Evaluation of inhibitory effects of benzothiazole and 3-amino-benzothiazolium derivatives on DNA topoisomerase II by molecular modeling studies

There has been considerable interest in DNA topoisomerases over the last decade, as they have been shown to be one of the major cellular targets in anticancer drug development. Previously we synthesized some benzothiazole derivatives and corresponding benzothiazolium forms, and tested their DNA inhibitory activity to develop novel antitumor agents. Among the 12 prepared compounds, compound BM3 (3-aminobenzothiazole-3-ium 4-methylbenzene sulfonate) exhibited extreme topoisomerase II inhibitory activity compared with the reference drug etoposide. We also tried to determine the DNA and enzyme binding abilities of BM3 and found that BM3 acted on topoisomerase II first at low doses, while it had also showed DNA minor groove binding properties at higher doses. In this study the interactions between DNA topoisomerase II and the compounds were examined in detail by molecular modelling studies such as molecular docking and pharmacophore analysis performed using Discovery Studio 3.5. As a result, it was found that benzothiazolium compounds exhibited a totally different mechanism than benzothiazoles by binding to the different amino acids at the active site of the protein molecule. 3-Aminobenzothiazoliums are worthy of carrying onto anticancer studies; BM3 especially would be a good anticancer candidate for preclinical studies.

Evaluation of the relationship between preeclampsia and seropositivity of infectious disease in maternal plasma

PURPOSE

The aim of the present study was to investigate the association between maternal infections and preeclampsia.

MATERIALS AND METHODS

Fifty-four pregnant women with preeclampsia (study group) and 54 healthy pregnant women (control group) were enrolled in this study. Chlamydia pneumoniae (CP), Mycoplasma hominis (MH), Helicobacter pylori (HP), Cytomegalovirus (CMV), Herpes simplex virus type 2 (HSV-2), and Toxoplasma gondii (TG) antibodies were analyzed in the maternal plasma of all of the participants.

RESULTS

There was no difference in the demographic data between groups. Maternal plasma seropositivity for CP IgM; MH IgA and IgG; HP IgM, IgA and IgG; TG, CMV and HSV-2 IgM and IgG were not significantly different between the preeclampsia and control groups. The seropositivity for CP IgG was significantly higher in women with preeclampsia versus the control women.

CONCLUSIONS

Our results suggested that preeclampsia is associated with CP IgG seropositivity.

Pharmacophore generation of 2-substituted benzothiazoles as AdeABC efflux pump inhibitors in A. baumannii

RND family efflux pumps are important for multidrug resistance in Gram-negative bacteria. To date no efflux pump inhibitors for clinical use have been found, so developing the specific inhibitors of this pump system will be beneficial for the treatment of infections caused by these multidrug-resistant pathogens. A set of BSN-coded 2-substituted benzothiazoles were tested alone and in combination with ciprofloxacin (CIP) against the RND family efflux pump AdeABC overexpressor Acinetobacter baumannii SbMox-2 strain. The results indicated that the BSN compounds did not have antimicrobial activity when tested alone. However, if they were applied in combination with CIP, it was observed that the antibiotic had antimicrobial activity against the tested pathogen, possessing a minimum inhibitory concentration value that could be utilized in clinical treatment. A 3D-common features pharmacophore model was applied by using the HipHop method and the generated pharmacophore hypothesis revealed that the hydrogen bond acceptor property of nitrogen in the thiazole ring and the oxygen of the amide substituted at the second position of the benzothiazole ring system were significant for binding to the target protein. Moreover, three hydrophobic aromatic features were found to be essential for inhibitory activity.

The role of surgical methods in the treatment of anorectal malignant melanoma (AMM)

PURPOSE

Anorectal malignant melanoma (AMM) is a rare tumor with a poor prognosis. The aim of this study was to investigate the clinicopathological characteristics and treatment outcomes in patients with AMM.

METHODS

The study included 21 patients diagnosed with AMM between 2000 and 2010 that were evaluated with regard to age, sex, disease stage, treatment modality, and survival. Stage I, II, and III were defined as localized primary malignant melanoma, regional lymph node metastasis, and distant metastasis, respectively.

RESULTS

In all, 12 (57%) patients were female and 9 (43%) were male ; median age was 61 years (range : 30-84 years). Among the 21 patients, 7 (47%) underwent abdominoperineal resection and 8 (53%) were treated using wide local excision. Four (19%) patients were classified as stage I, 10 (48%) as stage II, and 7 (33%) patients as stage III. In total, 10 patients received adjuvant therapy. Median overall and progression-free survival was 12 and 9 months, respectively. The 1-year and 5-year overall survival estimates were 59% and 42%, and progression free survival were 49% and 7%, respectively. Patients aged > 60 years (P = 0.145), female patients (P = 0.076), patients with localized disease (P = 0.045), patients that underwent wide local excision (P = 0.619), and patients that received adjuvant therapy (P = 0.962) had longer survival.

CONCLUSIONS

The prognosis of AMM remains very poor and disease stage is the only predictor of survival. Abdominoperineal resection does not confer an advantage, in terms of survival, in patients with AMM.

Is there any diagnostic value of serum protease-activated receptor-1 (PAR1) levels on determination of epithelial ovarian carcinoma?

The role of molecular markers in ovarian cancer is still a matter of debate. Protease-activated receptor-1 (PAR1) might be a good marker in some types of malignant tumors and might provide useful information in diagnosis and prognosis. The objective of this study was to evaluate the serum levels of PAR1 in regard to diagnostic, predictive, and prognostic value in epithelial ovarian cancer (EOC) patients. Forty-four EOC patients were enrolled in this study. Serum PAR1 levels were determined by enzyme-linked immunosorbent assay (ELISA) method. Twenty-five age- and sex-matched healthy controls were included in the analysis. The median age of patients was 58 years old, ranging from 22 to 83 years, where most of them had advanced disease (stage III-IV) (n = 40, 91%). The median serum PAR1 values were significantly elevated in patients compared to healthy controls (1.52 ng/ml vs. 1.13 ng/ml) (p = 0.03), whereas any clinical variables including response to chemotherapy did not associate with serum assay (p > 0.05). Progression-free survival (PFS) and overall survival (OS) of patients who did not respond to chemotherapy nor had platinum resistance in relapsed disease were poorer in the analyses. On the other hand, serum PAR1 levels showed no significant adverse effect on either PFS or OS (p = 0.43 and p = 0.49, respectively). These results proved that baseline serum PAR1 levels of patients with EOC were significantly higher than those of healthy people. However, these assays suggested no predictive or prognostic value in this group of patients.

A comparison of the effects of lidocaine or magnesium sulfate on hemodynamic response and QT dispersion related with intubation in patients with hypertension

BACKGROUND

The aim of this study was to investigate the effect of magnesium administered before induction on the hemodynamic response and QT dispersion (QTd) related with intubation in hypertensive patients and to compare it with lidocaine.

METHODS

Patients with essential hypertension who were under ≤ 65 years old, scheduled for elective surgery with a Mallampati score of I-II were included in the study. Patients were randomly divided into three groups; group M (n = 20) received magnesium sulfate, group L was prescribed lidocaine, and group C (control group) received saline. Standard 12-lead ECG readings were taken before the induction of anesthesia and at the first and fifth minutes following intubation.

RESULTS

There were no statistically significant differences between the groups in terms of age, sex and demographic characteristics. There was no significant difference in the QT interval values before induction and 5 minutes after intubation in all groups. In group M, QTd values were significantly lower at the first and fifth minutes than before induction. There were no statistically significant differences in QTd values at different times in group L and group C.

CONCLUSION

QTd is not increased during tracheal intubation in hypertensive patients so there is no need for magnesium sulfate for these patients. But as QTd has been shown to increase during tracheal intubation for coronary artery disease patients, magnesium sulfate might be useful for those patients although future studies are required to confirm this statement.

Dexamethasone added to levobupivacaine in ultrasound-guided tranversus abdominis plain block increased the duration of postoperative analgesia after caesarean section: a randomized, double blind, controlled trial

OBJECTIVES

When added to local anaesthetics, dexamethasone can prolong the duration of peripheral blocks. Dexamethasone has a long and efficient glucocorticoid structure and presents anti-inflammatory properties. The aim of this study was to determine the effect of dexamethasone on the block duration added to levobupivacaine used for transversus abdominis block (TAP) applied to patients who underwent caesarean section.

PATIENTS AND METHODS

Forty-two patients with spinal anaesthesia in an American Society of Anesthesiologists (ASA) I-II risk group were included in the study and divided into two groups. Bilateral 30 ml 0.25% levobupivacaine and 2 ml 0.9% NaCl for the levobupivacaine group and bilateral 30 ml 0.25% levobupivacaine and 2 ml dexamethasone (8 mg) for the dexamethasone group were administered in a TAP block performed with ultrasonography. The time need for the first analgesic in the postoperative period was recorded. The numeric evaluation scale, and the total additional analgesic amounts were recorded.

RESULTS

The time before the administration of the first additional analgesic dose was prolonged significantly in the dexamethasone group compared to the levobupivacaine group (p = 0.004). The pain scores were lower in the dexamethasone group for superficial pain. A significant difference for the dexamethasone group was observed in the evaluation of deep pain. The total consumption of tramadol was significantly lower in the dexamethasone group (p = 0.001).

CONCLUSIONS

The utilization of dexamethasone, which has a prolonging effect on the transversus abdominis plane block, may be an alternative to epidural opioid analgesia in caesarean section. We observed that dexamethasone added to levobupivacaine in a TAP block applied for analgesia following a caesarean section procedure prolonged the time required for analgesia.

Prognostic factors associated with the response to sunitinib in patients with metastatic renal cell carcinoma

OBJECTIVE

We investigated the prognostic clinicopathologic factors associated with overall survival (os) and progression-free survival (pfs) in the once-daily continuous administration of first-line sunitinib in a consecutive cohort of Turkish patients with metastatic renal cell carcinoma (rcc).

METHODS

The study enrolled 77 Turkish patients with metastatic rcc who received sunitinib in a continuous once-daily dosing regimen between April 2006 and April 2011. Univariate analyses were performed using the log-rank test.

RESULTS

Median follow-up was 18.5 months. In univariate analyses, poor pfs and os were associated with 4 of the 5 factors in the Memorial Sloan-Kettering Cancer Center (mskcc) score: Eastern Cooperative Oncology Group performance status of 2 or higher, low hemoglobin, high corrected serum calcium, and high lactate dehydrogenase. In addition to those factors, hypoalbuminemia, more than 2 metastatic sites, liver metastasis, non-clear cell histology, and the presence of sarcomatoid features on pathology were also associated with poor pfs; and male sex, hypoalbuminemia, prior radiotherapy, more than 2 metastatic sites, lung metastasis, nuclear grade of 3 or 4 for the primary tumour, and the presence of sarcomatoid features were also associated with poorer os. The application of the mskcc model distinctly separated the pfs and os curves (p < 0.001).

CONCLUSIONS

Our study identified prognostic factors for pfs and os with the use sunitinib as first-line metastatic rcc therapy and confirmed that the mskcc model still appears to be valid for predicting survival in metastatic rcc in the era of molecular targeted therapy.

Impaired coronary flow reserve in metastatic cancer patients treated with sunitinib

PURPOSE

Hypertension is one of the major side effects of sunitinib, an angiogenesis inhibitor used in the treatment of metastatic renal cell carcinomas (mRCC) and gastrointestinal stromal tumors (GIST). Endothelial dysfunction, an early and reversible event in the pathogenesis of atherosclerosis, is suggested to be one of the possible underlying mechanisms of hypertension caused by angiogenesis inhibitors. Coronary flow reserve (CFR) measurement by trans-thoracic Doppler echocardiography (TTDE) reflects coronary microvascular and endothelial functions, as a cheaper and an easy screening test. We have used TTDE to evaluate endothelial function and coronary microvascular function in mRCC and GIST patients under sunitinib treatment.

METHODS

Eighteen metastatic cancer patients (16 mRCC and 2 GIST) on sunitinib treatment and 27 healthy subjects were enrolled in this cross-sectional study. Thyroid stimulating hormone (TSH), lipid profile, creatinine, hemoglobin, glucose, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), anthropometric and physical parameters of patients were recorded. CFR recordings were performed by the Vivid 7 echocardiography device.

RESULTS

CFR was significantly lower in patients when compared with controls (1.82±0.4 vs 2.71±0.8, respectively; p < 0.001). Impaired CFR was found in 13 (72%) patients whereas all controls had normal CFR values. CFR was inversely correlated with the duration of sunitinib treatment (r=-0.36, p =0.01), high sensitivite (hs) CRP (r = -0.574, p =0.01) and ESR (r = - 0.5, p = 0.02).

CONCLUSION

Our findings indicate that CFR is significantly impaired in cancer patients on sunitinib treatment. There is an inverse correlation between CFR and duration of sunitinib treatment and inflammation markers.

Antiemetic effects of dexamethasone and ondansetron combination during cesarean sections under spinal anaesthesia

BACKGROUND

Nausea and vomiting are frequently seen in patients undergoing cesarean section (CS) under regional anesthesia. We aimed to compare the antiemetic efficacy of ondansetron and dexamethasone combination with that of the use of each agent alone to decrease the incidence of post-delivery intraoperative nausea and vomiting (IONV) during CS under spinal anesthesia.

OBJECTIVE

To compare the antiemetic efficacy of ondansetron and dexamethasone combination with that of the single use of each agent to decrease the incidence of postdelivery IONV during CS under spinal anesthesia.

METHODS

A randomized, prospective, double blind study was performed on 90 patients undergoing planned CS under spinal anesthesia. Patients received 4mg ondansetron in Group O, 8mg dexamethasone in GroupD, 4mg ondansetron+8mg dexamethasone in Group OD intravenously within 1-2 minutes after the umbilical cord was clamped. Frequency of postdelivery IONV episodes was recorded.

RESULTS

A total of 86 eligible patients were included in the study. There were 29 patients in Group O, 29 patients in Group D and 28 patients in Group OD. There were no statistically significant difference between the groups in terms of baseline characteristics and intraoperative managements. Frequency of intraoperative nausea, retching and vomiting experiences were similar between the groups (p>0.05).

CONCLUSION

Single dose 4mg ondansetron, 8mg dexamethasone, or combined use of 8mg dexamethasone+4mg ondansetron, given intravenously is all effective agents for the control of postdelivery IONV. Combined use of dexamethasone and ondansetron for the same indication does not seem to increase the antiemetic efficacy.

Circadian rhythm of serum phosphate, calcium and parathyroid hormone levels in hemodialysis patients

BACKGROUND

Serum levels of Phosphate (P), Calcium (Ca) and Parathyroid hormone (PTH) show circadian rhythms in healthy people. The aim of this study is to investigate whether there is also a rhythm in Hemodialysis (HD) patients.

METHODS

We studied 15 (11 M, 4 F) HD patients, ages were 26 - 70 (mean 53 +/- 15) years. Two of the patients had history of parathyroidectomy operation. Serum levels of phosphate, calcium, albumin and PTH were evaluated six times at 07.00, 11.00, 15.00, 19.00, 23.00 and 03.00 on the second day after scheduled HD session.

RESULTS

The lowest serum phosphate levels were found at 15.00 (5.41 +/- 1.76 mg/dL), the highest levels were 5.97 +/- 1.77 mg/dL at 03.00. The lowest serum Ca levels were 7.90 +/- 1.31 mg/dL at 03.00, the highest levels were 8.39 +/- 1.20 mg/dL at 15.00. Serum levels of PTH increased two times in a day and then decreased. The lowest levels were 330.07 +/- 203.57 pg/mL at 07.00, the highest levels were 418.30 +/- 206.24 pg/mL at 15.00. The results of two patients who had parathyroidectomy history disclosed that the lowest levels of phosphate were 2.87 +/- 0.12 mg/dL at 15.00, the highest levels were 4.37 +/- 1.25 mg/dL at 07.00. Serum Ca levels were as; the lowest levels: 8.29 +/- 3.5 mg/dL at 03.00, the highest levels 9.30 +/- 3.50 mg/dL at 19.00. As expected, serum PTH levels were constantly low during the day disclosing no correlation with other parameters.

CONCLUSIONS

These results show that serum P, Ca and PTH levels exhibit a circadian rhythm also in HD patients. The rhythm predominantly depends on endogen factors and intravascular volume.

Fungal peritonitis in peritoneal dialysis: a 10 year retrospective analysis in a single center

INTRODUCTION

Fungal peritonitis (FP) is a rare but serious complication in patients undergoing peritoneal dialysis (PD), and is associated with higher morbidity, mortality. We aimed to analyze the predisposing factors, etiological agents, outcome and treatment of FP in patients with PD.

METHODOLOGY

We evaluated retrospectively all PD patients PD center between 2001 and 2011. Sixteen patients with FP were included into the study.

RESULTS

The clinical records of 16 patients with FP among 355 patients were reviewed for the clinical and laboratory data. Among 506 episodes of PD-related peritonitis in 10 years, we identified 16 episodes of FP. Median PD duration was 36.7±22.2 months. In 87.5% of patients had one or more previous episode of bacterial peritonitis that were treated with multiple broad-spectrum antibiotics. FP was primary infection in five patients, whereas eleven patients experienced FP during the course of treatment of bacterial peritonitis. Six patients died due to the fungal infection whereas others were transferred to haemodialysis.

CONCLUSIONS

Treatment of bacterial peritonitis with broad spectrum antibiotics was an important risk factor predisposing to the development of FP. The catheter removal and initiation of antifungal therapy as soon as possible are obligatory in episode of FP because it is responsible from high mortality rate.

Magnetic resonance imaging contrast agent related pulmonary edema: a case report

Gadobutrol is a contrast agent often used during magnetic resonance imaging (MRI). The agent has several side effects, some of which can be serious. It has extremely rare life-threatening systemic complications, which can lead to bronchospasm, hypersensitivity reactions and cardiovascular arrest. However, there is no data available on the development of noncardiogenic pulmonary edema following use of gadobutrol. This paper examines the case of a 37-year-old male patient reported to have developed noncardiogenic pulmonary edema after intravenous injection of gadobutrol during MRI.

Insight into eukaryotic topoisomerase II-inhibiting fused heterocyclic compounds in human cancer cell lines by molecular docking

Etoposide is effective as an anti-tumour drug by inhibiting eukaryotic DNA topoisomerase II via establishing a covalent complex with DNA. Unfortunately, its wide therapeutic application is often hindered by multidrug resistance (MDR), low water solubility and toxicity. In our previous study, new derivatives of benzoxazoles, benzimidazoles and related fused heterocyclic compounds, which exhibited significant eukaryotic DNA topoisomerase II inhibitory activity, were synthesized and exhibited better inhibitory activity compared with the drug etoposide itself. To expose the binding interactions between the eukaryotic topoisomerase II and the active heterocyclic compounds, docking studies were performed, using the software Discovery Studio 2.1, based on the crystal structure of the Topo IIA-bound G-segment DNA (PDB ID: 2RGR). The research was conducted on a selected set of 31 fused heterocyclic compounds with variation in structure and activity. The structural analyses indicate coordinate and hydrogen bonding interactions, van der Waals interactions and hydrophobic interactions between ligands and the protein, as Topo IIA-bound G-segment DNA are responsible for the preference of inhibition and potency. Collectively, the results demonstrate that the compounds 1a, 1c, 3b, 3c, 3e and 4a are significant anti-tumour drug candidates that should be further studied.

Contribution of low-molecular weight heparin addition to concomitant chemoradiotherapy in the treatment of glioblastoma multiforme

PURPOSE

Glioblastoma multiforme (GBM) is the most common brain tumor in adults and has a very aggressive course. Median survival is as short as 2 years with standard treatment (chemoradiotherapy followed by adjuvant temozolomide). The purpose of this study was to determine the contribution of low molecular weight heparin (LMWH) addition to concomitant chemoradiotherapy in the treatment of GBM.

METHODS

All patients with newly diagnosed GBM between March 2004-May 2009 were evaluated. After surgical intervention (total, subtotal resection or only biopsy) all of them were treated with concomitant chemoradiotherapy (2 Gy daily, 5 days a week, 30 fractions, total tumor dose 60 Gy; and 75 mg/m² temozolomide, 7 days a week), followed by adjuvant temozolomide (6 cycles, 150-200 mg/m², 5 days every 28 days), with or without LMWH (4000 IU/day, 7 days a week, concomitant with radiotherapy) because of risk of thrombosis. The primary endpoint was the determination of progression-free survival (PFS) and overall survival (OS); secondary endpoints were 1- and 2-year OS survival.

RESULTS

30 patients (13 patients in the group non receiving LMWH (LMWH-) and 17 patients in the group receiving LMWH (LMWH+)) were included in the study. Median age was 54 years (range 24-75). Median PFS was 57 and 38 weeks in LMWH+ and LMWH- groups, respectively (p=0.068). Median OS was 69 and 44 weeks (p=0.095), 1-year OS survival 84.6 and 41.2% (p=0.016), and 2-year OS survival 38.5 and 5.9% in LMWH+ and LMWH-, respectively (p=0.061). No significant difference was noted between the two groups for grade 3-4 toxicity (p>0.05).

CONCLUSION

Better PFS, OS and 2-year OS survival were obtained in present study with the addition of LMWH to concomitant chemoradiation for GBM but without statistical significance. One-year OS survival was statistically significant favoring the LMWH group. The addition of LMWH did not increase temozolomide toxicity.