False-positive fluorine-18 fluorodeoxy-D-glucose positron emission tomography imaging caused by retained gauze in a woman with recurrent ovarian cancer: a case report

We report a case of a 47-year-old woman with a false-positive [18F]fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET) result caused by retained gauze during resection of liver metastasis for a Stage IV ovarian cancer at primary cytoreductive surgery. She achieved complete remission and remained free of progression for seven years. Owing to elevation of CA-125, computed tomography and PET studies were performed, and both showed two potentially resectable lesions. One was located ventral to the diaphragmatic surface of the left hepatic lobe and the other was around the gauze at the right hepatorenal fossa. During surgical intervention, the left supraheptic tumor was excised and the gauze with surrounding granulation was removed. However, the former proved to be recurrent ovarian cancer with the latter proven false-positive. This case demonstrates that PET results should be interpreted with caution in differentiating a benign inflammatory process from malignant abnormalities, especially in regions with a high probability of granulomatous lesions.

Liver graft-versus-host disease after donor lymphocyte infusion for relapses of hematologic malignancies post allogeneic hematopoietic stem cell transplantation

Graft-versus-host disease (GVHD) is the commonest complication after donor lymphocyte infusion (DLI). In 19 patients undergoing DLI for relapses of hematologic malignancies post hematopoietic stem cell transplantation (HSCT), 11 developed GVHD, of whom nine had isolated liver involvement, and two had liver and skin involvement. The clinical diagnosis of liver GVHD was hepatitic in six patients (55%) and classical in five patients (45%). Patients with GVHD post-DLI showed a different clinical pattern when compared to a cohort of 106 cases of GVHD post-HSCT, in having significantly more isolated liver involvement (9/11 vs 17/106, P<0.001), and less skin (2/11 vs 80/106, P<0.001) and gut (0/11 vs 28/106, P<0.001) involvement. However, liver GVHD post-DLI and post-HSCT had comparable patient characteristics, underlying diseases, clinical subtypes (classical and hepatitic) and response to treatment.

Non-myeloablative allogeneic peripheral stem cell transplantation for multiple myeloma

OBJECTIVE

To present an institution's 2-year experience of non-myeloablative allogeneic stem cell transplantation among Chinese patients.

DESIGN

Retrospective study.

SETTING

Bone marrow transplantation unit at a university hospital, Hong Kong.

PATIENTS

Ten patients with multiple myeloma who received non-myeloablative allogeneic stem cell transplantation between March 2000 and October 2002.

INTERVENTION

Fludarabine (90 mg/m(2)) and total body irradiation (300 cGy) were given as conditioning regimens, followed by non-myeloablative allogeneic stem cell transplantation.

MAIN OUTCOME MEASURES

Engraftment, regimen-related toxicity, treatment-related mortality (in the first 100 days), incidence of graft-versus-host disease, chimerism, disease response, and survival rate.

RESULTS

All 10 patients had active disease before transplantation. The donors were eight human leukocyte antigen-matched siblings, a mismatched sibling, and a matched daughter. Satisfactory engraftment before day 21 was achieved without early treatment-related mortality. Five patients developed full donor chimerism by day 28 and three other patients had 100% donor chimerism by day 100. Acute graft-versus-host disease developed in six patients (five with grade III and one with grade IV disease), and chronic graft-versus-host disease developed in eight patients (four with extensive disease). Complete remission and partial response were achieved in three and four patients, respectively. Three patients did not respond to treatment, and one case of relapse was observed. Only one patient, who had shown a partial response, received donor lymphocyte infusion; seven patients received thalidomide for graft-versus-host disease with or without graft-versus-myeloma effect. All patients were alive after a median follow-up of 1 year.

CONCLUSION

Non-myeloablative allogeneic stem cell transplantation for multiple myeloma is effective, has low toxicity, and results in low treatment-related mortality. Studies of more cases with longer follow-up durations are required.

Nontuberculous mycobacterial infections in Chinese hematopoietic stem cell transplantation recipients

Between 1995 and 2002, nine cases of nontuberculous mycobacterium (NTM) were isolated from 462 allogeneic stem cell transplant (SCT) recipients (1.9%), and none from 139 autologous cases. They included three cases each of Mycobacterium fortuitum and M. chelonae, and single cases of M. scrofalaceum, M. gordonnae and M. avium complex. Seven cases were respiratory, including five cases requiring treatment, and two involved infected catheters and vascular conduits. Compared with nine cases of mycobacterium tuberculosis (MTB) isolated in the same period, NTM isolation occurred later after HSCT and involved more unrelated donors. Important risk factors for NTM infection included significant aGVHD (P=0.043), leukemia relapse (P=0.022), MUD and mismatch SCT (P<0.001) and existence of BO (P<0.001). Coinfection with aspergillus was common. Invasive NTM disease required prolonged antimicrobial treatment in five cases due to M. fortuitum and M. chelonae. With better MTB prophylaxis, intensive immunosuppression and better awareness, NTM has become an emerging threat in oriental allogeneic HSCT recipients. The cutoff between colonization and infection, and the threshold for starting treatment is unclear. NTM isolation is a marker for severe immunosuppression and poor prognosis. When there is doubt over species identity or extent of infection, broad-spectrum cover may be prudent.

Disseminated zoster, hyponatraemia, severe abdominal pain and leukaemia relapse: recognition of a new clinical quartet after bone marrow transplantation

Reactivation of varicella-zoster virus (VZV) is one of the commonest complications after stem cell transplantation, and often presents with atypical manifestations. We describe two unusual cases of occult disseminated zoster in allogeneic stem cell transplant recipients, presenting as severe abdominal pain and syndrome of inappropriate antidiuretic hormone secretion/hyponatraemia, and accompanied by leukaemia relapse. There was complete clinical recovery with high-dose aciclovir and intravenous immunoglobulin. Prompt treatment of leukaemia relapse also resulted in complete remission. A possible immunological link between concurrent breakdown of immune control of VZV and leukaemia is discussed.

Portal hypertensive gastropathy and its interrelated factors

OBJECTIVE

To investigate the influences of helicobacter pylori (Hp) infection, liver function, gastroesophageal varicosity, esophageal varicosity ligation (EVL), and esophageal varicosity sclerotherapy (EVS) on patients with portal hypertensive gastropathy (PHG).

METHODS

Fourty-seven patients with liver cirrhosis included 34 patients with PHG and 13 patients without PHG. Liver function, Hp infection, and gastroesophageal varicosity were investigated clinically in all patients, and gastroscopy was made again in patients with EVL 1-2 months after operation to observe the changes of PHG.

RESULTS

The rate of Hp infection was lower in patients with liver cirrhosis than in controls. There was no relationship between Hp infection and PHG. The patients with gastroesophageal varicosity had a high incidence of PHG.

CONCLUSIONS

Despite no relationship between Hp infection and PHG, liver dysfunction can affect and promote PHG. Gastroesophageal varicosity may be closely related to PHG, but their degrees are not related. PHG can be caused or promoted by EVL.

A patient with congenital ichthyosis hystrix (disseminated congenital naevus) and acute lymphoblastic leukaemia

Congenital ichthyosis is an uncommon spectrum of hereditary and sporadic hyperkeratotic epidermolytic disorders that may occur in isolation or in association with other clinical syndromes. The pattern of distribution of the hyperkeratotic lesions and family history form the basis of diagnosis. Ichthyosis may be a marker for immune deficiency and cancer prone conditions. We report a 16-year old Chinese patient with a diagnosis of ichthyosis hystrix hystrix (disseminated congenital naevus) since birth who presented with T cell acute lymphoblastic leukaemia with tetraploid clones. There are four reports of acute leukaemia complicating ichthyosis, all involving paediatric acute lymphoblastic leukaemia. The possible mechanisms involved are discussed.

Unbiased morphological measurements show no neuronal loss in the substantia nigra in Alzheimer's disease

This is the first study to use the unbiased stereological method, the disector, to estimate the total number of pigmented neurons in the pars compacta of the substantia nigra (SNpc) in Alzheimer's disease (AD) patients as compared to healthy controls. The right half of the SNpc of 11 AD patients and 24 controls was studied. We also used single sections to determine the neuronal number and area in different subregions of the SNpc. The results showed that there was no significant difference in the total number of pigmented neurons in the SNpc (154,415+/-13,593 for AD and 160,163+/-8027 for controls) or in the volume of the SNpc between the patients with AD and controls. Studies on single sections revealed that even subregionally there was no significant difference in the neuronal number or area in the SNpc between AD patients and controls.

Differential role of CD18 integrins in mediating lung neutrophil sequestration and increased microvascular permeability induced by Escherichia coli in mice

The in vivo contributions of CD18 integrin-dependent and -independent mechanisms in mediating the increases in lung neutrophil (polymorphonuclear leukocyte; PMN) sequestration and microvascular permeability are not well understood. We determined the time course of these responses to Gram-negative sepsis in the mouse lung and addressed the specific contributions of CD18 integrins and ICAM-1. PMN sequestration in the lung was assessed by morphometric analysis, and transalveolar PMN migration was assessed by bronchoalveolar lavage. Lung tissue PMN number increased by 6-fold within 1 h after i.p. Escherichia coli challenge; this value peaked at 3 h (7-fold above control) and decreased at 12 h (3.5-fold above control). PMN migration into the airspace was delayed; the value peaked at 6 h and remained elevated up to 12 h. Saturating concentrations of anti-CD18 and anti-ICAM-1 mAbs reduced lung tissue PMN sequestration and migration; however, peak responses at 3 and 6 h were inhibited by 40%, indicating that only a small component of PMN sequestration and migration was CD18 dependent at these times. In contrast to the time-dependent decreased role of CD18 integrins in mediating PMN sequestration and migration, CD18 and ICAM-1 blockade prevented the increase in lung microvascular permeability and edema formation at all times after E. coli challenge. Thus, Gram-negative sepsis engages CD18/ICAM-1-independent mechanisms capable of the time-dependent amplification of lung PMN sequestration and migration. The increased pulmonary microvascular permeability induced by E. coli is solely the result of engagement of CD18 integrins even when PMN accumulation and migration responses are significantly CD18 independent.

Neuropathology of mice carrying mutant APP(swe) and/or PS1(M146L) transgenes: alterations in the p75(NTR) cholinergic basal forebrain septohippocampal pathway

Cholinergic basal forebrain (CBF) projection systems are defective in late Alzheimer's disease (AD). We examined the brains of 12-month-old singly and doubly transgenic mice overexpressing mutant amyloid precursor protein (APP(swe)) and/or presenilin-1 (PS1(M146L)) to investigate the effects of these AD-related genes on plaque and tangle pathology, astrocytic expression, and the CBF projection system. Two types of beta-amyloid (Abeta)-immunoreactive (ir) plaques were observed: type 1 were darkly stained oval and elongated deposits of Abeta, and type 2 were diffuse plaques containing amyloid fibrils. APP(swe) and PS1(M146L) mouse brains contained some type 1 plaques, while the doubly transgenic (APP(swe)/PS1(M146L)) mice displayed a greater abundance of types 1 and 2 plaques. Sections immunostained for the p75 NGF receptor (p75(NTR)) revealed circular patches scattered throughout the cortex and hippocampus of the APP(swe)/PS1(M146L) mice that contained Abeta, were innervated by p75(NTR)-ir neurites, but displayed virtually no immunopositive neurons. Tau pathology was not seen in any transgenic genotype, although a massive glial response occurred in the APP(swe)/PS1(M146L) mice associated with amyloid plaques. Stereology revealed a significant increase in p75(NTR)-ir medial septal neurons in the APP(swe) and PS1(M146L) singly transgenic mice compared to the APP(swe)/PS1(M146L) mice. No differences in size or optical density of p75(NTR)-ir neurons were observed in these three mutants. p75(NTR)-ir fibers in hippocampus and cortex were more pronounced in the APP(swe) and PS1(M146L) mice, while the APP(swe)/PS1(M146L) mice showed the least p75(NTR)-ir fiber staining. These findings suggest a neurotrophic role for mutant APP and PS1 upon cholinergic hippocampal projection neurons at 12 months of age.

Galanin transgenic mice display cognitive and neurochemical deficits characteristic of Alzheimer's disease

Galanin is a neuropeptide with multiple inhibitory actions on neurotransmission and memory. In Alzheimer's disease (AD), increased galanin-containing fibers hyperinnervate cholinergic neurons within the basal forebrain in association with a decline in cognition. We generated transgenic mice (GAL-tg) that overexpress galanin under the control of the dopamine beta-hydroxylase promoter to study the neurochemical and behavioral sequelae of a mouse model of galanin overexpression in AD. Overexpression of galanin was associated with a reduction in the number of identifiable neurons producing acetylcholine in the horizontal limb of the diagonal band. Behavioral phenotyping indicated that GAL-tgs displayed normal general health and sensory and motor abilities; however, GAL-tg mice showed selective performance deficits on the Morris spatial navigational task and the social transmission of food preference olfactory memory test. These results suggest that elevated expression of galanin contributes to the neurochemical and cognitive impairments characteristic of AD.

Loss of nucleus basalis neurons containing trkA immunoreactivity in individuals with mild cognitive impairment and early Alzheimer's disease

Recent studies indicate that there is a marked reduction in trkA-containing nucleus basalis neurons in end-stage Alzheimer's disease (AD). We used unbiased stereological counting procedures to determine whether these changes extend to individuals with mild cognitive impairment (MCI) without dementia from a cohort of people enrolled in the Religious Orders Study. Thirty people (average age 84.7 years) came to autopsy. All individuals were cognitively tested within 12 months of death (average MMSE 24.2). Clinically, 9 had no cognitive impairment (NCI), 12 were categorized with MCI, and 9 had probable AD The average number of trkA-immunoreactive neurons in persons with NCI was 196, 632 +/- 12,093 (n = 9), for those with MCI it was 106,110 +/- 14,565, and for those with AD it was 86,978 +/- 12,141. Multiple comparisons showed that both those with MCI and those with AD had significant loss in the number of trkA-containing neurons compared to those with NCI (46% decrease for MCI, 56% for AD). An analysis of variance revealed that the total number of neurons containing trkA immunoreactivity was related to diagnostic classification (P < 0.001), with a significant reduction in AD and MCI compared to NCI but without a significant difference between MCI and AD. Cell density was similarly related to diagnostic classification (P < 0.001). There was a significant correlation with the Boston Naming Test and with a global score measure of cognitive function. The number of trkA-immunoreactive neurons was not correlated with MMSE, age at death, education, apolipoprotein E allele status, gender, or Braak score. These data indicate that alterations in the number of nucleus basalis neurons containing trkA immunoreactivity occurs early and are not accelerated from the transition from MCI to mild AD.

Neurodegeneration prevented by lentiviral vector delivery of GDNF in primate models of Parkinson's disease

Lentiviral delivery of glial cell line-derived neurotrophic factor (lenti-GDNF) was tested for its trophic effects upon degenerating nigrostriatal neurons in nonhuman primate models of Parkinson's disease (PD). We injected lenti-GDNF into the striatum and substantia nigra of nonlesioned aged rhesus monkeys or young adult rhesus monkeys treated 1 week prior with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Extensive GDNF expression with anterograde and retrograde transport was seen in all animals. In aged monkeys, lenti-GDNF augmented dopaminergic function. In MPTP-treated monkeys, lenti-GDNF reversed functional deficits and completely prevented nigrostriatal degeneration. Additionally, lenti-GDNF injections to intact rhesus monkeys revealed long-term gene expression (8 months). In MPTP-treated monkeys, lenti-GDNF treatment reversed motor deficits in a hand-reach task. These data indicate that GDNF delivery using a lentiviral vector system can prevent nigrostriatal degeneration and induce regeneration in primate models of PD and might be a viable therapeutic strategy for PD patients.

Galanin regulates the postnatal survival of a subset of basal forebrain cholinergic neurons

The neuropeptide galanin colocalizes with choline acetyltransferase, the synthetic enzyme for acetylcholine, in a subset of cholinergic neurons in the basal forebrain of rodents. Chronic intracerebroventricular infusion of nerve growth factor induces a 3- to 4-fold increase in galanin gene expression in these neurons. Here we report the loss of a third of cholinergic neurons in the medial septum and vertical limb diagonal band of the basal forebrain of adult mice carrying a targeted loss-of-function mutation in the galanin gene. These deficits are associated with a 2-fold increase in the number of apoptotic cells in the forebrain at postnatal day seven. This loss is associated with marked age-dependent deficits in stimulated acetylcholine release, performance in the Morris water maze, and induction of long-term potentiation in the CA1 region of the hippocampus. These data provide unexpected evidence that galanin plays a trophic role to regulate the development and function of a subset of septohippocampal cholinergic neurons.

Pramipexole attenuates the dopaminergic cell loss induced by intraventricular 6-hydroxydopamine

The D3 preferring dopamine agonist pramipexole has been shown to attenuate the cell loss induced by levodopa in vitro. Pramipexole was herein evaluated in the 6-hydroxydopamine lesion model to determine its in vivo effect. Rats were treated with pramipexole or saline before and after an intracerebroventricular 6-hydroxydopamine injection. In the preliminary study, 6-hydroxydopamine produced a 68% reduction in striatal dopamine and a 62% loss in tyrosine hydroxylase immunoreactive (THir) cell counts in the substantia nigra. Pramipexole treated animals exhibited a 29% and a 27% reduction in striatal dopamine and THir cell counts, respectively. THir cell counts and striatal dopamine were significantly correlated. In the stereological study, 6-hydroxydopamine reduced THir cell counts by 47% in saline treated animals and 26% in pramipexole treated animals. These data demonstrate that pramipexole attenuates the biochemical and THir cell changes normally produced by 6-hydroxydopamine consistent with its neuroprotective actions in vitro.

Reduction in TrkA-immunoreactive neurons is not associated with an overexpression of galaninergic fibers within the nucleus basalis in Down's syndrome

Down's syndrome (DS) individuals develop neuropathological features similar to Alzheimer's disease (AD), including degeneration of cholinergic basal forebrain (CBF) neurons. In AD a reduction in CBF/trkA-containing neurons has been suggested to trigger a hyperexpression of galaninergic fibers within the nucleus basalis subfield of the basal forebrain. The present study examined the interrelationship between reductions in CBF/trkA-containing neurons and the overexpression of galaninergic fibers within the nucleus basalis in DS. Within the nucleus basalis stereologic evaluation revealed a 46% reduction in the number of trkA-immunopositive neurons, whereas optical density measurements displayed a nonsignificant 18% reduction in neuronal trkA immunoreactivity in DS as compared with age-matched controls. Western blot analysis also showed a significant reduction in cortical trkA protein levels in DS. A semiquantitative examination of galaninergic fibers in the nucleus basalis revealed only a modest hypertrophy of galaninergic fibers within the nucleus basalis in DS. The present findings indicate a significant reduction in trkA within the nucleus basalis and cortex with only a moderate hypertrophy of galaninergic fibers in DS. These observations suggest that DS may not be an exact genetic model for investigation of changes in the AD basal forebrain.

Lentiviral gene transfer to the nonhuman primate brain

Lentiviral vectors infect quiescent cells and allow for the delivery of genes to discrete brain regions. The present study assessed whether stable lentiviral gene transduction can be achieved in the monkey nigrostriatal system. Three young adult Rhesus monkeys received injections of a lentiviral vector encoding for the marker gene beta galatosidase (beta Gal). On one side of the brain, each monkey received multiple lentivirus injections into the caudate and putamen. On the opposite side, each animal received a single injection aimed at the substantia nigra. The first two monkeys were sacrificed 1 month postinjection, while the third monkey was sacrificed 3 months postinjection. Robust incorporation of the beta Gal gene was seen in the striatum of all three monkeys. Stereological counts revealed that 930,218; 1,192,359; and 1,501,217 cells in the striatum were beta Gal positive in monkeys 1 (n = 2) and 3 (n = 1) months later, respectively. Only the third monkey had an injection placed directly into the substantia nigra and 187,308 beta Gal-positive cells were identified in this animal. The injections induced only minor perivascular cuffing and there was no apparent inflammatory response resulting from the lentivirus injections. Double label experiments revealed that between 80 and 87% of the beta Gal-positive cells were neurons. These data indicate that robust transduction of striatal and nigral cells can occur in the nonhuman primate brain for up to 3 months. Studies are now ongoing testing the ability of lentivirus encoding for dopaminergic trophic factors to augment the nigrostriatal system in nonhuman primate models of Parkinson's disease.

Unbiased morphometrical measurements show loss of pigmented nigral neurones with ageing

This study used the dissector method to evaluate pigmented nigral neuronal loss in the substantia nigra pars compacta with age. Dissector counts can be used to estimate the absolute and accurate total neurone numbers. In addition, the area and diameter of the neuronal cell body was estimated by using a computerized morphometric analysis in a single section of the substantia nigra pars compacta. Brain samples from 26 people with an age range from 17 to 90 years were studied. A significant decrease in the total number of pigmented neurones (r=-0.83, P<0.001) and their density (r=-0.83, P<0.001) with age was found in the substantia nigra pars compacta. The number of pigmented neurones counted from a single section also showed an age-dependent decline (r=-0.76, P<0.001). According to the regression equations, the total number of pigmented neurones estimated by dissector counts decreased by 9.8% per decade and the neuronal density decreased by 7.4% per decade. The area of the neuronal cell body decreased by 3.2% per decade. This latter change corresponds to an approximate 4.4% decrease per decade in neuronal volume. These findings show that both the number of pigmented neurones and their size in the substantia nigra pars compacta decreases with age. However, the reductions in the total number of pigmented neurones are more dramatic than the reduction in neurone size with ageing.

Clinicopathological findings following intraventricular glial-derived neurotrophic factor treatment in a patient with Parkinson's disease

As part of a safety and tolerability study, a 65-year-old man with Parkinson's disease (PD) received monthly intracerebroventricular injections of glial-derived neurotrophic factor (GDNF). His parkinsonism continued to worsen following intracerebroventricular GDNF treatment. Side effects included nausea, loss of appetite, tingling, L'hermitte's sign, intermittent hallucinations, depression, and inappropriate sexual conduct. There was no evidence of significant regeneration of nigrostriatal neurons or intraparenchymal diffusion of the intracerebroventricular GDNF to relevant brain regions. Alternative GDNF delivery systems should be explored.

Dopamine transporter-immunoreactive neurons decrease with age in the human substantia nigra

Unbiased disector stereologic cell counting was applied to sections from the human substantia nigra that were immunostained by using a monoclonal antibody against the dopamine transporter (DAT). This antibody was found to penetrate the full thickness of the stained section. Quantification of the number of DAT immunostained neurons was performed in human cases stratified into three age groups, young (ages 0-49 years), middle aged (ages 50-69 years), and aged (ages 70-85 years). The number of DAT-immunoreactive nigral neurons was normalized for each case by constructing a ratio of the number of DAT-containing neurons to total number of neuromelanin-containing cells in each subject's sample. Three types of DAT nigral neurons were seen: type 1, intensely stained; type 2, lightly stained; and type 3, DAT-immunonegative neuromelanin-containing perikarya. By 50 years of age, the number of type 1 neurons decreased significantly (P < 0.0001), whereas the number of type 2 neurons increased with age (P < 0.0001). Type 3 neurons also increased with age (P < 0.01), although less robustly than type 2 neurons. Type 1 neurons decreased by 11.2% per decade, and the total number of nigral neurons (types 1-3) decreased by 6.7% per decade. Relative to the young group, there were 75% and 88% reductions in type 1 neurons in the middle-aged and aged groups, respectively. This contrasts with the 35% and 41% reductions in total number of neuromelanin-containing neurons seen in middle-aged and aged groups, respectively. The young group had significantly more type 1 neurons and fewer type 2 neurons compared with middle-aged and aged participants. Post-hoc analyses indicated that the young group had significantly fewer type 3 neurons compared with middle-aged and aged participants. These findings demonstrate an age-related reduction in the number of substantia nigra DAT-immunoreactive neurons. Therefore, insight into the mechanisms regulating the rate of DAT synthesis may aid in our understanding of the decline of DATs with aging and its functional significance.

Age-related declines in nigral neuronal function correlate with motor impairments in rhesus monkeys

Although the role of dopamine dysfunction is well established in Parkinson's disease, the effect of nigrostriatal degeneration on motor performance during normal aging is less well understood. In this study, aged rhesus monkeys (25-27 years old) displayed significant impairments relative to young (3-5 years old) cohorts in motor function as assessed on a fine motor task and home cage activity. Additionally, the clinical motor function of aged monkeys was impaired relative to young monkeys as assessed on a clinical rating scale. Unbiased stereologic measurements of the substantia nigra revealed a significant age-related loss of tyrosine hydroxylase-immunoreactive (TH-ir; 50.3%) and dopamine transporter-immunoreactive (DAT-ir; 33.2%) nigral neurons. The monkeys performance on the fine motor task and on the clinical rating scale was correlated with TH-ir neuronal counts. The number of DAT-ir nigral neurons was correlated with activity and clinical rating scale scores. Our results suggest that age-related motor impairments in nonhuman primates are associated with spontaneous decreases in TH-ir and DAT-ir nigral cells. The correlation of motor deficits with the loss of TH-ir and DAT-ir nigral neurons suggests that aged nonhuman primates may provide a useful model for mimicking changes seen in human aging and early Parkinson's disease.

Correlation between neuromorphometry in the substantia nigra and clinical features in Parkinson's disease using disector counts

Previous studies based on single sections have suggested a significant correlation between pigmented neuronal loss in the substantia nigra (SN) and clinical features in Parkinson's disease (PD). However, disector (DS) counts-unbiased and accurate stereological estimates have not been available. To evaluate total neuron numbers in the pars compacta of the substantia nigra (SNpc) in relation to clinical features, we estimated the neuron counts in the SNpc by the DS method in brain samples from 12 controls and 12 PD patients. The total number of pigmented neurons in the whole SNpc was significantly reduced in PD patients (to 45% of the control mean, P < 0.001). The density of pigmented neurons (neuron/mm3) was reduced to 51% of the average control value (P < 0.001). No significant difference was seen in the volume (mm3) of the SNpc between PD patients and controls. Furthermore, the total number of pigmented neurons in the SNpc showed a significant negative correlation with the duration of disease (r = -0.86, P < 0.001) and with the stage of disease (r = -0.58, P < 0.05) in PD patients. Using an unbiased neuron counting method, these relationships, for the first time, demonstrate that the more severe pigmented neuronal loss in the SNpc is associated with the longer duration and the more severe stage of disease in PD patients.