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American Journal of Obstetrics and... May 2023Green-stained amniotic fluid, often referred to as meconium-stained amniotic fluid, is present in 5% to 20% of patients in labor and is considered an obstetric hazard.... (Review)
Review
Green-stained amniotic fluid, often referred to as meconium-stained amniotic fluid, is present in 5% to 20% of patients in labor and is considered an obstetric hazard. The condition has been attributed to the passage of fetal colonic content (meconium), intraamniotic bleeding with the presence of heme catabolic products, or both. The frequency of green-stained amniotic fluid increases as a function of gestational age, reaching approximately 27% in post-term gestation. Green-stained amniotic fluid during labor has been associated with fetal acidemia (umbilical artery pH <7.00), neonatal respiratory distress, and seizures as well as cerebral palsy. Hypoxia is widely considered a mechanism responsible for fetal defecation and meconium-stained amniotic fluid; however, most fetuses with meconium-stained amniotic fluid do not have fetal acidemia. Intraamniotic infection/inflammation has emerged as an important factor in meconium-stained amniotic fluid in term and preterm gestations, as patients with these conditions have a higher rate of clinical chorioamnionitis and neonatal sepsis. The precise mechanisms linking intraamniotic inflammation to green-stained amniotic fluid have not been determined, but the effects of oxidative stress in heme catabolism have been implicated. Two randomized clinical trials suggest that antibiotic administration decreases the rate of clinical chorioamnionitis in patients with meconium-stained amniotic fluid. A serious complication of meconium-stained amniotic fluid is meconium aspiration syndrome. This condition develops in 5% of cases presenting with meconium-stained amniotic fluid and is a severe complication typical of term newborns. Meconium aspiration syndrome is attributed to the mechanical and chemical effects of aspirated meconium coupled with local and systemic fetal inflammation. Routine naso/oropharyngeal suctioning and tracheal intubation in cases of meconium-stained amniotic fluid have not been shown to be beneficial and are no longer recommended in obstetrical practice. A systematic review of randomized controlled trials suggested that amnioinfusion may decrease the rate of meconium aspiration syndrome. Histologic examination of the fetal membranes for meconium has been invoked in medical legal litigation to time the occurrence of fetal injury. However, inferences have been largely based on the results of in vitro experiments, and extrapolation of such findings to the clinical setting warrants caution. Fetal defecation throughout gestation appears to be a physiologic phenomenon based on ultrasound as well as in observations in animals.
Topics: Infant, Newborn; Pregnancy; Female; Humans; Meconium Aspiration Syndrome; Meconium; Amniotic Fluid; Chorioamnionitis; Pregnancy Complications; Inflammation; Heme
PubMed: 37012128
DOI: 10.1016/j.ajog.2022.11.1283 -
Experimental Biology and Medicine... Apr 2017A role for red and processed meat in the development of colorectal cancer has been proposed based largely on evidence from observational studies in humans, especially in... (Review)
Review
A role for red and processed meat in the development of colorectal cancer has been proposed based largely on evidence from observational studies in humans, especially in those populations consuming a westernized diet. Determination of causation specifically by red or processed meat is contingent upon identification of plausible mechanisms that lead to colorectal cancer. We conducted a systematic review of the available evidence to determine the availability of plausible mechanistic data linking red and processed meat consumption to colorectal cancer risk. Forty studies using animal models or cell cultures met specified inclusion criteria, most of which were designed to examine the role of heme iron or heterocyclic amines in relation to colon carcinogenesis. Most studies used levels of meat or meat components well in excess of those found in human diets. Although many of the experiments used semi-purified diets designed to mimic the nutrient loads in current westernized diets, most did not include potential biologically active protective compounds present in whole foods. Because of these limitations in the existing literature, there is currently insufficient evidence to confirm a mechanistic link between the intake of red meat as part of a healthy dietary pattern and colorectal cancer risk. Impact statement Current recommendations to reduce colon cancer include the reduction or elimination of red or processed meats. These recommendations are based on data from epidemiological studies conducted among cultures where meat consumption is elevated and consumption of fruits, vegetables, and whole grains are reduced. This review evaluated experimental data exploring the putative mechanisms whereby red or processed meats may contribute to colon cancer. Most studies used levels of meat or meat-derived compounds that were in excess of those in human diets, even in cultures where meat intake is elevated. Experiments where protective dietary compounds were used to mitigate the extreme levels of meat and meat-derived compounds showed protection against colon cancer, with some essentially negating the impact of meat in the diet. It is essential that better-designed studies be conducted that use relevant concentrations of meat or meat-derived compounds in complex diets representative of the foods consumed by humans.
Topics: Animals; Colonic Neoplasms; Cooking; Diet, Western; Heme; Humans; Iron; Meat; Mutagens; Observational Studies as Topic
PubMed: 28205448
DOI: 10.1177/1535370217693117 -
American Journal of Reproductive... Feb 2018Parturition at term is characterized by inflammatory overload in both feto-maternal tissues. Despite the large number of individual studies on changes in inflammatory... (Review)
Review
Parturition at term is characterized by inflammatory overload in both feto-maternal tissues. Despite the large number of individual studies on changes in inflammatory biomarkers linked to labor, a comprehensive profile of them in each of the uterine compartments is not available to better understand their mechanistic contributions to labor. This systematic review investigated the pro- and anti-inflammatory biomarkers reported in intra-uterine tissues (amnion, chorion, decidua, placenta, and myometrium) at term labor. We conducted a systematic review of studies on pro- and anti-inflammatory biomarkers (mRNA and/or protein) reported in feto-maternal tissues during normal human term labor, published in English (1980-2016), in 3 electronic data bases. From a total of 3712 citations, 172 were included for final review. Each tissue expresses a unique set of biomarkers at the time of term labor, but there is significant overlap between tissues. All tissues had IL-6, IL-8, IL-1β, COX-2, PGE-2, TNF-α, and hCAP18 in common at term labor. Common and unique inflammatory biomarkers are expressed in various feto-maternal compartments at term labor. Increase in pro-inflammatory markers in all gestational tissue signifies their harmonious functional role in promoting labor. Anti-inflammatory markers at term labor are hardly reported.
Topics: Animals; Antimicrobial Cationic Peptides; Biomarkers; Cathelicidins; Cyclooxygenase 2; Female; Humans; Inflammation; Inflammation Mediators; Metalloporphyrins; Parturition; Pregnancy; Uterus
PubMed: 29076197
DOI: 10.1111/aji.12776 -
PloS One 2022Heme-oxygenase 1 (HMOX1) is a critical stress response gene that catalyzes the multistep oxidation of heme. A GT(n) repeat of variable length in the promoter in has been...
INTRODUCTION
Heme-oxygenase 1 (HMOX1) is a critical stress response gene that catalyzes the multistep oxidation of heme. A GT(n) repeat of variable length in the promoter in has been associated with a wide range of human diseases, including infections. This paper aims to summarise and systematically review associations between the length of the HMOX1 GT(n) promoter and infectious disease in humans.
METHODS
A search using relevant terms was performed in PubMED and EMBASE through to 15/01/21 identifying all research that studied an association between the HMOX1 GT(n) repeat polymorphism and the incidence and/or outcome of any human infectious disease. Citations were screened for additional studies. Potential studies were screened for inclusion by two authors. Data was extracted on allele frequency, genotype, strength of association, mechanism of genotyping, and potential biases. A narrative review was performed across each type of infection.
RESULTS
1,533 studies were identified in the search, and one via citation screening. Sixteen studies were ultimately included, seven in malaria, three in HIV, three in sepsis, and one each in pneumonia, hepatitis C, and acute respiratory distress syndrome (ARDS). Sample sizes for nearly all studies were small (biggest study, n = 1,646). Allelic definition was different across all included studies. All studies were at some risk of bias. In malaria, three studies suggested that longer alleles were associated with reduced risk of severe malaria, particularly malaria-induced renal dysfunction, with four studies identifying a null association. In sepsis, two studies suggested an association with longer alleles and better outcomes.
CONCLUSIONS
Despite the importance of HMOX1 in survival from infection, and the association between repeat length and gene expression, the clinical data supporting an association between repeat length and incidence and/or outcome of infection remain inconclusive.
Topics: Communicable Diseases; Genetic Predisposition to Disease; Heme; Heme Oxygenase-1; Humans; Polymorphism, Genetic; Sepsis
PubMed: 35551540
DOI: 10.1371/journal.pone.0267399 -
BMC Cancer Jun 2019Iron has been shown to promote breast carcinogenesis in animal models through generation of oxidative stress and interaction with estrogen. Heme iron, which is found... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Iron has been shown to promote breast carcinogenesis in animal models through generation of oxidative stress and interaction with estrogen. Heme iron, which is found exclusively in animal-sourced foods, is suggested to have a more detrimental effect. Epidemiological evidence of the association between iron and breast cancer risk remains inconclusive and has not been comprehensively summarized. This systematic review and meta-analysis evaluated associations between both iron intake and body iron status and breast cancer risk.
METHODS
Four electronic databases (MEDLINE, EMBASE, CINAHL, and Scopus) were searched up to December 2018 for studies assessing iron intake and/or biomarkers of iron status in relation to breast cancer risk. Using random-effects meta-analyses, pooled relative risks (RRs) and 95% confidence intervals (CIs) were calculated comparing the highest vs. lowest category of each iron measure. Dose-response meta-analyses were also performed to investigate linear and nonlinear associations.
RESULTS
A total of 27 studies were included in the review, of which 23 were eligible for meta-analysis of one or more iron intake/status measures. Comparing the highest vs. lowest category, heme iron intake was significantly associated with increased breast cancer risk, with a pooled RR of 1.12 (95% CI: 1.04-1.22), whereas no associations were found for dietary (1.01, 95% CI: 0.89-1.15), supplemental (1.02, 95% CI: 0.91-1.13), or total (0.97, 95% CI: 0.82-1.14) iron intake. Associations of iron status indicators with breast cancer risk were generally in the positive direction; however, a significant pooled RR was found only for serum/plasma levels (highest vs. lowest) of iron (1.22, 95% CI: 1.01-1.47), but not for ferritin (1.13, 95% CI: 0.78-1.62), transferrin saturation (1.16, 95% CI: 0.91-1.47), or total iron-binding capacity (1.10, 95% CI: 0.97-1.25). In addition, a nonlinear dose-response was observed for heme iron intake and serum iron (both P < 0.05).
CONCLUSIONS
Heme iron intake and serum iron levels may be positively associated with breast cancer risk. Although associations were modest, these findings may have public health implications given the widespread consumption of (heme) iron-rich foods. In light of methodological and research gaps identified, further research is warranted to better elucidate the relationship between iron and breast cancer risk.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Breast Neoplasms; Carcinogenesis; Female; Ferritins; Heme; Humans; Iron; Iron, Dietary; Meat; Middle Aged; Nutritional Status; Postmenopause; Risk; Transferrin; Young Adult
PubMed: 31170936
DOI: 10.1186/s12885-019-5642-0 -
BMC Women's Health Aug 2018Since the publication over 50 years ago of the alkaline hematin method for quantifying menstrual blood loss (MBL) many new approaches have been developed to assess MBL....
BACKGROUND
Since the publication over 50 years ago of the alkaline hematin method for quantifying menstrual blood loss (MBL) many new approaches have been developed to assess MBL. The aim of this systematic review is to determine for methods of measuring MBL: ability to distinguish between normal and heavy menstrual bleeding (HMB); practicalities and limitations in the research setting; and suitability for diagnosing HMB in routine clinical practice.
METHODS
Embase®™, MEDLINE®, and ClinicalTrials.gov were screened for studies on the development/validation of MBL assessment methods in women with self-perceived HMB, actual HMB or uterine fibroids, or patients undergoing treatment for HMB. Studies using simulated menstrual fluid and those that included women with normal MBL as controls were also eligible for inclusion. Extracted data included study population, results of validation, and advantages/disadvantages of the technique.
RESULTS
Seventy-one studies fulfilled the inclusion criteria. The sensitivity and/or specificity of diagnosing HMB were calculated in 16 studies of methods involving self-perception of MBL (11 pictorial), and in one analysis of the menstrual-fluid-loss (MFL) method; in 13 of these studies the comparator was the gold standard alkaline hematin technique. Sensitivity and specificity values by method were, respectively: MFL model, 89, 98%; pictorial blood loss assessment chart (PBAC), 58-99%, 7.5-89%; menstrual pictogram, 82-96%, 88-94%; models/questionnaires, 59-87%, 62-86%, and complaint of HMB, 74, 74%. The power of methods to identify HMB was also assessed using other analyses such as comparison of average measurements: statistical significance was reported for the PBAC, MFL, subjective complaint, and six questionnaires. In addition, PBAC scores, menstrual pictogram volumes, MFL, pad/tampon count, iron loss, and output from three questionnaires correlated significantly with values from a reference method in at least one study. In general, pictorial methods have been more comprehensively validated than questionnaires and models.
CONCLUSIONS
Every method to assess MBL has limitations. Pictorial methods strike a good balance between ease of use and validated accuracy of MBL determination, and could complement assessment of HMB using quality of life (QoL) in the clinical and research setting.
TRIAL REGISTRATION
PRISMA registration number: CRD42016032956 .
Topics: Adult; Diagnostic Techniques, Obstetrical and Gynecological; Female; Hemin; Humans; Menorrhagia; Middle Aged; Sensitivity and Specificity; Surveys and Questionnaires
PubMed: 30134884
DOI: 10.1186/s12905-018-0627-8 -
PloS One 2022Actovegin is a hemodialysate of calf's blood and has been used for several decades in the countries of Central Asia, East Asia, Russia and some European countries. It...
BACKGROUND
Actovegin is a hemodialysate of calf's blood and has been used for several decades in the countries of Central Asia, East Asia, Russia and some European countries. It has been used to treat patients with various neurological conditions, vascular disorders, and ischemic stroke.
OBJECTIVES
To perform a systematic review to evaluate the effect of Actovegin in patients who have suffered an ischemic stroke.
METHODS
A search of MEDLINE, PubMed, Cochrane and Embase was carried out from inception to October 10, 2021 for clinical trials and observational studies with a control group, published in English or Russian.
RESULTS
Of 220 identified unique records, 84 full-text articles were screened, and 5 studies were selected that met the inclusion criteria. This included 4 observational studies with control groups and one randomized, placebo-controlled clinical trial. These studies enrolled a total of 3879 patients of which 720 patients received Actovegin administered intravenously and/or orally for a duration ranging from 10 to 180 days. Because of study heterogeneity, meta-analysis was not performed. No consistent evidence on improved survival, quality of life, neurologic symptoms, activities of daily living or disability was identified. One study showed statistically significant improvements in the Alzheimer's Disease Assessment Scale, cognitive subscale, extended version (ADAS-cog+) for Actovegin compared with placebo at 6 months but the clinical relevance of this change is uncertain. One study reported a higher incidence of recurrent ischemic stroke, transient ischemic attack or intracerebral hemorrhage in patients taking Actovegin compared to placebo.
CONCLUSIONS
The benefits of Actovegin are uncertain and that there is potential risk of harm in patients with stroke. More evidence is needed from rigorously designed clinical trials to justify the role of Actovegin in patients with ischemic stroke.
Topics: Activities of Daily Living; Heme; Humans; Ischemic Attack, Transient; Ischemic Stroke; Observational Studies as Topic; Quality of Life; Randomized Controlled Trials as Topic; Stroke
PubMed: 35771887
DOI: 10.1371/journal.pone.0270497 -
Asia Pacific Journal of Clinical... 2017Some potential role of iron overload in the development of diabetes mellitus have been suggested. Our study aimed to systematically assess the association between the... (Meta-Analysis)
Meta-Analysis
BACKGROUND AND OBJECTIVES
Some potential role of iron overload in the development of diabetes mellitus have been suggested. Our study aimed to systematically assess the association between the risk of gestational diabetes mellitus (GDM) and iron intakes/body iron status.
METHODS AND STUDY DESIGN
PubMed and Web of Science were searched for relevant articles. Relative risks (RR) of GDM in relation to dietary iron intakes and body iron stores were pooled with the random-effects model. Weighted mean differences of iron blood markers between GDM and non-GDM individuals were also analyzed.
RESULTS
Twenty-five studies were included in the qualitative analysis, and 23 studies with 29,378 participants and 3,034 GDM patients were included in the quantitative analysis. Dietary intake of heme iron was significantly associated with GDM risk (RR=1.65, 95% CI: 1.28 to 2.12), and the pooled RR for each 1mg/day increment of heme iron intake was 1.38 (95% CI: 1.19 to 1.61). No association between GDM and the intakes of nonheme iron, total iron, or supplemental iron was detected. Body iron stores, as represented by serum ferritin level, were correlated with GDM risk (RR=1.64, 95% CI: 1.27 to 2.11). Moreover, the concentrations of both serum ferritin and serum iron were increased in GDM patients, compared with non-GDM individuals.
CONCLUSIONS
Increased dietary intake of heme iron and body iron status are positively associated with the risk of GDM development in pregnant women. Future studies are warranted to better understand the role of iron in GDM development.
Topics: Diabetes, Gestational; Female; Heme; Humans; Iron, Dietary; Nutritional Status; Pregnancy
PubMed: 28917236
DOI: 10.6133/apjcn.022017.09 -
International Journal of Molecular... Apr 2020Stroke is one of the largest problems and clinical-social challenges within neurology and, in general, pathology. Here, we briefly reviewed the main pathophysiological...
BACKGROUND
Stroke is one of the largest problems and clinical-social challenges within neurology and, in general, pathology. Here, we briefly reviewed the main pathophysiological mechanisms of ischemic stroke, which represent targets for medical interventions, including for a calf blood deproteinized hemodialysate/ultrafiltrate.
METHODS
We conducted a systematic review of current related literature concerning the effects of Actovegin, of mainly the pleiotropic type, applied to the injury pathways of ischemic stroke.
RESULTS
The bibliographic resources regarding the use of Actovegin in ischemic stroke are scarce. The main Actovegin actions refer to the ischemic stroke lesion items' ensemble, targeting tissue oxidation, energy metabolism, and glucose availability through their augmentation, combating ischemic processes and oxidative stress, and decreasing inflammation (including with modulatory connotations, by the nuclear factor-κB pathway) and apoptosis-like processes, counteracting them by mitigating the caspase-3 activation induced by amyloid β-peptides.
CONCLUSION
Since no available therapeutic agents are capable of curing the central nervous system's lesions, any contribution, such as that of Actovegin (with consideration of a positive balance between benefits and risks), is worthy of further study and periodic reappraisal, including investigation into further connected aspects.
Topics: Amyloid beta-Peptides; Animals; Antioxidants; Brain Ischemia; Heme; Humans; Stroke
PubMed: 32365943
DOI: 10.3390/ijms21093181