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Background Over 300,000 cataract operations are performed in Poland every year, and the most common, late complication of cataract removal surgery is posterior capsule opacification (PCO). The risk of PCO depends on the lens material. Hydrophobic acrylic lenses cause PCO less frequently as lymphatic endothelial cells show lower affinity for the surface of the lens made of silicone. The objective of this study is to assess the economic impact of using hydrophobic acrylic lenses compared to using hydrophilic acrylic lenses for cataract treatment in the Polish inpatient and outpatient settings. Methods A budget impact analysis (BIA) compared the economic outcomes associated with using hydrophobic acrylic lenses versus using hydrophilic lenses for patients undergoing cataract surgery. The BIA predicted annual expenses in the following scenarios: performing Nd:YAG to treat PCO within 2 and 3 years after implantation of hydrophobic or hydrophilic acrylic lenses for different lens structure. Data used to assess the frequency of PCO was determined in systematic literature review. Costs of current and predicted interventions were estimated based on average data from 19 Polish hospitals. Prices of health services were taken from official public tariff lists. Results The use of a hydrophobic lens significantly limits the number of complications after cataract surgery relative to a hydrophilic lens. As hydrophobic lenses have a higher unit price their use increases the cost of treatment which currently is not reflected by adequate difference in price of the service. Total annual National Health Fund (NHF) expenses for 3-year follow-up model range from 139.1 million EUR to 143.1 million EUR depending on the lens structure, due to the cost of complications. Conclusions BIA indicates the possibility of introducing surcharge for the use of hydrophobic lenses, which could increase the frequency of their use and reduce the number of complications after cataract surgery. It was estimated that total NHF expenses reach the minimum value for the surcharge at the level of 9 EUR. The surcharge of 14 EUR is the maximum value that does not increase the initial NHF expenses.

Introduction: In vitro experiments have demonstrated that preconditioning primary neuronal cultures by temporary application of NMDA receptor antagonists induces long-term tolerance against lethal insults. In the present study we tested whether similar effects also occur in brain submitted to ischemia in vivo and whether the potential benefit outweighs the danger of enhancing the constitutive apoptosis in the developing brain. Material and methods: Memantine in pharmacologically relevant doses of 5 mg/kg or (+)MK-801 (3 mg/kg) was administered i.p. 24, 48, 72 and 96 h before 3-min global forebrain ischemia in adult Mongolian gerbils or prior to hypoxia/ ischemia in 7-day-old rats. Neuronal loss in the hippocampal CA1 in gerbils or weight deficit of the ischemic hemispheres in the rat pups was evaluated after 14 days. Also, the number of apoptotic neurons in the immature rat brain was evaluated. Results: In gerbils only the application of (+)MK-801 24 h before ischemia resulted in significant prevention of the loss of pyramidal neurons. In rat pups administration of (+)MK-801 at all studied times before hypoxia-ischemia, or pretreatment with memantine or with hypoxia taken as a positive control 48 to 92 h before the insult, significantly reduced brain damage. Both NMDA receptor antagonists equally reduced the number of apoptotic neurons after hypoxia-ischemia, while (+)MK-801-evoked potentiation of constitutive apoptosis greatly exceeded the effect of memantine. Conclusions: We ascribe neuroprotection induced in the immature rats by the pretreatment with both NMDA receptor antagonists 48 to 92 h before hypoxia-ischemia to tolerance evoked by preconditioning, while the neuroprotective effect of (+)MK-801 applied 24 h before the insults may be attributed to direct consequences of the inhibition of NMDA receptors. This is the first report demonstrating the phenomenon of inducing tolerance against hypoxia-ischemia in vivo in developing rat brain by preconditioning with NMDA receptor antagonists.

Perinatal brain insult mostly resulting from hypoxia-ischemia (H-I) often brings lifelong permanent disability, which has a major impact on the life of individuals and their families. The lack of progress in clinically-applicable neuroprotective strategies for birth asphyxia has led to an increasing interest in alternative methods of therapy, including induction of brain tolerance by pre- and particularly postconditioning. Hypoxic postconditioning represents a promising strategy for preventing ischemic brain damage. The aim of this study was to investigate the potential neuroprotective effect of hypobaric hypoxia (HH) postconditioning applied to 7-day old rats after H-I insult. The mild hypobaric conditions (0.47 atm) used in this study imitate an altitude of 5,000 m. We show that application of mild hypobaric hypoxia at relatively short time intervals (1-6 h) after H-I, repeated for two following days leads to significant neuroprotection, manifested by a reduction in weight loss of the ipsilateral hemisphere observed 14 days after H-I. HH postconditioning results in decrease in reactive oxygen species level observed in all experimental groups. The increase in superoxide dismutase activity observed after H-I is additionally enhanced by HH postconditioning applied 1 h after H-I. The increase observed 3 and 6 h after H-I was not statistically significant. Postconditioning with HH suppresses the glutathione concentration decrease evoked by H-I and increased glutathione peroxidase activity and this effect is not dependent on the time of postconditioning initiation. HH postconditioning had no effect on catalase activity. We show for the first time that HH postconditioning reduces brain damage resulting from H-I in immature rats and that the mechanism potentially involved in this effect is related to antioxidant defense mechanisms of immature brain.

The aim of this study was to establish the antagonistic effects of 1-methyl-1,2,3,4-tetrahydroisoquinoline (1MeTIQ) on NMDA receptors and its neuroprotective abilities on primary cultures of rat cerebellar granule cells exposed for 30 min to 250 or 100 μM glutamate. Neuronal viability was tested after 24 h with propidium iodide or calcein/ethidium homodimer-1 staining. The neuroprotective potential of 100, 250 or 500 μM 1MeTIQ was compared with established uncompetitive NMDA receptor antagonists, 0.5 Μm MK-801, or 5 μMmemantine. These substances were applied for 30 min either together with glutamate, 24 or 48 h before glutamate, or 0.5 h, 1 h and 3 h after exposure to the excitotoxin. The results demonstrated that MK-801, memantine and 500 μM 1MeTIQ induced an almost complete neuroprotection when co-applied with glutamate, but lower concentrations of 1MeTIQ were slightly less effective. Similar effects for 1MeTIQ and the established NMDA receptor antagonists were observed in the pretreatment experiments, even with a 48-h lag between the application of the tested substances and the excitotoxic challenge. In the post-treatment experiments, MK-801 and memantine and 500 μM 1MeTIQ applied up to 3 h after the exposure to glutamate significantly reduced the excitotoxic lesion, but 1MeTIQ in lower concentrations was ineffective. These results indicate that 1MeTIQ shares neuroprotective abilities with established uncompetitive NMDA receptor antagonists, which suggests that its inhibitory effect on NMDA receptors plays a key role in its anti-excitotoxic activity. Moreover, our data disclose a new mechanism of 1MeTIQ-evoked neuroprotection based on the induction of neuronal tolerance to excitotoxicity.

In the present study, we examined the effects of negative and positive allosteric modulators of metabotropic glutamate receptor 5 (mGluR5), fenobam and ADX47273, respectively, on brain damage induced by hypoxia-ischemia (H-I) in 7-day-old rats. The test drugs were administered intraperitoneally 10 min after H-I. Rectal body temperature was measured for 2.5 h after the insult. The number of apoptotic neurons in the immature rat brain was evaluated after 24 h. The wet weight of both hemispheres was determined 14 days after H-I, and its loss was used as an indicator of brain damage. In the vehicle-treated groups, H-I reduced the weight of the ipsilateral (ischemic) hemisphere by approximately 33% and sixfold increased the number of apoptotic cells in the cortex. Fenobam (10 mg/kg) and ADX47273 (5, 10, and 30 mg/kg) had no significant effect on brain damage, although application of fenobam at this dose significantly reduced the number of apoptotic cells. In contrast, fenobam (20 mg/kg) potentiated ischemic brain damage to 57.4% and had no effect on H-I-induced apoptosis. In all of the experimental groups, we detected no significant changes in the weight of the contralateral (control) hemisphere or the rectal temperature. In conclusion, in 7-day-old rats, the bidirectional modulation of mGluR5 by fenobam (10 mg/kg) and ADX47273 (all doses tested) did not result in significant changes in H-I-evoked brain damage, supporting our previous data indicating that also the antagonists of mGluR5 MPEP and MTEP, which reduce neuronal lesions in adult animals submitted to brain ischemia, were ineffective in 7-day-old rat pups.