Factors determining the risk of the metabolic syndrome: is there a central role for adiponectin?

BACKGROUND AND OBJECTIVES

The pathogenesis of the metabolic syndrome (MetS) is not well understood. This review is based on the hypothesis that both traditional and emerging risk factors act through adiponectin.

SUBJECTS AND METHODS

We conducted a search of the literature using prominent electronic databases and search terms that included in combination: adiponectin, diet, dietary patterns, exercise, metabolic rate, MetS and testosterone. Articles were restricted to studies conducted on adult humans, reported in English and within the time period 2000-2012.

RESULTS AND CONCLUSIONS

Both traditional and emerging risk factors associated with the MetS show some evidence of exerting their influence through adiponectin. High-quality randomized controlled trials that alter adiponectin levels are required to further corroborate this hypothesis.

Repeated anterior chamber fluorophotometric evaluation of the eyes of ophthalmologically normal dogs

OBJECTIVE

To perform repeated anterior chamber fluorophotometry on both eyes of ophthalmologically normal dogs to measure fluorescein concentrations over a 5-day period and identify any change in the degree of anterior chamber fluorescence over time or difference between eyes.

ANIMALS

9 healthy adult dogs (18 eyes).

PROCEDURES

Each dog received an IV injection of 10% fluorescein solution, and anterior chamber fluorophotometry was performed 1 hour later on both eyes. This procedure was repeated at the same time each day for 5 consecutive days.

RESULTS

A significant increase in fluorescein concentration was evident in the anterior chamber on day 5 in the right eye and days 2, 3, 4, and 5 in the left eye. There was no significant difference in concentration between the left and the right eyes on any day.

CONCLUSIONS AND CLINICAL RELEVANCE

The increase in ocular fluorescein concentration in the study dogs was unlikely to be of clinical importance and is only pertinent for subsequent research studies. This is a limitation that should be considered when reporting fluorophotometry data as fluorescein concentration or as change in fluorescein concentration from baseline.

Neuroanatomy of holoprosencephaly as predictor of function: beyond the face predicting the brain

BACKGROUND

Despite advances in neuroimaging and molecular genetics of holoprosencephaly (HPE), the clinical spectrum of HPE has remained inadequately described.

OBJECTIVE

To better characterize the clinical features of HPE and identify specific neuroanatomic abnormalities that may be useful predictors of neurodevelopmental function.

METHODS

The authors evaluated 68 children with HPE in a multicenter, prospective study. Neuroimaging studies were assessed for the grade of HPE (lobar, semilobar, and alobar), the degree of nonseparation of the deep gray nuclei, and presence of dorsal cyst or cortical malformation.

RESULTS

In general, the severity of clinical problems and neurologic dysfunctions correlated with the degree of hemispheric nonseparation (grade of HPE). Nearly three-quarters of the patients had endocrinopathies, with all having at least diabetes insipidus. The severity of endocrine abnormalities correlated with the degree of hypothalamic nonseparation (p = 0.029). Seizures occurred in approximately half of the children with HPE. The presence of cortical malformations was associated with difficult-to-control seizures. The presence and degree of dystonia correlated with the degree of nonseparation of the caudate and lentiform nuclei and the grade of HPE (p < 0.05). Hypotonia correlated with the grade of HPE (p < 0.05). Mobility, upper extremity function, and language correlated with the degree of nonseparation of the caudate, lentiform and thalamic nuclei, and grade of HPE (p < 0.01).

CONCLUSIONS

Patients with HPE manifest a wide spectrum of clinical problems and neurologic dysfunction. The nature and severity of many of these problems can be predicted by specific neuroanatomic abnormalities found in HPE.

Effectiveness of N,N-dimethylglycine in autism and pervasive developmental disorder

N,N-dimethylglycine, a dietary supplement, has been reported to be beneficial in children with autism and pervasive developmental disorder. We examined the effectiveness of dimethylglycine in children with autism and pervasive developmental disorder in a double-blind, placebo-controlled study. Thirty-seven children between 3 and 11 years of age with a diagnosis of autism and/or pervasive developmental disorder were gender and age matched and randomly assigned to receive either placebo or dimethylglycine for 4 weeks. All children were assessed before and after treatment on two behavioral measures, the Vineland Maladaptive Behavior Domain and the Aberrant Behavior Checklist. Standardized neurologic examinations before and after treatment on 33 children showed no change. An overall improvement on all behavioral measures was observed for both the placebo and the dimethylglycine groups. However, the improvement among the children who received dimethylglycine was not statistically different from the improvement observed among the children who received the placebo. The children who participated in this study were a heterogeneous group, and their apparent responses to the dimethylglycine varied. Some children appeared to respond positively to the dimethylglycine, and there was a smaller proportion of negative changes in the dimethylglycine group, but the quantitative changes in the dimethylglycine behavioral assessments were not significantly different from what was observed among children who received placebo.

Assessment of the deep gray nuclei in holoprosencephaly

BACKGROUND AND PURPOSE

Although holoprosencephaly has been known for many years, few detailed analyses have been performed in a large series of patients to outline the range of morphology in this disorder, particularly regarding the deep gray nuclear structures. We reviewed a large patient cohort to elucidate the combinations of morphologic aberrations of the deep gray nuclei and to correlate those findings with recent discoveries in embryology and developmental neurogenetics.

METHODS

A retrospective review of the imaging records of 57 patients (43 MR studies and 14 high-quality CT studies) to categorize the spectrum of deep gray nuclear malformations. The hypothalami, caudate nuclei, lentiform nuclei, thalami, and mesencephalon were graded as to their degree of noncleavage. Spatial orientation was also evaluated, as was the relationship of the basal ganglia to the diencephalic structures and mesencephalon. The extent of noncleavage of the various nuclei was then assessed for statistical association.

RESULTS

In every study on which it could be accurately assessed, we found some degree of hypothalamic noncleavage. Noncleavage was also common in the caudate nuclei (96%), lentiform nuclei (85%), and thalami (67%). Complete and partial noncleavage were more common in the caudate nuclei than in the lentiform nuclei. The degree of thalamic noncleavage was uniformly less than that in the caudate and lentiform nuclei. Abnormalities in alignment of the long axis of the thalamus were seen in 71% of cases, and were associated with degree of thalamic noncleavage; 27% of patients had some degree of mesencephalic noncleavage.

CONCLUSION

The hypothalamus and caudate nuclei are the most severely affected structures in holoprosencephaly, and the mesencephalic structures are more commonly involved than previously thought in this "prosencephalic disorder." These findings suggest the lack of induction of the most rostral aspects of the embryonic floor plate as the cause of this disorder.

Hypertonia, hyperreflexia, and excessive startle response in a neonate

Following an uneventful gestation, a newborn girl presented with hypertonia, hyperreflexia, tremor, and excessive startle response. Nose tap elicited a dramatic head recoil. Her mother had similar symptoms beginning as a child that improved but persisted into adulthood. In addition, several members of mother's family died unexpectedly in infancy. Hypertonia in the newborn period indicates central nervous system dysfunction of several possible causes, most of which are associated with severe cognitive deficits and limited neurological development.

Folinic acid-responsive neonatal seizures

We report three cases of folinic acid-responsive intractable neonatal seizures. All patients were born at term following normal gestation and delivery. In the first infant, seizures began on the 5th day of life and were unresponsive to phenobarbital, pyridoxine, and valproate, but stopped within 24 hours of initiation of folinic acid treatment at the age of 6 months. Her sibling had died at age 6 months with intractable seizures. In the second infant, seizures began in the 2nd hour of life. These were initially controlled with phenobarbital; however, at 3 months of age she developed status epilepticus refractory to anticonvulsants, steroids, and pyridoxine and she required repeated induction of pentobarbital coma. Seizures stopped within 24 hours of starting folinic acid. Seizures and encephalopathy were noted in the third infant on the 2nd day of life. These were controlled with phenobarbital, but at 8 weeks of age seizures recurred and were difficult to control despite the addition of phenytoin. Immediately after folinic acid was initiated the seizures stopped. Breakthrough seizures in all patients have responded to increases in folinic acid; two of the three remain on standard anticonvulsants. All patients have global developmental delay. Cranial magnetic resonance imaging in the second patient shows diffuse atrophy, and in the third patient shows increased signal on T2 images in the white matter of the frontal and parietal lobes. Analysis of cerebrospinal fluid from these patients using high-performance liquid chromatography with electrochemical detection has consistently revealed an as-yet unidentified compound, which can be used as a marker for this condition. We suggest that cerebrospinal fluid be analyzed for the presence of this compound and a trial of folinic acid be considered in neonates with unexplained early onset intractable seizures.

Schizencephaly: correlations of clinical and radiologic features

Schizencephaly is an uncommon congenital disorder of cerebral cortical development. Although a well-recognized cause of seizures and developmental deficits in children, previous reports describe the range of neurodevelopmental outcome in only 47 patients. We report the clinical and cranial imaging features of 47 children with unilateral open-lip (17), unilateral closed-lip (12), bilateral open-lip (12), and bilateral closed-lip (6) schizencephaly, as defined radiologically. The schizencephalic cleft occurred more often in the anterior than in the posterior neocortex. Children with closed-lip schizencephaly presented with hemiparesis or motor delay whereas patients with open-lip schizencephaly presented with hydrocephalus or seizures. Forty-three patients (91%) had associated cerebral developmental anomalies, most commonly absence of the septum pellucidum (45%) and focal cortical dysplasia (40%). There was a history of seizures in 57% of cases, a third of which were classified as difficult to control. Neurodevelopmental outcome was generally poor, with 51% of patients (24/47) having severe deficits, 32% of patients (15/47) having moderate impairment, and 17% of patients (8/47) having mild or no problems. Patients with closed-lip schizencephaly were more likely to have a mild to moderate outcome than those with open-lip type (78% versus 31%; p < 0.05). Children with unilateral schizencephaly had a mild or moderate outcome more frequently than those with bilateral lesions (62% versus 28%; p < 0.05). Children who had involvement of a single lobe accounted for 88% of those with mild outcomes and 53% of those with moderate outcomes. Unilateral closed-lip schizencephaly was associated with the best neurodevelopmental outcome; in contrast, 11 of 12 children with bilateral open-lip clefts had severe disabilities. Language development was significantly more likely to be normal in those children with unilateral schizencephaly than in those with bilateral clefts (48% versus 6%; p < 0.002). Thus, the presentation and outcome of children with schizencephaly are quite variable but are related to the extent of cortex involved in the schizencephalic defect.

Neonatal hypotonia

The approach to a newborn with hypotonia should not differ substantially from that to an older patient. The examination may be more difficult to interpret, especially in evaluating mental status and muscle strength. However, laboratory studies such as serum enzymes, EMG, and muscle biopsy may be very specific in helping the neurologist to arrive at a diagnosis, even in premature infants.

Pharmacologic management of neonatal cerebral ischemia and hemorrhage: old and new directions

New developments in pharmacologic management of cerebral ischemia and hemorrhage are reviewed. A number of agents with diverse modes of action have now been shown to be neuroprotective in adult and neonatal animal models when administered either before or after a hypoxic-ischemic insult. As experience improves with these agents in hypoxic-ischemic injury and periventricular-intraventricular hemorrhage in human neonates, there is reason to be optimistic that effective neuroprotective strategies will soon be clinically available.

Demyelinating polyneuropathy in eosinophilia-myalgia syndrome

Eosinophilia-myalgia syndrome (EMS) is a newly recognized disorder, characterized by myalgia, weakness, scleroderma-like changes, and eosinophilia. EMS is associated with lots of L-tryptophan allegedly contaminated with byproducts of the manufacturing process. We describe 3 patients with EMS who presented with a severe demyelinating sensorimotor polyneuropathy. Electrodiagnostic studies revealed multifocal conduction block, slowing and temporal dispersion of motor responses, and prolonged or absent F-responses. Despite plasmapheresis; corticosteroids; and, in 1 patient, cyclophosphamide, 2 patients died and the remaining patient experienced minimal recovery. Pathology revealed patchy perivascular infiltrates and fibrosis in the connective tissue of muscle and nerve. Autopsy of the central nervous system in 2 patients did not reveal changes unique to EMS. In addition to other organ involvement, EMS may manifest as a potentially fatal polyneuropathy, which initially appears to have prominent demyelinating features.

Occupational exposures and brain cancer mortality: a preliminary study of east Texas residents

The relationship between various occupational exposures and brain cancer was investigated in a case-control study using mortality data from 202 males who died in East Texas from gliomas in 1969-1978 and 238 male controls randomly selected from all deaths in East Texas in 1969-1978. Using the occupational classification scheme of the U.S. Bureau of the Census, the risk for brain cancer was significantly increased for male workers employed in the transportation, communication, and utilities industries [odds ratio (OR) = 2.26, confidence intervals (CI) = 1.18-4.32]. Further examination of this finding showed that male workers employed in occupations associated with electricity or electromagnetic (EM) fields had an elevated risk for brain cancer (OR = 3.94, CI = 1.52-10.20). In addition, there was a linear relationship between the probability of exposure to EM fields and brain cancer. Significantly elevated risk for brain cancer was also found among male workers in the trucking industry.