Atomically accurate site-specific ligand tailoring of highly acid- and alkali-resistant Ti(iv)-based metallamacrocycle for enhanced CO2 photoreduction

Skillfully engineering surface ligands at specific sites within robust clusters presents both a formidable challenge and a captivating opportunity. Herein we unveil an unprecedented titanium-oxo cluster: a calix[8]arene-stabilized metallamacrocycle (Ti16L4), uniquely crafted through the fusion of four "core-shell" {Ti4@(TBC[8])(L)} subunits with four oxalate moieties. Notably, this cluster showcases an exceptional level of chemical stability, retaining its crystalline integrity even when immersed in highly concentrated acid (1 M HNO3) and alkali (20 M NaOH). The macrocycle's surface unveils four specific, customizable μ2-bridging sites, primed to accommodate diverse carboxylate ligands. This adaptability is highlighted through deliberate modifications achieved by alternating crystal soaking in alkali and carboxylic acid solutions. Furthermore, Ti16L4 macrocycles autonomously self-assemble into one-dimensional nanotubes, which subsequently organize into three distinct solid phases, contingent upon the specific nature of the four μ2-bridging ligands. Notably, the Ti16L4 exhibit a remarkable capacity for photocatalytic activity in selectively reducing CO2 to CO. Exploiting the macrocycle's modifiable shell yields a significant boost in performance, achieving an exceptional maximum CO release rate of 4.047 ± 0.243 mmol g-1 h-1. This study serves as a striking testament to the latent potential of precision-guided surface ligand manipulation within robust clusters, while also underpinning a platform for producing microporous materials endowed with a myriad of surface functionalities.

[Source Apportionment and Potential Ecological Risk Assessment of Soil Heavy Metals in Typical Industrial and Mining Towns in North China]

To understand the status of heavy metals in soils of typical industrial and mining towns and quantitatively analyze the potential sources, the contents of seven heavy metals (Cd, As, Pb, Cr, Cu, Ni, and Zn) in 150 surface soils in Xuanhua District, Zhangjiakou City, Hebei Province were collected and examined. The geoaccumulation index and potential ecological risk index methods were used to evaluate the heavy metal pollution status and potential ecological risk. Principal component analysis (PCA) and the positive matrix factorization (PMF) model were used to comprehensively analyze the pollution sources of seven heavy metals, and geostatistics was used to identify the high contribution areas of potential sources. The results revealed that:① the average values of heavy metals in the study area ranged from 0.23-103.34 mg·kg-1, among which the average contents of Cd, Pb, Cu, and Zn were higher than the soil background value of Hebei Province. ② The results of the geoaccumulation and potential ecological risk indices demonstrated that the degree of pollution of the seven heavy metals was in the following order:Cd>Pb>Cu>Zn>Ni>As>Cr, the content of Cd in 16% sites was above a moderate pollution level, and the potential ecological risk of heavy metals in more than 95% sites was at a light risk level. ③ The main sources of accumulation of the seven heavy metals in the study area were combined sources of industry and traffic, natural sources, and agricultural sources, with their contribution rates of 33.1%, 48.7%, and 18.2%, respectively. Among them, Cd, Pb, Cu, and Zn were primarily affected by the combined sources of industry and transportation; Cr, Ni, and As were mainly affected by natural sources, whereas Cd and some As were affected by agricultural sources. The organic combination of PCA, PMF model, and geostatistical methods confirmed the results of each analysis, which increased the reliability of the analytical results of heavy metal sources.

Stepwise assembly of thiacalix[4]arene-protected Ag/Ti bimetallic nanoclusters: accurate identification of catalytic Ag sites in CO2 electroreduction

The accurate identification of catalytic sites in heterogeneous catalysts poses a significant challenge due to the intricate nature of controlling interfacial chemistry at the molecular level. In this study, we introduce a novel strategy to address this issue by utilizing a thiacalix[4]arene (TC4A)-protected Ti-oxo core as a template for loading Ag1+ ions, leading to the successful synthesis of a unique Ag/Ti bimetallic nanocluster denoted as Ti8Ag8. This nanocluster exhibits multiple surface-exposed Ag sites and possesses a distinctive "core-shell" structure, consisting of a {Ti4@Ag8(TC4A)4} core housing a {Ti2O2@Ag4(TC4A)2} motif and two {Ti@Ag2(TC4A)} motifs. To enable a comprehensive analysis, we also prepared a Ti2Ag4 cluster with the same {Ti2O2@Ag4(TC4A)2} structure found within Ti8Ag8. The structural disparities between Ti8Ag8 and Ti2Ag4 provide an excellent platform for a comparison of catalytic activity at different Ag sites. Remarkably, Ti8Ag8 exhibits exceptional performance in the electroreduction of CO2 (eCO2RR), showcasing a CO faradaic efficiency (FECO) of 92.33% at -0.9 V vs. RHE, surpassing the FECO of Ti2Ag4 (69.87% at -0.9 V vs. RHE) by a significant margin. Through density functional theory (DFT) calculations, we unveil the catalytic mechanism and further discover that Ag active sites located at {Ti@Ag2(TC4A)} possess a higher εd value compared to those at {Ti2O2@Ag4(TC4A)2}, enhancing the stabilization of the *COOH intermediate during the eCO2RR. This study provides valuable insights into the accurate identification of catalytic sites in bimetallic nanoclusters and opens up promising avenues for efficient CO2 reduction catalyst design.

Al12Co4: a pioneering heterometallic aluminum oxo cluster with surface-exposed Co sites for the oxygen evolution reaction

We report an unprecedented heterometallic aluminum oxo cluster (AlOC) containing four surface-exposed CoII sites, designated as Al12Co4, protected by four t-butylcalix[4]arene (TBC[4]) molecules. The Al12Co4 nanocluster represents a significant advancement on multiple innovative fronts. First, it stands as an pioneering example of an AlIII-based metallocalixarene nanocluster. It is also the first instance of heterometallic AlOCs shielded by macrocyclic ligands. Notably, this cluster also holds the distinction of being the highest nuclearity Al-Co bimetallic nanocluster known to date. Additionally, by depositing Al12Co4 on carbon nanotubes (CNTs) as a supported catalyst, we investigated its electrocatalytic performance for the oxygen evolution reaction in alkaline media. To reach a 10 mA cm-2 current density in alkaline solution, the Al12Co4@CNT electrode needs overpotential as low as 320 mV.

Unveiling the Remarkable Stability and Catalytic Activity of a 6-Electron Superatomic Ag30 Nanocluster for CO2 Electroreduction

Nanocluster catalysts face a significant challenge in striking the right balance between stability and catalytic activity. Here, we present a thiacalix[4]arene-protected 6-electron [Ag30(TC4A)4(iPrS)8] nanocluster that demonstrates both high stability and catalytic activity. The Ag30 nanocluster features a metallic core, Ag104+, consisting of two Ag3 triangles and one Ag4 square, shielded by four {Ag5@(TC4A)4} staple motifs. Based on DFT calculations, the Ag104+ metallic kernel can be viewed as a trimer comprising 2-electron superatomic units, exhibiting a valence electron structure similar to that of the Be3 molecule. Notably, this is the first crystallographic evidence of the trimerization of 2-electron superatomic units. Ag30 can reduce CO2 into CO with a Faraday efficiency of 93.4% at -0.9 V versus RHE along with excellent long-term stability. Its catalytic activity is far superior to that of the chain-like AgI polymer ∞1{[H2Ag5(TC4A)(iPrS)3]} (∞1Agn), with the composition similar to Ag30. DFT calculations elucidated the catalytic mechanism to clarify the contrasting catalytic performances of the Ag30 and ∞1Agn polymers and disclosed that the intrinsically higher activity of Ag30 may be due to the greater stability of the dual adsorption mode of the *COOH intermediate on the metallic core.

[Screening and validation of pivotal genes in hepatitis B virus-associated hepatocellular carcinoma]

Objective: To screen the pivotal genes involved in the occurrence and development of HBV-associated HCC. Additionally, perform validation and biological function analysis to evaluate changes in the expression of pivotal genes and their prognostic value in patients with hepatocellular carcinoma. Methods: The GSE121248 gene expression profile data of HBV-HCC patients were searched and downloaded from the GEO database. The R language was used to compare the differences in gene expression between hepatocellular carcinoma and paracancerous tissues. KEGG and GO function enrichment analyses were performed on the differential genes. PPI plots and pivotal gene screening were carried out through online tools like STRING and Cytoscape software. 369 cases of hepatocellular carcinoma and 160 healthy controls in TCGA and GTEx were used as validation cohorts to verify the expression levels of the pivotal genes. A Kaplan-Meier plot was drawn to evaluate the prognostic value of the pivotal gene. Results: A total of 120 differentially expressed genes were screened, of which 89 were up-regulated and 31 were down-regulated. Differential genes were mainly enriched in the metabolic pathways related to retinol metabolism, cytochrome P450 metabolism, and the p53 signaling pathway. The top 10 differential genes were selected as pivotal genes by the Cytoscape plug-in cytoHubba. There were significant differences in the expression levels of four types of CCNB1, CDK1, RRM2, and TOP2A genes in the validation cohort. All four types of genes were up-regulated. Survival analysis showed that patients with elevated expression levels of four genes had a poorer prognosis, with statistical differences in results. Conclusion: Four types of genes, CCNB1, CDK1, RRM2, and TOP2A, have high expression levels in patients with HBV-HCC and are correlated to shorter survival times, making them a potential target for diagnosis, prognosis, and treatment.

[Clinical characteristics and prognostic factors of patients with anti-melanoma differentiation-associated gene 5 antibody-positive dermatomyositis associated interstitial lung disease]

Objective: To analyze the clinical characteristics and prognostic factors of patients with anti-melanoma differentiation-associated gene 5 (anti-MDA5)-positive dermatomyositis associated interstitial lung disease (DM-ILD). Methods: The patients with MDA5+DM-ILD who were admitted to Department of Respiratory Medicine, Nanjing Drum Tower Hospital from January 2017 to March 2021 were enrolled. The clinical data and survival information were analyzed retrospectively. Patients were divided into survival group or death group, and rapid progressive ILD (RP-ILD) group or non-rapid progressive ILD group, according to their survival status and clinical progression. Results: A total of 105 patients with anti-MDA5+DM-ILD (median age of onset 54 years) were enrolled, 58% being female (61 cases). The main sub-type of dermatomyositis was amyopathic dermatomyositis (n=74, 70%), followed by dermatomyositis (n=31, 30%). The main extrapulmonary manifestations were skin lesions (n=60, 57.1%), muscle manifestations(n=20, 19%) and arthralgia/arthritis (n=20, 19%). 15.4% of the patients had positive ANA (antibody titer≥1∶320), and 61.9% of the patients had anti-RO-52 kDa antibody. A total of 66 patients (62.8%) developed RP-ILD, and 58 patients (56.3%) died. Lower oxygenation index (OR=0.974, 95%CI:0.954-0.994, P=0.012) and no joint pain (OR=0.032, 95%CI: 0.002-0.663 P=0.026) were independent risk factors for RP-ILD. Cox regression analysis showed that RP-ILD (HR=3.194, 95%CI:1.025-9.954, P=0.045), older than 53 years (HR=3.450, 95%CI: 1.388-8.577, P=0.008), ferritin level more than 1 330.5 ng/ml (HR=3.032, 95%CI 1.208-7.610, P=0.018) and C-reactive protein (CRP) above 16.95 mg/L (HR=2.794, 95%CI:1.102-7.084, P=0.030) were independent predictors of mortality. Conclusions: The clinical manifestations of patients with anti-MDA5+DM-ILD presenting to the respiratory department were heterogeneous, with most being amyopathic dermatomyositis, and both the incidence of RP-ILD and the risk of death were high. Even in the absence of associated rash, joint, or muscle manifestations, anti-MDA5 antibody screening should be considered in patients with rapidly progressive ILD who were negative on baseline autoantibody screening but positive for anti-RO52kDa antibody.

Auxiliary Carboxylate-Induced Assembly of Calix[6]arene-Polyoxotitanate Hybrid Systems with Photocatalytic Activity in the Oxidation of Sulfides

This study used the tert-butylcalix[6]arene (TBC[6]) as the ligand and successfully synthesized six TBC[6]-stabilized titanium-oxo clusters (TOCs) by the one-step solvothermal reaction. These six compounds were [Ti₄O₂(TBC[6])₂] (Ti₄), {Ti₂(TBC[6])(EtO)₂(SaH₂)₂} (Ti₂-SA, H₂Sa = squaric acid), {Ti₂(TBC[6])₂(EtO)₂(Oa)} (Ti₂-OA, H₂Oa = oxalic acid), [H₂Ti₄(TBC[6])(BA)₂(EtO)₁₀] (Ti₄-BA, HBA = benzoic acid), [Ti₆O₂(TBC[6])(BA)₄(OⁱPr)₁₀] (Ti₆-BA), and [Ti₈(TBC[6])₂(Sal)₄(EtO)₁₆] (Ti₈-Sal, H₂Sal = salicylic acid). These clusters contain one or two TBC[6] ligands, with the biconical or monoconical configuration, greatly increasing the variety of TOCs it could support. The introduction of auxiliary carboxylic ligands can further stimulate the growth of structures, with the cluster core gradually increased from {Ti-TBC[6]-Ti} to {Ti₂-TBC[6]-Ti₂}, to {Ti₃-TBC[6]-Ti₃}, and finally to {Ti₃-TBC[6]-Ti₂-TBC[6]-Ti₃} with 3.1 nm length. Structural regulation may affect their solution stability, absorption spectra, and photocurrent response. The study of catalytic activities shows that these clusters can be used as recyclable heterogeneous photocatalysts for the oxidation of sulfide to sulfoxide. The catalytic efficiency of the TBC[6]-Ti_x system is closely related to the cluster structure, and the exposure of the Ti site on the catalyst surface can significantly enhance the catalytic activity of the clusters.

Polymolybdate-guided assembly of a thiacalix[4]arene-protected Ag nanocluster for electrocatalytic CO2 reduction

A large polymolybdate-templated {Ag49Mo16} cluster protected by six thiacalix[4]arene (TC4A) molecules was synthesized by a one-pot solvothermal reaction. Structural analysis shows that the {Ag49Mo16} is assembled by inserting a [Mo₆O₂₂]^8- cluster into a [Ag₄₉Mo₁₀@(TC4A)₆] cage, representing the first polyoxometalate-templated Ag cluster protected by calixarene macrocyclic ligands. The solution stability and photoelectric properties of {Ag49Mo16} are discussed. Furthermore, this POM-templated Ag nanocluster realized electrocatalytic CO₂ reduction applications, and 44.75% CO faradaic efficiency (FE) was obtained at a voltage of -0.8 V (vs. RHE).

Ancillary ligand-regulated Ti(IV)-based metallocalixarene coordination cages for photocatalytic H2 evolution

High-valence Ti(IV)-based metallocalixarene coordination cages that are linked by oriented ancillary ligands are unknown so far. Herein, the first family of tunable calixarene-based coordination cages of Ti(IV) with a framework formula [Ti₁₂(OⁱPr)₁₂(TBC[4])₆L₆] have been assembled from six {Ti₂(OⁱPr)₂(TBC[4])}²⁺ nodes and six pyridinedicarboxylic ligands. Furthermore, the {Ti12L6} cage showed strong photocatalytic H₂ evolution activity, and DFT studies were performed to explore its electronic structure.

Heterometallic Polyoxotitanium Clusters as Bifunctional Electrocatalysts for Overall Water Splitting

Incorporating heterometal into titanium-oxygen clusters (TOCs) is an effective way to improve its catalytic activity. Herein, we synthesize three novel heterometallic TOCs with the formula of [Ti₆Cu₂O₇(Dmg)₂(OAc)₄(ⁱPrO)₆][H₂Ti₆Cu₂O₇(Dmg)₂(OAc)₄(ⁱPrO)₈] ({Ti₆Cu₂}), [Ti₈Cu₂O₉(Dmg)₂(OAc)₂(ⁱPrO)₁₂] ({Ti₈Cu₂}), and [Ti₁₀Co₂O₆(Dmg)₂(Pdc)₄(ⁱPrO)₁₈Cl₃] ({Ti₁₀Co₂}, DmgH₂ = dimethylglyoxime; PdcH₂ = pyridine-2,3-dicarboxylic acid) using dimethylglyoxime and different carboxylates as the synergistic ligands. By depositing the clusters {Ti₆Cu₂} and {Ti₁₀Co₂} on carbon cloth as electrodes, we investigated the electrocatalytic performance of TOCs for full water splitting for the first time. To reach a 10 mA cm^-2 current density in an alkaline solution, the {Ti₁₀Co₂}@CC electrode needs an overpotential as low as 120 and 400 mV for the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER), respectively. In addition, full water-splitting equipment with {Ti₁₀Co₂}@CC as a cathode and an anode need only 1.67 V to deliver a current density of 10 mA cm^-2. Our work confirmed the potential of noble metal-free TOCs as bifunctional cluster-based electrocatalysts for water splitting, and their activities can be tuned by doping with different metal ions.

An ultrastable Ti-based metallocalixarene nanocage cluster with photocatalytic amine oxidation activity

Polyhedral metallocalixarene nanocage clusters based on pure Ti(IV) ions are to our knowledge unknown hitherto. Herein we report the first Ti(IV)-based metallocalixarene nanocage cluster by assembling a [Ti₁₃O₁₄] cage with six t-butylcalix[4]arene molecules. Notably, the cluster exhibits extraordinary stability in high-concentration acid/alkali solutions and can act as a stable photocatalyst to catalyze the oxidation of ammonia to imines.

Cd-Doped Polyoxotitanium Nanoclusters with a Modifiable Organic Shell for Photoelectrochemical Water Splitting

Incorporating heterometal and chromogenic groups into the titanium oxo cluster (TOC) nanomaterials is one of the effective strategies for the development of new high-performance photoelectrically active materials. In this Article, we report the structures and photoelectrochemical (PEC) performances of a family of TOCs, including pure [Ti₁₂O₈(OEt)₁₆L₈] ({Me-Ti₁₂}) and six Cd-doped clusters formulated as [H₄Cd₂Ti₁₀O₈(OEt)₁₆(L)₈(H₂O)₂] ({Cd₂Ti₁₀}; L = salicylic acid and their derivatives). The six Cd-doped clusters are isostructural, containing the same {Cd₂Ti₁₀O₈} core, but are protected by salicylic ligands modified with different functional groups. The compositions, structures, and solution stability of these clusters have been studied in detail by single-crystal X-ray diffraction and electrospray ionization mass spectrometry measurements. The embedding of heterometallic Cd(II) and chemical modification of organic protective shells can effectively regulate the PEC water oxidation activity of those clusters, with {F-Cd₂Ti₁₀} having the highest turnover number of 518.55 and the highest turnover frequency of 172.85 h^-1. Our work highlights the potential of using TOCs that do not contain noble metals as water oxidation catalysts, and their catalytic activity can be regulated by structural modification.

[Two cases report of laryngeal malignant melanoma and a review of literatures]

Summary Two patients both complained of one year history of hoarseness and the clinical manifestations and imageology among 2 patients were lack of specificity. The pathological tissue was successfully eradicated by surgical removal. Histopathology established laryngeal malignant melanoma as the diagnosis. The clinical manifestations and imageology were lack specificity between laryngeal malignant melanoma, laryngeal cancer and other malignant tumor, the diagnosis is difficult, often confirmed by postoperative pathology, the treatment is often by surgery and have a poor prognosis.

[The outcome of trial of labor after cesarean section]

Objective: To explore the outcome of trial of labor after cesarean section(TOLAC). Methods: Totally 614 TOLAC were conducted in the First Affiliated Hospital of Kunming Medical University from July 2013 to June 2016. Among them, 586 cases of singleton pregnancy with one prior cesarean section(gestational age≥28 weeks)were studied retrospectively. The maternal and neonatal outcomes among the vaginal birth after cesarean(VBAC)group(481 cases), failed TOLAC group(105 cases)and the elective repeat cesarean section(ERCS)group(1 145 cases)were compared. Multiple logistic regression was used to determine the risk factors of admission to neonatal intensive care unit(NICU). Results: (1)The TOLAC rate was 29.62%(614/2 073)from July 2013 to June 2016, and the VBAC rate was 82.6%(507/614). The cesarean section rate was reduced by VBAC by 3.147%(507/16 112).(2)The comparison of adverse maternal outcomes: in the VBAC group, the postpartum hemorrhage volume was(431±299)ml, the rate of postpartum fever was 6.4%(31/481), the birth weight of the neonates was(3 085± 561)g, and the rate of large for gestational age was 2.9%(14/481). All were significantly lower than those in the failed TOLAC group and the ERCS group(P<0.05). There was no significant difference in other adverse maternal outcomes[the uterine rupture rate(0.2% ,1/481), the bladder injury rate(0), the proportion of postpartum hemorrhage volume≥1 500 ml(1.0%, 5/481), the blood transfusion rate(3.7%, 18/481)]and adverse perinatal outcomes[the rate of neonatal 5-minute Apgar score<7(0.4%, 21/481), the rate of umbilical arterial pH<7.0(0.6% , 3/481), the rate of the NICU admission and the perinatal mortality rate(12.3%, 59/481)]among the 3 groups(P>0.05). Multiple logistic regression showed no association between VBAC and admission to the NICU(OR=0.84, 95%CI: 0.58-1.21). The isolated risk factors for admission to the NICU were preterm birth(OR=16.71, 95% CI: 11.44-24.40), hypertensive disorder complicating pregnamcy(OR=3.89, 95% CI: 2.39-6.35), meconium stained amniotic fluid(OR=2.48, 95% CI: 1.62-3.80), small for gestational age(OR=2.00, 95% CI: 1.19-3.36)and diabetes mellitus(OR=1.69, 95% CI: 1.14-2.50). Conclusions: VBAC reduces cesarean section rate, with good outcomes in both mother and neonate. It is a safe and feasible way of labor in women with only one cesarean section history.

Early third trimester maternal response to glucose challenge and pregnancy outcome in Chinese women-relationship between upper distribution level and recommended diagnostic criteria

BACKGROUND/OBJECTIVES

The objective of this study was to examine the relationship between upper distribution levels of glucose values in the 75-g oral glucose tolerance test (OGTT) and recommended diagnostic criteria for gestational diabetes mellitus (GDM) and adverse pregnancy outcomes.

SUBJECTS/METHODS

The distribution of the OGTT 2-h values of 13,501 pregnant women, which were below the World Health Organization (WHO) threshold for overt diabetes mellitus (DM), and managed in one teaching hospital in China, was reviewed and related to maternal characteristics and pregnancy outcomes.

RESULTS

For the entire group, the 90th and 95th percentile values of the OGTT 2-h glucose level, respectively, were close to the diagnostic cutoff values of the WHO and International Association of Diabetes and Pregnancy Study Groups (IADPSG) criteria. For adverse maternal outcomes, glucose level above the 90th percentile value was associated with increased hypertensive disorders, whereas no difference was seen with cutoff using the 95th percentile value. For perinatal outcomes, the 90th percentile was associated with increased neonatal intensive care unit admission and hypoglycemia, whereas the 95th percentile showed in addition association with phototherapy for jaundice and 5th-minute Apgar score <7. Although no differences in the incidence of adverse pregnancy outcomes were found using the different cutoffs, the >95th percentile cutoff value would have missed out 33.3-56.7% of the cases of adverse outcomes that would otherwise have been attributed to GDM.

CONCLUSIONS

Further studies are warranted to clarify which diagnostic criterion is most appropriate universally to identify adverse pregnancy outcomes attributed to GDM, and which could be mitigated with treatment specific for GDM.

Microinvasive Nd:YAG laser therapy of early glottic carcinoma and its effect on soluble interleukin-2 receptor, interleukin-2, and natural killer cells

OBJECTIVE

To investigate the effectiveness of microinvasive Nd:YAG laser therapy in human glottic Tis and T1 carcinomas, as well as its effect on the cellular immune function of the tumor-bearing hosts.

STUDY DESIGN

We treated 34 patients with microinvasive Nd:YAG laser therapy and evaluated its effect on the cellular immune function of the host.

METHODS

Thirty-four patients with glottic Tis or T1 squamous cell carcinoma were treated with fiberoptic laryngoscopic Nd:YAG laser surgery. Both before and after therapy, serum levels of soluble interleukin-2 receptor (SIL-2R) and interleukin-2 (IL-2), as well as natural killer (NK) cell activity, were determined by means of double-antibody sandwich technique, tritiated thymidine-deoxyribonucleoside incorporation, and iodine 125-uridine-deoxyribonucleoside release technique, respectively.

RESULTS

All 34 patients tolerated the procedure well. A 3- to 7-year follow-up in a subgroup of 27 patients resulted in an estimated cure rate of 85.2% (23 of 27 patients). In all 27 patients with a regular follow-up, a subjective improvement of phonation was noted after therapy to various degrees. In 74% (20 of 27 patients), voice and speech subjectively recovered to almost normal levels. The post-therapy serum levels of SIL-2R were significantly declined (P <.001), whereas those of IL-2 and the NK activity were significantly elevated (P <.001) as compared with those detected before therapy.

CONCLUSIONS

Therapy with fiberoptic laryngoscopic Nd:YAG laser surgery is simple, safe, effective and only minimally invasive for patients with glottic Tis or T1 carcinoma. At the same time, it has an immunoenhancing effect on its host.

[Research on automatic diagnosis system of electrocardiogram]

The duration of QRS wave, P wave and T wave of ECG can be computerized and auto-detected with digital signal process and wave recognition technology. It can diagnose 15 kinds of abnormal ECG such as ventricular presystole automatically and print out corresponding diagnosis reports. In order to verify the system's stability and creditability, we used American MIT-BIH database to test our algorithms and got a good result.

[Cloning and function of sanJ--a gene involved in nikkomycins biosynthesis of Streptomyces ansochromogenes]

A 7.5 kb DNA fragment was identified from the cosmid library of Streptomyces ansochromogenesus using a partial DNA fragment involved in the nikkomycin biosynthesis as a probe. It was cloned into pBluescript M13- and the resulting recombinant plasmid was designated as pNL2200. The nucleotide sequence of 2.3 kb Sal I -BamH I DNA fragment was determined and analysed. The result indicated that the fragment contains one complete open reading frame (ORF); The start codon is GTG at 271 position and the stop codon is TGA at 1,954 position. It contains 1,686 base pairs and encodes a protein with 561 amino acids. The deduced product has 44% identity with the ligase belong to the superfamily of adenylate-forming enzyme. The experiment of gene disruption showed that the sanJ gene was closely related to nikkomycins biosynthesis of Streptomyces ansochromogenes. It was designated as sanJ.

[MDM2 gene expression in nasopharyngeal carcinoma and its relationship with p53 protein expression and EB virus latent infection]

OBJECTIVE

To define the expression levels of MDM2 gene in nasopharyngeal carcinoma (NPC) and its relationship with p53 protein expression and EB virus latent infection.

METHOD

MDM2 gene expression at mRNA and protein levels, p53 protein and EB virus DNA were detected by nonradioactive in situ hybridization (ISH), immunohistochemistry(IHC) and polymerase chain reaction (PCR) separately in 46 cases of NPC tissues and 12 cases of chronic inflammation of nasopharyngeal epithelium (CINE).

RESULT

Fourteen cases of NPC showed MDM2 mRNA and protein overexpression, 38 cases were p53 protein positive, and 43 cases were EBV-DNA positive. Neither MDM2 nor p53 protein was expressed in any case of CINE. MDM2 expression was significantly related to p53 protein expression (P < 0.05), but not to EB virus latent infection in NPC.

CONCLUSION

MDM2 gene may play an important role in the pathogenesis of NPC through interacting with p53 protein.

[MDM2 gene amplification and overexpression in nasopharyngeal carcinoma]

MDM2 gene amplification and overexpression were detected by DNA dot blot analysis and reverse transcription-polymerase chain reaction (RT-PCR) in 32 cases of nasopharyngeal carcinoma (NPC), 10 cases of chronic inflammation of nasopharyngeal epithelium(CINE) and NPC cell line HONE1. One case of NPC showed MDM2 gene amplification, NPC cell line HONE1 and ten cases of NPC showed MDM2 mRNA overexpression. No MDM2 gene amplification and overexpression were found in CINE. MDM2 mRNA overexpression was significantly related to cervical lymph node metastasis, but not to T stage of NPC. The results indicate that MDM2 gene may play an important role in the pathogenesis and the process of metastasis of NPC.

A comparison of 99Tcm-MIBI myocardial SPET and electron beam computed tomography in the assessment of coronary artery disease in two different age groups

The aim of this study was to compare the clinical value of 99Tcm-MIBI single photon emission tomography (SPET) and electron beam computed tomography (EBCT) in the assessment of coronary artery disease (CAD) in different age groups. 99Tcm-MIBI SPET (stress-rest), EBCT and coronary angiography studies were performed in 64 consecutive patients with suspected CAD. The patients were classified into two groups: Group A = 40 patients > 45 years of age and Group B = 24 patients < or = 45 years of age. There were 31 and 14 patients with coronary stenosis > or = 50% as determined by coronary angiography in Groups A and B, respectively. All patients (30 cases) with abnormal 99Tcm-MIBI myocardial SPET and coronary calcification detected by EBCT had significant coronary artery disease, and 93.3% of the patients with normal 99Tcm-MIBI SPET and normal EBCT had normal coronary angiography or < 50% lumen narrowing of the coronary arteries. In Group B, the sensitivity of SPET for detecting CAD was significantly higher than that of EBCT (92.9 vs 42.9%, P < 0.01); the specificity of SPET was comparable to that of EBCT. In Group A, there was no significant difference between SPET and EBCT in terms of sensitivity (93.6 vs 90.3%) or specificity (88.9 vs 55.6%). However, in the detection of individual coronary artery disease, the specificity of SPET was significantly higher than that of EBCT in Group A (94.1 vs 66.7%, P < 0.001). The sensitivity of SPET was again significantly higher than that of EBCT (85.7 vs 38.1%, P < 0.005) in Group B. The accuracy of SPET was higher than that of EBCT in both groups (82.5 vs 67.5%, P < 0.01 in Group A; 93.1 vs 76.4%, P < 0.01 in Group B, respectively). We conclude that 99Tcm-MIBI myocardial perfusion SPET has a higher sensitivity than EBCT in the detection of CAD in patients < or = 45 years old and a higher specificity in patients > 45 years of age. A combination of SPET and EBCT may assess CAD more accurately.

[Development of a multi-channel physiological telemetry system]

OBJECTIVE

To develop an instrument used in measurement of physiological parameters in laboratories or field. Method A: computer was used to process data in the telemetry system. The frequency-time division modulation technique was adopted. The low frequency signals were directly connected to the computer serial port after demodulation, and measurement control was achieved by single-chip computer. Temperature measurement results were obtained by conversion table.

RESULT

It is capable of telemeter and processing ECG, wind speed and temperature signals in real-time. Good results were gained in high temperature condition and -17 degrees C environment.

CONCLUSION

The instrument has many advantages, such as high accuracy, good processing ability, reliability, long operation distance, small volume and easy operation.

Effect of photodynamic therapy on selected laboratory values of patients with nasopharyngeal carcinoma

We determined pre- and post-photodynamic therapy (PDT) serum levels of soluble interleukin-2 receptor (SIL-2R) and interleukin-2 (IL-2), as well as activity of natural killer (NK) cells, among 24 patients with either persistent or recurrent nasopharyngeal carcinoma (NPC), using a double-antibody sandwich technique, tritiated thymidine-deoxyribonucleoside incorporation, and iodine 125-uridine-deoxyribonucleoside release techniques, respectively. The results showed that the post-PDT serum level of SIL-2R had significantly declined (p < .0005), while that of IL-2 and the NK cell activity had significantly increased (p < .0005), compared with pre-PDT values, suggesting an immunoenhancing effect of PDT on NPC patients.

[Genital condyloma acuminata: report of 63 cases]

Sixty-three cases of condyloma acuminata were treated from Aug. 1986 to May 1989. There were 44 males and 19 females. The age ranged from 17 to 55. The illness is a sexually transmitted disease. The etiology, diagnosis, management and prognosis were discussed.