A compact radio-frequency ion source for high brightness and low energy spread negative oxygen ion beam production

A high brightness and low energy spread (∆E) ion source is essential to the production of a high-quality primary ion beam applied in secondary ion mass spectrometry (SIMS). A compact 13.56 MHz radio-frequency (RF) ion source with an external planar spiral antenna has been developed as a candidate ion source for the production of negative oxygen ion beams for SIMS application. This ion source is designed with a three-and-a-half-turn water-cooled planar antenna for RF power coupling, a multi-cusp magnetic field for effective plasma confinement, and a three-electrode extraction system. The experimental results show that more than 50 µA negative oxygen ion beams have been extracted, which consist of 56% O-, 25% O2-, and 19% O3-. The ion energy distribution of the negative oxygen ion beam exhibits a Gaussian distribution with a minimum ∆E of 6.3 eV. The brightness of the O- beam is estimated to be 82.4 A m-2 Sr-1 V-1. The simulation, design, and experimental study results of this RF ion source will be presented in this paper.

[Regulatory effects of the Nocardia rubra cell wall skeleton on the biological function of human neutrophils]

Objective: To investigate the regulatory effects and mechanism of Nocardia rubra cell wall skeleton (Nr-CWS) on the biological function of human neutrophils. Methods: The experimental research method was used. Fifteen healthy adult volunteers (7 males and 8 females, aged 24 to 45 years) were recruited from Suzhou Physical Examination Center for physical examination from May to October 2022, the peripheral venous blood was collected, and neutrophils were extracted by immunomagnetic bead sorting. The cells were divided into normal control group without any treatment, Nr-CWS alone group treated with Nr-CWS of final mass concentration 60 ng/mL alone, endotoxin/lipopolysaccharide (LPS) alone group stimulated with LPS of final mass concentration 1 μg/mL alone, and LPS+Nr-CWS group stimulated with LPS first and then treated with Nr-CWS as before. After 1 h of culture, the chemotaxis distance, chemotactic cell percentage, chemotactic index, maximum chemotactic speed, and chemotactic function score of neutrophils were detected using the modified agarose chemotactic model; the proportion and fluorescence intensity of phagocytosis cells, the level of reactive oxygen species (ROS), the protein expression levels of granular protein CD35, CD66b, and CD63, and the concentrations of inflammatory cytokines of interleukin 2 (IL-2), IL-4, IL-6, IL-10, IL-17A, tumor necrosis factor alpha (TNF-α), and interferon-γ in cell culture supernatant were detected by flow cytometry. The number of samples in each group in the above experiments was 15. Data were statistically analyzed with analysis of variance for factorial design and independent sample t test. Results: After 1 h of culture, the chemotactic function score of cells in normal control group, Nr-CWS alone group, LPS alone group, and LPS+Nr-CWS group were 15.0, 14.5±0.5, 1.5±0.5, 12.0±1.5, respectively. Compared with those in normal control group, the chemotaxis distance, chemotactic cell percentage, chemotactic index, maximum chemotactic speed, and chemotactic function score of cells were significantly decreased in LPS alone group and LPS+Nr-CWS group (with t values of 18.36, 18.88, 54.28, 18.36, 46.77, 10.58, 14.74, 6.84, 10.58, and 4.24, respectively, P<0.05); compared with those in LPS alone group, the five chemotactic function indexes as above in LPS+Nr-CWS group were significantly increased (with t values of 11.47, 14.65, 11.62, 11.47, and 13.75, respectively, P<0.05). After 1 h of culture, compared with those in normal control group, the proportion and fluorescence intensity of phagocytosis cells were significantly increased in Nr-CWS alone group (with t values of 6.86 and 6.73, respectively, P<0.05), and the above two indexes were significantly decreased in LPS alone group (with t values of 7.35 and 22.72, respectively, P<0.05) and LPS+Nr-CWS group (with t values of 21.37 and 13.10, respectively, P<0.05). After 1 h of culture, compared with that in normal control group, the level of ROS of cells in LPS alone group was significantly increased (t=6.64, P<0.05); compared with that in LPS alone group, the level of ROS of cells in LPS+Nr-CWS group was significantly decreased (t=5.46, P<0.05). After 1 h of culture, compared with those in normal control group, the protein expressions of CD35, CD66b, and CD63 of cells were significantly increased in LPS alone group and LPS+Nr-CWS group (with t values of 16.75, 17.45, 10.82, 5.70, 19.35, and 15.37, respectively, P<0.05); compared with those in LPS alone group, the protein expressions of CD35, CD66b, and CD63 of cells were significantly decreased in LPS+Nr-CWS group (with t values of 4.92, 5.72, and 3.18, respectively, P<0.05). After 1 h of culture, compared with those in normal control group, the concentrations of IL-2, IL-4, IL-6, IL-10, IL-17A, TNF-α, and interferon-γ in cell culture supernatant were significantly increased in LPS alone group (with t values of 22.10, 9.50, 7.21, 10.22, 24.88, 8.43, and 47.48, respectively, P<0.05), and the concentrations of IL-6, IL-10, IL-17A, TNF-α, and interferon-γ in cell culture supernatant were significantly increased in LPS+Nr-CWS group (with t values of 4.68, 5.12, 8.02, 5.58, and 7.13, respectively, P<0.05); compared with those in LPS alone group, the concentrations of IL-2, IL-4, IL-6, IL-10, IL-17A, TNF-α, and interferon-γ in cell culture supernatant were significantly decreased in LPS+Nr-CWS group (with t values of 5.39, 2.83, 5.79, 2.90, 5.87, 4.88, and 39.64, respectively, P<0.05). Conclusions: Nr-CWS can enhance the phagocytosis ability of neutrophils in normal condition and improve the chemotactic function, ROS level, degranulation protein level, and inflammatory factor level of human neutrophils in infectious condition. Nr-CWS can enhance the anti-infection ability of human neutrophils by regulating its biological behavior in innate immunity.

Heavy metal ions exchange driven protein phosphorylation cascade functions in genomic instability in spermatocytes and male infertility

DNA double-strand breaks (DSBs) are functionally linked to genomic instability in spermatocytes and to male infertility. The heavy metal cadmium (Cd) is known to induce DNA damage in spermatocytes by unknown mechanisms. Here, we showed that Cd ions impaired the canonical non-homologous end-joining (NHEJ) repair pathway, but not the homologous recombination (HR) repair pathway, through stimulation of Ser2056 and Thr2609 phosphorylation of DNA-PKcs at DSB sites. Hyper-phosphorylation of DNA-PKcs led to its premature dissociation from DNA ends and the Ku complex, preventing recruitment of processing enzymes and further ligation of DNA ends. Specifically, this cascade was initiated by the loss of PP5 phosphatase activity, which results from the dissociation of PP5 from its activating ions (Mn), that is antagonized by Cd ions through a competitive mechanism. In accordance, in a mouse model Cd-induced genomic instability and consequential male reproductive dysfunction were effectively reversed by a high dosage of Mn ions. Together, our findings corroborate a protein phosphorylation-mediated genomic instability pathway in spermatocytes that is triggered by exchange of heavy metal ions.

[A deep learning segmentation model for detecting caries in molar teeth]

This study aimed to build a home use deep learning segmentation model to identify the scope of caries lesions. A total of 494 caries photographs of molars and premolars collected via endoscopy were selected. Subsequently, these photographs were labeled by physicians and underwent segmentation training by using DeepLabv3+, and then verification and evaluation were performed. The mean accuracy was 0.993, the sensitivity was 0.661, the specificity was 0.997, the Dice coefficient was 0.685, and the intersection over union (IoU) was 0.529. Therefore, the present deep learning segmentation model can identify and segment the scope of caries.

[Prospective study on the analysis of intestinal microflora changes and prediction on metabolic function in severe burn patients at early stage by 16S ribosomal RNA high-throughput sequencing]

Objective: To analyze the changes of intestinal microflora and to predict the metabolic function of intestinal microflora in severe burn patients at early stage by 16S ribosomal RNA (rRNA) high-throughput sequencing. Methods: In this prospective observational study, 48 patients with severe burns who met the inclusion criteria were admitted to Department of Burns and Plastic Surgery of Affiliated Hospital of Jiangsu University from January 2018 to December 2019 were included in burn group, and 40 healthy volunteers who met the inclusion criteria and underwent physical examination at the Physical Examination Center of Affiliated Hospital of Jiangsu University in the same period were included in healthy group. Fecal samples were collected from patients in burn group in about 1 week after admission and from volunteers in healthy group on the day of physical examination. The 16S rRNA V4 gene sequencing was performed in the feces of patients in burn group and volunteers in healthy group to analyze the relative abundance of various bacteria. The operational classification unit (OTU) was divided by Mothur software to analyze the dominant bacteria. The OTU number, Chao1 index, Ace index, and Shannon index of fecal microflora were analyzed by QIIME1.9.0 software. The principal component analysis for relative abundance of fecal microflora was performed by Canoco Software 5.0. The metabolic function of fecal microflora was predicted by Kyoto Encyclopedia of Genes and Genomes. Data were statistically analyzed with independent sample t test, and Mann-Whitney U test, and Bonferroni correction. Results: The relative abundance of Bacteroides, Enterococcus, Acinetobacter, Macrococcus, and Staphylococcus in feces of patients in burn group was significantly higher than that of volunteers in healthy group (Z=-5.20, -2.37, -5.17, -4.41, -6.03, P<0.05 or P<0.01), and the relative abundance of unclassified-Helicobacillae, Prevotella, Cecobacteria, unclassified-Rumencocci, Pseudobutyrivibrio, Brautia, and unclassified-Digiestive Streptococcaceae (Z=-8.03, -3.21, -7.63, -5.88, -8.05, -8.05, -6.77, P<0.01) and other 12 species of bacteria in the feces of volunteers in healthy group was significantly higher than that of patients in burn group. The diversity of fecal microflora of volunteers in healthy group was better than that of patients in burn group, the main dominant microflora of volunteers in healthy group were Bacteroides, unclassified-Helicobacillae, Prevotella, unclassified- Enterobacteriaceae, Brautia, Parabacteroides, Escherichia coli, etc., and the main dominant microflora of patients in burn group were Bacteroides, Prevotella, unclassified-Enterobacteriaceae, and Parabacteroides. The OTU number, Ace index, Chao1 index, and Shannon index of fecal microflora of patients in burn group were 149±47, 199±45, 190±45, 2.0±0.9, which were significantly lower than 266±57, 323±51, 318±51, 3.8±0.5 of volunteers in healthy group (t=10.325, 11.972, 12.224, 11.662, P<0.01). The relative abundance of fecal microflora of patients in burn group and volunteers in healthy group was clearly divided into two groups by principal component 1, and the contribution rate of principal component 1 was 32.50%, P<0.01. The fecal microflora of volunteers in healthy group were more concentrated on principal component 2, the fecal microflora of patients in burn group were dispersed in principal component 2, and the contribution rate of principal component 2 was 13.44%, P>0.05. The metabolic levels of alanine-aspartate-glutamate, arginine- proline, cysteine-methionine, glycine-serine-threonine, phenylalanine, tryptophan, and tyrosine in amino acid, tricarboxylic acid cycle, glucose and mannose, galactolipin, glycolysis/gluconiogenesis, starch and sucrose in carbohydrate of fecal microflora of patients in burn group were significantly lower than those of volunteers in healthy group (Z=-4.75, -4.54, -4.75, -4.62, -3.71, -3.28, -4.19, -3.82, -4.72, -4.35, -4.75, -4.71, P<0.01). The levels of lipoic acid metabolism and coenzyme Q synthesis of fecal microflora of patients in burn group were significantly higher than those of volunteers in healthy group (Z=-6.07, -4.51, P<0.01). The metabolic level of arachidonic acid of fecal microflora of patients in burn group was similar to that of volunteers in healthy group (P>0.05). Conclusions: There are significant differences in intestinal microflora between severe burn patients at the early stage and healthy people, and the species and diversity of microflora are decreased, and the nutrient metabolism level is decreased in burn patients by 16S rRNA high-throughput sequencing.

Production of metallic ion beams by electron cyclotron resonance ion sources equipped with inductive heating ovens at the Institute of Modern Physics

A high-temperature oven based on the inductive heating technology was developed successfully at the Institute of Modern Physics in 2019. This oven features a durable operation temperature of over 2000 °C inside the tantalum susceptor. By carefully designing the oven structure, the material compatibility issue at high temperature has been successfully solved, which enables the production and routine operation of refractory metal ions with SECRAL-II (Superconducting Electron Cyclotron Resonance ion source with Advanced design in Lanzhou No. 2). To further apply this type of oven to the room temperature ECR ion sources LECR4 and LECR5 (Lanzhou Electron Cyclotron Resonance ion source No. 4 and 5), a mini-inductive heating oven has been fabricated and tested in 2020. By directly evaporating calcium oxide, some high charge state calcium beams have been produced successfully, such as 52 euA of ⁴⁰Ca¹⁶⁺, 30 euA of ⁴⁰Ca¹⁷⁺, and 12 euA of ⁴⁰Ca¹⁸⁺. The detailed design and testing results will be presented and discussed.

Influence of electron cyclotron resonance ion source parameters on high energy electrons

In order to diagnose the electron cyclotron resonance (ECR) plasma, a high-efficiency collimation system has been developed at the Institute of Modern Physics, and the bremsstrahlung spectra in the range of 10 keV-300 keV were measured on a third generation superconducting ECR ion source, SECRAL-II, with a CdTe detector. Used as a comparative index of the mean energy of the high energy electron population, the spectral temperature, T_s, is derived through a linear fitting of the spectra in a semi-logarithmic representation. The influences of some main source parameters, such as the neutral gas pressure, extraction voltage, microwave power, and bias disk voltage, on the high energy electrons are systemically investigated.

A new room temperature LECR5 ion source for the SESRI project

The Space Environment Simulation and Research Infrastructure project, which uses various ion beams as irradiated materials in life science research, is being built at the Harbin Institute of Technology. A new room temperature electron cyclotron resonance ion source, the Lanzhou Electron Cyclotron Resonance Ion Source No. 5 (LECR5), has been designed and constructed. It is an intense, highly charged, heavy ion beam injector which generates ion beams from H to Bi, typically ∼50 eμA ²⁰⁹Bi³²⁺. The LECR5 is designed to operate at microwave frequencies in the range of 14.5-18 GHz. The typical magnetic parameters are designed based on those optimized for SECRAL, which operates at 18 GHz. This paper presents the LECR5 ion source, its test bench, and the preliminary beam results.

Production of intense uranium beams with inductive heating oven at Institute of Modern Physics

HIAF (High Intensity heavy ion Accelerator Facility) is a new accelerator complex under construction at the Institute of Modern Physics. As the main injector of this project, the high-charge-state ECR ion source needs to provide intense uranium beams, such as 700 eμA of U³⁵⁺. This requires the performance of metal ovens to be further improved so that the crucible can operate at an ultrahigh temperature for a long time without damage in a high magnetic field (>3 T). In order to meet these requirements, an inductive oven with special thermal shielding and support has been developed in the past two years. The off-line test result has shown that this oven can reach up to 2000 °C with ∼1.2 kW of heating power. After ∼5 days of continuous running on the SECRAL-II platform, the tantalum crucible survived. In this contribution, we will discuss the structure of this inductive oven and analyze the test results as well.

[Adult femur CT modeling and 3D automatic measurement of anatomical parameters]

Objective: To reconstruct a 3D model from adult femur CT scan data and automate a measurement of femoral anatomical parameters to study the characteristics of Chinese femur anatomical parameters. Methods: Using Mimics17.0, models from the CT data of 148 adult patients were established. The completed model was imported into Geomagic Studio and the anatomical landmarks of the femur were extracted to establish 3D coordinate system and unified coordinate system. Programmed with Matlab, using the nearest point iterative ICP algorithm and the 3D automatic extraction algorithm of anatomical landmarks to provide precision positioning, the femoral anatomical parameters were automatically measured and analyzed. The data were compared by using independent sample t test. Results: In this group, the diameter of the male femoral condyle was (84.1±3.6) mm, and it was (74.8±3.3) mm in the female; the anteroposterior diameter of the male femoral condyle was (66.5±3.7) mm, and it was (61.2±3.5) mm in the female; the diameter of the male ball head was (48.8±2.1) mm and it was (43.4±2.2) mm in the female; the differences between the two genders were all statistically significant (t=16.21, 8.84, 15.20, all P<0.05). The male femoral moment radius was (112.5±24.5) mm, and it was (124.7±19.2) mm in the female (t=3.30, P=0.002). The neck angle in male participants was 124.9°±4.0°, and it was 126.1°±5.5° in the female (t=1.40, P>0.05). As the height growed, most of the anatomical parameters increased accordingly. Conclusions: The 3D automatic measurement of femoral anatomical parameters is more reproducible and accurate than manual measurement. It is necessary to establish and enrich the femoral anatomical database to design and develop internal fixation products that meet the needs of Chinese people.

P1216Evaluation of alphavbeta3 integrin-targeted positron emission tomography and photoacoustic tracer for imaging of carotid plaque in apoE–/– mice

Background

Cardiovascular disease is the leading cause of death in the world. The majority of cardiovascular events result from the rupture of vulnerable atherosclerotic plaques, which are characterized by high and active macrophage content. The integrin αVβ3 is expressed by activated macrophages and endothelial cells in atherosclerotic lesions and thus is a marker of high-risk plaques. Therefore, 89Zr-RGD-melanin nanoparticle (MNP) positron emission tomography (PET)/photoacoustic imaging (PAI) imaging of αVβ3 expression in plaques might provide a novel noninvasive biomarker of plaque vulnerability.

Purpose

In this study, the intrinsic photoacoustic signals and the native strong chelating properties with metal ions of MNP, positron-emitting metal ions 89Zr and αVβ3 integrins targeting ability of cyclic c (RGDfC) peptide was employed to construct an efficient nanoplatform. And we evaluated the feasibility of 89Zr-RGD-MNP PET/PAI of αVβ3 expression in vivo and in vitro.

Methods

We conjugated αVβ3 integrins, cyclic c (RGDfC) peptide, to MNP and chelated the long-lived positron-emitting nuclide 89Zr. The bio-stability and targeting action was detected in macrophages. And the PET/PAI imaging was performed in apoE−/− mice with partial carotid ligation leading to atherosclerosis. In PET imaging, tracer uptake was measured in the stenotic areas of the carotid arteries, as well as on the contralateral side at different time points in vivo. In PAI, photoacoustic signal was measured in the atherosclerosis of the carotid arteries in vivo. Melanin staining and immunohistochemistry of αVβ3 expression were detected in atherosclerosis of the carotid arteries.

Results

89Zr-RGD-MNP showed excellent bio-stability and targeting action. PET imaging showed specific tracer accumulation at plaques in the left carotid artery, confirmed by competitive receptor blocking studies and the contrast in the right carotid artery. In the biodistribution studies, the left carotid (5.29%±0.78%) showed higher uptake than the right carotid (2.11%±1.55%). PAI showed the PA signal in the surgery group (452±85 a.u.) were stronger than the control (156±45 a.u.) and blocking group (254±66 a.u). The result was consistent with PET imaging and the presence of nanoparticles, as indicated by pathological examinations. These results presented good in vivo multimodality imaging (PET/PAI) properties.

Conclusions

We have developed 89Zr-labeled atherosclerotic plaques imaging agents based on the natural melanin nanoparticle. 89Zr-RGD-MNP demonstrates specific tracer accumulation in mice atherosclerotic carotid plaques. In this model, its uptake was associated with αVβ3 expression. 89Zr-RGD-MNP is a potential tracer for noninvasive imaging in atherosclerosis.

Acknowledgement/Funding

National Natural Science Foundation of China 81770452, 81470401

[Effect of intranasal excision under open the nasal vestibular flap on nasal vestibular cyst under nasal endoscopy]

Objective:Objective:To observe the clinical Effect of intranasal excision under open the nasal vestibular flap on nasal vestibular cyst under nasal endoscopy.Method:Forty-five patients with nasal vestibular cyst were randomly divided into two groups: nasal vestibule flap group (n=25) and labial gingival crevicular approach group (n=20).Comparison of two groups of patients with operation time, intraoperative blood loss, wound healing time, postoperative local numbness or pain, 1 week after eating the inconvenience, the degree of postoperative wound pain, postoperative facial swelling degree were compared between the two groups.Result:①The operation of the two groups was successful, and all patients were not relapse followed-up for 1-3 years and averaged 1.5 years. ②Compared with labial gingival crevicular groove approach group,the amount of bleeding, wound healing time, postoperative upper lip numbness in local incidence, one week after operation of eating or the incidence rate of eating inconvenience pain aggravate in nasal vestibular double flap group with were all statistically significant (P<0.05).The operation time of the two groups were not statistically significant(P>0.05).③The degree of pain and swelling of the face in the nasal vestibule flap group were significantly lighter than that of the labial gingival crevicular approach group(P<0.05).Conclusion:Endoscopic resection of nasal vestibular cyst through nasal vestibule flap approach has advantages in less intraoperative bleeding,shorter wound healing time,much less postoperative local reaction, less pain and lower postoperative recurrence rate, and does not increase operative time.

Bisphenol A exposure promotes HTR-8/SVneo cell migration and impairs mouse placentation involving upregulation of integrin-β1 and MMP-9 and stimulation of MAPK and PI3K signaling pathways

In this study, we investigated the effect of Bisphenol A (BPA), an endocrine-disrupting chemical, on the migration of human trophoblasts and mouse placentation by using the primary extravillous trophoblast (EVT) and its cell line HTR-8/SVneo, villous explant cultures, and pregnant mice. BPA increased EVT motility and the outgrowth of villous explants in a dose-dependent manner. BPA also increased the protein levels of integrin-β1 and matrix metalloproteinase (MMP)-9 in human EVTs. Low-dose BPA (≤50 mg) increased the protein levels of MMP-9 and MMP-2 as well as integrin-β1 and integrin-α5 in mouse placenta and decreased the proportion of the labyrinth and spongiotrophoblast layers. Inhibitors of mitogen-activated protein kinase (MAPK) U0126 and phosphatidylinositol-3-kinases (PI3K) LY294002 reversed the protein levels of integrin-β1 and MMP-9 as well as the migratory ability induced by BPA. In conclusion, these results indicated that BPA can enhance trophoblast migration and impair placentation in mice by a mechanism involving upregulation of integrin(s) and MMP(s) as well as the stimulation of MAPK and PI3K/Akt (protein kinase B) signaling pathways.

[Progress in the prognostic factors associated with the sudden sensorineural hearing loss]

Sudden sensorineural hearing loss is a frequent emergency in otology, and there are various pathogenesises currently, such as disturbance of inner ear circulation, viral infection and autoimmune response are generally accepted. However, the varied therapeutic treatments are mostly disoriented that we can' t evaluate the clinical effects. So it is important to discuss the prognostic factors associated with the sudden sensorineural hearing loss, and provide guidance for clinical treatment. Here is to make a review of the influence of the factors that affecting the prognosis of sudden sensorineural hearing loss, including age, sex, ear side, treatment time, degree of hearing loss, comorbidities, audiological features, mental status, concurrent symptoms and genes.

Acupuncture in endocrine disorders: a critical appraisal

Acupuncture is an integral part of ancient Chinese medical practice. The technique has been used extensively in pain relief and is being tried for many other chronic conditions. Industrial development and affluence lead to the increase in the prevalence of many endocrine disorders such as diabetes, obesity, and polycystic ovarian disease. The rising prevalence of the endocrine morbidity is observed in both the developing and developed nations. The management of these disorders involves major lifestyle modification coupled with a long-term drug intake. In such situations, patients often look at alternative therapeutic options existing in complementary and alternative medicine. The globalization of the world medical practice has led to the spread of acupuncture beyond China to other parts of the world. Acupuncture has been tried extensively in the management of various endocrine disorders with inconsistent results. In this review, we highlight the principles of acupuncture and its role in the management of various endocrine disorders.

[Clinical characteristics and surgical treatment of types Ⅱ to Ⅳ external auditory canal cholesteatoma]

Objective:The aim of this study is to explore the clinical characteristics,diagnostic methods,surgical procedures and results of typesⅡ to Ⅳexternal auditory canal cholesteatoma.Method:In the 63 cases,there were 39 patients suffering typeⅡexternal auditory canal cholesteatoma,22 patients suffering typeⅢ and 2 patients suffering type Ⅴ.All patients had surgeries to remove the lesion under the microscope,and underwent canaloplasty or tympanoplasty or modified mastoidectomy as well.Result:There were 2 cases occurred meatal stenosis postoperatively ,as well as 2 cases of cholesteatoma recurrenced,and were cured after second operation.Four patients'hearing level were not improve postoperatively due to the severe damage of their ossicular chain.All other patients were cured with one operation,which the cavity with good skin coverage and there has been no recurrence.Conclusion:Temporal bone CT scan has important significance in the diagnosis and classification of external auditory canal cholesteatoma.Prevention and early diagnosis are particularly important.Surgical treatment should completely remove the lesion,restore hearing according to the situation,and appropriate surgical treatment should be taken according to the classification,location of external auditory canal cholesteatoma as well as hearing level of patients.

Use of high-throughput targeted exome sequencing in genetic diagnosis of Chinese family with congenital cataract

AIM

To identify disease-causing mutation in a congenital cataract family using enrichment of targeted genes combined with next-generation sequencing.

METHODS

A total of 371 known genes related to inherited eye diseases of the proband was selected and captured, followed by high-throughput sequencing. The sequencing data were analyzed by established bioinformatics pipeline. Validation was performed by Sanger sequencing.

RESULTS

A recurrent heterozygous non-synonymous mutation c.130G>A (p.V44M) in the GJA3 gene was identified in the proband. The result was confirmed by Sanger sequencing. The mutation showed co-segregation with the disease phenotype in the family but was not detected in unaffected controls.

CONCLUSION

Targeted exome sequencing is a rapid, high-throughput and cost-efficient method for screening known genes and could be applied to the routine gene diagnosis of congenital cataract.

Dietary methionine requirement of Jing Brown layer hens from 9 to 17 weeks of age

This study was conducted to evaluate the effect of dietary methionine (Met) supplementation in growth performance and reproductive performance of Jing Brown layer hens. A total of 375 9-week-old Jing Brown layer hens were allocated equally to five treatments consisting of 5 replicates with 15 hens. Hens were fed with a diet of corn and soya bean meal supplemented with 0.23%, 0.27%, 0.31%, 0.35% and 0.39% Met respectively. Different Met levels did not significantly affect average daily feed intake (ADFI), average daily gain (ADG) and feed/gain ratio (F/G) (p > 0.05), whereas flock uniformity (FU) and jejunum index were significantly different (p < 0.05), and the largest FU was observed in 0.31% Met. Dietary supplementation of Met significantly affected reproductive system development (p < 0.05), and 0.27-0.31% Met obtained optimal reproductive system development. Different Met levels significantly affected serum uric acid and alkaline phosphatase. Moreover, the relatively higher reproductive hormones in serum were observed in 0.27% Met. Analysis of quadratic curve estimation of flock uniformity, the total number of follicles, the primary follicles and the secondary follicles showed that the optimal Met levels were 0.293%, 0.286%, 0.286% and 0.288%, which could be averaged to 0.288%. These results suggested that the optimal Met requirement for Jing Brown layer hens from 9 to 17 weeks old is 0.29%.

[Effectiveness research of medicated γ intrauterine device and medicated genefix intrauterine device inserted immediately after abortion]

OBJECTIVE

To compare the effectiveness of medicated γ intrauterine device (IUD) and medicated genefix IUD inserted immediately after abortion.

METHODS

A multicenter clinical trail was performed for the study from Mar. 2012 to Jan. 2013. Totally 840 women who volunteered to participate were randomly allocated to γ-group (medicated γ IUD) or genefix-group (medicated genefix IUD) immediately after abortion. While 464 abortion women who had not used IUD or steroids contraceptive methods were chosen as control group. The effectiveness of the IUD were followed up for 1 year. All women were required to record the number of vaginal bleeding days and blood volume of vaginal bleeding within 3 months after abortion.

RESULTS

At the 12(th) month, the expulsion was the most common reason for termination. The expulsion rates of genefix-group and γ-group were 2.48/100 women years and 3.12/100 women years, respectively (P>0.05). For the expulsion reasons, IUD moving down could account for more than seventy percent. The removal rate for IUD usage of two IUD groups were almost equal (3.91/100 women years verus 4.35/100 women years), the differences were not statistically significant (P>0.05). At the 90(th) day after abortion, comparing with control group, the bleeding and (or) spotting days of genefix-group and γ-group extended by 3.9 and 2.6 days respectively, the differences had statistical significance between the three groups (P<0.05). Among the bleeding and (or) spotting days, spotting days prolonged significantly. At the 12(t)h month, spotting days of genefix-group and γ-group were (9.2±5.9) days and (8.5±4.6) days respectively, more than (5.2±4.0) days of control group. The differences had statistical significance between IUD with control group (P<0.05), and had not between the two kinds of IUD (P>0.05).

CONCLUSION

The insertion of medicated genefix IUD and medicated γ IUD immediately after abortion is safe, feasible, has slight side effects and could be effective contraception.

Captures of Ostrinia furnacalis (Lepidoptera: Crambidae) With Sex Pheromone Traps in NE China Corn and Soybeans

Ostrinia furnacalis (Guenée) (Lepidoptera: Crambidae), commonly referred to as the Asian corn borer, is the most important corn pest in Asia. Although capturing males with pheromone traps has recently been the main monitoring tool and suppression technique, the best trap designs remain unclear. Commercially available Delta and funnel traps, along with laboratory-made basin and water traps, and modified Delta traps, were evaluated in corn and soybean fields during 2013-2014 in NE China. The water trap was superior for capturing first-generation O. furnacalis (1.37 times the Delta trap). However, the basin (8.3 ± 3.2 moths/trap/3 d), Delta (7.9 ± 2.5), and funnel traps (7.0 ± 2.3) were more effective than water traps (1.4 ± 0.4) during the second generation. Delta traps gave optimal captures when deployed at ca. 1.57 × the highest corn plants, 1.36× that of average soybean plants, and at the field borders. In Delta traps modified by covering 1/3 of their ends, captures increased by ca. 15.7 and 8.1% in the first and second generations, respectively. After 35 d in the field, pheromone lures were still ca. 50% as attractive as fresh lures, and retained this level of attraction for ca. 25 more days. Increased captures (first and second generation: 90.9 ± 9.5%; 78.3 ± 9.3%) were obtained by adding a lure exposed for 5 d to funnel traps baited with a 35-d lure.

Activation and blockade of serotonin7 receptors in the prelimbic cortex regulate depressive-like behaviors in a 6-hydroxydopamine-induced Parkinson's disease rat model

The role of serotonin7 (5-HT7) receptors in the regulation of depression is poorly understood, particularly in Parkinson's disease-associated depression. Here we examined whether 5-HT7 receptors in the prelimbic (PrL) sub-region of the ventral medial prefrontal cortex (mPFC) involve in the regulation of depressive-like behaviors in sham-operated rats and rats with unilateral 6-hydroxydopamine lesions of the medial forebrain bundle. The lesion induced depressive-like responses as measured by the sucrose preference and forced swim tests when compared to sham-operated rats. Intra-PrL injection of 5-HT7 receptor agonist AS19 (0.5, 1 and 2 μg/rat) increased sucrose consumption, and decreased immobility time in sham-operated and the lesioned rats, indicating the induction of antidepressant-like effects. Further, intra-PrL injection of 5-HT7 receptor antagonist SB269970 (1.5, 3 and 6 μg/rat) decreased sucrose consumption, and increased immobility time, indicating the induction of depressive-like responses. However, the doses producing these effects in the lesioned rats were higher than those in sham-operated rats. Neurochemical results showed that intra-PrL injection of AS19 (2 μg/rat) increased dopamine, 5-hydroxytryptamine (5-HT) and noradrenaline (NA) levels in the mPFC, habenula and ventral hippocampus (vHip) in sham-operated and the lesioned rats; whereas SB269970 (6 μg/rat) decreased 5-HT levels in the habenula and vHip, and the levels of NA in the mPFC, habenula and vHip in the two groups of rats. The results suggest that 5-HT7 receptors in the PrL play an important role in the regulation of these behaviors, which attribute to changes in monoamine levels in the limbic and limbic-related brain regions after activation and blockade of 5-HT7 receptors.

Allelic methylation status of CpG islands on chromosome 21q in patients with Trisomy 21

Trisomy 21 is a chromosomal condition caused by the presence of all or part of an extra 21st chromosome. There has been limited research into the DNA methylation status of CpG islands (CGIs) in trisomy 21, therefore, exploring the DNA methylation status of CGIs in 21q is essential for the development of a series of potential epigenetic biomarkers for prenatal screening of trisomy 21. First, DNA sequences of CGIs in 21q from the USCS database were obtained and 149 sequences and 148 pairs of primers in the BGI YH database were aligned. All 300 cases were analyzed by a heavy methyl-polymerase chain reaction (HM-PCR) assay and a comparison of the DNA methylation status of CGIs was made between trisomy 21 and the control. The HM-PCR assay results did not show a difference in the DNA methylation status between individuals with trisomy 21 and the control. In total, there were 11 CGIs that showed various DNA methylation statuses between Japanese and Chinese patients. Subsequently, bisulfite genomic sequencing found variations in the methylation status of CpG dinucleotides in CGIs (nos. 14, 75, 109, 134 and 146) between trisomy 21 and the control. The different DNA methylation status of CpG dinucleotides in CGIs may be a potential epigenetic marker for diagnosing trisomy 21. No difference was identified in the DNA methylation status of 21q CGIs among Chinese individuals with trisomy 21 and the control. The homogeneity of the DNA methylation status of 21q CGIs in Chinese patients indicates that DNA methylation is likely to be an epigenetic marker distinguishing ethnicities.

Relationship between LTR methylation and gag expression of HIV-1 in human spermatozoa and sperm-derived embryos

OBJECTIVE

Studying the methylation status of long terminal repeats (LTR) and its relationship to gag expression of HIV-1 in order to explore regulation mechanism of HIV-1 gene expression in vertical transmission from sperm to embryo.

METHODS/PRINCIPAL FINDINGS

Sperm samples were collected from a healthy donor and seven patients with HIV/AIDS. Zona-free hamster ova were fertilized by donor's spermatozoa transfected with pIRES2-EGFP-LTR-gag and patient's spermatozoa to obtain zygotes and 2-cell embryos, respectively. Interspecific in vitro fertilization, bisulfite sequencing PCR (BSP), RT-PCR, nested RT-PCR, nested real-time qRT-PCR and 2(-△△Ct) method, indirect immunofluoresence (IF) assay were performed. For donor's samples, the methylation rates of HIV-1 LTR were 0.56%, 1.67%, 0.56%, 0.56% in plasmid, spermatozoa, zygotes and 2-cell embryos, respectively while spermatozoa were transfected with unmethylated plasmid, and were 95.0%, 84.44%, 3.3%, 1.67% while transfected with methylated plasmid. The positive bands for HIV-1 gag cDNA were detected in spermatozoa and 2-cell embryos. The positive signals for HIV-1 p24 Gag protein were detected in 2-cell embryos but not in spermatozoa. For patient's samples, methylation rates of HIV-1 LTR were different in spermatozoa among patients. After fertilization, CpG sites in HIV-1 LTR were highly demethylated in zygotes and 2-cell embryos. The gag transcription levels increased with decreasing of methylation rates of HIV-1 LTR, which showed a strong negative correlations between gag transcription levels and methylation rates of HIV-LTR ether in the spermatozoa (r = -0.9877, P<0.0001) or in the sperm-derived 2-cell embryos (r = -0.9092, P = 0.0045).

CONCLUSION

LTR methylation regulates expression of HIV-1 gag in vertical transmission from sperm to embryo.

[Semen quality of the men from six districts in Chongqing]

OBJECTIVE

To investigate the quality and spatial distribution features of semen and to evaluate the reproductive health of the males in the Chongqing section of the Three-Gorge Reservoir area.

METHODS

We collected semen samples by masturbation after 2 -7 days of abstinence from the men in Nan'an, Shapingba, Zhongxian, Wanzhou, Yunyang and Wushan of Chongqing, which are geographically and demographically representative of the Three-Gorge Reservoir area. We analyzed the semen quality of all the samples and evaluated the reproductive health of the men.

RESULTS

The mean value of the five semen parameters of the male subjects from the six districts was within the normal range, including semen volume, sperm concentration, total sperm count, rapid progressive motile sperm, and total motile sperm. Those from Shapingba, Yunyang and Zhongxian exhibited abnormal sperm motility. According to the WHO criteria, normal value of all the semen parameters was found in less than 50% of the semen samples from the six districts, in 47% of those from Yunyang, and only 16% of those from Wanzhou. Spatial distribution maps of the semen parameters revealed significant spatial differences in seminal quality among the six districts, the highest in Yunyang, and the lowest in Wanzhou and Wushan that are located in the middle and lower reaches of the Three-Gorge Reservoir area.

CONCLUSION

The mean value of semen parameters was low in a large proportion of men in the Chongqing section of the Three-Gorge Reservoir area, with spatial differences along the Changjiang river.

In vitro study on vertical transmission of the HIV-1 gag gene by human sperm

HIV/AIDS is a major public health problem worldwide. To explore the feasibility of HIV vertical transmission by human sperm, plasmid construction and transfection, interspecific in vitro fertilization of zona-free hamster ova by human sperm, fluorescence in situ hybridization (FISH), RT-PCR, and immunofluorescence assay (IFA) were carried out. The FISH signals for HIV-1 gag DNA were observed in the nuclei and chromosomes of transfected human sperm, male pronuclei of zygotes, and nuclei of blastomeres of two-cell embryos, indicating that the HIV-1 gag gene could be transmitted via the sperm membrane and integrated into the sperm genome. In contrast, human sperm carrying the target gene achieved normal fertilization, and replication of the sperm-mediated target gene was synchronized with the host genome. Using RT-PCR, the positive bands for the target gene were observed in the transfected human sperm and two-cell embryos. These results further confirm that the target gene can be transcribed into mRNA in human sperm and embryonic cells. Positive signals for the HIV-1 p24 gag protein were shown by IFA in two-cell embryos containing the sperm-mediated target gene and not in the transfected human sperm, which indicated that the sperm-mediated target gene could be translated to make HIV-1 p24 gag protein in embryonic cells, but not in sperm cells. The results provide evidence for possible vertical transmission of the HIV-1 gag gene to the embryo by fertilizing sperm in vitro.

The integrated HIV-1 provirus in patient sperm chromosome and its transfer into the early embryo by fertilization

Complete understanding of the route of HIV-1 transmission is an important prerequisite for curbing the HIV/AIDS pandemic. So far, the known routes of HIV-1 transmission include sexual contact, needle sharing, puncture, transfusion and mother-to-child transmission. Whether HIV can be vertically transmitted from human sperm to embryo by fertilization is largely undetermined. Direct research on embryo derived from infected human sperm and healthy human ova have been difficult because of ethical issues and problems in the collection of ova. However, the use of inter-specific in vitro fertilization (IVF) between human sperm and hamster ova can avoid both of these problems. Combined with molecular, cytogenetical and immunological techniques such as the preparation of human sperm chromosomes, fluorescent in situ hybridization (FISH), and immunofluorescence assay (IFA), this study mainly explored whether any integrated HIV provirus were present in the chromosomes of infected patients' sperm, and whether that provirus could be transferred into early embryos by fertilization and maintain its function of replication and expression. Evidence showed that HIV-1 nucleic acid was present in the spermatozoa of HIV/AIDS patients, that HIV-1 provirus is present on the patient sperm chromosome, that the integrated provirus could be transferred into early embryo chromosomally integrated by fertilization, and that it could replicate alongside the embryonic genome and subsequently express its protein in the embryo. These findings indicate the possibility of vertical transmission of HIV-1 from the sperm genome to the embryonic genome by fertilization. This study also offers a platform for the research into this new mode of transmission for other viruses, especially sexually transmitted viruses.

[An analysis on chromosome X, Y and 18 in the spermatozoa of asthenospermia patients by triple-color fluorescence in situ hybridization]

OBJECTIVE

To analyze the numerical aberration of chromosome X, Y and 18 in the spermatozoa of asthenospermia patients by triple-color fluorescence in situ hybridization.

METHODS

The experiment included 10 asthenospermia patients and 5 healthy men with normal semen quality as controls. Fluorescence in situ hybridization (FISH) and probes for chromosomes including X, Y and 18 were used to determine the frequency of the aneuploid of the chromosomes in spermatozoa.

RESULTS

Of the 45,547 spermatozoa counted from the semen samples, the hybridization rate was 99.18%. The frequencies of the chromosome disomies including XX18, XY18, YY18, X1818 and Y1818 were (0.124 +/- -0.086)%, (0.360 +/- 0.380)%, (0.109 +/- 0.195)%, (0.342 +/- 0.746)% and (0.299 +/- 0.564)% in the case group and (0.014 +/- 0.019)%, (0.090 +/- 0.080)%, (0.030 +/- 0.031)%, (0.068 +/- 0.103)% and (0.075 +/- 0.083)% in the control. The sperm aneuploid rate was 9.25% in the former and 2.70% in the latter, with significant difference in between (P< 0.01).

CONCLUSION

Asthenospermia patients have a higher aneuploid rate of sperm chromosome than normal fertile men. However, larger samples are yet to be studied to obtain more scientific evidence.

Medical radiation usage and exposures from medical X ray diagnosis in Shandong province of China

Shandong province is situated in the eastern part of China with a population of 88 million. A collaborative survey was conducted in 1999 to investigate the medical radiation usage and the patients' exposures from medical X ray diagnosis in this province. There were three stages in this survey: general survey, sampling survey and dose survey. Patients' entrance surface doses (ESD) were measured using thermoluminescence dosemeters (TLDs) attached to the patient's skin. All the hospitals in this province and 2153 patients were included in this survey. The frequencies of tele- and brachytherapy were 1.450 and 1.685 per 1000 population in 1996 and 1998 respectively. The frequency of diagnostic nuclear medicine was 0.325 and 0.412 per 1000 population in 1996 and 1998 respectively; for therapeutic nuclear medicine, it was 0.015 and 0.021. The total annual frequencies of every type of X ray examination and interventional radiology (IVR) in 1996 and 1998 were 179.8 and 200.0 per 1000 population respectively. The main type of X ray examination was chest fluoroscopy, which made up about 39% of the total. The average entrance surface doses were comparatively high for the examinations of CT, gastrointestinal tract, lumbarspine, urography, angiography, hip and cerebral angiography.

Radiation exposure to patients during paediatric cardiac catheterisation

Radiation doses were investigated for 18 infants and children undergoing cardiac catheterisation procedures with thermoluminescence dosemeters. The range of integrated current values used during cardiac catheterisation procedure was wide, from 12.2 to 1195.8 mA.min (mean 604.9). The average was 22.9 mA.min for fluoroscopy, and 616.1 mA.min for cineangiography, and the ratio of cineangiography to fluoroscopy ranged from 10.5 to 89.5 with an average of 34.0. The cineangiographic contribution was estimated to be 90% of the total doses. The entrance surface doses and thyroid doses varied widely. The ratio of maximum to minimum for entrance surface doses was 98.5, for left and right thyroid it was 59.8 and 104.4, respectively. The analysis of the entrance surface doses in three age groups showed that there was no significant difference among them. There was a weak inverse relation between the thyroid dose and the weight of the patient, while no correlation was found between the thyroid dose and the entrance surface dose. The average of entrance surface doses to the patients was 847.3 mGy, which was 1-2 orders of magnitude higher than common X ray examinations.

Interaction of Na+, K+, and Cl- with the binding of amphetamine, octopamine, and tyramine to the human dopamine transporter

Little information is available on the role of Na+, K+, and Cl- in the initial event of uptake of substrates by the dopamine transporter, i.e., the recognition step. In this study, substrate recognition was studied via the inhibition of binding of [3H]WIN 35,428 [2beta-carbomethoxy-3beta-(4-fluorophenyl)[3H]tropane], a cocaine analogue, to the human dopamine transporter in human embryonic kidney 293 cells. D-Amphetamine was the most potent inhibitor, followed by p-tyramine and, finally, dl-octopamine; respective affinities at 150 mM Na+ and 140 mM Cl- were 5.5, 26, and 220 microM. For each substrate, the decrease in the affinity with increasing [K+] could be fitted to a competitive model involving the same inhibitory cation site (site 1) overlapping with the substrate domain as reported by us previously for dopamine. K+ binds to this site with an apparent affinity, averaged across substrates, of 9, 24, 66, 99, and 134 mM at 2, 10, 60, 150, and 300 mM Na+, respectively. In general, increasing [Na+] attenuated the inhibitory effect of K+ in a manner that deviated from linearity, which could be modeled by a distal site for Na+, linked to site 1 by negative allosterism. The presence of Cl- did not affect the binding of K+ to site 1. Models assuming low binding of substrate in the absence of Na+ did not provide fits as good as models in which substrate binds in the absence of Na+ with appreciable affinity. The binding of dl-octopamine and p-tyramine was strongly inhibited by Na+, and stimulated by Cl- only at high [Na+] (300 mM), consonant with a stimulatory action of Cl- occurring through Na+ disinhibition.

Modeling of the interaction of Na+ and K+ with the binding of dopamine and [3H]WIN 35,428 to the human dopamine transporter

Although much is known about the effects of Na+, K+, and Cl- on the functional activity of the neuronal dopamine transporter, little information is available on their role in the initial event in dopamine uptake, i.e., the recognition step. This was addressed here by studying the inhibition by dopamine of the binding of [3H]WIN 35,428 [2beta-carbomethoxy-3beta-(4-fluorophenyl)[3H]tropane], a phenyltropane analogue of cocaine, to the cloned human dopamine transporter expressed in HEK-293 cells. The decrease in the affinity of dopamine (or WIN 35,428) binding affinity with increasing [K+] could be fitted to a competitive model involving an inhibitory cation site (1) overlapping with the dopamine (or WIN 35,428) domain. The K+ IC50 for inhibiting dopamine or WIN 35,428 binding increased linearly with [Na+], indicating a K(D,Na+) of 30-44 mM and a K(D,K+) of 13-16 mM for this cation site. A second Na+ site (2), distal from the WIN 35,428 domain but linked by positive allosterism, was indicated by model fitting of the WIN 35,428 binding affinities as a function of [Na+]. No strong evidence for this second site was obtained for dopamine binding in the absence or presence of low (20 mM) Cl- and could not be acquired for high [Cl-] because of the lack of a suitable substitute ion for Na+. The K(D) but not Bmax of [3H]WIN 35,428 binding increased as a function of the [K+]/[Na+] ratio regardless of total [Cl-] or ion tonicity. A similar plot was obtained for the Ki of dopamine binding, with Cl- at > or = 140 mM decreasing the Ki. At 290 mM Cl- and 300 mM Na+ the potency of K+ in inhibiting dopamine binding was enhanced as compared with the absence of Cl- in contrast to the lack of effect of Cl- up to 140 mM (Na up to 150 mM). The results indicate that Cl- at its extracellular level enhances dopamine binding through a mechanism not involving site 1. The observed correspondence between the WIN 35,428 and dopamine domains in their inclusion of the inhibitory cation site explains why many of the previously reported interrelated effects of Na+ and K+ on the binding site of radiolabeled blockers to the dopamine transporter are applicable to dopamine uptake in which dopamine recognition is the first step.

Occupational exposure in pediatric cardiac catheterization

Radiation doses to staff involved with pediatric cardiac catheterization were measured using thermoluminescent dosimeters in 18 procedures. The average doses to the lens and thyroid, and the effective dose per procedure to the main operating physicians was 88, 180, and 8 microSv, respectively; to assistant physicians, 23, 51, and 2 microSv; and to technicians, 23, 27, and 2 microSv. In some procedures, the dose to the technician's hand approached 1,500 microSv. The doses received by physicians were proportional to cineangiographic time but with no correlation with integrated currents. The number of procedures which may be performed in a year by individual staff members was estimated to be 430 and 2,780 procedures for physicians and assistants, respectively. It was suggested that the front of the neck is an adequate position for the dosimeter to measure doses during pediatric catheterization.

Practicing with the urban underserved. A qualitative analysis of motivations, incentives, and disincentives

OBJECTIVE

To investigate the personal characteristics and professional experiences of medical providers working with medically underserved urban populations.

DESIGN

Focus groups of primary care providers.

SETTING

Public and private clinics in Salt Lake City, Utah, in which the providers had ongoing relationships with medically underserved patients.

PARTICIPANTS

Twenty-four providers (11 men and 13 women), including 12 physicians (three family physicians, seven pediatricians, and two psychiatrists), one dentist, three physician assistants, and eight nurse practitioners participated in three focus groups.

MAIN OUTCOME MEASURE

Interpretative analysis of verbatim quotations regarding personal beliefs, feelings, and practice experiences.

RESULTS

Participants revealed a strong sense of service to humanity and pride in making a difference. They thrive on the challenge of creatively dealing with their patients' complex human needs with limited health care resources. Factors critical to survival in an urban underserved setting include a hardy personality style, flexible but controllable work schedule, and multidisciplinary practice team. The camaraderie and synergy of teams generate personal support and opportunities for continuing professional development.

CONCLUSIONS

Increasing the numbers of health care professionals wanting to work with the medically underserved may be facilitated through refining admissions criteria to schools for health care professionals to include values and personality characteristics, emphasizing within curricula the important skills and practice styles necessary to work with underserved patients, and ensuring that underserved practice environments provide support through multidisciplinary teams and structured work hours. These potentially effective approaches could increase success in recruiting and retaining health care professionals to work with medically underserved patients.

[Surgical treatment of constrictive pericarditis in 162 cases]

The authors reports the experience of surgical treatment of constrictive pericarditis in 162 cases. Age ranged from 6 to 66 years old. The cardiac function and circulatory dynamics were improved after decortication of the thickened pericardium in most of the patients. Overall surgical mortality was 3.1%. The major cause of death was low cardiac output syndrome in the early postoperative period. The authors consider that the excision of the thickened pericardium is better to begin from the left to right and the good perioperative management particularly the rational agents is essential in the prevention of low cardiac output syndrome.

[Gastric motility in patients with spleen-deficiency symptoms]

By using a method for synchronously-detecting gastric myoelectric activity and intraluminal pressure and a radioimmunoassay of plasmic motilin, gastric motility, plasmic level of motilin and their relationship in 12 normal individuals and in the patients with a variety of Spleen-Deficiency (SD) Syndromes, i.e. 12 SD with Cold type (H type), 7 SD with Stomach-Yin-Deficiency type(I type), 38 SD with Heat type (R type) and 6 SD with Liver-Qi-Stagnation type (U Type) were investigated. The results showed: degree of myoelectric dysrhythmia and rate of electro-mechanical decouple in all patients (except for I type) were much higher than those in the normals (P < 0.01 or P < 0.05); both mean frequency and amplitude of contraction in the patients were decreased; percentage of contractive action in the patients (except for I type) was lower than that in the normals (P < 0.05); plasmic level of motilin in the patients (except for I type) had a tendency to increase and had a linear correlation to degree of myoelectric dysrhythmia (r = 0.33, P < 0.01). It was suggested that some significant disorders of gastric motility exist in different SD patients and there might be an intrinsic cause effect relationship among increased plasmic motilin, myoelectric dysrhythmia and abnormal mechanical motion. The similar changes suggested that there is pathophysiological mechanism of SD syndrome. Furthermore, this synchronously-detecting method was useful to discover intrinsic relationship between gastric myoelectric activity and mechanical motion.

Understanding physicians' decisions to practice in rural areas as a basis for developing recruitment and retention strategies

The shortage of providers in rural areas is threatening the quality and availability of health care in many communities. The causes of the provider shortage are many and varied-from economic to social to personal. Government programs have addressed the issue of provider supply by offering scholarships and loan repayment programs for medical students who then must fulfil service obligations in underserved settings, among which are rural areas. Experience has shown that once providers complete their obligations under these grant programs, retention of providers in rural areas becomes an even more critical issue. Using focus group research, this study explores the practice setting choices of a group of physicians currently practicing in rural areas. The discussion reveals that personal values are one of the primary motivators for choosing to practice in rural settings while lack of availability of career opportunities for spouses and educational opportunities for children are major obstacles. The health care system poses barriers to success for providers in rural settings. The key rewards from rural practice are the ability to become integrated into the local community and the provider/patient relationships that develop in such settings. These findings are used as the basis for proposing recruitment and retention strategies for providers to improve access to medical care by patients in rural areas.

Comparison of Shams' test for rectal mucus to an immunological test for fecal occult blood in large intestinal carcinoma screening. Analysis of a check-up of 6480 asymptomatic subjects

The sugar moiety detected from rectal mucus by the Galactose oxidase-schiff (Shams' test) is considered a substitutive test for immunological fecal occult blood test (FOBT) in screening colorectal carcinoma. Two strategies of screening were applied in 6480 subjects over 40 years of age, and 130 cm flexible colonoscope used for sigmoidoscopy or pancolonoscopy. Of them, 3820 were taken for immune FOBT (SPA test) and Shams' test. Only those who showed positive tests were chosen for 60 cm flexible sigmoidoscopy, while another 2660 subjects for both sigmoidoscopy and tests at the same time. Additionally, 130 cm flexible pancolonoscopy was carried out in 103 individuals with positive Shams' test for evaluating the false positive rate. Shams' test showed a sensitivity of 85.7% for colorectal cancer, 47.1% for adenomas in preselected patients, while the positive rate of SPA test were 90.5% and 41.2% respectively. In 3820 asymptomatic subjects undergoing sequential screening (aged 45 years and higher), Shams' test showed 9.1% positive, SPA showed 11.2% and 620 (16.2%) subjects were selected for sigmoidoscopy based on their positive galactose oxidase result or positive FOBT result. Two early stage carcinomas and 33 adenomas (0.32% and 4.2% respectively in sigmoidoscopy) were found. Another 2 660 subjects were taken for sigmoidoscopy screening. Four carcinomas and 78 adenomas were found. Of them, only two carcinoma (50%) and 17 (21.8%) or 22 (28.2%) adenomas were positive in Shams' or SPA test. But both tests combined in screening showed a rate of 61.3% in adenomas and 75.0% in cancers. 103 subjects with positive Shams' test were taken for pancolonoscopy. 82.5% showed no lesions.(ABSTRACT TRUNCATED AT 250 WORDS)

The relationship between the structure of plastoquinone derivatives and their biological activity in Photosystem II of spinach chloroplasts

The relationship between the structure of reconstituted plastoquinone derivatives and their ability to recover the Hill reaction was investigated by extraction and reconstitution of lyophilized chloroplasts from spinach, followed by monitoring DCIP photoreduction at 600 nm. The results show that: It is not essential that the plastoquinone side chain be an isoprenoid or a phytol; the activity increases with increasing length of the side chain up to 13-15 carbon atoms; for chains longer than 15 carbon atoms, the activity is practically constant. Lipophilic groups (such as -Br) in the side chain increased the activity, hydrophilic groups (such as -OH) decreased the activity. Conjugated double bonds in the side chain decreased the activity greatly, but non-conjugated double bonds had almost no effect on the activity, indicating a requirement of flexibility of the side chain. The activity is decreased in the order of PQ, UbiQ and MQ, showing a large effect of the ring structure.

Inhibitory effects of dicyclohexylcarbodiimide on spinach cytochrome b6-f complex

The electron transfer activity of purified cytochrome b6-f complex of spinach chloroplast is inhibited by dicyclohexylcarbodiimide (DCCD) in a concentration and incubation time dependent manner. The maximum inhibition of 75% is observed when 300 mole of DCCD per mole of protein (based on cytochrome f) is incubated with cytochrome b6-f complex at room temperature for 40 min. The inhibition of the complex is not due to the formation of cross links between subunits but due to the modification of carboxyls. The amount of DCCD incorporation is directly proportional to the activity loss, suggesting that some carboxyl groups in the complex are directly or indirectly involved in the catalytic function. The incorporated DCCD is located mainly at cytochrome b6 protein. The partially inhibited complex shows the same H+/e-ratio as that of the intact complex when embedded in phospholipid vesicles.

The catalytic role of subunit IV of the cytochrome b6-f complex from spinach chloroplast

The catalytic role of subunit IV, the Mr 17,000 protein, in the chloroplast cytochrome b6-f complex was established through trypsinolysis of the complex under controlled conditions. When purified chloroplast cytochrome b6-f complex, 1 mg/ml, in 50 mM Tris-succinate buffer (pH 7.0) containing 1% sodium cholate and 10% glycerol is treated with 80 micrograms of trypsin at room temperature for various lengths of time, the activity of the cytochrome b6-f complex decreases as the incubation time increases. A maximal inactivation of 80% is reached at 7 min of incubation. The trypsin inactivation is accompanied by the destruction of the proton translocation activity of the complex. No alteration of absorption and EPR spectral properties was observed in the trypsin-inactivated complex. Subunit IV is the only subunit in the cytochrome b6-f complex that is digested by trypsin, and the degree of digestion correlates with the decrease of electron transfer activity. The binding of azido-Q to subunit IV of the complex decreases as the extent of inactivation of the cytochrome b6-f complex by trypsin increases. The residue molecular mass of trypsin cleaved subunit IV is about 14 kDa, suggesting that the cleavage site is at lysine 119 or arginine 125 or 126. When the thylakoid membrane was assayed for cytochrome b6-f complex activity, very little activity was observed; and the activity was not sensitive to trypsinolysis. Upon sonication, activity and sensitivity to trypsinolysis was greatly increased, suggesting that subunit IV protrudes from the lumen side of the membrane.

Identification of a Mr = 17,000 protein as the plastoquinone-binding protein in the cytochrome b6-f complex from spinach chloroplasts

An azidoquinone derivative, 3-azido-2-methyl-5-methoxy-6-(3,7-dimethyl[3H]octyl)-1,4-benzoquinone (azido-Q), was used to study the plastoquinone-protein interaction and to identify the plastoquinone-binding protein in the cytochrome b6-f complex from spinach chloroplasts. When the lipid- and plastoquinone-deficient cytochrome b6-f complex is incubated with varying concentrations of azido-Q and illuminated with long wavelength UV light for 7 min at 2 degrees C, the enzymatic activity, assayed after reconstitution with lipid, decreases as the concentration of azido-Q increases. Maximum inactivation (45%) is observed when 30 mol of azido-Q is used per mol of cytochrome f. The extent of the decrease in activity upon illumination correlates with the amount of azido-Q incorporated into the protein. The 50% inactivation is in good agreement with that expected based on the amount of plastoquinone deficiency of the isolated enzyme complex. When the photolyzed, [3H]azido-Q-treated sample is extracted with organic solvent and subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis, radioactivity is found primarily in the Mr = 17,000 subunit. When the enzyme is pretreated with the electron transfer inhibitor 2,5-dibromo-3-methyl-6-isopropylbenzoquinone or 5-n-undecyl-6-hydroxy-4,7-dioxobenzothiazole, significantly less radioactive label is observed in the Mr = 17,000 protein, suggesting that the action sites of these inhibitors are the same or near the plastoquinone-binding site. When the deficient complex is reconstituted with glycolipid prior to the addition of azido-Q, less than 5% inactivation is observed upon photolysis, and the amount of radioactive label on the Mr = 17,000 protein decreases greatly, suggesting that the plastoquinone-binding site is easily masked by glycolipid when endogenous plastoquinone is absent. Plastoquinol-2 apparently competes with azido-Q for the plastoquinone-binding site since it decreases the radioactive label on the Mr = 17,000 protein.