Unravelling species boundaries in the Aspergillus viridinutans complex (section Fumigati): opportunistic human and animal pathogens capable of interspecific hybridization.

Although Aspergillus fumigatus is the major agent of invasive aspergillosis, an increasing number of infections are caused by its cryptic species, especially A. lentulus and the A. viridinutans species complex (AVSC). Their identification is clinically relevant because of antifungal drug resistance and refractory infections. Species boundaries in the AVSC are unresolved since most species have uniform morphology and produce interspecific hybrids in vitro. Clinical and environmental strains from six continents (n = 110) were characterized by DNA sequencing of four to six loci. Biological compatibilities were tested within and between major phylogenetic clades, and ascospore morphology was characterised. Species delimitation methods based on the multispecies coalescent model (MSC) supported recognition of ten species including one new species. Four species are confirmed opportunistic pathogens; A. udagawae followed by A. felis and A. pseudoviridinutans are known from opportunistic human infections, while A. felis followed by A. udagawae and A. wyomingensis are agents of feline sino-orbital aspergillosis. Recently described human-pathogenic species A. parafelis and A. pseudofelis are synonymized with A. felis and an epitype is designated for A. udagawae. Intraspecific mating assay showed that only a few of the heterothallic species can readily generate sexual morphs in vitro. Interspecific mating assays revealed that five different species combinations were biologically compatible. Hybrid ascospores had atypical surface ornamentation and significantly different dimensions compared to parental species. This suggests that species limits in the AVSC are maintained by both pre- and post-zygotic barriers and these species display a great potential for rapid adaptation and modulation of virulence. This study highlights that a sufficient number of strains representing genetic diversity within a species is essential for meaningful species boundaries delimitation in cryptic species complexes. MSC-based delimitation methods are robust and suitable tools for evaluation of boundaries between these species.

Chimpanzee Personality and the Arginine Vasopressin Receptor 1A Genotype.

Polymorphisms of the arginine vasopressin receptor 1a (AVPR1a) gene have been linked to various measures related to human social behavior, including sibling conflict and agreeableness. In chimpanzees, AVPR1a polymorphisms have been associated with traits important for social interactions, including sociability, joint attention, dominance, conscientiousness, and hierarchical personality dimensions named low alpha/stability, disinhibition, and negative emotionality/low dominance. We examined associations between AVPR1a and six personality domains and hierarchical personality dimensions in 129 chimpanzees (Pan troglodytes) living in Japan or in a sanctuary in Guinea. We fit three linear and three animal models. The first model included genotype, the second included sex and genotype, and the third included genotype, sex, and sex × genotype. All personality phenotypes were heritable. Chimpanzees possessing the long form of the allele were higher in conscientiousness, but only in models that did not include the other predictors; however, additional analyses suggested that this may have been a consequence of study design. In animal models that included sex and sex × genotype, chimpanzees homozygous for the short form of the allele were higher in extraversion. Taken with the findings of previous studies of chimpanzees and humans, the findings related to conscientiousness suggest that AVPR1a may be related to lower levels of impulsive aggression. The direction of the association between AVPR1a genotype and extraversion ran counter to what one would expect if AVPR1a was related to social behaviors. These results help us further understand the genetic basis of personality in chimpanzees.

Glycolipid-based nanostructures with thermal-phase transition behavior functioning as solubilizers and refolding accelerators for protein aggregates.

The self-assembly of synthetic glycolipids produced nanostructures such as vesicles and nanotubes consisting of bilayer membranes, which underwent a gel-to-liquid crystalline thermal phase transition. Vesicles formed at temperatures above the thermal phase transition temperatures (Tg-l) could solubilize aggregates of denatured proteins by trapping them in the fluid bilayer membranes. Cooling to temperatures below Tg-l caused a morphological transformation into nanotubes that accompanied the thermal phase transition from the fluid to the solid state. This phenomenon allowed the trapped proteins to be quickly released into the bulk solution and simultaneously facilitated the refolding of the proteins. The refolding efficiency strongly depended on the electrostatic attraction between the bilayer membranes of the nanostructures and the proteins. Because of the long shape (>400 nm) of the nanotubes, simple membrane filtration through a pore size of 200 nm led to complete separation and recovery of the refolded proteins (3-9 nm sizes).

Should isolated peritoneal carcinomatosis from colorectal cancer be sub-classified into stage IVB in era of modern chemotherapy?

BACKGROUND: According to the 7th edition of the TNM staging system, stage IV metastatic colorectal cancer (CRC) at the time of initial diagnosis is sub-classified into stage IVA or IVB disease. Peritoneal carcinomatosis (PC), considered to have a dismal prognosis, is exclusively sub-classified into stage IVB, even though other metastases to a sole organ are sub-classified into stage IVA, which is considered to be associated with better survival. This retrospective study was undertaken to investigate the overall survival in metastatic CRC patients, focusing on PC patients. METHODS: We reviewed data on patients with metastatic CRC at initial diagnosis surgically treated between January 2006 and June 2011. A survival analysis was performed paying special attention to PC and sub-classifying patients with PC into three categories according to metastatic sites. RESULTS: There were 69 stage IVA patients (IVA group) and 83 stage IVB. Among stage IVB patients, 20 had isolated PC (PC-I group), 28 had PC with one or more other sites of metastasis (PC-II group), and 35 had at least 2 metastatic without peritoneal involvement (NPC group). Of 152 stage IV patients, 132 (87 %) underwent resection of the primary tumor and 19 (12 %) underwent radical resection of metastatic disease with microscopic free margins (R0 resection) including 5/20 (25 %) patients in the PC1 group. A total of 139 patients received oxaliplatin-based chemotherapy in a palliative (n = 125), neoadjuvant (n = 3), or adjuvant setting after R0 resection (n = 11). Compared with 36.6 months in the PC-I group, median survival was 32.5 months (P = 0.48) in the IVA group, 14.7 months (P = 0.07) in the PC-II group, and 12.9 months (P < 0.01) in the NPC group. CONCLUSIONS: The sub-classification of isolated PC into stage IVA instead of IVB might be more appropriate in the era of modern chemotherapy. Further investigation is warranted.

Molecular identification and thermoresistance to boiling of Nocardia farcinica and Nocardia cyriacigeorgica from bovine bulk tank milk.

Two strains of Nocardia spp. were isolated from bovine milk of two individual bulk tank. Molecular identification classified the strains as Nocardia farcinica and Nocardia cyriacigeorgica. The thermorresistance to boiling of the isolates was carried out and was observed bacterial growth after boiling. Our findings indicate the potential risk of pathogen transmission to humans through contaminated milk with Nocardia spp.

Propofol infusions using a human target controlled infusion (TCI) pump in chimpanzees (Pan troglodytes).

Chimpanzees are genetically and physiologically similar to humans. Several pharmacokinetic models of propofol are available and target controlled infusion (TCI) of propofol is established in humans, but not in chimpanzees. The purpose of this study was to investigate if human pharmacokinetic models can accurately predict propofol plasma concentration (Cp) in chimpanzees and if it is feasible to perform TCI in chimpanzees. Ten chimpanzees were anaesthetized for regular veterinary examinations. Propofol was used as an induction or maintenance agent. Blood samples were collected from a catheter in a cephalic vein at 3-7 time points between 1 and 100 min following the propofol bolus and/or infusion in five chimpanzees, or TCI in six chimpanzees. Cp was measured using high-performance liquid chromatography. The Marsh, Schnider and Eleveld human pharmacokinetic models were used to predict Cp for each case and we examined the predictive performances of these models using the Varvel criteria Median PE and Median APE. Median PE and Median APE for Marsh, Schnider and Eleveld models were within or close to the acceptable range. A human TCI pump was successfully maintained propofol Cp during general anesthesia in six chimpanzees. Human propofol pharmacokinetic models and TCI pumps can be applied in chimpanzees.

Tetraparesis resembling acute transverse myelitis in a captive chimpanzee (Pan troglodytes): long-term care and recovery.

BACKGROUND: A 24-year-old, male chimpanzee (Pan troglodytes) developed acute tetraparesis. Magnetic resonance imaging showed a diffuse T2-weighted hyperintensive lesion, indicating inflammation at the C1-2 level. All infective, autoimmune, and vascular investigations were unremarkable. RESULTS AND CONCLUSIONS: The chimpanzee's condition most resembled acute transverse myelitis (ATM) in humans. The chimpanzee was in severe incapacitated neurological condition with bedridden status and required 24-hour attention for 2 months followed by special care for over a year. Initially, corticosteroid therapy was performed, and his neurological symptoms improved to some extent; however, the general condition of the chimpanzee deteriorated in the first 6 months after onset. Pressure ulcers had developed at various areas on the animal's body, as the bedridden status was protracted. Supportive therapy was continued, and the general condition, appetite, mobility, and pressure ulcers have slowly but synergistically recovered over the course of 2 years.

The slow earthquake spectrum in the Japan Trench illuminated by the S-net seafloor observatories.

Investigating slow earthquake activity in subduction zones provides insight into the slip behavior of megathrusts, which can provide important clues about the rupture extent of future great earthquakes. Using the S-net ocean-bottom seismograph network along the Japan Trench, we mapped a detailed distribution of tectonic tremors, which coincided with very-low-frequency earthquakes and a slow slip event. Compiling these and other related observations, including repeating earthquakes and earthquake swarms, we found that the slow earthquake distribution is complementary to the Tohoku-Oki earthquake rupture. We used our observations to divide the megathrust in the Japan Trench into three along-strike segments characterized by different slip behaviors. We found that the rupture of the Tohoku-Oki earthquake, which nucleated in the central segment, was terminated by the two adjacent segments.

In situ Raman monitoring of dielectric-heating-enhanced freeze-drying under different electromagnetic wave frequencies.

We studied the effect of dielectric heating on the enhancement of freeze-drying by electromagnetic waves (EMWs) under different frequencies: 2.45 GHz microwaves (MWs), and 27 and 200 MHz radio frequencies (RFs). The irradiation with RFs, particularly at 27 MHz, reduced the duration of freeze-drying by 67%. We further analysed the water structure by in situ Raman spectroscopy during freeze-drying under EMWs. The phase transition from ice to water occurred soon after starting irradiation by MWs at 2.45 GHz, while the ice phase was almost maintained at an RF of 27 MHz.

Stable confinement of nanosecond laser pulse in an enhancement cavity.

We present a technique that enhances the intensity of a nanosecond laser pulse by confining it in an enhancement cavity. The point of the technique is that a weak continuous-wave laser radiation, locked to the enhancement cavity, is injected into a nanosecond injection-locked pulsed laser as a seed. This leads to a stable confinement of the nanosecond pulse in the enhancement cavity. It is demonstrated that the pulsed intensity is enhanced by a factor of 120 for a 40-ns pulse, consistent with the theoretical prediction.

Fluid-structure interaction in layered aortic arch aneurysm model: assessing the combined influence of arch aneurysm and wall stiffness.

The patients with aortic aneurysm, especially aortic arch aneurysm, are prone to have aortic dissection. For investigation of the effect of aneurysm and wall stiffness on wall stress distribution, both the nonaneurysm arch model and the aneurysm arch model are constructed. The fluid structure interaction in the arch model of aorta was implemented. The results show the stresses are much higher at inflection points in aneurysm model than in nonaneurysm model, and the stresses at media in stiffened wall are higher than in unstiffened wall. The high composite stress is located at inflection points and is much higher in aneurysm model. The arch aneurysm and wall stiffening are important determinants of peak wall stress in aortic wall.

Purification and characterization of pyrroline-5-carboxylate reductase from bovine retina.

Bovine retinal pyrroline-5-carboxylate reductase (L-proline: NAD(P)+ 5-oxidoreductase, EC 1.5.1.2) was purified 180-fold from crude extract, using affinity chromatography with 2',5'-ADP Sepharose 4B. The purified enzyme utilized either NADH or NADPH as the coenzyme. The enzyme activity was inhibited with ATP, and activated with potassium and phosphate ions, suggesting that it may be regulated by the energy level and the redox state in the retina. The distribution of this enzyme in bovine lens suggests a developmental trail of the enzyme in the lens.

delta 1-Pyrroline-5-carboxylate reductase from Baker's yeast. Purification, properties and its application in the assays of L-delta 1-pyrroline-5-carboxylate and L-ornithine in tissue.

delta 1-Pyrroline-5-carboxylate reductase (L-proline:NAD(P)+ 5-oxidoreductase, EC 1.5.1.2) from Baker's yeast has been purified and characterized. Purification to an apparently homogenous protein was effected by using 'reagent-grade' water containing dithiothreitol and by maintaining a constant pH 7.5, because of the instability of the enzyme protein. The enzyme was purified approximately 200-fold from the crude extract of baker's yeast, and it is a negatively-charged protein with a molecular weight of 125 000, containing an active SH group which participates in binding with NAD(P)H. The Km value for DL-pyrroline-5-carboxylate is 0.8 x 10(-4) M; for NADH, it is 4.8 x 10(-5) M; and for NADPH, it is 5.6 x 10(-5) M. These Km values are much smaller than those of enzymes from other sources. The purified enzyme is free of contaminating enzymes which might interfere with its use in assays. The enzyme has been applied successfully to the assays of L-delta 1-pyrroline-5-carboxylate and L-ornithine in tissue, and in vivo levels of these amino acids in rat liver are reported.

Delta 1-pyrroline-5-carboxylate reductase from baker's yeast: further purification by affinity chromatography with 5' AMP-Sepharose 4B.

A homogeneous preparation of delta 1-pyrroline-5-carboxylate reductase (L-proline: NAD (P)+ 5-oxidoreductase, EC 1.5.1.2) was obtained from baker's yeast by an affinity chromatography, using 5' AMP-Sepharose 4B. After the 1st DEAE-Sephadex column chromatography, the enzyme absorbed on 5' AMP-Sepharose column was eluted with 1 mM ATP. The final preparation was homogeneous on polyacrylamide gel electrophoresis and purified 3500-fold from the crude extract. This purified enzyme was very useful as a coupling enzyme for the assays of ornithine and pyrroline-5-carboxylate in tissues, and for the rate assay of ornithine aminotransferase activity.

The characterization of a UDP-N-acetylglucosamine: Gal beta 1-4Glc(NAc) beta 1-3 N-acetylglucosaminyltransferase in fluids from rat rete testis.

Using Gal beta 1-4GlcNAc or Gal beta 1-4Glc as substrates, the UDP-N-acetylglucosamine: Gal beta 1-4Glc(NAc) beta 1-3-N-acetylglucosaminyltransferase (GlcNAcTase) activity of rat rete testicular fluid was investigated with respect to the effects of pH and of divalent metal ions, apparent Km value, acceptor specificity and identity of products. The enzyme, whose activity was dependent absolutely on the presence of Mn2+, had an optimum pH of 7.5. It was completely inhibited by EDTA, Zn2+ and gossypol, and partially by Co2+ and Ca2+. Triton X-100 (1%) had no effect. When several oligosaccharides were tested as acceptors, the highest affinity was found with Gal beta 1-3[Gal beta 1-4GlcNAc beta 1-6]Gal beta 1-4Glc. With Gal beta 1-4Glc as acceptor, the product was identified from its 1H-NMR spectrum as GlcNAc beta 1-3Gal beta 1-4Glc (lacto-N-triose II) by reference to the spectrum of authentic lacto-N-triose II. Both testicular and epididymal fluids showed GlcNAcTase activity. In epididymis the specific activity increased gradually from the proximal caput to the proximal cauda.

Microheterogeneity and intrahepatic localization of human and rat liver cytosolic alanine aminotransferase.

Native human cytosolic alanine aminotransferase (EC 2.6.1.2) was found to be a homodimer consisting of two 55 kDa subunits. The human enzyme was more cationic and more susceptible to heat inactivation and heavy metal-inhibition than its rat homologue. Isoelectric focussing separated three human isoforms and four rat isoforms of cALT that differed in their isoelectric points. Two subtypes of the enzyme which differed in apparent molecular weight on sodium dodecylsulfate polyacrylamide gel electrophoresis were detected in rat, the liver type and the muscular type. This microheterogeneity was not found for human cytosolic alanine aminotransferase. Immunohistochemical studies revealed that the rat liver enzyme was exclusively localized in periportal hepatocytes, consistent with its role in gluconeogenesis. In human hepatocytes the plasma membrane was intensely stained, implicating an intracellular localization near the plasma membrane.

Ornithine oxoacid aminotransferase found in AH 130 ascites hepatoma cells.

We found heterogenous ornithine oxoacid aminotransferase (L-ornithine: 2-oxo-acid aminotransferase, EC 2.6.1.1.3) in rat ascites hepatoma AH 130 cells. Compared with enzymes from normal rat tissues, this heterogenous enzyme showed larger Km values for 2-oxoglutarate, a different elution-profile upon affinity chromatography with 2-oxoglutarate, more anionic mobility upon polyacrylamide gell electrophoresis, and a clearly different salting-out property upon ammonium sulfate fractionation. Similar heterogeneity of this aminotransferase was found in human cancer cells.

Nasal absorption of insulin in dogs.

The intranasal application of an insulin solution in dogs resulted in the rise of plasma immunoreactive insulin and in dose-dependent hypoglycemia. The absorption of insulin from this site was found to be enhanced when insulin was dissolved in an acid medium. In addition, when an insulin preparation with some surfactant was used, the effectiveness of nasally administered insulin was 25 to 30 per cent of that achieved with intravenously administered insulin.

Measurement of the ratio of cerebral oxygen consumption to glucose utilization by positron emission tomography: its consistency with the values determined by the Kety-Schmidt method in normal volunteers.

The regional interrelationship between cerebral oxygen consumption (CMRO2) and cerebral glucose utilization (CMRGlc) was studied in normal subjects using positron emission tomography (PET) and the 15O steady-state inhalation and the [18F]fluoro deoxyglucose method. The use of standard sets of rate constants and the model lumped constant of 0.52 as well as the regional blood-brain partition coefficient for water and the blood volume correction for oxygen extraction fraction provided a CMRO2/CMRGlc ratio of 4.89 in the cortical gray matter, 5.27 in the basal ganglia and 5.82 in the centrum semiovale (white matter). The values of CMRO2/CMRGlc for the basal ganglia and the white matter were consistent with those reported for the whole brain with the Kety-Schmidt method. There was no significant difference in the CMRO2/CMRGlc between the basal ganglia and the white matter indicating the similar nature of in vivo oxidative metabolism of glucose in neuron-rich region and glial cell-rich region.

Positron emission tomography in minor ischemic stroke using oxygen-15 steady-state technique.

A study with positron emission tomography (PET) was performed on 10 patients with ischemic stroke and mild disability. The patients underwent cerebral angiography, x-ray computed tomography (CT) scan and regional cerebral measurements of CBF, CMRO2, oxygen extraction ratio (OER), and cerebral blood volume (CBV). Only minor arterial involvement was detected by angiography. In all patients, PET images of functional defects were more extensive than the corresponding CT hypodensity, and there were statistically significant reductions in CBF, CMRO2, and CBF/CBV ratio as compared with control subjects. Half of the regions analyzed in the affected hemisphere demonstrated a disruption of the normal coupling between CBF and CMRO2 as reflected by OER values significantly higher or lower than those of the corresponding region of the contralateral hemisphere. The pathophysiological pattern of high OER combined with a reduction in CBF proportionally greater than the reduction in CMRO2 was particularly indicative of regional chronic hemodynamic compromise in these patients.