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There is a growing body of evidence that plant polyphenols such as resveratrol, anthocyanins, catechins, and terpenes like taxol are effectively used in the treatment of chronic conditions including cancer, Alzheimer, Parkinsonism, diabetes, aging, etc. The link between oxidative stress and inflammation is well accepted. Thus, the mechanism of action of these natural products is partly believed to be through their significant antioxidant properties. The main constituent of green tea, with clinical significance, is epigallocatechin gallate (EGCG). It has been associated with antitumor, anti-Alzheimer, and anti-aging properties, improve redox status at the tissue level possibly preventing system level structural damage. This review focuses on EGCG and its potential therapeutic role in health and disease.

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Hepatic fibrosis constitutes a serious insult to the liver, with a substantial negative impact on the quality of life of such patients worldwide. It is a consequence of severe liver damage and occurs as the result of several factors. Chronic alcoholism is the most common cause. Fibrosis also results from chronic viral hepatitis and autoimmune hepatitis. Prolonged exposure to environmental toxins such as carbon tetrachloride (CCl(4)) can also lead to fibrosis. In the present study, the hepato-protective effects of green tea extract (GTE) on hepatic fibrosis in a rat liver CCl(4)-induced fibrosis model were examined histologically, 3-dimensionally and biochemically. GTE was prepared from dried green tea leaves and lyophilized. Male albino rats (n=20) weighing 200-250 g were divided into four groups: GI, control; GII, administered 50 mg/kg GTE dissolved in physiological saline daily for four weeks; GIII, administered 40% CCl(4) (1 ml/kg body weight) by subcutaneous injection daily for four weeks; and GIV, treated as GIII, followed by 50 mg/kg GTE dissolved in physiological saline daily for 4 weeks. Histology and 3-dimensional scanning electron microscopy showed hepatic fibrosis with intermingled fibers located between cells in the liver tissues of the CCl(4)-treated rats. Fibrotic lesions virtually disappeared after four weeks of treatment with GTE, returning the architecture of liver tissue back to its normal state. Also, the levels of the hepatic enzymes alanine aminotranferase and aspartate aminotransferase returned to their normal levels after treatment with GTE. The rats were found to regain their normal body weight and their fur color, which had faded due to weight loss. The autopsy results showed the animal liver returning to normal shape and color. Thus, green tea extract is a potent treatment for hepatic fibrosis caused by CCl(4) in this animal model.

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A comparison of crude curcuminoid extract and purified curcumin was made to evaluate hepato- and immunoprotective effect of Curcuma longa (turmeric) Zingiberaceae. Carbon tetrachloride (CCl4) induced cellular hepatic damage was evaluated by transmission electron microscopy, hepatic enzymes and thiobarbituric acid reactive species (TBAR) values. A selective cytolytic effect of CCl4 was observed among immature (PNA+) thymocytes and peripheral helper (CD4+) T lymphocytes in spleen and was paralleled by a significant reduction in CD25, CD71 and Con A receptor expression. Treatment with curcuminoid crude extract at two different doses, showed a significant cellular recovery among hepatocytes, which was reflected in a reduction of hepatic enzymes and TBAR values. A significant restoration of lymphocyte viability and CD25, CD71 and Con A receptor expression in both immature (PNA+) thymocytes and splenic helper (CD4+) T lymphocytes was observed. Turmeric crude extract, at both low and high dose, was found to be more efficient as compared to purified curcumin.

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OBJECTIVES: We investigated survey responses to the Smoke-free Bars Law by residents of Long Beach, California (population 460,000), a city that reflects the state's diverse population. The research specifically aimed to determine: (1) residents' approval for the 1998 California Smoke-free Bars Law when it was implemented; and (2) changes in approval between baseline and 2-year follow-up. Data were also assessed for the demographic characteristics of the respondents and whether the respondents were self-acknowledged smokers or non-smokers. STUDY DESIGN: A random telephone survey was conducted in 1998 and 2000 in Long Beach to determine the degree of community support for the 1998 state law that prohibited smoking in all workplaces including alcohol-serving establishments. The numbers analysed were 784 in 1998 and 1237 in 2000. METHODS: Statistical analyses used in this research included univariate frequency distributions and logistic regression for 1998 and 2000. RESULTS: The major findings were as follows. Overall community approval for the 1998 state law increased from 65.2% in 1998 to 72.6% in 2000. Over this period, the rate of approval by smokers increased from 20.6% to 37.1%, and the rate of approval by non-smokers increased from 74.5% to 80.3%. CONCLUSIONS: The general public in a large city in California strongly approve of the prohibition of smoking in all indoor public places. This strong endorsement has major public health implications.

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OBJECTIVES: In the present research, we assessed the relationship between characteristics of the residents of Long Beach, California, a typical city in America, and their opinions regarding the uses of master settlement agreement (MSA) funds. METHODS: The statistical analyses used in the present research included univariate frequency distributions, cross-tabulations, and classification and regression trees. RESULTS: The results indicate that the majority of Long Beach residents share the opinion that the MSA funds should be allocated to health programmes. They do not, however, feel that these funds need to be earmarked solely for smoking prevention or cessation. CONCLUSIONS: Due to state budget deficits, legislators may strongly advocate for the MSA funds to be used for non-health purposes. Our findings provide support for community advocates who wish to bring the current uses of MSA funds and tobacco taxes to the forefront of national and international public debate.

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The anti-oxidant food additive, butylated hydroxytoluene (BHT), was fed to Sprague-Dawley rats at three concentrations: 0.2%, 0.4% and 0.8% for periods of 6, 12, 18 and 24 weeks, and the results were compared with corresponding groups treated with a potent carcinogen, 7,12-dimethylbenz[a]anthracene (DMBA) groups, with olive oil, and with untreated control groups. BHT resulted in a significant increase in liver weight. The liver cells presented gradual vacuolization, cytoplasmic disintegration, "moth-eaten" appearance, ballooning degeneration, hepatocellular necrosis, aggregation of chromatin material around the periphery of the nuclear envelope, SER proliferation, RER clumping with broken cisternae, withered and autolyzed mitochondria, augmentation of lipid droplets and glycogen depletion. On the other hand, there was no sign of tumorigenicity. Whether or not BHT acts as a carcinogen in long-term administration may depend not only upon the organ system examined, but also on the strain of the animal used.

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In the present study, the cytotoxic effects of Kuwaiti weathered crude oil and a potent carcinogen (DMBA) on rat liver cells were examined by light and electron microscopy at each of 4 sampling periods after the start of low dosing (0.5 and 0.2 mg/kg) of feed. Such effects were compared with those of olive oil and uncontaminated food-exposed controls. The results confirm a pronounced cell damage which statistically not significant (p < 0.05). In crude oil, the organelle changes were variable and highly comparable to that of DMBA. The nuclei were mostly disintegrated while the cell showed demarcation of cytoplasmic vacuolization, lipid augmentation, and mitochondrial aberrations. The latter showed a remarkable association with the rough endoplasmic reticulum and lipid droplets, and appeared as decayed and diffused structures within the cell matrix. There was no comparable changes in the hepatocytes of animals fed with uncontaminated food except for the formation of lipid droplets in the olive oil-fed groups. Although the animals food was contaminated with Kuwaiti weathered oil formed in 1991 were exposed to extreme seasonal temperatures, yet the residues of such oil led to severe histopathological alterations in the liver cells which were similar to those of DMBA-treated cells. There is the need to pay attention to potential hazardous effects of the crude oil on environments.

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This study shows the development of two major deformities in the non-stenosed kidney of the 2K-1C Goldblatt model; namely the widening of the LIS and the enlargement of the basilar interdigitations of the proximal tubule cells. These deformities were much less in the 2K-1C animals treated with the angiotensin I converting enzyme inhibitor (AICEI) cilazapril. From these findings it is suggested that the non-stenosed kidney is operating under the diuretic effect of the elevated systemic blood pressure (SBP) via an increase in the renal interstitial hydrostatic pressure (RIHP). Therefore, the AII antidiuretic effect is masked by the diuretic effect of the elevated SBP. The suggested rise in urine output fits well with the idea that kidneys lose water and sodium when SBP increases enormously. Therefore, in this model of hypertension, the non-stenosed kidney tries to lower SBP by losing water and sodium, an excretion behavior which is opposite to that of the stenosed kidney. Thus, the rise in SBP in this model is probably due to an increase in the vascular peripheral resistance rather than fluid accumulation.

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Phosphatase cytochemical activity in the normal glomerulus of the desert gerbil Meriones crassus was demonstrated using cerium ions as capturing agents. Three major enzymes have been recognized: sodium-potassium adenosine triphosphatase (Na(+)-K(+)-ATPase), alkaline phosphatase (ALPase) and acid phosphatase (ACPase). However, cytochemical staining for these markers to map their localizations and distributions reveal a high positivity of Na(+)-K(+)-ATPase. This appeared as uniform dense precipitates surrounding the glomerular basement membrane (GBM) and the plasma membranes of the epithelial and endothelial cells of the glomerular layers. Negligible ALKase reaction product being over the glomerular epithelia including the GBM. In contrast, the cytochemical profiles of ACPase was unusual, with dense reaction products extensively covering the endoplasmic reticulum at the region of Golgi apparatus products lysosomes (GERL) complex, including its cisternal and tubular elements and the lysosomal-vacuolar apparatus of the glomerular epithelial cells. All other subcellular organelles showed no activity. For Na(+)-K(+)-ATPase, the reaction product was successive when acetate buffer (as decalcifying agent, pH 5.0) was used. This reaction was still seen when a medium containing levamisole was used. Cytochemical controls for all enzymes were incubated in substrate-free media including those using levamisole as an inhibitor of ALPase. The data presented, which is reported for the first time, is not an attempt to determine the contribution of the selected phosphatases in the glomerular physiology and pathology. Such findings may, nevertheless, have functional implications in the fact that these markers may be involved in the ultrafiltration and other metabolic activities of the glomerulus at the molecular and/or cellular level. In addition to earlier morphological and recent histochemical work, the present study updates and recognizes information to be used as a baseline to which the gerbil model can now be employed to investigate the behavioural adaptations of the desert rodents.

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The present work describes the cytochemical localization of Na(+)-K(+)-ATPase in the proximal convoluted tubule cells of the gerbil Meriones crassus. By using CeCl3 as capture agent, a fine, uniform reaction product was distributed mainly across the basolateral membranes and at the apical surface. This study provides evidence that the ATPase enzyme studied is actually Na(+)-K(+)-ATPase because acetate buffer (bleaching agent) had no decalcifying effect, nor did the subsequent application of levamisole, an inhibitor of alkaline phosphatase, which can hydrolize ATP. Such findings may serve to provide insights into the regulatory role of the Na(+)-K(+)-ATPase in intra-extra cellular balance in the basolateral membranes of the proximal convoluted tubule cells of this desert animal which show thick basal laminae with their membrane-bound bodies. However, there is a lack of knowledge regarding the transport function of the assayed enzyme and these bodies.

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Histochemical activity of alkaline phosphatase in the proximal convoluted tubule of the gerbil Meriones crassus has been detected. The reaction product was strongly marked at both the apical surface and the basal part of the cells comprising the basal infoldings with their extended tips and the profiles of the membrane-bound bodies that were easily recognisable by their rounded shape. The reaction product was in the form of fine, uniform deposits in response to cerium chloride as a capture agent. Other cytoplasmic structures did not display these deposits. In addition, the study provided the application of levamisole which caused remarkable reduction of the enzyme activity. Using lead nitrate as a capture agent, the sections showed dense coarse, irregular clusters nearly at the same sites. Control experiments, processed in the absence of the substrate sodium beta-glycerophosphate did not demonstrate the presence of any deposits. The present study, which demonstrates for the first time the presence of alkaline phosphatase activity in the proximal convoluted tubule cells of such desert rodents, does not consider the relationship of the enzyme localization and the basal components of the cells including the nature of the membrane-bound bodies which are still under investigation.

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The aims of the present study were to characterize by electron microscopy the morphological features of the erythrocytes of normal adult and young camels Camelus dromedarius in a renal blood vessel and in a smear. These cells are thin and elliptical, with a slight central elevation. They are slightly larger, but thinner than those reported by other authors. It is found that the renal blood vessels in adults have a thicker basal lamina with the presence of electron dense membranous bodies. These two features were described in different parts of the uriniferous tubules of the camel in previous studies. The numerical data of the haematochemical parameters that are reported here are in general similar for both adult and young camels, while they differ from those of other studies, this may have resulted from their unknown provenance and their previous dietary regime. Moreover, these parameters probably relate to the arid environment of the animal.

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The ultrastructural findings on the kidney cells of the gerbil Meriones crassus have shown the presence of finger-like projections emerging from the basal part of the epithelial cells of the proximal convoluted tubules into the matrix of the thick basal laminae and that structure like membrane-bound bodies are commonly seen in continuity with these processes. Such findings would give clues for the possible biogenesis of the membrane-bound bodies from the epithelial cells. Such an origin is consistent with the idea that either all or part of the population of membrane-bound bodies is produced by a process of budding off from the basal cell membrane rather than by extension of an intracytoplasmic precursor through the plasma membrane.

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The renal haemopoietic tissue of the mudskipper Periophthalmus koelreuteri was examined by light and electron microscopy. Leukopoietic zone surrounding melanomacrophage center and erythropoietic zone were differentiated. The ultrastructural features of the cellular components of the haemopoietic compartments are similar to those described in other fishes. Despite the presence of lymphoid cells, this tissue is mainly myeloid, and active granulopoiesis and erythropoiesis occur, as in the red bone marrow of higher vertebrates. © 1992 Wiley-Liss, Inc.

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Kidney samples of the camel Camelus dromedarius were aldehyde fixed and glycerol impregnated for ultrathin-section and freeze-fracture studies of the basal lamina. Results obtained show the presence of extracellular membrane-bound bodies within the thick basal lamina of the tubular portion of the nephron. The 10- to 500-nm bodies appear isolated and are found at various levels along the width of a highly structural lattice basal lamina. The bodies are observed either in small groups or as single structures which are invariably surrounded by a clear halo of the basal lamina. In ultrathin sections they appear limited by a typical unit-membrane structure, and their interior may appear empty or may exhibit material of variable electron opacity. Freeze-fracture replicas reveal the limiting membrane of the bodies which appear either as concave or convex structures. Intramembrane particles (IMPs) measuring between 5 and 15 nm are present in some of the bodies, whilst others appear devoid of IMPs. The IMPs are present in both concave and convex surfaces and are usually aggregated into clumps. The region of the basal lamina which contains the membrane-bound bodies is usually granular except in the area immediately surrounding the bodies which corresponds to the clear halo observed in thin sections. Although these basal lamina membrane-bound bodies appear to be similar to matrix vesicles previously described in mineralizing tissues, it seems unlikely that they are involved in calcification. It is possible that the membrane-bound bodies and the highly configurated basal lamina may be related to ionic transport mechanisms which are associated with the high osmolarity of the camel urine.

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Kidney samples of the adult gerbil Meriones crassus were aldehyde fixed and Epon embedded for studies of the general features of various parts of the nephrons, with particular attention to their basal laminae in all regions. Results obtained showed the presence of thick basal laminae (2-6 microns) in the parietal layer of Bowman's capsule, proximal convoluted tubule, thin loop of Henle and distal convoluted tubule. With the aid of the electron microscope, extracellular vesicular bodies were observed within the thick basal laminae in the previous regions. The bodies (50-500 nm in diameter) were found at various levels of the basal laminae. Some of them appeared to have been pinched off directly from the epithelial layer and to have moved to the underlying basal lamina, which may suggest that these vesicular bodies originated from the epithelial layer. The bodies, with a variable electron opacity, may be found either in small groups or as a single structure surrounded by a clear halo of basal lamina.

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The nephron of the one-humped camel Camelus dromedarius was investigated by light and transmission electron microscopy. Besides the many features common to other mammalian kidneys, the nephron of the camel is unique in having an unusually thick basal lamina underlying the epithelial cells of the nephron, the thickest being found in part of the parietal layer of Bowman's capsule and the thin limb of the loop of Henle. In the latter, the membrane usually appears lamellated and contains numerous tiny vesicles. In other parts of the nephron, the basal lamina usually has a homogenous appearance. The possible significance of the thickening of the basal lamina is discussed in relation to the general high renal efficiency of the camel.

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Wandering cells that infiltrate between the principal cells of the nephron of the mudskipper Periophthalmus koelreuteri were examined by transmission electron microscope. These cells were found at various levels between the tubule cells and were more abundant in the proximal and collecting segments. These cells have cytoplasmic processes and large spherical nuclei. Their cytoplasm appears electron dense and contains many lysosomes, rough endoplasmic reticulum, free ribosomes, some mitochondria and Golgi profiles. Their ultrastructural features indicate that they may be phagocytic.

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Ultrastructural examination of the head kidney of Periophthalmus koelreuteri (Pallas) (Teleostei, Gobiidae) revealed that the nephronic tubule cells are bound by tight junctions and desmosomes with little intercellular space. The first proximal segment (PI) consists of low columnar cells with well developed brush borders, indented nuclei, and numerous apical endocytic vesicles and lysosomes. A second cell type possessing clusters of apical cilia and lacking brush border and lysosomes is occasionally found between PI cells. The second proximal segment (PII) is formed of high columnar cells with brush border, regular spherical nuclei and numerous mitochondria located between well developed infoldings of the basal membrane. Single ciliary structures protrude into the lumen from PI and PII cells. The distal segment is lined by low columnar epithelium with few microvilli, regular spherical nuclei, numerous scattered mitochondria, and microbodies. The collecting tubule cells are cuboidal with few euchromatic nuclei, some mitochondria, and secondary lysosomes.