Biomedical subjects

S Jang

Publications and source records attributed to S Jang.

At least 19 recordsLinked to original sources

PubMed2006

Aging sensitizes mice to behavioral deficits induced by central HIV-1 gp120.

The number of older adults with HIV-1 disease is increasing but little is known about how age influences behavioral deficits associated with HIV-1 infection. The purpose of this study was to determine in a murine model if aging influenced sickness behavior following central injection of HIV-1 gp120. In initial studies, behavioral deficits induced by acute and repeated intracerebroventricular (ICV) injection of gp120 were greater in aged mice than in adults. Furthermore, repeated ICV injection of gp120 increased hippocampal levels of IL-1 beta and IL-6 mRNA in aged mice but not in adults. To determine if IL-6, which is elevated in aged brain, affects expression of the gp120-binding target, CCR5, microglia (BV-2 cell line) were incubated with increasing concentrations of IL-6. Cell surface expression of CCR5 was increased by IL-6 in a dose-dependent manner. Additionally, IL-6 increased gp120-dependent chemotaxis. These results suggest that aging increases the sensitivity of mice to behavioral deficits caused by ICV gp120, perhaps by increasing expression of CCR5 and augmenting production of cytokines.

Aging↗

PubMed2006

Salmonella spp., Vibrio spp., Clostridium perfringens, and Plesiomonas shigelloides in marine and freshwater invertebrates from coastal California ecosystems.

The coastal ecosystems of California are highly utilized by humans and animals, but the ecology of fecal bacteria at the land-sea interface is not well understood. This study evaluated the distribution of potentially pathogenic bacteria in invertebrates from linked marine, estuarine, and freshwater ecosystems in central California. A variety of filter-feeding clams, mussels, worms, and crab tissues were selectively cultured for Salmonella spp., Campylobacter spp., Escherichia coli-O157, Clostridium perfringens, Plesiomonas shigelloides, and Vibrio spp. A longitudinal study assessed environmental risk factors for detecting these bacterial species in sentinel mussel batches. Putative risk factors included mussel collection near higher risk areas for livestock or human sewage exposure, adjacent human population density, season, recent precipitation, water temperature, water type, bivalve type, and freshwater outflow exposure. Bacteria detected in invertebrates included Salmonella spp., C. perfringens, P. shigelloides, Vibrio cholerae, Vibrio parahaemolyticus, and Vibrio alginolyticus. Overall, 80% of mussel batches were culture positive for at least one of the bacterial species, although the pathogens Campylobacter, E. coli-O157, and Salmonella were not detected. Many of the same bacterial species were also cultured from upstream estuarine and riverine invertebrates. Exposure to human sewage sources, recent precipitation, and water temperature were significant risk factors for bacterial detection in sentinel mussel batches. These findings are consistent with the hypothesis that filter-feeding invertebrates along the coast concentrate fecal bacteria flowing from land to sea and show that the relationships between anthropogenic effects on coastal ecosystems and the environmental niches of fecal bacteria are complex and dynamic.

Animals↗

PubMed2005

Model systems for evaluating factors affecting acrylamide formation in deep fried foods.

Simulated food pieces constructed from fiberglass pads (models for French fries and chips) were used as carriers for defined aqueous solutions, dispersions of test substances and ingredients to evaluate acrylamide formation. The pads were loaded with a solution containing asparagine and glucose (10 mM each) plus selected reaction modulators before deep fat frying and analysis for acrylamide. Data from fiberglass models along with companion sliced potato samples were used in developing hypotheses for the mechanisms involved in the suppression of acrylamide formation by polyvalent cations, polyanionic compounds, pH, and altered food polymer states in fried potato products.

Acrylamide↗

PubMed2005

Combustion characteristics of paper mill sludge in a lab-scale combustor with internally cycloned circulating fluidized bed.

After performing a series of batch type experiments using a lab-scale combustor, consideration was given to the use of an internally cycloned circulating fluidized bed combustor (ICCFBC) for a paper mill sludge. Operation parameters including water content, feeding mass of the sludge, and secondary air injection ratio were varied to understand their effects on combustion performance, which was examined in terms of carbon conversion rate (CCR) and the emission rates of CO, C(x)H(y) and NO(x). The combustion of paper mill sludge in the ICCFBC was compared to the reaction mechanisms of a conventional solid fuel combustion, characterized by kinetics limited reaction zone, diffusion limited reaction zone, and transition zone. The results of the parametric study showed that a 35% water content and 60 g feeding mass generated the best condition for combustion. Meanwhile, areal mass burning rate, which is an important design and operation parameter at an industrial scale plant, was estimated by a conceptual equation. The areal mass burning rate corresponding to the best combustion condition was approximately 400 kg/hm(2) for 35% water content. The secondary air injection generating swirling flow enhanced the mixing between the gas phase components as well as the solid phase components, and improved the combustion efficiency by increasing the carbon conversion rate and reducing pollutant emissions.

Air Pollutants↗

PubMed2005

Treatment of relapsed acute lymphoblastic leukemia after allogeneic bone marrow transplantation with chemotherapy followed by G-CSF-primed donor leukocyte infusion: a prospective study.

Donor leukocyte infusion (DLI) alone has very limited efficacy for patients with acute lymphoblastic leukemia (ALL) who have relapsed after allogeneic bone marrow transplantation (BMT). We, therefore, prospectively tested the efficacy of cytoreductive chemotherapy (intermediate-dose cytarabine+idarubicin+etoposide) followed immediately by G-CSF-primed DLI (Chemo-DLI) in 10 relapsed ALL patients after allogeneic BMT. Seven achieved complete remission (CR) at a median of 25 days (19-73 days) after DLI. Of these seven CR patients, only one remains alive in CR 907 days after DLI. Two CR patients died in CR of graft-versus-host disease. The remaining four CR patients relapsed at a median of 153 days (120-991 days) after DLI. One is alive with leukemia at post-DLI day 1217. The median survival duration after DLI was 175 days (15-1217 days). In summary, although Chemo-DLI for relapsed ALL after allogeneic BMT induced a relatively high CR rate, durable remissions were rare. Although our data should be interpreted cautiously considering the small number of patients, these results suggest that poor outcome of DLI in relapsed ALL may be primarily due to intrinsic resistance to graft-versus-leukemia effect rather than to the rapid pace of the disease.

Adult↗

PubMed2005

Clinical effect of imatinib added to intensive combination chemotherapy for newly diagnosed Philadelphia chromosome-positive acute lymphoblastic leukemia.

Clinical impact of imatinib was evaluated in 20 patients (median age, 37 years; range, 15-67 years) with newly diagnosed Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ ALL), who were administered with induction chemotherapy of daunorubicin, vincristine, prednisolone, and L-asparaginase, along with imatinib 600 mg/day during remission induction and 400 mg/day during consolidation courses. One patient died on day 14 from septic shock, while the remaining 19 achieved complete remission (CR). In total, 15 patients underwent allogeneic hematopoietic cell transplantation (HCT) during first CR. After median follow-up period of 799 days, six patients experienced recurrence; two with early recurrence within 100 days, one with leptomeningeal recurrence at 11 month, and three with post-HCT recurrence. Eight patients died. Median CR duration (821 days) and median patient survival (894 days) in the study were significantly longer by 2.9- and 2.3-fold, respectively, when compared to those of 18 historical patients treated with same regimen of combination chemotherapy without imatinib. Toxicities of the combined treatment were manageable and included grade 4 myelosuppression (n = 20) and reversible > or = grade 3 hyperbilirubinemia (n = 4). Beneficial clinical effects were observed when imatinib was added to combination chemotherapy in patients with newly diagnosed Ph+ ALL. Further studies with larger number of patients are necessary.

Adolescent↗

PubMed2005

Identification of a 71 kDa protein as a putative non-genomic membrane progesterone receptor in boar spermatozoa.

A putative non-genomic progesterone receptor was identified by Western blot analysis from the membrane fraction but not the cytosolic fraction of boar spermatozoa using monoclonal antibody (mAb) C-262. When the membrane and the cytosolic fractions of boar liver, kidney, uterus and spermatozoa were analyzed with mAb C-262, protein bands with molecular masses of 86 and 120 kDa were detected from the cytosolic fraction of the uterus, whereas a 71 kDa protein was detected from the membrane fraction of spermatozoa. Apparently, while the 86 and 120 kDa proteins from the uterus correspond to the genomic progesterone receptor isoforms A and B in boar, the 71 kDa protein of the sperm membrane fraction seems to be a novel membrane-associated progesterone receptor. Ligand blot assay of the membrane and the cytosolic fractions of boar spermatozoa performed with peroxidase-conjugated progesterone revealed that only the 71 kDa membrane protein binds specifically to progesterone, reinforcing the results obtained from the Western blot analysis. Also ligand blot assays performed in the presence of mAb C-262 demonstrated that mAb C-262 inhibited progesterone binding to the 71 kDa protein in a dose-dependent manner. Ligand blot assays performed in the presence of free progesterone, RU486 or estrogen revealed that binding of peroxidase-conjugated progesterone to the 71 kDa protein was inhibited by free progesterone and RU486 in a dose-dependent manner but not by estrogen, which further confirms that progesterone binds to the 71 kDa protein specifically. Furthermore, the progesterone-induced acrosome reaction was inhibited by mAb C-262 in a dose-dependent manner. These results strongly imply that spermatozoa possess a progesterone receptor in a membrane-bound form and can be influenced by progesterone via non-genomic progesterone receptor.

Acrosome Reaction↗

PubMed2001

Virulence factors in Escherichia coli isolated from the blood of bacteremic neonatal calves.

Twenty-five Escherichia coli isolates from the blood of critically ill bacteremic calves sampled in two separate studies on a calf-rearing farm housing over 15,000 calves, in the San Joaquin Valley, California were studied. Isolates were characterized for O serogroups and for pathotypes as determined by the presence of specific virulence factors including heat-labile enterotoxin (LT), heat-stable enterotoxins a and b (STa, STb), verotoxins 1 and 2 (VT1, VT2), cytotoxic necrotizing factor (CNF), aerobactin, intimin Eae and P, F17 and CS31A fimbrial adhesins, and resistance to bactericidal effects of serum. These isolates constituted a heterogeneous group. However, isolates were mostly aerobactin positive and often resistant to the bactericidal effects of serum. Isolates of pathotypes O78 (n=6), O119:CS31a (n=3), and P positive but O non-typeable (n=3) were associated with a high mortality rate. The remaining isolates belonged to diverse pathotypes, often possessing the adhesins P, F17, CS31A and Eae but belonging to O serogroups other than O78 and O119, and were less frequently associated with mortality. Although no virulence factor common to all isolates was identified, the capacity to use iron by the presence of aerobactin which is important to the capture of iron was a predominant factor. Moreover, certain pathotypes appear to be associated with primary colisepticemia whereas other pathotypes may cause a bacteremia without necessarily leading to septicemia.

Adhesins, Bacterial↗

PubMed2001

Inter-modality comparisons of seizure focus lateralization in complex partial seizures.

Anterior temporal lobectomy offers a high chance of seizure-free outcome in patients suffering from drug-refractory complex partial seizure (CPS) originating from the temporal lobe. Other than EEG, several functional and morphologic imaging methods are used to define the spatial seizure origin. The present study was undertaken to compare the merits of fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET), magnetic resonance imaging (MRI) and single-voxel proton MR spectroscopy (MRS) for the lateralization of temporal lobe seizure foci. The clinical charts and imaging data of 43 consecutive CPS patients were reviewed. Based on surface EEG, 31 patients were classified with temporal lobe epilepsy (TLE; 25 lateralized, 6 not lateralized) and 12 with non-temporal lobe epilepsy. All were examined by FDG-PET, MRS and MRI within 6 weeks. FDG-PET and MRI were interpreted visually, while the N-acetyl-aspartate to creatine ratio was used for MRS interpretation. One FDG-PET scan was invalid due to seizure activity post injection. The MR spectra could not be evaluated in five cases bilaterally and three cases unilaterally for technical reasons. A total of 15 patients underwent anterior temporal lobectomy. All showed a beneficial postoperative outcome. When the proportions of agreement between FDG-PET (0.77), MRI (0.58) and MRS (0.56) and surface EEG in TLE cases were compared, there were no significant differences (P>0.10). However, FDG-PET showed a significantly higher agreement (0.93) than MRI (0.60; P=0.03) with the side of successful temporal lobectomy. The concordance of MRS with the side of successful temporal lobectomy was intermediate (0.75). When the results of functional and morphologic imaging were combined, no significant differences were found between the rates of agreement of FDG-PET/MRI and MRS/MRI with EEG (0.80 vs 0.68; P=0.50) and with the side of successful temporal lobectomy (0.87 vs 0.92; P=0.50) in TLE cases. However, MRS/MRI showed significantly more lateralized temporal lobe abnormalities in non-temporal lobe epilepsy cases than FDG-PET/MRI (0.90 vs. 0.17; P<0.01). Although FDG-PET seems to be the most reliable and stable method for this purpose, we conclude that in TLE cases it may be justified to perform MRS, which is less expensive, faster and has no radiation exposure, in combination with MRI before FDG-PET, since FDG-PET offers little additional diagnostic information if MRS and MRI indicate the same seizure focus lateralization.

Adolescent↗

PubMed2001

F-18 FDG uptake in the large arteries: a new observation.

PURPOSE: The cellular components of the atherosclerotic plaque, such as macrophages, exhibits high glucose metabolic activity. The aim of this study was to show the frequency of vascular uptake and possibly to explain the significance of this finding on fluorodeoxyglucose (FDG) positron emission tomographic (PET) scans. METHODS: We evaluated the presence of FDG vascular uptake in 132 consecutive patients undergoing whole-body PET scans and 5 patients who had only lower extremity scans. The presence of vascular FDG uptake was assessed in the abdominal aorta, iliac, and proximal femoral arteries on the 132 whole-body scans, whereas only the femoral and the popliteal arteries were examined on the leg scans. The patients' ages ranged from 20 to 80 years, and they were divided into three age groups: 35 patients were younger than 40 years (group 1; mean age, 32.4 years), 48 patients were 41 to 60 years (group 2; mean age, 50.3 years), and 54 patients were older than 60 years (group 3; mean age, 70.3 years). RESULTS: Fifty percent (69 of 137) of the total population showed vascular FDG uptake in at least one vessel. Thirty-four percent (12 of 35) of group 1, 50% (24 of 48) of group 2, and 61% (33 of 54) of group 3 showed vascular wall uptake (P = 0.017 between groups 1 and 3). In addition, the correlation between the mean age of the age groups and the prevalence of FDG vascular uptake is strong (r = 0.99). CONCLUSIONS: Vascular FDG uptake is present in 50% of the patients examined for this study, with an increased prevalence in older patients. This vascular uptake might be explained by smooth muscle metabolism in the media, subendothelial smooth muscle proliferation from senescence, and the presence of macrophages within the atherosclerotic plaque. The relative contribution of these sources needs further investigation.

Adult↗

PubMed2001

Apolipoprotein E polymorphism and serum lipoprotein(a) concentrations in a Korean male population.

The purpose of this study was to investigate the effect of apolipoprotein E polymorphism on lipoprotein(a) metabolism by comparing serum lipoprotein(a) concentration with apolipoprotein E genotype in a Korean male population whose high molecular weight (HMW) lipoprotein(a) frequency was 95-98%. Serum lipoprotein(a), total cholesterol, triglyceride and high-density lipoprotein-cholesterol concentrations were measured and the apolipoprotein E genotype determined in 1189 healthy Korean males. The medians of serum lipoprotein(a) concentration in the apo E 2/3 group (0.105 g/L) and the apo E 3/4 group (0-116 g/L) were significantly lower than that in the apo E 3/3 group (0.155 g/L; P < 0.001). The medians of serum triglyceride were 1.497 mmol/L in the apo E 2/3 group, 1.356 mmol/L in the apo E 3/4 group, and 1.452 mmol/L in the apo E 3/3 group (P<0.05). With the significant difference in the serum lipoprotein(a) concentration in Korean males according to apolipoprotein E genotype, and with the negative correlation between serum triglyceride concentration and serum lipoprotein(a) concentration, it is suggested that apolipoprotein E polymorphism and serum triglyceride participate in the metabolism of lipoprotein(a) with HMW.

Apolipoproteins E↗

PubMed2001

Developing CD-ROM based multimedia digital textbook of 'San-Yin-Jiao(SP-6) pressure for reducing the labor pain and shortening the labor time'.

The computer-based textbook is a new educational tool that promises to play a prominent role in the coming years. Classical instructional technologies, such as video, stills, audio files and computer programs with a textbook orientation, have been merged into one multimedia computer system and have created additional opportunities for learning in medical, dental and nursing education. The authors developed a hypermedia textbook of â San-Yin-Jiao pressure for reducing the labor pain and shortening the labor time' using a personal computer with hypermedia software that contains texts, images, videos, audios and literature citations. The target population of this educational CD-ROM would be nurse-midwives, clinical nurses working for the obstetric units, and faculty members who teach the Maternity and Women's Health Nursing. Valuable and practical experiences were obtained and shared.

Acupressure↗

PubMed2001

18F-FDG PET in characterizing adrenal lesions detected on CT or MRI.

UNLABELLED: The purpose of this study was to evaluate the ability of (18)F-FDG PET to characterize adrenal lesions in patients with proven or suspected cancers. METHODS: A retrospective analysis was performed on 50 adrenal lesions in 41 patients, whose PET scans were done to evaluate the primary or metastatic disease. CT had shown 50 adrenal lesions in 41 patients and MRI had revealed 13 lesions in 10 patients. There were 34 patients with proven malignancy (28 lung cancer, 3 thyroid cancer, 2 colorectal cancer, and 1 lymphoma) and 7 with lung nodules. Of the 50 lesions, 18 were eventually determined to be malignant either by histopathology (n = 7) or by follow-up (n = 11). The remaining 32 lesions were proven or assumed to be benign by histopathology (n = 4) or clinical follow-up (n = 28). Unlike previously published reports, PET was interpreted as positive if the uptake was equal to or greater than that of the liver. RESULTS: No malignant lesion yielded a negative result on PET. Most lesions (13/18) showed significantly higher FDG uptake than that of the liver. In the remaining 5 lesions (2 metastases from neuroendocrine tumor, 2 early metastases, and 1 necrotic metastasis), FDG uptake was equal to or slightly higher than that of the liver. Of the 32 benign lesions, there were 2 lesions with uptake equal to or slightly higher than that of the liver, 3 with uptake less than the liver but more than the background, and 27 with uptake of the background. MRI identified 3 of the 13 lesions as false-positives but FDG PET correctly identified all 3 as benign. The other 10 adrenal lesions accurately diagnosed by MRI were also characterized by PET. FDG PET for characterization of adrenal lesions showed a sensitivity of 100%, a specificity of 94%, and an accuracy of 96%. CONCLUSION: FDG PET showed excellent diagnostic performance in differentiating adrenal lesions detected on CT or MRI. Because FDG PET has the additional advantage of evaluating the primary lesions as well as metastases, it could be cost-effective and the modality of choice for the characterization of adrenal lesions, especially in patients with malignancy.

Adrenal Gland Diseases↗

PubMed2000

Impact of attenuation correction on the accuracy of FDG-PET in patients with abdominal tumors: a free-response ROC analysis.

The aim of this study was to evaluate image quality and lesion detectability with and without attenuation correction in patients with abdominal tumors, using a free-response receiver operating characteristic (FROC) methodology. Thirty-four patients with various abdominal tumors were evaluated (11 men, 23 women, median age 48 years). Whole-body emission scans were performed 68 min (35-102 min) after intravenous injection of 4.3 MBq/kg fluorine-18 fluorodeoxyglucose (FDG). Images were reconstructed using the OS-EM algorithm and corrected for attenuation either using postinjection singles transmission (n=27) or by calculation and body outline (n=7). Total scan duration did not exceed 70 min. Studies were read independently by four observers unaware of any clinical data. The uncorrected (UC) images were systematically read before the attenuation-corrected (AC) images. All studies were given an image quality score ranging from 1 (unreadable) to 5 (excellent). Each focus of increased activity was then localized and given a probability of malignancy using a five-point scale. The average image quality score was similar for both UC and AC images. At the time of the positron emission tomography (PET) scans, 127 lesions (63 liver metastases, 9 retroperitoneal lesions, 50 peritoneal or bowel lesions, and 5 pancreatic carcinomas) were revealed by pathological or correlative studies. The areas under the FROC curves were consistently greater for AC images (range 0.8663-0.8867) than for UC images (range 0.7774 -0.8613). Overall, the difference between the AC images and the UC images was significant (P=0.019). In particular, correction for attenuation increased the sensitivity regardless of the location of the lesions. In conclusion, correction for attenuation significantly improves the diagnostic accuracy of FDG-PET for abdominal staging of neoplasms, without impairing the image quality.

Abdominal Neoplasms↗

PubMed2000

Genotyping of Bacteroides fragilis isolates from stool specimens by arbitrarily-primed-PCR.

In order to determine genetic relatedness of Bacteroides fragilis isolates from different clinical sources, arbitrarily primed polymerase chain reaction (PCR) (AP-PCR) was used to compare 17 strains isolated from patients with inflammatory bowel disease (IBD) and 20 strains isolated from foals with diarrhea. Three reference ATCC strains were also analyzed. Eighteen unique types were identified with a 22-mer arbitrary primer (ERIC-2) among the 20 patient isolates. Types 1 (enterotoxigenic) and 9 (nonenterotoxigenic), were each found in the stools of two patients. All other isolates showed a distinct and unique DNA banding pattern indicating a high degree of genotypic variability. Eleven types were identified among the foal isolates. Type 20, a nonenterotoxigenic type, was present in 30% of the foals. No correlation was found between the human and horse isolates. No clear relationship between a disease state (diarrhea or IBD) and specific types was observed. AP-PCR will be useful as a rapid method to determine genetic relatedness and in future epidemiologic studies of diarrheal diseases due to B. fragilis.

Animals↗

PubMed2000

T-DNA insertional mutagenesis for functional genomics in rice.

We have produced 22 090 primary transgenic rice plants that carry a T-DNA insertion, which has resulted in 18 358 fertile lines. Genomic DNA gel-blot and PCR analyses have shown that approximately 65% of the population contains more than one copy of the inserted T-DNA. Hygromycin resistance tests revealed that transgenic plants contain an average of 1.4 loci of T-DNA inserts. Therefore, it can be estimated that approximately 25 700 taggings have been generated. The binary vector used in the insertion contained the promoterless beta-glucuronidase (GUS) reporter gene with an intron and multiple splicing donors and acceptors immediately next to the right border. Therefore, this gene trap vector is able to detect a gene fusion between GUS and an endogenous gene, which is tagged by T-DNA. Histochemical GUS assays were carried out in the leaves and roots from 5353 lines, mature flowers from 7026 lines, and developing seeds from 1948 lines. The data revealed that 1.6-2.1% of tested organs were GUS-positive in the tested organs, and that their GUS expression patterns were organ- or tissue-specific or ubiquitous in all parts of the plant. The large population of T-DNA-tagged lines will be useful for identifying insertional mutants in various genes and for discovering new genes in rice.

Base Sequence↗

PubMed2000

leafy hull sterile1 is a homeotic mutation in a rice MADS box gene affecting rice flower development.

Rice contains several MADS box genes. It has been demonstrated previously that one of these genes, OsMADS1 (for Oryza sativa MADS box gene1), is expressed preferentially in flowers and causes early flowering when ectopically expressed in tobacco plants. In this study, we demonstrated that ectopic expression of OsMADS1 in rice also results in early flowering. To further investigate the role of OsMADS1 during rice flower development, we generated transgenic rice plants expressing altered OsMADS1 genes that contain missense mutations in the MADS domain. There was no visible alteration in the transgenic plants during the vegetative stage. However, transgenic panicles typically exhibited phenotypic alterations, including spikelets consisting of elongated leafy paleae and lemmas that exhibit a feature of open hull, two pairs of leafy palea-like and lemma-like lodicules, a decrease in stamen number, and an increase in the number of carpels. In addition, some spikelets generated an additional floret from the same rachilla. These characteristics are very similar to those of leafy hull sterile1 (lhs1). The map position of OsMADS1 is closely linked to that of lhs1 on chromosome 3. Examination of lhs1 revealed that it contains two missense mutations in the OsMADS1 MADS domain. A genetic complementation experiment showed that the 11.9-kb genomic DNA fragment containing the wild-type OsMADS1 gene rescued the mutant phenotypes. In addition, ectopic expression of the OsMADS1 gene isolated from the lhs1 line resulted in lhs1-conferred phenotypes. These lines of evidence demonstrate that OsMADS1 is the lhs1 gene.

Amino Acid Sequence↗

PubMed2000

Pyogranulomatous meningoencephalitis due to Actinomyces sp. in a dog.

Actinomyces sp. are commensal, filamentous, gram-positive, acid-fast-negative bacteria that can cause pyogranulomatous inflammation in animals and humans. Central nervous system (CNS) disease is a rare presentation of actinomycosis and is usually due to extension from infected wounds or seeding from distant sites. A dog with progressive, poorly localized neurologic signs had primary CNS actinomycosis without history or evidence of previous trauma or other organ involvement. Histologically, there was a severe pyogranulomatous meningoencephalitis with intralesional filamentous bacteria that were also visible on cytology of the cerebral spinal fluid (CSF) postmortem. Actinomyces sp. was cultured postmortem from the CSF, confirming the diagnosis. This case demonstrates that Actinomyces sp. can be a causative agent of primary CNS disease in dogs.

Actinomyces↗