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Four experiments evaluated the efficacy of Na or Cl or their combination added to weanling pig diets that contained plasma protein and lactose on pig performance and N digestibility. The four experiments used a total of 563 crossbred pigs weaned at 22 + 1 d of age averaging 6.4 kg body weight. The basal diet in each experiment contained 5.8% plasma protein and 20% lactose and analyzed .20% Na and .23% Cl. In Exp. 1, NaCl was added to treatment diets at 0, .20, .40, or .60%. The trial was conducted for a 21 d period in a randomized complete block (RCB) design in seven replicates. Improved growth rates (P < .01) and gain:feed ratios (P < .01) occurred up to a dietary salt level of .40%. In Exp. 2, we evaluated the interaction of Na and Cl on pig performance. The experiment was a 2 x 2 factorial arrangement in a RCB design conducted in seven replicates. Total dietary Na was .20 or .36%, and Cl was included at .25 or .45%. Although there was a numerical increase in pig gains with added Na, the response was not significant (P > .15), but both gains (P < .01) and gain:feed ratios (P < .01) increased at the higher dietary Cl level. In Exp. 3, we evaluated the effect of five dietary levels of Cl added at .06% increments to a basal diet that analyzed .34% Na and .20% Cl on postweaning pig performance. The experiment was a RCB design conducted in eight replicates. A growth response (P < .01) to the .38% Cl level occurred during the initial 14-d postweaning period and to the .32% Cl level from 14 to 21 d. Gain:feed ratio increased each week with added Cl, but it was significant only for the period from d 0 to 7 d (P < .01). A N digestibility trial, using the diets of Exp. 3, constituted Exp. 4, and groups of three pigs per stainless steel metabolism crate were pair-fed to pigs fed the basal diet. The experiment was a RCB design conducted in three replicates over a 3-wk period. The results demonstrated a weekly decrease in fecal N (P < .01), no effect on urinary N (P < .15), improved N retention (P < .01), and an improved apparent N digestibility (P < .01) to the .38% dietary Cl concentration during the initial 2 wk postweaning. These experiments suggest that although plasma protein contributed Na and Cl to the initial diets of weaned pigs, additional Na and Cl, but particularly Cl, improved pig growth, N retention, and N digestibility. The results suggest a dietary minimum of .38% total Cl level during the initial 2 wk postweaning. Key Words: Sodium, Chlorides, Salt, Blood Protein, Pigs

Researchers continue to develop newer types of platinum-based drugs for treating cancer. The most widely use platinum cancer drug is cisplatin, but it has severe side effects and can only be used for certain tumors. Many tumors also become resistant to the drug.

Metal complexes that bind to an enzyme's active site could be used to inhibit the enzyme if excess enzymatic activity is causing disease. However, the metal complex must be specific to that enzyme, must be stable, non-toxic, and bioavailable, and must produce no compensatory effects.

It is not entirely clear how bismuth compounds work therapeutically but they are relatively effective antibacterial agents. They are used most often for gastrointestinal disorders such as dyspepsia and Helicobacter pylori infections.

The exact mechanism of gold drugs is not known, but all known gold drugs form aurocyanide and gold (III) in the body. Gold drugs are used to treat rheumatoid arthritis and bronchial asthma.

British Anti-Lewisite (BAL) should probably be discontinued in favor of newer chelating agents for the treatment of metal intoxication. Two such compounds are meso-2,3-dimercaptosuccinic acid (DMSA) and D,L-2,3-dimercapto-1-propanesulfonic acid (DMPS).

Several vanadium compounds are the subject of research because vanadium can promote glucose uptake by tissues in the same way that insulin does. Compounds of interest include inorganic vanadium salts, vanadium and hydrogen peroxide complexes, and chelated vanadium complexes.

Lithium is widely used to treat certain psychiatric conditions although its exact mechanism is unknown. It is also effective against viral infections, skin diseases, cancer, and AIDS. Whatever the mechanism is, it must affect a fundamental process because lithium is such a simple element.

Inorganic metal complexes may be useful in treating drug-resistant malaria and leishmaniasis. Technetium-sestamibi can be used to identify cancer patients who have a drug-resistant tumor.

Several manganese complexes can mimic the action of superoxide dismutase, which eliminates free radicals. The most effective are Mn(super III)(salen) complexes and Mn(super II)([15]aneN(sub 5)) complexes.

Researchers continue to investigate chemotherapeutic drugs containing other transition metals besides platinum. These investigational drugs are based on ruthenium, rhodium, titanium, vanadium, and tin.

Researchers are still trying to determine exactly how cisplatin destroys cancer cells. The drug binds to DNA and several proteins have been identified that bind to the cisplatin-DNA adduct. These proteins may be involved in the drug's activity against cancer cells.

The effect of metals on the biological activity of photo- and radiosensitizers is discussed. Several metal complexes are under development as photosensitizers for photodynamic therapy.

Cisplatin eventually crosslinks the N7 atoms of two adjacent guanine residues because this reaction is thermodynamically favorable. There are many existing proteins in the cell that have S-donor ligands that can compete in this reaction.

Researchers continue to develop therapeutic radiopharmaceuticals to treat cancer. These drugs preferentially bond to tumor tissue and deliver a dose of radiation to destroy the tumor. This minimizes damage to healthy tissue and reduces the side effects of radiation therapy.

Inorganic chemicals have been used for medicinal purposes since 5,000 B.C. Since many metals perform essential functions in the body, they can be incorporated into drugs. The most well-known example is the chemotherapy drug cisplatin, which contains platinum.

Entomologists during the 18th and 19th centuries recommended a number of organic remedies for insect bites and allergies. Many of these suggested treatments fell out of fashion during the early part of the 20th century in favor of inorganic chemicals. However, growing concern over potential health risks of inorganic chemicals have adversely affected their use. Consequently, some sectors are advocating a return to organic remedies for many minor ailments and afflictions., Miss Muffet should have asked her father Little Miss Muffet sat on a tuffet eating her curds and whey. There came a big spider who sat down beside her and [...]