The fate of cells with chromosome aberrations after total-body irradiation and bone marrow transplantation

Cytogenetic studies were done on bone marrow cells and peripheral lymphocytes of four patients (three with acute nonlymphocytic leukemia, one with aplastic anemia) at various intervals up to 861 days after total-body X irradiation (TBI) at doses between 4.5 and 10 Gy (450-1000 rad) followed by syngeneic or allogeneic bone marrow transplantation. Whereas no radiation-induced aberrations could be found in the bone marrow, apart from a transient finding in the patient with the lowest radiation dose, aberrant metaphases were seen in the peripheral lymphocytes of three patients in the range from 2.5 to 46% even at 861 days after the exposure. There were no demonstrable aberrations related to TBI in the only patient developing graft-versus-host disease. The dicentric yield as determined in the aberrant metaphases with 46 centromeres ranged between 3.4 +/- 1.3 and 4.9 +/- 0.4. In one patient it was demonstrated by BUdR-labeling that after 10 Gy (1000 rad) TBI the surviving and heavily damaged lymphocytes can go into cell cycle and reach at least the third mitosis. The percentage of aberrant cells diminished by about 25% at each mitotic division.     

Kinematographische Dokumentation einer amitotischen Zellteilung

Summary Identification of argyrophilic cells, in pancreatic islets of normal rabbits, is accomplished by light and electron microscopy in osmium-fixed plastic-embedded tissues.Fixative, pretreatment and pH of silver nitrate solution were essential for the light microscopic study to reveal argyrophilic cells in osmium-fixed plastic-embedded pancreatic islet tissue. The best result was obtained with Dalton's osmium fixation and buffered silver nitrate methanamine solution at pH 9.O. The cytoplasmic granules of argyrophilic cells generally are densely packed but some of the cells show only sparse silver impregnated granules in the cytoplasm. Occasionally there are some non-argyrophilic granular cells in which, after silver impregnation, the cytoplasm appears clear. There are three kinds of cells in the pancreatic islets, i.e., argyrophilic granular cells, non-argyrophilic granular (clear) cells, and beta cells (situated centrally in the islet and stained light yellow in silver impregnated sections).The cells known as argyrophilic cells in light microscopy can be identified as alpha cells in electron micrographs by comparison of consecutive sections of the same cell.The author would like to express his appreciation to professor Roy C. Swan for his generous guidance.     

Stem cells from peripheral blood and bone marrow: a comparative evaluation of the hemopoietic potential in the dog

The kinetics and pattern of hemopoietic recovery after supralethal total-body irradiation (TBI) were compared after transfusion of cryopreserved autografts derived from peripheral blood and bone marrow. Fractionated TBI was given in three doses of 6 Gy each at intervals of 48 h. Grafts of peripheral blood mononuclear cells (MNC) were collected by means of continuous-flow centrifugation and by using the mobilizing agent, dextran sulphate. Autografts were adjusted to contain equal numbers of committed progenitor cells (CFU-GM). Dogs grafted with blood-derived MNC (group A) and with MNC from bone marrow (group B) all received about 1 X 10(5) CFU-GM per kg body weight. In all dogs consistent hemopoietic engraftment was achieved. Comparing the pattern of regeneration of the granulocytes, group A dogs showed a significant regeneratory advantage over group B dogs, particularly during the first 20 days after transplantation. Lymphoid recovery was more rapid in group A until day 14. In both groups, blood lymphocytes remained below normal values beyond day 100. The regeneration patterns of the platelets and reticulocytes revealed no significant differences. These results are in agreement with the hypothesis that there are differences in the relationship between CFU-GM content and hemopoietic potential of autografts from different sources.     

Risk factors of peripheral arterial disease: a case control study in Sri Lanka

Background

Peripheral artery disease (PAD) is an important global health problem and contributes to notable proportion of morbidity and mortality. This particular manifestation of systemic atherosclerosis is largely under diagnosed and undertreated. For sustainable preventive strategies in a country, it is mandatory to identify country-specific risk factors. We intended to assess the risk factors of PAD among adults aged 40–74 years.

Methods

This case control study was conducted in 2012–2013 in Sri Lanka. Seventy-nine cases and 158 controls in the age group of 40–74 years were selected for the study in order to have case to control ratio 1:2. The criterion for selecting cases and control was based on Ankle brachial pressure index (ABPI). Cases were selected from those who had ABPI 0.85 or less (ABPI ≤0.85) in either lower limb. Controls were selected from those ABPI score between 1.18 and 1.28 in both lower limbs. Only newly identified individuals with PAD were selected as cases. Controls were selected from the same geographical location and within the 5 year age group as cases.

Results

The history of diabetes mellitus more than 10 years (OR 5.8, 95% CI 2.2–14.2), history of dyslipidemia for more than 10 years (OR 4.9, 95% CI 2.1–16.2), history of hypertension for more than 10 years (OR 3.8, 95% CI 1.8–12.7) and smoking (OR 2.9, 95% CI 1.2–6.9), elevated HsCRP (OR 3.7, 95% CI 1.2–12.0) and hyperhomocysteinemia (OR 3.0, 95% CI 1.1–8.1) were revealed as country specific significant risk factor of PAD.

Conclusions

Diabetes mellitus, hypertension, dyslipidemia, smoking as well as elevated homocysteine and HsCRP found as risk factors of PAD. Longer the duration or higher level exposure to these risk factors has increased the risk of PAD. These findings emphasis the need for routine screening of PAD among patients with the identified risk factors.

     

The role of fish-poultry integration on fish growth performance,yields and economic benefits among smallholder farmers in sub-Saharan Africa,Tanzania

Aquaculture practices from sub-Saharan Africa are characterised by low production, owing to improper technology. Production can be increased through integrating fish farming with other existing on-farm activities, particularly livestock husbandry. We assessed the role of fish-poultry integration on all male Nile tilapia, Oreochromis niloticus growth performance, yields and economic benefits among smallholder farmers in sub-Saharan Africa, Tanzania. The study also compared phytoplankton species composition, abundance and biomass between the fish-poultry integration and non-integrated system. After 180 days of the experiment, all male O. niloticus cultured under fish-poultry integration exhibited significantly higher growth rates than those in the non-integrated system (p < 0.05). Gross fish yield (GFY), net fish yield (NFY) and net annual yields (NAY) obtained from fish-poultry integration were significantly higher than those from non-integrated system (p < 0.05). Partial enterprise budget analysis revealed that fish-poultry integration was more profitable than the non-integrated system. Moreover, fish-poultry integrated system produced significantly higher phytoplankton abundance and biomass than those from the non-integrated system. Results demonstrate that rural smallholder farmers can achieve higher growth rate, farm net yields and income by integrating all male O. niloticus with other on-farm activities than practising a stand-alone fish culture system.     

Laser pyrolysis products-genotoxic, clastogenic and mutagenic effects of the particulate aerosol fractions

Laser therapy has gained wide acceptance and application in many medical disciplines. Nevertheless, during surgical procedures, the thermal destruction of tissue creates a smoke plume. Recent research data indicate that pyrolysates liberated during vaporisation of tissue induce DNA damage. However, assessing potential health hazards during medical laser treatment requires comprehensive insight into the cytotoxic, genotoxic, clastogenic and mutagenic capacity of laser pyrolysis products (LPP). Therefore, the aim of this study was to evaluate the cytotoxic, genotoxic, clastogenic and mutagenic potential of substances resulting from laser irradiation. Four different types of porcine tissues were irradiated with a surgical CO2 laser, the aerosols were sampled under defined conditions and subjected to the SCE test, micronucleus test and the HPRT test. The results showed that the pyrolysis products are strong inducers of cytotoxic effects. The pyrolysis products induced positive effects in the SCE test, micronucleus test and the HPRT test. The ability and extent to induce genotoxic and mutagenic effects turned out to be dependent on the type of tissue that had been irradiated. In general, the effects were most pronounced with liver pyrolysate. In all test systems, a clear dose relationship could be established. In conclusion, we were able to prove that the particulate fraction of laser pyrolysis aerosols originating from biological tissues undoubtedly have to be classified as cytotoxic, genotoxic, clastogenic and mutagenic. Therefore, they could be potential health hazards for humans.     

SEARCH: a system for evaluation and archiving of radiation accidents based on case histories

Overexposure of humans to ionizing radiation has occurred worldwide in the past and will surely occur again in the future. In order to allow an effective radiation accident management, it is consequently necessary to be prepared for such emergency situations and to improve means and ways to help people suffering from radiation-induced health impairments. Such approaches should rely on knowledge and experience gained from previous radiation incidents. A prerequisite for any scientific evaluation and comparison of information related to radiation accidents is to collect data in a standardized way. Therefore, the SEARCH database (System for Evaluation and Archiving of Radiation accidents based on Case Histories) has been developed in our department and implemented as an Oracle 8.0 database containing to date more than 800 case histories. The use of this registry is so far limited to active contributors and requires each contributor to sign a cooperation agreement. More information is available under http://www.faw.uni-ulm.de/radmed/. Received: 7 February 2000 / Accepted: 8 May 2000