麦迪霉素临床疗效观察

麦迪霉素是中国医学科学院药物研究所和四川抗菌素工业研究所于1974年各自筛选到的两株链霉菌产生的一种新的大环内酯类抗菌素,由苏州第二制药厂、四川制药厂和上海第四制药厂协作试制,于1977年5月在苏州通过技术鉴定。经研究证明,麦迪霉素与国外近年发表的Medecamycin为同一物质。麦迪霉素对金黄色葡萄球菌、链球菌、肺炎双球菌和白喉杆菌等固紫染色阳性细菌有明显的抗菌作用,对部分耐红霉素的金黄色葡萄球菌有抑制作用。与红霉素不同,它是一种非诱导     

提高麦迪霉素片剂溶出度的研究

麦迪霉素为大环内脂类抗菌素,对革兰氏阳性菌和支原体显示很强的抗菌作用,主要用于金黄色葡萄球菌,溶血性链球菌,肺炎球菌等所致的呼吸道感染及皮肤,软组织感染,也可用于支原体肺炎,是临床常用的抗菌素之一。但市售的麦迪霉素常发现溶出度不合格的现象,对此我们进行了麦迪霉素的溶出度实验研究。     

克拉霉素胶囊的体外抗菌作用试验研究

用体内试验方法对克拉霉素胶囊的抗菌活性进行评价，并与红霉素进行比较。对４种７株致病菌感染小鼠的体内抗菌试验结果显示，克拉霉素金黄色葡萄球菌，化脓性链球菌和肺炎双球菌敏感菌的体内保护作用是红霉素６．８１￣８．６２倍，对耐金黄色葡萄球菌和嗜血流感杆菌的体内作用分别优于红霉素１７．９２倍和１７倍。     

克拉霉素胶囊的体内抗菌作用试验研究

用体内试验方法对克拉霉素胶囊的抗菌活性进行评价，并与红霉素进行比较。对4种7株致病菌感染小鼠的体内抗菌试验结果显示，克拉霉素对金黄色葡萄球菌，化脓性链球菌和肺炎双球菌敏感菌的体内保护作用是红霉素6．81～8．62倍，对耐金黄色葡萄球菌和嗜血流感杆菌的体内作用分别优于红霉素17．92倍和17倍。     

千金妇炎舒的抗菌实验研究

目的研究千金妇炎舒在体内和体外实验中的抗菌作用。方法①体外培养大肠埃希菌、金黄色葡萄球菌、枯草芽孢杆菌、肺炎链球菌、嗜血杆菌、甲型溶血性链球菌、乙型溶血性链球菌、淋球菌等标准菌株和不动杆菌、大肠埃希菌、金黄色葡萄球菌、肺炎克雷伯杆菌、表皮葡萄球菌、乙型溶血性链球菌、洋葱假单孢杆菌、枸橼酸肠杆菌、肺炎双球菌等临床分离菌株,观察千金妇炎舒的体外抗菌作用;②体内实验观察了千金妇炎舒对金黄色葡萄球菌和大肠埃希菌对小鼠的保护作用。结果千金妇炎舒体外给药对上述细菌均有抑制作用,其中对金黄色葡萄球菌、甲型溶血性链球菌、乙型溶血性链球菌、表皮葡萄球菌、洋葱假单孢杆菌抑制作用较强,其最小抑菌浓度（MIC）在12.5～50mg/ml。千金妇炎舒体内给药对金黄色葡萄球菌和大肠埃希菌所致感染的小鼠具有保护作用,能降低感染小鼠的死亡率。结论千金妇炎舒具有较明显的抗菌作用。     

青霉素V钾片

【作用特点】本品抗菌谱和青霉素G相同,主要对青霉素G敏感的革兰氏阳性菌如葡萄球菌、链球菌、肺炎双球菌等所引起的感染包括急性感染有明显的作用,并对耐药金黄色葡萄球菌比青霉素G有效。     

2015—2018年黄石市中心医院不同年龄段儿童下呼吸道感染病原菌的分布及耐药性分析

目的 探讨和分析黄石市中心医院不同年龄段儿童下呼吸道感染病原菌的分布及耐药性,指导临床合理选择抗菌药物。方法 对2015年1月—2018年5月黄石市中心医院儿科住院患者下呼吸道分泌物标本进行细菌培养、非典病原体和病毒检测,并采用纸片扩散法对细菌进行药敏监测。结果 共分离出1 298株病原菌,其中革兰阳性菌377株,占29.04%,主要为肺炎链球菌、金黄色葡萄球菌;革兰阴性菌485株,占37.36%,主要为肺炎克雷伯杆菌、流感嗜血杆菌;非典型病原体246株,占18.95%,主要为肺炎支原体;病毒190株,占14.64%。0～3岁组的革兰阳性菌、病毒和非典型病原体分离率显著小于3～7岁组和>7岁组,差异具有统计学意义（P<0.05）,而0～3岁组的革兰阴性菌分离率显著大于3～7岁组和>7岁组,差异具有统计学意义（P<0.05）。药敏结果显示肺炎链球菌对氨苄西林舒巴坦、头孢唑林、克林霉素、阿奇霉素的耐药率较高,肺炎克雷伯杆菌对氨苄西林舒巴坦、头孢呋辛、头孢噻肟、氨曲南、妥布霉素等耐药率较高。0～3岁组肺炎链球菌和肺炎克雷伯杆菌等对常见抗菌药物的耐药率大于3～7岁组和>7岁组。结论 黄石市中心医院不同年龄的感染率和细菌耐药率存在明显差异,临床应根据不同年龄段患儿病原菌分布特点及耐药趋势,合理选择抗菌药物。     

头孢菌素类与大环内酯类抗菌药物联用对下呼吸道感染患者的疗效及其对病原菌的敏感性分析

目的:分析头孢菌素类与大环内酯类抗菌药物联用对下呼吸道感染患者的疗效及其对病原菌的敏感性。方法:选取2017年5月—2018年5月期间收治的下呼吸道感染患者96例资料,按治疗方式的不同将其分为观察组与对照组(每组48例);对照组患者给予红霉素胶囊与复方甘草合剂联用治疗,观察组患者在对照组基础上加用第2代头孢菌素类抗菌药物如头孢克洛胶囊治疗,比较两组患者治疗后的总有效率,以及不同病原菌对大环内酯类抗菌药物的耐药率差异。结果:观察组患者治疗后的总有效率为97.92%明显高于对照组为83.33%(P<0.05);两组患者感染病原菌的分布与构成比经组间比较其差异无统计学意义(P>0.05);金黄色葡萄球菌、表皮葡萄球菌对3种大环内酯类抗菌药物的耐药率由低到高依序为阿奇霉素<罗红霉素<红霉素;肺炎链球菌对阿奇霉素、罗红霉素的耐药率均为38.46%低于红霉素为46.15%,对阿奇霉素、罗红霉素和红霉素的耐药率由低到高依序为表皮葡萄球菌<金黄色葡萄球菌<肺炎链球菌。结论:下呼吸道感染患者感染病原菌主要为大肠埃希菌、肺炎克雷伯菌、金黄色葡萄球菌和鲍曼不动杆菌等;金黄色葡萄球菌、表皮葡萄球菌和肺炎链球菌对阿奇霉素的耐药率较低;而头孢菌素类与大环内酯类抗菌药物联用治疗下呼吸道感染患者的疗效较为确切,临床治疗应根据病原菌的分布及其耐药情况合理选用抗菌药物。     

阿奇霉素衍生物的合成和抗菌活性研究.Ⅳ.4"-取代杂芳环亚甲基肼基甲酸酯

以阿奇霉素11,12-环硼酸酯为原料,设计并合成了13个阿奇霉素4"-取代杂芳环亚甲基肼基甲酸酯及4"-取代杂芳环亚甲基肼基甲酸酯-11,12-环碳酸酯衍生物.体外抗菌活性试验结果表明,目标化合物对金黄色葡萄球菌、表皮葡萄球菌、白色葡萄球菌、肺炎双球菌和丙型链球菌等革兰阳性菌,以及福氏志贺菌等革兰阴性菌抗菌活性良好.     

阿奇霉素4″-取代亚苄肼基甲酸酯衍生物的合成和抗菌活性

以阿奇霉素11，12-环硼酸酯为原料．设计并合成了18个阿奇霉素4″-取代亚苄肼基甲酸酯及4″-取代亚苄肼基甲酸酯．11，12-环碳酸酯衍生物。体外抗菌活性试验结果表明，所得化合物对受试革兰阳性菌如金黄色葡萄球菌、表皮葡萄球菌、白色葡萄球菌和肺炎双球菌抗菌活性良好，部分化合物对丙型链球菌、革兰阴性菌如鲍氏志贺氏菌和普通变形杆菌也有较强的抗菌活性。     

Antibacterial and modulatory effect of Stryphnodendron rotundifolium

Context: Stryphnodendron rotundifolium Mart. (Leguminosae), a tree in Northeast Brazil (Chapada do Araripe), is used in popular medicine to treat different processes such as inflammation and infectious diseases, mainly caused by bacterial pathogens.

Objective: This study determined the modulatory and antimicrobial activity of the hydroethanol extract of dried stem bark, the most used form of this natural product, as a remedy by the traditional communities, against standard and clinical isolates of Escherichia coli and Staphylococcus aureus.

Material and methods: The antibacterial and modulatory activities of the hydroalcoholic extract from the leaves were obtained by maceration/hydrodistillation method and assayed by microdilution.

Results: In the microbiological assays, growth inhibition was demonstrated by this extract against the bacterial strains tested, with minimal inhibitory concentration (MIC) values of 512 µg/mL. However, when a subinhibitory concentration (MIC/8?=?64 µg/mL) was combined with conventional antimicrobial drugs (gentamicin, kanamycin, amikacin and neomycin), the extract showed a potentiating effect, reducing the MIC for all drugs assayed in a range between 312.5 and 2.4 µg/mL.

Conclusions: We indicate that the extract of S. rotundifolium showed potential synergistic antibiotic activity. With the results obtained, these extracts proved to be a promising source of antibacterial and modulatory agents.     

Investigation of the antibacterial and antifungal activity of thiolated naphthoquinones

The WHO has stated that antibiotic resistance is escalating to perilously high levels globally and that traditional therapies of antimicrobial drugs are futile against infections caused by resistant microorganisms. Novel antimicrobial drugs are therefore required. We report in this study on the inhibitory activity of the 1,4-naphthoquinone-2,3-bis-sulfides and 1,4-naphthoquinone sulfides against two bacteria and a fungus to determine their antimicrobial properties. The 1,4-naphthoquinone sulfides have potent activity with a minimum inhibitory concentration (MIC) of 7.8 μg/mL against Staphylococcus aureus (Gram +ve), an MIC of 23.4 μg/mL against the fungus, Candida albicans, which was better than that of Amphotericin B (MIC = 31.3 μg/mL), and against Escherichia coli (Gram −ve) an MIC of 31.3 μg/mL was obtained. The 1,4-naphthoquinone had an MIC of 11.7 μg/mL against S. aureus and the 1,4-naphthohydroquinone also had the same activity against E. coli.

In vitro activity of polymyxins in combination with β-lactams against clinical strains of Pseudomonas aeruginosa

The emergence of multidrug-resistant (MDR) strains has made it difficult to treat infections caused by Pseudomonas aeruginosa. In order to develop new alternative therapies for the treatment of MDR P. aeruginosa infections, the antimicrobial activities of different antibiotic combinations have been studied in vitro and in vivo. In this study, the in vitro antimicrobial activities of six different combinations of polymyxins and β-lactams against 34 clinical isolates of P. aeruginosa were evaluated. For the combinations tested by the checkerboard method, an indifferent effect was observed for all strains. However, 27 strains (19 MDR) showed reductions in their minimal inhibitory concentration (MIC) for at least one of the antibiotics in the combinations evaluated. Combination with polymyxins resulted in reductions of the β-lactam MICs, with a change in the resistance category to susceptible in eight MDR strains. These results from the in vitro evaluation suggest that combinations of polymyxins and β-lactams may significantly reduce the MICs of the antibiotics tested. These combinations require further evaluation for use in medical practice.     

Chemical composition and biological activities of Eruca vesicaria subsp. longirostris essential oils

Context To date, there are no reports to validate the Tunisian traditional and folklore claims of Eruca vesicaria (L) Cav. subsp. longirostris (Brassicaceae) for the treatment of disease.

Objective Investigation of the chemical composition antimicrobial and antioxidant activity of essential oils from Eruca longirostris leaves, stems, roots and fruits.

Materials and methods The essential oils of E. longirostris from leaves, stems, roots and fruits were obtained after 4?h of hydrodistillation. Chemical compositions were determined using a combination of GC/FID and GC/MS. The in vitro antimicrobial activity of the volatile constituents of E. longirostris was performed in sterile 96-well microplates against three Gram-positive, four Gram-negative bacteria and one strain as yeast. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration values were reported. Furthermore, the antioxidant activity was evaluated by DPPH and ABTS assays.

Results The main compound for fruits, stems and roots was the erucin (96.6%, 85.3% and 83.7%, respectively), while β-elemene (35.7%), hexahydrofarnesylacetone (23.9%), (E)-β-damascone (15.4%), erucin (10.6%) and α-longipinene (9.6%) constituted the major compounds in the essential oil of the leaves. The experimental results showed that in all tests, essential oil of fruits showed the better antioxidant activity than the others. On the other hand, the oils of stems, fruits and roots showed significant antimicrobial activity with MIC values ranging from 0.125 to 0.31?mg/mL against Candida species, Gram-positive and Gram-negative bacteria, mainly Salmonella enterica.

Conclusions The present results indicate that essential oils of E. longirostris can be used as a source of erucin.     

Solution structure of a cathelicidin‐derived antimicrobial peptide,CRAMP as determined by NMR spectroscopy

Abstract: CRAMP was identified from a cDNA clone derived from mouse femoral marrow cells as a member of cathelicidin‐derived antimicrobial peptides. This peptide shows potent antimicrobial activity against gram‐positive and gram‐negative bacteria but no hemolytic activity against human erythrocytes. CRAMP was known to cause rapid permeabilization of the inner membrane of Escherichia coli. In this study, the structure of CRAMP in TFE/H₂O (1 : 1, v/v) solution was determined by CD and NMR spectroscopy. CD spectra showed that CRAMP adopts a mainly α‐helical conformation in TFE/H₂O solution, DPC micelles, SDS micelles and liposomes, whereas it has a random structure in aqueous solution. The tertiary structure of CRAMP in TFE/H₂O (1 : 1, v/v), as determined by NMR spectroscopy, consists of two amphipathic α‐helices from Leu⁴ to Lys¹⁰ and from Gly¹⁶ to Leu³³. These two helices are connected by a flexible region from Gly¹¹ to Gly¹⁶. Previous analysis of series of fragments composed of various portion of CRAMP revealed that an 18‐residue fragment with the sequence from Gly¹⁶ to Leu³³ was found to retain antibacterial activity. Therefore, the amphipathic α‐helical region from Gly¹⁶ to Leu³³ of CRAMP plays important roles in spanning the lipid bilayers as well as its antibiotic activity. Based on this structure, novel antibiotic peptides having strong antibiotic activity, with no hemolytic effect will be developed.     

Excipient Interaction with Cetylpyridinium Chloride Activity in Tablet Based Lozenges

Purpose. The purpose of the investigation was to determine the effect of tablet excipients on the activity of cetylpyridinium chloride (CPC) and the relative interaction between excipients and CPC. Methods. An analytical assay was developed to evaluate the interaction between CPC and the excipients. In vivo activity was investigated using six volunteers by determining the reduction in colony forming units recoverable from the oropharynx after sucking each proprietary lozenge separately on different days. In vitro determinations investigated the relative antimicrobial activity of aqueous solutions of the lozenges and, the effect of pH and tablet base excipients on that activity against Staphylococcus aureus, Streptococcus pyogenes and Candida albicans. Results. Both in vivo and in vitro results showed that the tablet based lozenges had markedly reduced antimicrobial activities compared with previous results with a candy based lozenge (in vivo and in vitro) or the same concentration of aqueous CPC (in vitro}. Magnesium stearate suspensions in CPC 250 µg/ml indicated that magnesium stearate adsorbed CPC and at 0.4% lozenge weight and above significantly reduced the antimicrobial activity of CPC 250 µg/ml. Conclusions. The reduced activity of CPC in tablet based lozenges resulted from a decreased availability of CPC in solution due to an adsorption of CPC on magnesium stearate. To avoid this reduction in activity tablet based lozenges containing CPC 250 µg/ml, or similar concentrations, plus magnesium stearate should contain not more than 0.3% w/w lozenge weight of the lubricant.     

Antimicrobial peptides from the skin of the Japanese mountain brown frog,Rana ornativentris

Abstract: Six peptides with antimicrobial activity were isolated from an extract of freeze‐dried skin of the Japanese mountain brown frog Rana ornativentris. Two structurally related peptides (brevinin‐20a GLFNVFKGALKTAGKHVAGSLLNQLKCKVSGGC, 11 nmol/g dried tissue, and brevinin‐20b GIFNVFKGALKTAGKHVAGSLLNQLKCKVSGEC, 170 nmol/g) belong to the brevinin‐2 family, previously identified in Asian and European, but not North American, Ranid frogs. Four peptides (temporin‐1Oa FLPLLASLFSRLL.NH₂, 13 nmol/g; temporin‐1Ob FLPLIGKILGTI L.NH₂, 350 nmol/g; temporin‐1Oc FLPLLASLFSRLF.NH₂, 14 nmol/g; and temporin‐1Od FLPLLASLFSGLF.NH₂, 8 nmol/g) are members of the temporin family first identified in the European common frog Rana temporaria but also found in the skins of North American Ranids. The brevinin‐2 peptides showed broad‐spectrum activity against the gram‐positive bacterium, Staphylococcus aureus, the gram‐negative bacterium, Escherichia coli and the yeast Candida albicans, whereas the temporins showed potent activity only against S. aureus. The brevinins and temporins belong to the class of cationic antimicrobial peptides that adopt an amphipathic α‐helical conformation but it is significant that temporin‐1Od, which lacks a basic amino acid residue, is still active against S. aureus (minimum inhibitory concentration=13 µm compared with 2 µm for temporin‐1Oa). This suggests that strong electrostatic interaction between the peptide and the negatively charged phospholipids of the cell membrane is not an absolute prerequisite for antimicrobial activity.     

Antimicrobial Peptides Derived from Fusion Peptides of Influenza A Viruses,a Promising Approach to Designing Potent Antimicrobial Agents

The emergence and dissemination of antibiotic‐resistant bacterial pathogens have spurred the urgent need to develop novel antimicrobial agents with different mode of action. In this respect, we turned several fusogenic peptides (FPs) derived from the hemagglutinin glycoproteins (HAs) of IAV into potent antibacterials by replacing the negatively or neutrally charged residues of FPs with positively charged lysines. Their antibacterial activities were evaluated by testing the MICs against a panel of bacterial strains including S. aureus, S. mutans, P. aeruginosa, and E. coli. The results showed that peptides HA‐FP‐1, HA‐FP‐2‐1, and HA‐FP‐3‐1 were effective against both Gram‐positive and Gram‐negative bacteria with MICs ranging from 1.9 to 16.0 μm , while the toxicities toward mammalian cells were low. In addition, the mode of action and the secondary structure of these peptides were also discussed. These data not only provide several potent peptides displaying promising potential in development as broad antimicrobial agents, but also present a useful strategy in designing new antimicrobial agents.     

In vitro evaluation of the antibacterial activity of extracts from 34 species of North American lichens

Context: The emergence of antibiotic resistant pathogens is a serious global health threat. Hence, the search for new antibiotic drugs from various natural sources should be given high priority. Lichens produce a variety of low molecular weight metabolic compounds and many cultures have utilized these compounds in traditional medicine for centuries.

Objective: Report the antibiotic properties of extracts from 34 North American lichens screened against four pathogenic bacteria.

Materials and methods: The micro-well dilution method was used to determine the minimum inhibitory concentration (MIC) of acetone and methanol extracts of 34 lichen species against four bacterial strains. Major chemical compounds in each species were identified using thin layer chromatography (TLC).

Results: Most of the lichen extracts demonstrated inhibitory effects against Staphylococcus aureus, Pseudomonas aeruginosa, and methicillin-resistant S. aureus (MRSA) with MIC values ranging from 3.9 to 500?µg/ml. In addition, extracts from three species, Letharia columbiana (Nutt.) J. W. Thomson (Parmeliaceae), Letharia vulpina (L.) Hue (Parmeliaceae), and Vulpicida canadensis (Räsänen) J.-E. Mattsson &; M. J. Lai (Parmeliaceae) (MIC?=?125–500?µg/ml) were also effective against Escherichia coli. Generally, acetone extractions were found to be more effective than methanol extractions.

Discussion and conclusion: Results of this study show that lichen extracts provide significant antimicrobial activity against both Gram-positive and Gram-negative bacteria. These results suggest that lichens may be an important potential source of antibacterial drugs.     

Green synthesis and characterization of Solanum xanthocarpum capped silver nanoparticles and its antimicrobial effect on multidrug-resistant bacterial (MDR) isolates

Plant extracts and their bioactive compounds are considered as the promising options for green synthesis of nanoparticles instead expensive and hazardous materials. Here, Solanum xanthocarpum fruit was used for synthesis of silver nanoparticles (AgNP). The synthesized AgNPs were characterized by using chromatographic and spectroscopic analytical methods. AgNPs were confirmed by UV-visible absorbance at 420–470 nm. TEM analysis showed AgNP with 22.45 nm average size. X-ray diffraction studies revealed the crystalline and face central cubic nature of AgNPs. FTIR analysis revealed functional group present over AgNPs. The aminodiphenyl acetic acid, clomipramine, and fonisopril from fruit extracts were found to be major capping agents on AgNPs as a result of analysis by HRLC-MS. All clinical isolates showed resistance for ampicilline, amoxyclav, niladixic acid, and sulphafurazole, suggesting multidrug resistance. The results showed that all isolates were sensitive to AgNPs synthesized fruit extracts. On the contrary, all isolates were resistant to whole S. xanthocarpum fruit extracts alone. The antimicrobial activity of AgNP was explored against multidrug-resistant (MDR) Gram-negative clinical isolates including Escherichia coli, Shigella spp., Aeronomonas spp. and Pseudomonas spp. MIC values ranged between 1.25 mg/ml and 2.5 mg/ml at 8 McFarland's standards. Minimum bactericidal concentration was found to be in between 2.5 mg/ml to 5 mg/ml. Nanoparticles synthesized from fruit extract of S. xanthocarpum containing aminodiphenyl acetic acid, clomipramine, and fonisopril metabolites exhibit promising antimicrobial activity against MDR Gram-negative clinical isolates.