A retrospective evaluation of furosemide and mannitol for prevention of cisplatin-induced nephrotoxicity.

WHAT IS KNOWN AND OBJECTIVE: Nephrotoxicity is a recognized side effect of cisplatin chemotherapy. However, the optimal strategy for preventing cisplatin-induced nephrotoxicity, if any, remains unclear. The primary objective for this study was to determine whether mannitol or furosemide provides better nephroprotection when administered with hydration prior to weekly, low-dose cisplatin concurrently with whole pelvic radiotherapy. METHODS: Clinical data were abstracted from all women who underwent chemoradiation for FIGO IB2-IVA cervical cancer at a regional safety net health system between January 2009 and December 2014. Creatinine clearance was estimated using the IDMS-traceable MDRD Study Equation. Descriptive statistics were used to summarize patient demographics. Cox proportional hazard models were used to identify factors associated with hypomagnesemia and survival. RESULTS AND DISCUSSION: A total of 133 women received 656 weekly doses of single-agent cisplatin (40 mg/m2 ) concomitant with whole pelvic radiation. Furosemide (20 mg) was administered intravenously prior to 341 cisplatin doses, whereas mannitol (24 g) was administered prior to 315 doses. Significant magnesium wasting was observed after the second weekly cisplatin infusion regardless of whether furosemide or mannitol was utilized. Repetitive low-dose cisplatin infusion had no impact on measured levels of serum creatinine or estimated glomerular filtration rate. Prior history of hypertension, diabetes mellitus, hepatitis C infection and acute gastrointestinal toxicity were each associated with early onset of hypomagnesemia. WHAT IS NEW AND CONCLUSIONS: Repetitive administration of low-dose cisplatin concurrent with whole pelvic radiation is associated with magnesium wasting. However, choice of diuretic with pretreatment hydration had no significant impact on the severity of this adverse effect.

Bovine papillomavirus type 1 infection is mediated by SNARE syntaxin 18.

Events that lead to viral infections include the binding of the virus to the target cells, internalization of the virus into the cells, and the ability of the viral genome to be expressed. These steps are mediated by cellular and viral proteins and are temporally regulated. The papillomavirus capsid consists of two virally encoded capsid proteins, L1 and L2. Much is known about the role of the major capsid protein L1 compared to what is known of the role of the L2 protein. We identified the interaction of the L2 protein with SNARE protein syntaxin 18, which mediates the trafficking of vesicles and their cargo between the endoplasmic reticulum, the cis-Golgi compartment, and possibly the plasma membrane. Mutations of L2 residues 41 to 44 prevented the interaction of L2 protein with syntaxin 18 in cotransfection experiments and resulted in noninfectious pseudovirions. In this paper, we describe that syntaxin 18 colocalizes with infectious bovine papillomavirus type 1 (BPV1) pseudovirions during infection but does not colocalize with the noninfectious BPV1 pseudovirions made with an L2 mutant at residues 41 to 44. We show that an antibody against BPV1 L2 residues 36 to 49 (alpha L2 36-49) binds to in vitro-generated BPV1 pseudoviral capsids and does not coimmunoprecipitate syntaxin 18- and BPV1 L2-transfected proteins. alpha L2 36-49 was able to partially or completely neutralize infection of BPV1 pseudovirions and genuine virions. These results support the dependence of syntaxin 18 during BPV1 infection and the ability to interfere with infection by targeting the L2-syntaxin 18 interaction and further define the infectious route of BPV1 mediated by the L2 protein.