**5. References**

68 Macro to Nano Spectroscopy

salivary flow was stimulated, the velocity of flow for the UAB was estimated as 2.3

Table 5. Estimated velocity of the salivary film at UAB and UPB sites in the mouth

Lagerlöf and Dawes (1984) measured oral salivary volume immediately before and after the onset of swallowing and reported the mean volumes to be 1.07 and 0.77 ml, respectively. Collins and Dawes (1987) and Watanabe and Dawes (1990) measured the surface area of the mouth, and based on the oral salivary volumes reported by Lagerlöf and Dawes (1984).

estimated the mean thickness of the salivary film in the mouth to be 0.1 mm. The extraoral device on which a 0.1-mm-thick salivary film flows on an agarose gel was designed on the basis of these reports to reproduce the situation in the mouth extraorally. Artificial saliva was allowed to flow onto an agarose gel in the same holder as that used in the mouth at different flow rates to determine the relationship between flow rate and clearance half-time, based on which salivary velocity at the two sites in the mouth was calculated. The velocity estimated with this device appears to be more useful for comparing salivary velocity between the different sites in the mouth than in determining actual salivary velocity. The mean half-time at stimulated salivary flow was 12.1 ± 5.2 min in the present study, which is substantially different from that obtained at unstimulated salivary flow. This may be attributable to the substantial difference in the secretion rate of saliva between when saliva

In clinical dentistry, it is generally accepted that the mandibular front teeth has low caries sensitivity, and the maxillary front teeth has high (e.g. nursing bottle caries) and the caries incidence of the buccal side of teeth in old person is higher than the lingual side. The results

, they

Extraoral device for estimating salivary velocity at both sites:

is unstimulated and stimulated condition.

of this study have confirmed these clinical situations.

**2.5.4 Discussion** 

**3. Conclusion** 

mm/min, whereas for the UPB it was estimated as 12.1 mm/min.


**4** 

*Brazil* 

**An Assay for Determination of** 

**Fresh and Deparaffinized Tissue** 

Raquel Borges Pinto1, Pedro Eduardo Fröehlich2,

*1Post Graduate Program in Medicine: Pediatrics,* 

*Hospital de Clínicas de Porto Alegre,* 

*Universidade Federal do Rio Grande do Sul (UFRGS),* 

**Hepatic Zinc by AAS – Comparison of** 

Ana Cláudia Reis Schneider3, André Castagna Wortmann3, Tiago Muller Weber2 and Themis Reverbel da Silveira1,\*

*2Post Graduate Program in Pharmaceutical Sciences, UFRGS, Porto Alegre, 3Post Graduate Program in Medical Sciences: Gastroenterology and Hepatology,* 

Atomic absorption spectroscopy (AAS) is a reliable method to determine metal concentrations. Zinc is a fundamental trace element because of its role in several essential biochemical functions. It is a component or co-factor of several enzymes, such as alcohol dehydrogenase and superoxide dismutase. It is of fundamental importance in cell division, genetic expression, and physiological processes, such as growth and development, immunity and wound healing; also, it plays a structural role in stabilizing biomembranes

The importance of the determination of the hepatic concentration of certain metals is clearly established in the investigation of hereditary hemochromatosis and Wilson's disease (Pietrangelo, 2003, Roberts et al; 2003). As well, some interesting studies were published on the importance of zinc related to hepatic diseases. Decreases in plasma (Halifeoglu et al., 2004; Schneider et al., 2009; Pereira et al., 2011) or serum (Hamed et al., 2008, Matsuoka et al., 2009) zinc concentrations have been described in patients with chronic liver diseases. Authors that measured zinc in the liver parenchyma of adults and children with liver cirrhosis found low zinc levels (Milman et al., 1986; Göksu & Özsoylu, 1986; Sharda & Bhandari, 1986; Kollmeier et al., 1992; Adams et al., 1994). In patients with alcoholic cirrhosis, studies found abnormal zinc concentrations not only in the liver parenchyma (Rodriguez-Moreno et al., 1997), but also in subcellular fractions of the liver (Bode et al., 1988). In other diseases, such as biliary atresia (Bayliss et al., 1995; Sato et al., 2005), Indian childhood cirrhosis (Bhardwaj et al., 1980; Sharda & Bhandari, 1986), and chronic hepatitis B

**1. Introduction** 

 \*

Corresponding Author

(Hambidge, 2000; Kruse-Jarres, 2001).

(Gür et al., 1998), also were found low liver zinc concentrations.

