PubMed Health⌕ Search

Biomedical subjects

H Arima

Publications and source records attributed to H Arima.

At least 19 recordsLinked to original sources
PubMed2000

Impact of Helicobacter pylori infection on gastric cancer incidence in a general Japanese population: the Hisayama study.

BACKGROUND: Several nested case-control studies have reported the potentially causal relationship between Helicobacter pylori infection and the development of gastric cancer. However, there has been no prospective study evaluating this issue. The purpose of this study is to examine the impact of H pylori infection on gastric cancer occurrence in a general Japanese population (Hisayama, Japan) stratified according to sex, using a prospective study design. METHODS: A total of 2602 subjects aged 40 years or older (1070 men; mean age, 57 years; 1532 women; mean age, 59 years) without a history of gastrectomy or gastric cancer were classified according to the status of the serum IgG antibodies to H pylori and observed prospectively for 9 years from 1988. RESULTS: Infection of H pylori was more common in men (71.5%) than in women (62.5%; P<.001). The age-adjusted incidence of gastric cancer for men (5.3 per 1000 person-years) was 4-fold higher than that for women (1.3; P<.001). In men, the age-adjusted incidence of gastric cancer was significantly higher in the subjects with H pylori infection than in those without it (6.2 vs 2.5; relative risk, 2.59 [95% confidence interval, 1.03-6.50]), whereas no significant difference was observed in women (1.2 vs 1.1; relative risk, 0.99 [95% confidence interval, 0.36-2.68]). These results were similar even after controlling for other risk factors in multivariate analysis. It was estimated that 40.1% of gastric cancers for men in this cohort were attributable to H pylori infection. CONCLUSION: A significant relationship exists between infection with H pylori and subsequent occurrence of gastric cancer for men but not for women in this Japanese population.

Adult↗
PubMed2000

Controlled release of a water-soluble drug, captopril, by a combination of hydrophilic and hydrophobic cyclodextrin derivatives.

Parent beta-cyclodextrin (beta-CyD) and 2-hydroxypropyl-beta-CyD (HP-beta-CyD) form 1:1 solid complexes with an orally active angiotensin-converting enzyme inhibitor, captopril, while hydrophobic perbutanoyl-beta-CyD (TB-beta-CyD) forms a solid dispersion or solid solution with the drug. The binary system of captopril/HP-beta-CyD or captopril/TB-beta-CyD and the ternary system of captopril/TB-beta-CyD/HP-beta-CyD in different molar ratios were prepared by the kneading method, and the release behavior of the drug was investigated. The release rate of captopril from the binary HP-beta-CyD system was rather fast, whereas that from the binary TB-beta-CyD system was comparatively slower, the retarding effect being dependent on the amounts of TB-beta-CyD. The release rate from the ternary captopril/TB-beta-CyD/HP-beta-CyD system was slowed down by the addition of small amounts of HP-beta-CyD, whereas the rate became faster as the molar ratio of HP-beta-CyD further increased (>.25 molar ratio). Both water penetration studies and microscopic observation suggested that the retarding effect is attributable to a gel formation of HP-beta-CyD in the TB-beta-CyD hydrophobic matrix. It was difficult to prolong plasma levels of captopril by administering orally either the binary HP-beta-CyD or TB-beta-CyD system in dogs. On the other hand, the ternary captopril/TB-beta-CyD/HP-beta-CyD system (molar ratio of 1:0.5:0.5) gave a plasma profile comparable to that of a commercially available sustained release preparation (Captoril R). Therefore, a combination of HP-beta-CyD and TB-beta-CyD is useful for the controlled release of water-soluble drugs such as captopril.

Absorption↗
PubMed2000

Hemoperitoneum secondary to exophytic leiomyoma: report of a case.

We report herein the case of a 63-year-old male with hemoperitoneum secondary to exogastric leiomyoma. The patient had been receiving anticoagulation therapy for a cerebral embolism and complained of sudden, severe abdominal pain. A sonogram and computed tomography scan showed an exogastric mass and massive ascites. A peritoneal puncture proved the presence of an intraperitoneal hemorrhage. An emergency laparotomy revealed a pedunculated bleeding tumor, thus confirming the preoperative diagnosis of a ruptured exogastric tumor. A microscopic analysis of the excised tumor demonstrated gastric leiomyoma. Other authors have reported hemoperitoneum secondary to gastric myogenic tumors, but no cases of leiomyomas could be found in the literature.

Biopsy, Needle↗
PubMed2000

X-ray crystallographic characterization of nilvadipine monohydrate and its phase transition behavior.

Crystals of nilvadipine monohydrate were obtained from aqueous acetonitrile solution and characterized by powder and single crystal X-ray crystallography and thermal analysis. Water molecules of crystallization exist in nilvadipine monohydrate crystals in a molar ratio of 1:1 (drug-to-water) and were fixed by three hydrogen bonds with two carbonyl groups of the methyl and isopropyl esters, respectively, and one imino group of neighboring nilvadipine molecules. The conformation of the methyl and isopropyl esters in the monohydrate crystal was the reversal of that in the anhydrate crystal due to the presence of hydrogen bonds with water in the former crystal. The monohydrate crystal was slowly converted to the dehydrate at low humidity, and the latter rapidly converted to the former at high humidity. Powder X-ray diffraction studies indicated that the dehydrate retains the original structure of the monohydrate, i.e., a layer structure stacked on the ac plane perpendicular to the b-axis The solubility of the monohydrate in water was lower than that of the dehydrate and anhydrate forms, although the initial dissolution rate of the monohydrate was faster than that of the anhydrate. The present results indicated that the conformation of 1, 4-dihydropyridine-type calcium channel antagonists such as nilvadipine is easily changed by hydrogen bonds with water molecules of crystallization, and the water molecules are mobile through the void spaces formed between the layers in crystals.

Calcium Channel Blockers↗
PubMed2000

Induction of apoptosis in WEHI 231 cells by cationic liposomes.

PURPOSE: Liposomes are of considerable interest as drug carriers and immunoadjuvants. However, few investigators have studied the changes exerted by liposomes in the cells with which they interact. The purpose of this study was to investigate whether liposomes induce apoptosis in B cells. METHODS: The mouse immature B cell line WEHI 231 cells and mouse splenic B cells were treated with liposomes, and the induction of apoptosis was evaluated by monitoring changes in DNA content, DNA fragmentation and chromatin condensation by flow cytometry, agarose gel electrophoresis and by morphological investigation. RESULTS: Cationic liposomes induced apoptosis in WEHI 231 cells, but neutral and anionic liposomes did not. A contact time of 30 min between WEHI 231 cells and cationic liposomes was sufficient to induce apoptosis, and 80% of the cells showed hypodiploid DNA content. Apoptosis induced by cationic liposomes composed of stearylamine was inhibited by addition of the oxidant scavenger, N-acetyl-cysteine. CONCLUSIONS: Cationic liposomes induced apoptosis in WEHI 231 cells, and the production of reactive oxygen species is important in the regulation of apoptosis induced by cationic liposomes. It is well known that cationic liposomes show cytotoxicity, and apoptosis may be one of the causes of this toxicity.

Animals↗
PubMed2000

Vasopressin and oxytocin neurones of hypothalamic supraoptic and paraventricular nuclei co-express mRNA for Type-1 and Type-2 corticotropin-releasing hormone receptors.

The presence of corticotropin-releasing hormone (CRH) receptors type-1 (CRHR-1) and type-2 (CRHR-2alpha) in the hypothalamic supraoptic (SON) and paraventricular (PVN) nuclei, and the effects of i.c.v. injection of CRH and urocortin on arginine vasopressin (AVP) and oxytocin release, have suggested that CRH ligands have a role in osmoregulation. In this study, double labelling in situ hybridization using 35S-labelled CRHR-1 or CRHR-2alpha and digoxigenin-labelled AVP, oxytocin or CRH riboprobes was employed to examine the localization of CRHR-1 or CRHR-2alpha mRNA in the SON and PVN of control and osmotically stimulated rats. Rats received an i.p. hypertonic saline (1.5 M) injection or isotonic saline injection (controls), or 2% NaCl intake (salt loading) or tap water (controls) for 12 days. While CRHR-1 mRNA was undetectable in the SON and PVN in control rats, its expression was increased markedly at 4 h after i.p. hypertonic saline injection or after 12 days salt loading. Of the cells labelled with digoxigenin-AVP, 53% in the SON and 90% in the PVN coexpressed CRHR-1 mRNA after i.p. hypertonic saline injection. In oxytocinergic neurones, 73% in the SON and 91% in the PVN showed CRHR-1 autoradiographic grains higher than background levels after i.p. hypertonic saline injection. In addition, i.p. hypertonic saline induced CRHR-1 mRNA expression in digoxigenin-CRH stained cells in the parvocellular PVN. CRHR-2alpha transcripts were present in both the SON and PVN under basal conditions, and salt loading, but not acute i.p. hypertonic saline injection, further stimulated this expression. Double labelling in situ hybridization showed colocalization of CRHR-2alpha mRNA with AVP and oxytocin mRNA in the SON. These studies support a role for CRH and urocortin regulating the hypothalamo-neurohypophyseal system, and suggest a direct action of the peptides in the magnocellular neurones.

Animals↗
PubMed2000

Improvement of solubility and oral bioavailability of rutin by complexation with 2-hydroxypropyl-beta-cyclodextrin.

The object of this study was to enhance the solubility, dissolution rate, and oral bioavailability of rutin by complexation with 2-hydroxypropyl-beta-cyclodextrin (HP-beta-CyD). The interaction of rutin with cyclodextrins (CyDs) was evaluated by the solubility, and ultraviolet (UV) and circular dichroism (CD) spectrophotometries. The chemical and enzymatic stability of rutin was examined in an alkaline buffer solution and in rat small intestinal homogenates, respectively. Dissolution rates of rutin and its CyD complexes were measured by the dispersed amount method. In vivo absorption studies of rutin after oral administration via conventional tablet containing rutin alone or its beta-CyD complexes was performed on beagle dogs. The stability constants calculated from the phase solubility method increased in the order of HP-gamma-CyD < G2-beta-CyD < beta-CyD < HP-beta-CyD. Spectroscopic studies also revealed that HP-beta-CyD and beta-CyD formed a relatively more stable inclusion complex with rutin. The dissolution rates of rutin increased by the complexation with CyDs in the order of rutin alone < HP-beta-CyD < or = beta-CyD. HP-beta-CyD inhibited the hydrolysis of rutin in the alkaline buffer solution and the small intestinal homogenates of rats, suggesting that HP-beta-CyD may stabilize rutin in a gastrointestinal tract after oral administration. When the tablet containing rutin or its beta-CyD complexes was administered to beagle dogs, the plasma levels of homovanillic acid (HVA) (a major stable metabolite of rutin) after oral administration of HP-beta-CyD complex were much higher than in either that of rutin alone or in its beta-CyD complex. The in vivo absorption study suggests that HP-beta-CyD increased the oral bioavailability of rutin from the gastrointestinal tracts of beagle dogs because of the increase in solubility, faster dissolution rate, and gastrointestinal stability. HP-beta-CyD has a significant advantage with respect to providing high aqueous solubility while maintaining a lack of toxicity in oral pharmaceutical preparations of rutin.

2-Hydroxypropyl-beta-cyclodextrin↗
PubMed2000

Analysis of the vasopressin system and water regulation in genetically polydipsic mice.

Polydipsic mice, STR/N, which show extreme polydipsia and polyuria, were discovered in 1958. In the STR/N, urine outputs are much higher than in control mice. The possibility of an abnormal regulation of the arginine vasopressin (AVP) system, or an abnormality in the renal susceptibility to AVP, should be considered. In this study we investigated the AVP system and water regulation in STR/N. We sequenced the AVP and the AVP V(2)-receptor genes of the STR/N by direct sequencing. No mutation was found in either of them. AVP gene expression examined by in situ hybridization and plasma sodium in 8-wk-old STR/N was significantly lower than in control mice, whereas it was significantly higher at 20 wk. Renal sensitivity to injected AVP was attenuated in 20-wk-old STR/N. The suppression of AVP synthesis due to excessive water retention in 8-wk-old STR/N suggests that polydipsia may be the primary cause in this strain. The 20-wk-old STR/N became dehydrated with the acceleration of AVP synthesis, which might have resulted from secondary desensitization to AVP.

Amino Acid Sequence↗
PubMed2000

Effects of acute hypotensive stimuli on arginine vasopressin gene transcription in the rat hypothalamus.

We investigated the baroregulation of arginine vasopressin (AVP) gene transcription in the supraoptic (SON) and paraventricular nuclei (PVN) in conscious rats by use of intronic in situ hybridization. Hemorrhage of 16 ml/kg body wt decreased mean arterial pressure (MAP) by 57% and increased both plasma AVP (control, 1.2 +/- 0.3 pg/ml; 16 ml/kg body wt, 38.9 +/- 3.2 pg/ml) at 10 min and AVP heteronuclear (hn)RNA levels (SON, 150%; PVN, 140% of control values) at 20 min. On the other hand, hemorrhage of 7 ml/kg body wt had no significant effect on MAP, plasma AVP, or the AVP hnRNA levels. To better understand the baroregulation, we also examined the effects of sodium nitroprusside (SNP), which induces hypotension without a change in blood volume. The subcutaneous injection of 2 mg/kg body wt SNP, which decreased the MAP by 60%, increased both plasma AVP (control, 1.6 +/- 0.4 pg/ml; 2 mg/kg body wt, 8.1 +/- 0.4 pg/ml) at 10 min and AVP hnRNA levels (SON, 150%; PVN, 140% of control values) at 30 min. The injection of 0.1 mg/kg body wt SNP, which reduced the MAP by 10%, failed to increase either the plasma AVP or AVP hnRNA levels. These results indicate that AVP gene transcription increases rapidly after both hypotensive hemorrhage and normovolemic hypotension. In addition, it is suggested that the set point for AVP synthesis in the baroregulation is similar to that for AVP release.

Animals↗
PubMed2000

Improvement of subcutaneous bioavailability of insulin by sulphobutyl ether beta-cyclodextrin in rats.

The objective of this study was to examine and compare how hydrophilic beta-cyclodextrin derivatives (beta-CyDs) improve the bioavailability of insulin following subcutaneous injection of insulin solution in rats. When insulin solutions in the absence of beta-CyDs were injected into the dorsal subcutaneous tissues of rats, the absolute bioavailability of insulin calculated from plasma immunoreactive insulin (IRI) levels was approximately 50%. When maltosyl-beta-cyclodextrin was added to the solutions, there was no change in the plasma IRI levels and hypoglycaemia compared with those of the insulin-alone solution. Dimethyl-beta-cyclodextrin decreased the bioavailability of insulin, although it increased the maximal concentration of IRI in plasma and the capillary permeability of the fluorescein isothiocyanatedextran 40, a non-degraded permeation marker. When insulin solutions containing sulphobutyl ether-beta-cyclodextrin with a degree of substitution of the sulphobutyl group of 3.9 (SBE4-beta-CyD) were injected, the IRI level rapidly increased and maintained higher IRI levels for at least 8 h. The bioavailability of the insulin/SBE4-beta-CyD system was about twice that of insulin alone and approached 96%. The enhancing effects of SBE4-beta-CyD may be in part due to the inhibitory effects of SBE4-beta-CyDs on the enzymatic degradation and/or the adsorption of insulin onto the subcutaneous tissue at the injection site, although this does not apparently facilitate capillary permeability. These results suggest that SBE4-beta-CyD in aqueous insulin injection for subcutaneous administration is useful for improving the bioavailability and the hence the pharmacological effects of insulin.

Animals↗
PubMed2000

Hydrolysis behavior of prednisolone 21-hemisuccinate/beta-cyclodextrin amide conjugate: involvement of intramolecular catalysis of amide group in drug release.

Prednisolone 21-hemisuccinate/beta-cyclodextrin (beta-CyD) amide conjugate was prepared by binding prednisolone 21-hemisuccinate covalently to the amino group of mono(6-deoxy-6-amino)-beta-CyD through amide linkage. Prednisolone 21-hemisuccinate was intramolecularly transformed to prednisolone 17-hemisuccinate, and the parent drug, prednisolone, was slowly released from the 21-hemisuccinate with a half life of 69 h in pH 7.0 at 37 degrees C; the drug release at 25 degrees C was less than 10% for 48 h. In sharp contrast, the hydrolysis of prednisolone 21-hemisuccinate/beta-CyD amide conjugate was significantly faster (half life of 6.50 min at 25 degrees C) and gave prednisolone and mono(6-deoxy-6-succimino)-beta-CyD as products. The hydrolysis of the beta-CyD amide conjugate was subject to a specific-base catalysis in the alkaline region. The rapid hydrolysis of the conjugate can be ascribed to the involvement of an intramolecular nucleophilic catalysis of the amide group in the reaction. The succinic acid, bound to a drug through ester linkage at one carboxylic group and bound to a pro-moiety through amide linkage at another carboxylic group, may be useful as a spacer for construction of the immediate release type prodrugs of CyDs.

Amides↗
PubMed2000

Effects of aging on crystallization, dissolution and absorption characteristics of amorphous tolbutamide-2-hydroxypropyl-beta-cyclodextrin complex.

The effects of storage on the crystallization, dissolution and absorption of tolbutamide from amorphous tolbutamide-2-hydroxypropyl-beta-cyclodextrin (HP-beta-CyD) complex were investigated, in comparison with those of polyvinylpyrrolidone (PVP) solid dispersion. The amorphous solid complex of tolbutamide with HP-beta-CyD and the solid dispersion of tolbutamide with PVP were prepared by a spray-drying method. During storage, a stable form of tolbutamide (form I) was crystallized from the amorphous PVP dispersion, whereas a metastable form of tolbutamide (form II) was crystallized from the HP-beta-CyD complex. The dissolution rate of tolbutamide from both HP-beta-CyD complex and PVP dispersion was significantly faster than that of tolbutamide alone. However, the dissolution rate from the PVP dispersion markedly decreased with storage, because of the formation of slow dissolving form I crystals. On the other hand, the dissolution rate from the HP-beta-CyD complex was only slightly decreased due to the formation of fast dissolving formII crystals. These in vitro dissolution characteristics were clearly reflected in the in vivo absorption of tolbutamide and the glucose plasma level after oral administration in dogs. The results suggested that HP-beta-CyD is useful not only for converting crystalline tolbutamide to an amorphous substance, but also for maintaining the fast dissolution rate of the drug over a long period. Furthermore, the crystallization of drugs from CyD complexes, with storage, seemed to be different from that involving polymer excipients such as PVP.

2-Hydroxypropyl-beta-cyclodextrin↗
PubMed1999

Characterization of itraconazole/2-hydroxypropyl-beta-cyclodextrin inclusion complex in aqueous propylene glycol solution.

The interaction of itraconazole, a triazole antifungal agent, with 2-hydroxypropyl-beta-cyclodextrin (HP-beta-CyD) in water and 10% v/v propylene glycol/water solution at pH 2.0 was investigated by the solubility method and ultraviolet and 1H-nuclear magnetic resonance (NMR) spectroscopies. The solubility of itraconazole in water significantly increased as the concentrations of HP-beta-CyD were augmented, showing an AP type phase solubility diagram. The upward curvature closely corresponded to the simulation curve which was calculated on the basis of the 1:2 (guest:host) complexation model. The 1:2 complex was formed even in the presence of 10% v/v propylene glycol, although the co-solvent system made the interaction with HP-beta-CyD weaker due to the competitive inclusion. The ultraviolet spectroscopic studies also supported the 1:2 complex formation of itraconazole with HP-beta-CyD in 10% v/v propylene glycol/water solution at pH 2.0. The 1H-NMR spectroscopic studies suggested that the triazole and triazolone moieties of itraconazole are involved in the 1:2 inclusion complexation.

2-Hydroxypropyl-beta-cyclodextrin↗
PubMed1999

Cyclodextrins in transdermal and rectal delivery.

Transdermal and rectal routes of drugs are very important as a useful supplement of oral routes and the direct exposing method of drugs when the systemic and local effects are required. The widespread use of parent cyclodextrins (CDs) and chemically modified CD derivatives (CD derivatives) for in-vitro and in-vivo dermal and rectal drug delivery have been evaluated. In addition, the application of hydrophilic CD derivatives to cosmetics have been progressing. In this article, the current status of parent CDs and CD derivatives in the transdermal and rectal delivery of conventional low molecular weight agents are reviewed.

Journal Article↗
PubMed1999

Determination of stability constant of beta-cyclodextrin complexes using the membrane permeation technique and the permeation behavior of drug-competing agent-beta-cyclodextrin ternary systems.

The stability constants (Kc) of beta-cyclodextrin (beta-CyD) complexes with phenacetin and various benzoic acids were determined using the membrane permeation technique using a cellophane membrane permeable for guest molecules which was impermeable for beta-CyD molecules. The permeation rate equations of guests in the presence of beta-CyD in the donor phase were derived and the permeation profiles were analyzed as a function of time to determine the Kc values. The Kc values determined using the membrane permeation technique were in close agreement with those determined by the conventional kinetic method and the solubility method. The membrane permeation technique is of greater advantage than the conventional methods, because in the former method the stability constant can be obtained from only one experimental run by analyzing the permeation data as a function of time. In the latter method, on the other hand, some property changes have to be measured at various CyD concentrations and in turn analyzed as a function of CyD concentration. The permeation profiles of phenacetin of the drug-competing agent-beta-CyD ternary system were estimated by using the stability constants and the experimental curves closely matched the theoretically derived ones.

Algorithms↗
PubMed1999

Heptakis(2,6-di-O-methyl-3-O-acetyl)-beta-cyclodextrin: A water-soluble cyclodextrin derivative with low hemolytic activity.

Acetyl groups were introduced to the hydroxyl groups of heptakis(2, 6-di-O-methyl)-beta-cyclodextrin (DM-beta-CyD), and the resulting heptakis(2,6-di-O-methyl-3-O-acetyl)-beta-CyD (DMA-beta-CyD) was evaluated for the inclusion property and hemolytic activity. It was confirmed by means of NMR and mass spectroscopies that in the DMA-beta-CyD molecule, all seven hydroxyl groups at the 3-position were substituted by acetyl groups. Thus, it has the degree of substitution (DS) of 7, whereas DMA4-beta-CyD with the lower substitution (DS 3.8) was a mixture of components with different DS. The aqueous solubility of DMA-beta-CyD was higher than those of beta-CyD, DM-beta-CyD, and heptakis(2,3,6-tri-O-methyl)-beta-CyD (TM-beta-CyD). The hydrophobicity of the whole molecule, assessed from measurements of surface tension, increased in the order of DM-beta-CyD < DMA-beta-CyD < TM-beta-CyD. The half-life of DMA-beta-CyD for hydrolysis in pH 9.5 and 60 degrees C was about 19 h, and there was only slight liberation of acetic acid in rabbit plasma and carboxylesterase (EC 3.1.1.1) at 37 degrees C. DMA-beta-CyD had an inclusion ability similar to that of TM-beta-CyD for p-hydroxybenzoic acid esters with different alkyl chain lengths and an antiinflammatory drug, flurbiprofen, although it was inferior to that of DM-beta-CyD. The hemolytic activity and rabbit muscular irritation of DMA-beta-CyDs were much weaker than those of DM-beta-CyD: no hemolysis was observed even in the presence of 0.1 M DMA-beta-CyD with DS 7. The results suggest that the water-soluble CyD derivative with superior bioadaptability and inclusion ability can be prepared by properly designing substituents at the 3-position and by optimally controlling their degree of substitution.

Animals↗
PubMed1999

Solid-state 13C nuclear magnetic resonance spectroscopic study on amorphous solid complexes of tolbutamide with 2-hydroxypropyl-alpha- and -beta-cyclodextrins.

PURPOSE: The objective of the study was to obtain structural information of inclusion complexes of tolbutamide with HP-alpha- and -beta-cyclodextrins in amorphous state. METHOD: The solid complexes of tolbutamide with HP-alpha- and -beta-CyDs in molar ratios of 1:1 and 1:2 (guest:host) were prepared by the spray-drying method, and their interactions were investigated by solid-state 13C nuclear magnetic resonance (NMR) spectroscopy. RESULTS: The solid 1:1 and 1:2 tolbutamide/HP-CyD complexes showed halo pattern on the powder X-ray diffractogram and no thermal change in DSC curves, indicating they are in an amorphous state. 13C NMR signals of the butyl moiety were broader than those of the phenyl moiety in the HP-alpha-CyD solid complex, whereas the phenyl moiety showed significantly broader signals than the butyl moiety in the HP-beta-CyD solid complex. As temperature increased, signals of the phenyl carbons became markedly sharper, whereas the butyl carbons only sharpen slightly in the HP-d-CyD complex. In contrast, signals of the butyl carbons became significantly sharper whereas those of phenyl carbons only slightly changed in the HP-beta-CyD complex. CONCLUSIONS: Solid state 13C NMR spectroscopic studies indicated that the butyl moiety of tolbutamide is predominantly included in the HP-alpha-CyD cavity, whereas the phenyl moiety in the HP-beta-CyD cavity in amorphous complexes.

2-Hydroxypropyl-beta-cyclodextrin↗