Soil organic carbon is not just for soil scientists: measurement recommendations for diverse practitioners.

Soil organic carbon (SOC) regulates terrestrial ecosystem functioning, provides diverse energy sources for soil microorganisms, governs soil structure, and regulates the availability of organically bound nutrients. Investigators in increasingly diverse disciplines recognize how quantifying SOC attributes can provide insight about ecological states and processes. Today, multiple research networks collect and provide SOC data, and robust, new technologies are available for managing, sharing, and analyzing large data sets. We advocate that the scientific community capitalize on these developments to augment SOC data sets via standardized protocols. We describe why such efforts are important and the breadth of disciplines for which it will be helpful, and outline a tiered approach for standardized sampling of SOC and ancillary variables that ranges from simple to more complex. We target scientists ranging from those with little to no background in soil science to those with more soil-related expertise, and offer examples of the ways in which the resulting data can be organized, shared, and discoverable.

Taxonomic Interference Associated with Phonemic Paraphasias in Agrammatic Primary Progressive Aphasia.

Phonemic paraphasias are thought to reflect phonological (post-semantic) deficits in language production. Here we present evidence that phonemic paraphasias in non-semantic primary progressive aphasia (PPA) may be associated with taxonomic interference. Agrammatic and logopenic PPA patients and control participants performed a word-to-picture visual search task where they matched a stimulus noun to 1 of 16 object pictures as their eye movements were recorded. Participants were subsequently asked to name the same items. We measured taxonomic interference (ratio of time spent viewing related vs. unrelated foils) during the search task for each item. Target items that elicited a phonemic paraphasia during object naming elicited increased taxonomic interference during the search task in agrammatic but not logopenic PPA patients. These results could reflect either very subtle sub-clinical semantic distortions of word representations or partial degradation of specific phonological word forms in agrammatic PPA during both word-to-picture matching (input stage) and picture naming (output stage). The mechanism for phonemic paraphasias in logopenic patients seems to be different and to be operative at the pre-articulatory stage of phonological retrieval. Glucose metabolic imaging suggests that degeneration in the left posterior frontal lobe and left temporo-parietal junction, respectively, might underlie these different patterns of phonemic paraphasia.

Active lifestyles moderate clinical outcomes in autosomal dominant frontotemporal degeneration.

INTRODUCTION: Leisure activities impact brain aging and may be prevention targets. We characterized how physical and cognitive activities relate to brain health for the first time in autosomal dominant frontotemporal lobar degeneration (FTLD). METHODS: A total of 105 mutation carriers (C9orf72/MAPT/GRN) and 69 non-carriers reported current physical and cognitive activities at baseline, and completed longitudinal neurobehavioral assessments and brain magnetic resonance imaging (MRI) scans. RESULTS: Greater physical and cognitive activities were each associated with an estimated >55% slower clinical decline per year among dominant gene carriers. There was also an interaction between leisure activities and frontotemporal atrophy on cognition in mutation carriers. High-activity carriers with frontotemporal atrophy (-1 standard deviation/year) demonstrated >two-fold better cognitive performances per year compared to their less active peers with comparable atrophy rates. DISCUSSION: Active lifestyles were associated with less functional decline and moderated brain-to-behavior relationships longitudinally. More active carriers "outperformed" brain volume, commensurate with a cognitive reserve hypothesis. Lifestyle may confer clinical resilience, even in autosomal dominant FTLD.

Prominent microglial activation in cortical white matter is selectively associated with cortical atrophy in primary progressive aphasia.

AIMS: Primary progressive aphasia (PPA) is a clinical syndrome characterized by selective language impairments associated with focal cortical atrophy favouring the language dominant hemisphere. PPA is associated with Alzheimer's disease (AD), frontotemporal lobar degeneration (FTLD) and significant accumulation of activated microglia. Activated microglia can initiate an inflammatory cascade that may contribute to neurodegeneration, but their quantitative distribution in cortical white matter and their relationship with cortical atrophy remain unknown. We investigated white matter activated microglia and their association with grey matter atrophy in 10 PPA cases with either AD or FTLD-TDP pathology. METHODS: Activated microglia were quantified with optical density measures of HLA-DR immunoreactivity in two regions with peak cortical atrophy, and one nonatrophied region within the language dominant hemisphere of each PPA case. Nonatrophied contralateral homologues of the language dominant regions were examined for hemispheric asymmetry. RESULTS: Qualitatively, greater densities of activated microglia were observed in cortical white matter when compared to grey matter. Quantitative analyses revealed significantly greater densities of activated microglia in the white matter of atrophied regions compared to nonatrophied regions in the language dominant hemisphere (P < 0.05). Atrophied regions of the language dominant hemisphere also showed significantly more activated microglia compared to contralateral homologues (P < 0.05). CONCLUSIONS: White matter activated microglia accumulate more in atrophied regions in the language dominant hemisphere of PPA. While microglial activation may constitute a response to neurodegenerative processes in white matter, the resultant inflammatory processes may also exacerbate disease progression and contribute to cortical atrophy.

Major venom proteins of the fire ant Solenopsis invicta: insights into possible pheromone-binding function from mass spectrometric analysis.

Proteins in the venom of the fire ant Solenopsis invicta have been suggested to function in pheromone binding. Venom from queens and workers contains different isoforms of these proteins, consistent with the differing pheromones they secrete, but questions remain about the venom protein composition and glandular source. We found that the queen venom contains a previously uncharacterized pheromone-binding protein paralogue known as Sol i 2X1. Using imaging mass spectrometry, we located the main venom proteins in the poison sac, implying that pheromones might have to compete with venom alkaloids for binding. Using the known structure of the worker venom protein Sol i 2w, we generated three-dimensional homology models of the worker venom protein Sol i 4.02, and of the two main venom proteins in queens and female alates, Sol i 2q and Sol i 2X1. Surprisingly, the models show that the proteins have relatively small internal hydrophobic binding pockets that are blocked by about 10 amino acids of the C-terminal region. For these proteins to function as carriers of hydrophobic ligands, a conformational change would be required to displace the C-terminal region, somewhat like the mechanism known to occur in the silk moth pheromone-binding protein.

Association between lateral patellar osteoarthrosis and knee morphology and alignment in young adults.

AIM: To assess whether patellar and trochlea morphology and patellar alignment are associated with lateral patellar osteoarthrosis/chondrosis (OAC) in young adults. MATERIALS AND METHODS: Magnetic resonance imaging (MRI) images of 183 subjects (81 cases, 102 controls) aged 21-35 years of age were evaluated. Quantitative measurements of patella and trochlea morphology and patellar alignment were obtained. Axial and sagittal MRI images were reviewed to grade the severity of focal cartilage defects along the lateral facet of the patella. Controls had knees without any abnormalities and were compared to cases with mild and severe lateral patellar OAC. Multivariable logistic regression was used to assess associations between measurements and lateral patellar OAC adjusting for body mass index. RESULTS: Cases were more likely to have higher Insall-Salvati ratios (OR=350; p<0.001), shorter ratios of the medial to lateral facets of the patella (OR=1.63×10-3; p<0.001), a shallower (angle closer to 180°) median eminence of the patella (OR=1.063; p=0.009), decreased trochlear cartilage overlap with the patellar cartilage (OR=0.086; p=0.023), and a less angulated lateral patellofemoral angle (OR=0.903; p=0.028), compared to controls. Cases were also more likely to have patellar tendinosis (OR=5.265; p=0.045) and oedema in the superolateral aspect of Hoffa's fat pad (OR=9.872; p<0.001). CONCLUSION: Patellar and trochlear morphology and patellar alignment are associated with lateral patellofemoral compartment OAC in young adults.

Predicting Brain Amyloid Status Using the National Institute of Health Toolbox (NIHTB) for Assessment of Neurological and Behavioral Function.

BACKGROUND: Amyloid-beta (Aß) plaque is a neuropathological hallmark of Alzheimer's disease (AD). As anti-amyloid monoclonal antibodies enter the market, predicting brain amyloid status is critical to determine treatment eligibility. OBJECTIVE: To predict brain amyloid status utilizing machine learning approaches in the Advancing Reliable Measurement in Alzheimer's Disease and Cognitive Aging (ARMADA) study. DESIGN: ARMADA is a multisite study that implemented the National Institute of Health Toolbox for Assessment of Neurological and Behavioral Function (NIHTB) in older adults with different cognitive ability levels (normal, mild cognitive impairment, early-stage dementia of the AD type). SETTING: Participants across various sites were involved in the ARMADA study for validating the NIHTB. PARTICIPANTS: 199 ARMADA participants had either PET or CSF information (mean age 76.3 ± 7.7, 51.3% women, 42.3% some or complete college education, 50.3% graduate education, 88.9% White, 33.2% with positive AD biomarkers). MEASUREMENTS: We used cognition, emotion, motor, sensation scores from NIHTB, and demographics to predict amyloid status measured by PET or CSF. We applied LASSO and random forest models and used the area under the receiver operating curve (AUROC) to evaluate the ability to identify amyloid positivity. RESULTS: The random forest model reached AUROC of 0.74 with higher specificity than sensitivity (AUROC 95% CI:0.73 - 0.76, Sensitivity 0.50, Specificity 0.88) on the held-out test set; higher than the LASSO model (0.68 (95% CI:0.68 - 0.69)). The 10 features with the highest importance from the random forest model are: picture sequence memory, cognition total composite, cognition fluid composite, list sorting working memory, words-in-noise test (hearing), pattern comparison processing speed, odor identification, 2-minutes-walk endurance, 4-meter walk gait speed, and picture vocabulary. Overall, our model revealed the validity of measurements in cognition, motor, and sensation domains, in associating with AD biomarkers. CONCLUSION: Our results support the utilization of the NIH toolbox as an efficient and standardizable AD biomarker measurement that is better at identifying amyloid negative (i.e., high specificity) than positive cases (i.e., low sensitivity).

Choline content of rat brain.

The free choline concentration in the rat brain was found to be 26.3 nanomoles per gram of brain tissue. This value was obtained through use of 6-second microwave irradiation for killing animals and inactivating enzymes, followed by a pyrolysis-gas chromatographic assay procedure. The identities of compounds measured from brain samples were verified by mass spectrometry.

A potential noninvasive neurobiological test for Alzheimer's disease.

Currently Alzheimer's disease, which affects more than 20 million people worldwide, can only be definitely diagnosed by histological examination of brain tissue obtained at autopsy or biopsy. There is a great need for an early, noninvasive, sensitive, and easily administered diagnostic test of Alzheimer's disease. Here it is reported that patients diagnosed with probable Alzheimer's disease by standard clinical criteria exhibited a marked hypersensitivity in their pupil dilation response to a cholinergic antagonist, tropicamide, placed in their eyes. It was possible to distinguish 18 of 19 individuals (95%) either clinically diagnosed with Alzheimer's disease or classified as suspect Alzheimer's individuals by neuropsychological screening from 30 of 32 normal elderly controls (94%).

2019 Frank Stinchfield Award: A comparison of prosthetic joint infection rates between direct anterior and non-anterior approach total hip arthroplasty.

AIMS: We studied the impact of direct anterior (DA) versus non-anterior (NA) surgical approaches on prosthetic joint infection (PJI), and examined the impact of new perioperative protocols on PJI rates following all surgical approaches at a single institution. PATIENTS AND METHODS: A total of 6086 consecutive patients undergoing primary total hip arthroplasty (THA) at a single institution between 2013 and 2016 were retrospectively evaluated. Data obtained from electronic patient medical records included age, sex, body mass index (BMI), medical comorbidities, surgical approach, and presence of deep PJI. There were 3053 male patients (50.1%) and 3033 female patients (49.9%). The mean age and BMI of the entire cohort was 62.7 years (18 to 102, sd 12.3) and 28.8 kg/m2 (13.3 to 57.6, sd 6.1), respectively. Infection rates were calculated yearly for the DA and NA approach groups. Covariates were assessed and used in multivariate analysis to calculate adjusted odds ratios (ORs) for risk of development of PJI with DA compared with NA approaches. In order to determine the effect of adopting a set of infection prevention protocols on PJI, we calculated ORs for PJI comparing patients undergoing THA for two distinct time periods: 2013 to 2014 and 2015 to 2016. These periods corresponded to before and after we implemented a set of perioperative infection protocols. RESULTS: There were 1985 patients in the DA group and 4101 patients in the NA group. The overall rate of PJI at our institution during the study period was 0.82% (50/6086) and decreased from 0.96% (12/1245) in 2013 to 0.53% (10/1870) in 2016. There were 24 deep PJIs in the DA group (1.22%) and 26 deep PJIs in the NA group (0.63%; p = 0.023). After multivariate analysis, the DA approach was 2.2 times more likely to result in PJI than the NA approach (OR 2.2 (95% confidence interval 1.1 to 3.9); p = 0.006) for the overall study period. CONCLUSION: We found a higher rate of PJI in DA versus NA approaches. Infection prevention protocols such as use of aspirin, dilute povidone-iodine lavage, vancomycin powder, and Gram-negative coverage may have been positively associated with diminished PJI rates observed for all approaches over time. Cite this article: Bone Joint J 2019;101-B(6 Supple B):2-8.

Production of 1,25-dihydroxyvitamin D3 by human T cell lymphotrophic virus-I-transformed lymphocytes.

The human T cell lymphotrophic virus type I (HTLV-I) has recently been identified in a T cell lymphoma associated with hypercalcemia and increased bone turnover. Since increased serum concentrations of 1,25-dihydroxyvitamin D have been reported in this disease, we have examined the capacity of HTLV-I-infected cord blood lymphocytes to metabolize 25-hydroxyvitamin D3. Our results demonstrate that HTLV-I-infected cells have the capacity to metabolize 25-hydroxyvitamin D3 to a substance that co-migrates with 1,25-dihydroxyvitamin D3 by high performance liquid chromatography over a silica column using either 12% isopropanol in hexane or 5% isopropanol in dichloromethane. The metabolite binds to the 1,25-dihydroxyvitamin D3 receptor in rat osteosarcoma cells and stimulates bone resorption in cultures of fetal rat long bones. Mass spectrometric analysis of the metabolite confirmed the presence of 1,25-dihydroxyvitamin D3. Production of 1,25-dihydroxyvitamin D by lymphoma cells may contribute to the pathogenesis of the hypercalcemia seen in patients with HTLV-I-associated T cell lymphomas.

Stepwise recruitment of components of the preinitiation complex by upstream activators in vivo.

Recently, it was found that if either the TATA binding protein or RNA polymerase II holoenzyme is artificially tethered to a promoter, transcription is activated. This finding provided presumptive evidence that upstream activating proteins function by recruiting components of the preinitiation complex (PIC) to the promoter. To date, however, there have been no studies demonstrating that upstream factors actually recruit components of the PIC to the promoter in vivo. Therefore, we have studied the mechanism of action of two disparate transactivating domains. We present a series of in vivo functional assays that demonstrate that each of these proteins targets different components of the PIC for recruitment. We show that, by targeting different components of the PIC for recruitment, these activating domains can cooperate with each other to activate transcription synergistically and that, even within one protein, two different activating subdomains can activate transcription synergistically by cooperating to recruit different components of the PIC. Finally, considering our work together with previous studies, we propose that certain transcription factors both recruit components of the PIC and facilitate steps in transcriptional activation that occur subsequent to recruitment.

Interaction of a common factor with ATF, Sp1, or TATAA promoter elements is required for these sequences to mediate transactivation by the adenoviral oncogene E1a.

The adenovirus protein E1a stimulates transcription of both viral and cellular genes. Unlike most other transcription factors, it induces transactivation through several different promoter elements. The mechanism by which elements of diverse sequence mediate the effect of E1a is the focus of this study. Three E1a-responsive elements (an ATF site, an Sp1 site, and a TATA box containing the sequence TATAA) were studied to determine whether their interaction with a common factor is necessary for transactivation. In transfection assays, each element was used as a competitor against promoter constructs containing the other elements. The elements as competitors had no effect on basal transcription, but each competitor completely inhibited transactivation by E1a. Competitors that were not E1a responsive failed to inhibit transactivation. Therefore, either E1a itself or an E1a-inducible factor interacts with each of the elements to cause transactivation, most likely though an association with each element's specific binding protein.

E2F is required to prevent inappropriate S-phase entry of mammalian cells.

E2F is a family of transcription factors that regulates the cell cycle. It is widely accepted that E2F-mediated transactivation of a set of genes is the critical activity that governs cellular progression through G(1) into S phase. In contrast to this hypothesis, we demonstrate that E2F actually suppresses the onset of S phase in two cell types when the cells are arrested by gamma irradiation. Our findings indicate that in these cells, the critical event triggering progression from G(0)/G(1) arrest into S phase is the release of E2F-mediated transrepression of cell cycle genes, not transactivation by E2F. Furthermore, our data suggest that E2F-mediated transactivation is not necessary for the G(1)/S-phase transition in these cells.

Knee morphometric and alignment measurements with MR imaging in young adults with central cartilage lesions of the patella and trochlea.

PURPOSE: The goal of this study was to assess whether common measurements of patellar and trochlear morphology and patellar alignment are associated with central cartilage lesions of the patella and trochlea using magnetic resonance imaging (MRI). METHODS: The MRI examinations of 58 patients (38 women, 20 men; mean age, 28.59 years [range: 19-35 years]) with central cartilage lesions of the patella and trochlea were retrospectively compared to those obtained in 102 control subjects (57 women, 45 men; mean age, 27.05 years [range: 20-35 years]). Patients had Modified Noyes Classification grade IIA, IIB or III cartilage defects whereas control subjects had normal MRI examination of the knee as determined by two radiologists. Patellar measurements of facet asymmetry, patellar tilt, lateral patellofemoral angle, Insall-Salvati ratio, and patellotrochlear cartilage overlap were performed in patients and control subjects along with trochlear measurements of the trochlear depth and width, and sulcal angle. Multivariate logistic regression adjusted for age and body mass index was used to assess associations. RESULTS: The ratio of the lengths of the medial to lateral facets of the patella (OR=2.7×10-3; P<0.001), angle of the median eminence of the patella (OR=1.05; P=0.040), lateral patellofemoral angle (OR=0.91; P=0.048), Insall-Salvati ratio (OR=364.4; P<0.001) and edema in the superolateral aspect of Hoffa's fat pad (OR=6.52; P<0.001) were significantly associated with central cartilage lesions of the patella and trochlea. CONCLUSION: Central cartilage lesions of the patellofemoral joint are associated with patellar and trochlear morphology, and patellar alignment.

Identification of highly elevated levels of melatonin in bone marrow: its origin and significance.

Bone marrow is an important tissue in generation of immunocompetent and peripheral blood cells. The progenitors of hematopoietic cells in bone marrow exhibit continuous proliferation and differentiation and they are highly vulnerable to acute or chronic oxidative stress. In this investigation, highly elevated levels of the antioxidant melatonin were identified in rat bone marrow using immunocytochemistry, radioimmunoassay, high performance liquid chromatography with electrochemical detection and mass spectrometry. Night-time melatonin concentrations (expressed as pg melatonin/mg protein) in the bone marrow of rats were roughly two orders of magnitude higher than those in peripheral blood. Measurement of the activities of the two enzymes (N-acetyltransferase (NAT) and hydroxyindole-O-methoxyltransferase (HIOMT)) which synthesize melatonin from serotonin showed that bone marrow cells have measurable NAT activity, but they have very low levels of HIOMT activity (at the one time they were measured). From these studies we could not definitively determine whether melatonin was produced in bone marrow cells or elsewhere. To investigate the potential pineal origin of bone marrow melatonin, long-term (8-month) pinealectomized rats were used to ascertain if the pineal gland is the primary source of this antioxidant. The bone marrow of pinealectomized rats, however, still exhibited high levels of melatonin. These results indicate that a major portion of the bone marrow's melatonin is of extrapineal origin. Immunocytochemistry clearly showed a positive melatonin reaction intracellularly in bone marrow cells. A melatonin concentrating mechanism in these cells is suggested by these findings and this may involve a specific melatonin binding protein. Since melatonin is an endogenous free radical scavenger and an immune-enhancing agent, the high levels of melatonin in bone marrow cells may provide on-site protection to reduce oxidative damage to these highly vulnerable hematopoietic cells and may enhance the immune capacity of cells such as lymphocytes.

Molecular heterogeneity of PAF in normal human mixed saliva: quantitative mass spectral analysis after direct derivatization of PAF with pentafluorobenzoic anhydride.

Platelet-activating factor (PAF), a family of phospholipid autacoids with potent pro-inflammatory activities, is present in saliva. The current study has quantitated various species of PAF isolated from normal human mixed saliva. Choline-containing, sn-2 acetylated phospholipids with sn-1 ether- or ester-linked fatty alcohol/acid moieties (alkyl-PAF or acyl-PAF, respectively) were evaluated after direct derivatization with pentafluorobenzoic (PFB) anhydride. Individual species of PFB-derivatized PAF were separated by gas chromatography prior to mass spectral analysis; quantitative estimates of six different species of PAF in saliva were made by comparison to corresponding authentic, synthetic PAF standards. In each saliva sample, all six species of PAF were readily detected by this facile procedure. The predominant PAF was 1-O-hexadecyl-2-acetyl-sn-glycero-3-phosphocholine or 16:0-alkyl-PAF (0.75 +/- 0.09 pmol/ml saliva; mean +/- S.E.; n = 5) which represented only 30.4 +/- 1.5% of the total PAF. Substantial amounts of 18:1- and 18:0-alkyl-PAF and 16:0-acyl-PAF were also identified (0.52 +/- 0.07, 0.35 +/- 0.06, and 0.35 +/- 0.02 pmol/ml saliva, respectively). In summary, mass spectrometric analysis of PAF after direct derivatization with PFB anhydride has revealed that at least six different species of PAF are present in normal human mixed saliva. This structural diversity may represent an important aspect of homeostasis in the healthy oral cavity.

CT-angiography for the detection of a lower gastrointestinal bleeding source.

The evaluation of lower gastrointestinal bleeding (LGIB) often involves the collaborative efforts of the gastroenterologist, radiologist, and surgeon. Efforts to localize the acute LGIB have traditionally involved colonoscopy, technetium-labeled red blood cell (RBC) scintigraphy, angiography, or a combination of these modalities. The sensitivity of each method of diagnosis is limited, with the most common cause of a negative study the spontaneous cessation of hemorrhage. Other technical factors include vasospasm, lack of adequate contrast volume or exposure time, a venous bleeding source, and a large surface bleeding area. We report the use of multidetector computed tomography (MDCT), or CT-angiography (CT-A), in the initial evaluation of LGIB, and speculate on the incorporation of this technique into a diagnostic algorithm to treat LGIB. MDCT may offer a very sensitive means to evaluate the source of acute LGIB, while avoiding some of the morbidity and intense resource use of contrast angiography, and may provide unique morphologic information regarding the type of pathology. Screening with the more rapid and available MDCT, followed by either directed therapeutic angiography or surgical management, may represent a reasonable algorithm for the early evaluation and management of acute LGIB in which an active bleeding source is strongly suspected.

Are there sex differences in neuropsychological functions among patients with schizophrenia?

OBJECTIVE: Studies of sex differences in neuropsychological performance in schizophrenia report inconsistent results, due in part to methodological artifacts. The study presented here was specifically designed to examine sex differences in neuropsychological performance. It was hypothesized that schizophrenic women would exhibit fewer neuropsychological deficits than schizophrenic men and that their performance would be more similar to that of normal women than schizophrenic men's performance would be to that of normal men. METHOD: Thirty-one outpatients with DSM-III-R-defined schizophrenia were systematically sampled from an extensive service network serving a large urban catchment area for seriously mentally ill persons. Twenty-seven normal comparison subjects were matched within sex on the basis of age, parental socioeconomic status, ethnicity, and handedness. An extensive neuropsychological test battery was administered, and multivariate analysis of variance was used to test for the effects of sex and group and sex-by-group interactions. RESULTS: Male patients were significantly impaired across all functions in comparison with normal male subjects and on tests of attention, verbal memory, and executive functions in comparison with female patients. Female patients performed significantly worse than female normal comparison subjects only on tests of attention, executive functions, visual memory, and motor functions. CONCLUSIONS: The findings suggest that women with schizophrenia may be less vulnerable to particular cognitive deficits, especially those involving verbal processing, than schizophrenic men.

Isolation and identification of a phenolic antioxidant from Aloe barbadensis.

A potent antioxidative compound has been isolated from a methanolic extract of Aloe barbadensis Miller using a combination of column and thin-layer chromatography. The antioxidant activity of this substance was similar to that of alpha-tocopherol as assessed in vitro using rat brain homogenates. On the basis of electrospray ionization and electron-impact ionization mass spectra in combination with reversed-phase, high-performance liquid chromatographic behavior, this compound has been identified as 8-C-beta-D-[2-O-(E)-coumaroyl]glucopyranosyl-2-[2-hydroxy]-propyl-7-methoxy-5-methylchromone.