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Fluorinert (perfluorocarbon) represents an inexpensive option for minimizing susceptibility artifacts in ex vivo brain MRI scanning, and provides an alternative to Fomblin. However, its impact on fixed tissue and histological analysis has not been rigorously and quantitatively validated. In this study, we excised tissue blocks from 2 brain regions (frontal pole and cerebellum) of 5 formalin-fixed specimens (2 progressive supranuclear palsy cases, 3 controls). We excised 2 blocks per region per case (20 blocks in total), one of which was subsequently immersed in Fluorinert for a week and then returned to a container with formalin. The other block from each region was kept in formalin for use as control. The tissue blocks were then sectioned and histological analysis was performed on each, including routine stains and immunohistochemistry. Visual inspection of the stained histological sections by an experienced neuropathologist through the microscope did not reveal any discernible differences between any of the samples. Moreover, quantitative analysis based on automated image patch classification showed that the samples were almost indistinguishable for a state-of-the-art classifier based on a deep convolutional neural network. The results showed that Fluorinert has no effect on subsequent histological analysis of the tissue even after a long (1 week) period of immersion, which is sufficient for even the lengthiest scanning protocols.

Multiple system atrophy (MSA) is an adult-onset neurodegenerative disease characterized by aggregation of α-synuclein in oligodendrocytes to form glial cytoplasmic inclusions. According to the distribution of neurodegeneration, MSA is subtyped as striatonigral degeneration (SND), olivopontocerebellar atrophy (OPCA), or as combination of these 2 (mixed MSA). In the current study, we aimed to investigate regional microglial populations and gene expression in the 3 different MSA subtypes. Microscopy with microglial marker Iba-1 combined with either proinflammatory marker CD68 or anti-inflammatory marker Arginase-1 was analyzed in control, SND, and OPCA cases (n = 5) using paraffin embedded sections. Western immunoblotting and cytokine array were used to determine protein expression in MSA and control brain regions. Gene expression was investigated using the NanoString nCounter Human Inflammation panel v2 mRNA Expression Assay. Analysis of neuropathological subtypes of MSA demonstrated a significant increase in microglia in the substantia nigra of OPCA cases. There was no difference in the microglial activation state in any region. Cytokine expression in MSA was comparable with controls. Decreased expression of CX3CL1 precursor protein and significantly greater CX3CR1 protein was found in MSA. NanoString analysis revealed the >2-fold greater expression of ARG1, MASP1, NOX4, PTGDR2, and C6 in MSA.

Clinical syndromes associated with progressive supranuclear palsy-tau pathology now include progressive supranuclear palsy-parkinsonism (PSP-P), in addition to classic Richardson's syndrome (RS) and pure akinesia with gait freezing (PAGF). Although pathological heterogeneity of progressive supranuclear palsy (PSP) has also been established, attempts to correlate this with clinical findings have only rarely provided conclusive results. The aim of this study was to investigate whether regional variations in the types of tau lesions or differences in overall tau load may explain the clinical differences between the RS, PSP-P and PAGF. Quantitative tau pathology assessment was performed in 17 brain regions in 42 cases of pathologically diagnosed PSP (22 RS, 14 PSP-P and 6 PAGF). Neurofibrillary tangles, tufted astrocytes, coiled bodies and thread pathology were quantitated and a grading system was developed separately for each region. Using these grades the overall tau load was calculated in each case. To establish a simplified system for grading the severity of tau pathology, all data were explored to identify the minimum number of regions that satisfactorily summarized the overall tau severity. The subthalamic nucleus, substantia nigra and globus pallidus were consistently the regions most severely affected by tau pathology. The mean severity in all regions of the RS group was higher than in PSP-P and PAGF, and the overall tau load was significantly higher in RS than in PSP-P (P = 0.002). Using only the grade of coiled body + thread lesions in the substantia nigra, caudate and dentate nucleus, a reliable and repeatable 12-tiered grading system was established (PSP-tau score: 0, mild tau pathology, restricted distribution; >7, severe, widespread tau pathology). PSP-tau score was negatively correlated with disease duration (Spearman's rho -0.36, P = 0.028) and time from disease onset to first fall (Spearman's rho -0.49, P = 0.003). The PSP-tau score in PSP-P (median 3, range 0-5) was significantly lower than in RS (median 5, range 2-10, Mann-Whitney U, P < 0.001). The two cases carrying the tau-H2 protective allele had the two lowest PSP-tau scores. We have identified significant pathological differences between the major clinical syndromes associated with PSP-tau pathology and the restricted, mild tau pathology in PSP-P supports its clinical distinction from RS. The grading system we have developed provides an easy-to-use and sensitive tool for the morphological assessment of PSP-tau pathology and allows for consideration of the clinical diversity that is known to occur in PSP.

The frontotemporal lobar degenerations (FTLDs) are a group of disorders in which the clinical picture is not necessarily predictive of the underlying neuropathology. The FTLD with ubiquitin-only-immunoreactive neuronal changes (FTLD-U) subtype is pathologically characterized by ubiquitin-positive, tau and alpha-synuclein-negative neuronal cytoplasmic inclusions in the frontotemporal cortex and hippocampal dentate fascia. When similar pathological changes are accompanied by histological features of motor neuron disease (MND), the term FTLD-MND is used. The latter pathological changes may be found in patients with or without clinical evidence of MND. We retrospectively reviewed the clinical details of three patients with a rapidly progressive, levodopa-unresponsive bradykinetic-rigid syndrome and frontal cognitive impairment. A diagnosis of progressive supranuclear palsy (PSP) had been considered in all three cases at initial presentation. Two of the cases fulfilled clinical diagnostic criteria for PSP, which was the final clinical diagnosis during life. Pathological analysis showed typical histological appearances of FTLD-MND in two cases and of FTLD-U in one case. Semi-quantitative analysis of pathological load seemed to correlate with the clinical phenotype. FTLD-U or FTLD-MND should be considered in the differential diagnosis of progressive frontal dementia with an akinetic rigid syndrome and supranuclear gaze palsy or Steele-Richardson-Olszewski disease.

Two mutations in the DJ-1 gene on chromosome1p36 have been identified recently to cause early-onset, autosomal recessive Parkinson's disease. As no information is available regarding the distribution of DJ-1 protein in the human brain, in this study we used a monoclonal antibody for DJ-1 to map its distribution in frontal cortex and substantia nigra, regions invariably involved in Parkinson's disease. Western blotting of human frontal cortex showed DJ-1 to be an abundant protein in control, idiopathic Parkinson's disease, cases with clinical and pathological phenotypes of Parkinson's disease with R98Q polymorphism for DJ-1, and in progressive supranuclear palsy (PSP) brains. We also showed that DJ-1 immunoreactivity (IR) was particularly prominent in astrocytes and astrocytic processes in both control and Parkinson's disease frontal cortex, whereas neurons showed light or no DJ-1 IR. Only occasional Lewy bodies (LBs), the pathological hallmarks of Parkinson's disease, showed faint DJ-1 IR, localized to the outer halo. In preclinical studies we showed that DJ-1 is expressed in primary hippocampal and astrocyte cultures of mouse brain. By 2D gel analysis we also showed multiple pI isoforms for DJ-1 ranging between 5.5-6.6 in both control and Parkinson's disease brains, whilst exposure of M17 cells to the oxidizing agent paraquat was manifested as a shift in pI of endogenous DJ-1 towards more acidic isoforms. We conclude that DJ-1 is not an essential component of LBs and Lewy neurites, is expressed mainly by astrocytes in human brain tissue and is sensitive to oxidative stress conditions. These results are consistent with the hypothesis that neuronal-glial interactions are important in the pathophysiology of Parkinson's disease.

We have identified two groups of patients with clinically typical and atypical, pathologically diagnosed progressive supranuclear palsy (PSP), and investigated their genetic and molecular pathological characteristics. Those with clinically typical PSP are more likely to have the PSP susceptibility genotype and to have the deposition of PSP-type hyperphosphorylated tau protein. The clinically atypical PSP group contains a number of different clinical syndromes, including an L-dopa unresponsive bradykinetic syndrome and a clinical syndrome closely resembling idiopathic Parkinson's disease. The clinically atypical PSP group are less likely to have the PSP susceptibility genotype and often have the deposition of Alzheimer's disease paired helical filament type hyperphosphorylated tau. This study suggests that the tau PSP susceptibility genotype is most strongly associated with clinically typical PSP. Neurofibrillary tangle parkinsonian disorders, which pathologically resemble PSP but involve the deposition of Alzheimer's disease-type tau often without involvement of the tau susceptibility genotype, need to be distinguished for diagnostic and research purposes.

Familial Danish dementia (FDD) is pathologically characterized by widespread cerebral amyloid angiopathy (CAA), parenchymal protein deposits, and neurofibrillary degeneration. FDD is associated with a mutation of the BRI2 gene located on chromosome 13. In FDD there is a decamer duplication, which abolishes the normal stop codon, resulting in an extended precursor protein and the release of an amyloidogenic fragment, ADan. The aim of this study was to describe the major neuropathological changes in FDD and to assess the distribution of ADan lesions, neurofibrillary pathology, glial, and microglial response using conventional techniques, immunohistochemistry, confocal microscopy, and immunoelectron microscopy. We showed that ADan is widely distributed in the central nervous system (CNS) in the leptomeninges, blood vessels, and parenchyma. A predominance of parenchymal pre-amyloid (non-fibrillary) lesions was found. Abeta was also present in a proportion of both vascular and parenchymal lesions. There was severe neurofibrillary pathology, and tau immunoblotting revealed a triplet electrophoretic migration pattern comparable with PHF-tau. FDD is a novel form of CNS amyloidosis with extensive neurofibrillary degeneration occurring with parenchymal, predominantly pre-amyloid rather than amyloid, deposition. These findings support the notion that parenchymal amyloid fibril formation is not a prerequisite for the development of neurofibrillary tangles. The significance of concurrent ADan and Abeta deposition in FDD is under further investigation.

The expression of tissue-type plasminogen activator (t-PA) and a number of metalloproteases as well as plasminogen activator inhibitor-1 (PAI-1) and tissue inhibitor of metalloproteases-1 (TIMP-1) was analyzed in the central nervous system (CNS) of normal control and multiple sclerosis (MS) cases by immunohistopathology. The expression of t-PA was detectable only in the blood vessel matrix in control white matter, but positive infiltrating mononuclear cells were also observed in MS white matter and primary lesions. In active plaques this pattern converted to strong positivity of foamy macrophages in areas of demyelination, declining in chronic lesions. In general PAI-1 expression paralleled that of t-PA. Gelatinase A and B were detected predominantly in astrocytes and microglia throughout normal control white matter, with additional positive mononuclear cells in perivascular cuffs in MS white matter. In the demyelinating lesion there is widespread prominent expression of gelatinase B in reactive astrocytes and macrophages, which persists in astrocytes in the chronic lesion. TIMP-1 was also present in the vessel matrix and in lesional macrophages. These observations on the coexpression of enzymes and inhibitors of the matrix degrading cascade in CNS tissue pinpoint t-PA, a rate-limiting enzyme, and gelatinase B as therapeutic targets in MS.

A blood culture study comparing the performance of the new high-volume Bactec resin media to hypertonic medium was conducted in adult patients seen in the emergency department. Twenty milliliters of blood was divided equally among three media: hypertonic (NR8A), aerobic high-volume resin (HV26), and anaerobic high-volume resin (HV27). During a 5.5-month period, 2,724 blood cultures were collected; there were 417 (15.3%) positive cultures, of which 233 (8.6%) yielded pathogens and 184 (6.8%) contaminants. For the 257 isolates recovered from 233 cultures yielding pathogens, the isolation rates were: NR8A-194 (75.5%), HV26-204 (79.4%), and HV27-189 (73.5%). We conclude that in this emergency department patient population, the rate and speed of recovery of pathogenic microorganisms is comparable in high-volume resin media and the hypertonic medium but that the high-volume resin media still has a definite advantage over standard nonradiometric media in adults because high-volume blood cultures (20 mL) can be performed using a two-bottle collection set rather than a three-bottle set.

A study to determine the necessity of routine blind subcultures when using the radiometric BACTEC-460 instrument for detection of bacteremia was conducted. In the first phase, blind subcultures were performed on day 10 of incubation; in the second phase, blind subcultures were performed on day 4; in the final phase the subculture was performed on day one. During the study, 6,208 blood cultures from 2,455 patients were inoculated into three different culture media. There were 454 microbial isolates recovered, including 269 presumed pathogenic isolates. The single significant discrepancy between blind subculture and radiometric detection was a case of Staphylococcus epidermidis septicemia in which the organism was detected 48 hours earlier by blind subculture. There were no cultures in which significant bacterial isolates were detected by blind subcultures but not radiometrically. Thus, under the conditions of this study, routine blind subcultures are not necessary when using the BACTEC radiometric system for detection of bacteremia.

A study to determine the value of the BACTEC resin-containing medium, 16B, used in conjunction with radiometric detection of bacteremia using three media was conducted. During a six-month period, 2,104 blood-culture sets consisting of the four media (6B, 7C, 8B, and 16B) were collected. There were 158 significant positive cultures (excluding contaminants) that yielded 168 pathogenic isolates. The data were divided into two patient groups: patients receiving antibiotics and patients not receiving antibiotics. In contrast to previous studies, there was no significant difference in the detection rate of significant positive cultures by the different media in either group of patients. However, in patients receiving antimicrobial therapy, 41 of 55 significant positive cultures (74.5%) were detected by 16B medium, while 34 of 55 (61.8%) were detected by 6B medium. Although this difference is not statistically significant, this trend suggests that 16B medium may be useful in these patients. However, the isolation rate of significant positive cultures is the same for the resin medium and the hypertonic aerobic medium for both groups of patients. Thus, it is possible that the hypertonic medium is as efficacious as resin-containing media in blood culturing.

This study evaluates the importance of low-colony-count bacteriuria (less than 10(5) CFU/mL) in septicemia originating from urinary tract infections. In a 14-month period, 260 episodes of septicemia occurred. No clinical or microbiologic evidence for a source other than the urinary tract was evident in 68 (26.2%) cases. Of these 68 patients, 13 (19.1%) had colony counts less than 10(5) CFU/mL, and 6 of the 13 had colony counts less than 10(4) CFU/mL. Nine of the infections were community acquired and four were nosocomial. None of the nosocomial cases were associated with an indwelling catheter; four of the 13 patients were receiving chemotherapy and/or steroid therapy. These data support the thesis that some cases of septicemia in patients other than acutely dysuric women, can be caused by UTIs with low colony counts.

A 58-year-old woman had a central nervous system shunt infection and septicemia caused by Propionibacterium acnes. During a two-year period, many Becton-Dickinson blood cultures (18 of 39) were positive for P. acnes, but all BACTEC blood cultures (15) were negative. Parallel cultures in the two commercial media performed simultaneously on the same blood samples several times resulted in a positive Becton-Dickinson culture and a negative BACTEC culture. This case reemphasizes that some bacterial isolates may not be detected when using only one commercial blood culture medium. Thus, if many blood cultures are negative for patients who have clinical features suggestive of septicemia, other types of blood culture media should be inoculated.

This study evaluates the sensitivity and detection time of a new radiometric broth (BACTEC 13A medium, Johnston Laboratories, Towson, MD) designed for direct blood culturing for Mycobacteria. A total of 1,848 blood specimens were cultured in parallel by a new method in which blood was directly inoculated into 13A medium and a comparative method involving lysis-centrifugation and inoculation of 7H11 agar and 7H12 broth media. There were 65 blood cultures with positive results (64 Mycobacterium avium-intracellulare and 1 Mycobacterium tuberculosis) from 43 patients. For the direct inoculation and lysis-centrifugation methods, the recovery rates were 96.9% and 98.5%, respectively, and the mean times to detection were essentially the same (23.6 and 23.8 days, respectively). Thus, the direct-inoculation technique using 13A medium showed performance equivalent to the lysis-centrifugation method. Also, the direct method has the advantage of elimination of the time-consuming manual manipulations that are required by lysis-centrifugation methods.

A study to determine the value of the Antimicrobial Removal Device (ARD) used in conjunction with radiometric detection of bacteremia using three media was conducted. During a 12-month period, 622 duplicate ARD/BACTEC blood-culture sets were collected. There were 88 positive cultures that yielded 68 pathogenic isolates and 28 probable contaminant isolates. When all patients were considered, 31 pathogenic isolates were detected by both systems, 25 pathogenic isolates were detected faster or only by the BACTEC system, and 12 pathogenic isolates were detected faster or only when the ARD was employed. This difference is statistically significant (P less than 0.05). Thus, the standard BACTEC blood-culture system using three different media was superior to the same BACTEC system using ARD-processed blood specimens. When only patients receiving antimicrobial therapy were considered, there were more pathogenic isolates detected from unprocessed blood than from blood processed in the ARD; however, this difference was not statistically significant. In conclusion, there appears to be no advantage to using the ARD system in conjunction with the three-bottle BACTEC blood-culture system.

This is a study of 130 matched venipuncture and intravascular blood cultures collected from 53 patients. In 99 cultures (76.1%), both the venipuncture and the catheter specimens were negative. There were six matched cultures yielding significant isolates: in three both the venipuncture and intravascular specimens were positive; in two only the intravascular specimen was positive; and in one only the venipuncture specimen was positive. Twenty-five cultures were positive from the intravascular specimen only, and 23 of these were classified as contaminated cultures. Thus, the contamination rate was significantly higher in the intravascular catheter blood culture specimens (P less than 0.001). These results indicate that blood culture specimens should not be routinely collected from intravascular catheters unless collection by venipuncture is impossible.

Cystic vaginal adenosis was diagnosed in a 31-year-old woman. This lesion regressed promptly following the cessation of an oral contraceptive (Ovulen-21) which had been used continuously for 5 years. The temporal relationship between discontinuation of contraceptive treatment and the regression strongly suggests that the medication played a causal role in producing cystic vaginal adenosis. A possible mechanism may have been the stimulation of quiescent glands to growth and cystic dilatation, which finally produced a lesion associated with clinical symptoms.