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D C Miller

Publications and source records attributed to D C Miller.

At least 217 records · Page 12Linked to original sources
PubMed1991

Regional epicardial and endocardial two-dimensional finite deformations in canine left ventricle.

We evaluated subepicardial and subendocardial two-dimensional finite deformations in the left ventricular (LV) anterior, lateral, and posterior regions in the closed-chest, conscious dog heart. Eight dogs underwent placement of 22 radiopaque markers in the LV myocardium. Sets of three markers were implanted in the anterior, lateral, and posterior subepicardium and subendocardium at the mid-ventricular level; reference markers were placed at apical and basal sites. Eight hours later, biplane videofluoroscopy was performed. Finite deformations for each subepicardial and subendocardial region were analyzed during three consecutive beats at end expiration. Circumferential shortening occurred in all layers and regions; similarly, longitudinal shortening occurred in all layers except that of the posterior endocardium. Values of principal strain were -0.19 +/- 0.08 (SD) and -0.10 +/- 0.03 for the anterior subendocardium and subepicardium, -0.20 +/- 0.07 and -0.10 +/- 0.02 for the lateral subendocardium and subepicardium, and -0.13 +/- 0.02 and -0.10 +/- 0.03 for the posterior subendocardium and subepicardium respectively (P less than 0.05 subendocardium vs. subepicardium). Second principal strain tended to be near zero or positive (from -0.01 +/- 0.05 to 0.04 +/- 0.05) in all regions. The end-systolic direction of principal strain was -29 +/- 32 degrees and -34 +/- 29 degrees in the anterior subepicardium and subendocardium, -47 +/- 10 degrees and -30 +/- 37 degrees in the lateral subepicardium and subendocardium, and -4 +/- 29 degrees and +7 +/- 23 degrees in the posterior subepicardium and subendocardium. Anterior and lateral directions of principal strain were similar in the subepicardial and subendocardial layers and oriented along the epicardial fiber axis, but the posterior direction tended to be circumferentially oriented.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

Alterations in left ventricular diastolic twist mechanics during acute human cardiac allograft rejection.

BACKGROUND: Contraction of obliquely oriented left ventricular (LV) fibers results in a twisting motion of the left ventricle. The purpose of this study was to assess the effects of acute human cardiac allograft rejection on LV twist pattern and the twist-volume relation. METHODS AND RESULTS: Tantalum markers were implanted into the LV midwall in 15 transplant recipients to measure time-varying, three-dimensional chamber twist using computer-assisted analysis of biplane cinefluoroscopic images. Twist was defined as the mean longitudinal gradient of circumferential rotation about the LV long axis. When plotted against normalized percent ejection fraction (%EF), the resulting twist-normalized %EF relation could be divided into three phases. In systole, LV twist was linearly related to ejection of blood. In contrast, diastolic untwist was characterized by early rapid recoil with little change in LV volume, followed by more gradual untwisting when the bulk of diastolic filling occurred. During 10 acute rejection episodes in 10 patients, maximum twist, peak systolic twist rate, and the slope of the systolic twist-normalized %EF relation did not change. In contrast, the slope of the early (first 15% of filling) diastolic twist-normalized %EF relation (M(early-dia)) decreased significantly (-0.194 +/- 0.062 [prerejection] versus -0.103 +/- 0.054 rad/cm [rejection], p = 0.0003), resulting in a prolonged tau 1/2 (time required to untwist by 50% [20 +/- 5% versus 28 +/- 5% of diastole], p = 0.0003) and decrease in percent untwisting at 15% diastolic LV filling (62 +/- 11% versus 36 +/- 13%, p = 0.0003). Therefore, a greater proportion of LV untwisting occurred later in diastole during rejection, as reflected by an increase in the slope (M(mid-dia)) of the middle to late (from 15 to 90% filling) diastolic twist-normalized %EF relation (-0.018 +/- 0.009 versus -0.030 +/- 0.010 rad/cm, p = 0.0015). Peak rate of untwist was not affected. With resolution of rejection, M(early-dia) and percent untwist during early diastole returned to baseline levels (p = NS versus baseline). There was also a trend for M(mid-dia) to return toward prerejection values (p = NS versus baseline), but this change did not reach statistical significance compared with rejection values. CONCLUSION: Acute cardiac allograft rejection is associated with altered diastolic twist mechanics in the absence of any demonstratable systolic abnormalities. During rejection, myocardial edema and other factors may result in intrinsic changes of the elastic properties of the myocardium, thereby leading to modification of recoil forces responsible for the early, rapid unwinding of the deformed ventricle.

Acute Disease↗
PubMed1991

Effect of volume loading, pressure loading, and inotropic stimulation on left ventricular torsion in humans.

BACKGROUND: The transmural distribution of fiber angles and the extent of shortening among obliquely oriented fibers are likely to be major determinants of the twisting motion that accompanies left ventricular (LV) ejection. As such, measurements of torsion may provide useful information about LV contractile function, but other factors, such as ventricular loading conditions, may also regulate this motion. METHODS AND RESULTS: Torsion angles (theta i) of midventricular and apical regions were measured relative to a reference minor axis near the base in seven human cardiac allografts from biplane radiographic images of metallic midwall markers. Pressure loading with methoxamine (5-10 muk/kg/min) increased LV end-systolic pressure by 41 +/- 14 mm Hg (p less than 0.0001). Volume loading with normal saline raised LV end-diastolic pressure from 9.9 +/- 5.2 to 19.6 +/- 4.9 mm Hg (p less than 0.0001). These alterations in LV loading conditions were associated with no change in theta i (difference not significant) for any marker site. Inotropic stimulation with dobutamine (5 micrograms/kg/min) increased values of theta i by as much as twofold (p less than 0.05); this response varied considerably depending on marker location, with the middle and apical inferior wall and the apical lateral wall being the most sensitive. When the marker site associated with the largest torsion angle (theta max) was considered in each patient, dobutamine increased theta max in all cases (25.2 +/- 10.5 degrees versus 15.8 +/- 7.7 degrees, p less than 0.001), whereas pressure and volume loading had negligible effects. This 59% increase in theta max was greater than that of conventional load-dependent indexes of LV systolic performance such as stroke volume (16%), ejection fraction (22%), and maximum rate of LV pressure rise (52%). CONCLUSIONS: This component of LV motion is relatively insensitive to alterations in preload and afterload, while changes in contractile state influence LV torsion in a regionally heterogeneous manner. Quantification of LV torsion may, therefore, provide a sensitive and relatively load-independent measure of contractile performance that may prove to be useful in the serial assessment of LV function.

Cineradiography↗
PubMed1991

Importance of mitral subvalvular apparatus in terms of cardiac energetics and systolic mechanics in the ejecting canine heart.

To assess the importance of the intact mitral subvalvular apparatus for left ventricular (LV) energetics, data from nine open-chest ejecting canine hearts were analyzed using piezoelectric crystals to measure LV volume. After mitral valve replacement with preservation of all chordae tendineae, baseline LV function was assessed during transient caval occlusion: A quadratic fit of the LV end-systolic pressure-volume data was used to determine the curvilinear end-systolic pressure-volume relationship (ESPVR). All chordae were then divided with exteriorized snares. Reassessment revealed deterioration of global LV pump function: (a) the coefficient of nonlinearity, decreased (less negative) by 90% (P = 0.06); (b) slope of the curvilinear ESPVR at the volume axis intercept, decreased by 75% (P = 0.01); and V100, end-systolic volume at 100 mmHg end-systolic pressure, increased by 42% (P less than 0.02). Similarly, preload recruitable stroke work fell significantly (-14%) and Vw1,000 (end-diastolic volume [EDV] at stroke work [SW] of 1,000 mmHg.ml) rose by 17% (P less than 0.04). With respect to LV energetics, the total mechanical energy generated by the ventricle decreased, as indicated by a decline in the slope of the pressure volume area (PVA)-EDV relationship (120 +/- 13 [mean +/- SD] vs. 105 +/- 13 mmHg, P less than 0.001). Additionally, comparison of LV SW and PVA from single beats with matched EDV showed that the efficiency of converting mechanical energy to external work (SW/PVA) declined by 14% (0.65 +/- 0.13 vs. 0.56 +/- 0.08, P less than 0.03) after chordal division. While effective systemic arterial elastance, Ea, also fell significantly (P = 0.03) after the chordae were severed, the Ea/Ees ratio (Ees = slope of the linear ESPVR) increased by 124% (0.91 +/- 0.53 vs. 2.04 +/- 0.87, P = 0.001) due to a proportionally greater decline in Ees. This indicates a mismatch in ventriculo-arterial interaction, deviating from that required for maximal external output (viz., Ea/Ees = 1). These adverse effects of chordal division may be related to the observed changes in LV geometry (i.e., eccentricity). We conclude that the intact mitral subvalvular apparatus is important in optimizing LV energetics and ventriculo-vascular coupling in addition to the enhancement of LV systolic performance.

Animals↗
PubMed1991

Brain and spinal cord hemorrhage in long-term survivors of malignant pediatric brain tumors: a possible late effect of therapy.

Three children with malignant primary CNS tumors treated with craniospinal radiotherapy developed intraparenchymal hemorrhages a median of 5 years following therapy in sites distant from the primary tumor. Radical surgical procedures disclosed fresh and old hematoma, gliosis, and necrosis in all 3 patients and an aggregation of abnormal microscopic blood vessels in two. No tumor was found. All 3 patients remain in long-term (greater than 10 years) continuous remission.

Adolescent↗
PubMed1991

Effect of active immunization against growth hormone-releasing factor on growth and onset of puberty in beef heifers.

Angus and Charolais heifers (195 +/- 7 kg) were actively immunized against growth hormone-releasing factor (GRF) to evaluate the effect on concentrations of somatotropin (ST), insulin-like growth factor I (IGF-I), insulin (INS), growth, and onset of puberty. Primary immunizations were given at 184 +/- 7 d of age (d 0 of experiment) by injecting (s.c.) 1.5 mg of GRF-(1-29)-Gly-Gly-Cys-NH2 conjugated to 1.5 mg of human serum albumin (GRFi, n = 22) or 1.5 mg of human serum albumin (HSAi, n = 21). Booster immunizations of .5 mg of antigen were given on d 62, 92, 153, and 251. Antibody binding (percentage at 1:2,000 dilution) to [125I]GRF on d 69 was greater (P less than .01) in GRFi (53.7 +/- 4.5) than in HSAi (10.1 +/- .6) heifers. Serum concentration (ng/ml) and frequency (peaks/5 h) of ST release, respectively, on d 78 were lower (P less than .01) in GRFi than in HSAi heifers (3.3 +/- .1 vs 5.6 +/- .2 and .9 +/- .3 vs 2.3 +/- .2). Serum IGF-I (ng/ml) was lower (P less than .01) in GRFi than in HSAi heifers on d 69 (41 +/- 5 vs 112 +/- 4). Serum INS (microU/ml) on d 78 was lower (P less than .05) in GRFi (2.2 +/- .1) than in HSAi (3.8 +/- .2) heifers. Feed intake, ADG, and feed efficiency were lower (P less than .05) in GRFi than in HSAi heifers. Hip height was lower (P less than .01) and fat thickness was greater (P less than .05) in GRFi than in HSAi heifers by d 132 and 167, respectively. Percentage of heifers attaining puberty (progesterone greater than 1 ng/ml for two consecutive weeks) by d 209 and 379 (12.9 and 18.5 mo of age), respectively, was lower (P less than .05) in GRFi (40.9 and 45.5) than in HSAi (81.0 and 100). In conclusion, growing heifers were successively immunized against GRF. Active immunization against GRF resulted in decreased serum concentration of ST, IGF-I, and INS. In addition, GRF immunization led to lowered feed intake, ADG, and feed efficiency, increased fat depth, and delayed onset of puberty in heifers. We propose that ST and IGF-I are important metabolic mediators involved in the initiation of puberty in heifers.

Animals↗
PubMed1991

Aortic dissection resulting from tear of transverse arch: is concomitant arch repair warranted?

Forty-seven patients with aortic dissection resulting from a primary tear located in the transverse aortic arch underwent surgical treatment. Twenty-six patients had acute type A, 7 had acute type B, 7 had chronic type A, and 7 had chronic type B aortic dissections. Of the 33 patients with acute dissections, 11 (7 acute type A and 4 acute type B) underwent concomitant arch repair with an operative (less than or equal to 30 days) mortality rate of 55% (35% to 73%, +/- 1 asymmetric 70% confidence limit) (2 of 7 acute type A and 4 of 4 acute type B). Concomitant arch repair was omitted in 22 patients with acute dissections (19 acute type A and 3 acute type B); the operative mortality rate was 41% (29% to 54%) (7 of 19 acute type A and 2 of 3 acute type B) (p = not significant versus arch repair). The overall survival rate for those with arch repair was 45% +/- 15% (+/- 1 standard error of the estimate) at 4 years, compared with 43% +/- 11% for patients without arch repair (p = not significant). Considering the type of dissection, the 4-year survival estimate for patients with acute type A dissections who underwent arch repair (5 hemiarch and 2 total arch) was 71% +/- 17% (versus 44% +/- 12% for acute type A patients without arch repair). There were no survivors among the 4 patients with acute type B dissections who had an arch repair (1 hemiarch and 3 total arch), whereas patients with acute type B dissections who did not undergo concomitant arch repair had a 4-year survival estimate of 33% +/- 27% (p = not significant versus arch repair). Four other patients with acute type B dissections resulting from an arch tear were managed medically and tended to have a slightly better prognosis (2-year survival estimate of 75% +/- 22% versus 14% +/- 13% for all surgically treated acute type B patients), but again this difference was not statistically significant. Multivariate analysis of the 47 surgical patients revealed that advanced age (p = 0.0008), preoperative dissection complications (p = 0.02), and other coexistent medical problems (p = 0.03) were the only significant, independent determinants of overall mortality. Initial arch repair was not a significant predictor. Nine percent (2/22) of patients with acute type A dissections who initially underwent isolated ascending aortic replacement required subsequent arch replacement; 1 died after reoperation.(ABSTRACT TRUNCATED AT 400 WORDS)

Actuarial Analysis↗
PubMed1991

Glioneurofibroma: renaming the pediatric "gliofibroma": a neoplasm composed of Schwann cells and astrocytes.

Three children had central nervous system tumors with histologic and ultrastructural features corresponding to those of tumors previously described as "gliofibromas." These features, which include a composite appearance with glial and mesenchymal elements, with glial fibrillary acidic protein (GFAP)-containing and GFAP-immunonegative cells, diffuse S-100 immunoreactivity, and basal lamina wrapping processes of both cell types, suggest that the "mesenchymal" cells are Schwann cells, not fibroblasts. We therefore propose to rename this entity "glioneurofibroma." The clinical behavior of these lesions is uncertain but is more often indolent or benign.

Astrocytes↗
PubMed1991

Freehand allograft aortic valve replacement and aortic root replacement. Utility of intraoperative echocardiography and Doppler color flow mapping.

UNLABELLED: Seventeen consecutive patients undergoing 20 planned aortic valve replacements with allograft valves at Stanford University Medical Center were studied with intraoperative epicardial echocardiography and Doppler color flow mapping before and after cardiopulmonary bypass. Native aortic valves were replaced in 12 of the 20 patients, and eight patients underwent second aortic valve procedures. In 17 of 20 patients allograft selection was guided by prebypass echocardiographic estimates of annular diameter and/or length of allograft aortic root required. Other prebypass findings included unanticipated severe mitral regurgitation in one patient (which precluded allograft aortic valve replacement), left-to-right shunts in five patients, ascending aortic dissection in one, and aortic root disease necessitating coronary reimplantation or bypass in two. Postbypass echocardiography demonstrated acceptable competency of 18 of 19 allograft valves (mild or no aortic insufficiency). Postbypass echocardiography also documented successful repair of four of five shunts and mild mitral regurgitation in 15 of 19 patients (versus 11 of 19 before bypass). CONCLUSIONS: Intraoperative echocardiography-Doppler mapping is a useful adjunct for allograft aortic valve or aortic root replacement; it allows confident selection of appropriate tissue size before aortic cross clamping, which minimizes delay from allograft thawing procedures. It also provides helpful information about the extent of aortic root disease and coronary ostial anatomy before bypass, confirms allograft competency after bypass, and detects accompanying valvular and other hemodynamic lesions before and after allograft valve replacement.

Adult↗
PubMed1991

Mitral valve repair versus replacement.

When considering all the major series comparing the early and late results of mitral valve repair versus prosthetic or bioprosthetic mitral valve replacement, the operative mortality rate is slightly lower for patients undergoing valve reconstruction. Late survival is also superior after valve repair. Although these modest differences may be related to patient selection bias, a lower rate of thromboembolic and endocarditis-related complications and improved LV function remain as rather compelling factors favoring valve repair. The durability of valve repair is comparable to valve replacement in terms of reoperation rate, except in cases of rheumatic valve abnormality (in which reoperation rates are higher after valvuloplasty). Definitive, objective evidence favoring mitral valve repair is lacking given the short period of followup in all studies and absence of controlled, randomized clinical trials. The success of mitral valve reconstruction relies heavily on the experience and technical expertise of the surgeon. The wide variability in observed survival rates, however, is unlikely to be due to differences in surgical skill between experienced groups; it more likely represents the results of differing criteria for mitral valve repair, various followup intervals, and comparisons between distinctly different cohorts. Although a prospective randomized trial would be ideal to compare the results of mitral valve reconstruction versus mitral valve replacement for patients with mitral valve regurgitation, it is unlikely and unrealistic that such a study will ever be conducted. The universal applicability of the results of such a study would also be dubious, given the widely varying extent of surgical expertise with mitral valve repair. Furthermore, not all types of mitral regurgitation are amendable to reconstruction short of using patch techniques (usually autologous pericardium treated with glutaraldehyde) or resorting to artificial chordae (e.g., extensive leaflet destruction from rheumatic changes or infective endocarditis, and substantial anterior leaflet redundancy). In cases in which mitral valve replacement is necessary, preservation of the mitral subvalvular apparatus promises to be an important concept to preserve optimal systolic LV function postoperatively.

Heart Valve Prosthesis↗
PubMed1991

Preservation of aortic valve in type A aortic dissection complicated by aortic regurgitation.

Two hundred fifty-two patients underwent operation for type A aortic dissection at Stanford University Medical Center from 1963 to 1987 and Duke University Medical Center from 1975 to 1988. Sixty-seven percent had an acute type A dissection and 33% had a chronic type A dissection. In addition to repair or replacement of the ascending aorta, 121 patients (48%) required an aortic valve procedure. Valve resuspension was performed in 46 (39 acute type A and 7 chronic type A), with an operative mortality rate of 13% +/- 5% (+/- 70% confidence limits), and aortic valve replacement in 75 (36 acute type A and 39 chronic type A), with an operative mortality rate of 20% +/- 5% (p = not significant versus resuspension). The operative mortality rate for patients requiring only repair or replacement of the ascending aorta was 32% +/- 4%. Indications for valve replacement included coexistent (nonacute) aortic valve disease, Marfan's syndrome, annuloaortic ectasia, and cases in which successful resuspension could not be accomplished. The overall actuarial survival rate for all patients was 59% +/- 3% (+/- 1 standard error of the mean), 40% +/- 4%, and 25% +/- 5% at 5, 10, and 15 years, respectively. Survival rates at these same times for patients with valve resuspension were 67% +/- 8%, 52% +/- 10%, and 26% +/- 19%, respectively; for patients who required aortic valve replacement, these survival rates were 70% +/- 5%, 39% +/- 8%, and 21% +/- 11%; finally, patients who received only an ascending aortic procedure had survival probabilities of 51% +/- 5%, 37% +/- 6%, and 23% +/- 6% (p = not significant versus resuspension versus aortic valve replacement). Multivariate analysis showed advanced age (p less than 0.001), previous cardiac or aortic operation (p less than 0.001), more preoperative dissection complications (p = 0.002), and earlier operative date (p = 0.038) to be the only significant, independent factors that increased the likelihood of early or late death. The type of aortic valve procedure (resuspension versus aortic valve replacement versus none) was not a significant predictor of mortality. Two of 46 patients with valve resuspension required late aortic valve replacement (freedom from aortic valve replacement: 100% and 80% +/- 13% at 5 and 10 years, respectively), as did 4 of 75 patients with initial aortic valve replacement (freedom from repeat aortic valve replacement: 98% +/- 2% and 73% +/- 13%, respectively).(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗
PubMed1990

Immunohistochemical localization of basic fibroblast growth factor in astrocytomas.

Because of the prominent neovascularization observed in the growth of brain tumors, we studied the occurrence of basic fibroblast growth factor (bFGF), a potent angiogenic factor in astrocytomas, the most aggressive of which often have marked vascular hyperplasia. Using immunohistochemical methods, we examined 21 examples of such tumors, 7 glioblastomas multiforme, 7 anaplastic astrocytomas, and 7 low grade astrocytomas. Using polyclonal and affinity-purified rabbit antisera to human bFGF, we detected immunoreactive bFGF in all cases of glioblastoma multiforme. bFGF was present in both endothelial cells and neoplastic astrocytes. In 4 of 7 anaplastic astrocytomas, the tumor astrocytes had bFGF immunoreactivity and, in 5 of 7 cases, endothelial cells were also immunopositive. In glioblastomas multiforme and anaplastic astrocytomas, capillaries adjacent to tumor showed bFGF immunoreactivity, whereas capillaries distant from the tumors were not immunostained. In low grade astrocytomas, astrocytic cells were weakly immunoreactive in 2 of 7 cases, and in only 1 of the 7 cases capillaries were immunostained. In each grade, reactive astroglial cells showed variable bFGF immunoreactivity. The immunostaining was not seen with the flow-through fraction obtained after affinity purification of the bFGF antiserum with pure recombinant bFGF. These results suggest a possible role for bFGF in tumor growth and in angiogenesis in astrocytomas.

Astrocytes↗
PubMed1990

A large kindred with autosomal dominant Parkinson's disease.

We report two large kindreds with Parkinson's disease (PD) apparently inherited in autosomal dominant fashion. Forty-one persons in four generations have been affected; we have examined 7 of them. The two kindreds originated in a single small town in southern Italy and therefore are probably related. The illness was typical for PD except for early onset at a mean age of 46.5 years and a rapid course that averaged 9.7 years from onset to death. Clinical appearance and response to levodopa were typical for PD. Only one instance of definite nonpenetrance is known. Autopsy of 2 patients in one kindred showed the pathological changes typical of PD with Lewy bodies. Disease duration among affected persons who spent most of their lives in Italy was longer than for their affected US relatives, suggesting that exogenous agents may influence the course of this genetic illness. We conclude that what is probably a single gene without an additional environmental insult can cause the pathological changes typical of PD. Our findings therefore enhance the likelihood of a significant genetic component in the cause of sporadic PD. By identifying a toxic gene product, future molecular genetic studies in our kindred(s) may provide insight into the pathogenesis of sporadic PD.

Adult↗
PubMed1990

Synaptophysin: a sensitive and specific marker for ganglion cells in central nervous system neoplasms.

Synaptophysin, a 38-kilodalton glycoprotein found in synaptic vesicle membranes, has been shown to be a sensitive marker of neuroendocrine differentiation in non-central nervous system (CNS) tumors. We analyzed the patterns of synaptophysin immunoreactivity in CNS neoplasms in comparison with various normal CNS sites in biopsies. Normal gray matter structures all showed a diffuse punctate granular pattern of neuropil staining without staining of neuronal cell bodies. In contrast, neoplastic ganglion cells in 18 of 18 gangliogliomas/gangliocytomas showed intense immunoreactivity outlinging the borders of the cell bodies. Focal staining was also seen in five of 16 primitive neuroectodermal tumors and in one of three central neurocytomas, but these tumors had a finely granular neuropil pattern of immunoreactivity more like that of normal gray matter than like that of the gangliogliomas. All 35 examples of pure gliomas of various types showed no immunoreactivity. Our data highlight synaptophysin as a sensitive and specific marker of both neuronal lineage and neoplastic character in gangliogliomas.

Antibodies, Monoclonal↗
PubMed1990

Synaptophysin: a sensitive and specific marker for ganglion cells in central nervous system neoplasms.

Synaptophysin, a 38-kilodalton glycoprotein found in synaptic vesicle membranes, has been shown to be a sensitive marker of neuroendocrine differentiation in non-central nervous system (CNS) tumors. We analyzed the patterns of synaptophysin immunoreactivity in CNS neoplasms in comparison with various normal CNS sites in biopsies. Normal gray matter structures all showed a diffuse punctate granular pattern of neuropil staining without staining of neuronal cell bodies. In contrast, neoplastic ganglion cells in 18 of 18 gangliogliomas/gangliocytomas showed intense immunoreactivity outlining the borders of the cell bodies. Focal staining was also seen in five of 16 primitive neuroectodermal tumors and in one of three central neurocytomas, but these tumors had a finely granular neuropil pattern of immunoreactivity more like that of normal gray matter than like that of the gangliogliomas. All 35 examples of pure gliomas of various types showed no immunoreactivity. Our data highlight synaptophysin as a sensitive and specific marker of both neuronal lineage and neoplastic character in gangliogliomas.

Biomarkers, Tumor↗