Functional integration of new neurons into hippocampal networks and poststroke comorbidities following neonatal stroke in mice.

Stroke in the developing brain is an important cause of chronic neurological morbidities including neurobehavioral dysfunction and epilepsy. Here, we describe a mouse model of neonatal stroke resulting from unilateral carotid ligation that results in acute seizures, long-term hyperactivity, spontaneous lateralized circling behavior, impaired cognitive function, and epilepsy. Exploration-dependent induction of the immediate early gene Arc (activity-regulated cytoskeleton associated protein) in hippocampal neurons was examined in the general population of neurons versus neurons that were generated approximately 1 week after the ischemic insult and labeled with bromodeoxyuridine. Although Arc was inducible in a network-specific manner after severe neonatal stroke, it was impaired, not only in the ipsilateral injured but also in the contralateral uninjured hippocampi when examined 6 months after the neonatal stroke. Severity of both the stroke injury and the acquired poststroke epilepsy negatively correlated with Arc induction and new neuron integration into functional circuits in the injured hippocampi.

MRI with diffusion-weighted imaging in children and young adults with simultaneous supra- and infratentorial manifestations of Sturge-Weber syndrome.

BACKGROUND AND PURPOSE: Patients with Sturge-Weber syndrome (SWS) may present with neurological symptoms or neurocognitive deficits that cannot always be explained by the supratentorial findings seen on conventional MRI. Purpose of our study was to determine (a) what percentage of children with SWS have simultaneous supra- and infratentorial involvement and (b) what kind of infratentorial lesions are seen. In addition, we used DWI data to measure the ADC-values of normal appearing white matter (NAWM) to rule out impaired or delayed white matter maturation. MATERIAL AND METHODS: Fifteen SWS patients who underwent MRI/DWI between January 2000 and August 2008 were studied. Images were retrospectively reviewed by two experienced pediatric neuroradiologists. ADC measurements of the NAWM were performed at multiple locations within the brain. ADC-values were compared with normative data and with 18 matched normal controls from our hospital. RESULTS: Infratentorial involvement was seen in six out of 15 patients (40%). Cerebellar lesions included leptomeningeal enhancement, atrophy and developmental venous anomaly. ADC-values were increased in the NAWM of the frontal, parietal and occipital lobes of both hemispheres and in the pons. The ADC-values of the cerebellar white matter were increased in six out of eight affected cerebellar lobes. CONCLUSION: Infratentorial involvement of SWS is more frequently than previously thought. ADC analysis of the NAWM reveals impaired/altered white matter maturation distant from the area of leptomeningeal angiomatosis. This may explain neurocognitive deficits. ADC analysis of the NAWM may serve as biomarker of tissue injury and therefore guide treatment options.

Poststroke subgranular and rostral subventricular zone proliferation in a mouse model of neonatal stroke.

Stroke in the neonatal brain is an understudied cause of neurologic morbidity. Recently we have characterized a new immature mouse model of stroke utilizing unilateral carotid ligation alone to produce infarcts and acute seizures in postnatal day 12 (P12) CD-1 mice. In this study, the amount of poststroke neural progenitor proliferation was examined in the subgranular (SGZ) of the dentate gyrus and the subventricular zone (SVZ) 7, 14, and 21days after ischemia (DAI). A single IP injection (50 mg/kg) of bromodeoxyuridine (BrdU) given 2 hr before perfusion fixation labeled newborn cells. Early cell phenotypes were quantified by colabeling with GFAP, nestin, and DCX. Control mice revealed an age-dependent decrease in neural proliferation, with an approximately 50% drop in BrdU-labeled cell counts at P33 compared with P19 both in the SGZ and in the SVZ. Significant reduction in the amount of neural proliferation in the ipsilateral injured SGZ of ligated mice correlated with both the severity of the stroke-injury and the acute seizure scores. Similar correlations were not detected contralaterally. Contralateral SGZ neural proliferation was initially lowered at 7 DAI but normalized by 21 DAI. In both injured and control brains, approximately 90% of newborn SGZ cells colabeled with nestin, approximately 30% colabeled with GFAP, and a few colabeled with DCX. In contrast, poststroke SVZ cell proliferation was enhanced ipsi- more than contralaterally at 7 DAI. In the SVZ, the enhanced neural proliferation normalized to control levels by P33. In conclusion, the neural cell proliferation was differentially altered in the SGZ vs. SVZ after neonatal stroke.

Sturge-Weber syndrome with cerebellar involvement.

Sturge-Weber syndrome is a rare neurocutaneous disorder that typically presents with angiomas involving the face, ocular choroid and ipsilateral supratentorial leptomeninges. Posterior fossa involvement is extremely rare. We present two patients with simultaneous supra- and infratentorial involvement. Magnetic resonance imaging (MRI) and digital subtracted angiography (DSA) findings are discussed.

Neurogenesis and neuronal commitment following ischemia in a new mouse model for neonatal stroke.

Stroke in the neonatal brain is an important cause of neurologic morbidity. To characterize the dynamics of neural progenitor cell proliferation and maturation after survival delays in the neonatal brain following ischemia, we utilized unilateral carotid ligation alone to produce infarcts in postnatal day 12 CD1 mice. We investigated the neurogenesis derived from the sub-ventricular zone and the sub-granular zone of the dentate gyrus subsequent to injury. Newly produced cells were labeled by bromodeoxyuridine at approximately 1 week (P18-20) after the insult by 5 i.p. injections (each 50 mg/kg). Subsequent migration and differentiation of the newborn cells was investigated at postnatal day 40 by immunohistochemistry for molecular neuronal and glial cell-lineage markers and BrdU incorporation. Cresyl violet stain demonstrated massive loss of neurons in the ipsilateral septal hippocampus in the CA3 and CA1 regions associated with atrophy. Total counts of new cells were significantly lowered not only in the ipsilateral injured but also the contralateral uninjured hippocampi and correlated with the lesion induced atrophy. Bilateral percent neuronal commitments in the dentate gyri however, were not significantly different from control. New cell densities in the neocortex and striatum increased bilaterally after neonatal stroke. The predominantly non-neuronal commitment of the SVZ-derived new cells was similar to the percentage of non-neuronal commitment in controls. In conclusion, neurogenesis occurring at 1 week after neonatal ischemia in the model maintained cell-lineage commitment patterns similar to sham controls. However, the total number of hippocampal SGZ-derived new neurons was reduced bilaterally; in contrast, the SVZ-derived neurogenesis was amplified.

Novel clinical and serological aspects in non-allergic asthma.

BACKGROUND: We have recently observed that skin reactivity to autologous serum injection is common in patients with non-allergic asthma. However, clinical significance of skin reactivity to autologous serum remains to be defined. OBJECTIVE: To evaluate the possible relation between skin reactivity to autologous serum and clinical and laboratory characteristics in a series of patients with non-allergic asthma. METHODS: Fifty-five patients with non-allergic asthma underwent in vivo autologous serum skin test (ASST) and in vitro basophil histamine release assay using basophils from a normal donor. Clinical and laboratory characteristics including peripheral blood eosinophilia, antinuclear antibodies and total IgE concentration were evaluated. As control, ASST was performed in 10 allergic asthmatic patients, 10 patients with allergic rhinitis and 10 normal subjects. RESULTS: ASST was positive in 29/55 non-allergic asthmatics (53%), whereas it was negative in all 30 control subjects (P<0.001). The sera of 6 out of 51 patients induced in vitro histamine release from autologous basophils. The sera from two patients induced histamine release from membrane IgE-stripped basophils. A significant predominance of female sex (83%) and a high incidence of antinuclear antibodies (ANA) positivity (55%) were found among ASST-positive patients. CONCLUSION: These findings indicate that ASST is positive in about half patients with non-allergic asthma and that a proportion of patients (16%) has functional evidence of circulating histamine-releasing factors. In addition, predominance of female sex and frequent ANA positivity are in line with an autoimmune basis of non-allergic asthma.

Growth hormone deficiency in Sturge-Weber syndrome.

Sturge-Weber syndrome (SWS) is a disorder involving central nervous system abnormalities that may increase the risk of hypothalamic-pituitary dysfunction. Records of 19 patients with suspected growth hormone deficiency (GHD), identified from a registry of 1653 patients with SWS, were reviewed; nine patients with GHD were found.

Oromaxillofacial osseous abnormality in Sturge-Weber syndrome: case report and review of the literature.

We report a case of a 17-month-old child affected by Sturge-Weber syndrome who had unusually rapid overgrowth of the left frontal, temporal, orbital, and maxillary regions. CT angiography illustrated osteohypertrophy with periostitis and associated soft tissue hypertrophy directly corresponding to the distribution of the cutaneous port-wine stain. Extended maxillectomy was performed because of rapid growth and clinical debilitation, with surgical pathology revealing juvenile ossifying fibroma.

Autologous serum skin test reactivity in patients with non-allergic asthma.

BACKGROUND: Inflammatory alterations of respiratory airways have been found in patients with non-allergic asthma, but the triggering event has not been defined. An autoimmune activation of inflammatory cells has been hypothesized. OBJECTIVE: To evaluate whether histamine-releasing factors are present in sera from non-allergic asthmatics. METHODS: Twenty-four patients with non-allergic asthma underwent in vivo autologous serum skin test (ASST) and in vitro basophil histamine release assay using autologous basophils as well as basophils from normal donors. Twenty-seven subjects with respiratory allergy and three normal subjects were chosen as control. RESULTS: ASST was positive in 14/24 non-allergic asthmatics (58%) whereas it was negative in all 30 control subjects (P<0.001). The serum of only one ASST-positive patient out of 12 (8.4%) induced in vitro histamine release from autologous basophils. The serum from another ASST-positive patient induced histamine release from membrane IgE-stripped autologous basophils. Sera from either non-allergic asthmatics or from control subjects did not provoke significant histamine release from basophils from three normal donors. CONCLUSION: Skin reactivity to autologous serum is common among non-allergic asthmatics, indicating the presence of circulating histamine-releasing factors. However, only in a minority of patients in vitro functional evidence of histamine-releasing autoantibodies (anti-FcepsilonRI or anti-IgE) was obtained. The presence of circulating histamine-releasing factors might contribute to initiation/maintenance of inflammation in respiratory airways of non-allergic asthmatics.

Acute hemorrhagic complication of diagnostic lumbar puncture.

OBJECTIVE: To present a case of an epidural hematoma after lumbar puncture in a pediatric patient without known risk factors for such a complication and to review the literature regarding this complication. DESIGN: Case report, review of the literature, and discussion. DATA SOURCES: A review of MEDLINE (1966-1998) for keywords "lumbar puncture" and "hemorrhage" or "hematoma" was conducted, and each bibliography was reviewed for other sources extending to 1911. Articles describing a case of spinal hematoma after a lumbar puncture for any procedure were included. RESULTS: A 5-year-old boy underwent a lumbar puncture for evaluation of lethargy and fever, and subsequently developed marked back pain and severe pain on flexion of his legs. Magnetic resonance imaging revealed an epidural blood collection. The patient's symptoms resolved over the next few days in association with steroid administration. Multiple reports of epidural and subdural hematomas were found on literature review, most occurring in the setting of coagulation abnormalities. These reports involve lumbar puncture in anesthetic, interventional, and diagnostic settings. CONCLUSION: Lumbar puncture is a frequently employed procedure. Known complications include epidural, subdural, and subarachnoid hemorrhage, usually in the setting of abnormal coagulation. The case presented is unusual in that the patient is a child and lacks any known risk factors for a hemorrhagic complication. Such a complication appears to be rare; only five of the 64 cases discovered in the literature review occurred following this diagnostic procedure in patients without known risk factors.

Macrocryosectioning of the prostate: a simple technique.

Whole mount sections of the prostate are widely used in many laboratories. Macrocryosections of the gland; that is, whole mount frozen sections of the prostate from radical prostatectomies represent a useful new research protocol. The technique is very simple and does not require expensive equipment.

Familial clustering of autoimmune disorders and evaluation of medical risk factors in autism.

Autism is an age-dependent neurologic disorder that is often associated with autoimmune disorders in the patients' relatives. To evaluate the frequency of autoimmune disorders, as well as various prenatal and postnatal events in autism, we surveyed the families of 61 autistic patients and 46 healthy controls using questionnaires. The mean number of autoimmune disorders was greater in families with autism; 46% had two or more members with autoimmune disorders. As the number of family members with autoimmune disorders increased from one to three, the risk of autism was greater, with an odds ratio that increased from 1.9 to 5.5, respectively. In mothers and first-degree relatives of autistic children, there were more autoimmune disorders (16% and 21%) as compared to controls (2% and 4%), with odds ratios of 8.8 and 6.0, respectively. The most common autoimmune disorders in both groups were type 1 diabetes, adult rheumatoid arthritis, hypothyroidism, and systemic lupus erythematosus. Forty-six percent of the autism group reported having relatives with rheumatoid diseases, as compared to 26% of the controls. Prenatal maternal urinary tract, upper respiratory, and vaginal infections; asphyxia; prematurity, and seizures were more common in the autistic group, although the differences were not significant. Thirty-nine percent of the controls, but only 11% of the autistic, group, reported allergies. An increased number of autoimmune disorders suggests that in some families with autism, immune dysfunction could interact with various environmental factors to play a role in autism pathogenesis.

Clinical and neuroradiologic findings in infants with intracranial ependymomas. Pediatric Oncology Group.

Typical clinical characteristics, neuroradiologic findings, and initial neuroradiologic studies were reviewed for 40 patients <3 years of age with intracranial ependymomas, who were treated in the Pediatric Oncology Group (prolonged postoperative chemotherapy and delayed radiation for children <3 years of age with malignant brain tumors). The study included 16 females and 24 males, aged 3 to 35 months, who were diagnosed and registered in the study between 1986 and 1990. Commonly, patients presented with vomiting (70%), ataxia (53%), headache (28%), lethargy (28%), increased head circumference (23%), and irritability (23%). Duration of symptoms before diagnosis ranged from 1 day to 11 months. Thirty-five tumors (88%) were infratentorial; average tumor size was 4.3 (+/-1.4) x 4.2 (+/-1.7) x 4.1 (+/-1.8) cm at presentation. Noncontrast CT scans were performed on 23 patients; 13 (57%) were isodense to surrounding brain tissue and 13 (57%) were calcified. Contrast CT scans of 29 patients revealed that 28 (97%) were enhanced. Of the 15 T1-weighted MRI scans, 10 (67%) demonstrated low-signal intensity tumors, and 15 (94%) of the 16 T2-weighted scans revealed high-signal tumors. Forty-three percent of the tumors were cystic. Blood was observed within only 2 tumors and peritumoral edema was uncommon. Twenty-five percent of the ependymomas extended out to involve the dura, and 97% of the infratentorial tumors showed characteristic plasticity. Hydrocephalus was present in 34 (85%) children.

Identification of an apo-superoxide dismutase (Cu,Zn) pool in human lymphoblasts.

Copper incorporation (64Cu(II)) into Cu,Zn-superoxide dismutase (SOD) was studied in human lymphoblasts. Rapid incorporation of copper with a proportionate increase in SOD activity was detected. No copper incorporation or SOD activation was detected when 64Cu(II) was added to cell cytosols rather than to intact cells. Thus, incorporation of 64Cu was not due to isotopic exchange. Cycloheximide had no significant effect on copper incorporation and activation of SOD when the data were corrected for total cell copper. Thus, the data were consistent with copper incorporation into a preexisting apoSOD pool rather than newly synthesized SOD, and no new SOD synthesis was detected over a 15-h incubation period. The size of the apoSOD pool was estimated to be approximately 35% of the total SOD in lymphoblasts. When cells were preincubated for 15 h with excess copper (15 microM Cu(II)), the size of the apo pool markedly decreased but was not eliminated, suggesting that the apoSOD was not due to copper deficiency. These experiments also indicated that newly arrived copper was preferentially incorporated into the apoSOD pool, while the function(s) of an apoSOD pool remains unknown. Copper binding to apoSOD may provide a rapid protective response against copper toxicity.

Copper incorporation into superoxide dismutase in Menkes lymphoblasts.

The incorporation of copper into Cu,Zn-superoxide dismutase (SOD) was examined in Menkes lymphoblasts that express a genetic defect of copper metabolism. SOD activity was approximately 40% higher in Menkes than normal lymphoblasts. Since Menkes lymphoblasts contain elevated copper levels, the higher SOD activity is most likely due to near copper saturation of an apoSOD pool that is in normal lymphoblasts. Cycloheximide markedly inhibited 64Cu(II) incorporation into SOD in Menkes lymphoblasts under conditions in which no significant, de novo synthesis of SOD protein was detected with normal lymphoblasts. The maximal amount of 64Cu incorporation into newly synthesized SOD in Menkes lymphoblasts was approximately equal to the maximal amount of 64Cu that could be incorporated into the apoSOD pool in normal lymphoblasts. The increased synthesis of SOD in Menkes lymphoblasts may play a protective role against copper toxicity in Menkes lymphoblasts. The protonophore, CCCP markedly inhibited 64Cu incorporation into SOD in both normal and Menkes lymphoblasts, which is consistent with 64Cu incorporation into SOD within a membrane-bounded compartment in both cell types. When 64Cu-incorporation into SOD was blocked with CCCP, copper accumulated in a Superose column fraction that contains S-adenosylhomocysteine hydrolase (SAHH), which has a high affinity for copper. SAHH may play a role in delivering copper to SOD.

C-myc and tumour suppressor gene product expression in developing and term human trophoblast.

Proliferation and differentiation of villous trophoblast during placental development, from an early stage to full-term, were investigated in routinely fixed and processed tissues, by means of the immunocytochemical localization of the cell cycle-related proto-oncogene c-myc and the p53 and retinoblastoma susceptibility (Rb) tumour-suppressor gene products. The proliferative activity of the trophoblast was determined using an antibody against proliferating cell nuclear antigen (PCNA) which stains all proliferating cells in paraffin-embedded tissues. Diffuse nuclear immunoreactivity for PCNA, c-myc and Rb gene products was a consistent finding in early cytotrophoblast; c-myc product expression was also detectable in both layers of mid-gestation trophoblast. Only scattered cytotrophoblastic nuclei of early gestational placenta displayed immunostaining for p53 gene product. In full-term placenta c-myc expression was undetectable while Rb gene product and PCNA immunoreactivity declined markedly. These results indicate that the expression of the above genes is spatio-temporally regulated during placental development. A potential involvement of the oncosuppressor gene products p53 and Rb in the control of trophoblastic proliferation and of c-myc in the control of both the proliferative and differentiation pathways of trophoblastic cells is suggested.

The actin cytoskeleton mediates the hormonally regulated translocation of type II iodothyronine 5'-deiodinase in astrocytes.

Thyroid hormone, specifically thyroxine, alters cytoskeletal organization in astrocytes by modulating actin polymerization and, in turn, regulates the turnover of the short-lived membrane protein, type II iodothyronine 5'-deiodinase. In the absence of thyroxine, approximately 35% of the total cellular actin is depolymerized, and greater than 90% of the deiodinase is found in the plasma membrane and not associated with the cytoskeleton. Addition of thyroxine promotes actin polymerization and decreases the depolymerized actin to approximately 10% of the total actin pool, induces binding of the deiodinase to F-actin, and promotes rapid internalization of the enzyme. These data provide direct evidence that the actin cytoskeleton participates in the inactivation pathway of the deiodinase by translocating this short-lived plasma membrane protein to an internal membrane pool.