Naphthalenesulphonic Acid Derivatives as Potential anti-HIV-1 Agents. Chemistry, Biology and Molecular Modelling of Their Inhibition of Reverse Transcriptase

Activity against human immunodeficiency virus (HIV) in the naphthalenesulphonic acid series is most pronounced in the disulphonic acid series. In this class of compounds, N-acyl derivatives of 4-amino-5-hydroxy-2,7-naphthalenedisulphonic acid demonstrate significant anti-HIV activity at non-toxic doses. The most potent compounds in this group of agents are bis naphthalenedisulphonic acids. A bis derivative containing a decamethylene spacer demonstrated activity against HIV-1, HIV-2 giant cell formation and reverse transcriptase (RT). This compound also demonstrated an in vitro therapeutic index (ratio of 50% cytotoxic concentration to 50% inhibitory antiviral concentration) of 10.6. Molecular modelling analyses of this agent, suramin, and several suramin analogues were undertaken to explain the potent anti-HIV-1 RT activity. These studies were carried out using the molecular decomposition/recomposition strategy, conformational searching, energy minimization and molecular dynamics (MD) simulation. The bis naphthalenedisulphonic acid derivative compound 1, having a flexible decamethylene spacer, was shown to be able to mimic the helical twist of the B-DNA backbone as a low energy conformer state.

Selective Inhibition of Myxovirus Replication by a Novel Series of Cholesterol-Naphthalenesulfonic Acid Hybrid Molecules

A novel series of hybrid molecules with cholesterol and naphthalenesulfonic acid have been synthesized and evaluated for their inhibitory activity against myxoviruses (respiratory syncytial virus [RSV], influenza A and B virus), Naphthalenesulfonic acids (compounds 1–3) and cholesterols (compounds 4 and 5) did not inhibit myxovirus-induced cytopathic-ity. However, hybrid molecules (compounds 6 and 7) proved active against RSV and influenza A virus but not influenza B virus. The antiviral effects of the hybrid compounds 6 and 7 were comparable to those of dextran sulfate. Mixtures of naphthalenesulfonic acid and cholesteryl chloroformate (compounds 1 and 5 molecules, corresponding to the hybrid molecule 6; and compounds 2 and 5, corresponding to the hybrid molecule 7) did not show antiviral activity. The mode of action of the cholesterol-linked naphthalenesulfonic acids can be attributed to inhibition of virus-cell fusion (influenza A virus) or inhibition of both virus-cell binding and fusion (RSV).

Inhibition of HIV-1-Induced Cytopathogenicity, Syncytium Formation, and Virus-Cell Binding by Naphthalenedisulphonic Acids through Interaction with the Viral Envelope gp120 Glycoprotein

Bis-naphthalenedisulphonic acid derivatives with a biphenyl spacer, 4,4′-[4,4′-biphenyldiylbis(sulphonyl-amino)]bis(5-hydroxy-2,7-naphthalenedisulphonic acid) and 3,3′-[4,4′-biphenyldiylbis(sulphonyl-amino)]bis(1,5-naphthalenedisulphonic acid), have previously been reported as potent and selective inhibitors of human immunodeficiency virus type 1 (HIV-1) replication in cell culture. These compounds have also proved inhibitory to syncytium formation in cocultures of MOLT-4 cells with HIV-1-infected HUT-78 cells. They also inhibit the binding of HIV-1 virions to MT-4 cells as determined by a flow cytometric (FACS) method. Further studies on their mechanism of action by the FACS have revealed that the compounds inhibit the binding of anti-gp120 monoclonal antibody to the viral envelope glycoprotein gp120. Binding of OKT4A/Leu3a monoclonal antibody to the cellular CD4 receptor is not affected by the compounds. These results suggest that the anti-HIV-1 activity of the naphthalenedisulphonic acid derivatives can be attributed to inhibition of the gp120-CD4 interaction through binding of the compounds to the viral gp120 antigen.

Bladder cancer in renal allograft recipients: risk factors and outcomes

BACKGROUND

Solid organ transplant recipients have an increased cancer risk owing to immunosuppression and oncogenic viral infections. We report on the incidence and types of bladder cancer in kidney transplant recipients in Ireland, describing possible additional risk factors and outcomes in these patients.

METHODS

We identified kidney transplant recipients diagnosed with de novo bladder cancer between January 1, 1994, and July 31, 2012, by integrating data from the Irish National Cancer Registry and National Renal Transplant Registry. We calculated the standardized incidence ratio (SIR) and examined patient and tumor characteristics and 1-year survival rate.

RESULTS

Fifteen patients were diagnosed with de novo bladder cancer during the study period, representing 0.48% of kidney transplant recipients. The SIR was 2.5 (95% CI, 1.4-4.2; P < .001). The mean interval between transplantation and diagnosis of bladder tumor was 8.6 years and mean age at time of diagnosis was 55.7 years. Sixty percent of patients were male. The tumor types were transitional cell carcinoma (9 patients), squamous cell carcinoma (3 patients), adenocarcinoma (1 patient), carcinoma in situ (1 patient), and diffuse large B-cell lymphoma (1 patient). Beside immunosuppression, risk factors associated with bladder cancer were urogenital disease (6 patients), cyclophosphamide exposure (2 patients), BK nephropathy (1 patient), analgesic nephropathy (1 patient), and extensive smoking (1 patient). Eight patients underwent radical cystectomy for invasive tumors, with resection of other pelvic organs in 7 patients. Mortality rate within the first year was 40%.

CONCLUSION

Bladder cancer occurred more commonly in kidney transplant recipients with a predominance of aggressive tumors and a high mortality. In patients with preexisting risk factors such as urologic abnormalities and cyclophosphamide exposure careful assessment before transplantation and vigilant monitoring posttransplantation with a low threshold for cystoscopy may improve outcomes.

Autosomal Dominant Polycystic Kidney Disease and Intracranial Aneurysms: Is There an Increased Risk of Treatment?

BACKGROUND AND PURPOSE

Autosomal dominant polycystic kidney disease is associated with an increased risk of intracranial aneurysms. Our purpose was to assess whether there is an increased risk during aneurysm coiling and clipping.

MATERIALS AND METHODS

Data were obtained from the National Inpatient Sample (2000-2011). All subjects had an unruptured aneurysm clipped or coiled and were divided into polycystic kidney (n = 189) and control (n = 3555) groups. Primary end points included in-hospital mortality, length of stay, and total hospital charges. Secondary end points included the International Classification of Diseases, Ninth Revision codes for iatrogenic hemorrhage or infarction; intracranial hemorrhage; embolic infarction; and carotid and vertebral artery dissections.

RESULTS

There was a significantly greater incidence of iatrogenic hemorrhage or infarction, embolic infarction, and carotid artery dissection in the patients with polycystic kidney disease compared with the control group after endovascular coiling. There was also a significantly greater incidence of iatrogenic hemorrhage or infarction in the polycystic kidney group after surgical clipping. However, the hospital stay was not longer in the polycystic kidney group, and the total hospital charges were not higher. Additional analysis within the polycystic kidney group revealed a significantly shorter length of stay but similar in-hospital costs when subjects underwent coiling versus clipping.

CONCLUSIONS

Patients with polycystic kidney disease face an increased risk during intracranial aneurysm treatment, whether by coiling or clipping. This risk, however, does not translate into longer hospital stays or increased hospital costs. Despite the additional catheterization-related risks of dissection and embolization, coiling results in shorter hospital stays and similar mortality compared with clipping.

Single centre experience of hypothermic machine perfusion of kidneys from extended criteria deceased heart-beating donors: a comparative study

INTRODUCTION

Kidneys from extended criteria donors are associated with higher rates of delayed graft function (DGF). Hypothermic machine perfusion (MP) for storage is associated with more favourable outcomes.

METHODS

A retrospective analysis was performed in 93 patients where the kidney was stored using hypothermic MP (LifePort(®)) and compared to an age-matched control group where the kidney was stored in cold static storage (CSS) using University of Wisconsin solution.

RESULTS

Median age was similar in both groups (59.2 years in MP vs 59.9 years in CSS, p = 0.5598). Mean cold storage time was 15.6 h in MP vs 17.9 h in CSS. Post transplant mean serum creatinine was as follows; MP group-144.7 μmol/L at 1 month; 138.3 μmol/L at 3 months and 129.5 μmol/L at 12 months. In the CSS group-163 μmol/L at 1 month; 154.9 μmol/L at 3 months and 140.2 μmol/L at 12 months. There was a statistically significant difference at 1 month (p = 0.0096) and 3 months (p = 0.0236). DGF was defined as the need for haemodialysis within 7 days post transplant. In the MP group, DGF occurred in 17.2 % patients with mean of 6 days (range 1-18). In the CSS group, 25.8 % patients with mean of 8.1 days (range 3-25). One-year graft survival rate was better in the MP group (97.85 vs 96.77 %).

CONCLUSION

Our experience to date recommends the use of hypothermic MP for storage of kidneys from extended criteria deceased heart-beating donors.

Electrochemical performance of yttrium substituted LiY(x)Ni(1-x)O2 (0.00 < or = X < or = 0.20) cathode materials for rechargeable lithium-ion batteries

Pristine LiNiO2 and yttrium substituted LiY(x)Ni(1-x)O2 (0.00 < or = X < or = 0.20) cathode materials were synthesized by sol-gel technique using aqueous solutions of metal nitrates and tartaric acid as a chelating agent. Physical properties of synthesized materials were characterized by using X-ray diffraction analysis (XRD), Scanning electron microscopy (SEM) and Transmission electron microscopy (TEM). X-ray powder diffraction analysis showed an increase in lattice parameters with increasing yttrium content yttrium occupies within the layer. SEM and TEM analyses were used to visualize the nature and surface morphological aspects of the oxides. Electrochemical studies were made for the assembled cells using galvanostatic charge/discharge studies discharge rate 0.5 C in the potential range between 3 and 4.5 V. Among them, LiY0.15Ni0.85O2 behaved much better, losing about 5% of its initial capacity (195 mA h g(-1)) after 60 cycles at 185 mA h g(-1). While the pristine LiNiO2 lost about 10% of its initial capacity (164 mA h g(-1)). The substitution of Ni with yttrium, in LiY0.15Ni0.85O2 enhanced the high discharge capacity, good reversibility and best electrochemical performance of rechargeable lithium-ion batteries.

Electrochemical performances of surface modified CePO4-coated LiMn2O4 cathode materials for rechargeable lithium ion batteries

Improved electrochemical performances of Spinel LiMn2O4 cathode was prepared by a sol-gel coating of CePO4 to the surface of the LiMn2O4 powder and subsequent heat treatment at 600 degrees C for 8 h in air. The surface modified LiMn2O4 cathode materials were characterized by using TG/DTA, X-ray diffraction, Scanning electron microscope, X-ray photoelectron spectroscope, cyclic voltammetry techniques and charge/discharge studies. XRD and SEM results show that no significant bulk structural differences are observed between the coated and pristine LiMn2O4. 2 wt.% CePO4 coated LiMn2O4 cathode materials was enhance the particle size compared to pristine due to small layer of CePO4 particle covered on the over the surface. XPS data illustrated that, the CePO4 was completely coated over the surface of the LiMn2O4 core materials. Galvanostatic charge/discharge studies of the uncoated and CePO4-coated LiMn2O4 cathode materials were carried out in the voltage range between 3.0 and 4.5 V at elevated temperature (50 degrees C). The composition of CePO4 coating was increased from 0.0 to 3.0 Wt.%, the initial capacity of the samples decreased slightly. But the cycling stability was increased remarkably between 3-4.5 V. 2.0 Wt.% CePO4-coated LiMn2O4 cathode has satisfied the structural stability, high reversible capacity and excellent electrochemical performances. This result indicates that, the surface treatment should be an effective way to improve the comprehensive properties of the cathode materials for lithium ion batteries.