797 research outputs found
Probiotics to prevent infantile colic
Background
Infantile colic is typically defined as fullâforce crying for at least three hours per day, on at least three days per week, for at least three weeks. Infantile colic affects a large number of infants and their families worldwide. Its symptoms are broad and general, and while not indicative of disease, may represent a serious underlying condition in a small percentage of infants who may need a medical assessment. Probiotics are live microorganisms that alter the microflora of the host and provide beneficial health effects. The most common probiotics used are of Lactobacillus, Bifidobacterium and Streptococcus. There is growing evidence to suggest that intestinal flora in colicky infants differ from those in healthy infants, and it is suggested that probiotics can redress this balance and provide a healthier intestinal microbiota landscape. The low cost and easy availability of probiotics makes them a potential prophylactic solution to reduce the incidence and prevalence of infantile colic.
Objectives
To evaluate the efficacy and safety of prophylactic probiotics in preventing or reducing severity of infantile colic.
Search methods
In January 2018 we searched CENTRAL, MEDLINE, Embase, PsycINFO, CINAHL, 10 other databases and two trials registers. In addition, we handsearched the abstracts of relevant meetings, searched reference lists, ran citation searches of included studies, and contacted authors and experts in the field, including the manufacturers of probiotics, to identify unpublished trials.
Selection criteria
Randomised control trials (RCTs) of newborn infants less than one month of age without the diagnosis of infantile colic at recruitment. We included any probiotic, alone or in combination with a prebiotic (also known as synbiotics), versus no intervention, another intervention(s) or placebo, where the focus of the study was the effect of the intervention on infantile colic.
Data collection and analysis
We used standard methodological procedures of Cochrane.
Main results
Our search yielded 3284 records, and of these, we selected 21 reports for fullâtext review. Six studies with 1886 participants met our inclusion criteria, comparing probiotics with placebo. Two studies examined Lactobacillus reuteri DSM, two examined multiâstrain probiotics, one examined Lactobacillus rhamnosus, and one examined Lactobacillus paracasei and Bifidobacterium animalis. Two studies began probiotics during pregnancy and continued administering them to the baby after birth.
We considered the risk of bias for randomisation as low for all six trials; for allocation concealment as low in two studies and unclear in four others. All studies were blinded, and at low risk of attrition and reporting bias.
A randomâeffects metaâanalysis of three studies (1148 participants) found no difference between the groups in relation to occurrence of new cases of colic: risk ratio (RR) 0.46, 95% confidence interval (CI) 0.18 to 1.19; lowâcertainty evidence; I2 = 72%.
A randomâeffects metaâanalysis of all six studies (1851 participants) found no difference between the groups in relation to serious adverse effects (RR 1.02, 95% CI 0.14 to 7.21; lowâcertainty evidence; I2 not calculable (only four serious events for one comparison, two in each group: meconium plug obstruction, patent ductus arteriosus and neonatal hepatitis).
A randomâeffects metaâanalysis of three studies (707 participants) found a mean difference (MD) of â32.57 minutes per day (95% CI â55.60 to â9.54; lowâcertainty evidence; I2 = 93%) in crying time at study end in favour of probiotics.
A subgroup analysis of the most studied agent, Lactobacillus reuteri, showed a reduction of 44.26 minutes in daily crying with a randomâeffects model (95% CI â66.6 to â21.9; I2 = 92%), in favour of probiotics.
Authors' conclusions
There is no clear evidence that probiotics are more effective than placebo at preventing infantile colic; however, daily crying time appeared to reduce with probiotic use compared to placebo. There were no clear differences in adverse effects.
We are limited in our ability to draw conclusions by the certainty of the evidence, which we assessed as being low across all three outcomes, meaning that we are not confident that these results would not change with the addition of further researc
Parent training programmes for managing infantile colic
Background
Infantile colic has an effect on both infants and their parents, who become exhausted and concerned as they attempt to comfort their child. Common approaches have focused upon physical treatments to reduce symptoms, with inconclusive evidence as to their effectiveness. An alternative approach seeks to provide training, support and psychological interventions for parents. This approach is known as parent training programmes. Programmes can include soothing techniques, advice on feeding or normalisation material in any form. The teaching format can vary including faceâtoâface courses, online learning, printed materials, home visits and remote support and counselling. Here, we aim to collate the evidence on the effectiveness of these interventions and examine their effectiveness at reducing infantile colic symptoms and parental anxiety levels, and their safety.
Objectives
1. To evaluate the effectiveness and safety of parent training programmes for managing colic in infants under four months of age.
2. To identify the educational content and attributes of such published programmes.
Search methods
In June 2019 we searched CENTRAL, MEDLINE, Embase, 13 other databases and two trials registers. We also handsearched conference abstracts, inspected the references of included studies and contacted leaders in the field for more trials.
Selection criteria
Randomised controlled trials (RCTs) and quasiâRCTs investigating the effectiveness of any form of parental training programmes, alone or in combination, versus another intervention(s) or control, on infantile colic.
Data collection and analysis
Two authors independently selected studies for inclusion, extracted data, and assessed the risk of bias within the included studies. We used Review Manager 5 to analyse the data. We assessed the certainty of the evidence using GRADE methodology
The effect of TiO2 coatings on the formation of ozone and nitrogen oxides in non-thermal atmospheric pressure plasma
The use of photocatalytic materials in plasma systems has the potential to enhance the selectivity and yield of desired products. However, the surface interaction between the photocatalyst and plasma is a complex process that is not well understood. This work presents a comprehensive study of the effects of combining titanium dioxide (TiO2) photocatalysts with non-thermal atmospheric pressure nitrogen-oxygen plasmas, which increases the production of ozone and dinitrogen pentoxide (N2O5) while limiting the formation of harmful nitrogen dioxide (NO2) and nitrous oxide (N2O) by products. TiO2 coatings were deposited by magnetron sputtering onto barium titanate (BaTiO3) particulates for use within a packed bed dielectric barrier discharge reactor (DBD). The presence of titanium dioxide can affect the plasma chemistry in the DBD by acting as a sink for atomic oxygen, through photocatalytic formation of superoxide anion radical (O2-), and alteration of the dielectric constant of the BaTiO3 particulates. This work explains the complex interaction of these effects on oxygen and nitrogen plasma chemistry. The effect of the photocatalyst surface properties, gas composition and residence time on the reaction pathways for the formation of ozone and nitrogen oxides (NxOy) were investigated. The photocatalytic activity of titanium dioxide was improved by annealing the coated surface, and was subsequently found to enable the formation of ozone, increase the formation of N2O5 while significantly decreasing the formation of harmful NO2 and N2O with a residence time of 0.011
The population genetic structure of the urchin Centrostephanus rodgersii in New Zealand with links to Australia
Š The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2021Publishe
The Effects of Wildfire on Mortality and Resources for an Arboreal Marsupial: Resilience to Fire Events but Susceptibility to Fire Regime Change
BACKGROUND: Big environmental disturbances have big ecological effects, yet these are not always what we might expect. Understanding the proximate effects of major disturbances, such as severe wildfires, on individuals, populations and habitats will be essential for understanding how predicted future increases in the frequency of such disturbances will affect ecosystems. However, researchers rarely have access to data from immediately before and after such events. Here we report on the effects of a severe and extensive forest wildfire on mortality, reproductive output and availability of key shelter resources for an arboreal marsupial. We also investigated the behavioural response of individuals to changed shelter resource availability in the post-fire environment. METHODOLOGY/PRINCIPAL FINDINGS: We fitted proximity-logging radiotransmitters to mountain brushtail possums (Trichosurus cunninghami) before, during and after the 2009 wildfires in Victoria, Australia. Surprisingly, we detected no mortality associated with the fire, and despite a significant post-fire decrease in the proportion of females carrying pouch young in the burnt area, there was no short-term post-fire population decline. The major consequence of this fire for mountain brushtail possums was the loss of over 80% of hollow-bearing trees. The types of trees preferred as shelter sites (highly decayed dead standing trees) were those most likely to collapse after fire. Individuals adapted to resource decline by being more flexible in resource selection after the fire, but not by increased resource sharing. CONCLUSIONS/SIGNIFICANCE: Despite short-term demographic resilience and behavioural adaptation following this fire, the major loss of decayed hollow trees suggests the increased frequency of stand-replacing wildfires predicted under climate change will pose major challenges for shelter resource availability for hollow-dependent fauna. Hollow-bearing trees are typically biological legacies of previous forest generations in post-fire regrowth forests but will cease to be recruited to future regrowth forests if the interval between severe fires becomes too rapid for hollow formation
Dietary modifications for infantile colic
Background
Infantile colic is typically defined as fullâforce crying for at least three hours per day, on at least three days per week, for at least three weeks. This condition appears to be more frequent in the first six weeks of life (prevalence range of 17% to 25%), depending on the specific location reported and definitions used, and it usually resolves by three months of age. The aetiopathogenesis of infantile colic is unclear but most likely multifactorial. A number of psychological, behavioural and biological components (food hypersensitivity, allergy or both; gut microflora and dysmotility) are thought to contribute to its manifestation. The role of diet as a component in infantile colic remains controversial.
Objectives
To assess the effects of dietary modifications for reducing colic in infants less than four months of age.
Search methods
In July 2018 we searched CENTRAL, MEDLINE, Embase , 17 other databases and 2 trials registers. We also searched Google, checked and handsearched references and contacted study authors.
Selection criteria
Randomised controlled trials (RCTs) and quasiâRCTs evaluating the effects of dietary modifications, alone or in combination, for colicky infants younger than four months of age versus another intervention or placebo. We used specific definitions for colic, age of onset and the methods for performing the intervention. We defined 'modified diet' as any diet altered to include or exclude certain components.
Data collection and analysis
We used standard methodological procedures expected by Cochrane. Our primary outcome was duration of crying, and secondary outcomes were response to intervention, frequency of crying episodes, parental/family quality of life, infant sleep duration, parental satisfaction and adverse effects.
Main results
We included 15 RCTs involving 1121 infants (balanced numbers of boys and girls) aged 2 to 16 weeks. All studies were small and at high risk of bias across multiple design factors (e.g. selection, attrition). The studies covered a wide range of dietary interventions, and there was limited scope for metaâanalysis. Using the GRADE approach, we assessed the quality of the evidence as very low.
Lowâallergen maternal diet versus a diet containing known potential allergens: one study (90 infants) found that 35/47 (74%) of infants responded to a lowâallergen maternal diet, compared with 16/43 (37%) of infants on a diet containing known potential allergens.
Lowâallergen diet or soy milk formula versus dicyclomine hydrochloride: one study (120 infants) found that 10/15 (66.6%) breastfed babies responded to dicyclomine hydrochloride, compared with 24/45 (53.3%) formulaâfed babies. There was little difference in response between breastfed babies whose mother changed their diet (10/16; 62.5%) and babies who received soy milk formula (29/44; 65.9%).
Hydrolysed formula versus standard formula: two studies (64 infants) found no difference in duration of crying, reported as a dichotomous outcome: risk ratio 2.03, 95% confidence interval (CI) 0.81 to 5.10; very lowâquality evidence. The author of one study confirmed there were no adverse effects. One study (43 infants) reported a greater reduction in crying time postintervention with hydrolysed formula (104 min/d, 95% CI 55 to 155) than with standard formula (3 min/d, 95% CI â63 to 67).
Hydrolysed formula versus another hydrolysed formula: one study (22 infants) found that two types of hydrolysed formula were equally effective in resolving symptoms for babies who commenced with standard formula (Alimentum reduced crying to 2.21 h/d (standard deviation (SD) 0.40) and Nutramigen to 2.93 h/d (SD 0.70)).
Hydrolysed formula or dairyâ and soyâfree maternal diet versus addition of parental education or counselling: one study (21 infants) found that crying time decreased to 2.03 h/d (SD 1.03) in the hydrolysed or dairyâ and soyâfree group compared with 1.08 h/d (SD 0.7) in the parent education or counselling group, nine days into the intervention.
Partially hydrolysed, lower lactose, wheyâbased formulae containing oligosaccharide versus standard formula with simethicone: one study (267 infants) found that both groups experienced a decrease in colic episodes (secondary outcome) after seven days (partially hydrolysed formula: from 5.99 episodes (SD 1.84) to 2.47 episodes (SD 1.94); standard formula: from 5.41 episodes (SD 1.88) to 3.72 episodes (SD 1.98)). After two weeks the difference between the two groups was significant (partially hydrolysed: 1.76 episodes (SD 1.60); standard formula: 3.32 episodes (SD 2.06)). The study author confirmed there were no adverse effects.
Lactase enzyme supplementation versus placebo: three studies (138 infants) assessed this comparison, but none reported data amenable to analysis for any outcome. There were no adverse effects in any of the studies.
Extract of Foeniculum vulgare, Matricariae recutita, and Melissa officinalis versus placebo: one study (93 infants) found that average daily crying time was lower for infants given the extract (76.9 min/d (SD 23.5), than infants given placebo (169.9 min/d (SD 23.1), at the end of the oneâweek study. There were no adverse effects.
Soy proteinâbased formula versus standard cows' milk proteinâbased formula: one study (19 infants) reported a mean crying time of 12.7 h/week (SD 16.4) in the soy formula group versus 17.3 h/week (SD 6.9) in the standard cows' milk group, and that 5/10 (50%) responded in the soy formula group versus 0/9 (0%) in the standard cows' milk group.
Soy protein formula with polysaccharide versus standard soy protein formula: one study (27 infants) assessed this comparison but did not provide disaggregated data for the number of responders in each group after treatment.
No study reported on our secondary outcomes of parental or family quality of life, infant sleep duration per 24 h, or parental satisfaction
Gravity waves and the LHC: Towards high-scale inflation with low-energy SUSY
It has been argued that rather generic features of string-inspired
inflationary theories with low-energy supersymmetry (SUSY) make it difficult to
achieve inflation with a Hubble scale H > m_{3/2}, where m_{3/2} is the
gravitino mass in the SUSY-breaking vacuum state. We present a class of
string-inspired supergravity realizations of chaotic inflation where a simple,
dynamical mechanism yields hierarchically small scales of post-inflationary
supersymmetry breaking. Within these toy models we can easily achieve small
ratios between m_{3/2} and the Hubble scale of inflation. This is possible
because the expectation value of the superpotential relaxes from large to
small values during the course of inflation. However, our toy models do not
provide a reasonable fit to cosmological data if one sets the SUSY-breaking
scale to m_{3/2} < TeV. Our work is a small step towards relieving the apparent
tension between high-scale inflation and low-scale supersymmetry breaking in
string compactifications.Comment: 21+1 pages, 5 figures, LaTeX, v2: added references, v3: very minor
changes, version to appear in JHE
Aidnogenesis via Leptogenesis and Dark Sphalerons
We discuss aidnogenesis, the generation of a dark matter asymmetry via new
sphaleron processes associated to an extra non-abelian gauge symmetry common to
both the visible and the dark sectors. Such a theory can naturally produce an
abundance of asymmetric dark matter which is of the same size as the lepton and
baryon asymmetries, as suggested by the similar sizes of the observed baryonic
and dark matter energy content, and provide a definite prediction for the mass
of the dark matter particle. We discuss in detail a minimal realization in
which the Standard Model is only extended by dark matter fermions which form
"dark baryons" through an SU(3) interaction, and a (broken) horizontal symmetry
that induces the new sphalerons. The dark matter mass is predicted to be
approximately 6 GeV, close to the region favored by DAMA and CoGeNT.
Furthermore, a remnant of the horizontal symmetry should be broken at a lower
scale and can also explain the Tevatron dimuon anomaly.Comment: Minor changes, discussion of present constraints expanded. 16 pages,
2 eps figures, REVTeX
Evolutionary explanations in medical and health profession courses: are you answering your students' "why" questions?
BACKGROUND: Medical and pre-professional health students ask questions about human health that can be answered in two ways, by giving proximate and evolutionary explanations. Proximate explanations, most common in textbooks and classes, describe the immediate scientifically known biological mechanisms of anatomical characteristics or physiological processes. These explanations are necessary but insufficient. They can be complemented with evolutionary explanations that describe the evolutionary processes and principles that have resulted in human biology we study today. The main goal of the science of Darwinian Medicine is to investigate human disease, disorders, and medical complications from an evolutionary perspective. DISCUSSION: This paper contrasts the differences between these two types of explanations by describing principles of natural selection that underlie medical questions. Thus, why is human birth complicated? Why does sickle cell anemia exist? Why do we show symptoms like fever, diarrhea, and coughing when we have infection? Why do we suffer from ubiquitous age-related diseases like arteriosclerosis, Alzheimer's and others? Why are chronic diseases like type II diabetes and obesity so prevalent in modern society? Why hasn't natural selection eliminated the genes that cause common genetic diseases like hemochromatosis, cystic fibrosis, Tay sachs, PKU and others? SUMMARY: In giving students evolutionary explanations professors should underscore principles of natural selection, since these can be generalized for the analysis of many medical questions. From a research perspective, natural selection seems central to leading hypotheses of obesity and type II diabetes and might very well explain the occurrence of certain common genetic diseases like cystic fibrosis, hemochromatosis, Tay sachs, Fragile X syndrome, G6PD and others because of their compensating advantages. Furthermore, armed with evolutionary explanations, health care professionals can bring practical benefits to patients by treating their symptoms of infection more specifically and judiciously. They might also help curtail the evolutionary arms race between pathogens and antibiotic defenses
Reexamining the possible benefits of visual crowding: dissociating crowding from ensemble percepts
Peripheral objects and their features become indistinct when closely surrounding but nonoverlapping objects are present. Most models suggest that this phenomenon, called crowding, reflects limitations of visual processing, but an intriguing idea is that it may be, in part, adaptive. Specifically, the mechanism generating crowding may simultaneously facilitate ensemble representations of features, leaving meaningful information about clusters of objects. In two experiments, we tested whether visual crowding and the perception of ensemble features share a common mechanism. Observers judged the orientation of a crowded bar, or the ensemble orientation of all bars in the upper and lower visual fields. While crowding was predictably stronger in the upper relative to the lower visual field, the ensemble percept did not vary between the visual fields. Featural averaging within the crowded region does not always scale with the resolution limit defined by crowding, suggesting that dissociable processes contribute to visual crowding and ensemble percepts
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