The syndrome of systemic carnitine deficiency. Clinical, morphologic, biochemical, and pathophysiologic features

An 11-year old boy had had recurrent episodes of hepatic and cerebral dysfunction and underdeveloped musculature. Overt weakness developed at age 10. Lipid excess, especially in type I fibers, was found in muscle. Hypertrophied smooth endoplasmic reticulum and excessive microbodies were present in liver. Marked carnitine deficiency was shown in skeletal muscle, plasma, and liver. Ketogenesis was impaired on a high fat diet, but omega oxidation of fatty acids was enhanced. There was excessive glucose uptake and essentially no oxidation of labeled long-chain fatty acids by perfused forearm muscles in vivo. Oral replacement therapy restored plasma carnitine levels to normal, but not liver or muscle carnitine levels, and was accompanied by clinical improvement.

Metabolic dysfunction in Alzheimer's disease and related neurodegenerative disorders

Alzheimer's disease and other related neurodegenerative diseases are highly debilitating disorders that affect millions of people worldwide. Efforts towards developing effective treatments for these disorders have shown limited efficacy at best, with no true cure to this day being present. Recent work, both clinical and experimental, indicates that many neurodegenerative disorders often display a coexisting metabolic dysfunction which may exacerbate neurological symptoms. It stands to reason therefore that metabolic pathways may themselves contain promising therapeutic targets for major neurodegenerative diseases. In this review, we provide an overview of some of the most recent evidence for metabolic dysregulation in Alzheimer's disease, Huntington's disease, and Parkinson's disease, and discuss several potential mechanisms that may underlie the potential relationships between metabolic dysfunction and etiology of nervous system degeneration. We also highlight some prominent signaling pathways involved in the link between peripheral metabolism and the central nervous system that are potential targets for future therapies, and we will review some of the clinical progress in this field. It is likely that in the near future, therapeutics with combinatorial neuroprotective and 'eumetabolic' activities may possess superior efficacies compared to less pluripotent remedies.

The childhood type of dermatomyositis

The childhood type fo dermatomyositis, which occurs in children and young adults, shows a specific constellation of pathologic changes in muscle. Capillary necrosis leads to capillary loss, generally starting on the periphery of muscle fascicles. Electron microscopy discloses undulating tubules in endothelial cells, lymphocytes, pericytes, and pseudosatellite cells. The muscle fiber damage is coextensive with capillary damage and probably results from progressive ischemia. The muscle cells, before atrophying, show mitochondrial elongation, Z disk streaming, focal myofibrillary loss, and occassionally selective thick filament loss. Muscle cell necrosis is rare and limited to infarctlike lesions. Inflammatory infiltrates, if present, occur only in connective tissue septa. The cause of the capillary damage has not been determined.

X-ray holograms at improved resolution: a study of zymogen granules

X-ray holography offers the possibility of three-dimensional microscopy with resolution higher than that of the light microscope and with contrast based on x-ray edges. In principle, the method is especially advantageous for biological samples if x-rays in the wavelength region between the carbon and oxygen K edges are used. However, until now the achieved resolution has not exceeded that of the light microscope because of the poor coherence properties of the x-ray sources and the low resolution of the detectors that were available. With a recently developed x-ray source based on an undulator on an electron storage ring, and high resolution x-ray resist, a hologram has been recorded at about 400-angstrom resolution. The experiment utilized x-rays with wavelengths of 24.7 angstroms and required a 1-hour exposure of the pancreatic zymogen granules under study.

Cytochrome c oxidase-associated Leigh syndrome: phenotypic features and pathogenetic speculations

Fourteen new cases of cytochrome oxidase (COX)-associated Leigh syndrome (LS) are combined with 20 reported cases to describe the clinical, laboratory, and radiological features of this devastating metabolic condition. Three clinical stages are identified. Most patients have normal neurological development during the first 8-12 months (stage I). Somatic complaints are common, including chronic diarrhea, recurrent vomiting, anorexia, and decelerating body and head growth. The second stage evolves during late infancy and early childhood when motor regression becomes evident. Eye signs, altered breathing patterns, pyramidal, extrapyramidal, and cerebellar signs emerge and sudden clinical deterioration occurs during intercurrent infectious or metabolic stress. The last stage may extend from 2 to 10 years and is manifested by extreme hypotonia, swallowing difficulties and undernutrition. Feeding assistance is necessary and seizures may occur. The CSF lactate concentration is consistently elevated and MRI abnormalities are seen in the subcortical structures. COX deficiency affects most tissues, but is not always generalized. For example, 3 patients with a cardiomyopathy had normal COX activity in cultured skin fibroblasts. Nearly normal amounts of cross-reacting material are present by ELISA and immunoblot analyses. Parental consanguinity has been found in several families, the hereditary pattern is recessive and males are affected more commonly (2:1). The biomolecular abnormality causing COX deficiency in LS is unknown, but the available evidence implicates a nuclear-encoded protein that affects the structure or the stability of the holoenzyme complex.

Attention deficit disorder: quantitative analysis of CT

We compared the measurements of CTs in two groups of children: 35 satisfying DSM III criteria for attention deficit disorder (ADD) and 27 controls with other conditions. The groups were comparable in age, sex, and IQ. Measurements of the anterior horns of the lateral ventricles, bifrontal width, and right and left hemispheres did not differ. The ratio of ventricular size/bifrontal brain width (Evan's Index) averaged 0.237 in ADD and 0.263 in controls--results similar to those obtained in normal children by other investigators. Our findings suggest that when quantitative techniques, contrast populations, and "blind" analysis of CTs are employed, the results are indistinguishable in children with ADD and contrasts. If anatomic abnormalities are present in ADD, they are not discernible with current CT technology.

Pathological involvement of primary sensory neurons in Werdnig-Hoffmann disease

Seven patients with the typical clinical picture and muscle biopsy findings of classical Werdnig-Hoffmann disease showed Wallerian degeneration in their biopsied sural nerves. In dorsal root ganglia of one patient there were residual nodules and several chromatolytic neurons. By electron microscopy the changes of chromatolysis were confirmed and found to be consistent with an axonal reaction. Involvement of the primary sensory neuron is probably a regular pathologic feature of Werdnig-Hoffmann disease. The type of abnormality suggests in initial failure of the axon distal to the nerve roots.

A scanning electron microscope study of the in vitro development of dissociated hippocampal cells

Cultures of dissociated hippocampal neurons from 18-day-old rat fetuses were examined by scanning electron microscopy after periods between one hour and 20 days following plating on a poly-L-lysine coated substrate. Cell attachment was virtually complete within one hour after plating, and at that stage many cells could be seen which had started to extend processes with broad growth cones. By four hours in culture, process formation was well advanced and some cells had already assumed a pyramidal configuration. After 16 hours in culture, numerous contacts were seen between neighboring growth cones, and this frequently led to fasciculation of the interacting fibers. During the next three weeks the cell bodies enlarged considerably and rounded-up, and two distinct types of processes became evident: large, rapidly tapering dendrite-like processes and finer, essentially uniform-diametered processes that resemble axons. In most of the older cultures a dense plexus of processes was formed, and many of the finer processes appeared to have "bouton-like" swellings as they traversed the upper surfaces of the neuronal perikarya. Non-neuronal elements, which comprised only about 5% of the cells initially plated, rapidly proliferated in our cultures and within three to six days formed a confluent monolayer beneath the neurons.

Early diagnosis of cerebral X-linked adrenoleukodystrophy in boys with Addison's disease improves survival and neurological outcomes

Approximately one third of boys with X-linked adrenoleukodystophy (X-ALD) develop an acute, progressive inflammatory process of the central nervous system, resulting in rapid neurologic deterioration and death. Hematopoietic cell transplantation (HCT) can halt the progression of neurologic disease if performed early in the course of the cerebral form of X-ALD. We describe a retrospective cohort study of 90 boys with X-ALD evaluated at our institution between 2000 and 2009, to determine if early diagnosis of X-ALD following the diagnosis of unexplained adrenal insufficiency (AI) improves outcomes. We describe seven cases with a delay in the diagnosis of X-ALD and compare their outcomes to ten controls with the diagnosis of ALD made within 12 months following diagnosis of AI. At the time of evaluation for HCT, boys with a delay in the diagnosis of X-ALD had more extensive cerebral involvement and more limited functioning. These boys also were 3.9 times more likely to die and had significant advancement of cerebral disease after HCT, compared with boys with a timely diagnosis of X-ALD. In conclusion, the early diagnosis of cerebral X-ALD following the diagnosis of unexplained AI, and subsequent treatment with HCT improves both neurological outcomes and survival in boys with cerebral X-ALD.

Femtosecond diffraction studies of solid and liquid phase changes in shock-compressed bismuth

Bismuth has long been a prototypical system for investigating phase transformations and melting at high pressure. Despite decades of experimental study, however, the lattice-level response of Bi to rapid (shock) compression and the relationship between structures occurring dynamically and those observed during slow (static) compression, are still not clearly understood. We have determined the structural response of shock-compressed Bi to 68 GPa using femtosecond X-ray diffraction, thereby revealing the phase transition sequence and equation-of-state in unprecedented detail for the first time. We show that shocked-Bi exhibits a marked departure from equilibrium behavior - the incommensurate Bi-III phase is not observed, but rather a new metastable phase, and the Bi-V phase is formed at significantly lower pressures compared to static compression studies. We also directly measure structural changes in a shocked liquid for the first time. These observations reveal new behaviour in the solid and liquid phases of a shocked material and give important insights into the validity of comparing static and dynamic datasets.

Ultrafast X-Ray Diffraction Studies of the Phase Transitions and Equation of State of Scandium Shock Compressed to 82 GPa

Using x-ray diffraction at the Linac Coherent Light Source x-ray free-electron laser, we have determined simultaneously and self-consistently the phase transitions and equation of state (EOS) of the lightest transition metal, scandium, under shock compression. On compression scandium undergoes a structural phase transition between 32 and 35 GPa to the same bcc structure seen at high temperatures at ambient pressures, and then a further transition at 46 GPa to the incommensurate host-guest polymorph found above 21 GPa in static compression at room temperature. Shock melting of the host-guest phase is observed between 53 and 72 GPa with the disappearance of Bragg scattering and the growth of a broad asymmetric diffraction peak from the high-density liquid.

The endocrine secretion of mammalian digestive enzymes by exocrine glands

The exocrine pancreas and certain salivary glands of mammals secrete a variety of enzymes into the gastrointestinal tract, where they digest food. The same glands also release these enzymes into the bloodstream. This latter process has commonly been assumed to occur solely as the result of a pathological condition or as an inadvertent by-product of exocrine secretion due to the leakage of trace quantities of the enzymes into blood. However, a variety of evidence suggests that the endocrine secretion of digestive enzymes is a normal occurrence that can be of substantial magnitude in healthy individuals, is responsive to various physiological stimuli, and is distinct from exocrine secretion. Recent research has focused attention on this process as a promising means for the delivery of engineered proteins into the systemic circulation for pharmaceutical purposes. In this review, we survey research in this area and consider the evidence for the existence of an endocrine secretion of digestive enzymes, the cause of enzyme release into the bloodstream, its source within the tissue, and, finally, the physiological purposes that this secretion process might serve.

Lumbar facet fracture as a possible source of pain after lumbar laminectomy

This study compared 50 patients with lumbar facet fractures and continued pain after lumbar laminectomy with a postlaminectomy control group without facet fractures. Computed tomographic analysis compared variables including direct measurements of bone resection. Average follow-up between surgery and postsurgical computed tomographic examination was 3.2 years. In the fracture group, more than one half of the bone immediately above the flare of the inferior articular process at the level of the laminectomy, measured in a medial to lateral direction, had been resected. No one in the control group had more than one quarter of this bone removed (P = .0001). Lumbar facet fractures may be one cause of late postlaminectomy pain. Caution in resection of a particular area of bone may avoid this problem.

Identification of a new strain of fastidious enterovirus 70 as the causative agent of an outbreak of hemorrhagic conjunctivitis

A 1994 outbreak of acute hemorrhagic conjunctivitis in Israel was caused by an enterovirus 70 strain that was distinct from previously reported strains. Characterization was by electron microscopy (eye washes), reverse transcription-PCR (RT-PCR; eyewash, specimens, eye swabs, and tears), and sequence analysis of RT-PCR-amplified fragments from the 5' noncoding region and VP1.

Mechanism of Spontaneous Cure in Puberty of Ringworm of the Scalp

With onset of puberty, the sebaceous glands of the scalp start to secrete a sebum which contains, in higher concentration than before, lowboiling saturated fatty acids with selective fungistatic and fungicidal action on M. audouini. Highly active normal aliphatic monobasic acids having odd numbers of carbon atoms, including pelargonic acid, have been isolated from hair fat of adults. The "adult type" of hair fat does not kill the fungus spores within the hair but prevents infection of the new hair following the old infected hair in the process of shedding. Detailed reports are to be published elsewhere.

DNA immunization with HBsAg-based particles expressing a B cell epitope of amyloid β-peptide attenuates disease progression and prolongs survival in a mouse model of Alzheimer's disease

Alzheimer's disease (AD) is an incurable and progressive neurodegenerative senile disorder associated with the brain accumulation of Aβ plaques. Although vaccines that reduce Aβ plaques can control AD, the rationale for their use at the onset of the disease remains debatable. Old humans and mice usually respond poorly to vaccines due to presumably age-related immunological impairments. Here, we report that by modifying vaccines, the poor responsiveness of old mice can be reversed. Unlike the Aβ peptide vaccine, DNA immunizations with the amino-terminal Aβ(1-11) fragment exposed on the surface of HBsAg particles elicit high levels of anti-Aβ antibody both in young and old mice. Importantly, in AD model 3xTgAD mice, the vaccine reduced Aβ plaques, ameliorated cognitive impairments and, surprisingly, significantly increased life span. Hence, we propose that vaccines targeting Aβ(1-11) can efficiently combat AD-induced pathological alterations and provide survival benefit in patients with AD.

Nonparallel transport and mechanisms of secretion

After many years of controversy, it is now clear that at least some cells and tissues that secrete more than one product can vary the composition of the secreted mixture as the result of the differential transport of various substances out of the cells that secrete them. In this article we discuss this phenomenon, non-parallel transport or secretion, and how it has and continues to inform us about how cells release the products they manufacture. We focus on expression of the phenomenon in the secretion of digestive enzymes by the exocrine pancreas, where it has been studied most extensively.

Unilateral cryptophthalmia

Two patients had the variable clinical features of unilateral cryptophthalmia. A 5-month-old boy had isolated unilateral cryptophthalmia: a small boney orbit, deformed optic canal, and a small amorphous mass with no normal intraocular tissue representing the globe. No extraocular muscles or optic nerve were identified by B-scan ultrasound or by computed axial tomography x-ray techniques. The second patient, a 13-year-old girl, had unilateral cryptophthalmia, and numerous systemic abnormalities including a head circumference less than the third percentile, severe mental retardation, hypoplasia of the left side of the head, and a left facial cleft deformity. She also had contractures of hips, knees and ankles, and bilateral spasticity and jerky movements. The left boney orbit was contracted and deformed and contained a small amorphous tissue with no ocular detail, as revealed by B-scan and computed tomography scan.