Radiation-induced lowered neurogenesis associated with shortened latency of inhibitory avoidance memory response

The neural system is less sensitive to radiation than other late-responding organs and tissues such as the kidney and lung. The generation of new neurons in the adult mammalian brain has been documented in several works. Many studies show that adult hippocampal neurogenesis relates to hippocampal function, in several ways. In this study, we assessed the effect of single and fractionated cobalt radiation on neurogenesis in the dentate gyrus of the hippocampal formation. The irradiation time for delivering 2 Gy (for fractionated dose radiation) and 10 Gy (for single dose radiation) at maximum depth were respectively 1.98 min and 9.92 min. To study the association with memory function we examined inhibitory avoidance memory using a step-through device. Brains were withdrawn and fixed, and then sections were stained with cresyl violet for neurons. We found that a 10 Gy dose can induce lower neurogenesis in the dentate gyrus of the hippocampus (p < 0.05), in such a way that a fractionated dose (5 fractions of 2 Gy) is more effective than a single dose (one fraction of 10 Gy). Moreover, a fractionated dose could reduce step-through latency corresponding to damaged inhibitory avoidance memory (p < 0.05). Synergic action of an anaesthetic drug may be the cause of more reduction of neurogenesis in fractionated irradiated rats. There was no significant difference in latency of the inhibitory avoidance memory response between the single 10 Gy group and the sham group, while fractionated 10 Gy could reduce latency. Different mechanisms of action in the two regimens of irradiation may be a reason

Disease severity adversely affects delivery of dialysis in acute renal failure

Background/Aims: Methods of intermittent hemodialysis (IHD) dose quantification in acute renal failure (ARF) are not well defined. This observational study was designed to evaluate the impact of disease activity on delivered single pool Kt/V-urea in ARF patients. Methods: 100 patients with severe ARF (acute intrinsic renal disease in 18 patients, nephrotoxic acute tubular necrosis in 38 patients, and septic ARF in 44 patients) were analyzed during four consecutive sessions of IHD, performed for 3.5-5 h every other day or daily. Target IHD dose was a single pool Kt/V-urea of 1.2 or more per dialysis session for all patients. Prescribed Kt/V-urea was calculated from desired dialyzer clearance (K), desired treatment time (t) and anthropometric estimates for urea distribution volume (V). The desired clearance (K) was estimated from prescribed blood flow rate and manufacturer's charts of in vivo data obtained in maintenance dialysis patients. Delivered single pool Kt/V-urea was calculated using the Daugirdas equation. Results: None of the patients had prescription failure of the target dose. The delivered IHD doses were substantially lower than the prescribed Kt/V values, particularly in ARF patients with sepsis/septic shock. Stratification according to disease severity revealed that all patients with isolated ARF, but none with 3 or more organ failures and none who needed vasopressive support received the target dose. Conclusion: Prescription of target IHD dose by single pool Kt/V-urea resulted in suboptimal dialysis dose delivery in critically ill patients. Numerous patient-related and treatment-immanent factors acting in concert reduced the delivered dose. Copyright (C) 2007 S. Karger AG, Basel

Effect of Single Dose of Minocycline on a Chloroquine Resistant Falciparum Infection From Balikpapan, Kalimantan

Selain 3 kasus P. falciparum yang resistent terhadap chloroquine dari Samarinda (Verdrager &amp; Arwati, 1974) baru-baru ini ditemukan lagi satu kasus juga dari Kalimantan Timur, tetapi dari daerah yang lain (Balikpapan). Terhadap kasus yang terakhir ini dilaksanakan sensitivity test sesuai dengan standar WHO. Disamping test tersebut, kepada penderita diberikan pula sensitivity test dengan 300 mg minocycline secara single dose. Minocycline yang merupakan derivat dari tetracyclin mempunyai khasiat anti malaria. Pengobatan radical dapat dicapai (pada 9 penderita sukarela yang menderita malaria strain tdari Vietnam) sesudah 7 hari pengobatan. Dengan pemberian 300 mg minocycline base secara single dose, bentuk asexual dari parasite menghilang untuk jangka waktu 2 minggu. Effek ini sama dengan effek pemberian 1.500 mg chloroquine base, hanya hilangnya parasit bentuk asexual lebih lambat. Pemberian pengobatan dengan minocycline dengan jangka yang lebih lama sebagai yang dikemukakan oleh WHO (1975) mungkin dapat mengobati radikal strain P. falciparum yang resistent terhadap chloroquine

Single-grain dose-distribution measurements by optically stimulated luminescence using an integrated EMCCD-based system

We report on the feasibility of assessing single-grain dose-distributions by using an EMCCD-based imaging system with complementary analysis software. Automated image-processing was successfully applied to compensate sample motion and for automated grain identification. Following a dose recovery test, 74 % of the grains were recognized successfully, and 44 % exhibited a suitable OSL dose response behavior to interpolate an equivalent dose value and a central dose recovery ratio of 1.038 was obtained.Comment: 30 pages, 6 figures, 2 table

Single high-dose buprenorphine for opioid craving during withdrawal.

BackgroundOpioid use disorder is one of the most prevalent addiction problems worldwide. Buprenorphine is used as a medication to treat this disorder, but in countries where buprenorphine is unavailable in combination with naloxone, diversion can be a problem if the medication is given outside a hospital setting.ObjectiveThe objective of this research is to evaluate the effect of a single, high dose of buprenorphine on craving in opioid-dependent patients over 5 days of abstinence from use of other opioids. The primary goal was to determine the safety and efficacy of buprenorphine during withdrawal in a hospital setting.MethodsNinety men who used opium, heroin, or prescribed opioids and met DSM-5 criteria for opioid use disorder (severe form) were randomized to three groups (n = 30 per group) to receive a single, sublingual dose of buprenorphine (32, 64, or 96 mg). The study was conducted in an inpatient psychiatric ward, with appropriate precautions and monitoring of respiratory and cardiovascular measures. Buprenorphine was administered when the patients were in moderate opiate withdrawal, as indicated by the presence of four to five symptoms. A structured clinical interview was conducted, and urine toxicology testing was performed at baseline. Self-reports of craving were obtained at baseline and on each of the 5 days after buprenorphine administration.FindingsCraving decreased from baseline in each of the three groups (p &lt; 0.0001), with a significant interaction between group and time (p &lt; 0.038), indicating that groups with higher doses of buprenorphine had greater reduction.ConclusionsA single, high dose of buprenorphine can reduce craving during opioid withdrawal; additional studies with follow-up are warranted to evaluate safety

A dose-ranging study in older adults to compare the safety and immunogenicity profiles of MF59®-adjuvanted and non-adjuvanted seasonal influenza vaccines following intradermal and intramuscular administration

Strategies to optimize responses to seasonal influenza vaccination in older adults include the use of adjuvants, higher antigen doses, and intradermal delivery. In this study adults aged >= 65 years (n = 450) received a single dose of 1 of 2 non-adjuvanted trivalent influenza vaccine (TIV) formulations administered intradermally (ID), both containing 6 mu g of A/H1N1 and B, differing in A/H3N2 content (6 mu g or 12 mu g), or a single dose of 1 of 8 TIV formulations administered intramuscularly (IM) all containing 15 mu g of A/H1N1 and B, differing in A/H3N2 hemagglutinin (HA) content (15 mu g or 30 mu g) and/or in MF59 (R) adjuvant content (0%, 25%, 50%, or 100% of the standard dose). This paper focuses on the comparisons of low-dose non-adjuvanted ID, full-dose non-adjuvanted IM and full-dose MF59-adjuvanted IM formulations (n = 270). At day 22 post-vaccination, at least one European licensure immunogenicity criterion was met by all groups against all 3 strains; however, all three criteria were met against all 3 vaccine strains by the low-dose non-adjuvanted ID and the full-dose MF59-adjuvanted IM groups only. The full-dose MF59-adjuvanted IM group elicited significantly higher immune response vs. the low-dose non-adjuvanted ID formulations for most comparisons. The full-dose MF59 adjuvanted IM groups were associated with increased pain at the site of injection (P < 0.01) compared to the ID groups, and the low-dose non-adjuvanted ID groups were associated with increased erythema, induration, and swelling at the injection site (P < 0.0001) and unsolicited AEs compared with the IM groups. There were no differences between IM and ID groups in the frequencies of subjects experiencing solicited systemic reactions. Overall, while MF59 adjuvantation increased pain at the site of injection, and intradermal delivery increased unsolicited adverse events, erythema, induration, and swelling at the injection site, both strategies of vaccination strongly enhanced the immunogenicity of seasonal influenza vaccine in older adults compared with conventional non-adjuvanted intramuscular delivery

Immunogenicity and tolerability of an MF59-adjuvanted, egg-derived, A/H1N1 pandemic influenza vaccine in children 6-35 months of age

Background: Vaccines against pandemic A/H1N1 influenza should provide protective immunity in children, because they are at greater risk of disease than adults. This study was conducted to identify the optimal dose of an MF59 (R)-adjuvanted, egg-derived, A/H1N1 influenza vaccine for young children. Methods: Children 6-11 months (N = 144) and 12-35 months (N = 186) of age received vaccine formulations containing either 3.75 mu g antigen with half the standard dose of MF59 or 7.5 mu g antigen with a standard dose of MF59, or a nonadjuvanted formulation containing 15 mu g antigen (children 12-35 months only). Participants were given 2 primary vaccine doses 3 weeks apart, followed by 1 booster dose of MF59-adjuvanted seasonal influenza vaccine 1 year later. Immunogenicity was assessed by hemagglutination inhibition and microneutralization assays. Results: All vaccine formulations were highly immunogenic and met all 3 European licensure criteria after 2 doses. MF59-adjuvanted vaccines met all licensure criteria after 1 dose in both age cohorts, while nonadjuvanted vaccine did not meet all criteria after 1 dose in children 12-35 months. A single booster dose was highly immunogenic, and stable antibody persistence was observed in response to all vaccines. All vaccines were well tolerated. Conclusions: In this study, a single dose of 3.75 mu g antigen with half the standard dose of MF59 was shown to be optimal, providing adequate levels of immediate and long-term antibodies in pediatric subjects 6-35 months of age. These data demonstrated that MF59 adjuvant allowed for reduced antigen content and promoted significant long-term antibody persistence in children, with a satisfactory safety profile

The variance-covariance method: Microdosimetry in time-varying low dose-rate radiation fields

The variance-covariance method is employed at low doses and in radiation fields of low dose rates from an241Am (4 nGy/s) and a90Sr (300 nGy/s) source. The preliminary applications and results illustrate some of the potential of the method, and show that the dose average of lineal energy or energy imparted can be determined over a wide range of doses and dose rates. The dose averages obtained with the variance-covariance method in time-varying fields, for which the conventional variance method is not suitable, agree well with results obtained under the condition of constant dose rate. The results are compared to data obtained in terms of the conventional single-event measurements. The method has evident advantages, such as facility and speed of measurement