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The effect of Salvadora persica L. stem extracts on the potentiation of sodium pentobarbital activity and on generalized tonic-clonic seizure produced by pentylenetetrazol (PTZ) on the rat is reported. The extracts of Salvadora persica L. extended sleeping-time and decreased induction-time induced by sodium pentobarbital; in addition it showed protection against pentylenetetrazol-induced convulsion by increasing the latency period and diminishing the death rate.

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In Sicily folk medicine, Opuntia ficus indica (L.) Mill. cladodes are used for the treatment of gastric ulcer. We studied the effect of administration of lyophilized cladodes on experimental ethanol-induced ulcer in rat. In this paper, we report the ultrastructural observations of gastric mucosa. The ultrastructural changes were observed by trasmission electronic microscopy (TEM) confirming the protective effect exercised by administration of lyophilized cladodes. Pre-treatment test in rats revealed a protective action against ethanol-induced ulcer. Probably, the mucilage of Opuntia ficus indica is involved.

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We study the phase space region of two- and three-dimensional lattices where a transition from chaotic to ordered dynamics takes place when the energy is lowered. In this region we find coexistence of degrees of freedom (DOF's), endowed with different levels of chaos. The analysis of this complex dynamical pattern requires the introduction of diagnostic tools suitable for a characterization of single DOF's: coherence angles and coherence times. We find that the coherence times-which give a measure of the time each DOF needs to relax to equilibrium-are roughly proportional to the inverse of the specific energy. This may be useful to evaluate the reliability of statistical results obtained in computer experiments performed on condensed matter systems at low energy.

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The effects of chronic intragastric administration of the aerial parts decoction of Teucrium divaricatum Heldr. ssp. divaricatum (Labiateae) on experimental acetylsalicylic acid (ASA)-induced ulcer were studied in rats. The ulcer index and histological mucosa regeneration were evaluated. The ulcer index significantly decreased (U.I. 1.7+/-1.5; P<0.05) after treatment with a lyophilized decoction of T. divaricatum (500 mg/kg os), once daily for 7 days, compared to the control (U.I. 11.4+/-2.3). The ultrastructure modifications of gastric mucosa were observed by transmission electronic microscopy (TEM) confirming the antisecretory effect exercised by administration of the T. divaricatum decoction. Treatment with T. divaricatum seems to block up parietal cell acid secretion and to stimulate in the chief cells the formation of zymogen granules.

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The stem decoction of Salvadora persica L., a drug widely used as a tooth cleaning stick in Arabian countries, shows, in normal rats, hypoglycemic effects, an increase in plasma immunoreactive insulin (IRI) and an incremented oral-glucose tolerance. The decoction also causes a significant decrease in mean body weight without drastic reduction in food consumption.

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The effects of chronic intragastric administration of naringin (200 mg/kg) on experimental acetylsalicylic acid (ASA)-induced ulcer were studied in rat. The ulcer index and histological mucosa regeneration were evaluated. The ulcer index significantly decreased after treatment with naringin (200 mg/kg) once daily for seven days. Microscopic observations confirm these results.

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To stimulate therapeutic irradiation, we exposed rats to conventional fractionation (200 +/- 4 cGy/d, 5 d/wk; total dose, 4000 cGy). The effects of this regimen were assessed by electron microscopic examinations of brain microvascular and parenchymal cells 15 and 90 days after irradiation. Studies of the transendothelial passage of horseradish peroxidase provided information about the functional status of the blood-brain barrier. At 15 days after irradiation, there was an increased vesicular transport of horseradish peroxidase across the intact endothelium without opening of the tight junctions, and without evidence of structural alterations of neuropil, neuronal bodies, and astrocytes. Ninety days after irradiation, well-defined ultrastructural alterations were observed, involving the microvasculature, the neuropil, the neuronal bodies, and astrocytes. The main ultrastructural feature of cortical microvessels was their collapsed aspect, associated with perivascular edema containing cell debris. Altered neurons and reactive activated astrocytes were also noticeable. These data suggest a possible association, not necessarily causal, between damage of the microvascular/glial unit of tissue injury and development of radiation-induced brain toxicity.

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The microvasculature of the stroma of four cases of small early gastric cancer (EGC) was investigated by conventional electron microscopy. Severe damage to small and large fenestrated capillaries was observed around endothelium-adherent, partially degranulated neutrophils. The findings suggest the existence of neutrophil-mediated injury of endothelial cells during the development of inflammatory responses in small EGC. The severely injured microvessels exhibited increase in vasopermeability, microhaemorrhage, and platelet aggregates. Other microvascular changes included endothelial cell and pericyte activation as well as basal lamina replications, indicative of repeated episodes of endothelial injury, necrosis and regeneration. This new capillary growth within the old basal laminas shared morphological features with a peculiar angiogenic process described in man and animals.

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Basic mechanisms underlying the tolerance and reaction of the central nervous system to ionizing radiation have not been fully elucidated in the literature. The authors employed the [14C]-2-deoxy-D-glucose autoradiography method to investigate the effect of whole-brain x-irradiation on local cerebral glucose utilization in the rat brain. The animals were exposed to conventional fractionation (200 +/- 4 cGy/day, 5 days/week for a total dose of 4000 cGy), and the effects of this regimen were assessed at 2 weeks and 3 months postirradiation. In rats evaluated 2 weeks after treatment, statistically significant decreases in cerebral metabolic activity were found in 13 of the 27 regions studied, compared to control animals. In rats studied 3 months after treatment, additional metabolic suppression and statistically significant decreases in cerebral metabolic activity were found in 11 of the 27 regions, compared to rats studied 2 weeks after treatment. A weighted-average rate for the brain as a whole was approximately 15% and approximately 25% below that of control animals 2 weeks and 3 months after exposure, respectively. Although the difference in species is significant enough so that direct extrapolation to humans may not be appropriate, the data reported here may have potential clinical implications for the evaluation of the risk-benefit ratio for radiotherapy. This model can be used reproducibly for further investigations, including evaluation of therapies that may reduce irradiation-induced brain injury.

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Previous reports showed Helicobacter pylori (H. pylori) in type B gastritis-affected stomachs. This study was carried out to compare H. pylori staining effectiveness on biopsy to brush cytology. Tissue and brush parallel samples of gastric mucosa with abnormal or normal appearances were examined: 57.6% H. pylori-positive pieces from the antrum and 19.2% from the body were found, versus 65.3% and 25% H. pylori-positive brush smears, respectively. H. pylori resembling organisms were mainly related to chronic and acute antral inflammations and were often associated with higher amounts of round-shaped cocco-bacteria. In addition, H. pylori direct stain on brushing is proposed as the most rapid and reliable method for the routine diagnosis of Helicobacter pylori infection, in both ulcer or nonulcer gastritis.

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The authors report their own experience in obtaining pain relief in 13 recurrent or disseminated cancer patients affected by lumbosacral carcinomatous neuropathy (LCN). The site, where the disease involved the lumbosacral plexus or its branches, was palliatively irradiated with a few large fractions. The average duration of response was 196 days. Median survival (uncensored) was 185 days (range 47-636 days).

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Employing quantitative autoradiography, pineal body glucose utilization (GU) was measured in daytime or at night in prepubertal (aged 1 month), adult (aged 3 months), and mature (over 12 months old) rats. In prepubertal and adult rats, in daytime, GU values within the pineal tissue were homogeneously distributed around 65 mumol glucose/100 g per min. In prepubertal animals no significant variations in GU were observed between daytime and nocturnal measurements. A circadian metabolic rhythmicity was evident in adult rats, with a GU peak measured at 2 a.m. In mature animals, GU also varied between day and night, with an increment in the relative difference between the two values. The present investigation is the first to demonstrate that circadian metabolic rhythmicity is absent before sexual maturation while it is enhanced in 12-month-old rats. These changes in pineal energy metabolism with advancing age are intriguing in view of the concept that the pineal gland may be involved in functional changes occurring during the process of aging.

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The authors report a patient with iatrogenic dissemination of hepatocellular carcinoma (HCC). A 65-year-old Caucasian man was found to have a moderately well-differentiated HCC diagnosed by laparoscopy and biopsy; the patient had atypical left liver lobe resection. Thirty-three months after definitive surgery a double relapse was found at the site of the previous laparoscopy and at the surgical scar; no other metastases were found. Surgical procedure for removal of these lesions was performed, and the patient received complementary radiation therapy. At 30 months of follow-up, the patient is alive and disease free. The risk of neoplastic seeding through biopsy and improved safety in surgical techniques justify the omission of diagnostic biopsy in patients who have surgical procedures.

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We define a solitary pulmonary noncalcified nodule (NPS) as a single focal rounded or ovoid lesion in the lung parenchyma, less than 4 cm in diameter, without associated adenopathy, atelectasis or pneumonia. An NPS, in the absence of a known primary malignancy, can be lung cancer (NPSM), a metastasis of unknown origin (NPSMT), or a benign lesion (NPSB). The best approach to the management of NPS and the value of CT are still controversial and uncertain. The finding on cross-section CT of a bronchus leading directly to, or contained within, the nodule is called "positive CT bronchus sign" (CT-BS). Our study was aimed at investigating the usefulness of CT bronchus sign, as studied on thin-slice (2 mm thick) CT sections, in order to establish the most appropriate diagnostic sequence in patients with solitary noncalcified pulmonary nodules (NPS). We evaluated 47 NPS (9 NPSB, 34 NPSM and 4 NPSMT) with thin-slice CT to detect the presence of CT bronchus sign. Seventeen cases had CT-BS (15 NPSM; 1 NPSB; 1 NPSMT); of them, 13 were diagnosed by means of transbronchial biopsy and brushing (TBB). Only one case (NPSM) of the 30 (19 NPSM; 3 NPSMT; 8 NPSB) without CT-BS, was diagnosed by TBB. TBB was negative in the 9 NPSB. The CT-BS is not pathognomonic of malignancy; in fact, the sign was observed in NPSB (one tuberculoma) too. Our results suggest that the CT bronchus sign is valuable in predicting the success of TBB in malignant solitary pulmonary nodules. On the other hand, it seems to be useless for NPSB. Therefore, to establish the most appropriate diagnostic sequence, thin-section CT should be performed in each patient with peripheral noncalcified lung lesions to plan whether TBB or transthoracic needle aspiration should come next. If biopsy results are poor, either surgery or the "wait and watch for growth" approaches can be suggested. The choice can be guided by the presence of predisposing factors for cancer or infection.

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Basic mechanisms underlying the tolerance and reaction of the central nervous system to ionizing radiation are not known precisely. We investigated the possibility of a change in blood-brain barrier (BBB) function as a causative factor for early delayed whole-brain radiation-induced cerebral dysfunction. Rats were exposed to conventional fractionation (200 cGy/d, 5 d/wk; total dose, 4000 cGy). BBB changes were assessed by means of the quantitative 14C-alpha-aminoisobutyric acid technique and electron microscopy. Studies of the passage of horseradish peroxidase across the BBB permitted comparative quantitative isotopical and qualitative morphological data. Experiments were carried out 2 to 3 weeks after the completion of the radiation exposure. The transport of 14C-alpha-aminoisobutyric acid across the BBB increased significantly in cerebral cortex and cerebellar gray matter, averaging 1.3 to 1.5 times over the normal values. Electron microscopy disclosed an intense vesicular response of the cortical microvascular endothelium that occurred without the opening of the tight junctions and resulted in an intense transport of HRP across the intact endothelium. The present data indicate that moderate doses of whole-brain radiation induce well-defined changes in BBB function, which possibly are involved in the pathogenesis of radiation-induced cerebral dysfunction in humans.

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The definition of the methods for localizing the booster field used in the conservative treatment of early breast cancer is often blurred in several studies in the current literature. This paper is aimed at reporting a surgical-radiological method more objective than the clinico-anamnestic one used, so far, for planning the booster field. To this purpose 33 patients underwent conservative surgery in healthy tissue and radiopaque clips were inserted at the margins of the excision cavity. The booster field as defined with clinico-anamnestic standards was then simulated and later verified by a radiation therapy simulator. The clinical fields thus set up were correct in 15/33 cases. The authors discuss their results and compare them with literature data. The importance of the use of the surgical-radiological method to localize the booster field is stressed.

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We assessed, by means of the [14C]-2-deoxy-D-glucose autoradiography method, the effect of whole-brain x-radiation on local cerebral glucose utilization in the rat brain. Animals were exposed to conventional fractionation (200 +/- 4 cGy/day, 5 days/week; total dose, 4000 cGy). Metabolic experiments were made 2 to 3 weeks after completion of the radiation exposure. In comparison with control and sham-irradiated animals, cerebral metabolic activity was diffusely decreased after irradiation. Statistically significant decreases in metabolic activity were observed in 13 of 27 brain regions studied. In general, the brain areas with the highest basal metabolic rates showed the greatest percentage of decrease in glucose utilization. The concept that radiation suppresses glucose utilization before any morphological change takes place in the cell structures was the basis of this study. Metabolic alterations after irradiation may explain the syndrome of early delayed deterioration observed in humans after whole-brain radiotherapy. These studies have applications to observations made with the [18F]-fluorodeoxyglucose method in conjunction with positron emission tomographic scans in patients receiving radiation therapy for intracranial malignancies. The data reported here also have potential clinical implications for the evaluation of a risk/benefit ratio for radiotherapy in patients with benign neurosurgical diseases or children undergoing prophylactic treatment of the central nervous system.

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Whole brain irradiation (WBR) can produce acute and chronic neurological adverse effects, which are usually divided into acute, early delayed and late delayed reactions according to the time of onset. To assess the impact of WBR on brain functional parameters during the early-delayed phase, we employed the [14C]-2-deoxyglucose (2-DG) and the [14C]-alfa-aminoisobutyric (AIB) acid quantitative autoradiographic techniques to study local cerebral glucose utilization and blood-brain barrier permeability, respectively. Sprague-Dowley albino rats were exposed to conventional fractionation (200 Gy/day 5 days a week) for a total dose of 4000 Gy. Experiments were made 3 weeks after completion of the radiation exposure. In comparison with control and sham-irradiated animals, cerebral metabolic activity was diffusely decreased following irradiation. As a rule, brain areas with the highest basal metabolic rates showed the highest percentage drop in glucose utilization. Changes in blood-brain barrier function, as assessed by an increased transcapillary transport of AIB, were also demonstrated in specific brain regions. This study illustrates how moderate doses of WBR induce well-defined changes in brain metabolism and BBB function, which are possibly involved in the pathogenesis of the early-delayed radiation-induced cerebral dysfunction in humans.

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