Hybrid FeWO4-Hyaluronic Acid Nanoparticles as a Targeted Nanotheranostic Agent for Multimodal Imaging-Guided Tumor Photothermal Therapy

Background

Development of versatile nanoplatform still remains a great challenge due to multistep synthesis and complicated compositions. Therefore, it is significant to develop a facile method to synthesize a nanocomposite to achieve multimodal imaging and even imaging-guided cancer therapeutics.

Methods and Results

In our study, hyaluronic acid-functionalized iron (II) tungstate nanoparticles (HA-FeWO4 NPs) were successfully synthesized as a versatile nanoplatform by a facile one-pot hydrothermal procedure. The formed multifunctional HA-FeWO4 NPs were investigated via a series of characterization techniques, which demonstrated good biocompatibility, excellent dispersion, low cytotoxicity, active tumor-targeting ability and high photothermal efficiency. Furthermore, tumor was clearly visualized by HA-FeWO4 NPs with multimodal imaging of infrared thermal imaging, magnetic resonance imaging, computed tomography imaging in 4T1 tumor bearing mice. More importantly, HA-FeWO4 could achieve multimodal imaging-guided photothermal therapy of 4T1 tumors.

Conclusion

The constructed HA-FeWO4 NPs have great potential as ideal nanotheranostic agents for multimodal imaging and even imaging-guided cancer theranostics in biological systems.

Quality of evidence supporting the role of acupuncture for breast cancer-related lymphoedema: an overview of systematic reviews and meta-analyses

BACKGROUND

Breast cancer-related lymphedema (BCRL) may benefit from acupuncture as a therapeutic. However, the findings of systematic reviews (SRs) and meta-analyses (MAs) are inconsistent and their quality needs to be evaluated critically. We aimed to provide an overview of the methodological quality, risk of bias, quality of reporting, and quality of evidence for SRs/MAs of acupuncture for BCRL.

METHODS

Publications were retrieved from four Chinese databases and four English databases. The methodological quality, risk of bias, reporting quality, and evidence quality of the included SRs/MAs were assessed by two independent researchers using the A Measurement Tool to Assess Systematic Reviews 2 (AMSTAR-2), Risk of Bias in Systematic Reviews (ROBIS), Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), and Grading of Recommendations, Assessment, Development and Evaluation (GRADE), respectively.

RESULTS

There were a total of 8 SRs/MAs included. By AMSTAR-2, all SRs/MAs were graded as having low or very low methodological quality. By ROBIS, all SRs/MAs in phase 1, domain 1, and domain 4 of phase 2 were at low risk, while in domain 2 were at high risk. By PRISMA, reporting weaknesses in protocol and registration, as well as search method, were identified. By GRADE, the level of evidence quality was "low" to "very low", and the most commonly downgraded factor was the risk of bias.

CONCLUSIONS

Acupuncture may be beneficial in improving BCRL. However, due to the identified limitations and conflicting findings, further more prescriptive and rigorous SRs/MAs are required to give strong evidence for final judgments.

Achieving safe and high-performance gastrointestinal tract spectral CT imaging with small-molecule lanthanide complex

BACKGROUND

Non-intrusive imaging of gastrointestinal (GI) tract using computed tomography (CT) contrast agents is of the most significant issues in the diagnosis and treatment of GI diseases. Moreover, spectral CT, which can generate monochromatic images to display the X-ray attenuation characteristics of contrast agents, provides a better imaging sensitivity for diagnose inflammatory bowel disease (IBD) than convention CT imaging.

METHODS

Herein, a convenient and one-pot synthesis method is provided for the fabrication of small-molecule lanthanide complex Holmium-tetraazacyclododecane-1, 4, 7, 10-tetraacetic acid (Ho-DOTA) as a biosafe and high-performance spectral CT contrast agent for GI imaging with IBD. In vivo CT imaging was administered with both healthy mice and colitis mice induced by dextran sodium sulfate.

RESULTS

We found that Ho-DOTA accumulated in inflammation sites of large intestines and produced high CT contrast compared with healthy mice. Both in vitro and in vivo experimental results also showed that Ho-DOTA provided much more diagnostic sensitivity and accuracy due to the excellent X-ray attenuation characteristics of Ho-DOTA compared with clinical iodinate agent. Furthermore, the proposed contrast media could be timely excreted from the body via the urinary and digestive system, keeping away from the potential side effects due to long-term retention in vivo.

CONCLUSION

Accordingly, Ho-DOTA with excellent biocompatibility can be useful as a potential high-performance spectral CT contrast agent for further clinical imaging of gastrointestinal tract and diagnosis of intestinal system diseases.

Pathological pseudoprogression to anti-PD-1 inhibitor in metastatic periampullary carcinoma: Case report

RATIONALE

Pseudoprogression has been deemed as a rare clinical phenomenon during the treatment of immune checkpoint inhibitors in patients with advanced cancers, especially in periampullary carcinoma, however, leaving potential molecular mechanism remain unknown.

PATIENT CONCERNS

Regular examination after radical pancreaticoduodenectomy because of periampullary carcinoma.

DIAGNOSES

Recurrent periampullary carcinoma with metastasis in liver.

INTERVENTIONS

Regimens of XELOX (oxaliplatin at a dose of 130 mg/m2, day 1 and oral capecitabine at a dose of 1000 mg/m2 twice a day, day 1-14, every 21 days), and tislelizumab at a dose of 200 mg, day 1, per 21 days, was prescribed as palliative treatment.

OUTCOMES

Pseudoprogression and symptom of hair and mustache repigmentation were also observed, which resulted in partial response finally.

LESSONS

Results of the present case suggested that pseudoprogression, along with hair and mustache repigmentation, possibly caused by anti-PD-1 inhibitors, may also happen in patients with periampullary carcinoma, which should be paid attention to. The potential mechanism should be further investigated.

Medial-lateral versus lateral-only pinning fixation in children with displaced supracondylar humeral fractures: a meta-analysis of randomized controlled trials

BACKGROUND

Supracondylar humeral fractures (SCHFs) are frequent in children, and closed reduction with percutaneous pin fixation remains the standard surgical treatment for displaced SCHFs. Two pinning configurations, medial-lateral crossed entry pinning (MLP) and lateral-only entry pinning (LP), are widely used, but which one is superior to another one is still debatable. This meta-analysis aimed to compare the efficacy and safety of both pinning fixation methods.

METHODS

Randomized controlled trials (RCTs) were searched on PubMed, EMBASE, Web of Science, Cochrane library and Google Scholar. Relative risk (RR) and mean difference (MD) with corresponding 95% confidence interval (CI) were calculated for radiographical outcomes, functional outcomes and complications.

RESULTS

A total of 19 RCTs comprising 1297 Gartland type II and type III fractures were included. MLP had a decreased risk of loss of reduction (RR = 0.70, 95%CI 0.52-0.94, P = 0.018) but a higher risk of iatrogenic ulnar nerve injury (RR = 2.21, 95%CI 1.11-4.41, P = 0.024) than LP. However, no significant difference was observed for incidence of ulnar nerve injury if applying a mini-open technique in MLP group (RR = 1.73, 0.47-6.31, P = 0.407). There were no differences between both groups in loss of carrying angle (MD = - 0.12, 95%CI - 0.39 to 0.16), loss of Baumann angle (MD = 0.08, 95%CI - 0.15 to 0.30), excellent grading of Flynn criteria (RR = 1.06, 95%CI 0.99-1.14, P = 0.102) and pin tract infection (RR = 0.92, 95%CI 0.50-1.70).

CONCLUSIONS

MLP is more effective in maintaining fixation, while LP is safer with respect to ulnar nerve injury. MLP with a mini-open technique reduces the risk of ulnar nerve lesion and is an effective and safe choice.

Radiomics model based on features of axillary lymphatic nodes to predict axillary lymphatic node metastasis in breast cancer

BACKGROUND

Breast cancer (BC) is among the most common cancers worldwide. Machine learning-based radiomics model could predict axillary lymph node metastasis (ALNM) of BC accurately.

PURPOSE

The purpose is to develop a machine learning model to predict ALNM of BC by focusing on the radiomics features of axillary lymphatic node (ALN).

METHODS

A group of 398 BC patients with 800 ALNs were retrospectively collected. A set of patient characteristics were obtained to form clinical factors. Three hundred and twenty-six radiomics features were extracted from each region of interest for ALN in contrast-enhanced computed tomography (CECT) image. A framework composed of four feature selection methods and 14 machine learning classification algorithms was systematically applied. A clinical model, a radiomics model, and a combined model were developed using a cross-validation approach and compared. Metrics of the area under the curve (AUC), accuracy, sensitivity, and specificity were calculated to evaluate the performance of these models in the prediction of ALNM in BC.

RESULTS

Among the 800 cases of ALNs, there were 388 cases of positive metastasis (48.50%) and 412 cases of negative metastasis (51.50%). The baseline clinical model achieved the performance with an AUC = 0.8998 (95% CI [0.8540, 0.9457]). The radiomics model achieved an AUC = 0.9081 (95% CI [0.8640, 0.9523]). The combined model using the clinical factors and radiomics features achieved the best results with an AUC = 0.9305 (95% CI [0.8928, 0.9682]).

CONCLUSIONS

Combinations of feature selection methods and machine learning-based classification algorithms can develop promising predictive models to predict ALNM in BC using CECT features. The combined model of clinical factors and radiomics features outperforms both the clinical model and the radiomic model.

The GC2 haplotype of the vitamin D binding protein is a risk factor for a low plasma 25-hydroxyvitamin D concentration in a Han Chinese population

Background

The GC haplotype of the vitamin D binding protein (encoded by the GC gene) might be a risk factor to the vitamin D (VD) nutritional status for many populations, while evidences from the Chinese Han population are sparse. We test the association between vitamin D binding protein genotypes and VD status as well as the metabolic parameters of glucose and lipids in a Han Chinese population.

Methods

In a cross-sectional study conducted at a health examination centre (registered in ClinicalTrials.gov as QLS2013), 2641 adults were included and grouped according to their plasma 25-hydroxyvitamin D (25OHD) concentrations as VD deficient (VDD), insufficient (VDI), or sufficient (VDS). The rs7041 and rs4588 genotypes were analysed with a molecular beacon-based qPCR method using blood samples.

Results

Plasma 25OHD concentrations were lower in the GC2/2, rs7041T/T, and rs4588A/A genotypes than the GC1f/1s, rs7041G/T, and rs4588C/C genotypes (P <  0.05). After adjusting for confounders, the GC2 haplotype increased the risk of low VD status (P <  0.05) in both genders. More genotypic models revealed the negative contributions of rs4588A than rs7041T to low VD status (P <  0.05). The combined rates of VDD and VDI were 80.2% in males and 86.1% in females. Compared with VDI, VDS, or both, VDD showed higher plasma concentrations of fasting blood glucose, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and triglycerides in males (P <  0.05); however, no significant differences were found with regard to these parameters between the subgroups defined by the GC genotypes (P > 0.05).

Conclusions

In a Han Chinese population, the GC2 haplotype or more exactly rs4588A is a risk factor for low VD status but is not associated with glucose and lipid metabolic disorders, which are inversely correlated with the circulating 25OHD concentration in males.

Trial registration

The study was retrospectively registered in January 2018 as NCT03406234 in the ClinicalTrials.gov online system.

Electronic supplementary material

The online version of this article (10.1186/s12986-019-0332-0) contains supplementary material, which is available to authorized users.

Exosomes promote cetuximab resistance via the PTEN/Akt pathway in colon cancer cells

Cetuximab is widely used in patients with metastatic colon cancer expressing wildtype KRAS. However, acquired drug resistance limits its clinical efficacy. Exosomes are nanosized vesicles secreted by various cell types. Tumor cell-derived exosomes participate in many biological processes, including tumor invasion, metastasis, and drug resistance. In this study, exosomes derived from cetuximab-resistant RKO colon cancer cells induced cetuximab resistance in cetuximab-sensitive Caco-2 cells. Meanwhile, exosomes from RKO and Caco-2 cells showed different levels of phosphatase and tensin homolog (PTEN) and phosphor-Akt. Furthermore, reduced PTEN and increased phosphorylated Akt levels were found in Caco-2 cells after exposure to RKO cell-derived exosomes. Moreover, an Akt inhibitor prevented RKO cell-derived exosome-induced drug resistance in Caco-2 cells. These findings provide novel evidence that exosomes derived from cetuximab-resistant cells could induce cetuximab resistance in cetuximab-sensitive cells, by downregulating PTEN and increasing phosphorylated Akt levels.

Meta-analysis for the efficacy of S-1-based regimens as the first-line treatment in Asian chemotherapy-naive patients with advanced non-small-cell lung cancer

AIM

We performed a meta-analysis to evaluate the efficacy and safety for S-1-based regimens as the first-line treatment in Asian chemotherapy-naive patients with advanced non-small-cell lung cancer.

PATIENTS & METHODS

Eligible randomized clinical trials (RCTs) were included, of which data were extracted by inclusion criteria and exclusion one. Odds ratio and hazard ratio (HR) of outcomes including objective response rate (ORR), progression-free survival (PFS), overall survival (OS) and adverse effects (AEs) were explored for the final analysis.

RESULTS

Twenty-one RCTs including 3263 patients were fit into the analysis. Pooled HR for PFS was 1.01 (95% CI: 0.92-1.10; p = 0.88), the pooled HR for OS was 0.95 (95% CI: 0.85-1.06; p = 0.33) and the pooled odds ratio for ORR was 0.74 (95% CI: 0.61-0.90; p = 0.003). S-1-based regimens showed milder AEs in high-grade nausea/vomit, anorexia, leukopenia, neutropenia and febrile neutropenia (all p < 0.05).

CONCLUSION

The present study has revealed that S-1-based regimens are accompanied by the similar efficacy and slighter AEs compared with standard regimens as the first-line treatment in Asian chemotherapy-naive patients with advanced non-small-cell lung cancer.

[Surgical treatment and prognosis of pancreatic neuroendocrine carcinoma]

Objective: Pancreatic neuroendocrine carcinoma (pNEC) is a highly malignant tumor.This study aimed to evaluate the role of surgery and the prognosis for patients with pancreatic neuroendocrine carcinoma (pNEC). Methods: We collected and reviewed all clinical data of patients who underwent radical surgery for pNEC from Jan 2000 through Jan 2016 in our hospital. Cox-regression analysis wasused to evaluate the factors potentially influencing survival. Results: Twenty patients including 11 males and 9 females (median age, 62.5 years) were included in this study. All patients underwent radical surgery and 17 cases received postoperative platinum-based chemotherapy.The median follow-up time was 41 months (range, 1 to 127 months). The 1-, 3-, and 5-year survival rates of the patients were 66.7%, 51.5% and 28.1%, with a median survival time of 75.3 months.The multivariate analysis indicated that tumor size and Ki-67 index were of prognostic significance. Conclusions: Pancreatic neuroendocrine carcinomas are rare but increasing in incidence. Patients with localized nonmetastatic primary tumors seem to benefit from surgery. Early diagnosis and multimodality therapy are key points of an improved survival.

Moderating factors influencing adoption of a mobile chronic disease management system in China

Mobile chronic disease management systems (MCDMS) have become increasingly important in recent years, but in China, challenges remain for their adoption. Existing empirical studies have not completely explored the adoption behavior of potential MCDMS users. This article presents a study in which we investigated factors that influence chronically ill patients in China and their families to adopt or decline to use MCDMS. We applied a research model based on the technology acceptance model (TAM) as well as four contextual constructs (perceived disease threat, perceived risk, initial trust, and technology anxiety) to a survey of 279 potential MCDMS service participants in China. Our key findings include: (1) as consistent with current research, both perceived usefulness and perceived ease of use have positive impact on potential users' MCDMS adoption intention; (2) both perceived disease threat and initial trust have positive impact on MCDMS adoption intention; (3) the impact of perceived risk is negative, and technology anxiety has negative impact on perceived ease of use of MCDMS; (4) young people place more importance on their perceptions of usefulness, ease of operation, and disease threat than middle-aged and older users; (5) family members are more influenced by their perception of ease of use and disease threat than chronically ill patients, while chronically ill patients place more importance on perceived usefulness than family members. This article concludes by discussing the implications of our study for research and practice, as well as limitations and future research directions.

Simulation Studies of Protein and Small Molecule Interactions and Reaction

Computational studies of protein and small molecule (protein-ligand/enzyme-substrate) interactions become more and more important in biological science and drug discovery. Computer modeling can provide molecular details of the processes such as conformational change, binding, and transportation of small molecules/proteins, which are not easily to be captured in experiments. In this chapter, we discussed simulation studies of both protein and small molecules from three aspects: conformation sampling, transportations of small molecules in enzymes, and enzymatic reactions involving small molecules. Both methodology developments and examples of simulation studies in this field were presented.

No Sun-like dynamo on the active star ζ Andromedae from starspot asymmetry

Sunspots are cool areas caused by strong surface magnetic fields that inhibit convection. Moreover, strong magnetic fields can alter the average atmospheric structure, degrading our ability to measure stellar masses and ages. Stars that are more active than the Sun have more and stronger dark spots than does the Sun, including on the rotational pole. Doppler imaging, which has so far produced the most detailed images of surface structures on other stars, cannot always distinguish the hemisphere in which the starspots are located, especially in the equatorial region and if the data quality is not optimal. This leads to problems in investigating the north-south distribution of starspot active latitudes (those latitudes with more starspot activity); this distribution is a crucial constraint of dynamo theory. Polar spots, whose existence is inferred from Doppler tomography, could plausibly be observational artefacts. Here we report imaging of the old, magnetically active star ζ Andromedae using long-baseline infrared interferometry. In our data, a dark polar spot is seen in each of two observation epochs, whereas lower-latitude spot structures in both hemispheres do not persist between observations, revealing global starspot asymmetries. The north-south symmetry of active latitudes observed on the Sun is absent on ζ And, which hosts global spot patterns that cannot be produced by solar-type dynamos.

Cytokine network analysis of cerebrospinal fluid in myalgic encephalomyelitis/chronic fatigue syndrome

Myalgic encephalomyelitis/chronic fatigue syndrome is an unexplained debilitating disorder that is frequently associated with cognitive and motor dysfunction. We analyzed cerebrospinal fluid from 32 cases, 40 subjects with multiple sclerosis and 19 normal subjects frequency-matched for age and sex using a 51-plex cytokine assay. Group-specific differences were found for the majority of analytes with an increase in cases of CCL11 (eotaxin), a chemokine involved in eosinophil recruitment. Network analysis revealed an inverse relationship between interleukin 1 receptor antagonist and colony-stimulating factor 1, colony-stimulating factor 2 and interleukin 17F, without effects on interleukin 1α or interleukin 1β, suggesting a disturbance in interleukin 1 signaling. Our results indicate a markedly disturbed immune signature in the cerebrospinal fluid of cases that is consistent with immune activation in the central nervous system, and a shift toward an allergic or T helper type-2 pattern associated with autoimmunity.

Preliminary Survey of Ectoparasites and Associated Pathogens from Norway Rats in New York City

The Norway rat (Rattus norvegicus) is a reservoir of many zoonotic pathogens and lives in close proximity to humans in urban environments. Human infection with rodent-borne disease occurs either directly through contact with a rat or its excreta, or indirectly via arthropod vectors such as fleas and ticks. Here, we report on the diversity and abundance of ectoparasitic arthropod species and associated pathogenic bacteria from 133 Norway rats trapped over a 10-mo period in Manhattan, New York, NY. Norway rats were host to the tropical rat mite [Ornithonyssus bacoti (Hirst)], the spiny rat mite (Laelaps echidnina Berlese), Laelaps nuttalli Hirst, the spined rat louse [Polyplax spinulosa (Burmeister)], and the Oriental rat flea [(Xenopsylla cheopis) (Rothschild)], with an average of 1.7 species per individual. A flea index of 4.1 X. cheopis was determined, whereas previous studies in New York City reported 0.22 fleas per rat. Multiple species of pathogenic Bartonella were identified from Oriental rat fleas that were related to Bartonella tribocorum, Bartonella rochalimae, and Bartonella elizabethae. However, no evidence of Yersinia pestis or Rickettsia spp. infection was detected in fleas. The identification of multiple medically important ectoparasite species in New York City underscores the need for future efforts to fully characterize the diversity and distribution of ectoparasites on Norway rats, and assess the risk to humans of vector-borne disease transmission.

Generalized linear mixed models for mapping multiple quantitative trait loci

Many biological traits are discretely distributed in phenotype but continuously distributed in genetics because they are controlled by multiple genes and environmental variants. Due to the quantitative nature of the genetic background, these multiple genes are called quantitative trait loci (QTL). When the QTL effects are treated as random, they can be estimated in a single generalized linear mixed model (GLMM), even if the number of QTL may be larger than the sample size. The GLMM in its original form cannot be applied to QTL mapping for discrete traits if there are missing genotypes. We examined two alternative missing genotype-handling methods: the expectation method and the overdispersion method. Simulation studies show that the two methods are efficient for multiple QTL mapping (MQM) under the GLMM framework. The overdispersion method showed slight advantages over the expectation method in terms of smaller mean-squared errors of the estimated QTL effects. The two methods of GLMM were applied to MQM for the female fertility trait of wheat. Multiple QTL were detected to control the variation of the number of seeded spikelets.

Expression of elevated levels of pro-inflammatory cytokines in SARS-CoV-infected ACE2+ cells in SARS patients: relation to the acute lung injury and pathogenesis of SARS

The authors have previously shown that acute lung injury (ALI) produces a wide spectrum of pathological processes in patients who die of severe acute respiratory syndrome (SARS) and that the SARS coronavirus (SARS‐CoV) nucleoprotein is detectable in the lungs, and other organs and tissues, in these patients. In the present study, immunohistochemistry (IHC) and in situ hybridization (ISH) assays were used to analyse the expression of angiotensin‐converting enzyme 2 (ACE2), SARS‐CoV spike (S) protein, and some pro‐inflammatory cytokines (PICs) including MCP‐1, TGF‐β1, TNF‐α, IL‐1β, and IL‐6 in autopsy tissues from four patients who died of SARS. SARS‐CoV S protein and its RNA were only detected in ACE2⁺ cells in the lungs and other organs, indicating that ACE2‐expressing cells are the primary targets for SARS‐CoV infection in vivo in humans. High levels of PICs were expressed in the SARS‐CoV‐infected ACE2⁺ cells, but not in the uninfected cells. These results suggest that cells infected by SARS‐CoV produce elevated levels of PICs which may cause immuno‐mediated damage to the lungs and other organs, resulting in ALI and, subsequently, multi‐organ dysfunction. Therefore application of PIC antagonists may reduce the severity and mortality of SARS. Copyright © 2006 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

[Laser-induced fluorescence detection in micro-column separation]

Laser-induced fluorescence detection (LIFD) has been used extensively in micro-column separation due to its high sensitivity and selectivity. A review is presented on the present status and the trends of development of LIF detector with 52 references cited. The detection cells of the LIFD are mainly discussed.

[Prognosis of patients with primary liver carcinoma treated with local resection]

OBJECTIVE

To discuss the prognosis of primary liver carcinoma treated with local resection and factors affecting prognosis.

METHODS

The data on 130 patients who had been treated from October 1989 to October 1995 were reviewed retrospectively.

RESULTS

Curative local resection was performed in 130 patients. Death rate of operation was 0.7%, and the incidence of complications 16.1% (n = 18). The overall 1-, 3- and 5-year survival rates were 82.1%, 60.6% ,48.2%, respectively. Involvement of blood vessels or liver capsules as well as the increase of AST before operation are the significant factors affecting prognosis (P < 0.05).

CONCLUSIONS

Local resection is a method characterized by little damage, less bleeding, less complication and good prognosis.

[Study on the characters of hydrogen bonds in protein and nucleic acid of the breast cancer tissues]

Some remarkable spectral differences are observed between the normal breast tissues and breast cancer tissues, including those of association pattern and degree of the hydrogen bonds in the protein and nucleic acid biomacromolecules. These differences are found in the relative intensity, absorption position and shape of the characteristic bands: (1) amide I band, stretching vibration bands of N-H group and C-O(H) in the residues of some amino-acids, and (2) the relative intensity of asymmetric stretching vibration of the phosphodiester group in nucleic acid. The hydrogen bond is the major force which maintain and promote the formation of the high structure of protein and nucleic acid. It is possible to diagnose the breast cancer and forecast the possibility of canceration using above spectral characters of the hydrogen bond with other spectral characters.

Monocyte chemoattractant protein-1 expressed in neurons and astrocytes during focal ischemia in mice

Focal cerebral ischemia elicits an inflammatory response characterized by the infiltration and accumulation of leukocytes, as well as the secretion of inflammatory mediators (Clark et al., Brain Res. Bull., 35 (1994) 387-392; Garcia et al., Am. J. Pathol., 144 (1994) 188-199; Wang et al., J. Neurochem. 71 (1998) 1194-1204). Leukocytes eliminate microbial invaders and necrotizing tissue debris, and can also turn against surrounding healthy tissue and exacerbate tissue injury (Furie and Randolph, Am. J. Pathol., 146 (1995) 1287-1301; Kochanek and Hallenbeck, Stroke 23 (1992) 1367-1379). Inflammatory mediators are considered to play an important role in attracting and stimulating leukocytes (Weiss, N. Engl. J. Med., 320 (1989) 365-376). Monocyte chemoattractant protein-1 (MCP-1) functions as an inflammatory mediator, whose source and role in focal cerebral ischemia is worth studying. MCP-1, a potent chemoattractant factor, may play an important role in ischemia-induced inflammatory response. The aim of the present study is to determine the time course and cell type of MCP-1 protein expression after permanent focal ischemia in mice. ELISA and immunohistochemical staining were used to detect the expression of MCP-1 protein after 0 h, 2 h, 4 h, 12 h, 1 day, 2 days, 3 days, 5 days and 7 days of middle cerebral artery occlusion (n=3-5 in each group). Double-labeled fluorescent staining was used to examine the cellular localization of MCP-1. The results demonstrated that MCP-1 expression was mainly observed in the ischemic core after 12 h of middle cerebral artery occlusion, then gradually increased and extended to the ischemic perifocal area. MCP-1 expression peaked at 2 days and 3 days, and gradually decreased after 5 days of MCAO. Double-labeled immunostaining for MCP-1 and neuron specific enolase (NSE) or glial fibrillary acidic protein (GFAP) showed that MCP-1 positive neurons were observed as early as 12 h of ischemia, while MCP-1 positive astrocytes were observed after 2 days of ischemia. These results support the functional role of MCP-1 in ischemic brain injury and reveal a distinct temporal and spatial expression of MCP-1 in cells believed to be neurons and astrocytes.

5'-coterminal subgenomic RNAs in citrus tristeza virus-infected cells

Three unusual 5' coterminal positive-stranded subgenomic (sg) RNAs, two of about 0.8 kb and one of 10 kb (designated LMT1, LMT2, and LaMT, respectively), from Citrus spp. plants and Nicotiana benthamiana protoplasts infected with Citrus tristeza virus (CTV) were characterized. The 5' termini of the LMT RNAs were mapped by runoff reverse transcription and found to correspond with the 5' terminus of the genomic RNA. The LMT 5'-coterminal sgRNAs consisted of two modal lengths of 744--746 and 842--854 nts. The 3' of the LaMT RNAs terminated near the junction of ORF 1b and ORF 2 (p33). None of the 5' sgRNAs had detectable amounts of corresponding negative-sense RNAs, as occurs with the genomic and 3' coterminal subgenomic RNAs of CTV. The abundance of the short and long 5' sgRNAs differed considerably in infected cells. The LMT RNAs were considerably more abundant than the genomic RNAs, while the larger LaMT RNA accumulated to much lower levels. The kinetics of accumulation of LMT1 and LMT2 in synchronously infected protoplasts differed. The larger RNA, LMT1, accumulated earlier with a strong hybridization signal at 2 days postinfection, a time when only traces of genomic and 3' sgRNAs were detected. The lack of corresponding RNAs, that could be 3' cleavage products corresponding to the 5' coterminal sgRNAs and the lack of complementary negative strands, suggest that these sgRNAs were produced by termination during the synthesis of the genomic positive strands.

Clinical importance of preoperative carcinoembryonic antigen and carbohydrate antigen 19-9 levels in gastric cancer

Although serum carcinoembryonic antigen (CEA) and carbohydrate antigen (CA) 19-9 are commonly measured before surgery for gastric carcinoma, this clinical significance is not fully understood. We evaluated a total of 549 patients with gastric cancer who underwent gastrectomy. Levels of CEA and CA19-9 were measured preoperatively in all patients. We retrospectively analyzed correlations between CEA or CA19-9 and clinicopathologic features, and estimated the prognostic utility of the tumor markers by analyzing clinicopathologic characteristics of the carcinoma as a function of seropositivity or negativity of the antigens in combination or by raising the levels. The positivity rates of CEA (> or =5 ng/mL) and CA19-9 (> or =37 U/mL) were 19.5% and 18%, respectively. Serum CEA and CA19-9 positivity significantly correlated with depth of invasion, hepatic metastasis, and curativity. Forty-nine patients positive for both CEA and CA19-9 had significantly higher frequencies of lymph node metastasis, deeper invasion by the tumor, lower rates of curative resection (p < 0.01), and higher rates of hepatic metastasis (p < 0.05) than 377 patients with normal levels of CEA and CA19-9. Surgical outcomes of patients who were CEA- and CA19-9-positive were poorer than those of patients with normal CEA and CA19-9 levels (p < 0.01). Significant correlation was found between serum CEA and CA19-9 level (p < 0.001, r = 0.24). Doubling the threshold level of serum positivity to 10 ng/mL (CEA) and 74 U/mL (CA19-9) improved the prognostic value of these factors. However, multivariate analysis using Cox's hazards model revealed that only CEA positivity using the doubled threshold value (10 ng/mL) (p = 0.04, hazard ratio = 1.7), nodal involvement (p = 0.01, hazard ratio = 1.9), and depth of invasion (p = 0.02 hazard ratio = 1.5) significantly predicted prognosis. Carcinoembryonic antigen positivity using the doubled threshold level (10 ng/mL) was an important prognostic factor in patients with gastric cancer.

Down-regulation of E-cadherin by antisense oligonucleotide enhances basement membrane invasion of pancreatic carcinoma cells

Pancreatic carcinoma shows a marked invasiveness around tissues lymph node and/or hematogenous metastases resulting in poor prognoses of the patients. We examined on whether E-cadherin is associated with these malignant behaviors of pancreatic carcinoma cells using a human pancreatic adenocarcinoma cell line, JHP-1. Immunohistochemically, E-cadherin expression of JHP-1 cells was remarkably inhibited by treatment with E-cadherin antisense oligonucleotide. By invasion-MTT assay, JHP-1 cells treated with E-cadherin antisense oligonucleotide showed a significant increase of invasiveness compared to those treated with the control oligonucleotide (P < 0.001), whereas the proliferation of JHP-1 cells was not affected by the presence of either E-cadherin antisense or control oligonucleotide. Thus, down-regulation of E-cadherin of pancreatic carcinoma cells induced the invasiveness into the basement membrane. These results suggest that the reduction in E-cadherin expression plays a key role not only in detachment of cell-cell adhesion but also in invasion and metastasis of pancreatic carcinoma cells.

Prognostic value of intratumoral natural killer cells in gastric carcinoma

BACKGROUND

Natural killer (NK) cells are a group of effector cells that act nonspecifically against tumor cells. The correlation between intratumoral NK cell infiltration and clinicopathologic features remains unclear.

METHODS

The authors selected 146 patients with gastric carcinoma who underwent gastrectomy at Kagoshima University Hospital between 1985-1995. Immunohistochemical staining with the CD57 antibody was performed for the evaluation of NK cell infiltration. A total of 25 areas containing CD57 positive cells were selected and the number of NK cells were counted (magnification, x200). The patients were divided into 2 groups: patients with a high level of NK infiltration (n = 39) (>25 NK cells/25 high-power fields [HPF]) and patients with a low level of NK infiltration (n = 107) (<25 NK cells/25 HPF). Intratumoral lymphocytic infiltration also was counted in 25 areas at a magnification of x200. Patients were classified into a high infiltrating lymphocyte (IL) group (n = 69) (>150 cells/HPF) and a low IL group (n = 77) (<150 cells/HPF). The Kaplan-Meier curve was used to analyze surgical outcome. Multivariate analyses were performed to evaluate prognostic factors.

RESULTS

Patients with a high level of NK infiltration had a higher rate of early gastric carcinoma, fewer metastases to the lymph nodes (P < 0.01), and less lymphatic invasion (P < 0.05) than patients with a low level of NK infiltration. NK cell infiltration also was found to correlate with depth of invasion, clinical stage, and venous invasion. There was no correlation between NK cells and lymphocytic infiltration (P = 0.07; correlation coefficient = 0.15). The 5-year survival rate of patients with a high rate of NK infiltration was 78%, which was significantly better than that of patients with a low level of NK infiltration (P < 0.01). Multivariate analysis did not show NK cell infiltration to be a significant prognostic factor. Combination analysis of the number of NK cells and lymphocytic infiltration was shown to be an independent prognostic factor (P = 0.02; hazard ratio = 1.32).

CONCLUSIONS

Patients with a high level of NK infiltration were found to have a better prognosis than those with a low level of NK infiltration. Combination analysis with lymphocytic infiltration may provide useful information regarding the immunologic condition of patients with gastric carcinoma.

[The application quantitative structure-retention relationship of GC to aid MS qualitative analysis]

In this paper, a method, based on the prediction of the Kovats retention indices of related polysubstituted alkylbenzenes from the indices of benzene, monsubstituted alkylbenzenes and disubstituted alkylbenzenes, was used to aid qualitative analysis with mass spectrometry alone. A disproportinated aromatic product and the basic compounds of alkylbenzene were analyzed with gas chromatography isothermally at 100 degrees C separately. In order to cut down the analysis time and increase the resolution, the disproportionated aromatic product was analyzed using temperature programming with gas chromatographymass spectrometry (GC-MS). The Kovats retention indices of the basic compounds were determined and those of the polysubstituted alkylbenzenes were predicted with the method which was proposed by us previously. The isomers of polysubstituted alkylbenzenes have similar mass spectra, so they can not be identified unambiguously by MS alone. For the differences of the Kovats retention index between isomers of polysubstituted alkylbenzenes are larger, it can be identified by matching the experimental retention indices with the predicted ones. The positional isomers of polysubstituted alkylbenzenes which are very difficult to be interpreted by MS alone have been identified explicitly.

Treatment of hepatocellular carcinoma with the cellular tumor vaccines generated by in vitro modification of tumor cells with non gene transfer approaches

Anti-tumor immune responses are mediated primarily by T cells. Down regulation of major histocompatibility complex (MHC) and the molecules that costimulate the immune responses is associated with defective signaling of tumor cells for T cell activation. In vitro fusion of autologous tumor cells with antigen presenting cells (APCs) or treatment of tumor cells with a combination of cytokines significantly increased the expression of MHC class I and adhesion molecules on tumor cell surfaces that costimulate host immune responses. The hybrid cells generated by fusion of tumor cells with APCs and the tumor cells treated in vitro with a combination of cytokines and pre-incubated with a bispecific monoclonal antibody (bi-Mab) cross-linking antigen on tumor cells to CD28 on T cells, become immunogenic and able to stimulate naive T cells with generation of tumor specific cytotoxic T cells both in vitro and in vivo. Immunization with the modified tumor cells elicits an immune response mediated by both CD4+ and CD8+ T cells. This response protected against a parental tumor cell challenge and cured established tumors. The approach was effective in both low immunogenic and non-immunogenic tumor systems. Modification of tumor cells with tumor:APC fusion or the two-step procedure may provide a strategy for development of tumor vaccines that is effective for cancer immunotherapy.

D-RNA molecules associated with subisolates of the VT strain of citrus tristeza virus which induce different seedling-yellows reactions

Citrus tristeza virus (CTV) strains were previously catalogued as seedling-yellows (SY) and non-SY (nSY) types, according to their yellowing and stunting effects on indicator seedlings. Among subisolates of the VT strain, which were selected from chronically infected Alemow plants, there was a correlation between the presence of 2.4-, 2.7- and 4.5-kb D-RNAs, and SY and nSY reactions, respectively. Similarly, plants infected with Mor-T subisolates, which cause SY, contained D-RNAs of 2.6 to 2.8 kb, while nSY subisolates from recovered sour orange tissue contained a major D-RNA of 5.1 kb. Plants harboring the 2.7-kb D-RNA were protected against challenge inoculation with a subisolate harboring the 4.5-kb D-RNA. This study suggests that the nSY reaction results either from the absence of SY gene(s) in the genomes of certain CTV strains or through the suppression of the effects of SY gene(s) by D-RNAs with 5' parts larger than 4000nt.

Tumor angiogenesis related to growth pattern and lymph node metastasis in early gastric cancer

OBJECTIVE

To investigate the correlation between angiogenesis and tumor growth pattern as well as the lymph node metastasis to reveal the significance of vascularity in the early stage of gastric cancer.

METHODS

97 specimens from patients with early gastric cancer were studied by immunohistochemical method using anti-factor VIII related antigen antibody.

RESULTS

Microvessel count was related to tumor growth pattern. The mean vessel count was higher in superficially spreading and penetrating types of tumors. Lymph node metastasis was correlated to microvessel count. Tumors with lymph node metastasis had higher microvessel counts than those without lymph node metastasis.

CONCLUSIONS

In the early stage of gastric carcinoma, angiogenesis is correlated with tumor growth pattern and lymph node metastasis. Identification of tumors with high density of vascularization is beneficial for closer follow-up and adjuvant therapy.

Expression of thymidine phosphorylase is associated with a poor prognosis in patients with ductal adenocarcinoma of the pancreas

Thymidine phosphorylase (dThdPase) is identical to platelet-derived endothelial cell growth factor and has angiogenic activity. In this study, we investigated the expression of dThdPase in ductal adenocarcinoma of the pancreas and examined the correlation between dThdPase expression and clinicopathological factors and clinical outcome. dThdPase expression was demonstrated by immunohistochemistry in the cytoplasm of tumor cells in 59% of the 54 patients studied. The expression of dThdPase correlated significantly with a poor prognosis (P=0.013). Significant correlations were also observed between dThdPase expression and extrapancreatic neural plexus invasion and the presence of postoperative hepatic metastases (P=0.05 and 0.03, respectively). The average microvessel count in dThdPase-positive tumors was significantly higher than that in dThdPase-negative tumors (P < 0.0001). These findings suggest that dThdPase expression in pancreatic adenocarcinoma enhances the abilities of tumor invasion and/or metastasis through its angiogenic properties.

[The study of relation of the retention indices of n-alkenes with their molecular structure]

When the difference values between the retention indices of homologous series of n-alkenes and that of n-alkanes with the same carbon number were plotted with the number of carbon atoms in the molecule, it can be seen that the curve is nearly an exponential curve. We proposed an accurate formula to predict the retention indices of homologous series of n-alkenes. The retention indices of a total of 99 C12-C16 n-alkenes on capillary columns with stationary phase of Squalane, PFE and PEG-4000 were calculated. The standard deviations of the retention indices were +/-0.9-+/-1.5 index units. When the retention indices of n-alkenes with the same carbon numbers and the same geometric structure were plotted with the positions of the double bond in the molecule, it can be seen that the curve is also approximately an exponential curve. Therefore, we put forward an exact formula to predict the retention indices of the n-alkenes. The universality of the formula is demonstrated by predicting a total of 178 retention indices of C15-C18 n-alkenes on capillary columns with stationary phases of C87 hydrocarbon, Apiezonl L, CW-20M. The standard deviations of retention indices were +/-0.9-+/-1.2 index units.

Comparison of p53 expression in proximal and distal gastric cancer: histopathologic correlation and prognostic significance

BACKGROUND

The overexpression of p53 has been found to be correlated with prognosis of some carcinomas, including gastric cancer, but no studies have reported on its relationship to the location of gastric cancer. In the present study, we compared the p53 expression of proximal and distal gastric cancer concerning histopathology and prognosis.

METHODS

A total of 170 tumors in the patients with proximal (80 cases) and distal (90 cases) gastric cancer were studied by immunohistochemical methods.

RESULTS

p53 immunopositivity was detected in 28.8% of all tumors. The p53-positive expression in proximal gastric cancer was higher than in distal gastric cancer (38.8% vs. 20.0%, p < 0.05). A 5-year survival analysis showed that there is no significant difference between tumors that are p53 positive and p53 negative. No correlation was found between p53 expression and histopathology of gastric cancer.

CONCLUSION

p53 nuclear staining is not useful as a prognostic indicator or as a parameter in gastric cancer.

Inhibition of human melanoma growth and metastasis in vivo by anti-CD44 monoclonal antibody

CD44 is a M(r) 90,000 surface glycoprotein believed to be involved in cell adhesion and migration. We investigated the role of CD44 in tumor growth and metastasis using human melanoma cell lines SMMU-1 and SMMU-2. Both SMMU-1 and SMMU-2 form tumors in the s.c. tissues when injected s.c. in SCID mice but only SMMU-2 metastasizes. Approximately one-half of SCID mice receiving injections of SMMU-2 s.c. develop metastatic tumors. SMMU-2 but not SMMU-1 expresses high levels of the hematopoietic form of CD44 and binds fluorescence-conjugated hyaluronic acid in vitro. GKW.A2 is a monoclonal antibody specific for human CD44 that can completely inhibit the binding of hyaluronic acid to SMMU-2 tumor cells in vitro. Moreover, in vivo injection of GKW.A3 inhibited the growth and metastatic potential of SMMU-2 tumor cells. Administration of GKW.A3 i.v. 1 week after s.c. tumor injection did not inhibit local tumor development but inhibited the formation of metastatic tumors and prolonged animal survival. Therefore, interactions between CD44 on tumor cells and its ligands in vivo may be necessary for tumor growth and metastasis.

[A population-based study on types of viral hepatitis]

The epidemiological features of various types of acute viral hepatitis in 5 regions of Sichuan Province (211,639) population) form Feb.16, 1987 to Feb 15, 1988 were studied. One-year surveillance was carried out and the results showed an incidence rate of 167.74 per 100,000 for acute viral hepatitis. The proportional distribution of HA,HB,non-A,non-B Hepatitis (HNANB), Hepatitis with EBV (HEB), Hepatitis with CMV (HCM) and Mixed infection in all the patients being 24.51%, 38.31%, 24.51%, 3.38%, 3.38% and 5.92%, respectively. There was a proportion of 14.93% for superinfection. The incidence differences in these regions ranged from 110.30 per 100,000 to 299.95 per 100,000. The incidence of hepatitis peaked in spring, and the sex ratio (male:female) for acute viral hepatitis was 1.75:1 (P less than 0.001). There was a peak of attack rate for HA in 0-19 age group. The incidence of HB in 20-39 age group was obviously higher than that in other age groups. For HNANB, a relatively high attack rate was noticed in 5-19 age group, but no significant age-differences were noted for HEB,HCM and Mixed. Of 355 patients with acute viral hepatitis, 43.94% had a history of contact, and 36.62% a history of injection.