Ovary structure

ESTROGENS (Estradiol being the most important) ORIGIN Ovary STRUCTURE Steroid... 

Vertebrate sex determination occurs in the gonadal prrimordium (the genital ridge), and once it takes place, the gonads are differentiated into specific male (testes) and female (ovaries) structures that, mostly because of their hormone-secretion activity, conscript the body into further sexual differentiation (somatic sexual dimorphism). 

FIGURE 4.1 A schema of the typical flower of cereal grains and the ovary structure showing the ovum and polar nuclei that, upon fertilization, yield the germ and endosperm tissues. 

Progestins are derived from the 21-carbon series and contain as a basic structure the pregnane nucleus. In the non-pregnant female they are mainly produced in the ovary. 

The equivalent of the tryptic fragment of human transferrin receptor has been expressed in Chinese hamster ovary cells and its structure determined at a resolution of 0.32 nm (Lawrence et ah, 1999). The asymmetric unit of the crystals contains four transferrin receptor dimers. Interpretable electron density is found for the entire tryptic fragment except for Arg-121 at the amino terminus, and density is also seen for the first N-acetylglucosamine residue at each of the N-glycosylation sites. The transferrin receptor monomer is made up of three distinct domains, organized such that the dimer is butterfly shaped (Figure 5.10, Plate 7). The likely orientation of the dimer with respect to the plasma membrane has been assigned on the basis of the... 

Nomura and Ogata provided the first evidence that tunicates can produce PGs [17]. Using a rat stomach fundus bioassay, Halocynthia roretzi tissues were shown to possess low levels of PGs. The testes showed higher levels (9 ngg-1 wet tissue) than ovary and muscle tissue. The sea-squirt Styela clava did not show PGs by this method. No structures were determined in this work. Reexamination of the ability of H, roretzi to produce PGs was carried out by Ogata and coworkers [19]. Incubation of selected tissues with 14C-labeled eicosa-8,11,14-trienoic acid and subsequent isolation of PGE and PGF fractions after addition of carrier showed the branchial tissue to have the highest conversion levels. Quantitation was done by LSC. Using a TLC radioscanner, the authors determined that fractions with metabolites similar to PGE and PGF... 

Many of the initial biopharmaceuticals approved were simple replacement proteins (e.g. blood factors and human insulin). The ability to alter the amino acid sequence of a protein logically coupled to an increased understanding of the relationship between protein structure and function (Chapters 2 and 3) has facilitated the more recent introduction of several engineered therapeutic proteins (Table 1.3). Thus far, the vast majority of approved recombinant proteins have been produced in the bacterium E. coli, the yeast S. cerevisiae or in animal cell lines (most notably Chinese hamster ovary (CHO) cells or baby hamster kidney (BHK) cells. These production systems are discussed in Chapter 5. 

Ovary, Z., Passive cutaneous anaphylactic reactions as tools in the study of the structure of the IgG molecule, Mol. Immunol., 15, 751, 1978. 

A second study examined the effects of DMBA initiated mi rex-promoted tumors in female mice on ovarian hormones. This study found that the loss of ovary (OVX) protected the female mice (40%) from mirex tumor promotion. Tumor promotion was unaffected in DMBA-initiated OVX mice promoted with TPA. Based on the data, the authors also concluded that there is a structural specificity in the tumor-promoting ability of mirex in mouse skin and that mirex is a much more effective skin tumor promoter in female CD-1 mice than in male CD-1 mice or OVX mice (Meyer et al. 1994). 

One of the applications of CE for carbohydrate analysis that has shown increase acceptance in the biotechnology industry is the relative distribution of the N-linked oligossacharides on the conserved asparagines residue on the Fc portion of rMAbs. The advantages of CE over traditional methods include enhanced separation efficiencies, shorter analysis time, and improved robustness. The oligosaccharides present on a monoclonal antibody are asialo-N-linked complex biantennary structures with a core fucose, typical of the structures produced in the Chinese hamster ovary (CHO) cells. The main forms share the fucosylated branched core structure but vary in their terminal galactose occupancy ... 

Like living organisms themselves, cells come in a remarkable variety of flavors. Brown has described what might be a human cell with elaborate internal structure. However, there is no such a thing as a typical cell. Afunctional liver cell, a hepatocyte, is quite distinct from a nerve cell, a neuron, that, in turn, is not much like a cell of the retina of the eye. Skin cells, pancreatic cells, kidney cells, cells of the testis and ovary, red blood cells, bone cells, and on and on, are all structurally, functionally, and metabolically distinct. Indeed, there are several types of cells in the skin, pancreas, kidney, testis, ovary, and bone. Then there are the cells of bacteria and other microorganisms that have no nucleus or other membrane-limited organelles very different. Diversity abounds. 

This is an unusual drug in that it contains a metal atom, platinum (Pt) in this case. Cisplatin reacts with DNA to cross-link bases, disrupting normal DNA structure and function. This agent has found broad use in cancer chemotherapy, including efficacy in tumors of the testis, ovary, bladder, head and neck, thyroid, cervix, and endometrium. It is also active against neuroblastoma and osteogenic sarcoma. 

Pioneering studies were made to determine the structure of tetrodotoxin 1, one of the most toxic compounds among the low-molecular-weight poisons, found in the ovaries and liver of puffer fish, which is a highly esteemed delicacy in Japan. With a combination of the most versatile instrumental facilities, the complex perhydroquinazoline structure of 1 was established (65T2059) in the early 1960s. 

A crude toxic principle, which we now know to be only about 0.2% pure, was obtained by Yoshizumi Tahara (9,10) in 1909. He named this tetrodotoxin. In 1950 Aikira Yokoo (11) obtained pure crystalline tetrodotoxin. The purification was further developed by Tsuda and co-workers (12) so that the production of the necessary amounts of tetrodotoxin for structural and chemical studies could be achieved. From 1000 kg (1 ton) of pufferfish ovaries they obtained 8-10 g of tetrodotoxin. 

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