Biochemical investigations

The selection of a suitable and relevant organism is an important part of any biochemical investigation. The studies that revealed the secrets of fatty acid synthesis are a good case in point. 

The analogs of pyrimidine and purine bases can be derived by purely formal structural modifications or, more rationally, from the results of biochemical investigation. 

Bivalvia. The bivalve Pholas is historically important because the concept of luciferin-luciferase reaction was established with this clam (Dubois, 1887). It is the only bivalve that is well known and biochemically investigated. The details of the Pholas bioluminescence are given in Section 6.2. 

Despite the relatively common occurrence of luminous echino-derms, only two species of ophiuroid, Ophiopsila califomica and Amphiura filiformis, have been biochemically investigated. It is surprising that the former species luminesces with a photoprotein system, whereas the latter emits light with a luciferin-luciferase system. 

We believe that most if not all diseases are manifestations of abnormalities of molecules, chemical reactions, or biochemical processes. The major factors responsible for causing diseases in animals and humans are hsted in Table 1-2. All of them affect one or more critical chemical reactions or molecules in the body. Numerous examples of the biochemical bases of diseases will be encountered in this text the majority of them are due to causes 5, 7, and 8. In most of these conditions, biochemical smdies contribute to both the diagnosis and treatment. Some major uses of biochemical investigations and of laboratory tests in relation to diseases are summarized in Table 1-3. 

Table 1-3. Some uses of biochemical investigations and laboratory tests in relation to diseases.

From this brief review of marine vertebrate venoms, it is obvious that very few biochemical investigations have been done. The technology to study marine vertebrate venom components is available. There are simply not enough scientists interested enough to enter the field. The first task is to isolate the toxic principles and identify the amino acid sequences. Pharmacological investigation should be done on the purified toxic principle and not on the crude venom, which is a mixture of many proteins and nonproteins. 

The complexity of the problem of hemoglobin heterogeneity has made It necessary to use rather advanced biochemical Investigative procedures. Many analyses require advanced protein chemical techniques. The second part of this review describes some of these methods. 

Most suitable would be the use of a perfectly NH4+ ion-selective glass electrode however, a disadvantage of this type of enzyme electrode is the time required for the establishment of equilibrium (several minutes) moreover, the normal Nernst response of 59 mV per decade (at 25° C) is practically never reached. Nevertheless, in biochemical investigations these electrodes offer special possibilities, especially because they can also be used in the reverse way as an enzyme-sensing electrode, i.e., by testing an enzyme with a substrate layer around the bulb of the glass electrode. 

Sroczynski J, Urbanska-Bonenberg L, Twardowska-Saucha K, et al. 1987. [Biochemical investigations evaluating the health condition of workers chronically exposed to lead.] Med Pr 38 429-436. (Russian)... 

Oldroyd S. M. (1971). Biochemical investigations on various forms of some Papilio species. Entomologist 104 111-123. 

Certain compositional differences between coals of differing origins can be inferred from available data. Differing anatomical distributions of cellulose, lignin and suberin, with implications for the origins of vitrinites, and differing distribution of phenolic substances in plants of different orders and families, have been referred to above. Some biochemical investigations of modern representatives of ancient plants have been made (e.g., refs. 14,... 

In conclusion, in vitro as well as in vivo studies with 3H-LSD revefiled that specific sites which bind the labeled hallucinogen do exist in brain. These sites apparently do not correspond to receptors for hallucinogens but to specific postsynaptic receptors for 5-HT. It can be inferred that serotonergic synapses may be a preferential target for hallucinogens, at least for those of the LSD series. As discussed below, numerous biochemical investigations on brain 5-HT metabolism confirm this hypothesis. 

The protocols are written as a handy guide that can be carried as a pocket guide for easy reference. The protocols are easy to follow with each step explained in layman terms. Even though the field of biochemistry is exhaustive, an effort has been made to list some of the protocols that could serve as a foundation for starting any biochemical investigation. 

Laboratory support is carried out by the clinical diagnostic laboratory and laboratory of tissue typing. The equipment of clinical diagnostic laboratory allows carrying out hematological, biochemical investigations for the structural subdivisions of the Center, coagulometry, analysis of the acid-alkali state, the electrolytes of blood and several other researches in the round-the-clock mode. 

The ribonucleotides of 6-mercaptopurine, 6-thioguanine, 6-chloropurine, and purine have been prepared chemically for biochemical investigations [138-141 ]. 

This section examines the synthesis of nucleosides that contain seven-membered sugar analogues in place of the deoxyribose component. Nucleosides from the last group have been further incorporated into ONs via solid-phase DNA synthesis. A physical and biochemical investigation of the oligomers thus prepared continues in the next section. The study under review culminated in the assessment of the ability of the oligomers to complex with single-stranded RNA and for the heteroduplexes so formed to serve as substrates of RNAseH. 

Freyberger A, Schladt L (2009) Evaluation of the rodent Hershberger bioassay on intact juvenile males— testing of coded chemicals and supplementary biochemical investigations. Toxicology 262(2) 114-120... 

Fig. 5.19. GTP and GDP structures of transducin. The Ga,t subunit of transducin possesses—in contrast to Ras protein and to other small regulatory GTPases —an a-hehcal domain that hides and closes the G-nucleotide binding pocket. The conformational changes that accompany the transition from the inactive G t GDP form (a) into the active G t GTP form (b), are restricted to three structural sections that are known as switches I, II and III. Switch I includes the link of the a-helical domain with P2, switch II affects in particular hehx a2, and switch III, the pS—a3 loop. Switch III includes a sequence that is characteristic for the a-subunits of the heterotrimeric G-proteins. The conformational changes of switches II and III affect structural sections that are assumed to be binding sites for the effector molecule adenylyl cyclase (AC) and the y-subunit of cGMP-dependent phosphodiesterase (PDEy), based on mutation experiments and biochemical investigations. MOLSKRIPT representation according to Krauhs, (1991).

Genetic and biochemical investigations point to a function as a central effector of signal transduction via Ras proteins for the Raf kinase. Raf kinase is immediately downstream from Ras protein in the signal chain. The activated GTP form of Ras protein interacts in a specific manner with Raf kinase and thus mediates membrane localization of Raf kinase. Consequently, the protein kinase activity of Raf kinase is stimulated and the signal is transmitted further via the protein kinase cascade of the MAP kinase pathway. 

Mortensen PB, Hansen HE, Pedersen B, et al. Acute valproate intoxication biochemical investigations and haemodialysis treatment. IntJ Clin Pharmacol Ther Toxicol 1983 21 64-68. 

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