Prognostic impact of RAS mutations in patients with myelodysplastic syndrome

RAS is an oncogene frequently mutated in human cancer. RAS mutations have been reported in 10–15% of cases of acute myeloid leukemia (AML) but they appear to be less frequent among patients with myelodysplastic syndrome (MDS). The impact of RAS mutations in patients with MDS is unclear. We conducted a retrospective study in 1,067 patients with newly diagnosed MDS for whom RAS mutational analysis was available. Overall, 4% of patients carried mutant RAS alleles. Notably, FLT3 mutations, which were found in 2% of patients, were mutually exclusive with RAS mutations. Patients with RAS mutations had a higher white blood cell count as well as bone marrow blasts compared with patients carrying wild‐type RAS. However, no differences were observed between both groups regarding the risk of AML transformation (9% vs. 7%) and overall survival (395 days vs. 500 days, P = 0.057). In summary, RAS mutations are infrequent in patients with MDS and do not appear to negatively impact their outcome. Am. J. Hematol. 88:365–369, 2013. © 2013 Wiley Periodicals, Inc.     

Persistence of hepatitis B vaccine immunity in hemodialysis patients

Although the efficacy of hepatitis B vaccines in patients undergoing chronic hemodialysis (HD) treatment has been documented, the persistence of immunity in this population remains largely unknown. In this study we evaluated the persistence of hepatitis B vaccine immunity in HD patients. We followed 37 hepatitis B vaccinated HD patients (following a four-dose vaccination schedule of 40 mug injections intramuscularly in the deltoid muscle at 0, 1, 2, and 6 months) for up to one year to evaluate the persistence of immunity (as indicated by serum levels of hepatitis B surface antibody (anti-HBs) equal to or higher than 10 IU/L). One year after vaccination, 18.9% of patients had lost their anti-HBs (transient responders), while 81.1% still had detectable antibodies in the serum (persistent responders). From 81.1% of persistent responders 11.5% and 88.5% were weak and high responders, respectively. There was no significant difference between persistent and transient responders regarding age, sex, or nutritional factors. We did not find any factors that related to maintaining protective levels of anti-HBs in HD patients. It seems that an antibody titer above 100 IU/L following vaccination is necessary in order to maintain that level of antibody one year later.     

Chlorhexidine vaginal wipes prior to elective cesarean section: does it reduce infectious morbidity? A randomized trial

Objective: To evaluate the efficacy of preoperative vaginal cleansing using chlorhexidine 0.25% antiseptic wipes on rates of postcesarean section (CS) infectious morbidities (endometritis, febrile morbidity and wound infection).

Methods: This prospective randomized trial was conducted among 218 pregnant women scheduled for term elective CS. Patients were equally divided into two groups by simple randomization. After spinal anesthesia and catheterization under aseptic technique, the study group had preoperative vaginal cleansing using chlorhexidine 0.25% antiseptic wipes for about 1?min, while the control group did not. All cases received the prophylactic antibiotics and the usual abdominal scrub. All participants received the routine postoperative care without other interventions. Adverse postcesarean infectious morbidities such as endometritis, febrile morbidity and wound infection were observed at the time of hospital discharge and weekly for 6 weeks postpartum.

Results: Both groups were matched regarding the baseline patients’ characteristics (age, gestational age, BMI, operative time and postoperative hospital stay). Overall, post-CS infectious morbidity were significantly reduced from 24.4% in the control group to 8.8% in the intervention group; p value?<0.05. Marked reduction was seen in the incidence of endometritis (13.2% in the control group versus 2.9% in the intervention group; p value?<0.05). However, fever and wound infection showed no significant difference between both groups.

Conclusion: Cleansing the birth canal with chlorhexidine 0.25% wipes prior to elective CS appears to be effective in reducing rates of post-CS infectious morbidity mainly endometritis.     

Effect of chronic renal failure on Ca2+ ATPase of brain synaptosomes.

Chronic renal failure (CRF) is associated with a sustained rise in the concentration of cytosolic calcium [( Ca2+]i) of brain synaptosomes. This was attributed to secondary hyperparathyroidism where the excess blood levels of parathyroid hormone (PTH) augment calcium entry into synaptosomes. However, for such an effect of PTH to cause a sustained rise in [Ca2+]i, calcium extrusion out of synaptosomes should be impaired. The study presented here examined the effect of CRF with and without (CRF-PTX) excess PTH and the treatment of CRF rats with verapamil (V) on the Vmax and Km for calcium of synaptosomal Ca2+ ATPase, an enzyme that plays an important role in pumping calcium out of the synaptosomes. The Vmax of synaptosomal Ca2+ ATPase in CRF rats was significantly (P less than 0.01) lower than that of normal, CRF-PTX, CRF-V, and normal-V rats. However, the values in CRF-V were still below normal (P less than 0.05). There were no significant differences in the Km for calcium of synaptosomal Ca2+ ATPase among the five groups of animals. [Ca2+]i was significantly (P less than 0.01) higher in synaptosomes of CRF rats than in normal, CRF-PTX, CRF-V, and normal-V animals, and the values among the latter four groups were not different. The data demonstrate that the activity of synaptosomal Ca2+ ATPase is reduced in CRF rats, and this derangement is related to the excess PTH. This derangement in Ca2+ ATPase activity plays an important role in the genesis of the sustained elevation of synaptosomal [Ca2+]i in CRF.     

The effect of postplacental insertion of the spiked and the standard Lippes loop on uterine involution

The spiked Lippes loop was inserted in 53 women and the standard loop in 55 women immediately following the delivery of the placenta after normal vaginal delivery. A group of 50 recently delivered women with no IUD was studied as a control. The cases were followed up for 1 year. Ultrasonic scanning was performed during the 6th week after insertion for 47 cases with the spiked loop and 43 cases with the standard loop. All loops were correctly positioned within the uterine cavity except in two cases; one using the spiked and the other using the standard loop. The loops were found displaced downwards and as there was excessive bleeding, the devices were removed. Regarding the effect of the IUD on uterine involution, it was found that the fundus to internal os length for the cases with IUDs was shorter than that among the controls, also this length among the standard loop users was significantly shorter than that of the controls (P less than 0.01). Postplacental IUD insertion did not delay uterine involution, on the contrary, it helped involution. Regarding the effect of lactation, the fundus to internal os length for the fully lactating women either using a loop or not, was found to be significantly shorter than that of the non-lactating cases (P less than 0.002).     

Alkylation of urinary guanine in mice by the organophosphorus insecticide tetrachlorvinphos

The methylating capability of tetrachlorvinphos on urinary guanine in mice has been investigated using an insecticide labeled at both O-CH3 groups. Following intraperitoneal administration of the 14C-labeled insecticide to mice, about 0.57% of the radioactivity in the O- to 24-hr samples was associated with the purine fraction. The amount of [7-14C]methylguanine in 0- to 48-hr urine samples, estimated as fraction of applied dose, was 26-31 X 10(-5). The results obtained indicate possible chemical alkylation of urinary guanine. On the other hand, a considerable portion of radioactivity is probably incorporated via the C-1 pool.