Lobule

Fig. 13.3 Triple immunostaining of a an immature lobule for K5 (red) and K8/18 (green), and SMA (pink) acini contain mainly immature epithelium (K5, red) and only few differentiated cells express K8/18 (green)...

Fig. 13.4 Triple immunostaining of a mature lobule for K8/18 (red), K5 (green) and SMA (pink). Note that most of the acini contain K8/18 only one acinus contains intermediate cells (arrow, hybrid orange color)...

G.R. Cannell, R.M. Kluck, S.E. Hamilton, R.H. Mortimer, W.D. Hooper, and R.G. Dickinson. Markers of physical integrity and metabolic viability of the perfused human placental lobule. Clin Exp Pharmacol Physiol. 15 837-844 (1988). 

I. M. Anundi, F. C. Kauffman, M. El-Mouelhi, R. G. Thurman, Hydrolysis of Organic Sulfates in Peripheral and Pericentral Regions of the Liver Lobule Studies with 4-Meth-ylumbelliferyl Sulfate in the Perfused Rat Liver , Mol. Pharmacol. 1986, 29, 599 - 605. 

Fig. 1. Indirect in situ RT-PCR for ras mRNA in normal and neoplastic human breast tissues. (A) and (C) Negative controls for ras message. (B) Detection of ras mRNA signal in normal epithelial cells of mammary duct and lobules. (D) Detection of ras mRNA signal in neoplastic ductal epithelial cells in breast tissue with ductal carcinoma in situ (DCIS).

Classically the liver has been divided into hexagonal lobules centred around the terminal hepatic venules. Blood enters the liver through the portal tracts that are situated at the corners of the hexagon. The portal tracts are triads of a portal vein, an hepatic artery, and a common hepatic bile duct. The vast expanse of hepatic tissue, mostly consisting of parenchymal cells (PC) or hepatocytes, is serviced via terminal branches of the portal vein and hepatic artery, which enters the tissue at intervals. The hepatocytes are organized into cords of cells radially disposed about the central hepatic venule. Between these cords are vascular sinusoids that transport the blood to the central hepatic venules. The blood is collected through the hepatic venules into the hepatic vein which exits the liver into the inferior vena cava (Figure 4.1). 

Decreases in the relative weights of the lymph nodes and thymus were noted in male mice following daily dermal exposures for 1 week to 0.1 mL kerosene (Upreti et al. 1989). In addition, thymocyte counts, bone marrow nucleated cell counts, thymic cortical lymphocytes, and the cellularity of the thymic lobules were decreased. Increases in the cellular populations of the popliteal lymph nodes and the axial lymph nodes were also present. This study is limited because females were not tested. Chronic exposure to 500 mg/kg/day JP-5 induced granulocytic hyperplasia in the bone marrow in male and female mice and hyperplasia in the lymph nodes of female mice (NTP/NIH 1986). Plasmacytosis of the lymph nodes was found to be secondary to dermatitis in mice chronically exposed to 250 and 500 mg/kg/day of marine diesel fuel. 

Studies in mice have shown that selective covalent binding of VDC occurs in the proximal tubules, the liver lobules, and the mucosa of the upper respiratory tract and corresponds to sites of potential toxicity. Additional events such as depletion of glutathione appear to be necessary for VDC-induced cell death to occur. 

Apoptosis Nuclear condensation and lobulation, caspase activation, phosphatidyl serine externalization, annexin, immuno-cytochemistry, DNA fragmentation and labeled-dUTP incorporation by terminal deoxynucleotidyl transferase... 

Chemomodulatory influence. Asafetida, administered orally to Sprague-Dawley rats at doses of 1.25% and 2.5% w/w in diet, produced an increase in the development and differentiation of ducts/ductules and lobules and a decrease in terminal end buds as compared to both normal and N-methyl-N-nitrosourea-treated control animals. Asafetida treatment significantly reduced the levels of cytochrome P450 and b5. There was an enhancement in the activities of glutathione-S-transferase, deoxythymi-dine-diaphorase, superoxide desmutase, catalase, and reduced glutathione " " . Central nervous (CNS) effects. Ethanol extract of the dried gum, administered orally to adults at a dose of 20 mL/person, was active "" . 

Testicular degeneration (spermatogonial activity reduced, germ cells in testicular lobules degenerating, congested blood vessels) ovaries histologically different, oocytes resorbed... 

With in pancreatic polypeptide-rich lobules of adult islets, located only in the posterior portion of the head of the human pancreas, glucagon cells are scarce (< 0.5%) and F cells make up as much as 80% of the cells. 

The liver contains an enormous number of hepatocytes that perform the various functions noted above. The hepatocytes are contained within minute units known as hepatic lobules, in which the cell layers (which are one or two cells thick) are in contact with networks of minute blood channels - the sinusoids - which ultimately join the venous capillaries. Capillaries carrying blood from the hepatic artery and the portal vein empty separately into the sinusoids. The walls of sinusoids and liver cells are incomplete, and blood is brought into direct contact with the hepatocytes. 

The bile canaliculi form a network, which feed into ductules, which become bile ducts (Fig. 6.3). The structural and functional unit of the liver is the lobule, which is usually described in terms of the hepatic acinus (Fig. 6.5), based on the microcirculation in the lobule. When the lobule is considered in structural terms, it may be described as either a classical or a portal lobule (see "Glossary"). The acinus comprises a unit bounded by two portal tracts and terminal hepatic or central venules, where a portal tract is composed of a portal venule, bile ductile, and hepatic arteriole (Fig. 6.5). Blood flows from the portal tract toward the central... 

Which of the following are true Compared with zone 1, zone 3 of the liver lobule has... 

Newman SF, Sultana R, Perluigi M, Coccia R, Cai J, Pierce WM, Klein JB, Turner DM, Butterfield DA. 2007. An increase in S-glutathionylated proteins in the Alzheimer s disease inferior parietal lobule, a proteomics approach. J Neurosci Res 85 1506-1514. 

Another advantage of immunohistochemistry is that tissues of a small size (e.g., biopsies) can be used. This is important because it is better to detect tumors at an early stage, when they are small. The necessity of early detection cannot be overemphasized. Very small tumors and fine-needle aspirates cannot be used for biochemical assays. Although the DCC assay provides quantitative results, it does not take into account the relative amount of the connective tissue in the specimen, the presence of carcinoma in situ lesions, or normal ducts and lobules. These limitations are not encountered when using paraffin sections. In addition, immunohistochemistry allows the use of archival tissues when fresh tissues are not available. This method does not require any special, expensive equipment and can be carried out in any standard laboratory. 

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