Penetration of amikacin into aqueous humor of rabbits

Amikacin is an aminoglycoside antibiotic that has poor corneal penetration due to its hydrophilic properties. The purpose of this study was to compare and evaluate the penetration of amikacin sulfate into aqueous humor of the rabbit eye when applied by different routes and concentrations, namely 100 or 250 mg/ml topical fortified amikacin eye drops, 100 or 250 mg/ml amikacin-embedded soft contact lenses and 25 mg subconjunctival amikacin injection. One hour after application, amikacin was not detectable in any of the 100 mg/ml concentration groups. High levels of amikacin above the minimum inhibitory concentration for susceptible bacteria were detected when applied subconjunctivally and by 250 mg/ml topical fortified routes. Topical fortified amikacin 250 mg/ml reached the highest value in the aqueous (p < 0.05). Our results point out the poor corneal penetration of amikacin in standard concentrations from the intact rabbit cornea and that subconjunctival injections might provide satisfactory penetration.     

The in-vitro and in-vivo characterization of PLGA:L-PLA microspheres containing dexamethasone sodium phosphate

Dexamethasone sodium phosphate (DSP) is a widely used corticosteroid in the treatment of brain oedema associated with brain tumours. DSP has many side effects that limit its usage at an effective concentration. The objective of this study was to minimize these side effects by encapsulating DSP using biodegradable synthetic polymers, to extend the release time from microspheres and to evaluate the effectiveness in the treatment of brain oedema. Microspheres containing 5% DSP were formulated by the solvent evaporation method by using a 1:1 mixture of two synthetic polymers, poly(lactic-co-glycolic acid) and L-polylactic acid (PLGA and L-PLA). The surface morphologies and particle size distribution of the microspheres were investigated. The in-vitro release studies were performed in pH 7.4 phosphate buffer solution. For determining the effectiveness of microspheres in the treatment of brain oedema, Sprague-Dawley rats weighing 200-250g were used as an animal model. Brain oedema was generated by the cold lesion method, and the effectiveness of the microspheres in treatment of oedema was investigated by the wet-dry weight method, lipid peroxidation ratios and histological evaluations. The average particle size of the microspheres was 13.04 +/- 2.05 microm, and the in-vitro release time of the microspheres was 8 h for 100/release. The degree of oedema was significantly different from the control group for the wet-dry weight method and lipid peroxidation ratio (p < 0.05). Similarly, histological evaluation of the tissues shoved that degree of oedema was significantly decreased with respect to the control group. All these results showed that implantation of microspheres was significantly more effective with respect to the systemic administration of DSP.     

p53, p21 and metallothionein immunoreactivities in patients with malignant pleural mesothelioma: correlations with the epidemiological features and prognosis of mesotheliomas with environmental asbestos exposure.

The aim of this study is to investigate immunoreactivity for p53, p21 and metallothionein in diffuse malignant pleural mesothelioma (DMPM) and to determine the relationships between the age, sex, asbestos exposure time, survival of DMPM patients with environmental asbestos exposure and immunoreactivity to p53, p21 and metallothionein. Sixty-seven histopathologically-confirmed DMPMs, 38 of whom had environmental and 29 had occupational asbestos exposure, were included. The tumour tissue samples were immunostained with antibodies against p53, p21 and metallothionein. Epidemiological data and the survival times for the DMPM patients with environmental asbestos exposures were obtained from hospital records. Thirty-three per cent of the DMPMs were positive for p53, 35% for p21 and 52% for metallothionein. There was no statistical difference between the histological subtypes of DMPM in terms of immunoreactivity for p53, p21 and metallothionein. For p21 and metallothionein there was a statistically significant difference between the exposure characteristics: patients with environmental asbestos exposure had shown more immunopositivity. There were statistically significant differences between age groups and between asbestos exposure times for metallothionein, and between asbestos exposure times and p21. The patients with positive immunostaining had longer exposure times and were older than those having negative immunostaining. The differences between survival of the patients were not statistically significant in terms of the immunohistochemical results for p53, p21 and metallothionein.     

Evaluation of leukocyte arylsulphatase a, serum interleukin-6 and urinary heparan sulphate following tamoxifen therapy in breast cancer.

Leukocyte arylsulphatase A (AS-A) was shown to be significantly high in newly-diagnosed breast cancer patients. Previous reports imply a connection between serum interleukin-6 (IL-6) and breast cancer, possibly through a modulation of enzymes involved in estrogen synthesis. Abnormal distribution of heparan sulphate proteoglycans (HSPGs) in malignant breast epithelial cells suggests that they play a key role in the regulation of cell growth. Estradiol is believed to be effective in modulating glycosaminoglycans (GAGs) and their depolymerizing enzymes. Therefore, in this study, attempts were made to evaluate the activity of leukocyte arylsulphatase A, serum interleukin-6, urinary GAGs and heparan sulphate (HS) in response to tamoxifen (TAM) therapy in mastectomised breast cancer patients. Thirty-four patients (aged 30-82 years) were administered TAM (20 mg twice daily). Blood and urine samples of each patient were collected three times (at the beginning, and in third and sixth month of TAM therapy), and biochemical parameters were measured. There was no difference between baseline leukocyte AS-A activity and that measured after three months. At the end of six months, enzyme activity was significantly higher than the former values (p=0.022), but within the reference intervals reported in the literature. Although this increase might imply a normalization, the duration of TAM therapy is not long enough to make a decision about either regression or aggravation of the disease. TAM did not have any effect on serum IL-6, urinary HS and GAG levels which may be due to insensitivity of these variables to TAM during the short period of therapy. Both urinary GAG and HS levels measured at sixth month exhibited a positive correlation with the baseline level of leukocyte AS-A (p=0.005 and 0.009, respectively), suggesting that positive responses to the drug might be seen in patients with low AS-A activity.     

Determination of the pericardial to serum myoglobin ratio for the early diagnosis of perioperative myocardial infarction after coronary artery bypass grafting.

Pericardial fluid reflect the composition of cardiac interstitium in myocardial ischemia. This study investigated the value of the pericardial and serum myoglobin (MG) measurements for the diagnosis of perioperative myocardial infarction (MI) after coronary artery bypass grafting (CABG). Postoperative arterial and pericardial blood samples were taken in 64 subjects undergoing elective CABG allocated to two groups according to the 12-lead electrocardiogram (ECG) abnormalities observed during the first postoperative 24h. Group 1=normal and nonspecific ECG abnormalities, and Group 2=perioperative Q-wave MI. The occurrence of perioperative MI was associated with a dramatic increase in both serum and pericardial cardiac troponin I (CTnI) and MG concentrations. Pericardial concentrations were higher than serum concentrations during the first postoperative 24h in all subject. However, pericardial/serum CTnI ratio in subjects in Group 2 was not statistically different from Group 1 at the time of admission to the intensive care unit (ICU) and did not significantly change at time intervals. On the other hand, more than two-fold increase in the pericardial/serum MG ratio was determined for all patients who experienced perioperative Q-wave MI with the lowest value as 2.75, whereas only 1 of 59 patients in group 1 had the ratio higher than 2 with the highest value as 2.15 at the time of admission to the ICU. In conclusion, determination of pericardial/serum MG ratio may be a useful tool for the early diagnosis of the perioperative MI after CABG.     

Low-fluence photodynamic therapy combinations in the treatment of exudative age-related macular degeneration

AIM: To compare the efficacy of low-fluence photodynamic therapy (PDT) combinations in the treatment of age-related macular degeneration (AMD). METHODS: Forty-five previously untreated eyes of 45 patients with exudative AMD whose best-corrected visual acuity (BCVA) was ≥0.3 (Snellen) were enrolled. 15 patients in Group I underwent low-fluence PDT (25J/cm2-300mW/cm2-83sec) and intravitreal pegaptanib combination, 15 patients in Group II underwent PDT (50J/cm2-600mW/cm2-83sec) and intravitreal pegaptanib combination while, 15 patients in Group III underwent intravitreal pegaptanib monotherapy. Complete ophthalmologic examinations were performed in pre and post treatment visits, and the results were statistically analised. A clinical activity score (CAS) was calculated by using changes in lesion size, amount of hemorrhage, staining pattern in FA and OCT measurement of intra/subretinal fluid. ≤ 3 logMAR lines of decrease in BCVA and decrease in CAS were considered as successful treatment. RESULTS: The mean age of 19 female (42.2%) and 26 male (57.8%) patients was 72.82±8.02 years. Mean follow-up was 13.93±5.87 months. Lesion type was occult in 28 eyes (62.2%). Treatment success rates according to BCVA assessments were 86.7%, 80%, 60% and mean BCVA decrease were 0.3, 1.0, 2.2 logMAR lines in Group I, II and III, respectively (P>0.05). According to the changes in central macular thickness and CAS, no difference was found among the study groups (P=0.850 and P=0.811, respectively). Patients treated with combination regimens had lower intravitreal injection frequencies (P=0.015). CONCLUSION: Combination regimen with intravitreal pegaptanib and low-fluence PDT seems to be safe and effective in stabilizing the clinical activity and BCVA in exudative AMD.     

Acute toxicity, behavioral changes, and histopathological effects of deltamethrin on tissues (gills, liver, brain, spleen, kidney, muscle, skin) of Nile tilapia (Oreochromis niloticus L.) fingerlings

Deltamethrin, a synthetic pyrethroid contaminating aquatic ecosystems as a potential toxic pollutant, was investigated in the present study for acute toxicity. The purpose of this study was to evaluate LC(50) values of deltamethrin on Nile tilapia (Oreochromis niloticus L.) fingerlings and investigate histopathological responses of fish exposed to deltamethrin. The 48 h LC(50) value for Nile tilapia fingerlings was estimated as 4.85 microg/L using static test system. In addition, behavioral changes at each deltamethrin concentration were observed closely. All fish, exposed to 5 microg/L deltamethrin revealed severe morphological alterations in the gills and liver. In the gills hyperemia, fusion of secondary lamellae and telangiectasis were observed; whereas hydropic degenerations in liver were observed in all examined fish. The results are significant for reporting acute deltamethrin toxicity in terms of behavioral and histopathological changes: Deltamethrin is highly toxic to fingerlings.     

Bilateral massive choroidal hemorrhage secondary to Glanzmann's syndrome

Characteristics of intraocular bleeding and its management in association with blood dyscrasias are discussed. We present a patient with massive bilateral choroidal hemorrhage secondary to Glanzmann's syndrome. Magnetic resonance imaging and ultrasonographic findings were ordered. During the clinical course, bilateral intravitreal hemorrhage and tractional retinal detachment occurred. Left pars plana vitrectomy was performed under general anaesthesia. The procedure was unsuccessful because of intraoperative uncontrolled bleeding.     

Rubella seroprevalence in women in the reproductive period, Mersin, Turkey

The aim of this study was to determine the rubella seroprevalence in women of reproductive age. This cross-sectional study was conducted on women aged 15-49 years. Serologic studies were performed by using the ELISA method. The number of women enrolled in the study was 607, the mean age was 30.7+/-9.3 years and 13.2% of the participants were living in the rural area. Rubella seroprevalence was 55.0%. This ratio was 77.5% in women living in the rural area (p<0.001). There were no statistically significant correlations between immunity to rubella and other socio-demographic characteristics. In conclusion, women in this age group are advised to have a single dose of rubella vaccination in order to avoid CRS before pregnancy.