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Abstract Wild boar (Sus scrofa L.) is one of the large mammals most spread worldwide, highly adaptable, and its population rapidly increased in many areas in Europe, including Italy, where Tuscany is considered particularly suitable for wild boar. Wild boars are potential hosts for different etiological agents, such as Brucella spp., Leptospira spp. and Pseudorabies virus and they can contribute to maintain and/or to disseminate some bacterial or viral pathogens to humans and domestic animals, above all-in free-range farms. In order to identify hypothetical genomic regions associated with these infection diseases, 96 samples of wild boars hunted in Tuscany during the 2018–2019 and 2019–2020 hunting seasons were considered. Diagnosis was achieved by serological tests and 42 Pseudorabies, 31 Leptospira and 15 Brucella positive animals were identified. All animals were genotyped with Geneseek Genomic Profiler Porcine HD (70 k) and a genome-wide scan was then performed. Significant markers were highlighted for Pseudorabies (two SNPs), Brucella (seven SNPs), and Leptospira (four SNPs) and they were located within, or nearby, 29 annotated genes on chromosome 6, 9, 12, 13, 14 and 18. Eight genes are implicated in viral (SEC14L1, JMJD6, SRSF2, TMPRSS2, MX1, MX2) or bacterial (COL8A1, SPIRE1) infections, seven genes (MFSD11, METTL23, CTTNBP2, BACE2, IMPA2, MPPE1 and GNAL) are involved in mental disorders and one gene (MGAT5B) is related to the Golgi complex. Results presented here provide interesting starting points for future research, validation studies and fine mapping of candidate genes involved in bacterial and viral infections in wild boar.

Une entérobactérie ayant les caractéristiques d'une salmonelle est isolée en culture pure des prélèvements provenant d'un taurillon de race Indu-Brasil, mort quinze jours après le déclenchement d'une entérite aiguë. L'identification révèle qu'il s'agit de Salmonella nairobi. La seule salmonelle isolée jusque là dans cette région était S. dublin. Il s'agit du premier isolement de S. nairobi au Zaïre et du second isolement en Afrique à partir de l'espèce bovine

Introduction: The world population is aging. By 2050, the global population aged over 65 years will have doubled, leading to big societal challenges for ensuring healthy, independent, and productive lives for older people. Thus, innovative local and national initiatives for e-health services are growing in an attempt to overcome such problems., Methods: We examined the effects of a telehealth system, i.e. tele-monitoring of vital parameters and neurological/psychological tele-counseling, within a family-centred service provided by a local day centre. We evaluated the clinical and neurobehavioral symptoms of 18 elderly patients (aged 65 years and over) and the care burden of their 20 caregivers, besides the usability of the tool., Results: The one-way repeated analysis revealed a significant worsening in daily living activities (p < 0.01 and p = 0.02, respectively for Activities of Daily Living (ADL) and Independent IADL (IADL)) versus a significant improvement of the patients' psychiatric condition (p < 0.001), besides a significant gradual reduction of the caregivers burden (p < 0.001). Health status perception increased through time (from an average score of 5.67 ± 1.08 at baseline to 7.72 ± 1.32 at the end of the study)., Discussion: It appears that a telehealth system integrated in a local health care service may significantly improve elderly persons' behaviour, and also reduce the caregivers' burden., (© The Author(s) 2015.)

Gait abnormalities following neurological disorders are often disabling, negatively affecting patients' quality of life. Therefore, regaining of walking is considered one of the primary objectives of the rehabilitation process. To overcome problems related to conventional physical therapy, in the last years there has been an intense technological development of robotic devices, and robotic rehabilitation has proved to play a major role in improving one's ability to walk. The robotic rehabilitation systems can be classified into stationary and overground walking systems, and several studies have demonstrated their usefulness in patients after severe acquired brain injury, spinal cord injury and other neurological diseases, including Parkinson's disease, multiple sclerosis and cerebral palsy. In this review, we want to highlight which are the most widely used devices today for gait neurological rehabilitation, focusing on their functioning, effectiveness and challenges. Novel and promising rehabilitation tools, including the use of virtual reality, are also discussed.

Brain computed tomography (CT) is useful diagnostic tool for the evaluation of several neurological disorders due to its accuracy, reliability, safety and wide availability. In this field, a potentially interesting research topic is the automatic segmentation and recognition of medical regions of interest (ROIs). Herein, we propose a novel automated method, based on the use of the active appearance model (AAM) for the segmentation of brain matter in CT images to assist radiologists in the evaluation of the images. The method described, that was applied to 54 CT images coming from a sample of outpatients affected by cognitive impairment, enabled us to obtain the generation of a model overlapping with the original image with quite good precision. Since CT neuroimaging is in widespread use for detecting neurological disease, including neurodegenerative conditions, the development of automated tools enabling technicians and physicians to reduce working time and reach a more accurate diagnosis is needed., (© The Author(s) 2015.)

Although gait abnormality is one of the most disabling events following stroke, cognitive, and psychological impairments can be devastating. The Lokomat is a robotic that has been used widely for gait rehabilitation in several movement disorders, especially in the acute and subacute phases. The aim of this study was to evaluate the effectiveness of gait robotic rehabilitation in patients affected by chronic stroke. Psychological impact was also taken into consideration. Thirty patients (13 women and 17 men) affected by chronic stroke entered the study. All participants underwent neurological examination with respect to ambulation, Ashworth, Functional Independence Measure, and Tinetti scales to assess their physical status, and Hamilton Rating Scale for Depression, Psychological General Well-being Index, and Coping Orientation to Problem Experienced to evaluate the Lokomat-related psychological impact before and after either a conventional treatment or the robotic training. During each rehabilitation period (separated by a no-treatment period), patients underwent a total of 40 1 h training sessions (i.e. five times a week for 8 weeks). After the conventional treatment, the patients did not achieve a significant improvement in the functional status, except balance (P<0.001) and walking ability (P<0.01), as per the Tinetti scale. Indeed, after the robotic rehabilitation, significant improvements were detected in almost all the motor and psychological scales that we investigated, particularly for Psychological General Well-being Index and Coping Orientation to Problem Experienced. Manual and robotic-assisted body weight-supported treadmill training optimizes the sensory inputs relevant to step training, repeated practice, as well as neuroplasticity. Several controlled trials have shown a superior effect of Lokomat treatment in stroke patients' walking ability and velocity in particular. Therefore, our preliminary results proved that active robotic training not only facilitates gait and physical function but also the psychological status, even in patients affected by chronic stroke.

Early detection of dementia can be useful to delay progression of the disease and to raise awareness of the condition. Alterations in temporal and spatial EEG markers have been found in patients with Alzheimer's disease (AD) and mild cognitive impairment (MCI). Herein, we propose an automatic recognition method of cognitive impairment evaluation based on EEG analysis using an artificial neural network (ANN) combined with a genetic algorithm (GA). The EEGs of 43 AD and MCI patients (aged between 62 and 88 years) were recorded, analyzed and correlated with their MMSE scores. Quantitative EEGs were calculated using discrete wavelet transform. The data obtained were analyzed by the means of the combined use of ANN and GA to determine the degree of cognitive impairment. The good recognition rate of ANN fed with these inputs suggests that the combined GA/ANN approach may be useful for early detection of AD and could be a valuable tool to support physicians in clinical practice.

Objective: Aim of this study was to evaluate the effects of an emerging rehabilitative tool ("Power-AFA" - software) in the recovery of a patient with chronic non-fluent aphasia., Material and Methods: A 56-year-old woman, affected by post-stroke severe expressive aphasia, underwent two different intensive rehabilitation trainings, including either standard language rehabilitation alone or a proper PC based speech training in addition to conventional treatment. We evaluated her cognitive and psychological profile in two separate sessions, before and after the two different trainings, by using a proper psychometric battery, to assess cognitive status, language abilities, and to estimate the presence of mood alterations and coping strategies. The overall PC-program was articulated in 6 sessions/weekly for 3 months., Results: Only at the end of the PC-training, we observed an important improvement in peculiar cognitive domains (attention and memory functions), in denomination, in verbal understanding ability, in written, in communication skills as well as an optimization of the mood and coping styles., Conclusions: Computer-based cognitive and language rehabilitation, using proper and dedicated software, may be a valuable tool in improving either communication or cognitive skills in patient affected by aphasia, even in the chronic state.

Background/aims: The purpose of the present study was to characterize the role of Na+, pH and cellular swelling in the pathogenesis of hypoxic injury to rat livers., Methods and Results: When livers were perfused with hypoxic Krebs-Henseleit bicarbonate buffer (KHB) containing 143 mM Na+, release of LDH began after 30 min and was maximal after 60 min. In livers perfused with choline-substituted low-Na+ KHB (25 mM Na+), LDH release began after 60 min and peaked after 120 min or longer. Supplementation of KHB with mannitol, a permeant sugar with antioxidant properties, suppressed LDH release, whereas sucrose, an impermeant disaccharide, did not afford protection. At the end of hypoxic perfusions with KHB and low-Na+ KHB, liver weight was not different, whereas mannitol but not sucrose increased liver weight after hypoxia. At pH 7.4, monensin, a Na+-H+ ionophore, reversed protection against hypoxia by low-Na+ KHB (10 mM Na+) but had no effect at pH 6.8. As measured directly by confocal microscopy of biscarboxyethylcarboxyfluorescein fluorescence, pH was lower during perfusion with low-Na+ KHB than KHB., Conclusions: Cytoprotection by low Na+ was not mediated by prevention of Na+-dependent tissue swelling. Rather, promotion of intracellular acidification likely mediates cytoprotection in low-Na+ buffer.

Hypothermia induces injury in its own right, but the mechanisms involved in the cell damage are still unclear. The aim of this study was to test the effects that glutathione (GSH) depletion induces on cell death in isolated rat hepatocytes, kept at 4 degrees C for 20 h, by modulating intracellular GSH concentration with diethylmaleate and buthionine sulfoximine (DEM and BSO). Untreated hepatocytes showed Annexin V stained cells (AnxV(+)), scarce propidium iodide stained cells (PI(+)) and presented a low level of lactate dehydrogenase (LDH) leakage after 20 h at 4 degrees C and rewarming at 37 degrees C. When DEM and BSO were added before cold storage, we observed a few AnXV(+) cells and an increase in PI(+) cells associated with LDH release in the incubation medium. Conversely, the addition of DEM and BSO only during rewarming caused a marked increase in cell death by apoptosis. Production of reactive oxygen species (ROS) and thiobarbituric acid species (TBARS), associated with a decrease in GSH concentrations, was higher when DEM and BSO were added before cold storage. Cells treated with DEM and BSO before cold storage showed lower ATP energy stores than hepatocytes treated with DEM and BSO only during rewarming. Pretreatment of hepatocytes with deferoxamine protected against apoptotic and necrotic morphology in conditions of GSH depletion. These results suggest that pretreatment of hepatocytes with DEM and BSO before cold storage induces necrosis, while the treatment of hepatocytes only during rewarming increases apoptosis. In both conditions, iron represents a crucial mediator of cell death.

Although the use of melatonin in the transplantation field has been suggested, it has not been previously tested in a liver cold-storage model. We used a rat liver model to study (a) the dose-dependent effect of melatonin on bile production, and (b) the potential of melatonin to improve liver function after cold-storage. Male Wistar rats were perfused with Krebs-Henseleit bicarbonate buffer (KHB) at 37 degrees C without or with 25, 50, 100 and 200 microM melatonin. Each dose of melatonin stimulated bile production. For cold-storage studies, livers were flushed with either University of Wisconsin (UW) or Celsior solution and stored for 20 hr at 4 degrees C. Reperfusion (120 min) was performed with KHB at 37 degrees C. In subsequent studies, 100 microM melatonin were added to the perfusate during the reperfusion period. ATP and melatonin levels in the tissue were measured. Bile analysis was performed by measuring melatonin, bilirubin and gamma-glutamyl transpeptidase (gamma-GT) levels in the fluid. A dose-dependent increase in bile secretion, associated with an enhanced melatonin and bilirubin levels in the bile were observed. Also, tissue levels of melatonin increased in a dose-dependent manner. When melatonin was added during the reperfusion period, bile production and bile bilirubin levels increased both with UW and Celsior solutions. The analysis of gamma-GT in the bile showed an increase in the Celsior-preserved liver and the addition of melatonin to the perfusate reduced this effect. Tissue ATP levels were higher when melatonin was added to the perfusion medium. Higher levels of melatonin in bile than in tissue were found. In conclusion, we demonstrate that melatonin improves significantly the restoration of liver function after cold-storage and reperfusion.

Several studies have demonstrated that matrix metalloproteinases (MMPs) are frequently implicated in the destruction of articular cartilage in arthritis. The control of MMP activity is dependent on the local concentration of tissue inhibitors of metalloproteinases (TIMPs), and the imbalance of the enzyme-to-inhibitor ratios plays an important role in the remodeling of articular tissues. Some cytokines such as interleukin (IL)-1 and tumor necrosis factor (TNF)-alpha which regulate leukocyte activities, promote MMP secretion and, as a consequence, cartilage degradation. The aim of the present study was to investigate whether a natural treatment is effective in reducing cartilage inflammation and degradation by influencing MMP and TIMP serum levels. Eighty patients with osteoarthritis (OA) were enrolled in the trial and were divided into group A (30 patients who did not undergo mud bath therapy), group B (28 patients repeating mud bath therapy more than 5 times and less than 10) and group C (22 patients repeating mud bath therapy more than 10 times). Blood samples were obtained from all the patients for assay of MMP-1, -2, -3, -8 and -9 and TIMP-1 and -2. The parameters were determined by an ELISA technique. Statistical indexes were calculated for each parameter and mean values were compared. The differences between mean values of MMP-3, -8 and -9 were statistically significant between group A and the treated groups (B and C). Analysis of variance established a significant difference (p < 0.05) between groups A and C in mean serum levels of MMP-8, MMP-9 showed a statistically significant difference (p < 0.05) in mean serum concentration between groups A and B. Regression analysis showed a very high R2 between MMP-2 and TIMP-2. One of the most interesting findings in this study was that MMP-3 serum levels were significantly lower in the treated groups, since this enzyme plays an important role in cartilage degradation, suggesting that mud bath therapy contributes to matrix integrity in OA cartilage. In contrast, MMP-8 and -9 were higher in the treated subjects and no correlation with TIMPs was evident. One possible explanation is that these enzymes are required for the efficient degradation and removal of already compromised cartilage matrix and that they operate as part of a matrix turnover and repair process. In conclusion, our data suggest that mud bath therapy alone is not able to influence chondrocyte metabolic activity in the advanced phases of OA. There could be a synergic and sequential association with pharmacologic therapy and/or interventions.

We evaluated the effects of nicergoline on antioxidant defense enzymes (detoxifying enzymes), during chronic treatment with haloperidol in rats. Chronic use of haloperidol (10 weeks, 1.5 mg/kg/day) induces a significant decrease in glutathione reductase, glutathione peroxidase and superoxide dismutase activity, in selected areas of the brain. Co-administration of nicergoline (20 days, 10 mg/kg/day) significantly restored the activity of these enzymes to levels comparable to those observed in control rats. These observations suggest beneficial effects of nicergoline in the prevention and in the treatment of haloperidol-induced side effects.

Background: The connection between osteoarthritis (OA) and osteoporosis (OP) has attracted considerable attention but reports about bone mass density (BMD) in OA are often contradictory. Some data indicate that BMD is higher in OA patients than in healthy subjects, whereas other studies showed no differences. It has been observed that mud pack treatment (MPT) induces a decrease in cytokines with bone-resorbing effects. The aim of this study is to evaluate the response of bone and connective tissue to physical exercise and thermal treatment., Methods: Forty osteoarthrosic patients were divided in group A (physical exercise and MPT), and group B (physical exercise alone). Blood and urine samples were collected before and after the treatments to assay blood metabolic markers and urinary hydroxyproline., Results: In group A, some parameters show statistically significant differences before and after mud pack treatment (MPT). In group B, all parameters present no statistical significant changes before and after the physical exercise program., Conclusions: Few studies established the importance of exercise to maintain normal cartilage and bone metabolism. In group A of the present study, an influence on all the parameters of bone metabolism is evident. It is possible that physical exercise only if combined with MPT stimulates physiologic bone metabolism and favors skeletal health., (Copyright 2002 Elsevier Science B.V.)

We evaluated the effects of 10-alpha-methoxy-9,10-dihydrolysergol (MDL) and 1-methyl-10-alpha-methoxy-9,10-dihydrolysergol (MMDL), two nicergoline metabolites, during chronic treatment with haloperidol in rats. Haloperidol induced a significant decrease in the glutathione (GSH) content in selected areas of the brain and in the liver. Prolonged administration of MDL, MMDL or nicergoline antagonized the haloperidol-induced GSH decrease. Lipid peroxidation in the cortex and striatum was suppressed by MDL, MMDL or nicergoline administration. Our results show that MDL, MMDL and nicergoline have antioxidant activity, preventing not only GSH depletion but also lipid peroxidation. These observations suggest beneficial properties of MDL and MMDL in the treatment of neuroleptic-induced side effects., (Copyright 2002 Elsevier Science B.V.)

Liver hypoxia still represents an important cause of liver injury during shock and liver transplantation. We have investigated the protective effects of beta-alanine against hypoxic injury using isolated perfused rat livers and isolated rat hepatocyte suspensions. Perfusion with hypoxic Krebs-Henseleit buffer increased liver weight and caused a progressive release of lactate dehydrogenase (LDH) in the effluent perfusate. The addition of 5 mmol/l beta-alanine to the perfusion buffer completely prevented both weight increase and LDH leakage. These findings were confirmed by histological examinations showing that beta-alanine blocked the staining by trypan blue of either liver parenchymal and sinusoidal cells. Studies performed in isolated hepatocytes revealed that beta-alanine exerted its protective effects by interfering with Na+ accumulation induced by hypoxia. The addition of gamma-amino-butyric acid, which interfered with beta-alanine uptake by the hepatocytes or of Na+/H+ ionophore monensin, reverted beta-alanine protection in either hepatocyte suspensions or isolated perfused livers. We also observed that liver receiving beta-alanine were also protected against LDH leakage and weight increase caused by the perfusion with an hyposmotic (205 mosm) hypoxic buffer obtained by decreasing NaCl content from 118 to 60 mmol/l. This latter effect was not reverted by blocking K+ efflux from hepatocyte with BaCl(2) (1mmol/l). Altogether these results indicated that beta-alanine protected against hypoxic liver injury by preventing Na+ overload and by increasing liver resistance to osmotic stress consequent to the impairment of ion homeostasis during hypoxia.

Several authors have demonstrated the pivotal role of proinflammatory cytokines in inducing progressive cartilage degradation and secondary inflammation of the synovial membrane in osteoarthritis (OA). It has recently been established that tumor necrosis factor (TNF)-alpha plays a well-defined role in the pathophysiology of inflammatory joint diseases and that binding to circulating soluble TNF-alpha receptors can inactivate it. We investigated the influence of mud pack treatment, which is able to diminish TNF-alpha serum values, on specific TNF receptor (sTNF-R) levels. Thirty-six patients with OA were enrolled and randomized into two groups. Group A underwent mud pack treatment and group B underwent thermal bath treatment. A group of 20 healthy untreated subjects was used as a control. Blood samples were collected at baseline and after treatment, and assays of sTNF-R55 and sTNF-R75 were performed in both groups. We found small changes in sTNF-Rs serum values but these were not statistically significant. sTNF-R55 serum values decreased by 0.4% after the therapy in group A, while in group B the decrease was -17.7%. sTNF-R75 was reduced by -21.17% in group A and by -10.6% in group B. In conclusion, through its thermic and ant/inflammatory activity mud pack treatment shows complex interaction with the most common factors of inflammatory and cartilage degradation. Our results suggest that the thermic component of this natural treatment is mainly involved in modulating inflammatory reaction and cartilage damage through binding of the circulating TNF, which controls the activation of the cells responsible for the production of proinflammatory cytokines.

The antioxidant properties of green and roasted coffee, in relation to species (Coffea arabica and Coffea robusta) and degree of roasting (light, medium, dark), were investigated. These properties were evaluated by determining the reducing substances (RS) of coffee and its antioxidant activity (AA) in vitro (model system beta-carotene-linoleic acid) and ex vivo as protective activity (PA) against rat liver cell microsome lipid peroxidation measured as TBA-reacting substances. RS of C. robustasamples were found to be significantly higher when compared to those of C. arabica samples (p < 0.001). AA for green coffee samples were slightly higher than for the corresponding roasted samples while PA was significantly lower in green coffee compared to that of all roasted samples (p < 0.001). Extraction with three different organic solvents (ethyl acetate, ethyl ether, and dichloromethane) showed that the most protective compounds are extracted from acidified dark roasted coffee solutions with ethyl acetate. The analysis of acidic extract by gel filtration chromatography (GFC) gave five fractions. Higher molecular mass fractions were found to possess antioxidant activity while the lower molecular mass fractions showed protective activity. The small amounts of these acidic, low molecular mass protective fractions isolated indicate that they contain very strong protective agents.

Nitric oxide (NO) has recently been proposed as an important mediator in inflammatory phases and in loss of cartilage. In inflammatory arthritis NO levels are correlated with disease activity and articular cartilage is able to produce large amounts of NO with the appropriate inducing factors such as cytokines and/or endotoxin. Neutrophils also play an important role in inflammatory reactions and the level of myeloperoxidase, a constituent of neutrophil granules, is related to the intensity of the inflammation. Because there is evidence that suggests that mud packs influence the main cytokines involved in cartilage damage, we tried to determine whether NO and myeloperoxidase are involved in the mechanisms of action of mud bath treatment. We enrolled 37 subjects and randomly assigned them to two groups: 19 patients underwent mud bath treatment (group A) while 18 patients underwent bath treatment alone. Blood samples were obtained before and after the treatment cycles to assay serum levels of NO, myeloperoxidase (MPO) and glutathione (GSH)-peroxidase. The results showed a statistically significant decrease in NO and myeloperoxidase serum values in groups A and B, while GSH-peroxidase was not significantly increase in either of the groups; no correlation was found between NO, myeloperoxidase and GSH-peroxidase serum values. Mud bath treatment can exert beneficial effects on cartilage homeostasis and inflammatory reactions, influencing NO and decreasing myeloperoxidase serum values. The increase in GSH-peroxidase was not correlated with the reduction of other biochemical markers, suggesting that mud bath treatment has different mechanisms of action.

The aim of this study was to evaluate the possible effects of nicergoline, a semisynthetic ergot derivative, on the biochemical changes observed during chronic treatment with haloperidol in male Sprague-Dawley rats. Chronic treatment with haloperidol induced a significant decrease in the cellular glutathione (GSH) content in selected areas of the brain (cerebellum, striatum and cortex) and in the liver. Prolonged nicergoline administration was able to antagonize the haloperidol-induced GSH decrease, maintaining the GSH concentration at levels comparable to those observed in the control group. Analysis of the energy charge revealed changes similar to those observed for GSH: haloperidol induced a significant decrease in ATP and energy charge that was completely reversed by repeated nicergoline administration. In conclusion, chronic treatment with the classical antipsychotic haloperidol induces profound biochemical changes in the brain and in the liver. Nicergoline treatment is able to counteract the haloperidol-induced decrease in GSH levels and energy charge, suggesting a potential role of the drug in the treatment of neuroleptic-induced side effects.

This paper reports the toxicological evaluation of pidotimod ((R)-3-[(S)-(5-oxo-2-pyrrolidinyl) carbonyl]-thiazolidine-4-carboxylic acid, PGT/1A, CAS 121808-62-6). Its acute toxicity in mice, rats and dogs was very low after oral, i.v., i.m. and i.p. administration. The repeated administration studies in rats were performed for 4 months via the i.p. route and for 12 months via the oral route. Pidotimod did not show toxic effects at dosages up to 200 mg/kg i.p. and 800 mg/kg p.o. These dosages correspond to 32.5 times the maximum dosage intended for clinical use. The repeated administration studies in dogs were performed for 26 weeks via the i.m. route and for 52 weeks via the oral route. Pidotimod did not show toxic effects at dosages up to 300 mg/kg i.m. and 600 mg/kg p.o.. It did not affect male or female rat fertility at dosages up to 600 mg/kg by oral and 500 mg/kg by i.v. route. The compound was not teratogenic in rats (600 mg/kg p.o. and 1000 mg/kg i.v.), with no effects on subsequent embryofoetal development at dosages up to 1000 mg/kg/day, and in rabbits (300 mg/kg p.o. and 500 mg/kg. i.v.). There were no peri- and postnatal toxic effects in rats (600 mg/kg p.o. and 500 mg/kg i.v.). Local tolerability of pidotimod after i.m. administration was very good. In conclusion pidotimod is characterized by a high safety margin in all animal species.

The objective of this in vitro study was to examine the response of mixed cultures of Sertoli and germ cells to treatment with thallium (Tl) at the range of concentrations that, in previous studies, was shown in vivo to affect reproduction. Cultures were prepared from the testis of Sprague-Dawley rats. Cultures containing approximately 3.75 x 10(6) cells/ml were treated with Tl concentrations corresponding to 35, 7, and 1.4 micrograms Tl/g testis, estimated from protein content of cultures. Observations at 24, 48, and 72 h after treatment showed a significant release of germ cells into the culture medium that was both concentration and time dependent. Cultures treated with 35 micrograms Tl/g testis showed a threefold increase in germ-cell detachment compared with controls after only 24 h of exposure. As the treatment time increased to 48 h of exposure, even cultures exposed at the lowest Tl concentration (1.4 micrograms Tl/g testis) showed significant loss of germ cells. After 48 h, cultures exposed to 7 micrograms Tl/g testis exhibited a 2.5-fold increase in germ-cell detachment, and those exposed to 35 micrograms Tl/g testis exhibited a 10-fold increase over controls. Morphological investigations of cell cultures showed evident loss of germ cells with significant reduction in prepachytene and pachytene spermatocytes and changes in the shape of Sertoli cells. These results are in agreement with in vivo studies, in which thallium treatment at comparable exposure levels manifested its earliest toxic testicular effects in Sertoli and germ cells. They also demonstrate the usefulness of this in vitro culture technique to assess toxic testicular damage rapidly.