Energy metabolism in free-living, 'large-eating' and 'small-eating' women: studies using 2H2(18)O

The doubly-labelled water (2H2(18)O) technique was used to assess the long-term rates of energy expenditure and, after accounting for any changes in body composition, the derived rates of energy intake in weight-stable 'large-eating' (n 6) and 'small-eating' (n 6) women. The self-reported energy intakes (approximately 11.2 v. 5.6 MJ/d) and energy expenditures (approximately 8.5 v. 12.4 MJ/d) for the 'large-eating' and 'small-eating' groups respectively, should not be sustainable without significant body-weight changes. 2H2(18)O-assessed rates of energy expenditure for the 'large-eaters' (approximately 8.5 MJ/d) and 'small-eaters' (approximately 11.3 MJ/d) were in close agreement with the results obtained using 5 d, self-reported activity diaries but the derived rates of energy intake for the 'large-' (approximately 8.5 MJ/d) and 'small-eaters' (approximately 10.8 MJ/d) were markedly different from those obtained using self-reported, weighed food diaries. When two 'small-eaters' were supplied with their self-reported energy intakes (approximately 5 MJ/d) for up to 28 d both subjects lost about 0.75 kg body-weight/week. These results provide no support for the existence of 'metabolically efficient' women in the community.

Ironic catastrophes: one's food--another's poison

Iron deficiency is an important nutritional problem in third world countries because it diminishes work performance. In meat-eating countries, iron excess may be more important than iron deficiency. Heme iron is more efficiently absorbed from the diet than inorganic iron, and iron excess can produce cellular oxidation in association with superoxide dismutase. Metal ion catalysis is linked to aging, coronary artery disease, stroke, carcinogenesis, neurodegenerative disorders, and inflammatory disorders. Prudence is advised in the excessive consumption of meat and iron supplementation of the diet until this process is more thoroughly investigated.

The calcitonin gene is expressed in salmon gills

Calcitonin is an important physiological regulator of salmon gills. Although the calcitonin receptor was found in salmon gills, the critical question concerning the source of the hormone remained unanswered. In this communication, evidence is presented for expression of calcitonin mRNA and its encoded peptide in gills of the pink salmon, Oncorhynchus gorbuscha. The expression of calcitonin gene transcripts was demonstrated by reverse transcription-polymerase chain reaction, Southern hybridization, and sequencing. The sequencing identified a sequence corresponding to that of exon 4 of the salmon calcitonin gene. Expression of the encoded calcitonin gene in gills was detected by radioimmunoassay in gill extracts. This synthesis of calcitonin in gills, which also possess specific receptors to the peptide, suggests function of an autocrine or paracrine process producing calcitonin in this tissue. These observations confirm and extend previous reports on the physiological role of calcitonin in fish gills.

Fibroblast growth factor in the hypothalamic-pituitary axis: differential expression of fibroblast growth factor-2 and a high affinity receptor

In situ hybridization and immunohistochemistry were used to map gene expression and protein distribution of basic fibroblast growth factor (FGF-2) in the hypothalamic-pituitary system. Although the expression of FGF-2 mRNA in the pituitary is low, the protein is widely distributed in both its neural and anterior lobes. In the anterior lobe, immunoreactive (ir-) FGF-2 localizes to basement membranes and select endocrine cells. In the neural lobe, ir-FGF-2 is detected in basement membranes, pituicytes, and Herring bodies. Analyses of FGF high affinity receptor (FGFR) immunoreactivity in the anterior pituitary establishes a distribution of FGFR similar to that of FGF-2. In the neural lobe, ir-FGFR is associated with nerve fibers, pituicytes, and Herring bodies. Unlike FGF-2, the distribution of FGFR1 mRNA correlates well with the presence of the immunoreactive receptor. In the hypothalamus, magnocellular neurons of paraventricular and supraoptic nuclei contain ir-FGF-2 and ir-FGFR. In the median eminence, ir-FGF-2 and ir-FGFR is associated with fibers, glial, and endothelial cells. Ependymal and subependymal cells lining the third ventricle also show high levels of ir-FGF-2 and ir-FGFR and mRNAs. Overall, there is a specific and selective distribution of FGF-2 and its high affinity receptor(s) in the hypothalamo-pituitary axis. This localization lead us to postulate a role in neurohypophyseal functions, possibly water balance.

Hepatic granulomas due to visceral larva migrans in adults: appearance on US and MRI

Visceral larva migrans is a syndrome characteristically involving children with a history of pica, and usually presents with fever, abdominal pain, tender hepatomegaly, and hypereosinophilia. Hepatic granulomas of visceral larva migrans are rare in adults. We describe three adult patients with hepatic lesions which on histopathology demonstrated characteristic granulomas of visceral larva migrans. All patients had abdominal sonograms and two had additional MR scans of the liver. Both ultrasound and magnetic resonance imaging demonstrated characteristic appearances which have not been described previously (viz., ill-defined central necrotic areas surrounded by concentric thick walls and perifocal edema in the liver parenchyma).

Lymphocytic hypophysitis. Case report

A case of lymphocytic hypophysitis is described in a patient presenting with panhypopituitarism 8 years after her last childbirth. The patient developed headache, vomiting, and diplopia (due to palsy of the right lateral rectus muscle) 7 months after delivery of her last baby. The diplopia disappeared after a few days with symptomatic treatment, and the headache and vomiting decreased in intensity with analgesic therapy. Eight years later the patient developed symptoms suggestive of hypoadrenalism, hypothyroidism, and amenorrhea. Investigations revealed panhypopituitarism with a pituitary mass lesion. Repeat evaluation 1 year later demonstrated no change in the size of the pituitary gland. The patient underwent transsphenoidal surgery with a provisional diagnosis of pituitary adenoma. Histological examination of the resected gland revealed evidence of lymphocytic hypophysitis. Symptoms suggestive of a pituitary mass lesion were noted during the peripartum period, but features of hypopituitarism developed much later. Such a long latent period has not been reported before. This report also highlights the fact that glandular enlargement may persist for many years after the onset of lymphocytic hypophysitis.

Confocal imaging of glial cells in the intact rat optic nerve

Astrocytes and oligodendrocytes in the isolated intact mature rat optic nerve have been computer imaged in three dimensions by laser scanning confocal microscopy of single cells, dye-filled with lysinated rhodamine dextran (LRD). Our results illustrate the first application of these techniques to an intact CNS white matter tract and provide comparative data for previous studies on neonatal rat optic nerve (Butt and Ransom: Glia 2:470-475, 1989; Butt and Ransom: J Comp Neurol 338:141-158, 1993). The combined use of intracellular injection of LRD and confocal imaging significantly improves the resolution of glial cell structure, particularly that of mature astrocytes, for a number of reasons. 1) Single mature dye-filled glia can be imaged, because LRD does not pass through gap junctions. 2) The entire process field of astrocytes can be visualized in a single two-dimensional image. 3) Cell images can be rotated through 360 degrees in all planes to provide a new perspective of glial cell structure in the intact tissue. 4) Reconstruction of optical sections, within a narrow focal plane, provides a high definition and resolution of the finer details of glial morphology. Using these techniques, three astrocyte subclasses were distinguished on morphological criteria. It is the conclusion of this study that the majority of these forms represent a single population of fibrous astrocytes which are well-suited to perform the multiple functions attributed to astrocytes in the CNS. The morphology of mature myelin-forming oligodendrocytes was also described.(ABSTRACT TRUNCATED AT 250 WORDS)

Multiple primary coexisting malignancy in young patients

Two young patients with two coexisting primary malignancy are described. Both of them had colonic carcinoma. In addition, one had pancreatic carcinoma and the other duodenal carcinoma.

Regeneration of axons into the trochlear rootlet after anterior medullary lesions in the rat is specific for ipsilateral IVth nerve motoneurones

The fibre projection from the IVth nerve nucleus to the superior oblique muscle was determined quantitatively in the normal rat by defining fibre numbers in transverse sections of the IVth nerve, and neurone numbers after retrograde labelling by horseradish peroxidase (HRP) injection into the muscle. There were 183 +/- 27 (S.E.) labelled neurones in the nucleus contralateral to the injected muscle and only 2 +/- 1 ipsilateral. The ipsilateral fibre number was 234 +/- 7 and the cell/axon ratio 0.8 +/- 0.1. Extensive analysis of all HRP retrogradely labelled material revealed no central fibre contribution to the IVth nerve other than from neurones resident in the trochlear nucleus. The central portion of the trochlear nerve tract was severed at its point of decussation in the anterior medullary velum. Ninety days after lesion, 10 +/- 4 (6% of control) neurones were labelled in the ipsilateral trochlear nucleus; none were labelled in the contralateral nucleus or in any other part of the midbrain, pons, medulla, or cerebellum. The number of myelinated fibres in the IVth nerve had decreased to 21 +/- 5 (9% of control) so that the cell/axon ratio was 0.4 +/- 0.2, thus suggesting that a single motoneurone has more fibres after lesion. In electron micrographs of the IVth nerve, larger than normal numbers of unmyelinated fibres were seen. Many myelinated fibres displayed signs of abnormal myelination. After regeneration, the projection was exclusively ipsilateral and not crossed as in the normal. These findings establish that there is a high degree of specificity after regeneration since no myelinated central nervous system axons other than trochlear fibres select the IVth nerve root as a trajectory over which to regenerate.

Effects of transforming growth factor beta 1 on scar production in the injured central nervous system of the rat

In the central nervous system (CNS), nerve regeneration after traumatic injury fails. The formation of a dense fibrous scar is thought to restrict in part the growth of axonal projections, providing one of the many reasons that complete lesions of neural pathways in the adult mammalian CNS are rarely followed by significant functional recovery. In order to determine which mechanisms mediate scar formation in the CNS and to investigate whether they can be modulated in vivo, we have attempted to define the potential role of trophic factors. Our previous studies have shown the focal elevation of transforming growth factor beta 1 (TGF beta 1) expression in lesioned CNS tissue. In the studies described here, we demonstrate that TGF beta 1 participates in the scarring response in the rat brain. First, the elevated protein levels of TGF beta 1 are localized to specific populations of injury-responsive cells in the traumatized CNS. Furthermore, the injection of TGF beta 1 into the brains of injured rats causes a dramatic increase in the scarring response. Conversely, when neutralizing TGF beta 1 antibodies are administered, the deposition of fibrous scar tissue and the formation of a limiting glial membrane that borders the lesion is significantly attenuated, thus establishing a role for the endogenous growth factor in regulation of the non-glial component of the scar. In implicating TGF beta 1 in the scarring response in the CNS, the potential use for TGF beta 1 antagonists as inhibitors of scar formation in the injured mammalian CNS is self-evident.

The development of the radial glial scaffold of the cerebellar cortex from GFAP-positive cells in the external granular layer

We have reinvestigated the origin and genesis of the radial glia of the cerebellar cortex in the hamster using three astroglial markers, vimentin, GFAP, and S-100 protein antibodies. On embryonic day 12 (E12), before the emergence of the external granular layer, the cerebellar anlage is traversed from the ventricle to the pial surface by a primordial radial glial scaffold which is vimentin-positive, but GFAP and S-100 negative. With the formation of the external granular layer on E13, a few GFAP positive cells appear among the unstained external granular layer cells. First seen within the germinal trigone and caudalmost part of the external granular layer, they then develop rostrally, amongst the cells of the expanding external granular layer, proliferating adjacent to the basement membrane. Beginning on E15, cells that are positive for the S-100 protein also appear within the external granular layer and the molecular zone. In later stages, S-100 is strongly expressed in Golgi epithelial cells, so we have considered it to be a marker for these cells. By contrast, the primordial radial glial cells were not stained with this marker. On the day of birth (E16/PO) many S-100 positive cells also appear at intermediate levels between the EGL and the Purkinje cell plate. They are unipolar and bear a single radial process that is directed towards the pial surface. The caudorostral appearance of S-100-positive cells firstly in the external granular layer, then in the molecular zone and finally in the Purkinje cell plate is identical to the temporal sequence of development of these layers, and suggests that S-100-positive cells are at first integral constituents of the external granular layer, but later descend through the molecular zone, to colonize the Purkinje cell plate. Here they proliferate and ultimately differentiate into Golgi epithelial cells, their numerous short radial glial processes traversing the molecular zone and the external granular layer to fill the interstices between the primordial radial glial fibres. At birth, S-100-positive Golgi epithelial cells have progressively colonized the Purkinje cell plate from the germinal trigone rostrally, up to a region midway between primary fissure and anterior medullary velum and, between P2 and P3, the rostralmost part of the cerebellum has become populated. GFAP- and S-100-positive cells remain in the external granular layer up to the end of the first postnatal week. In the same interval, the number of Golgi epithelial cells and Bergmann glial fibres increases rapidly in the expanding cerebellar cortex.(ABSTRACT TRUNCATED AT 400 WORDS)

A time course study of the alterations in the development of the hamster cerebellar cortex after destruction of the overlying meningeal cells with 6-hydroxydopamine on the day of birth

This study is a chronological analysis of 6-hydroxydopamine-induced alterations in development of the hamster cerebellar cortex. This treatment destroys the overlying meningeal cells, the sequelae of which include (i) a thinning of the external granular layer over the folial apices and a thickening in the region of the prospective fissures, reflecting a retardation of the growth of the cerebellar cortex, accompanied by displacement of the normally superficialmost GFAP-positive external granular layer cells into deeper parts of the external granular layer; (ii) a retardation of multiplication of Golgi epithelial cells which colonize the rostral third of the Purkinje cell layer so that their numbers decrease in the rostralmost folia; (iii) disturbed morphological and biochemical differentiation of the Golgi epithelial cells and their processes, the growing radial Bergmann glial fibres which detach from the pial surface and branch within the external granular layer, causing a failure in endfeet formation at the superficial glia limitans, loss of characteristic radial morphology, with the adoption of a multipolar form, and normal or increased GFAP expression and decreased S-100 expression; (iv) fragmentation of the external granular layer beyond P5 to P7 with loss of the regular lamination and foliation of the cerebellar cortex, characterized by a completely random distribution of fragments of Purkinje cell layer, molecular zone and internal granular layer. We conclude that the destruction of meningeal cells interferes with the establishment and stabilization of both the external granular layer and the secondary radial glial scaffold composed of Golgi epithelial cells, whose proliferation, growth and differentiation is subsequently disturbed. The failure to stabilize the external granular layer and to form a normal secondary radial glial scaffold is, in turn, responsible for the disruption of the regular laminar deposition of the neurons of the cerebellar cortex.

Meningeal cells organize the superficial glia limitans of the cerebellum and produce components of both the interstitial matrix and the basement membrane

We have investigated the factors controlling both the morphological transformation of glial processes into endfeet and the deposition of extracellular matrix molecules into the overlying basement membrane by destroying meningeal cells over the hamster cerebellum by 6-hydroxydopamine administration on the day of birth. We report that within 24 h of destruction of meningeal cells, the concentrations of fibrillary collagens types I, III and IV in the glia limitans externa and the associated basement membrane molecules laminin, collagen type IV, and fibronectin are greatly diminished, resulting in the development of focal gaps in the basement membrane. The immunohistochemical integrity of the basement membrane is restored within 3 days over those surfaces of the folial apices where meningeal cells reappear. Likewise, the fibrillary collagens of the associated interstitial matrix are re-established in the same amounts as in controls. However, meningeal cells remain permanently absent from fissures and all extracellular matrix molecules tested disappear from rostral cerebellar folia covered by the anterior medullary velum. Moreover, the glial endfeet make up the superficial glia limitans only on folial apices, while they disappear from the fissural surfaces. In primary cultures, meningeal cells produce the fibrillary collagens type I, III, and VI, and the matrix molecules fibronectin and laminin, collagen type IV, nidogen, and heparansulphate proteoglycan. These findings indicate that meningeal cells (i) produce molecular components of both the interstitial matrix and the basement membrane, and (ii) are involved in the morphological transformation of glial fibres into the endfeet which constitute the superficial glia limitans.

Gastrointestinal smooth muscle tumors in children: report of three cases

We report three rare smooth muscle tumors of the gastrointestinal tract (GIT) occurring in infancy. Two were benign leiomyomata and the other a leiomyosarcoma. The imaging features and presentation of leiomyosarcoma in childhood have not been previously described.

Congenital absence of both fibulae in four siblings

Fibular agenesis/hypoplasia is the most common reduction malformation affecting the long bones. Agenesis of both the fibulae, however, is rare, and its occurrence in four consecutive pregnancies has not been reported so far. We report our experience with one such case.

Growth factors in CNS repair and regeneration

Traumatic central nervous system (CNS) injury is a significant clinical problem in the developed world. After injuries that penetrate into either the mature brain or spinal cord, damaged neurons initially begin to regrow, but this regeneration is aborted as a fibrotic scar is laid down within the wound. Reconnection of several neuronal pathways does not occur. Functional recovery from such injuries is therefore poor and morbidity severe, particularly for those patients with spinal cord damage. Although palliative measures are available to improve the quality of life, there is no accepted treatment to restore impaired sensory or motor function, so patients remain significantly and permanently debilitated. However, the rapid recent advances that have been made in our understanding of the underlying cellular and trophic pathology of such injuries offer the potential for development of novel therapies to control scarring, enhance neuron survival and stimulate axon regeneration, thereby promoting functional recovery.

Ventriculo-peritoneal shunt presenting with recurrent pleural effusion: report of a new complication

Ventriculo-peritoneal shunts for hydrocephalus are reported to have a number of complications. We describe an unusual complication not previously listed.

Gastric duplication cyst in children: report of two cases

Gastric duplication cysts (GDCs) in children are rare and are difficult to diagnose. They usually present as an epigastric mass but may be a chance finding. We report two cases and our experience with establishing the diagnosis.

Postoperative bile duct strictures: ultrasound and endoscopic retrograde cholangiopancreatography/percutaneous transhepatic cholangiography evaluation

This retrospective study was undertaken to assess the role of ultrasound (US) and to compare it with endoscopic retrograde cholangiopancreatography (ERCP) and percutaneous transhepatic cholangiography (PTC) in the evaluation of post-operative common bile duct (CBD) strictures. Seventy-four patients with postoperative CBD strictures were evaluated by ERCP and/or PTC. Of these, US scans were available in 52 patients. Ultrasound findings of CBD strictures were: proximal dilatation of CBD with smooth tapering stenosis (41%); abrupt cut off of CBD (18%); and echogenic nodule, without acoustic shadowing, in 16%. Of the remainder, mild proximal dilatation of the CBD was seen in 6%, and 19% of the patients had normal US scans.

No major differences in energy metabolism between matched and unmatched groups of 'large-eating' and 'small-eating' men

Rates of energy expenditure (J/kg fat-free mass (FFM) per min) in normal weight, 'small-eating' men were compared with those obtained for normal weight (n 8) and underweight (n 5) 'large-eating' men. For the matched groups of 'large-' and 'small-eaters' there were no differences in resting metabolic rate (RMR) measurements but during controlled daily activities there was a small but significant increase (P < 0.05) in energy expenditure in the 'large-eaters'. These results contrast with those obtained for the unmatched groups where energy requirements were about 10% (P < 0.01) higher in the underweight 'large-eaters' at rest but were not different during the more energetic (walking) activities. However, after adjustment for differences in FFM between these two groups, the resting energy expenditures of the 'large-eaters' (82.54 (SE 1.51) J/kg FFM per min) were similar to those of the 'small-eaters' (81.87 (SE 1.51) J/kg FFM per min). Oral temperatures were significantly higher in the matched (0.35-0.65 degrees) and unmatched (0.7-0.9 degrees) 'large-eaters' both at rest and during the different activities, but the thermic effect of food (50 kJ/kg FFM) was one fifth lower (not significant) in both groups of 'large-eaters'. These results provide little evidence for any major metabolic differences between groups of 'large-eating' and 'small-eating' men.

Transforming growth factor-beta 1 and basic fibroblast growth factor in the injured CNS

After injuries that penetrate the mature brain or spinal cord, damaged axons initially show a growth response, but later their regeneration is aborted as a dense permanent scar is laid down within the core of the wound. Functional recovery from such injuries is poor and morbidity is severe, particularly for those patients with spinal cord damage. Clinically, no long term therapeutic treatments have been developed that might inhibit scarring and promote neuronal growth. Consequently, the prevalence of patients permanently disabled from head and spinal cord injury is high, estimated at more than 1:1000 of the population of North America (Office of Technology Assessment USA, 1990). Ann Logan and Martin Berry define the mechanisms that underlie the wound healing response in the CNS and discuss the rationale for the development of novel therapeutic strategies.