Reactivity of isolated human chorionic vessels: analysis of some influencing variables

2003 ◽  
Vol 81 (12) ◽  
pp. 1147-1151 ◽  
Author(s):  
Antonio Abad ◽  
Luis Estañ ◽  
Francisco J Morales-Olivas ◽  
Vicente Serra

The aim of the study was to determine whether 24 h of cold storage of samples, mode of delivery, and gestational age influenced in vitro human chorionic vascular reactivity (35 arteries and 34 veins). The following groups were compared: (i) fresh versus 24-h cold-stored (4 °C in Krebs–Henseleit solution) chorionic vascular rings from normal term placentas, (ii) fresh chorionic vascular rings from normal term placentas obtained after vaginal delivery versus those obtained after elective caesarean section, and (iii) fresh chorionic vascular rings from normal term placentas versus those obtained from preterm deliveries. Isometric recording of the concentration–response curve to KCl (5–120 mM) was assesed in each group. In vitro human chorionic vascular reactivity was influenced negatively by the 24-h cold storage of samples, with only 30% of stored samples being weakly reactive to KCl. Human chorionic vascular reactivity to KCl was unaffected by the mode of delivery. However, the response to KCl was gestational-age dependent. Thus, preterm vascular rings exhibited a significantly (P < 0.05) decreased response (Emax = 9.8 ± 0.0 mN; EC50 = 26.0 ± 1.3 mM) compared with term samples (Emax = 21.6 ± 2 mN; EC50 = 13.9 ± 1.6 mM). In conclusion, this study provides evidence that fresh term vascular rings are the tissues of choice for studying human chorionic vascular reactivity.Key words: human chorionic vessels, placenta, vascular reactivity.

1979 ◽  
Vol 57 (8) ◽  
pp. 825-831 ◽  
Author(s):  
F. Coceani ◽  
E. White ◽  
E. Bodach ◽  
P. M. Olley

Circular strips of ductus arteriosus from lambs of gestational age between 90 and 144 days (term 147 days) were studied in vitro at low (8–16 torr (1 torr = 133.322 Pa)) and high (426–622 torr) [Formula: see text]. Potassium- and oxygen-induced contractions increased with the gestational age and attained a maximum at term. At low [Formula: see text], ibuprofen, a blocker of prostaglandin synthesis, produced a dose-dependent contraction of the ductus at all ages and enhanced the potassium-induced contraction of the immature ductus (90–124 days). Both effects were relatively greater in the 103- to 107-day gestational group. At that age, ibuprofen also potentiated the oxygen-induced contraction. These findings, while confirming that a prostaglandin is involved in ductus patency, indicate that the prostaglandin-relaxing mechanism becomes functional at an early stage of gestation and reaches maximal activity before term. The existence of an active, prostaglandin-mediated relaxation in the preterm ductus may account, in part, for the reduced responsiveness of the vessel to oxygen. It is confirmed that ibuprofen and other nonsteroidal antiinflammatory drugs are well suited for the management of the premature infant with patent ductus arteriosus.


Author(s):  
Henry H. Eichelberger ◽  
John G. Baust ◽  
Robert G. Van Buskirk

For research in cell differentiation and in vitro toxicology it is essential to provide a natural state of cell structure as a benchmark for interpreting results. Hypothermosol (Cryomedical Sciences, Rockville, MD) has proven useful in insuring the viability of synthetic human epidermis during cold-storage and in maintaining the epidermis’ ability to continue to differentiate following warming.Human epidermal equivalent, EpiDerm (MatTek Corporation, Ashland, MA) consisting of fully differentiated stratified human epidermal cells were grown on a microporous membrane. EpiDerm samples were fixed before and after cold-storage (4°C) for 5 days in Hypothermosol or skin culture media (MatTek Corporation) and allowed to recover for 7 days at 37°C. EpiDerm samples were fixed 1 hour in 2.5% glutaraldehyde in sodium cacodylate buffer (pH 7.2). A secondary fixation with 0.2% ruthenium tetroxide (Polysciences, Inc., Warrington, PA) in sodium cacodylate was carried out for 3 hours at 4°C. Other samples were similarly fixed, but with 1% Osmium tetroxide in place of ruthenium tetroxide. Samples were dehydrated through a graded acetone series, infiltrated with Spurrs resin (Polysciences Inc.) and polymerized at 70°C.


Hypertension ◽  
1996 ◽  
Vol 28 (3) ◽  
pp. 361-366 ◽  
Author(s):  
Daniel Henrion ◽  
Fiona J. Dowell ◽  
Bernard I. Levy ◽  
Jean-Baptiste Michel

2019 ◽  
Vol 12 (12) ◽  
pp. e232967 ◽  
Author(s):  
Cathy Rowland ◽  
Daniel Kane ◽  
Maeve Eogan

A 34-year-old primiparous woman presented in spontaneous labour and had an unassisted vaginal birth of a 3.5 kg infant. Postnatally, the patient experienced lower limb weakness and was unable to mobilise unassisted. A diagnosis of postpartum femoral neuropathy was made. Full recovery of normal motor function was not achieved until 5 months postpartum. She returned in her next pregnancy, seeking advice on how to avoid this complication from reoccurring. It was decided that an elective caesarean section was an appropriate mode of delivery, which she underwent at 39 weeks without complication and without recurrence of the femoral neuropathy.


2021 ◽  
pp. 004947552199134
Author(s):  
Avinash Lomash ◽  
Abhinaya Venkatakrishnan ◽  
Meenakshi Bothra ◽  
Bhavna Dhingra ◽  
Praveen Kumar ◽  
...  

Atypical coeliac disease in young children is frequently missed when it presents atypically as non-gastrointestinal presentations to different specialties. There was a greater delay (54 months) in establishing the diagnosis in those with atypical coeliac disease (p < 0.001). No difference was observed in the mode of delivery or duration of breast feeding, but significant difference was observed between gestational age at birth (p < 0.001). Most cases showed stunted growth and underweight. Irritability, anaemia, rickets, dermatitis herpetiformis, alopecia and intussusception were other common predictors of atypical coeliac disease. Because of a myriad spectrum of non-gastrointestinal symptoms, at any age with diverse presentation, a high index of suspicion is therefore required.


2020 ◽  
Vol 7 ◽  
pp. 2333794X2098130
Author(s):  
Ebissa Bayana Kebede ◽  
Adugna Olani Akuma ◽  
Yonas Biratu Tarfa

Background: Perinatal asphyxia is a severe problem which causes serious problem in neonates in developing countries. This study is aimed to determine magnitude of perinatal asphyxia and its associated factors. Methods: A cross-sectional study design was conducted among neonates admitted over a period of 4 years on 740 samples. Systematic sampling method was employed to get required samples from log book. Epi-data 3.1 is used for data entry and the entered data was exported to SPSS Version 23 for analysis. Bivariable and multiple variable logistic regressions analysis were applied to see the association between dependent and independent variables. Finally, P-value <.05 at 95% CI was declared statistically significant. Results: The main significant factor associated to perinatal asphyxia were prolonged labor ( P = .04, AOR = 1.68 95%CI: [1.00, 2.80]), being primipara ( P = .003, AOR = 2.06, 95%CI: [1.28, 3.30]), Small for Gestational Age (SGA) ( P = .001, AOR = 4.35, 95%CI: [1.85, 10.19]), Large for Gestational Age ( P = .001, AOR = 16.75, 95%CI: [3.82, 73.33]) and mode of delivery. Conclusion: The magnitude of perinatal asphyxia was 18%. Prolonged labor, parity, birth size, mode of delivery, and APGAR score at 1st minute were significantly associated with perinatal asphyxia. So, Nurses, Midwives, Medical Doctors, and health extension workers have to engage and contribute to on how to decrease the magnitude of perinatal asphyxia.


2021 ◽  
Vol 11 (3) ◽  
pp. 1178
Author(s):  
Evanthia Tsoukou ◽  
Maxime Delit ◽  
Louise Treint ◽  
Paula Bourke ◽  
Daniela Boehm

The spread of multidrug-resistant bacteria poses a significant threat to human health. Plasma activated liquids (PAL) could be a promising alternative for microbial decontamination, where different PAL can possess diverse antimicrobial efficacies and cytotoxic profiles, depending on the range and concentration of their reactive chemical species. In this research, the biological activity of plasma activated water (PAW) on different biological targets including both microbiological and mammalian cells was investigated in vitro. The aim was to further an understanding of the specific role of distinct plasma reactive species, which is required to tailor plasma activated liquids for use in applications where high antimicrobial activity is required without adversely affecting the biology of eukaryotic cells. PAW was generated by glow and spark discharges, which provide selective generation of hydrogen peroxide, nitrite and nitrate in the liquid. The PAW made by either spark or glow discharges showed similar antimicrobial efficacy and stability of activity, despite the very different reactive oxygen species (ROS) and reactive nitrogen species profiles (RNS). However, different trends were observed for cytotoxic activities and effects on enzyme function, which were translated through the selective chemical species generation. These findings indicate very distinct mechanisms of action which may be exploited when tailoring plasma activated liquids to various applications. A remarkable stability to heat and pressure was noted for PAW generated with this set up, which broadens the application potential. These features also suggest that post plasma modifications and post generation stability can be harnessed as a further means of modulating the chemistry, activity and mode of delivery of plasma functionalised liquids. Overall, these results further understanding on how PAL generation may be tuned to provide candidate disinfectant agents for biomedical application or for bio-decontamination in diverse areas.


2018 ◽  
Vol 30 (1) ◽  
pp. 67-78 ◽  
Author(s):  
Ramadan A. Hassanein ◽  
Ehab A. Salem ◽  
Ahmed A. Zahran

AbstractThis study was performed to explore the efficacy of combining more than one postharvest treatment in maintaining some quality attributes and reducing fungal pathogenicity in cold-stored guava fruits. The investigated postharvest treatments included the control, CaCl2(4%), lemongrass oil (2 dm3kg−1), gamma (γ) irradiation (0.2, 0.4 and 0.6 kGy), 0.4 kGy γ irradiation + CaCl2(4%), and 0.4 kGy γ irradiation + lemongrass oil (2 dm3kg−1). The studied physiochemical attributes included weight loss, decay percentage, fruit firmness, total soluble solids (TSS), titratable acidity (TA), and vitamin C content. Different fungal species were also isolated from decayed fruits and were identified asAlternaria alternata,Alternaria solani,Aspergillus niger,Botrytis cinerea,Fusarium solaniandRhizopus stolonifer. The severity of infection for the different fungi was determined, and anin vitroantifungal assay was conducted for lemongrass oil. All the investigated treatments generally reduced decay and water loss percentages, and controlled TSS, TA and vitamin C decrements that occurred during cold storage. On the other hand, higher irradiation doses generally increased fruit softness, and the 0.4 kGy γ dose did not contribute to the overall fruit quality when coupled with CaCl2and lemongrass oil, compared to CaCl2and lemongrass oil treatments alone.


1991 ◽  
Vol 11 (1) ◽  
pp. 161-164 ◽  
Author(s):  
Mária Faragó ◽  
Csaba Szabó ◽  
Eörs Dóra ◽  
Ildikó Horváth ◽  
Arisztid G. B. Kovách

To clarify the effect of extracellular magnesium (Mg2+) on the vascular reactivity of feline isolated middle cerebral arteries, the effects of slight alterations in the Mg2+ concentration on the contractile and endothelium-dependent dilatory responses were investigated in vitro. The contractions, induced by 10−8-10−5 M norepinephrine, were significantly potentiated at low Mg2+ (0.8 m M v. the normal, 1.2 m M). High (1.6 and 2.0 m M) Mg2+ exhibited an inhibitory effect on the contractile responses. No significant changes, however, in the EC50 values for norepinephrine were found. The endothelium-dependent relaxations induced by 108–10−5 M acetylcholine were inhibited by high (1.6 and 2.0 m M) Mg2+. Lowering of the Mg2+ concentration to 0.8 m M or total withdrawal of this ion from the medium failed to alter the dilatory potency of acetylcholine. The changes in the dilatory responses also shifted the EC50 values for acetylcholine to the right. The present results show that the contractile responses of the cerebral arteries are extremely susceptible to the changes of Mg2+ concentrations. In response to contractile and endothelium-dependent dilatory agonists, Mg2+ probably affects both the calcium influx into the endothelial and smooth muscle cells as well as the binding of acetylcholine to its endothelial receptor. Since Mg2+ deficiency might facilitate the contractile but not the endothelium-dependent relaxant responses, the present study supports a role for Mg2+ deficiency in the development of the cerebral vasospasm.


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