The Use of Vital Dyes in Ocular Surgery

Vital dyes have advanced diagnosis and surgical technique in various specialties, including oncology, gastroenterology, and ophthalmology. In ocular surgery vital dyes are widely used in cataract and vitreoretinal surgery. Worldwide, intra-operative use of trypan blue during cataract surgery has enhanced visualization of the anterior capsule during capsulorrhexis, and patent blue has been recently licensed in Europe for cataract surgery. For chromovitrectomy, the vital dyes indocyanine green, infracyanine green, and brilliant blue stain the internal limiting membrane, and trypan blue and triamcinolone acetonide help visualize epiretinal membranes and vitreous, respectively. Intra-operative vital dyes are finding uses in corneal, glaucoma, orbit, strabismus, and conjunctival surgery. We provide a summary of current knowledge of the use of vital dyes in ocular surgery. We review the properties of dyes, techniques of application, indications, and complications in ocular surgery. Vital dyes represent an expanding area of research, and novel dyes deserve further investigation.     

Toxicity of lead on microorganisms: Interaction with protein content of culture medium

Lead is a significant environmental pollutant in Portugal, mainly as a consequence of its use as an antidetonant in gasoline. Due to the vast annual gas consumption, evidence of lead emission has been found in the air, soil, plants, and water. Concentrations of lead in Lisbon waste waters average 0.15 mg/L, with occasional levels reaching 1.5 mg/L. The biodegradability of these waste waters is affected by lead. To understand the interaction between lead toxicity and protein concentrations, a study was initiated using selected strains of Proteus mirabilis and Klebsiella pneumoniae and synthetic effluents. The toxicity of lead to bacteria was noted by an increase in the cell's metabolic activity, and a greater induction of ATP and RNA contents. However, bacterial replication was evidently uninhibited by the lead content in the test medium. While high peptone content in the growth medium caused an increase in the cell's biosynthesis, increased lead concentrations in the growth medium resulted in a substantial loss of metabolic product. This complex interaction was apparently responsible for lead's toxicity to bacteria.     

Anaglyphic three-dimensional stereoscopic printing: revival of an old method for anatomical and surgical teaching and reporting.

The authors describe how to use the three-dimensional (3D) anaglyphic method to produce stereoscopic prints for anatomical and surgical teaching and reports preparation by using currently available nonprofessional photographic and computer methods. As with any other method of producing stereoscopic images, the anaglyphic procedure is based on the superimposition of two slightly different images of the object to be reproduced, one seen more from a left-sided point of view and the other seen more from a right-sided point of view. The pictures are obtained using a single camera, which following the first shot can be slid along a special bar for the second shot, or by using two cameras affixed to a surgical microscope. After the images have been distinguished from each other by applying different complementary color dyes, the images are scanned and superimposed on each other with the aid of nonprofessional imaging-manipulation software used on a standard personal computer (PC), and are printed using a standard printer. To be seen stereoscopically, glasses with colored lenses, normally one red and one blue, have to be used. Stereoscopic 3D anaglyphic prints can be produced using standard photographic and PC equipment; after some training, the prints can be easily reproduced without significant cost and are particularly helpful to disclose the 3D character of anatomical structures.     

Local injection of BDNF producing mesenchymal stem cells increases neuronal survival and synaptic stability following ventral root avulsion

The present study proposed to graft mesenchymal stem cells (MSCs), which continuously produce BDNF, into the spinal cord ventral horn, after ventral root avulsion. Neurotrophin expression was naturally achieved by culturing MSCs in an undifferentiated state for at least 10 weeks. Lewis rats were subjected to unilateral avulsion of lumbar ventral roots, receiving 3 × 10⁵ cells injected through the lateral funiculus. Two weeks after surgery, the animals were sacrificed and neuronal survival, astroglial reaction and synaptic inputs within the motor nucleus analyzed. The results indicated that the MSCs treatment significantly rescued avulsed motoneurons. Such neuronal survival was related to in vivo mRNA up regulation as well as expression of BDNF and GDNF. Such increase was correlated to the preservation of synaptophysin- positive nerve terminals. Thus it was proposed that when maintained undifferentiated for a period of 10 weeks, MSCs may be used as a continuous source of BDNF, positively influencing neuronal survival and synaptic plasticity.     

Role of the α1-, and α2- and β-adrenoceptors of the median preoptic area on the water intake, renal excretion, and arterial pressure induced by ANG II

The present experiments were conducted to investigate the role of the α1-, α2- and β-adrenergic receptors of the median preoptic area (MnPO) on the water intake and urinary electrolyte excretion, elicited by central injections of angiotensin II (ANG II). Prazosin (an α1-adrenergic receptor antagonist) and yohimbine (an α2-adrenergic receptor antagonist) antagonized the water ingestion, Na⁺, K⁺, and urine excretion induced by ANG II. Administration of propranolol, a β-adrenergic receptor antagonist increased the Na⁺, K⁺, and urine excretion induced by ANG II. Previous treatment with prazosin and yohimbine reduced the pressor responses to ANG II. These results suggest that the adrenergic neurotransmission in the MnPO may actively participate in ANG II-induced dipsogenesis, natriuresis, kaliuresis, diuresis and pressor responses in a process that involves α1-, α2-, and β-adrenoceptors.     

Bone mineral density and osteoporosis among a predominantly Caucasian elderly population in the city of São Paulo, Brazil

This cross-sectional study covered 301 individuals over 70 years of age—207 women (W) and 94 men (M)—living in the city of São Paulo, Brazil. Our aims were to evaluate the prevalence of low bone mineral density (BMD) in this population and the possible factors that influence BMD. The subjects were submitted to a bone densitometry scan (DXA) to evaluate the BMD at lumbar spine (LS), femoral neck (FN), trochanter (T), total femur (TF) and total body composition. At the time, the participants filled in a questionnaire about lifestyle habits, diet and medical history, as well as having blood samples taken to check hormone and biochemical levels. Anthropometric parameters were measured. Osteopenia and osteoporosis were defined in accordance with the criteria suggested by the World Health Organization. In the different sites studied, the prevalence of osteopenia and osteoporosis varied, in men ranging 33.3–57.4% and 6.4–16.1%, respectively, and in women ranging 36.6–56.5% and 22.2–33.2%, respectively. Weight was the variable that most strongly correlated with BMD at the proximal femur in both sexes (men, r =0.44–0.52; women, r =0.48–0.52) and with BMD at LS in women ( r =0.44). Height was the parameter that best correlated with BMD at LS in men ( r =0.34). In men follicle-stimulating hormone, growth hormone and glycemia correlated with BMD at T and TF, while plasma albumin only correlated with BMD at T. In women glycemia correlated with BMD at LS, and follicle-stimulating hormone correlated with BMD at FN, T and TF. In conclusion, we found a high prevalence of osteopenia and osteoporosis in this population, with weight being the best predictor of BMD. The prevalence of osteoporosis and osteopenia at FN was as high in men as that observed in women.     

Posterior atlantoaxial arthrodesis. A simplified method

A simplified method of posterior atlantoaxial arthrodesis allowing immediate stabilization and mobilization is described. This method of fixation has been used since 1984 in 33 cases, with the indications being nonunion of odontoid peg fractures, atlantoaxial dislocation, and other traumatic conditions about the axis. A solid fusion was noted in all 33 patients by 3 months postsurgery, and the complication rate was minimal. This method of atlantoaxial arthrodesis is simple, allows immediate mobilization, controls rotation and lateral bending, and is inexpensive.     

Patterns of Primary Care Use Prior to a First Diagnosis of Nonaffective Psychotic Disorder in Ontario,Canada: Modèles d’utilisation des soins de première ligne avant un premier diagnostic de trouble psychotique non affectif en Ontario,Canada

Background:Many people experience early signs and symptoms before the onset of psychotic disorder, suggesting that there may be help-seeking prior to first diagnosis. The family physician has been found to play a key role in pathways to care. This study examined patterns of primary care use preceding a first diagnosis of psychotic disorder.Methods:We used health administrative data from Ontario (Canada) to construct a population-based retrospective cohort. We investigated patterns of primary care use, including frequency and timing of contacts, in the 6 years prior to a first diagnosis of psychosis, relative to a general population comparison group matched on age, sex, geographic area, and index date. We used latent class growth modeling to identify distinct trajectories of primary care service use, and associated factors, preceding the first diagnosis.Results:People with early psychosis contacted primary care over twice as frequently in the 6 years preceding first diagnosis (RR = 2.22; 95% CI, = 2.19 to 2.25), relative to the general population, with a sharp increase in contacts 10 months prior to diagnosis. They had higher contact frequency across nearly all diagnostic codes, including mental health, physical health, and preventative health. We identified 3 distinct service use trajectories: low-, medium-, and high-increasing usage.Discussion:We found elevated patterns of primary care service use prior to first diagnosis of psychotic disorder, suggesting that initiatives to support family physicians in their role on the pathway to care are warranted. Earlier intervention has implications for improved social, educational, and professional development in young people with first-episode psychosis.     

Primary carnitine deficiency

Carnitine deficiency can be defined as a decrease of intracellular carnitine, leading to an accumulation of acyl-CoA esters and an inhibition of acyl-transport via the mitochondrial inner membrane. This may cause disease by the following processes. A. Inhibition of the mitochondrial oxidation of long-chain fatty acids during fasting causes heart or liver failure. The latter may cause encephalopathy by hypoketonaemia, hypoglycaemia and hyperammonaemia. B. Increased acyl-CoA esters inhibit many enzymes and carriers. Long-chain acyl-CoA affects mitochondrial oxidative phosphorylation at the adenine nucleotide carrier, and also inhibits other mitochondrial enzymes such as glutamate dehydrogenase, carnitine acetyltransferase and NAD(P) transhydrogenase. C. Accumulation of triacylglycerols in organs increases stress susceptibility by an exaggerated response to hormonal stimuli. D. Decreased mitochondrial acetyl-export lowers acetylcholine synthesis in the nervous system. Primary carnitine deficiency can be defined as a genetic defect in the transport or biosynthesis of carnitine. Until now only defects at the level of carnitine transport have been discovered. The most severe form of primary carnitine deficiency is the consequence of a lesion of the carnitine transport protein in the brush border membrane of the renal tubules. This defect causes cardiomyopathy or hepatic encephalopathy usually in combination with skeletal myopathy. In a patient with cardiomyopathy and without myopathy, we found that carnitine transport at the level of the small intestinal epithelial brush border was also inhibited. The patient was cured by carnitine supplementation. Muscle carnitine increased, but remained too low. This suggests that carnitine transport in muscle is also inhibited. Carnitine transport in fibroblasts was normal, which disagrees with literature reports for similar patients.     

Ocular jellyfish stings.

BACKGROUND: Corneal stings from the sea nettle (Chrysaora quinquecirrha) indigenous to the Chesapeake Bay are usually painful but self-limited injuries, with resolution in 24 to 48 hours. METHODS: Five patients who developed unusually severe and prolonged iritis and intraocular pressure elevation after receiving corneal sea nettle stings were followed for 2 to 4 years. RESULTS: Decreased visual acuity, iritis, and increased intraocular pressure (32 to 48 mmHg) were noted in all cases. Iritis responded to topical corticosteroids and resolved within 8 weeks. Elevated intraocular pressure responded to topical beta blockers and oral carbonic anhydrase inhibitors. Mydriasis (4 of 5 cases), decreased accommodation (2 of 5 cases), peripheral anterior synechiae (2 of 5 cases), and iris transillumination defects (3 of 5 cases) also were noted. Mydriasis and decreased accommodation persisted for 5 months in 1 case and for more than 2 years in another. One patient has chronic unilateral glaucoma. Visual acuity returned to normal in all cases. CONCLUSIONS: The precise relationship between sea nettle venom and the observed clinical responses is not known. Corneal jellyfish stings usually produce a brief and self-limited reaction, but they do have the potential for long-term sequelae.