Small animal PET imaging with the 68Ga-labeled pH (low) insertion peptide-like peptide YJL-4 in a triple-negative breast cancer mouse model

BACKGROUND

The aim of this study was to prepare a novel 68Ga-labeled pH (low) insertion peptide (pHLIP)-like peptide, YJL-4, and determine its value for the early diagnosis of triple-negative breast cancer (TNBC) via in vivo imaging of tumor-bearing nude mice. The novel peptide YJL-4 was designed using a template-assisted method and synthesized by solid-phase peptide synthesis. After modification with the chelator 1,4,7‑triazacyclononane-N,N',N″-triacetic acid (NOTA), the peptide was labeled with 68Ga. Then, the biodistribution of 68Ga-YJL-4 in tumor-bearing nude mice was investigated, and the mice were imaged by small animal positron emission tomography (PET).

RESULTS

The radiochemical yield and radiochemical purity of 68Ga-YJL-4 were 89.5 ± 0.16% and 97.95 ± 0.06%, respectively. The biodistribution of 68Ga-YJL-4 in tumors (5.94 ± 1.27% ID/g, 6.72 ± 1.69% ID/g and 4.54 ± 0.58% ID/g at 1, 2 and 4 h after injection, respectively) was significantly greater than that of the control peptide in tumors at the corresponding time points (P < 0.01). Of the measured off-target organs, 68Ga-YJL-4 was highly distributed in the liver and blood. The small animal PET imaging results were consistent with the biodistribution results. The tumors were visualized by PET at 2 and 4 h after the injection of 68Ga-YJL-4. No tumors were observed in the control group.

CONCLUSIONS

The novel pHLIP family peptide YJL-4 can adopt an α-helical structure for easy insertion into the cell membrane in an acidic environment. 68Ga-YJL-4 was produced in high radiochemical yield with good stability and can target TNBC tissue. Moreover, the strong concentration of radioactive 68Ga-YJL-4 in the abdomen does not hinder the imaging of early TNBC.

Ipsilateral and contralateral patent processus vaginalis in pediatric patients with a unilateral nonpalpable testis

This study aimed to investigate the incidence of patent processus vaginalis (PPV) in pediatric patients with a unilateral nonpalpable testis and explore the associated factors. From May 2014 to April 2017, 152 boys who were diagnosed with a unilateral nonpalpable testis and underwent laparoscopy in Shanghai Children's Hospital (Shanghai, China) were included in this study. The data were collected and reviewed, and the results were analyzed regarding the age at operation, side, development, and position of the nonpalpable testis. The mean age of the patients was 2.6 (standard deviation: 2.3) years. The testis was absent in 14 cases, nonviable in 81 cases, and viable in 57 cases. The incidence of PPV was 37.5% (57 of 152) on the ipsilateral side and 16.4% (25 of 152) on the contralateral side. The ipsilateral PPV was more prevalent when the nonpalpable testis occurred on the right side ( P < 0.01). Besides, patients with a viable testis had a greater incidence of ipsilateral PPV than those with a nonviable or absent testis ( P < 0.01). Moreover, this rate was the highest when the testis was in the abdominal cavity and the lowest when the testis was in the scrotum (both P < 0.01). However, the incidence of contralateral PPV was independent of all the factors. In conclusion, in children with a nonpalpable testis, the incidence of an ipsilateral PPV was significantly related to the side, development, and position of the testis, while it was independent of these factors on the contralateral side.

KRAS mutation status between left- and right-sided colorectal cancer: are there any differences in computed tomography?

PURPOSE

To investigate the differences in clinicopathological and imaging features according to KRAS mutation status in left- and right-sided colorectal cancer.

METHOD

A total of 157 patients with pathologically proven colorectal cancer and preoperative contrast-enhanced multidetector CT examinations were enrolled. According to the tumor location and KRAS status, they were divided into two groups: the left-sided colorectal cancer (LCC) group (wild type, mutant type) and the right-sided colorectal cancer (RCC) group (wild type, mutant type). Clinicopathological and imaging features were recorded in each group. The imaging observation indicators included short axis diameter (SAD), longitudinal tumor length (LTL), tumor shape, pericolic fat stranding, bowel stenosis, intratumoral low-density range, enhancement pattern, and bowel obstruction. Univariate and multivariate logistic regression analyses were performed to compare the difference in KRAS mutation status between groups.

RESULTS

In the LCC group, SAD, tumor shape, degree of pericolic fat stranding, and bowel obstruction were significant indicators for predicting KRAS status (P < 0.05). In the RCC group, CA19-9, SAD, and intratumoral low-density range were significant indicators for predicting KRAS status (P < 0.05.). The area under the curve (AUC) of the combination image indicators in the LCC group was 0.802 [cutoff point 0.372, 95% confidence interval (CI) 0.718-0.888, sensitivity 85.4%, specificity 72.0%]. The AUC in the RCC group was 0.828 (cutoff point 0.647, 95% CI 0.726-0.931, sensitivity 79.5%, specificity 75.0%).

CONCLUSION

The CT imaging features associated with KRAS mutation status in the LCC and RCC groups were different. The combination of tumor location and imaging features can help to further improve the predictive value of KRAS status.

Vacancy engineering of two-dimensional W2N3 nanosheets for efficient CO2 hydrogenation

Peaking carbon emissions and achieving carbon neutrality have become the consensus goal of the international community to solve the environmental problems threatening mankind caused by accumulative greenhouse gases like CO₂. Herein we proposed vacancy engineering of two-dimensional (2D) topological W₂N₃ for efficient CO₂ hydrogenation into high value-added chemicals and fuels. Spherical aberration corrected scanning transmission electron microscopy (Cs-corrected STEM) confirmed a large amount of N vacancies on the catalyst surface, which significantly reduced the energy barrier for the formation of the essential intermediates of *CO and *CHO as revealed by density functional theory (DFT) calculations. Consequently, the highly stable catalyst exhibited efficient CO₂ hydrogenation superior to many previous reports with a maximum CO₂ conversion rate of 24% and a high selectivity of 23% for C₂₊ hydrocarbons. This work provided not only insight into the vacancy-controlled CO₂ hydrogenation mechanism, but also fresh ammunition to bring the remaining potential of 2D topological transition metal nitrides in the field of catalysis.

Asymptomatic chronic suppurative cholecystitis and peritonitis mimicking metastasis by 18F-FDG PET/CT scan during sigmoid colon cancer surveillance

The study describes an unusual case that a patient with previous history of adenocarcinoma of sigmoid colon who has developed chronic suppurative cholecystitis and peritonitis was misdiagnosed as metastasis. This case is presented to illustrate the importance of considering benign etiologies that may mimic metastatic disease when interpreting positron emmision tomography (PET)/CT scans.

Synthesis and Evaluation of Radioiodine-Labeled pH (Low) Insertion Peptide Variant 7-Like Peptide as a Noninvasive Tumor Microenvironment Imaging Agent in a Mouse MDA-MB-231 Triple-Negative Breast Cancer Model

PURPOSE

The pH (low) insertion peptide (pHLIP) family can target the tumor microenvironment (TME). If pHLIP can be labeled with radioiodine, the imaging and treatment of tumors can be considered. However, tyrosine and tryptophan can bind with iodine in the insertion region of pHLIP, and radioiodine labeling may affect the formation of α-helix structures in acidic environments; therefore, it is necessary to adjust the structure of pHLIP. This study aims to develop an ¹²⁵I-labeled pH (low) insertion peptide variant 7-like peptide (pHLIP (Var7) LP) for imaging the TME in MDA-MB-231 triple-negative breast cancer (TNBC) xenograft tumor models.

PROCEDURES

Based on pHLIP (Var7), a new peptide sequence, pHLIP (Var7) LP, was obtained by the sequence modification method and then characterized. The binding of pHLIP (Var7) LP to MDA-MB-231 cells was analyzed. pHLIP (Var7) LP was labeled with ¹²⁵I by the iodogen iodination method. Serial biodistribution studies and small-animal single photon emission computed tomography (SPECT)/computed tomography (CT) imaging in subcutaneous MDA-MB-231 TNBC-bearing mice were performed using [¹²⁵I] I-pHLIP (Var7) LP.

RESULTS

A novel peptide, pHLIP (Var7) LP, has the characteristics of an α-helix structure, electronegativity, and amphiphilicity. Circular dichroism (CD) spectroscopy showed that the peptide presented a typical pH-dependent transition from an unstructured conformation to an α-helix structure when the pH was reduced from 8.0 to 4.0. The relative fluorescence intensities of 5-carboxytetramethylrhodamine (5-TAMRA)-pHLIP(var7) LP at pH = 6.0, 6.6, and 7.4 were 100.00 ± 5.98%, 72.10 ± 4.65%, and 13.72 ± 1.41%, respectively. The distribution of [¹²⁵I] I-pHLIP (Var7) LP in tumors reached the highest level (8.7 ± 1.6% ID/g) at 2 h after injection, and the tumor-to-muscle ratios and tumor-to-blood ratios increased with time. Of the measured off-target organs, the stomach, kidney, and bladder showed higher uptake levels. SPECT imaging revealed rapid and sustained tumor uptake of [¹²⁵I] I-pHLIP (Var7) LP in breast cancer-bearing mice.

CONCLUSIONS

This study showed that [¹²⁵I]I-pHLIP (Var7)LP had rapid and sustained tumor uptake in MDA-MB-231 TNBC and provided a new method for TNBC imaging and further treatment.

A Redox-Activatable DNA Nanodevice for Spatially-Selective, AND-Gated Imaging of ATP and Glutathione in Mitochondria

Design of biosensors capable of imaging ATP and glutathione (GSH) in mitochondria remains a challenge, despite their importance in elucidating their correlated pathophysiological events. Here, we report a new strategy that uses redox-activatable aptamer sensor design combined with nanoparticle-based targeting capability to achieve spatially controlled, AND-gated imaging of ATP and GSH in mitochondria. The DNA nanodevice was designed by the controlled assembly of the redox-responsive ATP aptamer probe on the nanoparticles and further decorated with mitochondria-targeting signals. We demonstrate that the system allows for mitochondria-specific, correlated imaging of ATP and GSH in living cells and in vivo. Furthermore, because the system can be lighted up only when meeting the "dual keys" (overexpressed ATP and GSH in mitochondria) simultaneously, the DNA nanodevice enables specific imaging of tumors in vivo with improved tumor-to-normal tissue ratio. This work illustrates the potential of the DNA nanodevices in the imaging of mitochondrial multivariate targets.

Can a radioimmunoassay kit be developed for accurate detection of the S protein of severe acute respiratory syndrome coronavirus 2?

The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) at the end of 2019 spread worldwide within only a few months. The screening and timely isolation of infected individuals have been regarded as an effective means of epidemic prevention and control. Therefore, effective screening of infected individuals plays a vital role in epidemic prevention and control. At present, reverse transcription-polymerase chain reaction (RT–PCR) is the main method for the in vitro detection of SARS-CoV-2. However, RT–PCR requires certified laboratories, expensive equipment, and trained technicians. Therefore, it is necessary to develop simpler and more convenient methods. Some studies have shown that the PepKAA peptide has a high affinity for the S protein of SARS-CoV-2. The tyrosine in PepKAA is labeled with ¹²⁵I and used to design a radioimmunoassay kit for the detection of the S protein of SARS-CoV-2, which is of great significance for the early diagnosis of COVID-19.

Health-Related Quality of Life in Predominantly Young Parental Living Liver Donors: A Cross-Sectional Study in China

Objective: The health-related quality of life (HRQoL) of donors deserves attention and must be considered for a long time. Many of the published studies had small sample sizes, and research from mainland China, in particular, is scant. Thus, this study aimed to investigate the HRQoL of living liver donors and identify the influencing factors of the HRQoL in mainland China.

Methods: This is a cross-sectional study. The data were collected from the liver transplantation center, the Tianjin First Center Hospital, China. Living liver donors older than 18 years and at a minimum of 1-month, post-donation was included. The HRQoL was evaluated using the Medical Outcome Study Short form 36 (SF-36). Sociodemographic and clinical-related variables, HRQoL status, and its potential impact factors were analyzed.

Results: A total of 382 living liver donors completed the survey. The median number of months post-donation was 25, and parental donors (99.2%) were the most frequent relationship. The majority of the participants (372, 97.4%) donated their left lateral lobes. Thirty-two (8.4%) donors suffered complications, and of them, 7 suffered from biliary leakage (1.8%), which was the most common one in this study. The physical functioning (PF), role–physical (RP), bodily pain (BP), general health (GH), social functioning (SF), role–emotional (RE), and mental health (MH) scores among the living liver donors were significantly better than those of the Chinese norms. Short-time post-donation [odds ratio (OR): 0.008; p < 0.001] and male recipients (OR:0.195; p = 0.024) were associated with the likelihood of a poor physical related quality of life.

Conclusions: Despite, in general, good HRQoL outcomes, we also believed that liver donation has an obvious influence on the physical functions of liver donors. More attention and long-term follow-ups are necessary for donors at higher risk based on identified influencing factors and correlates.

Efficacy of Adherence-Enhancing Interventions for Immunosuppressive Therapy in Solid Organ Transplant Recipients: A Systematic Review and Meta-Analysis Based on Randomized Controlled Trials

Background

Immunosuppressant non-adherence is a widespread problem among solid organ recipients. With the newly published clinical trials, the randomized controlled trials (RCTs) based systematic review of adherence-enhancing interventions on immunosuppressant adherence in solid organ recipients has not been completed. In this systematic review and meta-analysis, we compared the efficacy of adherence-enhancing interventions versus routine intervention, as performed with RCTs, on immunosuppressant adherence in solid organ transplantation recipients.

Methods

PubMed, Embase, Cochrane Library, CINAHL full text, and PsycINFO were searched from database inception to December 2019. This review was conducted following the PRISMA’s reporting guidelines and according to the principles recommended by Cochrane Handbook for Systematic Review.

Results

The search yielded 10,479 articles. A total of 27 articles (26 studies) with 715 participants were included in our analysis. Results from the meta-analysis revealed that as compared with that of the routine intervention group, the rates of overall adherence, dosing adherence, and timing adherence were significantly increased within the adherence-enhancing intervention group, with the pooled risk ratio (RR) of overall adherence = 1.17, [95% confidence interval (CI): 1.07 to 1.28; p = 0.0006]; RR of dosing adherence = 1.21 (95% CI: 1.08 to 1.36, p = 0.001); RR of timing adherence = 1.16 (95% CI: 1.03 to 1.29, p = 0.01). There was a significantly increased adherence score in the adherence-enhancing intervention group; however, no statistical significance on the immunosuppressant blood concentration was found between the two study groups. Results obtained from a subgroup analysis shown interventions led by a multidisciplinary team, both the assessment time at 6 months and 12 months demonstrated a significantly increased adherence rate in the intervention group compared with the control group.

Conclusions

The findings of this report indicate that clinicians (doctors and nurses) should maintain a long-term intervention protocol to ensure immunosuppressant adherence within solid organ transplant recipients. To accomplish this goal, we recommend a multidisciplinary team-led, comprehensive intervention approach combined with mobile health monitoring for the administration of an effective immunosuppressive therapy regimen.

A model of malignant risk prediction for solitary pulmonary nodules on 18 F-FDG PET/CT: Building and estimating

BACKGROUND

To develop a model of malignant risk prediction of solitary pulmonary nodules (SPNs) using metabolic characteristics of lesions.

METHODS

A total of 362 patients who underwent PET/CT imaging from January 2013 to July 2017 were analyzed. Differences in the clinical and imaging characteristics were analyzed between patients with benign SPNs and those with malignant SPNs. Risk factors were screened by multivariate nonconditional logistic regression analysis. The self-verification of the model was performed by receiver operating characteristic (ROC) curve analysis, and out-of-group verification was performed by k-fold cross-validation.

RESULTS

There were statistically significant differences in age, maximum standardized uptake value (SUV_max ), size, lobulation, spiculation, pleural traction, vessel connection, calcification, presence of vacuoles, and emphysema between patients with benign nodules and those with malignant nodules (all P < 0.05). The risk factors for malignant nodules included age, SUV_max , size, lobulation, calcification and vacuoles. The logistic regression model was as follows: P = l/(1 + e^-x ), x = - 5.583 + 0.039 × age + 0.477 × SUV_max  + 0.139 × size + 1.537 × lobulation - 1.532 × calcification + 1.113 × vacuole. The estimated area under the curve (AUC) for the model was 0.915 (95% CI: 0.883-0.947), the sensitivity was 89.7%, and the specificity was 78.9%. K-fold cross-validation showed that the training accuracy was 0.899 ± 0.011, and the predictive accuracy was 0.873 ± 0.053.

CONCLUSIONS

The risk factors for malignant nodules included age, SUV_max , size, lobulation, calcification and vacuoles. After verification, the model has satisfactory accuracy, and it may assist clinics make appropriate treatment decisions.

pHLIP(Var7)-P1AP suppresses tumor cell proliferation in MDA-MB-231 triple-negative breast cancer by targeting protease activated receptor 1

PURPOSE

Protease-activated receptor 1 (PAR1) is a signaling protein ubiquitously present on the surface of tumor cells, and its homologous protein fragment, PAR1-activating peptide (P1AP), can inhibit protein signal transduction of PAR1/G in tumor cells. pH (Low) insertion peptide (pHLIP) can target the acidic tumor microenvironment (TME) and can be used as an excellent carrier to deliver P1AP to tumor cells for therapeutic purposes.

METHODS

PAR1 expression on the surface of MDA-MB-231 cells and human MCF10A mammary epithelial cells was observed. The binding between fluorescent-labeled pHLIP(Var7)-P1AP and MDA-MB-231 cells under different pH values was analyzed. The effect of pHLIP(Var7)-P1AP on the proliferation of MDA-MB-231 cells was analyzed under the conditions of pH 7.4 and 6.0.

RESULTS

PAR1 was highly expressed on the surface of MDA-MB-231 cells. In an acidic environment (pH 6.0 and 5.0), fluorescent-labeled pHLIP(Var7)-P1AP and MDA-MB-231 cells had a high binding ability, and the binding ability increased with the decrease in pH. In an acidic environment (pH 6.0), pHLIP(Var7)-P1AP significantly inhibited MDA-MB-231 cell proliferation. With 0.5 μg, 1 μg, 2 μg, 4 μg, and 8 μg of pHLIP(Var7)-P1AP, the cell proliferation inhibition rates were 3.39%, 5.27%, 14.29%, 22.14%, and 35.69%, respectively.

CONCLUSION

PAR1 was highly expressed on the surface of MDA-MB-231 cells. pHLIP(Var7)-P1AP can effectively target MDA-MB-231 cells in an acidic environment and inhibit the growth of MDA-MB-231 cells by inhibiting the signal transduction of PAR1/G protein.

Fluorodeoxyglucose-positron emission tomography/computed tomography imaging features of colloid adenocarcinoma of the lung: a case report

Background

Colloid adenocarcinoma of the lung is a rare subtype of variants of invasive adenocarcinomas. We report the appearance of this unusual entity on ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography.

Case presentation

A 60-year-old man of Chinese Han nationality coughed with a little white sputum for 1 month. Chest computed tomography showed multiple bilateral subpleural nodules and plaques accompanied by air bronchograms, which were most concentrated in the lower lobe of his right lung. Positron emission tomography indicated increased radioactivity uptake with a maximum standardized uptake value of 3.5. Positron emission tomography/computed tomography showed a soft tissue density lesion in his left adrenal gland with a maximum standardized uptake value of 4.1. The positron emission tomography/computed tomography appearance suggested a primary colloid adenocarcinoma in the lower lobe of his right lung accompanied by intrapulmonary and left adrenal gland metastases. The diagnostic rate of colloid adenocarcinoma can be increased by combining the anatomic and metabolic information of lesions.

Conclusions

The advantage of positron emission tomography/computed tomography in the diagnosis of colloid adenocarcinoma, as with other cancers, is the ability to locate extrapulmonary disease, facilitating clinical staging.

The predictive ability of liver function indexes on 18F-FDG uptake in the liver

AIM

The liver is an important reference organ for positron emission tomography/ computed tomography (PET-CT) examination using 18F-fluorodeoxyglucose (18F-FDG). However, 18F-FDG uptake by the liver is affected by many factors. We therefore investigated the effect of hepatic function on 18F-FDG uptake in the liver.

METHODS

A retrospective analysis of data on the hepatic function and the mean liver standardized up-take value (SUV) of 18F-FDG uptake in the liver during PET-CT examination of 500 (381 males, 119 females, aged 27-71) physical examinees.

RESULTS

The mean liver SUV was 1.88 ± 0.20. The correlation coefficient and partial correlation coefficient for age, the levels of conjugated bilirubin, globulin, AST and the mean liver SUV were statistically significant (r' = 0.119, -0.197, -0.089 and 0.151, all p < 0.05). Multiple linear regression analysis showed that age and the levels of conjugated bilirubin, globulin and aspartate amino-transferase (AST) were independent factors that influenced changes in the mean liver SUV (β = 0.008, -0.025, -0.151 and 0.005, all p < 0.05). The globulin level had the biggest predictive ability (β' = -0.151, p < 0.05).

CONCLUSIONS

The uptake of 18F-FDG in the liver was influenced by some liver function indexes. The levels of conjugated bilirubin, globulin and AST were independent factors for predicting changes in the uptake of 18F-FDG in the liver. Liver function test results should be combined with an evaluation of the metabolic activity of the liver.

[Predicting pharmacokinetics of anti-cancer drug, famitinib in human using physiologically based pharmacokinetic model]

This study is to establish physiologically based pharmacokinetic (PBPK) models of famitinib in rat and monkey, and then to predict the pharmacokinetics and tissue distribution of famitinib in human based on the PBPK models. According to published paper, previous studies and the chemical properties of famitinib predicted by ACD/ADME suite and SimCYP, the PBPK models of rat and monkey were established and optimized using GastroPlus. And then, the PBPK models were applied to predict the pharmacokinetic and tissue distribution of famitinib in human. The results showed that the PBPK models of rat and monkey can fit the observed data well, and the AUC0-∞, ratios of observed and calculated data in rat and monkey were 1.00 and 0.97, respectively. The AUC0-∞, ratios of observed and predicted data in human were 1.63 (rat to human) and 1.57 (monkey to human), respectively. The rat and monkey PBPK models of famitinib were well established, and the PBPK models were applied in predicting pharmacokinetic of famitinib in human successfully. Hence, the PBPK model of famitinib in human could be applied in future drug-drug interaction study.

[Chemical constituents of Euphorbia dracunculoides]

Sixteen compounds including daphnoretin (1), isofraxidin (2), scopoletin (3), kaempferol (4), quercetin (5), guaijaverin (6), astragalin (7), quercetin-3-O-β-D-glucopyranoside (8), naringenin-7-O-β-D-glucopyranoside (9), 5-O-methylapi- genin-7-O-β-D-glucopyranoside (10), methyl gallate (11), prionitiside A (12), (2S)-2,3-dihydroxypropyl-1,6,8-trihydroxy-3- methyl-9,10- dioxoanthracene-2-carboxylate (13), 3,3'-di-O-methyl ellagic acid (14), 3'-O-methyl-3,4-O,O-metheneellagic acid-4'-O-β-D- glucopyranoside (15) and 3,4-methylenedioxy-3'-O-methylellagic acid (16), were isolated from the 70% acetone extract of Euphorbia dracunculoides Lam. Among them, compounds 1-3, 6-9, 11, and 14 were isolated from E. dracunculoides for the first time, and compounds 10, 12, 13, 15, and 16 were firstly obtained from the genus Euphorbia. Their structures were elucidated by spectroscopic analysis, including 1H-NMR, 13C-NMR, and ESI-MS.

Inverse relationship between apolipoprotein A-I and cerebral white matter lesions: a cross-sectional study in middle-aged and elderly subjects

Background

Apolipoprotein A-I (apoA-I), the major protein for high density lipoprotein, is essential for reverse cholesterol transport. Decreased serum levels of apoA-I have been reported to correlate with subcortical infarction and dementia, both of which are highly related to white matter lesions (WMLs). However, the association between apoA-I and WMLs has never been investigated. In this study, we sought to investigate the association between apoA-I and the presence of WMLs in middle-aged and elderly subjects.

Methods

Consecutive patients aged 50 years and older of our department were prospectively enrolled in this study (n = 1282, 606 men and 676 women, 65.9±9.4 years). All participants underwent MRI scans to assess the presence and severity of WMLs. Multivariate logistic regression analyses were performed to examine the association of apoA-I with WMLs.

Results

Patients with WMLs were older and showed significantly higher proportion of male sex, hypertension, diabetes mellitus, previous stroke, and coronary heart disease whereas levels of total cholesterol, high density lipoprotein cholesterol, and apoA-I were lower. After adjustment for potential confounders, the lowest apoA-I quartile was independently associated with an increased risk of WMLs (odds ratio: 1.87, 95% confidence interval: 1.29–2.72). In sex-specific analyses, this relationship was observed only in women.

Conclusions

Our findings demonstrated that apoA-I was inversely associated with the presence of WMLs in middle-aged and elderly subjects. This results suggest that therapies which increase apoA-I concentration may be beneficial to reduce the risk of WMLs, dementia and stroke.

Use of Radioiodinated Peptide Arg-Arg-Leu Targeted to Neovasculari- zation as well as Tumor Cells in Molecular Tumor Imaging

OBJECTIVE

To explore a tumor peptide imaging agent Arginine-Arginine-Leucine (Tyr-Cys-Gly-Gly-Arg-Arg- Leu-Gly-Gly-Cys, tripeptide RRL [tRRL]) that targeted to tumor cells and tumor-derived endothelial cells (TDECs) and primarily investigate the possible relationship between tRRL and vascular endothelial growth factor receptor 2 (VEGFR-2).

METHODS

The tRRL sequence motif was identified as a tumor molecular marker specifically binding to TDECs. Tyrosine was conjugated to the amino terminal of RRL (Cys-Gly-Gly-Arg-Arg-Leu-Gly-Gly-Cys) for labeling with radionuclide iodine-131 ((131)I-tRRL). The uptake ability and molecular binding of tRRL to tumor cells and angiogenic endothelium were studied using flow cytometry and radioactivity counter in vitro. Whether VEGFR-2 is the binging site of tRRL was investigated. Biodistribution and single-photon emission computed tomography (SPECT) imaging of (131)I-tRRL were used to evaluate the effectiveness of this new imaging agent to visualize varied tumor xenografts in nude mice.

RESULTS

In vitro cellular uptake experiments revealed that tRRL could not only adhere to tumor angiogenic endothelial cells but also largely accumulate in malignant tumor cells. VEGFR-2, which is highly expressed on TDECs, was probably not the solely binding ligand for tRRL targeted to tumor angiogenic endothelium. (131)I-tRRL mainly accumulated in tumors in vivo, not other organs at 24 h after injection. SPECT imaging with (131)I-tRRL clearly visualized tumors in nude mice, especially at 24 h.

CONCLUSION

Radioiodinated tRRL offers a noninvasive nuclear imaging method for functional molecular imaging of tumors targeted to neovascularization, and may be a promising candidate for tumor radioimmunotherapeutic carrier.

Di-μ-chlorido-bis-[chlorido(N,N-di-methyl-ethylenediamine-κN,N')zinc(II)]

The centrosymmetric dinuclear title compound, [Zn(2)Cl(4)(C(4)H(12)N(2))(2)], is isostructural with its previously reported Cu(II) analogue [Phelps, Goodman & Hodgson (1976 ▶). Inorg. Chem.15, 2266-2270]. In the title compound, each of the Zn(II) ions is coordinated by two N atoms from a chelating N,N-dimethyl-ethylenediamine ligand, two bridging Cl atoms and one terminal Cl atom. The coordination environment is distorted square-pyramidal. The Zn-Cl bond distances of the two bridging Cl atoms are distinctly different: the equatorial Cl atom exbibits a Zn-Cl distance of 2.318 (1) Å and the axial Cl atom exbibits a Zn-Cl distance of 2.747 (2) Å, which is significantly longer. The mol-ecule can thus be seen as a dimer of two nearly square-planar monomeric units which are related to each other by an inversion center located in the middle of the dimer. Within one monomeric unit, the Zn atom, the two N atoms and the two Cl atoms are almost coplanar, with a mean deviation of only 0.05 (1) Å from the associated least-squares plane. The Zn⋯Zn distance within the dimer is 3.472 (3) Å. N-H⋯Cl and C-H⋯Cl hydrogen-bond inter-actions connect neighboring mol-ecules with each other.

(E)-2-[(2-Amino-4,5-dibromophenyl)iminomethyl]-6-methoxyphenol

The title compound, C₁₄H₁₂Br₂N₂O₂, was prepared from the condensation of 4,5-dibromo-1,2-phenyl­enediamine and 2-hydr­oxy-3-methoxy­benzaldehyde in methanol. The N=C double bond shows a trans conformation and the dihedral angle between the aromatic ring planes is 5.9 (4)°. In the crystal structure, there are intra­molecular O—H⋯N and N—H⋯N and inter­molecular N—H⋯O hydrogen bonds, the latter resulting in inversion dimers.

{6,6'-Dimeth-oxy-2,2'-[4-bromo-o-phenyl-enebis(nitrilo-methyl-idyne)]diphenolato}nickel(II) methanol solvate

In the title compound, [Ni(C₂₂H₁₇BrN₂O₄)]·CH₃OH, the Ni^II ion is in a slightly distorted square-planar geometry involving an N₂O₂ atom set of the tetra­dentate Schiff base ligand. The asymmetric unit contains one nickel complex and one methanol solvent mol­ecule. The dihedral angle between the aromatic ring planes of the central aromatic ring and other two aromatic rings are 10.8 (3) and 6.0 (2)°. The crystal structure is stabilized by inter­molecular C—H⋯O and C—H⋯Br and by intra­molecular O—H⋯O hydrogen bonds.

Diaqua-{6,6'-dimeth-oxy-2,2'-[ethane-1,2-diylbis(nitrilo-methyl-idyne)]diphenolato-κO,N,N',O'}manganese(III) perchlorate 18-crown-6 hemisolvate monohydrate

In the cation of the title compound, [Mn(C₁₈H₁₈N₂O₄)(H₂O)₂]ClO₄·0.5C₁₂H₂₄O₆·H₂O, the Mn^III ion is coordinated by two water O atoms, and two O atoms and two N atoms from the tetradentate 6,6′-dimeth­oxy-2,2′-[ethane-1,2-diylbis(nitrilo­methyl­idyne)]di­phenolate ligand, completing a distorted octa­hedral geometry. One O atom of the 18-crown-6-ether is disordered over two positions with occupancies of 0.70 (2) and 0.30 (2).

Tris(1,10-phenanthroline-κN,N')iron(II) μ-oxido-bis[trichloridoferrate(III)] ethanol hemisolvate

The title compound, [Fe(C(12)H(8)N(2))(3)][Fe(2)Cl(6)O]·0.5CH(3)CH(2)OH, consists of one [Fe(phen)(3)](2+) cation (phen = 1,10-phen-anthroline), one [Fe(2)Cl(6)O](2-) anion and one half-mol-ecule of ethanol. In the cation, the Fe(II) atom is coordinated by six N atoms from three phen ligands in a distorted octa-hedral geometry. In the bent anion, two Fe(III) atoms are connected by a bridging oxide O atom [bridging angle = 160.6 (4)°], and each Fe(III) atom is also coordinated by three Cl atoms, completing a distorted tetra-hedral geometry.

Transcriptional profiling suggests that Barrett's metaplasia is an early intermediate stage in esophageal adenocarcinogenesis

To investigate the relationship between Barrett's esophagus (BE) and esophageal adenocarcinoma (EAC), we determined gene expression profiles of discrete pathological stages of esophageal neoplasia using a sequence-verified human cDNA microarray. Fifty one RNAs, comprising 24 normal esophagi (NE), 18 BEs, and nine EACs were hybridized to cDNA microarrays. Five statistical analyses were used for the data analysis. Genes showing significantly different expression levels among the three sample groups were identified. Genes were grouped into functional categories based on the Gene Ontology Consortium. Surprisingly, the expression pattern of BE was significantly more similar to EAC than to NE, notwithstanding the known histopathologic differences between BE and EAC. The pattern of NE was clearly distinct from that of EAC. Thirty-six genes were the most differentially modulated, according to these microarray data, in BE-associated neoplastic progression. Twelve genes were significantly differentially expressed in cancer-associated BE's plus EAC (as a single combined tissue group) vs noncancer-associated BE's. These genes represent potential biomarkers to diagnose EAC at its early stages. Our results demonstrate that molecular events at the transcriptional level in BE are remarkably similar to BE's-associated adenocarcinoma of the esophagus. This finding alarmingly implies that BE is biologically closer to cancer than to normal esophagus, and that the cancer risk of BE is perhaps higher than we had imagined. These findings suggest that changes modulated at the molecular biologic level supervene earlier than histologic changes, and that BE is an early intermediate stage in the process of EAC.

Aberrant expression of p21(WAF1/CIP1) and p27(KIP1) in cervical carcinoma

An immuno-histochemical study of p21 and p27 expression in cervical carcinoma was performed in 73 patients. Positive p21 and p27 staining was detected in 35.6 and 11% of tumour tissues, respectively. p21 expression was significantly correlated with advanced disease stage and negative human papilloma virus infection whilst positive p27 staining was not correlated with any clinical and pathological parameters studied. Kaplan-Meier estimation indicated that survival might be related to disease stage, tumour grade and p21 expression. Cox regression analysis confirmed that advanced stage disease and poorly differentiated tumour are independent prognostic factors for cervical carcinoma.

[Construction and characterization of the chimeric protein consisting RGD-containing peptide and proUK]

On the basis of structure analysis and computer modeling of proUK, two-chain DNA fragment encoding RGD peptide was inserted into the corresponding proUK cDNA site between Gly118-Leu119, using site-directed mutagenesis and DNA recombinant techniques. The chimeric gene was expressed in methylotrophic yeast Pichia pastoris expression system. The chimeric protein was purified after two step purification of Zn2+ chelating column and SP cation exchange column. The specific activity was 65,000 IU/mg protein. The chimeric protein had somewhat lower catalytic efficiency (kcat/Km) on the substrate S2444 as compared to Urokinase. But it had high anti-platelet aggregation activity, and the half inhibit constant was 2.1 mumol/L. The results showed that the chimeric protein not only had higher thrombolytic activity but also obtained anti-thrombus function. Further evaluation of the thrombolytic and antithrombolytic potential in appropriate animal models seemed to be investigated.

Alteration of cyclin D1 and CDK4 gene in carcinoma of uterine cervix

Amplification and overexpression of cyclin D1 and CDK4 genes in cervical carcinoma were studied by semi-quantitative differential polymerase chain reaction assay and an immunostaining technique, respectively. Amplifications of cyclin D1 and CDK4 genes were found in 24% (27/113) and 26% (29/112) of tumors, respectively. Overexpression of cyclin D1 and CDK4 was demonstrated in 32% (21/66) and 73% (45/62) of tumors, respectively. No tumor showed CDK4 gene mutation on single strand conformational polymorphism. Sixteen percent (8/49) of the tumor specimens showed neither amplification nor overexpression. Disease stage, tumor grade and overexpression of cyclin D1 were found to be independent poor prognostic factors in cervical carcinoma.

[Application of a gel chromatography renaturing way on low molecular single-chain urokinase mutant(DscuPA-32K)]

A recombinant mutant gene with thrombolytic and antithrombolytic bifunction was expressed in E. coli. Owing to two reasons of high molecular weight and over expression, dscuPA existed in inclusion body form. The protein of inclusion body was inactive protein. In order to obtain active protein, inclusion bodies should be denatured and then renatured. We performed a novel way named gel-chromatography column renaturation way. Compare with traditional renaturation way, this refolding approach had some obvious advantages, such as low cost and high recovery, and accomplished the preliminary purification step of desired protein(DscuPA-32K). Especially to proteins that easily became inactive and degradation, this approach might have good prospect.

[Regeneration of HNP transgenic alfalfa plants by Agrobacterium mediated gene transfer]

Transgenic plants regenerated from cotyledons of M. sativa L. infected using Agrobacterium tumefaciens A281 with plasmid pBF649 containing a gene encoding protein of high sulfur-amino acid content (HNP) were obtained successfully. The plants grew and fertiled well in field. Cotyledon explants were better recipient for transformation of M. sativa L. Environment of suitable temperature (15 degrees C) and high humidity on high viability of the plants transplanted into soil were essential conditions.

Isolation and Characterization of a Type 1 Ribosome-Inactivating Protein from Fruiting Bodies of the Edible Mushroom (Volvariella volvacea)

A novel single-chained ribosome-inactivating protein (RIP) with a molecular weight of approximately 29 000 was purified from fruiting bodies of the edible mushroom Volvariellavolvacea with a procedure involving ammonium sulfate precipitation, ion-exchange chromatography on DEAE-cellulose, and gel filtration on Superdex 75. The mushroom RIP, designated volvarin, exhibited a potent inhibitory action on protein synthesis in the rabbit reticulocyte lysate system with an IC(50) value of 0.5 nM. Like most plant RIPs, volvarin acted as an N-glycosidase that depurinated rRNA from rabbit reticulocyte lysate, releasing a characteristic RNA fragment after treatment with aniline. It also exerted a deoxyribonuclease activity on supercoiled SV-40 DNA and demonstrated a strong abortifacient effect in mice.

[Leptotrombidium (L.) scutellare as the transmitting vector of tsutsugamushi disease of autumn-winter type in Jiangsu Province]

In 1986, epidemic of tsutsugamushi disease of autumn-winter type was found in Jiangsu province. To clarify the vector of this disease, we carried out a series of studies in 1986-1992. Leptotrombidium (L.) scutellare was found to be a dominant species of chigger mite on rats in the endemic areas and its seasonal distribution was correlated with the incidence of tsutsugamushi disease in inhabitants. This mite could naturally be infected by Rickettsia tsutsugamushi, and R. tsutsugamushi could be transmitted via biting and transovarial transmission. Specific antibodies could be detected in the sera of mice bitten by the mites or inoculated with the suspension of mites. Serological typing of the sera of mice was of Gilliam type. The above results demonstrate that L. (L.) scutellare can serve as transmitting vector of tsutsugamushi disease of autumn-winter type.