High doses of olive leaf extract induce liver changes in mice.

Virtually ever since it was first commercialized in 1995, there have been several studies focusing on the use of olive leaf extract (OLE) as a natural therapy and its medical properties. The aim of this study was to investigate the effects of three different concentrations of OLE on the function of mice livers over the course of 14 weeks. Female ICR mice were divided into four groups, depending on OLE concentration used: 0%, 0.25%, 0.5%, and 0.75%. Alanine aminotransferase, alkaline phosphatase, total bilirubin and albumin serum concentrations were all measured. Histopathological changes of the liver were observed after haematoxylin and eosin, reticulin, and Masson's trichrome staining was carried out while liver mitochondrial bioenergetics were also evaluated. Alanine aminotransferase and alkaline phosphatase serum enzyme activities increased significantly in the groups in which 0.5% and 0.75% OLE concentrations were used. Histologically, all the groups exposed to OLE exhibited hyperplasia of the bile ducts, cholestasis, hepatocyte necrosis and inflammatory infiltrated. Hepatic fibrosis was observed in the groups featuring 0.5% and 0.75% OLE concentrations. The mitochondrial membrane potential, respiratory control ratio and ADP/O of samples from animals fed the higher OLE concentration was significantly decreased when compared to the control group.

DNA cytometry and kinetics of rat urothelial lesions during chemical carcinogenesis.

The aims of this study were to evaluate the DNA content of chemically-induced rat urothelial lesions and their relationship to the proliferation index and histological patterns. Sixty female Fisher 344 rats were divided randomly into six groups, four groups were exposed to N-butyl-N-(4-hydroxybutyl) nitrosamine for a period of 10 and 20 weeks, and two groups of ten rats were used as control animals. Paraffin sections were Feulgen stained and analyzed using DNA image cytometry analysis; histograms were classified as either diploid or aneuploid. Ki-67 immunoreactivity was determined by means of the streptavidin-biotin-complex immunoperoxidase method. All normal urothelium from the control groups were found to have diploid DNA content. The same histogram pattern was found in the simple hyperplasia group. As regards the other histological lesions, the frequency of the aneuploidy varied depending on the lesion type: 20% of aneuploidy were nodular hyperplasia, 32% of aneuploidy were dysplasias, 25% of aneuploidy were papilloma, 44% of aneuploidy were papillary neoplasm of low malignant potential, 22% of aneuploidy were low-grade papillary carcinoma, 100% of aneuploidy were high-grade papillary carcinoma and 100% of the aneuploidy were invasive carcinoma. Our results revealed the existence of a statistically significant relationship between DNA ploidy and histological pattern lesions (r=0.3, p<0.023). The Ki-67 proliferation index was significantly higher in aneuploid lesions than in diploid (r=0.56, p=0.01). There was also a statistically significant difference in the Ki-67 proliferation index in relation to the histopathological pattern (r=0.751, p<0.01). DNA content was associated with the Ki-67 proliferation index and histopathological grade. DNA content and prolife-ration index have critical roles to play during urothelial carcinogenesis.

Cell proliferation and DNA content in rat urothelial lesions after repeat intravesical instillations of mitomycin C and bacillus Calmette-Guérin.

AIM: To study cell proliferation and DNA content in urothelial lesions identified after repeated intravesical instillations of mitomycin C (MMC) and bacillus Calmette-Guérin (BCG) in normal rat urothelium. MATERIAL AND METHODS: A total of 45 rats were divided into nine equal groups: those intravesically instilled with MMC; those receiving BCG intravesically, and a control group intravesically instilled with a physiological solution of sodium chloride (SF). Animals were killed 1, 4 or 8 weeks after the last intravesical instillation. An immunohistochemical streptavidin-biotin-peroxidase technique was performed to investigate Ki-67 expression and the DNA ploidy status was measured using static cytometry. RESULTS: In urothelium exposed to MMC lesions such as simple hyperplasia, dysplasia, carcinoma in situ(CIS), and squamous cell metaplasia were identified. The proliferation index presented values of 11.73, 22.43 and 31.46% in hyperplasias, dysplasias, and CIS, respectively (p < 0.05). The frequency of abnormal DNA content amongst those animals exhibiting simple hyperplasias 25% were aneuploid, in the dysplasia 85.2% were aneuploid (p = 0.041). CIS were all multiploid, and squamous cell metaplasias were all diploid. Animals treated with BCG and SF presented no urothelial lesions and a diploid DNA content. CONCLUSIONS: The aneuploid and multiploid DNA content and proliferation index observed in urothelial lesions identified after repeated intravesical instillations of MMC reflect a high degree of genomic instability in such lesions which in itself may lead to rapid regeneration of new phenotypes.

Chemical carcinogenesis.

The use of chemical compounds benefits society in a number of ways. Pesticides, for instance, enable foodstuffs to be produced in sufficient quantities to satisfy the needs of millions of people, a condition that has led to an increase in levels of life expectancy. Yet, at times, these benefits are offset by certain disadvantages, notably the toxic side effects of the chemical compounds used. Exposure to these compounds can have varying effects, ranging from instant death to a gradual process of chemical carcinogenesis. There are three stages involved in chemical carcinogenesis. These are defined as initiation, promotion and progression. Each of these stages is characterised by morphological and biochemical modifications and result from genetic and/or epigenetic alterations. These genetic modifications include: mutations in genes that control cell proliferation, cell death and DNA repair--i.e. mutations in proto-oncogenes and tumour suppressing genes. The epigenetic factors, also considered as being non-genetic in character, can also contribute to carcinogenesis via epigenetic mechanisms which silence gene expression. The control of responses to carcinogenesis through the application of several chemical, biochemical and biological techniques facilitates the identification of those basic mechanisms involved in neoplasic development. Experimental assays with laboratory animals, epidemiological studies and quick tests enable the identification of carcinogenic compounds, the dissection of many aspects of carcinogenesis, and the establishment of effective strategies to prevent the cancer which results from exposure to chemicals.

Chemical carcinogenesis

The use of chemical compounds benefits society in a number of ways. Pesticides, for instance, enable foodstuffs to be produced in sufficient quantities to satisfy the needs of millions of people, a condition that has led to an increase in levels of life expectancy. Yet, at times, these benefits are offset by certain disadvantages, notably the toxic side effects of the chemical compounds used. Exposure to these compounds can have varying effects, ranging from instant death to a gradual process of chemical carcinogenesis. There are three stages involved in chemical carcinogenesis. These are defined as initiation, promotion and progression. Each of these stages is characterised by morphological and biochemical modifications and result from genetic and/or epigenetic alterations. These genetic modifications include: mutations in genes that control cell proliferation, cell death and DNA repair - i.e. mutations in proto-oncogenes and tumour suppressing genes. The epigenetic factors, also considered as being non-genetic in character, can also contribute to carcinogenesis via epigenetic mechanisms which silence gene expression. The control of responses to carcinogenesis through the application of several chemical, biochemical and biological techniques facilitates the identification of those basic mechanisms involved in neoplasic development. Experimental assays with laboratory animals, epidemiological studies and quick tests enable the identification of carcinogenic compounds, the dissection of many aspects of carcinogenesis, and the establishment of effective strategies to prevent the cancer which results from exposure to chemicals.

A sociedade obtém numerosos benefícios da utilização de compostos químicos. A aplicação dos pesticidas, por exemplo, permitiu obter alimento em quantidade suficiente para satisfazer as necessidades alimentares de milhões de pessoas, condição relacionada com o aumento da esperança de vida. Os benefícios estão, por vezes associados a desvantagens, os efeitos resultantes da exposição a compostos químicos enquadram-se entre a morte imediata e um longo processo de carcinogênese química. A carcinogênese química inclui três etapas definidas como iniciação, promoção e progressão. Cada uma delas caracteriza-se por transformações morfológicas e bioquímicas, e resulta de alterações genéticas e/ou epigenéticas. No grupo das alterações genéticas incluem-se mutações nos genes que controlam a proliferação celular, a morte celular e a reparação do DNA - i.e. mutações nos proto-oncogenes e genes supressores de tumor. Os fatores epigenéticos, também considerados como caracteres não genéticos, podem contribuir para a carcinogênese por mecanismos de silenciamento gênico. A utilização de diferentes metodologias possibilita o reconhecimento e a compreensão dos mecanismos básicos envolvidos no desenvolvimento do cancro. Ensaios experimentais comanimais de laboratório, estudos epidemiológicos e alguns testes rápidos permitem identificar compostos carcinogênicos, analisar os eventos envolvidos na carcinogênese e estabelecer estratégias para prevenir a exposição a estes agentes.

A phyllodes tumor of the urinary bladder in a rat.

AIM: The aim of this short communication was to describe a case of phyllodes tumor of the urinary bladder discovered in a female Fisher 344 rat that died during an experimental protocol to induce and study urothelial lesions by N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN). METHODOLOGY: From a group of several female rats exposed to BBN via drinking water over the course of 20 weeks, one animal died. At necropsy, a solid mass was identified in the urinary bladder lumen, with a diameter of 0.8 x 0.7 cm. This tumor was processed for histopathological examination and Feulgen coloration. RESULTS: Microscopically, the mass in the bladder was observed to be a phyllodes tumor. DNA content measured by image analysis of a Feulgen-stained section of the tumor and stroma cells displayed diploid DNA content in both components of the tumor. CONCLUSION: This is the first reported phyllodes tumor in a rat's urinary bladder. The exact prognosis and histogenesis of phyllodes tumors of the urinary bladder remains to be determined by the accumulation of data from additional cases.

DNA study of bladder papillary tumours chemically induced by N-butyl-N-(4-hydroxybutyl) nitrosamine in Fisher rats.

To examine DNA abnormalities in bladder papillary tumours induced by N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN) in female rats, using image cytometric DNA analysis and cytogenetics. Thirty female rats were exposed to BBN in their drinking water for 20 weeks. One group of 10 animals served as controls. The animals exposed to BBN were killed at a rate of two per week, with the bladder being collected under aseptic conditions and those tumours with exophytic growth removed. The nuclear DNA content of the tumours was evaluated using image cytometric analysis. In two rats part of the tumour pieces was stipulated for culturing. Cytogenetic analysis was performed on at least 30 cells from each cell population and on both tumours. Papillary carcinomas were classified as low grade and high grade. DNA ploidy studies were carried out on 28 low-grade and 21 high-grade papillary carcinomas. Histograms obtained by image analysis showed that a normal urothelium was diploid; 28.6% and 100% of low-and high-grade papillary carcinomas were aneuploid respectively. Both tumours used for cell culture showed multiple numerical and structural chromosome alterations and several marker chromosomes. Image cytometric DNA analysis proved to be a good and reliable method for examining DNA alterations in papillary bladder carcinomas. The present findings establish that the DNA content is statistically different between low-grade and high-grade papillary carcinomas and that deviation from the diploid number is markedly higher in the high-grade ones. In addition, the occurrence of marker chromosomes seems to be related to the aggressiveness of the tumour.

[Probesci strategy: a cheaper therapeutic approach for obese patients]. / Estrategia probesci: un abordaje terapéutico de menor coste para el paciente obeso.

Obesity has become epidemic in Western countries. From clinical practice, obestity may be considered as a disease characterized by an excess of body fat mass, but patients usually demonstrate different responses to the same therapeutic strategy. It could be possible that the latter may be a consecuence of different pathophysiological factors among obese patients. Therefore, a detailed and thorough phenotyping of patients may enable clinitians to establish groups of patients that may respond in a homogeneous and effective way to a specific treatment for obesity. However, this type of approach can be especially time-consuming and may increase costs. In this study we describe the "PROBESCI" strategy, which is a novel system of studying the obese patient at the first visit, performed in groups of patients, aimed to the collection and analysis of data in order to categorize phenotypic profiles which may achive homogeneous responses to a specific therapy. We also analyze the costs of this new strategy compared to those of an individual consultation, showing a decrease of 58% for the first visit, and of 21% of the total costs throughout treatment.

Experimental bladder carcinogenesis-rodent models.

Several rodent models of bladder cancer development have been established. The aim of this review article is to provide a critical assessment of different animal models available for the study of bladder carcinogenesis, its chemoprevention and therapy. All, except for transgenic and knockout animals, require 8-12 months experimental periods in order to generate a high yield of neoplasias. Spontaneous bladder tumor models are extremely rare. The significance of the results from animal experiments is dependent upon the selection of a suitable animal model. There are no rules regarding the choice of a model, it is however very useful to have knowledge of relevant comparative medical aspects concerning this subject. We describe chemical carcinogens most commonly used to induce bladder cancer, pellet implantation and urinary calculi, agents that promote bladder cancer, and irradiation. We also evaluated other tools such as cell cultures, tumor implantation and transgenic models for bladder cancer, that have been developed to study the process. The review considers how several imaging techniques can be applied to study rodent bladder carcinogenesis.

Meningitis fulminante por Neisseria meningitidis serotipo W-135 y déficit de complemento / Fulminant Meningitis caused by N. Meningitidis serotype W-135 and complement deficiency

La Neisseria meningitidis serogrupo W-135 está implicada en casos aislados de meningitis aguda en nuestro país. Se describe el caso de una paciente de origen estadounidense, que ingresa por un cuadro compatible con meningitis aguda, aislándose en el cultivo de LCR N. meningitidis del serotipo W-135, comprobándose posteriormente la existencia de un déficit de la fracción C1q del complemento

The Neisseria meningitidis serogroup W-135 has been involved in isolated cases of acute meningitis here in Spain. There is described the case of one American-born patient who is admitted with clinical manifestations of acute meningitis, and with N. meningitidis serotype W-135 being isolated in cerebrospinal fluid (CSF) culture. Complement fraction C1q deficiency is later verified

Effects of clopidogrel and ticlopidine on experimental diabetic ischemic retinopathy in rats.

Ticlopidine, a thienopyridine that prevents the progression of diabetic retinopathy in humans, was recently shown to increase nitric oxide (NO) production in human neutrophils. The thienopyridine clopidogrel has been found to be clinically useful in the secondary prevention of thrombotic events. The aim of the present study was to evaluate the effect of clopidogrel on ischemic retinopathy in streptozotocin-diabetic rats and its influence on prostanoids and NO production. We compared nondiabetic rats and rats after 3 months of diabetes that were given three doses (1, 10 or 20 mg/kg per day p.o.) of ticlopidine or clopidogrel from the first day of diabetes. The variables recorded after 3 months of diabetes were platelet aggregation, thromboxane B(2) (TxB(2)) production, 6-keto-prostaglandin F(1)(alpha) (stable metabolite of prostacyclin), aortic NO, plasma nitrites/nitrates, and the percentage of the retinal surface occupied by horseradish peroxidase (HRP)-permeable vessels. In diabetic rats, platelet aggregation and thromboxane concentration were increased, and prostacyclin, NO and area occupied by HRP-permeable vessels were decreased. Ticlopidine and clopidogrel reduced the maximum extent of platelet aggregation in a dose-dependent manner: maximal inhibition with respect to untreated diabetic rats was 48.6% with ticlopidine and 66.6% with clopidogrel. Ticlopidine reduced thromboxane B(2) only at a dose of 20 mg/kg per day p.o. (47.4% inhibition) and clopidogrel at doses of 10 mg/kg per day (51% inhibition) or 20 mg/kg per day (51.7% inhibition). Aortic prostacyclin production did not change after treatment with either thienopyridine. Treatment with ticlopidine reduced the inhibition of NO production in untreated rats (89.6% inhibition) to 0.9%, and clopidogrel reduced inhibition to 30%. Treatment with ticlopidine or clopidogrel reduced the retinal nonperfused area from 86.8% inhibition in untreated rats to 45.6% and 25.3%, respectively. In conclusion, the early administration of thienopyridines in streptozotocin-diabetic rats partly prevented the appearance of diabetic retinal ischemia.

Effect of aspirin on prostanoids and nitric oxide production in streptozotocin-diabetic rats with ischemic retinopathy.

The importance in experimental diabetic retinopathy of prostacyclin and nitric oxide (NO), as well as the possible effect of acetylsalicylic acid (ASA), are well known. To investigate the effect of two doses of aspirin in the prevention of retinal ischemia in streptozotocin-diabetic rats, we compared nondiabetic rats and diabetic rats after 1, 2 and 3 months of diabetes, and diabetic rats treated with 2 mg or 10 mg ASA/kg per day p.o. from the first day of diabetes. The parameters determined after 1, 2 and 3 months of development were platelet aggregation, thromboxane B(2) (TxB(2)) production, 6-keto-prostaglandin F(1)(alpha) (stable metabolite of prostacyclin), NO, plasma nitrites/nitrates, and percentage retinal surface occupied by horseradish peroxidase (HRP)-permeable vessels. In diabetic rats platelet aggregation and thromboxane concentration were increased, and prostacyclin, NO and area occupied by HRP-permeable vessels were decreased. Acetylsalicylic acid reduced platelet aggregation, and lowered thromboxane production by 82%-99%. Prostacyclin production was inhibited by 92%-95% with 10 mg ASA/kg per day, and by 8%-20% with 2 mg ASA/kg per day. In diabetic rats NO production increased after 2 and 3 months of treatment to levels seen in nondiabetic rats. The reduction in HRP-permeable retinal surface decreased from a maximum of 87% in DR to 51% after treatment with 2 mg ASA/kg per day, and to 62% after 10 mg ASA/kg per day. We conclude that ASA (2 mg/kg per day and 10 mg/kg per day) increased NO production in streptozotocin-diabetic rats and reduced the degree of retinal ischemia.

C(60)-based triads with improved electron-acceptor properties: pyrazolylpyrazolino[60]fullerenes.

A series of triad pyrazolylpyrazolino[60]fullerenes has been prepared in one pot from suitably functionalized hydrazones by 1,3-dipolar cycloaddition reactions under microwave irradiation. The electrochemical properties of the compounds obtained were investigated by cyclic voltammmetry, and they show better electron acceptor character than the parent C(60) in all cases. Fluorescence experiments and time-resolved transition spectroscopy indicate the existence of photoinduced charge-transfer processes with the C(60) triplet acting as the acceptor.

[Usefulness of the quantification of (99M)Tc-MIBI uptake in breast neoplasms in the preoperative assessment of tumor aggressiveness]. / Utilidad de la cuantificación de la captación de (99m)Tc-MIBI en neoplasias mamarias en la valoración preoperatoria de la agresividad tumoral.

UNLABELLED: (99m)Tc-MIBI has been proposed as an imaging diagnostic method in a large variety of human malignant tumors. At present, the mechanism by which (99m)Tc-MIBI is uptaken and concentrated by the malignant cells is not totally known. Some mammary neoplasms do not show any uptake of (99m)Tc-MIBI. This study aims to determine if there is any correlation between the uptake of (99m)Tc-MIBI by the tumor and the different histopathological parameters involved in tumoral aggressiveness. To do so, we have studied 100 patients with breast cancer. All of them underwent a breast scintimammography with (99m)Tc-MIBI with semiquantitative analysis by means of a tumor-to-background ratio calculated in every projection. After surgery, an experienced pathologist determined tumor size, axillary lymph node metastases, histological grade (Scarff Bloom Richardson) (SCBR), nuclear grade, mitotic index, presence of cellular atypia and estrogen and progesterone receptor expression. RESULTS: A statistically significant correlation (p < 0.005) has been found between tumor-to-background (T/B) ratios of (99m)Tc-MIBI uptake and tumor SCBR histological grade. A correlation between (99m)Tc-MIBI uptake and the mitotic index, cellular atypia and nuclear grade has also been found. No correlation was found in our study with tumor size, hormone receptor expression or axillary lymph node metastases. CONCLUSIONS: (99m)Tc-MIBI uptake in breast cancer is correlated with the tumoral differentiation grade: the smaller the tumoral cellular differentiation (greater aggressiveness), the greater the uptake. On the other hand, no correlation was found between the uptake of (99m)Tc-MIBI and the classical pathological parameters that define tumoral aggressiveness, such as size and axillary lymph node metastasis.

[99m Tc-MIBI scintigraphy compared to mammography in the diagnosis of breast cancer in dense, operated and young women breasts]. / Gammagrafía con 99mTc-MIBI frente a la mamografía en el diagnóstico de cáncer de mama en mamas densas, mamas intervenidas y mujeres jóvenes.

UNLABELLED: Breast scintimammography with 99mTc-MIBI has proven to be a useful complement to mammography in the diagnosis of breast cancer in the female population. Although the mammography, along with a physical examination, is the backbone of breast cancer diagnosis, there are groups of patients in whom the mammography has an even lower specificity. OBJECTIVE: Our study has aimed to assess the usefulness of breast 99mTc-MIBI scintimammography in those situations in which the mammography was indeterminate, such as, in dense breasts, young females or breasts with architectural distortion after surgery or radiation therapy. MATERIALS AND METHODS: We studied 109 females with mammographically dense breasts, 8 young females under 30 and 24 patients who had undergone previous surgery or radiation therapy. All cases were studied to rule out breast cancer. Final diagnosis was established with excisional biopsy. RESULTS: In dense breasts MIBI scintimammography sensitivity was 88% and the mammography one 81%. MIBI scintimammography specificity was 90% and the mammography 28%. In young females MIBI scintimammography sensitivity was 100% and the mammography 50%, MIBI scintimammography specificity 100% and the mammography 20%. In previous surgery, MIBI scintimammography sensitivity was 80% and the mammography 80%, MIBI scintimammography specificity 100% and the mammography 42%. CONCLUSION: Breast scintimammography with 99mTc-MIBI is an excellent diagnostic technique with high specificity. Undoubtedly it is complementary to mammography in those cases where mammography has major limitations such as dense breasts, young females and breasts with severe scarring after surgery or radiation therapy.

Modification of regioselectivity in cycloadditions to C70 under microwave irradiation

The regioselectivity of the cycloaddition of N-methylazomethine ylide to C70 can be modified by using microwave irradiation as the source of energy. Under microwave irradiation and by choosing the appropriate solvent and irradiation power, the 5-6 isomer is the major product, a situation that is in contrast to conventional heating where the 1-2 isomer predominates. Moreover, isomer 7-21, which represents 13% of monoadducts under classical heating, is not formed under microwave irradiation and with ODCB as solvent. Theoretical calculations predict an asynchronous mechanism and suggest that the modification of the regiochemical outcome is related to the relative energies and hardnesses of the transition structures involved.

Synthesis and properties of isoxazolo[60]fullerene-donor dyads.

A series of isoxazolo[60]fullerenes has been prepared in one pot from aldoximes under microwave irradiation. Several donors and acceptors were used as substituents. The absorption and emission spectra of these compounds in polar solvents suggest a weak charge-transfer interaction between the oxygen atom of the isoxazoline moiety and the C(60) cage, as well as a stronger interaction between the donor and the fullerene cage when the attached groups are p-N,N-dimethylaniline or ferrocene. The electrochemical properties of the compounds were investigated and they show the same or better acceptor character than C(60) in all cases. Theoretical calculations support the results obtained. Solvent effects in the (1)H NMR spectra have been determined and provide useful information concerning the polarization of dyads.

Changes in cannabinoid receptor binding and mRNA levels in several brain regions of aged rats.

We have recently found that cannabinoid receptor binding and gene expression markedly decreased in extrapyramidal structures of aged rats. The present study was designed to analyze the possible existence of similar aging-induced changes in cannabinoid receptor binding and gene expression in brain regions other than extrapyramidal areas, but that also contain a significant population of cannabinoid receptors, such as the cerebellum, hippocampal structures, limbic and hypothalamic nuclei, the cerebral cortex and others. To this end, we analyzed cannabinoid receptor binding, using autoradiography, and cannabinoid receptor mRNA levels, using in situ hybridization, in slide-mounted brain sections obtained from young (3 month old) and aged (> 2 year old) rats. Results were as follows. In the cerebellum, aged rats exhibited a marked decrease in cannabinoid receptor binding in the molecular layer (-33.3%), although accompanied by no changes in mRNA levels in the granular layer. In the cerebral cortex, a small, although statistically significant, decrease in binding was found in the deep layer (VI) (-18.3%) of aged rats, whereas no changes were found in the superficial layer (I). As in the case of the cerebellum, mRNA levels did not change in the cerebral cortex layers (II-III and V-VI). The different regions of the Ammon's horn of the hippocampus exhibited similar cannabinoid receptor binding levels in aged and young rats. Interestingly, mRNA levels decreased in aged rats to a small, but statistically significant, extent (CA1: -26.1%; CA2: -21.6%; CA3: -14.4%). This was also seen in another hippocampal structure, the dentate gyrus (-14.6%), although in this region binding levels increased in aged rats (+28.4%). Two hypothalamic structures, the arcuate nucleus and the ventromedial hypothalamic nucleus, exhibited decreased cannabinoid receptor binding in aged rats (-31.1% and -30.3%, respectively), but this was not seen in the medial preoptic area. This was accompanied by no changes in mRNA levels in the ventromedial hypothalamic nucleus. In the limbic structures, aged rats exhibited similar binding levels to young rats. This was seen in the nucleus accumbens, septum nuclei and basolateral amygdaloid nucleus. However, mRNA levels slightly decreased in the basolateral amygdaloid nucleus (-13.4%), whereas they were not altered in the septum nuclei. Finally, other brain structures, such as the central gray substance and the brainstem, exhibited similar binding levels in aged and young rats. However, it is important to note that mRNA levels increased significantly (+211.2%) in the brainstem of aged rats, an area where the levels of binding and mRNA were very low in young rats. This marked increase may be related to an increase in the presence of glial elements in this region, as revealed by the increase in the immunoreactivity for glial fibrillary acidic protein observed in the brainstem of aged rats as compared to young animals. In summary, senescence was associated with changes in cannabinoid receptors in the cerebellum, the cerebral cortex, limbic and hypothalamic structures, the hippocampus and other brain regions. However, the changes observed (i) were not as marked and relevant as those early reported in extrapyramidal areas, and (ii) exhibited regional differences that might be attributed to the different roles played by these receptors in each region. Of particular relevance by their magnitude were the aging-induced decrease in binding found in the cerebellum and the hypothalamus, and the increase in mRNA levels observed in the brainstem. The latter might be related to an increase in the presence of glial cells which might contain cannabinoid receptor mRNA.

A phase I and pharmacokinetic trial of terephthalamidine (NSC 57155) as a 120-hour continuous infusion.

In this phase I study, terephthalamidine was administered as a 120-hour continuous infusion repeated every 21 days. Thirteen patients received 27 courses of terephthalamidine at four dose levels ( 14, 28, 46, and 70 mg/m2/day). Dose-limiting toxicity consisted of profound and intractable anorexia, weight loss and prostration in all patients. Toxicity was delayed and accompanied by hyponatremia and hypokalemia. No hematologic or other toxicity was documented. One patient with adenocarcinoma of the lung had a 40% decrease in mediastinal lymph nodes and resolution of a pleural effusion lasting 2 months. Pharmacokinetic analysis by HPLC was performed in all patients during their first course. The harmonic mean terminal half-life for terephthalamidine was 23 hours with a plasma clearance of 1.7 1/hr/m2. Both plasma concentrations achieved during infusion (r2 = 0.9) and area under the curve (AUC) (r2 = 0.8) were proportional to increase in dose (p < 0.002). Renal excretion accounted for 64% of the total cumulative dose, with an average renal clearance of 1.16 1/hr/m2. Due to the unacceptable toxicity seen at all doses with this schedule, no further studies are recommended unless the mechanism of toxicity is better understood and can be prevented.