Pathological effects of gentamicin administered intramuscularly to day-old broiler chicks

The aim of this experimental study was to investigate the pathological effects of gentamicin in birds. Broiler chicks at 1 day of age were intramuscularly administered gentamicin at dose levels varying from 0 to 180 mg/kg. Clinical signs comprising of depression, decreased feed consumption, increased water intake, loose watery droppings and reduced body weights appeared in a dose-related manner in chicks administered 30 mg/kg or higher dose levels. Mortality was 0% and 20% in chicks given 40 mg and 50 mg/kg gentamicin. It increased in a dose-related manner and was 100% in 100 mg/kg or higher dose groups. The LD50 calculated at total deaths in 5 weeks duration was 77.56 mg/kg. Kidneys and livers of chicks given 50 mg/kg or higher doses of gentamicin were congested, enlarged and had hemorrhages on the surfaces. Microscopically kidneys exhibited acute tubular necrosis. Livers showed fatty change, vacuolar degeneration, necrotic areas and cellular infiltration around portal triads. Serum total proteins and albumin decreased while creatinine and ALT increased in chicks given 20 mg/kg and higher doses. The no observable effect level (NOEL) of a single intramuscular administration of gentamicin in day-old broiler chicks was 10 mg/kg body weight.     

Correlation and prediction of a large blood-brain distribution data set--an LFER study.

We report linear free energy relation (LFER) models of the equilibrium distribution of molecules between blood and brain, as log BB values. This method relates log BB values to fundamental molecular properties, such as hydrogen bonding capability, polarity/polarisability and size. Our best model of this form covers 148 compounds, the largest set of log BB data yet used in such a model, resulting in R(2)=0.745 and e.s.d.=0.343 after inclusion of an indicator variable for carboxylic acids. This represents rather better accuracy than a number of previously reported models based on subsets of our data. The model also reveals the factors that affect log BB: molecular size and dispersion effects increase brain uptake, while polarity/polarisability and hydrogen-bond acidity and basicity decrease it. By splitting the full data set into several randomly selected training and test sets, we conclude that such a model can predict log BB values with an accuracy of less than 0.35 log units. The method is very rapid-log BB can be calculated from structure at a rate of 700 molecules per minute on a silicon graphics O(2).     

Plasma iron status and lipid peroxidation following thrombolytic therapy for acute myocardial infarction

Summary— Free radical species have been implicated as important agents involved in myocardial ischemic and reperfusion injuries. Superoxide is capable of mobilizing iron from ferritin and the released iron can cause hydroxyl formation from H₂O₂. The aim of this study was to evaluate the time-dependent increase in lipid peroxidation assessed by plasma thiobarbituric acid reactive substances (TBARS) and the relationship between lipid-peroxidation and the iron status. Peripheral venous blood samples were obtained from 17 men with acute myocardial infarction (AMI) before thrombolytic treatment (T0***) and 1, 2, 3, 4, 8, 12, 16, 20, 24 and 48 hours after commencing fibrinolytic treatment. The concentration of TBARS, the parameters of iron metabolism, serum myoglobin, creatine kinase, and creatine kinase-MB were measured. Early reperfusion was judged by regression of sinus tachycardia (ST) elevation and reduction of chest pain. Recanalization of coronary artery was evaluated by a late coronary angiography 24–96 hours after thrombolysis. After thrombolytic therapy, the TBARS level was raised from 2.98 ± 0.80 (T0***) to 4.57 ± 1.24 (peak), and decreased to 2.96 ± 0.40 nmol/mL plasma at T48 (T0 vs peak: P < 0.001, peak vs T48: P < 0.001, TO vs T48: NS). The mean time of the peak was observed at 9.7 ± 7.5 hours. The iron increased significantly from 0.67 ± 0.34 (T0) to 1.15 ± 0.52 mg/L (peak), and returned to the pre-reperfusion to levels: 0.53 ± 0.28 UI/L at T48 (T0 vs peak: P < 0.001, peak vs T48: P < 0.001, TO vs T48: NS). The mean time of the peak was observed at 9.4 ± 7.3 hours. In return, no correlation was found between the increase of plasma creatine-kinase activity, myoglobin and iron or between the biochemical markers and time of fibrinolytic therapy. The results confirmed the importance of the temporal relationship between lipid peroxidation and iron status after thrombolytic therapy. Our results are in agreement with the concept that antioxidant agents used in association with thrombolytic therapy might be useful.     

Assessment of Trace Metal and Metalloid Accumulation and Human Health Risk from Vegetables Consumption through Spinach and Coriander Specimens Irrigated with Wastewater

This study focused on evaluating the metal and metalloid contamination and associated risks in the two vegetables crops, coriander (Coriandrum sativum) and spinach (Spinacia oleracea) treated with three water regimes, canal water, groundwater and municipal wastewater. These vegetables are widely consumed by people and are also used in traditional medicine for treating various disorders. Metal and metalloid accumulation (Zn, Pb, Se, Cu, As, Mo, Fe, Ni) was found higher in vegetables treated with wastewater. Wastewater treated soil had high pollution load index. Fe, Zn, As and Pb had higher values in water, soil and vegetables as compared to other studied metals. Overall, metal correlation for soil and vegetables was significant and positive except for Fe and Cu in spinach. The highest value for daily metal intake was estimated for Fe while Se had the lowest value for the same index. It was thus concluded that trace metal and metalloid accumulation was a major health concern for the public consuming these vegetables.     

Direct demonstration that autologous bone marrow transplantation for solid tumors can return a multiplicity of tumorigenic cells

Patients with solid tumors are increasingly being treated by autologous bone marrow transplantation (BMT). Although response rates appear to be increased, disease recurrence is the commonest cause of treatment failure. Whether relapse is entirely due to residual disease in the patient or arises also from infiltrating malignant cells contained in the autologous marrow transplant has not been resolved. If the latter explanation is correct, then purging would be required as part of the transplantation procedure. We used retrovirally mediated transfer of the neomycin-resistance gene to mark BM harvested from eight patients with neuroblastoma in clinical remission. The marked marrow cells were subsequently reinfused as part of an autologous BMT. At relapse, we sought the marker gene in malignant cell populations. Three patients have relapsed, and in each the marker gene was detected by phenotypic and genetic analyses of resurgent malignant cells at medullary and extramedullary sites. Analysis of neuroblast DNA for discrete marker gene integration sites suggested that at least 200 malignant cells, each capable of tumor formation, were introduced with the autologous marrow transplant and contributed to relapse. Thus, autologous BMTs administered to patients with this solid tumor may contain a multiplicity of malignant cells that subsequently contribute to relapse. The marker-gene technique we describe should permit evaluation of the mechanisms of relapse and the efficacy of purging in patients receiving autologous marrow transplantation for other solid tumors that infiltrate the marrow.     

Takayasu arteritis of subclavian artery in a Caucasian

Takayasu arteritis, an inflammatory and obliterative disease of medium and large arteries, is classified as a giant cell arteritis. It has a predilection for the aortic arch, its main branches, and coronary and pulmonary arteries. The early symptoms of Takayasu arteritis may be mainly systemic and may resemble polymyalgia rheumatica. The etiology is unknown but autoimmunity has been suggested to play a role. Diagnosis is based on symptoms, physical findings, and imaging, because tissue diagnosis is rarely feasible. Unlike atherosclerotic vascular disease, Takayasu arteritis affects primarily, but not exclusively, young women. Contrary to earlier reports, it is not limited to the women of Japanese origin but is present worldwide. The current report is of a Caucasian woman who presented with nonspecific complaints of upper back pain, weakness, malaise, and fatigue. Her physical examination revealed absent left radial pulse and a blood pressure differential, later confirmed by radiological imaging studies to be due to left subclavian artery stenosis consistent with Takayasu arteritis. The presentation and management of the patient is described, and Takayasu arteritis is succinctly reviewed.