EXFOLIATIVE CYTOPATHOLOGY OF ALVEOLAR RHABDOMYOSARCOMA

Exfoliative cytopathology of alveolar rhabdomyosarcoma is presented. A 34-year-old male was found to have alveolar rhabdomyosarcoma of the retroperitoneum at autopsy. Ascites was recognized in the course of this disease. Cytological features in the ascites were characterized by relatively small-sized ovoid cells observed singly or in loose clusters. The neoplastic cells possessed small amount of rather vesicular cytoplasm and an eccentric nucleus. The nucleus characteristically revealed multiple deep indentations in the nuclear membrane, a few prominent eosinophilic nucleoli and finely granular or evenly distributed chromatin pattern. These cytological findings, especially the nuclear features, might be useful to differentiate alveolar rhabdomyosarcoma from other neoplasms which consist of relatively small-sized ovoid cells even if the striated muscle origin cannot be confirmed by immunoperoxidase staining.     

Morphological evidence for axonal sprouting of cerebellothalamic neurons in kittens after neonatal hemicerebellectomy

Summary Changes in cerebellothalamic projections in kittens after neonatal hemicerebellectomy were studied by the retrograde and anterograde horseradish peroxidase (HRP)-tract-tracing methods. The number of cerebellar nuclear neurons labeled retrogradely with HRP injected into the ipsilateral VA-VL complex of the thalamus was much more numerous in neonatally hemicerebellectomized kittens than in intact kittens. Presumed terminals of ipsilateral cerebellothalamic fibers labeled anterogradely with HRP injected into the cerebellar nuclei were also distributed more densely and extensively in the thalamic areas, especially in the VA-VL complex, of hemicerebellectomized kittens than in the thalamic areas of the control kittens. These results are in good accordance with those obtained from the previous electrophysiological study (Kawaguchi et al., 1979) and offer corroborating evidence for axonal sprouting of cerebellothalamic neurons after neonatal hemicerebellectomy.     

Two Autopsy Cases of Primary Leiomyosarcoma of the Liver Superiority of Muscle-specific Actin Immunoreactivity in Diagnosis

Two autopsy cases of leiomyosarcoma of the liver in a 49-year old female and 63-year-old male are reported. Both of the liver tumors showed electron microscopically dense patches in the cytoplasm and intermediate junctions between the tumor cells, suggesting a smooth muscle cell origin, irrespective of their different histological features. The nature of both tumors was confirmed by positive immunoreactivity for muscle-specific actin in the tumor cells, whereas desmin immunoreactivity was labile in both cases, showing a higher diagnostic value of the former compared with the latter in these leiomyosarcomas. Both cases, showed extensive distant metastases in spite of an evident difference in their mitotic indices, indicating that this index is not reliable for judging the metastatic potential of these tumors. Acta Pathol Jpn 41: 461–465, 1991.     

Vinyl polymerization. 120. Mutual copolymerization of p-substituted styrenes through radical mechanism

The radical mutual copolymerization of p-substituted styrenes, such as p-methoxy-, p-chloro-, p-bromo-, p-cyanostyrene, and styrene was carried out with one another at 30°C. in the dark. As initiator, azobisisobutyronitrile was used. The plots of the copolymerization rates against HAMMETT 's σ values showed no linear relationships and the concave curves were obtained therefrom. The relative reactivities of p-substituted styrenes with a definite p-substituted polystyryl radical, which were shown by the reciprocal of monomer reactivity ratio r₁, were plotted against σ values and concave curves were also obtained. The relative reactivities of p-substituted polystyryl radicals with p-substituted styrene were calculated from the ratios r₂ and the propagation rate constants in homopolymerization. the plots of them against σ values gave straight lines with different ρ values, according to the polarity of substituents. These results suggest that polar structures in transition state affected markedly the copolymerization rates. The effect of substituents on resonance stabilization was also quantitatively estimated.     

ENCEPHALOMYELONEURITIS WITH MEDIASTINAL GERM CELL TUMOR A Paraneoplastic Condition ?

An unusual case of encephalomyeloneuritis associated with germ cell tumor with mature and immature teratoma arising in the mediastinum is presented. There was an unusually long interval from the onset of neurologic symptoms to the development of malignancy. The histopathology, characterized by limbic encephalitis, brain stem encephalitis, cortical cerebellar degeneration and myeloneuritis, was similar to that of paraneoplastic encephalomyeloneuritis previously described in the literature. Virological and immunological studies failed to demonstrate any causative agents or autoantibodies reacting with brain tissue. The causal relationship between the malignant neoplasm and encephalomyeloneuritis thus seems to be very complex.     

Large aspiny cells in the matrix of the rat neostriatum in vitro: physiological identification, relation to the compartments and excitatory postsynaptic currents.

1. Large aspiny neurons (20-60 microns diam) in the neostriatum were studied in an in vitro rat slice preparation by whole-cell recording to reveal physiological identification from medium-sized spiny projection cells (10-20 microns diam), relation to the patch and matrix compartments, and excitatory synaptic inputs. Recorded cells were identified by intracellular biocytin staining. Compartmental identification was made by calbindinD28K immunohistochemistry in fixed slices. 2. Large stained neurons were morphologically heterogeneous and had aspiny or sparsely spiny dendrites and dense local axonal branches. They were located in the matrix or on the patch-matrix border. Axonal branches of the large aspiny cells were preferentially distributed in the matrix and gave off terminal boutons there. Some of the secondary dendrites arising from stem dendrites running along the border, however, crossed compartment boundaries and made fine branches in a patch. 3. Large aspiny cells had less negative resting membrane potentials and lower thresholds for spike generation than medium spiny cells. They showed longer-duration and larger-amplitude afterhyperpolarizations (AHPs) than medium spiny cells. During hyperpolarizing current pulses, apparent resistance slowly reduced, and a prominent sag was observed in the voltage record, which was absent in medium spiny cells. The large aspiny cells showed no spontaneous firing but had a tendency to fire repetitive spikes in response to depolarizing current pulses, although spike interval tended to increase in later spikes. Spike frequency of large aspiny cells increased less with current intensity than that of medium spiny cells. 4. Most large aspiny cells were considered to belong to a single physiological class, although one large aspiny cells showed shorter-duration AHPs than both most other large aspiny cells and medium spiny cells, and little spike-frequency adaptation. 5. Excitatory postsynaptic currents (EPSCs) of large aspiny cells induced by intrastriatal stimulation had two components. An early, linear component was blocked by 10 microM 6-cyano-7-nitro-quinoxaline-2,3-dione (CNQX), a selective antagonist of non-N-methyl-D-aspartate (NMDA) receptors. A later component with a nonlinear current-voltage (I-V) relationship was blocked by 50 microM DL-2-amino-5-phosphonovaleric acid (DL-APV), a selective antagonist of NMDA receptors. 6. From these results, four conclusions can be drawn. 1) Most large aspiny neostriatal cells in the matrix, although they take heterogeneous shapes, belong to one physiological class with long-duration AHPs and a strong time-dependent component of anomalous rectification.(ABSTRACT TRUNCATED AT 400 WORDS)     

Cell lines that support replication of a novel herpes simplex virus 1 UL31 deletion mutant can properly target UL34 protein to the nuclear rim in the absence of UL31

Previous results indicated that the herpes simplex virus 1 (HSV-1) U(L)31 gene is necessary and sufficient for localization of the U(L)34 protein exclusively to the nuclear membrane of infected Hep2 cells. In the current studies, a bacterial artificial chromosome containing the entire HSV-1 strain F genome was used to construct a recombinant viral genome in which a gene encoding kanamycin resistance was inserted in place of 262 codons of the 306 codon U(L)31 open reading frame. The deletion virus produced virus titers approximately 10- to 50-fold lower in rabbit skin cells, more than 2000-fold lower in Vero cells, and more than 1500-fold lower in CV1 cells, compared to a virus bearing a restored U(L)31 gene. The replication of the U(L)31 deletion virus was restored on U(L)31-complementing cell lines derived either from rabbit skin cells or CV1 cells. Confocal microscopy indicated that the majority of U(L)34 protein localized aberrantly in the cytoplasm and nucleoplasm of Vero cells and CV1 cells, whereas U(L)34 protein localized at the nuclear membrane in rabbit skin cells, and U(L)31 complementing CV1 cells infected with the U(L)31 deletion virus. We conclude that rabbit skin cells encode a function that allows proper localization of U(L)34 protein to the nuclear membrane. We speculate that this function partially complements that of U(L)31 and may explain why U(L)31 is less critical for replication in rabbit skin cells as opposed to Vero and CV1 cells.     

Three-dimensional analysis of alveolar structure in usual interstitial pneumonia

The etiology of usual interstitial pneumonia (UIP), a progressive lung disease, remains unclear. We examined alveolar structure in UIP three-dimensionally. Lung biopsy specimens from five patients with idiopathic pulmonary fibrosis were used. Sections 150-microm thick were stained with elastica solution for elastic fibers, with alpha-smooth muscle actin antibody for myofibroblasts, with anti-Thomsen-Friedenreich antibody for type-II pneumocytes and with anti-CD34 antibody for blood vessels. We examined them three-dimensionally using a laser confocal microscope or light microscope. In the fibrotic lesions, the thick elastic fibers forming the alveolar framework were not particularly dense considering the reduction in alveolar volume. Near the fibrotic lesions, some of the thin elastic fibers in the alveolar wall were slightly sinuous and ended with rounded tips. Type-II pneumocytes had proliferated and were distributed uniformly over the alveolar surface. Smooth muscle actin filaments were detected only around the alveolar orifice. These findings show that in UIP destruction of the elastic fiber framework of the alveoli may lead to irreversible focal alveolar collapse after damage to the alveolar epithelial cells, and proliferation of type-II pneumocytes may be involved with this elastolysis.     

Immunoexpression of the α subunit of a guanine nucleotide-binding protein (Go) in pulmonary neuroendocrine cells and neoplasms

The α subunit of a GTP-blndlng protein, Go, was investigated in pulmonary neuroendocrine neoplasms and fetal tissues of the lung by an immunohistochemlcal method. Positive immunostaining for the α subunit of Go (Goα) was found predominantly on the cell membrane and found occasionally in the cytoplasm. Typical carcinoids were all positively stained (9/9), and small cell carcinoma showed weaker and less frequent staining (5 positive cases in 10). Atypical carcinoids were variously stained (3/4). The tendency for obvious neuroendocrine differentiation to be immunohistochemically determined in typical carcinoids and not in small cell carcinoma is also true of staining for neuron specific enolase (NSE), chromogranin A (CG-A) and synaptophysin. In the lung, Goα-immunostaining was positive not only in nerve tissues but also in the airway epithelium. In the fetal lung, serial sections immunostained for NSE, CG-A and Goα confirmed that Goα-immunoreactive cells belong to the neuroendocrine cell population. The biological significance of Goα is unclear in normal and neoplastic lung tissues, but Goα is a useful marker of neuroendocrine cells and neoplasms of the lung.