Automated Small Tumor Segmentation by a Template-Based Global Hierarchical Attention Method

PURPOSE/OBJECTIVE(S)

Accurate segmentation of tumors is significant for radiation therapy treatment planning and clinical decision-making. While deep convolutional neural network-based methods have found valuable applications in automatic medical segmentation, tumor segmentation, especially small tumor segmentation, remains challenging due to deficiencies of current deep learning in convolutional and pooling operations, which often results in the loss of small object information. This research proposes a global hierarchical attention-based method for accurate and automated segmentation of small tumors by exploiting the associations between small tumors and the feature maps of large tumors.

MATERIALS/METHODS

This study included 131 patients with liver cancer. The in-plane resolution of the patients' CTs is from 0.55 mm to 1.0 mm and slice spacing from 0.45 mm to 6.0 mm. We randomly selected 100 CT scans as the training set and others as the testing set. Each CT slice of the testing set was separated into groups according to tumor size as follows: 0.1-2.0, 2.1-5.0, 5.1-10.0, and 10.1-20.0 cm. The CT slice without tumor or tumor size > 20 cm were excluded. This work presents a tumor template-based hierarchical attention method to quantify the relation between small and large tumors by computing their feature maps. The relation of small-large tumors can compensate for the information loss of small tumors during the convolutional and pooling operations and improve the performance of small tumor segmentation.

RESULTS

Among 20,693 CT slices of the 31 testing patients, 3.0% CT slices with tumors ≤2 cm, 6.7% ≤5 cm, 10.6% ≤10 cm, and 13.4%≤20 cm. We compared our method with six widely used segmentation models. The results show our model outperforms other methods on all sizes of liver tumors, especially for small size tumors: For the 0.1-2.0 cm liver tumor, it achieved 8.4%, 10.0%, 11.3%, 9.1%, 10.9%, and 9.6% improvement compared to Unet, PAN, DeepLabV3, FPN, LinkNet, and PSPNet, respectively.

CONCLUSION

We found that the small-large tumors relation can significantly improve small tumor segmentation, which is valuable for treatment planning, and clinical decision-making. Our experimental results show that our method can significantly improve the accuracy of segmenting small liver tumors compared to existing deep-learning-based models. The method is quite general and can be extended to other types of tumor detection and segmentation. We discovered that the relationship between small and large tumors can significantly enhance the segmentation of small tumors, which has significant value for treatment planning and clinical decision-making. Our experiments demonstrate that our approach significantly improves the accuracy of small liver tumor segmentation compared to existing deep learning-based models. Our method is quite versatile and can be extended to other types of tumor detection and segmentation.

Prevalence and cardiovascular risk factors of asymptomatic intracranial arterial stenosis: the Kongcun Town Study in Shandong, China

BACKGROUND AND PURPOSE

This study was to investigate the prevalence and cardiovascular risk factors (CRFs) of asymptomatic intracranial atherosclerotic stenosis (aICAS) amongst middle-aged and older adults living in rural communities in China.

METHODS

This population-based study included 2019 subjects (aged ≥40 years, 52.3% women) who were free of stroke and living in rural communities in China. From October 2017 to May 2018, data on demographics, CRFs and health conditions were collected through face-to-face interviews, physical examination and laboratory tests. Asymptomatic ICAS was detected through a two-phase procedure: a screening phase with transcranial Doppler ultrasound, followed by a diagnostic phase with magnetic resonance angiography examination. Multivariable logistic regression models were used to analyse CRFs associated with aICAS.

RESULTS

Of the 2019 participants, aICAS was detected in 153 persons. The overall prevalence of aICAS was 7.6%, and the prevalence of moderate-to-severe aICAS was 5.0%. The multi-adjusted odds ratio (95% confidence interval) of aICAS associated with CRFs was 2.40 (1.56-3.69) for hypertension, 1.91 (1.32-2.76) for high hypersensitive C-reactive protein, 1.68 (1.14-2.49) for diabetes and 1.61 (1.08-2.41) for overweight or obesity. When these four CRFs were aggregated, compared with participants without any of these factors, the multi-adjusted odds ratios (95% confidence interval) of aICAS for persons concurrently having one, two and three or more of these factors were 1.14 (0.52-2.48), 2.91 (1.42-5.99) and 5.51 (2.64-11.50), respectively (P for linear trend <0.001).

CONCLUSIONS

Asymptomatic ICAS is common amongst rural-dwelling middle-aged and older Chinese people. Hypertension, diabetes, overweight or obesity and high hypersensitive C-reactive protein, especially when coexisting, are strongly associated with aICAS.

Characterization of the triterpene saponins of the roots and rhizomes of blue cohosh (Caulophyllum thalictroides)

Seven triterpene saponins were isolated from n-butanol fractions of blue cohosh (Caulophyllum thalictroides) roots and rhizomes. Their structures were established by spectral ((1)H NMR, (13)C NMR, 2D-NMR, and APCI-MS) techniques and chemical reactions as hederagenin 3-O-alpha-L-arabinopyranoside (1); caulophyllogenin 3-O-alpha-L-arabinopyranoside (2); hederagenin 3-O-beta-D-glucopyranosyl-(1-->2)-alpha-L-arabinopyranoside (3); 3-O-alpha-L-arabinopyranosyl-hederagenin 28-O-alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl(1-->6)-beta-D-glucopyranoside (4); 3-O-alpha-L-arabinopyranosyl- caulophyllogenin 28-O-alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl(1-->6)-beta-D-glucopyranoside (5); 3-O-beta-D-glucopyranosyl-(1-->2)-alpha-L-arabinopyranosyl- echinocystic acid 28-O-alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl(1-->6)-beta-D-glucopyranoside (6); 3-O-beta-D-glucopyranosyl-(1-->2)-alpha-L-arabinopyranosyl-hederagenin 28-O-alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl(1-->6)-beta-D-glucopyranoside (7). All seven compounds were identified in this species for the first time.

Furanosesquiterpenoids of Commiphora myrrha

An investigation on the gum exudates of Commiphora myrrha has led to the isolation of six sesquiterpenoids. On the basis of spectroscopic data interpretation, they were determined as two new furanosesquiterpenoids, rel-1S,2S-epoxy-4R-furanogermacr-10(15)-en-6-one (1) and rel-2R-methyl-5S-acetoxy-4R-furanogermacr-1(10)Z-en-6-one (2), and four known furanosesquiterpenoids, rel-3R-methoxy-4S-furanogermacra-1E,10(15)-dien-6-one (3), rel-2R-methoxy-4R-furanogermacr-1(10)E-en-6-one (4), furanogermacra-1(10)Z,4Z-dien-6-one, and curzerenone [6,7-dihydro-5beta-isopropenyl-3,6beta-dimethyl-6-vinylbenzofuran-4(5H)-one]. This is the first report of the relative stereochemistry for the known compounds 3 and 4. Compound 1 exhibited weak cytotoxic activity against a MCF-7 breast tumor cell line in a clonogenic assay, while the other five compounds were inactive in this assay.

New spirostanol saponins from Chinese chives (Allium tuberosum)

Three new spirostanol saponins have been isolated from the seeds of Allium tuberosum. On the basis of acid hydrolysis and comprehensive spectroscopic analysis, their structures were established as tuberoside J, (25R)-5alpha-spirostan-2alpha,3beta,27-triol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside; tuberoside K, (25R)-5alpha-spirostan-2alpha,3beta,27-triol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-[alpha-L-rhamnopyranosyl-(1-->4)]-beta-D-glucopyranoside; and tuberoside L, 27-O-beta-D-glucopyranosyl-(25R)-5alpha-spirostan-2alpha,3beta,27-triol 3-O-alpha-D-rhamnopyranosyl-(1-->2)-[alpha-L-rhamnopyranosyl-(1-->4)]-beta-D-glucopyranoside.

Flavonol glycosides and novel iridoid glycoside from the leaves of Morinda citrifolia

One new iridoid glycoside and five known flavonol glycosides have been isolated from the leaves of Morinda citrifolia. The new iridoid exists as an epimeric mixture in solution. Complete assignments of the proton and carbon chemical shifts for the individual epimers were accomplished on the basis of high-resolution 1D and 2D NMR data. Their antioxidative activities were measured. All of these compounds showed DPPH free radical scavenging activity at the concentration of 30 microM.

Two novel glycosides from the fruits of Morinda citrifolia (noni) inhibit AP-1 transactivation and cell transformation in the mouse epidermal JB6 cell line

The fruit juice of Morinda citrifolia (noni), a plant originally grown in the Hawaiian and Tahitian islands, has long been used by islanders to treat diseases, including cancer. Two novel glycosides, 6-O-(beta-D-glucopyranosyl)-1-O-octanoyl-beta-D-glucopyranose and asperulosidic acid, extracted from the juice of noni fruits, were used to examine their effects on 12-O-tedtradecanoylphorbol-13-acetate (TPA)- and epidermal growth factor (EGF)-induced AP-1 transactivation and cell transformation in mouse epidermal JB6 cells. The results indicated that both compounds were effective in suppressing TPA- or EGF-induced cell transformation and associated AP-1 activity. TPA- or EGF-induced phosphorylation of c-Jun, but not extracellular signal-regulated kinases or p38 kinases, was also blocked by the compounds, indicating that c-Jun N-terminal kinases were critical in mediating TPA- or EGF-induced AP-1 activity and subsequent cell transformation in JB6 cells.

Cord blood levels of interleukin-6 and interleukin-8 for the immediate diagnosis of early-onset infection in premature infants

BACKGROUND

Cytokine plasma levels are suggested to be sensitive indicators of neonatal sepsis, but conventional assays are time consuming. This study aimed at evaluating the significance of cord blood levels of interleukin (IL)-6 and IL-8 determined by a fully automated random access assay within 90 min of admission to predict systemic bacterial infection.

PATIENTS AND METHODS

Cord blood levels of IL-6 and IL-8 were determined in 71 mature and 100 premature infants by a chemiluminescence assay (Immulite). Patients were divided into four groups according to a clinical and laboratory scoring system. Group A: documented early-onset infection; group B: infection possible; group C: infection unlikely, and group D: healthy newborns.

RESULTS

Median IL-6 levels in the subgroup of premature newborns were as follows: group A, 1,920 pg/ml (5-95% confidence interval 308-4,660 pg/ml); group B, 50 (15-102) pg/ml; group C, 21 (12-71) pg/ml, and group D, 8 (6-11) pg/ml. For IL-8, median levels for groups A-D were 289 (226-514) pg/ml, 87 (40-107) pg/ml, 44 (33-98) pg/ml and 21 (16-25) pg/ml, respectively. The difference between group A and the other groups was highly significant (IL-6 p < 0.0001, IL-8 p < 0.001). At a cut-off of 80 pg/ml, the sensitivity of IL-6 for the diagnosis of sepsis was 96% (specificity 95%). For IL-8 (cut-off 90 pg/ml), the sensitivity was 87% (specificity 94%).

CONCLUSION

In premature infants, the diagnosis of an early-onset infection can be established or ruled out with a high level of confidence by measuring IL-6 or IL-8 levels from cord blood using a random access chemiluminescence assay.

A new unusual iridoid with inhibition of activator protein-1 (AP-1) from the leaves of Morinda citrifolia L

[structure in text] From the leaves of Morinda citrifolia, a new unusual iridoid, named citrifolinoside (1), showing significant inhibition of UVB-induced Activator Protein-1 (AP-1) activity in cell cultures, has been isolated. Its structure was elucidated on the basis of detailed high-field 1D and 2D spectral analysis.

Iridoid glycosides from the leaves of Morinda citrifolia

A new iridoid glucoside (1), named citrifolinoside A, was isolated from the leaves of Morinda citrifolia along with the known iridoids asperuloside and asperulosidic acid. The structure of 1 was established by interpretation and full assignments of NMR spectroscopic data.

Formation and identification of 4'-O-methyl-(-)-epigallocatechin in humans

The possible beneficial effects of tea consumption have attracted a great deal of attention. Many of the biological effects have been attributed to tea catechins, but the metabolic fate of these compounds is not clear. In the present study, a major metabolite observed in human blood and urine samples after green tea administration was identified as a O-methylated derivative of (-)-epigallocatechin (EGC) by comparison with products from chemical and enzymatic O-methylation of EGC. The structure of this metabolite was elucidated as 4'-O-methyl-(-)-epigallocatechin (4'-O-MeEGC) by (1)H and (13)C NMR and heteronuclear multiple bond connectivity experiment. The human plasma level of 4'-O-MeEGC reached its peak value within the first 2 h following tea ingestion. Its maximum concentration was 4 to 6 times higher than that of EGC. The half-lives of EGC and 4'-O-MeEGC in the blood were 1.02 +/- 0.07 and 4.39 +/- 1.14 h, respectively. The amount of 4'-O-MeEGC excreted in urine was about 3 times higher than that of EGC, and 88% of 4'-O-MeEGC was excreted in urine within 8 h. The present structural information and concentration-time profile of this metabolite provide the basis for understanding the biotransformation of EGC and for future elucidation of its biological activities.

Four new steroidal saponins from the seeds of Allium tuberosum

Four new steroidal saponins, 26-O-beta-D-glucopyranosyl-(25S,20R)-20-O-methyl-5alpha-furost-22(23)-en-2alpha,3beta,20,26-tetraol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-[alpha-L-rhamnopyranosyl-(1-->4)]-beta-D-glucopyranoside (1); 26-O-beta-D-glucopyranosyl-(25S,20R)-5alpha-furost-22(23)-en-2alpha,3beta,20,26-tetraol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-[alpha-L- rhamnopyranosyl-(1-->4)]-beta-D-glucopyranoside (2); 26-O-beta-D-glucopyranosyl-(25S,20S)-5alpha-furost-22(23)-en-2alpha,3beta,20,26-tetraol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-[alpha-L- rhamnopyranosyl-(1-->4)]-beta-D-glucopyranoside (3); and 26-O-beta-D-glucopyranosyl-(25S,20S)-5alpha-furost-22(23)-en-3beta,20,26-triol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-[alpha-L-rhamnopyranosyl-(1-->4)]-beta-D-glucopyranoside (4), have been isolated from the seeds of Allium tuberosum. Their structures were established by spectroscopic studies such as MS, IR, NMR, and 2D-NMR and the results of acid hydrolysis and named tuberosides F, G, H, and I, respectively.

Isolation and structural elucidation of two new glycosides from sage (Salvia officinalis L.)

Six compounds, 1-O-(2,3, 4-trihydroxy-3-methyl)butyl-6-O-feruloyl-beta-D-glucopyranoside, ethyl beta-D-glucopyranosyl tuberonate, p-hydroxybenzoic acid, (-)-hydroxyjasmonic acid, caffeic acid, and 4-hydroxyacetophenone 4-O-[5-O-(3, 5-dimethoxy-4-hydroxybenzoyl)-beta-D-apiofrunosyl]-(1-->2)-beta-D- glu copyranoside, were isolated from the n-butanol-soluble fraction of sage leaf extracts. Their structures were determined by spectral methods (MS, NMR, and 2D-NMR), and their antioxidant activities were measured. Among them, two new glycosides were elucidated. All of these compounds showed DPPH free radical scavenging activity at the concentration of 30 mM, and caffeic acid was the most active compound.

Two new spirostanol saponins from Allium tuberosum

Two new spirostanol saponins, tuberosides D and E, have been isolated from the seeds of Allium tuberosum. On the basis of spectral data and chemical reactions, their structures were established as (25S)-5alpha-spirostane-2alpha,3beta-diol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-O-[alpha-L-rhamnopyranosyl-(1-->4 )]-O-beta-D-glucopyranoside and (25S)-5alpha-spirostan-2alpha, 3beta-diol 3-O-beta-D-glucopyranosyl-(1-->2)-O-[alpha-L-rhamnopyranosyl-(1-->4)] -O-beta-D-glucopyranoside, respectively.

Triterpenoid saponins from Vaccaria segetalis

A new triterpenoid saponin, named segetoside C (1), and two known saponins, vaccaroid A (vaccaroside A) (2) and dianoside G (3), have been isolated from the seeds of Vaccaria segetalis. On the basis of chemical reaction and spectral data, the structure of segetoside C (1) has been established as: gypsogenic acid-28-O-[beta-D-glucopyranosyl-(1-->3)]-[6-O-acetyl-beta-D-glucopyra-nosyl-(1-->2)-beta-D-glucopyranosyl-(1-->6)]-beta-D-glucopyranoside.