Characterization of Mycobacterium tuberculosis isolated from cancer patients with suspected tuberculosis infection in Egypt: identification,prevalence, risk factors and resistance pattern

Data are sparse on Mycobacterium tuberculosis infection among patients with cancer in Egypt. We sought to detect the presence of tuberculosis (TB) disease among patients with malignant conditions and suspected TB and to study the main risk factors. Also, we compared different diagnostic procedures and detected the antimicrobial susceptibility of M. tuberculosis isolates against rifampin and isoniazid. One hundred patients were included in this study, all of them had malignant conditions and were suspected by the clinicians of having TB. Identification of M. tuberculosis in different specimens was performed by smear microscopy, followed by Lowenstein–Jensen medium and Mycobacterium growth indicator tube (MGIT) cultures and artus^® real-time PCR. In addition, an indirect MGIT anti-TB susceptibility test was carried out against rifampin and isoniazid. A total of 76% of studied cases were found to be TB positive. The frequencies of TB-positive cases in the bronchogenic, haematological and solid tumour malignancy groups were 21%, 25% and 30%, respectively. Significant differences between pulmonary and extrapulmonary TB in different malignancy groups were recorded. Real-time PCR showed the highest overall diagnostic efficiency. Multidrug-resistance of M. tuberculosis to both rifampin and isoniazid was detected in 28.6% of examined isolates. Infection in cancer patients with TB was significantly more often recorded among elderly patients and those suffering from poverty. Pulmonary TB is more common than extrapulmonary TB in patients with malignancy. Real-time PCR is the most accurate and rapid method for TB diagnosis. MGIT-rifampin resistance may be used as a reliable marker for detection of multidrug-resistant TB. Diagnosis and instituting treatment course for active or latent TB infection are crucial before starting anticancer therapy.     

Evaluation of the anticonvulsant activity of 6-(4-chlorophenyoxy)-tetrazolo[5,1-a]phthalazine in various experimental seizure models in mice

This study investigated the anticonvulsant activity of a new phthalazine tetrazole derivative, QUAN-0808 (6-(4-chlorophenoxy)-tetrazolo[5,1-a]phthalazine), in the mouse maximal electroshock (MES) seizure model. The neurotoxicity of QUAN-0808 was investigated using the rotarod neurotoxicity test in mice. QUAN-0808 exhibited higher activity (median effective dose, ED₅₀ = 6.8 mg/ kg) and lower neurotoxicity (median toxic dose, TD₅₀ = 456.4 mg/kg), resulting in a higher protective index (PI = 67.1) compared with carbamazepine (PI = 6.4). In addition, QUAN-0808 exhibited significant oral anticonvulsant activity (ED₅₀ = 24 mg/kg) against MES-induced seizure with low neurotoxicity (TD₅₀ > 4500 mg/kg) in mice, resulting in a PI value of more than 187.5. QUAN-0808 was also tested in chemically induced animal models of seizure (pentylenetetrazole [PTZ], isoniazid [ISO], thiosemicarbazide [THIO] and 3-mercaptopropionic acid [3-MP]) to further investigate the anticonvulsant activity; QUAN-0808 produced significant anticonvulsant activity against seizures induced by ISO, THIO and 3-MP.     

新型在线柱萃取高效液相色谱法测定异烟肼的血药浓度

目的建立新型在线柱萃取HPLC法测定人血浆中异烟肼血药浓度,用于异烟肼的日常治疗药物监测。方法新型在线柱萃取HPLC由萃取系统和分析系统两部分构成。萃取柱为Aston RG SCX（20 mm×4.6 mm,5μm,ANAX）,分析柱为Aston RG C18（250 mm×4.6 mm,5μm）;两系统通过六通阀连接,采用＂中心切割＂模式及陷阱柱转移目标物;检测波长为340 nm,样品经蛋白沉淀、衍生,进样量为50μL,采用外标法计算结果。结果异烟肼在0.18～35.84μg.mL^-1与峰面积呈良好线性关系,相关系数为0.999 8,最低检测限为0.02μg.mL^-1,低（0.18μg.mL^-1）、中（2.24μg.mL^-1）、高（35.84μg.mL^-1）浓度的绝对回收率为91.6%～95.9%,日内和日间RSD均〈5.0%,准确度为98.7%～101.5%。结论本方法具有抗干扰能力强、自动化程度高、准确度和精密度好等优点,完全适合异烟肼的日常治疗药物监测。     

Radiolabeling and evaluation of alginate blend-isoniazid microspheres by 99mTc for the treatment of tuberculosis in rabbit model

Isoniazid (INH) is the first line anti-tubercular drug that is widely used in the treatment of tuberculosis. ^99mTc-alginate-INH microsphere scintigraphy has been demonstrated to be a useful noninvasive imaging technique for microsphere deposits located in different organs of the rabbits. The aim of this study was to develop an improved formulation, to validate the formulation for long-time retention, as well as to assess radiotracer stability by novel quality control methods. Our study reports the labeling and evaluation of alginate blends-INH microspheres. The incorporation efficiency of optimized formulation was 89% w/w. The in vitro release study was carried out in simulated intestinal fluid at pH 7.4, and it was found that the formulation delivered the drug for 36 h. The labeling efficiency of ^99mTc-alginate blends-INH microspheres was seen at various pH (i.e. pH ranging from 5 to 7.5) and different concentration of stannous chloride dehydrate (i.e. 25–200 μg) and it was concluded that 96% labeling efficiency was achieved in case of pH 7.5 and 60 μg stannous chloride. The stability study was carried out in saline and serum and it was found that the complex was highly stable in vitro and in vivo. The blood clearance in rabbits showed bi-exponential pattern depicting that 50% of activity washed out at 2 h with t_1/2(Fast) was 2.1 h and t_1/2(Slow) was 12.5 h. Bio-distribution was normal and the experimental mice showed major accumulation of the radiolabeled formulation in liver, intestine, lungs and kidneys, indicating hepatobiliary and renal route of excretion. The distribution of the drugs to the lung was showing its efficiency in the treatment of tuberculosis.     

Drug-Drug Interaction Studies on First-Line Anti-tuberculosis Drugs

The purpose of this study was to carry out drug-drug compatibility studies on pure first line anti-tuberculosis drugs, viz., rifampicin (R), isoniazid (H), pyrazinamide (Z), and ethambutol hydrochloride (E). Various possible binary, ternary, and quaternary combinations of the four drugs were subjected to accelerated stability test conditions of 40°C and 75% relative humidity (RH) for 3 months. For comparison, parallel studies were also conducted on single drugs. Changes were looked for in the samples drawn after 15, 30, 60, and 90 days of storage. Analyses for R, H, and Z were carried out using a validated HPLC method. The E was analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS), as it does not absorb in ultraviolet (UV). All single pure drugs were relatively stable and showed only 3%–5% degradation under accelerated conditions for 3 months. However, significant interactions were observed in case of the drug mixtures. In particular, ternary and quaternary drug combinations containing R and H along with Z and/or E were very unstable, showing 90%–95% and 70%–75% loss of R and H, respectively. In all these cases, isonicotinyl hydrazone (HYD) of 3-formylrifamycin and H was found to be the major degradation product. In case of RE and RZE mixtures, where H was absent, 3-formylrifamycin was instead the key degradation product. Another unidentified peak was observed in the mixture containing RZE. Apart from these chemical changes, considerable physical changes were also observed in pure E and the mixtures containing E, viz., RE, ZE, RHE, RZE, and RHZE. In addition, significant physical changes associated with noteworthy loss of H and E were also observed in mixtures containing HE and HZE. The present study thus amply shows that the four primary anti-tuberculosis drugs, when present together, interact with each other in a multiple and complex manner.     

A review of antibiotics and psoriasis: induction,exacerbation, and amelioration

ABSTRACT

Introduction: Psoriasis is affected by many environmental factors, including infections and antibiotics. However, the relationship between antibiotics and psoriasis is inadequately studied. Some antibiotics were listed as triggering factors; others showed benefit for psoriasis control. The aim of this article is to review current evidence that may help identify appropriate antibiotics for patients with psoriasis.

Areas covered: The PubMed, Embase, Clinicalkey databases, and google scholar were searched for relevant articles published up to May 2019. Literature regarding antibiotics and psoriasis were included. Six randomized controlled trials and four controlled or cohort studies were identified in 13 kinds of antibiotics.

Expert opinion: Macrolides and rifampin showed decrease of psoriasis area and severity index score in plaque-type psoriasis, while penicillin revealed no statistically significant improvement in guttate psoriasis. Previously tetracyclines were considered as triggering factors, but data were found only in cases or retrospective studies. Mechanisms were thought to be related to immunomodulation rather than bacteria inhibition. Research gap in the influence of genetic susceptibility, the impact on microbiota, and the mode of actions remain to be investigated.     

MDR-TB诊断试剂盒鉴定广东结核分枝杆菌复合群及RIF和INH药敏效果分析

目的评价耐多药结核病(MDR-TB)快速诊断试剂盒对广东地区结核分枝杆菌复合群的鉴定效果及利福平(RIF)和异烟肼(INH)的药敏检测效果。方法选取151份痰标本和150份细菌培养物,采用MDR-TB快速诊断试剂盒对其进行菌群鉴定及RIF和INH药敏检测,结果分别与常规法进行比较。结果与常规生化菌种鉴定结果相比,两者鉴定结果一致率为96.7%(291/301);与常规比例法药敏试验结果相比,诊断试剂盒检测单耐RIF的灵敏度为94.1%(64/68),检测单耐INH的灵敏度为87.7%(57/65),检测RIF和INH皆耐药株的灵敏度为79.3%(46/58),检测RIF和INH皆敏感株的特异性为100%。结论该试剂盒能简单快速地鉴定结核分枝杆菌复合群,检测RIF和INF的敏感性高、特异性好,在广东地区应用前景较好。     

利福平与异烟肼单用及合用对小鼠体内异烟肼代谢及其药代动力学的影响

目的 研究利福平与异烟肼合用对异烟肼及其代谢物乙酰肼、肼药代动力学的影响.方法 分别灌胃给予小鼠异烟肼以及利福平+异烟肼10 d后取血,采用液相色谱-质谱联用法测定异烟肼、乙酰肼和肼的血药浓度.结果 与单用异烟肼相比,合用利福平后乙酰肼的消除速率常数(Ke)显著升高,消除半衰期(t1/2)显著缩短,Cmax以及AUC0...     

Donor‐derived tuberculosis (TB): isoniazid‐resistant TB transmitted from a lung transplant donor with inadequately treated latent infection

Donor‐derived tuberculosis (TB) is an increasingly recognized complication of solid organ transplantation. We report a case of isoniazid‐resistant pulmonary TB in a lung transplant recipient. The patient acquired the infection from the lung donor who was previously empirically treated with isoniazid for latent TB. The case highlights the caveat that, while adequate treatment of latent TB with isoniazid is presumed, meticulous screening of donors is required.