Polysaccharide-based layer-by-layer nanoarchitectonics with sulfated chitosan for tuning anti-thrombogenic properties.

The development of blood-interacting surfaces is critical to fabricate biomaterials for medical use, such as prostheses, implants, biosensors, and membranes. For instance, thrombosis is one of the leading clinical problems when polymer-based materials interact with blood. To overcome this limitation is necessary to develop strategies that limit platelets adhesion and activation. In this work, hyaluronan (HA)/chitosan (Chi) based-films, recently reported in the literature as platforms for tumor cell capture, were developed and, subsequently, functionalized with sulfated chitosan (ChiS) using a layer-by-layer technique. ChiS, when compared to native Chi, presents the unique abilities to confer anti-thrombogenic properties, to reduce protein adsorption, and also to limit calcification. Film physicochemical characterization was carried out using FTIR and XPS for chemical composition assessment, AFM for the surface morphology, and contact angle for hydrophilicity evaluation. The deposition of ChiS monolayer promoted a decrease in both roughness and hydrophilicity of the HA/Chi films. In addition, the appearance of sulfur in the chemical composition of ChiS-functionalized films confirmed the film modification. Biological assay indicated that the incorporation of sulfated groups limited platelet adhesion, mainly because a significant reduction of platelets adhesion to ChiS-functionalized films was observed compared to HA/Chi films. On balance, this work provides a new insight for the development of novel antithrombogenic biomaterials, opening up new possibilities for devising blood-interaction surfaces.

In vitro evaluation of anti-fungal activity of tropicamide against strains of Candida spp. resistant to fluconazole in planktonic and biofilm form.

Candida spp. is considered to be the third or fourth most common cause of bloodstream infections associated with healthcare services in the world. Currently, several strains exhibit resistance to the traditional treatments, making the development of new therapeutic molecules necessary. Drug repositioning is an alternative that can be used to work around problems such as toxicity, cost and time in the development of new drugs. This study aims to evaluate the in vitro antifungal effect of tropicamide, molecule of anticholinergic action, against planktonic cells of Candida spp. and biofilm of C. albicans. Six strains of different Candida species were used to determine the minimum inhibitory concentration (MIC) of tropicamide and fluconazole according to CLSI document M27-A3 and one strain of C. albicans was used to evaluate the activity of tropicamide against biofilms. In concentrations of 64µg/mL, the tropicamide exhibited 50% of inhibitory activity in planktonic cell and in concentrations of 128µg/mL is able to inhibit the formation of C. albicans biofilm. Despite the inhibitory activity shown at the present study, the use of a larger number of strains, as well as in vivo cytotoxicity assays, is necessary to confirm the hypothesis that tropicamide can be used as an adjuvant agent in the treatment of infections by the Candida genus.

Copper Ion Uptake by Chitosan in the Presence of Amyloid-ß and Histidine.

Alzheimer's disease (AD) is related to the anomalous binding that occurs between amyloid-ß peptide (Aß) and copper ion, through imidazole ring of histidine (His), as stated in the literature. It is also known that high-affinity metal ion chelators can be pharmacologically used as a possible therapeutic approach. In this work, we tested the ability "in vitro" of chitosan (Chi) to reduce Aß aggregation and Thioflavin T binding assay indicated that chitosan has affinity for Aß and interferes in its aggregation. We also tested the ability of Chi to uptake copper ions in the presence of Aß or His. Equilibrium data reveals that chitosan acted as an effective chelating agent competing with Aß and histidine for copper binding. The addition of histidine or Aß in the system promotes an unfolding of chitosan chains, as verified by small-angle X-ray scattering. Extended X-ray absorption fine structure and XPS spectra show that new copper interactions with groups containing nitrogen in the presence of histidine may occur. These results can help understanding fundamental chemical interactions among species detected in AD and biopolymers, opening up possibilities for new treatment approaches for this disease.

One-year follow-up of the immune profile in serum and selected sites of generalized and localized aggressive periodontitis.

BACKGROUND: The local and systemic immunological profiles of important inflammatory mediators in the localized (LAgP) and generalized (GAgP) forms of aggressive periodontitis are still unknown, as well as the effect of periodontal therapy on these parameters. The aim of this prospective study was to evaluate clinical and immune responses of patients with AgP undergoing nonsurgical treatment. MATERIAL AND METHODS: Eighteen patients with GAgP, 10 with LAgP and 10 healthy participants were included in this study. AgP participants were submitted to scaling and root planing plus systemic antibiotics (amoxicillin and metronidazole). At baseline and 1-year follow-up were measured clinical parameters, such as probing depth [PD] and clinical attachment loss [CAL], and the levels of 10 immunological mediators (GM-CSF, M-CSF, MCP-1, ICAM-1, CXCL8, IL-1ß, TNF-α, IL-17, IL-4, and IL-10) in the gingival crevicular fluid (GCF) of selected sites [AgP forms: PD ≥ 6 mm or the deepest, bleeding on probing (BoP) and bone loss measured by periapical radiography; healthy individuals: PD ≤ 3 mm, no BoP, no bone loss] and serum. RESULTS: After periodontal treatment both forms of AgP presented a significant reduction of PD and CAL, an increase of GM-CSF, ICAM-1, MCP-1, TNF-α, IL-17, IL-4, and IL-10 in the GCF, as well as of GM-CSF and IL-4 in the serum, and a reduction in the serum concentration of IL-1ß. Serum levels of M-CSF, ICAM-1, and MCP-1 remained significantly below those found in healthy individuals in both forms of AgP even after therapy. An increase in the systemic or local levels of MCP-1, ICAM-1 and the anti-inflammatory profile (IL-4, IL-10) was correlated with an improvement in clinical parameters of LAgP patients. Also, a local reduction of IL-1ß levels in both forms of AgP was correlated with an increase in the clinical attachment gain. CONCLUSION: Nonsurgical periodontal therapy was successful in improving clinical parameters and modulating the immune response in both forms of AgP. However, this therapeutic approach does not seem to affect the deficient level of important serum mediators involved in mechanisms of cell transmigration.

Long-term outcomes from implants installed by using split-crest technique in posterior maxillae: 10 years of follow-up.

OBJECTIVE: The aim of the present 10-year retrospective study was to evaluate the success and survival rates of narrow diameter implants (NDIs) placed in combination with a split-crest technique. MATERIALS AND METHODS: Twenty-one healthy individuals who received prosthetic rehabilitation supported by narrow diameter implants (NDIs) installed in atrophic maxillary posterior areas immediately after split-crest procedure were included in the study. Six to eight weeks after implant placement, the prosthetic rehabilitations were delivered. Periapical radiographs were taken at the 6-month and 10-year time interval after implant loading to assess bone marginal level around the implants. In addition, survival and success indexes were also obtained at these time intervals. RESULTS: Forty NDIs were placed in 21 patients. At the end of the 10-year follow-up period, seven patients had dropped out, two implants were lost, and nine prostheses presented some type of deficiency (ceramic fracture or retaining screw fracture). At the 10-year time interval, the implant survival rate was 97% and the success rate was 95%. The marginal bone loss at the 6-month and 10-year time intervals was, respectively, 0.47 (SD 0.91) mm and 1.93 (SD 0.93) mm. CONCLUSION: Narrow diameter implants installed immediately after split-crest procedure may successfully support prosthetic rehabilitations after long-time intervals.

High prevalence of micropenis in 2710 male newborns from an intensive-use pesticide area of Northeastern Brazil.

Exposure to endocrine-disrupting chemicals (EDCs) has been suggested to contribute to the increasing trends of external genital malformation in male newborns. In Northeastern Brazil, the poor sanitary conditions found in the favelas encourage the widespread use of pesticides. This 2-year study of a total birth cohort of full-term male newborns in the regional hospitals of Campina Grande (Paraíba, Brazil) sought to (1) accurately establish for the first time the incidences of neonatal male genital malformations, (2) investigate the endocrine and genetic aetiologies of these malformations, and (3) evaluate their associations with possible prenatal exposure to EDCs. A total of 2710 male newborns were explored for cryptorchidism, hypospadias and micropenis. Cases were referred to the Pediatric Endocrine Clinic for endocrine and genetic investigations, and all parents were interviewed about their environmental/occupational exposure to EDCs before/during pregnancy by paediatric endocrinologists using a detailed questionnaire. We observed 56 cases of genital malformation (2.07%), including 23 cryptorchidism (0.85%), 15 hypospadias (0.55%), and 18 micropenis (0.66%). All cases exhibited normal/subnormal testosterone production and none presented androgen receptor or 5α-reductase gene mutation. More than 92% of these newborns presented foetal contamination by EDCs, as their mothers reported daily domestic use of pesticides (i.e., DDT) and other EDCs. Most of these undervirilized male newborns presented additional EDC contamination, as 80.36% of the mothers and 58.63% of the fathers reported paid or unpaid work that entailed the use of pesticides and other EDCs before/during pregnancy for the mothers and around the time of fertilization for the fathers. The high rate of micropenis in our population associated with an elevated percentage of parental environmental/occupational exposure to EDCs before/during pregnancy indicates that foetal contamination may be a risk factor for the development of male external genital malformation.

Gene expression in swine granulosa cells and ovarian tissue during the estrous cycle.

The components of the insulin-like growth factor (IGF) system appear to be involved in regulation of ovarian follicular growth and atresia in the pig. We investigated the expression pattern of mRNAs for IGF1 (IGF1), its binding proteins (IGFBP1, IGFBP2, IGFBP3, and IGFBP5), and epidermal growth factor in swine follicle cells and ovarian tissue throughout the estrous cycle using the real-time quantitative PCR technique. The results of gene expression were analyzed using linear regression with gene expression as a dependent variable and days of estrous cycle as an independent variable. Additionally, an analysis was made of the correlation of expression levels with plasma concentration of follicle-stimulating hormone, luteinizing hormone, estradiol-17ß, progesterone, and prolactin. Expression of mRNA of all of these genes was detected in granulosa cells and ovarian tissue. IGFBP3 mRNA showed a quadratic expression pattern (P ≤ 0.001) and was significantly and positively correlated with progesterone (r = 0.81; P ≤ 0.01) but negatively correlated with prolactin (r = -0.596; P ≤ 0.05). Expression of the other genes was unaffected by the stage of the estrous cycle. Real-time quantitative PCR effectively detected all transcripts, including the very low levels of IGFBP1 transcripts, and could be used for studies of follicle dynamics.

Assessment of linear measurements of bone for implant sites in the presence of metallic artefacts using cone beam computed tomography and multislice computed tomography.

The objective was to evaluate the influence of dental metallic artefacts on implant sites using multislice and cone-beam computed tomography techniques. Ten dried human mandibles were scanned twice by each technique, with and without dental metallic artefacts. Metallic restorations were placed at the top of the alveolar ridge adjacent to the mental foramen region for the second scanning. Linear measurements (thickness and height) for each cross-section were performed by a single examiner using computer software. All mandibles were analysed at both the right and the left mental foramen regions. For the multislice technique, dental metallic artefact produced an increase of 5% in bone thickness and a reduction of 6% in bone height; no significant differences (p>0.05) were detected when comparing measurements performed with and without metallic artefacts. With respect to the cone-beam technique, dental metallic artefact produced an increase of 6% in bone thickness and a reduction of 0.68% in bone height. No significant differences (p>0.05) were observed when comparing measurements performed with and without metallic artefacts. The presence of dental metallic artefacts did not alter the linear measurements obtained with both techniques, although its presence made the location of the alveolar bone crest more difficult.

Rabbit model of uncontrolled hemorrhagic shock and hypotensive resuscitation

Clinically relevant animal models capable of simulating traumatic hemorrhagic shock are needed. We developed a hemorrhagic shock model with male New Zealand rabbits (2200-2800 g, 60-70 days old) that simulates the pre-hospital and acute care of a penetrating trauma victim in an urban scenario using current resuscitation strategies. A laparotomy was performed to reproduce tissue trauma and an aortic injury was created using a standardized single puncture to the left side of the infrarenal aorta to induce hemorrhagic shock similar to a penetrating mechanism. A 15-min interval was used to simulate the arrival of pre-hospital care. Fluid resuscitation was then applied using two regimens: normotensive resuscitation to achieve baseline mean arterial blood pressure (MAP, 10 animals) and hypotensive resuscitation at 60 percent of baseline MAP (10 animals). Another 10 animals were sham operated. The total time of the experiment was 85 min, reproducing scene, transport and emergency room times. Intra-abdominal blood loss was significantly greater in animals that underwent normotensive resuscitation compared to hypotensive resuscitation (17.1 ± 2.0 vs 8.0 ± 1.5 mL/kg). Antithrombin levels decreased significantly in normotensive resuscitated animals compared to baseline (102 ± 2.0 vs 59 ± 4.1 percent), sham (95 ± 2.8 vs 59 ± 4.1 percent), and hypotensive resuscitated animals (98 ± 7.8 vs 59 ± 4.1 percent). Evidence of re-bleeding was also noted in the normotensive resuscitation group. A hypotensive resuscitation regimen resulted in decreased blood loss in a clinically relevant small animal model capable of reproducing hemorrhagic shock caused by a penetrating mechanism.

Rabbit model of uncontrolled hemorrhagic shock and hypotensive resuscitation.

Clinically relevant animal models capable of simulating traumatic hemorrhagic shock are needed. We developed a hemorrhagic shock model with male New Zealand rabbits (2200-2800 g, 60-70 days old) that simulates the pre-hospital and acute care of a penetrating trauma victim in an urban scenario using current resuscitation strategies. A laparotomy was performed to reproduce tissue trauma and an aortic injury was created using a standardized single puncture to the left side of the infrarenal aorta to induce hemorrhagic shock similar to a penetrating mechanism. A 15-min interval was used to simulate the arrival of pre-hospital care. Fluid resuscitation was then applied using two regimens: normotensive resuscitation to achieve baseline mean arterial blood pressure (MAP, 10 animals) and hypotensive resuscitation at 60% of baseline MAP (10 animals). Another 10 animals were sham operated. The total time of the experiment was 85 min, reproducing scene, transport and emergency room times. Intra-abdominal blood loss was significantly greater in animals that underwent normotensive resuscitation compared to hypotensive resuscitation (17.1 ± 2.0 vs 8.0 ± 1.5 mL/kg). Antithrombin levels decreased significantly in normotensive resuscitated animals compared to baseline (102 ± 2.0 vs 59 ± 4.1%), sham (95 ± 2.8 vs 59 ± 4.1%), and hypotensive resuscitated animals (98 ± 7.8 vs 59 ± 4.1%). Evidence of re-bleeding was also noted in the normotensive resuscitation group. A hypotensive resuscitation regimen resulted in decreased blood loss in a clinically relevant small animal model capable of reproducing hemorrhagic shock caused by a penetrating mechanism.

Anatomical evaluation of some morphological abnormalities related to periodontal diseases

The presence of some dental abnormalities as a predisposal factor to installation of localized periodontal alterations. The present study was to evaluate the frequency of development abnormalities present on a sample of molars that may predispose to occurrence and progression of periodontal disease. Two hundred and seventy seven molars (141 maxillary and 136 mandibular molars) were selected for this study. The evaluations were performed by two examiners together who was trained and calibrated for the study. All measurements were made by direct visualization with a magnifying glass. The following clinical parameters were measured: Enamel cervical projections; Root trunk: in the three different extensions (<3 mm, >3 mm and <6 mm, >6 mm); Enamel pearls: presence (1) or absence (0). The anatomic observations were made on four surfaces of the tooth: mesial, distal, vestibular and palatal/lingual. Descriptive statistics and percentage distribution were performed. A total of 130 molars showed at least some degree of enamel cervical projection and the most frequent score was the degree 1, according to Masters and Hoskins classification. Fifteen teeth presented enamel pearls and the root trunk was more evident on the group with variation from 3 to 6 mm of extension, observed in 64 teeth. It can be concluded that the presence of development abnormalities is a frequent finding in molars and it has to be taken into consideration during periodontal examination and therapy.

Leucemia linfoide aguda a importancia do laboratorio de liquor para o sucesso do tratamento / Acute lymphoblastic leukemia: the importance of cerebrospinal fluid laboratory for successful treatament

A Leucemia Linfoide Aguda (LLA) e uma doenca caracterizada pelo acumulo de linfoblastos em numerosos orgaos e tecidos, notadamente na medula ossea. Entretanto as celulas malignas da LLA tem uma predisposicao de infiltrar o Sistema Nervoso Central (SNC) e os testiculos, sendo estes, considerados ¡°santuarios¡±. A importancia ao diagnostico da avaliacao citologica do liquido cefalorraqueano(Liquor) tornou-se fundamental para adequacao do tratamento, prognostico e para o monitoramento de eventuais recaidas. Citologicamente pode-se determinar um ¡°STATUS¡±, sendo que a avaliacao mais aceita atualmente ao diagnostico deve seguir os seguintes criterios: Status 1: puncao nao traumatica com ausencia de blastos apos citocentrifugacao. Status 2: puncao nao traumatica com presenca de blastos apos citocentrifugacao e leucocitos ¡Ü5/mm3. Status 3: puncao nao traumatica com presenca de blastosapos citocentrifugacao e leucocitos ¡Ý5/mm3 . A puncao traumatica deve ser classificada como risco, pois pode haver a infiltracao na hora da puncao. O objetivo deste trabalho e definir criteriosamente a importancia da atuacao do Farmaceutico Bioquimico no Laboratorio de Liquor auxiliando o clinico na avaliacao de conduta terapeutica baseado na avaliacao citologica do liquido cefalorraqueano.

Acute Lymphoblastic Leukemia (ALL) is an illness characterized for the accumulation of blasts in numerous organ and tissue, essential in the blone marrow. However the malignant cells of the ALL have a predisposition to infiltrate central nervous system(CNS) and the testicules, being been these, considered "sanctuaries". The importance to the diagnosis of the cytological evaluation of the cerebrospinal fluid (CSF), became basic for adequacy of the treatment, prognostic and for the involvement of eventual fallen again. Cytologically a "STATUS" can be determined, being most accepted currently to the diagnosis must follow the following criteria:CNS1 (puncture nontraumatic without leukemic blasts after ytocentrifugation), CNS2 (puncture nontraumatic, ¡Ü5 WBC/mm3 CSF with identifiable blasts after cytocentrifugation), CNS3 (puncture nontraumatic, ¡Ý5 WBC/mm3 CSF with identifiable blasts aftercytocentrifugation). TLP(+) ¨C puncture traumatic with blasts, and TLP(-) ¨C puncture traumatic without blasts. The traumatic puncture must be classified as risk therefore it can have infiltration in the hour puncture. The objective of this work is reintensification to define the importance of the performance of the Pharmaceutical Biochemist in the Cerebrospinal Fluid Laboratory assisting the physician in the based evaluation of therapeutical behavior in the cytological evaluation of the Cerebrospinal Fluid.

Diabetes modulates gene expression in the gingival tissues of patients with chronic periodontitis.

AIM: This study evaluated whether diabetes modulates gene expression [interleukin (IL)-1beta, IL-1ra, IL-6, IL-8, IL-10; tumor necrosis factor (TNF)-alpha; interferon (IFN)-gamma, receptor activator of NF-kappaB ligand (RANKL) and osteoprotegerin (OPG)] in sites with periodontitis. MATERIALS AND METHODS: Gingival biopsies were harvested and divided into three groups--Control group: systemically and periodontally healthy subjects (n = 10); Periodontitis group: systemically healthy subjects diagnosed with chronic periodontitis (n = 20); Diabetes group: type 1 diabetic subjects, diagnosed with chronic periodontitis (n = 20). Total RNA was obtained and analyzed by quantitative polymerase chain reaction. RESULTS: Data analysis demonstrated that, except for OPG, mRNA levels for all factors were increased by inflammation (P < 0.001). Interleukin-1beta, IL-1ra, IL-6, IL-8, IFN-gamma, and RANKL mRNA levels were higher in the diabetic group when compared with the control non-periodontitis group (P < 0.05), whereas IL-10 and OPG were lower (P < 0.05). No difference was observed for TNF-alpha between diabetic and control groups (P > 0.05). Diabetes lowered IL-1beta, IL-8, IL-10, TNF-alpha, RANKL, and OPG mRNA levels in sites with comparable type of periodontitis (P < 0.001). Moreover, increased RANKL:OPG and IL-6:IL-10 ratios were found. CONCLUSION AND CLINICAL RELEVANCE: Taken together, these data suggest that decreased levels of IL-10 and OPG may play an important role in the periodontal breakdown in diabetic patients.

Smoking modulates interleukin-6:interleukin-10 and RANKL:osteoprotegerin ratios in the periodontal tissues.

BACKGROUND AND OBJECTIVE: This study evaluated the effect of smoking on the gene expression of interleukin-1alpha, -1ra, -6, -8 and -10, tumor necrosis factor-alpha, matrix metalloproteinase (MMP)-2 and -8, receptor activator of NF-kappaB ligand (RANKL) and osteoprotegerin, in sites with periodontitis. MATERIAL AND METHODS: Gingival biopsies were divided into three groups: the healthy group (periodontally healthy subjects; n=10); the periodontitis group [subjects with severe chronic periodontitis who never smoked (probing depth>or=7 mm) (n=25)]; and the smoking group (subjects diagnosed with severe chronic periodontitis who smoked>or=1 pack per day for at least 10 years; n=25). Gene and protein expressions were analyzed by quantitative polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. RESULTS: Data analysis demonstrated that, except for MMP-8 and osteoprotegerin, the levels of all factors were increased by inflammation (p<0.001). The levels of interleukin-1alpha, -1ra, -6 and -8, and RANKL, were higher in smokers with periodontitis compared with controls, whereas the levels of interleukin-10, MMP-8 and osteoprotegerin were lower (p<0.001). Smoking lowered the levels of interleukin-1alpha, -8, -10, tumor necrosis factor-alpha, MMP-8 and osteoprotegerin, and increased the levels of interleukin-6 and -1ra in sites with a comparable type of periodontitis (p<0.001). CONCLUSION: In conclusion, smoking modulates gene expression in the periodontium, and the influence of smoking on periodontal disease may involve effects of interleukin-6:interleukin-10 and RANKL:osteoprotegerin ratios.

Periodontal healing may be affected by aging: a histologic study in rats.

BACKGROUND AND OBJECTIVE: Although wound healing has been reported to be impaired with aging, very little is known about its effect on periodontal tissues. Therefore, the aim of this study was to evaluate, histologically in rats, the influence of aging on a spontaneous periodontal healing model. MATERIAL AND METHODS: Twenty-four male Wistar rats were used and assigned to the following groups: control (n = 12; 2 mo old) and aged (n = 12; 18 mo old). Fenestration defects (4 x 3 x 1 mm) were created bilaterally at the buccal aspect of the distal root of the first mandibular molars, and the mandibulae were retrieved 3 and 6 wk postoperatively. The percentage of bone fill and density of newly formed bone, new cementum formation (NC), and the extension of the remaining defect (ERD) were histometrically obtained. RESULTS: Intragroup analysis demonstrated that, except for cementum, all histological parameters significantly improved over time (p < 0.05). Intergroup analysis additionally showed that the defects were initially similar in size, and that at 3 wk aging negatively influenced newly formed bone (86.38 +/- 2.99% and 73.06 +/- 3.21%, p < 0.001, for groups control and aged, respectively), BF (75.84 +/- 16.53% and 57.70 +/- 22.28%, p = 0.014) and ERD (0.41 +/- 0.20 mm and 1.17 +/- 0.37 mm, p < 0.001). At 6 wk, aging negatively influenced newly formed bone (88.12 +/- 2.90% and 78.19 +/- 5.35%, p < 0.001, for groups control and aged, respectively) and ERD (0.01 +/- 0.006 mm and 0.34 +/- 0.18 mm, p = 0.003), but not BF (98.15 +/- 2.43% and 87.87 +/- 11.63%, p > 0.05). No new cementum was formed along the root surface in the above groups. CONCLUSION: Within the limits of the present study, data analysis suggests that aging may impair, but not prevent, periodontal healing.

Clinical and epidemiological characteristics of injuries caused by venomous snakes observed at the Hospital for Tropical Diseases of Araguaína, Tocantins State, Brazil, from 1995 to 2000

Injuries caused by venomous snakes are considered a problem of public health in Brazil, and further studies for a better knowledge are very important. The aim of this work is to describe clinical and epidemiological characteristics that were observed from 1995 to 2000 in the Hospital for Tropical Diseases of Araguaína, Tocantins State, Brazil, which is a unit of health that takes care of patients suffering from tropical diseases. We studied 440 individuals and the most common characteristics observed were masculine sex, age among 15-45 years, bite in low members, and injuries caused by snakes of the Bothrops genus. The signs and symptoms more frequently observed were edema, pain, erythema, and bleeding. The most observed systemic manifestation was alteration of blood coagulation. The most frequent complications were abscess, necrosis, bacterial infection, and renal failure. The mortality rate was 3%. These data are very important for the evaluation of the problem

Genotoxic effects of stannous chloride (SnCl2) in K562 cell line.

The toxic effects of SnCl2 in K562 cells were analyzed in this study. This cell line is resistant to reactive oxygen species (ROS) making it suitable to evaluate the impact of SnCl2 in culture either through ROS or by direct toxicity using Trypan blue dye exclusion, comet and flow cytometry assays. An important loss of viability induced by SnCl2 in a dose-response manner was observed in cells treated in Tris-buffered saline (TBS). This necrotic cell death was further confirmed by flow cytometry. On the other hand, there was no loss of viability when cells were treated in rich medium (RPMI). DNA damage was visualized in SnCl2-treated K562 cells in both tested conditions. The data indicate that SnCl2 induces DNA damage and reduces K562 viability. Both actions seem to be correlated with ROS formation and direct linkage to DNA.

Dna damage in peripheral blood nuclear cells assessed by comet assay from individuals submitted to scintigraphic examinations.

Stannous chloride (SnCl2) is employed as a reducing agent to obtain Technetium-99m-labelled radiophamaceuticals in nuclear medicine kits, being injected endovenously in humans. Toxic effects of these kits were not studied, thus making it important to evaluate their impact in humans. In this study, the toxic effects were evaluated from peripheral blood nuclear cells (PBNC) from patients who received radiopharmaceuticals obtained using such kits. The analyses included results performed by comet assay. DNA damage was visualized in PBNC samples collected within a time up to 2 hr, and 24 hr after radiopharmaceutical injection in the patients. Initially we observed an increase of comet signals, which subsequently were reduced to zero after 24 hr. The diminishing of comet amounts probably is associated with DNA repair of damaged cells or with the elimination by apoptosis of cells whose DNA are not repaired.

Deletion 5p11 accompanied by multiple numerical changes in testicular lymphoma.

We describe a case of testicular B cell lymphoma with deletion of chromosome 5, del(5)(p11), as a sole structural abnormality. Histopathological diagnosis of the tumor was a high-grade lymphoma of the diffuse type containing cells positive for B cell specific antigen (CD20) and negative for the leukocyte common antigen (CD45). Deletion 5p may define the region of a tumor suppressor gene that could be associated with tumor progression and invasiveness and may serve as an indicator of poor prognosis in testicular lymphomas.