Early and mid-gestation Zika virus (ZIKV) infection in the olive baboon (Papio anubis) leads to fetal CNS pathology by term gestation

Zika virus (ZIKV) infection in pregnancy can produce catastrophic teratogenic damage to the developing fetus including microcephaly and congenital Zika syndrome (CZS). We previously described fetal CNS pathology occurring by three weeks post-ZIKV inoculation in Olive baboons at mid-gestation, including neuroinflammation, loss of radial glia (RG), RG fibers, neuroprogenitor cells (NPCs) resulting in disrupted NPC migration. In the present study, we explored fetal brain pathologies at term gestation resulting from ZIKV exposure during either first or second trimester in the Olive baboon. In all dams, vRNA in whole blood resolved after 7 days post inoculation (dpi). One first trimester infected dam aborted at 5 dpi. All dams developed IgM and IgG response to ZIKV with ZIKV IgG detected in fetal serum. Placental pathology and inflammation were observed including disruption of syncytiotrophoblast layers, delayed villous maturation, partially or fully thrombosed vessels, calcium mineralization and fibrin deposits. In the uterus, ZIKV was detected in ¾ first trimester but not in second trimester infected dams. While ZIKV was not detected in any fetal tissue at term, all fetuses exhibited varying degrees of neuropathology. Fetal brains from ZIKV inoculated dams exhibited a range of gross brain pathologies including irregularities of the major gyri and sulci of the cerebral cortex and cerebellar pathology. Frontal cortices of ZIKV fetuses showed a general disorganization of the six-layered cortex with degree of disorganization varying among the fetuses from the two groups. Frontal cortices from ZIKV inoculation in the first but not second trimester exhibited increased microglia, and in both trimester ZIKV inoculation, increased astrocyte numbers (white matter). In the cerebellum, increased microglia were observed in fetuses from both first and second trimester inoculation. In first trimester ZIKV inoculation, decreased oligodendrocyte precursor cell populations were observed in fetal cerebellar white matter. In general, our observations are in accordance with those described in human ZIKV infected fetuses.

Long term hypoxia during gestation alters perirenal adipose tissue gene expression in the lamb

We previously reported that following long-term hypoxia (LTH), the ovine foetus exhibits enhanced expression of brown/beige adipose genes. This study was designed to determine if these changes are preserved after birth. Pregnant ewes were divided among three groups, 1) Control, sea level, 2) LTH, high altitude (3,820 m, LTH-HA) from ~ day 40 of gestation through ~14 days post-delivery and 3) LTH from ⁓ day 40 through day 137 of gestation then returned to the laboratory where atory reduced maternal PO₂ was maintained by nitrogen infusion. Following delivery, lambs remained at sea level (LTH-SL). Perirenal adipose tissue was collected at ~day 14, and qRT-PCR was used to quantify mRNA. Uncoupling protein 1 (UCP-1), PPAR gamma coactivator 1 (PGC1α), and deiodinase-2 (DIO2) mRNA levels were significantly lower in both LTH groups while PR domain containing 16 (PRDM16) levels did not differ. Peroxisome proliferator-activated receptor (PPARγ) was maintained in the LTH-HA group and significantly increased in the LTH-SL group, compared to control. Unlike our previous LTH foetal studies, the brown/beige fat phenotype was rapidly lost by day 14 postpartum compared to control, while PPARγ was maintained. This loss of the brown fat phenotype may promote obesity due to decreased energy expenditure, favouring fat deposition.

Zika virus infection at mid-gestation results in fetal cerebral cortical injury and fetal death in the olive baboon

Zika virus (ZIKV) infection during pregnancy in humans is associated with an increased incidence of congenital anomalies including microcephaly as well as fetal death and miscarriage and collectively has been referred to as Congenital Zika Syndrome (CZS). Animal models for ZIKV infection in pregnancy have been developed including mice and non-human primates (NHPs). In macaques, fetal CZS outcomes from maternal ZIKV infection range from none to significant. In the present study we develop the olive baboon (Papio anubis), as a model for vertical transfer of ZIKV during pregnancy. Four mid-gestation, timed-pregnant baboons were inoculated with the French Polynesian ZIKV isolate (10⁴ ffu). This study specifically focused on the acute phase of vertical transfer. Dams were terminated at 7 days post infection (dpi; n = 1), 14 dpi (n = 2) and 21 dpi (n = 1). All dams exhibited mild to moderate rash and conjunctivitis. Viremia peaked at 5–7 dpi with only one of three dams remaining mildly viremic at 14 dpi. An anti-ZIKV IgM response was observed by 14 dpi in all three dams studied to this stage, and two dams developed a neutralizing IgG response by either 14 dpi or 21 dpi, the latter included transfer of the IgG to the fetus (cord blood). A systemic inflammatory response (increased IL2, IL6, IL7, IL15, IL16) was observed in three of four dams. Vertical transfer of ZIKV to the placenta was observed in three pregnancies (n = 2 at 14 dpi and n = 1 at 21 dpi) and ZIKV was detected in fetal tissues in two pregnancies: one associated with fetal death at ~14 dpi, and the other in a viable fetus at 21 dpi. ZIKV RNA was detected in the fetal cerebral cortex and other tissues of both of these fetuses. In the fetus studied at 21 dpi with vertical transfer of virus to the CNS, the frontal cerebral cortex exhibited notable defects in radial glia, radial glial fibers, disorganized migration of immature neurons to the cortical layers, and signs of pathology in immature oligodendrocytes. In addition, indices of pronounced neuroinflammation were observed including astrogliosis, increased microglia and IL6 expression. Of interest, in one fetus examined at 14 dpi without detection of ZIKV RNA in brain and other fetal tissues, increased neuroinflammation (IL6 and microglia) was observed in the cortex. Although the placenta of the 14 dpi dam with fetal death showed considerable pathology, only minor pathology was noted in the other three placentas. ZIKV was detected immunohistochemically in two placentas (14 dpi) and one placenta at 21 dpi but not at 7 dpi. This is the first study to examine the early events of vertical transfer of ZIKV in a NHP infected at mid-gestation. The baboon thus represents an additional NHP as a model for ZIKV induced brain pathologies to contrast and compare to humans as well as other NHPs.

Zika virus is endemic in the Americas, primarily spread through mosquitos and sexual contact. Zika virus infection during pregnancy in women is associated with a variety of fetal pathologies now referred to as Congenital Zika Syndrome (CZS), with the most severe pathology being fetal microcephaly. Developing model organisms that faithfully recreate Zika infection in humans is critical for future development of treatments and preventions. In our present study, we infected Olive baboons at mid-gestation with Zika virus and studied the acute period of viremia and transfer of Zika virus to the fetus during the first three weeks after infection to better understand the timing and mechanisms of transfer of ZIKV across the placenta, leading to CZS. We observed Zika virus transfer to fetuses resulting in fetal death in one pregnancy and in a second pregnancy, significant damage to the frontal cortex of the fetal brain at a critical period of neurodevelopment in primates. Thus, the baboon provides a promising new non-human primate model to further compare and contrast the consequences of Zika virus infection in pregnancy to humans and other non-human primates.

Dietary practices in propionic acidemia: A European survey

Background

The definitive dietary management of propionic acidaemia (PA) is unknown although natural protein restriction with adequate energy provision is of key importance.

Aim

To describe European dietary practices in the management of patients with PA prior to the publication of the European PA guidelines.

Methods

This was a cross-sectional survey consisting of 27 questions about the dietary practices in PA patients circulated to European IMD dietitians and health professionals in 2014.

Results

Information on protein restricted diets of 186 PA patients from 47 centres, representing 14 European countries was collected. Total protein intake [PA precursor-free L-amino acid supplements (PFAA) and natural protein] met WHO/FAO/UNU (2007) safe protein requirements for age in 36 centres (77%). PFAA were used to supplement natural protein intake in 81% (n = 38) of centres, providing a median of 44% (14–83%) of total protein requirement. Seventy-four per cent of patients were prescribed natural protein intakes below WHO/FAO/UNU (2007) safe levels in one or more of the following age groups: 0–6 m, 7–12 m, 1–10 y, 11–16 y and > 16 y. Sixty-three per cent (n = 117) of patients were tube fed (74% gastrostomy), but only 22% received nocturnal feeds.

Conclusions

There was high use of PFAA with intakes of natural protein commonly below WHO/FAO/UNU (2007) safe levels. Optimal dietary management can only be determined by longitudinal, multi-centre, prospective case controlled studies. The metabolic instability of PA and small patient cohorts in each centre ensure that this is a challenging undertaking.

Gestational hypoxia disrupts the neonatal leptin surge and programs hyperphagia and obesity in male offspring in the Sprague-Dawley rat

The effect of gestational hypoxia on the neonatal leptin surge, development of hypothalamic arcuate nuclei (ARH) projections and appetite that could contribute to the programming of offspring obesity is lacking. We examined the effect of 12% O₂ from gestational days 15–19 in the Sprague-Dawley rat on post-weaning appetite, fat deposition by MRI, adipose tissue cytokine expression, the neonatal leptin surge, ARH response to exogenous leptin, and αMSH projections to the paraventricular nucleus (PVN) in response to a high fat (HFD) or control diet (CD) in male offspring. Normoxia (NMX) and Hypoxia (HPX) offspring exhibited increased food intake when fed a HFD from 5–8 weeks post-birth; HPX offspring on the CD had increased food intake from weeks 5–7 vs. NMX offspring on a CD. HPX offspring on a HFD remained hyperphagic through 23 weeks. Body weight were the same between offspring from HPX vs. NMX dams from 4–12 weeks of age fed a CD or HFD. By 14–23 weeks of age, HPX offspring fed the CD or HFD as well as male NMX offspring fed the HFD were heavier vs. NMX offspring fed the CD. HPX offspring fed a CD exhibited increased abdominal adiposity (MRI) that was amplified by a HFD. HPX offspring fed a HFD exhibited the highest abdominal fat cytokine expression. HPX male offspring had higher plasma leptin from postnatal day (PN) 6 through 14 vs. NMX pups. HPX offspring exhibited increased basal c-Fos labeled cells in the ARH vs. NMX pups on PN16. Leptin increased c-Fos staining in the ARH in NMX but not HPX offspring at PN16. HPX offspring had fewer αMSH fibers in the PVN vs. NMX offspring on PN16. In conclusion, gestational hypoxia impacts the developing ARH resulting in hyperphagia contributing to adult obesity on a control diet and exacerbated by a HFD.

Interaction Between Progesterone and Interleukin-1β in Modulating Progesterone Receptor Expression and the Inflammatory Phenotype in Human Cervical Fibroblasts

Progesterone helps maintain cervical structure during pregnancy via the progesterone receptor (PR). Two PR isoforms exist, PR-A and PR-B, which have overlapping as well as isoform-specific target genes. During late gestation, leukocytes infiltrate the cervical stroma accompanied by increased cervical cytokine levels, resembling an inflammatory process. We examined interleukin (IL)-1β regulation of the expression of PR-A, PR-B, and genes governing prostaglandin synthesis in human cervical fibroblasts (HCFs). Since progesterone has been shown to exert anti-inflammatory actions, we also examined the capacity of progesterone (R5020) to ameliorate the actions of IL-1β in HCFs. Interleukin-1β induced both PR-A and PR-B mRNA in HCFs. Interleukin-1β induced a rapid and transient loss of both PR-A and PR-B protein, followed by a latent (24 hours) increase in both PR isoforms. R5020 negated the IL-1β-induced increase in PR-A and PR-B mRNA and protein as well as the rapid IL-1β-induced downregulation of nuclear PR. Interleukin-1β induced prostaglandin G/H synthase-2 (PGHS-2), but not prostaglandin G/H synthase-1 (PGHS-1), as well as prostaglandin E synthase-1 (PGES-1), but not prostaglandin F synthase (PGFS). R5020 did not ameliorate IL-1β induction of PGHS-2 or PGES-1. Blockade of prostaglandin synthesis (indomethacin) prevented both the IL-1β-induced increase in PR mRNA and the acute decrease in PR-A and PR-B protein, implicating a role for prostaglandins in regulating PR expression in HCFs. Although progesterone may function to maintain PR expression in a milieu of increasing cytokines in the late gestation human cervix, it does not exert an anti-inflammatory role with regard to prostaglandin E₂ (PGE2) production.

Dietary practices in isovaleric acidemia: A European survey

Background

In Europe, dietary management of isovaleric acidemia (IVA) may vary widely. There is limited collective information about dietetic management.

Aim

To describe European practice regarding the dietary management of IVA, prior to the availability of the E-IMD IVA guidelines (E-IMD 2014).

Methods

A cross-sectional questionnaire was sent to all European dietitians who were either members of the Society for the Study of Inborn Errors of Metabolism Dietitians Group (SSIEM-DG) or whom had responded to previous questionnaires on dietetic practice (n = 53). The questionnaire comprised 27 questions about the dietary management of IVA.

Results

Information on 140 patients with IVA from 39 centres was reported. 133 patients (38 centres) were given a protein restricted diet. Leucine-free amino acid supplements (LFAA) were routinely used to supplement protein intake in 58% of centres. The median total protein intake prescribed achieved the WHO/FAO/UNU [2007] safe levels of protein intake in all age groups. Centres that prescribed LFAA had lower natural protein intakes in most age groups except 1 to 10 y. In contrast, when centres were not using LFAA, the median natural protein intake met WHO/FAO/UNU [2007] safe levels of protein intake in all age groups. Enteral tube feeding was rarely prescribed.

Conclusions

This survey demonstrates wide differences in dietary practice in the management of IVA across European centres. It provides unique dietary data collectively representing European practices in IVA which can be used as a foundation to compare dietary management changes as a consequence of the first E-IMD IVA guidelines availability.

Gestational hypoxia modulates expression of corticotropin-releasing hormone and arginine vasopressin in the paraventricular nucleus in the ovine fetus

Maturation of the fetal hypothalamo–pituitary–adrenocortical (HPA) axis is critical for organ maturation necessary for the fetus to transition to the ex‐utero environment. Intrauterine stressors can hasten maturation of the HPA axis leading to fetal growth restriction and in sheep, premature birth. We have previously reported that high‐altitude mediated, long‐term‐moderate gestational hypoxia (LTH) during gestation has a significant impact on the fetal HPA axis. Significant effects were observed at the level of both the anterior pituitary and adrenal cortex resulting in elevated plasma ACTH during late gestation with decreased adrenocortical expression of enzymes rate limiting for cortisol synthesis. As such, these fetuses exhibited the normal ontogenic rise in fetal plasma cortisol but an exaggerated cortisol response to acute stress. This study extended these findings to ACTH secretagogue expression in the PVN using in situ hybridization. We report that the expression of AVP but not CRH was increased in the medial parvocellular PVN (mpPVN) in the LTH fetus. This represented an increase in both AVP mRNA per neuron as well as an increase in AVP hybridizing neurons with no increase in mpPVN CRH neurons. LTH had no effect on PVN volume, area of CRH or AVP hybridization, thus LTH did not have a trophic effect on the size of the nucleus. In conclusion, there appears to be a switch from CRH to AVP as a primary ACTH secretagogue in response to LTH, supporting our previous findings of increased anterior pituitary sensitivity to AVP over CRH in the LTH fetus.

How strict is galactose restriction in adults with galactosaemia? International practice

Dietary management of 418 adult patients with galactosaemia (from 39 centres/12 countries) was compared. All centres advised lactose restriction, 6 restricted galactose from galactosides ± fruits and vegetables and 12 offal. 38% (n=15) relaxed diet by: 1) allowing traces of lactose in manufactured foods (n=13) or 2) giving fruits, vegetables and galactosides (n=2). Only 15% (n=6) calculated dietary galactose. 32% of patients were lost to dietetic follow-up. In adult galactosaemia, there is limited diet relaxation.

Long-Term Gestational Hypoxia Modulates Expression of Key Genes Governing Mitochondrial Function in the Perirenal Adipose of the Late Gestation Sheep Fetus

We previously reported that long-term hypoxia (LTH) increases expression of brown adipose tissue (BAT) genes in the perirenal adipose in the ovine fetus. The mechanisms with which hypoxia mediates the enhanced BAT phenotype are unresolved. This study was designed to examine the effects of LTH on (1) the expression of endothelial cell nitric oxide synthase (eNOS) and (2) indicators of mitochondrial biogenesis (transcription factors mitochondrial transcription factor A (mtTFA), nuclear respiratory factor (NRF) 1, and NRF-2; cytochrome c oxidase (COX) I, II, and IV and mitochondrial DNA content). Pregnant ewes were maintained at high altitude (3820 m) from ∼40 to 137 to 140 days of gestation and perirenal adipose was collected from normoxic control and LTH fetuses. There was no effect of LTH on fetal body weight or perirenal adipose mass. Long-term hypoxia increased (P < .05) perirenal eNOS and phospho-eNOS, messenger RNA (mRNA) for NRF1, NRF-2, mtTFA as well as COX-I, COX-II, and COX-IV mRNA. In contrast, mRNA for 2 markers for cellular proliferation (Ki67 and proliferating cell nuclear antigen [PCNA]) was lower in perirenal adipose from LTH fetuses compared to controls (P < .05), while mitochondrial to nuclear DNA ratio did not differ between groups. In conclusion, nitric oxide may function as a mechanism via which LTH enhances the BAT phenotype in fetal sheep prior to birth. Although there is an apparent increase in genes supporting mitochondrial function and adaptive thermogenesis in response to LTH, there does not appear to be an increased mitochondrial biogenesis per se. Such adaptive changes may provide a mechanism for the prominence of the BAT phenotype observed in the late gestation LTH fetus.

Leptin receptor antagonist treatment ameliorates the effects of long-term maternal hypoxia on adrenal expression of key steroidogenic genes in the ovine fetus

We previously reported elevated adipose leptin expression, plasma leptin concentrations, and adrenocortical leptin receptor expression in the long-term hypoxic (LTH) ovine fetus. This study addressed whether leptin antagonist (LA) administration to LTH fetal sheep altered expression of key genes governing cortisol synthesis. Ewes were maintained at high altitude (3,820 meters) from 40 to 130 days gestation (dG), returned to Loma Linda University, and implanted with a maternal tracheal catheter. Reduced Po2 was maintained by nitrogen infusion. On 132 dG, LTH (n = 11) and age-matched, normoxic control (n = 11) fetuses underwent vascular catheter implantation. At 138 dG, fetuses were continuously infused with either saline or the LA (1.5 mg·kg(-1)·day(-1)) for 4 days and samples collected for blood gases, ACTH, and cortisol. Fetal adrenal cortex was collected for determination of steriodogenic acute regulatory protein (StAR), ACTH, and leptin receptor, cholesterol side-chain cleavage (CYP11A1), cytochrome P-450 11β-hydroxylase (CYP11B1), 17α-hydroxylase (CYP17), 21-hydroxylase (CYP21), signal transducer and activator of transcription 3 (STAT3), pSTAT3, and 17β-hydroxysteroid dehydrogenase (HSD3B) expression. In the saline-infused LTH fetuses, StAR, ACTH receptor, CYP11A1, and CYP17 expression was significantly lower compared with control (P < 0.05), whereas levels of CYP11B1, CYP21, and HSD3B mRNA were similar between groups. LA infusion restored expression of StAR, pSTAT3, CYP11A1, and CYP17, but not ACTH receptor, to normal ontogenic levels in the LTH group while having no effect on control fetuses. Neither fetal plasma ACTH nor cortisol concentrations were altered by LA infusion. We speculate that while leptin plays a role in governing expression of key enzymes and StAR in response to LTH, other factors play a role in modulating cortisol synthesis in these fetuses.

Simultaneous genotyping of single nucleotide polymorphisms in the IL-6, IL-10, TNFalpha and TNFbeta genes

Single nucleotide polymorphisms (SNP) in the human IL-6, IL-10, TNFalpha and TNFbeta genes have been associated with gene function and susceptibility to disease. In this study, primers containing mismatches at 1-3 nucleotide positions were designed to incorporate a new restriction site recognized by endonucleases AlwNI, BcgI, BglI, BsaBI, BslI, BstXI, EcoNI or XcmI for genotyping SNPs in the IL-6 gene (position - 174), IL-10 gene (positions -592 and -1082), TNFalpha gene (positions -238, - 308 and -863) and TNFbeta gene (position + 249) by mismatched polymerase chain reaction and restriction fragment length polymorphism (PCR/RFLP). Our results show that appropriately designed BslI-based mismatched PCR/RFLP assays can be successfully used to determine the genotypes for approximately 40% of SNPs. The mismatched PCR strategy can be coupled with multiplex-amplification to enable simple and rapid determination of several SNP genotypes in a single reaction.

School-related issues among HIV-infected children

OBJECTIVE

Many children with human immunodeficiency virus (HIV) infection are surviving long enough to reach school age. This study describes issues related to school attendance and disclosure of HIV infection in a population of HIV-infected children.

METHODS

A statewide pediatric HIV surveillance system was used to collect data on school-age (>/=5 years old) HIV-infected children. In addition, HIV clinic nurses familiar with the child's history participated in a cross-sectional survey that collected information on school-related issues during the 1993-1994 school year.

RESULTS

Of the 92 school-age children, only 3 were too ill to attend school. Another 5 children were home-schooled. Of the 84 who attended school outside the home, 25% had severe symptoms of HIV infection (Centers for Disease Control and Prevention [CDC] clinical category C). Absence from school ranged from less than 2 weeks during the year for half of the children (51%) to more than 8 weeks for 9 children (12%). Twenty-nine percent of the children received medication in school, usually administered by the school nurse. Over two thirds of the 50 children ages 5 to 10 years had not been told that they had HIV infection. Only 1 of the 20 children more than 10 years of age was not aware of her HIV infection. For 53% of the children attending school, no school personnel had been informed of the child's HIV infection. Administration of HIV medications at school, age of child, and treatment at one particular HIV clinic were associated with the parents' decision to inform school personnel. In the 47% of cases where the school had been informed, school nurses were most frequently notified, followed by principals and teachers.

CONCLUSION

Only 3% of school-age children were too ill to attend school, and almost all were enrolled in public schools. The number of HIV-infected children reaching school age will continue to grow, and public schools will bear the responsibility for educating these children. Health care providers will increasingly be called upon for guidance by both educators and families to assure that HIV-infected children receive the best education possible.

In situ evidence for DNA fragmentation in Huntington's disease striatum and Alzheimer's disease temporal lobes

To test the hypothesis that apoptosis is involved in human brain neurodegenerative disorders, we investigated whether DNA fragmentation occurs in Alzheimer's disease (AD). Huntington's disease (HD) and Parkinson's disease, as well as in temporal lobe epilepsy, using neurologically normal post-mortem human brain tissue as a control. Using in situ end labelling of DNA, we found evidence of DNA fragmentation in cells in temporal cortex and hippocampus from patients with AD and in striatum from those with HD. In contrast, only scattered DNA fragmentation positive cells were detected in the pial surfaces of some of the neurologically normal human brains. Thus, cells in the HD striatum and AD temporal cortex exhibited DNA fragmentation, suggesting that apoptosis may be involved in these disorders.

MK-801 does not attenuate immediate-early gene expression following an amygdala afterdischarge

It has been suggested that the increased transient expression of immediate-early gene transcription factors seen in nerve cells following an afterdischarge may initiate longer lasting or permanent changes in gene expression which underly the development of kindling. Since the development of kindling is sensitive to pharmacological blockade of the N-methyl-D-aspartate receptor, we tested whether the increased expression of the immediate-early genes c-fos, jun-B, c-jun, krox-20, and krox-24 following a kindling afterdischarge was also sensitive to N-methyl-D-aspartate receptor blockade by MK-801. In this report we demonstrate that all five immediate-early genes are induced by an amygdala afterdischarge. N-methyl-D-aspartate receptor blockade by a dose of MK-801 that significantly retards the development of amygdala kindling failed to attenuate immediate-early gene expression. These results suggest that although expression of these five immediate-early genes occurs after an amygdala afterdischarge their expression is not involved in the N-methyl-D-aspartate receptor-mediated component of amygdala kindling.

The osmolarity of adult Drosophila hemolymph and its effect on oocyte-nurse cell electrical polarity

In ovarian follicles of Drosophila, changes in external osmolarity affect the steady-state potentials of oocytes more than those of nurse cells. Thus the osmolarity of the incubation medium affects the occurrence and the direction of an electrical gradient across the connecting intercellular bridges. At 255 mOsm nurse cell Em averaged 2.5 mV negative to oocyte Em (P < 0.001). At 275 and at 300 mOsm there was no significant difference between oocyte and nurse cell. At 400 mOsm nurse cell Em averaged 1.1 mV positive to oocyte Em (P = 0.007). The osmolarity of adult Drosophila hemolymph was measured by a variation of freezing point depression and averaged 251 +/- 9 (SE) mOsm. The measured osmolarity and measured ionic concentrations of adult Drosophila hemolymph were used to develop an incubation medium, which was used to incubate developing ovarian follicles. Electrical measurements made in this saline, which mimics in vivo conditions, confirmed reports of a nurse cell-oocyte electrical gradient, with nurse cell Em significantly more negative than oocyte Em. Microinjections of the negatively charged dye Lucifer yellow CH showed that this charged molecule accumulated in the oocyte at the in vivo osmolarity, and in the nurse cells at highly elevated osmotic levels.

Is c-Jun involved in nerve cell death following status epilepticus and hypoxic-ischaemic brain injury?

Neurons undergoing delayed neuronal death produced by hypoxia-ischaemia (HI) or status epilepticus (SE) showed a massive expression of c-Jun in their nuclei 24 h after the insult. With SE there was also a weaker induction of c-Fos and Jun B in dying neurons. SE induced in the presence of the NMDA antagonist MK-801 produced no delayed c-Jun expression in the hippocampus and nerve cell death did not occur in this region, although there was a delayed c-jun expression in the amygdala/piriform region, and cell death occurred in this area. Activation of central muscarinic receptors with pilocarpine, or block of D2 dopamine receptors with haloperidol, treatments which do not cause neuronal damage, strongly induced Fos and Jun B in hippocampal and striatal neurons, but only induced c-Jun very weakly. Thus, c-Jun may participate in the genetic cascade of events that produce programmed cell death in neurons.