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Diterpenoid natural products serve critical functions in plant development and ecological adaptation and many diterpenoids have economic value as bioproducts. The family of class II diterpene synthases catalyzes the committed reactions in diterpenoid biosynthesis, converting a common geranylgeranyl diphosphate precursor into different bicyclic prenyl diphosphate scaffolds. Enzymatic rearrangement and modification of these precursors generates the diversity of bioactive diterpenoids. We report the crystal structure of Grindelia robusta 7,13-copalyl diphosphate synthase, GrTPS2, at 2.1 Å of resolution. GrTPS2 catalyzes the committed reaction in the biosynthesis of grindelic acid, which represents the signature metabolite in species of gumweed (Grindelia spp., Asteraceae). Grindelic acid has been explored as a potential source for drug leads and biofuel production. The GrTPS2 crystal structure adopts the conserved three-domain fold of class II diterpene synthases featuring a functional active site in the γβ-domain and a vestigial ɑ-domain. Substrate docking into the active site of the GrTPS2 apo protein structure predicted catalytic amino acids. Biochemical characterization of protein variants identified residues with impact on enzyme activity and catalytic specificity. Specifically, mutagenesis of Y457 provided mechanistic insight into the position-specific deprotonation of the intermediary carbocation to form the characteristic 7,13 double bond of 7,13-copalyl diphosphate., Competing Interests: Conflict of interest statement The authors declare no competing interests, (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

The intricate communication between plastids and the nucleus, shaping stress-responsive gene expression, has long intrigued researchers. This study combines genetics, biochemical analysis, cellular biology, and protein modeling to uncover how the plastidial metabolite MEcPP activates the stress-response regulatory hub known as the Rapid Stress Response Element (RSRE). Specifically, we identify the HAT1/TPL/IMPα- 9 suppressor complex, where HAT1 directly binds to RSRE and its activator, CAMTA3, masking RSRE and sequestering the activator. Stress-induced MEcPP disrupts this complex, exposing RSRE and releasing CAMTA3, while enhancing Ca 2+ influx and raising nuclear Ca 2+ levels crucial for CAMTA3 activation and the initiation of RSRE- containing gene transcription. This coordinated breakdown of the suppressor complex and activation of the activator highlights the dual-channel role of MEcPP in plastid-to- nucleus signaling. It further signifies how this metabolite transcends its expected biochemical role, emerging as a crucial initiator of harmonious signaling cascades essential for maintaining cellular homeostasis under stress., Summary: This study uncovers how the stress-induced signaling metabolite MEcPP disrupts the HAT1/TPL/IMPα-9 suppressor complex, liberating the activator CAMTA3 and enabling Ca 2+ influx essential for CAMTA3 activation, thus orchestrating stress responses via repressor degradation and activator induction.

Phytohormone levels are regulated through specialized enzymes, participating not only in their biosynthesis but also in post-signaling processes for signal inactivation and cue depletion. Arabidopsis thaliana (At) carboxylesterase 15 (CXE15) and carboxylesterase 20 (CXE20) have been shown to deplete strigolactones (SLs) that coordinate various growth and developmental processes and function as signaling molecules in the rhizosphere. Here, we elucidate the X-ray crystal structures of AtCXE15 (both apo and SL intermediate bound) and AtCXE20, revealing insights into the mechanisms of SL binding and catabolism. The N-terminal regions of CXE15 and CXE20 exhibit distinct secondary structures, with CXE15 characterized by an alpha helix and CXE20 by an alpha/beta fold. These structural differences play pivotal roles in regulating variable SL hydrolysis rates. Our findings, both in vitro and in planta, indicate that a transition of the N-terminal helix domain of CXE15 between open and closed forms facilitates robust SL hydrolysis. The results not only illuminate the distinctive process of phytohormone breakdown but also uncover a molecular architecture and mode of plasticity within a specific class of carboxylesterases., (© 2024. The Author(s).)

The bone marrow overproduces immature cells in the malignancy known as Acute Lymphoblastic Leukemia (ALL). In the United States, about 6500 occurrences of ALL are diagnosed each year in both children and adults, comprising nearly 25% of pediatric cancer cases. Recently, many computer-assisted diagnosis (CAD) systems have been proposed to aid hematologists in reducing workload, providing correct results, and managing enormous volumes of data. Traditional CAD systems rely on hematologists' expertise, specialized features, and subject knowledge. Utilizing early detection of ALL can aid radiologists and doctors in making medical decisions. In this study, Deep Dilated Residual Convolutional Neural Network (DDRNet) is presented for the classification of blood cell images, focusing on eosinophils, lymphocytes, monocytes, and neutrophils. To tackle challenges like vanishing gradients and enhance feature extraction, the model incorporates Deep Residual Dilated Blocks (DRDB) for faster convergence. Conventional residual blocks are strategically placed between layers to preserve original information and extract general feature maps. Global and Local Feature Enhancement Blocks (GLFEB) balance weak contributions from shallow layers for improved feature normalization. The global feature from the initial convolution layer, when combined with GLFEB-processed features, reinforces classification representations. The Tanh function introduces non-linearity. A Channel and Spatial Attention Block (CSAB) is integrated into the neural network to emphasize or minimize specific feature channels, while fully connected layers transform the data. The use of a sigmoid activation function concentrates on relevant features for multiclass lymphoblastic leukemia classification The model was analyzed with Kaggle dataset (16,249 images) categorized into four classes, with a training and testing ratio of 80:20. Experimental results showed that DRDB, GLFEB and CSAB blocks' feature discrimination ability boosted the DDRNet model F1 score to 0.96 with minimal computational complexity and optimum classification accuracy of 99.86% and 91.98% for training and testing data. The DDRNet model stands out from existing methods due to its high testing accuracy of 91.98%, F1 score of 0.96, minimal computational complexity, and enhanced feature discrimination ability. The strategic combination of these blocks (DRDB, GLFEB, and CSAB) are designed to address specific challenges in the classification process, leading to improved discrimination of features crucial for accurate multi-class blood cell image identification. Their effective integration within the model contributes to the superior performance of DDRNet., (© 2024. The Author(s).)

Objective  To study the etiological and anatomical factors in pathophysiology of invasive fungal rhinosinusitis affecting the skull base. Design  Retrospective clinical study over 5 years. Setting  Single-center tertiary referral hospital. Materials and Methods  All cases of invasive fungal rhinosinusitis with clinicoradiological and/or operative evidence of anterior and central skull base, orbit, and orbital apex involvement with or without intracranial disease were included in the study. Patients with a sinonasal-palatal disease without the involvement of the skull base or orbit were excluded from the study. In addition, we assessed the risk factors such as coronavirus disease 2019 (COVID-19) infection, diabetes mellitus (DM), and other immunocompromised conditions. Results  There were 79 patients, of which 65.8% had skull base rhino-oribitocerebral mucormycosis (ROCM), and 34.2% had Aspergillus infection. The mean duration from onset of the symptom to presentation of ROCM was 36.75 ± 20.97 days, while for the Aspergillus group was 21 weeks. The majority of patients (66%) with ROCM presented after 30 days of symptom onset. Among ROCM patients, 88.7% had a history of COVID-19 infection, and 96% had DM. In 40.8% of patients with Aspergillus infection, the tissue diagnosis was unavailable, and galactomannan assay and clinicoradiological assessment were used for diagnosis. The most common area of the skull base involved was the pterygopalatine fossa (88.5%), followed by the infratemporal fossa (73.1%). The most common neurovascular structure (75%) involved was the pterygopalatine ganglion and the infraorbital nerve. Conclusion  With the increasing incidence of invasive fungal infections worldwide, particularly after the COVID-19 pandemic, it is crucial to understand the evolving nature of this disease. ROCM, documented in the literature to cause fulminant disease, became a chronic illness, possibly due to the improvement of the patient's immunity during the disease course., Competing Interests: Conflict of Interest None declared., (Thieme. All rights reserved.)

In this work, we present the generation of two distinct types of soliton pulses using a Bismuth Selenide (Bi 2 Se 3 ) saturable absorber (SA) synthesized in our laboratory. The soliton pulses were generated in two different laser cavity configurations, resulting in two types of solitons: a soliton pulse with Kelly sidebands and a bunched soliton pulse with peak-dip sidebands. Both solitons operated at the fundamental repetition rate-23.3 MHz (for the soliton with Kelly sidebands) and 13 MHz (for the bunched soliton with peak-dip sidebands). We observed that the accumulation of nonlinear phase shift from the added single mode fiber (SMF) split the single soliton pulse into 44 pulses in a bunched oscillation envelope. At the same time, peak-dip sidebands were imposed on the bunched soliton spectrum due to constructive and destructive interferences between soliton pulse and dispersive waves. The measured pulse width for both solitons were 0.63 ps (for the soliton with Kelly sidebands) and 1.52 ps (for the bunched soliton with peak-dip sidebands), respectively. Our results demonstrate the potential of Bi 2 Se 3 SAs in generating different types of soliton pulses, which could have potential applications in various areas of optical communication and spectroscopy.

Idiopathic pulmonary fibrosis (IPF) is a chronic lung disease with a very poor prognosis as it has a 2.5 to 5 years mean survival after proper diagnosis. Even nintedanib and pirfenidone cannot halt the progression, though they slow the progression of IPF. Hence, there is a need to understand the novel pathophysiology. Phospholipase A2 (PLA2) could be the ideal candidate to study in IPF, as they have a role in both inflammation and fibrosis. In the present study, we have shown the expression profile of various secretory Phospholipase A2 (PLA2) isoforms by analyzing publicly available transcriptome data of single cells from the lungs of healthy individuals and IPF patients. Among 11 members of sPLA2, PLA2G2A is found to be increased in the fibroblasts and mesothelial cells while PLA2G5 is found to be increased in the fibroblasts of IPF patients. We identified a subset of fibroblasts expressing high PLA2G2A with moderate expression of PLA2G5 and which are specific to IPF only; we named it as PLA2G2A+ IPF fibroblast. Pathway analysis revealed that these PLA2G2A+ IPF fibroblast have upregulation of both inflammatory and fibrosis-related pathways like the TGF-β signaling pathway, IL-17 signaling, the arachidonic acid metabolism pathway and ECM-receptor interaction. In addition to this, we found elevated levels of sPLA2-IIA in plasma samples of IPF patients in our cohort. PLA2G3, PLA2G10 and PLA2G12B are found in to be increased in certain epithelial cells of IPF patients. Thus, these findings indicate that these five isoforms have a disease-dominant role along with innate immune roles as these isoforms are found predominantly in structural cells of IPF patients. Further, we have targeted sPLA2 in mice model of bleomycin-induced lung fibrosis by pBPB, a known sPLA2 inhibitor. pBPB treatment attenuated lung fibrosis induced by bleomycin along with a reduction in TGF-β and deposition of extracellular matrix in lung. Thus, these findings indicate that these sPLA2 isoforms especially PLA2G2A may serve as a therapeutic target in lung fibrosis.

Microbottle resonators (MBR) are bottle-like structures fabricated by varying the radius of an optical fiber. MBRs can support whispering gallery modes (WGM) by the total internal reflection of the light coupled into the MBRs. MBRs have a significant advantage in sensing and other advanced optical applications due to their light confinement abilities in a relatively small mode volume and having high Q factors. This review starts with an introduction to MBRs' optical properties, coupling methods, and sensing mechanisms. The sensing principle and sensing parameters of MBRs are discussed here as well. Then, practical MBRs fabrication methods and sensing applications are presented.

We report the fabrication of an erbium-doped fiber-based saturable absorber (SA) of niobium aluminium carbide (Nb 2 AlC) nanomaterial that can generate a dissipative soliton mode-locked pulse. Stable mode-locked pulses operating at 1530 nm with repetition rates of 1 MHz and pulse widths of 6.375 ps were produced using polyvinyl alcohol (PVA) and the Nb2AlC nanomaterial. A peak pulse energy of 7.43 nJ was measured at 175.87 mW pump power. In addition to providing some useful design suggestions for manufacturing SAs based on MAX phase materials, this work shows the MAX phase materials' immense potential for making ultra-short laser pulses.

Nationwide perspectives on cannabis have changed dramatically over recent decades. Although cannabis remains illegal at the federal level, medical cannabis (MC) is now legal in most states, and research has continued to show its effectiveness in a variety of medical conditions. However, both perception and acceptance of MC by the general public are evolving and remain poorly understood. Treating patients effectively with these novel therapeutics requires an understanding of the complex interplay of social and legal factors that could affect patient use. This cross-sectional survey study of more than 2500 patients sought to assess current patient perspectives on MC and to investigate factors related to its use that may represent barriers to broader patient use. Most respondents would consider using MC for chronic pain or other medical conditions. Most respondents were aware of the legal status of MC in their state, and 9 of 10 respondents believed that MC should be legal throughout the United States. General public knowledge of the utility of MC is an area needing improvement because older patients were significantly less likely to believe that MC is safe to use or that MC is safer than prescription opioids. As has been reported in previous literature, social stigma and cost appear to remain barriers for patient use of MC. Our findings provide further insight into current patient perspectives on MC, aiding both medical providers and researchers as we continue to provide access to and research MC. [ Orthopedics . 2022;45(6):e309-e314.].

Geopolymer mortar is the best solution as an alternative to cement mortar in civil engineering. This paper deals with the effect of geopolymer mortar on the strength and microstructural properties under ambient curing conditions. In this research, geopolymer mortars were prepared with fly ash and steel slag (in the ratio 1:2.0, 1:2.5 and 1:3.0) as precursors with NaOH and Na 2 SiO 3 as activator solution solutions (in the ratios of 0.5, 0.75 and 1.0) with concentrations of NaOH as 8 M, 10 M, 12 M and 14 M to study the compressive strength behaviour. From the experimental results, it was observed that the geopolymer mortar mix with the ratio of fly ash and steel slag 1:2.5, 12 M NaOH solution and the ratio of NaOH and Na 2 SiO 3 0.5 exhibits the maximum compressive strength results in the range of 55 MPa to 60 MPa. From the optimized results, ferrocement panels of size 1000 mm × 1000 mm × 50 mm were developed to study the flexural behaviour. The experimental results of the flexural strength were compared with the analytical results developed through ABAQUS software. It was observed that the Trough-shaped geopolymer ferrocement panel exhibits 56% higher value in its ultimate strength than the analytical work. In addition to the strength properties, microstructural analysis was carried out in the form of SEM, EDAX and XRD from the tested samples.

High-strength concrete is designed for a self-weight reduction structure and exhibits higher resistance to compressive loads. This paper proposes a novel technique to enhance concrete's properties using Magnetic Field Treated Water (MFTW), describing the results of experimental studies to apprehend the fresh, hardened and microstructural behavior of concrete prepared with Magnetic Water (MW) using a permanent magnet with a field intensity of 0.9 Tesla. The novel scheme focuses on utilizing MW as a water-reducing agent instead of SP to improve the workability of fresh concrete with a 0.38 w/c ratio for achieving M40 grade concrete. Results show a 12% improvement in compressive strength and an 8.9% improvement in split tensile strength compared to normal water (NW) with 1% SP. At 30% cement volume reduction, Magnetic Water Concrete (MWC) performs better than Normal Water Concrete (NWC). Microstructure examination shows that a smaller Calcium Hydrate (CH) crystal is formed with MW and its mineral composition is observed through Energy Dispersive X-ray Analysis (EDAX).

The characteristics of a concrete mix are purely dependent on the hydration of cement that is carried forward by using the water quality used in the mix. Several researchers have focused on incorporating pozzolanic or nanomaterials to improve the hydration mechanisms and impart high strength to concrete. A new technology has been introduced to improve the properties of concrete by magnetic-field-treated water (MFTW). Due to magnetization, water particles become charged and the molecules inside the water cluster decrease from 13 to 5 or 6, which eventually decreases the hardness of water, thus improving the strength of concrete when compared to the use of normal water (NW). In advanced construction techniques and practices, the application of Magnetic Water (MW) plays an important role in boosting physicochemical properties. This research work focused on evaluating the standards of water quality through physiochemical analysis, such as Electrical Conductivity (EC), Viscosity, pH, and Total Dissolved Solids (TDS) with the MW at different exposure periods (60 min (MW60), 45 min (MW45), 30 min (MW30), 15 min (MW15), and instant exposure (MWI)). Experiments were carried out to evaluate the fresh, hardened, and microstructural behavior of concrete made with magnetic water (MW) using a permanent magnet of PERMAG (N407) under a field intensity of 0.9 Tesla. In addition, optical properties such as X-ray Diffraction (XRD) and Ultraviolet (UV) absorption were considered for the MW60 mix to ensure water magnetization. Characterization methods such as Fourier Transform Infrared Spectroscopy (FT-IR), Thermogravimetric Analysis (TGA), and Scanning Electron Microscopy (SEM) were employed for NWC and MWC to quantify the hydrated products. From the results, it was observed that the magnetic effect on water characteristics showed significant improvement in the concrete properties with the increase in exposure duration. There were increments of 25.6% and 24.1% in workability and compressive strength, respectively, for the MW60 mix compared to normal water concrete (NWC).

This research tests energy optimised furnace (EOF) steel slag as substitution for natural coarse aggregate in concrete. Steel slag's usefulness as a substitute for natural coarse aggregate in concrete is the primary goal of this research. According to IS:2386-1963, the characterization of EOF steel slag, as coarse, is done by examining the shape and size of a particle, mechanical properties, physical properties, soundness, and alkali-aggregate reactivity. Tests for detection of staining material in steel slag and hardness of inter-facial transition zone in hardened cement paste were also carried out. The chemical analysis of the steel slag reveals the stability of oxides present in the steel slag. Microstructural characterization by SEM (scanning electron microscope) analysis of steel slag aggregate was also employed to support the characterization and XRD analysis, and it was found that the EOF steel slag is crystalline. The digital image processing technique (DIP) is adopted to study the shape indices, circularity, sphericity, shape factor, and roundness of natural and EOF steel slag aggregate. According to the characterization and strength investigation, steel slag aggregate outperforms natural coarse aggregate.

Background: Telemedicine facilitates patient care in various fields including antenatal care. Its application and usefulness need objectification and can be a guide to using this service in the care of pregnant women., Material and Methods: This was a prospective observational study conducted from May 2020 to December 2020. Following the telemedicine practice guideline of the country, 3,360 teleconsultations were sought by 862 antenatal patients. The duration of each call, an indication of referral and pregnancy risk stratification were noted. Further management was classified into three categories depending upon the need for an immediate hospital visit, no hospital visit or scheduled visit after at least 48 h after the first contact., Results: The antenatal cases were referred for either maternal, foetal or both indications in 24.7, 54.8 and 20.5% of the cases, respectively. Women were classified as low risk (61.6%), high risk (35.7%) and severe risk (2.7%). In 1.4% of the patients, history and review of the records could not be done through telemedicine. The average time spent was 16.6 min for the first contact and 3.1 min for subsequent contacts. Further management was done with immediate visits in 385 (45.3%), scheduled hospital visits in 292 (34.3%) women and no tertiary care hospital visit in 173 (20.4%)., Discussion: Women (20.4%) not called to the maternal-foetal medicine department of the institute were managed along with the treating obstetrician and no difference in pregnancy outcome was noted., Conclusion: Antenatal care can be provided following triage over teleconsultation and 1.4% of the women may not be able to use telehealth., Competing Interests: There are no conflicts of interest., (Copyright: © 2022 Journal of Family Medicine and Primary Care.)

A 24 kDa leucine-rich protein from ion exchange fractions of Solanum trilobatum , which has anti-bacterial activity against both the Gram-negative Vibrio cholerae and Gram-positive Staphylococcus aureus bacteria has been purified. In this study, mass spectrometry analysis identified the leucine richness and found a luminal binding protein (LBP). Circular dichroism suggests that the protein was predominantly composed of α- helical contents of its secondary structure. Scanning electron microscopy visualized the characteristics and morphological and structural changes in LBP-treated bacterium. Further in vitro studies confirmed that mannose-, trehalose- and raffinose-treated LBP completely inhibited the hemagglutination ability towards rat red blood cells. Altogether, these studies suggest that LBP could bind to sugar moieties which are abundantly distributed on bacterial surface which are essential for maintaining the structural integrity of bacteria. Considering that Solanum triolbatum is a well-known medicinal and edible plant, in order to shed light on its ancient usage in this work, an efficient anti-microbial protein was isolated, characterized and its in vitro functional study against human pathogenic bacteria was evaluated.

The ERK1/2 (also known as MAPK3 and MAPK1, respectively) signaling pathway is critical in organismal development and tissue morphogenesis. Deregulation of this pathway leads to congenital abnormalities with severe developmental dysmorphisms. The core ERK1/2 cascade relies on scaffold proteins, such as Shoc2 to guide and fine-tune its signals. Mutations in SHOC2 lead to the development of the pathology termed Noonan-like Syndrome with Loose Anagen Hair (NSLAH). However, the mechanisms underlying the functions of Shoc2 and its contributions to disease progression remain unclear. Here, we show that ERK1/2 pathway activation triggers the interaction of Shoc2 with the ubiquitin-specific protease USP7. We reveal that, in the Shoc2 module, USP7 functions as a molecular 'switch' that controls the E3 ligase HUWE1 and the HUWE1-induced regulatory feedback loop. We also demonstrate that disruption of Shoc2-USP7 binding leads to aberrant activation of the Shoc2-ERK1/2 axis. Importantly, our studies reveal a possible role for USP7 in the pathogenic mechanisms underlying NSLAH, thereby extending our understanding of how ubiquitin-specific proteases regulate intracellular signaling., Competing Interests: Competing interests The authors declare no competing or financial interests., (© 2021. Published by The Company of Biologists Ltd.)

Background: Identification of implant model from primary knee arthroplasty in pre-op planning of revision surgery is a challenging task with added delay. The direct impact of this inability to identify the implants in time leads to the increase in complexity in surgery. Deep learning in the medical field for diagnosis has shown promising results in getting better with every iteration. This study aims to find an optimal solution for the problem of identification of make and model of knee arthroplasty prosthesis using automated deep learning models., Methods: Deep learning algorithms were used to classify knee arthroplasty implant models. The training, validation and test comprised of 1078 radiographs with a total of 6 knee arthroplasty implant models with anterior-posterior (AP) and lateral views. The performance of the model was calculated using accuracy, sensitivity, and area under the receiver-operating characteristic curve (AUC), which were compared against multiple models trained for comparative in-depth analysis with saliency maps for visualization., Results: After training for a total of 30 epochs on all 6 models, the model performing the best obtained an accuracy of 96.38%, the sensitivity of 97.2% and AUC of 0.985 on an external testing dataset consisting of 162 radiographs. The best performing model correctly and uniquely identified the implants which could be visualized using saliency maps., Conclusion: Deep learning models can be used to differentiate between 6 knee arthroplasty implant models. Saliency maps give us a better understanding of which regions the model is focusing on while predicting the results., Competing Interests: Conflict of interestThe authors declare no conflict of interest., (© Indian Orthopaedics Association 2021.)

The stringent response, regulated by the bifunctional (p)ppGpp synthetase/hydrolase Rel in mycobacteria, is critical for long-term survival of the drug-tolerant dormant state of Mycobacterium tuberculosis. During amino acid starvation, MtRel senses a drop in amino acid concentration and synthesizes the messengers pppGpp and ppGpp, collectively called (p)ppGpp. Here, we investigate the role of the regulatory 'Aspartokinase, Chorismate mutase and TyrA' (ACT) domain in MtRel. Using NMR spectroscopy approaches, we report the high-resolution structure of dimeric MtRel ACT which selectively binds to valine out of all other branched-chain amino acids tested. A set of MtRel ACT mutants were generated to identify the residues required for maintaining the head-to-tail dimer. Through NMR titrations, we determined the crucial residues for binding of valine and show structural rearrangement of the MtRel ACT dimer in the presence of valine. This study suggests the direct involvement of amino acids in (p)ppGpp accumulation mediated by MtRel independent to interactions with stalled ribosomes. Database Structural data are available in the PDB database under the accession number 6LXG., (© 2020 Federation of European Biochemical Societies.)

Cryptochromes (CRYs) are evolutionarily conserved photoreceptors that mediate various light-induced responses in bacteria, plants, and animals. Plant cryptochromes govern a variety of critical growth and developmental processes including seed germination, flowering time and entrainment of the circadian clock. CRY's photocycle involves reduction of their flavin adenine dinucleotide (FAD)-bound chromophore, which is completely oxidized in the dark and semi to fully reduced in the light signaling-active state. Despite the progress in characterizing cryptochromes, important aspects of their photochemistry, regulation, and light-induced structural changes remain to be addressed. In this study, we determine the crystal structure of the photosensory domain of Arabidopsis CRY2 in a tetrameric active state. Systematic structure-based analyses of photo-activated and inactive plant CRYs elucidate distinct structural elements and critical residues that dynamically partake in photo-induced oligomerization. Our study offers an updated model of CRYs photoactivation mechanism as well as the mode of its regulation by interacting proteins.

Background: The occurrence of lung adenocarcinoma metastasizing to the pancreas is overall rare and can histologically imitate primary pancreatic ductal carcinoma (PDAC)., Case Report: This is a case report of a 70-year-old female with a history of surgically resected right lung adenocarcinoma presenting for routine follow up without symptoms. CT scans revealed a pancreatic cystic mass with ductal dilatation that was sampled via endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) and thought to be a primary pancreatic mucinous neoplasm with high grade dysplasia suspicious for carcinoma based on smear cytology. On repeat EUS-FNA and biopsy (FNB) with additional immunohistochemical testing for lung adenocarcinoma markers thyroid transcription factor (TTF1) and Napsin A and molecular testing, the lesion was identified as a metastasis of lung adenocarcinoma with an epidermal growth factor receptor (EGFR L858R) mutation; subsequently, the patient underwent targeted therapy that yielded an almost complete response., Conclusion: To the best of our knowledge, this is the first documented case in English literature of a lung adenocarcinoma metastasis to the pancreas mimicking a pancreatic primary neoplasm and highlights the potential pitfalls of EUS-FNA for the diagnosis of certain metastases to the pancreas., (Copyright© 2020, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

Sensor devices in wireless sensor networks are vulnerable to faults during their operation in unmonitored and hazardous environments. Though various methods have been proposed by researchers to detect sensor faults, only very few research studies have reported on capturing the dynamics of the inherent states in sensor data during fault occurrence. The continuous density hidden Markov model (CDHMM) is proposed in this research to determine the dynamics of the state transitions due to fault occurrence, while neural networks are utilized to classify the faults based on the state transition probability density generated by the CDHMM. Therefore, this paper focuses on the fault detection and classification using the hybridization of CDHMM and various neural networks (NNs), namely the learning vector quantization, probabilistic neural network, adaptive probabilistic neural network, and radial basis function. The hybrid models of each NN are used for the classification of sensor faults, namely bias, drift, random, and spike. The proposed methods are evaluated using four performance metrics which includes detection accuracy, false positive rate, F1-score, and the Matthews correlation coefficient. The simulation results show that the learning vector quantization NN classifier outperforms the detection accuracy rate when compared to the other classifiers. In addition, an ensemble NN framework based on the hybrid CDHMM classifier is built with majority voting scheme for decision making and classification. The results of the hybrid CDHMM ensemble classifiers clearly indicates the efficacy of the proposed scheme in capturing the dynamics of change of statesm which is the vital aspect in determining rapidly-evolving instant faults that occur in wireless sensor networks.

Purpose: The rapid emergence of multidrug-resistant (MDR) bacteria and the lack of new therapies to eliminate them poses a major threat to global health. With the alarming rise in antimicrobial resistance (AMR), focus has now shifted to the use of the polymyxin class of antibiotics as the last line of defense for treatment of Gram-negative infections. Unfortunately, the growing resistance of bacteria against polymyxins is threatening the treatment of MDR infections, necessitating the need for novel strategies. The objective of this study was to determine if combination of polymyxin (polymyxin B or colistin) with a nonantibiotic small molecule AR-12, a celecoxib derivative that is devoid of cyclooxygenase 2 (COX-2) inhibitory activities, can be an effective strategy against polymyxin-resistant MDR bacteria. Methods: Growth inhibition studies, time-kill assays and permeability assays were conducted to investigate the effect of AR-12 on the antibacterial activity of polymyxins. Results: Growth studies were performed on a panel of polymyxin-resistant MDR strains using the combination of AR-12 with either colistin or polymyxin B. The combination treatment had no effect on strains that have inherent polymyxin resistance; however, AR-12 was effective in lowering the minimal inhibitory concentration (MIC) of polymyxins by 4-60-fold in several strains that had acquired polymyxin resistance. Time-kill assays using the combination of AR-12 and colistin with select MDR strains suggest rapid killing and bactericidal activity, while the permeability assays using fluorescently labeled dansylated polymyxin and 1-N-phenylnaphthylamine (NPN) in these MDR strains suggest that AR-12 can potentiate the antibacterial activity of polymyxins by possibly altering the bacterial outer membrane via modification of lipopolysaccharide and thereby improving the uptake of polymyxins. Conclusion: Our studies indicate that the combination of AR-12 and polymyxin is effective in targeting select Gram-negative bacteria that have acquired polymyxin resistance. Further understanding of the mechanism of action of AR-12 will provide new avenues for developing narrow-spectrum antibacterials to target select Gram-negative MDR bacteria. Importantly, our studies show that the use of nonantibiotic small molecules in combination with polymyxins is an attractive strategy to counter the growing resistance of bacteria to polymyxins., Competing Interests: Dr. Malathy Krishnamurthy was supported by the National Research Council (NRC) Research Associateship Award at USAMRIID. Mr. Evan M Falcinelli was supported by Science and Engineering Apprentice Program (SEAP) at USAMRIID. Mr. Reuel A Sandy, Ms. Jennifer N Dootz and Dr. Tiffany M Mott were supported by the Oak Ridge Institute for Science and Education (ORISE) Fellowship. The authors report no other conflicts of interest in this work.

Effective vaccine design relies on accurate knowledge of protection against a pathogen, so as to be able to induce relevant and effective protective responses against it. An ideal Human Immunodeficiency virus (HIV) vaccine should induce humoral as well as cellular immune responses to prevent initial infection of host cells or limit early events of viral dissemination. A Phase I HIV-1 prophylactic vaccine trial sponsored by the International AIDS Vaccine Initiative (IAVI) was conducted in India in 2009.The trial tested a HIV-1 subtype C vaccine in a prime-boost regimen, comprising of a DNA prime (ADVAX) and Modified Vaccine Ankara (MVA) (TBC-M4) boost. The trial reported that the vaccine regimen was safe, well tolerated, and resulted in enhancement of HIV-specific immune responses. However, preliminary immunological studies were limited to vaccine-induced IFN-γ responses against the Env and Gag peptides. The present study is a retrospective study to characterize in detail the nature of the vaccine-induced cell mediated immune responses among volunteers, using Peripheral Blood Mononuclear Cells (PBMC) that were archived during the trial. ELISpot was used to measure IFN-γ responses and polyfunctional T cells were analyzed by intracellular multicolor flow cytometry. It was observed that DNA priming and MVA boosting induced Env and Gag specific bi-functional and multi-functional CD4+ and CD8+ T cells expressing IFN-γ, TNF-α and IL-2. The heterologous prime-boost regimen appeared to be slightly superior to the homologous prime-boost regimen in inducing favorable cell mediated immune responses. These results suggest that an in-depth analysis of vaccine-induced cellular immune response can aid in the identification of correlates of an effective immunogenic response, and inform future design of HIV vaccines., Competing Interests: The authors have declared that no competing interests exist.

A fit and healthy 26-year-old woman presented to the general surgical team with epigastric pain and weight loss of 2 stones over 6 months. She has also a positive family history of ulcerative colitis. As her oesophagogastroduodenoscopy and colonoscopy were normal, a contrasted CT was requested, and it detected an inflammatory mass with fat streaking around her transverse colon. An intrauterine contraceptive device (IUCD) was noted. In light of the CT findings, she underwent a diagnostic laparoscopy. As the inflammatory mass was not separable from the transverse colon, a segmental transverse colectomy was proceeded. The histology revealed multiple actinomycosis abscesses in the mesentery. Subsequently, we learnt that her IUCD had been in situ for the last 7 years, and the source of actinomycosis abscesses is likely from her IUCD. The patient was recommended to have the coil removed and commenced on a 6 months course of amoxicillin., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2019. No commercial re-use. See rights and permissions. Published by BMJ.)

Competing Interests: There are no conflicts of interest.

RNA viruses are characterized by a high mutation rate, a buffer against environmental change. Nevertheless, the means by which random mutation improves viral fitness is not well characterized. Here we report the X-ray crystal structure of the receptor-binding domain (RBD) of the human coronavirus, HCoV-229E, in complex with the ectodomain of its receptor, aminopeptidase N (APN). Three extended loops are solely responsible for receptor binding and the evolution of HCoV-229E and its close relatives is accompanied by changing loop-receptor interactions. Phylogenetic analysis shows that the natural HCoV-229E receptor-binding loop variation observed defines six RBD classes whose viruses have successively replaced each other in the human population over the past 50 years. These RBD classes differ in their affinity for APN and their ability to bind an HCoV-229E neutralizing antibody. Together, our results provide a model for alphacoronavirus adaptation and evolution based on the use of extended loops for receptor binding.

Protein O-glucosyltransferase 1/Rumi-mediated glucosylation of Notch epidermal growth factor-like (EGF-like) domains plays an important role in Notch signaling. Protein O-glucosyltransferase 1 shows specificity for folded EGF-like domains, it can only glycosylate serine residues in the C 1 XSXPC 2 motif, and it possesses an uncommon dual donor substrate specificity. Using several EGF-like domains and donor substrate analogs, we have determined the structures of human Protein O-glucosyltransferase 1 substrate/product complexes that provide mechanistic insight into the basis for these properties. Notably, we show that Protein O-glucosyltransferase 1's requirement for folded EGF-like domains also leads to its serine specificity and that two distinct local conformational states are likely responsible for its ability to transfer both glucose and xylose. We also show that Protein O-glucosyltransferase 1 possesses the potential to xylosylate a much broader range of EGF-like domain substrates than was previously thought. Finally, we show that Protein O-glucosyltransferase 1 has co-evolved with EGF-like domains of the type found in Notch.POGLUT1 is a protein-O-glucosyltransferase that transfers glucose and xylose to the EGF-like domains of Notch and other signaling receptors. Here the authors report the structure of human POGLUT1 in complexes with 3 different EGF-like domains and donor substrates and shed light on the enzyme's substrate specificity and catalytic mechanism.

Background: The emergence and prevalence of multidrug resistant (MDR) pathogenic bacteria poses a serious threat to human and animal health globally. Nosocomial infections and common ailments such as pneumonia, wound, urinary tract, and bloodstream infections are becoming more challenging to treat due to the rapid spread of MDR pathogenic bacteria. According to recent reports by the World Health Organization (WHO) and Centers for Disease Control and Prevention (CDC), there is an unprecedented increase in the occurrence of MDR infections worldwide. The rise in these infections has generated an economic strain worldwide, prompting the WHO to endorse a global action plan to improve awareness and understanding of antimicrobial resistance. This health crisis necessitates an immediate action to target the underlying mechanisms of drug resistance in bacteria., Research: The advent of new bacterial genome engineering and synthetic biology (SB) tools is providing promising diagnostic and treatment plans to monitor and treat widespread recalcitrant bacterial infections. Key advances in genetic engineering approaches can successfully aid in targeting and editing pathogenic bacterial genomes for understanding and mitigating drug resistance mechanisms. In this review, we discuss the application of specific genome engineering and SB methods such as recombineering, clustered regularly interspaced short palindromic repeats (CRISPR), and bacterial cell-cell signaling mechanisms for pathogen targeting. The utility of these tools in developing antibacterial strategies such as novel antibiotic production, phage therapy, diagnostics and vaccine production to name a few, are also highlighted., Conclusions: The prevalent use of antibiotics and the spread of MDR bacteria raise the prospect of a post-antibiotic era, which underscores the need for developing novel therapeutics to target MDR pathogens. The development of enabling SB technologies offers promising solutions to deliver safe and effective antibacterial therapies.

Background: The Cotard delusion (CD) is one of a variety of narrowly defined monothematic delusions characterized by nihilistic beliefs about the body's existence or life itself. The presence of CD within the context of schizophrenia is rare (<1%), and remains understudied., Case: 'Mr. C' is a 58-year-old veteran with a prior diagnosis of schizophrenia, who presented with CD in the context of significant depression, suicidal ideation, violence, and self-harm behavior. He perseverated in his belief that he was physically dead and possessed by demons for several weeks. This delusion was reinforced by his religious belief that life was an attribute of God, and by inference, he as a human, was dead. His condition gradually improved over the course of treatment with Divalproex and quetiapine with discussions about the rationale for his belief. Upon discharge, Mr. C. demonstrated awareness of his fixation on death and an ability to redirect himself., Discussion: This case highlights the need to better understand the co-occurrence of CD in schizophrenia, their differentiation, the increased risk of violence and self-harm behavior in this presentation, and how specific events and religious factors can influence delusional themes of CD. Pharmacotherapy and aspects of cognitive-behavioral therapy may be effective in ameliorating these symptoms in CD.

Obesity is a growing epidemic with limited effective treatments. The neurotrophic factor glial cell line-derived neurotrophic factor (GDNF) was recently shown to enhance β-cell mass and improve glucose control in rodents. Its role in obesity is, however, not well characterized. In this study, we investigated the ability of GDNF to protect against high-fat diet (HFD)-induced obesity. GDNF transgenic (Tg) mice that overexpress GDNF under the control of the glial fibrillary acidic protein promoter and wild-type (WT) littermates were maintained on a HFD or regular rodent diet for 11 wk, and weight gain, energy expenditure, and insulin sensitivity were monitored. Differentiated mouse brown adipocytes and 3T3-L1 white adipocytes were used to study the effects of GDNF in vitro. Tg mice resisted the HFD-induced weight gain, insulin resistance, dyslipidemia, hyperleptinemia, and hepatic steatosis seen in WT mice despite similar food intake and activity levels. They exhibited significantly (P<0.001) higher energy expenditure than WT mice and increased expression in skeletal muscle and brown adipose tissue of peroxisome proliferator activated receptor-α and β1- and β3-adrenergic receptor genes, which are associated with increased lipolysis and enhanced lipid β-oxidation. In vitro, GDNF enhanced β-adrenergic-mediated cAMP release in brown adipocytes and suppressed lipid accumulation in differentiated 3T3L-1 cells through a p38MAPK signaling pathway. Our studies demonstrate a novel role for GDNF in the regulation of high-fat diet-induced obesity through increased energy expenditure. They show that GDNF and its receptor agonists may be potential targets for the treatment or prevention of obesity.

Background: Fluoroscopic guided percutaneous interventional spine procedures are increasingly performed in recent years as they have been shown to be target specific and enhance patient safety. However, ionizing radiation has been associated with stochastic effects such as cancer and genetic defects as well as deterministic effects such as cataracts, erythema, epilation, and even death. These are dose related, and hence, measures should be taken to minimize radiation exposure to patients and health care personnel to reduce these adverse effects., Objective: A risk reduction project was completed with the goal of reducing effective doses to the staff and patients in a university-based spinal interventional practice. Effective dose reduction to the staff and patients was hypothesized to occur with technique and equipment changes in the procedure suite. The goal of this study was to quantify effective dose rates to staff before and after interventions., Study Design: Retrospective study comparing descriptive data of effective dose to the health care staff before and after implementation of a combination of technique and equipment changes., Methods: Technique changes from pre to post intervention period included continuous needle advancement under continuous fluoroscopic controlled by the interventional physician to intermittent needle advancement under pulsed fluoroscopic controlled by the radiology technician. Equipment changes included circumferential lead drape skirt around the procedure table and use of mobile transparent lead barriers on both sides of the procedure table.Effective dose exposure measured in Millirem (mrem) from the radiation dosimetry badges for pre-intervention (February 2009 through June 2009) and post-intervention (November 2009 through March 2010) periods were examined through monthly radiation dosimetry reports for the fluoroscopy suite staff., Results: A total of 685 interventional procedures were performed in the pre-intervention period and 385 in the post-intervention period. The median cumulative mrem (interquartile range) for all staff combined in the pre-intervention period was 71 (28,75) and post-intervention period was 1 (0,3). The median mrem per procedure was significantly higher in the pre-intervention group 0.46 (0.36, 0.54) compared to post-intervention 0.01 (0.0.03); P < 0.01. The percentage reduction in overall effective dose per procedure to all staff was 97.3%., Limitations: Observational study, multiple radiation reduction interventions confound the individual effects of each intervention's effective dose, Conclusions: Spinal injection technique and equipment changes in the procedure suite significantly reduced the rate of effective dose to the clinical staff.

Compared to transcriptional activation, other mechanisms of gene regulation have not been widely exploited for the control of transgenes. One barrier to the general use and application of alternative splicing is that splicing-regulated transgenes have not been shown to be reliably and simply designed. Here, we demonstrate that a cassette bearing a suicide exon can be inserted into a variety of open reading frames (ORFs), generating transgenes whose expression is activated by exon skipping in response to a specific protein inducer. The surprisingly minimal sequence requirements for the maintenance of splicing fidelity and regulation indicate that this splicing cassette can be used to regulate any ORF containing one of the amino acids Glu, Gln or Lys. Furthermore, a single copy of the splicing cassette was optimized by rational design to confer robust gene activation with no background expression in plants. Thus, conditional splicing has the potential to be generally useful for transgene regulation.

Pseudomonas aeruginosa produces several phenazines including the recently described 5-methyl-phenazine-1-carboxylic acid (5MPCA), which exhibits a novel antibiotic activity towards pathogenic fungi such as Candida albicans. Here we characterize the unique antifungal mechanisms of 5MPCA using its analogue phenazine methosulphate (PMS). Like 5MPCA, PMS induced fungal red pigmentation and killing. Mass spectrometry analyses demonstrated that PMS can be covalently modified by amino acids, a process that yields red derivatives. Furthermore, soluble proteins from C. albicans grown with either PMS or P. aeruginosa were also red and demonstrated absorbance and fluorescence spectra similar to that of PMS covalently linked to either amino acids or proteins in vitro, suggesting that 5MPCA modification by protein amine groups occurs in vivo. The red-pigmented C. albicans soluble proteins were reduced by NADH and spontaneously oxidized by oxygen, a reaction that likely generates reactive oxygen species (ROS). Additional evidence indicated that ROS generation precedes 5MPCA-induced fungal death. Reducing conditions greatly enhanced PMS uptake by C. albicans and killing. Since 5MPCA was more toxic than other phenazines that are not modified, such as pyocyanin, we propose that the covalent binding of 5MPCA promotes its accumulation in target cells and contributes to its antifungal activity in mixed-species biofilms., (© 2010 Blackwell Publishing Ltd.)

Progressive loss of T cell functionality is a hallmark of chronic infection with human immunodeficiency virus 1 (HIV-1). We have identified a novel population of dysfunctional T cells marked by surface expression of the glycoprotein Tim-3. The frequency of this population was increased in HIV-1-infected individuals to a mean of 49.4 +/- SD 12.9% of CD8(+) T cells expressing Tim-3 in HIV-1-infected chronic progressors versus 28.5 +/- 6.8% in HIV-1-uninfected individuals. Levels of Tim-3 expression on T cells from HIV-1-infected inviduals correlated positively with HIV-1 viral load and CD38 expression and inversely with CD4(+) T cell count. In progressive HIV-1 infection, Tim-3 expression was up-regulated on HIV-1-specific CD8(+) T cells. Tim-3-expressing T cells failed to produce cytokine or proliferate in response to antigen and exhibited impaired Stat5, Erk1/2, and p38 signaling. Blocking the Tim-3 signaling pathway restored proliferation and enhanced cytokine production in HIV-1-specific T cells. Thus, Tim-3 represents a novel target for the therapeutic reversal of HIV-1-associated T cell dysfunction.

Objective: To investigate the relationship between oxidative stress and the underlying causes of infertility, preovulatory ovarian hormones, and ovarian response to gonadotropin stimulation in patients undergoing assisted reproductive techniques., Design: Prospective, cross-sectional study., Setting: Assisted conception unit, university hospital., Patient(s): One hundred thirty women presenting with infertility, of the following types: male factor (n = 56), unexplained (n = 36), tubal factor (n = 16), polycystic ovary syndrome (n = 15), and endometriosis (n = 7)., Intervention(s): Follicular fluid (FF) and peripheral blood samples were collected at oocyte retrieval., Main Outcome Measure(s): Blood and FF samples were analyzed for inhibin A, inhibin B, activin A, anti-Müllerian hormone, and E(2) by using ELISA. Total antioxidant capacity (TAC) was measured in plasma and FF by using a calorimetric microplate assay., Result(s): There was no significant relationship between plasma or FF TAC and the underlying etiology of infertility. There was a statistically significant positive association between FF E(2) levels and TAC (r = 0.26). Higher antral follicle count, delta E(2) (day 3 E(2) minus day 2 E(2)), preovulatory serum anti-Müllerian hormone, inhibin B, and E(2) were associated with good ovarian response, whereas higher FF E(2) was associated with a statistically significant poor response. No significant direct relationship was observed between TAC and ovarian response as well as between TAC or any of the parameters measured and pregnancy outcome., Conclusion(s): Oxidative stress has an impact on the production of granulosa cell steroid hormones, in particular E(2), which is an important predictor of ovarian response. The positive association between FF E(2) and total antioxidant capacity suggests that E(2) may play a role in the ovarian antioxidant-oxidant balance.

Context: Phyllodes tumors (PTs) of the breast are biphasic neoplasms composed of epithelium and a spindle-cell stroma. Currently, PTs are classified as benign, borderline, or malignant based on histopathologic features. However, histologic classification does not always predict outcome. Objective.-To determine the prognostic value of a variety of clinicopathologic features and immunoreactivities in PTs., Design: Sixteen benign, 8 borderline, and 6 malignant PTs with follow-up were examined for reactivity across a panel of immunohistochemical stains, including c-Kit, endothelin 1, p16, p21, p53, and Ki-67. Clinicopathologic features, including stromal cellularity, mitotic rate, and margin status, were also assessed. Tumor variables were compared among tumor subgroups and between tumors that did and did not recur., Results: Of the 30 PTs, 4 recurred (1 benign, 2 borderline, 1 malignant). One patient with a malignant tumor died of metastatic disease 34 months after initial diagnosis. The overall positive rate of c-Kit immunoreactivity was 13% in benign, 63% in borderline, and 67% in malignant PTs. Endothelin 1 epithelial cytoplasmic staining was seen in 100% of benign, 50% of borderline, and 17% of malignant PTs. Additionally, p16, p21, p53, and Ki-67 were differentially expressed among benign, borderline, and malignant tumors. Positive surgical resection margins was the only variable that significantly predicted recurrent disease (P = .02)., Conclusions: Stromal c-Kit positivity and epithelial endothelin 1 negativity are more often associated with malignant PTs; however, only positive margin status is significantly associated with tumor behavior.

Leukocyte type core 2 beta1,6-N-acetylglucosaminyltransferase (C2GnT-L) is a key enzyme in the biosynthesis of branched O-glycans. It is an inverting, metal ion-independent family 14 glycosyltransferase that catalyzes the formation of the core 2 O-glycan (Galbeta1-3[GlcNAcbeta1-6]GalNAc-O-Ser/Thr) from its donor and acceptor substrates, UDP-GlcNAc and the core 1 O-glycan (Galbeta1-3GalNAc-O-Ser/Thr), respectively. Reported here are the x-ray crystal structures of murine C2GnT-L in the absence and presence of the acceptor substrate Galbeta1-3GalNAc at 2.0 and 2.7A resolution, respectively. C2GnT-L was found to possess the GT-A fold; however, it lacks the characteristic metal ion binding DXD motif. The Galbeta1-3GalNAc complex defines the determinants of acceptor substrate binding and shows that Glu-320 corresponds to the structurally conserved catalytic base found in other inverting GT-A fold glycosyltransferases. Comparison of the C2GnT-L structure with that of other GT-A fold glycosyltransferases further suggests that Arg-378 and Lys-401 serve to electrostatically stabilize the nucleoside diphosphate leaving group, a role normally played by metal ion in GT-A structures. The use of basic amino acid side chains in this way is strikingly similar to that seen in a number of metal ion-independent GT-B fold glycosyltransferases and suggests a convergence of catalytic mechanism shared by both GT-A and GT-B fold glycosyltransferases.

The occurrence of mycorrhiza in 40 selected medicinal plants was studied. The percentage of mycorrhizal colonization in each of the plant was calculated. The colonization was found to be very less in four plants and very high in six plants. All others showed a moderate level of colonization. The present work suggests the use of mycorrhiza as a biofertilizer to enhance the growth and yield of medicinal plants.

Gut-associated lymphoid tissues (GALTs) interact with intestinal microflora to drive GALT development and diversify the primary antibody repertoire; however, the molecular mechanisms that link these events remain elusive. Alicia rabbits provide an excellent model to investigate the relationship between GALT, intestinal microflora, and modulation of the antibody repertoire. Most B cells in neonatal Alicia rabbits express V(H)n allotype immunoglobulin (Ig)M. Within weeks, the number of V(H)n B cells decreases, whereas V(H)a allotype B cells increase in number and become predominant. We hypothesized that the repertoire shift from V(H)n to V(H)a B cells results from interactions between GALT and intestinal microflora. To test this hypothesis, we surgically removed organized GALT from newborn Alicia pups and ligated the appendix to sequester it from intestinal microflora. Flow cytometry and nucleotide sequence analyses revealed that the V(H)n to V(H)a repertoire shift did not occur, demonstrating the requirement for interactions between GALT and intestinal microflora in the selective expansion of V(H)a B cells. By comparing amino acid sequences of V(H)n and V(H)a Ig, we identified a putative V(H) ligand binding site for a bacterial or endogenous B cell superantigen. We propose that interaction of such a superantigen with V(H)a B cells results in their selective expansion.

The classification of urothelial neoplasms of the kidney traditionally has been similar to that of urinary bladder tumors. Several years ago, the classification of papillary urothelial neoplasms was revised. The current study focuses on the application of the 1998 World Health Organization (WHO)/International Society of Urological Pathology classification system to 102 renal pelvic urothelial neoplasms and compares it to the 1973 WHO classification scheme. In this study, all tumors were classified as urothelial carcinomas, and the majority (85%) were papillary. Most patients with papillary tumors presented with 'superficial' disease (< or = pT1). With the 1998 system, most papillary carcinomas were high grade, and were more often invasive as compared to low-grade tumors. Only 34% were low-grade papillary tumors and, of these, most (93%) were noninvasive. With the 1973 system, most papillary tumors were grade 2 or 3, with invasion more common in grade 3 tumors. By 1973 criteria, grade 2 tumors were a heterogeneous group; with 1998 criteria, nearly one-half were high grade and the other half low grade. The grade of papillary urothelial carcinomas with both the 1973 and 1998 grading methods was associated with stage (P=0.001). Our study reveals that papillomas and papillary urothelial neoplasms of low malignant potential are uncommon tumors in the kidney. Renal pelvic papillary urothelial neoplasms are most often carcinomas and are more commonly high grade than low grade. Although both the 1973 and 1998 systems showed a significant association with tumor stage, grade 2 papillary carcinomas are a heterogeneous group by 1973 criteria. The 1998 system provides useful information in that it more clearly defines a papillary tumor's grade and selects for a group of tumors, namely low-grade papillary urothelial carcinomas, for which a low likelihood of invasion can be predicted.