In vitro antidermatophytic activity and cytotoxicity of extracts derived from medicinal plants and marine algae.

OBJECTIVES: This study was conducted to evaluate the antidermatophytic activity of 48 extracts obtained from medicinal plants (Cibotium barometz, Melastoma malabathricum, Meuhlenbeckia platyclada, Rhapis excelsa, Syzygium myrtifolium, Vernonia amygdalina) and marine algae (Caulerpa sertularioides, Kappaphycus alvarezii) against Trichophyton rubrum and Trichophyton interdigitale (ATCC reference strains), and the cytotoxicity using African monkey kidney epithelial (Vero) cells. Active plant extracts were screened for the presence of phytochemicals and tested against clinical isolates of Trichophyton tonsurans. METHODS: Six different extracts (hexane, chloroform, ethyl acetate, ethanol, methanol and water) were obtained from each plant or algae sample using sequential solvent extraction. The antidermatophytic activity for the extracts was assessed using a colourimetric broth microdilution method. The viability of Vero cells was measured by Neutral Red uptake assay. RESULTS: All the extracts (except the water extracts of V. amygdalina, C. sertularioides and K. alvarezii) showed antidermatophytic activity against Trichophyton spp. The minimum fungicidal concentration (MFC) ranges for the plant extracts against T. rubrum and T. interdigitale are 0.0025-2.50 and 0.005-2.50mg/mL, respectively. The algae extracts exhibited lower potency against both species, showing MFC ranges of 0.08-2.50 and 0.31-2.50mg/mL, respectively. The ethanol and methanol extracts from the leaves of R. excelsa, and the methanol and water extracts from the leaves of S. myrtifolium were highly active (MFC<0.1mg/mL) and with high selectivity indices (SI>2.8) against reference strains of T. rubrum and T. interdigitale, and most of the clinical isolates of T. tonsurans. Phytochemical analysis indicates the presence of alkaloids, anthraquinones, flavonoids, saponins, tannins, phenolics and triterpenoids in the extracts. CONCLUSIONS: The medicinal plant extracts exhibited stronger antidermatophytic activity compared to the algae extracts. The leaves of R. excelsa and S. myrtifolium are potential sources of new antidermatophytic agents against Trichophyton spp.

Final results of a randomized phase III trial of induction chemotherapy followed by concurrent chemoradiotherapy versus concurrent chemoradiotherapy alone in patients with stage IVA and IVB nasopharyngeal carcinoma-Taiwan Cooperative Oncology Group (TCOG) 1303 Study.

Background: Concurrent chemoradiotherapy (CCRT) is superior to radiotherapy alone for treating locoregionally advanced nasopharyngeal carcinoma (NPC). Whether adding induction chemotherapy (IC) further improves the outcome warrants investigation. Patients and methods: This open-label multicenter phase III trial was conducted at 11 institutions in Taiwan. Patients with stage IVA or IVB NPC were randomized to receive IC followed by CCRT (I-CCRT) or CCRT alone. Patients in the I-CCRT arm received three cycles of mitomycin C, epirubicin, cisplatin, and 5-fluorouracil/leucovorin (MEPFL). All patients received 30 mg/m2 cisplatin weekly during radiotherapy, which was delivered as 1.8-2.2 Gy per fraction with five daily fractions per week, to a total dose of 70 Gy or greater to the primary tumor and 66-70 Gy to the involved neck. The primary end point was disease-free survival (DFS). Results: In this study, 240 and 239 patients were randomized to CCRT and I-CCRT arm, respectively. The most prominent toxicities of induction were leukopenia (grade 3 and 4: 47% and 12%) and thrombocytopenia (grade 3 and 4: 24% and 3%). During radiotherapy, severe mucositis was the major side-effect in both arms; an increased number of patients in the I-CCRT arm had myelosuppression; hence, discontinuation of weekly cisplatin was more common. After a median follow-up of 72.0 months, the I-CCRT arm had significantly higher DFS than that of the CCRT arm [5-year rate 61% versus 50%; hazard ratio=0.739, 95% confidence interval (CI)=0.565-0.965; P = 0.0264], after stratified for N3b and LDH, and adjusted for T stage. Conclusion: Induction with MEPFL before CCRT was tolerable and significantly improved the DFS of patients with stage IVA and IVB NPC though overall survival not improved. Clinical trial information: NCT00201396.

Simultaneous induction of apoptosis and necroptosis by Tanshinone IIA in human hepatocellular carcinoma HepG2 cells.

Tanshinone IIA (Tan IIA), a constituent of the traditional medicinal plant Salvia miltiorrhiza BUNGE, has been reported to possess anticancer activity through induction of apoptosis in many cancer cells. Surprisingly, the present study finds that Tan IIA simultaneously causes apoptosis and necroptosis in human hepatocellular carcinoma HepG2 cells. We further find that apoptosis can be converted to necroptosis by pan-caspase inhibitor Z-VAD-fmk, and the two death modes can be blocked by necroptotic inhibitor necrostatin-1. The underlying mechanisms are revealed by analysis of the signaling molecules using western blotting. In control cells, FLICE inhibitory protein in short form (FLIPS) is expressed in relatively high levels and binds to caspase 8 in ripoptosome, which supposedly sustains cell survival. However, in Tan IIA-treated cells, FLIPS is down-regulated and may thus cause homodimer formation of cleaved caspase 8, cleavage of receptor-interacting serine/threonine-protein kinases 1, 3 (RIP1, RIP3), and mixed-lineage kinase domain-like (MLKL), in turn leads to cell apoptosis. In parallel, Tan IIA causes necroptosis by forming a suggested necrosomal complex composed of RIP1/RIP3. Regarding the inhibitors, z-VAD-fmk diminishes the cleaved caspase 8, RIP1, RIP3, and MLKL induced by Tan IIA, and reconstructs the ripoptosome complex, which marks cells moving from apoptosis to necroptosis. Nec-1 recovers the Tan IIA down-regulated FLIPS, consequently causes FLIPS to form heterodimer with caspase 8 and thus block apoptosis. Meanwhile, cleaved forms of RIP1 and RIP3 were observed preventing necroptosis. Intriguingly, the cytotoxicity of tumor necrosis factor-related apoptosis-inducing ligand to HepG2 cells is enhanced by Tan IIA in a pilot study, which may be attributed to low FLIPS levels induced by Tan IIA. In short, Tan IIA simultaneously induces both Nec-1 inhibition and FLIPS regulation-mediated apoptosis/necroptosis, which has not been previously documented. Moreover, the involvement of the cleavage type of MLKL in executing necroptosis warrants further investigation.

Clinical and genetic analysis of Taiwanese patients with hereditary spastic paraplegia type 5.

BACKGROUND AND PURPOSE: Spastic paraplegia type 5 (SPG5) is an autosomal recessive (AR) hereditary spastic paraplegia (HSP) associated with pure or complicated phenotypes. This study aimed to screen SPG5 in Taiwanese HSP patients. METHODS: Sequencing of the SPG5 gene, CYP7B1, was performed in a cohort of 25 ethnic Han Taiwanese patients with AR or sporadic HSP. Clinical information and magnetic resonance imaging (MRI) were analyzed in confirmed SPG5 patients. RESULTS: One (33%) AR kindred and four (18%) sporadic cases had CYP7B1 mutations. All of the SPG5 cases carried the mutation c.334 C>T (R112X). Haplotype analysis suggested a 'founder effect' in ethnic Hans for this mutation. The phenotype was either pure or complicated by cerebellar ataxia. For the primary HSP phenotype, there were profound dorsal column sensory deficits in all patients. Spine MRI showed thoraco-lumbar cord atrophy in some patients. CONCLUSIONS: Spastic paraplegia type 5 is a common cause of AR and sporadic HSPs that has a higher frequency in Taiwanese than in other ethnic groups. It is associated with a CYP7B1 founder mutation and its phenotype is characterized by pronounced dorsal column sensory loss, with cerebellar ataxia in some patients.

Up-regulation of matrix metalloproteinases-2 and -9 via an Erk1/2/NF-κB pathway in murine mast cells infected with Toxoplasma gondii.

Mast cells are key effectors in inflammation and contain proteinases that are released on activation. This study investigates associations between extracellular signal-regulated kinase (Erk)1/2, nuclear factor (NF)-κB, matrix metalloproteinase (MMP)-2 and MMP-9 in mast cells infected with Toxoplasma gondii tachyzoites. T. gondii infection led to increased mast cell degranulation. Phosphorylated (p)-Erk1/2 and p-NF-κB were increased significantly in mast cells infected with T. gondii. Pretreatment with the Erk kinase inhibitor PD98059 significantly decreased the expression of p-Erk1/2, p-NF-κB, MMP-2 and MMP-9. Treatment with MG132, an indirect NF-κB inhibitor, effectively reduced p-IκBα, p-NF-κB, MMP-2 and MMP-9 expression. Collectively, these data show that suppression of an Erk1/2/NF-κB signalling pathway caused a reduction in MMP-2 and -9 activities. Inhibiting this signalling pathway for MMP-2 and MMP-9 expression might offer a potential way to control early T. gondii infection. This pathway for the generation of MMP-2 and MMP-9 is important for mast cell secretion and the NF-κB/Erk1/2 signalling pathway may be key in MMP-2 and MMP-9 production in host defense against toxoplasmosis.

Fibronectin degradation by MMP-2/MMP-9 in the serum of pregnant women and umbilical cord with Toxoplasma gondii infection.

It has been suggested that in congenital Toxoplasma gondii infections, the parasite reaches the fetus by crossing the placental barrier. The purpose of this study was to determine the possible relationships between matrix metalloproteinases (MMPs) and dysfunction of the placental barrier in gravidas infected with T. gondii. We studied 26 umbilical cord sera; 20 and 6 were derived from gravidas seropositive for anti-T. gondii IgG and seropositive for anti-T. gondii IgM (low IgG avidity), respectively. Of 20 cord blood samples, 18 were seropositive for T. gondii IgG, whereas all cord blood samples were seronegative for T. gondii IgM. The other six sera were seronegative for T. gondii IgG, whereas three of six sera were seropositive for T. gondii IgM. Furthermore, T. gondii induced an increase in MMP-2 and -9 secretion in the sera of gravidas and umbilical cords. Moreover, MMP-2 and -9 were interacted with fibronectin. We propose that MMP-2 and -9 may be involved in ECM degradation and placental barrier dysfunction, which facilitates T. gondii transmission to the fetus. Future investigations of the effect of MMPs on migration across epithelial and endothelial barriers will be important to establish the mechanism of transit.

Ultrasmooth silver thin film on PEDOT:PSS nucleation layer for extended surface plasmon propagation.

Poly(3,4-ethylene dioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) layers are used as the nucleation (seed) layer to reduce surface roughness of the overlying silver (Ag). The technique leads to ultrasmooth Ag thin films with a minimum surface roughness of 0.8 nm. The mechanism contributing to the improvement is explained on the basis of better wetting of Ag on PEDOT:PSS, and properties of the nucleation layer on the aspects of surface energy, surface adhesive force, and surface morphology influencing Ag wetting and growth pattern are being discussed. The surface plasmon resonance (SPR) shows significant improvement, in terms of the Figure of Merits (FOM), as the surface roughness on Ag films is reduced. A lower light scattering and longer plasmon propagation of maximum 15.3 µm are also realized on a smoother Ag surface. The results indicate great potential on the application of combined PEDOT:PSS/Ag structure as an effective and economically feasible design solution for plasmonic and optical metamaterials devices.

Matrix metalloproteinase-12 leads to elastin degradation in BALB/c mice with eosinophilic meningitis caused by Angiostrongylus cantonensis.

The rat lugworm Angiostrongylus cantonensis can cause eosinophilic meningitis. The purpose of this study was to determine whether matrix metalloproteinase (MMP)-12 and its substrate elastin participate in this inflammatory response. We showed that the MMP-12/tissue inhibitor of metalloproteinase-1 ratio was significantly increased in the CSF of A. cantonensis-infected mice from day 10 p.i., and reached high levels on days 20 and 25 p.i. MMP-12 production was correlated with elastin degradation, eosinophil count, blood-CSF barrier permeability and pathological changes in the subarachnoid space. Also, MMP-12 might contribute to elastin degradation in the meningeal vessel of the subarachnoid space. Simultaneous administration of albendazole and doxycycline significantly reduced the levels of MMP-12, elastin and Evans blue in mice with meningitis. These results imply that MMP-12 contributes to the elastin degradation that occurs in angiostrongyliasis meningitis, and doxycycline can reverse related inflammatory events by inhibition of MMP-12.

Elevated concentrations of matrix metalloproteinase-12 and elastin degradation products in the sera of pregnant women infected with Toxoplasma gondii.

Although the expression of matrix metalloproteinase-12 (MMP-12) appears to be increased in most inflammatory diseases, the role of this enzyme in the pathogenesis of toxoplasmosis in pregnant women, if any, is unknown. In a recent study in Taiwan, the serum concentrations of MMP-12 and its substrate elastin were evaluated in pregnant women with Toxoplasma gondii infection. Compared with the healthy pregnant and non-pregnant women used as controls, the pregnant women with toxoplasmosis had significantly higher serum concentrations of MMP-12 and significantly higher levels of elastin synthesis and degradation. Interaction between MMP-12 and elastin in the serum samples was confirmed by co-immunoprecipitation. It seems possible that MMP-12 may contribute to elastin degradation occurring during the pathogenesis of toxoplasmosis in pregnant women.

FlowCytomix analysis for Toxoplasma gondii infection in pregnant women in central Taiwan.

The study was to determine the seroprevalence of toxoplasmosis in the sera of pregnant women in central Taiwan and to investigate the levels of cytokine in the sera of pregnant women with Toxoplasma gondii infection. The 220 blood samples were collected from pregnant women. The haematological parameters of peripheral blood were analysed by a haematology analyser. Serum samples of the pregnant women were analysed by a commercially available anti-T. gondii IgM/IgG antibody enzyme-linked immunosorbent assay (ELISA) kit and FlowCytomix assays. Six (2.7%) of the sera samples had IgM anti-T. gondii antibodies, and twenty (9.1%) had T. gondii IgG seropositive. All six IgM seropositive samples had low IgG avidity, indicative of acute infection. Total white blood cells and eosinophils were statistically significantly increased (p<0.05) in pregnant women with T. gondii infection, as compared with healthy pregnant women. Th1 cytokines IFN-γ, IL-1ß, IL-2 and IL-12 p70, and Th2 cytokines IL-10 in pregnant women with T. gondii IgM/IgG seropositive were significantly increased (p<0.05), as compared with healthy pregnant women. These results showed that both of Th1 and Th2 cytokines play an important role in the toxoplasmosis of pregnant women.

Contribution of glucocerebrosidase mutation in a large cohort of sporadic Parkinson's disease in Taiwan.

BACKGROUND AND PURPOSE: The association between glucocerebrosidase (GBA) mutations and Parkinson's disease (PD) is attracting increased attention worldwide. In patients of Chinese ethnicity, other than the common L444P mutation, a few mutations have been reported. However, the contribution of GBA to PD can be answered only by a thorough investigation of its mutations in a unique large population. METHODS: We enrolled 1747 participants: 967 PD patients and 780 healthy individuals. We screened entire GBA coding regions and exon-intron boundaries in 30 randomly chosen PD patients, followed by testing five variants (L444P, D409H, R120W, L174P, and Q497R) in all participants. The G2385R and R1628P in LRRK2 had been previously studied in almost all participants. RESULTS: In total, 36 patients (3.72%) carried a heterozygous mutant GBA allele (27 L444P, 7 RecNciI, and 2 D409H). Only two controls (0.26%) carried heterozygous GBA mutation (1 L444P and 1 RecNciI). In PD group, the mean age at onset in carriers was younger than in non-carriers. The difference in percentage of mutation frequencies between patients and controls was highly significant for the L444P mutation (P < 0.0001). One L444P carrier was also associated with LRRK2 G2385R variant, but no atypical Parkinsonism was observed. CONCLUSIONS: The present study ascertains that L444P mutation in GBA gene may contribute to an earlier onset of development of PD in Han/Chinese population. Following LRRK2 variants, GBA is the second most frequent mutations indicated for sporadic PD development in the Han/Chinese population. These GBA carriers are associated with an earlier onset of Parkinsonism.

Induction of plasminogen activators in pregnant women with Toxoplasma gondii infection.

OBJECTIVE: To determine whether plasminogen activators (PAs) are involved in the pathologic process of toxoplasmosis. MATERIALS AND METHODS: Out of 220 pregnant women the study included 26 with a diagnosis of toxoplasmosis: six based on seropositivity for Toxoplasma gondii IgM and 20 based on seropositivity for T. gondii IgG. We measured serum activities and protein levels of PAs by casein zymography and Western blotting, respectively. RESULTS: Serum PAs were higher in healthy pregnant women than in their healthy nonpregnant counterparts. Furthermore, serum PAs were significantly higher in pregnant women infected with T. gondii than in their healthy counterparts. CONCLUSION: PAs participate in the pathogenesis of toxoplasmosis in pregnant women and may be useful markers of T. gondii infection.

Determination of total and non-water soluble iodine in atmospheric aerosols by thermal extraction and spectrometric detection (TESI).

Iodine has recently been of interest in atmospheric chemistry due to its role in tropospheric ozone depletion, modification of the HO/HO(2) ratio and aerosol nucleation. Gas-phase iodine chemistry is tightly coupled to the aerosol phase through heterogeneous reactions, which are dependent on iodine concentrations and speciation in the aerosol. To date, the only method available for total iodine determination in aerosols is collection on filters by impaction and quantification by neutron activation analysis (NAA). NAA is not widely available to all working groups and is costly to commission. Here, we present a method to determine total iodine concentrations in aerosol impact filter samples by combustion of filter sub-samples (approximately 5 cm(2)) at 1,000 degrees C, trapping in deionised water and quantification by UV/Vis spectroscopy. Both quartz and cellulose filters were analysed from four separate sampling campaigns. The method proved to be sensitive (3sigma = 6 ng absolute iodine approximately 3 pmol m(-3)) precise (RSD approximately 5%) and accurate, as determined by external and standard addition calibrations. Total iodine concentrations ranged from 10 pmol m(-3) over the Southern Ocean to 100 pmol m(-3) over the tropical Atlantic, in agreement with previous estimates. The soluble iodine concentration (extracted with water and measured by ICP-MS) was then subtracted from the total iodine to yield non-water-soluble iodine (NSI). The NSI fraction ranged from 20% to 53% of total iodine, and thus can be significant in some cases.

Alterations of myelin proteins in inflammatory demyelination of BALB/c mice caused by Angiostrongylus cantonensis.

Angiostrongylus cantonensis causes eosinophilic meningitis or meningoencephalitis, yet little is known about demyelination caused by this parasite. To define the course of demyelination caused by A. cantonensis, we analyzed the expression of myelin proteins including myelin-associated glycoprotein (MAG), myelin basic protein (MBP), myelin-associated oligodendrocytic basic protein (MOBP), and proteolipid protein (PLP) in brain and cerebrospinal fluid (CSF)-like fluid of infected and uninfected BALB/c mice. In A. cantonensis-infected mice, the expression of MAG, MBP, MOBP, and PLP mRNAs in brain tissue was decreased, while expression of the corresponding proteins was significantly increased in CSF-like fluid. Light microscopy revealed perivascular infiltrates in the brain during meningoencephalitis, suggesting that the cause of demyelination in angiostrongyliasis was immune system attack on the oligodendrocytic myelin sheath and subsequent release of myelin proteins into the CSF. Thus, intracerebral myelin breakdown in angiostrongyliasis may be a response to inflammatory mediators and the cause of increased myelin proteins in the CSF-like fluid.

Differences of proteolytic enzymes and pathological changes in permissive and nonpermissive animal hosts for Angiostrongylus cantonensis infection.

In this study, mice (nonpermissive hosts) infected with Angiostrongylus cantonensis showed significant worm degeneration and eosinophil degranulation, whereas infected rats (permissive hosts) showed lower worm degeneration and eosinophil degranulation. Pathophysiological changes developed to a lesser extent in rat than in the mouse strains. Neurological evaluation of A. cantonensis-infected mice showed mechanical damage caused by worms migrating to the brain. A significant correlation between the proteolytic enzymes, plasminogen activator (PA) and matrix metalloproteinase-9 (MMP-9), and pathological changes was found in hosts with eosinophilic meningitis or meningoencephalitis. Also, the ratio of cerebrospinal fluid (CSF) to serum albumin was consistently increased in hosts with angiostrongyliasis as compared with control. These data clearly indicate that PA and MMP-9 proteolytic enzymes as well as pathological changes are different in permissive and nonpermissive hosts.

Induction of 2',3'-cyclic nucleotide 3'-phosphodiesterase in demyelination of BALB/c mice caused by Angiostrongylus cantonensis.

Angiostrongylus cantonensis causes severe central nervous system (CNS) infection leading to chronic demyelinating disease. The biological role of 2',3'-cyclic nucleotide 3'-phosphohydrolase (CNP) in myelin-related disease requires investigation. CNP expression was investigated in the brain of mice at six time points 5-25 days post-inoculation with A. cantonensis. CNP was measured in brain tissue by quantitative reverse transcription polymerase chain reaction and by western blotting in the cerebrospinal fluid (CSF). The concentration of CNP in the CSF was significantly up-regulated during the severe phase of meningoencephalitis or meningitis as compared with controls. Immunohistochemical labelling localized CNP expression to the cytoplasm of oligodendrocytes. These results suggest that CNP in the CSF from mice with angiostrongylosis is an indicator of myelin destruction. Therefore, measurement of CNP in the CSF of patients with eosinophilic meningitis may be useful in clinical management.

A longitudinal study of Taiwanese sialidosis type 1: an insight into the concept of cherry-red spot myoclonus syndrome.

BACKGROUND AND PURPOSE: Sialidosis type 1 (ST-1) is a neurodegenerative disorder with limited long-term follow-up report. This study is to document the chronological profile of ST-1. METHODS: We perform serial analysis of 17 Taiwanese patients with ST-1 focusing on evolution of clinical features, electrophysiological findings, genetic studies, and neuroimage examinations. RESULTS: All patients had a mutation at 554A-->G in exon 3 of the NEU1 gene causing Ser182Gly substitution. Fifteen patients were homozygous. Two patients were heterozygous with novel mutations, 956C-->T causing Ala319Val in one and 163C-->T causing Gln55stop codon in the other. The neuraminidase activity was markedly decreased in all 11 available patients. Only three patients (17.6%) manifested the macular cherry-red spot. The majority of patients (82.3%) developed full-blown manifestation of myoclonus, ataxia, and seizures within 5 years. Abnormal somatosensory evoked potentials with giant cortical waves were found in all patients. Prolonged P100 peak latency of the visual evoked potentials (VEPs) were found in 16 patients (94.1%) in the early stage even without visual symptoms. CONCLUSION: ST-1 in Taiwanese population illustrates distinct characteristics of phenotype with infrequent cherry-red spot. We suggest to screen the NEU1 mutations in patients presenting action myoclonus with abnormal VEPs, even without macular cherry-red spots.

Comparative efficacies of albendazole and the Chinese herbal medicine long-dan-xie-gan-tan, used alone or in combination, in the treatment of experimental eosinophilic meningitis induced by Angiostrongylus cantonensis.

Angiostrongylus cantonensis, the rat lungworm, is the principal cause of human eosinophilic meningitis or meningoencephalitis world-wide. In the present study, the efficacies of early-stage treatment with the Chinese herbal medicine long-dan-xie-gan-tan (LDXGT) and albendazole, used alone or in combination, were evaluated in BALB/c mice with A. cantonensis-induced dysfunction of the blood-central-nervous-system barrier and eosinophilic meningo-encephalitis. Indicators of the therapeutic effect included worm recovery, histopathological scores for the meningitis, assays of tissue-type plasminogen activator (PA), urokinase-type PA and matrix metalloproteinase-9 (MMP-9) in the brain, the ratio between albumin concentrations in the cerebrospinal fluid (CSF) and serum, and counts of eosinophils in the CSF. Combined treatment with albendazole and LDXGT gave better results than monotherapy based on either drug, apparently inhibiting eosinophilic meningitis via antagonists of the PA/MMP-9 system. LDXGT may have a therapeutic role in reducing inflammatory reaction in the subarachnoid space. Monotherapy with such an anti-inflammatory drug may relieve the symptoms of mild infection and the host's immune responses to A. cantonensis larvae. In severe infection, however, co-therapy with an anthelmintic (to kill the larvae) and an anti-inflammatory agent (to provide symptomatic relief) is probably a better approach. The therapeutic strategy should be tailored to the severity of the illness and the numbers of eosinophils in the CSF.

Changes to plasminogen activators and matrix metalloproteinase-9 in dogs with toxocarosis.

The relationship between proteolytic enzymes and hematological response to infection was studied in five 1-month-old dogs inoculated experimentally with 2000 eggs of Toxocara canis. Moderate leukocytosis and marked eosinophilia occurred 14 days post-infection with T. canis. Plasminogen activators (PAs) and matrix metalloproteinase-9 (MMP-9) activity in serum was significantly different in dogs infected with T. canis, compared with controls. Urokinase-type PA (uPA) activity was positively correlated with eosinophilia, and tissue-type PA (tPA) and MMP-9 activity was negatively correlated with eosinophilia. However, there was no correlation between inflammation and MMP-2. The use of uPA, tPA or MMP-9 proteolytic enzymes as laboratory reference markers for toxocarosis requires further study.