Tumor Voxel Dose-Response Matrix Prediction Using Deep Learning

PURPOSE/OBJECTIVE(S)

Tumor voxel dose-response matrix (DRM) can be assessed using a series of FDG-PET/CT feedback images acquired during radiotherapy. Predicting the tumor voxel DRM earlier is crucial for effectively implementing adaptive treatment management. However, it is also challenging due to FDG uptake dynamic fluctuation in tumor cells. This study investigated the feasibility of predicting tumor voxel DRM during the early treatment weeks using the advanced deep learning (DL) technique.

MATERIALS/METHODS

Serial FDG-PET/CT images were acquired at the pretreatment (pre-Tx), the 2nd and 4th treatment weeks during standard chemo-radiotherapy (35 × 2 Gy) from each of the 50 patients with head and neck squamous cell carcinomas (HNSCC). The reference value of tumor voxel DRM (DRMref), representing the average metabolic change ratio during the treatment, was determined using a linear regression performed on the standard uptake values (SUV)s obtained at the pre-Tx (SUV0), the 2nd (SUV2) and the 4th (SUV4) treatment weeks following deformable PET/CT image registration. A DL model, 3D residual-Unet with a total of 3.4 million parameters, was trained to predict the tumor voxel DRMref with using the SUV0 and SUV2 matrices as inputs. The performance of the DL model was evaluated using 10-fold cross-validation and was compared to that of a linear regression (LR) model determined on the SUV0 and SUV2 matrices.

RESULTS

The mean (SD) of the tumor voxel DRMref was 0.46 (0.2) over all 34612 tumor voxels. The predicted tumor voxel DRM was 0.5 (0.38) and 0.46 (0.15) for the LR model and the DL model, respectively. For those resistant voxels (23.7% of all tumor voxels) with a DRMref > 0.6, the DRM deviation was 0.13 (0.4) and -0.11 (0.13) for the LR model and the DL model, respectively. For those sensitive voxels (76.3%) with a DRMref ≤ 0.6, the DRM deviation was 0.01 (0.23) and 0.03 (0.08) for the LR model and the DL model, respectively.

CONCLUSION

The proposed DL model can predict the tumor voxel DRM with a single FDG-PET feedback image acquired during the 2nd treatment week of radiotherapy for HNSCC patients. The prediction accuracy was improved compared to that of the LR model with a substantial reduction in the variances of the prediction errors. This work demonstrates the great potential of utilizing DL techniques to improve the efficiency of tumor response assessment and adaptive treatment management.

Adaptive Radiotherapy with Dose Fractionation Painting

PURPOSE/OBJECTIVE(S)

Efficacy of dose fractionation is dependent on tumor radiosensitivity. However, due to intra-tumoral dose response heterogeneity, the advantage of fractionation cannot be fully utilized. FDG-PET/CT has been used to assess intra-tumoral dose response during the treatment course. Thus, radiosensitivity of different sub-volumes within the individual tumors can be assessed and used to design dose fractionation.

MATERIALS/METHODS

For each patient, the pre-treatment FDG-PET/CT and a feedback FDG-PET/CT obtained within the 3rd week of the chemo-radiotherapy for HN cancer were used to construct tumor voxel dose response matrix, DRM. Biologically equivalent dose EQD2 was determined using the DRM and assuming relative stability of the radiation double-hit effect, meanwhile normal tissue EQD2 was determined assuming the corresponding α/β = 3.0. Tumor voxel EQD2 ratio was calculated with a given limitation of normal tissue EQD2 and used to determine tumor voxel fractionation (Table). Tumor was divided into few sub-volumes based on ranges of the tumor voxel DRM value. Different fractionation doses, but same number of fractions, were selected to ensure that the planning dose distribution can be simultaneously delivered.

RESULTS

Table shows the EQD2 of tumor voxel DRM for each given fractionation and normal tissue dose limitation. The treatment dose efficiency increases exponentially as increasing dose per fraction for those of resistant tumor voxels, i.e., DRM > = 0.7. The 2 Gy per fraction was used within the first 3 treatment weeks before tumor voxel dose response assessed. After the 15 fractions, tumor voxel dose fractionation will be adjusted with respect to its DRM and the expected treatment dose. Typically, 3 sub-volumes for each resistant tumor were segmented and designed with 3 fractionation regimens. With respect to normal tissue EQD2 constraint < = 70 Gy, the corresponding EQD2 was 55 ∼ 73 Gy for tumor sub-volume with DRM = 0.1 ∼ 0.6; 77 ∼ 90 Gy for tumor sub-volume with DRM = 0.65 ∼ 0.75; > 101 Gy for tumor sub-volume with DRM > = 0.8 respectively. For very resistant tumor cells i.e., DRM > 0.9, the EQD2 > 160 Gy can be achieved or > 244 Gy if the normal tissue EQD2 constraint can be relaxed to 90 Gy for the small resistant tumor sub-volume. For the study patients, tumor sub-volume with DRM > 0.9 = 0.128 ∼ 7.4cc.

CONCLUSION

Adaptive dose fractionation painting can be achieved followed by the dose response assessment. Dependent on the size and location of resistant tumor sub-volumes, tumor EQD2 could be largely improved without increasing normal tissue dose.

Tumor Treatment Response Assessed During the Concurrent Chemoradiotherapy for Nasopharyngeal Patients

PURPOSE/OBJECTIVE(S)

To evaluate intratumoral treatment response distribution with using FDG-PET/CT during the chemoradiotherapy of nasopharyngeal patients (NPC).

MATERIALS/METHODS

A total of 5 of 30 patients with stage III-IVA NPC were enrolled in the institutional protocol for induction/concurrent chemoradiotherapy with radiation dose of 70 Gy in 33 fractions. For each patient, a pre-radiation treatment FDG-PET/MRI image (SUV0) and a mid-treatment image (SUVm) at the treatment dose of 31.8 Gy were obtained. Followed by deformable PET/MRI registration between SUV0 and SUVm, the tumor voxel SUV reduction ratio was obtained to construct a tumor dose response matrix (DRM). Tumor SUVavid was also constructed by limiting tumor voxel SUVm > a given value. Spatial correlations of the tumor SUV0, SUVm, SUVavid and DRM were determined.

RESULTS

The mean and coefficient variation (CV) of the SUV0, SUVm and DRM for all tumors were 5.05 (52%), 2.72 (49%) and 0.64 (63%) (Table contains the individual data), which were smaller than those on the SUVs of head-n-neck HPV+ patients reported previously due to the induction chemotherapy, but had much larger DRM mean and CV. The inter-tumoral CVs of SUV0 and DRM were 29% and 27%, which were much lower than those of the intra-tumoral CVs 43% and 57%. Meanwhile, the intra-tumoral variations on SUV0 was smaller than the one of head-neck HPV+ patients, but the DRM intra-variation was much larger. There was a weak correlation between SUV0 and SUVm with the correlation coefficient 0.13, a medium correlation of -0.55 between SUV0 and DRM, but a strong correlation, 0.72, between SUVm and DRM. However, the spatial correlation between tumor DRM and SUVavid was getting weaker as the SUVavid value increasing and equal 0.47 with SUVavid value > 3.

CONCLUSION

The spatial dose response DRM for NPC in the concurrent chemoradiotherapy was relatively high, while had relatively low baseline tumor metabolic activity SUV0. It was most likely due to the induction chemotherapy. In addition, the tumor dose response showed vary large intra-tumoral variation. The high correlations between DRM and SUVm imply that SUVavid could be used partially to guide adaptive modification of NPC treatment with carefully selected boundary value.

Tumor Treatment Response Assessed During the Chemo-Radiotherapy for Locally Advanced NSCLC

PURPOSE/OBJECTIVE(S)

To evaluate the capability of assessing intratumoral treatment response distribution with using FDG-PET/CT during the chemoradiotherapy of locally advanced NSCLC.

MATERIALS/METHODS

Twelve of total 50 patients with stage III NSCLC were enrolled in the institutional protocol for concurrent chemoradiotherapy with treatment dose of 54-60 Gy in 27-30 fractions. For each patient, a pre-treatment FDG-PET/CT image (SUV0) and a mid-treatment image (SUVm) obtained within the treatment dose of 24 ∼ 46 Gy were obtained. Followed by deformable PET/CT registration between SUV0 and SUVm, the tumor voxel SUV reduction ratio was obtained to construct a tumor dose response matrix (DRM). Tumor SUVavid was also constructed by limiting tumor voxel SUVm > a given value. Spatial correlations of the tumor SUV0, SUVm, SUVavid and DRM were determined.

RESULTS

The mean and coefficient variation (CV) of the SUV0, SUVm and DRM for all tumors were 6.56(64%), 2.82(59%) and 0.52(70%) (Table contains the individual data), which were like those on the SUVs and the mean DRM of head-neck HPV- patients reported previously, but much larger on the DRM variation. The inter-tumoral CVs of SUV0 and DRM were 17% and 43%, which were much smaller than those of the intra-tumoral CVs 61% and 55%. Meanwhile, the intra-tumoral variations on both SUV0 and DRM were much larger than those of head-neck HPV- patients. There was a weak correlation between SUV0 and SUVm with the correlation coefficient 0.32, a medium correlation of -0.51 between SUV0 and DRM; 0.58 between SUVm and DRM. It implies that the rule of tumor dose response DRM on treatment modification decision cannot be fully replaced by either SUV0 or SUVm. The spatial correlation between tumor DRM and SUVavid was 0.23 with SUVavid value > 3, which was getting weaker when increasing SUVavid value.

CONCLUSION

Spatial dose response for NSCLC assessed using FDG-PET/CT feedback demonstrated high treatment resistant patterns, which had a large intra-tumoral variation. In addition, the medium correlations of DRM vs SUV0 and DRM vs SUVm imply that all these factors could be used to guide adaptive modification of NSCLC treatment.

Hybrid Immuno-RT for Bulky Tumors: Standard Fractionation with Partial Tumor SBRT

PURPOSE/OBJECTIVE(S)

Bulky tumors remain challenging to be treated. Stereotactic body radiation therapy (SBRT) is effective against radioresistant tumor cells and can induce immunogenic cell death (ICD) that leads to T-cell-mediated antitumor effects. Low-dose radiation (LDRT) can inflame the tumor microenvironment (TME) by recruiting T cells. We designed a novel radiotherapy technique (RT, ERT) whose dose distribution map resembles the "eclipse" by concurrently delivering LDRT to the whole tumor, meanwhile SBRT to only a part of the same tumor. This study examined the safety and efficacy of ERT to bulky lesions with PD-1 inhibitors in mice and patients.

MATERIALS/METHODS

In mice with CT26 colon or LLC1 lung bulky tumors (400 - 500 cm3), the whole tumor was irradiated by LDRT (2 Gy x 3), meanwhile the tumor center was irradiated by SBRT (10 Gy x 3); αPD-1 was given weekly. The dependence of therapeutic effects on CD8+ T cells was determined using depleting antibodies. Frequencies of CD8+ T cells and M1 macrophages (Mφ) were determined by flow cytometry. Multiplex Immunohistochemistry (mIHC) was applied to analyze the number and the location of CD8+ T cells and their subpopulations, as well as the phospho-eIF2α level (the ICD marker) of tumor cells in TME. Patients with advanced lung or liver bulky tumors who failed standard treatment or with oncologic emergencies were treated. Kaplan-Meier method was applied to estimate patients' progression-free survival (PFS) and overall survival (OS).

RESULTS

ERT/αPD-1 is superior to SBRT/αPD-1 or LDRT/αPD-1 in controlling bulky tumors in both mouse models in a CD8+ T-cell dependent manner. In the CT26 model, ERT/αPD-1 resulted in complete tumor regression in 3/11 mice and induced more CD8+ T cells and M1 Mφ in TME compared to other groups. mIHC analysis showed that ERT/αPD-1 induced higher bulk, stem-like (TCF1+ TIM3- PD-1+), and more differentiated (TCF1- TIM3+ PD-1+) CD8+ T cells infiltration into the tumor center and periphery compared to other groups. Compared to untreated or LDRT-treated tumor centers, tumor centers irradiated with ERT or SBRT showed elevated phospho-eIF2α accompanied by higher dendritic cell infiltration. In total, 39 advanced cancer patients were treated with ERT/αPD-1 or plus chemotherapy. Radiation-induced pneumonitis occurred in 1 of 26 patients receiving thoracic ERT. There were two cases of grade III toxicity associated with PD-1 inhibitors. No toxicity above grade III was observed. The objective response rate was 38.5%. The median PFS was 5.6 months and median OS was not reached at a median follow-up of 11.7 months.

CONCLUSION

ERT/αPD-1 showed superior efficacy in controlling bulky tumor in two mouse models. The hybrid immuno-RT (ERT) combing PD-1 inhibitors was safe and effective in patients with bulky tumors. Further clinical trials in combination with bioimaging to identify the optimal SBRT target region for the bulky tumor are warranted.

Extended p_{3/2} Neutron Orbital and the N=32 Shell Closure in ^{52}Ca

The one-neutron knockout from ^{52}Ca in inverse kinematics onto a proton target was performed at ∼230  MeV/nucleon combined with prompt γ spectroscopy. Exclusive quasifree scattering cross sections to bound states in ^{51}Ca and the momentum distributions corresponding to the removal of 1f_{7/2} and 2p_{3/2} neutrons were measured. The cross sections, interpreted within the distorted-wave impulse approximation reaction framework, are consistent with a shell closure at the neutron number N=32, found as strong as at N=28 and N=34 in Ca isotopes from the same observables. The analysis of the momentum distributions leads to a difference of the root-mean-square radii of the neutron 1f_{7/2} and 2p_{3/2} orbitals of 0.61(23) fm, in agreement with the modified-shell-model prediction of 0.7 fm suggesting that the large root-mean-square radius of the 2p_{3/2} orbital in neutron-rich Ca isotopes is responsible for the unexpected linear increase of the charge radius with the neutron number.

Ameliorating effect of Trigonella foenum-graecum L. (fenugreek) extract tablet on exhaustive exercise-induced fatigue in rats by suppressing mitophagy in skeletal muscle

OBJECTIVE

Trigonella foenum-graecum L. (fenugreek) is widely used as a leafy vegetable and spice in China and North Africa. Recent studies have reported that fenugreek can reduce fatigue; however, its antifatigue mechanism remains unclear. Therefore, this study aimed to investigate the potential antifatigue effects of fenugreek extract (FE) on mitophagy and the underlying mechanisms.

MATERIALS AND METHODS

We evaluated the potential effects of FE tablet on an exhaustive exercise-induced fatigue (EEF) rat model. Oxidative stress indicators and fatigue biomarkers in the serum and skeletal muscle were detected. Mitophagy and mitochondrial morphology were observed using transmission electron microscopy. The expression levels of mitochondrial autophagy-related proteins were detected using western blot and immunofluorescence.

RESULTS

Compared with the model group, FE enhanced the activities of the antioxidant enzymes superoxide dismutase and glutathione peroxidase as well as total antioxidant capacity; however, it decreased the level of malondialdehyde in the serum and skeletal muscle after a 7-day treatment. Moreover, certain indicators of mitochondrial function, such as reactive oxygen species levels, ATP levels, cellular and mitochondrial Ca2+ levels, and ATPase activity, were significantly improved in the FE group compared with the model group. Finally, we found that mitophagy was induced by exhaustive exercise and inhibited by FE. Regarding mitochondrial autophagy-related proteins, the expression levels of LC3B, FUNDC1, PGAM5, PARKIN, and PINK1 in the skeletal muscle tissue were increased in the EEF group compared with the control group. After administration of FE and a positive control drug, a significant reversal in the expression of the above-mentioned proteins was noted.

CONCLUSIONS

Our findings demonstrate that FE exerted antifatigue effects in the EEF rat model by regulating the mitophagy-related FUNDC1/LC3B signaling pathway rather than the PINK1/PARKIN signaling pathway.

NOMOGRAM COMBINING PREOPERATIVE ULTRASONOGRAPHY WITH CLINICAL FEATURES FOR PREDICTING LYMPH NODES POSTERIOR TO THE RIGHT RECURRENT LARYNGEAL NERVE METASTASIS IN PATIENTS WITH PAPILLARY THYROID CANCER

Aim

To establish a nomogram combining preoperative ultrasonic and clinical features for predicting lymph nodes posterior to the right recurrent laryngeal nerve (LN-prRLN) metastasis in papillary thyroid carcinoma (PTC) patients.

Methods

Preoperative ultrasonic and clinical variables of patients with PTC from 2014 to 2021 were retrospectively analyzed. The risk factors associated with LN-prRLN metastasis were identified and validated through a developed nomogram model based on univariate and multivariate logistic regression analysis.

Results

A total of 615 patients (690 lesions) were enrolled for the training dataset and 207 patients (226 lesions) for the validation dataset with 54 (6.57%) patients developing LN-prRLN metastasis. Multivariate logistic regression analysis demonstrated that the preoperative ultrasound measurement of larger tumors (≥20 mm), higher TI-RADS category (category 5), and higher thyroglobulin level (9.86 ng/mL) in patients with PTC were predictive factors for LN-prRLN metastasis. The nomogram model was established and verified yielding a relatively good predictive performance in the training and validation dataset (AUC: 0.868 vs. 0.851).

Conclusions

The nomogram combining preoperative ultrasonography with clinical features in this study is highly predictive of LN-prRLN metastasis in patients with PTC, which may provide more personalized recommendations for clinicians in preoperative decision-making for complete dissection of LN-prRLN.

[Risk factors of residual tumor in single small hepatocellular carcinoma after thermal ablation treatment]

Objective: To evaluate the risk factors of residual tumor after thermal ablation in patients with small hepatocellular carcinoma. Methods: This was a retrospective study recruiting 107 patients diagnosed as single hepatocellular carcinoma with maximum diameter ≤3 cm from December 2009 to August 2015 in National Cancer Center. The cohort enrolled 81 males and 26 females, including 83 patients younger than 70 years old. All patients were treated with radiofrequency ablation or microwave ablation, and evaluated by CT or MRI after 4-6 weeks compared with baseline data. Potentially related factors were analyzed such as patients' characteristics, tumor location and adjacent, ablation pattern, hepatitis B/C infection. A multivariate logistic regression analysis was conducted for the independence of risk factors. Results: Six patients (5.6%) with residual tumor was detected in the whole population of 101 cases. Univariate analysis suggested that tumor adjacent to vascular structure, poor differentiation, AFP≥200 μg/L were the risk factors of residue disease (all P<0.05). Multivariate logistic regression suggested that pathological type of poorly differentiated tumor was the only independent risk factor (HR=2.26,95%CI 0.25-20.50, P=0.030). Conclusions: Poorly differentiated pathology is an independent predictive factor for residual disease in small hepatocellular carcinoma after thermal ablation. Such patients should be routinely followed up after operation.

The molecular basis of spinocerebellar ataxia type 48 caused by a de novo mutation in the ubiquitin ligase CHIP

The spinocerebellar ataxias (SCAs) are a class of incurable diseases characterized by degeneration of the cerebellum that results in movement disorder. Recently, a new heritable form of SCA, spinocerebellar ataxia type 48 (SCA48), was attributed to dominant mutations in STIP1 homology and U box-containing 1 (STUB1); however, little is known about how these mutations cause SCA48. STUB1 encodes for the protein C terminus of Hsc70 interacting protein (CHIP), an E3 ubiquitin ligase. CHIP is known to regulate proteostasis by recruiting chaperones via a N-terminal tetratricopeptide repeat domain and recruiting E2 ubiquitin-conjugating enzymes via a C-terminal U-box domain. These interactions allow CHIP to mediate the ubiquitination of chaperone-bound, misfolded proteins to promote their degradation via the proteasome. Here we have identified a novel, de novo mutation in STUB1 in a patient with SCA48 encoding for an A52G point mutation in the tetratricopeptide repeat domain of CHIP. Utilizing an array of biophysical, biochemical, and cellular assays, we demonstrate that the CHIPA52G point mutant retains E3-ligase activity but has decreased affinity for chaperones. We further show that this mutant decreases cellular fitness in response to certain cellular stressors and induces neurodegeneration in a transgenic Caenorhabditis elegans model of SCA48. Together, our data identify the A52G mutant as a cause of SCA48 and provide molecular insight into how mutations in STUB1 cause SCA48.

Spiro-Oxindole Skeleton Compounds Are Efficient Inhibitors for Indoleamine 2,3-Dioxygenase 1: An Attractive Target for Tumor Immunotherapy

Indoleamine 2,3-dioxygenase 1 (IDO1) is an attractive heme enzyme for its significant function in cancer immunotherapy. Potent IDO1 inhibitors have been discovered for decades, whereas no clinical drugs are used for cancer treatment up to now. With the goal of developing medically valuable IDO inhibitors, we performed a systematic study of SAR405838 analogs with a spiro-oxindole skeleton in this study. Based on the expression and purification of human IDO1, the inhibitory activity of spiro-oxindole skeleton compounds to IDO1 was evaluated by IC50 and Ki values. The results demonstrated that inhibitor 3 exhibited the highest IDO1 inhibitory activity with IC50 at 7.9 μM among all inhibitors, which is ~six-fold of the positive control (4-PI). Moreover, inhibitor 3 was found to have the most effective inhibition of IDO1 in MCF-7 cancer cells without toxic effects. Molecular docking analysis revealed that the hydrophobic interaction stabilized the binding of inhibitor 3 to the IDO1 active site and made an explanation for the uncompetitive mode of inhibitors. Therefore, this study provides valuable insights into the screen of more potent IDO1 inhibitors for cancer immunotherapy.

Intra-couple discordance in preconception syphilis screening for both spouses: a national and population-based survey in China, 2013-2018

OBJECTIVE

The antenatal screening strategy remains inadequate for eliminating congenital syphilis. To further eliminate maternal fetal transmission, preconception syphilis screening is considered an option. In this study, we investigated syphilis seropositivity and intra-couple discordance among married couples planning a pregnancy in China to provide essential baseline evidence for preconception syphilis screening.

DESIGN

Population-based survey.

SETTING

National preconception registered data.

POPULATION

Married Chinese couples planning conception within 6 months between 2013 and 2018.

METHODS

Syphilis was screened using rapid plasma reagin (RPR); infection self-reporting and sociodemographic characteristics were collected through questionnaires and medical records, respectively. r 3.2.2 and arcgis 10.2 were used for statistical analyses and geographic mapping.

MAIN OUTCOME MEASURES

RPR seropositivity.

RESULTS

Among 31 955 041 couples, 29 737 172 (93.06%) had complete RPR results for both spouses; of those, 0.62% (186 100) were seropositive, with dramatic intra-couple discordance, with 0.33% positivity in wives, 0.24% positivity in husbands and 0.05% positivity in both spouses. Across time, both seropositivity and intra-couple discordance remained stable. Seropositivity in different regions varied significantly, with provincial rates ranging geographically from Tibet (0.8%) to Hebei (0.2%) (P < 0.05). Economic level was an independent factor for this regional variation, with seropositivity increasing as gross domestic product income decreased (P < 0.05).

CONCLUSIONS

Intra-couple discordance in seropositivity for syphilis is notable among couples, with a considerable rate of pre-existing syphilis before pregnancy. Thus, screening both spouses during integrated preconception health care is recommended for further eliminating maternal-fetal transmission.

TWEETABLE ABSTRACT

Intra-couple discordance in seropositivity for syphilis is notable among couples, with a considerable rate of pre-existing syphilis before pregnancy. Screening both spouses during integrated preconception health care is recommended to further eliminate maternal-fetal transmission.

The association between the vaginal microenvironment and fecundability: a register-based cohort study among Chinese women

OBJECTIVE

To evaluate the association between the vaginal microenvironment and fecundability among women.

DESIGN

Register-based nationwide cohort study.

SETTING

Chinese National Free Pre-conception Check-up Project from 2015 to 2018.

POPULATION

Our study included a total of 3 388 554 eligible women who were attempting to become pregnant.

METHOD

We assessed the vaginal microenvironment at baseline by considering four indices: vaginal pH, clue cell examination, whiff test and vaginal cleanliness grading. If any of these indicators was abnormal, the vaginal microenvironment was defined as poor. Propensity score matching was used to control for potential confounders and reduce bias. Logistic models were used to estimate the fecundability odds ratios (FORs) after adjustment for covariates.

MAIN OUTCOME MEASURES

Achievement of a pregnancy within 1 year.

RESULTS

Of the total study population, 379 718 women (11.2%) had a poor vaginal microenvironment and their pregnancy rate after 1 year was significantly lower than the group with a normal microenvironment (71.8% versus 76.1%, P < 0.001). After adjusting for potential confounders, the women with a poor vaginal microenvironment were associated with a 9% reduction in fecundability compared with the normal microenvironment group (FOR 0.91, 95% CI 0.90-0.92). The adverse effects of a poor vaginal microenvironment were stronger among multipara (FOR 0.89, 95% CI 0.87-0.90) or women with irregular menstruation (FOR 0.86, 95% CI 0.84-0.89).

CONCLUSION

There was a negative association between a poor vaginal microenvironment and the fecundability of women. These findings highlight the significance of assessing the vaginal microenvironment during pre-pregnancy health examinations.

TWEETABLE ABSTRACT

Women with a poor vaginal microenvironment were associated with a reduction in fecundability.

Pairing Forces Govern Population of Doubly Magic ^{54}Ca from Direct Reactions

Direct proton-knockout reactions of ^{55}Sc at ∼220  MeV/nucleon were studied at the RIKEN Radioactive Isotope Beam Factory. Populated states of ^{54}Ca were investigated through γ-ray and invariant-mass spectroscopy. Level energies were calculated from the nuclear shell model employing a phenomenological internucleon interaction. Theoretical cross sections to states were calculated from distorted-wave impulse approximation estimates multiplied by the shell model spectroscopic factors, which describe the wave function overlap of the ^{55}Sc ground state with states in ^{54}Ca. Despite the calculations showing a significant amplitude of excited neutron configurations in the ground-state of ^{55}Sc, valence proton removals populated predominantly the ground state of ^{54}Ca. This counterintuitive result is attributed to pairing effects leading to a dominance of the ground-state spectroscopic factor. Owing to the ubiquity of the pairing interaction, this argument should be generally applicable to direct knockout reactions from odd-even to even-even nuclei.

Inhibitory investigation of niacin derivatives on metalloenzyme indoleamine 2,3-dioxygenase 1 for its immunomodulatory function

Inhibitors of indoleamine 2,3-dioxygenase 1 (IDO1) have received wide attention for their roles in cancer immunotherapy. It highlights the important role of metalloenzymes in performing human physiological functions. Herein, the recombinant human IDO1 was expressed and purified successfully, and the protein molecule was characterized by SDS-PAGE, MALDI-TOF mass spectrometry, and metalloenzymology. A series of niacin derivatives were investigated with regard to their inhibition on metalloenzyme IDO1, and the resulting potential anti-cancer activities in cell lines. Among the niacin derivatives, 4,4,4-trifluoro-1-(pyridin-3-yl)-butane-1,3-dione (compound 9) was found to be the most effective inhibitor to IDO1 in HepG-2 cells, with an EC50 of 11 µM with low cytotoxicity. The IC50 value of compound 9 with trifluoroethyl group in enzymatic inhibition was shown to be ∼5 times more potent than a positive control 4-phenylimidazole. The interaction between compound 9 and IDO1 was verified by isothermal titration calorimetry and molecular docking study. The most favorable molecular docking results revealed that functional groups of compound 9 contributed to the binding of 9 to IDO1 through IDO1-heme coordination, H-bond interactions and hydrophobic contacts. Our finding provides a strategy for the development of new inhibitor candidates for the therapeutic inhibition of IDO1.

Long non-coding RNA AK027294 promotes tumor growth by upregulating PCNA in gastric cancer

OBJECTIVE

Recent researches have proved that long non-coding RNAs (lncRNAs) has an important role in many diseases. In this research, lncRNA AK027294 was explored to identify how it functions in the development of gastric cancer (GC).

PATIENTS AND METHODS

Real Time-quantitative-Polymerase Chain Reaction (RT-qPCR) was utilized to detect AK027294 expression in GC patients. Then, MTT assay, colony formation assay, and EdU incorporation assay were performed to identify its function in GC cells. Furthermore, the potential mechanism was also explored using mechanism assays.

RESULTS

AK027294 expression level was significantly higher in GC tissue samples and cell lines. Results of MTT assay, colony formation assay, and EdU incorporation assay showed that cell proliferation was inhibited through the silence of AK027294 in GC cells, while cell proliferation was promoted through overexpression of AK027294 in GC cells. Furthermore, the expression of PCNA was downregulated via silence of AK027294 in GC cells, while the expression of PCNA was upregulated via overexpression of AK027294 in GC cells. The correlation analysis showed that PCNA expression was positively correlated with AK027294 expression in GC tissues.

CONCLUSIONS

Our results suggest that AK027294 could enhance cell proliferation of GC cells by upregulating PCNA and might be applied as a novel target for therapy of GC.

Isolation and characterization of endophytic bacteria for controlling root rot disease of Chinese jujube

AIM

Fusarium oxysporum is the primary pathogen causing root rot disease that severely affects cultivation of jujube fruit in the Xinjiang province of China. The aim of this study was to identify endophytic bacteria in healthy jujube organs that could effectively suppress F. oxysporum growth.

METHODS AND RESULTS

Different plant organs (leaves, twigs and roots) were collected from healthy Chinese jujube cultivated in southern Xinjiang province of China. The endophytic bacterium Brevibacterium halotolerans JZ7 was selected for its strong antagonistic activity and growth-promoting characteristics. Gas-chromatography mass-spectrometry analysis showed that acetoin, 2,3-butanediol and fenretinide were the three dominant volatile organic compounds produced by strain JZ7. Fenretinide strongly suppressed spore germination of F. oxysporum in vitro. Pot experiments showed that strain JZ7 colonized both the roots and rhizosphere soil of Chinese jujube and significantly reduced F. oxysporum level in jujube rhizosphere soil.

CONCLUSION

We demonstrated that B. halotolerans JZ7 can be developed into a biological control agent to combat root rot disease of Chinese jujube in the Xinjiang province of China.

SIGNIFICANCE AND IMPACT OF THE STUDY

The suggested strategy for biological control of jujube root rot disease is fully in accordance with the current principles of sustainability.

MiR-630 inhibits papillary thyroid carcinoma cell growth, metastasis, and epithelial-mesenchymal transition by suppressing JAK2/STAT3 signaling pathway

OBJECTIVE

Evidence has demonstrated that miR-630 is involved in multiple processes in cancer development and progression. However, the exact functions of miR-630 in papillary thyroid carcinoma (PTC) and the underlying mechanisms remain undefined. Therefore, the aims of the present study were to investigate the role and potential mechanism of miR-630 in tumorigenicity of PTC.

PATIENTS AND METHODS

Microarrays were used to analyze the differentially expressed miRNAs in PTC tissues. Expression of miR-630 in PTC tissues and cell lines were determined by a qRT-PCR assay. CCK-8 assays, clonogenic survival assays, cell apoptosis analysis, wound healing assays and transwell invasion assays were used to examine the tumorigenesis function of miR-630 in vitro. Protein expression of signaling pathways was determined by using Western blot.

RESULTS

We found that miR-630 was significantly downregulated in PTC tissues and cell lines. Overexpression of miR-630 inhibited PTC cell proliferation and induced cell apoptosis via suppressing the expression of caspase-3 and caspase-6. In addition, up-regulation of miR-630 suppressed the migration and invasion in PTC cells by suppressing EMT progress. Mechanistic investigations showed forced miR-660 expression decreased proteins expression of phosphorylation levels in JAK2/STAT3 signaling.

CONCLUSIONS

We firstly provided the evidence that miR-630 displayed a tumor-promotive role in PTC progression through modulating JAK2/STAT3 pathway, and that a potential therapeutic strategy through enhancing miR-630 expression might benefit PTC patients.

CTXA hip: the effect of partial volume correction on volumetric bone mineral density data for cortical and trabecular bone

This study compares the results of computed tomography X-ray absorptiometry (CTXA) hip volumetric BMD (vBMD) analyses of cortical and trabecular bone with and without partial volume correction. For cortical bone in some circumstances, corrected cortical volumes were negative and corrected vBMD was very high. For trabecular bone, the correction effects are smaller. CTXA volumetric data should be interpreted with caution.

PURPOSE

Previous studies have reported concerns about the reliability of CTXA hip cortical vBMD measurements generated using partial volume (PV) correction (the "default" analysis, with cortical PV correction). To date, no studies have examined the results of the alternative ("new") analysis (with trabecular PV correction). This study presents in vivo and phantom data comparing the corrected and uncorrected data for cortical and trabecular bone respectively.

METHODS

We used the commercial QCTPro CTXA software to analyze CT scans of 129 elderly Chinese men and women and an anthropomorphic European Proximal Femur phantom (EPFP) and accessed data for two alternative scan analyses using the database dump utility. The CTXA software gives the user two methods of performing the PV correction: (1) a default analysis in which only cortical bone results are corrected; (2) a new analysis in which only trabecular bone results are corrected. Both methods are based on a numerical recalculation of vBMD values without any change in volume of interest (VOI) placement.

RESULT

In vivo, the results of the two analyses for integral bone were the same while cortical and trabecular results were different. PV correction of cortical bone led to a decrease of cortical volume for all four VOIs: total hip (TH), femoral neck (FN), trochanter (TR), and intertrochanter (IT) volumes were reduced on average by 7.8 cm³, 0.9 cm³, 2.5 cm³, and 4.3 cm³ respectively. For TR, where cortex was thinnest, average corrected cortical volume was negative (- 0.4± 1.3 cm³). Corrected cortical vBMD values were much larger than uncorrected ones for TH, FN, and IT. Scatter plots of corrected cortical vBMD against cortical bone thickness showed that elevated results correlated with thinner cortices. When trabecular bone was corrected for the PV effect, trabecular volumes of TH, FN, TR, and IT were reduced on average by 7.9 cm³, 0.8 cm³, 2.6 cm³, and 4.4 cm³ respectively, while vBMD measurements were increased correspondingly. The trabecular volume and vBMD measurements of the two datasets both had highly positive correlations. For the EPFP, the PV-corrected FN data deviated from the nominal phantom value, but was closer for the TR and IT VOIs. Both corrected and uncorrected data overestimated trabecular vBMD, with the corrected results showing greater deviation from nominal values.

CONCLUSION

The default and new CTXA analyses for volumetric data generate different results, both for cortical and trabecular bone. For cortical bone, the uncorrected results are subject to partial volume effects but the correction method of the default analysis overcorrects the effect leading to in part unreasonable results for cortical bone volume and BMD. For trabecular bone, the correction effects are smaller. CTXA volumetric data should be interpreted with caution.