[Diagnostic value of identifying location and amount of free gas in the abdominal cavity by multidetector computed tomography in patients with acute gastrointestinal perforation]

Objective: To evaluate the relationships between the location and extent of diffusion of free intraperitoneal air by multi-slice spiral CT (MSCT) and between the location and size of acute gastrointestinal perforation. Methods: This was a descriptive case series. We examined abdominal CT images of 33 patients who were treated for intraoperatively confirmed gastrointestinal perforation (excluding appendiceal perforation) in the Department of General Surgery, Nanfang Hospital between January and September 2022. We identified five locations of intraperitoneal air: the subphrenic space, hepatic portal space, mid-abdominal wall, mesenteric space, and pelvic cavity. We allocated the 33 patients to an upper gastrointestinal perforation (n=23) and lower gastrointestinal perforation group (n=10) base on intraoperative findings and analyzed the relationships between the locations of free gas and of gastrointestinal perforation. Additionally, we established two models for analyzing the extent of diffusion of free gas in the abdominal cavity and constructed receiver operating characteristic (ROC) curves to analyze the relationships between the two models and the size of the gastrointestinal perforation. Results: In the upper gastrointestinal perforation group, free gas was located around the hepatic portal area in 91.3% (21/23) of patients: this is a significantly greater proportion than that found in the lower gastrointestinal perforation group (5/10) (P=0.016). In contrast, free gas was located in the mesenteric interspace in 8/10 patients in the lower gastrointestinal perforation group; this is a significantly greater proportion than was found in the upper gastrointestinal perforation group (8.7%, 2/23) (P<0.010). The sensitivity of diagnosis of upper gastrointestinal perforation base on the presence of hepatic portal free gas was 84.8% and the specificity 71.4%. Further, the sensitivity of diagnosis of lower gastrointestinal perforation base on the presence of mesenteric interspace free gas was 80.0% and the specificity 91.3%. The rates of presence of free gas in the subdiaphragmatic area, mid-abdominal wall, and pelvic cavity did not differ significantly between the two groups (all P>0.05). Receiver operating characteristic curves showed that when free gas was present in four or more of the studied locations in the abdominal cavity, the optimal cutoff for perforation diameter was 2 cm, the corresponding sensitivity 66.7%, and the specificity 100%, suggesting that abdominal free gas diffuses extensively when the diameter of the perforation is >2 cm. Another model revealed that when free gas is present in three or more of the studied locations, the optimal cutoff for perforation diameter is 1 cm, corresponding to a sensitivity of 91.7% and specificity of 76.2%; suggesting that free gas is relatively confined in the abdominal cavity when the diameter of the perforation is <1 cm. Conclusion: Identifying which of five locations in the abdominal cavity contains free intraperitoneal air by examining MSCT images can be used to assist in the diagnosis of the location and size of acute gastrointestinal perforations.

[Analysis of transfusion effect of different platelet matching schemes in patients with platelet transfusion refractoriness]

Objective: To analyze the transfusion effect of different platelet matching schemes in patients with platelet transfusion refractoriness (PTR). Methods: A total of 94 patients with PTR received by Taiyuan Blood Center from January to December 2021 were retrospectively analyzed, including 26 males and 68 females, aged 53(34,66) years. Platelet antibody screening was performed by enzyme-linked immunosorbent assay (ELISA). For patients with positive human leukocyte antigen (HLA) class Ⅰ antibodies, Luminex platform liquid chip assay was used to identify the specificity of antibodies, and platelets with missing allelic expression antigen corresponding to their specific antibodies were found in the platelet donor gene database established in our laboratory. For patients with negative class HLA-Ⅰ antibody screening, medium and high-resolution HLA-A and B alleles were genotyped by polymerase chain reaction restriction sequence specific oligonucleotide (PCR-SSO), and the compatible platelets were searched from the platelet donor gene database by HLA cross-reactive group genotype matching scheme or directly selected by serological cross-matching. The PCI compliance rate and total transfusion effective rate of different mismatch site groups and different matching scheme groups were statistically analyzed. Results: Platelet antibody was detected in 39 of 94 PTR patients with a positive rate of 41.5%, and all of them were HLA-Ⅰ antibodies, and 1 case was accompanied by human platelet antigen (HPA) antibody. A total of 134 times of compatible platelets were supplied to 39 patients with HLA-Ⅰ antibody positive by using antibody avoidance matching method. And the total effective rate of transfusion was 97.8% (131/134); The PCI compliance rates of HLA-A antigen mismatch, HLA-B antigen mismatch and HLA-A and B antigen mismatch groups were 81.6% (31/38), 86.5% (32/37) and 78.6% (22/28), respectively. The total effective rate of transfusion was 97.4% (37/38), 94.6% (35/37) and 100% (28/28), respectively, with no statistical significance (all P>0.05). A total of 118 times of compatible platelets were provided by HLA antigen cross-reaction group genotype matching and serological cross-matching, 90 transfusion effects were collected during follow-up, and the total effective rate was 76.7% (69/90). Conclusion: The combination of different platelet matching schemes can improve the PCI compliance rate and the total effective rate of transfusion in PTR patients.

[Feasibility and safety of transseptal transcatheter mitral valve replacement for severe mitral regurgitation]

A prospective, single-center, single-arm, and open-design study was performed to evaluate the feasibility and safety of transseptal transcatheter mitral valve replacement in the treatment of severe mitral regurgitation. Patients with symptomatic moderate-severe or severe mitral regurgitation at high-surgical risk and anatomically appropriate for the HighLife transseptal mitral valve replacement (TSMVR) system in West China Hospital, Sichuan University from December 2021 to August 2022 were enrolled. Four patients (1 male and 3 females) with severe mitral regurgitation were included, with a median age of 68.5 (64.0-77.0) years and a median Society of Thoracic Surgeons (STS) score of 8.1% (6.4%-8.9%). Technical success was achieved in all the patients. There was no residual mitral regurgitation, paravalvular leakage, or left ventricular outflow tract obstruction. Three major cardiovascular and cerebrovascular adverse events occurred within 30 days after the procedure, including ventricular tachycardia, iatrogenic atrial septal defect closure, and heart failure readmission. The current study preliminarily demonstrates that transcatheter mitral valve replacement using the HighLife system via the transseptal approach for severe mitral regurgitation is feasible and relatively safe.

[Preliminary clinical experience of the novel transcatheter aortic valve system Prizvalve® for the treatment of severe aortic stenosis]

Objective: To evaluate the safety and efficacy of transcatheter aortic valve implantation (TAVI) with the novel Prizvalve^® system in treating severe aortic stenosis. Methods: This is a single-center, prospective, single-arm, observational study. A total of 11 patients with severe aortic stenosis with high risk or inappropriate for conventional surgical aortic valve replacement (SAVR) were included, and TAVI was achieved with the Prizvalve^® system between March 2021 and May 2021 in West China Hospital. Transthoracic echocardiography (TTE) was performed immediately after prosthesis implantation to evaluate mean transaortic gradient and maximal transaortic velocity. The device success rate was calculated, which was defined as (1) the device being delivered via the access, deployed, implanted and withdrawn, (2) mean transaortic gradient<20 mmHg (1 mmHg=0.133 kPa) or a maximal transaortic velocity<3 m/s post TAVI, and without severe aortic regurgitation or paravalvular leak post TAVI. TTE was performed at 30 days after the surgery, and all-cause mortality as well as the major cardiovascular adverse events (including acute myocardial infarction, disabling hemorrhagic or ischemic stroke) up to 30 days post TAVI were analyzed. Results: The age of 11 included patients were (78.1±6.3) years, with 8 males. A total of 10 patients were with NYHA functional class Ⅲ or Ⅳ. Devices were delivered via the access, deployed, implanted and withdrawn successfully in all patients. Post-implant mean transaortic gradient was (7.55±4.08) mmHg and maximal transaortic velocity was (1.78±0.44) m/s, and both decreased significantly as compared to baseline levels (both P<0.05). No severe aortic regurgitation or paravalvular leak was observed post TAVI. Device success was achieved in all the 11 patients. No patient died or experienced major cardiovascular adverse events up to 30 days post TAVI. Mean transaortic gradient was (9.45±5.07) mmHg and maximal transaortic velocity was (2.05±0.42) m/s at 30 days post TAVI, which were similar as the values measured immediately post TAVI (both P>0.05). Conclusions: TAVI with the Prizvalve^® system is a feasible and relatively safe procedure for patients with severe aortic stenosis and at high risk or inappropriate for SAVR. Further clinical studies could be launched to obtain more clinical experience with Prizvalve^® system.

Tuning the hysteresis of a metal-insulator transition via lattice compatibility

Structural phase transitions serve as the basis for many functional applications including shape memory alloys (SMAs), switches based on metal-insulator transitions (MITs), etc. In such materials, lattice incompatibility between transformed and parent phases often results in a thermal hysteresis, which is intimately tied to degradation of reversibility of the transformation. The non-linear theory of martensite suggests that the hysteresis of a martensitic phase transformation is solely determined by the lattice constants, and the conditions proposed for geometrical compatibility have been successfully applied to minimizing the hysteresis in SMAs. Here, we apply the non-linear theory to a correlated oxide system (V_1−xW_xO₂), and show that the hysteresis of the MIT in the system can be directly tuned by adjusting the lattice constants of the phases. The results underscore the profound influence structural compatibility has on intrinsic electronic properties, and indicate that the theory provides a universal guidance for optimizing phase transforming materials.

The effect of the lattice degrees of freedom on the metal-insulator transition of VO₂ remains a topic of debate. Here the authors show that the lattice compatibility of the high temperature tetragonal phase and the low-temperature monoclinic phase strongly influences the electronic transition, as manifested in the tunability of its hysteresis via chemical substitution.

[Comparision of risk factors and pathogens in patients with early- and late-onset ventilator-associated pneumonia in intensive care unit]

Objective: To compare risk factors and bacterial etiology in patients with early-onset versus late-onset ventilator-associated pneumonia (VAP) in intensive care unit (ICU). Methods: This prospective cohort study enrolled mechanically ventilated patients hospitalized for more than 48 hours in the first affiliated hospital, China Medical University from Jan 2012 to Jun 2016. Subjects were classified by ventilator status: early-onset VAP (< 5 d ventilation, E-VAP) or late-onset VAP (≥ 5 d ventilation, L-VAP). Potential risk factors and pathogen were evaluated. Results: A total of 4 179 patients in adult ICU were screened, 3 989 (95.5%) of whom were mechanically ventilated, 962 patients with mechanical ventilation time ≥ 48 h. VAP developed in 142 patients. E-VAP and L-VAP had different potential risk factors based on statistical analysis.Independent risk factors for E-VAP included male (OR=1.825, 95%CI 1.006-3.310), chronic obstructive pulmonary disease (COPD; OR=3.746, 95%CI 1.795-7.818), emergency intubation (OR=1.932, 95%CI 1.139-3.276), aspiration (OR=3.324, 95%CI 1.359-8.130). Whereas independent risk factors for L-VAP were coma (OR=2.335, 95%CI 1.300-4.194), renal dysfunction (OR=0.524, 95%CI 0.290-0.947), emergency intubation (OR=2.184, 95%CI 1.334-3.574). Mortality in E-VAP and L-VAP group were both higher than the non-VAP group[30.2%(19/63)vs 19.8%(162/820), P=0.044; 29.1%(23/79) vs 19.8%(162/820), P=0.046]. The pathogens isolated from early-onset versus late-onset VAP were not significantly different between groups, which the most common ones were acinetobacter baumannii, pseudomonas aeruginosa and klebsiella pneumoniae. Conclusion: E-VAP and L-VAP have different risk factors, however related pathogens are similar. Different specific preventive strategies are suggested based on different onset of VAP.

[A retrospective clinical study of sixty-three cases with persistent inflammation immunosuppression and catabolism syndrome]

Objective: To study the clinical characteristics and prognosis of patients with persistent inflammation immunosuppression and catabolism syndrome (PICS) in ICU. Methods: A total of 126 patients admitted to ICU (ICU stay of more than 10 days, age≥18 years) between January 2014 to December 2014 were retrospectively studied.Data were collected from electronic medical records including demographics, underlying disease, Acute Physiology and Chronic Health Evaluation Ⅱ (APACHEⅡ) score, Sequential Organ Failure Assessment (SOFA) score, laboratory parameters, ICU acquired infections and clinical outcome. Results: The overall incidence of PICS in ICU patients (ICU stay of more than 10 days) was 50.0%(63/126). There were no significant differences in baseline data such as gender, age, APACHEⅡscore, SOFA score and underlying diseases between the two groups(all P>0.05). Compared with the non-PICS group, there were more patients with gastrointestinal perforation in the PICS group (P=0.042), however, the medical or surgical admission did not differ between the two groups(P>0.05). During the stay in ICU, the PICS group showed a higher risk of developing acquired infections compared with the non-PICS group[PICS 63.5%(40/63) vs non-PICS 23.8%(15/63); P<0.001]. The infections were more caused by Candida in the PICS group than the non-PICS group [PICS 22.4%(11/49) vs non-PICS 2/17; P=0.003]. Moreover, the PICS group experienced longer stay in ICU[PICS(31.6±28.8) days vs non-PICS (20.4±11.3) days; P=0.0046] and higher ICU mortality [PICS 28.6%(18/63) vs non-PICS 6.3%(4/63), P=0.001]. Conclusion: PICS is a common manifestation of patients who stay in ICU more than 10 days, which is associated with high risk of ICU acquired infections, prolonged length of stay and high mortality.

Effects of tanshinone nanoemulsion and extract on inhibition of lung cancer cells A549

Danshen (Salvia miltiorrhiza), a Chinese medicinal herb, consists of several functional components including tanshinones responsible for prevention of several chronic diseases. This study intends to prepare tanshinone extract and nanoemulsion from danshen and determine their inhibition effect on lung cancer cells A549. A highly stable tanshinone nanoemulsion composed of Capryol 90, Tween 80, ethanol and deionized water with the mean particle size of 14.2 nm was successfully prepared. Tanshinone nanoemulsion was found to be more effective in inhibiting A549 proliferation than tanshinone extract. Both nanoemulsion and extract could penetrate into cytoplasm through endocytosis, with the former being more susceptible than the latter. A dose-dependent response in up-regulation of p-JNK, p53 and p21 and down-regulation of CDK2, cyclin D1 and cyclin E1 expressions was observed with the cell cycle arrested at G0/G1 phase. The cellular microcompartment change of A549 was also investigated. The study demonstrated that tanshinone nanoemulsion may be used as a botanic drug for treatment of lung cancer.

[Clinical observation on human alpha glucosidase in treatment of five patients with glycogen storage disease Ⅱ]

Objective: To evaluate the effect of enzyme replacement therapy (ERT) on glycogen storage disease typeⅡ(GSDⅡ). Method: The clinical data of three juvenile onset and two infant onset GSDⅡpatients were collected from First Affiliated Hospital of Sun Yat-sen University in October 2015 to July 2016.Patient 1 was female, the age of onset was 15 months. Patient 2 was male, the age of onset was 20 months. Patient 3 was female, the sister of patient 2, the age of onset was 47 months. Patient 4 was male, the age of onset was 5 months. Patient 5 was male, the age of onset was 1 month.The age at the start of ERT of the 5 patients was 32, 31, 56, 34, and 3 months respectively and the duration of ERT was 19, 9, 4, 5, 5 doses respectively.ERT was administered at 20 mg/kg every 2 weeks.Dexamethasone was regularly given before each infusion. Result: ERT was well tolerated, only one time, Patient 1 developed tachycardia and hypertension without using dexamethasone.Patient 2 underwent successfully ventilator weaning.Patient 1 underwent a tracheotomy, also needed mechanical ventilation treatment.Patient 4 noninvasive ventilation was tried. Conclusion: Recombinant human alpha-glucosidase treatment was effective and well tolerated in patients with GSDⅡ.

Identification and tissue-specific expression of a promethin-like homolog in amphioxus Branchiostoma belcheri

Promethins have been shown to be present in the vertebrates examined so far, yet little is known to date about them in invertebrates. Here we isolated a cDNA encoding a promethin-like homolog from the gut cDNA library of the amphioxus Branchiostoma belcheri, a cephalochordate occupying a nodal position transient from invertebrates to vertebrates. It contained a 504 bp open reading frame corresponding to a protein of 167 amino acids. Primary structural examination showed that the deduced promethin-like homolog was a transmembrane protein with three potential transmembrane helices, resembling the vertebrate promethins. Phylogenetic analysis showed that B. belcheri promethin-like homolog was located at the base of the vertebrate counterparts, suggesting that it represents the archetype of vertebrate promethins. Both Northern blotting and in situ hybridization histochemistry revealed a tissue-specific expression pattern of promethin-like gene, like that of mammalian promethins. This is the first report on invertebrate promethin-like homolog, paving the way for further insights into the evolution and function of promethins.

Combined cord blood stem cells and gene therapy enhances angiogenesis and improves cardiac performance in mouse after acute myocardial infarction

BACKGROUND

Gene and stem cell therapies hold promise for the treatment of ischaemic cardiovascular disease. However, combined stem cell and angiogenic growth factor gene therapy for acute ischaemic myocardium has not been previously reported. This study hypothesized that combined stem cell and gene therapy would not only augment new vessels formation but also improve myocardial function in acute ischaemic myocardium.

METHODS

Human angiopoietin-1 (Ang1) cDNA and VEGF(165) cDNA were ligated into AAV vector. The purified CD34(+) cells were obtained from human umbilical cord blood samples. Cord blood CD34(+) cells were transduced with AAV vector encoding either the human Ang1 (AAV-Ang1) or VEGF(165) (AAV-VEGF) cDNA alone, or both (AAV-Ang1 plus VEGF). Immediately after ligation of the left anterior descending coronary artery in male SCID mice, culture-expanded CD34(+) cells transduced with AAV-Ang1, AAV-VEGF or AAV-Ang1 plus VEGF were injected intramyocardially at the left anterior free wall.

RESULTS

Western blot showed that Ang1 and VEGF protein expressions were enhanced in the CD34(+)cells transduced with AAV-Ang1 and AAV-VEGF, respectively. Infarct size significantly decreased and capillary density significantly increased after treatment with CD34(+)/AAV-Ang1 plus VEGF when compared with treatment by CD34(+) only. Combined therapy with CD34(+) and AAV-Ang1, CD34(+) and AAV-VEGF, CD34(+) and AAV-Ang1 plus VEGF, all showed significantly higher cardiac performance in echocardiography than the therapy with CD34(+) alone 4 weeks after myocardial infarction.

CONCLUSIONS

Combined therapy with human umbilical cord blood CD34(+) cells and both Ang1 and VEGF genes reduced infarct size, attenuated the progression of cardiac dysfunction and increased capillary density in acute myocardial infarction in mice.

The multidrug resistance of tumour cells was reversed by tetrandrine in vitro and in xenografts derived from human breast adenocarcinoma MCF-7/adr cells

Multidrug resistance (MDR) is one of the main obstacles limiting the efficacy of chemotherapy treatment of tumours. One of the main causes of MDR is linked to the overexpression of P-glycoprotein (P-gp). This study aimed to characterise tetrandrine (Tet), a potent inhibitor of P-gp mediated MDR. Cytotoxicity was determined by the tetrazolium (MTT) assay. A MCF-7/adr cell xenograft model was established to investigate the effect of Tet on reversing MDR in vivo. Mechanistic experiments were conducted to examine the uptake, efflux and accumulation of doxorubicin (Dox) and Fura-2, and to assess lipid membrane fluidity. Tet potentiated the cytotoxicity of Dox; a 20.4-fold reversal of resistance was achieved in the presence of 2.5 micromol/l of Tet. Accumulation and efflux studies with the P-gp substrates, Dox and Fura-2, demonstrated that Tet inhibited the P-gp-mediated drug efflux. In addition, Tet lowered cell membrane fluidity in a concentration-dependent manner. In mice bearing the MDR MCF-7/adr cell xenografts, coadministration of Tet potentiated the antitumour activity of doxorubicin without a significant increase in toxicity. Tet was an extremely potent MDR modulator both in vitro and in vivo, without apparently enhancing the toxicity of the co-administered drugs. Hence, Tet holds great promise as a MDR modulator for the treatment of P-gp-mediated MDR cancers.

Oral self-administration of ethanol, phencyclidine, methadone, pentobarbital and quinine in rhesus monkeys

RATIONALE

Simultaneous and sequential drug use among clinical populations is the norm, whereas the pattern of self-administration of multiple drugs among non-human primate populations has not been thoroughly explored.

OBJECTIVES

To determine the relationship between the preferences and intakes of a large group of rhesus monkeys exposed to various orally available solutions.

METHODS

Thirteen male and eleven female young adult rhesus monkeys (Macaca mulatta) were exposed to orally available drug solutions using a concurrent choice (drug and water) procedure, where fluid delivery was made contingent upon single spout contacts (fixed ratio one).

RESULTS

Ethanol (0.25-16% w:v) produced biphasic effects on the number of fluid deliveries obtained, with peak ethanol preferences over water demonstrated at the 1-2% w:v concentrations. No preferences for the N-methyl-d-aspartate receptor antagonist phencyclidine or water were demonstrated at lower concentrations (0. 0078125-0.125 mg/ml) and, at higher concentrations (0.25, 0.5 mg/ml), a preference for water was demonstrated. The mu opioid receptor agonist methadone (0.001-0.3 mg/ml) and the prototypic bitter substance quinine (0.001-0.3 mg/ml) failed to produce preferences for drug or water. A large preference for water over the barbiturate pentobarbital (0.01-3 mg/ml) was also demonstrated. After rank-ordering the subjects based on their drug preferences or intakes, modest to no correlations across drugs were demonstrated.

CONCLUSIONS

These results reveal that a robust ethanol preference is not predictive of a preference for drugs of abuse from other classes and suggests that fluid intakes were correlated, irrespective of the presence or absence of drug in the solution.

Circumvention of tumor multidrug resistance by a new annonaceous acetogenin: atemoyacin-B

AIM

To explore the effect of atemoyacin-B (Ate) on overcoming multidrug resistance (MDR).

METHODS

Bullatacin (Bul) was used as a positive control. Cytotoxic effects of Bul and Ate were studied with cell culture of human MDR breast adenocarcinoma cells, MCF-7/Dox and human KBv200 cells, and their parental sensitive cell lines MCF-7 and KB. Cytotoxicity was determined by tetrazolium (MTT) assay. The function of P-glycoprotein (P-gp) was examined by Fura 2-AM assay. Cellular accumulation of doxorubicin (Dox) was determined by fluorescence spectrophotometry. Apoptosis was measured by flow cytometry.

RESULTS

IC50 of Ate for MCF-7/Dox, MCF-7, KBv200, and KB cells were 122, 120, 1.34, and 1.27 nmol.L-1, respectively. IC50 of Bul for MCF-7/Dox, MCF-7, KBv200, and KB cells were 0.60, 0.59, 0.04, and 0.04 nmol.L-1, respectively. The cytotoxicities of Bul and Ate to MDR cells were similar to those to parental sensitive cells. Bul and Ate markedly increased cellular Fura-2 and Dox accumulation in MCF-7/Dox cells, but not in MCF-7 cells. The rates of apoptosis in MDR cells were similar to those in sensitive cells induced by Ate.

CONCLUSION

There was no cross-resistance of P-gp positive MCF-7/Dox and KBv200 cell lines to Bul and Ate as compared with their sensitive P-gp negative MCF-7 and KB cell lines. The mechanism of the circumvention of MDR was associated with the decrease of P-gp function and the increase of cellular drug accumulation in MDR cells.

Clinical and biological characteristics of acute promyelocytic leukemia in Taiwan: a high relapse rate in patients with high initial and peak white blood cell counts during all-trans retinoic acid treatment

Acute promyelocytic leukemia (APL) patients treated with all-trans retinoic acid (ATRA) and chemotherapy have been shown to have better outcome than those treated with conventional chemotherapy alone. However, the biological characteristics of leukemic cells and their clinical implications in patients treated with ATRA have not been well established. In this study, the biological and clinical features of 30 APL patients were reported. The risk factors for relapse and for occurrence of retinoic acid (RA) syndrome, which might cause morbidity or mortality of patients after ATRA treatment, were also analyzed. All patients showed 15;17 translocation by cytogenetic and/or gene analysis. Patients in this study had higher white blood cell (WBC) counts and a higher incidence of additional abnormalities than those from other areas. The ratio of long (L) form to short (S) form PML-RAR alpha fusion transcript was 1.8:1, a value lower than that of Latino patients but higher than that of Italians. Leukemic cells from four patients showed coexpression of T cell-associated antigen CD2 which was highly correlated with S form fusion transcript. Nine (36%) of the 25 patients treated with ATRA developed RA syndrome; all but one were successfully controlled by corticosteroid. Complete remission (CR) rate was 84%. Patients with high WBC counts tended to develop RA syndrome and had increased risk of relapse. Isochromosome for the long arm of the derivative chromosome 17, ider(17q), as an additional chromosomal abnormality was also associated with poor outcome in this study. In conclusion, APL in this study showed some different biological characteristics compared with those reported in other areas. High WBC count was a risk factor for relapse and development of RA syndrome after ATRA treatment. The prognostic implication of the presence of ider(17q) needs further clarification.

Clinical, haematological and molecular studies in patients with chromosome translocation t(7;11): a study of four Chinese patients in Taiwan

Translocation t(7;11)(p 15;p15) is an uncommon but recurrent chromosome aberration in acute myeloid leukaemia (AML). which occurs mostly in oriental patients and in AML M2 or, occasionally, M4 subtype. Recently, a consistent chimaeric fusion transcript NUP98-HOXA9 was found in several cases of t(7;11). Four AML cases with the chromosome abnormality in Taiwan are described. They were all adults with ages ranging from 30 to 41 years (median 36 years). Three of them were diagnosed as having AML M2; the remaining one as M4. Marked dyserythropoiesis was demonstrated in two patients. All four patients showed pan-myeloid antigen CD13 on the leukaemic cells, but none coexpressed lymphocyte-associated antigens and neither of the two patients studied for CD34 expression had positive staining. NUP98-HOXA9 fusion transcript was detected in both patients who had molecular analysis and the breakpoints on chromosome 11 and 7 respectively were similar to those previously reported. They all received conventional induction chemotherapy, but only one achieved a complete remission (CR) with short duration. This study and others reported in the literature suggest a racial or geographical predisposition among oriental patients to AML with t(7;11) and that this is associated with a poor prognosis. The molecular detection of NUP98-HOXA9 fusion transcript would be a useful method for the diagnosis of t(7;11) and also for monitoring disease status after treatment.

New dual electrochemical detector for microbore liquid chromatography. Determination of dopamine and serotonin in rat striatum dialysates

A new type of liquid chromatographic (LC) dual thin-layer amperometric detector for the simultaneous measurement of trace levels of dopamine and serotonin in microdialysates is described. The concentrations of these analytes in rat dialysates are usually in the sub-nanomolar concentration range (typically, 0.10-5.00 pg in 5-microl dialysates). With this dual electrode, a glass-lined microbore column provides excellent sensitivity, selectivity, and separation. In addition, a three- to five-fold improvement in anodic current or cathodic responses over conventional dual electrodes in microbore LC can be achieved. Due to the irreversible electrochemical properties of some interference peaks, this dual electrode provides reliable measurement of dopamine based on the cathodic signal. The detection limit (signal-to-noise ratio = 3) of this assay is 0.02 pg per injection for dopamine or serotonin. This new dual electrode allows the simultaneous measurements of basal dopamine and serotonin in rat striatum dialysates without the use of re-uptake inhibitors in perfusion medium.

Transcription termination at the Escherichia coli thra terminator by spinach chloroplast RNA polymerase in vitro is influenced by downstream DNA sequences

We have investigated the mechanism of transcription termination in vitro by spinach chloroplast RNA polymerase using templates encoding variants of the transcription-termination structure (attenuator) of the regulatory region of the threonine (thr) operon of Escherichia coli. Fourteen sequence variants located within its d(G+C) stem-loop and d(A+T)-rich regions were studied. We found that the helix integrity in the stem-loop structure is necessary for termination but that its stability is not directly correlated with termination efficiency. The sequence of the G+C stem-loop itself also influences termination. Moreover, the dA template stretch at the 3' end of the terminator plays a major role in termination efficiency, but base pairing between the A and U tract of the transcript does not. From the studies using deletion variants and a series of mutants that alter the sequences immediately downstream from the transcription termination site, we found that termination of transcription by spinach chloroplast RNA polymerase was also modulated by downstream DNA sequences in a sequence-specific manner. The second base immediately following the poly(T) tract is crucial for determining the termination efficiency by chloroplast RNA polymerase, but not of the T7 or E.coli enzymes.

Ligation of multiple DNA fragments through uracil-DNA glycosylase generated ligation sites

Images

[Immunohistochemical study on diamine oxidase in mammary cancer and adenosis]

In recent years, an obvious increase of diamine oxidase (DAO) in both blood and tumor tissues has been reported In this assay we observed an increased content and distribution of DAO in mammary cancer and adenosis by immunohistochemistry. The results show that: 1. DAO staining was strongly positive in mammary cancer and the brownish granules were spread over the cytoplasm; 2. In the adenosis of mammary gland, DAO was positive or weakly positive, but those hyperplastic ducts in it appeared to be strongly positive and the brownish granules distributed spotted; 3. The normal mammary tissue presented weak positive or negative DAO reaction. These observations indicated that the malignant tumor and hyperplastic changes of mammary gland induce increase of DAO in the cells, and the higher the DAO content, the greater the possibility of malignant changes.

[Immunohistochemical observation of angiotensin converting enzyme in acute lung injury]

The morphological changes of acute lung injury of rabbits, particularly the ACE content in the vascular endothelium of lung were studied with immunohistochemical methods and Q-970 image analysor. The activity of ACE in serum collected from the arteries was also estimated. The results showed that during the process of acute lung injury, the lung vascular endothelium was severely damaged with an obvious decrease of ACE content and activity. It indicates that decrease of ACE content and activity may play an important role in the pathogenesis of acute lung injury and may also be the sensitive criteria in expressing damage of the vascular endothelium in the lungs.

[Application of microwaves in special and immunohistochemical staining]

Special and immunohistochemical staining are commonly used in clinicopathological diagnosis. However, the processing of most staining methods takes quite a long time even to 1-2 days. Application of microwaves to the staining process such as for nerve myelin, striated muscle fibers, acid mucin, melanin, hemosederin, aspergillus, basement membrane, HHF-35, desmin, cytokeratin, etc. The results were satisfactory similar to those by the ordinary methods and the time required was greatly shortened. Besides, the titres of antibody required were also similar as those used for routine immunohistochemical technique. It is assumed that application of microwaves in staining process might be valuable for pathological diagnosis and particularly the efficiency could be greatly enhanced.

[Immunochemical study of Cu-Zn-superoxide dismutase (Cu-Zn-SOD) in multiple organ failure of rats]

70 Wistar rats were divided into normal group and experimental group (intra-peritoneal injection of zymosan (75mg per 100g wt). All rats were sacrificed at 1, 2 and 4-5 days. The histological changes in the lung, liver, kidney and brain agreed with the alterations recognized in multiple organ failure. On immuno-histochemical examination, we found that the content of Cu-Zn-SOD in bronchiolar columnar cells, liver cells, renal tubular epithelial cells and neuron cells of brain was decreased as compared with normal control group (P less than 0.05 or P less than 0.01). These phenomena indicated that the utilization of Cu-Zn-SOD was increased due to excessive production of oxygen free radicals in multiple organ failure.

[Pathological changes in an animal model of acute pulmonary injury induced by hemorrhagic shock and E. coli infection]

An animal model of API similar to RDS was established by feeding the rabbits with live E. Coli (10(11)/kg B.W.) and bleeding them till a mean arterial pressure of 6.0 kPa was maintained for 90 minutes. After resuscitation, there were decrease of PaO2, increase of respiratory rate as well as lung edema. Histological and electron microscopic examination showed interstitial and alveolar edema. The tight junctions both in alveolar epithelium and capillary endothelium showed alterations including discontinuity, irregularity, and free-ended strands being present as early as the 4th hour by freeze-fracture technique. Impairment of the tight junctions is considered to be the main route of fluid leakage from pulmonary capillaries inducing pulmonary edema.

[Trial production of tabellae papaini compositus]

This article reports on the technological standards for trial production of Tabellae Papaini Compositus, including the prescription, preparation, quality control, indications and usage. The clinical observation results show that the total effect rate comes to 94.06 percent for some inflammatory diseases.