Endovascular Cerebral Venous Sinus Imaging with Optical Coherence Tomography.

BACKGROUND AND PURPOSE: Imaging of the cerebral venous sinuses has evolved Substantially during the past 2 decades, and most recently intravascular sinus imaging with sonography has shed light on the pathophysiology of sinus thrombosis and intracranial hypertension. Optical coherence tomography is the highest resolution intravascular imaging technique available but has not been previously used in cerebral sinus imaging. The purpose of this study was to develop a preclinical animal model of endovascular optical coherence tomography cerebral venous sinus imaging and compare optical coherence tomography findings with histology. MATERIALS AND METHODS: Four consecutive Yorkshire swine were selected. The superior sagittal sinus was first catheterized with a microwire, and the optical coherence tomography catheter was delivered via a monorail technique into the sinus. Luminal blood was cleared with a single arterial injection. After structural and Doppler optical coherence tomography imaging, a craniotomy was performed and the sinus and adjacent dura/veins were resected. Bland-Altman analysis was performed to compare optical coherence tomography and histology. RESULTS: Technically successful optical coherence tomography images were obtained in 3 of 4 swine. The luminal environment and visualization of dural arteries and draining cortical veins were characterized. The average maximum diameters of the sinus, dural arteries, and cortical veins were 3.14 mm, 135 µm, and 260 µm, respectively. Bland-Altman analysis demonstrated good agreement between histology and optical coherence tomography images. CONCLUSIONS: Endovascular optical coherence tomography imaging was feasible in this preclinical animal study. Adoption of this imaging technique in the human cerebral venous sinus could aid in the diagnosis, treatment, and understanding of the pathophysiology of various diseases of the sinus. Human safety and feasibility studies are needed.

DNA polymerase beta gene mutation in human prostate cancer.

DNA polymerase beta is a nuclear protein essential to DNA repair in mammalian cells. A high frequency of mutations in this gene has been reported in colorectal cancers. To clarify the tumorigenesis steps of human prostate cancers in the molecular basis, we examined the entire coding region of the human DNA polymerase beta gene in human prostate cancer tissues using polymerase chain reaction, single-strand conformational polymorphism analysis of RNA, and sequencing analysis. Consequently, we detected DNA polymerase beta gene mutations in 2 of 12 cases (17%). The first case is an A to G transition at nucleotide 893, resulting in a substitution of the amino acid from tyrosine to cysteine. In the second case, we found an A to G transition at nucleotide 305, a T deletion at nucleotide 569, and an A insertion into the 6 repeats of A from nucleotide 612 to 617. This T deletion shifted the subsequent reading frame and resulted in the premature termination at codon 163 instead of 336. The two cases were advanced grade and stage. Present results suggest that polymerase beta gene mutations, although they occurred at relatively low frequency, are involved in certain cases of human prostate carcinogenesis.

Membrane-anchored forms of EGF stimulate focus formation and intercellular communication.

Epidermal growth factor (EGF) is the prototype for a small family of soluble proteins that bind to and activate the EGF receptor. These proteins are derived from larger propeptides that are anchored to the plasma membrane. Although the signalling properties of soluble EGF are well-characterized, the signalling potential of the membrane-anchored form had not been determined. We therefore investigated whether membrane-anchored EGF can stimulate the EGF receptor. An EGF mini-gene expression system that we had previously constructed for expression of soluble EGF was modified to encode anchored forms of EGF. In the encoded proteins EGF was fused to the spacer in the EGF propeptide that separates EGF from the transmembrane domain. The spacer was followed by vesicular stomatitis virus G protein transmembrane and cytoplasmic domain sequences. Three forms of EGF/G fusion protein were expressed in rat fibroblasts. The plasmids for expression of anchored EGF induced focus formation in rat fibroblasts, indicating that anchored EGF can cause autocrine transformation. When mixed with indicator HeLa cells, cell lines expressing EGF/G fusion proteins activated the HeLa EGF receptor. This activation was mediated by cell-associated, rather than soluble EGF. The finding that membrane-anchored EGF is capable of activating the EGF receptor on neighboring cells has broad implications for the functions of EGF in the organism.

GLP-I(7-36) amide augments Ba2+ current through L-type Ca2+ channel of rat pancreatic beta-cell in a cAMP-dependent manner.

The whole-cell patch-clamp method was used to examine the effect of glucagon-like peptide I (GLP-I)(7-36) amide on the activation process of L-type Ca2+ channels of rat pancreatic beta-cells. After depolarization, GLP-I (1-100 nmol/l) caused action potentials in cells exposed to a glucose-free solution for 10 min. The percentage of cells producing action potential depended on the concentration of GLP-I. In some cells, GLP-I caused action potentials without the prior depolarization of the membrane. In cells exposed to the glucose-free solution for longer than 30 min, or in cells that were deprived of ATP by a means of the conventional whole-cell configuration, GLP-I (20 nmol/l) did not cause the electrical excitation. Application of GLP-I augmented the maximum Ba2+ current (IBa) through L-type Ca2+ channels and shifted the current voltage curve to the left. Values of changes in the maximum IBa depended on GLP-I concentration. Application of dibutyryl cAMP (dbcAMP, 1 mmol/l) also augmented IBa. In cells pretreated with Rp-cAMP, dbcAMP did not change the magnitude of IBa. Also in cells pretreated with Rp-cAMP, GLP-I failed to augment IBa. These results suggest that in pancreatic beta-cells, GLP-I, by a cAMP-dependent mechanism, increases opening of L-type Ca2+ channels. cAMP-dependent augmentation of Ca2+ entry as well as cAMP production itself by GLP-I plays a crucial role in controlling insulin secretion.

[Chondrosarcoma of the chest wall].

We report 2 patients with chondrosarcoma of the chest wall. They were a 67-year-old woman (case 1) with an anterior chest wall tumor and a 68-year-old woman (case 2) with a painful rib tumor. Their computed tomography (CT) both revealed calcified tumors. Case 1 underwent a wide resection by partial sternectomy, with free surgical margins. Case 2 underwent tumor resection with the posterior part of the 3rd rib, with positive surgical margin in the vertebral site, and received adjuvant radiotherapy. Both patients were pathologically diagnosed as having grade II chondrosarcoma. In their postoperative courses, they are free from recurrence. Wide resection is likely to be the key to successful management of chest wall chondrosarcoma.

Overexpression of cdk4/cyclin D1 induces apoptosis in PC12 cells in the presence of trophic support.

The induction of apoptosis by cell cycle regulator molecules under conditions optimal for exponential growth was examined in rat pheochromocytoma PC12 cells by overexpression of cyclins and cyclin-dependent kinases (cdks). By flow cytometry and by immunofluorescence, only cells overexpressing cdk4 or cyclin D1 underwent apoptosis, which was not associated with G1-arrest. Cdk4 kinase activity was significantly higher in cdk4-, or cyclin D1-expressing cells. Furthermore, induction of apoptosis by cdk4 was abrogated by co-transfection of p16(INK4), or dominant negative cdk4. These results suggest that upregulation of cdk4 kinase activity is a primary and critical mediator of apoptosis in PC12 cells under physiological conditions.

Overexpression of p53 as a possible prognostic factor in human thyroid carcinoma.

A total of 110 cases of thyroid carcinomas were examined immunohistochemically to evaluate the overexpression of mutant forms of p53 protein in the light of their relationship with their histological subtypes. A polyclonal antibody, CM-1, was applied to the routine formalin-fixed, paraffin-embedded tissues for this survey. Overall, immunohistochemically detected p53 expression confined to the nucleus was identified in 22.7% of the thyroid carcinomas. A significant difference in the positivity of p53 among histological subtypes was noted; the positivity was 11.1% of the cases in well-differentiated papillary carcinoma, 14.3% in well-differentiated follicular carcinoma, 40.9% in poorly differentiated carcinoma, and 63.6% in undifferentiated carcinoma. No immunohistochemical positivity was found in adjacent non-neoplastic tissues or in benign lesions, including follicular adenoma, adenomatous goiter, and chronic thyroiditis. These results suggest that overexpression of p53 is not a responsible factor for the oncogenesis itself, but rather that it plays a crucial role in aggressive subtypes of thyroid carcinomas. Additionally, the distinct entity of poorly differentiated carcinoma, previously categorized in the well-differentiated carcinoma under the name of papillary or follicular carcinoma, was statistically confirmed.

Large cell neuroendocrine carcinoma of the lung: a histologic and immunohistochemical study of 22 cases.

Large cell neuroendocrine carcinoma (LCNEC) of the lung is defined as a poorly differentiated and high-grade neuroendocrine tumor that is morphologically and biologically between atypical carcinoid and small cell lung carcinoma (SCLC). During a survey concerning bcl-2 protein expression in the subtypes of lung cancer, we noticed that two previously diagnosed non-SCLCs met the criteria for LCNEC. Because LCNEC is a newly recognized clinicopathologic entity and because all reported cases have been retrieved from the so-called "neuroendocrine tumor file," we suspected that LCNEC had been underdiagnosed. In the present study, we histologically reviewed 766 surgically resected lung cancers and were able to diagnose 22 (2.87%) LCNECs with the neuroendocrine features subsequently confirmed by immunostaining for multiple neuroendocrine markers. Each case stained positively for at least three general neuroendocrine markers, and 12 (54.5%) also were positive for neuroendocrine hormones. Histologically, most LCNECs showed a marked decrease in or a loss of organoid architecture and could be mistaken for poorly differentiated adenocarcinoma or squamous cell carcinoma. Because our LCNECs are the first to be identified by retrospective review of routinely diagnosed lung cancers, and 18 had been classified as non-SCLC, they may represent cases relatively difficult to diagnose. The present study shows that the most difficult diagnostic factor of LCNEC is the recognition of its light microscopic neuroendocrine features, and LCNEC must be distinguished not only from atypical carcinoid or SCLC, but also from common non-SCLC. Histologically, when an organoid architecture is subtle or absent, the rosettelike structure becomes the best marker for the recognition of neuroendocrine differentiation. Clinically, the prognosis for our LCNECs was significantly worse than that for stage-comparable non-SCLCs (p = 0.046).

Alteration of immunoreactivity by hydrated autoclaving, microwave treatment, and simple heating of paraffin-embedded tissue sections.

The effects of treatment in a hydrated autoclave (121 degrees C, 2 atm for 20 min), microwave oven (in water), and simple heating (60 degrees C overnight in distilled water or 90 degrees C for 10 min in ZnSO4) on the stainability of 56 antigens by commercially available antibodies in formalin-fixed paraffin-embedded tissue sections were evaluated. The detectability of nuclear antigens, glycoprotein, lymphocytic surface markers, and chromogranin A was significantly and reproducibly improved by these treatments, whereas the detectability of viral antigens and peptide hormones was attenuated or unchanged. This enhancement includes not only the distinctiveness of the positive staining, but also the number of positive cells, as revealed by comparing serial sections. Among these four heating procedures, microwave heating and autoclaving were more effective than the others on p53, c-erbB-2, and CA125, whereas simple heating was best for smooth-muscle actin (HHF35 and CGA7). Generally the effects of the heating procedures for these antigens were consistent among the cases, but the effects on GFAP varied with the case. The alterations we observed could significantly influence the interpretation of immunohistochemical staining of currently popular tumor markers such as p53 in terms of their prevalence (28% vs 64% in gastric cancer; 36% vs 82% in metastatic liver cancer) and other diagnostically important markers.

Stepwise participation of p53 gene mutation during dedifferentiation of human thyroid carcinomas.

The spectrum of p53 gene mutations was investigated in thyroid carcinomas with respect to histopathological classification. In all histological subtypes of thyroid carcinoma that had previously revealed positivity in immunohistochemical staining for p53 protein, single-stranded conformation polymorphism analysis and direct sequencing were performed to detect point mutations between exons 5 and 8. In well differentiated papillary and follicular carcinomas, in which we had already known that 11.1 and 14.3% of the cases, respectively, revealed p53 overexpression as determined by immunohistochemistry, genetic aberrations were undetectable. In poorly differentiated carcinoma, in which 40.9% had revealed overexpression, two of six cases revealed point mutations at codon 244 in exon 7 and at codon 278 in exon 8. In undifferentiated carcinoma, in which 63.6% had revealed overexpression, four of six cases examined showed point mutations at codon 157 in exon 5, at codon 248 in exon 7, and at codon 273 and a two-base insertion between codons 266 and 267 in exon 8. These results strongly suggest the crucial role of p53 gene aberration and protein overexpression in a biologically aggressive subtype, possibly as a stepwise participation in the process of tumor dedifferentiation in human thyroid carcinomas.

Possible association of p53 overexpression and mutation with high-grade chondrosarcoma.

Overexpression and point mutation of the p53 protein/gene was investigated in a series of chondrosarcoma by an immunohistochemical approach, and direct sequencing of the genomic DNA, respectively. In 2 of the 16 cases studied, both of which were high grade chondrosarcomas (grade III), immunodetectable p53 was identified. Histologically, one was ordinary type and the other a clear cell variant. However, no positivity was observed in the other cases including nine of low grade, ordinary type, three of low grade, clear cell type, and two of extraskeletal myxoid chondrosarcoma. Direct sequencing, following polymerase chain reaction amplification of exons 5-9 of the p53 gene in 14 cases, in which fresh materials were available, successfully demonstrated base substitution mutations in only two cases with detectable p53 overexpression on immunohistochemistry. Their details were GTC (valine) to TTC (phenylalanine) at codon 157 in exon 5, and CGT (arginine) to CAT (histidine) at codon 273 in exon 8. No mutation was detected in the other 12 cases which were negative for p53 immunostaining. These findings strongly suggest that p53 mutation plays a crucial role in the biologically aggressive subtype, and possibly in the process of tumor progression in human chondrosarcoma.

Hepatic resection under the intermittent selective portal branch occlusion by balloon catheter.

BACKGROUND: In hepatic resection, it is important to control intrahepatic blood flow to minimize blood loss. Intermittent and selective vascular occlusion, if possible, are advisable. STUDY DESIGN: For this purpose, we created the double balloon catheter, which when introduced into a lobar or a smaller branch of the intrahepatic portal vein through a branch of the ileocolic vein, made it possible to occlude these branches temporarily during hepatic resection. The small balloon located at the tip of the catheter made it easy to introduce the catheter to the portal branch selectively, under the guidance of ultrasonography. Another balloon was inflated intermittently to occlude selective portal blood flow. Using this technique, hepatic resection was achieved in 18 consecutive patients: 13 with hepatocellular carcinomas (11 with cirrhosis, two with chronic hepatitis), one with cholangiocellular carcinoma, three with metastatic carcinomas, and one with intrahepatic calculi. RESULTS: In these cases, 19 hepatic resections were performed; two left hepatectomies, one extended right hepatectomy, one right hepatectomy, six segmentectomies, eight subsegmentectomies, and one partial hepatectomy. In each case, well demarcated hepatic tissue delineated by ischemic change was removed with minimal bleeding and little impairment to the residual hepatic tissue, resulting in a good postoperative course. CONCLUSIONS: This double balloon catheter can replace the dissection of the hepatoduodenal ligament for hepatic resection, which causes bleeding, especially in patients with cirrhosis, and results in less cell injury of the residual hepatic parenchyma.

Giant epiphrenic diverticulum with achalasia occurring 20 years after Heller's operation.

We report a case of giant epiphrenic diverticulum in a 43-year-old woman who underwent Heller's myotomy because of achalasia 20 years earlier. She complained of heartburn and dysphagia from March of 1991 and was hospitalized in our institution. An upper gastrointestinal X-ray examination with contrast medium revealed a large hemispheric lesion (7.8 x 4.8 cm) occupying the right posterior wall of the lower thoracic and abdominal esophagus. Manometry revealed a motility disorder and high pressure of the lower esophageal sphincter due to achalasia. Therefore she was diagnosed as having a giant diverticulum with achalasia after Heller's operation. She underwent transhiatal esophagectomy and reconstruction with placement of a gastric tube on June 4, 1992. Pathology results on the resected specimen revealed a false diverticulum. She has been doing well for 4 years since the operation. It has been said that a complication of incomplete long myotomy causes pulsion diverticulum, but we could not find a case of epiphrenic diverticulum after myotomy for achalasia reported in the literature in the last 10 years.

Infrequent somatic mutations of the p16 and p15 genes in human bladder cancer: p16 mutations occur only in low-grade and superficial bladder cancers.

A recently identified gene, p16, located on chromosome 9p21, has been shown to be deleted and/or mutated in various types of human cancers. To investigate structural alterations of p16 and a neighboring gene, p15, we examined human bladder cancers for mutations in the entire coding region of these genes using polymerase chain reaction and single-strand conformational polymorphism analysis. Of 50 samples obtained from patients with bladder cancer, 3 (6%), all low-grade and superficial tumors, were found to have p16 gene alterations. The alterations included 1 missense mutation and 2 single-base deletions. We found no p15 gene mutations in these 50 bladder cancers. Our results suggested that p16 gene mutations, although they occurred at low frequency, are involved in some low-grade and early stage bladder cancers.

Neck and abdominal muscle activity during a sniff.

Measurement of sniff nasal inspiratory pressure (SNIP) is now used widely as a simple, non-invasive assessment of global respiratory muscle strength, even though the technique evolved originally from measurements of trans-diaphragmatic pressure (Pdi) that reflect the status of the diaphragm. The relative participation of major respiratory muscles, apart from the diaphragm, in the generation of SNIP is not known. Therefore, we examined the activity during a sniff of both neck and abdominal "accessory" muscles. In seven young adults we implanted fine wire EMG electrodes under direct vision with high-resolution ultrasound into scalene, sternocleidomastoid, trapezius, and transversus abdominis. SNIP was measured during sniffs that were short and sharp, from low to maximal intensity, in both standing and supine postures. Mean maximum SNIP was -105.6cmH2O (SD 32.9) in supine and -94.5cmH2O (26.6) in the standing posture, (difference NS). In every subject, scalene activity appeared even at the lowest SNIP, and increased linearly with increasing SNIP. Sternomastoid activity appeared at higher SNIP levels in three of seven subjects. By contrast, trapezius activity was never present at low SNIP, and appeared in only 2 subjects at maximum SNIP. Sniff abdominal expiratory activity was inconsistent with no activity of transversus in four of seven subjects even at greatest SNIP. Thus, we observed differential activation among these non-diaphragm respiratory muscles during SNIP; while some accessory muscles were very active, others were unlikely to contribute to generation of SNIP. Clinically, this indicates SNIP will be impacted unequally by loss of function of specific respiratory muscles.

Portal hypertension: influence on management.

In treating cases of portal hypertension, it is important to know the intramural, extramural, and communicating vascular structures of the esophagus and stomach using EUS. From these structures, suitable treatment for the esophagogastric varices can be selected and the efficacy of treatment can be evaluated.

Hyalinizing spindle cell tumor with giant rosettes: report of a case showing remarkable myofibroblastic differentiation.

We examined the proliferative activity and the differentiation line of tumor cells in a case of "hyalinizing spindle cell tumor with giant rosettes" (HSCGR). A 6 cm tumor within the right deltoid muscle of a 58-year-old female was found by physical and radiographical examinations. A biopsy revealed the histological features of a spindle cell tumor with rosette-like structures. Wide excision was done under the diagnosis of HSCGR. The tumor presented as a gray-whitish, solid mass with focal pseudocystic degeneration. Immunohistochemically, the tumor cells were diffusely positive for vimentin and were also focally positive for S-100, but negative for desmin and alpha-smooth muscle actin. The cells stained positively for Ki-67 with even distribution, there being a correlation with the cellularity of the areas, with a labeling index ranging from 0.3 to 0.5%. In addition, flow cytometry revealed an almost normal diploid DNA pattern and 5.8% S-phase fraction, indicating low proliferative activity. Ultrastructurally, many tumor cells displayed discontinuous basal lamina, pinocytotic vesicles, dilated rough endoplasmic reticulum, and microfilaments with focal dense bodies. The main component of the rosette was collagenous fibrils with normal diameter and normal periodic banding. We interpreted this case of HSCGR as a low grade fibrosarcoma with remarkable differentiation of myofibroblastic lineage, and with focally accumulated, morphologically normal collagenous fibrils.

A chondromyxoid fibroma-like tumor of the cranial convexity: immunohistochemical and ultrastructural study.

A rare chondromyxoid fibroma-like tumor arising from the temporal bone in a 49-year-old man is described. This case appears to be only the second reported of a cranial lesion of the tumor for which diagnosis could be confirmed by immunohistochemistry and electron microscopy.

Neuron-specific enolase-producing epithelioid leiomyosarcoma with gross vascular invasion and intracardiac involvement.

We present an unusual case of epithelioid leiomyosarcoma in the right shoulder. A 10-cm tumor eroding the right scapula occurred in a 59-year-old man and grew into the subclavian vein with extension to the right atrium. An elevated serum level of neuron-specific enolase was also detected. Clinical presentation suggested small cell carcinoma of the lung (Pancoast tumor) with intravenous extension. Eventually, the patient died of respiratory insufficiency. Autopsy revealed a primary tumor in the right shoulder, numerous tumor emboli in the pulmonary arteries, and associated hemorrhagic infarction. Histopathologic features revealed an epithelioid leiomyosarcoma. Furthermore, immunohistochemical and immunoblotting analyses of the tumor demonstrated positive reactions for neuron-specific enolase. We interpreted this peculiar case to be a neuron-specific enolase-producing epithelioid leiomyosarcoma of the soft tissue associated with gross vascular invasion.

Familial aggregation of soft tissue sarcomas: a report of three cases from a Li-Fraumeni-like family.

Three rare cases of familial aggregation of soft tissue sarcomas (malignant fibrous histiocytoma in a mother and liposarcomas in her two children) are described. The mother developed a late onset of malignant fibrous histiocytoma in her right thigh. Her son and daughter both developed retroperitoneal liposarcomas at the ages of 38 and 33 years, respectively. The mother also developed gastric carcinoma as a second malignancy after a 2-year interval. These clinical features closely resemble those of Li-Fraumeni syndrome, but do not fulfill the exact diagnostic criteria. Genetically, the germline mutation of the p53 gene between exons 4 and 9 was not detected by sequencing DNA obtained from the peripheral blood of the mother. Immunohistochemically, p53 protein was found only in the liposarcoma of the daughter. These results strongly suggest that this familial aggregation of soft tissue sarcomas is very rare, and that it is a unique feature of a familial cancer syndrome that to our knowledge has not been defined or described previously.