of folic acid fortification on orofacial clefts using United States birth certificate data for 45 states and the District of Columbia. METHODS: Prevalence ratios (PRs) were calculated comparing orofacial cleft prevalence among births prefortification (1/1990-12/1996) and postfortification (10/1998-12/2002), based on fortification status at conception. The JoinPoint Regression Program and exponentially weighted moving average charts (EWMA) were used to assess the timing of any statistically significant changes in prevalence. Data were stratified by maternal race/ethnicity, age, smoking, and timing of prenatal care. RESULTS: Orofacial clefts declined following folic acid fortification (PR=0.94; 95% CI: 0.92-0.96). The EWMA chart flagged a significant decrease in the fourth quarter of 1998. The JoinPoint graph had one change in slope, with a significant quarterly percent change (-0.34) between 1996 and 2002. The decline in orofacial clefts occurred in non-Hispanic Whites but not other racial/ethnic groups, nonsmokers but not women who reported smoking during pregnancy, and women who received prenatal care in the first trimester but not women who began receiving care later in pregnancy. CONCLUSION: Folic acid fortification in the United States was associated with a small decrease in orofacial cleft prevalence, with the timing of the decline consistent with the introduction of fortification. The decline is much smaller than that observed for NTDs, but nonetheless suggests an additional benefit of this public health intervention. 相似文献
102.
Bin Sun Mahsa Hadidi Jose Santiago Nuñez Benben Song Gilbert E. Tumambac Ken Wong Gregor Kalinowski James J. Hathcock 《Biotechnology progress》2024,40(1):e3400
In the production of biological therapeutics such as monoclonal antibodies (mAbs), ultrafiltration and diafiltration (UF/DF) are widely regarded as effective downstream processing steps capable of removing process equipment related leachables (PERLs) introduced upstream of the UF/DF step. However, clearance data available in the literature are limited to species with low partition coefficients (log P) such as buffer ions, hydrophilic organic compounds, and some metal ions. Additional data for a wide range of PERLs including hydrophobic compounds and elemental impurities are needed to establish meaningful, comprehensive safety risk assessments. Herein, we report the results from studies investigating the clearance of seven different organic PERLs representing a wide range of characteristics (i.e., log P (−0.3 to 18)), and four model elements with different chemical properties spiked into a mAb formulation at 10 ppm and analyzed during clearance using gas chromatography–mass spectrometry (GC–MS), liquid chromatography-photodiode-array-mass spectrometry (LC-PDA-MS), and inductively coupled plasma mass spectrometry (ICP-MS). The clearance data showed ideal clearance and sieving of spiked organic PERLs with log P < 4, partial clearance of PERLs with 4 < log P < 9, and poor clearance of highly hydrophobic PERLs (log P > 9) after nine diafiltration volumes (DVs). Supplemental clearance studies on seven additional PERLs present at much lower concentration levels (0.1–1.5 ppm) in the mAb formulation upstream of UF/DF and three PERLs associated with the tangential flow filtration (TFF) equipment also demonstrated the similar correlations between log P and % clearance. For model elements, the findings suggest that UF/DF in general provides ideal clearance for elements. Evidence showed that the UF/DF process does not only help mitigate leachables risk from PERLs introduced upstream of UF/DF, but also from the TFF operation itself as all three TFF-related PERLs were effectively cleared. Overall, the UF/DF clearance presented in this work demonstrated whereas highly hydrophobic PERLs and elements that exist as charged species, particularly transition metal ions, may not be as effectively cleared and thus warrant further risk assessment; hydrophilic and some hydrophobic PERLs (log P < 4) are indeed well-cleared and thus present a lower overall safety risk. 相似文献
103.
104.
Fahimipour F Nouruzian M Anvari M Tafti MA Yazdi M Khosravi M Dehghannayeri Z Sabounchi SS Bayat M 《Indian journal of experimental biology》2011,49(5):357-361
Under general anesthesia and sterile conditions, incision wound was induced in the hard palate mucosa of adult male mice. The wounds of groups 1 and 2 were irradiated daily with He-Ne laser at 3 and 7.5 J/cm2 for 120 and 300 s, respectively, while the incision wound of group 3 not exposed served as controls. On day 3 of injury, the laser-treated wounds contained significantly lower neutrophils than the wounds in the control group. By day 7 after injury, the laser-treated wounds contained significantly more fibroblasts and at the same time contained significantly fewer macrophages. In conclusion, an acceleration of the wound healing process of experimental wounds in the hard palate mucosa of mice at low-level laser therapy with a He-Ne laser at energy densities of 3 and 7.5 J/cm2 was observed. 相似文献
105.
Optimizing Conditions for Rat Pancreatic Islets Isolation 总被引:2,自引:0,他引:2
Many procedures have been described for rat pancreatic islet isolation. Several factors contribute to the pancreatic islet
isolation outcome. One of the main problems in islet isolation procedure is the formation of a viscouse, gellike structure
during collagenase digestion which entraps the free islets and decrease islet yield after density gradient purification. This
issue has not been addressed in most techniques described for rat islet isolation. We examined effect of various factors to
eliminate formation of gellike material and improve the islets yields. Islet isolation was performed on 26 adult male Wistar
Albino rats weighing between 280 and 350 g. We have observed that several factors affect pancreatic islet isolation. Optimum
Collagenase enzyme concentration, maintaining pH range between 7.7 and 7.9 in digestion solution, incubation temperature at
38±1 °C and addition of Calcium ion decreased the formation of gellike materials and increased islet yield. Addition of Glycerol
as a gelatin solvent has also been helpful in the reduction or complete elimination of gellike material. Precise optimization
of rat islet isolation procedure is useful to improve the islet yield in islet transplantation studies. 相似文献
106.
Sousan Mousavi Roya Moallem Seyed Mahdi Hassanian Mahsa Sadeghzade Ramin Mardani Gordon A. Ferns Majid Khazaei Amir Avan 《Journal of cellular physiology》2019,234(8):12422-12432
Colorectal cancer (CRC) is the third most common cause of cancer-related death in men and women in many countries. Early detection of CRC helps to prevent the advanced stages of the disease, and may thereby improve the survival of these patients. A noninvasive test with high specificity and sensitivity is required for this. Exosomes are lipid bilayer membrane nanovesicles that are released into most body fluids and especially in the microenvironment of cancer. They carry various proteins, lipids, and nucleic materials such as DNA, RNA, messenger RNA (mRNA), and microRNA (miRNA), and may also alter the function of target cells. In this review, we aimed to describe the biogenesis, composition, function, and the role of tumor-derived exosomes in cancer progression. Moreover, their applications in tumor diagnosis and treatment are described, with a particular focus on CRC. 相似文献
107.
Snow regimes affect biogeochemistry of boreal ecosystems and are altered by climate change. The effects on plant communities,
however, are largely unexplored despite their influence on relevant processes. Here, the impact of snow cover on understory
community composition and below-ground production in a boreal Picea abies forest was investigated using a long-term (8-year) snow cover manipulation experiment consisting of the treatments: snow
removal, increased insulation (styrofoam pellets), and control. The snow removal treatment caused longer (118 vs. 57 days)
and deeper soil frost (mean minimum temperature −5.5 vs. −2.2°C) at 10 cm soil depth in comparison to control. Understory
species composition was strongly altered by the snow cover manipulations; vegetation cover declined by more than 50% in the
snow removal treatment. In particular, the dominant dwarf shrub Vaccinium myrtillus (−82%) and the most abundant mosses Pleurozium schreberi (−74%) and Dicranum scoparium (−60%) declined strongly. The C:N ratio in V. myrtillus leaves and plant available N in the soil indicated no altered nitrogen nutrition. Fine-root biomass in summer, however, was
negatively affected by the reduced snow cover (−50%). Observed effects are attributed to direct frost damage of roots and/
or shoots. Besides the obvious relevance of winter processes on plant ecology and distribution, we propose that shifts in
the vegetation caused by frost damage may be an important driver of the reported alterations in biogeochemistry in response
to altered snow cover. Understory plant performance clearly needs to be considered in the biogeochemistry of boreal systems
in the face of climate change. 相似文献
108.
Purpose
To study the ability of volumetric spectral domain optical coherence tomography (SD-OCT) to perform quantitative measurement of the choroidal vasculature in vivo.Methods
Choroidal vascular density and vessel size were quantified using en face choroidal scans from various depths below the retinal pigment epithelium (RPE) in 58 eyes of 58 patients with either epiretinal membranes (ERM), early age-related macular degeneration (AMD), or reticular pseudo-drusen (RPD). For each patient, we used the macular volume scan (6×6 mm cube) for vessel quantification, while high-definition (HD) cross-section raster scans were used to qualitatively assess vascularity of the choroidal sub-layers, and measure choroidal thickness.Results
Of the 58 patients, more were female (66% versus 34% male), of whom 14 (24%) had ERM, 11 (19%) early AMD, and 33 (57%) RPD. Compared to intact choriocapillaris in all ERM (100%), none of the RPD and only 5/11 (45%) early AMD eyes had visible choriocapillaris on either cross section or C-scans (p-value<0.001). When comparing select regions from the most superficial C-scans, early AMD group had lowest vascular density and RPD had highest (p-value 0.04). Qualitative evaluation of C-scans from all three groups revealed a more granular appearance of the choriocapillaris in ERM versus increased stroma and larger vessels in the RPD eyes.Conclusions
SD-OCT can be used to qualitatively and quantitatively assess choroidal vascularity in vivo. Our findings correlate to previously reported histopathologic studies. Lack of choriocapillaris on HD cross-sections or C-scans in all RPD and about half of early AMD eyes suggests earlier choroidal involvement in AMD and specifically, RPD. 相似文献109.
Larijani B Arjmand B Amoli MM Ao Z Jafarian A Mahdavi-Mazdah M Ghanaati H Baradar-Jalili R Sharghi S Norouzi-Javidan A Aghayan HR 《Cell and tissue banking》2012,13(4):569-575
It has been predicted that one of the greatest increase in prevalence of diabetes will happen in the Middle East bear in the next decades. The aim of standard therapeutic strategies for diabetes is better control of complications. In contrast, some new strategies like cell and gene therapy have aimed to cure the disease. In recent years, significant progress has occurred in beta-cell replacement therapies with a progressive improvement of short-term and long term outcomes. In year 2005, considering the impact of the disease in Iran and the promising results of the Edmonton protocol, the funding for establishing a current Good Manufacturing Practice (cGMP) islet processing facility by Endocrinology and Metabolism Research Center was approved by Tehran University of Medical Sciences. Several islet isolations were performed following establishment of cGMP facility and recruitment of all required equipments for process validation and experimental purpose. Finally the first successful clinical islet isolation and transplantation was performed in September 2010. In spite of a high cost of the procedure it is considered beneficial and may prevent long term complications and the costs associated with secondary cares. In this article we will briefly describe our experience in setting up a cGMP islet processing facility which can provide valuable information for regional countries interested to establish similar facilities. 相似文献
110.
Mahsa Sedighi Farzaneh Vahabzadeh Seyed Morteza Zamir Abbas Naderifar 《Biotechnology and Bioprocess Engineering》2013,18(4):827-833
In the present study, a pure culture of Ralstonia eutropha was used to degrade gaseous ethanethiol. Ethane thiol at various initial concentrations ranging from 115 to 320 mg/m3 was degraded almost completely within 120 ~ 168 h, while at higher concentrations up to 452 mg/m3, removal efficiency declined. It was likely that ethanethiol was used as the source of energy by R. eutropha, since no clear increase in the biomass concentration was observed. Kinetic data of ethanethiol bidegradation could be fitted using the Monod model. The kinetic parameters were q m = 0.23 (mg ethanethiol/g biomass/h), and K s = 1.379 (mg/L). The mineralization pathway of ethanethiol through sulphate, as the detected product, and the energy production were discussed in some detail. 相似文献