Tissue Cysts Research Articles

Orofacial Cysts: A Single Institution Experience of 85 Cases in Enugu, Nigeria.

Orofacial cysts are pathologic cavities that could be symptomatic and may cause facial disfigurement. The only epidemiologic report of such lesions in Southeast Nigeria studied jaw cysts from 1987 to 1996. New studies reflecting recent research findings and classifications on the subject in Southeast Nigeria are lacking. To determine the prevalence and distribution of orofacial cysts in a tertiary hospital in Enugu, Southeast Nigeria. A 10-year retrospective study of patients with orofacial cysts diagnosed by histology was carried out. Orofacial cysts constitute 9.5% (85) of 897 orofacial lesions identified. The male-to-female gender ratio was 1.2:1. The mean age (± standard deviation) at the onset of the cystic lesion was 28.58 (±16.98) years. Developmental odontogenic cysts 52.9% (45) and salivary cysts 18.8% (16) were the most common group of orofacial cysts. The most prevalent orofacial cysts were odontogenic keratocysts at 25.9% (22), mucoceles 16.5% (14), and dentigerous cysts 14.1% (12). Straw-colored aspirates 34.8% (16) and dark brown aspirates 28.3% (13) were the predominant cystic contents. The mandible 45.9% (39) and maxilla 27.1% (23) were the commonest sites for orofacial cysts, while the lip 9.4% (8) was the most frequent soft tissue site. A significant association exists between anatomical site and cyst type at a 95% confidence interval with P = 0.000, X2 = 247.17. Unilocular radiolucency 62.5% (20) and multilocular radiolucency 34.4% (11) were the most common radiographic features. Developmental odontogenic cysts particularly odontogenic keratocysts were most prevalent while mucocele was the most common soft tissue cyst.

Structural Characterization of Toxoplasma gondii Brain Cysts in a Model of Reactivated Toxoplasmosis Using Computational Image Analysis

Toxoplasma gondii is an obligate intracellular parasite existing in three infectious life stages—tachyzoites, bradyzoites, and sporozoites. Rupture of tissue cysts and re-conversion of bradyzoites to tachyzoites leads to reactivated toxoplasmosis (RT) in an immunocompromised host. The aim of this study was to apply ImageJ software for analysis of T. gondii brain cysts obtained from a newly established in vivo model of RT. Mice chronically infected with T. gondii (BGD1 and BGD26 strains) were treated with cyclophosphamide and hydrocortisone (experimental group—EG) or left untreated as infection controls (ICs). RT in mice was confirmed by qPCR (PCR+); mice remaining chronically infected were PCR−. A total of 90 images of cysts were analyzed for fractal dimension (FD), lacunarity (L), diameter (D), circularity (C), and packing density (PD). Circularity was significantly higher in PCR+ compared to IC mice (p < 0.05 for BGD1, p < 0.001 for the BGD26 strain). A significant negative correlation between D and PD was observed only in IC for the BGD1 strain (ρ = −0.384, p = 0.048), while fractal parameters were stable. Significantly higher D, C, and PD and lower lacunarity, L, were noticed in the BGD1 compared to the more aggressive BGD26 strain. In conclusion, these results demonstrate the complexity of structural alterations of T. gondii cysts in an immunocompromised host and emphasize the application potential of ImageJ in the experimental models of toxoplasmosis.

Immunohistochemical and Histopathological Characterization of Spina Bifida Defect Tissues Removed After Prenatal and Postnatal Surgical Repair

Background: Myelomeningocele or spina bifida is an open neural tube defect that is characterized by protrusion of the meninges and the spinal cord through a deformity in the vertebral arch and spinous process. Myelomeningocele of post-natal tissue is well described; however, pre-natal tissue of this defect has no known previous histologic characterization. We compared the histology of different forms of pre-natal myelomeningocele and post-natal myelomeningocele tissue obtained via prenatal intrauterine and postnatal surgical repairs. Methods: Pre-and post-natal tissues from spina bifida repair surgeries were obtained from lipomyelomeningocele, myeloschisis, and myelomeningocele spina bifida defects. Tissue samples were processed for H&E and immunohistochemical staining (KRT14 and p63) to assess epidermal and dermal development. Results: Prenatal skin near the defect site develops with normal epidermal, dermal, and adnexal structures. Within the grossly cystic specimens, histology shows highly dense fibrous connective tissue with complete absence of a normal epidermal development with a lack of p63 and KRT14 expression. Conclusion: Tissues harvested from prenatal and postnatal spina bifida repair surgeries appear as normal skin near the defect site. However, cystic tissues consist of highly dense fibrous connective tissue with complete absence of normal epidermal development.

Comparative evaluation of silver nanoparticles and human platelet rich-plasma versus traditional therapy in the treatment of murine chronic toxoplasmosis.

Toxoplasmosis is a worldwide parasitic disease infecting about one-third of the human population. At present, licensed medications are incapable of curing human chronic infection. The present work aimed to evaluate for the first time the combination between (spiramycin and human platelet rich plasma), in addition to (spiramycin and silver-nanoparticles) in treating murine experimental toxoplasmosis using parasitological, biochemical, histopathological and immunohistochemical studies. Seventy-seven Swiss albino male mice divided into seven groups according to the treatment used as follows: (GI): control negative; (GII): control infected; (GIII): spiramycin; (GIV): Silver nanoparticles (AgNPs); (GV): Human platelet-rich plasma (HPRP); (GVI): combined spiramycin and AgNPs; (GVII): combined spiramycin and HPRP. Obtained results demonstrated that (spiramycin and AgNPs) treated group showed significant reduction of T. gondii tissue cysts number, the lowest level of serum malondialdehyde, remarkable improvement in pathological changes in different tissues of mice e.g. brain and liver and weak expression of EGFR in brain tissues of mice compared to control infected group. Moreover, AgNPs administered alone produced minimal anti-Toxoplasma results, whereas their combination with spiramycin exhibited significant therapeutic efficacy. In conclusion, combination therapy of spiramycin and AgNPs may represent a unique possible adjuvant therapy for reducing the pathogenic, toxic, and inflammatory consequences of toxoplasmosis on the brain and liver tissues in immunocompetent mice, and the expression of EGFR in brain tissues of mice is a good tool for evaluating the therapeutic improvement of murine toxoplasmosis.

Direct evidence of cheetah (Acinonyx jubatus) as intermediate host of Toxoplasma gondii through isolation of viable strains

Toxoplasma gondii causes lifelong infection in most definitive and intermediate hosts. Clinical cases of toxoplasmosis in captive cheetahs have been reported. However, there are few reports of viable T. gondii strains isolated from cheetahs. Here, T. gondii infection was investigated using molecular and serological assays in cheetahs from China. Modified agglutination test (MAT) (cut-off: 1:25) indicated that all six examined cheetahs (n = 6) showed T. gondii antibodies. Toxoplasma gondii DNA was detected in three out of five cheetahs. Two viable T. gondii strains were isolated from the striated muscles of two cheetahs using mice bioassay. They were designated as TgCheetahCHn1 and TgCheetahCHn2. Genetic characterization of DNA derived from tachyzoites was performed using RFLP-PCR of 10 markers. Toxoplasma gondii TgCheetahCHn1 is ToxoDB PCR-RFLP genotype #319, and the alleles of ROP18/ROP5 types were 3/7. TgCheetahCHn2 is ToxoDB genotype #9, and the alleles of ROP18/ROP5 were 3/6. The average survival time of TgCheetahCHn1-infected Swiss mice was 22 ± 1 days (n = 23), and the mice did not have detectable T. gondii-specific antibodies until 117 ± 30 days post-inoculation (n = 8), therefore, TgCheetahCHn1 had intermediate virulence. TgCheetahCHn2 was avirulent for Swiss mice. Few brain tissue cysts (0–50) were observed in the mice inoculated with TgCheetahCHn1 or TgCheetahCHn2. The results provide direct evidence of cheetah as intermediate host of T. gondii.

A Comprehensive Review of Toxoplasmosis: Serious Threat to Human Health

Toxoplasmosis is a parasitic disease caused by Toxoplasma gondii. Despite infecting a major fraction of the global population, T. gondii rarely results in clinically significant disease. Cats are the only known definitive host for this parasite, which sheds millions of oocysts in its feces every day, which then sporulate and become infective in the environment. This comprehensive review article aims to explain the etiology, pathogenesis, epidemiology, transmission, clinical symptoms, diagnosis, risk factors, public health importance, economic effect, treatment, and prevention of toxoplasmosis. A search for various publications in English with the criteria of reviewing articles explaining toxoplasmosis was carried out. T. gondii reproduces through two life cycles, namely the sexual cycle and the asexual cycle. In general, consuming parasite cysts in tainted food or water is how humans and other warm-blooded animals become infected with T. gondii. Nearly every region of the world has reported incidences of toxoplasmosis in humans, and around one-third of people are susceptible to latent infection. According to the reports, the main ways through which diseases spread are by water, tainted food, eating tissue cysts or oocysts, and congenital transmission. Infected individuals may experience asymptomatic cervical lymphadenopathy during an acute systemic infection. Diagnostic evaluation is very important for early detection, prevention of transmission, and as a reference for treatment options for infected pregnant women. Consuming undercooked meat is traditionally seen as a significant risk factor for developing toxoplasmosis. The impact of toxoplasmosis is very significant in humans because it causes abortion and disease in newborns, resulting in serious economic losses. To treat toxoplasmosis, dihydropteroate synthetase and dihydrofolate reductase inhibitors are advised. Toxoplasma transmission to humans can be avoided by thoroughly washing your hands with soap after handling meat, poultry, or shellfish.

Investigation of the effects of Toxoplasma gondii on behavioral and molecular mechanism in bradyzoite stage

Toxoplasma gondii is a single-celled parasite that causes a disease called toxoplasmosis. It can reach the central nervous system, but the mechanism of T. gondii disrupting the functioning of these brain regions occurs in bradyzoite stage of parasite, causing brain damage by forming tissue cysts in brain. In our study, the effects of T. gondii on locomotor activity, anxiety, learning and memory, and norepinephrine (NE), levodopa (L-DOPA), dopamine (DA) and 3,4-D-dihydroxyphenylacetic acid (DOPAC) catecholamines in amygdala, striatum, prefrontal cortex and hippocampus regions of the brain were investigated in bradyzoite stage. Twenty male Albino mice Mus musculus, 4–5 weeks old, weighing 20–25 g, were used. T. gondii inoculated to mice intraperitonealy with 48–50-hour passages of T. gondii RH Ankara strain. For intraperitoneal inoculation of mice 5x104 tachyzoites per mouse. No inoculation was made in control group (n: 20). Locomotor activity behavior in open field test (OFT), anxious behavior in elevated plus maze (EPM), and learning behavior in novel object recognition (NOR) tests were evaluated. NE, L-DOPA, DA and DOPAC were measured by HPLC in brain tissues of amygdala, striatum, prefrontal cortex and hippocampus. A decrease was observed in the locomotor activity, anxiety and learning values of the T. gondii group compared to the control group (p < 0.05). The heighten in NE and L-DOPA levels in amygdala tissue of T. gondii group compared to control group, an elevation in NE, L-DOPA, DA and DOPAC levels in striatum tissue, and an increase in levels of NE in prefrontal cortex tissue were detected in monoamine results. In hippocampus tissue, an increase was observed in DA levels, while a decrease was observed in NE, L-DOPA and DOPAC levels. In our study, it has been shown that T. gondii in bradyzoite stage reduces locomotor activity, causes learning and memory impairment, and has anxiogenic effects.

The role of species ecology in predicting Toxoplasma gondii prevalence in wild and domesticated mammals globally.

Macroecological approaches can provide valuable insight into the epidemiology of globally distributed, multi-host pathogens. Toxoplasma gondii is a protozoan that infects any warm-blooded animal, including humans, in almost every habitat worldwide. Toxoplasma gondii infects its hosts through oocysts in the environment, carnivory of tissue cysts within intermediate host prey and vertical transmission. These routes of infection enable specific predictions regarding the ecological and life history traits that should predispose specific taxa to higher exposure and, thus infection rates of T. gondii. Using T. gondii prevalence data compiled from 485 studies representing 533 free-ranging wild mammalian species, we examined how ecological (habitat type, trophic level) and life history (longevity, vagility, gestation duration and torpor) traits influence T. gondii infection globally. We also compared T. gondii prevalence between wild and domesticated species from the same taxonomic families using data compiled from 540 studies of domestic cattle, sheep, and pigs. Across free-ranging wildlife, we found the average T. gondii prevalence was 22%, which is comparable to the global human estimate. Among ecological guilds, terrestrial species had lower T. gondii prevalence than aquatic species, with freshwater aquatic taxa having an increased prevalence compared to marine aquatic species. Dietary niches were also influential, with carnivores having an increased risk compared to other trophic feeding groups that have reduced tissue cyst exposure in their diet. With respect to influential life history traits, we found that more vagile wildlife species had higher T. gondii infection rates, perhaps because of the higher cumulative risk of infection during movement through areas with varying T. gondii environmental loads. Domestic farmed species had a higher T. gondii prevalence compared to free-ranging confamilial wildlife species. Through a macroecological approach, we determined the relative significance of transmission routes of a generalist pathogen, demonstrating an increased infection risk for aquatic and carnivorous species and highlighting the importance of preventing pathogen pollution into aquatic environments. Toxoplasma gondii is increasingly understood to be primarily an anthropogenically-associated pathogen whose dissemination is enhanced by ecosystem degradation and human subsidisation of free-roaming domestic cats. Adopting an ecosystem restoration approach to reduce one of the world's most common parasites would synergistically contribute to other initiatives in conservation, feline and wildlife welfare, climate change, food security and public health.

Detection of Toxoplasma gondii in artisanal salted meat products sold in street markets of the Ilhéus-Itabuna microregion.

This study aimed to detect Toxoplasma gondii in artisanal salted meat products sold in street markets in the Ilhéus-Itabuna microregion and to assess the salt concentration used in their preparation and its influence on the parasite's viability. A total of 125 samples of various artisanal meat products sold in street markets located in the Ilhéus-Itabuna microregion were collected during 2021. Serological analysis using indirect hemagglutination (HAI) and molecular analysis (PCR) were performed on these samples to detect the presence of the parasite. Möhr's method was utilized to determine the sodium chloride concentration in the samples. Of all samples, 21 were subjected to a bioassay in albino mice to verify the viability of possible tissue cysts. Among the 125 meat products, 10 (8%) tested positive in the serological analysis including four cured pork sausages, five beef sun-dried meats, and one mixed fresh sausage (pork and chicken). None of 125 samples tested positive in the molecular analysis. On bioassay, all mice tested negative for the presence of the parasite. The NaCl concentration in the positive samples ranged from 2.9% to 8%. The results demonstrated that the salt concentration in the collected samples was sufficient to inactivate the parasite T. gondii.

Experimental Protocol to Toxoplasma gondii Detection in Fresh Goat Milk.

Toxoplasma gondii is a zoonotic parasite with global distribution capable of infecting homeothermic animals. Transmission of protozoan to humans includes ingestion of water and raw food contaminated with sporulated oocysts, ingestion of raw or undercooked meat with tissue cysts, and tachyzoites' transplacental transmission. Fresh goat milk intake has already been linked to human toxoplasmosis outbreaks, but little is known about the infectious potential of this biological sample. Accordingly, the aim of the present study is to assess the survival and infectivity of T. gondii tachyzoites in fresh goat milk samples through an experimental protocol to detect this parasite via bioassay carried out with a murine model, DNA amplification, and serology. Swiss Webster mice were inoculated with fresh goat milk samples contaminated with different T. gondii RH strain tachyzoite concentrations per milliliter and stored for different refrigeration times. Animals showing clinical signs compatible to toxoplasmosis were euthanized. Milk samples contaminated with high parasitic loads and kept for a shorter refrigeration time were the most lethal ones. No significant differences were observed between mean death rates recorded for different goat milk contamination concentrations (p = 0.1888), and for the refrigeration time, contaminated milk samples were kept under (p = 0.9440). T. gondii DNA was amplified in all contaminated milk samples, but only one of the surviving mice was serologically positive. Results of the present study have shown T. gondii survival and infectivity in fresh goat milk samples, and it highlights its significant risk for public health. Therefore, molecular methods must be the tests of choice when milk samples are used to assess infection caused by protozoan in goats' dairy products.

Generation of Mature Toxoplasma gondii Bradyzoites in Human Immortalized Myogenic KD3 Cells.

Toxoplasma gondii is a zoonotic protozoan parasite and one of the most successful foodborne pathogens. Upon infection and dissemination, the parasites convert into the persisting, chronic form called bradyzoites, which reside within cysts in muscle and brain tissue. Despite their importance, bradyzoites remain difficult to investigate directly, owing to limited in vitro models. In addition, the need for new drugs targeting the chronic stage, which is underlined by the lack of eradicating treatment options, remains difficult to address since in vitro access to drug-tolerant bradyzoites remains limited. We recently published the use of a human myotube-based bradyzoite cell culture system and demonstrated its applicability to investigate the biology of T. gondii bradyzoites. Encysted parasites can be functionally matured during long-term cultivation in these immortalized cells and possess many in vivo-like features, including pepsin resistance, oral infectivity, and antifolate resistance. In addition, the system is scalable, enabling experimental approaches that rely on large numbers, such as metabolomics. In short, we detail the cultivation of terminally differentiated human myotubes and their subsequent infection with tachyzoites, which then mature to encysted bradyzoites within four weeks at ambient CO2 levels. We also discuss critical aspects of the procedure and suggest improvements. Key features • This protocol describes a scalable human myotube-based in vitro system capable of generating encysted bradyzoites featuring in vivo hallmarks. • Bradyzoite differentiation is facilitated through CO2 depletion but without additional artificial stress factors like alkaline pH. • Functional maturation occurs over four weeks.

Minimally invasive surgical treatment of extramedullary tumors at the level of craniovertebral junction: experience of the Burdenko Neurosurgical Center

To describe own experience of treating patients with extramedullary tumors at the level of craniovertebral junction using minimally invasive surgical approaches. The study included 29 patients who underwent minimally invasive microsurgical resection of extramedullary tumors at the level of craniovertebral junction. We analyzed the main clinical and surgical parameters. Gross total resection was achieved in most patients with high degree of safety. Two patients required redo surgery due to CSF leakage and soft tissue cyst. Mean length of hospital-stay was 7 days. VAS score of pain syndrome at discharge was 2 points and 0 points after 3 months. No significant differences in neurophysiological monitoring indicators were observed (p=0.76). Minimally invasive posterior approaches to extramedullary tumors at the level of craniovertebral junction can significantly reduce surgical trauma with equal extent of resection.

Інтегральний аналіз клінічних та рентген- антропометричних предикторів тонкого фенотипу тканин пародонту як фактора ризику пародонтальних ускладнень ортодонтичного лікування

Resume: In the article, it was carried out a study of the most clinical predictors of the thin biotype of periodontal tissue, as a consequence of healing in predicting the possible complications of orthodontic treatment. And to itself: I have a mucus alveolar growth with zones of ischemia; small child of an empty company; prominence of roots, lower frontal teeth; short lips ties and tongue tie; manifestations of additional folds of vestibule of the mouth; injection of blood vessels on the alveolar ridge and on the inner surface of the lips and cheek; sharply folded alveolar ridge; change in the height of the interdental papillae and change in the shape of their tops; the presence of wide and narrow recesses is clear. Statistically priming of thin and small X-ray anthropometric predictors of thin biotype of periodontal tissues: thin and long roots of lower cuts; half-moon-like tops of the roots of the cuts and the cleavages of the lower slit; large drawing of trabeculae of spongy cystic tissue; straight, or so, that the roots of the first permanent molars of the lower fissure diverge; a sharp deficit in the height of the body of the lower crack, especially in the vineyards. Key words: periodontal tissue, orthodontic treatment, periodontal tissue biotype, orthopantomography

A Current Update on Neospora caninum

Neospora caninum is an apicomplexan protozoan parasite, which was first identified as a cause of canine paralysis. This parasite is now recognized as an important cause of reproductive problems and abortion in cows. Prior to its first recognition in Norwegian dogs in 1984 and consequential classification as a distinct species in 1988, many N. caninum infections were misdiagnosed as toxoplasmosis. Neospora has a complex life cycle and transmission routes. Carnivores probably become infected by ingesting tissue cysts containing bradyzoites, and herbivores probably become infected by the ingestion of food or drinking water contaminated by N. caninum sporulated oocysts from the feces of carnivores. During pregnancy it becomes activated again, breaks out of the tissue cysts and migrates to the placenta. Infection of the placenta may lead to abortion, which would provide a source of contaminated meat for definitive hosts. In addition, the parasite may be transmitted to the foetus, which can lead to the birth of congenitally and persistently infected calves. Most reports of neosporosis outbreaks have occurred in cows that are intensively managed; thus, the incidence increases as larger cattle farms with intensive feeding practices become more common. Immunofluorescent antibody test (IFAT) and indirect enzyme-linked immunosorbent assay (ELISA) and histopathology of fetus are used for diagnosis. At present, there is no effective treatment for bovine neosporosis. Control of abortion in infected cattle depends on saving food and water sources and the grazing environment from feces of carnivores, properly discarding aborted feoutus and control of dog.

Functional analyses of Toxoplasma gondii dihydroorotase reveal a promising anti-parasitic target.

Toxoplasma gondii relies heavily on the de novo pyrimidine biosynthesis pathway for fueling the high uridine-5'-monophosphate (UMP) demand during parasite growth. The third step of de novo pyrimidine biosynthesis is catalyzed by dihydroorotase (DHO), a metalloenzyme that catalyzes the reversible condensation of carbamoyl aspartate to dihydroorotate. Here, functional analyses of TgDHO reveal that tachyzoites lacking DHO are impaired in overall growth due to decreased levels of UMP, and the noticeably growth restriction could be partially rescued after supplementation with uracil or high concentrations of L-dihydroorotate invitro. When pyrimidine salvage pathway is disrupted, both DHOH35A and DHOD284E mutant strains proliferated much slower than DHO-expressing parasites, suggesting an essential role of both TgDHO His35 and Asp284 residues in parasite growth. Additionally, DHO deletion causes the limitation of bradyzoite growth under the condition of uracil supplementation or uracil deprivation. During the infection in mice, the DHO-deficient parasites are avirulent, despite the generation of smaller tissue cysts. The results reveal that TgDHO contributes to parasite growth both invitro and invivo. The significantly differences between TgDHO and mammalian DHO reflect that DHO can be exploited to produce specific inhibitors targeting apicomplexan parasites. Moreover, potential DHO inhibitors exert beneficial effects on enzymatic activity of TgDHO and T. gondii growth invitro. In conclusion, these data highlight the important role of TgDHO in parasite growth and reveal that it is a promising anti-parasitic target for future control of toxoplasmosis.

Frequency of Cysts by Immunofluorescence Assay in Human Brain Tissue of Suicide, Traffic Accident and Homicide Decedents

BACKGROUND: Several studies link toxoplasmosis with neuropsychiatric disorders. There are no previous reports of the frequency of the presence of parasite tissue cysts in autopsy cases from violent death or how is the distribution of frequency according to brain regions related with behavior (amygdala or hippocampus). The immune fluorescent antibody technique (IFAT) detects specific target antigens that allow the observation of bradyzoites within tissue cysts. We describe the frequency of tissue cysts using the IFAT detection in human brain tissue samples from immunocompetent persons deceased by suicide, traffic accidents and homicide. METHODS: 21 brains from the National Institute of Legal Medicine and Forensic Sciences chapter “Eje Cafetero” (including cities of Armenia, Pereira, and Manizales) of violently deceased (which includes suicide, traffic accidents and homicide) persons were obtained, subsequently sections of the amygdala and hippocampus areas were processed in paraffin and thick sections were cut from paraffin blocks and mounted on slides by means of the IFAT, by using specific monoclonal anti BAG1 protein of the bradyzoite. Serum samples from the decedents were also examined for the presence of IgG and IgM antibodies to establish the existence of a previous infection. Data such as age, gender, sociodemographic data, and type of death were also obtained. Evaluation of the differences in the percentage of positivity according to the cause of death were assayed by using the Fisher exact test. RESULTS: Two decedents (9.5%) were female and 19 (90.4%) were male. The age ranged from 14 to 65 years; most completed or were in high school level of education. By city, 9 were from Armenia (42.8%%) and 12 from Manizales (57.1%). By type of death, 11 samples (52.3%) were victims of homicide, 9 samples (42.8%) were suicide, and one sample (4.7%) was a traffic accident. We identified tissue cysts containing the bradyzoites in two cases in amygdala (9.5%), in amygdala and hippocampus in tree (14.2%), and one case only in hippocampus (4.7%). In total we have six of 23 (26%) were positive for cysts in the brain. No statistically significant differences were found between groups in the percent of positivity. After counting we found a mean 1,3 ± 0,4 cysts by 20 microscopy fields of positive brain tissue examined. We found one of 21 positives for IgG antibodies in blood (47%). Within six cases with positive by IFAT in brain tissue five were also positive in antibodies (83%) only one case was negative for antibodies. CONCLUSION: The presence of bradyzoite was demonstrated in brain tissue samples from immunocompetent patients who suffered a violent death in the cities of Armenia and Manizales, Colombia. The results suggest that the bradyzoite after infection is permanently localized in brain tissue. A higher prevalence of bradyzoite parasites is observed in amygdala samples, an important region for behavior control.

Toxoplasma gondii seroprevalence in reindeer (Rangifer tarandus tarandus L.) in northern Sweden: a cross-sectional study from 2014

BackgroundToxoplasma gondii is a parasitic protozoan that can infect a wide range of warm-blooded animals, including humans. The infection with T. gondii, is of particular concern due to its potential impact on human and animal health. In Sweden, semi-domesticated reindeer (Rangifer tarandus tarandus L.) is an important species both economically and culturally, but susceptibility to Toxoplasma infection and seroprevalence in reindeer herds remain relatively understudied.ResultsA total of 528 reindeer, sampled at two slaughterhouses in Sweden in 2014, were investigated for antibodies to T. gondii. Specific antibodies to T. gondii were found in 5 of 209 (2.3%) tested adult reindeer and in 6 of 308 (1.9%) tested calves, giving an apparent total prevalence of 2.1% (95% confidence interval 1.1–3.8%). None of four putative risk factors studied (sex, age, type of grazing area, county) were statistically associated with T. gondii seroprevalence.ConclusionsSwedish semi-domesticated reindeer are exposed to T. gondii and may harbour infectious tissue cysts. To mitigate the risk of T. gondii infection in consumers, reindeer meat should be frozen or cooked thoroughly before consumption. The global climate change may influence the seroprevalence and possible associated risk factors for T. gondii in reindeer. To be able to manage the risk and get better advice to the consumers there is a need for further investigations covering the whole spectra of herding conditions for reindeer.

Sarcocystis in horses from Rio Grande do Sul, Brazil: Molecular identification of Sarcocystis bertrami and Sarcocystis neurona in muscle tissues

Horses are intermediate hosts of Sarcocystis spp. capable of forming cysts in their musculature. This study aimed to detect sarcocysts and investigate the presence of nucleic acids from Sarcocystis spp. in samples of striated muscles from horses in the State of Rio Grande do Sul, Brazil, necropsied at the Veterinary Pathology Laboratory of the Federal University of Santa Maria. A total of 108 samples were collected from 24 horses and examined through direct examination. Microscopic tissue cysts were observed in three samples: tongue (2) and esophagus (1) from two animals. Extractions were performed on the found cysts and tissues, even though sarcocystosis detection was not present. DNA samples were subjected to Nested-PCR using Tg18s primers, and the amplified products were subjected to Restriction Fragment Length Polymorphism (RFLP) using DdeI and HpaII enzymes. DNA belonging to Sarcocystis spp. was amplified in tissues from 91.7% (22/24) of the equines, and 67.6% (73/108) of the samples tested positive in the Nested-PCR reaction. The tissues with the highest detection frequency were: diaphragm 92.3% (12/13), gluteal muscle 77.2% (17/22), and esophagus 66.7% (4/6). In RFLP, Sarcocystis spp. was detected in 21 tissues from 11/22 equines, and cysts, identified through nucleotide sequencing, were determined to be S. bertrami. S. neurona was identified in 11 samples from 7/22 animals, with co-infection detected in 5/22 cases. The high detection rate indicates a concerning circulation of the protozoan, particularly the zoonotic S. bertrami found in all tissues, which are commonly exported for human consumption.

Cleavage of periostin by MMP9 protects mice from kidney cystic disease.

The matrix metalloproteinase MMP9 influences cellular morphology and function, and plays important roles in organogenesis and disease. It exerts both protective and deleterious effects in renal pathology, depending upon its specific substrates. To explore new functions for MMP9 in kidney cysts formation and disease progression, we generated a mouse model by breeding juvenile cystic kidney (jck) mice with MMP9 deficient mice. Specifically, we provide evidence that MMP9 is overexpressed in cystic tissue where its enzymatic activity is increased 7-fold. MMP9 deficiency in cystic kidney worsen cystic kidney diseases by decreasing renal function, favoring cyst expansion and fibrosis. In addition, we find that periostin is a new critical substrate for MMP9 and in its absence periostin accumulates in cystic lining cells. As periostin promotes renal cyst growth and interstitial fibrosis in polycystic kidney diseases, we propose that the control of periostin by MMP9 and its associated intracellular signaling pathways including integrins, integrin-linked kinase and focal adhesion kinase confers to MMP9 a protective effect on the severity of the disease.

Isolation and Characterization of a Viable Toxoplasma gondii from Captive Caracal (Caracal caracal).

Toxoplasma gondii is a widespread protozoan parasite that infects most warm-blooded animals, and felids can serve as intermediate and definitive hosts. Pathological diagnosis and serological and etiological investigations were conducted on a captive caracal (Caracal caracal) carcass collected from China in 2022. Pathological diagnosis revealed that cardiac insufficiency, pulmonary edema, hepatic failure, and renal insufficiency were the causes of the caracal's death. A modified agglutination test (cut-off: 1:25) revealed that IgG antibodies against T. gondii were present in the myocardium juice (1:1600), ascitic fluid (1:3200), and hydropericardium (1:800). A viable T. gondii (TgCaracalCHn2) strain was isolated from the tissue samples (heart, brain, spleen, and skeletal muscle) of this caracal using a mouse bioassay. The genotype of TgCaracalCHn2 was ToxoDB#5 (Type II variant), as determined via RFLP-PCR. The strain was avirulent in Swiss mice and matched the prediction of ROP18 and ROP5 gene alleles of TgCaracalCHn2 (2/2). Mild tissue cysts (203 ± 265) were observed in mice brains after inoculation with TgCaracalCHn2 tachyzoites. ToxoDB#5 is the dominant genotype in North American wildlife, and this is the first documented isolation of T. gondii ToxoDB#5 from China. This indicates that caracal plays an important role in the transmission of this T. gondii genotype.