[Comparison among different flushing media for intracoronary imaging with optical coherence tomography]

Objective: To explore the effects and safety of saline mixed 1∶1 with contrast medium (mixed medium) and pure heparinized saline as alternative media for optimal Optical Coherence Tomography (OCT) guided percutaneous coronary intervention (PCI). Methods: This single-center, prospective cohort study enrolled patients who underwent PCI with OCT guidance for chronic stable angina or acute coronary syndrome at the Department of Cardiology, the Second Hospital of Jilin University from October 2021 to August 2022. The target vessels were examined using OCT with three different flushing media at the same anatomical positions: contrast agent, mixed medium, and pure heparinized saline. An independent observer analyzed all imaging results and evaluated the lumen imaging quality, using the proportion of the clear imaging field (CIF%) as a quantitative measure for analysis. The average luminal diameter was compared among different flushing media. The study also assessed the image quality of the luminal anatomical structures, lesion pathologies, and stents. Results: A total of 105 patients were enrolled in the study, including 110 target vessels. The age of the enrolled patients was (60.5±8.4) years, with 60 male patients (57.1%). OCT examinations were successfully completed using all three media, and no related complications were observed in any groups. The three flushing media presented with the same image quality in terms of depicting the lumen anatomical structures, lesion characteristics, and stent-related features. The mixed medium group achieved a comparable CIF% to the contrast group with both right and left coronary arteries (right coronary 100.0% (100.0%, 100.0%) vs. 100.0% (100.0%, 100.0%), P>0.05; left coronary 100.0% (95.9%, 100.0%) vs. 100.0% (100.0%, 100.0%), P>0.05). While the saline group reached a comparable CIF% to the contrast group with right coronary arteries (100.0% (97.6%, 100.0%) vs. 100.0% (95.9%, 100.0%), P>0.05) but showed a significantly lower CIF% with left coronary arteries (84.9% (75.9%, 93.4%) vs. 100.0% (100.0%, 100.0%), P<0.05). For the average diameter of the coronary lumen, there was no statistically significant difference between the mixed medium group and the saline group compared to the contrast group with both right and left coronary arteries (P>0.05). Conclusions: A 1∶1 heparinized saline and contrast mixture can serve as a substitute flushing medium for OCT examination during PCI procedure. Pure saline can also yield good results in OCT examination of the right coronary artery, and both alternatives are safe for use as flushing medium in OCT imaging.

Metabolomics analysis of the nutraceutical diversity and physiological quality of Torreya yunnanensis seeds during cold storage

This study investigated how cold storage affects the nutraceutical diversity and physiological quality of Torreya yunnanensis seeds, using a widely targeted UPLC-MS/MS-based metabolomics analysis. The 373 identified metabolites were divided into nine categories: lipids, phenolic acids, amino acids and derivatives, organic acids, nucleotides, saccharides, vitamins and alcohols. Among them, 49 metabolites showed significant changes after 3 months of cold storage, affecting 28 metabolic pathways. The content of amino acid-related metabolites significantly increased, while the content of sugar-related metabolites decreased during storage. Notably, the content of proline acid, shikimic acid, α-linolenic acid and branched-chain amino acids showed significant changes, indicating their potential role in seed storage. This study deepens our understanding of the nutraceutical diversity and physiological quality of T. yunnanensis seeds during storage, providing insight for conservation efforts and habitat restoration.

Tributyrin supplementation in pasteurized waste milk: Effects on growth performance, health, and blood parameters of dairy calves

This study evaluated the effects of incremental tributyrin supplementation in pasteurized waste milk on growth performance, health, and blood metabolism of dairy calves before and after weaning. Forty-eight newborn female Holstein dairy calves (39.6 ± 2.75 kg; mean ± standard deviation) were blocked by age and randomly assigned to 3 treatments: pasteurized waste milk (1) without supplementation, (2) with 1 g/L of tributyrin products (unprotected solid powder; containing 35% tributyrin), or (3) with 2 g/L of tributyrin products. The calves were weaned on d 56 and were raised until d 77. Data were analyzed for the preweaning, postweaning, and overall periods. The results showed that starter intake and hay intake were not different among treatments in any period of the trial, but the crude protein intake tended to increase linearly with tributyrin supplementation during the overall period. Although tributyrin supplementation had no effects on body weight during preweaning and overall periods, body weight increased linearly with tributyrin supplementation postweaning. The average daily gain tended to increase linearly during postweaning and overall periods. No effects were observed on feed efficiency in any period. A positive linear relationship between body length and tributyrin supplementation was observed during the postweaning period, but no differences were found for the other body structural measurements in any period. The results of diarrhea showed that tributyrin concentration had a negative linear relationship with diarrhea frequency during preweaning and overall periods. The rectal temperature did not differ among treatments in any period, but a treatment × week effect for rectal body temperature was observed. For blood metabolism, tributyrin supplementation had no effects on insulin, growth hormone, total protein, albumin, or globulin. No differences were found in serum amyloid A concentration in any of the periods, yet haptoglobin concentration decreased linearly with increasing tributyrin concentration during postweaning and overall periods. Endothelin concentration showed a tendency to decrease linearly during preweaning and postweaning periods and decreased linearly with tributyrin supplementation during the overall period. An increasing tributyrin concentration was associated with a negative linear relationship with IL-1β concentration during the preweaning period, and no differences were found in the other periods. The concentration of IL-6 and tumor necrosis factor α were not different among treatments in any of the periods. These data suggest that increasing the concentration of tributyrin in pasteurized waste milk could increase growth performance and health of dairy calves, and incremental tributyrin supplementation could linearly reduce haptoglobin, endothelin, and IL-1β concentrations, indicating a positive effect of tributyrin on alleviating oxidative stress and inflammatory status of dairy calves. Calves fed pasteurized waste milk supplemented with tributyrin products (containing 35% tributyrin) at 2 g/L compared with 1 g/L of milk had more improved growth and health.

The inhibitory effects of cisplatin-radiation combination treatment on malignant osteosarcoma MG-63 cells and BRCA1-p53 pathways are more efficient than single treatments

The poor prognosis of patients with osteosarcoma remains a persistent problem, in particular for patients with unresectable tumors or metastasis. Therefore, combination of radiotherapy and chemotherapy has been considered for patients with metastasis or recurrence, patients unsuitable for surgery and patients refusing surgery. The present study aimed to investigate the effect of the combined treatment with cisplatin and radiation therapy on the biological characteristics of the osteosarcoma cell line MG-63 and the breast cancer 1 (BRCA1)-associated signaling pathways. Cell proliferation was determined using Cell Counting kit-8 assay, and cell apoptosis and cell cycle were assessed by flow cytometry. Cell migration was examined by Transwell assay. The mRNA and protein expression levels of candidate genes, including BRCA1 and p53, were determined by reverse transcription-quantitative PCR and western blotting, respectively. The results demonstrated that combined treatment with radiation and cisplatin significantly inhibited MG-63 cell proliferation compared with radiation or cisplatin treatment alone. Furthermore, radiation, cisplatin or the combined treatment with radiation and cisplatin increased the apoptosis rate of MG-63 cells, which resulted in G₂ phase arrest, and significantly decreased the migratory capacity of MG-63 cells. In addition, the apoptosis rate of MG-63 cells following combined radiation and cisplatin treatment was higher compared with the cisplatin group, but lower compared with the radiation group. Furthermore, combined treatment with radiation and cisplatin decreased the mRNA and protein expression levels of BRCA1 and p53. Additionally, combined treatment with radiation and cisplatin had a more potent inhibitory effect on p53 expression than on BRCA1 expression. In addition, combination of radiation and cisplatin had a higher inhibitory effect on Bax protein level and a higher inductive effect on Bcl-2 protein level compared with treatments with radiation and cisplatin alone. The results demonstrated that combined treatment of radiation and cisplatin exhibited superior therapeutic effects on osteosarcoma MG-63 cells compared with radiation or cisplatin treatment alone, which may be mediated by the BRCA1-p53 signaling pathway.

Asymptomatic left posterior mediastinal functional paraganglioma: A case report

RATIONALE

Paraganglioma refers to a set of neuroendocrine tumors derived from the chromaffin cells of the adrenal diplomatic ganglion. Paragangliomas can be classified as functional or nonfunctional based on the ability to synthesize and release catecholamines.

PATIENT CONCERNS

We report a 47-year-old man with a functional paraganglioma in the left posterior mediastinum and highlight the key elements of management of mediastinal paragangliomas.

DIAGNOSES

A left posterior mediastinal mass was found by computed tomography (CT) scan and Chest-enhanced CT. Preoperative ultrasound-guided biopsy suggested the possibility of a paraganglioma. A diagnosis of paraganglioma was established by immunohistochemistry.

INTERVENTIONS

The patient underwent single-stage resection of the lesion via left thoracotomy after preoperative oral α-adrenoceptor (phenoxybenzamine) therapy and intravenous fluid resuscitation for two weeks.

OUTCOMES

The postoperative period was uneventful. The patient exhibited no abnormal blood pressure or recurrence during the 12-month follow-up period.

LESSONS SUBSECTIONS AS PER STYLE

Pathological examination alone cannot determine whether it was a benign or malignant paraganglioma, which can be determined by pathological examination combined with distant metastasis. Long-term follow-up is required to assess the treatment effect.

Cisplatin as a Radiosensitizer in Clinical Practice: A Pilot Study

Fifty-four patients with Inoperable cancers were treated with a combination of cisplatin and radiotherapy from May 1984 to February 1989. Cisplatin was administered at a dose of 40 mg/week, for a total dose of 160-320 mg, during radiation therapy. In 4 cases with brain metastases, the cisplatin dose was 40 mg/m2. Cisplatin concentration in blood was measured using the flameless atomic absorption spectrophotometric method. Radiation therapy was delivered by a 6 MV X-ray or a cobalt-60 unit up to a total dose of 50-70 Gy. Among the 54 patients, 89% (48) responded to the treatment regimen; complete responses (CR) and partial responses (PR) were 56% and 33%, respectively. Six patients were stable in their disease. Among the 30 patients who had CR's, the 1-year survival rate was 88% (21/24). Two patients (7%) had local relapse. However, among PRs, the 1-year survival rate was 33% (4/12) and local failure (61%) (11/18). Objective tumor response was observed in 4 cases with brain metastasis, 2 of the 4 patients were alive for more than 6 months. Toxic effects were moderate and consisted of emesis and myelosuppression. Grade III bone marrow suppression amounted to 11%, and the interval of recovery was relatively long compared with that reported in the literature. Further prospective controlled studies are recommended.

MicroRNA-130a alleviates human coronary artery endothelial cell injury and inflammatory responses by targeting PTEN via activating PI3K/Akt/eNOS signaling pathway

Our study aims to investigate the roles of microRNA-130a (miR-130a) in human coronary artery endothelial cells (HCAECs) injury and inflammatory responses by targeting PTEN through the PI3K/Akt/eNOS signaling pathway. HCAECs were treated with 1.0 mmol/L homocysteine (HCY) and assigned into eight groups: the blank group, the negative control (NC) group, the miR-130a mimics group, the miR-130a inhibitors group, the si-PTEN group, the Wortmannin group, the miR-130a inhibitors + si-PTEN group and the miR-130a mimics + Wortmannin group. Luciferase reporter gene assay was used to validate the relationship between miR-130a and PTEN. The expressions of miR-130a, PTEN and PI3K/Akt/eNOS signaling pathway-related proteins were detected by qRT-PCR assay and Western blotting. MTT assay and Hoechst 33258 staining were adopted to testify cell growth and apoptosis. The NO kit assay was used to detect the NO release. ELISA was conducted to measure serum cytokine levels. Luciferase reporter gene assay confirmed the target relationship between miR-130a and PTEN. Compared with the blank and NC groups, the miR-130a mimics and si-PTEN groups showed significant increases in the expressions of PI3K/Akt/eNOS signaling pathway-related proteins, cell viability and the NO release, while serum cytokine levels and cell apoptosis were decreased; by contrast, an opposite trend was observed in miR-130a inhibitors and Wortmannin groups. However, no significant difference was found in the miR-130a inhibitors + si-PTEN and miR-130a mimics + Wortmannin groups when compared with the blank group. These results indicate that miR-130a could alleviate HCAECs injury and inflammatory responses by down-regulating PTEN and activating PI3K/Akt/eNOS signaling pathway.

Initial clinical experience of CrossBoss catheter for in-stent chronic total occlusion lesions: A case report

BACKGROUND

The CrossBoss coronary chronic total occlusion (CTO) crossing catheter has been demonstrated to have greatly improved the success rate of crossing CTO lesions, but there are no published data on its application for in-stent CTO lesions.

METHODS

In the current study, we retrospectively reviewed the clinical data of 8 patients with in-stent CTO lesions that were managed with the CrossBoss catheter and herein we report the efficacy and safety of the CrossBoss crossing and re-entry system for this clinically challenging condition.

RESULTS

The CrossBoss catheter was used for 8 patients with in-stent CTO lesions, which resulted in success in 6 cases and failure in 2 cases, with a 75% success rate. Of the 6 patients with successful treatment, 5 cases had the occlusive lesions crossed with the CrossBoss catheter through a proximal lumen-to-distal lumen approach, whereas the remaining case had his occlusive lesions penetrated by the CrossBoss catheter and the guidewire. Two cases failed in treatment as the CrossBoss catheter could not cross the occlusive lesions. The 6 cases with successful treatment included 3 cases with occlusive lesions in the left anterior descending artery, 1 case with occlusive lesions in the obtuse marginal branches, and 2 cases with occlusive lesions in the right coronary artery, and the 2 cases with failure in treatment had their occlusive lesions in the right coronary artery. In addition, patients with a higher Japan chronic total occlusion score were found to have a lower success rate of crossing the occlusive lesions. None of the patients developed complications.

CONCLUSION

Our study demonstrates that the CrossBoss catheter has a high success rate and is safe for in-stent CTOs and can be recommended for this rather clinically challenging condition.

Anti-apoptotic effect of microRNA-30b in early phase of rat myocardial ischemia-reperfusion injury model

This study aimed to investigate the effect of microRNA-30b (miR-30b) in rat myocardial ischemic-reperfusion (I/R) injury model. We randomly divided Sprague-Dawley (SD) rats (n = 80) into five groups: 1) control group; 2) miR-30b group; 3) sham-operated group; 4) I/R group, and 5) I/R+miR-30b group. Real-time quantitative polymerase chain reaction, immunohistochemical staining and Western blot analysis were conducted. TUNEL assay was employed for testing cardiomyocyte apoptosis. Our results showed that miR-30b levels were down-regulated in I/R group and I/R + miR-30b group compared with sham-operated group (both P < 0.05). However, miR-30b level in I/R + miR-30b group was higher than I/R group (P < 0.05). Markedly, the apoptotic rate in I/R group showed highest in I/R group (P < 0.05). Additionally, the results illustrated that protein levels of Bcl-2, Bax, and caspase-3 were at higher levels in ischemic regions in I/R group, comparing to sham-operated group (all P < 0.05), while Bcl-2/Bax was reduced (P < 0.05). Bcl-2 level and Bcl-2/Bax were obviously increased in I/R + miR-30b group by comparison with I/R group, and expression levels of Bax and caspase-3 were down-regulated (all P < 0.05). We also found that in I/R + miR-30b group, KRAS level was apparently lower and p-AKT level was higher by comparing with I/R group (both P < 0.05). Our study indicated that miR-30b overexpression had anti-apoptotic effect on early phase of rat myocardial ischemia injury model through targeting KRAS and activating the Ras/Akt pathway.

Fluoroscopically guided nose tube drainage of mediastinal abscesses in post-operative gastro-oesophageal anastomotic leakage

OBJECTIVE

The aim of this study was to retrospectively evaluate the technical success rates and clinical effectiveness of fluoroscopically guided nose tube drainage of mediastinal abscesses and a nasojejunum feeding tube in post-operative gastro-oesophageal anastomotic leakage (GEAL).

METHODS

From January 2006 to June 2011, 18 cases of post-operative GEAL with mediastinal abscesses after oesophagectomy with intrathoracic oesophagogastric anastomotic procedures for oesophageal and cardiac carcinoma were treated by insertion of a nose drainage tube and nasojejunum feeding tube under fluoroscopic guidance. We evaluated the feasibility of two-tube insertion to facilitate leakage site closure and complete resolution of the abscess, and the patients' nutritional benefit was also evaluated by checking the serum albumin level between pre- and post-enteral feeding via the feeding tube.

RESULTS

The two tubes were placed successfully under fluoroscopic guidance in 18 patients (100%). The procedure time for two-tube insertion ranged from 20 to 40 min (mean 30 min). 17 patients (94%) achieved leakage site closure after two-tube insertion and had a good tolerance of two tubes in the nasal cavity. The serum albumin level was significant, increased from pre-enteral feeding (2.49 ± 0.42 g dl(-1)) to the post-enteral feeding (3.58 ± 0.47 g dl(-1)) via the feeding tube (p<0.001). The duration of follow-up ranged from 1 to 49 months (mean 19 months).

CONCLUSION

The insertion of nose tube drainage and a nasojejunum feeding tube under fluoroscopic guidance is safe, and it provides effective relief from mediastinal abscesses in GEAL after oesophagectomy. Moreover, our findings indicate that two-tube insertion may be used as a selective procedure to treat mediastinal abscesses in post-operative GEAL. Advances in knowledge Directive drainage of mediastinal abscesses in post-operative GEAL may be an effective treatment.

Influences of oxygen pressure on optical properties and interband electronic transitions in multiferroic bismuth ferrite nanocrystalline films grown by pulsed laser deposition

Bismuth ferrite (BiFeO(3)) nanocrystalline films with the crystalline size of 27-40 nm have been grown on c-sapphire substrates under various oxygen pressures of 1 × 10(-4) to 1 Pa by pulsed laser deposition. The X-ray diffraction spectra show that the films are polycrystalline and present the pure rhombohedral phase. It was found that the Raman-active phonon mode E(TO1) shifts towards a higher energy side from 74 to 76 cm(-1) with increasing oxygen pressure, indicating a larger tensile stress in the films deposited at higher oxygen pressure. The X-ray photoelectron spectroscopy analysis suggests that the concentrations of both Fe(2+) ions and oxygen vacancies in the BiFeO(3) films increase with decreasing oxygen pressure. Moreover, the dielectric functions in the photon energy range of 0.47-6.5 eV have been extracted by fitting the transmittance spectra with the Tauc-Lorentz dispersion model. From the transmittance spectra, the fundamental absorption edge is observed to present a redshift trend with increasing the temperature from 8 to 300 K. Note that the optical band gap (E(g)) decreases with increasing the temperature due to the electron-phonon interactions associated with the interatomic distance in the BiFeO(3) films. However, the E(g) decreases from 2.88 to 2.78 eV with decreasing oxygen pressure at 8 K, which can be attributed to the increment of oxygen vacancies leading to the formation of some impurity states between the valence and conduction band. It can be concluded that the oxygen pressure during the film fabrication has the significant effects on microstructure, optical properties, and electronic band structure modification of the BiFeO(3) films.

Spectroscopic study on the enhanced excitation of an electron cyclotron resonance nitrogen plasma by pulsed laser ablation of an aluminum target

The influence of pulsed laser ablation of an aluminum target on the nitrogen plasma produced by electron cyclotron resonance (ECR) microwave discharge has been studied by optical emission spectroscopy (OES) with time and space resolution. The continuous wave (CW) feature of the optical emissions from the ECR nitrogen plasma turns to vary with time and space due to pulsed laser ablation and the expansion of the ablation-induced aluminum plume in the nitrogen plasma. The optical emissions from the nitrogen plasma increase significantly and the emission intensity of nitrogen molecular ions is observed to be more than 20 times higher with the target being ablated in comparison to the case without target ablation. The comparison of the optical emissions from the nitrogen plasma with those from the aluminum plume indicates that the excitation enhancement of the nitrogen plasma occurs in the region where the aluminum plume is expanding, revealing that the expansion of the aluminum plume leads to the excitation enhancement of the nitrogen plasma. Relevant mechanisms responsible for the excitation enhancement of the nitrogen plasma through hybrid processes of ECR microwave discharge and pulsed laser ablation are also discussed.

Practical and simple circuitry for the measurement of small capacitance

Practical and cost-effective circuitry with high sensitivity has been developed to measure a small capacitance using current compensation method. The circuitry uses an electronic switch to periodically connect or separate the capacitor under test (C(x)) from a reference capacitor (C(r)). When C(x) is connected in parallel with C(r) the total capacitance becomes C(x)+C(r). On the other hand, as C(x) is separated from C(r), the total capacitance is only C(r). This periodic change of the capacitance generates a periodic square-wave output with an amplitude in proportion to the capacitance of C(x). A high sensitivity of DeltaV/DeltaC=202.2 mV/pF has been achieved, making the circuitry a powerful tool in measuring small capacitances. Three applications have been performed to present its capability: (a) displacement, (b) height of liquid, and (c) angle of tilt. The experimental results demonstrate the performance of the circuitry.

Carbon dioxide laser microsurgery for tongue cancer: surgical techniques and long-term results

Thirty-seven consecutive patients with cancer of the anterior two-thirds of the tongue without clinical neck lymph nodes or distant metastasis were treated with transoral carbon dioxide (CO2) laser microsurgery. During the operation, a monopolar coagulation-suction device was applied to achieve a clear surgical field. Under a surgical microscope, we repeatedly palpated the soft tissue to identify the tumour margins, in particular the deep margin, to maintain adequate safe margins in three dimensions. We resected the tumour by en bloc procedures rather than by vaporization or debulking. Of the 28 patients in the T1 and T2 groups, 26 patients did not receive postoperative radiotherapy. The local control rate calculated by the methods of Kaplan and Meier in all 37 patients at 5 years was 93.6%. No local recurrence occurred in the T1 or T2 cases. Nine patients suffered from neck recurrence and the neck control rate at 5 years was 74.6%. Eight of these nine patients were salvaged by surgery with adjuvant radiotherapy, and six of them finally achieved disease-free status. The 5-year disease-free survival rate for our series was 88%. Our surgical techniques using CO2 laser microsurgery are effective and advantageous methods for excision of oral tongue cancer, especially stage I and II lesions.

Sequence analysis of the first complete cDNA clone encoding an American cockroach Per a 1 allergen

C3, designated as Per a 1.0103 according to WHO/IUIS nomenclature, encoding a novel American cockroach allergen of 395 aa (44.6 kDa), is the first complete cDNA clone with a translatable immunoreactive protein among the reported group 1 cockroach allergens. Its deduced amino acid sequence possesses a signal sequence, phosphorylation sites, mitochondrial energy transfer protein signatures, and four repeats each sharing striking similarity with the corresponding repeats of the other cockroach allergens. The latter similarity suggests that the group 1 cockroach allergens might have evolved from a primordial mitochondrial sequence by exon duplication.

Can endothelial seeding enhance patency and inhibit neointimal hyperplasia? Experimental studies and clinical trial of endothelial seeded venous prostheses

BACKGROUND

Venous prostheses have poor long-term patency; to improve this situation, experimental studies have been carried out.

METHODS

Methods of endothelial cell harvesting, prosthetic seeding and implantation mainly in the inferior vena cava were studied in 127 dogs. Evaluations were conducted by angiography, gross appearance, light, scanning and transmission electron microscopic observations, histo-fluorescent staining, as well as radioimmunoassay.

RESULTS

It was found that at five to ten days following implantation, the prosthetic endothelialisation could be reliably achieved in the seeded group and a 100% patency of the seeded inferior vena caval prostheses was attained at 100 days. The thickness of the neointima in the seeded group at 10 and 100 days was 299 microm and 302 microm, respectively. The metabolite of PGI2 from extrinsic arachidonic acid, 6-keto PGF1a, produced by cells from seeded graft was significantly higher than that from spontaneously formed cells and the reverse found with thromboxane B2. A temporary (one week) distal (femoral) arteriovenous fistula enhanced graft patency. These results indicated that the early endothelialisation of grafts by seeding enhanced the patency and inhibited intimal hyperplasia of venous prostheses. The clinical outcome was impressively improved from our previous experience with ten of eleven venous grafts patent over a follow-up period of six to nine years. These might result from the realization of early endothelialisation and its cells derived from seeding being able to produce significantly more PGI2 and less thromboxane B2.

CONCLUSIONS

The endothelial cell seeding technique may bring us much closer to an ideal venous prosthesis.

Reaction and binding of oligodeoxynucleotides containing analogues of O6-methylguanine with wild-type and mutant human O6-alkylguanine-DNA alkyltransferase

O6-Alkylguanine-DNA alkyltransferase (AGT) repairs DNA by transferring the methyl group from the 6-position of guanine to a cysteine residue on the protein. We previously found that the Escherichia coli Ada protein makes critical interactions with O6-methylguanine (O6mG) at the N1- and O6-positions. Human AGT has a different specificity than the bacterial protein. We reacted hAGT with double-stranded pentadecadeoxynucleotides containing analogues of O6mG. The second-order rate constants were in the following order (x10(-)5 M-1 s-1): O6mG (1.4), O6-methylhypoxanthine (1.6) > Se6-methyl-6-selenoguanine (0.1) > S6-methyl-6-thioguanine (S6mG) (0.02) >> S6-methyl-6-thiohypoxanthine (S6mH), O6-methyl-1-deazaguanine (O6m1DG), O6-methyl-3-deazaguanine (O6m3DG), and O6-methyl-7-deazaguanine (O6m7DG) (all <0.0001). Electrophoretic mobility shift assays were carried out to determine the binding affinity to hAGT. Oligodeoxynucleotides containing O6mG, S6mG and O6m3DG bound to AGT in the presence of competitor DNA with Kd values from 5 to 20 microM, while those containing G, S6mH, O6m1DG, and O6m7DG did not (Kd > 200 microM). These results indicate that the 1-, N2-, and 7- positions of O6mG are critical in binding to hAGT, while the 3- and O6-positions are involved in methyl transfer. These results suggest that the active site of ada AGT is more flexible than hAGT and may be the reason ada AGT reacts with O4mT faster than hAGT.

Inhibition of xanthine oxidase by benzothiazinone analogues

Fourteen synthetic benzothiazinone analogues were tested for their inhibitory effects on xanthine oxidase. The enzyme, xanthine oxidase (XO) catalyses the oxidation of hypoxanthine to xanthine and of xanthine to uric acid, which has a lambda max of 295 nm, forming the basis for a spectrophotometric assay for the activity of xanthine oxidase. The results showed that 2-amino-4H-1,3-benzothiazine-4-one (1), 2-guanidino-4H-1,3-benzothiazin-4-one (2) and rhodanine (3) display inhibitory effects on xanthine oxidase with an order of activity of IC50 = 5.54, 5.60 and 121.40 microM respectively. The apparent inhibition constants (Ki) were 5.12, 19.47 and 206.23 microM, and induced non-competitive, mixed type (non-competitive-uncompetitive) and mixed type (non-competitive-uncompetitive) inhibitions respectively with respect to the substrate xanthine.

Hierarchical cluster analysis applied to workers' exposures in fiberglass insulation manufacturing

The objectives of this study were to explore the application of cluster analysis to the characterization of multiple exposures in industrial hygiene practice and to compare exposure groupings based on the result from cluster analysis with that based on non-measurement-based approaches commonly used in epidemiology. Cluster analysis was performed for 37 workers simultaneously exposed to three agents (endotoxin, phenolic compounds and formaldehyde) in fiberglass insulation manufacturing. Different clustering algorithms, including complete-linkage (or farthest-neighbor), single-linkage (or nearest-neighbor), group-average and model-based clustering approaches, were used to construct the tree structures from which clusters can be formed. Differences were observed between the exposure clusters constructed by these different clustering algorithms. When contrasting the exposure classification based on tree structures with that based on non-measurement-based information, the results indicate that the exposure clusters identified from the tree structures had little in common with the classification results from either the traditional exposure zone or the work group classification approach. In terms of the defining homogeneous exposure groups or from the standpoint of health risk, some toxicological normalization in the components of the exposure vector appears to be required in order to form meaningful exposure groupings from cluster analysis. Finally, it remains important to see if the lack of correspondence between exposure groups based on epidemiological classification and measurement data is a peculiarity of the data or a more general problem in multivariate exposure analysis.

The inducible lactose operator-repressor system is functional in the whole animal

Mouse liver cell lines that bear a stably integrated lactose operon repressor (lacI) gene and a Ha-ras gene linked to a lactose operator-containing SV40 early promoter were generated. When grown in medium containing more than 0.1 mM isopropyl beta-D-thiogalactoside (IPTG), the Ha-ras gene was induced up to 20-fold. Maximum induction of Ha-ras gene expression occurred after 12 h of exposure. The tumorigenicity of these cell lines in syngeneic mice was enhanced when the mice were maintained on drinking water containing 12.5 mM IPTG. Ha-ras gene expression in tumors was strongly induced in the presence of IPTG in vivo. Induction of Ha-ras gene expression in mice was consistently observed after 48 hr of exposure to drinking water containing IPTG. This system provides an approach for studying the function of oncogene in vivo as well as other genes of interest.

Overexpression of MDM-2 mRNA and mutation of the p53 tumor suppressor gene in bladder carcinoma cell lines

To investigate the importance of oncogenes and tumor suppressor genes in bladder carcinogenesis, we determined the status of the expression of the MDM-2 and p53 genes and genetic alterations in the p53 gene in five bladder carcinoma cell lines and one kidney urothelial carcinoma cell line. Overexpression of MDM-2 mRNA was observed in three bladder carcinoma cell lines, J82, SCaBER, and BFTC-905. Amplification of the MDM-2 gene was not detected in any of the six cell lines by southern analysis. The deletion in the p53 gene was observed in J82, and point mutation was detected in J82 and BFTC-909, the kidney urothelial carcinoma cell line. In contrast, no mutations were found in codons 12, 13, and 61 in the Ha-ras and Ki-ras genes in these six cell lines. These results indicate that alterations in the p53-regulated pathway are important in bladder carcinogenesis.

[Treatment of Budd-Chiari syndrome with balloon dilatation and intraluminal stent]

We treated 33 cases of Budd-Chiari syndrome caused by localized occlusive lesions of the inferior vena cava (IVC) with balloon dilatation and stent deployment. Of the 33, 21 were male and 12 female. Complete "membranous" occlusion was found in 18, incomplete "membrane" in 6, and localized stenosis in 9. Seven cases recurred after transcardiac and membranotomy or cavoatial shunt or mesoatial shunt. Pure stent deployment was carried out in 24 cases, combined transcardiac and transfemoral approaches were used in 6, stent was placed during radical correction of IVC lesions in 3. Unrelieved intractable ascites were 5 cases because of hepatic venous occlusion or secondary cirrhosis, 3 of them were resolved by mesocaval anastomosis. The IVC pressures before and after stenting were 2.70 +/- 0.69kPa (1kPa = 0.98cmH2O) and 1.55 +/- 0.50kPa (P < 0.01) respectively. All but one (waiting for possible messocaval shunt) had excellent effect 6-23 months following the above mentioned therapy. We conclude that dilation and stenting plus necessary or additional surgery bring about a prosperous means for treating Budd-Chiari syndrome with localized lesions.

[Management of high risk Budd-Chiari syndrome with mesojugular shunt: report of 16 cases]

Standard procedures to treat Budd-Chiari syndrome caused by localized occlusions of the inferior vena cava and/or hepatic venous occlusion have been established. However, for those caused by long segmental occlusion or constriction accompanying with large amount of ascites, malnutrition, hypoalbumineamia, even pleural effusion, and breathlessness even orthopnea, no proper approaches are available. Hereby we report a new method of mesojugular shunt. Sixteen patients have been treated resulting in excellent result in 53% of patients and fair in 20%. The operative mortality was 13%. We consider mesojugular shunt is a proper means for relieving high risk patients with Budd-Chiari syndrome.

Epstein-Barr virus-associated lymphoproliferative disorders in oral cavity after heart transplantation: report of a case

Clinical manifestations of Epstein-Barr virus associated with post-heart transplant lymphoproliferative disorders (PTLD) are variable. Over one-half of the PTLD express extranodal presentations, of which gastrointestinal symptoms are the most common. Development of oral ulcers is an extremely rare initial manifestation with only three such cases having been reported. A case of oropharyngeal presentation of PTLD is described here. The clinical presentations and pathologic spectrums of PTLD are discussed. Posttransplant lymphoproliferative disorders are considered to be iatrogenic and life-threatening and are associated with immunosuppressive agents and Epstein-Barr virus infection. Early diagnosis and appropriate management could prevent the fatal progression of such disorders. The need to analyse tumor clonality along with observation of clinical presentations and microscopic pathology in order to diagnose PTLD is discussed.

The expression of proliferating cell nuclear antigen in hepatocellular carcinoma

BACKGROUND

Proliferating cell nuclear antigen (PCNA), also known as cyclin, is a cell cycle-related nuclear protein which accumulates in late G1 and S phases of proliferating cells. Previous researches have demonstrated it is a potentially useful tool for the study of tumor proliferative activity and have correlated it with tumor grade.

METHODS

In this study, PCNA was identified by utilizing streptavidin-biotin immunoperoxidase technique on formalin-fixed, paraffin-embedded tissue sections of 32 hepatocellular carcinomas that were obtained from resected surgical specimens.

RESULTS

The PCNA staining was entirely confined to the nucleus and showed gradation of intensity. The staining rates in tumor cells ranged from 0% to 99%. The mean (+/- S.D.) PCNA staining rates of 5 in grade I, 20 in grade II, and 7 in grade III hepatocellular carcinomas were 0.38 +/- 0.15%, 19.39 +/- 18.86% and 49.57 +/- 29.98%, respectively, and showed statistically significant difference (P < 0.01) between each other. There was no statistical difference in the mean PCNA staining rate of various histological types among hepatocellular carcinoma (P > 0.05). In 12 of 32 hepatocellular carcinomas, each PCNA staining of non-neoplastic hepatic tissue adjacent to the tumor was also evaluated and their mean PCNA rate (0.59 +/- 0.58%) revealed no significant difference (P > 0.05) from grade I hepatocellular carcinoma.

CONCLUSIONS

The hepatocellular carcinoma's mean proliferating cell nuclear antigen staining rates were correlated with its first three histological grades but revealed no statistical difference among its histological types. The mean proliferating cell nuclear antigen staining did not differentiate non-neoplastic hepatic diseases that were adjacent to hepatocellular carcinoma, including chronic active hepatitis, cirrhosis of liver, reactive hepatitis, schistosomiasis and nuclear dysplasia, from grade I hepatocellular carcinoma.

[Experimental study and clinical application of endothelium seeded vena caval prostheses]

One hundred and eleven mongrel dogs were used for this study. Endothelial cells were harvested from jugular vein or omentum with methods of collagenase digestion and density gradient separation. Animal model of prosthetic interposition into the inferior vena cava with or without distal arteriovenous fistula was established. The complete endothelialization was established 5 to 10 days following a high density seeding. The neointimal hyperplasia was inhibited. A 100-day 100% patency of prosthesis was reached. The seeded endothelium secreted higher level of PGI2 than normal control and lower level of TXB2, hence the positive effect of distal AVF functioning for a week on the patency was demonstrated. This method used in 10 cases with Budd-Chiari syndrome resulting in good outcome after 3 to 5 years follow-up. We conclude that the endothelial seeding technique has a promising future using in the venous circuit.

Simultaneous bilateral adrenal metastases from renal cell carcinoma. Surgical implications and review of the literature

We report a case of left-side renal cell carcinoma with contemporary bilateral adrenal involvement discovered preoperatively with computerized tomography and other imaging techniques. Surgical treatment consisted of radical nephrectomy with a nearly total contralateral adrenalectomy and the unroofing of a lower pole renal cyst. Postoperative cortisone acetate replacement was instituted. The surgical implications of renal cell carcinoma with metastasis are also discussed.

Relative cardiotoxicity and cytotoxicity of anthraquinonyl glucosaminosides

The cardiotoxicity and cytotoxicity for tumor cells of four new synthetic anthraquinonyl glucosaminosides were compared in vitro. The nonhydroxylated anthraquinone was not cardiotoxic, and its cytotoxic activity was the weakest of the compounds in the series. Increasing the number of hydroxyl groups on the anthraquinone moiety increased the inhibition of growth of L-1210 leukemia cells and pancreatic or colonic adenocarcinomas in a soft agar colony formation assay. However, cardiotoxicity was also increased in proportion to the number of hydroxyl groups present. The adenocarcinomas were slightly more sensitive than the leukemias to the inhibitory action of the dihydroxylated anthraquinonyl glucosaminosides on cell growth.

Synthesis of anthraquinonyl glucosaminosides and studies on the influence of aglycone hydroxyl substitution on superoxide generation, DNA binding, and antimicrobial properties

A series of anthraquinonyl glucosaminosides (10a-e) were synthesized by Koenigs-Knorr glycosidation of the corresponding aglycones (11a-e) with bromo sugar 12 followed by saponification. These glycosides were intended to serve as models to study the role played by the hydroxyl substituents on the aglycone portion of the antitumor anthracycline antibiotics. Superoxide generation as measured in rat heart sarcosomes was found to increase with the addition of successive hydroxyl groups to the anthraquinone nucleus. The 1,8-dihydroxy pattern was determined to generate significantly less superoxide than the 1,4-dihydroxy pattern. Hydroxyl substitution was also observed to stabilize the complex formed between the anthraquinones and DNA and was required for antibacterial activity against a number of Gram-positive organisms.

Lipid metabolism in cultured cells. XVIII. Comparative uptake of low density and high density lipoproteins by normal, hypercholesterolemic and tumor virus-transformed human fibroblasts

Serum lipoproteins control cell cholesterol content by regulating its uptake, biosynthesis, and excretion. Monolayers of cultured fibroblasts were used to study interactions with human high density (HDL) and low density (LDL) lipoproteins doubly labeled with [(3)H]cholesterol and (125)I in the apoprotein moiety. In the binding assay for LDL, the absence of specific LDL receptors in type II hypercholesterolemic fibroblasts was confirmed, whereas monolayers of virus-transformed human lung fibroblasts (VA-4) exhibited LDL binding characteristics essentially the same as normal lung fibroblasts. In the studies of HDL binding, specific HDL binding sites were demonstrated in normal and virus-transformed fibroblasts. In addition, type II hypercholesterolemic cells, despite the loss of LDL receptors, retained normal HDL binding sites. No significant competition was displayed between the two lipoprotein classes for their respective binding sites over a 5-fold concentration range. In VA-4 cells, the amount of lipoprotein required to saturate half the receptor sites was 3.5 micro g/ml (9 x 10(-9) M) for LDL and 9.1 micro g/ml (9 x 10(-8) M) for HDL. Pronase treatment reduced LDL binding by more than half but had no effect on HDL binding. Chloroquine, a lysomal enzyme inhibitor, stimulated net LDL uptake 3.5-fold by increasing internalized LDL but had essentially no effect on HDL uptake. Further experiments were conducted using doubly labeled lipoproteins to characterize the interaction of LDL and HDL with cells. While the cholesterol and protein moieties of LDL were incorporated into cells at similar rates, the uptake of the cholesterol moiety of HDL was 5 to 10 times more rapid than that of the protein component. Furthermore, the apoprotein component of LDL is extensively degraded following exposure, whereas the apoprotein moiety of HDL retains its macromolecular chromatographic characteristics. These results indicate that HDL and LDL bind to cultured cells at separate sites and that further processing of the two lipoprotein classes appears to take place by fundamentally different mechanisms.-Wu, J-D., J. Butler, and J. M. Bailey. Lipid metabolism in cultured cells XVIII. Comparative uptake of low density and high density lipoproteins by normal, hypercholesterolemic, and tumor virus-transformed human fibroblasts.

Lipid metabolism in cultured cells. XVI. Lipoprotein binding and HMG CoA reductase levels in normal and tumor virus-transformed human fibroblasts

The loss in feedback control of cholesterol biosynthesis in tumor cells was examined in tissue culture. Human fibroblasts from normal subjects, SV40 tumor virus-transformed cell lines, and homozygous familial hypercholesterolemic cells as reference, were grown in tissue culture. Experiments were conducted to relate the regulatory enzyme for cholesterol biosynthesis, HMG CoA reductase, and the membrane-located binding receptors for low density lipoproteins (LDL) that mediate feedback control in normal cells. Monolayers of virus-transformed tumor cells exhibited specific (125)I-labeled LDL binding of 152 +/- 21 ng/mg cell protein, which was essentially the same as that of normal fibroblasts (135 +/- 20 ng/mg). Binding of LDL by familial hypercholesterolemic cells used as controls was only 8 +/- 3 ng/mg under the same test conditions. Basal levels of HMG CoA reductase in tumor cells of 45.2 +/- 6.5 units/mg cell protein were about twice those of normal cells. However, in contrast to the lack of feedback control of this enzyme observed with tumors in vivo, in both the normal and the transformed cells in vitro, activity of the enzyme decreased about fourfold when serum lipids were added. These findings demonstrate that tumor cells growing in vitro contain a normal complement of the membrane-located binding receptors for low density lipoproteins and, although the basal levels are higher than normal, an effective feedback regulation of the enzyme HMG CoA reductase is retained.