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Background: The coexistence of cataract and age related macular degeneration (AMD) is not unusual, especially in the very elderly. The outcome of cataract surgery in these cases depends on the effect of AMD on vision. In this study the authors have compared the outcome of cataract patients with AMD to that of cataract patients with no vision threatening ocular comorbidity, and analysed possible predictors of good or poor outcome. Methods: An observational prospective study on consecutive cases operated for cataract during 1 month at six surgical departments affiliated to the Swedish National Cataract Register (NCR). Data were collected according to the protocol of NCR and subjects completed the Catquest questionnaire before and 6 months after surgery. 90 subjects with AMD were compared to 335 subjects with no sight threatening ocular comorbidity. Results: Difficulties in performing various daily life activities improved significantly for AMD subjects after surgery (p<0.001, Wilcoxon signed rank test). Satisfaction with vision also improved significantly after surgery (p<0.001, Wilcoxon signed rank test). Activity level and independence were unchanged. Subjects with no ocular comorbidity had a still better outcome. The most important variable related to a good self assessed functional outcome was postoperative visual acuity irrespective of the presence of AMD. AMD subjects scheduled for second eye surgery and AMD subjects dissatisfied with their vision before surgery had a poorer outcome. Conclusion: Subjects with various stages of dry AMD and cataract improved their self assessed visual function and satisfaction with vision significantly after cataract extraction. [ABSTRACT FROM AUTHOR]

Background: Endogenous hyaluronan has been found in different tissues in the normal and traumatized eye. However, the main source, the biological aspects and the full potential role of hyloronan are still unclear. Methods: Hyaluronan production was studied both in organ culture and in vivo , using a double-label protocol with [35S]sulfate and [3H]glucosamine. Results: [3H]glucosamine and [35S]sulfate were incorporated into hyaluronan and sulfated glycosaminoglycans in normal and in traumatized iris tissue in organ culture and in vivo . There was low relative hyaluronan synthesis in vivo, only 2% of total incorporated [3H]glucosamine in normal irides. Increased relative incorporation of [3H]glucosamine into hyaluronan was seen after operative trauma to iris tissue both in vivo and in vitro. Conclusion: Our findings demonstrate synthesis of hyaluronan by normal and traumatized iris. The iris seems to be the most important source of aqueous hyaluronan. [ABSTRACT FROM AUTHOR]

Adult rats with unilateral 6-hydroxydopamine lesions of the nigrostriatal pathway were tested for amphetamine-induced rotational asymmetry. In animals with functional deficits a fetal mesencephalic transplant was placed intracranially over the superior colliculus within the caudal end of a 2- to 3-cm-long heterologous sciatic nerve segment laid longitudinally on the skull. Two months later the rostral tip of the peripheral nerve graft was cut and inserted through a burr-hole into the denervated striatum. Animals were tested monthly for 5 months for rotational asymmetry and selected rats were sacrificed for histochemical examination. It was shown that the use of a peripheral nerve segment as a bridge between a distant neuronal transplant and a selected region of the adult host brain resulted in the growth of monoaminergic axons into the denervated striatum from the extracerebrally located grafted neurons. The nerve bridge was cut extracranially in rats whose rotational asymmetry had decreased towards normal levels to determine if this behaviour was dependent on axons reaching the striatum through the graft. Each of these animals exhibited an increase in rotational asymmetry one and three weeks after the transection of the nerve. These anatomical and functional observations suggest that the decrease in rotational asymmetry observed in these animals is related to the growth of long axons from the implanted mesencephalic neurons into the denervated host's striatum which traversed the entire peripheral nerve segment. [ABSTRACT FROM AUTHOR]

Transection of the septo-hippocampal connections through fimbria-fornix damage in the rat results in profound hippocampal cholinergic deafferentation, and, when applied bilaterally, leads to severe and long-lasting impairments in learning and memory. Previous studies have shown that intrahippocampal septal grafts can reestablish a new cholinergic innervation in the inititally denervated hippocampal formation and at least partly compensate for the lesion-induced learning impairments in fimbria-fornix lesioned rats. The purpose of the present study was to determine the magnitude of lesion-induced alterations in cerebral function as reflected in local glucose use measured by (C)-2-deoxyglucose (2-DG) autoradiography, and the degree to which this index of functional activity could be normalized following reinnervation from transplants of fetal cerebral tissue from the primordial septal region. Six months after unilateral fimbriafornix transection the rate of glucose utilization was reduced markedly throughout the ipsilateral hippocampus when compared to the intact contralateral side, while in the neocortex only the cingulate cortex showed long-lasting reductions in glucose use. Rats that received a transplant of fetal septal-diagonal band tissue at the time of fimbria-fornix transection, and were sacrificed 6 months later, displayed significantly greater glucose utilization in the ipsilateral hippocampus and cingulate cortex than was measured in these areas in rats with lesion alone. The recovery in glucose use was paralleled by a significant increase in acetylcholinesterase (AChE) staining in several areas of the ipsilateral hippocampal formation and cingulate cortex. This index of graft-induced cholinergic reinnervation was, moreover, significantly correlated with the rate of glucose use. Thus, in the fimbria-fornix transected animals the magnitude of glucose depression correlated with the extent of reduction in AChE staining, and in the grafted animals the degree of normalization of glucose use was correlated with the graft-induced increase in AChE-staining density. These results thus indicate that the 2-DG autoradiographic technique can provide a unique opportunity to map both altered functional activity in localized areas of the brain following specific lesions and the extent to which transplant-derived reinnervation of the host may induce a return to normal functional levels in the target site. [ABSTRACT FROM AUTHOR]

Transplantation of human brain tumours into the brain of normal laboratory animals is still considered to be unsatisfactory by many researchers, despite the fact that the brain is considered an immunologically privileged site. We present in this paper a model of Xenotransplantation fo human astrocytomas grade III-IV into the brain of normal, adult Sprague-Dawley rats with good take rates, i.e. takes in two thirds of the animals, half of these with large, infiltrating tumours. The transplants are placed using a microsurgical technique in the vessel-rich choroidal fissure in the host brain from where rapid vascularization occurs. The technique has previously been used for CNS-regeneration studies. This model should provide an excellent opportunity to study human malignant astrocytomas in a milieu as natural as possible. [ABSTRACT FROM AUTHOR]

AIMS--Cataract surgery has at times been said to correlate with an increased death risk. We have therefore analysed the standardised death ratio in a population based cohort of patients that had undergone cataract surgery. METHODS--Data for all patients undergoing cataract surgery from 1986 up to and including 1990 in the Lund Health Care District were prospectively recorded, and 5120 were retrieved for analysis. Death dates and primary death diagnoses for each patient were obtained from the Swedish Bureau of Census up to and including 1991. Standardised mortality ratios were calculated for all patients, subdivided into a number of categories: inpatients, outpatients, sex, age < 75 years, age > or = 75 years, patients with heart and circulatory diseases, with malignant tumours, and with diabetes. The cut off age was set at 74 because this divided the patients into two approximately equal groups. Using time dependent survival regression, the relative risk for dying were estimated for sex, age, and for postoperative YAG laser capsulotomy, and also for diabetic patients and patients with rheumatoid arthritis. RESULTS--Inpatients almost always show an increased standardised mortality ratio compared with outpatients. Young patients and diabetic patients also showed an increased standardised mortality ratio, compared with the normal population, but not older patients, who constitute the majority. Cardiovascular death diagnoses were overrepresented among the young. CONCLUSIONS--Cataract surgery is correlated with an increased standardised mortality ratio only in young patients and in patients with certain complicating diseases like diabetes and cardiovascular diseases. [ABSTRACT FROM PUBLISHER]

The usefulness of three neurotoxic dihydroxytryptamines - 5,6-dihydroxytryptamine, 5,7-dihydroxytryptamine and 4,5-dihydroxytryptamine - for fluorescence microscopical tracing and localized lesioning of central indolamine-containing axon bundles has been studied in the rat brain. The lesions produced by intraventricularly or intracerebrally administered dihydroxytryptamines were found to be much superior to mechanical or electrolytic lesions in producing extensive accumulations of fluorescence in the indolamine axon pathways. This greatly improves the possibilities for tracing of the normally non-fluorescent or weakly fluorescent indolamine axons from their cells of origin for long distances through the main fibre bundles and their branches. Much new information concerning the anatomy of the indolamine neuron systems is obtained with this technique, and some preliminary observations are presented. The efficiency of local, intracerebral injections of small amounts of dihydroxytryptamines for regional denervations in the CNS was also tested. It was found that local injections of 4 μg of either of the three compounds into the ventromedial tegmentum and into the grey matter of the spinal cord produced extensive and probably rather selective damage to the ascending and descending indolamine fibre tracts and - although to a lesser and variable extent - the noradrenaline and dopamine systems. The denervating effects of the tegmental and the spinal cord injections were with respect to the serotonin-containing neurons comparable to those obtained by others after large lesions that destroy almost the entire midbrain raphe region, and after total transections of the spinal cord, respectively. The characteristics and the specificity of the dihydroxytryptamine-induced lesions are discussed. [ABSTRACT FROM AUTHOR]

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Purpose To elucidate the pattern of donor and recipient endothelial cell population in transplanted human corneas and investigate factors impacting this mosaic. Methods 36 corneal grafts were collected from recipients of opposite sex to the donor, at the time of re‐transplantation. An endothelial sheet was harvested from each graft, and labeled by fluorescent in situ hybridization of the sex chromosomes, to identify cells as donor or recipient‐derived. Images of the graft endothelium were assembled to depict the pattern of cell population of the graft, and the proportion of donor cells present was estimated. Results Endothelial cells of donor origin were found in 26 of 36 grafts, persisting up to 26 years after transplantation. The proportion of donor endothelial cells in the graft was not significantly correlated with postoperative time (P = 0.19). Endothelial images indicated a highly variable pattern of recipient cell repopulation of the graft. A tendency towards donor cell retention in transparent, successful grafts was noted; however, this feature alone was not a reliable indicator of long‐term graft transparency. Recent in‐vivo optical coherence tomography studies of transplanted corneas indicate a possible mechanism impacting the donor and recipient cell patterns observed on the endothelial surface. Conclusion Two‐dimensional imaging of the corneal graft endothelium revealed a variable pattern and extent of donor and recipient cell population, indicating the highly dynamic nature of the corneal endothelium after transplantation. [ABSTRACT FROM AUTHOR]