Prediction of the temperature distribution of partially submersed umbilical cables

The objective of this work is to predict the temperature distribution of partially submersed umbilical cables under different operating and environmental conditions. The commercial code Fluent® was used to simulate the heat transfer and the air fluid flow of part of a vertical umbilical cable near the air-water interface. A free-convective three-dimensional turbulent flow in open-ended vertical annuli was solved. The influence of parameters such as the heat dissipating rate, wind velocity, air temperature and solar radiation was analyzed. The influence of the presence of a radiation shield consisting of a partially submersed cylindrical steel tube was also considered. The air flow and the buoyancydriven convective heat transfer in the annular region between the steel tube and the umbilical cable were calculated using the standard k-ε turbulence model. The radiative heat transfer between the umbilical external surface and the radiation shield was calculated using the Discrete Ordinates model. The results indicate that the influence of a hot environment and intense solar radiation may affect the umbilical cable performance in its dry portion.

[Complex umbilical cord vein pulsations in cases with twin-twin transfusion syndrome: prognostic implications]

Umbilical vein pulsations (UV-P) are due to various etiologies. The aim of the present study was to investigate the incidence and type of UV-P in monochorionic twins with twin-twin transfusion syndrome (TTTS).

Single umbilical artery in twin pregnancies

Our purpose was to evaluate the antenatal incidence of single umbilical artery (SUA) in twin pregnancies according to chorionicity and to assess its relationship with outcome.

Evaluation of the isoflurane-sparing effects of lidocaine infusion during umbilical surgery in calves

OBJECTIVE: To evaluate the isoflurane-sparing effects of lidocaine administered by constant rate infusion (CRI) during umbilical surgery in calves. STUDY DESIGN: Randomized 'blinded' prospective clinical study. ANIMALS: Thirty calves (mean 4.7 +/- SD 2.5 weeks old) undergoing umbilical surgery. METHODS: After premedication with xylazine (0.1 mg kg(-1) , IM), anaesthesia was induced with ketamine (4 mg kg(-1) , IV) and maintained with isoflurane in O(2) administered through a circle breathing system. The calves were assigned randomly to receive a bolus of 2 mg kg(-1) lidocaine IV after induction of anaesthesia, followed by CRI of 50 mug kg(-1) minute(-1) (group L, n=15) or a bolus and CRI of 0.9% sodium chloride (NaCl, group S, n=15). End-tidal isoflurane was adjusted to achieve adequate depth of anaesthesia. Heart rate, direct arterial blood pressure and body temperature were measured intraoperatively. Groups were compared by t- tests, anova or Mann-Whitney rank sum test as appropriate. RESULTS: The end-tidal concentration of isoflurane (median, IQR) was significantly lower in group L [1.0% (0.94-1.1)] compared to group S [1.2% (1.1-1.5)], indicating a 16.7% reduction in anaesthetic requirement during lidocaine CRI. Cardiopulmonary parameters and recovery times did not differ significantly between groups. CONCLUSION AND CLINICAL RELEVANCE: Lidocaine CRI may be used as a supplement to inhalation anaesthesia during umbilical surgery in calves in countries where such a protocol would be within the legal requirements for veterinary use in food animals. This study did not show any measurable benefit to the calves other than a reduction in isoflurane requirement.

Stem Cells From Umbilical Cord Wharton's Jelly From Preterm Birth Have Neuroglial Differentiation Potential

Objective:The aim of the study is to determine the neuroglial differentiation potential of human Wharton's jelly-derived mesenchymal stem cells (WJ-MSCs) from preterm birth when compared to term delivery.Study Design:The WJ-MSCs from umbilical cords of preterm birth and term controls were isolated and induced into neural progenitors. The cells were analyzed for neuroglial markers by flow cytometry, real-time polymerase chain reaction, and immunocytochemistry. Results:Independent of gestational age, a subset of WJ-MSC displayed the neural progenitor cell markers Nestin and Musashi-1 and the mature neural markers microtubule-associated protein 2, glial fibrillary acidic protein, and myelin basic protein. Neuroglial induction of WJ-MSCs from term and preterm birth resulted in the enhanced transcription of Nestin and Musashi-1.Conclusions:Undifferentiated WJ-MSCs from preterm birth express neuroglial markers and can be successfully induced into neural progenitors similar to term controls. Their potential use as cellular graft in neuroregenerative therapy for peripartum brain injury in preterm birth has to be tested.

Use of human embryonic stem cells and umbilical cord blood stem cells for research and therapy: a prospective survey among health care professionals and patients in Switzerland

BACKGROUND: Scientific progress in the biology of hematopoietic stem cells (HSCs) provides opportunities for advances in therapy for different diseases. While stem cell sources such as umbilical cord blood (UCB) are unproblematic, other sources such as human embryonic stem cells (hESCs) raise ethical concerns. STUDY DESIGN AND METHODS: In a prospective survey we established the ethical acceptability of collection, research, and therapy with UCB HSCs versus hESCs among health care professionals, pregnant women, patients undergoing in vitro fertilization therapy, parents, and HSC donors and recipients in Switzerland. RESULTS: There was overall agreement about an ethical justification for the collection of UCB for research and therapy in the majority of participants (82%). In contrast, research and therapy with hESCs was acceptable only by a minority (38% of all responders). The collection of hESCs solely created for HSC collection purposes met overall with the lowest approval rates. Hematologists displayed among the participants the highest acceptance rates for the use of hESCs with 55% for collection, 63% for research, and 73% for therapy. CONCLUSIONS: This is the first study assessing the perception of hESCs for research and therapy in comparison with UCB HSCs in different target groups that are exposed directly, indirectly, or not at all to stem cell-based medicine. Our study shows that the debate over the legitimacy of embryo-destructive transplantation medicine is far from over as particularly hESC research continues to present an ethical problem to an overwhelming majority among laypersons and even among health care professionals.

High acceptance rate of hybrid allogeneic-autologous umbilical cord blood banking among actual and potential Swiss donors

Two competitive concepts of umbilical cord blood (UCB) banking are currently available: either allogeneic UCB is donated to a public bank or autologous cells are stored in a private bank. Allogeneic-autologous hybrid banking is a new concept that combines these two approaches. However, acceptance of hybrid UCB banking among potential donors is unknown to date.

Sonographic Assessment of the Umbilical Cord

The umbilical cord is not an inert structure, suspended between the fetus and placenta, but it plays an active role and it is involved in several processes afflicting the feto-placental unit. Its study has to be regarding not only its morphology and morphometry, and the impendance of blood flow by Doppler waveform analysis, but it includes also an analysis of the coiling type and the amount of the Wharton Jelly. The umbilical cord has been considered like an important and huge source of informations, useful to assess the well-being of the fetus and the outcome of pregnancy. The standardization of ultrasound techniques is the first step to speak the same language and make the study of this structure a fundamental part of well-being fetus assessment. This article is carefully focused on morphologic, morphometric and functional ultrasound examination of umbilical cord and suggests that any anomaly detected should provide an indication for an intense fetal follow-up, useful for early helpful therapy, preventing serious complication for the pregnancy.

Small omphalocele with umbilical evagination. A distinct entity?

A neonatal case of umbilical evagination of the bladder combined with a small omphalocele is presented. This rare congenital malformation has previously been described in only three cases. Umbilical evagination can be understood as a disturbance of development of both the vitelline and allantoic ducts, resulting in a non-descended but otherwise normal bladder opening to the inferior margin of a small omphalocele. Diagnosis is made by clinical inspection and ultrasound. Since other malformations are not present, this entity may be regarded as a minor form of a lower midline defect with excellent prognosis.