Polyamines and NMDA receptors modulate pericapillary astrocyte swelling following cerebral cryo-injury in the rat

Four hours following cryo-injury rat cerebral pericapillary astrocytes from the perilesional area were markedly swollen occupying 17% of the pericapillary space as compared to 11% in sham operated controls. Ornithine decarboxylase activity and polyamine levels were increased over sham controls. The astrocytic swelling, the percentage of the pericapillary space occupied by astrocytic processes, and polyamine levels were reduced to near control levels by the following: (1) alpha-difluoromethylornithine; (2) Ifenprodil; and (3) MK-801. alpha-Difluoromethylornithine is a specific inhibitor of ornithine decarboxylase, Ifenprodil is an inhibitor of the polyamine binding site on the n-methyl-d-aspartate receptor, and MK-801 is an antagonist to n-methyl-d-aspartate binding to the n-methyl-d-aspartate receptor. Addition of putrescine, the product of ornithine decarboxylase activity, reversed the effect of alpha-difluoromethylornithine and restored the pericapillary swelling. Putrescine did not affect the MK-801-induced reduction in pericapillary astrocytic swelling. Therefore, polyamines and the n-methyl-d-aspartate receptor modulate excitotoxic responses to cryo-injury in pericapillary cerebral astrocytes.

Isolated myocardial abscess causing coronary artery rupture and fatal hemopericardium

We report a rare case of cardiac tamponade caused by hemopericardium secondary to erosion and rupture of a coronary artery by an adjacent solitary myocardial abscess. The resulting tamponade led to the sudden death of this 46-year-old man. Antemortem blood culture and the postmortem microscopic examination of the myocardial abscess revealed the causative agent to be Staphylococcus aureus. Hemopericardium due to ventricular wall rupture secondary to a myocardial abscess has been infrequently reported, but, to our knowledge, only one other report of hemopericardium due to coronary artery rupture related to myocardial abscess has been published.

Morphology and morphometry of motor endings on macaque intrafusal fibers

The ultrastructural studies have shown three types of motor endings in the macaque intrafusal fibers: 1) unindented axon terminals with smooth or shallowly folded postsynaptic membrane; 2) indented terminals with few postsynaptic folds; and 3) indented terminals with heavily folded postsynaptic membrane. The terminals on bag 1 and chain fibers were generally more indented than those on the bag 2 fibers. Deeply indented terminals with highly folded postsynaptic membranes were noticed on the bag 1 and chain endings in spindles from lumbrical but not the biceps muscle. In the individual intrafusal fibers from the biceps and lumbrical spindles, the degree of indentation did not correlate with the extent of postsynaptic folding (P greater than .01). Endings on bag 1 and chain fibers in the lumbrical spindles showed a positive correlation between indentation of terminals and their distance from the primary sensory endings (P less than .01), whereas the lumbrical bag 2 endings and the biceps intrafusal endings did not (P greater than .01). The shape of the intrafusal motor endings thus is independent of their location but dependent on the type of intrafusal fibers.

Hepatic abscess resulting from gastric perforation of a foreign object

A case of a patient with a hepatic abscess secondary to a fish or chicken bone is presented. Of interest is the fact that the abscess resulted from gastrointestinal perforation of the foreign object. A review of the literature of this unusual occurrence along with clues to making the diagnosis are discussed.

Resistance and allergy to recombinant human insulin

Insulin allergy and antibody-mediated resistance may complicate therapy with animal insulins. We describe a 53-year-old man manifesting both resistance and persistent systemic allergy despite treatment with recombinant human insulin. Insulin resistance and symptoms of allergy appeared in this patient several months after initiating therapy with mixed beef-pork insulin, as is often the case. Symptoms initially improved, but persisted, and then worsened again, despite continuous human insulin therapy. Total insulin-binding capacity by Scatchard analysis, high plasma insulin-binding capacity, and specific anti-insulin antibody levels were consistent with an immunologic form of insulin resistance. Glucocorticoid therapy was required both to reduce allergic findings and to restore glycemic control. Although recently available human insulins may be less immunogenic than animal forms, immune responses to exogenous human insulin still may pose significant clinical problems.

Variability of mitochondrial cytochemistry in human neuromuscular diseases

This study describes mitochondrial cytochemistry with reference to cytochrome c oxidase and NADH oxidase activities as well as calcium localization at subcellular level in a variety of human mitochondrial disorders. The enzyme activities, calcium homeostasis, and myofibrillary architecture were retained in the lipid storage myopathies with carnitine and carnitine palmityl transferase deficiency. The loss of enzyme reaction, excessive Ca++ deposit, and myonecrosis were the features of the group comprised of a variety of disorders with mitochondrial pathology (Kearns-Sayre's syndrome, chronic progressive ophthalmoplegia, polymyositis, neurogenic atrophy, and fascioscapulo humeral dystrophy). Based on these and our previous experimental study (Shah et al., 1985), we suggest that the human mitochondrial disorders may be grouped into two types: one in which the morphologically altered mitochondria retain the enzyme activities and Ca++ homeostasis and the other in which the altered mitochondria associated with muscle necrosis represent the loss/reduction of the enzyme activities as well as Ca++ homeostasis.

Attachments of human intrafusal fibers

The human intrafusal fibers have two major types of attachments: (1) extracapsular, involving the bag and long chain fibers which tapered into the extrafusal endomysium; and (2) intracapsular, involving only the short chain fibers which attached to the outer or inner capsule as well as to the bag, and other chain fibers. At all the attachment sites except the interfiber attachments, the intrafusal fibers showed alterations in the basement and plasma membrane, streaming of the Z band, and rod bodies. This profile was similar to the myotendinous junctions. The terminal sarcomere segment consisted of the actin filaments, thickening of the plasma membrane, and folded basal lamina. The interfiber attachments were of two types--the gap and tight junctions. There were thus two major functional types of attachment, the myotendinous type contacts which were mechanical and the interfiber attachments which represent electrical continuity between the two chain fibers.

Morphology and morphometry of motor endings in primate intrafusal fibers

The pre- and postsynaptic structure of 243 axon terminals of bag 1, bag 2, and chain fibers were studied in cynomolgus monkey skeletal muscle spindles. The motor endings of the biceps and gastrocnemius spindles (long limb muscle) were compared to the motor endings of lumbricals and opponens pollicis (intrinsic hand muscle) spindles. In both muscle groups the only significant difference observed in the presynaptic features was in the presynaptic membrane length. The postsynaptic features of bag 1, bag 2 and chain endings were similar in the long limb muscle spindles. In the intrinsic hand muscle, however, the bag 1 and chain endings showed complex postsynaptic structure which resembled the extra fusal endings while the postsynaptic structure of bag 2 endings was much simpler. From these studies we conclude that the postsynaptic structure of various intrafusal fiber types is dissimilar in different muscles.

Mitochondrial cytochemistry in experimental myopathies

In this paper, we have described mitochondrial cytochemistry (NADH oxidase, cytochrome c oxidase), in the light and electron microscopic studies of the experimental mitochondrial myopathies. DNP, oleate and crotoxin were employed to produce mitochondrial changes in the rat skeletal muscle. The DNP and oleic acid lesions showed strong NADH oxidase and cytochrome c oxidase activities in mitochondria--both at the light microscopic as well as at ultrastructural level. However, the crotoxin lesions showed marked reduction of both the enzyme activities in histochemistry and electron microscopy. Muscle necrosis was seen only in the crotoxin lesion. On the basis of these data, we propose that DNP and oleic acid treatment produced mitochondrial myopathies in which the mitochondrial structure was altered but they were enzymatically active, while the crotoxin treatment produced the structural and enzymatic alterations of the mitochondria.

Cytologic diagnosis of renal carcinoma in the presence of inferior vena cava obstruction: case report

Diagnostic work-up and staging of patients with renal tumors usually includes inferior vena cavography. In this case, complete occlusion of the cava was demonstrated by cavography while catheter aspiration yielded tumor fragments diagnostic of renal adenocarcinoma. Transcatheter aspiration in the presence of caval obstruction can provide preoperative tissue diagnosis as well as accurate tumor staging information.

Skeletal muscle in preterm infants with congenital myotonic dystrophy. Morphologic and histochemical study

The skeletal muscle in 3 preterm infants (27, 34, 37 weeks gestation age) born to mothers with myotonic dystrophy showed a syncytial pattern at 27 weeks and a decreasing percentage of satellite cells and central nuclei at 34 and 37 weeks gestation. The fiber type differentiation was observed only at 37 weeks of gestational age. In all 3 cases muscle fibers with multiple acid phosphatase positive were seen. The muscle spindles also had thick capsules and showed lack of morphologic and histochemical differentiation into fiber types. These findings suggest immaturity of skeletal muscle in comparison to the normal. The immaturity of the skeletal muscle correlated well with the prognosis of the patients.

Ultrastructure of muscle spindle in congenital myotonic dystrophy. A study of preterm infant muscle spindles

The muscle spindle in the preterm infants with congenital myotonic dystrophy consisted of numerous, unfused intrafusal fibers. These fibers showed immature myofilament arrangement at 27 weeks but had the nuclear arrangement of bag and chain type. The motor endings were very sparse while prominent sensory endings were seen. At 34-37 weeks, even though the muscle fibers were unfused, the nuclear bag and chain fibers could be differentiated by the presence and absence of M line. Immature motor endings were seen at this stage. In conclusion, the muscle spindle in the preterm infants is immature.

Morphological and histochemical correlation of recovery after spinal transection in rat

Previous studies from our laboratory have shown disappearance of aminergic terminals with relative preservation of cholinergic activity below the level of the lesion (Rodriques & Sahgal, 1978). Since then we have extended our study to look at the behaviour of aminergic fibres and neurons at various time intervals following the lesion and attempted to correlate with the functional recovery. Three to 4 weeks after spinal transection (thoracic), the rats started to show spinal-stepping which became stronger and dexterous with the passage of time. Up to 6 months after thoracic transection, maximum recovery was observed. Studies of catecholamine fluorescence revealed proliferation of new aminergic terminals which were observed four or five segments below the transection. These observations demonstrate regeneration of aminergic fibres in rat. The significance of the data in the light of neurophysiologic studies will be discussed.

Osteosarcoma complicating Paget's disease of the spine with neurologic complications

An osteosarcoma with neurologic manifestations complicated Paget's disease of the lumbar spine in a 63-year-old man. Initially without demonstrable metastasis, the patient was treated by decompressive laminectomy followed by radiation and adjuvant chemotherapy (COMPADRI-1 regimen). While such treatment may not be curative, there are significant palliative benefits.

Ocular manifestations of toxic epidermal necrolysis associated with allopurinol use

A 54-year-old man was receiving allopurinol therapy to treat hyperuricemia that followed an inferior wall, myocardial infarction. After three weeks of allopurinol therapy, the patient developed signs and symptoms of toxic epidermal necrolysis that included pseudomembranous conjunctivitis with ulcerative lesions on the lids and conjunctiva, and punctate corneal staining with subsequent corneal abrasions. Treatment with topical antibiotics and artificial tears relieved the symptoms somewhat, but punctate staining and dry eyes persisted after 14 months of follow-up. Bilateral corneal ulcers developed and necessitated conjunctival flaps in each eye. Visual acuity in each eye was 20/40.

Small cell carcinoma of the male breast: report of a case

An uncommon type of breast carconoma in a male studied by light and electron microscopy, is reported. Light microscopy reveals histologic characteristics and a pattern similar to infiltrating lobular carcinoma in the female breast. The ultrastructural study, because of close similarities in cellular characteristics with previously published reports, gives firm support to the light microscope findings.

Department of Neurology, Northwestern University Medical School, Chicago, Illinois

A case of non-progressive congenital myopathy is described in which there was absence of muscles and scapulo-peroneal distribution of weakness. The muscle biopsy showed preferential atrophy of Type I fibers and subsarcolemal bodies. These bodies were composed of an acidic protein with sulphahydryl groups which showed acid stable adenosine triphosphatase activity. The possibility of a maturational arrest as a cause is presented.