A deep learning based holistic diagnosis system for immunohistochemistry interpretation and molecular subtyping

BACKGROUND

Breast cancer in different molecular subtypes, which is determined by the overexpression rates of human epidermal growth factor receptor 2 (HER2), estrogen receptor (ER), progesterone receptor (PR), and Ki67, exhibit distinct symptom characteristics and sensitivity to different treatment. The immunohistochemical method, one of the most common detecting tools for tumour markers, is heavily relied on artificial judgment and in clinical practice, with an inherent limitation in interpreting stability and operating efficiency. Here, a holistic intelligent breast tumour diagnosis system has been developed for tumour-markeromic analysis, combining the automatic interpretation and clinical suggestion.

METHODS

The holistic intelligent breast tumour diagnosis system included two main modules. The interpreting modules were constructed based on convolutional neural network, for comprehensively extracting and analyzing the multi-features of immunostaining. Referring to the clinical classification criteria, the interpreting results were encoded in a low-dimensional feature representation in the subtyping module, to efficiently output a holistic detecting result of the critical tumour-markeromic with diagnosis suggestions on molecular subtypes.

RESULTS

The overexpression rates of HER2, ER, PR, and Ki67, as well as an effective determination of molecular subtypes were successfully obtained by this diagnosis system, with an average sensitivity of 97.6 % and an average specificity of 96.1 %, among those, the sensitivity and specificity for interpreting HER2 were up to 99.8 % and 96.9 %.

CONCLUSION

The holistic intelligent breast tumour diagnosis system shows improved performance in the interpretation of immunohistochemical images over pathologist-level, which can be expected to overcome the limitations of conventional manual interpretation in efficiency, precision, and repeatability.

A pH-Mediated Highly Selective System Enabling Simultaneous Analysis of Circulating RNAs Carried by Extracellular Vesicles and Lipoproteins

Extracellular vesicles (EVs) and lipoproteins (LPPs) serve as important carriers of circulating miRNAs in peripheral blood, offering immense potential for disease diagnosis and therapeutic interventions. Due to their shared physicochemical attributes, EVs and LPPs are frequently coisolated, potentially leading to misunderstandings regarding their distinct functional roles in physiological and pathological processes. Here, we report a highly selective magnetic system based on the pH-mediated affinity displayed by cibacron blue (CB) toward EVs and LPPs, enabling successful separation and collection of these two nanoparticles without cross-contamination for subsequent circulating RNA analysis. First, we found that CB-modified magnetic beads (CBMBs) exhibit a strong affinity toward LPP particles while displaying little interaction with EVs in standard samples under physiological pH conditions. We further demonstrate that the affinity between CB molecules and bionanoparticles in plasma samples is highly pH-dependent. Specifically, CBMBs show affinities for both LPP and EV particles under neutral and acidic conditions. However, at basic pH levels, CB molecules selectively bind only to LPP particles. Consequently, the remaining EV particles present in plasma are subsequently isolated by using titanium dioxide-modified beads (TiMBs) through phospholipid affinity. The simultaneous analysis of the transcriptomic contents of EV and LPP reveals clear differences in their small RNA profiles, with the differentially expressed RNAs reflecting distinct biological processes. Significantly, in a proof-of-concept study, we successfully demonstrated a strong correlation between miRNAs carried by both EV and LPP particles with the occurrence of ocular neovascularization during the progression of diabetic retinopathy. The involved miRNAs may serve as potential biomarkers for DR diagnostics and severity classification. To sum up, this pH-mediated separation system is not only user-friendly but also highly compatible, rendering it a potent tool for probing the molecular compositions, biomarkers, and underlying biological mechanisms of EVs and LPPs.

Quantitative metabolic analysis of plasma extracellular vesicles for the diagnosis of severe acute pancreatitis

BACKGROUND

Severe acute pancreatitis (SAP) is the most common gastrointestinal disease and is associated with unpredictable seizures and high mortality rates. Despite improvements in the treatment of acute pancreatitis, the timely and accurate diagnosis of SAP remains highly challenging. Previous research has shown that extracellular vesicles (EVs) in the plasma have significant potential for the diagnosis of SAP since the pancreas can release EVs that carry pathological information into the peripheral blood in the very early stages of the disease. However, we know very little about the metabolites of EVs that might play a role in the diagnosis of SAP.

METHODS

Here, we performed quantitative metabolomic analyses to investigate the metabolite profiles of EVs isolated from SAP plasma. We also determined the metabolic differences of EVs when compared between healthy controls, patients with SAP, and those with mild acute pancreatitis (MAP).

RESULTS

A total of 313 metabolites were detected, mainly including organic acids, amino acids, fatty acids, and bile acids. The results showed that the metabolic composition of EVs derived from SAP and MAP was significantly different from those derived from healthy controls and identified specific differences between EVs derived from patients with SAP and MAP. On this basis, we identified four biomarkers from plasma EVs for SAP detection, including eicosatrienoic acid (C20:3), thiamine triphosphate, 2-Acetylfuran, and cis-Citral. The area under the curve (AUC) was greater than 0.95 for both discovery (n = 30) and validation (n = 70) sets.

CONCLUSIONS

Our data indicate that metabolic profiling analysis of plasma EVs and the screening of potential biomarkers are of significant potential for improving the early diagnosis and severity differentiation of acute pancreatitis.

Artificial Intelligence-Aided Multiple Tumor Detection Method Based on Immunohistochemistry-Enhanced Dark-Field Imaging

The immunohistochemical method serves as one of the most practical tools in clinical cancer detection and thus has great application value to overcome the existing limits of the conventional method and further improve the detecting efficiency and sensitivity. This study employed 3,3'-diaminobenzidine (DAB), a conventional color indicator for immunohistochemistry, as a novel high-sensitive scattering reagent to provide a multidimensional image signal varying with the overexpression rate of tumor markers. Based on the scattering properties of DAB aggregates, an efficient and robust artificial intelligence-aided immunohistochemical method based on dark-field imaging has been established, with improvement in both the imaging quality and interpretation efficiency in comparison with the conventional manual-operated immunohistochemical method. Referencing the diagnosis from three independent pathologists, this method succeeded in detecting HER2 overexpressed breast tumors with a sensitivity of 95.2% and a specificity of 100.0%; meanwhile, it was found to be applicable for non-small-cell lung tumors and malignant lymphoma as well. As demonstrated, this study provided an effective and reliable means for making diagnostic suggestions, which exhibited great potential in multiple tumor pathological detection at low cost.

Metabolomic analysis of exosomal-markers in esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma (ESCC) is a worldwide malignancy with high mortality rates and poor prognosis due to the lack of effective biomarkers for early detection. Exosomes have been extensively explored as attractive biomarkers for cancer diagnosis and treatment. However, little is known about exosome metabolomics and their roles in ESCC. Here, we performed a targeted metabolomic analysis of plasma exosomes and identified 196 metabolites, mainly including lipid fatty acids, benzene, amino acids, organic acids, carbohydrates and fatty acyls. We systematically compared metabolome patterns of exosomes via machine learning from patients with recrudescence and patients without recrudescence and demonstrated a marker set consisting of 3'-UMP, palmitoleic acid, palmitaldehyde, and isobutyl decanoate for predicting ESCC recurrence with an AUC of 98%. These metabolome signatures of exosomes retained a high absolute fold change value at all ESCC stages and were very likely associated with cancer metabolism, which could be potentially applied as novel biomarkers for diagnosis and prognosis of ESCC.

Target antifungal peptides of immune signalling pathways in silkworm, Bombyx mori, against Beauveria bassiana

Antifungal innate immunity is an important defence used by insects against entomogenous fungi. However, the downstream target antifungal peptides of different immune signalling pathways are unknown. We found that the Toll, Janus kinase/signal transducer and activator of transcription (Jak/STAT) and Immunodeficiency (IMD) signalling pathways in the silkworm, Bombyx mori, can be activated by Beauveria bassiana. Inhibition of the Toll, IMD and Jak/STAT signalling pathways reduced the antifungal activities of silkworm haemolymph. We verified the target antifungal peptides of different immune signalling pathways. The expression patterns of five anti-fungal peptide genes in silkworm larvae and BmN cells were detected after blocking or over-expressing the immune signalling pathways. The Toll signalling pathways mediated the expression of Bmcecropin A, Bmattacin 1 and Bmgloverin 2; IMD signalling pathways mediated Bmenbocin 1, Bmgloverin 2 and Bmattacin 1; Jak/STAT signalling pathways mediated Bmstorage protein 30K-19G1 (Bmsp 1), Bmattacin 1 and Bmcecropin A. These data indicated that anti-microbial peptide genes in B. mori evolved through expansion and selection of existing genes to adapt to the challenge of invasive microorganisms such as fungi. This information provides insight into the antifungal immune responses in B. mori and aids understanding of insect immune regulation mechanisms.

Antibody-Oriented Strategy and Mechanism for the Preparation of Fluorescent Nanoprobes for Fast and Sensitive Immunodetection

Nanoprobes have been widely used in biomedical engineering. However, antibodies are generally conjugated onto nanoparticles disorderly, which reduces their antigen recognition ability. The existing antibody orientation approaches are usually complex. Here, we developed and demonstrated a simple antibody-oriented strategy for the lateral flow immunoassay of cardiac troponin I by conjugating antibodies onto polystyrene nanospheres at the optimal pH. The binding amount and orientation of antibodies as well as the detection sensitivity were significantly improved. Although pH regulation is commonly used to optimize antibody conjugation, this paper illustrates the mechanism of its antibody orientation enhancement ability for the first time and reveals the important influences of the density, the charge distribution and hydrophilicity of the antibody, the control of the velocities of physical adsorption and chemical coupling, and other factors on antibody orientation. It is of great significance to understand and regulate antibody conjugation on the surface of micro- or nanospheres to construct high-performance probes for in vitro diagnosis applications.

A Rapid Test Strip for Diagnosing Glycosylated Hemoglobin (HbA1c) Based on Fluorescent Affinity Immunochromatography

In this research, we developed a rapid and easy-to-operate point-of-care testing (POCT) strip based on fluorescent affinity immunochromatography to quantitatively determine HbA1c concentrations in whole blood. This assay, based on a sandwich method performed on test strips, effectively utilized the principle of an affinity chromatography column, which was commonly used in the detection of HbA1c, and the technology of traditional fluorescence immunochromatographic test strips (FICTS) were combined. In our test strips, the test line of traditional FICTS was transformed into the region of affinity chromatography, while improving the linearity and reducing the interference of the precursor of HbA1c and hemoglobin variants. The test strips could quantitatively detect HbA1c over a wide range (3 - 13.8%) with excellent linearity (R² > 0.99), and the assay accuracy was demonstrated by comparing with high-performance liquid chromatography (HPLC) (R² > 0.95). The simple, rapid, effective and quantitative strips will provide a novel method for the detection of HbA1c in clinical diagnosis.

Fluorescent Nanoprobes with Oriented Modified Antibodies to Improve Lateral Flow Immunoassay of Cardiac Troponin I

Performance of nanoprobes can often determine the detection level of Lateral immunochromatography. Traditional probes were limited by the quantity and orientation of antibodies, immune activity of the Fab region or binding strength between protein and substrate. This study developed a new efficient and robust technology to construct fluorescent nanoprobes with oriented modified antibodies, based on specific binding of the Fc region of antibody with streptococcal protein G (SPG) on the surface of polystyrene microspheres (MS) and subsequent covalent cross-linking at binding sites to firm them. Lateral flow immunoassay using these probes was applied for the detection of cardiac troponin I (cTnI). The significantly improved detection sensitivity demonstrated that antibody orientation on MS surfaces effectively enhanced immunological activities of probes compared with random immobilizing methods. Furthermore, performance evaluation results of lateral flow test strips met clinical requirements perfectly, including limit of detection (0.032 ng/mL), linearity ( R > 0.99), repeatability (CV < 10%), correlation ( R > 0.99), and heat aging stability. This research also employed heterophilic blocking reagent (HBR) to actively block redundant binding sites of SPG for the first time in order to eliminate false positive interferences, improving the sensitivity and precision of test results further.

Peroxidase-Like Activity of Gold Nanoparticles and Their Gold Staining Enhanced ELISA Application

We found that the peroxidase-like activity of gold nanoparticles (GNPs) followed the Michaelis-Menten kinetic model and was dependent on environmental pH and temperature, which was very similar to natural Horseradish Peroxidase (HRP). However, unlike HRP, which needs a lower H2O2 concentration with a very narrow range to reach a maximum reaction rate and avoid enzyme poisoning, GNPs have very high activity, even at an H2O2 concentration two orders of magnitude higher than HRP. It was demonstrated that H2O2 treatment could enhance the peroxidase-like activity of GNPs, resulting thus in the activity increase in a circular catalytic reaction by the reduplicative use of GNPs. It was also found that the peroxidase-like activity of GNPs responded sensitively to nanoparticle size and surface modifications. When used in an immunoassay, GNPs were generally conjugated with antibody and blocked with hydrophilic macromolecules to construct a nanoprobe. This strongly reduced the peroxidase-like activity and detection sensitivity of GNPs, therefore, restricting their use as peroxidase mimetics. We presented a novel strategy that combined the nanoprobes with gold staining to expose fresh catalytic gold surfaces and obtained a great increase in detection sensitivity.

Enzyme catalysis enhanced dark-field imaging as a novel immunohistochemical method

Conventional immunohistochemistry is limited to subjective judgment based on human experience and thus it is clinically required to develop a quantitative immunohistochemical detection. 3,3'-Diaminobenzidin (DAB) aggregates, a type of staining product formed by conventional immunohistochemistry, were found to have a special optical property of dark-field imaging for the first time, and the mechanism was explored. On this basis, a novel immunohistochemical method based on dark-field imaging for detecting HER2 overexpressed in breast cancer was established, and the quantitative analysis standard and relevant software for measuring the scattering intensity was developed. In order to achieve a more sensitive detection, the HRP (horseradish peroxidase)-labeled secondary antibodies conjugated gold nanoparticles were constructed as nanoprobes to load more HRP enzymes, resulting in an enhanced DAB deposition as a dark-field label. Simultaneously, gold nanoparticles also act as a synergistically enhanced agent due to their mimicry of enzyme catalysis and dark-field scattering properties.

Pyrrolidine dithiocarbamate attenuates paraquat-induced acute pulmonary poisoning in vivo via transforming growth factor β1 and nuclear factor κB pathway interaction

Paraquat (PQ) exposure could cause pulmonary fibrosis. The aim of this study was to investigate the protective effect of pyrrolidine dithiocarbamate (PDTC) in an acute PQ poison model. One hundred and forty-four Sprague Dawley rats were equally divided into three experimental groups: control group, PQ group, and PQ + PDTC group. At days 1, 3, 7, 14, 28, and 56 of treatment, the serum levels of transforming growth factor β1 (TGF-β1), the levels of hydroxyproline, the protein expression of nuclear factor κB (NF-κB) pathway, and histopathological change in lung tissue were assessed. The survival rate of rats treated with PQ + PDTC was increased compared with that of rats treated only with PQ (p < 0.05), and the occurrence of pathological changes was dramatically attenuated in the PQ + PDTC group. The serum levels of TGF-β1 and the hydroxyproline levels in the PQ group were significantly increased in a time-dependent manner compared with those in the control and PQ + PDTC groups on days 7, 14, 28, and 56 (p < 0.05). Additionally, the protein levels of NF-κB proteins p65, inhibitor of κB (IκB) kinase (IKKβ, and IκB-α were significantly downregulated in the PQ + PDTC group as determined by array analysis. The present findings suggest that overexpression of TGF-β1 may play an important role in PQ-induced lung injury and that PDTC, a strong NF-κB inhibitor, can rescue PQ-induced pulmonary fibrosis by influencing the protein expression of NF-κB pathway.

Rituximab-Au nanoprobes for simultaneous dark-field imaging and DAB staining of CD20 over-expressed on Raji cells

A novel dual-modal cell immunodetection method based on both dark-field imaging and catalysis functions of gold nanoparticles has been established, where the Rituximab-Au conjugates were used as nanoprobes to label and image specifically the CD20 overexpressed on the surface of malignant lymphoma cells of Raji with high affinity.

Structural, electrical and optical properties of Mg-doped CuAlO2 films by pulsed laser deposition

P-type Mg doped CuAlO₂ films with high crystallinity are prepared by pulsed laser deposition followed by annealing, and exhibit enhanced conductivity and tunable optical band gaps.

A novel mutation in CRYBB2 responsible for inherited coronary cataract

PURPOSE

To study the molecular pathogenesis of a Chinese family with coronary form of cataract.

METHODS

One Chinese three-generation family with inherited coronary cataract phenotype was recruited. Five affected and seven unaffected family members attended our study. Genome-wide linkage analysis was applied to map the disease loci, and two candidate genes from a locus on chromosome 1 and a locus on chromosome 22 were sequenced for mutation identification. Software at the Expasy proteomics server was utilized to predict the mutation effect on proteins.

RESULTS

Whole genome linkage analysis indicated some regions on chromosome 1, 10, and 22, with LOD score values greater than 1. Within these loci, the GJA8 and CRYBB2 genes, located in the two loci with the highest LOD score of 1.51 on chromosomes 1 and 22, respectively, were sequenced. A novel mutation c.92C>G in exon 2 of CRYBB2 causing S31W was identified in all five patients. It was not found in 95 unrelated controls. This missense sequence alteration likely enhanced the local solubility. Around the mutation site, a lipocalin signature motif was predicted by ScanProsite.

CONCLUSIONS

A novel disease-causing mutation S31W in CRYBB2 was identified in a Chinese cataract family. It is the first reported mutation for coronary cataract. Functional characterization should be carried out to evaluate the biological effects of this mutant.

An assessment of exposure indices in computed radiography for the posterior–anterior chest and the lateral lumbar spine

Studies have indicated that computed radiography (CR) can increase radiation dose to the patient, leading to potential biological effects. Although manufacturers have set parameters to safeguard against overexposure, it is unclear whether these are being used by radiographers or if their recommended values are consistent with the ALARA principle. The research aims are to investigate (i) whether radiographers are producing images with exposure indices within the manufacturers recommended range (MRR); (ii) the phenomenon of exposure creep, and (iii) the relationship between exposure indices (EIs) and radiation dose. A retrospective analysis of exposure indices over an 18-month period for the posteroanterior (PA) chest and lateral (LAT) lumbar spine at two centres using Kodak 800 and 850 CR systems was conducted. A phantom study was performed to assess the relationship between EI and entrance surface dose (ESD) for fixed and varying tube potentials. Kodak recommends that images have EIs between 1700 and 1900. Thirty percent of LAT lumbar spine examinations at hospital B and 38% of PA chest examinations at hospital A were produced with EIs below 1700. In the phantom study, when using a varied tube potential (70-125 kVp) and maintaining a constant EI of 1550, ESD was reduced by 56%. All clinical and phantom images were assessed to be of a diagnostic quality. The retrospective results indicate that there is a potential to reduce the MRR and optimize patient dose. There is also evidence to suggest that EI is not a reliable indicator of patient dose. The authors recommend that staff training is essential on these newer systems.

The tuberous sclerosis 2 gene product can localize to nuclei in a phosphorylation-dependent manner

The tuberous sclerosis 2 (TSC2) gene has been genetically mapped to a disease characterized by abnormal cell proliferation that results in the production of tumorous lesions in a variety of tissues. The molecular mechanism for TSC2 mediation of tuberous sclerosis is unclear but it appears to be related to its ability to cytoplasmically interact with a second gene, TSC1, mapping to the disease. These proteins are linked to constraints on cell cycle signaling pathways and therefore envisioned to function as tumor suppressor genes. In previous studies we have demonstrated TSC2 associations with steroid receptor family members and modulation of their gene expression capabilities. Here we provide evidence for TSC2 translocation to the nucleus and a possible role for phosphorylation in both TSC2 translocation and TSC2 modulation of steroid receptor-mediated transcription.

Stimulation of antiviral antibody response in SHIV-IIIB-infected macaques

Three macaques infected with SHIV-IIIB and expressing the shared 1F7-idiotypic marker on antibodies against HIV-1 gp120, were injected intravenously with 1F7 monoclonal antibodies (MoAb). As controls, a SHIV-IIIB-infected macaque was injected with a HIV-unrelated mouse monoclonal isotype antibody (TEPC-183) and two healthy, noninfected macaques were injected with MoAb 1F7. 1F7-id-expressing antibodies against gp120-IIIB decreased in two of the three MoAb 1F7-treated macaques and then rebounded. Importantly, antibodies binding to envelope proteins of heterologous HIV-1 strains MN, CM, and SF2, which were low or not detectable before the MoAb 1F7 treatment, increased rapidly following MoAb inoculations in all three 1F7 MoAb treated macaques, but not in the macaque injected with control MoAb TEPC-183. Newly arising antibodies reacting with heterologous virus, i.e. HIV-1 gp120-MN, SF2, and CM did not express 1F7-id. Surprisingly, significant increases of antibodies were also observed in the 1F7-inoculated macaques' antibodies directed to non-HIV antigens (DNP, peptides and BSA). The noninfected control animals did not produce antibodies to these antigens despite MoAb 1F7 treatment. These data show that the MoAb 1F7 injections of chronically SHIV-IIIB-infected macaques resulted in idiotype-specific clonal suppression with broadening the antibody response to HIV envelope proteins.

Chemical engineering of cell penetrating antibodies

Antibodies, being exquisitely specific tools in biology, are routinely used to detect and identify intra-cellular structures. However, current intra-cellular application of antibodies requires that the membrane be rendered leaky, resulting in the death of cells. Here, we present a novel method to allow antibodies to penetrate the cellular membrane of living cells without affecting cell viability. A peptide (MTS, membrane transport sequence) that facilitates transport across membranes has been site-specifically attached to antibodies. MTS-antibodies enter the living cells in culture and can be detected by immunofluorescence and ELISA after extraction. Cellular structures are visualized in living cells using a specific MTS-antibody. Antibodies with membrane penetrating properties can become an important tool for the study of intra-cellular processes in living cells. Furthermore, such membrane penetrating antibodies can be used to selectively stimulate or suppress functions of the cellular machinery.

Site-specific photobiotinylation of antibodies, light chains, and immunoglobulin fragments

The high affinity of biotin for avidin has been exploited for many antibody-based assays. This requires that biotin is covalently conjugated to the antibody molecule. Several chemically reactive biotinylation reagents are commercially available. Except for the attachment via sulfhydryl groups in the immunoglobulin (Ig) molecule, these reagents attach biotin randomly to various amino acid side chains. Although non-site-specific modification of antibodies does not interfere in most immunoassays, specific application and sensitive antibodies would benefit from site-specific biotinylation. Here we describe an affinity biotinylation technique based on a photoreactive biotin reagent. The design of this reaction was possible from the discovery of a conserved binding site in the variable Ig domain for nucleotides and nucleosides. The described photoaffinity biotinylation offers the advantages of ease, convenience, and production of a reproducible and defined biotinylated antibody preparation.

[The expression of connexin 43 and desmin in viral myocarditis]

OBJECTIVE

To study the cytobiological basis of constriction dysfunction and arrhythmia in cardiac muscle cells with viral myocarditis.

METHODS

The expression of connexin 43 and desmin in cardiac muscle cells of mice with experimental viral myocarditis was determined by immunohistochemistry.

RESULTS

In normal mice, connexin 43 and desmin are located in the intercalated disks of cardiac muscle, and the latter also revealed a positive immunoreactivity in the cross striations of sarcomeres. In viral myocarditis, the expression of both became much weakened, can even become negative.

CONCLUSION

In myocarditis, expression of connexin 43 and desmin in the involved cardiac muscle cells was inhibited, resulting in dysfunction of gap junctional communication and arrhythmia.

Management of parapneumonic collections in infants and children

BACKGROUND/PURPOSE

Video-assisted thoracoscopic surgery (VATS) has a recognized role in treatment of empyema thoracis. The purpose of this report is to show the value of initial VATS as the primary treatment of parapneumonic collections.

METHODS

A retrospective review was done of 139 children who required surgical consultation for parapneumonic collections between January 1992 and July 1998. Management options were (M1) thoracentesis, chest tube drainage, or fibrinolytic therapy and delayed thoracotomy for unresolved collections; (M2) thoracentesis, chest tube drainage, fibrinolytic therapy with delayed VATS if the child remained ill; or (M3) primary VATS. Comparative data included age, duration of prehospital illness, oxygen requirements, white blood cell count, bacterial culture results, number of procedures performed per patient, duration of chest tube drainage, complications, and length of stay. Kruskal-Wallis 1-way analysis was used, with significance at P less than .05.

RESULTS

A total of 60 children were treated by M1, 38 by M2, and 41 by M3. Age, duration of prehospital illness, oxygen requirements, white blood cell count, bacterial culture results, and complication rates were comparable. The median length of stay was 12 days for M1, 11 days for M2, and 7 days for M3, with M3 significantly shorter at P<.001. The number of procedures was a median of 2 in M1, 2 in M2, and 1 in M3, with M3 significantly fewer at P<.001. Duration of chest tube drainage was a median 5 days for M1 and 3 days for M2 and M3, with M1 significantly longer at P<.001. There were 9 thoracotomies in the M1 group, 3 in the M2 group, and none in the M3 group. One child in M3 required a second VATS.

CONCLUSIONS

Primary VATS has significantly decreased the number of procedures, duration of chest tube drainage and length of stay for children with parapneumonic effusions. Primary VATS appears to be of value in management of bacterial pneumonia with effusion.

[Correlation of expression of connexin 43 and cardiomyocyte hypertrophy]

OBJECTIVE

To study the relationship between the expression of connexin 43 and cardiomyocytes hypertrophy.

METHODS

Cardiomyocytes were isolated from newborn Wistar rats. Norepinephrine (NE) or phenylephrine (PE) were added into the media to induce myocyte hypertrophy. Immunohistochemistry methods were used to identify the expression of connexin 43, proliferating cell nuclear antigen (PCNA) and cycline dependent kinases (cdc-2). The amount of connexin 43 expression was detected by computer imaging analysis system MIPS.

RESULTS

In the groups which had PE or NE added, the myocytes expressed lower connexin 43 and higher PCNA levels than the control group's. But the expression of cdc-2 was unchanged.

CONCLUSION

The reduced expression of connexin 43 was related to its entrance into S phase of the cell cycle. This may explain the mechanism of cardiomyocyte hypertrophy.

Pathologic changes, mechanisms and diagnosis in renal bone disease

OBJECTIVE

To investigate the incidence rate, pathologic changes, mechanisms and diagnostic methods in renal bone disease.

METHODS

The blood levels of carboxyterminal parpthyriod hormone (C-PTH), 1,25(OH)2D3, calcium and phosphate, aluminum in serum and bone tissue were measured. The bone biopsy and bone scan with 99m technetium methylene diphosphonate (99mTC-MDP) were performed in 51 uremic patients.

RESULTS

One hundred per cent of the patients had varying degree of pathologic changes in bone, in which 50.9% of the patients presented high-turnover bone disease, 7.8% of the patients presented low-turnover bone disease and 41.8% of the patients had mixed-type bone disease. The levels of serum C-PTH were predominently high in high-turnover bone disease while the levels of serum 1,25(OH)2D3 were significantly decreased in low-turnover bone disease. There was a high positive rate for the diagnosis of renal bone disease by bone scan with 99mTC-MDP.

CONCLUSIONS

The examination of bone pathology is the most valuable method for the diagnosis of renal bone disease. Bone scan with 99mTC-MDP has reference value when clinical conditions do not allow to make bone biopsy.

[Purification of recombinant erythropoietin by reversed-phase high performance liquid chromatography (RP-HPLC)]

Recombinant erythropoietin is a glycoprotein which is strongly hydrophobic. We purified recombinant erythropoietin by RP-HPLC. The results showed that 30 nm Spherisorb C4 reversed-phase column and acetonitrile-TFA mobile phase with gradient elution, could readily isolate recombinant erythropoietin from crude samples with high speed and efficiency. Erythropoietin could be eluted at the concentration of about 50% acetonitrile with appropriate sample purity and elution gradient. When RP-HPLC is used as a final step of purification, the purity of sample should be at least 60%. The purity of the product tested by SDS-PAGE was nearly 100%. And the specific activity of the product was about 1.96 x 10(3) IU/g protein.

Enhanced molecular mimicry of CEA using photoaffinity crosslinked C3d peptide

Antigen mimicry of using anti-idiotypic antibodies for use as cancer vaccines has been disappointing due to the weak immunogenicity of immunoglobulin variable domains. To enhance the immunogenicity of an anti-idiotype vaccine we incorporated a molecular adjuvant peptide into the antibody. The peptide is derived from the C3d region known to bind CR2 receptors on B-cells. A photoreactive peptide is synthesized that affinity-labels a single site in the antibody variable domain. The molecular adjuvant peptide is crosslinked to the anti-idiotype mimetic by chemical means without modifying other sites on the antibody. The C3d-conjugated anti-idiotype antibody induces a strong idiotype and antigen-specific response in mice.

[Relationship between microsurgical tubal reversal and ectopic pregnancy]

OBJECTIVE

To study the correlation between microsurgical tubal reversal after tubal sterilization and ectopic pregnancy.

METHODS

1029 women who underwent microsurgical tubal reversal were followed up. The causes of ectopic pregnancy were analysed and discussed.

RESULTS

960 intrauterine pregnanciess and 12 ectopic pregnancies occurred. The 12 ectopic pregnancies were all tubal ones, among which 2 had intrauterine pregnancies. The rate of ectopic pregnancy in the 1029 women was 1.17%, and in the pregnant cases was 1.23%. The ratio of intrauterine pregnancy to ectopic pregnancy was 1:80. The rates of ectopic pregnancy in the 1st, 2nd year and 2 years later after tubal reversal were not significantly different respectively among the tubal reversal and among the pregnant cases. The rates of ectopic pregnancy in the 1st and 2nd 6 months after tubal reversal were not statistically different. The early tubal hydrapertubation could only increase the chance of ectopic pregnancy. The sterilization method, reversal mode, and interval between sterilization and reversal were not related to the ectopic pegnancy.

CONCLUSION

When the lesion in the sterilized position is completely removed, the sutures being through the tubal mucosa and the early tubal hydrapertubation not carried out, the chance of ectopic pregnancy can not be increased after tubal reversal. The contraception 6 months after tubal reversal is not related to ectopic pregnancy.

Site-specific photobiotinylation of immunoglobulins, fragments and light chain dimers

Herein we report a new method to rapidly photoinsert biotin into a specific and highly conserved site on the Ig structure using a mild photochemical activation step. This site resides in the Fv fragment and involves invariant residues which provide base stacking interactions to the purine ring of ATP (Rajagopalan et al. (1996) Proc. Natl. Acad. Sci. USA 93, 6019-6024). Biotin was coupled to either the phosphate or the ribose of the 8-azidopurine nucleotide or nucleoside photoaffinity probe and shown to insert into the affinity site efficiently. Several monoclonal and polyclonal antibodies, as well as enzymatic and recombinant antibody fragments and light chain dimers were photoaffinity biotinylated and used in ELISA, FACS and Western blots. The selectivity of this site-specific biotinylation method also allows for biotinylation of antibodies in culture supernatants and immune sera without prior purification. Because the biotinylation takes place under physiological conditions and within a short time period, photobiotinylation would be the preferred method for antibodies which are easily damaged by classical non-site specific random biotinylation chemistry.

Antibody-mediated gene delivery for B-cell lymphoma in vitro

The targeted introduction of therapeutic genes into malignant cells based on receptor mediated endocytosis of ligand-DNA conjugates recently was established as a transfection system and provides a promising strategy for cancer therapy. Antiidiotype antibodies could be of particular interest for this approach because their immunoglobulin receptor idiotypes represent highly specific tumor markers. Their safe and specific applicability in vivo, alone or as immunotoxins, has been proven in clinical trials for passive immunotherapy and vaccination strategies. For these reasons we have explored the utility of antiidiotype antibodies for gene delivery systems using the reporter genes beta-galactosidase and luciferase. Two monoclonal antibodies, SIC5 and 5D10, specific for B-lymphoma cell lines, which represent models for murine plasmacytoma (38C13) and human non-Hodgkin's lymphoma (SU-DHL-4) have been covalently linked to polylysine via the heterobifunctional cross-linker SPDP. Highly efficient uptake and internalization of the immunoconjugates have been shown by fluorescence microscopy and fluorescence-activated cell sorting (FACS) analysis. Successful transfections have been shown at the RNA and the reporter gene level (beta-galactosidase, luciferase) using different promoter/enhancer systems. Beta-galactosidase activity was detected by flow cytometry (FACS-gal) analysis for both cell lines, and SU-DHL-4 cells showed significant luciferase activity.

Avoiding serious complications in laparoscopic cholecystectomy--lessons learned from an experience of 2428 cases

Over a three-and-a-half year period, we performed 2428 cases of laparoscopic cholecystectomy (LC) and encountered 11 cases of serious procedure-related complications, including bile duct injuries in 4 patients, postoperative bleeding requiring laparotomy and haemostasis in 3 patients, bile leakage from the cystic duct stump, jejunal injury related to puncture, intraoperative injury to the duodenum and subdiaphragmatic abscess in 1 patient each respectively. Six patients required re-hospitalisation including 2 patients with pancreatitis, 1 patient with Ascaris cholangitis, 1 patient with residual stone of the common bile duct (CBD) after laparoscopic CBD exploration, 1 patient with a stone in the CBD after LC, and 1 patient with bile leakage from the cystic duct stump and peritonitis. Of the 2428 patients treated, there was only 1 operative mortality. This patient developed frequent episodes of supraventricular tachycardia. She was found to have pnuemonia on the 21st postoperative day and she died. Apart from this, 1 other patient was found to have primary cancer of the liver 1 month after LC. Based on our experience, we think that LC is safe for patients with benign disease of the gallbladder.

[Distribution and quantification of oxidative low density lipoprotein in the development of atherosclerotic lesions of human aorta]

A total of 35 human aorta specimens obtained within 12 hours postmortem were collected. The distribution pattern and quantity of LDL and ox-LDL in atherosclerotic lesions of varying severity and the relationship with aorta cells were studied by immunohistochemical techniques and computorized image processing. The results showed that the staining pattern with anti-ox-LDL and antibodies to apoB was similar; in fatty steaks, the staining for ox-LDL was predominantly cell-associated in macrophages derived foam cells, in the late lesions, its pattern shifted to smooth muscle cells and extra-cellular matrix staining, there was also more apoB in fibrofatty plaques and atheromatous plaques than in fatty streaks, but no significant difference was found between the two stages of plaques. The quantity of Cu(2+)-ox-LDL significantly increased with the development of AS. There was more LDL than ox-LDL in fatty streaks, but in the late plaques, there was significantly more ox-LDL than LDL.

Genetic linkage of autosomal dominant juvenile glaucoma to 1q21-q31 in three affected pedigrees

Glaucoma is a common disorder that results in irreversible damage to the optic nerve, causing absolute blindness. In most cases, the optic nerve is damaged by an elevation of the intraocular pressure that is the result of an abnormality in the normal drainage function of the trabecular meshwork. A family history of glaucoma is an important risk factor for the disease, suggesting that genetic defects predisposing to this condition are likely. Three pedigrees segregating an autosomal dominant juvenile glaucoma demonstrated significant linkage to a group of closely spaced markers on chromosome 1. These results confirm the initial mapping of this disease and suggest that this region on chromosome 1 contains an important locus for juvenile glaucoma. We describe recombination events that improve the localization of the responsible gene, reducing the size of the candidate region from 30 to 12 cM.

[Immunoregulatory effects of monomer T4 from Tripterygium wilfordii hook. I. Immunoregulatory effects of T4 on NK activity of mouse splenocytes]

Effects of monomer T4 on NK activity of mouse splenocytes were determined both in vitro and in vivo by means of a classical I-UdR release assay. The results showed that monomer T4 exhibited dose-dependent double-regulatory inhibiting enhancing effects, ie, T4 of low dosage enhanced the percentage of NK cytotoxicity and LU numbers, while a high dosage showed dose-dependent inhibition. The double-regulatory effects of monomer T4 might be important for evaluation of the therapeutic effects of Tripterygium wilfordii Hook in future clinical practice.