Representation of spatial frequency and orientation in the visual cortex

Knowledge of the response of the primary visual cortex to the various spatial frequencies and orientations in the visual scene should help us understand the principles by which the brain recognizes patterns. Current information about the cortical layout of spatial frequency response is still incomplete because of difficulties in recording and interpreting adequate data. Here, we report results from a study of the cat primary visual cortex in which we employed a new image-analysis method that allows improved separation of signal from noise and that we used to examine the neurooptical response of the primary visual cortex to drifting sine gratings over a range of orientations and spatial frequencies. We found that (i) the optical responses to all orientations and spatial frequencies were well approximated by weighted sums of only two pairs of basis pictures, one pair for orientation and a different pair for spatial frequency; (ii) the weightings of the two pictures in each pair were approximately in quadrature (1/4 cycle apart); and (iii) our spatial frequency data revealed a cortical map that continuously assigns different optimal spatial frequency responses to different cortical locations over the entire spatial frequency range.     

Numbness Following Total Knee Arthroplasty: Role of Incision Length And Position - A Randomized Study

BackgroundOne of the symptoms annoying patients after total knee replacement (TKR) is numbness around the operative scar. Some studies have shown that altering the incision in terms of placement or length may decrease the incidence of numbness. It still remains unknown whether numbness affects patient-reported outcomes.MethodsWe conducted a randomized study to compare a short-length incision (n = 50) and a lateral exit incision (n = 50) with a standard midline TKR incision (n = 50) in terms of the incidence of numbness and its progress over 1 year of follow-up. Our secondary objective was to look at the involved zone, area of numbness, and secondary symptoms. We also looked at patient-reported outcome in terms of satisfaction in all groups using a visual analog scale and Forgotten Joint Score.ResultsAt 3 months postoperatively, the incidence of numbness was least in the lateral exit group: 46.2% as compared to midline (62%) and short (58.3%), but the difference was not significant (p = 0.07). At 6 months, the short incision group had a significantly lower incidence (8%) of residual numbness as compared to 30% in the other two groups (p = 0.003). At 1 year, most patients recovered sensation loss and had similar function.ConclusionsPlacement or length of an incision did not significantly affect the incidence of numbness; however, the short incision led to early recovery of numbness. At 1 year of follow-up, most patients did not complain of loss of sensation and had similar functional outcome.     

Follicular bronchiolitis in primary ciliary dyskinesia

Ciliary dysfunction in primary ciliary dyskinesia (PCD) may be associated with bronchiolitis. Diffuse bronchiolitis has been reported in a subset of PCD patients who have Kartagener''s syndrome in Japan. We report a case of follicular bronchiolitis (FB) in a case of PCD presenting with recurrent episodes of cough, dyspnea, and bronchiectasis. This may motivate researchers to study rarer variants and presentations in PCD.     

A critical analysis of the concept of secondary Oral Hypoglycemic Agent (OHA) failure in type 2 diabetes at a tertiary care hospital

Data from UKPDS study suggests that the onset of ß cell dysfunction in diabetes occurs well before the development of hyperglycemia. To study the concept of secondary OHA failure in type 2 diabetes patients of more than 10 years duration in a tertiary care hospital. A retrospective analysis of all the cases of type 2 diabetes mellitus of more than 10 years duration from 2002 to 2003 was done and the data was divided into three groups: oral hypoglycemic agents (OHA) only, Insulin only, OHA + insulin. ANOVA/Students t test was the primary statistical test used. Odds ratio and 95% CI were calculated to compare risks of other diseases and drug use. 62.35% were on only OHAs, 8.82% on only insulin and 28.82% on both insulin and OHAs. This confirms good efficacy of OHAs. Diabetic population in our study tends to have a preserved beta cell function and secondary OHA failure is a late feature.     

Biochemical Urine Testing of Medication Adherence and Its Association With Clinical Markers in an Outpatient Population of Type 2 Diabetes Patients: Analysis in the DIAbetes and LifEstyle Cohort Twente (DIALECT)

OBJECTIVETo assess adherence to the three main drug classes in real-world patients with type 2 diabetes using biochemical urine testing, and to determine the association of nonadherence with baseline demographics, treatment targets, and complications.RESEARCH DESIGN AND METHODSAnalyses were performed of baseline data on 457 patients in the DIAbetes and LifEstyle Cohort Twente (DIALECT) study. Adherence to oral antidiabetics (OADs), antihypertensives, and statins was determined by analyzing baseline urine samples using liquid chromatography–tandem mass spectrometry. Primary outcomes were microvascular and macrovascular complications and treatment targets of LDL cholesterol, HbA_1c, and blood pressure. These were assessed cross-sectionally at baseline.RESULTSOverall, 89.3% of patients were identified as adherent. Adherence rates to OADs, antihypertensives, and statins were 95.7%, 92.0%, and 95.5%, respectively. The prevalence of microvascular (81.6% vs. 66.2%; P = 0.029) and macrovascular complications (55.1% vs. 37.0%; P = 0.014) was significantly higher in nonadherent patients. The percentage of patients who reached an LDL cholesterol target of ≤2.5 mmol/L was lower (67.4% vs. 81.1%; P = 0.029) in nonadherent patients. Binary logistic regression indicated that higher BMI, current smoking, elevated serum LDL cholesterol, high HbA_1c, presence of diabetic kidney disease, and presence of macrovascular disease were associated with nonadherence.CONCLUSIONSAlthough medication adherence of real-world type 2 diabetes patients managed in specialist care was relatively high, the prevalence of microvascular and macrovascular complications was significantly higher in nonadherent patients, and treatment targets were reached less frequently. This emphasizes the importance of objective detection and tailored interventions to improve adherence.