Differences in Polyamine Content between Human Milk and Infant Formulas

Human milk is the gold standard for nutrition during the first months of life, but when breastfeeding is not possible, it may be replaced by infant formulas, either partially or totally. Polyamines, which play an important role in intestinal maturation and the development of the immune system, are found both in human milk and infant formulas, the first exogenous source of these compounds for the newborn. The aim of this study was to evaluate the occurrence and evolution of polyamines in human milk during the first semester of lactation and to compare the polyamine content with that of infant formulas. In total, 30 samples of human milk provided by six mothers during the first five months of lactation as well as 15 different types of infant formulas were analyzed using UHPLC-FL. Polyamines were detected in all human milk samples but with great variation among mothers. Spermidine and spermine levels tended to decrease during the lactation period, while putrescine remained practically unchanged. Considerable differences were observed in the polyamine contents and profiles between human milk and infant formulas, with concentrations being up to 30 times lower in the latter. The predominant polyamines in human milk were spermidine and spermine, and putrescine in infant formulas.

Influence of Breastfeeding Factors on Polyamine Content in Human Milk

The polyamine content of human breast milk, which is the first exogenous source of polyamines for the newborn, can be affected by several factors associated with the mother, the infant, or breastfeeding itself. The aim of this study was to evaluate the influence of different breastfeeding factors on the polyamines found in human milk. For this study, a cohort of 83 mothers was considered for up to 4 months, and a subgroup of 33 mothers were followed during the first six months of breastfeeding. Two breast milk samples were collected at each sampling point (foremilk and hindmilk) and the polyamine content was determined by UHPLC-FL. Polyamine levels varied considerably between the mothers and tended to decrease over time. Putrescine was the minor polyamine, whereas spermidine and spermine contents were very similar. The concentrations of the three polyamines were significantly higher in hindmilk than foremilk (p < 0.001). Spermidine and spermine levels decreased significantly through the lactation progress (p < 0.05). Finally, slightly higher levels of polyamines were observed in the milk of mothers providing partial, rather than full, breastfeeding, although the differences were not significant. The polyamine content in human milk was found to change during a single feed (foremilk versus hindmilk) and as lactation progressed, mainly in response to the specific circumstances of the newborn.

Midwives and Maternal Mortality Evidence from a Midwifery Policy Experiment in 19th Century Sweden

This paper estimates the causal effect of a historical midwifery policy experiment on maternal mortality, infant mortality, and stillbirth during the period of 1830–1894 in Sweden. Exploiting sharp changes or “discontinuities” across time and place in the availability of trained and licensed midwives as an exogenous source of variation, we find that a doubling of trained midwives led to a 20%–40% reduction in maternal mortality and a 20% increase in the uptake of midwife-assisted homebirths. The results thus suggest that a 1% increase in the share of midwife-assisted homebirths decreased maternal mortality by as much as 2%, which is a remarkable finding given that midwife training was only 6–12 months at that time. The results of this study contribute to the current debate about the most effective strategy to reduce the unacceptably high rate of maternal mortality in many developing countries, especially in low-resource settings.

Application of P4 rapid test and exogenous source of progesterone in prevention of early embryonic death in dairy cows

The objectives of this study were: 1) to determine the percent of cows with low P4 at Day 7-8 post-AI; 2) to treat the animal with low progesterone for 14 days with a P4-releasing intravaginal device (PRID DELTA); 3) to analyze the influence of P4 exogenous supplementation on pregnancy rate in treated and non-treated cows and 4) to create a protocol using “P4 Rapid” test allowing increased pregnancy rate under farm conditions. For this purpose, the current study has been conducted on 155 repeat breeding Holstein cows (<3 artificially inseminated – AI) with prolonged estrus cycle (<26 days). At day 7 and 8 post-AI, the milk progesterone levels were measured (P4 Rapid test). The cows with low P4 (n=104 or 67%) were divided into two groups each n=52. In Group I the progesterone devices were inserted for two weeks and control Group II without progesterone devices. At days 40 and 50 post artificial insemination (AI) all animals (n=104) were submitted to ultrasound pregnancy detection. Pregnancy was registered in 27 animals (51.9%) for Group 1, and in 16 cows (30.7%) for Group II. P4 Rapid is a quick, easy and practically applicable test to measure milk progesterone levels in dairy farms. The method is highly accurate and detects animals with low or high P4 at Day 7-8 after insemination. It also allows identification of conditions such as ovarian cysts, ovarian hypofunction and distinguishing of cycling and non-cycling cows. The combination of P4 measurement by P4 Rapid test and treatment with exogenous P4 to increase circulating concentrations in the first few days after conception can prevent embryo death and improve reproductive efficiency in dairy cattle.

A cysteine-triggered fluorogenic donor base on native chemical ligation for tracking H2S delivery in vivo

Hydrogen sulfide (H2S) donor is a fundamental molecular tool used as the exogenous source in related biological studies and therapies. However, controllable and fluorescence visual H2S donor is still lack....

Diversity and Conflict

This research advances the hypothesis and establishes empirically that interpersonal population diversity, rather than fractionalization or polarization across ethnic groups, has been pivotal to the emergence, prevalence, recurrence, and severity of intrasocietal conflicts. Exploiting an exogenous source of variations in population diversity across nations and ethnic groups, as determined predominantly during the exodus of humans from Africa tens of thousands of years ago, the study demonstrates that population diversity, and its impact on the degree of diversity within ethnic groups, has contributed significantly to the risk and intensity of historical and contemporary civil conflicts. The findings arguably reflect the contribution of population diversity to the non‐cohesiveness of society, as reflected partly in the prevalence of mistrust, the divergence in preferences for public goods and redistributive policies, and the degree of fractionalization and polarization across ethnic, linguistic, and religious groups.

Do Fiscal Rules Cause Fiscal Discipline Over the Electoral Cycle?

This paper estimates the causal effect of fiscal rules on political budget cycles in a sample of 67 developing countries over the period 1985–2007. We exploit the geographical pattern in the adoption of fiscal rules to isolate an exogenous source of variation in the adoption of national fiscal rules. Based on a diffusion argument, we use the number of other countries in a given subregion that have fiscal rules in place to predict the probability of having them at the country level. We find that in election years with fiscal rules in place, public consumption is reduced by 1.6 percentage point of GDP as compared to election years without these rules. This impact is equivalent to a reduction by a third of the volatility of public consumption in our sample. Furthermore, the effectiveness of these rules depends on their type, their institutional design, whether they have been in place for a long time and finally on the degree of competitiveness of elections.

Colon Tumor Tattooing-Derived Ink-Laden Macrophages in Peritoneal Ascitic Fluid

Introduction: Macrophages containing exogenous pigments are commonly encountered in cytological specimens. Case Presentation: We present a case of tumor tattooing as an infrequent exogenous source of peritoneal fluid macrophagic pigment in a 76-year-old female. Discussion and Conclusion: Tattooing-derived ink can be a source of macrophagic pigment and should not be confused with other endogenous or exogenous pigments. The anatomical location and past medical history of the patient can aid in the diagnosis.