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On the camera arts and consecutive matters : the writings of Hollis Frampton
\"As Hollis Frampton's photographs and retreated experimental films were testing the boundaries of the camera arts in the 1960s and 1970s, his provocative and highly literate writings were alternating to establish an intellectually resonate form of discourse for these critically underemplored fields. This collection of Frampton's writings presents his critical essays (many writer for Artforum and October) along with additional material, including lectures, correspondence, interviews, production notes, and scripts, it replaces - and supersedes - the long unavailable Circles of confession, published in 1983\"--Jacket.
Book
Prenatal vitamin D supplementation reduces risk of asthma/recurrent wheeze in early childhood: A combined analysis of two randomized controlled trials
We recently published two independent randomized controlled trials of vitamin D supplementation during pregnancy, both indicating a >20% reduced risk of asthma/recurrent wheeze in the offspring by 3 years of age. However, neither reached statistical significance.
To perform a combined analysis of the two trials and investigate whether maternal 25-hydroxy-vitamin D (25(OH)D) level at trial entry modified the intervention effect.
VDAART (N = 806) and COPSAC2010. (N = 581) randomized pregnant women to daily high-dose vitamin D3 (4,000 IU/d and 2,400 IU/d, respectively) or placebo. All women also received a prenatal vitamin containing 400 IU/d vitamin D3. The primary outcome was asthma/recurrent wheeze from 0-3yrs. Secondary end-points were specific IgE, total IgE, eczema and lower respiratory tract infections (LRTI). We conducted random effects combined analyses of the treatment effect, individual patient data (IPD) meta-analyses, and analyses stratified by 25(OH)D level at study entry.
The analysis showed a 25% reduced risk of asthma/recurrent wheeze at 0-3yrs: adjusted odds ratio (aOR) = 0.74 (95% CI, 0.57-0.96), p = 0.02. The effect was strongest among women with 25(OH)D level ≥30ng/ml at study entry: aOR = 0.54 (0.33-0.88), p = 0.01, whereas no significant effect was observed among women with 25(OH)D level <30ng/ml at study entry: aOR = 0.84 (0.62-1.15), p = 0.25. The IPD meta-analyses showed similar results. There was no effect on the secondary end-points.
This combined analysis shows that vitamin D supplementation during pregnancy results in a significant reduced risk of asthma/recurrent wheeze in the offspring, especially among women with 25(OH)D level ≥ 30 ng/ml at randomization, where the risk was almost halved. Future studies should examine the possibility of raising 25(OH)D levels to at least 30 ng/ml early in pregnancy or using higher doses than used in our studies.
COPSAC2010: ClinicalTrials.gov NCT00856947; VDAART: ClinicalTrials.gov NCT00920621.
Journal Article
Effectiveness of Prenatal Vitamin D Deficiency Screening and Treatment Program: A Stratified Randomized Field Trial
Abstract
Context
Despite evidence on the association between hypovitaminosis D and adverse pregnancy outcomes and the positive impact of vitamin D supplementation, no evidence exists supporting a universal screening program in pregnancy as part of routine prenatal care.
Objective
We sought to determine the effectiveness of a prenatal screening program on optimizing 25-hydroxyvitamin D [25(OH)D] levels and preventing pregnancy complications. Also, to identify a safe regimen, we compared several regimens in a subgroup of vitamin D–deficient pregnant women.
Design
Two cities of Masjed-Soleyman and Shushtar from Khuzestan province, Iran, were selected as the screening and nonscreening arms, respectively. Within the screening arm, a randomized controlled trial was conducted on 800 pregnant women.
Setting
Health centers of Masjed-Soleyman and Shushtar cities.
Patients or Participants
Pregnant women aged 18 to 40 years.
Intervention
Women with moderate [25(OH)D, 10 to 20 ng/mL] and severe [25(OH)D, <10 ng/mL] deficiency were randomly divided into four subgroups and received vitamin D3 (D3) until delivery.
Main Outcome Measure
Maternal concentration of 25(OH)D at delivery and rate of pregnancy complications
Results
After supplementation, only 2% of the women in the nonscreening site met the sufficiency level (>20 ng/mL) vs 53% of the women in the screening site. Adverse pregnancy outcomes, including preeclampsia, gestational diabetes mellitus, and preterm delivery, were decreased by 60%, 50%, and 40%, respectively, in the screening site. A D3 injection in addition to monthly 50,000 IU maintenance therapy contributed the most to achievement of sufficient levels at delivery.
Conclusions
A prenatal vitamin D screening and treatment program is an effective approach in detecting deficient women, improving 25(OH)D levels, and decreasing pregnancy adverse outcomes.
Vitamin D screening policy is beneficial in improving maternal outcomes. A high-dose vitamin D3 administration plus monthly maintenance regimen was efficient in women with baseline levels <20 ng/mL.
Journal Article
Breast cancer risk markedly lower with serum 25-hydroxyvitamin D concentrations ≥60 vs <20 ng/ml (150 vs 50 nmol/L): Pooled analysis of two randomized trials and a prospective cohort
While numerous epidemiologic studies have found an association between higher serum 25-hydroxyvitamin D [25(OH)D] concentrations and lower breast cancer risk, few have assessed this association for concentrations >40 ng/ml.
To investigate the relationship between 25(OH)D concentration and breast cancer risk across a broad range of 25(OH)D concentrations among women aged 55 years and older.
Analyses used pooled data from two randomized clinical trials (N = 1129, N = 2196) and a prospective cohort (N = 1713) to examine a broad range of 25(OH)D concentrations. The outcome was diagnosis of breast cancer during the observation periods (median: 4.0 years). Three analyses were conducted: 1) Incidence rates were compared according to 25(OH)D concentration from <20 to ≥60 ng/ml (<50 to ≥150 nmol/L), 2) Kaplan-Meier plots were developed and 3) multivariate Cox regression was used to examine the association between 25(OH)D and breast cancer risk using multiple 25(OH)D measurements.
Within the pooled cohort (N = 5038), 77 women were diagnosed with breast cancer (age-adjusted incidence: 512 cases per 100,000 person-years). Results were similar for the three analyses. First, comparing incidence rates, there was an 82% lower incidence rate of breast cancer for women with 25(OH)D concentrations ≥60 vs <20 ng/ml (Rate Ratio = 0.18, P = 0.006). Second, Kaplan-Meier curves for concentrations of <20, 20-39, 40-59 and ≥60 ng/ml were significantly different (P = 0.02), with the highest proportion breast cancer-free in the ≥60 ng/ml group (99.3%) and the lowest proportion breast cancer-free in the <20 ng/ml group (96.8%). The proportion with breast cancer was 78% lower for ≥60 vs <20 ng/ml (P = 0.02). Third, multivariate Cox regression revealed that women with 25(OH)D concentrations ≥60 ng/ml had an 80% lower risk of breast cancer than women with concentrations <20 ng/ml (HR = 0.20, P = 0.03), adjusting for age, BMI, smoking status, calcium supplement intake, and study of origin.
Higher 25(OH)D concentrations were associated with a dose-response decrease in breast cancer risk with concentrations ≥60 ng/ml being most protective.
Journal Article
Maternal 25(OH)D concentrations ≥40 ng/mL associated with 60% lower preterm birth risk among general obstetrical patients at an urban medical center
Given the high rate of preterm birth (PTB) nationwide and data from RCTs demonstrating risk reduction with vitamin D supplementation, the Medical University of South Carolina (MUSC) implemented a new standard of care for pregnant women to receive vitamin D testing and supplementation.
To determine if the reported inverse relationship between maternal 25(OH)D and PTB risk could be replicated at MUSC, an urban medical center treating a large, diverse population.
Medical record data were obtained for pregnant patients aged 18-45 years between September 2015 and December 2016. During this time, a protocol that included 25(OH)D testing at first prenatal visit with recommended follow-up testing was initiated. Free vitamin D supplements were offered and the treatment goal was ≥40 ng/mL. PTB rates (<37 weeks) were calculated, and logistic regression and locally weighted regression (LOESS) were used to explore the association between 25(OH)D and PTB. Subgroup analyses were also conducted.
Among women with a live, singleton birth and at least one 25(OH)D test during pregnancy (N = 1,064), the overall PTB rate was 13%. The LOESS curve showed gestational age rising with increasing 25(OH)D. Women with 25(OH)D ≥40 ng/mL had a 62% lower risk of PTB compared to those <20 ng/mL (p<0.0001). After adjusting for socioeconomic variables, this lower risk remained (OR = 0.41, p = 0.002). Similar decreases in PTB risk were observed for PTB subtypes (spontaneous: 58%, p = 0.02; indicated: 61%, p = 0.006), by race/ethnicity (white: 65%, p = 0.03; non-white: 68%, p = 0.008), and among women with a prior PTB (80%, p = 0.02). Among women with initial 25(OH)D <40 ng/mL, PTB rates were 60% lower for those with ≥40 vs. <40 ng/mL on a follow-up test (p = 0.006); 38% for whites (p = 0.33) and 78% for non-whites (p = 0.01).
Maternal 25(OH)D concentrations ≥40 ng/mL were associated with substantial reduction in PTB risk in a large, diverse population of women.
Journal Article
Six-Year Follow-up of a Trial of Antenatal Vitamin D for Asthma Reduction
In a previously published controlled trial, maternal administration of vitamin D during pregnancy was found to protect against wheeze in the offspring at the age of 3 years. In this follow-up study involving the same children at the age of 6 years, that supplementation no longer had a protective effect.
Journal Article
Early-Life Effects of Vitamin D: A Focus on Pregnancy and Lactation
Vitamin D is an endocrine regulator of calcium and bone metabolism. Yet, its effects include other systems, such as innate and adaptive immunity. Unique to pregnancy, circulating 1,25-dihydroxyvitamin D (1,25[OH] 2 D) increases early on to concentrations that are 2–3 times prepregnant values. At no other time during the lifecycle is the conversion of 25-hydroxyvitamin D (25[OH]D) to 1,25(OH) 2 D directly related and optimized at ≥100 nmol/L. Vitamin D deficiency appears to affect pregnancy outcomes, yet randomized controlled trials of vitamin D supplementation achieve mixed results depending on when supplementation is initiated during pregnancy, the dose and dosing interval, and the degree of deficiency at the onset of pregnancy. Analysis of trials on an intention-to-treat basis as opposed to the use of 25(OH)D as the intermediary biomarker of vitamin D metabolism yields differing results, with treatment effects often noted only in the most deficient women. Immediately after delivery, maternal circulating 1,25(OH) 2 D concentrations return to prepregnancy baseline, at a time when a breastfeeding woman has increased demands of calcium, beyond what was needed during the last trimester of pregnancy, making one question why 1,25(OH) 2 D increases so significantly during pregnancy. Is it to serve as an immune modulator? The vitamin D content of mother’s milk is directly related to maternal vitamin D status, and if a woman was deficient during pregnancy, her milk will be deficient unless she is taking higher doses of vitamin D. Because of this relative “deficiency,” there is a recommendation that all breastfed infants receive 400 IU vitamin D 3 /day starting a few days after birth. The alternative – maternal supplementation with 6,400 IU vitamin D 3 /day, effective in safely raising maternal circulating vitamin D, that of her breast milk, and effective in achieving sufficiency in her recipient breastfeeding infant – remains a viable option. Additional research is needed to understand vitamin D’s influence on pregnancy health and the effect of maternal supplementation on breast milk’s immune signaling.
Journal Article
Vitamin D supplementation and body fat mass: a systematic review and meta-analysis
Studies have indicated that 25-hydroxyvitamin D (25(OH)D) level in obese is lower than normal weight subjects; however, results of studies that investigated relationship between 25(OH)D and fat mass are inconsistent. In addition, several randomized clinical trials (RCTs) have studied the influence of cholecalciferol supplement on percentage fat mass (PFM) but their results are conflicting. The objectives were to investigate the association between vitamin D3 and PFM pooling together observational studies and RCTs. PubMed/MEDLINE, Cochrane, and Scopus were comprehensively searched from inception to September 2016. The Fisher’s Z (SE) of correlation coefficient and mean (SD) of changes in PFM from baseline were used to perform meta-analysis in observational studies and RCTs, respectively. To determine potential source of heterogeneity, subgroup and meta-regression analyses were conducted. Pooling correlation coefficients showed an inverse association between PFM (Fisher’s Z: − 0.24, 95% CI: − 0.30 to −0 .18) and FM (Fisher’s Z: − 0.32, 95% CI: − 0.43 to − 0.22) and 25(OH)D. Subgroup analysis revealed continent but not gender influence on the effect size. Meta-regression analysis indicated that age, latitude, and longitude are not sources of heterogeneity. Combining trials showed vitamin D3 supplementation had a mild but insignificant effect on PFM (− 0.31%, 95% CI: − 1.07 to 0.44). Subgroup analyses indicated that type of cholecalciferol and treatment regimens explain source of heterogeneity. Age, baseline body mass index, dose of cholecalciferol, length of study, female (%), and baseline 25(OH)D are not source of heterogeneity. In conclusion, our results state that 25(OH)D level is inversely correlated with PFM but cholecalciferol supplementation had no effect on PFM.
Journal Article
New insights into the vitamin D requirements during pregnancy
Pregnancy represents a dynamic period with physical and physiological changes in both the mother and her developing fetus. The dramatic 2-3 fold increase in the active hormone 1,25(OH)
D concentrations during the early weeks of pregnancy despite minimal increased calcium demands during that time of gestation and which are sustained throughout pregnancy in both the mother and fetus suggests an immunomodulatory role in preventing fetal rejection by the mother. While there have been numerous observational studies that support the premise of vitamin D's role in maintaining maternal and fetal well-being, until recently, there have been few randomized clinical trials with vitamin D supplementation. One has to exhibit caution, however, even with RCTs, whose results can be problematic when analyzed on an intent-to-treat basis and when there is high non-adherence to protocol (as if often the case), thereby diluting the potential good or harm of a given treatment at higher doses. As such, a biomarker of a drug or in this case \"vitamin\" or pre-prohormone is better served. For these reasons, the effect of vitamin D therapies using the biomarker circulating 25(OH)D is a far better indicator of true \"effect.\" When pregnancy outcomes are analyzed using the biomarker 25(OH)D instead of treatment dose, there are notable differences in maternal and fetal outcomes across diverse racial/ethnic groups, with improved health in those women who attain a circulating 25(OH)D concentration of at least 100 nmol·L
(40 ng·mL
). Because an important issue is the timing or initiation of vitamin D treatment/supplementation, and given the potential effect of vitamin D on placental gene expression and its effects on inflammation within the placenta, it appears crucial to start vitamin D treatment before placentation (and trophoblast invasion); however, this question remains unanswered. Additional work is needed to decipher the vitamin D requirements of pregnant women and the optimal timing of supplementation, taking into account a variety of lifestyles, body types, baseline vitamin D status, and maternal and fetal vitamin D receptor (VDR) and vitamin D binding protein (VDBP) genotypes. Determining the role of vitamin D in nonclassical, immune pathways continues to be a challenge that once answered will substantiate recommendations and public health policies.
Journal Article
The extraordinary metabolism of vitamin D
The placenta plays an important role in how vitamin D is metabolized and supplied to the fetus.
Journal Article