Pyrimethamine upregulates BNIP3 to interfere SNARE-mediated autophagosome-lysosomal fusion in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common tumor types and remains a major clinical challenge. Increasing evidence has revealed that mitophagy inhibitors can enhance the effect of chemotherapy on HCC. However, few mitophagy inhibitors have been approved for clinical use in humans. Pyrimethamine (Pyr) is used to treat infections caused by protozoan parasites. Recent studies have reported that Pyr may be beneficial in the treatment of various tumors. However, its mechanism of action is still not clearly defined. Here, we found that blocking mitophagy sensitized cells to Pyr-induced apoptosis. Mechanistically, Pyr potently induced the accumulation of autophagosomes by inhibiting autophagosome-lysosome fusion in human HCC cells. In vitro and in vivo studies revealed that Pyr blocked autophagosome-lysosome fusion by upregulating BNIP3 to inhibit synaptosomal-associated protein 29 (SNAP29)-vesicle-associated membrane protein 8 (VAMP8) interaction. Moreover, Pyr acted synergistically with sorafenib (Sora) to induce apoptosis and inhibit HCC proliferation in vitro and in vivo. Pyr enhances the sensitivity of HCC cells to Sora, a common chemotherapeutic, by inhibiting mitophagy. Thus, these results provide new insights into the mechanism of action of Pyr and imply that Pyr could potentially be further developed as a novel mitophagy inhibitor. Notably, Pyr and Sora combination therapy could be a promising treatment for malignant HCC.

Prevalence and Individual-Level Determinants of Uptake of Three or More Doses of Sulphadoxine-Pyrimethamine for Intermittent Preventive Treatment of Malaria in Pregnancy in Busia County, Kenya

Background: Malaria in pregnancy causes maternal anemia, low birth weight, intrauterine growth retardation, and preterm deliveries. In malaria-endemic regions in Kenya, percentage of pregnant women hospitalized with malaria reach up to 60%. WHO recommends at least three doses of sulphadoxine pyrimethamine for Intermittent Preventive Treatment of Malaria in Pregnancy (IPTp) antenatally. This study sought to ascertain the prevalence and individual-level factors influencing the uptake of IPTp-SP3+. Methods: A facility-based cross-sectional study at Busia County Referral Hospital. 384 mothers were consecutively sampled at the maternity unit during delivery. Semi-structured questionnaires were used to collect data. Odds ratio (OR) and adjusted OR were used to determine statistical significance of individual factors influencing uptake of three or more IPTp-SP. Results: 43.0% of participants took IPTp-SP3+. Individual factors that affected the uptake of IPTp-SP3+ included starting ANC visits in the first trimester (adjusted odds ratio (aOR) = 2.1, 95% CI: 1.23 – 3.67, p = 0.046), having more than four ANC visits (aOR = 3.1, 95% CI: 1.49 – 6.50, p = 0.002), having a higher monthly income (aOR = 2.6, 95% CI: 1.24 – 5.36, p = 0.012), being aware of the advantages of IPTp-SP medications (aOR = 3.7, 95% CI: 1.40 – 9.74, p = 0.008), and having a positive attitude toward ANC services (aOR = 3.2, 95% CI: 1.61 – 6.31, p = 0.001). Conclusion: Less than half of the pregnant mothers are complyingIPTp-SP3+. There should be aggressive efforts by the County and National Ministries of Health promoting initiation of ANC attendance early and attendance of all the recommended eight visits together with ensuring availability of the drugs.

Assessment of compliance to sulfadoxine-pyrimethamine 18 months after phasing out chloroquine in Mkuranga District,Coast region-Tanzania

Objective:To observe and assess the compliance to sulfadoxine-pyrimethamine(SP) one and a half years after phasing out chloroquine(CQ) in Mkuranga District,Coast region,Tanzania. Methods:A randomly controlled baseline community study was conducted in rural areas of Mkuranga district,Tanzania.Semi-structured questionnaire consisted of open-and closed -ended questions including home stocking,home use,last fever episodes and treatment of underfives with malaria using CQ or SP.Results:The prevalence of fever or reported fever rate during the last 48 hours by their mothers or guardians was high(70%).Of all 117 blood samples,only 8 children after drug analysis were found to have CQ and 13 had SP concentrations within their blood respectively.None of these blood drug levels were above therapeutic ranges. Conclusions:Community interventions are urgently needed in rural communities and should specifically target households nucleus on early malaria fever recognition and provision of recommended antimalarials for the sick underfive children.However,sadly,there was an increase in underweight and undernourishment in the study areas,probably because of malaria in the area and poverty which are associated with poor nutrition in these youngsters.

Association of Directly Observed Prophylaxis with Sulfadoxine-Pyrimethamine for Prevention of Mother-to-Fetus Transmission of Malaria, Kananga, Democratic Republic of the Congo

Over 90 percent of illness and death attributable to malaria occurs in Sub-Saharan Africa, frequently among pregnant women and young children. Infection with P. falciparum results in high parasitemia percentages and it is the most frequent cause of malaria that results in illness and death in Africa. In areas with holoendemic transmission, such as in most of the Democratic Republic of the Congo (DRC), adults are exposed to malaria every few days or weeks throughout life and, if surviving, have relatively mild bouts of illness because of acquired immunity.

Resistance of <i>Plasmodium falciparum</i>to Sulfadoxine-Pyrimethamine (<i>Dhfr</i>and <i>Dhps</i>) and Artemisinin and Its Derivatives (K13): A Major Challenge for Malaria Elimination in West Africa

The spread of resistance to antimalarials is a major public health problem worldwide and especially in sub-Saharan Africa where the highest morbidity and mortality rates are found with a critical scarcity of data on resistance. The objective of this review is to describe the mutations in the pfdhfr, pfdhps and k13 genes associated with resistance to artemisinin and Sulfadoxine-Pyrimethamine reported in West Africa during the decade 2007 to 2017 followed by a meta-analysis of their prevalence. A bibliographic search on the MEDLINE, PubMed, EMBASE and Sciences Direct databases made it possible to find 405 scientific papers relating to resistance to artemisinin and to Sulfadoxine-Pyrimethamine during the period 2007-2017. The analysis has concerned 217 scientific articles after the elimination of duplicates with 57 articles included in this review after the examination of titles and abstracts. The results of the present review show that the dhfr and dhps mutants are widespread in sub-Saharan Africa. Although, Kelch 13 mutants from Southeast Asia associated with artemisinin resistance are still absent in West Africa, studies have reported the presence of synonymous or non-K13 mutations correlated with a delay in parasite clearance in Burkina Faso (2.26%), Senegal (5.5%) and Togo (1.8%). The increased prevalence of dhfr and dhps mutants in West Africa could jeopardize its use for intermittent preventive treatment in the near future. Despite the absence of strains resistant to artemisinin-based combination therapy in the West African region, increased surveillance is necessary to prevent the rapid occurrence of possible resistance, especially in the context of synonymous or non-K13 mutations correlated with a delay in parasitic clearance.

Comparison of protein patterns between Plasmodium falciparum mutant clone T9/94-M1-1(b3) induced by pyrimethamine and the original parent clone T9/94

Objective:To compare the protein patterns from the extracts of the mutant clone T9/94-M1-1(b3)induced by pyrimethamine,and the original parent clone T9/94 following separation of parasite extracts by two-dimensional electrophoresis(2-DE).Methods:Proteins were solubilized and separated according to their charges and sizes.The separated protein spots were then detected by silver staining and analyzed for protein density by the powerful image analysis software.Results:Differentially expressed protein patterns(up—or down-regulation)were separated from the extracts from the two clones.A total of 223 and 134 protein spots were detected from the extracts of T9/94 and T9/94-M1-1(b3)clones,respectively.Marked reduction in density of protein expression was observed with the extract from the mutant(resistant)clone compared with the parent(sensitive)clone.A total of 25 protein spots showed at least two-fold difference in density,some of which exhibited as high as ten-fold difference.Conclusions:These proteins may be the molecular targets of resistance of Plasmodium falciparum to pyrimethamine.Further study to identify the chemical structures of these proteins by mass spectrometry is required.

Vibrational Spectroscopic Investigations, Electronic Properties, Molecular Structure and Quantum Mechanical Study of an Antifolate Drug: Pyrimethamine

The computational modelling supported by experimental results can explain the molecular structure, vibrational assignments, reactive sites and several structural properties. In this context, the spectroscopic (FT-IR, FT-Raman and NMR) analysis, electronic properties (HOMO and LUMO energies) and molecular structure of pyrimethamine (Pyr) were investigated by density functional theory (DFT) method associated with three levels of theory viz., B3LYP, MN15 and wB97XD with 6-311++G(d,p) and def2TZVPP as basis sets, respectively in the Gaussian 16 programs. The 1H and 13C NMR chemical shifts were calculated with a gauge-independent atomic orbital (GIAO) approach by also applying the same levels of theory and basis sets. All experimental results were compared with theoretical data. Although the results revealed high degrees of correlation between the theoretical and experimental values for spectroscopic properties using the three methods. Furthermore, the atomic and natural charges, energy band gap and chemical reactivity were determined, while the frontier molecular orbital (FMO) and molecular electrostatic potential (MEP) surfaces were plotted to explain the reactive nature of the title molecule.

Effectiveness of non-pyrimethamine-based regimens for toxoplasma encephalitis:A systematic and meta-synthesis study

Objective:To examine the differences in effectiveness and side effects between pyrimethamine-based and non-pyrimethamine-based regimens for toxoplasma encephalitis since the availability of pyrimethamine in Indonesia is currently limited due to its withdrawal from the market.Methods:A systematic review and meta-synthesis study that was carried out by following a protocol guided by the Preffered Reporting Items for Systematic Review and Meta-analysis(PRISMA).Effectiveness measures included clinical improvement,mortality,and radiological improvement.We evaluated selected articles narratively because of the limitations of homogeneity.The risk of bias in RCTs was assessed using the Cochrane Risk of Bias tool for RCT(ROB 2.0)and cohort studies were assessed using the Risk of Bias In Non-Randomized Studies of Interventions(ROBINS-1)tool.Research quality was assessed using the GradePro software.Results:We included two retrospective cohort studies and one RCT.Narrative outcome assessment in these three studies did not show significant difference in effectiveness between pyrimethamine-based and non-pyrimethamine-based regimens for toxoplasma encephalitis treatment.However,drug side effects were consistently higher in the pyrimethamine-based regimen.Conclusions:This study has a high risk of bias.The quality of the research also has a low recommendation value.However,the results may be considered for application if a standard regimen is not available.

HPLC同时测定抗疟复方制剂中磷酸咯萘啶、磺胺多辛与乙胺嘧啶含量

目的 建立同时测定复方抗疟制剂中磷酸咯萘啶、磺胺多辛与乙胺嘧啶的高效液相色谱法.方法 醋酸-醋酸钠（pH6）-乙醇（30：70）为提取溶剂,ZORBAX RX-C18柱（4.6 mm×150mm,5 μm）,[0.022 mol·L^-1盐酸-0.22%三乙胺水溶液（pH 2.3）]-乙腈（75：25）为流动相,流速1 mL·min^-1,非那西丁为内标,266 nm为检测波长.结果 非那西丁、磷酸咯萘啶、乙胺嘧啶与磺胺多辛的保留时间分别为：10.19,1.27,5.70和7.63 min.磷酸咯萘啶、乙胺嘧啶与磺胺多辛的线性范围、相关系数分别为20～400（mg·L^-1）,r=0.999 3;2.05～40.20mg·L^-1,r=0.999 9;20.01～800.40mg·L^-1,r=0.999 9.磷酸咯萘啶、乙胺嘧啶与磺胺多辛的提取回收率和RSD（n=3）分别为（97.62±1.09）%,3.68%;（98.34±1.94）%,1.97%及（99.77±2.16）%,2.17%.结论 本方法灵敏度、准确度均能满足含量测定的需要,提取和测定快速简单,可用于该复方制剂的质量控制.

云南南部恶性疟原虫对甲氟喹、奎宁、氨酚喹、氯喹、磺胺多辛／乙胺嘧啶及咯萘啶敏感性的体外测定

１９９２年１０－１２月在云南南部应用体外微量法测得甲氟喹、奎宁、氨酚喹、氯喹、磺胺多辛／乙胺嘧啶（磺／乙）及咯萘啶对恶性疟原虫的ＩＤ５０依次为４６、４８０、５２、１５０、２×１０４／２５×１０２及１５ｎｍｏｌ／Ｌ；ＩＤ９５分别为１６０、１５３６、２９２、６８０、２４×１０５／３×１０５及６０ｎｍｏｌ／Ｌ。恶性疟原虫对甲氟喹，奎宁均敏感；对氨酚喹及氯喹的抗性率分别为１００％（３０／３０）及９６．７％（２９／３０）；咯萘啶测定５例，其中１例显示有抗性。２０例中有１３例的恶性疟原虫可在最高药量磺／乙井中发育至裂殖体。提示当地恶性疟原虫对氯喹与氨酚喹有明显交叉抗性，对奎宁与甲氟喹可能有交叉抗性。

双氢青蒿素、防2对间日疟和抗药性恶性疟的预防效果

目的 评价双氢青蒿素及防 2对间日疟和抗药性恶性疟的预防效果 ,指导高危人群预防服药。 方法 在云南省边境的勐腊县、景洪市和孟连县发病率≥ 8%的村子 ,随机分成双氢青蒿素 (A、B)组、防 2 (C)组和空白对照(D)组进行预防服药控制疟疾现场研究。 结果 A组带虫率从服药前的 10 40 % ( 5 4/5 91)降到药后的 6 95 % ( 3 7/5 3 3 ) ,下降 3 3 17% ;B组下降 84 70 % ;C组下降 49 82 % ;空白对照组带虫发病率较观察前上升 68 0 0 %。 结论 双氢青蒿素每 15d顿服 6片 ,连续 2月 ,对间日疟和抗药性恶性疟有一定的预防效果 ;防

双氢青蒿素、磺胺多辛乙胺嘧啶联用治疗恶性疟的疗效观察

目的 观察双氢青蒿素与磺胺多辛 乙胺嘧啶联合使用治疗恶性疟的疗效。 方法 以显微镜血检单纯恶性疟原虫阳性患者为观察对象 ,服药后按时测量体温和血检原虫 ,随访 2 8d ,观察治疗效果。结果 收治 36例恶性疟患者 ,全部治愈 ,无 1例复燃 ,治愈率为 10 0 %。平均退热时间为 ( 17.0± 9.9)h ,2 4h原虫下降率为 99.7%± 1.1%,原虫无性体转阴时间平均为 ( 2 6 .2± 9.4)h ,药后无明显不良反应。结论 双氢青蒿素与磺胺多辛 乙胺嘧啶联合使用治疗恶性疟具有良好的效果。

弓形虫感染治疗方法的研究进展

弓形虫病是一种人畜共患寄生虫病,全球有1/3~1/2的人感染该疾病。弓形虫感染的临床表现各不相同,这种差异取决于宿主基因、寄生虫基因、宿主免疫状态、感染量及感染时寄生虫发育状态,这些因素仅是临床症状差异的部分原因。一些急性感染（如在婴儿期和胎儿期感染,大龄儿童、成人或者免疫功能低下者的严重感染）,如治疗及时,可被有效治愈。妊娠期孕妇要进行血清学检测来诊断该病,目的是为了便于在胎儿期和婴儿期进行治疗。一种无毒副作用可以消灭速殖子和缓殖子的药物和一种能防治该疾病的疫苗是全人类未来的共同需要。

氯喹、硝喹、乙胺嘧啶对巨噬细胞释出TNF的影响

目的观测3种抗疟药对疟原虫诱导的大鼠腹腔巨噬细胞释放肿瘤坏死因子（TNF）的影响。方法：以酶联免疫法检测细胞培养液中TNF的含量。结果：感染约氏疟原虫的红细胞可诱导大鼠腹腔巨噬细胞释放TNF，12h时释出量达高锋。氯喹、硝喹明显抑制TNF的释放，乙胺嘧啶作用不明显。结论：氯喹、硝喹抑制TNF释放可能是其抗疟作用机制之一。

扁桃酸对感染小鼠腹水中弓形虫速殖子超微结构的影响

为探讨扁桃酸的杀虫机制 ,应用透射电镜观察扁桃酸对感染弓形虫小鼠治疗 2 4h、72 h和死亡后弓形虫速殖子的超微结构变化 ,扁桃酸 2 0 mg/ m l,0 .2 5 m l/只 ,2次 / d经口灌服和经尾静脉注射途径给药 ,同时用乙胺嘧啶5 mg/ ml,0 .2 5 m l/只 ,1次 / d作为药物对照。结果显示 ,扁桃酸在不同时期对弓形虫的超微结构均有破坏作用 ,且随药物作用时间延长 ,其杀虫作用增强。扁桃酸主要破坏虫体的细胞膜、细胞质中的线粒体、棒状体和内质网等 ,致密颗粒减少或消失。虽然乙胺嘧啶较扁桃酸对虫体的破坏程度稍强 ,但乙胺嘧啶在杀灭虫体的同时也破坏了腹水中正常细胞 ,而扁桃酸对正常细胞几乎无损伤。结果表明 ,扁桃酸的杀虫机制主要是破坏虫体细胞膜、细胞器和染色质 ,从而破坏了虫体赖以生存的理化环境和物质能量的代谢 ,破坏了虫体的遗传物质和遗传信息 ,抑制虫体的增殖。扁桃酸是高效低毒的抗弓形虫药物。

高效液相色谱法测定复方磷酸哌喹片的有关物质

目的建立高效液相色谱法检查复方磷酸哌喹片中有关物质。方法采用Waters Atlantis C18(250 mm×4.6 mm,5μm),以10 mmol.L-1庚烷磺酸钠与25 mmol.L-1磷酸二氢钾等量混合溶液-乙腈-甲醇(53∶16∶31,用磷酸调节pH至2.5)为流动相,流速0.9 mL.min-1,检测波长:348 nm,柱温:40℃。结果磷酸哌喹、磺胺多辛两主成分峰与各杂质峰均能良好分离,磷酸哌喹最低检测限为0.41 ng,磺胺多辛最低检测限为108.24 ng。结论该方法简便、快速,结果准确可靠,适用于复方磷酸哌喹片中有关物质的检查。

抗疟药咯萘啶与磺胺多辛及乙胺嘧啶配伍治疗恶性疟结果的分析

本文对咯萘啶与磺胺多辛和乙胺嘧啶配伍，多年来在海南和云南的抗药性地区治疗恶性疟的结果进行综合分析，认为这种配伍不宜用于抗药性恶性疟地区的防治。因为：（1）未能明显地延缓恶性疟原虫对该种伍用产生抗药性，纵向监测于用药8年后，出现RⅢ病列，药后24h的减虫率明显下降（P＜0．05）；（2）恶性疟治疗后28d，60％左右的病例仍携带配子体，经大劣按蚊和微小按蚊血餐后，在诞腺中可查见子孢子，表明此种配伍治疗后，会引起恶性疟的传播与扩散。

乙胺嘧啶对雄性大鼠抗生育作用的实验研究

目的 :研究乙胺嘧啶的抗生育作用及其可逆性。方法 :通过给SD雄性大鼠灌服不同剂量乙胺嘧啶 5 0d后 ,观察其睾丸和附睾质量及组织学形态、附睾尾部精子活率和畸形率、血清睾酮含量、雄鼠的致孕率变化。结果 :15 0mg·(kg·d) - 1 组变化最明显 ,睾丸质量和脏器系数下降 ,睾丸曲细精管生精细胞排列疏松和结构紊乱 ,附睾上皮细胞肿胀和纤毛脱落 ,致孕率显著下降 ,实验各组附睾尾部精子存活率和畸形率均有下降 ,但血清睾酮含量没有显著变化。结论 :乙胺嘧啶对睾丸生精过程和附睾上皮功能有影响 。

硅胶表面乙胺嘧啶分子印迹聚合物的制备及其性能研究

以表面接枝乙烯基的硅胶作为载体,以甲基丙烯酸为功能单体,乙二醇二甲基丙烯酸酯为交联剂,乙胺嘧啶为模板分子,合成一种具有选择性识别乙胺嘧啶的印迹聚合物。用红外光谱对活化硅胶和烷基化硅胶进行表征,通过静态吸附、Scatchard分析对聚合物的吸附行为进行分析。并对印记效率进行了评价。结果表明,印迹聚合物存在两类不同的结合位点,该印迹聚合物对模板分子具有特异吸附性能,印迹效率为64.24%。

磺胺多辛在半滑舌鳎体内的残留消除规律

在20±2℃水温条件下,以100 mg/kg的剂量,对半滑舌鳎连续口灌3 d,采用超高效液相色谱仪(UPLC)测试磺胺多辛在半滑舌鳎血浆及各组织中的残留浓度,研究磺胺多辛在半滑舌鳎体内的残留消除规律。结果表明,在停药1d后,血浆中的质量浓度最高,在血浆、肌肉、肝脏、肾脏和皮肤中的质量浓度分别为241.5、50.9、16.66、53.15和97.69μg/g;在停药30 d后,磺胺多辛的质量浓度分别为0.30、0.10、0.05、0.08和0.14μg/g。在血浆和各组织中的残留消除方程分别为C血浆=205.8e-0.21t、C肌肉=56.44e-0.21t、C肝脏=19.94e-0.22t、C肾脏=56.86e-0.23t、C皮肤=117.5e-0.23t。中国农业部NY 5070—2002《无公害食品水产品中渔药残留限量》规定的磺胺药的残留限量低于0.1 mg/kg,若低于此限量值,则半滑舌鳎的血浆、肌肉、肝脏、肾脏和皮肤则分别需要36.3、30.2、24.1、27.6和30.7 d。因肌肉和皮肤是可食性组织,且考虑血浆的影响,最终确定在本实验条件下,磺胺多辛在半滑舌鳎体内的休药期不低于37 d。