Enantiomeric 3-Chloromandelic Acid System: Binary Melting Point Phase Diagram,Ternary Solubility Phase Diagrams and Polymorphism

A systematic study of binary melting point and ternary solubility phase diagrams of the enantiomeric 3-chloromandelic acid (3-ClMA) system was performed under consideration of polymorphism. The melting point phase diagram was measured by means of thermal analysis, that is, using heat-flux differential scanning calorimetry (DSC). The results reveal that 3-ClMA belongs to the racemic compound-forming systems. Polymorphism was found for both the enantiomer and the racemate as confirmed by X-ray powder diffraction analysis. The ternary solubility phase diagram of 3-ClMA in water was determined between 5 and 50°C by the classical isothermal technique. The solubilities of the pure enantiomers are extremely temperature- dependent. The solid-liquid equilibria of racemic 3-ClMA are not trivial due to the existence of polymorphism. The eutectic composition in the chiral system changes as a function of temperature. Further, solubility data in the alternative solvent toluene are also presented. © 2010 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 99:4084–4095, 2010     

Solubility Behavior,Phase Transition,and Structure-Based Nucleation Inhibition of Etanidazole in Aqueous Solutions

Purpose. The solubility behavior, phase transition and inhibition of the nucleation process of etanidazole were characterized. Methods. Solubility measurements as a function of time permitted characterization of the solubility behavior and phase transition. The precipitate from saturated solutions was isolated and characterized by differential scanning calorimetry, polarized light microscopy, x-ray powder diffraction and coulometric analysis. The physical stability of metastable systems was examined in the presence of various structure-based nucleation inhibitors. Results. Etanidazole is soluble in water with an equilibrium solubility of 68.1 mg/mL, pH 6.5 with changes in pH having virtually no effect on the solubility. Etanidazole reaches concentrations in excess of 150 mg/mL within one hour. Etanidazole solutions prepared at 150 mg/ mL contained crystals after rotating for 24 hours. The crystals were isolated and characterized as etanidazole monohydrate. The solubility of etanidazole monohydrate in water increased with time reaching an equilibrium solubility of 68 mg/mL after 24 hours. Therefore, the solubility studies were actually determining the solubility of the more stable monohydrate form of etanidazole. Etanidazole solutions at concentrations of 50, 100 and 150 mg/mL were stabilized to varying degrees with structure-based nucleation inhibitors (imidazole, ethanolamine or diethanolamine). Conclusions. Anhydrous etanidazole undergoes a transition in aqueous solutions to the more stable monohydrate when the solubility of the monohydrate is exceeded. The physical stability of etanidazole solutions at 4°C is improved following autoclaving. The addition of structure-based nucleation inhibitors effectively stabilized the metastable systems.     

Polymorphism in CYP1A1, GSTMI, GSTT1 genes and organochlorine pesticides in the etiology of hypospadias

Exposure to endocrine-disrupting chemicals (EDCs) and maternal endogenous estrogen may cause hypospadias, common congenital anomaly. Several organochlorine pesticides (OCPs) have been reported to possess an endocrine-disrupting potential. Cytochrome P4501A1 (CYP1A1) and glutathione S-transferases (GSTM1 and GSTT1) of xenobiotic metabolizing enzyme family are involved in the metabolism of various environmental toxicants and steroidal hormones. Hence, the present study was designed to evaluate the role of CYP1A1, GSTM1, GSTT1 genes polymorphism, OCPs levels and risk of hypospadias. A total of 80 hypospadiac and 120 age-matched control boys were included. OCP levels in blood were determined using Gas Chromatograph equipped with electron capture detector (GC-ECD) and polymorphism in CYP1A1, GSTM1 and GSTT1 genes was evaluated by RFLP and multiplex PCR method. We observed significant high levels of β-hexachlorohexane (HCH), γ-HCH, and p,p'-dichlorodiphenyl-dichloroethylene (p,p'-DDE) in the cases. CYP1A1 polymorphisms were not significantly different among cases and controls, whereas concomitant deletion of GSTM1 and GSTT1 genotypes was significantly higher in cases as compared to controls. However, after adjusting for low birth weight and maternal occupational exposure, the results did not remain significant but odds of risk was higher (OR = 1.72, p = 0.14) among cases. In conclusion, our study suggests irrespective of genetic predisposition, higher level of some OCPs may be associated with increased risk of hypospadias.     

SLCO1B1 Polymorphism and Oral Antidiabetic Drugs

Abstract: Organic anion‐transporting polypeptide 1B1 (OATP1B1; gene: SLCO1B1) is an influx transporter expressed on the sinusoidal membrane of human hepatocytes, where it mediates the uptake of its substrates from blood into liver. In vitro, the SLCO1B1 c.521T > C (p.Val174Ala) single‐nucleotide polymorphism (SNP) has been associated with reduced and the c.388A > G (p.Asn130Asp) SNP with both enhanced and reduced transport activity of OATP1B1. In vivo in humans, the c.521C allele (present in SLCO1B1*5 and *15 haplotypes) is associated with decreased hepatic uptake and increased plasma concentrations of several OATP1B1 substrates. The SLCO1B1*1B (c.388G‐c.521T) haplotype is associated with enhanced hepatic uptake and decreased plasma concentrations of some OATP1B1 substrates. The SLCO1B1 c.521CC genotype has been associated with an about 60‐190% increased, and the SLCO1B1*1B/*1B genotype with an about 30% decreased area under the plasma concentration‐time curve of repaglinide. Moreover, SLCO1B1 polymorphism can affect the extent of interaction between OATP1B1 inhibitors and repaglinide. Accordingly, SLCO1B1 genotyping may help in choosing the optimal starting dose of repaglinide. In Chinese individuals, the SLCO1B1 c.521C allele has been associated with increased plasma concentrations of nateglinide, but the association could not be replicated in Caucasians. SLCO1B1 genotype has had no effect on the pharmacokinetics of rosiglitazone, pioglitazone or their metabolites. The hepatic uptake of metformin is mediated by organic cation transporters 1 and 3, and the liver is not important for the elimination or action of the dipeptidylpeptidase 4 inhibitors sitagliptin, vildagliptin and saxagliptin. Therefore, SLCO1B1 polymorphism unlikely affects the response to these antidiabetics. Possible effects of SLCO1B1 polymorphism on sulfonylureas remain to be investigated.     

主动靶向脂质体的相变温度与靶细胞摄取的相关性研究

分别采用二硬脂酰磷脂酰胆碱(DSPC)、氢化大豆磷脂(HSPC)、二棕榈酰磷脂酰胆碱(DPPC)和二肉豆蔻酰磷脂酰胆碱(DMPC)为载体,制备了NGR肽(Asn-Gly-Arg)修饰的主动靶向脂质体,并用其负载香豆素-6.结果表明,4种脂质体的粒径为120～160 nm,粒度分布均匀,ζ电位接近中性,包封率均在95％以上.差示扫描量热分析(DSC)表明,4种脂质体的相变温度(Tm)值由高至低分别为DSPC脂质体＞HSPC脂质体＞DPPC脂质体＞DMPC脂质体.以CD13高表达的HT1080细胞为模型,采用流式细胞仪、激光共聚焦显微镜观察评价脂质体的入胞效果.结果显示,脂质体的入胞效率与Tm值呈正相关.     

Crystallization of D-Mannitol in Binary Mixtures with NaCl: Phase Diagram and Polymorphism

PURPOSE: To study the crystallization, polymorphism, and phase behavior of D-mannitol in binary mixtures with NaCl to better understand their interactions in frozen aqueous solutions. METHODS: Differential scanning calorimetry, hot-stage microscopy, Raman microscopy, and variable-temperature X-ray diffractometry were used to characterize D-mannitol-NaCl mixtures. RESULTS: NaCl and D-mannitol exhibited significant melt miscibility (up to 7.5% w/w or 0.20 mole fraction of NaCl) and a eutectic phase diagram (eutectic composition 7.5% w/w NaCl; eutectic temperature 150 degrees C for the alpha and beta polymorphs of D-mannitol and 139 degrees C for the delta). The presence of NaCl did not prevent mannitol from crystallizing but, depending on sample size, affected the polymorph crystallized: below 10 mg, delta was obtained; above 100 mg, alpha was obtained. Pure mannitol crystallized under the same conditions first as the delta polymorph and then as the a polymorph, with the latter nucleating on the former. KCl showed similar eutectic points and melt miscibility with D-mannitol as NaCl. LiCl yielded lower eutectic melting points, inhibited the crystallization of D-mannitol during cooling, and enabled the observation of its glass transition. CONCLUSIONS: Despite their structural dissimilarity, significant melt miscibility exists between D-mannitol and NaCl. Their phase diagram has been determined and features polymorph-dependent eutectic points. NaCl influences the polymorphic behavior of mannitol, and the effect is linked to the crystallization of mannitol in two polymorphic stages.     

Characterization of Glucose Dependent Gel-Sol Phase Transition of the Polymeric Glucose-Concanavalin A Hydrogel System

Purpose. The main goal of this study was to synthesize and characterize hydrogels which undergo reversible gel-sol phase transformation in response to changes in glucose concentration in the surrounding environment. Methods. The glucose-sensitive hydrogels were made by mixing the appropriate concentrations of acrylamide-allyl glucose copolymer and concanavalin A (Con A). To examine their phase reversibility, hydrogels in dialysis membranes were cycled between glucose-free and glucose-containing buffers. The binding affinity of allyl glucose (AG) to Con A was examined by using an equilibrium dialysis technique. Results. The synthesized hydrogels underwent phase transition to sol in the presence of free glucose in the environment. The concentration of external free glucose (C_f) had to be at least 4 times that of polymer-bound glucose (C_p) to induce phase transition from gel to sol. The binding affinity study showed that binding of AG to Con A was four times stronger than that of free glucose. When C_p in the gel was 0.42 mg/ml or higher, C_f had to be much higher than 4 times C_p to induce phase transition. Conclusions. The synthesized hydrogels underwent phase transition in the presence of free glucose in the environment, but the phase transition was not linearly dependent on the concentration of free glucose. This non-linear dependence was explained by the increased binding affinity of AG over native glucose to Con A, and the cooperative interactions between polymer-bound glucose and Con A.     

蒙古族与汉族人群GSTM3及CYP1A1基因多态性的研究

目的研究内蒙古地区蒙、汉族人群GSTM3和CYP1A1 Exon7基因多态性。方法采用聚合酶链式反应-限制性片断长度多态性（PCR-RFLP）和等位基因特异性扩增（ASA）技术分析内蒙古地区412例健康蒙古族人和436例健康汉族人的GSTM3及CYP1A1 Exon7基因多态性及基因型分布频率。结果内蒙古地区蒙、汉族人群GSTM3基因型之间的分布频率具有显著性差异（P〈0.05）,CYP1A1 Exon7基因型分布频率无显著性差异（P〉0.05）。结论 GSTM3基因型频率在内蒙古地区健康蒙、汉族人群中的分布具有显著差异,而CYP1A1 Exon7基因型分布频率无显著性差异。     

On the Polymorphism of Griseofulvin: Identification of Two Additional Polymorphs

In this paper, we present an investigation of the polymorphism of griseofulvin. In addition to the only reported crystalline form (form I), two new polymorphic forms (II and III) have been identified and characterized by differential scanning calorimetry and powder X-ray diffraction. Reasons why these two polymorphs were isolated during the present study, but not detected during the numerous previous studies on this drug, are also discussed.     

GSTT1基因、GSTM1基因多态性与乳腺癌关系的对照研究

目的：探讨女性乳腺癌人群中GSTT1基因、GSTM1基因多态性在乳腺癌发生发展中的作用。为筛选易感人群、早期诊断及有效地预防和治疗措施的建立提供参考依据。方法：采用聚合酶链反应（PCR）、限制性片段长度多态性（RFLP）及琼脂糖凝胶电泳法对105例正常人和100例乳腺癌患者GSTT1基因、GSTM1基因的多态性分布进行检测，Logistic回归等方法估计基因、基因与乳腺癌相关危险因素的交互作用对乳腺癌发病的危险度。结果：GSTT1、GSTM1基因和乳腺癌的危险性呈负相关，OR（95％CI）分别为0．322（0．175～0．593）和0．340（0．188～0．615）；GSTT1基因与GSTM1基因的交互作用和乳腺癌的发病有统计学关联，GSTM1基因和GSTT1基因同时缺失的人群OR（95％CI）为12．338（3．621～22．042）；GSIT1基因及GSTM1基因与多个乳腺癌相关危险因素存在交互作用。结论：GSIT1、GSTM1基因的缺失是乳腺癌发病的危险因素；特定的环境暴露背景下，基因在与环境危险因素的相互作用促进乳腺癌的发生。     

GSTT1基因、GSTM1基因多态性与乳腺癌关系的对照研究

目的：探讨女性乳腺癌人群中GSTT1基因、GSTM1基因多态性在乳腺癌发生发展中的作用。为筛选易感人群、早期诊断及有效地预防和治疗措施的建立提供参考依据。方法：采用聚合酶链反应（PCR）、限制性片段长度多态性（RFLP）及琼脂糖凝胶电泳法对105例正常人和100例乳腺癌患者GSTT1基因、GSTM1基因的多态性分布进行检测，Logistic回归等方法估计基因、基因与乳腺癌相关危险因素的交互作用对乳腺癌发病的危险度。结果：GSTT1、GSTM1基因和乳腺癌的危险性呈负相关，OR（95％CI）分别为0．322（0．175～0．593）和0．340（0．188～0．615）；GSTT1基因与GSTM1基因的交互作用和乳腺癌的发病有统计学关联，GSTM1基因和GSTT1基因同时缺失的人群OR（95％CI）为12．338（3．621～22．042）；GSIT1基因及GSTM1基因与多个乳腺癌相关危险因素存在交互作用。结论：GSIT1、GSTM1基因的缺失是乳腺癌发病的危险因素；特定的环境暴露背景下，基因在与环境危险因素的相互作用促进乳腺癌的发生。     

EPHX1基因多态性与华法林稳定剂量关系的研究

目的:探讨环氧化物水解酶基因(EPHX1)rs4653436(G>A)基因多态性位点与个体间华法林稳定剂量差异的关系。方法:采用聚合酶链反应/变性高效液相色谱技术,检测217例已获得华法林稳定剂量患者的rs4653436(G>A)位点基因型;比较不同基因型患者华法林稳定剂量的差异。结果:217例患者中,基因型GG、GA和AA分别有141、72和4例,各占65.0%、33.2%和1.8%,G和A等位基因的频率分别为81.6%和18.4%。GG、GA和AA基因型患者的华法林稳定剂量分别为(2.84±1.19)、(2.91±1.09)和(2.66±1.29)mg/d,3组之间差异无统计学意义(F=0.155,P=0.856)。结论:EPHX1 rs4653436(G>A)基因多态性可能不是影响华法林个体间用量差异的遗传因素。     

纤溶酶原激活物抑制剂-1启动子基因多态性与静脉血栓栓塞症的相关性研究

目的：探讨中国汉族人群纤溶酶原激活物抑制剂PAI-1启动子4G/5G基因多态性与静脉血栓栓塞症（VTE）发病的相关性。方法：采用病例-对照研究,收集南京鼓楼医院2016年1月～2018年3月VTE患者160例及正常人群160例,应用聚合酶链反应测定PAI-1启动子区域的4G/5G的多态性。结果：PAI-1基因4G/5G三种基因型4G/4G型、4G/5G型、5G/5G型在VTE组的分布频率为42.50%、35.00%、22.50%,对照组分布频率为17.50%、43.12%、39.38%,VTE组与对照组4G/4G基因型分布差异具有统计学意义（P<0.05）;通过非条件Logistic回归模型校正后,PAI-1 4G/4G基因型（OR=3.398,95% CI=2.025～5.702,P=0.000）、吸烟（OR=1.447,95% CI=1.022～2.049,P=0.037）是VTE的独立危险因素。结论：VTE组PAI-1 4G/4G基因型频率较正常人群高,证实了4G/4G基因型与静脉血栓栓塞发病有相关性,且为独立危险因素。     

伊立替康所致不良反应与 UGT1A1*28基因多态性的临床研究

目的：检测恶性肿瘤患者UGT1A1*28基因多态性的分布情况,探讨其与伊立替康所致不良反应的关系。方法对63例恶性肿瘤外周血标本采用PCR扩增和基因测序的方法检测 UGT1A1*28的基因型 TA（6）／TA（6）纯合子、TA（6）／TA（7）杂合子、TA（7）／TA（7）纯合子。结果迟发性腹泻的发生上一般临床特征如患者的年龄、性别、ECOG评分、复发转移灶、合并疾病史、剂量强度差异均无统计学意义（P＞0．05）;而在中性粒细胞减少的发生上,剂量强度是危险因素（P＜0．05）,余各项特征差异无统计学意义（P＞0．05）;TA（6）／TA（6）正常野生型48例（76．19％ ）,TA（6）／TA（7）杂合基因型15例（23．81％ ）,TA（7）／TA（7）纯合突变型0例;基因TA（6）／TA（6）野生型与TA（6）／TA（7）杂合型在患者的性别、年龄、ECOG评分、合并疾病、原发灶的部位与复发转移灶临床特征之间差异均无统计学意义（P＞0．05）。结论 UGT1A1*28基因TA（6）／TA（6）野生型最为常见,TA（6）／TA（7）杂合型次之;迟发性腹泻的发生与剂量强度无明显相关性,UGT1A1*28基因多态性是腹泻危险因素,TA（6）／TA（7）型基因患者迟发性腹泻的发生率增加;中性粒细胞减少的发生与剂量强度呈正相关,剂量强度越大的患者可能越易发生中性粒细胞的减少。     

格列齐特原发失效与SUR1基因多态性的相关性研究

目的：观察天津汉族2型糖尿病患者服用格列齐特后的药物疗效及其与磺脲类受体（SUR）1基因33外显示Ser1369Ala多态性分布的关联性.方法：选择确诊时间＜5年,最近2个月降糖药物治疗时间累计＜1周,且最近1周无任何降糖药治疗史的患者166例.空腹血糖7.8～15.0 mmol/L,体质量指数＜28 kg/m^2.给予格列齐特治疗8周,观察药物疗效.取静脉血提取DNA,Taqman荧光定量PCR法测定SUR1基因33外显子Ser1369Ala的多态性.据单核苷酸碱基多态性分为tt、cc、ct组进行药效的比较.结果：tt组患者空腹胰岛素和HOMA模型B细胞功能指数低于cc、ct组,具有tt基因型和t等位基因的患者药物失效率明显高于具有cc、ct基因型及c等位基因的患者.结论：SUR1基因33外显子Ser1369Ala的多态性与磺脲类药物的原发性失效相关,可能是由于tt基因型影响了SUR1的功能,导致胰岛素分泌减少所致.     

Polymorphism, pseudopolymorphism, and amorphism of peracetylated alpha-, beta-, and gamma-cyclodextrins

Polymorphism, pseudopolymorphism, and amorphism of hexakis(2,3,6-tri-O-acetyl)-alpha-cyclodextrin (TAalphaCyD), heptakis(2,3,6-tri-O-acetyl)-beta-cyclodextrin (TAbetaCyD), and octakis(2,3,6-tri-O-acetyl)-gamma-cyclodextrin (TAgammaCyD) were investigated using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), powder X-ray diffractometry (XRPD), Fourier transform infrared spectroscopy (FTIR) and optical microscopy. An anhydrous and a bi-hydrate crystalline forms of TAalphaCyD, two monotropic anhydrous polymorphs and three pseudopolymorphs (i.e. methanolate, hydrate, and isopropanolate-hydrate) of TAbetaCyD, as well as two monotropic anhydrous polymorphs and isostructural pseudopolymorphs (e.g. hydrate and isopropanolate-hydrate) of TAgammaCyD were isolated and characterized. The amorphous forms of each TACyD were also obtained. Thermal data for desolvation of TAalphaCyD.2H2O and TAbetaCyD.CH3OH were reconciled with their crystal packing features. Melting temperatures and enthalpies of the crystalline forms of each TACyD can be referred to for possible solid-state interactions with drugs.     

The Use of Inverse Phase Gas Chromatography to Study the Glass Transition Temperature of a Powder Surface

PURPOSE: To measure the glass transition temperature (Tg) at the surface of a hydrophobic particle at different temperatures and humidities, on the hypothesis that the surface may be plasticized to a different extent to the bulk due to slow water sorption giving a concentration gradient of water through the particles. METHODS: Amorphous indomethacin was exposed to a range of relative humidities (RH) and temperatures in an inverse gas chromatograph (IGC). The retention volumes of decane were calculated at all conditions using center of mass (Vcom) and peak height (Vmax) methods. The extent of water sorption was determined gravimetrically. RESULTS: The Vcom retention volumes were found to deviate from Vmax results at certain critical humidities at each temperature. This was taken as a novel method for determining the Tg of the sample surface at different experimental conditions. Extrapolating the critical RH to lower the Tg to experimental temperature to 0% RH yeilded a Tg similar to literature values. Water sorption data provided valuable information on changes in mobility of the amorphous form as a function of temperature and RH. CONCLUSIONS: It is possible to use IGC to determine the Tg of the surface of particles at defined conditions. This overcomes the problems of conventional methods of assessing Tg, relating to disruption of water sorption on heating. This helps in the understanding of the physical form of the surface of hydrophobic particles and how and when the surface will start to crystallize.