Proliferation, differentiation and amyloid-β production in neural progenitor cells isolated from TgCRND8 mice

The amyloid precursor protein (APP) and amyloid-β (Aβ) peptide play central roles in the pathology and etiology of Alzheimer's disease. Amyloid-induced impairments in neurogenesis have been investigated in several transgenic mouse models but the mechanism of action remains to be conclusively demonstrated. The changes in neurogenesis during this transition of increasing Aβ levels and plaque formation were investigated in the present study. We found that the proliferation of newborn cell in the dentate gyrus was enhanced prior to elevations in soluble Aβ production as well as amyloid deposition in 5-week-old TgCRND8 mice, which are well-established Alzheimer's disease models, compared to non-transgenic (Non-Tg) mice. The number of BrdU-positive cells remained higher in TgCRND8 vs Non-Tg mice for a period of 8weeks. The numbers of BrdU/NeuN-positive cells were not significantly different in TgCRND8 compared to Non-Tg mice. A significant decrease in BrdU/GFAP but not in BrdU/S100β was found in Tg vs Non-Tg at 6-weeks of age. In addition, a unique observation was made using isolated neuroprogenitor cells from TgCRND8 mice which were found to be less viable in culture and produced substantial amounts of secreted Aβ peptides. This suggests that the proliferation of neural progenitors in vivo may be modulated by high levels of APP expression and the resulting Aβ generated directly by the progenitor cells. These findings indicate that cell proliferation is increased prior to Aβ deposition and that cell viability is decreased in TgCRND8 mice over time.

A Pictorial Review of Diabetic foot Manifestations

The diabetic foot with its many associated complications and presentations can provide a challenge in diagnosis and subsequent treatment. MRI, being increasingly available commonly, is now the main investigative modality. In particular, it is helpful in differentiating between neuroarthropathy and osteomyelitis and in cases where the latter is superimposed on the former. By being well versed in the interpretation of the images, the radiologist can make crucial contribution to the care and management of these patients.

Cardiogenic shock as the initial presentation of neonatal systemic hypertension

Neonatal systemic hypertension is an underappreciated etiology of cardiac failure. We present a series of three neonates who presented in cardiogenic shock secondary to severe hypertension, recognized after initial resuscitation efforts. Although the underlying etiology of the hypertension varied, all three patients had improved hemodynamics after their blood pressure was controlled. These cases suggest that neonates presenting in cardiogenic shock with hypertension, and without structural heart disease, may benefit from a thorough renal evaluation and institution of anti-hypertensive therapy.

Decorin biology, expression, function and therapy in the cornea

Decorin is a small leucine-rich proteoglycan (SLRP) that plays a vital role in many important cellular processes in several tissues including the cornea. A normal constituent of the corneal stroma, decorin is also found in the majority of connective tissues and is related structurally to other small proteoglycans. It interacts with various growth factors such as epidermal growth factor (EGF) and transforming growth factor beta (TGFβ) to regulate processes like collagen fibrillogenesis, extracellular matrix (ECM) compilation, and cell-cycle progression. Studies have linked decorin dysregulation to delayed tissue healing in patients with various diseases including cancer. In the cornea, decorin is involved in the regulation of transparency, a key function for normal vision. It has been reported that mutations in the decorin gene are associated with congenital stromal dystrophy, a disease that leads to corneal opacity and visual abnormalities. Decorin also antagonizes TGFβ in the cornea, a central regulatory cytokine in corneal wound healing. Following corneal injury, increased TGFβ levels induce keratocyte transdifferentiation to myofibroblasts and, subsequently, fibrosis (scarring) in the cornea. We recently reported that decorin overexpression in corneal fibroblasts blocks TGFβ-driven myofibroblast transformation and fibrosis development in the cornea in vitro suggesting that decorin gene therapy can be used for the treatment of corneal scarring in vivo.

Risk factors for aortic valve disease in bicuspid aortic valve: a family-based study

Bicuspid aortic valve (BAV) is the most common cardiovascular malformation and is a risk factor for aortic valve disease (AVD). AVD typically manifests later in life, and the majority of cases have BAV. The purpose of this study was to identify risk factors for AVD in individuals with BAV. Families enriched for BAV were identified in a pediatric population, and echocardiography was performed on all family members. AVD was identified as stenosis and/or insufficiency, and BAV morphology was defined as right-left (RL), right-non (RN) or indeterminate. Heritability (h(2)) of AVD and BAV morphology was estimated using variance components analysis (SOLAR). To assess AVD risk over time, we used Generalized Estimating Equations methodology (SAS) adjusting for age and gender. A total of 1,128 individuals from 226 families were evaluated. BAV was identified in 281 individuals (25%), and AVD was identified in 167 (59%) individuals with BAV. Previously, we identified a high heritability for BAV (h(2)  = 0.89 ± 0.06, P < 0.00001), but the heritability of AVD in the present study (0.07 ± 0.17, P = 0.33) was low. AVD was significantly associated with BAV morphology (P = 0.0027) and age (P = 0.0068). Children with RN BAV and adults with RL BAV were more likely to develop AVD. BAV is determined largely by genetic effects, but the phenotypic variability of AVD is primarily determined by nongenetic factors. BAV morphology may have predictive value for the time course of AVD.

A case report of chronic frontal bone osteitis presenting with recurrent unilateral lid swelling

Despite the advances in modern antimicrobial treatment, paranasal sinus disease remains relatively common. A case of chronic inflammatory frontal sinus disease presented with unilateral recurrent eyelid swelling. Clinical features and management in conjunction with ENT are discussed. An extensive literature search has shown only one other similar case reported in Russian language whose management details however are not available.

Necrotising fasciitis of the cervicofacial region: a bizarre presentation

The following paper presents the case of a middle-aged woman, who presented with a necrotising soft tissue infection of the cervicofacial region with maggots in situ. She was managed with aggressive surgical debridement, but eventually succumbed to the disease because of erosion of the great vessels of the neck by the maggots. The purpose of this case report is to emphasise the severity of this disease and also to present an unusual case, which had a fatal outcome.

Mature ovarian dermoid cyst invading the urinary bladder

Mature ovarian dermoid cysts are common lesions, accounting for up to 10-25% of all ovarian neoplasms. Uncomplicated dermoid cysts are often asymptomatic and are relatively easy to diagnose on imaging and to treat. Symptoms develop once complications set in and these may cause diagnostic dilemmas. Torsion (16%) is the most common complication, while rupture, suppuration and malignant transformation are relatively uncommon. Of all these complications, spontaneous rupture into the urinary bladder is least common. The diagnosis of this condition has been through the use of cystoscopy or laparotomy in all cases reported so far. We report a case of a 30-year-old patient with pyuria and dysuria, where ultrasound examination clearly demonstrated an ovarian dermoid cyst invading the urinary bladder. A clear-cut imaging diagnosis helped to allow planning of surgery in advance and a mucosa-sparing partial bladder resection could be performed.

Temporal summation of heat pain in humans: Evidence supporting thalamocortical modulation

Noxious cutaneous contact heat stimuli (48 degrees C) are perceived as increasingly painful when the stimulus duration is extended from 5 to 10s, reflecting the temporal summation of central neuronal activity mediating heat pain. However, the sensation of increasing heat pain disappears, reaching a plateau as stimulus duration increases from 10 to 20s. We used functional magnetic resonance imaging (fMRI) in 10 healthy subjects to determine if active central mechanisms could contribute to this psychophysical plateau. During heat pain durations ranging from 5 to 20s, activation intensities in the bilateral orbitofrontal cortices and the activation volume in the left primary (S1) somatosensory cortex correlated only with perceived stimulus intensity and not with stimulus duration. Activation volumes increased with both stimulus duration and perceived intensity in the left lateral thalamus, posterior insula, inferior parietal cortex, and hippocampus. In contrast, during the psychophysical plateau, both the intensity and volume of thalamic and cortical activations in the right medial thalamus, right posterior insula, and left secondary (S2) somatosensory cortex continued to increase with stimulus duration but not with perceived stimulus intensity. Activation volumes in the left medial and right lateral thalamus, and the bilateral mid-anterior cingulate, left orbitofrontal, and right S2 cortices also increased only with stimulus duration. The increased activity of specific thalamic and cortical structures as stimulus duration, but not perceived intensity, increases is consistent with the recruitment of a thalamocortical mechanism that participates in the modulation of pain-related cortical responses and the temporal summation of heat pain.

Clinical and immunohistochemical prognostic factors in adult glioblastoma patients

OBJECTIVE

Glioblastomas are the commonest and the most malignant of all adult brain tumors, characterized by genetic instability, intratumoral histopathological variability, and unpredictable clinical behavior. The utility of tumor markers that reflect their underlying biology is becoming increasingly important with respect to patient prognostication and their potential role as molecular targets of therapy is being recognized. In this study, we aimed to identify the clinical factors and some immunohistochemical markers that could have an effect on patient survival in supratentorial glioblastomas.

MATERIALS AND METHODS

We evaluated 54 cases of adult supratentorial glioblastomas operated over a span of 1 year, with respect to clinical features such as age, Karnofsky performance score (KPS), extent of resection, adjuvant therapy, and immunohistochemical expression of p53, EGFR (Epidermal Growth Factor Receptor) and PTEN (Phosphatase and Tensin homolog).

RESULTS

Radiotherapy and KPS at presentation were significant predictors of outcome in both univariate and multivariate analyses. Among immunohistochemical variables; loss of PTEN expression in association with over-expression of EGFR showed a trend towards poorer survival, in univariate analysis. Over-expression of EGFR and/or p53 emerged as significant predictors of poor outcome on multivariate analysis, despite failing to prognosticate on univariate analysis.

CONCLUSIONS

Our study shows that EGFR and p53 overexpression along with loss of PTEN expression are important adjuncts to clinical variables in prognosticating glioblastoma patients.

Admixture mapping of ankle-arm index: identification of a candidate locus associated with peripheral arterial disease

BACKGROUND

Peripheral arterial disease (PAD) is associated with significant morbidity and mortality, and has a higher prevalence in African Americans than Caucasians. Ankle-arm index (AAI) is the ratio of systolic blood pressure in the leg to that in the arm, and, when low, is a marker of PAD.

METHODS

The authors used an admixture mapping approach to search for genetic loci associated with low AAI. Using data from 1040 African American participants in the observational, population based Health, Aging, and Body Composition Study who were genotyped at 1322 single nucleotide polymorphisms (SNPs) that are informative for African versus European ancestry and span the entire genome, we estimated genetic ancestry in each chromosomal region and then tested the association between AAI and genetic ancestry at each locus.

RESULTS

The authors found a region of chromosome 11 that reaches its peak between 80 and 82 Mb associated with low AAI (p<0.001 for rs12289502 and rs9665943, both within this region). 753 African American participants in the observational, population based Cardiovascular Health Study were genotyped at rs9665943 to test the reproducibility of this association, and this association was also statistically significant (odds ratio (OR) for homozygous African genotype 1.59, 95% confidence interval (CI) 1.12 to 2.27). Another candidate SNP (rs1042602) in the same genomic region was tested in both populations, and was also found to be significantly associated with low AAI in both populations (OR for homozygous African genotype 1.89, 95% CI 1.29 to 2.76).

CONCLUSION

This study identifies a novel region of chromosome 11 representing an area with a potential candidate gene associated with PAD in African Americans.

Spontaneous transmural migration of retained surgical textile into both small and large bowel: a rare cause of intestinal obstruction

Retained surgical textile is an infrequent but serious complication of abdominal surgery. Diagnosis is often delayed owing to non-specific clinical symptoms and inconclusive imaging features. Medicolegal implications further complicate the issue. We report a case of a 30-year-old woman who had previously undergone caesarean section and who presented with pain and features of intestinal obstruction. Contrast-enhanced CT revealed a heterogeneous ill-defined mass with mottled air densities lying within both the large and the small bowel. Barium study beautifully demonstrated the intraluminal mass in the transverse colon extending into the jejunum, with a fistulous communication between the two loops. To the best of our knowledge, this is the first reported case in which the gauze migrated simultaneously into the large and small bowel, and where the exact site of migration was clearly mapped out on pre-operative imaging studies.