OBJECTIVES: To study the influence of umbilical cord milking versus delayed cord clamping on the early prognosis of preterm infants with a gestational age of <34 weeks. METHODS: PubMed, Web of Science, Embase, the Cochrane Library, CINAHL, China National Knowledge Infrastructure, Wanfang Data, Weipu Database, and SinoMed were searched for randomized controlled trials on umbilical cord milking versus delayed cord clamping in preterm infants with a gestational age of <34 weeks published up to November 2021. According to the inclusion and exclusion criteria, two researchers independently performed literature screening, quality evaluation, and data extraction. Review Manger 5.4 was used for Meta analysis. RESULTS: A total of 11 articles were included in the analysis, with 1 621 preterm infants in total, among whom there were 809 infants in the umbilical cord milking group and 812 in the delayed cord clamping group. The Meta analysis showed that compared with delayed cord clamping, umbilical cord milking increased the mean blood pressure after birth (weighted mean difference=3.61, 95%CI: 0.73-6.50, P=0.01), but it also increased the incidence rate of severe intraventricular hemorrhage (RR=1.83, 95%CI: 1.08-3.09, P=0.02). There were no significant differences between the two groups in hemoglobin, hematocrit, blood transfusion rate, proportion of infants undergoing phototherapy, bilirubin peak, and incidence rates of complications such as periventricular leukomalacia and necrotizing enterocolitis (P>0.05). CONCLUSIONS Compared with delayed cord clamping, umbilical cord milking may increase the risk of severe intraventricular hemorrhage in preterm infants with a gestational age of <34 weeks; however, more high-quality large-sample randomized controlled trials are needed for further confirmation.
Cerebral Hemorrhage ; Constriction ; Female ; Gestational Age ; Humans ; Infant ; Infant, Newborn ; Infant, Premature ; Pregnancy ; Prognosis ; Umbilical Cord/physiology* ; Umbilical Cord Clamping

INTRODUCTION: Umbilical cord milking (UCM) is a method that allows for postnatal placental transfusion. The benefits of UCM have been demonstrated in some studies, but knowledge about its haemodynamic effects in term infants is limited. The aim of this study was to evaluate the haemodynamic effects of UCM in term infants. METHODS: In this prospective, randomised controlled study, 149 healthy term infants with a birth week of ≥37 weeks were randomly assigned to either the UCM or immediate cord clamping (ICC) group. Blinded echocardiographic evaluations were performed in all the neonates in the first 2-6 h. RESULTS: Superior vena cava (SVC) flow measurements were higher in the UCM group compared to the ICC group (132.47 ± 37.0 vs. 126.62 ± 34.3 mL/kg/min), but this difference was not statistically significant. Left atrial diameter (12.23 ± 1.99 vs. 11.43 ± 1.78 mm) and left atrium-to-aorta diastolic diameter ratio (1.62 ± 0.24 vs. 1.51 ± 0.22) were significantly higher in the UCM group. There were no significant differences in other echocardiographic parameters between the two groups. CONCLUSION We found no significant difference in the SVC flow measurements in term infants who underwent UCM versus those who underwent ICC. This lack of significant difference in SVC flow may be explained by the mature cerebral autoregulation mechanism in term neonates.
Infant, Newborn ; Infant ; Humans ; Pregnancy ; Female ; Infant, Premature/physiology* ; Umbilical Cord Clamping ; Prospective Studies ; Vena Cava, Superior/diagnostic imaging* ; Placenta ; Umbilical Cord/physiology* ; Constriction ; Hemodynamics/physiology*

OBJECTIVEThis literature review aims to summarize the methods of isolation, expansion, differentiation and preservation of human umbilical cord mesenchymal stem cells (hUCMSCs), for comprehensive understanding and practical use in preclinical research and clinical trials.

DATA SOURCESAll the literature reviewed was published over the last 10 years and is listed in PubMed and Chinese National Knowledge Infrastructure (CNKI). Studies were retrieved using the key word "human umbilical cord mesenchymal stem cells".

RESULTSExplants culture and enzymatic digestion are two methods to isolate hUCMSCs from WJ and there are modifications to improve these methods. Culture conditions may affect the expansion and differentiating orientations of hUCMSCs. In addition, hUCMSCs can maintain their multi-potential effects after being properly frozen and thawed.

CONCLUSIONConsidering their multi-potential, convenient and non-invasive accessibility, low immunogenicity and the reported therapeutic effects in several different preclinical animal models, hUCMSCs have immense scope in regeneration medicine as a substitute for MSCs derived from bone marrow or umbilical cord blood.

Cell Culture Techniques ; methods ; Cell Differentiation ; physiology ; Humans ; Mesenchymal Stromal Cells ; cytology ; Umbilical Cord ; cytology

Recent progress in stem cell research is opening a new hope for cell therapy in regenerative medicine. Two breakthroughs were made in the stem cell era, one, new discoveries in multipotentiality of adult stem cells beyond the traditionally appreciated extent, and the other, establishment of pluripotent stem cell from human embryo. In addition to the newly identified multipotentiality of adult stem cells, their ability to be trans-differentiated toward other tissue types (stem cell plasticity) as well as to migrate toward the site of tissue damage make adult stem cells particularly attractive choice for stem cell based therapy. Stem cell therapy for organ regeneration, therefore, could be approached from three distinct dimensions: first, direct differentiation of multi-potent stem cells toward desired tissue types; secondly, regeneration of specific tissues through in vivo stem cell plasticity, and lastly, by tissue-specific stem cells from many types of organs. While each approach in stem cell therapy poses distinctive limitations for their success-ful clinical applications, understanding regulatory mechanisms of stem cell selfrenewal and their in vivo engraftment will mostly extend their medical efficacy of stem cell based therapy.
Animals ; *Hematopoietic Stem Cell Transplantation ; Humans ; Stem Cells/*physiology ; Umbilical Cord

OBJECTIVETo review the recent studies about human umbilical cord mesenchymal stem cells (hUCMSCs) and advances in the treatment of spinal cord injury. Data sources Published articles (1983 - 2007) about hUCMSCs and spinal cord injury were selected using Medline. Study selection Articles selected were relevant to development of mesenchymal stem cells (MSCs) for transplantation in spinal cord injury therapy. Of 258 originally identified articles 51 were selected that specifically addressed the stated purpose.

RESULTSRecent work has revealed that hUCMSCs share most of the characteristics with MSCs derived from bone marrow and are more appropriate to transplantation for cell based therapies.

CONCLUSIONSHuman umbilical cord could be regarded as a source of MSCs for experimental and clinical needs. In addition, as a peculiar source of stem cells, hUCMSCs may play an important role in the treatment of spinal cord injury.

Humans ; Mesenchymal Stromal Cells ; cytology ; physiology ; Models, Biological ; Spinal Cord Injuries ; pathology ; therapy ; Stem Cell Transplantation ; Umbilical Cord ; cytology

This study was purposed to compare the biological characteristics of umbilical cord-derived mesenchymal stem cells (UC-MSCs) and bone marrow-derived mesenchymal stem cells (BM-MSCs). The frequency of successful isolation, cell yield, colony-forming units-fibroblastics (CFU-F), proliferation capacity, immunophenotype and multi-differentiation potentials of UC-MSCs and BM-MSCs were determined by limiting dilution assay, flow cytometry, invert microscopy, RT-PCR and so on, the determined results were compared. The results showed that MSCs were successfully isolated from all the 36 portion of UC tissue and 8 portion of BM. Although the mean number of nucleated cells isolated from UC tissue was significantly lower than that from BMs (1 x 10(6)/cm vs 5.5 x 10(7)/ml) (p=0.0002), no significant differences of the yield of adherent cells were observed (8.6 x 10(5)/cm vs 8.4 x 10(5)/ml) (p>0.05). UC-MSCs shared the most of the characteristic of BM-MSC, including fibroblastic-like morphology, typical immunophenotype, cell cycle status, adipogenic and osteogenic differentiation potentials. However, the CFU-F frequency was higher in UC (1:1609+/-0.18) than that in BM (1:35700+/-0.01) (p<0.05). Furthermore, the proliferation capacity of UC-MSCs was higher than that of BM-MSCs; the expressions of CD106 and HLA-class I in UC-MSCs were lower than those in BM-MSCs (p<0.05). It is concluded that the cell yield and most biological characteristics of UC-MSCs are similar to BM-MSCs, but UC-MSCs possess the higher proliferation capacity, and the lower expression of HLA-class I and HLA-DR as compared with BM-MSCs, therefore the human umbilical cord tissue may be considered as a promising alternative to bone marrow as a source of MSCs.
Bone Marrow Cells ; cytology ; physiology ; Cell Differentiation ; Cells, Cultured ; Humans ; Mesenchymal Stromal Cells ; cytology ; physiology ; Organ Specificity ; physiology ; Umbilical Cord ; cytology ; physiology

OBJECTIVE: To investigate the effect of Piwil2-induced cancer stem-like cell (Piwil2-iCSC)-derived exosomes on the proliferation,migration and invasion of human umbilical cord blood-derived mesenchymal stem cells (hucMSCs). METHODS: Piwil2-iCSC-derived exosomes were isolated by ultracentrifugation and identified using transmission electron microscopy,nanoparticle tracking analysis and Western blotting.Exosome uptake assay was used to identify the pathway that Piwil2-iCSCderived exosomes utilized.HucMSCs were divided into control group,PBS intervention group and exosome intervention group,and CCK-8 assay,wound healing assay,Transwell assay,Western blotting and cell karyotype analysis were used to observe the proliferation,migration,invasion,expression levels of MMP2 and MMP9 proteins,and chromosome structure of hucMSCs. RESULTS: The diameter of Piwil2-iCSC-derived exosomes ranged from 50 nm to 100 nm,and most of them were oval or spherical capsules rich in CD9,CD63 and Piwil2 proteins.Exosomal uptake assay showed that the exosomes executed theirs functions after entering the cells.Compared with the control cells and PBS-treated cells,hucMSCs treated with the exosomes showed significantly increased number of proliferating cells (<0.05) with accelerated healing rate (<0.05 at 24 h;<0.01 at 48 h),increased invasive cells (<0.01),enhanced protein expressions of MMP2(<0.05 PBS group;<0.01 control group) and MMP9(<0.05),but their karyotype still remained 46XY without any abnormalities. CONCLUSIONS Piwil2-iCSC-derived exosomes can promote the proliferation,migration and invasion but does not cause cancer-like heterogeneity changes in hucMSCs.
Argonaute Proteins ; Cell Movement ; physiology ; Cell Proliferation ; physiology ; Exosomes ; physiology ; Fetal Blood ; cytology ; Humans ; Karyotyping ; Mesenchymal Stem Cells ; pathology ; Neoplasm Invasiveness ; Neoplastic Stem Cells ; Umbilical Cord ; Wound Healing

BACKGROUND AND OBJECTIVES: Placenta and blood that remained in the umbilical cord is routinely available as a discarded tissue after deliveries and it is free of any legal, moral, ethical or religious objections, providing a high number of multipotent CD34+ progenitor and stem cells. Using ex vivo isolated CD34+ cells from human umbilical cord blood (hUCB) have emerged as promising candidates to treat various diseases, including exogenous pathogenic infections. We have expanded to build a rational approach to study the effect of CD34+ cells after damaged liver tissues by the devastating human parasitic flatworm Schistosoma mansoni. METHODS AND RESULTS: Experimental studies were conducted in the Department of Zoology, Faculty of Science and Departments of Parasitology and Physiology, Faculty of Medicine, SCU, Egypt. We have studied the impact of ex vivo preparation of CD34+ cells from hUCB on S. mansoni-induced liver fibrosis de novo, and treated for shorter and longer periods in vivo. Ova count, ALT and albumin were measured at specific time interval and histopathological examination of liver was conducted to confirm the biochemical results. The data obtained were statistically analyzed by ANOVA between groups. It was found that the administration of CD34+ cells have modestly reduced liver damage; reduced the S. mansoni infection associated elevation in serum levels of ALT; significantly improved serum levels of albumin and reduced egg granuloma diameter in the livers. CONCLUSIONS: We demonstrated that CD34+ cells can markedly ameliorated liver fibrosis in vivo and may be beneficial for therapy to recover organ structure and/or function of S. mansoni-infected mice.
Animals ; Egypt ; Fetal Blood ; Fibrosis ; Granuloma ; Humans ; Liver ; Liver Cirrhosis ; Mice* ; Ovum ; Parasitology ; Physiology ; Placenta ; Platyhelminths ; Schistosoma mansoni* ; Stem Cells ; Umbilical Cord ; Zoology

OBJECTIVE: Leptin, the protein encoded by the Ob gene in the adipose cell, is produced by the placenta during pregnancy and materanal serum leptin is increased in preeclampsia. The objective of this study was to compare umbilical cord plasma leptin level between infants of mothers who experienced preeclampsia and infants of control subjects and to understand the physiology of leptin. METHODS: Leptin concentrations were measured in cord blood at birth using a specific radioimmunoassay employing human recombinant leptin (Human leptin RIA kit; Linco Research, Inc. U.S.A.). We compared cord plasma leptin between preeclamptic (n=17 women) and normal pregnancies (n=21 women). RESULTS: Gestational age is the only one significant variable among the demographic variables (P=0.011). There was no statistically significant difference in cord plasma leptin level between infants of mothers who experienced preeclampsia and infants of control subjects, but preeclampsia group had slightly lower leptin levels than control subjects (Control subjects: 4.8 [3.7-7.9] ng/ml, Preeclamptic women: 2.7 [2.3-6.8] ng/ml, P=0.142). There was also no difference in the leptin value adjusted for different gestational age, or ratio between cord plasma leptin level and gestational age (Control subjects: 0.017 [0.013-0.018], Preeclamptic women: 0.010 [0.008-0.025], P=0.131). CONCLUSION: We found no difference between umbilical cord plasma leptin in infants of mothers who had preeclampsia and umbilical cord plasma leptin in infants of control subjects, but insignificantly lower levels of umbilical cord plasma leptin in infants of mothers who had preeclampsia. It suggest that maternal serum concentration do not correlate with cord leptin concentration and dysregulation of leptin metabolism and/or function in the placenta may be implicated in the pathogenesis of preeclampsia.
Female ; Fetal Blood ; Gestational Age ; Humans ; Infant ; Leptin* ; Metabolism ; Mothers ; Parturition ; Physiology ; Placenta ; Plasma* ; Pre-Eclampsia ; Pregnancy ; Pregnant Women* ; Radioimmunoassay ; Umbilical Cord*

BACKGROUNDIslet transplantation is an effective way of reversing type I diabetes. However, islet transplantation is hampered by issues such as immune rejection and shortage of donor islets. Mesenchymal stem cells can differentiate into insulin-producing cells. However, the potential of human umbilical cord mesenchymal stem cells (huMSCs) to become insulin-producing cells remains undetermined.

METHODSWe isolated and induced cultured huMSCs under islet cell culture conditions. The response of huMSCs were monitored under an inverted phase contrast microscope. Immunocytochemical and immunofluorescence staining methods were used to measure insulin and glucagon protein levels. Reverse transcription-polymerase chain reaction (RT-PCR) was performed to detect gene expression of human insulin and PDX-1. Dithizone-staining was employed to determine the zinc contents in huMSCs. Insulin secretion was also evaluated through radioimmunoassay.

RESULTSHuMSCs induced by nicotinamide and β-mercaptoethanol or by neurogenic differentiation 1 gene (NeuroD1) transfection gradually changed morphology from typically elongated fibroblast-shaped cells to round cells. They had a tendency to form clusters. Immunocytochemical studies showed positive expression of human insulin and glucagon in these cells in response to induction. RT-PCR experiments found that huMSCs expressed insulin and PDX-1 genes following induction and dithizone stained the cytoplasm of huMSCs a brownish red color after induction. Insulin secretion in induced huMSCs was significantly elevated compared with the control group (t = 6.183, P < 0.05).

CONCLUSIONSHuMSCs are able to differentiate into insulin-producing cells in vitro. The potential use of huMSCs in β cell replacement therapy of diabetes needs to be studied further.

Cell Differentiation ; genetics ; physiology ; Cells, Cultured ; Cellular Reprogramming ; genetics ; physiology ; Female ; Humans ; Immunohistochemistry ; Insulin-Secreting Cells ; cytology ; metabolism ; Mesenchymal Stromal Cells ; cytology ; Pregnancy ; Reverse Transcriptase Polymerase Chain Reaction ; Umbilical Cord ; cytology ; Wharton Jelly ; cytology