Inflammatory pseudotumor of lymph nodes: clinicopathologic and immunohistological study of 11 Japanese cases

We report 11 Japanese cases of inflammatory pseudotumor (IPT) of the lymph node. There were 7 males and 4 females with ages ranging from 5 to 68 years (median; 48). Only 2 patients had systemic lymphadenopathy, and all others had involvement of only 1 lymph node group. Constitutional symptoms such as fever were present in 8 patients and laboratory abnormalities were detected in 5. All patients recovered and were alive and well after 2 to 180 months (median; 32 months). Histologically, the process mainly involved the connective tissue framework of the lymph node, secondarily spreading into the lymph node parenchyma and the perinodal tissue. It was characterized by a storiform growth pattern of myofibroblasts, marked vascularity with associated vascular lesions, and a polymorphous reactive cellular infiltrate in a collagen-rich stroma. An immunohistochemical study revealed numerous myofibroblasts, histiocytes, and vascular endothelial cells expressing vascular endothelial growth factor (VEGF) in 6 cases. It was suggested that VEGF may be involved, in part, in the induction of the angiogenesis of IPT. Moreover, the present study indicates that follicular dendritic cell sarcoma, nasal T/natural killer cell lymphoma, and anaplastic large cell lymphoma should be added to the differential diagnosis from IPT of the lymph node. Int J Surg Pathol 9(3):207-214, 2001     

F-waves of the facial muscles in healthy control subjects and in patients with peripheral facial nerve disturbance

F-waves were recorded from the mentalis muscles with surface electrodes following stimulation of the marginal mandibular branch of the facial nerve in healthy control subjects during wakefulness, non-REM (rapid eye movement) sleep and voluntary contraction and in patients with Bell's palsy and acoustic neurinoma. The F-wave of the facial muscles results from the backfiring of antidromically activated alpha motoneurons in the facial motonucleus. Therefore, first, the F-waves were not easily elicited in patients with any disturbance in the proximal segment of the facial nerve (Bell's palsy and acoustic neurinoma). Second, the F-waves were affected by excitability of the facial motonucleus; the F-waves were inhibited significantly during sleep and enhanced significantly during voluntary contraction compared with those at rest during wakefulness. When the stimulation strength was set submaximum for M-waves, F-waves were elicited but H-waves, which have lower threshold than M-waves, were not elicited in the facial muscles, unlike the case of the extremities. Measurement of the F-waves of facial muscles is a new method for estimating excitability of the facial motonucleus unless there is any disturbance of the proximal segment. Fundamental characteristics of the facial F-waves were shown in the present study and measuring facial F-waves is clinically applicable for investigation of both excitability of the facial motonucleus and facial peripheral nerve disturbance.     

Fine mapping of a gene responsible for regulating dietary cholesterol absorption; founder effects underlie cases of phytosterolaemia in multiple communities

Sitosterolaemia (also known as phytosterolaemia, MIM 210250) is a rare recessive autosomal inherited disorder, characterised by the presence of tendon and tuberous xanthomas, accelerated atherosclerosis and premature coronary artery disease. The defective gene is hypothesised to play an important role in regulating dietary sterol absorption and biliary secretion, thus defining a molecular mechanism whereby this physiological process is carried out. The disease locus was localised previously to chromosome 2p21, in a 15 cM interval between microsatellite markers D2S1788 and D2S1352 (based upon 10 families, maximum lodscore 4.49). In this study, we have extended these studies to include 30 families assembled from around the world. A maximum multipoint lodscore of 11.49 was obtained for marker D2S2998. Homozygosity and haplotype sharing was identified in probands from non-consanguineous marriages from a number of families, strongly supporting the existence of a founder effect among various populations. Additionally, based upon both genealogies, as well as genotyping, two Amish/Mennonite families, that were previously thought not to be related, appear to indicate a founder effect in this population as well. Using both homozygosity mapping, as well as informative recombination events, the sitosterolaemia gene is located at a region defined by markers D2S2294 and Afm210xe9, a distance of less than 2 cM.     

Eosinophilic neuronal inclusion bodies in the temporal lobe.

Intracytoplasmic neuronal inclusion bodies were found in the temporal lobe of an elderly woman. The oval or rod-shaped inclusion bodies were eosinophilic, showed bright red staining with azan, and were about half the size of the nucleus of a large neuron. They were non-argyrophilic and non-congophilic. Ultrastructurally, the inclusion bodies consisted of aggregates of filamentous materials showing partial periodicity. Among inclusion bodies reported up to now, the present ones resembled some described previously as "thalamic inclusions", but were different with regard to their partial filament periodicity, and unusual in that they were located in the deep layer of the temporal lobe and not in the thalamic nuclei.     

Aplastic anemia: lack of increase of in vitro colony formation after T cell depletion with monoclonal antibodies and complement

To detect suppressor T cells to hematopoietic stem cells, growth of granulocyte-macrophage colony-forming cells (CFU-GM) and burst-forming unit (BFU-E) was compared before and after treatment of bone marrow cells with anti-T monoclonal antibodies and complement in 29 patients with aplastic anemia. The anti-T monoclonal antibodies used were 35.1 (CD2), Tp120 (CD6) and ATL27 (not clustered). Treatment of normal bone marrow with anti-T monoclonal antibodies and complement resulted in complete (greater than 99%) lysis of T cells with negligible effects on colony growth. Preincubation of marrow samples with monoclonal antibodies and complement did not enhance CFU-GM or BFU-E colony growth in patients with aplastic anemia. Using this assay, there was no evidence of T cell-mediated inhibition of colony proliferation in any of 29 patients.     

Characterization of a helper T cell epitope recognized by mice of a low responder major histocompatibility type.

Most known helper T cell (Th) epitopes studied have naturally been immunodominant epitopes recognized by T cells from animals of high responder major histocompatibility complex (MHC) haplotype. We have previously found that most such immunodominant Th epitopes tend to be amphipathic alpha helices, that is, helices with hydrophobic residues on one side and hydrophilic residues on the other, and the corresponding peptide can usually elicit a response to the native protein. However, very few epitopes seen by MHC low responder T cells have been identified. Within the CNBr fragment of residues 1-55 of sperm whale myoglobin (SwMb), a Th epitope is known to exist that stimulates T cells from low responder H-2k mice, but it has not yet been localized to a length of 8-12 residues, the usual length of a Th epitope. To determine whether this low responder epitope would have similar properties, we located it using 10 evenly overlapping 15-residue peptides that span the region. Analysis of this region by the computer program predicted the site covered by two peptides (residues 26-40 and 31-45 which overlap by 10 residues) to be the most likely site for a Th epitope. Of the 10 peptides tested experimentally, only one peptide (residues 26-40) was able to stimulate two low responder Th clones that are specific for the 1-55 region. The peptide was able to prime T cells of low responder B10.BR mice in vivo for in vitro response to the native SwMb as well as to the peptide fragment of residues 1-55. Immunization of low responder mice with SwMb showed that, of the 10 overlapping peptides, the major site of response within the 1-55 region is to the identified peptide. Finally, an extended peptide of residues 24-42 was made to increase the amphipathic score. This extended peptide induced greater proliferation of the clones. Thus, this low responder epitope has properties similar to those of immunodominant epitopes recognized by high responders.     

Vinyl polymerization by metal complexes, 30. On the initiation mechanism of vinyl polymerization by the system copper(II) chelate of poly(vinyl alcohol)/carbon tetrachloride: Spin trapping and gelation studies

The initiation mechanism of vinyl polymerization by a copper(II) chelate of poly(vinyl alcohol) was studied in aqueous solution in the presence of carbon tetrachloride, in order to determine the free radical species formed during the initiation step. Trichloromethyl radicals were ascertained to be the main initiation species, by spin trapping and gelation experiments. Differences in polymerization activity between methyl methacrylate and acrylonitrile are discussed.     

Morphometric analysis of the thoracic and lumbar spine in Japanese on the use of pedicle screws

The pedicle screw and hook have become popular instruments in treating spinal deformity and disease. This study gathered morphological data on thoracic and lumbar spines in a Japanese population that should serve as useful reference for posterior instrumentation surgery. One hundred and three dry bones were used to investigate the morphology of pedicle and facet in thoracic and lumbar spines. Measurements included the diameter and axial length of pedicle from T8 to L5, height and width of facets and thickness of articular processes from T1 to T12, and axial angle of pedicle from T1 to L5. The diameter and axial length of pedicle were smallest at T8, diameter was largest at L5 and axial length was largest at L3. Height of facets and thickness of articular processes were largest at T12. Men tended to have larger pedicles and facets than women. Transverse angle of pedicle was smallest at T12. These precise data may provide useful information when performing posterior instrumentation surgery and when developing new spinal implant systems for Asians.     

Observation of cavitation in a mechanical heart valve in a total artificial heart

Recently, cavitation on the surface of mechanical heart valves has been studied as a cause of fractures occurring in implanted mechanical heart valves. The cause of cavitation in mechanical heart valves was investigated using the 25 mm Medtronic Hall valve and the 23 mm Omnicarbon valve. Closing of these valves in the mitral position was simulated in an electrohydraulic totally artificial heart. Tests were conducted under physiologic pressures at heart rates from 60 to 100 beats per minute with cardiac outputs from 4.8 to 7.7 L/min. The disk closing motion was measured by a laser displacement sensor. A high-speed video camera was used to observe the cavitation bubbles in the mechanical heart valves. The maximum closing velocity of the Omnicarbon valve was faster than that of the Medtronic Hall valve. In both valves, the closing velocity of the leaflet, used as the cavitation threshold, was approximately 1.3-1.5 m/s. In the case of the Medtronic Hall valve, cavitation bubbles were generated by the squeeze flow and by the effects of the venturi and the water hammer. With the Omnicarbon valve, the cavitation bubbles were generated by the squeeze flow and the water hammer. The mechanism leading to the development of cavitation bubbles depended on the valve closing velocity and the valve stop geometry. Most of the cavitation bubbles were observed around the valve stop and were generated by the squeeze flow.