Interaction of smoking and aging on emphysema and small airways disease in asymptomatic healthy men by CT-based parametric response mapping analysis

AIM

To explore whether small airway disease and emphysema were affected by the interaction between smoking and aging on chest computed tomography (CT) images of asymptomatic healthy men analysed using a quantitative imaging tool parametric response mapping (PRM).

MATERIALS AND METHODS

In this retrospective study, 95 asymptomatic healthy men underwent biphasic chest CT. The PRM classifies lung as a percentage of normal (PRMNormal%), functional small airway disease (PRMfSAD%), and emphysema (PRMEmph%). The patients were divided into groups based on their age and smoking status. Multiple linear regression analysis was applied to explore the factors influencing lung injury. Simple effects analysis was performed to explore the interaction between different age groups and smoking status.

RESULTS

The interaction between aging and smoking significantly affected PRMfSAD% and PRMEmph% (p<0.001). The age range 60-69 and smoking were associated with increased PRMfSAD% and PRMEmph% (p<0.05). Futher stratification into different age subgroups showed that smoking was associated with increased PRMfSAD% and PRMEmph% in the 50-59 year age group. Besides, smoking in the 50-59 and 60-69 years group was associated with decreased PRMNormal%, while smoking in the 60-69 years group did not significantly influence the prevalence of PRMfSAD% and PRMEmph% (p>0.05).

CONCLUSIONS

PRM reveals the interplay between smoking and aging in the development of lung injury in asymptomatic healthy men. Aging and smoking are important factors of emphysema and small airway disease in the 50-69 years group. In the 60-69 years group, aging poses a greater risk of lung injury compared to smoking.

[Analysis of discordance between HbA1c and FPG criteria for dysglycemia screening in physical examination individuals]

The general data, blood routine, liver and kidney function, glucose metabolism and lipid metabolism of 11 922 participants who underwent physical examination at the Health Management Center of the Second Xiangya Hospital of Central South University from January 2019 to December 2019 were collected. Clinical characteristics and independent factors of patients with discordance between HbA1c and FPG were evaluated and analyzed. The prevalence of HbA1c-defined diabetes and prediabetes (respectively 8.13%, 34.79%) were significantly higher than that in FPG-defined diabetes and prediabetes (respectively 4.70%, 8.97%) (χ²=2 635.940;P<0.001). The prevalence of inconsistence between HbA1c and FPG was 35.65% and increased with increasing age. This inconsistence mainly occurred in population with HbA1c:5.7%-6.0% and FPG<5.6 mmol/L, followed by population with HbA1c:6.1%-6.4% and FPG<5.6 mmol/L. The risk factors of inconsistency included advanced age, overweight or obesity, hypoalbuminemia, dyslipidemia and hyperuricemia. Among these special participants, compared with participants under 45 years old, participants with over 45 years of age (OR=3.525, 95%CI: 3.216-3.863, P<0.001) were more likely to have inconsistence between HbA1c and FPG; and overweight participants (OR=1.474, 95%CI: 1.341-1.620, P<0.001) or obese participants (OR=1.856, 95%CI: 1.633-2.110, P<0.001) are prone to have the inconsistence than those with normal weight.

[Assessment of the burden of clonorchiasis and its temporal changes in China]

OBJECTIVE

To assess the burden of clonorchiasis and identify its temporal and spatial changes in China, thus to provide insights into the control and prevention of the diseases.

METHODS

The disability-adjusted life years (DALYs) was employed as the primary indicator for the disease burden. The prevalence data of Clonorchis sinensis infection were obtainted from the three national surveys on important human parasitic diseases in China, conducting during the period from 1988 to 1922, from 2001 to 2004 and from 2014 to 2016, respectively, and the demographic data from National Bureau of Statistics of China. DALYs of clonorchiasis were calculated and the temporal changes were analyzed at both national and provincial levels, using the disability weight (DW) obtained from a community study in China. Sensitivity analysis was carried out to compare the resulted DALYs of China calculated under the method adopted in this study and that calculated with other commonly used methods.

RESULTS

The national burden of clonorchiasis was 489174.04 [95% confidence interval (CI): (391648.87, 597509.87)] DALYs in China in 2016, indicating 0.36 [95% CI: (0.28, 0.43)] DALYs per 1 000 populations. The regions with a high burden of clonorchiasis were concentrated in southern China and northeastern China, and the provinces with the three highest burdens of clonorchiasis included Guangxi Zhuang Autonomous Region, Guangdong Province and Heilongjiang Province, which accounted for 91.18% of total burdens of clonorchiasis in China. During the periods of the three national surveys on important human parasitic diseases in China, the national burden of clonorchiasis was found to show a tendency of first rise and then decrease in China; however, the burden of clonorchiasis has recently shown a tendency towards a rise in Guangxi Zhuang Autonomous Region, Heilongjiang Province and Jiangxi Province. Sensitivity analysis showed that the calculation of diseases burden with age-stratified prevalence of clonorchiasis was similar to that of our method without age stratification; however, the burden estimates calculated only based on the DW of the severe symptoms were much lower than our estimates.

CONCLUSIONS

The burden of clonorchiasis is high in China, with a large regional difference. Recently, the overall burden of clonorchiasis has shown a tendency of decline in China; however, there is a tendency towards a rise in some provinces. Therefore, the control of clonorchiasis requires more adaptations to local circumstances.

Local infiltration analgesia in primary total knee arthroplasty

INTRODUCTION

Postoperative pain in total knee arthroplasty (TKA) can hinder rehabilitation and cause morbidity. Local infiltration analgesia (LIA), comprising an anaesthetic drug, non-steroidal anti-inflammatory drug, and adrenaline, has been introduced to reduce pain and systemic side-effects. This study evaluated the efficacy of LIA in TKA with respect to morphine consumption and postoperative pain score.

METHODS

This single-centre retrospective cohort study recruited patients with knee osteoarthritis who were scheduled for primary TKA during the period from January 2017 to December 2017. Patients with chronic inflammatory joint disease, contra-indications for LIA, or dementia were excluded. Patients in the LIA group were administered single-dose LIA intra-operatively, while those in the control group were not. Primary outcomes were postoperative pain score, morphine demand, and morphine consumption; secondary outcomes were range of motion, quadriceps power, and postoperative length of stay.

RESULTS

In total, 136 patients were recruited (68 per group). Total postoperative morphine demand and consumption, as well as pain scores from postoperative day (POD) 1 to POD 4, were lower in the LIA group than in the control group. The range of motion from POD 1 to POD 4 and quadriceps power on POD 1 were higher in the LIA group than in the control group. Quadriceps power from POD 2 to POD 4 and postoperative length of stay were not significantly different between groups.

CONCLUSIONS

Intra-operative single-dose LIA can effectively reduce postoperative pain, morphine demand, and morphine consumption. Therefore, the use of LIA is recommended during TKA.

[Complex enzyme combined with ultrasound extraction technology, physicochemical properties and antioxidant activity of Hedysarum polysaccharides]

In this study, complex enzymes combined with ultrasonic extraction technology（MC） were used, to select optimal extraction combinations by single factor and orthogonal test, with Hedysarum polysaccharides yield and content as the comprehensive indexes. The components, physicochemical properties and antioxidant activity of Hedysarum polysaccharides from complex enzyme combined with ultrasonic extraction（HPS-MC）and the Hedysarum polysaccharides from hot water extraction（HPS-R）were analyzed. The results showed that：complex enzymes had significant effect on the yield and content of Hedysarum polysaccharides, and the ultrasonic power could significantly improve the content of Hedysarum polysaccharides. The optimum technological parameters were as follows: complex enzyme ratio 1:1, ultrasonic power 105 W, ultrasonic time 60 min, and enzymatic hydrolysis pH 5, achieving （14.01±0.64）% and （92.45±1.47）% respectively for the yield and content of Polysaccharides. As compared with HPS-R, the molecular weight, absolute viscosity and protein content of HPS-MC were decreased, while the content of uronic acid was increased. In the antioxidant system, the concentration of polysaccharide was within the range of 1-7 g·L⁻¹; the antioxidant activity of HPS-MC was higher than that of HPS-R, and HPS-MC (80%) with the lowest molecular weight showed a significant dose effect relationship with the increase of the experimental concentration. In conclusion, MC is a simple, convenient, economical and environmentally friendly extraction technology, and the Hedysarum polysaccharides extracted by this method have obvious antioxidant activity.

Highly enhanced adsorption of Congo red by functionalized finger-citron-leaf-based porous carbon

A novel high-performance porous carbon material, lanthanum(III)-doped finger-citron-leaf-based porous carbon (La/FPC), has been synthesized and used as an adsorbent for anion dye Congo red (CR). The La/FPC was characterized by nitrogen adsorption and desorption isotherms, scanning electron microscopy, transmission electron microscopy and X-ray photoelectron spectroscopy. The adsorption performance of CR by the FPC and La/FPC composites with different contents of lanthanum(III) were evaluated in fixed-bed breakthrough experiments and batch tests at room temperature (298 K). The La/FPC had a high CR uptake capacity, which was superior to those previously reported for other adsorbents. The La/FPC sorbents can be easily regenerated using an ethanol elution technique, and after five cycles the reused La/FPC maintained about 98% of its original CR adsorption capacity. The adsorption kinetics of CR onto the lanthanum(III)-doped FPCs followed a pseudo-second-order kinetic model and fitted well with a Langmuir adsorption isotherm. La/FPC is a promising adsorbent for the removal of the anionic dyes from wastewater.

Efficient optical coupling in AlGaN/GaN quantum well infrared photodetector via quasi-one-dimensional gold grating

In this letter, a new kind of grating, quasi-one-dimensional gold grating, has been proposed to enhance the optical coupling in AlGaN/GaN quantum well infrared photodetector (QWIP). The electric field distribution, current density and energy flow are analyzed by an algorithm of finite element method (FEM). Significantly enhanced electric field component E(z) perpendicular to multiple quantum wells (MQWs) is explained by introducing the resonant coupling of surface plasmon polariton (SPP) and localized surface plasmon (LSP). The |E(z)|(2) in MQWs reaches 0.85 (V/m(2) when the electric field intensity (|E(0)|(2)) of normal incidence is 1 (V/m(2) at 4.65 μm, showing 2 times and 1.3 times increase compared with that obtained via a one-dimensional gold grating and a two-dimensional gold grating, respectively. The results confirm that the quasi-one-dimensional gold grating provides more plasma excitation source and higher charge density with structure optimization, resulting in a high optical coupling efficiency of 85% in quantum well region.

Double-resonance enhanced intersubband second-order nonlinear optical susceptibilities in GaN/AlGaN step quantum wells

Second-order nonlinear optical susceptibilities for second harmonic generation (SHG) associated with intersubband transitions in GaN/AlGaN single quantum well and step quantum well have been studied theoretically by solving Schrödinger and Poisson equations self-consistently. The calculated results suggest that due to the very large polarization-induced field in the quantum well, the potential profile becomes asymmetrical, leading to large second-order susceptibilities. A high value about 4 × 10^-7 m/V can be obtained in single quantum well structure. Furthermore, by adopting step quantum well structure to increase the asymmetry degree of the potential profile and manipulate the energy levels for double-resonance, a significant enhancement of second-order susceptibility can occur in step quantum well. Specifically, the susceptibility can be as large as 4 × 10^-6 m/V with structure optimization, about an order of magnitude greater than that in single quantum well. The results indicate that nonlinear optical elements based on GaN/AlGaN step quantum wells are very promising for SHG in a wide range of wavelengths from telecommunication to mid-infrared, especially effective in longer wavelength.

Prospective cross-sectional study using questionnaire to assess the effect of a different nomenclature for psychiatric illnesses on the perception of these diseases by university students

OBJECTIVE. To assess the effect of a difference in nomenclature for psychiatric illness on perceptions of university students. DESIGN. Cross-sectional study. SETTING. Three local universities in Hong Kong. PARTICIPANTS. A total of 201 university students (undergraduates or postgraduates) were interviewed with a questionnaire. MAIN OUTCOME MEASURES. Score difference between the new and old nomenclature of each disease for each question of the questionnaire, using a 5-point Likert scale and an integrated score difference for each disease. RESULTS. Of the seven diseases investigated, six yielded a significant yet mild increase in positive perceptions with the new nomenclature. These diseases included schizophrenia (integrated score difference: +0.158, P<0.001), neurasthenia (integrated score difference: +0.117, P<0.001), paranoia (integrated score difference: +0.209, P<0.001), personality disorder (integrated score difference: +0.282, P<0.001), attention deficit hyperactivity disorder (integrated score difference: +0.086, P=0.005), and bipolar disorder (integrated score difference: +0.154, P<0.001). Epilepsy showed a negative perception with its new nomenclature (integrated score difference: -0.119, P<0.001). CONCLUSIONS. The new nomenclature system for psychiatric diseases achieves more positive perceptions among the university students than the old nomenclature. Epilepsy was the exception for which the old nomenclature conferred a more positive perception. Further studies on this topic involving a more general population should be advocated to confirm the improvements in perception with the new naming system for psychiatric diseases.

[Comparison for removing Cu2+ by micellar-enhanced ultrafiltration with SDS and SDBS]

Micellar-enhanced ultrafiltration was used to remove Cu2+ (Cu2+ was fixed at 0.6 mmol/L) from simulant aqueous solutions with SDS and SDBS as anionic surfactants respectively. Compare SDS and SDBS separation through permeate flux, permeate concentration, rejection and enrichment ratio. Experimental results show that the average permeate flux with SDS is always higher than that with SDBS [the average flux with SDS is 29.92 L x (m2 x h)(-1), while that with SDBS is only 16.55 L x (m2 x h)(-1)], the permeate concentration of SDS is always lower than that with SDBS. When the permeate concentration of Cu2+ close to zero, 2 mmol/L and 6 mmol/L of SDBS and SDS are respectively required. Cu2+ rejection and enrichment ratio with SDS are always higher than those with SDBS (the average Cu2+ rejection and enrichment ratio with SDS are respectively 85.06% and 4.18, while those with SDBS are 69.05% and 4.05 respectively). Besides, the average enrichment ratio of SDS is also higher than that of SDBS (SDS is up to 3.89, while SDBS is 3.13). Therefore, SDS is more suitable than the SDBS for removal of Cu2+.

Effect of groups difference in surfactant on solubilization of aqueous phenol using MEUF

Micellar-enhanced ultrafiltration (MEUF) was used to remove phenol from simulant aqueous solutions. The effect of groups difference of cationic surfactant on the solubilization of phenol was investigated through orthogonal experiment, namely, surfactants with the same length of hydrocarbon chain but different hydrophilic head group and vice versa. The effects on the solubilization of phenol of various operating parameters in the practical application of MEUF with OTAB were studied, including surfactant concentration, electrolyte concentration, feed phenol concentration, operating pressure, temperature, respectively. The results showed that the rejection of phenol increased in the order as follows: cetyltrimethylammonium bromide (CTAB)<octadecyl trimethyl ammonium bromide (OTAB)<cetylpyridinium chloride (CPC). With the introduction of feed surfactant concentration, the retention recovery of phenol increased. Electrolyte concentration, feed phenol concentration, operating pressure and temperature all had a slight influence on the retention of phenol.

[Recovery of Cd2+ by an electrolytic process from the concentrated solution of micellar enhanced ultrafiltration]

Micellar enhanced ultrafiltration (MEUF) is a new method which is based on the surfactant of the unique characteristic of parental molecular structure that can remove heavy metals in the water. The concentrated solution by dealing with the MEUF contains high concentration of heavy metal ions, so it must be need for further processing. The electrolysis method was employed to recovery Cd2+ from the concentrated solution of micellar enhanced ultrafiltration (MEUF). Effects of type of electrode, electrolysis voltage (U) and time (t), solution pH, surfactant to Cd2+ molar ratio ([SDS]/[Cd2+]) on Cd2+ recovery efficiency were investigated. The study found that the surfactant had some effect of resistance to electrolysis process. The optimum experimental conditions were obtained: stainless steel (anode)-graphite (cathode), U = 2.8 V, t = 100 min, pH = 4, [SDS]/[Cd2+] = 5 ([SDS] = 8.5 mmol/L constant). And the recovery efficiency of Cd2+ in the concentrated solution was 50.26%.

[Recovery and reuse of SDS by ultrafiltration with acid or chelator]

The retentate stream containing Cd2+ was chosen for the investigation. Effects of acid reagent, chelator, pH and operation mode on separation of Cd2+ and recovery of SDS, as well as efficiency of reclaimed SDS were investigated. The optimum conditions in acidification were obtained: H2SO4 as acid reagent, pH = 1.0, operation mode of batch. Under these conditions, separation of Cd2+ and recovery of SDS are 98.0% and 58.1%, respectively. And the efficiency of reclaimed SDS for removing Cd2+ is 80.2%. In chelation, the optimum conditions were investigated: EDTA as chelator, uncontrolled pH (pH = 4.4) and operation mode of batch. Under these conditions, separation of Cd2+ and recovery of SDS are 90.1% and 60.5%, respectively. And the efficiency of reclaimed SDS for removing Cd2+ is 79.4%.

Recovery of surfactant SDS and Cd2+ from permeate in MEUF using a continuous foam fractionator

The purpose of this study was to investigate the use of foam fractionation to recover valuable surfactant (SDS) and metal ion (Cd2+) in the permeate of micellar-enhanced ultrafiltration (MEUF). The effects of operating factors, such as time, air flow rate, feed flow rate, liquid height, foam height, feed surfactant concentration, ethanol concentration and temperature on separation characteristics were studied in the continuous operation. When the concentrations of surfactant (SDS) and metal ion (Cd2+) in the feed solution were 500 mg/L and 10 mg/L, an enrichment ratio of 3.1 was achieved for SDS along with 52% removal fraction, as well as 99.35% Cd2+ was removed, after optimization of different process parameters. As the optimized results, the air and liquid flow rates were 100 L/h and 5 L/h, liquid and foam heights were 45 cm and 66 cm, respectively, sparger pore size was 10 microm. The Cd2+ concentration in the effluent was lower than 0.1mg/L which could meet the integrated wastewater discharge standard (the first grade of national discharge standards in China).

Mechanism of measles virus failure to activate NF-kappaB in neuronal cells

Lack of IFN-beta and MHC class I expression in measles virus (MV) infected neurons could impair the host antiviral defense mechanism and result in virus escape from recognition by cytotoxic T-cells. Induction of IFN-beta and MHC class I gene expression requires NF-kappaB activation which depends on degradation of IkappaBalpha, an inhibitory protein of NF-kappaB. In earlier studies we demonstrated that in contrast to glial cells, MV was unable to induce IkappaBalpha degradation in neuronal cells. It is unclear whether this failure is due to the presence of a neuron-specific IkappaBalpha isoform or a defect in the MV signaling cascade that leads to IkappaBalpha phosphorylation and degradation. In this study, an IkappaBalpha-wild type (WT) expression vector was transfected into neuronal and glial cells and subsequently exposed to MV. In contrast to glial cells, IkappaBalpha-WT was degraded in neuronal cells in response to TNFalpha but not MV. The findings eliminate the existence of an IkappaBalpha isoform in neuronal cells that is resistant to phosphorylation by MV. Blocking de novo protein synthesis with cyclohexamide had no effect on neuronal IkappaBalpha, indicating that lack of degradation rather than increased synthesis is responsible for IkappaBalpha accumulation in MV-stimulated neuronal cells. To determine if malfunction in the MV receptor CD46 is responsible for failure of IkappaBalpha phosphorylation and degradation, neuronal cells were transfected with a wild type CD46 (CD46-WT) expression vector. MV stimulation of CD46-WT transfected cells failed to induce IkappaBalpha degradation. Collectively these findings indicate that failure of MV to phosphorylate neuronal IkappaBalpha is not due to a presence of an IkappaBalpha isoform or malfunction of the MV receptor, and is more likely to be due to a defect in the signaling pathway that normally leads to IkappaBalpha phosphorylation and degradation.

Origins of accessory small ring marker chromosomes derived from chromosome 1

Three patients with accessory small ring chromosomes derived from chromosome 1 are presented together with additional clinical details and cytogenetic analyses of a previously reported patient. Cytogenetic analysis was undertaken by FISH using a reverse painting probe generated from one of the patients by microdissection of the r(1) chromosome and with a BAC923C6 which maps to 1p12. Results indicated that patients with r(1) chromosomes consisting of 1q12 heterochromatin and short arm pericentric euchromatin which extends to at least the BAC923C6 were associated with a normal or mild phenotype. Patients with abnormal phenotypes possessed two types of rings. One patient had evidence for contiguous pericentric short arm euchromatin which extended from the centromere to beyond the BAC923C6. Two patients showed molecular cytogenetic results which were compatible with non-contiguous chromosome 1 euchromatin. The diversity of origin of r(1)s will hamper attempts to define phenotype/genotype relationships.

Failure of measles virus to activate nuclear factor-kappa B in neuronal cells: implications on the immune response to viral infections in the central nervous system

Neurons are postmitotic cells that foster virus persistence. These cells lack the HLA class I molecules required for clearance of infected cells. Previously, we showed that HLA class I is induced by measles virus (MV) on glial cells, which is primarily mediated by IFN-beta. In contrast, MV was unable to induce HLA class I or IFN-beta in neuronal cells. This failure was associated with lack of NF-kappa B binding to the positive regulatory domain II element of the IFN-beta promoter, which is essential for virus-induced IFN-beta gene activity. In this study, we demonstrate that the failure to activate NF-kappa B in neuronal cells is due to the inability of MV to induce phosphorylation and degradation of I kappa B, the inhibitor of NF-kappa B. In contrast, TNF-alpha induced degradation of I kappa B alpha in the neuronal cells, suggesting that failure to induce I kappa B alpha degradation is likely due to a defect in virus-mediated signaling rather than to a defect involving neuronal I kappa B alpha. Like MV, mumps virus and dsRNA failed to induce I kappa B alpha degradation in the neuronal cells, suggesting that this defect may be specific to viruses. Autophosphorylation of the dsRNA-dependent protein kinase, a kinase possibly involved in virus-mediated I kappa B alpha phosphorylation, was intact in both cell types. The failure of virus to induce I kappa B alpha phosphorylation and consequently to activate NF-kappa B in neuronal cells could explain the repression of IFN-beta and class I gene expression in virus-infected cells. These findings provide a potential mechanism for the ability of virus to persist in neurons and to escape immune surveillance.

High resolution characterization of an interstitial deletion of less than 1.9 Mb at 4p16.3 associated with Wolf-Hirschhorn syndrome

Wolf-Hirschhorn syndrome (WHS) caused by 4p16.3 deletions comprises growth and mental retardation, distinct facial appearance and seizures. This study characterized a subtle interstitial deletion of 4p16.3 in a girl with mild retardation and possessing facial traits characteristic of WHS. The patient had generalized seizures in conjunction with fever at 3 and 5 years of age. Fluorescence in situ hybridization (FISH) with a series of markers in the 4p16.3 region showed that the interstitial deletion in this patient was between the probes D4S96 and D4S182, enabling the size of the deletion to be estimated as less than 1.9 Mb. This is the smallest interstitial deletion of 4p16.3 which has been reported. The patient contributes to a refinement of the phenotypic map of the WHS region in 4p16.3. The critical region for the characteristic facial changes of WHS, failure to thrive and developmental delay is now localized to a region of less than 700 kb. The mental retardation of this patient was mild suggesting that small interstitial deletion may have less severe phenotypic consequences.

Improvement of schizophrenic symptoms and changes in plasma HVA concentrations, plasma anti-D2 and anti-5-HT2 receptor activities with clozapine

In order to investigate the biological mechanisms underlying the clinical efficacy of clozapine, 200 mg/day of clozapine was added to the drug regimens of 19 patients with chronic, anti-psychotic-resistant schizophrenia, and the plasma homovanillic acid (HVA), clozapine concentrations, anti-dopamine D2 and anti-serotonin 5-HT2 receptor activities were measured. After 28 days, six patients showed an improvement of more than 20% over baseline Brief Psychiatric Rating Scale (BPRS) scores. Mean plasma HVA concentrations and anti-D2 receptor activities did not change significantly in the entire group or in the six patients showing improvement. However, anti-5-HT2 receptor activities increased significantly in all 19 patients. Changes in BPRS scores did not correlate significantly with changes in plasma HVA or with changes in clozapine concentrations, or with anti-D2 and anti-5-HT2 receptor activities.

Mechanisms of small ring formation suggested by the molecular characterization of two small accessory ring chromosomes derived from chromosome 4

Molecular cloning of a microdissected small accessary ring chromosome 4 from a moderately retarded and dysmorphic patient has been performed to identify the origin of the ring chromosome. FISH was performed with cosmids identified with the cloned, microdissected products and with other markers from chromosome 4. The present study clearly demonstrates that the small ring in this patient originates from three discontinuous regions of chromosome 4: 4p13 or 14, the centromere, and 4q31. It is suggested that the origin of the ring chromosome is a ring involving the entire chromosome 4, which has then been involved in breakage and fusion events, as a consequence of DNA replication generating interlocked rings. A second severely retarded and dysmorphic patient also had a small accessary ring derived from chromosome 4. FISH studies of this ring are consistent with an origin from a contiguous region including the centromere to band 4q12. It is apparent that there are at least two mechanisms for the formation of small ring chromosomes. This adds a further complication in any attempt to ascertain common phenotypes between patients known to have morphologically similar markers derived from the same chromosome.

Functional characterization of the promoter region of the platelet-activating factor receptor gene. Identification of an initiator element essential for gene expression in myeloid cells

To understand the molecular mechanisms that direct the expression of the gene encoding the platelet-activating factor (PAF) receptor, the 5'-flanking region of the human PAF receptor gene was cloned, and its promoter activity in myeloid cell lines was characterized. By the 5'-rapid amplification of cDNA ends method and primer extension, the transcription initiation site was mapped to an adenosine residue 137 bases upstream of the ATG translation initiation codon. The promoter region lacks a typical TATA or CCAAT box. However, the sequence encompassing the transcription initiation site shows high homology to the initiator (Inr) sequence. Transfection of promonocytic U937 cells with recombinant plasmids containing a series of truncated segments of the 5'-flanking region linked to the luciferase reporter gene revealed that the sequence from nucleotides -44 to +27 relative to the transcription initiation site was sufficient to promote a high level of gene expression. The promoter activity was much lower in nonexpressing HeLa cells and promyelocytic HL-60 cells, which express relatively low levels of the PAF receptor. Gel mobility shift analysis demonstrated the binding of nuclear factors extracted from myelocytic cells to the -16/+18 sequence containing the Inr element. No binding activity was detected using the nuclear extracts from the nonmyelocytic HeLa cells. The DNA-protein complexes were sequence-specific since the binding was not significantly affected by the mutated Inr sequences or the Inr sequence of the terminal deoxynucleotidyltransferase gene. Furthermore, point mutations in the Inr element significantly reduced promoter activity in both U937 and THP-1 cell lines. When Me2SO or retinoic acid was used to induce granulocytic differentiation of HL-60 cells, a distinct Inr-protein complex was induced concurrently, but the complex was not observed in 12-O-tetradecanoylphorbol-13-acetate-induced monocytic differentiated HL-60 cells or Me2SO-induced differentiated U937 cells, indicating that the inducible Inr binding activity is granulocyte-specific. These results suggest that distinct nuclear factors interact with the unique Inr element and play a role in the transcriptional regulation of the PAF receptor in various myeloid cells.

Computer-aided three-dimensional reconstruction and measurement of bony and membranous labyrinth

We used three methods to reconstruct a same bony and membranous labyrinth by an image processing work station (IPWS). Three dimensional (3-D) models of the bony and membranous labyrinth were thus obtained. Different parts of the labyrinth were measured and the spatial relationship between the bony and membranous labyrinth was observed. Many 3-D parameters such as cochlear length, volume of different parts of the labyrinth, angles among the three semicircular canals were measured. The results of this experiment are useful in the study of the cochlear and vestibular function.

Epidemiologic characteristics of Clonorchiasis sinensis in Guandong Province, China

Extensive survey of the distribution of the liver fluke Clonorchis sinensis in Guandong Province, China, has revealed high frequencies in human populations in some areas and absence in others. The distribution relates in part to the demography of first and second intermediate hosts and animal reservoir hosts, but it relates more clearly to the differing food habits of various populations in particular geographic areas. Thus clonorchiasis is concentrated in the Zhu Jiang (Pearl River) delta and along the Han Jiang (Han River) but is absent in the Leizhou Peninsula and in the western region of the province. Males tend to have higher infection rates than females. Age distribution is not uniform: in some communities infection rates increase with age where adults eat raw or undercooked fish, while in other infections reaches its peak in early teenage children and declines thereafter where children eat small raw fish but the habit does not persist into adult life. While there is some evidence that high C. sinensis rates correlate with high liver cancer rates and vice versa, this issue requires in depth investigation at community level to differentiate hepatocellular carcinoma and early cholangiocarcinoma, since it is possible that C. sinensis infection promotes higher risk of the latter form of liver cancer.

[The role of ADP-cyclic AMP system in horseshoe crab amebocytes aggregation and gel formation]

A study of the effects of ADP and cyclic AMP related drugs on gel formation induced by endotoxin and amebocytes aggregation was conducted. The gel formation induced by endotoxin could be inhibited by ADP, cyclic AMP, ATP and aminophylline. Conversely, Phosphodiesterase enhanced gelation rate. A calmodulin antagonist, trifluoperazine, also inhibited endotoxin-induced gel formation, but this agent was able to induce potentiation in amebocytes aggregation. These results suggest that the cyclic AMP phosphodiesterase system may play an important role in endotoxin-induced gel formation, and it was concluded that, in the presence of both Ca++ and endotoxin, the calmodulin-like protein will activate the cyclic AMP phosphodiesterase system and decrease the concentration of cyclic AMP, thus promoting gel formation.