Abstract: A novel amino acid transporter molecule mediating transportation of amino acids, which are nutrients essentially required in the survival and proliferation of various normal cells constituting a living body and various pathology-associated abnormal cells such as tumor cells, into cells and being expressed specifically in tumor cells compared with normal cells; and drugs for treating various pathogenic conditions such as tumor (cancer) which are obtained by identifying and isolating the above amino acid transporter molecule and identifying a substance capable of inhibiting the biological activity and/or expression of this molecule. Intensive studies were made to identify a tumor cell membrane surface molecule associating or interacting with a cell membrane surface 4F2hc molecule seemingly playing an important role in the activation of an unknown amino acid transporter.

Abstract: It is intended to identify and provide a novel urate transporter gene participating in the urate transport in the kidney and a urate transporter which is a polypeptide encoded by the above gene. Namely, a protein comprising the amino acid sequence represented by SEQ ID NO:1 or an amino acid sequence derived therefrom by deletion, substitution or addition of one to several amino acids and being capable of transporting uric acid and its analogs; and a gene encoding this protein.

Abstract: A novel organic anion transporter gene participating in organic anion transport in the placenta; and an organic anion transporter which is a polypeptide encoded by the gene. A placental organic anion transporter OAT4, more particularly, a placental organic anion transporter OAT4 having the amino acid sequence represented by SEQ ID NO:2 or an amino acid sequence derived therefrom by deletion, substitution or addition of a part of the amino acids thereof. A nucleic acid (preferably DNA) having a base sequence encoding the placental organic anion transporter OAT4 or a base sequence hybridizable therewith under stringent conditions.

Abstract: Novel sodium-independent small neutral amino acid transporters which transport L- and D-amino acids. A protein comprising the amino acid sequence represented by SEQ ID NO:1 or 4 or an amino acid derived therefrom by deletion, substitution or addition of one or more amino acids and being capable of sodium-independently transporting L- and D-small neutral amino acids and analogs thereof; a gene encoding the above protein; a method of screening substances inhibiting or promoting the function of the above protein; an antibody against the above protein; and a method of regulating cell function by using the above antibody, function inhibitors, function promoters, etc.

Abstract: A novel organic anion transporter gene participating in organic anion transport in the placenta; and an organic anion transporter which is a polypeptide encoded by the gene. A placental organic anion transporter OAT4, more particularly, a placental organic anion transporter OAT4 having the amino acid sequence represented by SEQ ID NO:2 or an amino acid sequence derived therefrom by deletion, substitution or addition of a part of the amino acids thereof. A nucleic acid (preferably DNA) having a base sequence encoding the placental organic anion transporter OAT4 or a base sequence hybridizable therewith under stringent conditions.

Abstract: Hydantoin derivatives for eliminating free radicals and active oxygen which can be easily made into pharmaceutical preparations, show little, if any side effects, and are capable of being administered by the oral route. The pharmaceutical compositions for eliminating the active oxygen and the free radicals contain at least one hydantoin derivative represented by the following formula (I): wherein each of R1 and R2, which may be the same or different, represents hydrogen, an alkyl group or a cycloalkyl group; and each of X and Y, which may be the same or different, represents hydrogen, a hydroxyl group, an alkyl group or an alkoxy group, or X and Y together represent an oxo group. The hydantoin derivatives which have an action of eliminating the active oxygen and the free radicals are, accordingly, useful as pharmaceutical agents for treating a variety of diseases in which active oxygen and free radicals are involved or play a detrimental role.

Abstract: Molten metal is poured into a mold having an inside cross section with varied thicknesses along the direction of the width thereof. The molten metal is allowed to solidify in the mold and the cast strip is withdrawn from the mold either continuously or intermittently. The as-cast strip is rolled at either identical or similar thickness reduction ratios in the direction of width of the strip. This process enables the production of high quality shape strips free from any substantial working deformation in the workpiece.