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Clinical Trial 2013; 34(7): 687-692 PubMed PMID: 24463995 Citation  Keywords:  Adult, Dose-Response Relationship, Drug, Female, Fetus:blood supply, Hemodynamics:drug effects, Humans, Middle Cerebral Artery:drug effects, Nifedipine:administration & dosage, Obstetric Labor, Premature:diagnostic imaging, Placenta:blood supply, Pregnanc.   

OBJECTIVES: The aims were to assess the placental and fetal circulation during nifedipine tocolysis within the first 48 hours of therapy.

METHODS: Placental and fetal circulation was assessed in Doppler ultrasound examination prior to nifedipine administration and then after 24 and 48 hours. Maternal heart rate and PI in uterine arteries were evaluated as well as FHR, RI and PI of UA and MCA. E/A-wave ratio for A-V valves, MPI and SF were calculated for both ventricles independently. To determine changes over time in all study variable analysis of variance (ANOVA) for repeated measurements followed by Tukey-Kramer's multiple comparison test was used. The effects of additional clinical covariates were checked.

RESULTS: Uterine and umbilical blood flow patterns were not altered significantly during administration of nifedypine tocolysis. While MCA Doppler indicies such as RI and PI were unchanged, the evaluation of MCA PSV revealed a transient significant decrease after 24 hours. A resolution of this distraction was observed within the following 24 hours. No significant changes were observed in direct fetal cardiac function parameters calculated separately for both ventricles.

CONCLUSIONS: The decrease of MCA PSV after 24 hours of treatment was isolated and transient hemodynamic distraction observed during treatment. Neither fetal cardiac parameters nor other Doppler indices were changed. Therefore oral administration of nifedipine seems not to alter uterine nor fetal arterial blood flow pattern seriously. As significant changes were observed by different authors, further studies should be performed to verify the optimal total dose of nifedipine and its influence on hemodynamic conditions....

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Journal Article 2008; 29(4): 493-499 PubMed PMID: 18766139 Citation  Keywords:  Adult, Blood Flow Velocity, Deoxyribonucleases, Type II Site-Specific:genetics, Female, Fetal Growth Retardation:genetics, Fetus:anatomy & histology, Genotype, Gestational Age, Humans, Laser-Doppler Flowmetry, Middle Cerebral Artery, Polymorphism, Genetic.   

OBJECTIVES: The intrauterine growth restriction (IUGR) frequently is a cause of fetal morbidity and mortality, and influences perinatal outcome. Several genes have been identified to explain aetiology of IUGR, beside others the gene coding for tumour necrosis factor alpha (TNF-alpha).

DESIGN: To investigate frequency of AlwI polymorphism of TNF-alpha gene and its correlation with TNF-alpha level in maternal serum, Doppler velocimetry and perinatal outcome in pregnancies suspected for IUGR.

SETTING: 42 pregnancies with IUGR and 50 matched healthy pregnant women were included in the study. Maternal venous blood samples were investigated in relationship to blood flow Doppler velocimetry in umbilical (UA) and middle cerebral (MCA) arteries. AlwI polymorphism was analysed using PCR/RFLP assays. TNF-alpha level was evaluated by immunoelectophoretic method.

RESULTS: A higher frequency of mutated -238A alleles (13.1% vs. 7.0%) and genotypes containing at least one mutated -238A allele (23.8% vs. 14.0%) were found in the IUGR group. The tendency to the higher TNF-alpha level in IUGR subgroups with the presence of at least one mutated A allele (258.9+/-231.3 vs. 174.1+/-145.6 pg/ml) was detected. No statistical differences were detected for PI values in UA and MCA arteries considering particular genotypes (GG vs. GA + AA) separately in IUGR group.

CONCLUSION: Increased UA vascular impedance and signs of brain sparing in MCA are related to IUGR and increased TNF-alpha level in maternal serum. AlwI polymorphism might play a role in IUGR aetiology and influence TNF-alpha expression in maternal serum, but was not related to Doppler velocimetry or with perinatal outcome....

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Comparative Study 2007; 28(2): 170-174 PubMed PMID: 17435667 Citation  Keywords:  Animals, Brain Ischemia:drug therapy, Drug Evaluation, Preclinical, Erythropoietin:administration & dosage, Infarction, Middle Cerebral Artery:drug therapy, Injections, Intraperitoneal, Male, Neuroprotective Agents:administration & dosage, Rats, Rats, Spr.   

OBJECTIVE: Majority of severe disabilities in adults are caused by stroke. The aim of our study is to learn the effects of erythropoietin (EPO), on infarct size in cerebral ischemia and to determine neurological behavioral scores and histopathological evaluation.

MATERIAL & METHODS: In this study 30 adult Sprague-Dawney rats were used. Cerebral ischemia was constituted by intraluminal filament method with a 4-0-nylon suture. Reperfusion was started after two hours of middle cerebral artery occlusion. The rats were randomly divided into two groups as follow: control and EPO groups. Saline 0.9% (0.5 ml/kg) and EPO (5 000 U/kg) was administered intraperitoneally in the groups. Three coronal slices in two millimeters thickness were obtained from cerebrum, cerebellum and brain stem, and were stained with a 2% solution of triphenyltetrazolium chloride. Transparent sheets were placed over each section and the areas of the brain and infarct were measured. The neurological scores were determined at 24th, 48th and 72nd hours after reperfusion.

RESULTS: Percent of ischemic area (%) in cerebrum, cerebellum and brain stem level in EPO groups were less than those of control group (p<0.0001). In addition, we determined that EPO group was better than controls of neurologic score and histopathologically after cerebral ischemia.

CONCLUSIONS: We concluded that EPO may decrease ischemic area in experimental cerebral ischemia in rats and it seems that EPO may be beneficial....

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Comparative Study 2002; 23(3): 249-254 PubMed PMID: 12080287 Citation  Keywords:  Animals, Body Temperature, Brain Ischemia:pathology, Infarction, Middle Cerebral Artery:drug therapy, Male, Neuropeptides:pharmacology, Neuroprotective Agents:pharmacology, Pituitary Adenylate Cyclase-Activating Polypeptide, Rats, Rats, Wistar, Vasoactive.   

OBJECTIVES: Pituitary adenylate cyclase activating polypeptide (PACAP) and vasoactive intestinal polypeptide (VIP) belong to the same peptide family, and both neuropeptides have been shown to exert in vitro and in vivo neurotrophic and neuroprotective effects. The aim of the present study was to investigate and compare the protective effects of PACAP and VIP in permanent focal cerebral ischemia in rats. The effect on the progression of the cerebral infarct was also studied.

METHOD: Male rats were injected 450 pmol PACAP or VIP dissolved in physiological saline intracerebroventricularly, preceding the occlusion of the middle cerebral artery. Control animals received vehicle treatment. Permanent focal ischemia was induced by the intraluminal filament occlusion of the middle cerebral artery. Animals were sacrificed 12 or 24 hours after the onset of ischemia, and infarcted brain areas were determined by staining bran sections with triphenyl-tetrazolium chloride.

RESULTS: Twelve hours after ischemia, the infarcted brain volume resulted to be 14.8% in the control group, 15.3% in the VIP-treated group and 5.8% in the PACAP-treated animals. Twenty-four hours after middle cerebral artery occlusion, the infarcted brain volumes were 21.5%, 20.7% and 14.3% in the control, VIP and PACAP-treated animals, respectively.

CONCLUSION: Our results provide further evidence for the neuroprotective effects of PACAP38 as given in form of a preischemic bolus. It slows down the progression of the evolution of the infarct and reduces the final infarct size. In contrast, a related peptide, VIP, does not have neuroprotective effects under the same experimental conditions....

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