Analysis of high risk factors for chromosomal aberrations in peripheral blood lymphocytes of 200 radiation workers in Hainan Province / 上海预防医学

ObjectiveTo investigate the current status and high-risk factors of chromosomal aberrations in peripheral blood lymphocytes （PBL） of radiation workers in Hainan Province. MethodsA total of 200 radiological workers who underwent occupational health examination in Hainan Provincial Hospital of Traditional Chinese Medicine from January 2021 to December 2021 were selected to collect the occupational health examination data and the rate of PBL chromosomal aberrations. The influencing factors of PBL chromosomal aberrations were analyzed by logistic regression model. The predictive value of logistic regression prediction model on PBL chromosomal aberrations were determined by using the reciver operator characteristic （ROC） curve. ResultsA total of 20 000 cells （100 cells/person） were tested. The chromosomal aberration rate was 0.37% （74/20 000） and the PBL chromosomal aberration rate in the subjects was 6.00% （12/200）. Univariate analysis showed that PBL chromosomal aberrations in radiological workers were related to age， length of service， type of work and education （all P<0.05）， but not to gender （P>0.05）. The logistic regression prediction model was constructed based on the influencing factors， with χ2=9.413， df=9， P=0.852， suggesting a good model fit. The logistic regression prediction model predicted the area under the curve （AUC） for the occurrence of PBL chromosomal aberrations in radiation workers was 0.914 （95%CI： 0.866‒0.949）， with a cut-off value of 3.05， corresponding to a prediction sensitivity and specificity of 100.00% and 75.98%， respectively. ConclusionThe incidence of PBL chromosomal aberrations in radiological workers in Hainan Province was 6.00%， with age， working age and job type as high-risk factors and education level as a protective factor. The prediction model constructed by the above factors can provide a reliable basis for clinical prediction of PBL chromosomal aberrations in radiological workers.

Evaluation on genotoxicities of raceanisodamine hydrochloride injection / 药学实践杂志

Objective To study the genotoxicities of raceanisodamine hydrochloride injection. Methods Bacterial reverse mutation test, in vitro Chromosomal aberration test and in vivo Micronucleus test were performed to investigate the genotoxicities of raceanisodamine hydrochloride injection. Results The Ames test showed that raceanisodamine hydrochloride injection did not increase mutagenicity for TA1535, TA102, TA100, TA98 and TA97 strains at the dosage of 0.5, 5, 50, 500, 5000 μg per plate under two parallel system conditions (±S9). Results of CA test indicated that there was no statistical difference between raceanisodamine hydrochloride injection groups (doses of 58.75,117.5 and 235.0 μg/ml) and the solvent control group under two parallel system conditions (±S9). In MNT test, with doses of 7.5, 15.0 and 30.0 mg/kg respectively, the micronucleus induction rate of bone marrow of ICR mice was not statistically significant (P>0.05) when compared with that of vehicle control group in all dose groups. Conclusion Under the conditions of these study, the results indicated that raceanisodamine hydrochloride injection had no mutagenicity to Salmonella typhimurium, had no aberration effect on the chromosome of mammalian cultured cells, and had no effect on inducing micronucleus of bone marrow polychromatic erythrocytes in ICR mouse. All test results showed that raceanisodamine hydrochloride injection had no potential carcinogenicities and genetic toxicities under the test conditions.

A Case of Wolf-Hirschhorn Syndrome with Early Rehabilitation Intervention from the Neonatal Period / The Japanese Journal of Rehabilitation Medicine

Wolf-Hirschhorn syndrome is a chromosomal aberration caused by a deletion of the distal short arm of chromosome 4, characterized by distinct craniofacial features, failure to thrive, psychomotor developmental retardation, epilepsy, and feeding disorders. We report a case of patient with Wolf-Hirschhorn syndrome who underwent interventional rehabilitation commencing from the neonatal period in the neonatal intensive care unit. The patient was born at gestational age of 38 weeks 0 days, weighing 1583 g, with an Apgar score of 4/9, and was diagnosed with partial monosomy of the short arm of chromosome 4. Postnatal inspiratory stridor exacerbation was noted for which high-flow nasal cannula therapy was initiated. Rehabilitation commenced on the 18th day after the infant's birth, to promote sensorimotor development. Initially, the trunk was in a low muscle tension and unstable state. Therefore, we first prescribed rest followed by sensorimotor rehabilitation. When the infant's clinical condition stabilized, we performed prone and anti-gravity hugging exercises to improve the low trunk tension. Breastfeeding evaluation began 56 days after birth, when the respiratory condition improved. We practiced feeding the infant orally, in collaboration with doctors and nurses, to reduce bending and stabilize the posture when raising the mandible. The infant was gradually able to feed orally and gained weight. Thereafter, he was discharged 141 days after birth. This report concluded that rehabilitation intervention from the neonatal period, in collaboration with the multidisciplinary team and patient's family, contributed to initiation of oral feeding, improvement of sensorimotor development, and smooth transition to home care.

Effect of ionizing radiation on the occupational health of radiologists / 中国辐射卫生

Objective To analyze peripheral blood hemogram, lymphocyte micronucleus and chromosomal aberrations of radiologists, so as to provide basis for occupational protection and health monitoring of radiologists. Methods Lymphocyte micronucleus, chromosome and blood hemogram analysis were performed on 127 radiologists who received health examinations in 2015, 2017 and 2019, and they were assigned to the radiation group. In addition, 133 medical staff with no history of radiation exposure were selected as the control group. Results The micronucleus rate and chromosome aberration rate of the radiation group were higher than those of the control group, and the white blood cell and platelet counts were lower than those of the control group, both of which were statistically significant (P < 0.05). The total number of white blood cells in peripheral blood of 127 radiologists decreased gradually with the increase of exposure time to ionizing radiation, and the chromosome aberration rate increased gradually, all of which had statistical significance (P < 0.05). The rate of chromosomal aberration was higher in radiologists with damage work age of more than 20 years than in the low-work age group, and there was no statistical significance between different damage work age (P > 0.05). The chromosome aberration rate of nuclear medicine and interventional therapy was higher than that of other types, with statistical significance (P < 0.05). Conclusion Long-term exposure to low-dose ionizing radiation can reduce the total number of white blood cells and increase the chromosome aberration rate of radiologists. It is necessary to strengthen the protective measures for radiologists to reduce the degree of ionizing radiation damage, especially to strengthen the occupational protection for radiologists in nuclear medicine and interventional therapy.

A Report of Two Cases in which Kampo Treatment Could Contribute to the Improvement of Quality of Life for Children with Congenital Disorders / 日本東洋医学雑誌

We report two cases in which the quality of life of children with chromosomal aberration improved with Kampo treatment. Case 1 : Six-year-old boy with 5p deletion syndrome. We prescribed kambakutaisoto for the purpose of treating excitability and insomnia. After adding shokenchuto, and further using with yokukansan, the degree of excitement was obviously reduced, and he began to sleep well until morning. Case 2 : Two-year-old boy with chromosome 8 abnormality. He had failed extubation after thoracotomy, thus he needed tracheostomy and gastrostomy. Frequent sputum suction was required every 5 to 15 minutes, and he suffered chronic diarrhea. The number of suctioning was decreased after treatment with bukuryoingohangekobokuto. Moreover, after the addition of shokenchuto, suction became unnecessary for more than 2 hours, and diarrhea also improved. After surgery to close tracheostomy site, he has been receiving ogikenchuto + shoseiryuto + ninjinto and is very well enough to go to a nursery school. Although it is a small improvement not involved in life prognosis, it has contributed to the improvement of the quality of life and the reduction of burden on caregivers. We believe that it is one of the significance of providing Kampo treatment for children.

Biodosimetry estimation of a case of large area back skin injury caused by accidental irradiation in interventional procedure / 中华放射医学与防护杂志

Objective:To evaluate biological dose and retrospective biodosimetry of a case of large area back skin injury caused by suspected interventional procedure.Methods:Peripheral blood from the patient was collected at about 7 months after interventional procedure, and the chromosomal aberrations in peripheral blood cells were analyzed to evaluate the retrospective biodosimetry using the correction factor of dose estimation, Dolphin′s model and Qdr method, respectively. Results:Based on the amounts of semi-automated dic and manually detected dic plus ring, the whole-body average absorbed dose of the victim was estimated to be 0.68-0.95 Gy by four different dose response curves. Over dispersion of dic or dic plus ring was also detected, and the efficiency of dose assessment was obviously increased using dic semi-automatic detection. Based on three different retrospective biodosimetry models, the estimated average absorbed dose was further corrected to be between 1.80-2.86 Gy, which was consistent with clinical diagnosis of degree Ⅳ radiation skin injury.Conclusions:A case of suspected radiation skin injury was confirmed by chromosomal aberration analysis and it’s biodosimetry was reconstructed, suggesting that the unstable chromosomal aberration analysis may be applicable to assess the retrospective biodosimetry of non-uniform local radiation exposure.

Nevus verrugoso gigante con componente angiomatoso cavernoso. Presentación de un caso / Giant Warty Nevus with Cavernous Angioma Component. Case Presentation

RESUMEN El nevus verrugoso es una hiperplasia benigna y congénita de la epidermis superficial y los anexos. Se considera un hamartoma derivado del ectodermo, posiblemente ocasionado por una aberración cromosómica localizada en el brazo largo del cromosoma 1. Se presenta el caso de un paciente de sexo masculino, de 3 años de edad, portador de nevus verrugoso gigante con componente angiomatoso cavernoso, en región occipital, sin otras anomalías. Se utilizaron los datos provenientes de fuentes documentales (carné obstétrico, carné pediátrico, historias clínicas hospitalaria y ambulatoria), exámenes de laboratorio e imagenológicos, así como información obtenida a partir de la entrevista a la madre, para describir la evolución desde el nacimiento. Se realizó búsqueda bibliográfica y se comentan aspectos relacionados con la incidencia, localizaciones, edad de presentación, las características clínicas e histopatológicas, el tratamiento y la evolución. Se realiza este reporte por la baja frecuencia de esta patología en el Hospital Pediátrico General Luis Ángel Milanés de Bayamo, Granma.

ABSTRACT The warty nevus is a benign and congenital hyperplasia of the superficial epidermis and the annexes. It is considered a hamartoma derived from the ectoderm, possibly caused by a chromosomal aberration located on the long arm of chromosome 1.The case of a 3 year-old male patient is presented, with a giant warty nevus with an angioma cavernous component in the occipital region, without other anomalies. Data from documentary sources (such as obstetric card, pediatric card and hospital and outpatient medical records), laboratory and imaging tests, as well as information obtained from the mother's interview, were used to describe the evolution from birth. Issues related to the incidence, locations, age of presentation, clinical and histopathological characteristics, treatment and evolution are discussed, on the bases of a bibliographic search. This report is made due to the low frequency of this pathology at the Paquito González Cueto de Cienfuegos University Pediatric Hospital.

Genotoxicity evaluation of Wentilactone A / 药学实践杂志

Objective To evaluate the genetic toxicity of Wentilactone A. Methods The classical genotoxicity test combination (Ames test, in vitro CHO cell chromosome aberration test and mouse bone marrow micronucleus test) was used to detect the genotoxicity of Wentilactone A. Results Ames test suggested that Wentilactone A was not mutagenic against Salmonella typhimurium with or without the metabolic activation system (S9) at five doses of 5 000, 500, 50, 5, and 0.5 μg/dish. CHO cell chromosome aberration test suggested that the CHO cells cultured in 4 h and 24 h did not induce chromosomal aberrations in three dose groups at the final concentration of 23.74, 47.48, 94.96 μg/ml, with and without S9. The mouse bone marrow micronucleus test showed no significant difference in the bone marrow micronucleus induction rate of cells at three doses of 100, 200, and 400 mg/kg treated for 24 h and at dose of 400 mg/kg treated for 48 h compared with the solvent control group (P>0.05). Conclusion These results indicated that Wentilactone A did not exhibit genetic toxicity based on the Ames test, CHO chromosomal aberration test and micronucleus assay. It was suggested that Wentilactone A had no genetic toxicity and potential carcinogenicity.

Evaluation genotoxicity of acetylnerolin based on quantitative structure-activity relationship model and in vitro tests / 中国药理学与毒理学杂志

OBJECTIVE To evaluate the genotoxicity of naproxen (NPX) impurities acetylnerolin (Ace). METHODS The genotoxicity of Ace was predicted by ADMET, Derek and Sarah with the quanti?tative structure-activity relationship (QSAR). The chromosomal aberration and bacterial reverse-muta?tion (Ames) tests were performed to verify the above results. In chromosomal aberration tests, CHL cells were incubated with Ace 10, 20 and 40 mg · L-1 for 4 h in the presence or absence of metabolic activation system solution (S9 mix). Methyl methane sulfonate (MMS) 20 mL · L-1 without S9 mix and cyclophosphamide (CP) 12 mg · L-1 with S9 mix served as positive control. The number of chromo?somes in each aberrant metaphase (including fissure, exchange, ring, break and polyploid) was counted and recorded, when the distortion rate less than 5％was considered negative and more than 10％was considered positive. In Ames test, the potential mutagenicity was evaluated using five strains of S. typhimurium ( TA97,TA98,TA100,TA102 and TA1535). They were treated with Ace 5, 25, 125 and 625μg per plate with or without S9 mix and incubated for 48-72 h. When without S9 mix, Dexon 50μg per plate served as positive control for TA97 and TA98, MMS 2.0μL per plate served as positive control for TA100 and TA102, and sodium azide 1.5μg per plate served as positive control for TA1535. When with S9 mix, 2-AF 100 μg per plate served as positive control for TA97, TA98 and TA100, 1, 8-dihydroxyanthraquinone (100μg per plate) served as positive control for TA102 and CP 50μg per plate served as positive control for TA1525. When the number of colonies was at least two-fold that of the negative control, the compound was considered mutagenic. RESULTS Although the Derek and Sarah software predicted that the NPX impurities were not genotoxic, ADMET data showed that Ace could induce chromosomal aberrations. The distortion rate of Ace 40 mg · L-1 was greater than 5％, but less than 10％. The distortion rate of Ace was less than 5％when<20 mg·L-1. Consistent with the results of ADMET, Ace might induce chromosomal aberrations. Ames test results showed that Ace did not signifi?cantly increase the number of bacteria (5-625μg per plate) compared with the negative control. Contrary to the ADMET results, Ace had no mutagenicity. CONCLUSION Ace has potential chromosomal muta?genicity. For life-long usage of NPX, the content of Ace should be reduced from 0.15％of conventional impurities to 0.015％.

Mutagenicity, antioxidant activity and nutritional content of long-life tomato / Mutagenicidade, atividade antioxidante e conteúdo nutricional de tomate longa vida

The increasing tomato demand for the food market motivates improvements and the use of new biotechnologies in this fruit's production. The hybrid crop stands out for fruit production resistant to rot and postharvest wilt (long-life crops). Within this context, consumption of genetically modified food deserves attention regarding the safety and nutritional aspects due to the fact that inclusion and/or overexpression of genetic traits can cause harm to human health in the short or long term. In this scenario, this study aimed to evaluate genotoxicity and mutagenicity from different varieties of long-life tomatoes obtained by genetic breeding and also determines main bioactive compounds and antioxidant activity. The genotoxicity and mutagenicity were analyzed via the micronucleus test and the evaluation of chromosome aberrations in mice bone marrow respectively. We have also analyzed carotene, beta-carotene, lycopene, total phenol and flavonoid contents via spectrophotometry and antioxidant activity via DPPH radical scavenging assay. Considering the results obtained, it is possible to conclude that despite the absence of significant genotoxic activity among the evaluated samples, the antioxidant activity and the differences found in composition seems to be ruled by genetic factors, possibly due to the genetic breeding.

O aumento da demanda na produção de tomate para o mercado alimentício vem incentivando transformações e implementações de novas biotecnologias na produção desse fruto, destacando-se a utilização cultivares híbridas que produzem frutos com maior resistência ao fenecimento e apodrecimento após colheita (cultivares do tipo longa vida). Dentro deste contexto, sabe-se que o consumo de alimentos oriundos de melhoramento genético necessita de atenção no aspecto de segurança alimentar e poder nutricional, pois a inclusão e/ou super expressão de características genéticas de interesse pode acarretar a curto ou em longo prazo danos à saúde humana. Neste cenário, o presente estudo teve como objetivo avaliar a genotoxicidade e mutagenicidade de diferentes variedades de tomates do tipo "longa vida" obtidos por melhoramento genético, assim como determinar seus principais compostos bioativos e atividade antioxidante. A genotoxicidade e mutagenicidade foram analisados por meio do teste do micronúcleo e pela avaliação de aberrações cromossômicas em medula óssea de camundongos. Foram determinados caroteno, betacaroteno, licopeno e o conteúdo de polifenóis e flavonoides totais por meio espectrofotométrico e atividade antioxidante pelo método do sequestro do radical DPPH. Diante dos resultados obtidos foi possível concluir que apesar da ausência de atividade genotóxica significativa entre as amostras avaliadas, as diferenças na composição e bioatividade antioxidante observadas no presente estudo, parecem ser governados por fatores genéticos, possivelmente provenientes do melhoramento genético realizado.

Genotoxicity evaluation of triptolide / 药学实践杂志

Objective To study the genotoxicity of triptolide ,an important active component of Tripterygium wilfordii Hook f .Methods Ames test ,in vitro chromosomal aberration test of CHO cell and in vivo micronucleus assay were per-formed to investigate the genotoxicity of triptolide .Results The Ames test showed that triptolide did not increase mutagenicity for TA97 ,TA98 ,TA100 ,TA102 and TA1535 strains at the dosage of 1 .6~1000 μg per plate with and without metabolic ac-tivation system S9 .Results of in vitro CHO cell chromosomal aberration test indicated that there was no statistical difference between the triptolide groups (doses of 0 .01 ,0 .02 and 0 .04 μg/ml) and the solvent control group with and without metabolic activation system S9 .However ,triptolide significantly increased polychromatophilic erythrocyte micronucleus formation at the dosage of 720 μg/kg in ICR mice .Conclusion Triptolide did not induce genetic toxicity based on the Ames test and chromo-somal aberration test ,but could increase micronucleus formation at the dosage of 720 μg/kg .These results indicated that trip-tolide may have potential genotoxicity on human health .

Microirradiation techniques in radiobiological research.

The aim of this work is to review the uses of laser microirradiation and ion microbeam techniques within the scope of radiobiological research. Laser microirradiation techniques can be used for many different purposes. In a specific condition, through the use of pulsed lasers, cell lysis can be produced for subsequent separation of different analytes. Microsurgery allows for the identification and isolation of tissue sections, single cells and subcellular components, using different types of lasers. The generation of different types of DNA damage, via this type of microirradiation, allows for the investigation of DNA dynamics. Ion microbeams are important tools in radiobiological research. There are only a limited number of facilities worldwide where radiobiological experiments can be performed. In the beginning, research was mostly focused on the bystander effect. Nowadays, with more sophisticated molecular and cellular biological techniques, ion microirradiation is used to unravel molecular processes in the field of radiobiology. These include DNA repair protein kinetics or chromatin modifications at the site of DNA damage. With the increasing relevance of charged particles in tumour therapy and new concepts on how to generate them, ion microbeam facilities are able to address unresolved questions concerning particle tumour therapy.

Evaluation of Anticlastogenic effects of Glycyrrhiza glabra root extract against Cyclophosphamide induced Chromosomal aberration in Swiss albino Mice.

Background: Indian subcontinent is a vast repository of medicinal plants that are used in traditional medical treatments. Various indigenous systems such as Siddha, Ayurveda, Unani and Allopathy use several plant species to treat different ailments. Ayurveda includes diet and herbal remedies, while emphasizing the body, mind and spirit in disease prevention and treatment. Since origin of human’s life, medicinal plants continue to play a curative and therapeutic role in preserving human health against disease. Herbal plants have been a rich source of medicines because they produce a host of bioactive molecules, most of which probably evolved as chemical defenses against predation or infection. Objective: The study was aimed towards evaluation of Immuno-enhancing potential of hydromethanolic root extract of Glycyrrhiza glabra through the prevention of Mutagenecity caused by Clastogenic or Chemotherapeutic agents in bone marrow cells of Swiss albino mice. Methods: For the assessment of Anti-clastogenic efficacy of G. glabra hydromethanolic root extract, the Bone marrow Chromosomal aberration assay was used and the single i.p. of G. glabra extract given at the doses of 300, 450 and 600mg/kg body weight, 24 hours prior the administration of Cyclophosphamide at the dose of 50 mg/kg body wt. Results: The present investigation revealed that, the doses of 450 and 600mg/kg body wt. provided significant protection against Cyclophosphamide induced Chromosomal aberration in the bone marrow cells of Swiss albino mice. A dose dependent inhibition was observed which was statistically significant (p<0.05) when compared to Cyclophosphamide group. It was observed that G. glabra root extract alone has not induced any Chromosomal aberration. Conclusion: Thus in Mutagenecity assay, G. glabra root extract possess protective potential against Cyclophosphamide induced Mutagenecity in mouse Bone marrow cells. It may be concluded that this herbal extract have Anti-clastogenic agents which showed Anti-mutagenic nature.

Docosahexaenoic Acid Reduces Cyto-Genotoxicity of Cytosine Arabinoside in Normal Mouse Bone Marrow.

Aims: This paper evaluates the use of percentage of micronucleus (MN), polychromatic erythrocytes (PCEs), chromosomal aberration (CA) and mitotic index (MI) frequencies in mice bone marrow smears as a method for assessing the ability of docosahexaenoic acid (DHA, is an omega-3 fatty acid) to reduce cyto-genotoxicity damage of cytosine arabinoside (ara-C). Ara-C is widely prescribed antineoplastic drug, especially for the treatment of acute myeloid leukemia. It is a pyrimidine analog, in which the ribose sugar of cytidine is replaced by arabinose moiety. Methodology: Positive control group of mice was only given intraperitoneal dose of ara- C of 75 mg/kg (every 12 h for 5 days); this dose was selected in accordance with its human therapeutic values. Negative control group of mice group only received 0.1 ml sterile distilled water every 12 hours for 5 days. Three treatment groups of mice were given same dose of ara-C in addition to three different doses of DHA (125, 250 and 500 mg/kg of mice). Experimental data were analyzed using (Mann–Whitney U-test) to compare values of positive and negative controls. However, Kruskal–Wallis test followed by Dunn’s multiple comparisons test were used to compare values of treatments with positive control. All values were accepted at p = 0.05. Results: When 75 mg/kg ara-C was applied, positive control group showed a significant increase in MN and CA, a high decrease in PCE, and a significant decrease in MI. When DHA was used with ara-C, the picture is changed, particularly at a medium dose of DHA of 250 mg/kg where a decrease MN and CA and an increase in PCEs in addition to an increase in MI were observed. Conclusion: DHA at 250 mg/kg was able to reduce cytogenotoxicity of ara-C, and lead to protecting the normal proliferating cells in bone marrow from the damaging effect of ara-C and hence improving therapy by ara-C.

Investigation of protective effects of Erythrina velutina extract against MMS induced damages in the root meristem cells of Allium cepa

Erythrina velutina Willd., Fabaceae, is a medicinal plant that can be found in the tropics and subtropics, including in the semi-arid northeastern Brazil. It is commonly used in folk medicine to treat anxiety, agitation and insomnia. E. velutina has been known to present analgesic, anti-inflammatory and antibacterial activities, however, it is unknown if this plant present a protective effect on DNA. We assessed the antigenotoxic effect of E. velutina against the genotoxic effects induced by MMS in the root meristem cells of Allium cepa. Three concentrations of the aqueous extract (100, 200 and 400 mg/L) of this medicinal plant were used in three different types of treatment (pre-, post- and simultaneous). The effects of the extracts on the root meristem cells of A. cepa were analyzed at both macroscopic and microscopic levels. Protective effects were observed at higher concentrations in pre-treatment and in simultaneous treatment. The results suggest that E. velutina may present antigenotoxic properties and demonstrate its chemopreventive potential.

Cytotoxicity and mutagenicity of cola and grape flavored soft drinks in bone marrow cells of rodents / Citotoxicidade e mutagenicidade de refrigerantes sabor cola e uva, em células de medula óssea de roedor

Due to the large consumption of soft drinks in Brazil and worldwide in recent years and considering that some of the components presentin their composition pose potential risks to human health, the aim of this study was to evaluate the cytotoxic and mutagenic potential ofspecific cola and grape-flavored soft drink brands. Bone marrow cells of Wistar rats were initially treated by gavage with one single dose of Cola or Grape soft drink, which was next offered ad libitum (instead of water) for 24 hours. A negative control treatment was performed by administering one single dose of water and a positive control administering cyclophosphamide intraperitoneally. Statistical analysis showedthat the Cola and Grape soft drinks studied were not cytotoxic. However, the Cola soft drink proved mutagenic in this experiment treatmenttime. Therefore, this study serves as a warning about the consumption of Cola-flavored soft drink and for the need for further subchronicand chronic studies on soft drinks in order to evaluate the long term mutagenic and cytotoxic effects of these substances.

Devido ao grande consumo de refrigerantes no Brasil e no mundo nos últimos anos, e tendo em vista que alguns dos componentes presentes na composição destes possuem potenciais danosos para os organismos, em especial o humano, o objetivo deste trabalho foi avaliar o potencial citotóxico e mutagênico de uma marca de refrigerante sabor Cola e uma de sabor Uva. Foram utilizadas como sistema-teste as células demedula óssea de ratos Wistar, tratados via gavagem com dose única do refrigerante sabor Cola ou Uva e, em seguida, fornecidos ad libitum(no lugar da água), por 24 horas. Foi feito um controle negativo, administrando água, em dose única, e um controle positivo administrando ciclofosfamida, via intraperitoneal. A análise estatística mostrou que os refrigerantes sabor Cola e Uva não foram citotóxicos. Entretanto, o refrigerante sabor Cola foi mutagênico neste sistema-teste e tempo de tratamento. Desta forma, este estudo serve de alerta para o consumo de refrigerantes sabor Cola e indica que estudos subcrônicos e crônicos com os refrigerantes devem ser realizados, a fim avaliar os efeitos mutagênicos e citotóxicos dessas substâncias a longo prazo.

Effects of melatonin on DNA damage induced by cyclophosphamide in rats

The antioxidant and free radical scavenger properties of melatonin have been well described in the literature. In this study, our objective was to determine the protective effect of the pineal gland hormone against the DNA damage induced by cyclophosphamide (CP), an anti-tumor agent that is widely applied in clinical practice. DNA damage was induced in rats by a single intraperitoneal injection of CP (20 or 50 mg/kg). Animals received melatonin during the dark period for 15 days (1 mg/kg in the drinking water). Rat bone marrow cells were used for the determination of chromosomal aberrations and of formamidopyrimidine DNA glycosylase enzyme (Fpg)-sensitive sites by the comet technique and of Xpf mRNA expression by qRT-PCR. The number (mean ± SE) of chromosomal aberrations in pinealectomized (PINX) animals treated with melatonin and CP (2.50 ± 0.50/100 cells) was lower than that obtained for PINX animals injected with CP (12 ± 1.8/100 cells), thus showing a reduction of 85.8% in the number of chromosomal aberrations. This melatonin-mediated protection was also observed when oxidative lesions were analyzed by the Fpg-sensitive assay, both 24 and 48 h after CP administration. The expression of Xpf mRNA, which is involved in the DNA nucleotide excision repair machinery, was up-regulated by melatonin. The results indicate that melatonin is able to protect bone marrow cells by completely blocking CP-induced chromosome aberrations. Therefore, melatonin administration could be an alternative and effective treatment during chemotherapy.

Genotoxicity Assessment of Erythritol by Using Short-term Assay

Erythritol is a sugar alcohol that is widely used as a natural sugar substitute. Thus, the safety of its usage is very important. In the present study, short-term genotoxicity assays were conducted to evaluate the potential genotoxic effects of erythritol. According to the OECD test guidelines, the maximum test dose was 5,000 microg/plate in bacterial reverse mutation tests, 5,000 microg/ml in cell-based assays, and 5,000 mg/kg for in vivo testing. An Ames test did not reveal any positive results. No clastogenicity was observed in a chromosomal aberration test with CHL cells or an in vitro micronucleus test with L5178Y tk +/- cells. Erythritol induced a marginal increase of DNA damage at two high doses by 24 hr of exposure in a comet assay using L5178Y tk +/- cells. Additionally, in vivo micronucleus tests clearly demonstrated that oral administration of erythritol did not induce micronuclei formation of the bone marrow cells of male ICR mice. Taken together, our results indicate that erythritol is not mutagenic to bacterial cells and does not cause chromosomal damage in mammalian cells either in vitro or in vivo.

Evaluation of genotoxicity of Trois through Ames and in vitro chromosomal aberration tests

Objective: To investigate the mutagenic potential of Trois using the bacterial reverse mutation assay (Ames test) and in vitro chromosomal aberration test.Methods:typhimurium (TA 98, TA100, TA1535 and TA1537) and Escherichia coli (WP2 uvrA) with and without metabolic activation system (S9 mix) at the dose range of 313 to 5000 μg/plate. Chromosomal aberrations were evaluated in Chinese hamster lung (CHL) cell line at the dose levels of 15, 7.5, 3.7, 1.9 and 0.9 mg/mL in the absence and presence of S9 mix.Results:The ability of Trois to induce reverse mutations was evaluated in Salmonella Trois used in the study with and without S9 mix in all tester strains. Trois did not produce any structural aberration in CHL cells in the presence or absence of S9 mix. There were no increases in the number of revertant colonies at any concentrations of Conclusions: Results of this study suggest that Trois is non-mutagenic.

Genotoxicity of benzene in mammalian cells (Rattus rattus) and its minimization by medicinal plant extracts and Vitamin C.

Benzene is an enlisted industrial carcinogen with genotoxic effects. The present work was aimed at studying the genotoxic effects (chromosomal aberrations and mitotic index changes) of benzene on somatic (bone marrow) cells of 10–15 week old albino rats (Rattus rattus). Many medicinal plants and vitamins are known to have antioxidant and anticlastogenic properties. Therefore, vitamin C and crude extracts of fruits of medicinal plants Phyllanthus emblica (Amla) and Allium sativum (garlic) cloves were tested for their comparative effectiveness in minimizing the genotoxicity of benzene. Genotoxicity of benzene was investigated at doses of 1/ 40, 1/20, 1/10, 1/5 oral LD50. Antioxidants vitamin C (10 mg/kg b.wt) and crude medicinal plant extracts (P. emblica=1000mg/kg b.wt., A. sativum=1000mg/kg b.wt.) were tested for their ability to minimize genotoxic effects of benzene (at 1/10 LD50 dose), at pre, concurrent and post treatment levels. Statistical analysis was done by ‘student t-test’. Benzene was observed to cause significant increase in number of chromosomal aberrations, percentage of aberrated cells and depression in mitotic-index. P. emblica, A. sativum extracts, and vitamin C significantly reduced all the types of observed abnormalities induced by benzene. They showed best results during pre-treatment. Genotoxicity of benzene was best minimized by A. sativum extract. P. emblica and vitamin C showed more or less similar results. Thus, the daily intake of A. sativum extract might prove to be beneficial in minimizing and providing protection against benzene genotoxicity.