Effectiveness of topical taurolidine versus ciprofloxacin, ofloxacin, and fortified cefazolin in a rabbit Staphylococcus aureus keratitis model

PURPOSE: Taurolidine is a broad-spectrum, non antibiotic antimicrobial agent, not previously tested against the common causes of bacterial keratitis. This study, employing an experimental rabbit model of Staphylococcus aureus keratitis, investigated the effectiveness of topical taurolidine in reducing the number of bacteria, and its effectiveness was compared with topical ciprofloxacin, ofloxacin, and 5% cefazolin. METHODS: The right corneas of all rabbits were intrastromally injected with 100 colony-forming units of Staphylococcus aureus ATCC strain 25923. The animals were divided into the following seven groups: Group 1 (6 rabbits) received taurolidine, group 2 (6 rabbits) received ciprofloxacin, group 3 (6 rabbits) received ofloxacin, group 4 (6 rabbits)received cefazolin, group 5 (5 rabbits) received polyvinylpyrrolidone (vehicle),group 6 (4 rabbits) received sterile water, and group 7 (4 rabbits) was left un-treated (control group). The eyes were topically treated every 30 min with the above-mentioned substances from 4 to 9 h postinjection. One hour after the last drop administration (at 10 h postinjection), signs of inflammation were scored in a masked fashion by slit-lamp examination. Then, their corneas were processed. The number of colony-forming units (cfu) per cornea in all eyes was also determined. RESULTS: All antimicrobial (taurolidine, ciprofloxacin, ofloxacin, and cefazolin) treatments significantly reduced cfu numbers and slit-lamp examination scores compared with untreated eyes, eyes that received the vehicle, or eyes with sterile water (all p values <0.05). Regarding cfu numbers, although taurolidine therapy was significantly less effective than ciprofloxacin or ofloxacin,there was no significant difference between taurolidine and cefazolin groups.However, taurolidine had similar clinical examination scores with the other antimicrobials, while it had lower scores than the vehicle, sterile water, or un-treated eyes. CONCLUSIONS: The results obtained in this study suggest that topicaltaurolidine is an effective, novel ocular chemotherapeutic agent for the therapy of rabbit experimental Staphylococcus aureus keratitis. This drug may be a useful and promising ocular antimicrobial.     

Proton magnetic resonance spectroscopy of normal appearing white matter in familial and sporadic multiple sclerosis

Objective To assess metabolite levels in normal–appearing white matter in sporadic and familial multiple sclerosis (MS). Methods Using H–MRS and applying one voxel measure we assessed NAA/Cho,NAA/Cr and Cho/Cr ratios in 26 patients with sporadic and in 25 with familial MS and compared them with healthy subjects. Results In both MS groups NAA/Cho and NAA/Cr ratio were significantly lower than in healthy individuals whereas Cho/Cr ratio was higher in MS patients. In sporadic MS patients NAA/Cho and NAA/Cr ratios were lower, although not significantly, than in familial cases. The Cho/Cr ratio was similar in both MS groups. Conclusion These results suggest that subtle differences in H–MRS measures corresponding to axonal rather than to myelin pathology might occur in sporadic and familial MS.     

Neural correlates of eye-gaze detection in young children with autism

Various reports have demonstrated difficulties in eye-gaze processing in older children and adults with autism. However, little is known about the neural or developmental origin of such difficulties. In the present study, we used high-density Event-Related Potentials (HD-ERPs) to record the neural correlates of gaze processing in young children with autism, and their age-matched controls. In addition, to determine normal gaze processing development we also tested a non-autism adult group. The data obtained from the children with autism resembled that previously observed in typical 4-month old infants. In contrast, the control group showed the same pattern as typical adults. These findings suggest that the neural correlates of gaze direction processing may be delayed in young children with autism.     

The incidence of recurrence and hypothyroidism after radioiodine treatment in patients with hyperthyroidism in Trakya, a mild iodine deficiency area, during the period 1991–2003

Objective  The purpose of this retrospective study was to evaluate the incidence of recurrence and the success of radioiodine treatment (RIT) in the Trakya region of Turkey, an area with mild iodine deficiency, and to compare the effect of dose regimen selection (fixed (FD) or calculated dose (CD)) on treatment success. Material and Methods  The study sample included 148 patients (40 male, median age 50) treated with radioiodine between the years 1991-2003. Patients were categorized into three diagnostic groups: Graves’ disease (GD) (n = 65), solitary toxic adenoma (TA) (n = 29), and toxic multinodular hyperthyroidism (TMH) (n = 54), and each divided into two subgroups according to treatment method; the first group was treated with a FD of 370 MBq (10 mCi), and the second with CD. Results  The largest group was GD (44%), followed by TMH (36%). Median duration of follow-up was 28 months (range 6-147). FD was given to 52.7% of all patients and CD was given to 47.3%. There was a partial difference in the dose regimen between all groups, but did not reach statistically significant levels (FD vs. CD: 65%–35%; 38%–62%; 46%–54%; GD, TA, TMH respectively, p > 0.05). Total cure rate in FD and CD was 46 (59%) and 37 (52.9%), respectively. The rates of hypothyroidism for GD, TA, and TMH groups were 28 (43.1%), 6 (20.7%) and 16 (29.6%), respectively. The incidence of hypothyroidism did not vary significantly between any groups (p > 0.05). At the end of the follow-up period, a total of 104 patients (70.3%) were treated successfully. There was no significant difference in the cure rate between any groups (p > 0.05). Conclusions  The treatment success in all groups and subgroups did not differ significantly between FD and CD. Our lower cure rate than in previous studies may be related to iodine deficiency. Higher doses of radioiodine may be required to increase final treatment success in endemic goiter areas. If this true, dosimetry and calculated dose regimen would be required in all groups of patients instead of an FD concept. However, our findings should be verified in larger series of patients, with longer follow-up period, and urinary iodine concentration measurements. This work was presented in part at the 5th International Congress of Nuclear Oncology & 15th National Congress of Nuclear Society of Nuclear Medicine, May 1-5, 2002, Kusadasi, Turkey.     

Gray scale and power Doppler US in the preoperative evaluation of axillary metastases in breast cancer patients with no palpable lymph nodes

The purpose of this study is to evaluate the accuracy of gray scale and Doppler US findings in the detection of axillary metastases in breast cancer patients with no palpable lymph nodes. One-hundred and ninety-eight lymph nodes detected in 83 women were evaluated. The size and longitudinal/transverse axis ratios of each node were documented. Absence of echogenic hilum, asymmetrical cortical thickening, and presence of peripheral flow were prospectively considered signs of malignancy. Histopathologically, there were 93 malignant and 105 benign nodes. The above criteria and a low longitudinal-transverse axis ratio were statistically significant for malignancy. In lymph nodes smaller than 1 cm, only asymmetric cortical thickening and presence of peripheral flow were significant. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of US were 86.49, 93.62, 91.43, 89.8 and 90.48%, respectively. In conclusion, US is successful and reliable in the determination of axillary metastatic involvement in nonpalpable and small lymph nodes. Inclusion of axillary US in the preoperative diagnostic evaluation would be complimentary to sentinel node biopsy, and also could eliminate the need for it in patients with positive US results, after confirmation with biopsy.     

Secondary involvement of breast with non-Hodgkin's lymphoma in a paediatric patient presenting as bilateral breast masses

We report a paediatric case of non-Hodgkin's lymphoma with secondary breast involvement. On US exam there were bilateral multiple well-defined masses. Contrast-enhanced thorax CT demonstrated the breast lesions as well as enhancing masses. To our knowledge, this type of lymphomatous breast involvement in a child is rare and its CT features are very rarely demonstrated. Received: 16 October 1998; Revision received: 21 April 1999; Accepted: 28 May 1999     

Functional changes after prenatal opiate exposure related to opiate receptors' regulated alterations in cholinergic innervation

Opioid drugs act primarily on the opiate receptors; they also exert their effect on other innervations resulting in non-opioidergic behavioural deficits. Similarly, opioid neurobehavioural teratogenicity is attested in numerous behaviours and neural processes which hinder the research on the mechanisms involved. Therefore, in order to be able to ascertain the mechanism we have established an animal (mouse) model for the teratogenicity induced by opioid abuse, which focused on behaviours related to specific brain area and innervation. Diacetylmorphine (heroin) and not morphine was applied because heroin exerts a unique action, distinguished from that of morphine. Pregnant mice were exposed to heroin (10 mg/kg per day) and the offspring were tested for behavioural deficits and biochemical alterations related to the septohippocampal cholinergic innervation. Some studies employing the chick embryo were concomitantly added as a control for the confounding indirect variables. Prenatal exposure to heroin in mice induced global hyperactivation both pre- and post-synaptic along the septohippocampal cholinergic innervation, including basal protein kinase C (PKC) activity accompanied by a desensitization of PKC activity in response to cholinergic agonist. Functionally, the heroin-exposed offspring displayed deficits in hippocampus-related behaviours, suggesting deficits in the net output of the septohippocampal cholinergic innervation. Grafting of cholinergic cells to the impaired hippocampus reversed both pre- and post-synaptic hyperactivity, resensitized PKC activity, and restored the associated behaviours to normality. Consistently, correlation studies point to the relative importance of PKC to the behavioural deficits. The chick model, which dealt with imprinting related to a different brain region, confirmed that the effect of heroin is direct. Taken together with studies by others on the effect of prenatal exposure to opioids on the opioidergic innervation and with what is known on the opioid regulation of the cholinergic innervation, it appears that heroin exerts its neuroteratogenicity by inducing alterations in the opioidergic innervation, which by means of its regulatory action, attenuates the functional output of the cholinergic innervation. In our model, there was hyperactivity mostly of the post-synaptic components of the cholinergic innervation. However, the net cholinergic output is decreased because PKC is desensitized to the effect of the cholinergic agonist, and this is further evidenced by the extensive deficits in the related behaviours.