Age over 80 years is not associated with increased hemorrhagic transformation after stroke thrombolysis

Thrombolysis trials have recruited few patients aged ≥80 years, which has led to uncertainty about the likely risk-to-benefit profile in the elderly. Leukoaraiosis (LA) has been associated with hemorrhagic transformation (HT) and increases with advanced age. We tested whether there were any independent associations between age, LA and HT. Consecutive patients treated with intravenous (IV) tissue plasminogen activator (tPA) were identified from a prospective database. LA on baseline CT scans was assessed by two independent raters using the modified Van Swieten Score (mVSS) (maximum score 8, severe >4). HT was assessed on routine 24 hour to 48 hour CT /MRI scans using the European Cooperative Acute Stroke Study criteria for hemorrhagic infarct (HI) or parenchymal hematoma (PH) and judged symptomatic by the treating neurologist as per Safe Implementation of Thrombolysis in Stroke criteria. There were 206 patients treated with IV tPA (mean age: 71.0 years; range: 24-92 years), of whom 65/206 (32%) were aged ≥80 years. Overall, HT occurred in 41/206 patients (20%), HI in 31, PH1 in four (one symptomatic) and PH2 in six (three symptomatic). Age was not associated with HT (any HT: odds ratio [OR]=1.01; 95% confidence interval [CI]=0.5-2.08; p=0.99; PH: OR=0.53; 95% CI=0.12-2.3; p=0.51). There was one patient with PH1 and one patient with PH2 in 65 patients ≥80 years, both asymptomatic. LA was present in 112/208 (54%), and severe in 16.5%. LA increased with age (p<0.001) but was not associated with PH (any LA: OR=0.83; 95% CI=0.25-2.8; p=0.99; severe LA: OR=0.54, 95% CI=0.09-3.5; p=0.99). Age ≥80 years or LA did not increase the risk of HT (including PH) after thrombolysis, although LA increased with age. Neither factor should exclude otherwise eligible patients from tPA treatment.

Proliferating tricholemmal tumour: clinicopathological aspects of a case

We report the case of a 49-year-old man who presented with an enlarging mass over his occipital scalp. The clinical impression was either a squamous cell carcinoma or an unusual adnexal tumour. A wide excision was performed with skin grafting. Gross examination revealed a large exophytic tumour mass measuring 10 cm. Histopathological examination showed a circumscribed, well-differentiated squamoproliferative lesion with a lobulated architecture. Clear cell features, pilar-type keratinisation, microcalcifications and the presence of mucinous degeneration were noted. A diagnosis of proliferating tricholemmal tumour was made. This entity incorporates a spectrum of lesions, ranging from the mostly benign proliferating tricholemmal cyst to tumours having more atypical cellular and invasive features, the latter features correlating with an increased capacity for aggressive behaviour. Management-wise, such tumours require complete excision with follow-up. As the tumours are often large in size at presentation, reconstruction is required.

Discovery of small molecules that target autophagy for cancer treatment

Autophagy is a self-renewal process in cells by recycling redundant materials through lysosomal machinery. The basal level of autophagy in eukaryotic cells plays a "housekeeping" role by degrading redundant cellular materials and providing nutrients and energy. However acute and sustained autophagy may cause autophagic cell death. These two features of autophagy are consistent with its complex roles in both oncogenesis and cancer development. Many small molecule autophagy regulators are developed to turn autophagy on/off for therapeutic purpose. The roles of chemotherapeutic agents in regulating autophagy and facilitating cancer treatment can be classified into three categories: direct autophagy enhancers, indirect autophagy enhancers and autophagy inhibitors. The representative autophagy regulators and their roles in cancer treatment were reviewed.

Sequential expression of putative stem cell markers in gastric carcinogenesis

BACKGROUND

Gastric carcinogenesis has been well documented in the step-wise histopathological model, known as Correa pathway. Several biomarkers including CD44, Musashi-1 and CD133 have been reported as putative stem cell (PSC) markers.

METHODS

We investigated expression of PSC markers CD44, Musashi-1 and CD133 in relation to gastric carcinogenesis and prognosis and chemoresponse. Immunohistochemistry staining was performed in gastric cancer (GC) clinical specimens representing different steps of the Correa pathway. Gastric cancer samples taken before and after neoadjuvant chemotherapy with docetaxel, cisplatin and capecitabine (DCX) were also evaluated for PSC marker expression.

RESULTS

We showed that the expression of three PSC markers was significantly elevated in GC relative to normal gastric mucosa (P<0.001 for each marker). Precancerous lesions, including intestinal metaplasia and dysplasia, demonstrated increased expression of CD44 and Musashi-1. CD133 was predominantly expressed along the border between intramucosal carcinoma and connective tissue at later stages. High CD44 and CD133 expression showed prognostic value for worse patient survival (P=0.014 and P=0.019, respectively). A small number of tumours with high expression of CD44 and CD133 showed pathological response to DCX-based neoadjuvant chemotherapy.

CONCLUSION

CD44 and Musashi-1 are frequently expressed in both premalignant gastric lesions and invasive GC, whereas CD133 expression is restricted mainly to neoplastic tissues.

Determination of Ameliorable Health Impairment Influencing Health-Related Quality of Life among Patients with Silicosis in China: A Cross-Sectional Study

The association between health-related quality of life (HRQOL) and ameliorable health impairment was examined in 208 Chinese in-patients with silicosis, in April 2010. Median St George's Respiratory Questionnaire scores for symptom and activity impairment, social support rating scale and geriatric depression scale scores for patients were 57.24, 59.45, 35 and 5, respectively. Median 36-item short-form health survey physical component (PCS) and mental component (MCS) scores were 47.17 and 51.05, respectively. Lower than median PCS scores (< 47) were significantly associated with high levels of symptom and activity impairment. Lower than median MCS scores (< 51) were significantly associated with high levels of depression and activity impairment. Encouraging patients to participate in daily activities may alleviate activity impairment. Reasonable financial compensation may help to maintain and improve social support levels.

IDH1 and IDH2 mutations in pediatric acute leukemia

To investigate the frequency of isocitrate dehydrogenase 1 (IDH1) and 2 (IDH2) mutations in pediatric acute myeloid leukemia (AML) and acute lymphoid leukemia (ALL), we sequenced these genes in diagnostic samples from 515 patients (227 AMLs and 288 ALLs). Somatic IDH1/IDH2 mutations were rare in ALL (N=1), but were more common in AML, occurring in 3.5% (IDH1 N=3 and IDH2 N=5), with the frequency higher in AMLs with a normal karyotype (9.8%). The identified IDH1 mutations occurred in codon 132 resulting in replacement of arginine with either cysteine (N=3) or histidine (N=1). By contrast, mutations in IDH2 did not affect the homologous residue but instead altered codon 140, resulting in replacement of arginine with either glutamine (N=4) or tryptophan (N=1). Structural modeling of IDH2 suggested that codon 140 mutations disrupt the enzyme's ability to bind its substrate isocitrate. Accordingly, recombinant IDH2 R140Q/W were unable to carry out the decarboxylation of isocitrate to α-ketoglutarate (α-KG), but instead gained the neomorphic activity to reduce α-KG to R(-)-2-hydroxyglutarete (2-HG). Analysis of primary leukemic blasts confirmed high levels of 2-HG in AMLs with IDH1/IDH2 mutations. Interestingly, 3/5 AMLs with IDH2 mutations had FLT3-activating mutations, raising the possibility that these mutations cooperate in leukemogenesis.

H63D polymorphism in the hemochromatosis gene is associated with sporadic amyotrophic lateral sclerosis in China

BACKGROUND AND PURPOSE

The H63D polymorphism in the hemochromatosis (HFE) gene has been reported as a risk factor for amyotrophic lateral sclerosis (ALS) in Europe and America, but no data have been reported for Asia. Here, we investigated the possible association between H63D and sporadic ALS (sALS) in a Chinese Han population.

METHODS

A total of 195 individuals with sALS from three centers in China and 405 unrelated healthy controls were recruited. All subjects were genotyped by restriction fragment length polymorphism (RFLP) analysis.

RESULTS

Sporadic ALS was significantly related to the H63D polymorphism in heterozygous carriers (odds ratio 3.10, 95%CI: 1.49-6.47, P=0.002).

CONCLUSIONS

The HFE H63D polymorphism may contribute to the development of sALS in Chinese.

Metformin vs thiazolidinediones for treatment of clinical, hormonal and metabolic characteristics of polycystic ovary syndrome: a meta-analysis

OBJECTIVES

Insulin-sensitizing drugs (ISDs) have been advocated for the long-term treatment of polycystic ovary syndrome (PCOS). It is therefore important to compare the efficacy and safety of ISDs such as metformin and thiazolidinediones (TZDs) for the treatment of this syndrome.

METHODS

A meta-analysis to assess the effectiveness and safety of metformin vs TZDs (including pioglitazone and rosiglitazone) in the treatment of PCOS was conducted, using MEDLINE (1966-May 2010) and EMBASE (1988-May 2010) to select randomized controlled trials comparing clinical, hormonal and metabolic results.

RESULTS

Ten trials were included. TZDs were superior to metformin in reducing serum levels of free testosterone (P=0.03) and dehydroepiandrosterone sulfate (DHEA) (P=0.002) after 3 months treatment. Decreases in triglyceride levels were more pronounced with metformin after 6 months (P<0.0001). Decreases in body mass index (BMI) were greater with metformin treatment as assessed at 3 and 6 months (P<0.00001). There were no significant between-group differences concerning improvements in ovulation, pregnancy rate, menstrual patterns or insulin sensitivity, or changes in serum levels of androstenedione, luteinizing hormone, follicle-stimulating hormone, total cholesterol, low-density lipoprotein C or insulin. Metformin caused a significantly higher incidence of side effects such as nausea, diarrhoea and abdominal cramping (P<0.00001). Significant between-study heterogeneity was detected for several variables assessed.

CONCLUSIONS

The findings from this meta-analysis do not indicate that metformin is superior to TZD's for the treatment of PCOS or vice versa. Between studies, heterogeneity was a major confounder. A large scale, well-designed, randomized, controlled trial is needed to further address this issue.

Structural Defects in GaN Epilayers Grown by Gas Source Molecular Beam Epitaxy

Single crystal cubic or hexagonal GaN thin films have been grown on various substrates, using a modified gas source MBE technique. A standard effusion cell was employed for the evaporation of gallium. A compact electron cyclotron resonance plasma source was used to activate the nitrogen prior to deposition. The films were examined by transmission electron microscopy. The major defects in the wurtzite GaN were double positioning boundaries, inversion domain boundaries, and dislocations. The zinc-blende GaN showed microtwins, stacking faults, and dislocations. The connection between the observed structural defects and the poor electrical properties of GaN is noted.

Glasgow coma scale does not predict outcome post-intra-arterial treatment for basilar artery thrombosis

BACKGROUND AND PURPOSE

Evidence to guide patient selection for IA therapy in acute basilar artery thrombosis is lacking. The GCS is frequently used as a selection criterion, based on the view that higher GCS correlates with better neurologic outcome. This view has not been systematically studied. We hypothesize that low GCS does not correlate with poor outcome and that it should not preclude IA therapy.

MATERIALS AND METHODS

We included 40 consecutive patients with basilar artery thrombosis treated with IA therapy. Clinical characteristics, GCS, time to intervention, and postprocedural TIMI scores were collected. Recanalization was defined as TIMI grade 2 or 3; clinical outcome was measured by 90-day mRS.

RESULTS

Median patient age was 63.5 years. Most presented with gaze palsies (67.5%) or hemiparesis (45%). Median GCS was 9, the median time to intervention was 7.2 hours, and recanalization rate was 82.5%. Good neurologic outcome (mRS ≤ 1) occurred in 30%. There was no correlation between GCS and 90-day mRS (Spearman ρ - 0.174, P = .283). Equal numbers of patients with good neurologic outcome of mRS ≤ 1 (n = 12) had a GCS of ≤6 or >6. In those with GCS ≤ 6 for >3 hours, 33.3% had good neurologic outcome-a similar rate to that of the overall cohort. Statistical significance was demonstrated between time to IA therapy within 6 hours and mRS ≤ 2.

CONCLUSIONS

Low GCS score did not correlate with poor neurologic outcome in patients with acute basilar artery thrombosis managed with IA therapy. It is not appropriate to exclude patients from IA therapy on the basis of low GCS.

Analysis of Plasma Properties and Deposition of Amorphous Silicon Alloy Solar Cells Using Very High Frequency Glow Discharge

Positive ionic energy distributions in modified very-high-frequency (MVHF) and radio frequency (RF) glow discharges were measured using a retarding field analyzer. The ionic energy distribution for H2 plasma with 75 MHz excitation at a pressure of 0.1 torr has a peak at 22 eV with a half-width of about 6 eV. However, with 13.56 MHz excitation, the peak appears at 37 eV with a much broader half-width of 18 eV. The introduction of SiH4 to the plasma shifts the distribution to lower energy. Increasing the pressure not only shifts the distribution to lower energy but also broadens the distribution. In addition, the ionic current intensity to the substrate is about five times higher for MVHF plasma than for RF plasma. In order to study the effect of ion bombardment, the deposition of a-Si alloy solar cells using MVHF was investigated in detail at different pressures and external biases. Lowering the pressure and negatively biasing the substrate increases ion bombardment energy and results in a deterioration of cell performance. It indicates that ion bombardment is not beneficial for making solar cells using MVHF. By optimizing the deposition conditions, a 10.8% initial efficiency of a-Si/a-SiGe/SiGe triple-junction solar cell was achieved at a deposition rate of 0.6 nm/sec.

Light Soaking and Thermal Annealing Effects on the Micro-Electrical Properties of Amorphous and Nanocrystalline Mixed-phase Silicon Solar Cells

We report on the measurement of local current flow in hydrogenated amorphous and nanocrystalline mixed-phase n-i-p silicon solar cells in the initial, light-soaked, and annealed states using conductive atomic force microscopy (C-AFM). The C-AFM measurement shows that the nanometer-size grains aggregate, and the local current densities in the nanocrystalline aggregation areas decreased significantly after light soaking and recovered to values similar to the initial state after annealing at a high temperature in a vacuum. This result supports the model of two parallel-connected diodes for explaining the light-induced open-circuit voltage increase in the mixed-phase solar cells.

Light-Soaking Effects on the Open-Circuit Voltage of a-Si:H Solar Cells

We present measurements on the decline of the open-circuit voltage VOC in a-Si:H solar cells during extended illumination (light-soaking) at 295 K. We used a near-infrared laser that was nearly uniformly absorbed in the intrinsic layer of the cell. At the highest photogeneration rate (about 2x1021 cm-3), a noticeable decline (0.01 V) occurred within about 10 minutes; VOC stabilized at 0.04 V below its initial value after about 200 hours. We found that both the kinetics and the magnitudes of VOC are reasonably consistent with the predictions of a calculation combining a bandtail+defect picture for recombination and a hydrogen-collision model for defect generation. The version of the hydrogen-collision model that we used assumes that only bandtail recombination drives the hydrogen collision processes. Within this picture, the crossover between bandtail and defect recombination occurs on the same timescale as the “light-induced annealing” process that accounts for stabilization of the optoelectronic properties for long lightsoaking times.