High-definition imaging of trabeculectomy blebs using spectral domain optical coherence tomography adapted for the anterior segment

Background:  The aim of this work was to image trabeculectomy blebs using spectral domain optical coherence tomography (SDOCT).
Methods:  In this prospective cross-sectional study, patients who had undergone trabeculectomy with at least 3 months of follow up were included. Blebs were imaged using an adapted SDOCT system (Cirrus HD-OCT, Carl Zeiss Meditec Inc., Dublin, CA, USA) and time domain anterior segment optical coherence tomography (ASOCT) (Visante OCT, Carl Zeiss Meditec Inc.). An observer masked to clinical data assessed the utility of SDOCT and ASOCT in visualizing structures in successful and failed blebs.
Results:  Fifty-one eyes were imaged, of which 43 (84.3%) were successful. SDOCT showed wall thickening (93.0% vs. 67.4%, P  = 0.006) and discrete hyporeflective spaces in the wall (88.4% vs. 14.0%, P  < 0.0001) in a greater proportion of successful blebs than ASOCT. SDOCT showed the bleb cavity (23.3% vs. 48.8%, P  = 0.02), scleral flap (34.9% vs. 90.7%, P  < 0.0001), subflap space (20.9% vs . 72.1%, P  < 0.0001) and ostium (9.3% vs. 88.4%, P  < 0.0001) in fewer successful blebs than ASOCT. The internal ostium was not visualized in any failed bleb using SDOCT, whereas ASOCT showed the ostium in 87.5% of failed blebs ( P  = 0.001). SDOCT showed cystic spaces in the bleb wall in a greater proportion of successful blebs than failed blebs (88.4% vs. 37.5%, P  = 0.005).
Conclusions:  SDOCT imaging was able to show fine superficial features in the bleb wall. However, SDOCT had limited clinical utility in that it did not provide useful information about deep features such as flap position, bleb cavity formation or patency of the subflap space and internal ostium.     

The clinical and pathological characteristics of Chinese patients with pauci-immune crescent golmerulonephritis

Objective　To investigate the clinical and pathological characteristics of pauci-immune crescent glomerulo～nephritis (PICGN) in Chinese patients. Methods　During 13 years (1985-1998), 6400 patients underwent non-transplanting renal biopsy. Twenty-four patients were diagnosed as PICGN. All clinical and laboratory data of these patients were collected from the patients’ records and used for detailed analysis. The diagnosis is based on clinico-pathologic findings. Results　Of the 24 patients, 16 were females and 8 were males, with median age of 33 years (ranged 10-76 years). Microscopic polyarteritis (MPA) (33.3%) and systemic vasculitis (8.3%) were the secondary diseases. The incidence of PICGN was 0.38% in renal biopsies and 22.9% in crescentic glomerulonephritis. Clinically, most patients (75.0%) showed rapidly progressive nephritis with enlarged kidneys. At onset, gross hematuria was noted in 58.3% of patients, hypertension in 45.8%, nephrotic syndrome in 41.7%, and oliguria in 25.0%. However, systemic symptoms were rare except for anemia. Pathologically, necrosis of glomerular capillaries (62.5%), infiltration of monocytes and neutrophil cells in glomeruli (66.7%), and vasculitis in the interstitium (53.3%) were observed. In addition, glomerulosclerosis was noted in 45.8%, severe tubular atrophy in 83.3% and interstitial fibrosis in 75.0%. Anti-neutrophil cytoplasmic antibodies (ANCAs) were positive in 52.2%. All patients except two received intensively immunosuppressive therapy. Sixteen patients were available for long-term follow up (median 29.8 months, range 8-92 months). Twelve of them had life-sustaining renal function, four had normal serum creatinine (&lt;124?μmol/L) and only 4 patients were dialysis-dependent. Conclusion　PICGN is not rare in China. Early diagnosis and administration of immunosuppressive therapy, particularly in patients with rapidly progressive glomerulonephritis (RPGN), are important for good prognosis.     

Volumetric evaluation of the sphenoid sinus among different races in the Southeast Asian (SEA) population: a computerized tomography study

Introduction: The fundament of forensic science lies in identifying a body. The morphological complexity of the paranasal sinus (PNS), which varies greatly amongst individual, possess a discriminatory value that potentially contributes to the radiological identification. The sphenoid bone represents the keystone of the skull and forms part of the cranial vault. It is intimately associated with vital neurovascular structures. The sphenoid sinus, located within the body of the sphenoid bone, has variable morphology. The sphenoid septum''s inconsistent position and the degree, as well as the direction disparities of sinus pneumatization, have indeed accorded it a unique structure in providing invaluable information in forensic personnel identification. Additionally, the sphenoid sinus is situated deep within the sphenoid bone. Therefore, it is well protected from traumatic degradation from external causes and can be potentially utilized in forensic studies. The authors aim to study the possibility of variation among the race, and gender in the Southeast Asian (SEA) population, using volumetric measurements of the sphenoid sinus.Materials and methods: This is a retrospective cross-sectional analysis of computerized tomographic (CT) imaging of the PNS of 304 patients (167 males, 137 females) in a single centre. The volume of the sphenoid sinus was reconstructed and measured using commercial real-time segmentation software.Result: The total volume of sphenoid sinus of male gender had shown to be larger, 12.22 (4.93 - 21.09) cm³ compared to the counterpart of 10.19 (3.75 - 18.72) cm³ (p = .0090). The Chinese possessed a larger total sphenoid sinus volume, 12.96 (4.62 - 22.21) cm³) than the Malays, 10.68 (4.13 - 19.25) cm³ (p = .0057). No correlation was identified between the age and volume of the sinus (cc= -.026, p = .6559).Conclusion: The sphenoid sinus volume in males was found to be larger than those of females. It was also shown that race influences sinus volume. Volumetric analysis of the sphenoid sinus can potentially be utilized in gender and race determination. The current study provided normative data on the sphenoid sinus volume in the SEA region, which can be helpful for future studies.     

Granulocyte-macrophage colony-stimulating factor: signals for its mRNA accumulation

Granulocyte-monocyte colony-stimulating factor (GM-CSF) is an important hematopoietic growth factor. Mesenchymal cells produce abundant GM-CSF in response to tumor necrosis factor alpha (TNF). We wished to determine (1) what cellular pathways enhanced levels of GM-CSF mRNA, and (2) if TNF used any of these pathways. Modulation in levels of GM- CSF mRNA in human fibroblasts (WI-38) was studied by using Northern blot analysis. Markedly increased levels of GM-CSF mRNA occurred in these cells after exposure to sodium fluoride (NaF) and the effect of NaF was slightly enhanced by aluminum chloride; these results suggest that accumulation of GM-CSF mRNA can occur by activating a G-binding protein. Stimulators of protein kinase C dramatically increased levels of GM-CSF mRNA; however, blockade of protein kinase C activity did not attenuate accumulation of GM-CSF mRNA stimulated by TNF and NaF. Exposure to ouabain increased levels of GM-CSF mRNA and this effect was prominently enhanced in the presence of low concentrations of extracellular K+ and was almost abolished in high concentrations of extracellular K+. A monovalent ionophore (monensin) also increased levels of GM-CSF mRNA. Both ouabain and monensin can increase intracellular Ca++ concentration (Cai++) through Na+-Ca++ exchange. A calcium channel blocker (diltiazem) blocked the increased levels of GM- CSF mRNA mediated by ouabain, but could not block the stimulation mediated by TNF alpha. Ca++ ionophores also increased levels of GM-CSF mRNA and rapidly increased levels of Cai++. TNF did not increase Cai++ and, moreover, was able to stimulate accumulation of GM-CSF mRNA in the absence of extracellular Ca++. Taken together, we have found that several different cellular pathways can lead to prominent accumulation of GM-CSF mRNA in mesenchymal cells including (1) activation of protein kinase C, (2) increase in Cai++, and (3) stimulation of G-binding protein. Our studies show that TNF appears to increase levels of GM-CSF mRNA independent of protein kinase C activity or levels of Cai++.     

Earprints in forensic investigations

This article provides an overview of the theoretical and practical issues surrounding the use of earprints in forensic research. In the first section, we provide a limited account of the history of earprints in forensic investigations and their use as evidence in court. Criticism of the use of earprints for individualization is addressed and fundamental questions that require attention are summarized. In the second section, we summarize the results of various studies that we have performed on earprint variation. Potential causes of intraindividual variation in earprint appearance are, for instance, variations in the way the prints are lifted, variations in the time the donor spends listening, and variations in the force that is applied during listening. Concerning the latter, we have explored various factors that could influence applied force. We have also studied changes in the morphology of live ears during adulthood.     

Relapse cell population differs from acute onset clone as shown by absence of the initially activated N-ras oncogene in a patient with acute myelomonocytic leukemia

We have conducted a follow-up study of a patient with myelomonocytic leukemia exhibiting an N-ras mutation (Gln61----Lys61) using the polymerase chain reaction method and synthetic oligonucleotide hybridization probes. This method allowed us to detect as little as 3% of N-ras-mutated cells within a population. When the patient went into clinical remission, the mutation became undetectable. When a relapse occurred, the blasts did not carry the N-ras mutation. Analysis of M13 cloned amplified N-ras sequences from relapse DNA revealed exclusively the wild type allele of the N-ras gene. These findings suggest that the relapse cell population is derived from a different clone than the acute phase population. Furthermore, the data argue that N-ras mutation is not an initiating lesion in this case of acute myelomonocytic leukemia (AMML).     

Quantification of blood flow with dynamic MR imaging and presaturation bolus tracking

A technique is described for rapid imaging of blood flow and dynamic measurement of its velocity. The method is a combination of bolus tracking and low-flip-angle gradient-echo cine angiography. This method provides precise determination of velocity with high temporal resolution in a single measurement. Unlike what occurs in phase imaging techniques, flow is displayed directly, eliminating potential errors that result from non-flow-related sources of phase shifts. Manipulation of raw data sets is avoided. Results obtained from a flow phantom, healthy volunteers, and a patient with an aortic aneurysm demonstrate the capability of the technique to track flow at low and high velocities and to differentiate flowing blood from thrombus. Because of its conceptual simplicity, rapidity, and lack of susceptibility to extraneous phase shifts, this technique may prove ideal for in vivo flow measurement and evaluation of flow patterns.