160 research outputs found
Surgical Treatment of a Patient with Human Tail and Multiple Abnormalities of the Spinal Cord and Column
The dorsal cutaneous appendage, or so-called human tail, is often considered to be a cutaneous marker of underlying occult dysraphism. The authors present a case of human tail occurring in a 9-month-old infant with multiple abnormalities of the spinal cord and spine. Examination revealed unremarkable except for a caudal appendage and a dark pigmentation area in the low back. Neuroradiological scans revealed cleft vertebrae and bifid ribbon, split cord malformations, block vertebrae, and hemivertebra. Surgical excision of the tail and untethering the spinal cord by removal of the septum were performed. The infant had an uneventful postoperative period and was unchanged neurologically for 18 months of followup. To our knowledge, no similar case reports exist in the literature. The specific features in a rare case with a human tail treated surgically are discussed in light of the available literature
Defining Biological Networks for Noise Buffering and Signaling Sensitivity Using Approximate Bayesian Computation
Reliable information processing in cells requires high sensitivity to changes in the input signal but low sensitivity to random fluctuations in the transmitted signal. There are often many alternative biological circuits qualifying for this biological function. Distinguishing theses biological models and finding the most suitable one are essential, as such model ranking, by experimental evidence, will help to judge the support of the working hypotheses forming each model. Here, we employ the approximate Bayesian computation (ABC) method based on sequential Monte Carlo (SMC) to search for biological circuits that can maintain signaling sensitivity while minimizing noise propagation, focusing on cases where the noise is characterized by rapid fluctuations. By systematically analyzing three-component circuits, we rank these biological circuits and identify three-basic-biological-motif buffering noise while maintaining sensitivity to long-term changes in input signals. We discuss in detail a particular implementation in control of nutrient homeostasis in yeast. The principal component analysis of the posterior provides insight into the nature of the reaction between nodes
A proteomic view of Caenorhabditis elegans caused by short-term hypoxic stress
<p>Abstract</p> <p>Background</p> <p>The nematode <it>Caenorhabditis elegans </it>is both sensitive and tolerant to hypoxic stress, particularly when the evolutionarily conserved hypoxia response pathway HIF-1/EGL-9/VHL is involved. Hypoxia-induced changes in the expression of a number of genes have been analyzed using whole genome microarrays in <it>C. elegans</it>, but the changes at the protein level in response to hypoxic stress still remain unclear.</p> <p>Results</p> <p>Here, we utilized a quantitative proteomic approach to evaluate changes in the expression patterns of proteins during the early response to hypoxia in <it>C. elegans</it>. Two-dimensional difference gel electrophoresis (2D-DIGE) was used to compare the proteomic maps of wild type <it>C. elegans </it>strain N2 under a 4-h hypoxia treatment (0.2% oxygen) and under normoxia (control). A subsequent analysis by MALDI-TOF-TOF-MS revealed nineteen protein spots that were differentially expressed. Nine of the protein spots were significantly upregulated, and ten were downregulated upon hypoxic stress. Three of the upregulated proteins were involved in cytoskeletal function (LEV-11, MLC-1, ACT-4), while another three upregulated (ATP-2, ATP-5, VHA-8) were ATP synthases functionally related to energy metabolism. Four ribosomal proteins (RPL-7, RPL-8, RPL-21, RPS-8) were downregulated, indicating a decrease in the level of protein translation upon hypoxic stress. The overexpression of tropomyosin (LEV-11) was further validated by Western blot. In addition, the mutant strain of <it>lev-11(x12</it>) also showed a hypoxia-sensitive phenotype in subsequent analyses, confirming the proteomic findings.</p> <p>Conclusions</p> <p>Taken together, our data suggest that altered protein expression, structural protein remodeling, and the reduction of translation might play important roles in the early response to oxygen deprivation in <it>C. elegans</it>, and this information will help broaden our knowledge on the mechanism of hypoxia response.</p
The effect of MWA protocols upon morphology and IVIM parameters of hepatic ablation zones—a preliminary in vivo animal study with an MRI-compatible microwave ablation device
PURPOSEWe aimed to explore the effect of microwave ablation (MWA) protocols upon morphology and instant changes in intravoxel incoherent motion (IVIM) diffusion-weighted imaging (DWI) parameters on MWA zones in porcine livers.METHODSAccording to the empirical protocol for MWA in tumors less than 3 cm in our hospital, the power and application duration were assigned as five groups: A, 60 W × 5 min (n = 6); B, 80 W × 3 min (n = 7); C, 80 W × 5 min (n = 10); D, 100 W × 3 min (n = 10); E, 100 W × 5 min (n = 9). Spearman correlation between MWA protocols, morphological metrics, and instant post-ablation IVIM parameters was performed.RESULTSThere was fair positive correlation between energy delivery and short axis (RSpearman = 0.426, P= .005) of the white zone. There was moderate-to-good positive correlation between wattage and short axis (RSpearman = 0.584, P < .001) of the white zone. For post-ablation IVIM parameters in the white zone, only wattage had moderate-to-good positive correlation with D value (RSpearman= 0.574, P < .001) or ADC value (RSpearman = 0.550, P < .001). No correlation between energy delivery, wattage, duration, and f value was observed (RSpearman = 0.185, P = .24; RSpearman= − 0.001, P = .99; RSpearman = 0.203, P = .20, respectively).CONCLUSIONThe increase in the short axis of the white zone is more likely to be affected by wattage than energy delivery. The instant post-ablation IVIM is feasible in monitoring the MWA zones since the f value in the white zones is not sensitive to changes in MWA protocols, which is promising in evaluating the instant effect of MWA
Phases and magnetism at the microscale in compounds containing nominal Pb10-xCux(PO4)6O
Achieving superconductivity at room temperature could lead to substantial
advancements in industry and technology. Recently, a compound known as Cu-doped
lead-apatite, Pb10-xCux(PO4)6O (0.9 < x < 1.1), referred to as "LK-99", has
been reported to exhibit unusual electrical and magnetic behaviors that appear
to resemble a superconducting transition above room temperature. In this work
we collected multiphase samples containing the nominal Pb10-xCux(PO4)6O phase
(no superconductivity observed in our measured samples), synthesized by three
independent groups, and studied their chemical, magnetic, and electrical
properties at the microscale to overcome difficulties in bulk measurements.
Through the utilization of optical, scanning electron, atomic force, and
scanning diamond nitrogen-vacancy microscopy techniques, we are able to
establish a link between local magnetic properties and specific microscale
chemical phases. Our findings indicate that while the Pb10-xCux(PO4)6O phase
seems to have a mixed magnetism contribution, a significant fraction of the
diamagnetic response can be attributed to Cu-rich regions (e.g., Cu2S derived
from a reagent used in the synthesis). Additionally, our electrical
measurements reveal the phenomenon of current path switch and a change in
resistance states of Cu2S. This provides a potential explanation for the
electrical behavior observed in compounds related to Pb10-xCux(PO4)6O.Comment: 14 pages, 5 figures; Physical Review Material
CKD-TransBTS: Clinical Knowledge-Driven Hybrid Transformer with Modality-Correlated Cross-Attention for Brain Tumor Segmentation
Brain tumor segmentation (BTS) in magnetic resonance image (MRI) is crucial
for brain tumor diagnosis, cancer management and research purposes. With the
great success of the ten-year BraTS challenges as well as the advances of CNN
and Transformer algorithms, a lot of outstanding BTS models have been proposed
to tackle the difficulties of BTS in different technical aspects. However,
existing studies hardly consider how to fuse the multi-modality images in a
reasonable manner. In this paper, we leverage the clinical knowledge of how
radiologists diagnose brain tumors from multiple MRI modalities and propose a
clinical knowledge-driven brain tumor segmentation model, called CKD-TransBTS.
Instead of directly concatenating all the modalities, we re-organize the input
modalities by separating them into two groups according to the imaging
principle of MRI. A dual-branch hybrid encoder with the proposed
modality-correlated cross-attention block (MCCA) is designed to extract the
multi-modality image features. The proposed model inherits the strengths from
both Transformer and CNN with the local feature representation ability for
precise lesion boundaries and long-range feature extraction for 3D volumetric
images. To bridge the gap between Transformer and CNN features, we propose a
Trans&CNN Feature Calibration block (TCFC) in the decoder. We compare the
proposed model with five CNN-based models and six transformer-based models on
the BraTS 2021 challenge dataset. Extensive experiments demonstrate that the
proposed model achieves state-of-the-art brain tumor segmentation performance
compared with all the competitors
A New pseudo-Alkaloid Taxane and a New Rearranged Taxane from the Needles of Taxus canadensis
A new taxane with an amino side chain on C-5 and a new 11(15→1)abeotaxane having a tetrahydrofuran ring along carbon atoms C-2, C-3, C-4, C-20 identified for the first time from the needles of the Canadian yew, Taxus canadensis. Their structures were characterized as 2α,7β ,9α,10β ,13-pentaacetoxy-11β -hydroxy-5α-(2 -hydroxy,3 -N,N-dimethylamino-3 -phenyl)-propionyloxytaxa-4(20),12-diene (1) and 13α,20β -diacetoxy-5α,7β ,9α,10β -tetrahydroxy-2α,20-epoxy-11(15→1)abeotaxa-11,15-diene (2) on the basis of 1D, 2D NMR spectroscopy and high-resolution FABMS analysis. Taxane 1 contains a rare C-12, C-13 double bond and a basic side chain, while taxane 2 bears a rare isopropenyl group at C-1
HoVer-Trans: Anatomy-aware HoVer-Transformer for ROI-free Breast Cancer Diagnosis in Ultrasound Images
Ultrasonography is an important routine examination for breast cancer
diagnosis, due to its non-invasive, radiation-free and low-cost properties.
However, the diagnostic accuracy of breast cancer is still limited due to its
inherent limitations. It would be a tremendous success if we can precisely
diagnose breast cancer by breast ultrasound images (BUS). Many learning-based
computer-aided diagnostic methods have been proposed to achieve breast cancer
diagnosis/lesion classification. However, most of them require a pre-define ROI
and then classify the lesion inside the ROI. Conventional classification
backbones, such as VGG16 and ResNet50, can achieve promising classification
results with no ROI requirement. But these models lack interpretability, thus
restricting their use in clinical practice. In this study, we propose a novel
ROI-free model for breast cancer diagnosis in ultrasound images with
interpretable feature representations. We leverage the anatomical prior
knowledge that malignant and benign tumors have different spatial relationships
between different tissue layers, and propose a HoVer-Transformer to formulate
this prior knowledge. The proposed HoVer-Trans block extracts the inter- and
intra-layer spatial information horizontally and vertically. We conduct and
release an open dataset GDPH&SYSUCC for breast cancer diagnosis in BUS. The
proposed model is evaluated in three datasets by comparing with four CNN-based
models and two vision transformer models via five-fold cross validation. It
achieves state-of-the-art classification performance with the best model
interpretability. In the meanwhile, our proposed model outperforms two senior
sonographers on the breast cancer diagnosis when only one BUS image is given
Prognostic Value of Germline Copy Number Variants and Environmental Exposures in Non-small Cell Lung Cancer
Germline copy number variant (gCNV) has been studied as a genetic determinant for prognosis of several types of cancer, but little is known about how it affects non-small cell lung cancer (NSCLC) prognosis. We aimed to develop a prognostic nomogram for NSCLC based on gCNVs. Promising gCNVs that are associated with overall survival (OS) of NSCLC were sorted by analyzing the TCGA data and were validated in a small Chinese population. Then the successfully verified gCNVs were determined in a training cohort (n = 570) to develop a prognostic nomogram, and in a validation cohort (n = 465) to validate the nomogram. Thirty-five OS-related gCNVs were sorted and were reduced to 15 predictors by the Lasso regression analysis. Of them, only CNVR395.1 and CNVR2239.1 were confirmed to be associated with OS of NSCLC in the Chinese population. High polygenic risk score (PRS), which was calculated by the hazard effects of CNVR395.1 and CNVR2239.1, exerted a significantly higher death rate in the training cohort (HR = 1.41, 95%CI: 1.16–1.74) and validation cohort (HR = 1.42, 95%CI: 1.13–1.77) than low PRS. The nomogram incorporating PRS and surrounding factors, achieved admissible concordance indexes of 0.678 (95%CI: 0.664–0.693) and 0.686 (95%CI: 0.670–0.702) in predicting OS in the training and validation cohorts, respectively, and had well-fitted calibration curves. Moreover, an interaction between PRS and asbestos exposure was observed on affecting OS (Pinteraction = 0.042). Our analysis developed a nomogram that achieved an admissible prediction of NSCLC survival, which would be beneficial to the personalized intervention of NSCLC
Screening of an individualized treatment strategy for an advanced gallbladder cancer using patient-derived tumor xenograft and organoid models
Gallbladder cancer is a highly aggressive malignancy with poor sensitivity to postoperative radiotherapy or chemotherapy; therefore, the development of individualized treatment strategies is paramount to improve patient outcomes. Both patient-derived tumor xenograft (PDX) and patient-derived tumor organoid (PDO) models derived from surgical specimens can better preserve the biological characteristics and heterogeneity of individual original tumors, display a unique advantage for individualized therapy and predicting clinical outcomes. In this study, PDX and PDO models of advanced gallbladder cancer were established, and the consistency of biological characteristics between them and primary patient samples was confirmed using pathological analysis and RNA-sequencing. Additionally, we tested the efficacy of chemotherapeutic drugs, targeted drugs, and immune checkpoint inhibitors using these two models. The results demonstrated that gemcitabine combined with cisplatin induced significant therapeutic effects. Furthermore, treatment with immune checkpoint inhibitors elicited promising responses in both the humanized mice and PDO immune models. Based on these results, gemcitabine combined with cisplatin was used for basic treatment, and immune checkpoint inhibitors were applied as a complementary intervention for gallbladder cancer. The patient responded well to treatment and exhibited a clearance of tumor foci. Our findings indicate that the combined use of PDO and PDX models can guide the clinical treatment course for gallbladder cancer patients to achieve individualized and effective treatment
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