Abstract: Provided is siRNA effective for the treatment of fibrosis and a pharmaceutical containing the siRNA. An siRNA having a full length of 30 or fewer nucleotides and targeting a sequence consisting of 17 to 23 consecutive bases selected from the group consisting of bases at positions 1285 to 1318, bases at positions 1398 to 1418, bases at positions 1434 to 1463, bases at positions 1548 to 1579, bases at positions 1608 to 1628, bases at positions 1700 to 1726, bases at positions 1778 to 1798, bases at positions 1806 to 1826, and bases at positions 1887 to 1907 of SEQ ID NO: 1.

Abstract: An object of the present invention is to provide a liposome which is excellent in intrapulmonary delivery controllability of drugs or genes and is suited for pulmonary administration. By modifying the surface of a liposome using a terminal hydrophobized polyvinyl alcohol and/or chitosan, retention of drugs or genes encapsulated in the liposome on the surface of lung tissue and transfer of drugs or genes into lung tissue can be properly modulated, and thus in vivo behavior can be controlled.

Abstract: An object of the present invention is to provide a liposome which is excellent in intrapulmonary delivery controllability of drugs or genes and is suited for pulmonary administration. By modifying the surface of a liposome using a terminal hydrophobized polyvinyl alcohol and/or chitosan, retention of drugs or genes encapsulated in the liposome on the surface of lung tissue and transfer of drugs or genes into lung tissue can be properly modulated, and thus in vivo behavior can be controlled.

Abstract: Provided is siRNA effective for the treatment of fibrosis and a pharmaceutical containing the siRNA. An siRNA having a full length of 30 or fewer nucleotides and targeting a sequence consisting of 17 to 23 consecutive bases selected from the group consisting of bases at positions 1285 to 1318, bases at positions 1398 to 1418, bases at positions 1434 to 1463, bases at positions 1548 to 1579, bases at positions 1608 to 1628, bases at positions 1700 to 1726, bases at positions 1778 to 1798, bases at positions 1806 to 1826, and bases at positions 1887 to 1907 of SEQ ID NO: 1.

Abstract: The present invention provides a nucleic acid complex with low toxicity and high safety that can persistently maintain a nucleic acid, such as siRNA or the like, in a cell; and a nucleic acid delivery composition that can efficiently deliver the nucleic acid complex into a cell. A nucleic acid complex with low toxicity and high safety that can persistently maintain a nucleic acid in a cell can be obtained by forming a complex using a nucleic acid to be introduced into a cell, and a highly branched cyclic dextrin. Moreover, when a carrier comprising (A) a diacylphosphatidylcholine, (B) cholesterol and/or a derivative thereof, and (C) an aliphatic primary amine is used as a nucleic acid delivery carrier to introduce the nucleic acid complex into a cell, the safety, the efficiency of intracellular delivery, and the persistence of the nucleic acid in the cell can be further improved.

Abstract: An object of the present invention is to provide a nucleic acid delivery carrier composition of low toxicity and high safety, the carrier composition, when used to administer a nucleic acid such as an siRNA into an animal-derived cell or organism, being capable of delivering efficiently the nucleic acids into the cells while protecting it from being degraded; and a nucleic acid deliver composition containing the carrier and a nucleic acid. The carrier composition for delivery of a nucleic acid is prepared by mixing (A) a cationic lipid having a steroid skeleton with (B) a tertiary ammonium salt-type cationic lipid. The nucleic acid delivery composition is prepared by mixing the nucleic acid delivery carrier with a nucleic acid.

Abstract: An object of the present invention is to provide a novel double-stranded RNA that has high resistance to nuclease and cellular uptake efficiency and that can produce an excellent RNA interference effect. The present invention provides a double-stranded lipid-modified RNA comprising a sense strand having a nucleotide sequence complementary to a target sequence in a target gene, and an antisense strand having a nucleotide sequence complementary to the sense strand, the double-stranded RNA being capable of suppressing the expression of the target gene, and the sense strand having a double-stranded lipid bound directly or via a linker to at least one of the first to sixth nucleotides from the 5? end.

Abstract: The present invention provides a nucleic acid complex with low toxicity and high safety that can persistently maintain a nucleic acid, such as siRNA or the like, in a cell; and a nucleic acid delivery composition that can efficiently deliver the nucleic acid complex into a cell. A nucleic acid complex with low toxicity and high safety that can persistently maintain a nucleic acid in a cell can be obtained by forming a complex using a nucleic acid to be introduced into a cell, and a highly branched cyclic dextrin. Moreover, when a carrier comprising (A) a diacylphosphatidylcholine, (B) cholesterol and/or a derivative thereof, and (C) an aliphatic primary amine is used as a nucleic acid delivery carrier to introduce the nucleic acid complex into a cell, the safety, the efficiency of intracellular delivery, and the persistence of the nucleic acid in the cell can be further improved.

Abstract: An object of the present invention is to provide a novel double-stranded RNA that has high nuclease resistance and high cellular uptake efficiency, and that is capable of producing an excellent RNA interference effect. The present invention provides a lipid-modified double-stranded RNA comprising a sense strand having a nucleotide sequence complementary to a target sequence, and an antisense strand having a nucleotide sequence complementary to the sense strand, the double-stranded RNA being capable of inhibiting the expression of the target gene, the sense strand having a lipid linked to at least one of the first to sixth nucleotides from the 5? end side directly or via a linker.

Abstract: The present invention relates to a single-chain circular RNA having a sustained or slow-releasing RNA interference effect, characterized in that the single-chain circular RNA comprises a sense strand sequence, an antisense strand sequence complementary to the sense strand sequence, identical or different two loop sequences between the sense strand and the antisense strand, connecting both strands, wherein the sense strand and the antisense strand are paired to form a stem.

Abstract: An object of the present invention is to provide a liposome which is excellent in intrapulmonary delivery controllability of drugs or genes and is suited for pulmonary administration. By modifying the surface of a liposome using a terminal hydrophobized polyvinyl alcohol and/or chitosan, retention of drugs or genes encapsulated in the liposome on the surface of lung tissue and transfer of drugs or genes into lung tissue can be properly modulated, and thus in vivo behavior can be controlled.

Abstract: An object of the present invention is to provide a carrier composition for nucleic acid delivery, which can efficiently deliver a nucleic acid into cells when a nucleic acid such as siRNA is administered to animal-derived cells or animals, and also has low toxicity and high safety, and a composition for nucleic acid delivery containing the carrier composition and nucleic acid. A carrier for nucleic acid delivery is prepared by using (A) a diacylphosphatidylcholine, (B) at least one member selected from the group consisting of cholesterol and derivatives thereof, and (C) an aliphatic primary amine. Also, a composition for nucleic acid delivery is prepared by mixing the carrier for nucleic acid delivery with a nucleic acid.

Abstract: An object of the present invention is to provide a nucleic acid delivery carrier composition of low toxicity and high safety, the carrier composition, when used to administer a nucleic acid such as an siRNA into an animal-derived cell or organism, being capable of delivering efficiently the nucleic acids into the cells while protecting it from being degraded; and a nucleic acid deliver composition containing the carrier and a nucleic acid. The carrier composition for delivery of a nucleic acid is prepared by mixing (A) a cationic lipid having a steroid skeleton with (B) a tertiary ammonium salt-type cationic lipid. The nucleic acid delivery composition is prepared by mixing the nucleic acid delivery carrier with a nucleic acid.

Abstract: The present invention provides a pharmaceutical preparation that can improve absorption of a pharmaceutical compound in the gastrointestinal tract and that provides, through oral administration or like method, a blood concentration from which sufficient remedial effects can be expected, and a method for producing such a preparation. The invention is directed to a pharmaceutical preparation exhibiting excellent gastrointestinal absorbability comprising a compound recognized by a proton-coupled transporter and a pH-sensitive polymer in an amount sufficient for the gastrointestinal tract to acquire a pH at which the proton-coupled transporter optimally absorbs the compound into a cell.

Abstract: The present invention provides a pharmaceutical preparation that can improve absorption of a pharmaceutical compound in the gastrointestinal tract and that provides, through oral administration or like method, a blood concentration from which sufficient remedial effects can be expected, and a method for producing such a preparation. The invention is directed to a pharmaceutical preparation exhibiting excellent gastrointestinal absorbability comprising a compound recognized by a proton-coupled transporter and a pH-sensitive polymer in an amount sufficient for the gastrointestinal tract to acquire a pH at which the proton-coupled transporter optimally absorbs the compound into a cell.

Abstract: The present invention provides a pharmaceutical preparation that can improve absorption of a pharmaceutical compound in the gastrointestinal tract and that provides, through oral administration or like method, a blood concentration from which sufficient remedial effects can be expected, and a method for producing such a preparation. The invention is directed to a pharmaceutical preparation exhibiting excellent gastrointestinal absorbability comprising a compound recognized by a proton-coupled transporter and a pH-sensitive polymer in an amount sufficient for the gastrointestinal tract to acquire a pH at which the proton-coupled transporter optimally absorbs the compound into a cell.