Developmental effects of petroleum creosote on mice following oral exposure

Petroleum creosote, dissolved in dimethyl sulfoxide, was administered by gavage to pregnant ICR mice on days 5-9 of gestation at a single dose (400 mg/kg body weight per day). Animals were euthanized on day 17 of gestation, and live fetuses were weighed and examined for skeletal and visceral malformations. Maternal body weights were significantly lowered in both the group administered creosote and the group administered the solvent alone. The number of live fetuses, dead fetuses, resorptions, and the sex ratio in the live fetuses were similar in all groups. Petroleum creosote as administered in this study was not found to be teratogenic in ICR mice.

Expression of the human groEL stress-protein homologue in the brain and spinal cord

A monoclonal antibody (ML30), previously shown to identify a human mitochondrial protein epitope homologous with the groEL heat-shock protein of bacteria (hsp60), was used in an immunohistochemical survey of the central nervous system in patients dying with no evidence of neurological disease and in tissue from patients dying with various neurological disorders. Staining was performed on frozen tissue sections and on formalin fixed, paraffin embedded tissue. Astrocytes in all areas showed a strong pattern of punctate granular staining, which was increased in astrocytes showing reactive changes. Oligodendrocytes stained lightly in a diffuse granular pattern as did most neurons. Ependymal cells showed apical granular positivity. Expression of the hsp60 epitope recognised by ML30 was not seen in ubiquitinated inclusion bodies in motor neuron disease, neurofibrillary tangles in Alzheimer's disease or Lewy bodies in Parkinson's disease. The epitope recognised by ML30 was stable after formalin fixation and in post mortem tissue up to 96 h after death. Expression of the human groEL stress-protein homologue in brain and spinal cord is consistent with a mitochondrial location and may provide a morphological indicator of the functional or metabolic state of cells, especially glial cells.

Strategy and the art of reinventing value

In "From Value Chain to Value Constellation: Designing Interactive Strategy" (July-August 1993), Richard Normann and Rafael Ramírez argue that successful companies increasingly do not just add value, they reinvent it. The key strategic task is to reconfigure roles and relationships among a constellation of actors--suppliers, business partners, customers--in order to mobilize the creation of value in new forms and by new players. What is so different about this new logic of value? It breaks down the distinction between products and services and combines them into activity-based "offerings" from which customers can create value for themselves. But as potential offerings become more complex, so do the relationships necessary to create them. As a result, a company's strategic task becomes the reconfiguration and integration of its compentencies and customers. Normann and Ramírez provide three illustrations of these new rules of strategy. IKEA has blossomed into the world's largest retailer of home furnishings by redefining the relationships and organizational pratices of the furniture business. Danish pharmacies and their national organization have used the opportunity of health care reform to reconfigure their relationships with customers, doctors, hospitals, drug manufacturers, and with Danish and international health organizations.(ABSTRACT TRUNCATED AT 250 WORDS)

Fatal case of echovirus type 9 encephalitis

Enteroviruses are rare causes of acute focal encephalitis. A fatal case of echovirus type 9 infection is reported in a 9 month old boy who presented with a fever and a macular rash followed by two focal seizures. Echovirus type 9 was isolated from lung tissue after seven days.

Myofibroblasts in hollow visceral myopathy: the origin of gastrointestinal fibrosis?

A patient with hollow visceral myopathy is reported in whom light microscopical studies of the small and large intestine showed typical features of degeneration, thinning, and fibrous replacement of smooth muscle of the gastrointestinal tract. Electron microscopy showed a striking increase in collagen with minimal fibroblast proliferation. Smooth muscle fibres had a range of ultrastructural abnormalities including myofilament disarray, electron lucency of the cytoplasm, and proliferation of the endoplasmic reticulum. Some fibres seemed to have typical ultrastructural characteristics of myofibroblasts, and others to be transition forms between typical smooth muscle cells and typical myofibroblasts. It seems likely that the fibrosis typical of this disorder has its origin in the transformation of smooth muscle fibres from a purely contractile to a myofibroblast collagen synthetic phenotype.

Heterotopic neurons in amyotrophic lateral sclerosis

Heterotopic neurons in ALS have suggested aberrant neuronal migration during development. We studied 10 cases with ALS, 10 normal controls, and 10 cases with anterior horn cell disease, including spinal muscular atrophy and acute and remote poliomyelitis. There was no excess of heterotopic neurons in ALS compared with either control group and therefore no failure of neuronal migration in ALS.

Expression of heat shock protein epitopes in renal disease

We have examined the immunohistochemical pattern of staining with antibodies to the 72 kD heat shock protein (HSP72) and ubiquitin in 28 cases of human renal disease. Three distinct patterns of staining were seen with the use of an antibody to HSP72: tubular, intraluminal and interstitial. No glomerular staining was detected. In no cases were ubiquitin epitopes detected. The pattern of staining was most strongly related to the activity of the disease process, positive staining often being present in relation to agents or processes known to upregulate stress protein expression in experimental isolated cellular systems. Stress protein upregulation in human renal disease may represent cellular attempts at cytoprotection in conditions of active sublethal cell toxicity.

Cytoplasmic inclusions in spinal neurons of the motor neuron degeneration (Mnd) mouse. I. Light microscopic analysis

The motor neuron degeneration (Mnd) mutation in the mouse is a late onset, autosomal dominant, neurodegenerative disease in which ventral horn neurons have been shown to contain numerous, large cytoplasmic inclusions. Histochemical and immunocytochemical studies performed on spinal cord from Mnd/Mnd mice in late stages of the disease showed the inclusions to contain protein, lipid and carbohydrate moieties. Spinal neurons, especially those in spinal lamina IX, contained increased beta-glucuronidase activity in the form of large cytoplasmic inclusions. Such inclusions also contained increased acid phosphatase and trimetaphosphatase activity. When immunostained with antiubiquitin antibodies, intracellular ubiquitin deposits were present as accumulations of varying size; some were amorphous while others contained small granules. Extraneuronal ubiquitin deposits were detected in the neuropil. Immunostaining with monoclonal antibody ML30, used here to assay for the presence of a mitochondrial epitope in the inclusions, was widespread and punctate in white and grey matter from Mnd/Mnd and age-matched control spinal cords. The overall pattern of staining was similar for both tissue sources and did not correspond to any of the other probes which reacted with the inclusions in Mnd neurons. The presence of increased levels of lysosomal hydrolases and ubiquitinated molecules suggests that the two general systems for intracellular digestion are activated in Mnd/Mnd spinal neurons.

Association between physical activity and blood pressure in normotensive adults

In 18 normotensive adults (15 women, 3 men), higher levels of habitual physical activity were significantly associated with lower diastolic blood pressure, but not with systolic blood pressure or resting heart rate.

Histochemical and immunocytochemical study of ubiquitinated neuronal inclusions in amyotrophic lateral sclerosis

Ubiquinated cytoplasmic inclusions are a characteristic feature of the anterior horn cell pathology of amyotrophic lateral sclerosis. The underlying abnormality leading to the production of these inclusions in this neurodegenerative motor system disease is unknown. Despite the application of a wide range of histochemical and immunocytochemical techniques we have been unable to identify a core constituent protein in these intraneuronal inclusions. A novel approach to this problem is required.

The detection of breast cancer after augmentation mammaplasty

Thirty-five patients treated for 37 cases of breast cancer after augmentation mammaplasty were analyzed. All augmentations were performed with silicone gel prostheses at a mean age of 38 years (range 24 to 59 years). The mean interval from breast augmentation to the detection of breast cancer was 7.5 years. Physical examination demonstrated a palpable breast mass in 35 of the 37 cases (95 percent). The pathologic staging was in situ 3 (8 percent), local 18 (49 percent), and nonlocal 16 (43 percent). Standard compression mammography was performed in 31 patients prior to breast biopsy. Abnormalities were detected in 17 (54.8 percent). Palpable masses were visualized in only 12 (38.7 percent). Ultrasound was utilized successfully in 3 patients with palpable masses to guide fine-needle aspiration biopsy. Standard two-view mammography has a low sensitivity in detecting palpable cancers in patients who have undergone augmentation mammaplasty. Ultrasound should be evaluated as a routine adjunctive screening method in this group of patients. The clinical detection of breast cancer, as evidenced by pathologic staging, is not delayed.

Sorbitol content of selected oral liquids

OBJECTIVE

Excipients in pharmaceuticals usually are considered inert, and may be overlooked in the differential diagnosis of diarrhea. Sorbitol-containing medicinal liquids are capable of inducing osmotic diarrhea. We reviewed the oral liquids in our formulary to determine their sorbitol content and to evaluate the availability of this information.

DESIGN

The oral liquids stocked by our hospital were determined through a computer search and manual inspection of the pharmacy storeroom. Three common sources of drug information were consulted to determine each product's sorbitol content: manufacturers' product information, American Hospital Formulary Service (AHFS) Drug Information 91, and Facts and Comparisons Drug Information. We then contacted each manufacturer by mail or telephone to verify the information.

SETTING

The study was conducted at the University of Cincinnati Hospital, a tertiary-care, teaching hospital.

RESULTS

A total of 129 products (98 chemical entities) were reviewed. Fifty-four (42 percent) of the products examined contained sorbitol. The frequency of sorbitol presence by liquid type was: solutions (33 percent), suspensions (43 percent), syrups (59 percent), elixirs (43 percent), concentrates (67 percent), drops (33 percent), tinctures (0 percent), and emulsions (0 percent). The percentage of listings indicating the presence of sorbitol was: manufacturer's product information (79 percent), Facts and Comparisons (52 percent), and AHFS Drug Information 91 (13 percent). Only three of the 54 products had the exact sorbitol content stated in any source.

In vitro embryotoxicity of petroleum creosote monitored via mouse preimplantation embryo culture

A mouse preimplantation embryo culture system was utilized to characterize the in vitro embryotoxicity of petroleum creosote (PC), a complex mixture of aliphatic and polycyclic aromatic hydrocarbons. ICR mouse embryos, collected on d 3.5 of gestation (blastocyst stage), were exposed for 1 h to varying concentrations of petroleum creosote in serum-supplemented culture medium. Parallel embryo cultures were exposed to PC in medium supplemented with rodent hepatic S9 microsomal fractions to monitor the role of bioactivation in PC-induced embryotoxicity. Embryos were subsequently cultured in control medium for 72 h and observed for viability as well as specific, time-dependent developmental end points--hatching and attachment to the culture dish at 48 h, and trophoblastic outgrowth with a distinct inner cell mass at 72 h. Embryonic viability varied in inverse proportion to PC concentration. Petroleum creosote caused embryolethal effects at concentrations of 33 micrograms/ml of culture medium and 54 micrograms/ml. Embryotoxicity was not observed at 22 micrograms/ml. Culture supplementation with rodent hepatic S9 fractions did not modify, either qualitatively or quantitatively, the embryotoxicity of PC in vitro. These findings implicate PC as a prenatal toxicant and support environmental and human health concerns regarding PC exposure from PC-containing chemical waste sites.

Ultrastructure of pre-synaptic input to motor neurons in Onuf's nucleus: controls and motor neuron disease

Ultrastructural analyses of sphincteric motoneurons in Onuf's nucleus at S2 were undertaken in human spinal cord obtained 3-6 h post-mortem from three subjects with no neurological disease ('controls') and five in which death was due to motor neuron disease (MND). Neurons in specified locations within Onuf's nucleus of control subjects ranged between 17.8 and 71.7 microns diameter (mean 38.6 microns). Analyses of synaptology revealed five ultrastructural classes of presynaptic terminal synapsing with the neuronal surface membrane. When classified by size, vesicle morphology, and synaptic site structure these conformed to the S, F, T, M and C-terminals defining somatic motoneurons. No terminals characteristic of autonomic motoneurons were found. In MND subjects, neurons in Onuf's nucleus at S2 were preserved despite a paucity of neurons in medial and lateral motor nuclei and were of similar size range to those in control subjects. The morphological classes of pre-synaptic terminal found in controls, also characterized sphincteric motoneurons in MND subjects, including the C-type terminal. The presence of C-terminals indicates (i) that sphincteric motoneurons are somatic alpha-motoneurons, and (ii) that hypotheses explaining the survival of sphincteric motoneurons in MND on the basis of Onuf's nucleus being an extension of the pre-ganglionic parasympathetic nucleus, or having intrinsic autonomic properties are incorrect.

Hypertrophy without increased isometric strength after weight training

Eight men (20-23 years) weight trained 3 days.week-1 for 19 weeks. Training sessions consisted of six sets of a leg press exercise (simultaneous hip and knee extension and ankle plantar flexion) on a weight machine, the last three sets with the heaviest weight that could be used for 7-20 repetitions. In comparison to a control group (n = 6) only the trained group increased (P less than 0.01) weight lifting performance (heaviest weight lifted for one repetition, 29%), and left and right knee extensor cross-sectional area (CAT scanning and computerized planimetry, 11%, P less than 0.05). In contrast, training caused no increase in maximal voluntary isometric knee extension strength, electrically evoked knee extensor peak twitch torque, and knee extensor motor unit activation (interpolated twitch method). These data indicate that a moderate but significant amount of hypertrophy induced by weight training does not necessarily increase performance in an isometric strength task different from the training task but involving the same muscle group. The failure of evoked twitch torque to increase despite hypertrophy may further indicate that moderate hypertrophy in the early stage of strength training may not necessarily cause an increase in intrinsic muscle force generating capacity.

Blackbody source in the -50 to +200 degrees C range for the calibration of radiometers and radiation thermometers

A high-accuracy, large-aperture calibration source for radiometers and infrared radiation pyrometers operating in the range from -50 to +200 degrees C is described. It is shown that by means of reflecting surfaces inside the blackbody the requirements for temperature uniformity can be substantially relaxed while high accuracy in the characterization of the effectivet emperaturei s maintained.

Purkinje cell toxicity of beta-aminopropionitrile in the rat

Compounds causing neurolathyrism are putative aetiological agents in neurodegenerative disorders including amyotrophic lateral sclerosis. beta-Aminopropionitrile (BAPN) is one such compound. We have administered this lathyrogenic agent at a dose of 1 g/kg by the intraperitoneal route in experiments in adult Sprague-Dawley rats during a period of 10 weeks. The rats developed marked kyphoscoliosis, ataxia with paralysis and muscle wasting of the hind limbs. Vacuolation and loss of Purkinje cells developed, but no anterior horn cell degeneration was noted. Immunohistochemical studies of phosphorylated neurofilaments and the 72 kDa heat shock protein were normal and no intraneuronal ubiquitinated inclusions were seen. High-dose intraperitoneal BAPN in the rat causes Purkinje cell changes, but no other central nervous system abnormalities.