Optical coherence tomography imaging of the basal ganglia: feasibility and brief review

Optical coherence tomography (OCT) is a promising medical imaging technique that uses light to capture real-time cross-sectional images from biological tissues in micrometer resolution. Commercially available optical coherence tomography systems are employed in diverse applications, including art conservation and diagnostic medicine, notably in cardiology and ophthalmology. Application of this technology in the brain may enable distinction between white matter and gray matter, and obtainment of detailed images from within the encephalon. We present, herein, the in vivo implementation of OCT imaging in the rat brain striatum. For this, two male 60-day-old rats (Rattus norvegicus, Albinus variation, Wistar) were stereotactically implanted with guide cannulas into the striatum to guide a 2.7-French diameter high-definition OCT imaging catheter (Dragonfly™, St. Jude Medical, USA). Obtained images were compared with corresponding histologically stained sections to collect imaging samples. A brief analysis of OCT technology and its current applications is also reported, as well as intra-cerebral OCT feasibility on brain mapping during neurosurgical procedures.

Hyperhomocystinemia in patients with coronary artery disease

Hyperhomocystinemia has been related to an increased risk of cardiovascular disease in several studies. The C677T polymorphism for the gene that encodes the methylenetetrahydrofolate reductase enzyme (MTHFR) and low plasma folate levels are common causes of hyperhomocystinemia. Due to differences in nutritional patterns and genetic background among different countries, we evaluated the role of hyperhomocystinemia as a coronary artery disease (CAD) risk factor in a Brazilian population. The relation between homocysteine (Hcy) and the extent of CAD, measured by an angiographic score, was determined. A total of 236 patients referred for coronary angiography for clinical reasons were included. CAD was found in 148 (62.7 percent) patients and 88 subjects had normal or near normal arteries. Patients with CAD had higher Hcy levels [mean (SD)] than those without disease (14 (6.8) vs 12.5 (4.0) æM; P = 0.04). Hyperhomocystinemia (Hcy >17.8 æM) prevalence was higher in the CAD group: 31.1 vs 12.2 percent (P = 0.01). After adjustment for major risk factors, we found an independent association between hyperhomocystinemia and CAD (OR = 2.48; 95 percent CI = 1.02-6.14). Patients with a more advanced coronary score had a higher frequency of hyperhomocystinemia and tended to have higher mean Hcy levels. An inverse relation between plasma folate and Hcy levels was found (r = -0.14; P = 0.04). Individuals with the MTHFR C677T polymorphism had a higher prevalence of hyperhomocystinemia than those without the mutated allele. We conclude that hyperhomocystinemia is independently associated with CAD, with a positive association between Hcy level and disease severity.

Síndrome do intestino curto: aspectos fisiopatológicos, clínicos e suporte nutricional de longa duraçäo / Short bowel syndrome: physiopathological and clinical aspects, and long-term nutritional support

Os pacientes com Síndrome do Intestino Curto (SIC) necessitam de suporte nutricional parenteral, sem o que a taxa de mortalidade é superior a 80 por cento. A unidade Metabólica do Hospital de Clínicas da Faculdade de Medicina de Ribeirao Preto mantém programa de suporte nutricional parenteral em regime ambulatorial para o paciente com SIC, estabelecido de acordo com a necessidade individual de cada paciente, o que é determinado pela avaliaçao periódica do estado nutricional por meio de critérios clínicos, dietéticos, antropométricos e bioquímicos. Este artigo discute os aspectos fisiopatológicos e clínicos da SIC, bem como a conduta do suporte nutricional de longa duraçao empregada nos pacientes tratados na Unidade Metabólica do Hospital de Clínicas da Faculdade de Medicina de Ribeirao Preto.