A fast chemiluminescent method for H(2)O(2) measurement in exhaled breath condensate

BACKGROUND

Breath condensate can give useful information on volatile compounds produced at alveolar level. Actual concentration of H(2)O(2) in breath condensate is dependent on its production at alveolar level and on the efficacy of the detoxifying systems, catalase, glutathione peroxidase, etc.

METHODS

In the present paper, a simple chemiluminescent method for the determination of the H(2)O(2) collected in exhaled breath is shown and data of both smokers and nonsmokers volunteers are presented.

RESULTS

The chemiluminescent response is linear up to 100 micromol/l H(2)O(2). The analytical sensitivity is about 0.01 micromol/l. Most of the nonsmokers have a H(2)O(2) content lower than 0.05 micromol/l, while smokers have a content ranging from 0.1 to 0.6 micromol/l.

DNA aneuploidy and high proliferative activity but not K-ras-2 mutations as independent predictors of clinical outcome in operable gastric carcinoma: results of a 5-year Gruppo Oncologico dell'Italia Meridonale (GDIM) prospective study

BACKGROUND

The prognostic value of DNA ploidy, S-phase fraction (SPF) and K-ras-2 mutations in gastric carcinoma (GC) has not yet been clearly defined. The aim of this study was to clarify the association between biomolecular variables, tumor characteristics, and clinical outcome in GC patients.

METHODS

Resected specimens from a consecutive series of 69 patients with GC who underwent potentially curative surgery were studied prospectively. DNA ploidy and SPF were assessed by flow cytometry on multiple frozen tumor samples, whereas K-ras-2 mutations were detected by polymerase chain reaction followed by single-strand conformation polymorphism. All the patients involved in this study were followed up for a mean of 95 months.

RESULTS

DNA aneuploidy was present in 72% of the cases (50 of 69), whereas 10% of these (5 out of 50) showed multiclonality. Mutations of K-ras-2 were detected in 8% of the tumors (5 of 63). Both DNA ploidy and SPF were associated with TNM stage (American Joint Committee on Cancer [AJCC] staging system) and node status. Moreover, DNA aneuploidy was significantly related to high SPF. K-ras-2 mutations were not associated with clinicopathologic variables or flow cytometric indicators. At univariate analysis, advanced TNM stage, node involvement, diffuse histotype, depth of invasion, DNA aneuploidy, and high SPF proved to be significantly related to quicker tumor relapse and to shorter overall patient survival. With multivariate analysis, DNA aneuploidy, high SPF, and depth of invasion were related to risk of tumor relapse and patient death, whereas diffuse histotype was independently related to patient risk of tumor relapse.

CONCLUSIONS

DNA ploidy and SPF, when associated with clinicopathologic staging, might be useful for the identification of GC patients who have different risks for death or relapse of disease.

Usefulness of L-carnitine, a naturally occurring peripheral antagonist of thyroid hormone action, in iatrogenic hyperthyroidism: a randomized, double-blind, placebo-controlled clinical trial

Old studies in animals and unblinded studies in a few hyperthyroid patients suggested that L -carnitine is a periferal antagonist of thyroid hormone action at least in some tissues. This conclusion was substantiated by our recent observation that carnitine inhibits thyroid hormone entry into the nucleus of hepatocytes, neurons, and fibroblasts. In the randomized, double-blind, placebo-controlled 6-month trial reported here, we assessed whether 2 or 4 g/d oral L-carnitine were able to both reverse and prevent/minimize nine hyperthyroidism- related symptoms. We also evaluated changes on nine thyroid hormone-sensitive biochemical parameters and on vertebral and hip mineral density (bone mineral density). Fifty women under a fixed TSH-suppressive dose of L -T(4) for all 6 months were randomly allocated to five groups of 10 subjects each. Group 0 associated placebo for 6 months; groups A2 and A4 started associating placebo (first bimester), substituted placebo with 2 or 4 g/d carnitine (second bimester), and then returned to the association with placebo. Groups B2 and B4 started associating 2 and 4 g/d carnitine for the first two bimesters, and then substituted carnitine with placebo (third bimester). Symptoms and biochemical parameters worsened in group 0. In group A, symptoms and biochemical parameters worsened during the first bimester, returned to baseline or increased minimally during the second bimester (except osteocalcin and urinary OH-proline), and worsened again in the third bimester. In group B, symptoms and biochemical parameters (except osteocalcin and urinary OH-proline) did not worsen or even improved over the first 4 months; they tended to worsen in the third bimester. In both the A and B groups, the two doses of carnitine were similarly effective. At the end of the trial, bone mineral density tended to increase in groups B and A (B > A). In conclusion, L-carnitine is effective in both reversing and preventing symptoms of hyperthyroidism and has a beneficial effect on bone mineralization. Because hyperthyroidism depletes the body deposits of carnitine and since carnitine has no toxicity, teratogenicity, contraindications and interactions with drugs, carnitine can be of clinical use.

[Enlarged translabyrinthine approach in large acoustic neurinomas]

The translabyrinthine approach has long been, and in some centers is still, considered inadequate for the removal of large acoustic neuromas (AN). Over the years, with experience, the original technique has been modified, extending the approach to what is now called the enlarged translabyrinthine (ET) approach. Applying these modifications, between April 1987 and February 2000, the Gruppo Otologico in Piacenza, Italy removed 132 ANs, 3 cm or larger, from the cerebello-pontine angle. These tumors accounted for 25.9% of the 510 cases of AN to undergo surgery during that period. Of the 132 cases only one patient died and the percentage of complications was very low, generally lower than analogous series published in the literature. Such complications were progressively reduced in time, leading to a significant reduction in the length of post-operative hospitalization: on the average the 8.8 days were reduced to 5.7 in the last 43 cases. Ipsilateral preoperative hearing, inevitably sacrificed using the ET approach, was already significantly compromised in more than 65% of the cases. On the basis of the present data, it can be asserted that tumor diameter does not in any way preclude the use of the ET approach in AN surgery, rather the reduced morbility and shorter post-operative hospitalization make it the approach of choice for large ANs.

[Unifocal skin location of Kaposi's sarcoma, mimicking melanoma: the role of excisional biopsy for the timely identification of an unusual pathology with potential fatal prognosis]

Kaposi's sarcoma is a mesenchimal malignant tumor with a very low incidence. Generally arising with purple cutaneous lesions, especially located to the limbs or the trunk, it's significantly associated to myelodeficient disorders, either primary or subsequent to viral infections, whose terminal stage it is considered (AIDS). Unique lesion in sporadic disease, without any other pathologies and at early stage, it has its elective treatment in surgical excision, just as in the reported case emphasizing the necessity for differential diagnosis with another malignant oncological disease, such as melanoma.

[Early diastolic sound in a patient with hepatocarcinoma]

On physical examination an early diastolic sound is usually associated with mitral stenosis, prosthetic mitral valve replacement and chronic constrictive pericarditis. In case of an atrial myxoma, an early diastolic sound can be usually heard due to movement of the tumor towards the tricuspid valve (tumor plop). The following case report shows an example in which an early diastolic sound was heard in a patient presenting with a hepatocellular carcinoma. This sound was due to the presence of a thrombus that originated from the inferior vena cava and invaded the right atrium up to the tricuspid valve. It was thus similar to an atrial myxoma and produced a tumor plop.

Branching projections of catecholaminergic ventrolateral reticular neurons to the fastigial nucleus and superior colliculus in the rat: triple labelling procedure

In this study, we employed triple fluorescent-labelling to reveal the distribution of the catecholaminergic neurons within rostral ventrolateral reticular nucleus which supply branching collateral input to the superior colliculus (SC) and to the cerebellar fastigial nucleus (FN). The catecholaminergic identity of the neurons was revealed by immunocytochemical detection of the biosynthetic enzyme, tyrosine hydroxylase. The projections were defined by injections of two retrograde tracers: rhodamine and fluoro gold in the SC and FN, respectively.

Red meat, family history, and increased risk of gastric cancer with microsatellite instability

Microsatellite instability (MSI) occurs frequently in sporadic gastric cancer (GC) and may define a distinctive molecular pathway of carcinogenesis. We evaluated the role of dietary risk factors in GC according to MSI status. A large series of 382 GC cases and 561 controls were originally identified in a population-based case-control study carried out in the high-risk area around Florence, Italy; 126 GC patients were typed for MSI status. A MSI+ phenotype was detected in 43 of 126 cases (34.1%), whereas 83 cases were classified as MSI-. A multinomial logistic regression model was used to compare the two subgroups of GC classified according to MSI status in the same analysis, with all of the available population controls. A case-case approach was also used. The risk of MSI+ tumors was positively associated with high consumption of red meat and meat sauce and negatively associated with consumption of white meat. A positive association was also seen with total protein and nitrite intake, whereas no relation was found with micronutrient intake. Risk was especially high among subjects reporting both a positive GC family history and a high consumption of red meat (odds ratio, 25.7; 95% confidence interval, 6.4-102.8). For MSI- tumors, a significant protective effect was associated with frequent consumption of citrus and other fresh fruit, garlic, legumes, vegetables, and olive oil and with high intake of beta-carotene and other antioxidants and sugar, whereas positive associations were seen with protein and sodium intake. In summary, a specific dietary pattern emerged for MSI+ gastric tumors, suggesting that factors related to red meat consumption are involved in this pathway, particularly among individuals with a positive family history. In contrast, the risk of MSI- tumors was strongly reduced by the frequent consumption of fresh fruit and vegetables.

DNA aneuploidy and high proliferative activity but not K-ras-2 mutations as independent predictors of clinical outcome in operable gastric carcinoma: results of a 5-year Gruppo Oncologico dell'Italia Meridonale (GDIM) prospective study

BACKGROUND

The prognostic value of DNA ploidy, S-phase fraction (SPF) and K-ras-2 mutations in gastric carcinoma (GC) has not yet been clearly defined. The aim of this study was to clarify the association between biomolecular variables, tumor characteristics, and clinical outcome in GC patients.

METHODS

Resected specimens from a consecutive series of 69 patients with GC who underwent potentially curative surgery were studied prospectively. DNA ploidy and SPF were assessed by flow cytometry on multiple frozen tumor samples, whereas K-ras-2 mutations were detected by polymerase chain reaction followed by single-strand conformation polymorphism. All the patients involved in this study were followed up for a mean of 95 months.

RESULTS

DNA aneuploidy was present in 72% of the cases (50 of 69), whereas 10% of these (5 out of 50) showed multiclonality. Mutations of K-ras-2 were detected in 8% of the tumors (5 of 63). Both DNA ploidy and SPF were associated with TNM stage (American Joint Committee on Cancer [AJCC] staging system) and node status. Moreover, DNA aneuploidy was significantly related to high SPF. K-ras-2 mutations were not associated with clinicopathologic variables or flow cytometric indicators. At univariate analysis, advanced TNM stage, node involvement, diffuse histotype, depth of invasion, DNA aneuploidy, and high SPF proved to be significantly related to quicker tumor relapse and to shorter overall patient survival. With multivariate analysis, DNA aneuploidy, high SPF, and depth of invasion were related to risk of tumor relapse and patient death, whereas diffuse histotype was independently related to patient risk of tumor relapse.

CONCLUSIONS

DNA ploidy and SPF, when associated with clinicopathologic staging, might be useful for the identification of GC patients who have different risks for death or relapse of disease.

Functional status and clinical correlates in cognitively impaired community-living older people

We describe the prevalence of cognitive impairment in a population of community-living older people, its association with functional decline, and degree of comorbidity. In addition, we examined the relationship between different levels of cognitive impairment and mortality. We conducted an observational study of 1787 patients aged 65 years and above with any degree of cognitive impairment. Patient data were collected with the Minimum Data Set for Home Care. More than 50% of patients had some level of cognitive impairment, which correlates with the degree of physical frailty. On the contrary, patients with cognitive impairment appear to have fewer comorbid conditions and are less likely to receive medications than patients with normal cognitive status. In particular, hypertension, congestive heart failure, chronic obstructive pulmonary disease, cancer, diabetes mellitus, and osteoporosis are found more frequently among patients with normal mental status compared with those showing some level of cognitive defects. Yet, more severe cognitive impairment is associated with a higher mortality rate. Demented patients are characterized by a high prevalence of functional disability and by increased mortality. This increased morbidity and mortality rate is associated with a lower prevalence of comorbid clinical conditions and drug use, relative to patients with normal cognitive performance. The present findings support the possibility that severe cognitive impairment has an independent effect on survival.

Predictors of delayed gastric emptying in diabetes

OBJECTIVE

To define the predictors of the rate of gastric emptying in patients with diabetes.

RESEARCH DESIGN AND METHODS

A total of 101 outpatients with diabetes (79 type 1 and 22 type 2) underwent measurements of gastric emptying of a solid/liquid meal (scintigraphy), upper gastrointestinal symptoms (questionnaire), glycemic control (blood glucose concentrations during gastric emptying measurement), and autonomic nerve function (cardiovascular reflexes).

RESULTS

The gastric emptying of solid and/or liquid was delayed in 66 (65%) patients. Solid (retention at 100 min 64 +/- 3.2 vs. 50.2 +/- 3.6%, P < 0.005) and liquid (retention at 100 min 22.7 +/- 1.7 vs. 16.0 +/- 1.8%, P < 0.001) gastric emptying was slower in women than in men. Of all upper gastrointestinal symptoms (including nausea and vomiting), only abdominal bloating/fullness was associated with slower gastric emptying (P < 0.005). A multiple regression analysis demonstrated that both abdominal bloating/fullness and female sex were predictors of slower gastric emptying of both solids and liquids.

CONCLUSIONS

We conclude that the presence of abdominal bloating/fullness but not any other upper gastrointestinal symptom is associated with diabetic gastroparesis and that gastric emptying is slower in diabetic women than in diabetic men.

Histopathological features and modulation of type IV collagen expression induced by Pseudomonas aeruginosa lipopolysaccharide (LPS) and porins on mouse skin

BACKGROUND

Pseudomonas aeruginosa (P. aeruginosa) is responsible for serious infections in the immunocompromised host. Many skin lesions induced by P. aeruginosa have been described. Few investigations have been performed on the local action of P. aeruginosa components.

OBJECTIVES

To shed light on the "in vivo" activity of lipopolysaccharide (LPS) and porins extracted from P. aeruginosa, by verifying their effects after inoculation in mouse skin through the observation of histological changes and immunohistochemical expression of collagen IV.

RESULTS

Both substances were able to induce a similar inflammatory process and a characteristic reversible change in collagen IV distribution. Interestingly, a fibroblast increase was observed at 24 h in the skin treated with porins, while it appeared later in the skin treated with LPS. Besides these changes, porins particularly increased collagen edema, together with disgregation of hypodermal structures. Moreover "in vitro", porins were able to stimulate fibloblasts 3T3 to convert 72 kDa type IV collagenase into the activated 62 kDa form and to release the 92 kDa collagenase.

CONCLUSION

LPS and porins, released by gram-negative bacteria during cell growth and lysis, interact with the host at target cells, such as keratinocytes, fibroblasts and immunocompetent cells, thus contributing significantly to the pathogenesis of P aeruginosa skin infections.

Effect of lifestyle, smoking, and diet on development of intestinal metaplasia in H. pylori-positive subjects

OBJECTIVES

This study aimed to evaluate the influence of environmental and sociodemographic factors and the effect of smoking, alcohol, and dietary habits on the risk of gastric intestinal metaplasia (IM) in Helicobacter pylori-infected subjects.

METHODS

The investigation was based on 2598 consecutive volunteer blood donors tested for the presence of antibodies against H. pylori from March 1995 to March 1997. Endoscopy with multiple biopsies was offered to all H. pylori-positive, symptomatic subjects. The presence or absence of IM was diagnosed by gastric biopsies. A serologically H. pylori-positive subject with gastric IM was defined as a case, whereas serologically H. pylori-positive subjects without IM were used as controls. All patients answered a detailed questionnaire collecting sociodemographic characteristics and smoking, alcohol drinking, and dietary habits. Odds ratios (ORs) and their 95% CIs were estimated by unconditional logistic regression, including terms for age and sex, to assess the association between the data collected and IM.

RESULTS

Three hundred forty-four subjects with serological H. pylori infection and upper-GI symptoms underwent GI endoscopy, during which biopsies were taken for histological diagnosis. Histology revealed metaplasia in 74 subjects (21.5%). Incomplete IM was found in 37.8% of these cases. No significant associations were found between IM and anthropometric or sociodemographic factors. There was a significant association between age and IM (chi2 for trend, 6.67; p value, 0.009). Current smokers of over 20 cigarettes per day had a 4-fold risk of IM (OR, 4.75, 95% CI, 1.33-16.99). A 2-fold increased risk was found for high butter consumers (OR, 2.17; 95% CI, 1.14-4.11). No significant specific associations were found between the variables studied and complete or incomplete IM.

CONCLUSIONS

This study found that smoking and high butter consumption may increase the risk of having gastric IM in H. pylori-positive subjects.

A weekly regimen of cisplatin, paclitaxel and topotecan with granulocyte-colony stimulating factor support for patients with extensive disease small cell lung cancer: a phase II study

The present study was aimed at defining the antitumour activity of the cisplatin-paclitaxel-topotecan (CPT) weekly administration with G-CSF support in chemo-naive SCLC patients with extensive disease (ED-SCLC). Chemonaive ED-SCLC patients received cisplatin 40 mg/m(2), paclitaxel 85 mg/m(2), and topotecan 2.25 mg/m(2)weekly, with G-CSF (5 microg/kg days 3-5) support, for a maximum of 12 weeks. 37 patients were treated, for a total of 348 cycles delivered. 8 complete responses (22%) and 22 partial responses (59%) were recorded, giving an 81% [95% CI = 65-92%] ORR. At a 13-month (range, 4-26) median follow-up, median progression-free and overall survival were 8 months and 12.5 months, with 1-year and 2-year projected survivals of 55% and 21%, respectively. No toxic deaths occurred. Grade 4 neutropenia and thrombocytopenia occurred in 6 and 3 patients, respectively. Only one case of neutropenic sepsis was recorded, while haemorrhagic thrombocytopenia was never observed. Diarrhoea, paraesthesias and fatigue were the main nonhaematologic toxicities being severe in 6, 2 and 10 patients, respectively. The weekly CPT combination with G-CSF support represents a well tolerated therapeutic approach in chemo-naive ED-SCLC patients. The activity rate seems at least similar to that achievable with the standard front-line approaches.

At term pregnancies in transfusion-dependent beta-thalassemic women

The health background management and outcome of five pregnancies in women affected by Cooley Disease are described and the preconceptual guidance and care are considered. The patients were selected from a group of 103 thalassemic women divided into three subgroups according to their first and successive menstruation characteristics. Only one woman needed induction of ovulation. A precise and detailed pre-pregnancy assessment was done before each conception. All the women were in labour at 38 weeks' gestation, and five healthy babies were born at term, weighing between 2,600 and 3,200 g. The improvement in current treatments will result in a continuous increase in pregnancies in thalassemic women, making pregnancy a real eventuality for them. Furthermore, we are studying the possibility of collecting foetus umbilical cord blood after delivery, with the aim of obtaining complete marrow reconstitution in an attempt at heterologous transplantation to the mother.

Adenomyosis and uterus rupture during labor

A spontaneous uterus rupture occurred during the labour of a 37-week-pregnant woman showing a precocious rupture of membranes. It appeared enlarged and the cut surface of the myometrium showed coarse trabeculations. The histological examination showed a hypertrophic gravidic myometrium with heterogeneous areas of fibrosis and adenomyosis, necrotic decidual foci and hyperplastic cervical canal glands. Our experience suggests that a silent and spontaneous uterine rupture, is possible even in the absence of the principal risk factors.

Antitumor action of seminal ribonuclease, its dimeric structure, and its resistance to the cytosolic ribonuclease inhibitor

Bovine seminal RNase (BS-RNase) is a homodimeric enzyme with a cytotoxic activity selective for tumor cells. In this study, the relationships of its cytotoxic activity to its dimeric structure and its resistance to the cytosolic RNase inhibitor (cRI) are investigated systematically by site-directed mutagenesis. The results show that (1) the dimericity of BS-RNase is essential for its full cytotoxic action; (2) the role of the dimeric structure in the antitumor activity is that of making the enzyme insensitive to the cytosolic RNase inhibitor; (3) a RNase may not be completely insensitive to cRI to exploit a full cytotoxic potential.

Genotype and phenotype factors as determinants of desmoid tumors in patients with familial adenomatous polyposis

Desmoids represent the most important cause of death, after colorectal cancer, in patients affected with familial adenomatous polyposis (FAP), an inherited disease due to mutations in the APC gene. The aims of our study were to estimate the risk of developing desmoids in FAP patients and to evaluate the association between desmoids and different risk factors. The occurrence of desmoids, colorectal cancer and other extra-colonic manifestations were assessed in 897 FAP patients, 653 of whom were also investigated for APC mutations. Odds ratios (OR) and corresponding 95% confidence intervals (CI) were computed using an unconditional multiple logistic regression model. Desmoids developed in 107 patients (11.9%), with a cumulative risk of 20.6%. Females had a significantly higher risk than males (OR = 2.1; 95% CI 1.4-3.1). Family history of desmoids (OR = 8.75; 95% CI 5.66-13.51), osteomas (OR = 2.9; 95% CI 1.8-4.8) and epidermoid cysts (OR = 1.8; 95% CI 1.1-3.2) was also significantly associated with the occurrence of disease. Subjects with APC mutations beyond codon 1444 had a 12-fold increased risk, compared with patients with mutations located upstream. Mutations beyond codon 1309 conferred a 17-fold higher risk, compared with mutations upstream codon 452. Multivariate analysis identified as independent predictors mutation beyond codon 1444 (OR = 6.2; 95% CI 2.5-15.8), family history of desmoids (OR = 5.8; 95% CI 3.1-10.6), female gender (OR = 2.1; 95% CI 1.1-3.8) and the presence of osteomas (OR = 1.9; 95% CI 1.1-3.4). Our results indicate that integrating genetic and clinical data is helpful in defining subgroups of patients at higher risk for desmoids, who may benefit from specific prevention programs.

Preoperative characteristics and postoperative behavior of bowel wall on risk of recurrence after conservative surgery in Crohn's disease: a prospective study

OBJECTIVE

To evaluate in patients with Crohn's disease, using transabdominal ultrasound, the morphologic characteristics of the diseased bowel wall before and after conservative surgery and to assess whether these characteristics and their behavior in the postoperative follow-up are useful and reliable prognostic factors of clinical and surgical recurrence.

SUMMARY BACKGROUND DATA

Ultrasound is effective for evaluating the thickness of bowel wall, the most typical and constant finding of Crohn's disease. No data are currently available concerning the behavior of the diseased intestinal wall after conservative surgery and whether the preoperative characteristics of bowel wall or its behavior after conservative surgery may predict recurrence.

METHODS

In 85 consecutive patients treated with strictureplasty and miniresections for Crohn's disease, clinical and ultrasonographic evaluations were performed before and 6 months after surgery. Assessed before surgery were the maximum bowel wall thickness, the length of bowel wall thickening, the bowel wall echo pattern (homogeneous, stratified, and mixed), and the postoperative bowel wall behavior, classified as normalized, improved, unchanged, or worsened.

RESULTS

A significant correlation was found between a long preoperative bowel wall thickening and surgical recurrence. Bowel wall thickness after surgery was unchanged or worsened in 43.3% of patients; in these patients, there was a high frequency of previous surgery. Patients with unchanged or worsened bowel wall thickness had a higher risk of clinical and surgical recurrence compared with those with normalized or improved bowel wall thickness.

CONCLUSION

With the use of abdominal ultrasound, the authors found that the thickening of diseased bowel wall may unexpectedly improve after conservative surgery, and this is associated with a favorable outcome in terms of clinical and surgical recurrence. In addition to its diagnostic usefulness, ultrasound also provides reliable prognostic information concerning clinical and surgical recurrence in patients with Crohn's disease in the postoperative follow-up.

Analysis of mutational effects at the HPRT locus in human G(0) phase lymphocytes irradiated in vitro with gamma rays

The mutational effects of ionising radiation at the hypoxanthine-guanine phosphoribosyl transferase (HPRT) locus were studied in human peripheral blood G(0) phase lymphocytes irradiated in vitro with gamma rays. The presence of radiation induced mutants was assessed by selecting the HPRT mutants every week on the basis of 6-thioguanine resistance up to 1 month after irradiation. A dose-related increase of 14.25x10(-6) mutants/Gy was measured after an expression time of 7 days. After 2 weeks from culture starting the fraction of clonable cells in irradiated and control cell populations decreased, limiting the measurements of mutant frequency. The mutational spectrum of the HPRT gene was determined by PCR analyses in a total of 99 mutant clones derived from irradiated lymphocytes. The independent origin of mutant clones carrying the same mutation was assessed by analysing the TCR gamma gene rearrangements. The results showed a dose-related increase of deletion mutants up to 3Gy, whereas point mutation frequency increased only up to 2Gy. Two preferentially deleted regions were identified; one involving the HPRT exon 3, and another one the 3'-terminal and the 3'-flanking region of the gene. One complex mutation involving a non-contiguous deletion of exons 2-5 and 7/8 was observed among the mutants isolated after 3Gy irradiation.

Indian medicinal plants as antiradicals and DNA cleavage protectors

Celastrus paniculatus L. (Celastraceae) (CP), Picrorhiza kurroa L. (Scrophulariaceae) (PK) and Withania somnifera L. (Solanaceae) (WS) are Indian medicinal plants having a remarkable reputation, as a factor of health care, among the indigenous medical practitioners. The plants exhibit varying degrees of therapeutic value some of which useful in the treatment of cognitive dysfunction, epilepsy, insomnia, rheumatism, gout, dyspepsia. In this work, we have investigated the free radical scavenging capacity of methanolic extracts from CP, PK, WS and the effect on DNA cleavage induced by H2O2 UV-photholysis. In addition, we investigated whether these plant extracts are capable of reducing the hydrogen peroxide-induced cytotoxicity and DNA damage in human non-immortalized fibroblasts. These extracts showed a dose-dependent free radical scavenging capacity and a protective effect on DNA cleavage; methanolic extracts from PK was more active than extracts from CP and WS. These results were confirmed by a significant protective effect on H2O2-induced cytoxicity and DNA damage in human non-immortalized fibroblasts. These antioxidant effects of active principle of CP, PK and WS may explain, at least in part, the reported anti-stress, immunomodulatory, cognition-facilitating, anti-inflammatory and antiaging effects produced by them in experimental animal and in clinical situations and may justify the further investigation of their other beneficial biological properties.

Bioflavonoids as antiradicals, antioxidants and DNA cleavage protectors

Flavonoids have recently aroused considerable interest because of their broad pharmacological activity. In fact, flavonoids have been reported to have antiviral, antiallergic, antiplatelet, anti-inflammatory and antitumoral activities. The pharmacological properties of bioflavonoids have been ascribed both to the concomitant inhibition of enzymes involved in the production of free radicals and to their free-radical scavenging and iron chelating capacity. However the antioxidant capacity of bioflavonoids due to free-radical scavenging and/or to iron chelating is still controversial. In this study, we have investigated the free-radical scavenging capacity of bioflavonoids (rutin, catechin, and naringin). In addition, the effects of these polyphenols on xanthine oxidase activity, spontaneous lipid peroxidation, and DNA cleavage were investigated. The bioflavonoids under examination showed a dose-dependent free-radical scavenging effect, a significant inhibition of xanthine oxidase activity, and an antilipoperoxidative capacity. In addition, they showed a protective effect on DNA cleavage.