Flavobione and thioctacide diminish latent radiation-induced damage to the rat liver

Department of Cellular and Molecular Biology, Natural Science Faculty, P. J. afarik University, Koice, Czechoslovakia. (Presented by Academician of the Academy of Medical Sciences S. E. Severin.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 113, No. 5, pp. 547–549, May. 1992.     

Effect of hepatoprotective agents thioctacid and flavobion on histones in the intact and regenerating liver of irradiated rats

Department of Cellular and Molecular Biology, Faculty of Science, P. J. afarik University, Koice, Czechoslovakia. (Presented by Academician of the Academy of Medical Sciences of the USSR S. E. Severin.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 113, No. 2, pp. 191–193, February, 1992.     

GPMVs in variable physiological conditions: could they be used for therapy delivery?

Background

Cell based carriers are increasingly recognized as a good system for cargo delivery to cells. One of the reasons is their biocompatibility and low toxicity compared to artificial systems. Giant plasma membrane vesicles (GPMV) derive from the cell plasma membrane. Thus they offer the closest approximation to it, which makes them good candidates for potential drug delivery systems. To evaluate the applicability of GPMVs as carriers, we analyzed their basic biophysical properties to test their robustness in the face of changeable physiological conditions, as well as their ability to translocate across the membrane into cells.

Results

GPMVs formed from human umbilical vein endothelial cells (HUVEC) sustain a drastic osmotic challenge (50–500 mOsmoL/kg) unlike giant unilamelar vesicles (GUVs). In hyper-osmotic solutions the average volume decreases and membrane invaginations form, while in the hypo-osmolar buffer the volume of GPMVs increases and these changes were not reversible. The membranes of flaccid GPMVs started to wrinkle unevenly giving rise to buds after exposure to lipopolysaccharide (LPS). The shape changes in GUVs are reversible in contrast to GPMVs after LPS removal. GPMVs exposed to fluorescent LPS exhibited a signal that remained visible in some GPMVs even after LPS removal, which was never the case with GUVs. Calcein penetrated both into GUVs and GPMVs, however after the removal from the bulk solution some of the GPMVs still exhibited very bright signal, while in GUVs only a weak fluorescent signal was detected. We could also see that practically all GPMVs incorporated dextran initially, but after the dextran solution was changed with the initial non-fluorescent solution it remained only in 20% of them. The majority of HUVEC cells displayed a fluorescent signal after the incubation with GPMVs that contained fluorescently labeled dextran.

Conclusion

Our findings indicate that GPMVs behave quite differently from artificially made giant phospholipid vesicles and the changes induced by the different treatments we subjected them to are not reversible. We also demonstrate that different substances can be both loaded into them and delivered into cells, so GPMVs may be of potential use as cargo/therapy delivery systems.

     

Analysis of Real-world Data on Postremission Therapy for Acute Myeloid Leukemia With Intermediate Risk Cytogenetics in First Complete Remission

Background

We retrospectively analyzed data from 310 patients with acute myeloid leukemia with intermediate-risk cytogenetics in first complete remission (CR1) to evaluate the usage and efficacy of various types of postremission therapy.

Analysis of clinical data to determine the minimum number of sensors required for adequate skin temperature monitoring of superficial hyperthermia treatments

Purpose: Tumor response and treatment toxicity are related to minimum and maximum tissue temperatures during hyperthermia, respectively. Using a large set of clinical data, we analyzed the number of sensors required to adequately monitor skin temperature during superficial hyperthermia treatment of breast cancer patients.

Methods: Hyperthermia treatments monitored with >60 stationary temperature sensors were selected from a database of patients with recurrent breast cancer treated with re-irradiation (23?×?2?Gy) and hyperthermia using single 434?MHz applicators (effective field size 351–396?cm²). Reduced temperature monitoring schemes involved randomly selected subsets of stationary skin sensors, and another subset simulating continuous thermal mapping of the skin. Temperature differences (ΔT) between subsets and complete sets of sensors were evaluated in terms of overall minimum (T_min) and maximum (T_max) temperature, as well as T90 and T10.

Results: Eighty patients were included yielding a total of 400 hyperthermia sessions. Median ΔT was?<0.01?°C for T90, its 95% confidence interval (95%CI) decreased to ≤0.5?°C when?>50 sensors were used. Subsets of?<10 sensors result in underestimation of T_max up to ?2.1?°C (ΔT 95%CI), which decreased to ?0.5?°C when?>50 sensors were used. Thermal profiles (8–21 probes) yielded a median ΔT?T_max, with a 95%CI of ?0.2?°C and 0.4?°C, respectively. The detection rate of T_max?≥43?°C is?≥85% while using?>50 stationary sensors or thermal profiles.

Conclusions: Adequate coverage of the skin temperature distribution during superficial hyperthermia treatment requires the use of?>50 stationary sensors per 400?cm² applicator. Thermal mapping is a valid alternative.     

Comparison of calculated dose distributions reported as dose-to-water and dose-to-medium for intensity-modulated radiotherapy of nasopharyngeal cancer patients

Advanced dose calculation algorithms for radiation therapy treatment planning can report external beam photon dose 2-sided, in terms of dose-to-medium (D_m) and dose-to-water (D_w). The purpose of our study was to determinate the effect of D_w and D_m reporting modes built in Elekta Monaco treatment planning system on intensity-modulated radiotherapy dose distributions for patients with nasopharyngeal cancer. For 13 patients involved in this retrospective study, 2 plans were created: 1 using D_w and another according to D_m reporting mode. Treatment plans were normalized such that 100% planning target volume should be covered by 95% of prescribed dose. Dose-volume constraints were assigned according to international standards. The comparison between dose distributions was performed evaluating quantities important for respective volumes of interest. For target volumes, heterogeneity index and conformity index methodology were used along with the maximum dose concept. Also, for the comparisons over particular organ at risk, maximum dose or mean dose as well as dose-volume concepts were used. For all target volumes and majority of organs at risk, the differences between 2 reporting modes are statistically insignificant, but this is not the case for bony structured organs at risks: mandible and cochlea. It was observed that D_w is higher than D_m with mean difference of 9.91% (p?=?0.000009) of the mandible volume covered with 70?Gy. The same trend was observed for left and right cochlea with difference in mean dose of 8.74% (p?=?0.037) and 6.87% (p?=?0.029), respectively. The comparative analysis of dosimetric parameters in this study shows that the selection of reporting modes in Monaco treatment planning system can produce dose differences up to 15% in high-density volumes such as mandible and cochlea, which might have clinical consequences.     

Operative and postoperative management of congenital duodenal obstruction: a 10-year experience

Forty-five patients with congenital duodenal obstruction aged from 1 day to 11 months were operated upon during the last decade. Group A included 25 neonates with duodenal obstruction due to atresia type I or a complete diaphragm in 10 cases, atresia type II in 3, atresia type III in 1, stenosis or incomplete diaphragm in 4, annular pancreas in 6, and aberrant vessels in 1. Seven duodenoduodenostomies (D-D) were performed, 14 duodenoplasties (D-P) with occasional excision of the diaphragm, and 4 duodenojejunostomies (D-J). Tapering, plication of the proximal duodenum, or gastrostomy was not performed in any child and no transanastomotic tube was placed. Group B included 20 infants with duodenal obstruction due to peritoneal bands and associated malrotation. They all underwent Ladd's procedure. All children in group B and 15 in group A had an uneventful recovery and tolerated oral feedings within the first 10 days postoperatively without any complication. Six children in group A had prolonged postoperative ileus and were treated with total parenteral nutrition (TPN), gastric decompression, and radiologic evaluation of anastomotic patency. These 6 children eventually tolerated oral feeding between the 18th and 45th postoperative days. In 1 child a technical error was found that caused a prolonged ileus. Three children died within the 1st postoperative week. It is concluded that simple establishment of continuity of the gastrointestinal tract by performing the appropriate surgical procedure in combination with TPN and gastric decompression gives satisfactory results in the management of duodenal obstruction.Presented at the 15th Annual International Meeting arranged by the Greek Association of Pediatric Surgeons.     

Allogeneic cartilage used for skull base plasty in children with primary intranasal encephalomeningocele associated with cerebrospinal fluid rhinorrhea

Three children with primary intranasal encephalomeningocele associated with cerebrospinal fluid rhinorrhea were operated on at the Department of Neurosurgery, Hradec Králové. In two children, aged 4 and 9.5 years, freeze-dried allogeneic costal cartilage was glued into the skull base defect. This plugging was covered up with deepfrozen allogeneic fascia lata. In the third child, an only 1-year-old boy, after transection of the neck of the encephalomeningocele freeze-dried allogeneic dura mater was glued on extradurally and deep-frozen allogeneic fascia lata applied intradurally. The cerebrospinal fluid rhinorrhea ceased immediately after surgery. Spontaneous atrophy of the intranasal portion of the encephalomeningocele was demonstrated respectively 11, 1, and 7 years postoperatively on computed tomography. To evaluate cartilage healing histologically, the extracted allogeneic cartilage used for orbital roof plasty after 4 months was examined. The extent of spotty regressions represented about 7% of the tissue volume. It is stressed that, once diagnosed, intranasal encephalomeningocele associated with cerebrospinal fluid rhinorrhea should be operated on for prevention of meningitis as soon as possible.     

Sex differences in conflict behaviour and in plasma corticosterone levels

Summary The levels of plasma corticosterone and conflict behaviour were followed in male and female water deprived Wistar rats exposed to the punished (0.2 or 0.8 mA) drinking test. The unpunished drinking, performed under familiar or unfamiliar conditions, and plasma corticosterone levels of these male and female rats were determined. Plasma corticosterone was elevated in water-deprived rats compared to rats under normal conditions. In all cases plasma corticosterone levels were considerably higher in water deprived females than in males. The highest levels in both sexes were obtained following drinking punished with 0.8 mA shocks. While the unpunished drinking did not differ between the two sexes, the punished drinking was significantly lower in females than in males. Although female rats displayed less punished licks and had higher plasma corticosterone levels than males, there was no correlation between the two parameters.