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BACKGROUND: IGTS is a rare phenomenon of paradoxical germ cell tumor (GCT) growth during or following treatment despite normalization of tumor markers. We sought to evaluate the frequency, clinical characteristics and outcome of IGTS in patients in 21 North-American and Australian institutions. METHODS: Patients with IGTS diagnosed from 2000-2017 were retrospectively evaluated. RESULTS: Out of 739 GCT diagnoses, IGTS was identified in 33 patients (4.5%). IGTS occurred in 9/191 (4.7%) mixed-malignant GCTs, 4/22 (18.2%) immature teratomas (ITs), 3/472 (0.6%) germinomas/germinomas with mature teratoma, and in 17 secreting non-biopsied tumours. Median age at GCT diagnosis was 10.9 years (range 1.8-19.4). Male gender (84%) and pineal location (88%) predominated. Of 27 patients with elevated markers, median serum AFP and Beta-HCG were 70 ng/mL (range 9.2-932) and 44 IU/L (range 4.2-493), respectively. IGTS occurred at a median time of 2 months (range 0.5-32) from diagnosis, during chemotherapy in 85%, radiation in 3%, and after treatment completion in 12%. Surgical resection was attempted in all, leading to gross total resection in 76%. Most patients (79%) resumed GCT chemotherapy/radiation after surgery. At a median follow-up of 5.3 years (range 0.3-12), all but 2 patients are alive (1 succumbed to progressive disease, 1 to malignant transformation of GCT). CONCLUSION: IGTS occurred in less than 5% of patients with GCT and most commonly after initiation of chemotherapy. IGTS was more common in patients with IT-only on biopsy than with mixed-malignant GCT. Surgical resection is a principal treatment modality. Survival outcomes for patients who developed IGTS are favourable.
The structure of a series of lanthanide iron cobalt perovskite oxides, R(Fe0.5Co0.5)O3 (R = Pr, Nd, Sm, Eu, and Gd), have been investigated. The space group of these compounds was confirmed to be orthorhombic Pnma (No. 62), Z = 4. From Pr to Gd, the lattice parameter a varies from 5.466 35(13) Å to 5.507 10(13) Å, b from 7.7018(2) to 7.561 75(13) Å, c from 5.443 38(10) to 5.292 00(8) Å, and unit-cell volume V from 229.170(9) Å3 to 220.376(9) Å3, respectively. While the trend of V follows the trend of the lanthanide contraction, the lattice parameter “a” increases as the ionic radius r(R3+) decreases. X-ray diffraction (XRD) and transmission electron microscopy confirm that Fe and Co are disordered over the octahedral sites. The structure distortion of these compounds is evidenced in the tilt angles θ, ϕ, and ω, which represent rotations of an octahedron about the pseudocubic perovskite p, p, and p axes. All three tilt angles increase across the lanthanide series (for R = Pr to R = Gd: θ increases from 12.3° to 15.2°, ϕ from 7.5° to 15.8°, and ω from 14.4° to 21.7°), indicating a greater octahedral distortion as r(R3+) decreases. The bond valence sum for the sixfold (Fe/Co) site and the eightfold R site of R(Fe0.5Co0.5)O3 reveal no significant bond strain. Density Functional Theory calculations for Pr(Fe0.5Co0.5)O3 support the disorder of Fe and Co and suggest that this compound to be a narrow band gap semiconductor. XRD patterns of the R(Fe0.5Co0.5)O3 samples were submitted to the Powder Diffraction File.
During the past three years radiocarbon assay has emerged as a primary tool in the quantitative assignment of sources of urban and rural particulate pollution. Its use in several major field studies has come about because of its excellent (fossil/biogenic) discriminating power, because of advances in 14C measurements of small samples, and because of the increased significance of carbonaceous particles in the atmosphere. The problem is especially important in the cities, where increased concentrations of fine particles lead to pollution episodes characterized by poor visibility and changes in the radiation balance (absorption, scattering), and immediate and possibly long-term health effects. Efforts in source apportionment in such affected areas have been based on emissions inventories, dispersion modeling, and receptor modeling – ie, chemical and physical (and statistical) characterization of particles collected at designated receptor sites. It is in the last category that 14C has become quite effective in helping to resolve particle sources. Results are presented for studies carried out in Los Angeles, Denver, and Houston which incorporated 14C measurements, inorganic and organic chemical characterization, and receptor modeling. The 14C data indicated wide ranging contributions of biogenic and fossil carbon sources – eg, <10% to 60% contemporary (biogenic) in Houston – depending on meteorological, biological, and anthropological activity. The combined (chemical, isotopic, statistical) data point to sources such as vehicles, wood combustion, power plants, and vegetation.
In this paper we report the first characterization of cultivable bacteria obtained from the Antarctic sea urchin Sterechinus neumayeri. The coelomic fluid was obtained from a pool of sea urchins which was plated onto different media to isolate the bacteria. A total of 42 isolates of psychrotrophic and aerobic γ-Proteobacteria (59.5%), Flavobacteria (33.3%) and Actinomycetes (7.2%) were isolated and sequenced. These bacteria were exposed to heavy metals and antibiotics, where 38 strains were analysed by the minimal inhibitory concentration method. Antibiotic resistance was detected in 44% of cultivable strains, and a further 13% presented co-resistance to antibiotics and heavy metals. The genera of bacteria that showed an increased resistance and co-resistance to metals and antibiotics were Flavobacterium, Psychrobacter and Pseudomonas. Additionally, 30.9% of isolated bacterial strains contained plasmids, which are probably related to resistance and co-resistance to metals. These results indicate that sea urchin-associated bacteria could be reservoirs for antibiotic resistance genes.
Hospital-acquired methicillin-resistant Staphylococcus aureus (HA-MRSA) is becoming increasingly established in Asian hospitals. The primary aim of this study was to decompose the risk factors for HA-MRSA based on conceptual clinical pathways. The secondary aim was to show the amount of effect attributable to antibiotic exposure and total length of stay before outcome (LBO) so that institutions can manage at-risk patients accordingly. A case-control study consisting of 1200 inpatients was conducted in a large tertiary hospital in Singapore between January and December 2006. Results from the generalized structural equation model (GSEM) show that LBO [adjusted odds ratio (aOR) 14·9, 95% confidence interval (CI) 8·7–25·5], prior hospitalization (aOR 6·2, 95% CI 3·3–11·5), and cumulative antibiotic exposure (aOR 3·5, 95% CI 2·3–5·3), directly affected HA-MRSA acquisition. LBO accounted for the majority of the effects due to age (100%), immunosuppression (67%), and surgery (96%), and to a lesser extent for male gender (22%). Our model enabled us to account and quantify effects of intermediaries. LBO was found to be an important mediator of age, immunosuppression and surgery on MRSA infection. Traditional regression approaches will not only give different conclusions but also underestimate the effects. Hospitals should minimize the hospital stay when possible to reduce the risk of MRSA.
To identify predictive factors and mortality of patients with influenza admitted to intensive care units (ICU) we carried out a prospective cohort study of patients hospitalized with laboratory-confirmed influenza in adult ICUs in a network of Canadian hospitals between 2006 and 2012. There were 626 influenza-positive patients admitted to ICUs over the six influenza seasons, representing 17·9% of hospitalized influenza patients, 3·1/10 000 hospital admissions. Variability occurred in admission rate and proportion of hospital influenza patients who were admitted to ICUs (proportion range by year: 11·7–29·4%; 21·3% in the 2009–2010 pandemic). In logistic regression models ICU patients were younger during the pandemic and post-pandemic period, and more likely to be obese than hospital non-ICU patients. Influenza B accounted for 14·2% of all ICU cases and had a similar ICU admission rate as influenza A. Influenza-related mortality was 17·8% in ICU patients compared to 2·0% in non-ICU patients.
X-ray structural characterization and X-ray reference powder patterns have been determined for two series of iron- and cobalt-containing layered compounds (BaxSr1−x)2Co2Fe12O22 (x = 0.2, 0.4, 0.6, 0.8) and (BaxSr1−x)Co2Fe16O27 (x = 0.2, 0.4, 0.6, 0.8). The (BaxSr1−x)2Co2Fe12O22 series of compounds crystallized in the space group R
m (No. 166), with Z = 3. The structure is essentially that of the Y-type hexagonal ferrite, BaM2+Fe63+O11. The lattice parameters range from a = 5.859 15(8) to 5.843 72(8) Å, and c = 43.4975(9) to 43.3516(9) Å for x = 0.2 to 0.8, respectively. The (BaxSr1−x)Co2Fe16O27 series (W-type hexagonal ferrite) crystallized in the space group P63/mmc (No. 194) and Z = 2. The lattice parameters range from a = 5.902 05(12) to 5.8979(2) Å and c = 32.9002(10) to 32.8110(13) Å for x = 0.2 to 0.8. Results of measurements of the Seebeck coefficient and resistivity of these two sets of samples indicated that they are insulators. Powder X-ray diffraction patterns of these two series of compounds have been submitted to be included in the Powder Diffraction File.
In August 2011, one of the earliest cases of influenza A(H3N2) variant [A(H3N2)v] virus infection was hospitalized with severe illness. To investigate the potential for healthcare-associated transmission of influenza A(H3N2)v, we evaluated both healthcare providers and patient contacts of the case. We found that healthcare-associated transmission was unlikely.
This case report describes the endoscopic transsphenoidal management of a cholesterol granuloma situated in a technically challenging part of the petrous apex, and the associated peri- and post-operative complications that arose. The literature on diagnosis and management of petrous apex cholesterol granulomas is reviewed.
Method and results:
Surgical intervention was attempted on three occasions, each time via an endoscopic, transsphenoidal approach with image guidance. The procedure was abandoned on the first occasion as there was a significant risk to the carotid artery; only a small drainage ostium was created because of the proximity of the carotid artery. The second attempt, complicated by copious bleeding from the clival venous plexus, was arrested prematurely. Successful drainage was achieved at the third attempt, but recovery was complicated by tension pneumocephalus.
The transnasal route is less invasive than a lateral labyrinthine or cochlear approach, and spares cochlear and vestibular function. However, this approach is not without risk. It is important to consider the natural anatomical variance of vasculature when planning surgical intervention for a lesion situated in a technically challenging part of the petrous apex. Additional magnetic resonance venography is recommended to circumnavigate the venous plexus, thereby avoiding an unexpected breach.
The cold, dry, and stable air above the summits of the Antarctic plateau provides the best ground-based observing conditions from optical to sub-millimetre wavelengths to be found on the Earth. Pathfinder for an International Large Optical Telescope (PILOT) is a proposed 2 m telescope, to be built at Dome C in Antarctica, able to exploit these conditions for conducting astronomy at optical and infrared wavelengths. While PILOT is intended as a pathfinder towards the construction of future grand-design facilities, it will also be able to undertake a range of fundamental science investigations in its own right. This paper provides the performance specifications for PILOT, including its instrumentation. It then describes the kinds of projects that it could best conduct. These range from planetary science to the search for other solar systems, from star formation within the Galaxy to the star formation history of the Universe, and from gravitational lensing caused by exo-planets to that produced by the cosmic web of dark matter. PILOT would be particularly powerful for wide-field imaging at infrared wavelengths, achieving near diffraction-limited performance with simple tip–tilt wavefront correction. PILOT would also be capable of near diffraction-limited performance in the optical wavebands, as well be able to open new wavebands for regular ground-based observation, in the mid-IR from 17 to 40 μm and in the sub-millimetre at 200 μm.
Major depressive disorder (MDD) and generalized anxiety disorder (GAD) have the highest co-morbidity rates within the internalizing disorders cluster, yet no Internet-based cognitive behavioural therapy (iCBT) programme exists for their combined treatment.
We designed a six-lesson therapist-assisted iCBT programme for mixed anxiety and depression. Study 1 was a randomized controlled trial (RCT) comparing the iCBT programme (n = 46) versus wait-list control (WLC; n = 53) for patients diagnosed by structured clinical interview with MDD, GAD or co-morbid GAD/MDD. Primary outcome measures were the Patient Health Questionnaire nine-item scale (depression), Generalized Anxiety Disorder seven-item scale (generalized anxiety), Kessler 10-item Psychological Distress scale (distress) and 12-item World Health Organization Disability Assessment Schedule II (disability). The iCBT group was followed up at 3 months post-treatment. In study 2, we investigated the adherence to, and efficacy of the same programme in a primary care setting, where patients (n = 136) completed the programme under the supervision of primary care clinicians.
The RCT showed that the iCBT programme was more effective than WLC, with large within- and between-groups effect sizes found (>0.8). Adherence was also high (89%), and gains were maintained at 3-month follow-up. In study 2 in primary care, adherence to the iCBT programme was low (41%), yet effect sizes were large (>0.8). Of the non-completers, 30% experienced benefit.
Together, the results show that iCBT is effective and adherence is high in research settings, but there is a problem of adherence when translated into the ‘real world’. Future efforts need to be placed on developing improved adherence to iCBT in primary care settings.
Cognitive impairment is a core feature of schizophrenia. Its relationship with duration of untreated psychosis (DUP), a potentially malleable prognostic factor, has been less studied, with inconsistent findings being observed in the literature. Previous research investigating such a relationship was mostly cross-sectional and none of those prospective studies had a follow-up duration beyond 2 years.
A total of 93 Hong Kong Chinese aged 18 to 55 years presenting with first-episode schizophrenia-spectrum disorder were studied. DUP and pre-morbid adjustment were measured using a structured interview incorporating multiple sources of information. Psychopathological evaluation was administered at intake, after clinical stabilization of the first psychotic episode, and at 12, 24 and 36 months. Cognitive functions were measured at clinical stabilization, and at 12, 24 and 36 months.
DUP exerted differential effects on various cognitive domains, with memory deficits being the most related to DUP even when potential confounders including pre-morbid adjustment and sex were adjusted. Prolonged DUP was associated with more severe impairment in visual memory at clinical stabilization and verbal memory at 24 and 36 months. Further, patients with a long DUP were found to have worse outcomes on negative symptoms at 36 months. The effects of DUP on verbal memory remained significant even when negative symptoms were taken into consideration.
Our findings provided further supportive evidence that delayed treatment to first-episode psychosis is associated with poorer cognitive and clinical outcomes. In addition, DUP may specifically affect memory function and its adverse impact on verbal memory may only become evident at a later stage of the recovery process.