Dissociation of explicit and implicit long-term memory consolidation in semantic dementia: a case study

We report a case study of a semantic dementia patient, whose episodic memory consolidation was tested over a 2-month period. The results reveal that despite early retention of information, the patient lost all explicit information of the newly learnt material after 2 weeks. By contrast, he retained implicit word information even after a 4-week delay. These findings highlight the critical time window of 2-4 weeks in which newly learnt information should be re-encoded in rehabilitations studies. The results also indicate that learnt information can be still accessed with implicit retrieval strategies when explicit retrieval fails.

Dose-related effect by maternal exposure to di-(2-ethylhexyl) phthalate plasticizer on inducing hypospadiac male rats

The aim of this study was to evaluate dose-related effects on external genitalia of adult male offspring rats by maternal exposure to di-(2-ethylhexyl) phthalate (DEHP) plasticizer. Timed-pregnant rats were given DEHP by gastric intubation at doses of 0, 500, 750 or 1000mg/kg body weight/day from gestation day 12-19 to establish a hypospadiac rat model. The hypospadias was observed and the incidence in three DEHP dosage levels was 10.7%, 30.6% and 37.0%, respectively. With exposed dose increased, mild, moderate and severe hypospadiac rats were distinguished and an increased incidence of severe hypospadias was observed. The other reproductive lesions like reduced penile length and anogenital distance/body weight were observed. The results indicated the dose-related external genitalia teratogenic toxicity, and graded hypospadias on male offspring was resulted from high dosage DEHP maternal exposure.

blaKPC and rmtB on a single plasmid in Enterobacter amnigenus and Klebsiella pneumoniae isolates from the same patient

Enterobacter amnigenus (EA76) and Klebsiella pneumoniae (KP76) isolates with multidrug-resistant (MDR) patterns were identified from the same patient in the neurosurgery department of our hospital. An outbreak of MDR K. pneumoniae had also occurred in this department. To characterize the resistance mechanism and molecular epidemiology of these isolates, sequential experiments including antimicrobial susceptibility testing, polymerase chain reaction (PCR), plasmid analysis, pulsed field gel electrophoresis (PFGE), and multilocus sequence typing (MLST) were performed. EA76 and KP76 were resistant to all of the antibiotics tested, except colistin and tigecycline. bla_KPC-2, bla_TEM-1, bla_SHV-12, bla_CTX-M-3, bla_CTX-M-14, and rmtB genes were identified in both isolates, with bla_KPC-2, bla_TEM-1, bla_CTX-M-14, and rmtB being co-carried on one plasmid in each isolate. Further analysis showed different restriction patterns between the two KPC-carrying plasmids. Of the 11 carbapenem-resistant isolates found in the outbreak, all were resistant to all of the β-lactams tested, with 63.64% (7/11) also exhibiting resistance to aminoglycosides and 72.73% (8/11) exhibiting resistance to quinolones. PCR analysis and molecular typing of the 11 K. pneumoniae strains revealed that the seven aminoglycoside-resistant isolates shared the same antibiotic-resistant gene pattern and identical or one-band-difference PFGE profiles relative to KP76. In addition, all of the eight aminoglycoside-resistant isolates, including KP76, belonged to the national epidemic clone ST11. The overall results indicate the emergence of E. amnigenus and outbreak of ST11 K. pneumoniae, with both co-harboring bla_KPC and rmtB genes on a single plasmid in our neurosurgery wards.

Effectiveness of applying arsenate reducing bacteria to enhance arsenic removal from polluted soils by Pteris vittata L

Arsenic is a common contaminant in soils and water. It is well established that the fern Pteris vittata L. is an As hyperaccumulator and therefore has potential to phyroremediate As-polluted soils. Also, it is accepted that rhizosphere microflora play an enhancing role in plant uptake of metallic elements from soils. Studies showed that hydroponiclly grown P. Vittata accumulated arsenite more than the arsenate form of As apparently because arsenate and phosphate are analogues and therefore its absorption is inhibited by phosphate. The objective of this study was to determine whether addition of five different arsenate-reducing bacteria would enhance arsenic uptake by P. vittata grown in arsenic polluted soils in afield experiment. Results showed that addition of the As reducing bacteria promoted the growth of P. vittata, increased As accumulation, activated soil insoluble As, and reduced As leaching compared to the untreated control. Plant biomass increased by 53% and As uptake by 44%. As leaching was reduced by 29% to 71% depending on the As reducing bacterium. The results in their entirety permitted some insight into the mechanisms by which the arsenate reducing bacteria enhanced the effectiveness of P. vittata to remove As from the polluted soil.

The metabolic response to treadmill graded exercise: traditional vs. underwater

The purpose of this study was to determine the metabolic effect(s) of four graded exercise tests (GXT) performed on the underwater treadmill (UWT), and compare them to the results from performing the standard Bruce protocol on a traditional land treadmill (LT). Twelve male Division I college athletes performed the stand Bruce protocol on a LT and 4 different GXT protocols on the UWT. Each test was performed to volitional max. oxygen consumption (VO2), heart rate (HR), respiratory exchange ratio (RER) and blood lactate (BL), which were measured at regular intervals throughout each of the GXTs. A two-way ANOVA with repeated measures was used to determine any main effect among the variables within the protocols and within the stages. Established effects were identified further using Tukey's post-hoc analysis. VO2and HR were positively correlated in all the GXTs, (r=0.992−0.999). When comparing the UWT GXTs to the Bruce, significant (P≤0.001) differences were found within certain stages for each of the dependent variables. While the Bruce resulted in attainment of VO2max, (mean = 55.72±5.92 ml/kg/min), only one of the UWT GXTs resulted in the same level of metabolic stress. At maximum speed and water velocity, the UWT produced a mean VO2of 53.9±3.68 ml/kg/min. HR and RER both increased by stage in all the GXTs as did BL. The onset of blood lactate accumulation (OBLA) was identified in all of the GXTs with the exception of one of the UWTs. Mean BL at OBLA ranged from, 3.12+1.31 to 5.98+4.24 mmol/dl. Our results suggest that an UWT GXT protocol can be developed that would produce metabolic results similar to the Bruce through stage 5. Buoyancy and variation in biomechanics need to be studied further for their effects on energy metabolism while performing work on the UWT. However, this study provides a better understanding of the metabolic demands at different treadmill speeds and water jet settings with the UWT.

Characterization of phytase from three ferns with differing arsenic tolerance

Phytase is involved in many physiological activities in plants including phosphorus metabolism and stress response. The effects of arsenic on phytase activities in arsenic-hyperaccumulator Pteris vittata were determined. Two arsenic-sensitive ferns (Pteris ensiformis and Nephrolepis exaltata) were included for comparison purpose. Fern phytase was extracted with Tris-HCl buffer (pH 7.6) followed by ammonium sulfate partial purification to characterize its properties and arsenic stress responses. The phytase showed an optimum pH of 5.0 and temperature of 40 °C except for P. vittata with 40-70 °C. Phytase from P. vittata was the first plant-phytase showing high heat resistance with no loss of activity by heating it at 70 °C, which may have application in feed industry. Phytase activity was inhibited by arsenate but not by arsenite. The fact that P. vittata phytase was the most heat-tolerant (40-70 °C) and had the highest resistance to arsenate among the three ferns suggest that phytase may play a role in arsenic detoxification and arsenic hyperaccumulation in P. vittata.

A phase II randomized four-regimen selection trial incorporating response for sequential chemotherapy in metastatic, unresectable urothelial cancer: Final results from the M. D. Anderson Cancer Center

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Background: We developed a clinical trial incorporating response into the treatment algorithm. Patients meeting a certain threshold of response continued with the same treatment; those with insufficient response were switched to alternative chemotherapy. We now report on final results from this trial. Methods: Patients were randomly assigned to one of four regimens: ifosfamide, doxorubicin, gemcitabine; ifosfamide, paclitaxel, cisplatin; gemcitabine, cisplatin; or cisplatin, gemcitabine, and ifosfamide. To continue with chemotherapy, patients must have had at least a 40% response after the first 6-week interval, and a >90% response after the second 6 weeks. Otherwise, they were re-randomized to alternate chemotherapy. Overall success (OSX) was defined as patients with a >90% response with either front-line or second-line therapy. Surgical consolidation was offered to patients at the discretion of their treating physician. Results: Median overall survival (OS) for 120 patients was 19.1 mo. (3 and 5-yr survival: 33% and 20%). OSX was achieved in 41 patients (median OS: 51 mo.); the median OS in the other 79 patients was 15 mo. (p = 0.0001), with a 5-yr survival of 42% and 10% respectively. Surgical consolidation was performed in 35 patients: 23 with nodal metastases to pelvic and/or RPLN, 6 with cT4b tumors, and an additional 6 patients with distant metastases. Their median OS from surgery was 23.7 months, (5-yr survival: 31%). Surgical consolidation in the setting of OSX was associated with a 42% 5-yr survival as compared to 11% in those undergoing surgery in the absence of OSX. Visceral metastases and poor performance status were associated with a worse prognosis. Conclusions: With sequential therapy, 34% of patients had a >90% response (OSX). A potential benefit in long-term survival was seen in patients who had surgical consolidation in the setting of OSX. This trial design provides a novel method for assessing the benefits of sequential chemotherapy, and enhancing the population of patients who may be offered surgical consolidation in the setting of initially unresectable, or metastatic urothelial cancer.

No significant financial relationships to disclose.