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Diffusion-time- ( td) dependent diffusion MRI (dMRI) extends our ability to characterize brain microstructure by measuring dMRI signals at varying td. The use of oscillating gradient (OG) is essential for accessing short td but is technically challenging on clinical MRI systems. This study aims to investigate the clinical feasibility and value of td-dependent dMRI in neonatal hypoxic-ischemic encephalopathy (HIE). Eighteen HIE neonates and six normal term-born neonates were scanned on a 3 T scanner, with OG-dMRI at an oscillating frequency of 33 Hz (equivalent td ≈ 7.5 ms) and pulsed gradient (PG)-dMRI at a td of 82.8 ms and b-value of 700 s/mm2. The td-dependence, as quantified by the difference in apparent diffusivity coefficients between OG- and PG-dMRI (ΔADC), was observed in the normal neonatal brains, and the ΔADC was higher in the subcortical white matter than the deep grey matter. In HIE neonates with severe and moderate injury, ΔADC significantly increased in the basal ganglia (BG) compared to the controls (23.7% and 10.6%, respectively). In contrast, the conventional PG-ADC showed a 12.6% reduction only in the severe HIE group. White matter edema regions also demonstrated increased ΔADC, where PG-ADC did not show apparent changes. Our result demonstrated that td-dependent dMRI provided high sensitivity in detecting moderate-to-severe HIE.

Introduction: Among the hypertensive pathologies of pregnancy, preeclampsia remains the entity responsible for pregnancy complications. Objective: The aim of this work was to determine the frequency of hypertensive pathologies in the peripartum, to determine the maternal and neonatal morbidity factors associated with preeclampsia on the one hand, and on the other hand, to other forms of hypertension in the peripartal period. Patients and methods: This is a cross-sectional study of hypertensive pathologies in per partum over a period of 15 months which have been included any pregnant, parturient and hypertensive childbirth. The data was analyzed using SPSS software version 21.0. Data positioning and dispersion parameters were studied. The factor analysis was performed by determining the odds ratio with a 95% confidence interval and a significance level set at p ≤ 0.05. Results: 142 cases of hypertension were collected from a total of 2988 deliveries, i.e. a frequency of hypertension of 4.8%. The main form of high blood pressure (HBP) was the isolated HBP at 51.4%. 60.3% of primiparas were preeclamptic [OR 2.47 (CI 1.25 - 4.91)], 63.2% of preeclampsia did not follow prenatal consultations [OR 2.43 (CI 1.06 - 5.62)], 63.6% of preeclampsia had moderate and severe threat premature delivery [OR 4.57 (CI 2.11 - 9.99)], neonatal hypoxia in the fifth minute was found in 34.4% of newborns of preeclamptic mothers [OR 3.02 (CI 1.44 - 6.34)], hypotrophy was observed in 41.4% of the cases in the preeclamptic patients [OR 5.41 (IC 1, from 55 to 19.57)]. Conclusion: Preeclampsia is significantly associated with maternal and neonatal morbidity.

Background: Creatine kinase MB (CK-MB), which exists mainly in the cytoplasm of myocardial cells, is currently accepted as an indicator and has high sensitivity and specificity for the diagnosis of myocardial injury. Objective: This study was aimed to estimate serum creatine kinase MB (CK-MB) levels after asphyxia-induced myocardial injury in neonates. Patients and methods: 40 neonates were included in this study and divided into 20 cases with the diagnosis of perinatal hypoxia ischemia and 20 controls admitted to Neonatology Unit of Pediatric Department at Zagazig University. Serum CK-MB levels were estimated in all studied neonates. Results: In the present study serum CK-MB levels in cases were significantly higher than controls. A significant area under curve with cutoff >14.5 (units /L) with sensitivity 99%and specificity 97.5% for CK-MB. Encephalopathy cases were significantly associated with higher HR and CKMB. Cases with organ failure were significantly associated with higher HR and CKMB. Cases with metabolic acidosis were significantly associated with higher HR and CKMB. Conclusion: It could be concluded that cases with hypoxic ischemic encephalopathy (HIE) and those with multiple organ failure had a more pronounced elevation of serum CK-MB compared with cases of hypoxia-ischemia with no organ failure. Similarly, patients with HIE had significant elevation of cardiac enzymes. Collectively, these findings indicate more myocardial systolic dysfunction and damage in neonates with HIE and organ failure.

Neonatal hypoxia-ischemia (HI) is responsible for movement disorders in preterm infants. Non-pharmacological strategies, such as environmental enrichment (EE) during adulthood, have shown positive effects on promoting sensorimotor recovery after HI. However, little is known about the effects of perinatal EE on sensorimotor function following HI. In present study we investigated the hypothesis that enriched experiences during pregnancy and lactation would reduce motor impairments caused by a model of neonatal HI in rats. At postnatal day (PND) 3, Wistar pups of both sexes were subject to the modified Rice-Vannucci model. Motor function was evaluated from PND 60 to PND 64. HI caused a reduction in the forepaws strength and worsening of movement quality in the right forepaw. These effects were attenuated in animals receiving prenatal or lactational EE, which showed better performance when compared to the control group. Moreover, enriched experiences during lactation reversed HI-induced asymmetric use of the forepaws and the trend to increased paw errors in a walking test. Lower scores were found in the contralateral forepaw placement in HI animals, except when EE was provided at both stages of neurodevelopment . These results indicate that enriched experiences reduce motor impairments, i.e , measured in force, asymmetry and coordination domains, and that EE during lactation is more effective in promoting post-injury recovery. These data support that early therapeutic interventions might enhance functional reorganization at a period of high brain plasticity and that enriched-like experience might be encouraged in pediatric rehabilitation programs, in order to reduce long-term movement disorders after neonatal brain insults.

Vaisiaus kraujagyslių pirmeiga (VKP) yra labai reta patologija, kurios nediagnozavus laiku, dėl didelės naujagimių hipoksijos ir nukraujavimo rizikos smarkiai sumažėja naujagimių išgyvenamumas. Prenatalinė VKP diagnozė ir tinkamai pasirinktas cezario pjūvio operacijos laikas yra būdas išvengti nepalankios nėštumo baigties. Šiuo metu nėra pakankamai aukšto lygio mokslinių įrodymų dėl virkštelės tvirtinimosi vietos nustatymo įtraukimo į standartinį ultragarsinio tyrimo protokolą. Straipsnyje pristatomas prenataliai nediagnozuotos VKP atvejis ir pateikiama literatūros apžvalga.

The connection between early brain injury and subsequent development of disorders is unknown. Neonatal hypoxia-ischemia (HI) alters circuits associated with subplate neurons (SPNs). SPNs are among the first maturing cortical neurons, project to thalamorecipient layer 4 (L4), and are required for the development of thalamocortical connections. Thus, early HI might influence L4 and such influence might persist. We investigated functional circuits to L4 neurons in neonatal rat HI models of different severities (mild and moderate) shortly after injury and at adolescence. We used laser-scanning photostimulation in slices of auditory cortex during P5–10 and P18–23. Mild injuries did not initially (P6/P7) alter the convergence of excitatory inputs from L2/3, but hyperconnectivity emerged by P8–10. Inputs from L4 showed initial hypoconnectivity which resolved by P8–10. Moderate injuries resulted in initial hypoconnectivity from both layers which resolved by P8–10 and led to persistent strengthening of connections. Inhibitory inputs to L4 cells showed similar changes. Functional changes were mirrored by reduced dendritic complexity. We also observed a persistent increase in similarity of L4 circuits, suggesting that HI interferes with developmental circuit refinement and diversification. Altogether, our results show that neonatal HI injuries lead to persistent changes in intracortical connections.

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Perinatal Asphyxia (PA) is a leading cause of motor and neuropsychiatric disability associated with sustained oxidative stress, neuroinflammation, and cell death, affecting brain development. Based on a rat model of global PA, we investigated the neuroprotective effect of intranasally administered secretome, derived from human adipose mesenchymal stem cells (MSC-S), preconditioned with either deferoxamine (an hypoxia-mimetic) or TNF-&alpha, +IFN-&gamma, (pro-inflammatory cytokines). PA was generated by immersing fetus-containing uterine horns in a water bath at 37 &deg, C for 21 min. Thereafter, 16 &mu, L of MSC-S (containing 6 &mu, g of protein derived from 2 &times, 105 preconditioned-MSC), or vehicle, were intranasally administered 2 h after birth to asphyxia-exposed and control rats, evaluated at postnatal day (P) 7. Alternatively, pups received a dose of either preconditioned MSC-S or vehicle, both at 2 h and P7, and were evaluated at P14, P30, and P60. The preconditioned MSC-S treatment (i) reversed asphyxia-induced oxidative stress in the hippocampus (oxidized/reduced glutathione), (ii) increased antioxidative Nuclear Erythroid 2-Related Factor 2 (NRF2) translocation, (iii) increased NQO1 antioxidant protein, (iv) reduced neuroinflammation (decreasing nuclearNF-&kappa, B/p65 levels and microglial reactivity), (v) decreased cleaved-caspase-3 cell-death, (vi) improved righting reflex, negative geotaxis, cliff aversion, locomotor activity, anxiety, motor coordination, and recognition memory. Overall, the study demonstrates that intranasal administration of preconditioned MSC-S is a novel therapeutic strategy that prevents the long-term effects of perinatal asphyxia.

The recently developed oscillating-gradient diffusion MRI (OG-dMRI) technique extends our ability to examine brain structures at different spatial scales. In this study, we investigated the sensitivity of OG-dMRI in detecting cellular and subcellular structural changes in a mouse model of neonatal hypoxia ischemia (HI). Neonatal mice received unilateral HI injury or sham injury at postnatal day 10, followed by in vivo T2-weighted and diffusion MRI of the brains at 3–6 h and 24 h after HI. Apparent diffusion coefficient (ADC) maps were acquired using conventional pulsed-gradient dMRI (PG-dMRI) and OG-dMRI with oscillating frequencies from 50 to 200 Hz. Pathology at cellular and subcellular levels was evaluated using neuronal, glial, and mitochondrial markers. We found significantly higher rates of ADC increase with oscillating frequencies (Δ fADC) in the ipsilateral edema region, compared to the contralateral side, starting as early as 3 h after HI. Even in injured regions that showed no apparent change in PG-ADC or pseudo-normalized PG-ADC measurements, Δ fADC remained significantly elevated. Histopathology showed swelling of sub-cellular structures in these regions with no apparent whole-cell level change. These results suggest that OG-dMRI is sensitive to subcellular structural changes in the brain after HI and is less susceptible to pseudo-normalization than PG-dMRI.

Perinatal asphyxia (PA) is a relevant cause of death at the time of labour, and when survival is stabilised, associated with short- and long-term developmental disabilities, requiring inordinate care by health systems and families. Its prevalence is high (1 to 10/1000 live births) worldwide. At present, there are few therapeutic options, apart from hypothermia, that regrettably provides only limited protection if applied shortly after the insult. PA implies a primary and a secondary insult. The primary insult relates to the lack of oxygen, and the secondary one to the oxidative stress triggered by re-oxygenation, formation of reactive oxygen (ROS) and reactive nitrogen (RNS) species, and overactivation of glutamate receptors and mitochondrial deficiencies. PA induces overactivation of a number of sentinel proteins, including hypoxia-induced factor-1α (HIF-1α) and the genome-protecting poly(ADP-ribose) polymerase-1 (PARP-1). Upon activation, PARP-1 consumes high amounts of ATP at a time when this metabolite is scarce, worsening in turn the energy crisis elicited by asphyxia. The energy crisis also impairs ATP-dependent transport, including glutamate re-uptake by astroglia. Nicotinamide, a PARP-1 inhibitor, protects against the metabolic cascade elicited by the primary stage, avoiding NAD+ exhaustion and the energetic crisis. Upon re-oxygenation, however, oxidative stress leads to nuclear translocation of the NF-κB subunit p65, overexpression of the pro-inflammatory cytokines IL-1β and TNF-α, and glutamate-excitotoxicity, due to impairment of glial-glutamate transport, extracellular glutamate overflow, and overactivation of NMDA receptors, mainly of the extrasynaptic type. This leads to calcium influx, mitochondrial impairment, and inactivation of antioxidant enzymes, increasing further the activity of pro-oxidant enzymes, thereby making the surviving neonate vulnerable to recurrent metabolic insults whenever oxidative stress is involved. Here, we discuss evidence showing that (i) inhibition of PARP-1 overactivation by nicotinamide and (ii) inhibition of extrasynaptic NMDA receptor overactivation by memantine can prevent the short- and long-term consequences of PA. These hypotheses have been evaluated in a rat preclinical model of PA, aiming to identify the metabolic cascades responsible for the long-term consequences induced by the insult, also assessing postnatal vulnerability to recurrent oxidative insults. Thus, we present and discuss evidence demonstrating that PA induces long-term changes in metabolic pathways related to energy and oxidative stress, priming vulnerability of cells with both the neuronal and the glial phenotype. The effects induced by PA are region dependent, the substantia nigra being particularly prone to cell death. The issue of short- and long-term consequences of PA provides a framework for addressing a fundamental issue referred to plasticity of the CNS, since the perinatal insult triggers a domino-like sequence of events making the developing individual vulnerable to recurrent adverse conditions, decreasing his/her coping repertoire because of a relevant insult occurring at birth.

Although the adverse effects of neonatal hypoxia associated with premature birth on the central nervous system are well known, the contribution of hypoxic damage to the peripheral nervous system (PNS) has not been addressed. We demonstrate that neonatal hypoxia results in hypomyelination and delayed axonal sorting in mice leading to electrophysiological and motor deficits that persist into adulthood. These findings support a potential role for PNS hypoxic damage in the motor impairment that results from premature birth and suggest that therapies designed to protect the PNS may provide clinical benefit.

Introduction: Perinatal asphyxia is one of the most common primary causes of mortality and morbidity among neonates. Perinatal asphyxia will result in neonatal hypoxia and tissue/organ injury. Objective: The aim of this study was to observe the Co-relation between Perinatal asphyxia with Hypoxic Ischemic Encephalopathy (PNA with HIE) and Blood sugar level. Methodology: This is a descriptive cross-sectional case study where a total of 182 neonates were admitted to the hospital with the problem of Perinatal asphyxia with Hypoxic Ischemic Encephalopathy and with some other associated problem. Result: Among the cases, 114 (62.6%) were Boys and 68 (37.45%) Girls. The mean age was 29.72 ± 78.42, Weight 2.77 ± .60, RBS 6.57 ± 7.38. Among the asphyxiated neonates blood sugar levels in arterial cord blood were significantly lower and had a negative (r=−0.195, P

Perinatal hypoxia ischemia (HI) is a significant cause of brain injury in surviving infants. Although hypothermia improves outcomes in some infants, additional therapies are needed since about 40% of infants still have a poor outcome. Acetyl-L-carnitine (ALCAR), an acetylated derivative of L-carnitine, protected against early changes in brain metabolites and mitochondrial function after HI on postnatal day (PND) 7 in a rat pup model of near-term HI injury. However, its efficacy in long-term structural and functional outcomes remains unexplored. We determined the efficacy of ALCAR therapy administered to rat pups after HI at PND 7, using both longitudinal in vivo magnetic resonance imaging and behavioral tests, in male and female rats. HI led to sex-specific behavioral impairment, with males exhibiting more global functional deficits than females. Interestingly, HI reduced the volume of the contralateral hemisphere in males only, suggesting that the brain injury is more diffuse in males than in females. Treatment with ALCAR improved both morphological and functional outcomes in both male and female rats. These results suggest that ALCAR may be a potential therapy for clinical use since the treatment attenuated the moderate injury produced under the experimental conditions used and improved the functional outcome in preclinical studies.

Valentina Vio,1,2 Ana L Riveros,1 Andrea Tapia-Bustos,2 Carolyne Lespay-Rebolledo,2 Ronald Perez-Lobos,2 Luis Muñoz,3 Paola Pismante,3 Paola Morales,2,4 Eyleen Araya,5 Natalia Hassan,1,6 Mario Herrera-Marschitz,2 Marcelo J Kogan1,7 1Department of Pharmacological and Toxicology Chemistry, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile; 2Program of Molecular and Clinical Pharmacology, Medical Faculty, Universidad de Chile, Santiago, Chile; 3Chemical Meteorology Section, Comisión Chilena de Energía Nuclear, Santiago, Chile; 4Department of Neuroscience, Faculty of Medicine, Universidad de Chile, Santiago, Chile; 5Departamento de Ciencias Quimicas, Facultad de Ciencias Exactas, Universidad Andres Bello, Santiago, Chile; 6Programa Institucional de Fomento a la Investigación, Desarrollo e Innovación, Universidad Tecnológica Metropolitana, Santiago,Chile; 7Advanced Center for Chronic Diseases (ACCDiS), Santiago, Chile Background: Perinatal asphyxia interferes with neonatal development, resulting in long-term deficits associated with systemic and neurological diseases. Despite the important role of poly (ADP-ribose) polymerase 1 (PARP-1) in the regulation of gene expression and DNA repair, overactivation of PARP-1 in asphyxia-exposed animals worsens the ATP-dependent energetic crisis. Inhibition of PARP-1 offers a therapeutic strategy for diminishing the effects of perinatal asphyxia. Methods: We designed a nanosystem that incorporates a specific siRNA for PARP-1 knockdown. The siRNA was complexed with gold nanorods (AuNR) conjugated to the peptide CLPFFD for brain targeting. Results: The siRNA was efficiently delivered into PC12 cells, resulting in gene silencing. The complex was administered intraperitoneally in vivo to asphyxia-exposed rat pups, and the ability of the AuNR-CLPFFD/siRNA complex to reach the brain was demonstrated. Conclusion: The combination of a nanosystem for delivery and a specific siRNA for gene silencing resulted in effective inhibition of PARP-1 in vivo. Keywords: neonatal hypoxia, siRNA delivery, PARP-1 knockdown, gold nanorods, in vivo administration, PC12, rats

Objective: The objective of this pilot study was to start evaluating the efficacy and the safety (i.e., carboxyhemoglobin concentration of carbon monoxide (CO)) as a putative neuroprotective therapy in neonates. Study Design: Neonatal C57BL/6 mice were exposed to CO at a concentration of either 200 or 250 ppm for a period of 1 h. The pups were then sacrificed at 0, 10, 20, 60, 120, 180, and 240 min after exposure to either concentration of CO, and blood was collected for analysis of carboxyhemoglobin. Following the safety study, 7-day-old pups underwent a unilateral carotid ligation. After recovery, the pups were exposed to a humidified gas mixture of 8% oxygen and 92% nitrogen for 20 min in a hypoxia chamber. One hour after the hypoxia exposure, the pups were randomized to one of two groups: air (HI+A) or carbon monoxide (HI+CO). An inhaled dose of 250 ppm of CO was administered to the pups for 1 h per day for a period of 3 days. At 7 days post-injury, the pups were sacrificed and the brains analyzed for cortical and hippocampal volumes. Results: CO exposure at 200 and 250 ppm produced a peak carboxyhemoglobin concentration of 21.52 ± 1.18% and 27.55 ± 3.58%, respectively. The carboxyhemoglobin concentrations decreased rapidly, reaching control concentrations by 60 min post exposure. At 14 days of age (7 days post injury), the HI+CO (treated with 1 h per day of 250 ppm of CO for 3 days post injury) had significant preservation of the ratio of ipsilateral to contralateral cortex (median 1.07, 25% 0.97, 75% 1.23, n = 10) compared the HI+A group (p < 0.05). Conclusion: CO exposure of 250 ppm did not reach carboxyhemoglobin concentrations which would induce acute neurologic abnormalities and was effective in preserving cortical volumes following hypoxic-ischemic injury.

Se realizó un estudio retrospectivo parcial, longitudinal, comparativo, observacional evaluando a 2155 recién nacidos de un total de 18808, cuyo parto ocurrió entre enero de 1984 y diciembre de 1987 en el Hospital Nacional Cayetano Heredia. La incidencia de recién nacido pretérmino (RNPT) fue 4,92 % y la de bajo peso de (RNBP) 7,4%. De estos, 4,7% correspondieron a recién nacidos pretérmino de bajo peso (RNPBP). El riesgo de un nacimiento pretérmino de bajo peso, se ve influenciado por factores demográficos (paridad, grado de instrucción), antecedentes maternos (mala historia obstétrica, prematuros, toxemia e hipertensión) y complicaciones de la gestación actual. Entre las complicaciones médicas asociadas a la gestación destacaron la desnutrición, anemia e infecciones intercurrentes. Los recién nacidos pretérmino de bajo peso, se asocian significativamente a las gestaciones de mayor riesgo obstétrico, sin control prenatal a una elevada incidencia de hipoxia neonatal severa, así como a mayores tasas de morbilidad y mortalidad perinatal

Finding risk factors in pregnancy related to neonatal hypoxia is a challenging task due to the informal nature and a wide scatter of the data. In this work, we propose a methodology for sequential estimation of interestingness of association rules with two sets of criteria. The rules suggest that a strong relationship exists between the specific sets of attributes and the diagnosis. We set up a profile of the pregnant woman with a high likelihood of hypoxia of the newborn that would be beneficial to medical professionals.

Objective: To describe the value of HBO in the acute management of neonatal hypoxia (hypoxic–ischemic encephalopathy) and necrotizing enterocolitis.

Hypoxia-ischemia (HI) is a model of cerebral ischemia used to model neonatal hypoxia and to study brain damage. Interpreting the results of experiments that use HI rests partly on the assumption that only the brain suffers major damage. In this study, we demonstrate that HI also has adverse consequences on the heart. Both infarction scoring and measurements of troponin I indicate cardiac damage subsequent to HI. These results indicate that the effects of HI on the heart may confound the interpretation of experiments that have used HI to study neuroprotection or other aspects of brain damage.

BACKGROUND Hypoxic preconditioning (HPc) protects the neonatal brain in the setting of hypoxia-ischemia (HI). The mechanisms of protection may depend on activation of hypoxia inducible factor (HIF-1α). The present study sought to clarify the role of HIF-1α after HPc and HI. METHODS To induce HPc, HIF-1α knockout and wildtype mice were exposed to hypoxia at postnatal day 6. At day 7, the mice underwent HI. Brain injury was determined by histology. HIF-1α, downstream targets, and markers of cell death were measured by Western blot. RESULTS HPc protected the wildtype brain compared to wildtype without HPc, but did not protect the HIF-1α knockout brain. In wildtype, HIF-1α increased after hypoxia and after HI, but not with HPc. The HIF-1α knockout showed no change in HIF-1α after hypoxia, HI, or HPc/HI. After HI, spectrin 145/150 was higher in HIF-1α knockout, but after HPc/HI, it was higher in wildtype. LAMP2 was higher in wildtype early after HI, but not later. After HPc/HI, LAMP2 was higher in HIF-1α knockout. CONCLUSION These results indicate that HIF-1α is necessary for HPc protection in the neonatal brain, and may affect cell death after HI. Different death and repair mechanisms depend on the timing of HPc.

Despite its poor outcomes, therapeutic hypothermia (TH) is the current standard treatment for neonatal hypoxic-ischaemic encephalopathy (HIE). In this study, due to its antioxidant, anti-inflammatory, and antiapoptotic properties, the effectiveness of molecular hydrogen (H2) combined with TH was evaluated by means of neurological and histological assessments. Piglets were divided into three groups: hypoxic-ischaemic insult with normothermia (NT), insult with hypothermia (TH, 33.5 ± 0.5 °C), and insult with hypothermia with H2 ventilation (TH-H2, 2.1–2.7%). H2 ventilation and TH were administered for 24 h. After ventilator weaning, neurological assessment was performed every 6 h for 5 days. On day 5, the brains of the piglets were harvested for histopathological analysis. Regarding the neurological score, the piglets in the TH-H2 group consistently had the highest score from day 2 to 5 and showed a significantly higher neurological score from day 3 compared with the NT group. Most piglets in the TH-H2 group could walk at day 3 of recovery, whereas walking ability was delayed in the two other groups. The histological results revealed that TH-H2 tended to improve the status of cortical gray matter and subcortical white matter, with a considerable reduction in cell death. In this study, the combination of TH and H2 improved short-term neurological outcomes in neonatal hypoxic-ischaemic piglets.

Purpose To investigate if frequency-dependent contrasts using oscillating gradient diffusion MRI (dMRI) can detect hypoxia–ischemia (HI) -induced neurodegeneration in the neonatal mouse hippocampus. Methods Pulsed- and oscillating-gradient dMR images (at 50, 100, and 150 Hz) were acquired from postmortem fixed brains of mice exposed to neonatal HI using the Rice-Vanucci model. MRI data were acquired at 1, 4, and 8 days following HI, and compared with histological data from the same mice for in situ histological validation of the MRI findings. Results The rate of change of apparent diffusion coefficient with gradient frequency (ΔfADC) revealed unique layer-specific contrasts in the neonatal mouse hippocampus. ΔfADC measurements were found to show a significant decrease in response to neonatal HI injury, in the pyramidal (Py) and granule (GrDG) cell layers compared with contralateral regions. The areas of reduced intensity in the ΔfADC maps corresponded to regional neurodegeneration seen with H&E and Fluoro-Jade C stainings, indicating that alterations in ΔfADC contrasts are sensitive to early microstructural changes due to HI-induced neurodegeneration in the studied regions. Conclusion The findings show that the frequency-dependence of ADC measurements with oscillating-gradient dMRI can provide a sensitive contrast to detect HI-induced neurodegeneration in neuronal layers of the neonatal mouse hippocampus. Magn Reson Med 72:829–840, 2014. © 2013 Wiley Periodicals, Inc.

It is believed that neonatal hypoxia–ischemia (HI) brain injury causes neuron loss and brain functional defects. However, the effect of HI brain injury on dendritic development of the remaining pyramidal cells of the hippocampus and the reaction of contralateral hippocampal neurons require further studies. The Morris water maze and Golgi–Cox staining were used to evaluate the learning and memory and dendritic morphology of pyramidal cells. The results of Golgi–Cox staining showed CA1 pyramidal neurons of HI injury models with fewer bifurcations and shorter dendrite length than the naive control group. The density of dendritic spines of hippocampal CA1 pyramidal neurons was significantly lower in the HI brain injury group than in controls. With respect to hippocampal function, the HI brain injury group presented cognitive deficits in the reference memory task and probe trail. In the HI group, the pyramidal cells of left hippocampus that did not experienced ischemia but did experience hypoxia had more complex dendrites and higher density of spine than the HI injury side and control. The functional implementation of injured hippocampus might depend mainly on the hypertrophy of contralateral hippocampus after HI brain injury. Corticosterone can partially prevent the hippocampal pyramidal cells from HI injury and reduce the difference of the bilateral hippocampus pyramidal cells, but there was no improvement in learning and memory. © 2013 Wiley Periodicals, Inc.

Neonatal hypoxia-ischemia (HI) affects 60% of low birth weight infants and up to 40% of preterm births. Cell death and brain injury after HI have been shown to cause long-lasting behavioral deficits. By using a battery of behavioral tests on second generation 3-week-old rodents, we found that neonatal HI is associated with behavioral outcomes in the progeny of HI-affected parents. Our results suggest an epigenetic transfer mechanism of some of the neurological symptoms associated with neonatal HI. Elucidating the transfer of brain injury to the next generation after HI calls attention to the risks associated with HI injury and the need for proper treatment to reverse these effects. Assessing the devastating extent of HI's reach serves as a cautionary tale to the risks associated with neonatal HI, and provides an incentive to create improved therapeutic measures to treat HI.

Background: Neonatal encephalopathy induced by perinatal asphyxia is a serious condition associated with high mortality and morbidity. Inflammation after the insult is thought to contribute to brain injury. This inflammatory response to hypoxia-ischemia (HI) may not only occur in the brain but also in peripheral organs. The aim of the present study was to investigate the effect of neonatal HI on the inflammatory response in the liver in comparison to inflammation in the brain. Methods: HI was induced in P7 Wistar rats by unilateral carotid artery occlusion and hypoxia. Cytokine and chemokine mRNA levels were determined in the brain and liver by quantitative PCR. Polarization of brain macrophages to the M1/M2-like phenotype and infiltration of neutrophils were characterized by immunohistochemistry. Results: 3 h after HI, an upregulation of the proinflammatory cytokines TNF-α and IL-1β and anti-inflammatory IL-10 was observed in the ipsilateral hemisphere of the brain compared to mRNA levels in sham-operated animals. Additionally, cerebral CINC-1 and MCP-1 mRNA expressions were increased. We also observed increased numbers of macrophages/microglia of the M1-like phenotype as well as a small increase in granulocyte influx in the ipsilateral hemisphere. Conversely, in the liver 3 h after HI, a downregulation of TNF-α, IL-1β, and MCP-1 and a trend towards an upregulation of IL-10 were observed compared to mRNA levels of sham-operated animals. However, hepatic CINC-1 expression was increased compared to levels in sham-operated animals. Following systemic hypoxia only, no significant changes in the expression of TNF-α, CINC-1 or MCP-1 were observed in the liver compared to sham-operated littermates, except for an upregulation in hepatic IL-1β expression 3 h after hypoxia. Twenty-four hours after insult, cerebral ipsilateral TNF-α, MCP-1 and CINC-1 mRNA expression was still increased, together with an increase in TGF-β expression. Moreover, an increase in macrophages/microglia of the M1-like phenotype was observed together with the appearance of macrophages/microglia of the M2-like phenotype around the cerebral lesion as well as an increase in granulocyte influx in comparison to 3 h after HI. In the liver, 24 h after HI, cytokine and chemokine responses were similar to mRNA levels in sham-operated animals except for a decrease in IL-10 and MCP-1. Conclusion: We describe for the first time that brain damage following neonatal HI induces an early downregulation of the proinflammatory response in the liver. HI induces an early proinflammatory response in the brain with a concomitant increase in influx of neutrophils and polarization of macrophages/microglia to the M1-like phenotype starting at 3 h and increasing up to 24 h after HI. The inflammatory state of the brain changes after 24 h, with an increase in the anti-inflammatory cytokine TGF-β together with the appearance of macrophages/microglia of the M2-like phenotype. The downregulation of proinflammatory cytokines in the liver is not due to systemic hypoxia only, but is induced by the cerebral damage.

Neonatal hypoxic ischemic injury (HII) is a devastating brain disease for which hypothermia is currently the only approved treatment. As new therapeutic interventions emerge there is a significant need for noninvasive objective quantification of the spatiotemporal lesion dynamics combined with precise information about lesion constituents (ischemic core and penumbra). These metrics are important for deciding treatment parameters (type, time, site, and dose) and for monitoring injury-therapy interactions. Such information provided ‘on-line’ in a timely fashion to the clinician could revolutionize clinical management. Like other spatiotemporal biological processes, video bioinformatics can assist objective monitoring of injury–therapy interactions. We have been studying the efficacy of various potential treatments in translational (rodent) HII models using magnetic resonance imaging (MRI). We have developed a novel computational tool, hierarchical region splitting (HRS) to rapidly identify ischemic lesion metrics. HRS detects similar lesion volumes compared to manual detection methods and is fast, robust, and reliable compared to other computational methods. HRS also provides additional information about the location, size, and evolution of the core and penumbra, which are difficult to ascertain with manual methods. This chapter summarizes the ability of HRS to identify lesion dynamics and ischemic core-penumbra evolution following neonatal HII. In addition, we demonstrate that HRS provides information about lesion dynamics following different therapies (e.g., hypothermia, stem cell implantation). Our findings show that computational analysis of MR images using HRS provides novel quantitative approaches that can be applied to clinical and translational stroke research using data mining of standard experimental and clinical MRI data.

Hypoxia is the most common cause of neonatal seizures and can lead to epilepsy, but the epileptogenic mechanisms are not yet understood. We have previously shown that hypoxia-induced seizures in the neonatal rat result in acutely decreased amplitudes and frequency of spontaneous and miniature inhibitory postsynaptic currents (sIPSCs and mIPSCs) in hippocampal CA1 pyramidal neurons. In the current study, we asked whether such changes persist for several days following hypoxia-induced seizures. Similar to the acute findings, we observed decreased frequency and amplitudes of sIPSCs and decreased mIPSC amplitudes in CA1 pyramidal neurons at 3–5 days after hypoxia. However, in contrast to the acute findings, we observed no differences between hypoxia-treated and control groups in mIPSC frequency. Additionally, by 7 days after hypoxia, sIPSC amplitudes in the hypoxia group had recovered to control levels, but sIPSC frequency remained decreased. These data indicate that the persistently decreased sIPSC frequency result from decreased firing of presynaptic inhibitory interneurons, with only transient possible changes in postsynaptic responses to GABA release.

A participação de marcadores bioquímicos na avaliação de quadros de asfixia neonatal é cada vez mais relevante. A proteína S100B é de particular importância neste campo. O objetivo deste estudo foi procurar destacar a importância da proteína S100B na avaliação de recém-nascidos a termo com quadro de encefalopatia hipóxico-isquêmica, assim como correlacionar com outras substâncias que também participam do processo isquêmico. Foram analisados 21 casos de recém nascidos a termo que desenvolveram encefalopatia hipóxico-isquêmica no período de setembro de 2003 a outubro de 2004. Realizadas coletas no 1º e 4º dia de vida e dosadas, por método imunocitoquímico, a proteína S100B e o lactato. Observouse correlação positiva entre as duas substâncias, assim como quando comparadas entre si nas suas respectivas dosagens, obteve-se significância estatística. Biochemical markers have played an increasingly relevant role in the assessment of neonatal asphyxia. The S100B protein is particularly important in re s e a rch conducted in this field. The purpose of this study was to underline the importance of the S100B protein in the assessment of term newborn infants with hypoxic-ischemic encephalopathy, as well as to relate it to other substances also involved in the ischemic p rocess. An assessment was made from September 2003 to October 2004 of 21 term newborn infants who developed hypoxic-ischemic encephalopathy. Samples were collected on the 1st and 4th day of life and S100B p rotein and lactate concentrations were calculated using the immune cytochemical method. A positive relationship was found between the two substances. Additionally, a comparison between the two substances showed a statistically significant correlation.

Neonatal hypoxia increases aldosterone production and plasma lipids. Because fatty acids can inhibit aldosterone synthesis, we hypothesized that increases in plasma lipids restrain aldosteronogenesis in the hypoxic neonate. We exposed rats to 7 days of hypoxia from birth to 7 days of age (suckling) or from 28 to 35 days of age (weaned at day 21). Plasma was analyzed for lipid content, and steroidogenesis was studied in dispersed whole adrenal glands untreated and treated to wash away lipids. Hypoxia increased plasma cholesterol, triglycerides, and nonesterified fatty acids in the suckling neonatal rat only. Washing away lipids increased aldosterone production in cells from 7-day-old rats exposed to hypoxia, but not in cells from normoxic 7-day-old rats or from normoxic or hypoxic 35-day-old rats. Addition of oleic or linolenic acid to washed cells inhibited both aldosterone and corticosterone production, although cells from hypoxic 7-day-old rats were less sensitive. We conclude that hypoxia induces hyperlipidemia in the suckling neonate and that elevated nonesterified fatty acids inhibit aldosteronogenesis.

Seizures after neonatal hypoxia are difficult to treat. A recent antiepileptic safety and dose-finding study examined phenobarbital plus bumetanide, but was stopped owing to apparent futility and increased risk of hearing loss. However, this decision could have been overcautious: 0.2 mg/kg bumetanide reduced seizure burden, and might not have increased hearing loss.

BackgroundHypoxic-ischemic (HI) injury to the developing brain remains a major cause of morbidity. Hypothermia is effective but does not provide complete neuroprotection, prompting a search for adjunctive therapies. Erythropoietin (Epo) has been shown to be beneficial in several models of neonatal HI. This study examines combination hypothermia and treatment with erythropoietin in neonatal rat HI.MethodsRats at postnatal day 7 were subjected to HI (Vannucci model) and randomized into four groups: no treatment, hypothermia alone, Epo alone, or hypothermia and Epo. Epo (1,000 U/kg) was administered in three doses: immediately following HI, and 24 h and 1 wk later. Hypothermia consisted of whole-body cooling for 8 h. At 2 and 6 wk following HI, sensorimotor function was assessed via cylinder-rearing test and brain damage by injury scoring. Sham-treated animals not subjected to HI were also studied.ResultsDifferences between experimental groups, except for Epo treatment on histopathological outcome in males, were not statistically significant, and combined therapy had no adverse effects.ConclusionNo significant benefit was observed from treatment with either hypothermia or combination therapy. Future studies may require older animals, a wider range of functional assays, and postinsult assessment of injury severity to identify only moderately damaged animals for targeted therapy.

We investigated whether the effect of neonatal hypoxia on amphetamine-induced hyperlocomotion can reproduce the ontogenic (age of onset) properties of schizophrenia. Neonatal hypoxia enhanced amphetamine-induced hyperlocomotion in adult mice and decreased it in adolescent mice. These findings provide ontogenic validity for this very simple animal model of schizophrenia.

The NaKCl cotransporter NKCC1 facilitates intraneuronal chloride accumulation in the developing brain. Bumetanide, a clinically available diuretic, inhibits this chloride transporter, and augments the antiepileptic effects of phenobarbital in neonatal rodents. In a neonatal cerebral hypoxia-ischemia (HI) model, elicited by right carotid ligation, followed by 90 min 8% O2 exposure in 7-day-old(P7) rats, phenobarbital(PB) increases the neuroprotective efficacy of hypothermia. We evaluated whether bumetanide influenced the neuroprotective efficacy of combination treatment with PB and hypothermia(HT). P7 rats underwent HI lesioning; 15 min later, all received PB (30 mg/kg). 10 min later, half received bumetanide (10 mg/kg, PB-HT+BUM) and half received saline (PB-HT+SAL). One hour after HI, all were cooled (30°C, 3h). Contralateral forepaw sensorimotor function and brain damage were evaluated 1 to 4 weeks later. Forepaw functional measures were close to normal in the PB-HT+BUM group, while deficits persisted in PB-HT+SAL controls; there were corresponding reductions in right cerebral hemisphere damage (at P35, % damage: PB-HT+BUM, 21±16 versus 38±20 in controls). These results provide evidence that NKCC1 inhibition amplifies phenobarbital bioactivity in the immature brain, and suggest that co-administration of phenobarbital and bumetanide may represent a clinically feasible therapy to augment the neuroprotective efficacy of therapeutic hypothermia in asphyxiated neonates.